Nighttime aqueous oxidation of fossil fuel emissions is a significant source of atmospheric secondary organic aerosols.However,the underlying mechanism of the aqueous processing remains unclear.Utilizing ultrahigh-res...Nighttime aqueous oxidation of fossil fuel emissions is a significant source of atmospheric secondary organic aerosols.However,the underlying mechanism of the aqueous processing remains unclear.Utilizing ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry of watersoluble organic carbon samples,we present field observations that reveal the aqueous-phase conversion of nitroaromatic compounds(NACs)and sulfur-containing aerosols from fossil fuel combustion at high relative humidity during a severe haze event in Beijing in the winter of 2016.We have confirmed that the ring-breaking oxidation of NACs can generate nitrous acid in the aqueous phase,which rapidly oxidizes sulfur dioxide(SO_(2))to sulfate.Subsequently,reactions between sulfate and unsaturated compounds contribute to the formation of aliphatic organosulfates.Our results elucidate a molecular-level understanding of the aqueous production of sulfur-containing aerosols from NACs and SO_(2) in wintertime urban haze.展开更多
基金supported by the National Natural Science Foundation of China(42130513,42221001,22276099,and U24A20515)the Harvard-NUIST Joint Laboratory on Air Quality and Climate(JLAQC)。
文摘Nighttime aqueous oxidation of fossil fuel emissions is a significant source of atmospheric secondary organic aerosols.However,the underlying mechanism of the aqueous processing remains unclear.Utilizing ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry of watersoluble organic carbon samples,we present field observations that reveal the aqueous-phase conversion of nitroaromatic compounds(NACs)and sulfur-containing aerosols from fossil fuel combustion at high relative humidity during a severe haze event in Beijing in the winter of 2016.We have confirmed that the ring-breaking oxidation of NACs can generate nitrous acid in the aqueous phase,which rapidly oxidizes sulfur dioxide(SO_(2))to sulfate.Subsequently,reactions between sulfate and unsaturated compounds contribute to the formation of aliphatic organosulfates.Our results elucidate a molecular-level understanding of the aqueous production of sulfur-containing aerosols from NACs and SO_(2) in wintertime urban haze.
