TY - JOUR
T1 - Ionic composition of TSP and PM2.5 during dust storms and air pollution episodes at Xi'an, China
AU - Shen, Zhenxing
AU - Cao, Junji
AU - Arimoto, Richard
AU - Han, Zhiwei
AU - Zhang, Renjian
AU - Han, Yuemei
AU - Liu, Suixin
AU - Okuda, Tomoaki
AU - Nakao, Shunsuke
AU - Tanaka, Shigeru
N1 - Funding Information:
We thank two anonymous reviewers for their constructive suggestions and comments. This work was supported in part by the Natural Science Foundation of China (grants 40875089 and 40675081), the Chinese National Key Project of Basic Research (grant G2004CB720200), the SKLLQG, Chinese Academy of Sciences (grant SKLLQG0811), National Science Foundation of the United States (grant ATM 0404944), The Ministry of Education, Culture, Sports, Science and Technology of Japan (grants 13480160, 14048220, 16030209, 16404002, 16710008, and 18710014), Steel Industry Foundation for the Advancement of Environmental Protection Technology, the Iwatani Naoji Foundation's Research Grant, and Heiwa Nakajima Foundation, Japan. Any opinions, findings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of the sponsors.
PY - 2009/6
Y1 - 2009/6
N2 - TSP and PM2.5 samples were collected at Xi'an, China during dust storms (DSs) and several types of pollution events, including haze, biomass burning, and firework displays. Aerosol mass concentrations were up to 2 times higher during the particulate matter (PM) events than on normal days (NDs), and all types of PM led to decreased visibility. Water-soluble ions (Na+, NH4+, K+, Mg2+, Ca2+, F-, Cl-, NO3-, and SO42-). were major aerosol components during the pollution episodes, but their concentrations were lower during DSs. NH4+, K+, F-, Cl-, NO3-, and SO42- were more abundant in PM2.5 than TSP but the opposite was true for Mg2+ and Ca2+. PM collected on hazy days was enriched with secondary species (NH4+, NO3-, and SO42) while PM from straw combustion showed high K+ and Cl-. Firework displays caused increases in K+ and also enrichments of NO3- relative to SO42-. During DSs, the concentrations of secondary aerosol components were low, but Ca2+ was abundant. Ion balance calculations indicate that PM from haze and straw combustion was acidic while the DSs samples were alkaline and the fireworks' PM was close to neutral. Ion ratios (SO42-/K+, NO3-/SO42-, and Cl-/K+) proved effective as indicators for different pollution episodes.
AB - TSP and PM2.5 samples were collected at Xi'an, China during dust storms (DSs) and several types of pollution events, including haze, biomass burning, and firework displays. Aerosol mass concentrations were up to 2 times higher during the particulate matter (PM) events than on normal days (NDs), and all types of PM led to decreased visibility. Water-soluble ions (Na+, NH4+, K+, Mg2+, Ca2+, F-, Cl-, NO3-, and SO42-). were major aerosol components during the pollution episodes, but their concentrations were lower during DSs. NH4+, K+, F-, Cl-, NO3-, and SO42- were more abundant in PM2.5 than TSP but the opposite was true for Mg2+ and Ca2+. PM collected on hazy days was enriched with secondary species (NH4+, NO3-, and SO42) while PM from straw combustion showed high K+ and Cl-. Firework displays caused increases in K+ and also enrichments of NO3- relative to SO42-. During DSs, the concentrations of secondary aerosol components were low, but Ca2+ was abundant. Ion balance calculations indicate that PM from haze and straw combustion was acidic while the DSs samples were alkaline and the fireworks' PM was close to neutral. Ion ratios (SO42-/K+, NO3-/SO42-, and Cl-/K+) proved effective as indicators for different pollution episodes.
KW - PM
KW - Pollution episodes
KW - TSP
KW - Water-soluble ions
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U2 - 10.1016/j.atmosenv.2009.03.005
DO - 10.1016/j.atmosenv.2009.03.005
M3 - Article
AN - SCOPUS:65549151398
VL - 43
SP - 2911
EP - 2918
JO - Atmospheric Environment
JF - Atmospheric Environment
SN - 1352-2310
IS - 18
ER -