Motile dislocations knead odd crystals into whorls

Dislocations in Sodium-Chloride Crystals

Distributions of dislocations in sodium chloride crystals, which were induced by heat treatment or working, were investigated, using a newly developed etchant. The crystals, which were annealed above 3 0 0 ° C , showed reduced dislocation densities and rearranged dislocation patterns. By raising the temperature to 600 ° C or 700 ° C many elongated subboundaries or subboundaries arranged in the ...

Dislocations in crystals of silver halides

Dynamic self-assembly of motile bacteria in liquid crystals.

This paper reports an investigation of dynamical behaviors of motile rod-shaped bacteria within anisotropic viscoelastic environments defined by lyotropic liquid crystals (LCs). In contrast to passive microparticles (including non-motile bacteria) that associate irreversibly in LCs via elasticity-mediated forces, we report that motile Proteus mirabilis bacteria form dynamic and reversible multi...

Dislocations in cubic crystals described by discrete models

Discrete models of dislocations in cubic crystal lattices having one or two atoms per unit cell are proposed. These models have the standard linear anisotropic elasticity as their continuum limit and their main ingredients are the elastic stiffness constants of the material and a dimensionless periodic function that restores the translation invariance of the crystal and influences the dislocati...

Nonlinear theory of dislocations in smectic crystals: an exact solution.

It is shown that the strain field of an edge dislocation in a smectic crystal must be described in the framework of nonlinear theory, even far away from the core region. We present an exact solution of this nonlinear problem. The result of the linear theory is recovered in the limit of large bending rigidity.