• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.135.2-135.2
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• 2010

Carbon nanotube(CNT) has been spotlighted as a promising candidate for catalyst support material for PEMFC (proton exchange membrane fuel cell). The considerable properties of CNT include high surface area, outstanding thermal, electrical conductivity and mechanical stability. In this study, to fully utilize the properties of CNTs, we prepared directly oriented CNT on carbon paper as a catalyst support in the cathode electrode. The CNT layer was prepared by a chemical vapor deposition(CVD) process. And the Pt particles were deposited on the CNT oriented carbon paper by impregnation and eletro-deposition method. The potential advantages of directly oriented CNT on carbon paper can include improved thermal and charge transfer through direct contact between the electrolyte and the electrode and enhanced exposure of Pt catalyst sites during the reaction.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.53-58
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• 2002

A method for the determination of lead(II) ion using a nafion-EDTA(ethylene diamine tetraacetic acid)-glycerol modified glassy carbon electrode was proposed. Lead(II) ion is accumulated at the electrode by complexation and electrostatic attraction with nafion-EDTA-glycerol and detected at -0.560$\pm$0.015V (vs. Ag/AgCl) by differential pulse voltammetry. For the determination of lead(II) ion, a standard calibration curve if obtained from 10$^{-9}$ M lead(II) ion to 10$^{-7}$ M, and the detection limit(3s) is as low as 5.0$\times$10$^{-10}$ M.

• Journal of the Korean Ceramic Society
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• v.45 no.8
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• pp.482-485
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• 2008

Composite electrode consisting of carbon nanofiber (CNF) and cobalt oxide was prepared for supercapacitor electrode, and its electrochemical property was investigated by means of cyclic voltammetry. Cyclic voltammetric results for the composite electrode showed it had specific capacitance value of 420 F/g at 5 mV/s, which was higher than capacitance value of 180 F/g for the bare CNF. It is concluded that the capacitive property of CNF can be improved by coating cobalt oxide on it to increase the surface area of cobalt oxide.

• Journal of the Korean Ceramic Society
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• v.45 no.8
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• pp.493-496
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• 2008

Composite electrodes consisting of $CoMnO_2$ and carbon nanofibers(vapor grown carbon nanofiber, VGCF) with high electrical conducivity($CoMnO_2$/VGCF) were prepared on a porous nickel foam substrate as a current collector and their supercapacitive properties were investigated using cyclic voltammetry in 1 M KOH aqueous solution. The $CoMnO_2$/VGCF electrode exhibited high specific capacitance value of 630 F/g at 5 mV/s and excellent capacitance retention of 95% after $10^4$ cycles, indicating that the used VGCF played the important roles in reducing the interfacial resistance in the composite electrode to improve supercapacitive performance.

• Analytical Science and Technology
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• v.12 no.2
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• pp.171-175
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• 1999

Carbon paste electrodes, modified with podands containing more than two sulfur atoms, have been employed for the voltammetric determination of Ag(I) ion from aqueous solution. The voltammetric response was characterized with respect to paste composition, preconcentration method, kind of anion, variation of pH, Ag(I) ion concentration, and possible interferences. Linear calibration curves were obtained for Ag(I) ion concentration ranging from $1.0{\times}10^{-6}$ to $9.0{\times}10^{-5}M$, and detection limit was $5.0{\times}10^{-7}M$.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.12
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• pp.164-170
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• 2010

For the surge currents like lightning or ground fault currents containing high frequency components which cause the electromagnetic interferences for the electronic devices and communication equipment, the grounding impedances give the significantly composite characteristics which are dependent on the frequency of surge currents. In this paper, the analytical model and method for determining the optimal length of the newly developed coaxial type carbon ground electrode which has a little fluctuation in grounding impedance with frequency. The length of minimizing the fluctuation of grounding impedance by changing frequency from 100[Hz] to 1[MHz] was determined, and the validity of this proposed method was confirmed by comparing with the simulated and measured data.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.392-394
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• 2009

Direct Carbon Fuel Cells (DCFCs) generates electricity directly converting the chemical energy in coal. In the present study, effects of anode and current collector materials on the power density of DCFC are investigated experimentally. The adopted DCFC system is combined type of solid oxide fuel cells (SOFC) and molten carbonate fuel cells (MCFC) with the use of a liquid-molten salt anode and a solid oxide electrolyte, proposed by SRI. Power densities of 25 mm button cells with various combination of anode materials and current collector materials are measured.

• Analytical Science and Technology
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• v.15 no.1
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• pp.91-95
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• 2002

Carbon paste electrodes, modified with 5,6,14,15-dibenzo-1,4-dioxa-8,12-diazacyclopentadeca-5,14-diene containing different ligating atoms of oxygen and nitrogen, have been employed for the voltammetric determination of Ag(I) ion from aqueous solution. The voltammetric response was characterized with respect to paste composition, preconcentration method, kind of anion, variation of pH, Ag(I) ion concentration, and possible interferences. Linear calibration curves were obtained for Ag(I) ion concentration ranging from $3.0{\times}10^{-6}M$ to $8.0{\times}10^{-5}M$, and detection limit was $8.5{\times}10^{-7}M$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.114-115
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• 2006

In the present study we investigated effects by changing binder contents m the carbon counter electrode for dye-sensitized solar cells. Binder contents changed for 6 wt%, 7 wt%, 8 wt% before making carbon electrode. In the result of the measurement the specific resistance for 6 wt% was lowest among others And the surface of the carbon electrode which was measured by SEM was best m the 6 wt"%. The electrode properties be showing in an experiment were due to increment of surface roughness that appeared the carbon electrode, which decreased internal surface area.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.04b
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• pp.60-63
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• 2004

Recently, carbon nanotubes(CNTs) have been demonstrated to possess remarkable mechanical and electronic properties, in particular, for field emission applications. Its high aspect ratio and extremely small diameter, hollowness, together with high mechanical strength and high chemical stability, are advantages for use in field emitter. In this paper, we demonstrate electrical discharge properties from carbon nanotube cathode electrodes to use as an emitter electrode of vacuum gauges. Vertically aligned $2{\times}2mm^2$ CNT arrays on the silicon substrate were synthesized by the thermal CVD method on Fe catalytic metal, and a glass patterning by the sand blast method and the silicon/glass anodic bonding processes were applied to make samples with 2 electrodes. The field emission was examined under the vacuum range of $10^{-3}$ Torr.