Direct contribution of ammonia to CCN-size alpha-pinene secondary organic aerosol formation

doi:10.5194/acp-2020-457

GSTDTAP > 地球科学

DOI	10.5194/acp-2020-457
	Direct contribution of ammonia to CCN-size alpha-pinene secondary organic aerosol formation
	Liqing Hao, Eetu Kari, Ari Leskinen, Douglas R. Worsnop, and Annele Virtanen
	2020-05-14
发表期刊	Atmospheric Chemistry and Physics
出版年	2020
英文摘要	Ammonia (NH₃), a gasous compound ubiquitiously present in the atmosphere, is involved in the formation of secondary organic aerosol (SOA), but the exact mechanisum is still not well known. This study presents the results of SOA experiments from the photooxidation of α-pinene in the presence of NH₃ in the reaction chamber. SOA was formed in nucleation experiment and in seeded experiment with ammonium sulfate particles as seeds. The chemical composition and time-series of compounds in the gas- and particle- phase were characterized by an on-line high-resolution time-of-flight proton transfer reaction mass spectrometer (HR-ToF-PTRMS) and a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS), respectively. Our results show that for the aerosol particles in cloud condensation nuclei (CCN) size, the mass concentration of ammonium (NH₄⁺) was still rising even after the mass concentration of organic component started to decrease due to aerosol wall deposition and evaporation, implying the continuous new formation of particle phase ammonium in the process. Stoichiometric neutralization analysis of aerosol indicates that organic acids have a central role in the formation of particle phase ammonium. Our measurements show a good correlation between the gas phase organic mono- and di-carboxylic acids formed in the photooxidation of α-pinene and the ammonium in the particle phase, thus highlighting the contribution of gas-phase organic acids to the ammonium formation in the CCN-size SOA particles. The work shows that the gas-phase organic acids contribute to the SOA formation by forming ammonium salts through acid-base reaction. The changes in aerosol mass, particle size and chemical composition resulting from the NH₃-SOA interaction can potentially alter the aerosol direct and indirect forcing and therefore alter its impact on climate change.
领域	地球科学
URL	查看原文
引用统计
文献类型	期刊论文
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/267591
专题	地球科学
推荐引用方式 GB/T 7714	Liqing Hao, Eetu Kari, Ari Leskinen, Douglas R. Worsnop, and Annele Virtanen. Direct contribution of ammonia to CCN-size alpha-pinene secondary organic aerosol formation[J]. Atmospheric Chemistry and Physics,2020.
APA	Liqing Hao, Eetu Kari, Ari Leskinen, Douglas R. Worsnop, and Annele Virtanen.(2020).Direct contribution of ammonia to CCN-size alpha-pinene secondary organic aerosol formation.Atmospheric Chemistry and Physics.
MLA	Liqing Hao, Eetu Kari, Ari Leskinen, Douglas R. Worsnop, and Annele Virtanen."Direct contribution of ammonia to CCN-size alpha-pinene secondary organic aerosol formation".Atmospheric Chemistry and Physics (2020).