A microscopic statistical model of a quantum solid is developed, where inside crystalline lattice there can exist regions disorder, such as dislocation networks or grain boundaries. The cores these disorder are allowed for exhibiting fluid-like properties. If the composed Bose atoms, then aggregations exhibit Bose-Einstein condensation and hence superfluidity. randomly distributed throughout sa...

the michelsen stability and multiphase flash calculation by direct minimization of gibbs free energy of the system at constant temperature and pressure, was used for systems containing gas hydrates. the solid hydrate phase was treated as a solid solution. the fugacities of all components of the hydrate phase were calculated as a function of compositions by the rearranged model of van der waals ...

An internal ballistics model has been developed for performance prediction of a solid propellant rocket motor. In this model a 1-D unsteady Euler equation with source terms is considered. The flow is assumed as a non-reacting mixture of perfect gases with space and time varying thermo physical properties. The governing equations in the combustion chamber are solved numerically by using the Steg...

Mechanisms of energy dissipation during solid-solid and solid-liquid friction are discussed. A conservative van der Waals adhesion force, when combined with surface imperfectness, such as deformation, leads to adhesion hysteresis (AH). When an asperity slides upon a substrate, the substrate is subjected to a loading-unloading cycle, and energy is dissipated due to the AH. Another mechanism, whi...

an analytical model is proposed and an analysis is conducted for solid oxide fuel cells with goals of higher power densities. the analytical model is designed to help optimize the size, spacing, and geome-trical shapes of current collectors. the model fully considers the ohmic, species concentration, and activa-tion polarizations. from the analysis of several cases, it is recommended that 3d pi...

A Monte Carlo simulation study is made of the phase diagram of the restricted primitive model and of the solid± liquid and solid± solid phase coexistence curves in particular. At low temperatures, there is liquid± bcc coexistence and with increasing density there is bcc± fcc coexistence. These coexistence curves end in a triple point (liquid± bcc ± fcc) above which only liquid± fcc coexistence ...