Optical properties of secondary organic aerosols derived from long-chain alkanes under various NOx and seed conditions
Optical properties of secondary organic aerosols derived from long-chain alkanes under various NOx and seed conditions
复制标题
不同NOx和种子条件下长链烷烃衍生的二次有机气溶胶的光学特性
DOI：
10.1016/j.scitotenv.2016.11.189
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发表时间：
2017
影响因子：
9.8
通讯作者：
Ge Maofa
中科院分区：
文献类型：
--
作者：
Li Junling;Li Kun;Wang Weigang;Wang Jing;Peng Chao;Ge Maofa
长链烷烃是大气中一种重要的中间挥发性有机化合物（IVOCs），在二次有机气溶胶（SOA）中占很大比例。然而，从长链烷烃衍生的SOA光学性质仍然知之甚少。在这里，我们研究了在低氧和高氧条件下，在没有或存在无机气溶胶种子的情况下，十二烷（C12）、十五烷（C15）和十七烷（C17）的光氧化得到的SOA的折射率（RI）。在532 nm波长处，这些soa的RIs在1.33 ~ 1.57之间。质谱分析结果表明，受nox水平影响的反应机制和受种子影响的气-颗粒分配对soa的化学成分有重要影响，进而影响其光学性质，如RI。最后，通过与其他文献和模式结果的RI值比较，我们建议将长链烷烃衍生的soa的各种RI值应用于大气和气候模式。
Long-chain alkanes are a type of important intermediate-volatile organic compounds (IVOCs) in the atmosphere, which contribute to a large proportion of secondary organic aerosol (SOA). However, the optical properties of SOA derived from long-chain alkanes remain poorly understood. Here, we investigate the refractive index (RI) of SOA derived from photo-oxidation of dodecane (C12), pentadecane (C15) and heptadecane (C17) under low-NOxand high-NOxconditions with the absence or presence of inorganic aerosol seeds. The RIs of these SOAs are found to be in the range of 1.33 to 1.57 at the wavelength of 532 nm. The results from mass spectroscopy indicate that both reaction mechanisms influenced by NOxlevel and gas-particle partitioning influenced by seeds have important impact on the chemical compositions of SOAs, which further influence the optical properties like RI. Finally, by comparing the RI values to other literature and model results, we suggest that various RIs of SOAs derived from long-chain alkanes should be applied in atmospheric and climate models.