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Luminescent oxygen sensor composed of platinum-porphyrin and a gas-permeable polymer binder was applied as an optical crack sensor paint for infrastructure. The sensor paints were designed as a three-layered structure in which the luminescent oxygen sensor layer was sandwiched between oxygen barrier layers. The sensor paints emitted intense luminescence under UV light irradiation, and the luminescence was efficiently quenched when a new crack formed on the concrete surface. Microcracks, which were

Surface protection by hydrophobic impregnation and surface coating are widely used for concrete bridges located at coastal area in Japan. This paper deals with the improvement of adhesion between surface coating and hydrophobic impregnated concrete by different types of silanes and by invastigating surface treatment methods. As a result, adhesion between hydrophobic impregnated concrete and epoxy-based surface coating were improved by applying abrasive paper, portable electric grinder, solvent or diluted hydrochloric acid treatment. Especially, using portable electric grinder gave a remarkable improvement to the adhesive property. Also, hybrid-surface protection system consisting of surface coating and hydrophobic impregnation was discussed to prevent blistering.

The ultrasonic welding of polymer optical fibres (POFs) onto carbon-fibre-reinforced polymers for advanced fibre-optic sensing is demonstrated. The relationships among the welding time, preload, optical loss, and adhesive force are fully evaluated. A high-speed camera to monitor changes in the cross section of the POF during the ultrasonic welding is also used.

Fibre-reinforced polymers (FRPs) have been widely used for reinforcement of existing structures due to its light weight and high corrosion resistance. Several hundred examples in the world show tha...

We will present a simple and low cost method to visualize local strain distribution in deformed aluminum plates. In this study, aluminum plates were coated with opal photonic crystal film with tunable structural color. The photonic crystal films consist of a silicone elastomer that contains an array of submicron polystyrene colloidal particles. When the aluminum sheets were stretched, the change in the spacing of the colloidal particles in the opal film alters the color of the film. This approach could be useful as a new strain gauge having a visual indicator to detect mechanical deformation.

Hexavalent chromium is sometimes eluted from cement concrete recycled base course material. Therefore, hexavalent chromium eluted restraint technology is developed. The concentration analysis of hexavalent chromium is difficult, when a reducer coexists. There were not that standard measurement methods. The authors have already developed the analysis method of hexavalent chromium when a return substance coexists. When using this way, even if there is a return substance, hexavalent chromium is measured right. So hexavalent chromium reduction technologies were studied using accessible materials. As a result, hexavalent chromium eluted restraint technologyreducing sugar has been developed. セメントコンクリート再生路盤材からは六価クロムが溶出する可能性があるため，溶出の確認が行われるようになっている．これに伴い，六価クロム溶出低減技術も開発されるようになっているが，還元物質を用いる対策の場合，JISの分析法を用いることができず，評価が難しいのが現状である．本研究では，独自に開発した還元物質共存下でも容易に六価クロムを分析できる方法を用いて，自然由来の物質や入手が容易な物質の中から，還元効果が期待できる物質を選定し，六価クロムの溶出低減効果を検討した．その結果，比較的入手が容易な一部の果汁や還元糖の中に六価クロム溶出低減効果が高いものがあることを把握した．

N-Benzoyl L-daunosamine was synthesized stereoselectively starting from O-t-butyldimethylsilyl L-lactaldehyde and methyl propiolate; the crucial step, intramolecular conjugate addition of a carbamoyl amino group of methyl threo-5-carbamoyloxy-4-triethylsilyloxy-(Z)-hex-2-enoate, proceeded with exclusive 1,3-anti diastereoselectivity.