烟雾箱模拟丙烯-NO_x的大气光化学反应

Smog Chamber Simulation of Atmospheric Photochemical Reactions of Propene and NO_x

利用自制烟雾箱对丙烯-NOx的光化学反应进行了一系列模拟实验,研究了相对湿度及丙烯与NOx的初始浓度比值对丙烯-NOx光化学反应产物如O3和CO的影响.实验得到了臭氧最大值、CO最大值及反应掉的C3H6均随相对湿度的增加而减少,丙烯的臭氧生成活性最大值(IRmax)也随着相对湿度的增加而减小,且两者间存在显著的线性关系.丙烯与NOx的比值对反应生成臭氧最大值的影响出现两种情况:当初始浓度比值在1.0～3.4之间时,臭氧最大值随着该比值的增加而有大幅度提高;而当该比值分别在3.7～7.4之间时,臭氧最大值随比值的增加而有小幅度的下降.此外,本研究还利用丙烯MCMv3.1机理对反应进行了数值模拟.

A series of experiments was conducted in a self-made photochemical smog chamber in order to simulate atmospheric photochemical reactions of propene and NOx.The effects of both relative humidity（RH） and the initial C3H6 to NOx concentration（0/0） ratio on the ozone and CO production in the photochemical reactions were mainly investigated in this paper.Results show that the maximum concentra-tions of ozone and CO,as well as the concentration of reacted propene linearly decrease with increasing RH.The maximum value of incremental reactivity（IRmax） for propene also declines as RH increases.Their rela-tionships with RH are statistically significant.The effects of 0/0 on the maximum ozone concen-tration show two different trends.When the ratio is within 1.0～3.4,the maximum ozone concentration greatly increases with increasing ratio,whereas for the ratio of 3.7 to 7.4,it gradually decreases as the ratio increases.The comparison between smog-chamber data and results from the propene sub-mechanism of MCMv3.1 is also made in this work.