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Nitrogen-based Oxidants

See Other DICHROMATE SALTS OF NITROGENOUS BASES, OXIDANTS... [Pg.1088]

It is known that preparation of the oxidant salt under anhydrous conditions is explosion-prone [1], but during repetition of a supposedly safe preparative method [2], recommended for large-scale use [3], ignition and a violent explosion occurred. Use of more water to dissolve completely the chromium trioxide, and a reaction temperature below 25°C, are recommended [4], During a study by TGA of the thermal degradation of the salt, too-rapid heating of the samples led to explosions with fire [5]. See other DICHROMATE SALTS OF NITROGENOUS BASES, OXIDANTS... [Pg.1144]

The XeF+ cation forms Lewis acid—base adduct cations containing N—Xe—F linkages with nitrogen bases that are resistant to oxidation by the strongly oxidizing XeF+ cation having an estimated electron affinity of the XeF+ cation of 10.9 eV (12). The thermally unstable colorless salt,... [Pg.24]

Three generations of latices as characterized by the type of surfactant used in manufacture have been defined (53). The first generation includes latices made with conventional (/) anionic surfactants like fatty acid soaps, alkyl carboxylates, alkyl sulfates, and alkyl sulfonates (54) (2) nonionic surfactants like poly(ethylene oxide) or poly(vinyl alcohol) used to improve freeze—thaw and shear stabiUty and (J) cationic surfactants like amines, nitriles, and other nitrogen bases, rarely used because of incompatibiUty problems. Portiand cement latex modifiers are one example where cationic surfactants are used. Anionic surfactants yield smaller particles than nonionic surfactants (55). Often a combination of anionic surfactants or anionic and nonionic surfactants are used to provide improved stabiUty. The stabilizing abiUty of anionic fatty acid soaps diminishes at lower pH as the soaps revert to their acids. First-generation latices also suffer from the presence of soap on the polymer particles at the end of the polymerization. Steam and vacuum stripping methods are often used to remove the soap and unreacted monomer from the final product (56). [Pg.25]

Hydrolysis using aqueous alkaH has been found to remove ash material including pyrite. A small pilot plant for studying this process was built at the BatteUe Memorial Institute in Columbus, Ohio (74) and subsequentiy discontinued. Other studies have produced a variety of gases and organic compounds such as phenols, nitrogen bases, Hquid hydrocarbons, and fatty acids totaling as much as 13 wt % of the coal. The products indicate that oxidation and other reactions as weU as hydrolysis take place. [Pg.224]

Amines are ammonia derivatives in which one or more hydrogen atoms have been replaced by an organic radical. Amines are sometimes called nitrogen bases. Basic chemistries include fatty amines (as primary, secondary, tertiary, and polyamines), amine salts, quaternary ammonium compounds, amine oxides, and amides. [Pg.517]

The reduction electrochemistry of ECP porphyrin films furthermore responds to added axial ligands in the expected ways. We have tested this (2,6) for the ECP form of the iron complex of tetra(o-amino)phenyl)porphyrin by adding chloride and various nitrogeneous bases to the contacting solutions, observing the Fe(III/II) wave shift to expected potentials based on the monomer behavior in solution. This is additional evidence that the essential porphyrin structure is preserved during the oxidation of the monomer and its incorporation into a polymeric film. [Pg.412]

See Other QUATERNARY OXIDANTS, OXOSALTS OF NITROGENOUS BASES... [Pg.1015]

While anodic amide oxidations have found the most synthetic use to date, the oxidation of nitrogen-containing molecules is not limited to amide substrates. A variety of amine oxidations have been studied, and the Kolbe electrolysis of carboxylic acids has been used to generate nitrogen-based reactive intermediates. Many of these reactions also offer unique synthetic advantages (Sects. 10.2 and 10.3). [Pg.280]

This reaction resembles decarboxylation of carboxylates during electrode one-electron oxidation (Kolbe reaction). Kolbe reaction also consists of one-electron oxidation, decarboxylation, and culminates in dimerization of alkyl radicals just after their formation at the electrode surface. When the sulfate radical acts as a one-electron oxidant, the caboradical dimerization is hampered. The radicals can be used in preparative procedures. One typical example is alkylation of heterocyclic nitrogen bases (Minisci et al. 1983). This difference between Kolbe reaction and the reaction with the help of a dissolved electrode (the sulfate radical) deserves some explanation. The concentration of the one-electron oxidation products in the electrode vicinity is significantly higher than that in the bulk of the solution. Therefore, in the case of anode-impelled reactions, the dimerization of radicals produced from carboxylates proceeds easily. Noticeably, 864 secures the single electron nature of oxidation more strictly than an anode. In electrode reactions, radical intermediates can... [Pg.64]

The determination of total nitrogen by oxidative combustion with chemiluminescence detection is based on the following reactions ... [Pg.184]

Nitrogenous bases Lead(lV) oxide, Carbon black. Chlorinated paraffin Manganese(lV) oxide Magnesium, Methanol Mercury(l) azide... [Pg.184]


See other pages where Nitrogen-based Oxidants is mentioned: [Pg.358]    [Pg.224]    [Pg.397]    [Pg.10]    [Pg.351]    [Pg.79]    [Pg.210]    [Pg.358]    [Pg.224]    [Pg.397]    [Pg.10]    [Pg.351]    [Pg.79]    [Pg.210]    [Pg.415]    [Pg.3]    [Pg.299]    [Pg.167]    [Pg.120]    [Pg.309]    [Pg.51]    [Pg.120]    [Pg.1193]    [Pg.1684]    [Pg.151]    [Pg.187]    [Pg.489]    [Pg.97]    [Pg.241]    [Pg.383]    [Pg.281]    [Pg.286]    [Pg.287]    [Pg.285]    [Pg.34]    [Pg.344]    [Pg.379]    [Pg.275]    [Pg.37]   


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Nitrogen bases

Nitrogeneous bases

Nitrogenous bases

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