• 제목/요약/키워드: Dispersion Property

검색결과 338건 처리시간 0.026초

Image Analysis of Surimi Sol and Gel in Composite System

  • Yoo, Byoung-Seung;Lee, Chong M.
    • Preventive Nutrition and Food Science
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    • 제3권3호
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    • pp.292-294
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    • 1998
  • Surimi sol and gel were prepared by mixing egg albumin, starch, oil and carrageenan, which are used as representative ingredients in the surimi composite, at different ratio. Structural properties in surimi composite were investigated by examining the phase changes and dispersion pattern (average particle size, size range and the averge number of particle) of the particulate ingredients in sol and gel with an image analyzer. A staining technique of the specimen containing egg albumin in surimi gel was developed by adjusting pH of a toluidine staining solution. Image analysis revealed that size and density of ingredient particles were function of the level and dispersion of ingredients except of starch-incorporated surimi gel which showed maximum particle size at 6%.

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Preparation and Characterization of Polyimide/Carbon-Nanotube Composites

  • Kim, Bong-Sup;Bae, Sang-Hoon;Park, Young-Hwan;Kim, Ji-Heung
    • Macromolecular Research
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    • 제15권4호
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    • pp.357-362
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    • 2007
  • Polyimide/carbon nanotube (CNT) composite films, for potential use in high performance microelectronics and aerospace applications, were prepared by mixing a polyisoimide (PII) solution and a CNT suspension in NMP, followed by casting, evaporation and thermal imidization. The CNTs were modified by a nitric acid treatment to improve the thermal and electrical properties, as well as to provide good dispersion of the CNTs in a polymer matrix. The formation of functional groups on the modified CNT was confirmed by Raman spectroscopy. Scanning electron microscopy revealed the modified CNTs to be well dispersed in the polyimide matrix, with a uniform diameter of ca. 50 nm. The thermal stability of the films containing the CNTs was improved due to the enhanced interfacial interaction and good dispersion between the polyimide matrix and modified CNTs. In addition, the thermal expansion coefficient of the composites films was slightly decreased, but the dielectric constants increased linearly with increasing CNT content.

Stabilization and Thermal Properties of Carbon Nanotubes/Cu Nanocomposites Prepared by Molecular-Level Mixing

  • Hong, Youn-Jeong;Jung, Chung-Hun;Kim, Hye-Jin;Lee, Kyu-Mann
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.1378-1381
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    • 2006
  • The CNTs are the most extensively studied material which are characterized by the complete property of matter, structure, and the large thermal conductivity (Thermal conductivity of $CNTs\;{\sim}>2000W/mK$ vs. Thermal conductivity of Aluminum ${\sim}\;>204W/mK$). Thus, they are successfully applied to the various fields. However, due to the strong agglomeration caused by the van der waal's force, their applications are limited. In the present study, a new method for CNTs dispersion was developed by using the mechanical dispersion, acid treatment, and then Cu was coated. This process produces CNTs/Cu nanocomposite powders, whereby the CNTs are homogeneously located within the Cu powders. The thermal properties of the CNTs/Cu nanocomposite were investigated.

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전기장분산법을 이용한 나노와 마이크로 혼합된 콤포지트의 전기적 특성 (Electrical Properties for Micro-and-Nano- Mixture Composites using Electric Field Dispersion)

  • 김정호;조대령;박재준
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 춘계학술대회 논문집
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    • pp.32-32
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    • 2010
  • A epoxy/multilayered silicate nanocomposite was prepared by a new AC electric application method and micro silica particle was poured into the nanocomposite in order to prepare epoxy/micro-and-nano- mixed composites (EMNC). Electric insulation breakdown strength was measured in a sphere-sphere electrode system designed for the prevention of edge breakdown and the data were estimated by Weibull plot. As the exfoliated silicate nano-plates were homogeniously dispersed in the micro silica particles, the insulation property was higherd.

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Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/Graphene Oxide Nanocomposite Films: Thermomechanical Properties, Oxygen Transmission Rates, and Hydrolytic Degradation

  • You, Eun Jung;Ha, Chang-Sik;Kim, Gue-Hyun;Lee, Won-Ki
    • 한국환경과학회지
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    • 제26권1호
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    • pp.1-10
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    • 2017
  • In this study, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/graphene oxide (GO) nanocomposite films containing various content of GO were prepared using solution casting method. The effect of GO content on Young's modulus and dispersion of GO in PHBV matrix was investigated. Also, the thermomechanical properties, oxygen transmission rates and hydrolytic degradation of PHBV/GO nanocomposite films were studied. The addition of GO into PHBV improves the Young's modulus and decreases thermal expansion coefficient. The improvement can be mainly attributed to good dispersion of GO and interfacial interactions between PHBV and GO. Furthermore, PHBV/GO nanocomposite films show good oxygen barrier properties. PHBV/GO nanocomposites show lower hydrolytic degradation rates with increasing content of GO.

극초경량 실리카 에어로겔의 폴리우레탄 멤브레인 적용 특성 (Application Properties of Ultra Light Weight Silica Aerogel to Polyurethane Membrane)

  • 민문홍;정천희;윤석한;양정한;김태경
    • 한국염색가공학회지
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    • 제25권4호
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    • pp.279-286
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    • 2013
  • Application properties of ultra light weight silica aerogel toward polyurethane membranes were investigated. From the results of pre-milling process of the silica aerogel, the solvent for dispersion of the aerogel was determined for methyl ethyl ketone and its content in the solvent was determined by 30%. Using this aerogel dispersion, the polyurethane membranes were prepared according to the mixing amount of silica aerogel and various properties of the membranes were investigated. As results, the optimum mixing amount of silica aerogel inside polyurethane membranes was decided at 11%, because the improvement of light weight property, air permeability, and moisture vapor permeability were improved upto 11% of silica aerogel content, maintaining the water penetration resistance almost unchanged.

이방성 복합재료 판에서의 램파 방정식 (The Lamb Wave Equation in a Composite Plate with Anisotropy)

  • 이상호
    • 한국군사과학기술학회지
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    • 제13권1호
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    • pp.126-132
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    • 2010
  • A Lamb wave guided by a plate structure has dispersive characteristics because phase and group velocity change with the variation of frequency and thickness. The Lamb wave has two modes, symmetric and anti-symmetric mode, which propagates symmetrically and non-symmetrically with respect to centerline. In this paper, the derivation of Lamb wave equation with anisotropic material property is investigated. The phase velocity and group velocity dispersion curves are shown using the stiffness matrix of composite materials with the variation of angle.

Preparation of Carbon Composite with High Oxidation Resistance by MoSi2 Dispersion

  • Goto, S.;Kodera, M.;Toda, S.;Fujimori, H.;Ioku, K.
    • The Korean Journal of Ceramics
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    • 제5권2호
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    • pp.115-118
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    • 1999
  • Carbon composites with $MoSi_2$ dispersion were prepared by hot-pressing at $1700^{\circ}C$ under 30 MPa for 1 h using polysilazance as binding material. The composites consisted of C, $Mo_{4.8}Si_3C_{0.6}$ and SiC. Bulk density and porosity of the carbon composites with 10 vol% $MoSi_2$ was 1.8g.$\textrm{cm}^{-3}$ and 34%, respectively. This composite was oxidized about 0.05mm from the surface of the carbon composite after oxidation test at $1500^{\circ}C$ for 10h in air. Formation of the $SiO_2$ glass layer was observed by SEM. When this composite suffered damage in the coating layer, it had hardly farther oxidation because of its self-repairing property. The composite prepared in this study indicated good oxidation resistance.

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식각된 열확산 코어 광섬유를 이용한 고감도 온도 센서 (Highly sensitive temperature sensor based on etched fiber with thermally expanded core)

  • 김광택;송현석;신은수;홍기범
    • 센서학회지
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    • 제15권4호
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    • pp.263-268
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    • 2006
  • We have demonstrated a highly sensitive temperature sensor using an etched single mode fiber with a thermally expanded core region. Large core size of thermally expanded core facilitates access to evanescent wave by the wet etching. The etched region was surrounded by a low dispersive external medium with high thermo-optic coefficient. Due to the large difference between the dispersion property of the fiber and that of the external medium, the device reveals a cut-off properties at spectral region. The cut-off wavelength was shifted by the variations of the environmental temperatures because of thermo-optic effect of the external medium. The sensitivity of the fabricated device was found to be $45nm/^{\circ}C$.

백색광 간섭계를 이용한 광학소자의 군지연분산 측정 (Measurement of the group-delay dispersion of optical elements using white-light interferometry)

  • Tayyab Imran;Hong, Kyung-Han;Yu, Tae-Jun;Nam, Chang-Hee
    • 한국광학회:학술대회논문집
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    • 한국광학회 2003년도 하계학술발표회
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    • pp.248-249
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    • 2003
  • The characterization of laser mirrors is important for obtaining proper performance of femtosecond lasers. Characteristics of laser mirrors are usually described in terms of their reflectivity at a certain wavelength. In femtosecond laser applications, however, the dispersion property of the mirror should be considered because the temporal shape of a femtosecond light pulse changes during the reflection at the mirrors. (omitted)

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