Size‐Resolved Characterization of the Chromophores in Atmospheric Particulate Matter From a Typical Coal‐Burning City in China. Issue 19 (16th October 2019)

• Record Type: Journal Article
• Authors: Chen, Qingcai; Mu, Zhen; Song, Wenhuai; Wang, Yuqin; Yang, Zhaohong; Zhang, Lixin; Zhang, Yan‐Lin
• Is Part Of: Journal of geophysical research. Volume 124:Issue 19(2019)
• Page Start: 10546
• Page End: 10563
• Publication Date: 2019-10-16
• Subjects: atmospheric chromophores -- excitation‐emission matrix (EEM) -- size‐resolved characterizations -- parallel factor analysis (PARAFAC); Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1029/2019JD031149
• Languages: English
• ISSNs: 2169-897X

Abstract

Abstract: This study reports the size‐resolved characterization of the chromophores in atmospheric particulate matter in Linfen, a typical coal‐burning city in China. The optical properties of both the water‐soluble and water‐insoluble chromophores in atmospheric particulates are studied using excitation‐emission matrix spectroscopy and follow the parallel factor analysis of excitation‐emission matrix data. The mass absorption efficiency and normalized fluorescence volume by mass concentration of the organic carbon in methanol‐soluble matter in the particulate samples are stronger than that of the water‐soluble matter. We found that the total absorption (Abs), fluorescence volume (FV), mass absorption efficiency, and normalized fluorescence volume of particle extracts with sizes less than 10 μm increased with the decreasing particle size. The total concentration of the selected seven polycyclic aromatic hydrocarbons was positively correlated with the Abs365 and FV of both the water‐soluble matter and methanol‐soluble matter, but the average contribution of the selected polycyclic aromatic hydrocarbons to the total Abs and FV was very small (<3%). This study is the first to report a size‐resolved characterization of the chromophores in atmospheric particulate matter. Humic‐like substances tend to be present in small particles, and tryptophan‐like and tyrosine‐like components tend to increase with increasing particle size. Key Points: The total light absorption and fluorescence volume of particle extracts increased with the decrease in particle size The selected seven polycyclic aromatic hydrocarbons were positively correlated with the light absorption of particle extracts This study is the first to report the particle size distribution characteristics of chromophores in Linfen