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.

Characterizations of Modified Silica Nanoparticles(I)

Min, Seong-Kee,Park, Chan-Young,Lee, Won-Ki,Seul, Soo-Duk Materials Research Society of Korea 2012 한국재료학회지 Vol.22 No.6

(3-mercaptopropyl)trimethoxysilane (MPTMS) was used as a silylation agent, and modified silica nanoparticles were prepared by solution polymerization. 2.0 g of silica nanoparticles, 150 ml of toluene, and 20 ml of MPTMS were put into a 300 ml flask, and these mixtures were dispersed with ultrasonic vibration for 60 min. 0.2 g of hydroquinone as an inhibitor and 1 to 2 drops of 2,6-dimethylpyridine as a catalyst were added into the mixture. The mixture was then stirred with a magnetic stirrer for 8 hrs. at room temperature. After the reaction, the mixture was centrifuged for 1 hr. at 6000rpm. After precipitation, 150 ml of ethanol was added, and ultrasonic vibration was applied for 30 min. After the ultrasonic vibration, centrifugation was carried out again for 1 hr. at 6000rpm. Organo-modification of silica nanoparticles with a ${\gamma}$-methacryloxypropyl functional group was successfully achieved by solution polymerization in the ethanol solution. The characteristics of the ${\gamma}$-mercaptopropyl modified silica nanoparticles (MPSN) were examined using X-ray photoelectron spectroscopy (XPS, THERMO VG SCIENTIFIC, MultiLab 2000), a laser scattering system (LSS, TOPCON Co., GLS-1000), Fourier transform infrared spectroscopy (FTIR, JASCO INTERNATIONL CO., FT/IR-4200), scanning electron microscopy (SEM, HITACHI, S-2400), an elemental analysis (EA, Elementar, Vario macro/micro) and a thermogravimetric analysis (TGA, Perkin Elmer, TGA 7, Pyris 1). From the analysis results, the content of the methacryloxypropyl group was 0.98 mmol/g and the conversion rate of acrylamide monomer was 93%. SEM analysis results showed that the organo-modification of ultra-fine particles effectively prevented their agglomeration and improved their dispensability.

역내외 현물환, 선물환 및 NDF 거래에 의한 원화 가치 가격발견에 관한 연구

빈기범 ( Ki Beom Binh ),이상민 ( Sang-min Lee ),이원섭 ( Won Seop Lee ) 한국파생상품학회(구 한국선물학회) 2016 선물연구 Vol.24 No.2

본 연구에서는 Hasbrouck(1995, 2002)의 정보공헌도(information share) 기법을 이용하여 역내 외환시장의 원/달러 현물환율과 선도환율, 역외 통화시장의 원/달러 NDF 환율의 장기적 공통추세를 중심으로 한 상호 가격발견의 동학을 분석한다. 분석 결과는 다음과 같다. 첫째 NDF 시장에 비해 역내 외환시장에서의 현물환이나 선물환이 주도적인 가격발견의 기능을 하고 있다. 둘째, 원화 가치는 글로벌 위기시 국내외 정보에 더욱 민감해지는데, 위기의 시기에 있어 NDF의 가격발견 역할이 증대된다. 하지만, 역내 시장의 가격발견상 역할과 비중을 능가하지는 못한다. 결국, NDF 시장이 이른바 왝더독(wag the dog)을 촉발시키는 요인으로 보기 어렵다. 이러한 결과는 NDF 시장에 대한 부정적 인식과 시각을 지닌 시장 참여자나 정책당국자가 참고할 필요가 있다. 나아가, NDF 시장이 원화에 대한 24시간 거래를 가능케 하고, 역내 외환시장의 현물환율이나 선물환율에 대한 가격발견 기능이 있다는 것은 역내 외환 시장에서 주요 환율 지표 결정에 있어 불확실성을 줄이는 역할을 하고 있는 것을 시사한다. Using Hasbrouck`s (1995, 2002) information share method, we examine the mutual price discovery dynamics among Won/Dollar spot, forward, and NDF exchange rates in on- and off-shore FX markets. Our findings include : (i) During the entire period, the mutual price discovery between on-shore FX market and off-shore NDF market are significantly led by on-shore Won-Dollar spot and forward exchange rates. (ii) Within the period around the global crisis, NDF exchange rates have mutual influence on the price discovery, which is expecially greater than the any other period. The results show Won-Dollar spot exchange rate fluctuations during the global crisis are greatly affected by external factors of the international financial markets. Not only that, but off-shore NDF trading promptly reflects the price information of KRW on the factors.

3분과 : 가선집재작업에서의 작업 생산성 및 비용 분석

한원성 ( Won Sung Han ),한한섭 ( Han Sup Han ),김남훈 ( Nam Hun Kim ),차두송 ( Du Song Chu ),조구현 ( Koo Hyun Cho ),민도홍 ( Do Hong Min ),권기철 ( Ki Cheol Kwon ) 한국임학회 2014 한국산림과학회지 Vol.103 No.1

본 연구에서는 임목수확작업에 사용되는 집재기계의 작업효율성을 분석하여 경사가 급한(20° 이상) 작업조건에 적합한 가선계 집재기계를 선정하는데 기초 정보를 제공하고자, 타워야더(RME-300T), 트랙터부착형 집재기(일명: 춘천집재기), 트랙터윈치(FARMI) 등에 의한 집재작업에서의 작업생산성 및 비용을 비교 분석하였다. 평균 흉고직경이 20 cm, 집재거리 60 m, 가로집재거리 10 m, 그리고 기계이용률이 70%인 동일한 작업 조건에서 작업이 이루어질 경우, 타워야더의 1일 집재작업 생산성은 33.04 m3/일, 트랙터부착형 집재기는 38.47 m3/일, 그리고 트랙터윈치는 14.17 m3/일으로 분석되었으며, 이에 따른 집재작업비용은 각각 25,105원/m3, 20,520원/m3, 37,835원/m3으로 나타났다. 동일한 작업조건에서 집재거리에 따른 각 집재기계별 작업효율성을 비교하였을 경우, 집재거리가 40 m 이내로 짧을 경우에는 트랙터윈치에 의한 집재작업이 효율적이며, 40~140 m의 집재거리에서는 춘천집재기가, 140 m 이상의 장거리 집재작업에서는 타워야더가 가장 효율적인 것으로 나타났다. This study was conducted to provide field-based harvesting study information which can be used to select an optimal cable system for certain work conditions on steep grounds (>20° ground slope) in Korea. Toaccomplish this study objectives, we evaluated three cable yarding systems (RME-300T tower-yarder, Chuncheontower-yarder, FARMI tractor winch) working in typical work conditions for their yarding productivity and operational efficiency. Those yarders are commonly used for removing logs or trees on steep grounds in Korea. Under the same work conditions (average DBH of tree to be cut, 20 cm; yarding distance, 60 m; lateral yardingdistance, 10 m; and machine utilization rate, 70%), the average productivities were 33.04 m3/day, 38.47 m3/day, and 14.17 m3/day for RME-300T, Chuncheon tower-yarder, and FARMI, respectively. Our standardized cost comparison study also showed that the yarding cost was highest at 37,835 won/m3 with FARMI, followed byRME-300T at 25,105 won/m3 for the same work conditions. We found the lowest yarding cost with the Chuncheon tower-yarder at 20,520 won/m3 which was resulted primarily from high yarding productivity at theyarding distance (60 m). Our analysis suggested that a small machine such as FARMI could be a low-costyarding machine option for a cable yarding job with a short yarding distance (40 m or less). The Chuncheontower-yarder is well suited for a mid-range yarding distance job in Korea, ranged between 40 to 140 m. Ifyarding distance were longer than 140 m, the RME-300T tower yarder appears to be most cost-effective.

국내외 수용가 맞춤형 수력발전시스템 현대화개발 및 실증

오민환(Min-Hwan Oh),신기석(Ki-Seok Shin),임재황(Jae-Hwang Lim),윤여창(Yeo-Chang Yun),김현아(Hyun-Ah Kim),강석원(Seok-Won Kang),백종명(Jong-Myung Paik),이준용(Jun-Yong Lee) 대한전기학회 2017 대한전기학회 학술대회 논문집 Vol.2017 No.10

ISOLATION AND CHARACTERIZATION OF MOLECULAR MARKER FOR SEVERAL RACES OF PYRICULARIA ORYZAE USING RANDOM AMPLIFIED POLYMORPHIC DNA

Hong, Sun-Min,Bae, Dong-Won,Kim, Mee-Hyang,Shim, Chang-Ki,Kang, Kyu-Young,Kim, Nam-Soo,Kim, Hee-Kyu Plant Molecular Biology & Biotechnology Research C 1994 Plant molecular biology and biotechnology research Vol.1994 No.

Primer 155(GCTGGCGCTG) was the most useful primer with distinctive polymorphic DNA pattern to distinguish between KI races and KJ races. Primer 173(CAGGCGGCGT) showed polymorphic DNA pattern to distinguish isolates of KI-100 race. The specific DNA fragment of 0.6Kb, generated from 88-62 of KJ-201 race by RAPD with primer 412)TGCGCCGCTG), was promising as a molecular marker to identify the isolate.

HSS 기반 초고속 LDPC 복호를 위한 구조

이인기(In-Ki Lee),김민혁(Min-Hyuk Kim),오덕길(Deock-Gil Oh),정지원(Ji-Won Jung) 한국통신학회 2013 韓國通信學會論文誌 Vol.38 No.2B

본 논문은 위성방송 전송 규격인 DVB-S2의 기반 채널 부호로 사용되는 LDPC를 고속 복호를 위해 HSS(Horizontal Shuffle Scheduling) 방식을 기반으로 고속 복호기 구조를 연구하였다. 첫째로 HSS방식에서 발생하는 메모리 충돌을 극복하는 방식을 제시한다. 둘째로 고속 복호를 위해 LUT(Look Up Table)을 이용하는 Sum-Product 알로리즘 대신 min값에서 scaling factor를 곱하는 Normalized Min-Sum 알고리즘을 사용하였으며, 성능 향상을 위해 check node에서 bit node로 입력되는 값의 부호를 확인하여 신뢰성 없는 값을 삭제하는 Self-Correct 방식을 제시하여 sum-product 방식에서 발생하는 bottle neck 현상을 하였다. 마지막으로 고속화를 위한 효율적인 메모리 구조를 제안한다. This paper proposes the high speed LDPC decoder structure base on the DVB-S2. Firstly, We study the solution to avoid the memory conflict. For the high speed decoding process the decoder adapts the HSS(Horizontal Shuffle Scheduling) scheme. Secondly, for the high speed decoding algorithm normalized Min-Sum algorithm is adapted instead of Sum-Product algorithm. And the self corrected is a variant of the LDPC decoding that sets the reliability of a Mc→v message to 0 if there is an inconsistency between the signs of the current incoming messages Mv’→c and the sign of the previous incoming messages Moldv’→c This self-corrected algorithm avoids the propagation on unreliable information in the Tanner graph and thus, helps the convergence of the decoder.Start after striking space key 2 times. Lastly, and this paper propose the optimal hardware architecture supporting the high speed throughput.

Production of Iron-Binding Peptides from Colostral Whey by Enzymatic Hydrolysis

Kim, Sang-Bum,Ku, Min-Jung,Cho, Won-Mo,Ki, Kwang-Seok,Kim, Hyeon-Shup,Nam, Myoung-Soo Korean Society for Food Science of Animal Resource 2010 한국축산식품학회지 Vol.30 No.6

Colostral whey prepared from colostrum (pooled from first six post-partum milkings) was heated for 10 min at $100^{\circ}C$ Heated colostral whey was incubated with 1% enzymes (protein equivalent basis) for 15, 30, 60, 90, and 120 min at $50^{\circ}C$. Papain, pepsin, trypsin, and alcalase produced different degrees of hydrolysis (DH), 10.66%, 12.42%, 10.83%, and 25.31%, respectively, at an incubation time of 120 min. The SDS-PAGE reveals that significant amounts of bovine serum albumin (BSA), ${\beta}$-lactoglobulin (${\beta}$-LG), and ${\alpha}$-lactalbumin (${\alpha}$-LA) survived papain digestion. In contrast, pepsin completely removed BSA but not ${\beta}$-LG present in heated colostral whey. Alcalase completely eliminated BSA, ${\beta}$-LG, and ${\alpha}$-LA. This differential hydrolysis was confirmed by reversed-phase HPLC analysis. Using ion-exchange chromatography, fraction-1 (F-1) was obtained from alcalase hydrolysate at a NaCl gradient concentration of 0.25 M. Reversed-phase HPLC chromatograms of alcalase F-1 showed numerous small peaks, which probably indicate that a variety of new peptides were produced. Iron content of alcalase F-1 was 28.94 ppm, which was the highest among all enzyme fractions, whereas iron content of colostral whey was 36.56 ppm. Main amino acids contained in alcalase F-1 were Thr (15.45%), Glu (14.12%), and Ser (10.39%). Therefore, alcalase can be used to generate good iron-binding peptides in heated colostral whey, and the resulting iron-binding peptides could be suitable as a value-added food ingredient for food supplements.

Effects of pyridoxine on a high‐fat diet‐induced reduction of cell proliferation and neuroblast differentiation depend on cyclic adenosine monophosphate response element binding protein in the mouse dentate gyrus

Yoo, Dae Young,Kim, Woosuk,Yoo, Ki‐,Yeon,Nam, Sung Min,Chung, Jin Young,Yoon, Yeo Sung,Won, Moo‐,Ho,Hwang, In Koo Wiley Subscription Services, Inc., A Wiley Company 2012 JOURNAL OF NEUROSCIENCE RESEARCH - Vol.90 No.8

<P><B>Abstract</B></P><P>In this study, we challenged pyridoxine to mice fed a high‐fat diet (HFD) and investigated the effects of pyridoxine on HFD‐induced phenotypes such as blood glucose, reduction of cell proliferation and neuroblast differentiation in the dentate gyrus using Ki67 and doublecortin (DCX), respectively. Mice were fed a commercially available low‐fat diet (LFD) as control diet or HFD (60% fat) for 8 weeks. After 5 weeks of LFD or HFD treatment, 350 mg/kg pyridoxine was administered for 3 weeks. The administration of pyridoxine significantly decreased body weight in the HFD‐treated group. In addition, there were no significant differences in hepatic histology and pancreatic insulin‐immunoreactive (‐ir) and glucagon‐ir cells of the HFD‐treated group after pyridoxine treatment. In the HFD‐fed group, Ki67‐positive nuclei and DCX‐ir neuroblasts were significantly decreased in the dentate gyrus compared with those in the LFD‐fed mice. However, the administration of pyridoxine significantly increased Ki67‐positive nuclei and DCX‐ir neuroblasts in the dentate gyrus in both LFD‐ and HFD‐fed mice. In addition, the administration of pyridoxine significantly increased the protein levels of glutamic acid decarboxylase 67 (GAD67) and brain‐derived neurotrophic factor (BDNF) and the immunoreactivity of phosphorylated cyclic AMP response element binding protein (pCREB) compared with the vehicle‐treated LFD‐ and HFD‐fed mice. In contrast, the administration of pyridoxine significantly decreased HFD‐induced malondialdehyde (MDA) levels in the hippocampus. These results showed that pyridoxine supplement reduced the HFD‐induced reduction of cell proliferation and neuroblast differentiation in the dentate gyrus via controlling the levels of GAD67, pCREB, BDNF, and MDA. © 2012 Wiley Periodicals, Inc.</P>

소아 알레르기비염의 경제적 부담 평가를 위한 다기관 조사

공도연 ( Do Youn Kong ),김경원 ( Kyung Won Kim ),김우경 ( Woo Kyung Kim ),민택기 ( Taek Ki Min ),박용민 ( Yong Mean Park ),안재억 ( Jae Ouk Ahn ),양현종 ( Hyeon Jong Yang ),염혜영 ( Hye Yung Yum ),윤혜선 ( Hae Sun Yoon ),전유훈 ( 대한소아알레르기호흡기학회(구 대한소아알레르기 및 호흡기학회) 2012 소아알레르기 및 호흡기학회지 Vol.22 No.2

목적: 알레르기비염의 유병률은 전 세계적으로 급격히 증가하고 있으며, 그에 따른 경제적 부담도 증가하고 있다. 그러나, 소아 알레르기 질환이 미치는 경제적 부담에 관한 국내 연구는 제한적이어서 소아 알레르기비염이 환자와 그 가족에게 미치는 경제적 부담을 산출하고자 본 연구를 진행하였다. 방법: 2008년 7월 1일부터 9월 31일까지 서울시 6개 2-3차 의료기관을 방문한 18세 이하 소아 알레르기비염 환자 및 보호자를 대상으로 설문 조사를 진행하였다. 설문을 통해 직접 의료비 (병·의원 진료비, 및 약제비 한방 진료비 및 약제비, 보완/대체요법비), 직접비의료비 (교통비, 환경개선비), 그리고 간접비용 (월 평균 노동 손실)을 조사하였고 그 결과를 질환의 중증도 및 유병 기간에 따라 분석하여 그 차이를 비교하였다. 결과: 모집된 262명의 대상 중 174명(66.4%)이 남자였고, 평균 연령은 6.54세였다. 대상군의 연간 평균 직접 의료비는 177만 원이었고 직접비 의료비는 57만 원이었다. 비록 통계학적 유의성은 없었지만, 알레르기비염의 중증도가 증가할수록 직접 의료비가 증가하는 경향을 보였고, (P=0.053) 유병 기간 또한 직접 의료비의 증가와 유의한 양의 상관 관계를 보였다. (R=0.195, P=0.002) 대상 환자 보호자의 약 17%가 아이의 알레르기비염으로 인해 직장에 결근 또는 조퇴를 경험한 것으로 조사되어 사회적 간접비용을 미루어 생각할 수 있었다. 결론: 알레르기비염이 미치는 경제적 부담은 질환의 중증도가 심할수록, 그리고 유병 기간이 길수록 증가하며, 이는 특히 한방 진료 및 치료비와 보완/대체요법비의 증가에 기인한 것으로 조사되었다. 따라서 알레르기비염으로 인한 경제적 부담을 줄이기 위해서는 환자와 보호자를 대상으로 근거 중심의 치료를 할 수 있도록 지속적이고 체계적인 교육이 필요할 것으로 사료된다. Purpose: The prevalence of allergic rhinitis is rapidly increasing and results in relatively high socio-economic burden on their family and community. However, studies on the economic burden of pediatric allergic rhinitis in Korea are limited. Therefore, we conducted this study to investigate the impact of pediatric allergic rhinitis on economic burden. Methods: Two hundred sixty two children with allergic rhinitis were enrolled in 6 secondary or tertiary medical centers in Seoul from July to September, 2008. We collected data of the economic burden of allergic rhinitis (direct medical costs, direct nonmedical costs, and indirect costs) by face to face questionnaire survey. We compared the economic burden according to the severity and the duration of allergic rhinitis. Results: The mean age of subjects was 6.54 years, and male were 174 (66.4%). Direct medical costs (10,000 Korean Won/yr) were 177.75, and direct nonmedical costs were 57.92. Although, there was no statistical significance, direct medical costs showed increasing trends in severe allergic rhinitis. (P=0.053) In addition, direct medical costs were positively correlated with duration of allergic rhinitis.( R=0.195, P=0.002). About 17% of the parents who care the allergic rhinitis children experienced the work absence due to their child s illness. Conclusion: The economic burdens of allergic rhinitis were positively correlated with the severity and duration of illness. Particularly costs for alternative medicine including oriental medicine` were related with severity and duration allergic rhinitis. Therefore, special efforts for education with evidence based treatment strategy are necessary to decrease the economic burden of allergic rhinitis.