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.

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>

백서에서 치아이동 후 보정기간 동안 교합이 치주조직섬유의 재형성에 미치는 영향

정권희,박영준,이기헌,황현식 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.2

본 연구는 실험적 치아이동 후 보정기간 동안 교합이 치주조직섬유의 물리적 강도에 미치는 영향을 알아보고자 시행되었다. 체중 200g 내외의 Sprague-Dawley계 백서 수컷에서 상악 양측 제1대구치와 2대구치 사이에 교정용 고무줄을 삽입하여 4일 동안 치아를 이동시킨 다음, 각 실험동물의 하악 좌측 베1, 2, 3대구치를 발치하여 우측은 대합치가 있는 교합측으로, 좌측은 비교합측으로 구분하였다. 상악 제1대구치와 2대구치 사이의 인접면에 유지구를 형성하고 광중합형 레진으로 채워 보정을 시행한 후 시작 0일, 4일, 8일, 12일, 16일 또는 20일 경과한 후 백서를 희생시킨 다음, 만능물성 시험기를 이용하여 상악 제1대구치를 발치할 때 필요한 최대인장강도를 측정 좌우간 비교 분석하여 다음과 같은 결과를 얻었다. 1. 교합측은 비보정군에서 보정 4일, 8일, 12일, 16일, 20일군으로 갈수록 최대인장강도사 증가하였고, 보정 12일군 이후부터 통계적으로 유의한 차이를 보였다(p<0.05). 2. 비교합측은 비보정군에서 4일, 8일, 12일, 16일, 20일군으로 갈수록 최대인장강도가 증가하는 경향을 보였으나 통계적으로 유의한 차이를 보이지 않았다(p<0.05) 3. 교합측과 비교합측의 최대인장강도를 비교한 결과 보정 8일군까지 통계적으로 유의한 차이를 보이지 않았으나 (p>0.05), 보정 12일군 이후 보정 20일군까지 통계적으로 유의한 차이를 보였다(p<0.05). 이상의 결과는 실험적 치아이동 후 보정기간 동안 교합이 치주조직 섬유의 재형성에 영향을 미침으로 보정장치의 선택, 기간설정 등 보정계획서 교합에 대한 고려가 필요함을 시사하였다. The purpose of this study was to valuate the effect of occlusion on the mechanical strength of periodontal fibers during retention periods after experimental tooth movement. In the Sprague-Dawley male rats weighing 200g or more, the intraoral elastics were inserted into the both right and left interproximal space between upper first and second molars for tooth movement. After 4 days later, the left lower first, second, and third molars were extracted for differentiating the non-occlusal side from the occlusal side in the same mouth. At the same time the elastics were removes and than light cured resin was placed in the space between upper first and second molard following undercut was made for retention bilaterally. From the beginning of retention, 7 rats were sacrificed at 0, 4, 8, 12, 16, 20 days respectively. For evaluating of magnitude on the mechanical strength of periodontal tissue, the maximal shear load of the upper first molars were measured bilaterally during extraction using Instron Universal Testing Machine. The results of this study were obtained as follows : 1. In the occlusal side, the maximal shear load was increased from no retention to retention 20 days group as time was going and statistically difference was shown from retention 12 days group (p<0.05). 2. In the non-occlusal side, the maximal shear load was increased slightly from no retention 20 days group as time was going but there was no statistically difference (p>0.05) 3. The result compared with the maximal shear load between occlusal and nonocclusal side showed no statistically difference until retention 8 day group (p>0.05), but showed statistically difference from retention 12 day to 20 day group (p<0.05). These results show that occlusion had an effect on mechanical strength of the periodontal fibers during retention periods after experimental tooth movement; therefore, it is suggested that occlusion should be considered while the retainer types and retention period are planned.

백서에서 치아이동 후 보정기간 동안 교합이 치주조직 섬유의 재형성에 미치는 영향

정권희,이기헌,황현식,이석형 전남대학교 치의학연구소 2002 구강과학 Vol.14 No.2

The purpose of this study was to evaluate the effect of occlusion on the mechanical strength of periodontal fibers during retention periods after experimental tooth movement. In the Sprague-Dawley male rats weighing 200 g or more. The intraoral elastics was inserted into the interproximal space of upper the first and second molars. After 4th day of teeth movement, the left mandibular first, second, and third molars were extracted for differentiating the occlusal side from the non-occlusal side in the experimental groups. The intraoral elastics was removed and then light cured resin was placed in the interproximal space between the bilateral upper first and second molars following undercut was made for retention. From the day beginning retention, 7 rats were sacrified at 0, 4, 8, 12, 16, 20 days respectively. For evaluating of degree on the mechanical strength of periodontal tissue, maximal shear load of the bilateral upper first molars were measured by use of Instron Universal Testing Machine. The results of this study were obtained as follows: 1. In the occlusal side from no retention group to 4-day, 8-day, 12-day, 16-day, and retention 20-day group as time was going maximal shear load was increased and there was statistically difference from retention 12-day group(p<0.05). 2. In the non-occlusal side from no retention group to 4-day, 8-day, 12-day, 16-day, and retention 20-day group as time was going maximal shear load was increased slightly but there was no statistically difference(p>0.05). 3. The result compared with maximal shear load between occlusal and non-occlusal side showed no statistically difference until retention 8-daygroup(p>0.05), and showed statistically difference from retention 12-day to 20-day group(p<0.05). These results show that the occlusion had an effect on mechanical strength of the periodontal fibers during retention periods after experimental tooth movement; therefore, it is suggested that consideration of occlusion is required for the type and length of retention at the time of retention planning.

소화불량을 호소하는 만성위염 환자에서 Guaiazulene과 Dimethicone 복합제제 투여의 임상적 효과

이기천,정현용,이헌영,김영건 최신의학사 1993 最新醫學 Vol.36 No.9

素問·骨空論에 對한 硏究

曺基烈,鄭憲瑩,琴坰樹,朴炅 대한한의진단학회 1998 大韓韓醫診斷學會誌 Vol.2 No.2

The text of the Go1 Gong Ron (骨空論) of the So Moon (素問) was written in the Kap UI Kyung (甲乙經) volume 2 chapter 2 and volume 8 chapter 1. Also it was written in the Tae So (太素) volume 10, 11 and 26. In the Shin Kyo Jung (新校正), they say that it is wriien in the Jeon Won Ki Bon (全元起本) volume 2 and 6. But Wang (王永) interpreted it in volume 16. Also it was introduced in the Ryu Kyung (類經) volume 8, 9, 21 and 22 by Jang Kae Pin (張介賓) in the Myung (明) dynasty. In Go1 Gong (骨空), Gol(骨) means bone and Gong(空) means hole. So Go1 Gong(骨空) means the holes on bone of the human body. A large number of acupuncture points in 12 meridians are located on the holes of bone, and they are playing an important part in the treatment of diseases. In Go1 Gong Ron (骨空論), many points that is choosed when we treat various diseases by acupuncture are mentioned, locations that the holes of bone are distributed in are introduced. So it is called Go1 Gong Ron (骨空論) . This article of the research on the Go1 Gong Ron (骨空論) can be divided into 4 chapters. Summerking the contents of the Go1 Gong Ron (骨空論) in reference to the contents of successive generation note, the contents were as follows. Chapter 1 is about the way to use in treating various diseases what caused by Pung Sa (風??) and deals with the methods of locating acupoints based on a frame. Chapter 2 is written about lines that Conception Vessel (任??), Governer Vessel (????), and Throughfare Vessel (????) pass through, and pathological explanations on the diseases which are belong to those three meridians. The name of each part of the leg and the treatment corresponded to each phase of diseases of the leg are also mentioned in this chapter. Chapter 3 is concretely written about the name and position of the hole on bone of the human body. Chapter 4 deals with moxibustion therapy which we use to treat having an attack of indigestion, being bitten by dog, and feeling cold and heat in turn. Because the ancient men used acupuncture as main treatment of disease, they thought much of acupoint. A large number of acupoints are located on the holes of bone, and are playing an important part in the treatment of diseases. Therefore well understanding of Gol Gong Ron (骨空論) is very important. It is too difficult to understand the Gol Gong Ron (骨空論), because it is written in old Chinese. Consequence of above reason, the writer of this article has researched to find out the exact meaning of that.

안면비대칭 진단을 위한 하악골 3차원영상 계측기준치에 관한 연구

안정순,이기헌,황현식 대한치과교정학회 2005 대한치과교정학회지 Vol.35 No.2

기존의 2차원적 진단자료는 상의 확대 및 왜곡으로 인해 형태나 크기의 정량적 평가시부적절한 결과를 야기할 수 있어 안면비대칭의 정확한 진단과 치료계획 수립을 위해서는 3차원영상 진단의 도입이 필요하다. 본 연구는 안면비대칭 진단시 3차원적 분석에 도움이 되는 기준자료를 얻고자 정상교합자를 대상으로 하악골 3차원영상 계측항목의 평균값과 좌우차이의 정상범주를 알아보기 위하여 시행되었다. 뚜렷한 안면비대칭을 보이지 않는 성인 정상교합자 남녀 30명씩 총60명을 대상으로 두경부 전단화단층사진을 촬영한 후 컴퓨터 프로그램을 이용한 각각의 단면 촬영영상 정보를 이용하여 3차원 입체영상을 재구성한 다음, 하약골 비대칭시 좌우차이를 보일 수있는 계층항목 ramus length를 나타내는 6개 condyla neck length를 나타내는 1개, mandibular body length를 나타내는 8개 등 15개의 거리 계층항목과 gonial angle을 나타내는 4개, frontal ramal inclination을 나타내는 2개, lateral ramal inclination을 나타내는 2개 등 8개의 각도계층항목. 총 23개의 계층항목을 설정한 후, 좌측과 우측을 구분하여 컴퓨터 상에서 3차원계측치를 구하고 좌우차이값을 산출하였다. 본 연구결과 얻어진 정상교합자의 하악골 3차원영상 계층항목의 좌우차이값은 안면비대칭 환자의 진단 기준치로 유용하게 사용될 수 있을 것이다. For an accurate dlagnosis and treatment planning of facial asymmetry, the use of 3-dimensional(3-D) image is indispensable. The purpose of this study was to get standard data for the 3-D analysis of facial asymmetry.Computerized tomography(CT) was taken in the 60 normal occlusion individuals (30 male, 30 female) who did not have any apparent facial asymmetry. The acquired 2D CT DICOM data were input on a computer, and the reformatted 3-D images were created using a 3-Dimage software. Twenty three measurements were established in order to evaluate asymmetry:15linear measurements (6 for ramus length, 1 for condylar neck length, and 8 for mandibular body length) and 8 angular measurements (4 for gonial angle, 2 for frontal ramal inclination, and 2 for lateral ramal inclination). The right and left difference of each measurement was calculated and analyzed. Itis suggested that the right and left differences of the measurements obtained from the study could be used as references for the diagnosis of facial asymmetric patients.

식도정맥류출혈에 대한 내시경적 경화요법의 시술방법에 따른 지혈효과의 비교연구

이헌영,이기천,정현용,김영건 충남대학교 의과대학 지역사회의학연구소 1991 충남의대잡지 Vol.18 No.2

Endoscopic Injection Sclerotherapy(EIS) is currently the primary treatment of choice for the majority of patients who present esophageal vsarix bleeding. But, in EIS, unanswered methodologic problem and controversies remain. We assigned 99 patients with esophageal varix bleeding seen at Chungnam National University Hospital from May. 1989 to Dec. 1991. Single injection at one varix column was made in 73 patients (Mono-puncture group) and multiple injections were made in 26 patients (Multi-punctures group). The results are follows 1) Mean age was 48.01±11.4 years and male to female ratio was 7:1, but there was no difference between 2 groups. 2) Most frequent etiology of bleeding varices were alcoholic liver cirrhosis(43 %) and hepatitis B virus associated liver cirrhosis(31%), and the most patients had a advanced liver disease, such as Child's classification B(46%) and C(29%), but there was no difference between 2 groups. 3) In variceal form, rates of Fl, F2 & F3 were 2%, 27%, & 67%, and red color sign was seen in 80% of patients, but there was no difference between 2 groups. 4) Total number of treatment were 3.1± 2.1 in mono-puncture group and 4.1± 3.0 in multi-puncture group, and total volumes of sclerosant were 21.3± 17.Oml, 30.3± 19.4m1. Mean volumes per treatment session was 6.9± 4.5ml, 7.4± 5.9ml, and mean volume per one puncture site were 1.6± 1.0 ml and 1.1± 0.9ml. There were significantly difference between 2 groups in total volume of sclerosant and mean volume per one puncture site. 5) Before and after EIS, the changes of hematologic finding were not significant, and transfusion requirments were decreased, in both groups. 6) Complications of EIS were chest and epigastric pain(82%), fever(31%), pleural effusion(8%), sclerotherapy failure(9%) and rebleeding during admission(15%), but there was no difference between 2 groups. These findings suggest that differences of clinical effects and complications were not significant between 2 groups.

전기도금을 이용한 스테인레스 스틸 각형 선재의 굵기 증가 후 물성 변화

이정석,이기헌,황현식 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.2

본 연구는 전기도금을 이용하여 각형 선재의 굵기를 증가시킨 후 기존의 선재와 물성을 비교함으로서 이의 임상적 적용 가능성을 알아보고자 시행되었다. 한 변의 길이가 0.016 인치인 정사각형 스테인레스 스틸 교정용 선재에 니켈 전기도금을 시행하여 굵기를 0.01 인치 증가시켜 한 변의 길이가 0.017 인치인 정사각형 선재로 만들었고 도금층의 밀착성을 증진시키기 위해 400℃의 전기로 에서 10분간 열처리를 시행하였다. 시편의 물성변화를 알아보기 위하여 전기도금을 이용하여 제작된 15개의 시편을 실험군(016P군)으로, 기존의 0.016인치(016), 0.017 인치(017군) 스테인레스 스틸 교정용 선재를 대조군으로 설정한 후 3점 굴곡 시험과 비틀림 시험을 시행하여 다음과 같은 결과를 얻었다. 1. 3점 굴곡 시험 결과 016P군에 비해 강성과 항복강도, 국한강도 모두 증가하는 경향을 보였으며, 강성과 극한강도는 통계적으로 유의한 차이가 있었다(p<0.05). 2. 3점 굴곡 시험 결과016P군이 017보다 강성과 항복강도, 극한강도 모두 낮은 경향을 보였으며, 강성은 통계적으로 유의한 차이가 있었다(p<0.05). 3. 비틀림 시험 결과 016P군이 016군에 비해 비틀림 모멘트, 최대 비틀림 모멘트 모두 높았으며, 통계적으로 유의한 차이가 있었다(p<0.05). 4. 비틀림 시험 결과 016P군이 017군에 비해 비틀림 강성과 항복 비틀림 모멘트, 최대 비틀림 모멘트 모두 낮은 경향을 보였으며, 이 중 항복 비틀림 모멘트와 최대 비틀림 모멘트에서 통계적으로 유의한 차이가 있었다(p<0.05). 이상의 결과를 요약해 보면 각형 선재에 도금을 시행하여 굵기를 증가시키고 물성이 증가될 수 있음을 알았다. 비록 도금을 시행한 016P군이 기존의 017군보다 강성이 낮았으나 이는 반대로 016P군이 017군보다 탄성이 높음을 나타내며 토크조절이 부족한 경우 브라켓 슬롯에 쉽게 삽입되어 교정력을 발휘할 것으로 기대된다. The purpose of this study was to evaluate clinical applications of electroplating method through investigation of the physical properties of orthodontic rectangular wires according to varying their cross section. For the study, it was accomplished to electroplate the 0.016-inched orthodontic rectangular stainless steel wire. The cross section of stainless steel orthodontic rectangular wire increased from 0.016 x 0.016 inch to 0.017 x 0.017 inch by electroplating. The wire was heat treated to improve an adhesion between the wire and electroplated metal. A three=point bending test and torsion test were conducted in order to compare physical properties among three wire groups; 0.016 X 0.016 wires (group 016), electroplated 0.016 x 0.016 wires (group 016P) and 0.017 x 0.017 wires (group 017). Through the investigation of each wire group, following results were obtained. 1. At three-point bending test, the group 016P showed higher tendency in the degree of stiffness, yield strength and ultimate tensile strength than the group 016. Stiffness and ultimate tensile strength showed statistically significant differences between two groups at three-point bending test (p<0.05). 2. Stiffness, yield strength, and ultimate tensile strength of the group 016P showed lower tendency than those of the group 017. Stiffness showed statistically significant differenced between two groups at three-point bending test (p<0.05). 3. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed higher tendency than those of the group 016. All measurements showed statistically significant differences between two groups after torsion test (p<0.05). 4. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed lower tendency than those of the group 017. Yield torsional moment, and ultimate torsional moment showed statistically significant differences between two groups after torsion test(p<0.05)

김천대학 사회교육 활성화 방안에 관한 연구

고정환 ; 윤옥현 ; 박홍기 ; 전기환 ; 김상민 ; 김학민 ; 박희룡 김천대학교 1999 김천대학교 논문집 Vol.20 No.-

The social education that is provided for the people will be an important part of the national growth in the 21 century. This study was taken to present the desirable direction that Kimcheon College Continuing Education has to make progress as a central organization with perceiving the importance of continuing education for the Kimcheon citizen. To achieve the objective of the study, examined a sample of 592 citizen and students from Kimcheon City and Kimcheon College. The survey revealed the following results : 1. Offer the effective operation of education policies and curriculums. 2. Perform the role of foreign language education center. 3. Introduce the saving credit system. 4. Operate the special lectures for the students of the high school graduating class after the national scholastic achievement test for university and college entrance. 5. Suppert the special skills education for high school students after-school hours. 6. Administer the new employment program. These results showed the desirable direction that the Kimcheon College Continuing Education has to take some actions for the Kimcheon citizen.