Engineering Commons^™

Improving Thermodynamic Consistency Among Vapor Pressure, Heat Of Vaporization, And Liquid And Ideal Gas Heat Capacities, Joseph Wallace Hogge

Theses and Dissertations

Vapor pressure (P_vap), heat of vaporization (ΔH_vap), liquid heat capacity (C_p^l), and ideal gas heat capacity (C_p^ig) are important properties for process design and optimization. This work focuses on improving the thermodynamic consistency and accuracy of the aforementioned properties since these can drastically affect the reliability, safety, and profitability of chemical processes. They can be measured for pure organic compounds from the triple point, through the normal boiling point, and up to the critical point. Additionally, ΔH_vap is proportional to the derivative of vapor …

A Molecular Simulation Study Of Antibody-Antigen Interactions On Surfaces For The Rational Design Of Next-Generation Antibody Microarrays, Derek B. Bush

Theses and Dissertations

Antibody microarrays constitute a next-generation sensing platform that has the potential to revolutionize the way that molecular detection is conducted in many scientific fields. Unfortunately, current technologies have not found mainstream use because of reliability problems that undermine trust in their results. Although several factors are involved, it is believed that undesirable protein interactions with the array surface are a fundamental source of problems where little detail about the molecular-level biophysics are known. A better understanding of antibody stability and antibody-antigen binding on the array surface is needed to improve microarray technology. Despite the availability of many laboratory methods for …

Effect Of Bioglass Incorporation Into Electrochemically Aligned Collagen Threads On Mechanical Properties And Cell-Mediated Mineralization, Madhura Nijsure

Theses and Dissertations

Bone related diseases and disorders are a significant socioeconomic burden in the United States. Autografts and allografts are most commonly used for the treatment of bone defects and non-unions; however, they are associated with limitations such as donor site morbidity and immune rejection, respectively. Over the past few decades, bone tissue engineering (BTE) using scaffold and cells has garnered significant interest as an alternative method for the repair and regeneration of bone defects. Recreation of the tissue microenvironment via the development of biomimetic scaffolds that resemble the physicochemical aspects (i.e., composition, topography, stiffness) of native bone is a promising approach …

Cell-Free Synthesis Of Proteins With Unnatural Amino Acids: Exploring Fitness Landscapes, Engineering Membrane Proteins And Expanding The Genetic Code, Song Min Schinn

Theses and Dissertations

Unnatural amino acids (uAA) expand the structural and functional possibilities of proteins. Numerous previous studies have demonstrated uAA as a powerful tool for protein engineering, but challenges also remain. Three notable such challenges include: (1) the fitness of uAA-incorporated proteins are difficult to predict and time-consuming to screen with conventional methods, (2) uAA incorporation in difficult-to-express proteins (e.g. membrane proteins such as G-protein coupled receptors) remain challenging, and (3) the incorporation of multiple types of uAA are still limited. In response, we pose cell-free protein synthesis (CFPS), a rapid and versatile in vitro expression system, as a platform to explore …

Particle Deposition Behavior From Coal-Derived Syngas In Gas Turbines At Modern Turbine Inlet Temperatures, Robert Laycock

Theses and Dissertations

Certain types of fuel used for combustion in land-based gas turbines can contain traces of ash when introduced into a gas turbine. Examples include synfuel, from the gasification of coal, and heavy fuel oil. When these ash particles travel through the hot gas path of the gas turbine they can deposit on turbine vanes and blades. As deposits grow, they can reduce turbine efficiency and damage turbine hardware. As turbine inlet temperatures increase, ash deposition rates increase as well.Experiments were conducted in the Turbine Accelerated Deposition Facility (TADF) at Brigham Young University to better understand ash deposition behavior at modern …

A Comprehensive Coal Conversion Model Extended To Oxy-Coal Conditions, Troy Michael Holland

Theses and Dissertations

CFD simulations are valuable tools in evaluating and deploying oxy-fuel and other carbon capture technologies either as retrofit technologies or for new construction. However, accurate predictive simulations require physically realistic submodels with low computational requirements. In particular, comprehensive char oxidation and gasification models have been developed that describe multiple reaction and diffusion processes. This work extends a comprehensive char conversion code (the Carbon Conversion Kinetics or CCK model), which treats surface oxidation and gasification reactions as well as processes such as film diffusion, pore diffusion, ash encapsulation, and annealing. In this work, the CCK model was thoroughly investigated with a …

Multi-Fidelity Model Predictive Control Of Upstream Energy Production Processes, Ammon Nephi Eaton

Theses and Dissertations

Increasing worldwide demand for petroleum motivates greater efficiency, safety, and environmental responsibility in upstream oil and gas processes. The objective of this research is to improve these areas with advanced control methods. This work develops the integration of optimal control methods including model predictive control, moving horizon estimation, high fidelity simulators, and switched control techniques applied to subsea riser slugging and managed pressure drilling. A subsea riser slugging model predictive controller eliminates persistent offset and decreases settling time by 5% compared to a traditional PID controller. A sensitivity analysis shows the effect of riser base pressure sensor location on controller …

Metallization Of Self-Assembled Dna Templates For Electronic Circuit Fabrication, Bibek Uprety

Theses and Dissertations

This work examines the deposition of metallic and semiconductor elements onto self-assembled DNA templates for the fabrication of nanodevices. Biological molecules like DNA can self-assemble into a variety of complex 2-D and 3-D architectures without the need for expensive patterning tools. In addition, self-assembled DNA templates can be designed to controllably place functional nanomaterials with molecular precision. These characteristics make DNA an attractive template for fabricating electronic circuits from biological molecules. However, electrically conductive structures are required for electronic applications. While metallized DNA nanostructures have been demonstrated, the ability to make thin, continuous wires that are electrically conductive still represents …

Assessing The Effects Of Sensitizing Tungsten Oxide With Zinc Telluride, Chengeto Kazuva

Theses and Dissertations

This thesis is a comparison study of the performance of plain tungsten oxide (WO₃) thin films and tungsten oxide thin films sensitized with zinc telluride (ZnTe) as photoelectrocatalysts. Tungsten oxide and zinc telluride are semiconductors which were prepared on indium tin oxide (ITO) coated glass, and subsequently studied for water splitting applications. The main method of synthesis employed was electrochemical deposition. Tungsten oxide thin films were deposited from a precursor solution of peroxotungstic acid while the zinc telluride thin films were deposited from a solution containing dissolved zinc sulfate heptahydrate, sulfuric acid and tellurium dioxide. Surface morphology, film composition and …

Production Of Mesophase Pitch From Gasified Lignin-Derived Tars, Adedayo O. Idowu

Theses and Dissertations

Lignin tars are created as a by-product of lignin gasification. Significant effort has gone into minimizing tar production. However, no process has been shown to completely eliminate its formation. As a result, the tar is being used to manufacture low value products such as asphalt, or is being used as a fuel in fixed combustion systems.

The research presented here is part of an effort to increase the viability of using lignocellulosic biomass as a feedstock to produce high value products. We tested the postulate that tars derived from lignin could be processed into a mesophase pitch allowable for conversion …

Decellularization And Recellularization Processes For Whole Porcine Kidneys, Nafiseh Poornejad

Theses and Dissertations

Concern over kidney disease has increased dramatically in recent years within the medical community. It is estimated that approximately one in fifteen Americans, nearly 20 million people, experience chronic kidney disease with most of those diagnosed progressing to kidney failure. The ultimate treatment available for end stage renal failure is whole kidney transplantation. However, there are very few kidneys available for patients to receive and those patients who are fortunate enough to receive an organ must remain on immunosuppressive medication for the remainder of their lives. The United States Department of Health & Human Services have reported that 18 people …

Toxicological Differences Between Perfluoroalkyl Substances (Pfas) Isomers Using Developmental Biomarkers, Gabriel A. Cantu

Theses and Dissertations

Perfluoroalkyl substances (PFAS) are metabolically stable synthetic chemicals that have been manufactured for commercial and industrial purposes since the 1950s. PFAS possess surfactant properties that make them ideal to fight hydrocarbon fires and are therefore present in aqueous film forming foams (AFFF). Furthermore, AFFF may contain blends of both linear and branched PFAS isomers. Research suggests that branched PFAS isomers have greater relative placental transfer efficiencies than their linear counterpart, but few studies have evaluated their toxicity. Therefore, the sustained use of AFFF in the U.S. Air Force presents a risk of branched PFAS exposures in pregnant females. This study …

Engineering Cell-Free Protein Synthesis Technology For Codon Reassignment, Biotherapeutics Production Using Just-Add-Water System, And Biosensing Endocrine Disrupting Compounds, Sayed Mohammad Salehi

Theses and Dissertations

Cell-free protein synthesis is an emerging technology that has many applications. The open nature of this system makes it a compelling technology that can be manipulated to answer many needs that are unavailable in other systems. This dissertation reports on engineering this technology for: 1) sense codon emancipation for incorporation of multiple unnatural amino acids; 2) expressing a hard-to-express anticancer biotherapeutic and introducing a just-add-water system; 3) a biosensing ligand that interacts with nuclear hormone receptors. Emancipating sense codons toward a minimized genetic code is of significant interest to science and engineering. A promising approach to sense codon emancipation is …

Synthesis Of Novel, Highly Bio-Based Monomeric Materials Derived From Lignocellulosic Biomass And Their Respective Epoxy Resins, Polycarbonates, And Polyesters, Joseph Randall Mauck

Theses and Dissertations

The development of high performance polymers from renewable feedstocks is a crucial step toward a global economy that is less dependent on fossil resources and has been a field of increasing study. The development of novel and interesting bio-based monomers, resins, and functional building blocks is critical to the improvement of polymers produced across the field, as well as to increasing the resource base from which chemical and materials engineers can draw to meet specific polymer property requirements. To this end, interesting tri-functional (trisguaiacol) and 4-vinyl guaiacol based hetero-difunctional monomers were developed and screened for preliminary polymer properties. The applications …

Theoretical Investigation Of The Catalytic Hydrodeoxygenation Of Levulinic Acid Over Ru (0001) Catalyst Surface, Osman Mamun

Theses and Dissertations

Due to the rapidly declining fossil fuel reserves and the onset of global climate change, the development of active, selective, and stable catalytic materials for the efficient production of biomass derived platform chemicals, i.e., levulinic acid (LA), succinic acid (SA), γ-valerolactone (GVL) etc., is receiving considerable attention in order to produce second generation biofuels and commodity chemicals. Though solid lignocellulosic biomass is significantly cheaper than petroleum; however, the available technology is the significant barrier for large scale utilization of biomass for the production of biofuels. The development of biomass conversion technology requires, 1) identification of potential biomass chemicals that can …

Supercritical Carbon Dioxide Treatment Of Natural Biomaterials For Tissue Engineering Applications, Dominic M. Casali

Theses and Dissertations

The number of people requiring an organ transplant in the United States has increased considerably over the past 25 years, but the number of organ donations has stagnated; over 8,000 people now die annually while awaiting a transplant or become too sick to receive one. Tissue engineering (TE), the design and production of artificial tissues and organs in vitro, has been proposed to alleviate this problem. Though synthetic polymers offer tunable mechanical and biochemical properties, natural biomaterials have recently garnered attention in TE for their high degree of biocompatibility and ability to direct cell proliferation and constructive tissue remodeling. Yet …

Pollutant Formation In Oxy-Coal Combustion, Nujhat Choudhury

Theses and Dissertations

With the increasing levels of carbon dioxide (CO2) in the atmosphere, researchers are driven to seek cleaner combustion techniques to burn coal for power generation. Oxy-coal combustion is a promising technique to cut down CO2 emissions. This technology requires the introduction of a pure oxygen (O2) stream and a recycled flue gas stream into the boiler instead of air. Flue gas stream generated from the system will be low in volume and highly concentrated in CO2. Thus, the capture and sequestration process will be facilitated. But, one of the concerns of adopting this technology is the altered chemistry of pollutants …

Statistical Mechanics Of Lipid-Liquid Crystal Systems: From Fundamentals To Sensing Applications, Donya Ohadi Kabir Maghsudlu

Theses and Dissertations

Understanding the thermodynamics of small systems has a well-established history. The non-intuitive behavior of the intensive properties of small systems comprised of less than a few hundred particles has important implications in many areas of engineering and materials science. Nevertheless, many open questions about the thermophysical properties of systems not in the thermodynamic limit remain unanswered. In the first part of this work, we explore the consequences of the coupling of two small subsystems that together make up a larger isolated system through the use of statistical mechanics and molecular dynamics simulations of Lennard-Jones particles in two dimensions. The results …

Renewable Carbon From Lignin Biomass And Its Electrode And Catalyst Applications In Batteries, Supercapacitors, And Fuel Cells, Muslum Demir

Theses and Dissertations

Over the last century, almost all of the carbon materials developed for the energy industry are derived from fossil fuels. The growing global concerns about energy needs, fossil fuels consumption, and the related environmental issues have motived scientists to find new, green and sustainable energy resources such as the wind, solar and biomass energy. Essentially, biomass-derived materials can be utilized in energy storage and conversion devices such as Li-ion batteries, fuel cells, and supercapacitors. Among the biomass resources, lignin is a high volume byproduct from the pulp and paper industry and is currently burned to generate electricity and steam. The …

Stilbenes: Therapeutic Interventions Targeting Amyloid Β Protein Aggregation In Alzheimer’S Disease, Yiying Wang

Theses and Dissertations

Alzheimer’s disease (AD) is the most common form of dementia and accounts for 60-80 % of all dementia cases. In the United States, AD is ranked as the 6th leading cause of death and it is the only one among the top 10 that cannot be prevented, treated or even slowed. All FDA approved drugs focus on attenuating the symptoms for a limited time by regulating neurotransmitters without any intervention with the underlying disease process. A major player in the initiation and development of this debilitating disorder is the misfolding and subsequent aggregating of amyloid-β (Aβ) peptide. This aggregation process …

Ultrathin Graphene Oxide Membranes For Water Purification: Fundamentals & Potential Applications, Weiwei Xu

Theses and Dissertations

To develop ultrathin GO membranes with both high permeation rate and excellent selectivity, it is essential to understand the interlayer nanostructure and its influence on water purification performance. We purposely deposited GO at a fast rate and at a rate ~12 times slower to control the interlayer nanostructure of the resulting membranes. The d-spacing difference between proposed thermodynamically favored interlayer structure which formed at slow deposition rate and another relative randomly packed interlayer structure formed at fast deposition rate were corroborated by XRD, organic vapor deposition, and AFM. Molecular dynamics simulations further confirmed that, in type I structure, functionalized patches …

Co2 Capture From Flue Gas By A Psa Process Using A Novel Structured Adsorbent, Nima Mohammadi

Theses and Dissertations

First adsorption equilibrium isotherms for N2, O2, Ar and CO2 on zeolite 13X were measured at three temperatures (25, 50, 75 °C) and pressures up to 110 kPa with a volumetric method and validated by also measuring the same isotherms with a gravimetric system.

Then a comprehensive 2-D mathematical model was developed to study the fundamentals of adsorption processes in parallel channel structured adsorbents. The results clearly indicated that under studied circumstances the plug flow condition can be assumed and therefore the system is not subject to premature breakthrough.

The pressure drop of corrugated structured adsorbents with narrow triangular channels …

Modeling Battery Performance Due To Volume Change In Porous Electrodes Due To Intercalation, Taylor R. Garrick

Theses and Dissertations

The demand for energy continues to increase as the economies of developing countries become more modern and show an increased need for a reliable energy infrastructure in order to meet the increased demand associated with a large and more mobile population. An increased demand puts a strain on all sectors, however it is specifically noticeable in the transportation sector where a significant portion of the fuel utilized for transportation comes from petroleum and other fossil fuels. Recently, using alternative forms of energy for transportation has become reality, and in turn, using electricity as a transportation fuel has gained significant momentum, …

Rational Synthesis Of Catalysts For Biomass Conversion, Qiuli Liu

Theses and Dissertations

With climate change due to global warming, the production of hydrocarbon fuels and chemicals from renewable biomass resource has become more pressing in recent decades. The biggest challenge in biomass conversion is to develop active, selective and stable catalysts for particular applications. The objective of this research is to optimize catalytic performance for hydrodeoxygenation (HDO) and hydrogenation reactions by enhancing the stability of the support, tuning metal particle size, and controlling surface composition.

The high content of water in bio-oil and the aqueous environment of the upgrading process requires a hydrothermally stable catalyst. The hydrothermal stability has been effectively improved …

Development Of Novel Catalysts For Air Pollution Control, Chao Wang

Theses and Dissertations

The development of economy strongly related with increased consumption of fossil fuels, which causes severe air pollution issue. With more and more strict environmental regulations implemented all over the world, robust and efficient emission control technologies need to be innovated and applied to overcome the pollution challenge. This dissertation focuses on utilizing heterogeneous catalysis to eliminate carbon monoxide (CO), hydrocarbons (CH_x) and nitric oxides (NO_x) emissions produced from fossil fuel combustion.

The first type of catalyst is Pd supported on Mn-Ce solid solution. It achieves 100% CO conversion at room temperature. The high activity is attributed …

Structural, Interfacial, And Electrochemical Properties Of Pr2nio4+Δ – Based Electrodes For Solid Oxide Fuel Cells, Emir Dogdibegovic

Theses and Dissertations

Currently, the electrochemical performance and performance durability of solid oxide fuel cells (SOFCs) are limited by cathode materials. The high polarization resistance and phase instability of the cathode are two major challenges to hinder the commercialization of SOFC systems. Two families of oxides are presently known as potential cathode materials for SOFCs: (1) the perovskite family of oxides with a general formula of ABO₃, and (2) the Ruddlesden-Popper (RP) family of oxides (e.g. nickelates) with a general formula of A₂BO₄. The electron-hole conduction in these materials occurs simultaneously with oxygen ion conduction based on …

Determination And Validation Of High-Pressure Equilibrium Adsorption Isotherms Via A Volumetric System, Hind Jihad Kadhim Shabbani

Theses and Dissertations

Adsorption equilibrium isotherms for N2, CO2, and CH4 on zeolite 13X were investigated at three different temperatures (25.5, 50.5 and 75.5 ̊ C) and a pressure range of (0-6.89475) MPa for CH4 and N2 and in the range of (0-4.82633) MPa for CO2 using built in volumetric apparatus. The results were validated using with a volumetric system (ASAP) at the same temperatures and a pressure up to (160-110) KPa respectively. The experimental results were correlated using three process Langmuir (TPLM). The correlated isotherms were then used to calculate the isosteric heat of adsorption for the three gases on 13X. The …

Computational All Atom Energy Density Landscape Mappings Of Intra-Protein Interactions From Static And Dynamic Ensemble Structure Data, Oscar H. Bastidas

Theses and Dissertations

Understanding the energetic and dynamic behavior of natural protein fluctuations is critical to elucidating important information associated with a multitude of protein functions including signaling processes, enzyme behavior, aggregation pathways etc... This information is also critically important in the development of novel and effective strategies aimed at target proteins associated with pathologies and disease. In order to obtain such useful information, tools and techniques are lacking that: 1) permit the efficient quantitative analysis of fluctuation behavior of existing protein structure ensembles and 2) permit computationally generated natural fluctuation states of proteins at relatively large timescales demanded by the need for …

Photoelectrochemical Cell Constructed From Bby Membrane With Various Substrate Materials, Yang Liu

Theses and Dissertations

Photoelectrochemical cells have been intensively studied in recent years with regard to using thylakoid and photosynthesis system I/II. BBY membrane is another protein complex that has potential to be utilized to build photoelectrochemical cells. Within the BBY membrane lies the highly active photosynthesis system II complex, which upon light activation, generates electrons transported within the electron transport chain during photosynthesis in green plants. This study presents an approach of immobilizing thylakoid or BBY membrane onto gold nanoparticle modified gold plate or multi-walled carbon nanotube (MWCNT) modified indium tin oxide vi (ITO) coated glass substrate. The results show that BBY membrane …

Fabrication Of Flexible, Biofunctional Architectures From Silk Proteins, Ramendra K. Pal

Theses and Dissertations

Advances in the biomedical field require functional materials and processes that can lead to devices that are biocompatible, and biodegradable while maintaining high performance and mechanical conformability. In this context, a current shift in focus is towards natural polymers as not only the structural but also functional components of such devices. This poses material-specific functionalization and fabrication related questions in the design and fabrication of such systems. Silk protein biopolymers from the silkworm show tremendous promise in this regard due to intrinsic properties: mechanical performance, optical transparency, biocompatibility, biodegradability, processability, and the ability to entrap and stabilize biomolecules. The unique …