• Title/Summary/Keyword: 의존성 구조

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The Cytotoxicity of 1,3-diphenylpropenone derivatives (1,3-diphenylpropenone 유도체의 세포독성)

  • Yu, Seong-Jae;Kwon, Byung-Mok;Lee, Chong-Ock;Choi, Sang-Un;Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.42 no.1
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    • pp.68-72
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    • 1999
  • The cytotoxicity of 1,3-diphenylpropenone derivatives known to inhibit the farnesyl protein transferase (FPTase) was examined against various established tumor cell line, A549 (lung cancer), SKMEL-2 (uterine cancer), HCT-15 (skin cancer), SKOV-3 (brain cancer) and XF-498 (colon cancer) of the 1,3-diphenylpropenone derivatives showing farnesyl protein transferase (FPTase) inhibition activity. And the structure-activity relationship (SAR) between structure of 1,3-diphenylpropenone derivatives as substrate and cytotoxicity was investigated by Free-Wilson analysis as well as Hansch method with tumor cell lines. From the result of Free-Wilson analyses, X-substituents on the benzoyl group have a more important role than Y-substituents on the styryl group. The 2,4-dichloro substituent, 15 and 2,4-dimethyl substituent, 16 showed the highest cytotoxicity (average pI_(50)=5.0). Particulary, the cytotoxicity of X-substituents increased with electronic effect $({\sigma})$ due to weak electron withdrawing group with optimum value $({\sigma}_{opt}=0.22{\sim}0.29})$ whereas that of Y-substituent resulted from various factors such as logP, $B_1$ and R constant.

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Activity Comparison According to Prepared Method of Cu-Mn Oxide Catalyst for Toluene Combustion (톨루엔 분해를 위한 구리-망간 산화물 촉매의 제조방법에 따른 활성 비교)

  • Kim, Hye-Jin;Choi, Sung-Woo;Lee, Chang-Seop
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.3
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    • pp.249-256
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    • 2006
  • Catalytic combustion of toluene was investigated on the Cu-Mn oxide catalysts prepared by the impregnation(Imp) and the deposition-precipitation(DP) methods. The mixing of copper and manganese has been found to enhance the activity of catalysts. It is then found that catalytic efficiency of the Cu-Mn oxide catalyst prepared by the DP method on combustion of toluene is much higher than that of the Cu-Mn oxide catalyst prepared by Imp method with the same chemical composition. The catalyst prepared by the deposition-precipitation method observed no change of toluene conversion at time on stream during 10 days and at the addition of water vapor. On the basis of catalyst characterization data, it has been suggested that the catalysts prepared by the DP method showed uniform distribution and smaller particle size on the surface of catalyst and then enhanced reduction capability of catalysts. Therefore, we think that the DP method leads on progressive capacity of catalyst and promotes stability of catalyst. It was also presumed that catalytic conversion of toluene on the Cu-Mn oxide catalyst depends on redox reaction and $Cu_{1.5}Mn_{1.5}O_4$ spinel phase acts as the major active sites of catalyst.

Contact fatigue and strength degradation in dental ceramics (치아용 세라믹스에서의 접촉피로 및 강도저하)

  • 정연길;이수영;최성철
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.9 no.5
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    • pp.527-533
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    • 1999
  • Hertzian indentation tests with spherical indenters in water were conducted to examine the contact fatigue in three dental ceramics, such as feldspathic porcelain, micaceous glass-ceramic (MGC) and glass-infiltrated alumina, which was used as dental restorations, and evaluated the effect of contact damage on strength. Initial damage was dependent of microstructure, showing cone cracks of brittle behavior in the feldspathic porcelain and deformation of quasi-plastic behavior in the MGC, with an intermediate case in the glass-infiltrated alumina. However, as increasing the number of cyclic loading (n=1~n =$10^6$)all materials showed an abrupt strength degradation, at which fracture was originated from damage in the contact fatigue. There were two strength degradation with increasing the number of cyclic loading in specific loads (200N, 500N, 1000N):first was from the cone cracks, and second was from the radial cracks created by cyclic loading. The radial cracks, once formed, led to rapid degradation in strength properties, Finally the material was failed at the high number of cyclic loading. Strength degradation with indentation load at fixed number of cyclic loading indicated that the feldspathic porcelain should be highly damage tolerant to the contact fatigue.

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Study on Temperature Dependence of Molecular Structure in Stearic Acid LB Films Using FTIR-RAS (FTIR-RA 분광법을 이용한 스테아르산 단분자막에서 분자구조의 온도의존성 고찰)

  • Kim, Dong Won;Park, Sang Rae;Umemura Junjo;Takeda Satoshi;Hasegawa Takeshi;Takenaka Tohru;Lee Hai Won
    • Journal of the Korean Chemical Society
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    • v.37 no.6
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    • pp.570-576
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    • 1993
  • 1-, 3-, 9-, and 21-Monolayer Langmuir-Blodgett(LB) films of stearic acid were deposited on silver-coated glass slides at the surface pressure of 30 mN/m. Fourier transform infrared(FTIR) reflection-absorption spectra (RAS) of these LB films were recorded at various temperatures from 31 to $72^{\circ}C.$ The spectra at $31^{\circ}C$ exhibited characteristic features of highly perpendicular orientation of the hydrocarbon chain. In the 1-monolayer LB film, the C=O stretching band was not observed, presumably due to the image dipole effect on the silver surface. In the 1-and 3-monolayer LB films, the trans isomer of stearic acid was prominent, but the cis isomer was dominant in the 21-monolayer LB film. FTIR-RAS measurements at an elevated temperature indicated that the chain melting temperature increases and approached to the bulk melting point with increasing the number of monolayer, except for the 1-monolayer LB film which has a higher melting temperature than the 3-monolayer film due to the strong interaction with the silver substrate.

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Catalytic Hydrogenation of Unsaturated Organic Compounds by Rutheniumhydridonitrosyl Complexes (Rutheniumhydridonitrosyl 착물을 이용한 불포화 유기화합물의 수소화 반응)

  • Park, Mi Young;Kim, Young Joong;Cho, Ook Jae;Lee, Ik Mo
    • Journal of the Korean Chemical Society
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    • v.40 no.6
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    • pp.445-452
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    • 1996
  • Catalytic hydrogenation of ketones and aldehydes by RuH(NO)$L_3$ ($L_3$: $PPh_3$, PhP($CH_2CH_2PPh_2$)$_2$(etp)) was investigated to examine the reaction mechanism and the competence of hydridonitrosyl complexes as catalysts for organic synthesis. RuH(NO)$L_3$ showed catalytic activity for the hydrogenation and the activities of catalysts were dependent on the steric and electronic factors. The less the steric demands of the substrates become, the more activity the catalysts show. For the electronic effect, the more the partial positive charge on the carbonyl carbon atom in ketones becomes and the more the double bond character of carbonyl group in aldehydes becomes, the more active the catalysts are. These results reflect the difference of reaction mechanisms of two substrates, ketones and aldehydes. Catalytic activities of RuH(NO)(etp) and RuH(NO)($PPh_3$)$_3$ in the presence of extra $PPh_3$ toward hydrogenation showed the existence of a reaction pathway accompanied with the change of the bonding modes of NO ligand. The roles of excess $PPh_3$ change with increase of the mole ratio of $PPh_3$ to catalysts; prevention of ligand dissociation from comlexes → bases → ligands. The activity of RuH(NO)(etp) was lower than that of RuH(NO)($PPh_3$)$_3$ toward the hydrogenation of the same substrates mainly due to the structural difference. These catalysts showed the selectivity toward olefin hydrogenation over carbonyl groups in the competitive reaction.

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Problem Analysis and Improvements Plans for PF ABCP of Apartment Housing Development Projects (공동주택 PF ABCP의 문제점 분석 및 개선방안에 관한 연구)

  • Kim, Soo-Yeol;Hwang, Uk-Sun;Kim, Yong-Su
    • Korean Journal of Construction Engineering and Management
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    • v.12 no.2
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    • pp.133-142
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    • 2011
  • The purpose of this study is to analyze the problems of the parties involved in the issuance of apartment housing development projects. The adapted research method selected four apartment housing development as PF ABCP projects. This study carried out the case about participant institution of PF ABCP funding project including developer, constructor, financial institution so as to draw problems by participant institution. On the basis of the selected case, this thesis proposes methods for involved parties to negotiate and work out problems of the PF ABCP. The results of this study are as follows 1) Launching long-term project financing should be developed, including operating funds and strengthen the ABS and ABCP issuance of credit assessment procedures, combined with the simplicity of the instruments. 2) The Low-risk contract for the construction of simple managerial focus should be the construction, financial institutions essentially dependent on project financing feasibility verification purpose loans to prevent the division a true story, the development should be of interest to be preserved. The proposed included, among other, partial guarantee based on the construction plan financial institutions' share-based investment, and the supplement of legal issues.

DEA Models and Application Procedure for Performance Evaluation on Governmental Funding Projects for IT Small and Medium-sized Enterprises with Exogenously Fixed Variables of Corporate Competency (기업역량을 고려한 외생고정변수를 갖는 IT중소기업 정부자금지원정책 성과평가를 위한 DEA모형 및 활용절차)

  • Park, Sung-Min;Kim, Heon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.5B
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    • pp.364-378
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    • 2008
  • Data Envelopment Analysis(DEA) models can be used for performance evaluation on governmental funding projects for IT small and medium-sized enterprises associated with multiple-outputs/multiple-inputs. In order to enhance the accuracy of DEA efficiency scores, DEA models with exogenously fixed variables are required where the corporate competency is taken into account. Additionally, it is necessary to use multiple DEA basic as well as extended models so as to relax the restriction on the performance evaluation to relying on a single DEA model. In this study; 1)a DEA data structure is designed including exogenously fixed variables representing corporate asset, revenue and the number of employees at the point in time that the governmental funding project concerned is initiated; 2)DEA basic as well as extended models are established according to the DEA data structure presented abovementioned; and 3)a case study is illustrated with an empirical testbed dataset. As for the DEA basic models, CCR, BCC, Super-efficiency model are adopted. The DEA extended models are developed based on the models associated with noncontrollable and nondiscretionary variables. In the case study, it is explained a comparison of DEA models and also major numerical outcomes such as efficiency scores, ranks derived from each DEA model are integrated using Analytic Hierarchy Process(AHP) weights. Performance significance with DEA efficiency scores between technical categories are tested based not only on parametric but also nonparametric single-factor analysis of variance method.

Growth of Thin Film Using Chemical Bath Deposition Method and Their Photoconductive Characteristics (CBD 방법에 의한 CdS 박막의 성장과 광전도 특성)

  • Hong, K.J.;Lee, S.Y.;You, S.H.;Suh, S.S.;Moon, J.D.;Shin, Y.J.;Jeoung, T.S.;Shin, H.K.;Kim, T.S.;Song, J.H.;Rheu, K.S.
    • Journal of Sensor Science and Technology
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    • v.2 no.1
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    • pp.3-10
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    • 1993
  • Polycrystalline CdS thin films were grown on ceramic substrate using a chemical bath deposition method. They were annealed at various temperature and X-ray diffraction patterns were measured by X-ray diffractometer in order to study CdS polycrystal structure. Using extrapolation method of X-ray diffraction patterns for the CdS samples annealed in $N_{2}$ gas at $550^{\circ}C$ it was found hexagonal structure whose lattice constants $a_{o}$ and $c_{o}$ were $4.1364{\AA}$ and $6.7129{\AA}$, respectively. Its grain size was about $0.35{\mu}m$. Hall effect on this sample was measured by Van der Pauw method and studied on carrier density and mobility defending on temperature. From Hall data, the mobility was likely to be decreased by piezo electric scattering at temperature range of 33K and 150k and by polar optical scattering at temperature range of 150K and 293K. We measured also spectral response, sensitivity (${\gamma}$), maximum allowable power dissipation and response time on these samples.

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Characterization of CdSe Thin Film Using Chemical Bath Deposition Method (Chemical Bath Deposition 방법으로 제작한 CdSe 박막의 특성)

  • Hong, K.J.;Lee, S.Y.;You, S.H.;Suh, S.S.;Moon, J.D.;Shin, Y.J.;Jeong, T.S.;Shin, H.K.;Kim, T.S.;Song, J.H.;Rheu, K.S.
    • Journal of Sensor Science and Technology
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    • v.2 no.1
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    • pp.81-86
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    • 1993
  • Polycrystalline CdSe thin films were grown on ceramic substrate using a chemical bath deposition (CBD) method. They were annealed at various temperature and X-ray diffraction patterns were measured by X-ray diffractometer in order to study CdSe polycrystal structure. Using extrapolation method of X-ray diffraction patterns for the CdSe samples annealed in $N_{2}$ gas at $450^{\circ}C$ it was found hexagonal structure whose lattice parameters $a_{o}$ and $c_{o}$ were $4.302{\AA}$ and $7.014{\AA}$, respectively. Its grain size was about $0.3{\mu}m$. Hall effect on this sample was measured by Van der Pauw method and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by piezo electric scattering at temperature range of 33 K and 200 K, and by polar optical scattering at temperature range of 200 K and 293 K. We measured also spectral response, sensitivity (${\gamma}$), maximum allowable power dissipation and response time on these samples.

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Regional Development and the Improvement of Water Quality using Bivalves in Lake Suwa (Japan) (조개를 이용한 일본 수와호의 수질개선과 지역발전의 역사)

  • Okino, Tokio
    • Korean Journal of Ecology and Environment
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    • v.47 no.spc
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    • pp.1-9
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    • 2014
  • Lake Suwa is a natural lake which is well-known for sightseeing and fisheries. It had suffered severe eutrophication during 1960s and 1970s with the occurrence of cyanobacterial blooms and the extinction of some benthic animals. Since 1980 water quality has been improved due to efforts of local government, scientists, and citizens. Of various methods that were attempted to improve the water quality of Lake Suwa biological methods received much attention, because it can improve the lake ecosystem integrity and fisheries in addition to the water quality. The aim of this paper is to introduce the biological methods for water quality improvement that had been employed in Lake Suwa, Japan, and their contribution to the economic benefit of local residents. Until now a significant restoration of water quality has been achieved, but there are insufficient recovery of the sediment and biota due to anoxic hypolimnion of the lake. This study proposed suspended cage culture of bivalves as a feasible method of water quality improvement. Increased grazing by bivalves will contribute to the improvement of water quality and fisheries production, which will contribute both to the ecological restoration and economy of local residents.