北京清华园采暖前与采暖期PM_(10)中含碳组分的理化特征

The Physical and Chemical Characteristics of Carbonaceous Matter in PM_(10) Before and during Heating Period in Tsinghua Yard,Beijing

采用美国rp公司生产的Series5400大气颗粒物碳质组分监测仪对清华园PM10中的碳质组分进行了连续在线监测（2002年9月-11月）。结合PM2.5中碳质组分浓度、PM10的浓度和气象数据，分析了碳质组分的污染特征。结果表明，采样期间清华园大气PM10中有机碳（OC）、元素碳（EC）的日平均质量浓度分别在4．07～65．81μg／m^3、0．96～26．14μg／m^3之间变化，平均值分别为20．8±12．1和7．0±5．1μg／m^3。OC在总碳（TC）中占有很大比例，OC／TC平均值为75．84％；TC在PM10中的含量平均为25．0％。本文对9—10月份（秋季）和11月份（初冬）OC、EC的相关性分别进行了分析，结果表明OC、EC之间具有良好的相关性，9月份和10月份相关性系数（R^2）为0．83；11月份为0．90。二次生成的OC（OCsec）浓度估算结果表明，9、10月份OCsec在OC中的比例（60．7％）比11月份（38．5％）大。碳质组分主要集中在细颗粒物中，PM10中的OC有70．3％存在于细颗粒物PM2.5中，TC则有58．6％存在于PM2.5中。

Series5400 ambient particulate carbon monitor was used to study the carbonaceous species of PM10 in Tsinghua University from Sep. to Nov. 2002. The concentrations of PM10 and carbonaceous species in PM2.5 were also involved combining with meteorological data. During the sampling period, the average daily concentrations of organic carbon （OC） and elemental carbon （EC） ranged from 4.07 to 65.81μg/m^3 and from 0.96 to 26.14μg/m^3 , respectively, and the overall mean concentrations were 20.8 ± 12.1 and 7.0 ± 5.1μg/m^3 , respectively. OC was the abundant component, which accounted for 75.84 % of TC, while TC constituted 25.0 % of PM10. The correlations between OC and EC were analyzed for fall （Sep. ～ Oct. ） and early winter （November）. It indicated that there was good correlation between OC and EC. The R^2 was 0.83 for＇fall and 0.90 for early winter, respectively. The secondary OC to OC ratio was 60.7% in Sep.～ Oct., which was higher than that in November. 70.3% of OC and 58.6% of TC in PM10 existed in fine particles mode （ PM2.5 ）.