With porosity decreasing under the compression, the effective diffusion coefficient decreased faster in the through-plane direction than in the in-plane direction; the formula derived by Nam and Kaviany was capable of describing the change of the effective diffusion coefficient with porosity in the in...
The expressions for effective diffusion coefficient are obtained in the mean field approximation for two-phase system for spatial dimensions of 1, 2 and 3. The existence of potential barrier for diffusion on the phase boundary was taken into account via the boundary conditions. Obtained formulae co...
6) gas effective diffusion coefficient 气体有效扩散系数 1. On the basis of studying gas transfers mechanism into porous medium materials,a calculation formula ofgas effective diffusion coefficientof concrete based on pressure gradient is deduced according to the relative theory,and a new rapid testing...
We consider the problem of determining analytically the effective diffusion constant Deff for diffusion in an inhomogeneous medium, described by the diffusion equation deltatP = deltax[D(x) delta xP] with a position-dependent diffusion coefficient D(x). As there is no translational invariance, two...
1-dim. diffusion D1 1/2α α2 2-dim. diffusion D2 –[1/ln(1 –α)] α + (1 –α) ln (1 –α) 3-dim. diffusion D3 (3/2)(1 –α)2/3/[(1 –α)−1/3 – 1] [1 – (1 –α)1/3]2 (Jander) 3-dim. diffusion D4 (3/2)/[(1 –α)−1/3 -1] 1– ...
The formula for the equation is as follows: Kp is the intraparticle diffusion rate constant, 't' denotes the agitation time in minutes, 'α' denotes the initial adsorption rate (mg/g min), and 'β' represents the desorption constant grams per milligram during any given experiment. The ...
The Knudsen diffusion is accurately captured by a local diffusion coefficient computed based on a corrected Bosanquet-type formula with the local pore size determined by the largest sphere method. A robust validation of the new framework is demonstrated by predicting the effective gas diffusion ...
Also, tortuosity can be seen as a more intuitive quantity for fluid flow and transport through a pore geometry than permeability or the effective diffusion coefficient. The outline of this work is as follows: first we will conduct a literature review on the methods commonly used to compute the...
Malachite green (MG) dye was purchased from CH Chemajet, Egypt, with molecular formula C23H25N2Cl and molecular weight of 364.92 g/mol with λmax = 615 nm. Methods Preparation of pectin-grafted poly(acrylamide-co-sodium acrylate) hydrogel Pcn-g-P(Am-co-SA) hydrogel was synthesized by...
(ICDD card No. 48-1023 and ICDD card No. 51-1525). Moreover, for the highest peak intensity at 2θ = 11.63°, the basal spacing is 7.60 Å. The crystalline size of Zn–Mg–Al/LDH was calculated using Deby-Sherrer's formula and found to be 3.60 nm, which is within the ...