Engineering Commons^™

Non-Invasive Detection And Assessment Of Coronary Stenosis From Blood Mean Residence Times., Javad Hashemi

Electronic Theses and Dissertations

Coronary artery stenosis is an abnormal narrowing of a coronary artery caused by an atherosclerotic lesion that reduces lumen space. Fractional flow reserve (FFR) is the gold standard method to determine the severity of coronary stenosis based on the determination of rest and hyperemic pressure fields, but requires an invasive medical procedure. Normal FFR is 1.0 and FFR RT, to account for varying volume and flow rate of individual segments. Blood_RT was computed in 100 patients who had undergone the pressure-wire FFR procedure, and a threshold for Blood_RT was determined to assess the physiological significance of a stenosis, …

Stabilization Of Bimodal Colloidal Systems Via Nanoparticle Haloing In Microgravity., Luke Hawtrey

Electronic Theses and Dissertations

Colloidal suspensions typically contain a multi-phase system of solid particles suspended in a liquid medium. Colloids are widely used in industrial applications such as inks, paints, motor oils, foods, cosmetics, and many more. Colloidal systems are typically formed by the interaction of the attractive van der Waals forces and one or more repulsive forces. These repulsive forces include electrostatic repulsion, steric hindrance, and nanoparticle haloing. Nanoparticle Haloing (NPH) is a phenomenon discovered in 2001 as a viable method to stabilize colloidal systems of uncharged silica microparticles using highly charged zirconia nanoparticles. For this thesis the effects of NPH were tested …

Breaking Coastal Hypoxia: Destratification Of Gulf Of Mexico Deadzone To Encourage Oxygen Transport Downwards To Maintain Marine Fauna, Veda Thipparthi

LSU Master's Theses

As a consequence of seasonal eutrophication and human input, a vast hypoxic area termed The Dead Zone develops every year in the Gulf of Mexico (GOM) during summer along the Louisiana coastline characterized by vertical seawater density-stratification with oxygen concentrations less than 2 mg.l^-1 at the seafloor. It poses a threat to bottom-dwelling faunae and their environment which has negative ecological and economic consequences. This project aims to mitigate hypoxia by employing mechanical impellers placed at strategic water depths and locations in the Gulf. Enhanced transport of oxygen results by mixing oxygen-enriched seawater at the surface, downward into the …

The Effects Of Temperature On The Yields Of Aliphatic And Aromatic Products From The Supercritical Pyrolysis Of 1-Octene, Elizabeth Anne Hurst

LSU Doctoral Dissertations

Prior to their combustion, fuels for future high-speed aircraft are expected to experience supercritical conditions, leading to the production of polycyclic aromatic hydrocarbons (PAH), precursors to solid carbonaceous deposits, via pyrolytic reactions. These solid deposits can clog fuel-transfer lines, causing unsafe aircraft operation. To prevent the formation of fuel-line deposits, it is critical to understand the reaction pathways that lead to PAH formation in the supercritical fuel pyrolysis environment.

To better understand the role of large 1-alkenes in PAH formation, supercritical pyrolysis experiments with model fuel 1-octene, a representative 1-alkene product from supercritical n-alkane pyrolysis, have been performed. The …

Rotating Heater Pyrolyzer (Rhp): A New Pyrolysis Technology For Biochar Production, Ariel Porat

Electronic Thesis and Dissertation Repository

Biochar provides an effective and inexpensive carbon sequestration technology to combat climate change. It is formed through a process known as pyrolysis; where biomass is thermally decomposed in the absence of oxygen. In this study, a new pyrolysis reactor called the Rotating Heater Pyrolyzer (RHP) was designed and built for biochar production. RHP derived biochar properties were compared to biochars produced with a standard batch pyrolysis reactor (Pyrolytic Shaker Reactor (PSR)) to determine RHP performance. Using several biochar characterization techniques, the soil amendment potential of two solid anaerobic digestate feedstocks were investigated. Woodchip RHP derived biochar processed between 2-3 hrs …

A Comprehensive Study Of Sequential Simulated Moving Bed: Purification Of Xylo-Oligosaccharides And Fructose-Glucose, Yan Li

Electronic Thesis and Dissertation Repository

Chromatographic separation is a promising alternative for separation and purification of sugars in industry. Simulated moving bed (SMB) technique has been proven as an efficient chromatographic separation method due to its enhanced productivity and purity, reduced solvent consumption, convenient operating control, and improved separation performance for some systems with low resolution and selectivity. The sequential simulated moving bed (SSMB) is a modification of the conventional SMB process, which currently has some applications for sugar separation due to its low solvent consumption. This work mainly investigates the design strategy of the innovative SSMB process and explore its advantages and disadvantages over …

Development Of A Co-Rotating, Fully Intermeshing Twin-Screw Extruder Model For The Extrusion Of Natural Fibre Suspensions, Keller J H George

Electronic Thesis and Dissertation Repository

Twin-screw extruders are continuous processing devices that have been used in many industries concerned with the processing of multiphase fibrous suspensions, such as the food and pulping industries. While these devices offer great flexibility due to their modularity and customizability, optimization for specific applications can be challenging due to the unavailability of reliable, global models with accurate predictive capabilities. Consequently, this work seeks to eliminate this knowledge gap with the development of a novel global, composite model capable of predicting key process outputs for suspension-processing, phase-separating, co-rotating, fully-intermeshing twin-screw extruders. Creation of the novel global algorithm involved the modification of …

Interfacial Interactions And Dynamic Adhesion Of Synthetic And Living Colloids In Flow, Molly Shave

Doctoral Dissertations

This thesis focuses on the interactions between flowing particles and a surface, where hydrodynamics couples with chemical interactions in order to modify the way they come into play. First this thesis shows how electrostatic chemical heterogeneities on a flowing particle affect the interactions with a wall, using a highly tunable electrostatically heterogenous system produced by adsorbing small amounts of cationic polyelectrolytes onto silica particles in suspension and studying their behavior in flow over the fixed surface. By comparing this behavior to a system with equivalent chemical heterogeneity on a channel wall it was shown that the rotation of a particle …

Hydrodynamics Studies Of Air Dense Medium Fluidized Bed With Binary Mixtures For Dry Coal Beneficiation, Zhijie Fu

Electronic Thesis and Dissertation Repository

A systematic and comprehensive study of fluidization hydrodynamics and separation properties was conducted in a bench-scale and a semi-industrial Air Dense Medium Fluidized Bed (ADMFB) systems for dry coal beneficiation. In order to achieve the adjustment of fluidized bed density for efficient dry gravity separation, various types of binary mixtures of solid particles were tested and used as the medium materials in ADMFB. Fluidization hydrodynamics including minimum fluidization velocity, fluidized bed expansion, solids mixing/segregation, and bed density distribution were carefully investigated. A series of continuous experiments of raw coal dry beneficiation were successfully implemented in a semi-industrial ADMFB system with …

Application Of Electrostatic Dry Powder Coating Technology On Hard Capsules, Zhehao Jing

Electronic Thesis and Dissertation Repository

This project applied electrostatic dry powder coating technology on hard gelatin and HPMC capsules using Eudragit^® RS/RL and Eudragit^® L 100-55 to achieve sustained release and enteric release respectively. Dry powder coating eliminated the difficulties associated with conventional liquid coating processes such as poor adhesion and stickiness for capsules. Additionally, through optimizing sprayed plasticizer volume, the coating powders deposited on the capsules could be efficiently maximized. The weight gain of coating and the formulation of coating materials were important parameters which controlled the release profiles of coated capsules. The release mechanism of coated capsules was quite different from …

Enhanced Carbon Fiber-Epoxy Composites For Rowing Racing Shells, Rayehe Samimi

Electronic Thesis and Dissertation Repository

This thesis investigates the thermomechanical properties of two commercial composites using carbon fiber reinforcement in epoxy resins for manufacturing marine based rowing racing shells. The main goal of this project was to investigate how to control the resin properties and curing temperatures to improve the final product properties including adhesion, toughness modulus and tensile strength. Moreover, an efficient curing process was required by our supporting company to be used at low temperatures to enhance the curing characteristics and to provide improved mechanical properties. Accordingly, the current research tries to improve the manufacturing curing process and build up high performance structure …

The Use Of Electrical Resistance Tomography To Determine The Minimum Agitation Speed For Solids Suspension In Stirred Tank Reactors, Baran Teoman

Theses

Njs, the minimum agitation speed needed to just suspend all the solid particles in a solid-liquid mixture stirred in an agitated vessel, is a critical parameter to properly operate industrial tanks in a large number of industrial operations. As a result, a significant literature on Njs is available. The oldest and the most common method to measure Njs experimentally is that of Zwietering’s (Chem. Eng. Sci., 1958, 8, 244-253), where Njs can be visually obtained by determining when the solids stay at the bottom of the tank for no more than 1-2 seconds before being swept away. Although this has …

Removal And Reuse Of Phosphorus As A Fertilizer From Cafo Runoff, Kristin Moore

Chemical Engineering Undergraduate Honors Theses

Eutrophication is the process in which nutrient saturated waters promote algal blooms on the surface of the water. This limits the amount of dissolved oxygen content in the water, effectively limiting the range of species that can survive in a body of water. Concentrated animal feeding operations (CAFO) can contribute to this issue. The animals in a CAFO produce large amounts of nutrient-rich waste streams that can enter natural waterways if not properly managed and increase the problem of eutrophication. The ability to treat these waste streams and recover the excess nutrients would allow for not only the reduction of …

Influence Of Mechanical Properties Of Paper Coating On The Crack At The Fold Problem, Seyyed Mohammad Hashemi Najafi

Electronic Theses and Dissertations

Paper coating layers are subject to various stresses and deformations in many converting processes such as calendering, printing, slitting, and folding of the paper. In some cases, products may crack during folding to generate a defect called cracking at the fold (CAF). The parameters that influence these defects are not well understood. The overall goal of this thesis is to better understand the CAF behavior as related to material properties of the coating layer.

A method was developed to produce free-standing pigmented coating layers thick enough to be tested in bending as well as tension. The mechanical properties of these …

Parameters That Influence The Performance Of Dispersion Barrier Coatings, Randy Raditya

Electronic Theses and Dissertations

Barrier coating layers are important in many paper grades used in food packaging and have the potential to help reduce our use of plastics in some situations. Barrier layers to produce water proof packaging such as milk or juice cartons or coffee cups are common. Water based dispersion barrier coatings have the potential to be a low-cost alternative to extrusion coated layers. Water borne coatings are reported to be easy to recycle and break down in the environment. However, barrier properties are often less than what is desired and expected for these water borne coatings. The reason for this poor …

Plasma-Assisted Liquid Phase Epitaxy Of Gallium Nitride Using Molten Gallium., Daniel Felipe Jaramillo-Cabanzo

Electronic Theses and Dissertations

Next generation semiconductor materials such as Gallium Nitride (GaN) and Silicon Carbide (SiC) are rapidly replacing Silicon (Si) for high power and high frequency applications due to Si’s inherent limitations. Despite the advantages of GaN over SiC, adoption of GaN has been hindered due to the lack of a cost-effective bulk production technique. Thus, the inability to precure native substrates requires GaN-based architectures to be heteroepitaxially synthesized on non-native substrates, such as sapphire and even SiC. This research seeks to develop a cost effective and scalable method to produce low defect, bulk GaN encouraging the adoption of GaN based devices …

Removal And Reuse Of Phosphorus As A Fertilizer From Cafo Runoff, Hannah Young

Chemical Engineering Undergraduate Honors Theses

Eutrophication is the process in which nutrient saturated waters promote algal blooms on the surface of the water. This limits the amount of dissolved oxygen content in the water, effectively limiting the range of species that can survive in a body of water. Concentrated animal feeding operations (CAFO) can contribute to this issue. The animals in a CAFO produce large amounts of nutrient-rich waste streams that can enter natural waterways if not properly managed and increase the problem of eutrophication. The ability to treat these waste streams and recover the excess nutrients would allow for not only the reduction of …

Scale Model And Flow Visualization Of Jack Rabbit Ii Chlorine Field Test, Charlotte Williams

Chemical Engineering Undergraduate Honors Theses

The release of hazardous gases, especially accidental releases, can have a major impact on the surrounding environment and population. The history of accidental hazardous gas releases is filled with plant destruction, civilian injury, and even death. Knowledge of how these gases travel and disperse once released can significantly lessen physical harm and improve emergency procedures. The Jack Rabbit II field test was conducted in pursuit of this knowledge for a chlorine release. In this field test, a purpose-built chlorine tank was surrounded by CONEX trailers assembled in the desert in Utah to model an urban setting. Multiple releases of chlorine …

Extraction Of Tho2 From Monazite Ore, Brian T. Grim, Kevin Harricharran, Maggie Mann, Sidharth Mahajan

Chancellor’s Honors Program Projects

No abstract provided.

Study Level Design Of Thorium Oxide Production, Dylan G. Chitwood, Drake Crawford, Chase Toth

Chancellor’s Honors Program Projects

No abstract provided.

Extraction Of Thorium Oxide From Monazite Ore, Makalee Ruch, Chloe Frame, Molly Landon, Ralph Laurel, Annabelle Large

Chancellor’s Honors Program Projects

No abstract provided.

Effect Of Coagulant Recycling On Chemically Enhanced Primary Treatment Performance, Tulip Chakraborty

Electronic Thesis and Dissertation Repository

Chemically enhanced primary treatment (CEPT) process is a promising method for carbon redirection and improving the performance and efficiency of wastewater treatment processes. CEPT is employed to precipitate colloidal and suspended matter from wastewater; however, this requires a significant amount of coagulant and produces large volumes of sludge. Coagulant recovery (CR) from the precipitated sludge has the potential to reduce sludge quantities, associated costs for disposal of sludge, cost of dosing fresh coagulant by regenerating and purifying the coagulant before reuse. This research was conducted to understand the feasibility and implications of CR in municipal wastewater.

In order to evaluate …

Iron-Containing Nanoparticles For The Treatment Of Chrionic Biofilm Infections In Cystic Fibrosis, Leisha M. A. Martin

Nanoscience and Microsystems ETDs

Cystic fibrosis (CF) is the most common genetic disease resulting in the morbidity and mortality of Caucasian children and adults worldwide. Due to a genetic mutation resulting in malfunction of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein, CF patients produce highly viscous mucus in their respiratory tract. This leads to impairment of the mucociliary clearance of inhaled microbes. In addition to reduced microbial clearance, anoxic environmental conditions in the lungs promote biofilm-mode growth of the pathogenic bacterial species Pseudomonas aeruginosa. Chronic infections of P. aeruginosa begin in early childhood and typically persist until respiratory failure and death result. The …

Hazard And Operability Analysis Of An Ethylene Oxide Production Plant, Samantha Ciricillo

Senior Theses

The purpose of this work was to evaluate potential hazards and failures as part of the design and economic analysis for a chemical plant that would produce 150,000 tons of ethylene oxide per year. The Hazard and Operability (HAZOP) method of analysis was used to accomplish this goal. This method of hazard analysis involves brainstorming potential errors in a system by examining each element of each process unit in full detail. This project was focused on the reactor unit because the reactor has several important parameters that could fail, resulting in safety issues within the system. Input for this analysis …

Analysis And Control Of Aluminum Concentration In Groundwater: Mathematical Modelling And Laboratory Study, Daria Popugaeva

Electronic Thesis and Dissertation Repository

The remediation of metal-contaminated natural water bodies is prioritized due to metals toxicity, non-biodegradable properties, and accumulative behaviours leading to the increased incidence of adverse health effects. Current investigation is driven by the existing problem of elevated aluminum concentrations in the groundwater of Khibiny alkaline massif (Kola Peninsula). The prohibitive aluminum level exceeding the accepted standard of 0.20 mg L⁻¹ is described as a serious health concern when the groundwater used for the local water supply. The results of comprehensive field data analysis based on chemometric methods applied to the available monitoring data including 12 groundwater quality parameters are …

Electrochemical Properties Of Crystalline Polymorphs Of Mno2 In Aluminum And Zinc Metal Batteries, Subhadip Pal

Dissertations and Theses

The widespread use of non-renewable fossil fuels has led to societal problems like global warming and climate change. Electrochemical energy storage can enable the integration of renewable energy sources that are inherently intermittent (solar, wind, etc.) into the electric grid, though major advances in cost, cycle life, and safety are necessary to have a global impact on the energy landscape. Both aluminium (Al) and zinc (Zn) metals are earth abundant, low-cost, safe, and exhibit high coulombic capacities, which make them promising electrode materials for “beyond lithium-ion” battery chemistries. However, the electrochemical feasibility and charge storage mechanisms of alternative Al and …

Improving The Delivered Specific Impulse Of Composite Rocket Propellant Through Alteration Of Chemical Composition: Methodology And Parameters For Characterization Of Propellant And Validation Of Simulation Software Common To The Amateur Rocketry Community, Isaac O'Brien, Austin Ryan

Williams Honors College, Honors Research Projects

In this study, two solid composite rocket propellants were designed utilizing ProPEP, a rocket propellant formulation software common in the amateur and hobby rocketry communities. The two propellants were designed to optimize specific impulse relative to a literature propellant designed by 1020 Research Labs. The literature propellant was also tested in order to validate the design of experiment as well as the mixing and testing procedures. All three propellants, which includes the literature propellant RCS-P, and the two novel propellants AKR-P1 and AKR-P2 were characterized with static tests. The results of the static tests provide data on propellant performance and …

Prevention Of Harmful Algal Blooms By The Mitigation Of Phosphorus Nutrient Loading Via Filtration By Steel Wool And Activated Carbon, Ronald Simpson, Sara Kidd, Samantha Zidd

Williams Honors College, Honors Research Projects

Harmful Algal Blooms (HABs) are a devastating ecological and economic consequence of the abundance of nutrient-rich agricultural runoff entering aquatic ecosystems (Baker et al. 2014). Bio-available phosphorus from synthetic fertilizers is one of the major nutrients contributing to this global issue. Previous studies indicated that dissolved phosphorus can be removed from an aqueous environment when passed through a composite mixture of granular steel wool particles and activated carbon (Erickson, Gulliver, and Weiss, 2007). In this project, we conducted experiments using higher quality concentration measurements to determine what grades of steel wool (SW-0000, SW-000, SW-00) and types of activated carbon (granulated …

Understanding Effects Of Engineering Outreach On Elementary Students, Thomas Cobb

Williams Honors College, Honors Research Projects

Currently, there is a desire to increase engineering understanding held by elementary students. As such, there needs to be a way to stimulate not only engineering, but other science, technology, engineering, and mathematics (STEM) topics in a young student’s lifestyle. One way to emphasize the importance of STEM while also showing how fun it can be is through different hands on activities led by individuals partaking in undergraduate studies or the industry. While having the students participate in the activities, it is important to understand what the students are learning and how the activity overall is viewed. With the help …

Investigation Of The Synthesis And Optoelectronic Properties Of Ultrasmall Cdse Quantum Dots, Megan Webster

Dissertations and Theses

Traditional, or 1^st generation, solar cells have a theoretical upper limit of 33% power conversion efficiency based on the thermodynamic limitation of the single p-n junction cell design. This limitation is known as the Shockley-Queisser limit and methods to design solar cells to circumvent it have been creative, with a significant part of the field focused on quantum dot (QD) based systems. With theoretical efficiencies ranging between 44 and 67% for one sun concentration, QD solar cell designs are clearly superior to the limits of 1^st generation solar cells. However, maximum achieved efficiencies for QD-based designs are far …