By Oxidative Processes

Ozonolysis of 2-vinylpyrazine in methanol formed 2-formylpyrazine (732) and oxidation of 2-amino-3-hydroxymethylpyrazine with manganese dioxide in chloroform at room temperature gave 2-amino-3-formylpyrazine (1075). 

The optimum conditions of the oxidation of 2-methylpyrazine to 2-formylpyrazine in the presence of V2O5-M0O3 (V Mo = 1 1) catalyst was 400° with a contact time of 0.1 seconds (1444), and with water vapor and an inert gas (1445). 

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By oxidation processes, for example oxidation of hydrocarbons, fatty acids and even some metals. 

Microbial leaching of metals from ores is a promising adjunct to more aggressive metal recovery technologies (77), but is generally achieved by oxidative processes that generate very acidic waters. It seems unlikely that similar approaches will be of much value in removing contaminant metals and metalloids from soils. 

The conversion of chemical energy by oxidative processes at high temperatures is a major source of heat for many industrial processes and, on a more sophisticated plane, for the propulsion of aircraft and advanced rockets, such as the Shuttle. The generation of high temperatures by these reactions... 

Because of their higher oxidation level with respect to both amides and nitrones, hydroxamic acids have been sought from either by oxidative processes. 

Sweetening of petroleum products implies the removal of dissolved free sulfur and its compounds like hydrogen sulfide, and mercaptans in order that the product has no bad odour and does not tend to cause corrosion. The removal of these is accomplished by oxidation processes, solvent processes or catalytic desulfurization processes. 

Scheme 3) <05TL2189>. However, in this case the reaction did not afford the expected DA adduct, the product being the porphyrin derivative 10 resulting from the tetradehydrogenation of the corresponding adduct. The porphyrin derivative 11 was also obtained although in minor amount this product must result from a cyclization reaction between the beta-fused quinoxaline ring and the adjacent maso-aryl group. Also, bisadducts 12 and 13 were isolated these are the result of site specific bisaddition to opposite pyrrolic rings followed by oxidative processes.

The modification of amino acids in proteins and peptides by oxidative processes plays a major role in the development of disease and in aging (Halliwell and Gutteridge, 1989, 1990 Kim et al., 1985 Tabor and Richardson, 1987 Stadtman, 1992). Tissue damage through free radical oxidation is known to cause various cancers, neurological degenerative conditions, pulmonary problems, inflammation, cardiovascular disease, and a host of other problems. Oxidation of protein structures can alter activity, inhibit normal protein interactions, modify amino acid side chains, cleave peptide bonds, and even cause crosslinks to form between proteins. 

In 1961, Ashby reported the weak light emission produced from several polymers such as nylon, when heated [90], The phenomenon was termed oxylum-inescence because it was caused by oxidative processes and required the presence... 

Electrochemiluminescence Emission occurring in solution, from an electronically excited state produced by high-energy electron transfer reactions Electrogenerated chemiluminescence Emission produced at an electrode surface Oxyluminescence Emission from polymers caused by oxidative processes (presence of oxygen is required)... 

Adipic acid is prepared commercially by oxidative processes using either benzene or phenol as the raw material base. Since both benzene and phenol prices track with the price of crude oil, future adipic acid price will increase as the oil reserve decreases(j ). Thus, there is a need for a new process to produce adipic acid from cheap, and readily available, raw materials such as butadiene, synthesis gas, and methanol. 

The saturated VLCFA and branched-chain fatty acids are stable compounds they are not likely to be destroyed by oxidative processes. In this respect, storage of samples does not require more precautions than freezing. 

The study of photolysis of PBBs in the aqueous phase is more relevant to natural environmental situations than photolysis in proton-donating organic solvents. It was suggested that the photolysis of PBBs in aqueous solution would proceed by oxidative process of photohydroxylation, leading to the formation of phenolic compounds (Norris et al. 1973). However, photolysis of 2,4-dibromo-and 2,3, 4, 5-tetrahromobiphenyl in acetonitrile-water solution showed that debromination was the major reaction (Ruzo et al. 1976). No evidence of the formation of hydroxylated species (phenolic products) was found (Ruzo et al. 1976). 

Methane Conversion by Oxidative Processes Fundamental and Engineering Aspects, E. E. Wolf, ed., Van Nostrand Reinhold, New York, 1992. 

The low carbon content of humic acids isolated from rotted straw and chernozem may be caused not only by oxidizing processes but also by the... 

Catabolism involves pathways composed of enzymes and chemical intermediates that are involved primarily in the breakdown of large molecules into small molecules, often by oxidation processes. Anabolism is the collection of the enzymes and chemical intermediates involved in the biological synthesis of larger molecules from smaller molecules. Anabolism often involves reduction processes. 

Furan-2,5-dicarboxylic add also has tremendous industrial potential, because it could replace oil-derived diadds such as adipic or terephthalic acid as monomers for polyesters and polyamides [98, 99]. This diadd can be synthesized by Pt-catalyzed oxidation with 02 of 5-hydroxymethylfurfural the latter is obtained by acid-catalyzed dehydration of D-frudose or frudosans (inulin) the latter, however, are too expensive as starting materials, and yields from glucose-based waste raw materials are no higher than 40%. Therefore, the potential attractive option of furan-2,5-dicarboxylic acid will develop only after an effident generation of 5-hydroxymethylfurfural from forestry waste materials has been developed. The same compound is also the starting material for the synthesis of other interesting chemicals obtained by oxidative processes, such as 5-hydroxymethylfuroic add, 5-formylfuran-2-carboxylic add and the 1,6-dialdehyde. 

Several processes are available for the production of the additional hydrogen that is necessary for the various heavy feedstock hydroprocessing sequences that have been outlined elsewhere (Chapters 7 and 9), and it is the purpose of the present section to present a general description of these processes. In general, most of the external hydrogen is manufactured by steam-methane reforming or by oxidation processes. Other processes such as ammonia dissociation, steam-... 

Autotrophic Refers to organisms that produce their own organic constituents from inorganic compounds using sunlight for energy or by oxidation process. 

Antioxidant Agent that inhibits oxidation and thus is used to prevent deterioration of preparations by oxidative process Ascorbic acid, ascorbyl palmitate, butylated hydroxyanisole, butylated hydroxytoluene, hypophosphorus acid, monothioglycerol, propyl gallate, sodium ascorbate, sodium bisulfite, sodium formaldehyde, sulfoxylate, sodium metabisulfite... 

Tauber, M.M., Gubitz, G.M., and Rehorek, A.Degradation of azo dyes by oxidative processes laccase and ultrasound trealmenL Biores. Technol. 2008, 99,4213-4220. 

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