气候变化领域集成服务门户(CCPortal): Predicting secondary organic aerosol phase state and viscosity and its effect on multiphase chemistry in a regional-scale air quality model

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DOI	10.5194/acp-20-8201-2020
	Predicting secondary organic aerosol phase state and viscosity and its effect on multiphase chemistry in a regional-scale air quality model
	Schmedding R.; Rasool Q.Z.; Zhang Y.; Pye H.O.T.; Zhang H.; Chen Y.; Surratt J.D.; Lopez-Hilfiker F.D.; Thornton J.A.; Goldstein A.H.; Vizuete W.
发表日期	2020
ISSN	1680-7316
起始页码	8201
结束页码	8225
卷号	20 期号:13
英文摘要	Atmospheric aerosols are a significant public health hazard and have substantial impacts on the climate. Secondary organic aerosols (SOAs) have been shown to phase separate into a highly viscous organic outer layer surrounding an aqueous core. This phase separation can decrease the partitioning of semi-volatile and low-volatile species to the organic phase and alter the extent of acidcatalyzed reactions in the aqueous core. A new algorithm that can determine SOA phase separation based on their glass transition temperature (Tg), oxygen to carbon (O V C) ratio and organic mass to sulfate ratio, and meteorological conditions was implemented into the Community Multiscale Air Quality Modeling (CMAQ) system version 5.2.1 and was used to simulate the conditions in the continental United States for the summer of 2013. SOA formed at the ground/surface level was predicted to be phase separated with core shell morphology, i.e., aqueous inorganic core surrounded by organic coating 65.4% of the time during the 2013 Southern Oxidant and Aerosol Study (SOAS) on average in the isoprene-rich southeastern United States. Our estimate is in proximity to the previously reported 70% in literature. The phase states of organic coatings switched between semi-solid and liquid states, depending on the environmental conditions. The semi-solid shell occurring with lower aerosol liquid water content (western United States and at higher altitudes) has a viscosity that was predicted to be 102 1012 Pa s, which resulted in organic mass being decreased due to diffusion limitation. Organic aerosol was primarily liquid where aerosol liquid water was dominant (eastern United States and at the surface), with a viscosity < 102 Pa s. Phase separation while in a liquid phase state, i.e., liquid liquid phase separation (LLPS), also reduces reactive uptake rates relative to homogeneous internally mixed liquid morphology but was lower than aerosols with a thick viscous organic shell. The sensitivity cases performed with different phase-separation parameterization and dissolution. © 2020 Copernicus GmbH. All rights reserved.
语种	英语
scopus关键词	aerosol; air quality; algorithm; catalysis; dissolution; parameterization; prediction; reaction kinetics; summer; viscosity; water content; United States
来源期刊	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/141219
作者单位	Department of Environmental Science and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516, United States; Office of Research and Development, Environmental Protection Agency, Research Triangle Park, Durham, NC 27709, United States; Department of Chemistry, University of California at Riverside, Riverside, CA 92521, United States; Aerodyne Research, Inc., Billerica, MA 01821, United States; Department of Atmospheric Sciences, University of Washington, Seattle, WA 98195, United States; Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA 94720, United States; Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720, United States; Department of Atmospheric and Oceanic Science, McGill University, Montreal, H3A 2K6, Canada; Pacific Northwest National Laboratory, Richland, WA 99354, United States; Tofwerk AG, Thun, 3600, Switzerland
推荐引用方式 GB/T 7714	Schmedding R.,Rasool Q.Z.,Zhang Y.,et al. Predicting secondary organic aerosol phase state and viscosity and its effect on multiphase chemistry in a regional-scale air quality model[J],2020,20(13).
APA	Schmedding R..,Rasool Q.Z..,Zhang Y..,Pye H.O.T..,Zhang H..,...&Vizuete W..(2020).Predicting secondary organic aerosol phase state and viscosity and its effect on multiphase chemistry in a regional-scale air quality model.Atmospheric Chemistry and Physics,20(13).
MLA	Schmedding R.,et al."Predicting secondary organic aerosol phase state and viscosity and its effect on multiphase chemistry in a regional-scale air quality model".Atmospheric Chemistry and Physics 20.13(2020).