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Volume 45, Issue 1
Displaying 1-4 of 4 articles from this issue
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Kosuke Izutsu1999 Volume 45 Issue 1 Pages 1
Published: May 20, 1999
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (161K) -
Munetaka OYAMA1999 Volume 45 Issue 1 Pages 2-16
Published: May 20, 1999
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSBy connecting a column electrolysis method with a stopped-flow technique, a pulse-electrolysis stopped-flow method has been developed. This method has many advantages that it can be applied to the detection and characterization of unstable intermediates as well as the analysis of the reaction kinetics of heterogeneous electrode reactions as homogeneous reactions. In addition, this method can be utilized combined with various spectroscopic methods including UV-visible, resonance Raman (RR) and electrogenerated chemiluminescence (ECL) measurements. In this review, the advantages of this method are demonstrated with many successful results in the analyses of the reaction kinetics and mechanisms involving electrogenerated species obtained by using the pulse-electrolysis stopped-flow method.View full abstractDownload PDF (2139K) -
Hidekazu DOE1999 Volume 45 Issue 1 Pages 17-24
Published: May 20, 1999
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSSince interesting selectivity for K+ over Na+ by naphtho-15-crown-5 (N15C5) has been reported in studies of ion-selective electrode and solvent extraction, the ion-transfers of alkali and alkaline earth metal cations facilitated by N15C5 have been studied electrochemically at ITIES, Interface of Two Immiscible Electrolyte Solutions between an aqueous and an organic (nitrobenzene or 1, 2-dichloroethane) phases. It is clearly observed that K+ and Ca2+ transfer across the ITIES forming 1:2 (cation to ligand) complex but the other metal ions forming 1:1 complex. Then the values of some equilibrium constant in the course of the interfacial transfer are in beautiful agreement between the electrochemical and the solvent extraction results. The stoichiometries of those complex ions have been also studied by electrospray ionization mass spectrometry directly. These results have partly supported the conclusions from the electrochemical study. Interestingly, on the other hand, it has been also observed that a bilayer phospholipid membrane doped by N15C5 selects K+ over Na+.View full abstractDownload PDF (1025K) -
Yumi YOSHIDA1999 Volume 45 Issue 1 Pages 25-43
Published: May 20, 1999
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSEquations were derived for the quantitative expressions of distribution ratios, D, in ion pair extractions of a cation, i+, with a counter ion, x- from water, W, to organic, O, in the absence and presence of a special complexing neutral ligand, Y, in O by using standard transfer free energies of i+ and x- from W to O, ion pair formation constants of i+ with x- in W and O, the stability constant of the complex, (iYp)+, in O and the ion pair formation constant of (iYp)+ with x- in O. The D calculated by substituting the constants determined by electrochemical methods into the derived equations agreed very well with those obtained experimentally by the ion pair extraction, which means that the extraction processes assumed in the derivation of the equations have been reasonable. Distribution . ratios in ion pair extraction were connected quantitatively to the potentials, EISE, and selectivity coefficients, Kpotj, at an ion selective electrode, ISE, of liquid membrane type, taking into account that all of EISE, Kpotij and D could be expressed physicochemically by using standard Galvani potential differences (or standard free energies ) for ion transfers from W to the ISE membrane, M, or O, stability constants of complexes with a neutral ligand in M or O and formation constants of ion pairs with coexisting counter ions in M or O. Theoretical equations derived from the relations between EISE and Kpotij and D were verified experimentally.View full abstractDownload PDF (2127K)
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