Dextran Gel 의 분자구조

구윤모,Phillip C . Wankat ( Yoon Mo Koo,Phillip C . Wankat ) 생화학분자생물학회 1988 BMB Reports Vol.21 No.1

Dextran, a main constituent of Sephadex gel, is a linear homopolymer (polysaccharide) composed almost exclusively of the monomeric unit, α-D-glucopyranose, linked mainly by 1-6 glucosidic bonds. As a basic building block of dextran, the conformation of α-gentiobiose (6-0-α-D-glucopyranosyl-α-D-glucopyranose) in vacuum was studied by the technique of the consistent force field. We presented the procedures of identifying the position of each atoms in a reference coordinate system. The molecular structure of a Sephadex gel was simulated as two sets of cylinders: one for a unit of α-gentiobiose and the other for a cross-linking bridge. The structural dimension of a dextran gel (Sephadex G-25) was expressed by the radius and the length of those cylinders: a cylinder with a radius at 2.54 Å and a length of 5.61 Å for α-gentiobiose and a cylinder with a radius of 1.57 Å a length of 4.84 Å for the cross-linking bridge.

4H-SiC 소자의 JTE 구조 및 설계 조건 변화에 따른 항복전압 분석

구윤모,조두형,김광수,Koo, Yoon-Mo,Cho, Doo-Hyung,Kim, Kwang-Soo 한국전기전자학회 2015 전기전자학회논문지 Vol.19 No.4

Silicon Carbide(SiC) has large advantage in high temperature and high voltage applications because of its high thermal conductivity and large band gap energy. When using SiC to design power semiconductor devices, edge termination techniques have to be adjusted for its maximum breakdown voltage characteristics. Many edge termination techniques have been proposed, and the most appropriate technique for SiC device is Junction Termination Extension(JTE). In this paper, the change of breakdown voltage efficiency ratio according to the change of doping concentration and passivation oxide charge of each JTE techniques is demonstrated. As a result, the maximum breakdown voltage ratio of Single Zone JTE(SZ-JTE), Double Zone JTE(DZ-JTE), Multiple Floating Zone JTE(MFZ-JTE), and Space Modulated JTE(SM-JTE) is 98.24%, 99.02%, 98.98%, 99.22% each. MFZ-JTE has the smallest and SZ-JTE has the largest sensitivity of breakdown voltage ratios according to the change of JTE doping concentration. Additionally the degradation of breakdown voltage due to the passivation oxide charge is analyzed, and the sensitivity is largest in SZ-JTE and smallest in MFZ-JTE, too. In this paper, DZ-JTE and SM-JTE is the best efficiency JTE techniques than MFZ-JTE which needs large doping concentration in short JTE width. Silicon Carbide(SiC)는 높은 열전도도와 넓은 밴드갭 에너지로 인해 고온과 고전압 소자로 사용하는데 큰 장점을 가지고 있는 물질이다. SiC를 이용하여 전력반도체소자를 제작할 경우, 소자가 목표 전압을 충분히 견딜 수 있도록 Edge Termination 기법을 적용하여야한다. Edge Termination 기법에는 여러 가지 방안이 제안되어왔는데, SiC 소자에 가장 적합한 기법은 Junction Termination Extension (JTE)이다. 본 논문에서는 각 JTE 구조별 도핑 농도와 Passivation Oxide Charge 변화에 따른 항복전압의 변화를 살펴보았다. 결과적으로 Single Zone JTE (SZ-JTE)는 1D 시뮬레이션 값의 98.24%, Double Zone JTE (DZ-JTE)는 99.02%, Multiple-Floating-Zone JTE (MFZ-JTE)는 98.98%, Space-Modulated JTE (SM-JTE)는 99.22%의 최대 항복전압을 나타내었고, JTE 도핑 농도 변화에 따른 최대 항복전압의 민감도는 MFZ-JTE가 가장 낮은 반면 SZ-JTE가 가장 높았다. 또한 Passivation Oxide 층의 전하로 인해 소자의 항복전압의 변화를 살펴보았는데, 이에 대한 민감도 역시 MFZ-JTE가 가장 낮았으며 SZ-JTE가 가장 높았다. 결과적으로 본 논문에서는, 짧은 JTE 길이에서 높은 도핑 농도를 필요로 하는 MFZ-JTE보다 DZ-JTE와 SM-JTE가 실제 소자 설계에 있어 가장 효과적인 JTE 기법으로 분석되었다.

Molecular Structure of Dextran Gel

구윤모,Koo, Yoon-Mo,Wankat, Phillip C. 생화학분자생물학회 1988 한국생화학회지 Vol.21 No.1

Sephadex 젤의 주 구성원인 dextran은 주로 1-6 glucosidic 결합에 의해 연결된 단위체, ${\alpha}$-D-glucopyranose로 이루어진 선형 homopolymer (polysaccharide)이다. dextran의 기본구조를 이루는 ${\alpha}$-gentiobiose (6-0-${\alpha}$-glucopyranosyl-${\alpha}$-D-glucopyranose)의 conformation을 consistent force field 방법을 사용하여 연구하였다. 기준좌표계에 있어서 각 원자들의 위치를 나타내는 방법을 제시하였다. Sephadex 젤의 분자구조를 두개의 원주로써 모사하였는데, 하나는 ${\alpha}$-gentiobiose, 다른 하나는 cross-linking bridge를 나타내었다. dextran 젤 (sephadex G-25)의 구조적 크기를 이들 원주의 반지름과 길이로써 표시하였는데, ${\alpha}$-gentiobiose는 반지름 2.54 $\dot{A}$ 길이 5.61 $\dot{A}$, cross-linking bridge는 반지름 1.57 $\dot{A}$, 길이 4.84 $\dot{A}$ 이었다. Dextran, a main constituent of Sephadex gel, is a linear homopolymer (polysaccharide) composed almost exclusively of the monomeric unit, ${\alpha}$-D-glucopyranose, linked mainly by 1-6 glucosidic bonds. As a basic building block of dextran, the conformation of ${\alpha}$-gentiobiose (6-O-${\alpha}$-D-glucopyranosyl-${\alpha}$-D-glucopyranose) in vacuum was studied by the technique of the consistent force field. We presented the procedures of identifying the position of each atoms in a reference coordinate system. The molecular structure of a Sephadex gel was simulated as two sets of cylinders: one for a unit of ${\alpha}$-gentiobiose and the other for a cross-linking bridge. The structural dimension of a dextran gel (Sephadex G-25) was expressed by the radius and the length of those cylinders: a cylinder with a radius at 2.54 $\dot{A}$ and a length of 5.61 $\dot{A}$ for ${\alpha$}-gentiobiose and a cylinder with a radius of 1.57 $\dot{A}$ a length of 4.84 $\dot{A}$ for the cross-linking bridge.

연구발표논문초록 ( 분리기술 (Ⅱ) ) : 비선형 , 독립등온성을 갖는 등용매용리크로마토그래피의 scaling 방법

구윤모 ( Yoon Mo Koo ) 한국화학공학회 1988 춘계학술발표회 Vol.- No.-

Radius and Length of Sephadex G Gel Fibers

Yoon-Mo Koo(구윤모) 한국생물공학회 1989 KSBB Journal Vol.4 No.1

홍천강 생태하천 복원사업의 경제적 가치

구윤모 ( Yoon Mo Koo ),강형식 ( Hyeong Sik Kang ),이미숙 ( Mi Suk Lee ) 한국환경생태학회 2014 한국환경생태학회지 Vol.28 No.1

본 연구는 최근 홍천강의 생태적 기능을 되살리기 위해 계획 중인 생태하천 복원사업의 경제적 편익을 정량적으로 추정하는 것을 목적으로 하고 있다. 생태하천 복원사업의 결과물은 시장에서 거래되는 재화가 아니기 때문에 가격을 이용한 가치 측정에 어려움이 있으므로, 사용가치 및 비사용 가치에 대한 지불의 사액을 분석하는 조건부 가치측정법을 적용하였다. 또한 지불의 사액이 0인 응답자들을 고려한 스파이크 모형을 추가적으로 이용하였다. 분석 결과 사업지 인근에서는 가구당 연간 3,300원~4,628원, 비사업지에서는 가구당 연간 1,308원~2,929원의 지불의사가 있었다. 이를 우리나라 전체로 확대할 경우, 홍천강 생태하천 복원사업의 경제적 편익은 현재가치로 약 976억 원~2,163억 원에 이를 것으로 판단된다. The goal of this study is to estimate economic benefit of restoring ecological stream of Hong Cheon river. The benefit is determined by estimating willingness-to-pay for the value of Hong Cheon river because it is a non-market good which is difficult to be measured in terms of monetary value. Specifically, the spike model, one of the contingent valuation methods, is used to distinguish respondents having zero willingness-to-pay for Hong Cheon river. The results show that a household located near the Hong Cheon river is willing to pay 3,300~4,628 Korean Won per year, while a household not located near the Hong Cheon river is willing to pay 1,308~2,929 Korean Won per year. Thus, total benefit of restoring ecological stream of Hong Cheon river is estimated as 97.6~216.3 billion Korean Won.

Lipase 를 생산하는 재조합 E . coli 의 phage 에 의한 용균

문윤희,구윤모 ( Yun Hee Moon,Yoon Mo Koo ) 한국화학공학회 1995 화학공학의이론과응용 Vol.1 No.1

Trichoderma reesei Rut C-30 유래 cellulase 에 의한 고급폐지재생에 관한 연구

한우석,구윤모 ( Woo Seok Han,Yoon Mo Koo ) 한국화학공학회 1998 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.36 No.5

Deinking of office-waste paper using crude cellulase from Trichoderma reesei Rut C-30 was studied, and compared with enzymatic deinking with commercial enzyme, Novozym 342, and conventional chemical deinking method using sodium hydroxide. Maximum brightness and freeness were obtained when 2units of the crude cellulase(CMCase activity unit) was used per gram oven dry paper. Physical strengths af the pulp, deinked with crude cellulase, showed similar behaviors with the brightness and the freeness, but decreased at higher crude cellulase concentration. The recovery yield decreased with the increase of crude cellulase concentration. The brightness and the freeness of deinked pulp using Rut C-30 crude cellulase were better than those using Novozym 342. Enzymatic deinking method gave better results than conventional chemical deinking method in deinking efficiency and physical strengths of deinked pulp. The ratio of endoglucanase and exoglucanase of crude cellulase, known to be an important parameter in determining deinking efficiency and the physical properties, was comparable to that of commercial enzyme.

Trichoderma reesei 를 이용한 섬유소 분해 효소의 생산에 있어서 혼합탄소원의 영향

남주헌,구윤모,윤현식 ( Joo Heon Nam,Yoon Mo Koo,Hyun Shik Yun ) 한국균학회 1998 韓國菌學會誌 Vol.26 No.2

자외선에 의한 E . coli Double - Lysogen 의 용해에 대한 수학적 모델

박순석,구윤모 ( Soon Suk Park,Yoon Mo Koo ) 한국화학공학회 1995 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.33 No.3

A mathematical model was proposed in order to explain the lytic behaviors of the UV-irradiated E. coli double-lysogen[P90c/(λHL1,434)]. The UV dosage that lysogen had received was represented by the normal distribution, so that the survival, lysis and death fractions of the irradiated lysogen were described by the function of UV dosage. Using this model, the characteristics of the protein production and the cell lysis of the irradiated double-lysogen were studied, Finally, the optimum conditions for the cell lysis were predicted by changing the related parameters.