혼합용매의 비직선형 용매화 에너지 상관관계

嚴泰燮,成大東,李鍾八,朴現錫,金良姬 東亞大學校 大學院 1989 大學院論文集 Vol.14 No.-

Solvoltic rates for 1-adamantyl chloride and 1-adamantyl bromide were determined for methanol-mitromethane and methanol-nitrobenzene. Solvent ionizing power was estimated for two mixtures. Two solvent mixtures were shown that uncleophilic solvent assistant was in relation to the general use of the Grunwald-Winstein equation. Also, there is no evidence to support ail earlier suggestion that 1-adamantyl derivatives are procedeed by S( )1 absolutely, wherein they can be interpreted as evidence for dessociative S( )2 from the results of double difference method and Berry's pseudo rotation process diagram.

理事의 責任과 經營判斷의 原則

姜大燮 한국상사판례학회 2001 상사판례연구 Vol.12 No.-

The business judgement rule is an important defense which, if applicable, reduces the liability exposure of directors to claims for mismanagement and breach of their duty of care. This defense recognizes that not all decisions by directors will result in benefit to the corporation or will appear to be prudent. However, courts will not second-guess business decisions by directors so long as the directors follow appropriate procedures in making decisions. In essence, the business judgement rule provides that courts should not examine the quality of the directors' business decisions, but only the procedures followed in reaching the decision, when determining director liability. This article analyses the case relating to the business judgement rule, and studies whether the rule may be applied to the Korean company law. The article includes i) policy reason for rule, ii) preconditions to application of rule, iii) presumptive effect and rebutting the presumption, and iv) application to special situations. Its conclusion is that the business judgement rule is not peculiar to American law, and Korean case may be based on a similiar position.

N-벤조일-이미다졸 유도체의 가수분해반응

성대동,엄태섭,이종팔,박유미,박현석 東亞大學校 1992 東亞論叢 Vol.29 No.1

The pseudo first order rates for hydrolyses of N-benzoyl-(2,4,5-triphenyl)-imidazole and N-benzoyl-(4,5-diphenyl)-imidazole have been measured by means of spectrometry in over all pH range at 30˚C with the ionic strength of 0.5M KC1. In the case of N-benzoyl-(2,4,5-triphenyl)-imidazole, the general acid catalytic reaction was not observed, while the general base catalytic reaction showed in near the range of pH=7. In the case of N-benzoyl-(4,5-diphenyl)-imidazole, the general acid and base catalytic reaction showed at the regions of less than pH=4 and more than pH=10. The rate constants for pH independent reaction of N-benzoyl-(2,4,5,-triphenyl)-imidazole were shown a little bit faster than those of the corresponding to N-benzoyl-(4,5-diphenyl)-imidazole. The reaction mechanism of pH independent reaction was interpreted by means of thermodynamic parameters, and the isotope effect. The magni-tude of ΔH??, ΔS??, ??/?? values indicated that the bond breaking had been progressed more than bond formation in the transition state.

음이온에 의한 토마토 뿌리조직 마이크로솜 H^+-ATPase 활성 저해

신대섭,조광현,김영기 충북대학교 첨단원예기술개발연구센터 2000 연구보고서 Vol.5 No.-

식물 뿌리세포의원형질막 및 액포막에 위치하는 H+-ATPase들은 세포의 여러 가지 생리활성에 중요한 역할을 수행한다. H+-ATPase의 생리활성 특성을 조사하기 위하여 토마토 뿌리조직으로부터 마이크로솜을 분리하고, H+-ATPase 활성에 미치는 음이온의 효과를 조사하였다. 다양한 종류의 음이온들이 H+-ATPase의 활성을 저해함을 확인하였으며, 이들 중 특히 효소의 저해정도가 다른 citrate와 인산을 선택하여 작용특성을 조사하였다. Citrate에 의한 ATPase 활성저해는 3mM 이상에서 나타났고, 20 mM citrate는 활성을 50-60% 저해하였다. 그러나, citrate,의 저해효과는 MG2+의 농도를 증가시킬수록 감소하여, citrate에 의해 저해된 ATPase 활성은 Mg2+에 의해 회복되는 것으로 나타났다. 즉, 7 mM Mg2+을 첨가하였을 때, citrate에 의한 활성저해는 관측되지 않았고 ATPase 활성은 대조활성과 비슷한 수준으로 회복하였다. 이러한 결과는 citrate가 Mg2+을 chelation함으로써 H+-ATPase의 활성을 저해하기 때문이다. 한편, 인산에 의한 ATPase 활성저해는 3mM 이상의 농도에서 나타났고, 30 mM 인산은 ATPase의 활성을 50% 저해하였다. 인산에 의해서 저해된 ATPase의 활성은 MG2+의 농도증가에 의해 회복되지 않아, 인산에 의한 저해효과는 Mg2+과 무관하였다. H+-ATPases located on plasma and vacuolar membranes play major roles in various cellular physiological processes. In order to investigate the physiological roles of H+-ATPases, microsomes were prepared from tomato roots and the effects of various anions were measured on the activities of H+-ATPases. H+-ATPase was inhibited by various anions. Citrate and phosphate were chosen to investigate detailed inhibitory mechanisms on ATPases since they showed different levels of inhibition. Inhibitory effect of citrate was observed at the concentrations above 3 mM. when 20 mM citrate was added, the H+-ATPase activity was decreased by 50-60%. However, the inhibitory effect of citrate was decreased by increasing the concentration of Mg2+. The citrate-induced inhibited activity was recovered by the addition of Mg2+. Addition of 7 mM Mg2+ completely removed the inhibitory effect of citrate and the activity recovered to the level of the control experiment. These results imply that citrate chelates Mg2+ and thus inhibits H+-ATPases. Meanwhile, the inhibitory effect of phosphate was observed at the concentration above 3 mM and the activity was decreased by 50% in the presence of 30 mM phosphate. Further addition of Mg2+ showed no recovery on the activity. These results imply that the inhibitory effect of phosphate is not dependent upon the concentration of Mg2+. Key words: anion, citrate, phosphate, H+-ATPase, tomato roots Abbreviation: PK, pyruvate kinase; LDH, lactate dehydrogenase; HEPES, N-(2-hydroxyethyl)-piperazine-N'-(2-ethanesulfonic acid); NADH, nicotinamide adenine dinucleotide

Morse Complex의 구조에 대하여

權大燮 건국대학교 1988 論文集 Vol.26 No.1

Let M be a Riemmannian manifold, f be a Morse function on M and ξ be a gradient-like vector field. We can find a newgradient-like vector field ξ1 and a new Morse function f1 such that ξ1 induces stable and unstable submanifolds, Ws, Wu, having transversal intersection with f1 self-indexing. The method and results for the finite dimensional case belong to J. Milnor [2] We use a simple generalization of J. Milnor's results and use these results to define the Morse complex. We wish to study the structures of Morse complex.

Hg^2+에 의한 토마토 뿌리조직 마이크로솜 H^+-ATPase의 가역적 저해

신대섭,조광현,김영기 충북대학교 첨단원예기술개발연구센터 1999 연구보고서 Vol.4 No.-

토마토 뿌리조직의 마이크로솜 ATPase 활성에 대한 중금속의 효과를 조사하기 위하여 뿌리조직으로부터 마이크로솜을 분리하였고, enzyme-coupled assay를 이용하여 마이크로솜 이온펌프(ATPase)의 활성을 측정하였다. 여러 가지 중금속 이온들 중 Hg2+은 마이크로솜 ATPase 활성을 농도 의존적으로 저해하였으며, Gd3+ 과 Fe3+, La3+, Zn2+ 그리고 Pb2+ 등은 마이크로솜 ATPase의 활성을 현저히 저해하면서 동시에 assay에 사용된 효소를 저해하였다. 그러나, CS+과 BA2+은 마이크로솜 ATPase 활성에 영향을 미치지 않았다. Hg2+은 원형질막과 액포막에 위치하는 H+-ATPase들의 활성을 10 μM 이상의 농도에서 급격히 저해하였고, 1 mM 이상의 농도에서 완전히 저해하였으며, 두 효소들에 대한 활성저해의 Ki 값은 각각 80 , μM, 58 μM로 나타났다. Hg2+에 의해 저해된 ATPase의 활성은 DTT의 농도를 증가시킴에 따라 회복되어, HG2+에 의한 ATPase 활성저해는 가역적임을 확인하였다. 이러한 결과들은 Hg2+이 원형질막과 액포막에 위치한 H+-ATPase들을 비선택적이고 가역적으로 저해함을 보여준다. In order to characterize the effects of heavy metal ions on the microsomal ATPase activities, microsomes were prepared from the roots of tomato plant and the activity of microsomal ATPase was measured by an enzyme-coupled assay. Hg2+ inhibited the activity of microsomal ATPase in a dose-dependent manner, while Gd3+, Fe3+, La3+, Zn2+, and Pb2+ inhibited not only the ATPase activity but also the activities of enzymes used in the assay. However, Cs+ and Ba2+ showed no significant effect. Hg2+ inhibited the activities of both plasma membrane and vacuolar membrane H+-ATPases. In the dose-response to Hg2+, the activities of both microsomal H+-ATPases were severely inhibited at the concentration of Hg2+ above 10μM and were completely inhibited at 1 mM Hg2+. Apparent Ki values of Hg2+ on the inhibitions of plasma membrane and vacuolar membrane H+-ATPases were 80 μM and 58 μM, respectively. The Hg2+-induced inhibitions were reversible since the addition of dithiothreitol completely reversed the inhibitory effects of Hg2+.These results suggest that the inhibitory effects of Hg2+ on both plasma membrane and vacuolar membrane H+-ATPases are nonselective and reversible.

술핀아미드의 가수분해반응에 미치는 친핵체의 촉매작용

嚴泰燮,李益春,李鍾八,成大東 東亞大學校附設基礎科學硏究所 1997 基礎科學硏究論文集 Vol.14 No.1

2배위 및 3배위 황화합물들이 가수분해될 때 무기산이나 할로겐화 이온과 같은 친핵체에 의해 촉매작용을 받는다는 사실이 알려져 있다. 이들 화합물들의 산촉매 가수분해반응 메카니즘은 식(1)에서 보는 바와 같이 반응 중심인 황 원자 주위에 다섯 개의 전자쌍이 관련된 초원자가 중간체(hypervalent intermediate)가 관련된다는 사실이 흥미의 대상이 되어 오고 있다.

初等學校 科學敎育課程에 關한 硏究 : Development of Units for 4th, 5th, and 6th Grade

吳岱燮,崔宗洛,李相協,權炳奎,李時雨 慶北大學校 師範大學 1972 敎育硏究誌 Vol.14 No.-

In 1971, units for 4th, 5th, and 6th grade, which are followed by those developed in 1970, have been developed. Those units have been piloted in the Attached Primary School of Gyeong Bug National University, and revised as a result of these trials. They are "Electricity and Matter", "Battery and Bulb", and "Position and Motion" for 4th grade, "Force and Motion", "Absorption of Light", "Microscope and Living Thing" for 5th grade, and "Sun and Seasons", "Current and Magnetism" and "Chemical Phenomena" for 6th grade. Every unit have been designed in such a way that the successful results are to be obtained through children's experimental activities. The achievement of the children's activities have been graded with the test battery developed by the Science Curriculum Research Institute. Generally specking, the children were eager to explore the nature by their own experiments, and they were able to perform the planned experiments with success. The learning activities basing on the inquiry method was effective in cultivating the ability and the attitude toward investigating, and in understanding the nature.

지속적인 운동으로서의 골프가 아마추어 골퍼의 스트레스에 미치는 효과

오대성,송은섭,나정란 圓光大學校附設 生活體育硏究所 2001 生活體育硏究 Vol.11 No.-

This survey for the purpose of finding out the effects of Golf as a continuative exercise on the mental stress has made the following conclusion with the research results having examined the effects by using the stress measuring paper to the subjects of the amateur Golfers consisted of 183 (Male 98 and Female 85) in Chonbuk province. 1. The effects on the total stress levels as a continuative exercise shows that the male subjects (105.96±14.38) is higher than the female (104.05±11.49). 2. In the following stress levels the Golf has the effect showing that the male (19.72) is higher than the female (19.54) in the mental factor, and the male (35.74) is higher than the female (34.82) in the emotional and the anxiety factors. And it shows statistical significance (p=0.79). 3. The effects of Golf as a continuative exercise on the total stress levels according to the subjects' career shows that the group (108.03) whose career is more than 83 months is higher than the group (101.68) whose career is more than 49-82 months. 4. The effects of Golf as a continuative exercise on the mental stress in the following levels shows that the group (20.31) whose career is more than 83 months is higher than the group (18.71) whose career is more than 49-82 months in the mental factor, and the group (28.30) who career is more than 83 months is also higher than the group (25.76) whose career is more than 49-82 months in the physical and mental health factor respectively.

트리플루오르에탄올 混合溶媒系에서 염화나프토일 分解反應의 Sn2轉移狀態 變化

嚴泰燮,成大東,柳俊夏 東亞大學校 大學院 1982 大學院論文集 Vol.6 No.-

The solvolytic rate constants of l-naphthoyl, and 2-naphthoyl chloride in TFE-EtOH and TEF-H₂O binary solvent mixtures have been measured at various temperatures. The rate constants for solvolysis in TFE-H₂O solvent mixtures are observed higher than in TFE-EtOH solvent mixtures. In the transition state naphthoyl chlorides have not peri-hydrogen dffect and also the l value of 2-naphthoyl chloride has lager one, therefore this reaction proceeds SAN reaction mechanism as shown in the potential surface diagram. It is in accord with that the reaction proceeds through the transition state of tetrahedral intermediate. The rate constants in TFE-EtOH solvent mixtures have shown higher in lager content of ethanol.