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>

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

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.

내시경으로 진단된 소화성 궤양의 임상적 고찰

김영건,육은주,김성걸,임의혁,성자원,김병호,허승식,이기천,정현용,이헌영 충남대학교 의과대학 지역사회의학연구소 1993 충남의대잡지 Vol.20 No.2

A clinical analysis was performed of 3055 pateints with peptic ulcer who were diagnosed with gastroduodenoscopy, in Hospital of Chungnam National University College of Medicine from July 1988 to May 1993. 1) During the period 1988-1993, The proportion of gastric ulcer among peptic ulcer decreased from 47.8% to 42.8%, but that of duodenal ulcer increased from 36.8% to 39.6%. 2) Of the 3055 cases, the number of patients with esophageal ulcer was 98(3.2%), with gastric ulcer 1407(41.6%), with. duodenal ulcer 1104(36.1%), with channel ulcer 149(4.9%), and with combind ulcer 297(9.7%). 3) We observed a peak incidence of peptic ulcer in the 50-69age group, gastric ulcer in the 5069age, duodenal ulcer in the 40-59age group. The ratio of male to female was 3.6 : 1 in peptic ulcer, 4.4 : 1 in gastric ulcer, 3.0 : 1 in duodenal ulcer. 4) The common site was angle in gastric ulcer, and bulb in duodenal ulcer. 5) The active stage was 39.4% of gastric ulcer, and 37.4% of duodenal ulcer, the healing stage was 34.2% of gastric ulcer, and 17.9% of duodenal ulcer, and the scar stage of gastric ulcer was 26.4%, and duodenal ulcer was 44.7%. 6) The size of ulcer was less than 1Cm in 66.7% of gastric ulcer, and in 75.5% of duodenal ulcer, the size of ulcer was greater than 2Cm in 13.2% of gastric ulcer, and in 6.5% of duodenal ulcer. 7) The frequency of multiple ulcer was 29.9% in gastric ulcer, and 16.5% in duodenal ulcer.

Chloral hydrate/Hydroxyzine과 Midazolam/Meperidine의 경우 투여 진정효과에 관한 비교 연구

김용헌,김지연,박기태 大韓小兒齒科學會 2005 大韓小兒齒科學會誌 Vol.32 No.2

본 연구의 목적은 소아 환자의 치과 진료를 위한 진정요법 시 chloral hydrate와 hydroxyzine의 경구 투여와 midazolam과 meperidine의 경구 투여간의 임상적인 진정효과 및 합병증 발생 여부를 비교하는 것이다. 삼성서울병원 소아치과를 내원한 환아 중 ASA I또는 Ⅱ에 해당하는4세 미만의 아동 15명을 대상으로 하여 한 달여 간격으로 두 차례에 걸친 진정요법을 시행하였다. 2회의 진정요법 중 1회는 chloral hydrate (60mg/kg)/hydroxyzine(25mg)을 경구 투여하고 나머지 1회는midazolam(1mg/kg)/meperidine(1mg/kg)을 경구 투여하였으며 투여 순서는 무작위로 정하였다. 두 차례 모두 N₂O-O₂, 흡입진정을 병용하였다. 각 치료과정에 따른 진정효과는 Houpt Scale(수면, 움직임, 울음, 전반적인 행동 지수)로 측정하였고 pulse oximeter를 이용하여 저산소증의 유무를 비교, 평가하고 약물 투여 후 구토의 여부를 함께 평가하여 다음과 같은 결과를 얻었다. Chloral hydrate와 hydroxyzine을 경구 투여한 군이 midazolam과 meperidine을 경구 투여한 군보다 전반적인 행동 지수에서 통계학적으로 유의하게 우수한 결과를 보였으며 어느 군에서도 저산소증은 보이지 않았다. 본 연구에서는 chloral hydrate와 hydroxyzine의 경구 투여가 midazolam과 meperidine의 경구 투여보다 우수한 진정효과를 보이는 것으로 판단된다. The purpose of this study was to compare the efficacy and complications of two oral sedative regimens, chloral hydrate(60mg/kg)/hydroxyzine(25mg) versus midazolam(1mg/kg)/meperidine(1mg/kg) for the sedation of pediatric dental patients. Fifteen patients(mean age 36.2months, range 24-47months), ASA Class I or II, who needed at least two restorative dental procedures were selected in this double-blind, randomized study. All subjects were randomly assigned to receive either chloral hydrate/hydroxyzine or midazolam/meperidine and 50% N₂O/0₂ was administered at each appointment. Behavior assessment(sleep, movement, crying, overall behavior) was made using Houpt Sedation Rating Scale and physiologic parameters(pulse rate, oxygen saturation) were monitored using pulse oximeter. The incidence of hypoxia(SpO2 90% or less, at least 10s duration) and vomiting was recorded. Patients sedated with chloral hydrate/hydroxyzine showed significantly better overall behavior score than patients sedated with midazolam/meperidine. There was no clinically significant difference in the incidence of hypoxia and vomiting. It was concluded that oral administration of chloral hydrate/hydroxyzine is more effective than midazolam/meperidine for the sedation of pediatric dental patients.

안면비대칭자의 3차원 전산단층사진 분석에서 경·연조직간 비대칭 정도 차이

김왕식,이기헌,황현식 대한치과교정학회 2005 대한치과교정학회지 Vol.35 No.3

본 연구는 안면비대칭 환자에서 경조직의 비대칭 정도와 연조직 비대칭 정도의 차이를 3차원적으로 밝히고자 시행되었다. 안면비대칭으로 보이는 성인 남녀 34명을 대상으로 두경부 전산단층사진을 촬영하고 3차원 입체영상으로 재구성한 후 기준평면에 대해 비대칭을 나타내는 6개의 계측항목을 경조직에 설정하고, 이에 대응하는 연조직계측항목을 각각 설정한 후 3차원 계측을 시행하고 경조직과 연조직의 계측항목간 차이를 비교하였다. 이부편위측과 반대측간의 계측치 차이를 비교한 결과, 경조직과 연조직 모두에서 좌우측 계측치관에 통계적으로 유의한 차이가 관찰되었으며 경조직과 연조직의 비대칭 계측항목을 비교한 결과. 0개의 계측항목 모두에서 통계적으로 유의한 차이를 나타내었다. 이부편위를 나타내는 chin deviation, 하악지와 하악골체를 나타내는 frontal ramal inclination difference. frontal corpus inclination difference 항목은 경조직의 비대칭 정도에 비하여 연조직 비대칭정도가 작게 나타난 반면, 입술경사를 나타내는 lip cheilion height difference. lip canting은 maxillary height difference, occlusal plane canting보다 크게 나타나 입술부위의 비대칭 정도는 하부 경조직의 비대칭정도보다 큰 것으로 나타났다. 안면비대칭자에서 경조직과 연조직간 비대칭 정도 차이를 규명한 본 연구 결과는안면비대칭 평가 시 경조직 외에 연조직 계측항목을 이용한 비대칭 분석도 필요함을 시사하였다. The purpose of this study was to compare the asymmetric degree between maxillofacial hard and soft tissues in individuals with facial asymmetry. Computerized tomographies (CT) of 34 adults (17 male, 17 female) who had facial asymmetry were taken. The CT images were transmitted to personal computers and then reconstructed into three-dimensional (3D) images through the use of computer software. In order to evaluate the degree of facial asymmetry, 6 measurements were constructed as the hard tissue measurements while 6 counterpart measurements were taken as the soft tissue measurements. The means and standard deviations were obtained for each measurement using 3D measure, then t-test was used to investigate the differences between each hard tissue measurement and the corresponding soft tissue measurement. All measurements used in the present study showed statistically significant differences between the hard and soft tissues. The degree of soft tissue asymmetry was smaller than that of corresponding hard tissue asymmetry in case of chin deviation, frontal ramal inclination difference, and frontal corpus inclination difference. On the other hand, the degree of soft tissue asymmetry was greater than that of underlying hard tissue asymmetry in the measurement of lip canting and lip cheilion height difference. The present study suggests that asymmetric differences of hard and soft tissue is observed in facial asymmetric subjects, and thus soft tissue analysis is needed in addition to hard tissue analysis when making an evaluation of facial asymmetry.

교정용 선재의 직경 증가를 위한 전기도금법과 무전해도금법의 비교연구

김재남,조진형,성영은,이기헌,황현식 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.2

본 연구는 교정용 선재의 직경을 증가시키기 위한 방법으로 무전해도금법의 이용 가능성 여부를 전기도금법과의 비교를 통해 알아보고자 시행되었다. 0.016 인치 스테인레스 스틸 교정용 선재에 도금을 위한 전처리를 시행한 후, 시중에 판매되는 무전해니켈도금액(Hessonic-Gr, 신풍금속, 한국)을 사용하여 90℃ 온도에서 0.018 인치 직경이 될 때까지 도금을 시행하였다. 무전해도금 과정 중 시간에 따른 직경증가율을 구하는 한편, 도금 후 세 지점의 직경을 계측하여 균일성을 평가하였다. 도금 금속의 정성분석을 위하여 X-선 회절분석을 시행하는 한편, 물성검사를 시행한 후 전기도금한 경우와 각각 비교 분석하였다. 연구결과 무전해도금한 군이 전기도금을 시행한 군보다 강성, 항복강도, 극한강도 모두 높은 경향을 보였으며 강성과 극한강도에서 통계적으로 유의한 차이를 나타내었다 (p < 0.05). 또한 무전해도금한 군의 직경증가율은 0.00461 ± 0.00003mm/5min (0.00092mm/min)로, 전기도금한 군의 직경증가율 0.00821 ± 0.00015mm/min와 차이를 보였다. 도금 후 세 지점의 직경을 계측하여 균일성을 평가한 결과, 두가지 도금법 모두에서 균일한 양상을 보였다. 이상의 결과로 무전해도금법을 통해 직경이 증가된 선재가 전기도금법에 의해 직경이 증가된 선재보다 기존의 선재와 가까운 물성을 보임을 알 수 있었으며, 이의 임상적 적용을 위해서는 도금시간의 감소가 필요함을 알 수 있었다. The purpose of this study was to evaluate electroless plating as a method of increasing the diameter of an orthodontic wire in comparison with eletroplating. After pretreatment plating of the 0.016 inch stainless steel orthodontic wire, electroless plating was performed at 90℃ until the diameter of the wire was increased to 0.018 inch. During the process of electroless plating, the diameter of the wire was measured every 5 minutes to examine the increasing ratio of the wire's diameter per time unit. And to examine the uniformity, the diameter at 3 points on the electroless-plated orthodontic wire was measured. An X-ray diffraction test for analyzing the nature of the plated metal and a 3-point bending test for analyzing the physical property were performed. The electroless-plated wire group showed a increased tendency for stiffness, yield strength, and ultimate strength than the electroplated wire group. And there was a statistically significant difference between the two groups for stiffness and ultimate strength. In the electroless-plated wire group, the increasing ratio of the diameter was 0.00461 ± 0.00003 mm/5 min (0.00092 mm/min). In the electroplated wire group, ti was 0.00821 ± 0.00015 mm/min. The results of the uniformity test showed a tendency for uniformity in both the plating methods. The results of this study suggest that electroless plating of the wire is closer to the ready-made wire than electroplating wire in terms of the physical property. However, the length of plating time needs further consideration for the clinical application of electroless plating.

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.

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.