• 한국전기화학회:학술대회논문집
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• 1999.10a
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• pp.27-27
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• 1999

• Journal of the Korean Chemical Society
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• v.37 no.12
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• pp.987-994
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• 1993

Inductive and resonance effects play an important role in determining carbony) stretching frequencies of ketones. Hydrogen bonding, dielectric effects, and steric effects are all factors which determine the carbonyl stretching frequency, νC=O of ketones in solution. The $ν_{C=O}$ frequencies were shifted by approximately 27$cm^{-1}$ each by substituting to a phenyl group for a methyl group in acetone. The $ν_{C=O}$ frequency for ketones shifted differently in various solvents and increased with increasing the volume ratio of the ketones in water solutions. The $ν_{C=O}$ frequency for ketones shifts continously at constant concentration of ketone in solutions of $(CH_3)_2SO/CCl_4$and$CHCl_3/CCl_4$ with changing of the mole ratio of two solvents. The $ν_{C=O}$ frequency was also affected by changing concentration in either $CCl_4$ or $(CH_3)_2SO$ solution and in either $CCl_4$or $CHCl_3$ solution.

• Journal of the Korean Chemical Society
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• v.19 no.6
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• pp.454-462
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• 1975

The photodegradation of polystyrene and polyethylene was studied utilizing several additives to promote photooxidation. Polymer films with small amount of additives were irradiated with ultraviolet lamps in Rayonet Photochemical Reactor. The progress of photodegradation was followed by measuring the intensities of carbonyl and hydroxyl stretching bands in infrared spectra as well as the viscosity changes. It was found that the increase of carbonyl or hydroxyl peaks was proportional to the decrease of the molecular weight of polymers under study. Iron(II, III) complexes of dithiocarbamate and their analogs showed good results.

• Journal of the Korean Chemical Society
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• v.35 no.1
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• pp.90-95
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• 1991

A method for the selective syntheses of alkyl (alkoxymethyl)benzoates from halobenzyl halides by two steps in one pot process is described. In the first step, benzyl halide moiety is etherified with alkoxide anion in alcohol by Williamson ether process. In the second step, aryl halide moiety is carbonylated to give alkyl (alkoxymethyl)benzoate with alcohol, Na$_2$CO$_3$, CH$_3$I, and carbon monoxide (1 atm) in the presence of a catalytic amount of Co$_2$(CO)$_8$ in excellent yield.

• Korean Journal of Food Science and Technology
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• v.12 no.2
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• pp.88-96
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• 1980

Reaction conditions in the amino-carbonyl reaction, and the effect of amino acids on the reactivity of amino-carbonyl reaction were investigated. Results obtained are as follows : 1. When the pH of the reaction mixture was increased above the isoelectric point of an amino acid, a significant increase in the color intensity was observed. 2. The color intensity increased gradually up to 1 : 1 of the molar ratio of reactants. This result was interpreted to show that sugar and free amino group combined in 1 : 1 ratio. 3. Amino-carbonyl reaction showed a significant time and temperature-dependences. The activation energy at 0.2 M glucose and 0.2 M glycine system was 37.5 Kcal/mole. 4. Among amino acids tested, glycine, lysine and $\beta$-alanine caused a significant increase in the color intensity, but acidic amino acids showed the least color intensity. The latter was interpreted to show that one of carboxyl groups of acidic amino acid has an inhibiting effect on the reactivity of the amino group. 5. The color intensity of sugars tested was in the order of xylose>arabibose>fructose>glucose>maltose>lactose.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.317-318
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• 2003

전기활성고분자인 poly(vinylidene fluoride)(이하 PVDF로 약기)와 전기비활성 고분자와의 혼화성블렌드에서 외부전장이 이 블렌드의 상분리거동에 미치는 영향을 조사하기에 적합한 전기비활성고분자를 찾은 결과 측쇄에 C=O기를 갖는 poly(ethyl methacrylate)(이하 PEMA)와 주쇄에 C=O기를 갖는 poly(1,4-butylene adipate)(이하 PBA로 약기)가 좋은 후보 고분자로 사용가능함을 보였다. 측쇄에 C=O기를 갖는 고분자인 PMMA와 PVDF와의 블렌드에서 PVDF의 융점보다 상당히 높은 온도인 35$0^{\circ}C$ 이상의 온도에서 lower critical solution temperature (이하 LCST로 약기) 거동을 보이는 것으로 알려져 있기 때문에 [1] 실제로 이들 블렌드계에서 열분해를 배제하면서 LSCT거동을 실험적으로 관찰하기는 불가능하다. (중략)

• Applied Biological Chemistry
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• v.37 no.3
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• pp.216-220
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• 1994

Organoanisyltitanium compounds which have chlorine or isopropoxy group as ligand were synthesized and purely isolated. These new compounds were proved to be stable at $0^{\circ}C$ under argon atmosphere for some weeks. They react readily at low temperature with carbonyl compound, especially aldehyde and ketone, to coresponding alcohols. In competition reaction of aldehyde/ketone pair these organotitanium species showed complete aldehyde selectivity.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.75-88
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• 2014

본 연구에서는 비선형 Poisson-Boltzmann 식의 해를 구할 수 있는 웹 기반 EPBS를 이용하여 이온채널의 전하 분포와 유전률이 이온채널의 이온선택성에 미치는 영향에 대해 알아본다. 모델로 사용한 이온채널은 이온채널과 유사한 구조를 갖는 합성 단백질인 고리형 펩타이드 나노튜브와 자연계에 존재하는 Gramicidin A 이다. 계산 결과로부터 용매인 물과 단백질의 유전율 차이에 의해 이온이 이온채널을 통과할 때 반응장이 생성되며, 이는 이온과 상호작용을 통해 이온 종류에 관계없이 이온 통과를 방해하는 에너지 장벽을 형성함을 알 수 있다. 한편, 두 이온채널 부분 전하, 특히 골격에 존재하는 카르보닐기의 쌍극자 모멘트에 의해 이온채널 내부에는 0 보다 작은 정전기 퍼텐셜이 형성된다. 이온채널 내부의 총 정전기 퍼텐셜은 이온채널의 부분 전하에 의한 정전기 퍼텐셜과 유전률 차이에 의한 반응장의 합으로 나타나며, 계산 결과 0 보다 작은 값을 갖는다. 이로부터 본 연구에서 사용된 두 종류의 이온채널이 양이온에 선택성이 있음을 알 수 있다.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.414-418
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• 1985

A general synthesis of ${\alpha},\{\beta}$-unsaturated carbonyl compounds has been developed by oxidation of t-allylic alcohols. In simpler system, pyridinium chlorochromate oxidation affords the functionality transposed carbonyls in excellent yields, making the reaction a useful and versatile synthetic method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.12 no.1
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• pp.11-17
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• 1999

Aging characteristics of the crosslinked polyethylene have been measured after applying electrical, thermal and combined stresses. ICP and FT-IR measurements confirmed diffusion of low molecular weight components such as antioxidant and presence of carbonyl group. Carbonyl group of aged crosslinked polyethylene under combined stress was detected by FT-IR. As deterioration of the crosslinked polyethylene progresses, crystallinity degree and density decrease. Also, dielectric properties have been measured by tan $\delta$ and $\varepsilon$$_{r}$ measurements. The three-parameter Weibull distribution was found to be the best suited among other probabilistic distribution representing the dielectric breakdown strength of aged crosslinked polyethylene. The scale parameter and location parameter decreases as the applied stress increases. The shape parameter increases as the stress increases.s.