• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2005년도 춘계학술강연 및 발표대회강연 및 발표논문 초록집
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• pp.15-16
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• 2005

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.1193-1194
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• 2011

• 한국식품영양과학회지
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• 제43권7호
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• pp.1042-1047
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• 2014

양갱 재료의 주재료인 팥을 토마토 분말로 대체하고 설탕을 저칼로리 감미료인 올리고당으로 대체하여 양갱을 제조한 후 품질특성을 평가하였다. 토마토 양갱의 수분함량은 45.89~33.64%의 함량을 나타내었으며, 대조군에서 가장높은 함량을 나타내었다. pH는 3.96~6.24로 토마토 분말첨가에 의해 pH가 유의적으로 감소하였다. 색도 측정 결과, L 값은 토마토 분말 20% 첨가군에서 가장 높았으며 a 값은 20% 첨가군을 제외하고 토마토 분말 첨가량이 증가할수록 유의적으로 증가하는 경향을 나타내었다. b 값은 10% 첨가군까지 유의적으로 증가하는 경향을 보이다가 20% 첨가군에서 다시 감소하였다. 물성 측정 결과, 토마토 분말의 첨가가 양갱의 경도, 응집성, 점착성, 씹힘성을 유의적으로 감소시키는 것으로 확인되었다. 당도 측정 결과, 대조군의 당도가 5.16으로 가장 높았고 토마토 양갱은 4.46~4.92의 당도를 나타내어 토마토 분말의 첨가가 양갱의 당도를 유의적으로 감소시켰다. DPPH 라디칼 소거능을 측정을 통한 항산화 활성 측정 결과 토마토 분말 첨가에 의해 항산화 활성이 유의적으로 증가하였으나 15% 및 20% 첨가구에서는 유의적 차이를 보이지 않았다. 관능평가 결과, 질감을 제외한 색, 향, 단맛, 신맛, 전반적인 기호도 평가에서 토마토 분말 5% 및 10% 첨가군에서 높은 기호도를 나타내었다. 따라서 관능적 기호도 및 항산화 활성 등의 효과 면에서 토마토 분말 10% 첨가가 바람직할 것으로 사료되나 산업화를 위해서는 기호도 향상을 위한 좀 더 다양한 연구를 더 진행해야 할 것이다.

• 한국분말재료학회지
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• 제19권4호
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• pp.291-296
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• 2012

In the present work, Al-$B_4C$ composite powders were fabricated using a mechanical milling process and its milling behaviors and mechanical properties as functions of $B_4C$ sizes ( $100{\mu}m$, 500 nm and 50 nm) and concentrations (1, 3 and 10 wt.%) were investigated. For achieving it, composite powders and their compacts were fabricated using a planetary ball mill machine and magnetic pulse compaction technology. Al-$B_4C$ composite powders represent the most uniform dispersion at a milling speed of 200 rpm and a milling time of 240 minutes. Also, the smaller $B_4C$ particles were presented, the more excellent compositing characteristics are exhibited. In particular, in the case of the 50 nm $B_4C$ added compact, it showed the highest values of compaction density and hardness compared with the conditions of $100{\mu}m$ and 500 nm additions, leading to the enhancement its mechanical properties.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1203-1204
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• 2006

Cu-$TiB_2$ nanocomposite powders were synthesized by combining high-energy ball-milling of Cu-Ti-B mixtures and subsequent self-propagating high temperature synthesis (SHS). Cu-40wt.%$TiB_2$ powders were produced by SHS reaction and ball-milled. The milled SHS powder was mixed with Cu powders by ball milling to produce Cu-2.5wt.%$TiB_2$ composites. $TiB_2$ particles less than 250nm were formed in the copper matrix after SHS-reaction. The releative density, electrical conductivity and hardness of specimens sintered at $650-750^{\circ}C$ were nearly 98%, 83%IACS and 71HRB, respectively. After heat treatment at 850 to $950^{\circ}C$ for 2 hours under Ar atmosphere, hardness was descedned by 15%. Our Cu-$TiB_2$ composite showed good thermal stability at eleveated temperature.

• 한국분말재료학회지
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• 제23권6호
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• pp.447-452
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• 2016

Neodymium-iron-boron (Nd-Fe-B) sintered magnets have excellent magnetic properties such as the remanence, coercive force, and the maximum energy product compared to other hard magnetic materials. The coercive force of Nd-Fe-B sintered magnets is improved by the addition of heavy rare earth elements such as dysprosium and terbium instead of neodymium. Then, the magnetocrystalline anisotropy of Nd-Fe-B sintered magnets increases. However, additional elements have increased the production cost of Nd-Fe-B sintered magnets. Hence, a study on the control of the microstructure of Nd-Fe-B magnets is being conducted. As the coercive force of magnets improves, the grain size of the $Nd_2Fe_{14}B$ grain is close to 300 nm because they are nucleation-type magnets. In this study, fine particles of Nd-Fe-B are prepared with various grinding energies in the pulverization process used for preparing sintered magnets, and the microstructure and magnetic properties of the magnets are investigated.

• 한국분말재료학회지
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• 제26권2호
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• pp.156-165
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• 2019

Over the last decade, the next generation's ultra-high-temperature materials as an alternative to Nickel-based superalloys have been highlighted. Ultra-high-temperature materials based on refractory metals are one of several potential candidates. In particular, molybdenum alloys with small amounts of silicon and boron (Mo-Si-B alloys) have superior properties at high temperature. However, research related to Mo-Si-B alloys were mainly conducted by several developed countries but garnered little interest in Korea. Therefore, in this review paper, we introduce the development history of Mo-Si-B alloys briefly and discuss the properties, particularly the mechanical and oxidation properties of Mo-Si-B alloys. We also introduce the latest research trends of Mo-Si-B alloys based on the research paper. Finally, for domestic research related to this field, we explain why Mo-Si-B alloys should be developed and suggest the potential directions for Mo-Si-B alloys research.

• 한국산학기술학회논문지
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• 제6권6호
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• pp.468-472
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• 2005

유리병의 제조에 있어서 유리 융체가 금형 벽면에 부착하는 것을 방지하기 위하여 성형할 때마다 금형 내벽면을 윤활제로 도포하는 공정이 있다. 금형 벽면을 통기성이 있는 다공질 소결체로 제조하면 도포공정을 생략할 수 있다. 따라서 본 연구에서는 스테인리스 중에서 내열${\cdot}$내마모 특성이 가장 우수한 310L계 조대 분말($-150{\mu}m$) 및 420J2 계 미세 분말($40{\~}50{\mu}m$)을 사용, 유리 금형용 내벽면 재로서 가장 적합한 다공질 소결체(소결체의 밀도: $85{\~}90\%$)를 제작하기 위하여 성형압력, 소결 분위기, 소결온도 및 시간을 변화시켜 다음과 같은 결과를 얻었다. (1) 고상 소결로서는 입자 크기가 큰 310L분말을 가지고는 어느 경우에 있어서나, 목적하는 소결 밀도를 얻을 수 없었다. (2) $2ton/cm^2$의 성형압력으로 성형한 실형상 성형체를 양산용 진공($1300^{\circ}C$, 2시간) 소결로에서 소결한 결과, 소결체의 밀도는 $310L+0.03\%B$, 420J2, 420J2+(0.03, 0.06)$\%$B에서 각각 6.2(79$\%$), 6.6(86$\%$), 7.3(95$\%$), $7.6(99\%)g/cm^3$로 나타났다. 따라서, 420J2계 분말(저압성형) 및 310L+0.03$\%$B(고압성형)분말을 사용하여 진공 중 소결하면 목적하는 통기도를 가진 소결체를 제작할 수 있다는 것을 알았다.

• Journal of Nutrition and Health
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• 제37권7호
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• pp.515-524
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• 2004

This study was performed to investigate effect of dried powders and ethanol extracts of garlic flesh and peel on lipid metabolism and antithrombogenic capacity in 16-month-old rats. Forty Sprague-Dawley male rats weighing 618.1$\pm$6.5 g were blocked into five groups according to body weight and raised for 3 months with control and experimental diets containing 5% (w/w) of dried powders of garlic flesh or peel, or ethanol extracts from equal amount of each dried powder and control diet. Plasma and liver total lipids, triglyceride and total cholesterol, and plasma HDL-cholesterol, throm-boxane $B_2$ (TX $B_2$), 6-keto-prostaglandin $F_{1a}$ (6-keto-PG $F_{1a}$) concentrations were measured. Total, insoluble and soluble dietary fibers contents were highest in peel powder followed by fresh powder, and those in ethanol extracts of flesh and peel, especially soluble, very low. Plasma and liver total lipids, triglyceride, and total cholesterol concentrations were lower in all the garlic experimental groups compared to Especially, flesh and peel powder lowered plasma total lipids, triglyceride and total cholesterol concentrations markedly, and flesh powder and flesh ethanol extract lowered liver total lipids, triglyceride and total cholesterol concentration remarkably. Plasma TX $B_2$ concentrations in garlic experimental groups were lower than that of control group, and 6-keto-PG $F_{1a}$ concentrations. In garlic experimental groups were higher than that of control group. Flesh ethanol extract group showed the lowest TX $B_2$ and the highest 6-keto-PG $F_{1a}$ concentrations among experimental groups, so TX $B_2$/6-keto-PG $F_{1a}$ ratio in flesh ethanol extract group was significantly lower than that of control group. Moreover, clotting time was significantly increased in flesh ethanol extract group as compared to control group. In conclusion, intakes of dried powders and ethanol extracts of garlic flesh and peel were effective in lowering lipid levels of liver and plasma. And also flesh ethanol extract diet was most effective in antithrombogenic activity among garlic experimental groups as TX $B_2$/6-keto-PG $F_{1a}$ ratio in flesh ethanol extract group was significantly lower and clotting time was significantly increased in this group as compared to control group.ntrol group.

• 동아시아식생활학회지
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• 제17권6호
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• pp.894-902
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• 2007

This study was performed to observe the quality characteristics of Eunhakong dasik and Small Black Soybean dasik prepared with different addition rates of chlorella powder. For the Hunter's color values, the $L^*,\;a^*,\;and\;b^*$ values of both dasiks decreased with the addition of chlorella powder. The cohesiveness and gumminess of both dasiks were not dependant on the chlorella powder additions. However, the hardness of the Eunhakong dasik with 8% chlorella powder increased. The springiness and brittleness of the Eunhakong dasik had a tendency to decrease as the addition rate of the chlorella powder increased. In terms of sensory quality, both the dasiks were improved by the addition of 4% chlorella powder. Therefore, in subsequent examinations, the chemical characteristics of both dasiks were determined for the 4% addition of chlorella powder. The moisture and crude lipid contents of both dasiks were not influenced by the addition of chlorella powder. Carbohydrate content was highest in the Eunhakong dasik with 0% chlorella powder, and in the Small Black Soybean dasik with 4% chlorella powder. Conversely, crude protein content was highest in the Eunhakong dasik with 4% chlorella powder, and in the Small Black Soybean dasik with 0% chlorella powder. The crude lipid content of the Small Black Soybean dasik with 4% chlorella powder was lower than that of the control without chlorella powder. For mineral content, the K content of both dasiks was not influenced by the addition of chlorella powder. The Ca, Mg, and P contents of both dasiks with 4% chlorella powder, respectively, were lower than those of the dasik with 0% chlorella powder. Finally, the total amino acid content of the Eunhakong dasik tended to decrease, while that of the Small Black Soybean dasik incrased, with the 4% addition of chlorella powder.