Deformation of polymers under friction loading

A study has been made of the laws of distribution of elastic and residual deformations in the surface layers of polymers subjected to friction. The dependence of these deformations on normal pressure, sliding velocity, and duration of loading has been determined. A relation between deformation and antifriction characteristics has been established, and the relative effect of normal and tangential loads on surface-layer deformation determined.Mekhanika Polimerov, Vol. 3, No. 3, pp. 539–543, 1967     

Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts

We show that, contrary to intuition, small (< or =1 microm) transparent particles can be trapped and manipulated in a nematic liquid crystal using an intense laser beam, although their index of refraction is lower than both refractive indices of the surrounding birefringent fluid. Two mechanisms are identified that are responsible for this anomalous trapping: (i) surface-induced distortion of the birefringent media around the particle, creating a high-index "cloud" around the colloid, and (ii) laser-induced distortion or (partial) melting of a nematic, creating a ghost colloid.