• 제목/요약/키워드: Ligand-Free Electrode

검색결과 2건 처리시간 0.017초

이온운반물을 사용치 않은 이온 선택성 막의 특성 (Response Characteristics of Ligand Free PVC Membranes)

  • 김영학;이지연;정문모;김은정;허문희;안문규
    • 분석과학
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    • 제10권6호
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    • pp.453-458
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    • 1997
  • poly(vinyl chloride)와 가소제만으로 된 막을 제조하여 몇 가지 염기성 의약품에 대한 감응 특성을 조사하여 보았다. 감응막을 초기의 전위값으로 빨리 되돌리기 위하여 황산으로 처리하였다. chlorpromazine을 정량할 때 2-nitrophenyl octyl ether을 사용한 막에서 $10^{-6}{\sim}10^{-3}M$, dioctyl PhenylPhosphnate, isododecyl phenylphosphate, dioctyl maleate 등의 경우 $10^{-6}{\sim}10^{-2}M$까지의 직선성 검량선을 얻을 수 있었고, 항생제, 당, 그리고 1급 아민화합물에 대한 감응선은 적게 나타났다.

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Electrochemical Behavior of Mordant Red 19 and its Complexes with Light Lanthanides

  • Sang Kwon Lee;Taek Dong Chung;Song-Ju Lee;Ki-Hyung Chjo;Young Gu Ha;Ki-Won Cha;Hasuck Kim
    • Bulletin of the Korean Chemical Society
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    • 제14권5호
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    • pp.567-574
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    • 1993
  • Mordant Red 19(MR19) is reduced at mercury electrode at -0.67 V vs. Ag/AgCl with two electrons per molecule in pH 9.2 buffer by differential pulse polarography and linear sweep voltammetry. The peak potential is dependent on the pH of solution. The exhaustive electrolysis, however, gives 4 electrons per molecule because of the disproportionation of the unstable hydrazo intermediate. The electrochemical reduction of lanthanide-MR19 complexes is observed at more cathodic potential than that of free ligand. The difference in peak potentials between complex and free ligand varies from 75 mV for $La^{3+}$ to 165 mV for $Tb^{3+}$ and increases with increasing the atomic number of lanthanide. The electrochemical reduction of lanthanide complexes with MR19 is due to the reduction of ligand itself, and it can be potentially useful as an indirect method for the determination of lanthanides. The shape of i-E curves and the scan rate dependence indicates the presence of adsorption and the adsorption was confirmed by potential double-step chronocoulometry and the effect of standing time. Also the surface excess of the adsorbed species and diffusion coefficients are determined. The composition of the complex is determined to be 1 : 2 by spectrophotometric and electrochemical methods.