Identification of secondary organic aerosols based on aerosol mass spectrometry  

作　　者：HUANG XiaoFeng 1,ZHAO QianBiao 1,2,HE LingYan 1,HU Min 2,BIAN QiJing 3,XUE Lian 1 & ZHANG YuanHang 2 1 Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy,Peking University Shenzhen Graduate School,Shenzhen 518055,China 2 State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China 3 Division of Environment,Hong Kong University of Science & Technology,Hong Kong,China 

出　　处：《Science China Chemistry》2010年第12期2593-2599,共7页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(40805049 & 20777001);Science and Technology Plan Project of Shenzhen Municipality(CXB200903090046A);Open Fund of State Key Joint Laboratory of Environmental Simulation and Pollution Control,Peking University

摘　　要：Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so far.Due to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol study.This study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) analysis.Major sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer measurement.It showed that in the winter of Shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±21.8% of the total organic mass.Compared with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary pollutants.The ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2),indicating SOA formation was significantly controlled by activity of photochemistry in the atmosphere.The most effective period for SOA formation was from 9 am～3 pm since the SOA/BC ratio increased by 122% during this period.This study provides a new technical method and a new idea for SOA investigation.Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so far.Due to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol study.This study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) analysis.Major sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer measurement.It showed that in the winter of Shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±21.8% of the total organic mass.Compared with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary pollutants.The ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2),indicating SOA formation was significantly controlled by activity of photochemistry in the atmosphere.The most effective period for SOA formation was from 9 am～3 pm since the SOA/BC ratio increased by 122% during this period.This study provides a new technical method and a new idea for SOA investigation.

关 键 词：SECONDARY organic AEROSOL AEROSOL mass SPECTROMETRY POSITIVE matrix FACTORIZATION (PMF) 

分 类 号：X831[环境科学与工程—环境工程]