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Diphenylamine
Diphenylamine is an organic compound with the formula (C6H5)2NH. The compound is a derivative of aniline, consisting of an amine bound to two phenyl groups. The compound is a colorless solid, but commercial samples are often yellow due to oxidized impurities.P. F. Vogt, J. J. Gerulis, "Amines, Aromatic" in Ullmann’s Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim. Diphenylamine dissolves well in many common organic solvents, and is moderately soluble in water. It is used mainly for its antioxidant properties. Diphenylamine is widely used as an industrial antioxidant, dye mordant and reagent and is also employed in agriculture as a fungicide and antihelmintic. Preparation and reactivity Diphenylamine is produced by heating a mixture of aniline and anilinium chloride: : It is a weak base, with a ''K''b of 10−14. With strong acids, it forms salts. For example, treatment with sulfuric acid gives the bisulfate as a white or yellowish powder with m.p. . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Nitrodiphenylamine
2-Nitrodiphenylamine is an organic chemical with the formula . It is a nitration, nitrated derivative of diphenylamine. It is a red solid, usually found in form of flakes or powder. It is polar but hydrophobic. Diphenylamine is used to extend the shelf-life of explosives containing nitrocellulose or nitroglycerin. Such nitrated materials release nitrogen oxides, which deteriorate the device. The diphenylamine traps NO2, affording the title compound and related species. And the title compound further traps additional nitrogen oxides. One of its major uses is to control the explosion rate of propylene glycol dinitrate. As a stabilizer, its major role is to eliminate the acidic nitrates and nitrogen oxides produced by gradual decomposition of nitric acid esters, which would otherwise autocatalysis, autocatalyze further decomposition. Its amount is usually 1-2% of the mixture; higher amounts than 2% degrade the propellant's ballistic properties. The amount of the stabilizer deplete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smokeless Powder
Finnish smokeless powder Smokeless powder is a type of propellant used in firearms and artillery that produces less smoke and less fouling when fired compared to black powder. Because of their similar use, both the original black powder formulation and the smokeless propellant which replaced it are commonly described as gunpowder. The combustion products of smokeless powder are mainly gaseous, compared to around 55% solid products (mostly potassium carbonate, potassium sulfate, and potassium sulfide) for black powder. In addition, smokeless powder does not leave the thick, heavy fouling of hygroscopic material associated with black powder that causes rusting of the barrel. Despite its name, smokeless powder is not completely free of smoke; while there may be little noticeable smoke from small-arms ammunition, smoke from artillery fire can be substantial. Invented in 1884 by Paul Vieille, the most common formulations are based on nitrocellulose, but the term was also used to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dische Test
The Dische test, or Dische reaction, is used to distinguish DNA from RNA. It was invented by Zacharias Dische. Method Dische's diphenylamine reagent consists of diphenylamine, glacial acetic acid, sulfuric acid, and ethanol. When heated with DNA, it turns blue in the presence of DNA. A more intense blue color indicates a greater concentration of DNA. Mechanism The acid converts deoxyribose to a molecule that binds with diphenylamine to form a blue substance. The reagent does not interact with RNA, so can be used to distinguish DNA from RNA. See also *Bial's test Bial's test is a chemical test for the presence of pentoses originally developed for the diagnosis of pentosuria. It is named after Manfred Bial, a German physician. The components include orcinol, hydrochloric acid, and ferric chloride. A pentos ... References {{reflist Analytical reagents Genetics techniques ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gunshot Residue
Gunshot residue (GSR), also known as cartridge discharge residue (CDR), gunfire residue (GFR), or firearm discharge residue (FDR), consists of all of the particles that are expelled from the muzzle of a gun following the discharge of a bullet. It is principally composed of burnt and unburnt particles from the explosive primer, the propellant (gunpowder), stabilisers and other additives. The act of firing a bullet incites a highly pressurised, explosive reaction that is contained within the barrel of the firearm, which expels the bullet. This can cause the bullet, the barrel, or the cartridge to become damaged, meaning gunshot residue may also include metallic particles from the Cartridge (firearms), cartridge casing, the bullet jacket, as well as any other dirt or residue contained within the barrel that could have become dislodged. Law enforcement commonly use swabbing, adhesives and vacuums with very fine filters to collect GSR. They commonly swab the web of the non-firing han ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aniline
Aniline (From , meaning ' indigo shrub', and ''-ine'' indicating a derived substance) is an organic compound with the formula . Consisting of a phenyl group () attached to an amino group (), aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans. Relative to benzene, aniline is "electron-rich". It thus participates more rapidly in electrophilic aromatic substitution reactions. Likewise, it is also prone to oxidation: while freshly purified aniline is an almost colorless oil, exposure to air results in gradual darkening to yellow or red, due to the formation of strongly colored, oxidized impurities. Ani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenothiazine
Phenothiazine, abbreviated PTZ, is an organic compound that has the formula S(C6H4)2NH and is related to the thiazine-class of heterocyclic compounds. Derivatives of phenothiazine are highly bioactive and have widespread use and rich history. The derivatives chlorpromazine and promethazine revolutionized the fields of psychiatry and allergy treatment, respectively. An earlier derivative, methylene blue, was one of the first antimalarial drugs, and derivatives of phenothiazine are currently under investigation as possible anti-infective drugs. Phenothiazine is a prototypical pharmaceutical lead structure in medicinal chemistry. Uses Phenothiazine itself is only of theoretical interest, but derivatives of it revolutionized psychiatry, other fields of medicine, and pest management. Other derivatives have been studied for possible use in advanced batteries and fuel cells. Phenothiazine-derived drugs In 1876, methylene blue, a derivative of phenothiazine, was synthesized by H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aniline
Aniline (From , meaning ' indigo shrub', and ''-ine'' indicating a derived substance) is an organic compound with the formula . Consisting of a phenyl group () attached to an amino group (), aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans. Relative to benzene, aniline is "electron-rich". It thus participates more rapidly in electrophilic aromatic substitution reactions. Likewise, it is also prone to oxidation: while freshly purified aniline is an almost colorless oil, exposure to air results in gradual darkening to yellow or red, due to the formation of strongly colored, oxidized impurities. Ani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antioxidant
Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants are frequently added to industrial products, such as polymers, fuels, and lubricants, to extend their usable lifetimes. Foods are also treated with antioxidants to prevent Food spoilage, spoilage, in particular the rancidification of Vegetable oil, oils and fats. In Cell (biology), cells, antioxidants such as glutathione, mycothiol, or bacillithiol, and enzyme systems like superoxide dismutase, inhibit damage from oxidative stress. Known diet (nutrition), dietary antioxidants are vitamins vitamin A, A, vitamin C, C, and vitamin E, E, but the term has also been applied to various compounds that exhibit antioxidant properties in vitro, having little evidence for antioxidant properties in vivo. Dietary supplements marketed as antioxidants hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylamine
Triphenylamine is an organic compound with formula (C6H5)3N. In contrast to most amines, triphenylamine is nonbasic. At room temperature it appears as a colorless crystalline solid, with monoclinic structure. It is well miscible in diethyl ether and benzene, but it is practically insoluble in water, and partially in ethanol. Its derivatives have useful properties in electrical conductivity and electroluminescence, and they are used in OLEDs as hole-transporters. Triphenylamine can be prepared by Ullmann arylation of diphenylamine. Chemical properties Triphenylamine has three aromatic groups directly linked to the central nitrogen atom. Each aromatic group acts as an electron attractor, directing the electron cloud of the lone pair of nitrogen towards it. With the delocalization of the nitrogen lone pair, a partial positive charge is conferred to nitrogen, counterbalanced by the partial negative charge localized on the aromatic groups. This arrangement prevents nitrogen protonat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anilinium Chloride
Anilinium chloride is the organic compound with the formula . A white solid, it is the chloride salt of anilinium, which is the conjugate acid of aniline, . Anilinium chloride is produced by treatment of aniline with hydrochloric acid. The cation consists of a phenyl ring attached to a tetrahedral ammonium center. The C-N bond elongates from 1.41 Å in aniline to 1.474 Å in anilinium. Uses Anilinium chloride is used as a precursor to diphenylamine by heating with aniline: : {{chem2, C6H5NH2 + C6H5NH3Cl -> (C6H5)2NH + NH3 + HCl It reacts with formaldehyde Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as ... to give methylenedianiline, a precursor to commercial polymers. References * Anilines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amine
In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of electrons. Amines can also exist as hetero cyclic compounds. Aniline is the simplest aromatic amine, consisting of a benzene ring bonded to an amino group. Amines are classified into three types: primary (1°), secondary (2°), and tertiary (3°) amines. Primary amines (1°) contain one alkyl or aryl substituent and have the general formula RNH2. Secondary amines (2°) have two alkyl or aryl groups attached to the nitrogen atom, with the general formula R2NH. Tertiary amines (3°) contain three substituent groups bonded to the nitrogen atom, and are represented by the formula R3N. The functional group present in primary amines is called the amino group. Classification of amines Amines can be classified according to the nature and number o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
