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Patina ( / p ə ˈ t iː n ə / pə- TEE -nə or / ˈ p æ t ɪ n ə / PAT -ih-nə ) is a thin layer that variously forms on the surface of copper , brass , bronze , and similar metals and metal alloys ( tarnish produced by oxidation or other chemical processes), or certain stones [ 1 ] and wooden furniture (sheen produced by age... | https://en.wikipedia.org/wiki/Patina |
Patinho Feio (Portuguese for "Ugly Duckling", in reference to the fairy tale ) was the first minicomputer designed and manufactured entirely in Brazil. [ 1 ] It was made between 1971 and 1972 in the Polytechnic School of the University of São Paulo by the Digital Systems Laboratory (currently called Department of Compu... | https://en.wikipedia.org/wiki/Patinho_Feio |
The patio process is a process for extracting silver from ore . Smelting , or refining , is most often necessary because silver is only infrequently found as a native element like some metals nobler than the redox couple 2 H + + 2 e − ⇌ H 2 ( gold , mercury , ...). Instead, it is made up of a larger ore body. Thus, sme... | https://en.wikipedia.org/wiki/Patio_process |
Patoka Oil Terminal is a pipeline hub located near the towns of Patoka and Vernon . It services five major pipelines in the second district of the Petroleum Administration for Defense Districts including Dakota Access and the Keystone Pipeline .
The Patoka Oil Terminal Hub is located near the towns of Patoka and Verno... | https://en.wikipedia.org/wiki/Patoka_Oil_Terminal |
E. O. Paton Electric Welding Institute ( Ukrainian : Інститут електрозварювання ім. Є. О. Патона , romanized : Insytut elektrozvariuvannia im. Ye. O. Patona ) is a welding research institution situated in Kyiv , Ukraine . It is named after its founder, Professor Evgeny Paton .
The institute was established in 1934 fo... | https://en.wikipedia.org/wiki/Paton_Institute_of_Electric_Welding |
The patriarch hypothesis is a hypothesis that explains the occurrence of menopause in human females and how a long post-fertile period (up to one third of a female's life-span) [ 1 ] could confer an evolutionary advantage. It is an alternative theory to the grandmother hypothesis which tends to ignore male benefits of ... | https://en.wikipedia.org/wiki/Patriarch_hypothesis |
Patricia Molina is the Richard Ashman, PhD Professor and Department Head of Physiology and Director of the Alcohol and Drug Abuse Center of Excellence (ADACE) at Louisiana State University Health Sciences Center New Orleans . [ 1 ] In 2015, she was the 88th President of the American Physiological Society , and is the ... | https://en.wikipedia.org/wiki/Patricia_E._Molina |
Patricia Ana Matrai is a marine scientist known for her work on the cycling of sulfur. She is a senior research scientist at Bigelow Laboratory for Ocean Sciences .
Matrai is originally from Chile. [ 1 ] Matria has a B.A. from the Universidad de Concepción (1981), an M.S. (1984) and a Ph.D. (1988) from Scripps Institu... | https://en.wikipedia.org/wiki/Patricia_Matrai |
Patricia C. Zambryski is a plant and microbial scientist known for her work on Type IV secretion and cell-to-cell transport in plants. She is also professor emeritus at the University of California, Berkeley . [ 1 ]
She was an elected member of the National Academy of Sciences , the American Association for the Advanc... | https://en.wikipedia.org/wiki/Patricia_Zambryski |
Patrick H. [ 1 ] Scully was a Catholic priest and astronomer who served as a missionary in Cape Town and built the first Catholic parish church in South Africa .
After the Anglo-Dutch Treaty of 1814 , the Colonial Office gave permission for a Catholic priest to be stationed in Cape Town. [ 2 ] Irish priest Patrick H. ... | https://en.wikipedia.org/wiki/Patrick_H._Scully |
Patrick Michael Grundy (16 November 1917, Yarmouth, Isle of Wight – 4 November 1959) was an English mathematician and statistician . He was one of the eponymous co-discoverers of the Sprague–Grundy function and its application to the analysis of a wide class of combinatorial games . [ 1 ]
Grundy received his secondar... | https://en.wikipedia.org/wiki/Patrick_Michael_Grundy |
Patritumab deruxtecan ( U3-1402/ MK-1022 ) is an experimental antibody–drug conjugate developed by Merck and Daiichi Sankyo to treat non-small-cell lung cancer . [ 1 ] [ 2 ] [ 3 ] | https://en.wikipedia.org/wiki/Patritumab_deruxtecan |
Patrizia M. Gianni (born 1952) [ 1 ] is an Italian mathematician specializing in computer algebra . She is known for her early research on Gröbner bases including her discovery of the FGLM algorithm for changing monomial orderings in Gröbner bases, [ 2 ] and for her development of the components of the Axiom computer a... | https://en.wikipedia.org/wiki/Patrizia_Gianni |
A patrocladogram is a cladistic branching pattern that has been precisely modified by use of patristic distances (i.e., divergences between lineages); a type of phylogram . [ 1 ] The patristic distance is defined as, "the number of apomorphic step changes separating two taxa on a cladogram," [ 2 ] and is used exclusive... | https://en.wikipedia.org/wiki/Patrocladogram |
Patronage in astronomy is an approach which one can use to examine the history of astronomy from a cultural standpoint. Rather than simply focusing on the findings and discoveries of individual astronomers, this approach emphasizes the importance of patronage in shaping the field of astronomy. [ 1 ]
An often overlooke... | https://en.wikipedia.org/wiki/Patronage_in_astronomy |
A pattern is a regularity in the world, in human-made design, [ 1 ] or in abstract ideas. As such, the elements of a pattern repeat in a predictable manner. A geometric pattern is a kind of pattern formed of geometric shapes and typically repeated like a wallpaper design.
Any of the senses may directly observe pattern... | https://en.wikipedia.org/wiki/Pattern |
Pattern-Oriented Software Architecture is a series of software engineering books describing software design patterns .
David E. DeLano of C++ Report praised the first volume, writing, "Overall this text is good and I recommend it as an addition to any collection of books on patterns." He said "some of the language and... | https://en.wikipedia.org/wiki/Pattern-Oriented_Software_Architecture |
Collective intelligence Collective action Self-organized criticality Herd mentality Phase transition Agent-based modelling Synchronization Ant colony optimization Particle swarm optimization Swarm behaviour
Social network analysis Small-world networks Centrality Motifs Graph theory Scaling Robustness Systems biology D... | https://en.wikipedia.org/wiki/Pattern_formation |
Pattern gardening is a method of designing gardens influenced by the concepts of design pattern and pattern language originated by Christopher Alexander . It reflects the archetypal patterns of garden making, based on proportions and how the senses react. Patterns give coherence to garden design and communicate creativ... | https://en.wikipedia.org/wiki/Pattern_gardening |
A pattern language is an organized and coherent set of patterns , each of which describes a problem and the core of a solution that can be used in many ways within a specific field of expertise. The term was coined by architect Christopher Alexander and popularized by his 1977 book A Pattern Language .
A pattern langu... | https://en.wikipedia.org/wiki/Pattern_language |
Patterned vegetation is a vegetation community that exhibits distinctive and repetitive patterns. Examples of patterned vegetation include fir waves , tiger bush , and string bog . The patterns typically arise from an interplay of phenomena that differentially encourage plant growth or mortality. A coherent pattern ari... | https://en.wikipedia.org/wiki/Patterned_vegetation |
A patternmaker is a skilled worker who produces patterns on paper or fabric for use in the clothing industry.
Apparel patternmakers draft patterns based on a designer's sketch of a style. The designer gives the sketch to the patternmaker, who can ask questions to determine details the designer is looking for. [ 1 ]
P... | https://en.wikipedia.org/wiki/Patternmaker_(clothing) |
Ants are simple animals and their behavioural repertory is limited to somewhere between ten and forty elementary behaviours. This is an attempt to explain the different patterns of self-organization in ants . [ 1 ]
Ant colonies are self-organized systems: complex collective behaviors arise as the product of interactio... | https://en.wikipedia.org/wiki/Patterns_of_self-organization_in_ants |
The Patterson function is used to solve the phase problem in X-ray crystallography . It was introduced in 1935 by Arthur Lindo Patterson while he was a visiting researcher in the laboratory of Bertram Eugene Warren at MIT . [ 1 ] [ 2 ]
The Patterson function is defined as
P ( u , v , w ) = ∑ h , k , ℓ ∈ Z | F h , k ,... | https://en.wikipedia.org/wiki/Patterson_function |
The Patterson power cell is a cold fusion device invented by chemist James A. Patterson, [ 1 ] which he claimed created 200 times more energy than it used. [ 2 ] Patterson claimed the device neutralized radioactivity without emitting any harmful radiation. [ 1 ] Cold fusion was the subject of an intense scientific cont... | https://en.wikipedia.org/wiki/Patterson_power_cell |
Pattinson's process or pattinsonisation is a method for removing silver from lead , discovered by Hugh Lee Pattinson in 1829 [ 1 ] and patented in 1833.
The process is dependent on the fact that lead which has least silver in it solidifies first on liquefaction , leaving the remaining liquid richer in silver.
In prac... | https://en.wikipedia.org/wiki/Pattinson's_process |
In biochemistry , paucimannosylation is an enzymatic post-translational modification involving the attachment of relatively simple mannose (Man) and N-Acetylglucosamine (GlcNAc) containing carbohydrates ( glycans ) to proteins . [ 1 ] The paucimannosidic glycans may also be modified with other types of monosaccharides ... | https://en.wikipedia.org/wiki/Paucimannosylation |
Paul-Peter Tak is a Dutch immunologist and academic specialising in the fields of internal medicine , rheumatology and immunology . Tak has been the President & CEO of Candel Therapeutics since September 2020.
Tak graduated with a medical degree cum laude from the Amsterdam University Medical Centers and began his med... | https://en.wikipedia.org/wiki/Paul-Peter_Tak |
Armand Paul Alivisatos (born November 12, 1959) is a Greek and American chemist and academic administrator who is the 14th president of the University of Chicago since September 2021. He is a pioneer in nanomaterials development [ 1 ] [ 2 ] and an authority on the fabrication of nanocrystals and their use in biomedical... | https://en.wikipedia.org/wiki/Paul_Alivisatos |
Paul Gardner Allen (January 21, 1953 – October 15, 2018) was an American businessman, computer programmer, researcher, film producer, explorer, sports executive, investor, author, and philanthropist. He co-founded Microsoft Corporation with his childhood friend Bill Gates in 1975, which was followed by the microcompute... | https://en.wikipedia.org/wiki/Paul_Allen |
John Paul Attfield (born 1962) [ 3 ] is a British chemist who is Professor of Materials science in the School of Chemistry at the University of Edinburgh and Director of the Centre for Science at Extreme Conditions (CSEC). [ 4 ] [ 5 ] [ 6 ]
Attfield was educated at Durham Johnston School [ 3 ] in Durham, England and t... | https://en.wikipedia.org/wiki/Paul_Attfield |
Paul Benjamin Ferrara (November 2, 1942 – May 30, 2011) was a scientist and administrator who pioneered the use of DNA profiling in America.
Ferrara graduated from Syracuse University and State University of New York College of Environmental Science and Forestry with doctorate degree in organic chemistry. [ 1 ]
In 19... | https://en.wikipedia.org/wiki/Paul_B._Ferrara |
Paul Anthony Benioff [ 1 ] (May 1, 1930 – March 29, 2022) was an American physicist who helped pioneer the field of quantum computing . Benioff was best known for his research in quantum information theory during the 1970s and 80s that demonstrated the theoretical possibility of quantum computers by describing the firs... | https://en.wikipedia.org/wiki/Paul_Benioff |
Paul Berg (June 30, 1926 – February 15, 2023) was an American biochemist and professor at Stanford University .
He was the recipient of the Nobel Prize in Chemistry in 1980, along with Walter Gilbert and Frederick Sanger . The award recognized their contributions to basic research involving nucleic acids , especially... | https://en.wikipedia.org/wiki/Paul_Berg |
Paul Isaac Bernays ( / b ɜːr ˈ n eɪ z / bur- NAYZ ; Swiss Standard German: [bɛrˈnaɪs] ; 17 October 1888 – 18 September 1977) was a Swiss mathematician who made significant contributions to mathematical logic , axiomatic set theory , and the philosophy of mathematics . He was an assistant and close collaborator of David... | https://en.wikipedia.org/wiki/Paul_Bernays |
The Paul Bunge Prize is an international award for seminal and lasting contributions to the history of scientific instruments. Endowed in 1993 by the late Hans R. Jenemann (1920–1996), [ 1 ] glass chemist at Schott AG in Mainz, and collector and historian of antique chemical balances. The name of the prize commemorates... | https://en.wikipedia.org/wiki/Paul_Bunge_Prize |
Paul Chaleff (born 1947) [ 1 ] is an American ceramist and professor emeritus of Fine Arts at Hofstra University . [ 2 ] He is considered a pioneer of the revival of wood-fired ceramics in the US and credited as one of the first to use wood-burning dragon kilns in the style of the anagama tradition. He is best known as... | https://en.wikipedia.org/wiki/Paul_Chaleff |
Paul Moritz Cohn FRS [ 1 ] (8 January 1924 – 20 April 2006) was Astor Professor of Mathematics at University College London , 1986–1989, and author of many textbooks on algebra . [ 4 ] His work was mostly in the area of algebra , especially non-commutative rings . [ 3 ] [ 5 ]
Cohn was the only child of Jewish parents,... | https://en.wikipedia.org/wiki/Paul_Cohn |
Paul S. Cremer (born 1967) is an American chemist in physical and analytical chemistry at biological interfaces.
Cremer graduated from University of Wisconsin-Madison with a BA in 1990, completed his PhD at University of California, Berkeley in 1996, and completed postdoctoral work at Stanford University (1996-1998). ... | https://en.wikipedia.org/wiki/Paul_Cremer |
Paul E. Ceruzzi (born 1949) is curator emeritus at the Smithsonian's National Air and Space Museum in Washington, D.C. [ 2 ]
Ceruzzi received a BA from Yale University in 1970 and received a Ph.D. from the University of Kansas in 1981, both in American studies . [ 1 ] Before joining the National Air and Space Museum, ... | https://en.wikipedia.org/wiki/Paul_E._Ceruzzi |
Paul Ernest is a contributor to the social constructivist philosophy of mathematics.
Paul Ernest is currently emeritus professor of the philosophy of mathematics education at University of Exeter , UK. [ 1 ] He is best known for his work on philosophical aspects of mathematics education , which includes establishing t... | https://en.wikipedia.org/wiki/Paul_Ernest |
Paul Francis McMillan (3 June 1956 – 2 February 2022) was a British chemist who held the Sir William Ramsay Chair of Chemistry at University College London . [ 1 ] His research considered the study of matter under extreme conditions of temperature and pressure, with a focus on phase transitions, amorphisation, and the ... | https://en.wikipedia.org/wiki/Paul_F._McMillan |
Paul G. Mezey is a Hungarian-Canadian mathematical chemist . He was the Canada Research Chair in Scientific Modeling and Simulation in the Department of Chemistry at the Memorial University of Newfoundland . [ 1 ] He retired from Memorial University in 2018.
Mezey earned a Master's degrees in chemistry, a Ph.D. in Che... | https://en.wikipedia.org/wiki/Paul_G._Mezey |
Paul Albert Gordan (27 April 1837 – 21 December 1912) was a German mathematician known for work in invariant theory and for the Clebsch–Gordan coefficients and Gordan's lemma . [ 1 ] He was called "the king of invariant theory". [ 2 ] [ 3 ] His most famous result is that the ring of invariants of binary forms of fixed ... | https://en.wikipedia.org/wiki/Paul_Gordan |
Paul Hyman Silverman (October 8, 1924 – July 15, 2004) was an American medical researcher in the fields of immunology , epidemiology , and parasitology . [ 1 ] He was recognized for his research on stem cells and on the human genome . [ 2 ]
Silverman was born on October 8, 1924, in Minneapolis , Minnesota . [ 1 ] Grow... | https://en.wikipedia.org/wiki/Paul_H._Silverman |
Paul Hagenmuller (August 3, 1921 – January 7, 2017) was a French chemist. Hagenmuller founded the Laboratoire de Chimie du Solide (Solid-State Chemistry Laboratory) of the French National Centre for Scientific Research (CNRS) and he served as its Director until 1985. He is considered "one of the founders of solid-state... | https://en.wikipedia.org/wiki/Paul_Hagenmuller |
Paul Richard Halmos ( Hungarian : Halmos Pál ; 3 March 3 1916 – 2 October 2006) was a Hungarian -born American mathematician and probabilist who made fundamental advances in the areas of mathematical logic , probability theory , operator theory , ergodic theory , and functional analysis (in particular, Hilbert spaces )... | https://en.wikipedia.org/wiki/Paul_Halmos |
Paul Lyon Houston (born January 27, 1947) is Professor Emeritus of Chemistry at Cornell University and Professor Emeritus of Chemistry and Biochemistry at the Georgia Institute of Technology .
Houston started his professorial career at Cornell University in 1975 following undergraduate study at Yale University , docto... | https://en.wikipedia.org/wiki/Paul_Houston_(chemist) |
Paul J. Gemperline (born 1955) is an American analytical chemist and chemometrician . He is a Distinguished Professor of Chemistry at East Carolina University (ECU) located in Greenville, North Carolina and has been the recipient of several scientific awards, including the 2003 Eastern Analytical Symposium Award in Che... | https://en.wikipedia.org/wiki/Paul_J._Gemperline |
Paul Karrer (21 April 1889 – 18 June 1971) was a Swiss organic chemist best known for his research on vitamins . He and British chemist Norman Haworth won the Nobel Prize for Chemistry in 1937.
Karrer was born in Moscow , Russia to Paul Karrer and Julie Lerch, both Swiss nationals. In 1892 Karrer's family returned to ... | https://en.wikipedia.org/wiki/Paul_Karrer |
Paul Kazuo Kuroda (1 April 1917 – 16 April 2001) was a Japanese-American chemist and nuclear scientist.
He was born on April 1, 1917, in Fukuoka Prefecture, Japan. [ 1 ] He had three children, including Mitzi Kuroda . [ 2 ] He died on April 16, 2001, at his home in Las Vegas, Nevada. [ 3 ]
He received bachelors and d... | https://en.wikipedia.org/wiki/Paul_Kuroda |
Paul Christian Lauterbur (May 6, 1929 – March 27, 2007) was an American chemist who shared the Nobel Prize in Physiology or Medicine in 2003 with Peter Mansfield for his work which made the development of magnetic resonance imaging (MRI) possible. [ 1 ]
Lauterbur was a professor at Stony Brook University from 1963 unt... | https://en.wikipedia.org/wiki/Paul_Lauterbur |
Paul Malliavin ( French: [maljavɛ̃] ; September 10, 1925 – June 3, 2010) was a French mathematician who made important contributions to harmonic analysis and stochastic analysis .
He is known for the Malliavin calculus , an infinite dimensional calculus for functionals on the Wiener space and his probabilistic proof o... | https://en.wikipedia.org/wiki/Paul_Malliavin |
The Paul Pellas-Graham Ryder Award is jointly sponsored by the Meteoritical Society and the Planetary Geology Division of the Geological Society of America . [ 1 ] It recognizes the best planetary science paper, published during the previous year in a peer-reviewed scientific journal, and written by an undergraduate or... | https://en.wikipedia.org/wiki/Paul_Pellas-Graham_Ryder_Award |
Paul Jules Portier ( French pronunciation: [pɔl ʒyl pɔʁtje] ; 22 May 1866 – 26 January 1962) was a French physiologist who made important contributions to the discovery of anaphylaxis and the development of symbiogenesis . [ 1 ] [ 2 ] On a scientific expedition organised by Albert I, Prince of Monaco , he and Charles R... | https://en.wikipedia.org/wiki/Paul_Portier_(physiologist) |
Paul Sabatier ( French: [sabatje] ; 5 November 1854 – 14 August 1941) was a French chemist , born in Carcassonne . In 1912, Sabatier was awarded the Nobel Prize in Chemistry along with Victor Grignard . Sabatier was honoured for his work improving the hydrogenation of organic species in the presence of metals.
Sabat... | https://en.wikipedia.org/wiki/Paul_Sabatier_(chemist) |
Paul A. Strassmann (January 24, 1929 – April 4, 2025) was a Slovak -born American information technology executive, author, and academic. He served as the first Director of Defense Information at the U.S. Department of Defense and as Chief Information Officer (CIO) at NASA. Strassmann was a pioneer in the field of info... | https://en.wikipedia.org/wiki/Paul_Strassman |
Paul Walden ( Latvian : Pauls Valdens ; Russian : Павел Иванович Вальден ; German : Paul von Walden ; 26 July 1863 – 22 January 1957) was a Russian , Latvian and German chemist known for his work in stereochemistry and history of chemistry. In particular, he discovered the Walden rule , [ 1 ] he invented the stereochem... | https://en.wikipedia.org/wiki/Paul_Walden |
Paula L. Diaconescu is a Romanian-American chemistry professor at the University of California, Los Angeles . She is known for her research on the synthesis of redox active transition metal complexes, the synthesis of lanthanide complexes, metal-induced small molecule activation, and polymerization reactions. She is a ... | https://en.wikipedia.org/wiki/Paula_Diaconescu |
The Pauli effect or Pauli's device corollary is the supposed tendency of technical equipment to encounter critical failure in the presence of certain people — originally, Austrian physicist Wolfgang Pauli . The Pauli effect is not related to the Pauli exclusion principle , which is a bona fide physical phenomenon named... | https://en.wikipedia.org/wiki/Pauli_effect |
In quantum mechanics , the Pauli equation or Schrödinger–Pauli equation is the formulation of the Schrödinger equation for spin-1/2 particles, which takes into account the interaction of the particle's spin with an external electromagnetic field . It is the non- relativistic limit of the Dirac equation and can be used ... | https://en.wikipedia.org/wiki/Pauli_equation |
In quantum mechanics , the Pauli exclusion principle (German: Pauli-Ausschlussprinzip ) states that two or more identical particles with half-integer spins (i.e. fermions ) cannot simultaneously occupy the same quantum state within a system that obeys the laws of quantum mechanics . This principle was formulated by Aus... | https://en.wikipedia.org/wiki/Pauli_exclusion_principle |
In mathematical physics and mathematics , the Pauli matrices are a set of three 2 × 2 complex matrices that are traceless , Hermitian , involutory and unitary . Usually indicated by the Greek letter sigma ( σ ), they are occasionally denoted by tau ( τ ) when used in connection with isospin symmetries. σ 1 = σ x = ( 0 ... | https://en.wikipedia.org/wiki/Pauli_matrices |
Pauline Rudd FRSM is a British biochemist and Professor at the Microbiome Institute, University College Cork . [ 2 ] She is a founder of Wessex Biochemicals, a Fellow of the Royal Society of Medicine and was awarded the James Gregory Medal in 2010. [ 3 ]
Rudd grew up in Bournemouth and attended Bournemouth School for ... | https://en.wikipedia.org/wiki/Pauline_Rudd |
Pauling's principle of electroneutrality states that each atom in a stable substance has a charge close to zero. It was formulated by Linus Pauling in 1948 and later revised. [ 1 ] The principle has been used to predict which of a set of molecular resonance structures would be the most significant, to explain the stabi... | https://en.wikipedia.org/wiki/Pauling's_principle_of_electroneutrality |
Pauling's rules are five rules published by Linus Pauling in 1929 for predicting and rationalizing the crystal structures of ionic compounds . [ 1 ] [ 2 ]
For typical ionic solids, the cations are smaller than the anions , and each cation is surrounded by coordinated anions which form a polyhedron . The sum of the ion... | https://en.wikipedia.org/wiki/Pauling's_rules |
Paulo Eduardo Artaxo Netto is a Brazilian atmospheric physicist . [ 1 ]
Born in São Paulo, Brazil, Artaxo pursued his undergraduate and graduate studies at the University of São Paulo, where he obtained both his MSc and PhD in Physics. [ 2 ]
Artaxo has held postdoctoral positions at several institutions, including t... | https://en.wikipedia.org/wiki/Paulo_Artaxo |
The Pauly reaction is a chemical test used for detecting the presence of tyrosine or histidine in proteins. It is named after German chemist Hermann Pauly , who first described the reaction. [ 1 ] When proteins containing either tyrosine or histidine are reacted with diazotized sulfanilic acid under alkaline conditions... | https://en.wikipedia.org/wiki/Pauly_reaction |
PauseAI is a global political movement founded in the Netherlands with the stated aim of achieving global coordination to stop the development of artificial intelligence systems more powerful than GPT-4 , at least until it is known how to build them safely, and keep them under democratic control. [ 1 ] The movement was... | https://en.wikipedia.org/wiki/PauseAI |
Pause Giant AI Experiments: An Open Letter is the title of a letter published by the Future of Life Institute in March 2023. The letter calls "all AI labs to immediately pause for at least 6 months the training of AI systems more powerful than GPT-4 ", citing risks such as AI-generated propaganda, extreme automation of... | https://en.wikipedia.org/wiki/Pause_Giant_AI_Experiments:_An_Open_Letter |
The Pauson–Khand (PK) reaction is a chemical reaction , described as a [2+2+1] cycloaddition . In it, an alkyne , an alkene , and carbon monoxide combine into a α,β- cyclopentenone in the presence of a metal-carbonyl catalyst [ 1 ] [ 2 ] Ihsan Ullah Khand (1935–1980) discovered the reaction around 1970, while working... | https://en.wikipedia.org/wiki/Pauson–Khand_reaction |
The Pauthenier equation states [ 1 ] [ 2 ] that the maximum charge accumulated by a particle modelled by a small sphere passing through an electric field is given by:
Q m a x = 4 π R 2 ϵ 0 p E {\displaystyle Q_{\mathrm {max} }=4\pi R^{2}\epsilon _{0}pE}
where ϵ 0 {\displaystyle \epsilon _{0}} is the permittivity of f... | https://en.wikipedia.org/wiki/Pauthenier_equation |
Pavel Jungwirth (born 20 May 1966 in Prague , Czech Republic ) is a Czech physical chemist. Since 2004, he has been the head of the Senior Research Group at the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences . He has also been a professor in the Faculty of Mathematics and Physics at Ch... | https://en.wikipedia.org/wiki/Pavel_Jungwirth |
Pavement milling ( cold planing , asphalt milling , or profiling ) is the process of removing at least part of the surface of a paved area such as a road , bridge , or parking lot .
Milling removes anywhere from just enough thickness to level and smooth the surface to a full depth removal.
There are a number of differe... | https://en.wikipedia.org/wiki/Pavement_milling |
A paver ( road paver finisher , asphalt finisher , road paving machine ) is a piece of construction equipment used to lay asphalt concrete or Portland cement concrete on roads, bridges, parking lots and other such places. It lays the material flat and provides minor compaction. This is typically followed by final compa... | https://en.wikipedia.org/wiki/Paver_(vehicle) |
A pawtograph is a print of an animal's paw, regarded in some contexts as equivalent to a human signature . This term is used in particular for the practice of collecting pawtographs of celebrity animals. [ 1 ] [ 2 ] The hobby of collecting pawtographs is known as pawtography. [ citation needed ]
A pawtograph is made b... | https://en.wikipedia.org/wiki/Pawtograph |
In computing and telecommunications , the payload is the part of transmitted data that is the actual intended message. Headers and metadata are sent only to enable payload delivery [ 1 ] [ 2 ] and are considered overhead .
In the context of a computer virus or worm , the payload is the portion of the malware which per... | https://en.wikipedia.org/wiki/Payload_(computing) |
In aerospace engineering , payload fraction is a common term used to characterize the efficiency of a particular design. The payload fraction is the quotient of the payload mass and the total vehicle mass at the start of its journey. It is a function of specific impulse , propellant mass fraction and the structural coe... | https://en.wikipedia.org/wiki/Payload_fraction |
Payment and settlement systems are used for financial transactions in India . Covered by the Payment and Settlement Systems Act of 2007 (PSS Act), legislated in December 2007, they are regulated by the Reserve Bank of India (RBI) and the Board for Regulation and Supervision of Payment and Settlement Systems . [ 1 ]
In... | https://en.wikipedia.org/wiki/Payment_and_settlement_systems_in_India |
The Payne rearrangement is the isomerization, under basic conditions , of 2,3-epoxy alcohols to isomeric 1,2-epoxy alcohols with inversion of configuration. Aza- and thia-Payne rearrangements of aziridines and thiiraniums, respectively, are also known. [ 1 ]
Under basic, protic conditions, 2,3-epoxy alcohols undergo a... | https://en.wikipedia.org/wiki/Payne_rearrangement |
Payroll automation [ 1 ] refers to the use of computers to produce paychecks and manage benefit payments for a company or community. Often, payroll automation is integrated into the company's enterprise resource planning system that provides an overall view of the company's or community's finances; in addition to payro... | https://en.wikipedia.org/wiki/Payroll_automation |
Lead(II) acetate is a white crystalline chemical compound with a slightly sweet taste . Its chemical formula is usually expressed as Pb(CH 3 COO) 2 or Pb(OAc) 2 , where Ac represents the acetyl group . Like many other lead compounds, it causes lead poisoning . Lead acetate is soluble in water and glycerin . With water ... | https://en.wikipedia.org/wiki/Pb(C2H3O2)2 |
Tetraethyl lead
Tetraethyllead (commonly styled tetraethyl lead ), abbreviated TEL , is an organolead compound with the formula Pb ( C 2 H 5 ) 4 . It was widely used as a fuel additive for much of the 20th century, first being mixed with gasoline beginning in the 1920s. This "leaded gasoline" had an increased octane r... | https://en.wikipedia.org/wiki/Pb(C2H5)4 |
Lead(II) acetate is a white crystalline chemical compound with a slightly sweet taste . Its chemical formula is usually expressed as Pb(CH 3 COO) 2 or Pb(OAc) 2 , where Ac represents the acetyl group . Like many other lead compounds, it causes lead poisoning . Lead acetate is soluble in water and glycerin . With water ... | https://en.wikipedia.org/wiki/Pb(CH3COO)2 |
Lead(II) carbonate is the chemical compound with the chemical formula PbCO 3 . It is a white, toxic solid. [ 2 ] It occurs naturally as the mineral cerussite . [ 3 ]
Like all metal carbonates, lead(II) carbonate adopts a dense, highly crosslinked structure consisting of intact CO 2− 3 and metal cation sites. As verifi... | https://en.wikipedia.org/wiki/Pb(CO3) |
Lead(II) nitrate is an inorganic compound with the chemical formula Pb ( NO 3 ) 2 . It commonly occurs as a colourless crystal or white powder and, unlike most other lead(II) salts , is soluble in water .
Known since the Middle Ages by the name plumbum dulce , the production of lead(II) nitrate from either metallic le... | https://en.wikipedia.org/wiki/Pb(NO3)2 |
soluble in ammonium acetate (≥ 6 mol/L)
soluble in ammonium tartrate in presence of ammonium chloride and ammonia
Lead(II) sulfate (PbSO 4 ) is a white solid, which appears white in microcrystalline form. It is also known as fast white , milk white , sulfuric acid lead salt or anglesite .
It is often seen in the pla... | https://en.wikipedia.org/wiki/Pb(SO4) |
Plumbylenes (or plumbylidenes ) are divalent organolead(II) analogues of carbenes , with the general chemical formula, R 2 Pb , where R denotes a substituent. Plumbylenes possess 6 electrons in their valence shell , and are considered open shell species.
The first plumbylene reported was the dialkylplumbylene, [(Me 3 ... | https://en.wikipedia.org/wiki/Pb2H4 |
Naples yellow , also called antimony yellow or lead antimonate yellow , is an inorganic pigment that largely replaced lead-tin-yellow and has been used in European paintings since the seventeenth century. [ 2 ] [ 3 ] : 219 While the mineral orpiment is considered to be the oldest yellow pigment, Naples yellow, like Egy... | https://en.wikipedia.org/wiki/Pb2Sb2O7 |
Berryite is a mineral with the formula Pb 3 (Ag,Cu) 5 Bi 7 S 16 . It occurs as gray to blue-gray monoclinic prisms. It is opaque and has a metallic luster . It has a Mohs hardness of 3.5 and a specific gravity of 6.7.
It was first identified in 1965 using X-ray diffraction by mineralogist Leonard Gascoigne Berry (1914... | https://en.wikipedia.org/wiki/Pb3(Ag,Cu)5Bi7S16 |
Lead(II) phosphate is an ionic compound with chemical formula Pb 3 ( P O 4 ) 2 . Lead(II) phosphate is a long-lived electronically neutral reagent chemical. [ 2 ] Despite limited tests on humans, it has been identified as a carcinogen based on tests on animals conducted by the EPA . [ 3 ] Lead(II) phosphate appears as... | https://en.wikipedia.org/wiki/Pb3(PO4)2 |
Lead(II,IV) oxide , also called red lead or minium , is the inorganic compound with the formula Pb 3 O 4 . A bright red or orange solid, it is used as pigment , in the manufacture of batteries , and rustproof primer paints . It is an example of a mixed valence compound , being composed of both Pb(II) and Pb(IV) in the ... | https://en.wikipedia.org/wiki/Pb3O4 |
Lead(II) bromide is the inorganic compound with the formula PbBr 2 . It is a white powder. It is produced in the burning of typical leaded gasolines. [ 4 ]
It is typically prepared from treating solutions of lead salts (e.g., ( lead(II) nitrate ) with bromide salts. This process exploits its low solubility in water ... | https://en.wikipedia.org/wiki/PbBr2 |
Soluble in hot water as well as in presence of alkali hydroxide
Soluble in concentrated HCl (>6M)
Lead(II) chloride (PbCl 2 ) is an inorganic compound which is a white solid under ambient conditions. It is poorly soluble in water. Lead(II) chloride is one of the most important lead -based reagents . It also occurs na... | https://en.wikipedia.org/wiki/PbCl2 |
Lead tetrachloride , also known as lead(IV) chloride , has the molecular formula PbCl 4 . It is a yellow, oily liquid which is stable below 0 °C, and decomposes at 50 °C. [ 2 ] It has a tetrahedral configuration , with lead as the central atom. The Pb– Cl covalent bonds have been measured to be 247 pm and the bond ener... | https://en.wikipedia.org/wiki/PbCl4 |
Lead(II) chromate is an inorganic compound with the chemical formula Pb Cr O 4 . It is a bright yellow salt that is very poorly soluble in water. It occurs also as the mineral crocoite . It is used as a pigment.
Two polymorphs of lead chromate are known, orthorhombic and the more stable monoclinic form. Monoclinic l... | https://en.wikipedia.org/wiki/PbCrO4 |
Lead(II) fluoride is the inorganic compound with the formula Pb F 2 . It is a white solid. The compound is polymorphic , at ambient temperatures it exists in orthorhombic (PbCl 2 type) form, while at high temperatures it is cubic ( Fluorite type ). [ 2 ]
Lead(II) fluoride can be prepared by treating lead(II) hydroxi... | https://en.wikipedia.org/wiki/PbF2 |
Lead tetrafluoride is a compound of lead and fluorine . The yellow solid (melting point 600 °C) is the only room-temperature stable tetrahalide of lead. [ 3 ] Lead tetrafluoride is isostructural with tin(IV) fluoride and contains planar layers of octahedrally coordinated lead, where the octahedra share four corners an... | https://en.wikipedia.org/wiki/PbF4 |
Lead(II) iodide (or lead iodide ) is a chemical compound with the formula PbI 2 . At room temperature , it is a bright yellow odorless crystalline solid, that becomes orange and red when heated. [ 11 ] It was formerly called plumbous iodide .
The compound currently has a few specialized applications, such as the manuf... | https://en.wikipedia.org/wiki/PbI2 |
Lead(IV) oxide , commonly known as lead dioxide , is an inorganic compound with the chemical formula PbO 2 . It is an oxide where lead is in an oxidation state of +4. [ 1 ] It is a dark-brown solid which is insoluble in water. [ 2 ] It exists in two crystalline forms. It has several important applications in electroche... | https://en.wikipedia.org/wiki/PbO2 |
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