• Title/Summary/Keyword: Electrochemical Method

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Voltammetric Determination of Bisphenol A Using a Carbon Paste Electrode Based on the Enhancement Effect of Cetyltrimethylammonium Bromide (CTAB)

  • Huang, Wensheng
    • Bulletin of the Korean Chemical Society
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    • v.26 no.10
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    • pp.1560-1564
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    • 2005
  • The influence of cetyltrimethylammonium bromide (CTAB) on the electrochemical behavior of bisphenol A at the carbon paste electrode (CPE) was investigated. CTAB, with a hydrophobic C-H chain, can adsorb at the CPE surface via hydrophobic interaction and then change the electrode/solution interface, and finally affects the electrochemical response of bisphenol A, confirming from the remarkable oxidation peak current enhancement. The electrode process of bisphenol A was examined, and then all the experimental parameters which affects the electrochemical response of bisphenol A, such as pH value of the supporting electrolyte, accumulation potential and time, potential scan rate and the concentration of CTAB, were examined. Finally, a sensitive and simple voltammetric method was developed for the determination of bisphenol A. Under the optimum conditions, the oxidation peak current of bisphenol A varied linearly with its concentration over the range from $2.5\;{\times}\;10^{-8}\;to\;1\;{\times}\;10^{-6}$ mol/L, and the detection limit was found to be $7.5\;{\times}\;10^{-9}$ mol/L. This method was successfully employed to determine bisphenol A in some waste plastic samples.

A study on SOI structures thinning by electrochemical etch-stop (전기화학적 식각정지에 의한 SOI 박막화에 관한 연구)

  • 강경두;정수태;류지구;정재훈;정귀상
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.11a
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    • pp.583-586
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    • 2000
  • The non-selective method by polishing after grinding was used widely to thinning of SDB SOI structures. This method was very difficult to thickness control of thin film, and it was dependent on equipments. However electrochemical etch-stop, one of the selective methods, was able to accurately thickness control and etch equipment was very simple. Therefore, this paper described with the effect of leakage current and electrodes on electrochemical etch-stop. Consequentially, PP(passivation potential) was changed according to the kinds of contact and contact sizes, but OCP(open current potential) was not change with range of -1.5~-1.3V

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The Fabrication of a SDB SOI Substrate by Electrochemical Etch-stop (전기화학적 식각정지에 의한 SDB SOI기판의 제작)

  • 정귀상;강경두
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.5
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    • pp.431-436
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    • 2000
  • This paper describes on the fabrication of a SOI substrate by SDB technology and electrochemical etch-stop. The surface of the thinned SDB SOI substrate is more uniform than that of grinding or polishing by mechanical method and this process was found to be a very accurate method for SOI thickness control. During electrochemical etch-stop leakage current versus voltage curves were measured for analysis of the open current potential(OCP) point the passivation potential(PP) point and anodic passivation potential. The surface roughness and the controlled thickness selectivity of the fabricated a SDB SOI substrate were evaluated by using AFM and SEM respectively.

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DISCHARGE CHARACTERISTICS OF NICKELOXIDE ELECTRODE PREPARED FROM ELECTROCHEMICAL IMPREGNATION

  • Takenoya, K.;Sasaki, Y.;Yamashita, T.
    • Journal of the Korean institute of surface engineering
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    • v.32 no.3
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    • pp.363-365
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    • 1999
  • The improved method comprises electrochemically deposition of nickel hydroxide into the sintered nickel plaque cathode from nickel aqueous electrolyte at acid pH in a treating zone containing an anode. The electrochemical impregnation was examined under various conditions. Deposition condition of fine active material was obtained from the impregnation of a high temperature and also high current density. This method also could be decreased swelling and buckling of the plaque. A nickel electrode prepared by electrochemical impregnation is useful as the positive in nickel-cadmium cells. The utilization of the active material indicated almost 100% based on a one electron charge.

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Principles and Applications of Galvanostatic Intermittent Titration Technique for Lithium-ion Batteries

  • Kim, Jaeyoung;Park, Sangbin;Hwang, Sunhyun;Yoon, Won-Sub
    • Journal of Electrochemical Science and Technology
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    • v.13 no.1
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    • pp.19-31
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    • 2022
  • Lithium-ion battery development is one of the most active contemporary research areas, gaining more attention in recent times, following the increasing importance of energy storage technology. The galvanostatic intermittent titration technique (GITT) has become a crucial method among various electrochemical analyses for battery research. During one titration step in GITT, which consists of a constant current pulse followed by a relaxation period, transient and steady-state voltage changes were measured. It draws both thermodynamic and kinetic parameters. The diffusion coefficients of the lithium ion, open-circuit voltages, and overpotentials at various states of charge can be deduced by a series of titration steps. This mini-review details the theoretical and practical aspects of GITT analysis, from the measurement method to the derivation of the diffusivity equation for research cases according to the specific experimental purpose. This will shed light on a better understanding of electrochemical reactions and provide insight into the methods for improving lithium-ion battery performance.

Characterization of Surface Roughness and Inhomogeneity of Hot-Rolled Carbon Steels by Using Image Analysis Method and Electrochemical Impedance Spectroscopy

  • Pyun, Su-Il;Na, Kyung-Hwan;Go, Joo-Young;Park, Jin-Ju
    • Journal of the Korean Electrochemical Society
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    • v.6 no.3
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    • pp.217-223
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    • 2003
  • The present work is concerned with characterization of surface roughness and inhomogeneity of four kinds of hot-rolled carbon steels in terms of the fractal dimension and the depression parameter by using image analysis method and electrochemical impedance spectroscopy, respectively. From the analysis of the 3D AFM image, it is realized that all the hot-rolled steel surfaces show the self-affine fractal property. The values of the fractal dimension of the hot-rolled steels were determined by the analyses of the AFM images on the basis of both the perimeter-area method and the triangulation method. In addition, the Nyquist plots were found to be depressed from a perfect semicircle form. From the experimental findings, the changes in the values of the fractal dimension and the depression parameter with chemical composition have been discussed in terms of the change in the value of hardness of base steel.

Evaluation of the Corrosion Protective Property in Steel applying Spray Metal by using High-frequency Arc Metal Spray Method (고주파 아크 금속용사공법을 이용한 용사금속의 방식성능 평가)

  • Choe, Hong-Bok;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.94-95
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    • 2014
  • The purpose of this study is to evaluate the corrosion protective property of Al-Mg high-freqeuncy arc metal spray method in comparison to Zn-Sn and Zn-Al alloys by electrochemical method and CASS test. As a result, it appeared that Al-Mg alloy had very higher corrosion protective property through the electrochemical characteristic and the CASS test comparing with the other alloys.

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Nanowell Array based Sensor and Its Packaging

  • Lee, JuKyung;Akira, Tsuda;Jeong, Myung Yung;Lee, Hea Yeon
    • Journal of the Microelectronics and Packaging Society
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    • v.21 no.3
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    • pp.19-24
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    • 2014
  • This article reviews the recent progress in nanowell array biosensors that use the label-free detection protocol, and are detected in their natural forms. These nanowell array biosensors are fabricated by nanofabrication technologies that should be useful for developing highly sensitive and selective also reproducible biosensors. Moreover, electrochemical method was selected as analysis method that has high sensitivity compared with other analysis. Finally, highly sensitive nanobiosensor was achieved by combining nanofabrication technologies and classical electrochemical method. Many examples are mentioned about the sensing performance of nanowell array biosensors will be evaluated in terms of sensitivity and detection limit compared with other micro-sized electrode without nanowell array.