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...

In the present paper, we have studied MHD free convective two dimensional unsteady viscous incompressible flows through a porous effect bounded by an infinite vertical porous plate with constant suction. The permeability of the porous medium fluctuates in time about a constant mean, and the viscosity of fluid is assumed to vary as a linear function of temperature. The flow is permitted under th...

permeability is a key parameter in reservoir characterization. in fact, without accurate information about reservoir permeability, there is no good solution for reservoir engineering problems. up to now, permeability values of a reservoir have been calculated through laboratory measurements or well testing methods. these methods are useful but they cannot describe a reservoir reliably and preci...

A global nonlinear stability analysis is performed for a couple-stress fluid layer heated from below saturating a porous medium with temperature-pressure dependent viscosity for different conducting boundary systems. Here, the global nonlinear stability threshold for convection is exactly the same as the linear instability boundary. This optimal result is important because it shows that lineari...

Proton exchange membranes (PEM) for a direct methanol fuel cell (DMFC) have main drawbacks which are methanol permeability, reduced proton conductivity and the cost of the membrane. This paper reviews different polymeric materials such as fluorinated, non-fluorinated, acid-base complex, and composite membranes for DMFC. Currently, nonfluorinated membranes gain a lot of atte...

Net pay thickness is defined as that portion of a reservoir which contains economically producible hydrocarbons with today’s technology, prices, and costs. This thickness is a key parameter of the volumetric calculation of in-place hydrocarbons, well test interpretation, and reservoir characterization. A reservoir interval is considered as net pay when it contains hydrocarbons that can flow at ...

This paper presents an experimental program on rapid chloride permeability test on lightweight concrete produced from oil palm clinker aggregates. Oil palm clinker is obtained from by-product of palm oil milling. Utilising oil palm clinker in concrete production not only solves the problem of disposing this solid waste but also help to converse natural resources. The parameter of investigation ...

A technique of determination of complex permittivity and permeability of ferrimagnetic nanopowders using S-parameter measurements in rectangular waveguide and results of its study are presented in this paper. The permittivity and permeability of the ferrimagnetic nanopowders are determined by the novel technique in which magnitudes of S-parameters are used only. Use of the technique allows to s...

In many reservoir studies, anisotropic permeability values in orthogonal directions are often considered to have simple relationships. Often, this permeability anisotropy is modeled only between the vertical and horizontal directions as a certain ratio of values, while permeability values in a horizontal plane are considered equal. In reality, the depositional history of the reservoir results i...

BACKGROUND The aim of the present study was to analyze variations in permeability of albumin and immunoglobulin G (IgG) influx into cerebrospinal fluid (CSF) in a clinical setting. METHODS In a retrospective intra-individual comparison of CSF samples, we used the IgGIndex and its constituents to indicate alterations in IgG/albumin permeability. RESULTS We found altered IgGIndices in 25/64 p...