[Characterization of organic carbon (OC) and elemental carbon (EC) in PM2.5 during the winter in three major cities in Fujian province, China].

Autor: Chen YT; Environmental Science and Engineering Department, College of Chemical Engineering, Huaqiao University, Xiamen 361021, China. ytchen@iue.ac.cn, Chen JS, Hu GR, Xu LL, Yin LQ, Zhang FW
Jazyk: čínština
Zdroj: Huan jing ke xue= Huanjing kexue [Huan Jing Ke Xue] 2013 May; Vol. 34 (5), pp. 1988-94.
Abstrakt: PM2.5 samples were collected in three cities (Fuzhou, Xiamen and Quanzhou) in Fujian Province, China, during the winter, and were analyzed for organic carbon (OC) and elemental carbon (EC) by thermal optical transmission (TOT). The characteristics such as pollution levels and spatial distributions of PM2.5, OC and EC, correlations between OC and EC, OC/EC ratios and secondary organic carbon (SOC) were discussed in details. Average concentrations of PM2.5 were ranged from (79.94 +/- 18.08) microg(-3) to (114.78 +/- 26.10) microg x m(-3), which were in excess of the Ambient Air Quality Standards (GB 3095-2012) 24-hr mass-based standards of 75 microg x m(-3). Averages concentrations of OC and EC were fluctuated from (14.77 +/- 2.65) microg x m(-3) to (19.27 +/- 1.96) microg x m(-3) and (1.99 +/- 0.50) microg x m(-3) to (3.36 +/- 0.41) microg x m(-3), respectively, which were 1.2 to 1.6 times and 1.2 to 2.0 times more than that in the background site, Pingtan in Fuzhou. Correlations between OC and EC in PM2.5 were found to be strong in Pingtan (R2 = 0.70) and Jin'an (R2 = 0.66) (Fuzhou) , suggesting that there were similar primary pollutants of OC and EC. Average OC/EC ratios were 5.64-7.71 and all higher than 2, which indicated that the secondary organic carbon (SOC) was formed. The estimated concentrations of SOC were from 2.47 microg x m3 to 7.17 microg x m(-3), which contributed 13.08%-45.67% to the OC and 2.20%-7.78% to PM2.5.
Databáze: MEDLINE