Permeability anisotropy

Random vs nonrandom liber polymer composite modulus hardness liquid permeability Anisotropy of physical properties... 

To make our discussion convenient, we shall describe the o increase caused by molecular hydrogen in interlayer space introducing an additive to JI parameter (x) increasing with x and characterizing the degree of dielectric permeability anisotropy for the medium comprised by the exciton in the following form ... 

One can say that the obtained by us experimental results upon 2D exciton localization (taking place due to the growth of the crystal dielectric permeability anisotropy parameter) with o are very close to [27] where the behaviour of polaron excitons in parabolic quantum dots were considered and shown that the dot size decrease results in increasing the exciton binding energy. 

Leroueil S., Boudin G., Tavenas F., Bergeron L. and La Rochelle P. (1990). "Permeability anisotropy of natural clays as a function of strain." Canadian Geotechnical Journal 27 568-579. 

Internal transfer (conductivity, diflusivity, permeability, anisotropy ratios) Dimensions (lei th, thickness)... 

U.S. Patent Application, Multi-Probed Pressure Transient Analysis for the Determination of Horizontal Permeability, Anisotropy, and Skin, Considering Storage and Dipping Angle, Sept. 2001... 

Sedimentation can create an intrinsic permeability anisotropy (caused by preferential directions of connected pore channels). 

Ye et al. (1999) investigated outcrop samples of the Bluejacket Sandstone (Middle Peimsylvania) and correlated permeability anisotropy with the internal facies architecture meandering channel-fill facies shows strong permeability anisotropy compared with low anisotropy of braided channel-fill facies. 

For laminated shaly sand, a dramatic decrease of permeability in the vertical direction can be expected because the flow is COTitroUed by the low shale permeability, whereas in the horizontal direction, the magnitude of permeability is still controlled by the sand fraction for moderate shale content also. This creates permeability anisotropy. 

Optimum permeability is achieved by choosing the composition where the anisotropy constants X are near zero, by using high purity raw... 

Heterogeneity, nonuniformity and anisotropy are terms which are defined in the volume-average sense. They may be defined at the level of Darcy s law in terms of permeability. Permeability, however, is more sensitive to conductance, mixing and capillary pressure than to porosity. 

Heterogeneity, nonuniformity and anisotropy are based on the probability density distribution of permeability of random macroscopic elemental volumes selected from the medium, where the permeability is expressed by the one-dimensional form of Darcy s law. 

Permeability is a volume-averaged property for a finite but small volume of a medium. Anisotropy in natural or manmade packed media may result from particle (or grain) orientation, bedding of different sizes of particles or layering of media of different permeability. A dilemma arises when considering whether to treat a directional effect as anisotropy or as an oriented heterogeneity. 

The introduction of large gas phase volumes into the polymer alters the physical characteristics of the material volume weight, permeability to fluids and gases, and physico-mechanical properties. Moreover, the properties of the polymer matrix itself are changed (owing to orientation effects, supermolecular structure of the polymer in the walls, ribs and tension bars of cells), which drives up the value of specific strength on impact, and results in anisotropy of elasticity. 

The flow velocity, pressure and dynamic viscosity are denoted u, p and fj and the symbol (...) represents an average over the fluid phase. Kim et al. used an extended Darcy equation to model the flow distribution in a micro channel cooling device [118]. In general, the permeability K has to be regarded as a tensor quantity accounting for the anisotropy of the medium. Furthermore, the description can be generalized to include heat transfer effects in porous media. More details on transport processes in porous media will be presented in Section 2.9. 

Two outstanding properties of FeB metallic glasses are their low magnetic permeabilities and their low acoustic attenuations. The former results from their lack of magnetic anisotropy and has led to their use in power transformers, theft detectors, and various electronic devices. The latter results from the very low dislocation mobility in them. 

For each thickness, at least 10 different flow rate measurements were obtained in order to cover the range of flow rates that a DL experiences during normal fuel cell operation. To obfain fhe corresponding permeabilify, fhe pressure drop resulfs were ploffed as a function of the mass flow rate. After this, the Forchheimer equation was fitted to the plotted data to determine the viscous and inertial permeabilities. As expected, the in-plane permeabilities of each sample DL maferial decreased when the compression pressure was increased. It is also important to mention that these tests were performed in two perpendicular directions for each sample in order to determine whether any anisotropy existed due to fiber orienfation. 

The magnetic properties of iron oxides can be determined using Mossbauer spectroscopy, neutron powder diffraction and magnetometry (see Chap. 7). The characteristic parameters are the magnetic moment, the permeability, the saturation magnetization, the magnetic anisotropy constants and the Bhf (Tab. 6.2). 

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