• 제목/요약/키워드: 김남석

검색결과 158건 처리시간 0.024초

지방산과 인지질(DOPC)의 혼합 LB막의 광이성질화 현상에 관한 연구 (Photoisomerization of Mixture LB Films of Fatty Acid and Phospholipid(DOPC))

  • 박근호;심경재;김남석
    • 한국응용과학기술학회지
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    • 제19권1호
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    • pp.43-48
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    • 2002
  • We carried out this subject to observe photoisomerization using 1,2-dioleoyl-sn- glycero-3-phosphocholine(DOPC) mixed with fatty acid containing azobenzene group which has reversible to cis-trans by light irradiation. Spreading solutions for the LB films were prepared in chloroform($5.0{\times}10^{-5}$mol/L).We investigated the photoisomerization and property of the organic ultra thin film of fatty acid containing azobenzene was prepared on the hydrophilic ITO(idium tin oxide) glass plate by LB method. As a result, the absorption spectra of 8A5H and DOPC of mixture LB films was induced to photoisomerization by alternating irradiation of ultraviolet and visible light, because the condensation of pure azobenzene monolayers was loosened by the introduction of phospholipid into the monolayers, and the molecular high aggregation in pure azobenzene monolayers is also weakened by the introduction of phospholipid. We found that it was reversibly induced to cis-trans photoisomerization in several solvents and mixture LB films.

무기/유기 Core-Shell 에멀젼 고분자의 합성 (Synthesis of Inorganic/Organic Core-Shell Polymer)

  • 김남석;김덕술;박근호
    • 한국응용과학기술학회지
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    • 제19권4호
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    • pp.265-272
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    • 2002
  • $CaCO_{3}$ absorbed sodium lauryl sulfate (SLS) surfactant was prepared, Core-shell polymers of inorganic/organic pair, which have both core and shell component, were synthesized by sequential emulsion polymerization using styrene(St) as a shell monomer and potasium persulfate (KPS) as an initiator, We found that when $CaCO_{3}$; core prepared by adding 2,0 wt% SLS, $CaCO_{3}$ core/PSt shell polymerization was carried out on the surface of $CaCO_{3}$ particle without forming the new PSt particle during St shell polymerization in the inorganic/organic core-shell polymer preparation, The structure of core-shell polymer were investigated by measuring the degree of decomposition of $CaCO_{3}$ using HCl solution, thermal decomposition of polymer composite using thermogravimetric analyzer and morphology by scanning electron microscope.

축소 모형 실험을 통한 정거장내 적정 배연방식에 관한 연구 (Experimental Investigation about Optimum Smoke Extraction System for Underground Station)

  • 이호근;김명우;이필영;김남석
    • 한국방재학회 논문집
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    • 제8권4호
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    • pp.53-59
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    • 2008
  • 지하철터널에서 화재가 발생하면, 열차는 가장 가까운 정거장으로 대피하여 승객들을 하차시켜야 한다. 실제로 대구지하철 화재사고가 이러한 방식으로 대응 하였으나 큰 인명 피해를 초래하였다. 지하철 정거장의 화재배연시스템은 열차화재에 대응할 수 있도록 설계되어 있지 않기 때문에 화재열차의 정거장 진입시 예상치 못한 피해를 유발할 수 있으며 피해방지를 위한 정거장 선로부의 배연계획 수립이 필요하다. 본 연구의 목적은 정거장 선로부의 열차화재시 효율적인 배연방식을 연구하고 승객의 피난 동선 확보를 위해 상층부로의 역류 방지대책을 축소모형실험에 의하여 수립하는 것이다.

국가문헌의 수집과 보존 (The collection and preservation of national literature)

  • 김남석
    • 한국도서관정보학회지
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    • 제15권
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    • pp.79-111
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    • 1988
  • The purpose of this study has its meaning to indicate the direction on collection and preservation of national literature which is one of the must important functions of the Central National Library. The Central National Library is, however, a representative library of our country and collect every kind of literature and to meet the requests of its users, the present situation of The Central National Library can't be performed sufficiently on these actions. According to studies of this paper, it have suggested the following five methods as a method of collecting national literature. First, the method by registering copyright endowing the number of copyright like ISBN. Second, the method a n.0, pplied by revising and su n.0, pplementing present legal deposit system. Thirdly, the method that the central one institution secure national budget collect literature of nation i.e., central intensive collection one. Fouthly , method of collecting literature by partial charge through local library networks. Fifthly, method by subject intensive collecting. As the preserving method of national literature, this research has indicated the following two ways. First, to keep the literatures forever, the method of The Central National Library keeps records as a limited volume. Second, The method of dispersing records as the local libraries. To put these methods into practice, it must be preceded that not only national helps, budget secures are needed but special committee must be organized to keep and preserve national literatures and material range also be extended and bibliographies for information data issuing must be worked out.

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쉘형 스페이스 프레임 구조물의 하중 및 경계조건에 따른 불안정 거동에 관한 연구 (A Study on the Unstable behavior according to Lode and boundary condition of shelled space frame structure)

  • 김남석;손수덕;김승덕
    • 한국공간구조학회:학술대회논문집
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    • 한국공간구조학회 2008년도 춘계 학술발표회 논문집
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    • pp.80-85
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    • 2008
  • 본 논문에서는 쉘형 스페이스 프레임 구조물의 구조 불안정 특성을 조사한다. 대공간 구조물은 대경간을 가볍게 만들기 위해 두께비를 얇게 만들어야 하므로, 구조설계시 구조불안정 검토가 중요하다. 쉘형 구조물의 구조불안정은 다양한 조건에 따라 민감하게 반응하며, 이는 대변형을 수반하는 비선형 문제에 귀착하게 된다. 따라서 본 연구에서는 기하학적 비선형을 고려한 수치해석 기법을 통하여 쉘형 스페이스 프레임 구조물의 하중 및 경계조건에 따른 불안정 거동을 비교하고, 불안정 현상에 미치는 영향을 파악하여 기초적인 붕괴 메커니즘을 규명한다.

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산 에칭에 의한 BaO-B2O3-ZnO계 유리조성물의 용출 현상 (Dissolution Phenomenon in BaO-B2O3-ZnO Glass System by Acid Etching)

  • 김재명;홍경준;김남석;김형순
    • 한국세라믹학회지
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    • 제43권1호
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    • pp.33-37
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    • 2006
  • For producing the fine ribs structure of plasma display panel, the metal ions of barrier materials during the etching process should be understood on the etching mechanism with etching conditions. Etching was done on bulk glasses of the $BaO_B_2O_3-ZnO$ system with $HNO_3$ solution at $40^{\circ}C$. The surface structure of glasses and ion dissolution were analyzed by ICP (Inductive Coupled Plasma measurement). The structure and surface of the etched bulk glass were investigated by using scanning electron microscopy and nanoindenter. As a result, Ba (3-35 ppm/min) and Zn (2-27 ppm/min) ions as major components were leached in the solution and the leached layers were found to be phosphor-rich surface layers. A decrease of the bridge oxygen and relative increase of non bridge oxygen in the etched glass were found by X-ray photoelectron spectroscopy.

인지질(DOPC)과 지방산(8A5H)의 혼합 LB막의 광이성질화 현상과 전기화학적 특성 (Electrochemical Properties and Photoisomerization of DOPC-8A5H Mixture Langmuir-Blogett Films)

  • 박근호;최성현;김남석;김덕술
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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    • pp.874-877
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    • 2004
  • We carried out this subject to observe electrochemical properties of 1,2-dioleoyl-sn- glycero-3-phosphocholine(DOPC) mixed with fatty acid containing azobenzene group by using cyclic voltammetry with a three-electrode system, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode in $NaClO_4$ solution. We investigated the photoisomerization and electrochemical property of the organic ultra thin film of fatty acid containing azobenzene was prepared on the hydrophilic ITO(idium tin oxide) glass plate by LB method. As a result, the absorption spectra of BASH and DOPC of mixture LB films was induced to photoisomerization by alternating irradiation of ultraviolet and visible light. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650 mV and measured to the initial point. The scan rate were 50, 100, 150 and 200 mV/s. As a results, LB films of BASH-DMPC appeared reversible process caused by the reduction-oxidation current from the cyclic voltammogram.

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접선 강성방정식과 비선형 강성방정식을 이용한 비선형 해의 정확성 비교에 관한 연구 (A study on the Accurate Comparison of Nonlinear Solution Which Used Tangent Stiffness Equation and Nonlinear Stiffness Equation)

  • 김승덕;김남석
    • 한국공간구조학회논문집
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    • 제10권2호
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    • pp.95-103
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    • 2010
  • 본 논문에서는 비선형 강성방정식의 정확성 향상에 관해 연구한다. 대공간 구조물은 대경간을 가볍게 만들기 위해 두께비를 얇게 만들어야 하므로, 구조설계시 구조불안정 검토가 중요하다. 쉘형 구조물의 구조불안정은 초기 조건에 매우 민감하게 반응하며, 이는 대변형을 수반하는 비선형 문제에 귀착하게 된다. 따라서 구조불안정을 정확히 알아보기 위해 비선형 강성방정식의 정확성이 향상 되어야 한다. 본 연구에서는 스페이스 트러스를 해석 모델로 하며 접선 강성방정식과 비선형 강성방정식의 두 이론을 프로그램으로 작성하여 비선형 해석을 수행한다. 두 이론의 해석 결과를 비교 고찰하여 비선형 강성방정식의 정확성 및 수렴성 향상에 대해 검토 한다.

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수중에서의 인체에 가해지는 전기적 현상에 관한 연구 (A Study on the Human body Model shocked Electric installation in Underwater)

  • 우정현;박하용;송우창;김남석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 제39회 하계학술대회
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    • pp.1338-1339
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    • 2008
  • In this paper, charging part by basic from Andrew's body model research to second a danger have affect on remaining and rehabilitation humans in space under water. The construction of a circuit make to Andrew's body model. It compare that voltages measure a hand, a breast, a groin and electric currents measure an arm, a breast, a leg with safety a limit of body through an electric current. Out of result, it research that magnitude and wave of body passing an electric current give the effect to the heart control a signal and it have affect on direct the ventricle of the heart in detail motion. A thing of this sort get through to the simulation by the ATP-Draw program. The results from above, it is publish one's research work with safety a limit electric angle take measurement of resistance a body in under water and to the voltage and electric current passing each parts.

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고분자물질 바닥재의 열적특성에 관한 연구 (A Study on Thermal Characteristics on Polymeric Floorings)

  • 이내우;김남석;문병수
    • 한국안전학회지
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    • 제21권6호
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    • pp.38-45
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    • 2006
  • Polymeric floorings mainly consisted of PVC are easily decomposed by many kinds of hot environmental factors, then generate hazardous asphyxiate gases and/or toxic gases etc. Therefore the mechanism of decomposition and quantitative toxic indices of products are very important for preventing safety and health disasters, especially in case of confined area. So we have investigated decomposition kinetics, numbers of process involved, toxicity indices of product and so on, using DSC, TGA, FT-IR and Pyrolyzer-GC/MS. The thermal decomposition process of polymeric floorings can be mainly divided by dehydrochlorinated reaction and polyene decomposition step, and activation energies of those are approximately $53.93{\sim}62.42kcal/mol$. Especially lethal concentration($LC_{50}$), fractional effective dose (FED) are calculated by measuring the amount of decomposition product. The values on $LC_{50}$ of sample G are ranged $2,003{\sim}2,019(mg/m^{3})$ in case of sample K and H are $1,877,\;1,998(g/m^{3})$ respectively. Even if the results are estimated by calculation method without animal test and/or clinical demonstration, these values could be very useful data for occupational health, hygiene and safety control.