수분에 불안정한 2-(Trimethylsilyloxy)furan의 수용체에서의 카르보닐 부가반응 연구

柳燦模,李宗昊,李晟洙,尹淑卿 성균관대학교 기초과학연구소 1995 論文集 Vol.46 No.2

The irreversible addition of 2-(trimethylsilyloxy)furan to various aldehydes in the presence of catalytic amount of alkali metal carbonate in aqueous media is described. Even though alkli metal enolates have many synthetic advantages of applicability and high selections of (E)- and (Z)- enolate geometry, their application to carbonyl addition have been utilized in limited purpose mainly due to the low stereoselectivity resulted from the equilibrium between retroaldol and realdol. The addition of 2-(trimethylsilyloxy)furan to the aldehyde in the presence of K_2CO_3 in aqueous media(THF : H_2O = 9 : 1) at -20℃ resulted in the formation of addition product in high yield and moderate good stereo selection (3-15:1).

TEMPOL(??)에 대한 전자 스핀 공명 연구

유홍용,한찬수 순천향대학교 기초과학연구소 1999 순천향자연과학연구 논문집 Vol.5 No.1

Electron spin resonance studies of the free radical TEMPOL have been carried out at room temperature. The ESR spectra have 3 hyperfine lines due to interactions with the nuclei of nitrogen of the radical. As results of our analysis, the ESR parameters have been found that ??, ??. From the hyperfine interaction with a nucleus of nitrogen, it is suggested that the magnetic electron in the radical is localized around the nucleus.

부분입체선택적 Zwitterionic Claisen 전위반응

柳燦模,崔夏洵,李宗昊,鄭元爀 성균관대학교 기초과학연구소 1995 論文集 Vol.46 No.2

Aza-Claisen rearrangement through the zwitterionic intermediate is described. This reaction was able to carry out at low temperature(-78∼0℃) and also exhibited high diastereoselectivities. The formation of zwitterionic intermediate was realized by addition of t-crotylamine to the ketene formed from deprotonation of corresponding acyl halide. The electronically neutral product was achieved through the [3,3]-sigmatropic rearrangement of self-promoted zwitterionic intermediate in high diastereoselectivity due to lower reaction temperature. Treatment of N-crotylpiperidine with propionyl chloride in the presence of K_2CO_3 at 0℃ for 1 h gave threo selective(97 : 3) amide in 41% isolated yield.

새로운 [3,3]-Sigmatropic Rearrangement를 이용한 입체선택적 아미드의 합성

柳燦模 성균관대학교 기초과학연구소 1993 論文集 Vol.44 No.2

새로운 [3, 3]-sigmatropic rearrangement를 통한 효율적인 입체선택적 amide 합성경로를 개발하였다. 키틴과 3차알릴아민의 부가물의 전위로 97:3의 입체선택적으로 amide가 생성되었다. 이 방법론은 비고리화합물의 입체선택적 합성에 넓은 응용성과 효율성을 나타내었다. A diastereoselective synthetic route to amide through novel [3, 3]-sigmatropic rearrangement has been developed. Rearrangement of adduct between ketene and t-allyamine afforded amide with 97:3 diastereoselection. The method exibited wide applicablity and efficacy for the stereoselective synthesis of acyclic system.

女子中ㆍ高等學生의 服飾行動과 服裝規範에 대한 硏究 : 學校에서의 服裝規定을 中心으로 Focusing on Clothing Regulations in the School

유덕화,박찬부 한국 가정과 교육 학회 1991 한국가정과교육학회지 Vol.3 No.-

The purpose of this study was to investigate the following contents ; 1. Relationship between clothing behavior (modesty, conformity, importance) and clothing regulations of school girls. 2. The differences between middle school girls and high school girls in clothing behavior and in attitude toward clothing regulations. 3. The differences between stuendts gerself norms and subjective norms (the students thoughts which would be parents opinions and teachers opinins) in attitude toward clothing regulations. Questionnaires were designed and administered to 300 middle school girls and 302 high school girls in Inchon. The obtained data were statistically analyzed by Pearson's correlation coefficients, t-test, F-test, and Duncan test. The results of the study were summarized as follows; 1. As tho the differences in responses between school levels, the high school girls showed higher interest in conformity. But there is on differances in Modesty and Importance by school levels. 2. As tho the differences in responses between school levels, there were on differences in attitued toward clothing regulations. But according by types of clothing regulations, high school girls showed higher desired in shoes and sack. 3. In correlation coefficients between the variables on clothing behaviors and the attitudes toward clothing regulations of school girls, modesty is the most related toward clothing reguations of school girls and conformaity, importance the next. The higher the school girls are in modesty, the more follow the clothing reguations. And the higer the school girls are in conformity and importance, the lower follow the clothing reguations. 4. The differences between students herself norms and subjective norms (the studenst thoughts which would be parents opinions and teachers opinions), students and parents showed lower scores than teachers. That is tho say, theachers put more restrictions on students clothing than parents do.

「단종애사」연구

최유찬 연세대학교 국어국문학과 1984 연세어문학 Vol.17 No.-

마찰력과 열처리에 따른 아크용사 및 아크용접된 Fe-Cr-B 합금 피복층의 변화

이찬규,유인석,김강형,구본흔,박맹로 國立 昌原大學校 産業技術硏究所 1995 産技硏論文集 Vol.9 No.-

Variations of arc thermal sprayed and arc welded Fe-Cr-B alloy coating with frictional loading and heat treatment were investigated by means of X-ray diffraction, optical microscopy, scanning electron microscopy, electron probe microanalysis and hardness test. The as-coated layers were shown to be crystalline state but peaks with the frictional loading largely disappeared in X-ray diffraction profiles. The splat is relatively wavy with the boundary in arc thermal spray coating. After heat treatment, the amount of porosity was found to be decreased and the intersplat distance was increased. As annealing temperature increased, interface layer for arc welding coating increased by the diffusion of Cr atoms. The wear type observed in arc thermal spray coatings is splat delamination. The hardness of the arc thermal spray coation layer was superior to that of the arc welding layer. Hardness of coated layer is reduced and microstructures become to be uniformed by the heat treatment.

靑色 슬라이드 製作法

徐贊基,朴裕哲,李俊石 경북대학교 과학교육연구소 1985 科學敎育硏究誌 Vol.9 No.-

Blue slides have been widely used in many fields such as education, science, business and administration. However, because the method of blue slide production is preserved secretly, the diffusion of know-how of making up blue slides is checked and the users had to pay expensive cost to get them in spite of relatively cheap cast and simple procedure of making them. This study puts the purpose to develop a new know-how which uses easily and cheaply available materials and has so simple procedure for non specialists to make the slides easily. The major findings are as follows. (1) It is desired to make toning solution which can be prepared from ferric ammonium citrate, oxalic acid and potassium ferricyanide. (2) As for these components, the proper masses of the components of the solution per liter are 6 grams respectively. (3) 6 minutes are required for effective toning. (4) 3-5% sodium bicarbonate solution is at an optimum condition to clean the letters.

An MO Studies on Reaction Mechanism and Reactivity of β-Chloro Difluoro Ethyl Methyl Sulfides, Sulfoxides and Sulfones

崔燦有,金宜洛,白禹鉉 東國大學校 1976 論文集 Vol.15 No.-

반경험적 분자궤도 함수론인 확장 HU¨ckl 법을 β-Chloro difluoro ethyl methyl sulfides, sulfoxides, sulfones에 적용하여 반응기구와 상대적인 반응속도를 설명하고 n-propyl chloride와 비교 하였다. 계산결과는 실험값과 반응성지수가 잘 일치함을 보였다. A semiempirical molecular orbital theory which is known as extended Hu¨ckel theory is applied to explain the relative reactivity and the reaction mechanism of β-Chloro difluoro ethyl methyl sulfides, sulfoxides, sufones and compared with n-propyl chloride. It has been shown that the calculated MO theoretical reactivity indices are consistent with the experimental order of the reactivity and reaction mechanism.

벤브니스뜨 연구 : 소쉬르의 계승과 극복 Continuation et depassment saussuriens

문유찬 全南大學校 人文科學硏究所 1987 용봉인문논총 Vol.16 No.-

벤브니스뜨는 소쉬르에게서 무엇을 계승하고 극복하려고 했는가? 분과학문으로서 언어학을 정립하기 위해, 벤브니스뜨는 언어학의 연구대상을 개별언어로 설정하고 이 개별언어의 의미작용 기제를 끝까지 추구하려고 하였다. 따라서 언어기호의 체계로서 랑그를 연구하고자 한 소쉬르를 본받아, 벤브니스뜨는 차이의 체계(systeme de différenecs)로서 개별언어를 연구한다. 이 경우 언어의 내재적 원리를 바탕으로 한 언어의 폐쇄성을 극복할 길이 없다. 벤브니스뜨의 일반언어학연구를 지배한 개념은 첫째, 언어의 상징능력(la symbolisation)과 의미작용이다(la signification). 상징능력은 인간과 문화와 사회를 연결하는 고리로서, 학문적으로 문화학-일반기호학 수립의 전제조건이다. 언어학의 분과과학의 테두리 안에서는 의미작용이 조작개념으로 사용된다. 벤브니스뜨에게 이 의미작요이란 본질적인 개념으로, 이는 기술문법이나 변형생문법이 형태구조만 밝힌다고 여겨질 때 이 두 문법을 비난하는 준거가 된다. 기호의 의미와 의미작용을 밝히기 위한 시도의 일환이다. 둘째, 언어의 주관성과 언어의 개인소유화의 개념이다. 인간언어와 언어사용으로서의 담화를 구분하게 되는 것, 그리고 궁극적으로는 발화행위의 이론을 구축하게 되는 것은 이 두 개념의 바탕 위에서이다. 궁극적으로 일반기호학의 수립, 기호론적 영역과 의미론적 영역 각각에 대한 서로 다른 분석도구의 개발, 발화행위이론의 구축, 이 세 가지가 벤브니스뜨가 언어학자로서 이루고자 했던 과업이다. 벤브니스뜨는, 무냉(1975:9)이 평한 데로, 일반언어학자로서는 지나치게 내성적인 언어철학을 기반으로 몇몇 제안을 하는데 그쳤는가? 설령 벤브니스뜨가 소쉬르를 계승・극복하지 못했다고 해도, 벤브니스뜨가 랑그의 언어학에서 담화의 언어학으로 이행하는데 크게 기여한 것은 확실하다.