• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.569-572
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• 2001

Selective, highly stable determination of epinephrine(adrenalin) was achieved in cyclic voltammetric measurement carried out at electrochemically treated conductive boron-doped diamond electrode. Boron-doped diamond electrodes were prepared on single crystal Si wafers by microwave plasma chemical vapor deposition and B$_2$O$_3$ was dissolved in acetone/methanol(1:1) mixture solution so that the B/C weight ratio ca. 10$^3$ppm.. Epinephrine is a kind of catecholamines, which secreted from adrenal marrow cells. The serious problem to detection of epinephrine is the interference phenomena of electroactive constituent, including AA. In this study, electrochemical treatment of BDD was carried out to discriminate between epinephrine and AA responses. Experimental results showed that the peak potential of AA oxidation shift to the positive direction and the oxidation peak of epinephrine was unchanged. The effect of electrochemical treatment was maintained up to 40hrs.

• Journal of Korean Society on Water Environment
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• v.27 no.5
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• pp.617-624
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• 2011

In order to confirm the creation of the OH radical which influences to RNO bleaching processes, it experimented using laboratory reactor of dielectric barrier discharge plasma (DBDP). The experiments performed in about 4 kind process variables (diameter of ground electrode, diameter of discharge electrode, diameter of quartz tube and effect of air flow rate) which influence to process. In order to examine optimum conditions of design factors as shown in Box-Behnken experiment design, ANOVA analysis was conducted against four factors. The actual RNO removal at optimized conditions under real design constraints were obtained, confirming Box-Behnken results. Optimized conditions under real design constraints were obtained for the highest desirability at 1, 1 mm diameter of ground and discharge electrode, 6 mm diameter of quartz tube and 5.05 L/min air flow rate, respectively.

• Bulletin of the Korean Chemical Society
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• v.16 no.3
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• pp.221-226
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• 1995

A method for determining nitrate in post treatment chromium plating solutions with PVC-based nitrate-selective electrodes is described. PVC-based nitrate-selective membranes which contain TDMANO3 ion-exchanger in PVC/NPOE, PVC/DOA or PVC/DBP matrices, and a commercially available Corning electrode (No. 476134) have been compared in respect of their detection limits, response slopes, selectivities at various pHs, and dynamic response to the hydrochromate ion in basic condition. The PVC/DBP/TDMANO3 membrane electrode was chosen as the ISE detector for the determination of nitrate in the presence of hydrochromate interference. The amount of nitrate in real post treatment chromium plating solution could be determined successfully with this electrode in both static and flow-injection measurements when the sample was properly diluted with an alkaline buffer.

• Journal of Hydrogen and New Energy
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• v.10 no.3
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• pp.159-170
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• 1999

Recently Ni/MH secondary battery have been studied very extensively because of containing no pollutants as well as superior performance. However comparing to widely studying high capacity of hydrogen storage alloys electrode, the capacity of Ni electrode is inferior. Using for high capacity Ni/MH battery as a anodic materials, the study about high capacity Ni electrode is necessary. To making high capacity Ni electrode, active materials were impregnated in various polarization impregnation conditions. Plaque, milling for 6hr and sintered at $800^{\circ}C$, indicated porosity over 80%, and porosity were increased with proper condition electrochemical etching treatment. Proper impregnation condition was 40~80mA/cm, polarizing time was 5~10min.

• Journal of the Korean Ceramic Society
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• v.33 no.11
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• pp.1231-1236
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• 1996

The electrode resistance of semiconducting PTC BaTiO3 ceramic material was studied in some detail. Comme-rical In-Ag paste In-Ga alloy and electroless plated Ni as well as evaporated Al were chosen as electrode. The contact resistance of electroded samples were measured by both dc resistivity and ac impedance analysis. The aging effect on contact resistance under cyclic loading from -1$0^{\circ}C$ to 85$^{\circ}C$ was also monitored for the prolonged period of time. In case of Al electroded samples the heat treatment and protective coating had effects on the stability against contact resistance degradation. It was also found that the samples with commercial In-Ag paste and electroless plated Ni electrode had good properties of contact resistance against aging.

• Journal of Hydrogen and New Energy
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• v.32 no.6
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• pp.612-617
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• 2021

In the case of a metal sulfide electrode, it is used as an anode or cathode active material in a lithium battery. The reason is that the voltage exists between 0.8 and 2.0 V via lithium electrode and the discharge and charge capacity is high. In order to manufacture nickel sulfide for electrode, which are widely used, nano-nickel powder was sulfided using ammonium polysulfide, and single-phase NiS electrodes were manufactured through heat treatment. The prepared NiS electrode had a high initial capacity of 500 mAh/g or more, and was stabilized after 20 cycles to maintain a capacity of 400 mAh/g or more until 100 cycles.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.417-423
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• 2019

A new wastewater treatment system was developed to remove nitrate nitrogen and phosphorus in synthetic wastewater through electrochemical treatment. Higher removal efficiencies of nitrate nitrogen were obtained as the current density increased. Higher nitrate removal efficiencies were obtained when the switching interval was 1 min. The total phosphorus removal rate according to the current density was found to be over 90% without being greatly affected by the change in current density and interval, and the total removal rate increased with increasing switching time (1 min interval). On the other hand, COD was not treated by electrochemical treatment, but rather increased as the electrode eluted. Also, the consumption rate of the electrode was smaller as the switching interval was shorter. Finally, removal efficiencies of 98.1% of nitrate and 90% of phosphorus were obtained through electrochemical treatment (current density $50mA/cm^2$, switching interval 1 min, flow rate 540 mL/min).

• Journal of the Korean Society for Heat Treatment
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• v.23 no.3
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• pp.137-141
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• 2010

The Co-Cr alloys have clinical histories in dental and orthopaedic implants, and recently in cardiovascular stent applications because the alloys exhibit a high elastic modulus and radiopacity. In order to improve mechanical property of the Co-Cr alloys, electropolishing is employed as the final process. Electropolishing, an anodic dissolution process in the transpassive state, is sensitively affected by process conditions such as current density, machining time, electrode gap. In this study, the effect of heat treatment conditions on surface roughness and inclusion analysis is investigated in Co-Cr alloy (L605). The most smooth surface of Co-Cr alloy is obtained when electropolishing is performed at 15-20 V for 15-30 sec with a electrode gap of 3.5 mm.

• Transactions on Electrical and Electronic Materials
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• v.3 no.4
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• pp.27-31
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• 2002

Thin film diode with reliable interfacial structure was fabricated by using multi-step anodic oxidation. The thickness of the oxide layer was preciously controlled with anodic voltage. Also, interfacial structure between oxide layer and top electrode was improved by applying post heat-treatment. The thin film diode showed symmetric and stable I-V characteristics after the post heat-treatment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.3 no.2
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• pp.77-84
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• 1997

For the effective treatment of shipboard sewage continuously, a non-diaphragm electrolytic treatment device using DSA type insoluble electrode, Ti/IrO2, anode and H-C metal cathode, was studied. The most effective electrolytic conditions were obtained when cell clearance, 6mm, pH 5-6 and the concentration of seawater, more than 20% as batch test results. The COD removal rate was varied in logarithmic function, showed as C=Coe-KE and the required current was E = A/QCo [A.min/mgCOD]. When the COD removal effeciency was more than 90%, the electrolytic reaction constant was 0.02.