PH_(3)를 흡착한 Si(100) 표면의 수소탈리 : TPD를 통한 연구 A TPD study

유동선 國立 昌原大學校 基礎科學硏究所 1994 基礎科學硏究所論文集 Vol.6 No.-

H_(2) desorption from PH_(3) adsorbed Si(100) surface was examined by TPD(temperature programmed desorption) experiment. When PH_(3) partial pressure was 1×10^(-8)Torr and PH_(3) exposure was 30L, it was found that for adsorption temperature higer than 350℃, the TPD area decreased with increasing adsorption temperature. It was also observed that the peak temperature of TPD signals was shifted toward higher temperature with increasing adsorption temperature. The reason for this peak shift was thought to be surface P concentration and this P concentration was calculated through readsorption experiment. As a result of this readsorption experiment at 450℃, It is proposed that a relationship between surface P concentration and the temperature of the TPD peaks. For example, when the P concentration is 0.38ML the temperature of TPD peak is 562℃.

가상가공기법을 이용한 볼엔드밀과 플랫엔드밀의 절삭력 해석 시스템 개발

유동일,김석일,윤태선 한국 항공대학교 항공산업기술연구소 1998 航空宇宙産業技術硏究所 硏究誌 Vol.8 No.-

본 연구에서는 볼엔드밀과 플랫앤드밀에 의해서 야기되는 절삭력을 가상적으로 평가할 수 있는 기반을 구축하기 위한 노력으로써 가상가공기법을 이용한 절삭력 해석 시스템을 구현하였다. 공구의 기하학적 제원과 공작기계(밀링머신, 머시닝센터)의 운전 조건에 의해서 변화되는 절삭력은 공작물과 공구의 접촉영역 내에 위치한 미소 절삭날에 적용하는 미소 절삭력들을 중첩시키는 방법을 통해서 해석하였다. 특히 구조변형을 고려한 절삭력은 절삭력과 구조변형의 평형조건을 이용해서 결정하였다. 아울러서 볼엔드밀과 플랫엔드밀의 절삭력에 대한 실험결과와 해석결과의 비교를 통해서 본 연구에서 개발한 절삭력 해석 시스템의 유용성을 입증하였다. In this study, a cutting force analysis system for ball and flat end-mills is realized based on the virtual manufacturing technologies. Cutting force which depends on the specification of cutting tool and operating conditions of machine tool(milling machine, machining center), is predicted by superposing the infinitesimal cutting forces on infinitesimal cutting edges existing in the contact area between cutting tool and workpiece. Especially, the equilibrium condition between cutting force and structural deformation of cutting mechanism is introduced to determine the cutting force considering the influence of structural deformation. And comparison between the predicted and measured cutting forces for ball and flat end-mills shows the effectiveness of the cutting force analysis system developed in this study.

LCVD 법에 의한 Silicon의 박막 생장과 시료의 광학적 성질에 관한 연구

劉東宣 國立 昌原大學校 産業技術硏究所 1988 産技硏論文集 Vol.2 No.-

CO₂laser CVD (laser induced chemical vapor deposition) system was constructed and silicon thin films were deposited by using SiH₄. The silicon films were deposited at a deposition rate of 1600Å/min at room temperature, at CO₂laser 14w/㎠ under SiH₄pressure 0.01 torr on quartz plate when irradiation time was 11 minutes, and the deposition rate depends on the irradiation time. The absorption coefficients and optical gaps were very small at visible region and the conductivities were very large at room temperature and this show that the deposited films has polycrystalline structure.

Glow放電法에 의한 α-Si蒸着裝置의 製作과 그 試料의 特性

유동선,현옥배,고년규,황정남,정원모,이철주 연세대학교 자연과학연구소 1981 學術論文集 Vol.7 No.-

Glow방전법에 의해서 SiH_4를 분해하여 α-Si 박막을 얻을수 있는 장치를 제작하였다. 이 SiH_4기체는 수소기체속에서 10%로 희석되였으며, 진공방전함속에서 rf 전압에 의하여 분해된 Si는 유리기판위에 증착된다. α-Si박막은 1~1.6 A˚/sec의 증착율로 약 7000 A˚의 두께까지 증착되였다. α-Si 박막의 흡수계수는, 2.3 eV의 photon energy 영역에서 약 10^4 cm^-1이고, 그 optical gap은 약 2.1 eV였다. 이 박막의 증착율은 전극간격에 따라 변하고 있으나, 최적전극간격과 기체유입량은 각각 2.6cm와 1~2cc/min였다. Apparatus capable of producing α-Si film by the glow discharge method was designed and constructed in this study. The monosilane gas which is diluted in H_2 gas to 10% is decomposed in the reaction chamber by rf oscillation. The apparatus is composed of a reaction chamber, a rf generator, a cooling system, etc. The α-Si thin film is produced at a deposition rate of 1~1.6 A˚/sec to a thickness of about 7000 A˚. Its absorption coefficient is about 10^4 cm^-1 in the photon energy region of ~2.3 eV, and its optical gap is about 2.1 eV. The deposition rate for the film is controlled by varying the distance between electrode and substrate. The optimum distance and gas flow is about 2.6 cm and 1~2 cc/min, respectively.

PH₃를 흡착한 Si(100) 표면의 수소탈리:TPD를 통한 연구

유동선 國立昌原大學校 基礎科學硏究所 1994 基礎科學硏究所論文集 Vol.6 No.-

H₂desorption from PH₃adsorbed Si(100) surface was examined by TPD(temperature programmed desorption) experiment. When PH₃partial pressure was 1×10?Torr and PH₃exposure was 30L, it was found that for adsorption temperature higher than 350℃, the TPD area decreased with increasing adsorption temperature. It was also observed that the peak temperature of TPD signals was shifted toward higher temperature with increasing adsorption temperature. The reason for this peak shift was thought to be surface P concentration and this P concentration was calculated through readsorption experiment. As a result of this readsorption experiment at 450℃, It is proposed that a relationship between surface P concentration and the temperature of the TPD peaks. For example, when the P concentration is 0.38ML the temperature of TPD peak is 562℃.

SPTE 및 GC-MS를 이용한 한국산 및 중국산 생강의 향미 특성 분석

유주원,김남선,김건,이동선 서울여자대학교 자연과학연구소 2005 자연과학연구논문집 Vol.17 No.-

Volatile flavor components of the Korean and the Chinese ginger (Zingiber officinale Roscoe) have been studied in this paper. The accurate characterization of the flavors from the ginger rhizomes was carried out by head space solid phase trapping-solvent extraction (SPTE) and gas chromatography-ion trap mass spectrometry. Predominant compounds of the Korean ginger flavors are zingiberene, β-phellandrene, camphene, β-sequiphellandrene and α-farnesene, whereas those of the Chinese ginger flavors are β-phellandrene, camphene, zingiberene and α-farnesene. In addition, α-pinene, α-curcumene, β-pinene and β-bisabolene are also found as minor compounds of ginger flavors. A new finding in this work is that limonene, β-sesquiphellandrene, germacrene D, and zingiberene are critical index to distinguish the origin between the Korean ginger and the Chinese ginger.

Dong-Chun Lecture : Cell-based High Content Screening (HCS) for action modes of drug targets by using systematic deletion mutants of Schizosaccharomyces pombe

( Dong Uk Kim ),( Im Seon Woo ),( Mi Sun Won ),( Young Joo Jang ),( Kyung Sook Chung ),( Han Oh Park ),( Hyang Sook Yoo ),( Kwang Lae Hoe ),( Doo Sik Kim ) 한국생화학분자생물학회 (구 한국생화학회) 2005 생화학분자생물학회 춘계학술발표논문집 Vol.2005 No.-

Panipenem을 포함한 Carbapenem 계열 항생제의 몇 가지 임상균주에 대한 시험관내 항균력

이동건,김명신,강진한,전혜선,최수미,위성헌,김상일,최정현,유진홍,신완식,강문원 대한감염학회 2003 감염과 화학요법 Vol.35 No.2

목적 : Panipenem은 일본에서 개발된 카바페넴계 항생제로 그람양성균, 그람음성균, 혐기균에 이르기까지 광범위한 항균력을 나타낸다고 보고되고 있지만 국내에서 분리되는 균주에 대한 감수성 검사결과는 아직 없다. 본 연구에서는 임상에서 분리된 E. coli, K. pneumoniae, P. aeruginosa, S. pneumoniae 균주를 대상으로 carbapenem 계열 및 몇 가지 항생제와 감수성을 비교하고, 특히 P. aeruginosa의 경우 carbapenem의 효과를 Muller-Hinton agar (MHA)가 반감시킬 수 있는 특성을 고려하여 감수성에 변화가 있는지 확인하고자 하였다. 방법 : 2002년 3월부터 6월까지 가톨릭대학교 성모병원, 강남성모병원, 성가병원, 성모자애병원, 성빈센트병원에서 분리된 임상균주 E. coli, K. pneumoniae, P. aeruginosa, S. pneumoniae를 대상으로 하였다. 항생제 감수성 검사는 NCCLS 기준에 따랐고 P. aeruginosa의 경우 MHA 이외에 minimal agar Davis (MAD)를 추가로 사용하였다. 감수성 결과 해석시 panipenem은 imipenem과 같은 기준을 적용하였다. 결과 : E. coli, K. pneumoniae, P. aeruginosa는 각각 100균주였고, S. penumoniae는 134균주였다(PSSP 41, PNSP 93균주). E. coli, K. pneumoniae는 모든 균주가 imipenem, meropenem, panipenem에 대해 감수성을 보였다. P. aeruginosa의 경우 imipenem, meropenem, panipenem, ceftazidime의 MIC_(90)은 각각 16, 8, 32, 64㎍/mL이었다. MHA와 MAD 배지를 이용하여 P. aeruginosa에 대한 항생제 감수성을 비교해 본 결과 imipenem, panipenem의 MIC_(90)가 각각 16, 32㎍/mL에서 8㎍/mL로 감소하였고, imipenem에 비해 panipenem이 더 많이 감소하였다. S. pneumoniae의 경우 PSSP는 imipenem, meropenem, panipenem에 대해 모두 내성이 없었고 PNSP는 imipenem, meropenem, panipenem에 대한 MIC_(90)가 각각 1, 2, 0.25㎍/mL이었다. 결론 : 결론적으로 panipenem은 E. coli, K. pneumoniae에 대해 기존의 카바페넴계 항생제와 유사한 우수한 항균력을 보였다. P. aeruginosa의 경우 ceftazidime, imipenem과 비슷한 항균력을 보였고 아미노산 함량이 적은 배지를 사용함에 따라 MIC가 낮아졌으며 imipenem보다 더 많은 영향을 받았다. S. pneumoniae의 경우 특히 PNSP에서 기존의 카바페넴계 항생제보다 우수한 항균력을 보였다. Panipenem은 주요 그람음성균 및 폐렴연쇄구균 감염에 유용할 것으로 기대된다. Background : Panipenern (PAPM) is a new carbapenern which has an enhanced broad spectrum against both gram-positive and negative organisms. The aim of study was to compare the activities of PAPM with those of imipenern (IMPM), meropenern (MRPM) against several clinical isolates in Korea. Methods : We tested the in vitro antimicrobial activities of PAPM, IMPM, and MRPM against total 300 clinical isolates of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa and 134 Streptococcus pneumoniae collected from 5 different university hospitals. Using NCCLS guidelines, MICs of PAPM, IMPM, MRPM, and/or ceftazidime were determined. Results : All isolates of E. coli and K. pneumoniae were susceptible to PAPM, IMPM and MRPM. MIG_(90) of PAPM, IMPM, and MRPM against P. aeruginosa were 32, 16, and 8 ㎍/mL, respectively. Comparing Mueller-Hinton agar (MHA) and minimal agar Davis (MAD), the MIG_(go) of PAPM and IMPM were reduced from 16 and 32 ㎍/mL to 8 and 8 ㎍/mL, respectively. PAPM was more influenced by MAD than IMPM. All isolates of penicillin susceptible S. pneumoniae showed 0% of resistance to the carbapenems tested. MIC_(90) of PAPM, IMPM and PRPM against penicillin non-susceptible S. pneumoniae were 0.25, 1 and 2 ㎍/mL, respectively. Conclusion : Panipenern could be one of the potentially useful drugs for the treatment of infections caused by E. coli, K. pneumoniae, and S. pneumoniae. We also showed that PAPM had good anti-pseudomonal activity when examined in MAD, the amino acid-limited media. Therefore, it could be useful for the treatment of infections caused by P. aeruginosa.

In situ FTIR과 질량분석기를 이용한 반응 메카니즘 연구

이동근,김둘선,유창무 慶尙大學校生産技術硏究所 1994 生産技術硏究所論文集 Vol.10 No.-

구리촉매에서 메탄올 분해 메카니즘은 in situ FTIR과 MS로서 조사하였다. in situ FTIR과 MS는 메카니즘 연구에 뛰어난 장치이므로 메탄올분해 메카니즘을 in situ FTIR과 MS결과에 근거해서 제의했다.

정상인에서 베타3-아드레날린 수용체 유전자의 변이가 복부 비만도 및 지질대사에 미치는 영향

김영선,윤석기,김철희,서교일,김학선,김극배,변동원,유명희 순천향의학연구소 1998 Journal of Soonchunhyang Medical Science Vol.4 No.1

The β₃-adrenergic receptor is expressed in visceral adipose tissue in humans and is thought to contribute to the regulation of the resting metabolic rate and lipolysis. We studied the influence of a mutation in the β₃ -adrenergic receptor gene(Trp64Arg) on body fat distribution, central obesity, lipid metabolism in 65 healthy young male adults. One out of 65 subjects were homozygous (Arg/Arg) for the trp64Arg mutation, 17 subjects were heterozygous (Trp/Arg), and 47 lacked the mutation(Trp/Trp). The body weight, height, body mass index, waist-to-hip ratio were similar between the subjects with- and without the mutation. Total body fat, abdominal fat amount, body fat distribution, serum total- and HDL-cholesterol, triglyceride, glucose, and insulin concentrations were also not different according to the presence or absence of the mutation. These results suggested that Trp64Arg mutation in β₃-adrenergic receptor gene is not a major contributing factor for central obesity or change in lipid metabolism in Korean young adults.