the molecular weight distribution of 4 commercial isotactic polypropylene (ipp) samples was estimated using rheological data. the dynamic moduli data, obtained from rheological measurements in linear viscoelastic region was used for calculation of relaxation time spectrum, h(τ) and then shear relaxation modulus, g(t). finally, applying thimm kernel function and relaxation modulus data in genera...

In this thesis a Mode Coupling Theory (MCT) equation is derived that calculates the shear modulus for multi-component colloidal mixtures in two-dimensional systems in linear approximation. With this equation, the plateau shear modulus G∞ is calculated for two two-dimensional systems at the glass transition: for a binary mixture of hard spheres and for a binary mixture of dipolar particles. The ...

Shear moduli variation in the metastable-stable structure transition of charged colloidal crystals was investigated by the combination techniques of torsional resonance spectroscopy and reflection spectrometer. Modulus of the system increases with the proceeding of the transition process and it finally reaches the maximum value at the end of the transition. For colloidal crystals in stable stat...

In this paper, a numerical solution has been developed for hollow circular cylinders made up of orthotropic material which is subjected to twist using micro polar theory. The effect of twisting moment and material internal length on hollow thick-walled circular cylinder made up of micro polar orthotropic material is investigated. Finite difference method has been used to exhibit the influence o...

This study presents a modified continuum model to investigate the vibration behavior of single and multi-carbon nanotubes (CNTs). Two parameters are exploited to consider size dependence; one derived from the energy equivalent model and the other from the modified couple stress theory. The energy equivalent model, derived from the basis of molecular mechanics, is exploited to describe size-depe...

We make a comparison between the concepts and physics behind Youngs double slit experiment ⋀-δ ⋁-δ type three level atoms producing quantum interference.

Tissues including liver stiffen and acquire more extracellular matrix with fibrosis. The relationship between matrix content and stiffness, however, is non-linear, and stiffness is only one component of tissue mechanics. The mechanical response of tissues such as liver to physiological stresses is not well described, and models of tissue mechanics are limited. To better understand the mechanics...

We have developed a soft-material elastic modulus and shear modulus sensor using piezoelectric cantilevers. A piezoelectric cantilever is consisted of a highly piezoelectric layer, e.g., lead– zirconate–titanate bonded to a nonpiezoelectric layer, e.g., stainless steel. Applying an electric field in the thickness direction causes a piezoelectric cantilever to bend, generating an axial displacem...

Introduction American chestnut (Castanea dentata (Marsh.) Borkh. once occurred over much of the eastern deciduous forests of North America (Russell, 1987), with a natural range exceeding 800,000 km (Braun, 1950) (Figure 1). Castanea dentata was a dominant tree species throughout much of its range, comprising between 25-50% of the canopy (Braun, 1950; Foster et al., 2002; Russell, 1987; Stephens...

We study the viscoelastic behavior of aqueous foam mixed with solid noncolloidal particles. We show that adding a tiny amount of grains can enhance the elastic and loss shear moduli by more than 1 order of magnitude. The scaling of these moduli with solid volume fraction is in qualitative agreement with that predicted by an effective-medium rigidity percolation model. We present a simple model,...