• 제목/요약/키워드: Microporous

검색결과 258건 처리시간 0.024초

상분리법에 의한 다공질유리의 제조 및 탈염특성 (Preparation of Microporous Glasses by the Phase-Separation Technique and Their Salt-Rejection Characteristics)

  • 현상훈;김계태
    • 한국세라믹학회지
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    • 제23권5호
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    • pp.93-101
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    • 1986
  • Microporous glasses were prepared from the 50 $SiO_2-44$ $B_2O_3-6$ $Na_2O$(wt%) parent glass by the phase eparation technique and were characterized by SEM, BET, and Gas Adsorption methods to investigate the possiblity of their use as salt-rejection membranes for reverse osmosis. The conditions of the phase separation for the possible glass membranes were optimized for the given parent glass. The temperature and duration of heat-treatment were desired to be lower(853K) and shorter (1/2~1 hr) respectively. The specific surface areas of porous glasses prepared in this study were about 80~120$m^2$/g and their pore size distribution had a unimodal shape(peak pore radius less than 15$\AA$) It was suggested that the porous glass obtained in this work could be effective for salt-rejection in point of pore size distributions but the way to increase its surface area for the high flux must be studied.

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고분자 연료전지의 다공성층 내에서의 액상수분 이동에 관한 공극-네트워크 해석 연구 (Pore-network Study of Liquid Water Transport through Multiple Gas Diffusion Medium in PEMFCs)

  • 강정호;이상건;남진현;김찬중
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2011년 춘계학술대회논문집
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    • pp.46-53
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    • 2011
  • Water is continuously produced in polymer electrolyte membrane fuel cell (PEMFC), and is transported and exhausted through polymer electrolyte membrane (PEM), catalyst layer (CL), microporous layer (MPL), and gas diffusion layer (GDL). The low operation temperatures of PEMFC lead to the condensation of water, and the condensed water hinders the transport of reactants in porous layers (MPL and GDL). Thus, water flooding is currently one of hot issues that should be solved to achieve higher performance of PEMFC. This research aims to study liquid water transport in porous layers of PEMFC by using pore-network model, while the microscale pore structure and hydrophilic/hydrophobic surface properties of GDL and MPL were fully considered.

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A New Nanohybrid Photocatalyst between Anatase (TiO2) and Layered Titanate

  • Lee, Hyun-Cheol;Jeong, Hyun;Oh, Jae-Min;Choy, Jin-Ho
    • Bulletin of the Korean Chemical Society
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    • 제23권3호
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    • pp.477-480
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    • 2002
  • A new microporous TiO2-pillared layered titanate has been successfully prepared by hybridizing the exfoliated titanate with the anatase TiO2 nano-sol. According to the X-ray diffraction analysis and N2 adsorption-desorption isotherms, the TiO2-pillared layered titanate showed a pillar height of ~2 nm with a high surface area of ~460 m2/g and a pore size of ~0.95 nm, indicating that a microporous pillar structure is formed. Its photocatalytic activity was evaluated by measuring the photodegradation rate of 4-chlorophenol during irradiation of catalyst suspensions in an aqueous solution. An enhancement in activity of ca. 170% was obtained for TiO2-pillared layered titanate compared to that of the pristine compound such as layered cesium titanate.

MPCE copolymer와 습식 폴리우레탄의 블렌드에 의한 투습방수 나일론 직물의 제반 물성변화에 관한 연구 (Property Evaluation of Breathable Blend Fabric of MPCE Copolymer and Wet Coagulated Polyurethane)

  • 이종우;채애정;배진석
    • 한국염색가공학회지
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    • 제26권4호
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    • pp.322-330
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    • 2014
  • The phospholipid-based MPCE(2-Methacryloxyethyl Phosphoryl Chlorine) copolymer was mixed with wet polyurethane for coating of nylon fabrics. The substitution rate of water in coagulation bath with DMF was changed under control of the size of formed hydrophilic microporous cell enable to manufacture excellent breathable, anti-bacterial and moisture control fabrics. Biocompatible property, vapor permeability, hydrostatic pressure, moisture management and anti-bacterial property were investigated for treated nylon fabrics. In result, increased moisture transmission rates, decreased water resistance and outstanding moisture control property could be confirmed by enhanced hydrophilicity of wet-coated nylon fabric with MPCE copolymer.

비분산 막-용매추출에 의한 유기오염물의 분리 (Separation of Organic Pollutants by Nondispersive Membrane-Solvent Extraction)

  • 유홍진;한성록
    • 한국산학기술학회논문지
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    • 제5권2호
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    • pp.174-185
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    • 2004
  • 미세기공 중공사형 모듈을 이용한 비분산 막-용매 추출에 의하여 유기오염물을 페수로부터 분리하였다. 시스템은 향류 및 병류로 각각 진행되었으며, 분배계수의 비교로부터 MIBK가 분리용 용매로 선정되었다. 향류의 분리도가 병류보다 우수하였으며, 총괄물질전달계수도 구하였다.

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第二減速 乾燥期에 있어서의 假濕球溫度의 普偏性 (The Universality of the Pseudo Wet Bulb Temperature During the Second Falling Rate Period)

  • 박성신
    • 대한화학회지
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    • 제16권2호
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    • pp.106-116
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    • 1972
  • 물 및 Methyl Alcohol 과 같은 液體에 젖은 巨大孔 不活性 微少孔 不活性 및 微小孔 濕潤性 物質을 乾燥할때 假濕球 溫度가 普扁的으로 形成되며 假濕球 溫度는 空氣乾操의 第 2 減速期中 乾球溫度와 濕球溫道間에 나타난 하나의 새로운 一定溫道이다. 이 溫度는 液體 空氣 境界에서의 熱傳達, 蒸氣壙散, 液體蒸發 現象을 考慮한 式으로 計算되며 Nissan Bolles 및 George가 誘導한 式에 依하여 計算된 數値는 實險結果値와 一致한다.

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