| Summary: | 碩士 === 輔英科技大學 === 環境工程與科學系碩士班 === 99 === Abstract
The monitoring data from 2006 to 2010 of EPA’s particulate super-station in southern Taiwan-Fooyin University core station was used to analyze the chemical characteristics of atmospheric particulates. The analytical methods were classified the high concentrations of episode days and non-episode days.
The analytical results showed that the concentration of PM10 and PM2.5 were about 23~68 μgm-3 and 15~45 μgm-3, respectively. The trends of PM10, PM2.5 and the other chemical compositions of nitrate, sulfate, OC and EC presented the low concentration in summer and the high concentration in winter, respectively. The reasons might be the high atmospheric pressure and monsoon from the mainland, and they caused the phenomenon of high particulate concentration in winter. Besides, CO often has the high concentration in winter. The phenomenon showed that the weather conditions caused the poor transportation and the particulate accumulation.
PM10, PM2.5 and the other chemical compositions of nitrate, sulfate, OC and EC had the peak concentrations in the morning. The reasons should be the mobile sources and poor transportation, they caused the high concentration of accumulated pollutants. Besides, PM10, PM2.5, OC and sulfate had the peaks at noon in summer. The reasons should be the strong photochemical reaction and external contaminant accumulaion, and they caused the high concentration of secondary pollutants.
Nitrate and sulfate concentrations often decrease significantly in the afternoon. The reasons might be the lack of precursor’s reactions through NH3, NOX and NOy. The results of secondary organic carbon showed that secondary organic carbon was the main pollutant at the episode and non-episode days except winter. The ratios of second organic carbon and total organic carbon were highest at the episode days in summer and autumn, the ranges were 67.62~71.38% and 73.73~75.81%, respectively. Besides, the ratios of second organic carbon and total organic carbon at night time were higher than those of day time at the episode and non-episode days. The weather conditions of low wind speed or low temperature favor the production of secondary organic carbon.
Keywords: particulate, supersite, secondary organic carbon, OC, EC.
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