In a previous experimental study, it was observed that the break-through process of a cleavage front across a high-angle grain boundary can be highly nonuniform. While the central part of the boundary can be cleaved quite smoothly, the rest parts must be sheared apart. In this paper, the trapping effect of grain boundary shearing is analyzed in considerable detail. Before the shearing is comple...

The paper deals with the design of cognitive artefacts. It is supported that both normative and descriptive design approaches fail to acknowledge the co-adaptation between users and artefacts; this leads to the so-called design paradox and obstructs the co-evolution of practice and artefacts. In the first section, the paper discusses the task-artefact cycle and presents examples showing that th...

The purpose of this paper is to analysis the viscoelastic models under dynamic loading. A five-parameter model is chosen for study exhibits elastic, viscous, and retarded elastic response to shearing stress. The viscoelastic specimen is chosen which closely approximates the actual behavior of a polymer. The module of elasticity and viscosity coefficients are assumed to be space dependent i.e. f...

The aim of this research was to investigate how growth hormone (GH) cortisol and some haematochemical parameters could be modified by the stress caused by the stages of shearing in Sarda breed sheep. Five groups of 10 sheep each were formed. Group A, only separated from the flock; Group B, only tied; Group C, both tied and shorn (animals in these three groups were ewe lambs shorn for the first ...

OBJECTIVE To study the degradation and basic fibroblast growth factor (bFGF) release activity of bFGF - poly(lactic-co-glycolic-acid) microsphere (bFGF-PLGA MS) under stress in vitro, including the static pressure and shearing force-simulating mechanical environment of the joint cavity. METHOD First, bFGF-PLGA MSs were created. Meanwhile, two self-made experimental instruments (static pressur...

in the present study, shearing properties of sugar cane stems were determined at five moisture content levels (46, 54, 62, 70 and 78% wb), three shearing speed (5, 10 and 15 mm min-1) and at ten positions on the stem. for measuring the shearing forces, the stems were severed by using a computer aided cutting apparatus. decrease in moisture content of stem from 78 to 46% wb led to 16.3 and 16.7%...

A stress fracture of the scaphoid combined with distal radial epiphysiolysis occurred in a 16 year old badminton player. Repeated shearing and torsional forces by excessive wrist movement from hitting a shuttle probably cause stress injuries in both the scaphoid and the distal radius.