Molecular distributions and compound-specific stable carbon isotopic compositions of lipids in wintertime aerosols from Beijing.
Molecular distributions and stable carbon isotopic compositions (δ(13)C) of n-alkanes, fatty acids and n-alcohols were investigated in urban aerosols from Beijing, northern China to better understand the sources and long-range atmospheric transport of terrestrial organic matter during polluted and clear days in winter. n-Alkanes (C19-C36), fatty acids (C8-C32) and n-alcohols (C16-C32) detected in Beijing aerosols are characterized by the predominance of C23, C16 and C28, respectively. Carbon preference index (CPI) values of n-alkanes, the ratios of the sum of odd-numbered n-alkanes to the sum of even-numbered n-alkanes, are close to 1, indicating a heavy influence of fossil fuel combustion. Relatively higher ratios of C(18:0+16:0)/C(18:n+16:1) (fatty acids) on clear days than polluted days indicate that long-distance transport and/or photochemical aging are more significant during clear days. δ(13)C values of n-alkanes and low molecular weight fatty acids (C16:0, C18:0) ranged from -34.1 to -24.7% and -26.9 to -24.6%, respectively, which are generally heavier on polluted days than those on clear days. Such a wide range suggests that atmospheric lipids in Beijing aerosols originate from multiple sources and encounter complicated atmospheric processes during long-range transport in North China.
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.|University of Chinese Academy of Sciences, Beijing 100049, China.
Lujie
L
Ren
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.|Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science &Technology, Nanjing, 210044, China.
Pingqing
P
Fu
Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China.
Yue
Y
He
Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China.
Juzhi
J
Hou
Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
Jing
J
Chen
Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China.
Chandra Mouli
CM
Pavuluri
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
Yele
Y
Sun
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
Zifa
Z
Wang