• 한국환경보건학회지
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• 제7권2호
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• pp.89-95
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• 1981

A Continuous monitoring of Air Pollution in city of Seoul was carried out from January 1 to December 31 of 1979 at two selected sites, Kwanghwamun observatory and Kwanag observatory. The measured data were averaged on monthly basis. The maximun value of oxidant pollution was observed in July, and the minimum in February. It is the purpose of this study to determine the effect of hydrocarbon, nitrogenoxide, wind velocity and ambient temprature on the observed values of oxidant pollution for the above two months. The results of the study may be summarized as follows. 1) The oxidant concentration in February was higher than in July by about 2 times in both downtown area and the suburbia. The concentration in downtown area was $25.75\pm 4.75ppb$, and that in suburbia was $29.83\pm 5.16ppb$. As for the oxidant concentration in July, it was observed that the suburban area ($26.464\pm 7.59ppb$) had about 2.8 times higher value than the downtown area ($9.284\pm 1.55ppb$). 2) The peak oxidant concentration of suburban area during the daytime is occured from noon to 5:00 P.M.. These patterns are similar to the classical patterns, but the peak Oxidant Concentration of downtown area in February was occured at 9:00A.M. 3) The overall level of nitrogen oxide pollution was much higher in downtown area than in suburban area. Two peaks of nitrogen oxide concentration occured at 10 A.M. and 12 midnight in downtown area. This observation agrees with the report that the air pollution is higher in the area where the pollution sources are concentrated. 4) The multiple correlation analysis for the oxidant and the other variables measured in February in downtown area showed close correlation with nitrogen oxide and ambient temprature. The multiple correlation coefficient of oxidant with nitrogen oxide was 0.872, and that with nitrogen oxide and temperature simultaneously was 0.903. The multiple correlation equation used for this study may be expressed as follows:

• 실내환경 및 냄새 학회지
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• 제17권4호
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• pp.381-388
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• 2018

In this study, various conditions and phenomena that occur in the process of removing odorous VOCs by using electrolyzed oxidant were examined. The formation of hypochlorous acid, which is an oxidant produced by electrolysis, was investigated and the properties of the oxidizing agent used to decompose toluene, xylene, and cyclohexane were investigated. As a result, it was found that the production rate and the final concentration of the oxidizing agent increased with the current density. It was found that the degree of removal varies depending on the property of each pollutant. Interestingly, in the batch experiments in which the pH of the produced oxidant was controlled, it was found that the degree of elimination varied depending on the pH of the substance. These results suggest that the difference in the concentration and distribution of hypochlorous acid (HOCl) and hypochlorite ($OCl^-$) due to the pH change leads to the difference in oxidizing power on the oxidation characteristics of each substance. Styrene and terpineol showed better degradation characteristics than toluene and xylene in odorous VOC removal experiments by spraying electrolytic oxidant using a lab-scale continuous reactor. In conclusion, the removal of odorous VOCs by the electrolytic oxidant can have various applications in that it can oxidize pollutants of various spectra.

• 한국물환경학회지
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• 제20권5호
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• pp.409-414
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• 2004

Pilot-scale experiments were performed for the treatment of bank filtrate contammg high manganese concentration around 2mg/L using rapid manganese sand filtration to investigate effects of oxidant dose and pH control on the removal efficiency of manganese. For theoretical dose ranges of oxidant (sodium hypochlorite) between 3 and 4mg/L, the manganese concentration of effluent was 0.57 mg/L, which corresponded to 72.5% removal and was higher than drinking water quality standards of 0.3mg/L. For excess dose ranges of oxidant between 4 and 8mg/L, the manganese concentration of effluent was reduced to 0.14mg/L, which corresponded to 94.5% removal, but the residual chlorine concentration was over 1.0mg/L. On the other hand, manganese removal efficiency drastically increased up to the value of 98.0%, which is equivalent to the effluent concentration of 0.03mg/L by controling pH to the range between 7 and 8 for the theoretical dose of oxidant. Consequently, these results indicated that appropriate dose of chemicals, such as oxidant and alkali, and continuous monitoring of manganese should be necessary to obtain efficient removal of manganese and to optimize the maintenance of treatment facilities for the treatment of bank filtrate with high concentration of manganese.

• 생명과학회지
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• 제26권7호
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• pp.782-788
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• 2016

본 연구에서는 화장품의 천연소재로 사용 가능함을 알아보기 위해 추출부위가 각각 다른 총 11종의 자생식물의 항산화, 항주름에 관한 생리활성 효능을 스크리닝 하였다. DPPH scavenging assay 측정결과 100 μg/ml 농도에서 70% 넘는 활성을 나타낸 시료는 순비기나무, 송이고랭이, 방울고랭이, 큰고랭이, 자귀풀이었다. Hydrogen peroxide scavenging assay 측정결과 1,000 μg/ml 농도에서 물꼬챙이골을 제외한 10종이 90%넘는 활성을 나타내었다. Xanthine oxidase scavenging assay 측정결과 1,000 μg/ml 농도에서 순비기나무(Leaf; 86.3%)가 가장 높은 활성을 나타냈다. 4가지 항산화 실험에서 모두 효능이 우수하게 나온 시료는 순비기나무, 송이고랭이, 방울고랭이, 큰고랭이, 자귀풀이며 그중 collagenase 저해활성 측정결과 방울고랭이가 가장 높은 저해 활성을 나타내어 항산화 및 항주름에 효능이 있는 시료로 나타났다. 이러한 결과를 바탕으로 활성이 높은 자생식물은 화장품에 사용되는 천연소재로 이용이 가능한 좋은 수종으로 판단된다.

• 조명전기설비학회논문지
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• 제24권9호
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• pp.136-141
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• 2010

In this paper, after the third electrode type oxidant generator which could format non-uniform electric field in water had been manufactured and installed, by direct electrolysis, the effects of the hydrogen potential and oxidation reduction potential characteristics attendant upon electric field change on a higher concentration oxidant generation characteristics were investigated. Consequently, as the third electrode was installed in the middle of two slit electrodes and the polarity of applied power was changed, it was observed that the third electrode system with the positive electrode can generate a higher concentration oxidant, hydrogen potential and oxidation reduction potential as compared with that of the negative electrode. It is because the positive electrode was bombarded mostly energetic electrons and the negative electrode was bombarded mainly by less energetic positive ions.

• Environmental Analysis Health and Toxicology
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• 제30권
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• pp.6.1-6.7
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• 2015

Objectives This study aimed to estimate the effects of 4-nonylphenol (NP), a ubiquitously present surfactant in aquatic environments, on the anti-oxidant systems of the liver in the Far Eastern catfish Silurus asotus. Methods Changes in biochemical parameters involved in glutathione (GSH)-related and other anti-oxidant systems were analyzed following 4 weeks of 4-NP administration (0.1 and 1.0 mg/kg diet) via a formulated diet to catfish. Results 4-NP exposure induced an elevation in hepatic lipid peroxide levels and an accompanying decrease in reduced state GSH after 2 weeks, suggesting pro-oxidant effects of the chemical in catfish. This oxidative stress was associated with an inhibition of the GSH-utilizing enzyme glutathione peroxidase at the same time point. This inhibition was restored after 4 weeks. The activities of other anti-oxidant enzymes, i.e., glutathione reductase, superoxide dismutase and catalase were increased after 4 weeks. These enzyme increases occurred more strongly at the higher 4-NP concentration (1.0 mg/kg diet). Conclusions 4-NP given to catfish at 0.1 to 1.0 mg/kg diet, concentrations relevant to environmental levels, depletes the endogenous anti-oxidant molecule GSH and temporarily inhibits GSH-related anti-oxidant enzymes. Such declines in anti-oxidant capacity and elevated oxidative stress seem to be compensated eventually by subsequent activation of various anti-oxidant enzyme systems.

• 대한본초학회지
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• 제21권4호
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• pp.109-113
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• 2006

Objectives : In this study, anti-oxidant activity of Taraxacum platycarpum is confirmed to investigate cosmeceutical activity for utilization as a cosmetic ingredients. Methods : In the anti-oxidant and whitening effect experiment, the electron donating ability of Taraxacum platycarpum extracts, their SOD-like activity, and the inhibitory activity of xanthine oxidase, tyrosinase were examined. Results : Radical-scavenging activity of water and ethanol extract was examined using ${\alpha},{\alpha}-diphenyl-{\beta}-picrylhydrazyl$ (DPPH). Water and ethanol extract from Taraxacum platycarpum showed 62.9% and 54.7% at 500 ppm concentration in DPPH radical inhibition, respectively. In the test of superoxide dismutase (SOD)-like activity, water extract showed 63.4% at 1,000 ppm concentration, while ethanol extract showed 49% at 1,000 ppm concentration. In the test of xanthine oxidase inhibition, ethanol extract showed 66.8% at 1,000 ppm concentration. Tyrosinase inhibition effect related to whitening effect showed 36.3% and 54.2% in ethanol extract and water extract at 1,000 ppm concentration, respectively. Conclusion : According to these results, it is possible that the extract of Taraxacum platycarpum can be used as a new natural material of cosmetic industry.

• 대한한의학회지
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• 제23권3호
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• pp.174-187
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• 2002

Objectives : This study was carried out to determine whether Kamihaengche-tang plus Yulanijihwang-tang (KCYH) exerts a protective effect against oxidant-induced liver cell injury. Methods : Cell injury was estimated by measuring lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) release, and lipid peroxidation was estimated by measuring malondialdehyde, a product of lipid peroxidation in rabbit liver slices. Results : Oxidants (tBHP and $H_2O_2$) increased dose-dependently LDH release which was significantly prevented by 1% KCYH. The protective effect of KCYH against oxidant-induced cell injury was dose-dependent in the range of 0.05-1 % concentrations. Similarly, KCYH inhibited oxidant-induced lipid peroxidation in a dose-dependent manner. When liver tissues were exposed to Hg (0.5 mM), ALT activity in the medium and lipid peroxidation in tissues were markedly increased. These changes were prevented by 1% KCYH, KCYH restored toxicant-induced inhibition of cellular GSH content. KCYH increased the activities of catalase and glutathion peroxidase in oxidant-treated tissues. Conclusions : These results indicate that KCYH exerts a protective effect against oxidant-induced liver cell injury, and this effect is attributed to prevention of lipid peroxidation. These effects may be due to an increase in concentration of endogenous antioxidants.

• 한국연소학회지
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• 제3권1호
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• pp.11-19
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• 1998

The influence of oxidant addition on soot formation is investigated experimentally with ethylene, propane and mixture fuel co-flow diffusion flames. Oxidant addition into fuel shows the increase of integrated soot volume fractions for ethylene, ethylene/ethane and ethylene/methane mixture flames. However, the increase of integrated soot volume fraction with oxidant addition was not significant for propane and ethylene/propane mixture flames. This discrepancy is explained with $C_2\;and\;C_3$ chemistry at the early stage of soot formation process. The oxidant addition increases the concentration of $C_3H_3$ in the soot formation region, and therefore, enhances soot formation process. A new soot formation rate model that includes both dilution effect and chemical effect of oxygen is suggested to interpret the increase of integrated soot volume fractions with oxidant addition into ethylene. Also, the role of adiabatic flame temperature for the chemical effect of oxygen addition into fuel was reviewed. The influence of oxidant or diluent addition into fuel on soot formation process are the fuel dilution effect, the adiabatic flame temperature altering effect and/or the chemical effect of oxygen. Their relative importance could change with fuel structure and adiabatic flame temperature.

• 대한본초학회지
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• 제26권4호
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• pp.181-185
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• 2011

Objectives : The Zanthoxylum pericarpium has been used as oriental spicy seasoning and a medicinal plant from old times. This study was performed to determine the anti-oxidant efficacy of Zanthoxylum pericarpium extract and the anti-microbial effects. Methods : We got Zanthoxylum pericarpium extract using PSE (pressurized solvent extraction) method. The anti-microbial effect of Zanthoxylum pericarpium extract was assessed on Streptococcus mutans(S. mutans) and anti-oxidant effect of the extract was assessed by measuring DPPH radical scavenging activity and SOD like activity. Results : 1. Zanthoxylum pericarpium extract had high anti-microbial activity on S. mutans. 2. DPPH radical scavenging activity significantly increased in the Zanthoxylum pericarpium extract. 3. SOD like activity also significantly increased in the Zanthoxylum pericarpium extract. Conclusions : The PSE extract from Zanthoxylum pericarpium has good anti-microbial and anti-oxidant effects in a concentration-dependent manner.