This research studies the chemical nature of zirconia and the complex surface chemistry of zirconia in order to better comprehend its behavior under chromatographic conditions. This research shows how the physical and chemical properties of zirconia depend strongly on the thermal treatment during synthesis. The morphology of the samples was also studied. The absorption capability of Adenosine Triphosphate (ATP) on zirconia was also monitored and spectrally characterized. The results of this research showed how the properties of zirconia vary with thermal treatment. It was observed that the zirconia prepared at a higher temperature had lower surface area, lower pore size and pore volume as compared to the zirconia prepared at a lower temperature. The morphology studies showed the porosity of the zirconia. The results from the absorption experiments showed that zirconia prepared at a higher temperature absorbed more ATP than the zirconia prepared at a lower temperature. Significant changes were also observed on the pellets of zirconia pre and post absorption experiments. I hope that this research sheds more light on the complex properties of zirconia’s surface chemistry and the results of this study could better help in the application and use of zirconia in chromatography to separate proteins.

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In this dissertation¡Atwo topics in microbubble systems are investigated¡G1) Pore Formation from Bubble Entrapment by a Solidification Front¡F2) Pore formation in Solid¡C In the first study¡Amechanism of the pore shape in solid resulted from a tiny bubble captured by a solidification front is geometrically and generally investigated¡CPore formation and its shape in solid are one of the most critical factors affecting properties¡Amicrostructure¡Aand stresses in materials¡CFor simplicity without loss of generality, the tiny bubble beyond the solidification front is considered to have a spherical cap in this work¡CIntroducing a geometrical analysis it is found that the contact angle of the bubble cap can be governed by the Abel¡¦s equation of the first kind in terms of displacement of the solidification front¡CThe pore can be elongated, expanded¡Ashrunk and closed¡Adepending on relative variation of the bubble growth rate and solidification rate¡CThe pore can be closed by imposing infinitesimal bubble growth rate-to-solidification rate ratio¡Aand a finite bubble growth-to-solidification rate ratio in order to produce a minimal bubble radius at the contact angle of ¡CA criterion intuitively accepted in the literature¡Astating that closure of a pore is attributed to a greater solidification rate than bubble growth rate¡Ais incorrect¡CThe predicted pore shape and contact angle agree with experimental observations¡CManipulating either bubble growth rate or solidification rate can control pore formation in solid¡C In second study¡Athe shapes of a growing or decaying bubble entrapped by a solidification front are predicted in this work¡CThe bubble results from supersaturation of a dissolved gas in the liquid ahead of the solidification front¡CPore formation and its shape in solid are one of the most critical factors affecting properties¡Amicrostructure, and stresses in materials¡CIn this study¡Athe bubble and pore shapes entrapped in solid can be described by a three-dimensional phase diagram¡Aobtained from perturbation solutions of Young-Laplace equation governing the tiny bubble shape in the literature¡CThe predicted growth and entrapment of a microbubble as a pore in solid are found to agree with experimental data¡CThis work thus provides a realistic prediction of the general growth of the pore shape as a function of different working parameters¡C

Fractured reservoirs have been traditionally idealized using dual-porosity models. In these models, all matrix and fractures systems have identical properties. However, it is not uncommon for naturally fractured reservoirs to have orthogonal fractures with different properties. In addition, for hydraulically fractured reservoirs that have preexisting natural fractures such as shale gas reservoirs, it is almost certain that these types of fractures are present. Therefore, a triple-porosity (dual-fracture) model is developed in this work for characterizing fractured reservoirs with different fractures properties. The model consists of three contiguous porous media: the matrix, less permeable micro-fractures and more permeable macro-fractures. Only the macro-fractures produce to the well while they are fed by the micro-fractures only. Consequently, the matrix feeds the micro-fractures only. Therefore, the flow is sequential from one medium to the other. Four sub-models are derived based on the interporosity flow assumption between adjacent media, i.e., pseudosteady state or transient flow assumption. These are fully transient flow model (Model 1), fully pseudosteady state flow model (Model 4) and two mixed flow models (Model 2 and 3). The solutions were mainly derived for linear flow which makes this model the first triple-porosity model for linear reservoirs. In addition, the Laplace domain solutions are also new and have not been presented in the literature before in this form. Model 1 is used to analyze fractured shale gas horizontal wells. Non-linear regression using least absolute value method is used to match field data, mainly gas rate. Once a match is achieved, the well model is completely described. Consequently, original gas in place (OGIP) can be estimated and well future performance can be forecasted.

Pressure drops over a packed bed of pebble bed reactor type are investigated. Measurement of porosity and pressure drop over the bed were carried out in a cylindrical packed bed facility. Air and water were used for working fluids. There are several parameters of the pressure drop in packed beds. One of the most important factors is wall effect. The inhomogeneous porosity distribution in the bed and the additional wetted surface introduced by the wall cause the variation of pressure drop. The importance of the wall effects and porosity can be explained by using different bed-to-particle diameter ratios. Four different bed-to-particle ratios were used in these experiments (D/dp = 19, 9.5, 6.33 and 3.65). A comparison is made between the predictions by a number of empirical correlations including the Ergun equation (1952) and KTA (by the Nuclear Safety Commission of Germany) (1981) in the literature. Analysis of the data indicated the importance of the bed-to-particle size ratios on the pressure drop. The comparison between the present and the existing correlations showed that the pressure drop of large bed-to-particle diameter ratios (D/dp = 19, 9.5and 6.33) matched very well with the original KTA correlation. However the published correlations cannot be expected to predict accurate pressure drop for certain conditions, especially for pebble bed with D/dp (bed-to-particle diameter ratio) </= 5. An improved correlation was obtained for a small bed-to-particle diameter ratio by fitting the coefficients of that equation to experimental database.

With increase of interest in exploiting shale gas/oil reservoirs with multiple stage fractured horizontal wells, complexity of production analysis and reservoir description have also increased. Different methods and models were used throughout the years to analyze these wells, such as using analytical solutions and simulation techniques. The analytical methods are more popular because they are faster and more accurate. The main objective of this paper is to present and demonstrate type curves for production data analysis of shale gas/oil wells using a Dual Porosity model. Production data of horizontally drilled shale gas/oil wells have been matched with developed type curves which vary with effective parameters. Once a good match is obtained, the well dual porosity parameters can be calculated. A computer program was developed for more simplified matching process and more accurate results. As an objective of this thesis, a type curve analytical method was presented with its application to field data. The results show a good match with the synthetic and field cases. The calculated parameters are close to those used on the synthetic models and field cases.

Abstract The studies measure the porosity, permeability of porous structures with different grain size and shapes such as those of crushed gravels and glass balls. Then discuss the relationship between various coefficients like intrinsic permeability, dimensionless turbulent coefficient, Reynolds number and so on in previous experimental formula¡]Ward¡A1964¡^and writer's formula from practical physics conceptions . Physics conceptions particularly consider respectively sheer flow effect and vortex effect in porous flow field. The study will be considered as the first phase in a full study of the resistance force inside porous structure.