|
Hokkaido University Collection of Scholarly and Academic Papers >
Institute of Low Temperature Science >
Peer-reviewed Journal Articles, etc >
Dicarboxylic acids and water-soluble organic carbon in aerosols in New Delhi, India, in winter : Characteristics and formation processes
Title: | Dicarboxylic acids and water-soluble organic carbon in aerosols in New Delhi, India, in winter : Characteristics and formation processes |
Authors: | Miyazaki, Yuzo Browse this author →KAKEN DB | Aggarwal, Shankar G. Browse this author | Singh, Khem Browse this author | Gupta, Prabhat K. Browse this author | Kawamura, Kimitaka Browse this author →KAKEN DB |
Issue Date: | 8-Oct-2009 |
Publisher: | American Geophysical Union |
Journal Title: | Journal of Geophysical Research : Atmospheres |
Volume: | 114 |
Start Page: | D19206 |
Publisher DOI: | 10.1029/2009JD011790 |
Abstract: | Day-and night-time aerosol samples were collected at an urban site in New Delhi, India, in winter 2006-2007. They were studied for low molecular weight dicarboxylic acids and related compounds, as well as total water-soluble organic carbon (TWSOC). High concentrations of diacids (up to 6.03 μg m^[-3]), TWSOC, and OC were obtained, which are substantially higher than those previously observed at other urban sites in Asia. Daytime TWSOC/OC ratio (37%) was on average higher than that in nighttime (25%). In particular, more water-soluble OC (M-WSOC) to TWSOC ratio in daytime (50%) was twice higher than in nighttime (27%), suggesting that aerosols in New Delhi are photochemically more processed in daytime to result in more water-soluble organic compounds. Oxalic acid (C2) was found as the most abundant dicarboxylic acid, followed by succinic (C4) and malonic (C3) acids. Contributions of C2 to M-WSOC were greater (av. 8%) in nighttime than daytime (av. 3%). Positive correlations of C2 with malic acid (hC4), glyoxylic acid (ωC2), and relative humidity suggest that secondary production of C2 probably in aqueous phase is important in nighttime via the oxidation of both longer-chain diacids and ωC2. C2 also showed a positive correlation with potassium (K+) in nighttime, suggesting that the enhanced C2 concentrations are associated with biomass/biofuel burning. More tight, positive correlation between less water-soluble OC (L-WSOC) and K+ was found in both day- and night-time, suggesting that L-WSOC, characterized by longer chain and/or higher molecular weight compounds, is significantly influenced by primary emissions from biomass/biofuel burning. |
Rights: | An edited version of this paper was published by AGU. Copyright 2009 American Geophysical Union. |
Type: | article (author version) |
URI: | http://hdl.handle.net/2115/39604 |
Appears in Collections: | 低温科学研究所 (Institute of Low Temperature Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
Submitter: 宮崎 雄三
|