Effects of binary chemical reaction and Arrhenius activation energy in Darcy–Forchheimer three-dimensional flow of nanofluid subject to rotating frame

Darcy–Forchheimer three-dimensional rotating flow of nanoliquid in the presence of activation energy and heat generation/absorption is examined. Heat and mass transport via convective process is considered. Buongiorno model has been employed to illustrate thermophoresis and Brownian diffusion effects. Adequate transformation procedure gives rise to system in terms of nonlinear ODE’s. An efficient numerical technique namely NDsolve is used to tackle the governing nonlinear system. The graphical illustrations examine the outcomes of various sundry variables. Heat and mass transfer rates are also computed and examined. Our results indicate that the temperature and concentration distributions are enhanced for larger values of porosity parameter and Forchheimer number.

     

Ergodic stationary distribution and practical application of a hybrid stochastic cholera transmission model with waning vaccine-induced immunity under nonlinear regime switching

Considering the effect of stochasticity including white noise and colored noise, this paper aims to study a hybrid stochastic cholera epidemic model with waning vaccine-induced immunity and nonlinear telegraph perturbations. First, we derive a critical value ${?}_0^C$ related to the basic reproduction number ${?}_0$ of the deterministic model. The key aim of this paper is to generalize the θ-stochastic criterion method proposed by the recent work (Han et al. in Chaos Solit Fract 140:110238, 2020) to eliminate nonlinear telegraph perturbations. Next, via constructing several θ-stochastic Lyapunov functions and using the generalized method, we further prove that the stochastic model have a unique ergodic stationary distribution under ${?}_0^C>1$. Results show that the prevention and control of cholera epidemic depend on low transmission rate and small telegraph perturbations. Finally, the corresponding numerical simulations are performed to illustrate our analytical results and a practical application on the Somalia cholera outbreak is shown at the end of this paper.     

Nanocomposites of polyaniline functionalized graphene oxide: synthesis and application as a novel platform for removal of Cd(II), Eu(III), Th(IV) and U(VI) in water

The characterization of the nanocomposites (PANI@GO) by SEM, TEM, Raman and FT-IR indicated that the GO has been functionalized via PANI successfully. PANI@GO as a novel platform for the removal of Cd(II), Eu(III), Th(IV) and U(VI) from aqueous solutions, the uptake process was a spontaneous endothermic process, and is strongly dependent of pH but independent of ionic strength. The adsorption kinetic and isotherm were fitted well the Pseudo-second-order equation and Langmuir model. PANI@GO were recycled and re-used without significant loss of adsorption capacity, and real samples were also treated which showed that had little interference with the performance of it.     

Synthesis of ordered mesoporous carbonaceous materials and their highly efficient capture of uranium from solutions

An extremely effortless method was applied for successful synthesis of mesoporous carbonaceous materials(MCMs) using well-ordered mesoporous silica as template. Various characterizations(scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR), Raman, X-ray photoelectron spectroscopy(XPS), Brunner-Emmet-Teller(BET) and Zeta potential) confirmed that MCMs had large surface area, uniform pore size distribution, and abundant oxygen-containing functional groups. The batch techniques were employed to study U(VI) adsorption on MCMs under a wide range of experiment conditions. The adsorption kinetics of U(VI) onto MCMs were well-fitted by pseudo-second-order kinetic model, indicating a chemisorption process. The excellent adsorption capacity of MCMs calculated from the Langmuir model was 293.95 mg g~(-1) at pH 4.0. The FT-IR and XPS analyses further evidenced that the binding of U(VI) onto MCMs was ascribed to the plentiful adsorption sites(–OH and –COOH groups) in the internal mesoporous structure, which could efficiently trap guest U(VI) ions. The results presented herein revealed that MCMs were ideal adsorbents in the efficient elimination of uranium or other lanthanides/actinides from aqueous solutions, which would play an important role in environmental pollution management application.     

Cavity QED based tuneable,delayed-choice quantum eraser

We propose an experimentally feasible idea for the delayed-choice quantum eraser, having adjustable path distinguishability/fringe visibility. The schematics are based on resonant, dispersive and Ramsey interactions of atoms under cavity QED scenario. The option for tuneability of the fringes in a delayed-choice setup stringently marks the conception of the time in the quantum theory, operational meanings of the state vector reduction and raises questions about Ψ$\Psi$-ontic models while helping to shed out the controversies surrounding the quantum eraser theme. The proposal can be efficiently executed experimentally within the prevailing cavity QED experimental research scenario with good overall success probability and fidelity.     

Nonlinear measure approach for the robust exponential stability analysis of interval inertial Cohen–Grossberg neural networks

This article is concerned with the existence and robust stability of an equilibrium point that related to interval inertial Cohen–Grossberg neural networks. Such condition requires the existence of an equilibrium point to a given system, so the existence and uniqueness of the equilibrium point are emerged via nonlinear measure method. Furthermore, with the help of Halanay inequality lemma, differential mean value theorem as well as inequality technique, several sufficient criteria are derived to ascertain the robust stability of the equilibrium point for the addressed system. The results obtained in this article will be shown to be new and they can be considered alternative results to previously results. Finally, the effectiveness and computational issues of the two models for the analysis are discussed by two examples. © 2016 Wiley Periodicals, Inc. Complexity 21: 459–469, 2016     

Dynamical analysis of a delayed six‐neuron BAM network

In this article, a simplified bidirectional associative memory network with delays involving six neurons is considered. By analyzing the distribution of roots of the characteristic equation for linearized system regarding the sum of delay as a bifurcation parameter, we obtain the condition of the occurrence for Hopf bifurcation. It reveals that Hopf bifurcation occurs when the sum of the delay passes through a critical value. The direction and the stability of the bifurcating periodic solution are determined by applying the normal form theory and center manifold theorem. Finally, a numerical example is used to illustrate the validity of theoretical results obtained. © 2015 Wiley Periodicals, Inc. Complexity 21: 9–28, 2016     

Field of a Point Source Within Perfectly Conducting Parallel-Plates in a Homogeneous Biisotropic Medium

The spherical wave scattering response by a perfectly conducting open–ended waveguide in a biisotropic medium is obtained. Interestingly, the vector diffraction problem is reduced to the scattering of a single scalar field, this scalar field being the normal component of either a left–handed or a right–handed Beltrami field. Here, we explicitly consider the scattering of the left–handed field component, that of the other scalar field being analogously tractable. The solution is constructed with the aid of the Wiener–Hopf technique.     

Peristaltic flow of a Maxwell fluid in a channel with compliant walls

This paper describes the peristaltic motion of a non-Newtonian fluid in a channel having compliant boundaries. Constitutive equations for a Maxwell fluid have been used. Perturbation method has been used for the analytic solution. The influence of pertinent parameters is analyzed. Comparison of the present analysis of Maxwell fluid is made with the existing results of viscous fluid.