이중액막에 의한 우라늄(VI)연속추출의 해석

현영진 濟州大學校 産業技術硏究所 1995 산업기술연구소논문집 Vol.6 No.-

The uranium(V1) extraction in the continuous vessel was carried out with the flow rates of continuous and organic phase. The initial concentration of uranium(VI) in the external aqueous phase was 1,000 ppm. The mechanism of batch uranium(VI) extraction through the double liquid membrane mediated by DzEHPA was interpreted by the corrected Advanced Front Model. The continuous uranium(VI) extraction was analyzed by the extraction efficiency due to the above model. The times required for uranium(VI) extraction equilibria decreased with the increase of flow rates in the continuous phase under the constant flow rates in the organic emulsion phase. On the other hand, the times required for uranium(VI) extraction increased with the increase with the increase of flow rates in the organic emulsion phase under the constant flow rates in the continuous phase. Therefore the extent of uranium(VI) extraction decreased with the decrease of the times required for the uranium(VI) extraction equilibria. The main operating variable to increase the uranium(VI) extraction efficiency was proved to be the flow rates of continuous phase. The prediction of the optimum operating conditions for the increase of uranium(VI) extraction satisfied with the decrease of the times required for the uranium(VI) extraction equilibria was necessary for this experiment.

이중액막에 의한 우라늄(VI)연속추출의 해석

현영진 濟州大學校工科大學産業技術硏究所 1995 尖端技術硏究所論文集 Vol.6 No.-

외수상 우라늄(VI)농도를 1,000ppm으로 유지하고 에멀젼 유기상의 유속과 연속상의 유속을 변화시키면서 연속식 추출조에서 우라늄(VI)추출을 수행하였다. 우라늄(VI)이 D₂EHPA담체함유 이중액막에 추출되는 기구는 Corrected Advanced Front Model에 의해 해석되었다. 이 해석기구에 기초하여 연속식 우라늄(VI)추출모델을 설정하여 실험치와 비교하였다. 본 실험범위에서는 연속상의 유속과 에멀젼 유기상의 체류시간이 우라늄(VI)추출효율에 기여하는 조업변수임을 확인하였다. 연속식 우라늄(VI)추출시 에멀젼 유기상 유속을 일정하게 유지하여 연속상 유속이 증가할수록 추출평형에 빨리 도달하였다. 한편 연속상 유속을 일정하게 유지하여 에멀젼 유기상 유속의 증가할수록 추출평형에 늦게 도달하였다. 우라늄(VI)추출평형에 도달하는 시간이 빠를수록 우라늄(VI)의 추출효과가 감소하였다. 우라늄(VI)추출향상에 영향을 미치는 주 정상조업변수는 에멀젼 유기상의 체류시간이 아니라 연속상 유속으로 나타났다. 본 연구에서는 D₂EHPA담체함유 이중액막에의한 우라늄(VI)연속추출시 추출평형에 이르는 시간이 빠르면서 추출효과를 향상시킬수 있는 최적조업조건 추산이 주요과제로 제시할 수 있었다. The uranium(VI) extraction in the continuous vessel was carried out with the flow rates of continuous and organic phase. The initial concentration of uranium(VI) in the external aqueous phase was 1,000 ppm. The mechanism of batch uranium(VI) extraction through the double liquid membrane mediated by D₂EHPA was interpreted by the corrected Advanced Front Model. The continuous uranium(VI) extraction was analyzed by the extraction efficiency due to the above model. The times required for uranium(VI) extraction equilibria decreased with the increase of flow rates in the continuous phase under the constant flow rates in the organic emulsion phase. On the other hand, the times required for uranium(VI) extraction increased with the increase with the increase of flow rates in the organic emulsion phase under the constant flow rates in the continuous phase. Therefore the extent of uranium(VI) extraction decreased with the decrease of the times required for the uranium(VI) extraction equilibria. The main operating variable to increase the uranium(VI) extraction efficiency was proved to be the flow rates of continuous phase. The prediction of the optimum operating conditions for the increase of uranium(VI) extraction satisfied with the decrease of the times required for the uranium(VI) extraction equilibria was necessary for this experiment.

女性 能力 開發을 위한 女性學課程 設置의 提案

玄永學,鄭世華,李男德,李效再 이화여자대학교 한국문화연구원 1976 韓國文化硏究院 論叢 Vol.28 No.-

For the past 20 years, there has been a substantial increase in the percentage of women going to colleges and universities in Korea: the statistics indicate that the male and female ratio changed from 87.3% to 12.2% in 1952 to 73.9% to 26.1% in 1974. Inspite of the increasing trend, some academic observers recently began to voice their opinions against higher education for women on the basis that Korean women, regardless of their education in an occupation or public life. The following trends partially support this opinion. First, the tendency of female students concentrating their major fields on a limited number of specializations, such as teachers' education, language, arts, nursing and medical technology, is a contrasting phenomenon with male students, who are more or less evenly distributed throughout all the areas of specialization as their major fields. Second, the remarkable increase in female labor participation for the past 10-15 years is largely contributed by women in the agricultural sector and manufacturing industries, as the percentage of women with higher education have shown not as much of an increase in the labor market as that of these with elementary level or less education. Furthermore, the percentage of women in professions and managerial occupations which would require college education for qualification toward has decreased from 2% in 1960 to 1.8% in 1970. Thirdly, a survey of Ewha graduates concerning their attitudes toward women's social role and college education presents revealing results of their conservatism and resignation sex equality and occupational roles. These findings certainly contradict the egalitarian principles of modern higher education and human potentials. However, there are now growing trends among female college students, with the awareness of changing sex roles, of taking seriously their future occupations and other social roles in addition to marriage. They are showing a greater concern for developing their potentials for professions and egalitarian roles for society, realizing the need for overcoming socio-cultural limitations as well as personal inertia. These are signs calling for new directions in women's education in Korea by introducing women studies programs which are designed to liberate women from the culturally conditioned state of self-awareness and the traditional status and role.

Nocodazole 투여에 따른 척수신경절세포 미세소관의 변화

박정현,이융창 대한해부학회 1995 Anatomy & Cell Biology Vol.28 No.2

朝鮮後期 建築圖에 表現된 視方式 및 空間槪念 分析

이현식,온영태 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1

The purpose of this study is to find out design concept and formative intention shown on the architectural site configuration in late Chosun Dynasty. During the 18th century, changes in cultural context increased interests in traditional/local and natural aspects. New visions on aesthetic sense might make impact to architectural site configuration and space composition. In particular, among the formative specifics presented in architectural paintings, methods of visualization and spatial concepts are studied, through the comparative analysis with architectural site configuration, formative intention. As a result, the fact that various methods of visualization and spatial concepts are reflected in architectural site configuration is revealed.

고온 자전 반응 합성법을 이용한 NiAl 금속간 화합물의 제조 및 이론적 고찰

이용호,김대현,이종현 弘益大學校 科學技術硏究所 1996 科學技術硏究論文集 Vol.7 No.1

Recently, intermetallic compounds containing aluminum, NiAl offer new opportunities for developing low-density, high-strength. NiAl has been invested as an application of automobile and aerospace industry because of low density and high specific strength. However, the development of nickel aluminide alloys delayed because of their poor ductility and fracture toughness. In this study, we use the Self-propagating High-temperature Synthesis(SHS) to produce NiAl alloys from elemental Ni and Al powder. This process is energy efficient and its product has higher purity than the reactants since the impurities of the reactants vaporize during the high temperature reaction. But the high reaction temperature and the fast reaction speed make it difficult to control the reaction with a reasonable reproducibility of product properties. Since the reaction mechanism is various according to the reaction temperature and propagation velocity could change. Thus it is essential to understand the SHS reaction mechanisms to control the reaction. A mathematical modeling, the ignition temperature distribution predicted by the analytical model was found to be match with experimental results. The effect of processing variables including powder size, compaction pressure, heating rate on the ignition temperature was predicted by the model and the results was found in accord with the measured values. The mechanism of NiAl formation by SHS studied using DTA and reaction furnace. Also, the effects of processing parameters on the homogeneity, densification, and microstructures of the products reacted by SHS. The reacted pellet was analyzed using SEM, optical microscope. Ignition temperature and combustion temperature of the SHS reaction with different heating rates(5,10,30,50℃/min) were measured. As the heating rate increased the combustion temperature increased and the ignition temperature have no change. Also, as the heating rate was increased from 5 to 50℃/min, a slight delay in near the melting temperature of NiAl was observed. Ignition temperature and combustion temperature of the SHS reaction with different powder size were measured. As the powder size(-100mesh~-350mesh) increased, the combustion temperature increased but the igniton temperature has no change.

國內藥草의 抗癌成分硏究 (1) : 馬兜鈴, 石蒜, 三稜, 無花果皮, 碧梧桐皮, 人參 등 70餘種에 對하여

丁明鉉,李敦日,金永洙,朱興珪,劉永鐘,金成鎬,鄭鐘南 朝鮮大學校 1977 綜合論文集 Vol.1977 No.-

Alcohol, water, ether, and petroleum ether extracts of 75 species Korean medicinal plants have been tested for their antitumor activity. Most of the extracts had slight activity only. Some extracts had more pronounced acitivity. For antitumor activity, ddD-Mice of weighing 18-25g were used. 0.2 ml of cell suspension in 0.9% saline-glucose solution containing 10?? ascites tumor cells of either Sarcoma 180, Ehrlich carcinoma was transplanted intraperitoneally into each mouse. The control group animals in a given experiment consisted of 14 mices and the experimental group, 7 mices. The materials to be tested were administered once a day by intraperitoneal injection, commencing the day after tumor transplantation until the test animal died, and then the control group was received only 0.5% carboxy methyl cellulose (CMC). The mean survival time of each group was calculated according to the formula indicated in the protocols of the Cancer Chemotherapy National Service Center. In the antitumor activity screening, extracts had pronounced greater prolongation of survival time (50%-100%) were Aristo-lochia contorta, Lycoris radiata, Scirpus maritimus, Ficus carica, Firmiana platanifolia, Panax ginseng, Piper nigrum among the 75 species. The antitumor screening result were tabulated in Table II.

보의 解析法에 關한 比較硏究

曺英鉉 서울産業大學校 1969 논문집 Vol.2 No.1

상악 절치부-토크에 의한 치아 이동과 응력 분포에 관한 유한요소법적 연구

윤현주,임용규,이동렬,조영수 대한치과교정학회 2005 대한치과교정학회지 Vol.35 No.2

본 연구는 상악 절치부에 active 토크가 가해졌을 경우, 교정력을 직접 받은 치아와 인접 치아의 반응을 알아보고자 상악 치아 및 치조골의 유한요소 모델을 제작하고, stainless steel, NiTi, TMA 세 종류의 각형 호선을 육면체 요소로 모델링하여 유한요소 모델을 완성하였다. 호선이 브라켓에 삽입되었을 때 브라켓에 발생하는 반력과 모멘트를 구하였고, 이것을 유한 요소 모델에 적용하여 각 치아의 변위와 응력 분포를 측정하였다. 브라켓에 발생하는 반력은 근원심 방향과 협설 방향으로의 힘은 0에 가까우며, 중절치, 측절치, 견치의 브라켓 근심측에서는 정출력이 원심측에서는 압하력이 발생하였다. 힘과 모멘트의 크기는 측절치에서 최대였고, 중절치, 견치 순으로 감소하였고, 소구치 부위와 대구치 부위에서는 급격히 감소하였다. 중절치와 측절치는 치관 협측, 원심 경사 이동과 압하를 보였으며, 견치는 치관 설측 원심 경사와 정출을 보였고, 제1소구치는 치관 설측 경사이동을 보였다. .019×.025 SS을 사용하여 상악 절치부에 토크를 부여하는 경우에는 측절치에 과도한 힘이 집중되므로, 임상에서 토크를 조절할 경우에는 NiTi나 TMA 호선을 사용하는 것이 바람직하리라고 생각된다. The purpose of this study was to investifate the stress distribtion in the periodontal tissue and the displacement of teeth when active torque was applied to the maxillary incisors by three-dimen-sional finite element analysis. A three- dimensional finite element model consisted of the maxillary teeth and surrounding periodontal membrane, .022×.028 Roth prescription bracket and stainless steel. NiTi and TMA rectangular ideal arch wires which were modeled by hexahedron elements. Applied active torques were 2, 5 and 10 degrees. The findings of this study showed that the reaction force acting on the bracket was the extrusion force on the mesial side of the incisors and canine and the intrusion force on the distal side of the incisors and canine.The amount of force and moment was greatest at the lateral incisor. When active anterior labial crown torque was applied, labial crown and distal tipping and intrusion of the incisors took place, and lingual crown distal tipping and extrusion of the canin occured. An excessive force was concentrated on the lateral incisor, when the stainless steel wire was used. NiTi or TMA wire os desirable for torque control.

Rat의 DNA Polymerase β cDNA가 도입된 Transgenic Drosophila의 체세포 돌연변이 유발에 관한 연구

최영현,유미애,이원호 부산대학교 유전공학연구소 1995 분자생물학 연구보 Vol.11 No.-

The effects of DNA polymerase β on the somatic chromosome mutations and mitotic recombinations were investigated using the transgenic Drosophila bearing chimeric gene consisting of a promoter region of Drosophila actin 5C gene and rat DNA polymerase β. For detecting the somatic chromosome mutations and mitotic recombinations, the heterozygous (mwh/+) strains possessing or lacking transgene pel β were used. The spontaneous frequency of small mwh spots, due deletion or nondisjunction etc, in the non-transgenic w strain and the transgenic p[pol β]-130 strain was 0.351 and 0.606, respectively. The spontaneous frequency (0.063) of large mwh spots, arises mostly from somatic recombination between the centromere and the locus mwh, in the transgenic p[pol β]-130 strain was about three times higher than that (0.021) of the non-transgenic w strain. The mutant clone frequencies of small and large mwh spots induced by N-methyl-N'-nitro-N-nitrosoguanidine and ethyl methanesulfonate in the transformant p[pol β]-130 were higher than those in the host strain w. The present results suggest that rat DNA polymerase β participate at least in the somatic chromosome mutations and mitotic recombination processes.