3C-O2-1650（3P-47） PDF
Single Particle Chemical Composition and Mixing State Observed in Beijing, China during Severe PM2.5 Pollution Periods
Size-resolved single particle chemical composition of atmospheric aerosols during severe PM2.5 pollution periods (October 1-18, 2015) was observed using a single particle mass spectrometer in Beijing, China. The observed 2.6 million atmospheric aerosols with the size range from 100 nm to 2.5 μm were classified into 33 groups based on their chemical composition (similarity in their positive and negative ion mass spectra) using a clustering method. It was found that K-containing aerosols, which were considered being emitted from coal and/or biomass burning processes, were dominant type. The enhanced association of organic composition to the K-containing particles was observed during sever PM2.5 pollution, suggesting the importance of organic composition to the high PM2.5 pollution events.