Porosity Network Research Articles

Geophysical methods in terrestrial material property determinations: Bliamptis, EE Air Force Cambridge Res Lab, USA Thomson, KC Defense Nuclear Agency, USA US Air Force Cambridge Research Lab Report AFCRL-TR-75-0393, 23, July, 1975, 37P

Abstract : In-house and contractual research was conducted on the relationships between mechanical (strength) properties of rock and soil material and their electrical properties. A theoretical study involved the quantum electromagnetic and elastic interactions of crystals and solids. Laboratory and field investigations were made of the porosity and surface crack networks of large masses of quarry rocks, which govern their conductivity and permittivity. Thermal and mechanical stressing of rocks were analyzed. Electrical parameters of deep mine rocks were measured in-situ with emphasis on frequency/conductivity relationships. Direct mapping of rock strength as a function of electrical resistivity was investigated in the field. A three-dimensional modeling program was conducted in the laboratory. Field measurements of dynamic electrical conductivity of various earth materials were made under conditions of a rapid stress generated by high explosive setonations. Correlations demonstrated by this geophysical and geological research can be useful in prediction or evaluation of nuclear weapon shock effects on military installations.

The direct observation of open porosity networks

The direct observation of open porosity networks

Dental stereoroent genography

The use of X-ray micro computed tomography (X-ray micro-CT) for three-dimensional (3D) characterization of multiphase systems continues to increase in metallurgical research. In recent years, a number of technical developments in X-ray sources and X-ray imaging arrays have broadened the utility of micro-CT. Here, the authors review the current state-of-the-art tomographic techniques for both qualitative and quantitative geometallurgical characterization. This review first considers the basic principles of tomography and commonly used tomographic systems. The advantages and disadvantages (shortcomings) of micro-CT are discussed. Software development, including current image reconstruction algorithms, such as traditional weighted back projection and iterative reconstruction algorithms, as well as image segmentation tasks, are then discussed for processing 3D images and conducting quantitative analysis. Based on the development of hardware and software, applications involved in geometallurgy and minerals engineering are then thoroughly discussed. Specifically, applications include the determination of microstructure such as particle size, shape, and damage, as well as porosity and pore network structure of packed particle beds. In this way, the permeability, mineral composition, coal washability, mineral liberation, and exposed grain surface area can be determined.