• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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• pp.196-196
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• 2014

플라즈마 건식 식각 기술은 반도체 식각공정에서 효과적으로 이용되고 있으며, 반도체 소자의 크기가 줄어듬에 따라 미세하고 정확하게 식각 깊이를 제어할 수 있는 원자층 식각 기술이 개발되었다. 3-5족 반도체 소자의 Interface Passivation Layer 로 이용되는 $Al_2O_3$ 와 BeO 의 원자층 식각을 하였으며, 각각의 원자층 식각 조건과 식각 후의 표면 거칠기 변화에 대한 영향을 확인 할 수 있었다.

• Advances in Traditional Medicine
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• 제10권1호
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• pp.21-28
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• 2010

The objective of the present investigation is to evaluate the antimicrobial potency of the terpenoid fractions isolated from Luffa cylindrica seeds against various pathogenic microbes. The seeds were powdered and extracted with methanol in soxhlet appratus based on phytochemical screening. Three terpenoid components were isolated by column chromatography and identified by thin layer chromatography and chemical analysis which were designated as ${LCSF_4}^*$, ${LCSF_6}^*$ & ${LCSF_8}^*$ respectively. Disc diffusion method was employed to determine the antimicrobial effectiveness of test compounds I, II and III $({LCSF_4}^*,\;{LCSF_6}^*\;&\;{LCSF_8}^*)$ against 6 microbial species viz., Staphylococcus (S.) aureus, Bacillus (B.) subtilis, Escherichia (E.) coli, Pseudomonas (P.) aeruginosa, Candida (C.) albicans and Aspergillus niger. The disc was saturated with $100{\mu}l$ of each compound, allowed to dry and introduced on the upper layer of seeded agar plate. The plates were incubated overnight at $37^{\circ}C$. Microbial growth was determined by measuring the zonal inhibition diameters. Compound I showed maximum potency against gram positive S. aureus (21 mm) in comparison with standard ciprofloxacin (38 mm), whereas the same compound was completely devoid of activity against both the fungi tested. Compound II was found to be highly sensitive against both the gram negative E. coli (20 mm) and P. aeruginosa (22 mm). Compound II was found to exhibit maximum potency against the fungi C. albicans (15 mm) and A. niger (20 mm). Compound III was found to be very effective against both the gram positive S. aureus (20 mm) and B. subtilis (15 mm) respectively.

• 한국연초학회지
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• 제17권2호
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• pp.103-108
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• 1995

Antibiotic and physico-chemical properties of an active compound from actinomycetes isolate G-37, of which the culture filtrate had an inhibitory effect against tobacco mosaic virus(W) infection, were examined. The active compound, which was purified by ethylacetate extraction, silica gel column chromatography, preparative thin layer chromatography, and high performance liquid chromatography, showed strong antibacterial activities especially against Gram-positive bacteria including Bacillus subtillis, Sarcina lutea and Staphylococcus aureus. From the IH-NMR, FAB/RfS, UV spectral data, and physicochemical properties, the active compound of G-37 appears to belong to a peptide antibiotic group. Among the known peptide antibiotics in the antibiotic group, No. 280, A-30912, and Taitomycin showed molecular weights and ultra violet spectrum similar to those of the active compound from G-37, but was not identical to the compound, which suggests that it may be a new peptide antibiotics.

• Journal of Welding and Joining
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• 제20권3호
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• pp.16-23
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• 2002

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2001년도 추계학술발표대회 개요집
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• pp.99-102
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• 2001

• 대한화학회지
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• 제11권2호
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• pp.45-50
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• 1967

有機할로겐化合物의 分離方法으로써 試料의 中性子照射에 依한 放射化 Thin Layer Chromatography를 Methanol을 展開溶媒로 하여 硏究한 結果 各種 할라이드, 할로겐酸, 할로겐알데하이드 等에서 銳敏한 展開 peak를 얻었으며 混合物의 展開에서도 定性確認에 充分한 分離 peak를 얻었다. 多 할로겐化合物, 芳香核鹽化物에 있어서는 試料의 中性子線 照射에 依하여 한 個 以上의 放射化할로겐化合物이 生成되어 確認이 困難하였으며 其他 할로겐 化合物에서는 再現性있는 Rf値를 얻을 수 있었다. 그리고 實驗方法을 記述하고 本 方法의 有用性에 關하여 論議하였다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.125-127
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• 2000

We report high pressure synthesis of Sr$_{0.9}$Sm$_{0.1}$CuO$_2$. Powder x-ray diffraction showed that the synthesized compounds have infinite layer structure as a major component. Slow heating at the first stage of heating processes after pressurization resulted in several larger grains. The largest grain was found to have the longest edge length of about 100 micrometer. Through magnetic property measurement in superconducting state, we found that pinning in this compound has substantial difference from that of La doped infinite layer, which has no unpaired spin at Sr site.

• 한국표면공학회지
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• 제41권2호
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• pp.57-62
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• 2008

Electrochemical properties of Ti-30Ta-$(3{\sim}15)$Nb alloys coated by HA/Ti compound layer have been studied by various electrochemical method. Ti-30Ta binary alloys contained 3, 7, 10, and 15 wt% Nb contents were manufactured by the vacuum furnace system. The specimens were homogenized for 24 hrs at $1000^{\circ}C$. The samples were cut and polished for corrosion test and coating. It was coated with HA/Ti compound layer by magnetron sputter. The HA/Ti non-coated and coated morphology of Ti alloy were analyzed by x-ray diffractometer(XRD) and filed emission scanning electron microscope(FE-SEM). The corrosion behaviors were investigated using potentiodynamic method in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. The homoginazed Ti-30Ta-$(3{\sim}15wt%$)Nb alloys showed the ${\alpha}+{\beta}$ phase, and ${\beta}$ phase peak was predominantly appeared with increasing Nb content. The microstructure of Ti alloy was transformed from needle-like structure to equiaxed structure as Nb content increased. HA/Ti composite surface showed uniform coating layer with 750 nm thickness. The corrosion resistance of HA/Ti composite coated Ti-alloys were higher than those of the non-coated samples in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. Especially, corrosion resistance of Ti-Ta-Nb system increased as Nb content increased.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.101-105
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• 2001

고압용 가교 Polyethylene 절연 케이블의 도체와 절연체 사이, 절연체와 외부 차폐층 사이에는 계면에서의 부분방전을 방지하고 전기적 스트레스를 완화할 목적으로 반도전층이 설계되어 있다. 이 반도전층의 성질은 케이블의 품질과 신뢰성에 매우 중요한 관련이 있다. 일반적으로 반도전층은 압출 성형하는데 Base Polymer에 다량의 카본블랙을 혼합하여 도전화 한다. 절연층과 반도전층간 계면의 평활도는 전력 케이블의 수명과 깊은 관계가 있는데 만약 평활도가 좋지 않으면 전기적 Stress 가 증가하여 전선 수명이 짧아진다. 계면 평활도를 나쁘게 하는 주 요인은 계면의 Void, 반도전층의 돌기와 이물, 탄화물 등이다. 반도전 Compound 제조에 있어서 Carbon Black의 선택과 분산성은 전선수명을 결정하는 중요한 요소이다.

• 한국초전도ㆍ저온공학회논문지
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• 제4권1호
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• pp.30-34
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• 2002

In this Paper, Insulation of current lead in the conduction-cooled DC reactor for the 1.2kV class 3 high-Tc superconducting fault current limiter(SFCL) is studied. Thermal link which conducts heat energy but insulates electrical energy is selected as a insulating device for the current lead in the conduction-cooled Superconducting DC reactor. It consists of oxide free copper(OFC) sheets, Polyimide films, glass fiberglass reinforced Plastics (GFRP) plates and interfacing material such an indium or thermal compound. Through the test of dielectric strength in L$N_2$, polyimide film thickness of 125 ${\mu}{\textrm}{m}$ is selected as a insulating material. Electrical insulation and heat conduction are contrary to each other. Because of low heat conductivity of insulator and contact area between electrical insulator and heat conductor, thermal resistance of conduction-cooled system is increased. For the reducing of thermal resistance and the reliable contact between Polyimide and OFC, thermal compound or indium can be used As thermal compound layer is weak layer in electrical field, indium is finally selected for the reducing of thermal resistance. Thermal link is successfully passed the test. The testing voltage was AC 2.5kVrms and the testing time was 1 hour.