Engineering Commons^™

Synthesis Of Geopolymer Using Coal Fly Ash And Corn Stover, Anu Paneru

Master's Theses

The development of each nation is dependent on its infrastructure, and nations are competing with others in infrastructure, especially in the construction of roadways, since they play a vital role in the economic and social development of the nation. The conventional materials used for road construction are cement and asphalt, which pose significant environmental challenges. This thesis explores the potential of fly ash (FA) and corn stover (CS) in synthesizing geopolymer, as an alternative material for the construction of roads. The study examines the impact of FA and CS percentages and the particle sizes of CS on the compressive strength, …

Comparing Proliferation Rates And Collagen Production Of Cells Treated With Cuhars, Katie Elizabeth Mckenzie

Master's Theses

Cartilage is the padding in joints that protects the bones and aids in motion. Problems with the cartilage in the knee can be caused by mechanical damage or diseases like osteoarthritis. Chondrocytes make cartilage. The objective of this study is to determine the doubling time of chondrocytes per passage. I also want to determine the base amount of collagen-II created by chondrocytes as they age. I also want to determine how long it takes CuHARS to break down in different cell medias. Chondrocytes, human dermal fibroblasts, and CRL 2303 cells were grown and cultured for over a year. During that …

Multi-Scale Computational Modeling Of Metal/Ceramic Interfaces, Abu Shama Mohammad Miraz

Master's Theses

Multi-scale atomistic calculations were carried out to understand the interfacial features that dictate the mechanical integrity of the metal/ceramic nanolaminates. As such, first principles density functional theory (DFT) calculations were performed to understand the electronic and atomistic factors governing adhesion and resistance to shear for simple metal/ceramic interfaces, whereas molecular dynamics (MD) simulations were performed to observe the impact of interfacial structures, such as misfit dislocation network geometries and orientation relationships, on interfacial mechanical properties.

For the DFT investigation, we choose metals with different crystal structures, namely - Cu (fcc), Cr (bcc) and Ti (hcp) along with a variety of …

Valorization Of Secondary Agriculture Residues, Narendra Kumar

Master's Theses

Secondary agriculture residues have the potential to be major contributors as resources for energy and sustainably sourced materials production. Separating secondary agricultural residues, which have already been transported to processing centers, into individual biomass components could convert these wastes into bioproducts. Many types of pretreatments to achieve this separation involve chemicals that are hazardous for the environment. Several deep eutectic solvents (DES) that are biocompatible have been investigated for their ability to deconstruct rice hulls and sugarcane bagasse. Mass yield, enzymatic hydrolysis of the pretreated biomass, fiber analysis, and Fourier transform infrared spectroscopy have confirmed that the DES formic acid:choline …

Glial Endothelial Brain Cell Co-Cultures For Testing Signaling Response And Delivery Of Novel Materials Across Blood Brain Barrier, Neela Prajapati

Master's Theses

The brain accounts for 20% of overall energy metabolism in the body though it just comprises 2% of the total body mass but has a limited capacity of storing energy unlike other critical organs in the body such as the heart and liver. This energy along with oxygen and nutrients is supplied by cerebral blood flow (CBF), any interruption of which can cease the brain function within seconds with a potential irreversible neuronal injury, within minutes. Vascular cells along with astrocytes and neurons are a part of a recently developed concept known as the Neurovascular Unit responsible for Neurovascular coupling …

Lateral Torsional Buckling Resistance Of Continuous Steel Stringers In Existing Bridges, Dinesha Malky Kuruppuarachchi Kuruppuarachchi Appuhamilage Don

Master's Theses

Some of the Louisiana’s bridges built in the 1950s and 1960s used two-girder or truss systems, in which floorbeams are carried by main members and the continuous (spliced) stringers are supported by the floorbeams. The main members are either two edge (fascia) girders or trusses. When the flexural capacity of continuous stringers is calculated, the moment gradient factor (Cb) is not accurately calculated considering the lateral torsional buckling (LTB) at the negative moment section. In particular, the bracing effect of the non-composite concrete deck is not accounted for, and as a result, the current practice has underestimated the LTB strength …

Dispersion Of Spherical Silicon Dioxide Nanoparticles In Poly(Styrene-B-Methyl Methacrylate) Diblock Copolymer Domains, Joshua C. Obinwa

Master's Theses

Polymer-nanoparticle hybrids are nanomaterials in which the unique properties of the nanosized structures can be precisely tuned by choosing an appropriate combination of the polymer and the nanoparticle. However, nanoparticle dispersion in a polymer is challenging due to the aggregation tendency of nanoparticles. To improve nanoparticle dispersion and control the location of nanoparticles in block copolymer assemblies, the nanoparticle surface is modified with surface ligands compatible with the block copolymer. In this thesis, hydroxyl-terminated poly(styrene-b-methyl methacrylate) (PS-b-PMMA) was utilized to functionalize the nanoparticle surface, covalently anchoring the hydroxylterminated end of the polymer onto the silicon dioxide nanoparticles. The silicon dioxide …

Electrochemical Detection Of Reactive Oxygen Species Via A Platinum Microelectrode Array, Victor M. Carriere Jr.

Master's Theses

Oxidative stress, an excess of endogenous or exogenous reactive oxygen species (ROS) in the body, is closely aligned with inflammatory responses. ROS such as hydrogen peroxide, superoxide, and radical hydroxyl ion serve essential functions in fighting infection, but chronic elevation of these species irreversibly damages cellular components. Given the central role of inflammation in a variety of diseases, including Alzheimer’s Disease, atherosclerosis, and rheumatoid arthritis, a low-cost, extracellular, non-invasive assay of ROS is needed.

This work reports the use of a platinum microelectrode array (Pt MEA)-based ceramic probe to detect time- and concentration-dependent variations in hydrogen peroxide (H2O2) production by …

Pretreatment Of Loblolly Pine Tree Toppings (Needled) Using Dess, Prathima Gujjula

Master's Theses

Contemporary industrial development and swift urbanization require environmentally sustainable energy sources. Ethanol made from biomass provides unique environmental and economic strategic benefits and can be considered a safe and clean liquid fuel alternative to fossil fuels. Ethanol’s significant advantages, such as low cost, biodegradability, and abundance, make the application of biomass for production of biorenewable energy favorable. However, biomass must be subjected to pretreatment processes to liberate the components needed for effective enzymatic hydrolysis that converts cellulose to sugars prior to fermentation to create biofuel. Production of valueadded co-products besides biofuels, through coordinated bio refinery processes, requires selectivity during pretreatment. …

Molecular Weight And Heating Value Of Lignin Extracted Using Deep Eutectic Solvent., Ekugbere Owen Owhe

Master's Theses

The molecular weight of lignin helps us to determine how lignin can be applied accurately in industry. The molecular weight can predict the behavior of lignin, and how it will function when combined with other materials. This thesis discusses how the molecular weight of lignin can be found with gel permeation chromatography (GPC) after acetylation with acetic anhydride and pyridine. Different lignins gave different number average molecular weight and weight average molecular weight values, which were likely due to the biomass source, type of extraction and solubility in the solvent of choice. How the structure of lignin changed after derivatization …

Improving Paper-Based Microfluidic Mixing With The Incorporation Of Flow Disrupting Structures, Hannah C. Green

Master's Theses

Paper-based microfluidic devices provide a light-weight, cost effective platform for diagnostic and analytical testing. The goal of this project is to enhance paper-based microfluidic mixing by incorporating fluid flow disrupting structures (referred to here as rib bones) into the microdevice design to expand the analytical capabilities of paperbased microfluidic devices. The devices are fabricated on Whatman CHR-1 chromatography paper. The devices are designed in SolidWorks and printed using a solid ink printer (ColorQube 8580). The wax is penetrated into the paper to create hydrophobic barrier regions by heating in a convection oven until the wax is fully penetrated. The parameters …

From Experimental Studies To Coarse-Grained Modeling: Characterization Of Surface Area To Volume Ratio Effects On The Swelling Of Poly (Ethylene Glycol) Dimethacrylate Hydrogels, Gabriel Zahm

Master's Theses

Understanding the performance of widely applied nanoscale hydrogel biomaterials is an unmet need within the biomedical field. The objective of this master’s thesis project was to evaluate the effects size and surface area has on the in vivo behavior of nanoscale hydrogels. The hypothesis tested was that at the nanoscale, the increased surface area to volume effects of nanoscale hydrogels play and important role in the overall swelling of hydrogels, such that nanoscale hydrogels swell to a greater degree than their bulk counterparts. To investigate this, the bulk swelling behavior of a series of neutral poly (ethylene glycol) di-methacrylate (PEGDMA) …

Design And Analysis Of A Traveling Wave Fault Locator, Gerald Austin Taylor

Master's Theses

The accuracy of fault location is an integral part of power system operations. Improved fault location can reduce maintenance time, increase efficiency, and save money. When a fault occurs, it sends a disturbance in the current and voltage in each direction at almost the speed of light. This disturbance is called a traveling wave, and can be used to locate faults. In efforts to increase accuracy, the use of traveling wave theory to locate faults has become more popular.

This thesis goes through the process of designing and testing a traveling wave fault locator. The design includes analog and digital …

Metal Related Nanoparticles' Physical Behaviors In Different Physiologica Environments, Muhetaer Tuerhong

Master's Theses

In the past decades, the development of nanotechnology has had tremendous successes in material science. In this technology, the pertinent materials are used at the intermediate scale between individual molecules and their size in the nanometer region(1-100nm) compared to bulk materials. This nanoscale size provides a larger surface area; therefore, nanoparticles would be perfect essential components of nanotechnology. The reduced size of nanoparticles has a larger surface ratio to volume, which can modify their chemical, mechanical, structural, and electrical properties.

In this study, the main goal is to test different metal related nanoparticles, such as CuNPs (Copper nanoparticles), FeNPs (Iron …

A Study Of The Mono-Stable And Bi-Stable Magnetic Spring Based Vibration Energy Harvesters Subject To Harmonic Excitation, Hieu Tri Nguyen

Master's Theses

Continuous improvement in electronics manufacturing has led to the deployment of low-power sensors, which has resulted in an urgent need for developing energy harvesters capable of generating electric power using abundant and free energy sources such as ambient vibrations. The work presented here is motivated by the growing interest in targeting nonlinear energy harvesting through magnetic interactions, which are compatible with ambient vibration energy sources that are often characterized by a broadband frequency spectrum and can be particularly rich with low frequencies. In this work, experimental and theoretical studies were performed to investigate a magnetic- levitation-based vibration energy harvester that …

Spring-Guided Electromagnetic Vibrations Energy Harvester, Ghufran Jaber Aldawood

Master's Theses

In recent years, vibration based energy harvesting techniques showed a promising alternative to power wireless sensor networks (WSN). Billions of low power sensors are currently used widely in wireless sensor networks (WSN) and the Internet of Things environment (IoT). These sensors are currently powered by a traditional power source, i.e. a disposable battery. Vibrations are an abundant source of kinetic energy that can serve as the power source for these sensor nodes. This approach eliminates the necessity for frequent battery replacement due to their short-life span and hazardous disposal process. The adverse and irreversible effect from the disposal of these …

Investigating The Rapid Curing Possibility Of Geopolymer Concrete, Ashlesh Banjara

Master's Theses

Recent studies of heat-cured fly ash based green geopolymer concrete have shown its suitability for fabrication of structural members. Fabrication of these structural members requires continuous moderate heating (145°F) for 24 hrs, and an oven essential, for a large member can quickly turn into an energy guzzler, potentially eliminating the green credentials of the product. The proposed research involves the development of a frontal polymerization (FP) method that achieves rapid curing of geopolymer at ambient condition after short-term heat application. Initial work shows thermal FP in geopolymer is a possibility and might be a solution to the problem. The process …

Surface Engineering Solutions For Immersion Phase Change Cooling Of Electronics, Brendon M. Doran

Master's Theses

Micro- and nano-scale surface modifications have been a subject of great interest for enhancing the pool boiling heat transfer performance of immersion cooling systems due to their ability to augment surface area, improve wickability, and increase nucleation site density. However, many of the surface modification technologies that have been previously demonstrated show a lack of evidence concerning scalability for use at an industrial level. In this work, the pool boiling heat transfer performance of nanoporous anodic aluminum oxide (AAO) films, copper oxide (CuO) nanostructure coatings, and 1D roll-molded microfin arrays has been studied. Each of these technologies possess scalability in …

Effects On Strength And Corrosive Characteristics Of Hardened Cement Paste Using Rice Husk And Sugarcane Bagasse, Travis D. Garrett

Master's Theses

Cement is one of the most used building materials in the world. The production of ordinary Portland cement contributes to the release of harmful greenhouse gasses. In an effort to reduce these emissions, different materials are being evaluated for their use as partial replacements for ordinary Portland cement. Rice husk and sugarcane bagasse are agricultural waste products and large amounts of these are currently landfilled, making them inexpensive and available. When combusted at high temperatures they form rice husk ash and sugarcane bagasse ash that have pozzolanic characteristics. The high silicon dioxide in these products makes them good options to …

Metal Segregation During The Solidification Of Titanium-Aluminum Alloys For 3d Printing Applications, Jwala Parajuli

Master's Theses

Titanium-Aluminum alloys are one of the widely used alloys in multiple engineering applications. They are highly preferred in Selective Laser Melting (SLM) processes due to their low density, high melting temperature, and good strength. Segregation occurs during the solidification of most alloys and produces a non-uniform distribution of atoms. In SLM, segregation may depict the type of adhesion between the two deposited interfacial layers and the strength between the interphase between an already solidified layer and a new one, and overall, the quality of the printed part. In order to avoid segregation, the understanding of the segregation behavior at atomistic …