title: [Reconstructed ambient light extinction coefficient and its contribution factors in Beijing in January, 2010].
abstract: Aerosol samples for PM2.5 were collected from 1st January to 31st January 2010, in Beijing. The concentrations of organic carbon, elemental carbon, water-solubile ions and soil elements of all particle samples were determined by thermal/optical carbon analyzer, ion chromatography and X-ray fluorescence spectrometer, respectively. The scattering coefficients (b(sp)), absorbing coefficients (b(ap)) and meteorological parameters for this period were also measured. Ambient light extinction coefficients were reconstructed by IMPROVE formula and were compared with measured light extinction coefficients. The results showed that the average mass concentration of PM2.5 was (144.3 +/- 89.1) microg x m(-3) during campaigning period. The average values of measured b(ap), b(sp) and extinction coefficient (b(ext)) were (67.4 +/- 54.3), (328.5 +/- 353.8) and (395.9 +/- 405.2) Mm(-1), respectively. IMPROVE formula is suitable for source apportionment of light extinction coefficient in campaign period. The average value of calculated b'(ext) was (611 +/- 503) Mm(-1) in January, 2010. The major contributors to ambient light extinction coefficients included (NH4) 2SO4 (24.6%), NH4NO3 (11.6%), OM (45.5%), EC (11.9%) and FS (6.4%), respectively.
authors.affiliation: South China Institute of Environmental Sciences, MEP, Guangzhou 510655, China. zhulihua@scies.org
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Zhu
authors.forename: Jun
authors.initials: J
authors.lastname: Tao
authors.forename: Zhong-Ming
authors.initials: ZM
authors.lastname: Chen
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhao
authors.forename: Ren-Jian
authors.initials: RJ
authors.lastname: Zhang
authors.forename: Jun-Ji
authors.initials: JJ
authors.lastname: Cao
mesh_terms: D000336:Aerosols / Q000032:analysis; D000393:Air Pollutants / Q000032:analysis*; D000645:Ammonium Sulfate / Q000032:analysis; D002244:Carbon / Q000032:analysis; D002681:China; D002947:Cities; D004784:Environmental Monitoring; D008027:Light; D009566:Nitrates / Q000032:analysis; D055095:Optics and Photonics; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis*
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D009566:Nitrates; D052638:Particulate Matter; D002244:Carbon; D000645:Ammonium Sulfate; C006568:ammonium nitrate