• Title/Summary/Keyword: Ion-Exchange

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Recent Developments in Characterization of Ion-Exchange Membrane Processes: Impedance Spectroscopy for a Concentration Polarized Boundary Layer

  • Park, Jin-Soo;Moon, Seung-Hyeon
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.03a
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    • pp.1-11
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    • 2004
  • Ion-exchange membranes have been widely used in various applications such as diffusion dialysis, electrolysis, electrodialysis, fuel cell etc [1-2]. When an electric current passes through the membrane system, the current is carried by both positive and negative ions in the bulk solution phases, whereas it is carried mainly by the counter-ions in the membrane. (omitted)

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Purification and Characterization of ATPase and Phosphatase of Light Membrane Vesicles Isolated from Cucurbita pepo (Cucurbita pepo에서 분리한 Light Membrane Vesicle의 ATPase와 Phosphatase의 정제 및 특성)

  • 오승은
    • Journal of Plant Biology
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    • v.33 no.4
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    • pp.325-332
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    • 1990
  • Light membrane vesicles were isolated from the zucchini hypocotyl by floatation on ficoll density gradients and the proteins were solubilized with Triton X100. Three ATP-hydrolyzing enzymes were partially purified by ion-exchange and gel filtration chromatography and isoelectric focusing. There are plasma membrane-type ATPase whose activity was inhibited by vanadate but not by nitrate, tonoplast-type ATPase which was sensitive to nitrate but insensitive to vanadate and one having a phosphatase activity with a pI value different from that of an acid phosphatase. A fraction was obtained after DEAE-ion-exchange chromatography crossreacting with polyclonal antibodies against Ca2+ -ATPase from human erythrocytes.

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수산화인회석에 Ru를 도입한 이종상 촉매의 합성및 특성 평가

  • Kim, Dae-Hyeon;Gwon, Gi-Yeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.209.1-209.1
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    • 2014
  • 수산화인회석(Hydroxyapatite)는 뼈와 이빨의 무기물의 주성분으로서 칼슘과 인산염으로 구성된다. 본 실험에서는 다양한 농도의 염기조건(NaOH 0,2,4,5,10 M)하에서 서로 다른 형태의 수산화인회석을 수열합성법(hydrothermal method)을 이용해 합성하였다. 합성된 각각의 수산화인회석을 XRD로 확인하였고 일정 농도 이하에서는 octacalcium phosphate이 함께 존재한다는 것을 확인하였다. 수산화인회석 표면에 Ru를 Ion-exchange 반응을 통하여 도입하였으며, 도입된 표면을 TEM을 확인하였다. Ru를 도입한 수산화인회석을 benzyl alcohol과 benzyl amine을 산화반응에 응용하였다.

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Transport Properties of Charged Mosaic Membrane Based on Non-equilibrium Thermodynamics

  • Song, Myung-Kwan;Yang, Wong-Kang
    • Korean Membrane Journal
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    • v.7 no.1
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    • pp.67-70
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    • 2005
  • It is well known as the role of ion exchange membrane with functional group in membrane matrix. Recently, we were reported that the charged mosaic membrane within parallel array of negative and positive charge groups. In this study we are reported the properties for the various transport coefficients of metal and heavy metal ions across charged mosaic membrane based on non-equilibrium thermodynamics is not based on equilibrium state.

Intercalation of Ca-montmorillonite with Decylammonium Ion and n-Alcanol (Decylammonium 이온과 n-Alcanol 분자에 의한 Ca-montmorillonite의 Intercalation)

  • 최진호;김창은;형경우
    • Journal of the Korean Ceramic Society
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    • v.20 no.3
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    • pp.205-210
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    • 1983
  • The determination of charge density and charge distribution in montmorillonite are discussed. The method is based on cation exchange of the inorganic interlayer cations against decylammonium ion and molecular intercalation of n-alcanol. The results obtained from Yougil-bentonite show that charge density of 0.37 per unit formula and cation exchange capacity of 102.5 meq/100g.

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Purification and Some Physicochemical Study of Bacillus cereus $\beta$-Amylase (Bacillus cereus $\beta$-아밀라아제의 정제 및 이화학적 성질)

  • 송예헌
    • The Korean Journal of Food And Nutrition
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    • v.6 no.4
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    • pp.307-313
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    • 1993
  • Bacillus cereus $\beta$-amylase was purified by Sephadex G-100 gel filtration, CM Sephadex C-50 ion exchange chromatography and CM Sephadex C-50 ion exchange rechromatography The purified enzyme showed 871 unit/mg of specific activity. The purified enzyme was identified as homogenious by disc PAGE, SDS-PAGE and analysis of reaction product. The purified enzyme showed optimum pH 7.0. optimum temperature 5$0^{\circ}C$, and was stable at 0~5$0^{\circ}C$ and at pH range of 6~10.

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$^{13}C$ NMR Studies of the Chelate Ring Opening-Closing Process in (Nitrilotriacetato)vanadate(V) dioxovandate(V) Ion

  • Lee, Man-Ho;Schaumburg, Kjeld
    • Bulletin of the Korean Chemical Society
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    • v.11 no.5
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    • pp.399-402
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    • 1990
  • Activation parameters of the exchange between two types of glycinate groups in (nitrilotriacetato)dioxovanadate(V) ion, $[VO_2(NTA)]^{2-}$, have been determined as the results of $^{13}C$ NMR measurements over a range of temperatures between 277 and 306$^{\circ}K$. The exchange mechanism is proposed on the basis of the chelate ring opening-closing process, assuming rupture of the metal-oxygen (glycinate) bond trans to V = O bond to give a five-coordinated intermediate.

Preparation of an Anion Exchange Membrane Using the Blending Polymer of Poly(ether sulfone) (PES) and Poly(phenylene sulfide sulfone) (PPSS) (폴리에테르설폰-폴리페닐렌설파이드설폰 블렌딩 고분자를 이용한 음이온교환막의 제조)

  • Lee, Kyung-Han;Han, Joo-Young;Ryu, Cheol-Hwi;Hwang, Gab-Jin
    • Membrane Journal
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    • v.29 no.3
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    • pp.155-163
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    • 2019
  • The anion exchange membrane using the blending polymer of poly(ether sulfone) and poly(phenylene sulfide sulfone) was prepared. It was confirmed by EDXS and FT-IR analysis that the prepared anion exchange membrane had the -N- as an anion exchange group. The ionic conductivity in 1 mol/L $H_2SO_4$ aqueous solution was measured. The ionic conductivity of the prepared anion exchange membrane was 0.015~0.083 S/cm, and had a high value compared with AFN and APS as a commercial anion exchange membrane. Permeabilities of the vanadium ions through the prepared anion exchange membrane were tested to evaluate the possibility as a separator in vanadium redox flow battery. Vanadium ion permeation rate in the prepared anion exchange membrane had a low value compared with Nafion 117 as a commercial cation exchange and AFN as a commercial anion exchange membrane.

A Study on the Adsorption Characteristics of Nitrogen and Oxygen on Ion Exchanged Zeolite Adsorbents (이온교환된 제올라이트 흡착제의 질소 및 산소 흡착 특성 연구)

  • Jeong, Heon-Do;Kim, Dong-Sik;Kim, Kweon-Ill
    • Applied Chemistry for Engineering
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    • v.16 no.1
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    • pp.123-130
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    • 2005
  • Zeolite X adsorbents with large surface area were prepared for using oxygen PSA adsorbent. Selective adsorption performance of nitrogen on the synthesized zeolite X adsorbent was improved by the cation exchange of adsorbent. The zeolite X which had over $650m^2/g$ surface area was synthesized at the conditions of $SiO_2\;:\;Na_2O\;:\;H_2O\;:\;Al_2O_3$ = 2.5 : 3.5 : 150 : 1 mole ratio, $98^{\circ}C$ temperature and 18 h synthesized time in 50 L reactor. The metal ions Li, Ag, Ca, Br, Sr, etc. were investigated for ion exchange with zeolite X. Ag ion was showed the highest ion exchange rate among these metal ions and all metal ions were exchanged with Na ion at equivalent rate. Compared with the NaX adsorbent, the ion exchanged zeolite X adsorbent remarkably improved its adsorption performance of nitrogen at the conditions of $10{\sim}40^{\circ}C$ temperature and 0~9 atm pressure. At an equilibrium pressure under 0.5 atm, adsorption performance of nitrogen on the ion exchanged zeolite adsorbent increased in the order of Ag > Li > Ca > Sr> Ba > K, whereas at an equilibrium pressure over 1 atm showed in the order of Li > Ag > Ca > Sr > Ba > K. Nitrogen/oxygen separation factor of Li ion exchanged zeolite X adsorbent was 13.023 at the partial pressure of nitrogen/oxygen gas mixture similar to air and $20^{\circ}C$ adsorption temperature.