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Journal of Photochemistry and Photobiology The is a series of peer-reviewed scientific journals covering the fields of photochemistry and photobiology, published by Elsevier. It was originally established in 1972, and split into "A: Chemistry" and "B: Biology" in 1987. A third title; "C: Photochemistry Reviews", was established in 2000 and is the official journal of the Japanese Photochemistry Association. The "Journal of Photochemistry" was established in 1972 under founding editor-in-chief Richard P. Wayne. Originally published quarterly, by 1987 frequency had increased to monthly. In 1986, the 38th Council of the American Society for Photobiology (ASP) established a committee to investigate the proposal that the European Society for Photobiology (ESP) share the operation of the ASP official journal, "Photochemistry and Photobiology". In 1987, financial and contractual problems prevented agreement and, instead, ESP contracted with Elsevier, leading to the restructuring of the "Journal of Photochemistry" into two separate journals: the "A: Chemistry", continuing under Richard P. Wayne and covering photochemistry and the "B: Biology" under founding editor Giulio Jori, covering photobiology. The "C: Photochemistry Reviews" was first published in 2000 with Akira Fujishima as founding editor-in-chief. When the journal was first established, it aimed to increase from two issues a year to four, an objective achieved and maintained since 2003. The "A: Chemistry" is published biweekly | https://en.wikipedia.org/wiki?curid=30463129 |
Journal of Photochemistry and Photobiology There is no editor-in-chief; editorial responsibility is shared and divided geographically with Hiroshi Masuhara covering Asia, Russ Schmehl covering America, and Monique Martin covering Europe. The "A: Chemistry" is abstracted and indexed in Biosis Previews, Chemical Abstracts, Chemical Citation Index, Current Contents/Physics, Chemistry & Engineering, Engineering Index, Metals Abstracts, PASCAL, Physics Abstracts, Physikalische Berichte, Polymer Contents, Science Citation Index and Scopus. According to the "Journal Citation Reports", the journal has a 2014 impact factor of 2.495. The "B: Biology" is published monthly. The editors are Robert Carpentier and Dominic J. Robinson. Carpentier covers the fields of biophysics, biomolecular spectroscopy, photosynthesis, environmental photobiology, oxygen radicals, DNA repair, and UV-/VIS effects. Robinson covers photomedicine, photodynamic therapy, photosensitisers and dermatology. The "B: Biology" is abstracted and indexed in BIOSIS, Cambridge Scientific Abstracts, Chemical Abstracts, Current Contents, BIOBASE/Current Awareness in Biological Sciences, EMBASE, Embiology, Engineering Index, Metals Abstracts, PASCAL, Physics Abstracts, Physikalische Berichte, Polymer Contents, Science Citation Index, and Scopus. According to the "Journal Citation Reports", the journal has a 2016 impact factor of 2.673. "C: Photochemistry Reviews" focusses on photochemistry literature reviews | https://en.wikipedia.org/wiki?curid=30463129 |
Journal of Photochemistry and Photobiology It is the official journal of the Japanese Photochemistry Association and is published quarterly. The editor-in-chief is Noboru Kitamura. The "C: Photochemistry Reviews" is abstracted and indexed in BIOSIS Previews, Chemistry & Chemical Engineering, Chemistry Citation Index, Current Contents/Physical, Chemical & Earth Sciences, Science Citation Index and Scopus. According to the "Journal Citation Reports", the journal has a 2014 impact factor of 16.094. | https://en.wikipedia.org/wiki?curid=30463129 |
Optical unit The Optical Unit is a dimensionless units of length used in optical microscopy. Because every diffraction limited system have their resolution proportional to wavelength / NA, it is convenient for comparison to use this unit. There are actually 2 units, one "axial" (along the optical axis of the objective) and one "radial". formula_1 formula_2 where : Note : formula_8 = numerical aperture | https://en.wikipedia.org/wiki?curid=30468706 |
Textbook of Biochemistry Textbook of Biochemistry, first published in 1928, is scientific textbook authored by Alexander Thomas Cameron. The textbook became a standard of its field, and, by 1948, had gone through six editions, in addition to one Chinese and two Spanish editions. "Textbook of Biochemistry" consists entirely of lecture manuscripts given by the author, Alexander Thomas Cameron, over several years. Cameron had lectured at the University of Manitoba since 1909, but was never a fluent speaker. To compensate for this, he would write out his lectures in full. Cameron was encouraged by students and friends to submit his lecture manuscripts for publication. The textbook's first edition was published with a preface by Swale Vincent, Professor of Physiology at the University of London. "Textbook of Biochemistry" is divided into the following chapters: Introduction to the concept of biochemistry, and a review of catalytic reactions and pH. Ideas regarding carbohydrates, lipids, and proteins. The importance of bacterial and chemical activity in organisms. The chemistry of tissues, intracellular synthesis, products of metabolism, and vitamins. The agents governing metabolic processes. A review of the present status of immunological biochemistry, and applications of biochemistry in industry. Treat B. Johnson, writing for the "Journal of Chemical Education," acknowledged the difficulty of concisely covering the rapidly growing field of biochemistry, but concluded that Cameron has "done quite well | https://en.wikipedia.org/wiki?curid=30469350 |
Textbook of Biochemistry " He described "Textbook of Biochemistry" as "not a book that follows the ordinary logical procedure usually associated with such texts," and complements Cameron on a "dogmatic treatment which is really stimulating." "The British Medical Journal" also gave a favourable review, writing that "the busy medical student will find this book a concise account of the facts with which he is expected to become familiar." However, it also observed that the book contains several statements that are "definitely not in agreement with the facts as at present known." The reviewer contradicts, for example, the book's assertions that urinal ammonia is formed in the kidneys from urea, and that pepsin does not attack the CO-NH links in proteins. "Textbook of Biochemistry", being the first concise and authoritative work in its field, became a standard text. By 1948, it had gone through six editions, in addition to one Chinese and two Spanish editions. | https://en.wikipedia.org/wiki?curid=30469350 |
C13H20 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=30471780 |
Chlorine azide (ClN) is an inorganic compound that was discovered in 1908 by Friedrich Raschig. Concentrated is notoriously unstable and may spontaneously detonate at any temperature. is prepared by passing chlorine gas over silver azide, or by an addition of acetic acid to a solution of sodium hypochlorite and sodium azide. When treated with ammonia it is conceivable that one or more of the three possible azinamines, NHN, NH(N), and N(N) may be formed. is extremely sensitive. It may explode, sometimes even without apparent provocation; it is thus too sensitive to be used commercially unless first diluted in solution. reacts explosively with 1,3-butadiene, ethane, ethene, methane, propane, phosphorus, silver azide, and sodium. On contact with acid, chlorine azide decomposes, evolving toxic and corrosive hydrogen chloride gas. Its shipment is subject to strict reporting requirements and regulations by the US Department of Transportation. | https://en.wikipedia.org/wiki?curid=30471922 |
Bioelectrochemistry is a branch of electrochemistry and biophysical chemistry concerned with electrophysiological topics like cell electron-proton transport, cell membrane potentials and electrode reactions of redox enzymes. The beginnings of bioelectrochemistry, as well as those of electrochemistry, are closely related to physiology through the works of Luigi Galvani and then Alessandro Volta. The first modern work in this field is considered that of the German physiologist Julius Bernstein (1902) concerning the source of biopotentials due to different ion concentration through the cell's membrane. The domain of bioelectrochemistry has grown considerably over the past century, maintaining the close connections to various medical and biological and engineering disciplines like electrophysiology, biomedical engineering, and enzyme kinetics. The achievements in this field have been awarded several Nobel prizes for Physiology or Medicine. Among prominent electrochemists who have contributed to this field one could mention John Bockris. | https://en.wikipedia.org/wiki?curid=30473418 |
C17H18O5 The molecular formula CHO, molar mass: 302.32 g/mol, exact mass: 302.115423686 u, may refer to: | https://en.wikipedia.org/wiki?curid=30480366 |
Recode (database) RECODE is a database of "programmed" frameshifts, bypassing and codon redefinition used for gene expression. | https://en.wikipedia.org/wiki?curid=30483675 |
Carboximidate Carboximidates (or more general imidates) are organic compounds, which can be thought of as esters formed between a carboximidic acid (R-C(=NR')OH) and an alcohol, with the general formula R-C(=NR')OR". They are also known as imino ethers, since they resemble imines (>C=N-) with an oxygen atom connected to the carbon atom. Imidates may be generated by a number of synthetic routes, but are in general formed by the Pinner reaction. This proceeds via the acid catalyzed attack of nitriles by alcohols. Imidates produced in this manner are formed as their hydrochloride salts, which are sometimes referred to as Pinner salts. Carboximidates are also formed as intermediates in the Mumm rearrangement and the Overman rearrangement. An amidate/imidate anion is formed upon deprotonation of an amide or imidic acid. Since amides and imidic acids are tautomers, they form the same anion upon deprotonation. The two names are thus synonyms describing the same anion, although arguably, imidate refers to the resonance contributor on the left, while amidate refers to the resonance contributor on the right. However, they are distinguished when they act as ligands for transition metals, with "O-"bound species referred to as imidates and "N"-bound species referred to as amidates. They can be considered aza-substituted analogues of enolates with the formula R-N=C(O)R. Carboximidates are good electrophiles and undergo a range of addition reactions; with aliphatic imidates generally reacting faster than aromatic imidates | https://en.wikipedia.org/wiki?curid=30485312 |
Carboximidate They can be hydrolyzed to give esters and by an analogous process react with amines (including ammonia) to form amidines. Aliphatic imidates react with an excess of alcohol under acid catalysis to form orthoesters RC(OR), aromatic imidates can also be converted but far less readily. Named after Arthur William Chapman, who first described it, this is the thermal conversion of aryl N‐arylbenzimidates to the corresponding amides. It is conceptually similar to the Newman–Kwart rearrangement. Carboximidates can act as protecting group for alcohols. For example, the base catalyzed reaction of benzyl alcohol upon trichloroacetonitrile yields a trichloroacetimidate. This species has orthogonal stability to acetate and TBS protections and may be cleaved by acid hydrolysis. | https://en.wikipedia.org/wiki?curid=30485312 |
Synthetic gene database (SGDB) is a database of artificially engineered genes. | https://en.wikipedia.org/wiki?curid=30493924 |
TassDB (TAndem Splice Site DataBase) is a database of tandem splice sites of eight species | https://en.wikipedia.org/wiki?curid=30493979 |
Purine nucleotide cycle The purine nucleotide cycle is a metabolic pathway in which ammonia and fumarate are generated from aspartate and inosine monophosphate (IMP) in order to regulate the levels of adenine nucleotides, as well as to facilitate the liberation of ammonia from amino acids. This pathway was first described by John Lowenstein, who outlined its importance in processes including amino acid catabolism and regulation of flux through glycolysis and the Krebs cycle. The cycle is composed of three enzyme-catalysed reactions. The first stage is the deamination of the purine nucleotide Adenosine monophosphate (AMP) to form inosine monophosphate (IMP), catalysed by the enzyme AMP deaminase: The second stage is the formation of adenylosuccinate from IMP and the amino acid aspartate, which is coupled to the energetically favourable hydrolysis of GTP, and catalysed by the enzyme adenylosuccinate synthetase: Finally, Adenylosuccinate is cleaved by the enzyme adenylosuccinate lyase to release fumarate and regenerate the starting material of AMP: A recent study conducted by Sridharan et al. (AJP Cell Physiology, 2008, 295:C29-C37) showed that activation of HIF-1α allows cardiomyocytes to sustain mitochondrial membrane potential during anoxic stress by utilizing fumarate produced by adenylosuccinate lyase as an alternate terminal electron acceptor in place of oxygen. This mechanism should help provide protection in the ischemic heart. This cycle occurs in Skeletal muscle myocyte's cytosolic compartment | https://en.wikipedia.org/wiki?curid=30494415 |
Purine nucleotide cycle This reaction helps to dispose AMP produced after following reaction. 2 ADP → ATP + AMP (Catalysed by Adenylyl kinase/Myokinase) occurs during strenuous exercise, fasting or starvation when ATP reservoirs run low. 1) Synthesis of fumarate Fumarate is an intermediate of TCA cycle and enters the mitochondria by converting into malate and utilising the malate shuttle where it is converted into Oxaloacetic acid (OAA). OAA either enters into TCA cycle or converts into aspartate in the mitochondria. Aspartate can re-enter purine nucleotide cycle. Oxaloacetic acid + Glutamate ↔ α-Ketoglutarate + Aspartate 2) Synthesis of ammonia (Ammonia genesis) The glutamate produced by OAA as above gains an NH to become a Glutamine and enters the circulation to reach kidneys. In kidneys, glutamine is deaminated twice to form glutamate and then α Ketoglutarate. These NH molecules neutralise the organic acids (lactic acid and ketone bodies) produced in the muscles. | https://en.wikipedia.org/wiki?curid=30494415 |
Univec UniVec is a database that can be used to remove vector contamination from DNA sequences. | https://en.wikipedia.org/wiki?curid=30498055 |
UTRdb is a database of 5' and 3' untranslated sequences of eukaryotic mRNAs | https://en.wikipedia.org/wiki?curid=30498118 |
UTRome is a database of three-prime untranslated regions in C. elegans | https://en.wikipedia.org/wiki?curid=30498206 |
VectorDB was a database of sequence information for common vectors used in molecular biology | https://en.wikipedia.org/wiki?curid=30498283 |
Brosyl In organic chemistry, brosyl (or para"-bromophenylsulfonyl) is a functional group with the chemical formula BrCHSO. This group is usually introduced using the compound brosyl chloride, BrCHSOCl, which forms sulfonyl esters and amides of p"-bromophenylsulfonic acid. The term brosylate refers to the anion of "p"-bromophenylsulfonic acid (BrCHSO). | https://en.wikipedia.org/wiki?curid=30500996 |
Artade ARTADE (ARabidopsis Tiling Array-based Detection of Exons) is a database for the annotation of genome-wide tiling-array data in Arabidopsis | https://en.wikipedia.org/wiki?curid=30509110 |
Annual Review of Chemical and Biomolecular Engineering is an annual peer-reviewed scientific journal published by Annual Reviews, covering chemical and biomolecular engineering. The editor-in-chief is John M. Prausnitz (University of California at Berkeley). According to the "Journal Citation Reports", the journal has a 2014 impact factor of 8.676. | https://en.wikipedia.org/wiki?curid=30528077 |
Annual Review of Condensed Matter Physics The is an annual peer-reviewed review journal published by Annual Reviews. It was established in 2010 and covers advances in condensed matter physics and related subjects. The editor-in-chief is James S. Langer (University of California, Santa Barbara). According to the "Journal Citation Reports", the journal has a 2016 impact factor of 18.588. | https://en.wikipedia.org/wiki?curid=30528084 |
Magnonics is an emerging field of modern magnetism, which can be considered a sub-field of modern solid state physics. combines the study of waves and magnetism. Its main aim is to investigate the behaviour of spin waves in nano-structure elements. In essence, spin waves are a propagating re-ordering of the magnetisation in a material and arise from the precession of magnetic moments. Magnetic moments arise from the orbital and spin moments of the electron, most often it is this spin moment that contributes to the net magnetic moment. Following the success of the modern hard disk, there is much current interest in future magnetic data storage and using spin waves for things such as 'magnonic' logic and data storage. Similarly, spintronics looks to utilize the inherent spin degree of freedom to complement the already successful charge property of the electron used in contemporary electronics. Modern magnetism is concerned with furthering the understanding of the behaviour of the magnetisation on very small (sub-micrometre) length scales and very fast (sub-nanosecond) timescales and how this can be applied to improving existing or generating new technologies and computing concepts. A magnon torque device was invented and later perfected at the National University of Singapore's Electrical & Computer Engineering department, which is based on such potential uses, with results published on November 29, 2019, in Science. A magnonic crystal is a magnetic metamaterial with alternating magnetic properties | https://en.wikipedia.org/wiki?curid=30530797 |
Magnonics Like conventional metamaterials, their properties arise from geometrical structuring, rather than their bandstructure or composition directly. Small spatial inhomogeneities create an effective macroscopic behaviour, leading to properties not readily found in nature. By alternating parameters such as the relative permeability or saturation magnetisation, there exists the possibility to tailor 'magnonic' bandgaps in the material. By tuning the size of this bandgap, only spin wave modes able to cross the bandgap would be able to propagate through the media, leading to selective propagation of certain spin wave frequencies. Spin waves can propagate in magnetic media with magnetic ordering such as ferromagnets and antiferromagnets. The frequencies of the precession of the magnetisation depend on the material and its magnetic parameters, in general precession frequencies are in the microwave from 1–100 GHz, exchange resonances in particular materials can even see frequencies up to several THz. This higher precession frequency opens new possibilities for analogue and digital signal processing. Spin waves themselves have group velocities on the order of a few km per second. The damping of spin waves in a magnetic material also causes the amplitude of the spin wave to decay with distance, meaning the distance freely propagating spin waves can travel is usually only several 10's of μm | https://en.wikipedia.org/wiki?curid=30530797 |
Magnonics The damping of the dynamical magnetisation is accounted for phenomenologically by the Gilbert damping constant in the Landau-Lifshitz-Gilbert equation (LLG equation), the energy loss mechanism itself is not completely understood, but is known to arise microscopically from magnon-magnon scattering, magnon-phonon scattering and losses due to eddy currents. The Landau-Lifshitz-Gilbert equation is the 'equation of motion' for the magnetisation. All of the properties of the magnetic systems such as the applied bias field, the sample's exchange, anisotropy and dipolar fields are described in terms of an 'effective' magnetic field that enters the Landau–Lifshitz–Gilbert equation. The study of damping in magnetic systems is an ongoing modern research topic. The LL equation was introduced in 1935 by Landau and Lifshitz to model the precessional motion of magnetization formula_1 in a solid with an effective magnetic field formula_2 and with damping. Later, Gilbert modified the damping term, which in the limit of small damping yields identical results. The LLG equation is, The constant formula_4 is the Gilbert phenomenological damping parameter and depends on the solid, and formula_5 is the electron gyromagnetic ratio. Here formula_6 Research in magnetism, like the rest of modern science, is conducted with a symbiosis of theoretical and experimental approaches. Both approaches go hand-in-hand, experiments test the predictions of theory and theory provides explanations and predictions of new experiments | https://en.wikipedia.org/wiki?curid=30530797 |
Magnonics The theoretical side focuses on numerical modelling and simulations, so called micromagnetic modelling. Programs such as OOMMF or NMAG are micromagnetic solvers that numerically solve the LLG equation with appropriate boundary conditions. Prior to the start of the simulation, magnetic parameters of the sample and the initial groundstate magnetisation and bias field details are stated. Experimentally, there are many techniques that exist to study magnetic phenomena, each with its own limitations and advantages. The experimental techniques can be distinguished by being time-domain (optical and field pumped TR-MOKE), field-domain (ferromagnetic resonance (FMR)) and frequency-domain techniques (Brillouin light scattering (BLS), vector network analyser - ferromagnetic resonance (VNA-FMR)). Time-domain techniques allow the temporal evolution of the magnetisation to be traced indirectly by recording the polarisation response of the sample. The magnetisation can be inferred by the so-called 'Kerr' rotation. Field-domain techniques such as FMR tickle the magnetisation with a CW microwave field. By measuring the absorption of the microwave radiation through the sample, as an external magnetic field is swept provides information about magnetic resonances in the sample. Importantly, the frequency at which the magnetisation precesses depends on the strength of the applied magnetic field. As the external field strength is increased, so does the precession frequency | https://en.wikipedia.org/wiki?curid=30530797 |
Magnonics Frequency-domain techniques such as VNA-FMR, examine the magnetic response due to excitation by an RF current, the frequency of the current is swept through the GHz range and the amplitude of either the transmitted or reflected current can be measured. Modern ultrafast lasers allow femtosecond (fs) temporal resolution for time-domain techniques, such tools are now standard in laboratory environments. Based on the magneto-optic Kerr effect, TR-MOKE is a pump-probe technique where a pulsed laser source illuminates the sample with two separate laser beams. The 'pump' beam is designed to excite or perturb the sample from equilibrium, it is very intense designed to create highly non-equilibrium conditions within the sample material, exciting the electron, and thereby subsequently the phonon and the spin system. Spin-wave states at high energy are excited and subsequently populate the lower lying states during their relaxation path's. A much weaker beam called a 'probe' beam is spatially overlapped with the pump beam on the magnonic material's surface. The probe beam is passed along a delay line, which is a mechanical way of increasing the probe path length. By increasing the probe path length, it becomes delayed with respect to the pump beam and arrives at a later time on the sample surface. Time-resolution is built in the experiment by changing the delay distance. As the delay line position is stepped, the reflected beam properties are measured | https://en.wikipedia.org/wiki?curid=30530797 |
Magnonics The measured Kerr rotation is proportional to the dynamic magnetisation as the spin-waves propagate in the media. The temporal resolution is limited by the temporal width of the laser pulse only. This allows to connect ultrafast optics with a local spin-wave excitation and contact free detection in magnonic metamaterials, photomagnonics. | https://en.wikipedia.org/wiki?curid=30530797 |
Spokane bombing attempt The occurred on January 17, 2011, when a radio-controlled-shaped pipe bomb was found and defused in Spokane, Washington along the route of that year's Martin Luther King Jr. memorial march. On March 9, 2011, the Federal Bureau of Investigation (FBI) arrested Kevin William Harpham, 36, of Addy, Washington. On December 20, 2011 he was sentenced to 32 years in prison for the attempted bombing. According to the FBI, the bomb was a "viable device" that could have sprayed marchers with shrapnel and caused multiple casualties; it also contained rat poison to prevent bleeding wounds from coagulating. According to the FBI, the bombing may have been racially motivated, and its timing was likely not a coincidence. The "New York Times" said that the bomb had been reported to police at roughly 9:25 a.m. that morning. The bomb was found in a Swiss Army brand backpack that also contained two T-shirts. One of the shirts mentioned a rally against cancer in Stevens County, Washington, while the other mentioned a 2009 play put on by students at Chewelah, Washington high school (also in Stevens County). Police sent bomb-sniffing dogs, a robot, and specially trained officers to the location where the bomb was found. After the bomb was defused, the backpack was sent to the Federal Bureau of Investigation laboratory in Quantico, Virginia for further analysis. According to the Rev. Percy "Happy" Watkins, most people at the march did not know about the bomb threat at the time it happened | https://en.wikipedia.org/wiki?curid=30533901 |
Spokane bombing attempt The FBI offered a $20,000 reward for any information leading to the capture of those responsible. On March 9, 2011, the FBI arrested white supremacist and separatist Kevin William Harpham, 36, of Addy, Washington, in connection with the bombing attempt. On May 3, 2011, Harpham's lawyers requested a four-month delay in his federal trial for attempted use of a weapon of mass destruction, contending that Harpham faced up to life in prison and they would need more time to prepare. Harpham had pleaded not guilty, and remained in jail without bail from the time of his arrest. On May 20, 2011, U.S. District Judge Justin Quackenbush agreed to delay Harpham's trial until August 22, 2011. Documents made public revealed the bomb had a "welded blast plate" and contained shrapnel. The shrapnel was further combined with an anticoagulant rat poison apparently intended to prevent any resulting wounds from clotting, and with human feces, to cause infection. On September 14, 2011, Harpham pleaded guilty to setting the device, but on December 20, 2011, hours before he was due to be sentenced, Harpham tried to withdraw his guilty plea, claiming that the device in his backpack didn't meet the legal definition of a bomb. After rejecting the request and expressing disbelief at Harpham's claim that the device was not intended to hit parade-goers, Quackenbush sentenced him to 32 years in prison, followed by supervised release for life. He will also be required to complete counselling | https://en.wikipedia.org/wiki?curid=30533901 |
Spokane bombing attempt He is serving his sentence at United States Penitentiary, Lompoc in Lompoc, California. | https://en.wikipedia.org/wiki?curid=30533901 |
Ferric reducing ability of plasma (FRAP, also "Ferric ion reducing antioxidant power") is an antioxidant capacity assay that uses Trolox as a standard. The FRAP assay was first performed by Iris Benzie and J. J. Strain of the Human Nutrition Research Group at the University of Ulster, Coleraine. The method is based on the formation of O-Phenanthroline-Fe(2+) complex and its disruption in the presence of chelating agents. This assay is often used to measure the antioxidant capacity of foods, beverages and nutritional supplements containing polyphenols. A reaction mixture containing 1 ml of 0.05% O -Phenanthroline in methanol, 2 ml ferric chloride (200 M) and 2 ml of various concentrations ranging from 10 to 1000 g was incubated at room temperature for 10 min and the absorbance of the same was measured at 510 nm. EDTA was used as a classical metal chelator. The experiment was performed in triplicates. The ferric reducing activity of date seed extract was estimated based on the method of Benzie and Strain (1999). The FRAP reagent was prepared by mixing 50 ml of acetate buffer (0.3 M) at pH 3.6, 5 ml of tripyridyltriazine (TPTZ) solution 10 mM prepared in HCl (40 mM) and 5 ml of ferric chloride solution (FeCl3) (20 mM). 2 ml of the freshly prepared FRAP reagent was added to 10 lL of the extract. Then the absorbance was measured at 593 nm against the blank after 10 min at room temperature. The standard curve was constructed using Trolox. The result was expressed as Trolox equivalent in mg/100 g of dry weight (DW) date seed. | https://en.wikipedia.org/wiki?curid=30534597 |
OMEGA process The ("Only MEG Advantage") is a process by Shell Global Solutions that is used to produce ethylene glycol from ethylene. This process comprises two steps, the controlled oxidation of ethylene to ethylene oxide, and the net hydrolysis of ethylene oxide to monoethylene glycol (MEG). The first chemical plant using the was started in South Korea. Subsequent OMEGA plants have been started in Saudi Arabia and Singapore. Shell claims that this process, compared to conventional ones, does not produce higher glycols, uses less steam and water, and generates less waste. To produce ethylene oxide, ethylene is oxidized with dioxygen in the presence of a silver catalyst. Some ethylene is over-oxidized to carbon dioxide and water, which is wasteful; early processes only gave ~ 65% selectivity for ethylene oxide as a result. In the OMEGA process, over-oxidation is reduced by including ethyl chloride as a moderator. Conventionally, monoethylene glycol (HOCHOH) is produced by the controlled hydrolysis of ethylene oxide (CHO). The monoethylene glycol product is also able to react with ethylene oxide to give diethylene glycol, and so on; sequential reaction with ethylene oxide is how poly(ethylene glycol) is produced. Due to monoethylene glycol's high boiling point, purification by distillation is energy intensive. In the OMEGA process, the ethylene oxide reacts with carbon dioxide (CO) to yield ethylene carbonate (CHO). Ethylene carbonate is subsequently hydrolyzed to monoethylene glycol and carbon dioxide | https://en.wikipedia.org/wiki?curid=30535968 |
OMEGA process The carbon dioxide is released in this step again and can be fed back into the process circuit. This process is 99.5% selective for monoethylene glycol. This part of the was originally developed by Mitsubishi Chemicals, and it has been exclusively licensed to Shell. | https://en.wikipedia.org/wiki?curid=30535968 |
Organosolv In industrial paper-making processes, organosolv is a pulping technique that uses an organic solvent to solubilise lignin and hemicellulose. It has been considered in the context of both pulp and paper manufacture and biorefining for subsequent conversion of cellulose to fuel ethanol. The process was invented by Theodor Kleinert in 1968 as an environmentally benign alternative to kraft pulping. has several advantages when compared to other popular methods such as kraft or sulfite pulping. In particular, the ability to obtain relatively high quality lignin adds value to a process stream otherwise considered as waste. solvents are easily recovered by distillation, leading to less water pollution and elimination of the odour usually associated with kraft pulping. pulping involves contacting a lignocellulosic feedstock such as chipped wood with an aqueous organic solvent at temperatures ranging from 140 to 220 °C. This causes lignin to break down by hydrolytic cleavage of alpha aryl-ether links into fragments that are soluble in the solvent system. Solvents used include acetone, methanol, ethanol, butanol, ethylene glycol, formic acid, and acetic acid. The concentration of solvent in water ranges from 40 to 80%. Higher boiling solvents have the advantage of a lower process pressure. This is weighed against the more difficult solvent recovery by distillation. Ethanol has been suggested as the preferred solvent due to cost and easy recovery | https://en.wikipedia.org/wiki?curid=30537541 |
Organosolv Although butanol is shown to remove more lignin than other solvents and solvent recovery is simplified due to immiscibility in water, its high cost limits its use. Numerous authors report that pulping with ethanol-water solutions gives a lignin free pulp yield 4–4.5% higher than that of kraft pulp. The commonly used solvents acetone and ethanol have been examined with respect to pulp properties. The pulping of wheat straw with 40% mixtures of acetone or ethanol with water requires 60 minutes at 180 °C to give good pulp properties. Organic solvents are almost always used as a mixture with water for process considerations such as reducing the vapour pressure and lowering the pH in order to also solubilised hemicellulose. Only some small organosolv pulp mills are run today for production of pulp from annual renewable non wood fibre sources like straw, bagasse, etc. Recently, due to the popularity of second generation biofuels, the organosolv process has been considered in the context of bioethanol production. Cellulose from the organosolv process is susceptible to enzymatic hydrolysis into glucose followed by fermentation to dilute ethanol. The organosolv fractionation of mountain beetle killed lodgepole pine has yielded 97% conversion to glucose. Pan et al. recovered 79% of the lignin using conditions of 170 °C, 1.1% w/w HSO, 65% v/v ethanol for 60 minutes. Furthermore, ethanol organosolv pretreated rice straw was used to produce biohydrogen using "Enterobacter aerogenes" | https://en.wikipedia.org/wiki?curid=30537541 |
Organosolv The effect of temperature (120–180 °C), residence time (30–90 min), and ethanol concentration (45–75% v/v) on the hydrogen yield, residual biomass, and lignin recovery was investigated using RSM. The glucose concentration at the optimum conditions was 4.22-fold of untreated straw. The recovery of lignin from ethylene glycol organosolv pulping can be effected by 3 times dilution with acidified water. The lignin precipitates and forms spherical aggregates ranging from 0.5–2.5 µm. Filtration, while time consuming, is then most effective while the mixture is hot (>100 °C). Recovery can be achieved by filtration or centrifugation. Due to the hydrophobic nature of organosolv lignin, flotation of organosolv lignin is effective without the use of the collecting and precipitating agents that are required for flotation of kraft lignin. Organocell uses two-stage organosolv with roughly 50% methanol solutions. Sodium hydroxide is added in the second stage at a loading of 30% w/w of the dry wood. The lignin from the second stage is isolated by adding phosphoric acid until a pH of 4.0 is reached. The Alcohol Pulping and Recovery (APR) process treats wood in 3 stages, each using increasingly cleaner solvent. The important process parameters are extraction time, temperature, solvent composition and pH. Pilot plant operation has shown that ethanol pulping produces pulp superior to sulphite pulp at a lower cost. Lignin and hemicellulose are recovered in high yields. In 1987 the APR process was renamed the Alcell process | https://en.wikipedia.org/wiki?curid=30537541 |
Organosolv The process uses aqueous ethanol solutions (40–60% v/v) to delignifying wood at temperatures from 180–210 °C and 2–3.5 MPa. Solvent is recovered with flash evaporation, vapour condensation and vacuum stripping. A demonstration organosolv pulp mill operated in Miramichi, New Brunswick, Canada from 1989 to 1996 using the Alcell process. Repap owned the IP to the process when taken over by hedge funds in 1997. The pilot plant boasted superior environmental performance, excellent bleached pulp, an economically attractive scale of 300 tons/day and commercially attractive by-products. It is said that the technology can be used to exploit small regions of hardwood resource that could not support a modern sized kraft mill. Compagnie Industrielle de la Materière Végétale in France have developed a process where wheat straw is treated with acetic acid / formic acid / water (30/55/15 v/v/v) for 3.5 h at 105 °C under atmospheric pressure. The obtained fibres are screened and bleached. At this conditions the lignin is dissolved and hemicelluloses are hydrolysed to oligo and monosaccharides. Organic acids are collected by concentration of the cooking liquor and then lignin is precipitated by adding water and high pressure filtration. Chempolis Ltd in Oulu, Finland is running a process where common non-wood fibre sources are treated with formic acid in a single-stage process. Process in run for 200–040 min at 110–125 °C. Bleaching is done with hydrogen peroxide at several stages | https://en.wikipedia.org/wiki?curid=30537541 |
Organosolv Chemical recovery is done by evaporation and distillation of the formic acid. The solids consisting of lignin and wood extracticves is dried and may be further processed or burned for energy production. American Science and Technology (AST) based out of Chicago, Illinois, USA, has developed a process which uses a patented second generation process to convert any kind of biomass to more than 10 industrial fine chemicals, organic intermediates and solvents. With a 2 ton/day production facility located in Wausau, Wisconsin, AST can also make high quality pulp, glucose, fructose and lignin. With the AST process, lignocellulosic biomass is treated with sulfuric acid, water, butanol and other organic solvents, water, an organic or inorganic acid, and catalyst for one to three hours at 150 to 200 °C. The results produce fibers that are screened and bleached for paper products. At these conditions, the lignin is dissolved in organic solvent and hemicelluloses are used to produce more organic solvent. Organic solvents are collected by separating water from the cooking liquor and then the lignin is precipitated by adding water, heat, and filtration. The Bloom process was developed at EPFL in Lausanne and is commercialised by Bloom Biorenewables Sàrl. This method is based on a protection chemistry that prevents lignin and C5 sugars condensation. | https://en.wikipedia.org/wiki?curid=30537541 |
Methyl azide is a covalent molecule related to hydrazoic acid and other alkyl azides. It can be prepared by a methylation of sodium azide. The first synthesis was reported in 1905. It decomposes in a first-order reaction: might be a potential precursor in the synthesis of prebiotic molecules via nonequilibrium reactions on interstellar ices initiated by energetic galactic cosmic rays (GCR) and photons. is stable at ambient temperature but may explode when heated. Presence of mercury increases the sensitivity to shock and spark. Incompatible with (dimethyl malonate + sodium methylate); mercury; methanol; sodium azide; dimethyl sulfate; sodium hydroxide; hydrogen azide. When heated to decomposition it emits toxic fumes of NO. | https://en.wikipedia.org/wiki?curid=30540293 |
Alexandru Balaban Alexandru T. Balaban (born April 2, 1931, in Timișoara) is a Romanian chemist who significantly contributed to the fields of organic chemistry, theoretical chemistry, mathematical chemistry, and chemical graph theory. Balaban was born in Timișoara, in the western part of Romania. His parents (Teodor and Florica Balaban) paid a lot of attention to Balaban's education, strongly encouraging his fascination with chemistry. In 1935 his family moved to Bucharest, where Balaban attended elementary school. After World War II, in 1945 they moved to Petroșani, where he finished high school. enrolled the Politehnica University of Bucharest in 1949, where he was awarded a Ph.D. in chemistry on April 2, 1959. The topic of his Ph.D. thesis dealt with the restrictions catalyzed by anhydrous aluminium chloride. For more than forty years, professor Balaban held positions at the Chair of Organic Chemistry of the Politehnica University of Bucharest (assistant professor (1956-1960), associate professor (1961-1966) and full professor (1970-1999)). In addition, he was the head of the Laboratory of Isotopically Labelled Compounds of the Bucharest Institute of Atomic Physics from 1967 to 1974. In 1963, he was elected as Corresponding Member of the Romanian Academy, and in 1990 as Titular Member. From 1967 to 1970, he was appointed as a Senior Research Officer at the Chemistry Division, International Atomic Energy Agency, Vienna, Austria, in charge with radiopharmaceuticals | https://en.wikipedia.org/wiki?curid=30542378 |
Alexandru Balaban From 1995 to 1998, he was acting as Vicepresident of the Romanian Academy. From 1991 to 2012, he was a tenured professor of chemistry at Texas A&M University at Galveston. Since 2013, after his retirement, he has continued as Professor Emeritus at this university. Professor Balaban has been investigating the synthesis and properties of pyrylium salts. He discovered with co-workers a new way of synthesis of pyrylium salts by diacylation of alkenes. This reaction is known as Balaban-Nenitzescu-Praill reaction. Nowadays, Balaban is recognized as a world authority in this field. He wrote the only existing book in this area. Balaban also developed new synthesis of oxazoles by AlCl catalyzed substitution of aromatic compounds with azlactones, followed by dehidratation. In addition, he had been exploring new syntheses of indolizines and of naphthalene derivatives. In order to explain the extraordinary stability of hydrazyls such as 2,2-diphenyl-1-picryl-hydrazyl, Professor Balaban and his co-workers prepared related hydrazyls with lower steric shielding and accordingly lower stability. Then the first push-pull diarylaminyls were synthesized and shown to have stabilities depending both on electronic and steric effects. Another experimental research direction involves the synthesis of chelate compounds having boron as the central atom. Professor Balaban had a permanent interest in theoretical chemistry. He is considered as one of pioneers of the Chemical Graph Theory | https://en.wikipedia.org/wiki?curid=30542378 |
Alexandru Balaban The first book about this interdisciplinary field was edited by Dr. Balaban and appeared in 1976: "Chemical Applications of Graph Theory" (Academic Press, London) and its Chinese translation in 1983. One area in which cubic (or trivalent) graphs play a dominant role is the enumeration of ["n"]annulene valence isomers (CH) where "n" is an even number. With two coauthors, Dr. Balaban published in 1986 on this topic a 3-volume monograph ("Annulenes, Benzo-, Hetero-, Homo-Derivatives and Their Valence Isomers", CRC Press). Some of these valence isomers undergo thermal or pohotochemical automerizations. More recently, Dr. Balaban edited in 1997 a book titled "From Chemical Topology to Three-Dimensional Geometry", Plenum Publishing Corporation, in which various two- and three-dimensional nets were discussed. On using an approach similar to that imagined by Randić for his connectivity index χ, but replacing the adjacency matrix by the distance matrix, and compensating graph-size-increase, a new topological index (TI) "J" was proposed under the name "average distance-based connectivity index"; it is now known as the "Balaban index". Not only is it much less degenerate than all previous TIs, but it allows a simple encoding for the presence of multiple bonds or heteroatoms. Other new TIs were studied: several TIs based on informational descriptors, and triplet-based indices that result from converting matrices into systems of linear equations | https://en.wikipedia.org/wiki?curid=30542378 |
Alexandru Balaban The Lewis acid-catalyzed syntheses of diamondoid hydrocarbons discovered by Schleyer proceed via multiple 1,2-rearrangements. The graph-theoretical analysis of the simplest such reaction involves an ethyl cation with five substituents which undergoes an automerization. This process is characterized by a 20-vertex or a 10-vertex graph depending whether one carbon atom of ethane is or is not labeled. These graphs constitute the first "reaction graphs", in which vertices symbolize reaction intermediates and edges symbolize elementary reaction steeps. Starting from the 10-vertex graph known as the 5-cage or the Petersen graph, Dr. Balaban observed relations among the known cages. Having discovered how a cage with smaller girth "g" was hidden in a cage with girth "g" + 1, Dr. Balaban published a paper on what was later proved to be the first 10-cage, known as the Balaban 10-cage. In 1973, he found the unique 11-cage, known as the Balaban 11-cage, as was proved by mathematicians using a lengthy computer search. Proposals made by Balaban about new possibilities for evaluating the performance of researchers, improving the way citations are used for this purpose (e. g., via the Hirsch index) included the use of author indexes of widely circulated treatises, or modifying the way one considers the impact factors of journals. Honoring invitations to contribute to special issues of journals dedicated to the philosophy of chemistry, Dr | https://en.wikipedia.org/wiki?curid=30542378 |
Alexandru Balaban Balaban published in "Hyle" an essay on how the "Sherlock Holmes principle" (if one eliminates the impossible, then whatever remains, no matter how improbable, must contain the truth) can be implemented by chemical graph theory which allows for instance to find all chemical isomers for a given formula. "Books" (17): author or co-author for 9 books including: "Pyrylium Salts. Syntheses, Reactions and Physical Properties", Academic Press,1982; "Annulenes, Benzo-, Hetero-, Homo-Derivatives and Their Valence Isomers", 3 volumes, CRC Press, 1986; "Modeling of Cancer Genesis and Prevention", CRC Press,1990; editor or co-editor of 8 books including: "Chemical Applications of Graph Theory," Academic Press, 1974 translated into Chinese in 1983"; From Chemical Topology to Three-Dimensional Geometry", Plenum Press,1997; "Science and Technology Management," NATO Science Series, 1987"; Topological Indices and Related Descriptors in QSAR and QSPR," Gordon and Breach, 1999. "Chapters in books edited by other authors" (80). "Articles published in peer-reviewed scientific periodicals" (800). "Patents" (25); three of these are U. S. Patents. Hirsch index: 62 1963, elected as corresponding member of the Romanian Academy, Chemistry Section (youngest member among the other 12-14 corresponding members). In 2013 a special issue of "International Journal of Chemical Modeling" was dedicated to the half-century anniversary for this election | https://en.wikipedia.org/wiki?curid=30542378 |
Alexandru Balaban Due to political circumstances, the promotion to titular member occurred only after the fall of the communist regime, in 1990 1983, elected as member of the World Academy of Theoretical Organic Chemists, Paris. 1993, elected as titular member of the Romanian Academy of Technical Sciences, Bucharest. 1995, elected as titular member of the American-Romanian Academy of Sciences, Arts and Letters. 2001, elected as honorary member of the Hungarian Academy of Sciences, Budapest. 2005, elected as titular member of the International Academy of Mathematical Chemistry, Dubrovnik, Croatia. Membership in Editorial Boards: over 15. 1962, Romanian Academy’s Chemistry Prize 1963, Romanian Order of Labor 1966, Romanian Order of Scientific Merit 1994, Herman Skolnik Award of the Division of Chemical Information of the American Chemical Society 1997, Doctor Honoris Causa, University of Timişoara, Romania 2000, National Order for Faithful Service of the President of Romania 2007, Romanian Academy’s Medal “Costin D. Nenitzescu” for distinguished chemical research results 2007, Distinguished Achievement Award for Research of the Association of Former Students, Texas A&M University | https://en.wikipedia.org/wiki?curid=30542378 |
Porta Alchemica The Alchemical Door, also known as the Alchemy Gate or Magic Portal ( or "Porta Magica"), is a monument built between 1678 and 1680 by Massimiliano Palombara, marquis of Pietraforte, in his residence, the villa Palombara, which was located on the Esquiline hill, near Piazza Vittorio, in Rome. This is the only one of five former gates of the villa that remains; there was a lost door on the opposite side dating them to 1680 and four other lost inscriptions on the walls of the mansion inside the villa. According to a story collected by the erudite Francesco Cancellieri in 1802, a pilgrim named "Stibeum" (from Latin: "stibium", which means "antimony") was hosted in the villa for a night. That night, the pilgrim, identified later by some as the alchemist Giuseppe Francesco Borri—known as "Giustiniano Bono"—, searched the gardens of the villa overnight in search of a mysterious herb capable of concocting gold. Legend held that the next morning he was seen to disappear forever through a door, but left behind a few flakes of gold, the fruits of a successful alchemical transmutation, and a mysterious paper full of puzzling symbols and equations, putatively describing the ingredients and process required. The marquis had these symbols engraved on the five gates of the villa Palombara and on the walls of the mansion, hoping that one day they would be translated | https://en.wikipedia.org/wiki?curid=30544176 |
Porta Alchemica A second legend holds that between 1678 and 1680, the same Giuseppe Francesco Borri along with Athanasius Kircher and Gian Lorenzo Bernini designed and built the gate for the marquis. The marquis Palombara developed a passion for alchemy in 1656, when he visited the alchemical laboratory in Riario Palace, now known as Palazzo Corsini. Patronized by the exiled queen Christina of Sweden, the laboratory was supervised by Pietro Antonio Bandiera and had been visited by Borri and Kircher. This tradition holds the gate was built to memorialize a successful alchemical transmutation that occurred in the Riario Palace. It was rumored that Palombara, Bernini and Kircher were all poisoned on 28 November 1680, probably by Borri, for having revealed the secret formulas through the inscriptions on the gate. Cancellieri published his semi-fanciful account in 1806, including his interpretation of the inscriptions on the Porta Alchimica. His work was published in June 1895 in French by Pietro Bornia as an issue of the periodical "L'Initiation". The particular drawing on the pediment of the gate, with two overlapping triangles and Latin inscriptions, recapitulates the title page in the posthumous 1677 edition—which differed from the title page of the first edition—of the alchemical book "Aureum Saeculum Redivivum" (1621) by Adrian von Mynsicht (known also as Madathanus). In 1747 the emblem was used by Wienner von Sonnenfels in his "Splendor lucis, oder Glanz des Lichts" | https://en.wikipedia.org/wiki?curid=30544176 |
Porta Alchemica Similarly, the lower part of the emblem by von Mynsicht depicting a ""centrum in trigono centri"", was reproduced in a manuscript called the "Geheime Figuren der Rosencreutzer" (1785–88). The same drawing appear in a bookmark possessed by Bérenger Saunière, a parish priest at Rennes-le-Château in 1885. It is suggested as well that the geometrical construction of the gate is similar to that of the 21st emblem of Michael Maier’s "Atalanta Fugiens" (1617). The seven signs are taken from Johannes de Monte-Snyder, "Commentatio de Pharmaco Catholico" published in the "Chymica Vannus" (Amsterdam) in 1666, and follow the sequence of planets, associated to the correspondents metals: Saturn-lead, Jupiter-tin, Mars-iron, Venus-bronze, Mercury, Antinomy and Vitriol. The monument has numerous symbols and inscriptions used in alchemy. The inscriptions are hard to read from the monument itself. Around the circle at top: “The center is in the triangle of the center.” Also: “There are three marvels: God and man, mother and virgin, triune and one.” The Hebrew inscription, Ruach Elohim, means “Spirit of God.” Beneath it: “A dragon guards the entrance of the magic garden of the Hesperides, and, without Hercules, Jason would not have tasted the delights of Colchis.” There are six sigils on the jambs, each with its phrase. Saturn/Lead: “When in your house black crows give birth to white doves, then will you be called wise | https://en.wikipedia.org/wiki?curid=30544176 |
Porta Alchemica ” Jupiter/Tin: “The diameter of the sphere, the tau in the circle, and the cross of the globe bring no joy to the blind.” Mars/Iron: “He who can burn with water and wash with fire makes a heaven of earth and a precious earth of heaven.” Venus/Bronze: “If you make the earth fly upside down, with its wings you may convert torrential waters to stone.” Mercury: “When azoth and fire whiten Latona, Diana comes unclothed.” Antimony: “Our dead son lives, returns from the fire a king, and enjoys occult conjugation.” On the base, Vitriol: “It is an occult work of true wisdom to open the earth, so that it may generate salvation for the people.” In another plate, now lost, was the device VILLAE IANUAM TRANANDO RECLUDENS IASON OBTINET LOCUPLES VELLUS MEDEAE 1680 (Passing by opening the door of the villa, Iason obtained the rich fleece of Medea 1680). And on the doorstep, “SI SEDES NON IS,” an ambiguous quasi-palindrome, meaning both “If you sit, you do not go,” and “If you do not sit, you go.” The standing figures on both sides of the door feature deformed creatures, with short, stout legs and a grotesque bearded face represent a real Egyptian divinity or semi-divinity, called Bes. A patron of the home, childbirth and infants in ancient Egypt, Bes was also known in imperial Rome, where in pre-Christian age several people followed Egyptian cults. Originally the two statues did not belong to Villa Palombara | https://en.wikipedia.org/wiki?curid=30544176 |
Porta Alchemica They were found somewhere near the Quirinal Hill, where in ancient times stood a large temple dedicated to the Egyptian gods Isis and Serapis; century after century, many of its rich decorations, reliefs, small obelisks, etc. were unearthed, and were relocated in different parts of the city. During the works for the opening of piazza Vittorio, in 1888 also these statues were moved from their original location to the Porta Alchemica. On the door On Massimiliano Palombara | https://en.wikipedia.org/wiki?curid=30544176 |
Kondo insulator In solid-state physics, Kondo insulators (also referred as Kondo semiconductors and heavy fermion semiconductors) are understood as materials with strongly correlated electrons, that open up a narrow band gap (in the order of 10 meV) at low temperatures with the chemical potential lying in the gap, whereas in heavy fermions the chemical potential is located in the conduction band. The band gap opens up at low temperatures due to hybridization of localized electrons (mostly f-electrons) with conduction electrons, a correlation effect known as the Kondo effect. As a consequence, a transition from metallic behavior to insulating behavior is seen in resistivity measurements. The band gap could be either direct or indirect. Most studied Kondo insulators are FeSi, CeBiPt, SmB, YbB, and CeNiSn. In 1969, Menth "et al." found no magnetic ordering in SmB down to 0.35 K and a change from metallic to insulating behavior in the resistivity measurement with decreasing temperature. They interpreted this phenomenon as a change of the electronic configuration of Sm. Gabriel Aeppli and Zachary Fisk found a descriptive way to explain the physical properties of CeBiPt and CeNiSn in 1992. They called the materials Kondo insulators, showing Kondo lattice behavior near room temperature, but becoming semiconducting with very small energy gaps (a few Kelvin to a few tens of Kelvin) when decreasing the temperature. At high temperatures the localized f-electrons form independent local magnetic moments | https://en.wikipedia.org/wiki?curid=30555998 |
Kondo insulator According to the Kondo effect, the dc-resistivity of Kondo insulators shows a logarithmic temperature-dependence. At low temperatures, the local magnetic moments are screened by the sea of conduction electrons, forming a so-called Kondo resonance. The interaction of the conduction band with the f-orbitals results in a hybridization and an energy gap formula_1. If the chemical potential lies in the hybridization gap, an insulating behavior can be seen in the dc-resistivity at low temperatures. In recent times, angle-resolved photoemission spectroscopy experiments provided direct imaging of band-structure, hybridization and flat band topology in Kondo insulators and related compounds. | https://en.wikipedia.org/wiki?curid=30555998 |
SAF 2205 SAF 2205, also known as Sandvik SAF 2205, is a Sandvik-owned trademark for a 22Cr duplex (ferritic-austenitic) stainless steel. "SAF" derives from "S"andvik "A"ustenite "F"errite. The nominal chemical composition of is 22% chromium, 5% nickel, 3.2% molybdenum and other alloying elements such as nitrogen and manganese. The UNS designation for is S31803/S32205 and the EN steel no. is 1.4462. or Duplex 2205 is often used as an alternative to expensive 904L stainless steel owing to similar properties but cheaper ingredients. Duplex stainless steel is available in multiple forms like bars, billets, pipes, tubes, sheets, plates and even processed to fittings and flanges. Typical properties of duplex stainless steel are: Duplex 2205 Stainless Steel (both austenitic and ferritic) is used in applications that require strength and good corrosion resistance. S31803 was endorsed in year 1996 whereas it underwent number of changes that led to discovery of UNS S32205 which is more widely used. Possible alternates for are 904L Stainless Steel, UR52N+, 6%Mo and 316L. Applications of are in the following industries: | https://en.wikipedia.org/wiki?curid=30556666 |
Alternative Splicing Annotation Project (ASAP) was a database for alternative splicing data maintained by the University of California from 2003 to 2013. The purpose of ASAP was to provide a source for data mining projects by consolidating the information generated by genomics and proteomics researchers. | https://en.wikipedia.org/wiki?curid=30558194 |
Run-around coil A run-around coil is a type of energy recovery heat exchanger most often positioned within the supply and exhaust air streams of an air handling system, or in the exhaust gases of an industrial process, to recover the heat energy. Generally, it refers to any intermediate stream used to transfer heat between two streams that are not directly connected for reasons of safety or practicality. It may also be referred to as a run-around loop, a pump-around coil or a liquid coupled heat exchanger. A typical run-around coil system comprises two or more multi-row finned tube coils connected to each other by a pumped pipework circuit. The pipework is charged with a heat exchange fluid, normally water, which picks up heat from the exhaust air coil and gives up heat to the supply air coil before returning again. Thus heat from the exhaust air stream is transferred through the pipework coil to the circulating fluid, and then from the fluid through the pipework coil to the supply air stream. The use of this system is generally limited to situations where the air streams are separated and no other type of device can be utilised since the heat recovery efficiency is lower than other forms of air-to-air heat recovery. Gross efficiencies are usually in the range of 40 to 50%, but more significantly seasonal efficiencies of this system can be very low, due to the extra electrical energy used by the pumped fluid circuit | https://en.wikipedia.org/wiki?curid=30560133 |
Run-around coil The fluid circuit containing the circulating pump also contains an expansion vessel, to accommodate changes in fluid pressure. In addition, there is a fill device to ensure the system remains charged. There are also controls to bypass and shut down the system when not required, and other safety devices. Pipework runs should be as short as possible, and should be sized for low velocities to minimize frictional losses, hence reducing pump energy consumption. It is possible to recover some of this energy in the form of heat given off by the motor if a glandless pump is used, where a water jacket surrounds the motor stator, thus picking up some of its heat. The pumped fluid will have to be protected from freezing, and is normally treated with a glycol based anti-freeze. This also reduces the specific heat capacity of the fluid and increases the viscosity, increasing pump power consumption, further reducing the seasonal efficiency of the device. For example, a 20% glycol mixture will provide protection down to , but will increase system resistance by 15%. For the finned tube coil design, there is a performance maximum corresponding to an eight- or ten-row coil, above this the fan and pump motor energy consumption increases substantially and seasonal efficiency starts to decrease. The main cause of increased energy consumption lies with the fan, for the same face velocity, fewer coil rows will decrease air pressure drop and increase water pressure drop | https://en.wikipedia.org/wiki?curid=30560133 |
Run-around coil The total energy consumption will usually be less than that for a greater number of coil rows with higher air pressure drops and lower water pressure drops. Normally the heat transfer between airstreams provided by the device is termed as 'sensible', which is the exchange of energy, or enthalpy, resulting in a change in temperature of the medium (air in this case), but with no change in moisture content. | https://en.wikipedia.org/wiki?curid=30560133 |
Sample injector A sample injector is a device used in conjunction with injecting samples into high-performance liquid chromatography (HPLC) or similar chromatography apparati. | https://en.wikipedia.org/wiki?curid=30577297 |
Bengt Nordén Bengt Johan Fredrik Nordén (born May 15, 1945 in Lund) is a Swedish chemist. graduated 1967 with a Master of Science degree in chemistry, theoretical physics and mathematics from Lund University and was awarded his Ph.D. in 1971 from Lund University where he became Associate Professor of Inorganic Chemistry in 1972. In 1979 he was appointed to the Chair Professorship of Physical Chemistry of Chalmers University of Technology. Nordén's research concerns optical Linear dichroism spectroscopy of macroscopically oriented, mainly bio-macromolecular systems. He has developed novel DNA-binding ligands, such as bis-intercalating compounds and peptide nucleic acids (PNA), and demonstrated DNA-ligand reorganisations between groove-binding and intercalation binding geometries involving extreme activation energies and recognition due to kinetic (in contrast to thermodynamic) selection. His method “Site Specific Linear Dichroism by Molecular Replacement” methodology applied to DNA complexes with RecA and Rad51 recombination proteins has revealed details of the recombination mechanism and is also applied to study structure of membrane proteins in a true membrane environment. Nordén was councilor for Science and Technology to the Swedish Government in 1991-1994. He was Chairman of the selection committee for the European Science Foundation’s Young Research Investigator Awards 2003-2006; chemistry editor of the Swedish National Encyclopedia, Chairman of the Chemistry Section of the Swedish Research Council 1996-2000 | https://en.wikipedia.org/wiki?curid=30579949 |
Bengt Nordén He is currently Chair of the Nanyang Technological University Research Council (Singapore) and Chair of the board of editors of The Quarterly reviews of biophysics . Nordén is a member of the Royal Swedish Academy of Sciences since 1991 and was member of the Nobel Committee for Chemistry from 1995 to 2004, and the Committee's chairman from 2000 to 2003 and the Academy's Chemistry Section chairman 2004-2009. He is a member of the Royal Swedish Academy of Engineering Sciences, The Royal Physiographic Society in Lund, The Royal Society of Arts and Sciences in Gothenburg (Kungliga Vetenskaps- och Vitterhetssamhället i Göteborg), The National Academy of Sciences of Germany (German Academy of Sciences Leopoldina), the Swedish Academy of Engineering Sciences in Finland, The Norwegian Academy of Science, The Finnish Society of Science and Letters, and The Academy of Sciences for the Developing World (TWAS). Nordén is founder of Molecular Frontiers, a global organization with objective to early identify breakthroughs in science and to stimulate young people's interests in science. Molecular Frontiers has in its Advisory Board many very research active Nobel Laureates. | https://en.wikipedia.org/wiki?curid=30579949 |
Alternative Splicing and Transcript Diversity database The (ASTD) was a database of transcript variants maintained by the European Bioinformatics Institute from 2008 to 2012. It contained transcription initiation, polyadenylation and splicing variant data. | https://en.wikipedia.org/wiki?curid=30594071 |
ChimerDB is a database of fusion sequences. currently consists of three searchable datasets. | https://en.wikipedia.org/wiki?curid=30594108 |
DBASS3/5 DBASS3 and DBASS5 is a database of new exon boundaries induced by pathogenic mutations in human disease genes. | https://en.wikipedia.org/wiki?curid=30594153 |
Maneb is a fungicide and a polymeric complex of manganese with the ethylene bis(dithiocarbamate) anionic ligand. It can be also used to create a toxin-based animal model of Parkinson's disease, usually in primates. It was included in a pesticide ban proposed by the Swedish Chemicals Agency and approved by the European Parliament on January 13, 2009. | https://en.wikipedia.org/wiki?curid=30594193 |
ECgene is a database of genomic annotations taking alternative splicing events into consideration. | https://en.wikipedia.org/wiki?curid=30597895 |
Oil waxing occurs when heating oil begin to gel, and before it has become actually too viscous to flow at all in the heating system oil piping, wax particles (wax platelets or little spheres of wax or in some articles, alkane "wax crystals") have already begun to form in the fuel. The wax platelets form first from the long hydrocarbon chains which are a component in the heating oil (or diesel fuel). It is these waxy particles that can clog an oil line or even an oil-fired heating boiler, furnace, or water heater. | https://en.wikipedia.org/wiki?curid=30598471 |
Alpha-Endorphin α-Endorphin is an endogenous opioid peptide with a length of 16 amino acids, and the amino acid sequence: Tyr-Gly-Gly-Phe-Met-Thr-Ser-Glu-Lys-Ser-Gln-Thr-Pro-Leu-Val-Thr. | https://en.wikipedia.org/wiki?curid=30605783 |
Gamma-Endorphin γ-Endorphin is an opioid peptide that is characterized by the presence of 17 amino acids. The first 16 amino acids are identical to α-endorphin with Leucine added at the end; or alternatively, γ-Endorphin is equal to the first 17 amino acids of beta-Endorphin. Similar to other endorphins, research focusing upon γ-endorphin has been ongoing since its discovery in the 1970s. Yet, most of the information about the substance’s exact role within the body is speculation that has yet to be proven. Some studies have indicated, however, that the polypeptide has antipsychotic effects on a certain category of patients suffering from schizophrenia, while others suggest that gamma-endorphin may act to help regulate blood pressure. Further research is needed, but if γ-endorphin does indeed possess such characteristics, the substance could eventually be utilized as a useful means of medical treatment. | https://en.wikipedia.org/wiki?curid=30605803 |
SAF 2507 SAF 2507, also known as Sandvik SAF 2507, is a Sandvik-owned trademark for a 25Cr duplex (ferritic-austenitic) stainless steel. The nominal chemical composition of is 25% Chromium, 7% Nickel, 4% Molybdenum and other alloying elements such as Nitrogen and Manganese. The UNS designation for is S32750 and the EN steel no. is 1.4410. "SAF" derives from "S"andvik "A"ustenite "F"errite. Typical properties of duplex stainless steel are: | https://en.wikipedia.org/wiki?curid=30609950 |
Brightray is a nickel-chromium alloy that is noted for its resistance to erosion by gas flow at high temperatures. It was used for hard-facing the exhaust valve heads and seats of petrol engines, particularly aircraft engines from the 1930s onwards. It was developed by Henry Wiggin and Co at Birmingham. As well as its use as a coating, it is also used in wire and strip form for electrical heating elements. The original alloy was composed of 80% nickel / 20% chromium. This alloy is still in use today as "S" and can be used at temperatures up to 1050°C. Several other variants are now available. These include nickel-iron-chromium "F" that offers better resistance to both reducing and oxidizing environments. "C" is a nickel-chromium alloy with rare-earth additions to extend its lifetime under fluctuating temperatures, particularly with heating elements that are being continually switched on and off. | https://en.wikipedia.org/wiki?curid=30625834 |
Helmut Schwarz (born 6 August 1943) is a German organic chemist. He has been a professor of chemistry at the Technische Universität Berlin since 1978, and president of the Alexander von Humboldt Foundation since January 2008. In 2018, he was elected a foreign associate of the U.S. National Academy of Sciences. first learned to be a chemical technician and then went on to study chemistry in Berlin Chemie. He completed his studies in 1971 and obtained his PhD in 1972 and his Habilitation in 1974 under . He pursued post-doctoral work at the Massachusetts Institute of Technology (MIT) and in the UK, after which he became a professor at the TU Berlin in 1978. Schwarz studies chemical reactions, specifically gas phase chemistry of ionic and radical organic species. He is furthermore working on advancing the analytical capabilities of mass spectrometry. From 2010 to 2015 he was president of the German Academy of Researchers Leopoldina and he is a member of acatech. Schwarz was an editor of the International Journal of Mass Spectrometry from 1983 to 2010 and between 1990 and 1994 he was editor of Chemischen Berichte. He was part of the editorial board of Mass Spectrometry Reviews from 1990 to 2003, of Helvetica Chimica Acta (1990 to 2002), and of the Journal of the American Chemical Society (2007 to 2015). He is a member of the following societies He has received numerous awards and honors, among them | https://en.wikipedia.org/wiki?curid=30630090 |
Jurin's law Jurin's law, or capillary rise, is the simplest analysis of capillary action—the induced motion of liquids in small channels—and states that the maximum height of a liquid in a capillary tube is inversely proportional to the tube's diameter. Capillary action is one of the most common fluid mechanical effects explored in the field of microfluidics. is named after James Jurin, who discovered it between 1718 and 1719. His quantitative law suggests that the maximum height of liquid in a capillary tube is inversely proportional to the tube's diameter. The difference in height between the surroundings of the tube and the inside, as well as the shape of the meniscus, are caused by capillary action. The mathematical expression of this law can be derived directly from hydrostatic principles and the Young–Laplace equation. allows the measurement of the surface tension of a liquid and can be used to derive the capillary length. The law is expressed as where It is only valid if the tube is cylindrical and has a radius ("r") smaller than the capillary length (formula_2). In terms of the capillary length, the law can be written as For a water-filled glass tube in air at standard conditions for temperature and pressure, at 20 °C, , and . For these values, the height of the water column is Thus for a radius glass tube in lab conditions given above, the water would rise an unnoticeable . However, for a radius tube, the water would rise , and for a radius tube, the water would rise | https://en.wikipedia.org/wiki?curid=30639331 |
Jurin's law Capillary action is used by many plants to bring up water from the soil. For tall trees (larger than ~10 m (32 ft)), other processes like osmotic pressure and negative pressures are also important. During the 15th century, Leonardo da Vinci was one of the first to propose that mountain streams could result from the rise of water through small capillary cracks. It is later, in the 17th century, that the theories about the origin of capillary action begin to appear. Jacques Rohault erroneously supposed that the rise of the liquid in a capillary could be due to the suppression of air inside and the creation of a vacuum. The astronomer Geminiano Montanari was one of the first to compare the capillary action to the circulation of sap in plants. Additionally, the experiments of Giovanni Alfonso Borelli determined in 1670 that the height of the rise was inversely proportional to the radius of the tube. Francis Hauksbee, in 1713, refuted the theory of Rohault through a series of experiments on capillary action, a phenomenon that was observable in air as well as in vacuum. Hauksbee also demonstrated that the liquid rise appeared on different geometries (not only circular cross sections), and on different liquids and tube materials, and showed that there was no dependence on the thickness of the tube walls. Isaac Newton reported the experiments of Hauskbee in his work "Opticks" but without attribution | https://en.wikipedia.org/wiki?curid=30639331 |
Jurin's law It was the English physiologist James Jurin, who finally in 1718 confirmed the experiments of Borelli and the law was named in his honour. The height formula_5 of the liquid column in the tube is constrained by the hydrostatic pressure and by the surface tension. The following derivation is for a liquid that rises in the tube; for the opposite case when the liquid is below the reference level, the derivation is analogous but pressure differences may change sign. Above the interface between the liquid and the surface, the pressure is equal to the atmospheric pressure formula_6. At the meniscus interface, due to the surface tension, there is a pressure difference of formula_7, where formula_8is the pressure on the convex side; and formula_9 is known as Laplace pressure. If the tube has a circular section of radius formula_10, and the meniscus has a spherical shape, the radius of curvature is formula_11, where formula_12 is the contact angle. The Laplace pressure is then calculated according to the Young-Laplace equation:formula_13where formula_14 is the surface tension. Outside and far from the tube, the liquid reaches a ground level in contact with the atmosphere. Liquids in communicating vessels have the same pressures at the same heights, so a point formula_15, inside the tube, at the same liquid level as outside, would have the same pressure formula_16 | https://en.wikipedia.org/wiki?curid=30639331 |
Jurin's law Yet the pressure at this point follows a vertical pressure variation as where formula_18 is the gravitational acceleration and formula_19 the density of the liquid. This equation means that the pressure at point formula_15 is the pressure at the interface plus the pressure due to the weight of the liquid column of height formula_5. In this way, we can calculate the pressure at the convex interface formula_22 The hydrostatic analysis shows that formula_23, combining this with the Laplace pressure calculation we have:formula_24solving for formula_5 returns Jurin's law. | https://en.wikipedia.org/wiki?curid=30639331 |
Struve–Sahade effect The (S–S effect) occurs in a double-lined spectroscopic binary star system when the strength of the spectral lines of the components varies during the orbital motion. A spectroscopic binary is called double-lined when the absorption lines of both stars can be observed with a spectroscope. As each member of the star system approaches the observer in turn, the absorption lines of that star are shifted toward the blue end of the optical spectrum by the Doppler effect. Likewise, as a star moves away, its lines are shifted toward the red end of the spectrum. Each of these absorption lines has a characteristic strength that depends on the physical properties of the photosphere. The occurs when these lines become anomalously weaker as a star's spectrum is red-shifted, and stronger when it is blue-shifted, most noticeable in the secondary component. This effect is observed in the bright naked eye binary Spica, which consists of two class B stars, and pairs of massive O class stars such as AO Cassiopeiae and HD 93403. The was first reported by Otto Struve in 1937. It became important because the effect called into question the values of parameters such as mass and luminosity ratios in massive spectroscopic binary systems. In 1950, Struve attempted to explain the effect as the result of streams of gas trailing behind the secondary star, causing the star to be obscured when the star was moving away | https://en.wikipedia.org/wiki?curid=30642120 |
Struve–Sahade effect In 1959, Jorge Sahade produced a model where a gaseous stream extended from the primary to the secondary member of the binary, and the opacity of this stream produced the weakening of the absorption lines. The effect then became known as the Struve–Sahade effect. In 1997, Gies and colleagues provided an alternative explanation, arguing that the collision between the stellar winds from the two stars results in a bow shock that is deflected by the Coriolis force, placing it in an obscuring position along the line of sight to the secondary star. Other hypotheses have since been created to explain this effect, but models still do not fully reproduce the observed line strengths. | https://en.wikipedia.org/wiki?curid=30642120 |
Modified active gas sampling Modified Active Gas Sampling (MAGS) is an environmental engineering assessment technique which rapidly detects unsaturated soil source areas impacted by volatile organic compounds. The technique was developed by HSA Engineers & Scientists in Fort Myers, Florida in 2002, led by Richard Lewis, Steven Folsom, and Brian Moore. It is being used all over the United States, and has been adopted by the state of Florida in its Dry-cleaning Solvent Cleanup Program. MAGS involves the extraction and analysis of soil vapor from a piezometer screened through the unsaturated soil column for the purpose of locating unsaturated zone source material. According to the MAGS Manual, written by HSA and adopted by the Florida Department of Environmental Protection, MAGS is performed "by utilizing a typical regenerative blower fitted to a temporary soil vapor extraction well, [such that]a large volume of soil can be assessed with a limited number of samples. While lacking the resolution of traditional soil sampling methods (e.g., discrete soil sampling, low flow active gas sampling, etc.), the statistical representativeness (in the sense of sample coverage) of MAGS results versus traditional methods is much greater. Moreover, the results of the assessment provide useful transport and exposure assessment information over traditional techniques. Lastly, MAGS is effective as both an initial site assessment and remedial assessment tool, in that, MAGS directly yields data required for remedial design | https://en.wikipedia.org/wiki?curid=30643318 |
Modified active gas sampling " MAGS is an alternative to discrete and composite soil sampling. MAGS, while it does not describe the sample with as much precision as the previously mentioned sampling methods, is more powerful statistically: it represents a larger area of a site which is more useful in determining the presence of a compound. Besides increasing the accuracy in identifying the presence compounds in the soil, MAGS also can quickly and accurately narrow down the location and spread of the compounds after a few trials. Once the location has been determined, more thorough and traditional soil borings can be done in the identified location, instead of sampling a whole site. HSA found particular success using the technique at solvent-impacted sites that were showing signs of rebound after initial remediation efforts. These rebounds are commonly the result of multiple (relatively small) release areas that had not been previously discovered with discrete soil sampling. MAGS can be useful in detecting how effectively the site had been cleaned up post-remediation. HSA Engineers & Scientists considered patenting MAGS technology, but decided to trademark MAGS instead, asking that those who use the technique credit the firm. In 2009, HSA was recognized by the Environmental Business Journal with a Technology Merit Award in the category of remediation for the invention of MAGS technology. | https://en.wikipedia.org/wiki?curid=30643318 |
Ruff degradation In 1898, Otto Ruff published his work on the transformation of D-Glucose to D-Arabinose later called the Ruff degradation. In this reaction, D-Glucose is converted to D-Arabinose . In this reaction, the terminal aldehyde group is converted to a carboxylic acid group, using selective oxidation of the aldehyde using Bromine water and then converted to gluconate ion. Next, Fe(OAc) with 30% of HO is added. Thus COO- ion will form CO2 and a stereo selective compound will form. And below -CH2OH will convert to -CHO group through the reduction of iron from its +3 state to +2 state, thus forming D-Arabinose. shortens an aldose chain by removing one carbon | https://en.wikipedia.org/wiki?curid=30647223 |
Tin-silver-copper (SnAgCu, also known as SAC), is a lead-free (Pb-free) alloy commonly used for electronic solder. The tin-silver-copper alloy has been the prevailing alloy system used to replace tin-lead because it is near eutectic, with adequate thermal fatigue properties, strength, and wettability. Lead-free solder is gaining much attention as the environmental effects of lead in industrial products is recognized, and as a result of Europe’s RoHS legislation to remove lead and other hazardous materials from electronics. Japanese electronics companies have also looked at Pb-free solder for its industrial advantages. Typical alloys are 3–4% silver, 0.5–0.7% copper, and the balance (95%+) tin. For example, the common "SAC305" solder is 3.0% silver and 0.5% copper. Cheaper alternatives with less silver are used in some applications, such as SAC105 and SAC0307 (0.3% silver, 0.7% copper), at the expense of a somewhat higher melting point. SAC alloys are the main choice for lead-free surface-mount technology (SMT) assembly in the electronics industry. SMT is a process where components of circuit assemblies are mounted directly onto the surface of a printed circuit board and soldered in place. SMT has largely replaced “through-hole technology” where components are fitted with wire leads into holes in the circuit board | https://en.wikipedia.org/wiki?curid=30655042 |
Tin-silver-copper In 2000, there were several lead-free assemblies and chip products initiatives being driven by the Japan Electronic Industries Development Association (JEIDA) and Waste Electrical and Electronic Equipment Directive (WEEE). These initiatives resulted in tin-silver-copper alloys being considered and tested as lead-free solder ball alternatives for array product assemblies. In 2003, tin-silver-copper was being used as a lead-free solder. However, its performance was criticized because it left a dull, irregular finish and it was difficult to keep the copper content under control. In 2005, tin-silver-copper alloys constituted approximately 65% of lead-free alloys used in the industry and this percentage has been increasing. Large companies such as Sony and Intel switched from using lead-containing solder to a tin-silver-copper alloy. The process requirements for SAC solders (Pb-free) and Sn-Pb solders are different both materially and logistically for electronic assembly. In addition, the reliability of Sn-Pb solders is well established, while SAC solders are still undergoing study, (though much work has been done to justify the use of SAC solders, such as the iNEMI Lead Free Solder Project). One important difference is that Pb-free soldering requires higher temperatures and increased process control to achieve the same results as that of the tin-lead method. The melting point of SAC alloys is 217–220 °C, or about 34 °C higher than the melting point of the eutectic tin-lead (63/37) alloy | https://en.wikipedia.org/wiki?curid=30655042 |
Tin-silver-copper This requires peak temperatures in the range of 235–245 °C to achieve wetting and wicking. Some of the components susceptible to SAC assembly temperatures are electrolytic capacitors, connectors, opto-electronics, and older style plastic components. However, a number of companies have started offering 260 °C compatible components to meet the requirements of Pb-free solders. iNEMI has proposed that a good target for development purposes would be around 260 °C. Also, SAC solders are alloyed with a larger number of metals so there is the potential for a far wider variety of intermetallics to be present in a solder joint. These more complex compositions can result in solder joint microstructures that are not as thoroughly studied as current tin-lead solder microstructures. These concerns are magnified by the unintentional use of lead-free solders in either processes designed solely for tin-lead solders or environments where material interactions are poorly understood. For example, the reworking of a tin-lead solder joint with Pb-free solder. These mixed-finish possibilities could negatively impact the solder’s reliability. SAC solders have outperformed high-Pb solders C4 joints in ceramic ball grid array (CBGA) systems, which are ball-grid arrays with a ceramic substrate. The CBGA showed consistently better results in thermal cycling for Pb-free alloys. The findings also show that SAC alloys are proportionately better in thermal fatigue as the thermal cycling range decreases | https://en.wikipedia.org/wiki?curid=30655042 |
Tin-silver-copper SAC performs better than Sn-Pb at the less extreme cycling conditions. Another advantage of SAC is that it appears to be more resistant to gold embrittlement than Sn-Pb. In test results, the strength of the joints is substantially higher for the SAC alloys than the Sn-Pb alloy. Also, the failure mode is changed from a partially brittle joint separation to a ductile tearing with the SAC. | https://en.wikipedia.org/wiki?curid=30655042 |
Triethylgallium Triethylgallium, Ga(CH), or TEGa, is a metalorganic source of gallium for metalorganic vapour phase epitaxy (MOVPE) of compound semiconductors. TEGa is a clear, colorless, pyrophoric liquid and should be handled with caution. TEGa can be a useful alternative to trimethylgallium in the metalorganic vapour phase epitaxy of compound semiconductors because films grown using TEGa have been shown to have a lower carbon impurity concentration. | https://en.wikipedia.org/wiki?curid=30669405 |
Quadrupole splitting is an example of a hyperfine interaction found in gamma-ray spectroscopy, in the circumstance where nuclei with a non-radially-symmetric shape (that is, with a spin quantum number greater than 1/2) are found immersed in an external electric field gradient. It splits a state into two, producing a doublet in the Mössbauer spectrum, and the separation between the states can be used to measure the sign and strength of this electric field gradient, which is affected by the chemical environment of the nuclei. | https://en.wikipedia.org/wiki?curid=30677625 |
Toxophore A toxophore is the chemical group that produces the toxic effect in a toxin molecule: commonly used in pharmaceutical and pesticide sciences. | https://en.wikipedia.org/wiki?curid=30678506 |
Zeeman slower <nowiki></nowiki> A or Zeeman decelerator is a scientific apparatus that is commonly used in quantum optics to cool a beam of atoms from room temperature or above to a few kelvins. At the entrance of the the average speed of atoms is on the order of a few hundred m/s. The spread of velocity is also in the order of a few hundred m/s. Final speed at the exit of the slower is few 10 m/s with an even smaller spread. A consists of a cylinder, through which the beam travels, a pump laser that is shone on the beam in the direction opposite to the beam's motion, and a magnetic field (commonly produced by a solenoid-like coil) that points along the symmetry axis of the cylinder and varies spatially along the axis of the cylinder. The pump laser, which is required to be near-resonant to an atomic or molecular transition, Doppler slows a certain velocity class within the velocity distribution of the beam. The spatially varying Zeeman shift of the resonant frequency enables lower and lower velocity classes to be resonant with the laser, as the atomic or molecular beam propagates along the slower, hence slowing the beam. It was first developed by William D. Phillips (who was awarded the Nobel Prize in Physics for this discovery in 1997 together with Steven Chu and Claude Cohen-Tannoudji ""for development of methods to cool and trap atoms with laser light"") and Harold J. Metcalf | https://en.wikipedia.org/wiki?curid=30682536 |
Zeeman slower The achievement of these low temperatures led the way for the experimental realisation of Bose–Einstein condensation, and a can be part of such an apparatus. According to the principles of Doppler cooling, an atom modelled as a two-level atom can be cooled using a laser. If it moves in a specific direction and encounters a counter-propagating laser beam resonant with its transition, it is very likely to absorb a photon. The absorption of this photon gives the atom a "kick" in the direction that is consistent with momentum conservation and brings the atom to its excited state. However, this state is unstable and some time later the atom decays back to its ground state via spontaneous emission (after a time on the order of nanoseconds, for example in Rubidium 87 the excited state of the D2 transition has a lifetime of 26.2 ns). The photon will be reemitted (and the atom will again increase its speed), but its direction will be random. When averaging over a large number of these processes applied to one atom, one sees that the absorption process decreases the speed always in the same direction (as the absorbed photon comes from a monodirectional source), whereas the emission process does not lead to any change in the speed of the atom because the emission direction is random. Thus the atom is being effectively slowed down by the laser beam. There is nevertheless a problem in this basic scheme because of the Doppler effect | https://en.wikipedia.org/wiki?curid=30682536 |
Zeeman slower The resonance of the atom is rather narrow (on the order of a few megaHertz), and after having decreased its momentum by a few recoil momenta, it is no longer in resonance with the pump beam because in its frame, the frequency of the laser has shifted. The uses the fact that a magnetic field can change the resonance frequency of an atom using the Zeeman effect to tackle this problem. The average acceleration (due to many photon absorption events over time) of an atom with mass, formula_1, a cycling transition with frequency, formula_2, and linewidth, formula_3, that is in the presence of a laser beam that has wavenumber, formula_4, and intensity formula_5 (where formula_6 is the saturation intensity of the laser) is In the rest frame of the atoms with velocity, formula_8, in the atomic beam, the frequency of the laser beam is shifted by formula_9. In the presence of a magnetic field formula_10, the atomic transition is Zeeman shifted by an amount formula_11 (where formula_12 is the magnetic moment of the transition). Thus, the effective detuning of the laser from the zero-field resonant frequency of the atoms is The atoms for which formula_14 will experience the largest acceleration, namely where formula_16 and formula_17. The most common approach is to require that we have a magnetic field profile that varies in the formula_18 direction such that the atoms experience a constant acceleration formula_15 as they fly along the axis of the slower | https://en.wikipedia.org/wiki?curid=30682536 |
Zeeman slower It has been recently shown however, that a different approach yields better results. In the constant deceleration approach we get: where formula_22 is the maximum velocity class that will be slowed; all the atoms in the velocity distribution that have velocities formula_23 will be slowed, and those with velocities formula_24 will not be slowed at all. The parameter formula_25 (which determines the required laser intensity) is normally chosen to be around .5. If a were to be operated with formula_26, then after absorbing a photon and moving to the excited state, the atom would then preferentially re-emit a photon in the direction of the laser beam (due to stimulated emission) which would counteract the slowing process. The required form of the spatially inhomogeneous magnetic field as we showed above has the form This field can be realized a few different ways. The most popular design requires wrapping a current carrying wire with many layered windings where the field is strongest (around 20-50 windings) and few windings where the field is weak. Alternative designs include: a single layer coil that varies in the pitch of the winding. an array of permanent magnets in various configurations, The is usually used as a preliminary step to cool the atoms in order to trap them in a magneto-optical trap. Thus it aims at a final velocity of about 10 m/s (depending on the atom used), starting with a beam of atoms with a velocity of a few hundred meters per second | https://en.wikipedia.org/wiki?curid=30682536 |
Zeeman slower The final speed to be reached is a compromise between the technical difficulty of having a long and the maximal speed allowed for an efficient loading into the trap. A limitation of setup can be the transverse heating of the beam. It is linked to the fluctuations of the speed along the three axis around its mean values, since the final speed was said to be an average over a large number of processes. These fluctuations are linked to the atom having a Brownian motion due to the random reemission of the absorbed photon. They may cause difficulties when loading the atoms in the next trap. | https://en.wikipedia.org/wiki?curid=30682536 |
University School of Chemical Technology (USCT) is one of the constituent school of Guru Gobind Singh Indraprastha University, ‘A’ Grade accreditation from NAAC, the University is recognized by the University Grants Commission (UGC) India under section 12B of UGC Act. The University was established by government of NCT of Delhi under the provisions of Guru Gobind Singh Indraprastha University Act, 1998. It is located at Dwarka, New Delhi. The old campus of the University was situated in Kashmere Gate, New Delhi. USCT was established in 1998, the same year when other constituent schools were formed. It was a bold step by the University to start the University School of Chemical Technology, the only one of its kind in this part of the country after IIT Delhi. The recognizes the importance of Chemical Industry and the need for trained manpower. The school has been established with the twin objective of generating effective trained professionals and to keep pace with R&D activities of this fast changing field of Chemical Technology. The School has been established to design and implement courses with the aim of imparting quality education. School offers the following programme, in the field of Chemical Engineering:- From 2013 onwards the school has also started offering : The dual degree programs are offered under a 4+2 scheme, wherein a student can exit at the end of four years with a B.Tech degree. The B.Tech/M.Tech | https://en.wikipedia.org/wiki?curid=30690380 |
University School of Chemical Technology (Integrated) programme being offered by the school is based on the pattern of IITs and other national and international institutions of repute. The well-structured programme is meant to impart comprehensive knowledge of various core chemical engineering subjects, inter- disciplinary courses in biotechnology, Management Studies through electives, and Industrial exposure through practical training in Laboratories and Industrial Units. Admission for the four year B.Tech course is done on the basis of merit; strictly based on the Common Entrance Exam of GGSIPU - B.Tech Program and for M.Tech program either the score of GATE or entrance exam based merit is required. has modern class rooms that are equipped with overhead projectors for interactive sessions in the class. Internet and Intranet facilities are also provided. The school also provides state of the art seminar hall for interactive seminar and events, both for curricular and extra-curricular activities. University Information and Resource Centre has been established by the University to provide books, journals, news-papers, magazines, and periodicals for references. Laboratories in the department include pilot plants that cover most of the unit operations covered in the curriculum and hence strengthen the fundamentals of Chemical Engineering. The teaching aids also include modern control techniques and software like ASPEN, FLUENT, PHAST, MATLAB, POLY-MATH. Hostel facility is available for both girls and boys, single room being allotted to an individual | https://en.wikipedia.org/wiki?curid=30690380 |
University School of Chemical Technology University canteen is open during the college hours. The university has the major sports facilities including Football, Volleyball, Basketball, Lawn Tennis, Table Tennis, Badminton, Tug of war, Cricket, Athletics. Health care centre remains open during college hours and doctors and specialists are available. Shops and food outlets like Amul, Nescafe, Mother Dairy and Kendriya Bhandaar are there in the University campus. Indian Bank and ATM is also available. The students of USCT actively participate in various competitions held by the university, IITs and other chemical organisations. The REACT Society of USCT is an active organization that has been formed to advance the objectives of the student community of the to stimulate interaction and interest between faculty and students of all academic areas in the USCT. It aims at providing academic outreach as well as ties to the local industries and chemical engineering professionals. Also to provide students with opportunities that are not available within the classroom and are related to the field of chemical and biochemical engineering. The Annual Technical fest of USCT, Chemchord, is the celebration of the spirit of chemical potential of the students. It provides the students an opportunity to build and enhance their perspective and broaden their horizon, exchange ideas, collaborate and learn and have fun all under the same roof and at same time. The student chapter of IIChE (Indian Institute of Chemical Engineers) has been opened since 2016 | https://en.wikipedia.org/wiki?curid=30690380 |
University School of Chemical Technology Students of USCT have participated in many notable national as well as international competitions such as Schemcon and those organised by AIChE(American Institute of Chemical Engineers). The school has a strong Alumni Association which enhances the fraternity experience of their own students and help them in professional activities in many ways. USCT Alumni meets once in a year to rejuvenate the association and share experiences. The Alumni are exhibiting their might and professional powers to their respective employee companies and thus advancing the national progress. Every year, the Alumni Meet of USCT is held to promote student-alumni interaction. Rohan Joshi(Batch 2021)is a popular stand up comedian, who also became Mr. Anugoonj 2018. The Alumni are currently working in many leading organizations like Haldor Topsoe, Fluor Daniel, Shell, IOCL, ONGC, EIL, Schlumberger, Reliance and the list continues. | https://en.wikipedia.org/wiki?curid=30690380 |
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