Oxidizers nitrites

V-Alkylpipera ines and PIP can react with nitrosating agents such as nitrogen oxides, nitrites or nitrous acid to form nitrosamine derivatives (61,62). Piper a2ine dihydrochloride [142-64-3] reacts with aqueous sodium nitrite and HCl to give the dinitrosamine that melts at 156—158°C (61). 

Nitrobacter, an aerobic bacterium, can materially depress pH by oxidizing nitrite (NO2 ) to nitrate (NOa ), in effect producing nitric acid. Acidity may increase until pH is between 3 and 5. Such bacteria require high concentrations of oxygen and cause problems only in oxygenated systems. 

It has been suggested that N02 might be formed by the oxidation of nitrite by numerous biological oxidants. Thus, Shibata et al. [90] reported that horse radish peroxidase (HRP) + hydrogen peroxide oxidized nitrite by the following mechanism ... 

Miller, D. J., and Nicholas, D. J. D. (1985). Characterization of a soluble cytochrome oxide/nitrite reductase from Nitrosomoruis europaea. J. Gen. Microbiol. 131, 2851-... 

A mixture of potassium nitrite and potassium nitrate is treated with nitric acid to oxidize nitrite to nitrate ... 

These include nitrite and trimethylammonium oxide. Nitrite undergoes a six-electron reduction to give ammonia in a reaction catalyzed by a nitrite reductase. Nitrite reductase activity with lactate and formate has been reported, although other donors may support the reduction of nitrite. It should be noted that at least three pathways in E. coli exist for the reduction of nitrite. 

The other genus (i.e., Nitrobacter sp.) of bacteria oxidizes nitrite to nitrate as follows ... 

Nitric oxide Pd/C (500 min) Not reported nitrous oxide nitrite 8... 

The modified electrodes were investigated for catalysis of nitrite electrooxidation in pH 7.4 phosphate buffer solution. Nitrite disproportionation to nitric oxide (NO) is insignificant at this pH and thus the catalysis monitored is that of nitrite oxidation. Nitrite oxidation occurred at 0.71 V on the SAM of Mn5b [76], at 0.63 V on polymerized OTiPc (NH2)4 [45], and at 0.65 V on polymerized MnPc (NH2)4... 

Tropylium ion is a weak oxidant, and it is interesting to ponder on why it does not oxidize nitrite ion, in principle a feasible electron-transfer step (entry no. 19). 

Gladwin, M.T., Crawford, J.H., and Ratel, R.R. 2004. The biochemistry of nitric oxide, nitrite and hemoglobin Role in blood flow regulation. Free Radical Biology Medicine, 36 707-17. 

Nitrification seems limited to a number of autotrophic bacteria. The dominant genus that is capable of oxidizing ammonia to nitrite in soils is Nitmsomonas, and the dominant genus capable of oxidizing nitrite to nitrate is Nitrobacter. Normally, the two processes are closely connected and nitrite accumulation does not occur. Nitrifying bacteria are chemolithotrophs that utilize the energy derived from nitrification to assimilate C02. 

Decomposition occurs to the same extent for pathways (272) and (273), whereas path (273) is of very minor importance. No peroxonitrite is formed in a cage-recombination reaction of the products of (271). The oxygen anion of (271) reacts further with water to form hydroxyl radicals that can oxidize nitrite anions back to NO2. 

DOT CLASSIFICATION 5.1 Label Oxidizer SAFETY PROFILE A powerftil oxidizer. Nitrites have been implicated as possible carcinogens. When heated to decomposition it emits toxic fumes of NOx, K2O, and Na20. See also POTASSIUM NITRATE and SODIUM NITRITE. 

In alkaline solution, hypochlorite oxidizes nitrite to nitrate with the rate expression (10) and stochiometric reaction (11). 

Nitrification is the aerobic process by which microorganisms oxidize ammonium to nitrate and derive energy. It is the combination of two bacterial processes one group of organisms oxidizes ammonia to nitrite (e.g., Nitrosomonas), after which a different group oxidizes nitrite to... 

Azo Compounds, Azirines, Diazirines, Diazo Compounds, Diazonium Salts, Azides,. V-Oxides, Nitrite Esters and Heteroaromatic Compounds Photofragmentation and Photorearrangement... 

The bacteria grow by oxidizing nitrite (NOD to nitrate (N03 ) (Fig. 1.8). Nitro-bacter winogradskyi is a typical species in this group. In addition to this, Nitrobac-ter hamburgensis, Nitrospina gracilis, Nitrococcus mobilis and others are known... 

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