Electronic Theses and Dissertations (2010 - Present)

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The University of Houston Libraries collect and make publicly available all electronic theses and dissertations (ETDs) produced in UH graduate and PhD programs through the UH institutional repository. ETDs become available after the student submits them to the UH Graduate School, the document is approved by all appropriate parties, and any embargo on the document expires.

Collection Scope

UH Libraries began publishing ETDs from several UH Colleges in 2010. As of Summer 2014, all UH Colleges that require a thesis or dissertation for graduation began submitting these documents in electronic format. Below is a list of UH Colleges that currently participate in the ETD program and their coverage dates in this repository.

UH College	Coverage Dates
C.T. Bauer College of Business	2010-Present
Cullen College of Engineering	2012-Present
Conrad N. Hilton College of Hotel and Restaurant Management	2015-Present
College of Education	2010-Present
College of Liberal Arts and Social Sciences	2012-Present
College of Natural Sciences and Mathematics	2012-Present
College of Optometry	2010-Present
College of Pharmacy	2010-Present
College of Technology	2012-Present
K. G. McGovern College of the Arts	2016-Present
G. D. Hines College of Architecture & Design	2016-Present
Graduate College of Social Work	2012-Present

Additional Information

Online access for content outside these coverage dates may be available electronically through ProQuest.
Note: As of Fall 2017, all theses and dissertations produced at UH will be submitted to ProQuest. Additionally, some UH Colleges have contributed content to ProQuest at different periods of time in the past.
For print theses and dissertations found outside these coverage dates, please consult UH Libraries’ catalog.
Additional information on submitting ETDs can be found at the UH Graduate School.

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1,3-Dipolar and 1,3,6-Tripolar Reactivity of 3-hydroxy- and 3-amino-1-N-arylazopropenes for Heterocycle Formation
(2019-12) Bolinger, Andrew Arch 1989-; May, Jeremy A.; Coltart, Don M.; Teets, Thomas S.; Do, Loi H.; Gilbertson, Scott R.; Cirino, Patrick C.
3-Alkoxy-1-N-aryl azopropene structural motifs in the Eschenmoser-Tanabe Fragmentation pathway have been known for almost 50 years, yet one unexploited feature of these intermediates is their putative 1,3-dipole. Described here is a transformation leveraging this reactivity to synthesize an important class of oxygen heterocycles, β,γ-fused bicyclic γ-lactones, by the simple combination of an ester or acyl pyrrole, an α-epoxy-2-nitrophenyl hydrazone, and a base. The products of this reaction, including those containing quaternary centers, are generated with high (up to >25:1) diastereoselectivity. Conveniently, both syn- and anti-fused bicyclic systems can be generated stereoselectively by simply changing the counter-ion of the base, LiHMDS and KHMDS, respectively. This dissertation also describes the development of a new functional group, 3-amino-1-azopropene, and its use in novel annulation strategies leading to N-heterocycles, which are important structures found in drugs and biologically active natural products. The 3-amino-1-azopropene functional group possesses multiple nucleophilic sites and, as such, is expected to inspire the development of a wide range of new synthetic methods and/or find applications in the development of new drugs and materials. Lastly, as part of the continuing effects to develop new reactions for the formation of saturated heterocycles, the conjugated π systems of azoalkenes in 3-hydroxy-azopropenes and 3-amino-1-azopropene were utilized in a [4+2] cyclization reaction in order to achieve ring closure. Compounds were prepared in high (up to >25:1) diastereoselectivity from a cascading Tsuji-Trost [4+2] cycloaddition, producing a wide array of fused tetrahydrofuran- and pyrrolidine- tetrahydropyridazine derivatives.
1,4–Conjugate Addition with Pyrrole and Indole Enones & Propargylic Substitution using Boronic Acids as Nucleophiles with Gallium and Silver Catalysts
(2021-08) Boylan, Amy; May, Jeremy A.; Gilbertson, Scott R.; Cuny, Gregory D.; Miljanić, Ognjen Š.; Guloy, Arnold M.
This dissertation covers two projects: 1,4–conjugate addition on pyrrole and indole enones, and propargylic substitution using boronic acid as nucleophiles and silver/gallium catalysts. b-(2-indole)-enones and b-(2-pyrrole)-enones, both historically problematic substrate types with 1,4–conjugate addition reactions, were extensively examined. Analysis of isomer- related reaction rate trends showed that proximity of a heteroatom to the enone b-carbon was favorable to reaction rate and increased resonance electron donation also increased reaction rate. These enantioselective conjugate addition reaction were ultimately enhanced by using a less electron deficient catalyst and a base additive, ammonium carbonate. After many reactions and substrates were studied, this base was shown to have an advantage effect on enhancing the conjugate addition reaction but had an adverse effect on the starting material, which lead to other side reactions with this conflicted system. For the second project, three methods have been developed for nucleophilic propargylic substitutions that have been useful in forming tertiary carbons: (IPr)GaCl3/AgSbF6 with boronic acid at 23°C, AgSbF6 with boronic acid at 40°C, and GaCl3 with boronic acid at -78°C. A combination of AgSbF6 and IPrGaCl3 along with boronic acids at lower temperatures have been shown to decrease reaction times for the formation of nucleophilic substitution through the displacement of propargylic alcohols. GaCl3 with boronic acid at -78°C proved to be the best conditions for the formation of the quaternary carbon centers. An expanded substrate scope and nucleophile scope have been developed for the formation of the tertiary carbon centers and quaternary carbon centers using these three method
1. Attempts to Prepare Porous Materials Based on Thiols and Fluorinated Precursors 2. Self-Sorting of Complex Libraries during Kinetically Controlled Acylations
(2015-08) Liang, Xiao 1990-; Miljanić, Ognjen Š.; Cai, Chengzhi; Coltart, Don M.; Xu, Shoujun; Conrad, Jacinta C.
This thesis presents three studies in supramolecular chemistry. First is the synthesis and characterization of dynamic covalent disulfide bond based metal-organic framework (MOF), second is development of the fluorinated and imine-based non-covalent organic framework (nCOF), and the third is of molecular recognition between nucleophiles and acyl chlorides. Chapter One follows the ligand design and post-synthetic tailoring as the two most important strategies in synthesizing new metal-organic frameworks (MOFs). Organic dynamic covalent ligand 4,4’-dithiobisbenzoic acid (DTBA) was designed to synthesize a new MOF with metal Cu. These new Cu-DTBA MOF crystals were then tested by reduction on reversible disulfide moieties in the organic ligand but the resulting product could not be further recrystallized. Cu-DTBA templated inter-molecular self-sorting between two disulfide ligands could be achieved successfully, but intra-molecular self-sorting from the single cross-linked disulfide ligand produced a different type of material which did not show the exchangability of disulfide bonds. Chapter Two shows the development of the nCOFs’ structures based on the previous trispyrazole nCOF studies. The necessity of the terminal pyrazole and its trigonal ligand topology were confirmed by synthesizing and characterizing the following two nCOFs. Partially fluorinated trisphenyl nCOF replaced the terminal pyrazole by phenyl ring, which eliminated the hydrogen bonding, as well as linear imine-based nCOF which formed a different topology. The single crystal X-ray result of the two showed a three-dimensional infinite network structure, but with very little voids that cannot be useful as porous solids. Chapter Three introduces the simultaneous ordering and categorizing processes, i.e., self-sorting, which can occur under both thermodynamic and kinetic control. Thermodynamically controlled self-sorting phenomena widely exist in nature, while kinetically controlled self-sorting usually requires stimuli to help simplify the complex. Therefore, acylations between nucleophiles and acyl chlorides as fully kinetically controlled self-sorting systems were conducted. A series of [2×2] systems was conducted in order to find reactivity differences among nucleophiles as well as acyl chlorides. Furthermore, nine successful [3×3] systems achieved successful self-sorting with high selectivity.
1. C-C Bond Formation via Soft Enolization and Umpolung-like Chemistry 2. Electrophilic Fluorination of Organozinc Reagents
(2020-12) Aderibigbe, Sabrina Olunike Wande; Daugulis, Olafs; May, Jeremy A.; Gilbertson, Scott R.; Chen, Tai-Yen; Ozerov, Oleg V.
Synthetic methodology development towards convenient C-C bond and C-F bond formation is a desirable synthetic tool for industry and academia. Using commercially available substrates towards chemical transformations is often a strategy used to simplify the process of synthesizing compounds. This dissertation focuses on the synthetic methodology development of C-C and C-F bond formation for broad applicational utility. This dissertation will discuss two synthetic strategies towards C-C bond formation, soft enolization and Umpolung-like chemistry. The direct synthesis of 1,3-diketones and β-keto thioesters using in good yields and with wide substrate tolerance was possible using our soft enolization strategy using crude acyl chlorides. Another C-C bond strategy explored was an Umpolung-like approach towards α-functionalization of ketones. Ketones are synthetically important functional group and have wide applicational uses within chemistry and biology. The α-functionalization of ketones and their derivatives via addition of their corresponding (aza) enolates to alkyl halides is a fundamental synthetic transformation but has been historically less explored despite its potential widespread utility. Our approach towards uses a novel β-silylated azoalkenes intermediate towards anti-diastereoselective α-alkylation of ketones. In addition, we explored a streamlined approach towards monofluorohydrocarbon formation via electrophilic fluorination of organozinc compounds. We hope this will have wide applicational utility as C-F bonds are important within agrochemistry and pharmaceutical chemistry.
1. SELF-SORTING OF DYNAMIC IMINE LIBRARIES UNDER CHEMICAL AND PHYSICAL STIMULI; 2. CHARACTERIZATION OF POROUS MATERIALS BASED ON A FLUORINATED TETRAZOLE
(2016-05) Hsu, Chia-Wei 1984-; Miljanić, Ognjen Š.; Daugulis, Olafs; Baldelli, Steven; Cuny, Gregory D.; Thummel, Randolph P.
Chapter 1 introduces the self-sorting processes of dynamic combinaotrial libraries (DCLs) under thermodynamic and kinetic control. Based on the concept of dynamic combinatorial chemistry (DCC), disulfide exchange, imino bond formation, transesterification, and metal-ligand interaction are widely utilized to perform the re-equilibration of molecules. Simplification of multicomponent systems and the manipulation toward the direction of equilibrium are reviewed. Chapter 2 of this dissertation describes an application of a new external stimulus—adsorption on the silica gel surface—to dynamic imine libraries constructed of as many as four aldehydes and four anilines. During the elution process, imines keep trading their components, resulting in the amplification of the least polar imine which travels down the silica gel-based column the fastest. This process is then iteratively repeated to isolate the next least-polar component in the remaining imine library, eventually simplifying the library from n2 into n members. In Chapter 3, we demonstrated iterative simplification of a dynamic imine library constructed from 10 aldehydes and 10 anilines using three orthogonal external stimuli. First, mild oxidation (using molecular iodine as an oxidant) was applied to oxidize the most electron rich imine with the rapid imine exchange. In the second self-sorting step, we obtained a halogenated [2×2] sub-system with bromo- and chloro-substituted imines from the imine library. Third and final step was a slow distillation of the residual imines from the column, leading to the amplification of the least volatile imine in 61% yield. Ultimately, this [10×10] imine library is simplified into two major products and one sub-system after iterative self-sorting. Chapter 4 will describe the synthesis and characterization of a porous material based on an extensively fluorinated aromatic tristetrazole. This molecule crystallizes in a porous structure which is held together through [N−H…H] hydrogen bonds and electrostatic interactions between C–F units in these molecules. This porous material is compositionally stable up to 270 °C and shows selective adsorption of CO2 over N2 (15:1 in mmol g−1) at 195 K and 760 mmHg.
1. Synthesis of New Polyfluoroaryl Materials. 2. New Transition Metal Catalysts for Enantioselective C – H Bond Functionalization.
(2021-12) Lieu, Thien Ngoc; Daugulis, Olafs; Miljanić, Ognjen Š.; Wu, Judy I-Chia; Teets, Thomas S.; Rimer, Jeffrey D.
1. Synthesis of new polyfluoroaryl materials. Polyfluorinated porous materials are essential in sequestration of fluorine pollutants due to their high water resistance and fluorophilic ability. In 2014, our and Dr. Miljanic group introduced a triangular porous material prepared from perfluoro organic compounds, showing remarkably selective adsorption toward halogenated hydrocarbons. Based on the precedent published in 2014, we attempted to increase the pore size of this material by inserting 2,2’-bipyridine groups on each linkage arm. Furthermore, modification of central arene groups was accomplished by using 1,3,5-triazine or 1,3,5-trifluorobenzene. In addition, ferrocene based fluorine material and two tetragonal fluorine compounds containing pyrene and tetraphenylethylene core were successfully synthesized by using copper catalysis as a main step. Among these compounds, tetraphenylethylene-based structure showed different emissive behaviors under ‘wet’ and ‘dry’ conditions. Other fluorinated tetraphenylethylene compounds such as (Z)/(E)-bis(pentafluorophenyl)stilbene, and tris(pentafluorophenyl)ethylene were synthesized using copper catalysis. In addition, their reactivity and selectivity in photocyclization reactions was also explored. 2. New transition metal catalysts for enantioselective C – H bond functionalization. Enantioselective carbon-hydrogen bond functionalization using transition metal catalysis is one of the most powerful tools in organic synthesis. This method offers a straightforward route to obtain enantiopure isomer compounds. Thus, in the second part of this dissertation, two new types of potential chiral catalysts were developed and their reactivity was explored. A series of new C3-symmetric tridentate sulfur-containing ligands were synthesized. Various transition metals such as rhodium, iridium, ruthenium, and copper were coordinated to these ligands. In addition, catalytic activity of copper(I) and ruthenium (II) complexes was proved in carbene and nitrene C-H insertion reactions. Finally, aminoquinoline-directed enantioselective coupling of sp2 C-H bonds with alkenes using new cobalt catalyst was explored. The catalyst tolerates a broad substrates scope such as styrenes and aliphatic alkenes, giving low to medium level of enantioselectivity. This result may open an opportunity in asymmetric functionalization using bidentate directing groups, which sp far has proven very difficult.
2-D Deformable-layer Tomostatics in Sichuan, China
(2015-08) Wo, Yukai 1991-; Zhou, Hua-Wei; Hall, Stuart A.; Lau, August
Static correction for near-surface effects is a critical issue for onshore seismic data processing due to its significant impact on imaging the subsurface structure, especially for area with severe topographic and near-surface velocity variations. The key idea to determine static correction is to build an accurate near-surface velocity model, which leads to several methods such as refraction statics, uphole surveys and tomostatics. Among these methods, tomostatics, which builds the near-surface velocity models using tomography, is a promising method. However, in complex near-surface areas, traditional grid tomography is often unable to determine the static correction. This is mainly because the conflict between the need of smaller cell to describe the severe velocity variation and the increasing number of inversion unknowns which leads to solution's uncertainty. The deformable-layer tomography (DLT) determines the complex near-surface velocity models by inverting for depth-varying velocity interfaces. Both synthetic and field data offer many cases illustrating DLT's effectiveness. The main advantage of DLT over grid tomography is that DLT builds a geologically reasonable model with less inversion unknowns, and can resolve the velocity model better with some constrains such as the result of uphole surveys, which is available in my study. Also, a reversed-velocity interface, which is common in mountainous area and has severe effect on near-surface imaging, may be better solved by DLT. The survey area of my thesis is in the western Sichuan, China, which is mountainous and has a complex near-surface situation. Thus, I have been motivated to find whether the DLT can be a good solution to this problem. I use the DLT to build the near-surface velocity model and determine the static correction for the area. The final velocity model produced by DLT holds close velocity-depth information compared to uphole survey, and static correction calculated from such model shows improvement, such as an increasing level of reflection coherency on stack section.
2-d Di-hadron Correlations at √sN N = 2.76 TeV using the ALICE experiment
(2015-05) Piyarathna, Danthasinghe Waduge Badrajee 1983-; Bellwied, Rene; Bassler, Kevin E.; Hungerford, Ed V.; Pinsky, Lawrence S.; Bittner, Eric R.
The Large Hadron Collider (LHC) at CERN Geneva, Switzerland, attempts to recre- ate the initial conditions at the begining of our universe. Heavy ions ( Pb208) are accelerated up to 0.999999 of the speed of the light and collided at √sN N = 2.76 T eV (center of mass energy per nucleon) in order to recreate the initial energy density (∼ 10−6s) after the Big Bang. The theory of Quantum Chromo Dynamics (QCD) predicts the formation of a primordial nuclear matter phase known as Quark Gluon Plasma (QGP) under these experimental conditions. This dissertation focuses on studying this QCD medium using data from the ‘A Large Ion Collider Experiment’ (ALICE). The study of two-dimensional two-particle correlations of emitted charged par- ticles carries valuable time integrated information of the dynamical QCD medium. Long-range correlations between particles in angular and momentum space generally can be attributed to collective behavior, which is not found in a superposition of elementary collisions. The focus of this thesis is to understand the long-range corre- lation structure observed in pseudo-rapidity (∆η) as a function of pT and to obtain better estimates of medium properties of the QGP, such as shear viscosity. The inter- pretation is based on empirical models describing well-established hydrodynamical collective flow phenomena and possible novel phenomena related to in-medium par- ton fragmentation. The flow and Gaussian parameters extracted from the fit model can be used to constrain medium properties such as the initial gluon density, the shear viscosity and the partonic energy transport coefficient.
2020 Vision: An Interpretative Phenomenological Analysis of the Lived Experiences of Black Female Athletes
(2021-05) Shaw, Aquasia Audre; Hawkins, Billy J.; Ogunrinde, Joyce Olushola; Cottingham, Michael; Lee, Mimi Miyoung
This study sought to understand the experiences of Black female athletes and their perspective amid a global pandemic, political protests, social unrest, and calls for justice after the deaths of several unarmed Black people by law enforcement. Employing critical race feminism and colorblind ideology, this interpretative phenomenological analysis qualitatively observed influential factors for Black female athletes and examined the effects race, gender, and sport (or the intersection of all three) had on the experiences of Black female athletes during an extraordinary time. Eight Black female collegiate and semi-professional athletes completed reflexive journals and semi-structured interviews, revealing ways they negotiated their personal and athletic environments, and leveraged their autonomy. Four themes emerged from the data: (a) identity and growth; (b) navigating athletics; (c) hypervigilance; and (d) influencers and motivational factors. This study adds to the scarcity of research on Black female athletes and the way they are affected emotionally, socially, and politically and the strategies they use to cope, manage, and survive. Findings demonstrate the problematizing nature of bias, racism, and discrimination within athletics, and the techniques Black women use to navigate spaces that are not conducive to their needs. Future research is also discussed as the study developed new knowledge in the ways Black women in sport would like to be supported.
2d DI-HADRON CORRELATION AT √SNN = 200 GeV USING THE STAR EXPERIMENT
(2012-12) De Silva, Lindamulage 1980-; Bellwied, Rene; Pinsky, Lawrence S.; Hungerford, Ed V.; Kouri, Donald J.; Ordonez, Carlos
The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Lab (BNL) in Long Island, New York, attempts to recreate the initial conditions at the birth of our universe. Heavy Au ions are accelerated up to 0.99995c and collided at √SNN = 200 GeV (center of mass energy per nucleon) in order to recreate the initial moments (~10−6s) after the Big Bang. The theory of Quantum Chromo Dynamics (QCD) predicts the formation of a primordial nuclear matter phase know as Quark Gluon Plasma (QGP) under these experimental conditions. This dissertation focuses on studying this QCD medium using data from the Solenoidal Tracker At RHIC (STAR) detector. The study of two-dimensional two-particle correlations of emitted charged parti- cles contains valuable time integrated information of the dynamical QCD medium. Long range correlations between particles in angular and momentum space generally can be attributed to collective behavior not found in a superposition of elementary collisions. The focus of this thesis is to understand a novel, long-range correlation structure observed in pseudo-rapidity (∆η) as a function of . Data from √SNN = 200 GeV AuAu collisions are confronted with CuCu and pp collisions at the same energy to establish system size dependence. The interpretation is based on empirical models describing well established hydrodynamical collective flow phenomena and possible novel phenomena related to in medium parton fragmentation. The param- eters extracted from the model fit can be used to constrain medium properties such as the initial gluon density, the shear viscosity and the partonic energy transport coefficient.
3-D Plasmonic Nanoarchitectures: Fabrication, Characterization, and Applications
(2017-12) Arnob, Md Masud Parvez; Shih, Wei-Chuan; Wolfe, John C.; Zagozdzon-Wosik, Wanda; Chen, Ji; Chu, Wei-Kan; Chen, Tai-Yen
Plasmonic nanostructures are known to concentrate incident light to their surfaces by collective electron oscillation, a.k.a., localized surface plasmon resonance (LSPR). Plasmonic hot-spot refers to locations where electromagnetic fields are particularly enhanced relative to the incident field. Traditional plasmonic nanomaterials are 1D (e.g., colloidal nanoparticles) or 2D (lithographically patterned nanostructure arrays) in nature, which typically result in sparse field concentration patterns. To improve efficiency and better utilization of hot-spots, 3D plasmonic nanoarchitectures are desired, where abundant hot-spots are formed in a 3D volumetric fashion, a feature drastically departing from traditional nanostructures. In this dissertation, two novel 3D plasmonic nanostructures are reported. The first one is NPG nanoparticle, a disk shaped nanostructure with 3D pore-ligament bi-continuous network. NPG disks are made by the low-cost nanosphere lithography (NSL) technique, which is capable of wafer scale production. NPG disks possess larger surface area and high density internal plasmonic hot-spots, which are absent in its bulk counterparts. Due to these unique properties, NPG disks can be potentially used in various surface enhanced Raman spectroscopy (SERS), surface enhanced fluorescence (SEF), and photothermal based applications. To optimize the performance of NPG disks in various applications and understand its plasmonics better, two different modeling techniques, Bruggeman effective medium theory (B-EMT) model and Nanoporous (NP) model, are introduced and evaluated against the experimental data obtained by an electron beam lithography (EBL) compatible fabrication technique for NPG disks. The EBL method can provide large area 2D patterns of randomly distributed nanodisks with flexible interdisk (center to center) distance. Such flexibility is essential to obtain quasi-single NPG disk response, which typically peaks in the near infrared (NIR) spectrum beyond 1 μm, from ensemble measurements by common UV/VIS/NIR spectrometers instead of a specialized NIR spectroscopic microscope. After successful fabrication and modeling, the plasmon enhanced catalysis application of NPG disks is reported in details. The effectiveness of NPG disks in various applications depends on its LSPR peak position. Hence, optimization of an application might require the fine tuning of the peak position. A novel laser based rapid thermal annealing technique is reported to fine tune the LSPR peak position of NPG disks. The second 3D plasmonic nanostructure, reported in this dissertation, is based on the chicken egg shell, a day-to-day waste material. The 3-dimensional (3D) submicron features on the outer shell (OS), inner shell (IS), and shell membrane (SM) regions are sputter coated with gold found to have excellent SERS performance. Moreover, the outer shell substrate is found to be capable of detecting single bacterial cell. This facile way of fabricating 3D plasmonic substrates can facilitate the adoption of 3D plasmonic substrates by researchers in less fortunate countries.
3-D SEISMIC SURVEY DESIGN VIA MODELING AND REVERSE TIME MIGRATION: PIERCE JUNCTION SALT DOME, TEXAS
(2014-05) Coskun, Suleyman 1984-; Stewart, Robert R.; Khan, Shuhab D.; Baysal, Edip
Seismic forward modeling studies are required for adequately imaging complex geological structures, such as folds, faults, and domes. Many U.S. Gulf Coast salt domes are used for oil and gas exploration, brine production, and underground hydrocarbon storage. For this reason, it is crucial to image the flank of the salt domes and surrounding sediments. Allied Geophysical Laboratories (AGL) carried out a 2-D seismic study in the Texas Brine Company facility to image the Pierce Junction salt dome. However, we were not able to image the salt flanks because of improper survey design. This led to the current study which proposes a 2-D and a 3-D seismic survey design using modeling and Reverse Time Migration (RTM) imaging. We gathered original 2-D seismic, topography, and gravity data to build 2-D and 3-D velocity models of the Pierce Junction salt dome area. We processed the original 2-D data and extracted the velocities of the cap rock and near surface sediments for use in velocity models. We modelled gravity data collected in a north-south direction and performed analyses on the synthetic seismic data to determine new 2-D conventional seismic survey parameters that could be achieved with the limited acquisition equipment of AGL. We modeled synthetic shot gathers by a finite difference method using the full (two-way) acoustic wave equation, and generated seismic images using the Reverse Time Migration (RTM) method. We determined the optimum parameters of the new 2-D seismic survey by reviewing the quality of the results. These parameters were able to adequately image the salt dome and its surrounding sediments. We then modified the 2-D parameters for a new 3-D survey, and obtained synthetic RTM images based on the 3-D velocity model. Optimal 2-D and 3-D seismic survey designs for the Pierce Junction salt dome area were achieved using seismic modeling and RTM imaging. We found RTM imaging to be a novel and powerful method for determining seismic survey parameters for complex geological structures.
3D Allostratigraphic Mapping and Facies Heterogeneity of a Compound Tributary Incised Valley System, Turonian Ferron Sandstone, Notom Delta, South-Central Utah
(2013-05) Hilton, Benjamin David 1985-; Bhattacharya, Janok P.; Khan, Shuhab D.; Cleveland, David M.
Incised valley systems are important for sequence stratigraphic and exploration purposes. The tributary component of these systems may inherit complicated, self-similar, plan-view morphologies from the drainage networks that form them. Incised valley depositional models often exclusively focus on fill facies within trunk valleys and either ignore or poorly document facies within tributary valleys. The Notom Fluvio-Deltaic complex, a component of the Turonian (Late Cretaceous) Ferron Sandstone Member of the Mancos Shale Formation, outcrops along Neilson Wash, Utah, and provides the opportunity to study in 3D, facies heterogeneity of compound incised valley fills, including both trunk and tributary components. Using traditional field methodologies (56 measured sections) and remote sensing (aerial LiDAR survey), several objectives have been completed: 1) previous 2D outcrop work / interpretations have been updated and described in 3D space using allostratigraphic principles; 2) Isopach maps and paleogeographic reconstructions show north-east oriented channel belts with both braided and meandering plan view patterns within their respective valley fills; 3) younger cut and fill sequences (unaccounted for in previous studies) are documented; and 4) Interpretation of remnant terraces / interfluves suggest high diachroneity associated with the higher and lower order erosion surfaces that form the composite sequence boundary. Valley allomembers V2B and V2A are shown to be tributary in nature compared with larger or trunk valley allomembers based on stratigraphic valley width to thickness ratio’s, grain size differences, scale of sedimentary structures, preserved thickness of channel elements and abundance of facies types. Confined valleys appear more sand dominated while less confined to unconfined valleys preserve significant floodplain facies, as predicted by traditional incised valley models. Tributary fills appear linked to valley-specific hydrologic conditions, distance to estuarine/tidal processes, river style (braided or meandering), and sediment supply. This outcrop-based study gives a less common 3-dimensional insight to the evolution of a compound incised valley system, which may prove useful for subsurface exploration and for the advancement of oversimplified incised valley facies models.
3D Crustal Modeling of the Barreirinhas and Ceara Basins of Northeastern Brazil
(2019-05) Lunn, Eric M. 1993-; Wu, Jonny; Bird, Dale E.; Mann, Paul; Krueger, Ana
The Barreirinhas and Ceara Basins, offshore northeastern Brazil, cover a combined area of approximately 105,000 km^2 and formed north and south of the Romanche Fracture Zone (RFZ) respectively. The RFZ is a 4,500 km-long, 10-40 km-wide oceanic fracture zone that extends from offshore northeastern Brazil to offshore Ghana-Togo/Benin. During Aptian times, northeastern Brazil rifted from the continental margin of West Africa. Questions remain regarding northeastern Brazil’s crustal structure, its reconstructed fit with NW Africa, and its exploration potential. To address these questions, a 3D model was created by integrating industry quality 2D seismic reflection and well log data with open-file gravity, sediment thickness, topography, and seismic refraction data (including wide-angle lines and individual stations). Additionally, a sediment thickness grid was produced by interpreting 13,171 km of modern 2D seismic profiles to constrain the inversion. The Barreirinhas and Ceara basins 3D model was constructed with five horizons, which separated six layers: air, water, sedimentary rocks, upper crystalline crust, lower crystalline crust, and upper mantle. A 3D gravity structural inversion on the Moho horizon was performed, the total thickness of the crystalline crust based on the new Moho horizon was calculated, and a continent-ocean transition zone (COTZ) based on the new crustal thickness was defined. The width of the transition zone in the Barreirinhas basin ranged from 5 to 25 km and in the Ceara from 5 to 100 km. Landward of the COTZ, the continental crust thickness ranged from 14 km near the COTZ to 40 km, whereas seaward of the COTZ, the oceanic crust thickness ranged from 5 to 10 km. These thicknesses support the idea that the equatorial South Atlantic Ocean opened as a series of right-lateral, pull-apart basins with varying degrees of obliquity to the South Atlantic opening direction. The Romanche Fracture Zone does not extend as far west as previously thought, but appears to have formed in-line with intracontinental pre-existing zones of weakness. The new sediment thickness map better defines the major depocenters offshore equatorial Brazil while the model-derived crustal thickness map and COTZ, may provide insights for source rock maturity within the Barreirinhas and Ceara basins.
3D facial modeling with geometric wrinkles from images
(2023-04-27) Deng, Qixin; Deng, Zhigang; Pavlidis, Ioannis T.; Chen, Guoning; Mayerich, David
Realistic 3D facial modeling and reconstruction have been increasingly used in many graphics, animation, and virtual reality applications. Currently many existing face models are not able to present rich details while deforming, which means lack of wrinkles while face shows different expressions. Also, to create a realistic face model for an individual is also needs complex setup and sophisticated works from experienced artists. The goal of this dissertation is to achieve an end-to-end system to augment coarse-scale 3D face models, and to reconstruct realistic face from in-the-wild images. I propose an end-to-end method to automatically augment coarse-scale 3D faces with synthesized fine scale geometric wrinkles. I define the wrinkle as the displacement value along the vertex normal direction, and save it as displacement map. The distribution of wrinkles has some spatial characteristics, and deep convolutional neural network (DCNN) is pretty good at learning spacial information across image-format data. I labeled the wrinkle data with its identity and expression vectors. By formulating the wrinkle generation problem as a supervised generation task, I implicitly model the continuous space of face wrinkles via a compact generative model, such that plausible face wrinkles can be generated through effective sampling and interpolation in the space. Then I introduce a complete pipeline to transfer the synthesized wrinkles between faces with different shapes and topologies. The method can augment an exist 3D face model with more fine-scale details, but to create a realistic human face model is not yet solved. Properly modeling complex lighting effects in reality, including specular lighting, shadows, and occlusions, from a single in-the-wild face image is still considered as a widely open research challenge. To reconstruct an realistic face model from an unconstrained image, I propose a CNN based framework to regress the face model from a single image in the wild. I designed novel hybrid loss functions to disentangle face shape identities, expressions, poses, albedos, and lighting. The outputted face model includes dense 3D shape, head pose, expression, diffuse albedo, specular albedo, and the corresponding lighting conditions.
3D Finite-Difference Based Electromagnetic Modelling Multidisciplinary Applications
(2020-05) Yu, Mengping; Chen, Ji; Jackson, David R.; Chen, Jiefu; Benhaddou, Driss; Kaula, Norbert
This dissertation mainly focused on the multidisciplinary applications of a 3D finite-difference based electromagnetic modeling which included applications in oil & gas industry as well as medical industry. For applications in oil & gas industry, we focused on the electromagnetic modeling aspect of the digital rock physics (DRP) to understand the relationship between the micro-structures and contents within the structure to their electrical properties. This is achieved via using the 3D rock micro-CT images and performing electromagnetic modeling using the 3D numerical mixing law (finite difference method based), which is a robust numerical method with high efficiency. Based on the results of this investigation, one can establish the relationship between the rock structure/porous space filling materials and the buck electrical properties, such as the permittivity and the conductivity. Additionally, conventional methods to extract the electrical properties from Micro-CT rock images require significant computational resources. This thesis also includes a novel multi-scale method for such large-scale modeling based on a hierarchy approach. Without losing any information from the original Micro-CT images, the method uses the mixing theory to extract equivalent rock electrical properties at multi-level and cascades all results at different level to achieve the overall rock properties. The method proposed in this application effectively overcome previous approximation that needs to decimate the original images and all vital information will be remained. Modelling and simulations are performed at multi-scale with different choices of sub model sizes to understand the effect of partition on the overall accuracy. For the application in medical industry, we focused on the spinal cord stimulation. Spinal cord stimulation (SCS) is a type of neuro-stimulation therapy proven to be effective for many chronic pain suffers; it helps mask pain by blocking or modifying pain signals before they reach the brain. The main purpose of this research is to evaluate the dorsal column (DC) activation region that relate to dermatomal coverage. A paddle lead with 4×5 contact array was utilized to achieve expected coverage of DC fibers. An efficient 3D finite-difference-based method was applied to obtain the field potentials inside the spinal cord, which can be coupled to the second step biophysical mammalian myelinated fiber model to identify the DC activation region.
3D GROUND-PENETRATING RADAR (GPR) INVESTIGATIONS: BURIED CULVERTS, HISTORICAL GRAVES, A SANDSTONE RESERVOIR ANALOG, AND AN IMPACT CRATER
(2016-05) Aziz, Azie Sophia 1979-; Stewart, Robert R.; Khan, Shuhab D.; Wiley, Robert; Borgerson, Jacob
Ground-penetrating radar (GPR) is used to characterize a variety of subsurface targets such as buried culverts, historical graves, reservoir analogs, and impact craters. In the first case of “buried culverts” I evaluated the GPR performance across five antenna frequencies to determine which would best image buried culverts. Laboratory measurements of soil were made to provide independent measurements to compare measurements and estimates from the field experiments and other sources. Estimates of radar velocities for the set of GPR antenna frequencies were made by a variety of GPR processing techniques together with survey measurements. These velocities were then used in the imaging and time-to-depth conversion of the GPR data. The best velocity used for the various migrations showed a frequency dependence. In the second case of “historical graves” Terrestrial Laser Scanning (TLS) was used before GPR to provide an elevation map of the survey area. This map was analyzed to find anomalous mounds and depressions which provided leads to the location of undocumented graves that could be surveyed in depth with GPR for verification. In the third case of “reservoir analogs” I used 3D GPR to visualize the internal structure of terminal distributary mouth bars in the Cretaceous Ferron Sandstone in southeastern Utah. Three radar facies were observed including a terminal distributary channel of 1.25 m thickness filled with distributary mouth bars, a progradational mouth bar with a dip angle of approximately 20o, and a laterally continuous basal planar bed. GPR images revealed the geometry of architectural elements such as small-scale bedding (0.6 m) and the extent (9 m) of major bounding surfaces. In the fourth case of “craters” I used 3D GPR to image ejecta elements and to map the alluvium thickness at the Barringer (Meteor) Crater in Arizona. Some software was developed to assist the processing. Workflows were developed for TLS data and 3D GPR data. The results for all four cases were interpreted successfully and recommendations for future acquisition, processing, and interpretation were compiled. The wide range of imaging cases shows the usefulness of GPR in the imaging of buried culverts, historical graves, reservoir analogs, and impact craters.
3D Printing of Composite Organic Semiconductor Microdevices for Biosensors and Organic Bioelectronics
(2022-05-12) Dadras, Omid; Abidian, Mohammad Reza; Mohan, Chandra; Majd, Sheereen; Raghunathan, Vijaykrishna; Chen, Tai-Yen
Bioelectronic devices aim to alleviate symptoms or return function to patients suffering from neural disorders / injuries. Choice of functional material and employment of advanced fabrication techniques constitute key elements in ultimate success of these devices. As an alternative to traditional metallic platforms, organic electroactive materials have garnered tremendous attention in neural devices. Consequently, the emerging field of organic bioelectronics has sought to interface the organic-based devices with the soft and ion-dominated neural tissue. Organic semiconductor materials (OSs), i.e. conjugated polymers, have emerged as one of the ideal candidates for neural interfaces, owing to their biocompatibility, soft mechanical properties, and mixed electronic / ionic conductivity. This thesis is primarily focused on development of soft and conductive micron-scale platforms for applications in organic bioelectronics and biosensors. In the course of the projects, much attention has been devoted towards design of microelectronic devices, employing advanced fabrication techniques, and formulation of composite biomaterials based on two common OSs; poly(3,4-ethylenedioxythiophene) and polypyrrole. The theme of research projects falls into two main categories: 1. Soft and bioactive platforms for neural regeneration, and 2. 3D-printed conductive microelectronic devices for organic bioelectronics and biosensors. In the first category, we have developed a micro-patterning technique and have created various profiles of laminin gradients on surface of OS thin films, which can be potentially employed for neural regeneration. The second category deals with design, fabrication and characterization of 3D-printed microelectronic devices. First, we have explored 3D printing of soft, conductive, and bioactive microstructures via direct laser writing, also known as multi-photon polymerization lithography (MPL). We have formulated conductive photosensitive inks, and fabrication and characterization of microelectronic devices such as hybrid neural microelectrodes, bioactive microstructures and high-performance glucose biosensors have been successfully demonstrated. We also report on development of an in-house 3D printing technique for fabrication of OS microdevices based on in-situ electrochemical polymerization. Microelectronic devices, bioactive structures and glucose biosensors have been fabricated using this technique. Overall, we envision that these microelectronic devices and platforms pave the way towards development of next-generation neural interfaces for organic bioelectronics and biosensing applications.
3D Reconstruction of Tubular Structures Using MRI Projection Images
(2018-05) Unan, Mahmut 1986-; Tsekos, Nikolaos V.; Shah, Dipan J.; Leiss, Ernst L.; Shi, Weidong
After imaging information became available in digital form, techniques for acquiring volumetric data evolved. 3D reconstruction is mostly performed using multislice stack images. The objective of this dissertation is to introduce a simple magnetic resonance technique for imaging tubular structures, such as blood vessels and catheters, and 3D reconstruction of these structures. This study includes three major chapters: one on simulation and two on experiments with MRI projection images. First, a MATLAB simulation was created to analyze the reconstruction process; it was tested with different shapes of the structures and different numbers of projections. Second, triplanar projection imaging was evaluated on a phantom filled with a T1-shortening, Gd-based contrast agent embedded into a lipid matrix. The object is reconstructed from three mutually orthogonal projections of the volume that contain the structure of interest. The projected structures of the object were segmented out on each projection, back-projected to generate the segmented tubular object, and mesh-rendered in 3D. The accuracy of this approach was investigated by comparing the mesh-rendered tubular structure generated from projections with the mesh rendered from a multislice set of images of the same volume. Third, Inverse Radon Transform was implemented for 3D reconstruction of complex helical tubular structure from multiple radially deployed (oblique) projections. To compute the correctness of the 3D reconstruction processes, we compared the resulting meshes with the multislice-rendered meshes. Hausdorff distance and Point Cloud Comparison methods were used to evaluate the reconstruction error. The average error was less than 1 pixel for the triplanar projection images, and it was less than 2 pixels for the oblique orientation projection images. With further optimization and reduction of acquisition time, this method can be used for 3D fast imaging of interventional tools or segments of blood vessels with applications in interventional MRI.
3D SEISMIC GEOMORPHOLOGY AND SEISMIC STRATIGRAPHY OF LATE QUATERNARY SHELF AND SHELF -MARGIN DEPOSITIONAL SYSTEMS, NORTHERN GULF OF MEXICO
(2015-08) Lozano, Felipe A. 1973-; Wellner, Julia S.; Bhattacharya, Janok P.; Silva-Tamayo, Juan C.; Sager, William W.
Optimal exploitation of deltaic reservoirs needs detailed facies and architectural element analysis as a base for a comprehensive geological model. To date, very few studies have evaluated regional shelf-margin deltaic systems using 3D seismic data and 3D seismic geomorphologic and seismic stratigraphic analysis. High-resolution 3D seismic data, covering an area of 8,000 km2 offshore Louisiana at the modern shelf edge of the central northern Gulf of Mexico, was used to reconstruct the distribution and evolution of the paleo-Mississippi shelf-margin deltaic system during the last full cycle of fall and rise in sea level, which spans the last 125,000 years. Three-dimensional seismic geomorphological analysis was complemented with computed seismic attributes, including coherence, curvature, spectral components, sweetness, and amplitude gradient, with the objective of identifying shelf-margin geological features not typically observed in seismic profiles. The results show that salt tectonism in the Gulf of Mexico controlled the morphology of the shelf and the slope, forcing the paleo-Mississippi deltaic system to split, and concentrate its progradation and deposition in four separate along-strike salt-withdrawal minibasins. Each minibasin shows different deltaic constructional patterns. Progradation and aggradation patterns vary from minibasin to minibasin due to the response of the sediment supplied by the paleo-Mississippi delta, variations on sea level, the morphology of the seafloor, the arrival angle when the delta reaches the upper slope minibasin, and the shape of the minibasin. The 3D reconstruction of the system shows lateral variation of the deltaic processes from wave- to fluvial-dominated; wave-dominated deltaic strandplains were identified in the western minibasins and fluvial distributary channels were recognized in the eastern minibasins. This research highlights the importance of lowstand wave-dominated deltaic strandplains as important elements for the transport of sediment from the shelf to the slope in a salt-controlled setting like the Gulf of Mexico. The fluvial dominated shelf-margin delta is also related to direct transfer of sediment from the shelf to the slope

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