By changing the temperature, pH, stirring rate, or time for calcium carbonate crystallization, complex shapes of aggregated calcium carbonates formed. Such shapes have earlier been ascribed to specific interactions with specialized additives. Without polymeric additives, aggregates of vaterite transformed more rapidly into calcite aggregates under slow than under fast stirring. With an anionic ...

A method of visualizing and characterizing stirring structures of high Rayleigh number geophysical flows whose time dependence is strongly aperiodic is presented. To this end, the system is leaked by defining a smaller region of the flow, so that a particle is considered to be escaped if it enters this region. By means of an ensemble of nonescaped tracers, we are able to characterize stirring a...

during storage, serum separation is a major defect that affects the market share of doogh. therefore, in the present study the effects of high shear stirring and homogenization, as major operation units, on the stability was investigated. to do so, dooghs were stirred at various speeds and time scales (9000 rpm and 11000 rpm for 30 s and 2 min), homogenized at different pressures (0, 20, 50, 80...

a  facile  effective  stirring  aging  at  room  temperature  prior  to  conventional  hydrothermal treatment was employed in the template-free synthesis of micro- and nano-crystalline sodalites with  two  different  initial  gel  compositions.  the  effect  of  initial  si/al  molar  ratio,  naoh concentration and stirring aging time were investigated on the morphology and particle size of the...

The effect of stirring in an inhomogeneous oscillatory medium is investigated. We show that the stirring rate can control the macroscopic behavior of the system producing collective oscillations (synchronization) or complete quenching of the oscillations (oscillator death). We interpret the homogenization rate due to mixing as a measure of global coupling and compare the phase diagrams of stirr...

Stirring largely eliminated the greater effectiveness of Carbowax 6000 compared to mannitol in reducing cucumber (Cucumis sativus L.) hypocotyl section elongation. Stirring increased elongation in water but reduced elongation in growth regulator solution. Shrinkage of cells without plasmolysis in hypertonic Carbowax solutions indicates that Carbowax 6000 did not penetrate cell walls. Sections p...

In this paper a particle-base model is used to visualize results of the magnetohydrodynamics (MHD) phenomena related to electromagnetic levitation (EML) and magnetic stirring. Using the theoretical model presented in Part I, a numerical algorithm for fluid flow simulation has been described. To struggle out the local dynamics, the position and velocity of each particle is visualized and the int...

We prove the existence of invariant curves for a T – periodic Hamiltonian system which models a fluid stirring in a cylindrical tank, when T is small and the assigned stirring protocol is piecewise constant. Furthermore, using the Numerical Analysis of the Fundamental Frequency of Laskar, we investigate numerically the break down of invariant curves as T increases and we give a quantitative est...

a simple, rapid and efficient dispersive liquid–liquid microextraction by use of ionic liquid (il-dllme)method, followed by flame atomic absorption spectrometry (faas) was developed for the preconcentrationand determination of palladium in water samples. in this method, an appropriate mixture of acetone and octylmethyl imidazolium hexafluorophosphate was injected rapidly into the aqueous sample...