Aerosol-chamber study of the α-pinene/O3 reaction:: influence of particle acidity on aerosol yields and products
Aerosol-chamber study of the α-pinene/O3 reaction:: influence of particle acidity on aerosol yields and products
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DOI：
10.1016/j.atmosenv.2003.10.015
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发表时间：
2004-02-01
影响因子：
5
通讯作者：
Herrmann, H
中科院分区：
文献类型：
--
作者：
Iinuma, Y;Böge, O;Herrmann, H
在9 m3聚四氟乙烯反应器中，在硫酸铵或硫酸种子颗粒存在下，以100 ppbv（α-蒎烯）和70 ppbv（臭氧）的混合比进行α-蒎烯的臭氧分解。通过微分迁移率粒度仪（DMPS）测量尺寸分布的演变。通过扩散管/石英纤维过滤器组合对产生的二次有机气溶胶（SOA）进行采样，以测定颗粒相中的总有机碳浓度（TOC），使用热成像方法和扩散器/PTFE过滤器组合，使用毛细管电泳电喷雾电离质谱法分析颗粒相中的单个化学物质顺式-蒎酸（m/z 185）和在m/z 171和199处初步鉴定的另一种物质是两种种子颗粒的主要颗粒相物质，尽管产物产率不同，表明种子颗粒酸度的影响。用于测定TOC的热像法表明颗粒相有机物增加了40%对于酸度较高的实验。CE-ESI-MS分析显示来自使用硫酸晶种颗粒的实验的M-w > 300的化合物的浓度大幅增加。这些结果表明，种子颗粒的酸性提高SOA的产率，并在形成较大的分子在颗粒相中起着重要的作用。我们的直接颗粒相化学分析的结果表明，第一次，较小的有机物的缩合发生聚合或羟醛缩合后形成的醛，如从萜烯臭氧分解的pinonaldehyde。(C)2003爱思唯尔有限公司。保留所有权利。
a-Pinene ozonolysis was carried out in the presence of ammonium sulfate or sulfuric acid seed particles in a 9 m 3 Teflon chamber at the mixing ratios of 100ppbv for alpha-pinene and about 70 ppbv for ozone. The evolution of size distribution was measured by means of a differential mobility particle sizer (DMPS). The resulting secondary organic aerosol (SOA) was sampled by a denuder/quartz fiber filter combination for the determination of the total organic carbon concentration (TOC) in the particle phase, using a thermographic method and by a denuder/PTFE filter combination for the analysis of individual chemical species in the particle phase using capillary electrophoresiselectrospray ionization-mass spectrometry (CE-ESI-MS).cis-Pinic acid (m/z 185) and another species tentatively identified at m/z 171 and 199 were the major particle phase species for both seed particles although the product yields were different, indicating the influence of seed particle acidity.A thermographic method for the determination of TOC showed an increase of particle phase organics by 40% for the experiments with higher acidity. CE-ESI-MS analysis showed a large increase in the concentration of compounds with M-w > 300 from the experiments with sulfuric acid seed particles. These results suggest that the seed particle acidity enhances the yield of SOA and plays an important role in the formation of larger molecules in the particle phase. Our results from direct particle phase chemical analysis suggest for the first time that condensation of smaller organics takes place by polymerization or aldol condensation following the formation of aldehydes, such as pinonaldehyde from the terpene ozonolysis. (C) 2003 Elsevier Ltd. All rights reserved.