Oxidation, inhibition

Rust and oxidation inhibited oils EP lubricants Viscosity (40° o ... 

It is important to recognize that different types of inhibitors often function by different mechanisms, and that a given antioxidant may react in more than one way. Thus, a material that acts as an antioxidant under one set of conditions may become a pro-oxidant in another simation. The search for possible synergistic combinations of antioxidants can be conducted more logically and efficiently if we seek to combine the effects of different modes of action. Five general modes of oxidation inhibition are commonly recognized ... 

Clancy, R.M., Leszczynska-Piziak, J. and Abramason, S.B. (1992). Nitric oxide inhibits neutrophil superoxide anion production via a direct action on the NADPH oxidase. J. Clin. Invest. 90, 1116-1121. 

Takamori, K., Coffee bean oxidation inhibition with sodium sorbate, Jpn. Kokai 77 72,861,1977. (CA16637D)... 

Hogaboam, C.M., Jacobson, K., Collins, S.M. and Blennerhassett, M.G. (1995) The selective beneficial effects of nitric oxide inhibition in experimental colitis. American Journal of Physiology 268, G673—684. 

Abas F, Lajis NH, Israf DA, Khozirah S and Kalsom YU. 2006. Antioxidant and nitric oxide inhibition activities of selected Malay traditional vegetables. Food Chem 95(4) 566-573. 

Hitachi Cable Ltd. (35) has claimed that dehydrogenation catalysts, exemplified by chromium oxide—zinc oxide, iron oxide, zinc oxide, and aluminum oxide—manganese oxide inhibit drip and reduce flammability of a polyolefin mainly flame retarded with ATH or magnesium hydroxide. Proprietary grades of ATH and Mg(OH)2 are on the market which contain small amounts of other metal oxides to increase char, possibly by this mechanism. 

The effect of jumping of the maximal hydroperoxide concentration after the introduction of hydrogen peroxide is caused by the following processes. The cumyl hydroperoxide formed during the cumene oxidation is hydrolyzed slowly to produce phenol. The concentration of phenol increases in time and phenol retards the oxidation. The concentration of hydroperoxide achieves its maximum when the rate of cumene oxidation inhibited by phenol becomes equal to the rate of hydroperoxide decomposition. The lower the rate of oxidation the higher the phenol concentration. Hydrogen peroxide efficiently oxidizes phenol, which was shown in special experiments [8]. Therefore, the introduction of hydrogen peroxide accelerates cumene oxidation and increases the yield of hydroperoxide. 

J Pospisil, PP Klemchuk (eds.), Oxidation Inhibition in Organic Materials, vols 1, 2. Boca Raton, FL CRC Press, 1990. 

Reactions of phenoxyl and aminyl radicals with RH and ROOH are chain propagation steps in oxidation inhibited by phenols and amines (see Chapter 14). Both reactions become important when their rates are close to the initiation rate (see Chapter 14). Mahoney and DaRooge [57] studied the oxidation of 9,10-dihydroanthracene inhibited by different phenols. He went on to estimate the values of rate constants ratio of the reaction of ArO with RH and the reaction In + In (reactions (9) and (10), see Chapter 14) by the kinetic study. The values of kw for the reaction... 

The reaction between the semiquinone radical and dioxygen was found recently in the kinetic study of styrene oxidation inhibited by hydroquinone [102],... 

The formation of the H0S 02 radical was demonstrated by EPR spectroscopy [51]. The homolytic decomposition of hydroperoxide catalyzed by S02 underlies an oscillating pattern of the M-hcxylbenzcne oxidation inhibited by thiophene or BaS04 [48]. Radicals can also be... 

The kinetics of a hydrocarbon mixture (fuel T-6) oxidation inhibited by a powder of Mo and M0S2 was studied by Kovalev et al. [7,9,10], The results of the study of initiated oxidation of T-6 in the presence of Mo and MoS2 are presented in Table 20.1. 

Several mechanisms of fialuridine-induced hepatotoxicity have been suggested fialuridine and its metabolites inhibit mitochondrial DNA replication, leading to decreased mitochondrial DNA and mitochondrial ultrastructural defects [61]. Another mechanism suggested lies in pyruvate oxidation inhibition [62]. 

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