• Title/Summary/Keyword: Functional Synthesis

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Synthesis of Trimetallic Au@Pb@Pt Core-shell Nanoparticles and their Electrocatalytic Activity toward Formic Acid and Methanol

  • Patra, Srikanta;Yang, Hae-Sik
    • Bulletin of the Korean Chemical Society
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    • v.30 no.7
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    • pp.1485-1488
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    • 2009
  • A facile, seed-mediated preparation method of trimetallic Au@Pb@Pt core-shell nanoparticles is developed. Au nanoparticles are the template seeds onto which sequentially reduced Pb and Pt are deposited. The trimetallic core-shell structure is confirmed by UV-Vis spectroscopy, TEM and EDS analysis, and cyclic voltammetry. The trimetallic Au@Pb@Pt core-shell nanoparticles show high electrocatalytic activity for formic acid and methanol electrooxidation.

Synthesis of CdS Nanocrystals with Different Shapes via a Colloidal Method

  • Bai, Jie;Liu, Changsong;Niu, Jinzhong;Wang, Hongzhe;Xu, Shasha;Shen, Huaibin;Li, Lin Song
    • Bulletin of the Korean Chemical Society
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    • v.35 no.2
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    • pp.397-400
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    • 2014
  • Size- and shape-controlled monodisperse wurtzite structured CdS nanorods have been successfully synthesized using a facile solution-based colloidal method. Depending on the control of injection/growth temperatures and the variation of Cd-to-S molar ratios, the morphology of the CdS nanocrystals (NCs) can be adjusted into bullet-like, rod-like, and dot-like shapes. X-ray diffraction (XRD), transition electron microscopy (TEM), and absorption spectroscopy were used to characterize the structure, morphology, and optical properties of as-synthesized CdS NCs. It was found that uniform CdS nanorods could be successfully synthesized when the injection and growth temperatures were very high (> $360^{\circ}C$). The aspect ratios of different shaped (bullet-like or rod-like) CdS NCs could be controlled by simply adjusting the molar ratios between Cd and S.

Synthesis and Optical properties of Functional Dye/MMA Copolymers (기능성 색소/MMA공중합체의 합성과 광학적 특성)

  • Lee, Bum-Hoon;Park, Jong-Ho;Yaung, Jae-Yun
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.214-217
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    • 2003
  • In recent years the focus of research in dye chemistry has largely changed from involvement in the traditional chemistry of dyes and pigments to investigations of functional dyes. With the development of the elcetronics and information industries, the importance of functional dyes has increased. Many research papers have been published concerning new synthetic methods and mechanicsm of functional dyes. Highly functionalized dicyanopyrazine derivatives can be used as fluorescent dyestuffs, emitters for electroluminescent devices tec. (omitted)

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Synthesis and Characterization of Acrylic Polymer Containing Silk Protein

  • Zhongmin Chen;Kim, Mutsumi ura;Masahiro Suzuki;Yoshiyuki Kondo;Kenji Hanabusa;Hirofusa Shirai
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.87-87
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    • 2003
  • Three kinds of acrylic polymers containing silk protein were synthesized, which are (1) blending of silk fibroin (SF) fiber and polyacrylonitrile (PAN); (2) graft-copolymer of PAN onto SFs; (3) random-copolymer synthesized by copolymerization of acrylonitrile (AN) and silk fibroin peptide (SFP) with vinyl groups, and their solubility, thermal property, and moisture absorption was investigated, respectively. These polymers have difference solubility and attributable to their structure. Their excellent thermal stabilities and better moisture absorptions were indicated.

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Synthesis of Epoxy Functional Siloxane and its Effect on Thermal Stress

  • Hyun, Dae-Sup;Jeong, Noh-Hee
    • Journal of the Korean Applied Science and Technology
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    • v.26 no.4
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    • pp.379-384
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    • 2009
  • Epoxy resin based encapsulants are widely used in semiconductor packaging applications. Epoxy resin based encapsulants are often subject to crack or delamination during the reliability test due to the thermal stress caused by high modulus nature of epoxy resins. Epoxy functional siloxanes are often added into epoxy resin to reduce the modulus so that the thermal stress can be reduced. Epoxy functional siloxanes, additives for reduced modulus, were synthesized and added into the curable epoxy resins. The modulus and the coefficient of thermal expansion (CTE) were also measured to investigate the thermal stress and to see whether the epoxy functional siloxane adversely affects the CTE or not. As a result, around 26% to 72% of thermal stress reduction was observed with no adverse effect on CTE.

Synthesis and Mesomorphic Properties of Achiral Liquid Crystals with 1,3-Dialkoxy-2-propyl Swallow-Tail

  • Lee, Seng-Kue;Bang, Mi-Yeon;Lee, Jong-Gun;Kang, Kyung-Tae;Kim, Yong-Bae
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.575-577
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    • 2003
  • Achiral swallow-tailed liquid crystals derived from 1,3-dialkoxy-2-propanol were prepared and their mesomorphic properties were investigated. 1,3-Dialkoxy-2-propyl swallow-tailed material showed antiferroelectric-like smectic C phase at lower temperature and in broader temperature range than the corresponding compounds with a branched alkyl group as a swallow-tail. They could serve as suitable host for antiferroelectric mixtures.

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Activity-dependent plasticity in skeletal muscle (골격근의 활동 의존적 가소성)

  • Kim, Sik-Hyun
    • PNF and Movement
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    • v.6 no.1
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    • pp.41-51
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    • 2008
  • Purpose : This paper reviews evidence supporting adaptive plasticity in skeletal muscle fibers induced by various exercise training and neuromuscular activity. Result : Skeletal muscle fiber demonstrates a remarkable adaptability and can adjust its physiologic and contractile makeup in response to alterations in functional demands. This adaptive plasticity results from the ability of muscle fibers to adjust their molecular, functional, and contractile properties in response to altered physiological demands, such as changes in exercise patterns and mechanical loading. The process of activity-dependent plasticity in skeletal muscle involves a multitude of signalling mechanisms initiating replication of specific genetic sequences, enabling subsequent translation of the genetic message and ultimately generating a series of myosin heavy chain isoform. Conclusions : Knowledge of the mechanisms and interaction of activity-dependent adaptive pathways in skeletal muscle is important for our understanding of the synthesis of muscle myosin protein, maintenance of metabolic and functional capacity with physical activity, and therapeutic intervention for functional improvement.

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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
    • Korean Journal of Metals and Materials
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    • v.48 no.9
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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.