An experimental study has been carried out to characterize bubble formation, growth, and detachment mechanisms in a stagnant liquid column. Both bubble frequency and bubble detachment size were measured in different gas flow rates, injector diameters and orientations, submergence height, and liquid properties. Experiments were performed for air injection flow rate ranges between 200 mlph and 12...

in this research, the effect of bubble surface area flux, sb, and particle size on flotation rate constant, k, of pyrite (fes2) particles was studied using bubble-particle interactions. the bubble-particle collision, attachment and detachment efficiencies were calculated under different flow regimes. the k increased with increase in the collision efficiency and decrease in the detachment effici...

We study a model of interfacial crack in which contact of the crack faces obeys a Coulomb law of friction. For such cracks, the possibility that the stress has a stronger singularity than rÿ1=2 near the tip has been reported. In this paper, we demonstrate that these strong singularities can, in fact, be discarded, because they would assume a backward propagation of the crack. In passing, we pro...

In this research, the effect of bubble surface area flux, Sb, and particle size on flotation rate constant, k, of pyrite (FeS2) particles was studied using bubble-particle interactions. The bubble-particle collision, attachment and detachment efficiencies were calculated under different flow regimes. The k increased with increase in the collision efficiency and decreas...

Multi-subunit RNA polymerases bind nucleotide triphosphate (NTP) substrates in the pretranslocated state and carry the dNMP-NTP base pair into the active site for phosphoryl transfer. NTP-driven translocation requires that NTP substrates enter the main-enzyme channel before loading into the active site. Based on this model, a new view of fidelity and efficiency of RNA synthesis is proposed. The...

Flow separation and vortex shedding are some of the most common phenomena experienced by bluff bodies under relative motion with the surrounding medium. They often result in a recirculation bubble in regions with adverse pressure gradient, which typically reduces efficiency in vehicles and increases loading on structures. Here, the ability of an engineered coating to manipulate the large-scale ...

In recent years, there has been a growing interest in bioreactors, which utilise immobilised enzymes and cells in order to improve the bioprocess productivity. In fact, there are many specific advantages of the immobilised systems in comparison with the more conventional systems, in which the bio-agents are suspended freely (cells) or dissolved in a bulk aqueous medium (enzymes): • high cell de...