异戊二烯与OH自由基光化学反应的二次有机气溶胶的生成

Secondary organic aerosol formation from the photochemical reaction of isoprene with OH radical

利用烟雾箱模拟装置,研究了异戊二烯与OH自由基反应的二次有机气溶胶(SOA)的生成.反应中生成的气相产物通过质子转移反应质谱仪(PTR-MS)测定,SOA的浓度及粒径谱分布通过高分辨率粒径谱仪(EEPS3090)测定.研究表明:甲基丙烯醛(MAC)/甲基乙烯基酮(MVK)、乙醛、甲醛、甲醇、甲酸/乙醇、乙醇醛、甲基乙二醛、丙酮/丙醛等为主要气相产物,各组实验中MAC/MVK和乙醛浓度达到最大时,其产率分别介于13.78%～37.72%和5.38%～9.34%(以C计)范围内;SOA生成量及其中值粒径随异戊二烯反应量的增加而增加,气相物质稳定后,SOA产率在5.6%～11.7%范围内,粒径在22～165nm范围内.

Using smog chamber,Secondary organic aerosol （SOA） formation from the reaction of isoprene with OH radical was studied.Gaseous products were determined by proton-transfer-reaction mass spectrometer （PTR-MS） while SOA concentration and size distribution were determined by EEPS3090.The dominating gaseous products were methacrolein （MAC）/methyl vinyl ketone （MVK）,acetaldehyde,formaldehyde,methanol,formic acid/ethanol,glycollic aldehyde,methylglyoxal,acetone/propionaldehyde and so on.The highest production of MAC/MVK and acetaldehyde were 13.78% 37.72% and 5.38% 9.34% （based on C）.SOA production and its mean size increased with increasing reacted isoprene.When the gas phase products were stable,the SOA yields were in the range of 5.6% 11.7% and the particle sizes were from 22 nm to 165 nm.