• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.127-131
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• 1998

Ethane was measured to know whether active oxyzens may induce phytoxicity in stressedcucumber plant.The time course of the increase in ethane evolution was the same as that of the increase of visible injury in all treatments except $SO_2$ treatment.This result showed that air pollutants-induced plant damages were closely related to ethane evolution.And evolution of ethane was more increased in combined stress than singly one,suggesting that phytotoxicity was more severe in complex sterss.Also, evolution of ethane was enhanced in the light condition and scavengers of active oxygen were inhibited,showing that plant damage that plant damage were cause by active oxygens.

• Journal of the Korean Chemical Society
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• v.25 no.5
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• pp.311-317
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• 1981

A new nickel(II) compound, $Ni(CH_2SiMe_3)_2((C_6H_5)_2PCH_2CH_2P(C_6H_5)_2)$, 1, has been prepared by the reaction of $NiCl_2((C_6H_5)_2PCH_2CH_2P(C_6H_5)_2)$ with $Me_3SiCH_2Li$. The compound, 1, is stable under nitrogen at room temperature both in solution and in the solid state. Thermal decomposition of 1 in solution or in the solid produces the reductive coupling product, $Me_3SiCH_2CH_2SiMe_3$ which is also afforded by the reactions of 1 with CO and $O_2$ at room temperature, and with $(C_6H_5)_2PCH_2CH_2P(C_6H_5)_2$ at 80${\circ}$C.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.182-185
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• 2008

최근 새로운 천연가스 수송/저장법으로 가스 하이드레이트 형성법이 주목받고 있다.본 연구에서는 천연가스의 저장 매체로 다공성 매질인 실리카 젤을 사용하였다. 다공성 실리카 젤을 사용할 경우 물과 기체의 접촉면적을 극대화 시킬 수 있어 가스하이드레이로의 전환율을 높일 수 있다. 본 연구에서는 천연가스 주성분인 에탄과 프로판 기체를 사용하였으며, 기공의 직경이 각각 6.0 nm, 15.0 nm, 30.0 nm, 100.0 nm의 다공성 실리카 젤을 사용하였다. 에탄은 270 $\sim$ 285 K의 온도범위와 9 $\sim$ 25 bar의 압력범위, 프로판은 260 $\sim$ 280 K의 온도범위와 1.8 $\sim$ 2.8 bar의 압력범위에서 기공 크기의 분포를 고려하여 하이드레이트(H)-물($L_W$)-기상(V)의 3상 평형점을 측정하였다. 측정 결과 기공의 크기가 작아질수록 각각의 벌크 상태의 에탄 및 프로판 하이드레이트에 비해 하이드레이트의 평형조건이 온도는 낮아지고 압력이 높아지는 저해효과가 커짐을 알 수 있었다. 천연가스 수송/저장으로서 응용을 고려할 경우 저해효과가 적은 100.0 nm이상의 다공성 실리카 젤을 사용하는 것이 적절할 것으로 사료된다. 본 연구에서 얻어진 결과는 천연가스 수송/저장뿐만 아니라 심해저 천연가스 개발, 이산화탄소 심해저장 등의 가스 하이드레이트 용용 연구에도 유용한 기초 자료가 될 것이다.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.584-587
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• 2008

최근 새로운 천연가스 수송/저장 방법으로 가스 하이드레이트 형성법이 주목받고 있다. 본 연구에서는 천연가스의 저장 매체로 다공성 실리카 젤을 사용하였다. 다공성 매질을 사용할 경우 물이 기체와 접촉하는 면적이 극대화되어 하이드레이트로의 전환율이 높아진다. 기공의 직경이 각각 6.0, 15.0, 30.0 nm의 실리카 젤을 사용하여 270 - 285 K의 온도 범위와 0.5 - 3.0 MPa의 압력 범위에서 기공 크기의 분포를 고려하여 에탄 하이드레이트의 3상 평형점 (하이드레이트 (H) - 물 (LW) - 기상 (V))을 측정하였다. 기공의 크기가 작아질수록 벌크 상태의 에탄 하이드레이트에 비해 하이드레이트 평형 조건이 온도는 낮아지고 압력이 높아지는 저해효과가 커짐을 알 수 있었다. 천연가스 수송/저장으로의 응용을 고려할 경우 저해효과가 적은 30.0 nm 이상의 실리카 젤을 사용하는 것이 유용할 것으로 사료된다. 본 연구의 결과는 심해저 천연가스 개발, 이산화탄소 심해저장 등의 가스 하이드레이트 응용 연구에도 유용한 기초자료가 될 것이다.

• Journal of Power System Engineering
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• v.10 no.2
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• pp.75-82
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• 2006

세계적인 환경 보호 정책에 따라 할로겐화탄소 냉매를 대체할 환경 친화적인 초저온 냉매의 개발과 연구가 활발히 진행되고 있다. 일반적으로 캐스캐이드 2원 냉동 시스템에서 아직까지 할로겐화탄소 냉매가 널리 사용되고 있다. 탄화수소 화합물의 한 종류인 에탄은 낮은 지구 온난화 지수와 낮은 오존층 파괴지수를 가진 친 환경적인 자연 냉매이다. 본 연구는 지구 온난화 지수가 높은 R-23 냉매와 비교하여 캐스캐이드 2원 냉동 시스템에서 에탄의 성능 시험을 목적으로 수행 하였다. 1원측에는 R-22를 사용하였으며, 증발 온도에 따른 성능은 R-23 보다 에탄(R-170)이 더 높게 나타났다.

• KSBB Journal
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• v.11 no.6
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• pp.642-648
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• 1996

The effects of EDTA(Ethylene diamine tetraacetic acid), Cu, temperature, and gas(methane and oxygen) composition on methanol production from methane with Methylosinus trichosporium were investigated. In this experiment EDTA was found to be a potential methanol dehydrogenase inhibitor since it causes methanol accumulation and 6mM was found to be optimum concentration of EDTA for methanol production. When Cu was added in culture media, the produced methanol concentration level was increased. Hence it is believed that Cu enhanced the particulate methane monooxygenase formation and consequently the addition of Cu could increase the methanol production from methane. In this experiment the optimum concentration of Cu was found to be 1mM for methanol production. When temperature was shifted down from $30^{\circ}C to 25^{\circ}C$, the methanol production level was enhanced by 50%. When the ratio of methane to oxygen in gas phase was increased to 2.3 from 1, produced methanol concentration was also enhanced by 100%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.910-914
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• 2005

This study was to determine the inhibitory effect of ethanol extract of leaf, bark and xylem of Quercus aliena Blume and, consecutively, of organic solvent subfractions against food borne pathogens. The ethanol extracts of leaf, bark and xylem of Quercus aliena Blume were shown to have antimicrobial effect against Gram-positive and Gram-negative bacteria. Listeria monocytogenes and Salmonella Typhimurium were more resistant to ethanol extracts of the Quercus aliena Blume tissues compared with Bacillus cereus and Escherichia coli O157:H7. The ethanol extract of Quercus aliena Blume leaf showed the strongest antimicrobial activity against food borne pathogens, followed by those of xylem and bark. The ethanol extract treatment $(500\~1,000\mu g/mL)$ of Quercus aliena Blume leaf completely reduced the growth of B. cereus and L. monocytogenes within 24 hour whereas $2,000\mu g/mL$ of ethanol extract was needed for complete growth inhibition of E. coli O157:H7 and S. Typhimurium. Among organic solvent subfractions obtained from the ethanol extract of leaf, bark and xylem of Quercus aliena Blume, the ethyl acetate fraction showed the strongest antimicrobial activity, but no antimicrobial activity was observed in chloroform, hexane and water fractions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.109-115
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• 1997

This study was designed to investigate the effects of methionine(Met) on the activities of brain lipid peroxidation related enzymes in ethanol administrated rats of selenium(Se) deficiency. Male Sprague-Dawley rats were fed Se deficiency diets containing one of the three levels of Met (0, 3, 9g/kg diet) and ethanol(2.5g/kg of body weight) was administrated as 25v/v% ethanol treated groups orally. The rats sacrificed after 5 and 10 weeks of feeding periods. Alcohol dehydrogenase activity was increased in ethanol treated groups and was higher Met normal group than Met deficiency and excessive groups at 5 and 10 weeks dieting. Aldehyde dehydrogenase activity was decreased in ethanol treated groups and significantly decreased in Met deficiency group. Monoamine oxidase activity in brain was increased in ethanol treated groups and was predominently increased in Met deficiency groups. Superoxide dismutase and glutathione peroxidase activities were decreased in ethanol treated groups and tended to increase in proportion to level of dietary methionine. Glutathione S-transferase and catalase activities and lipid peroxide content were increased by ethanol administration and were higher Met deficiency group than normal and excessive groups.

• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.171-179
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• 2005

This study was investigated on antioxidative and antimicrobial activities of PSW(pomegranate seed water extract), PSE(pomegranate seed ethanol extract) and PSO(pomegranate seed oil). The extraction yields of PSW, PSE and PSO were 28.9, 13.0 and $4.9\%$, respectively. Total phenol contents of PSW, PSE and PSO were 47, 78 mg/g(dry basis) and 40 mg/g, respectively. Electron donating abilities of PSW, PSE and PSO at 1,000 ppm were 18.8, 28.5 and $9.7\%$, respectively. Antioxidative activities in Iinoleic acid substrates at 500 ppm were in order of PSE > $\alpha-tocopherol$ > PSW > PSO. Antioxidative activities in Iinoleic acid emulsion substrates at 200 ppm were in order of $\alpha-tocopherol$l > PSE > PSW > PSO. In antimicrobial activity, PSO showed growth inhibition effect against Micrococcus luteus, Salmonella enteritidis and PSW showed growth inhibition effect against Bacillus cereus, Escherichia coli. Whereas antimicrobial activity of PSE was not observed. The nitrite-scavenging abilities of PSW, PSE and PSO at 2,000 ppm were 27.5, 23.7 and $39.6\%$, respectively. And the SOD-like activities of PSW, PSE and PSO at 1,000 ppm were 15.9, 34.9 and $0.10\%$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.675-681
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• 1997

This study was conducted to investigate the effect of dietary protein and fiber levels on the activities of ethanol metabolizing enzymes of liver in ethanol-treated rats. Sprague-Dawley male rats were fed on diets containing two levels of protein(7, 20%/kg diet) and pectin(5, 10%/kg diet). In ethanol experiments, ethanol(25% v/v) was administered by oral intubation(5g/kg body weight) at the same time once a day Control animals received an isocaloric dose of sucrose. The rats were sacrificed after 5 weeks of feeding periods. Alcohol dehydrogenase and microsomal ethanol oxidizing system activities of hepatic tissue were increased more in ethanol-treated groups than in control groups. Increment of activities predominated in normal protein normal fiber group. Aldehyde dehydrogenase activity was decreased in ethanol-treated groups and significantly decreased in normal Protein normal fiber group. Cytochrome P-450 content was significantly increased in ethanol-treated groups and Predominated in normal protein groups. Xanthine oxidase activity was increased in ethanol-treated groups, but not significantly except normal protein normal fiber group. Glutathione content tended to increase in proportion to level of dietary protein and was higher in normal fiber groups than in high fiber groups, whereas it was decreased by ethanol treatment. Lipid Peroxide content was significantly increased in low Protein normal fiber groups.