Search results
Results from the WOW.Com Content Network
Nitric oxide (nitrogen oxide or nitrogen monoxide [1]) is a colorless gas with the formula NO. It is one of the principal oxides of nitrogen . Nitric oxide is a free radical : it has an unpaired electron , which is sometimes denoted by a dot in its chemical formula ( • N=O or • NO).
Nitrogen oxide may refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds: Charge-neutral. Nitric oxide (NO), nitrogen(II) oxide, or ...
Among these are nitric oxide (NO), nitrous oxide (N 2 O), and nitrogen dioxide (NO 2), all of which are covered in the NAAQS. NO 2 is the oxide measured and used as the indicator for the entire NO x family as it is of the most concern due to its quick formation and contribution to the formation of harmful ground level ozone. [18]
Nitrogen oxides are released during manufacturing of nitrogen fertilizers. Though nitrous oxide is emitted during its application, it is then reacted in atmosphere to form nitrogen oxides. This third source is attributed to the reaction of atmospheric nitrogen, N 2, with radicals such as C, CH, and CH 2 fragments derived from fuel, [26] rather ...
Nitrogen dioxide tropospheric column density in 2011. Nitrogen dioxide typically arises via the oxidation of nitric oxide by oxygen in air (e.g. as result of corona discharge): [15] 2 NO + O 2 → 2 NO 2. NO 2 is introduced into the environment by natural causes, including entry from the stratosphere, bacterial respiration, volcanos, and lightning.
Schematic drawing, causes and effects of air pollution: (1) greenhouse effect, (2) particulate contamination, (3) increased UV radiation, (4) acid rain, (5) increased ground-level ozone concentration, (6) increased levels of nitrogen oxides. An air pollutant is a material in the air that can have many effects on humans and the ecosystem. [95]
Air pollution is caused by many things. In urban environments, it can contain many components, notably solid and liquid particulates (such as soot from engines and fly ash escaping from incinerators), and numerous different gases (most commonly sulfur dioxide, nitrogen oxides, and carbon monoxide, all related to fuel combustion).
The early standards mainly concerned carbon monoxide (CO) and hydrocarbons (HC). Regulations on nitrogen oxide emissions (NO x) were introduced in the United States, Japan, and Canada in 1973 and 1974, with Sweden following in 1976 and the European Economic Community in 1977. These standards gradually grew more and more stringent but have never ...