• 제목/요약/키워드: nano-fiber

검색결과 442건 처리시간 0.035초

Field emission display with catalysis cathode film material for graphite nano fiber

  • Kageyama, Kagehiro;Kojima, Tomoaki;Hirakawa, Masaaki;Sasaki, Takaei
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.146-149
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    • 2006
  • We developed new FED cathode film material that has catalysis function for graphite nano fiber. Using the cathode film with catalyst, we can simplify the FED process. It is composed of Cr, Fe-Ni catalyst. Fabricating FED panel with the film, we confirmed good emission performance of the panel.

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분자량이 조절된 폴리카보실란으로부터 제조한 SiC Fiber의 특성분석 (Characterization of SiC Fiber Derived from Polycarbosilanes with Controlled Molecular Weight)

  • 신동근;류도형;김영희;김형래;박홍식;김현이
    • 한국세라믹학회지
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    • 제42권8호
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    • pp.593-598
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    • 2005
  • Polycarbosilane was synthesized by the Kumada rearrangement of polydimethylsilane in the presence of zeolite (ZSM-5) as a catalyst at $350^{\circ}C$. The prepared polycarbosilane had very low molecular weight ($M_w=500$), so that it was not suitable to fabricate SiC fiber by melt spinning. Further polymerization of PCS was conducted around $400^{\circ}C$ to obtain spinnable polycarbosilane. After polymerization, the polycarbosilanes were isolated by distillation according to the molecular weight distributions. The PCS with a controlled molecular weight distribution was spun into continuous polycarbosilane green fibers. The PCS green fiber was successfully transformed into silicon oxycarbide fiber. The room temperature strength of the SiC fiber was around 1.5 - 1.8 GPa. The oxidation behavior and the tensile strength after oxidation were also evaluated.

광소자 정렬용 초정밀 다축 스테이지 개발 (Development of Multi-Axis Ultra Precision Stage for Optical Alignment)

  • 정상화;이경형;김광호;차경래;김현욱;최석봉;박준호
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 추계학술대회 논문집
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    • pp.213-218
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    • 2004
  • As optical fiber communication grows, the fiber alignment become the focus of industrial attention. This greatly influence the overall production rates for the opto-electric products. We proposed multi-axis nano positioning stage for optical fiber alignment. This device has 3 DOF translation and sub nanometer resolution. This nano stage consist of 3 PZT-driven flexure stages which are stacked parallel. The displacement of it is measured with capacitance gauge and is controlled by computer-embedded main controller. The design process of flexure stage using FEM is proposed and the performance evaluation of this system is verified with experiments.

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나노 사이즈의 은 콜로이드를 이용한 PE/PP 부직포의 항균성에 관한 연구 (A study on antibacterial Property of padded PE/PP nonwovens with nano-silver colloidal solution)

  • Hwang, Yun-Hwan;Jeong, Sung-Hoon
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 2003년도 가을 학술발표회 논문집
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    • pp.241-242
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    • 2003
  • Silver has antibacterial property on bacteria of about 650 kinds and has been well known as non-toxic and non-tolerance in natural state. Recently, silver has been applied disinfection and antibacterial property to everyday life as health foods, filter, and exclusion of pollution. Nano-sized silver particle have very small size (〈10nm) and wide surface area per unit volume. PE/PP nonwovens used as back sheet or coverstock of baby diaper, adult diaper, sanitary napkin, and wiper. (omitted)

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짧은 섬유상간의 접합을 가진 Silicon Carbide Web 복합재료의 분율별 열전도 거동 (Thermal Conducting Behavior of Composites of Conjugated Short Fibrous-SiC Web with Different Filler Fraction)

  • 김태언;배진철;조광연;이동진;설용건
    • 한국세라믹학회지
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    • 제49권6호
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    • pp.549-555
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    • 2012
  • Silicon carbide(SiC) exhibits many unique properties, such as high strength, corrosion resistance, and high temperature stability. In this study, a SiC-fiber web was prepared from polycarbosilane(PCS) solution by employing the electrospinning process. Then, the SiC-fiber web was pyrolyzed at $1800^{\circ}C$ in argon atmosphere after it was subjected to a thermal curing. The SiC-fiber web (ground web)/phenolic resin (resol) composite was fabricated by hot pressing after mixing the SiC-fiber web and the phenolic resin. The SiC-fiber web composition was controlled by changing the fraction of filler (filler/binder = 9:1, 8:2, 7:3, 6:4, 5:5). Thermal conductivity measurement indicates that at the filler content of 60%, the thermal conductivity was highest, at 6.6 W/mK, due to the resulting structure formed by the filler and binder being closed-packed. Finally, the microstructure of the composites of SiC-fiber web/resin was investigated by FE-SEM, EDS, and XRD.

NITE-SiC 복합재료의 미세구조 특성에 미치는 섬유배열방향 영향 (Effects of Fiber Arrangement Direction on Microstructure Characteristics of NITE-SiC Composites)

  • 이영주;윤한기;박준수
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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    • pp.158-161
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    • 2006
  • SiC materials have been extensively studied for high temperature components in advanced energy conversion system and advanced gas turbine. However, the brittle characteristics of SiC such as law fracture toughness and law strain-to fracture impose a severe limitation on the practical applications of SiC materials. SiC/SiC composites can be considered as a promising candidate in various structural materials, because of their good fracture toughness. In this composite system, the direction of SiC fiber will give an effect to the mechanical properties. It is therefore important to control a properdirection of SiC fiber for the fabrication of high performance SiC/SiC composites. In this study, unidirection and two dimension woven structures of SiC/SiC composites were prepared starting from Tyranno SA fiber. SiC matrix was obtained by nano-powder infiltration and transient eutectoid (NITE) process. Effect of microstructure and density on the sintering temperature in NITE-SiC/SiC composites are described and discussed with the fiber direction of unidirection and two dimension woven structures.

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Dynamic Mechanical Properties of Natural Fiber/Polymer Biocomposites: The Effect of Fiber Treatment with Electron Beam

  • Han, Young-Hee;Han, Seong-Ok;Cho, Dong-Hwan;Kim, Hyung-Il
    • Macromolecular Research
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    • 제16권3호
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    • pp.253-260
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    • 2008
  • Environmentally friendly biocomposites were made using plant-based natural fibers, such as henequen and kenaf. The natural fiber reinforced polypropylene (PP) and unsaturated polyester (UP) biocomposites were examined in terms of the reinforcing effect of natural fibers on thermoplastic and thermosetting polymers. Kenaf (KE) and henequen (HQ) fibers were treated with an electron beam (EB) of 10 and 200 kGy doses, respectively, or with a 5 wt% NaOH solution. Four types of biocomposites (KE/PP, HQ/PP, KE/UP and HQ/UP) were fabricated by compression molding and each biocomposite was characterized by dynamic mechanical analysis and thermogravimetric analysis. The kenaf fiber had the larger reinforcing effect on the dynamic mechanical properties of both PP and UP biocomposites than the henequen fiber. The highest storage modulus was obtained from the biocomposite with the combination of UP matrix and 200 kGy EB treated kenaf fibers.