• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1994.10b
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• pp.24-24
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• 1994

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1999.10a
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• pp.10-10
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• 1999

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2002.04b
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• pp.56-56
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• 2002

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1997.04a
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• pp.18-19
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• 1997

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 1997.04a
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• pp.28-28
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• 1997

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2003.04a
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• pp.30-30
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• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2000.11a
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• pp.45-45
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• 2000

• Journal of the Korean Ceramic Society
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• v.38 no.11
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• pp.987-992
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• 2001

A refractory grade low-cost silicon nitride powder was chemically analyzed, purified, and gas pressure sintered with the sintering additives. As-received powder contained a significant amount of free-Si, 0.72 wt% of Fe, 0.5 wt% of al and 0.31 wt% of Ca. Oxygen and carbon contents of the powder were 3.3 wt% and 0.4 wt%, respectively, and it consisted of 96% of $\beta$-phase and 4% of $\alpha$-phase. After lowering the Fe content and nitriding treatment, the powder was sintered with 6 wt% yttria and 2 wt% alumina for 1 h between 1823 K and 2123 K in order to examine the sintering behavior. Fully dense samples were obtained by sintering at 2123k for 2h. For comparison, a commercially available high-grade powder was also sintered at the same time. The low-cost powder showed much slower densification rate than the high-grade powder. Fully dense sample prepared from the low-cost powder contained a number of coarse grains with a low aspect ratio, and its hardness, fracture toughness, flexural strength and thermal shock resistance were not as good as those of the sample prepared with the high-grade powder.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.406-407
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• 2005

사용후핵연료 차세대관리공정에서는 $UO_2$ 펠렛을 균질화된 $U_{3}O_8$의 분말 형태로 되어야만 금속 전환공정에서 반응효율을 높일 수 있다. 본 연구에서는 실증용 건식분말화 장치에서 분말의 비산을 방지하면서 산화 효율을 최대한 높일 수 있는 최적 조건을 찾는데 있다고 할 수 있다. 본 연구의 실험에서 $UO_2$ 펠렛(약 90 g)에 유량별 공정 변수를 주어 최적화된 산화 조건을 조사하였다. 그 결과, $500^{\circ}C$ 에서 유량은 이론 산화량의 2배(1640 cc/min)의 조건에서 최적의 산화 효율을 보여주었다. 따라서 본 연구에서 실증용 건식분말화 장치의 비산을 방지하면서 산화 효율을 최대한 높일 수 있는 최적 유량을 결정하였다.

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.29-32
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• 2007

This study was carried out to investigate the effect of emulsifiers on the characteristics of microcapsule containing squid liver oil. The emulsion stability of glycerine monostearate (HLB 4) separated after 1 hr. Sucrose fatty acid esters (monostearate: di-, tri-, and tetrastearate=6:4; HLB 11), sucrose fatty acid esters (monostearate: di-, tri-, and tetrastearate=7:3; HLB 16) and glycerine monostearate (HLB 4) plus sucrose fatty acid esters (monostearate: di-, tri-, and tetrastearate= 7:3; HLB 16) separated after 1 hr 30 min. The microencapsulation efficiency prepared by HLB 16 was 35.0%. The polyunsaturated fatty acid composition was shown to be higher than 50% in all powders, and the ratio of the polyunsaturated fatty acid composition to the saturated fatty acid composition was found to be the same (2.07) for HLB 11 and HLB 16.