西安市夏末秋初PM_(2.5)中碳组分分析
doi: 10.13205/j.hjgc.201505020
ANALYSIS OF CARBON COMPONENTS IN PM2. 5 DURING LATE SUMMER AND EARLY AUTUMN OF XI’AN CITY
-
摘要: 2012年9月1日至30日利用大气气溶胶OC/EC在线分析仪在线分析了西安PM2.5中的OC、EC,并结合O3和紫外辐射数据(UV)进行了分析。结果表明:PM2.5、OC、EC、及O3的日均值分别为85.22,19.50,7.18,56.69μg/m3。PM2.5及其中OC、EC的日变化规律呈现"双峰"分布,OC、EC的日波动范围较PM2.5小,且OC的波动范围较EC大,OC、EC的相关性较高(R2=0.73)。PM2.5中TCA的平均比重为47.85%,是PM2.5的主要成分之一,TCA以OM为主,OM中SOC的平均比重高达54.76%,PM2.5中SOC的平均比重为21.25%,SOC和O3的相关性较高,表明研究期间西安市有机物光化学反应较重。1 d中10:00至19:00是PM2.5中SOC比重最高的时段且呈上升趋势,而PM2.5中TCA的变化规律则呈"W"型双峰分布。Abstract: An on-line monitoring of OC,EC in PM2. 5 was done by OC/EC online analyzer from 1st to 30th September,2012 in Xi'an. O3 and UV were also monitored and analyzed. The results showed that the daily average concentration of PM2. 5 , OC,EC,O3 was 85. 22,19. 50,7. 18 and 56. 69 μg /m3 ,respectively. The daily change rules of PM2. 5 ,OC and EC were present“bimodal”distribution,and the daily changes of OC and EC were both smaller than PM2. 5 . Furthermore,OC had a larger fluctuation range than EC,while the relative correlation of them was high ( R2 = 0. 72899 ) . TCA was the main component of PM2. 5 and could occupy 47. 85% . The majority composition of TCA was OM,and the concentrations of SOC in the OM could be up to 54. 76% . SOC and O3 showed a high correlation,which indicated that the organic photochemical reactions were relatively heavy during the study period in Xi' an. The proportions of SOC in PM2. 5 were highest during 10: 00am to 7: 00pm in a day,and did a increasing trend,The changes of TCA in the PM2. 5 were present“W shape” bimodal distribution.
点击查看大图
计量
- 文章访问数: 99
- HTML全文浏览量: 6
- PDF下载量: 128
- 被引次数: 0