The presence of particles in liquid-solid fluidized beds enhances the bed heat transfer, because the movement of the particles leads to an increased turbulence in the system. Moreover, the violent movement of the particles has a positive effect on fouling of the heat transfer surface. The aim of this investigation was to perform systematic measurements of bed voidage and heat transfer coeff...

Molecular dynamics and Langevin dynamics simulations are used to elucidate the behavior of liquid atoms near a solid boundary. Correlations between the surface wettability and spatial variations in liquid density and structure are identified. The self-diffusion coefficient tensor is predicted, revealing highly anisotropic and spatially varying mass transfer phenomena near the solid boundary. Th...

The response of an extended periodic system to a homogeneous field ~of wave-vector q50) cannot be obtained from a q50 time-dependent density functional theory ~TDDFT! calculation, because the RungeGross theorem does not apply. Time-dependent current–density functional theory is needed and demonstrates that one key ingredient missing from TDDFT is the macroscopic current. In the low-frequency li...

The Airy gas model of the edge electron gas is used to construct an exchange-energy functional which is an alternative to those obtained in the local density and generalized gradient approximations. Test calculations for rare gas atoms, molecules, solids and surfaces show that the Airy gas functional performs better than the local density approximation in all cases and better than the generaliz...

Porous materials are ubiquitous in the universe and weathering of porous surfaces plays an important role in the evolution of planetary and interstellar materials. Sputtering of porous solids in particular can influence atmosphere formation, surface reflectivity and the production of the ambient gas around materials in space. Several previous studies and models have shown a large reduction in t...

if solid wastes are not collected and disposed properly, can cause environmental pollution which affect human health, animals and plants. also aesthetic aspect of solid waste disposal is important. therefore proper management is necessary. this study was carried out for the identification and classification of solid waste produced by oil drilling company temporary camps based on rcra act and un...

We examine sedimentation density profiles of star polymer solutions as an example of colloidal systems in sedimentation equilibrium that exhibit reentrant melting in their bulk phase diagram. Phase transitions between a fluid and a fluid with an intercalated solid are observed below a critical gravitational strength alpha*. Characteristics of the two fluid-solid interfaces in the density profil...

Near a fluid-solid interface, the fluid spatial density profile is highly nonuniform at the molecular scale. This nonuniformity can have profound effects on the dynamical behavior of the fluid and has been shown to play an especially important role when modeling a wide variety of nanoscale heat and momentum transfer phenomena. We use molecular-mechanics arguments and molecular-dynamics (MD) sim...