• Bulletin of the Korean Chemical Society
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• 제24권6호
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• pp.757-762
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• 2003

Since theoretical investigations of gas phase clusters enable the evaluation of intrinsic molecular properties and intermolecular interactions, one can predict the macroscopic properties of bulk matter, from a microscopic determination of the properties of individual atoms, molecules, or clusters. Based on the insights obtained from theoretical investigations of the properties of a large number of cluster systems (ranging from simple water clusters to large π-systems), we have investigated the properties of various novel molecular systems including endo/exohedral fullerenes, nanotori, nonlinear optical materials, ionophores/receptors, polypeptides, enzymes, organic nanotubes, nanowires, and electronic and nano-mechanical molecular devices. The present minireview highlights some of the interesting results obtained in the course of our extensive theoretical investigations of clusters and nanomaterials.

• 분석과학
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• 제7권1호
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• pp.79-89
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• 1994

메트릭스 격리 분광법으로 적외선 흡수 스펙트럼을 구하여 아세토니트릴과 다른 유기분자로서 퓨란, 피롤, 피롤리딘, 티오펜, 테트라하이드로티오펜 및 아세트알데히드 등과의 상호작용에 대하여 조사하였다. 매트릭스 물질로는 Xe을 주로 사용하였다. 아세토니트릴은 피롤 및 티오펜과는 상호작용을 강하게 하고, 피롤리딘 및 아세트알데히드와는 상호작용이 거의 없는 것으로 관찰되었다.

• Journal of Photoscience
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• 제10권2호
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• pp.181-184
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• 2003

Photochemical reactions of some organic molecules on titanium dioxide were investigated in methanol. A methanolic solution of trans-cinnamic acid and titanium dioxide was irradiated with 300 nm UV lamps for 24 h to afford methyl cinnamate. In the case of trans-cinnamamide, the major product was found to be 3-phenylpropionamide, i.e., a saturation product of ethylenic double bond. However, irradiation of urocanic acid, caffeic acid, ethyl cinnamate, trans-chalcone, trans-cinnamonitrile, trans-stilbene or trans, trans-1,4-diphenyl-1,3-butadiene on titanium dioxide under the same conditions did not give any noticeable products. Meanwhile, when irradiated some aromatic aldehydes, such as trans-cinnamaldehyde, l-naphthaldehyde, and 2-naphthaldehyde in methanol, vicinal diols and alcohols derived from the diols were produced. On the other hand, irradiation of 9-anthraldehyde and titanium dioxide in methanol afforded only alcohols, in which diol was not observed.

• 한국염색가공학회지
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• 제10권5호
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• pp.56-62
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• 1998

In the prior study, the dyeing behaviors of Milling Cyanine 5R on silk fiber in aqueous dyeing liquor including small amount of organic compounds were investigated. The most effective compound was acetophenone which increased dye uptake as well as dyeing rate. In this study, the role of the acetophenone in dyeing of silk with Milling Cyanine 5R was studied. By addition of acetophenone into the dye solution, the molar absorptivity of Milling Cyanine 5R increased, and the wavelength of maximum absorption was shifted to longer wavelength, namely bathochromic shifted. This shows that the acetophenone prevents the dye to aggregate, and increases the number of monomeric dye molecule relative to the dye solution without acetophenone. This fact was also confirmed by the increase of the permeation rate of the dye through cellulose semipermeable membrane from the dye solution including the acetophenone. From these results, the acetophenone acts as a prohibitor of dye aggregation, increases the number of monomeric dye molecules even at relatively low temperature, and makes the dyes penetrate into the fiber easier.

• Carbon letters
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• 제12권2호
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• pp.81-84
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• 2011

A novel experimental set-up allowing quantitative determination of the adsorption capacity of gas molecules on a surface under high-vacuum conditions is introduced. Using this system, the toluene adsorption capacities of various carbon nanostructures were determined. We found that for a give surface area, the adsorption capacities of toluene of multi-walled carbon nanotubes and nanodiamonds were higher than that of activated carbon, which is widely used as an adsorbent of volatile organic compounds. The adsorption of toluene was reversible at room temperature.

• Journal of Photoscience
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• 제5권4호
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• pp.143-148
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• 1998

Photoaddition reactions of ο-benzoquinones to some organic molecules were ivestigated to yield three types of photoadducts. Irradiation (350nm UV light) of a dichloromethane solution of tetrahal-1, 2- benzoquinones and 1, 4-diphenylbutadiene yielded 1, 3-dienes, which was found to be used to synthesize 1-phenylphenanthrenes. The 1, 3-dienes were also produced, when irradiated tetrahalo--1, 2-benzoquinones and 1,4-dipenylbut-1-en-3-yne in the similar conditions, which was applied to get 9-phenylphenanthrenes. An enolic compound come from the tautomerization of dibenzoylmethane was found to add to ο-benzoquinones to give, 1, 4-dioxenes and 1, 5-diketones as the major products. Although depenylbutadiyne did not add to ο-benzoquinones, diphenylacetylene added to ο-benzoquinones to give $\rho$-quinomethanes as well as two isomeric $\rho$-quinomethanes. One-way photoisomerism was observed for two isomeric $\rho$-quinomethanes.

• Rapid Communication in Photoscience
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• 제3권4호
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• pp.64-66
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• 2014

Synthesis of a deuterium-labeled derivative of nitrospirobenzopyran (NSP), one of representative photochromic compounds, has been described. Four deuteriums were successfully introduced on 1-methyl and ${\alpha}$-methyne relative to spiro-carbon in the title compound with more than 95atom%D purity. Main photodegraded products of NSP were two oxindoles in acetonitrile, and additional products were formed in poly(isobutyl-methacrylate) films possibly due to restricted molecular motion in polymer matrix. Quantitative HPLC analysis revealed that partial introduction of deuterium to NSP brought a noticeable isotope effect, recognizable enhancement in photo-resistivity of NSP, i.e.,8.3% in solutions and 29% in polymeric films.

• 한국인쇄학회지
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• 제12권1호
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• pp.67-80
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• 1994

Electrochrominm is a phenomenon of reversible change in optical properties produced electrochromically. Among the several organic type electrochromic displays(ECD), the one based on viologen solution is still attractive and become of the possibility for choosing various colors by introducing different substituents in viologen molecules. But these has been rather a severe problem in this type of ECD, which is the erasing failure caused by the recrystallized molecule sticking to the display electrode.This paper was investigated on developing a new class of composite materials which consists of the mixture of BV2+ . 2BF4-, TMPD with TBABF4 as supporting electrolyte to overcome the above mentioned problem of viologen solution.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.91-94
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• 1997

$\alpha$-sexithienyl($\alpha$-6T) thin films were deposited by Organic Molecular Beam Deposition(OMBD) technique, where the $\alpha$-6T was synthesized and purified by the sublimation method. The thin films of the $\alpha$-6T were deposited under various deposition conditions. The effects of deposition rate, substrate temperature. and vacuum pressure an the formation of these films have been studied. The molecular orientations of $\alpha$-6T films were investigated with the polarized electronic absorption spectroscopy. The molecules in the $\alpha$-6T film deposited at a low deposition rate under a high vacuum were aligned almost perpendicular to the substrate. The film deposited at an elevated substrate temperature (~9 $O^{\circ}C$) showed higher conductivity than the film deposited at room temperature.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.365.3-366
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• 2002

New and improved preparations of structurally modified nucleosides are important goals in synthetic organic chemistry because of the potential utility of these compounds as synthetic precursors of many biologically active molecules in cells. In our program to synthesize the bioactive nucleosides, such as AdoHcy hydrolase inhibitors and cyclic adenosine diphosphoribose(cADPR) analogues. (omitted)