仲丁醇对苯乙烯臭氧化反应生成二次有机气溶胶的影响:实验和模型研究

Influence of 2-butanol on secondary organic aerosol formation from ozonolysis of styrene: Experimental and model studies

通过烟雾箱实验,研究了仲丁醇对苯乙烯臭氧化反应生成二次有机气溶胶(SOA)的影响.结果发现,在烟雾箱实验中,过量仲丁醇的加入导致生成SOA的产率明显下降.同时,结合MCM气相机理和气-粒分配理论,将Criegee中间体与醛类的双分子反应添加到箱式模型中模拟烟雾箱中SOA的生成过程.模拟结果表明,在没有仲丁醇存在的情况下,次级臭氧化物在SOA组分中占1/2左右的比例.仲丁醇的加入消耗了大量的·OH,同时使得[HO_2]/[RO_2]比值升高,影响自由基相关的反应机制,使得SOA产率下降.另外,研究发现,Criegee中间体与醛类反应的速率常数也是影响SOA生成模拟的一个重要参数,需要进一步开展相关的动力学实验和理论研究.

Influence of 2-butanol on secondary organic aerosol（ SOA） formation from ozonolysis of styrene was studied using chamber experiments and model simulations in this work. The experimental results showed that the introduction of 2-butanol results in a decrease of SOA yield. Then,the reactions between Criegee intermediates with aldehydes were implemented into the master chemical mechanism（ MCM） coupled with a gas-particle partitioning model to investigate their impact on SOA formation. And it is shown that the secondary ozonide accounts for about half of the SOA yield in the absence of 2-butanol. While the introducing of 2-butanol will result in the decrease of [OH] and the increase of [HO2]/[RO2]ratio,which is proposed to be the main factor leading to the decreases of SOA yield. In addition,it is found that the magnitude of SOA yield exhibits a strong dependence on the rate constants of the reactions between Criegee intermediates with aldehydes,which needs further experimental and theoretical studies in the future.