• 제목/요약/키워드: material transport

검색결과 1,165건 처리시간 0.029초

Multicomponent Nanostructured Materials for Separation Membranes

  • Peinemann, Klaus-Viktor
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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    • pp.11-11
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    • 2004
  • Under the coordination of GKSS a new European project in the field of membrane development started recently. This project focuses on the development of novel nanostructured materials for selective material transport and separation. Two classes of materials will be developed in this project: nanostructured organic/inorganic hybrid materials and functional self-organized supramolecular copolymers.(omitted)

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연안에서의 질량운반에 관한 기초적 연구 (A Fundamental Study on Material Transport in the Littoral)

  • 유경환
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 1980년도 제22회 수공학 연구발표회 논문초록집
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    • pp.25-26
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    • 1980
  • 유사량 조사는 최초로 17세기 초에 이태리에서 실시하였으나 기본 이념이 과학적으로 실시되기는 18세기에 이르러 불란서에서 양적인 유사량을 측정한 것이 처음이었다. 최근에 와서 Linsley(1958)는 상류에서 하류로 유하되는 유사의 60~65%가 하천에서 침전되고 나머지는 유하된다고 하였다.

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Evaluation of Water Retentive Pavement as Mitigation Strategy for Urban Heat Island Using Computational Fluid Dynamics

  • Cortes, Aiza;Shimadera, Hikari;Matsuo, Tomohito;Kondo, Akira
    • Asian Journal of Atmospheric Environment
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    • 제10권4호
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    • pp.179-189
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    • 2016
  • Here we evaluated the effect of using water retentive pavement or WRP made from fly ash as material for main street in a real city block. We coupled computational fluid dynamics and pavement transport (CFD-PT) model to examine energy balance in the building canopies and ground surface. Two cases of 24 h unsteady analysis were simulated: case 1 where asphalt was used as the pavement material of all ground surfaces and case 2 where WRP was used as main street material. We aim to (1) predict diurnal variation in air temperature, wind speed, ground surface temperature and water content; and (2) compare ground surface energy fluxes. Using the coupled CFD-PT model it was proven that WRP as pavement material for main street can cause a decrease in ground surface temperature. The most significant decrease occurred at 1200 JST when solar radiation was most intense, surface temperature decreased by $13.8^{\circ}C$. This surface temperature decrease also led to cooling of air temperature at 1.5 m above street surface. During this time, air temperature in case 2 decreased by $0.28^{\circ}C$. As the radiation weakens from 1600 JST to 2000 JST, evaporative cooling had also been minimal. Shadow effect, higher albedo and lower thermal conductivity of WRP also contributed to surface temperature decrease. The cooling of ground surface eventually led to air temperature decrease. The degree of air temperature decrease was proportional to the surface temperature decrease. In terms of energy balance, WRP caused a maximum increase in latent heat flux by up to $255W/m^2$ and a decrease in sensible heat flux by up to $465W/m^2$.

Binaphthyl group 기반의 물질을 이용한 효율적인 White OLED 소자에 대한 연구 (Study on the Efficient White Organic Light-Emitting Diodes using the Material of Binaphthyl Group)

  • 여현기
    • 한국응용과학기술학회지
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    • 제29권3호
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    • pp.459-465
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    • 2012
  • 본 연구에서 7,7'-(2,2'dimethoxy-1,1'-binaphthyl-3,3'-diyl) bis(4-(thiophen-2-yl) benzo[e] [1,2,5] thiadiazole (TBT) 라는 binaphthyl기를 기반으로 가지는 녹색 도판트 물질을 합성하였다. 추가적으로 인광 발광 물질인 iridium(III)bis[(4,6-di-fluoropheny)-pyridinato -N,C2]picolinate (FIrpic)을 홀 수송용 호스트 물질인 N,N'-dicarbazolyl-3,5-benzene (mCP)에 도핑하고, TBT와 bis(2-phenylquinolinato)-acetylacetonate iridium(III) (Ir(pq)2acac)를 전자 수송용 호스트 물질인 1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBi)에 도핑하여 백색 빛을 발광하는 white organic light emitting diode (OLED)를 제작하였다. TBT를 사용하여 제작한 white OLED의 최대발광 효율과 외부 양자 효율은 각각 5.94 cd/A 과 3.23%를 나타냄을 알 수 있었다. Commission Internationale de I'Eclairage (CIE) 색 좌표의 값은 1000 nit에서 (0.34, 0.36)을 띄면서 순백색을 구현함을 확인하였다.

GIS 공간 분석기법을 통한 철도사고위험물질별 피해규모 자동추출방안 (A Method to Measure Damage Areas by the types of Railroad Hazardous Material through GIS Spatial Analysis)

  • 김상균;김시곤;이원태
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.1769-1778
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    • 2009
  • 산업의 발달 및 도시화의 증가로 인해 위험물질을 포함한 물류 수송량은 날로 증가하는 추세이고 위험물질 수송차량들의 사고발생 위험도 따라서 증대되고 있다. 본 연구에서는 위험물 운송이 점차 증가하고 있는 철도수송에 있어 기존 선행 연구의 피해규모 분석모형을 적용하고, 위험물 물류 표준화 연구에서 정의된 물질별 사고노출량을 기준으로 하여 위험물 물질별 인구 및 환경 노출규모를 GIS(Geographic Information System)의 버퍼링 분석 기 법을 통하여 일반적으로 분석이 어려운 피해규모산정을 자동으로 도출하는 방안을 제시하였다. 각 링크별 인구 및 노출규모 산출 모형을 적용하기 위해서는 Network(철도망), Zone(행정구역), 철도사고 Data, 철도화물 통행량, 하천 및 강 등을 GIS Database로 구축하였고, 최종적으로 Buffering 분석과 함께, 중첩분석의 Clip 기법과 Special Join 기법을 함께 사용하여 본연구의 제시한 위험물 물질별 피해규모 자동 추출 방안을 제시해 보았다.

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PECCP LB 박막을 발광층으로 사용한 유기 발광 다이오드의 특성 (Characteristics of Organic Light-Emitting Diodes using PECCP Langmuir-Blodgett(LB) Film as an Emissive Layer)

  • Lee, Ho-Sik;Lee, Won-Jae;Park, Jong-Wook;Kim, Tae-Wan;Dou--Yol Kang
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.111-114
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    • 1999
  • Electroluminescence(EL) devices based on organic thin films have been attracted lots of interests in large-area light-emitting display. In this stuffy, an emissive layer was fabricated using Langmuir-Blodgett(LB) technique in organic light-emitting (OLEDs). This emissive organic material was synthesized and named PECCP[poly(3.6-N-2-ethylhexyl carbazolyl cyanoterephthalidene)] which has a strong electron donor group and an electron acceptor group in main chain repeated unit. This material has good solubility in common organic solvents such as chloroform. THF, etc, and has a good stability in air. The Langmuir-Blodgett(LB) technique has the advantage of precise control of the thickness down to the molecular scale, In particular, by varying the film thickness it is possible to investigate the metal/polymer interface. Optimum conditions for the LB film deposition are usually determined by investigating a relationship between a surface pressure $\pi$ and an effective are A occupied by one molecule on the subphase. The LB films were deposited on an indium-tin-oxide(ITO) glass at a surface pressure of 10 mN/m and dipping speed of 12 mm/min after spreading PECCP solution on distilled water surphase at room temperature, Cell structure was ITO/PECCP LB film/Alq$_3$/Al. We considered PECCP as a hole -transport layer inserted between the emissive layer and ITO. We also used Alq$_3$ as an emissive layer and an electron transport layer. We measured current-voltage(I-V) characteristics, UV/visible absorption, PL spectrum and EL spectrum of the OLEDs.

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정공 주입층 CuPc 두께 변화에 따른 유기 발광 소자의 발광 특성 (Electroluminescent Properties of Organic Light-emitting Diodes Depending on the Thickness of CuPc Hole-injection Layer)

  • 이정복;김경환;김태완;이원재
    • 한국전기전자재료학회논문지
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    • 제26권12호
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    • pp.899-903
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    • 2013
  • We investigated the luminescence properties of $Alq_3$ in the device structure of ITO/CuPc/TPD/$Alq_3$/Al. The CuPc as a hole-injection material and TPD as hole-transport material. Emission properties were measured by varying a layer thickness of CuPc (0 nm to 50 nm), which is the hole-injection layer. As a result, it was found that the hole injection occurs smoothly when the layer thickness was 20 nm among the thicknesses from 0 nm to 50 nm.