it seems using the maxwell-stefan (m-s) diffusion model in combination with the vacancy solutiontheory (vst) and the single-component adsorption data provides a superior, qualitative, andquantitative prediction of diffusion in zeolites. in the m-s formulation, thermodynamic factor (г) isan essential parameter which must be estimated by an adsorption isotherm. researchers usually utilizethe simp...

It seems using the Maxwell-Stefan (M-S) diffusion model in combination with the vacancy solution theory (VST) and the single-component adsorption data provides a superior, qualitative, and quantitative prediction of diffusion in zeolites. In the M-S formulation, thermodynamic factor (Г) is an essential parameter which must be estimated by an adsorption isotherm. Researchers usually utilize the ...

A seminal milestone in lattice statistics is the exact solution of the enumeration of dimers on a simple-quartic net obtained by Fisher, Kasteleyn, and Temperley (FKT) in 1961. An outstanding related and yet unsolved problem is the enumeration of dimers on a net with vacant sites. Here we consider this vacant-site problem with a single vacancy occurring at certain specific sites on the boundary...

Free vibration characteristics of polymer composite plates reinforced by graphene nanosheets employing the Eringen nonlocal elasticity theory were investigated. Theoretical formulations are derived based on Hamilton’s principle implementing linear orthotropic constitutive equations of lamina while the behavior of nanostructure points affected by all other nonlocal points is also taken into acco...

The electronic properties of sphalerite (110) surface with Zn-vacancy and S-vacancy were calculated by using density-functional theory, and the effects of vacancy defect on the copper activation of sphalerite were investigated. The calculated results indicate that surface state occurs in the band gap of Zn-vacancy sphalerite, which is from the contribution of S 3p orbital at the first layer of ...

Oxygen vacancies in metal oxides are known to determine their chemistry and physics. The properties of neutral oxygen vacancies in metal oxides of increasing complexity (MgO, CaO, alpha-Al2O3, and ZnO) have been studied using density functional theory. Vacancy formation energies, vacancy-vacancy interaction, and the barriers for vacancy migration are determined and rationalized in terms of the ...

We develop a version of the vacancy mediated tracer diffusion model, which follows the properties of the physical system of In atoms diffusing within the top layer of Cu(0 0 1) terraces. This model differs from the classical tracer diffusion problem in that (i) the lattice is finite, (ii) the boundary is a trap for the vacancy, and (iii) the diffusion rate of the vacancy is different, in our ca...

Density functional theory is used to investigate vacancies at or below the ~111! surface of palladium and in the bulk. An accurate nonlocal pseudopotential for Pd based on relativistic all-electron calculations is employed. The interaction of the vacancy, a point defect, with a surface, a planar defect, is investigated. Also studied is the interaction between electronic structure and lattice st...