• Proceedings of the KWS Conference
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• 2000.10a
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• pp.256-259
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• 2000

High viscosity mixing powder is a very useful material for laser cladding. This material has a high viscosity so that it can be sticked to substrate. Therefore, Laser cladding can be performed on a curved or slope surface. Laser cladding can be easily performed with the material instead of wire that is difficult to be manufactured in some case. In this experiment, it was used a high viscosity mixing powder which consists of a high temperature flux and a bronze powder. And AC2B alloy material was used as a substrate. Flux prevents the clad layer from being oxidized and increases bonding property between substrate and cladding material. It makes possible to laser cladding at low level energy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.9
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• pp.727-732
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• 1998

Ag-deposited graphite powder was prepared by a chemical reduction method of metal particles onto graphite powder. X-ray diffraction observation of Ag-deposited graphite powder revealed that silver existed in a metallic state, but not in an oxidized one. From SEM measurement, ultrafine silver particles were highly dispersed on the surface of graphite particles. Cylindrical lithium ion secondary battery was manufactured using Ag-deposited graphite anodes and $LiCoO_2$ cathodes. The cycleability of lithium ion secondary battery using Ag-deposited graphite anodes was superior to that of original graphite powder. The improved cycleability may be due to both the reduction of electric resistance between electrodes and the highly durable Ag-graphite anode.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.43-46
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• 2004

Multi-walled carbon nanotubes (MWNTs) produced by chemical vapor deposition were treated with acidic solution for purification and oxidization of CNTs. The surface modification of the oxidized CNTs was achieved by amine treatment and oxygen plasma treatment. The functionalized CNTs were embedded in the epoxy resin by sonication method and the resulting composite was investigated by FESEM. Rheological and mechanical properties of nanocomposites were measured by AR2000 and Instron. The rheological properties and dispersion of modified CNTs/epoxy composites were improved as CNTs were modified, because the modification of CNTs led to a improvement interaction between the CNTs and the epoxy resin. In addition to this, mechanical properties are also improved because of the effective stress transfer between the CNTs and the polymer.

• Journal of Industrial Technology
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• v.21 no.A
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• pp.17-26
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• 2001

The fatigue strength of SM55C has significantly decreased by 83% compared with atmosphere where distilled exists due to strong erosive action of acid fog. The reason is inferred in a way that strong acid erosive material such as acid fog act and give rise to multi-site crack on the surface. Several fatigue clacks occurred under the acid fog repeat the process of division and unification on the surface and form a long non-propagating crack throughout the circumference of experimented steel. However, in the depth, many parts do not show much trace of unification, and the depth is not as big as the one of normal crack shape. 10% of $CaCl_2$ causes strong erosive reaction to material. Then eventually make the life of fatigue shooter. On the other hand, 20% of $CaCl_2$ beings about oxidized material organic crack closing due to weak erosive reaction.

• Journal of Korea Foundry Society
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• v.25 no.6
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• pp.226-232
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• 2005

Contact material is widely used in the field of electrical parts. Ag-CdO material has a good wear resistance and stable contact resistance. In order to establish optimizing heat treatment condition, rolling temperature and oxidation process, we studied the microstructure of Ag-CdO material with various conditions. The experimental procedure were melting using high frequency induction, heat treatment, rolling and internal oxidation. And we experimented on difference process, Post-oxidaion. In this study, we obtained the optimizing heat treatment condition was $700^{\circ}C$ for 15 min. and the optimizing rolling temperature was $730^{\circ}C$. In investigation of the microstructure of oxidized material, coarse oxide and depleted oxidation layer existed. The hardness was average Hv 70. When we used Post-oxidation, oxides were finer than prior process and depleted oxidation layer did not exist. The hardness of Post-oxidation material was average Hv 80. And the optimizing rolling temperature was $800^{\circ}C$.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.04a
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• pp.153-155
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• 2008

M-aramid(in DMAc)를 전기 방사하여, chlorine을 부착시켜 항균성을 가지게 하였고, 부착된 chlorine의 농도는 titration을 통해 확인하였다. 15cm를 유지하여 방사했을 경우 10cm일 때에 비해 비드의 양이 적고, 비교적 균일한 형태로 방사되었다. 방사거리를 15cm로 유지시켜 방사한 m-aramid의 oxidized chlorine의 농도를 측정한 결과, 매우 우수한 수치를 보였고, 전압이 증가할수록 조금씩 감소하였다.

• Journal of the Korean Graphic Arts Communication Society
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• v.15 no.2
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• pp.131-143
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• 1997

Surface sizing is one of the important process to the paper making. Surface sizing had an effect on penetration of oils, physical propertiesm water resistance for the paper. This study was carried out for the purpose of improving printability with surface sizing of domestic newspaper. The samples were prepared by means of TAPPI method(TAPPI 205 om~88), and were wested by IGT printability tester. The results of this study showed that the set-off was reduced on the surface sized with oxidized starch.

• Korean Journal of Plant Resources
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• v.26 no.2
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• pp.227-233
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• 2013

This study was carried out to effects of Allium victorials extract on lowering lipid, anti-oxidation and concentration of inflammatory mediators in rats fed high oxidized fat. Concentration of free fatty acid(FFA), triglyceride(TG), total cholesterol and LDL-cholesterol in plasma decreased in the Allium victorials extract groups and plasma HDL-cholesterol concentration revealed a tendency to increase in Allium victorials extract groups. Concentration of total cholesterol and TG in liver showed a tendency to decrease in Allium victorials extract groups. Concentration of thiobarbituric acid(TBARS) in plasma and liver showed a lower values in Allium victorials extract groups than that of control group. Activities of glutathione peroxidase(GSH-Px), superoxide dismutase(SOD) and catalase(CAT) in liver showed a tendency to increase in Allium victorials extract groups. Concentration of nitrogen oxide(NO), ceruloplasmin and ${\alpha}1$-acid glycoprotein in plasma showed a lower values in Allium victorials extract groups than that of control group. These results indicate that the Allium victorials extract have an functional material for lowering lipid, anti-oxidation and anti-inflammatory effect.

• Journal of the Korean Ceramic Society
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• v.52 no.4
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• pp.243-247
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• 2015

Si(Al)ON precursor was synthesized by formation of new Si-N bond using organoaluminum imine and liquid type poly(phenyl carbosilane). It was decomposed between $200-600^{\circ}C$, and the ceramic yield was 51% after pyrolysis. 150 - 200 nm in thickness of coating film was obtained by spin coating method. The precursor was easily oxidized during process because it was unstable in air. However the oxygen content was limited to 0.5 - 0.7 to silicon in heat treatment step. Even though the content of nitrogen was decreased by pyrolysis, Al-N and Si-N bonds were formed in ammonia atmosphere, and Si(Al)ON film was formed with 0.2 in content to silicon.

• 한국연소학회:학술대회논문집
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• 2004.06a
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• pp.227-234
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• 2004

For gaseous fuel combustion with inherent $CO_2$ capture and low NOx emission, chemical-looping combustion(CLC) may yield great advantages of savings of energy to $CO_2$ separation and suppressing the effect on environment. In chemical-looping combustor, fuel is oxidized by metal oxide medium (oxygen carrier particle) in a reduction reactor. Reduced particles are transported to oxidation reactor and oxidized by air and recycled to reduction reactor. The fuel and the air are never mixed, and the gases from reduction reactor, $CO_2$ and $H_2O$, leave the system as separate stream. The $H_2O$ can be easily separated by condensation and pure $CO_2$ is obtained without any loss of energy for separation. The purpose of this study is to demonstrate inherent $CO_2$ separation and no NOx emission and to confirm high $CO_2$ selectivity, no side reaction (i.e., carbon deposition, hydrogen generation) by continuous reduction and oxidation experiment in a 50kWtb chemical-looping combustor. NiO/bentonite particle was used as a bed material and $CH_4$ and air were used as reacting gases for reduction and oxidation respectively.