• Carbon letters
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• 제16권4호
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• pp.223-232
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• 2015

This review presents current progress in the preparation methods of liquid crystalline nano-carbon materials and the liquid crystalline spinning method for producing nano-carbon fibers. In particular, we focus on the fabrication of liquid crystalline carbon nanotubes by spinning from superacids, and the continuous production of macroscopic fiber from liquid crystalline graphene oxide.

• 한국해양공학회지
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• 제8권2호
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• pp.93-104
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• 1994

Recently in the design of super tankers or LNG carriers which transport a large amount of liquid in the cargo holds, the structural damage due to liquid sloshing becomes an important problem. The impact pressure from sloshing is most violent when the liquid motion of a partially filled tank is in resonance with the motion of a ship. In this paper the sloshing natural periods in liquid cargo tanks are estimated for partially filled tanks with various geometries. Especially the sloshing periods of baffled tanks which are often installed to reduce liquid motion and sloshing forces are calculated. A variational method is adopted to analyze the baffled tank of arbitrary filling depth of liquid. In this approach the liquid domain is divided into several subdomains in which the analytic solutions are potential energy are calculated from the velocity potentials in eachsubdomain. By minimizing the Hamilton's functional, the sloshing natural periods are estimated and the results are compared with experimental and numerical results.

• Journal of Advanced Marine Engineering and Technology
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• 제19권1호
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• pp.36-44
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• 1995

Melting characteristics of unrestrained liquid ice in a rectangular vessel with heated top wall were investigated experimentally. The liquid ice, a mixture of ice particles and ethylene-glycol aqueous solution, was adopted as a testing material. During the melting process the liquid ice was drawn by buoyancy to the heated top wall of the rectangular vessel where close-contact melting occured. The melting behavior and melting rate of the liquid ice as well as local/mean heat-transfer coefficient at the heated top wall were observed and measured under a variety of conditions of heat flux and various initial concentration of the aqueous binary solution. It was found that the heat transfer of the heated top wall is remarkably promoted by the close-contact melting, and that the dendritic frozen layer at the lower interface of the liquid ice is formed. Photographic evidence demonstrated that plumes containing solute-rich liquid issued from isolated chimneys within the liquid ice layer where segregation of interstitial channel took place.

• 한국항공우주학회지
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• 제44권4호
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• pp.333-342
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• 2016

액체로켓 추진시스템은 액체 추진제와 액체 산화제의 화학반응을 통해 추력을 발생하는 방식으로써 우주발사체 및 인공위성을 포함한 우주비행체에 광범위하게 적용되고 있다. 일반적으로 사용되는 액체로켓 추진제로는 모노메틸하이드라진/사산화이질소, 액체수소/액체산소 및 RP-1/액체산소 조합 등이 있다. 본 연구의 목적은 액체로켓 추진제의 열화학적 반응을 수치적으로 분석함으로써, 이를 통해 궁극적으로 액체로켓엔진의 설계와 성능에 필요한 유용한 정보를 예측하고자 하는 데 있다. 이를 위해 앞서 언급한 3가지 조합의 연료와 산화제에 대하여 연소반응 후 화학평형상태에 도달했을 때 주요 요소평형반응들의 평형상수 값들을 이용해 최종 생성물의 성분과 화학조성을 계산하였고 그 결과를 이용해 단열화염온도와 로켓성능변수인 비추력을 예측하는 연구를 진행하였다.

• Transactions on Electrical and Electronic Materials
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• 제9권6호
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• pp.251-254
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• 2008

Blue-white reflective cholesteric liquid crystal display was prepared by a unique method of single liquid crystal layer, the combination of yellow color liquid crystal and blue color backplane. The dopant and host combination of chlolesteric liquid crystal affects the color spectrum. The CIE chromaticity coordinates of blue and white are (0.10, 0.16) and (0.29, 0.30), respectively. The relatively low driving voltages of 32 V for blue-white display are obtained.

• 미생물학회지
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• 제29권5호
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• pp.267-269
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• 1991

The hyphal tip laccase of Coprinus congregatus which is a membrane-associated enzyme and shows diffdrdnt banding patterns of PAGE analysis when compared with the enzyme of liquid culture (Choi et al. 1987) has been successfully secreted to culture medium in liquid shake culture by lowering the pH of medium to 4.0. When the fungus is cultivated in YpSs(pH 4.0) liquid, only the hyphal tip laccase is found in the medium after 6 hr incubation and there is no liquid-type enzyme when examined by PAGE analysis.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.263-265
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• 2003

Stressed liquid crystals, SLCs, consist of a lowdensity polymer network dispersed in a nematic host. We induced stress by shearing the material. Alignment layers are not required because the liquid crystal director uniformly aligns along the direction of shear. The shearing stress also eliminates light scattering and results in sub-millisecond switching speeds, making them good candidates for video display applications.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.256-259
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• 2003

The study of confined liquid crystals flourished in the decade of the nineties. Liquid crystals properties have been probed after confinement in well-defined or interconnected geometries as those available in porous media and in polymer networks. In this work we emphasized the power of the nuclear magnetic resonance technique to determine the confined liquid crystal structures. We also present unexpected results on the dependence of the confined liquid crystal configuration on the chain length.

• Journal of Information Display
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• 제11권2호
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• pp.91-93
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• 2010

The shearing effects on the electro-optical properties of a stressed cholesteric liquid crystal were investigated. A photopolymer was dispersed in the cholesteric liquid crystal cell. By carefully choosing the mixing ratio between the liquid crystal and the photoreactive monomer, and by applying suitable mechanical shearing on the substrates, a cholesteric liquid crystal display with a low threshold voltage and no alignment layer was demonstrated.

• Transactions on Electrical and Electronic Materials
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• 제10권1호
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• pp.20-23
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• 2009

Black-white reflective cholesteric liquid crystal display was prepared with two color liquid crystal layers, the combination of yellow color liquid crystal and blue color liquid crystal. The rubbing of cholesteric liquid crystal panel affects the brightness and color spectrum due to increase the planar domain texture. The CIE chromaticity coordinate of white is (0.31, 0.31).