A = constant b = vortex spacing C = constant to adjust turbulent spreading q = rms turbulence velocity R = mean radius T = parameter for vortex age t = time u = axial velocity v = lateral velocity w = descent speed y = spanwise coordinate, positive for port vortex z = vertical coordinate, positive pointing upwards = circulation = eddy dissipation rate = standard deviation = (effective) kinemati...

Abstract The formation of dust ion-acoustic shocks (DIASs) in a four-component quantum plasma whose constituents are electrons, both positive and negative ions and immobile charged dust grains, is studied. The effects of both the dissipation due to kinematic viscosity and the dispersion caused by the charge separation as well as the quantum tunneling due to the Bohm potential are taken into acc...

On a daily basis we stir tee or coffee with spoon and leave it to rest. We know empirically the larger stickiness, viscosity, of fluid, more rapidly its velocity slows down. It is surprising, therefore, that variation, decay rate velocity, has not been utilized for measuring (kinematic) viscosity fluids. This study shows spectroscopy decomposing field into fluid modes (Stokes eigenmodes) allows...

Flowmetering terms can often seem cryptic. Here are definitions of some of the most commonly used. ACCURACY Accuracy is a quantity defining the limit that errors will not exceed. This value should include the combined effects of conformity, hysteresis, deadband, and repeatability errors. When applied to flowmeters, accuracy is specified in one of two different ways; % of full scale or % of rate...

We investigated the thermal diffusion behavior of aqueous solutions of monosaccharides with the infrared thermal diffusion forced Rayleigh scattering (IR-TDFRS) setup. As monosaccharides, we studied the three aldohexoses glucose, galactose, and mannose and the two ketohexoses sorbose and fructose. All sugars have the same molecular weight, but their structures differ as well as some physical pr...

The swimming behaviour of microorganisms can be strongly influenced by the rhe­ ology of their fluid environment. In this manuscript, we experimentally investigate the effects of shear-thinning viscosity on the swimming behaviour of an undula­ tory swimmer, the nematode Caenorhabditis elegans. Tracking methods are used to measure the swimmer’s kinematic data (including propulsion speed) and vel...

This research investigates how the properties of the Nigerian crude residue can be improved on to enhance its local usage. Chemical treatment was carried out on Nigerian crude residue and its rheological properties were tested. The physiochemical propertiesspecific gravity cum viscosity measured after the treatment gave 12.44% improvement in specific gravity and 17.92 times improvement in visco...

The quality of veterinary vaccines is monitored by physicochemical, microbiological and biological tests. Two of the most important physicochemical parameters are viscosity and density, which are determined in the three different types of matrices: emulsions, suspensions and solvents. Viscosity, known as internal friction or viscose medium, is a feature of fluids and plastic solids characterize...

to examine hydraulics of lnapls in soil, the retention curves of diesel fuel and water were both determined by hanging column method. the soil retention parameters were obtained based on van genuchten, brooks-corey and campbell’s models. in addition, the soil hydraulic conductivity for both fluids were predicted based on mualem- brooks-corey, burdine- brooks-corey, mualem-van genuchten and camp...

due to the high price of virgin vegetable oils and the drawbacks of the homogeneous catalytic transesterification, in this work an economically profitable alternative process was proposed for biodiesel synthesis in which transesterification of the low-cost waste cooking oil (wco) with methanol in a heterogeneous system was done. alumina impregnated with sodium hydroxide was utilized as a solid ...