It is well known that pebble diameter systematically decreases downstream in rivers. The contribution of abrasion is uncertain, in part because (1) diameter is insufficient to characterize pebble mass loss due to abrasion and (2) abrasion rates measured in laboratory experiments cannot be easily extrapolated to the field. A recent geometric theory describes abrasion as a curvature-dependent pro...

introduction: animal models of parkinson’s disease (pd) with partial damage of nigrostriatal dopaminergic system are very suitable for development of treatment strategies. although drug-induced rotational behavior has been conventionally used for analysis of lesioned animals, but bcause of the development of sensitization, it is necessary to invent a pure behavioral test that can evaluate such ...

BACKGROUND In the repair process achieving high bond strength between the new and old resin based materials is necessary for clinical longevity. This study compared the effect of three different mechanical surface treatments (air abrasion, Nd:YAG laser and diamond bur) on the repair bond strength of giomer. MATERIAL AND METHODS In this in vitrostudy, 125 cylindrical giomer samples were used. ...

in this study, friction stir spot welding (fssw) is applied to join the tial6v4 titanium alloy with 1.5 mm thickness and then the effect of rotational speed and tool dwell time on microstructure and mechanical properties is investigated. in this regard, the speed of the tool rotation was considered as 800, 1000, and 1200 rpm, as well as the tool dwell time was set at 7 and 12s. microstructural ...

An important factor in material quality is the time duration that materials are used (known as substance lifetime). Lifetime is a function of several factors, and among them wearing and abrasion resistances are more important than the other aspects. In addition, to the physical and mechanical properties, abrasion has a significant effect on the textiles appearance. This phenomenon considerably ...

In this paper, the metal matrix composites containing 22 wt % Cr, 2.5 wt % C and 2 to 16  volume percent TiC were processed by solidifying Fe-Cr-Ti-C in which precipitation of titaniumcarbide and chromium carbide occurred. The microstructure and abrasion resistance of in-situ synthesized composites were compared with the unreinforced high chromium white cast iron (HCWCI) containing 22 w. t. % C...