• 제목/요약/키워드: nano materials

검색결과 4,501건 처리시간 0.043초

Strength and durability study on cement mortar containing nano materials

  • Ashok, M.;Parande, A.K.;Jayabalan, P.
    • Advances in nano research
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    • 제5권2호
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    • pp.99-111
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    • 2017
  • Nano particles have been gaining increasing attention and applied in many fields to fabricate new materials with novel functions due to their unique physical and chemical properties. In the present study two nano materials, namely nano silica (NS) and nano clay metakaolin (NMK) were partially replaced with ordinary Portland cement (OPC). The replacement level was varied from 0.5 to 2.0% in OPC and blended in cement mortar with a water cement ratio of 0.40. Mechanical property studies and durability experiments such as compressive strength, tensile strength, water absorption, depth of chloride penetration test. Nano silica was synthesized from rice husk ash and analyze the size using particle size analyzer. The results indicate that the compressive and tensile strength of the cement mortars containing nano materials were higher strength compared to the plain mortar with the same water cement ratio.

Synthesis and Dispersion Stabilization of Indium Tin Oxide Nanopowders by Coprecipitation and Sol-Gel Method for Transparent and Conductive Films

  • Cho, Young-Sang;Hong, Jeong-Jin;Kim, Young Kuk;Chung, Kook Chae;Choi, Chul Jin
    • 대한금속재료학회지
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    • 제48권9호
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    • pp.831-841
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    • 2010
  • Indium tin oxide (ITO) nanopowders were synthesized by coprecipitation and the sol-gel method to prepare a stable dispersion of ITO nano-colloid for antistatic coating of a display panel. The colloidal dispersions were prepared by attrition process with a vibratory milling apparatus using a suitable dispersant in organic solvent. The ITO coating solution was spin-coated on a glass panel followed by the deposition of partially hydrolyzed alkyl silicate as an over-coat layer. The double-layered coating films were characterized by measuring the sheet resistance and reflectance spectrum for antistatic and antireflective properties.

나노사출성형용 스탬퍼 제작을 위한 Electron beam lithography 패터닝 연구 (Electron beam lithography patterning research for stamper fabrication using nano-injection molding)

  • 엄상진;서영호;유영은;최두선;제태진;황경현
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.698-701
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    • 2005
  • We have investigated experimentally a nano patterning using electron beam lithography for the nickel stamper fabrication. Recently, DVD and Blu-ray disk(BD) have nano-scale patterns in order to increase the storage density. Specially, BD has 100nm-scale patterns which are generally fabricated by electron beam lithography. In this paper, we found optimum condition of electron-beam lithography for 100nm-scale patterning. We controlled various conditions of EHP(acceleration voltage), beam current, dose and aperture size in order to obtain optimum conditions. We used 100nm-thick PMMA layer on a silicon wafer as photoresist. We found that EHP was the most dominant factor in electron-beam lithography.

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Synthesis of Amorphous Matrix Nano-composite in Al-Cu-Mg Alloy

  • Kim, Kang Cheol;Park, Sung Hyun;Na, Min Young;Kim, Won Tae;Kim, Do Hyang
    • Applied Microscopy
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    • 제44권3호
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    • pp.105-109
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    • 2014
  • The microstructure of as-quenched $Al_{70}Cu_{18}Mg_{12}$ alloy has been investigated in detail using transmission electron microscopy. Al nano-crystals about 5 nm with a high density are distributed in the amorphous matrix, indicating amorphous matrix nano-composite can be synthesized in Al-Cu-Mg alloy. The high density of Al nano-crystals indicates very high nucleation rate and sluggish growth rate during crystallization possibly due to limited diffusion rate of solute atoms of Cu and Mg during solute partitioning. The result of hardness measurement shows that the mechanical properties can be improved by designing a nano-composite structure where nanometer scale crystals are embedded in the amorphous matrix.