• Journal of Korean Society of Water and Wastewater
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• v.28 no.1
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• pp.83-89
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• 2014

The aim of this study is to investigate the sorption/ion exchange of radioactive nuclides such as $Cs^+$ and $Sr^{2+}$ by synthetic Na-micas. In order to prepare Na-micas, two natural micas (phlogopite and biotite) were used as precursor materials. XRD, SEM, and EDS analyses were used to examine material characterization of synthetic Na-micas. Analyses of materials revealed that Na-micas were successfully obtained from natrual micas by K removal treatment. On the other hand, single solute (Cs or Sr) and bi-solute (Cs/Sr) sorption experiments were carried out to determine sorption capacity of Na-micas for Cs and Sr under different pH and ionic strength conditions. Uptake of Cs and Sr by micas in bi-solute system was lower than in single-solute system. Additionally, Langmuir and Langmuir competitive models were applied to describe sorption isotherm of Na-micas. bi-solute system was well described by Langmuir competitive models. For the results obtained in this study, Na-micas could be promising sorbents to treat multi-radioactive species from water and groundwater.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.160-160
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• 1993

목적: Guinea pig heart의 ATP sensitive $K^{＋}$ channel xenopus oocyte에 발현시켜 연구하고져 본 실험을 행하였다. 실험방법: 기니픽 심장으로부터 ,RNA를 분리하여 50ng/$\mu$l의 농도로 50nl를 xenopusdp 주입하였다. Xenpus oocyte에서 conventional electrode를 이용 막전휘를 측정하였고, pH selective 미세전극으로 세포내 pH를 측정하였다. 막전위에 미치는 potassium channel opener, blocker, KCN의 작용을 관찰하였다. 결과: 기니픽 심장 mRNA를 주입하거나 주입하지 않은 xenopus oocyte에서 $K^{＋}$channel opener인 cromakalin, RP49356등은 과분극을 일으키지 못하였다. 그러나 세포내 ATP 감소제인 KCN은 농도 의존적으로 과분극을 일으켰으나 ,glibenclamide에 의해 차단되는 않았다. mRNA를 주입한 oocyte에서 Na-H 자극제인 NH$_4$Cl은 pH 변동을 일으켜 NA-H exchange를 expression 시켰다. 결론: Xenopus oocyte는 cromakalin등에 의해 open되는 $K^{＋}$channel 은 없었고, 기니픽 심근의 ATP sensitive $K^{＋}$channel로 expression 되지 않았으나 Na-H exchange 는 expression 됨을 알 수 있었다. KCN으로 open 되는 $K^{＋}$channel이 있었으나 glibenclamide에는 차단되지 않는 channel이였다.

• Korean Journal of Materials Research
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• v.26 no.9
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• pp.498-503
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• 2016

The characteristics of aqueous lithium recovery by ion exchange were studied using three commercial cation exchange resins: CMP28 (porous type strong acid exchange resin), SCR-B (gel type strong acid exchange resin) and WK60L (porous type weak acid exchange resin). CMP28 was the most effective material for aqueous lithium recovery; its performance was even enhanced by modifying the cation with $K^+$. A comparison to $Na^+$ and $H^+$ form resins demonstrated that the performance enhancement is reciprocally related to the electronegativity of the cation form. Further kinetic and equilibrium isotherm studies with the $K^+$ form CMP28 showed that aqueous lithium recovery by ion exchange was well fitted with the pseudo-second-order rate equation and the Langmuir isotherm. The maximum ion exchange capacity of aqueous lithium recovery was found to be 14.28 mg/g and the optimal pH was in the region of 4-10.

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.43-44
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• 2002

Basically all cells have the recovery mechanisms from the shift of intracellular pH (pHi). Many mechanisms were found and characterized. Generally the recovery mechanisms from acidosis are Na$\^$＋/-dependent, such as Na$\^$＋/-H$\^$＋/ exchange and Na$\^$＋/-HCO$_3$-symport. The recovery mechanism from alkalosis are Cl-dependent, such as Cl$\^$-/-HCO$_3$-exchange and Cal$\^$-/-OH$\^$-/ exchange.(omitted)

• The Journal of Engineering Research
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• v.4 no.1
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• pp.109-118
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• 2002

In this research, the cation-exchange-reactions between Na-Montmorillonite and betaine compound, $R_{11}SO_4$, with acid group at the end of alkyl chain were performed under the general condition with dist. water including $CO_2$ and under the different pH-conditions with dist. water without $CO_2$, and their behaviors were observed. As results the exchange reaction under the general condition was perfectly finished after 49 h exchange time, and the basal spacings obtained under the exchange solution and after washing with methanol and drying in high vacuum were 23.6, 17.1 and $15.0\AA$, respectively. The basal spacings obtained under pH-exchange solution after exchange time under different pH-values lied between about 24.7 and $25.6\AA$ independently of the pH-values, and those measured after drying on the air and in high vacuum were about $20.0\AA$ and $13.8~14.4\AA$, respectively.

• Journal of the Korean Ceramic Society
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• v.21 no.3
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• pp.217-220
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• 1984

The leaching of Na-fluor-tetrasilicic mica $NaMg_{2.5}(Si_4O_{10})F_2$ (Na-TSM) in the deionized water was investigated by measuring the pH released Na and Mg contents in the suspension. According to the results it was found that $Na^+$ ions of interlayer in the Na-TSM were easily replaced by $H^+$ ions from the deionized water because $Na^+$ ions of I were repidly diffused to form a large hydrated electric double layer in the suspension.

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.281-293
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• 1988

The effect of pH on the rate of PAH uptake was studied in rabbit renal basolateral membrane vesicles (BLMV) and brush border membrane vesicles (BBMV). In the absence of Na in incubation medium, a decrease in external $pH(pH_0)$ led to an increase in probenecid-sensitive PAH uptake by BLMV. In the presence of Na, the probenecid-sensitive PAH uptake was unaltered when the $pH_0$ decreased from 8.0 to 6.0 but further decrease in $pH_0$ to 5.5 increased significantly the uptake. The probenecid-sensitive PAH uptake was not affected by an alteration in pH per se in the absence of a pH gradient with or without the presence of Na. However, the presence of Na stimulated the probenecid-sensitive PAH uptake in all pH ranges tested over that measured in the absence of Na. A similar pattern of pH dependence on the PAH uptake was observed in BBMV but the presence of Na did not alter the probenecid-sensitive PAH uptake in the presence and absence of a pH gradient. Kinetic analysis for BLMV showed that Na or pH gradient increased Vmax of the probenecid-sensitive PAH uptake without a change in Km value. These results suggest that PAH is transported by $OH^-/PAH$ exchange process in the luminal membrane, but the pH dependence in the BLMV is not unequivocally consistent with an anion exchange process. The PAH transport is dependent on Na in BLMV but not in BBMV.

• Bulletin of the Korean Chemical Society
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• v.22 no.1
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• pp.53-58
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• 2001

Sulfonated poly(phenylene sulfide) (SPPS) polymers were prepared by sulfonation of poly[methyl[4-(phenylthio) phenyl]sulfonium trifluoromethanesulfonate] (PPST) with fumic sulfonic acid (10% $SO_3-H_2SO_4$) and demethylation with aqueous NaOH solution. The equilibrium constants of ion exchange reactions between alkali metal cations ($Li^+,\;Na^+,\;and\;K^+$) and SPPS ion exchanger in organic solvents such as tetrahydrofuran (THF) and dioxane were measured. The equilibrium constants of ion exchange reactions increased as the polarity of the solvent increased, and the reaction temperature decreased. The equilibrium constants of the ion exchange reaction ($K_{eq}$) also increased in the order of $Li^+,\;Na^+,\;and\;K^+$. To elucidate the spontaneity of the exchange reaction in organic solvents, the enthalpy, entropy, and Gibbs free energy were calculated. The enthalpy of reaction ranged from -0.88 to -1.33 kcal/mol, entropy ranged from 1.42 to 4.41 cal/Kmol, and Gibbs free energy ranged from -1.03 to -2.55 kcal/mol. Therefore, the exchange reactions were spontaneous because the Gibbs free energies were negative. The SPPS ion exchanger and alkali metal ion bounding each other produced good ion exchange capability in organic solvents.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.659-665
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• 2012

IgY (Immunoglobulin Yolk) in egg yolk corresponds to IgG (Immunoglobulin G) in animal serum and plays an important role as immunological proteins in intestines. Carrageenan and Arabic gum were used as pretreatment agents to purify IgY from fresh egg yolk. DEAE (Diethylaminoethyl) Sepharose column in FPLC (Fast Protein Liquid chromatography) was an ion exchange tool to remove contaminants as well as to elute IgY from the column. GF HPLC (Gel Filtration High Performance Liquid Chromatography) enables to measure the molecular weights of IgY and to identify the purified IgY by comparing the molecular weight of standard IgY with the purified one. IgY is a heterogeneous group of different molecular weight and ionic properties, which was investigated with various IE HPLC (Ion Exchange High Performance Liquid Chromatography) columns such as AX, CX and SCX. Three peaks of IgY were separated in the AX column under the conditions of 0.5 M NaCl and pH=8. The SCX column also gave the three peaks of IgY at 0.5 M NaCl and pH=5.

• Journal of the Korean Chemical Society
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• v.15 no.6
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• pp.366-369
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• 1971

The cation exchange chromatographic method for the analysis of Babbitt metal has been studied. The quantitative separation of the mixture of Sb, Cu, Pb, and Sn ions has been obtained by elution, through 5cm column of resin, Rexyn 101 (Na form, 100~200 mesh), using 0.1 M NaCl solution for Sb, pH 4.5 and pH 7 solution of 0.01 M Na-Citrate + 0.1 M $NaNO_3$ for Cu and Pb, and 2NHCl solution for Sn as eluent.