Optimization and characterization of tungsten thick coatings on copper based ally substrates

Tungsten is a promising armour material for plasma facing components of nuclear fusion reactors because of its low sputter rate and favourable thermo-mechanical properties. Among all the techniques able to realise W armours, plasma spray looks particularly attractive owing to its simplicity and low cost. The present work concerns the optimisation of spraying parameters aimed at 4–5 mm thickWcoating on copper–chromium–zirconium (Cu,Cr,Zr) alloy substrates. Characterisation of coatings was performed in order to assess microstructure, impurity content, density, tensile strength, adhesion strength, thermal conductivity and thermal expansion coefficient. The work performed has demonstrated the feasibility of thick W coatings on flat and curved geometries. These coatings appear as a reliable armour for medium heat flux plasma facing component

In Venice and in the Veneto with Ernest Hemingway

a guide to Hemingway's Venice and the region of the Veneto, from his early work to his late novel

Mapping tooth mechanical properties by FIMEC tests

Dentin has different morphology near the enamel and in the inner part, resulting in mechanical properties progressive changing in correspondence of structure variation. In order to obtain a local mechanical characterization of dentin, FIMEC (Flat-top cylinder Indenter for mechanical characterization),1 an instrumented indentation technique, has been employed. FIMEC uses a cylindrical punch and permits local measurements of Young’s modulus E, yield stress Y, stress-relaxation and creep. The punch diameter (Φ = 0.5 mm) is much larger than the tubule size thus data are not so largely scattered as in micro- and nano-indentation tests but, at the same time, is small enough to guarantee a good resolution in mapping the mechanical properties in different tooth positions. More details about the FIMEC test and its application for measurements on human teeth can be found in Cappelloni et al. (2010)

Pressure effect in ethanol steam reforming via dense Pd-based membranes

The ethanol steam reforming reaction has been performed in a membrane reactor consisting of a Pd–Ag tube (wall thickness 150 micrometers) filled with a Ru-based catalyst. The experiments have permitted to characterize the Pd–Ag permeator in terms of both hydrogen permeability and yield of the steam reforming reaction at temperature of 400 and 450 ◦C in the pressure range 100–800 kPa. The permeation tests exhibited hydrogen permeability values in agreement with the literature and the complete hydrogen selectivity. In the reaction tests, water/ethanol mixtures of molar ratio 10/1 and flow rates of 5, 10 and 15 g h−1 have been fed in the lumen side of the membrane tube while the permeated hydrogen has been collected in the shell side by a nitrogen sweep stream. At 450 ◦C with a reaction pressure of about 400 kPa and a water/ethanol feed flow rate of 5 g h−1, maximum values of hydrogen yield (5.5) and hydrogen recovery factor (close to 100) have been measured. The hydrogen yield reduces at lower temperatures and pressures as well as when larger water/ethanol flow rates are fed (10 and 15 g h−1). Finally, a simulation code based on a simplified reaction kinetics has been developed: the comparison with the results of the tests permitted to determine the parameters of such a kinetics. A model analysis of the membrane reformer aimed at verifying the influence of the main operating parameters has been carried out, too