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91.
It is shown that sum of information entropies in position and momentum space, quantifies the temporal information in wave packet dynamics of a dynamical system. Quantum fractional revivals are investigated on these bases in periodically driven Fermi-Ulam accelerator. It is observed that the entropic measure provides deeper insight of the wave packet dynamics for the long time evolution as compared with conventional autocorrelation function. It is shown that these revival times are not symmetric in driven situations and may lead to a random behavior. 相似文献
92.
This article investigates the effects of an induced magnetic field on the mixed convection peristaltic motion of nanofluid in a vertical channel. Transport equations involve the combined effects of Brownian motion and thermophoretic diffusion of nanoparticles. Analysis has been addressed subject to long wavelength and low Reynolds number assumptions. Explicit expressions of stream function, magnetic force function, temperature and nanoparticles concentration are developed. Analytic expressions are validated with the obtained numerical solutions. Peristaltic pumping rate is found to increase upon increasing the strengths of electric and magnetic fields and the buoyancy force due to temperature gradient. Moreover temperature rises and nanoparticles concentration decreases with an intensification in the Brownian motion effect. 相似文献
93.
We explain quantum revivals and fractional revivals in phase space of the Fermi?CUlam accelerator. We derive analytic expressions of the Wigner distribution function for the driven system describing quantum interferences in position and momentum space. We assume that the fractional revival times are nonrecurrent under certain conditions and display randomness in the occurrence of the phenomenon at these times. 相似文献
94.
Okadaic acid (OA), a lipophilic phycotoxin is mainly produced by toxigenic dinoflagellates. The need to develop high performing methods for OA analysis able to improve the traditional ones is evident. In this work, a novel experimental methodology for label-free detection of OA was developed. Protein G magnetic beads (protein-G-MBs) modified gold electrode was used to immobilize anti-OA monoclonal antibody (anti-OA-MAb). Preliminary, colorimetric tests were performed in order to validate protein-G-MBs and anti-OA-MAb reaction. Electrochemical detection was carried out by differential pulse voltammetry in ferri/ferrocyanide solution. The limit of detection value obtained (0.5 μg L−1) validated the developed electrochemical immunosensor as a promising tool for routine use. The matrix effect and the recovery rate were also assessed with real samples, showing a good percentage of recovery. 相似文献
95.
T. Hayat M. Awais S. Obaidat 《Communications in Nonlinear Science & Numerical Simulation》2012,17(2):699-707
This investigation reports the three-dimensional flow of Jeffrey fluid over a linearly stretching surface. Transformation method has been utilized for the reduction of partial differential equations into the ordinary differential equations. The solutions of the nonlinear systems are presented by a homotopy analysis method (HAM). The reported graphical results are analyzed. A comparative study with the previous results of viscous fluid in the literature is made. 相似文献
96.
S.Nadeem Anwar Hussain M.Y.Malik T.Hayat 《应用数学和力学(英文版)》2009,30(10):1255-1262
This study derives the analytic solutions of boundary layer flows bounded by a shrinking sheet. With the similarity transformations, the partial differential equations are reduced into the ordinary differential equations which are then solved by the homotopy analysis method (HAM). Two-dimensional and axisymmetric shrinking flow cases are discussed. 相似文献
97.
Mechanics of Composite Materials - The fatigue life of megawatt-scale composite wind turbine blades implemented with shallow-angled laminates is investigated. Full dynamic simulations of a 5-MW... 相似文献
98.
Under a nonparametric robust regression model, we consider the problem of estimating the score function for a fixed x in a functional space and with unknown scale parameter. The principal aim of this work is to establish the asymptotic normality of this estimator for a stationary ergodic process without any use of traditional mixing conditions. 相似文献
99.
Zhou Baoquan Han Bingtao Jiang Daqing Hayat Tasawar Alsaedi Ahmed 《Nonlinear dynamics》2022,107(4):3863-3886
Nonlinear Dynamics - Recently, the stochastic $$\theta $$ -threshold method has been proposed to analyze the impact of second-order perturbations on disease persistence. In this paper, considering... 相似文献
100.
Imtiaz Maria Shahid Fiza Hayat Tasawar Alsaedi Ahmed 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2461-2470
Journal of Thermal Analysis and Calorimetry - The present paper explores non-Fourier heat flux theory for Jeffrey fluid flow subject to a rotating disk. The current analysis is executed in the... 相似文献