Please use this identifier to cite or link to this item:
標題: Characteristics of gaseous HNO2, HNO3, NH3 and particulate ammonium nitrate in an urban city of Central Taiwan
作者: Lin, Y.C.
Cheng, M.T.
Ting, W.Y.
Yeh, C.R.
關鍵字: acidic gases;ammonium nitrate;nitrogen conversion ratio;annular;denuder system;daytime;nighttime;acidic air-pollutants;nitric-acid;new-york;sulfate;aerosol;region;greece;pm2.5;oh
Project: Atmospheric Environment
期刊/報告no:: Atmospheric Environment, Volume 40, Issue 25, Page(s) 4725-4733.
Simultaneous measurements of ambient gaseous species HNO2, HNO3, NH3 and particulate NO3- and NH4+ were carried out during 2002 in the city of Taichung, Taiwan. An annular denuder system (ADS) was used for the measurements. The annual mean concentrations of HNO2, HNO3, NH3, NO3- and NH4+ were 2.9, 1.9, 8.5, 6.0 and 4.6 mu g m(-3), respectively. Daily and seasonal patterns were observed. The concentration of HNO2 was found to be lower during the summer, whereas HNO3 and NH3 displayed higher concentrations. On the other hand, particulate NO3 exhibited significant seasonal variation with lower levels observed in autumn and summer. The average nitrogen conversion ratios (F,,) in the spring and summer were 21%, approximately 1.5 factor higher than those in the autumn and winter. Moreover, the photochemical reaction played an important role for the oxidation of NO2 to nitrate since F-n was well correlated with 03 during daytime in all seasons. During nighttime, F,, correlated well with relative humidity. These results suggest that the factors affecting nitrogen conversion ratio are different during daytime and nighttime. The present findings are compared with similar measurements worldwide, and the prevailing mechanisms are discussed. (c) 2006 Elsevier Ltd. All rights reserved.
ISSN: 1352-2310
DOI: 10.1016/j.atmosenv.2006.04.037
Appears in Collections:環境工程學系所

Show full item record

Google ScholarTM




Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.