• Elastomers and Composites
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• v.36 no.3
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• pp.195-200
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• 2001

Ultraviolet photografting of acrylic acid onto low density polyethylene was characterized using XPS and contact angle measurement. Effects of surface modification at LDPE and aluminum on LDPE/Al laminate were also investigated. Contact angle decreased significantly at initial state arid tends to level off with increasing UV irradiation time. The improvement of hydrophilicity was due to the presence of acrylic acid on LDPE surface. Graft of acrylic acid onto LDPE was also identified from O1s/C1s ratios in XPS spectrum. Adhesion strength of LDPE-g-AAc/Al laminate showed about 30 times higher than LDPE/A1 system and it could be attributed to the increase of polarity of LDPE surface. Chemical treatment of Al surface using sulfuric acid/sodium dichromate also increased the adhesion strength of LDPE/Al laminate. Adhesion strength of LDPE/Al laminate decreased significantly under acetic acid.

• YAKHAK HOEJI
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• v.51 no.6
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• pp.482-489
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• 2007

Kaempferitrin, isolated from Kenaf (Hibiscus cannabinus), was examined to evaluate its modulatory effects on antigen-presenting cell functions of macrophages/monocytes such as phagocytosis of foreign materials, up-regulation of costimulatory molecules (CD40, CD80 and CD86), adhesion molecule activation, and antigen processing and presentation. Kaempferitrin strongly blocked up-regulation of CD40, CD80 and CD86, but not pattern recognition receptor (PRR) (e.g., TLR2). It also suppressed functional activation of CD29 (${\beta}1$-integrins), as assessed by cell-cell adhesion assay, required for T cell-antigen-presenting cell (APC) interaction. Furthermore, this compound did not block a simple activation of CD29, as assessed by cell-fibronectin adhesion assay. However, the compound did not diminish phagocytic uptake, an initial step for antigen processing, and ROS generation in RAW264.7 cells. In particular, to understand molecular mechanism of kaempferitrin-mediated inhibition, the regulatory role of LPS-induced signaling events was examined using immunoblotting analysis. Interestingly, this compound dose dependently suppressed the phosphorylation of $I{\kappa}B{\alpha}$, Src, Akt and Syk, demonstrating that it can negatively modulate the activation of these signaling enzymes. Therefore, our data suggested that kaempferitrin may be involved in regulating APC function-relevant immune responses of macrophages and monocytes by regulating intracellular signaling.

• Applied Chemistry for Engineering
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• v.3 no.3
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• pp.422-429
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• 1992

The morphology and adhesion properties of rubber compounds containing resorcinol formaldehyde(RF) resin and hexamethoxymethylmelamine(HMMM) used in adhesion of rubber to brass-plated steel cord was investigated. The resins were spherical particles about $2000{\AA}$ diameter and distributed in rubber compounds homogeneously, and the cured compound with steel cord showed migration of resin to steel cord. Also, modulus was increased with increasing HMMM contents. The loss of adhesion between rubber and steel cord was likely to be at initial stages by thermal aging. Considering the physical properties, suability of adhesion layer and thermal aging property, optimum ratio of RF resin and HMMM was 1 : 0.9.

• Journal of the Korean institute of surface engineering
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• v.32 no.4
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• pp.496-502
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• 1999

Electroplating of Ag and Au on the functional area of lead frames are required for good bonding ability in IC packaging. As the patterns of the lead frame become finer, development of new deposition technology has been required for solving problems associated with process control for uniform thickness on selected area. Sputtering was employed to investigate the adhesion between substrate Alloy42 and Ag film as a new candidate process alternative to conventional electroplating. Coating thickness of Ag film was controlled to 3.5$\mu\textrm{m}$ at room temperature as a reference. The deposition of film was optimized to ensure the adhesion by process parameters of substrate heating temperature at $100~300^{\circ}C$, sputter etching time at -300V for 10~30min, bias voltage of -100~-500V, and existence of Cr interlayer film of $500\AA$. The critical $load L_{c}$ /, defined as the minimum load at which initial damage occurs, was the highest up to 29N at bias voltage of -500V by scratch test. AFM surface image and AES depth profile were investigated to analyze the interface. The effect of bias voltage in sputtering was to improve the surface roughness and remove the oxide on Alloy42.

• Journal of Adhesion and Interface
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• v.13 no.2
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• pp.89-93
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• 2012

In this study, the properties of acryl emulsion with adjunction procedures of tackifier resin and tackifier emulsion were investigated. Glass transition temperature of acryl emulsions was increased with the content of tackifiers. The initial strength showed the maximum value when the contents of tackifier resin and tackifier emulsion were 10 phr and 15 phr, respectively. Additionally, the strengths on heat and water resistances were increased with the contents of tackifier.

• Environmental Engineering Research
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• v.13 no.3
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• pp.136-140
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• 2008

$TiO_2$ photocatalyst has been known to exhibit a notable disinfecting activity against a broad spectrum of microorganisms. A lot of commercial $TiO_2$ photocatalyst products have been developed for antimicrobial purposes. However, a standard method has not yet been proposed for use in testing antimicrobial activity. In this study, we developed a $TiO_2$ photocatalytic adhesion test method with film as the standard testing method for the evaluation of antimicrobial activity. This method was devised by modifying the previous antimicrobial products test method, which has been widely used, and considering the characteristics of $TiO_2$ photocatalytic reaction. The apparatus for testing the antimicrobial activity was composed of a Black Light Blue (BLB) lamp as UV-A light source, a Petri dish as the cover material, and a polypropylene film as the adhesion film. The standard $TiO_2$ photocatalyst sample, Degussa P25 $TiO_2$ - coated glass, could only be used once. The optimal initial concentration of the microorganism, proper light intensity, and light irradiation time were determined to be $10^6$ CFU/mL, 1.0 mW/$cm^2$, and 3 hr, respectively, for testing and evaluating antimicrobial activity on the $TiO_2$ surface.

• Journal of Adhesion and Interface
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• v.18 no.4
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• pp.166-170
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• 2017

In this study, acrylic rubber pressure sensitive adhesives was polymerized with 2-ethylhexyl acrylate, styrene, butadiene, 2-hydroxyethyl acrylate, and acrylic acid by controlling the initiator content. The initial tackiness, peel strength, holding power, and heat resistance of the PSAs were investigated by changing the content of tackifier and curing agent. The results showed that the initial tackiness and peel strength increased as the content of tackifier increased, whereas the holding power decreased. Also, the results exhibited that that the initial tackiness, peel strength, and heat resistance decreased as the content of curing agent increased, whereas the holding power and decreased.

• The Journal of Advanced Prosthodontics
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• v.11 no.1
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• pp.41-47
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• 2019

PURPOSE. Surface finishing of a zirconia restoration is essential after clinical adjustment. Herein, we investigated the effects of a surface finishing protocol for monolithic zirconia on final roughness and bacterial adherence. MATERIALS AND METHODS. Forty-eight disk-shaped monolithic zirconia specimens were fabricated and divided into four groups (n = 12) based on initial surface treatment, finishing, and polishing protocols: diamond bur+polishing bur (DP group), diamond bur+stone grinding bur+polishing bur (DSP group), no diamond bur+polishing bur (NP group), and no diamond bur+stone grinding bur+polishing bur (NSP group). Initial and final surface roughness was measured with a profilometer, and shown using scanning electron microscope. Bacterial adhesion was evaluated by quantifying Streptococcus mutans in the biofilm. Kruskal-Wallis and Mann-Whitney U tests were used to compare results among groups, and two-way analysis of variance was used to evaluate the effects of grinding burs on final roughness (${\alpha}=.05$). RESULTS. The DP group had the highest final Ra value, followed by the DSP, NP, and NSP groups. Use of the stone grinding bur as a coarse-finishing step significantly decreased final Ra values when a diamond bur was used (P<.001). Omission of the stone grinding bur increased biofilm formation on specimen surfaces. Combining a stone grinding bur with silicone polishing burs produced the smallest final biofilm values, regardless of the use of a diamond bur in initial surface treatment. CONCLUSION. Coarse finishing of monolithic zirconia with a stone grinding bur significantly decreased final Ra values and bacterial biofilm formation when surfaces had been roughened by a diamond bur.

• Applied Science and Convergence Technology
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• v.24 no.5
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• pp.162-166
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• 2015

Linear ion beams have been introduced for the ion beam treatments of flexible substrates in roll-to-roll web coating systems. Anode layer linear ion sources (300 mm width) were used to make the linear ion beams. Oxygen ion beams having an ion energy from 200 eV to 800 eV used for the adhesion improvement of Cu thin films on PET substrates. The Cu thin films deposited by a conventional magnetron sputtering on the oxygen ion beam treated PET substrates showed Class 5 adhesion defined by ASTM D3359-97 (tape test). Argon ion beams with 1~3 keV used for the ion beam sputtering deposition process, which aims to control the initial layer before the magnetron sputtering deposition. When the discharge power of the linear ion source is 1.2 kW, static deposition rate of Cu and Ni were 7.4 and $3.5{\AA}/sec$, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1579-1583
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• 2013

Intercellular adhesion molecule-1 (ICAM-1) is a member of the immunoglobulin superfamily, its main function being to participate in recognition and adhesion between cells. ICAM-1 is considered closely related to occurrence, development, metastasis and invasion process of hepatocellular carcinoma (HCC). A variety of inflammatory cytokines and stimulus affect its expression through the nuclear factor-kappa B (NF-${\kappa}B$) signal transduction pathway. In the initial stage of inflammation, hepatocirrhosis and tumor development, ICAM-1 is expressed differently, and has varied effects on different cells to promote occurrence of malignancy and metastasis. ICAM-1 has diagnostic significance for AFP-negative or suspected HCC, and may be a prognositic significance. It is thus widely used in studies as a biomarker which reflects cancer cells metastasis as well as curative effect of drugs. Many new treatments of HCC may be based on the effects of ICAM-1 on different levels of function.