• Journal of the Korean Electrochemical Society
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• v.16 no.3
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• pp.145-150
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• 2013

In this study, the electrochemical investigation of various electrodes for reverse electrodialysis using potassium ferrocyanide and potassium ferricyanide as a redox system was carried out. Cyclic voltammetry was the employed method for this electrochemical study. From the results of cyclic voltammograms for various electrode materials, i.e., Au, Vulcan supported Pt, activated carbon, carbon nanofiber, Vulcan, the Vulcan electrode showed the lowest overpotential, but the Pt electrode having slightly higher overpotential obtained slightly higher anodic and cathodic current densities for the $Fe(CN)_6{^{4-}}/Fe(CN)_6{^{3-}}$ redox couple. The cyclic voltammograms for the Vulcan electrode confirmed very good electrochemical reversibility and kinetic behavior. As a result, among the electrode materials, the Vulcan electrode is the most promising electrode material for reverse electrodialysis.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.2
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• pp.219-229
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• 2012

In the course of feasibility study the necessity of implementing electrochemical methods as an inline metrology technique to characterize semiconductor nano structures for a Deep Trench Dynamic Random Access Memory (DT-DRAM) (e.g. ultra shallow junctions USJ) was discussed. Hereby, the state of the art semiconductor technology on the advantages and disadvantages of the most recently used analytical techniques for characterization of nano electronic devices are mentioned. Various electrochemical methods, their measure relationship and correlations to physical quantities are explained. The most important issue of this paper is to prove the novel usefulness of the electrochemical micro cell in the semiconductor industry.

• Journal of Electrochemical Science and Technology
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• v.6 no.3
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• pp.81-87
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• 2015

This study introduces a facile strategy to prepare metal oxide/conducting polymer nanocomposites that may have promising applications in energy storage devices. Ploy aniline/nano wire manganese dioxide (PANI/NwMnO₂) was synthesized by cyclic voltammetry on glassy carbon electrode. Morphology and structure of the composite, pure PANI, MnO₂ nanowires were fully characterized using XRD and SEM analysis. Electrochemical studies shows excellent synergistic effect between PANI and MnO₂ nanowires which results in its capacitance increase and cycle stability against PANI electrode. Specific capacitances of PANI/NwMnO₂ and PANI were 456 and 190 F/g respectively. The electrochemical performance of electrodes studied using cyclic voltammetry, Galvanostatic charge/discharge and impedance spectroscopy.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.1
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• pp.43-49
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• 2003

In this study, micro electrochemical machining method was introduced for accomplishment the fabrication technology of functional parts and smart structures using the Ni-Ti shape memory alloy. From the experimental result, the micro part which has very fine surface could be achieved by use of micro electrochemical process with point electrode method. Concretely, the optimal performance of micro electrochemical process in Ni-Ti SMA was obtained at the condition of approximately 100% of current efficiency and high frequency pulse current. That is, much finer surface integrity and shape memory effect can be obtained at the same condition mentioned above.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.356-361
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• 2003

Electrochemical micromachining which is not normally considered as a precision process is presented in this paper. The application of voltage Pulses between a tool electrode and a workpiece in an electrochemical environment allows the three-dimensional machining of conducting materials with micrometer precision. In this paper tool-electrodes($5\mu\textrm{m}$ in diameter, 1mm in length) are developed by electrochemical micromaching and micro holes are manufactured using this tool-electrodes we developed already. Micro holes are achieved the accuracy below $50\mu\textrm{m}$ in diameter using ultrashort voltage pulses(0.1-5$\mu\textrm{s}$).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.214-217
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• 2002

Micro Surface Electrochemical Machining has traditionally been used in highly specialized fields such as those of the aerospace and defense industries. It is now increasingly being applied in other industries where parts with difficult-to-cut material, complex geometry and tribology such as compute. hard disk drive(HDD) are required. Pulse Electrochemical Micro-machining provides an economical and effective method for machining high strength, high tension, heat-resistant materials into complex shapes such as turbine blades of titanium and aluminum alloys. Usually aluminum alloys are used bearings to hard disk drive in computer. In order to apply aluminum alloys to bearing used in hard disk drive, this paper presents the characteristics of Micro Surface Electrochemical machining for aluminum alloy.

• Journal of Sensor Science and Technology
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• v.21 no.5
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• pp.374-378
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• 2012

Biofouling causes many problem in industrial processes, medical health industries, water utilities and our daily life. So detecting formation of biofilm on the surface of medical appliance, water pipe and industrial utility is highly important to prevent the problem caused by biofouling. In this study, we suggest an electrochemical sensor for detecting biofilm. We fabricated the electrochemical sensor in MEMS process and cultivated two different kinds of Pseudomonas aeruginosa RpoN type and Wild type on the surface of electrochemical sensor. Each group of Pseudomonas aeruginosa was cultivated according to the hours of 2, 4, 6, 8, 12 and 24. Then we investigated changes in degree of biofilm cultivation using cyclic voltammetry. As a result, it was observed that peak of the cyclic voltammetry curve is increased according as the biofilm growth on the surface of electrochemical sensor. Also we can discern between Pseudomonas aeruginosa RpoN type and Wild type.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.147-148
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• 2018

In order to compare the electrochemical performance with that of Calomel Electrode, MnO2 solid-state-electrode was fabricated and its potential and impedance were measured in chloride aqueous solution. As a result, the SCPS without chloride ions showed a potential of -200 mV or more and an impedance over 2000 Ωcm, but the potential below -600 mV and the impedance below -200 Ωcm showed as the chloride concentration in the solution increased. It is considered electrochemical studies on the corrosion of rebar are necessary for the MOE, which shows the same tendency as SCE and exhibits electrochemical performance, over the Mortar level in the future.

• Journal of the Korean Electrochemical Society
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• v.5 no.4
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• pp.197-201
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• 2002

In this study, a gel polymer electrolyte was prepared from urethane acrylate and its electrochemical performances were evaluated. And, $LiCoO_2/GPE/graphite$ cells were prepared and their performances depending on discharge currents and temperatures were evaluated. The precursor containing $5 vol\%$ curable mixture had a low viscosity relatively. Ionic conductivity of the gel polymer electrolyte at room temperature and $-20^{\circ}C$ was ca. $5.9\times10^{-3}S{\cdot}cm^{-1}\;and\;1.7\times10^{-3}S{\cdot}cm^{-1}$, respectively. GPE showed electrochemical stability up to potential of 4.5V vs. $Li/Li^+.LiCoO_2/GPE/graphite$ cell showed a good high-rate and a low-temperature performance.

• Journal of the Korean Electrochemical Society
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• v.7 no.2
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• pp.80-82
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• 2004

The a.c. technique is employed to evaluate electrochemical characteristics of Naphthalie-1,4,5,8-tetracarboxylic acid bisanilide (NTB). The measurements were carried out in dry and pure propionitrle (PCN) and acetonitrile(CAN) at the hanging mercury drop electrode [HMDE). An A.C. phase sensitive detector using computer controlled lock-in amplifier was employed. Primary goal of this report, was to establish on a firm the rare behavior of the phase angle associated with a.c. polarograms of the compound. Although, not an initial goal of this study, the electron transfer rate parameters attending the electroreduction of the compound under investigation were determined. This because the results shed some light on the electrokinetics in aprotic solvent which until recently negligible data were available. Experimental Results and comparison of data obtained are reported. The good precision of the method makes it suitable for studying electrochemical data with unusual behavior at electrodes in non aqueous media.