• Journal of Korean Society for Atmospheric Environment
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• v.27 no.5
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• pp.603-613
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• 2011

The collection of $PM_{10}$ and $PM_{2.5}$ samples was made at Gosan site of Jeju Island. Their ionic compositions of both inorganic and organic phases were then analyzed to examine their acidification and neutralization characteristics in atmospheric aerosols. The mass concentrations of $PM_{10}$ and $PM_{2.5}$ at Gosan site were $37.6{\pm}20.1$ and $22.9{\pm}14.3{\mu}g/m^3$, respectively, showing the content ratio of $PM_{2.5}$ to $PM_{10}$ as 61.0%. In the evaluation of ionic balance, the correlation coefficients (r) between the sums of cationic and anionic equivalent concentrations were excellent with 0.982 ($PM_{10}$) and 0.991 ($PM_{2.5}$). The concentration ratios of $PM_{2.5}/PM_{10}$ derived for nss-$SO_4^{2-}$, $NO_3^-$, and $NH_4^+$ were 0.94, 0.56, and 1.02, respectively, indicating the relative dominance of fine fractions. The acidifying capacity of inorganic anions ($SO_4^{2-}$ and $NO_3^-$) in $PM_{10}$ and $PM_{2.5}$ were 96.5% and 97.3%, while those of organic anions ($HCOO^-$ and $CH_3COO^-$) in each fraction were 2.9% and 2.0%, respectively. On the other hand, the neutralizing capacity of $PM_{10}$ and $PM_{2.5}$ by $NH_3$ were 72.8% and 82.3%, while their $CaCO_3$ counter parts were 22.5% and 13.3%, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.2
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• pp.121-127
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• 1992

This study was carried out to investigate the features of air pollutants in rainwater and trace their transported trajectories from other countries. Chemical analysis data of rainwater and suspended particulates collected at Seoul, Kanghwa, and Taean for three years were used to evaluate the effects of long-range transport of air pollutants. Scavenging theory on washout and rainout effect during a rainy period was applied to estimate whether pollutants in the precipitation were long-range transported or not. On the other hand, precipitation weighted surface wind were evaluated to analyze the effect from local sources on atmospheric concentrations. As a result, contribution of air pollutants caused by anthropogenic sources in the precipitation which was identified to be long range transported was confirmed significantly high and trajectory of these pollutants was to be equivalent to 850mb isobar. Although concentration of acidifying components increased in the precipitation, neutralization by alkaline soil components such as $Ca^{2+}$ and $Mg^{2+}$ was conspicuous especially during Yellow-sand period.

• Journal of Environmental Health Sciences
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• v.22 no.4
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• pp.62-68
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• 1996

Precipitation samples were collected by the wet-only event sampling method at Seoul from September 1991 to April 1995. Concentrations of samples for the ion components($NO_3^-, NO_2^-, SO_4^{2-}, Cl^-, F^-, Na^+, K^+, Ca^{2+}, Mg^{2+}$ and $NH_4^+$) were measured in addition to pH and electric conductivity. During the sampling period, 182 samples were collected, but only 163 samples were identified as valid. The pH, calculated from the volume-weighted $H^+$ concentration, was found to be 4.7, indicating a relatively intensive acidity compared with data from other regions of the world, where acid deposition was known to be a problem. Above all, the concentration of non-seasalt sulfate was $84 \mu eq/L$, which was the highest compared to that measured in other regions of the world. The major acidifying ions in the precipitation at Seoul were identified as sulfate and nitrate except for chloride, because the Cl/Na ratio in the precipitation was close to the ratio in seawater. If all of the non-seasalt sulfate and nitrate existed in the form of sulfuric and nitric acids, respectively, the average pH in the precipitation was calculated as 3.7, lower than the measured value. Consequently, the difference between the calculated and measured pH suggest that the acidity of precipitation was neutralized by alkaline species, not due to the low contribution of an anthropogenic air pollutants to the precipitation. The equivalent concentration ratio of sulfate to nitrate was 3.5, which indicated that the contributions of sulfuric and nitric acids to the precipitation acidity were 78% and 22%, respectively.