• Title/Summary/Keyword: Adhesion Evaluation

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Recent Advances in Scanning Acoustic Microscopy for Adhesion Evaluation of Thin Films

  • Ju, Hyeong-Sick;Tittmann, Bernhard R.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.29 no.6
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    • pp.534-549
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    • 2009
  • As the thin film technology has emerged in various fields, adhesion of the film interface becomes an important issue in terms of the longevity and durability of thin film devices. Diverse nondestructive methods utilizing acoustic techniques have been developed to assess the interfacial integrity. As an effective technique based on the ultrasonic wave focusing and the surface acoustic wave(SAW) generation, scanning acoustic microscopy(SAM) has been investigated for adhesion evaluation. Visualization of film microstructures and quantification of adhesion weakness levels by SAW dispersion are the recent achievements of SAM. To overcome the limitations in the theoretical dispersion model only suitable for perfectly elastic and isotropic materials, a new model has been more recently developed in consideration of film anisotropy and viscoelasticity and applied to the adhesion evaluation of polymeric films fabricated on semiconductive wafers.

Adhesion Strength Measurement of Rabbit Knee Chondrocyte (연골세포 부착력 평가)

  • Lee Kwon-Yong;Park Sang-Guk;Shin Daehwan;Park Jong-Chul
    • Tribology and Lubricants
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    • v.21 no.5
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    • pp.236-240
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    • 2005
  • In order to prepare for the suitable surfaces of implants or medical devices, quantitative evaluation of adhesion between cells and biomaterials is essential. To better understand adhesion formation between cells and biomaterials, we used the cytodetachment technique which measures the adhesive force of a single cell through changing the, culture time and detachment speed. The results showed that the adhesive force could be affected by the culture time of cells on the surface of materials and the detachment speed. Moreover, there was a large discrepancy among the adhesion strength measured by similar techniques conducted on the different cells and substrates. It can be 'concluded that the variation of the force measurement technique can seriously alter the level of the force required to detach a cell on the surface of materials.

Evaluation of Adhesion Performance of Stones Bonded with Epoxy according to Environmental Conditions (환경조건에 따른 에폭시로 접착된 석재의 부착성능평가)

  • Kim, Young-Min;Im, Geon-Woo;Lim, Chang-Min;Lee, Gun-Cheol;Oh, sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.11a
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    • pp.39-40
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    • 2023
  • Recently, due to the advancement of buildings, finishing methods using stone are increasing. However, finishing methods are not standardized and rely on workers' arbitrary methods. In stone finishing, many building defects occur due to adhesion performance, so the adhesion performance of stones attached with epoxy is important. Therefore, in this study, the adhesion performance of stones attached with epoxy was evaluated by exposing them to various environments. As a result of the experiment, the test specimens exposed to thermal shock showed only 20% of the standard test specimens' adhesion performance, and the test specimens cured at high and low temperatures showed the standard test specimens. It was expressed in 65-80% of the test specimens. Therefore, the adhesion performance of stone using epoxy was found to be vulnerable to repeated harsh environments.

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Cell-cell Adhesion of Jurkat T Cells Induced by CD29 and CD98 Activation and its Application (CD29 및 CD98 활성 매개에 의한 Jurkat T 세포의 유착과 그 활용)

  • Kim, Byung-Hun;Cho, Jae-Youl
    • YAKHAK HOEJI
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    • v.53 no.3
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    • pp.119-124
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    • 2009
  • Cell-cell adhesion managed by various adhesion molecules plays an important role in regulating functional activation of cells. This event mediates attachment of inflammatory cells to endothelial cells, interaction of antigen-presenting cells with T cells and metastatic adherence of cancer cells to epithelial tissue cells. Therefore, this cellular response is considered as one of therapeutic target to treat various cancers and inflammatory diseases. To develop proper model for evaluation of functional activation of adhesion molecules, the ability of U937 and Jurkat T cells responsive to various adhesion inducers such as phorbal-12-myristate-13-acetate (PMA), staurosporin and monoclonal antibodies to CD29, CD43 and CD98 was investigated using quantitative cell-cell adhesion assay. U937 cells made more cell-cell clusters by the treatment of antibodies to CD29 and CD43 than Jurkat T cells, while Jurkat T cells exhibited increased cell-cell adhesion ability in CD98 antibody treatment. In agreement, the surface levels of CD29 and CD98 were highly observed in U937 and Jurkat T cells, respectively. Therefore, our data suggest that Jurkat T and U937 cells can be used for model system to evaluate functional activation of adhesion molecules such as CD29 and CD98.

Comparison between Shear and Tensile Adhesion Strength of Cement for Ceramic Tiles and an Experimental Evaluation on the Cutting Effect of Tile for Tensile Adhesion Strength (타일 시멘트 전단접착강도와 인장부착강도 비교 및 인발부착강도 타일커팅 영향에 관한 실험적 평가)

  • Lee, Sang-Hyun;Ki, Jun-Do;Cho, Hong-Bum;Kim, Young-Sun;Moon, Hyung-Jae;Jeon, Hyun-Su
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.181-182
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    • 2021
  • Selecting a proper tile cement for ceramic tile is important to secure tile construction quality. But there is some ambiguity in standards about evaluating adhesion test such as using KS L 1593 in Lab test but using KS L 1592 in site. So, this study aims to how to select proper tile cement for securing adhesion strength in site considering both tensile and shear adhesion strength of cement for ceramic tile. Also, when doing tensile adhesion test in site, there may be adhesion drop because of cutting tile with grinder. As a result, drop of adhesion strength is about 9% ans quality manager consider these factor and should select proper tile cement.

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Evaluation of the Adhesion Strength of Metal Spray Coating System in Steel using High-frequency Arc Metal Spray Method (고주파 아크 금속용사기를 이용한 금속용사 코팅계의 부착강도 평가)

  • Choe, Hong-Bok;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.96-97
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    • 2014
  • The purpose of this study is to analyze the adhesion strength of metal spray coating system in steel using high-frequency arc metal spray method. For the purpose the experimental factor such as surface roughness was selected at 3 levels. As a result of experiment, it appeared that high-frequency arc metal spray method had higher adhesion strength than existing metal spray method. Especially, Al-Mg showed the highest adhesion strength than other metals. In case of surface roughness, the higher roughness steel has, the higher adhesion strength appeared.

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Historical Trends of Micromechanical Testing Methods for Structural Fiber Reinforced Composites to Evaluate the Interfacial Adhesion (구조용 섬유강화복합재료의 계면접착 특성 평가를 위한 미세역학시험법의 연구동향 고찰)

  • Park, Joung-Man;Kim, Jong-Hyun;Kim, Dong-Uk;Kwon, Dong-Jun
    • Journal of Adhesion and Interface
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    • v.23 no.3
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    • pp.59-69
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    • 2022
  • In composite materials, the adhesion and interfacial properties were the most important factors to obtain high performance of mechanical properties. This review paper had been focused on the micromechanical evaluation methods for the interfacial property historically. The interfacial property of fiber-reinforced composites (FRC) could be evaluated using only a single fiber and matrix via various micromechanical testing methods. Self-sensing due to the fracture behavior of FRC could be determined and discussed more critically and clearly using electro-micromechanical evaluation. In this paper, the research trends for micro-mechanical evaluation of composites was summarized, and their practical applications would be suggested in the future.

Adhesion Strength Measurement of Chondrocyte (연골세포 부착력 평가)

  • Lee K. Y.;Park S. K.;Shin Deahwan;Park J. C.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2004.11a
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    • pp.362-366
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    • 2004
  • Quantitative evaluation of substrates for cells is essential to understanding cell-material adhesive interaction and it is also necessary for the development of new biomaterials. Many cells on adhesive molecules will form an organization of actin into bundles and production of the large, highly organized structures termed focal adhesions. To better understand adhesion formations between cells and substrata, we have quantified the force required to displace attached cell. we allowed rabbit knee chondrocyte to attach on a substratum of microscope slide glass. Our results demonstrate that a force is required to detach cells is changed according to detachment time variation.

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