• Journal of Power System Engineering
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• v.18 no.6
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• pp.40-44
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• 2014

The purpose of this paper is to investigate polarization characteristics of WC-based alloy coatings in alkaline solution. The coatings were fabricated with WC-CrC-Ni, WC-Co-Cr and WC-Co composite powders by HVOF process. Corrosion tests of coatings and substrate were carried out using potentiostat/galvanostat at solution with pH 8 and pH 13. Corrosion potential(Ecorr) and corrosion current density(Icorr) could be studied from polarization curve, and corrosion behavior was analyzed by SEM and EDS. WC-Co-Cr coating and WC-CrC-Ni coating showed more favorable anti-corrosion characteristics than WC-Co coating and substrate at solution with pH 8 and pH 13.

• Bulletin of the Korean Chemical Society
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• v.19 no.2
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• pp.160-164
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• 1998

The NADH-cytochrome b5 reductase (NCBR), a mitochondrial external electron carrier, was purified from bovine heart and turnip and their properties were examined. The mitochondrial outer membranes separated were subjected to NCBR isolation through DEAE-Cellulose ion exchange, DEAE-Sephadex gel chromatography, and hydroxyapatite adsorption chromatography. These processes yielded the purification folds of 88 and 42 and the recovery percentages of 0.2%, 5.67% for turnip and bovine heart, respectively. The molecular weight of the NCBR from the two sources was estimated to be 35,000 using SDS polyacrylamide gel electrophoresis. The Michaelis constant Km and maximum velocity Vmax were determined by measuring the NADH-ferricyanide redox system as well as the NADPH-ferricyanide redox system. The kinetics showed that both NCBRs had higher affinities for NADH than artificial electron-acceptor substrate ferricyanide. Although NADPH had a lower affinity for the enzymes than NADH, this study showed the 2'-phosphate dinucleotide could be used as a substrate.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.863-866
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• 2008

For the cost reduction in the fabrication of display panels, a reverse moving system was equipped to a compacted in-line wet etch/cleaning system. For the effect of the alternating movement of substrate on the wet etch process, ITO layers were etched in various moving modes of substrates and the results were compared and analyzed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.2
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• pp.39-46
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• 1982

A model of substrate removal by rotating discs has been developed for a better understanding of the process, and the performance of the system has been evaluated under steady and unsteady state. The model was constructed based upon mass transfer of the substrate from the bulk solution to the biofilm and a simultaneous removal of the substrate by the biomass. The model is composed of a few sets of differential equations representing mass balance within the elements of a liquid film and a biofilm, and in the bulk solution. Substrate removal efficiency of the process is largely dependent on a diffusion coefficient of the substrate within the biofilm and a maximum rate of substrate removal of the biomass. The efficiency is affected to a greater extent when the substrate concentration is low and the maximum substrate removal rate is high. The efficiency increases proportionally with increasing film depth when the biofilm is shallow, however, the rate of increase gradually decreases with an increase of the film depth. As the film reaches a limiting depth, the efficiency remains constant. Unlike the steady state, the effluent quality is affected by the tank volume under dynamic state. Increasing tank volume decreases peak concentration of the effluent under peak loading. Additional tank volume provides a buffer capacitya.gainst a peak loading and the holding tank behaves like an equalization tank.

• Proceedings of the Korean Vacuum Society Conference
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• 2008.08a
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• pp.313-313
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• 2008

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.105.1-105
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• 2002

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.43.2-44
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• 2002

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.4
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• pp.343-350
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• 2003

Circularly polarized-dual band antenna for GPS(Global Positioning System) and satellite radio system is developed and measured. Both circular polarization and overall antenna dimension reduction are achieved by placing a partially filled high-permittivity substrate under radiating edges. The bandwidth is also improved by choosing an optimal geometric configuration with a partially filled high permittivity substrate. The proposed antenna can be installed on moving vehicles or ships.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.439-440
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• 2008

Indium Zinc Tin Oxide (IZTO) thin films for transparent thin film transistor (TTFT) were deposited on glass substrate at room temperature by facing targets sputtering (FTS). The FTS system was designed to array two targets facing each other and forms the high- density plasma between. Two different kinds of targets were installed on FTS system. One is ITO ($In_2O_3$ 90wt.%, $SnO_2$ 10wt.%), the other is IZO($In_2O_3$ 90wt%, ZnO 10wt%). The conductive and optical properties of IZTO thin film is determined depending on variation of DC power and working pressure. Therefore, IZTO thin films were prepared with different DC power and working pressure. As-deposited IZTO thin films were investigated by a UV/VIS spectrometer, an X-ray diffractometer (XRD), a scanning electron microscopy (SEM), a Hall Effect measurement system. As a result, all IZTO thin films deposited on glass substrate showed over 80% of transmittance in visible range (400~800 nm) at $O_2$ gas flow rate. We could obtain IZTO thin films with the lowest resistivity $5.67\times10^{-4}$ [$\Omega{\cdot}cm$] at $O_2$ gas flow rate 0.4 [sccm).

• Journal of Information Display
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• v.8 no.3
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• pp.5-10
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• 2007

Twin target sputtering (TTS) system with a configuration of vertically parallel facing Al targets and a substrate holder perpendicular to the Al target plane has been designed to realize a direct Al cathode sputtering on organic light emitting diodes (OLEDs). The TTS system has a linear twin target gun with ladder type magnet array for effective and uniform confinement of high density plasma. It is shown that OLEDs with Al cathode deposited by the TTS show a relatvely lower leakage current density $({\sim}1{\times}10^{-5}mA/cm^2)$ at reverse bias of -6V, compared to that ($1{\times}10^{-2}{\sim}10^{-3}$ $mA/cm^2$ at -6V) of OLEDs with Al cathodes grown by conventional DC magnetron sputtering. In addition, it was found that Al cathode films prepared by TTS were amorphous structure with nanocrystallines due to low substrate temperature. This demonstrates that there is no plasma damage caused by the bombardment of energetic particles. This indicates that the TTS system with ladder type magnet array could be useful plasma damage free deposition technique for direct Al cathode sputtering on OLEDs or flexible OLEDs.