Nitrogen compounds, atmosphere

Moore, H. (1974). Isotopic measurements of atmospheric nitrogen compounds. Tellus 26(1-2), 169-174. 

Aneja, V.P., G.C. Murray, and J. Southerland, Atmospheric nitrogen compounds Emissions, transport, deposition,... 

The use of artificial fertilizers in agriculture also generates atmospheric nitrogen compounds that can reach the stratosphere and possible destroy ozone. 

Nitrogen, N2, is a colorless, odorless, tasteless gas that makes up about 75% by mass and 78% by volume of the atmosphere. Nitrogen compounds form only a minor portion of the earth s crust, but all living matter contains nitrogen. The primary natural inorganic deposits of nitrogen are very localized. They consist mostly of KNO3 and NaNOj. Most sodium nitrate is mined in Chile. 

Aneja VP, Roelle pa, Murray GC, Southeeiand J, Eeisman JW, Fowler D, Asman WAH and Patni N (2001) Atmospheric nitrogen compounds II emissions, transport, transformation, deposition and assessment. Atmos Environ 35 1903-1911. 

Figure 1 gives the sum of all sources and sinks for the key atmospheric nitrogen compounds, as well as the contribution from human activities. While it must be recognized that the values given in Fig. 1 have significant uncertainties (in some cases, as much as 50%), the broad picture of the... 

TABLE I Mixing Ratios and Burdens of Atmospheric Nitrogen Compounds... 

The purity of commercial-grade calcium depends to a large extent on the purity of the calcium oxide used in its production. Impurities such as magnesium oxide, or other alkaline-earth or alkaH metal compounds are reduced along with the calcium oxide, and these metals can contaminate the calcium. In addition, small amounts of aluminum may distill with the calcium vapor, and small amounts of calcium nitride may be produced by reaction with atmospheric nitrogen. 

The principal components of atmospheric chemical processes are hydrocarbons, oxides of nitrogen, oxides of sulfur, oxygenated hydrocarbons, ozone, and free radical intermediates. Solar radiation plays a crucial role in the generation of free radicals, whereas water vapor and temperature can influence particular chemical pathways. Table 12-4 lists a few of the components of each of these classes. Although more extensive tabulations may be found in "Atmospheric Chemical Compounds" (8), those listed in... 

Nitrogen fixation Conversion of atmospheric nitrogen into organic nitrogen compounds available to green plants a process that can be carried out only by certain strains of soil bacteria. 

Excess fertilizer and combustion processes also can increase nitrous oxide (NnO) and nitrogen oxides (NOx) in the atmosphere. Nitrous oxide is a powerful greenhouse gas, and nitrogen oxides lead to smog and acid rain. The production of fertilizers requires a great deal of energy. The use of fossil fuels to supply the thermal requirements for fertilizer production further increases emission of nitrogen compounds to the atmosphere. 

Nitrogen compounds These also arise from both natural and synthetic sources. Thus ammonia is formed in the atmosphere during electrical storms, but increases in the ammonium ion concentration in rainfall over Europe in recent years are attributed to increased use of artiflcial fertilisers. Ammonium compounds in solution may increase the wettability of a metaland the action of ammonia and its compounds in causing season cracking , a type of stress-corrosion cracking of cold-worked brass, is well documented. 

Sometimes, knowing only the magnitude of the equilibrium constant, it is possible to decide on the feasibility of a reaction. Consider, for example, a possible method for fixing atmospheric nitrogen—converting it to a compound—by reaction with oxygen ... 

The most important step in the process for the conversion of atmospheric nitrogen into important commercial compounds such as fertilizers and explosives involves the combination of one volume of nitrogen gas with three volumes of hydrogen gas to form two volumes of ammonia gas. 

Prior to World War I the principal sources of nitrogen compounds were some nitrate deposits in Chile. Fritz Haber, a German chemist, successfully developed the process we have just described, thus allowing chemists to use the almost unlimited supply of nitrogen in the atmosphere as a source of nitrogen compounds. 

Moreover, the lipo-chitooligosaccharides, also known as nod factors, permit nitrogen fixation by which plants and symbiotic Rhizobia bacteria can reduce atmospheric nitrogen to the ammonia that is utihzed by the plant, thus making available nitrogen compounds to other living organisms. 

Table 7-9 Atmospheric nitrogen-containing organic compounds...

One reason soils form is because of the endless migration of ions, molecules, and particles into the soil from meteoric inputs. Examples of meteoric inputs include H2O, CO2, O2, nitrogenous compounds, pollutants, salts, and dust. These molecules and compounds come from space, from the atmosphere and the oceans, and from other terrestrial systems. 

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