• Bulletin of the Korean Chemical Society
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• 제15권11호
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• pp.976-980
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• 1994

The sensitivity factors and the error propagation factors are defined for the three-parameter ellipsometry (TPE). The sensitivity factor is useful for understanding the nature of the TPE measurements in connection with determination of the optical properties and the thickness of a film. On the other hand, the error propagation factors provide a quantitative tool for predicting the optimum condition for TPE experiments. Their usefulness is demonstrated for the passive film formed on nickel in aqueous solution.

• Bulletin of the Korean Chemical Society
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• 제12권5호
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• pp.477-483
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• 1991

In the three-parameter ellipsometry (TPE), also known as reflectance-ellipsometry, the ellipsometric measurements, ${\Psi} and {\Delta}$, are combined with the reflectometric measurement, R, to determine the optical parameters and the thickness of a light-absorbing thin film. The constant ${\Psi}, {\Delta}$ and R surfaces are analyzed graphically to understand the nature of the TPE solutions. A sensitivityanalysis is shown to be useful not only for identifying the film properties which affect most the TPE measurements, but also for estimating errors in film properties arising from the uncertainties in measurements.

• 한국기계가공학회지
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• 제5권1호
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• pp.27-32
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• 2006

Thermoplastic elastomer(TPE) has many advantages such as high flexibility, high elasticity and high elongation, etc. TPE is easily molded as plastic materials, therefore, many TPE parts are applied as home appliances and mechanical parts. However, its mechanical properties would be changed by injection molding conditions such as melt temperature, mold temperature, injection pressure and holding pressure, etc. In this study, the influences of the injection molding condition on the mechanical properties as tensile strength, hardness of thermoplastic vulcanizates(TPVs), which is one of the TPE, were investigated. By the injection molding experiment, the molding's tensile strength and hardness was influenced on the melt temperature and composition ratio of PP and EPDM. The morphology of moldings were shown by the scanning electron microscope.

• 폴리머
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• 제29권2호
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• pp.204-210
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• 2005

플라스틱 디스플레이 기판용으로 사용하기 위하여 무색, 투명하면서 유연성, roll-to-roll 공정, 내열성과 저 열팽창계수 특성을 갖출 수 있는 폴리이미드에 대한 연구를 하였다. 3,3',4,4'-oxydiphthalic anhydride(ODPA), 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), sulfonyldianiline(3-SDA), aminophenoxybenzene(TPE-p, TPE-q, TPE-r)과 bis[4-(3-aminophenoxy)phenyl]sulfone(m-BAPS) 등을 사용하여 무색 투명한 폴리이미드를 합성하고 광학적 특성을 UV spectrophotometer, colormeter와 hazemeter를 이용하여 측정하였다. 열팽창계수(CTE)를 낮추기 위하여 층상실리케이트로 나노복합화하였다. 무색투명한 폴리이미드 필름은 440 nm에서 $89\%$ 이상의 광투과도와 yellow index(YI) 값이 7 이하의 우수한 광학 특성을 보였다. 나노복합화한 폴리이미드 필름은 층상실리케이트가 효과적으로 박리되어 층상실리케이트의 함유량이 증가함에 따라 열팽창계수가 감소하는 효과를 보였다.

• 동의생리병리학회지
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• 제32권4호
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• pp.261-270
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• 2018

The aim of this study was to evaluate the antitumor activities of Typhae pollen (TP) by confirming in vitro cytotoxicity and in vivo anti-tumor and immune-modulatory effect with anti-cachexia effect. The MTT assay is used in HepG2 cell to detect potential cytotoxic activities of aqueous extract of Typhae pollen (TPe). After HepG2 tumor cell implantation, eight mice per groups were assigned to six groups. Three different dosages of TPe (500, 250 and 125 mg/kg) were orally administered in the amount of $10m{\ell}/kg$ and sorafenib also administered 20mg/kg, every day for 35 days from 28 days after the tumor cell implantation. We observed the changes on body weights, tumor volume and weights, lymphatic organ, serum interferon $(IFN)-{\gamma}$ levels, splenocytes and peritoneal NK cell activity, splenic tumor necrosis factor $(TNF)-{\alpha}$, interleukin $(IL)-1{\beta}$, IL-10 contents. Periovarian fat weights, serum IL-6 levels, thicknesses of deposited periovarian adipose tissue and mean diameters were also detected to monitor the tumor-related anticachexic effects. In tumor masses, the immunoreactivities of cleaved caspase-3 and cleaved poly (ADP-ribose) polymerase (cleaved PARP) - apoptotic marks, cyclooxygenase-2 (COX-2), inducible nitric oxide synthases (iNOS) and tumor necrosis factor $(TNF)-{\alpha}$ were additionally observed by immunohistochemistry. The results were compared with sorafenib. Decreases of COX-2 were demonstrated in sorafenib and TPe treated mice and also increases of iNOS in tumor masses were observed in TPe, not in sorafenib. TPe increased periovarian fat pad weights compared with tumor-bearing controls and sorafenib treated mice. TPe showed increases of splenic $TNF-{\alpha}$, IL-10 and $IL-1{\beta}$, serum $IFN-{\gamma}$ and NK cell activities corresponding to increases of spleen weights, lymph node weights and non-atrophic changes of lymph nodes. Our results show oral treatment of TPe 500, 250 and 125 mg/kg has potent in vitro and in vivo antitumor activities through modest cytotoxic effects, immunomodulatory effects and apoptotic activities in HepG2 tumor cells. In addition, TPe can prevent cancer related cachexia.

• 한국유변학회:학술대회논문집
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• 한국유변학회 2003년도 춘계학술발표회 논문집
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• pp.21-24
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• 2003

No Abstract, See Full Text

• Elastomers and Composites
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• 제45권3호
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• pp.170-187
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• 2010

열가소성 탄성체(thermoplastic elastomer, TPE)는 학술적 기초 및 응용은 물론이고 산업적, 상업적으로 매우 중요한 유기 소재의 하나이다. TPE는 블록 공중합체뿐만 아니라 많은 다른 고분자분야에서도 중요한 한 영역으로 생각할 수 있다. 가황 고무가 갖고 있는 성질과 열가소성 플라스틱이 보이는 성질을 동시에 갖고 있기 때문이다. 또한 블록과 그라프트 공중합체, 이들 혼합물, 가황 물질에서 비롯된 일련의 성질을 보여주기 때문이다. 이 소재의 중요성은 출판되는 간행물(논문, 특허, 보고서 등)의 수에서도 알 수 있다. 'thermoplastic elastomer'를 키워드로, 열가소성 탄성체의 개념이 들어간 간행물의 숫자를 SciFinderScholar를 이용하여 조사한 결과, 1939년 ~ 2010년 7월 10일 사이에 18,508편에 이르렀으며, 특히 1990년 중반부터 그 숫자가 기하급수적으로 늘었다. 열가소성 플라스틱의 성질과 가교탄성체의 성질을 동시에 갖고 있는 TPE의 영역을 설명할 때 과학적, 기술적, 상업적인 관점을 모두 고려해야 한다. 본 보문에서는 TPE의 역사적인 관점을 먼저 설명하고, 화학적, 구조적 및 모폴러지 연구 동향을 다루고자 한다. 또한 주요 제조법과 현대적 분석 기술을 다룰 것이다. 이어 TPE의 성질과 가공성, 유기소재 사이에서의 입지와 응용에 대해도 분석한 후, 향후의 발전 방향에 대하여 논의하고자 한다.

• 공학교육연구
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• 제17권1호
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• pp.50-56
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• 2014

본 연구는 설계교과목에서 팀 프로젝트를 수행한 학생들을 대상으로 팀의 성격구성과 팀 창의성 간의 관계를 파악하기 위해 수행되었다. 공대생 249명, 총 48개 팀을 대상으로 성격 5요인에 대해 성격요인 상승(TPE) 및 성격요인 다양성(TPD)이 팀 창의성과 어떤 관계를 갖는 지를 알아보았다. 그 결과, 외향성과 개방성은 성격요인 다양성(TPD)이 팀 창의성과 관련이 있는 반면, 성실성, 호감성, 신경증은 성격요인 상승(TPE)이 팀 창의성과 관련이 있었다. 본 연구결과의 제한점과 후속연구를 위한 제언이 논의되었다.

• 한국전기전자재료학회논문지
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• 제33권5호
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• pp.400-404
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• 2020

In this paper, we study the correlation between the crystallinity of semiconductive compounds for eco-friendly power cables and the dispersive properties of carbon black. The crystal structure of the polymer material is advantageous for mechanical properties and heat-resistance. However, the polymer acts as an inhibitor to the dispersibility of carbon black. The purpose of this study is to develop a TPE semiconductive compound technology. The high heat resistance and ultra-smoothness characteristics which are required for high voltage and ultra-high voltage cables should be satisfied by designing and optimizing the structure of a non-crosslinking-type eco-friendly TPE semiconductive compound. The application of excess TPE resin was found to not only inhibit the processability in the compounding process, but also reduced the dispersion properties of carbon black due to higher crystallinity. After the crystallinity of the compound was identified through DSC analysis, it was compared with the related dispersion characteristics. Through this analysis and comparison, we designed the optimal structure of the eco-friendly TPE semiconductive compound.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.375-376
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• 2006

Thermoplastic elastomer(TPE) can be molded by conventional injection molding. Therefore TPE injection molding could be analyzed by commercial flow analysis software. However there are a little of gaps on CAE simulation results and practical molding. In this study, the properties of TPE were measured and applied to CAE simulation for comparing the simulation flow pattern and real flow pattern. The pattern that was controlled by injection time was match. The pattern that was controlled by injection stroke and rate was not match.