e consider the effects of adding a PIB-PDMS diblock copolymer as a compatibilizer in model lends composed of polyisobutylene PIB and polydimethylsiloxane PDMS . The ratio of PIB to DMS was varied from 20:80 to 80:20 and, hence, these blends are dubbed “concentrated” blends. ost experiments were conducted on blends containing 0.01 or 0.1 wt. % compatibilizer. All lends had a droplet-matrix morph...

We calculate the shear viscosity of field theories with gravity duals of Gauss-Bonnet gravity with a non-trivial dilaton using AdS/CFT. We find that the dilaton filed has a non-trivial contribution to the ratio of shear viscosity over entropy density and after imposing causal constraint for the boundary field theory, the new lower bound 4/25π, obtained from pure Gauss-Bonnet gravity, may have a...

[1] The microstructure of partially molten rocks plays a key role in determining their physical properties. The area fraction of intergranular contact, contiguity, governs the establishment of a skeletal framework of solid grains and controls the effective elastic moduli of the aggregate. This work presents a theoretical calculation of steady state grain shape, contiguity, effective elastic mod...

Viscosity has been determined during isothermal crystallization of an andesite from Tungurahua volcano (Ecuador). Viscosity was continuously recorded using the concentric cylinder method and employing a Pt-sheathed alumina spindle at 1 bar and from 1400°C to subliquidus temperatures to track rheological changes during crystallization. The disposable spindle was not extracted from the sample but...

Hydrate plugging is the major challenge in the flow assurance of deep-sea pipelines. For water-in-oil emulsions, this risk could be significantly reduced with the addition of anti-agglomerants (AAs). Hydrates often form from water-in-oil emulsions and the measurement of emulsion and slurry viscosity constitutes the basis for the application of hydrate slurry flow technology. In this work, using...

In this research, biodiesel was produced using chicken fat in the presence of calcium oxide nano-catalyst. To do so, the effect of various parameters like temperature, reaction time, catalyst amount and methanol to oil ratio was investigated on the biodiesel production. The results showed that the best conditions for biodiesel production were obtained such as the temperature of 65oC, methanol t...

Three dimensional flow of non-Newtonian viscoelastic fluid with the variation in the viscosity over a stretching surface is investigated. The governing partial differential equations of continuity, momemtum, energy and concentration are transformed into nonlinear ordinary differential equations by using similarity transformations. The transformed equations are solved numerically by fourth-order...

Transport coefficients of gluon plasma are calculated for a SU(3) pure gauge model by lattice QCD simulations on 163×8 and 243×8 lattices. Simulations are carried out at a slightly above the deconfinement transition temperature Tc, where a new state of matter is currently being pursued in RHIC experiments. Our results show that the ratio of the shear viscosity to the entropy is less than one an...

We use the real-time finite-temperature AdS/CFT correspondence to compute the effect of general R corrections to the gravitational action in AdS space on the shear viscosity of the dual gauge theory. The R terms in AdS5 are determined by the central charges of the CFT. We present an example of a four-dimensional gauge theory in which the conjectured lower bound of 1/4π on the viscosity-to-entro...

nowdays, production of high quality engine oils is one of the worries of our country’s engine oil industry. in this study, the behavior of four commercial polymers used in nation motor oil industry in obtaining the best viscosity index improver was investigated. in this regard, viscometric behavior, shear stability and polymers’ performance for engine cranking were compared at low temperature. ...