촉매를 이용한 이산화탄소 고정화 및 고리형 카보네이트 합성반응에 대한 계산화학적 해석

안혜영(Hye Young An),김민경(Min-Kyung Kim),정희철(Hui Cheol Jeong),엄기헌(Ki Heon Eom),원용선(Yong Sun Won) 한국청정기술학회 2016 청정기술 Vol.22 No.1

본 연구에서는 이론화학 또는 분자모델링이라 불리는 계산화학을 기존에 연구된 촉매반응 실험결과를 해석하는 데 접목시켜 보았다. 온실효과의 주범인 이산화탄소를 에폭사이드와 반응을 통해 고정화하고 카보네이트를 생성하는 반응을 선택하였는데 이 반응은 활성화 에너지(55~59 kcal/mol)가 높아 촉매의 사용이 불가피하다. 많은 기존 연구들 중에 ZIF-90/ionic liquid immobilized ZIF-90 (IL-ZIF-90), polystyrene-supported quaternized ammonium salt, KI/KI-glycine, dimethylethanolamine (DMEA)를 촉매로 사용한 경우에 대해 반응의 각 단계를 계산하여 반응의 경로를 예측하고 단계별로 구한 에너지를 바탕으로 에너지도를 구성함으로써 실험결과를 열역학적으로 해석하였다. ZIF-90/IL-ZIF-90과 KI/KI-glycine의 경우는 실험적으로 후자들이 상대적으로 높은 수율을 얻었는데 계산 결과 활성화에너지가 낮아진 이유가 아니라 전자들의 경우 반응 중간체가 높은 에너지를 가져 반응물로 되돌아가는 역반응에 의해 정반응의 진행이 방해를 받은 것으로 밝혀졌다. DMEA를 촉매로 사용하였을 경우는 활성화 에너지를 ~42 kcal/mol로 낮춰줌으로써 금속이나 할로겐염 없이도 촉매의 활성이 잘 일어남을 증명하였다. 폴리스티렌(polystyrene)으로 지지된 quaternized 암모늄염 촉매의 경우 클러스터 가정을 사용하여 계산을 진행하였으며 암모늄염의 -NH기와 에폭사이드의 O 원자 사이의 상호작용의 가능성을 확인할 수 있는 반응경로를 제시하였다. In this study, a computational chemistry methodology called as molecular modeling was been applied to explain several experiment results mechanistically. The reaction chosen for this study was to remove carbon dioxide, known as a primary greenhouse gas, by an epoxide via the carbon dioxide fixation to produce carbonates. This reaction inherently needs the use of catalysts because it has a significantly high activation barrier (55~59 kcal/mol). Among various types of catalysts, we studied in zeolitic imidazolate framework 90 (ZIF-90)/ionic liquid immobilized ZIF-90 (IL-ZIF-90), polystyrene-supported quaternized ammonium salt, KI/KI-glycine, and dimethylethanolamine (DMEA). First, probable reaction pathways were proposed based on calculated energetics by computational chemistry. The energetics was then used for the thermodynamic interpretation on the activity of catalysts. In the case of ZIF-90/IL-ZIF-90 and KI/KI-glycine, IL-ZIF-90 and KI-glycine showed better yields compared to their counterparts. The calculation proposed interesting results that it is not from the lowering of activation energy but from the unstable intermediates of ZIF-90 and KI-glycine. For DMEA, the calculated activation energy was ~42 kcal/mol, much lower than that of the non-catalytic reaction. A possible reaction pathway was located to confirm the interaction between -NH group from ammonium and oxygen from epoxide for polystyrene-supported quaternized ammonium salt.

방사선조사와 Paclitaxel의 병합요법에 의한 신내막 과증식억제

장기육,승기배,강동헌,임상현,정해억,임효영,김태균,김연실,채장성,김재형,홍순조,윤세철,최규보 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.6

The fate of spinal schwannomas following subtotal resection: a retrospective multicenter study by the Korea spinal oncology research group.

Sohn, Seil,Chung, Chun Kee,Park, Sung-Hye,Kim, Eun-Sang,Kim, Ki-Jeong,Kim, Chi Heon M. Nijhoff ; Kluwer Academic Publishers 2013 Journal of neuro-oncology Vol.114 No.3

<P>The fate of residual spinal schwannomas needs to be estimated in order to plan further management after subtotal removal. Our aim was to evaluate the growth rate of residual spinal schwannomas and compare results in regrowth and no regrowth groups by using data collected from the Korea Spinal Oncology Research Group database. From January 1989 to August 2011, 27 patients with residual spinal schwannomas were selected. Patients with at least two follow-up magnetic resonance image (MRI) studies after subtotal resection were included. The mean period of MRI follow-up was 62.4 months. A tumor size increase of over 2 mm in the maximal diameter was considered indicative of regrowth. Age, sex, size at initial diagnosis, postoperative tumor size, and Ki-67 labeling index were compared between regrowth and no regrowth groups. Eight residual schwannomas regrew (29.6 %), and 19 (70.4 %) did not regrow. Average growth rate of the regrowing tumors was 1.0 4.4 mm/year. The mean percentage increase in tumor size during follow-up was 10.0 28.8 %. The Ki-67 labeling indices were significantly different between regrowth and no regrowth groups (P = 0.014). Two patients underwent a revision operation for significant tumor regrowth. Nineteen cases (70.4 %) among 27 residual spinal schwannomas did not regrow significantly, but further surgical treatments were necessary in 2 patients due to significant regrowth. The Ki-67 labeling index was higher in the regrowth group. Earlier follow-up MRI is recommended for patients whose tumors have higher Ki-67.</P>

自由놀이 活動에 관한 硏究

金基玄 又石大學校 1983 論文集 Vol.5 No.-

This study was aimed to find out the daily lesson period and located time for the free play activities, teacher's recognitions of values for the free play activities, teacher's role in various situations during the activities, and problem for the teacher's guidance for the activities, to get necessary information for the effective guidance for the free play activities. Questionnaire paper asked to the 80 teachers from 80 kindergartens in Jean Bug region, the recovery ratio of Questionnaires was 85%. Findings of the research are as follows : 1. In general 40-60 minutes a day are alocated for the free play activities, regardless to daily lesson period, and alocated time changes according to the seasons. 2. The teachers have revealed some tendency of putting first priority on the physical values of the free play activities, next on social values, on intellectual values. 3. The teachers pay attentions to trouble among infants during the activities to suggest for their solutions, but in other play parts they seldom pay any attentioks ons. 4. Imaginary play materials, creative play materials, rhythms materials, and printed materials are moderately provided. However natural play materials, science play materials are poorly ed. provid- 5. It is the Problems for the teacher's guidance for the free play activities that play materials are poorly provided, the teachers are not sufficient in number, space and time either.

勞使關係와 勞動行政에 관한 硏究

金憲起 대구보건대학 1991 대구보건대학 論文集 Vol.12 No.-

The purpose of the Labor-Management Council System is to rise the productivity through the communication between the union and management, to promote the welfare of the laborer and to stabilize the Labor-Management Relations. But the present Labor-Management Council System has been successfully operating. Though the rise of the productivity, the target level of the manager and manage organization, has been achieved, the promotion of the welfare of the laborer and the stabilization of the Labor Management relations have not been achieved. In particular, the grievance handling which is closely connected with the promotion of the welfare and the stabilization of the Labor-management relations has not been ineffective due to the enervated grievance handling committee. partly because the antagonistic relations between employer and employee has been restricted conceiving the Labor-Management Council System in Korea, partly because the Collective Bargaining of the Union has been curbed partly because the conciliatory side in the Labor-Management Council System has been emphasized. To develop the Labor-Management Council System normally, not only the laborer, the Labor-Management Council, the enterprise and the Government should improve the Labor Management Council System systematically and administratively, but also, labor collective bargaining right being allowed, the Union and the Labor-Management Council System should be developed equally to induce re the mutual co-operative relation. In addition, to form the basis of it, the consciousness level of the Labor-Management relation and the managerial environment should be made better as well as the desirable Labor-Management and Administration must be taken a triangular position. In conclusion, I would like to present the following suggestions as to the directions in developing the Labor-Management Council System and achieving the prosperity of the Labor and Management. 1. The Labor-Management Council System should be improved systematically as well as the Union and the Labor-Management Council System should be developed equally to induce to the mutual co-operative relation. 2. It is quite necessary to recognize that the Labor-Management relation is neither only antagonistic nor only co-operative. For the relation should be compatible and commensal. 3. In the managerial and administrative environment, the humanism should be expanded to harmonize the efficiency and the humanism. 4. It is quite important that the unequal bargaining power should be recovered by the sublation of the exceeding governmental interference in the triple relations of the Labor, Management and Administration so that the equal dynamic relations might be realized. 5. The Labor-Management Administration should pursuit the democratic welfare administration which is the harmony of the laissez-faire administration 2nd the control administration and to do it, in the Labor-Management, Administration, the specialization, the individuality and the democracy should be guaranteed.

AR기법을 이용한 SLAM 영상 개선

김현,송대건,황기환,연규헌,전계석 慶熙大學校 大學院 1998 高凰論集 Vol.22 No.-

In this paper, we have been studied the enhancement of SLAM image using average response methos. AR methos has been used to reduce the random noise in signal processing. In this the experiment, we have constructed the SLAM system of 10㎒ operating frequency and experienced for holed Al sample. In this experimental result, we have been found that SLAM using AR method was able to get the high-speed and enhanced image compared with SAM.

전산화단층사진을 이용한 하악골 3차원 영상에서 비대칭진단 계측항목의 재현도에 관한 연구

김고운,김재형,이기헌,황현식 대한치과교정학회 2008 대한치과교정학회지 Vol.38 No.5

본 연구는 하악골 3차원 입체영상에서 비대칭계측항목들의 재현도 비교를 통하여 안면비대칭 진단 시 유용한 계측점 설정에 도움이 되고자 시행되었다. 40명의 두경부 전산화단층사진을 이용하여 생성한 3차원 영상에서 하악골 형태를 결정짓는 부위로 하악과두, 하악우각부, 하악정중부를 선택하고 각 부위의 세부위치에 따라, 그리고 측정 시 보는 각도에 따라 구분하여 하악과두의 경우 Cd_(sup_sup) 등 6개, 하악우각부의 경우 Go_(inf_lat) 등 10개, 하악정중부의 경우 Me_(ant), Me_(inf) 등 총 18개의 계측점을 설정한 후 이를 이용하여 하악골 비대칭 시 좌우 차이를 보일 수 있는 25개의 계측항목을 설정 및 계측한 후 조사자간 및 조사자내의 재현도를 비교 평가하였다. 조사자간 재현도의 경우 25개의 계측항목 중 3개를 제외한 모든 계측항목에서, 조사자내 재현도의 경우 2개 항목을 제외한 모든 계측항목에서 높은 재현도를 보였다. 아울러 본 연구에서 설정한 18개의 계측점 중 Go_(mid_lat), Go_(mid_obl)가 포함된 계측항목이 조사자간 및 조사자내 재현도가 떨어지는 경향을 보였다. 이상의 연구 결과 본 연구에서 사용된 18개의 계측점 중 16개의 계측점(과두를 나타내는 Cd_(sup_sup), Cd_(lat_ant), Cd_(lat_lat), Cd_(post_lat), Cd_(post_post), S, 하악우각부를 나타내는 Go_(inf_lat), Go_(inf_inf), Go_(lat_ant),Go_(lat_lat), Go_(post_lat), Go_(post_post), Ag_(lat), Ag_(inf), 하악정중부를 나타내는 Me_(ant), Me_(inf))은 높은 재현도를 보이므로 전산화단층사진을 이용한 하악골 3차원 영상에서 안면비대칭 환자의 진단에 유용하게 사용될 수 있음을 시사하였다. Objective: The purpose of this study was to evaluate the reproducibility of measurements representing asymmetry of the mandible and to identify which landmarks would be more useful in 3-dimensional (3D) CT imaging. Methods: Facial CT images were obtained from forty normal occlusion individuals. Eighteen landmarks were established from the condyle, gonion, and menton areas, and 25 measurements were constructed to represent asymmetry of the mandible; 8 for ramus length, 12 for mandibular body length, 1 for condylar neck length, 2 for frontal ramal inclination, and 2 for lateral ramal inclination. Inter- and intra-examiner reproducibility of the measurements was evaluated. Results: Inter-examiner reproducibility of the measurements proved to be high except for 3 measurements. Intra-examiner reproducibility also proved to be high except for 2 measurements. Interand intra-examiner reproducibility of the measurements including Gonion proved to be low. Conclusions: The results of the present study indicate that the landmarks and measurements constructed in 3D CT images can be used for the diagnosis of facial asymmetry.

치과진료에 전기침자극요법의 응용

김기석,송윤헌 대한두개하악장애학회 1995 대한두개하악장애학회지 Vol.7 No.1

간세포암과 감별이 어려웠던 악성중피종 치험 1예

김선문,허원석,채경훈,강윤세,정재훈,김연수,박기오,문희석,이엄석,김석현,성재규,이병석,이헌영,신경숙,조준식,송인상,강대영 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

Malignant peritoneal mesothelioma is a rare neoplasm that arises from the mesothelium of a serosal cavity and is a rapidly fatal disease with a median survival of 4 to 12 months for untreated cases. Recently, we experienced a case with malignant peritoneal mesothelioma who was suspected hepatocelluar carcioma by abdominal CT scan and was confirmed by biopsy including immunohistochemical stain(calretinin) after surgery. We performed tumor excisions and wedge resection of the liver(segment Ⅷ)and inserted Tencoff catheter in abdominal cavity at 25th day of post-operation. We treated with intraperitoneal paclitaxel(25mg/m^(2)/day for 5 days) six courses monthly. She was well tolerable and is still living without any evidence of recurrence for 14th month of post-operation.

교정용 선재의 직경 증가를 위한 전기도금법과 무전해도금법의 비교연구

김재남,이기헌,황현식,성영은 전남대학교 치의학연구소 2002 구강과학 Vol.14 No.3

The purpose of this study was to evaluate electroless plating as a method to increase diameter of an orthodontic wire through comparison with eletroplating. After pretreatment for plating to the stainless steel orthodontic wire of 0.016 inch. the electoless plating was done under the condition of 90'c until the diameter of the wire was increased to 0.018 inch using Hessonic-Gr® which was sold by Shin-Pung metal. On the process of electroless plating the diameter of wire was measured every 5 minute to examine the increasing ratio of the wire's diameter per time unit. And to examine the uniformity, the diameter of each 3 points of the electroless-plated orthodontic wire was measured. An X-ray diffraction test was performed to analyze the nature of the plated metal and physical property test was made. Through the comparison with electroplating, following results were obtained. 1. In stiffness. yield strength, and ultimate strength of electroless plating wire group showed higher tendency than those of electroplated wire group, and in stiffness and ultimate strength there was statistically significant difference between two groups. 2. In the electroless plating wire group. the increasing ratio of the diameter was 0.O0461±0.00003 mm/5min (0.O0092 mm/min). In the electroplated wire group, that was 0.O0821±0.O0015 mm/min. 3. The results of uniformity test to measure the diameter of each 3 points showed a tendency of uniformity in all the two plating method. The results of this study suggest that the electroless plating wire is more close to the ready-made wire than electroplating wire in terams of the physical property. On the other hand. the length of plating time should be solved for the clinical application of electroless plating.