We investigate the gas flow behavior of unidirectional porous ceramics processed by ice-templating. The pore volume ranged between 54% and 72% and pore size between 2.9 [Formula: see text]m and 19.1 [Formula: see text]m. The maximum permeability ([Formula: see text] [Formula: see text] m[Formula: see text]) was measured in samples with the highest total pore volume (72%) and pore size (19.1 [Fo...

The theoretical mechanism for realizing a negative refractive index material in an optical frequency range with an atomic gas system of electromagnetically induced transparency (EIT) is studied. It is shown that under certain conditions such a dense gas can exhibit simultaneously negative permittivity and negative permeability, and negligibly small loss.

The state of the ground can change dramatically in response to changing meteorological influences and physical disturbances of the ground (e.g. tilling) that are important to many civilian and military activities. Permeability is the fundamental parameter of a porous media that controls whether a surface is an acoustically hard one, through which fluids may not easily penetrate, or conversely a...

The performances of two-phase polymer-liquid PEBAX®/polyethylene glycol (PEG) and three-phase polymer-liquid-solid PEBAX®/PEG/MWNT thin film composite membranes for CO2 and CH4 permeation were studied. The effect of temperature and MWNT/PEBAX® ratio on single gas (CO2 and CH4) permeability was investigated. The permeat...

The nonhomogeneous gas or fluid flowing through a nonhomogeneous porous medium is studied. An interesting phenomenon is discussed which shows that the state of the flow is not affected by the surrounding environment if some hypotheses are made on the porosity of the gas, the viscosity, and the permeability of the medium. Such a state is called an isolated environment. The conditions under which...

Using of nanocomposite membranes composed of polymer and inorganic nanoparticles is a novel method to enhance gas separation performance. In this study, membranes were fabricated from polyester (PE) containing silica (SiO2) nanoparticles and gas permeation properties of the resulting membranes were investigated. Morphology of the membranes, SiO2 distribution a...

We combine a new pore-scale model with a reservoir simulation algorithm to predict gas production in gas-bearing shales. It includes an iterative verification method of surface mass balance to ensure real-time desorption-adsorption equilibrium with gas production. The pore-scale model quantifies macroscopic petrophysical properties of formations using an algorithm of gas transport in porous med...

This paper discusses different important gas permeation models such as “Maxwell”, “Bruggeman”, “Lewis-Neilson”, and “Pal” models to predict “Mixed Matrix Membranes” (MMMs) performance. The main parameter considered and discussed is the permeability of Hydrogen on Carbon Nanotubes (CNTs)-MMM. For evaluation of the theoretical models, experimental data of permeability for H2 were compa...

The performances of two-phase polymer-liquid PEBAX®/polyethylene glycol (PEG) and three-phase polymer-liquid-solid PEBAX®/PEG/MWNT thin film composite membranes for CO2 and CH4 permeation were studied. The effect of temperature and MWNT/PEBAX® ratio on single gas (CO2 and CH4) permeability was investigated. The permeat...