Diffusion Laws and Modified Pascal’s Triangles

Abstract

Four main diffusion laws: 1D diffusion in a planar bulk sample or random walks along a straight line x=α1t1/2; 3D diffusion or random walks from a point source and forming small spherical particle: x=α2t1/3; 1D+1D diffusion or random walks along a straight plane with simultaneous outflow into balk: x=α3t1/4; 1D+2D diffusion or random walks along a straight line with simultaneous outflow into balk: x=α4t1/6 are analysed theoretically using mathematical modelling and appropriate physical models. Convex shape of the diffusion profile near the top along a dislocation pipe with simultaneous outflow into balk is predicted. It is shown that the cone angle near the top is increasing with time. Literature experimental data are used for analysis.

Copper and Aluminium Electrochemical Corrosion Investigation during Electrolysis and Heating from 20oC to 180oC

“…Diffusion kinetics in solid state are different in planar, cylindrical, and spherical samples [15], so we planned to analyse the electrochemical degradation of cylindrical and spherical copper (Cu) and aluminium (Al) anodes in an electrolyte (concentrated aqueous NaCl solution) under different temperature conditions.…”