title: Characteristics and source apportionment of PM1 emissions at a roadside station.
abstract: The mass concentrations of PM(1) (particles less than 1.0 μm in aerodynamic diameter), organic carbon (OC), elemental carbon (EC), water-soluble ions, and up to 25 elements were reported for 24h aerosol samples collected every sixth day at a roadside sampling station in Hong Kong from October 2004 to September 2005. Annual average PM(1) mass concentration was 44.5 ± 19.5 μg m(-3). EC, OM (organic matter, OC × 1.2), and SO(4)(=) were the dominant components, accounting for ∼ 36%, ∼ 26%, and ∼ 24% of PM(1), respectively. Other components, i.e., NO(3)(-), NH(4)(+), geological material, trace elements and unidentified material, comprised the remaining ∼ 14%. Annual average OC/EC ratio (0.6 ± 0.3) was low, indicating that primary vehicle exhaust was the major source of carbonaceous aerosols. The seasonal variations of pollutants were due to gas-particle partitioning processes or a change in air mass rather than secondary aerosol produced locally. Vehicle exhaust, secondary aerosols, and waste incinerator/biomass burning were dominant air pollution sources, accounting for ∼ 38%, ∼ 22% and ∼ 16% of PM(1), respectively. Pollution episodes during summer (May-August) which were frequently accompanied by tropical storms or typhoons were dominated by vehicle emissions. During winter (November-February) pollution episodes coincided with northeasterly monsoons were characterized by secondary aerosols and incinerator/biomass burning emissions.
authors: Department of Environmental Science and Technology, School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, No.28 Xianning West Road, Xi'an, Shaanxi, 710049, China. chengyan@mail.xjtu.edu.cn
authors: Y
authors: Y
authors: Cheng
authors: S C
authors: SC
authors: Zou
authors: S C
authors: SC
authors: Lee
authors: J C
authors: JC
authors: Chow
authors: K F
authors: KF
authors: Ho
authors: J G
authors: JG
authors: Watson
authors: Y M
authors: YM
authors: Han
authors: R J
authors: RJ
authors: Zhang
authors: F
authors: F
authors: Zhang
authors: P S
authors: PS
authors: Yau
authors: Y
authors: Y
authors: Huang
authors: Y
authors: Y
authors: Bai
authors: W J
authors: WJ
authors: Wu
mesh_terms: D000393:Air Pollutants / Q000737:chemistry*; D002980:Climate; D006723:Hong Kong; D008962:Models, Theoretical; D010316:Particle Size; D012995:Solubility; D014186:Transportation
chemical_list: D000393:Air Pollutants