气候变化领域集成服务门户(CCPortal): Light absorption properties of brown carbon (BrC) in autumn and winter in Beijing: Composition, formation and contribution of nitrated aromatic compounds

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DOI	10.1016/j.atmosenv.2020.117289
	Light absorption properties of brown carbon (BrC) in autumn and winter in Beijing: Composition, formation and contribution of nitrated aromatic compounds
	Li X.; Yang Y.; Liu S.; Zhao Q.; Wang G.; Wang Y.
发表日期	2020
ISSN	1352-2310
卷号	223
英文摘要	Nitro-aromatic compounds (NACs) are an important part of brown carbon because of their strong light absorbing properties in the visible and near ultraviolet regions. In this study, the concentration and formation mechanism of eight NACs, as well as their relative contribution to the light absorption of methanol-extracted BrC, were determined from fine particle samples collected in Beijing using ultra-high performance liquid chromatography coupled with high resolution mass spectrometry and ultraviolet–visible light spectrophotometry. The average concentrations of the eight NACs were 20.27 ± 12.40 ng m−3 and 74.17 ± 50.66 ng m−3 in autumn and winter, respectively. Among the detected NACs, 4-nitrophenol (4NP) and 4-nitrocatechol (4NC) were the most abundant compounds. The correlation analysis showed that the NACs other than 2,4-dinitrophenol (2,4-DNP) are strongly intercorrelated. Significant correlations among nitro catechols (NCs), nitro salicylic acids (NSAs) and NO2 support their proposed origin from secondary formation in the presence of •OH + NO2 (daytime process) or •NO3+NO2 (nighttime process). Significant correlations among nitrate, sulfate and NSAs were also found, indicating that the nitration of salicylic acid by nitric acid and sulfuric acid was another possible mechanism formation of NSAs. The methanol-extracts in winter had much higher light absorption than those in autumn, which is in agreement with the trend of NACs but contrary to the trends of PM2.5, water soluble ions, organic carbon and elemental carbon. The average absorption Ångström exponents (AAEs) during autumn and winter were 4.62 and 5.55, respectively, suggesting that secondary transformation were the main sources of BrC. The light absorption of NACs accounted for 1.17% and 3.18% of the total methanol-soluble BrC light absorption at λ = 365 nm in autumn and winter, respectively, while their masses only accounted for 0.16% and 0.44% of the OC, respectively, demonstrating that although NACs are not the major contributor to BrC, but they are strong BrC chromophores, and their influence on solar radiation should be included in future modeling work. © 2020
关键词	Brown carbon Formation pathway Light absorption Nitro-aromatic compounds
语种	英语
scopus关键词	Absorption spectroscopy; Aromatization; Chromophores; Extraction; High performance liquid chromatography; Light; Light absorption; Mass spectrometry; Methanol; Nitration; Nitrogen oxides; Organic carbon; Salicylic acid; Sulfur compounds; Water absorption; Average concentration; Brown carbons; Formation pathways; High resolution mass spectrometry; Near-ultraviolet regions; Nitro aromatic compounds; Secondary transformation; Ultra-high performance liquid chromatographies; Bromine compounds; 2,4 dinitrophenol; 4 nitrocatechol; 4 nitrophenol; aromatic compound; brown carbon; carbon; catechol derivative; methanol; nitrate; organic carbon; salicylic acid; salicylic acid derivative; sulfate; sulfuric acid; unclassified drug; absorption; aromatic hydrocarbon; brown carbon; chemical composition; concentration (composition); extraction method; formation mechanism; nitric acid; organic carbon; salicylic acid; sulfuric acid; transformation; Article; autumn; biomass; chemical composition; China; concentration (parameter); light absorption; mass spectrometry; meteorology; nitration; particulate matter; priority journal; reaction analysis; seasonal variation; solar radiation; ultra performance liquid chromatography; ultraviolet visible spectrophotometry; winter; Beijing [China]; China
来源期刊	ATMOSPHERIC ENVIRONMENT
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/249353
作者单位	Department of Chemistry, Analytical and Testing Center, Capital Normal University, Beijing, 100048, China; Key Laboratory of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai, 200241, China; College of Resource Environment and Tourism, Capital Normal University, Beijing, 100048, China; State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
推荐引用方式 GB/T 7714	Li X.,Yang Y.,Liu S.,et al. Light absorption properties of brown carbon (BrC) in autumn and winter in Beijing: Composition, formation and contribution of nitrated aromatic compounds[J],2020,223.
APA	Li X.,Yang Y.,Liu S.,Zhao Q.,Wang G.,&Wang Y..(2020).Light absorption properties of brown carbon (BrC) in autumn and winter in Beijing: Composition, formation and contribution of nitrated aromatic compounds.ATMOSPHERIC ENVIRONMENT,223.
MLA	Li X.,et al."Light absorption properties of brown carbon (BrC) in autumn and winter in Beijing: Composition, formation and contribution of nitrated aromatic compounds".ATMOSPHERIC ENVIRONMENT 223(2020).