• Journal of the Korean Chemical Society
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• v.15 no.1
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• pp.23-35
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• 1971

Bislang konnte der Hochregenerativpyrokohlenstoff nur bei hohen Abscheidungstemperaturenvon $2100^{\circ}C-2200^{\circ}C$ hergestellt werden. Daher versuchte es in der vorliegenden Arbeit, ihn bei niedrigeren Abscheidungsternperaturen herzustellen und wurde gefunden, da$\ss$ der Hochregenerativpyrokohlenstoff auch bei der Abscheidungsternperaturen von $1700^{\circ}C$ hergestellt werden kann. Methan wurde in einem nach der Hei$\ss$wandmethode erhitzte Str$\"{o}$mungsrohrreaktor zersetzt und als Substratmaterial wurden gesintertes Aluminiumoxidrohr und impr$\"{a}$gniertes Graphitrohr verwendet. Die senkrechte Stellung der Versuchsanlage erwies sich als g$\"{\u}$nstiger als die waagrechte Stellung derVersuchsanlage. Eigenschaften wie Dichte, R$\"{o}$ntgen feinstrukturparameter und Zugfestigkeit des in der vorliegenden Arbeit hergestellten Hochregenerativpyrokohlenstoffes wurden mit den anderen Pyrokohlenstoffsorten sowie mit den Literaturwerten f$\"{u}$r den Hochregenerativpyrokohlenstoff vergleichend untersucht.

• KSBB Journal
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• v.11 no.1
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• pp.71-76
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• 1996

Studies were carried out to examine some factors affecting the supercritical carbon dioxide extraction of taxol from the bark of Taxus cuspidata using a continuous packed bed extractor. The factors investigated in this study were pressure, temperature, volume of carbon dioxide, and co-solvent. It was found out that the amount of taxol extracted was not significantly affected by the operating pressure in the absence of a co-solvent although it increased by about 20% at 5500 psig. With $24\ell$ of carbon dioxide the saturated amount of taxol was extracted at 318K and 5500psig. Methanol was found to be the most effective co-solvent in terms of amount of taxol extracted among six different co-solvents used. When methanol was used as a co-solvent the effect of operating pressure became significant; approximately 50% increase in the amount of taxol extracted was observed at 3000 psig as compared to at 2500 or 3500psig. The optimum methanol concentration in supercritical fluid was 13% (w/w)at 308K, 3000psig.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.77-83
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• 2010

The fructus of Crataegus pinnatifida Bunge (CBF) has been used as medicinal and food source in worldwide. In this study, antimicrobial activity of the methanol extract and its sequential organic solvent fractions of CBF against different pathogenic bacteria and fungi, including multidrug resistant Pseudomonas aeruginosa and Candida sp., were investigated. The methanol extract of CBF was active against various gram-positive and gram-negative bacteria, and the ethylacetate and butanol fractions of CBF showed strong antibacterial activity against Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Salmonella typhimurium, Proteus vulgaris, Escherichia coli and various multidrug resistant Pseudomonas aeruginosa with minimal inhibitory concentration of 1.0~7.5 mg/mL. Also the fractions showed anti-Candida activity against C. albicans, C. kruseis and C. geochares. The methanol extract of CBF and its solvent fractions, except n-hexane fraction, did not show any hemolytic activity against human red blood cell up to $500\;{\mu}g/mL$, respectively. The hemolysis in n-hexane fraction at $500\;{\mu}g/mL$ was less than 9.9%. Our results suggest that the CBF could be developed as a potent antibacterial agent, especially for multidrug resistant Pseudomonas aeruginosa.

• Journal of Environmental Science International
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• v.13 no.7
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• pp.697-701
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• 2004

Most of methane gas result from waste matter in landfill, therefore the persons concerned take an increasing interest in management of gases in landfill. Infrared Gas Analyzer was used to measure components of gases, $CH_4,$ $CO_2,$ $O_2,$ through gas exhausted pipe. To measure amount of the gas flow meter(Portable Hot-Line Current Meter) was used and it was set at right angles with direction of the flow. In this research the total amount of methane gas produced in Beck-Suk Landfill was calculated through FOD method suggested by IPCC. This research found that in Chon-An Beck-Suk Landfill anaerobic resolution was made actively and the amount of methane gas produced there was 54.14%, which is higher than common figure, 50%, in other researches. The components of reclaimed waste matter, especially, organic waste matter can have a great effect of the amount of the greenhouse gases produced in landfill. We can expect that the amount of greenhouse gas will decrease from 2005, when it will be prohibited from carrying kitchen refuse and sludge into landfill.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.1
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• pp.1-8
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• 2004

An study has been performed with axisymmetric coflow diffusion flames to investigate the influence of air-side fuel side dilution and initial preheated temperature on the soot formation in methan/air flames. Soot quantities are determined by using PLII(Planar Laser Induced Incandescence), such a $C_2$H$_2$ major species(CH$_4$, $O_2$, $N_2$) and temperature are simulated by chemkin code. The numerical analysis was performed with transport properties and detailed reaction mechanisms m axisymmetric coflow diffusion flames. The study of how flame temperature and $N_2$ dilution of air and fuel side influence the soot concentrations is focused. Soot concentrations results on PLII show that preheated temperature contributes to an increase in the soot volume fraction, and soot formation Is more productive to air side dilution than to fuel side dilution. $C_2$H$_2$ concentrations have a similar tendency to soot concentrations.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 1999.11a
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• pp.5-24
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• 1999

There are severl types of Eco-village developed in abvanced countries including urban, suburban and rural style. For the establishment of Eco-village in Korea, it was focussed to introduce the rural style which has been developed inyersively in European countries such as Denmark, England and Germany. As a key cencept for Eco-villge it was explained briefly and discussed on the renewable energy(wind power park, bio-mass and solar energy collector and heating system), eco-architure, methane gas device, living machine (wastewater treatment facility) and organic farming. It was also discussed how important the basic standard and guidelines for organic agriculture to run essential for the system. For this reason major principles of international applicable standard(draft) for organically grown foods by FAO/WHO Codex alimentarius was shortly desidered. as one of very suitable type for Environmental Agriculture Districts Program which Korean govenment is going to establish in the near future. In conculusion it was also suggested that positive participation of organic famers, enthusiastic eneagement of inhabitans and support strategy of govemment /NGO groups might play very important role for successful managment of Eco-village ecologically sustainable after establishment.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.553-553
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• 2009

LFG는 약 4,500kcal/$m^3$의 높은 발열량을 가지는 에너지원으로 활용이 가능한 동시에 GWP가 21인 $CH_4$를 제거함으로써 탄소배출권(CERs) 확보를 통해 CDM 또는 ET 시장에서 유리한 위치를 선점할 수 있다. LFG의 활용기술에는 발전과 중질가스 및 고질가스 형태의 연료로 생산하는 방식이 있다. 하지만 기존의 기술은 LFG의 발생량이 일정규모 이상인 매립지에서 경제성을 가지기 때문에 국내에서는 14곳의 대형 매립지에서만 에너지원으로 활용하고 있다. 그 외 중소규모 매립지에서는 대기중으로 방출하거나 소각하여 처리하므로 가용한 에너지원이 버려지고 있을 뿐만 아니라 지구온난화에 영향을 미친다. 본 연구에서는 중소규모 매립지에서 발생하는 LFG를 경제성을 가지는 에너지원으로 활용하기 위하여 하이드레이트화를 이용한 $CH_4$ 분리, 정제, 수송 연구를 진행하였으며, 이러한 연구의 일환으로 pure $CH_4$를 대상으로 하이드레이트 형성 시 구동력(driving force)에 따른 induction time, growth rate, gas consumption 측정을 통하여 LFG를 이용한 가스 하이드레이트 생산을 위한 운전조건 선정을 위한 기본 자료로 사용하고자 한다.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.549-555
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• 1996

Diamond Like Carbon film is amorphous film which is considered to consist of three coordinate graphite structure and tetrahedron coordinate diamond structure. Its hardness, thermal conductivity and chemical stability are nearly to one of diamond. It is well known to become semi-conductor by doping of inpurity. In this study Diamond Like Carbon film was synthesized by Microwave Plasma CVD in the gas mixture of hydrogen-methan-nitrogen and doped of nitrogen on the single-crystal silicon or silica glass. The temperature of substrate and nitrogen concentration in the gas mixture had an effect on the bonding state, structural properties and conduction mechanism. The surface morphology was observed by Scanning Electron Microscope. The strucure was analyzed by laser Raman spectrometry. The bonding state was evaluated by electron spectroscopy. Diamond Like Carbon film synthesized was amorphous carbon containing the $sp^2$ and $sp^3$ carbon cluster. The number of $sp^2$ bonding increased as nitrogen concentration increased from 0 to 40 vol% in the feed gas at 1233K substrate temperature and at $7.4\times10^3$ Pa. Increase of nitrogen concentration made Diamond Like Carbon to be amorphous and the doze of nitragen could be controlled by nitrogen concentration of feed gas.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.39-44
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• 2007

The Rqh1 gene is essential for vegetative growth in fission Yeast. The rqh1 mutant showed that sensitivity of DNA damaging agent, a wild range of phenotype including abnormal gene expression and cell elongation. This result showed that the rqhl-overexpression cell was sensitivity to DNA damaging agent like rqhl mutant. When Rqh1 have an over-expression by $nmt1^+$ promoter of pREP vector, rqh1 mutant DNA damaging agent sensitivity could be compensated. We isolated two strong mutant containing complementation gene, rqh156 and rqh172, respectively. This result observed that the DNA damaging agent sensitivity of rqhl mutant was complemented by the expression of rqh156 and rqh172. They induced mRNA expression in a dose-dependent manner HU, MMS and UV. The HU sensitivity of the rqhl was complemented by the expression of rqh156 and rqh172. The mRNA expression of rqh156 decreased on HU dose dependent but the mRNA expression of rqh172 did not decrease on HU dose dependent. The MMS and W sensitivity of the rqhl was complemented by the expression of rqh156 and rqh172. These results indicate that the isolated rqhl gene may play an important role in DNA metabolism.

• Korean Journal of Agricultural Science
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• v.19 no.1
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• pp.103-114
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• 1992

Screening for antioxidative activities of 180 species of crude drugs were performed on their methanol extracts. More than 45% of those showed some effect on oxidative stability of linoleic acid, and 44 species seemed to have rather strong antioxidative activity. Selected these samples of the active crude drugs were further examined in their methanol extracts with methyl linoleate emulsion system. especially 11 species revealed strong antioxidative activity. These 11 species were then successively extracted with ethyl acetate and petroleum ether, and their antioxidative activity was determined. The ethyl acetate and petroleum ether extracts of Epimedium Koreanum NAKAI, Psoralea Corylifolia L., Syringa Dilata NAKAI and Prunus mume Sieb, et Zucc. showed much more effective than the others in stabilizing methyl linoleate. Scutellaria baicalensis George. Glycyrrhiza glabra L. were only effective in the methanol extract.