A Nitrogen oxides (NOx) is Compounds of nitrogen (N) and oxygen (O) in ambient air; i.e., nitric oxide (NO) and others with a higher oxidation state of N, of which NO2 is the most important toxicologically.
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A nitrogen oxides (NOx) is any inorganic compound containing both nitrogen and oxygen. These compounds act as precursors to other pollutants such as nitrate and ozone. NOx includes nitric oxide (NO), nitrogen dioxide (NO2), and others. NOx are formed by natural processes such as lightning, forest fires, and microbial processes. Anthropogenic sources include agricultural fertilizers and combustion engines. Man-made sources currently equal natural sources (see Schlesinger, 1997).
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A Nitrogen Oxides (NOx) is Gases consisting of one molecule of nitrogen and varying numbers of oxygen molecules. Nitrogen oxides are produced, for example, by the Combustion of fossil fuels in vehicles and electric power plants. In the atmosphere, nitrogen oxides can contribute to formation of photochemical ozone (smog), impair visibility, and have health consequences; they are considered pollutants.