期刊
ACS EARTH AND SPACE CHEMISTRY
卷 6, 期 10, 页码 2481-2490出版社
AMER CHEMICAL SOC
DOI: 10.1021/acsearthspacechem.2c00195
关键词
aerosol particles; organosulfates; gas-particle partitioning; hygroscopicity; viscosity; environmental chamber; aerosol mass spectrometry
资金
- Environmental Chemical Sciences of the Division of Chemistry of the USA National Science Foundation [2003368, 2003359]
- Schmidt Science Fellowship in Partnership
- Rhodes Trust
- Harvard University Center for the Environment
- European Union [840217, 890200]
- Natural Sciences and Engineering Research Council of Canada (NSERC) [RGPIN/04441-2016]
- Marie Curie Actions (MSCA) [890200, 840217] Funding Source: Marie Curie Actions (MSCA)
- Division Of Chemistry
- Direct For Mathematical & Physical Scien [2003359, 2003368] Funding Source: National Science Foundation
Organosulfate particles, with their high hygroscopicity and viscosity, play a crucial role in gas-particle interactions in the Earth's atmosphere. The uptake of these particles is affected by environmental humidity and nitrogen oxide concentrations, while viscosity and kinetic limitations have minimal impact on the uptake. These findings are significant for simplifying models of atmospheric chemistry and pollutant transport.
Organosulfate compounds make up a substantial fraction of the particle mass concentration in some regions of the Earth's atmosphere, and organosulfate particles can have sufficiently high viscosity to limit rates of gas-particle interactions. Viscosity varies with relative humidity (RH). Herein, organosulfate particles were exposed to the gas-phase products of alpha- pinene photooxidation. The gas-particle partitioning of these species was studied from 15 to 70% RH and < 1 to 16 ppb NO at 299 K. The uptake of the alpha-pinene oxidation products increased with the increase in RH, and higher gas-phase NO concentrations resulted in increased particle-phase concentrations of nitrogen compounds. Particle hygroscopicity was examined by optical microscopy. Hygroscopic growth at elevated RH was sufficient to explain the RH-dependent uptake measurements, and kinetic limitations tied to particle viscosity were not observed. The lack of kinetic limitations combined with the Stokes-Einstein equation implied a viscosity much less than 1 x 106 Pa s. This value is consistent with estimated viscosities based on literature parameterizations for water mass fractions in the particles of at least 0.05 at 15% RH. Overall, these results suggest that organosulfate hygroscopicity plays a key role in their viscosity and hence in regulating gas-particle partitioning, thereby simplifying the treatment of atmospheric chemistry and transport of pollutants in models of the Earth's atmosphere. The role of organosulfates is expected to take on increasing importance for projected future emission trends.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据