• Title/Summary/Keyword: molecular engineering

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Molecular Dynamics Study for Improving the Adhesion of Paint (도료의 부착성 개선을 위한 분자동역학적 연구)

  • Yang, Young-Joon;Lee, Chi-Woo
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.8
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    • pp.932-938
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    • 2007
  • The interaction between adherent molecules and gas molecules was modeled in molecular scale and simulated by the molecular dynamics method in order to understand the evaporation and removal processes of adherent molecules on metallic surface using high temperature gas flow. Methanol molecules were chosen as adherent molecules to investigate effects of adhesion quantify and gas molecular collisions because the industrial oil has too complex structures of fatty acid. The effects of adherent quantify, gas temperature and surface temperature for the evaporation rate of adherent molecules and the molecular removal mechanism were investigated and discussed in the present study. Evaporation and removal rates of adherent molecules from metallic surface calculated by the molecular dynamics method showed the similar dependence on surface temperature shown in the experimental results.

Synthesis and Characterization of Low Molecular Weight Poly(maleic anhydride-co-vinyl acetate) Copolymers

  • Yoon, Kee-Jong;Woo, Jong-Hyung;Seo, Young-Sam
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.63-64
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    • 2003
  • As a part of a research on the development of polymeric textile finishing agents, polymerization of low molecular weight copolymers containing maleic anhydride residues have been studied. In order to obtain low molecular weight poly(maleic anhydride-co-vinyl acetate) copolymers, the feed ratio of the two monomers and the concentrations of initiator and chain transfer agent were varied in the copolymerization. The copolymers were characterized using GPC, NMR, FTIR, DSC, and TGA. Copolymers with molecular weights in the range 2,150 to 6,630 have been prepared and characterized. The hydrolysis of the anhydride groups of the copolymer in water is also discussed.

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Photonic band gap fomation by mircostrip ring

  • Jang, Mi-Young;Kee, Chul-Sik;Park, Ikmo;H. Lim
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2001.11a
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    • pp.337-340
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    • 2001
  • We show that the microstrip ring with a narrow gap exhibits a photonic band gap (PBG) that is generally believed to be created by a periodic array. The discontinuity of impedance at the narrow gap induces the multiple reflections with fixed phase correlation necessary to make the PBG. We have also discussed the tuning of the PBG frequency by applying an external voltage on a varactor mounted on the gap and the applications of this PBG ring as a tunable bandstop filter and a microwave switch.

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Molecular Aligning Properties of a Dielectric Layer of Polymer-Ceramic Nanocomposite for Organic Thin-Film Transistors

  • Kim, Chi-Hwan;Kim, Sung-Jin;Yu, Chang-Jae;Lee, Sin-Doo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.1200-1203
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    • 2004
  • We investigated the molecular aligning capability of a polymer layer containing ceramic nanoparticles which can be used as a gate insulator of organic thin-film transistors (OTFTs). Because of the enhanced dielectric properties arising from the nanoparticles and molecular aligning properties of the polymer, the composite layer provides excellent mobility characteristics of the OTFTs.

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Cathode interface engineering for stable and efficient organic light-emitting diodes

  • Qiu, Yong;Duan, Lian;Li, Yang
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1199-1202
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    • 2007
  • The improvement of the electron injection is of critical importance for obtaining efficient and stable organic light-emitting diodes(OLEDs). Here, we report some of our recent results on the development of new cathode interlayer materials for OLEDs. Some of our new materials show performance superior to that of LiF.

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