title: Size distributions of n-alkanes, fatty acids and fatty alcohols in springtime aerosols from New Delhi, India.
abstract: Size-segregated aerosol samples were collected in New Delhi, India from March 6 to April 6, 2012. Homologous series of n-alkanes (C19C33), n-fatty acids (C12C30) and n-alcohols (C16C32) were measured using gas chromatography/mass spectrometry. Results showed a high-variation in the concentrations and size distributions of these chemicals during non-haze, haze, and dust storm days. In general, n-alkanes, n-fatty acids and n-alcohols presented a bimodal distribution, peaking at 0.7-1.1 μm and 4.7-5.8 μm for fine modes and coarse modes, respectively. Overall, the particulate matter mainly existed in the coarse mode (≥2.1 μm), accounting for 64.8-68.5% of total aerosol mass. During the haze period, large-scale biomass burning emitted substantial fine hydrophilic smoke particles into the atmosphere, which leads to relatively larger GMDs (geometric mean diameter) of n-alkanes in the fine mode than those during the dust storms and non-haze periods. Additionally, the springtime dust storms transported a large quantity of coarse particles from surrounding or local areas into the atmosphere, enhancing organic aerosol concentration and inducing a remarkable size shift towards the coarse mode, which are consistent with the larger GMDs of most organic compounds especially in total and coarse modes. Our results suggest that fossil fuel combustion (e.g., vehicular and industrial exhaust), biomass burning, residential cooking, and microbial activities could be the major sources of lipid compounds in the urban atmosphere in New Delhi.
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
authors.forename: Mingjie
authors.initials: M
authors.lastname: Kang
authors.affiliation: 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. Electronic address: fupingqing@mail.iap.ac.cn.
authors.forename: Pingqing
authors.initials: P
authors.lastname: Fu
authors.affiliation: CSIR-National Physical Laboratory, New Delhi 110012, India.
authors.forename: Shankar G
authors.initials: SG
authors.lastname: Aggarwal
authors.affiliation: CSIR-National Physical Laboratory, New Delhi 110012, India.
authors.forename: Sudhanshu
authors.initials: S
authors.lastname: Kumar
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
authors.forename: Yele
authors.initials: Y
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
authors.forename: Zifa
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000336:Aerosols / Q000032:analysis*; D000393:Air Pollutants / Q000032:analysis*; D000473:Alkanes / Q000032:analysis*; D001272:Atmosphere / Q000737:chemistry; D018533:Biomass; D004784:Environmental Monitoring; D005227:Fatty Acids / Q000032:analysis*; D005233:Fatty Alcohols / Q000032:analysis*; D005579:Fossil Fuels; D008401:Gas Chromatography-Mass Spectrometry; D007194:India; D008055:Lipids / Q000032:analysis; D009930:Organic Chemicals / Q000032:analysis; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis; D012906:Smoke / Q000032:analysis; D001335:Vehicle Emissions / Q000032:analysis
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D000473:Alkanes; D005227:Fatty Acids; D005233:Fatty Alcohols; D005579:Fossil Fuels; D008055:Lipids; D009930:Organic Chemicals; D052638:Particulate Matter; D012906:Smoke; D001335:Vehicle Emissions
keywords: Fatty acids; Fatty alcohols; Organic aerosols; Size distribution; n-Alkanes