Sharif Digital Repository

Effects of Fe particle volume percent (from 0 to 5%) and changing the tool rotation direction in each pass were studied on the microstructure evolution and mechanical properties of the in situ Al/intermetallic composites produced by three passes friction stir processing (FSP) with ∼10 µm Fe particles. Optical and scanning electron microscopes were used for the investigation of the composite homogeneity, formation of Al–Fe intermetallic compounds, and fracture surfaces. Tensile and microhardness tests were also carried out to evaluate the mechanical properties of the composites. Solid-state reactions between the aluminum matrix and Fe particles led to in situ formation of Al3Fe and Al5Fe2... 

The cell membrane is responsible for the transportation of heat between inside and outside the cell. Whether the thermal properties of the cell membrane are affected by the cholesterol concentration or the membrane proteins has not been investigated so far. Although the experimental measurement of the membrane thermal conductivity was not available until very recently, computational methods have been widely used for this purpose. In this study, we carry out molecular dynamics simulations to investigate the relation between the concentration of cholesterol and the thermal conductivity of a model membrane. Our results suggest an increase in the membrane thermal conductivity upon increasing the... 

The long-term performance of LiFi networks significantly depends on the location of access points. The optimized placement can be determined based on the distribution of users in the room. In this paper, we investigate the placement optimization for average throughput maximization in the presence of asymmetric distributions. In particular, we represent users' distribution in the indoor environment by the Gaussian mixture model, which is powerful and computationally convenient. Then we obtain the optimized deployment for different scenarios using gradient ascent algorithm. The results show that optimization of deployment significantly improves the average throughput of the network. As the...