• Journal of Korean Society for Atmospheric Environment
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• v.32 no.1
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• pp.100-113
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• 2016

In this study, the characteristics of $PM_{2.5}$ and $PM_{2.5-10}$ concentrations were identified in two different functional areas including Chuncheon and Youngwol, Korea. Even though the anthropogenic emission rates of $PM_{2.5}$ and $PM_{10}$ are approximately four times higher in Youngwol than in Chuncheon their atmospheric concentrations were statistically higher in Chuncheon. In Chuncheon, both $PM_{2.5}$ concentrations and the ratio of $PM_{2.5}/PM_{10}$ increased as relative humidity (RH) increased possibly because the inorganic and/or organic secondary aerosols were actively formed at high RH. This result was also supported by that $PM_{2.5}$ concentration was enhanced under the fog and mist conditions in Chuncheon. On the other hand, both $PM_{2.5}$ and $PM_{2.5-10}$ concentrations clearly increased with the southerly winds blown from the cement production facility in Youngwol. In addition, high $PM_{2.5-10}$ concentrations were observed with high wind speed, low relative humidity, and high $NO_2$ concentrations in Youngwol, suggesting that $PM_{2.5-10}$ was generated through the physical process including crushing and packing procedures followed by resuspension from cement and lime factory.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.627-641
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• 2006

Atmospheric $PM_{2.5}$ and $PM_{10}$ were measured to investigate their levels and water-soluble ions(${SO_4}^{2-},\;{NO_3}^-,\;{NO_2}^-,\;Cl^-,\;{NH_4}^+,\;Na^+,\;Ca^{2+},\;Mg^{2+},\;and\;K^+$) in Daegu between February 17 and April 18, 2006. Four Asian dust episodes during the period were examined for the influence of Asian dust on the particulate properties. Daily $PM_{2.5}\;and\;PM_{2.5-10}$ concentrations ranged between $10.83{\sim}136.76{\mu}g/m^3$ with a mean of $38.43{\mu}g/m^3$ and $16.13{\sim}409.13{\mu}g/m^3$ with a mean of $79.98{\mu}g/m^3$, respectively. For all measured ions the mean fractions of $PM_{2.5}\;and\;PM_{2.5-10}$ were 51.8% and 28.9% being lowered to 30.7% and 9.4%, respectively, during the dust episodes. Secondary ions (i.e., non-sea salt ${SO_4}^{2-},\;{NO_3}^-,\;and\;{NH_4}^+$) contributed 44.3% and 14.8% to $PM_{2.5}\;and\;PM_{2.5-10}$, respectively, with a decreased contribution during the episodes. The average equivalent ratio of ${NH_4}^+$ to the sum of ${SO_4}^{2-}\;and\;{NO_3}^-$ was 0.99 and 0.89 for $PM_{2.5}\;and\;PM_{2.5-10}$, respectively, indicating high source strength of $NH_3$ and its dominance in the neutralization of the acidic ions. Correlations and charge balance between ions suggest that neutralization of the acidic ions results in substantial depletions of carbonate both in $PM_{2.5}\;and\;PM_{2.5-10}$ and chloride only in $PM_{2.5}$.

• Journal of Environmental Science International
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• v.28 no.7
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• pp.581-594
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• 2019

This research investigated the characteristics of $PM_{10}$ and $PM_{2.5}$ concentrations at the main subway stations in Busan. Annual mean $PM_{10}$ concentrations at the Seomyeon 1- waiting room and platform were $51.3{\mu}g/m^3$ and $47.5{\mu}g/m^3$, respectively, and the annual $PM_{2.5}$ concentration at the Seomyeon 1- platform was $28.8{\mu}g/m^3$. $PM_{2.5}$/$PM_{10}$ ratio at Seomyeon 1-platform and Dongnae station were 0.58 and 0.53, respectively. Diurnal variation of $PM_{10}$ concentration at subway stations in Busan was categorized into four types, depending on the number of peaks and the times at which the peaks occurred. Unlike the areas outside of the subway stations which reported maximum $PM_{10}$ concentration mostly in spring across the entire locations, the interiors of the subway stations reported the maximum $PM_{10}$ concentration in spring, winter, and even summer, depending on their location. $PM_{10}$ concentration was highest on Saturday and lowest on Sunday. The numbers of days when $PM_{10}$ concentration exceeded $100{\mu}g/m^3$ and $80{\mu}g/m^3$ per day over the last three years at the subway stations in Busan were 36 and 239, respectively. The findings of this research are expected to enhace the understanding of the fine particle characteristics at subway stations in Busan and be useful for developing a strategy for controlling urban indoor air quality.

• Korean Journal of Animal Reproduction
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• v.24 no.3
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• pp.231-239
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• 2000

In this study, we observed the effects of dioxin on weights of body, testes and other organs, the number and motility of sperm in the a various dose after two days' of administration in mice. Animals were treated with oral dose of dioxin 10, 20, 30, 40 mg/kg body weight, respectively. 1, After administration dioxin at doses of 10, 20, 30 and 40 $\mu\textrm{g}$/kg to the mice, the changes in body weights were 30.6 $\pm$ 2.g~40.7 $\pm$ 3.9g and 30.8 $\pm$4.1g~39.5g $\pm$3.1 for 10 and 20 $\mu\textrm{g}$/kg dosed group, 31.0 $\pm$ 3.5g ~ 39.0 $\pm$ 3.5g, 30.6 $\pm$ 3.4g~38.3 $\pm$ 4.0g for 30 and 40 $\mu\textrm{g}$/kg dosed group. The body weight of dioxin-administered group showed lower value when compared to 30.6 $\pm$ 2.8g ~ 44.5 $\pm$ 3.1g of which is control group's. 2. After administration of dioxin at doses of 10, 20, 30 and 40 $\mu\textrm{g}$/kg to the mice, the increase in the number of WBC was prominent, but the increase in the number of RBC wasn't significant, though the values of Hb, PCV, and PLT were higher than those of control group's. 3. After administration of dioxin at doses of 10. 20, 30 and 40 $\mu\textrm{g}$/kg to the mice, the changes in sperm number were 112.5 $\pm$ 3.7~119.4 $\pm$4.2 $\times$ 10$^{6}$ $m\ell$, 103.9 $\pm$3.8 ~ 110.2 $\pm$ 3.6 $\times$ 10$^{6}$ $m\ell$, 97.5 $\pm$ 3.4 ~105.7 $\pm$ 4.4 $\times$ 10$^{6}$ $m\ell$, 87.2 $\pm$ 3.7~98.5 $\pm$ 3.8 $\times$ 10$^{6}$ $m\ell$, respectively. The sperm number of dioxin-administered group showed lower value than that of control group's, which was 119.0 $\pm$ 4.3 ~ 120.7 $\pm$ 4.8 $\times$ 10$^{6}$ $m\ell$. After administration of dioxin at doses of 10~40 $\mu\textrm{g}$/kg to the mice, the sperm motility were 69.4$\pm$ 3.0 ~ 86.6 $\pm$4.7%. The sperm motility of dioxin-administered group showed lower value than that of control group's. 4. After administration of dioxin at doses of 10, 20, 30 and 40$\mu\textrm{g}$/kg to the mice, the organ weight of each dioxin-administered group's was decreased a little compared to that of control group's. 5. After administration of dioxin at doses of 10, 20, 30 and 40 $\mu\textrm{g}$/kg to the mice, the weights of spleen, kidneys, and liver showed increase a little.

• Journal of Environmental Health Sciences
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• v.34 no.1
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• pp.34-41
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• 2008

The objective of this study is to provide the research data on the actual concentrations of $PM_{10},\;PM_{2.5},\;PM_1\;and\;CO_2$ in Seoul subway carriages. Mean concentrations of $PM_{10},\;PM_{2.5}\;and\;PM_1,\;and\;CO_2$ in subway carriages were investigated at levels of $215.1{\pm}101.4{\mu}g/m^3,\;86.9{\pm}38.6{\mu}g/m^3,\;27.0{\pm}11.4{\mu}g/m^3,\;and\;1,588{\pm}714ppm$, respectively. The mean concentrations in subway carriages were higher when the train ran on an underground track rather than on an above ground track. The measured concentration of particulate matter varied with the time of day and was highest in the morning, followed by noon and evening while the $CO_2$ concentration was highest in the morning, followed by evening and noon. In relation to correlation among the pollutants: the correlation between $PM_{10}\;and\;PM_{2.5}$ was 0.92, and that between $PM_{2.5}\;and\;PM_1$ was 0.94. The inclusion rate of $PM_{2.5}\;to\;PM_{10}$ was $41{\pm}7%$ and that of $PM_1\;to\;PM_{2.5}\;was\;32{\pm}4%$. In addition, the $CO_2$ concentration had a positive relation with the number of people in a carriage, whereas the concentration of $PM_{10}$ had negative correlation to the number of people. In relation to these two pollutants we calculated using a regression equation (34.06+0.04$CO_2$(ppm)-0.09 PM10$({\mu}g/m^3)$($R^2$=0.30, p<0.01, n=707), that a maximum number of 61 persons would ensure that each pollutant is maintained below the criteria level, applicable to subway stations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.259-267
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• 2020

This study measured the Particulate Matter (PM) concentration according to altitude (30 m, 60 m, 90 m, 120 m, and 150 m) in three different environments: a construction site, natural environment (arboretum), and residential area. PM_2.5 and PM₁₀ values at 30 m above the construction site were 18.63 ㎍/㎥ and 24.23 ㎍/㎥ while values at 150 m were 10.89 ㎍/㎥ and 10.61 ㎍/㎥, respectively, indicating the average concentration decreased as altitude increased. PM_2.5 and PM₁₀ values at 30 m above the natural environment were 9.03 ㎍/㎥ and 11.21 ㎍/㎥ while those at 150 m were 3.42 ㎍/㎥ and 3.57 ㎍/㎥, respectively, showing lower average concentrations as altitude increased. PM_2.5 and PM₁₀ values at 30 m above the residential area were 10.65 ㎍/㎥ and 12.06 ㎍/㎥ while those at 150 m were 4.24 ㎍/㎥ and 5.17 ㎍/㎥, also demonstrating lower PM concentrations as altitude increased. The PM concentrations decreased as altitude increased at all tested sites and also decreased between environments in the following order: construction site, residential area, and natural environment. The results of this study are significant because PM concentrations were measured at various altitudes at different land-use sites. The results are expected to serve as basic data for decision-making in both regional and urban planning.

• Journal of Environmental Health Sciences
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• v.36 no.2
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• pp.108-117
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• 2010

In this study, ambient particulate matter ($PM_{2.5}$ and $PM_{10}$) levels were measured and their chemical and physical properties were characterized. Two sites in Gwangju were sampled once a month from December 2008 to November 2009. The annual mean concentrations of $PM_{2.5}$ and $PM_{10}$ were $26.9\;{\mu}g/m^3$ and $46.3\;{\mu}g/m^3$, respectively, in Nongseongdong and $26.1\;{\mu}g/m^3$ and $44.8\;{\mu}g/m^3$, respectively, in Duam-dong. $PM_{2.5}$ levels were 1.8 times higher than the USA Environmental Protection Agency (EPA) national ambient air quality standard for $PM_{2.5}$ ($15\;{\mu}g/m^3$). The average $PM_{2.5}/PM_{10}$ ratio of 0.58 suggested that $PM_{2.5}$ is a significant component of the ambient particle pollution. The order of concentration of metallic elements in $PM_{2.5}$ and $PM_{10}$ was Si > Al > Fe > Zn > Pb > Cu > Mn. Cd was not detected. The earth crustal enrichment factors for Cr, Cu, Pb and Zn in $PM_{2.5}$ were higher than those in $PM_{10}$. When the earth crustal enrichment factors for Cr, Cu, Pb and Zn were higher than 10, this suggested influence from anthropogenic sources. The soil contribution ratios for $PM_{2.5}$ and $PM_{10}$ were 11.3% and 16.4%, respectively, and were higher in the fall and winter. Anions (${SO_4}^{-2}$, ${NO_3}^-$, and $Cl^-$) comprise 28.7% of $PM_{2.5}$ and 21.4% of $PM_{10}$. The correlation coefficient of Zn-Fe, Mn-Cu, Fe-Cu and Fe-Mn in $PM_{2.5}$ was high in the sampling sites, and metallic elements were primarily from anthropogenic sources such as fuel combustion and vehicle emissions.

• Journal of the Korean earth science society
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• v.23 no.6
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• pp.514-525
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• 2002

The analysis of heavy metals associated with both PM2.5 and PM10 fraction of aerosols was made from a northeast region of Seoul during the spring period of 2001. The mean concentrations of fine (PM2.5), coarse (PM10-PM2.5), and PM10 fraction were observed as 49.3${\pm}$29.2, 50.5${\pm}$35.0, and 95.5${\pm}$46.1 ${\mu}g$/m$^3$, respectively during this study period. According to the results of enrichment factor (EF) analysis between different particle fractions, major elements (including Fe, Ca, Na, and K) were found to exhibit EF values of less than 10. However, heavy metal components (like Zn and Pb) showed very high EF values. Comparison of fine/coarse (F/C) concentration ratio showed that Zn, Cr, Pb, and Ni have higher ratio values than others. The metallic composition of particles was also compared on both absolute and relative terms. The results of our analysis showed an evidence that the increase in the total metallic contents is prominent during the spring period due mostly to the Asian Dust event.

• The Korean Journal of Nuclear Medicine
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• v.6 no.1
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• pp.41-49
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• 1972

The author observed the thyroid $^{131}I$ uptake rate using an intradermal injection method. The amount of activity remaining at the site of intradermal injection of 0.1 ml. of $5{\mu}Ci.\;of\;^{131}I$ in physiologic saline was measured in 79 cases of hyperthyroidism and in 24 cases of hypothyroidism. The cases had been confirmed by clinical and laboratory findings, at the department of medicine, (radioisotope clinic) Pusan National University Hospital. Twenty-nine normal control cases were examined currently by the same technique during the period from Jan. 1967 to June 1970. The following results were obtained: 1. In the normal group, the ranges and mean values of the thyroid uptake 10, 15, 20, 25, 30 and 60 minutes after intradermal $^{131}I$ injection, were $0{\sim}10%(6.33{\pm}1.63),\;0{\sim}15%(7.83{\pm}2.12),\;0{\sim}15%(8.46{\pm}2.82),\;5.1{\sim}20%(9.66{\pm}2.27),\;5.1{\sim}25%(10.47{\pm}2.52),\;5.1{\sim}30%(13.03{\pm}4.42)$. 2. In the hyperthyroid group, the ranges and mean values of the thyroid uptake 10, 15, 20, 25, 30 and 60 minutes after intradermal $^{131}I$ injection were $5.1{\sim}45%(22.25{\pm}7.04),\;10.1{\sim}50%(28.32{\pm}6.67),\;15.1{\sim}55%(34.78{\pm}11.63),\;15.1{\sim}65%(37.95{\pm}7.72),\;20.1{\sim}65%(41.49{\pm}0.05)\;and\;20.18096(48.71{\pm}12.51)$. 3. In the hypothyroid group, he ranges of thyroid $^{131}I$ uptake by intradermal $^{131}I$ injection at 10, 15, 20, 25, 30 and 60 minutes lay between 0 and 10%, and the the mean values were $4.23{\pm}1.76,\;5.08{\pm}1.68,\;5.56{\pm}1.70,\;6.02{\pm}1.75,\;6.37{\pm}1.91\;and\;6.95{\pm}2.07$. 4. In conclusion, thyroid function test using an intradermal injection method in cases of hyperthyroidism, showed characteristic values which seemed to be of diagnostic significance.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.1
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• pp.132-140
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• 2007

Concentrations of atmospheric fine particles in Chungnam were measured at 7 sampling sites during 2005. The daily average concentrations of PM 10, PM2.5, and PM1 ranged from 14.9 to $136.5{\mu}g/m^3$, 8.2 to $113.2{\mu}g/m^3$, and 5.7 to $107.5{\mu}g/m^3$, respectively, and the highest levels were observed at Yeongi site. The lowest concentrations for the all size fractions of particulate were observed at Taean located at the west end of the peninsula. The daily average PM10 concentrations were below the current National Standard at all sites, while the daily average PM2.5 concentrations frequently exceeded the US Standard at Cheonan, Dangjin, Boryeong, and Yeongi sites. The frequencies of PM2.5 concentrations exceeding the US standard at Cheonan, Dangjin, Boryeong, and Yeongi were 10.8%, 6.7%, 6.7%, and 26.7%, respectively. In addition, $68{\sim}80%$ of PM10 was in the PM2.5 fraction indicating that fine particles were the major component of atmospheric particles in Chungnam.