Diffusion is the omnipresent, random motion of matter, such as atoms and molecules, driven by thermal energy and is the key for innumerable processes in nature and technology. In nearly every chemical reaction diffusion is the key mechanism of bringing the reactants in close proximity, which is an essential prerequisite before any reaction can take place. Additionally many reactions are diffusi...

Diffusion and reaction in heterogeneous media arise in a host of phenomena in the physical and biological sciences. The determination of the mean survival time z (i.e., inverse trapping rate) and relaxation times T,, n = 1, 2, 3 .... (i.e., inverse eigenvalues), associated with diffusion among partially absorbing, static traps with surface rate constant K are problems of long-standing interest....

an analytical study was performed to study effects of thermo-diffusion and chemical reactions on a three-dimensional mhd mixed convective flow of dissipative fluid along an infinite vertical porous plate with transverse sinusoidal suction velocity. the parabolic partial differential equations governing the fluid flow, heat transfer, and mass transfer were solved using perturbation technique and...

in the present study, a new gas diffusion electrode (gde) (based on pt/nafion membrane) is fabricated. the electrochemical results show that the new gde has the highest electrochemical activity toward the oxygen reduction reaction (orr) among the three electrodes. the sem and xrd findings show that a platinum layer can be attached to nafion membrane closely and firmly with a strong peak corresp...

Introduction: Fabrication of hybrid skeletal tissue constructs often involves creation of a mineralized component, mimicking bone and the interface between soft tissue and bone. One of the key structural components of the interface to bone, and bone itself, is hydroxyapatite. Hydroxyapatite can be formed rapidly in vitro by controlled reaction of calcium (Ca) and phosphate (PO4) with the use of...