• Journal of Welding and Joining
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• 제15권1호
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• pp.116-124
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• 1997

A scope of this study is to establish the optimum plasma spray conditions for fine ($5\mu\textrm{m}$) $Al_2O_3$ powder. However, the flowability of the $Al_2O_3$ powder is not so good because of irregular particle shape and fine particle size. Therefore, powder feeding system was modified by 1) change of powder feeding line material from polymer to copper 2) shorten the powder feeding tube length 3) heating the powder feeding system to $80^{\circ}C$4) vibrating the powder feeding line continuously, in order to feed the fine powder homogeneously. The homogeneous powder feeding conditions were obtained with the modified powder feeding system by controlling the powder carrier gas flow and the powder flow rate indicator. The best plasma spraying conditions for the fine $Al_2O_3$ powder were found out as 40kw gun power, 80 g/min. powder feed rate and 50 mm working distance after characterizing the microstructure, hardness and wear loss of the $Al_2O_3$ coating layer.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.769-770
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• 2006

The MIM industry is currently focusing on parts that are used in automobiles and medical instruments. Many of the parts in these categories are very small and often not easy to machine because of its complex geometry. Therefore MIM is well suited for the production of these parts. We tested the sinterability of SUS316L ultra fine powders (3,4, 6, 8micron) produced by ATMIX high-pressure water-atomization, and it showed excellent results. A density of 97% theoretical was obtained by sintering at 1373K when using the ultra fine powder (3micron). Specifically, the finer the powder size, higher was the sintered density. The surface roughness and accuracy are also greatly improved with ATMIX ultra fine powder.

• 동의신경정신과학회지
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• 제19권2호
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• pp.95-110
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• 2008

Objective : This experiment was designed to investigate the effects of the PMCMT hot water extract & ultra-fine powder on Alzheimer's Disease Model Induced by ${\beta}A$. Method : The effects of the PMCMT hot water extract on expression of proinf1ammatory cytokine mRNA in BV2 microglial cell cell line treated by lipopolysacchaide(LPS). The effects of the PMCMT hot water extract & ultra-fine powder on (1) the behavior (2) AChE in serum (3) the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with ${\beta}A$ were investigated. Result : 1. The PMCMT hot water extract suppressed the expression of proinflammatory cytokine mRNA in BV2 microglial cell line treated with LPS. 2. The PMCMT hot water extract & ultra-fine powder a significant inhibitory effect on the memory deficit was shown for the mice with Alzheimer's disease induced by ${\beta}A$ in the Morris water maze experiment, which measured stop-through latency and distance movement-through latency 3. The PMCMT hot water extract & ultra-fine powder suppressed the over-expression of AChE activity in the serum of the mice with Alzheimer's disease induced by ${\beta}A$. 5. The PMCMT ultra-fine powder reduced infarction area of hippocampus significantly, and the PMCMT hot water extract & ultra-fine powder controlled the injury of brain tissue in the mice with Alzheimer's disease induced by ${\beta}A$. Conclusions : These results suggest that the PMCMT hot water extract & ultra-fine powder may be effective for the prevention and treatment of Alzheimer's disease. Investigation into the clinical use of the PMCMT hot water extract & ultra-fine powder for Alzheimer's disease is suggested for future research.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.712-713
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• 2006

We successfully developed Al-Si-Transition Metal (TM) -Rare Earth (RE) Powder Metallurgy (P/M) alloy with fine microstructure, which has high strength at high temperature. This material was compacted rapidly solidified powder and directly consolidated by hot extruding or forging. Before consolidating, rapid heating was performed on powder compaction in order to keep the fine microstructure in powder state. We have also investigated the processing conditions of this new alloy by computing simulations and experiments.

• 동의생리병리학회지
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• 제21권4호
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• pp.921-933
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• 2007

This experiment was designed to investigate the effects of the KBCMT hot water extract & ultra-fine powder on Alzheimer's Disease Model Induced by ${\beta}A$. The effects of the KBCMT hot water extract on expression of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, NOS-II, COX-2 mRNA and production of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, NO in BV2 microglial cell line treated by lipopolysacchaide(LPS). The effects of the KBCMT hot water extract & ultra-fine powder on (1) the behavior (2) expression of $IL-1{\beta}$, $TNF-{\alpha}$, MDA, CD68 and CD11b; (3) AChE in serum (4) the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with ${\beta}A$ were investigated. The KBCMT hot water extract suppressed the expression of $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ mRNA in BV2 microglia cell line treated with LPS. The KBCMT hot water extract suppressed the production of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, NO in BV2 microglial cell line treated with LPS. The KBCMT hot water extract & ultra-fine powder a significant inhibitory effect on the memory deficit was shown for the mice with Alzheimer's disease induced by ${\beta}A$ in the Morris water maze experiment, which measured stop-through latency and distance movemet-through latency The KBCMT ultra-fine powder suppressed the expression of TNF-a protein significantly in the microglial cell of mice with Alzheimer's disease induced by ${\beta}A$. The KBCMT hot water extract & ultra-fine powder reduced the MDA and suppressed the over-expression of CD68, CD11b in the mice with Alzheimer's disease induced by ${\beta}A$. The KBCMT hot water extract & ultra-fine powder decreased AChE significantly in the serum of the mice with Alzheimer's disease induced by ${\beta}A$. The KBCMT hot water extract & ultra-fine powder reduced infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by ${\beta}A$. The KBCMT hot water extract & ultra-fine powder reduced the tau protein, GFAP, and presenilin1, 2 of hippocampus in the mice with Alzheimer's disease induced by ${\beta}A$. These results suggest that the KBCMT hot water extract & ultra-fine powder may be effective for the prevention and treatment of Alzheimer's disease. Investigation into the clinical use of the KBCMT hot water extract & ultra-fine powder for Alzheimer's disease is suggested for future research.

• 동의생리병리학회지
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• 제21권3호
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• pp.688-699
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• 2007

This experiment was designed to investigate the effect of the SST hot water extract & ultra-fine Powder on Alzheimer's Disease Model Induced by ${\beta}$A. The effects of the SST hot water extract on expression of IL-1${\beta}$, IL-6, TNF-${\alpha}$, NOS-II, COX-2 mRNA and production of IL-l${\beta}$, IL-6, TNF-${\alpha}$, NO in BV2 microglial cell line treated by lipopolysacchaide(LPS). The effects of the SST hot water extract & ultra-fine powder on (1) the behavior (2) expression of IL-1${\beta}$, TNF-${\alpha}$, MDA, (3) Glucose, AChE in serum (4) the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with ${\beta}$A were investigated. The SST hot water extract suppressed the expression of IL-1${\beta}$, IL-6 and TNF-a mRNA ${\alpha}$in BV2 microglia cell line treated with LPS. The SST hot water extract suppressed the production of IL-1${\beta}$, IL-6, TNF-${\alpha}$, NO in BV2 microglial cell line treated with LPS. The SST hot water extract & ultra-fine powder a significant inhibitory effect on the memory deficit was shown for the mice with Alzheimer's disease induced by ${\beta}$A in the Morris water maze experiment, which measured stop-through latency. The SST ultra-fine powder suppressed the expression of TNF-a protein significantly in the microglial cell of mice with Alzheimer's disease induced by ${\beta}$A. The SST hot water extract & ultra-fine powder reduced the MDA and suppressed the over-expression of CD68, CD11b in the mice with Alzheimer's disease induced by ${\beta}$A. The SST hot water extract & ultra-fine powder decreased AChE significantly in the serum of the mice with Alzheimer's disease induced by ${\beta}$A. The SST hot water extract & ultra-fine powder reduced infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by ${\beta}$A. The SST hot water extract & ultra-fine powder reduced the tau protein, GFAP, and presenilin1, 2 of hippocampus in the mice with Alzheimer's disease induced by ${\beta}$A. These results suggest that the SST hot water extract & ultra-fine powder may be effective for the prevention and treatment of A1zheimer's disease. Investigation into the clinical use of the SST hot water extract & ultra-fine powder for Alzheimer's disease is suggested for future research.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.889-890
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• 2006

In recent years, PCB drills with smaller diameters less than 0.1 mm are used and thus there are growing needs for ultra-fine grained cemented carbides. However, ultra-fine WC powder usually causes extraordinary grain growth during sintering which weakens mechanical strength of ultra-fine grained cemented carbides. So we examined several kinds of WC powders to make new ultra-fine grained cemented carbides having superior performance. We found that direct carburized WC powder is very good as a WC raw material. The PCB drills made of the developed ultra-fine grained cemented carbides have higher hardness, toughness and stiffness than conventional ones.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.444-445
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• 2006

Flying trajectories of fine particles within a size range of $10{\sim}60{\mu}m$ were studied during centrifugal atomizing processes. A FORTRAN program was written by using increment method. Calculation results revealed that the drag force might reach very high value of 522-7800 g for fine powder of $10{\sim}60{\mu}m$. Flying distance in horizontal direction could be shortened if the particles fly obliquely due to the huge drug force. On the other hand, very fine powder could be projected to far distances when the atmosphere flow velocity is much stronger. Fortunately such particles could be contracted within a cylinder closed to the atomizer when the atmosphere flow was weaken or retained in a limited diameter.

• 동의신경정신과학회지
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• 제19권3호
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• pp.85-100
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• 2008

Objective: This experiment was designed to investigate the effect of the KSKH hot water extract & ultra-fine powder on microglia and memory deficit model. Method: The effects of the KSKH hot water extract on expression of IL-1$\beta$, IL-6, TNF-$\alpha$ mRNA and production of IL-1$\beta$, IL-6, TNF-$\alpha$ in BV2 microglial cell line treated by lipopolysacchaide(LPS) were investigated. The effects of the KSKH hot water extract & ultra-fine-fine powder on the behavior of the memory deficit mice induced by scopolamine and AChE in serum of the memory deficit mice induced by scopolamine were investigated. Results: 1. The KSKH hot water extract suppressed the expression of IL-1$\beta$, IL-6, TNF-$\alpha$ mRNA in BV2 microglial cell line treated by LPS. 2. The KSKH hot water extract suppressed the production of IL-1$\beta$, IL-6, TNF-$\alpha$ in 100$\mu g/m\ell$ concentration of BV2 microglial cell line culture supernatant. 3. The KSKH hot water extract & ultra-fine powder decreased AChE activation significantly in the serum of the memory deficit mice induced by scopolamine. 4. The KSKH hot water extract & ultra-fine powder showed significant effect on memory impairment in the stop-through latency type of Morris water maze test. Conclusions: This experiment shows that the KSKH hot water extract & ultra-fine powder might be effective for the prevention and treatment of amnesia and Alzheimer's disease. Investigation into the clinical use of the KSKH hot water extract & ultra-fine powder for amnesia and Alzheimer's disease is suggested for future research.

• 한국잠사곤충학회지
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• 제43권1호
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• pp.41-48
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• 2001

The purification, dissolution and powdering of stained waste silk obtained from weaving and dyeing process were studied for the surface modification of textile fabric and plastic materials. The whiteness of stained waste silk could be improved through degumming and bleaching with sodium hydrosulfite. The water-soluble fibroin solution can be obtained by dissoving the degummed waste silk in a boiling solution of 50% calcium chloride for 60 minutes. The salts and heavy metals contained in fibroin solution were removed by electric dialysis, wool fiber filtration and gel filtration chromatography. The fibroin powder was prepared by using a fine grinder after the alkali treatment for weakening the silk fiber. The fine fibroin powder of particle size around 30 ㎛ was obtained with a ultra fine-mill, while it was finer below 10 ㎛ with a ball-mill. The dissolved or powdered silk was applied to the surface of fabric with addition of the binder (a urethane resin). The moisture content of polyester and nylon fabrics treated with the silk solution was improved due to hygroscopic property of silk. The fine fibroin powder mixed with the binder ws coated on the surface of synthetic film by use of the air pressed sprayer. It was revealed that the hygroscopicity as well as the softness of fibroin powder coated film was much improved. Therefore, it is thought that the fine silk fibroin powder is applicable as an coating agent for the surface modification of plastic and synthetic leather.