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Abstract: To improve the physiochemical properties of bio-patch materials, silver compounds of various concentrations were synthesized in chitosan solution and formed to silver hybridized porous chitosan structures. We examined various properties such as morphology, crystallization intensity, mechanical strength, hydrophilic ratio and drug-delivery efficiency. We ascertained that it was optimal to combine silver nitrate of 3%, chitosan of 1% (molecular weight <1000kDa), and sodium borohydride of 0.003% for achieving high mechanical strength and drug-delivery efficiency. Drug release rate and hydrophilic ratio was increased due to silver concentration increment. Further, the initial drug release of the silver hybridized porous chitosan patch was approximately 1.5 times faster than that of the chitosan patch as control. These results indicate that silver hybridized porous chitosan patch can be widely used as sterilizing transdermal drug-delivery system (TDDS) in various fields. [Copyright &y& Elsevier]

Highlights: [•] The quantity of residual strains of metal-coated FBG sensors depends on the mechanical properties of the metal coating. [•] Metal-coated FBG sensors were fabricated by molten tin through a dipping method. [•] Cyclic loading tests for FBG sensors were performed to explore their capability of producing permanent residual strains. [•] The tensile strength of tin-coated FBG sensors was investigated by tensile tests right after the cyclic loading tests. [•] The results of mechanical property tests can be used as guidelines for the installation of tin-coated FBG sensors. [Copyright &y& Elsevier]

Abstract: A determination technique for the maximum strains experienced by composites is proposed using the permanent deformation characteristics of elasto-plastic metal-coated optical fiber sensors (OFSs). In order to confirm their feasibility, both analytical and experimental approaches were undertaken. In the analysis, a theoretical model for a surface-mounted OFS on the composite was proposed, and the strain transfer relations were derived. Moreover, novel numerical methods were implemented in order to evaluate the residual strain distribution. The analytical results were validated through a finite element analysis (FEA) using the ABAQUS software. We found that the residual strain increases as the coating thickness and external strain increase. In addition, the required gauge length for the given bonding length of the OFSs is proposed. In the experiment, fiber Bragg grating (FBG) sensors were applied to carbon fiber reinforced polymer (CFRP) composite specimens in order to verify the proposed technique. The trends of the residual strain, which are corresponding to the maximum strains experienced by the composite specimens, were consistent with those obtained in the analysis. [Copyright &y& Elsevier]