Analysis of solid-solid reaction controlled by unidirectional diffusion.

Synthesis & Characterization of CaB4O7 Powder by Solid-State Reaction

The synthesis of calcium tetraborate was investigated in a temperature ranging from 800℃ to 900℃ using the solid-state reaction method. The synthesis was done using ammonium tetraborate tetrahydrate as the source of boron. At temperatures of 800 ℃ and 880 ℃, the mixed phases from different compounds were formed. At the optimum temperature of 840℃, the mixed phase was only composed of meta and t...

Travelling Waves for Solid-gas Reaction-diffusion Systems

We study a two-species reaction-diffusion problem described by a system consisting of a semilinear parabolic equation and a first order ordinary differential equation, endowed with suitable conditions. We prove the existing of a unique traveling wave profile and give necessary conditions and sufficient conditions for the occurrence of penetration and conversion fronts.

Kinetic model for solid diffusion with a competing surface reaction

where 8, is the thickness of diffusant initially plated on the surface of the specimen, D is the diffusivity, and c(x, t) is atomic fraction of the diffusant at (x, t). This expression is appropriate if the diffusion anneal is long compared to mSo2/4Dc'„ where c, is the solubility of the diffusant. "' In some systems, this condition cannot be met. For example, in the study of the diffusion of z...

Synthesis and Processing of SnO2, CaSnO3 and Ca2SnO4 Nanopowders by Solid-State Reaction Technique

The nanopowders of SnO2, CaSnO3 and Ca2SnO4 in the size rang of 5-70 nm have been prepared using solid-state reaction technique. The technique is convenient and inexpensive in comparison to the conventional routes of compound prepared and processing where, many steps of mixing and annealing are i...

Mathematical Modeling of Fluorination Reaction of Uranium Dioxide and Evaluation of Existing Gas-Solid Reaction Models