• Transactions of the Korean hydrogen and new energy society
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• v.18 no.1
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• pp.32-39
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• 2007

CO oxidation and selective CO oxidation of $La_xCe_{1-x}Co_yCu_{1-y}O_{3-{\alpha}}$ perovskite(x=1, 0.9, 0.7. 0.5; y=1, 0.9, 0.7, 0.5) were investigated. For CO oxidation, catalytic activities were studied according to different preparation conditions such as pH and calcination temperature. The influence of the change of the $O_2$ concentration for selective CO oxidation was studied, too. The substitution of Ce for La improved the catalytic activity for CO oxidation and selective CO oxidation and best activity was observed for $La_{0.7}Ce_{0.3}CoO_3$ prepared at pH 11 and calcined at $600^{\circ}C$. The temperature of 90% CO conversion for CO oxidation using $La_{0.7}Ce_{0.3}CoO_3$ was $230^{\circ}C$. In contrast to the enhancement effect by Ce substitution, the partial substitution of Cu for Co in $LaCo_yCu_{1-y}O_{3-{\alpha}}$ decreased catalytic activities for CO oxidation reaction compared to that using $LaCoO_3$. For selective CO oxidation, the best CO conversion was 66% at $230^{\circ}C$ for $La_{0.7}Ce_{0.3}CoO_3$. The CO conversion of $La_{0.7}Ce_{0.3}CoO_3$ was greatly increased from 66% to 91% as increasing $O_2$ concentration from 1% to 2%.

• Korean Journal of Acupuncture
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• v.22 no.3
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• pp.137-156
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• 2005

Objectives : Cnidium officinale(CO) has been used for medication for stroke in the Oriental Medicine. So this study was planned to investigate the effects of CO on the focal ischemia-induced by Middle Cerebral Artery Occlusion(MCAO) in rats Materials and methods : The focal ischemia was induced by MCAO. CO extracts through oral administration and herbal acupuncture at GB2l was carried out during 3 weeks after focal ischemia-induced. Eight-arm radial maze was used for the behavioral task. For the neuroprotective effect of CO, we investigated AchE, ChAT, and NGF-expression by immnohistochemical method. Results : The error rate in the eight-arm radial maze task was significantly decreased in normal group compared to control group on 1-6days, OA-CO1(CO oral administration, 0.8g/kg) group on 1-6days, OA-CO2(CO oral administration, 1.6g/kg) group on 1-3,5,6days, HA-CO1(CO herbal acupuncture, 0.016g/kg) group on 2,3,6days, HA-CO2(CO herbal acupuncture, 0.008g/kg) group on 1-3,5,6days. The rate of correct choice was significantly increased in OA-CO1, HA-CO2. The density of neurons in the hippocampal CA1 was the most increased in OA-CO1, HA-CO1, HA-CO2. The density of ChAT in the hippocampal CA1 was increased in OA-CO1, HA-CO2. The density of ChAT in the hippocampal CA1 was significantly increased in OA-CO1, HA-CO2. The density of NGE in the hippocampal CAI was significantly increased in OA-CO1, OA-CO2, HA-CO2. Conclusions : These results suggest that CO oral administration with 0.8g/kg and CO herbal acupuncture with 0.008g/kg might be used as a regulator of cell death of cholinergic system induced by stroke.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.318-319
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• 2005

본 연구에서는 $LiCoO_2/LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ 혼합 정극활물질로 사용하여 전극을 제작하고 성능을 평가하였다. $LiCoO_2/LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$와 $LiCoO_2$의 혼합비에 따른 충방전 거동 및 임피던스 변화를 측정하였다. 각 조성에서의 초기용량은 160 ~ 170 mAh/g 정도였으며, $LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$의 첨가 비율이 증가함에 따라 비용량이 증가하였으나 고율에서의 방전용량은 낮았다.

• Journal of the Korean Magnetics Society
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• v.3 no.1
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• pp.1-6
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• 1993

Electronic and magnetic proper tis of the rare-earth transition metal compound, $LaCo_{13}$, are investigated by performing self-consistent local density functional LMTO (linearized muffin-tin orbital) band structure calculations for both paramagnetic and ferromagnetic phases of $LaCo_{13}$. The calculated magnetic moments for the two types of Co atoms, Co I and Co II, are 1.34 and $1.65{\mu}_{B}$, respectively. The average magnetic moment of Co atoms in the ferromagnetic phase of $LaCo_{13}$ is estimated to be $1.60{\mu}_{B}$, which is in fairly good agreement with the experimental values, $1.56~1.68{\mu}_{B}$.

• Journal of the Korean Magnetics Society
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• v.25 no.5
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• pp.139-143
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• 2015

The surface magnetism of the CsCl structured Co binary compounds, CoX (X = Ti, V, Nb) (001) surface was studied with the calculated electronic structure data obtained by the full-potential linearized augmented plane-wave (FLAPW) method. The magnetic moment of the surface Co atom of the Co-terminated CoTi(001) system was $1.19{\mu}_B$, which is enhanced compared with that of the Co atom in the center layer. The magnetic moment of the surface V atom in the V terminated the CoV(001) system was $1.64{\mu}_B$, which is more than twice of the center layered V atom. The magnetic moment of surface Co atom in the Co terminated CoV(001) system has the value of $1.34{\mu}_B$, little bit smaller than the bulk value. The magnetism was disappeared in the Co terminated CoNb(001) system, and the magnetic moment of the surface Nb atom in the Nb terminated CoNb(001) system was $0.26{\mu}_B$ which is little bit decreased compared to the center layer value.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.198-201
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• 2006

The optimization of poly-Si TFT process on metal foil for UTL AMOLED was systematically investigated. The improvement in device performance of poly-Si TFT on metal foil was achieved by optimizing the dopant activation condition and gate dielectric structure. Hence, the world first flexible full color 5.6-inch AMOLED with top emission mode on poly-Si TFT stainless steel foil is demonstrated.

• Polymer(Korea)
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• v.35 no.6
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• pp.586-592
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• 2011

In this study, we synthesized vinylbenzyl chloride-co-styrene-co hydroxyethyl acrylate (VBC-co-St-co-HEA) copolymer that can be applied to redox the flow battery process. The anion exchange membrane was prepared by the amination and crosslinking of VBC-co-St-co-HEA copolymer. The chemical structure and thermal properties of VBC-co-St-co-HEA copolymer and aminated VBC-co-St-co-HEA(AVSH) membrane were characterized by FTIR, $^1H$ NMR, TGA, and GPC analysis. The membrane properties such as ion exchange capacity(IEC), electrical resistance, ion conductivity and efficiency of all-vanadium redox flow battery were measured. The IEC value, electrical resistance, and ion conductivity were 1.17 meq/g, $1.9{\Omega}{\cdot}cm^2$, 0.009 S/cm, respectively. The charge-discharge efficiency, voltage efficiency and energy efficiency from all-vanadium redox flow battery test were 99.5, 72.6 and 72.1%, respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.183-183
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• 2011

리튬 이온 배터리의 cathode 및 electrolyte 재료로 사용되는 LiCoO2을 sputtering이나 pulsed laser deposition을 이용하여 박막으로 증착하기 위해서는 target이 필요하다. Target은 원료 분말을 가압 성형한 후 고온에서 소결하여 제조된다. LiCoO2 target 제조과정에서 고밀도를 얻기 힘들고 Li 성분의 증발이 일어난다. 또한 Li2O 분말은 흡습성이 매우 크다. 본 연구에서는 시간과 온도를 조절하여 최적화된 소결 과정을 통해 target의 밀도가 이론밀도와 근사한 값을 갖도록 하고, LiCoO2 또는 Co3O4 분말에 각각 흡습성이 낮은 Li2CO3 분말을 첨가하여 Li 성분을 조절하였다. Li과 Co의 조성비가 1:1-2:1인 고밀도의 LiCoO2 target을 제조하여 박막 증착 후 Li과 Co의 조성비가 1:1이 되도록 하였다.

• Microbiology and Biotechnology Letters
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• v.48 no.4
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• pp.547-555
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• 2020

Microalgae are a promising resource in energy and food production as they are cost-effective for biomass production and accumulate valuable biological resources. In this study, CO2 assimilation, biomass, and lipid production of 4 microalgal species (Chlorella vulgaris, Mychonastes homosphaera, Coelastrella sp., and Coelastrella vacuolata) were characterized at different CO2 concentrations ranging from 1% to 9%. Microscopic observation indicated that C. vulgaris was the smallest, followed by M. homosphaera, C. vacuolata, and Coelastrella sp. in order of size. C. vulgaris grew and consumed CO2 more rapidly than any other species. C. vulgaris exhibited a linear increase in CO2 assimilation (up to 9.62 mmol·day-1·l-1) as initial biomass increased, while the others did not (up to about 3 mmol·day-1·l-1). C. vulgaris, Coelastrella sp., and C. vacuolata showed a linear increase in the specific CO2 assimilation rate with CO2 concentration, whereas M. homosphaera did not. Moreover, C. vulgaris had a greater CO2 assimilation rate compared to those of the other species (14.6 vs. ≤ 11.9 mmol·day-1·l-1). Nile-red lipid analysis showed that lipid production per volume increased linearly with CO2 concentration in all species. However, C. vulgaris increased lipid production to 18 mg·l-1, compared to the 12 mg·l-1 produced by the other species. Thus, C. vulgaris exhibited higher biomass and lipid production rates with greater CO2 assimilation capacity than any other species.

• Korean Journal of Exercise Nutrition
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• v.16 no.1
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• pp.1-9
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• 2012

Long chain fatty acids (LCFAs) are transported into cells via plasma transporters, are activated to fatty acyl-CoA by fatty acyl-CoA synthase (ACS), and enter mitochondria via the carnitine system (CPT1/CACT/CPT2). The mitochondrial carnitine system plays an obligatory role in β-oxidation of LCFAs by catalyzing their transport into the mitochondrial matrix. Fatty acyl-CoAs are oxidized via the β-oxidation pathway, which results in the production of acetyl-CoA. The acetyl-CoA can be imported into the tricarboxylic acid (TCA) cycle for oxidation in the mitochondrial matrix or can be used for malonyl-CoA synthesis by acetyl-CoA carboxylase 2 (ACC2) in the cytoplasm. In skeletal muscle, ACC2 catalyzes the carboxylation of acetyl-CoA to form malonyl-CoA, which is a potent endogenous inhibitor of carnitine palmitoyltransferase 1 (CPT1). Thus, ACC2 indirectly inhibits the influx of fatty acids into the mitochondria. Fatty acid metabolism can also be regulated by malonyl-CoA-mediated inhibition of CPT1.