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Jon Hirschtick is a CAD software developer, founder and former CEO of SolidWorks , a popular solid modeling 3D CAD and CAE system for Microsoft Windows , and Onshape , a cloud platform for product development that includes tools for CAD, data management, collaboration, workflow, analytics, etc.
Hirschtick holds a Bachelors and Master's degree from MIT, graduating in 1986. [ 1 ]
Hirschtick was director of engineering at Computervision from 1991 to 1993, [ 2 ] and a manager at the MIT CADLab. He was a player and instructor on the MIT Blackjack Team [ 3 ] [ 4 ] featured in the movies 21 and Breaking Vegas . [ 5 ] [ 6 ]
Hirschtick founded the SolidWorks Corporation in 1993 using $1 million he made while a member of the MIT Blackjack Team . [ 7 ] [ 8 ] Under his leadership, SolidWorks revenue eventually grew to $600 million. [ 9 ] When Solidworks was acquired by Dassault Systèmes in 1997, Hirschtick continued on as CEO and then a group executive for the next 14 years. [ 10 ] [ 11 ] In October 2011, Hirschtick left Solidworks and in 2012 founded Belmont Technology (later changed to Onshape) with other members of the original SolidWorks team. [ 12 ] [ 13 ] Hirschtick is currently CEO at Onshape. [ 9 ] In October 2019 Onshape entered into an agreement to be acquired by PTC .
Hirschtick was awarded the CAD Society Leadership Award, [ 14 ] joining Autodesk ’s Carl Bass , Dassault Systèmes ’ Bernard Charles , and 3D Systems 's Ping Fu , and is a recipient of the American Society of Mechanical Engineers Leadership Award. [ 15 ] He is a member of the Advisory Board at Boston University and Arcbazar , where he was once director, [ 10 ] and is an advisor to Magic Leap and MarkForged , Inc. [ 16 ] | https://en.wikipedia.org/wiki/Jon_Hirschtick |
Jon Meade Huntsman Sr. (June 21, 1937 – February 2, 2018) [ 1 ] was an American businessman and philanthropist. He was the founder and executive chairman of Huntsman Corporation , a global manufacturer and marketer of specialty chemicals . Huntsman plastics are used in a wide variety of familiar objects, including (formerly) clamshell containers for McDonald's hamburgers. [ 2 ] Huntsman Corporation also manufactures a wide variety of organic and inorganic chemicals that include polyurethanes , textiles, and pigments. [ 3 ] Huntsman's philanthropic giving exceeded $1.5 billion, focusing on areas of cancer research, programs at various universities, and aid to Armenia .
Jon Meade Huntsman was born in Blackfoot, Idaho , into a poor family. [ 4 ] His mother, Sarah Kathleen (née Robison; 1910–1969), [ 5 ] was a homemaker, and his father, Alonzo Blaine Huntsman Sr. (1910–1990), [ 6 ] was a teacher. [ 4 ] [ 7 ] In 1950, the family moved to Palo Alto , California , where Alonzo pursued graduate studies at Stanford University , earning an M.A. and Ed.D. He then became a superintendent of schools in the Los Altos district.
Jon Huntsman attended Palo Alto High School , where he became student body president. He was recruited by Harold Zellerbach, chairman of Crown-Zellerbach Paper Company, to attend the Wharton School of the University of Pennsylvania on a Zellerbach scholarship. [ 8 ] He graduated from Wharton in the spring of 1959, a brother of the Sigma Chi fraternity. [ 9 ]
Huntsman married Karen Haight, daughter of David B. Haight , in June 1959, just weeks after he graduated. [ 4 ] Both were members of the Church of Jesus Christ of Latter-day Saints (LDS Church). In July 1959, Huntsman left to serve for two years in the U.S. Navy as an officer aboard the USS Calvert . [ 4 ] He subsequently earned an MBA from the University of Southern California 's Marshall School of Business in 1966. [ 10 ]
In 1961, Huntsman was employed by Olson Brothers, Inc., an egg-producing company in Los Angeles . [ 11 ] There, he advanced through the ranks to assume the role of vice president of operations. Recognizing that the company sustained substantial losses due to poor packaging, Huntsman became interested in developing a better alternative. His leadership was key in developing the first plastic egg carton. In 1965, he established contact with the polystyrene operations of the Dow Chemical Company . In 1967, he became president of a joint venture between Olson Brothers, Inc., and Dow Chemical, the Dolco Packaging Corporation. [ 2 ]
Seeing an opportunity to create packaging for the emerging fast-food industry, Huntsman left Dolco in 1970 to form the Huntsman Container Corporation with his brother, Alonzo Blaine Jr. (1936–2012), [ 12 ] [ 4 ] and others in Fullerton, California . [ 11 ] [ 13 ] Plants were constructed in Fullerton, California, in 1971 and in Troy, Ohio, in 1972. [ 13 ] Since cash flow was an issue for the new company, Huntsman mortgaged his house and borrowed heavily from banks. In 1973 the company nearly collapsed when an Arab oil embargo cut off supplies of polystyrene, used to make expandable/expanded polystyrene (or EPS). [ 14 ]
In 1974, Huntsman Container Corporation created the "clamshell" container for McDonald's Big Mac . [ 11 ] The company also developed other popular products, including the first plastic plates, bowls, and fast-food containers. [ 8 ] [ 13 ] In 1976, after completion of its first international plant at Skelmersdale, England, a stock deal was arranged to sell Huntsman Container Corporation to Keyes Fiber Company. Huntsman continued to serve as CEO of the container business for four more years and held a directorship of Keyes Fiber Company. [ 13 ]
In 1982, after serving as a mission president for the LDS Church in Washington, DC, for three years, Huntsman continued his plastics and petrochemical pursuits with the formation of a new company, Huntsman Chemical Company , in Salt Lake City, Utah. [ 15 ] In his capacity as CEO and Chairman, he grew the business into a multibillion-dollar company, in part by acquiring a number of businesses in the polystyrene, styrene, and polypropylene industry when they were not seen as profitable. Between 1986 and 2000 Huntsman acquired 36 companies, 35 of which turned out to be hugely profitable. [ 14 ]
In 1994, the Huntsman Chemical Company was renamed the Huntsman Corporation. In 1996, Peter R. Huntsman became President and COO of Huntsman Corporation. In 2000 he replaced his father as the company's CEO. Jon M. Huntsman continued to be involved in the company as Chairman. [ 16 ]
During the 2000s, Huntsman continued its pattern of expansion, both in America and around the world, and reorganization. Huntsman Corporation became publicly traded on the New York Stock Exchange in 2005. [ 17 ] As of 2014, Huntsman reported that it operated 80 manufacturing and R&D facilities in 30 countries and employed approximately 12,000 associates. [ 18 ]
In 2007 Huntsman co-founded an additional new private equity firm, Huntsman Gay Global Capital (now known as HGGC ), with two former Bain Capital executives, Robert C. Gay (1989–2004, managing director) and Greg Benson (executive vice president in London), former Sorenson Capital co-founder and managing director Rich Lawson, and Pro Football Hall of Fame quarterback Steve Young to focus on investments in middle market companies. [ 19 ] [ 20 ]
Huntsman has been awarded thirteen honorary doctorate degrees at various universities. [ 21 ] In 2004 he received the Othmer Gold Medal , awarded by the Chemical Heritage Foundation in recognition of contributions in research, innovation, legislation or philanthropy. [ 22 ] [ 23 ] In 2013 he received the Leadership Award for Lifetime Achievement from the Chemical Marketing and Economics (CM&E) group. [ 24 ] In 2015, he received the Bower Award from the Franklin Institute . [ 25 ]
Huntsman and his wife, Karen, were married for over 58 years and had nine children: Jon Jr. , Peter , Christena, Kathleen ( d. 2010), David, Paul, James, Jennifer, and Mark. At the time of Huntsman's death, they had 56 grandchildren, two of whom were adopted from China and India , and 19 great-grandchildren. [ 4 ]
Huntsman's eldest son, Jon Jr., also served as a Huntsman Corporation executive. He was elected Governor of Utah in 2004 and was a candidate in the Republican Party presidential primaries in 2012. [ 26 ] He has also served in other governmental positions, including as Ambassador of the United States to Singapore , China , and (as of 2017) Russia . [ 27 ]
Huntsman's second eldest son, Peter, took over as CEO of the Huntsman Corporation in July 2000 and as chairman in January 2018. [ 28 ]
On December 8, 1987, Huntsman's son, James, then age 16, was kidnapped and held for $1 million ransom by Nicholas Hans Byrd, a former classmate. FBI agents traced the kidnapper and rescued James unharmed, but agent Al Jacobsen was stabbed in the chest during the arrest. [ 29 ] [ 30 ] [ 31 ]
Huntsman has published a book about his life experience, communicating moral lessons. Titled Winners Never Cheat: Everyday Values We Learned as Children (But May Have Forgotten) , it was published by Wharton School Publishing in 2005. A second edition, titled Winners Never Cheat: Even in Difficult Times , made the Wall Street Journal ' s best-sellers list. [ 32 ]
Huntsman was a four-time cancer survivor. [ 33 ] He died on February 2, 2018, at his home in Salt Lake City. [ 4 ]
As a member of the Latter Day Saints (LDS) Church, Huntsman served as an area seventy from 1996 to 2011. He also served as a regional representative , stake president , and as president of the church's Washington, D.C. Mission from 1980 to 1983.
In 1977 he was chairman of the Western States Republican Leaders. [ 34 ] He was also the Republican Party of Utah national committeeman from 1976 to 1980. [ 34 ] He was a friend of conservative radio talk show host Glenn Beck and has been interviewed on his show. [ 35 ] He was more socially conservative than his son, Jon Huntsman Jr. [ citation needed ] He was close friends with both Glenn Beck on the right and Harry Reid on the left, who both helped further the mission of Huntsman Cancer Institute.
While the Huntsman Container Corporation's first packaging plant was being built in 1970, Huntsman joined the Nixon Administration as Associate Administrator of the Department of Health, Education and Welfare and later served as Special Assistant and Staff Secretary to President Nixon. [ 34 ] Upon completion of the second Huntsman Container site in Troy, Ohio, in 1972, Huntsman left the White House staff to become President and CEO of Huntsman Container, while still serving – in a non-paid position – as a consultant to the Office of the President.
He served as chairman for Utah in Ronald Reagan 's presidential campaign in 1984 and George H. W. Bush 's campaigns in 1988 and 1992 . [ 34 ]
In March 1988, Huntsman announced he would run against incumbent Utah Governor Norm Bangerter in the Republican primary. Huntsman was leading in public opinion polls, sometimes by a double-digit margin. [ 36 ] He reportedly raised almost $300,000 in campaign advertising, returning all funds raised back to the donors. A few weeks later, Huntsman went on a 10-day business trip to Asia with his friend, U.S. Senator Jake Garn , who was chairman of Governor Bangerter's campaign. In mid-April Huntsman dropped out of the gubernatorial race and endorsed the governor, saying that party unity and his business responsibilities were more important than his political career, and asking political independents to support Bangerter. [ 37 ] [ 38 ] Later that year, Governor Bangerter appointed Huntsman to be the first Ambassador for Economic Development for the State of Utah. [ 21 ]
Huntsman's son, Jon Huntsman Jr. , served in the administrations of five U.S. Presidents, including Barack Obama (as U.S. Ambassador to China ) and most recently Donald Trump (as Ambassador to Russia ), and was a candidate for the 2012 Republican presidential nomination. [ 26 ]
There was considerable speculation that the viability of Jon Huntsman Jr.'s campaign might depend on Jon Huntsman Sr.'s willingness to fund advertising for it, via the Superpac "Our Destiny PAC". [ 39 ] Jon Huntsman Jr. reportedly downplayed the possibility of receiving campaign funding from his family before the New Hampshire primary election , telling NPR that "the Huntsman family gives to humanitarian causes and doesn't consider a political campaign to be a humanitarian cause". [ 40 ] However, reports filed with the Federal Election Commission later showed that Our Destiny PAC received $2.7 million in contributions, $1.9 million of it from Huntsman Sr. [ 41 ] [ 42 ] [ 43 ] Much of that money was spent on campaign ads, including $914,000 on campaign ads in New Hampshire in the two months before the January primary. [ 44 ]
Huntsman Sr. appeared on stage with Jon Huntsman Jr. and his wife and daughters at the third-place finish celebration in Manchester, New Hampshire . [ 45 ] Huntsman Jr. announced his intention in Manchester to continue the campaign in South Carolina [ 45 ] but dropped out on January 16, in advance of the vote there, throwing his support to Mitt Romney . [ 46 ]
Huntsman was widely recognized for his humanitarian giving which, including contributions to the homeless, the ill and the under-privileged, exceeds $1.5 billion and has assisted thousands, both domestically and internationally. [ 47 ] The Chronicle of Philanthropy placed Jon and Karen Huntsman second on their 2007 list of largest American donors. [ 48 ] On January 1, 2000, The Salt Lake Tribune included him among "The 10 Utahns Who Most Influenced Our State in the 20th Century" for his donations to education and medical research. [ 49 ] In 2001 Jon and Karen Huntsman were presented with the Entrepreneur of the Year Award for Principle-Centered Leadership. [ 50 ] In 2003 he received the Humanitarian of the Year Award, presented by Larry King of CNN. In November 2008, the American Cancer Society presented him its Medal of Honor for Cancer Philanthropy, [ 51 ] and in 2014 he was awarded the William E. Simon Prize for Philanthropic Leadership . [ 52 ] In 2015, he was awarded the Philanthropy Roundtable 's Carnegie Medal of Philanthropy Award. [ 53 ]
One of Huntsman's most notable causes is the Huntsman Cancer Institute (HCI) at the University of Utah, of which he was the founder and principal benefactor. He and his wife Karen established the Huntsman Cancer Institute in 1993 with a gift of $10 million from the Huntsman family. The Huntsmans gave the institute a further $100 million in 1995, an amount roughly equal to a year's total distribution to researchers from the American Cancer Society. [ 54 ] Their goal was to accelerate the work of curing cancer through human genetics. The institute is now one of America's major cancer research centers dedicated to finding a cure for cancer with a state-of-the-art cancer specialty hospital. [ 8 ] [ 32 ]
The Institute continues to receive substantial gifts from the Huntsman family. Huntsman, a cancer survivor, has stated "Except for my family and faith, there is no cause more important to me than fighting cancer ... I have committed the rest of my life to doing all I can to support clinical and research efforts to eliminate this disease." [ 55 ] To date, the Huntsman family and close associates have donated more than $656 million in support of the mission of HCI.
In November 2013, Huntsman donated or raised $120 million to Huntsman Cancer Institute at the University of Utah for the construction of a new research building dedicated to children's cancer. [ 56 ] The Primary Children's and Families' Cancer Research Center at Huntsman Cancer Institute was dedicated June 21, 2017, Huntsman's 80th birthday. [ 57 ]
Huntsman also promoted support of the institute through the Sigma Chi fraternity. Sigma Chi chose the Huntsman Cancer Foundation as one of its preferred philanthropic partners in December 2012. As of April 12, 2013, Sigma Chi had raised their first one-million dollars for cancer research. [ 58 ] [ 59 ] By 2017, Sigma Chi's total has reached over five million dollars for cancer research.
Huntsman had supported the University of Utah in Salt Lake City in other ways as well.
The 15,000-seat Jon M. Huntsman Center for special events opened in 1969 and is used for gymnastics, basketball, and volleyball. [ 60 ] It has been the site of national championships in both gymnastics [ 61 ] and basketball, including NCAA men's basketball. [ 62 ] As of 2013, the Huntsmans have supported the building of an additional basketball practice facility, to be named the Jon M. and Karen Huntsman Basketball Center. [ 63 ]
Huntsman has also given support to other universities. He has served as Chairman of the Board of Overseers of his alma mater, the Wharton School of the University of Pennsylvania , in Philadelphia, Pennsylvania. [ 64 ] One of the school's signature buildings, Jon Huntsman Hall, was named in his honor. Huntsman made an unrestricted gift of more than $50 million to Wharton, which was critical to development of the $140 million project. [ 65 ] As of 1994, the Huntsmans also endowed the Huntsman Program in International Studies and Business at the University of Pennsylvania, a four-year undergraduate program that combines business education and liberal arts. [ 66 ]
In 1989 Huntsman gave $1 million to Utah State University in Logan, Utah , for the Huntsman Environmental Research Center. At a press conference to announce the gift, Huntsman said the preservation of the environment is the single most important issue in the world. The Huntsmans also donated $500,000 to rebuild the Alumni Center, renamed the David B. Haight Alumni Center in honor of Mrs. Huntsman's father. [ 67 ] In December 2007, Utah State University announced that its College of Business would be renamed the Jon M. Huntsman School of Business , in recognition of a gift from Huntsman and his wife of $26 million, a major contributor for the new $40 million school of business building referred to as Huntsman Hall—the largest in the university's history to that time. [ 68 ] In 2017, Huntsman and Charles Koch donated another $50 million to the Huntsman School of Business for student scholarships and a new Center for Growth and Opportunity. [ 69 ]
The law library at Brigham Young University , built in 1975, was expanded and renamed for Howard W. Hunter in 1995 with financial support from Jon and Karen Huntsman and other donors. [ 70 ] A new library building at Southern Utah University , named in honor of retiring SUU President Gerald R. Sherratt, contains the Jon and Karen Huntsman Reading Room. [ 71 ] The Huntsmans also contributed to the Karen H. Huntsman Library in Snow College, Utah. Completed in 2010, it is a "green" building, expected to be the first academic library in the state to achieve gold Leadership in Energy and Environmental Design certification. [ 72 ] [ 73 ]
Huntsman has also contributed to efforts to rebuild in Armenia , which was devastated by an earthquake in 1988. He and other family members have made 46 trips to Armenia over 25 years. [ 74 ] He estimates that he has given at least $50 million to relief efforts in Armenia, including money to build schools and hospitals. [ 75 ] One of his earliest projects there involved setting up a plant to make pre-stressed concrete, to supply building materials for reconstruction and to employ Armenians. [ 74 ] The Huntsmans have built a tile roofing plant in Yerevan, [ 76 ] apartment complexes, and a K-12 school in the city of Gyumri. [ 74 ] [ 77 ] The Huntsmans also provide scholarships to bring Armenian students to America to study at Utah State University. [ 74 ] [ 78 ] Huntsman has been granted citizenship in the country and awarded two medals of honor by Armenia, one of them the St. Mesrop Mashtots Order . [ 74 ] [ 76 ]
Huntsman's donations of more than $1.2 billion overall dropped him from the " Forbes 400 " list as of 2010. His wealth was not disclosed; however, he was listed as number 937 on the "Forbes World's Richest Persons" for 2010. [ 79 ] He was one of only 19 of the world's 1,200 billionaires to have donated more than $1 billion. [ 47 ] He has said that he wants to "die broke" by giving his money away to various charities. [ 80 ]
Rocky Anderson , Democratic mayor of Salt Lake City , has said of Huntsman:
I was impressed with Jon from the first, when he told me he lost respect for Richard Nixon ... when he learned that Nixon had not given anything to charity one year he was president ... It was clear to me that Jon's real motivation in his work and accumulation of wealth was to give much of what he has to make people's lives better. [ 81 ]
Huntsman contributed to the resignation of the CEO of University of Utah Healthcare (HCI), Vivian Lee , after threatening to withhold $250 million in donations to the Huntsman Cancer Institute and attacking Lee's character in the public sphere. [ 88 ] [ 89 ] Lee resigned after the public backlash she received, particularly from editorials printed in the Salt Lake Tribune , a newspaper owned by the Huntsman family.
In an editorial, Huntsman described Lee as attempting a "power-grab", while Huntsman was attempting to sever HCI and University of Utah ties. [ 90 ] This controversy has raised the question of how much private donors should have a say in publicly funded healthcare. [ 91 ]
References: | https://en.wikipedia.org/wiki/Jon_Huntsman_Sr. |
Jonas Asevicius-Acus-Acukas (July 29, 1885 in Jieznas – July 11, 1976 in Kaunas ) was a Lithuanian army officer and chemist. From 1909 to 1918, he served in the Imperial Russian Army at Kaunas Fortress . He fought in the First World War and the Russian Civil War . In 1921 he returned to Lithuania and was mobilized into the Lithuanian Armed Forces , where he attained the rank of colonel (1927) and served until 1940. Acus graduated from Vytautas Magnus University in 1930. He lectured on chemistry and commodity science at Vytautas Magnus University (1934–1940), Vilnius University (1940–1950), and Lithuanian University of Agriculture (1951–1957). He wrote textbooks on foundations of commodity science (1949) and a short course in physical chemistry (1957). Acus was awarded the Commander's Crosses of the Order of Vytautas the Great (1938) and the Order of the Lithuanian Grand Duke Gediminas (1928).
This article about a Lithuanian scientist is a stub . You can help Wikipedia by expanding it .
This biographical article about a chemist is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jonas_Acus-Acukas |
The Jonathan Eberhart Planetary Sciences Journalism Award was established by the Division for Planetary Sciences to recognize and stimulate distinguished popular writing on planetary sciences. [ 1 ] The winning author (or authors) receives (or divide) a prize of $1,000, plus a citation. The award is named after science journalist Jonathan Eberhart . [ 2 ]
This journalism -related article is a stub . You can help Wikipedia by expanding it .
This science awards article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jonathan_Eberhart_Planetary_Sciences_Journalism_Award |
Jonathan Fishbein is an American physician and former director of the National Institutes of Health (NIH) Office for Policy in Clinical Research Operations. In 2005, Fishbein alleged that an NIH-funded clinical trial of the antiretroviral drug nevirapine , conducted in Africa, was invalid because of poor data collection, faulty record-keeping, and lax quality control. [ 1 ] The NIH subsequently attempted to fire Fishbein, and he sought protection as a whistleblower .
The clinical trial in question was the HIVNET 012 study, which tested the antiretroviral drug nevirapine , used in some developing countries as a cost-effective method to prevent transmission of HIV from mother to unborn child . [ 2 ] Fishbein was among several NIH employees to raise concerns about the study; he alleged that the NIH had become "so heavily invested in the trial's outcome" that it had lost objectivity about the quality of the result. [ 1 ] Internal NIH documents showed that concerns had been raised about HIVNET012, but that the Institute did not notify the Bush Administration before the launch of a major project to subsidize nevirapine use in Africa to combat the spread of HIV. [ 1 ] The NIH subsequently attempted to fire Fishbein; he alleged that the attempted dismissal was in retaliation for his complaints about HIVNET 012, while the agency cited poor performance during a probationary period as the cause for firing. [ 1 ]
In addition to his concerns about nevirapene, Fishbein also alleged that the drug was being improperly tested on foster children. He further complained that female staff at NIH were being sexually harassed. [ 3 ]
The NIH claim that Fishbein had underformed at his position was undermined by Fishbein having been recommended for a cash performance bonus mere weeks before the attempt to terminate him. [ 4 ]
In response to the allegations about nevirapene launched by Fishbein and others, the Institute of Medicine conducted an independent review of HIVNET 012 methodology and findings. The institute's review concluded that nevirapine was safe and effective in the prevention of mother-to-child HIV transmission, as HIVNET 012 had found, and that the study's methodology was sufficiently sound that scientists and policy-makers could rely on the study's findings. [ 5 ]
This biography of a person who has held a non-elected position in the federal government of the United States is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jonathan_Fishbein |
Jonathan David Sarfati (born 1 October 1964) is a young Earth creationist who writes articles for Creation Ministries International (CMI), a non-profit Christian apologetics ministry. Sarfati has a PhD in chemistry, and was New Zealand national chess champion in 1987 and 1988. [ 1 ] [ 2 ]
Born in Ararat , Victoria , Sarfati moved with his family to New Zealand as a child, where he became a dual Australian and New Zealand citizen. He attended Wellington College in New Zealand, later graduating from Victoria University of Wellington with a BSc (Hons.) in chemistry , and a PhD in the same subject for a thesis entitled "A Spectroscopic Study of some Chalcogenide Ring and Cage Molecules". He co-authored a paper on high-temperature superconductors that was published in Nature in 1987 ("Letters to Nature"), [ 3 ] and from 1988 to 1995, had five papers on spectroscopy of condensed matter samples published in other peer-reviewed scientific journals. [ 4 ] In 1996, he returned to Brisbane , Australia to work for the Creation Science Foundation , then Answers in Genesis , then its current name Creation Ministries International . In 2010, he moved to the American office of that ministry. [ 5 ]
Sarfati was a founder of the Wellington Christian Apologetics Society in New Zealand, and has long retained an interest in Christian apologetics and the creation–evolution controversy . [ 6 ] His first two books, Refuting Evolution in 1999, and Refuting Evolution 2 in 2002, are intended as rebuttals to the National Academy of Sciences ' publication Teaching about Evolution and the Nature of Science and the PBS / Nova series Evolution , respectively. Refuting Compromise , published in 2004, is Sarfati's rebuttal of the day-age creationist teachings of Hugh Ross , who attempts to harmonise the Genesis account of creation with mainstream science regarding the age of the Earth and the possible size of the Biblical Flood , against which Sarfati defends a literal biblical timeline and a global flood. Eugenie Scott and Glenn Branch of the National Center for Science Education called Sarfati's Refuting Evolution 2 a "crude piece of propaganda". [ 7 ]
Sarfati is a critic of geocentrism , [ 8 ] the Myth of the flat Earth [ 9 ] and flat Earth teaching, [ 10 ] homosexual behaviour, [ 11 ] and abortion [ 12 ] except to save the life of the mother. [ 13 ] While opposing embryonic stem cell research, he supports adult stem cell research. [ 14 ] Sarfati also supports vaccination and rebuts anti-vaccination arguments . [ 15 ]
Sarfati is a chess FIDE Master , and achieved a draw against former world champion Boris Spassky during a tournament in Wellington in 1988, [ 16 ] and was New Zealand's national chess champion in 1987–88. [ 17 ]
Although tied with Rey Casse for first place in the Australian Junior Championship of 1981, he was not eligible to share the title as he was a resident of New Zealand at the time. [ 18 ] He represented New Zealand in three Chess Olympiads : the 27th in Dubai [ 19 ] in 1986, the 28th in Thessaloniki [ 20 ] in 1988, and the 30th in Manila [ 21 ] in 1992. He also represented New Zealand on top board at the 5th Asian Teams in New Delhi . [ 22 ]
He has given blindfold chess exhibitions at chess clubs [ 23 ] and other events, [ 24 ] [ 25 ] [ 26 ] and has played twelve such games simultaneously. [ 27 ] His previous best was winning 11/11 at the Kāpiti Chess Club in New Zealand. [ 28 ] | https://en.wikipedia.org/wiki/Jonathan_Sarfati |
The Jones oxidation is an organic reaction for the oxidation of primary and secondary alcohols to carboxylic acids and ketones , respectively. It is named after its discoverer, Sir Ewart Jones . The reaction was an early method for the oxidation of alcohols. Its use has subsided because milder, more selective reagents have been developed, e.g. Collins reagent . [ 1 ]
Jones reagent is a solution prepared by dissolving chromium trioxide in aqueous sulfuric acid . To effect a Jones oxidation, this acidic mixture is then added to an acetone solution of the substrate. Alternatively, potassium dichromate can be used in place of chromium trioxide. The oxidation is very rapid and quite exothermic . Yields are typically high. The reagent is convenient and cheap. However, Cr(VI) compounds are carcinogenic, which deters the use of this methodology.
Jones reagent will convert primary and secondary alcohols to aldehydes and ketones, respectively. Depending on the reaction conditions, the aldehydes may then be converted to carboxylic acids. For oxidations to the aldehydes and ketones, two equivalents of chromic acid oxidize three equivalents of the alcohol:
For oxidation of primary alcohols to carboxylic acids, 4 equivalents of chromic acid oxidize 3 equivalents of the alcohol. The aldehyde is an intermediate.
The inorganic products are green, characteristic of chromium(III) aquo complexes . [ 2 ]
Like many other oxidations of alcohols by metal oxides, the reaction proceeds via the formation of a mixed chromate ester : [ 3 ] [ 4 ] These esters have the formula CrO 3 (OCH 2 R) −
Like conventional esters, the formation of this chromate ester is accelerated by the acid. These esters can be isolated when the alcohol is tertiary because these lack the α hydrogen that would be lost to form the carbonyl. For example, using tert -butyl alcohol , one can isolate tert -butyl chromate ((CH 3 ) 3 CO) 2 CrO 2 ), which is itself a good oxidant. [ 5 ]
For those structures with hydrogen alpha to the oxygen, the chromate esters degrade, releasing the carbonyl product and an ill-defined Cr(IV) product:
The deuterated alcohols HOCD 2 R oxidize about six times slower than the undeuterated derivatives. This large kinetic isotope effect shows that the C–H (or C–D) bond breaks in the rate-determining step .
The reaction stoichiometry implicates the Cr(IV) species "CrO 2 OH − ", which comproportionates with the chromic acid to give a Cr(V) oxide, which also functions as an oxidant for the alcohol. [ 6 ]
The oxidation of the aldehydes is proposed to proceed via the formation of hemiacetal -like intermediates, which arise from the addition of the O 3 CrO-H − bond across the C=O bond.
The reagent rarely oxidizes unsaturated bonds. In certain cases, depending on very
exact stereoelectronic factors, production of epoxides may occur.
It remains useful in organic synthesis . [ 2 ] [ 7 ] A variety of spectroscopic techniques, including infrared spectroscopy , can be used to monitor the progress of a Jones oxidation reaction. At one time the Jones oxidation was used in breathalyzers .
The other principal alcohol oxidation processes utilize Collins reagent, Cornforth reagent , and PCC . Many of these reagents represent improvements over inorganic chromium(VI) reagents such as Jones reagent with respect to selectivity , specifically in increased favorablility of oxidizing primary alcohols to aldehydes over carboxylic acids. [ 8 ] | https://en.wikipedia.org/wiki/Jones_oxidation |
The Jones oxidation is an organic reaction for the oxidation of primary and secondary alcohols to carboxylic acids and ketones , respectively. It is named after its discoverer, Sir Ewart Jones . The reaction was an early method for the oxidation of alcohols. Its use has subsided because milder, more selective reagents have been developed, e.g. Collins reagent . [ 1 ]
Jones reagent is a solution prepared by dissolving chromium trioxide in aqueous sulfuric acid . To effect a Jones oxidation, this acidic mixture is then added to an acetone solution of the substrate. Alternatively, potassium dichromate can be used in place of chromium trioxide. The oxidation is very rapid and quite exothermic . Yields are typically high. The reagent is convenient and cheap. However, Cr(VI) compounds are carcinogenic, which deters the use of this methodology.
Jones reagent will convert primary and secondary alcohols to aldehydes and ketones, respectively. Depending on the reaction conditions, the aldehydes may then be converted to carboxylic acids. For oxidations to the aldehydes and ketones, two equivalents of chromic acid oxidize three equivalents of the alcohol:
For oxidation of primary alcohols to carboxylic acids, 4 equivalents of chromic acid oxidize 3 equivalents of the alcohol. The aldehyde is an intermediate.
The inorganic products are green, characteristic of chromium(III) aquo complexes . [ 2 ]
Like many other oxidations of alcohols by metal oxides, the reaction proceeds via the formation of a mixed chromate ester : [ 3 ] [ 4 ] These esters have the formula CrO 3 (OCH 2 R) −
Like conventional esters, the formation of this chromate ester is accelerated by the acid. These esters can be isolated when the alcohol is tertiary because these lack the α hydrogen that would be lost to form the carbonyl. For example, using tert -butyl alcohol , one can isolate tert -butyl chromate ((CH 3 ) 3 CO) 2 CrO 2 ), which is itself a good oxidant. [ 5 ]
For those structures with hydrogen alpha to the oxygen, the chromate esters degrade, releasing the carbonyl product and an ill-defined Cr(IV) product:
The deuterated alcohols HOCD 2 R oxidize about six times slower than the undeuterated derivatives. This large kinetic isotope effect shows that the C–H (or C–D) bond breaks in the rate-determining step .
The reaction stoichiometry implicates the Cr(IV) species "CrO 2 OH − ", which comproportionates with the chromic acid to give a Cr(V) oxide, which also functions as an oxidant for the alcohol. [ 6 ]
The oxidation of the aldehydes is proposed to proceed via the formation of hemiacetal -like intermediates, which arise from the addition of the O 3 CrO-H − bond across the C=O bond.
The reagent rarely oxidizes unsaturated bonds. In certain cases, depending on very
exact stereoelectronic factors, production of epoxides may occur.
It remains useful in organic synthesis . [ 2 ] [ 7 ] A variety of spectroscopic techniques, including infrared spectroscopy , can be used to monitor the progress of a Jones oxidation reaction. At one time the Jones oxidation was used in breathalyzers .
The other principal alcohol oxidation processes utilize Collins reagent, Cornforth reagent , and PCC . Many of these reagents represent improvements over inorganic chromium(VI) reagents such as Jones reagent with respect to selectivity , specifically in increased favorablility of oxidizing primary alcohols to aldehydes over carboxylic acids. [ 8 ] | https://en.wikipedia.org/wiki/Jones_reagent |
A Jones reductor is a device used to reduce aqueous solutions of metal ions. The active component is a zinc amalgam . [ 1 ] Jones reductors have been used for preparing solutions of titanium (III), vanadium (II), chromium (II), molybdenum (III), niobium (III), europium (II), and uranium (III).
Amalgamated zinc is prepared by treating zinc metal with a 2% solution of mercury(II) chloride . The metal may be in the granulated form or as shavings, wool, or powder. The amalgam forms on the surface of the zinc. After washing to remove salts, the amalgam is placed in a long glass tube, similar to a chromatography column , equipped with a stopcock. [ 1 ] The amalgam is a more effective reducing agent than zinc metal. The effluent is often air-sensitive, requiring the use of air-free techniques .
To use the reductor, the solution to be reduced is drawn through the tube. If the column is loosely packed, the solution may pass through without assistance. The length of the column or the flow rate are adjusted to effect full reduction of the soluble reagent. The effluent is also contaminated with zinc(II) salts, but they do not affect subsequent operations. These operations might include iodometric titration to determine the reducible content of the effluent. In some cases, the effluent is treated with other reagents to precipitate a compound of the reduced ions. [ 2 ] [ 3 ] | https://en.wikipedia.org/wiki/Jones_reductor |
Jonesia is a genus of Actinomycetota . [ 1 ] [ 2 ]
This Actinomycetota -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jonesia |
Jonesiaceae is a family of Actinomycetota . [ 1 ] [ 2 ]
This Actinomycetota -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jonesiaceae |
The Jones–Dole equation , or Jones–Dole expression, is an empirical expression that describes the relationship between the viscosity of a solution and the concentration of solute within the solution (at a fixed temperature and pressure). [ 1 ] The Jones–Dole equation is written as [ 2 ] η η 0 = 1 + A C 1 2 + B C , {\displaystyle {\frac {\eta }{\eta _{0}}}=1+AC^{\frac {1}{2}}+BC,} where
The Jones–Dole B coefficient [ 3 ] is often used to classify ions as either structure-makers (kosmotropes) or structure-breakers ( chaotropes ) according to their supposed strengthening or weakening of the hydrogen-bond network of water . [ 4 ] [ 5 ] The Jones–Dole expression works well up to about 1 M, but at higher concentrations breaks down, as the viscosity of all solutions increase rapidly at high concentrations.
The large increase in viscosity as a function of solute concentration seen in all solutions above about 1 M is the effect of a jamming transition at a high concentration. As a result, the viscosity increases exponentially as a function of concentration and then diverges at a critical concentration. This has been referred to as the "Mayonnaise effect", [ 6 ] as the viscosity of mayonnaise (essentially a solution of oil in water) is extremely high because of the jamming of micrometer-scale droplets.
This physical chemistry -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jones–Dole_equation |
Jong-Soo Rhyee is a South Korean physicist and materials scientist . He is a professor in the Department of Applied Physics at the Applied Science College of Kyung Hee University [ 1 ] and serves as the Outside Director at KPT, the Representative CEO of V-memory, and the CTO of R-Materials in South Korea. [ 2 ]
Rhyee's research spans across domains of material science, encompassing magnetic and energy materials , crystal growth , thermoelectric materials , high thermal conductivity materials, magneto-caloric effect materials, unconventional properties of oxides and intermetallics , and superconductivity . He is the recipient of the 2009 Young Investigator Award by the International Thermoelectric Society [ 3 ] and the 2018 IAAM Scientist Medal by the International Association of Advanced Materials. [ 4 ]
Rhyee holds 19 Korean patents along with 32 international patents. [ 5 ] [ 6 ] [ 7 ]
Rhyee obtained his Bachelor's in Physics from Chung-buk National University in 1998, and a Master's in Experimental Solid-State Physics from Pohang University of Science and Technology (POSTECH) in 2000 under advisor Sung Ik Lee. He pursued a Ph.D. in Magnetic Materials at Gwangju Institute of Science and Technology (GIST) from 2000 to 2005, researching Hexaboride compounds under advisor Beong Ki Cho. [ 8 ]
Rhyee worked as a Postdoc Researcher in the Crystal Growth group at Max Planck Institute for Solid State Research in Germany from April 2006 to April 2007 [ 9 ] and then served as an R&D Staff Researcher at the Materials Research Lab at Samsung Advanced Institute of Technology (SAIT) from May 2007 to August 2010. [ 10 ] He moved into academia as an assistant professor at the Department of Applied Physics of the Applied Science College at Kyung Hee University in South Korea in 2010, becoming associate professor in 2014 and Professor in 2019 [ 11 ]
While in the role of associate professor, Rhyee concurrently held the position of department chair for the Department of Applied Physics from March 2017 to February 2019, and as the Vice Dean of the Applied Science College at Kyung Hee University from March 2018 to February 2019. He has been serving as the Outside Director at KPT since June 2022, as well as the CTO at R-Materials in South Korea since January 2023, and has also been acting as the Representative CEO of V-memory in South Korea since January 2020. [ 2 ]
Rhyee's research has focused on developing new materials in fields such as magnetic, superconductivity, and energy materials. He has investigated crystal growth in intermetallic and oxide compounds, studied thermoelectric materials for waste heat recovery and high thermal conductive materials for electronic applications. Additionally, his research has encompassed magneto-caloric effect materials for solid-state cooling, unconventional properties of oxides and intermetallics, and quasi-one-dimensional electronic transport. He has also explored soft magnetic materials, topological and Weyl semimetallic system, and superconductivity. [ 12 ]
During his time at SAIT's Materials Research Center, Rhyee developed high-performance thermoelectric materials In 4 Se 3−δ , published in Nature on 2009. This research proposed an approach to enhance ZT thermoelectric materials through Peierls distortion. [ 13 ] He provided both experimental evidence and theoretical insights demonstrating that alloying SnTe with Ca significantly improved its transport properties, leading to a ZT of 1.35 at 873 K, the highest reported ZT value for singly doped SnTe materials. The study predicted approximately 10% efficiency for high-temperature thermoelectric power generation using SnTe-based materials, assuming a 400 K temperature difference. [ 14 ] Furthermore, his work enhanced the thermoelectric properties of In 4 Se 3–x Cl 0.03 bulk crystals through Ca alloying, [ 15 ] and showed that intercalation of Cu nanoparticles between Te layers in Bi 2 Te 3 transforms its native p-type character to n-type, reducing thermal conductivity and enhancing thermoelectric performance with a figure of merit (ZT) of 1.15 at approximately 300 K. [ 16 ] His research also addressed the development of high-mobility transistors using CVD-grown MoSe 2 films for applications like high-resolution displays. [ 17 ]
Within his magnetism and thermoelectric research, Rhyee has explored unconventional magnetism in boride and intermetallic compounds, with a focus on magnetic polaronic transport and correlated properties. He examined the link between topological states and thermoelectricity, discovering that the topological phase transition in Dirac semimetals boosts thermoelectric performance. Further investigations revealed that selective charge Anderson localization is a novel avenue for enhancing thermoelectricity, yielding a ZT value of 2.0 in n-type thermoelectric power generation. [ 18 ] In a collaborative work, he presented a novel magnetic field-induced type II Weyl semimetallic state in the Shastry-Sutherland lattice, characterized by non-trivial Berry phase, magnetic field-induced Weyl nodes and spin chirality, chiral anomaly, anomalous magnetoconductivity, and demonstrated topological phase evolution. [ 19 ] | https://en.wikipedia.org/wiki/Jong-Soo_Rhyee |
Jongla is a Finnish start-up company, specialising mobile messaging apps. In June 2016, Jongla announced that it wants to bridge the gap between social networking services and messaging apps. [ 1 ] Jongla is targeting especially emerging markets like Africa , Southeast Asia and South America , where they are seeing the best traction. [ 2 ] [ 3 ] [ 4 ] Jongla app is available on Android , [ 5 ] iOS [ 6 ] and Windows Phone [ 7 ] platforms .
In June, 2016 Jongla introduced their 3rd generation app, the Jongla - Social Messenger, which introduced feature updates, brand upgrade and a new app UI. In Social Messenger, Jongla introduced the community of nearby Jongla users and an added ability to engage with user profiles with a choice of reaction like thumbs-up, smile or heart.
Jongla claims to be the world's lightest instant messaging app . The company backs up their claim with app package size comparisons. In June 2016, their APK (Android Application Package) size was 3.5MB, being one tenth of that compared to their competitor apps like WhatsApp, Messenger and Viber. [ 8 ]
Jongla has the basic messaging functions like private and group chats and sharing text, stickers, images, locations and videos. Also, anyone can join a Jongla conversation via web application called Jongla Out. Jongla is one of the few messaging apps offering voice messages with special filters which is an integrated push-to-talk voice messaging feature with access to a range of funny voice filters that alter sender's voice. [ 9 ]
Jongla has been selected as a winner of the Red Herring's Top 100 Global award 2013. [ 10 ] The company has been featured in articles by Forbes , [ 11 ] CNBC Africa , [ 12 ] Mobile Industry Review [ 13 ] and The Guardian Nigeria .
Jongla is a Finland-based company founded by Arto Boman and headquartered in Helsinki , Finland . [ 14 ] Jongla CSO is Riku Salminen and the company is owned by a group of private investors including JSH Capital Oy, Ingman Finance Oy, and Holdington Ltd Oy. [ 15 ] Chairman of the board is Henry Sjöman accompanied with board members Arto Boman and Simo Makkonen. [ 16 ] | https://en.wikipedia.org/wiki/Jongla |
In relativistic quantum mechanics and quantum field theory , the Joos–Weinberg equation is a relativistic wave equation applicable to free particles of arbitrary spin j , an integer for bosons ( j = 1, 2, 3 ... ) or half-integer for fermions ( j = 1 ⁄ 2 , 3 ⁄ 2 , 5 ⁄ 2 ... ). The solutions to the equations are wavefunctions , mathematically in the form of multi-component spinor fields . The spin quantum number is usually denoted by s in quantum mechanics, however in this context j is more typical in the literature (see references ).
It is named after Hans H. Joos and Steven Weinberg , found in the early 1960s. [ 1 ] [ 2 ] [ 3 ]
Introducing a 2(2 j + 1) × 2(2 j + 1) matrix; [ 2 ]
symmetric in any two tensor indices, which generalizes the gamma matrices in the Dirac equation, [ 3 ] [ 4 ] the equation is [ 5 ]
or
[ γ μ 1 μ 2 ⋯ μ 2 j P μ 1 P μ 2 ⋯ P μ 2 j + ( m c ) 2 j ] Ψ = 0 {\displaystyle [\gamma ^{\mu _{1}\mu _{2}\cdots \mu _{2j}}P_{\mu _{1}}P_{\mu _{2}}\cdots P_{\mu _{2j}}+(mc)^{2j}]\Psi =0}
For the JW equations the representation of the Lorentz group is [ 6 ]
This representation has definite spin j . It turns out that a spin j particle in this representation satisfy field equations too. These equations are very much like the Dirac equations. It is suitable when the symmetries of charge conjugation , time reversal symmetry , and parity are good.
The representations D ( j , 0) and D (0, j ) can each separately represent particles of spin j . A state or quantum field in such a representation would satisfy no field equation except the Klein–Gordon equation.
The six-component spin-1 representation space,
can be labeled by a pair of anti-symmetric Lorentz indexes, [ αβ ] , meaning that it transforms as an antisymmetric Lorentz tensor of second rank B [ α β ] , {\displaystyle B_{[\alpha \beta ]},} i.e.
The j -fold Kronecker product T [ α 1 β 1 ]...[ α j β j ] of B [ αβ ]
decomposes into a finite series of Lorentz-irreducible representation spaces according to
and necessarily contains a D ( j , 0 ) ⊕ D ( 0 , j ) {\displaystyle D^{(j,0)}\oplus D^{(0,j)}} sector. This sector can instantly be identified by means of a momentum independent projector operator P ( j ,0) , designed on the basis of C (1) , one of the Casimir elements (invariants) [ 7 ] of the Lie algebra of the Lorentz group , which are defined as,
where M μν are constant (2 j 1 +1)(2 j 2 +1) × (2 j 1 +1)(2 j 2 +1) matrices defining the elements of the Lorentz algebra within the D ( j 1 , j 2 ) ⊕ D ( j 2 , j 1 ) {\displaystyle D^{(j_{1},j_{2})}\oplus D^{(j_{2},j_{1})}} representations. The Capital Latin letter labels indicate [ 8 ] the finite dimensionality of the representation spaces under consideration which describe the internal angular momentum ( spin ) degrees of freedom.
The representation spaces D ( j 1 , j 2 ) ⊕ D ( j 2 , j 1 ) {\displaystyle D^{(j_{1},j_{2})}\oplus D^{(j_{2},j_{1})}} are eigenvectors to C (1) in ( 8B ) according to,
Here we define:
to be the C (1) eigenvalue of the D ( j 1 , j 2 ) ⊕ D ( j 2 , j 1 ) {\displaystyle D^{(j_{1},j_{2})}\oplus D^{(j_{2},j_{1})}} sector. Using this notation we define the projector operator, P ( j ,0) in terms of C (1) : [ 8 ]
Such projectors can be employed to search through T [ α 1 β 1 ]...[ α j β j ] for D ( j , 0 ) ⊕ D ( 0 , j ) , {\displaystyle D^{(j,0)}\oplus D^{(0,j)},} and exclude all the rest. Relativistic second order wave equations for any j are then straightforwardly obtained in first identifying the D ( j , 0 ) ⊕ D ( 0 , j ) {\displaystyle D^{(j,0)}\oplus D^{(0,j)}} sector in T [ α 1 β 1 ]...[ α j β j ] in ( 8A ) by means of the Lorentz projector in ( 8C ) and then imposing on the result the mass shell condition.
This algorithm is free from auxiliary conditions. The scheme also extends to half-integer spins, s = j + 1 2 {\displaystyle s=j+{\tfrac {1}{2}}} in which case the Kronecker product of T [ α 1 β 1 ]...[ α j β j ] with the Dirac spinor,
has to be considered. The choice of the totally antisymmetric Lorentz tensor of second rank, B [ α i β i ] , in the above equation ( 8A ) is only optional. It is possible to start with multiple Kronecker products of totally symmetric second rank Lorentz tensors, A α i β i . The latter option should be of interest in theories where high-spin D ( j , 0 ) ⊕ D ( 0 , j ) {\displaystyle D^{(j,0)}\oplus D^{(0,j)}} Joos–Weinberg fields preferably couple to symmetric tensors, such as the metric tensor in gravity.
Source: [ 8 ]
The
transforming in the Lorenz tensor spinor of second rank,
The Lorentz group generators within this representation space are denoted by [ M μ ν A T S ] [ α β ] [ γ δ ] , {\displaystyle \left[M_{\mu \nu }^{ATS}\right]_{[\alpha \beta ][\gamma \delta ]},} and given by:
where 1 [ αβ ][ γδ ] stands for the identity in this space, 1 S and M S μν are the respective unit operator and the Lorentz algebra elements within the Dirac space, while γ μ are the standard gamma matrices . The [ M AT μν ] [ αβ ][ γδ ] generators express in terms of the generators in the four-vector,
as
Then, the explicit expression for the Casimir invariant C (1) in ( 8B ) takes the form,
and the Lorentz projector on (3/2,0)⊕(0,3/2) is given by,
In effect, the (3/2,0)⊕(0,3/2) degrees of freedom, denoted by
are found to solve the following second order equation,
Expressions for the solutions can be found in. [ 8 ] | https://en.wikipedia.org/wiki/Joos–Weinberg_equation |
In mathematics, Jordan's inequality , named after Camille Jordan , states that [ 1 ]
It can be proven through the geometry of circles (see drawing). [ 2 ] | https://en.wikipedia.org/wiki/Jordan's_inequality |
In complex analysis , Jordan's lemma is a result frequently used in conjunction with the residue theorem to evaluate contour integrals and improper integrals . The lemma is named after the French mathematician Camille Jordan .
Consider a complex -valued, continuous function f , defined on a semicircular contour
of positive radius R lying in the upper half-plane , centered at the origin. If the function f is of the form
with a positive parameter a , then Jordan's lemma states the following upper bound for the contour integral:
with equality when g vanishes everywhere, in which case both sides are identically zero. An analogous statement for a semicircular contour in the lower half-plane holds when a < 0 .
Jordan's lemma yields a simple way to calculate the integral along the real axis of functions f ( z ) = e i a z g ( z ) holomorphic on the upper half-plane and continuous on the closed upper half-plane, except possibly at a finite number of non-real points z 1 , z 2 , …, z n . Consider the closed contour C , which is the concatenation of the paths C 1 and C 2 shown in the picture. By definition,
Since on C 2 the variable z is real, the second integral is real:
The left-hand side may be computed using the residue theorem to get, for all R larger than the maximum of | z 1 | , | z 2 | , …, | z n | ,
where Res( f , z k ) denotes the residue of f at the singularity z k . Hence, if f satisfies condition ( * ), then taking the limit as R tends to infinity, the contour integral over C 1 vanishes by Jordan's lemma and we get the value of the improper integral
The function
satisfies the condition of Jordan's lemma with a = 1 for all R > 0 with R ≠ 1 . Note that, for R > 1 ,
hence ( * ) holds. Since the only singularity of f in the upper half plane is at z = i , the above application yields
Since z = i is a simple pole of f and 1 + z 2 = ( z + i )( z − i ) , we obtain
so that
This result exemplifies the way some integrals difficult to compute with classical methods are easily evaluated with the help of complex analysis.
This example shows that Jordan's lemma can be used instead of a much simpler estimation lemma . Indeed, estimation lemma suffices to calculate ∫ − ∞ ∞ e i x 1 + x 2 d x {\displaystyle \int _{-\infty }^{\infty }{\frac {e^{ix}}{1+x^{2}}}\,dx} , as well as ∫ − ∞ ∞ cos x 1 + x 2 d x {\displaystyle \int _{-\infty }^{\infty }{\frac {\cos x}{1+x^{2}}}\,dx} , Jordan's lemma here is unnecessary.
By definition of the complex line integral ,
Now the inequality
yields
Using M R as defined in ( * ) and the symmetry sin θ = sin( π − θ ) , we obtain
Since the graph of sin θ is concave on the interval θ ∈ [0, π ⁄ 2] , the graph of sin θ lies above the straight line connecting its endpoints, hence
for all θ ∈ [0, π ⁄ 2] , which further implies | https://en.wikipedia.org/wiki/Jordan's_lemma |
Jordan's rule (sense 1) is an ecogeographical rule that describes the inverse relationship between water temperature and meristic characteristics in various species of fish . The most commonly observed relationship is that fin ray , vertebrae , or scale numbers increase with decreasing temperature. The rule is named after David Starr Jordan (1851–1931), the father of American ichthyology . [ 1 ]
Jordan's law (or rule) (sense 2) is also an ecogeographical rule (named after the same scientist) that states: "‘[g]iven any species in any region, the nearest related species is not likely to be found in the same region nor in a remote region, but in a neighbouring district separated from the first by a barrier of some sort’ [ 2 ] This "rule" is frequently violated (see discussion in Fitzpatrick & Turelli 2007 [ 3 ] ), but when patterns are consistent with Jordan's rule (sense 2), this suggests an important role for allopatric speciation in the diversification of the clade in question. [ 4 ] [ 5 ] Jordan himself wrote: "To this generalization Dr. Allen , in a late number of Science, gives the name of 'Jordan's Law.' The present writer makes no claim to the discovery of this law. The language above quoted is his, but the idea is familiar to all students of geographical distribution and goes back to the master in that field, Moritz Wagner ." [ 6 ] [ 7 ] Thus, Jordan's law is an example of Stigler's law . | https://en.wikipedia.org/wiki/Jordan's_rule |
In number theory , Jordan's totient function , denoted as J k ( n ) {\displaystyle J_{k}(n)} , where k {\displaystyle k} is a positive integer, is a function of a positive integer , n {\displaystyle n} , that equals the number of k {\displaystyle k} - tuples of positive integers that are less than or equal to n {\displaystyle n} and that together with n {\displaystyle n} form a coprime set of k + 1 {\displaystyle k+1} integers.
Jordan's totient function is a generalization of Euler's totient function , which is the same as J 1 ( n ) {\displaystyle J_{1}(n)} . The function is named after Camille Jordan .
For each positive integer k {\displaystyle k} , Jordan's totient function J k {\displaystyle J_{k}} is multiplicative and may be evaluated as
The first two formulas were discovered by Jordan. | https://en.wikipedia.org/wiki/Jordan's_totient_function |
Jordan Phosphate Mines ( JPMC ) is a mining company based in Amman , Jordan . The company operates 3 mining facilities in Jordan and a chemical manufacturing complex in Aqaba . The company is listed on the Amman Stock Exchange 's ASE Weighted Index as "JOPH".
Jordan Phosphate Mines was founded in 1949.
In 1986, JPMC bought the Jordan Fertilizer Company . JPMC already controlled 25% of the fertilizing company before its full acquisition. Jordan Fertilizer was operating a chemical and fertilizer manufacturing complex in Aqaba , which became the property of JPMC.
In 2007, JPMC signed a memorandum of understanding with the Indian Farmers Fertiliser Cooperative (IFFCO), India's largest fertilizer manufacturer. In 2013, the partnership was renewed for one year, committing JPMC to deliver 2 million tonnes of phosphate in a year.
In the first semester of 2014, JPMC recorded a net loss of $9.4 million, mainly due to lower commodity prices and higher fuel costs. [ 1 ]
In April 2016, JPMC raised JD82.5 million. [ 2 ] In February 2017, JPMC signed a memorandum of understanding with the government of Bangladesh to provide the country with 270,000 metric tonnes of phosphate and phosphoric acid within 3 years for $280 million. [ 3 ] In May 2018, IFFCO and Indian Potash Limited (IPL) bought a 37% share in JPMC from the Brunei Investment Agency for $130 million. [ 4 ] 60% of JPMC's production was already exported to india by the time of this purchase. [ 5 ]
According to the company's website, more than 60% of the area of Jordan has phosphate deposits at minable depth. JPMC is the only phosphate-mining company in Jordan. JPMC's three mining facilities are located in:
JPMC's al-Aqaba complex produces fertilizer and chemicals, including:
JPMC runs the Indo-Jordan Chemicals , co-owned with Southern Petrochemical Industries of India and The Arab Investment Company of Saudi Arabia .
JPMC runs the Nippon Jordan Fertilizer Company , a joint venture with the Arab Potash Company and a consortium of Japanese companies ( ZEN-NOH , Mitsubishi Corporation , Mitsubishi Chemical , Asahi Kasei ).
JPMC runs the PT Petro Jordan Abadi , a joint venture with the Indonesian company Petrokimia Gresik . [ 7 ]
In June 2013, the uncle of the King of Jordan, Walid Kurdi, was found guilty of illegally profiting by using his position of CEO of JPMC. The justice fined him JD284 million. [ 8 ] In August 2017, JPMC filed for an arrest warrant with Interpol to extradite Walid Kurdi who fled the country and was living as a fugitive. [ 9 ] | https://en.wikipedia.org/wiki/Jordan_Phosphate_Mines |
The Jordan Valley Unified Water Plan , commonly known as the " Johnston Plan ", was a plan for the unified water resource development of the Jordan Valley . It was negotiated and developed by United States Special Representative Eric Johnston between 1953 and 1955, and based on an earlier plan commissioned by United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA). Modeled upon the Tennessee Valley Authority 's engineered development plan, it was approved by technical water committees of all the regional riparian countries— Israel , Jordan , Lebanon and Syria . [ 1 ] Though the plan was rejected by the Arab League, both Israel and Jordan undertook to abide by their allocations under the plan. The US provided funding for Israel's National Water Carrier after receiving assurances from Israel that it would continue to abide by the plan's allocations. [ 2 ] Similar funding was provided for Jordan's East Ghor Main Canal project after similar assurances were obtained from Jordan. [ 3 ]
In the late 1930s and mid 1940s, Transjordan and the Zionist Organization commissioned mutually exclusive, competing water resource development studies. The Transjordanian study, performed by Michael G. Ionides, concluded that the naturally available water resources were not sufficient to sustain a Jewish homeland and the destination of Jewish immigrants. The Zionist's study, by the American engineer Walter Clay Lowdermilk concluded similarly, but noted that by diverting water from the Jordan River basin to the Negev for support of agricultural and residential development there, a Jewish state with 4 million new immigrants would be sustainable. [ 4 ]
In 1953, Israel began construction of a water carrier to take water from the Sea of Galilee to the populated center and agricultural south of the country, while Jordan concluded an agreement with Syria, known as the Bunger plan, to dam the Yarmouk river near Maqarin, and utilize its waters to irrigate Jordanian territory, before they could flow to the Sea of Galilee. [ 5 ] Military clashes ensued, and US President Dwight Eisenhower dispatched ambassador Johnston to the region to work out a plan that would regulate water usage. [ 6 ]
Source: [ 7 ]
Banat Yacov Project. 7 February 1956:
I. Next foreseeable crisis date in Arab-Israeli situation comes on 1 March, the "deadline" date which Israelis gave Amb. Johnston last autumn for gaining Arab acceptance of Jordan river valley scheme. After 1 March, Israelis told Johnston, they would feel free to go ahead with unilateral Israeli plan for using Jordan Waters.
II. Bone of contention is so-called Banat Yacov project, which takes its name from bridge crossing Jordan River some 8 mi. north of Lake Tiberias (Sea of Galilee).
III. Question came to UN Security Council shortly after Israelis began work on project over two years ago. (Sep '53).
IV. However, Israelis have made their "postponement" of Banat Yacov completion contingent on implementation of Johnston plan.
V. On 31 Jan, Syrian prime minister Ghazzi delivered aide memoirs to US embassy which implied that Syria would use force to prevent Israelis from resuming work on that part of Banat Yacov canal which lies in "demilitarized zone."
VI. However, Israelis have given intimations recently that "deadline" does not necessarily mean they will resume Banat Yacov work on or immediately after 1 March.
UN Sec. Gen Hammarskjold after visit to Palestine in January told American officials he felt Banat Yacov issue Syria would fight on. he felt Israel wrong if forced this issue and he and Gen. Burns agreed they would take strong stand against unilateral action by Israel at Banat Yacov. [ 8 ]
Eisenhower appointed Eric Johnston as a special ambassador on 16 October 1953, and tasked him with mediating a comprehensive plan for the regional development of the Jordan River system. [ 9 ] As a starting point, Johnston used a plan commissioned by UNRWA and performed by the American consulting firm Chas. T. Main , known as the "Main Plan". The Main Plan, published just days before Johnston's appointment, utilized the same principles employed by the Tennessee Valley Authority to optimize the usage of an entire river basin as a single unit. [ 10 ]
The plan was based on principles similar to those embodied in the Marshall Plan – reducing the potential for conflict by promoting cooperation and economic stability. [ 9 ]
The main features of the plan were:
The initial plan gave preference to in-basin use of the Jordan waters, and ruled out integration of the Litani River in Lebanon. The proposed quotas were: Israel 394 million m³, Jordan 774 million m³, and Syria 45 million m³.
Both sides countered with proposals of their own. Israel demanded the inclusion of the Litani river in the pool of available sources, the use of the Sea of Galilee as the main storage facility, out-of-basin use of the Jordan waters, and the Mediterranean-Dead Sea canal. As well, Israel demanded more than doubling of its allocation, from 394 million m³ annually to 810 million m³.
The Arabs countered with a proposal based on the Ionides, MacDonald and Bunger plans, meaning exclusive in-basin use, and rejecting storage in the Sea of Galilee. As well, they demanded recognition of Lebanon as a riparian state, while excluding the Litani from the plan. Their proposed quota allocations were: Israel 200 million m³, Jordan 861 million m³, Syria 132 million m³ and Lebanon 35 million m³ per year.
Negotiations ensued, and gradually the differences were eliminated. Israel dropped the request to integrate the Litani, and the Arabs dropped their objection to out-of-basin use of waters. Ultimately the unified plan proposed the following allocations, by source:
The Plan was accepted by the technical committees from both Israel and the Arab League . A discussion in the Knesset in July 1955 ended without a vote. The Arab Experts Committee approved the plan in September 1955 and referred it for final approval to the Arab League Council. On 11 October 1955, the Council voted not to ratify the plan, due to the League's opposition to formal recognition of Israel. However, the Arab League committed itself to adhere to the technical details without providing official approval. [ 9 ]
After the Suez Crisis in 1956, however, Arab attitudes hardened considerably, [ 12 ] and the Arab League, with the exception of Jordan, now actively opposed the Johnston plan, arguing that any plan to strengthen the Israeli economy only increased the potential threat from Israel. [ 13 ] Regardless, both Jordan and Israel undertook to operate within their allocations, and two major successful projects were completed – the Israeli National Water Carrier and Jordan's East Ghor Main Canal (now known as the King Abdullah Canal ). Both projects were partially funded by the United States, after Israel and Jordan provided assurances they would abide by their allocations. In 1965, President Nasser assured the American undersecretary of state , Philip Talbot, that the Arabs would not exceed the water quotas prescribed by the Johnston plan. [ qt 1 ] At this point, the other Arab states resolved to reduce the operation of Israel's National Water Carrier by diverting the headwaters of the Jordan, leading to a series of military clashes which would help precipitate the 1967 Six-Day War . [ 9 ] [ 14 ] | https://en.wikipedia.org/wiki/Jordan_Valley_Unified_Water_Plan |
The Lagrangian in scalar-tensor theory can be expressed in the Jordan frame or in the Einstein frame , which are field variables that stress different aspects of the gravitational field equations and the evolution equations of the matter fields. In the Jordan frame the scalar field or some function of it multiplies the Ricci scalar in the Lagrangian and the matter is typically coupled minimally to the metric, whereas in the Einstein frame the Ricci scalar is not multiplied by the scalar field and the matter is coupled non-minimally. As a result, in the Einstein frame the field equations for the space-time metric resemble the Einstein equations but test particles do not move on geodesics of the metric. On the other hand, in the Jordan frame test particles move on geodesics, but the field equations are very different from Einstein equations. The causal structure in both frames is always equivalent and the frames can be transformed into each other as convenient for the given application.
Christopher Hill and Graham Ross have shown that there exist ``gravitational contact terms" in the Jordan frame, whereby the action is modified by graviton exchange. This modification leads back to the Einstein frame as the effective theory. [ 1 ] Contact interactions arise in Feynman diagrams when a vertex contains a power of the exchanged momentum, q 2 {\displaystyle q^{2}} , which then cancels against the Feynman propagator , 1 / q 2 {\displaystyle 1/q^{2}} , leading to a point-like interaction. This must be included as part of the effective action of the theory. When the contact term is included results for amplitudes in the Jordan frame will be equivalent to those in the Einstein frame, and
results of physical calculations in the Jordan frame that omit the contact terms will generally be incorrect. This implies that the Jordan frame action is misleading, and the Einstein frame is uniquely correct for fully representing the physics.
If we perform the Weyl rescaling g ~ μ ν = Φ − 2 / ( d − 2 ) g μ ν {\displaystyle {\tilde {g}}_{\mu \nu }=\Phi ^{-2/(d-2)}g_{\mu \nu }} , then the Riemann and Ricci tensors are modified as follows.
As an example consider the transformation of a simple Scalar-tensor action with an arbitrary set of matter fields ψ m {\displaystyle \psi _{\mathrm {m} }} coupled minimally to the curved background
The tilde fields then correspond to quantities in the Jordan frame and the fields without the tilde correspond to fields in the Einstein frame. See that the matter action S m {\displaystyle S_{\mathrm {m} }} changes only in the rescaling of the metric.
The Jordan and Einstein frames are constructed to render certain parts of physical equations simpler which also gives the frames and the fields appearing in them particular physical interpretations. For instance, in the Einstein frame, the equations for the gravitational field will be of the form
I.e., they can be interpreted as the usual Einstein equations with particular sources on the right-hand side. Similarly, in the Newtonian limit one would recover the Poisson equation for the Newtonian potential with separate source terms.
However, by transforming to the Einstein frame the matter fields are now coupled not only to the background but also to the field Φ {\displaystyle \Phi } which now acts as an effective potential. Specifically, an isolated test particle will experience a universal four-acceleration
where u μ {\displaystyle u^{\mu }} is the particle four-velocity. I.e., no particle will be in free-fall in the Einstein frame.
On the other hand, in the Jordan frame, all the matter fields ψ m {\displaystyle \psi _{\mathrm {m} }} are coupled minimally to g ~ μ ν {\displaystyle {\tilde {g}}_{\mu \nu }} and isolated test particles will move on geodesics with respect to the metric g ~ μ ν {\displaystyle {\tilde {g}}_{\mu \nu }} . This means that if we were to reconstruct the Riemann curvature tensor by measurements of geodesic deviation, we would in fact obtain the curvature tensor in the Jordan frame. When, on the other hand, we deduce on the presence of matter sources from gravitational lensing from the usual relativistic theory, we obtain the distribution of the matter sources in the sense of the Einstein frame.
Jordan frame gravity can be used to calculate type IV singular bouncing cosmological evolution, to derive the type IV singularity. [ 2 ]
This relativity -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jordan_and_Einstein_frames |
In topology , the Jordan curve theorem ( JCT ), formulated by Camille Jordan in 1887, asserts that every Jordan curve (a plane simple closed curve) divides the plane into an "interior" region bounded by the curve (not to be confused with the interior of a set) and an "exterior" region containing all of the nearby and far away exterior points. Every continuous path connecting a point of one region to a point of the other intersects with the curve somewhere.
While the theorem seems intuitively obvious, it takes some ingenuity to prove it by elementary means. "Although the JCT is one of the best known topological theorems, there are many, even among professional mathematicians, who have never read a proof of it." ( Tverberg (1980 , Introduction)). More transparent proofs rely on the mathematical machinery of algebraic topology , and these lead to generalizations to higher-dimensional spaces .
The Jordan curve theorem is named after the mathematician Camille Jordan (1838–1922), who published its first claimed proof in 1887. [ 1 ] [ 2 ] For decades, mathematicians generally thought that this proof was flawed and that the first rigorous proof was carried out by Oswald Veblen . However, this notion has been overturned by Thomas C. Hales and others. [ 3 ]
A Jordan curve or a simple closed curve in the plane R 2 {\displaystyle \mathbb {R} ^{2}} is the image C {\displaystyle C} of an injective continuous map of a circle into the plane, φ : S 1 → R 2 {\displaystyle \varphi :S^{1}\to \mathbb {R} ^{2}} . A Jordan arc in the plane is the image of an injective continuous map of a closed and bounded interval [ a , b ] {\displaystyle [a,b]} into the plane. It is a plane curve that is not necessarily smooth nor algebraic .
Alternatively, a Jordan curve is the image of a continuous map φ : [ 0 , 1 ] → R 2 {\displaystyle \varphi :[0,1]\to \mathbb {R} ^{2}} such that φ ( 0 ) = φ ( 1 ) {\displaystyle \varphi (0)=\varphi (1)} and the restriction of φ {\displaystyle \varphi } to [ 0 , 1 ) {\displaystyle [0,1)} is injective. The first two conditions say that C {\displaystyle C} is a continuous loop, whereas the last condition stipulates that C {\displaystyle C} has no self-intersection points.
With these definitions, the Jordan curve theorem can be stated as follows:
Theorem — Let C {\displaystyle C} be a Jordan curve in the plane R 2 {\displaystyle \mathbb {R} ^{2}} . Then its complement , R 2 ∖ C {\displaystyle \mathbb {R} ^{2}\setminus C} , consists of exactly two connected components . One of these components is bounded (the interior ) and the other is unbounded (the exterior ), and the curve C {\displaystyle C} is the boundary of each component.
In contrast, the complement of a Jordan arc in the plane is connected.
The Jordan curve theorem was independently generalized to higher dimensions by H. Lebesgue and L. E. J. Brouwer in 1911, resulting in the Jordan–Brouwer separation theorem .
Theorem — Let X be an n -dimensional topological sphere in the ( n +1)-dimensional Euclidean space R n +1 ( n > 0), i.e. the image of an injective continuous mapping of the n -sphere S n into R n +1 . Then the complement Y of X in R n +1 consists of exactly two connected components. One of these components is bounded (the interior) and the other is unbounded (the exterior). The set X is their common boundary.
The proof uses homology theory . It is first established that, more generally, if X is homeomorphic to the k -sphere, then the reduced integral homology groups of Y = R n +1 \ X are as follows:
This is proved by induction in k using the Mayer–Vietoris sequence . When n = k , the zeroth reduced homology of Y has rank 1, which means that Y has 2 connected components (which are, moreover, path connected ), and with a bit of extra work, one shows that their common boundary is X . A further generalization was found by J. W. Alexander , who established the Alexander duality between the reduced homology of a compact subset X of R n +1 and the reduced cohomology of its complement. If X is an n -dimensional compact connected submanifold of R n +1 (or S n +1 ) without boundary, its complement has 2 connected components.
There is a strengthening of the Jordan curve theorem, called the Jordan–Schönflies theorem , which states that the interior and the exterior planar regions determined by a Jordan curve in R 2 are homeomorphic to the interior and exterior of the unit disk . In particular, for any point P in the interior region and a point A on the Jordan curve, there exists a Jordan arc connecting P with A and, with the exception of the endpoint A , completely lying in the interior region. An alternative and equivalent formulation of the Jordan–Schönflies theorem asserts that any Jordan curve φ : S 1 → R 2 , where S 1 is viewed as the unit circle in the plane, can be extended to a homeomorphism ψ : R 2 → R 2 of the plane. Unlike Lebesgue's and Brouwer's generalization of the Jordan curve theorem, this statement becomes false in higher dimensions: while the exterior of the unit ball in R 3 is simply connected , because it retracts onto the unit sphere, the Alexander horned sphere is a subset of R 3 homeomorphic to a sphere , but so twisted in space that the unbounded component of its complement in R 3 is not simply connected, and hence not homeomorphic to the exterior of the unit ball.
The Jordan curve theorem can be proved from the Brouwer fixed point theorem (in 2 dimensions), [ 4 ] and the Brouwer fixed point theorem can be proved from the Hex theorem: "every game of Hex has at least one winner", from which we obtain a logical implication: Hex theorem implies Brouwer fixed point theorem, which implies Jordan curve theorem. [ 5 ]
It is clear that Jordan curve theorem implies the "strong Hex theorem": "every game of Hex ends with exactly one winner, with no possibility of both sides losing or both sides winning", thus the Jordan curve theorem is equivalent to the strong Hex theorem, which is a purely discrete theorem.
The Brouwer fixed point theorem, by being sandwiched between the two equivalent theorems, is also equivalent to both. [ 6 ]
In reverse mathematics, and computer-formalized mathematics, the Jordan curve theorem is commonly proved by first converting it to an equivalent discrete version similar to the strong Hex theorem, then proving the discrete version. [ 7 ]
In image processing , a binary picture is a discrete square grid of 0 and 1, or equivalently, a compact subset of Z 2 {\displaystyle \mathbb {Z} ^{2}} . Topological invariants on R 2 {\displaystyle \mathbb {R} ^{2}} , such as number of components, might fail to be well-defined for Z 2 {\displaystyle \mathbb {Z} ^{2}} if Z 2 {\displaystyle \mathbb {Z} ^{2}} does not have an appropriately defined graph structure .
There are two obvious graph structures on Z 2 {\displaystyle \mathbb {Z} ^{2}} :
Both graph structures fail to satisfy the strong Hex theorem. The 4-neighbor square grid allows a no-winner situation, and the 8-neighbor square grid allows a two-winner situation. Consequently, connectedness properties in R 2 {\displaystyle \mathbb {R} ^{2}} , such as the Jordan curve theorem, do not generalize to Z 2 {\displaystyle \mathbb {Z} ^{2}} under either graph structure.
If the "6-neighbor square grid" structure is imposed on Z 2 {\displaystyle \mathbb {Z} ^{2}} , then it is the hexagonal grid, and thus satisfies the strong Hex theorem, allowing the Jordan curve theorem to generalize. For this reason, when computing connected components in a binary image, the 6-neighbor square grid is generally used. [ 8 ]
The Steinhaus chessboard theorem in some sense shows that the 4-neighbor grid and the 8-neighbor grid "together" implies the Jordan curve theorem, and the 6-neighbor grid is a precise interpolation between them. [ 9 ] [ 10 ]
The theorem states that: suppose you put bombs on some squares on a n × n {\displaystyle n\times n} chessboard, so that a king cannot move from the bottom side to the top side without stepping on a bomb, then a rook can move from the left side to the right side stepping only on bombs.
The statement of the Jordan curve theorem may seem obvious at first, but it is a rather difficult theorem to prove. Bernard Bolzano was the first to formulate a precise conjecture, observing that it was not a self-evident statement, but that it required a proof. [ 11 ] It is easy to establish this result for polygons , but the problem came in generalizing it to all kinds of badly behaved curves, which include nowhere differentiable curves, such as the Koch snowflake and other fractal curves , or even a Jordan curve of positive area constructed by Osgood (1903) .
The first proof of this theorem was given by Camille Jordan in his lectures on real analysis , and was published in his book Cours d'analyse de l'École Polytechnique . [ 1 ] There is some controversy about whether Jordan's proof was complete: the majority of commenters on it have claimed that the first complete proof was given later by Oswald Veblen , who said the following about Jordan's proof:
His proof, however, is unsatisfactory to many mathematicians. It assumes the theorem without proof in the important special case of a simple polygon, and of the argument from that point on, one must admit at least that all details are not given. [ 12 ]
However, Thomas C. Hales wrote:
Nearly every modern citation that I have found agrees that the first correct proof is due to Veblen... In view of the heavy criticism of Jordan’s proof, I was surprised when I sat down to read his proof to find nothing objectionable about it. Since then, I have contacted a number of the authors who have criticized Jordan, and each case the author has admitted to having no direct knowledge of an error in Jordan’s proof. [ 13 ]
Hales also pointed out that the special case of simple polygons is not only an easy exercise, but was not really used by Jordan anyway, and quoted Michael Reeken as saying:
Jordan’s proof is essentially correct... Jordan’s proof does not present the details in a satisfactory way. But the idea is right, and with some polishing the proof would be impeccable. [ 14 ]
Earlier, Jordan's proof and another early proof by Charles Jean de la Vallée Poussin had already been critically analyzed and completed by Schoenflies (1924). [ 15 ]
Due to the importance of the Jordan curve theorem in low-dimensional topology and complex analysis , it received much attention from prominent mathematicians of the first half of the 20th century. Various proofs of the theorem and its generalizations were constructed by J. W. Alexander , Louis Antoine , Ludwig Bieberbach , Luitzen Brouwer , Arnaud Denjoy , Friedrich Hartogs , Béla Kerékjártó , Alfred Pringsheim , and Arthur Moritz Schoenflies .
New elementary proofs of the Jordan curve theorem, as well as simplifications of the earlier proofs, continue to be carried out.
The root of the difficulty is explained in Tverberg (1980) as follows. It is relatively simple to prove that the Jordan curve theorem holds for every Jordan polygon (Lemma 1), and every Jordan curve can be approximated arbitrarily well by a Jordan polygon (Lemma 2). A Jordan polygon is a polygonal chain , the boundary of a bounded connected open set , call it the open polygon, and its closure , the closed polygon. Consider the diameter δ {\displaystyle \delta } of the largest disk contained in the closed polygon. Evidently, δ {\displaystyle \delta } is positive. Using a sequence of Jordan polygons (that converge to the given Jordan curve) we have a sequence δ 1 , δ 2 , … {\displaystyle \delta _{1},\delta _{2},\dots } presumably converging to a positive number, the diameter δ {\displaystyle \delta } of the largest disk contained in the closed region bounded by the Jordan curve. However, we have to prove that the sequence δ 1 , δ 2 , … {\displaystyle \delta _{1},\delta _{2},\dots } does not converge to zero, using only the given Jordan curve, not the region presumably bounded by the curve. This is the point of Tverberg's Lemma 3. Roughly, the closed polygons should not thin to zero everywhere. Moreover, they should not thin to zero somewhere, which is the point of Tverberg's Lemma 4.
The first formal proof of the Jordan curve theorem was created by Hales (2007a) in the HOL Light system, in January 2005, and contained about 60,000 lines. Another rigorous 6,500-line formal proof was produced in 2005 by an international team of mathematicians using the Mizar system . Both the Mizar and the HOL Light proof rely on libraries of previously proved theorems, so these two sizes are not comparable. Nobuyuki Sakamoto and Keita Yokoyama ( 2007 ) showed that in reverse mathematics the Jordan curve theorem is equivalent to weak Kőnig's lemma over the system R C A 0 {\displaystyle {\mathsf {RCA}}_{0}} .
In computational geometry , the Jordan curve theorem can be used for testing whether a point lies inside or outside a simple polygon . [ 16 ] [ 17 ] [ 18 ]
From a given point, trace a ray that does not pass through any vertex of the polygon (all rays but a finite number are convenient). Then, compute the number n of intersections of the ray with an edge of the polygon. Jordan curve theorem proof implies that the point is inside the polygon if and only if n is odd .
Adler, Daskalakis and Demaine [ 19 ] prove that a computational version of Jordan's theorem is PPAD-complete . As a corollary, they show that Jordan's theorem implies the Brouwer fixed-point theorem . This complements the earlier result by Maehara, that Brouwer's fixed point theorem implies Jordan's theorem. [ 20 ] | https://en.wikipedia.org/wiki/Jordan_curve_theorem |
The Jordanian Engineers Association (in Arabic: نقابة المهندسين الأردنيين ) was established as a society for engineers in 1948, and was licensed in 1949. The first general assembly of the Engineering Professionals Association was established in 1958. Tawfiq Marar became the first Engineers' Association president. The Association has 11 branches in Jordan . There are two centers in Amman and Jerusalem . The first law of the Association was enacted in 1972. [ 1 ]
The Association has an independent legal personality run by a board elected by the general assembly in accordance with the provisions of the association law, and the association president represents it before the courts, administrative entities, and other departments. [ 2 ]
The Association makes an annual report stating its achievements and clarifying its financial position in financial reports . Every fund of the association also makes its respective annual report, and the administrative and financial reports are presented to the general assemblies for approval. [ 3 ]
As of 2017, the JEA had 143549 Registered Members, divided into six engineering chapters. Approximately 25% of its members are female, although this is expected to rise to 30% within the next 5 years. [ 4 ] | https://en.wikipedia.org/wiki/Jordanian_Engineers_Association |
Jordanus (the Jordan River ) was a constellation introduced in 1612 (or 1613) on a globe by Petrus Plancius and first shown in print by Jakob Bartsch in his book Usus Astronomicus Planisphaerii Stellati (1624).
One end lay in the present-day Canes Venatici and then it flowed through the areas now occupied by Leo Minor and Lynx , ending near Camelopardalis . [ 1 ] This constellation was not adopted in the atlases of Johann Bode and fell into disuse.
This constellation -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jordanus_(constellation) |
In mathematics , specifically linear algebra , the Jordan–Chevalley decomposition , named after Camille Jordan and Claude Chevalley , expresses a linear operator in a unique way as the sum of two other linear operators which are simpler to understand. Specifically, one part is potentially diagonalisable and the other is nilpotent . The two parts are polynomials in the operator, which makes them behave nicely in algebraic manipulations.
The decomposition has a short description when the Jordan normal form of the operator is given, but it exists under weaker hypotheses than are needed for the existence of a Jordan normal form. Hence the Jordan–Chevalley decomposition can be seen as a generalisation of the Jordan normal form, which is also reflected in several proofs of it.
It is closely related to the Wedderburn principal theorem about associative algebras , which also leads to several analogues in Lie algebras . Analogues of the Jordan–Chevalley decomposition also exist for elements of Linear algebraic groups and Lie groups via a multiplicative reformulation. The decomposition is an important tool in the study of all of these objects, and was developed for this purpose.
In many texts, the potentially diagonalisable part is also characterised as the semisimple part.
A basic question in linear algebra is whether an operator on a finite-dimensional vector space can be diagonalised . For example, this is closely related to the eigenvalues of the operator. In several contexts, one may be dealing with many operators which are not diagonalisable. Even over an algebraically closed field, a diagonalisation may not exist. In this context, the Jordan normal form achieves the best possible result akin to a diagonalisation. For linear operators over a field which is not algebraically closed , there may be no eigenvector at all. This latter point is not the main concern dealt with by the Jordan–Chevalley decomposition. To avoid this problem, instead potentially diagonalisable operators are considered, which are those that admit a diagonalisation over some field (or equivalently over the algebraic closure of the field under consideration).
The operators which are "the furthest away" from being diagonalisable are nilpotent operators . An operator (or more generally an element of a ring ) x {\displaystyle x} is said to be nilpotent when there is some positive integer m ≥ 1 {\displaystyle m\geq 1} such that x m = 0 {\displaystyle x^{m}=0} . In several contexts in abstract algebra , it is the case that the presence of nilpotent elements of a ring make them much more complicated to work with. [ citation needed ] To some extent, this is also the case for linear operators. The Jordan–Chevalley decomposition "separates out" the nilpotent part of an operator which causes it to be not potentially diagonalisable. So when it exists, the complications introduced by nilpotent operators and their interaction with other operators can be understood using the Jordan–Chevalley decomposition.
Historically, the Jordan–Chevalley decomposition was motivated by the applications to the theory of Lie algebras and linear algebraic groups , [ 1 ] as described in sections below .
Let K {\displaystyle K} be a field , V {\displaystyle V} a finite-dimensional vector space over K {\displaystyle K} , and T {\displaystyle T} a linear operator over V {\displaystyle V} (equivalently, a matrix with entries from K {\displaystyle K} ). If the minimal polynomial of T {\displaystyle T} splits over K {\displaystyle K} (for example if K {\displaystyle K} is algebraically closed), then T {\displaystyle T} has a Jordan normal form T = S J S − 1 {\displaystyle T=SJS^{-1}} . If D {\displaystyle D} is the diagonal of J {\displaystyle J} , let R = J − D {\displaystyle R=J-D} be the remaining part. Then T = S D S − 1 + S R S − 1 {\displaystyle T=SDS^{-1}+SRS^{-1}} is a decomposition where S D S − 1 {\displaystyle SDS^{-1}} is diagonalisable and S R S − 1 {\displaystyle SRS^{-1}} is nilpotent. This restatement of the normal form as an additive decomposition not only makes the numerical computation more stable [ citation needed ] , but can be generalised to cases where the minimal polynomial of T {\displaystyle T} does not split.
If the minimal polynomial of T {\displaystyle T} splits into distinct linear factors, then T {\displaystyle T} is diagonalisable. Therefore, if the minimal polynomial of T {\displaystyle T} is at least separable , then T {\displaystyle T} is potentially diagonalisable. The Jordan–Chevalley decomposition is concerned with the more general case where the minimal polynomial of T {\displaystyle T} is a product of separable polynomials.
Let x : V → V {\displaystyle x:V\to V} be any linear operator on the finite-dimensional vector space V {\displaystyle V} over the field K {\displaystyle K} . A Jordan–Chevalley decomposition of x {\displaystyle x} is an expression of it as a sum
where x s {\displaystyle x_{s}} is potentially diagonalisable, x n {\displaystyle x_{n}} is nilpotent, and x s x n = x n x s {\displaystyle x_{s}x_{n}=x_{n}x_{s}} .
Jordan-Chevalley decomposition — Let x : V → V {\displaystyle x:V\to V} be any operator on the finite-dimensional vector space V {\displaystyle V} over the field K {\displaystyle K} . Then x {\displaystyle x} admits a Jordan-Chevalley decomposition if and only if the minimal polynomial of x {\displaystyle x} is a product of separable polynomials. Moreover, in this case, there is a unique Jordan-Chevalley decomposition, and x s {\displaystyle x_{s}} (and hence also x n {\displaystyle x_{n}} ) can be written as a polynomial (with coefficients from K {\displaystyle K} ) in x {\displaystyle x} with zero constant coefficient.
Several proofs are discussed in ( Couty, Esterle & Zarouf 2011 ). Two arguments are also described below.
If K {\displaystyle K} is a perfect field , then every polynomial is a product of separable polynomials (since every polynomial is a product of its irreducible factors, and these are separable over a perfect field). So in this case, the Jordan–Chevalley decomposition always exists. Moreover, over a perfect field, a polynomial is separable if and only if it is square-free. Therefore an operator is potentially diagonalisable if and only if its minimal polynomial is square-free. In general (over any field), the minimal polynomial of a linear operator is square-free if and only if the operator is semisimple . [ 2 ] (In particular, the sum of two commuting semisimple operators is always semisimple over a perfect field. The same statement is not true over general fields.) The property of being semisimple is more relevant than being potentially diagonalisable in most contexts where the Jordan–Chevalley decomposition is applied, such as for Lie algebras. [ citation needed ] For these reasons, many texts restrict to the case of perfect fields.
That x s {\displaystyle x_{s}} and x n {\displaystyle x_{n}} are polynomials in x {\displaystyle x} implies in particular that they commute with any operator that commutes with x {\displaystyle x} . This observation underlies the uniqueness proof.
Let x = x s + x n {\displaystyle x=x_{s}+x_{n}} be a Jordan–Chevalley decomposition in which x s {\displaystyle x_{s}} and (hence also) x n {\displaystyle x_{n}} are polynomials in x {\displaystyle x} . Let x = x s ′ + x n ′ {\displaystyle x=x_{s}'+x_{n}'} be any Jordan–Chevalley decomposition. Then x s − x s ′ = x n ′ − x n {\displaystyle x_{s}-x_{s}'=x_{n}'-x_{n}} , and x s ′ , x n ′ {\displaystyle x_{s}',x_{n}'} both commute with x {\displaystyle x} , hence with x s , x n {\displaystyle x_{s},x_{n}} since these are polynomials in x {\displaystyle x} . The sum of commuting nilpotent operators is again nilpotent, and the sum of commuting potentially diagonalisable operators again potentially diagonalisable (because they are simultaneously diagonalizable over the algebraic closure of K {\displaystyle K} ). Since the only operator which is both potentially diagonalisable and nilpotent is the zero operator it follows that x s − x s ′ = 0 = x n − x n ′ {\displaystyle x_{s}-x_{s}'=0=x_{n}-x_{n}'} .
To show that the condition that x {\displaystyle x} have a minimal polynomial which is a product of separable polynomials is necessary, suppose that x = x s + x n {\displaystyle x=x_{s}+x_{n}} is some Jordan–Chevalley decomposition. Letting p {\displaystyle p} be the separable minimal polynomial of x s {\displaystyle x_{s}} , one can check using the binomial theorem that p ( x s + x n ) {\displaystyle p(x_{s}+x_{n})} can be written as x n y {\displaystyle x_{n}y} where y {\displaystyle y} is some polynomial in x s , x n {\displaystyle x_{s},x_{n}} . Moreover, for some ℓ ≥ 1 {\displaystyle \ell \geq 1} , x n ℓ = 0 {\displaystyle x_{n}^{\ell }=0} . Thus p ( x ) ℓ = x n ℓ y ℓ = 0 {\displaystyle p(x)^{\ell }=x_{n}^{\ell }y^{\ell }=0} and so the minimal polynomial of x {\displaystyle x} must divide p ℓ {\displaystyle p^{\ell }} . As p ℓ {\displaystyle p^{\ell }} is a product of separable polynomials (namely of copies of p {\displaystyle p} ), so is the minimal polynomial.
If the ground field is not perfect , then a Jordan–Chevalley decomposition may not exist, as it is possible that the minimal polynomial is not a product of separable polynomials. The simplest such example is the following. Let p {\displaystyle p} be a prime number, let k {\displaystyle k} be an imperfect field of characteristic p , {\displaystyle p,} (e. g. k = F p ( t ) {\displaystyle k=\mathbb {F} _{p}(t)} ) and choose a ∈ k {\displaystyle a\in k} that is not a p {\displaystyle p} th power. Let V = k [ X ] / ( X p − a ) 2 , {\displaystyle V=k[X]/\left(X^{p}-a\right)^{2},} let x = X ¯ {\displaystyle x={\overline {X}}} be the image in the quotient and let T {\displaystyle T} be the k {\displaystyle k} -linear operator given by multiplication by x {\displaystyle x} in V {\displaystyle V} . Note that the minimal polynomial is precisely ( X p − a ) 2 {\displaystyle \left(X^{p}-a\right)^{2}} , which is inseparable and a square. By the necessity of the condition for the Jordan–Chevalley decomposition (as shown in the last section), this operator does not have a Jordan–Chevalley decomposition. It can be instructive to see concretely why there is at least no decomposition into a square-free and a nilpotent part.
Note that T {\displaystyle T} has as its invariant k {\displaystyle k} -linear subspaces precisely the ideals of V {\displaystyle V} viewed as a ring, which correspond to the ideals of k [ X ] {\displaystyle k[X]} containing ( X p − a ) 2 {\displaystyle \left(X^{p}-a\right)^{2}} . Since X p − a {\displaystyle X^{p}-a} is irreducible in k [ X ] , {\displaystyle k[X],} ideals of V {\displaystyle V} are 0 , {\displaystyle 0,} V {\displaystyle V} and J = ( x p − a ) V . {\displaystyle J=\left(x^{p}-a\right)V.} Suppose T = S + N {\displaystyle T=S+N} for commuting k {\displaystyle k} -linear operators S {\displaystyle S} and N {\displaystyle N} that are respectively semisimple (just over k {\displaystyle k} , which is weaker than semisimplicity over an algebraic closure of k {\displaystyle k} and also weaker than being potentially diagonalisable) and nilpotent. Since S {\displaystyle S} and N {\displaystyle N} commute, they each commute with T = S + N {\displaystyle T=S+N} and hence each acts k [ x ] {\displaystyle k[x]} -linearly on V {\displaystyle V} . Therefore S {\displaystyle S} and N {\displaystyle N} are each given by multiplication by respective members of V {\displaystyle V} s = S ( 1 ) {\displaystyle s=S(1)} and n = N ( 1 ) , {\displaystyle n=N(1),} with s + n = T ( 1 ) = x {\displaystyle s+n=T(1)=x} . Since N {\displaystyle N} is nilpotent, n {\displaystyle n} is nilpotent in V , {\displaystyle V,} therefore n ¯ = 0 {\displaystyle {\overline {n}}=0} in V / J , {\displaystyle V/J,} for V / J {\displaystyle V/J} is a field. Hence, n ∈ J , {\displaystyle n\in J,} therefore n = ( x p − a ) h ( x ) {\displaystyle n=\left(x^{p}-a\right)h(x)} for some polynomial h ( X ) ∈ k [ X ] {\displaystyle h(X)\in k[X]} . Also, we see that n 2 = 0 {\displaystyle n^{2}=0} . Since k {\displaystyle k} is of characteristic p , {\displaystyle p,} we have x p = s p + n p = s p {\displaystyle x^{p}=s^{p}+n^{p}=s^{p}} . On the other hand, since x ¯ = s ¯ {\displaystyle {\overline {x}}={\overline {s}}} in A / J , {\displaystyle A/J,} we have h ( s ¯ ) = h ( x ¯ ) , {\displaystyle h\left({\overline {s}}\right)=h\left({\overline {x}}\right),} therefore h ( s ) − h ( x ) ∈ J {\displaystyle h(s)-h(x)\in J} in V . {\displaystyle V.} Since ( x p − a ) J = 0 , {\displaystyle \left(x^{p}-a\right)J=0,} we have ( x p − a ) h ( x ) = ( x p − a ) h ( s ) . {\displaystyle \left(x^{p}-a\right)h(x)=\left(x^{p}-a\right)h(s).} Combining these results we get x = s + n = s + ( s p − a ) h ( s ) . {\displaystyle x=s+n=s+\left(s^{p}-a\right)h(s).} This shows that s {\displaystyle s} generates V {\displaystyle V} as a k {\displaystyle k} -algebra and thus the S {\displaystyle S} -stable k {\displaystyle k} -linear subspaces of V {\displaystyle V} are ideals of V , {\displaystyle V,} i.e. they are 0 , {\displaystyle 0,} J {\displaystyle J} and V . {\displaystyle V.} We see that J {\displaystyle J} is an S {\displaystyle S} -invariant subspace of V {\displaystyle V} which has no complement S {\displaystyle S} -invariant subspace, contrary to the assumption that S {\displaystyle S} is semisimple. Thus, there is no decomposition of T {\displaystyle T} as a sum of commuting k {\displaystyle k} -linear operators that are respectively semisimple and nilpotent.
If instead of with the polynomial ( X p − a ) 2 {\displaystyle \left(X^{p}-a\right)^{2}} , the same construction is performed with X p − a {\displaystyle {X^{p}}-a} , the resulting operator T {\displaystyle T} still does not admit a Jordan–Chevalley decomposition by the main theorem. However, T {\displaystyle T} is semi-simple. The trivial decomposition T = T + 0 {\displaystyle T=T+0} hence expresses T {\displaystyle T} as a sum of a semisimple and a nilpotent operator, both of which are polynomials in T {\displaystyle T} .
This construction is similar to Hensel's lemma in that it uses an algebraic analogue of Taylor's theorem to find an element with a certain algebraic property via a variant of Newton's method . In this form, it is taken from ( Geck 2022 ).
Let x {\displaystyle x} have minimal polynomial p {\displaystyle p} and assume this is a product of separable polynomials. This condition is equivalent to demanding that there is some separable q {\displaystyle q} such that q ∣ p {\displaystyle q\mid p} and p ∣ q m {\displaystyle p\mid q^{m}} for some m ≥ 1 {\displaystyle m\geq 1} . By the Bézout lemma , there are polynomials u {\displaystyle u} and v {\displaystyle v} such that u q + v q ′ = 1 {\displaystyle {uq+{vq'}}=1} . This can be used to define a recursion x n + 1 = x n − v ( x n ) q ( x n ) {\displaystyle x_{n+1}=x_{n}-v(x_{n})q(x_{n})} , starting with x 0 = x {\displaystyle x_{0}=x} . Letting X {\displaystyle {\mathfrak {X}}} be the algebra of operators which are polynomials in x {\displaystyle x} , it can be checked by induction that for all n {\displaystyle n} :
Thus, as soon as 2 n ≥ m {\displaystyle 2^{n}\geq m} , q ( x n ) = 0 {\displaystyle q(x_{n})=0} by the second point since p ∣ q m {\displaystyle p\mid q^{m}} and p ( x ) = 0 {\displaystyle p(x)=0} , so the minimal polynomial of x n {\displaystyle x_{n}} will divide q {\displaystyle q} and hence be separable. Moreover, x n {\displaystyle x_{n}} will be a polynomial in x {\displaystyle x} by the first point and x n − x {\displaystyle x_{n}-x} will be nilpotent by the third point (in fact, ( x n − x ) m = 0 {\displaystyle (x_{n}-x)^{m}=0} ). Therefore, x = x n + ( x − x n ) {\displaystyle x=x_{n}+(x-x_{n})} is then the Jordan–Chevalley decomposition of x {\displaystyle x} . Q.E.D.
This proof, besides being completely elementary, has the advantage that it is algorithmic : By the Cayley–Hamilton theorem , p {\displaystyle p} can be taken to be the characteristic polynomial of x {\displaystyle x} , and in many contexts, q {\displaystyle q} can be determined from p {\displaystyle p} . [ 3 ] Then v {\displaystyle v} can be determined using the Euclidean algorithm . The iteration of applying the polynomial v q {\displaystyle vq} to the matrix then can be performed until either v ( x n ) q ( x n ) = 0 {\displaystyle v(x_{n})q(x_{n})=0} (because then all later values will be equal) or 2 n {\displaystyle 2^{n}} exceeds the dimension of the vector space on which x {\displaystyle x} is defined (where n {\displaystyle n} is the number of iteration steps performed, as above).
This proof, or variants of it, is commonly used to establish the Jordan–Chevalley decomposition. It has the advantage that it is very direct and describes quite precisely how close one can get to a Jordan–Chevalley decomposition: If L {\displaystyle L} is the splitting field of the minimal polynomial of x {\displaystyle x} and G {\displaystyle G} is the group of automorphisms of L {\displaystyle L} that fix the base field K {\displaystyle K} , then the set F {\displaystyle F} of elements of L {\displaystyle L} that are fixed by all elements of G {\displaystyle G} is a field with inclusions K ⊆ F ⊆ L {\displaystyle K\subseteq F\subseteq L} (see Galois correspondence ). Below it is argued that x {\displaystyle x} admits a Jordan–Chevalley decomposition over F {\displaystyle F} , but not any smaller field. [ citation needed ] This argument does not use Galois theory . However, Galois theory is required deduce from this the condition for the existence of the Jordan-Chevalley given above.
Above it was observed that if x {\displaystyle x} has a Jordan normal form (i. e. if the minimal polynomial of x {\displaystyle x} splits), then it has a Jordan Chevalley decomposition. In this case, one can also see directly that x n {\displaystyle x_{n}} (and hence also x s {\displaystyle x_{s}} ) is a polynomial in x {\displaystyle x} . Indeed, it suffices to check this for the decomposition of the Jordan matrix J = D + R {\displaystyle J=D+R} . This is a technical argument, but does not require any tricks beyond the Chinese remainder theorem .
In the Jordan normal form, we have written V = ⨁ i = 1 r V i {\displaystyle V=\bigoplus _{i=1}^{r}V_{i}} where r {\displaystyle r} is the number of Jordan blocks and x | V i {\displaystyle x|_{V_{i}}} is one Jordan block. Now let f ( t ) = det ( t I − x ) {\displaystyle f(t)=\operatorname {det} (tI-x)} be the characteristic polynomial of x {\displaystyle x} . Because f {\displaystyle f} splits, it can be written as f ( t ) = ∏ i = 1 r ( t − λ i ) d i {\displaystyle f(t)=\prod _{i=1}^{r}(t-\lambda _{i})^{d_{i}}} , where r {\displaystyle r} is the number of Jordan blocks, λ i {\displaystyle \lambda _{i}} are the distinct eigenvalues, and d i {\displaystyle d_{i}} are the sizes of the Jordan blocks, so d i = dim V i {\displaystyle d_{i}=\dim V_{i}} . Now, the Chinese remainder theorem applied to the polynomial ring k [ t ] {\displaystyle k[t]} gives a polynomial p ( t ) {\displaystyle p(t)} satisfying the conditions
(There is a redundancy in the conditions if some λ i {\displaystyle \lambda _{i}} is zero but that is not an issue; just remove it from the conditions.) The condition p ( t ) ≡ λ i mod ( t − λ i ) d i {\displaystyle p(t)\equiv \lambda _{i}{\bmod {(}}t-\lambda _{i})^{d_{i}}} , when spelled out, means that p ( t ) − λ i = g i ( t ) ( t − λ i ) d i {\displaystyle p(t)-\lambda _{i}=g_{i}(t)(t-\lambda _{i})^{d_{i}}} for some polynomial g i ( t ) {\displaystyle g_{i}(t)} . Since ( x − λ i I ) d i {\displaystyle (x-\lambda _{i}I)^{d_{i}}} is the zero map on V i {\displaystyle V_{i}} , p ( x ) {\displaystyle p(x)} and x s {\displaystyle x_{s}} agree on each V i {\displaystyle V_{i}} ; i.e., p ( x ) = x s {\displaystyle p(x)=x_{s}} . Also then q ( x ) = x n {\displaystyle q(x)=x_{n}} with q ( t ) = t − p ( t ) {\displaystyle q(t)=t-p(t)} . The condition p ( t ) ≡ 0 mod t {\displaystyle p(t)\equiv 0{\bmod {t}}} ensures that p ( t ) {\displaystyle p(t)} and q ( t ) {\displaystyle q(t)} have no constant terms. This completes the proof of the theorem in case the minimal polynomial of x {\displaystyle x} splits.
This fact can be used to deduce the Jordan–Chevalley decomposition in the general case. Let L {\displaystyle L} be the splitting field of the minimal polynomial of x {\displaystyle x} , so that x {\displaystyle x} does admit a Jordan normal form over L {\displaystyle L} . Then, by the argument just given, x {\displaystyle x} has a Jordan–Chevalley decomposition x = c ( x ) + ( x − c ( x ) ) {\displaystyle x={c(x)}+{(x-{c(x)})}} where c {\displaystyle c} is a polynomial with coefficients from L {\displaystyle L} , c ( x ) {\displaystyle c(x)} is diagonalisable (over L {\displaystyle L} ) and x − c ( x ) {\displaystyle x-c(x)} is nilpotent.
Let σ {\displaystyle \sigma } be a field automorphism of L {\displaystyle L} which fixes K {\displaystyle K} . Then c ( x ) + ( x − c ( x ) ) = x = σ ( x ) = σ ( c ( x ) ) + σ ( x − c ( x ) ) {\displaystyle c(x)+(x-{c(x)})=x={\sigma (x)}={\sigma ({c(x)})}+{\sigma (x-{c(x)})}} Here σ ( c ( x ) ) = σ ( c ) ( x ) {\displaystyle \sigma (c(x))=\sigma (c)(x)} is a polynomial in x {\displaystyle x} , so is x − c ( x ) {\displaystyle x-c(x)} . Thus, σ ( c ( x ) ) {\displaystyle \sigma (c(x))} and σ ( x − c ( x ) ) {\displaystyle \sigma (x-c(x))} commute. Also, σ ( c ( x ) ) {\displaystyle \sigma (c(x))} is potentially diagonalisable and σ ( x − c ( x ) ) {\displaystyle \sigma ({x-c(x)})} is nilpotent. Thus, by the uniqueness of the Jordan–Chevalley decomposition (over L {\displaystyle L} ), σ ( c ( x ) ) = c ( x ) {\displaystyle \sigma (c(x))=c(x)} and σ ( c ( x ) ) = c ( x ) {\displaystyle \sigma (c(x))=c(x)} . Therefore, by definition, x s , x n {\displaystyle x_{s},x_{n}} are endomorphisms (represented by matrices) over F {\displaystyle F} . Finally, since { 1 , x , x 2 , … } {\displaystyle \left\{1,x,x^{2},\dots \right\}} contains an L {\displaystyle L} -basis that spans the space containing x s , x n {\displaystyle x_{s},x_{n}} , by the same argument, we also see that c {\displaystyle c} has coefficients in F {\displaystyle F} . Q.E.D.
If the minimal polynomial of x {\displaystyle x} is a product of separable polynomials, then the field extension L / K {\displaystyle L/K} is Galois , meaning that F = K {\displaystyle F=K} .
The Jordan–Chevalley decomposition is very closely related to the Wedderburn principal theorem in the following formulation: [ 4 ]
Wedderburn principal theorem — Let A {\displaystyle A} be a finite-dimensional associative algebra over the field K {\displaystyle K} with Jacobson radical J {\displaystyle J} . Then A / J {\displaystyle A/J} is separable if and only if A {\displaystyle A} has a separable semisimple subalgebra B {\displaystyle B} such that A = B ⊕ J {\displaystyle A=B\oplus J} .
Usually, the term „separable“ in this theorem refers to the general concept of a separable algebra and the theorem might then be established as a corollary of a more general high-powered result. [ 5 ] However, if it is instead interpreted in the more basic sense that every element have a separable minimal polynomial, then this statement is essentially equivalent to the Jordan–Chevalley decomposition as described above. This gives a different way to view the decomposition, and for instance ( Jacobson 1979 ) takes this route for establishing it.
To see how the Jordan–Chevalley decomposition follows from the Wedderburn principal theorem, let V {\displaystyle V} be a finite-dimensional vector space over the field K {\displaystyle K} , x : V → V {\displaystyle x:V\to V} an endomorphism with a minimal polynomial which is a product of separable polynomials and A = K [ x ] ⊂ End ( V ) {\displaystyle A=K[x]\subset \operatorname {End} (V)} the subalgebra generated by x {\displaystyle x} . Note that A {\displaystyle A} is a commutative Artinian ring , so J {\displaystyle J} is also the nilradical of A {\displaystyle A} . Moreover, A / J {\displaystyle A/J} is separable, because if a ∈ A {\displaystyle a\in A} , then for minimal polynomial p {\displaystyle p} , there is a separable polynomial q {\displaystyle q} such that q ∣ p {\displaystyle q\mid p} and p ∣ q m {\displaystyle p\mid q^{m}} for some m ≥ 1 {\displaystyle m\geq 1} . Therefore q ( a ) ∈ J {\displaystyle q(a)\in J} , so the minimal polynomial of the image a + J ∈ A / J {\displaystyle a+J\in A/J} divides q {\displaystyle q} , meaning that it must be separable as well (since a divisor of a separable polynomial is separable). There is then the vector-space decomposition A = B ⊕ J {\displaystyle A=B\oplus J} with B {\displaystyle B} separable. In particular, the endomorphism x {\displaystyle x} can be written as x = x s + x n {\displaystyle x=x_{s}+x_{n}} where x s ∈ B {\displaystyle x_{s}\in B} and x n ∈ J {\displaystyle x_{n}\in J} . Moreover, both elements are, like any element of A {\displaystyle A} , polynomials in x {\displaystyle x} .
Conversely, the Wedderburn principal theorem in the formulation above is a consequence of the Jordan–Chevalley decomposition. If A {\displaystyle A} has a separable subalgebra B {\displaystyle B} such that A = B ⊕ J {\displaystyle A=B\oplus J} , then A / J ≅ B {\displaystyle A/J\cong B} is separable. Conversely, if A / J {\displaystyle A/J} is separable, then any element of A {\displaystyle A} is a sum of a separable and a nilpotent element. As shown above in #Proof of uniqueness and necessity , this implies that the minimal polynomial will be a product of separable polynomials. Let x ∈ A {\displaystyle x\in A} be arbitrary, define the operator T x : A → A , a ↦ a x {\displaystyle T_{x}:A\to A,a\mapsto ax} , and note that this has the same minimal polynomial as x {\displaystyle x} . So it admits a Jordan–Chevalley decomposition, where both operators are polynomials in T x {\displaystyle T_{x}} , hence of the form T s , T n {\displaystyle T_{s},T_{n}} for some s , n ∈ A {\displaystyle s,n\in A} which have separable and nilpotent minimal polynomials, respectively. Moreover, this decomposition is unique. Thus if B {\displaystyle B} is the subalgebra of all separable elements (that this is a subalgebra can be seen by recalling that s {\displaystyle s} is separable if and only if T s {\displaystyle T_{s}} is potentially diagonalisable), A = B ⊕ J {\displaystyle A=B\oplus J} (because J {\displaystyle J} is the ideal of nilpotent elements). The algebra B ≅ A / J {\displaystyle B\cong A/J} is separable and semisimple by assumption.
Over perfect fields, this result simplifies. Indeed, A / J {\displaystyle A/J} is then always separable in the sense of minimal polynomials: If a ∈ A {\displaystyle a\in A} , then the minimal polynomial p {\displaystyle p} is a product of separable polynomials, so there is a separable polynomial q {\displaystyle q} such that q ∣ p {\displaystyle q\mid p} and p ∣ q m {\displaystyle p\mid q^{m}} for some m ≥ 1 {\displaystyle m\geq 1} . Thus q ( a ) ∈ J {\displaystyle q(a)\in J} . So in A / J {\displaystyle A/J} , the minimal polynomial of a + J {\displaystyle a+J} divides q {\displaystyle q} and is hence separable. The crucial point in the theorem is then not that A / J {\displaystyle A/J} is separable (because that condition is vacuous), but that it is semisimple, meaning its radical is trivial.
The same statement is true for Lie algebras, but only in characteristic zero. This is the content of Levi’s theorem . (Note that the notions of semisimple in both results do indeed correspond, because in both cases this is equivalent to being the sum of simple subalgebras or having trivial radical, at least in the finite-dimensional case.)
The crucial point in the proof for the Wedderburn principal theorem above is that an element x ∈ A {\displaystyle x\in A} corresponds to a linear operator T x : A → A {\displaystyle T_{x}:A\to A} with the same properties. In the theory of Lie algebras, this corresponds to the adjoint representation of a Lie algebra g {\displaystyle {\mathfrak {g}}} . This decomposed operator has a Jordan–Chevalley decomposition ad ( x ) = ad ( x ) s + ad ( x ) n {\displaystyle \operatorname {ad} (x)=\operatorname {ad} (x)_{s}+\operatorname {ad} (x)_{n}} . Just as in the associative case, this corresponds to a decomposition of x {\displaystyle x} , but polynomials are not available as a tool. One context in which this does makes sense is the restricted case where g {\displaystyle {\mathfrak {g}}} is contained in the Lie algebra g l ( V ) {\displaystyle {\mathfrak {gl}}(V)} of the endomorphisms of a finite-dimensional vector space V {\displaystyle V} over the perfect field K {\displaystyle K} . Indeed, any semisimple Lie algebra can be realised in this way. [ 6 ]
If x = x s + x n {\displaystyle x=x_{s}+x_{n}} is the Jordan decomposition, then ad ( x ) = ad ( x s ) + ad ( x n ) {\displaystyle \operatorname {ad} (x)=\operatorname {ad} (x_{s})+\operatorname {ad} (x_{n})} is the Jordan decomposition of the adjoint endomorphism ad ( x ) {\displaystyle \operatorname {ad} (x)} on the vector space g {\displaystyle {\mathfrak {g}}} . Indeed, first, ad ( x s ) {\displaystyle \operatorname {ad} (x_{s})} and ad ( x n ) {\displaystyle \operatorname {ad} (x_{n})} commute since [ ad ( x s ) , ad ( x n ) ] = ad ( [ x s , x n ] ) = 0 {\displaystyle [\operatorname {ad} (x_{s}),\operatorname {ad} (x_{n})]=\operatorname {ad} ([x_{s},x_{n}])=0} . Second, in general, for each endomorphism y ∈ g {\displaystyle y\in {\mathfrak {g}}} , we have:
Hence, by uniqueness, ad ( x ) s = ad ( x s ) {\displaystyle \operatorname {ad} (x)_{s}=\operatorname {ad} (x_{s})} and ad ( x ) n = ad ( x n ) {\displaystyle \operatorname {ad} (x)_{n}=\operatorname {ad} (x_{n})} .
The adjoint representation is a very natural and general representation of any Lie algebra. The argument above illustrates (and indeed proves) a general principle which generalises this: If π : g → g l ( V ) {\displaystyle \pi :{\mathfrak {g}}\to {\mathfrak {gl}}(V)} is any finite-dimensional representation of a semisimple finite-dimensional Lie algebra over a perfect field, then π {\displaystyle \pi } preserves the Jordan decomposition in the following sense: if x = x s + x n {\displaystyle x=x_{s}+x_{n}} , then π ( x s ) = π ( x ) s {\displaystyle \pi (x_{s})=\pi (x)_{s}} and π ( x n ) = π ( x ) n {\displaystyle \pi (x_{n})=\pi (x)_{n}} . [ 8 ] [ 9 ]
The Jordan decomposition can be used to characterize nilpotency of an endomorphism. Let k be an algebraically closed field of characteristic zero, E = End Q ( k ) {\displaystyle E=\operatorname {End} _{\mathbb {Q} }(k)} the endomorphism ring of k over rational numbers and V a finite-dimensional vector space over k . Given an endomorphism x : V → V {\displaystyle x:V\to V} , let x = s + n {\displaystyle x=s+n} be the Jordan decomposition. Then s {\displaystyle s} is diagonalizable; i.e., V = ⨁ V i {\textstyle V=\bigoplus V_{i}} where each V i {\displaystyle V_{i}} is the eigenspace for eigenvalue λ i {\displaystyle \lambda _{i}} with multiplicity m i {\displaystyle m_{i}} . Then for any φ ∈ E {\displaystyle \varphi \in E} let φ ( s ) : V → V {\displaystyle \varphi (s):V\to V} be the endomorphism such that φ ( s ) : V i → V i {\displaystyle \varphi (s):V_{i}\to V_{i}} is the multiplication by φ ( λ i ) {\displaystyle \varphi (\lambda _{i})} . Chevalley calls φ ( s ) {\displaystyle \varphi (s)} the replica of s {\displaystyle s} given by φ {\displaystyle \varphi } . (For example, if k = C {\displaystyle k=\mathbb {C} } , then the complex conjugate of an endomorphism is an example of a replica.) Now,
Nilpotency criterion — [ 10 ] x {\displaystyle x} is nilpotent (i.e., s = 0 {\displaystyle s=0} ) if and only if tr ( x φ ( s ) ) = 0 {\displaystyle \operatorname {tr} (x\varphi (s))=0} for every φ ∈ E {\displaystyle \varphi \in E} . Also, if k = C {\displaystyle k=\mathbb {C} } , then it suffices the condition holds for φ = {\displaystyle \varphi =} complex conjugation.
Proof: First, since n φ ( s ) {\displaystyle n\varphi (s)} is nilpotent,
If φ {\displaystyle \varphi } is the complex conjugation, this implies λ i = 0 {\displaystyle \lambda _{i}=0} for every i . Otherwise, take φ {\displaystyle \varphi } to be a Q {\displaystyle \mathbb {Q} } -linear functional φ : k → Q {\displaystyle \varphi :k\to \mathbb {Q} } followed by Q ↪ k {\displaystyle \mathbb {Q} \hookrightarrow k} . Applying that to the above equation, one gets:
and, since φ ( λ i ) {\displaystyle \varphi (\lambda _{i})} are all real numbers, φ ( λ i ) = 0 {\displaystyle \varphi (\lambda _{i})=0} for every i . Varying the linear functionals then implies λ i = 0 {\displaystyle \lambda _{i}=0} for every i . ◻ {\displaystyle \square }
A typical application of the above criterion is the proof of Cartan's criterion for solvability of a Lie algebra. It says: if g ⊂ g l ( V ) {\displaystyle {\mathfrak {g}}\subset {\mathfrak {gl}}(V)} is a Lie subalgebra over a field k of characteristic zero such that tr ( x y ) = 0 {\displaystyle \operatorname {tr} (xy)=0} for each x ∈ g , y ∈ D g = [ g , g ] {\displaystyle x\in {\mathfrak {g}},y\in D{\mathfrak {g}}=[{\mathfrak {g}},{\mathfrak {g}}]} , then g {\displaystyle {\mathfrak {g}}} is solvable.
Proof: [ 11 ] Without loss of generality, assume k is algebraically closed. By Lie's theorem and Engel's theorem , it suffices to show for each x ∈ D g {\displaystyle x\in D{\mathfrak {g}}} , x {\displaystyle x} is a nilpotent endomorphism of V . Write x = ∑ i [ x i , y i ] {\textstyle x=\sum _{i}[x_{i},y_{i}]} . Then we need to show:
is zero. Let g ′ = g l ( V ) {\displaystyle {\mathfrak {g}}'={\mathfrak {gl}}(V)} . Note we have: ad g ′ ( x ) : g → D g {\displaystyle \operatorname {ad} _{{\mathfrak {g}}'}(x):{\mathfrak {g}}\to D{\mathfrak {g}}} and, since ad g ′ ( s ) {\displaystyle \operatorname {ad} _{{\mathfrak {g}}'}(s)} is the semisimple part of the Jordan decomposition of ad g ′ ( x ) {\displaystyle \operatorname {ad} _{{\mathfrak {g}}'}(x)} , it follows that ad g ′ ( s ) {\displaystyle \operatorname {ad} _{{\mathfrak {g}}'}(s)} is a polynomial without constant term in ad g ′ ( x ) {\displaystyle \operatorname {ad} _{{\mathfrak {g}}'}(x)} ; hence, ad g ′ ( s ) : g → D g {\displaystyle \operatorname {ad} _{{\mathfrak {g}}'}(s):{\mathfrak {g}}\to D{\mathfrak {g}}} and the same is true with φ ( s ) {\displaystyle \varphi (s)} in place of s {\displaystyle s} . That is, [ φ ( s ) , g ] ⊂ D g {\displaystyle [\varphi (s),{\mathfrak {g}}]\subset D{\mathfrak {g}}} , which implies the claim given the assumption. ◻ {\displaystyle \square }
In the formulation of Chevalley and Mostow , the additive decomposition states that an element X in a real semisimple Lie algebra g with Iwasawa decomposition g = k ⊕ a ⊕ n can be written as the sum of three commuting elements of the Lie algebra X = S + D + N , with S , D and N conjugate to elements in k , a and n respectively. In general the terms in the Iwasawa decomposition do not commute.
If x {\displaystyle x} is an invertible linear operator, it may be more convenient to use a multiplicative Jordan–Chevalley decomposition. This expresses x {\displaystyle x} as a product
where x s {\displaystyle x_{s}} is potentially diagonalisable, and x u − 1 {\displaystyle x_{u}-1} is nilpotent (one also says that x u {\displaystyle x_{u}} is unipotent).
The multiplicative version of the decomposition follows from the additive one since, as x s {\displaystyle x_{s}} is invertible (because the sum of an invertible operator and a nilpotent operator is invertible)
and 1 + x s − 1 x n {\displaystyle 1+x_{s}^{-1}x_{n}} is unipotent. (Conversely, by the same type of argument, one can deduce the additive version from the multiplicative one.)
The multiplicative version is closely related to decompositions encountered in a linear algebraic group. For this it is again useful to assume that the underlying field K {\displaystyle K} is perfect because then the Jordan–Chevalley decomposition exists for all matrices.
Let G {\displaystyle G} be a linear algebraic group over a perfect field. Then, essentially by definition, there is a closed embedding G ↪ G L n {\displaystyle G\hookrightarrow \mathbf {GL} _{n}} . Now, to each element g ∈ G {\displaystyle g\in G} , by the multiplicative Jordan decomposition, there are a pair of a semisimple element g s {\displaystyle g_{s}} and a unipotent element g u {\displaystyle g_{u}} a priori in G L n {\displaystyle \mathbf {GL} _{n}} such that g = g s g u = g u g s {\displaystyle g=g_{s}g_{u}=g_{u}g_{s}} . But, as it turns out, [ 12 ] the elements g s , g u {\displaystyle g_{s},g_{u}} can be shown to be in G {\displaystyle G} (i.e., they satisfy the defining equations of G ) and that they are independent of the embedding into G L n {\displaystyle \mathbf {GL} _{n}} ; i.e., the decomposition is intrinsic.
When G is abelian, G {\displaystyle G} is then the direct product of the closed subgroup of the semisimple elements in G and that of unipotent elements. [ 13 ]
The multiplicative decomposition states that if g is an element of the corresponding connected semisimple Lie group G with corresponding Iwasawa decomposition G = KAN , then g can be written as the product of three commuting elements g = sdu with s , d and u conjugate to elements of K , A and N respectively. In general the terms in the Iwasawa decomposition g = kan do not commute. | https://en.wikipedia.org/wiki/Jordan–Chevalley_decomposition |
In mathematics , the Jordan–Pólya numbers are the numbers that can be obtained by multiplying together one or more factorials , not required to be distinct from each other. For instance, 480 {\displaystyle 480} is a Jordan–Pólya number because 480 = 2 ! ⋅ 2 ! ⋅ 5 ! {\displaystyle 480=2!\cdot 2!\cdot 5!} . Every tree has a number of symmetries that is a Jordan–Pólya number, and every Jordan–Pólya number arises in this way as the order of an automorphism group of a tree. These numbers are named after Camille Jordan and George Pólya , who both wrote about them in the context of symmetries of trees. [ 1 ] [ 2 ]
These numbers grow more quickly than polynomials but more slowly than exponentials . As well as in the symmetries of trees, they arise as the numbers of transitive orientations of comparability graphs [ 3 ] and in the problem of finding factorials that can be represented as products of smaller factorials.
The sequence of Jordan–Pólya numbers begins: [ 4 ]
They form the smallest multiplicatively closed set containing all of the factorials.
The n {\displaystyle n} th Jordan–Pólya number grows more quickly than any polynomial of n {\displaystyle n} , but more slowly than any exponential function of n {\displaystyle n} . More precisely, for every ε > 0 {\displaystyle \varepsilon >0} , and every sufficiently large x {\displaystyle x} (depending on ε {\displaystyle \varepsilon } ), the number J ( x ) {\displaystyle J(x)} of Jordan–Pólya numbers up to x {\displaystyle x} obeys the inequalities [ 5 ] exp ( 2 − ε ) log x log log x < J ( x ) < exp ( 4 + ε ) log x log log log x log log x . {\displaystyle \exp {\frac {(2-\varepsilon ){\sqrt {\log x}}}{\log \log x}}<J(x)<\exp {\frac {(4+\varepsilon ){\sqrt {\log x}}\log \log \log x}{\log \log x}}.}
Every Jordan–Pólya number n {\displaystyle n} , except 2, has the property that its factorial n ! {\displaystyle n!} can be written as a product of smaller factorials. This can be done simply by expanding n ! = n ⋅ ( n − 1 ) ! {\displaystyle n!=n\cdot (n-1)!} and then replacing n {\displaystyle n} in this product by its representation as a product of factorials. It is conjectured , but unproven , that the only numbers n {\displaystyle n} whose factorial n ! {\displaystyle n!} equals a product of smaller factorials are the Jordan–Pólya numbers (except 2) and the two exceptional numbers 9 and 10, for which 9 ! = 2 ! ⋅ 3 ! ⋅ 3 ! ⋅ 7 ! {\displaystyle 9!=2!\cdot 3!\cdot 3!\cdot 7!} and 10 ! = 6 ! ⋅ 7 ! = 3 ! ⋅ 5 ! ⋅ 7 ! {\displaystyle 10!=6!\cdot 7!=3!\cdot 5!\cdot 7!} . The only other known representation of a factorial as a product of smaller factorials, not obtained by replacing n {\displaystyle n} in the product expansion of n ! {\displaystyle n!} , is 16 ! = 2 ! ⋅ 5 ! ⋅ 14 ! {\displaystyle 16!=2!\cdot 5!\cdot 14!} , but as 16 {\displaystyle 16} is itself a Jordan–Pólya number, it also has the representation 16 ! = 2 ! 4 ⋅ 15 ! {\displaystyle 16!=2!^{4}\cdot 15!} . [ 4 ] [ 6 ] | https://en.wikipedia.org/wiki/Jordan–Pólya_number |
The Jordan–Wigner transformation is a transformation that maps spin operators onto fermionic creation and annihilation operators . It was proposed by Pascual Jordan and Eugene Wigner [ 1 ] for one-dimensional lattice models , but now two-dimensional analogues of the transformation have also been created. The Jordan–Wigner transformation is often used to exactly solve 1D spin-chains such as the Ising and XY models by transforming the spin operators to fermionic operators and then diagonalizing in the fermionic basis.
This transformation actually shows that the distinction between spin-1/2 particles and fermions is nonexistent. It can be applied to systems with an arbitrary dimension.
In what follows we will show how to map a 1D spin chain of spin-1/2 particles to fermions.
Take spin-1/2 Pauli operators acting on a site j {\displaystyle j} of a 1D chain, σ j + , σ j − , σ j z {\displaystyle \sigma _{j}^{+},\sigma _{j}^{-},\sigma _{j}^{z}} . Taking the anticommutator of σ j + {\displaystyle \sigma _{j}^{+}} and σ j − {\displaystyle \sigma _{j}^{-}} , we find { σ j + , σ j − } = I {\displaystyle \{\sigma _{j}^{+},\sigma _{j}^{-}\}=I} , as would be expected from fermionic creation and annihilation operators. We might then be tempted to set
Now, we have the correct same-site fermionic relations { f j † , f j } = I {\displaystyle \{f_{j}^{\dagger },f_{j}\}=I} ; however, on different sites, we have the relation { f j † , f k } = 0 {\displaystyle \{f_{j}^{\dagger },f_{k}\}=0} , and [ σ j + , σ k − ] = 0 {\displaystyle [\sigma _{j}^{+},\sigma _{k}^{-}]=0} where j ≠ k {\displaystyle j\neq k} , so spins on different sites commute unlike fermions which anti-commute. We must remedy this before we can take the analogy very seriously.
A transformation which recovers the true fermion commutation relations from spin-operators was performed in 1928 by Jordan and Wigner. This is a special example of a Klein transformation . We take a chain of fermions, and define a new set of operators
They differ from the above only by a phase e ± i π ∑ k = 1 j − 1 f k † f k {\displaystyle e^{\pm i\pi \sum _{k=1}^{j-1}f_{k}^{\dagger }f_{k}}} . The phase is determined by the number of occupied fermionic modes in modes k = 1 , … , j − 1 {\displaystyle k=1,\ldots ,j-1} of the field. The phase is equal to + 1 {\displaystyle +1} if the number of occupied modes is even, and − 1 {\displaystyle -1} if the number of occupied modes is odd. This phase is often expressed as
The transformed spin operators now have the appropriate fermionic canonical anti-commutation relations
The above anti-commutation relations can be proved by invoking the relations
{ e ( − i π f j † f j ) , f j } = { e ( i π f j † f j ) , f j † } = 0 {\displaystyle \{e^{(-i\pi f_{j}^{\dagger }f_{j})},f_{j}\}=\{e^{(i\pi f_{j}^{\dagger }f_{j})},f_{j}^{\dagger }\}=0}
The inverse transformation is given by
Note that the definition of the fermionic operators is nonlocal with respect to the bosonic operators because we have to deal with an entire chain of operators to the left of the site the fermionic operators are defined with respect to. This is also true the other way around. This is an example of a 't Hooft loop , which is a disorder operator instead of an order operator . This is also an example of an S-duality .
If the system has more than one dimension the transformation can still be applied. It is only necessary to label the sites in an arbitrary way by a single index.
The Jordan–Wigner transformation can be inverted to map a fermionic Hamiltonian into a spin Hamiltonian. A series of spins is equivalent to a chain of qubits for quantum computing . Some molecular potentials can be efficiently simulated by a quantum computer using this transformation. [ 2 ] | https://en.wikipedia.org/wiki/Jordan–Wigner_transformation |
Jordi Folch Pi (March 25, 1911 – October 3, 1979) was a Spanish biochemist at Harvard University ( McLean Hospital ) who was recognized universally as one of the founders of the field of structural chemistry of complex lipids and as a leader in the development of neurochemistry as a distinct discipline within the neurosciences . [ 1 ] [ 2 ]
Folch was born in Barcelona, Spain . His father, Rafel Folch, was a lawyer and a Catalan poet, and his mother, Maria Pi, a teacher. Folch went to high school at the Lycée Français of Barcelona, from which he graduated in 1927. He went on to study medicine, receiving an M.D. degree from the University of Barcelona Medical school in 1932. [ 3 ]
Folch's clinical training at university included a period as an intern in the surgical clinic of Dr. Antoni Trias and as the sole physician in Almedret, a small Catalan village of 800 people. [ 3 ] Folch had the opportunity to study at the Institute of Physiology in Barcelona , an institute dedicated to carrying out basic research using contemporary methods and ideas and was founded by Jesus Maria Bellido and Folch's uncle August Pi Sunyer. [ 4 ] He worked as an assistant to his cousin Cesar Pi Sunyer and by the time he received his M.D. degree , they had jointly published four papers on glycogen synthesis in three different languages (German, French, and Spanish). Folch also studied blood glucose and lactic acid metabolism under the direction of the man he considered his scientific mentor, Professor Rosend Carrasco Formiguera. Folch's experiences at the Institute of Physiology intensified his interest in physiology and in clinical questions, particularly as they related to metabolic problems. Thanks to Carrasco's contacts, Francisco Duran Reynals, a biochemist at the Rockefeller Institute in New York, became interested in Folch and arranged for him to come to that institution as a volunteer. [ 3 ] [ 5 ]
In 1936, just before the Spanish Civil War broke out, he was accepted as a research fellow at the Rockefeller Institute in New York, and he took the post. At the insistence of his family (who had fought for the defeated Republican side—his brother Albert and sister Nuria had to exile into Mexico and his other brother Frederic spent a few months in prison after returning from exile in France), he decided to stay in the United States after the Civil War ended. [ 3 ]
Folch arrived at the Rockefeller in 1936 as a volunteer assistant. The following year he obtained a formal position as an assistant and later as an associate on the scientific staff of the Hospital of the Rockefeller Institute for Medical Research in Donald Van Slyke ’s department. Folch’s first assignment at the Rockefeller Institute was a project with Dr. Irvine Page on pituitary hormone disturbances. Folch's role was to analyze plasma lipids in these disorders. [ 6 ] He soon realized that the commonly used extraction of lipids with petroleum ether had problems in that the extraction was not quantitative and the extract contained non-lipid contaminants. He then devised a procedure that involved precipitation of lipids and proteins with colloidal iron and removal of most of the non-lipid components with water, which solved the contamination problem. [ 7 ]
During these first investigations he co-signed a paper with Donald Van Slyke on an improved manometric method for carbon analysis. Using this newly developed method, he characterized the isolated " cephalin " fraction from brain tissue that after Johannes Thudichum (the nineteenth-century founder of the field of structural neurochemistry) was considered as pure phosphatidyl ethanolamine . [ 6 ] Folch showed that the amount of carbon and of amines were not consistent with Thudichum's formula. This research led to Folch's first publication on brain lipids in 1941 and was followed over a period of several years by a series of famous papers showing that cephalin was not a single lipid but rather a mixture of three lipids (phosphatidyl ethanolamine, phosphatidyl serine , and inositol ). [ 7 ] Folch was the first to have elucidated the structure of phosphatidyl serine. Furthermore, he isolated subsequently mono-, di- and triphosphoinositides.
In 1944, Folch was appointed director of the new Biological Research Laboratory at the McLean Hospital (a division of Massachusetts General Hospital ) and assistant professor of biological chemistry at Harvard Medical School to develop a program in Neuroscience . His fundamental philosophy was that, to understand the structural chemistry of the brain, it was necessary to identify all brain components. [ 3 ] In 1947 he was joined by Marjorie Lees , together [ 8 ] they developed mild procedures for quantitative extraction of brain lipids leading to the classic method using a chloroform-methanol mixture and a phase partition with water which resulted in quantitative extraction of tissue lipids and removal of water-soluble contaminants. This method became one of the most highly cited papers of the 1950s and in 2014 was featured no. 9 in a list of the most highly cited papers in the history of Science. [ 9 ] The technique he developed for purifying the brain lipids is still referred to as " Folching " and is one of the most cited papers in the history of biochemistry. [ 3 ] Folch solution is a solution containing chloroform and methanol, usually in a 2:1 (vol/vol) ratio. [ 10 ] One of its uses is in separating polar from nonpolar compounds , for example separating nonpolar lipids from polar proteins and carbohydrates in blood serum. More modernly, citations have diminished likely due to the incorporation of the technique into the common English vocabulary as the verb "To Folch" to describe Folch's technique for extracting tissue. [ 10 ]
Folch successfully used his method to examine changes in brain lipids and proteins during development or diseases. [ 3 ] Together with Lees [ 8 ] they used their method to discover myelin proteolipid (defined as a new type of lipoprotein) in white matter and water-soluble glycolipids (named strandin at that time but now recognized as gangliosides ) in gray matter . Until the end of his career, the characterization of proteolipids was a major focus of Folch's work and interest. The Folch's isolation procedure provided the basis for later studies of acylated proteins and gangliosides.
Folch is considered to be one of the founders of the chemistry of complex lipids and correlatively as well as a leader in the development of neurochemistry. [ 3 ] He was one of the founders of the American Society for Neurochemistry and of the International Society for Neurochemistry . [ 3 ] In 1956, Folch became the first Professor of Neurochemistry at Harvard Academy of Arts and Sciences. In 1978, he was elected to the United States National Academy of Sciences . [ 3 ] He was also honorary professor in the Faculty of Medicine at the University of Barcelona, and was awarded honorary degrees by the University of Montpellier, France, and by the University of Chile, Santiago. After his retirement in 1977, he was Professor of Neurochemistry Emeritus and continued to be active as honorary biochemist at McLean Hospital until his death. [ 3 ]
His last name is often seen hyphenated ("Folch-Pi"). In the Spanish tradition of providing two identifiers, he often signed with both his paternal and his maternal last names. When he moved to America and married, he decided to hyphenate his paternal and maternal last names, so that his children would bear his full family heritage: "Folch-Pi". His last names are often mispronounced "Foltsch Pie" or "Folk Pie" but the correct Catalan pronunciation is "Folk Pea".
In 1945, Folch married Willa Babcock, a manuscript curator at the Francis Countway Medical Library, and would later become the academic dean of Tufts University . [ 11 ] The couple had three children. Folch died in Boston, Massachusetts on October 3, 1979, at 68 years of age.
This article about an American scientist is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jordi_Folch_Pi |
Jorge Eduardo Allende Rivera , (born 11 November 1934) is a Chilean biochemist and biophysicist known for his contributions to the understanding of proteic biosynthesis and how transfer RNA is generated, [ 1 ] and the regulation of maturation of amphibian eggs . He has been a foreign associate of the United States National Academy of Sciences since 2001, [ 2 ] and was awarded the Chilean National Prize for Nature Sciences (Chile) in 1992.
Jorge Allende was born in Cartago, Costa Rica, son of Octavio Allende Echeverría, Chilean Consul in the city of Puntarenas , and Amparo Rivera Ortiz, a Costa Rican artist. [ 3 ] Because of his father's job as a diplomat, he spent his childhood years between Costa Rica, Chile and the United States. He finished high school in a Jesuit School in New Orleans , Louisiana , where his father was appointed as the Chilean Consul. [ 4 ] Subsequently, he studied at Louisiana State University in Baton Rouge , Louisiana. He obtained the Bachelor of Science in chemistry degree in 1957.
He carried out his doctoral studies at Yale University in New Haven, Connecticut , United States, obtaining his Ph.D. in 1961 under the tutorship of Prof. F.M. Richards. He did post doctoral work with Prof. Fritz Lipmann at Rockefeller University and with Marshall Warren Nirenberg at NIH . [ 5 ]
During the 1960s, his research was focused on protein synthesis , a field in which he made crucial contributions. In the 1970s he was a pioneer in studying the mechanism of hormonal induction of oocyte maturation . His later research is focused in two ubiquitous protein kinases , CK1 and CK2, involved in the phosphorylation of key cellular proteins. [ 6 ]
He devoted much of his life to organizing activities for the scientific integration in Latin America especially through organizing series of training courses in molecular biology techniques, and through the creation of the Latin American Network of Biological Sciences. [ 7 ]
In recent years, Doctor Allende has been a promoter of science education through his personal commitment in several projects, like the Science Education Inquiry Based program, funded by the University of Chile, [ 8 ] and through his participation in the Allende-Connelly Foundation, founded by him and his wife. [ 9 ] [ 10 ]
Though he retired from active science in 2009, he remains a professor at the Faculty of Medicine. He was also Research Vice President of the University of Chile. [ 11 ] [ 12 ] He published his autobiography in 2010. [ 13 ]
He married Catherine Connelly (also a biochemist ) in Holyoke, Massachusetts , On September 16, 1961. He raised a family of four children: Miguel Luis, Juan Ignacio, Jorge Eduardo and Maria Amparo and has 13 grandchildren. [ 14 ]
With his wife, Catherine Connelly, he was on sabbatical at the University of California at San Diego , when the 1973 coup in Chile took place. He returned to Chile in May 1974 and was one of the main defenders of the University of Chile's autonomy, endangered by the military intervention in academic life. In December 1975 he co-signed, with other academics, a letter entitled "University under surveillance" opposing military intervention in the University of Chile. The letter was written by philosopher Jorge Millas and published in the newspaper " El Mercurio ". The letter was the first appearance of a public statement by a group of academics who criticized the handling of the University of Chile by the military government. [ 15 ] | https://en.wikipedia.org/wiki/Jorge_Allende |
Jorge Francisco Isidoro Luis Borges Acevedo ( / ˈ b ɔːr h ɛ s / BOR -hess ; [ 2 ] Spanish: [ˈxoɾxe ˈlwis ˈboɾxes] ⓘ ; 24 August 1899 – 14 June 1986) was an Argentine short-story writer , essayist, poet and translator regarded as a key figure in Spanish-language and international literature. His best-known works, Ficciones ( transl. Fictions ) and El Aleph ( transl. The Aleph ), published in the 1940s, are collections of short stories exploring motifs such as dreams , labyrinths , chance , infinity , archives , mirrors , fictional writers and mythology . [ 3 ] Borges's works have contributed to philosophical literature and the fantasy genre, [ citation needed ] and have had a major influence on the magical realist movement in 20th century Latin American literature . [ 4 ]
Born in Buenos Aires , Borges later moved with his family to Switzerland in 1914, where he studied at the Collège de Genève . The family travelled widely in Europe, including Spain. On his return to Argentina in 1921, Borges began publishing his poems and essays in surrealist literary journals. He also worked as a librarian and public lecturer . [ 5 ] In 1955, he was appointed director of the National Public Library and professor of English Literature at the University of Buenos Aires . He became completely blind by the age of 55. Scholars have suggested that his progressive blindness helped him to create innovative literary symbols through imagination. [ Note 1 ] By the 1960s, his work was translated and published widely in the United States and Europe. Borges himself was fluent in several languages.
In 1961, Borges came to international attention when he received the first Formentor Prize , which he shared with Samuel Beckett . In 1971, he won the Jerusalem Prize . His international reputation was consolidated in the 1960s, aided by the growing number of English translations, the Latin American Boom , and by the success of García Márquez 's One Hundred Years of Solitude . [ 6 ] He dedicated his final work, The Conspirators , to the city of Geneva , Switzerland. [ 7 ] Writer and essayist J. M. Coetzee said of him: "He, more than anyone, renovated the language of fiction and thus opened the way to a remarkable generation of Spanish-American novelists." [ 8 ] David Foster Wallace wrote: "The truth, briefly stated, is that Borges is arguably the great bridge between modernism and post-modernism in world literature... His stories are inbent and hermetic, with the oblique terror of a game whose rules are unknown and its stakes everything." [ 9 ]
Jorge Francisco Isidoro Luis Borges Acevedo was born into an educated middle-class family on 24 August 1899. [ 10 ] They lived in Palermo , a poor area of Buenos Aires. Borges's mother, Leonor Acevedo Suárez , worked as a translator and came from a family of criollo (Spanish) origin. Her family had been much involved in the European settling of South America and the Argentine War of Independence , and she spoke often of their heroic actions. [ 11 ]
His 1929 book Cuaderno San Martín includes the poem "Isidoro Acevedo", commemorating his grandfather, Isidoro de Acevedo Laprida, a soldier of the Buenos Aires Army. A descendant of the Argentine lawyer and politician Francisco Narciso de Laprida , Acevedo Laprida fought in the battles of Cepeda in 1859, Pavón in 1861, and Los Corrales in 1880. Acevedo Laprida died of pulmonary congestion in the house where his grandson Jorge Luis Borges was born. According to a study by Antonio Andrade, Jorge Luis Borges had Portuguese ancestry: Borges's great-grandfather, Francisco, was born in Portugal in 1770, and lived in Torre de Moncorvo , in the north of the country, before he emigrated to Argentina, where he married Carmen Lafinur.
Borges's own father, Jorge Guillermo Borges Haslam , was a lawyer and wrote the novel El caudillo in 1921. Borges Haslam was born in Entre Ríos of Spanish, Portuguese, and English descent, the son of Francisco Borges Lafinur, a colonel, and Frances Ann Haslam, an Englishwoman. Borges Haslam grew up speaking English at home. The family frequently traveled to Europe. Borges Haslam wedded Leonor Acevedo Suárez in 1898 and their children also included the painter Norah Borges , sister of Jorge Luis Borges. [ 11 ]
At age ten, Jorge Luis Borges translated Oscar Wilde 's The Happy Prince into Spanish. It was published in a local journal, but Borges's friends thought the real author was his father. [ 12 ] Borges Haslam was a lawyer and psychology teacher who harboured literary aspirations. Borges said his father "tried to become a writer and failed in the attempt", despite the 1921 opus El caudillo . Jorge Luis Borges wrote, "As most of my people had been soldiers and I knew I would never be, I felt ashamed, quite early, to be a bookish kind of person and not a man of action." [ 11 ]
Jorge Luis Borges was taught at home until the age of 11 and was bilingual in Spanish and English, reading Shakespeare in the latter at the age of twelve. [ 11 ] The family lived in a large house with an English library of over one thousand volumes; Borges would later remark that "if I were asked to name the chief event in my life, I should say my father's library." [ 13 ]
His father gave up practicing law due to the failing eyesight that would eventually affect his son. In 1914, the family moved to Geneva , Switzerland, and spent the next decade in Europe. [ 11 ] In Geneva, Borges Haslam was treated by an eye specialist, while his son and daughter attended school. Jorge Luis learned French, read Thomas Carlyle in English, and began to read philosophy in German. In 1917, when he was eighteen, he met writer Maurice Abramowicz and began a literary friendship that lasted for the remainder of his life. [ 11 ] He received his baccalauréat from the Collège de Genève in 1918. [ 14 ] [ Note 2 ] The Borges family decided that, due to political unrest in Argentina, they would remain in Switzerland during the war. After World War I , the family spent three years living in various cities: Lugano , Barcelona, Mallorca , Seville, and Madrid. [ 11 ] They remained in Europe until 1921.
At that time, Borges discovered the writings of Arthur Schopenhauer and Gustav Meyrink 's The Golem (1915), which became influential to his work. In Spain, Borges became a member of the avant-garde , anti- Modernismo Ultraist literary movement, inspired by Guillaume Apollinaire and Filippo Tommaso Marinetti , close to the Imagists . His first poem, "Hymn to the Sea", written in the style of Walt Whitman , was published in the magazine Grecia . [ 15 ] While in Spain, he met such noted Spanish writers as Rafael Cansinos Assens and Ramón Gómez de la Serna . [ 16 ]
In 1921, Borges returned with his family to Buenos Aires. He had little formal education, no qualifications and few friends. He wrote to a friend that Buenos Aires was now "overrun by arrivistes, by correct youths lacking any mental equipment, and decorative young ladies". [ 11 ] He brought with him the doctrine of Ultraism and launched his career, publishing surreal poems and essays in literary journals. In 1923, Borges first published his poetry, a collection called Fervor de Buenos Aires , and contributed to the avant-garde review Martín Fierro . Borges co-founded the journals Prisma , a broadsheet distributed largely by pasting copies to walls in Buenos Aires, and Proa . Later in life, Borges regretted some of these early publications, attempting to purchase all known copies to ensure their destruction. [ 17 ]
By the mid-1930s, he began to explore existential questions and fiction. He worked in a style that Argentine critic Ana María Barrenechea has called "irreality". Many other Latin American writers, such as Juan Rulfo , Juan José Arreola , and Alejo Carpentier , were investigating these themes, influenced by the phenomenology of Husserl and Heidegger . In this vein, Borges biographer Edwin Williamson underlines the danger of inferring an autobiographically inspired basis for the content or tone of certain of his works: books, philosophy, and imagination were as much a source of real inspiration to him as his own lived experience, if not more so. [ 11 ]
From the first issue, Borges was a regular contributor to Sur , founded in 1931 by Victoria Ocampo . It was then Argentina's most important literary journal and helped Borges find his fame. [ 18 ] Ocampo introduced Borges to Adolfo Bioy Casares , another well-known figure of Argentine literature who was to become a frequent collaborator and close friend. They wrote a number of works together, some under the nom de plume H. Bustos Domecq , including a parody detective series and fantasy stories. During these years, a family friend, Macedonio Fernández , became a major influence on Borges. The two would preside over discussions in cafés, at country retreats, or in Fernandez's tiny apartment in the Balvanera district. He appears by name in Borges's Dialogue about a Dialogue , [ 19 ] in which the two discuss the immortality of the soul.
In 1933, Borges gained an editorial appointment at Revista Multicolor de los Sábados (the literary supplement of the Buenos Aires newspaper Crítica ), where he first published the pieces collected as Historia universal de la infamia ( A Universal History of Infamy ) in 1935. [ 11 ] The book includes two types of writing: the first lies somewhere between non-fiction essays and short stories, using fictional techniques to tell essentially true stories. The second consists of literary forgeries, which Borges initially passed off as translations of passages from famous but seldom-read works.
In the following years, he served as a literary adviser for the publishing house Emecé Editores , and from 1936 to 1939 wrote weekly columns for El Hogar . In 1938, Borges found work as the first assistant at the Miguel Cané Municipal Library. It was in a working-class area [ 20 ] and there were so few books that cataloging more than one hundred books per day, he was told, would leave little to do for the other staff and would make them look bad. The task took him about an hour each day and the rest of his time he spent in the basement of the library, writing and translating. [ 11 ]
Borges's father died in 1938, shortly before his 64th birthday. On Christmas Eve that year, Borges had a severe head injury; during treatment, he nearly died of sepsis . [ 21 ] While recovering from the accident, Borges began exploring a new style of writing for which he would become famous. [ 22 ] His first story written after his accident, " Pierre Menard, Author of the Quixote ," came out in May 1939. One of his most famous works, "Menard", examines the nature of authorship, as well as the relationship between an author and his historical context. His first collection of short stories, El jardín de senderos que se bifurcan ( The Garden of Forking Paths ), appeared in 1941, composed mostly of works previously published in Sur . [ 11 ]
The title story concerns a Chinese professor in England, Dr. Yu Tsun, who spies for Germany during World War I, in an attempt to prove to the authorities that an Asian person is able to obtain the information that they seek. A combination of book and maze, it can be read in many ways. Through it, Borges arguably invented the hypertext novel and went on to describe a theory of the universe based upon the structure of such a novel. [ 23 ] [ 24 ]
Composed of stories taking up over sixty pages, the book was generally well received, but El jardín de senderos que se bifurcan failed to garner for him the literary prizes many in his circle expected. [ 25 ] [ 26 ] Victoria Ocampo dedicated a large portion of the July 1942 issue of Sur to a "Reparation for Borges". Numerous leading writers and critics from Argentina and throughout the Spanish-speaking world contributed writings to the "reparation" project.
With his vision beginning to fade in his early thirties and unable to support himself as a writer, Borges began a new career as a public lecturer. [ Note 3 ] [ 27 ] [ 28 ] He became an increasingly public figure, obtaining appointments as president of the Argentine Society of Writers and as professor of English and American Literature at the Argentine Association of English Culture. His short story " Emma Zunz " was made into a film (under the name of Días de odio , Days of Hate , directed in 1954 by Leopoldo Torre Nilsson ). [ 29 ] Around this time, Borges also began writing screenplays.
The American novelist William Faulkner was already a well-known writer in the Spanish-speaking world when Borges translated his novel The Wild Palms in 1940. Borges was a great admirer of Faulkner, but it is likely that his choice to translate a lesser novel was born out of opportunity and need. The novel had been published in the US in 1939, and Borges may have needed the money such work would bring. Nevertheless, his translation formed an indelible bridge between contemporary Latin American literature and the writer of the southern United States. Borges' intuitive understanding of and ability to render Faulkner's style was an important influence on a later generation of writers such as Juan Rulfo , Mario Vargas Llosa , and Gabriel García Márquez . [ 30 ] [ 31 ]
In 1955, Borges became director of the Argentine National Library. By the late 1950s he had become completely blind. Neither the coincidence nor the irony of his blindness as a writer escaped Borges: [ 11 ]
Nadie rebaje a lágrima o reproche esta declaración de la maestría de Dios, que con magnífica ironía me dio a la vez los libros y la noche.
(No one should read self-pity or reproach Into this statement of the majesty Of God; who with such splendid irony, At one touch granted me books and night.) [ 32 ]
His later collection of poetry, Elogio de la Sombra ( In Praise of Darkness ), [ 33 ] develops this theme. In 1956 the University of Cuyo awarded Borges the first of many honorary doctorates and the following year he received the National Prize for Literature. [ 34 ] From 1956 to 1970, Borges also held a position as a professor of literature at the University of Buenos Aires and other temporary appointments at other universities. [ 34 ] He received a British honorary knighthood in 1964. [ 35 ] In the fall of 1967 and spring of 1968, he delivered the Charles Eliot Norton Lectures at Harvard University . [ 36 ]
As his eyesight deteriorated, Borges relied increasingly on his mother's help. [ 34 ] When he was not able to read and write anymore (he never learned to read Braille ), his mother, to whom he had always been close, became his personal secretary. [ 34 ] When Perón returned from exile and was re-elected president in 1973, Borges immediately resigned as director of the National Library. [ 37 ]
Eight of Borges's poems appear in the 1943 anthology of Spanish American Poets by H. R. Hays. [ 38 ] [ Note 4 ] "The Garden of Forking Paths", one of the first Borges stories to be translated into English, appeared in the August 1948 issue of Ellery Queen's Mystery Magazine , translated by Anthony Boucher . [ 39 ] Though several other Borges translations appeared in literary magazines and anthologies during the 1950s (and one story appeared in the fantasy and science fiction magazine Fantastic Universe in 1960), [ 40 ] his international fame dates from the early 1960s. [ 41 ]
In 1961, Borges received the first Prix International , which he shared with Samuel Beckett . While Beckett had garnered a distinguished reputation in Europe and America, Borges had been largely unknown and untranslated in the English-speaking world and the prize stirred great interest in his work. The Italian government named Borges Commendatore and the University of Texas at Austin appointed him for one year to the Tinker Chair. This led to his first lecture tour in the United States. In 1962, two major anthologies of Borges's writings were published in English by New York presses: Ficciones and Labyrinths . In that year, Borges began lecture tours of Europe. Numerous honors were to accumulate over the years such as a Special Edgar Allan Poe Award from the Mystery Writers of America "for distinguished contribution to the mystery genre" (1976), [ 42 ] the Balzan Prize (for philology, linguistics and literary criticism) and the Prix mondial Cino Del Duca , the Miguel de Cervantes Prize (all 1980), as well as the French Legion of Honour (1983) and the Diamond Konex Award for Literature Arts as the most important writer in the last decade in his country.
In 1967, Borges began a five-year period of collaboration with the American translator Norman Thomas di Giovanni , through whom he became better known in the English-speaking world. [ 43 ] [ 44 ] [ 45 ] Di Giovanni contended that Borges's popularity was due to his writing with multiple languages in mind and deliberately using Latin words as a bridge from Spanish to English. [ 46 ]
Borges continued to publish books, among them El libro de los seres imaginarios ( Book of Imaginary Beings , 1967, co-written with Margarita Guerrero ), [ 47 ] El informe de Brodie ( Dr. Brodie's Report , 1970), [ 48 ] and El libro de arena ( The Book of Sand , 1975 [ 47 ] [ 48 ] ). He lectured prolifically. Many of these lectures were anthologized in volumes such as Siete noches ( Seven Nights ) [ 49 ] and Nueve ensayos dantescos ( Nine Dantesque Essays ). [ 50 ]
His presence in 1967 on campus at the University of Virginia (UVA) in the U.S. mirrored William Faulkner's tenure there ten years earlier as UVa's first writer-in-residence [ 51 ] and influenced a group of students among whom was Jared Loewenstein, who would later become founder and curator of the Jorge Luis Borges Collection at UVA, [ 52 ] one of the largest repositories of documents and manuscripts pertaining to Borges's early works. [ 53 ] In 1984, he travelled to Athens, Greece, and later to Rethymnon, Crete, where he was awarded an honorary doctorate from the School of Philosophy at the University of Crete . [ 54 ]
In the mid-1960s, Borges became acquainted with Jorge Mario Bergoglio, the future Pope Francis , who was at the time a young Jesuit priest. In 1979, Borges spoke appreciatively and at some length about Bergoglio to the Argentine poet and essayist Roberto Alifano. [ 55 ]
In 1967, Borges married the recently widowed Elsa Astete Millán. Friends believed that his mother, who was 90 and anticipating her own death, wanted to find someone to care for her blind son. The marriage lasted less than three years. After a legal separation, Borges moved back in with his mother, with whom he lived until her death at age 99. [ 56 ] Thereafter, he lived alone in the small flat he had shared with her, cared for by Fanny, their housekeeper of many decades. [ 57 ]
From 1975 until the time of his death, Borges traveled internationally. He was often accompanied in these travels by his personal assistant María Kodama , an Argentine woman of Japanese and German ancestry. In April 1986, a few months before his death, he married her via an attorney in Paraguay , in what was then a common practice among Argentines wishing to circumvent the Argentine laws of the time regarding divorce. According to Kodama, Borges drank as a young man, but eventually gave up alcohol as he aged and "felt more secure." [ 58 ] On his religious views, Borges declared himself an agnostic, clarifying: "Being an agnostic means all things are possible, even God, even the Holy Trinity. This world is so strange that anything may happen, or may not happen." [ 59 ] Borges was taught to read the Bible by his English Protestant grandmother and he prayed the Our Father each night because of a promise he made to his mother. He also died in the presence of a priest. [ 60 ]
During his final days in Geneva, Borges began brooding about the possibility of an afterlife . Although calm and collected about his own death, Borges began probing Kodama as to whether she inclined more towards the Shinto beliefs of her father or the Catholicism of her mother. Kodama "had always regarded Borges as an Agnostic, as she was herself", but given the insistence of his questioning, she offered to call someone more "qualified". [ 61 ] Borges responded, "You are asking me if I want a priest." He then instructed her to call two clergymen, a Catholic priest, in memory of his mother, and a Protestant minister, in memory of his English grandmother. He was visited first by Father Pierre Jacquet and by Pastor Edouard de Montmollin. [ 61 ]
Borges died of liver cancer on 14 June 1986, aged 86, in Geneva. His burial was preceded by an ecumenical service at the Protestant St. Pierre Cathedral on 18 June. With many Swiss and Argentine dignitaries present, Pastor de Montmollin read the First Chapter of St John's Gospel . He then preached that "Borges was a man who had unceasingly searched for the right word, the term that could sum up the whole, the final meaning of things." He said, however, that no man can reach that word through his own efforts and in trying becomes lost in a labyrinth. Pastor de Montmollin concluded, "It is not man who discovers the word, it is the Word that comes to him." [ 62 ]
Father Jacquet also preached, saying that, when visiting Borges before his death, he had found "a man full of love, who received from the Church the forgiveness of his sins". [ 62 ] [ 63 ] After the funeral, Borges was laid to rest in Geneva's Cimetière de Plainpalais . His grave, marked by a rough-hewn headstone, is adorned with carvings derived from Anglo-Saxon and Old Norse art and literature. [ 64 ]
Maria Kodama, his widow and heir on the basis of the marriage and two wills, gained control over his works. Her assertive administration of his estate resulted in a bitter dispute with the French publisher Gallimard regarding the republication of the complete works of Borges in French, with Pierre Assouline in Le Nouvel Observateur (August 2006) calling her "an obstacle to the dissemination of the works of Borges". Kodama took legal action against Assouline, considering the remark unjustified and defamatory, asking for a symbolic compensation of one euro. [ 65 ] [ 66 ] [ 67 ] Kodama also rescinded all publishing rights for existing collections of his work in English, including the translations by Norman Thomas di Giovanni , in which Borges himself had collaborated, and from which di Giovanni would have received an unusually high fifty percent of the royalties. Kodama commissioned new translations by Andrew Hurley , which have become the official translations in English. [ 68 ] At the time of her death, Kodama left no will and the status of the Borges estate is in limbo. [ citation needed ]
During the 1920s and 1930s, Borges was a vocal supporter of Hipólito Yrigoyen and the social democratic Radical Civic Union . [ 69 ] In 1945, Borges signed a manifesto calling for an end to military rule and the establishment of political liberty and democratic elections. [ 70 ] By the 1960s, he had grown more skeptical of democracy. During a 1971 conference at Columbia University , a creative writing student asked Borges what he regarded as "a writer's duty to his time". Borges replied, "I think a writer's duty is to be a writer, and if he can be a good writer, he is doing his duty. Besides, I think of my own opinions as being superficial. For example, I am a Conservative, I hate the Communists, I hate the Nazis, I hate the anti-Semites, and so on; but I don't allow these opinions to find their way into my writings—except, of course, when I was greatly elated about the Six-Day War . Generally speaking, I think of keeping them in watertight compartments. Everybody knows my opinions, but as for my dreams and my stories, they should be allowed their full freedom, I think. I don't want to intrude into them, I'm writing fiction, not fables." [ 71 ] In the 1980s, towards the end of his life, Borges regained his earlier faith in democracy and held it out as the only hope for Argentina. [ 70 ] In 1983, Borges applauded the election of the Radical Civic Union's Raúl Alfonsín and welcomed the end of military rule with the following words: "I once wrote that democracy is the abuse of statistics ... On October 30, 1983, Argentine democracy refuted me splendidly. Splendidly and resoundingly." [ 72 ] [ 73 ]
Borges recurrently declared himself a " Spencerian anarchist who believes in the individual and not in the State" due to his father's influence. [ 74 ] [ 75 ] [ 76 ] In an interview with Richard Burgin during the late 1960s, Borges described himself as a "mild" adherent of classical liberalism . He further recalled that his opposition to communism and to Marxism was absorbed in his childhood, stating: "Well, I have been brought up to think that the individual should be strong and the State should be weak. I couldn't be enthusiastic about theories where the State is more important than the individual." [ 77 ] After the overthrow via coup d'état of President Juan Domingo Perón in 1955, Borges supported efforts to purge Argentina's Government of Peronists and dismantle the former President's welfare state. He was enraged that the Communist Party of Argentina opposed these measures and sharply criticized them in lectures and in print. Borges's opposition to the Party in this matter ultimately led to a permanent rift with his longtime lover, Argentine Communist Estela Canto . [ 78 ]
In a 1956 interview given to El Hogar , Borges stated that communists "are in favor of totalitarian regimes and systematically combat freedom of thought, oblivious of the fact that the principal victims of dictatorships are, precisely, intelligence and culture." [ 79 ] He elaborated: "Many people are in favor of dictatorships because they allow them to avoid thinking for themselves. Everything is presented to them ready-made. There are even agencies of the State that supply them with opinions, passwords, slogans, and even idols to exalt or cast down according to the prevailing wind or in keeping with the directives of the thinking heads of the single party ." [ 80 ]
In later years, Borges frequently expressed contempt for Marxist and communist authors, poets, and intellectuals. In an interview with Burgin, Borges referred to Chilean poet Pablo Neruda as "a very fine poet" but a "very mean man" for unconditionally supporting the Soviet Union and demonizing the United States. Borges commented about Neruda, "Now he knows that's rubbish." [ 81 ] In the same interview, Borges also criticized famed poet and playwright Federico García Lorca , who was abducted by Nationalist soldiers and executed without trial during the Spanish Civil War . In Borges's opinion, Lorca's poetry and plays, when examined against his tragic death, appeared better than they actually were. [ 82 ]
In 1934, Argentine ultra-nationalists , sympathetic to Adolf Hitler and the Nazi Party , asserted Borges was secretly Jewish and by implication not truly Argentinian. Borges responded with the essay " Yo, Judío " ("I, a Jew"), a reference to the old phrase "Yo, Argentino" ("I, an Argentine") uttered by potential victims during pogroms against Argentine Jews to signify one was not Jewish. [ 83 ] In the essay, Borges declares he would be proud to be a Jew, and remarks that any pure Castilian is likely to come from ancient Jewish descent, from a millennium ago. [ 83 ] Both before and during the Second World War , Borges regularly published essays attacking the Nazi police state and its racist ideology. His outrage was fueled by his deep love for German literature . In an essay published in 1937, Borges attacked the Nazi Party's use of children's books to inflame antisemitism. He wrote, "I don't know if the world can do without German civilization, but I do know that its corruption by the teachings of hatred is a crime." [ 84 ]
In a 1938 essay, Borges reviewed an anthology which rewrote German authors of the past to fit the Nazi party line. He was disgusted by what he described as Germany's "chaotic descent into darkness" and the attendant rewriting of history. He argued that such books sacrificed the German people's culture, history and integrity in the name of restoring their national honour. Such use of children's books for propaganda he writes, "perfect the criminal arts of barbarians." [ 85 ] In a 1944 essay, Borges postulated,
Nazism suffers from unreality, like Erigena 's hell. It is uninhabitable; men can only die for it, lie for it, wound and kill for it. No one, in the intimate depths of his being, can wish it to triumph. I shall risk this conjecture: Hitler wants to be defeated . Hitler is blindly collaborating with the inevitable armies that will annihilate him, as the metal vultures and the dragon (which must have known that they were monsters) collaborated, mysteriously, with Hercules ." [ 86 ]
In 1946, Borges published the short story " Deutsches Requiem ", which masquerades as the last testament of a condemned Nazi war criminal named Otto Dietrich zur Linde. In a 1971 conference at Columbia University , Borges was asked about the story by a student from the creative writing program. He recalled, "When the Germans were defeated I felt great joy and relief, but at the same time I thought of the German defeat as being somehow tragic, because here we have perhaps the most educated people in Europe, who have a fine literature, a fine tradition of philosophy and poetry. Yet these people were bamboozled by a madman named Adolf Hitler , and I think there is tragedy there." [ 87 ]
In a 1967 interview with Burgin, Borges recalled how his interactions with Argentina's Nazi sympathisers led him to create the story. He recalled, "And then I realized that those people that were on the side of Germany, that they never thought of German victories or the German glory. What they really liked was the idea of the Blitzkrieg , of London being on fire, of the country being destroyed. As to the German fighters, they took no stock in them. Then I thought, well now Germany has lost, now America has saved us from this nightmare, but since nobody can doubt on which side I stood, I'll see what can be done from a literary point of view in favor of the Nazis. And then I created the ideal Nazi." [ 88 ]
At Columbia University in 1971, Borges further elaborated on the story's creation, "I tried to imagine what a real Nazi might be like. I mean someone who thought of violence as being praiseworthy for its own sake. Then I thought that this archetype of the Nazis wouldn't mind being defeated; after all, defeats and victories are mere matters of chance. He would still be glad of the fact, even if the Americans and British won the war. Naturally, when I am with Nazis, I find they are not my idea of what a Nazi is, but this wasn't meant to be a political tract. It was meant to stand for the fact that there was something tragic in the fate of a real Nazi. Except that I wonder if a real Nazi ever existed. At least, when I went to Germany, I never met one. They were all feeling sorry for themselves and wanted me to feel sorry for them as well." [ 89 ]
In 1946, Argentine President Juan Perón began transforming Argentina into a one-party state with the assistance of his wife, Evita . Almost immediately, the spoils system was the rule of the day, as ideological critics of the ruling Partido Justicialista were fired from government jobs. During this period, Borges was informed that he was being "promoted" from his position at the Miguel Cané Library to a post as inspector of poultry and rabbits at the Buenos Aires municipal market. Upon demanding to know the reason, Borges was told, "Well, you were on the side of the Allies, what do you expect?" [ 90 ] Borges resigned the following day. Perón's treatment of Borges became a cause célèbre for the Argentine intelligentsia. The Argentine Society of Writers (SADE) held a formal dinner in his honour. At the dinner, a speech was read which Borges had written for the occasion. It said:
Dictatorships breed oppression, dictatorships breed servility, dictatorships breed cruelty; more loathsome still is the fact that they breed idiocy. Bellboys babbling orders, portraits of caudillos , prearranged cheers or insults, walls covered with names, unanimous ceremonies, mere discipline usurping the place of clear thinking ... Fighting these sad monotonies is one of the duties of a writer. Need I remind readers of Martín Fierro or Don Segundo that individualism is an old Argentine virtue. [ 91 ]
In the aftermath, Borges found himself much in demand as a lecturer and one of the intellectual leaders of the Argentine opposition. In 1951 he was asked by anti-Peronist friends to run for president of SADE. Borges, then having depression caused by a failed romance, reluctantly accepted. He later recalled that he would awake every morning and remember that Perón was president and feel deeply depressed and ashamed. [ 92 ] Perón's government had seized control of the Argentine mass media and regarded SADE with indifference. Borges later recalled, however, "Many distinguished men of letters did not dare set foot inside its doors." [ 93 ] Meanwhile, SADE became an increasing refuge for critics of the Perón government. SADE official Luisa Mercedes Levinson noted, "We would gather every week to tell the latest jokes about the ruling couple and even dared to sing the songs of the French Resistance , as well as ' La Marseillaise '". [ 93 ]
After Evita Perón's death on 26 July 1952, Borges received a visit from two policemen, who ordered him to put up two portraits of the ruling couple on the premises of SADE. Borges indignantly refused, calling it a ridiculous demand. The policemen replied that he would soon face the consequences. [ 94 ] The Justicialist Party placed Borges under 24-hour surveillance and sent policemen to sit in on his lectures; in September they ordered SADE to be permanently closed down. Like much of the Argentine opposition to Perón, SADE had become marginalized due to persecution by the State, and very few active members remained. [ 95 ] According to Edwin Williamson,
Borges had agreed to stand for the presidency of the SADE in order [to] fight for intellectual freedom, but he also wanted to avenge the humiliation he believed he had suffered in 1946, when the Peronists had proposed to make him an inspector of chickens. In his letter of 1950 to Attilio Rossi , he claimed that his infamous promotion had been a clever way the Peronists had found of damaging him and diminishing his reputation. The closure of the SADE meant that the Peronists had damaged him a second time, as was borne out by the visit of the Spanish writer Julián Marías , who arrived in Buenos Aires shortly after the closure of the SADE. It was impossible for Borges, as president, to hold the usual reception for the distinguished visitor; instead, one of Borges's friends brought a lamb from his ranch, and they had it roasted at a tavern across the road from the SADE building on Calle Mexico. After dinner, a friendly janitor let them into the premises, and they showed Marías around by candlelight. That tiny group of writers leading a foreign guest through a dark building by the light of guttering candles was vivid proof of the extent to which the SADE had been diminished under the rule of Juan Perón. [ 96 ]
On 16 September 1955, General Pedro Eugenio Aramburu 's Revolución Libertadora toppled the ruling party and forced Perón into exile. Borges was overjoyed and joined demonstrators marching through the streets of Buenos Aires. According to Williamson, Borges shouted, "Viva la Patria", until his voice grew hoarse. Due to the influence of Borges's mother and his own role on the opposition to Peron, the provisional government appointed Borges as the Director of the National Library . [ 97 ]
In his essay L'Illusion Comique , Borges wrote there were two histories of Peronism in Argentina. The first he described as "the criminal one", composed of the police state tactics used against both real and imagined anti-Peronists. The second history was, according to Borges, "the theatrical one" composed of "tales and fables made for consumption by dolts." He argued that, despite their claims to detest capitalism, Juan and Eva Perón "copied its methods, dictating names and slogans to the people" in the same way that multi-national corporations "impose their razor blades, cigarettes, and washing machines." Borges then listed the numerous conspiracy theories the ruling couple dictated to their followers and how those theories were accepted without question. [ 98 ] Borges concluded:
It is useless to list the examples; one can only denounce the duplicity of the fictions of the former regime, which can't be believed and were believed. It will be said that the public's lack of sophistication is enough to explain the contradiction; I believe that the cause is more profound. Coleridge spoke of the "willing suspension of disbelief ," that is, poetic faith; Samuel Johnson said, in defense of Shakespeare, that the spectators at a tragedy do not believe they are in Alexandria in the first act and Rome in the second but submit to the pleasure of a fiction. Similarly, the lies of a dictatorship are neither believed nor disbelieved; they pertain to an intermediate plane, and their purpose is to conceal or justify sordid or atrocious realities. They pertain to the pathetic or the clumsily sentimental. Happily, for the enlightenment and security of the Argentines, the current regime has understood that the function of government is not to inspire pathos. [ 99 ]
In a 1967 interview, Borges said, "Perón was a humbug, and he knew it, and everybody knew it. But Perón could be very cruel. I mean, he had people tortured, killed. And his wife was a common prostitute." [ 100 ] When Perón returned from exile in 1973 and regained the Presidency, Borges was enraged. In a 1975 interview for National Geographic , he said "Damn, the snobs are back in the saddle. If their posters and slogans again defile the city, I'll be glad I've lost my sight. Well, they can't humiliate me as they did before my books sold well." [ 101 ]
After being accused of being unforgiving, Borges quipped, "I resented Perón's making Argentina look ridiculous to the world ... as in 1951, when he announced control over thermonuclear fusion , which still hasn't happened anywhere but in the sun and the stars. For a time, Argentines hesitated to wear band aids for fear friends would ask, 'Did the atomic bomb go off in your hand?' A shame, because Argentina really has world-class scientists." [ 101 ] After Borges's death in 1986, the Peronist Partido Justicialista declined to send a delegate to the writer's memorial service in Buenos Aires. A spokesman for the Party said that this was in reaction to "certain declarations he had made about the country." [ 102 ] Later, at the City Council of Buenos Aires, Peronist politicians refused to honor Borges as an Argentine, commenting that he "chose to die abroad." When infuriated politicians from the other parties demanded to know the real reason, the Peronists finally explained that Borges had made statements about Evita Perón which they called "unacceptable". [ 102 ]
During the 1970s, Borges at first expressed support for Argentina's military junta , but was scandalized by the junta's actions during the Dirty War . In protest against their support of the regime, Borges ceased publishing in the newspaper La Nación . [ 103 ] In 1985, he wrote a short poem about the Falklands War called Juan López y John Ward , about two fictional soldiers (one from each side), who died in the Falklands, in which he refers to "islands that were too famous". He also said about the war: "The Falklands thing was a fight between two bald men over a comb." [ 104 ]
Borges was an observer at the trials of the military junta in 1985 and wrote that "not to judge and condemn the crimes would be to encourage impunity and to become, somehow, its accomplice." [ 72 ] Borges added that "the news of the missing people, the crimes and atrocities [the military] committed" had inspired him to return to his earlier Emersonian faith in democracy. [ 72 ]
Borges believed that indigenous peoples in what is now called Argentina had no traditions: "There's no native tradition of any kind since the Indians here were mere barbarians. We have to fall back on the European tradition, why not? It's a very fine tradition." [ 105 ]
Wardrip-Fruin and Montfort argue that Borges "may have been the most important figure in Spanish-language literature since Cervantes . He was clearly of tremendous influence, writing intricate poems, short stories, and essays that instantiated concepts of dizzying power." [ 106 ] Borges's work has been compared to that of Homer and Milton . [ 107 ] Indeed, the critic Harold Bloom numbers Borges among the key figures of the Western literary canon . [ 108 ]
In addition to short stories, for which he is most noted, Borges also wrote poetry, essays, screenplays, and literary criticism, and edited numerous anthologies. His longest work of fiction is a fourteen-page story, "The Congress", first published in 1971. [ 11 ] His late-onset blindness strongly influenced his later writing. Borges wrote: "When I think of what I've lost, I ask, 'Who know themselves better than the blind?' – for every thought becomes a tool." [ 109 ] Paramount among his intellectual interests were elements of mythology, mathematics, theology, integrating these through literature, sometimes playfully, sometimes with great seriousness. [ 110 ]
Borges composed poetry throughout his life. As his eyesight waned (it came and went, with a struggle between advancing age and advances in eye surgery), he increasingly focused on writing poetry, since he could memorize an entire work in progress. [ 111 ] His poems embrace the same wide range of interests as his fiction, along with issues that emerge in his critical works and translations, and from more personal musings. For example, his interest in idealism runs through his work, reflected in the fictional world of Tlön in " Tlön, Uqbar, Orbis Tertius " and in his essay " A New Refutation of Time ". [ 112 ]
Borges was a notable translator. He translated works of literature in English, French, German, Old English , and Old Norse into Spanish. His first publication, for a Buenos Aires newspaper, was a translation of Oscar Wilde 's story " The Happy Prince " into Spanish when he was ten. [ 12 ] At the end of his life he produced a Spanish-language version of a part of Snorri Sturluson 's Prose Edda . He also translated (while simultaneously subtly transforming) the works of, among others, Ambrose Bierce , William Faulkner , [ 113 ] André Gide , Hermann Hesse , Franz Kafka , Rudyard Kipling , Edgar Allan Poe , Walt Whitman , and Virginia Woolf . [ Note 5 ] Borges wrote and lectured extensively on the art of translation, holding that a translation may improve upon the original, may even be unfaithful to it, and that alternative and potentially contradictory renderings of the same work can be equally valid. [ 114 ] Borges employed the devices of literary forgery and the review of an imaginary work, both forms of modern pseudo-epigrapha .
Borge’s recorded work includes readings of his poems, a collaboration with Argentine composer Astor Piazzolla , and a series of lectures on a characteristically wide range of topics, from Buddhism to the nature of poetry. [ 115 ]
Polydor – 20291
AMB Discografica – 123 – 1
Universidad Nacional Autonoma De Mexico – VVAL-13, UNAM-113/114
de Souza, Marcelo Mendes. “Unoriginal Opinions of an Original Man: Jorge Luis Borges’s Views on Race and Brazilian People in His Conversations with Adolfo Bioy Casares and His Literary Works.” Latin American research review 56.3 (2021): 668–678. Web. [ 116 ]
Microfon – SUP 955
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Borges's best-known set of literary forgeries date from his early work as a translator and literary critic with a regular column in the Argentine magazine El Hogar . Along with publishing numerous legitimate translations, he also published original works, for example, in the style of Emanuel Swedenborg [ Note 6 ] or One Thousand and One Nights , originally claiming them to be translations of works he had chanced upon. In another case, he added three short, falsely attributed pieces into his otherwise legitimate and carefully researched anthology El matrero . [ Note 6 ] Several of these are gathered in A Universal History of Infamy . While Borges was the great popularizer of the review of an imaginary work, he had developed the idea from Thomas Carlyle 's Sartor Resartus , a book-length review of a non-existent German transcendentalist work, and the biography of its equally non-existent author. In This Craft of Verse , Borges says that in 1916 in Geneva "[I] discovered, and was overwhelmed by, Thomas Carlyle. I read Sartor Resartus , and I can recall many of its pages; I know them by heart." [ 117 ]
In the introduction to his first published volume of fiction, The Garden of Forking Paths , Borges remarks, "It is a laborious madness and an impoverishing one, the madness of composing vast books, setting out in five hundred pages an idea that can be perfectly related orally in five minutes. The better way to go about it is to pretend that those books already exist, and offer a summary, a commentary on them." He then cites both Sartor Resartus and Samuel Butler 's The Fair Haven , remarking, however, that "those works suffer under the imperfection that they themselves are books, and not a whit less tautological than the others. A more reasonable, more inept, and more lazy man, I have chosen to write notes on imaginary books." [ 118 ] On the other hand, some works were wrongly attributed to Borges, like the poem "Instantes" . [ 119 ] [ 120 ]
Borges's change in style from regionalist criollismo to a more cosmopolitan style brought him much criticism from journals such as Contorno , a leftist, Sartre-influenced Argentine publication founded by David Viñas and his brother, along with other intellectuals such as Noé Jitrik and Adolfo Prieto. In the post-Peronist Argentina of the early 1960s, Contorno met with wide approval from the youth who challenged the authenticity of older writers such as Borges and questioned their legacy of experimentation. Magic realism and exploration of universal truths, they argued, had come at the cost of responsibility and seriousness in the face of society's problems. [ 121 ] The Contorno writers acknowledged Borges and Eduardo Mallea for being "doctors of technique" but argued that their work lacked substance due to their lack of interaction with the reality that they inhabited, an existentialist critique of their refusal to embrace existence and reality in their artwork. [ 121 ]
The story " The Sect of the Phoenix " is famously interpreted to allude to the ubiquity of sexual intercourse among humans [ 122 ] – a concept whose essential qualities the narrator of the story is not able to relate to. With a few notable exceptions, women are almost entirely absent from Borges's fiction. [ 123 ] However, there are some instances in Borges's later writings of romantic love, for example the story " Ulrikke " from The Book of Sand . The protagonist of the story "El muerto" also lusts after the "splendid, contemptuous, red-haired woman" of Azevedo Bandeira [ 124 ] : 197 and later "sleeps with the woman with shining hair". [ 124 ] : 200 Although they do not appear in the stories, women are significantly discussed as objects of unrequited love in his short stories "The Zahir" and "The Aleph". [ 124 ] [ page needed ] The plot of La Intrusa was based on a true story of two friends. Borges turned their fictional counterparts into brothers, excluding the possibility of a homosexual relationship. [ 125 ]
" Emma Zunz " is a story with an eminent female protagonist. Originally published in 1948, this work tells the tale of a young Jewish woman who kills a man in order to avenge the disgrace and suicide of her father. She carefully plans the crime, submitting to an unpleasant sexual encounter with a stranger in order to create the appearance of sexual impropriety in her intended victim. Despite the fact that she premeditates and executes a murder, the eponymous heroine of this story is surprisingly likable, both because of intrinsic qualities in the character (interestingly enough, she believes in nonviolence) and because the story is narrated from a "remote but sympathetic" point of view that highlights the poignancy of her situation. [ 126 ]
Borges was never awarded the Nobel Prize in Literature , something which continually distressed the writer. [ 11 ] He was one of several distinguished authors who never received the honour. [ 127 ] Borges commented, "Not granting me the Nobel Prize has become a Scandinavian tradition; since I was born they have not been granting it to me." [ 128 ] Some observers speculated that Borges did not receive the award in his later life because of his conservative political views, or more specifically because he had accepted an honour from Chilean dictator Augusto Pinochet . [ 129 ] [ 130 ]
Borges was nominated for the Nobel Prize in Literature over thirty times, [ 131 ] and was among the short-listed candidates several times. In 1965 he was considered along with Vladimir Nabokov , Pablo Neruda , and Mikhail Sholokhov , and in 1966 a shared prize to Borges and Miguel Ángel Asturias was proposed. [ 132 ] Borges was nominated again in 1967, and was among the final three choices considered by the committee according to Nobel records unsealed on the 50th anniversary in 2017. The committee considered Borges, Graham Greene and Miguel Ángel Asturias , choosing Asturias as the winner. [ 133 ]
Many of Borges's best-known stories deal with themes of time (" The Secret Miracle "), infinity (" The Aleph "), mirrors (" Tlön, Uqbar, Orbis Tertius ") and labyrinths (" The Two Kings and the Two Labyrinths ", " The House of Asterion ", " The Immortal ", and " The Garden of Forking Paths "). Williamson writes, "His basic contention was that fiction did not depend on the illusion of reality; what mattered ultimately was an author's ability to generate 'poetic faith' in his reader." [ 11 ]
His stories often have fantastical themes, such as a library containing every possible 410-page text (" The Library of Babel "), a man who forgets nothing he experiences (" Funes, the Memorious "), an artifact through which the user can see everything in the universe ("The Aleph"), and a year of still time given to a man standing before a firing squad ("The Secret Miracle"). Borges told realistic stories of South American life, of folk heroes, street fighters, soldiers, gauchos , detectives, and historical figures. He mixed the real and the fantastic, fact with fiction. His interest in compounding fantasy, philosophy, and the art of translation are evident in articles such as "The Translators of The Book of One Thousand and One Nights ". In the Book of Imaginary Beings , a thoroughly researched bestiary of mythical creatures, Borges wrote, "There is a kind of lazy pleasure in useless and out-of-the-way erudition." [ 134 ] Borges's interest in fantasy was shared by Bioy Casares, with whom he coauthored several collections of tales between 1942 and 1967. [ citation needed ]
Often, especially early in his career, the mixture of fact and fantasy crossed the line into the realm of hoax or literary forgery. [ Note 6 ] "The Garden of Forking Paths" (1941) presents the idea of forking paths through networks of time, none of which is the same, all of which are equal. Borges uses the recurring image of "a labyrinth that folds back upon itself in infinite regression" so we "become aware of all the possible choices we might make." [ 135 ] The forking paths have branches to represent these choices that ultimately lead to different endings. Borges saw man's search for meaning in a seemingly infinite universe as fruitless and instead uses the maze as a riddle for time, not space. [ 135 ] He examined the themes of universal randomness (" The Lottery in Babylon ") and madness (" The Zahir "). Due to the success of the "Forking Paths" story, the term "Borgesian" came to reflect a quality of narrative non-linearity . [ Note 7 ]
John Clute writes: "as was earlier the case with Franz Kafka , a collection of whose work he translated as La Metamorfosis (coll. 1938), Borges's influence on twentieth century literature worldwide has been so deep and pervasive that any sf written in English since about 1960 may consciously or subliminally reflect his work. Any sf story whose structure or arguments question or play with the nature of reality – or which makes fantastic use of images of the Labyrinth, the Mirror, the Library, the Map, and/or the Book and/or the Dream to inform the world – will necessarily navigate seas of imagination he has already plumbed, apodictically, in ten or twenty short stories." Clute notes that Borges "revealed a first-hand (if at points inaccurate) knowledge of sf and its authors, including H. P. Lovecraft , Robert A Heinlein , A. E. van Vogt and Ray Bradbury " and cites Philip K. Dick , Thomas Pynchon , Kurt Vonnegut and Gene Wolfe as being directly influenced by Borges. [ 136 ]
William Gibson recalls "the sensation, both complex and eerily simple", of reading " Tlön, Uqbar, Orbis Tertius " in Labyrinths as a young man, seated at a writing desk said to have belonged to Francis Marion :
Had the concept of software been available to me, I imagine I would have felt as though I were installing something that exponentially increased what one day would be called bandwidth, though bandwidth of what , exactly, I remain unable to say. This sublime and cosmically comic fable of utterly pure information (i.e. the utterly fictive) gradually and relentlessly infiltrating and eventually consuming the quotidian, opened something within me which has never yet closed... Works we all our lives recall reading for the first time are among the truest milestones, but Labyrinths was a profoundly singular one, for me, and I believe I knew that, then, in my early adolescence. It was demonstrated to me, that afternoon. Proven. For, by the time I had finished with "Tlön" (though one never finishes with Tlön, nor indeed any story by Borges) and had traversed " The Garden of Forking Paths " and had wondered, literally bug-eyed, at " Pierre Menaud, Author of the Quixote ", I discovered that I had ceased to be afraid of any influence that might dwell within Francis Marion's towering desk." [ 137 ]
The philosophical term "Borgesian conundrum" is named after him and has been defined as the ontological question of "whether the writer writes the story, or it writes him." [ 138 ] The original concept was put forward by Borges in his essay "Kafka and His Precursors". After reviewing works that were written before those of Kafka, Borges wrote:
If I am not mistaken, the heterogeneous pieces I have enumerated resemble Kafka; if I am not mistaken, not all of them resemble each other. The second fact is the more significant. In each of these texts we find Kafka's idiosyncrasy to a greater or lesser degree, but if Kafka had never written a line, we would not perceive this quality; in other words, it would not exist. The poem "Fears and Scruples" by Browning foretells Kafka's work, but our reading of Kafka perceptibly sharpens and deflects our reading of the poem. Browning did not read it as we do now. In the critics' vocabulary, the word 'precursor' is indispensable, but it should be cleansed of all connotation of polemics or rivalry. The fact is that every writer creates his own precursors. His work modifies our conception of the past, as it will modify the future." [ 139 ]
Along with other young Argentine writers of his generation, Borges initially rallied around the fictional character of Martín Fierro. Martín Fierro , a poem by José Hernández , was a dominant work of 19th-century Argentine literature . Its eponymous hero became a symbol of Argentine sensibility, untied from European values – a gaucho , free, poor, pampas -dwelling. [ 140 ] The character Fierro is illegally drafted to serve at a border fort to defend it against the indigenous population but ultimately deserts to become a gaucho matrero , the Argentine equivalent of a North American western outlaw. Borges contributed keenly to the avant garde Martín Fierro magazine in the early 1920s. [ 141 ]
As Borges matured, he came to a more nuanced attitude toward the Hernández poem. In his book of essays on the poem, Borges separates his admiration for the aesthetic virtues of the work from his mixed opinion of the moral virtues of its protagonist. [ 142 ] In his essay "The Argentine Writer and Tradition" (1951), Borges celebrates how Hernández expresses the Argentine character. In a key scene in the poem, Martín Fierro and El Moreno compete by improvising songs on universal themes such as time, night, and the sea, reflecting the real-world gaucho tradition of payadas , improvised musical dialogues on philosophical themes. [ 140 ] [ 143 ] Borges points out that Hernández evidently knew the difference between actual gaucho tradition of composing poetry versus the "gauchesque" fashion among Buenos Aires literati. [ 144 ]
In his works he refutes the arch-nationalist interpreters of the poem and disdains others, such as critic Eleuterio Tiscornia, for their Europeanising approach. Borges denies that Argentine literature should distinguish itself by limiting itself to "local colour", which he equates with cultural nationalism. [ 143 ] Racine and Shakespeare 's work, he says, looked beyond their countries' borders. Neither, he argues, need the literature be bound to the heritage of old-world Spanish or European tradition. Nor should it define itself by the conscious rejection of its colonial past. He asserts that Argentine writers need to be free to define Argentine literature anew, writing about Argentina and the world from the point of view of those who have inherited the whole of world literature. [ 143 ] Williamson says "Borges's main argument is that the very fact of writing from the margins provides Argentine writers with a special opportunity to innovate without being bound to the canons of the centre, ... at once a part of and apart from the centre, which gives them much potential freedom". [ 140 ]
Borges focused on universal themes, but also composed a substantial body of literature on themes from Argentine folklore and history. His first book, the poetry collection Fervor de Buenos Aires ( Passion for Buenos Aires ), appeared in 1923. Borges's writings on things Argentine include Argentine culture ("History of the Tango"; "Inscriptions on Horse Wagons"), folklore ("Juan Muraña", "Night of the Gifts"), literature ("The Argentine Writer and Tradition", "Almafuerte"; " Evaristo Carriego "), and national concerns ("Celebration of the Monster", "Hurry, Hurry", "The Mountebank", "Pedro Salvadores"). Ultranationalists, however, continued to question his Argentine identity. [ 145 ] Borges's interest in Argentine themes reflects in part the inspiration of his family tree. Borges had an English paternal grandmother who, around 1870, married the criollo Francisco Borges, a man with a military command and a historic role in the Argentine Civil Wars in what are now Argentina and Uruguay . [ 146 ] [ 147 ] [ 148 ]
Spurred by pride in his family's heritage, Borges often used those civil wars as settings in fiction and quasi-fiction (for example, "The Life of Tadeo Isidoro Cruz", "The Dead Man", "Avelino Arredondo") as well as poetry ("General Quiroga Rides to His Death in a Carriage"). Borges's maternal great-grandfather, Manuel Isidoro Suárez , was another military hero, whom Borges immortalized in the poem "A Page to Commemorate Colonel Suárez, Victor at Junín". [ 149 ] His nonfiction explores many of the themes found in his fiction. Essays such as "The History of the Tango " or his writings on the epic poem " Martín Fierro " explore Argentine themes, such as the identity of the Argentine people and of various Argentine subcultures. The varying genealogies of characters, settings, and themes in his stories, such as "La muerte y la brújula", used Argentine models without pandering to his readers or framing Argentine culture as "exotic". [ 145 ]
In fact, contrary to what is usually supposed, the geographies found in his fictions often do not correspond to those of real-world Argentina. [ 150 ] In his essay "El escritor argentino y la tradición", Borges notes that the very absence of camels in the Qur'an was proof enough that it was an Arabian work, despite the fact that camels are mentioned in the Qur'an. He suggested that only someone trying to write an "Arab" work would purposefully include a camel. [ 145 ] He uses this example to illustrate how his dialogue with universal existential concerns was just as Argentine as writing about gauchos and tangos. [ citation needed ] Borges detested football . [ 151 ]
At the time of the Argentine Declaration of Independence in 1816, the population was predominantly criollo (of Spanish ancestry). From the mid-1850s on, waves of immigration from Europe, especially Italy and Spain, arrived in the country, and in the following decades the Argentine national identity diversified. [ 11 ] [ 152 ] Borges was writing in a strongly European literary context, immersed in Spanish, English, French, German, Italian, Anglo-Saxon and Old Norse literature. He also read translations of Near Eastern and Far Eastern works. Borges's writing is also informed by scholarship of Christianity , Buddhism, Islam , and Judaism , including prominent religious figures, heretics, and mystics. [ 153 ] Religion and heresy are explored in such stories as " Averroes's Search ", " The Writing of the God ", " The Theologians ", and " Three Versions of Judas ". The curious inversion of mainstream Christian concepts of redemption in the last story is characteristic of Borges's approach to theology in his literature. [ 154 ] In describing himself, Borges said, "I am not sure that I exist, actually. I am all the writers that I have read, all the people that I have met, all the women that I have loved; all the cities that I have visited, all my ancestors." [ 128 ] As a young man, he visited the frontier pampas which extend beyond Argentina into Uruguay and Brazil . Borges said that his father wished him "to become a citizen of the world, a great cosmopolitan," in the way of Henry and William James . [ 155 ]
Borges lived and studied in Switzerland and Spain as a young student. As Borges matured, he traveled through Argentina as a lecturer and, internationally, as a visiting professor; he continued to tour the world as he grew older, finally settling in Geneva , where he had spent some of his youth. Drawing on the influence of many times and places, Borges's work belittled nationalism and racism. [ 145 ] However, Borges also scorned his own Basque ancestry and criticised the abolition of slavery in America because he believed black people were happier remaining uneducated and without freedom. [ 156 ] Portraits of diverse coexisting cultures characteristic of Argentina are especially pronounced in the book Six Problems for don Isidoro Parodi (co-authored with Bioy Casares) and Death and the Compass . Borges wrote that he considered Mexican writer Alfonso Reyes to be "the best prose-writer in the Spanish language of any time." [ 157 ] Borges was also an admirer of Asian culture, e.g. the ancient Chinese board game of Go , about which he penned some verses, [ 158 ] while " The Garden of Forking Paths " had a strong Chinese theme.
Borges was rooted in the Modernism predominant in its early years and was influenced by Symbolism . [ 159 ] Like Vladimir Nabokov and James Joyce , he combined an interest in his native culture with broader perspectives, also sharing their multilingualism and inventiveness with language. However, while Nabokov and Joyce tended toward progressively larger works, Borges remained a miniaturist. His work progressed away from what he referred to as "the baroque": his later style is far more transparent and naturalistic than his earlier works. Borges represented the humanist view of media that stressed the social aspect of art driven by emotion. If art represented the tool, then Borges was more interested in how the tool could be used to relate to people. [ 106 ]
Existentialism saw its apogee during the years of Borges's greatest artistic production. It has been argued that his choice of topics largely ignored existentialism's central tenets. Critic Paul de Man notes, "Whatever Borges's existential anxieties may be, they have little in common with Sartre's robustly prosaic view of literature, with the earnestness of Camus' moralism, or with the weighty profundity of German existential thought. Rather, they are the consistent expansion of a purely poetic consciousness to its furthest limits." [ 160 ]
The essay collection Borges y la Matemática (Borges and Mathematics, 2003) by Argentine mathematician and writer Guillermo Martínez outlines how Borges used concepts from mathematics in his work. Martínez states that Borges had, for example, at least a superficial knowledge of set theory , which he handles with elegance in stories such as " The Book of Sand ". [ 161 ] Other books such as The Unimaginable Mathematics of Borges' Library of Babel by William Goldbloom Bloch (2008) and Unthinking Thinking: Jorge Luis Borges, Mathematics, and the New Physics by Floyd Merrell (1991) also explore this relationship.
Fritz Mauthner , philosopher of language and author of the Wörterbuch der Philosophie ( Dictionary of Philosophy ), had an important influence on Borges. Borges always recognized the influence of this German philosopher. [ 162 ] According to the literary review Sur , the book was one of the five books most noted and read by Borges. The first time that Borges mentioned Mauthner was in 1928 in his book The language of the Argentines (El idioma de los argentinos). In a 1962 interview Borges described Mauthner as possessing a fine sense of humor as well as great knowledge and erudition. [ 163 ]
In an interview, [ 164 ] Denis Dutton asked Borges who were the "philosophers who have influenced your works, in whom you've been the most interested". In reply, Borges named Berkeley and Schopenhauer . He was also influenced by Spinoza , about whom Borges wrote a famous poem. [ 165 ] It is not without humour that Borges once wrote: "Siempre imaginé que el Paraíso sería algún tipo de biblioteca." ("I always imagined Paradise to be some kind of a library.") [ 166 ] | https://en.wikipedia.org/wiki/Jorge_Luis_Borges |
Jorma Johannes Rissanen (October 20, 1932 – May 9, 2020) [ 2 ] was an information theorist , known for originating the minimum description length (MDL) principle and practical approaches to arithmetic coding for lossless data compression . His work inspired the development of the theory of stochastic chains with memory of variable length . [ 3 ] [ 2 ]
Rissanen was born in Pielisjärvi (now Lieksa ) in Finland and grew up in Kemi , a border town between Finland and Sweden. He moved to Helsinki and studied at the Helsinki University of Technology , where he obtained his Master’s degree in electrical engineering in 1956 and licentiate in control theory in 1960. He studied there under Olli Lokki and Hans Blomberg . [ 2 ]
Rissanen became an IBM researcher since 1960, first in Stockholm, Sweden , while still a Ph.D. student under Hans Blomberg. Most of his PhD work was done remotely as a result and he received his Ph.D. from the Helsinki University of Technology in 1965 with a topic on adaptive control theory . He then moved to IBM Almaden in San Jose, California and stayed with IBM until his retirement in 2002, with a brief interruption in 1974 as a professor of control theory at Linköping University in Sweden. During that time, he became familiar with the work on algorithmic randomness by Andrey Kolmogorov and Per Martin-Löf , which inspired his work on arithmetic coding and MDL, leading to a stream of ground-breaking publications from the late 1970s to the early 1990s. The work on MDL developed into the more general notions of stochastic complexity (about which he wrote an influential book [ 4 ] ) and universal coding /modeling. After retirement from IBM, he remained professor emeritus of Tampere University of Technology and a fellow of Helsinki Institute for Information Technology .
He was awarded the IEEE Richard W. Hamming Medal in 1993, [ 5 ] an IEEE Golden Jubilee Award for Technological Innovation from the IEEE Information Theory Society in 1998, [ 6 ] the Kolmogorov Medal of the University of London in 2006, [ 7 ] and the IEEE Claude E. Shannon Award in 2009. [ 8 ] A Festschrift collection, which includes an interview and substantial biographical information, was published by the Tampere University of Technology in honor of his 75th birthday. [ 1 ]
Rissanen married Riitta Aberg in 1956, and they have a son Juhani and a daughter Natasha. [ 1 ]
This article about a Finnish scientist is a stub . You can help Wikipedia by expanding it .
This biographical article relating to a computer scientist is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jorma_Rissanen |
Josias Eduard de Villiers (nicknamed Jos, Koelenhof; 27 December 1843 – 16 August 1898) was a Cape Colony and South African Republic surveyor, politician, and amateur astronomer. He surveyed the first neighborhood in Johannesburg , Randjeslaagte. He predicted that Johannesburg would become a city rather than disappearing like other ghost towns (as most South African civil servants of the era did), and De Villiers Street there is named after him.
From Stellenbosch , De Villiers was the second son of Jacob Isaac de Villiers by his first wife, Ester Elisabeth Johanna Hoffman. De Villiers grew up on Koelenhof farm and later in Stellenbosch, studying at the South African College and becoming a surveyor . In 1863, he was still in Cape Colony working as a surveyor, but shortly afterward left for the Orange Free State . In 1865, he was tasked with surveying the farms in Ladybrand , part of the so-called "Conquered Area" from the Free State-Basotho Wars . He settled in Boshof and represented the area from 1875 to 1882 in the Volksraad (Parliament) of the Free State. After the resolution of the long-running diamond fields dispute of the 1870s stemming from Sir Henry Barkly declaring the entire area British territory, the Free State appointed De Villiers to define its boundary with Griqualand West .
By the time gold was discovered in the Witwatersrand , De Villiers had settled in the area. Sir Joseph Robinson, 1st Baronet surveyed mining claims on Langlaagte Farm where gold would first be found, and he also inspected the 600 plots that made up the spoil tip Randjeslaagte, the seed of Johannesburg, with the help of W.H.A. Pritchard between 19 October and 3 November 1886. The streets ran north to south and east to west artificially, with no regard to terrain, and were quite broad, countering the Transvaal government's expectation of a mere mining hamlet similar to Barberton or Pilgrim's Rest . His goal was to offer as many housing plots as possible to save money, while selling the corners as valuable business offices.
The massive influx of prospective miners as well as the first merchants led the city to contract with De Villiers for expansion from 600 to 986 plots. To this end, in April 1887, the two parts of Randjeslaagte were thus connected. At the time, the claims were not proving lucrative, and the Ford and Jeppe syndicate paying for the surveys was under pressure from residents to reduce mining activity. De Villier's street plan continued from southern Marshalltown , but at the end of Bree Street some streets remained unjoined in the "nod," but the plan was never to connect Randjeslaagte together. His plots continued west to Ferreirasdorp , but to the east the owners of plots in Randjeslaagte began auctioning off land on 8 June 1887 that would become the city's first upscale suburb, Doornfontein .
In 1895, De Villiers sold his property in Johannesburg to move to Cape Town and devote himself full-time to his hobby of astronomy . In August 1896, he joined an expedition to the island of Vadsøya in Norway to view an eclipse , using his surveying skills to set up their equipment. Two years later, he was one of 16 killed in a train crash in Mostert's Hoek coming back home from Vryburg , where he had been campaigning for the Parliament of the Cape of Good Hope as a candidate for the Afrikaner Bond . At the time of his death, he was working on building an elaborate observatory at his house, Ambleside, in Sea Point .
De Villiers and his wife Christina Maria Elizabeth de Vos had three sons. | https://en.wikipedia.org/wiki/Jos_de_Villiers |
Josef Benedikt Kuriger [ 1 ] (May 25, 1754 in Einsiedeln , Schwyz – July 6, 1819 in Wettingen) [ 2 ] was a Swiss goldsmith, sculptor, modeller and model maker who pioneered embryological modeling .
Josef Benedikt Kuriger was the son of goldsmith Augustin Mathias Kuriger (1723–1780), [ 3 ] and the younger brother of the goldsmith and wax sculptor Josef Anton Kuriger (1750–1830). In c. 1768, Joseph Benedikt followed his brother Joseph Anton to Paris. There he was taught by the sculptor Étienne-Pierre-Adrien Gois . [ 4 ] Some sources say that he was first taught by Jean-Baptiste Lemoyne . [ 5 ]
Kuriger's work at the anatomical theatre in Paris gave him the experience to move from portraits and devotional objects to anatomy and obstetrics. [ 6 ] Kuriger created wax models of embryos, based on Samuel Thomas von Soemmerring 's Icones embryonum humanorum her . [ 7 ] In c. 1778, he returned to Einsiedeln and settled there, only occasionally returning to Paris.
The William Tell monument behind the St. Peter and Paul Church in Bürglen (since 1891) was created by Josef Benedikt Curiger in 1786.
Among Joseph-Benoist Couriger's works that have survived are also his anatomical models of the human body [ 8 ] (now in the Vesalianum [ fr ] in Basel). They were shown at the art exhibition in Bern in 1804 and were recently studied by Adrian Christoph Suter [ 9 ] There are more anatomical models by him in the Narrenturm museum (Vienna). [ 10 ]
In addition, there is the bust of Beaumarchais at the Comédie-Française , signed "Couriger fecit anno 1774", and all the more precious for being the only authentic contemporary bust of the author of Beaumarchais. [ 11 ] Some of his works are difficult to trace. The Schweizerisches künstler-lexikon mentions two marble bust portraits made from nature (of Captain von Hertenstein [ 12 ] and Lieutenant von Reding [ 13 ] ); "portraits in relief from white and coloured wax, alabaster and fine clay, as well as bas-reliefs, floral pieces and other works of unsurpassable truth and delicacy" and, "In the Einsiedeln cabinet", the portraits of Napoleon I, Marie Louise and the King of Rome , which he painted [modelled, in fact] in Paris in 1811 [or 1810]. [ 14 ] "Archives alsaciennes" mentions the terracotta bust of a young officer signed and dated 1773 in the Musée des Arts Décoratifs de Paris (Given by Charles-Jules Maciet, 1846–1911. It could be the "Terracotta bust of a man in court costume with long hair tied back" (Couriguer, 1773) displayed at the "Marie-Antoinette and her time" exhibition at the galerie Sedelmeyer in 1894. [ 15 ] The Musée des Arts Décoratifs has a terracotta bust matching this description (10773), and also has a terracotta-coloured wax medallion, which is not attributed but could be by Joseph-Anton (or Antoine) Couriguer. [ 16 ] "Archives alsaciennes" also mentions a male bust in the Martin Le Roy Collection. According to the Catalogue raisonné de la collection Martin Le Roy [ 17 ] this is a bust of the actor Molé [ fr ] , but the attribution to Couriguer is only a hypothesis.
The Swiss National Museum has a photo of "Terrakotten von Kuriger" taken at the 1883 National Exhibition LM-75910.91. [ 18 ] The museum also houses a painted terracotta figure of Mary with the child (1790–1800) from the church in Lauerz .
The Fram Museum in Einsielden owns four slate moulds made by Joseph-Benoist. They were used to make tin religious articles such as monstrances, candlesticks, crosses, flower stands, and holy figures for home altars and used by children to play "Pfärrerlis," a game in which they reenacted church services. [ 19 ]
Josef Benedikt Kuriger's sons were also artists, the first (and best known) one being Ildefons Kuriger (Einsiedeln 1782–1841 Vienna), sculptor and painter, modeller, draughtsman.
Augustin Mathias Kuriger (Einsiedeln 15.12.1787-Paris 01.10.1811) and Franz Xaver Kuriger (Einsiedeln 13.02.1790-Paris 02.10.1811), also wax sculptors in Paris, died there in 1811 under unexplained circumstances. The Schweizerisches Künstler-Lexikon says that "one of them was said to have murdered the other; according to another report, they were eliminated due to artistic jealousy." [ 20 ] Both were trained by Étienne-Pierre-Adrien Gois . They also seem to have trained as goldsmiths under "Rontiers" (who may be Alexandre Roëttiers de Montaleau [ fr ] , goldsmith and et medalist, who died relatively young in 1808). Their younger brothers Nikolaus Adelrich Kuriger (Einsiedeln 1797–1820 Paris) and Josef Benedikt Kuriger (Einsiedeln 1798–1816?) were also wax sculptors. [ 21 ]
Ildefons Curiger (Kuriger), wax modeller, etcher, draughtsman, painter and sculptor, was born in Einsiedeln 1732 and died around 1834 in Vienna. The Schweizerisches Künstler-Lexikon says he was the eldest and most talented of Joseph Benedikt Curiger's sons, from whom he received his first lessons in drawing and wax modelling. The works of his uncle Joseph Anton Couriguier. stimulated his innate artistic instinct even more. He made wax portraits (The Swiss National Museum owns a wax portrait (LM-70643) attributed to Ildefons, "Portrait of a lady", probably made in Einsiedeln c. 1830), bas-reliefs, etc. in coloured wax with extraordinary skill and kindness in a witty and lively manner. The authors mysteriously add that "He also made hundreds of artistic pranks." [ 22 ] He first worked in Zurich until he acquired the travel money to go to Vienna, where he attended the academy; then in Einsiedeln until about 1833, later returning to Vienna, where he is said to have died in the invalids' hospital. The Einsiedeln monastery owns the following paintings by him: St. Emilian ; [ 23 ] Peter Nolasco ; The Martyrdom of St. Ignatius , [ 24 ] St. Johann Baptist preaching ; the sketches for the altarpieces in Galgenen ; in terracotta : Christmas ; [ 25 ] The Last Supper ; The Washing of the Feet ; The Coronation after Titian; The Carrying of the Cross ; The Holy Family ; Three Kings and many smaller works; in wax: Constantine before the Apparition of the Cross. He is praised for his fruitful and genuinely artistic invention. His portrait, painted by Heinrich Corrodi [ 26 ] in 1803, in the abbey's picture cabinet, shows a brilliant artist's head.
Josef Benedikt Kuriger's brother was Joseph Anton Couriguier (born 6 June 1750 in Einsiedeln, died 1830 in Paris), who was a modeller and wax portraitist, the first son of goldsmith Augustin Mathias Kuriger. His father wanted him to become a goldsmith and trained him in drawing and modelling. He was recommended at age 17 by Johann Karl von Hedlinger [ de ] [ 27 ] to Joseph-Charles Roettiers , the royal goldsmith and medallist in Paris, where Couriguier trained for four years. Couriguier returned briefly to Switzerland in 1772 before traveling through Corsica and Toulon, ultimately settling in Paris in 1784. The Schweizerisches künstler-lexikon says he was renowned for his skill in wax portraiture, quickly gained recognition after completing a wax portrait of the Duke of Orleans (c. 1768) and later created a highly praised likeness of the first consul Bonaparte. Couriguier was known for capturing his subjects with ease, often while they dined or played games. The portrait of the Duke of Orleans may be the one that inspired Franz Gabriel Fiesinger when he engraved a portrait (or several portraits) of " Louis Philippe II, Duke of Orléans , "d'après le Modèle en cire fait par Mr Couriguer, 1789" (after the wax model made by Mr Couriguer) [ 28 ] Lami mentions a portrait of Bonaparte (an VIII, or end of 1799 and 1800). Archives alsaciennes mentions it as a "wax portrait of Napoléon, Premier Consul", and adds a portrait of him as Emperor (1804 or later). [ 29 ] Joseph Anton Couriguier also made a multicolored wax portrait depicting Lancelot Turpin de Crissé [ fr ] sitting at a table, c.1785 (the military man, not his painter son and grandson). [ 30 ]
The Swiss National Museum owns a coloured wax portrait of a gentleman in profile attributed to Joseph Anton (LM-70641), c. 1810, probably made in Einsiedeln : it could just as well be by Joseph-Benoist). He also made a wax portrait of the opera singer Pierre-Jean Garat , c. 1795 [ 31 ] Notable works in Switzerland also include a few religious sculptures. [ 32 ]
A "citizen Courigner" (Joseph Anton, no doubt) had an advertisement published in Le Moniteur Universel on 29 August 1793: [ 33 ] " I would ask you to announce in your paper that Citizen Courigner, who modelled in bas relief the portrait of Marie-Anne-Charlotte Corday , the only portrait made from life, has also just modelled that of Marat , the People's friend. – His home is rue de l'ancienne Comédie Française, no. 304, near the Bussy crossroads." [ 34 ] He published another advertisement in the same paper on 9 November 1801 : "Citizen Couriguer, sculptor, author of the portrait of the first consul, made according to nature and in medallions, both coloured natural and in different costumes, as well as in bronze, white and terracotta, has the honour of informing the public that he had previously specially entrusted citizen Talochon with the delivery; but that from this day on, it will also be possible to obtain them at his residence, Cour du Commerce, fauxbourg Saint-Germain, n° 19. He is going to produce some incessantly reduced to the point of being able to be set on rings and pins, and he warns that he has not made and will not cast any plaster." [ 35 ] This is confirmed by Nouveaux mélanges d'archéologie : "However, I saw him again in 1820, with his hair all white, but still wielding his fine ébauchoirs, which knew how to execute charming portraits that were sometimes smaller than a fingernail." [ 36 ]
Joseph Anton Couriguier was also a medalist. The Musée Carnavalet has two medals by him, one of Henri Irminger, vainqueur de la Bastille [ fr ] , 1794 [ 37 ] and the other one for the birth of duc de Bordeaux on September 29, 1820 (a collaboration with Jean-Charles Cahier, 1772–1857, goldsmith). [ 38 ] The National Portrait Gallery, London houses a wax portrait of John Nash by Joseph Anton Couriguer, c.1820–1825 (NPG 2778). [ 39 ] He executed the reverse side of the medal commemorating the death of Sir John Moore at Corunna, 1809 for James Mudie's Series of National Medals. [ 40 ] "Archives alsaciennes" as well as Stanislas Lami also attribute to Joseph-Anton a small bronze medallion of Mme Roland (Cabinet des Estampes, untraced). | https://en.wikipedia.org/wiki/Josef_Benedikt_Kuriger |
Dr. Joseph Fried (July 21, 1914 – August 17, 2001) was a Polish-American organic chemist, member of the National Academy of Sciences and the American Academy of Arts and Sciences . [ 1 ] He held 200 patents on chemical compounds, with 43 listing him as the sole holder. [ 1 ] He was a professor of chemistry and biochemistry at the University of Chicago . [ 2 ] Fried discovered fluorohydrocortisone, a chemical used to treat adrenal disorders. [ 2 ] He was also director of the organic chemistry at the Squibb Institute. [ 1 ] His discoveries were instrumental to the creation of medications to treat inflammatory disorders including as arthritis , psoriasis , and various skin allergies. [ 1 ] National Academies Press called him "an outstanding organic chemist who made very special contributions to the field of medicine". [ 3 ] Professor Elias James Corey (Nobel laureate, 1990) had this to say of Fried: "He was an outstanding, highly creative scientist who straddled both the worlds of pharmaceutical research and academic science. He was one of my heroes, and I've always thought of him as a model scientist of great character and great human warmth." [ 3 ]
Fried became a member of the National Academy of Sciences in 1971. [ 3 ] He became a member of the American Academy of Arts and Sciences in 1981. [ 3 ] He received the Medicinal Chemistry Award in 1974 from the American Chemical Society . [ 3 ] He also received the Alfred Burger Award in Medicinal Chemistry in 1996. [ 3 ] He also received the Gregory Pincus Medal from the Worcester Foundation for Experimental Biology and the Roussel Prize from the Roussel Scientific Institute in Paris in 1994. [ 3 ] Bristol-Myers Squibb and the University of Chicago launched in 1990 the first of a series of annual Josef Fried Symposia of Bioorganic Chemistry. [ 3 ] Fried is a member of the Medicinal Chemistry Hall of Fame. [ 4 ]
Josef Fried was born in the town of Przemyśl , Poland , on July 21, 1914. [ 3 ] Fried received his Ph.D. in organic chemistry from Columbia University in 1940. [ 1 ] Fried joined the Squibb Institute in 1944 as a head of its antibiotics and steroids department. He was later promoted to director of the organic chemistry section in 1959. [ 1 ] In 1963 Fried was appointed professor at the Ben May Laboratory for Cancer Research at the University of Chicago. [ 2 ] | https://en.wikipedia.org/wiki/Josef_Fried |
Josef Paldus , FRSC (November 25, 1935 – January 15, 2023) was a Czech-born Canadian theoretical chemist who was a Distinguished Professor Emeritus of Applied Mathematics at the University of Waterloo , Ontario , Canada.
Paldus became associate professor at the University of Waterloo after emigration to Canada from (former) Czechoslovakia in 1968. In 1975 he was promoted to full professor at this university, and he retired in 2001.
Paldus' research was mainly in the field of quantum chemistry and especially in the mathematical aspects of it. He is known for his collaborative work with Jiří Čížek on coupled cluster theory. [ 1 ] Paldus and Čížek adapted the many-body coupled cluster method to many-electron systems, thus making it a viable method in the study of the electronic correlation that occurs in atoms and molecules.
Other well-known work by Paldus is the Unitary Group Approach . [ 2 ] This approach regards the computation of Hamiltonian matrix elements over N -electron spin eigenstates that appear in electronic correlation problems.
Paldus (co)authored over 330 scientific papers.
Paldus possessed several doctoral degrees: In 1961 he received a PhD in Physical Chemistry at the Czechoslovak Academy of Sciences. In 1995 he became DrSc at the Charles University in Prague. In June 2006 he became Dr.h.c. at the Comenius University in Bratislava and in June 2008 he was awarded the honorary degree Docteur Honoris Causa by the Université Louis Pasteur in Strasbourg, France.
Paldus died in Kitchener on January 15, 2023, at the age of 87. [ 3 ]
Other honors received by Paldus are inter alia : | https://en.wikipedia.org/wiki/Josef_Paldus |
Joseph Achille Le Bel (21 January 1847 in Pechelbronn – 6 August 1930, in Paris, France ) was a French chemist . He is best known for his work in stereochemistry . Le Bel was educated at the École Polytechnique in Paris . In 1874 he announced his theory outlining the relationship between molecular structure and optical activity. [ 1 ] This discovery laid the foundation of the science of stereochemistry, which deals with the spatial arrangement of atoms in molecules. This hypothesis was put forward in the same year by the Dutch physical chemist Jacobus Henricus van 't Hoff and is currently known as Le Bel–van't Hoff rule . Le Bel wrote Cosmologie Rationelle (Rational Cosmology) in 1929.
This article about a French chemist is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Joseph_Achille_Le_Bel |
Joseph Black (16 April 1728 – 6 December 1799) was a British physicist and chemist, known for his discoveries of magnesium , latent heat , specific heat , and carbon dioxide . He was Professor of Anatomy and Chemistry at the University of Glasgow for 10 years from 1756, and then Professor of Medicine and Chemistry at the University of Edinburgh from 1766, teaching and lecturing there for more than 30 years. [ 1 ]
The chemistry buildings at both the University of Edinburgh and the University of Glasgow are named after Black.
Black was born "on the banks of the river Garonne " in Bordeaux , France, the sixth of the 12 children of Margaret Gordon ( d . 1747) and John Black. His mother was from an Aberdeenshire family that had connections with the wine business and his father was from Belfast , Ireland, and worked as a factor in the wine trade . [ 2 ] He was educated at home until the age of 12, after which he attended grammar school in Belfast. In 1746, at the age of 18, he entered the University of Glasgow , studying there for four years before spending another four at the University of Edinburgh , furthering his medical studies. During his studies he wrote a doctorate thesis on the treatment of kidney stones with the salt magnesium carbonate . [ 3 ]
Like most 18th-century experimentalists, Black's conceptualisation of chemistry was based on five principles of matter: Water, Salt, Earth, Fire and Metal. [ 4 ] He added the principle of Air when his experiments showed the presence of carbon dioxide , which he called fixed air , thus contributing to pneumatic chemistry .
Black's research was guided by questions relating to how the principles combined with each other in various different forms and mixtures. He used the term affinity to describe the force that held such combinations together. [ 5 ] Throughout his career he used a variety of diagrams and formulas to teach his University of Edinburgh students how to manipulate affinity through different kinds of experimentation. [ 6 ]
In about 1750, while still a student, Black developed the analytical balance based on a light-weight beam balanced on a wedge-shaped fulcrum . Each arm carried a pan on which the sample or standard weights was placed. It far exceeded the accuracy of any other balance of the time and became an important scientific instrument in most chemistry laboratories. [ 7 ]
Black also explored the properties of a gas produced in various reactions. He found that limestone ( calcium carbonate ) could be heated or treated with acids to yield a gas he called "fixed air." He observed that the fixed air was denser than air and did not support either flame or animal life. Black also found that when bubbled through an aqueous solution of lime ( calcium hydroxide ), it would precipitate calcium carbonate. He used this phenomenon to illustrate that carbon dioxide is produced by animal respiration and microbial fermentation .
In 1757, Black was appointed Regius Professor of the Practice of Medicine at the University of Glasgow . In 1756 or soon thereafter, he began an extensive study of heat. [ 8 ]
In 1760 Black realized that when two different substances of equal mass but different temperatures are mixed, the changes in number of degrees in the two substances differ, though the heat gained by the cooler substance and lost by the hotter is the same. Black related an experiment conducted by Daniel Gabriel Fahrenheit on behalf of Dutch physician Herman Boerhaave . For clarity, he then described a hypothetical, but realistic variant of the experiment: If equal masses of 100 °F water and 150 °F mercury are mixed, the water temperature increases by 20 ° and the mercury temperature decreases by 30 ° (to 120 °F), though the heat gained by the water and lost by the mercury is the same. This clarified the distinction between heat and temperature. It also introduced the concept of specific heat capacity, being different for different substances. Black wrote: “Quicksilver [mercury] ... has less capacity for the matter of heat than water.” [ 9 ] [ 10 ]
In 1761, Black deduced that the application of heat to ice at its melting point does not cause a rise in temperature of the ice/water mixture, but rather an increase in the amount of water in the mixture. Additionally, Black observed that the application of heat to boiling water does not result in a rise in temperature of a water/steam mixture, but rather an increase in the amount of steam. From these observations, he concluded that the heat applied must have combined with the ice particles and boiling water and become latent. [ 11 ]
The theory of latent heat marks the beginning of thermodynamics . [ 12 ] Black's theory of latent heat was one of his more-important scientific contributions, and one on which his scientific fame chiefly rests. He also showed that different substances have different specific heats .
The theory ultimately proved important not only in the development of abstract science but in the development of the steam engine . [ 13 ] Black and James Watt became friends after meeting around 1757 while both were at Glasgow . Black provided significant financing and other support for Watt's early research in steam power. Black's discovery of the latent heat of water would have been interesting to Watt, [ 14 ] informing his attempts to improve the efficiency of the steam engine invented by Thomas Newcomen and develop the science of thermodynamics.
In 1766, treading in the footsteps of his friend and former teacher at the University of Glasgow, Black succeeded William Cullen as Professor of Medicine and Chemistry at the University of Edinburgh (Cullen had moved to Edinburgh in 1755). His position at Glasgow University was filled by Alexander Stevenson . [ 15 ]
At this point he gave up research and devoted himself exclusively to teaching. In this he was successful with audience attendance at his lectures increasing from year to year for more than thirty years. His lectures had a powerful effect in popularising chemistry and attendance at them even came to be a fashionable amusement.
Black was widely recognised as one of the most popular lecturers at the University. His chemistry course regularly attracted an exceptionally high number of students, with many attending two or three times. In addition to regularly introducing cutting-edge topics and meticulously selecting visually impressive experiments, Black employed a wide array of successful teaching tools that made chemistry accessible to his students (many of whom were as young as 14 years old). [ 16 ] [ 17 ] His students came from across the United Kingdom, its colonies and Europe, and hundreds of them preserved his lectures in their notebooks and disseminated his ideas after they left university.
He became one of the principal ornaments of the University; and his lectures were attended by an audience which continued increasing from year to year, for more than thirty years. It could not be otherwise. His personal appearance and manners were those of a gentleman, and peculiarly pleasing. His voice in lecturing was low, but fine; and his articulation so distinct, that he was perfectly well heard by an audience consisting of several hundreds. His discourse was so plain and perspicuous, his illustration by experiment so apposite, that his sentiments on any subject never could be mistaken even by the most illiterate; and his instructions were so clear of all hypothesis or conjecture, that the hearer rested on his conclusions with a confidence scarcely exceeded in matters of his own experience. [ 18 ]
On 17 November 1783 he became one of the founders of the Royal Society of Edinburgh . [ 19 ] From 1788 to 1790 he was President of the Royal College of Physicians of Edinburgh . [ 20 ] He was a member of the revision committee for the editions of the college's Pharmacopoeia Edinburgensis of 1774, 1783, and 1794. Black was appointed principal physician to King George III in Scotland.
Black's research and teaching were reduced as a result of poor health. From 1793 his health declined further and he gradually withdrew from his teaching duties. In 1795, Charles Hope was appointed his coadjutor in his professorship, and in 1797, he lectured for the last time.
Black was a member of The Poker Club . He was 1st cousin, great friend and colleague to Adam Ferguson FRSE who married his niece Katherine Burnett in 1767, and associated with David Hume , Adam Smith , and the literati of the Scottish Enlightenment . He was also close to pioneering geologist James Hutton . [ 21 ]
In 1773 he is listed as living on College Wynd on the south side of the Old Town . [ 22 ] In the 1790s, he used Sylvan House in Sciennes as a summer retreat. A plaque, unveiled in 1991, commemorates his occupancy of the house. [ 23 ]
Black never married. He died peacefully at his home 12 Nicolson Street [ 24 ] in south Edinburgh in 1799 at the age of 71 and is buried in Greyfriars Kirkyard . The large monument lies in the sealed section to the south-west known as the Covenanter's Prison.
In 2011, scientific equipment believed to belong to Black was discovered during an archaeological dig at the University of Edinburgh. [ 25 ] | https://en.wikipedia.org/wiki/Joseph_Black |
Joseph Gilbert Hamilton (November 11, 1907 – February 18, 1957) was an American professor of Medical Physics, Experimental Medicine, General Medicine, and Experimental Radiology as well as director (1948–1957) of the Crocker Laboratory, part of the Lawrence Berkeley National Laboratory . Hamilton studied the medical effects of exposure to radioactive isotopes , which included the use of unsuspecting human subjects .
He was married to painter Leah Rinne Hamilton. [ 1 ] [ 2 ]
Hamilton received his B.S. in Chemistry in 1929 from the University of California . He studied medicine in Berkeley and interned at the University of California Hospital, San Francisco. He was awarded his M.D. degree in 1936. At that time the cyclotron in Berkeley was among the first to produce useful amounts of radioactive isotopes which could be used in studies of their effects on living tissue. In a series of papers published in 1937 Hamilton detailed early medical trials using radioactive sodium, followed by papers detailing the use of the radioactive isotopes of potassium, chlorine, bromine, and iodine. [ 3 ] Radioactive iodine was found to be particularly useful in the diagnosis and treatment of thyroid disorders.
Concern was expressed over the safety of Manhattan Project laboratory personnel working with newly isolated plutonium in 1944. Hamilton led a team to conduct toxicity experiments on rats. Finding the results unsatisfactory, Hamilton participated in the decision to continue the trials with human subjects. The teams conducted trials in secret from 1945 to 1947. [ 4 ]
Three teams headed by Hamilton, Louis Hempelmann and Wright Haskell Langham carried out trials, injecting plutonium into 18 unsuspecting human patients and measuring its concentration in excreta. Joseph Gilbert Hamilton's team injected three of the subjects at University of California Hospital, San Francisco .
Albert Stevens , CAL-1, was diagnosed with terminal stomach cancer, which researchers soon found to have been an ulcer. Stevens is significant as he is recorded to have survived the highest known accumulated radiation dose of any human. He lived 20 years after the injection and died at 79 years of age. [ 4 ]
Simeon Shaw, CAL-2, was 4 years old at the time of injection and diagnosed with bone cancer. Shaw lived for 255 days post injection, with his cause of death being recorded as bone cancer. [ 4 ]
Elmer Allen, CAL-3, was 36 at the time of injection and lived for 44 years post injection, with his cause of death being recorded as respiratory failure, pneumonia. [ 4 ] He died in 1991 shortly before Eileen Welsome could interview him for her work in exposing the trials. [ 5 ]
Hamilton's studies of isotope retention in humans, especially of radioactive strontium and the transuranic elements, were the principal reason for the U.S. Atomic Energy Commission setting of far lower tolerance limits of these substances than had been theorised before trials. [ 4 ] The Atomic Energy Commission terminated this series of human trials in 1950.
Once the AEC took over control of the Manhattan Project's various roles, Hamilton returned to his work at Berkeley. In a memo written in 1950, Hamilton gave some recommendations to the AEC's Director of Biology and Medicine, Shields Warren . Hamilton wrote that large primates like "chimpanzees ... [should] be substituted for humans in the planned studies on radiation's cognitive effects." [ 6 ] He further warned that by using humans the AEC would be open "to considerable criticism," since the experiments as proposed had "a little of the Buchenwald touch." [ 6 ] Eugene Saenger would be the one who carried out these experiments from 1960 to 1971 at the University of Cincinnati , exposing "at least 90 cancer patients to large radiation doses." [ 7 ] [ 8 ]
Hamilton died from leukemia at the age of 49. [ 3 ] His name was added to the Monument to the X-ray and Radium Martyrs of All Nations erected in Hamburg , Germany. | https://en.wikipedia.org/wiki/Joseph_Gilbert_Hamilton |
Joseph Simon Glickauf Jr. (January 15, 1912 – July 9, 2005), was an American-born engineer, inventor and corporate executive known as one of the first advocates of the use of computers in business and industry and the "father" of the computer consulting industry. [ 1 ]
Glickauf graduated from Hyde Park High School in Chicago and attended Illinois Institute of Technology . He joined the United States Navy in 1942 and was assigned to the Research Division of the Bureau of Supplies and Accounts . He became a lieutenant. After leaving the navy, he was hired by Arthur Andersen Co. immediately in 1946 and was tasked with initiating the use of the freshly invented computer for his employer. Glickauf became familiar with the capabilities of the UNIVAC (Universal Automatic Computer) and immediately saw the far-reaching implications of computers for business. To demonstrate the computer to Arthur Andersen’s employees he built the Arthur Andersen Demonstration Computer known as "Glickiac". The company management was quick to see the potential and made resources available for future development.
In 1953 General Electric Appliances hired Arthur Andersen to automate GE's payroll. Glickauf lead the effort and recommended GE the installation of a UNIVAC I computer and printer. The project was initially a failure but it started what is now known as "computer consulting". [ 1 ]
He is buried at Plum Lake Cemetery, Sayner, Wisconsin. | https://en.wikipedia.org/wiki/Joseph_Glickauf |
Joseph H. Burckhalter was a chemist who worked in the field of isothiocyanate compounds. In 1995 he was inducted into the National Inventors Hall of Fame alongside Robert Seiwald . [ 1 ] Burckhalter is also a member of the Medicinal Chemistry Hall of Fame. [ 2 ]
Burckhalter earned a B.S. in chemistry from the University of South Carolina in 1934 and an M.S. in organic chemistry from the University of Illinois, Urbana , in 1938. In 1942, he received his doctorate in medicinal chemistry at the University of Michigan , where he had been a graduate student of Frederick Blicke. [ 3 ] | https://en.wikipedia.org/wiki/Joseph_H._Burckhalter |
Joseph Jonah Rotman (May 26, 1934 – October 16, 2016 [ 1 ] ) was a Professor of Mathematics at the University of Illinois at Urbana–Champaign [ 2 ] and also a published author of 10 textbooks.
Rotman was born in Chicago . He did his undergraduate and graduate work at the University of Chicago , where he received his doctorate in 1959 with a thesis in abelian groups written under the direction of Irving Kaplansky . [ 3 ] In 1959 he moved to the University of Illinois at Urbana–Champaign, where he spent the rest of his mathematical career. Rotman retired from UIUC in 2004. [ 4 ] His research interests lay in the area of algebra , involving abelian groups , modules , homological algebra , and combinatorics . [ 5 ]
Rotman was the Managing Editor of the Proceedings of the American Mathematical Society in 1972–1973. [ 4 ] In 1985 he was the Annual Visiting Lecturer of the South African Mathematical Society . [ 6 ]
A partial list of Rotman's publications includes:
This article about an American mathematician is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Joseph_J._Rotman |
Joseph Joshua Weiss (30 August 1905 – 9 April 1972) [ 1 ] was a Jewish-Austrian [ 2 ] chemist and Professor at the Newcastle University . He was a pioneer in the field of radiation chemistry and photochemistry .
Weiss was born in 1905 in Austria . He had obtained a Dipl.Ing. degree in the Technische Hochschule in Vienna . He entered the Textile Institute at Sorau in 1928 and was the head of the chemistry department there. He left his post two years later to become an assistant to the German chemist Fritz Haber at the Kaiser Wilhelm Institute for Physical Chemistry and Elektrochemistry in Berlin. Together they discovered the Haber–Weiss reaction . He fled with Haber (who was born Jewish) from Nazi Germany to Cambridge in 1933. He later moved to University College London , where he got his PhD in 1935 from Prof Frederick George Donnan . [ 3 ] in 1937 he started teaching at the King's College in Durham, which later became Newcastle University . In the thirties, Weiss published several of his ideas on electron transfer processes in the mechanisms of thermal and photochemical reactions in solution.
In 1956, he was appointed a professor of Radiation Chemistry at Newcastle University .
In 1968, he received an honorary degree from Technische Universität Berlin . In 1970 he received the Marie Curie Medal from the Curie Institute , and officially retired from his chair at Newcastle. In 1972 the Association for Radiation Research established the Weiss Medal , named after him.
In 1942, Weiss married Frances Sonia Lawson, whom he would go on to have two sons and a daughter with. | https://en.wikipedia.org/wiki/Joseph_Joshua_Weiss |
Franz Joseph König (15 November 1843 – 12 April 1930) was a German chemist noted among other things as the founder of German food chemistry . He developed many analytical techniques and created the foundations for the modern quality control of foodstuffs.
König was born in Lavesum, Haltern , North Rhine-Westphalia . He studied at the Georg-August-Universität Göttingen and was a member of the Corps Verdensia (1866) and Hercynia (1922). [ 1 ] [ 2 ] He was awarded a D.Phil.
In 1871 he became director of the newly established agricultural research station in Münster . In 1892 he was elected honorary professor at the Münster Royal Academy ( Königliche Akademie zu Münster ) and in 1899 was appointed to a chair at the present Westfälische Wilhelms-Universität . In 1887 he was elected a member of the Leopoldina .
He was appointed a Geheimer Regierungsrat .
König died on 12 April 1930 in Münster. | https://en.wikipedia.org/wiki/Joseph_König_(chemist) |
Joseph Howard McLain (July 11, 1916 – July 26, 1981) was an American chemist. He was a professor at Washington College and became college president. He is best known for his expertise in solid state chemistry and pyrotechnics . He held 30 patents, including for smoke grenades, underwater torches, and flares. [ 1 ]
Joseph McLain was born in Weirton, West Virginia on July 11, 1916, the son of Howard and Elizabeth McLain. [ 2 ] He spent his childhood in Baltimore, Maryland . [ 3 ] Like his older brother, McLain was educated at Washington College . [ 4 ] While in college, McLain was a member of Theta Chi , president of the class of 1937, and played basketball, football, lacrosse, and track. [ 5 ] [ 1 ] He did his doctoral work at Johns Hopkins University in chemistry. During World War II, McLain paused his education to serve as a major in the US Army Chemical Corps doing research on smoke screens and pyrotechnics. [ 4 ] [ 6 ]
Joseph McLain received his doctorate in 1946 and joined the faculty of Washington College the same year. While he was a professor, McLain was a partner in the Kent Manufacturing Company, which made fireworks, until there was an explosion at the plant in 1954. [ 6 ] During the explosion, McLain rescued two women from the plant. [ 4 ] After the disaster, McLain and his partners dissolved the company and McLain and worked on safety standards for fireworks with fellow Washington College alumnus and professor John Conkling . [ 6 ] [ 7 ] The pair wrote recommendations for the safe storage for fireworks that became part of the first US standards. [ 7 ] In addition to his pyrotechnic research, McLain was active in environmental work, serving as a trustee of the Chesapeake Bay Foundation and sitting on Maryland Water Pollution Control Commission. [ 1 ] In 1973, McLain became the president of Washington College . [ 3 ] He is the only alumnus of the school to ever serve as president. [ 8 ] [ 9 ] McLain took a leave of absence from the college in 1981 and died in Baltimore at Johns Hopkins Hospital the same year. [ 1 ] [ 4 ]
Joseph McLain was married to Margret Anne Hollingsworth McLain. [ 4 ] | https://en.wikipedia.org/wiki/Joseph_McLain |
Joseph Melia is a philosopher working in the areas of philosophy of mathematics , modal logic and possible worlds . He has made important contributions to the debate over the Quine–Putnam indispensability argument , where he argues for a "weaseling" approach to mathematical nominalism . [ 1 ] [ 2 ] [ 3 ] He has also argued against modalism and the modal realism of David Lewis . [ 4 ] [ 5 ]
This biography of a British philosopher is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Joseph_Melia |
Joseph Patrick Slattery , CM (21 May 1866 – 31 March 1931) was an Irish-born physicist, radiologist, Catholic priest, pioneer in the field of radiography in Australia and credited with the first use of fluoroscopy in Australia.
Born in 1866 in Waterford, Ireland , he traveled to Australia as a deacon in 1888, where he was ordained a priest by Cardinal Moran. As a member of the Vincentian Congregation, he and several of his confreres took over the running of St Stanislaus' at Bathurst from the diocesan clergy. Appointed to the position of professor and taught science, including physics and chemistry. Slattery had a keen interest in the new technology of wireless radio and was the first to install a wireless set west of the Blue Mountains . He was an early pioneer of radio in Australia and found delight in building radio sets.
Slattery built an X-ray practice at Bathurst and local doctors benefited greatly from this convenience. He performed mission work for the Vincentian fathers and toured Australia and New Zealand to serve the faithful. Slattery was superior of the Vincentian novitiate at Eastwood . He was appointed vice-rector of St. John's College at the University of Sydney . At Springwood and Manly , he was spiritual director of the seminaries for 6 years. Slattery performed parish work for the last three years of his life.
In 1931, he died and was buried in Rookwood Cemetery at Sydney, New South Wales, Australia. [ 1 ]
Joseph Patrick Slattery was born in 1866 at Waterford , Ireland, the son of John and Hanna ( née Walsh) Slattery. He attended Waterpark College , a Christian Brothers' College (Waterford) and then St. Vincent's College, Castleknock (Dublin) from 1877 to 1886.
At St Vincent's, he fell under the tutelage of Father Richard Bodkin, CM. Father Bodkin had an excellent science laboratory that included a Callan battery from noted Irish priest, scientist and inventor Father Nicholas Callan . In 1886, Slattery achieved honours in experimental physics from his university examinations. On 7 September 1886, he entered St. Joseph's, the Vincentian seminary at Blackrock in Dublin, Ireland. [ 2 ] [ 3 ]
Slattery was offered a position as professor at St. Stanislaus' College in Bathurst , Australia. He left Dublin and arrived in Sydney on 29 November 1888. On 1 January 1889, he took over as headmaster and joined the Vincentian staff to assist with the operation of the College. He taught courses in the natural sciences , in particular chemistry and physics . [ 2 ] [ 3 ] [ 4 ] [ 5 ]
He continued ecclesiastical studies while he taught the natural sciences. Slattery began to amass scientific equipment for the school's laboratories. Much of the equipment and devices he built himself, as he was an expert glassblower . He was assisted by chemistry teacher and collaborator, C. A. Mulholland. [ 3 ] [ 4 ] [ 5 ] On 8 December 1891, Slattery was ordained as a Catholic priest by Cardinal Patrick Francis Moran in the college chapel and became prefect of studies. Until 1911, he continued to teach physics, chemistry and geology. [ 3 ] [ 5 ]
In 1893, Slattery installed gas lighting fixtures with incandescent burners into the study halls, almost one year before these became available in Australia. In 1895, the college acquired a gasoline powered engine, a six-inch (15 cm) sparking coil and two Crookes tubes . That same year the school upgraded to an oil powered engine, dynamo and storage batteries that supplied electric light to the science halls. At the time this was the only electric light in Bathurst. Next, he built an acetylene gas powered generator to provide stage lighting for the college theatre. At this time he developed an early interest in colour photography . [ 2 ] [ 6 ]
In January 1896, Slattery read in local newspapers of Wilhelm Röntgen 's breakthrough: “A new photographic discovery” and focused his pursuits on radiography . [ 7 ]
He read of events in Melbourne, Adelaide and Sydney and on 25 July 1896 he took a radiograph of the hand of 12-year-old Eric Thompson, enabling the surgeon Dr. Edmunds to extract shotgun pellets from the hand. Before viewing the X-ray, the surgeon had considered amputation of the injured hand. [ 8 ] [ 9 ] [ 10 ]
Slattery continued the radiology practice until 1911. Local doctors brought patients to his practice and word of his expertise developed. He built a thirteen-inch (33 cm) induction coil , sponsored by local individuals and this permitted shorter exposure times. He radiographed bone fractures along with splinters, metal shards and other objects embedded in the flesh. Slattery realised that the European-made focus tubes with prolonged use resulted in harder (or higher energy) X-rays as the vacua in the tubes increased. Slattery devised an improved regulator for the Crookes tubes and communicated these improvements to Röntgen, who replied with appreciation. [ 6 ]
Slattery had a keen interest in wireless telegraphy and in 1900 transmitted signals throughout the College campus. On 10 September 1900, he presented in Sydney to the Australasian Catholic Congress a paper, "The development of electrical sciences".
At Bathurst Technical College he delivered a talk on: “Electrical discharges through the air and rarefied gases”. In July 1903, St. Stanislaus College took delivery from London of wireless telegraphy equipment.
On 9 February 1904, messages were transmitted from the College and received at the Kelso Cathedral tower three miles (4.8 km) away. In 1910, he published in the College's year book ( Echoes from St Stanislaus ), a paper, "Wave motion in ether". At the outbreak of WWI in 1914, the wireless transmitter was dismantled. The wireless set that Slattery constructed has been preserved at St Stanislaus' College. [ 4 ] [ 5 ]
In 1911, Slattery was assigned to pastoral duties at St. Vincent's parish, in Ashfield , Sydney, Australia. Beginning in 1912, he preached in New South Wales and Queensland at missions and retreats. From 1920 to 1927, Slattery was spiritual director at the Springwood and Manly seminaries. He performed mission work for the Vincentian fathers and toured Australia and New Zealand to serve the faithful.
In 1923, Slattery was superior rector of St Joseph's Vincentian Novitiate at Eastwood . In September 1926, as his health was failing, he was appointed vice-rector of St. John's College at the University of Sydney . Slattery performed parish work for the last 3 years of his life. He died of heart disease on 31 March 1931, aged 64, in Lewisham Hospital and was buried in Rookwood Cemetery at Sydney . [ 1 ] [ 2 ]
Australia is one of the few countries to recognise a group of people for a major achievement where the group worked independently in different locales. To this day the accomplishments of these 3 people are disputed. Not the fact that the events occurred, but the claim of who did what first, and who should receive credit for being the first in Australia to perform medical radiography . Australia Post decided the most equitable way was to depict all three individuals on a postage stamp, issued to coincided and commemorate the 100th anniversary of Wilhelm Röntgen 's discovery of X-rays . On 7 September 1995, Walter Drowley Filmer , Sir Thomas Ranken Lyle , and Father Slattery were recognised as pioneers of X-ray technology in Australia. [ 6 ] [ 11 ] | https://en.wikipedia.org/wiki/Joseph_Patrick_Slattery |
The Joseph Weber Award for Astronomical Instrumentation is awarded by the American Astronomical Society to an individual for the design, invention or significant improvement of instrumentation leading to advances in astronomy . [ 1 ] It is named after physicist Joseph Weber . The awards tend to be for a career of instrument development rather than a single specific device; the lists of inventions below are taken from press releases from the recipients' institutions.
Source: American Astronomical Society | https://en.wikipedia.org/wiki/Joseph_Weber_Award_for_Astronomical_Instrumentation |
Joseph Henry Maclagan Wedderburn FRSE FRS (2 February 1882 – 9 October 1948) was a Scottish mathematician, who taught at Princeton University for most of his career. A significant algebraist , he proved that a finite division algebra is a field ( Wedderburn's little theorem ), and part of the Artin–Wedderburn theorem on simple algebras . He also worked on group theory and matrix algebra . [ 2 ] [ 3 ]
His younger brother was the lawyer Ernest Wedderburn .
Joseph Wedderburn was the tenth of fourteen children of Alexander Wedderburn of Pearsie, a physician, and Anne Ogilvie. He was educated at Forfar Academy then in 1895 his parents sent Joseph and his younger brother Ernest to live in Edinburgh with their paternal uncle, J. R. Maclagan Wedderburn, allowing them to attend George Watson's College . This house was at 3 Glencairn Crescent in the West End of the city. [ 4 ]
In 1898 Joseph entered the University of Edinburgh . In 1903, he published his first three papers, worked as an assistant in the Physical Laboratory of the University, obtained an MA degree with first class honours in mathematics, and was elected a Fellow of the Royal Society of Edinburgh , upon the proposal of George Chrystal , James Gordon MacGregor , Cargill Gilston Knott and William Peddie . Aged 21 on election he remains one of the youngest Fellows ever. [ 5 ]
He then studied briefly at the University of Leipzig and the University of Berlin , where he met the algebraists Frobenius and Schur . A Carnegie Scholarship allowed him to spend the 1904–1905 academic year at the University of Chicago where he worked with Oswald Veblen , E. H. Moore , and most importantly, Leonard Dickson , who was to become the most important American algebraist of his day.
Returning to Scotland in 1905, Wedderburn worked for four years at the University of Edinburgh as an assistant to George Chrystal , who supervised his D.Sc , awarded in 1908 for a thesis titled On Hypercomplex Numbers . He gained a PhD in algebra from the University of Edinburgh in 1908. [ 6 ] From 1906 to 1908, Wedderburn edited the Proceedings of the Edinburgh Mathematical Society . In 1909, he returned to the United States to become a Preceptor in Mathematics at Princeton University ; his colleagues included Luther P. Eisenhart , Oswald Veblen , Gilbert Ames Bliss , and George Birkhoff .
Upon the outbreak of the First World War , Wedderburn enlisted in the British Army as a private. He was the first person at Princeton to volunteer for that war, and had the longest war service of anyone on the staff. He served with the Seaforth Highlanders in France, as Lieutenant (1914), then as Captain of the 10th Battalion (1915–18). While a Captain in the Fourth Field Survey Battalion of the Royal Engineers in France, he devised sound-ranging equipment to locate enemy artillery.
He returned to Princeton after the war, becoming Associate Professor in 1921 and editing the Annals of Mathematics until 1928. While at Princeton, he supervised only three PhDs, one of them being Nathan Jacobson . In his later years, Wedderburn became an increasingly solitary figure and may even have suffered from depression. His isolation after his 1945 early retirement was such that his death from a heart attack was not noticed for several days. His Nachlass was destroyed, as per his instructions.
Wedderburn received the MacDougall-Brisbane Gold Medal and Prize from the Royal Society of Edinburgh in 1921, and was elected to the Royal Society of London in 1933. [ 1 ]
In all, Wedderburn published about 40 books and papers, making important advances in the theory of rings, algebras and matrix theory.
In 1905, Wedderburn published a paper that included three claimed proofs of a theorem stating that a noncommutative finite division ring could not exist. The proofs all made clever use of the interplay between the additive group of a finite division algebra A , and the multiplicative group A * = A -{0}. Parshall (1983) notes that the first of these three proofs had a gap not noticed at the time. Meanwhile, Wedderburn's Chicago colleague Dickson also found a proof of this result but, believing Wedderburn's first proof to be correct, Dickson acknowledged Wedderburn's priority. But Dickson also noted that Wedderburn constructed his second and third proofs only after having seen Dickson's proof. Parshall concludes that Dickson should be credited with the first correct proof.
This theorem yields insights into the structure of finite projective geometries . In their paper on "Non-Desarguesian and non-Pascalian geometries" in the 1907 Transactions of the American Mathematical Society , Wedderburn and Veblen showed that in these geometries, Pascal's theorem is a consequence of Desargues' theorem . They also constructed finite projective geometries which are neither "Desarguesian" nor "Pascalian" (the terminology is Hilbert 's).
Wedderburn's best-known paper was his sole-authored "On hypercomplex numbers," published in the 1907 Proceedings of the London Mathematical Society , and for which he was awarded the D.Sc. the following year. This paper gives a complete classification of simple and semisimple algebras . He then showed that every finite-dimensional semisimple algebra can be constructed as a direct sum of simple algebras and that every simple algebra is isomorphic to a matrix algebra for some division ring . The Artin–Wedderburn theorem generalises these results to algebras with the descending chain condition.
His best known book is his Lectures on Matrices (1934), [ 7 ] which Jacobson praised as follows:
That this was the result of a number of years of painstaking labour is evidenced by the bibliography of 661 items (in the revised printing) covering the period 1853 to 1936. The work is, however, not a compilation of the literature, but a synthesis that is Wedderburn's own. It contains a number of original contributions to the subject.
About Wedderburn's teaching:
He was apparently a very shy man and much preferred looking at the blackboard to looking at the students. He had the galley proofs from his book "Lectures on Matrices" pasted to cardboard for durability, and his "lecturing" consisted of reading this out loud while simultaneously copying it onto the blackboard. | https://en.wikipedia.org/wiki/Joseph_Wedderburn |
The Josephson junction count is the number of Josephson junctions on a superconducting integrated circuit chip. Josephson junctions are active circuit elements in superconducting circuits. The Josephson junction count is a measure of circuit or device complexity, similar to the transistor count used for semiconductor integrated circuits.
Examples of circuits using Josephson junctions include digital circuits based on SFQ logic (e.g., RSFQ , RQL , adiabatic quantum flux parametron), superconducting quantum computing circuits, superconducting analog circuits , etc.
The superconducting integrated circuits listed here must have been fabricated and tested, but are not required to be commercially available. Chip area includes the full extent of the chip.
Maker column may include organizations that designed and fabricated the chip.
Process column information: minimum linewidth, Josephson junction critical current density, superconducting layer number and materials.
Conversions for units of critical current density: 1 MA/m 2 = 1 μ A/μm 2 = 100 A/cm 2 .
Memory is an electronic data storage device , often used as computer memory , on a single integrated circuit chip. The superconducting integrated circuits listed here must have been fabricated and tested, but are not required to be commercially available. Chip area includes the full extent of the chip. | https://en.wikipedia.org/wiki/Josephson_junction_count |
In computer science and mathematics , the Josephus problem (or Josephus permutation ) is a theoretical problem related to a certain counting-out game . Such games are used to pick out a person from a group, e.g. eeny, meeny, miny, moe .
In the particular counting-out game that gives rise to the Josephus problem, a number of people are standing in a circle waiting to be executed. Counting begins at a specified point in the circle and proceeds around the circle in a specified direction. After a specified number of people are skipped, the next person is executed. The procedure is repeated with the remaining people, starting with the next person, going in the same direction and skipping the same number of people, until only one person remains, and is freed.
The problem—given the number of people, starting point, direction, and number to be skipped—is to choose the position in the initial circle to avoid execution.
The problem is named after Flavius Josephus , a Jewish historian and leader who lived in the 1st century. According to Josephus's firsthand account of the siege of Yodfat , he and his 40 soldiers were trapped in a cave by Roman soldiers . They chose suicide over capture, and settled on a serial method of committing suicide by drawing lots. Josephus states that by luck or possibly by the hand of God, he and another man remained until the end and surrendered to the Romans rather than killing themselves. This is the story given in Book 3, Chapter 8, part 7 of Josephus's The Jewish War ( writing of himself in the third person ):
However, in this extreme distress, he was not destitute of his usual sagacity; but trusting himself to the providence of God, he put his life into hazard [in the manner following]: "And now," said he, "since it is resolved among you that you will die, come on, let us commit our mutual deaths to determination by lot. He whom the lot falls to first, let him be killed by him that hath the second lot, and thus fortune shall make its progress through us all; nor shall any of us perish by his own right hand, for it would be unfair if, when the rest are gone, somebody should repent and save himself." This proposal appeared to them to be very just; and when he had prevailed with them to determine this matter by lots, he drew one of the lots for himself also. He who had the first lot laid his neck bare to him that had the next, as supposing that the general would die among them immediately; for they thought death, if Josephus might but die with them, was sweeter than life; yet was he with another left to the last, whether we must say it happened so by chance, or whether by the providence of God. And as he was very desirous neither to be condemned by the lot, nor, if he had been left to the last, to imbrue his right hand in the blood of his countrymen, he persuaded him to trust his fidelity to him, and to live as well as himself.
The details of the mechanism used in this feat are rather vague. According to James Dowdy and Michael Mays, [ 2 ] in 1612 Claude Gaspard Bachet de Méziriac suggested the specific mechanism of arranging the men in a circle and counting by threes to determine the order of elimination. [ 3 ] This story has been often repeated and the specific details vary considerably from source to source. For instance, Israel Nathan Herstein and Irving Kaplansky (1974) have Josephus and 39 comrades stand in a circle with every seventh man eliminated. [ 4 ] A history of the problem can be found in S. L. Zabell's Letter to the editor of the Fibonacci Quarterly . [ 5 ]
As to intentionality, Josephus asked: “shall we put it down to divine providence or just to luck?” [ 6 ] But the surviving Slavonic manuscript of Josephus tells a different story: that he “counted the numbers cunningly and so managed to deceive all the others”. [ 6 ] [ 7 ] Josephus had an accomplice; the problem was then to find the places of the two last remaining survivors (whose conspiracy would ensure their survival). It is alleged that he placed himself and the other man in the 31st and 16th place respectively (for k = 3 below). [ 8 ]
A medieval version of the Josephus problem involves 15 Turks and 15 Christians aboard a ship in a storm which will sink unless half the passengers are thrown overboard. All 30 stand in a circle and every ninth person is to be tossed into the sea. The Christians need to determine where to stand to ensure that only the Turks are tossed. [ 9 ] In other versions the roles of Turks and Christians are interchanged.
Graham, Knuth & Patashnik 1989 , p. 8 describe and study a "standard" variant: Determine where the last survivor stands if there are n people to start and every second person ( k = 2 below) is eliminated.
A generalization of this problem is as follows. It is supposed that every m th person will be executed from a group of size n , in which the p th person is the survivor. If there is an addition of x people to the circle, then the survivor is in the p + mx -th position if this is less than or equal to n + x . If x is the smallest value for which p + mx > n + x , then the survivor is in position ( p + mx ) − ( n + x ) . [ 10 ]
In the following, n {\displaystyle n} denotes the number of people in the initial circle, and k {\displaystyle k} denotes the count for each step, that is, k − 1 {\displaystyle k-1} people are skipped and the k {\displaystyle k} -th is executed. The people in the circle are numbered from 1 {\displaystyle 1} to n {\displaystyle n} , the starting position being 1 {\displaystyle 1} and the counting being inclusive .
The problem is explicitly solved when every second person will be killed (every person kills the person on their left or right), i.e. k = 2 {\displaystyle k=2} . (For the more general case k ≠ 2 {\displaystyle k\neq 2} , a solution is outlined below.)
The solution is expressed recursively . Let f ( n ) {\displaystyle f(n)} denote the position of the survivor when there are initially n people (and k = 2 {\displaystyle k=2} ).
The first time around the circle, all of the even -numbered people die.
The second time around the circle, the new 2nd person dies, then the new 4th person, etc.; it is as though there were no first time around the circle.
If the initial number of people were even, then the person in position x during the second time around the circle was originally in position 2 x − 1 {\displaystyle 2x-1} (for every choice of x ). Let n = 2 j {\displaystyle n=2j} . The person at f ( j ) {\displaystyle f(j)} who will now survive was originally in position 2 f ( j ) − 1 {\displaystyle 2f(j)-1} . This yields the recurrence
If the initial number of people were odd , then person 1 can be thought of as dying at the end of the first time around the circle. Again, during the second time around the circle, the new 2nd person dies, then the new 4th person, etc.
In this case, the person in position x was originally in position 2 x + 1 {\displaystyle 2x+1} . This yields the recurrence
When the values are tabulated of n {\displaystyle n} and f ( n ) {\displaystyle f(n)} a pattern emerges ( OEIS : A006257 , also the leftmost column of blue numbers in the figure above):
This suggests that f ( n ) {\displaystyle f(n)} is an increasing odd sequence that restarts with f ( n ) = 1 {\displaystyle f(n)=1} whenever the index n is a power of 2 .
Therefore, if m and l are chosen so that n = 2 m + l {\displaystyle n=2^{m}+l} and 0 ≤ l < 2 m {\displaystyle 0\leq l<2^{m}} , then f ( n ) = 2 l + 1 {\displaystyle f(n)=2l+1} .
It is clear that values in the table satisfy this equation. Or it can be thought that after l people are dead there are only 2 m {\displaystyle 2^{m}} people and it goes to the 2 l + 1 {\displaystyle 2l+1} st person. This person must be the survivor. So f ( n ) = 2 l + 1 {\displaystyle f(n)=2l+1} . Below, a proof is given by induction .
Theorem: If n = 2 m + l {\displaystyle n=2^{m}+l} and 0 ≤ l < 2 m {\displaystyle 0\leq l<2^{m}} , then f ( n ) = 2 l + 1 {\displaystyle f(n)=2l+1} .
Proof: The strong induction is used on n . The base case n = 1 {\displaystyle n=1} is true.
The cases are considered separately when n is even and when n is odd.
If n is even, then choose l 1 {\displaystyle l_{1}} and m 1 {\displaystyle m_{1}} such that n / 2 = 2 m 1 + l 1 {\displaystyle n/2=2^{m_{1}}+l_{1}} and 0 ≤ l 1 < 2 m 1 {\displaystyle 0\leq l_{1}<2^{m_{1}}} . Note that l 1 = l / 2 {\displaystyle l_{1}=l/2} . f ( n ) = 2 f ( n / 2 ) − 1 = 2 ( ( 2 l 1 ) + 1 ) − 1 = 2 l + 1 {\displaystyle f(n)=2f(n/2)-1=2((2l_{1})+1)-1=2l+1} is had where the second equality follows from the induction hypothesis.
If n is odd, then choose l 1 {\displaystyle l_{1}} and m 1 {\displaystyle m_{1}} such that ( n − 1 ) / 2 = 2 m 1 + l 1 {\displaystyle (n-1)/2=2^{m_{1}}+l_{1}} and 0 ≤ l 1 < 2 m 1 {\displaystyle 0\leq l_{1}<2^{m_{1}}} . Note that l 1 = ( l − 1 ) / 2 {\displaystyle l_{1}=(l-1)/2} . f ( n ) = 2 f ( ( n − 1 ) / 2 ) + 1 = 2 ( ( 2 l 1 ) + 1 ) + 1 = 2 l + 1 {\displaystyle f(n)=2f((n-1)/2)+1=2((2l_{1})+1)+1=2l+1} is had where the second equality follows from the induction hypothesis. This completes the proof.
l can be solved to get an explicit expression for f ( n ) {\displaystyle f(n)} :
The most elegant form of the answer involves the binary representation of size n : f ( n ) {\displaystyle f(n)} can be obtained by a one-bit left cyclic shift of n itself. If n is represented in binary as n = 1 b 1 b 2 b 3 … b m {\displaystyle n=1b_{1}b_{2}b_{3}\dots b_{m}} , then the solution is given by f ( n ) = b 1 b 2 b 3 … b m 1 {\displaystyle f(n)=b_{1}b_{2}b_{3}\dots b_{m}1} . The proof of this follows from the representation of n as 2 m + l {\displaystyle 2^{m}+l} or from the above expression for f ( n ) {\displaystyle f(n)} .
Implementation: If n denotes the number of people, the safe position is given by the function f ( n ) = 2 l + 1 {\displaystyle f(n)=2l+1} , where n = 2 m + l {\displaystyle n=2^{m}+l} and 0 ≤ l < 2 m {\displaystyle 0\leq l<2^{m}} .
Now if the number is represented in binary format, the first bit denotes 2 m {\displaystyle 2^{m}} and remaining bits will denote l . For example, when n = 41 {\displaystyle n=41} , its binary representation is:
The easiest way to find the safe position is by using bitwise operators . In this approach, shifting the most-significant set bit of n to the least significant bit will return the safe position. [ 11 ] Input must be a positive integer .
In 1997, Lorenz Halbeisen and Norbert Hungerbühler discovered a closed-form for the case k = 3 {\displaystyle k=3} . They showed that there is a certain constant
that can be computed to arbitrary precision. Given this constant, choose m to be the greatest integer such that round ( α ⋅ ( 3 / 2 ) m ) ≤ n {\displaystyle \operatorname {round} (\alpha \cdot (3/2)^{m})\leq n} (this will be either m ′ = round ( log 3 / 2 n / α ) {\displaystyle m^{\prime }=\operatorname {round} (\log _{3/2}n/\alpha )} or m ′ − 1 {\displaystyle m^{\prime }-1} ). Then, the final survivor is
for all n ≥ 5 {\displaystyle n\geq 5} .
As an example computation, Halbeisen and Hungerbühler give n = 41 , k = 3 {\displaystyle n=41,k=3} (which is actually the original formulation of Josephus' problem). They compute:
This can be verified by looking at each successive pass on the numbers 1 through 41 :
Dynamic programming is used to solve this problem in the general case by performing the first step and then using the solution of the remaining problem. When the index starts from one, then the person at s {\displaystyle s} shifts from the first person is in position ( ( s − 1 ) mod n ) + 1 {\displaystyle ((s-1){\bmod {n}})+1} , where n is the total number of people. Let f ( n , k ) {\displaystyle f(n,k)} denote the position of the survivor. After the k {\displaystyle k} -th person is killed, a circle of n − 1 {\displaystyle n-1} remains, and the next count is started with the person whose number in the original problem was ( k mod n ) + 1 {\displaystyle (k{\bmod {n}})+1} . The position of the survivor in the remaining circle would be f ( n − 1 , k ) {\displaystyle f(n-1,k)} if counting is started at 1 {\displaystyle 1} ; shifting this to account for the fact that the starting point is ( k mod n ) + 1 {\displaystyle (k{\bmod {n}})+1} yields the recurrence [ 12 ]
which takes the simpler form
if the positions are numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} instead.
This approach has running time O ( n ) {\displaystyle O(n)} , but for small k {\displaystyle k} and large n {\displaystyle n} there is another approach. The second approach also uses dynamic programming but has running time O ( k log n ) {\displaystyle O(k\log n)} . It is based on considering killing k -th, 2 k -th, ..., ( ⌊ n / k ⌋ k ) {\displaystyle (\lfloor n/k\rfloor k)} -th people as one step, then changing the numbering. [ citation needed ]
This improved approach takes the form | https://en.wikipedia.org/wiki/Josephus_problem |
Josette Garnier is a French biogeochemist. She is research director at the French National Centre for Scientific Research (CNRS). [ 1 ] She won the 2016 Ruth Patrick Award. [ 2 ] [ 3 ]
She graduated from Pierre and Marie Curie University . [ 4 ] She studied the price of land in the 1700s [ 5 ] and the Riverstrahler model of river nutrient transfer. [ 6 ]
This article about a French chemist is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Josette_Garnier |
Joshua Jortner ( Hebrew : יהושע יורטנר ; March 14, 1933) is an Israeli physical chemist . He is a professor emeritus at the School of Chemistry, The Sackler Faculty of Exact Sciences, Tel Aviv University in Tel Aviv, Israel . [ 1 ]
Jortner was born on March 14, 1933, in Tarnów , Poland, to a Jewish family. He migrated with his parents to Palestine under the British Mandate during the Second World War in 1940. He received his Ph.D. from the Hebrew University of Jerusalem in 1960.
After completing his Ph.D., Jortner became a lecturer in the Department of Physical Chemistry at the Hebrew University of Jerusalem from 1961 to 1963. From 1962 to 1964, he was a research associate at the University of Chicago . In 1964, he was appointed to a professorship in the Department of Chemistry at Tel Aviv University and was its first chairman. From 1966 to 1972, he was deputy rector, acting rector and vice president of Tel Aviv University. Since 1973, he has held the position of the Heinemann Professor of Chemistry at the School of Chemistry, the Raymond and Beverly Sackler Faculty of Exact Sciences of Tel Aviv University. He also held a professorship at the University of Chicago from 1964 to 1971 as a part-time appointment. He was a visiting professor at the University of Copenhagen in 1974 and 1978 and at the University of California, Berkeley , in 1975.
He also held honorary fellowships, lectureships and chairs at the California Institute of Technology in 1997, St Catherine's College, Oxford , in 1995 and the École Normale Supérieure in Paris from 1998 to 2000. Since 1973, he has been a member of the Israel Academy of Sciences and Humanities and was its president from 1986 to 1995. He is an Honorary Foreign Member of 13 Academies of Sciences in the United States, Europe (The Netherlands, 1998) [ 2 ] and Asia.
Jortner has undertaken research on a broad range of areas in both physical and theoretical chemistry , involving dynamical phenomena in chemical systems. His research focuses on the relations between structure, spectroscopy, dynamics and function in microscopic and macroscopic systems. He made some central contributions to the elucidation of the mechanisms of energy acquisition, storage and disposal in large molecules, clusters, condensed phase and biophysical systems, as explored from the microscopic point of view.
He is known for the recognition and elucidation of the intramolecular nature of radiationless dissipation of energy in molecules of large and medium size. Based on a simple theoretical model, in 1968 he proposed, in collaboration with Mordechai Bixon, the basic notions specifying the energy acquisition process, the interstate coupling modes, and the mechanisms of energy disposal were laid open. Subsequently, he developed the theory of molecular wavepacket dynamics and quantum beats.
His contributions became seminal to the study of laser chemistry, multiphoton processes in molecules, relaxation phenomena in condensed phases and the dynamics of biophysical systems, and had an indelible impact on the modern development of chemical physics and theoretical chemistry .
His research covers a vast range of fields, such as the theory of solvated electrons , properties of excited electronic states of molecules, coherent multiphoton processes, charge transfer in polar solvents and in biophysical systems and the dynamics of supercooled large molecules and of molecular clusters.
He is married to Ruth T. Jortner, a cardiologist . His son Roni is a biologist and his daughter Iris is a cellist . | https://en.wikipedia.org/wiki/Joshua_Jortner |
A Josiphos ligand is a type of chiral diphosphine which has been modified to be substrate -specific; they are widely used for enantioselective synthesis . [ 2 ] They are widely used in asymmetric catalysis. [ 3 ]
Modern enantioselective synthesis typically applies a well-chosen homogeneous catalyst for key steps. The ligands on these catalysts confer chirality. The Josiphos family of privileged ligands provides especially high yields in enantioselective synthesis. [ 4 ] [ 5 ]
In the early 1990s, Antonio Togni began studying at the Ciba (now Novartis ) Central Research Laboratories [ 6 ] previously-known [ 7 ] ferrocenyl ligands for a Au(I) -catalyzed aldol reaction . [ 6 ] Togni's team began considering diphosphine ligands, and technician Josi Puleo prepared the first ligands with secondary phosphines. The team applied Puleo's products in an Ru -catalyzed enamide hydrogenation synthesis; in a dramatic success, the reaction had e.e. >99% and a turnover frequency (TOF) 0.3 s −1 . [ 6 ] [ 7 ] The same ligand proved useful in production of (S)-metolachlor , active ingredient in the most common herbicide in the United States. Synthesis requires enantioselective hydrogenation of an imine ; after introduction of the catalyst, the reaction proceeds with 100% conversion, turnover number (TON) >7mil, and turnover frequency >0.5 ms −1 . This process is the largest-scale application of enantioselective hydrogenation, producing over 10 kilotons/year of the desired product with 79% e.e. [ 2 ] [ 1 ]
Josiphos ligands also serve in non-enantioselective reactions: a Pd-catalyzed reaction of aryl chlorides and aryl vinyl tosylates with TON of 20,000 or higher, [ 8 ] catalytic carbonylation, [ 9 ] or Grignard and Negishi couplings [ 10 ] [ 11 ] A variety of Josiphos ligands are commercially available under licence from Solvias . The (R-S) and its enantiomer provide higher yields and enantioselectivities than the diastereomer (R,R). [ 1 ]
The ferrocene scaffold has proved to be versatile. [ 12 ] [ 13 ] [ 14 ]
The consensus for the naming is abbreviating the individual ligand as (R)-(S)-R 2 PF-PR' 2 . The substituent on the Cp is written in front of the F and the R on the chiral center after the F. [ 2 ]
Some reactions that are accomplished using M-Josiphos complexes as catalyst are listed below. Other reactions where Josiphos ligands can be used are: hydrogenation of C=N, C=C and C=O bonds , catalyzed allylic substitution , hydrocarboxylation , Michael addition , allylic alkylation , Heck-type reactions , oxabicycle ring-opening , and allylamine isomerization. [ citation needed ]
Many variations of Josiphos ligands have been reported. One family is prepared from Ugi's amine .
An important improvement on initial syntheses has been using N(CH 3 ) 2 as a leaving group over acetate , although an acetic acid solvent gives better yields. [ 6 ]
Clevenger, Andrew L.; Stolley, Ryan M.; Aderibigbe, Justis; Louie, Janis (2020). "Trends in the Usage of Bidentate Phosphines as Ligands in Nickel Catalysis". Chemical Reviews . 120 (13): 6124– 6196. doi : 10.1021/acs.chemrev.9b00682 . PMID 32491839 . | https://en.wikipedia.org/wiki/Josiphos_ligands |
In scattering theory , the Jost function is the Wronskian of the regular solution and the (irregular) Jost solution to the differential equation − ψ ″ + V ψ = k 2 ψ {\displaystyle -\psi ''+V\psi =k^{2}\psi } .
It was introduced by Res Jost .
We are looking for solutions ψ ( k , r ) {\displaystyle \psi (k,r)} to the radial Schrödinger equation in the case ℓ = 0 {\displaystyle \ell =0} ,
A regular solution φ ( k , r ) {\displaystyle \varphi (k,r)} is one that satisfies the boundary conditions,
If ∫ 0 ∞ r | V ( r ) | < ∞ {\displaystyle \int _{0}^{\infty }r|V(r)|<\infty } , the solution is given as a Volterra integral equation ,
There are two irregular solutions (sometimes called Jost solutions) f ± {\displaystyle f_{\pm }} with asymptotic behavior f ± = e ± i k r + o ( 1 ) {\displaystyle f_{\pm }=e^{\pm ikr}+o(1)} as r → ∞ {\displaystyle r\to \infty } . They are given by the Volterra integral equation ,
If k ≠ 0 {\displaystyle k\neq 0} , then f + , f − {\displaystyle f_{+},f_{-}} are linearly independent. Since they are solutions to a second order differential equation, every solution (in particular φ {\displaystyle \varphi } ) can be written as a linear combination of them.
The Jost function is
ω ( k ) := W ( f + , φ ) ≡ φ r ′ ( k , r ) f + ( k , r ) − φ ( k , r ) f + , r ′ ( k , r ) {\displaystyle \omega (k):=W(f_{+},\varphi )\equiv \varphi _{r}'(k,r)f_{+}(k,r)-\varphi (k,r)f_{+,r}'(k,r)} ,
where W is the Wronskian . Since f + , φ {\displaystyle f_{+},\varphi } are both solutions to the same differential equation, the Wronskian is independent of r. So evaluating at r = 0 {\displaystyle r=0} and using the boundary conditions on φ {\displaystyle \varphi } yields ω ( k ) = f + ( k , 0 ) {\displaystyle \omega (k)=f_{+}(k,0)} .
The Jost function can be used to construct Green's functions for
In fact,
where r ∧ r ′ ≡ min ( r , r ′ ) {\displaystyle r\wedge r'\equiv \min(r,r')} and r ∨ r ′ ≡ max ( r , r ′ ) {\displaystyle r\vee r'\equiv \max(r,r')} .
The analyticity of the Jost function in the particle momentum k {\displaystyle k} allows to establish a relationship between
the scatterung phase difference with infinite and zero momenta on one hand
and the number of bound states n b {\displaystyle n_{b}} , the number of Jaffe - Low primitives n p {\displaystyle n_{p}} ,
and the number of Castillejo - Daliz - Dyson poles n CDD {\displaystyle n_{\text{CDD}}} on the other ( Levinson's theorem ):
Here δ ( k ) {\displaystyle \delta (k)} is the scattering phase and n 0 {\displaystyle n_{0}} = 0 or 1. The value n 0 = 1 {\displaystyle n_{0}=1} corresponds to the exceptional case of a s {\displaystyle s} -wave
scattering in the presence of a bound state with zero energy.
This scattering –related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Jost_function |
Jostel's TSH index ( TSHI or JTI ), also referred to as Jostel's thyrotropin index or Thyroid Function index ( TFI ), is a method for estimating the thyrotropic (i.e. thyroid stimulating) function of the anterior pituitary lobe in a quantitative way. [ 1 ] [ 2 ] The equation has been derived from the logarithmic standard model of thyroid homeostasis . [ 3 ] [ 4 ] [ 5 ] [ 6 ] In a paper from 2014 further study was suggested to show if it is useful, [ 7 ] but the 2018 guideline by the European Thyroid Association for the diagnosis of uncertain cases of central hypothyroidism regarded it as beneficial. [ 2 ] It is also recommended for purposes of differential diagnosis in the sociomedical expert assessment . [ 8 ]
Jostel's TSH index can be calculated with
from equilibrium serum concentrations of thyrotropin (TSH), free T4 (FT4) and a correction coefficient derived from the logarithmic standard model (β = 0.1345).
An alternative standardised form ( standardised TSH index or sTSHI ) is calculated with. [ 1 ]
as a z-transformed value incorporating mean (2.7) and standard deviation (0.676) of TSHI in a reference population [ 5 ]
The TSH index is reduced in patients with secondary hypothyroidism resulting from thyrotropic insufficiency. [ 1 ] [ 9 ] [ 10 ] [ 11 ] For this indication, it has, however, up to now only been validated in adults. [ 12 ] JTI was also found reduced in cases of TACITUS syndrome (non-thyroidal illness syndrome) as an example of type 1 thyroid allostasis . [ 13 ] [ 14 ] Conversely, an elevated thyroid function index may serve as a biomarker for type 2 allostasis and contextual stress. [ 15 ] [ 16 ]
Jostel's TSH index may decrease under therapy with the antidiabetic drug metformin , [ 17 ] especially in women under oral contraceptives . [ 18 ]
In two large population-based cohorts included in the Study of Health in Pomerania differentially correlated to some markers of body composition . Correlation was positive to body mass index (BMI), waist circumference and fat mass, but negative to body cell mass. [ 19 ] With the exception of fat mass all correlations were age-dependent. [ 19 ] Very similar observations have been made earlier in the NHANES dataset. [ 20 ]
In Parkinson's disease , JTI is significantly elevated in early sub-types of the disease compared to an advanced group. [ 21 ]
A longitudinal study in euthyroid subjects with structural heart disease found that JTI predicts the risk of malignant arrhythmia including ventricular fibrillation and ventricular tachycardia . [ 22 ] This applies to both incidence and event-free survival. [ 22 ] A second study in a different population undergoing coronary angiography arrived at similar results. [ 23 ] It was therefore concluded that an elevated set point of thyroid homeostasis may contribute to cardiovascular risk. A positive correlation of JTI to SIQALS 2, [ 16 ] a score for allostatic load , suggests that thyroid hormones are among the mediators linking stress to major cardiovascular endpoints. [ 24 ]
Jostel's TSH index and the thyroid feedback quantile-based index , another biomarker for the central thyrotropic function, were observed to be elevated in certain psychiatric diseases including schizophrenia. [ 25 ]
Another study demonstrated the TSH index to inversely correlate to thyroid's secretory capacity and thyroid volume. [ 26 ] It is unclear if this finding reflects shortcomings of the index (i.e. low specificity in the setting of subclinical hypothyroidism) or plastic responses of the pituitary gland to beginning hypothyroidism. [ citation needed ]
In subjects with type 2 diabetes , treatment with beta blockers resulted in increased TSH index, but the mechanism is unclear. [ 27 ]
Negative correlation of Jostel's TSH index to the urinary excretion of certain phthalates suggests that endocrine disruptors may affect the central set point of thyroid homeostasis. [ 28 ]
Drugs that reduce the TSH index, probably via effects on the central set point of the feedback loop, include mirtazapine [ 29 ] and oxcarbazepine. [ 30 ]
A reduction of Jostel's TSH index may predict the development of hypophysitis due to therapy with immune checkpoint inhibitors , e. g. ipilimumab . [ 31 ] | https://en.wikipedia.org/wiki/Jostel's_TSH_index |
José Joaquín Barluenga Mur (27 July 1940 – 7 September 2016) [ 1 ] [ 2 ] was a Spanish chemist known for his research in organometallic chemistry . He was a professor of chemistry at Oviedo University until his retirement in 2014.
Barluenga was born in Tardienta (Huesca), Spain, where he spent his childhood and attended primary school.
He studied chemistry at the University of Zaragoza (B.Sc., 1963; Ph.D. 1966) with Professor V. Gómez Aranda. In 1967, he moved to Germany and, after a postdoctoral appointment at the Max-Planck Institut für Kohlenforschung in Mülheim an der Ruhr (1967–1970, Professor H. Hoberg), he returned to Spain to hold research positions at the Spanish Council for Scientific Research in Zaragoza (1970–1972) and University of Zaragoza (1972–1975).
He joined the faculty of University of Oviedo as Professor of Chemistry in 1975 and became Emeritus Professor in 2010 after 35 years of service at the university.
He has supervised 120 Ph.D. students of whom 18 have hold positions as Professors of Chemistry at different Spanish universities. [ 3 ] His laboratory has been active in the field of organic chemistry with research interests in synthetic methodology development of transition-metal reagents, stoichiometric and catalytic processes. [ 4 ] [ 5 ] [ 6 ]
He discovered the bis(pyridine)iodonium tetrafluoroborate (IPy 2 BF 4 ), an iodinating reagent now named after him which is available from numerous chemical suppliers worldwide. [ 7 ] One of his papers [ 4 ] on the use of the reagent is his most cited article, with 223 citations through September 2014 according to Google Scholar . [ 8 ] Other papers of his on this topic have had as many as 170 and 172 citations. [ 8 ] | https://en.wikipedia.org/wiki/José_Barluenga |
José Manuel Rodríguez Delgado (August 8, 1915 – September 15, 2011) was a Spanish professor of neurophysiology at Yale University , famed for his research on mind control through electrical stimulation of the brain . [ 1 ]
Rodríguez Delgado was born in Ronda , in the province of Málaga , Spain in 1915. He received a Doctor of Medicine degree from the University of Madrid just before the outbreak of the Spanish Civil War . During the Spanish Civil War he joined the Republican side and served as a medical corpsman while he was a medical student. Rodríguez Delgado was held in a concentration camp for five months after the war ended. [ 2 ] After serving in the camp, he had to repeat his M.D. degree, and then gained a PhD at the Ramón y Cajal Institute in Madrid .
Rodríguez Delgado's father was an eye doctor and he had planned to follow in his footsteps. However, once he discovered the writings of Santiago Ramón y Cajal , a Nobel laureate in 1906, and after having spent some time in a physiology laboratory, Delgado no longer wanted to be an eye doctor. Delgado became captivated by "the many mysteries of the brain. How little was known then. How little is known now!" [ 2 ]
In 1946 Rodríguez Delgado won a fellowship at Yale University in the department of physiology under the direction of John F. Fulton . In 1950, Rodríguez Delgado accepted a position in the physiology department which at the time was headed by John Fulton. By 1952, he had co-authored his first paper on implanting electrodes into humans. [ 2 ]
The Spanish minister of Education, Villar Palasí, asked Rodríguez Delgado to help organize a new medical school at the Autonomous University of Madrid . Rodríguez Delgado accepted Palasí's proposal and relocated to Spain with his wife and two children in 1974. [ 2 ]
Rodríguez Delgado had last moved with his wife, Caroline, to San Diego , California before his death on September 15, 2011. [ 2 ]
Rodríguez Delgado's research interests centered on the use of electrical signals to evoke responses in the brain. His earliest work was with cats, but he later did experiments with monkeys and humans, including psychiatric patients. [ 3 ] [ 4 ]
Much of Rodríguez Delgado's work was with an invention he called a stimoceiver , a radio which joined a stimulator of brain waves with a receiver which monitored EEG waves and sent them back on separate radio channels. Some of these stimoceivers were as small as half-dollars. This allowed the subject of the experiment full freedom of movement while allowing the experimenter to control the experiment. This was a great improvement from his early equipment which included visual disturbance in those whose wires ran from the brain to bulky equipment that both recorded data and delivered the desired electrical charges to the brain. This early equipment, while not allowing for a free range of movement, was also the cause of infection in many subjects. [ 5 ]
The stimoceiver could be used to stimulate emotions and control behavior. According to Rodríguez Delgado, "Stimulation of different points in the amygdala and hippocampus in the four patients produced a variety of effects, including pleasant sensations, elation, deep, thoughtful concentration, odd feelings, super relaxation, colored visions, and other responses." Rodríguez Delgado stated that "brain transmitters can remain in a person's head for life. The energy to activate the brain transmitter is transmitted by way of radio frequencies." [ 6 ]
Using the stimoceiver, Rodríguez Delgado found that he could not only elicit emotions, but he could also elicit specific physical reactions. These specific physical reactions, such as the movement of a limb or the clenching of a fist, were achieved when Rodríguez Delgado stimulated the motor cortex. Individuals whose implants were stimulated to produce a reaction were unable to resist the reaction, with one patient remarking, "I guess, doctor, that your electricity is stronger than my will." One of Rodríguez Delgado's most promising finds is related to an area called the septum verum , a structure within the brain's limbic system . This area, when stimulated by Rodríguez Delgado, produced feelings of strong euphoria. These euphoric feelings were sometimes strong enough to overcome physical pain and depression. [ 2 ]
Rodríguez Delgado created many inventions and was called a "technological wizard" by one of his Yale colleagues. Other than the stimoceiver, Rodríguez Delgado also created a "chemitrode" which was an implantable device that released controlled amounts of a drug into specific brain areas. Rodríguez Delgado also invented an early version of what is now a cardiac pacemaker . [ 2 ]
In Rhode Island, Rodríguez Delgado did some work at what is now a closed mental hospital. He chose patients who were "desperately ill patients whose disorders had resisted all previous treatments" and implanted electrodes in about 25 of them. Most of these patients were either schizophrenics or epileptics. [ 7 ] To determine the best placement of electrodes within the human patients, Delgado initially looked to the work of Wilder Penfield , who studied epileptics' brains in the 1930s, as well as earlier animal experiments, and studies of brain-damaged people. [ 2 ]
The most famous example of the stimoceiver in action occurred at a Córdoba bull breeding ranch. Rodríguez Delgado stepped into the ring with a bull which had had a stimoceiver implanted within its brain. The bull charged Delgado, who pressed a remote control button which caused the bull to stop its charge. Always one for theatrics, he taped this stunt and it can be seen today. [ 8 ] The region of the brain Rodríguez Delgado stimulated when he pressed the hand-held transmitter was the caudate nucleus . This region was chosen to be stimulated because the caudate nucleus is involved in controlling voluntary movements. [ 2 ] Rodríguez Delgado claimed that the stimulus caused the bull to lose its aggressive instinct.
It has been argued that it was easier to block motor control than motivation or feelings.
However, the public understood that mind control was near. [ 9 ]
Although the bull incident was widely mentioned in popular media, Rodríguez Delgado believed that his experiment with a female chimpanzee named Paddy was more significant. Paddy was fitted with a stimoceiver linked to a computer that detected the brain signal called a spindle which was emitted by her part of the brain called the amygdala . When the spindle was recognized, the stimoceiver sent a signal to the central gray area of Paddy's brain, producing an 'aversive reaction'. In this case, the aversive reaction was an unpleasant or painful feeling. The result of the aversive reaction to the stimulus was a negative feedback to the brain. [ 2 ] Within hours her brain was producing fewer spindles as a result of the negative feedback. [ 10 ] As a result, Paddy became "quieter, less attentive and less motivated during behavioral testing". Although Paddy's reaction was not exactly ideal, Rodríguez Delgado hypothesized that the method used on Paddy could be used on others to stop panic attacks, seizures, and other disorders controlled by certain signals within the brain. [ 2 ] [ 11 ]
José Rodríguez Delgado authored 134 scientific publications within two decades (1950–1970) on electrical stimulation on cats, monkeys and patients – psychotic and non-psychotic. In 1963, New York Times featured his experiments on their front page. Rodríguez Delgado had implanted a stimoceiver in the caudate nucleus of a fighting bull. He could stop the animal mid-way that would come running towards a waving flag. [ 12 ]
He was invited to write his book Physical Control of the Mind: Toward a Psychocivilised Society as the forty-first volume in a series entitled World Perspectives edited by Ruth Nanda Anshen . In it Rodríguez Delgado has discussed how we have managed to tame and civilize our surrounding nature, arguing that now it was time to civilize our inner being. The book has been a centre of controversy since its release. [ 1 ] The tone of the book was challenging and the philosophical speculations went beyond the data. Its intent was to encourage less cruelty, and a more benevolent, happier, better man, however it clashed with religious sentiments .
José Rodríguez Delgado continued to publish his research and philosophical ideas through articles and books for the next quarter century. He in all wrote over 500 articles and six books. His final book in 1989, was named Happiness and had 14 editions. [ 12 ] | https://en.wikipedia.org/wiki/José_Manuel_Rodríguez_Delgado |
José María Asua González (Zarátamo, April 6, 1953) is a Spanish chemist, professor of chemical engineering at the University of the Basque Country and director of Polymat, the Polymeric Materials Research Institute. [ 1 ]
Asua obtained his Bachelor's degree in Chemistry from the University of Bilbao in 1975, and completed his PhD in Chemistry at the University of Zaragoza, researching the deactivation of solid catalysts. [ 2 ]
In 1978, he joined the Faculty of Chemical Sciences at the University of the Basque Country to research the subject of polymerization reactors. [ 2 ] He completed a post-doctoral stay at the University of Liège (Belgium) investigating the hydrodynamics of trickle bed reactors (TBR), [ 3 ] and has spent sabbatical years at Lehigh University (USA) as a Fulbright scholar and at the University of Waterloo (Canada) as a visiting professor. [ citation needed ]
He is also a visiting professor at the Catholic Universities of Leuven (Belgium) and Dortmund (Germany). [ 4 ] Professor Asua has worked in industrially important polymerization processes, developing knowledge-based strategies for the production of water-dispersed polymers. [ 2 ] He has also been involved in university-industry relations, directing industrial projects; and has been part of the scientific committee of international conferences and director of a NATO Advanced Study Institute. [ 5 ]
Asua is the author of a book and editor of the books 'Polymeric Dispersions: Principles and Applications' (1997) and 'Polymer Reaction Engineering' (2007). He has published more than 230 articles and is co-author of 4 patents. He is a member of the editorial boards of Macromolecular Reaction Engineering, Macromolecular Materials and Engineering and Chemical Engineering Journal, and has been Associate Editor of Polymer Reaction Engineering. He has directed 33 doctoral theses. [ 5 ] | https://en.wikipedia.org/wiki/José_María_Asua |
'Jose H. Zagal Moya (born in Talca Chile, December 19, 1949) is a Chilean scientist educated at the University of Chile with postgraduate training in the United States of America with a Ph.D. degree from Case Western Reserve University, Cleveland Ohio and postdoctoral training at Brookhaven National Laboratory , Upton, New York. At present he is a Distinguished Professor, Department of Chemistry and Materials, Faculty of Chemistry and Biology, Universidad de Santiago de Chile (USACH) where he directs the Laboratory of Electrocatalysis since 1982. He got his Ph.D. in chemistry Case Western Reserve University, US (1978) and was postdoctoral fellow at Brookhaven National Laboratory, Upton, New York, in 1982. His main research efforts are focused on the fundamentals of electron transfer reactions that are relevant for energy conversion and sensors. He has contributed in the area of electrocatalysis, electrodes modified with metal macrocyclics, electrochemistry of biological molecules, the catalysis of the reduction of molecular oxygen and many other reactions of relevance, conductive polymers, electrochemical sensors and in pioneering work in the establishment of non-linear correlations between thermodynamic properties of molecular catalysts and their electrochemical reactivity. These contributions are essential in the development of non-precious metal catalysts for energy conversion devices and electrochemical sensors. [1][2][3]
He also has contributed in the field of corrosion, conductive polymers and his well-known volcano correlations for the electrocatalytic properties of surface-confined molecular catalysts [ 1 ] [ 2 ] [ 3 ]
He was awarded by the President of Chile, Eduardo Frei Ruiz-Tagle the Presidential Chair in Science in 1996 by a Committee chaired by a Nobel Prize in Chemistry Rudolph Marcus and including Physics Nobel Laureate David Gross. He received the Silver Medal “University Merit” in 1998 and the Gold Medal in 2002 and the Manuel Bulnes Medal in 2013. He was distinguished by Conicyt with “Fondecyt Diploma” for being awarded more than 10 consecutive research grants without rejects in 2012. He still remains unbeaten in Fondecyt. He has been awarded two Milenium Projects as Alternative Responsible Scientist and has participated in many other associative research projects in Chile and abroad. He was appointed by the President of Chile Sebastian Piñera Echeñique and the Minister of Education, Member of the Superior Council of Research of Conicyt for the period 2010–2013. In 2014 he received the Dr. Alberto Zanlungo Prize. He has received several distinctions from international scientific societies. He was appointed Fellow by the Royal Society of Chemistry (RSC) of the UK in 2018. He became a Member of the RSC in 2017. He received the Fellow Medal from the International Society of Electrochemistry based in Europe and the Fellow Medal from the US-based Electrochemical Society (ECS) both in 2014. This year he was incorporated as an Active Member to the Academy of Sciences of Latin America (ACAL) and became an Emeritus Member of The Electrochemical Society of the United States of America. He created the Chilean Secretary of ISE in 2003 and was his first chilean representative. He also created the Chile Section of ECS in 2011 and is presently its Chairman. He was a co-founder of the Chilean Society of Carbonaceous Materials and is presently its President. He is also the President of the Iberoamerican Chemical Society.
In 2024 he was awarded Chile's highest honor for scientific merit, the "Premio Nacional de Ciencias Naturales" or "National Prize in the Natural Sciences". [ 4 ]
He has published over 222 papers (200 indexed publications) coedited four books, 9 book chapters and 3 patents. H impact factor= 41 (Web of Science), H= 42 Scopus and H= 48 (Google Scholar) with more 7460 citations in Google. He has created three patents with the Chilean Navy on electrode materials for energy conversion. He has presented more than 300 papers in national and international meetings, including some plenary and invited lectures and keynotes worldwide. He has been a guest editor for the Journal of Applied Electrochemistry, The International Journal of Electrochemistry and recently in Current Opinion in Electrochemistry
He was involved in the creation of the Masters and Ph.D. Programs in Chemistry from his university and it was the very first doctoral program in Usach. He has supervised more 60 thesis: 36 undergraduate and professional students: 20 doctorates, 5 masters and 9 postdocs, some coming from Europe (Russian Federation, France, Germany, Spain and Italy).
1) N4 Macrocyclic Metal Complexes . J.H. ZAGAL, F. Bedioui, J.P. Dodelet (Eds), Springer New York ( 2006).
3https://www.springer.com/la/book/9783319311708) “Electrochemistry of MN4 macrocyclic metal complexes” Volume 1 Energy: “Electrochemistry of MN4 Macrocyclic complexes” J.H. Zagal, F. Bedioui (Eds) Springer Switzerland (2016) (segunda edición) 316 páginas.
4) https://www.springer.com/gb/book/9783319313306 “Electrochemistry of MN4 macrocyclic metal complexes” Volume 2 Biomimesis, Electroanalysis, and Electrosynthesis of MN4 complexes” J.H. Zagal, F. Bedioui, (Eds) Springer Switzerland (2016) (segunda edición) 436 páginas
He has been involved in many editorial boards of scientific journals. He was member of the editorial board of the Journal of Applied Electrochemistry (1988-2010), Journal of the Chilean Chemical Society (1984-2007) and Electrocatalysis (2010-2015) and is presently member of the Editorial Board of several international publications: Journal of Solid State Electrochemistry (Springer), International Journal of Electrochemistry (Hindawi), Electrochemistry Communications (Elsevier), Journal of the Serbian Chemical Society , Electrochemical Energy Technology (De Goutyer) and Chimica Nova and Frontiers in Chemistry. He has been a Guest Editor for the Journal of Applied Electrochemistry, Current Opinion in Electrochemistry and for the International Journal of Electrochemistry.
Professor Zagal is also a man of many talents: he sings and plays several instruments, including the guitar and the scottish bagpipes. He also writes poetry, paints and draws cartoons. He played Caiphas in the Opera Rock Jesus Christ Superstar in the early 70's. He has been a volunteer firemen with the 14th British and Commonwealth Fire & Rescue Company in Santiago since 1972 and is also the official piper of his company. Some of his caricatures have been published in the magazine “Interface” of the Electrochemical Society and in the Journal of the Serbian Chemical Society. He is a devoted train enthusiast. He has built large replicas or working steam locomotive and full size freight wagons. He also collects full size railway items including 12 wagons and 2 locomotives, one steam and an electric locomotive. With other enthusiasts he started in the 80's the "Chilean Association for the Preservation of the Railways". With two other enthusiasts he owns the "Puangue Station" which is one of the few preserved railway stations in rural areas. | https://en.wikipedia.org/wiki/José_Zagal_Moya |
In algebraic geometry , Jouanolou's trick is a theorem that asserts, for an algebraic variety X , the existence of a surjection with affine space fibers from an affine variety W to X . Moreover, the variety W is homotopy-equivalent to X , and W has the technically advantageous property of being affine. Jouanolou's original statement of the theorem required that X be quasi-projective over an affine scheme, but this has since been considerably weakened.
Jouanolou's original statement was:
By the definition of a torsor, W comes with a surjective map to X and is Zariski-locally on X an affine space bundle.
Jouanolou's proof used an explicit construction. Let S be an affine scheme and X = P S r {\displaystyle X=\mathbf {P} _{S}^{r}} . Interpret the affine space A S ( r + 1 ) 2 {\displaystyle \mathbf {A} _{S}^{(r+1)^{2}}} as the space of ( r + 1) × ( r + 1) matrices over S . Within this affine space, there is a subvariety W consisting of idempotent matrices of rank one. The image of such a matrix is therefore a point in X , and the map W → X {\displaystyle W\to X} that sends a matrix to the point corresponding to its image is the map claimed in the statement of the theorem. To show that this map has the desired properties, Jouanolou notes that there is a short exact sequence of vector bundles:
where the first map is defined by multiplication by a basis of sections of O X ( 1 ) {\displaystyle {\mathcal {O}}_{X}(1)} and the second map is the cokernel. Jouanolou then asserts that W is a torsor for E = Hom ( F , O X ( − 1 ) ) {\displaystyle {\mathcal {E}}=\operatorname {Hom} ({\mathcal {F}},{\mathcal {O}}_{X}(-1))} .
Jouanolou deduces the theorem in general by reducing to the above case. If X is projective over an affine scheme S , then it admits a closed immersion into some projective space P S r {\displaystyle \mathbf {P} _{S}^{r}} . Pulling back the variety W constructed above for P S r {\displaystyle \mathbf {P} _{S}^{r}} along this immersion yields the desired variety W for X . Finally, if X is quasi-projective, then it may be realized as an open subscheme of a projective S -scheme. Blow up the complement of X to get X ¯ {\displaystyle {\bar {X}}} , and let i : X → X ¯ {\displaystyle i\colon X\to {\bar {X}}} denote the inclusion morphism. The complement of X in X ¯ {\displaystyle {\bar {X}}} is a Cartier divisor, and therefore i is an affine morphism. Now perform the previous construction for X ¯ {\displaystyle {\bar {X}}} and pull back along i .
Robert Thomason observed that, by making a less explicit construction, it was possible to obtain the same conclusion under significantly weaker hypotheses. Thomason's construction first appeared in a paper of Weibel. Thomason's theorem asserts:
Having an ample family of line bundles was first defined in SGA 6 Exposé II Définition 2.2.4. Any quasi-projective scheme over an affine scheme has an ample family of line bundles, as does any separated locally factorial Noetherian scheme.
Thomason's proof abstracts the key features of Jouanolou's. By hypothesis, X admits a set of line bundles L 0 , ..., L N and sections s 0 , ..., s N whose non-vanishing loci are affine and cover X . Define X i to be the non-vanishing locus of s i , and define E {\displaystyle {\mathcal {E}}} to be the direct sum of L 0 , ..., L N . The sections define a morphism of vector bundles s = ( s 0 , … , s N ) : O X → E {\displaystyle s=(s_{0},\ldots ,s_{N})\colon {\mathcal {O}}_{X}\to {\mathcal {E}}} . Define F {\displaystyle {\mathcal {F}}} to be the cokernel of s . On X i , s is a split monomorphism since it is inverted by the inverse of s i . Therefore F {\displaystyle {\mathcal {F}}} is a vector bundle over X i , and because these open sets cover X , F {\displaystyle {\mathcal {F}}} is a vector bundle.
Define P ( E ) = Proj Sym ∗ E {\displaystyle \mathbf {P} ({\mathcal {E}})=\operatorname {Proj} \operatorname {Sym} ^{*}{\mathcal {E}}} and similarly for P ( F ) {\displaystyle \mathbf {P} ({\mathcal {F}})} . Let W be the complement of P ( F ) {\displaystyle \mathbf {P} ({\mathcal {F}})} in P ( E ) {\displaystyle \mathbf {P} ({\mathcal {E}})} . There is an equivalent description of W as Spec ( Sym ∗ E / ( s − 1 ) ) {\displaystyle \operatorname {Spec} (\operatorname {Sym} ^{*}{\mathcal {E}}/(s-1))} , and from this description, it is easy to check that it is a torsor for F {\displaystyle {\mathcal {F}}} . Therefore the projection π : W → X {\displaystyle \pi \colon W\to X} is affine. To see that W is itself affine, apply a criterion of Serre (EGA II 5.2.1(b), EGA IV 1 1.7.17). Each s i determines a global section f i of W . The non-vanishing locus W i of f i is contained in π − 1 ( X i ) {\displaystyle \pi ^{-1}(X_{i})} , which is affine, and hence W i is affine. The sum of the sections f 0 , ..., f N is 1, so the ideal they generate is the ring of global sections. Serre's criterion now implies that W is affine. | https://en.wikipedia.org/wiki/Jouanolou's_trick |
In polynomial algebra and field theory , Joubert's theorem states that if K {\displaystyle K} and L {\displaystyle L} are fields , L {\displaystyle L} is a separable field extension of K {\displaystyle K} of degree 6, and the characteristic of K {\displaystyle K} is not equal to 2, then L {\displaystyle L} is generated over K {\displaystyle K} by some element λ in L {\displaystyle L} , such that the minimal polynomial p {\displaystyle p} of λ has the form p ( t ) {\displaystyle p(t)} = t 6 + c 4 t 4 + c 2 t 2 + c 1 t + c 0 {\displaystyle t^{6}+c_{4}t^{4}+c_{2}t^{2}+c_{1}t+c_{0}} , for some constants c 4 , c 2 , c 1 , c 0 {\displaystyle c_{4},c_{2},c_{1},c_{0}} in K {\displaystyle K} . [ 1 ] The theorem is named in honor of Charles Joubert, a French mathematician, lycée professor, and Jesuit priest. [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ]
In 1867 Joubert published his theorem in his paper Sur l'équation du sixième degré in tome 64 of Comptes rendus hebdomadaires des séances de l'Académie des sciences . [ 7 ] He seems to have made the assumption that the fields involved in the theorem are subfields of the complex field. [ 1 ]
Using arithmetic properties of hypersurfaces , Daniel F. Coray gave, in 1987, a proof of Joubert's theorem (with the assumption that the characteristic of K {\displaystyle K} is neither 2 nor 3). [ 1 ] [ 8 ] In 2006 Hanspeter Kraft [ de ] gave a proof of Joubert's theorem [ 9 ] "based on an enhanced version of Joubert’s argument". [ 1 ] In 2014 Zinovy Reichstein proved that the condition characteristic( K {\displaystyle K} ) ≠ 2 is necessary in general to prove the theorem, but the theorem's conclusion can be proved in the characteristic 2 case with some additional assumptions on K {\displaystyle K} and L {\displaystyle L} . [ 1 ]
This algebra -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Joubert's_theorem |
Joule effect and Joule's law are any of several different physical effects discovered or characterized by English physicist James Prescott Joule . These physical effects are not the same, but all are frequently or occasionally referred to in the literature as the "Joule effect" or "Joule law" These physical effects include:
Between 1840 and 1843, Joule carefully studied the heat produced by an electric current. From this study, he developed Joule's laws of heating , the first of which is commonly referred to as the Joule effect . Joule's first law expresses the relationship between heat generated in a conductor and current flow, resistance, and time. [ 1 ]
The magnetostriction effect describes a property of ferromagnetic materials which causes them to change their shape when subjected to a magnetic field. Joule first reported observing the change in the length of ferromagnetic rods in 1842. [ 2 ]
In 1845, Joule studied the free expansion of a gas into a larger volume. This became known as Joule expansion . [ 3 ] The cooling of a gas by allowing it to expand freely is occasionally referred to as the Joule effect. [ 4 ]
If an elastic band is first stretched and then subjected to heating, it will shrink rather than expand. This effect was first observed by John Gough in 1802, and was investigated further by Joule in the 1850s, when it then became known as the Gough–Joule effect . [ 5 ] [ 6 ] Examples in Literature: | https://en.wikipedia.org/wiki/Joule_effect |
The Joule expansion (a subset of free expansion ) is an irreversible process in thermodynamics in which a volume of gas is kept in one side of a thermally isolated container (via a small partition), with the other side of the container being evacuated. The partition between the two parts of the container is then opened, and the gas fills the whole container.
The Joule expansion, treated as a thought experiment involving ideal gases , is a useful exercise in classical thermodynamics. It provides a convenient example for calculating changes in thermodynamic quantities, including the resulting increase in entropy of the universe ( entropy production ) that results from this inherently irreversible process. An actual Joule expansion experiment necessarily involves real gases ; the temperature change in such a process provides a measure of intermolecular forces .
This type of expansion is named after James Prescott Joule who used this expansion, in 1845, in his study for the mechanical equivalent of heat, but this expansion was known long before Joule e.g. by John Leslie , in the beginning of the 19th century, and studied by Joseph Louis Gay-Lussac in 1807 with similar results as obtained by Joule. [ 1 ] [ 2 ]
The Joule expansion should not be confused with the Joule–Thomson expansion or throttling process which refers to the steady flow of a gas from a region of higher pressure to one of lower pressure via a valve or porous plug.
The process begins with gas under some pressure, P i {\displaystyle P_{\mathrm {i} }} , at temperature T i {\displaystyle T_{\mathrm {i} }} , confined to one half of a thermally isolated container (see the top part of the drawing at the beginning of this article). The gas occupies an initial volume V i {\displaystyle V_{\mathrm {i} }} , mechanically separated from the other part of the container, which has a volume V 0 {\displaystyle V_{\mathrm {0} }} , and is under near zero pressure. The tap (solid line) between the two halves of the container is then suddenly opened, and the gas expands to fill the entire container, which has a total volume of V f = V i + V 0 {\displaystyle V_{\mathrm {f} }=V_{\mathrm {i} }+V_{\mathrm {0} }} (see the bottom part of the drawing). A thermometer inserted into the compartment on the left (not shown in the drawing) measures the temperature of the gas before and after the expansion.
The system in this experiment consists of both compartments; that is, the entire region occupied by the gas at the end of the experiment. Because this system is thermally isolated, it cannot exchange heat with its surroundings. Also, since the system's total volume is kept constant, the system cannot perform work on its surroundings. [ 3 ] As a result, the change in internal energy , Δ U {\displaystyle \Delta U} , is zero. Internal energy consists of internal kinetic energy (due to the motion of the molecules) and internal potential energy (due to intermolecular forces ). When the molecular motion is random, temperature is the measure of the internal kinetic energy. In this case, the internal kinetic energy is called heat. If the chambers have not reached equilibrium, there will be some kinetic energy of flow, which is not detectable by a thermometer (and therefore is not a component of heat). Thus, a change in temperature indicates a change in kinetic energy, and some of this change will not appear as heat until and unless thermal equilibrium is reestablished. When heat is transferred into kinetic energy of flow, this causes a decrease in temperature. [ 4 ] In practice, the simple two-chamber free expansion experiment often incorporates a 'porous plug' through which the expanding air must flow to reach the lower pressure chamber. The purpose of this plug is to inhibit directional flow, thereby quickening the reestablishment of thermal equilibrium.
Since the total internal energy does not change, the stagnation of flow in the receiving chamber converts kinetic energy of flow back into random motion (heat) so that the temperature climbs to its predicted value.
If the initial air temperature is low enough that non-ideal gas properties cause condensation, some internal energy is converted into latent heat (an offsetting change in potential energy) in the liquid products. Thus, at low temperatures the Joule expansion process provides information on intermolecular forces.
If the gas is ideal, both the initial ( T i {\displaystyle T_{\mathrm {i} }} , P i {\displaystyle P_{\mathrm {i} }} , V i {\displaystyle V_{\mathrm {i} }} ) and final ( T f {\displaystyle T_{\mathrm {f} }} , P f {\displaystyle P_{\mathrm {f} }} , V f {\displaystyle V_{\mathrm {f} }} ) conditions follow the Ideal Gas Law , so that initially P i V i = n R T i {\displaystyle P_{\mathrm {i} }V_{\mathrm {i} }=nRT_{\mathrm {i} }} and then, after the tap is opened, P f V f = n R T f . {\displaystyle P_{\mathrm {f} }V_{\mathrm {f} }=nRT_{\mathrm {f} }.}
Here n {\displaystyle n} is the number of moles of gas and R {\displaystyle R} is the molar ideal gas constant . Because the internal energy does not change and the internal energy of an ideal gas is solely a function of temperature, the temperature of the gas does not change; therefore T i = T f {\displaystyle T_{\mathrm {i} }=T_{\mathrm {f} }} . This implies that P i V i = P f V f = n R T i . {\displaystyle P_{\mathrm {i} }V_{\mathrm {i} }=P_{\mathrm {f} }V_{\mathrm {f} }=nRT_{\mathrm {i} }.}
Therefore if the volume doubles, the pressure halves.
The fact that the temperature does not change makes it easy to compute the change in entropy of the universe for this process.
Unlike ideal gases, the temperature of a real gas will change during a Joule expansion. At temperatures below their inversion temperature gases will cool during Joule expansion, while at higher temperatures they will heat up. [ 5 ] [ 6 ] The inversion temperature of a gas is typically much higher than room temperature; exceptions are helium, with an inversion temperature of about 40 K, and hydrogen, with an inversion temperature of about 200 K. Since the internal energy of the gas during Joule expansion is constant, cooling must be due to the conversion of internal kinetic energy to internal potential energy, with the opposite being the case for warming.
Intermolecular forces are repulsive at short range and attractive at long range (for example, see the Lennard-Jones potential ). Since distances between gas molecules are large compared to molecular diameters, the energy of a gas is usually influenced mainly by the attractive part of the potential. As a result, expanding a gas usually increases the potential energy associated with intermolecular forces. Some textbooks say that for gases this must always be the case and that a Joule expansion must always produce cooling. [ 7 ] [ 8 ] When molecules are close together, however, repulsive interactions are much more important and it is thus possible to get an increase in temperature during a Joule expansion. [ 9 ]
It is theoretically predicted that, at sufficiently high temperature, all gases will warm during a Joule expansion [ 5 ] The reason is that at any moment, a very small number of molecules will be undergoing collisions; for those few molecules, repulsive forces will dominate and the potential energy will be positive. As the temperature rises, both the frequency of collisions and the energy involved in the collisions increase, so the positive potential energy associated with collisions increases strongly. If the temperature is high enough, that can make the total potential energy positive, in spite of the much larger number of molecules experiencing weak attractive interactions. When the potential energy is positive, a constant energy expansion reduces potential energy and increases kinetic energy, resulting in an increase in temperature. This behavior has only been observed for hydrogen and helium; which have very weak attractive interactions. For other gases this "Joule inversion temperature" appears to be extremely high. [ 6 ]
Entropy is a function of state , and therefore the entropy change can be computed directly from the knowledge of the final and initial equilibrium states. For an ideal gas, the change in entropy [ 10 ] is the same as for isothermal expansion where all heat is converted to work: Δ S = ∫ i f d S = ∫ V i V f P d V T = ∫ V i V f n R d V V = n R ln V f V i = N k B ln V f V i . {\displaystyle \Delta S=\int _{\text{i}}^{\text{f}}dS=\int _{V_{\text{i}}}^{V_{\text{f}}}{\frac {P\,dV}{T}}=\int _{V_{\text{i}}}^{V_{\text{f}}}{\frac {nR\,dV}{V}}=nR\ln {\frac {V_{\text{f}}}{V_{\text{i}}}}=Nk_{\text{B}}\ln {\frac {V_{\text{f}}}{V_{\text{i}}}}.}
For an ideal monatomic gas , the entropy as a function of the internal energy U , volume V , and number of moles n is given by the Sackur–Tetrode equation : [ 11 ] S = n R ln [ V N ( 4 π m 3 h 2 U N ) 3 / 2 ] + 5 2 n R . {\displaystyle S=nR\ln \left[{\frac {V}{N}}\left({\frac {4\pi m}{3h^{2}}}{\frac {U}{N}}\right)^{3/2}\right]+{\frac {5}{2}}nR.}
In this expression m is the particle mass and h is the Planck constant. For a monatomic ideal gas U = 3 / 2 nRT = nC V T , with C V the molar heat capacity at constant volume.
A second way to evaluate the entropy change is to choose a route from the initial state to the final state where all the intermediate states are in equilibrium. Such a route can only be realized in the limit where the changes happen infinitely slowly. Such routes are also referred to as quasistatic routes. In some books one demands that a quasistatic route has to be reversible, here we don't add this extra condition. The net entropy change from the initial state to the final state is independent of the particular choice of the quasistatic route, as the entropy is a function of state.
Here is how we can effect the quasistatic route. Instead of letting the gas undergo a free expansion in which the volume is doubled, a free expansion is allowed in which the volume expands by a very small amount δV . After thermal equilibrium is reached, we then let the gas undergo another free expansion by δV and wait until thermal equilibrium is reached. We repeat this until the volume has been doubled. In the limit δV to zero, this becomes an ideal quasistatic process, albeit an irreversible one. Now, according to the fundamental thermodynamic relation , we have: d U = T d S − P d V . {\displaystyle \mathrm {d} U=T\,\mathrm {d} S-P\,\mathrm {d} V.}
As this equation relates changes in thermodynamic state variables, it is valid for any quasistatic change, regardless of whether it is irreversible or reversible. For the above defined path we have that d U = 0 and thus T d S = P d V , and hence the increase in entropy for the Joule expansion is Δ S = ∫ i f d S = ∫ V 0 2 V 0 P d V T = ∫ V 0 2 V 0 n R d V V = n R ln 2. {\displaystyle \Delta S=\int _{i}^{f}\mathrm {d} S=\int _{V_{0}}^{2V_{0}}{\frac {P\,\mathrm {d} V}{T}}=\int _{V_{0}}^{2V_{0}}{\frac {nR\,\mathrm {d} V}{V}}=nR\ln 2.}
A third way to compute the entropy change involves a route consisting of reversible adiabatic expansion followed by heating. We first let the system undergo a reversible adiabatic expansion in which the volume is doubled. During the expansion, the system performs work and the gas temperature goes down, so we have to supply heat to the system equal to the work performed to bring it to the same final state as in case of Joule expansion.
During the reversible adiabatic expansion , we have d S = 0 . From the classical expression for the entropy it can be derived that the temperature after the doubling of the volume at constant entropy is given as: T = T i 2 − R / C V = T i 2 − 2 / 3 {\displaystyle T=T_{i}2^{-R/C_{V}}=T_{i}2^{-2/3}} for the monoatomic ideal gas. Heating the gas up to the initial temperature T i increases the entropy by the amount Δ S = n ∫ T T i C V d T ′ T ′ = n R ln 2. {\displaystyle \Delta S=n\int _{T}^{T_{i}}C_{\mathrm {V} }{\frac {\mathrm {d} T'}{T'}}=nR\ln 2.}
We might ask what the work would be if, once the Joule expansion has occurred, the gas is put back into the left-hand side by compressing it. The best method (i.e. the method involving the least work) is that of a reversible isothermal compression, which would take work W given by W = − ∫ 2 V 0 V 0 P d V = − ∫ 2 V 0 V 0 n R T V d V = n R T ln 2 = T Δ S gas . {\displaystyle W=-\int _{2V_{0}}^{V_{0}}P\,\mathrm {d} V=-\int _{2V_{0}}^{V_{0}}{\frac {nRT}{V}}\mathrm {d} V=nRT\ln 2=T\Delta S_{\text{gas}}.}
During the Joule expansion the surroundings do not change, i.e. the entropy of the surroundings is constant. Therefore the entropy change of the so-called "universe" is equal to the entropy change of the gas which is nR ln 2 .
Joule performed his experiment with air at room temperature which was expanded from a pressure of about 22 bar. Under these conditions, air behaves only approximately as an ideal gas. As a result, the real temperature change will not be exactly zero. Rather, one can calculate that the temperature of the air should drop by about 3 degrees Celsius when the volume is doubled under adiabatic conditions. [ 12 ] However, due to the low heat capacity of the air and the high heat capacity of the strong copper containers and the water of the calorimeter, the observed temperature drop is much smaller, so Joule found that the temperature change was zero within his measuring accuracy.
The majority of good undergraduate textbooks deal with this expansion in great depth; see e.g. Concepts in Thermal Physics , Blundell & Blundell, OUP ISBN 0-19-856770-7 | https://en.wikipedia.org/wiki/Joule_expansion |
Joule heating (also known as resistive heating , resistance heating , or Ohmic heating ) is the process by which the passage of an electric current through a conductor produces heat .
Joule's first law (also just Joule's law ), also known in countries of the former USSR as the Joule–Lenz law , [ 1 ] states that the power of heating generated by an electrical conductor equals the product of its resistance and the square of the current. Joule heating affects the whole electric conductor, unlike the Peltier effect which transfers heat from one electrical junction to another.
Joule-heating or resistive-heating is used in many devices and industrial processes. The part that converts electricity into heat is called a heating element .
Practical applications of joule heating include but not limited to:
James Prescott Joule first published in December 1840, an abstract in the Proceedings of the Royal Society , suggesting that heat could be generated by an electrical current. Joule immersed a length of wire in a fixed mass of water and measured the temperature rise due to a known current flowing through the wire for a 30 minute period. By varying the current and the length of the wire he deduced that the heat produced was proportional to the square of the current multiplied by the electrical resistance of the immersed wire. [ 5 ]
In 1841 and 1842, subsequent experiments showed that the amount of heat generated was proportional to the chemical energy used in the voltaic pile that generated the template. This led Joule to reject the caloric theory (at that time the dominant theory) in favor of the mechanical theory of heat (according to which heat is another form of energy ). [ 5 ]
Resistive heating was independently studied by Heinrich Lenz in 1842. [ 1 ]
The SI unit of energy was subsequently named the joule and given the symbol J . The commonly known unit of power, the watt , is equivalent to one joule per second.
Joule heating is caused by interactions between charge carriers (usually electrons ) and the body of the conductor.
A potential difference ( voltage ) between two points of a conductor creates an electric field that accelerates charge carriers in the direction of the electric field, giving them kinetic energy . When the charged particles collide with the quasi-particles in the conductor (i.e. the canonically quantized, ionic lattice oscillations in the harmonic approximation of a crystal), energy is being transferred from the electrons to the lattice (by the creation of further lattice oscillations). The oscillations of the ions are the origin of the radiation (" thermal energy ") that one measures in a typical experiment.
Joule heating is referred to as ohmic heating or resistive heating because of its relationship to Ohm's Law . It forms the basis for the large number of practical applications involving electric heating . However, in applications where heating is an unwanted by-product of current use (e.g., load losses in electrical transformers ) the diversion of energy is often referred to as resistive loss . The use of high voltages in electric power transmission systems is specifically designed to reduce such losses in cabling by operating with commensurately lower currents. The ring circuits , or ring mains, used in UK homes are another example, where power is delivered to outlets at lower currents (per wire, by using two paths in parallel), thus reducing Joule heating in the wires. Joule heating does not occur in superconducting materials, as these materials have zero electrical resistance in the superconducting state.
Resistors create electrical noise, called Johnson–Nyquist noise . There is an intimate relationship between Johnson–Nyquist noise and Joule heating, explained by the fluctuation-dissipation theorem .
The most fundamental formula for Joule heating is the generalized power equation: P = I ( V A − V B ) {\displaystyle P=I(V_{A}-V_{B})} where
The explanation of this formula ( P = I V {\displaystyle P=IV} ) is: [ 6 ]
Assuming the element behaves as a perfect resistor and that the power is completely converted into heat, the formula can be re-written by substituting Ohm's law , V = I R {\displaystyle V=IR} , into the generalized power equation: P = I V = I 2 R = V 2 / R {\displaystyle P=IV=I^{2}R=V^{2}/R} where R is the resistance .
Voltage can be increased in DC circuits by connecting batteries or solar panels in series.
When current varies, as it does in AC circuits,
P ( t ) = U ( t ) I ( t ) {\displaystyle P(t)=U(t)I(t)}
where t is time and P is the instantaneous active power being converted from electrical energy to heat. Far more often, the average power is of more interest than the instantaneous power:
P a v g = U rms I rms = ( I rms ) 2 R = ( U rms ) 2 / R {\displaystyle P_{\rm {avg}}=U_{\text{rms}}I_{\text{rms}}=(I_{\text{rms}})^{2}R=(U_{\text{rms}})^{2}/R}
where "avg" denotes average (mean) over one or more cycles, and "rms" denotes root mean square .
These formulas are valid for an ideal resistor, with zero reactance . If the reactance is nonzero, the formulas are modified:
P a v g = U rms I rms cos ϕ = ( I rms ) 2 Re ( Z ) = ( U rms ) 2 Re ( Y ∗ ) {\displaystyle P_{\rm {avg}}=U_{\text{rms}}I_{\text{rms}}\cos \phi =(I_{\text{rms}})^{2}\operatorname {Re} (Z)=(U_{\text{rms}})^{2}\operatorname {Re} (Y^{*})}
where ϕ {\displaystyle \phi } is phase difference between current and voltage, Re {\displaystyle \operatorname {Re} } means real part , Z is the complex impedance , and Y* is the complex conjugate of the admittance (equal to 1/ Z* ).
For more details in the reactive case, see AC power .
Joule heating can also be calculated at a particular location in space. The differential form of the Joule heating equation gives the power per unit volume.
d P d V = J ⋅ E {\displaystyle {\frac {\mathrm {d} P}{\mathrm {d} V}}=\mathbf {J} \cdot \mathbf {E} }
Here, J {\displaystyle \mathbf {J} } is the current density, and E {\displaystyle \mathbf {E} } is the electric field. For a material with a conductivity σ {\displaystyle \sigma } , J = σ E {\displaystyle \mathbf {J} =\sigma \mathbf {E} } and therefore d P d V = J ⋅ E = J ⋅ J 1 σ = J 2 ρ {\displaystyle {\frac {\mathrm {d} P}{\mathrm {d} V}}=\mathbf {J} \cdot \mathbf {E} =\mathbf {J} \cdot \mathbf {J} {\frac {1}{\sigma }}=J^{2}\rho }
where ρ = 1 / σ {\displaystyle \rho =1/\sigma } is the resistivity . This directly resembles the " I 2 R {\displaystyle I^{2}R} " term of the macroscopic form.
In the harmonic case, where all field quantities vary with the angular frequency ω {\displaystyle \omega } as e − i ω t {\displaystyle e^{-\mathrm {i} \omega t}} , complex valued phasors J ^ {\displaystyle {\hat {\mathbf {J} }}} and E ^ {\displaystyle {\hat {\mathbf {E} }}} are usually introduced for the current density and the electric field intensity, respectively. The Joule heating then reads d P d V = 1 2 J ^ ⋅ E ^ ∗ = 1 2 J ^ ⋅ J ^ ∗ / σ = 1 2 J 2 ρ , {\displaystyle {\frac {\mathrm {d} P}{\mathrm {d} V}}={\frac {1}{2}}{\hat {\mathbf {J} }}\cdot {\hat {\mathbf {E} }}^{*}={\frac {1}{2}}{\hat {\mathbf {J} }}\cdot {\hat {\mathbf {J} }}^{*}/\sigma ={\frac {1}{2}}J^{2}\rho ,} where ∙ ∗ {\displaystyle \bullet ^{*}} denotes the complex conjugate .
Overhead power lines transfer electrical energy from electricity producers to consumers. Those power lines have a nonzero resistance and therefore are subject to Joule heating, which causes transmission losses.
The split of power between transmission losses (Joule heating in transmission lines) and load (useful energy delivered to the consumer) can be approximated by a voltage divider . In order to minimize transmission losses, the resistance of the lines has to be as small as possible compared to the load (resistance of consumer appliances). Line resistance is minimized by the use of copper conductors , but the resistance and power supply specifications of consumer appliances are fixed.
Usually, a transformer is placed between the lines and consumption. When a high-voltage, low-intensity current in the primary circuit (before the transformer) is converted into a low-voltage, high-intensity current in the secondary circuit (after the transformer), the equivalent resistance of the secondary circuit becomes higher [ 7 ] and transmission losses are reduced in proportion.
During the war of currents , AC installations could use transformers to reduce line losses by Joule heating, at the cost of higher voltage in the transmission lines, compared to DC installations.
Joule heating is a flash pasteurization (also called "high-temperature short-time" (HTST)) aseptic process that runs an alternating current of 50–60 Hz through food. [ 8 ] Heat is generated through the food's electrical resistance. [ 8 ] [ 9 ] [ 10 ] [ 11 ] As the product heats, electrical conductivity increases linearly. [ 3 ] A higher electrical current frequency is best as it reduces oxidation and metallic contamination. [ 8 ] This heating method is best for foods that contain particulates suspended in a weak salt-containing medium due to their high resistance properties. [ 4 ] [ 8 ]
Heat is generated rapidly and uniformly in the liquid matrix as well as in particulates , producing a higher quality sterile product that is suitable for aseptic processing . [ 11 ] [ 12 ]
Electrical energy is linearly translated to thermal energy as electrical conductivity increases, and this is the key process parameter that affects heating uniformity and heating rate. [ 11 ] This heating method is best for foods that contain particulates suspended in a weak salt containing medium due to their high resistance properties. [ 10 ] Ohmic heating is beneficial due to its ability to inactivate microorganisms through thermal and non-thermal cellular damage. [ 11 ] [ 13 ] [ 14 ]
This method can also inactivate antinutritional factors thereby maintaining nutritional and sensory properties . [ 13 ] However, ohmic heating is limited by viscosity , electrical conductivity, and fouling deposits. [ 9 ] [ 10 ] [ 11 ] Although ohmic heating has not yet been approved by the Food and Drug Administration ( FDA ) for commercial use, this method has many potential applications, ranging from cooking to fermentation . [ 11 ]
There are different configurations for continuous ohmic heating systems, but in the most basic process, [ 11 ] a power supply or generator is needed to produce electrical current. [ 10 ] Electrodes , in direct contact with food, pass electric current through the matrix. [ 10 ] The distance between the electrodes can be adjusted to achieve the optimum electrical field strength. [ 10 ]
The generator creates the electrical current which flows to the first electrode and passes through the food product placed in the electrode gap. [ 10 ] The food product resists the flow of current causing internal heating. [ 11 ] The current continues to flow to the second electrode and back to the power source to close the circuit. [ 10 ] The insulator caps around the electrodes controls the environment within the system. [ 10 ]
The electrical field strength and the residence time are the key process parameters which affect heat generation. [ 11 ]
The ideal foods for ohmic heating are viscous with particulates. [ 11 ]
The efficiency by which electricity is converted to heat depends upon on salt, water, and fat content due to their thermal conductivity and resistance factors. [ 13 ] In particulate foods, the particles heat up faster than the liquid matrix due to higher resistance to electricity and matching conductivity can contribute to uniform heating. [ 11 ] This prevents overheating of the liquid matrix while particles receive sufficient heat processing. [ 9 ] Table 1 shows the electrical conductivity values of certain foods to display the effect of composition and salt concentration. [ 11 ] The high electrical conductivity values represent a larger number of ionic compounds suspended in the product, which is directly proportional to the rate of heating. [ 10 ] This value is increased in the presence of polar compounds , like acids and salts, but decreased with nonpolar compounds , like fats. [ 10 ] Electrical conductivity of food materials generally increases with temperature, and can change if there are structural changes caused during heating such as gelatinization of starch. [ 11 ] Density, pH, and specific heat of various components in a food matrix can also influence heating rate. [ 13 ]
Benefits of Ohmic heating include: uniform and rapid heating (>1°Cs −1 ), less cooking time, better energy efficiency , lower capital cost, and heating simulataneously throughout food's volume as compared to aseptic processing , canning , and PEF . [ 12 ] Volumetric heating allows internal heating instead of transferring heat from a secondary medium. [ 9 ] This results in the production of safe, high quality food with minimal changes to structural, nutritional, and organoleptic properties of food. [ 9 ] Heat transfer is uniform to reach areas of food that are harder to heat. [ 11 ] Less fouling accumulates on the electrodes as compared to other heating methods. [ 10 ] Ohmic heating also requires less cleaning and maintenance, resulting in an environmentally cautious heating method. [ 9 ] [ 11 ] [ 12 ]
Microbial inactivation in ohmic heating is achieved by both thermal and non-thermal cellular damage from the electrical field. [ 14 ] This method destroys microorganisms due to electroporation of cell membranes , physical membrane rupture, and cell lysis . [ 11 ] [ 13 ] In electroporation, excessive leakage of ions and intramolecular components results in cell death. [ 13 ] In membrane rupture, cells swell due to an increase in moisture diffusion across the cell membrane. [ 12 ] Pronounced disruption and decomposition of cell walls and cytoplasmic membranes causes cells to lyse. [ 11 ] [ 13 ] [ 14 ]
Decreased processing times in ohmic heating maintains nutritional and sensory properties of foods. [ 9 ] Ohmic heating inactivates antinutritional factors like lipoxigenase (LOX), polyphenoloxidase (PPO), and pectinase due to the removal of active metallic groups in enzymes by the electrical field. [ 13 ] Similar to other heating methods, ohmic heating causes gelatinization of starches, melting of fats, and protein agglutination . [ 11 ] Water-soluble nutrients are maintained in the suspension liquid allowing for no loss of nutritional value if the liquid is consumed. [ 15 ]
Ohmic heating is limited by viscosity, electrical conductivity, and fouling deposits. [ 9 ] [ 10 ] [ 11 ] The density of particles within the suspension liquid can limit the degree of processing. A higher viscosity fluid will provide more resistance to heating, allowing the mixture to heat up quicker than low viscosity products. [ 11 ] A food product's electrical conductivity is a function of temperature, frequency, and product composition. [ 9 ] [ 10 ] [ 11 ] This may be increased by adding ionic compounds, or decreased by adding non-polar constituents. [ 9 ] Changes in electrical conductivity limit ohmic heating as it is difficult to model the thermal process when temperature increases in multi-component foods. [ 9 ] [ 10 ]
The potential applications of ohmic heating range from cooking, thawing, blanching , peeling, evaporation, extraction, dehydration , and fermentation. [ 11 ] These allow for ohmic heating to pasteurize particulate foods for hot filling, pre-heat products prior to canning, and aseptically process ready-to-eat meals and refrigerated foods. [ 10 ] Prospective examples are outlined in Table 2 as this food processing method has not been commercially approved by the FDA. [ 10 ] Since there is currently insufficient data on electrical conductivities for solid foods, it is difficult to prove the high quality and safe process design for ohmic heating. [ 16 ] Additionally, a successful 12D reduction for C. botulinum prevention has yet to be validated. [ 16 ]
Flash joule heating (transient high-temperature electrothermal heating) has been used to synthesize allotropes of carbon , including graphene and diamond. Heating various solid carbon feedstocks (carbon black, coal, coffee grounds, etc.) to temperatures of ~3000 K for 10-150 milliseconds produces turbostratic graphene flakes . [ 17 ] FJH has also been used to recover rare-earth elements used in modern electronics from industrial wastes . [ 18 ] [ 19 ] Beginning from a fluorinated carbon source, fluorinated activated carbon, fluorinated nanodiamond , concentric carbon (carbon shell around a nanodiamond core), and fluorinated flash graphene can be synthesized. [ 20 ] [ 21 ]
Heat is not to be confused with internal energy or synonymously thermal energy . While intimately connected to heat , they are distinct physical quantities.
As a heating technology, Joule heating has a coefficient of performance of 1.0, meaning that every joule of electrical energy supplied produces one joule of heat. In contrast, a heat pump can have a coefficient of more than 1.0 since it moves additional thermal energy from the environment to the heated item.
The definition of the efficiency of a heating process requires defining the boundaries of the system to be considered. When heating a building, the overall efficiency is different when considering heating effect per unit of electric energy delivered on the customer's side of the meter, compared to the overall efficiency when also considering the losses in the power plant and transmission of power.
In the energy balance of groundwater flow a hydraulic equivalent of Joule's law is used: [ 22 ]
d E d x = ( v x ) 2 K {\displaystyle {\frac {dE}{dx}}={\frac {(v_{x})^{2}}{K}}}
where: | https://en.wikipedia.org/wiki/Joule_heating |
The joule per mole (symbol: J·mol −1 or J/mol) is the unit of energy per amount of substance in the International System of Units (SI), such that energy is measured in joules , and the amount of substance is measured in moles .
It is also an SI derived unit of molar thermodynamic energy defined as the energy equal to one joule in one mole of substance. [ 1 ] [ 2 ] For example, the Gibbs free energy of a compound in the area of thermochemistry is often quantified in units of kilojoules per mole (symbol: kJ·mol −1 or kJ/mol), with 1 kilojoule = 1000 joules. [ 3 ]
Physical quantities measured in J·mol −1 usually describe quantities of energy transferred during phase transformations or chemical reactions . Division by the number of moles facilitates comparison between processes involving different quantities of material and between similar processes involving different types of materials. The precise meaning of such a quantity is dependent on the context (what substances are involved, circumstances, etc.), but the unit of measurement is used specifically to describe certain existing phenomena, such as in thermodynamics it is the unit of measurement that describes molar energy. [ 4 ]
Since there are 6.02214076 × 10 23 particles (atoms, molecules, ions etc.) per mole, 1 joule per mole is equal to 1 joule multiplied by 6.02214076 × 10 23 particles. Because of the typical order of magnitude for energy changes in chemical processes, kJ·mol −1 is normally used instead of J·mol −1 . For example, heats of fusion and vaporization are usually of the order of 10 kJ·mol −1 , bond energies are of the order of 100 kJ·mol −1 , and ionization energies of the order of 1000 kJ·mol −1 . [ 5 ] For this reason, it is common within the field of chemistry to quantify the enthalpy of reaction in units of kJ·mol −1 . [ 6 ]
Other units sometimes used to describe reaction energetics are kilocalories per mole (kcal·mol −1 ), electron volts per particle (eV), and wavenumbers in inverse centimeters (cm −1 ). 1 kJ·mol −1 is approximately equal to 1.04 × 10 −2 eV per particle, 0.239 kcal·mol −1 , or 83.6 cm −1 . At room temperature (25 °C , or 298.15 K ) 1 kJ·mol −1 is approximately equal to 0.4034 k B T {\displaystyle k_{B}T} . | https://en.wikipedia.org/wiki/Joule_per_mole |
In thermodynamics , the Joule–Thomson effect (also known as the Joule–Kelvin effect or Kelvin–Joule effect ) describes the temperature change of a real gas or liquid (as differentiated from an ideal gas ) when it is expanding; typically caused by the pressure loss from flow through a valve or porous plug while keeping it insulated so that no heat is exchanged with the environment. [ 1 ] [ 2 ] [ 3 ] This procedure is called a throttling process or Joule–Thomson process . [ 4 ] The effect is purely due to deviation from ideality, as any ideal gas has no JT effect.
At room temperature, all gases except hydrogen , helium , and neon cool upon expansion by the Joule–Thomson process when being throttled through an orifice; these three gases rise in temperature when forced through a porous plug at room temperature, but lowers in temperature when already at lower temperatures. [ 5 ] [ 6 ] Most liquids such as hydraulic oils will be warmed by the Joule–Thomson throttling process. The temperature at which the JT effect switches sign is the inversion temperature .
The gas-cooling throttling process is commonly exploited in refrigeration processes such as liquefiers in air separation industrial process. [ 7 ] [ 8 ] In hydraulics, the warming effect from Joule–Thomson throttling can be used to find internally leaking valves as these will produce heat which can be detected by thermocouple or thermal-imaging camera . Throttling is a fundamentally irreversible process . The throttling due to the flow resistance in supply lines, heat exchangers, regenerators, and other components of (thermal) machines is a source of losses that limits their performance.
Since it is a constant-enthalpy process, it can be used to experimentally measure the lines of constant enthalpy (isenthalps) on the ( p , T ) {\displaystyle (p,T)} diagram of a gas. Combined with the specific heat capacity at constant pressure c P = ( ∂ h / ∂ T ) P {\displaystyle c_{P}=(\partial h/\partial T)_{P}} it allows the complete measurement of the thermodynamic potential for the gas. [ 9 ]
The effect is named after James Prescott Joule and William Thomson, 1st Baron Kelvin , who discovered it in 1852. It followed upon earlier work by Joule on Joule expansion , in which a gas undergoes free expansion in a vacuum and the temperature is unchanged, if the gas is ideal .
The adiabatic (no heat exchanged) expansion of a gas may be carried out in a number of ways. The change in temperature experienced by the gas during expansion depends not only on the initial and final pressure, but also on the manner in which the expansion is carried out.
The temperature change produced during a Joule–Thomson expansion is quantified by the Joule–Thomson coefficient , μ J T {\displaystyle \mu _{\mathrm {JT} }} . This coefficient may be either positive (corresponding to cooling) or negative (heating); the regions where each occurs for molecular nitrogen, N 2 , are shown in the figure. Note that most conditions in the figure correspond to N 2 being a supercritical fluid , where it has some properties of a gas and some of a liquid, but can not be really described as being either. The coefficient is negative at both very high and very low temperatures; at very high pressure it is negative at all temperatures. The maximum inversion temperature (621 K for N 2 [ 11 ] ) occurs as zero pressure is approached. For N 2 gas at low pressures, μ J T {\displaystyle \mu _{\mathrm {JT} }} is negative at high temperatures and positive at low temperatures. At temperatures below the gas-liquid coexistence curve , N 2 condenses to form a liquid and the coefficient again becomes negative. Thus, for N 2 gas below 621 K, a Joule–Thomson expansion can be used to cool the gas until liquid N 2 forms.
There are two factors that can change the temperature of a fluid during an adiabatic expansion: a change in internal energy or the conversion between potential and kinetic internal energy. Temperature is the measure of thermal kinetic energy (energy associated with molecular motion); so a change in temperature indicates a change in thermal kinetic energy. The internal energy is the sum of thermal kinetic energy and thermal potential energy. [ 12 ] Thus, even if the internal energy does not change, the temperature can change due to conversion between kinetic and potential energy; this is what happens in a free expansion and typically produces a decrease in temperature as the fluid expands. [ 13 ] [ 14 ] If work is done on or by the fluid as it expands, then the total internal energy changes. This is what happens in a Joule–Thomson expansion and can produce larger heating or cooling than observed in a free expansion.
In a Joule–Thomson expansion the enthalpy remains constant. The enthalpy, H {\displaystyle H} , is defined as
where U {\displaystyle U} is internal energy, P {\displaystyle P} is pressure, and V {\displaystyle V} is volume. Under the conditions of a Joule–Thomson expansion, the change in P V {\displaystyle PV} represents the work done by the fluid (see the proof below). If P V {\displaystyle PV} increases, with H {\displaystyle H} constant, then U {\displaystyle U} must decrease as a result of the fluid doing work on its surroundings. This produces a decrease in temperature and results in a positive Joule–Thomson coefficient. Conversely, a decrease in P V {\displaystyle PV} means that work is done on the fluid and the internal energy increases. If the increase in kinetic energy exceeds the increase in potential energy, there will be an increase in the temperature of the fluid and the Joule–Thomson coefficient will be negative.
For an ideal gas, P V {\displaystyle PV} does not change during a Joule–Thomson expansion. [ 15 ] As a result, there is no change in internal energy; since there is also no change in thermal potential energy, there can be no change in thermal kinetic energy and, therefore, no change in temperature. In real gases, P V {\displaystyle PV} does change.
The ratio of the value of P V {\displaystyle PV} to that expected for an ideal gas at the same temperature is called the compressibility factor , Z {\displaystyle Z} . For a gas, this is typically less than unity at low temperature and greater than unity at high temperature (see the discussion in compressibility factor ). At low pressure, the value of Z {\displaystyle Z} always moves towards unity as a gas expands. [ 16 ] Thus at low temperature, Z {\displaystyle Z} and P V {\displaystyle PV} will increase as the gas expands, resulting in a positive Joule–Thomson coefficient. At high temperature, Z {\displaystyle Z} and P V {\displaystyle PV} decrease as the gas expands; if the decrease is large enough, the Joule–Thomson coefficient will be negative.
For liquids, and for supercritical fluids under high pressure, P V {\displaystyle PV} increases as pressure increases. [ 16 ] This is due to molecules being forced together, so that the volume can barely decrease due to higher pressure. Under such conditions, the Joule–Thomson coefficient is negative, as seen in the figure above .
The physical mechanism associated with the Joule–Thomson effect is closely related to that of a shock wave , [ 17 ] although a shock wave differs in that the change in bulk kinetic energy of the gas flow is not negligible.
The rate of change of temperature T {\displaystyle T} with respect to pressure P {\displaystyle P} in a Joule–Thomson process (that is, at constant enthalpy H {\displaystyle H} ) is the Joule–Thomson (Kelvin) coefficient μ J T {\displaystyle \mu _{\mathrm {JT} }} . This coefficient can be expressed in terms of the gas's specific volume V {\displaystyle V} , its heat capacity at constant pressure C p {\displaystyle C_{\mathrm {p} }} , and its coefficient of thermal expansion α {\displaystyle \alpha } as: [ 1 ] [ 3 ] [ 18 ]
See the § Derivation of the Joule–Thomson coefficient below for the proof of this relation. The value of μ J T {\displaystyle \mu _{\mathrm {JT} }} is typically expressed in °C/ bar (SI units: K / Pa ) and depends on the type of gas and on the temperature and pressure of the gas before expansion. Its pressure dependence is usually only a few percent for pressures up to 100 bar.
All real gases have an inversion point at which the value of μ J T {\displaystyle \mu _{\mathrm {JT} }} changes sign. The temperature of this point, the Joule–Thomson inversion temperature , depends on the pressure of the gas before expansion.
In a gas expansion the pressure decreases, so the sign of ∂ P {\displaystyle \partial P} is negative by definition. With that in mind, the following table explains when the Joule–Thomson effect cools or warms a real gas:
Helium and hydrogen are two gases whose Joule–Thomson inversion temperatures at a pressure of one atmosphere are very low (e.g., about 40 K, −233 °C for helium). Thus, helium and hydrogen warm when expanded at constant enthalpy at typical room temperatures. On the other hand, nitrogen and oxygen , the two most abundant gases in air, have inversion temperatures of 621 K (348 °C) and 764 K (491 °C) respectively: these gases can be cooled from room temperature by the Joule–Thomson effect. [ 1 ] [ 11 ]
For an ideal gas, μ JT {\displaystyle \mu _{\text{JT}}} is always equal to zero: ideal gases neither warm nor cool upon being expanded at constant enthalpy.
For a Van der Waals gas , the coefficient is [ 19 ] μ JT = − V m C p R T V m 2 b − 2 a ( V m − b ) 2 R T V m 3 − 2 a ( V m − b ) 2 . {\displaystyle \mu _{\text{JT}}=-{\frac {V_{m}}{C_{p}}}{\frac {RTV_{m}^{2}b-2a(V_{m}-b)^{2}}{RTV_{m}^{3}-2a(V_{m}-b)^{2}}}.} with inversion temperature 2 a b R ( 1 − b V m ) 2 {\displaystyle {\frac {2a}{bR}}\left(1-{\frac {b}{V_{m}}}\right)^{2}} .
For the Dieterici gas , the reduced inversion temperature is T ~ I = 8 − 4 / V ~ m {\displaystyle {\tilde {T}}_{I}=8-4/{\tilde {V}}_{m}} , and the relation between reduced pressure and reduced inversion temperature is p ~ = ( 8 − T ~ I ) e 5 2 − 4 8 − T ~ I {\displaystyle {\tilde {p}}=(8-{\tilde {T}}_{I})e^{{\frac {5}{2}}-{\frac {4}{8-{\tilde {T}}_{I}}}}} . This is plotted on the right. The critical point falls inside the region where the gas cools on expansion. The outside region is where the gas warms on expansion. [ 9 ]
In practice, the Joule–Thomson effect is achieved by allowing the gas to expand through a throttling device (usually a valve ) which must be very well insulated to prevent any heat transfer to or from the gas. No external work is extracted from the gas during the expansion (the gas must not be expanded through a turbine , for example).
The cooling produced in the Joule–Thomson expansion makes it a valuable tool in refrigeration . [ 8 ] [ 20 ] The effect is applied in the Linde technique as a standard process in the petrochemical industry , where the cooling effect is used to liquefy gases , and in many cryogenic applications (e.g. for the production of liquid oxygen, nitrogen, and argon ). A gas must be below its inversion temperature to be liquefied by the Linde cycle. For this reason, simple Linde cycle liquefiers, starting from ambient temperature, cannot be used to liquefy helium, hydrogen, or neon . They must first be cooled to their inversion temperatures, which are −233 °C (helium), −71 °C (hydrogen), and −42 °C (neon). [ 11 ]
In thermodynamics so-called "specific" quantities are quantities per unit mass (kg) and are denoted by lower-case characters. So h , u , and v are the specific enthalpy , specific internal energy, and specific volume (volume per unit mass, or reciprocal density), respectively. In a Joule–Thomson process the specific enthalpy h remains constant. [ 21 ] To prove this, the first step is to compute the net work done when a mass m of the gas moves through the plug. This amount of gas has a volume of V 1 = m v 1 in the region at pressure P 1 (region 1) and a volume V 2 = m v 2 when in the region at pressure P 2 (region 2). Then in region 1, the "flow work" done on the amount of gas by the rest of the gas is: W 1 = m P 1 v 1 . In region 2, the work done by the amount of gas on the rest of the gas is: W 2 = m P 2 v 2 . So, the total work done on the mass m of gas is
The change in internal energy minus the total work done on the amount of gas is, by the first law of thermodynamics , the total heat supplied to the amount of gas.
In the Joule–Thomson process, the gas is insulated, so no heat is absorbed. This means that
where u 1 and u 2 denote the specific internal energies of the gas in regions 1 and 2, respectively. Using the definition of the specific enthalpy h = u + Pv , the above equation implies that
where h 1 and h 2 denote the specific enthalpies of the amount of gas in regions 1 and 2, respectively.
A convenient way to get a quantitative understanding of the throttling process is by using diagrams such as h - T diagrams, h - P diagrams, and others. Commonly used are the so-called T - s diagrams. Figure 2 shows the T - s diagram of nitrogen as an example. [ 22 ] Various points are indicated as follows:
As shown before, throttling keeps h constant. E.g. throttling from 200 bar and 300 K (point a in fig. 2) follows the isenthalpic (line of constant specific enthalpy) of 430 kJ/kg. At 1 bar it results in point b which has a temperature of 270 K. So throttling from 200 bar to 1 bar gives a cooling from room temperature to below the freezing point of water. Throttling from 200 bar and an initial temperature of 133 K (point c in fig. 2) to 1 bar results in point d, which is in the two-phase region of nitrogen at a temperature of 77.2 K. Since the enthalpy is an extensive parameter the enthalpy in d ( h d ) is equal to the enthalpy in e ( h e ) multiplied with the mass fraction of the liquid in d ( x d ) plus the enthalpy in f ( h f ) multiplied with the mass fraction of the gas in d (1 − x d ). So
With numbers: 150 = x d 28 + (1 − x d ) 230 so x d is about 0.40. This means that the mass fraction of the liquid in the liquid–gas mixture leaving the throttling valve is 40%.
It is difficult to think physically about what the Joule–Thomson coefficient, μ J T {\displaystyle \mu _{\mathrm {JT} }} , represents. Also, modern determinations of μ J T {\displaystyle \mu _{\mathrm {JT} }} do not use the original method used by Joule and Thomson, but instead measure a different, closely related quantity. [ 23 ] Thus, it is useful to derive relationships between μ J T {\displaystyle \mu _{\mathrm {JT} }} and other, more conveniently measured quantities, as described below.
The first step in obtaining these results is to note that the Joule–Thomson coefficient involves the three variables T , P , and H . A useful result is immediately obtained by applying the cyclic rule ; in terms of these three variables that rule may be written
Each of the three partial derivatives in this expression has a specific meaning. The first is μ J T {\displaystyle \mu _{\mathrm {JT} }} , the second is the constant pressure heat capacity , C p {\displaystyle C_{\mathrm {p} }} , defined by
and the third is the inverse of the isothermal Joule–Thomson coefficient , μ T {\displaystyle \mu _{\mathrm {T} }} , defined by
This last quantity is more easily measured than μ J T {\displaystyle \mu _{\mathrm {JT} }} . [ 24 ] [ 25 ] Thus, the expression from the cyclic rule becomes
This equation can be used to obtain Joule–Thomson coefficients from the more easily measured isothermal Joule–Thomson coefficient. It is used in the following to obtain a mathematical expression for the Joule–Thomson coefficient in terms of the volumetric properties of a fluid.
To proceed further, the starting point is the fundamental equation of thermodynamics in terms of enthalpy; this is
Now "dividing through" by d P , while holding temperature constant, yields
The partial derivative on the left is the isothermal Joule–Thomson coefficient, μ T {\displaystyle \mu _{\mathrm {T} }} , and the one on the right can be expressed in terms of the coefficient of thermal expansion via a Maxwell relation . The appropriate relation is
where α is the cubic coefficient of thermal expansion . Replacing these two partial derivatives yields
This expression can now replace μ T {\displaystyle \mu _{\mathrm {T} }} in the earlier equation for μ J T {\displaystyle \mu _{\mathrm {JT} }} to obtain:
This provides an expression for the Joule–Thomson coefficient in terms of the commonly available properties heat capacity, molar volume, and thermal expansion coefficient. It shows that the Joule–Thomson inversion temperature, at which μ J T {\displaystyle \mu _{\mathrm {JT} }} is zero, occurs when the coefficient of thermal expansion is equal to the inverse of the temperature. Since this is true at all temperatures for ideal gases (see expansion in gases ), the Joule–Thomson coefficient of an ideal gas is zero at all temperatures. [ 26 ]
It is easy to verify that for an ideal gas defined by suitable microscopic postulates that αT = 1, so the temperature change of such an ideal gas at a Joule–Thomson expansion is zero.
For such an ideal gas, this theoretical result implies that:
This rule was originally found by Joule experimentally for real gases and is known as Joule's second law . More refined experiments found important deviations from it. [ 27 ] [ 28 ] [ 29 ] | https://en.wikipedia.org/wiki/Joule–Thomson_effect |
The Journal of Agricultural and Environmental Ethics is a biannual peer-reviewed academic journal covering agricultural science and bioethics . It was established in 1988 as the Journal of Agricultural Ethics , obtaining its current name in 1991. [ 1 ] The editor-in-chief is Jeffrey Burkhardt ( Institute of Food and Agricultural Sciences ). According to the Journal Citation Reports , the journal has a 2015 impact factor of 1.188, ranking it 19th out of 51 journals in the category "Ethics". [ 2 ]
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The Journal of Agricultural and Food Chemistry is a weekly peer-reviewed scientific journal established in 1953 by the American Chemical Society . [ 1 ] Since 2015, Thomas Hofmann ( Technical University of Munich ) has been the editor-in-chief . [ 2 ]
The journal covers research dealing with the chemistry and biochemistry of agriculture and food including work with chemistry and/or biochemistry as a major component combined with biological/sensory/nutritional/toxicological evaluation related to agriculture and/or food.
The journal is abstracted and indexed in Chemical Abstracts Service , Scopus , ProQuest , PubMed , CABI , and the Science Citation Index Expanded . According to the Journal Citation Reports , the Journal of Agricultural and Food Chemistry has a 2015 impact factor of 4.192. [ 3 ] | https://en.wikipedia.org/wiki/Journal_of_Agricultural_and_Food_Chemistry |
Journal of Algebra (ISSN 0021-8693) is an international mathematical research journal in algebra . An imprint of Academic Press , it is published by Elsevier . Journal of Algebra was founded by Graham Higman , who was its editor from 1964 to 1984. From 1985 until 2000, Walter Feit served as its editor-in-chief.
In 2004, Journal of Algebra announced (vol. 276, no. 1 and 2) the creation of a new section on computational algebra, with a separate editorial board. The first issue completely devoted to computational algebra was vol. 292, no. 1 (October 2005).
The Editor-in-Chief of the Journal of Algebra is Michel Broué , Université Paris Diderot , and Gerhard Hiß, Rheinisch-Westfälische Technische Hochschule Aachen ( RWTH ) is Editor of the computational algebra section.
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The Journal of Algebra and Its Applications covers both theoretical and applied algebra , with a focus on practical applications. It is published by World Scientific . [ 1 ]
According to the Journal Citation Reports , the journal has a 2020 impact factor of 0.736.
The journal is abstracted and indexed in: | https://en.wikipedia.org/wiki/Journal_of_Algebra_and_Its_Applications |
The Journal of Alloys and Compounds is a peer-reviewed scientific journal covering experimental and theoretical approaches to materials problems that involve compounds and alloys . It is published by Elsevier and the editor-in-chief is Hongge Pan, Livio Battezzati. It was the first journal established to focus specifically on a group of inorganic elements. [ 1 ]
The journal was established by William Hume-Rothery in 1958 as the Journal of the Less-Common Metals , [ 2 ] focussing on the chemical elements in the rows of the periodic table for the Actinide and Lanthanide series. The lanthanides are sometimes referred to as the rare earths . [ 1 ] The journal was not strictly limited to articles about those specific elements: it also included papers about the preparation and use of other elements and alloys. [ 2 ]
The journal developed out of an international symposium on metals and alloys above 1200 °C which Hume-Rothery organized at Oxford University on September 17–18, 1958. The conference included more than 100 participants from several countries. The papers presented at the symposium "The study of metals and alloys above 1200°C" were published as volume 1 of the journal. [ 2 ] It was the first journal dealing specifically with a category of inorganic elements. [ 1 ]
The title of "Less-Common Metals" was something of a misnomer , since these metals are actually found fairly commonly, but in small amounts. [ 1 ] [ 3 ] The journal obtained its current name in 1991 [ 4 ] and is considered a particularly rich source of information on hydrogen-metal systems. [ 5 ]
In 2017, Elsevier was reported to be retracting 3 papers from the journal, which was one of several to be affected by falsified reviews, which led to a broader discussion of the processes for reviewing journal articles. [ 6 ] [ 7 ] [ 8 ] [ 9 ]
The journal is abstracted and indexed in:
According to the Journal Citation Reports , the journal has a 2022 impact factor of 6.371. [ 13 ] | https://en.wikipedia.org/wiki/Journal_of_Alloys_and_Compounds |
Journal of Applied Non-Classical Logics is a peer-reviewed academic journal published by Taylor & Francis . It focusses on non-classical logic , in particular
formal aspects (completeness, decidability, complexity), applications to artificial Intelligence and cognitive science ( knowledge representation , automated reasoning , natural language processing ), and theoretical computer science ( program verification , program synthesis ). The journal was established in 1991 by Luis Fariñas del Cerro, who was its editor-in-chief until 2014.
He was succeeded in 2015 by Andreas Herzig.
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The Journal of Bioactive and Compatible Polymers is a bimonthly peer-reviewed scientific journal covering the field of materials science , especially the use of polymers in biomedicine. its editor-in-chief is Kathryn Uhrich ( Rutgers University ). The journal was established in 1986 and is published by SAGE Publications .
The journal is abstracted and indexed in Scopus and the Science Citation Index Expanded . According to the Journal Citation Reports , its 2020 impact factor is 1.756, ranking it 141st out of 160 journals in the category "Biotechnology & Applied Microbiology", [ 1 ] 37th out of 41 journals in the category "Materials Science, Biomaterials", [ 2 ] and 69th out of 91 journals in the category "Polymer Science". [ 3 ] | https://en.wikipedia.org/wiki/Journal_of_Bioactive_and_Compatible_Polymers |
Journal of Biological Inorganic Chemistry (JBIC) is a peer-reviewed scientific journal . It is an official publication of the Society of Biological Inorganic Chemistry [ 1 ] and published by Springer Science+Business Media .
Biological inorganic chemistry is a growing field of science that embraces the principles of biology and inorganic chemistry and impacts other fields ranging from medicine to the environment. JBIC seeks to promote this field internationally. The journal is primarily concerned with advances in understanding the role of metal ions within a biological matrix—be it a protein, DNA/RNA, or a cell, as well as appropriate model studies. Manuscripts describing high-quality original research on the above topics in English are invited for submission to this journal. The journal publishes original articles, minireviews, perspective articles, protocols, and commentaries on debated issues.
Areas of research covered in the journal include: advances in the understanding of systems involving one or more metal ions set in a biological matrix - particularly metalloproteins and metal-nucleic acid complexes - in order to understand biological function at the molecular level. Synthetic analogues mimicking function, structure and spectroscopy of naturally occurring biological molecules are also covered.
The journal is abstracted/indexed in Chemical Abstracts Service , Current Contents /Life Sciences, PubMed / MEDLINE , and the Science Citation Index .
Indexed by ISI Journal of Biological Inorganic Chemistry received an impact factor of 2.538 as reported in the 2014 Journal Citation Reports by Thomson Reuters, ranking it 157 out of 289 journals in the category Biochemistry & Molecular Biology [ 2 ] and ranking it 9th out of 44 journals in the category Chemistry, Inorganic & Nuclear . [ 3 ]
The current editor in chief of JBIC is Nils Metzler-Nolte (Ruhr University Bochum). [ 4 ] [ 5 ] He followed Lawrence Que ( University of Minnesota ) who led the journal from 1999 to 2020 and who succeeded Ivano Bertini (University of Florence) who was the founding editor of JBIC. | https://en.wikipedia.org/wiki/Journal_of_Biological_Inorganic_Chemistry |
The Journal of Biomaterials Applications is a peer-reviewed medical journal covering the development and clinical applications of biomaterials . The editor-in-chief is Jonathan Knowles ( University College London ). The journal was established in 1986 and is published by SAGE Publications .
The journal is abstracted and indexed in: [ 1 ]
According to the Journal Citation Reports , the journal has a 2022 impact factor of 2.9. [ 2 ]
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The Journal of Biomedical Materials Research is a peer-reviewed scientific journals of biomedical material science . It was established in 1967. In 1974, it absorbed Biomedical Materials Symposium (1971–1974). In 1990, it absorbed the journal Journal of Applied Biomaterials (1990–1995). In 2002, it split into two parts, Journal of Biomedical Materials Research Part A , and Journal of Biomedical Materials Research Part B . The two parts are published by John Wiley & Sons .
Journal of Biomedical Materials Research Part A was established in 2003. It is edited by James M. Anderson .
Part A is indexed and abstracted in the following bibliographic databases : [ 1 ] [ 2 ]
According to the Journal Citation Reports , the journal has a 2020 impact factor of 4.396, ranking it 25th out of 90 in the category 'Engineering, Biomedical' [ 3 ] and 18th out of 41 in the category 'Materials Science, Biomaterials. [ 4 ]
The Journal of Biomedical Materials Research Part B: Applied Biomaterials covers design, development, production, and application of biomaterials and medical devices. Publishing formats are original research papers, short reports, reviews, current concepts, special reports, and editorials. It is an official journal of the Society for Biomaterials , the Japanese Society for Biomaterials , the Australasian Society for Biomaterials , and the Korean Society for Biomaterials . The editor-in-chief is Jeremy L. Gilbert ( Syracuse University ).
Part B is indexed and abstracted in the following bibliographic databases: [ 5 ] [ 6 ]
According to the Journal Citation Reports , the journal has a 2020 impact factor of 3.368, ranking it 43rd out of 90 in the category 'Engineering, Biomedical' [ 3 ] and 27th out of 41 in the category 'Materials Science, Biomaterials. [ 4 ] | https://en.wikipedia.org/wiki/Journal_of_Biomedical_Materials_Research |
The Journal of Bioscience and Bioengineering is a monthly peer-reviewed scientific journal . The editor-in-chief is Noriho Kamiya ( Kyushu University ). It is published by The Society for Biotechnology, Japan and distributed outside Japan by Elsevier . It was founded in 1923 as a Japanese-language journal and took its current title in 1999. [ 1 ]
The journal is abstracted and indexed in:
According to the Journal Citation Reports , the journal has a 2017 impact factor of 2.0.15. [ 9 ] | https://en.wikipedia.org/wiki/Journal_of_Bioscience_and_Bioengineering |
The Journal of Cellular Plastics is a bimonthly peer-reviewed scientific journal that covers the field of polymer science and foamed plastics technology. The journal was established in 1965 and is published by SAGE Publications . it was established in 1965 and the editors-in-chief are Chul B. Park ( University of Toronto ).
The journal is abstracted and indexed in:
According to the Journal Citation Reports , the journal has a 2020 impact factor of 3.073. [ 1 ] | https://en.wikipedia.org/wiki/Journal_of_Cellular_Plastics |
The Journal of Chemical & Engineering Data is a peer-reviewed scientific journal , published since 1956 by the American Chemical Society . JCED is currently indexed in: Chemical Abstracts Service (CAS), SCOPUS , EBSCOhost , ProQuest , British Library , PubMed , Ovid , Web of Science , and SwetsWise.
The current Editor is J. Ilja Siepmann. [ 1 ] According to the Journal Citation Reports , the journal has a 2022 impact factor of 2.6. [ 2 ] | https://en.wikipedia.org/wiki/Journal_of_Chemical_&_Engineering_Data |
The Journal of Chemical Ecology is a monthly peer-reviewed scientific journal published by Springer Science+Business Media covering all aspects of chemical ecology . The journal was established in 1975 and is the official journal of the International Society of Chemical Ecologists and the Asia-Pacific Association of Chemical Ecologists . The editor-in-chief is Gary W. Felton ( Pennsylvania State University ). According to the Journal Citation Reports , the journal has a 2013 impact factor of 2.239. [ 1 ]
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The Journal of Chemical Information and Modeling is a peer-reviewed scientific journal published by the American Chemical Society . It was established in 1961 as the Journal of Chemical Documentation , renamed in 1975 to Journal of Chemical Information and Computer Sciences , and obtained its current name in 2005. The journal covers the fields of computational chemistry and chemical informatics . The editor-in-chief is Kenneth M. Merz Jr. ( Michigan State University ). The journal supports Open Science approaches. [ 1 ]
The journal is abstracted and indexed in:
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The Journal of Chemical Theory and Computation is a monthly peer-reviewed scientific journal , established in 2005 by the American Chemical Society . [ 1 ] The editor-in-chief is Laura Gagliardi ( University of Chicago ). [ 2 ] Originally bimonthly, the journal switched to monthly in 2008.
The journal is abstracted and indexed in:
According to the Journal Citation Reports , the journal has a 2023 impact factor of 5.7. [ 8 ] | https://en.wikipedia.org/wiki/Journal_of_Chemical_Theory_and_Computation |
The Journal of Cheminformatics is a peer-reviewed open access scientific journal that covers cheminformatics and molecular modelling . [ 1 ] [ 2 ] It was established in 2009 with David Wild ( Indiana University ) and Christoph Steinbeck (then at EMBL-EBI ) as founding editors-in-chief , and was originally published by Chemistry Central . [ 3 ] At the end of 2015, the Chemistry Central brand was retired and its titles, including Journal of Cheminformatics , were merged with the SpringerOpen portfolio of open access journals. [ 4 ]
As of 2016 [update] , the editors-in-chief are Rajarshi Guha ( National Center for Advancing Translational Sciences ) and Egon Willighagen ( Maastricht University ). [ 5 ] The journal has issued a few special issues ("article collections") in 2011 and 2012, covering topics like PubChem3D , the Resource Description Framework , [ 6 ] and the International Chemical Identifier .
In June 2021 Willighagen announced his intention to step down at the end of the year, explaining in an open letter that the publisher Springer Nature was not sufficiently FAIR and open. [ 7 ] Barbara Zdrazil started as editor in chief in 2022. [ 8 ] [ 9 ]
The journal is abstracted and indexed in:
According to the Journal Citation Reports , the journal has a 2021 impact factor of 8.489. [ 14 ] [ 2 ] The most cited paper is on a cross-platform molecule editor and visualizer called Avogadro , [ 15 ] which has been cited more than 6800 times as of June 2024 according to the Web of Science . [ 16 ] | https://en.wikipedia.org/wiki/Journal_of_Cheminformatics |
The Journal of Chromatography B is a peer-reviewed scientific journal publishing research papers in analytical chemistry , with a focus on chromatography techniques and methods in the biological and life sciences. According to the Journal Citation Reports , Journal of Chromatography B has a 2020 impact factor of 3.205, ranking it 36th out of 83 in the category of Chemistry, Analytical. [ 1 ]
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The Journal of Cleaner Production is a peer-reviewed academic journal covering transdisciplinary research on cleaner production . It is published by Elsevier . The job of editor-in-chief is shared jointly by Cecília Maria Villas Bôas de Almeida ( Paulista University ), and Yutao Wang ( Fudan University ). [ 1 ] The former and founding editor-in-chief was Donald Huisingh ( University of Tennessee ).
The Journal of Cleaner Production serves as a transdisciplinary, international forum for the exchange of information and research concepts, policies, and technologies designed to help ensure progress towards making societies and regions more sustainable. It aims to encourage innovation and creativity, new and improved products, and the implementation of new, cleaner structures, systems, processes, products and services. It is also designed to stimulate the development and implementation of prevention oriented governmental policies and educational programmes.
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The Journal of Coastal Research is a bimonthly peer-reviewed scientific journal covering research on coastal studies and processes. It was established in 1984 as Litoralia , obtaining its current name in 1985. It is published by the Coastal Education and Research Foundation , whose president and executive director, Charles W. Finkl, is also the journal's editor-in-chief . [ 1 ] The journal has been a member of BioOne since 2005. [ 2 ] According to the Journal Citation Reports , the journal has a 2016 impact factor of 0.915, ranking it 193rd out of 229 journals in the category "Environmental Sciences". [ 3 ]
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The Journal of Coatings Technology and Research is a bimonthly peer-reviewed scientific journal . It is owned by the American Coatings Association and published on their behalf by Springer Science+Business Media . The editor-in-chief of the journal is Dr. Mark Nichols ( Ford Motor Company ). [ 1 ]
Areas of research covered in the Journal of Coatings Technology and Research include the manufacture of functional, protective and decorative coatings including paints , inks and related coatings and their raw materials. [ 2 ] The journal publishes research papers describing chemistry , physics , materials science , and engineering studies relevant to surface coatings; Applications papers on experimental solutions for technological problems in the design, formulation, manufacture, application, use and performance of surface coatings ; review articles offering broad, critical overviews of advances in coatings science; and brief communications, presenting notes and letters on research topics of limited scope or immediate impact. [ 2 ]
The journal is abstracted and indexed in: | https://en.wikipedia.org/wiki/Journal_of_Coatings_Technology_and_Research |
The Journal of Colloid and Interface Science is a peer-reviewed scientific journal published by Elsevier . It covers research related to colloid and interface science with a particular focus on colloidal materials and nanomaterials ; surfactants and soft matter ; adsorption , catalysis and electrochemistry ; interfacial processes, capillarity and wetting; biomaterials and nanomedicine ; and novel phenomena and techniques. The editor-in-chief is Martin Malmsten ( Uppsala University ). [ 1 ] The journal was established in 1946 as Journal of Colloid Science . It obtained its current name in 1966.
The journal is abstracted and indexed in:
According to the Journal Citation Reports , the journal has a 2021 Impact Factor of 9.965, ranking it 32nd out of 162 journals in the category "Chemistry, Physical". [ 2 ] | https://en.wikipedia.org/wiki/Journal_of_Colloid_and_Interface_Science |
The Journal of Commutative Algebra is a peer-reviewed academic journal of mathematical research that specializes in commutative algebra and closely related fields. It has been published by the Rocky Mountain Mathematics Consortium (RMMC) since its establishment in 2009. It is currently published four times per year. [ 1 ]
Historically, the Journal of Commutative Algebra filled a niche for the Rocky Mountain Mathematics Consortium when the Canadian Applied Mathematics Quarterly , formerly published by the RMMC, was acquired by the Applied Mathematics Institute of the University of Alberta . Founding editors Jim Coykendall (currently at Clemson University ) and Hal Schenck (currently at Auburn University ) began the journal with the goal of creating a top-tier journal in commutative algebra.
The journal is abstracted and indexed in Current Contents /Physical, Chemical & Earth Sciences, [ 2 ] Science Citation Index Expanded , Scopus , MathSciNet , and zbMATH . [ 3 ] | https://en.wikipedia.org/wiki/Journal_of_Commutative_Algebra |
The Journal of Composite Materials is a peer-reviewed scientific journal that covers the field of materials science . Its editor-in-chief is H.Thomas Hahn ( UCLA ). It was established in 1967 and is published by SAGE Publications in association with the American Society for Composites .
The journal is abstracted and indexed in Scopus and the Science Citation Index Expanded . According to the Journal Citation Reports , its 2020 impact factor is 2.591, ranking it 18th out of 28 journals in the category "Materials Science, Composites". [ 1 ]
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The Journal of Computational Chemistry is a peer-reviewed scientific journal published since 1980 by John Wiley & Sons . It covers research, contemporary developments in theory and methodology, and applications in all areas of computational chemistry , including ab initio quantum chemistry methods and semiempirical methods , density functional theory , molecular mechanics , molecular dynamics , statistical mechanics , cheminformatics , biomolecular structure prediction , molecular design, and bioinformatics .
According to the Journal Citation Reports , the journal has a 2020 impact factor of 3.376, ranking it 80th out of 179 journals in the category "Chemistry, Multidisciplinary". [ 1 ]
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The Journal of Computational and Applied Mathematics is a peer-reviewed scientific journal covering computational and applied mathematics . It was established in 1975 and is published biweekly by Elsevier . The editors-in-chief are Yalchin Efendiev ( Texas A&M University ), Taketomo Mitsui ( Nagoya University ), Michael Kwok-Po Ng ( Hong Kong Baptist University ) and Fatih Tank ( Ankara University ). According to the Journal Citation Reports , the journal has a 2021 impact factor of 2.872. [ 1 ]
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The Journal of Cosmology is a website that describes itself as a "scientific journal". [ 1 ] [ 2 ] It has been criticized for lacking oversight and proper peer-review , and promoting fringe theories. [ 3 ] [ 4 ] [ 5 ] [ 6 ] It was established in 2009 by neuroscientist Rhawn Joseph; as of 2023, Rudolph Schild is the editor-in-chief . [ 7 ]
The Journal of Cosmology is an online publication that contains material on a wide range of subjects in cosmology , astronomy , astrobiology , and Earth and planetary sciences . Writing on biology , geology , physics , chemistry , extinction , the origin and evolution of life, panspermia and Martian colonization and exploration has all been published. [ 7 ] [ 8 ]
The quality of the claimed peer review has been heavily criticized. [ 3 ] [ 9 ] [ 6 ] [ 4 ] [ 5 ] The website promotes fringe viewpoints and speculative viewpoints on astrobiology , astrophysics , and quantum physics . Skeptical blogger and biologist PZ Myers said that "it isn't a real science journal at all, but [the] website of a small group... obsessed with the idea of Hoyle and Wickramasinghe that life originated in outer space and simply rained down on Earth ." [ 6 ] [ 10 ] It was identified as a predatory journal by Jeffrey Beall . [ 3 ]
Scientists who have posted accounts of personal attacks by the journal's staff members include Susan Blackmore , [ 11 ] David Brin , [ 12 ] and PZ Myers. [ 13 ]
In early March 2011, a controversy erupted [ 6 ] [ 14 ] over the publication of a paper by Richard B. Hoover , [ 15 ] a retired NASA scientist, with claims of evidence in meteorites that life on Earth could have come from space via debris carrying life from a comet. The website published a dismissal of the criticism as "a barrage of slanderous attacks" from "crackpots and charlatans", calling themesleves courageous for resisting the "terrorists" whose actions they equated with the Inquisition . [ 16 ]
NASA distanced itself from Hoover's findings, [ 17 ] and issued a statement saying that the paper had been previously submitted in 2007 to International Journal of Astrobiology which did not accept it for review. [ 18 ]
On 11 March, in an open letter to the editors of Science and Nature , Schild proposed to establish a commission to investigate the validity of the Hoover paper, which would be led by three experts appointed by Journal of Cosmology , Science and Nature . [ 19 ] Schild said he would interpret "any refusal to cooperate, no matter what the excuse" from Nature or Science as "vindication for the Journal of Cosmology and the Hoover paper, and an acknowledgment that the editorial policies of the Journal of Cosmology are beyond reproach". [ 19 ] Schild subsequently issued another statement standing by their publication process and suggesting that criticisms were "slander and histrionic tirades", and comparing their critics to "lunatics... unleashed to throw filth", suggesting that their own actions were part of a 2000-year struggle of science against religion. Since their critics had "refused to cooperate" in a review, they reaffirmed the study to be "beyond reproach". [ 20 ]
The James Randi Educational Foundation awarded Hoover the tongue-in-cheek Pigasus Award , for repeatedly announcing, "[a]long with the crackpot Journal of Cosmology ", [ 21 ] widely dismissed claims that he had found signs of life in Mars rocks. [ 21 ] [ 22 ]
On 17 January 2014, NASA reported that a martian rock , named " Pinnacle Island ", that was not in an Opportunity rover image taken on Sol 3528, "mysteriously" appeared 13 days later in a similar image taken on Sol 3540. One possible explanation, presented by Steven Squyres , principal investigator of the Mars Exploration Rover Mission , was that the rover, in one of its turning motions, flicked the rock from a few feet away and into the new location. [ 23 ] [ 24 ] In response to the finding, Rhawn Joseph published an article on the website on 17 January 2014, concluding that the object is in fact a living organism resembling apothecia . [ 25 ] Joseph then filed a writ of mandamus on 27 January 2014 in San Francisco Federal Court , demanding that NASA examine the rock more closely. [ 26 ] [ 27 ] [ 28 ]
NASA had already examined the rock on 8 January 2014 [ 29 ] and confirmed it was a rock with a high sulphur, manganese, and magnesium content. [ 30 ] According to Squyres , "We have looked at it with our microscope. It is clearly a rock." [ 28 ] On 14 February 2014, NASA released an image showing the location from where the " Pinnacle Island " rock was dislodged by the Opportunity rover . | https://en.wikipedia.org/wiki/Journal_of_Cosmology |
The Journal of Crystal Growth is a semi-monthly peer-reviewed scientific journal covering experimental and theoretical studies of crystal growth and its applications. It is published by Elsevier and the editor-in-chief is J. Derby ( University of Minnesota ). [ 1 ]
The Journal of Crystal Growth was founded following the 1966 International Conference on Crystal Growth (ICCG) held in Boston , Massachusetts, United States. Ichiro Sunagawa, who participated in ICCG, wrote in the Journal of the Japanese Association of Crystal Growth that before then, "The crystal growth community was totally fragmented and had remained as a peripheral field at the mercy of other organizations." [ 2 ] [ 3 ] Michael Schieber ( Hebrew University ) later recounted feeling the need for an individual journal on the subject after the conference proceedings were published as a supplement to the Journal of Physics and Chemistry of Solids that had to be additionally ordered by journal subscribers. [ 2 ] [ 4 ] Feeling as though the crystal growth community should not remain at the "discretion of other disciplines for which crystal growth has a secondary importance", he spoke about the idea with a colleague, Kenneth Button , who informed an editor at the North-Holland Publishing Company (now Elsevier). [ 2 ]
The journal launched in 1967, with an editorial board consisting of Schieber as editor-in-chief and co-editors Charles Frank and Nicolás Cabrera . [ 4 ] [ 5 ] At the time the journal employed two U.S. editors, eighteen associate editors from around the world, and an editorial advisory board of sixteen members. [ 4 ]
As of 2015, the journal has continued to serve as the "major venue for papers on crystal growth theory, practice and characterization" and proceedings of various conferences in the field. [ 5 ] According to Tony Stankus, the journal has historically emphasised research contribution on crystals grown from wet solutions and later strongly emphasised research on crystals grown from molten materials or those produced through other processes relevant to the semiconductor industry. [ 6 ]
The American Chemical Society and the Scholarly Publishing and Academic Resources Coalition partnered to develop Crystal Growth and Design as a lower-cost alternative to the Journal of Crystal Growth ; [ 7 ] its first issue was published in 2001. [ 8 ]
In 2017, Elsevier was reported to be retracting four articles from the journal after an author had falsified reviews. The journal was one of several publications affected by the falsifications. [ 9 ] [ 10 ] [ 11 ] [ 12 ]
The journal is abstracted and indexed in the following databases: [ 13 ]
According to Journal Citation Reports , the journal had a 2021 impact factor of 1.830. [ 14 ] | https://en.wikipedia.org/wiki/Journal_of_Crystal_Growth |
The J ournal of Dental Biomechanics is a peer-reviewed academic journal that covers in the field of materials science applied to dentistry . The editors-in-chief are Christoph Bourauel ( University of Bonn ) and Theodore Eliades ( University of Zurich ). It was established in 2009 and published by SAGE Publications . The journal has stopped publications since 2015.
The Journal of Dental Biomechanics is abstracted and indexed in: | https://en.wikipedia.org/wiki/Journal_of_Dental_Biomechanics |
The Journal of Dynamic Behavior of Materials is a quarterly peer-reviewed scientific journal published by Springer Science+Business Media on behalf of the Society for Experimental Mechanics . [ 1 ] Jennifer L. Jordan ( Los Alamos National Laboratory ) has been the editor-in-chief since 2020. [ 2 ] The journal was established in 2015 with Eric N. Brown as the inaugural editor-in-chief. [ 3 ]
The journal is abstracted and indexed in: | https://en.wikipedia.org/wiki/Journal_of_Dynamic_Behavior_of_Materials |
[ 1 ] The Journal of Education for Sustainable Development [ 2 ] is a forum for discussion and dialogues in the emerging field of Education for Sustainable Development (ESD).
The journal is published by Sage Publications India Pvt Ltd , India in association with the Centre for Environment Education .
The journal is a member of the Committee on Publication Ethics (COPE)..It is edited by Prithi Nambiar. [ 3 ]
Journal of Education for Sustainable Development is abstracted and indexed in: | https://en.wikipedia.org/wiki/Journal_of_Education_for_Sustainable_Development |
The Journal of Elastomers and Plastics is a bimonthly peer-reviewed scientific journal that covers materials science of elastomers and plastics . The editor-in-chief is Heshmat A. Aglan ( Tuskegee University ). It was established in 1969 as the Journal of Elastoplastics , obtaining its current name in 1974. The journal is published by SAGE Publications .
The journal is abstracted and indexed in Scopus and the Science Citation Index Expanded . According to the Journal Citation Reports , its 2020 impact factor is 1.833, ranking it 257th out of 334 journals in the category "Materials Science, Multidisciplinary" [ 1 ] and 68th out of 91 journals in the category "Polymer Science". [ 2 ] | https://en.wikipedia.org/wiki/Journal_of_Elastomers_and_Plastics |
The Journal of Electroanalytical Chemistry is a peer-reviewed scientific journal on electroanalytical chemistry , published by Elsevier twice per month. It was originally established in 1959 under the current name, but was known as the Journal of Electroanalytical Chemistry and Interfacial Electrochemistry from 1967 to 1991. It is currently edited by X.-H. Xia ( Nanjing University ). The journal is associated with the International Society of Electrochemistry . While the journal is now published exclusively in English, earlier volumes sometimes published articles in French and German .
The journal, which The New York Times described as "a specialty publication not widely circulated" in 1990, [ 1 ] became more broadly known in 1989 when Martin Fleischmann and Stanley Pons published a description of their controversial cold fusion research in it, [ 2 ] withdrawing their work from publication in Nature after questions were raised during peer review there. [ 1 ]
According to the Journal Citation Reports , Journal of Electroanalytical Chemistry has a 2021 impact factor of 4.598. [ 3 ] It is abstracted and indexed in the following bibliographic databases
This article about an electrochemistry journal is a stub . You can help Wikipedia by expanding it .
See tips for writing articles about academic journals . Further suggestions might be found on the article's talk page . | https://en.wikipedia.org/wiki/Journal_of_Electroanalytical_Chemistry |
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