in this work, the mechanism for fracture of brittle substances such as rocks under a uniform normal tension is considered. the oriented straight micro-cracks are mostly created in all the polycrystalline materials resulting from the stress concentrations. the present work focuses on the interactions of the pre-existing micro-cracks, which can grow and propagate within a rock-like specimen. the ...

Ascorbate peroxidase (E 1.11.1.11) acts as primary key component of plant defense against photo protection and photo-oxidative stress. Chloroplastic (APX) located in the thylakoid membrane (tAPX) and stroma (sAPX) have been thought to be key regulators of intracellular levels of H2O2. Therefore, it is of interest to study thylakoid membrane bound SlAPX from Solanum lycopersicum (tomato, a flesh...

Thermo-elastic analysis of a functionally graded hollow sphere is carried out and numerical solutions of displacement, stress and thermal fields are obtained using the Polynomial differential quadrature (PDQ) method. Material properties are assumed to be graded in the radial direction according to a power law function, ho...

A low-energy electron microscopy study of two-dimensional Si~001! island shapes near thermal equilibrium on 10315 mm large single-domain terraces reveals a continuous increase of island aspect ratio and a shape transition from elliptical to ‘‘American-football’’-like with increasing island size. The size-dependent island shapes are driven by elastic relaxation caused by the intrinsic surface st...

This paper presents a study of 3D deformation process in a dry packing of Ottawa sand. X-ray microtomography is used to acquire scans of a triaxial test of the sample at five axial stress levels. Using 3D image analysis we are able to resolve particle scale features. Particle tracking combined with finite element simulations reveal that the rotational transformation of particles is one of the p...

The algorithmic consistency conditions are derived which yield the plastic loading index for the combined isotropic– kinematic hardening plasticity with the Armstrong–Frederick evolution equation for the back stress. Rate-independent elastic–plastic, and rate-dependent viscoelastic–plastic and elastic–viscoplastic material models are all encompassed by the analysis. The directions of the plasti...

Even if a ‘complete set’ of experimental observables were measured for the elastic scattering or photo/electroproduction of pseudoscalar mesons, ambiguities would remain in the extracted partial-wave and isospin decomposed amplitudes. As these problems are not widely understood, the present work outlines the way model-dependence enters into analyses of data from both hadronic and electromagneti...

A method is presented for the stress analysis of flight vehicles under different flight conditions including gust and control surface deflection (or maneuver) using the governing equations of rigid-body motions and elastic deformations. The Lagrangian approach is used to derive the governing equations of motions. For this purpose, the basic equations of motions are derived in terms of potential...

An analytical method for predicting elastic–plastic stress distribution in a cylindrical pressure vessel has been presented. The vessel material was a ceramic/metal functionally graded material, i.e. a particle–reinforcement composite. It was assumed that the material’s plastic deformation follows an isotropic strain-hardening rule based on the von-Mises yield criterion, and that the vessel was...