Laboratory of Environmental Spectroscopy, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China.
J Environ Sci (China). 2009;21(11):1525-31. doi: 10.1016/s1001-0742(08)62450-x.
Photooxidation of isoprene leads to the formation of secondary organic aerosol (SOA). In this study, the chemical composition of SOA formed from OH-initiated photooxidation of isoprene has been investigated with gas chromatography/mass spectrometry (GC/MS) and a home-made aerosol time-of-flight mass spectrometer. Sampling particles generated in a home-made smog chamber. The size distribution of SOA particles was detected by a TSI 3321 aerodynamic particle size spectrometer in real time. Results showed that SOA created by isoprene photooxidation was predominantly in the form of fine particles, which have diameters less than 2.5 microm. The obtained mass spectra of individual particles show that products of the OH-initiated oxidation of isoprene contain methyl vinyl ketone, methacrolein, formaldehyde, and some other hydroxycarbonyls. The possible reaction mechanisms leading to these products were also discussed.
异戊二烯的光氧化导致了二次有机气溶胶（SOA）的形成。在这项研究中，利用气相色谱/质谱（GC/MS）和自制的气溶胶飞行时间质谱仪研究了由 OH 引发的异戊二烯光氧化形成的 SOA 的化学成分。通过自制的烟雾箱对生成的粒子进行采样。利用 TSI 3321 空气动力学粒径谱仪实时检测 SOA 粒子的粒径分布。结果表明，异戊二烯光氧化生成的 SOA 主要以细颗粒的形式存在，其直径小于 2.5 微米。对单个粒子的质谱分析表明，OH 引发的异戊二烯氧化产物中含有甲基乙烯基酮、甲基丙烯醛、甲醛和其他一些羟基羰基化合物。还讨论了导致这些产物的可能反应机制。
