• 제목/요약/키워드: facilitated state

검색결과 83건 처리시간 0.024초

Exploration on new model of selectively preferential sorption-facilitated transport with fixed site carriers

  • Congjie, Gao;Liguang, Wu
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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    • pp.152-154
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    • 2004
  • A new model of selectively preferential sorption-facilitated transport with fixed site carriers was advanced in this paper. A number of experiments were arranged to demonstrate the ideal above. Preliminary results were obtained from the experiments, and shown the model was applicable for many membrane processes, such as RO, ED, gas separation and liquid membranes etc.

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Silver Polymer Electrolyte Membranes for Facilitated Olefin Transport: Carrier Properties, Transport Mechanism and Separation Performance

  • Kim, Jong-Hak;Kang, Yong-Soo
    • Macromolecular Research
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    • 제12권2호
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    • pp.145-155
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    • 2004
  • Facilitated transport membranes for the separation of olefin/paraffin mixtures have long been of interest in separation membrane science because olefins, such as propylene and ethylene, which are important chemicals in petrochemical industries, are currently separated by energy-intensive cryogenic distillation processes. Recently, solid polymer electrolyte membranes containing silver ions have demonstrated remarkable performance in the separation of olefin/paraffin mixtures in the solid state and, thus, they can be considered as alternatives to cryogenic distillation. Here, we review recent progress, and critical issues affecting in the use of facilitated olefin transport membranes; in particular, we provide a general overview with reference to carrier properties, transport mechanisms, and separation performance.

Olefin/Paraffin Separation though Facilitated Transport Membranes in Solid State

  • Hong, Seong-Uk;Won, Jong-Ok;Hong, Jae-Min;Park, Hyun-Chae;Kang, Yong-Soo
    • 한국막학회:학술대회논문집
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    • 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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    • pp.15-18
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    • 1999
  • A simple mathematical model for facilitated mass transport through a fixed site carrier membrane was derived by assuming an instantaneous, microscopic concentration (activity) fluctuation. The current model demonstrates that the facilitation factor depends on the extent of concentration fluctuation, the time scale ratios of diffusion to chemical reaction and the ratio of the carrier concentration to the solute solubility in matrix. The model was examined against the experimental data on oxygen transport in membranes containing metallo-porphyrin carriers, and the agreement was exceptional (within 10% error). The basic concept of this approach was applied to separate olefin from olefin/paraffin mixtures. A proprietaty carrier, developed here, resulted that the selectivity of propylene over propane was more than 120 and the propylene permeance exceed 40 gpu.

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Facilitated Transport of Oxygen in Copolymer Membranes of Styrene and 4-Vinylpyridine Containing Cobalt Schist Base Carrier : Effect of Membrane Thickness and Carrier Concentration

  • Hong, Jae-Min;Kang, Yong-Soo
    • Macromolecular Research
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    • 제8권1호
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    • pp.1-5
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    • 2000
  • The valiclity of the simple mathematical model for facilitated transport in a solid state membrane developed previously has been examined againsts the carrier concentration and membrane thick-ness. Membranes are prepared with copolymer of styrene and 4-vinylpyridine as a matrix and Co(salen) as a carrier. 4-Vinylpyridine is incorporated to provide the coordination site for Co(salen) carrier. Oxygen permeability through the facilitated transport membrane is linearly increased with the square of its thick-ness, as predicted by the mathematical model. However, the oxygen permeability does not increase linearly with the carrier concentration. This seems to be due to the deactivation of the carrier by dimerization at high carrier concentrations as well as the reduced chain mobility by coordination of bulky Co(salen) carrier.

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Olefin Separation Performances and Coordination Behaviors of Facilitated Transport Membranes Based on Poly(styrene-b-isoprene-b-styrene)/Silver Salt Complexes

  • Lee, Dong-Hoon;Kang, Yong-Soo;Kim, Jong-Hak
    • Macromolecular Research
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    • 제17권2호
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    • pp.104-109
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    • 2009
  • Solid-state facilitated, olefin transport membranes were prepared by complexation of poly(styrene-b-iso-prene-b-styrene) (SIS) block copolymer and silver salt. Facilitated olefin transport was not observed up to a silver mole fraction of 0.14, representing a threshold concentration, above which transport increased almost linearly with increasing silver salt concentration. This was because firstly the silver ions were selectively coordinated with the C=C bonds of PI blocks up to a silver mole fraction of 0.20, and secondly the coordinative interaction of the silver ions with the aliphatic C=C bond was stronger than that with the aromatic C=C bond, as confirmed by FT-Raman spectroscopy. Small angle X-ray scattering (SAXS) analysis showed that the cylindrical morphology of the neat SIS block copolymer was changed to a disordered structure at low silver concentrations ($0.01{\sim}0.02$). However, at intermediate silver concentrations ($0.15{\sim}0.20$), disordered-ordered structural changes occurred and finally returned to a disordered structure again at higher silver concentrations (>0.33). These results demonstrated that the facilitated olefin transport of SIS/silver salt complex membrancs was significantly affected by their coordinative interactions and nano-structural morphology.

촉진수송 및 태양전지용 분리막 (Polymer Electrolytes and their Application to Solar Cells and Separation Membranes)

  • 강용수
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 첨단 분리막 연구동향
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    • pp.13-35
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    • 2004
  • Metal Complexes in Macromolecules Applications of Polymer Electrolyte Membranes Facilitated Transport in Solid State Roles of Electrolytes in Solar Cells - Electrolytes :ㆍI- and $I_3$-conductor ㆍelectron barrier or hole conductor ㆍelectrochemical redox reaction media ㆍinterfacial contactor for dye, $TiO_2$ and electrode ㆍmechanical separator (omitted)

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Polymer Electrolyte Membranes and their Applications to Membranes, Fuel Cells and Solar Cells

  • Kang, Yong-Soo
    • 한국막학회:학술대회논문집
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    • 한국막학회 2003년도 The 4th Korea-Italy Workshop
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    • pp.29-32
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    • 2003
  • Polymer electrolyte membranes are developed for the applications to facilitated transport membranes, fuel cells and solar cells. The polymer electrolyte membranes containing silver salt show the remarkably high separation performance for olefin/paraffin mixture in the solid state; the propylene permeance is 45 GPU and the ideal selectivity of propylene/propane is 15,000. For fuel cell membranes, the effects of the presence and size of the proton transport channels on the proton conductivity and methanol permeability were investigated. The cell performance for dye-sensitized solar cells employing polymer electrolytes are measured under light illumination. The overall energy conversion efficiency reaches 5.44 % at 10 ㎽/$\textrm{cm}^2$, to our knowledge the highest value ever reported in the polymer electrolytes.

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Analysis of Facilitated Transport Phenomena in Solid State Membrane III.

  • 홍재민;장정식;강용수;김은영;심정섭
    • 한국막학회:학술대회논문집
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    • 한국막학회 1992년도 추계 총회 및 학술발표회
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    • pp.37-38
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    • 1992
  • 혼합물 중의 특정 분자와 선택적, 가역적으로 반응하는 운반체를 이용한 촉진 수송법은 분리막의 투과도와 선택도를 동서에 증가시킬 수 있는 한 방법으로 많은 연구가 진행되어 왔다. 촉진수송의 개념은 처음 액막에서 발견되었으나 근래에는 고체막에서도 가능하다는 보고들이 있다. 액막의 경우는 이 현상을 설명하는 모델들이 다수 보고되었으나 운반체가 고정되어 있는 고체막에 대한 보고는 아직 초보적인 단계이다.

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고위험 신생아의 발뒤꿈치 천자 시 비영양성 흡철과 감싸주기가 통증완화에 미치는 효과 (Pain Relieving Effects of Nonnutritive Sucking and Facilitated Tucking on High Risk Infnats during Heelsticks Procedure)

  • 안원희
    • 부모자녀건강학회지
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    • 제8권2호
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    • pp.157-167
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    • 2005
  • The purpose for this study is to identify the effects of nonnutritive sucking and facilitated tucking as a pain management during painful heelstick procedure. This study was a repeated measurement design. Data were collected from Sep. 15, to Oct. 20, 2005. According to the criteria twenty seven high risk infants were selected from the NICU of university hospital. The behavioral state were evaluated with the PIPP(Prematures Infants Pain Profile. PIPP, heart rate, saturation were observed without versus with nonnutritive sucking and tucking care. Statistic analysis was conducted with a wilcoxon nonparametric test. The results of this study were as follows. Pina behavior responses in nonnutritive sucking and tucking cases were lower than without treatment(Z=-4.430, p=.000), Heart rate and heart rate recovery time in nonnutritive sucking and tucking cases were attenuate decrease in heart rate(Z=-2.694, p=.005) and statistical significant differences in periods (Z=-4.229, p=.000). But, Saturation was no significant differences(Z=-3.230, p=.000). In conclusion, the application of nonnutritive sucking and tucking as an pain relieg for high risk infants is nursing intervention in pain management ar heelsticks.

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원자력 발전소 주제어실 인터페이스 설계를 위한 인적오류 분석 기법의 보완 (A Modification of Human Error Analysis Technique for Designing Man-Machine Interface in Nuclear Power Plants)

  • 이용희;장통일;임현교
    • 대한인간공학회지
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    • 제22권1호
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    • pp.31-42
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    • 2003
  • This study describes a modification of the technique for human error analysis in nuclear power plants (NPPs) which adopts advanced Man-Machine Interface (MMI) features based on computerized working environment, such as LCOs. Flat Panels. Large Wall Board, and computerized procedures. Firstly, the state of the art on human error analysis methods and efforts were briefly reviewed. Human error analysis method applied to NPP design has been THERP and ASEP mainly utilizing Swain's HRA handbook, which has not been facilitated enough to put the varied characteristics of MMI into HRA process. The basic concepts on human errors and the system safety approach were revisited, and adopted the process of FMEA with the new definition of Error Segment (ESJ. A modified human error analysis process was suggested. Then, the suggested method was applied to the failure of manual pump actuation through LCD touch screen in loss of feed water event in order to verify the applicability of the proposed method in practices. The example showed that the method become more facilitated to consider the concerns of the introduction of advanced MMI devices, and to integrate human error analysis process not only into HRA/PRA but also into the MMI and interface design. Finally, the possible extensions and further efforts required to obtain the applicability of the suggested method were discussed.