• Title/Summary/Keyword: ozone free

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Filler-Elastomer Interactions. 10. Ozone Treatment on Interfacial Adhesion of Carbon Blacks/NBR Compounds (충전재-탄성체 상호작용. 10. 카본블랙/NBR 복합재료의 계면 접착에 미치는 오존처리의 영향)

  • Cho, Ki-Sook;Zaborski, M.;Slusarski, L.;Park, Soo-Jin
    • Elastomers and Composites
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    • v.38 no.2
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    • pp.139-146
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    • 2003
  • In this work, the influence of ozone treatment on surface properties of carbon black is investigated in terms of X-ray photoelectron spectroscopy (XPS) and contact angles. And their mechanical interfacial properties of the carbon black/acrylonitrile butadiene rubber (NBR) compounds are studied by the crosslink density and composite tearing energy ($G_{IIIC}$). As a result, it is found that the increasing of the ozone concentration leads to an increase of the introduction rate of oxygen-containing functional groups onto carbon black surfaces and to an increase of the surface free energy, resulting in improving both crosslink density and tearing energy ($G_{IIIC}$) of the compounds. The results can be explained by the fact that the oxygen-containing functional groups of carbon black surfaces make an increase of the degree of adhesion at interfaces between carbon blacks and rubber matrix.

Ultraviolet-ozone irradiation of HPMC thin films: Structural and thermal properties

  • Abdel-Zaher, Nabawia A.;Moselhey, Manal T.H.;Guirguis, Osiris W.
    • Advances in materials Research
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    • v.6 no.1
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    • pp.1-12
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    • 2017
  • The aim of the work was to evaluate the effect of ultraviolet-ozone ($UV-O_3$) irradiation with different times on the structure and thermal properties of hydroxypropyl methylcellulose (HPMC) in the form of a thin film to be used as bioequivalent materials according to their important broad practical and medical applications. HPMC thin films were exposed to $UV-O_3$ radiation in air at a wavelength of 184.9 nm.The beneficial effects of this treatment on the crystallinity and amorphousity regions were followed by X-ray diffraction technique and FTIR spectroscopy. Differential scanning calorimetry, thermogravimetric and differntial thermal analyses were used in order to study the thermal properties of HPMC samples following the process of photodegradation. The obtained results indicated that the rate of degradation process was increased with increasing the exposure time. Variations in shape and area of the thermal peaks were observed which may be attributed to the different degrees of crystallinity after exposing the treated HPMC samples. This meant a change in the amorphousity of the treated samples, the oxidation of its chemical linkages on its surface and its bulk, and the formation of free radical species as well as bond formation.

Properties of Bleachability of Paper Mulberry Pulp by Hydrogen Peroxide and Ultrasonication Bleaching System (과산화수소와 초음파 표백 시스템에 따른 닥나무 펄프의 표백 효율 특성)

  • Seo, Jin-Ho;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.44 no.1
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    • pp.65-73
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    • 2012
  • Nowadays, the concern on the environmental load of bleaching process gave rise to the process of ECF(elemental chlorine free) and TCF(total clorine free). These sequences are based on oxygen-derived compounds such as oxygen, ozone, and hydrogen peroxide which is used as a typical eco-friendly bleaching agent. In this study, paper mulberry pulp was bleached with hydrogen peroxide and some bleaching process were accompanied with ultrasonication in order to increase the bleaching efficiency. The best bleaching efficiency of paper mulberry pulp was obtained in the condition of hydrogen peroxide and ultrasonication(20 kHz) bleaching system at $45^{\circ}C$ for 30 min. The brightness and kappa number of paper mulberry pulp were gained to 5.09% and 3.52 respectively. and yield was slightly loosed to 2%. Therefore, the efficiency of hydrogen peroxide and ultrasonication bleaching system of paper mulberry pulp was superior to the conventional hydrogen peroxide bleaching system. Magnesium sulfate acted as a bleaching stabilizer for the increasement of yield. As a result, the yield and viscosity were increased to 2.2% and 12% respectively.

Phase Stability of Bi2212 and Bi2223 Thin Films Fabricated by Ion Beam Sputtering

  • Lee, Hee-Kab;Park, Yong-Pil;Kim, Jeong-Ho
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2000.11a
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    • pp.108-111
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    • 2000
  • Bi2212 and Bi2223 thin films are fabricated by ion beam sputtering method. Three phases of Bi2201, Bi2212 and Bi2223 appear as stable ones in spite of the condition for thin film fabrication of Bi2212 and bi2223 compositions, depending on substrate temperature(T$\sub$sub/) and ozone pressure (PO$_3$). It is found out that these phases show similar T$\sub$sub/ and PO$_3$dependence, and that the stable regions of these phases are limited within very narrow temperature.

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Phase Stability Region of Bi-superconductor Thin Films Prepared by IBS Technique (이온빔 스퍼터법으로 제작한 Bi 초전도 박막의 상안정 영역)

  • Lim, Jung-Kwan;Chun, Min-Woo;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.308-311
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    • 2001
  • Bi-2212 and Bi-2223 thin films are prepared by IBS(ion beam sputtering) technique. Three phases of Bi-2201, Bi-2212 and Bi-2223 appear as stable ones in spite of the conditions for thin film fabrication of Bi-2212 and Bi-2223 compositions, depending on substrate temperature($T_{sub}$) and ozone pressure( $PO_3$ ). It is found out that these phases show similar $T_{sub}$ and $PO_3$ dependence, and that the stable regions of these phases are limited within very narrow temperature.

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A Study on the Formation of Single Crystal in BiSrCaCuO Thin Films (BiSrCaCuO 박막의 단결정 형성에 관한 연구)

  • Cheon, Min-Woo;Yang, Sung-Ho;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11b
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    • pp.39-42
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    • 2004
  • Bi-2212 and Bi-2223 thin films are prepared by IBS(ion beam sputtering) technique. Three phases of Bi-2201, Bi-2212 and Bi-2223 appear as stable ones in spite of the conditions for thin film fabrication of Bi-2212 and Bi-2223 compositions, depending on substrate temperature(Tsub) and ozone pressure(PO3). It is found out that these phases show similar Tsub and PO3 dependence, and that the stable regions of these phases are limited within very narrow temperature.

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A Study of De-electrification Characteristics of Charged Body By Soft X-Ray Ionizer (연X선 Ionizer에 의한 대전물체의 제전특성에 관한 연구)

  • 이동훈
    • Journal of the Korean Society of Safety
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    • v.13 no.3
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    • pp.67-73
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    • 1998
  • The technology for neutralizing static electricity by soft X-ray radiation has been newly developed. This technology involves ionization of gas molecules in the vicinity of a charged substrate to generate ions and electrons to reduce electrostatic potential. The ULSI device substrate and liquid crystal display substrate tend to get charged instantly to a high potential level when they are handled in the manufacturing process. Soft X-ray radiation is adequate in air or $O_2$ gas at atmospheric pressure. This newly developed neutralization method is effective to be superior to the conventional technique, i.e., an ionizer by using corona discharge ,in every aspect. The new method features excellent neutralization capability and is able to completely reduce electrostatic potential to 0 V within a short time. Moreover, this is a very clean antistatic technology free from particle generation ,ozone generation, and electromagnetic noise, which are problems in using the corona discharge ionizer.

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Phase Stability Region of Bi-superconductor Thin Films Prepared by IBS Technique (이온빔 스퍼터법으로 제작한 Bi 초전도 박막의 상안정 영역)

  • 임중관;천민우;박용필
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.308-311
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    • 2001
  • Bi-2212 and Bi-2223 thin films are prepared by IBS(ion beam sputtering) technique. Three phases of Bi-2201, Bi-2212 and Bi-2223 appear as stable ones in spite of the conditions for thin film fabrication of Bi-2212 and Bi-2223 compositions, depending on substrate temperature($T_{sub}$) and ozone pressure(PO$_3$). It is found out that these phases show similar $T_{sub}$ and PO$_3$ dependence, and that the stable regions of these phases are limited within very narrow temperature.

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Phase Stability of Bi2212 and Bi2223 Thin Films Fabricated by ion Beam Sputtering

  • Lee, Hee-Kab;Park, Yong-Pil;Kim, Jeong-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.11a
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    • pp.108-111
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    • 2000
  • Bi2212 and Bi2223 thin films are fabricated by ion beam sputtering method. Three phases of Bi2201, Bi2212 and Bi2223 appear as stable ones in spite of the condition for thin film fabrication of Bi2212 and bi2223 compositions, depending on substrate temperature(T$\sub$sub/) and ozone pressure (PO$_3$). It is found out that these phases show similar T$\sub$sub/ and PO$_3$ dependence, and that the stable regions of these phases are limited within very narrow temperature.

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Transformation of the enthalpy and the entropy in BSCCO:2212-2223 (BSCCO:2212-2223 박막의 엔탈피와 엔트로피 변화)

  • Cheon, Min-Woo;Park, No-Bong;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.589-590
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    • 2005
  • BSCCO:2212-2223 thin films were fabricated by using the ion beam sputter with a evaporation method at various substrate temperatures, $T_{sub}$, and ozone gas pressures, $pO_3$. The correlation diagrams of the BSCCO phases with Tsub and $pO_3$ are established in the 2212 and 2223 compositional films. In spite of 2212 compositional sputtering, Bi2201 and Bi2223 as well as Bi2212 phases come out as stable phases depending on Tsub and $pO_3$. From these results, the thermodynamic evaluation of ${\Delta}H$ and ${\Delta}S$, which are related with Gibbs' free energy change for single Bi2212 or Bi2223 phase, was performed.

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