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Adhesive Layer (adhesive + layer)
Selected AbstractsCalcite-specific coupling protein in barnacle underwater cementFEBS JOURNAL, Issue 24 2007Youichi Mori The barnacle relies for its attachment to underwater foreign substrata on the formation of a multiprotein complex called cement. The 20 kDa cement protein is a component of Megabalanus rosa cement, although its specific function in underwater attachment has not, until now, been known. The recombinant form of the protein expressed in bacteria was purified in soluble form under physiological conditions, and confirmed to retain almost the same structure as that of the native protein. Both the protein from the adhesive layer of the barnacle and the recombinant protein were characterized. This revealed that abundant Cys residues, which accounted for 17% of the total residues, were in the intramolecular disulfide form, and were essential for the proper folding of the monomeric protein structure. The recombinant protein was adsorbed to calcite and metal oxides in seawater, but not to glass and synthetic polymers. The adsorption isotherm for adsorption to calcite fitted the Langmuir model well, indicating that the protein is a calcite-specific adsorbent. An evaluation of the distribution of the molecular size in solution by analytical ultracentrifugation indicated that the recombinant protein exists as a monomer in 100 mm to 1 m NaCl solution; thus, the protein acts as a monomer when interacting with the calcite surface. cDNA encoding a homologous protein was isolated from Balanus albicostatus, and its derived amino acid sequence was compared with that from M. rosa. Calcite is the major constituent in both the shell of barnacle base and the periphery, which is also a possible target for the cement, due to the gregarious nature of the organisms. The specificity of the protein for calcite may be related to the fact that calcite is the most frequent material attached by the cement. [source] Boundary element analysis of curved cracked panels with adhesively bonded patchesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 1 2003P. H. Wen Abstract A new boundary element formulation for analysis of curved cracked panels with adhesively bonded patches is presented in this paper. The effect of the adhesive layer is modelled by distributed body forces (i.e. two in-plane forces, two moments and one out-of-plane force). A coupled boundary integral formulation of a shear deformable plate and two-dimensional plane stress elasticity is used to determine bending and membrane forces along the adhesive layer taking into consideration the compatibility conditions in the patch area. Two numerical examples are presented to demonstrate the efficiency of the proposed method. It is shown that the out-of-plane bending behaviour and panel curvature have significant influence on the magnitude of the stress intensity factors. Copyright © 2003 John Wiley & Sons, Ltd. [source] Application of two-state M -integral for analysis of adhesive lap jointsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 9 2001Yongwoo Lee Abstract With the aid of the two-state M -integral and finite element analysis, the asymptotic solution in terms of the complete eigenfunction expansion is obtained for adhesive lap joints. The notch stress intensity is introduced to characterize the singular stress field near the notch vertex of adhesive lap joints. The proposed scheme enables us to extract the intensity of each eigenfunction term from the far field data without resort to special singular elements at the vertex. It turns out that a weak stress singularity is not negligible around the vertex when it exists in addition to the major singularity. For a thin adhesive layer, there exist two asymptotic solutions: one is the inner solution approaching the eigenfunction solution for the vertex at which the adherend meets with the adhesive and the other is intermediate solution represented by the eigenfunction series that would be obtained in the absence of the adhesive layer. An appropriate guideline for choosing the geometric parameters in designing the adhesive lap joints, particularly the overlap length or the size of the adhesive zone, is suggested from the viewpoint of minimizing the notch stress intensity. Copyright © 2001 John Wiley & Sons, Ltd. [source] Attack of the artillery fungus on vinyl sidingJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 2 2005Richard F. Grossman The artillery fungus, Sphaerobolus stellatus, ejects dark-colored spores for a distance of several meters. These are enclosed in an adhesive layer comprised of carotenoid pigments. On exposure to sunlight, the pigment layer resinifies and develops a strong bond to vinyl siding capstock. The damage is compounded when the homeowner removes the bonded spores abrasively, destroying the protective capstock layer. Strategies to protect vinyl siding or to defeat the microorganism are discussed. J. VINYL. ADDIT. TECHNOL., 11:63,64, 2005. © 2005 Society of Plastics Engineers [source] Numerical investigation of the influence of material properties and adhesive layer thickness on the heating efficiency of microwave curing of an adhesive-bonded jointPOLYMER ENGINEERING & SCIENCE, Issue 8 2004H. W. So In the process of microwave curing of an adhesive-bonded joint, both the adhesive layer and the adherends affected the heating efficiency of the joint. As an extension of previous studies, the influences of changing the properties of the components of the joint on the heating efficiency were predicted by simulations that were based on the numerical model developed previously. The influence of adhesive thickness was also studied. The properties that directly affected power dissipation and heat loss of the adhesive layer were found to be important to the heating efficiency of the process. The heating rate was also sensitive to the thickness of the adhesive layer. Polym. Eng. Sci. 44:1414,1418, 2004. © 2004 Society of Plastics Engineers. [source] Effect of hybrid network formation on adhesion properties of polycyanurate/polyurethane semi-interpenetrating polymer networksPOLYMER ENGINEERING & SCIENCE, Issue 12 2002O. Grigoryeva The adhesion characteristics of modified polycyanurates based on the principle of semi-interpenetrating polymer networks (semi-IPNs) have been studied. It has been shown that the formation of a polycyanurate network in the presence of linear polyurethane (LPU) leads to increasing adhesion strength to aluminum and titanium. The peculiarities of polycyanurate network (PCN) formation in the presence of different amounts of LPU are discussed. It has been found that chemical incorporation of LPU into PCN occurs during network formation owing to chemical interaction of urethane groups with cyanate groups of growing PCN. At LPU content in the initial composition up to around 20 wt% only a hybrid network is formed. The maximal values of adhesive strength to aluminum and titanium are achieved at LPU content of 20,25%, corresponding to formation of a hybrid network. The further increase of LPU content leads to the presence of non-incorporated LPU (semi-IPN formation) in the adhesive layer and to reduction of the adhesive strength. [source] |