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Madeleine M. Joullié Then she moved to Philadelphia, where she was the only full-time female graduate student in chemistry at the University of Pennsylvania. There weren't even bathrooms for women in the chemistry building. She earned an M.S. from the University of Pennsylvania in 1950 and a Ph.D. in 1953. She worked w... | https://en.wikipedia.org/wiki?curid=42746040 |
Madeleine M. Joullié Joullié was active in the safety committee at UPenn, helping to identify and enforce safe work guidelines for the chemistry department. In 1970, Joullié and Mildred Cohn worked on the Committee on the Status of Women, which gathered data and documented the second-class status of women at Penn. The ... | https://en.wikipedia.org/wiki?curid=42746040 |
Madeleine M. Joullié The School of Arts and Sciences was so successful with their affirmative action program that I was then asked by the provost to chair the Council for Equal Opportunity to oversee the affirmative action programs of all the schools at Penn." Described by professor Helen Davies as "fearless and formid... | https://en.wikipedia.org/wiki?curid=42746040 |
Madeleine M. Joullié Her subsequent work has led to the total synthesis of several natural products, including muscarine, geiparvarin, ascofuranone, furanomycin, and dihydromauritine A. Working with Judah Folkman at Harvard Medical School and Paul B. Weisz at the University of Pennsylvania, Joullié helped to synthesize... | https://en.wikipedia.org/wiki?curid=42746040 |
Madeleine M. Joullié She has also developed probe molecules that can trace didemnins, allowing researchers to more effectively study their biological activities. Another area of research has been ninhydrin analogs. Joullié's lab has developed compounds with enhanced chromogenic and fluorogenic properties, useful in fin... | https://en.wikipedia.org/wiki?curid=42746040 |
Tetralone may refer to either of two chemical isomers: | https://en.wikipedia.org/wiki?curid=42753021 |
Multiscale tomography Multiscale Tomography (or multi-length scale tomography) is a form of tomography spanning large orders of magnitude in resolution, often utilizing many different forms of tomography together to do so. The forms of tomography combined in the process depend on what is being studied and the details n... | https://en.wikipedia.org/wiki?curid=42756265 |
Schmid's law (also Schmid factor, formula_1) describes the slip plane and the slip direction of a stressed material, which can resolve the most shear stress. Schmid's Law states that the critically resolved shear stress (τ) is equal to the stress applied to the material (σ) multiplied by the cosine of the angle with th... | https://en.wikipedia.org/wiki?curid=42763563 |
Trade Unions International of Chemical, Oil and Allied Workers The was a trade union international affiliated with the World Federation of Trade Unions. It was often known by its French initials, ICPS (Union Internationale des Syndicats des Industries, Chimiques, du Petroles et Similares). The Union was established at ... | https://en.wikipedia.org/wiki?curid=42766790 |
Trade Unions International of Chemical, Oil and Allied Workers The bureau, composed of the TUI president, vice-presidents, general secretary and secretaries met to ensure the fulfillment of the administrative committees decisions and a permanent secretariat oversaw day-to-day operations. Industrial Commissions were als... | https://en.wikipedia.org/wiki?curid=42766790 |
Amidicity The amidicity scale is a computational method for calculating the strength of an amide bond in an organic compound on a linear scale. It is analogous to aromaticity. It is based on the computed enthalpy of hydrogenation when compared to the reference compounds dimethylacetamide and azaadamantane-2-one. If an ... | https://en.wikipedia.org/wiki?curid=42777214 |
Prediction of crystal properties by numerical simulation The prediction of crystal properties by numerical simulation has become commonplace in the last 20 years as computers have grown more powerful and theoretical techniques more sophisticated. High accuracy prediction of elastic, electronic, transport and phase prop... | https://en.wikipedia.org/wiki?curid=42777908 |
Prediction of crystal properties by numerical simulation Thus, by beginning with a suitably parametrized guess and minimizing the energy with respect to each of those parameters, an extremely accurate prediction may be made. The question as to what one's initial guess should be is a topic of active research. In the lar... | https://en.wikipedia.org/wiki?curid=42777908 |
Prediction of crystal properties by numerical simulation Crystal structure calculations rely on periodic boundary conditions. That is, the assumption is that the cell you have chosen is in the midst of an infinite lattice of identical cells. By taking our 1 Na 1 Cl cell and copying it many times along each of the cryst... | https://en.wikipedia.org/wiki?curid=42777908 |
Prediction of crystal properties by numerical simulation The temperature of the system can be estimated by use of the Equipartition Theorem, with three degrees of freedom for each ion. Since ionic velocities are generally recorded at each step in the numerical simulation, the average kinetic energy of each ion is easy ... | https://en.wikipedia.org/wiki?curid=42777908 |
Prediction of crystal properties by numerical simulation Packages such as VASP have an option to calculate the electronic density of states per eV to facilitate the prediction of conduction bands and band gaps. The Green-Kubo relations can be used to calculate the thermal transport properties of a mineral. Since the ve... | https://en.wikipedia.org/wiki?curid=42777908 |
Le Bail method Le Bail analysis is a whole diffraction pattern profile fitting technique used to characterize the properties of crystalline materials, such as structure. It was invented by Armel Le Bail around 1967. The extracts intensities (I) from powder diffraction data. This is done in order to find intensities tha... | https://en.wikipedia.org/wiki?curid=42779491 |
Le Bail method Le Bail technique is relevant for diffraction studies that involve using a radiation source, which may be neutron or synchrotron, to collect a high resolution, high quality powder diffraction profile. Initially, peak positions are found in the data. Next, the pattern is indexed in order to determine the ... | https://en.wikipedia.org/wiki?curid=42779491 |
Le Bail method The summation is carried out over all contributing profile points for a particular 2-theta bin. The summation process is known as profile intensity partitioning, and it works over any number of peaks. Le Bail technique works especially well with overlapping intensities since in this method the intensity ... | https://en.wikipedia.org/wiki?curid=42779491 |
Le Bail method Both methods improve subsequent structural refinements Le Bail analysis is commonly a part of Rietveld analysis software, such as GSAS/EXPGUI. It is also used in ARITVE, BGMN, EXPO, EXTRACT, FullProf, GENEFP, Jana2006, Overlap, Powder Cell, Rietan, and TOPAS. | https://en.wikipedia.org/wiki?curid=42779491 |
Vitrimers are a class of plastics, which are derived from thermosetting polymers (thermosets) and are very similar to them. consist of molecular, covalent networks, which can change their topology by thermally activated bond-exchange reactions. At high temperatures they can flow like viscoelastic liquids, at low temper... | https://en.wikipedia.org/wiki?curid=42791912 |
Vitrimers Besides epoxy resins based on diglycidyl ether of bisphenol A, other polymer networks have been used to produce vitrimers, such as aromatic polyesters, polylactic acid (polylactide), polyhydroxyurethanes, epoxidized soybean oil with citric acid and polybutadiene. Thermoplastics are easy to process, but corrod... | https://en.wikipedia.org/wiki?curid=42791912 |
Vitrimers Therefore, they must be polymerized in the desired shape, which is time-consuming, restricts the shape and is responsible for their high price. Given this, if the chains can be held together reversible, strong covalent bonds, the resultant polymer would have the advantages of both thermoplastics and thermoset... | https://en.wikipedia.org/wiki?curid=42791912 |
Vitrimers If the "melt" of an (organic) amorphous polymer is cooled down, it solidifies at the glass-transition temperature T. On cooling, the hardness of the polymer increases in the neighborhood of T by several orders of magnitude. This hardening follows the Williams-Landel-Ferry equation, not the Arrhenius equation.... | https://en.wikipedia.org/wiki?curid=42791912 |
Vitrimers Moreover, because the exchange reactions follow Arrhenius' Law, the change of viscosity of vitrimers also follows an Arrhenius relationship with the increase of temperature, differing greatly from conventional organic polymers. The research group led by Ludwik Leibler demonstrated the operating principle of v... | https://en.wikipedia.org/wiki?curid=42791912 |
Vitrimers , about polyactide vitrimers, they demonstrated that the more ester groups present in the polymer, the faster the rates of relaxation will be, leading to better self-healing performance. Polyactide vitrimers which are synthesized by cross linking reactions of hydroxylterminated 4-arm star-shaped poly((±)-lact... | https://en.wikipedia.org/wiki?curid=42791912 |
Vitrimers Recent NASA-funded work on reversible adhesives for in-space assembly has used a high performance vitrimer system called aromatic thermosetting copolyester (ATSP) as the basis for coatings and composites reversibly bondable in the solid state – providing new possibilities for the assembly of large, complex st... | https://en.wikipedia.org/wiki?curid=42791912 |
Sodium cyanate (NaOCN) is a white crystalline solid that adopts a body centered rhombohedral crystal lattice structure (trigonal crystal system) at room temperature. can be prepared by the reaction between urea and sodium carbonate. Alternatively, it can be prepared by the oxidation of sodium cyanide. This can be done ... | https://en.wikipedia.org/wiki?curid=42793721 |
Sodium cyanate In most cases the intermediates produced with sodium cyanide are used for medicinal study; however, in the cases of sickle cell anemia and anti-carcinogenic research sodium cyanate itself was the compound of interest. | https://en.wikipedia.org/wiki?curid=42793721 |
Sulfonamide In chemistry, the sulfonamide functional group (also spelled sulphonamide) is -S(=O)-NH, a sulfonyl group connected to an amine group. Relatively speaking this group is unreactive. The amine center is no longer basic. The S-N bond is cleaved only with difficulty. Because of the rigidity of the functional gr... | https://en.wikipedia.org/wiki?curid=42797118 |
Sulfonamide The reaction of primary and secondary amines with benzenesulfonyl chloride is the basis of the Hinsberg reaction, a method for detecting primary and secondary amines. Sultams are cyclic sulfonamides. Bioactive sultams include the antiinflammatory ampiroxicam and the anticonvulsant sultiame. Sultams are prep... | https://en.wikipedia.org/wiki?curid=42797118 |
Sensor Coating Systems (SCS) is an instrumentation company that develops temperature-sensing technologies. It was formerly part of Southside Thermal Sciences. At the beginning of 2018, SCS started a project with NASA and other companies working in the aerospatial industry. This project called CAUTION has the aim to inc... | https://en.wikipedia.org/wiki?curid=42800060 |
Sensor Coating Systems The table below shows the differences between the Thermal History Coating and the Thermal History Paint: A thermal history coating (THC) is a robust coating containing various non-toxic chemical compounds whose crystal structures irreversibly change at high temperatures. This allows for temperatu... | https://en.wikipedia.org/wiki?curid=42800060 |
Ribosomally synthesized and post-translationally modified peptides (RiPPs), also known as ribosomal natural products, are a diverse class of natural products of ribosomal origin. Consisting of more than 20 sub-classes, RiPPs are produced by a variety of organisms, including prokaryotes, eukaryotes, and archaea, and the... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides In 2013, a set of uniform nomenclature guidelines were agreed upon and published by a large group of researchers in the field. Prior to this report, RiPPs were referred to by a variety of designations, including "post-ribosomal peptides", "ribosomal nat... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides LFF571, a derivative of the thiopeptide GE2270-A, completed phase II clinical trials for the treatment of "Clostridium difficile" infections, with comparable safety and efficacy to vancomycin. Also recently in clinical trials was the NVB302 (a derivativ... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides Bottromycins contain a C-terminal decarboxylated thiazole in addition to a macrocyclic amidine. There are currently six known bottromycin compounds, which differ in the extent of side chain methylation, an additional characteristic of the bottromycin cl... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides "A" is a serine protease involved in cleavage of the leader peptide and subsequent macrocyclization of the peptide natural product, in combination with an additional serine protease homologue, the encoded by gene "G". Members of the cyanobactin family m... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides Because of this threaded-loop topology, these peptides resemble lassos, giving rise to their name. Additionally, lasso peptides are formally rotaxanes. The N-terminal "ring" can be from 7 to 9 amino acids long and is formed by an isopeptide bond between... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides Azole and azoline formation also modifies the residue in the -1 position, or directly "C"-terminal to the Cys, Ser, or Thr. A dehydrogenase in the LAP gene cluster is required for oxidation of azolines to azoles. Plantazolicin is a LAP with extensive cy... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides Microcins have bioactivity against Gram-negative bacteria but usually display narrow-spectrum activity due to hijacking of specific receptors involved in the transport of essential nutrients. Most of the characterized thiopeptides have been isolated fro... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides In pathogens, exported AIPs bind to extracellular receptors that trigger the production of virulence factors. In "Staphylococcus aureus", AIPs are biosynthesized from a precursor peptide composed of a C-terminal leader region, the core region, and negat... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides Venom peptides from cone snails are generally smaller than those found in other animal venoms (10-30 amino acids vs. 30-90 amino acids) and have more disulfide crosslinks. A single species may have 50-200 conopeptides encoded in its genome, recognizable... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides In addition, the linaridin moiety is formed from modification of two Cys residues, whereas lanthipeptide aminovinyl cysteines are formed from Cys and dehydroalanine (Dha). The first linaridin to be characterized was cypemycin. "Microviridins" are cyclic... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides In the case of subtilosin A, isolated from Bacillus subtilis 168, the Cα crosslinks between Cys4 and Phe31, Cys7 and Thr28, and Cys13 and Phe22 are not the only posttranslational modifications; the C- and N-termini form an amide bond, resulting in a cir... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides Examples of modifications include dehydration (i.e. lanthipeptides, thiopeptides), cyclodehydration (i.e. thiopeptides), prenylation (i.e. cyanobactins), and cyclization (i.e. lasso peptides), among others. The resulting modified precursor peptide (cont... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides Class I lanthipeptides have dedicated lanthipeptide dehydratases, called LanB enzymes, though more specific designations are used for particular lanthipeptides (e.g. NisB is the nisin dehydratase). A separate cyclase, LanC, is responsible for the second... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides This occurs by direct activation of the amide backbone carbonyl with ATP, resulting in stoichiometric ATP consumption. The C and D proteins are occasionally present as a single, fused protein, as is the case for trunkamide biosynthesis. The B protein is... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides Many cyanobactins also undergo heterocyclization by a heterocyclase (referred to as the D protein), installing oxazoline or thiazoline moieties from Ser/Thr/Cys residues prior to the action of the A and G proteases. The heterocyclase is an ATP-dependent... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides These include lanthipeptide-like dehydratases, designated the B and C proteins, which install dehydroalanine and dehydrobutyrine moieties by dehydrating Ser/Thr precursor residues. Azole and azoline synthesis is effected by the E protein, the dehydrogen... | https://en.wikipedia.org/wiki?curid=42804273 |
Ribosomally synthesized and post-translationally modified peptides The B protein is an adenosine triphosphate-dependent cysteine protease that cleaves the leader region from the precursor peptide. The C protein displays homology to asparagine synthetase and is thought to activate the carboxylic acid side chain of a glu... | https://en.wikipedia.org/wiki?curid=42804273 |
Hibakujumoku (; also called survivor tree or A-bombed tree in English) is a Japanese term for a tree that survived the atomic bombings of Hiroshima and Nagasaki in 1945. The term is from and . The heat emitted by the explosion in Hiroshima within the first three seconds at a distance of three kilometres from the hypoce... | https://en.wikipedia.org/wiki?curid=42812909 |
Sodium germanate (NaGeO) is a colorless solid chemical compound. can be prepared by the fusion of germanium oxide with sodium oxide at high temperatures. NaGeO contains polymeric GeO anions made up of vertex sharing {GeO} tetrahedra. is primarily used for the synthesis of other germanium compounds. | https://en.wikipedia.org/wiki?curid=42816580 |
Rhazinilam is an alkaloid first isolated in 1965 by Linde from the "Melodinus australis" plant. It was later isolated from the shrub "Rhazya stricta" as well as from other organisms. has activity similar to that of colchicine, taxol and vinblastine, acting as a spindle poison. was first synthesized in 1973 by Smith and... | https://en.wikipedia.org/wiki?curid=42818038 |
Rhamnosidase may refer to: | https://en.wikipedia.org/wiki?curid=42821627 |
Iris Long Iris Lillian Doerr Long (born December 8, 1934) is an American chemist and activist in the AIDS Coalition to Unleash Power (ACT UP) effort to spread information about the possible Antiviral drugs that could be used to combat HIV/AIDS. Iris Lillian Doerr Long was born December 8, 1934 in New York City, New Yor... | https://en.wikipedia.org/wiki?curid=42827918 |
Iris Long Many of the drugs being taken were anti-cancer drugs. However, around March 1987 she attended a meeting of ACT-UP and was struck by the group's approach. She brought the group information on a clinical trial carried out on HIV positive patients by the National Institute of Allergy and Infectious Disease (NIAI... | https://en.wikipedia.org/wiki?curid=42827918 |
Selig Hecht (1892 – 1947) was an American physiologist who studied photochemistry in photoreceptor cells. Hecht was born in Austria, and immigrated to the USA at an early age. His studies and talents led to Columbia University making him professor of biophysics in 1928. In June 1917 Hecht received his Ph.D. and married... | https://en.wikipedia.org/wiki?curid=42828447 |
Selig Hecht Jelinek asserts that the book is "profoundly provocative in its political and sociological implications." After Hecht died, a second edition was issued in 1959 by Eugene Rabinowitch. | https://en.wikipedia.org/wiki?curid=42828447 |
GRE Chemistry Test The GRE subject test in chemistry is a standardized test in the United States created by the Educational Testing Service, and is designed to assess a candidate's potential for graduate or post-graduate study in the field of chemistry. It contains questions from many fields of chemistry. 15% of the qu... | https://en.wikipedia.org/wiki?curid=42834178 |
Jean-Claude Bradley was a chemist who actively promoted Open Science in chemistry, including at the White House, for which he was awarded the Blue Obelisk award in 2007. He coined the term "Open Notebook science". He died in May 2014. A memorial symposium was held July 14, 2014 at Cambridge University, UK. One outcome ... | https://en.wikipedia.org/wiki?curid=42840327 |
SYSACCO is a Syrian-Saudi Chemical Company with headquarter in Aleppo, Syria. Their chemical plant with an area of 142,000 m is located east of Aleppo. is Syria’s only chlorine manufacturing plant. They mostly produce products for water sterilization to the local market: | https://en.wikipedia.org/wiki?curid=42840382 |
Methoxypsoralen may refer to: | https://en.wikipedia.org/wiki?curid=42841152 |
De materia medica (Latin name for the Greek work Περὶ ὕλης ἰατρικῆς, "Peri hulēs iatrikēs", both meaning "On Medical Material") is a pharmacopoeia of medicinal plants and the medicines that can be obtained from them. The five-volume work was written between 50 and 70 CE by Pedanius Dioscorides, a Greek physician in the... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica Several manuscripts and early printed versions of "De materia medica" survive, including the illustrated Vienna Dioscurides manuscript written in the original Greek in sixth-century Constantinople; it was used there by the Byzantines as a hospital text for just over a thousand years. Sir Arthur Hill s... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica While being reproduced in manuscript form through the centuries, the text was often supplemented with commentary and minor additions from Arabic and Indian sources. Several illustrated manuscripts of "De materia medica" survive. The most famous is the lavishly illustrated Vienna Dioscurides (the "Juli... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica The work presents about 600 medicinal plants in all, along with some animals and mineral substances, and around 1000 medicines made from these sources. Botanists have not always found Dioscorides' plants easy to identify from his short descriptions, partly because he had naturally described plants and... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica Its effects are summarized, accompanied by a caution: Dioscorides then describes how to tell a good from a counterfeit preparation. He mentions the recommendations of other physicians, Diagoras (according to Eristratus), Andreas, and Mnesidemus, only to dismiss them as false and not borne out by exper... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica They include what are probably cardamom, nard, valerian, cassia or senna, cinnamon, balm of Gilead, hops, mastic, turpentine, pine resin, bitumen, heather, quince, apple, peach, apricot, lemon, pear, medlar, plum and many others. Volume II covers an assortment of topics: animals including sea creature... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica It was translated first into Syriac and then into Arabic in 9th century Baghdad. Writing in "The Great Naturalists", the historian of science David Sutton describes "De materia medica" as "one of the most enduring works of natural history ever written" and that "it formed the basis for Western knowled... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica The historian of medicine Vivian Nutton, in "Ancient Medicine", writes that Dioscorides's "five books in Greek On Materia medica attained canonical status in Late Antiquity." The historian of science Brian Ogilvie calls Dioscorides "the greatest ancient herbalist", and "De materia medica" "the "summa"... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica Many other substances that Dioscorides describes remain in modern pharmacopoeias as "minor drugs, diluents, flavouring agents, and emollients ... [such as] ammoniacum, anise, cardamoms, catechu, cinnamon, colocynth, coriander, crocus, dill, fennel, galbanum, gentian, hemlock, hyoscyamus, lavender, lin... | https://en.wikipedia.org/wiki?curid=42841555 |
De materia medica In the view of the historian Paula De Vos, "De materia medica" formed the core of the European pharmacopoeia until the end of the 19th century, suggesting that "the timelessness of Dioscorides' work resulted from an empirical tradition based on trial and error; that it worked for generation after gene... | https://en.wikipedia.org/wiki?curid=42841555 |
Transcription-mediated amplification (TMA) is an isothermal (does not change the nucleic acid temperature), single-tube nucleic acid amplification system utilizing two enzymes, RNA polymerase and reverse transcriptase. "Amplification" means creating many more copies of a strand of nucleic acid than was present at first... | https://en.wikipedia.org/wiki?curid=42848638 |
W. Clark Still (born 1946) is an American organic chemist. As a distinguished professor at Columbia University, Clark Still made significant contributions to the field of organic chemistry, particularly in the areas of natural product synthesis, reaction development, conformational analysis, macrocyclic stereocontrol, ... | https://en.wikipedia.org/wiki?curid=42848711 |
W. Clark Still <br> These transformations set the stage for the introduction of both epoxide groups, which were formed with high levels of diastereoselectivity based on the principles of macrocyclic stereocontrol. The first epoxide was introduced via nucleophilic epoxidation of the enone using potassium hydride and ter... | https://en.wikipedia.org/wiki?curid=42848711 |
W. Clark Still Subsequent addition of the aldehyde component initiated a diastereoselective aldol reaction, forming the desired beta-hydroxyketone in 75% yield as a 3:1 mixture of diastereomers. Notably, this instance of acyclic stereocontrol is consistent with the Cram-Felkin-Anh model for the addition of nucleophiles... | https://en.wikipedia.org/wiki?curid=42848711 |
W. Clark Still In 1978, Still dramatically increased the scope of the 2,3-Wittig rearrangement by introducing an organotin-substituted ether as a precursor to the alkoxy-substituted carbanion. In this procedure, transmetalation of the organotin group can be achieved chemoselectively at low temperature using n-butyllith... | https://en.wikipedia.org/wiki?curid=42848711 |
W. Clark Still In the standard HWE reaction, the phosphonate ester contains alkoxy substituents (typically methoxy or ethoxy), producing an "E"-alkene as the major product. In 1983, Still and Gennari reported that simply substituting the more electron-withdrawing 2,2,2-trifluoroethoxy groups on the phosphonate componen... | https://en.wikipedia.org/wiki?curid=42848711 |
W. Clark Still However, elution of the solvent by gravity alone was often a tedious process, requiring several hours and leading to poor separations due to band broadening via diffusion. Still's innovation was to apply pressure to the top of the column to increase the speed of solvent elution. Not only did this drastic... | https://en.wikipedia.org/wiki?curid=42848711 |
W. Clark Still Conformational analysis was integral to Still's study of macrocyclic stereocontrol, and there was a general need for a fast and reliable computational method for predicting an organic molecule's lowest energy conformation. In order to address the problem, Still and coworkers reported a simple Monte Carlo... | https://en.wikipedia.org/wiki?curid=42848711 |
W. Clark Still Still disclosed a full description of MacroModel in the Journal of Computation Chemistry in 1990, and the rights to this software were later acquired by Schrodinger, Inc. in 1998. | https://en.wikipedia.org/wiki?curid=42848711 |
Octanone may refer to any of three isomeric chemical compounds: | https://en.wikipedia.org/wiki?curid=42861759 |
Dioxygen difluoride is a compound of fluorine and oxygen with the molecular formula . It can exist as an orange-colored solid which melts into a red liquid at . It is an extremely strong oxidant and decomposes into oxygen and fluorine even at at a rate of 4% per day: its lifetime at room temperature is thus extremely s... | https://en.wikipedia.org/wiki?curid=2171432 |
Dioxygen difluoride The bonding within dioxygen difluoride has been the subject of considerable speculation, particularly because of the very short O−O distance and the long O−F distances. The O−O bond length is within 2 pm of the 120.7 pm distance for the O=O double bond in the dioxygen molecule, . Several bonding sys... | https://en.wikipedia.org/wiki?curid=2171432 |
Dioxygen difluoride Several series of experiments with the compound resulted in a series of fires and explosions. Some of the compounds that produced violent reactions with include ethyl alcohol, methane, ammonia, and even water ice. With and , it gives the corresponding dioxygenyl salts: The compound currently has no ... | https://en.wikipedia.org/wiki?curid=2171432 |
Fixative (perfumery) A fixative is used to equalize the vapor pressures, and thus the volatilities, of the raw materials in a perfume oil, as well as to increase the tenacity. Natural fixatives are resinoids (benzoin, labdanum, myrrh, olibanum, storax, tolu balsam) and animal products (ambergris, castoreum, musk, and c... | https://en.wikipedia.org/wiki?curid=2171777 |
Lithium perchlorate is the inorganic compound with the formula LiClO. This white or colourless crystalline salt is noteworthy for its high solubility in many solvents. It exists both in anhydrous form and as a trihydrate. is used as a source of oxygen in some chemical oxygen generators. It decomposes at about 400 °C, y... | https://en.wikipedia.org/wiki?curid=2172095 |
Lithium perchlorate However, these beneficial properties are often overshadowed by the electrolyte's strong oxidizing properties, making the electrolyte reactive toward its solvent at high temperatures and/or high current loads. Due to these hazards the battery is often considered unfit for industrial applications. Con... | https://en.wikipedia.org/wiki?curid=2172095 |
Silver perchlorate is the chemical compound with the formula AgClO. This white solid forms a monohydrate and is mildly deliquescent. It is a useful source of the Ag ion, although the presence of perchlorate presents risks. It is used as a catalyst in organic chemistry. is created by heating a mixture of perchloric acid... | https://en.wikipedia.org/wiki?curid=2172106 |
Sodium periodate is an inorganic salt, composed of a sodium cation and the periodate anion. It may also be regarded as the sodium salt of periodic acid. Like many periodates it can exist in two different forms: sodium "meta"periodate, which has the formula NaIO, and sodium "ortho"periodate, normally this means sodium h... | https://en.wikipedia.org/wiki?curid=2172265 |
Sodium periodate Powder diffraction indicates that NaIO crystallises in the monoclinic system (space group C2/m). can be used in solution to open saccharide rings between vicinal diols leaving two aldehyde groups. This process is often used in labeling saccharides with fluorescent molecules or other tags such as biotin... | https://en.wikipedia.org/wiki?curid=2172265 |
Potassium periodate is an inorganic salt with the molecular formula KIO. It is composed of a potassium cation and a periodate anion and may also be regarded as the potassium salt of periodic acid. Note that the pronunciation is per-iodate, not period-ate. Unlike other common periodates, such as sodium periodate and per... | https://en.wikipedia.org/wiki?curid=2172275 |
Scattering channel In scattering theory, a scattering channel is a quantum state of the colliding system before or after the collision (formula_1). The Hilbert space spanned by the states before collision (in states) is equal to the space spanned by the states after collision (out states) which are both Fock spaces if ... | https://en.wikipedia.org/wiki?curid=2172915 |
Nick translation (or head translation), developed in 1977 by Peter Rigby and Paul Berg, is a tagging technique in molecular biology in which DNA Polymerase I is used to replace some of the nucleotides of a DNA sequence with their labeled analogues, creating a tagged DNA sequence which can be used as a probe in fluoresc... | https://en.wikipedia.org/wiki?curid=2173109 |
Nick translation could cause double-stranded DNA breaks, if DNA polymerase I encounters another nick on the opposite strand, resulting in two shorter fragments. This does not influence the performance of the labelled probe in in-situ hybridization. | https://en.wikipedia.org/wiki?curid=2173109 |
Avoided crossing In quantum physics and quantum chemistry, an avoided crossing (sometimes called intended crossing, "non-crossing" or anticrossing) is the phenomenon where two eigenvalues of an Hermitian matrix representing a quantum observable and depending on "N" continuous real parameters cannot become equal in valu... | https://en.wikipedia.org/wiki?curid=2174011 |
Avoided crossing These two eigenvectors designate the two states of the system. If the system is prepared in either of the states it would remain in that state. If formula_6 happens to be equal to formula_7 there will be a twofold degeneracy in the Hamiltonian. In that case any superposition of the degenerate eigenstat... | https://en.wikipedia.org/wiki?curid=2174011 |
Avoided crossing The immediate impact of avoided level crossing in a degenerate two state system is the emergence of a lowered energy eigenstate. The effective lowering of energy always correspond to increasing stability.(see: Energy minimization) Bond resonance in organic molecules exemplifies the occurrence of such a... | https://en.wikipedia.org/wiki?curid=2174011 |
Avoided crossing So the corresponding stable system will naturally mix up the former unperturbed eigenstates to minimize its energy. In the example of Benzene the experimental evidences of probable bond structures give rise to two different eigenstates, formula_20 and formula_21. The symmetry of these two structures ma... | https://en.wikipedia.org/wiki?curid=2174011 |
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