the effect of mechanical activation on structural changes and kinetics of carbothermic reduction of hematite with graphite was studied in this research. hematite powder mixture with graphite (with stoichiometry ratio c/o=1) was milled for the time periods of zero to 50 hours, and the structural changes were studied using x ray diffraction (xrd). the effect of mechanical activation on the kineti...

in this study at first , an azo dye, 2,7- naphthalenediol, 2-[(4-bromophenyl)azo (bpand) as a ligand has been synthesized by addition of p-bromoaniline to the modified montomorillonite k10 clay. this ligand was characterized using 1h-nmr, uv-vis and ir spectroscopies. subsequently, its interaction with calf thymus deoxyribonucleicacid ,ct-dna was investigated in 5 mm phosphate buffer solution, ...

In this paper, mixed convection of Al2O3-EG-Water nanofluid in a square lid-driven enclosure is investigated numerically. The focus of this study is on the effects of variable thermophysical properties of the nanofluid on the heat transfer characteristics. The top moving and the bottom stationary horizontal walls are insulated, while the vertical walls are kept at different constant temperature...

springs are the  mechanical parts which have many application in industries. static and dynamic forces cause relaxation in these parts so that they lose some of their free length and reaction force. springs constant are very important in airplane and vailway industry since constant and variable forces are applied to them in period time, therefore it is necessary to avoid decreasing in spring co...

We investigate the characteristics of constant-amplitude input shapers for robust time-optimal maneuvers of exi-ble structures. Trends in the timing of the shaper impulses are shown as a function of the system damping constant and move distance. The insensitivity to modeling errors, time-optimality, amount of vibration caused during maneuvers, and high frequency excitation of these shapers are ...