Atmospheric Oxidation and Secondary Particle Formation

With the acceleration of economic development and urbanization, air pollution is becoming increasingly severe in China. The results of a study in 2009 showed that nearly 30% of China’s land area and 500 million people were suffering from haze, especially in the Pan Bohai Sea, the Yangtze River Delta, and the Pearl River Delta. Since the 1970s, China has gradually carried out special research on the acid rain and photochemical smog, revealing that the root cause of these two types of pollution was the regional secondary pollution driven by the atmospheric oxidationAtmospheric oxidation. The monitoring results showed that the atmospheric concentration of nitrogen oxides (NOx), sulfur dioxide (SO2), and PM10 had been decreasing to varying degrees; however, the increase of ozone (O3) concentration and the occurrence of haze had not been effectively suppressed. The main driving force behind the conversion of the primary pollutantsPrimary pollutant into the secondary pollutantsSecondary pollutant is the hydroxyl (OH) radical. However, there is a lack of research on the chemical mechanism of the OH radicalOH radical in complex air pollution currently, which limits our understanding of the causes of secondary pollution.