• Analytical Science and Technology
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• v.8 no.4
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• pp.583-590
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• 1995

Pitch-based mesophase carbon fibers prepared at different temperatures were heat-treated at temperatures lower than those of the preparation and the electrochemical Li doping/undoping characteristics were evaluated in relation to the data of IR, mass, etc. Presence of surface hydroxyls were confirmed by FTIR for lower temperature sample which showed poor anode characteristics. Upon oxidative heating, removal of surface hydroxyls took place, resulting in a remarkable improvement of the electrode characteristics. At the same time, surface roughening took place, which was confirmed by SEM and double layer capacity measurements. In situ mass spectra obesrved during the heat-treatments showed gas evolution of $H_2O$, CO, $CO_2$, $C_2H_4$, and/or $H_2$ depending on the conditions. These data together with those of weight loss and conductivity provided us a valuable information in regard to the evaluation of the electrochemical characteristics.

• Proceedings of the Korean Vacuum Society Conference
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• 2001.02a
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• pp.202-202
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• 2001

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.138.1-138
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• 1997

No Abstract, See Full Text

• Proceedings of the Korean Vacuum Society Conference
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• 2006.08a
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• pp.164-164
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• 2006

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.3
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• pp.208-215
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• 2009

PEMFC stack power output is needed to be around 100 kW to meet the requirements of automotive application and scaling-up the active area of the stack cells will allow a higher power. In the case of scaling-up the active area of cells, it is difficult to obtain uniform in-plane internal conditions such as temperature, relative humidity and stoichiometry of the feed gas. These ununiformity with the location in the cell would affect both the performance and durability of the stack, so it is important to understand phenomena in the cell for improving them. In this study, the current density, electrochemical resistance and performance distribution measurement was performed to understand the ununiformity in a single cell using in-situ method; (1) Current Density Distribution (CDD) Device and (2) Segmented Cell Fixture. The influence of location of feed gas on the performance of a single cell was experimentally measured and discussed by using a segmented single cell which was composed of 8 compartments. The correlation between the location and performance in a single cell was discussed by these two tools and it was extended between the local characterization and the durability in a MEA by comparing the used cell with a fresh one. It was also studied in terms of electrochemistry by Electrochemical Impedance Spectroscopy.

• Korean Journal of Materials Research
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• v.8 no.3
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• pp.263-267
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• 1998

In this study, we have fabricated in-situ multilayer $YBa_2Cu_3O_{7-\delta}$/$SrTiO_{3}$/$YBa_2Cu_3O_{7-\delta}$ ramp edge type junctions by using a metal mask and pulsed laser deposition method and studied the junction properties. The junctions showed RSJ-like I-V characteristics. The normal state junction resistance R, of $18 \omega$ was nearly constant with temperature. The dc-SQUID sensors fabricated with the junctions show a sensitivity that transfer function dV/$d\Phi$)~$22\mu$V/$\Phi_{0}$, indicating that the in-situ ramp edge type junction is potentially useful for sensor application.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.3
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• pp.199-208
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• 2012

To develop site characterization technologies for a radioactive waste disposal research in KAERI, the geological and hydrogeological investigations have been carried out since 1997. In 2006, the KURT (KAERI Underground Research Tunnel) was constructed to study a solute migration, a microbiology and an engineered barrier system as well as deeply to understand geological environments in in-situ condition. This study is performed as one of the site characterization works around KURT. Several investigations such as a lineament analysis, a borehole/tunnel survey, a geophyscial survey and logging in borehole, were used to construct the geological model. As a result, the geological model is constructed, which includes the lithological model and geo-structural model in this study. Moreover, from the results of the in-situ hydraulic tests, the hydrogeological properties of elements in geological model were evaluated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.26-30
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• 1995

We describe the preparation and characterization of epitaxial thin films made with high temperature superconductor, $YBa_2Cu_3O_{7-\delta}$. The influence of processing parameters for YBCO thin films on MgO substrates in-situ grown by the pulsed laser deposition, including parameters of a laser beam energy, oxygen pressure, substrate temperature, target-substrate dis-tance is discussed. The characteristics of YBCO thin films were analyzed by using XRD, R-T measurement, AFM, crosssectional TEM, and RBS. For examples of microwave device applications, The fabrication and characterization of the microstrip lowpass filter and bandpass filter are also presented.

• Journal of fish pathology
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• v.26 no.3
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• pp.163-171
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• 2013

Polymerase chain reaction (PCR) is the most rapid and widely used method to detect viral pathogens. However, this method does not provide histopathologic nature of the virus. In situ hybridization (ISH) with oligonucleotide probes is attractive because it is a rapid method for detection and identification of viral pathogens at sites of tissue infection. In order to understand the histopathologic characterictics of Red sea bream iridovirus (RSIV), viral-hemorrhagic septicemia (VHS) virus and viral nervous necrosis (VNN) virus to cultured olive flounder, we her applied ISH method to various kinds of olive flounder tissues with PCR-positive for these three viruses. We found that these viruses showed different tissue tropism and were detected from different cell types. Our results suggest that ISH is useful not only in rapid detection of viral pathogens but also in understanding the histopathologic characters of specific viral pathogens.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1169-1178
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• 1998

This study was performed to purify fig pectinesterase(F-PE) and characterize its in situ activity. Three kinds of F-PE were partially separated by using ammonium sulfate fractionation, Q-Sepharose column, CM-cation exchanger column chromatography, and HPLC. One of those was anionic protein and the others were cationic proteins. All of them had approximate molecular weight of 27,000 and lost rapidly their activity during storage. Therefore alternative crude enzyme was prepared by suspending the freeze dried and milled fig powder in 0.1 M NaCl at pH 7.5. F-PE had the optimum pH of 8.5, the optimum temperature of $50^{\circ}C$ with activation energy of 7,671 cal $mol^{-1}K^{-1}$ and stability up to $55^{\circ}C$ with 10 minutes heating. Optimum activity was obtained in $0.2{\sim}0.4$ M NaCl with optimum solubility at above 0.8 M NaCl.