In this work we present measurements of permeability, effective porosity and tortuosity on a variety of rock samples using NMR/MRI of thermal and laser-polarized gas. Permeability and effective porosity are measured simultaneously using MRI to monitor the inflow of laser-polarized xenon into the rock core. Tortuosity is determined from measurements of the time-dependent diffusion coefficient us...

We investigated four acrylic cement preparation techniques for their effects on cement porosity: hand mixing, pressurization in a pneumatic pistol, centrifugation, and vacuum mixing. All the techniques were tested on three types of cement with different viscosity characteristics. The best results were obtained with vacuum mixing using a newly designed experimental system, yielding porosity redu...

[1] We present a model for the study of the effect of rheological hysteresis on compaction in sedimentary basins, when surface loading and unloading occurs. When compaction is slow (sedimentation rate is large and/or permeability is small), the hysteresis has little effect on the basal compaction layer, but in the more realistic case where compaction is fast (i.e., sedimentation is slow and/or ...

Results and Conclusion: The analysis results show that the cracking deflection of the prestressed, concrete beams increases with the increase in the porosity of the grouting material of the beams under different load forms. By contrast, under the same porosity grouting material, the cracking deflection of the symmetrical loads is larger than that of the uniform and concentrated loads. As the po...

The finite element method (FEM) is used to study the influence of porosity and pore shape on the elastic properties of model porous ceramics. The Young’s modulus of each model was found to be practically independent of the solid Poisson’s ratio. At a sufficiently high porosity, the Poisson’s ratio of the porous models converged to a fixed value independent of the solid Poisson’s ratio. The Youn...

Effective mass-transfer kinetics depend on particle-size distribution (PSD) and particle porosity (among other complex phenomena). The porediffusion flux can vary with adsorbate loading – if the amount of adsorbed species is sufficiently large it can lead to hindrance effects that substantially change particle porosity. By use of batch kinetic adsorption experiments the general rate model was u...

Therefore, the new method, called the grey level method, which reflects the phenomenon of image processing and computation of ration between the volume of voids and the total volume of the entire sample, was considered and improved in term of image noise and artifacts. The volumes of 2D CT image as a surface are achieved by means of integrating the surface with operations relating to image hist...

The influence of interface porosity on the wetting properties of colloid-polymer mixtures is studied within density functional theory for the Asakura-Oosawa-Vrij model at the surface of a quenched hard-sphere matrix. While the porosity hardly changes the location of the transition from partial to complete wetting at colloidal bulk gas-liquid coexistence, the onset of wetting, as signaled by the...

Porosity is a result of a deficiency in the production process that could lead into the mechanical degradation of CFRP composite structures. Therefore, some checkpoints for determining its presence during part manufacturing have to be established, verifying that precise threshold values are not exceeded. Currently, porosity characterization is carried out by an indirect way using ultrasonic tec...

The electrical properties of sol-gel prepared aluminosilicate films were investigated for suitability in electronic applications. The aluminosilicate films exhibited apparent closed porosity and a dielectric constant as low as = 5 with processing temperatures from 373 K to 873 K. The porosity was inaccessible to nitrogen at 77 K, helium at 293 K, and water vapor at 293 K. Both bulk and thin-fil...