• 한국초전도학회:학술대회논문집
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• v.10
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• pp.211-215
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• 2000

Bi-2212 HTS tube was fabricated by CFP(Centrifugal Forming Process). Slury was prepared in the mixing ratio of 8:2 between powder and binder and ball-milled for 24 hrs. Slurry was initially charged into the rotating mold with 300${\sim}$450 rpm and heated at the temperature ranges of 840${\sim}$860$^{\circ}$C for partial melting to finally obtain a uniformly textured tube shape. It was observed the plate-like grains with more than 20 ${\mu}$m were well oriented along the rotating axis and the measured T$_c$ was around 67K. In this paper we will discuss and analyze the tube characteristics depending on many different processing parameters such as, powder composition, binder mixing ratio between powder and binder, motor speed, heating temperature and etc.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.77-78
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• 2011

This study is analysis of effect of binder types and replacement ratio on the properties of blast furnace slag mortar using the recycled fine aggregates. The results of the study were was follows. Compressive strength was increased according to an increase in replacement ratio of fine particle cement and gypsum. Absorption was reduced according to an increase in replacement ratio of fine particle cement and recycled aggregate fine powder.

• Journal of Welding and Joining
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• v.20 no.2
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• pp.109-115
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• 2002

In the case of using high temperature by coating ceramic/metal, large stress was produced due to difference of thermal expansion coefficient between those. And then lead to delamination. In order to relaxation of the stress A1$_2$O$_3$/SS316 composite powders with $10wt.%Al_2O_3$ compositional gradient and $10wt.%Al_2O_3$ agglomerated powder were made by spray drying method. These powders were sintered to improve the strength and to be plasma sprayed in order to fabricate the FGC(functionally graded coating). The influence of gun power, working distance and Ar pressure on the microstructure of the coating layer was studied in order to optimize the plasma spray conditions. It was proven that the optimum conditions were 40kw gun power, 5cm working distance and $100ft^3/h$ Ar flow for both powders. FGC with 10 compositional steps was fabricated and the total thickness was 1.3mm. FGC was heat treated at $1100^{\circ}C$for 10hours to evaluate the heat resisting characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.91-99
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• 2016

Aster yomena is a perennial plant that belongs to the Asteraceae family. Seasoned wild vegetables are commonly used as functional ingredients because of their bioactive effects against oxidation, cancer, and inflammation. A recent report showed that ethanol extracts from Aster yomena effectively inhibited gene expression related to lipid accumulation within interstitial cells to prevent obesity, further raising awareness of its usefulness as a highly functional ingredient. Several studies have investigated Aster yomena, but none have investigated the effects of processing on its use. Therefore, this study investigated the quality characteristics and antioxidative activity of breads in which refined salt was replaced with Aster yomena powder at 0, 0.5, 1.0, 1.5, or 2.0%. Bread containing any amount of Aster yomena powder did not differ significantly from the control in terms of appearance, aroma, taste, texture, and overall preference. In addition, higher levels of added Aster yomena powder were associated with greater 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity indicating the potential for production of highly functional bread and noodle products using this material.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.217-221
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• 2007

In order to determine the effects of ginseng powder on the antioxidant enzyme activities of hepatotoxicity in $benzo({\alpha})pyrene[B({\alpha})P]-treated$ mice, the mice were divided into 5 groups. Ginseng powder was injected intraperitoneally once a day for 5 successive days, followed by the administration of $B({\alpha})P$ treatment on the fifth day. We also evaluated the relationship existing between lipid peroxidation and ginseng powder on oxidative stress. The increased activities of superoxide dismutase, catalase, and glutathione peroxidase observed following $B({\alpha})P-treatment$ were reduced as the result of ginseng powder treatment. Whereas, the glutathione content and glutathione S-transferase activity depleted by $B({\alpha})P$ were increased significantly, but the $B({\alpha})P-associated$ elevation of cytochrome P-450 activities and lipid peroxide content were reduced as the result of ginseng powder treatment. These results indicate that ginseng powder may exert a protective effect against $B({\alpha})P-induced$ hepatotoxicity in mice.

• Journal of Powder Materials
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• v.30 no.6
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• pp.484-492
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• 2023

In this study, Ni-Y₂O₃ powder was prepared by alloying recomposition oxidation sintering (AROS), solution combustion synthesis (SCS), and conventional mechanical alloying (MA). The microstructure and mechanical properties of the alloys were investigated by spark plasma sintering (SPS). Among the Ni-Y₂O₃ powders synthesized by the three methods, the AROS powder had approximately 5 nm of Y₂O₃ crystals uniformly distributed within the Ni particles, whereas the SCS powder contained a mixture of Ni and Y₂O₃ nanoparticles, and the MA powder formed small Y₂O₃ crystals on the surface of large Ni particles by milling the mixture of Ni and Y₂O₃. The average grain size of Y₂O₃ in the sintered alloys was approximately 15 nm, with the AROS sinter having the smallest, followed by the SCS sinter at 18 nm, and the MA sinter at 22 nm. The yield strength (YS) of the SCS- and MA-sintered alloys were 1511 and 1688 MPa, respectively, which are lower than the YS value of 1697 MPa for the AROS-sintered alloys. The AROS alloy exhibited improved strength compared to the alloys fabricated by SCS and conventional MA methods, primarily because of the increased strengthening from the finer Y₂O₃ particles and Ni grains.

• Journal of Powder Materials
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• v.17 no.3
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• pp.235-241
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• 2010

Mo nanopowder was synthesized by ball-milling and subsequent hydrogen-reduction of $MoO_3$ powder. To fabricate ultra fine grained molybdenum, two-step sintering and spark plasma sintering process were employed. The grain size of specimen by two-step sintering and spark plasma sintering was around $0.6\;{\mu}m$ and $0.4\;{\mu}m$, respectively. Mechanical properties of ultra fine grained Mo with relative density of above 90% were significantly improved at room and high temperatures comparing to commercial bulk Mo of 99% relative density. This result was mainly explained by the grain size refinement due to diffusion-controlled sintering.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1141-1146
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• 2012

Ce-doped $Y_3Al_5O_{12}$ (YAG:Ce) phosphor powder was prepared using a ${NO_3}^-$-malonic acid-$NH_4NO_3-NH_3{\cdot}H_2O$ system. The YAG:Ce precursor was ignited at $240^{\circ}C$ and the resulting powder contained YAG:Ce crystallites (42%) - active in the visible region at 460 nm - amorphous particles (53%) - inactive at visible wavelengths - and less than 3% oxide (3%) crystallite impurities. The impurities transformed to acitive YAG:Ce crystallites at above $800^{\circ}C$. At above $1000^{\circ}C$, the amorphous phase became YAG phase and isolated $Ce_2O$ crystallites emerged. The powder particles comprised < $4{\mu}m$ secondary aggregates of 20 nm primary particles. The thermal dusting of the secondary particles coincided with the aggregation of the secondary particles at above $900^{\circ}C$.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.1
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• pp.39-45
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• 2014

Various approaches have been tried to reduce the emission of carbon dioxide in paper industry. One of important approaches is to use PCC manufactured from emission gas as a filler. However, it was recognized that PCC is inferior to other fillers in the paper strength properties of view. Therefore, pretreatment of PCC with pulp powder was tried to mitigate the strength reduction of paper. Pretreatment of PCC with pulp powder improved the bulk(7.4~12.9%) and air permeability(24.8~42.98%), but there is no significant change in opacity. Tensile index, burst index and stiffness were decreased by the use of pretreated PCC with pulp powder. Anionic and cationic PAM were used as a additive for PCC pretreatment in order to improve strength properties. There was no significant change in bulk in all kinds of PAM used in this study. Most strength properties were improved by the pretreatment of PCC with the anionic and cationic PAM and pulp powder, although the opacity and stiffness were more or less decreased.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.804-812
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• 2017

This study was carried out to determine the physicochemical, microbiological, and quality characteristics of a new type of fermented sausage manufactured by incorporating Baechu-kimchi powder and gamma-aminobutyric acid (GABA)-producing lactic acid bacteria (LAB). The LAB count was at the maximum level by day nine of ripening in inoculated sausages, accompanied by a rapid decrease in the pH. The addition of kimchi powder decreased the lightness ($L^*$) and increased the redness ($a^*$) and, yellowness ($b^*$) values, while also significantly increasing the hardness and chewiness of the sausage (p<0.05). Moreover, although the thiobarbituric acid reactive substances values increased in all samples during the study period, this increase was lower in the kimchi-treated samples, indicating a reduction in lipid oxidation. Overall, our results show that the addition of Baechu-kimchi powder to sausages reduced the off-flavor properties and improved the taste profile of the fermented sausage in sensory evaluations. The GABA content of all fermented sausages increased from 17.42-25.14 mg/kg on the third day of fermentation to 60.95-61.47 mg/kg on the thirtieth day. These results demonstrate that Baechu-kimchi powder and GABA-producing LAB could be functional materials in fermented sausage to improve quality characteristics.