• Bulletin of the Korean Chemical Society
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• 제27권12호
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• pp.2058-2060
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• 2006

• 한국결정성장학회지
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• 제5권1호
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• pp.37-43
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• 1995

실리콘의 용액성장을 위해서는 우선 적절한 용매의 선택이 선행되어야 한다. 이 논문에서는 최소한의 실리콘을 (1 atomic%) 고용할 수 있는 온도를 여러 용매를 대상으로 계산하였다.

• 멤브레인
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• 제8권1호
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• pp.11-21
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• 1998

The study on penetrant transport in glassy polymers has been actively pursued for decades because of its growing significance in polymer processing and related applications such as not only membranes, but corrosion protective coatings, microlithography, microelectronic fabrication, etc. In membranes application of polymeric materials, successful utilization requires understanding of how solvents penetrate, swell, and sometimes dissolve polymeric materials under various environmental conditions, as their permselecdve performance is significantly affected by it. The expose of polymer membranes to solvents may result in the structural failure due to mechanical softening, embrittlement or crazing.

• Bulletin of the Korean Chemical Society
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• 제7권6호
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• pp.416-421
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• 1986

The solvent coordination effect on the excited state processes of Mg(II)- and Zn(II)-phthalocyanines has been described. The triplet state of these compounds decays with mixed first and second order kinetics or mainly second order kinetics depending on the solvents used. The first order component of the rate constants decrease along with the series, dimethylsulfoxide (5-coordinated), 1-chloronaphthalene (4-coordinated) and piperidine (6-coordinated), while the second order rate constant is dependent on the diffusion rate constant of the solvents. The excited state quenching by methylviologen or p-benzoquinone is discussed. And ion recombination rate constant is given.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.574-577
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• 1995

Solvatochromic effect and hydrogen bonding interaction of NPNOH, NPNO- and NPNOR were investigated. Electronic transition energies of the dyes were plotted against empirical solvent polarity parameters, Taft's π* and Reichardt's ET(30). Good correlations were observed when the excitation energies were plotted against the energy calculated by multiple linear regression method which was developed by Taft. There is an intrinsic difference between betaine for ET(30) polarity scale and the azoderivative, which is derived from the specific hydrogen bond incurred with probe molecules and solvents. The hydrogen bonding plays a very important role for stabilization of an excited state molecule by solvents especially when a solute possesses a negative charge as with NPNO-.

• Bulletin of the Korean Chemical Society
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• 제12권3호
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• pp.271-273
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• 1991

Poly (N-vinylcarbazole) was obtained spontaneously by 1,1,2,2-tetracyanocyclopropylstyrene(1) in polar solvents such as dichloromethane and acetonitrile at room temperature. The polymerization reactions were faster in more polar solvent and were not proceeded in less polar solvents such as chloroform and diethyl ether. The formation of poly (N-vinylcarbazole) was explained by bond-forming initiation theory, in which the initiating species are zwitterionic tetramethylene intermediates.

• Journal of Photoscience
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• 제12권1호
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• pp.51-54
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• 2005

The electronic excitationenergy quenching of 2, 5-diphenyl-1, 3, 4-oxadiazole (PPD) by Carbon tetrachloride ($CCl_4$) in different solvents viz, n-hexane, n-heptane, toluene, benzene, cyclohexane, 1, 4- dioxane has been carried out at room temperature to understand the role of quenching mechanism. The Stern-Volmer plots have been found to be linear. As probability of quenching per encounter 'p' is less than unity, and the activation energy for quenching '$E_a$' is greater than the activation energy of diffusion '$E_d$', it is inferred that the fluorescence quenching mechanism is not due to material diffusion alone.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권6호
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• pp.476-481
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• 2004

The aim of this study was to formulate a sustained release system for indomethacin (IND) with rosin gum obtained from a pine tree. Rosin microparticles were prepared by a disper­sion and dialysis method without the addition of surfactant. In order to investigate the influence of solvents on the formation of colloidal microparitcles, various solvents like ethanol, DMF, DMAc, and acetone were used. The rosin microparticles containing IND were characterized by X­ray differactometry (XRD) and differential scanning calorimetry (DSC). The morphologies of rosin microparticles observed by scanning electron microscopy (SEM) were spherical. The solvents used to dissolve rosin significantly affected the drug content and drug release rate of IND. The release behaviors of IND from the rosin microparticles were dependent on the drug content and size of the particles. Rosin micorparticles with a higher drug content and of a larger particle size had a slower drug release rate. Also, the IND release rate from the rosin microparticles could be regulated by the rosin content in the microparticles. From these results, rosin microparticles have the potential of being used as a sustained release system of IND.

• 공업화학
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• 제21권1호
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• pp.93-97
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• 2010

친핵성 첨가반응에 의한 극성 용매(NMP, DMSO, DMF, m-cresol etc.)에 용해성을 갖는 이온성 액체(1,3-dimethylimidazolium methylsulfate, I-DMS)로 도핑된 폴리아닐린(PAN/I-DMS)을 합성하였다. 극성 용매 내에서 PAN/I-DMS의 용해도는 3~6 wt%/vol.을 나타내었고, PAN/I-DMS films의 전기전도도는 $10^{-2}{\sim}7S/cm$를 나타내었다. PAN/I-DMS는 HCl로 도핑된 폴리아닐린(PAN/HCl)과 dimethylsulfate (DMS)로 도핑된 폴리아닐린(PAN/DMS)에 비하여 $160^{\circ}C$에서 열적 안정성과 전기 전도성이 우수함을 볼 수 있었다. 극성 용매 내에서의 용해도와 전기 전도도 증가 현상을 극성 sulfonate group과 극성 용매간의 상호 작용으로 설명하였다.

• 생약학회지
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• 제41권2호
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• pp.136-140
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• 2010

This study was carried out to utilize non-toxic solvents instead of harmful solvents for the TLC(Thin Layer Chromatography) identification test of herbal medicines. It is recommended not to use harmful solvent such as chloroform at a viewpoint of clean analysis. In this study, we revised the identification test of 10 items in the Korea Pharmacopoeia(KP) and the Korean Herbal Pharmacopoeia(KHP) such as Cornus officinalis S. containing the harmful solvents on the developing solvent and established identification test that is utilized non-toxic solvents by HPTLC(High Performance Thin Layer Chromatography).