• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.847-852
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• 2008

In order to determine the effects of puffing red ginseng (PRG) powder on the antioxidant enzyme activities of hepatotoxicity in benzo($\alpha$) pyrene[B($\alpha$)P]-treated mice, the mice were divided into 5 groups. The dried red ginseng were prepared by puffing conditions of moisture content 10% and puffing pressure $5\;kgf/cm^2$, and then powdered. PRG powder was injected i.p. 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 between lipid peroxidation and PRG powder on oxidative stress. The increased activities of superoxide dismutase, catalase, and glutathione peroxidase observed following B($\alpha$)P-treatment were reduced by the treatment of PRG powder. Whereas the glutathione content and glutathione S-transferase activity depleted by B $\alpha$)P were significantly increased, the B($\alpha$)P-associated elevation of cytochrome P-450 activities and lipid peroxide content were reduced as the result of PRG powder treatment. Especially, PRG powder had higher antioxidant activities than RG powder. These results suggest that puffing red ginseng powder can protect against B($\alpha$)P intoxicification through its antioxidant properties.

• Progress in Superconductivity and Cryogenics
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• v.21 no.1
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• pp.18-24
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• 2019

This study was carried out to investigate the effect of milling of boron (B), which is one of raw materials of $MgB_2$, on the critical current density ($J_c$) of $MgB_2$. B powder used in this study is semi-amorphous B (Pavezyum, Turkey, 97% purity, 1 micron). The size of B powder was reduced by planetary milling using $ZrO_2$ balls (a diameter of 2 mm). The B powder and balls with a ratio of 1:20 were charged in a ceramic jar and then the jar was filled with toluene. The milling time was varied from 0 to 8 h. The milled B powders were mixed with Mg powder in the composition of (Mg+2B), and the powder mixtures were uniaxially pressed at 3 tons. The powder compacts were heat-treated at $700^{\circ}C$ for 1 h in flowing argon gas. Powder X-ray diffraction and FWHM (Full width at half maximum) were used to analyze the phase formation and crystallinity of $MgB_2$. The superconducting transition temperature ($T_c$) and $J_c$ of $MgB_2$ were measured using a magnetic property measurement system (MPMS). It was found that $B_2O_3$ was formed by B milling and the subsequent drying process, and the volume fraction of $B_2O_3$ increased as milling time increased. The $T_c$ of $MgB_2$ decreased with increasing milling time, which was explained in terms of the decreased volume fraction of $MgB_2$, the line broadening of $MgB_2$ peaks and the formation of $B_2O_3$. The $J_c$ at 5 K increased with increasing milling time. The $J_c$ increase is more remarkable at the magnetic field higher than 3 T. The $J_c$ at 5 K and 4 T was the highest as $4.37{\times}10^4A/cm^2$ when milling time was 2 h. The $J_c$ at 20 K also increased with increasing milling time. However, The $J_c$ of the samples with the prolonged milling for 6 and 8 h were lower than that of the non-milled sample.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.6
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• pp.830-837
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• 2011

This study was carried out to investigate the quality characteristics of yellow layer cake mulberry powder. After making yellow layer cake with mulberry powder, water activity, crumb texture, crumb color, and sensory tests were investigated. After 1 day of storage, Aw of control with weak flour did not show any significant difference, whereas those with 1, 3. 5% mulberry powder showed a significant decrease in Aw. During storage, the Aw values of yellow layer cakes containing mulberry powder were consistent. Hardness, springiness, cohesiveness, and gumminess of the yellow layer cakes containing mulberry powder all decreased compared to those of control. Hardness, springiness, cohesiveness, and gumminess all increased with storage time. Further a higher percentage of mulberry powder was associated with a lower L value, but higher a value. b values were lower in the 1% and 3% mulberry powders, but 5% showed a slightly higher b value. An increase in storage time was associated with decreased L and b values and increased a value. The micrographs of yellow layer cakes with mulberry powder showed a slightly coarser porosity than that of controls. The results of the sensory test showed that the over-all acceptability of 1% mulberry powder cake was the best.

• Journal of Powder Materials
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• v.23 no.3
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• pp.202-206
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• 2016

A Ni-Ti-B alloy powder prepared by mechanical alloying (MA) of individual Ni, Ti, and B components is examined with the aim of elucidating the phase transitions and crystallization during heat treatment. Ti and B atoms penetrating into the Ni lattice result in a Ni (Ti, B) solid solution and an amorphous phase. Differential thermal analysis (DTA) reveals peaks related to the decomposition of the metastable Ni (Ti, B) solid solution and the separation of equilibrium $Ni_3Ti$, $TiB_2$, and ${\tau}-Ni_20Ti_3B_6$ phases. The exothermal effects in the DTA curves move to lower temperatures with increasing milling time. The formation of a $TiB_2$ phase by annealing indicates that the mechanochemical reaction of the Ni-Ti-B alloy does not comply with the alloy composition in the ternary phase diagram, and Ti-B bonds are found to be more preferable than Ni-B bonds.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.5
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• pp.247-253
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• 2012

In this study, two pretreatment methods were used to improve the sinterability of zirconium diboride ($ZrB_2$). As a mechanical treatment, as-received $ZrB_2$ powder was crushed using SPEX mill from an average size of $2.61{\mu}m$ to $0.35{\mu}m$. As a chemical treatment, oxygen contents of $ZrB_2$ powder were decreased from 4.20 wt% to 2.22 wt% using a dilute hydrofluoric solution. The relative density of sintered $ZrB_2$ increased with decreasing particle size and oxygen contents. But it is considered that particle size is more effective than oxygen contents for $ZrB_2$ densification. Through the two pretreatment processes, we produced sintered $ZrB_2$ ceramic with a full density without sintering additives. The sinterability of $ZrB_2$ was improved by using mechanical and chemical pretreatment methods.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1080-1081
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• 2006

In this investigation, $B_4C$ based ceramic composites were fabricated by in-situ reaction hot pressing using $B_4C$, TiC SiC powder as starting materials. The reaction synthesized composites by hot pressing at $1950^{\circ}C$ was found to posses very high relative density. The reaction synthesized $B_4C$ composites comprise $B_4C$, $TiB_2$, SiC and graphite by the reaction between TiC and $B_4C$. The newly formed $TiB_2$ and graphite was embedded both inside grain and at grain boundary $B_4C$. The mechanical properties of reaction synthesized $B_4C-TiB_2-SiC$-graphite composites were more enhanced compared to those of monolithic $B_4C$.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2005.11a
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• pp.34-34
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• 2005

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2005.11a
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• pp.43-43
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• 2005

• Journal of the Korean Society of Food Culture
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• v.12 no.5
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• pp.469-475
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• 1997

The modification of rice powder was attempted by treatment of acetic acid and epichlorohydrin to improve the functional properties of baby food. The initial gelatinization temperature of rice powder determined by amylograph was decreased from $79.5^{\circ}C$ to $63^{\circ}C$ by modification. The apparent and maxium viscosity of rice paste at $95^{\circ}C$ before and after modification were increased from 92B.U. to 236B.U. and from 100B.U. to 202B.U., respectively. The light transmittance of modified rice paste was increased from the temperature of $60^{\circ}C$ and by increasing the degree of substitution at the fixed temperature, while decrease more or less by the treatment of epichlorohydrin. The degree of retrogradation of the paste was decreased from 28.7 to 18.0 upon modification. The rate of syneresis of modified rice powder was decreased with increasing the drgree of substitution and ,the extend of epichlorohydrin treatment. Syneresis was not observed when acetylated rice powder whose DS value is 0.048 was treated with 0.25% of epichlorohydrin for the formation of cross-linkage. The addition of modified rice powder in preparation of semi-solid type infant food could improve the quality without lowering overall digestibility.

• Proceedings of the Korean Magnestics Society Conference
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• 2013.12a
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• pp.110-110
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• 2013