| Summary: | 碩士 === 國立交通大學 === 環境工程研究所 === 83 === The sampling artifacts are formed due to the retention and
absorption of gases by sampling media and collected particles,
volatilization of collected particles, gas-particle and
particle-particle reactions within collected particles. Two
Annular Denuder Systems (ADS10 and ADS2.5) were used to quantify
sampling artifacts of soluble ionic species determined by the
high volume PM10 (Hi-vol PM10) and PM10 dichotomous (Dichot10 and
Dichot2.5) samplers. Artifact formation during 24-conditioning of
filter samples was important and was also investigated. In
addition, characteristics of acidic aerosols in Hsin Chu air
monitoring station was also studied.
Experimental results show that the PM10 dichotomous sampler
with Teflon filters collects 8 % more sulfate, because of
adsorption and oxidation of SO2 by the particle deposits, but
less nitrate (by 21 %), chloride (by 32 %) and ammonium (by 21 %)
than the ADS10 because of volatilization and reactions. While the
PM10 dichotomous sampler with Teflon filters collects nearly the
same amount of sulfate as the Hi-vol PM10 sampler with quartz
filters, it collects much less nitrate (by 8 %), chloride (by 8
%) and ammonium (by 3 %) than the latter because of more
volatilization and reactions in its fine fraction.
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