• Title/Summary/Keyword: ZnO 나노입자

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The Study on Thermal Analysis and Thermodynamic Characteristics of Spinel Compounds(ZnCo2O4, NiCo2O4) (스피넬 구조를 가지는 전이금속화합물(ZnCo2O4, NiCo2O4)의 열적 분석 및 열역학적 특성 연구)

  • Kim, Jae-Uk;Ji, Myoung-Jin;Cha, Byung-Kwan;Kim, Chul-Hyun;Jang, Won-Cheoul;Kim, Jong-Gyu
    • Journal of the Korean Chemical Society
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    • v.54 no.2
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    • pp.192-197
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    • 2010
  • The spinel compound was obtained by the thermal decomposition of Zn-Co and Zn-Ni gel prepared by sol-gel method using oxalic acid as a chelating agent. The formation of spinel compound has been comfirmed by thermogravimetric analysis (TGA), x-ray powder diffraction (XRD) and infrared spectroscopy (IR). The particle size of 13 nm~16 nm was calculated by Scherrer's equation. The sol-gel method provides a practicable and effective route for the synthesis of the spinel compound at low temperature ($350^{\circ}C$). The kinetic parameters such as activation energy (Ea) and pre-exponential factor (A) for each compound were found by means of the Kissinger method and Arrhenius equation. The decomposition of spinel compound has an activation energy about 155 kJ/mol. Finally, the thermodynamic parameters (${\Delta}G^{\varphi}$, ${\Delta}H^{\varphi}$, ${\Delta}S^{\varphi}$) for decomposition of spinel compound was determined.

Recent Research Trends in Antibacterial, Antifungal, and Antiviral Active Packaging (항균, 항진균 및 항바이러스 액티브 패키징의 최근 연구 동향)

  • Siyeon Park;Hani Ji;Jieun Choi;Seulgi Imm;Yoonjee Chang
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.29 no.1
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    • pp.15-25
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    • 2023
  • Since the COVID-19 crisis, the use of disposable packaging materials and delivery services, which raise environmental and social issues with waste disposal, has significantly increased. Antimicrobial active packaging has emerged as a viable solution for extending the shelf-life of foods by minimizing microbial growth and decomposition. In this review article, we provide a comprehensive overview of current research trends in antimicrobial active film and coating published over the last five years. First, we introduced various polymer materials such as film and coating that are used in active packaging. Next, various types of antimicrobial (antibacterial, antifungal, and antiviral) packaging including essential oil, extracts, biological material, metal, and nanoparticles were introduced and their activities and mechanisms were discussed. Finally, the current challenges and prospects were discussed. Overall, this review provides insights into the recent advancements in antimicrobial active packaging research and highlights the potential of the technology to enhance food safety and quality.

Synthesis and Characterization of Mica Coated with Zinc Oxide Nanoparticles (산화 아연 나노 입자로 도포된 마이카의 합성 및 특성 규명)

  • Kil, Hyun Suk;Kim, Young Ho;Park, Minyoung;Rhee, Seog Woo
    • Applied Chemistry for Engineering
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    • v.23 no.3
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    • pp.271-278
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    • 2012
  • In this work, we have prepared the nanocomposite by the reaction of mica and zinc oxide, and investigated the application of nanocomposite to UV protecting creams. Mica treated with 3-aminopropyltrimethoxysilane (APTMS) reacted with 1,4-phenylenediisothiocyanate (PDC) to give -N=C=S functionalized surface, which was further reacted with zinc oxides coated with APTMS to give mica-zinc oxide nanocomposites. The composites were characterized by EA, EDS, TGA, SEM, zeta potential measurement, powder XRD, and DRS UV/Vis analyses. Finally, we measured transmittances of ultraviolet protection creams manufactured by using mica composite covered with zinc oxides in the range of 280~400 nm. The nanocomposites developed in this work might be applicable as inorganic hybrid materials for UV protecting creams.