• Proceedings of the Optical Society of Korea Conference
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• 1999.08a
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• pp.80-81
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• 1999

• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.118-120
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• 2001

The $0.96MgTiO_3-0.04SrTiO_3+xLa(0{\sim}1.0wt%)$ ceramics were prepared by conventional mixed oxide method. The structural properties of $0.96MgTiO_3-0.04SrTiO_3+xLa(0{\sim}1.0wt%)$ ceramics with sintering temperature were investigated by the XRD and SEM. From the X-ray diffraction patterns, it was found that the perovskite $SrTiO_3$ and ilmenite $MgTiO_3$ structures were coexisted in the $0.96MgTiO_3-0.04SrTiO_3$ ceramics. The second phase of $Sr_{0.5}LaTi_2O_6$ was shown with addition of the $La_2O_3$. The dielectric constant(${\varepsilon}_r$), $Q{\times}f$ value and the temperature coefficient of the $0.96MgTiO_3-0.04SrTiO_3+0.2La$ ceramics were 21. 41, 39991, $-3.3ppm/^{\circ}C$, respectively.

• Journal of the Korean Ceramic Society
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• v.44 no.7
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• pp.387-392
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• 2007

Thermal conductivities in $La_2Ce_2O_7-Gd_2Ce_2O_7-Y_2Ce_2O_7$ ternary system have been investigated. Pyrochlore phases formed at all ternary compositions and their sinterbilities were decreased with La addition. Thermal conductivities showed a minimum value at $La_2Ce_2O_7$ with moderate increases as $Y^{3+}$ and $Gd^{3+}$ ions replaced $La^{3+}$. Thermal expansion anomaly observed in $La_2Ce_2O_7$, which might be detrimental to TBC application, were suppressed by $Y^{3+}$ and $Gd^{3+}$ additions, with resultant thermal conductivities, $1.3{\sim}1.5 W/mK$ at $1000^{\circ}C$.

• Journal of Life Science
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• v.14 no.4
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• pp.567-572
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• 2004

This study was carried out to investigate the affects on antimicrobial and cytotoxicity of red cabbage (Brassica oleracea L.,BO). In the paper disc test, antimicrobial activity of BO fractions was increased in proportion to its concentration. Among the various solvent fractions of methanol extract (BOM) of BO, the ethylacetate partition layer (BOMEA) showed the strongest antimicrobial activity We also determined the cytotoxicity and Quinone Reductase induced effect of BO extract and fractions on human cancer cells. The cytotoxicity of BO fractions on HepG2, HeLa and MCF-7 cells was evaluated by MTT assay. The BOMEE and BOMEA showed strong cytotoxic effects on all cancer cell lines we used. The quinone reductase induced effect of BO fractions on HepG2 cells, the hexane partition layer (BOMH) at a dose of 200 $\mu{g}$/ml was 2.88 times more effective compared to the control values of 1.0.

• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.306-311
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• 2016

Li-air batteries have received much attention due to their superior theoretical energy density. However, their sluggish kinetics on the cathode side is considered the main barrier to high performance. The rational design of electrode catalysts with high activity is therefore an important challenge. To solve this issue, we performed density functional theory (DFT) calculations to analyze the adsorption behavior of the $LiO_2$ molecule, which is considered to be a key intermediate in both the Li-oxygen reduction reaction (ORR) and the evolution reaction (OER). Specifically, to use the activity descriptor approach, the $LiO_2$ adsorption energy, which has previously been demonstrated to be a reliable descriptor of the cathode reaction in Li-air batteries, was calculated on $LaB_{1-x}B^{\prime}_xO_3$(001) (B, B' = Mn, Fe, Co, and Ni, x = 0.0, 0.5). Our fast screening results showed that $LaMnO_3$, $LaMn_{0.5}Fe_{0.5}O_3$, or $LaFeO_3$ would be good candidate catalysts. We believe that our results will provide a way to more efficiently develop new cathode materials for Li-air batteries.

• Proceedings of the Korean Magnestics Society Conference
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• 2000.09a
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• pp.459-460
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• 2000

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.337-337
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• 2003

• Proceedings of the Korean Magnestics Society Conference
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• 2006.06a
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• pp.68-69
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• 2006

• The KSFM Journal of Fluid Machinery
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• v.7 no.2 s.23
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• pp.90-101
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• 2004

• Proceedings of the Korean Magnestics Society Conference
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• 2015.05a
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• pp.155-155
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• 2015