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      • KCI등재

        염산용액에서 PC88A에 의한 Sm의 용매추출

        이만승,이광섭,이진영,김성돈,김준수 대한금속재료학회 2004 대한금속·재료학회지 Vol.42 No.10

        Solvent extraction experiments of Sm were performed from chloride solution with PC88A and saponified PC88A. Solvent extraction reaction of Sm with PC88A and the corresponding equilibrium constant were evaluated from the experimental and ionic equilibria data as follows Sm^(3+)_(aq)+ 1.5H₂A_(2,org)= SmA_(3,org)+ 3H^(+)_(aq) , K = 0.33. The predicted distribution coefficients of Sm agreed well with the experimental results. The distribution coefficients of Sm with saponified PC88A and the values of equilibrium pH depended on the initial extraction conditions. When the concentration of PC88A was in excess of that of Sm, saponification of PC88A greatly enhanced the extraction of Sm. (Received June 21, 2004)

      • KCI등재

        산마늘로부터 단리한 kaempferol과 quercetin의 콜레스테롤 저하 활성

        이성숙,문서현,이학주,최돈하,조명행 한국목재공학회 2004 목재공학 Vol.32 No.1

        식용 임산자원인 산채류를 기능성 식품으로 개발하고자 산마늘을 비롯한 충 13종의 에탄을 조추출물에 대한 콜레스테롤 저하활성을 검정하였다. 즉, 콜레스테롤 생합성 과정 초기에 관여하는 3-hydroxy-3-methylglutaryl coenzyme A reductase(HMG-CoA reductase)와 후기에 관여하는 squalene synthase의 효소 활성을 조사한 결과 산마늘 잎 에탄올 추출물이 두 효소의 활성을 공히 70% 이상 저해하여 활성이 가장 우수한 것으로 나타났다. 그리고 이러한 콜레스테롤 저하활성과 관련이 있는 물질을 탐색하고자 산마늘로부터 물질 단리를 시도하여 디클로로메탄 가용부로부터 kaempferol과 quercetin을 단리하였다. 또한 유전자 레벨에서의 콜레스테롤 저하 활성을 조사하기 위해 단리물질과 분획물을 C100세포(햄스터 유래 HMG-CoA reductase 고발현 세포주)에 각각 5㎍/㎖과 10㎍/㎖로 24시간 처리하여 HMG-CoA reductase와 squalene synthase의 mRNA 발현 정도를 조사하였다. 그 결과 10㎍/㎖로 kaempferol과 quercetin을 처리한 경우 두 효소의 mRNA가 전혀 발현하지 않는 것으로 나타나 유전자 레벨에서의 콜레스테롤 생합성 저해 효과를 확인할 수 있었다. 이상의 결과 산마늘 잎 에탄올 추출물은 콜레스테롤 생합성에 관여하는 HMG-CoA reductase와 squalene synthase의 활성을 저해하며 이러한 활성 저해 효과는 kaempferol과 quercetin에 기인하는 것으로 사료되었다. 특히 kaempferol과 auercetin은 여러식물의 성분으로서 이미 알려진 화합물이지만 콜레스테롤 저하활성이 있는 것으로 밝혀진 것은 이번이 처음으로 금후 이들 물질과 이들 물질을 함유하고 있는 식물 활용에 필요한 자료를 제공하였다고 사료된다.

      • KCI등재
      • 카드뮴 첨가된 α형 산화철에 의한 일산화탄소의 촉매산화 반응연구

        이성한,김용록,김돈,정원양,김규홍,최재시 연세대학교 자연과학연구소 1983 學術論文集 Vol.11 No.-

        α형 산화철에 카드뮴을 4mol%, 8mol% 및 12mol%로 각각 첨가시켜 외성영역의 특성을 갖는 산화물들을 제조하였다. 이 산화물들을 촉매로한 일산화탄소의 산화반응 속도론적 연구를 통하여 본산화물의 결함구조, CO 산화반응에 대한 촉매성 및 불순물 첨가효과등을 조사하였다. 또한 450℃에서 O_2 및 CO를 여러압력으로 도입시켜 Cd-doped α-Fe_2O_3의 전기전도도를 측정하고 이를 반응속도론적 데이타와 결부시켜 본산화물상에서 CO 의 산화반응 메카니즘과 율속단계를 제안하였다. 반응온도범위 350~460℃에서 산출된 활성화에너지는 10.1~11.3kcal.mol^-1이었다. CO_2흡착에 의한 CO산화반응의 억제효과는 본실험의 반응온도 영역인 350~460℃에서는 나타나지 않았으며 CO 산화반응의 전반응속도 차수는 1.5차로서 일산화탄소에 대해서는 1차, 산소에 대해서는 0.5차임이 밝혀졌다. 반응속도론적 데이타와 전기전도도 데이타에 의해 본촉매의 활성은 카드뮴도프로 인해 생성된 산소공위(Vo"-2e^-)에 기인한 것이었다. 카드뮴의 첨가량이 증가할수록 반응속도는 증가하였으나 12mol% 이상의 카드뮴이 첨가된 산화철상에서는 반응속도가 크게 증가하지 않는 것으로 나타났다. CO와 O_2는 근본적으로 화학흡착하며 CO의 흡착자리는 격자산소(O^-2_(latt))와 기흡착원산소 (O^-_(ads)), 그리고 O_2의 흡착자리는 산소공위(Vo"-2e^-)로 밝혀졌다. The α-Ferric oxide containing 4, 8, and 12mol% with cadmium were prepared. The oxidation rates of carbon monoxide in the presence of these oxide systems were measured to investigate the defect structure, the catalytic activity for the oxidation of carbon monoxide, and the impurity effect. The conductivity was also measured at 450℃ under the various pressures of oxygen and carbon monoxide. From the agreement between the kinetic and conductivity data, the oxidation mechanism of carbon monoxide and the rate determining step on this oxide catalyst were suggested. In the temperature range from 350 to 460℃, the calculated activation energy for the CO oxidation over Cd-doped α-Fe_2O_3 systems were 10.1∼11.3kcal·mol^-1. The inhibition by an adsorbed CO_2 during the CO oxidation was not observed in the above temperature range. The overall reaction order for the CO oxidation is 1.5; the first order with respect to CO and the one-half order with respect to O_2. The catalytic activity of this oxide system is due to oxygen vacancies induced by Cd-doping. The oxidation rates increase with increasing the amount of dopant and above 12mol%, however, don't highly increased. CO and O_2 are essentially chemisorbed as ions and the adsorption sites for CO are the lattice oxygens (O^2-_(latt)) and prechemisorbed oxygens (O^-_(ads)), the adsorption site for O_2 is the oxygen vacancies (Vo¨-2e^-).

      • 위 유문동 평활근세포의 Caffeine 활성화 전류에 미치는 Ascorbate의 효과

        이무열,방효원,엄대용,이상돈 중앙대학교 의과대학 의과학연구소 1992 中央醫大誌 Vol.17 No.4

        In order to observe the effects of ascorbate on the background current in pyloric circular smooth muscle cells, caffeine of which action was fairly clarified, was used to induce the current systems. To block all of the known currents, various blocking agents were added in the external bathing solution. A part of pyloric circular muscle tissue was excised out, and enzymatic isolation technique was used to obtain Ca^2+ -tolerant single circular muscle cells. The whole cell mode of patch-clamp experiment was conducted. The results were as follows : 1. Ascorbate induced the increase of inward currents in the hyperpolarized potential ranges, and quite a large increase of outward currents in the depolarized ranges. 2. Caffeine also induced similar results, but the magnitude of outward current was smaller than that of assorbate in the depolarized ranges. 3. These phenomena were disappeared by addition of the anion channel blocker. 4. Replacement of external NaCl with NMG·Cl was rarely affected the effects of ascorbate and and caffeine. But the effects of ascorbate and caffeine were almost abolished when sxternal Cl^- was substituted for aspartate. These results suggested that ascorbate affected chloride current which thought as a component of the background currents in the pyloric circular smooth muscle cells.

      • APT 골조공사의 공기주도 작업파악에 관한 연구

        이두진,박찬돈,이상관 경운대학교 산업기술연구소 2001 産業技術硏究論文誌 Vol.3 No.2(B)

        The purpose of process planning is to minimize the total duration of building construction. Multi-site scheduling method is one of the solutions of it. But, to use the Multi-site scheduling method, we must synchronize the time of each job. For this reason, Building Structure must be limited. In this paper, put into a formula to calculate the scheduling in the case of Multi-Building Construction without the limitation of the structure. Thus this paper are studied with the view of observation under the condition of the process and the term of works that it is increased a team of the longest works.

      • 개국약사들의 환경 문제에 대한 의식 분석 : The Subject of Studies in Pusan & Ulsan Areas 부산 ·울산 지역을 대상으로

        이상준,정거돈 부산대학교 환경문제연구소 1994 環境硏究報 Vol.12 No.-

        The rapid increase of the population, the urban concentration and the high growth of the industrial development produced the environmental pollution, destroyed the balance of the natural ecosystem, falled in human's circumstances. They are influenced the serious problem that the whole human race should face. Especially in case of my country, establishing five-year economics development since 1960, we promoted the plan. To the conclusion, we could be satisfied in some degree economically. But we overlooked over the damage of the environmental pollution. According to the quality of the surroundings get feeble damage of natural ecosystem and the pollution of our living environments. So we recognize the environmental pollution as the serious social problem. On this point of view, on the premise that our pharmacists as the special intellectuals are responsible for the environmental pollution. Here upon I posed questions and examined the interest of the phamacists about the environmental problem. As follows if I summarize the total contents. 1. About the environmental pollution of my dwelling place, most of us suffer damage and we are the assaulters of it. In particular the dwellers of the factory districts are damaged much. 2. As the media for the acknowledgement about the environmental pollution and the acquirement of recognition, most of pharmacists get acknowledgement printing media about environmental pollution. Accordingly they need the special education about the environmental pollution. 3. We cannot confine the responsibility of the environmental pollution to individual. I should emphasize the public obligation. As and individual, enterprises, a government, so on we all citizens feel emphasize about environmental problem. We already know the importance of duty about it. On the other hand, we practice unsatisfactorily in our daily lives. So the intellectuals should pay mere attention to it. 4. Posing questions about the protestation of the opinions against the environmental pollution and taking exception to it. Most of respondents said "No experience". In spite of their discontent about it, they didn't cope with the positive solutions. Also the low rate of the participation in Environment Purification Movement is caused by the working conditions of the from opening pharmacists is considered (Working time ; Daily Average about 15 hours). To these conclusions, the pharmacists so called the special intelligents need the education about the environmental pollution. As the main group of the Environment Purification Movement, household the enterprises, a government all of us ought to have the reform of conciousness for the public duties. We should introduce better program that gives warning to the environmental pollution in the press, not temporarily but persistently. We demands the practical Environmental Policy about the people's demands for the living in delightful circumstances.

      • 양어용 사료첨가제로서 감귤발효액(EM-Fermented Orange)의 항산화특성

        이준백,문상욱,이영돈,고유봉 제주대학교 해양연구소 2000 해양과환경연구소 연구논문집 Vol.24 No.-

        Mandarine orange (Citrus unshiu Marc.) only added with sugar was fermented by effective microorganisms (EM) called "EM-fermented orange". EM was mainly composed of lactic acid bacteria, phototrophic bacteria and feast. As pH of EM-fermented orange reached 3.5 to 4.0 in the course of fermentation, the incubation was stopped. and then. EM-fermented orange was preservable at room temperature for about 6 months. Composition and concentration of free amino acids in EM-fermented orange were analyzed. Concentration of total amino acids was 167mg/l, and the relative content of carnosine (β-alanyl-L-histidine) which was well known as a kind of antioxidant materials was very high. 41%. In addition. crude extract showing antioxidant activity could be obtained from EM-fermented orange using some organic solvents. The antioxidant activity of the crude extract was equivalent to about 9% of that of vitamin E by the use of 1.1-diphenyl-2-picrylhydrazyl (DPPH) method. It was suggested that EM-fermented orange having antioxidant characteristics could promote the health of fish.

      • 한국인 심부전증 환자 심근에서의 인형 거대 세포 바이러스 감염

        이명용,이무용,김영권,한성식,최성준,김효수,이영우,서정돈 단국대학교 1998 論文集 Vol.33 No.-

        Objectives: In order to evaluated the prevalence and the site of infection of cytomegalovirus in terminally failing heart, cytomegaloviral DNA was detected in the explanted hearts of transplantation recipients. Methods: DNA extractions were performed from explanted failing hearts(N=22) and normal hearts(N=5) and polymerase cain reactions(PCRs) were done for detection of late gene sequence coding pp150 glycoprotein. The products were confirmed by electrophoresis on the 1% agarose gel. n order to improve the detectability of cytomegaloviral genome, nested PCRs were executed with the primers designed for the original 607 bp products. In situ PCRs also were done with the samples which were confirmed as positive for CMV viral genome by nested PCRs. Results: All patients had IgG anti-cytomegalovirus antibody and did not have IgM anti-cytomegalovirus antibody. Cytomegaloviral genomes in myocardium were detected by polymerase chain reaction. The 607bp products by PCRs were found in both explanted failing heart(3 cases/22. 13.5%) and normal hearts( 1 case/5, 20.0%). In nested PCRs, 186bp products were found in both failing hearts(LV 4/22, LA 3/2, RV 4/22, RA 0/17) and normal hearts(LV 2/5, LA 1/4, RV 2/5, RA 2/5). These was no significant change in positivity of cytomegaloviral DNA genome between failing and normal hearts. Total positivity of cytomegaloviral genome in explanted hearts was 44.4% according to the nested PCR results. The positivity of cytomegaloviral DNA by n situ PCR was 33.3%(4/12), and the site of positive reaction was the nuclei of the myocardial cells. Conclusion: Cytomegalovirus was rarely observed in explanted hearts of terminal heart failure and nested PCR could enhance the sensitivity of cytomegaloviral genome detection. The result of the in situ PCR showed the site of the cytomegaloviral infection was nuclei of the myocardial cells. Cytomegalovirus, however, might have no direct causal relationship in the development of terminal heart failure.

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