Decreasing effect and mechanism of FeSO4 seed particles on secondary organic aerosol in α-pinene photooxidation
Decreasing effect and mechanism of FeSO4 seed particles on secondary organic aerosol in α-pinene photooxidation
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DOI：
10.1016/j.envpol.2014.06.018
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发表时间：
2014-10-01
影响因子：
8.9
通讯作者：
He, Hong
中科院分区：
文献类型：
--
作者：
Chu, Biwu;Liu, Yongchun;He, Hong
在有无FeSO4种子粒子的雾霾室内进行了不同湿度下的α-蒎烯/NOx和α-蒎烯/HONO光氧化实验。在相对湿度为12%的干燥条件下，FeSO4晶种颗粒在水分存在的情况下会降低SOA值，但FeSO4晶种粒子对SOA值没有影响。FeSO4晶种粒子对SOA值的降低作用可能与水表层氧化作用有关。Fe~(2+)和Fe~(3+)在水相中的催化循环可形成包括羟基在内的自由基。这些自由基可以进一步与种子颗粒上α-蒎烯氧化的有机产物反应。氧化可能会导致形成更小的分子，这些分子具有更高的饱和蒸汽压，有利于重新分配到气相，因此减少了SOA的质量。(C)2014年提交人。由爱思唯尔有限公司出版。这是CC BY-NC-ND许可证(http://creativecommons.org/licenses/by-nc-nd/3.0/).下的一篇开放获取文章
alpha-Pinene/NOx and alpha-pinene/HONO photooxidation experiments at varying humidity were conducted in smog chambers in the presence or absence of FeSO4 seed particles. FeSO4 seed particles decrease SOA mass as long as water was present on the seed particle surface, but FeSO4 seed particles have no decreasing effect on SOA under dryer conditions at 12% relative humidity (RH). The decreasing effect of FeSO4 seed particles on the SOA mass is proposed to be related to oxidation processes in the surface layer of water on the seed particles. Free radicals, including OH, can be formed from catalytic cycling of Fe2+ and Fe3+ in the aqueous phase. These radicals can react further with the organic products of alpha-pinene oxidation on the seed particles. The oxidation may lead to formation of smaller molecules which have higher saturation vapor pressures and favor repartitioning to the gas phase, and therefore, reduces SOA mass. (C) 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).