수용액상의 Fe(EDTA) 착물에 의한 NO 가스의 흡착에 관한 열역학적 연구

방효춘,김성옥,정해영 德成女子大學校 1996 德成女大論文集 Vol.27 No.-

In order to develope the method to remove the water-insoluble pollutant NO? in aqueous solution, metal chelate complex was used. Among the series of metals and chelates, Fe?(EDTA) was the first choice. On this paper, the binding of NO gas to Fe?(EDTA) was monitored through GC and thermodynamic parameters of that reaction was obtained. The equilibrium constants for the the binding of NO gas to Fe?(EDTA) are 1.44×10?M? at 40℃, 2.49×10?M? at 20℃, also△H?=-10.81㎉/㏖ and △S?=-12.00㎈/㏖·K.

혼합용액에서 코발트 화합물의 선택적 용매화 현상(Ⅱ). ??Co-NMR Linewidth에 미치는 Viscosity의 영향과 Chemical Shift와의 관계

방효춘 德成女子大學校 1996 德成女大論文集 Vol.25 No.-

The analysis of changes of linewidth on mixed solvent systems of cobalt porphyrin compounds has been carried out with the treatment scheme of Covington, and the results were compared with the one from the chemical shift data. The application of Deverell's approach indicated that the linewidth data could be more sensitive tool to analyze the solvation behavior.

위 평활근 세포의 활동전압을 이루는 CI^-전류성분에 관한 연구

방효원,이종찬,이무열,엄대용,이상돈 중앙대학교 의과대학 의과학연구소 1993 中央醫大誌 Vol.18 No.3

Chloride current has been known as a part of backgroud current. Recently, its roles in the maintenance of action potential have much attention. The purposes of the present study are clarifying the chloride current component which might play an important role in generation and maintenance of the action potential in the pyloric circular smooth musele cells. We used the whold cell voltage clamp techniques to assess the current and voltage responses induced by caffeine superfusion. The results were as follow: 1. Caffeine superfusion induced the increase of inward currents in the hyperpolarized potential ranges, and the increase of outward currents in the depolarized ranges. 2. Sodium ion removal from the external medium and the addition of cadmium ion rarely affected these current response. 3. Duration of the action potential was elongated by application of the caffeine and modified by the change of the intracellular chloride ion concentraion. 4. The effect of caffeine superfusion on the action potential disappeared by the addition of the anion channel blocker. The results suggest that caffeine superfusion may prolong the duration of repolarized phase of the action potential probably by the chloride current activation in the gastric antral smooth muscle.

집토끼 동방결절부위별 자동능에 대한 CA^(2+)의 효과

방효원,엄대용,이상돈 중앙대학교 의과대학 의과학연구소 1985 中央醫大誌 Vol.10 No.1

Effects of external Ca^2+ on the spontaneous firing rates of the isolated rabbit atria, the whole SA node, and the small strips of SA node at constant temperature were observed and analyzed by recording the transmembrane action potentials. The results were as follows: 1. It has been shown that a positive chronotropic effect in the isolated atrium and whole SA node has appeared at elevated Ca^2+ concentration. 2. On the contrary, negative chronotropic effect of Ca^2+ were observed in a small strip of SA node. 3. The each small strip of SA node could be divided into two kinds of cells, i.e., peripheral pacemaker cells and central pacemaker cells. In central pacemaker cells, Ca^2+ has shown positive chronotropy but opposite effect was observed in peripheral pacemaker cells. 4. The central pacemaker cells of the small strip of SA node could be divided into two groups with. configuration and parameters of action potentials. The two groups showed different degree of positive chronotropic effect respectively with elevated Ca^2+ concentration.

주행차량에 의한 강교량의 충격계수에 관한 연구

김상효,이상호,김방래 연세대학교 산업기술연구소 1996 논문집 Vol.28 No.1

In this study, a finite element program which can perform the dynamic analyses of bridges by considering the interaction forces between the bridge and moving vehicle is developed. The impact factors and dynamic behaviors of bridges according to the various parameters, such as speed and weight of vehicles, span length, damping ratio, girder spacing and transverse stiffnesses of bridges, are studied. The impact factor, in general, increases as the traveling speed increases, whereas the weight of vehicle does not affect the impact factor. The impact factor is larger in exterior girders than in interior girders. As the spacing between two girders increases, the impact factor decreases, and it is also affected by the lateral rigidities of the bridges. In addition, the impact factor is smaller in continuous bridges than in simply supported bridges.

무용전공과 고교 및 대학의 직무수행에 따른 지도가치관 분석

한효림,김영환,조방현 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.4

The purpose of this study was to explore the how the dance education is conducted in high schools and colleges consisting of three dance divisions (Ballet, Modern Dance and Korean Dance) in South Korea, and how different each division is related to its pedagogy. Three dance major high school teachers and three college professors were thoroughly observed and interviewed by the researchers. The study draw following conclusions: First, the high school teachers gave more points to student applicants who had the better body figures and potential physical growth, while university professors gave more points to student applicants who had more skills and sincerity. Second, there were no differences in their educational philosophy and value between high school teachers and college professors, Third, all participants of this study indicated that there is a serious problem in dance area, More and more students are likely to choose schools according to the fame of schools, not to their interests and specialties.

한국산 뱀독이 개구리 심방근 수축에 미치는 효과

한종희,방효원,엄대용,이상돈 중앙대학교 의과대학 의과학연구소 1984 中央醫大誌 Vol.9 No.1

In order to observe the effect of freeze-dried saliva of Korean venomous snake, Agkistrodon blomhoffii brevicaudus, on the contractility of spontaneously beating frog atrial muscle, a muscle strip was prepared and immersed in a vertical force recording chamber in frog Ringer solution containing 10^-7M propranolol. Isometric contraction was recorded and the following results wers obtained. 1. Developed tension of an atrial muscle strip increased with the increase of external calcium ion concentration, from 0.66mM up to 3.3mM but little change was observed in spontaneously beating frequency. 2. Inverse relationship was observed between the contractility and its driving frequency in venomtreated group. 3. The contractility decreased slightly in high(16∼32㎍/m㎖) venom concentration group but the beating frequency showed no definite correlation with the venom concentration. The above results suggested that Korean snake venom inhibited the influx of calcium ion across cell membrane to reduce the contractility like that in a ventricular muscle cell although the degree was slight.

동방결절의 부위별 전기적 특성에 미치는 Higenamine의 효과

조규석,방효원,조성일,엄대용,이상돈 중앙대학교 의과대학 의과학연구소 1986 中央醫大誌 Vol.11 No.2

The effects of higenamine on the membrane potential of the central and peripheral areas of the rabbit sino-atrial node which were two small electrically insulated partitions, 0.5X0.5mm in sizes were recorded by 3M KCl-filled glass microelectrodes. The following results were obtained: 1. In the central and peripheral areas, the spontaneous firing frequencies were all increased with the increment of the higenamine concentration from 5X10^-8M/L to 10^-6M/L. 2. Higenamine showed positive chronotropy in the central and peripheral areas which were different to those in the high outside calcium concentrations. 3. After pretreating the preparations with 5X10^-7gm/m of tetrodotoxin(T.T.X.) which revealed the reduction in spontaneous firing frequency maximum diastolic potential(M,D.P) and overshoot, higenamine restored the frequency in the central area and the notch of the overshoot in the peripheral area. The above resu1ts could be regarded that higenamine showed some findings of enhanced sodium current although it would not be so specific in the effects to the ionic currents underlying the spontaneous firing frequencies in the rabbit sino-atrial node.

위 유문동 평활근 세포의 전기적 활동에 미치는 Vanadate의 효과

유중배,방효원,엄대용,이상돈 중앙대학교 의과대학 의과학연구소 1990 中央醫大誌 Vol.15 No.1

Effects of vanadate on the resting membrane potential and slow waves of the circular smooth muscle were observed using glass capillary microelectrodes. The obtained results were as follows: 1. Vanadate did not show any effects on; the slow waves of spontaneously beating preparations. 2. Variation of the resting membrane potential due to the change of outside K^+ was 20-28m V/decade which suggested the significant contribution of Na^+ to maintain the resting membrane potential. 3. Vanadate did not show any further effects on the depolarized state about l0mV by outside 20mM K^+. 4. Vanadate induced the depolarization in the low outside K^+ condition and the effect was exaggerated when Cal^(2+) was depleted. 5. Vanadate induced the depolarization in the low Na^+ and K^+ condition. It was conjectured that the effects of vanadate were enhancing the voltage-dependent calcium.

한국산 뱀독이 개구리 심실근육세포의 수축력과 활동전압에 미치는 영향

한형일,방효원,엄대용,이상돈 중앙대학교 의과대학 의과학연구소 1984 中央醫大誌 Vol.9 No.3

In order to observe the effects of freeze-dried saliva of Agkistrodon caliginosus and Agkistrodon saxatilis, the Korean poisonous snakes, on the contractility and action potential of frog ventricular muscle cells, the isometric tension in a vertical chamber and the action potential in horizontal chamber were recorded and analyzed. The following results were obtained; 1. ED_50, to reduce the contractility was 4-8ug/ml in the case of A. saxatilis and 8-16ug/ml in the case of A. caliginosus which all were higher than that of A. brevicaudus and the inhibitory effect on the contractility was greater in the case of A. saxatilis than that of A. caliginosus. 2. In the case of A. saxatilis, APD_50(time to repolarize 50% of action potential amplitude) decreased from 820±80 ms to 710±60 ms, the overshoot and the V max(Maximum depolarization rate) decreased from 34±8 mV to 18±4 mV, from 98±8 V/s to 89±4 V/s respectively. 3. In the case of A. caliginosus, ADP_50 decreased from 880±70 ms to 720±40 ms, the overshoot and the V max decreased from 28±6 mV to 20±4 mV, from 89±8V/s to 77±12V/s, respectively. 4. Inhibition of contractility and overshoot potential were more prominent in A. saxatilis and APD_50 was more decreased in A. caliginosus. The above result showed that Korean snake venoms would decrease the ionic current underlying the rapid upstroke phase and slow inward currents by calcium ions simultaneously in a frog ventricular muscle cells.