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...

This paper investigates the effect of inserting a ring type barrier on leakage flow of brush seals with different bristles clearances (the distance between bristle pack tip and rotor surface). The ring is placed on both upstream and downstream sides of the bristles. An axisymmetric CFD model is employed to calculate radial pressure distribution along backing plate, axial pressure variation on r...

Rotational constraint representing a local external bias generally has a nontrivial effect on the critical behavior of lattice statistical models in equilibrium critical phenomena. In order to study the effect of rotational bias in an out-of-equilibrium situation like self-organized criticality, a two state "quasideterministic" rotational sandpile model is developed here imposing rotational con...

Abstract. We study equilibrium states of the Smoluchowski equation for rigid, rod-like polymer ensembles. We start with several cases in the three dimensional space: a) nematic polymers where the only intermolecular interaction is the excluded volume effect, modeled using the Maier-Saupe potential, b) dipolar nematic polymers where the intermolecular interaction consists of the dipoledipole pot...

A theoretical solution is presented for the forced convection heat transfer of a viscoelastic fluid obeying the Giesekus constitutive equation in a concentric annulus under steady state, laminar, and purely tangential flow. A relative rotational motion exists between the inner and the outer cylinders, which induces the flow. A constant temperature was set in both cylinders, in this study. The f...

Wehave constructed an optical centrifugewith a pulse energy that is more than 2 orders of magnitude larger than previously reported instruments. This high pulse energy enables us to create large enough number densities of molecules in extreme rotational states to perform high-resolution state-resolved transient IR absorption measurements. Here we report the first studies of energy transfer dyna...

Herein, hydrodynamic analysis from a large-eddy simulation in Couette–Taylor–Poiseuille (CTP) geometry is numerically investigated. The present inspired by previous experimental work which heat transport phenomena were investigated recovery system devoted to rotary kiln facility. streamwise and spanwise components of the velocity Reynolds stress tensor are firstly validated using an benchmark. ...

We demonstrate a cylindrical rotating triboelectric nanogenerator (TENG) based on sliding electrification for harvesting mechanical energy from rotational motion. The rotating TENG is based on a core-shell structure that is made of distinctly different triboelectric materials with alternative strip structures on the surface. The charge transfer is strengthened with the formation of polymer nano...

Rotational movements in the territory of vertebrobasilar artery of the head and neck can induce vertebrobasilar insufficiency (VBI) or infarction. The term "bow hunter's stroke" or "rotational VBI" has been used to describe this clinical syndrome. In most cases, symptoms were provoked because of involvement of a dominant vertebral artery (VA) with hypoplasia or occlusion of the contralateral VA...