title: Characteristics and source identification of fine particulate n-alkanes in Beijing, China.
abstract: Ambient particulate n-alkanes were determined for fine particle (PM2.5) samples collected from Sep 2003 to July 2004 in Beijing, China. The average concentration of total n-alkanes (sigma n-alkanes) from C11 to C34 was 425.72 ng/m3, ranged from 7.02 to 2893.28 ng/m3. The concentration distributions of n-alkanes homologues in this study exhibited peaks at C21 and C29 in heating season, and C29 in non-heating season. The average carbon preference index (CPI) value was 1.88 in the range of 1.18-3.88. The maximum CPI in summer indicated the contribution of biogenic origins such as plant wax; while the minimum CPI value in winter was probably a result of fossil fuel combustion. Preliminary estimation from these results showed that 59% of the n-alkanes in PM2.5 in Beijing summer originated from plant wax, while 74%-88% was from fossil fuel combustion in other three seasons. Source estimation was further performed using principal component analysis method. Two major components were yielded accounting for 57.3% and 30.9% of the total variance, which presented the fossil fuel and biogenic contribution, respectively.
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, Department of Environmental Science & Engineering, Tsinghua University, Beijing 100084, China. duanfk@tsinghua.edu.cn
authors.forename: Fengkui
authors.initials: F
authors.lastname: Duan
authors.forename: Kebin
authors.initials: K
authors.lastname: He
authors.forename: Xiande
authors.initials: X
authors.lastname: Liu
mesh_terms: D000473:Alkanes / Q000032:analysis*; D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D052638:Particulate Matter / Q000032:analysis; D025341:Principal Component Analysis
chemical_list: D000473:Alkanes; D052638:Particulate Matter