• Title/Summary/Keyword: B powder

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공구강에 형성된 복합(B+C+N) 확산층의 특성 연구 (Characterization of the complex(B+C+N) Diffusion Layers Formed on Tool Steels)

  • 이종훈;유위도;임영목;권기현
    • 연구논문집
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    • 통권33호
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    • pp.175-182
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    • 2003
  • In this study, the wear resistance of the complex powder diffusion treated KS STD 61 has been investigatived. KS STD 61 tool steel was pretreated in quenching and tempering processes to obtain the tempered martensitic microstructure. The samples were packed with complex powder in steel pot($\Phi$90x60mm) and heated in a box furnace. the complex powder diffusion treatment are carried out at $540^{\circ}C$, $520^{\circ}C$, $500^{\circ}C$ for 40min, 1.5hr and 2.5hr. The microstructure, microhardness, wear resistance, and coating layer thickness of the complex powder diffusion treated samples were investigation. The weight loss of as heat treated sample was 0.4mg and that of the complex powder treated at $540^{\circ}C$ for 2.5hr was 0.17mg. These result means that the wear resistance of tool steels can be easily improved by the powder diffusion process at conventional tempering treatment temperature.

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Sensory Profiles of Protein-Fortified Kefir prepared Using Edible Insects (Silkworm Pupae, Bombyx mori) : A Preliminary Study

  • Kim, Young-Ji;Chon, Jung-Whan;Song, Kwang-Young;Kim, Dong-Hyeon;Kim, Hyunsook;Seo, Kun-Ho
    • Journal of Dairy Science and Biotechnology
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    • 제35권4호
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    • pp.262-265
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    • 2017
  • Bombyx mori (silkworm pupae) is a unique and biologically significant insect, which is a recognized source of high quality protein that provides all the essential amino acids required for human health. Recently, many studies have focused on various biomedical applications of B. mori proteins. The purpose of this study was to manufacture protein-fortified kefir containing different concentrations of B. mori powder according to pH and sensory evaluations. The value of the protein-fortified kefir increased but the pH decreased with increasing incubation time, indicating that the amount of B. mori powder did not affect and pH. Addition of B. mori powder also did not affect the sensory properties of overall acceptability, texture, and color compared to control group without addition of B. mori powder. However, flavor and taste were affected by increasing the amounts of B. mori powder, with a significant difference in both flavor and taste between the control and treated groups (both p<0.05). There was no significant difference in overall acceptability, texture, and color. Further studies are needed for producing kefir as a dietary supplement utilizing the functional properties of B. mori.

연근가루를 첨가한 설기떡의 품질 특성 (Quality Characteristics of Sulgitteok Added with Lotus Root Powder)

  • 윤숙자;최봉순
    • 한국식품조리과학회지
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    • 제24권4호
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    • pp.431-438
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    • 2008
  • This study examined the quality characteristics of Sulgitteok samples prepared with different ratios of lotus root powder over 4 days of storage. The moisture contents of the lotus root powder-containing samples ranged from 35.39 to 37.31% and that of the Sulgitteok without lotus root powder control was 35.92%. The results showed that the various samples had the inconsistent changes during the storage period. As the content of lotus root powder increased, the L-values of samples decreased and the a- and b-values increased. However, their L-, a- and b-values did not show large differences with storage. When compared to the control, the hardness, gumminess, and chewiness of samples slowly increased as the amount of lotus root powder increased. Springiness and cohesiveness decreased according to the amount of added lotus root powder. And increasing amounts of lotus root powder and storage time resulted in greater reductions in adhesiveness. In addition, increasing storage time caused cohesiveness to decrease and springiness to increase. The sensory evaluation results showed that the 20% lotus root Sulgitteok received the highest scores, therefore, this samples was deemed superior.

모링가 잎 분말을 이용하여 제조한 국수의 품질 특성 (Quality Characteristics of Noodles added with Moringa oleifera Leaf Powder)

  • 김선영;정장호
    • 동아시아식생활학회지
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    • 제27권3호
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    • pp.321-331
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    • 2017
  • This study investigated the quality of noodles added with Moringa oleifera leaf powder. Noodles were prepared at ratios of 0% (control), 2%, 4%, 6%, and 8% (w/w) Moringa oleifera leaf powder based on flour weight. Land a value of uncooked noodles decreased while b value increased (p<0.001) with the addition of Moringa oleifera leaf powder. Further, L and a value of the cooked noodles decreased while b value increased (p<0.001). Weight, volume, and water absorption of cooked noodles increased with increasing addition of Moringa oleifera leaf powder (p<0.001). pH value of soups decreased while turbidity of soups increased (p<0.001) as amount Moringa oleifera leaf powder increased. Hardness (p<0.001), cohesiveness (p<0.001), chewiness (p<0.001), and adhesiveness (p<0.05) increased significantly while springiness decreased (p<0.01) with increasing addition of Moringa oliefera leaf powder. Total polyphenol content, total flavonoid content, and DPPH free radical scavenging activity increased with increasing addition of Moringa oleifera leaf powder (p<0.001). Noodle prepared with 4% Moringa oleifera leaf powder was the most preferred in terms of overall preference.

산지별 고초균 발효누에의 이화학적 특성 및 생리활성 (Biological Activity and Biochemical Properties of Water Extracts from Bacillus subtilis-fermented Silkworm (Bombyx mori L.) Powder by Origin)

  • 김태훈;안희영;김영완;심소연;서권일;조영수
    • 생명과학회지
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    • 제27권12호
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    • pp.1470-1478
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    • 2017
  • 본 연구는 건강기능성 식품의 소재로서 활용하기 위해 부안, 남원 및 보은의 산지별 누에분말을 단백질 분해능이 뛰어난 Bacillus subtilis KACC 91157 균주로 발효시켜 제조한 발효누에 추출물의 이화학적 특성 및 생리활성을 평가하였다. 구성 아미노산 함량은 부안 누에군(BU)에서 가장 높았으나, 발효 후에는 보은 발효누에군(BBO)에서 가장 높은 함량을 보였다. 미네랄 함량은 K, Ca, Mg 순으로 함유되어 있었으나, Na가 가장 높은 미네랄 함량의 증가율을 보였다. DPPH를 통한 자유라디칼 소거능과 혈전용해 효소활성은 발효 전에 비하여 발효누에군에서 높게 나타났으며, 특히 BBO군에서 가장 높은 활성을 보였다. 전립선암 세포(LNcaP)와 유방암 세포(MCF-7) 성장 저해능은 BBO군에서 가장 높게 나타났으며 LPS 처리 RAW 264.7세포의 NO생성 억제활성 역시 BBO군에서 가장 높게 나타났다. 이와 같이 산지별 고초균 발효누에 추출물을 비교해본 결과 보은 누에가 건강기능성 식품의 소재로서 활용할 가치가 높은 것으로 사료된다.

금속분말이 첨가된 $MgB_2$ 선재의 제조 및 특성 (Fabrication of $MgB_2$ tape with metal powder addition)

  • 고재웅;유재무;김영국;정국채;유상임
    • 한국초전도ㆍ저온공학회논문지
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    • 제8권1호
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    • pp.1-4
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    • 2006
  • The $MgB_2$ tapes with several metal powder addition were fabricated by PIT method with or without heat treatment. The $J_c$ value of $5.600A/cm^2$ and $16.000A/cm^2$ at 4.2 K and 5 T were obtained for the $MgB_2$ tape and 10 vol % of Cu added $MgB_2$ tape without heat treatment respectively. The $J_c$ value of $8.000A/cm^2$ and $35,000A/cm^2$ at 4.2 K and 5 T were obtained for the $MgB_2$ tape and 10 vol. % of Al added $MgB_2$ tape with heat treatment, respectively. The $J_c-B$ curve shows enhancement in $J_c$ under magnetic field. which suggests enhancement in workability and grain connectivity with several metal powder addition.

Fe_3B+Nd_2Fe_{14}B Spring magnet분말 압분체의 Exchange Decoupling (Exchange Decoupling Of $Fe_3$Fe_3B+Nd_2Fe_{14}B Spring Magnet Powder Compact)

  • 한종수;양충진;박언병
    • 한국자기학회지
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    • 제11권5호
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    • pp.232-238
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    • 2001
  • Nano결정립 N $d_2$F $e_{14}$B+F $e_3$B 복합상 자성 압분체의 탈자화 현상을 자기특성 변화 및 $\delta$M측정에 의해 분석하였다. 초기 조성 N $d_4$F $e_{73.5}$ $Co_3$H $f_{0.5}$G $a_{0.5}$ $B_{18.5}$의 최대자기에너지적은 리본상태에서 14 MGOe, 분말 압분체에서 6.5 MGOe로 크게 감소하였다. 이러한 현상은 복합상의 리본상태에서 존재하는 교환상호작용력이 분말 압분체에서는 나타나지 않고, 정자장 작용에 의한 탈자화로 인해 잔류자속밀도가 크게 감소한 결과이다. 이는 급냉리본(bulk) 보다 압분체상태에서 정자장 상호작용력이 교환상호작용력보다 더 크게 작용하는 결과로 해석된다. 또한, 자성체 리본을 분쇄하는 과정에서 발생한 응력도 자기특성을 감소시키는 요소임을 확인하였다.하였다.하였다.

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