Engineering Commons^™

Recovery Of Degraded Ni-Rich Nmc811 Particles For Lithium-Ion Batteries, Han Yu, Yan Gao, James Kirtley, Gabriel Borgmeyer, Xiaoqing He, Xinhua Liang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Nickel-rich cathode materials attract a lot of attention due to their high energy density. However, their sensitivity to air and moisture hinders their practical applications. Exposing Ni-rich NMC in the air will produce by-products that are not conducive to lithium-ion transmission. Water washing can be used to remove by-products on the surface, but it can also introduce new problems, such as the generation of NiO on the particle surface, which will reduce the electrochemical performance of the material. In this study, Al₂O₃atomic layer deposition (ALD) was applied on degraded NMC811 particles to recover the electrochemical performance …

Repair And Strengthening Of Concrete Bridges Using Ultra-High-Performance Concrete (Uhpc), Antony Kodsy

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Reinforced/Prestressed concrete bridges are subjected to environmental effects that cause premature deterioration and require structural repair and strengthening during their service life. Currently 42% of bridges in the United States are at least 50 years old, and 7.5% of them are structurally deficient and need to be repaired/strengthened. Recently, new repair and strengthening techniques using Ultra-High-Performance concrete (UHPC) have shown a great potential with respect to performance, economy, and speed. UHPC is a new class of concrete that has mechanical and durability properties that are far superior to those of conventional concrete (CC). In addition, UHPC offers several advantages compared …

Inactivation Of Salmonella In Black Peppercorn By Fluidization With Hydrogen Peroxide Vapor, Edel Summers

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The purpose of the present study was to assess the effectiveness of hydrogen peroxide vapor (HPV) at inactivating Salmonella inoculated in whole black pepper when used as fluidizing gas media. HPV treatment was conducted at two different temperatures (45°C and 60°C) and two dwell times (30 min and 60 min). Microbial reduction and residual hydrogen peroxide were measured at three storage times: 0 h (immediately after treatment), 24 h and 48 h post-treatment. The effect of HPV on the quality of whole black peppercorn was evaluated 48 h post-treatment based on changes in piperine content, total phenolics, antioxidant activity, total …

Connecting Process Performance And Microbial Community Dynamics During Anaerobic Wastewater Treatment To Improve Microbial Resource Management, Jessica Anne Deaver

All Dissertations

Anaerobic wastewater treatment technologies produce renewable energy and recover resources through microbial conversion of organics. Anaerobic digestion is commonly utilized for municipal wastewater sludge treatment, and co-digestion with other organic-rich substrates like fats, oils, and grease (FOG) can improve methane production. Methane can be captured for combined heat and power production. Microbial electrochemical cells (MXCs) convert organic waste to electrical current to produce electricity or other valuable chemicals. Both these technologies would benefit from understanding the microbial conversion processes more thoroughly. FOG co-digestion sometimes inhibits rather than bolsters methane production. MXCs have potential for blackwater (urine and feces) treatment in …

Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano

All Theses

Toxoplasma gondii is a pathogenic microorganism that is currently a threat to public health. Understanding the fate and transport of T. gondii through the soil and groundwater is vital in determining the risk it poses to water resources and human health. The physico-chemical interactions between the groundwater and the bio colloid within an aquifer will dictate its mobility and its ability to infect humans. This research examines how various naturally occurring groundwater chemistries containing organic compounds and monovalent and divalent salt solutions will alter the fate and transport of T. gondii. Solutions containing various concentrations of humic acid, fulvic …

Toward Sustainable Urban Food Production: Integrating Hydroponic Cultivation With Wastewater Reuse, Amanda Tan

All Theses

The growing crisis of freshwater scarcity together with the increasing global food demand directs attention to the need for alternative water sources for agriculture. The research presented here engages this need by carrying out indoor cultivation of food crops in Nutrient Film Technique (NFT) hydroponic systems using residential wastewater. Randomized single factor experimental designs were used to investigate the physiochemical and microbiological makeup of the hydroponic nutrient solution throughout the cultivation cycle and their relationship with different plant development parameters.

For agricultural wastewater reuse to be of low risk to human health there must be some advancement in pathogen monitoring …

3d Volumetric Mapping Of Tissue Properties Via A Catheter-Scale Microendoscope Imaging System, Andrew Stark

Biomedical Engineering Undergraduate Honors Theses

The study of tumor microvasculature is an important area of interest for research and clinical communities; however, there are significant limitations in the clinical characterization of the tumor microenvironment. Optical methods offer quantitative real-time measurement of tissue structure and perfusion and can be miniaturized for deployment endoscopically into previously inaccessible locations. However, conventional optical methods (i.e., optical coherence tomography, white light endoscopy, etc.) gives limited information about tissue perfusion while the diameter of various optical probes along with the complexity of scanning mechanisms make it difficult to access certain areas. In this study, a new technique for characterizing the tumor …

Erythrocyte Deformability In Response To Glucose Using Liquid Crystals, Jayden Goff

Biomedical Engineering Undergraduate Honors Theses

The worldwide prevalence of diabetes mellitus is rapidly increasing with about 9.3% of the adult population living with the disease. People with diabetes have trouble regulating their blood glucose levels which typically leads to hyperglycemia. Under normal physiological conditions, erythrocytes can undergo deformations in response to shear stress when passing through capillaries with a smaller diameter. Poorly managed hyperglycemia can lead to the glycosylation of erythrocyte membrane proteins and hemoglobin. This glycosylation leads to increased rigidity of the cells along with decreased deformability in response to mechanical stress; therefore, these cells have a higher susceptibility of getting stuck in the …

Clot Analogs For The Development Of Improved Treatment Methods In Ischemic Stroke, Charles A. Rieth

Biomedical Engineering Undergraduate Honors Theses

According to the CDC, nearly 800,000 individuals experience stroke each year in the United States [1]. Greater than 70% of strokes are of ischemic etiology and involve the occlusion of key arteries in the cardiovascular system [2]. Tissue plasminogen activator (IV-tPA) is the current gold standard for thrombolytic approaches [3]; however, this therapeutic is only effective between 3 and 4.5 hours from the patient’s last know well [4]. As a result, less than 5% of acute ischemic stroke patients receive IV-tPA. In order to increase the viability of AIS treatment as a whole, it is essential that thrombolytic techniques are …

Development Of A Novel Sensor For Soil Moisture's Profile, Toan Canh Nguyen

Electrical Engineering Theses - Archive

Monitoring of soil’s water content has been an important part of the irrigation system in farming, regional resources development, rainfall detection as well as disaster prevention. There has been studies and developments in this area over the decades. However, most of the works are focused on sensing the soil as a homogeneous medium, which does not accurately reflect the heterogeneous structure of soil. Works on multi-layer soil sensing have been researched and developed. Though, the current design is complex, not easy to produce and assemble. This work presents a novel low-cost and simple soil sensor design to detect the soil’s …

Nonlinear Optical Microscopy Assessment Of Tissue Structure And Chondrocyte Viability Of Articular Cartilage, Michael Le

All Theses

Articular cartilage functions to protect the ends of bones by providing a surface that can withstand compressive forces and minimize friction during movement. Collagen fibers form the organizational backbone of the extracellular matrix (ECM) in cartilage. Proteoglycans within the ECM function to retain water and provide the tissue with the swelling pressure needed to withstand compressional forces. Chondrocytes, the only type of cell found in articular cartilage, produces these collagen fibers and proteoglycans to maintain the tissue structure and function. Significant injuries to articular cartilage can damage the chondrocytes and disrupt their ability to maintain homeostasis in the tissue. Therefore, …

Localized Intra-Arterial Drug Delivery Device For Stroke Treatment, Benjamin Yip

Biomedical Engineering Undergraduate Honors Theses

Strokes are one of the leading causes of death and long-term disability in the United States, and according to the Centers for Disease Control and Prevention more than 795,000 people experience a stroke every year. Around 87% of all strokes are ischemic strokes making it the most common form of stroke. While ischemic strokes are treatable, current devices and methods still result in high mortality rates and high risks of hemorrhaging after treatment. The aim of this study is to design and test a prototype of a novel device for the localized delivery of thrombolytics to treat ischemic strokes. The …

Simulation Of Li Dendrite Inhibition In Lithium Battery By Phase-Field Method, Yao Ren

Material Science and Engineering Dissertations - Archive

Lithium (Li) dendrite growth poses serious challenges for the development of Li metal batteries which also stops the footsteps of human utilizing the environment-friendly new power source. Replacing liquid electrolyte with solid electrolyte can not only inhibit the dendrite growth by mechanical suppression, but also introduce more possibilities to the electrochemistry of battery. However, the underlying mechanism is still not fully understood, and most theoretical works focus on pure liquid electrolyte, ignoring the mechanical strain effects. Here we developed a phase-field model which simulates the Li dendrite growth to study the competition between diffusion and deposition rates, the pure elastic …

Integrating Fire Responses To Combat Wildfires, Jonathan Leonard Badal

Electrical Engineering

Each year wildfires cause significant loss of property, worsen people’s health, and destroy multiple ecosystems. On average, a wildfire season costs anywhere from 7.6-62.8 billion dollars due to fire containment, repair, and restoration [1]. It can take decades to recover from the crippling loss of land and take even longer to fully restore it. However, with the implementation of a robust early detection system, these losses can be significantly reduced. The current process for identifying wildfires involves visual identification, phone call alerts, and media tools primarily driven by park rangers and public reporting. Unfortunately, this system is not preventative and …

Additive Manufacturing Of Variable Contrast Computed Tomography Anatomical Phantoms Using A Single Feedstock In Fused Filament Fabrication, Cory J. Darling

LSU New Orleans Theses and Dissertations

Anatomical phantoms used in biomedical education and training benefit greatly from Fused filament fabrication’s (FFF) ability to rapidly produce complex and unique models. Current materials and methods used in FFF have limited ability to accurately produce phantoms that can mimic the radiological properties of multiple biological tissues. This research demonstrates that the CT contrast of FFF produced models can be modified by varying the concentration of bismuth oxide in acrylonitrile butadiene styrene (ABS) filaments and a tunable CT contrast that mimics the CT contrast ranging from fatty tissue to cortical bone using a single composite filament without introducing artificial image …

Towards Highly Sensitive Capacitance Measurements Of A Quantum Anomalous Hall Phase In Van Der Waal Heterostructures, Kayla Cerminara

UNLV Theses, Dissertations, Professional Papers, and Capstones

One of the pioneering achievements in condensed matter physics of the 20th century is the observation of the quantum Hall e↵ect (QHE) in which the Hall resistance in a two-dimensional (2D) sample takes on quantized values in the presence of a strong perpendicular magnetic field. The precise quantization of the hall resistance to one part in a billion has provided a practical, worldwide resistance standard. A long-standing goal has been to realize a similar state of matter but without the need of a strong quantizing magnetic field. The quantum anomalous Hall e↵ect (QAHE) is such a state that is predicted …

Modeling And Analysis Of Subcellular Protein Localization In Hyper-Dimensional Fluorescent Microscopy Images Using Deep Learning Methods, Yang Jiao

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hyper-dimensional images are informative and become increasingly common in biomedical research. However, the machine learning methods of studying and processing the hyper-dimensional images are underdeveloped. Most of the methods only model the mapping functions between input and output by focusing on the spatial relationship, whereas neglect the temporal and causal relationships. In many cases, the spatial, temporal, and causal relationships are correlated and become a relationship complex. Therefore, only modeling the spatial relationship may result in inaccurate mapping function modeling and lead to undesired output. Despite the importance, there are multiple challenges on modeling the relationship complex, including the model …

Effects Of Distributed Energy Resources On The Bulk Electric System, Stryder Loveday

UNLV Theses, Dissertations, Professional Papers, and Capstones

The traditional power grid was designed with a centralized resource distribution in mind, with a relatively small number of large power generation facilities supplying the vast majority of load. With recent efforts to further diversify the power grid as well as an increased interest in renewable energy sources, there has been an unprecedented amount of new DistributedEnergy Resources (DERs) added to the grid within the last decade. This often heavily influences the local demand where these resources are installed, often causing power to flow in ways not anticipated by the original design of the grid. This thesis reviews the potential …

Carbon Fiber Coil Spring Characterization And Manufacturing, Cooper Madrazo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Helical coil springs are used in many mechanical design applications including industrial machines, devices, and vehicle suspension systems. It is desirable to minimize the weight of vehicle suspension systems as this can improve performance and handling. Most vehicle suspension coil springs are made from solid steel alloys or other metallic materials. Significant weight savings could be achieved if the metallic material were replaced by high performance fiber reinforced polymer composites. However, the coil spring geometry is a difficult manufacturing challenge for composite materials. The goal of this thesis was to investigate efficient and low-cost manufacturing methods to produce light-weight polymer …

Fuel Injector Design Of A Hypersonic Jet Engine Using Computational Fluid Dynamics, Melissa Rose Mercado

UNLV Theses, Dissertations, Professional Papers, and Capstones

The development of hypersonic airbreathing engines, such as a supersonic combustion ramjet, or scramjet, are implemented for flight Mach numbers over 5 where combustion must occur in supersonic conditions. The advancement of scramjet propulsion has led to favored usage over rocket propulsion systems for in atmosphere applications due to their lighter weight, higher specific impulse, and greater maneuverability [1]. The combustor section of a scramjet engine houses the fuel injectors. Fuel is injected into the supersonic flow with the main objective of achieving rapid and thorough fuel-air mixing because the residence time in the combustion chamber has a timescale of …

Behavior Of Axially-Restrained Reinforced Concrete Beams Under High Sustained Loads, Ghazaleh Mehdikhan Laleh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Following column failure in a reinforced concrete (RC) frame structure, a progressive collapse may result if the beams supported by the failed column cannot generate an alternate path to carry the redistributed gravity loads. Past studies of the collapse resistance of RC frame beams were limited to their short-time load-carrying capacity. Axially restrained frame beams experience a compressive arch action as a beneficial load-resisting mechanism not considered in a conventional structural design. Due to the compressive arch action, the column failure may not cause an immediate collapse; however, gravity loads still act on the damaged structure, inducing high sustained stresses …

Viability Of Energy And Fuel Sources For Interstellar Travel; Design And Feasibility Of The Construction Of Manned Interstellar Space Shuttles, Lukas Mittelman

UNLV Theses, Dissertations, Professional Papers, and Capstones

The importance of proving the viability of interstellar transport and addressing its potential hazards and pitfalls is immense. If we do not look toward the future and examine what could be waiting for us, we are doing our children, our children’s children, and so on, a disservice. Here we must attempt to lay the groundwork for our future scientists, engineers, and adventurers. Asking and answering questions like, which propulsion and energy systems must we incorporate to send us through the cosmos? Will we utilize technologies known today, such as fossil fuel rockets, fission or fusion rockets, and antimatter drives (pion …

Development Of Uav-Based Rail Track Geometry Irregularity Monitoring And Measuring Platform Empowered By Artificial Intelligence, Lihao Qiu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rail tracks need to be consistently monitored and inspected for problems associated with rust, deformation, and cracks that, at their worst, can cause catastrophic train derailments. Many non-destructive testing approaches have been explored and extensively utilized to help inspect rails’ health, but most of them require intensive human power and/or heavy sensor systems (e.g. total stations, manual/car-mounted trolly, etc.) that are not efficient or convenient to cover a long range of rails and may interfere with the normal operation of trains.In light of the rapid development of unmanned aerial systems/vehicles (UAS’s/UAVs) and high definition photographic and optical distance measuring sensors, …

A Performance Guide For Four Songs By Francisco Mignone, Amanda Mara Rizzotto Vidal Pessoa

UNLV Theses, Dissertations, Professional Papers, and Capstones

The scope of this document is to demonstrate the richness and diversity to be found in the art song genre from countries outside of the standard repertoire, specifically focusing on the Brazilian composer Francisco Mignone. The purpose of this document is to provide performance practice guidelines for four selected pieces by Francisco Mignone: No Meio do Caminho (1938), Pregão (1947), Si eu sei o que é saudade (1976), and Valsa-Vocalise (1972). They exemplify expressions of Brazilian national identity through the music selected. Furthermore, it provides a brief background on the composer and his compositional style phases, and context for the …

New Mathematical Models For Acoustic Insertion Loss Of Fiberglass Lining In Hvac Duct, Michael Anthony Schwob

UNLV Theses, Dissertations, Professional Papers, and Capstones

The design objectives for HVAC air distribution systems are thermal comfort, good indoor air quality, energy efficiency, low construction cost, and appropriate indoor noise levels. The last objective requires that the designer can predict the attenuation of sound transmitted through an air duct. One form of attenuation commonly introduced to an air distribution system to achieve interior noise criteria is fiberglass liner. Past research has been conducted to obtain reliable and accurate insertion loss (IL) data for duct with fiberglass liner. Empirical efforts have relied on limited data sets. Computational efforts have produced numerical models that are not practical for …

Climate Change Impacts And Engineering Solutions, Dawson Oakley

Biological and Agricultural Engineering Undergraduate Honors Theses

With climate change entering the forefront of global issues, the need for sustainable practices that can provide for human welfare, social and economic development, and health has become more urgent than ever. Despite the recent increase in climate change impacts around the world, many people are still unaware of the severity of the situation. Changing public perception of these issues is the first step in enacting change and increasing accessibility to this information plays an important role.

Much of the information people consume today comes in the form of video, and it can be an effective tool to change knowledge …

Modeling Leaf Area Index And Canopy Height Using Growing Degree Days, Ellie J. Kuhn

Biological and Agricultural Engineering Undergraduate Honors Theses

As the global population increases and food security is recognized as a critical issue, crop growth prediction models help ensure the sustainability of reliable food sources. Using a prediction model based on temperature and simple, measurable field parameters, e.g., Leaf Area Index (LAI) or Canopy Height (H_can), may allow farmers and others to intervene mid-season with fertilizer, irrigation, or other inputs to obtain a better harvest.

This study aims to create a general model that could predict LAI and H_can values for numerous rice varieties using Growing Degree Days (GDD) as the time scale. The models use …

Exploring The Effects Of Varied Land Use On Elemental Concentrations Within Streams, Logan Jennings

Biological and Agricultural Engineering Undergraduate Honors Theses

It is well documented that human activity influences the chemistry of surrounding waters. As such, it is possible that there is a link between land use within a watershed and the chemical composition of the stream. The objectives of this study are to determine if varied land use does affect the concentrations of macronutrients and trace elements present in the streams of Northwest Arkansas, and if so, to determine what extent urban and agricultural development are responsible for these changes. Water samples were collected across 19 streams in the Northwest Arkansas region between January and March of 2022. Water samples …

Potato Processing In The Home: Sustainability And Nutritional Impacts, Aubin Payne

Biological and Agricultural Engineering Undergraduate Honors Theses

Potatoes are the world's fourth most consumed crop. Their versatility and long shelf-life make them a staple food for millions of people worldwide. Still, the increasing consumption of highly processed potato products in developed countries has damaged the public's appreciation of potatoes as a valuable source of essential nutrients. Additionally, as public awareness of environmental sustainability increases, the average consumer is more likely to value processing methods that mitigate environmental damage.

Researchers simulated several home storage and processing conditions to find out how nutrition and environmental impact are affected by the home processing timeline. Then, a nutrient analysis, life cycle …

Sensory Comparison Of Beer Carbonated Using Forced Carbonation And The Carbo Rock-It, Michala Smith

Biological and Agricultural Engineering Undergraduate Honors Theses

Craft brewing is a growing market which represents over 12% of beer produced in the United States. Dr. G Scott Osborn, PE invented the Carbo Rock-It™ to improve the carbonation process for craft breweries. The invention allows for shorter carbonation time and uses less CO₂, saving companies money and time. Because of the lack of gas losses through bubbling, Osborn theorized that the Carbo Rock-It could also prevent the “stripping of the nose” that can occur in traditional forced carbonation. Existing research supports the mechanism, as beer flavor and aroma volatiles have been detected during the release of …