RESUMO
The experimental evidence related to the long-range transport and transformations of sulfates has been critically reviewed. It has been concluded that sulfate emissions from various sources can be superimposed on each other during long-range transport to create episodes far from the contributing sources. Sulfates are important contributors to degrading visibility through the United States including relatively pristine areas in the western United States. Acid sulfate components, along with nitric acid, may increase the problem of acidity in precipitation on soils, vegetation, and lakes in certain areas of the eastern United States. Improvements in monitoring of these pollutants are required to follow changes in air quality caused by long-range transport.
Assuntos
Poluentes Atmosféricos , Sulfatos , Carvão Mineral , Estados Unidos , Tempo (Meteorologia)Assuntos
Poluição do Ar/análise , Hidrocarbonetos/análise , Metano/análise , Métodos , Estados UnidosAssuntos
Poluição do Ar/análise , Ritmo Circadiano , Modelos Teóricos , Aerossóis , Amônia , Hidrocarbonetos , Óxido Nítrico , Nitrogênio , Óxido Nitroso , ÓxidosAssuntos
Hidrocarbonetos , Luz , Óxidos , Poluição do Ar , Fenômenos Químicos , Química , NitrogênioAssuntos
Hidrocarbonetos , Luz , Óxidos , Poluição do Ar , Fenômenos Químicos , Química , NitrogênioAssuntos
Poluição do Ar/análise , Fenômenos Químicos , Química , Hidrocarbonetos , Óxido Nítrico , Oxirredução , Ozônio , Estados UnidosRESUMO
A new group of gas-phase reactions have been shown to contribute to the photooxidation of hydrocarbons. The phtotooxidation of aliphatic aldehydes at wavelengths below 3400 angstroms produces intermediates that react with olefinic and aromatic hydrocarbons. Although the photooxidation rates are slower than those induced by nitrogen oxide, the rates are significant, considering the interest in urban atmospheric reactions. These results may indicate that the contro of nitrogen oxides alone may not effectively reduce photochemical air pollution.