• Journal of Powder Materials
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• v.19 no.4
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• pp.247-252
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• 2012

Effect of Cu and $DyF_3$ powder mixing with Cu-free (Nd, Dy)-Fe-B jet-milled powder on the magnetic properties of sintered magnets was investigated. The coercivity of a magnet prepared from the Cu-free (Nd, Dy)-Fe-B powder was about 10 kOe even though the alloy powder already contained some Dy (3.5 wt%). When small copper powder was blended, however, the coercivity of the magnet increased almost 100%, exhibiting about 20 kOe. On the contrary, the coercivity enhancement was moderate, about 4 kOe, when dysprosium content in the sintered magnet was simply increased to 4.9 wt% by the addition of small $DyF_3$3 powder.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.15-22
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• 2004

The effects of carcass grade and addition of mugwort powder on the quality of the boiled pork were investigated. Four kinds of boiled pork were denoted as B$\_$+/ or E$\_$+/ boiled porks which were made with 0.3% mugwort powder to carcass grade B or E, respectively, and B$\_$0/ or E$\_$0/ boiled porks which were made without mugwort powder. The effect of carcass grade and the added mugwort powder on the pH, volatile basic nitrogen(VBN), bacterial count, calorie, essential amino acids, free amino acids, unsaturated fatty acids, color difference and palatability of boiled porks were not significant. Water holding capacity(WHC), springiness and Hunter's L$\^$＊/ value of B$\_$0/ boiled pork were higher than those of E$\_$0/ boiled pork. Hunter's a$\^$＊/ value of B$\_$0/ boiled pork were lower than those of E$\_$0/ boiled pork. Sensory taste and tenderness value of B$\_$0/ boiled pork were higher than those of E$\_$0/ boiled pork(p>0.05). WHC, 2-thiobarbituric acid reactive substances(TBARS) value and residual nitrite of boiled pork with mugwort powder were lower than those of boiled pork without mugwort powder.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2002.11a
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• pp.33-33
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• 2002

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2002.11a
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• pp.67-68
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• 2002

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1999.04a
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• pp.8-8
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• 1999

• Journal of Powder Materials
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• v.15 no.3
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• pp.182-187
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• 2008

Carbon was known to be one of effective additives which can improve the flux pinning of $MgB_2$ at high magnetic fields. In this study, glycerin $(C_3H_8O_3)$ was selected as a chemical carbon source for the improvement of critical current density of $MgB_2$. In order to replace some of boron atoms by carbon atoms, the boron powder was heat-treated with liquid glycerin. The glycerin-treated boron powder was mixed with an appropriate amount of magnesium powder to $MgB_2$ composition and the powder pallets were heat treated at $650^{\circ}C\;and\;900^{\circ}C$ for 30 min in a flowing argon gas. It was found that the superconducting transition temperature $(T_c)$ of $Mg(B_{1-x}C_x)_2$ prepared using glycerin-treated boron powder was 36.6 K, which is slightly smaller than $T_c$(37.1 K) of undoped $MgB_2$. The critical current density $(J_c)$ of $Mg(B_{1-x}C_x)_2$ was higher than that of undoped $MgB_2$ and the $T_c$ improvement effect was more remarkable at higher magnetic fields. The $T_c$, decrease and $J_c$ increase associated with the glycerin treatment for boron powder was explained in terms of the carbon substitution to boron site.

• Journal of Powder Materials
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• v.18 no.6
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• pp.496-501
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• 2011

In this study, the effect of milling time on the microstructure and phase transformation behaviors of Ni-12 wt.%B powders was investigated using vibratory ball milling process. X-ray diffraction patterns showed that the phase transformation of mixed Ni-B elemental powder occurred after 50 hours of milling, with a formation of nickel boride phases. Through the study of microstructures in mechanical alloying process, it was considered that ball milling strongly accelerates solid-state diffusions of the Ni and B atoms during mechanical alloying process. The results of X-ray photoelectron spectroscopy showed that most of B atoms in the powder were linked to Ni with a formation of nickel boride phases after 200 hours of milling. It was finally concluded that mechanical alloying using ball milling process is feasible to synthesize fine and uniform nickel boride powders.

• Journal of Powder Materials
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• v.10 no.6
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• pp.436-442
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• 2003

The magnetic Nd-Fe-B powders were prepared by a thermochemical method, consisting of the processes of spray-drying, debinding, milling, H$_2$-reduction, Ca-reduction, and washing. The optimum process conditions were studied by microstructural and thermal analysis. The resultant Nd-Fe-B powder was spherical with the size of 1 ${\mu}{\textrm}{m}$. Effects of the process parameters of each step on the microstructure of the powders were investigated, and their magnetic properties were evaluated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.201-206
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• 2004

This study was carried out to investigate the effect of addition mugwort podwer and carcass grade on the shelf life of pork ham. Pork ham was prepared by four type such as grade B pork ham ( $B_{o}$ ), grade B pork ham containing mugwort powder ( $B_{+}$), grade E pork ham ( $E_{o}$ ) and grade E pork ham containing mugwort powder ( $E_{+}$). The surface color, pH, residual nitrite, VBN (volatile basic nitrogen), TBARS (2-thiobarbituric acid reactive substances) and total bacterial counts of the samples were determined during storage for 8 weeks at 4$^{\circ}C$. The $L^{*}$ value of $B_{o}$ and $B_{+}$ ham showed higher at the latter period of 8 weeks, that of $E_{o}$ ham was the highest on at the storage of 2nd week and that of $E_{+}$ ham was not different during 8 weeks storage. The $L^{*}$ value of B grade ham was higher than that of E grade ham and the $a^{*}$ value of E grade ham was higher than that of B grade ham. The pH of all ham decreased during storage, but increased from 8 weeks. The residual nitrite of all ham highly decreased until storage for 2 weeks, the addition of mugwort powder was affected in the reduction of residual nitrite of pork ham. The VBN contents were 6.90∼7.90 mg% in the early period of storage, was 14.07∼14.83 mg% on the storage of 8th week. The TBARS of pork ham were increased gradually during storage and pork ham containing mugwort powder showed lower value than pork ham non added mugwort powder during 4th and 6th weeks storage. The total bacterial counts of pork ham were increased gradually during storage and the addition of mugwort powder was not effective.ive.ctive.ive.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2004.04a
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• pp.47-47
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• 2004