• Title/Summary/Keyword: Fluorination

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Preparation and Electrochemical Characterization of Activated Carbon Electrode by Amino-fluorination (아미노불소화 반응에 의한 활성탄소전극 제조 및 전기화학적 특성)

  • Lim, Jae Won;Jeong, Euigyung;Jung, Min Jung;Lee, Sang Ick;Lee, Young-Seak
    • Applied Chemistry for Engineering
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    • v.22 no.4
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    • pp.405-410
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    • 2011
  • High-performance of an electric double layer capacitance (EDLC) electrode was prepared by the amino-fluorination of activated carbon by using $NF_3$ gas. The pore structure and surface chemistry were investigated based on the specific capacitance of EDLC. The amino-fluorination of activated carbon introduced functional groups of nitrogen and fluorine which are beneficial for the specific capacitance of EDLC without the change of pore structures. The E-NF100AC electrode, which has nitrogen and fluorine functional groups less than 1 at%, showed the highly improved specific capacitance of 528 (${\pm}9$) F/g at 2 mV/s showing 122% improved value when comparing with that of non-functionalized E-RAC electrodes. Whereas, the E-NF200AC electrode, which has nitrogen and fluorine functional groups over 1 at%, showed the decreased specific capacitance because of perfluorinated introduction. So, it is concluded that the proper contents of nitrogen and fluorine groups improved the specific capacitance of EDLC.

Influence of Plasma Treatment on The Soil Release Properties of Polyester Fabrics (플라즈마처리가 폴리에스테르 직물의 오염제거성에 미치는 연구)

  • Kwon, Young-Ah
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.434-435
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    • 2003
  • Physicochemical properties of a polymer surface significantly affect adhesion, wetting, and dyeing properties. In recent years, low temperature plasma technology has been widely used for surface modification of polymers. Surface fluorination by low temperature plasma treatment has been employed to improve the water and oily repellency of textile fabrics. However, very few results have been reported on soil release properties of the oxygen plasma treated textile fabrics. (omitted)

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Superconductivity in Fluorinated $YBa_2Cu_3O_{6+x}$

  • Lee, Cheol-Eui;D, White;P.K, Davies
    • Journal of Magnetics
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    • v.1 no.2
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    • pp.57-59
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    • 1996
  • The YBa$_2$Cu$_3$O6+xstructures have been fluorinated by a gas phase exchange technique, and 19F NMR was used to identify the structural fluorine. Magnetic susceptibility measurements showed that the fluorination turned a marginally nonsuperconducting sample into a 40 K superconductor, as well as that it raised the onset of the superconducting transition of the 60 K superconductor YBa$_2$Cu$_3$O6.7 to about 100 K.

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Recent Liquid Crystal Material Development for VA-TFT

  • Bremer, Matthias
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1067-1070
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    • 2005
  • A large size flat panel LCD-TV must fulfill different requirements than a desktop LCD-monitor: The contrast must be much larger, the viewing angle should be as wide as possible and the switching times must be shorter to allow moving pictures to be displayed naturally. The "Vertically Aligned" technology is most promising to realize such a product. LC-material development for this technology began at Merck about 10 years ago. New materials based on the 1,1,6,7-tetrafluoroindane skeleton were recently synthesized via ortho-metallation and intramolecular Heck cyclization followed by an oxidative fluorination procedure. The materials offer improved properties over liquid crystals currently employed in flat panel LCD-TVs.

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Electro-optic Properties of Reflective HPDLC with Fluorinated Polymer Matrices

  • Woo, Ju-Yeon;Kim, Eun-Hee;Kim, Byung-Kyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.516-519
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    • 2003
  • We modified the molecular structure of urethane acrylate oligomer by varying raw materials. Also fluorination of the host polymer matrices has been found to influence the morphological and the electrooptical properties of the resulting HPDLC grating. The incorporation of fluorinated monomers in HPDLC formulation enhance the LC phase separation and improved elctro-optical properties.

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Adsorption Characteristics of Toluene Gas Using Fluorinated Phenol-based Activated Carbons (불소화 처리된 페놀계 활성탄소를 이용한 톨루엔 가스흡착 특성)

  • Kim, Min-Ji;Jung, Min-Jung;Kim, Min Il;Choi, Suk Soon;Lee, Young-Seak
    • Applied Chemistry for Engineering
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    • v.26 no.5
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    • pp.587-592
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    • 2015
  • Activated carbons (ACs) were treated by fluorination to improve the adsorption property of toluene gas among volatile organic compounds (VOCs). The pore characteristics and surface properties of these activated carbons were evaluated by BET and XPS and the adsorption property and removal efficiency of toluene gas was investigated by gas chromatography. The breakthrough time of fluorinated ACs was increased about 27% compared to that of untreated ACs when the toluene gas of 100 ppm was flowed at a flow rate of $300cm^3/min$. Fluorinated AC of 0.1 g adsorbent totally adsorbed toluene gas in 100 ppm to 100 % during the adsorption time in 19 h. These results can be used as a treatment technology or removal of carcinogenic materials such as toluene.