• 한국대기환경학회지
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• 제17권1호
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• pp.57-66
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• 2001

Gas phase photocatalytic oxidation of tetrachloroethylene (PCE) under 370 nm ultra-violet irradiation was investigated with TiO$_2$ catalyst. During the photocatalytic oxidation of PCE vapor several kinds of intermediate were produced, and the reaction pathways were proposed on the basis of the production sequency of the intermediates. The intermediates in the pathways of PCE oxidation were hexachloroethane, pentachlotoethane, 1, 1, 2-trichloroethane, carbon tetrachl-oride, dichloroacetylchloride, chloroform, 1,1-dichloroethane, phosgene, CO, $CO_2$, HCl, Cl$_2$.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1183-1188
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• 1998

This study was carried out to elucidate the immunomodulating activity of protein bound polysac charide extracted from Ganoderma lucidum(PSG). Macrophage drived reactive radicals were known as an effector for antimicrobial and anticancer functions. The promising immune response molecule, reactive oxygen intermediates(ROIs), was determined in TIB 71 cells with PSG at various experimental conditions. Treatment with 0.5mg PSG significantly increased the production of ROIs, superoxide anion as well as hydrogen peroxide, from TIB 71 cells(p<0.001). Under the same concentration, con siderable results were obtained from 24 hour cultivation with 106 cells at 5% CO2 incubator. The cells were trigged with PMA(5.3 M) after primed BCG(100 M) or IFN (100U) alone could not induce the production of ROIs, but it had a significant potentiating effect on ROIs secretion when the cells were treated with PSG.

• 품질경영학회지
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• 제31권2호
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• pp.51-68
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• 2003

This research addresses familiarity and degree of using Internet site and trust building to affect service quality in e-commerce. We assume that the familiarity and frequency of using Internet site affect perceived service quality of customer. Also it assumes that customer's trust building intermediates their relationships. Several hypotheses are set to test these assumptions empirically. Consequently, the results show that familiarity of using Internet site affects customer's perceived service quality significantly except for tangible. Also it is found that degree of customer's trust building intermediates the relationship between familiarity of using Internet site and customer's perceived service quality significantly. For gaining good trust of customer in Internet site, we suggest that familiarity should fit into customer's needs.

• Journal of Photoscience
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• 제10권1호
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• pp.165-173
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• 2003

m-Phenylene-linked biscarbenes, bisnitrenes and carbenonitrenes can be formed photochemically from appropriate nitrogenous precursors. Generation of such reactive intermediates under matrix-isolation conditions allows for their characterization by spectroscopic techniques such as ESR, UV /vis and IR. The latter method is also useful in characterizing secondary products derived from these reactive intermediates. Computational chemistry methods complement experimental IR data, aiding, thus, in identification of such compounds. In addition electronic structure calculations help in developing qualitative and semi-quantitative models, which can be useful in predicting ground-state multiplicities. The parent systems of m-phenylene-linked carbenes and nitrenes have high-spin ground states, but a switching to lower multiplicity can be achieved by chemical substitution. The ground state and various low-lying excited states of m-phenylenecarbenonitrenes can be reasonably approximated by simple valence-bond depictions. Finally, m-phenylenecarbenonitrenes are photoreactive in the inert matrix isomerizing to cyclopropene derivatives.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.719-722
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• 1998

The addition of decane to biotransfonnation media containing Yarrowia lipolytica led to the accumulation of intennediate L-phenylacetaldehyde and L-phenethyl acetate during bioconversion of L-phenylalanine, whilst none of these products were obtained in conventional aqueous fennentations. The results obtained support an earlier hypothesis (Spinnler et al. 1996. Proc. Natl. A cad. Sci. USA 93: 3373-3376) that organic solvents, acting as "thermodynamic traps" for hydrophobic intermediates, can substantially alter metabolic fluxes.

• 한국토양환경학회지
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• 제3권3호
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• pp.87-92
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• 1998

The effect of chemically oxidized intermediates of Polynuclear Aromatic Hydrocarbon (PAH) compounds on the degradation of the parent PAHs was characterized and evaluated for the context of cooxidation. Anthracene and pyrene exhibited extensive degradation (mean percent removal of 57.5%) after 28 days of incubation by introducing the Fenton oxidation intermediate of the PAH compounds, while unoxidized anthracene and pyrene exhibited 12.5% removal The chemical oxidation products can serve as a structually similar analogue substrates for a consortia of soil microorganisms and as a metabolic intermediates in the biodegradation sequence of the parent PAH compounds. These results may be interpreted in the context of cooxidation mechanism whereby high recalcitrant PAH compounds are biodegraded in the soil and suggest a potential tool for bioremediation of PAHs contaminated soils and protection of groundwater.

• 한국환경과학회지
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• 제22권9호
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• pp.1089-1095
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• 2013

The degradation of 3-chlorophenol(3-CP) by various AOPs(Advanced Oxidation Processes) including the ultraviolet / hydrogen peroxide, the Fenton and the ultraviolet(UV)-Fenton process has been conducted. The highest removal efficiency for 3-CP in the aqueous phase was obtained by the UV-Fenton process among the AOPs. In the UV-Fenton process, The removal efficiency of 3-CP decreased with increasing pH in the range of 3 to 6, and it decreased with increasing initial concentration. As the intermediates of 3-CP by UV-Fenton reaction, 3-chlorocatechol, 4-chlorocatechol, and chlorohydroquinone were detected thus the degradation pathways were proposed.

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4309-4315
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• 2011

For synthesis of benzastatin E, F and G analogues, the indole-2-carbaldehydes with or without substituents at C-5 position were prepared as key intermediates. Several synthetic attempts to achieve benzastatin E-G analogues were suggested using the indole-2-carbaldehyde intermediates.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2459-2466
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• 2010

Unfunctionalized biaryl compounds were parallelly and combinatorially prepared by the traceless hydrogenolysis of biarylsulfonates supported on pentaerythritol. The hydrogenolysis using 2-propylmagnesium chloride in the presence of $dppfNiCl_2$ efficiently generated corresponding biaryl derivatives without any memory of the support. The strategy using pentaerythritol as a small soluble support was disclosed to have a potential to combine the benefits of both SPOS and solution-phase reaction with fast reaction rate, facile isolation of intermediates, easy analysis of intermediates and atom economical manner. The novel tetrapodal support is expected to be an efficient substitute for polymeric supports in many circumstances.

• 한국식품과학회지
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• 제25권5호
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• pp.521-525
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• 1993

계면에서의 단백질 흡착 기작을 연구하기 위하여 여러 단백질의 A/W 계면에서의 흡착이 조사되었다. BSA intermediates들의 흡착결과는 단백질 2차, 3차 구조가 계면에서의 흡착기작에 영향끼친 것을 나타냈으며, succinylated ${\beta}-lactoglobulin$의 흡착에서는 순 음전하의 증가가 정전기적 상호작용에 영향끼침을 보여 주었다. 또한 ${\beta}-casein$의 흡착은 물 구조를 파괴하는 chaotropic 염 존재하에서 흡착속도가 떨어지는 것을 시사했다.