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Abstract: Organic–inorganic hybrid coatings, obtained through the sol–gel chemistry from tetraethoxysilane and polyethylene–poly(ethylene glycol) block copolymer, have been prepared in different compositions and applied to untreated and plasma treated LDPE films by spin coating. The mechanical properties of the coatings and the adhesion between coating and substrate have been characterized by fragmentation test. An increase in coating strength, elongation at break and adhesion has been observed with increasing the organic fraction in the hybrid coating. A plasma treatment of the LDPE surface, just before the application of the coating, lead to an increase of the adhesion between coating and substrate (interfacial shear strength), leaving almost unaffected coating strength and strain at fragmentation onset. [Copyright &y& Elsevier]

Abstract: Concentrations of trace elements (Hg, Cd, Pb, Zn, Cu, Fe, and Se) in different organs and tissues (liver, kidney, muscle tissue, spleen, heart, lung, and fat tissue) of loggerhead turtles Caretta caretta from eastern Mediterranean Sea were determined. The highest levels of mercury and cadmium were found in liver (Hg: 0.43μgg-1 wet weight; Cd: 3.36μgg-1 wet weight) and kidney (Hg: 0.16μgg-1 wet weight; Cd: 8.35μgg-1 wet weight). For lead the overall concentrations were low and often below the limit of detection. Copper and selenium tended to be higher in liver than in other tissues and organs, while for zinc the concentrations were quite homogenous in the different organs and tissues, except fat tissue (64.7μgg-1 wet weight) which showed a higher accumulation of this element. For iron the greatest concentrations were observed in liver (409μgg-1 wet weight) and spleen (221μgg-1 wet weight). [Copyright &y& Elsevier]

Filled elastomers are widely used in components within the gas infrastructures. Currently, it is necessary to evaluate their suitability to harsh conditions of temperature and pressure required by the hydrogen applications. The effect of the environmental conditions on the material mechanical response (up to fracture) has been evaluated, by performing tests at different temperatures or under pressurized hydrogen, on three carbon black-filled acrylonitrile butadiene rubbers. With the increase of temperature, the fracture resistance resulted to decrease and the crack advancement rate increased. If the gas pressure applied during testing increases, the fracture toughness evaluated at the onset of unstable crack propagation increases while the crack advancement rate decreases. Some effects related to the gas type (hydrogen or nitrogen) were also observed. Moreover, if the material was previously exposed to pressurized hydrogen, no effects on the mechanical response were observed. • The effect of environment on mechanical behaviour of elastomers was evaluated. • With increasing temperature, the fracture resistance decreased. • If the material was previously exposed to hydrogen, no effects were observed. • The fracture behaviour was affected by the applied gas pressure during testing. • The gas type also had some effects on the material fracture behaviour. [ABSTRACT FROM AUTHOR]