采用"SUMMA罐采样—GC-MS"离线分析方法,通过对北京市东部城区2014年10月16日~11月27日大气环境挥发性有机化合物(VOCs)监测,得出APEC期间VOCs结果,会议前(10月16~30日)、会议期(11月5~11日)、会议后(11月12~27日),TVOCs(检出VOCs化合物之和)24h日平均浓度分别为49.12×10-9、25.17×10-9、23.38×10-9,随时间呈下降趋势;而3个时间段,TVOCs白天平均浓度分别为41.43×10-9、17.36×10-9、20.08×10-9,会议期浓度最低,且烯烃体积百分比升高,烷烃和芳香烃降低,与会议前、后VOCs化学组分特征形成显著差异.会议前、会议后的TVOCs浓度与气象要素的相关性分析表明:VOCs受温度影响最大(相关性0.74),其次相对湿度(相关性0.67),与风速相关性不显著.最后,基于北京市VOCs排放清单和主要源VOCs化学成分谱,核算了会议期15种主要化合物的日减排量.APEC期间,该15种化合物的减排量与其白天均浓度较会议前、后的下降量显著相关,相关性达到0.76~0.80,间接校验了北京市VOCs排放清单的准确性.%The ambient VOCs were monitored in the eastern urban area of Beijing city from October 16th to November 27th, 2014. They were analyzed by an off-line analysis method of SUMMA tank sampling and GC-MS. The VOCs results during APEC showed that the 24h daily average concentrations of TVOCs were 49.12×10-9, 25.17×10-9 and 23.38×10-9 respectively during Oct 16~30 (before APEC), Nov 5~11 (APEC) and Nov 12~27 (after APEC), presenting a falling trend with time; however, the daytime average concentrations (8:00~18:00) were 41.43×10-9, 17.36×10-9 and 20.08×10-9 respectively, the lowest daytime concentrations happened during APEC. Meanwhile, the VOCs chemical profiles also showed obvious differences between APEC and before/after APEC, volume mixing ratio of alkenes increasing and those of alkanes and aromatics decreasing. Then the relationship between VOCs and meteorological factors was concluded, based on the VOCs data before and after APEC, the most important impact being from temperature (r = 0.74), followed by the relative humidity (r = 0.67) and no significant correlation with wind speed. Finally, the reduction emissions of the 15main compounds were calculated by using Beijing VOCs emission inventory and VOCs chemical profiles of various sources. A great well correlation between their emission abatement and their daytime average concentration change during APEC were found, with the correlation coefficient of 0.76~0.80, which verified the accuracy of Beijing VOCs emission inventory.
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