This Letter proposes generalized reaction–diffusion equations for treating noisy magnetic resonance images. An edge-enhancing functional is introduced for image enhancement. A number of super-diffusion operators are introduced for fast and effective smoothing. Statistical information is utilized for robust edge-stopping and diffusion-rate estimation. A quasi-interpolating wavelet algorithm is u...

Reaction-diffusion systems produce a variety of patterns such as spots, labyrinths, and rotating spirals. Circular spots may be stationary or unstable to oscillating motion. The oscillations are sometimes steady but may lead to collapsing or infinitely expanding spots. Using a singular perturbation technique we derive a set of ordinary differential equations for the dynamics of circular spots. ...

Leaching of molybdenite concentrate with hydrogen peroxide in sulfuric acid solution was investigated to determine the effects of reaction time, reaction temperature, H2O2 concentration, H2SO4 concentration, pulp density and rotation speed on molybdenum extraction and molybdenite dissolution kinetics, using the Taguchi method. From analysis of var...

We consider the numerical time integration of a class of reaction–transport systems that are described by a set of ordinary differential equations for primary variables. In the governing equations, the terms involved may require the knowledge of secondary variables, which are functions of the primary variables. Specifically, we consider the case where, given the primary variables, the evaluatio...

<p style='text-indent:20px;'>In this paper we analyse the asymptotic behaviour of some nonlocal diffusion problems with local reaction term in general metric measure spaces. We find certain classes nonlinear terms, including logistic type for which solutions are globally defined initial data Lebesgue prove satisfy maximum and comparison principles give sign conditions to ensure global bou...

Stochastic, spatial reaction-diffusion simulations have been widely used in systems biology and computational neuroscience. However, the increasing scale and complexity of models and morphologies have exceeded the capacity of any serial implementation. This led to the development of parallel solutions that benefit from the boost in performance of modern supercomputers. In this paper, we describ...

the kinetic of the heterogeneous chemical reaction of aluminum hydroxide and fluosilicic acid was studied. it was found that the diffusion of the reactants through the porous silica coating to the aluminum hydroxide surface and the interfacial chemical reaction between the diffusing reactant and aluminum hydroxide platelets control the overall reaction rate. these two phenomena were studied and...

This study presents the Homotopy Perturbation Method (HPM) for nonlinear fractional reaction diffusion systems, derivatives are described in caputo's' operator. The focus on three systems of equations one, two and dimensions, this method, solution considered as sum an infinite series. Which converges rapidly to exact solution. is no need use Adomian's polynomials calculate terms; we test propos...