Epitaxial Ba0.6Sr0.4TiO3 films were grown onto ~001! LaAlO3 by pulsed-laser deposition, and the dislocation structures of the films were investigated using transmission electron microscopy. Misfit dislocations with a periodicity of about 7 nm and Burgers vectors b5a^100& were observed at the interface. A high density of threading dislocations was present the films and these also had b 5a^100& ....

A significant increase of the drain current appears if defined arrangements of dislocations are present in the channel of MOSFETs. Furthermore, analyses of the electronic properties of individual defects refer to a supermetallic behavior of dislocations. The reason is the extremely high strain in the dislocation core exceeding values of effi 0.1. Such high strain causes substantial changes of t...

We study the existence of dislocations in an anisotropic Swift-Hohenberg equation. We find dislocations as traveling or standing waves connecting roll patterns with different wavenumbers in an infinite strip. The proof is based on a bifurcation analysis. Spatial dynamics and center-manifold reduction yield a reduced, coupled-mode system of differential equations. Existence of traveling dislocat...

Plasticity in magnesium crystals oriented for c-axis compression has been usually attributed to 〈cþa〉 dislocation slip on second-order pyramidal {112̄2} planes. Through molecular dynamics simulations, we investigated the formation and slip characteristics of 〈cþa〉 dislocations on second-order pyramidal planes. It is shown that the critical c-axis compressive stress for these dislocations is almo...

DISLOCATION of the scaphoid is a rare injury of which only a few reports of its occurrence appear in the literature. These include Higgs (1930), two cases; Buzby (1934); Kuth (1939); Wood-Walker (1943); Schlossbach (1954) and Connell & Dyson (1955), all reporting single cases. Russell (1949), in a review of intercarpal dislocations and fracture dislocations reported only one case of dislocation...

It is shown that the random electric fields of charged dislocations in insulators should cause appreciable broadening of sharp resonance lines such as spin-resonance signals. The degree of broadening is very sensitive to the screening of the dislocations by charged point defects. Since the shape of the inhomogeneously broadened resonance line monitors the distribution of the internal fields, th...

The movement of dislocations in a crystal is the key mechanism for plastic deformation in all materials. Studies of dislocations have focused on three-dimensional materials, and there is little experimental evidence regarding the dynamics of dislocations and their impact at the atomic level on the lattice structure of graphene. We studied the dynamics of dislocation pairs in graphene, recorded ...

This review on elbow dislocations describes ligament and bone injuries as well as the typical injury mechanisms and the main classifications of elbow dislocations. Current treatment concepts of simple, that is, stable, or complex unstable elbow dislocations are outlined by means of case reports. Special emphasis is put on injuries to the medial ulnar collateral ligament (MUCL) and on posttrauma...

tit r* -By F. J. Cotton. vv. a. Saunders & Co. Under this title Dr. Frederick Cotton has compiled a text-book on the subject of injuries to bones and joints which should certainly take its place as a standard work. The author has amply illustrated his subject, and in fact relies on illustration almost as much as letter press to make his subject clear, for in GOO odd pages there are 1,200 or mor...

Metals with nanoscale twins have shown ultrahigh strength and excellent ductility, attributed to the role of twin boundaries (TBs) as strong barriers for the motion of lattice dislocations. Though observed in both experiments and simulations, the barrier effect of TBs is rarely studied quantitatively. Here, with atomistic simulations and continuum based anisotropic bicrystal models, we find tha...