• 한국대기환경학회지
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• 제26권1호
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• pp.94-102
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• 2010

Water content of $PM_{2.5}$ (particles in the atmosphere with a diameter of less than or equal to a nominal $2.5{\mu}m$) was estimated by using a gas/aerosol equilibrium model, SCAPE2, for the particles collected at Seoul and Gosan, Korea. From measured and analyzed characteristics of the particles, the largest difference between Seoul and Gosan is the proportions of total ammonia (t-$NH_3$=gas phase $NH_3$+particle phase ${NH_4}^+$), total nitric acid (t-$HNO_3$=gas phase $HNO_3$+particle phase ${NO_3}^-$) and sulfuric acid ($H_2SO_4$). Even though both sites have sufficient t-$NH_3$ to neutralize acidic species such as $H_2SO_4$, t-$HNO_3$, and t-HCl (total chloric acid=gas phase HCl+particle phase $Cl^-$), equivalent fraction of t-$NH_3$ and t-$HNO_3$ are higher at Seoul and $H_2SO_4$ is higher at Gosan. Based on the modeling result, it is identified that the $PM_{2.5}$ at Seoul is more hygroscopic than Gosan if the meteorological conditions are the same. To reduce water content of $PM_{2.5}$, and thus, mass concentration, control measures for ammonia and nitrate reduction are needed for Seoul, and inter-governmental cooperation is required for Gosan.

• 대한치과기공학회지
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• 제20권1호
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• pp.139-143
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• 1998

This study was carried out to collect basic dates on fluoride intake from drinking water, and the apperance of mottled teeth after taking samples form 5 selected waterways from Iksan region's reservoir to the filtration plant for examination of the fluoride content. The results are as follows. 1. It indicatied that from Hoojung reservoir $2.17{\pm}0.95ppm$, Bulsan reservoir $1.93{\pm}0.23ppm$ and Yoolso reservoir $2.19{\pm}0.10ppm$. 2. Significances were found between Shinhung reservoir $2.57{\pm}1.22ppm$ and Uhwoo reservoir $0.80{\pm}0.55ppm$. 3. Except for the Uhwoo reservoir, the remaining 4 reservoir exceeded the standard fluoride content of 0.50-1.00ppm. For the residents in the region where they use natural water with fluoride content exceeding the standard 1.00ppm as their drinking water and the apperance of mottled teeth should be carried out.

• 한국환경과학회지
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• 제26권4호
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• pp.447-456
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• 2017

Chemical properties of aerosols were investigated by analyzing the inorganic water-soluble content in $PM_{2.5}$ collected in the downtown area of Jeju City in Jeju Island. Due to an increase in both the number of visiting tourists and the size of local population, the number of cars in this area is increasing, causing an increase in $PM_{2.5}$. Eight $PM_{2.5}$-bound major inorganic ions were analyzed during the summer and winter periods. The water-soluble inorganic component represents a significant fraction of $PM_{2.5}$. In particular, secondary inorganic aerosols contribute 36.2% and 47.5% of $PM_{2.5}$ mass in summer and winter, respectively. Nitrate concentrations increase for $[NH_4{^+}]/[SO_4{^{2-}}]$>1.5, and excess ammonium, which is necessary for ammonium nitrate formation, is linearly correlated with nitrate. These results are clearly observed during the winter because conditions are more conducive to the formation of ammonium nitrate. A significant negative correlation between Nitrogen Oxidation Ratio (NOR) and temperature was observed. The obtained results can be useful for a better understanding of the aerosol dynamics in the downtown area in Jeju City.

• 대한가정학회지
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• 제25권1호
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• pp.51-58
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• 1987

This study was undertaken to investigate changes in blood pressure and heart rate in normal cats by administration of Korean native green tea. The chemical components of Korean native green tea which determined are water(2.2%), water extract(32.7%), vitamin C(480%), caffeine(2.6%), tannin(32.7%) and amino acid of water soluble content 5.8%. Effect on blood pressure in administration 100mg/kg, 300mg/kg, 500mg/kg of extract of green tea, the mean depressor response is 44.8$\pm$3.3mmHg, 60.5$\pm$3.6mmHg, and 65.0$\pm$3.3mmHg in normal cats. Effect on heart rate in administration 100mg/kg, 300mg/kg of extract of Korean native green tea, the mean decreased heart rate is 2.8$\pm$4.5 beats/min, 15.2$\pm$6.4beats/min and 19.1$\pm$4.0 beats/min.

• 한국수산과학회지
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• 제44권3호
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• pp.237-242
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• 2011

To evaluate the proximate composition and main nutritive ingredients (vitamin A, $V_A$; vitamin E, $V_E$; cholesterol; the composition of fatty acids) between eels cultured in different domestic eel farms, we analyzed edible parts of eels that were cultured in three "Water Recirculation System (WRS)" farms and three "Still-Water System (SWS)" farms. We found differences in crude protein, crude lipids and the ash content of eel meat between the farms, but water content showed no significant difference. $V_A$ and $V_E$ contents did not show meaningful differences between the two culture methods, but there was a noticeable distinction between the eel farms. In particular, $V_E$ content showed significant differences between the eels of each farm (highest farm, about 25 mg/100 g dry wt; lowest farm, about 1 mg/100 g dry wt). The fatty acids of cultured eels were composed of monoenes (MUFA, 55-60%), saturates (SFA, 30-33%), $\omega$-6 highly unsaturates (HUFA, 1.6-2%) and $\omega$-3 HUFA (8-9.2%). The MUFA content of WRS eels ($59.9{\pm}1.97%$) was higher than that of SWS eels ($55.8{\pm}0.48%$). The contents of other fatty acids were higher in SWS eels (SFA, $33.0{\pm}0.52%$; $\omega$-6FUFA, $1.98{\pm}0.2%$; $\omega$-3 HUFA, $9.2{\pm}0.67%$) than in WRS eels (SFA, $30.5{\pm}1.34%$; $\omega$-6 HUFA, $1.62{\pm}0.19%$; $\omega$-3 HUFA, $8.0{\pm}0.5%$).

• 한국식품영양과학회지
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• 제2권1호
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• pp.55-59
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• 1973

닭고기의 가공특성(加工特性)을 알고, 가공방법(加工方法)을 개선(改善)하기 위하여 폐계와 육계(肉鷄)를 각(各) 20수(首)씩을 5군(群)으로 나누어(whole carcass, skinned carcass, debonned carcass, thigh muscle, breast muscle) 마쇄하여 실험(實驗)하였다. 그 결과를 요약(要約)하면 다음과 같다. 1. 폐계와 육계(肉鷄)의 도체률(屠體率)은 각(各) $64.32{\pm}2.11,\;67.96{\pm}1.16$이었고, 흡수증체률(吸水增體率)은 $105.43{\pm}1.9,\;104.13{\pm}0.2$이었다. 2. 화학성분(化學成分)은 육계(肉鷄)가 폐계보다 수분(水分)이 많고, 지방(脂肪)이 다소(多少) 적었다. 시료별(試料別)로는 폐계, 육계(肉鷄) 공(共)히 whole carcass ground meat가 thigh m., breast m보다 수분이 적고 지방과 회분의 많았다. 3. Relative WHC와 water retention은 thigh m. breast m. 과 skinned carcass가 높고, whole carcass가 가장 낮았다. 4. 가열감량률(加熱減量率)은 각군(各群) 모두 온도(溫度)가 상승할수록 높고 whole carcass가 가장 높았다. 5. Relative WHC, water retention과 가열감량률(加熱減量率)은 폐계와 육계(肉鷄) 사이의 유의성(有意性)은 전혀 인정(認定)되지 않았다.

• 한국대기환경학회지
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• 제20권6호
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• pp.803-810
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• 2004

Water contents in fine particles at Seoul and Gosan are estimated by using a gas/particle equilibrium model, SCAPE (Simulating Composition of Atmospheric Particles at Equilibrium). Also, sensitivity of particulate inorganic ionic concentrations on the total ionic species is estimated. Water content at Gosan is more sensitive to ambient relative humidity (RH) than Seoul. At both sites water content is most sensitive to sulfate concentration among sulfate, nitrate, and ammonium. Solid salts levels and compositions are also studied.

• 한국응용과학기술학회지
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• 제35권3호
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• pp.633-642
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• 2018

본 연구는 70 % 에탄올 추출물에서 추출한 Water Chestnut의 항산화, 항 염증 및 방부 효과를 평가하고자 하였다. RAW 264.7 세포를 사용하여 조사한 마름열매 추출물의 독성은 세포 생존율의 90 % 이상을 나타내었으며 폴리페놀 추출물의 총 함량은 $353.1{\pm}5.6mg/g$이었고 플라보노이드 총 함량은 $26.2{\pm}1.4mg/g$이었다. 항산화 활성을 확인하기 위한 1, 1-diphenyl-2-picryl-hydrazyl(DPPH) 라디컬 감소는 마름 열매 추출물 농도 $1{\sim}1000({\mu}g/m{\ell})$범위에서 각각 $17.0{\pm}2.8%{\sim}88.6{\pm}0.6%$의 감소효과를 보였고 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid(ABTS) 라디칼의 제거 범위는 각각 $2.3{\pm}0.8%{\sim}93.9{\pm}0.2%$ 였다. 활성 산소종 (ROS)에서의 효과는 1, 10, $100({\mu}g/m{\ell})$, $100{\mu}g/m{\ell}$ 농도에서 p <.01의 유의 한 감소를 보였다. 1, 10, $100({\mu}g/m{\ell})$ 농도의 Nitric Oxide (NO) 생성량을 측정 한 결과, 유의 한 (p <.001, p <.01)의 감소가 나타났다. 미생물에의 방부효과를 확인하기 위한 페이퍼 디스크를 사용하는 항 박테리아 기능과 페트리 필름을 사용하는 방부제 특성에 대해서는 유의한 효과가 나타나지 않았다.

• 한국식품저장유통학회지
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• 제9권2호
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• pp.154-160
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• 2002

박피 토란의 저장성을 향상시키기 위한 방안으로 전해산화수, 유자과즙을 첨가한 전해산화수 및 명반수를 사용하여 제조한 침지저장액에 따른 저장 효과를 살펴본 결과, 토란 수분함량은 80.05%에서 저장 25일째 수분의 흡수로 인해 82.12~84.24%로 다소 증가하였으나 처리구간의 차이는 거의 없었다. 색도는 전반적으로 L값은 감소하였으며 a, b값이 증가되는 현상을 보여주었으며, 조직감은 모든 처리구에서 초기 4,520$\pm$75 g에서 점차로 감소하는 경향을 보였으나 그 감소 폭이 유자과즙첨가구가 가장 적은 것으로 나타나 저장 25일째 4,160$\pm$80 g의 수준을 보였다. 총 vitamin C함량은 0.5%유자과즙 첨가 구에서 25일째 6.99 mg%로 약 57%의 보존율을 보여 가장 손실이 적었다. 총당은 대부분의 처리구에서 저장 15일째까지 급격히 하강하다가 저장 15일 이후에는 감소속도가 완만한 것을 볼 수 있었으며, 저장 중의 유리당의 함량은 저장기간에 따른 증감의 큰 변화 폭은 관찰할 수 없었다. 단지 sucrose 함량은 저장 중반기인 10일 전후에 일부 감소하다가 다시 증가하여 저장 25일째에는 처리구에 관계없이 저장 초기 값의 1.5~2배 수준에 도달하였으며, fructose, glucose, maltose는 저장기간별 처리구간에 따른 유의적인 차이가 나타나지 않았다. 박피 토란의 주 아미노산은 aspartic acid와glutamic acid로 각각 1,084.8 mg/100g. 691.8 mg/100g으로 나타났으며, 전해산화수에 침지하여 저장한 경우 aspartic acid 함량이 초기보다 13.9% 수준 증가하였다. 한편, 필수아미노산총량은 유자과즙 첨가구에 저장한 경우가 총당 감소율 측면에서 가장 유리한 것으로 나타났다.

• 혜화의학회지
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• 제23권1호
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• pp.105-114
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• 2014

Objectives : In this study, the antioxidant activities of the 80% ethanol and hot water extracts of Euphorbia supina Rafinesque were investigated. Methods : We measured total phenol contents, flavonoid contents, 2,2-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assay. The production of reactive oxygen species was measured in LPS-induced RAW 264.7 cells using flow cytometry system. Results : The content of phenol in the hot water extract was $65.529{\pm}0.462mg/g$ and $126.932{\pm}1.894mg/g$ in the 80% ethanol extract, and that of flavonoid in the hot water extract was $16.063{\pm}0.471mg/g$ and $29.159{\pm}1.963mg/g$ in the ethanol extract. The 80% ethanol extract also showed higher DPPH and ABTS radical scavenging activities ($90.8{\pm}1.0%$ and $92.5{\pm}0.7%$) than the hot water extract ($81.5{\pm}0.5%$ and $91.5{\pm}0.2%$). The production of reactive oxygen species(ROS) was reduced dose-dependently by 80% ethanol and hot water extract at concentration of 1, 10 and $100{\mu}g/m{\ell}$ of RAW 264.7 cells. Conclusion : According to these results, the 80% ethanol extract of Euphorbia supina Rafinesque has a good anti-oxidative effects than the hot water extract. Thus, the 80% ethanol extract of Euphorbia supina Rafinesque may serve as useful natural antioxidants.