• 한국인쇄학회지
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• 제21권1호
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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.

• 보존과학회지
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• 제5권2호
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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.

• 한국미생물·생명공학회지
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• 제19권4호
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• pp.368-371
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• 1991

Ethylene glycol, glycerol, sorbitol 그리고 sucrose가 Bacillus stearothermophilus가 생산하는 cyclodextrin glucanotransferase(CGYase)의 열안정성에 미치는 영향을 조사하였다. Glycerol, sorbitol 그리고 sucrose가 CGTase의 열안정성에 효과가 있었다. 이 효과는 첨가물의 농도와 밀접한 관계가 있었다. n-Butanol, 1,4-dioxane그리고 n-octane과 같은 유기 용매에서 CGTase의 열안정성을 조사하였다. 1,4-dioxane 과 n-octane은 CGTase의 열안정성을 증가시켰다. 특히, n-octane에서 CGTase를 $75^{\circ}C$에서 90분간 정치시킨 후에도 원래 효소활성의 81를 유지하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.15-18
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• 2001

Perdeuterated hexaflouroacetylacetonato-ytterbium [Yb(SOL)-D)$_3$] complexes were synthesized by the keto-enol tautomerism reaction of Yb(SOL-H)$_3$ in methanol-d$_4$in methanol-d$_4$in order to reduce the radiationless transition to the ligands. The luminescence properties of Yb(SOL-D)$_3$complex were measured in the following anhydrous deuterated organic solvents ; Methanol-d$_4$, THF-d$\sub$8/, PO(OCH$_3$)$_3$ and DMSO-d$\sub$6/. The intensity, lifetime and quantum efficiency of the luminescence in DMSO-d$\sub$6/ were superior to those in other deuterated solvents. It was suggested that the anhydrous DMSO-d$\sub$6/ might be the most appropriate solvent for the liquid laser material of Yb(SOL-D)$_3$ complex.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.640-643
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• 2001

Perdeuterated hexaflouroacetylacetonato-ytterbium [Yb(SOL-D)$_3$] complexes were synthesized by the keto-enol tautomerism reaction of Yb(SOL-H)$_3$in methanol-d$_4$in order to reduce the radiationless transition to the ligands. The luminescence properties of Yb(SOL-D)$_3$complex were measured in the following anhydrous deuterated organic solvents ; Methanol-d$_4$, THF-d$_{8}$, PO(O$CH_3$)$_3$and DMSO-d$_{6}$. The intensity, lifetime and quantum efficiency of the luminescence in DMSO-d$_{6}$ were superior to those in other deuterated solvents. It was suggested that the anhydrous DMSO-d$_{6}$ might be the most appropriate solvent for the liquid laser material of Yb(SOL-D)$_3$complex.complex.

• 한국전기전자재료학회논문지
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• 제13권12호
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• pp.1045-1050
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• 2000

Perdeuterated hexaflouroacetylacetonato-ytterbium [Yb(HFA-D)$_3$]complexes were synthesized by the keto-enol tautomerism reaction of Yb(HFA-H$_3$) in methanol-d$_4$in rder to reduct the radiationless transition to the ligands. The luminescence properties of Yb(HFA-D)$_3$complex were measured in the following anhydrous deuterated organic solvents ; Methanol-d$_4$, THF-d$_{8}$, PO(O$CH_3$)$_3$and DMSO-d$_{6}$. The intensity, lifetime and quantum efficiency of the luminescnce in DMSO-d$_{6}$ were superior to those in other deuterated solvents. It was suggested that the anhydrous DMSO-d$_{6}$ might be the most appropriate solvent for the liquid laser material of Yb(HFA-D)$_3$complex.complex.

• 환경위생공학
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• 제16권3호
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• pp.72-79
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• 2001

The selective catalytic oxidation of toxic aromatic solvents (benzene, toluene, ethylbenzene, and styrene) and their mixtures were studied on a $Pt/{\;}{\gamma}-Al_2O_3$ catalyst at temperature ranging from $160~350^{\circ}C$. The deep conversion of aromatic solvents was increased as the inlet concentration was decreased and the reaction temperature was increased. The reactivity increases in order benzene > toluene > ethylbenzene > styrene. In mixture, remarkable effects on reaction rate and selectivity have been evidence ; the strongest inhibition effect is shown by styrene and increase in a reverse order with respect to that of reactivity. The inhibition effect was increased in order styrene > ethylbenzene > toluzene > benzene. This trend is due to the competition adsorption between the two or three reactants on the oxidized catalyst. Also, the deep conversion change of benzene was a small in tertiary mixtures(including of benzene and styrene) comparing with conversion characteristics of binary mixture with styrene. This result was due to small concentration of styrene. which had very strong inhibition effect.

• Macromolecular Research
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• 제8권5호
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• pp.209-214
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• 2000

Polyenaminonitriles containing cycloaliphatic and aliphatic units were prepared by interfacial or solution polymerization reaction of p-bis(1-chloro-2,2-dicyanovinyl) benzene (1) with 4-aminobenzyl-amine, 1-(2-aminoethyl)piperazine, 2-(aminomethyl)pyrrolidine and 4-(aminomethyl)piperidine. The chemical structure of the polymers was confirmed through a syntheses of the model compound. The resulting polymers possessed inherent viscosities of 0.29∼0.62 dL/g and they were easily soluble in polar aprotic solvents and common organic solvents. Thermal properties of the polymers such as curability and stability were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and infrared spectroscopy. The polymers exhibited a large exotherm in DSC analyses and underwent a curing reaction around 340-370$\^{C}$ to form insoluble materials. The polymers showed 70-80% residual weight at 600 $\^{C}$ under nitrogen.

• Macromolecular Research
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• 제15권4호
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• pp.302-307
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• 2007

The living radical polymerization of methyl methacrylate (MMA) by atom transfer radical polymerization, (ATRP) employing a $Fe(II)X_2/diphenyl-2-pyridyl$ phosphine (PyP) catalytic system (X=Cl, Br), was investigated using several initiators and solvents at various temperatures. Most of the polymerizations with the PyP ligand were well controlled, with a linear increase in the number average molecular weights ($M_n$) vs. conversion, with relatively low molecular weight distributions ($M_w/M_n=1.2-1.4$) throughout the reactions. The measured weights matched those of the predicted values. The ethyl-2-bromoisobutyrate (EBriB) initiated ATRP of MMA, with the $Fe(II)X_2/diphenyl-2-pyridyl$ phosphine catalytic system (X=Cl, Br), was better controlled in p-xylene at $80^{\circ}C$ than the other solvents used in this study.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1415-1420
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• 2005

The spectral interferences of OH from aqueous solvents in ICP-AES have been studied and eliminated using a cryogenic argon trap. The prominent lines of Bi I 306.772 nm, Al I 309.271 nm, and V II 310.230 nm, which are very seriously overlapped with the OH band, were examined. With an extended torch and high tangential flow of 20 L/min, water vapor from air entrainment was prevented. The combination of a condenser and argon cryogenic trap was able to eliminated most of water vapor carried by the argon sample gas. Removal of OH spectral interference could extend the linearity of the calibration curve 5-10 times on the lower concentration for ICP-AES. Interference Equivalent Concentration (IEC) has been reduced to 5.6, 5.9, and 12.4 times for Bi, Al and V, respectively.