• 제목/요약/키워드: hemB

검색결과 36건 처리시간 0.028초

Study for the Development of Fe-NbC Composites by Advanced PM Techniques

  • Gordo, E.;Gomez, B.;Gonzalez, R.;Ruiz-Navas, E.M.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.118-119
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    • 2006
  • The development of Fe-based metal matrix composites (MMCs) with high content of hard phase has been approached by combining the use of advanced powder metallurgy techniques like high-energy milling (HEM), cold isostatic pressing (CIP) and vacuum sinterings. A 30% vol. of NbC particles was mixed with Fe powder by HEM in a planetary mill during 10h, characteristing the powder by the observation of morphology and microstructure by scanning electron microscopy (SEM). After of sintering process the variation of density, hardness,carbon content and the microstructural changes observed, permits to find the optimal conditions of processing. Afterwards, a heat treatment study was performed to study the hardenability of the composite.

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유기성자원의 퇴비원료로 활용 가능성 평가방법 개발 (Development of Method for Possibility Assessment on Organic Resources for Using Raw Material of Compost)

  • 임동규;이승환;성기석;소규호;신중두;이정택
    • 한국환경농학회지
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    • 제25권1호
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    • pp.77-84
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    • 2006
  • 본 연구는 다양한 종류의 유기성자원 중에서 퇴비원료로의 활용 가능성이 충분하고 퇴비로 제조되어 농지에 시용하였을 때 유해성분이 적은 자원을 선별하기 위해 현재 비료관리법상 퇴비원료기준에 규제하고 있는 유기물함량과 중금속(8성분)에 유기화합물(HEM, PAHs)과 Bioassay(Microtox 생물검정법)을 추가하여 규제기준으로 활용 가능성을 검토하기 위해 $'04{\sim}'05$년(2년) 전국의 유기성자원 16종, 62점을 무작위로 선정하여 분석하였다. 시험재료의 유기물함량은 $65.3{\sim}98.0%$로서 기준치인 60% 이상을 크게 상회하였고, 전 질소 함량과 인산함량은 퇴비원료로서 질소 및 인산성분의 공급을 기대할 수 있을 것으로 생각되었다. 중금속의 경우 섬유오니가 Cr, Ni 및 As에서, 식품오니 및 피혁오니는 Ni 함량에서 퇴비원료의 기준치를 초과하여 퇴비원료로 사용이 곤란하였고, 나머지 성분함량들은 모두 기준치보다 낮았다. HEM 함량은 섬유오니가 $113mg\;kg^{-1}$으로 다른 재료에 비해 상당히 높았으며, PAHs 함량은 제지오니에서 $3,462ug\;kg^{-1}$으로 가장 높았고 그 다음은 피혁오니>중소도시 하수오니 순으로 낮았다. PAHs 성분별 분포는 naphthalene, phenanthrene, pyrene, fluoroanthene, acenaphthene이 다른 화합물들보다 많았다. Microtox분석에서 $EC_{50}$값은 피혁오니에서 가장 낮았고, 제약오니<제지오니<공단지역 하수오니<섬유오니 등의 순으로 낮아졌다. 각 분석치 항목 간의 상관관계는 HEM이 Zn, Cu, Ni과 99% 및 Cd와 95% 수준에서, Microtox $EC^{-1}$ 값은 Hg과 HEM에서 95% 수준에서 유의성을 보였다. 현재 우리나라에서 유기성자원의 퇴비원료로 활용에 대한 기준은 유기물함량과 중금속(8성분: Zn, Cu, Cr, Pb, Ni, Cd, As, Hg)으로 규제하고 있으나, 일반성분(B) 및 중금속(Co, Mo, Se)을 비롯하여 유해화합물(HEM, PAHs, PCBs 등) 및 생물검정법(Microtox 등)에 대한 추가적인 보완연구를 통해 퇴비원료로 활용 가능성 여부를 평가할 수 선별체계(일반성분$\Rightarrow$중금속$\Rightarrow$유기화합물$\Rightarrow$Bioassay) 및 각 선별 체계별 활용기준 항목에 대한 규제기준이 설정된 후 이들의 각 성분함량을 통과하고 최종 비효시험(포장)을 마친 경우에는, 유용한 유기성자원의 농업적 활용으로 안전한 작물재배 및 농업환경을 보전할 수 있다고 생각된다.

영왕비의 진주낭자 도안을 응용한 니트웨어 디자인 연구 (A Study on Knitwear Design Using the Pattern of Queen Yeong's Pearl Pouch)

  • 최정
    • 한국의류산업학회지
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    • 제16권4호
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    • pp.532-542
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    • 2014
  • This study developed a practical knitwear design with applying the pattern of Queen Yeong's pearl pouch. The ume flower pattern of pearl pouch was simplified to be one repeat pattern, and four simulated knit pattern samples of G-A, G-B, R-A, and R-Bwere made with cable, cross, and two background colors of gray and red using Texpro V.11.0. The items of design application were selected after an interview with a panel of university students in their twenties and knit samples were produced by hand knitting. The small sized G-A for the partial ornament of hat, sweater, skirt, kitchenware case and accessories; the long sized G-B for the tuck of sleeves, hem of skirt and one-piece dress, partial ornament of sweater, scarf, and curtain decoration: the small sized R-A was preferred for point ornament of pouch, boots, hat, partial ornament of children's fashion products and accessories: the long sized R-B for table runner, leg warmer, tuck of sleeves, skirt hem, necktie, and scarf. The knit samples were formulated with partial ornaments attached on dress and props or connected each other. Colors of pastel and navy were also presented to meet the demands of panels. The study placed a limit on the slight difference between the simulation samples and knit samples due to the characteristics of threads and hand tension. The color variation for multiple coordination and activation to reduce the piece rate for young customers remains to be discussed in the near future.

$2{\times}2$배열 피드혼 안테나용 모노 펄스 피드 설계 (Design of a Monopulse Feed for $2{\times}2$ Array Feed horn Antenna)

  • 김원섭
    • 대한전자공학회논문지TC
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    • 제45권1호
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    • pp.91-96
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    • 2008
  • 본 논문에서는 3중 모드를 형성하는 $2{\times}2$배열 피드혼 안테나용 모노 펄스 피드를 설계 제작하고 복사 특성을 고찰하였다. 단일 피드의 경우 이득은 8.25dB의 값을 가지며,. 변환부에서 공기 중으로 연결되는 부위에 전계면으로 확장되는 구조를 갖게 함으로써 이득은 증가하고 구형 도파관과 공기 중의 반사는 저하시켰다. 급전 피드 port1과 port2는 수직으로 위치하여 개구부 혼의 두께를 얇게 함으로써 격리도는 -25dB이하의 특성을 만족하며 높은 주파수일수록 격리도는 향상됨을 확인하였다. port1과 port3은 수평으로 위치하여 전기장의 분포가 병렬로 연결되기 때문에 전기장의 결합은 적게 일어나지만 자기장의 결합이 나타나기 때문에 port1과 port2와의 격리도 보다는 최저 2dB에서 최대 6dB 향상된다. port1과 port4는 구조적으로 직접 결합은 아주 적은 양만 발생하지만, port2와 port3의 영향으로 -35dB이하가 됨을 확인 할 수 있었다.

초고출력 안테나 시스템 급전용 좁은 빔폭의 다중모드 혼 안테나 설계에 관한 연구 (A Study on Design of Narrow Beamwidth Multimode Feed Horn Antenna for High Power Microwave Antenna System)

  • 이상흔;안지환;윤영중;소준호
    • 한국전자파학회:학술대회논문집
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    • 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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    • pp.361-366
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    • 2005
  • In this paper, a modified multimode hem antenna is designed to have 142 mm horn aperture radius and 921 mm length in order to be safe under 100 MW peak pulse power at 3 cm wave length through breakdown phenomenon study that threshold field strengths for the air breakdown phenomena is decided to be 3.78 MV/m. The proposed antenna is measured gain over 27 dBi and the -25 dB beam width of 29$^{\circ}$ in vertical plane.

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세균의 지방산 생합성 효소 (Enoyl-Acyl Carrier Protein Reductase, FabI)를 저해하는 새로운 항균물질의 스크리닝 (Screening of New Antibiotics Inhibiting Bacterial Enoyl-Acyl Carrier Protein Reductase (Fabl))

  • 곽진환
    • 약학회지
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    • 제46권1호
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    • pp.24-29
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    • 2002
  • Enoyl-Acyl Carrier Protein Reductase (Fabl) of bacteria is hem as an important target for new antibacterial drugs and plays a determinant role in completing cycles of elongation in type-H fatty acid synthase system. In this study, a fabI gene from Staphylococcus aureus 6538p cloned in pET-l4b vector and FabI protein was over-produced in Escherichaia coli BL2l (DE3). $NH_2$-terminal His-tagged FabI protein was purified by nickel-nitrilotriacetic acid (Ni-NTA) metalaffinity chromatography Purified 6xHis-tagged FabI showed a catalytic activity on tram - 2 - octenoyl - N -acethlcysteamine by utilizing NADPH as a cofactor. For the discovery of new FabI inhibitors from chemical libraries, a target-oriented screening system using a 96-well plate was developed. About 10,000 chemical libraries from Korea Chemical Bank wore tested in this screening system, and 26 chemicals (0.25%) among them showed an inhibitory activity against FabI enzyme. This result showed that a new screening system can be used for the discovery of new FabI inhibitors.

남성 싱글플리티드 팬츠 패턴비교분석 및 가상착의평가 (Comparative Analysis of Pants Pattern and Virtual Appearance Evaluation for Men's Single-pleated Pants)

  • 홍은희;김경아;어미경
    • 한국의상디자인학회지
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    • 제17권1호
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    • pp.105-115
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    • 2015
  • This study aims to compare the ease of men's single-pleated pants patterns, and to analyze the fit and appearance through the 3D virtual garment system. The researchers selected five(four educational materials and one industrial pattern) slim-fit single-pleated pants which is the current fashion trend in menswear. The CLO 3D Modelist program was utilized to carry out the appearance evaluation through virtual wearing, opacity, and clothing pressure. The results showed that D pants had the greatest ease on the waist circumference, while C pants had the least ease. The E pants had the greatest ease on the hip circumference, then B pants and C pants showed less ease. Also, the E pants had the longest on the pants length, then D pants showed the shortest. In the appearance evaluation, A pants received the most favorable results, followed by D, B, E, and C pants, in descending order. The clothing pressure appeared to be mainly red on the waist, crotch, and hem in all pants, so the clothing pressure was high. From the results, we can understand that each of the 5 single-pleated pants patterns has different ease amount and silhouette.

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진바지의 착용 후 부위별 피로도에 관한 연구 (Fatigue Phenomenon of Mechanical Properties in Jean Slacks by the after Wearing)

  • 이창미;김태규;권오경
    • 한국의류학회지
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    • 제22권2호
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    • pp.257-266
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    • 1998
  • This study was conducted to examine the changes of the mechanical properties of the position in jean slacks during the wear, previously used for the wearing test, which were subjected to repeated tensile-shearing deformation using a simulated fatigue tester has been investigated and compared, by calculating both mechanical properties and hand value(HV) of these fabrics with KES-F system and the by obtaining the THV through these calculated properties. The results are as follows. 1. The fatigue phenomenon of mechanical properties was the LT, 2H B, 2HBS, MMD, SMD, RC values increased, elasticity values of tensile, bending and shearing properties, such as B, G and compression properties LC, WC were reduced. It was shown, then, that those fabrics lost their elasticity and became flexible and soft with the increase of fatigue. 2. The hand value and THV; except anterior knee from all part of KOSHI, NUMERI, FUKURAMI was decreased. 3. The fatigue phenomenon of hand value was different on the position of clothing; on the position of hip, rate of B, G smaller than other parts and KOSHI was decreased, on the part of anterior thigh was FUKURAMI was increased, on the anterior knee RC, NUMERI, THV was increased, on the posterior knee was 2HB, 2HG, 2HGS showed increasedgreater than any other part and on the hem of back, MMD was increased, but NUMERI was decreased. 4. The changing process of mechanical properties in the simulation testing by the fatigue tester has similar tendency to that of the wearing tester. It is concluded that this testing method is useful to predict the fatigue phenomena of fabrics caused by wearing.

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견직물의 광열화 거동 (Photo-Degradation Behavior of Silk Fabrics)

  • 이학정;권영숙;장정대;이상준;조현혹
    • 한국염색가공학회지
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    • 제18권6호
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    • pp.37-42
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    • 2006
  • Researches to preserve and restore the remaining fabrics as costume heritages have been carried out. In this study, in order to artificially restore an excavated silk fabrics, degummed silk fabrics and safflower dyed silk fabrics were prepared for an experiment. These fabrics were photo-degraded by the Xenon arc beam to have various strength retention(100%, 80%, 60%, 40%, 20%). The fine structure and physical properties of Xenon arc treated fabrics were investigated with various techniques such as tensile test, weight loss, wide-angle X-ray diffraction, yellowness, color, SEM etc. Tensile strength and the crystal diffraction intensity of silk fabrics decreased as Xenon arc hem treatment time increased. Weight loss increased slightly. Strength retention was decreased as the Xenon arc beam treatment time goes by. (Yellowness of the undyed silk fabrics and $L^*$ of the dyed silk fabrics increased. Whiteness of the undyed silk fabrics and $b^* of the dyed silk fabrics decreased.) SEM results of the silk fabrics treated Xenon arc beam show that surface was a little damaged.

Potential Application of the Recombinant Escherichia coli-Synthesized Heme as a Bioavailable Iron Source

  • Kwon, Oh-Hee;Kim, Su-Sie;Hahm, Dae-Hyun;Lee, Sang-Yup;Kim, Pil
    • Journal of Microbiology and Biotechnology
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    • 제19권6호
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    • pp.604-609
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    • 2009
  • To investigate the potential use of microbial heme as an iron source, recombinant Escherichia coli coexpressing ALA synthase (HemA) as well as the NADP-dependent malic enzyme (MaeB) and dicarboxylic acid transporter (DctA) were cultured. The typical red pigment extracted from the recombinant E. coli after 38 h showed highest absorbance at 407 nm, and the amount of iron in 38.4 mg of microbial heme extract derived from 6-1 fermentation broth was 4.1 mg. To determine the commercial potential of the recombinant E.coli-synthesized iron-associated heme as an iron source, mice were fed the iron-free provender with the microbial heme extract. The average body weight reduction of mice fed non-iron provender was 2.3%, whereas no detectable weight loss was evident in mice fed microbial heme addition after 15 days. The heme content of the blood from microbial heme fed mice was 4.2 mg/ml whereas that of controls was 2.4 mg/ml, which implies that the microbial heme could be available for use as an animal iron source.