| Summary: | 碩士 === 國立清華大學 === 原子科學系 === 89 === Abstract
This research presents measurement of 56 NMHCs monitored from ambient air by near time sampling at 20 locations from 7 p.m. to 9 p.m. in each season of year 2000 ( 20 samples per season). A 16-canister automatic introducing system was applied to inject the air sample into a sample preconcentration trap (SPT), which cryofocused the sample. After desorbed from SPT (by heating to 1600C), the sample was introduced into and analyzed by a Varian 3800 gas chromatography (GC) system coupled with flame ionization detection (FID) or mass-selection detection (MSD).
From the four-season measurements, the most abundant NMHCs in Kaohsiung were found to be ethylene and toluene. The concentrations of ethylene and toluene were poorly correlated (R2 =0.111 to 0.458). while a better correlation existed between concentrations of toluene and m/p-xylene (R2 =0.672 to 0.817).
From comparison between the concentration of ethylene and ethylene/toluene ratio, the major source of these specific pollutants could be identified. The results suggested that toluene was primarily from the emissions of mobile vehicles and partly from vaporization of organic solvents used in petroleum and hi-tech industries, while ethylene was emitted mainly from petroleum plants and, to a lesser level, vehicles. With the combination of data collected from the 20 different sites, a preliminary knowledge about the distribution and sources pollutants could be obtained (alkane =34.2%, alkene=23.8%, alkyne=4.5%, aromatic=34.5%).
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