Growth of Aitken mode ammonium sulfate particles by α-pinene ozonolysis
Growth of Aitken mode ammonium sulfate particles by α-pinene ozonolysis
复制标题
α-蒎烯臭氧分解法生长艾特肯模式硫酸铵颗粒
DOI：
10.1080/02786826.2019.1568381
复制
发表时间：
2019
影响因子：
5.2
通讯作者：
Johnston, Murray V.
中科院分区：
文献类型：
--
作者：
Krasnomowitz, Justin M.;Apsokardu, Michael J.;Stangl, Christopher M.;Tiszenkel, Lee;Ouyang, Qi;Lee, Shanhu;Johnston, Murray V.
长得足够大以充当云凝结核的艾特肯模式粒子的比例是了解大气粒子对气候影响的重要因素。要阐明该尺寸范围内的颗粒生长速率，需要详细了解这些颗粒生长的机制。在这里，对流管反应器进行了描述、表征，然后用于研究在干燥条件（10% RH）下通过 α-蒎烯臭氧分解在艾特肯模式尺寸范围内硫酸铵种子颗粒的生长。当直径从 40、60 或 80 nm 开始的选定尺寸的颗粒暴露于 α-蒎烯 (11 ppbv) 和臭氧（30 至 250 ppbv 之间的五种单独混合比）时，发现颗粒生长取决于反应的 α-蒎烯量和冷凝槽，但不直接取决于初始种子粒径。观察到的依赖性与缩合生长机制一致，这并不奇怪，因为实验的干燥条件最大限度地减少了种子颗粒内多相化学的可能性。将测量的颗粒生长与动力学模型结合起来，臭氧分解反应产生的可冷凝有机分子的摩尔产率为 13%。该值略高于之前报道的化学电离质谱在气相中测量的高度氧化分子 (HOM) 的摩尔产率，后者在 3-7% 范围内。讨论了气相和颗粒相测量确定的摩尔产率之间的关系。版权所有 © 2019 美国气溶胶研究协会
The fraction of Aitken mode particles that grow sufficiently large to act as cloud condensation nuclei is an important factor in understanding the climate impact of atmospheric particles. Elucidating the rate of particle growth in this size range requires a detailed understanding of the mechanisms by which these particles grow. Here, a flow tube reactor is described, characterized and then used to study growth of ammonium sulfate seed particles in the Aitken mode size range by α-pinene ozonolysis under dry conditions (10% RH). When size-selected particles starting at 40, 60, or 80 nm diameter were exposed to α-pinene (11 ppbv) and ozone (five separate mixing ratios between 30 and 250 ppbv), particle growth was found to depend on the amount of α-pinene reacted and the condensation sink, but not directly dependent on the initial seed particle diameter. The observed dependencies are consistent with a condensational growth mechanism, which is not surprising since the dry conditions of the experiment minimized the probability of multiphase chemistry within the seed particles. Combining the measured particle growth with a kinetic model gave a molar yield of 13% for condensable organic molecules produced by the ozonolysis reaction. This value is somewhat higher than previously reported molar yields of highly oxidized molecules (HOMs) measured in the gas phase with chemical ionization mass spectrometry, which are in the 3–7% range. The relationship between molar yields determined from gas phase and particle phase measurements is discussed.Copyright © 2019 American Association for Aerosol Research
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DOI：
--
发表时间：
2003
期刊：
影响因子：
--
作者：
M. Komppula;H. Lihavainen;J. Hatakka;J. Paatero;P. Aalto;M. Kulmala;Y. Viisanen
通讯作者：
Y. Viisanen
影响因子：
7.4
作者：
Tu P;Hall WA 4th;Johnston MV
通讯作者：
Johnston MV
影响因子：
3.8
作者：
Huang, Yuanlong;Coggon, Matthew M.;Seinfeld, John H.
通讯作者：
Seinfeld, John H.
根据停留时间分布得出连续流气溶胶反应器中冷凝生长后的粒径分布：二次有机气溶胶的理论发展和应用
影响因子：
5.2
作者：
M. Kuwata;S. Martin
通讯作者：
S. Martin