• Journal of the Korean Graphic Arts Communication Society
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• v.21 no.1
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• pp.81-90
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• 2003

To understand the thermoresponsive volume phase transition of an N-isopropyl acrylamide(NIPA) gel on water, the solubility parameter of neutral NIPA gel was determined by swelling the gel with various solvents. Water was found not to be a good solvent for NIPA gel. Equilibrium swelling curves of NIPA gel were respectively obtained by immersing in pure water, ethanol, n-propanol and some mixed solvents. On adding a small amount of alcohols to water, volume phase transition of NIPA gel in water was changed. Phase transition temperature of this gel was decreased with the increase of the carbon number of alcohol.

• Journal of Conservation Science
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• v.5 no.2 s.6
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• pp.15-24
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• 1996

Th)s study was carried out of the historical characters and textile coservations for Mrs. Danha Lee's Wonsam. As the textile material was silk, dry cleaning method was suggested. The solvents for dry cleaning were n-hexane, n-decane, and benzene. During the second cleaning process, the dry soap(HI-TECH, 120:1, volume ratio) was added to the mixed solvents. The reaction's temparature was $20^{\circ}C$, and the reaction's time was 30 minuutes. It seemed to be a gift for hot from the Royal Family because of the attachment of pheonlx hungbae. This wonsam was decorated symmetrically by gold weaving yarn, the basic fabric was green silk satin with glorius letters and floral patterns. It was made on the 17th C and the oldest thing among them.

• Journal of the Korean Chemical Society
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• v.12 no.3
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• pp.114-120
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• 1968

Fe-EDTA complex, which is easily formed when Fe salt and EDTA.2Na are mixed in the aqueous medium, is found to be a very effective catalyst in the dehydropolycondensation of aminophenols. In the dehydropolycondensation of aminophenols, the catalyst, Fe(Ⅲ)-EDTA complex (higher oxidation state) is reduced to less stable Fe(Ⅱ)-EDTA complex (lower oxidation state), and the latter is easily oxidized by air to the original higher oxidation state complex, therefore the catalytic action of Fe-EDTA complex is found to be recycled effectively. Under the catalytic action of the above mentioned complex, p-aminophenol is polymerized in the aqueous medium to form the oligomers of p-aminophenol, which the degree of polymerization to be 5 or more. The oligomers formed contain partly quinone nucleus as well as amino and hydroxyl groups. In this study, the effects of the solvents and characteristics of the oligomers are discussed. These types of polymerizations catalyzed by the metallic chelate compounds are considered to be very closely related to the reactions in the living matters.

• Journal of the Korean Chemical Society
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• v.16 no.2
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• pp.100-105
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• 1972

The thermal degradation of poly (${\alpha}$-methyl styrene) in several mixed solvents (toluene-n-butylalcohol, toluene-sec-butylalcohol, toluene-kerosene, toluene-methyl ethyl ketone) without hydroquinone, and in with the addition of the hydroquinone, was studied at temps. of $165^{\circ}{\sim}205^{\circ}C$. The velocity constant of degradation (k), and the activation energy (E) were calculated for each solvent. As results, k decreased with the increase of the volume-fraction of poor solvent in both systems, whereas E either showed no perceptible change or it increased with the volume-fraction of poor solvents. these results were discussed.

• Bulletin of the Korean Chemical Society
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• v.1 no.3
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• pp.101-104
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• 1980

A sequential copolypeptide with repeating unit sequences, in which a glycyl residue is flanked progressively by two ${\gamma}$-benzyl-L-glutamyl residues, has been synthesized by poymerizing p-nitrophenyl ester of ${\gamma}$-benzyl-L-glutamyl-${\gamma}$ -benzyl-L-gutamyl-glycine. Polymers obtained were characterized by viscosity and infra-red spectral data. The highest molecular weight obtained was 21,000. Molecular conformation in solid state was found to be a mixed form of and |${\beta}$-structure. Polymers obtained were insoluble in the most of the organic solvents except in a strong acid like dichloroacetic acid, but in binary mixtures of solvents such as dichloroacetic acid-ethylene dichloride or dichloroacetic acid-chloroform, they were soluble within certain ranges of solvent compositions.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.215-218
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• 2002

Poly(vinyl alcohol)(PVA)는 1924년 W. O. Herrmann과 W. Haehnel이 Poly(vinyl esters)를 caustic soda 용액에서 비누화하여 합성한 뒤 많은 연구 및 사용되어지고 있는 고분자이다. 환경친화적이고, 인체에 무해하여 인공관절, 콘택트 렌즈 등에 이용이 되고 있다. 특히 구조가 선형적이고 zig-zag구조를 가지기 때문에 고강도, 고탄성을 갖는 섬유의 제조가 가능한 소재이다[1]. PVA섬유의 제조는 용매를 이용한 습식방사 및 겔방사로 섬유를 제조한다. (중략)

• 대한예방의학회:학술대회논문집
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• 2005.10a
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• pp.386-386
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• 2005

• Textile Coloration and Finishing
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• v.6 no.3
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• pp.37-43
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• 1994

Commercial Poly(ethylene terephthalate) (PET) filaments were treated in solvents mixtures such as benzyl alcohol/perchloroethylene(BA/PER), benzyl alcohol/trichloroethylene(BA/TRI), benzyl alcohol/ethylene chloride(BA/EC), metha nol/perchloroethylene(ME/PER), and methanol/trichloroethyle(ME/TRI). Swelling of PET in solvent mixtures showed rapidly in the middle range of mixture ratio. Contribution of swelling of each component to total swelling of binary mixtures with increasing treated time was generally showed in proportion to the mixture ratio of the each component in dependence of the extend of swelling.

• Bulletin of the Korean Chemical Society
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• v.6 no.1
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• pp.19-23
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• 1985

Solvolysis of 1-adamantyl chloride, -bromide and -tosylate have been studied in methanol-acetonitrile mixtures. Rate maxima were found for 1-adamantyl bromide and tosylate at 80-90 % methanol mixtures. The rate maximum observed was interpreted as a result of cooperative enhancement of cation and anion solvation. 1-Adamantyl tosylate had small cation solvation but had extensive anion solvation. It was concluded that the Y scale based on adamantyl tosylate is superior to others since it varies in a wide range especially for weakly ionizing medium.

• Journal of Pharmaceutical Investigation
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• v.10 no.3
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• pp.14-19
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• 1980

The dissociation constant of erythrosine in the mixed solvent systems of water-alcohols and water-acetone at various pH and in concentration media were determined by spectrophotometric method. Methanol, ethanol, and acetone were employed as solvents and studied the changes of pK values of erythrosine according to the kind and change of concentration of organic solvent which is mixed into water solution. The effect of organic solvent on pK is negligible at 40% while in the case of above 40% mixing, it is not negligible.