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One of the theories on the specific formation mechanism for bainite is that it occurs by a shear transformation, as in martensite. The crystal structure change is achieved by a deformation rather than by diffusion. The shape change associated with bainite is an invariant—plane strain with a large shear component. Thi...
8
Metallurgy
In molecular biology, gel extraction or gel isolation is a technique used to isolate a desired fragment of intact DNA from an agarose gel following agarose gel electrophoresis. After extraction, fragments of interest can be mixed, precipitated, and enzymatically ligated together in several simple steps. This process, ...
1
Biochemistry
The stereochemical term diastereotopic refers to the relationship between two groups in a molecule which, if replaced, would generate compounds that are diastereomers. Diastereotopic groups are often, but not always, identical groups attached to the same atom in a molecule containing at least one chiral center. For exa...
4
Stereochemistry
Two-dimensional diffraction images of a fine synchrotron beam interacting with the specimen are recorded in time frames, such that reflections stemming from individual crystallites of the polycrystalline material can be distinguished. Data treatment is undertaken in a way that diffraction rings are straightened and pre...
7
Physical Chemistry
Total ionic strength adjustment buffer (TISAB) is a buffer solution which increases the ionic strength of a solution to a relatively high level. This is important for potentiometric measurements, including ion selective electrodes, because they measure the activity of the analyte rather than its concentration. TISAB es...
3
Analytical Chemistry
Source: *1997 Ahmed Zewail *1998 Robin M. Hochstrasser *1999 Richard N. Zare *2000 Ad Bax *2001 William A. Klemperer *2002 Takeshi Oka *2003 Marilyn E. Jacox *2004 James K.G. Watson *2005 Eizi Hirota *2006 Donald H. Levy *2007 Michael D. Fayer *2008 Jack H. Freed *2009 Paul F. Barbara *2010 George W. Flynn *2011 Veroni...
7
Physical Chemistry
The commercial manufacture of wood pulp grade chemical cellulose using the kraft chemical pulping processes releases resin acids. The Kraft process is conducted under strongly basic conditions of sodium hydroxide, sodium sulfide and sodium hydrosulfide, which neutralizes these resin acids, converting them to their res...
1
Biochemistry
The structure of DNA shows a variety of forms, both double-stranded and single-stranded. The mechanical properties of DNA, which are directly related to its structure, are a significant problem for cells. Every process which binds or reads DNA is able to use or modify the mechanical properties of DNA for purposes of re...
4
Stereochemistry
There is significant overlap in function with regards to some of these proteins. In particular, the Rho-related genes are important in nuclear trafficking (i.e.: mitosis) as well as with mobility along the cytoskeleton in general. These genes of particular interest in cancer research. *ARHGAP35 *ARHGAP5 *ARHGDIA *...
1
Biochemistry
Elevated blood ketone levels are most often caused by accelerated ketone production but may also be caused by consumption of exogenous ketones or precursors. When glycogen and blood glucose reserves are low, a metabolic shift occurs in order to save glucose for the brain which is unable to use fatty acids for energy. T...
1
Biochemistry
The phosphate/oxygen ratio, or P/O ratio, refers to the amount of ATP produced from the movement of two electrons through a defined electron transport chain, terminated by reduction of an oxygen atom. The P/O ratio is dependent on the number of hydrogen ions transported outward across an electrochemical gradient, and t...
1
Biochemistry
There are many biologically active chemicals which elicit an effect on the nervous system. Neurotransmitters and similarly functioning biochemical messengers elicit effects on postsynaptic neurons at neuronal synapses. Excitatory Amino Acids include Glutamate, whereas inhibitory Amino Acids include GABA and Glycine. Ad...
1
Biochemistry
The formal naming of haloalkanes should follow IUPAC nomenclature, which put the halogen as a prefix to the alkane. For example, ethane with bromine becomes bromoethane, methane with four chlorine groups becomes tetrachloromethane. However, many of these compounds have already an established trivial name, which is endo...
0
Organic Chemistry
OCP was first described in 1981 by Holt and Krogmann who isolated it from the unicellular cyanobacterium Arthrospira maxima, although its function would remain obscure until 2006. The crystal structure of the OCP was reported in 2003. At the same time the protein was shown to be an effective quencher of singlet oxygen...
5
Photochemistry
In evolutionary developmental biology, homeosis is the transformation of one organ into another, arising from mutation in or misexpression of certain developmentally critical genes, specifically homeotic genes. In animals, these developmental genes specifically control the development of organs on their anteroposterior...
1
Biochemistry
Iron-sulfur proteins are involved in various biological electron transport processes, such as photosynthesis and cellular respiration, which require rapid electron transfer to sustain the energy or biochemical needs of the organism. To serve their various biological roles, iron-sulfur proteins effect rapid electron tra...
7
Physical Chemistry
Methyl fluoroacetate is a methyl ester of fluoroacetic acid. MFA is a liquid, which is odorless or can have a faint, fruity smell. The boiling point of MFA is 104.5 °C and the melting point is −35.0 °C. It is soluble in water (117 g/L at 25 °C) and slightly soluble in petroleum ether. MFA is resistant to the displaceme...
1
Biochemistry
GenePattern is available: # As a free public web application, hosted on Amazon Web Services. Users can create accounts, perform analyses, and create pipelines on the server. # As open-source software that can be downloaded and installed locally. # Public web servers hosted by other organizations.
1
Biochemistry
Ethane-1,2-dithiol is made commercially by the reaction of 1,2-dichloroethane with aqueous sodium bisulfide. In the laboratory, it can also be prepared by the action of 1,2-dibromoethane on thiourea followed by hydrolysis.
0
Organic Chemistry
The patio process is a process for extracting silver from ore. Smelting, or refining, is most often necessary because silver is only infrequently found as a native element like some metals nobler than the redox couple 2 + 2 ⇌ (gold, mercury, ...). Instead, it is made up of a larger ore body. Thus, smelting, or refini...
8
Metallurgy
Until recently, there were only two known pathways to process Okazaki fragments. However, current investigations have concluded that a new pathway for Okazaki fragmentation and DNA replication exists. This alternate pathway involves the enzymes Pol δ with Pif1 which perform the same flap removal process as Pol δ and FE...
1
Biochemistry
The Sonogashira reaction is typically run under mild conditions. The cross-coupling is carried out at room temperature with a base, typically an amine, such as diethylamine, that also acts as the solvent. The reaction medium must be basic to neutralize the hydrogen halide produced as the byproduct of this coupling reac...
0
Organic Chemistry
Because water molecules absorb microwaves and other radio wave frequencies, water in the atmosphere attenuates radar signals. In addition, atmospheric water will reflect and refract signals to an extent that depends on whether it is vapor, liquid or solid. Generally, radar signals lose strength progressively the farthe...
2
Environmental Chemistry
Adsorbable organic halides (AOX) is a measure of the organic halogen load at a sampling site such as soil from a land fill, water, or sewage waste. The procedure measures chlorine, bromine, and iodine as equivalent halogens, but does not measure fluorine levels in the sample.
2
Environmental Chemistry
Daily intakes of fluoride can vary significantly according to the various sources of exposure. Values ranging from 0.46 to 3.6–5.4 mg/day have been reported in several studies (IPCS, 1984). In areas where water is fluoridated this can be expected to be a significant source of fluoride, however fluoride is also naturall...
1
Biochemistry
Two adjacent structural units in a polymer molecule constitute a diad. Diads overlap: each structural unit is considered part of two diads, one diad with each neighbor. If a diad consists of two identically oriented units, the diad is called a meso diad (abbreviated m) as in a meso compound. If a diad consists of unit...
4
Stereochemistry
Cytoplasmic abundant heat soluble (CAHS) proteins are highly expressed in response to desiccation. There are two hypotheses for their function in tardigrades. The vitrification hypothesis is the idea that, when a tardigrade becomes desiccated, the viscosity within its cells increases to the point that denaturation and ...
1
Biochemistry
In chemistry and crystallography, crystal structures that have the same set of interatomic distances are called homometric structures. Homometric structures need not be congruent (that is, related by a rigid motion or reflection). Homometric crystal structures produce identical diffraction patterns; therefore, they can...
4
Stereochemistry
In mathematics, a symmetry operation is a geometric transformation of an object that leaves the object looking the same after it has been carried out. For example, a turn rotation of a regular triangle about its center, a reflection of a square across its diagonal, a translation of the Euclidean plane, or a point refl...
7
Physical Chemistry
Once the C-H bond of methane is activated by bonding to a transition metal complex, the net functionalization of the alkyl metal complex into another hydrocarbon containing a functional group is actually much harder to achieve. In general, alkanes of various lengths have typically been functionalized by a number of mor...
0
Organic Chemistry
*Thermal wheel, or rotary heat exchanger (including enthalpy wheel and desiccant wheel) *Recuperator, or cross plate heat exchanger *Heat pipe
7
Physical Chemistry
The mineralization of copper is restricted to a few areas in western, central and southern Africa, and some have the richest deposits of copper in the world. In the west, copper has only been found in the arid regions of the Sahel and southern Sahara. The main sources of copper are: # Akjoujt in Mauritania # Nioro du S...
8
Metallurgy
For the case of counterpropagating waves with orthogonal circular polarizations the resulting polarization is linear everywhere, but rotates about at an angle . As a result, there is no Sisyphus effect. The rotating polarization instead leads to motion-induced population imbalances in the Zeeman levels that cause imba...
7
Physical Chemistry
Biochemists are scientists who are trained in biochemistry. They study chemical processes and chemical transformations in living organisms. Biochemists study DNA, proteins and cell parts. The word "biochemist" is a portmanteau of "biological chemist." Biochemists also research how certain chemical reactions happen in c...
1
Biochemistry
Cytochrome b559 is an important component of Photosystem II (PSII) is a multisubunit protein-pigment complex containing polypeptides both intrinsic and extrinsic to the photosynthetic membrane. Within the core of the complex, the chlorophyll and beta-carotene pigments are mainly bound to the antenna proteins CP43 (PsbC...
5
Photochemistry
Clinical trials of vitamin D supplementation for depressive symptoms have generally been of low quality and show no overall effect, although subgroup analysis showed supplementation for participants with clinically significant depressive symptoms or depressive disorder had a moderate effect.
1
Biochemistry
The first researcher to suggest the existence of a molecular knot in a protein was Jane Richardson in 1977, who reported that carbonic anhydrase B (CAB) exhibited apparent knotting during her survey of various proteins' topological behavior. However, the researcher generally attributed with the discovery of the first k...
6
Supramolecular Chemistry
Pasteur observed that fermentation does not require oxygen, but needs yeast, which is alive. Fermentation is a biological process, not a reduction and oxygen chemical process. He used two slender bottles. One of the bottles had a curved neck; this is called a swan neck. Pasteur poured liquid broth into the two bottles,...
1
Biochemistry
Below are useful results from the Maxwell–Boltzmann distribution for an ideal gas, and the implications of the Entropy quantity. The distribution is valid for atoms or molecules constituting ideal gases. Corollaries of the non-relativistic Maxwell–Boltzmann distribution are below.
7
Physical Chemistry
The 2006 Nobel Prize in Chemistry was awarded to Roger D. Kornberg for creating detailed molecular images of RNA polymerase during various stages of the transcription process. In most prokaryotes, a single RNA polymerase species transcribes all types of RNA. RNA polymerase "core" from E. coli consists of five subunits:...
1
Biochemistry
In Alabama, industrialization was generating a ravenous appetite for the states coal and iron ore. Production was booming, and unions were attempting to organize unincarcerated miners. Convicts provided an ideal captive work force: cheap, usually docile, unable to organize and available when unincarcerated laborers wen...
8
Metallurgy
The term excimer (excited state dimer) is, strictly speaking, limited to cases in which a true dimer is formed; that is, both components of the dimer are the same molecule or atom. The term exciplex refers to the heterodimeric case; however, common usage expands excimer to cover this situation.
5
Photochemistry
The term "paucimannose" (occasionally spelled as "pauci-mannose") was coined in the early 1990s glycobiology literature Paucimannose utilises the prefix "pauci" meaning few or small in Latin and the suffix "mannose" indicating glycans involving mannose-terminating glycans. The phrases protein paucimannosylation and pau...
1
Biochemistry
This metabolic pathway leading to the alternative oxidase diverges from the cytochrome-linked electron transport chain at the ubiquinone pool. Alternative pathway respiration only produces proton translocation at Complex 1 (NADH dehydrogenase) and so has a lower ATP yield than the full pathway. The expression of the al...
1
Biochemistry
Unsaturated compounds, especially alkenes and alkynes, add halogens: In oxychlorination, the combination of hydrogen chloride and oxygen serves as the equivalent of chlorine, as illustrated by this route to 1,2-dichloroethane: The addition of halogens to alkenes proceeds via intermediate halonium ions. In special cases...
0
Organic Chemistry
Lithium–sulfur system arranged in a network of nanoparticles eliminates the requirement that charge moves in and out of particles that are in direct contact with a conducting plate. Instead, the nanoparticle network allows electricity to flow throughout the liquid. This allows more energy to be extracted. In a Semi-sol...
7
Physical Chemistry
Spathulenol is a tricyclic sesquiterpene alcohol which has a basic skeleton similar to the azulenes. It occurs in oregano among other plants.
1
Biochemistry
Also well studied is the sea pansy, Renilla reniformis. In this organism, the luciferase (Renilla-luciferin 2-monooxygenase) is closely associated with a luciferin-binding protein as well as a green fluorescent protein (GFP). Calcium triggers release of the luciferin (coelenterazine) from the luciferin binding protein....
1
Biochemistry
The Sanford–Wang parameterisation is an empirical formula used to model the production of pions in nuclear interaction of the form p+A → +X where a beam of high-energy protons hit a material. Its formula for the double-differential cross section with respect to momentum (p) and solid angle () is as follows. Where p and...
7
Physical Chemistry
* Димитров П. 1988. [https://www.researchgate.net/publication/312155281_Dalec_ot_bregove_i_farvateri_Far_from_the_coasts_and_waterways Далеч от брегове и фарватери]. Варна. Изд. „Галактика“. Библиотека „Нептун“, 161 с., doi:[https://doi.org/10.13140/RG.2.2.19449.36965/1 10.13140/RG.2.2.19449.36965/1] * Димитров П., Д. ...
9
Geochemistry
Non-B DNA can be classified into several types, including A-DNA, Z-DNA, H-DNA, G-quadruplexes, and Triplexes (Triple-stranded DNA). A-DNA is a right-handed double helix structure for RNA-DNA duplexes and RNA-RNA duplexes that is less common than the more well-known B-DNA structure. A-DNA is a form of DNA that occurs w...
1
Biochemistry
Some researchers prefer to define the term “photoinhibition” so that it contains all reactions that lower the quantum yield of photosynthesis when a plant is exposed to light. In this case, the term "dynamic photoinhibition" comprises phenomena that reversibly down-regulate photosynthesis in the light and the term "pho...
5
Photochemistry
Heparin cofactor II (HCII), a protein encoded by the SERPIND1 gene, is a coagulation factor that inhibits IIa, and is a cofactor for heparin and dermatan sulfate ("minor antithrombin"). The product encoded by this gene is a serine protease inhibitor which rapidly inhibits thrombin in the presence of dermatan sulfate or...
1
Biochemistry
BSi preservation is measured by: * Sedimentation rates, mainly sediment traps (Honjo); * Benthic remineralization rates ("recycling"), benthic flux chamber (Berelson); * BSi concentration in sediments, chemical leaching in alkaline solution, site specific, need to differentiate lithogenic vs. biogenic Si, X-ray diffrac...
1
Biochemistry
;Wins * North American Bridge Championships (12) ** Master Mixed Teams (1) 1990 ** Open Swiss Teams (1) 1991 ** North American Swiss Teams (1) 1990 ** Grand National Open Teams (1) 1981 ** Men's Board-a-Match Teams (2) 1984, 1987 ** Reisinger Board-a-Match Teams (1) 1985 ** Spingold Knockout Teams (2) 1976, 1984 ** Van...
0
Organic Chemistry
A deuterated drug is a small molecule medicinal product in which one or more of the hydrogen atoms contained in the drug molecule have been replaced by deuterium. Because of the kinetic isotope effect, deuterium-containing drugs may have significantly lower rates of metabolism, and hence a longer half-life. In 2017, de...
9
Geochemistry
Phase inversion is a common method to form filtration membranes, which are typically formed using artificial polymers. The method of phase inversion is highly dependent on the type of polymer used and the solvent used to dissolve the polymer. Phase inversion can be carried out through one of four typical methods: *Redu...
7
Physical Chemistry
# Wash pipe ends to create clean surfaces for joining # Square pipe ends to facilitate optimal fit-up # Clean area where coupler will be placed with isopropyl alcohol # Mark the pipes slightly beyond half the length of the coupler, to indicate where scraping will take place in later steps # Mark the area to be scraped...
7
Physical Chemistry
Most cell types take up iron primarily through receptor-mediated endocytosis via transferrin receptor 1 (TFR1), transferrin receptor 2 (TFR2) and GAPDH. TFR1 has a 30-fold higher affinity for transferrin-bound iron than TFR2 and thus is the main player in this process. The higher order multifunctional glycolytic enzyme...
1
Biochemistry
Hellmut Fischmeister was elected as a foreign member of the Royal Swedish Academy of Engineering Sciences in 1975. In 1981, he was elected as a corresponding member of the Austrian Academy of Sciences and was a member of the Academia Europaea since 1989. In 1995, he became a full member of the mathematical-natural scie...
8
Metallurgy
The TFQI can be calculated with from quantiles of FT4 and TSH concentration (as determined based on cumulative distribution functions). Per definition the TFQI has a mean of 0 and a standard deviation of 0.37 in a reference population. This explains the reference range of –0.74 to + 0.74.
1
Biochemistry
In hydrothermal liquefaction processes, long carbon chain molecules in biomass are thermally cracked and oxygen is removed in the form of HO (dehydration) and CO (decarboxylation). These reactions result in the production of high H/C ratio bio-oil. Simplified descriptions of dehydration and decarboxylation reactions ca...
0
Organic Chemistry
In organometallic chemistry, a metallacycle is a derivative of a carbocyclic compound wherein a metal has replaced at least one carbon center; this is to some extent similar to heterocycles. Metallacycles appear frequently as reactive intermediates in catalysis, e.g. olefin metathesis and alkyne trimerization. In organ...
0
Organic Chemistry
The arrangement of the continents has changed over time due to plate tectonics, resulting in the bathymetry of ocean basins also changing over time. The shape and size of the basins influences the circulation patterns and concentration of nutrients within them. Numerical models simulating past arrangements of continent...
9
Geochemistry
Carbon-14 is produced in coolant at boiling water reactors (BWRs) and pressurized water reactors (PWRs). It is typically released to the atmosphere in the form of carbon dioxide at BWRs, and methane at PWRs. Best practice for nuclear power plant operator management of carbon-14 includes releasing it at night, when plan...
9
Geochemistry
Freiherr Christian Johann Dietrich Theodor von Grotthuss (20 January 1785 – 26 March 1822) was a Baltic German scientist known for establishing the first theory of electrolysis in 1806 and formulating the first law of photochemistry in 1817. His theory of electrolysis is considered the first description of the so-calle...
5
Photochemistry
The HiFIT hammer operates with a hardened pin with a ball resting on the workpiece with a diameter D of 3 mm. This pin is hammered with an adjustable intensity at around 180–300 Hz at the weld toe. Local mechanical deformations occur in the form of a treatment track. The weld toe is deformed plastically. The induced co...
8
Metallurgy
The concept of potential energy surface was very important in the development of TST. The foundation of this concept was laid by René Marcelin in 1913. He theorized that the progress of a chemical reaction could be described as a point in a potential energy surface with coordinates in atomic momenta and distances. In 1...
7
Physical Chemistry
Until recent decades it was common to assume that the release of hydrogen and oxygen gas during electrolysis of water always has a Faraday efficiency of 100%. Pons and Fleischmann, and other investigators who reported the finding of anomalous excess heat in electrolytic cells, all relied on this popular assumption. No ...
7
Physical Chemistry
This pathway is a part of the glutamate family of amino acid biosynthetic pathways. The reaction steps in the pathway are similar to the citric acid cycle. The first step in the pathway is condensation of acetyl-CoA with α-ketoglutarate, which gives homocitrate. This reaction is catalyzed by homocitrate synthase. Homoc...
1
Biochemistry
Chitin (CHON) ( ) is a long-chain polymer of N-acetylglucosamine, an amide derivative of glucose. Chitin is the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chitin are produced each year in the biosphere. It is a primary component of cell walls in fungi (especial...
1
Biochemistry
A variety of oxygen-transport and -binding proteins exist in organisms throughout the animal and plant kingdoms. Organisms including bacteria, protozoans, and fungi all have hemoglobin-like proteins whose known and predicted roles include the reversible binding of gaseous ligands. Since many of these proteins contain g...
7
Physical Chemistry
When building on top of bay mud layers or when dredging estuary bottoms, a variety of regulatory frameworks may arise. Normally in the United States, an Environmental Impact Report as well as a geotechnical investigation are conducted precedent to any major construction over bay mud. Combined, these reports have devel...
2
Environmental Chemistry
In a plasma, a Coulomb collision rarely results in a large deflection. The cumulative effect of the many small angle collisions, however, is often larger than the effect of the few large angle collisions that occur, so it is instructive to consider the collision dynamics in the limit of small deflections. We can consid...
7
Physical Chemistry
21st Century Medicine (21CM) is a California cryobiological research company which has as its primary focus the development of perfusates and protocols for viable long-term cryopreservation of human organs, tissues and cells at temperatures below −100 °C through the use of vitrification. 21CM was founded in 1993. In 20...
1
Biochemistry
With the development of native chemical ligation in 1994, total chemical synthesis of pairs of D-protein and L-protein enantiomers became feasible. In the first practical application to solving an unknown structure, racemic and quasi-racemic X-ray crystallography were used to determine the structure of snow flea anti-f...
3
Analytical Chemistry
The Kurnakov test is sometimes used to detect transplatin in samples of the drug cisplatin. In hot aqueous solution, the cis-compound reacts with aqueous thiourea (tu) to give a deeper yellow solution, from which yellow needles of [Pt(tu)]Cl chloride deposit on cooling. The trans-compound gives a colourless solution, f...
3
Analytical Chemistry
Ted Ellis is involved with various causes and charitable organizations including United Way, ICLS, African American Visual Arts Association, Jack and Jill of America Inc., the United Negro College Fund, Heritage Christian Academy, and various public school districts. He was the featured artist of Big Brothers Big Siste...
3
Analytical Chemistry
Volatile acyl halides are lachrymatory because they can react with water at the surface of the eye producing hydrohalic and organic acids irritating to the eye. Similar problems can result if one inhales acyl halide vapors. In general, acyl halides (even non-volatile compounds such as tosyl chloride) are irritants to t...
0
Organic Chemistry
Dihalophospaalkenes of the general form R-P=CX, where X is Cl, Br, or I, undergo lithium-halogen exchange with organolithium reagents to yield intermediates of the form R-P=CXLi. These species then eject the corresponding lithium halide salt, LiX, to putatively give a phospha-isocyanide, which can rearrange, much in th...
0
Organic Chemistry
Transcriptome instability is a genome-wide, pre-mRNA splicing-related characteristic of certain cancers. In general, pre-mRNA splicing is dysregulated in a high proportion of cancerous cells. For certain types of cancer, like in colorectal and prostate, the number of splicing errors per cancer has been shown to vary g...
1
Biochemistry
In a recent publication, REMS technology has received the attention of the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases ([http://www.esceo.org/ ESCEO]). In this work, all the available technologies for bone strength assessment and fracture risk estimat...
7
Physical Chemistry
Germanns first scholarly publications reported his undergraduate electrochemistry research under the direction of Frank Curry Mathers (1881–1973). His M.Sc. research at Wisconsin was with Joseph Howard Mathews (1881–1970). His Sc.D. thesis was published as Albert-F.-O. Germann, Révision de la densité de loxygène, contr...
7
Physical Chemistry
Stability is among the essential properties of a CRM (see definitions above), and stability assessment is accordingly required for certified reference materials. Stability under long term storage and also under conditions of transport are both expected to be assessed. "Assessment" is not synonymous with "testing"; some...
3
Analytical Chemistry
In a flat horizontal uniformly layered radiative field, the hemispheric fluxes, upwards and downwards, at a point, can be subtracted to yield what is often called the net flux. The net flux then has a value equal to the magnitude of the full spherical flux vector at that point, as described above.
7
Physical Chemistry
This compound is prepared by oxidation of 4-aminodimethylaniline in the presence of sodium thiosulfate to give the quinonediiminothiosulfonic acid, reaction with dimethylaniline, oxidation to the indamine, and cyclization to give the thiazine: A green electrochemical procedure, using only dimethyl-4-phenylenediamine an...
3
Analytical Chemistry
The active zone is present in all chemical synapses examined so far and is present in all animal species. The active zones examined so far have at least two features in common, they all have protein dense material that project from the membrane and tethers synaptic vesicles close to the membrane and they have long fil...
1
Biochemistry
The radical-pair mechanism explains how a magnetic field can affect reaction kinetics by affecting electron spin dynamics. Most commonly demonstrated in reactions of organic compounds involving radical intermediates, a magnetic field can speed up a reaction by decreasing the frequency of reverse reactions.
7
Physical Chemistry
The Soviet Alfa-class submarines used LBE as a coolant for their nuclear reactors throughout the Cold War. OKB Gidropress (the Russian developers of the VVER-type Light-water reactors) has expertise in LBE reactors. The SVBR-75/100, a modern design of this type, is one example of the extensive Russian experience with t...
8
Metallurgy
Multipoles beyond the quadrupole can correct for spherical aberration and in particle accelerators the dipole bending magnets are really composed of a large number of elements with different superpositions of multipoles. Usually the dependency is given for the kinetic energy itself depending on the power of the velocit...
7
Physical Chemistry
Strychnine total synthesis in chemistry describes the total synthesis of the complex biomolecule strychnine. The first reported method by the group of Robert Burns Woodward in 1954 is considered a classic in this research field. At the time it formed the natural conclusion to an elaborate process of molecular structure...
0
Organic Chemistry
Like its relative [[annulene|[12]annulene]], hexadehydro-[12]annulene is also antiaromatic. Its structure has been studied computationally via ab initio and density functional theory calculations and is confirmed to be antiaromatic.
7
Physical Chemistry
In 2013, Dr. Earle McBride, a researcher studying sandstone diagenesis and the textual and compositional maturation of sand during transportation, mixed samples collected from Omaha Beach in 1988 with a blue epoxy, creating an "artificial sandstone", before slicing it into thin sections. Utilising an optical microscope...
2
Environmental Chemistry
Repressor proteins bind to the DNA strand and prevent RNA polymerase from being able to attach to the DNA and synthesize mRNA. Inducers bind to repressors, causing them to change shape and preventing them from binding to DNA. Therefore, they allow transcription, and thus gene expression, to take place. For a gene to be...
0
Organic Chemistry
When a crystal is composed of crystallites with varying lattice orientation, topographic contrast arises: In plane-wave topography, only selected crystallites will be in diffracting position, thus yielding diffracted intensity only in some parts of the image. Upon sample rotation, these will disappear, and other crysta...
3
Analytical Chemistry
Light-harvesting complex I is permanently bound to photosystem I via the plant-specific subunit PsaG. It is made up of four proteins: Lhca1, Lhca2, Lhca3, and Lhca4, all of which belong to the LHC or chlorophyll a/b-binding family. The LHC wraps around the PS1 reaction core.
5
Photochemistry
New technologies in genomics have changed the way researchers approach both basic and translational research. With approaches such as exome sequencing, it is possible to significantly enhance the data generated from individual genomes which has put forth a series of questions on how to deal with the vast amount of info...
1
Biochemistry
To determine the energy levels, the polygon corresponding to the cyclic annulene is desired is inscribed in the circle of radius 2β and centered at α (the energy of an isolated p orbital). The y-coordinate of the vertices of the polygon are the simple Hückel theory orbital energies. For systems with Hückel topology, th...
7
Physical Chemistry
The test was used in forensics for many years to test for the traces of nitroglycerine. Caustic soda is used to break down sample containing nitroglycerine to produce nitrite ions. The test involves the taking of a sample with ether and its division into two bowls. Caustic soda is added to the first bowl followed by t...
3
Analytical Chemistry
Different types of corrosion inhibitor exist. Among them, oxidizing species such as chromate () and nitrite () were the first used to re-establish the state of passivation in the protective oxide layer. In the specific case of steel, the cation being a relatively soluble species, it contributes to favor the dissolutio...
8
Metallurgy