introduction: although left ventricular(lv) function parameters measured by gated myocardial perfusion spect (gspect) have been validated, experimental data have revealed that the calculated the lv function parameters using gspect are affected by patient populations as well as particular acquisition and processing conditions. we tried to determine the normal values of gspect in an iranian popul...

two different dual phase steels were prepared from low carbon manganese steel after the eliminationof the banding using the direct quenching (dq) and the step quenching (sq) procedures. different heattreatments resulted in different martensite morphologies, microstructures and mechanical properties. theheat treatments were designed in such a way to obtain a 0.25 volume fraction of martensite (v...

By increase in the power of computer systems and enhanced power of the components and their temperature, including the central processing unit (CPU), cooling just by the air is not effective and there is need for more powerful systems to cool down and increase the power of the cooling system. In this article simulation of the heat exchanger material of the fluid cooling system has been studied ...

a numerical study has been done through an al2o3–water in a double lid-driven  square  cavity with various  inclination  angles  and discrete heat sources. the top and right moving walls are at low temperature. half of  the  left and bottom walls are  insulated and  the  temperatures of the other half are kept at high. a large number of simulations for a wide  range  of richardson  number  of  ...

Number of complex fluids (as slurries, drilling muds, paints and coatings, many foods, cosmetics, biofluids...) can approximately be described as concentrated dispersions of Structural Units (SUs). Due to shear forces, SUs are assumed to be approximately spherical in shape and uniform in size under steady flow conditions, so that a complex fluid can be considered as a roughly monodisperse dispe...

We investigate the nature of randomness in disordered packings of frictional spheres. We calculate the entropy of 3D packings through the force and volume ensemble of jammed matter, a mesoscopic ensemble and numerical simulations using volume fluctuation analysis and graph theoretical methods. Equations of state are obtained relating entropy, volume fraction and compactivity characterizing the ...

Colloidal particles interacting via a long-range repulsion can, in contrast to hard-sphere systems, exhibit crystalline ordering at low volume fraction. Here we experimentally investigate the structure and properties of such "colloidal Wigner crystals." We find a body-centered-cubic crystalline phase at volume fractions of ϕ≳15%, which exhibits large fluctuations of individual particles from th...

The rheological data of weakly attractive colloidal particles are shown to exhibit a surprising scaling behavior as the particle volume fraction, straight phi, or the strength of the attractive interparticle interaction, U, are varied. There is a critical onset of a solid network as either straight phi or U increase above critical values. For all solidlike samples, both the frequency-dependent ...

We investigate the capture of particles in soft porous media. Liquid foam constitutes a model system for such a study, allowing the radii of passage in the pore space to be tuned over several orders of magnitude by adjusting the liquid volume fraction. We show how particle capture is determined by the coupling of interstitial liquid flow and network deformation, and present a simple model of th...

We numerically produce fully amorphous assemblies of frictionless spheres in three dimensions and study the jamming transition these packings undergo at large volume fractions. We specify four protocols yielding a critical value for the jamming volume fraction which is sharply defined in the limit of large system size, but is different for each protocol. Thus, we directly establish the existenc...