Triply Periodic Co-continuous piezocomposites, which consist of a ferroelectric-ceramic phase and an elastic-polymer phase continuously interconnected in three dimensions (3D), are emerging flexible piezoelectric materials with high efficiency in absorbing and converting multi-directional mechanical stimuli into electrical signals. Current co-continuous piezocomposites cannot be achieved with controlled piezoelectric properties due to the limited capability of traditional fabrication methods in carefully controlling the morphology of each phase, additive manufacturing such as Suspension-Enclosing Projection-Stereolithography process thus was selected. Porous ceramic skeleton with randomly distributed grain size is commonly observed in sintered ceramic skeleton fabricated by additive manufacturing. The effective piezoelectric properties of the piezocomposites were thus studied utilizing a two-scale method. Through analyzing the simulated results of different process parameters, optimal parameters of 3D printing processes including post-processes was subsequently suggested.

Approximately 37 m (120 ft) of core was studied with the objective of evaluating and documenting the development and loss of porosity in the dry Mobil McElroy-1 well (Lower Cretaceous Aptian – Albian Sligo Formation). Core slabs were described and thin section samples, taken every 1.5 m (5 ft), were stained and analyzed under standard petrographic, cathode luminescence, confocal and scanning electron microscopes. The main conclusion is that average porosity significantly reduced with depth. Carbon and oxygen isotope values obtained for 20 samples show that the main pore-occluding diagenetic environment was meteoric with most samples having relatively low delta18O (-3.1%o to -6.7%o V- PDB) values. Early through late stage medium (1 mm – 3 mm) to large (> 3 mm) calcite and nonerroan dolomite jointly contributed to more than 10% of primary porosity loss. This study significantly contributes to the understanding of the Sligo Formation and promotes development of natural gas resources.

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The advancement of both electronics and instrumentation technology has fostered the development of multi-physics platforms that can probe the earth’s subsurface. Remote, non-destructive testing techniques have led to the increased deployment of electromagnetic waves in sensor technology. Electromagnetic wave techniques are reliable and have the capacity to sense materials and associated properties with minimal perturbation. However, meticulous data analyses and mathematical derivations reveal inconsistencies in some formulations. Thus, revisiting the fundamental physics that underlies both electrical impedance experimental setups and electromagnetic properties are paramount. This study aims to unravel inherent limitations in the understanding of the relationships between electromagnetic and non-electromagnetic properties that are relevant to the characterization of fluids in porous media. These correlations pervade porosity, permeability, specific surface, pore size distribution, tortuosity, fluid discrimination, diffusion coefficient, degree of saturation, viscosity, temperature, phase transformation, miscibility, salinity, and the presence of impurities. The focus is on the assessment of liquids, soils, rocks, and colloids using broad spectral frequency complex permittivity, conductivity, magnetic permeability, and nuclear magnetic resonance relaxometry. Broadband electrical properties measurement for saturated porous media can provide multiple physical phenomena: Ohmic conduction, electrode polarizations, Maxwell-Wagner spatial polarizations, rotational, and segmental polarizations. Liquids dominate the electromagnetic signatures in porous media as dry minerals are inherently non-polar and non-conductive. Results reveal that voltage drops due to the discontinuity of charge-carrier at the electrode-electrolyte interface named electrode polarization inherently affect the low-frequency electrical measurements both in two- and four-probe configurations. Rotational polarizations that occur in MHz-GHz ranges are defined by the electrical dipole moment and effective molecular volume. Both viscosity and effective molecular volume govern the NMR transverse relaxation time. An engineered soil suspension with ferromagnetic inclusions exhibits excellent characteristics for drilling fluid application. Overall, the study highlights the complementary nature of conductivity, permittivity, and NMR relaxation for the advanced characterization of fluid saturated geomaterials.

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This thesis describes research to understand the relationships between materials, microstructure, transport processes, and battery performance for primary alkaline battery cathodes. Specifically, the effect of various carbon additives, with different physical properties, on electronic transport or conductivity within battery cathodes was investigated. Generally, the electronic conductivity increases with carbon additives that have higher aspect ratios, smaller particle diameters, higher surface areas, and lower bulk densities. Other favorable carbon aspects include more aggregated and elongated carbon domains which permit good particleto-particle contacts. Of the various carbon additives investigated, graphene nanopowder was the best performer. This graphene nanopowder had the smallest particle diameter, highest surface area, and one of the lowest Scott densities of the carbon additives investigated as well as well-connected, interspersed carbon pathways. Notably, a typical effective ionic conductivity is more than 50 times less than the electronic conductivity (5.7 S/m to 300 S/m, respectively) for a high-performance cathode. Thus, alkaline battery cathodes could be redesigned to improve ionic conductivity for optimal performance. This work expanded on previously published work by relating additional carbon-additive material properties--specifically, particle morphology, surface area and Scott density--and their corresponding cathode microstructure to the fundamental transport processes in alkaline battery cathodes.

This thesis describes experimental investigation of thermal and combustion phenomena as well as structure for self- propagating combustion synthesis of porous Ni - Ti intermetallic aimed for structural biomedical application. The control parameters for the porosity distribution have been investigated experimentally through varying the preheat temperature, initial porosity, initial elemental particle size, and applied pressure during the fabrication process. Ni and Ti elemental powders are mixed using a 1:1 ratio. The mixture is compressed using several different compression forces to produce cylindrical samples of 1.1 cm diameter and 2-3cm length, with initial porosity ranging from 30% to 40%. The samples are preheated to various initial temperatures and ignited from the top surface such that the flame propagates axially downwards. The combustion reaction is recorded with a motion camera. An infrared sensor is used to record the temperature profile during the combustion process. The samples are then cut using a diamond saw in both longitudinal and transverse directions. Image analysis software is then used to analyze the porosity distribution in each sample.

This paper presents an innovative experimental approach for simultaneous measurements of the suction head, volumetric water content, and the acoustic admittance of unsaturated sands. Samples of unsaturated sands are tested under controlled laboratory conditions. Several types of uniform sand with a wide range of particle sizes are investigated. The reported experiments are based on a standard Buchner funnel setup and a standard acoustic impedance tube. It is a novel, nondestructive, and noninvasive technique that relates the key geotechnical parameters of sands such as volumetric water content, density, and grain-size distribution to the acoustic admittance and attenuation. The results show a very sensitive dependence of the acoustic admittance on the volumetric water content controlled by the value of suction head applied. Analysis of the obtained data demonstrates that the relationship between the volumetric water content and the real part of the surface admittance in the frequency range of 400–1,200 Hz can be represented using a logarithmic equation. It is found that the coefficients in the proposed equation are directly related to the uniformity coefficient and the acoustic admittance of the dry sample, which can easily be measured or predicted for a broad range of sands. A validation exercise is conducted to examine the accuracy of the proposed equation using a sand sample with markedly different properties. The results of the validation exercise demonstrate that the proposed relations can be used to determine very accurately the volumetric water content within the porous specimen from the acoustical data. The error in the acoustically measured volumetric water content is found to be ±2.0% over the full range of volumetric water contents ( 0≤θ≤n , where n is the sample porosity).

Microporous carbonates host a significant portion of the remaining oil-in-place in the giant carbonate reservoirs of the Middle East. Improved understanding of petrophysical and multi-phase flow properties at the pore-scale is essential for the development of better oil recovery processes. These properties strongly depend on the 3D geometry and connectivity of the pore space. In this study, we harnessed the unique capabilities of fluorescence confocal laser scanning microscopy (CLSM) to capture both macroporosity and microporosity, down to 0.1 µm, to provide a more representative 3D representation of pore space compared to traditional methods. The experimental procedure developed was specifically designed to enable highresolution confocal 3D imaging of the pore space of carbonate systems. The protocol aims to render carbonates more "transparent" to CLSM by imaging etched epoxy pore casts of the sample and minimizing CLSM signal scattering. The resulting highquality 3D images of the multi-scale pore space allow more reliable petrophysical interpretation and prediction of transport properties. Additionally, we present a robust pore imaging approach that correlates 2D images produced by scanning electron microscopy (SEM) with the 3D models produced by CLSM that cover a range of scales, from millimeters in 3D to micrometers in 2D. For the first time, multi-color fluorescence confocal imaging was employed to characterize the geometric attributes of a porous medium. We foresee that the protocol developed in this study could be used as a standard protocol for obtaining high-quality 3D images of epoxy pore casts using confocal microscopy, and could contribute to improved characterization of micritic carbonate reservoirs and oil recovery methods. We also demonstrate the advantages of multi-scale and multi-color confocal images in realizing more accurate evaluations of petrophysical properties. Finally, we demonstrate that micro 3D printing (two-photon polymerization) can potentially be used to fabricate micromodels with sufficient resolution to capture the geometric attributes of micritic carbonates and that can replicate the inherent 3D interconnectivity between macro- and micro-pores.