Engineering Commons^™

In Mold Flow Of Long Fibers In Compression Molding Process, Gleb Meirson

Electronic Thesis and Dissertation Repository

Long Fiber Thermoplastics (LFT) are promising new materials with high physical properties and low density. These high properties are obtained by embedding very long fibers (~100 mm) into a thermoplastic matrix. Such a high fiber length dictates the use of a compression molding process for manufacturing as the length of discontinuous fibers in injection molding is limited by pellet length.

LFT composites are of great interest for the automotive industry. These materials are already used in some interior and exterior car parts such as bumpers, seat structures, door module etc. This research is inspired by the desire to manufacture load …

Electrochemical Oxidation Of Antibiotic, Antihistamine, Analgesic And Cns Stimulant Pharmaceuticals, Md Mosaddek Hossen

Chemical and Biological Engineering ETDs

Electrochemical oxidation is a common method for the degradation of chemicals by applying potential at a definite value. In this research, ‘cyclic voltammetry’ experiments were conducted to find out the oxidation potential for 8 different pharmaceuticals. Mainly, 3 different pH solutions (pH 6.0, 7.5, 9.0) and 9 different concentrations (1, 2, 5, 10, 20, 50, 100, 200, 500 µM) were studied for each of the pharmaceuticals in this experiments. Acetaminophen, Ibuprofen, Naproxen Sodium, Caffeine showed oxidation peak at 0.34-0.79V, 1.37- 1.39V, 0.94-1.01V, 1.44-1.55V respectively at different pH and concentrations. Antibiotic and antihistamine pharmaceuticals i.e. Erythromycin Hydrate, Triclosan, Sulfanilamide, Diphenhydramine Hydrochloride …

Multiscale Modeling Of Electrolytes For Energy Storage And Conversion, Fatemeh Sepehr

Doctoral Dissertations

Fuel cells, redox flow batteries, and secondary ion batteries are under active investigation to fulfill the requirements of efficient and sustainable energy storage and conversion technologies. The discovery of high-performance stable electrolytes that are relatively cheap and versatile is crucial to the commercialization of these electrochemical devices and necessitates a comprehensive understanding of the materials (i.e., from the atomistic to continuum levels). This dissertation is on multiscale modeling and simulations of several electrolytes under consideration in vanadium redox flow batteries (VRFBs), alkaline fuel cells (AFCs), or secondary magnesium batteries.

The hydrated structure and associated solvation Gibbs energies were determined for …

Innovative Electrode Nanocomposites For Energy Storage And Conversion Systems, Yiran Wang

Doctoral Dissertations

Nanocomposites emerged as suitable alternatives for electrode materials, are defined as “two or more materials with different properties remain separate and distinct on a macroscopic level within one unity and with any dimension in any phase less than 100 nm”. Recently, polymer/carbon based nanocomposites have attracted significant research interests for energy applications due to their multi-functionalities, improved structure stability and ease of production. This dissertation work focusing on the development of innovative electrode nanocomposites for proton exchange membrane fuel cell, supercapacitor and electrochromic applications.

Chapter 1 is an introduction. Chapter 2 & 3 focus on the synthesis of Pd-based nanocatalysts …

Large Scale Brownian Dynamics Simulation Of Dilute And Semidilute Polymeric Solutions, Amir Saadat

Doctoral Dissertations

Excluded Volume (EV) and Hydrodynamic Interactions (HI) play a central role in static and dynamic properties of macromolecules in solution under equilibrium and nonequilibrium settings. The computational cost of incorporating HI in mesoscale Brownian dynamics (BD) simulations, particularly in the semidilute regime has motivated significant research aimed at development of high-fidelity and efficient techniques.

In this study, I have developed several algorithms for the mesoscale bead-spring representation of a macromolecular solution in dilute and semidilute regimes. The Krylov subspace method enables fast calculation of single chain dynamics with simulation time scaling of O(N_b²) [order N …

Electrostatic Nanosmearing Architecture Of Additive Functional Groups During High Shear Mixing Of Pharmaceutical Blends, Sajan Kumar Chatarla

Masters Theses

The main objective of the research project is to detect and quantify the rate and extent of nanosmearing of hydrophobic functional groups of additives on multiple pharmaceutical particles during high shear mixing of formulations due to electrostatics affecting critical blend properties on the bulk scale. We accomplished this task by systematically detecting the electrostatics during powder flow and its consequence on the nanosmearing distribution of additives during mixing. In the first stage, the electrostatic behavior of particles was correlated to the powder flow. Secondly, its relative influence on nanosmearing of additives during mixing was determined by developing a methodology to …

Fundamental Studies Of Flame Propagation In Lean-Burn Natural Gas Engines, Zhiyan Wang

Open Access Dissertations

Lean-burn natural gas engines offer enhanced thermal efficiencies and reduced soot and NOx emissions. However, cycle-to-cycle variability in combustion that can result from unreliable ignition, variability in equivalence ratio and quenching is a challenge. Reliability of ignition can be improved by employing a dual-fuel ignition strategy in which a small quantity of diesel fuel is injected to initiate ignition. Computational studies of n-heptane/methane-air mixing layers are performed to provide insight into the fundamental physics of dual-fuel ignition. The results show that the characteristic time required for steady premixed flame propagation has three components: time for autoignition to occur, time for …

Design Of Nitroxide-Based Radical Polymer Materials For Electronic Applications, Martha E. Hay

Open Access Theses

Radical polymers represent a new class of organic electronic materials that rely on an oxidation-reduction (redox) reaction to transport charge. That is, stable radical sites pendant to the polymer backbone communicate electronically through a rapid oxidation-reduction reaction. This redox mechanism has previously been established as effective for charge-storage applications (e.g., secondary batteries). When applied in the solid state, radical polymers demonstrate electrical conductivity on par with that of first-generation conjugated polymer electronic materials. This initial success has prompted interest in developing design rules for radical polymers. Specifically, this thesis explores the impact of radical density in a polymer …

Degradation Of High Performance Polymeric Fibers: Effects Of Sonication, Humidity And Temperature On Poly (P-Phenylene Terephthalamide) Fibers, Nelyan Lopez-Perez

Open Access Theses

High performance fibers are characterized by properties such as high strength and resistance to chemicals and heat. Due to their outstanding properties, they are used on applications under harsh environments that can degrade and decrease their performance. Fiber degradation due to different chemical and mechanical factors, is a process that begins at a microstructural level. Changes in the polymer’s chemical or physical structure can alter their mechanical properties. Knowledge of the structure-properties relationship and the effects of environmental chemical and physical factors over time, is crucial for the improvement and development of high performance fibers.

In this study ballistic fibers …

Plasmonic Pervaporation For Sustainable Mixture Separation, Ty Austin

Chemical Engineering Undergraduate Honors Theses

The U.S. Department of Energy suggests that ca. 40% of the total energy consumed in the chemical and refining industries is used for distillation.¹ One potentially energy efficient alternative is pervaporation, a membrane separation process that uses differences in solvent permeability and vaporization rates to encourage mixture separation. Pervaporation has become a valuable tool in the processes of producing biofuels, recovering water, and removing solvent.^2,3 However, implementation has been hindered by heating the feed to the membrane and cooling the unpermeated retentate to increase membrane throughput at a higher energy cost. Preliminary research has shown that locally heating …

Hollow Fiber Membranes For Artificial Lung Applications, Lauren Reed

Chemical Engineering Undergraduate Honors Theses

Artificial lungs are in use, but difficult issues remain in the field of membrane development related to fouling issues. Currently there are external artificial lungs circulating blood outside the body, taking out the carbon dioxide, and inserting oxygenated blood back into the body. An example of this type of machine is the ExtraCorporeal Membrane Oxygenation (ECMO) machine currently used in hospitals. The ECMO takes over the functions for both the lungs and the heart but is only available for short term use by patients with respiratory failure due to infections [1]. The fibers in the machine develop fouling due to …

Impedance-Resolved Performance And Durability In Redox Flow Batteries, Alan Michael Pezeshki

Doctoral Dissertations

The realization of redox flow batteries (RFBs) as a grid-scale energy solution depends on improving the performance and lifetime of the technology to decrease the high capital costs. The electrodes are a key component in the RFB; performance enhancement is often achieved through chemical or thermal treatments of commercially available porous carbon materials.

This dissertation uses impedance spectroscopy-based methods to gain insight into performance and durability in RFBs, enabling intelligent cell design. Initial work focused on understanding the impact of improved electrode and membrane properties on system performance. An accelerated stress test was then developed that can be used to …

Elucidating The Effects Of Metabolic State On Nanoparticle Distribution In Mice And In Vitro Uptake, Kevin James Quigley

Doctoral Dissertations

Since almost 70% of the U.S. population over 20 years old is overweight and 30% is obese, with much of the western world following suit, many patients that will potentially be administered circulating nanoparticles designed to localize to tumors and avoid non-target areas will have significant amounts of white adipose tissue (WAT), enlarged livers, and additional metabolic complications such as type 2 diabetes. However, studies on nanoparticle biodistribution and efficacy take place almost without exception in lean rodents with healthy metabolic states. In this work, I determined the biodistribution of model nanoparticles – neutral filomicelles and polystyrene spheres both carrying …

Measurement Of Activity And Stability Of Physical Vapor Deposition (Pvd) Coated Crystal Surfaces, Anuradha Krishnan

Masters Theses

The overall objective of this research work is to investigate the hydrophilic and hydrophobic forces acting on organic crystal planes and understanding the interaction of functional groups with additive molecular nanolayers. Crystals of acetaminophen and lactose were made and the surface forces were tested on Atomic Force Microscope (AFM). Uniformity of crystal surface was confirmed from the AFM study in the first stage. The growth factors of crystal planes as a function of time were studied. Adhesion forces on plain crystals were measured on both two different organic crystals made of acetaminophen and lactose. In the second stage, …

How A Systematic Approach To Uncertainty Quantification Renders Molecular Simulation A Quantitative Tool In Predicting The Critical Constants For Large N-Alkanes, Richard Alma Messerly

Theses and Dissertations

Accurate thermophysical property data are crucial for designing efficient chemical processes. For this reason, the Design Institute for Physical Properties (DIPPR 801) provides evaluated experimental data and prediction of various thermophysical properties. The critical temperature (T_c), critical density (ρ_c), critical pressure (P_c), critical compressibility factor (Z_c), and normal boiling point (T_b) are important constants to check for thermodynamic consistency and to estimate other properties. The n-alkane family is of primary interest because it is generally assumed that other families of compounds behave similarly to …

Nanoemulsions Within Liposomes For Cytosolic Drug Delivery To Multidrug-Resistant Cancer Cells, Jacob Brian Williams

Theses and Dissertations

Cancer cells that survive chemotherapy treatment often develop resistance to the administered chemotherapeutics, as well as to many other types of drugs, because the cancer cells increase their production of efflux pumps in the cell. This undesired phenomenon of resistance to cancer drugs is known as multidrug resistance. This work uses a novel drug carrier, called an eLiposome, to achieve cytosolic drug delivery to kill multidrug-resistant cancer cells. An eLiposome consists of a perfluoropentane (PFC5) emulsion droplet inside of a liposome. Folate attached to the eLiposome facilitates uptake into the cell. The PFC5 droplet is metastable at body temperature, but …

Effects Of Tethering Placement And Linker Variations On Antibody Stability On Surfaces, Rebecca Ellen Grawe

Theses and Dissertations

An antibody microarray consists of antibody bound to a surface. Antibody microarrays have great potential in many fields, particularly as a tool to detect antigens. Unfortunately, antibodies suffer from poor performance. A greater understanding of how antibodies interact with surfaces would improve microarray design and performance, but experimental methods fall short of being able to observe these interactions. Therefore molecular simulation has emerged as the primary method to study protein/surface interactions.The simulations here were coarse grain simulations performed using the model of Karanicolas and Brooks. Additionally, an advanced surface model was used that allows for different surface chemistries. PyMBAR analysis …

Removal Of Carboxylic Acids And Water From Pyrolysis Oil, George Alexander Marshall

Graduate Theses and Dissertations

Over 70% of the world’s energy consumption is provided by fossil fuels and with those reserves depleting at a fast rate, alternative energy sources or methods are needed to support the world’s energy needs. This research was done in an attempt to make it more economically feasible to produce fuel products, such as bio-diesel, from the upgrading of bio-oil obtained from the pyrolysis of biomass waste material such as sawdust. The high water and oxygenated compound content of bio-oil make it undesirable for fuel use; however, two methods involving surface modified commercial membranes were utilized in hopes of overcoming these …

Haul Truck Tires Recycling, Omkar Bhave

Chemical Engineering Undergraduate Honors Theses

The disposal of large Off-the-Road (OTR) tires is an increasingly important concern. These tires can weigh up to 8,450 pounds with an overall diameter and width of approximately 140.7 inches and 45.1 inches respectively. OTR tires are used for mining vehicles such as haul trucks, wheel loaders, backhoes, graders, and trenchers.[1] These new tires cost between $38,000 and $50,000 each, depending on multiple factors including oil prices and the cyclical nature of the industry. Haul trucks contain six tires per vehicle, and mines replace these tires around every 9-12 months.[2] Statistics regarding discarded OTR tires are not provided by the …

Design, Construction, And Preliminary Testing Of A Square Cross-Sectional Mixing Chamber, Holly Holmes-Smith

Chemical Engineering Undergraduate Honors Theses

Throughout the US, large quantities of chlorine are produced and transported by rail. In the past, train accidents led to deadly accidental releases and the need for mass evacuation. However, moving people unnecessarily may cause pandemonium or danger to health for sensitive members of the public. In these past cases, the models used for evacuation distances did not accurately predict the impact of the chlorine release, but these models did not take into account the reactivity of chlorine. Because chlorine is a highly reactive gas, it is absorbed into the surrounding environment which reduced the amount of chlorine in the …

Chlorpyrifos Removal For Wastewater Reuse, Indran Kamalanathan

Chemical Engineering Undergraduate Honors Theses

Approximately 1.2 billion people around the world live in areas of physical water scarcity. This could increase to half of the world’s population by 2030 and could displace 24 to 700 million people unless steps are taken to ensure adequate water supply.¹ Water scarcity is an escalating issue within the United States, specifically in Western inland states with arid climates. This scarcity is encouraging communities to investigate tertiary level municipal wastewater treatment, allowing for reuse of wastewater. Unfortunately, wastewater contains numerous contaminants that are not regulated by the Environmental Protection Agency (EPA) under the Safe Drinking Water Act (SDWA). …

Synthesis And Characterization Of Porous Liquids, Yuanyou Gao

Masters Theses

Porous liquids consisting of modified hollow spheres which are fabricated by surface engineering with suitable corona and canopy species is one of interesting porous liquids reported recently. By taking advantage of the liquid-like polymeric matrices as a separation medium and the empty cavities as a gas transport pathway, porous liquids can function as promising candidates for postcombustion gas separation and thermal insulation purposes. Moreover, this synthetic strategy can be applied to other nanostructure-based porous liquids, facilitating production of porous liquids with specific request. In this thesis, a new member of this type of porous liquid with hollow spheres ranging from …

Membrane Chromatography For Bioseparations: Ligand Design And Optimization, Zizhao Liu

Graduate Theses and Dissertations

Membrane chromatography, or membrane adsorber, represents an attractive alternative to conventional packed bed chromatography used in downstream processing. Membrane chromatography has many advantages, including high productivity, low buffer consumption and ease to scale up. This doctoral dissertation focuses on developing novel polymeric ligands for protein separations using membrane chromatography. Atom transfer radical polymerization (ATRP), known as a controlled radical polymerization technique, has been used to control the architecture of grafted polymeric ligands. The center theme of this dissertation is to develop new polymeric ligands and investigate how the polymer’s property (e.g. flexibility, hydrophobicity) and architecture (e.g. chain density, chain length) …

Preliminary Investigation For The Development Of Surrogate Debris From Nuclear Detonations In Marine-Urban Environments, Adam G. Seybert

Masters Theses

No nuclear weapon has ever been detonated in a United States city. However, this also means the nuclear forensic community has no actual debris from which to develop analytical methods for source attribution, making the development of surrogate nuclear debris a vital undertaking. Moreover, the development of marine-urban debris presents an unusual challenge because unlike soil and urban structures, which remain compositionally consistent, the elemental composition of harbor and port waters fluctuates considerably due to natural phenomenon and human activity. Additionally, marine vessel composition and cargo can vary dramatically. While early US nuclear tests were carried out in shallow-water coastal …

Design And Synthesis Of Dynamic Covalent Polymer Scaffolds With Controlled Architectures, Emily Annette Hoff

Dissertations

The design and synthesis of functional, controlled polymer architectures is essential to the development of new materials with precise and tailorable properties or applications. The work described in this dissertation focuses on the development of controlled polymer architectures with dynamic linkages for the design of multifunctional materials and surfaces via robust, efficient, and stimuli-responsive strategies.

In Chapter III, a post-polymerization modification strategy based on ambient temperature nucleophilic chemical deblocking of polymer scaffolds bearing N-heterocycle blocked isocyanate moieties is reported. Room temperature RAFT polymerization of three azole-N-carboxamide methacrylates, including 3,5-dimethyl pyrazole, imidazole, and 1,2,4-triazole derivatives, afforded reactive polymer scaffolds …

Nanostructured Morphologies In Glassy Polymer Networks, Brian Greenhoe

Dissertations

The body of this work describes a novel approach for the dispersion of multi-walled carbon nanotubes in a high T_g epoxy prepolymer matrix using a twin screw high-shear continuous reactor. The method demonstrated improves on previous dispersion methods in several ways. It offers increased efficiency through excellent heat transfer, while being solvent-less, scale-able, and tailorable to drive dispersion states to judiciously chosen dispersion states. Furthermore, it was shown that dispersion state and agglomerate morphology can be directed, in several ways, through processing conditions and also by controlling the matrix viscosity profile through cure. Broadband dielectric spectroscopy, optical hot-stage microscopy, …

Evaluation Of Smart Water Flooding In A Selected Uae Carbonate Oil Reservoir, Mohammad Jasem Khalifi

Chemical and Petroleum Engineering Theses

Water flooding is by far the most common method of improved oil recovery applied in oil reservoirs. Water is the cheapest source of external energy that has been used over decades in water flooding schemes, provided that the damage does not adversely affect its injectivity. Displacement efficiency of water flooding can be significantly affected by crude oil/water/rock interactions. Historically, some consideration was given to such interactions in the practice of reservoir engineering. In recent years, extensive research in this area has documented that higher oil recoveries can be obtained when low-salinity water is injected in a formation with high salinity …

Lignin Maximization: Analyzing The Impact Of Different Feedstocks And Feedstock Ratios Using Organosolv Fractionation, Marc Banholzer

Masters Theses

Over-exploitation of fossil fuels coupled with increasing pressure to reduce carbon emissions are prompting a transition from conventional petrochemical feedstocks to sustainable and renewable sourced carbon. The use of lignocellulosic biomass as a feedstock for integrated biorefining is of current high interest, as separation into its component parts affords process streams of cellulose, hemicellulose and lignin, each of which can serve as a starting point for the production of biobased chemicals and fuels. Given the large number of potential sources of lignocellulosic feedstocks, the biorefinery will need to adapt to the supplies available over a normal growing season. Of particular …

Effects Of Ultrasonic Transducers On Heat Transfer In Packed Particle Beds, David Patrick Moseley

Masters Theses

The objective of this study was to determine the effects of ultrasonic transducers on heat transfer in a packed particle bed heat exchanger. Although substantial research has been devoted to ultrasound, and the associated improvements in heat transfer, data regarding the effects on packed particle beds is non-existent. This is of particular interest given the potential to improve heat transfer in a wide variety of packed particle bed systems. A 42.9% increase in the heat transfer rate was demonstrated as the result of improved fluid convection throughout the packed particle bed. Secondary effects, including acoustic cavitation, acoustic streaming and local …

Conductive Inks And Films Via Intense Pulsed Light., Gabriel L. Draper

Electronic Theses and Dissertations

This research focuses on the investigation of Earth abundant copper and carbon based nanomaterials that are subjected to Intense Pulsed Light Processing to create conductive films, as future flexible electronics and renewable energy solutions would benefit from the quick and scalable production of conductive films. Use of nanomaterials in their oxide/hydroxide forms leads to higher stability in aqueous inks for efficient large area solution deposition. IPL Processing utilized 2044 μs pulses ranging from 589 J - 2070 J over an area of 1.9 cm x 30.5 cm, with energy densities of 10.1, 12.8, 15.8, 19.2, 22.9, 26.8, 31.1 and 35.7 …