• 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 the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4940-4950
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• 2011

cis-(3R,5R)-Atorvastatin Ca (1) used for hyperlipidemia have four stereomers. However, It is very difficult to prepare stereoselective stereomers. In this paper, the reduction of 3,5-diketo atorvastatin ester (3) was performed using $Me_4NHB(OAc)_3$ in acetic acid as a reductant and showed excellent stereoselectivity in the double reduction of 3,5-diketo atorvastatin ester (3). As a result, reduction of compound 3 by $Me_4NHB(OAc)_3$ was purely obtained with cis-(3R,5R)-atorvastatin ester (4) of 1.5% and trans-(3R,5S)-atorvastatin ester (5) of 98.5%. Also, cis-(3R,5R)-atorvastatin Ca (1) and trans-(3R,5S)-atorvastatin Ca (7) were used to determine efficacy in the treatment of liver damage and hyperlipidemia induced by a high-fat diet in rats and to study the performance of the January 2010 experient was conducted. As a result, total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-c), low-density lipoprotein-cholesterol (LDL-c), and triglyceride (TG) levels of compound 1 and 7 groups were $93.0{\pm}0.5$, $43.5{\pm}0.8$, $40.4{\pm}1.4$, $45.6{\pm}0.9\;mg/d{\ell}$ and $110.0{\pm}0.7$, $33.3{\pm}0.6$, $65.8{\pm}1.9$, $54.8{\pm}1.2\;mg/d{\ell}$, respectively. Atherogenic index (AI) and cardiac risk factor (CRF) in compound 1 and 7 were $1.14{\pm}0.05$, $2.14{\pm}0.05$ and $2.31{\pm}0.06$, $3.31{\pm}0.06$, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were $51.9{\pm}4.6$, $16.0{\pm}2.1\;IU/{\ell}$ and $75.8{\pm}4.4$, $35.1{\pm}9.7\;IU/{\ell}$. Taken together, while compound 1 treat against high-fat diet-induced hyperlipidemia by attenuating hepatic lipid depots and reducing oxidative stress, compound 7 group had a low curative effect on hyperlipidemia induced by a high-fat diet in rats. These findings suggest that new method about synthesis of stereoselective stereomers and indicate that it may consider using in a clinical trial.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.6
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• pp.682-692
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• 2008

Fine particles ($PM_{2.5}$) were collected and analyzed from November 2005 through August 2007 in Chuncheon, Korea to investigate the characteristics of $PM_{2.5}$ and its ionic constituents. The average $PM_{2.5}$ concentration during the study period was $39{\mu}g/m^3$, which is almost two times higher than the annual US NAAQS $PM_{2.5}$ standard of $15{\mu}g/m^3$. $PM_{2.5}$ concentrations were higher in spring and winter than in summer and fall. During spring, Asian Dust events dramatically enhanced $PM_{2.5}$ concentrations, and long-range transport of $PM_{2.5}$ emitted in industrial area of China often occurred during winter based on trajectory analysis. Contribution of $PM_{2.5}$ to $PM_{10}$ concentrations ranged from $72{\mu}g/m^3$ during Asian Dust events to $457{\mu}g/m^3$, indicating that a large portion of $PM_{2.5{\sim}10}$ was transported from China during Asian Dust events. Among the major ionic constituents ${SO_4}^{2-}$ showed the highest concentration, followed by ${NH_4}^+$, ${NO_3}^-$ and ${NO_2}^-$. Chuncheon appeared to be ${NH_4}^+$ rich environment, indicating that $(NH_4)_{2}SO_4$ and ${NH_4}{NO_3}$ were the predominant forms of ${NO_3}^-$ and ${SO_4}^2$ in $PM_{2.5}$. Haze has frequently occurred in Chuncheon since So-Yang dam was constructed in 1973. Haze events were observed on 23 days during sampling period, and the average $PM_{2.5}$ concentration was approximately 1.6 times higher during haze events than during non-haze events. This result suggests that haze enhances the secondary aerosol formation because the aerosol spontaneously absorbs water to form a saturated salt solution, deriving a significant increase in the mass of the particle.

• 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 Environmental Science International
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• v.25 no.5
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• pp.727-736
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• 2016

The ambient mass concentration and chemical composition of the $PM_{2.5}$ were determined at the highland site with 1,100 m above sea level on Jeju Island from June 2013 to November 2014. Yearly averaged mass concentration of $PM_{2.5}$ was $11.97{\pm}8.63{\mu}g/m^3$. $PM_{2.5}$ concentrations were highest during the spring, while they tended to be lowest during the summer. Eight water soluble ionic species attributed 45.5% to $PM_{2.5}$ mass. $SO{_4}^{2-}$, $NO_3{^-}$ and $NH_4{^+}$ were major ions, which occupied to 27.9%, 3.7% and 12.3%, respectively. The greatest contributors to total mass concentration of water-soluble ions contained in $PM_{2.5}$ were sulfate, ammonium and nitrate. These three ions accounted for 96.6% in total ions mass concentration of $PM_{2.5}$. We could infer that these three secondary ions exist mostly in the form of $(NH_4)_2SO_4$ and $NH_4NO_3$. $Ca^{2+}$ and $Mg^{2+}$ had a good relationship and with r=0.9. The molar ratio of $Mg^{2+}/Ca^{2+}$ in this study was lower than the value observed in sea water and higher than that in soil dust, indicating that these two ions originated from other sources rather than ocean and soil dust in this study.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.5
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• pp.419-426
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• 2002

The concentrations of three different fractions of particulate matters including PM2.5, PM10, and TSP were compared between the Asian Dust (AD) and non-AD (NAD) periods during the spring season of 2001. For the purpose of this comparative analysis, the data sets were obtained from four different observatory sites located within the city boundary of Seoul that concurrently measure those three fractions of PM at hourly intervals. According to our study, several conclusions can be drawn to describe relationships between the AD event and PM distribution characteristics. First of all, it is apparent that the concentrations of PM are distinctively distinguished between AD and NAD. If the extent of contribution to the AD events are assessed on the quantitative basis, it appears that their magnitude increases on the order of PM2.5, PM10, and TSP. As a result, the increase of PM observed during AD event is dominated by the coarse rather than fine fraction of PM. Moreover, when their relationships were assessed in terms of fractional ratios, it was found that TSP/PM10 ratios were almost constant, regardless of the occurrences of AD. On the other hand, the coarse/fine or TSP/PM2.5 ratios changed dramatically between AD and NAD periods. The results of our analysis cleary distinguishes quantitative role of each PM fraction between AD and NAD period, while suggesting indirectly the possible control of source processes on such relationships.

• 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.16 no.5
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• pp.477-485
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• 2000

The data set was collected on fifty-eight different days with a 24-h sampling period from October 27, 1995 through August 25, 1996. From the chemical mass balance (CMB) analysis of $PM_{2.5}$ in the Chongju area, the contributions from soil, gasoline, diesel, light and heavy oil combustion were 2.6%, 15.4%, 9.0%, 28.8% and 1.5%, respectively. Residual $NO_{3}^{-}$), residual $SO_{4}^{2-}$ and residual OC, possibly formed in the atmosphere. represented additional 8.0, 10.2, and 1.6% of the $PM_{2.5}$, respectively. Other unidentified sources constituted the remaining 22.9%. From the CMB analysis, the $PM_{2.5}$ source contribution for fall, winter, spring and summer were 92, 76.8, 77.5 and 59.2%, respectively.

• Journal of Environmental Science International
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• v.27 no.7
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• pp.597-610
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• 2018

This study observed particulate matter ($PM_{2.5}$ and $PM_{10}$) in the downtown area of Jeju City, South Korea, to understand the chemical composition of particulates based on an analysis of the water-soluble ionic species contained in the particles. The mass fraction of the ionic species in the sampled $PM_{10}$ and $PM_{2.5}$ was 44.3% and 42.2%, respectively. In contrast, in Daegu City and Suwon City, the mass fraction of the ionic species in $PM_{2.5}$ was higher than that in $PM_{10}$. The chloride depletion percentage of $PM_{10}$ and $PM_{2.5}$ in Jeju City was higher than 61% and 66%, respectively. The contribution of sea-salt to the mass of $PM_{10}$ (5.9%) and $PM_{2.5}$ (2.6%) in Jeju City was similar to that in several coastal regions of South Korea. The mass ratio of $Cl^-$ to $Na^+$ in the downtown area of Jeju City was comparable to that in some coastal regions, such as the Gosan Area of Jeju Island, Deokjeok Island, and Taean City. The mass fraction of sea-salt in $PM_{10}$ and $PM_{2.5}$ was very low, and the concentration of sodium and chloride ions in $PM_{10}$ was not correlated with those in $PM_{2.5}$ ($R^2$ < 0.2), suggesting that the effects of sea-salt on the formation of particulate matter in Jeju City might be insignificant. The relationship between $NH_4{^+}$ and several anions such as $SO_4{^{2-}}$, $NO_3{^-}$, and $Cl^-$, as well as the relationship between the measurement and calculation of ammonium ion concentration, suggested that sea-salts may not react with $H_2SO_4$, and $(NH_4)_2SO_4$ may be a major secondary inorganic aerosol component of $PM_{2.5}$ and $PM_{10}$ in Jeju City.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.3
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• pp.406-417
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• 2018

In this study, $PM_{2.5}$ samples were collected during approximately 3 years in Chuncheon, a small residential and tourist city, in Korea. The average $PM_{2.5}$ concentration was $26.9{\mu}g/m^3$, exceeding the annual national air quality standard. $PM_{2.5}$ showed typical seasonal variation, having higher concentration in winter and lower concentration in summer. Sixteen metallic elements in $PM_{2.5}$ were also analyzed, and K was the highest contributor especially in late fall and winter. In addition, K considerably increased for the top 10% of $PM_{2.5}$ samples and showed the highest correlation coefficient with $PM_{2.5}$ among all other metallic elements. These results suggest that the combustion of agricultural residue and other biomass, the major source of K was likely to be important to high $PM_{2.5}$ concentration events in this city. Crustal elements including Al, Fe, Si, Ti, Mg showed high concentration in spring while Cr, Cu and Ni were relatively consistent throughout a year. Principal component analysis was used to trace the sources, and soil re-suspension, combustion of biomass and fossil fuels, and asphalt concrete production were identified as the main sources of $PM_{2.5}$.