Flotation process in mechanical cells is carried out in highly turbulent conditions. In this work, the impact of impeller speed on four characteristics of the quiescent zone, i.e. zone height, turbulence, solid percentage, and gas holdup, and their relationship with the entrainment is investigated, and it is shown why at a higher impeller speed, entrainment is not significant. The height of the...

Several bulk model–based entrainment parameterizations for the atmospheric convective boundary layer (CBL) with wind shear are reviewed and tested against large-eddy simulation (LES) data to evaluate their ability to model one of the basic integral parameters of convective entrainment—the entrainment flux ratio. Test results indicate that many of these parameterizations fail to correctly reprod...

[1] The ‘‘transition zone water filter’’ (Bercovici and Karato, 2003) model relies on the presence of a dense hydrous melt above the 410-km discontinuity that is formed by dehydration melting as wet wadsleyite undergoes a phase change to low-water-solubility olivine. Recent studies suggest that, particularly in the Pacific, there is sufficient water in the transition zone for dehydration meltin...

The reported study examines the dynamics of entrainment and its effects on the evolution of the dry atmospheric convective boundary layer (CBL) when wind shear is present. The sheared CBL can be studied by means of direct measurements in the atmosphere, laboratory studies, and numerical techniques. The advantages and disadvantages of each technique are discussed in the present paper, which also...

The thickness of the entrainment zone at the top of the atmospheric mixed layer is analyzed using measurements made with a ground-based lidar during the BLX-83 and CIRCE field programs. When the entrainment-zone depth normalized by mixed-layer depth is plotted as a function of the entrainment rate normalized by the convective velocity scale, with time as a parameter, a hysteresis curve results....

BACKGROUND The efficacy of drugs used to treat inducible monomorphic sustained ventricular tachycardia (VT) has been assessed by investigating their ability to suppress inducibility, but the mechanism of the drug action remains to be determined. OBJECTIVES To determine electrophysiological variables that predict inducibility, divided doses of class I antiarrhythmic drugs were given and their ...

Entrainment of air by turbulent mixing plays a central role in the dynamics of eruption clouds; the amount of entrained air controls eruption styles and heights of eruption columns. The efficiency of entrainment is quantified by the entrainment coefficient: the ratio between mean inward radial velocity at the edge and the mean vertical velocity. We directly determined the entrainment coefficien...

A set of first-order model (FOM) equations, describing the sheared convective boundary layer (CBL) evolution, is derived. The model output is compared with predictions of the zero-order bulk model (ZOM) for the same CBL type. Large eddy simulation (LES) data are employed to test both models. The results show an advantage of the FOM over the ZOM in the prediction of entrainment, but in many CBL ...

In addition to being endogenous, a circadian system must be able to communicate with the outside world and align its rhythmicity to the environment. As a result of such alignment, external Zeitgebers can entrain the circadian system. Entrainment expresses itself in coinciding periods of the circadian oscillator and the Zeitgeber and a stationary phase difference between them. The range of perio...