• 제목/요약/키워드: membrane property

검색결과 347건 처리시간 0.03초

Removal of Dissolved Oxygen from the Make-up Water of NPP Using Membrane-based Oxygen Removal System

  • Chung, Kun-Ho;Kang, Duck-Won;Hong, Sung-Yull
    • Nuclear Engineering and Technology
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    • 제31권6호
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    • pp.541-547
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    • 1999
  • Corrosion control, in the end-shield cooling system of Wolsung Nuclear Power Plant, is directly related to the control of dissolved oxygen (DO). The current method, being used to deoxygenate the end-shield cooling water, is a chemical treatment by addition of reducing agent, hydrazine, to react with DO. This method has several limitations including high reaction temperature of hydrazine , unwanted explosive hydrogen gas production, and its intrinsic harmful property. A new approach to remove DO using a membrane-based oxygen removal system (MORS) was tried to overcome limitations of the hydrazine treatment. The DO removal efficiency of the MORS was found to be in the range 87% to 98%: The higher vacuum, the lower water flow rate and the higher water temperature tend to increase the DO removal efficiency.

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Prediction of retention of uncharged solutes in nanofiltration by means of molecular descriptors

  • Nowaczyk, Alicja;Nowaczyk, Jacek;Koter, Stanislaw
    • Membrane and Water Treatment
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    • 제1권3호
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    • pp.181-192
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    • 2010
  • A linear quantitative structure-property relationship (QSPR) model is presented for the prediction of rejection in permeation through membrane. The model was produced by using the multiple linear regression (MLR) technique on the database consisting of retention data of 25 pesticides in 4 different membrane separation experiments. Among the 3224 different physicochemical, topological and structural descriptors that were considered as inputs to the model only 50 were selected using several criteria of elimination. The physical meaning of chosen descriptor is discussed in detail. The accuracy of the proposed MLR models is illustrated using the following evaluation techniques: leave-one-out cross validation procedure, leave-many-out cross validation procedure and Y-randomization.

한국산 기름종개속 어류의 난모세포의 부착막 (Adhesive Membrane of Oocyte in Korean Cobitid Species (Pisces, Cobitidae))

  • 김익수;박종영
    • 한국동물학회지
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    • 제38권2호
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    • pp.212-219
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    • 1995
  • Through the histolosical observation of ovary in the nine species of the genus Cobitis, we found that specific adhesive membranes were attached to the outer zone radials during the vitellosenesis. These adhesive membranes could be classified into four forms as follows: 1) granular form of Colitis lutheri, C. striate, and C. sinensis, 2) villous form of C. longicorpus, C. konensis koreensis, C. k. pumilus, and C. granoei, 3) saw-like form of C. rotundicaudata, and 4) filamentous form of C. chou. The various forms of adhesive membrane of egg in the cobitid fishes are showed a species specificitv with reference to their habitats and spawning property.

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스프레이식 고점착 변성 고무 아스팔트 도막 방수재의 재료 및 공법에 관한 실험적 연구 (A Study on the field application analysis for high adhesive spray type of degenerated and rubberized asphalt membrane material)

  • 오상근;송제영;김진성;이남규
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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    • pp.61-65
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    • 2006
  • Urethane, epoxy, acrylic have common property to adhere on the concrete dried surface in the waterproofing materials at present. In the wet condition, however, the materials such as urethane, epoxy, acrylic need a long hardening time and it become a reason of water leakage as the materials breaking down. it is one of the problem to adhere to the substrate. Therefore, in this thesis, I focused to assure the structural safety and durability and quality for waterproofing and safe of construction cost by cut down the cost of labor and reduce the term of works as searching the application of field condition for hish adhesive spray type of degenerated and rubberized asphalt membrane material.

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Effect of Variation of Membrane Thickness on the Activity of $Ca^{2+}$-activated $K^+$ Channel in Planar Lipid Bilayers

  • Seo, Hyoung-Sik;Ryu, Pan-Dong
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1999년도 학술발표회 진행표 및 논문초록
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    • pp.56-56
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    • 1999
  • Change of membrane property can affect the activity of membrane proteins. In this work, we investigated the single channel properties of large conductance $Ca^{2+}$-activated $K^{+}$(BK) channels in planar lipid bilayers of different thickness. First, we recorded the activity of single BK channels from rat skeletal muscle incorporated into the control bilayer, then increased the bilayer thickness by perfusing the recording solution with the one saturated with n-pentane, or reduced the thickness by adding diheptanoylphosphatidylcholine (di$C_{7:0}$PC) to the recording soluton.(omitted)

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열공압 방식의 Polydimethylsiloxane 마이크로 밸브의 제작 및 특성 (Fabrication and Characteristics of Thermopneumatic-Actuated Polydimethylsiloxane Microvalve)

  • 김진호;조주현;한경희;김영호;김한수;김용상
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제53권4호
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    • pp.231-236
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    • 2004
  • A normally open thermopneumaticc-actuated microvalve has been fabricated and their properties are investigated. The advantages of the proposed microvalve are of the low cost fabrication process and the transparent optical property using polydimethylsiloxane (PDMS) and indium tin oxide (ITO) glass. The fabricated microvalves with in-channel configuration are easily integrated with other microfluidic devices on the same substrate. The fabrication process of thermopneumatic-actuated microvalvesusing PDMS is very simple and its performance is very suitable for a disposable lab-on-a-chip. The PDMS membrane deflection increases and the flow rates of the microchannel with microvalvels decrease as the applied power to the ITO heater increases. The powers at flow-off are dependent on the membrane thickness and the applied inlet pressure but are independent of the channel width of microvalves. The flow rate is well controlled by the switching function of ITO heater and the closing/opening times are around 20 sec and 25 sec, respectively.

Moving wall형 LB법에 의하여 제작된 DLPC 지질막의 누적특성 (The Deposition Characterization of DLPC Lipid Membrane Fabricated by Moving wall Type LB Method)

  • 이우선;최창주;정용호;김남오;이경섭;장의구;김태성
    • E2M - 전기 전자와 첨단 소재
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    • 제10권6호
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    • pp.548-554
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    • 1997
  • We fabricated the sample of ultra thin lipid membrane(L-$\alpha$-DLPC) by LB method. The $\pi$-A isotherm of the DLPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. For the good property of lipid monolayer film, it was necessary to prepare at the lower speed of compressing, with an appropriate volume of solutions for spreading. Absorption, transmitance and intensity with the UV spectrophotometer were measured. The Z-type multilayers showed good characteristics better than Y-type. So we found building-up of structurally high quality LB films is essential to study properties of the films and to get reproducible data.

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이차전지용 미세다공성 PVdF 분리막의 제조와 물성 (Preparation and Characterization of Microporous PVdF Membrane for Li-ion Rechargeable Battery)

  • 남상용;유대현;정미애;임지원;변홍식;정철호;이영무;서명수
    • 멤브레인
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    • 제17권3호
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    • pp.233-243
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    • 2007
  • 본 연구에서는 충전용 이차전지의 분리막으로 쓰이는 다공성 막을 기존의 분리막 재료보다 뛰어난 물성을 나타내는 PVdF(poly(vinylidene fluoride))를 사용하여 상전이 방법으로 제조하였다. 용매인 DMF(N,N-dimethylformamide)에 PVdF를 단일상으로 녹인 후 깨끗한 유리판에 캐스팅하여 막을 얻었다. 얻어진 분리막에서 가장 높은 공극률은 78.6%로 얻어졌다. UTM(universal testing machine)을 이용하여 측정된 분리막의 인장강도는 PVdF 20 wt%에서 5.16 MPa의 값을 나타내었다. 시차주사현미경(scanning electron microscopy, SEM)을 이용하여 분리막의 단면 관찰을 통해 다공성을 확인하였다.

지지체 특성이 정삼투막 성능에 미치는 영향 (Effect of Support Membrane Property on Performance of Forward Osmosis Membrane)

  • 정보름;김종학;김범식;박유인;송두현;김인철
    • 멤브레인
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    • 제20권3호
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    • pp.235-240
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    • 2010
  • 본 연구의 목적은 각기 다른 특성을 갖는 지지체에 따른 정삼투막의 성능을 비교 빛 평가하는 것이다. 계변 중합을 통하여 소수성 지지체인 폴리술폰(PSf)과 상대적으로 친수성 지지체인 폴리에테르술폰(PES)의 표변에 폴리아미드 활성층을 갖는 정삼투막을 제조하여 투과유량과 역확산을 비교하였다. PSf 정삼투막과 PES 정삼투막의 투과유량은 $4.36\;L/m^2hr$$17.8\;L/m^2hr$으로 PES를 지지체로 하는 정삼투막이 투과성능이 더 우수함을 알 수 있었으며, 이를 통해 지지체의 친수성과 정삼투 공정에서의 투과성능 간에 관련성이 존재함을 확인할 수 있었다. 또한 막의 두께가 앓아질수록 정삼투 공정에서 막의 투과유량은 증가하였다.