Oxidation accelerant

XU z, HUA N, GODBER s (2001) Antioxidant activity of tocopherols, tocotrienols, and y-oryzanol components from rice bran against cholesterol oxidation accelerated by 2, 2 -azobis(2-methylpropionamidine) dihydrochloride. J Agri Food Chem, 49 2077-81. 

Li, Q., Li, Y.W., Wu, P., Xie, R., and Shang, J.K. (2008) Palladium oxide nanoparticles on nitrogen-doped titanium oxide accelerated photocatalytic disinfection and post-illumination catalytic memory . Advanced Materials, 20 (19), 3717-3723. 

HOCl-mediated protein oxidation accelerates under pathophysiological conditions. Thus, proteins from extracellular matrix obtained from advanced human atherosclerotic lesions contained the enhanced levels of oxidized amino acids (DOPA and dityrosine) compared to healthy arterial tissue [44], It was also found that superoxide enhanced the prooxidant effect of hypochlorite in protein oxidation supposedly by the decomposition of chloramines and chlor-amides forming nitrogen-centered free radicals and increasing protein fragmentation [45], In addition to chlorination, hypochlorite is able to oxidize proteins. The most readily oxidized amino acid residue of protein is methionine. Methionine is reversibly oxidized by many oxidants including hypochlorite to methionine sulfide and irreversibly to methionine sulfone [46] ... 

The addition of a small amount of nitric acid vapor or nitric oxide accelerates the process. Invented by J. Hargreaves and T. Robinson in Widnes in 1870, in order to provide sodium sulfate for the Leblanc process, circumventing the need for the sulfuric acid used in the salt-cake section of that process. Reportedly still in use in 1984. 

Phenylephrine (27) is a low-potency sympathomimetic amine used as a decongestant. Solutions become coloured due to an auto-oxidation accelerated by light. In a series of experiments, aqueous solutions of the hydrochloride were left under a UV lamp until a tan colour developed. HPLC analysis showed four main products of which one was identified as adrenaline (19). Even after prolonged irradiation, there was never more than 2% adrenaline in the solution. It was assumed that the catecholamine was removed as it formed by further reaction to adrenochrome and melanine, which accounted for the colour [34],... 

Crafts and Reiber (2) suggested that oxidation, accelerated by light, may account for the increased toxicity of stored isoparaflhiic oils. Although the oxidation products formed are not known, they appear to be primarily organic acids. 

Another property of the iron-defective molybdate is the presence of Mo=0 double bonds on the surface. The hydrogen-abstracting capacity of the catalyst is closely related to Mo6 contained in the Mo=0 as is shown in Sect. 3. There the role of iron is also discussed. It is, however, interesting to note here that pure iron oxides accelerate combustion and that a W03—Fe2(W04)3 catalyst is practically inactive [254], Replacement of iron by chromium is possible but leads to a lower activity [253]. Baussart et al. [46] prepared stoichiometric NiMo04 which showed selective behaviour towards formaldehyde in a pulsed column below 375°C. 

The location of the oxidation front, taken as the average of the two oxidation fronts caused by initiating the sample in the middle of the PP film, was then plotted versus time. The resulting curve shows that the spreading of oxidation accelerates with time (see Fig. 8). It has been reported that the volatile species produced during oxidation of PP can contribute to the spreading of oxidation in-between different samples of PP [139, 140]. A device was constructed that enabled the air flow to be directed over the oxidising... 

Research on the important, and difficult, problem of removing small quantities of carbon monoxide from the air has shown that this can be best effected, by catalytic oxidation at room temperature, by mixtures of oxides, which are far more effective than any of the oxides singly.2 While neither manganese dioxide, silver oxide, nor copper oxide will oxidize carbon monoxide rapidly at room temperature, mixtures of manganese dioxide and copper oxide (60/40) will do so silver oxide also much accelerates the oxidation by manganese dioxide. It is stated that 1 per cent, of potash is beneficial, but larger amounts retard the oxidation. Not all oxides accelerate thus cobalt oxide retards oxidation. Various mixtures of manganese dioxide and other oxides as promoters are sold as Hopcalite. ... 

Then, since, at the end of the induction period, [POOH] is sufficiently close to its steady state value [POOH] obtained in the case of pure thermal oxidation, oxidation accelerates sharply and the end life criterion is rapidly reached. As a result, it has been considered that embrittlement occurs for a critical hydroperoxyde concentration [POOH]p such as ... 

It is important to pay attention to the potential role of peroxides created on the surface of plasma-treated, including plasma polymer-coated, TPOs in the formation of durable bonds between the substrate and primer. It has been known for decades that the peroxides formed on the irradiated polymers (by y-ray. X-ray, electron beams, etc.) can be utilized in graft copolymerization of various monomers. This method is known as the peroxide method of radiation copolymerization [27]. The trunk polymer is first irradiated by ionizing radiation in a vacuum or in an inert gas environment. The irradiated polymer is exposed to air or oxygen to convert free radicals to peroxides. Thus created peroxides-containing polymers were used as the initiator of the free radical polymerization of the second monomer. The polymer peroxides are decomposed by heat or by the use of reduction/oxidation accelerator, i.e., peroxides are converted to free radicals. 

The presence of small amounts of mineral acids, such as sulfuric acid or certain metal oxides, such as zinc or magnesium oxide, accelerates the sphtting reaction. These metal oxides are hue catalysts. They also assist in the formation of emulsions. 

Rates were followed manometrically in a carbon coated reaction vessel added propene and isobutene had no effect on rates although nitric oxide accelerated the reaction a linear dependence of the carbon monoxide formation on the initial pressure was interpreted in terms of a unimolecular decomposition of the dimer. 

Liquid Dosage Forms. In dry form and at very low moisture content, L-ascorbic acid is very stable, but in solution exposed to air or oxygen it is subject to oxidation accelerated by dissolved trace minerals (copper and iron) and light exposure, l-Ascorbic acid is a reducing agent and is subject to oxidative decomposition in solution. This proceeds first to dehydroascorbic acid, which has full vitamin C activity, but continues to diketogulonic acid and various other breakdown products. The degradation reactions are complex and vary with aerobic or anaerobic... 

Phosgene is a common impurity in liquid trichloromethane (chloroform) and arises from aerial oxidation, accelerated by exposure to sunlight [134], Indeed, oxidation occurs neither by air in the absence of sunlight nor by light in the absence of air. 

Cuprous oxide accelerates the substitution reaction, and, for instance, chlorobenzene under these conditions affords a 92% yield of phenol in 1 h at 316 °C. Copper and barium chlorides catalyse also the steam hydrolysis of chlorobenzene over silica gel . 

Alcohols (1° and 2°) are oxidized to carbonyl-containing substances, the creation of a ketone from a secondary alcohol being typical. The oxidation, accelerated in alkaline solutions, involves a hypochlorite intermediate. 

Hypertension accelerates atherosclerosis and stimulates left ventricular and vascular hypertrophy. These pathologic changes are thought to be secondary to both a chronic pressure overload and a variety of nonhemodynamic stimuli. Some of the nonhemodynamic disturbances that have been implicated in these effects include the adrenergic system, RAAS, increased synthesis and secretion of en-dothelin I, and a decreased production of prostacyclin and nitric oxide. Accelerated atherogenesis in hypertension is accompanied by proliferation of smooth muscle cells, lipid infiltration into the vascular endothelium, and an enhancement of vascular calcium accumulation. 

Consequently, as Mn oxides precipitate, oxidation accelerates in response to the increased surface available for selective adsorption of Mn. ... 

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