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Controlled substance yearly limits as well individual shipment limits United Kingdom There are no specific research exemptions in the Misuse of Drugs Act. However, the associated Misuse of Drug Regulations 2001 does exempt products containing less than 1 mg of a controlled substance (1 ug for lysergide and derivatives)... | https://en.wikipedia.org/wiki?curid=2471575 |
Controlled substance Germany The Gesetz über den Verkehr mit Betäubungsmitteln (Betäubungsmittelgesetz - BtMG) / (Law on the Traffic in Narcotic Drugs (Narcotics Act - BtMG) has a partial exemption that might apply to certain research areas. For each schedule the act allows for "the preparations of the substances liste... | https://en.wikipedia.org/wiki?curid=2471575 |
Chromium oxide may refer to: | https://en.wikipedia.org/wiki?curid=2475188 |
Alpha and beta carbon The alpha carbon (Cα) in organic molecules refers to the first carbon atom that attaches to a functional group, such as a carbonyl. The second carbon atom is called the beta carbon (Cβ), and the system continues naming in alphabetical order with Greek letters. The nomenclature can also be applied ... | https://en.wikipedia.org/wiki?curid=2475322 |
Alpha and beta carbon It is the backbone carbon before the carbonyl carbon atom in the molecule. Therefore, reading along the backbone of a typical protein would give a sequence of –[N—Cα—carbonyl C]– etc. (when reading in the N to C direction). The α-carbon is where the different substituents attach to each different ... | https://en.wikipedia.org/wiki?curid=2475322 |
Barking dog reaction The "Barking Dog" is an exothermic chemical reaction that results from the ignition of a mixture of carbon disulfide and nitrous oxide. When ignited in a cylindrical tube, the reaction produces a bright flash and a loud "woof" - reminiscent of a barking dog. In simple terms, the ‘Barking Dog’ react... | https://en.wikipedia.org/wiki?curid=2475942 |
Lead(II) chloride (data page) This page provides supplementary chemical data on lead(II) chloride. The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source such as SIRI, and follow its direction... | https://en.wikipedia.org/wiki?curid=2476612 |
Lambda transition The λ (lambda) universality class is a group in condensed matter physics. It regroups several systems possessing strong analogies, namely, superfluids, superconductors and smectics (liquid crystals). All these systems are expected to belong to the same universality class for the thermodynamic critical... | https://en.wikipedia.org/wiki?curid=2477282 |
Polymethylhydrosiloxane (PMHS) is a polymer with the general structure -(CH(H)Si-O)-. It is used in organic chemistry as a mild and stable reducing agent easily transferring hydrides to metal centers. A variety of related materials are available under the following CAS registry numbers 9004-73-3, 16066-09-4, 63148-57-2... | https://en.wikipedia.org/wiki?curid=2477685 |
Silex is any of various forms of ground stone. In modern contexts the word refers to a finely ground, nearly pure form of silica or silicate. In the late 16th century, it meant powdered or ground up "flints" (i.e. stones, generally meaning the class of "hard rocks") It was later used in 1787 when describing experiments... | https://en.wikipedia.org/wiki?curid=2478630 |
FLiNaK is the name of the ternary eutectic alkaline metal fluoride salt mixture LiF-NaF-KF (46.5-11.5-42 mol %). It has a melting point of 454 °C and a boiling point of 1570 °C. It is used as electrolyte for the electroplating of refractory metals and compounds like titanium, tantalum, hafnium, zirconium and their bori... | https://en.wikipedia.org/wiki?curid=2478755 |
FLiNaK This is in contrast to FLiBe, which in a 66-34 mol% mixture will be a chemically neutral mix, as fluorine ions from LiF are donated to BeF to create the tetrafluoroberyllate ion BeF. | https://en.wikipedia.org/wiki?curid=2478755 |
Loschmidt constant The "Loschmidt constant" or Loschmidt's number (symbol: "n") is the number of particles (atoms or molecules) of an ideal gas in a given volume (the number density). It is usually quoted at [standard temperature and pressure], the 2014 CODATA recommended value is per cubic metre at 0 °C and 1 atm and ... | https://en.wikipedia.org/wiki?curid=2481420 |
Loschmidt constant The precision to which the is currently known is limited entirely by the uncertainty in the value of the gas constant. Loschmidt did not actually calculate a value for the constant which now bears his name, but it is a simple and logical manipulation of his published results. James Clerk Maxwell desc... | https://en.wikipedia.org/wiki?curid=2481420 |
Loschmidt constant The equation reduces to: relating the diameter of a gas molecule to measurable phenomena. The number density, the constant which now bears Loschmidt's name, can be found by simply substituting the diameter of the molecule into the definition of the mean free path and rearranging: Instead of taking th... | https://en.wikipedia.org/wiki?curid=2481420 |
Kramers–Kronig relations The are bidirectional mathematical relations, connecting the real and imaginary parts of any complex function that is analytic in the upper half-plane. These relations are often used to calculate the real part from the imaginary part (or vice versa) of response functions in physical systems, be... | https://en.wikipedia.org/wiki?curid=2481686 |
Kramers–Kronig relations The residue theorem consequently states that The second term in the last expression is obtained using the theory of residues, more specifically the Sokhotski–Plemelj theorem. Rearranging, we arrive at the compact form of the Kramers–Kronig relations, The single formula_21 in the denominator wil... | https://en.wikipedia.org/wiki?curid=2481686 |
Kramers–Kronig relations Additionally, if we subject the system to an oscillatory force with a frequency much higher than its highest resonant frequency, there will be almost no time for the system to respond before the forcing has switched direction, and so the frequency response formula_31 will converge to zero as fo... | https://en.wikipedia.org/wiki?curid=2481686 |
Kramers–Kronig relations We transform the integral into one of definite parity by multiplying the numerator and denominator of the integrand by formula_45 and separating: Since formula_4 is odd, the second integral vanishes, and we are left with The same derivation for the imaginary part gives These are the in a form t... | https://en.wikipedia.org/wiki?curid=2481686 |
Kramers–Kronig relations There is, however, a unique amplitude-vs-phase relation in the special case of a minimum phase system, sometimes called the Bode gain-phase relation. The terms Bayard-Bode relations and Bayard-Bode theorem, after the works of Marcel Bayard (1936) and Hendrik Wade Bode (1945) are also used for e... | https://en.wikipedia.org/wiki?curid=2481686 |
Kramers–Kronig relations One might thereby, for example, look for ultraviolet (UV) absorption bands in a laboratory specimen of interstellar dust less than a 100 nm across, i.e. too small for UV spectroscopy. Although electron spectroscopy has poorer energy resolution than light spectroscopy, data on properties in visi... | https://en.wikipedia.org/wiki?curid=2481686 |
Blackwater (waste) Blackwater in a sanitation context denotes wastewater from toilets, which likely contains pathogens. Blackwater can contain feces, urine, water and toilet paper from flush toilets. Blackwater is distinguished from greywater, which comes from sinks, baths, washing machines, and other kitchen appliance... | https://en.wikipedia.org/wiki?curid=2481830 |
Blackwater (waste) However, if blackwater does not contain excess water, or if it receives primary treatment to de-water, then it is easily processed through composting. The heat produced by naturally occurring thermophilic microorganisms will heat the compost to over , and destroy potential pathogens. Blackwater gener... | https://en.wikipedia.org/wiki?curid=2481830 |
Photochromism is the reversible transformation of a chemical species between two forms by the absorption of electromagnetic radiation (photoisomerization), where the two forms have different absorption spectra. In plain language, this can be described as a reversible change of colour upon exposure to light. One of the ... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism Thus, photochromic units have been demonstrated as components of molecular switches. The coupling of photochromic units to enzymes or enzyme cofactors even provides the ability to reversibly turn enzymes "on" and "off", by altering their shape or orientation in such a way that their functions are either "... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism was discovered in the late 1880s, including work by Markwald, who studied the reversible change of color of 2,3,4,4-tetrachloronaphthalen-1(4H)-one in the solid state. He labeled this phenomenon "phototropy", and this name was used until the 1950s when Yehuda Hirshberg, of the Weizmann Institute of Scienc... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism Some of the most common processes involved in photochromism are pericyclic reactions, cis-trans isomerizations, intramolecular hydrogen transfer, intramolecular group transfers, dissociation processes and electron transfers (oxidation-reduction). Another requirement of photochromism is two states of the m... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism Sometimes, and particularly in the dye industry, the term "irreversible photochromic" is used to describe materials that undergo a permanent color change upon exposure to ultraviolet or visible light radiation. Because by definition photochromics are reversible, there is technically no such thing as an "i... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism In a perfect system, there would exist wavelengths that can be used to provide 1:0 and 0:1 ratios of the isomers, but in real systems this is not possible, since the active absorbance bands always overlap to some extent. In order to incorporate photochromics in working systems, they suffer the same issues... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism Some other compounds can be changed in their luminescence behavior, magnetic interaction of metal sites, or stability of metal-to-ligand coordination by photoisomerization of their photochromic parts. Photochromic molecules can belong to various classes: triarylmethanes, stilbenes, azastilbenes, nitrones,... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism Like most organic dyes they are susceptible to degradation by oxygen and free radicals. Incorporation of the dyes into a polymer matrix, adding a stabilizer, or providing a barrier to oxygen and chemicals by other means prolongs their lifetime. The "diarylethenes" were first introduced by Irie and have si... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism Quinones with good thermal stability have been prepared, and they also have the additional feature of redox activity, leading to the construction of many-state molecular switches that operate by a mixture of photonic and electronic stimuli. Many inorganic substances also exhibit photochromic properties, o... | https://en.wikipedia.org/wiki?curid=2482408 |
Photochromism The metastable states (O-bonded isomers) of this class often revert thermally to their respective ground states (S-bonded isomers), although a number of examples exhibit two-color reversible photochromism. Ultrafast spectroscopy of these compounds has revealed exceptionally fast isomerization lifetimes ra... | https://en.wikipedia.org/wiki?curid=2482408 |
Hydrogen iodide (data page) This page provides supplementary chemical data on hydrogen iodide. The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source such as SIRI, and follow its directions. E... | https://en.wikipedia.org/wiki?curid=2483116 |
Homoleptic In inorganic chemistry, a homoleptic chemical compound is a metal compound with all ligands identical. The term uses the "homo-" prefix to indicate that something is the same for all. Some compounds with names that suggest that they are homoleptic are in fact heteroleptic, because they have ligands in them w... | https://en.wikipedia.org/wiki?curid=2483141 |
Methyl red (2-("N","N"-dimethyl-4-aminophenyl) azobenzenecarboxylic acid), also called C.I. Acid Red 2, is an indicator dye that turns red in acidic solutions. It is an azo dye, and is a dark red crystalline powder. is a pH indicator; it is red in pH under 4.4, yellow in pH over 6.2, and orange in between, with a p"K" ... | https://en.wikipedia.org/wiki?curid=2483251 |
Methyl red Some enterics subsequently use the mixed acid pathway to metabolize pyruvic acid to other acids, such as lactic, acetic, and formic acids. These bacteria are called methyl-red positive and include "Escherichia coli" and "Proteus vulgaris". Other enterics subsequently use the butylene glycol pathway to metabo... | https://en.wikipedia.org/wiki?curid=2483251 |
Schottky effect The or field enhanced thermionic emission is a phenomenon in condensed matter physics named after Walter H. Schottky. In electron emission devices, especially electron guns, the thermionic electron emitter will be biased negative relative to its surroundings. This creates an electric field of magnitude ... | https://en.wikipedia.org/wiki?curid=2484577 |
Catalytic cycle In chemistry, a catalytic cycle is a multistep reaction mechanism that involves a catalyst. The catalytic cycle is the main method for describing the role of catalysts in biochemistry, organometallic chemistry, bioinorganic chemistry, materials science, etc. Since catalysts are regenerated, catalytic cy... | https://en.wikipedia.org/wiki?curid=2484769 |
Catalytic cycle Applications include olefin metathesis and hydrogenation. The metal oxides require some activating reagent, usually a reducing agent, to enter the catalytic cycle. Often catalytic cycles show the conversion of a precatalyst to the catalyst. Often a so-called sacrificial catalyst is also part of the reac... | https://en.wikipedia.org/wiki?curid=2484769 |
Non-covalent interaction A non-covalent interaction differs from a covalent bond in that it does not involve the sharing of electrons, but rather involves more dispersed variations of electromagnetic interactions between molecules or within a molecule. The chemical energy released in the formation of non-covalent inter... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction However, this particular interaction is easily broken upon addition to water, or other highly polar solvents. In water ion pairing is mostly entropy driven; a single salt bridge usually amounts to an attraction value of about ΔG =5 kJ/mol at an intermediate ion strength I, at I close to zero th... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction Pauling the strength of a hydrogen bond is essentially determined by the electrostatic charges. Measurements of thousands complexes in chloroform or carbontetrachloride have led to additive free energy increments for all kind of donor-acceptor combinations. Halogen bonding is a type of non-cova... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction Dipole–dipole interactions are electrostatic interactions between permanent dipoles in molecules. These interactions tend to align the molecules to increase attraction (reducing potential energy). Normally, dipoles are associated with electronegative atoms, including oxygen, nitrogen, sulfur, a... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction This approach causes the electrons of the non-polar molecule to be polarized toward or away from the dipole (or "induce" a dipole) of the approaching molecule. Specifically, the dipole can cause electrostatic attraction or repulsion of the electrons from the non-polar molecule, depending on ori... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction In this example, when one hexane molecule approaches another, a temporary, weak partially negative dipole on the incoming hexane can polarize the electron cloud of another, causing a partially positive dipole on that hexane molecule.In absence of solvents hydrocarbons such as hexane form crysta... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction The sandwich configuration is not nearly as stable of an interaction as the previously two mentioned due to high electrostatic repulsion of the electrons in the π orbitals. Cation–pi interaction sinvolve the positive charge of a cation interacting with the electrons in a π-system of a molecule.... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction This phenomenon leads to minimum exposed surface area of non-polar molecules to the polar water molecules (typically spherical droplets), and is commonly used in biochemistry to study protein folding and other various biological phenomenon. The effect is also commonly seen when mixing various o... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction Using the "lock and key model" of enzyme binding, a drug (key) must be of roughly the proper dimensions to fit the enzyme's binding site (lock). Using the appropriately sized molecular scaffold, drugs must also interact with the enzyme non-covalently in order to maximize binding affinity bindin... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction This phase is known as the hydrophobic collapse, when nonpolar non-covalent interactions exclude water from the interior of the developing 3D protein structure. After this initial "burst phase," more polar non-covalent interactions take over. Between 5 and 1000 milliseconds after protein foldin... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction Cofactors can be either organic or inorganic molecules which assist in the catalytic mechanism of the active enzyme. The strength with which a cofactor is bound to an enzyme may vary greatly; non-covalently bound cofactors are typically anchored by hydrogen bonds or electrostatic interactions. ... | https://en.wikipedia.org/wiki?curid=2485027 |
Non-covalent interaction The heat energy required for a compound to change from liquid to gas is associated with the energy required to break the intermolecular forces each molecule experiences in its liquid state. | https://en.wikipedia.org/wiki?curid=2485027 |
In-Methylcyclophane In-Methylcyclophanes are organic compounds and members of a larger family of cyclophanes. These compounds are used to study how chemical bonds in molecules adapt to strain. In-methylcyclophanes in particular have a methyl group in proximity to a benzene ring. This is only possible when both methyl g... | https://en.wikipedia.org/wiki?curid=2485859 |
In-Methylcyclophane 52 ppm for the methyl protons compared to that of 3.16 to 3.85 in the anthracene compound. The reason for this anomaly is that the methyl protons are in line with the aromatic ring current of the benzene ring and are therefore severely shielded, an effect similar to the nucleus-independent chemical ... | https://en.wikipedia.org/wiki?curid=2485859 |
Anserine (β-alanyl-"N"-methylhistidine) is a dipeptide containing β-alanine and 1-methylhistidine, and is a derivative of carnosine, which had been methylated. can be found in the skeletal muscle and brain of mammals and birds. Due to its presence in lean muscles, like fish and poultry, there have been recent studies s... | https://en.wikipedia.org/wiki?curid=2488531 |
Anserine In a recent study including an Alzheimer's model mice, the use of anserine reduced the inflammation of astrocytes, showing that treatment with anserine can improve memory loss. Similarly, to arrive at this conclusion, scientists stained pericytes from mouse and found that anserine treated mouse had greater sur... | https://en.wikipedia.org/wiki?curid=2488531 |
PH helmet The P helmet, and PHG helmet were early types of gas mask issued by the British Army in the First World War, to protect troops against chlorine, phosgene and tear gases. Rather than having a separate filter for removing the toxic chemicals, they consisted of a gas-permeable hood worn over the head which was t... | https://en.wikipedia.org/wiki?curid=2491779 |
Restriction site Restriction sites, or restriction recognition sites, are located on a DNA molecule containing specific (4-8 base pairs in length) sequences of nucleotides, which are recognized by restriction enzymes. These are generally palindromic sequences (because restriction enzymes usually bind as homodimers), an... | https://en.wikipedia.org/wiki?curid=2492332 |
Restriction site In the case of the example the AATTG would have a complementary pair of TTAAC which would reduce the functionality of the DNA ligase enzyme. Restriction sites can be used for multiple applications in molecular biology such as identifying restriction fragment length polymorphisms (RFLPs). Several databa... | https://en.wikipedia.org/wiki?curid=2492332 |
Chromium(III) oxide (or chromia) is an inorganic compound with the formula . It is one of the principal oxides of chromium and is used as a pigment. In nature, it occurs as the rare mineral eskolaite. has the corundum structure, consisting of a hexagonal close packed array of oxide anions with of the octahedral holes o... | https://en.wikipedia.org/wiki?curid=2492567 |
Chromium(III) oxide " is a precursor to the magnetic pigment chromium dioxide, by the following reaction: Along with many other oxides, it is used as a compound when polishing (also called stropping) the edges of knives, razors, surfaces of optical devices etc. on a piece of leather, balsa, cloth or other material. It ... | https://en.wikipedia.org/wiki?curid=2492567 |
Gas flare A gas flare, alternatively known as a flare stack, is a gas combustion device used in industrial plants such as petroleum refineries, chemical plants and natural gas processing plants. They are also common at oil or gas extraction sites having oil wells, gas wells, offshore oil and gas rigs and landfills. In ... | https://en.wikipedia.org/wiki?curid=2495757 |
Gas flare Most industrial plant flares have a vapor-liquid separator (also known as a knockout drum) upstream of the flare to remove any large amounts of liquid that may accompany the relieved gases. Steam is very often injected into the flame to reduce the formation of black smoke. When too much steam is added, a cond... | https://en.wikipedia.org/wiki?curid=2495757 |
Gas flare 3 × 10 cubic feet) of associated gas have been flared globally each year since at least the mid 1990s until 2020. In 2011, that was equivalent to about 25 percent of the annual natural gas consumption in the United States or about 30 per cent of the annual gas consumption in the European Union. At market, thi... | https://en.wikipedia.org/wiki?curid=2495757 |
Gas flare However, on a plant where the gas production rate is sufficient for direct use in an industrial process that could be classified as part of the circular economy, and that may include the generation of electricity, the production of natural gas quality biogas for vehicle fuel or for heating in buildings, dryin... | https://en.wikipedia.org/wiki?curid=2495757 |
Gas flare However, flaring emissions contributed to 270 MtCO in 2017 and reducing flaring emissions is key to avoid dangerous global warming. An increasing number of governments and industries are committing to eliminate flaring by 2030. Improperly operated flares may emit methane and other volatile organic compounds a... | https://en.wikipedia.org/wiki?curid=2495757 |
Gas flare Over the course of the months and years that the refinery was running a vast number of moths must have been killed, suggesting that plants could not be pollinated over a large area of forest". The Bhopal disaster exemplifies the consequences of a failure to flare escaping methyl isocyanate gas. The gas was re... | https://en.wikipedia.org/wiki?curid=2495757 |
Cosmoline is the genericized trademark for a common class of brown wax-like petroleum-based corrosion inhibitors, typically conforming to United States Military Standard MIL-C-11796C Class 3. They are viscous when freshly applied, have a slight fluorescence, and solidify over time and exposure to air. was developed by ... | https://en.wikipedia.org/wiki?curid=2496138 |
Cosmoline is also frequently applied to automotive disc brake rotors at the factory, to prevent corrosion inside the box before the rotor is placed into service on a vehicle. It is easily removed by spraying brake cleaner on the braking surfaces of the rotor. During World War II cosmoline was used to coat weapons, incl... | https://en.wikipedia.org/wiki?curid=2496138 |
Cosmoline Older cosmoline which has had air exposure usually solidifies after a few years, once its volatile hydrocarbon fraction evaporates and leaves behind only the waxy remainder. This solid wax does not readily wipe off. It can be removed with laborious scraping but leaves crumbs to be swept or vacuumed away. Appl... | https://en.wikipedia.org/wiki?curid=2496138 |
Cosmoline It has been reported that talcum powder can be used as an absorbent of by packing the powder around the item to be cleaned and applying sufficient heat to melt the solid film, allowing the compound to be wicked from the coated surface into the talcum, which can be scraped off more easily. | https://en.wikipedia.org/wiki?curid=2496138 |
Kinetic fractionation is an isotopic fractionation process that separates stable isotopes from each other by their mass during unidirectional processes. Biological processes are generally unidirectional and are very good examples of "kinetic" isotope reactions. All organisms preferentially use lighter isotopic species,... | https://en.wikipedia.org/wiki?curid=2497263 |
Kinetic fractionation Whereas equilibrium fractionation makes the vapor about 10 per mil (1%) depleted in O relative to the liquid water, kinetic fractionation enhances this fractionation and often makes vapor that is about 15 per mil (1.5%) depleted. Condensation occurs almost exclusively by equilibrium processes, and... | https://en.wikipedia.org/wiki?curid=2497263 |
Salen ligand Salen refers to a tetradentate C-symmetric ligand synthesized from salicylaldehyde (sal) and ethylenediamine (en). It may also refer to a class of compounds, which are structurally related to the classical salen ligand, primarily bis-Schiff bases. Salen ligands are notable for coordinating a wide range of ... | https://en.wikipedia.org/wiki?curid=2500045 |
Salen ligand Chiral “salen” ligands may be created by proper substitution of the diamine backbone, the phenyl ring, or both. An example is the ligand obtained by condensation of the C-symmetric "trans"-1,2-diaminocyclohexane with 3,5-di-"tert"-butylsalicylaldehyde. Chiral ligands may be used in asymmetric synthesis rea... | https://en.wikipedia.org/wiki?curid=2500045 |
Salen ligand These include the ligands abbreviated as salph, from the condensation of 1,2-phenylenediamine and salicylaldehyde, and "salqu", from the condensation of salicylaldehyde and "2-quinoxalinol". | https://en.wikipedia.org/wiki?curid=2500045 |
Baeyer–Drewson indigo synthesis The (1882) is an organic reaction in which indigo is prepared from 2-nitrobenzaldehyde and acetone The reaction is classified as an aldol condensation. As a practical route to indigo, this method was displaced by routes from aniline. In the English literature this reaction is usually cal... | https://en.wikipedia.org/wiki?curid=2504081 |
Phosphorus acid Phosphorus oxoacid is a generic name for any acid whose molecule consists of atoms of phosphorus, oxygen, and hydrogen. There is a potentially infinite number of such compounds. Some of them are unstable and have not been isolated, but the derived anions and organic groups are present in stable salts an... | https://en.wikipedia.org/wiki?curid=2504151 |
Phosphorus acid The single-bonded oxygen atoms that are not shared are completed with acidic hydrogen atoms. Their generic formula is HPO, where "n" is the number of phosphorus atoms and "x" is the number of fundamental cycles in the molecule's structure. These acids, and their esters and salts ("phosphates") include s... | https://en.wikipedia.org/wiki?curid=2504151 |
Biocatalysis refers to the use of living (biological) systems or their parts to speed up (catalyze) chemical reactions. In biocatalytic processes, natural catalysts, such as enzymes, perform chemical transformations on organic compounds. Both enzymes that have been more or less isolated and enzymes still residing insid... | https://en.wikipedia.org/wiki?curid=2505416 |
Biocatalysis More than one hundred years ago, biocatalysis was employed to do chemical transformations on non-natural man-made organic compounds, with the last 30 years seeing a substantial increase in the application of biocatalysis to produce fine chemicals, especially for the pharmaceutical industry. Since biocataly... | https://en.wikipedia.org/wiki?curid=2505416 |
Biocatalysis Typically enzymes display three major types of selectivity: These reasons, and especially the latter, are the major reasons why synthetic chemists have become interested in biocatalysis. This interest in turn is mainly due to the need to synthesize enantiopure compounds as chiral building blocks for Pharma... | https://en.wikipedia.org/wiki?curid=2505416 |
Biocatalysis The maximum yield in such kinetic resolutions is 50%, since a yield of more than 50% means that some of wrong isomer also has reacted, giving a lower enantiomeric excess. Such reactions must therefore be terminated before equilibrium is reached. If it is possible to perform such resolutions under condition... | https://en.wikipedia.org/wiki?curid=2505416 |
Biocatalysis In this way the S-enantiomer will continuously be consumed by the enzyme while the R-enantiomer accumulates. It is even possible to stereoinvert pure S to pure R. Recently, photoredox catalysis has been applied to biocatalysis, enabling unique, previously inaccessible transformations. Photoredox chemistry ... | https://en.wikipedia.org/wiki?curid=2505416 |
Biocatalysis Many types of PCs with a large range of redox potentials can be utilized, allowing for greater tunability of reactive compared to using a cofactor. Rose bengal, and external PC, was utilized in tandem with an oxioreductase to enantioselectively deacylate medium sized alpha-acyl-ketones. Using an external P... | https://en.wikipedia.org/wiki?curid=2505416 |
Triiodide In chemistry, triiodide usually refers to the triiodide ion, . This anion, one of the polyhalogen ions, is composed of three iodine atoms. It is formed by combining aqueous solutions of iodide salts and iodine. Some salts of the anion have been isolated, including thallium(I) triiodide (Tl[I]) and ammonium tr... | https://en.wikipedia.org/wiki?curid=2505643 |
Triiodide In the molecular orbital model, a common explanation for the hypervalent bonding on the central iodine involves a three-center four-electron bond. The I−I bond is longer than in diatomic iodine, I. In ionic compounds, the bond lengths and angles of triiodide vary depending on the nature of the cation. The tri... | https://en.wikipedia.org/wiki?curid=2505643 |
Triiodide The process is analogous to the reaction of S with sodium sulfide, except that the higher polyiodides have branched structures. | https://en.wikipedia.org/wiki?curid=2505643 |
Cleanroom suit A cleanroom suit, clean room suit, or bunny suit, is an overall garment worn in a cleanroom, an environment with a controlled level of contamination. One common type is an all-in-one coverall worn by semiconductor and nanotechnology line production workers, technicians, and process / equipment engineers,... | https://en.wikipedia.org/wiki?curid=2507132 |
Cleanroom suit Removal of the garments (into several barrels) is a complicated process which must be performed in an exact sequence. Often a health physicist is present in the work area to observe good anti-contamination practices. | https://en.wikipedia.org/wiki?curid=2507132 |
Perkin Medal The is an award given annually by the Society of Chemical Industry (American Section) to a scientist residing in America for an "innovation in applied chemistry resulting in outstanding commercial development." It is considered the highest honor given in the US chemical industry. The was first awarded in 1... | https://en.wikipedia.org/wiki?curid=2507834 |
Afwillite is a calcium hydroxide nesosilicate mineral with formula Ca(SiOOH)·2HO. It occurs as glassy, colorless to white prismatic monoclinic crystals. Its Mohs scale hardness is between 3 and 4. It occurs as an alteration mineral in contact metamorphism of limestone. It occurs in association with apophyllite, natroli... | https://en.wikipedia.org/wiki?curid=2508768 |
Afwillite has a complex monoclinic structure, and the silicon tetrahedra in the crystal structure are held together by hydrogen bonds. It has perfect cleavage parallel to its (101) and poor cleavage parallel to its (100) faces. It is biaxial and its 2V angle, the measurement from one optical axis to the other optical a... | https://en.wikipedia.org/wiki?curid=2508768 |
Afwillite The silicon tetrahedra are held together by the OH group and hydrogen bonding occurs between the hydrogen in the OH and the silicon tetrahedra. Hydrogen bonding is caused because the positive ion, hydrogen, is attracted to negatively charge ions which, in this case, are the silicon tetrahedra. is one of the c... | https://en.wikipedia.org/wiki?curid=2508768 |
List of phytochemicals in food While there is ample evidence to indicate the health benefits of diets rich in fruits, vegetables, legumes, whole grains and nuts, no specific food has been acknowledged by scientists and government regulatory authorities as providing a health benefit. Current medical research is focused ... | https://en.wikipedia.org/wiki?curid=2509774 |
Trimyristin is an ester with the chemical formula CHO. It is a saturated fat which is the triglyceride of myristic acid. is a white to yellowish-gray solid that is insoluble in water, but soluble in ethanol, benzene, chloroform, dichloromethane, and ether. is found naturally in many vegetable fats and oils. The isolati... | https://en.wikipedia.org/wiki?curid=2510384 |
Copper(I) thiophene-2-carboxylate or CuTC is a thiophene and a reagent in organic chemistry that especially promotes the Ullmann reaction between aryl halides. | https://en.wikipedia.org/wiki?curid=2515701 |
Glauber is a scientific discovery method written in the context of computational philosophy of science. It is related to machine learning in artificial intelligence. was written, among other programs, by Pat Langley, Herbert A. Simon, G. Bradshaw and J. Zytkow to demonstrate how scientific discovery may be obtained by ... | https://en.wikipedia.org/wiki?curid=2517899 |
Glauber The software were supplied with information about a variety of materials as they had been described by 17-18th century chemists, before most of modern chemical knowledge had been uncovered or invented. Qualitative descriptions like taste, rather than numerical data such as molecular weight, were programmed into... | https://en.wikipedia.org/wiki?curid=2517899 |
Glauber Here they do not mean the chemical structure of the substances, which was not known at the time of the discovery; the program works with any name used in the 17th century like "aqua regia", "muriatic acid", etc. is based in two procedures: Form-Class and Determine-Quantifier. The procedure Form-Class generalize... | https://en.wikipedia.org/wiki?curid=2517899 |
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