The synthesis of the sodium salt of heptakis (2, 3-di-O-acetyl-6-O-sulfo)-β-cyclodextrin was modified to increase the isomeric purity to 98.5%. This salt was used to obtain the organic-solvent-soluble, single-isomer, charged tetrabutylammonium salt of heptakis (2, 3-di-O-acetyl-6-O-sulfo)-β-cyclodextrin. Its isomeric purity was higher than 99%, as determined by CE, and its structure was confirmed by NMR and ESI-MS analysis. The hydrophobic single-isomer cyclodextrin was utilized to separate the enantiomers of weak base analytes in aprotic media by capillary electrophoresis. The effective mobilities and separation selectivities follow trends observed with negatively charged cyclodextrins in amphiprotic solvents. The properties of the dissolved cyclodextrin are altered by its counter ion, thereby affecting the separations of enantiomers. The aprotic media allow the modification of the separation selectivity, since the binding strength of the enantiomers to the cyclodextrin is intermediate between that reported in aqueous and methanolic buffers.

The objective of this research is to develop and test a new concept for predicting permeability from routine rock properties. First, we develop a model predicting permeability as a function of capillary pressure. Our model, which is based on the work by Purcell, Burdine and Wyllie and Gardner models, is given by: (Equation 1 - See PDF) Combining the previous equation and the Brooks and Corey model for capillary pressure, we obtain: (Equation 2 - See PDF) The correlation given by this equation could yield permeability from capillary pressure (and vice-versa). This model also has potential extensions to relative permeability (i.e., the Brooks and Corey relative permeability functions) - which should make correlations based on porosity, permeability, and irreducible saturation general tools for reservoir engineering problems where relative permeability data are not available. Our study is validated with a large range/variety of core samples in order to provide a representative data sample over several orders of magnitude in permeability. Rock permeabilities in our data set range from 0.04 to 8700 md, while porosities range from 0.3 to 34 percent. Our correlation appears to be valid for both sandstone and carbonate lithologies.

The chicken has long been a model used for the study of plasma lipoproteins due to the ability to increase VLDL production by administration of estrogen. In this study we were able to demonstrate successful isolation of VLDL assembly intermediates from the livers of hens, roosters, and estrogen treated rosters. Particle diameter of first step particles, as determined by dynamic laser light scattering, was decreased from an average diameter of 31.5 nm in untreated birds, to 16.1 nm 12 hours after estrogen treatment. Effects of estrogen waned after 24 hours and particle diameter of first step particles increased to an average of 23.9 nm. These assembly intermediates, as well as plasma VLDL and VLDLy, were successfully studied using capillary electrophoresis (CE). Effective mobilities of intact plasma VLDL and first step particles decreased after estrogen administration. Hen VLDL showed a single uniform peak whereas rooster VLDL separated into distinct “subclasses”. Delipidated VLDL, VLDLy and first step assembly intermediates were also successfully separated using CE. This thesis is dedicated to my family who always encouraged me through this process.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references. Available also in a digital version from Dissertation Abstracts.

Thesis (Ph.D.)--Drexel University, 2009. / Includes abstract and vita. Includes bibliographical references (leaves 117-118).

Thesis (Ph.D.)--Drexel University, 2009. / Includes abstract and vita. Includes bibliographical references (leaves 180-183).

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.

Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xiii, 110 p. : ill. (some col.) + 4 video files. Includes four QuickTime video files. Vita. Includes abstract. Includes bibliographical references (p. 109-110) and index.

A capillary barrier develops and restricts water flow when two porous materials with dissimilar pore structures (e.g., a coarse-grained soil overlain by a fine-grained soil) are in contact with one another. This is due to a difference in the unsaturated hydraulic conductivity of the two materials at a given suction. Geotextiles are utilized in a variety of civil engineering applications and have a pore structure similar to that of a coarse-grained soil. This can be problematic in unsaturated soil as the capillary barrier caused by the geotextile may instigate undesirable moisture buildup in the overlying soil and undermine any benefit provided by the geotextile. Various versions of a new geotextile have been manufactured to help dissipate a capillary barrier by "wicking" or laterally draining excess moisture away from the soil. Additionally, nonwoven blends of the unique wicking fiber combined with standard polymeric fibers are tested to assess their ability to minimize the development of a geotextile capillary barrier and not cause additional moisture accumulation in the first place. The unsaturated properties of both woven and nonwoven configurations of these wicking geotextiles were investigated as part of a comprehensive an experimental testing program. The testing program includes small soil column infiltration tests to assess geotextile capillary barrier performance with moisture monitored by time domain reflectometers and capacitance probes. Also, modified hanging column tests were conducted to define the hydraulic properties of the geotextiles in the form of water retention curves. Finally, a microscopy study, involving both optical and scanning electron microscopes, was conducted to observe the wicking behavior of the geotextiles at a micro-scale level. Test results illustrate the enhanced lateral drainage and reduced moisture accumulation of the wicking geotextiles when compared to regular geotextiles. Additionally, the woven version of the wicking geotextile has the potential to perform the functions of separation, filtration, protection, reinforcement, and drainage. All of these functions in a single geosynthetic product could lead to significant cost savings compared to the use of separate products to perform each one of the various functions. / text

CO₂ sequestration aims for the most efficient utilization of reservoir pore volume and for maximizing security of storage. For typical field conditions and injection rates, buoyancy and capillary forces grow dominant over viscous forces within hundreds of meters of the injection wells as the pressure gradient from injection becomes less influential on flow processes. Flow regimes ranging from compact flow to capillary channel flow or secondary accumulation beneath a seal are possible through time as the CO₂ plume travels through the storage reservoir. Here we model the range of possible migration behavior in the capillary channel regime in small-scale domains whose heterogeneity has been resolved at depositional (sub-millimeter) scale. Two types of model domains have been studied in this work: domains with depositional fabric from real, naturally-occurring geologic samples and geostatistically generated synthetic model fabrics. The real domains come from quasi-2D physical geologic samples (peel # 1: ~1 m × 0.5 m sample and peel # 2: ~0.4 m × 0.6 m sample) that are vertically oriented relief peels of fluvial sediment extracted from the Brazos River, Texas. Peel # 1 is oriented perpendicular to dominant depositional flow while peel # 2 is a flow-parallel specimen. The various depositional fabrics represent definite correlation lengths of threshold pressures in the horizontal and vertical directions which can be extracted. High-resolution (~2 million element model) laser scanning of the samples provided detailed topography which is the result of nearly linear corresponding changes in measured grain size (normal distribution) and sorting. We model the basic physics of buoyant migration in heterogeneous domain using commercial software which applies the principle of invasion percolation (IP). The criterion for governing drainage at the pore scale is that the capillary pressure of the fluid needs to be greater than or equal to the threshold pressure of the pore throat it is trying to enter for the interface to advance into the pore. Here we employ the extension of this concept to flows at larger scales, which replaces the pore throat with a volume of rock with a characteristic value of capillary entry pressure. The fluid capillary pressure is proportional to the height of continuous column of the buoyant phase. The effects of (i) threshold pressure range, i.e. difference between the maximum and minimum threshold pressures in the domain; and (ii) the density difference between CO₂ and connate water on capillary channels of CO₂ were studied on the various sedimentologic fabrics. As the rock and fluid properties varied for different model domains, ₂ migration patterns varied between predominantly fingering and predominantly back-filling structures. Sufficiently heterogeneous media (threshold pressures varying by a factor of 10 or more) and media with depositional fabrics having high ratios of horizontal and vertical correlation lengths of capillary entry pressures in the domain yield back-filling pattern, resulting in a significantly large storage capacity. Invasion percolation simulation models give qualitatively similar CO₂ migration patterns compared to full-physics simulators in small-scale but high resolution domains which are sufficiently heterogeneous. On the other hand, we find the invasion percolation simulations predicting disperse capillary fingering pattern in relatively homogeneous media (threshold pressures varying by less than a factor of 10) while the full-physics simulations reveal a very compact CO₂ front in the same media. This stark difference needs to be investigated to understand the governing flow physics in these domains. Fingering flow pattern in the capillary channel regime would clearly result in the estimated storage capacity being much less than the nominal value (the pore volume of the rock) as the rock-fluid contact is minimal. The importance of this work lies in the verification that a relatively simple model (invasion percolation), which runs in a very small fraction of the time required by full-physics simulators, can be used to study buoyant migration in rocks at the micro-scale. Understanding migration behavior at the small-scale can help us approach the problem of upscaling better and hence define the complex plume dynamics at the reservoir scale more realistically. Knowledge of the correlation structure of the sedimentologic fabric (ratio of correlation lengths of threshold pressures in horizontal and vertical directions) and the threshold pressure distribution (permeability distribution) for any given reservoir rock could help evaluate amount of CO₂ that can be stored per unit volume of rock (storage potential) for a reservoir in the migration phase of sequestration. The possibility of predictive ability for expected capillary channel flow patterns kindles the prospect of enabling an engineered storage strategy that drives the behavior toward the desired flow patterns in the subsurface. / text