In this paper we derive two rigorous properties of residence-time distributions for flows in pipes and mixers motivated by computational results of Khakhar et al. [Chem. Eng. Sci. 42, 2909 (1987)], using some concepts from ergodic theory. First, a curious similarity between the isoresidence-time plots and Poincare maps of the flow observed in Khakhar et al. is resolved. It is shown that in long...

A model potential for two-particle relativistic systems is investigated in the framework of Poincare-invariant quantum mechanics (or relativistic Hamiltonian dynamics). The potential considered allows to reduce the main integro-differential equation of Poincare-invariant quantum mechanics to the equation analogous to the radial equation and have analytical solution for relativistic bound system...

a gel composite (based on polyacrylamide and crosslinker cr(iii) acetate) was prepared by solvent method (distillate and water formation) and nanoclay particle (kaolinite). using xrd tests, d001 was evaluated for kaolinite nanoparticles in gel composite. kaolinite modification using dimethyl-sulfoxide led to increase interlamellar spacing from 7.21 to 10.82 o a. based on the results obtained fo...

We describe how to determine transfers between libration point orbits and either the surface of the Moon or a Low Earth Orbit within the Circular Restricted Three – Body Problem (CR3BP) assumptions. Moreover, we explain how to refine such trajectories to ones verifing more comprehensive equations of motion. We are interested in seeing how the geometry of the nominal target orbits and of the ass...

Heart Rate Variability (HRV) is the measure of time difference between two successive heart beats and its variation occurring due to internal and external stimulation causes. HRV is a non-invasive tool for indirect investigation of both cardiac and autonomic system function in both healthy and diseased condition. It has been speculated that HRV analysis by nonlinear method might bring potential...

The smart OGY control method is proposed for two-link rigid robot arm. For this goal the Bifurcation diagram should be applied for acceptable wide range of the input amplitude. Then by using the robot arm in a chaotic amplitude range and Poincare section, the UPO's will be found. After that, the OGY rules are defined for each UPO's and the maximum changed value of amplitude for each UPO's, whic...