in the present study, the production of dextran from date extract and sucrose as carbon sources by the bacterium leuconostoc mesenteroides nrrl b512 (f) was investigated. in comparison to blue dextran (mw≈2000 da), dextran molecular weight was reduced (mw2000 kda). flow behavior indices of dextran solutions from date extracts were investigated and rheological parameters were evaluated at concen...

natural vibration analysis of plates represents an important issue in engineering applications. in this paper, a new and simplify method for vibration analysis of circular and rectangular plates is presented. the design of an effective robust controller, which consistently attenuates transverse vibration of the plate caused by an external disturbance force, is given. the dynamics of the plate i...

As the stress amplitude in anchorage zone of cable-stayed bridges vary considerably, it is essential to study fatigue-load-bearing capacity structures cable-stayed-bridge girders. In this study, mechanical properties and force-transmission mechanism a built-in double-fixed steel anchor box, as well influence geometric design parameters main pressure plates support on its performance, were studi...

In the present study, the production of dextran from date extract and sucrose as carbon sources by the bacterium Leuconostoc mesenteroides NRRL B512 (f) was investigated. In comparison to blue dextran (Mw≈2000 Da), dextran molecular weight was reduced (Mw2000 KDa). Flow behavior indices of dextran solutions from date extracts were investigated and rheological parameters were evaluated at concen...

In this paper, a hybrid structural finite element (FE) acoustic wave based (WB) approach is formulated to avoid using extra acoustic FE in the case of a simple structural geometry but with complicated structural material properties. Following the formulation, the approach is implemented and validated. First, linear hexahedral solid elements with a selective reduced integration are implemented i...

Asymmetrical shear rolling with velocity asymmetry and geometry asymmetry is beneficial to enlarge deformation and refine grain size at the center of the thick plate compared to conventional symmetrical rolling. Dynamic recrystallization (DRX) plays a vital role in grain refinement during hot deformation. Finite element models (FEM) coupled with microstructure evolution models and cellular auto...

Based on results from computational studies and plate casting trials, deficiencies in the steel casting feeding rules as currently published by the Steel Founders’ Society of America (SFSA) were determined. A methodology for the development of improved steel casting feeding rules was established based on the Niyama criterion determined from simulation. Newly developed feeding rules using this m...

This study shows a thick plate, pointed on both sides, of variable elongation under action subsonic and supersonic air flows. The relevance the work is driven by development new aircraft that change their geometry during flight, in particular, relative flight. aim this to determine aerodynamic fields around taking into account its elongation, effect drag coefficient plate. Numerical simulation ...

Subducted sediments are thought to lubricate the subduction interface and promote faster plate speeds. However, global observations not clear-cut on relationship between amount of motion. Sediments also influence slab dip, but variations in geometry depend multiple factors. Here we use 2D thermomechanical models explore how can dynamics geometry. We find that thick lead slower due an increase m...

In this paper, the entropy generation minimization (EGM) method is applied to an industrial heat transfer problem: the forced convective cooling of a LED-based spotlight. The design specification calls for eighteen diodes arranged on a circular copper plate of 35 mm diameter. Every diode dissipates 3 W and the maximum allowed temperature of the plate is 80 °C. The cooling relies on the forced c...