• 한국분말재료학회지
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• 제19권4호
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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.

• 한국축산식품학회지
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• 제24권1호
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• pp.15-22
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• 2004

규격돈의 비육돈육(B 등급육)에 0.3%의 쑥 분말을 첨가한 수육(B$_{+}$ 수육)과 첨가하지 않은 수육(B$_{0}$ 수육), 그리고 종빈돈에서 생산된 육(E 등급육)에 쑥 분말을 첨가한 수육(E$_{+}$ 수육)과 첨가하지 않은 수육(B$_{0}$ 수육)을 제조하고, 도체등급과 쑥 분말이 이화학적, 관능적 특성에 미치는 영향을 검토하였다. 수육의 pH, 휘발성 염기질소 함량, 일반세균 수, 열량, 필수아미노산, 유리아미노산, 불포화지방산 조성, 황색도, 종합적 기호도는 원료육의 등급과 쑥 분말 첨가 유무에 관계없이 유의적 차이를 나타내지 않았다. B$_{0}$수육의 보수력, 탄성 및 명도는 E$_{0}$ 수육보다 높았다(p＜0.05). B$_{0}$ 수육의 적색도는 E$_{0}$수육보다 낮게 나타났다(p＜0.05). B$_{0}$ 수육의 맛과 연도는 E$_{0}$ 수육보다 현저히 우수하였다(p<0.05). 쑥 분말 첨가에 의하여 수육의 보수력, TBARS 값 및 아질산이온 잔류량이 낮아졌다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2002년도 추계학술강연 및 발표대회
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• pp.33-33
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• 2002

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2002년도 추계학술강연 및 발표대회
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• pp.67-68
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• 2002

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 1999년도 춘계학술대회 및 발표대회 강연 및 발표논문 초록집
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• pp.8-8
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• 1999

• 한국분말재료학회지
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• 제15권3호
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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.

• 한국분말재료학회지
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• 제18권6호
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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.

• 한국분말재료학회지
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• 제10권6호
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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.

• 한국식품영양과학회지
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• 제33권1호
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• pp.201-206
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• 2004

쑥 분말의 첨가와 원료육 등급이 돼지고기 햄의 저장성에 미치는 영향을 검토하기 위하여, 규격돈(B등급) 및 경산모돈(E등급)에 쑥 분말을 첨가한 것과 첨가하지 않은 네 종류의 돼지고기 햄을 제조하였다. $L^{*}$ 값은 $B_{o}$ 및 $B_{+}$ 햄은 저장 후기가 높았으며, $E_{o}$ 햄은 저장 2주째 가장 높았고, $E_{+}$ 햄은 저장 중 변화가 없었다. 그러나 B등급육 햄의 $L^{*}$ 값이 E등급육 햄보다 높았으며, $a^{*}$ 값은 E등급육 햄이 높았다. 햄의 pH는 저장 중 감소하다가 저장 8주까지 증가하였다. 아질산 잔류량은 저장 2주까지 급격히 감소하였으며, 쑥 분말의 첨가는 아질산 잔류량의 감소에 영향을 미쳤다. VBN 함량은 저장초기 6.90∼7.90 mg%이던 것이 저장 중 증가하여 8주 째에는 14.07∼14.83 mg%를 나타내었다. TBARS는 저장 중 증가하였으며, 쑥 분말을 첨가한 것이 첨가하지 않은 것보다 저장 4주와 6주 째에 더 낮았다. 총균수는 모든 햄이 저장 중에 증가하였으며, 쑥 분말의 첨가는 총균수에 영향을 미치지 않았다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2004년도 춘계학술강연 및 발표대회 강연 및 발표논문 초록집
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• pp.47-47
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• 2004