Nitrogen from oxidation

Oxidation of A-aminoazetidines (19), deoxygenation of A-nitrosoazetidines (20) and direct deamination of azetidines (21) with difluoroamine leads to cyclopropanes (23) by extrusion of nitrogen from a diazine intermediate (22) (63JA97). A further interesting ring contraction occurs in the Ag" catalysed solvolysis of the A-chloroazetidine (24), which appears to involve the intermediate cation (2S) (7ITLI09). 

The gaseous losses of nitrogen from agriculture include a range of oxidized (NO and NjO) as well as reduced (NHj) compounds. These gases form a part of the... 

Emissions of oxidized nitrogen from UK soils, in contrast with those of agricultural NH emission, are much smaller and amount to 20 kt NO-N and... 

Furan [110-00-9] M 68.1, b 31.3°, d 1.42, n 1.4214. Shaken with aqueous 5% KOH, dried with CaS04 or Na2S04, then distd under nitrogen, from KOH or sodium, immediately before use. A trace of hydroquinone could be added as an inhibitor of oxidation. 

Within 6 months after enactment of the Qean Air Act Amendments of 1990, and at least every 3 years thereafter, the Administrator shall review and, if necessary, revise, the methods ( emission factors ) used for purposes of this Act to estimate the quantity of emissions of carbon monoxide, volatile organic compounds, and oxides of nitrogen from sources of such air pollutants (including area sources and mobile sources). In addition, the Administrator shall permit any person to demonstrate improved emissions estimating techniques, and following approval of such techniques, the Administrator shall authorise the use of such techniques. Any such technique may be approved only after appropriate public participation. Until the Administrator has completed the revision required by this section, nothing in this section shall be construed to affect the validity of emission factors established by the Administrator before the date of the enactment of the Clean Air Act Amendments of 1990. 

Viable methods of producing the metals from oxide ores have to siumount two problems. In the first place, reduction with carbon is not possible because of the formation of intractable carbides (p. 299), and even reduction with Na, Ca or Mg is unlikely to remove all the oxygen. In addition, the metals are extremely reactive at high temperatures and, unless prepared in the absence of air, will certainly be contaminated with oxygen and nitrogen. 

The rich gas from the absorption operation is usually stripped of the desirable components and recycled back to the absorber (Figure 8-57). The stripping medium may be steam or a dry or inert gas (methane, nitrogen, carbon oxides—hydrogen, etc.). This depends upon the process application of the various components. 

It is usual to protect carbon from oxidation at high temperature by the use of alternative gas atmospheres — these are generally hydrogen, nitrogen, argon or helium. The first two will react at temperatures above 1700°C to form methane and cyanogen, respectively. 

Atroschenko and Kargin (Ref 26, pp 223-268) describes several methods of prepn of coned nitric acid directly from oxides of nitrogen... 

Step 1 Oxidation of ammonia nitrogen s oxidation number increases from —3 to +2 ... 

Step 3 Disproportionation in water nitrogen s oxidation number changes from +4 to +5 and +2 ... 

The amino acids are required for protein synthesis. Some must be supplied in the diet (the essential amino acids) since they cannot be synthesized in the body. The remainder are nonessential amino acids that are supplied in the diet but can be formed from metabolic intermediates by transamination, using the amino nitrogen from other amino acids. After deamination, amino nitrogen is excreted as urea, and the carbon skeletons that remain after transamination (1) are oxidized to CO2 via the citric acid cycle, (2) form glucose (gluconeogenesis), or (3) form ketone bodies. 

Another example of an irreversible reaction is the removal of oxides of nitrogen from gas streams using hydrogen peroxide ... 

Photochemical elimination reactions include all those photoinduced reactions resulting in the loss of one or more fragments from the excited molecule. Loss of carbon monoxide from type I or a-cleavage of carbonyl compounds has been previously considered in Chapter 3. Other types of photoeliminations, to be discussed here, include loss of molecular nitrogen from azo, diazo, and azido compounds, loss of nitric oxide from organic nitrites, and loss of sulfur dioxide and other miscellaneous species. 

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