title: [Pollution Characteristics and Sources of Carbonaceous Aerosol in PM2.5 During Winter in Guanzhong Area].
abstract: To study the characteristics and sources of carbonaceous aerosol in PM2.5 during winter in Guanzhong area, PM2.5 samples were collected from December 2012 to February 2013 in Xi'an, Baoji, Weinan and Qinling, and then organic carbon (OC) and elemental carbon (EC) were analyzed following the thermal/optical reflection protocol. The average concentrations of OC in the four sites were 47.8, 45.8, 31.2 and 37.0 microg x m(-3), respectively, while EC concentrations were 8.5, 6.7, 7.6 and 5.7 microg x m(-3), respectively. Total carbonaceous aerosol (TCA) accounted for 36.4%, 46.2%, 36.9% and 33.4% of PM2.5, respectively. OC was strongly correlated with EC in Xi'an (R2 = 0.93) and Qinling (R2 = 0.91), while weakly correlated in Baoji (R2 = 0.58) and Weinan (R2 = 0.62), which indicated that OC and EC had more similar sources or higher mixing degree in the former two sites. All OC/EC ratios exceeded 2.0, which indicated the formation of secondary organic carbon (SOC). In Xi'an, Baoji, Weinan and Qinling, SOC accounted for 21.6%, 40.3%, 23.2% and 27.8% of OC, respectively. Positive matrix factorization (PMF) was used to analyze the sources of carbonaceous aerosol and four sources were obtained. Coal burning was the major source, contributing 45.3%-47.9% in Guanzhong area. Gasoline vehicle and biomass burning were the minor sources, contributing 26.1%-33.1% and 14.3%-20.1% respectively. In addition, diesel vehicle also had some contribution to carbonaceous aerosol.
authors.forename: Peng-shan
authors.initials: PS
authors.lastname: Tian
authors.forename: Jun-ji
authors.initials: JJ
authors.lastname: Cao
authors.forename: Yong-ming
authors.initials: YM
authors.lastname: Han
authors.forename: Ning-ning
authors.initials: NN
authors.lastname: Zhang
authors.forename: Rong
authors.initials: R
authors.lastname: Zhang
authors.forename: Sui-xin
authors.initials: SX
authors.lastname: Liu
mesh_terms: D000336:Aerosols / Q000032:analysis*; D000393:Air Pollutants / Q000032:analysis*; D018533:Biomass; D002244:Carbon / Q000032:analysis; D002681:China; D003031:Coal; D004784:Environmental Monitoring; D005742:Gasoline; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis*; D012621:Seasons
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D003031:Coal; D005742:Gasoline; D052638:Particulate Matter; D002244:Carbon