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Entropic gravity, also known as emergent gravity, is a theory in modern physics that describes gravity as an entropic force—a force with macro-scale homogeneity but which is subject to quantum-level disorder—and not a fundamental interaction. The theory, based on string theory, black hole physics, and quantum informati...
7
Physical Chemistry
The importance of motor proteins in cells becomes evident when they fail to fulfill their function. For example, kinesin deficiencies have been identified as the cause for Charcot-Marie-Tooth disease and some kidney diseases. Dynein deficiencies can lead to chronic infections of the respiratory tract as cilia fail to f...
6
Supramolecular Chemistry
Optical transitions must preserve the total spin and occur only between levels of the same total spin. Specifically, transitions between the ground and excited states (with equal spin) can be induced using a green laser with a wavelength of 546 nm. Transitions E→A and E→A are non-radiative, while A →E has both a non-ra...
7
Physical Chemistry
Relaxivities, nuclear relaxation rates, line shape and other parameters were reported useful in structural studies of carbohydrates.
0
Organic Chemistry
The lac operon in the prokaryote E. coli consists of genes that produce enzymes to break down lactose. Its operon is an example of a prokaryotic silencer. The three functional genes in this operon are lacZ, lacY, and lacA. The repressor gene, lacI, will produce the repressor protein LacI which is under allosteric regul...
1
Biochemistry
Since a variety of systems have been investigated, a study was done to investigate the individual adsorption of a mixed solution. This phenomenon is also called competitive adsorption because solutes tend to compete for the same adsorption sites. In the experiment conducted by Rosene and Manes, the competitive adsorpti...
7
Physical Chemistry
The working of memorial brasses is generally considered to have originated in north-western Germany, at least one centre being Cologne, where were manufactured the latten or Cullen plates for local use and for exportation. But it is certain that from medieval times there was an equal production in the towns of Belgium,...
8
Metallurgy
In C4 plants, sodium is a micronutrient that aids in metabolism, specifically in regeneration of phosphoenolpyruvate (involved in the biosynthesis of various aromatic compounds, and in carbon fixation) and synthesis of chlorophyll. In others, it substitutes for potassium in several roles, such as maintaining turgor pre...
1
Biochemistry
This explanation proposes that a stable product could contribute to the alpha effect, however, this factor could not be the sole factor.
7
Physical Chemistry
Max Planck derived a formula to describe the electromagnetic field inside a box when in thermal equilibrium in 1900. His model consisted of a superposition of standing waves. In one dimension, the box has length L, and only sinusoidal waves of wavenumber can occur in the box, where n is a positive integer (mathematical...
7
Physical Chemistry
Induction of proliferation by the EpoR is likely cell type-dependent. It is known that EpoR can activate mitogenic signaling pathways and can lead to cell proliferation in erythroleukemic cell lines in vitro, various non-erythroid cells, and cancer cells. So far, there is no sufficient evidence that in vivo, EpoR signa...
1
Biochemistry
* Aronson, S. and Ludlam, T.: [https://searchworks.stanford.edu/view/11327941 "Hunting the quark gluon plasma"], U.S. Dept. of Energy (2005) * Letessier, Jean: [https://searchworks.stanford.edu/view/4807502 Hadrons and quark-gluon plasma], Cambridge monographs on particle physics, nuclear physics, and cosmology (Vol. 1...
7
Physical Chemistry
The principal natural phenomena that contribute acid-producing gases to the atmosphere are emissions from volcanoes. Thus, for example, fumaroles from the Laguna Caliente crater of Poás Volcano create extremely high amounts of acid rain and fog, with acidity as high as a pH of 2, clearing an area of any vegetation and ...
2
Environmental Chemistry
This classification, based on the effects on behavior, remains artificial. Pheromones fill many additional functions. * Nasonov pheromones (worker bees) * Royal pheromones (bees) * Calming (appeasement) pheromones (mammals) * Necromones, given off by a deceased and decomposing organism; consisting of oleic and linoleic...
1
Biochemistry
The SUPERFAMILY database has numerous research applications and has been used by many research groups for various studies. It can serve either as a database for proteins that the user wishes to examine with other methods, or to assign a function and structure to a novel or uncharacterized protein. One study found SUPER...
1
Biochemistry
The size and strength of the induced vortices around a conducting particle have direct relationship with the applied electric filed and also the size of the conducted surface. This phenomenon is experimentally and numerically proven by several studies. The vortices grow as the external electric field increases and gene...
7
Physical Chemistry
ESI interface for LC–MS systems was developed by Fenn and collaborators in 1988. This ion source/ interface can be used for the analysis of moderately polar and even very polar molecules (e.g., metabolites, xenobiotics, peptides, nucleotides, polysaccharides). The liquid eluate coming out of the LC column is directed i...
3
Analytical Chemistry
Hexamethyldisilazane is employed as a reagent in many organic reactions: 1) HMDS is used as a reagent in condensation reactions of heterocyclic compounds such as in the microwave synthesis of a derivative of xanthine: 2) The HMDS mediated trimethylsilylation of alcohols, thiols, amines and amino acids as protective gr...
0
Organic Chemistry
A number of chelators of divalent cations have different fluorescence spectra in the bound and unbound states. Chelators for Ca are well established, have high affinity for the cation, and low interference from other ions. Mg chelators lag behind and the major fluorescence dye for Mg (mag-fura 2) actually has a higher ...
1
Biochemistry
The digestive system is supplied by the celiac artery. The celiac artery is the first major branch from the abdominal aorta, and is the only major artery that nourishes the digestive organs. There are three main divisions – the left gastric artery, the common hepatic artery and the splenic artery. The celiac artery sup...
1
Biochemistry
Consider the set of active centers (fig.1.). Assume fast transition between sublevels within each level, and slow transition between levels. According to the McCumber hypothesis, the cross-sections and do not depend on the populations and . Therefore, we can deduce the relation, assuming the thermal state. Let be g...
7
Physical Chemistry
Alternative splicing was first observed in 1977. The adenovirus produces five primary transcripts early in its infectious cycle, prior to viral DNA replication, and an additional one later, after DNA replication begins. The early primary transcripts continue to be produced after DNA replication begins. The additional p...
1
Biochemistry
Gene expression is regulated by histone acetylation and deacetylation, and this regulation is also applicable to inflammatory genes. Inflammatory lung diseases are characterized by expression of specific inflammatory genes such as NF-κB and AP-1 transcription factor. Treatments with corticosteroids and theophylline for...
0
Organic Chemistry
* First position – primary direction – z direction, assigned to the higher-order axis. * Second position – symmetrically equivalent secondary directions, which are perpendicular to the z-axis. These can be 2, m, or * Third position – symmetrically equivalent tertiary directions, passing between secondary directions....
3
Analytical Chemistry
Post-mortem diagnosis is the use of post-mortem chemistry analysis tests to diagnose a disease after someone has died. Some diseases are unknown until death, or were not correctly diagnosed earlier. One way that diseases can be diagnosed is by examining the concentrations of certain substances in the blood or other sam...
1
Biochemistry
There have also been limited studies on using these materials in robotics, for example the hobbyist robot Stiquito (and "Roboterfrau Lara"), as they make it possible to create very lightweight robots. Recently, a prosthetic hand was introduced by Loh et al. that can almost replicate the motions of a human hand [Loh2005...
8
Metallurgy
Free triiodothyronine (fT or free T3) is generally elevated in hyperthyroidism and decreased in hypothyroidism. Reference ranges depend on the method of analysis. Results should always be interpreted using the range from the laboratory that performed the test. Example values are:
1
Biochemistry
A particularly vexing question in the study of the chemical origins of life is the selection of ribose, which forms the backbone of the nucleic acids found in modern biological systems. Eschenmoser's work on a variant of the formose reaction that produces phosphorylated ribose in relatively significant concentrations h...
0
Organic Chemistry
In chemical synthesis, click chemistry is a class of simple, atom-economy reactions commonly used for joining two molecular entities of choice. Click chemistry is not a single specific reaction, but describes a way of generating products that follow examples in nature, which also generates substances by joining small m...
0
Organic Chemistry
In biochemistry, activation, specifically called bioactivation, is where enzymes or other biologically active molecules acquire the ability to perform their biological function, such as inactive proenzymes being converted into active enzymes that are able to catalyze their substrates reactions into products. Bioactivat...
7
Physical Chemistry
In 2005 and again in 2011, the compound was prepared by total synthesis together with the unstrained compound riccardin C. In 2013, several other syntheses were reported for it and a racemic synthesis.
0
Organic Chemistry
When used as an indicator in an EDTA titration, the characteristic blue end-point is reached when sufficient EDTA is added and the metal ions bound to the indicator are chelated by EDTA, leaving the free indicator molecule. Eriochrome Black T has also been used to detect the presence of rare earth metals.
3
Analytical Chemistry
The main function of glycolipids in the body is to serve as recognition sites for cell–cell interactions. The saccharide of the glycolipid will bind to a specific complementary carbohydrate or to a lectin (carbohydrate-binding protein), of a neighboring cell. The interaction of these cell surface markers is the basis o...
0
Organic Chemistry
*France–Japan: TOULOUSE–NARA, Toulouse III - Paul Sabatier University. CEMES (CNRS) and Nara Institute of Science and Technology. *United States–Austria: Rice–Graz nanoprix, Rice University and University of Graz *Germany: GAZE, Technische Universitat Dresden *United States: Ohio Bobcat Nanowagon, Ohio University *Fran...
6
Supramolecular Chemistry
As discussed previously, the 4n rule mainly deals with clusters with electron counts of , in which approximately 4 electrons are on each vertex. As more electrons are added per vertex, the number of the electrons per vertex approaches 5. Rather than adopting structures based on deltahedra, the 5n-type clusters have str...
7
Physical Chemistry
Phosphorus tribromide is a colourless liquid with the formula PBr. The liquid fumes in moist air due to hydrolysis and has a penetrating odour. It is used in the laboratory for the conversion of alcohols to alkyl bromides.
0
Organic Chemistry
In optics, Lamberts cosine law says that the radiant intensity or luminous intensity observed from an ideal diffusely reflecting surface or ideal diffuse radiator is directly proportional to the cosine of the angle θ between the observers line of sight and the surface normal; . The law is also known as the cosine emiss...
7
Physical Chemistry
The concept of a reversible reaction was introduced by Claude Louis Berthollet in 1803, after he had observed the formation of sodium carbonate crystals at the edge of a salt lake (one of the natron lakes in Egypt, in limestone): :2NaCl + CaCO → NaCO + CaCl He recognized this as the reverse of the familiar reaction : N...
7
Physical Chemistry
The term "representative layer" refers to a hypothetical plane parallel layer that has properties relevant to absorption spectroscopy that are representative of a sample as a whole. For particulate samples, a layer is representative if each type of particle in the sample makes up the same fraction of volume and surface...
7
Physical Chemistry
The paradigm of toxicological assessment of benzene is shifting towards the domain of molecular toxicology as it allows understanding of fundamental biological mechanisms in a better way. Glutathione seems to play an important role by protecting against benzene-induced DNA breaks and it is being identified as a new bio...
2
Environmental Chemistry
In one of the earlier studies conducted by Manes, M., & Hofer, L. J. E., the Polyani theory was used to characterize liquid-phase adsorption isotherms on various concentrations activated carbon using a wide range of organic solvent. The polyani theory was shown to be a good fit for these various systems. Because of the...
7
Physical Chemistry
The expansive force of rusting, which may be called oxide jacking or rust burst, is a phenomenon that can cause damage to structures made of stone, masonry, concrete or ceramics, and reinforced with metal components. A definition is "the displacement of building elements due to the expansion of iron and steel products...
8
Metallurgy
Spectral absorbance in frequency and spectral absorbance in wavelength of a material, denoted and respectively, are given by where * is the spectral radiant flux in frequency by that material; * is the spectral radiant flux in frequency by that material; * is the spectral transmittance in frequency of that mater...
7
Physical Chemistry
While kinematical diffraction is adequate to understand the geometry of the diffraction spots, it does not correctly give the intensities and has a number of other limitations. For a more complete approach one has to include multiple scattering of the electrons using methods that date back to the early work of Hans Bet...
7
Physical Chemistry
Creatinine was first synthesized in vitro by Ivan Horbaczewski in 1885. One year later, Jaffes research was published in the paper Über den Niederschlag, welchen Pikrinsäre in normalem Harn erzeugt und über eine neue Reaction des Kreatinins. Jaffe had noticed that, when mixed in a sodium hydroxide (NaOH) solution, picr...
1
Biochemistry
The lower heating value (LHV; net calorific value; NCV, or lower calorific value; LCV) is another measure of available thermal energy produced by a combustion of fuel, measured as a unit of energy per unit mass or volume of substance. In contrast to the HHV, the LHV considers energy losses such as the energy used to va...
7
Physical Chemistry
The virial equation is especially useful to describe the causes of non-ideality at a molecular level (very few gases are mono-atomic) as it is derived directly from statistical mechanics: Where the coefficients in the numerator are known as virial coefficients and are functions of temperature. The virial coefficients a...
7
Physical Chemistry
The use of EAFs allows steel to be made from a 100% scrap metal feedstock. This greatly reduces the energy required to make steel when compared with primary steelmaking from ores. Another benefit is flexibility: while blast furnaces cannot vary their production by much and can remain in operation for years at a time, E...
8
Metallurgy
Tim Requarth, reviewing The Vital Question for The New York Times, finds the book "seductive and often convincing, though speculation far outpaces evidence in many of the book’s passages. But perhaps for a biological theory of everything, that's to be expected, even welcomed." Peter Forbes, reviewing The Vital Question...
1
Biochemistry
The synthesis consists of three steps. In the first step, 2-iodobenzoic acid is oxidized by sodium periodate and cyclized to 1-hydroxy-1,2-benziodoxol-3(1H)-one. The target compound can then be obtained by acylation with acetic anhydride and subsequent substitution reaction with trifluoromethyltrimethylsilane. Alternat...
0
Organic Chemistry
Yuri Alfredovich Berlin (, born Moscow, USSR, December 12, 1944) is an American physical chemist of Soviet origin. He is a research professor in the department of chemistry at Northwestern University.
7
Physical Chemistry
Niludipine is a calcium channel blocker of the dihydropyridine class. It is a vasodilator that acts upon the coronary arteries of the heart-lung. It was found to produce a calcium antagonistic effect on the smooth muscle of hearts of canines and guinea pigs inhibiting myocardial oxidative metabolism.
1
Biochemistry
Liquid-phase epitaxy (LPE) is a method to grow semiconductor crystal layers from the melt on solid substrates. This happens at temperatures well below the melting point of the deposited semiconductor. The semiconductor is dissolved in the melt of another material. At conditions that are close to the equilibrium between...
3
Analytical Chemistry
Transcriptomic biomarkers analyze all RNA molecules, not solely the exome. Transcriptomic biomarkers reveal the molecular identity and concentration of RNA in a specific cell or population. Pattern-based RNA expression analysis provides increased diagnostic and prognostic capability in predicting therapeutic responses...
1
Biochemistry
* H. J. M. Bowen, Trace Elements in Biochemistry. Academic Press, 1966. * H. J. M. Bowen, Properties of Solids and their Structures. McGraw-Hill, 1967. * H. J. M. Bowen, Environmental Chemistry of the Elements. Academic Press, 1979. .
3
Analytical Chemistry
MLST is highly unambiguous and portable. Materials required for ST determination can be exchanged between laboratories. Primer sequences and protocols can be accessed electronically. It is reproducible and scalable. MLST is automated, combines advances in high throughput sequencing and bioinformatics with established p...
1
Biochemistry
Plants deficient in the IMMUTANS gene that encodes the oxidase are especially susceptible to photooxidative stress during early plastid development. The knockout plants exhibit a phenotype of variegated leaves with white patches that indicate a lack of pigmentation or photodamage. This effect is enhanced with increased...
5
Photochemistry
Willard and his wife Margaret had two daughters, Ann and Nancy. Willard was a photography enthusiast and hobbyist who occasionally sold his work. He died in Ann Arbor, Michigan, on May 7, 1974. Michigan holds a named professorship in his honor; the current Willard Professor of Chemistry is Robert T. Kennedy.
3
Analytical Chemistry
One structural consequence of acyclic systems due to the stereoelectronic effect is the gauche effect. In 1,2-difluoroethane, despite the steric clash, the preferred conformation is the gauche one because σ(C–H) is a good donor and σ*(C–F) is a good acceptor and the stereoelectronic effect (σ(C–H) → σ*(C–F)) requires t...
4
Stereochemistry
The Lely method produces bulk silicon carbide crystals through the process of sublimation. Silicon carbide powder is loaded into a graphite crucible, which is purged with argon gas and heated to approximately . The silicon carbide near the outer walls of the crucible sublimes and is deposited on a graphite rod near the...
3
Analytical Chemistry
The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to electrons making a transition from a high energy state to a lower energy state. The photon energy of the emitted photons is equal to the energy difference between the two states. T...
7
Physical Chemistry
The attack takes the form of a reaction between ammonia and copper to form the cuprammonium ion, formula [Cu(NH)], a chemical complex which is water-soluble, and hence washed from the growing cracks. The problem of cracking can therefore also occur in copper and any other copper alloy, such as bronze. The tendency of c...
8
Metallurgy
Two binary solutions of different compositions or even two pure components can be mixed with various mixing ratios by masses, moles, or volumes. The mass fraction of the resulting solution from mixing solutions with masses m and m and mass fractions w and w is given by: where m can be simplified from numerator and deno...
3
Analytical Chemistry
In nerve terminals, synaptic vesicles are produced quickly to compensate for their rapid depletion during neurotransmitter release. Their biogenesis involves segregating synaptic vesicle membrane proteins from other cellular proteins and packaging those distinct proteins into vesicles of appropriate size. Besides, it e...
1
Biochemistry
Neurophysins are carrier proteins which transport the hormones oxytocin and vasopressin to the posterior pituitary from the paraventricular and supraoptic nucleus of the hypothalamus, respectively. Inside the neurosecretory granules, the analogous neurophysin I and II form stabilizing complexes via covalent interaction...
1
Biochemistry
The safety profile of HMB in adult humans is based upon evidence from clinical trials in humans and animal studies. In humans, no adverse effects in young adults or older adults have been reported when HMB is taken in doses of 3 grams per day for up to a year. Studies on young adults taking 6 grams of HMB per day for u...
1
Biochemistry
The reddish color typical of tholins is characteristic of many Trans-Neptunian objects, including plutinos in the outer Solar System such as 28978 Ixion. Spectral reflectances of Centaurs also suggest the presence of tholins on their surfaces. The New Horizons exploration of the classical Kuiper belt object 486958 Arro...
9
Geochemistry
Using conventional FT technology the process ranges in carbon efficiency from 25 to 50 percent and a thermal efficiency of about 50% for CTL facilities idealised at 60% with GTL facilities at about 60% efficiency idealised to 80% efficiency.
0
Organic Chemistry
Many bacteria use the anaerobic pathway for synthesizing unsaturated fatty acids. This pathway does not utilize oxygen and is dependent on enzymes to insert the double bond before elongation utilizing the normal fatty acid synthesis machinery. In Escherichia coli, this pathway is well understood. * FabA is a β-hydroxyd...
1
Biochemistry
Esters react with strong oxidizing acids, which may cause a violent reaction that is sufficiently exothermic to ignite the esters and the reaction products. Heat is also generated by the interaction of esters with alkali solutions. Very flammable hydrogen gas is generated by mixing esters with alkali metals and ionic h...
0
Organic Chemistry
Bacteria utilize complex long helical proteins as chemoreceptors, permitting signals to travel long distances across the cell's membrane. Chemoreceptors allow bacteria to react to chemical stimuli in their environment and regulate their movement accordingly. In archaea, transmembrane receptors comprise only 57% of chem...
3
Analytical Chemistry
Mutations to coactivator genes leading to loss or gain of protein function have been linked to diseases and disorders such as birth defects, cancer (especially hormone dependent cancers), neurodevelopmental disorders and intellectual disability (ID), among many others. Dysregulation leading to the over- or under-expres...
1
Biochemistry
The Zeisel determination or Zeisel test is a chemical test for the presence of esters or ethers in a chemical substance. It is named after the Czech chemist Simon Zeisel (1854–1933). In a qualitative test a sample is first reacted with a mixture of acetic acid and hydrogen iodide in a test tube. The ensuing reaction re...
3
Analytical Chemistry
Common organosulfur compounds present in petroleum fractions at the level of 200–500 ppm. Common compounds are thiophenes, especially dibenzothiophenes. By the process of hydrodesulfurization (HDS) in refineries, these compounds are removed as illustrated by the hydrogenolysis of thiophene:
9
Geochemistry
Sea salt aerosol, which originally comes from sea spray, is one of the most widely distributed natural aerosols. Sea salt aerosols are characterized as non-light-absorbing, highly hygroscopic, and having coarse particle size. Some sea salt dominated aerosols could have a single scattering albedo as large as ~0.97. Due ...
9
Geochemistry
Hydrides containing deuterium are known as deuterides. Some deuterides, such as LiD, are important fusion fuels in thermonuclear weapons and useful moderators in nuclear reactors.
0
Organic Chemistry
Cer6 is a LTR retrotransposon that is described from sequencing data in the chromosome III of C. elegans.
1
Biochemistry
Allyl boronic esters engage in electrophilic allyl shifts very much like silicon pendant in the Sakurai reaction. In one study a diallylation reagent combines both:
0
Organic Chemistry
Carcinogenic cells undergo a metabolic rewiring during oncogenesis, and oncometabolites play an important role. In cancer, there are several reprogrammed metabolic pathways that help cells survive when nutrients are scarce: Aerobic glycolysis, an increase in glycolytic flux, also known as the Warburg effect, allows gly...
1
Biochemistry
Many compounds from first row of transition metal monoxides (MO), from TiO to NiO, have a rocksalt structure. The rock salt structure is generated by filling all octahedral sites with cations in an oxygen anion fcc array.
7
Physical Chemistry
Soluble cell adhesion molecules (sCAMs) are a class of cell adhesion molecule (CAMs - cell surface binding proteins) that may represent important biomarkers for inflammatory processes involving activation or damage to cells such as platelets and the endothelium. They include soluble isoforms of the cell adhesion molec...
1
Biochemistry
DNA supercoiling refers to the amount of twist in a particular DNA strand, which determines the amount of strain on it. A given strand may be "positively supercoiled" or "negatively supercoiled" (more or less tightly wound). The amount of a strand's supercoiling affects a number of biological processes, such as compact...
1
Biochemistry
Ionochromic materials exist in a wide range of molecules, including organic molecules, pH-sensitive dyes and indicators, and other color-changing compounds with chromophores. Some of these molecules include phthalides, fluorans, and leucotriarylmethanes.
3
Analytical Chemistry
Plants in the genus Humulus and Cannabis produce terpenophenolic metabolites, compounds that are meroterpenes. Phenolic lipids are long aliphatic chains bonded to a phenolic moiety.
0
Organic Chemistry
Because of the diffraction limit in the resolution of conventional lens-based microscopes, namely D = 0.61λ/nsinθ, the maximum resolution obtainable with an optical microscope is ~200 nm. A new type of lens using multiple scattering of light allowed to improve the resolution to about 100 nm. Several new microscopy tech...
7
Physical Chemistry
Highly crosslinked resins typically swell much less than the latter. The property that allows these types of resins to work efficiently lies in their porous properties. The reacting compound can diffuse through the porous layer of the resin to converge with the scavenger's functional group. These types of resins are ut...
0
Organic Chemistry
The production of the cannabinoids THC and CBD are a result of a series of chemical reactions, and are just two types of over a hundred that are known. Inside the transcriptomes of glandular trichomes in the cannabis plant, the pathway for cannabinoid production takes place. Beginning with the formation of 3,5,7-triox...
1
Biochemistry
Gram-positive bacteria use autoinducing peptides (AIP) as their autoinducers. When gram-positive bacteria detect high concentration of AIPs in their environment, that happens by way of AIPs binding to a receptor to activate a kinase. The kinase phosphorylates a transcription factor, which regulates gene transcription. ...
1
Biochemistry
A thermodynamic system consisting of a single phase in the absence of external forces, in its own internal thermodynamic equilibrium, is homogeneous. This means that the material in any small volume element of the system can be interchanged with the material of any other geometrically congruent volume element of the sy...
7
Physical Chemistry
The Hometrees (Kelutral in Navi) are great enough to house hundreds of clan members. The trees are honeycombed with natural hollows and alcoves in which the Navi sleep, eat, weave, dance, and celebrate their connection to Eywa. Adult Hometrees are more than tall, and roughly in diameter. The Omaticaya inhabit a Giant...
1
Biochemistry
The synthesis of pyrethrin I involves the esterification of (+)-trans-chrysanthemic acid with (S)-(Z)-pyrethrolone. One synthetic method for each of these is shown in the images below. Sobti and Dev of the Malti-Chem Research Centre in Nadesari, vadodara, India published this method for chrysanthemic acid in 1974. The ...
0
Organic Chemistry
1,2,4,5-Tetrachloro-3-nitrobenzene (tecnazene) is an organic compound with the formula . It is a colorless solid. A related isomer is 1,2,3,4-tetrachloro-5-nitrobenzene. It is used as a standard for quantitative analysis by nuclear magnetic resonance. 1,2,4,5-Tetrachloro-3-nitrobenzene is also a fungicide used to pre...
3
Analytical Chemistry
Ferrocene is a redox-active organometallic compound which can be incorporated into various monomers and used to make polymers which can be tethered onto a surface. Vinylferrocene (ferroceneylethene) can be prepared by a Wittig reaction and then polymerized to form polyvinylferrocene (PVFc), an analog of polystyrene. ...
7
Physical Chemistry
Conventional measurement of the EQE will give the efficiency of the overall device. However it is often useful to have a map of the EQE over large area of the device. This mapping provides an efficient way to visualize the homogeneity and/or the defects in the sample. It was realized by researchers from the Institute o...
7
Physical Chemistry
In 1965, a paper was published by two researchers of the Scientific Laboratory at the Ford Motor Company, P. D. Maker and R. W. Terhune, in which the CARS phenomenon was reported for the first time. Maker and Terhune used a pulsed ruby laser to investigate the third order response of several materials. They first pass...
3
Analytical Chemistry
Joseph H. Burckhalter was a chemist who worked in the field of isothiocyanate compounds. In 1995 he was inducted into the National Inventors Hall of Fame. Burckhalter is also a member of the Medicinal Chemistry Hall of Fame. Burckhalter earned a B.S. in chemistry from the University of South Carolina in 1934 and an M...
0
Organic Chemistry
The types of RNAs transcribed from RNA polymerase III include: *Transfer RNAs *5S ribosomal RNA *U6 spliceosomal RNA *RNase P and RNase MRP RNA *7SL RNA (the RNA component of the signal recognition particle) *Vault RNAs *Y RNA *SINEs (short interspersed repetitive elements) *7SK RNA *Several microRNAs *Several small nu...
1
Biochemistry
Membrane-introduction mass spectrometry (MIMS) is a method of introducing analytes into the mass spectrometer's vacuum chamber via a semi-permeable membrane. Usually a thin, gas-permeable, hydrophobic membrane is used, for example polydimethylsiloxane. Samples can be almost any fluid including water, air or sometimes...
3
Analytical Chemistry
The main application for air filters are combustion air to engines. The filter papers are transformed into filter cartridges, which then is fitted to a holder. The construction of the cartridges mostly requires that the paper is stiff enough to be self-supporting. A paper for air filters needs to be very porous and hav...
3
Analytical Chemistry
Operons occur primarily in prokaryotes but also rarely in some eukaryotes, including nematodes such as C. elegans and the fruit fly, Drosophila melanogaster. rRNA genes often exist in operons that have been found in a range of eukaryotes including chordates. An operon is made up of several structural genes arranged und...
1
Biochemistry