Size distribution characteristics of elemental carbon emitted from   Chinese vehicles: Results of a tunnel study and atmospheric implications

doi:10.1021/es0607281

CORC > 北京大学 > 环境科学与工程学院

	Size distribution characteristics of elemental carbon emitted from Chinese vehicles: Results of a tunnel study and atmospheric implications
	Huang, Xiao-Feng ; Yu, Jian Zhen ; He, Ling-Yan ; Hu, Min
刊名	environmental science technology
	2006
关键词	DIESEL SOOT PARTICLES POLYCYCLIC AROMATIC-HYDROCARBONS FINE PARTICULATE MATTER ON-ROAD VEHICLES CHEMICAL-COMPOSITION AIR-QUALITY HONG-KONG AEROSOL EXHAUST URBAN
DOI	10.1021/es0607281
英文摘要	The size distribution characteristics of elemental carbon (EC) emissions from Chinese vehicles have not been previously described. In this study, we collected size-segregated aerosol samples using a 10-stage MOUDI sampler (0.056-18 mu m) in the Zhujiang tunnel, a roadway tunnel in the urban area of Guangzhou, China. The samples were analyzed for EC, organic carbon (OC), and inorganic ions. Fine particles had an OC/EC ratio of 0.57, indicating a dominant contribution of EC from diesel vehicles. Both EC and OC showed a dominant accumulation mode with a mass median aerodynamic diameter (MMAD) of 0.42 Am. In comparison, studies available in the literature typically reported a much lower MMAD for EC (similar to 0.1 mu m) in vehicular emissions in North America. A theoretical analysis indicated that the larger EC particles observed in this study could not have resulted from after-emission growth processes (i.e., water accretion, coagulation, and vapor condensation). This leaves operating conditions such as high engine loads and low combustion efficiencies, which are more prevalent in diesel-fueled Chinese vehicles, as a more plausible inherent reason for producing the larger EC agglomerates. While fresh 0.1 mu m EC particles are unlikely to act as cloud condensation nuclei (CCN), calculations showed that EC particles as large as 0.42 mu m are effective CCN at atmospherically relevant critical supersaturation values of less than 1%. As a result, fresh EC particles from Chinese vehicle emissions could readily undergo cloud processing and form internal mixtures with sulfate in the residue droplet mode particles. This prediction is consistent with observations that EC frequently showed a dominant droplet mode in urban atmospheres in this region. The internal mixing of EC with highly hygroscopic sulfate would facilitate its removal by wet deposition and shorten its lifetime in the atmosphere. In addition, the light-absorbing capabilities of EC particles could also be enhanced due to their internal mixing with sulfate. Numerical aerosol models need to take these factors into consideration for better predictions of the behaviors and effects of urban aerosols in China.; http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000240130200034&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701 ; Engineering, Environmental; Environmental Sciences; SCI(E); EI; 43; ARTICLE; 17; 5355-5360; 40
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/251621]
专题	环境科学与工程学院
推荐引用方式 GB/T 7714	Huang, Xiao-Feng,Yu, Jian Zhen,He, Ling-Yan,et al. Size distribution characteristics of elemental carbon emitted from Chinese vehicles: Results of a tunnel study and atmospheric implications[J]. environmental science technology,2006.
APA	Huang, Xiao-Feng,Yu, Jian Zhen,He, Ling-Yan,&Hu, Min.(2006).Size distribution characteristics of elemental carbon emitted from Chinese vehicles: Results of a tunnel study and atmospheric implications.environmental science technology.
MLA	Huang, Xiao-Feng,et al."Size distribution characteristics of elemental carbon emitted from Chinese vehicles: Results of a tunnel study and atmospheric implications".environmental science technology (2006).