• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2479-2482
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• 2010

Using a pinhole-type glass nozzle equipped for a corona-excited supersonic expansion (CESE), precursor 2,6-dichlorotoluene seeded in a large amount of inert carrier gas helium was discharged to produce jet-cooled but electronically excited benzyl-type radicals. The visible vibronic emission spectrum was recorded with a long-path monochromator to observe vibronic bands in the $D_1{\rightarrow}D_0$ electronic transition of benzyl-type radicals. The spectral analysis revealed the generation of not only the 2,6-dichlorobenzyl radical as a typical product, but also the o-chlorobenzyl radical as an unexpected species, which indicates the possible molecular rearrangement in eliminating a chlorine atom from the benzene ring. A possible mechanism is proposed for the formation of the o-chlorobenzyl radical from the precurs or in the gas phase.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.433-438
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• 1998

수소와 물 사이의 촉매교환공정은 중수 생산 및 삼중수소 분리를 위해 개발되어 왔다. 국산 소수성 촉매를 이용하여 새로운 튜브형 촉매탑을 고안하고, 수소와 물 사이의 수소 동위원소 분리를 실증하는 실험을 수행하였다. 국산 소수성 측매는 Styrene Divinyl Benzene Copolymer 담체에 백금을 담지한 촉매로써, 모양은 실린더형이며, 직경이 4mm이다. 촉매 작용을 하지 않는 충전물은 wire mesh ring(3mmx3mm)이고, 튜브는 PCI사 membrane(PVDF)이다. 촉매합의 직경은 2.5cm, 높이는 35cm였고, 온도는 333k, 압력은 0.1MPa였다. 기상 촉매반응만 시켰을 때 촉매탑이 정상상태에 도달되는데 약 3-5시간이 필요했으며, 액체 흐름이 있는 경우가 훨씬 짧았다. 촉매탑의 분리성능을 평가하기 위해 수소 동위원소 분리실험에서 얻은 기체 농도를 이용하여 물질전달계수(Kya)를 계산하였다. Kya는 0.2-0.5 sec$^{-1}$였으며, 액체와 기체 유속에 의해 크게 영향을 받았다.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.181-189
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• 1998

In order to investigate the effect of base oil composition on the electronic insulating oil's performances, an experimental study has been conducted using different oils. Owing to their properties, like lower pour point and gas absorbing, naphthenic base oils are used more often than paraffmic base oils for the electronic insulating oil application. Naphthenic and paraffinic base oils are significantly different in their aromatic hydrocarbon content. In this paper, PXE(para xylyl ethane), LAB(linear alkylbenzene), C13 aromatic hydrocarbon mixture and C17 aromatic hydrocarbon mixture are investigated regarding their influence on insulating oil's performances. According to present study, breakdown voltage decreased with increasing aromatic lydrocarbon content in a deep dewaxed paraffmic base oil. However, any changing in the dissipation factor was not recognizable at small treated level. Furthermore, the volume resistance was not influenced by aromatic hydrocarbon content. The gassing tendency was found as a highly sensible property, changing with treating aromatic hydrocarbons. The higher benzene ring content in the hydrocarbon, the better gassing tendency.

• Journal of the Korean Chemical Society
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• v.14 no.2
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• pp.147-153
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• 1970

Band assignments in the infrared absorption spectra of the four substituted Urea compounds, Fenuron (3-phenyl-1,1-dimethyl urea), OMU (3-cyclooctyl-1,1-dimethyl urea), Herban (3-(hexahydro-4,7-methanoidan-5-yl)-l,1-dimethyl urea), and Monuron (3-(p-chlorophenyl)-1,1-dimethyl urea), are made by analyzing the spectra obtained with various solvents. The results suggest that Fenuron and Monuron, each of which contain an unsaturated benzene ring, have a strong tendency to bond through both the amino group and the carbonyl oxygen. Herban and OMU, however, exhibit a much greater change in strength of the carbonyl bond than of the amino bond. It means that a strong hydrogen bonding occurs only at the carbonyl oxygen in the compounds.

• Journal of Surface Science and Engineering
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• v.25 no.4
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• pp.173-180
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• 1992

The effects of the stabilizing additives such as NaCN, 2-MBT and Thiourea on bath decom-position, plating rate and surface morphology have been studied. Bath stability was increased in the order of an additive-free bath, and NaCN-, 2-MBT-, and Thiourea-stabilized baths. The sta-bilizing effects may be attributed to the stability of Cu(II) -complexes. The plating rate is the re-verse order of the bath stability. Accelerative effect of 2-MBT in proper quantity(0.3mg/$\ell$) may be explained by visualizing it absorbed through benzene ring or sulfur atom on portions of the sub-strates. The strong bond of the complexing part of the molecule to nearby chelated copper ions would tend to accelerate plating by making it easier for the Cu2+ -ligand bond to be broken. Sur-face morphologies of copper deposits depend on the bath additives. Electroless copper deposits from the 2-MBT stabilized baths are finer than the deposits from the NaCN- and Thiourea- stabi-lized baths due to the strong adsorption on the substrates.

• Journal of Microbiology
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• v.35 no.1
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• pp.66-71
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• 1997

To investigate the biodegrading capability of several white-rot fungi isolated in Korea, biodegradation of BTX (benzene, toluene, xylene), phenanthrene and pyrene were tested in fungal cultures. Phanerochaete chrysosporium removed 20-30% of BTX mixture during 21 days of incubation in serum bottle. Coriolus versicolor KR-11W and Irpex lacteus mineralized 10.02 and 8.26% of totla phenanthrene, respectively, which were higher than in other studies with P. chrysosporium. These two strains also showed high mineralization rates (9.2-10.1%) for 4-ring pyrene. I. lacteus metabolized most of the added pyrene and 23.29% was incorporate dinto fungal biomass. Almost 50/5 of the pyrene was converted to polar metabolites and recovered from aqueous phase of culture. These results indicated that some white- rot fungi have higher biodegradability than P. chrysosporium and could be used in bioremediation of aromatic hydrocarbon contaminants in soil.

• YAKHAK HOEJI
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• v.29 no.4
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• pp.183-187
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• 1985

During investigation of the anthelmintic substances against Clonorchis sinensis which are based on the structure of meso-dihydroguairaretic acid, some non-mesoic diaryl butanes were synthesized by Grignard reaction and their anthelmintic activities were determined. In this reaction, an aryl butanone was reacted with benzylmagnesium chloride to produce the corresponding diaryl hydroxybutane which was converted to the corresponding diaryl butane by zinc and hydrogen chloride. The substituents in benzene ring of the diaryl butanes were changed by methylation or demethylation. Among the synthesized substances, 4-phenyl-1-(3, 4-dihydroxyphenyl)-2, 3-dimethylbutane(VII), 4-phenyl-1-(3-hydroxy-4-methoxyphenyl)-2, 3-dimethylbutane(IX) and 4-phenyl-1-(4-hydroxy-3-methoxyphenyl)-2, 3-dimethylbutane(VI) showed strong wormicidal effects against Clonorchis si-nensis in that order. Phenolic hydroxyl group seemed to play a certain role for the wormicidal activity of the diaryl butanes.

• YAKHAK HOEJI
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• v.39 no.6
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• pp.631-635
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• 1995

A series of 3, 4-dihydro-3-oxo-2H-1, 2, 4-benzothiadiazine-1, 1, dioxides with cytotoxic activity against human solid tumors is described. Synthesized compounds showed mild but broad spectrum cytotoxicity in vitro. The lipophilic substituents like alkyl, alkoxy and chloro on benzene ring increased the activity. Also hydrophobic group on 3 or 4 position of benzothiadiazine was important for the activity.

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.83-91
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• 2009

To develop new anticancer agents, 3-allylthio-6-aminopyridazine derivatives were synthesized from maleic anhydrides or phthalic anhydrides by formation of a pyridazine nucleus, dichlorination, allylthiolation and amination. The pyridazine nuclei were obtained by condensing a hydrazine monohydrate with maleic anhydride. An allylthio group as a pharmacologically active group was introduced into one side of a pyridazine ring. Arylalkylamines with benzene or pyridine moieties or heterocycloalkylamines with heterocycle moieties such as morpholine, piperidine, or pyrrolidine were also introduced into the para-position of allylthio pyridazine. These new compounds showed antiproliferative activities against SK-Hep-1 human liver cancer cells in MTT assays. These compounds are thus promising candidates for chemotherapy of hepatocellular carcinomas. Two compounds, 20c and 22a, showed higher potencies for inhibiting growth of hepatocellular carcinoma cells than did K6 ($ID_50$=1.08 mM). This suggests the potential anticancer activity of these two compounds.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.1993-1995
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• 2007

A substitution effect on the electronic transition of bi-substituted benzyl-type radicals was discovered. The origin of the electronic D1 → D0 transition of benzyl-type radicals was red-shifted upon substitution to the benzene ring. For symmetric bi-substituted benzyl-type radicals, it was found that the predicted shift obtained from mono-substituted benzyl-type radicals agreed well with the observation. The reason for this agreement is believed that the substituent contributes independently to the electronic energy. The substitution effect was applied to the symmetric bi-substituted difluoro-, dichloro- and dimethylbenzyl radicals.