• Title/Summary/Keyword: Membrane transport

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Beneficial Effect of Scutellaria baicalensis Georgi Extract on Mercury Chloride-Induced Membrane Transport Dysfunction in Rabbit Renal Cortical Slices (황금약침액(黃芩藥鍼液)이 가토(家兎) 신피질절편(腎皮質切片)에서 수은(水銀)에 의한 세포막(細胞膜) 물질이동(物質移動) 기능장애(機能障碍)에 미치는 영향(影響))

  • Kim, Hong-Soo;Song, Choon-Ho
    • Journal of Pharmacopuncture
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    • v.4 no.2
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    • pp.49-56
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    • 2001
  • This study was undertaken to determine whether Scutellaria baicalensis Georgi (SbG) extract exerts the protective effect against $HgCl_2$-induced alterations in membrane transport function in rabbit renal cortical slices. The slices were treated with 0.1 mM $HgCl_2$ for 60 min at $37^{\circ}C$. $HgCl_2$ caused an inhibition in PAH uptake by renal cortical slices. Such an effect was accompanied by depressed $Na^+-K^+$-ATPase activity and ATP depletion. SbG prevented $HgCl_2$-induced inhibition of PAH uptake in a dose-dependent manner at the concentration ranges of 0.01-0.1%. $HgCl_2$-induced inhibition of $Na^+-K^+$-ATPase activity and ATP depletion were significantly prevented by 0.05% SbG. These results suggest that SbG prevents $HgCl_2$-induced alterations in membrane transport function in rabbit renal cortical slices. Such protective effects of SbG may be attributed to inhibition of peroxidation of membrane lipid.

PEBAX-2533/Ag Salt/Al(NO3)3 Composite Using AgCF3SO3 for Facilitated Olefin Transport Membrane (올레핀 촉진수송 분리막용 AgCF3SO3를 활용한 PEBAX-2533/Ag Salt/Al(NO3)3 복합체)

  • Kim, Soyoung;Kang, Sang Wook
    • Membrane Journal
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    • v.31 no.1
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    • pp.61-66
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    • 2021
  • This study was a study on an facilitated transport membrane to replace the cryogenic separation method currently used in olefin/paraffin separation. Cost reduction is also a very important factor to commercialize facilitated transport membranes. However, AgBF4, which has been studied a lot, is a relatively expensive silver salt. To replace this, a PEBAX-2533/ AgCF3SO3/Al(NO3)3 composite film was prepared using relatively inexpensive AgCF3SO3. It was analyzed through SEM, FT-IR, and RAMAN. Through this study, it was confirmed that the polymer matrix affects the long-term stability.

Studies on the Macrocycle mediated Transport in a Bulk Liquid Membrane System of Transition Metal Ions

  • Cho, Moon-Hwan;Seon-Woo, Kie-Hwa;Heo, Moon-Young;Lee, In-Chong;Yoon, Chang-Ju;Kim, Si-Joong
    • Bulletin of the Korean Chemical Society
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    • v.9 no.5
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    • pp.292-295
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    • 1988
  • Macrocyclic ligands have been studies as cation carriers in a bulk liquid membrane system. $Cu^{2+}$ has been transported using nitrogen substituted macrocycles as carriers and several transition metal ions($M^{n+}\;=\;Mn^{2+},\;Co^{2+},\;Ni^{2+},\;Cd^{2+},\;Pb^{2+}\;and\;Ag^{+}$) have been transported using $DBN_3O_2,\;DBN_2O_2,\;Me_6N_414C4$ and DA18C6 as carriers in a bulk liquid membrane system. Competitive $Cu^{2+}-M2^+$ transport studies have also been carried out for the same system. In single cation transport experiments, the best macrocyclic ligand for transport is a ligand that gives a moderately stable rather than very stable complex in the extraction. However, when both cations are present in the source phase, the cation which forms the most stable complex with carrier is favored in transport over other cations. Generally, the nitrogen substiituted macrocycles transport $Cu^{2+}$ selectively over $Mn^+$. Ligand structure, equilibrium constant (or stability constant) for complex formation, source phase pH and carrier concentration are also important parameters in transport experiments.

Transport of Zinc Ion in a Contained Liquid Membrane Permeator with Two Micro-Porous Films (지지막을 이용하는 액막 추출기 내에서 아연 이온의 이동)

  • 주창식;이석희;이민규;홍성수;하홍두;정석기
    • Journal of Environmental Science International
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    • v.9 no.2
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    • pp.159-164
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    • 2000
  • For the purpose of development of a liquid membrane permeator which separates metal ions from aqueous solutions continuously and effectively, a continuous membrane permeator with the membrane solution trapped between extraction and stripping phases by two micro-porous hydrophilic films was manufactured. Experimental researches on the separation of zinc ion from aqueous solutions were performed in the liquid membrane permeator with 30 vol % D2EHPA solution in kerosine as liquid membrane. As results, the liquid membrane permeator separates zinc ion from aqueous solutions continuously and effectively in the wide range of operating conditions. A simple mass transfer rate model using equilibrium constant of the extraction reaction for the system used were proposed, and the model was compared with experimental results of separation of zinc ion in the permeator. And the effects of operating factors, such as space time, pH of extraction solution, extraction temperature, on the separation rate of zinc ion in the permeator were experimentally examined.

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Moisture Permeation Characteristics of Hollow Fiber Membrane Tube for Humidification According to Input Conditions of Wet Steam (습증기 투입 조건에 따른 가습용 중공사막 튜브 수분 투과 특성)

  • CHAE, JONGMIN;YU, SANGSEOK
    • Transactions of the Korean hydrogen and new energy society
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    • v.29 no.6
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    • pp.620-626
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    • 2018
  • Recently, fuel cell field is receiving much attention as an environmentally friendly energy in the world. Among the various types of fuel cells, in the case of PEMFC, ions move through the membrane in the middle of the unit cell. Therefore, proper moisture is required inside the PEMFC. In the case of membrane type humidifier, flat membrane or hollow fiber membrane is mainly used. Since various parameters can change the performance, the performance investigation has to be carried out with parameters. In this study, water transport of hollow fiber membrane was investigated in terms of principle operating conditions such as temperature and flow rate.

Highly Selective Transport of Ag+Ion through a Liquid Membrane Containing 2-Mercaptobenzothiazole as a Carrier

  • Akhond, Morteza;Tashkhourian, Javad
    • Bulletin of the Korean Chemical Society
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    • v.24 no.4
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    • pp.489-493
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    • 2003
  • 2-Mercaptobenzothiazole was used as a highly selective and efficient carrier for the uphill transport of silver ion through a chloroform bulk liquid membrane. In the presence of thiosulfate ion as a suitable metal ion acceptor in the receiving phase, the amount of silver transported across the liquid membrane after 180 min was 90 ± 3.0%. The selectivity and efficiency of silver ion transported from aqueous solutions containing equimolar mixtures of $Zn^{2+}, Cu^{2+}, Co^{2+}, Ni^{2+}, Cd^{2+}, Pb^{2+}, Bi^{3+}, Fe^{2+}, Fe^{3+}, Pd^{2+}, Mn^{2+}, Hg^{2+}, Sn^{2+}, Ca^{2+}, Mg^{2+}, K^+, Na^+ and Li^+$ were investigated.

PET Fabric Supported Fixed Site Carrier Membrane for Selective Metal ion Transport

  • Jin, Long Yi;Mah, Soukil
    • Fibers and Polymers
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    • v.3 no.1
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    • pp.14-17
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    • 2002
  • Development of a novel fixed site carrier membrane (FCM), supported by PET fabric for metal ion separation is reported. The membranes were prepared by dipping PET fabric into the methylene chloride solution of Poly(5-vinyl-m-phe-nylene-m'-phenylene-32-crown-10) (P(VCE)), a polymeric metal ion carrier. It was found that the flux of mono-valent metal ion transported across the membrane is signif=cantly differed from each other and the flux decreases in the order $Cs^+$>$Rb^+$>$K^+$>$Na^+$>$Li^+$ irrespective to the anion except perchlorate anion. It was explained in terms of the stability of the complex, formed by crown ether unit of the P(VCE) and the various metal ions, meanwhile, the lower rate of transport in the presence of perchlorate anion was ascribed to its low hydrophilicity.

Mechanisms of Gas Permeation through Microporous Membranes - A Review (미세 다공막을 통한 기체 투과기구)

  • 황선탁
    • Membrane Journal
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    • v.7 no.1
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    • pp.1-10
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    • 1997
  • A review is presented for various gas transport mechanisms through microporous membranes of both polymeric and inorganic materials. Different transport modes manifest depending on the pore size and the flow regime, which is a function of pressure, temperature, and the interaction between gas molecules and the pore walls. For microporous membranes whose pores are small and the internal surface area huge, the surface diffusion becomes a significant factor. If the pores become even smaller, then the transport mechanism will be more of an activated diffusion type. When conditions are right capillary condensation will take place to create an enormous capillary pressure gradient, which will greatly enhance the permeation flux. At the same time the capillary condensate of the heavier component may block the membrane pores denying the passage of the lighter gas molecules. All of these phenomena will influence the separation of mixtures.

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Gas transport properties of alumina composite membranes

  • Lee, Hong-Joo;Hiroyuki Yamauchi;Hiroyuki Suda;Kenji Haraya
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05a
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    • pp.128-131
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    • 2004
  • The composite mesoporous ceramic membranes were prepared with ${\gamma}$-alumina and poly (2, 6-dimethyl-l, 4-pyphenylene oxide) (PPO) on the surface of the macroporous $\alpha$-alumina ceramic membranes and the permeation results were compared with those of the $\alpha$-alumina membrane for large-scale applications. In the results of the transport experiments, the ceramic membranes gave high gas permeances mainly due to Knudsen diffusion and surface diffusion as an additional mechanism. And, the polymer modification increased the permeances of the strongly adsorbing gas components. In this study the modifications of alumina ceramic membranes could increase the gas permeation performances especially for the strongly absorbing gas components.

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