• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.532-536
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• 2010

A study on the volatile organic compounds (VOCs) and low molecular weight (LMW) amount which is contained within bisphenol A polycarbonate (PC) was performed by the solvent extraction with ketone type solvents (acetone, butanone, pentanone). The LMW amount of untreated PC was 2.6 wt%, but the values of treated samples with acetone and pentanone were 0.96 and 1.53 wt%, respectively. Acetone is a more effective solvent than pentanone on the LMW extraction. Methylene chloride (MC) and toluene were certified and quantified by GC-Mass experiments, and the quantitative results indicated the fact that the pentanone was the effective solvent on VOC extraction. Focused on the change of VOCs and LMW amount, the use of co-solvent might be more useful, and the experimental results of co-solvent extraction showed that the optimum condition was 50 : 50 volume percent.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.64-72
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• 2012

Phytophthora root rot has been causing a serious yield loss in pepper production. Since 2004, the year in which commercial cultivars resistant to the disease were firstly commercialized, it has been necessary to introduce the resistance into domestic pepper cultivars for dried red pepper. Therefore, developing molecular markers linked to the resistance is required for an accurate selection of resistant plants and increasing breeding efficiency. Until now, several markers associated with the major dominant gene resistant to Phytophthora root rot have been reported but they have some serious limitations for their usage. In this study, we aimed to develop molecular markers linked to the major dominant gene that can be used for almost of all genetic resources resistant to Phytophthora root rot. Two segregating $F_2$ populations derived from a 'Subicho' ${\times}$ 'CM334' combination and a commercial cultivar 'Dokyacheongcheong' were used to develop molecular markers associated with the resistance. After screening 1,024 AFLP primer combinations with bulked segregant analysis, three AFLP (AFLP1, AFLP2, and AFLP3) markers were identified and converted into three CAPS markers (M1-CAPS, M2-CAPS, and M3-CAPS), respectively. Among them, M3-CAPS marker was further studied in ten resistants, fourteen susceptibles, five hybrids and 53 commercial cultivars. As a result, M3-CAPS marker was more fitted to identify Phytophthora resistance than previously reported P5-SNAP and Phyto5.2-SCAR markers. The result indicated that the M3-CAPS marker will be useful for resistance breeding to Phytophthora root rot in chili pepper.

• Clinical and Experimental Reproductive Medicine
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• v.9 no.1_2
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• pp.69-77
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• 1982

암모니움 썰페이트 분획분리법. 초미량여과. DEAE - 셀루로오즈 및 젤 여과 크로마토그라피법 등을 사용하여 사람의 정액에서 베타 글룩유로니다아제를 분리하였다. 이 효소는 pH4.4와 온도 50${\sim}$$54^{\circ}C$에서 최고의 활동도를 나타내었다. 파라-나이트로페닐-디-글룩유로나이드를 기질로 사용하였을때 Km치는 0.59mM이었다. 또한 이 효소는 수은이온, 구리이온, 은이온에 의해 활동도가 방해되고 반면에 망간이온 및 코발트 이온에 의해서 효소의 활동도가 증가되었다. 세파댁스 G-200 젤여과법에 의해 측정된 사람의 정액 베타글룩유로니다아제의 분자량은 400,000 이었다. 이렇게 정제된 효소는 수정과정 중에서 카페시태시션의 연구에 도움을 주리라고 본다.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.69.1-69.1
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• 2010

장주기 Mira 변광성의 외피층에서 발생하는 SiO 메이저에 대해 non-local한 1차원 수치계산 결과를 처음으로 제시한다. 별의 유체역학적인 맥동모델에서 얻은 시간에 따른 별 주위 가스의 속도, 온도, 밀도 분포를 사용하여 계산하였다. 임의의 속도장을 갖는 구형 분자운에서의 복사전달문제를 풀었던 이전 연구에서 개발한 수치계산코드를 이용하였고, 특정 구간에서 급격한 변화를 겪는 물리량을 잘 반영할 수 있도록 수정하였다. 또한 계산에 사용되는 거대희소행렬을 압축희소행렬로 변환하여 메모리를 절약하였고 비선형방정식의 자코비안을 해석적으로 구하여 계산속도를 향상시켰다. v=1, J=1-0, J=2-1과 v=2, J=1-0 SiO 메이저의 공간분포, 상대세기 등에 대해 이전의 LVG 모델을 이용한 연구결과와 정성적으로 비교 논의한다.

• Journal of the Society of Naval Architects of Korea
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• v.34 no.3
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• pp.113-118
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• 1997

A simulation model and its numerical algorithm for the prediction of time-varying oil pollution region are proposed. Not only forces inducing molecular diffusion of oil but also oil advection due to the ocean surface current are considered in the present unified model Furthermore, an automatic modulation of computational grid is introduced to achieve more practical and effective numerical scheme. Applying the present method to some assumed oil spill cases, quite realistic oil maps are thought to be obtained.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.132-133
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• 2007

반도체 소자의 제조 공정 기술이 발전하고 초고집적화가 됨에 따라 소자 선폭도 급속하게 감소하였다. 이로 인하여 기존의 식각 공정에서 식각 후 남은 잔여 Photoresist residue는 소자 생산에 큰 영향이 없었으나 현재 이러한 잔여물은 초고집적 소자에 치명적인 문제를 발생시킬 수 있다. 본 실험에서는 세정액 분자에 플라즈마 충격을 가하여 세정액을 활성화함으로써 기존의 세정액과의 세정능력을 비교 분석하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.280-282
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• 2001

분자생물학의 급진적 발전은 현대 계통분류학에 큰 변혁을 가져왔다. 특히 유전의 근원물질인 DNA나 RNA를 분리.조작.분석하는 기술의 발전으로 이를 이용만 계통수 제작은 계통생물학의 중요한 실험방법으로 자리잡고 있다. 그 중 염기서열 비교 방법은 현재 유전자 계통수 제작에 가장 널리 이용되는 방법이다. 하지만 이러만 계통수는 각 객체간의 거리만을 표현하고, 객체군간의 차이는 설명하기 힘들다. 본 연구에서는 염기서열의 상대적인 특징(유사도)을 대신하는 염기서열의 총량과 염기 함량 등을 이용해 새로이 분류 기법 중 결정트리 방법에 적응하고, 종 분류의 유전적 모델을 설계한다. 또한 결정트리의 클래스인 종은 상위 클래스들을 포함하고 있어, 본 논문에서는 기존의 결정트리 분류자를 수정한 단계적 결정트기 분류자를 제안한다.

• Korean Journal of Plant Resources
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• v.18 no.2
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• pp.302-308
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• 2005

This study was carried out to obtain the basic informations on the characteristics of gametophytes formation and embryo developement in Dicentra spectabilis. Microspore mother cells developed from archesporial cells, start meiosis when flower bud length reaches around 1 mm, formed tetrahedral type tetrad. The 4 microspores were separated. They were developed to male gametophytes, respectively. Megaspore mother cells were observed when flower bud length was $4{\sim}5\;mm$. The developemental type of megaspore was polygonum and embryo sac was amphitropous. Three large and distinctive antipodals did not degenerated and remained after embryo sac was developed. When the male and female gametophytes was fully developed, the length of stamen and style was very similar or stamen was shorter about 0.5 mm than that of style. This result indicates that self-fertilization can be occurred in this species. After fertilization, developing zygotic embryos showed various stages of development from globular to cotyledonary embryos, and zygotic embryo in seed scattering time seemed to have an early cotyledonary stage.

• Journal of the Korean Chemical Society
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• v.47 no.1
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• pp.38-42
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• 2003

For the purpose of developing new agrochemical fungicides, compound 2 possessing 1,3-thiazole scaffold as well as urea moiety in the structure was designed through molecular modification of lead compound, 2-imino-1,3-thiazoline based on isosterism. The reaction of N-methylthiouea 5 and bromoacetonitrile in ethanol gave 2,4-diimino-1,3-thiazole 4 regioselectively, which was treated with phenyl isocyanates to give the corresponding 7 which is tautomer of 2. The structural assignment of 7 was confirmed by various spectra($^1H$ NMR, $^{13}C$ NMR, FT-IR, HRMS), and X-ray crystallographic data. Compound 8 which is a structural isomer of 7 was formed through thermodynamically unstable intermediate 2,4-diimino-1,3-thiazole 6.

• Journal of Sensor Science and Technology
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• v.9 no.1
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• pp.28-35
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• 2000

In this study, we investigated the characteristics of polyurethane synthesis by simultaneously measuring resonant frequency and resonant resistance with a quartz crystal analyzer. The rapid decrease of resonant frequency was appeared because automatic catalytic reaction was caused by the polyurethane formed in initial stage of polyurethane synthesis. In prepolymer(PP) synthesis, the resonant frequency was slowly stabilized after a rapid decrease at a certain point of time. But in segmented polyurethane synthesis in which chain-extender was involved, the resonant frequency increased again after a rapid decrease at a certain point of time. It was considered that this tendency took place because the chain-extender, 1,4-butandiol, caused a soft segment to change to a hard segment. The resonant resistance was used in the analysis of mechanism. From the results, the characteristics of polyurethane synthesis could be analyzed on-line using a quartz crystal analyzer, and the synthesis mechanism could also be interpreted.