Friction characteristics with respect to surface topographic orientation were investigated using surfaces of different materials and fabricated with grooves of different scales. Scratching friction tests were conducted using a nano-indentation-scratching system with the tip motion parallel or perpendicular to the groove orientation. Similar friction anisotropy trends were observed for all the s...

After falls, skiers or snowboarders often slide on the slope and may collide with obstacles. Thus, the skier’s friction on snow is an important factor to reduce incidence and severity of impact injuries. The purpose of this study was to measure snow friction of different fabrics of ski garments with respect to roughness, speed, and contact pressure. Three types of fabrics were investigated: a c...

We report a quartz crystal microbalance study of the nanodynamical properties of tricresylphosphate (TCP) reaction films formed on high purity Fe, Cr, Fe oxide, and Cr oxide surfaces at elevated temperatures. The data reveal trace levels of interfacial slippage, potentially in conjunction with viscoelastic effects, for reaction films characterized by very low macroscopic friction coefficients. ...

We have examined the influence of rotation on the potential energy and the transport coefficients of the collective motion (friction and mass coefficients). For axially symmetric deformation of nucleus 224 T h we found that at excitations corresponding to temperatures T ≥ 1 M eV the shell correction to the liquid drop energy practically does not depend on the angular rotation. The friction and ...

The origin of friction comes from the atomic interaction at interfaces. Analytic theories indicated that there is no static friction on clean incommensurate interfaces, while a recent experiment revealed that the static friction coefficient was anisotropic with respect to the lattice orientation, but did not vanish on two clean Ni(100) mis-orientated surfaces. To understand this friction anisot...

During underground nuclear tests, rocks may fail by plastic yielding, which limits shear strength, or by tensile fracture, wherever maximum principal stress exceeds tensile strength. A third mode of failure exists due to friction along closed fractured surfaces. There, friction affects slipping and can thus limit stress. In this paper, we study the effect of friction on the simulated dynamic re...

A new analysis is presented of the relations between multicomponent friction coefficients and hydration numbers which describe non-ionic and multicomponent solutes transport in membranes in the framework of generalized Spiegler-Kedem-Katchalsky frictional model equations. In the framework of this model the expressions linking the permeability parameters of the membrane (Lp, sigma, omegaik) with...

A finite element program based on elastic –plastic model of Mohr-Coulomb criterion was used to evaluate the bearing capacity coefficients of soil under shallow strip flexible footing . The results were compared with others’ analytical results and it was found that the present study could offer quite consistent and rather precise values for the bearing capacity coefficients . The effect of d...