• Proceedings of the Korean Vacuum Society Conference
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• 1993.02a
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• pp.106-107
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• 1993

• Proceedings of the Korean Vacuum Society Conference
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• 2003.02a
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• pp.166-166
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• 2003

• Proceedings of the Korean Magnestics Society Conference
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• 1998.10a
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• pp.40-41
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• 1998

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.334-336
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• 1997

• Electrical & Electronic Materials
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• v.9 no.10
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• pp.991-1000
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• 1996

PbTiO$_{3}$-PbZrO$_{3}$-Pb(Ni$_{1}$3/Nb$_{2}$3/O$_{3}$) (PZT-PNN) thin films were prepared from corresponding metal organics partially stabilized with diethanolamine by the sol-gel spin coating method. Each mol ratio of PT:PZ:PNN solutions were #1(50:40:10), #2(50:30:20), #3(45:35:20), #4(40:40:20), #5(40:50:10), #6(35:45:20) and #7(30:50:20) respectively. The spin-coated PZT-PNN films were heat-treated at 350.deg. C for decomposition of residual organics, and were sintered from 450.deg. C to 750.deg. C for crystallization. The substrates, such as Pt and Pt/TiN/Ti/TiN/Si were used for the spin coating of PZT PNN films. The perovskite phase was observed in the PZT-PNN films heat-treated at 500.deg. C. The crystalline of the PZT-PNN films was optimized at the sintering of 700.deg. C. By the result of AES analysis, It is confirmed that the films of TiN/Ti/TiN was a good diffusion barrier and that co-diffusion into the each films was not observed.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1992.11a
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• pp.39-40
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• 1992

This paper dealt with the manufacturing of binary alloy catalyst and showed simple electrochemical method for determing catalytic activity of oxygen reduction in acid or alkaline electrolyte. The catalyst was prepared by impregnating transition metal salts on platinum or silver particles adsorbed before on carbon paper substrate. The electrochemical characteristics of the catalysts was investigated with carbon paper electrode or PTFE-boned porous electrode and then cathodic current densities and tafel slopes were compared. As a result, of all binary catalysts utilized in this work, Pt-Fe, Pt-Mo showed better oxygen reduction activity than pure platinum catalyst in acid electrolyte and Ag-Fe, Ag-Pt, and Ag-Ni-Bi-Ti catalyst did than pure silver catalyst in alkaline electrolyte. The current density of Pt-Fe electrode in acid electrolyte was one and half times higher than that of Pt electrode(~500mA/$\textrm{cm}^2$ at 0.7VvsNHE).

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.3
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• pp.193-200
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• 2019

$RuO_2$, $PtO_2$, and various $(Ru,Pt)O_2$ colloidal solution were prepared using modified Watanabe method. Electrodes were manufactured by dipping of Ni mesh into the colloidal solution. Manufactured electrodes were characterized by XRD, SEM, and EDS. $(Ru,Pt)O_2$ electrodes showed $RuO_2$ crystal structure and high roughness. The hydrogen evolution reaction (HER) activities were evaluated by Linear Sweep Voltammetry. 1Ru2Pt electrode showed similar activity with commercial electrode, HER potentials are -0.9 V for both.

• Journal of the Korean Electrochemical Society
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• v.17 no.3
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• pp.164-171
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• 2014

A highly sensitive and selective non-enzymatic glucose sensor has gained great attention because of simple signal transformation, low-cost, easily handling, and confirming the blood glucose as the representative technology. Until now, glucose sensor has been developed by the immobilization of glucose oxidase (GOx) on the surface of electrodes. However although GOx is quite stable compared with other enzymes, the enzyme-based biosensors are still impacted by various environment factors such as temperature, pH value, humidity, and toxic chemicals. Non-enzymatic sensor for direct detecting glucose is an attractive alternative device to overcome the above drawbacks of enzymatic sensor. Many efforts have been tried for the development of non-enzymatic sensors using various transition metals (Pt, Au, Cu, Ni, etc.), metal alloys (Pt-Pb, Pt-Au, Ni-Pd, etc.), metal oxides, carbon nanotubes and graphene. In this paper, we show that Ni-based nano-particles (NiNPs) exhibit remarkably catalyzing capability for glucose originating from the redox couple of $Ni(OH)_2/NiOOH$ on the surface of ITO electrode in alkaline medium. But, these non-enzymatic sensors are nonselective toward oxidizable species such as ascorbic acid the physiological fluid. So, the anionic polymer was coated on NiNPs electrode preventing the interferences. The oxidation of glucose was highly catalyzed by NiNPs. The catalytically anodic currents were linearly increased in proportion to the glucose concentration over the 0~6.15 mM range at 650 mV versus Ag/AgCl.

• Journal of the Optical Society of Korea
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• v.12 no.2
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• pp.112-117
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• 2008

Single-mode propagation conditions of X-ray waveguides are investigated by numerical calculations in order to understand the importance of waveguide design parameters, such as core thickness and the optical constants of waveguide materials, on the transmission and coherence properties of the waveguide. The simulation code for mode analyzing is developed based on a numerical solution of the parabolic wave equation. The initial boundary value problem is solved numerically using a finite-difference scheme based on the Crank-Nicolson scheme. The E-field intensities in a core layer are calculated at an X-ray energy of 8.0 keV for air and beryllium(Be) core waveguides with different cladding layers such as Pt, Au, W, Ni and Si to determine the dependence on waveguide materials. The highest E-field intensity radiated at the exit of the waveguide is obtained from the Pt cladded beryllium core with a thickness of 20 nm. However, the intensity from the air core waveguide with Pt cladding reaches 64% of the Be-Pt waveguide. The dependence on the core thickness, which is the major parameter used to generate a single mode in the waveguide, is investigated for the air-Pt, and Be-Pt waveguides at an X-ray energy of 8.0 keV. The mode profiles at the exit are shown for the single mode at a thickness of up to 20 nm for the air-Pt and the Be-Pt waveguides.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.401-410
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• 2016

The $Pt-Sn/Al_2O_3$ catalysts mixed with metal oxides for propane dehydrogenation were studied. $Cu-Mn/{\gamma}-Al_2O_3$, $Ni-Mn/{\gamma}-Al_2O_3$, $Cu/{\alpha}-Al_2O_3$ was prepared and mixed with $Pt-Sn/Al_2O_3$ to measure the activity for propane dehydrogenation. As standard sample, $Pt-Sn/Al_2O_3$ catalyst mixed with glassbead was adopted. In the case of catalytic activity test after non-reductive pretreatment of catalyst and metal oxide, $Pt-Sn/Al_2O_3$ mixed with $Cu-Mn/{\gamma}-Al_2O_3$ showed higher conversion of 15% and similar selectivity at $576.5^{\circ}C$, compared to conversion of 8% in standard sample. In the case of catalytic activity test after reductive pretreatment of catalyst and metal oxde, $Cu/{\alpha}-Al_2O_3$ showed higer yield than standard sample. But, increase of yield of most of samples after reductive pretreatment was not significant, so it was found that lattice oxygen of $Cu-Mn/{\gamma}-Al_2O_3$ is effective to propane dehydrogenation.