To visualize the grain boundary role on the shape memory property of Cu-Zn-A1 alloy, we have followed the austenitic structure evolution, of crystals submitted to a training treatment, by synchrotron X-ray topography in white beam. Single crystals, tricrystals and polycrystalline samples have been studied. The comparison of results shows that in polycrystalline samples large, non recoverable st...

The shape of wake behind a wind turbine is normally assumed to have a hat shape for the models used in wind farm layout optimization purposes; however, it is know from experimental tests and numerical simulations that this is not a real assumption. In reality, the results of actual measurements and detailed numerical simulation show that the velocity in wake region has a S-shape profile. Th...

We study through numerical simulations the dependence of the hydraulic permeability of granular materials on the particle shape and the grain size distribution. Several models of sand are constructed by simulating the settling under gravity of the grains; the friction coefficient is varied to construct packs of different porosity. The size distribution and shapes of the grains mimic real sands....

We develop a comprehensive quantitative description of the cross-section mechanism discovered several years ago by Lazarian. This is one of the processes that determine grain orientation in clouds of suprathermal cosmic dust. The crosssection mechanism manifests itself when an ensemble of suprathermal paramagnetic granules is placed in a magnetic field and is subject to ultrasonic gas bombardme...

In winter wheat, grain development is asynchronous. The grain number and grain weight vary significantly at different spikelet and grain positions among wheat cultivars grown at different plant densities. In this study, two winter wheat (Triticum aestivum L.) cultivars, 'Wennong6' and 'Jimai20', were grown under four different plant densities for two seasons, in order to study the effect of pla...

Grain boundary mobility and grain-liquid boundary mobility in ceramics vary vastly from material to material. Their characteristics are sensitive to the crystal structure, the nature of bonding, orientation, stoichiometry and composition. More directly, mobility can be lowered by decreasing the interfacial energy and anisotropy or increasing solute drag, liquid viscosity, particle pinning and g...

We propose a simple model for density fluctuations of aerodynamic grains, embedded in a turbulent, gravitating gas disc. The model combines a calculation for the behaviour of a group of grains encountering a single turbulent eddy, with a hierarchical approximation of the eddy statistics. This makes analytic predictions for a range of quantities including: distributions of grain densities, power...