This study focuses on achieving high stiffness/strength and good FR characteristic of nylon 66/MCA/NC nanocomposites, prepared via melt compounding by twin screw extruder. A synergistic effect of flame retardant systems based on melamine cyanurate and zinc borate on the flammability and mechanical behaviours of crysnanoclay reinforced nylon 66 nanocomposites have been reported. Mechanical test ...

Chatter is a concern in boring process, due to the low dynamic stiffness of long cantilever boring bars. Chatter suppression in machining permits higher productivity and better surface finishes. The MR fluid, which changes stiffness and undergoes a phase transformation when subjected to an external magnetic field, is applied to adjust the stiffness of the boring bar and suppress chatter. The st...

this paper examines differences in performances of a range of torsionally stiff and flexible single story buildings designed with the provisions of iranian standard 2800. seismic nonlinear dynamic time history behavior of eight building models subjected to seven horizontal bi-directional design spectra compatible ground motions are investigated. these models cover a wide range of very torsional...

In this study, a dynamic stiffness method for free vibration analysis of moderately thick function-ally graded material plates is developed. The elasticity modulus and mass density of the plate are assumed to vary according to a power-law distribution in terms of the volume fractions of the constituents whereas Poisson’s ratio is constant. Due to the variation of the elastic properties through ...

In this study, the finite element model updating was simulated by reducing the stiffness of the members. Due to lack of access to the experimental results, the data obtained from an analytical model were used in the proposed structural damage scenarios. The updating parameters for the studied structures were defined as a reduction coefficient applied to the stiffness of the members. Parameter v...

The dynamic stiffness of excised cardiac muscles that would be likely to have different intrinsic speeds of contraction, as judged by previous biochemical reports of their myosin ATPase rates, was compared. This study included muscles from thyrotoxic rabbits and newborn rabbits, rabbit atria, and normal papillary muscles at different temperatures. The usual excitation-contraction coupling proce...

Many studies simulates the machining process by using a single degree of freedom springmass sytem to model the tool stiffness, or the workpiece stiffness, or the unit toolworkpiece stiffness in modelings 2D. Others impose the tool action, or use more or less complex modelings of the efforts applied by the tool taking account the tool geometry. Thus, all these models remain two-dimensional or so...

Liver stiffness was measured by transient elastography (FibroScan) in 228 consecutive patients with chronic viral hepatitis, with (115) or without cirrhosis (113), to study its correlations with serum transaminases [alanine aminotransferase (ALT)], fibrosis stage and surrogate noninvasive markers of fibrosis (APRI, FORNS, FibroTest and hyaluronic acid). The dynamic profiles of serum transaminas...

  In this article, vibration analysis of an Euler-Bernoulli beam resting on a Pasternak-type foundation is studied. The governing equation is solved by using a spectral finite element model (SFEM). The solution involves calculating wave and time responses of the beam. The Fast Fourier Transform function is used for temporal discretization of the governing partial differential equation into a se...