Characteristics of atmospheric particulate organic carbon (OC) and elemental carbon (EC) in Tianjin, China
In order to investigate the characteristics of carbonaceous aerosol in Tianjin, atmospheric particle samples from urban, suburban and coastal areas of the city were collected between October 2006 and January 2007, and analyzed for EC and OC using thermal optical reflectance (TOR) method. The wintertime 24-hr average concentrations of OC and EC were 44.1 and 3.7 μg·m-3, accounting for 18.0％ and 2.1％ of PM2.5 mass, respectively. The OC dominated the carbonaceous compounds constituting about 90％ of the TC. The high OC and low EC levels were observed in Tianjin compared to those in other urban environments. The OC/EC ratio measured in this study ranged from 2.5 to 22.6 with an average of 9.3, higher than ratios measured in any other urban atmospheres. There was no relationship between photochemical activity indicated by ozone level and secondary organic aerosol production. Fine particle concentrations tended to be higher than the coarse particle with PM2.5 constituting 60.9％ of the PM10 mass. The majority (～77％) of OC and EC were associated with the fine particle mode. Winter heating was found to have a great influence on the concentrations of fine particles and OC. Nearly half of the organic carbon was measured to be water soluble and the content of pyrolyzed organic carbon determined by TOR can be used as a substitute in evaluating the abundance of water-soluble organic carbon (WSOC). The enrichment of OC relative to EC observed in Tianjin atmosphere reflected the combined influences of multiple sources.
Organic carbon Elemental carbon OC/EC ratio TOR Tianjin
Zhipeng Bai Weifang Li Aixia Liu Jingdong Wei
State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prev Meteorological Institute of Tianjin, Tianjin 300074, PR China Environmental Monitoring Station of Dongli District of Tianjin, 300300, China
国际会议
天津
英文
50-57
2007-07-17（万方平台首次上网日期，不代表论文的发表时间）