• 한국미생물·생명공학회지
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• 제24권3호
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• pp.311-315
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• 1996

A cytotoxic material was produced by strain No. 5-99 which was isolated from soil. Analyzing the cell wall components, LL-diaminopimelic acid was identified. From the existance of glycine in the cell wall, this strain was identified to Streptomyces sp. which has cell wall chemotype I and peptidoglycan type A3 connected by glycine. So, we named this strain to Streptomyces sp. YJB-599. The Active material was purified through solvent extraction, silica gel column chromatography and crystallized to needle-shaped white -crystal. Analyzing the structure of this crytal by instrumental analysis and database, it was determined to genistein.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.558-561
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• 2005

In-situ photopolymerization of alkyl acrylate monomers in the presence of a nematic fluid provides a cellular matrix of liquid crystalline droplets in which the chemical structure of the encapsulating polymer exerts control over the alignment (anchoring) of the liquid crystalline molecules. Control is obtained by variation of the alkyl side chains and through copolymerization of two dissimilar monofunctional acrylates. Two monofunctional acrylates with opposing tendencies on copolymerization provide control over the tunability of anchoring over a wide temperature range. Using various acrylates we show that a uniform vertical alignment can be achieved over a large area. Utilizing this technique and a nematic with negative dielectric anisotropy, we have fabricated highly flexible liquid crytal based devices, with high contrast and fast response time, without using any alignment layer.

• 한국재료학회지
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• 제27권1호
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• pp.19-24
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• 2017

This paper is concerned with a test method that can be used to investigate the parameters of the Johnson-Cook constitutive model. These parameters are essential for accurately analyzing material behavior under impact loading conditions in numerical simulation. Ti-6Al-4V alloy (HCP crytal structure) was used as a specimen for the experiments. In the $10^{-3}-10^3/s$ strain rate range, three types of experimental methods (convention, compression and tension) were employed to compare the differences using MTS-810, SHPB and SHTB. Finite element analysis results when applying these parameters were displayed along with the experiment results.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.459-462
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• 2001

Interface effects on properties of NTC thermistors having Mn-Co-O spinel crytal structure system are analyzed by a mixing rule in case of mixed types and layered types between CuO and $Al_{2}O_{3}$ added compounds. With adding CuO and $Al_{2}O_{3}$, The compounds form completely solid solution and their resistance and B constant are changed due to the variation of conduction electrons by their ionic substitutions. The properties of mixed NTC thermistors are depended on the logarithmic mixing rule by a dispersed phase and they show slightly lower values due to the lattice mixing affect in compared with calculated values. The resistance of layered NTC thennistors is depended upon the series mixing rule containing the value of an interface layer and effected by the variation of its thickness, and it is changed rapidly to the logarithmic mixing rule by the connection between two layers with increasing the interface layer.

• 한국재료학회지
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• 제3권4호
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• pp.344-351
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• 1993

폴리(에틸렌 테레프탈레이트 -코-1,4-시클로헥실렌 디메틸렌 데레프탈레이트), P(ET-CT), 공중합체의 결정구조를 CPMAS NMR분광법을 이용하여 해석하였다. 결정화 시료에서 메틸렌기에 의한 공명 피크를 CT와 ET성분으로 분리시켜 분석한 결과, 0-20 몰%의 CT조성을 갖는 공중합체는 bulky한 CT성분이 PET결정격자에서 배제되고 66-100 몰 100%의 CT조성을 갖는 공중합체는 PCT결정격자 내부에 ET성분이 부분적으로 혼입되는 것을 확인할 수 있었다. 이와 같은 결정구조의 공중합 조성 의존성은 ET와 CT의 반복단위 길이와 결정격자의 크기가 다르기 때문인 것으로 추정된다.

• 대한화학회지
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• 제17권2호
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• pp.105-114
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• 1973

몰포리노치오세미카바자이드의 결정 구조가 X-선 해석에 의하여 결정되었다. 세포 상수는 a=4.19(2), b=6.56(2), c=26.67(4)$A^{\circ}$ 이고, 단위 세포는 4분자를 포함하며, 공간 군은 $P2_12_12_1$이다. 원자좌표치는 최소자승법으로 정밀화하였으며 R값은 651개의 관측 반사를 써서 계산한 결과 0.07이다. 아미노 질소 원자는 a-축에 평행한 2회의 나선 축에 의하여 옮겨지는 다른 분자의 황원자와 3.48 및 3.49$A^{\circ}$의 수소결합을 하고 있으며 아미노 질소 원자는 a-축에 평행한 2회의 나선 축에 의하여 옮겨지는 다른 분자의 아미노 질소 원자와 3.04${\AA}$의 수소결합을 하고 있다. 이들 3개의 수소결합은 분자들을 2회의 나선축 부근에 배열하게 한다. 수소결합 이외로 분자들을 연결하는 힘은 van der waals의 힘이다.