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2024

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Full-Text Articles in Materials Science and Engineering

Experimental Study On Performance Of Cast Asphalt Mixture Basedon Dry Modification, Wang Ming, Li Bo, Bao Guangzhi, Hu Deyong Jan 2024

Experimental Study On Performance Of Cast Asphalt Mixture Basedon Dry Modification, Wang Ming, Li Bo, Bao Guangzhi, Hu Deyong

Journal of China & Foreign Highway

Cast asphalt mixture is the most widely used material for the pavement of long-span steel bridge decks, and the special asphalt binder cannot be produced and used in small batches. The wet modification process is obviously not suitable for the production of the cast asphalt mixture during the operation and maintenance period. In this paper, according to the requirements of cast asphalt mixture and its binder, combined with the requirements of the dry modification process, the developed direct injection modifier was employed to conduct the mix design of cast asphalt mixture and tests of the fluidity, penetration and increment, low-temperature …


Kinetic Applications Of Smart Materials In Architecture: A Descriptive Analysis, Youssef Elkhayat Jan 2024

Kinetic Applications Of Smart Materials In Architecture: A Descriptive Analysis, Youssef Elkhayat

Journal of Engineering Research

In recent years, many smart materials for architectural applications have been invented. Some smart materials can adapt and interact with the surrounding environment and its variants, whether temperature, humidity, daylight or electric current. Smart material changes its shape without any need for assistance, and it can return to its original state without any significant deformation in shape with the end of the external influence. The invention of smart materials stimulated several architects and facade designers to consider using them in various architectural applications such as sun shading, sun breakers, and windows, significantly impacting the concept and technology of movement in …


Hanford Low-Activity Waste Vitrification: A Review, José Marcial, Brian J. Riley, Albert A. Kruger, Charmayne E. Lonergan, John D. Vienna Jan 2024

Hanford Low-Activity Waste Vitrification: A Review, José Marcial, Brian J. Riley, Albert A. Kruger, Charmayne E. Lonergan, John D. Vienna

Materials Science and Engineering Faculty Research & Creative Works

This Paper Summarizes the Vast Body of Literature (Over 200 Documents) Related to Vitrification of the Low-Activity Waste (LAW) Fraction of the Hanford Tank Wastes. Details Are Provided on the Origins of the Hanford Tank Wastes that Resulted from Nuclear Operations Conducted between 1944 and 1989 to Support Nuclear Weapons Production. Waste Treatment Processes Are Described, Including the Baseline Process to Separate the Tank Waste into LAW and High-Level Waste Fractions, and the LAW Vitrification Facility Being Started at Hanford. Significant Focus is Placed on the Glass Composition Development and the Property-Composition Relationships for Hanford LAW Glasses. Glass Disposal Plans …


Thermo-Photo Catalytic Anode Process For Carbonate-Superstructured Solid Fuel Cells, Hanrui Su, Yun Hang Hu Jan 2024

Thermo-Photo Catalytic Anode Process For Carbonate-Superstructured Solid Fuel Cells, Hanrui Su, Yun Hang Hu

Michigan Tech Publications

Converting hydrocarbons and greenhouse gases (i.e., carbon dioxide, CO2) directly into electricity through fuel cells at intermediate temperatures (450 to 550 °C) remains a significant challenge, primarily due to the sluggish activation of C-H and C=O bonds. Here, we demonstrated a unique strategy to address this issue, in which light illumination was introduced into the thermal catalytic CO2reforming of ethane in the anode as a unique thermo-photo anode process for carbonate-superstructured solid fuel cells. The light-enhanced fuel activation led to excellent cell performance with a record-high peak power density of 168 mW cm-2at an intermediate temperature of 550 °C. Furthermore, …


Balsa Bridge, Caleb T. Lovett Jan 2024

Balsa Bridge, Caleb T. Lovett

All Undergraduate Projects

The problem presented throughout this report was to create a small-scale bridge made entirely out of balsa wood and glue, that could withstand substantial force, as well as perform a lifting/lowering cycle. Other requirements associated with the bridge were properties of weight, deflection, size, and shape. This problem presented a challenge that tested the mathematical side of engineering, being strongly reliant on statics, mechanics of materials, and mechanical design analyses.

To approach this problem, the first step was to complete in depth calculations of the chosen design. With this done, manufacturing and assembly was able to be completed. With a …


Hempcrete Curtain Walls, Anh Bui Jan 2024

Hempcrete Curtain Walls, Anh Bui

2024 Awards for Excellence in Student Research and Creative Activity - Documents

This research aims to scrutinize the performance, durability, and viability of hempcrete in curtain wall applications—an exploration critical to advancing sustainable construction practices. Comprising hemp hurds and lime binders, hempcrete stands as an emerging sustainable building material with promising ecological benefits. Despite its potential, there exists a notable research gap concerning its application in curtain walls, which demand rigorous structural and weatherproofing standards. The primary objective is to subject full-scale hempcrete curtain wall assemblies to ASTM standard test methods, comparing their performance with conventional materials like stone and glass. The research hypothesis posits that hempcrete will exhibit satisfactory strength, fire …


Electrochromic Polymers: From Electrodeposition To Hybrid Solid Devices, Haradou Sare, Dongmei Dong Jan 2024

Electrochromic Polymers: From Electrodeposition To Hybrid Solid Devices, Haradou Sare, Dongmei Dong

College of Science & Mathematics Departmental Research

This paper reports on the linear colorimetric and electrochromic (EC) characteristics of electrodeposited polyaniline (PANI) films. This paper also investigates the infrared EC properties of acid-doped PANI films. The electrochemical polymerization method was employed to create a porous and thin PANI film layer onto PET-ITO substrates. This layer was capped with WO3 film to create a gel electrolyte sandwich structure that demonstrates the compatibility of PANI films with cathodic WO3 films in full devices. The electrodeposition of the film was fabricated by applying different voltages and time, with the optimal film quality achieved with the 1.7 V voltage and a …


Research Trends And Impact Report On Aggregation-Induced Emission (Aie), 2001-2021, Elsevier Analytical Services Jan 2024

Research Trends And Impact Report On Aggregation-Induced Emission (Aie), 2001-2021, Elsevier Analytical Services

Public Reports

Since the concept of AIE was first proposed in China in 2001, it has gradually grown to a field of science that attracts dedicated researchers from around the world. Elsevier's data analytics team used AIE experts' interpretation of current theoretical, technological, and industrial development trends in the field for reference to collect AIE-related global scientific publications (from the Scopus database) to serve as a publication set in the field of AIE. This was undertaken to present, accurately and objectively, the development of AIE research over the past two decades and the latest scientific advancements in the field; to facilitate the …


Predicting Compressive Strength Of Concrete Incorporating Fly Ash, Blast Furnace Slag, And Superplasticizer Using Machine Learning Techniques, Muhammad Faisal Yaqub Jan 2024

Predicting Compressive Strength Of Concrete Incorporating Fly Ash, Blast Furnace Slag, And Superplasticizer Using Machine Learning Techniques, Muhammad Faisal Yaqub

2024 REYES Proceedings

Concrete is the second most essential element in the construction industry, and its strength requirements vary based on the specific conditions of each project. However, determining the compressive strength of concrete involves laboratory tests, which wastes a lot of time and money. Researchers have developed machine learning models that predict the compressive strength of cement-based concrete having various mixes. In this research, the compressive strength of concrete incorporating fly ash, blast furnace slag, and superplasticizer is predicted using different machine learning models, namely, Linear Regression, Random Forest Regression, Decision Tree Regression, Extreme Gradient Boosting, Light Gradient Boosting, AdaBoost, and CatBoost …


Deep Learning Based Optical Flow Analysis Of High-Speed Flows, Daniel H. Zhang, Zifeng Yang Jan 2024

Deep Learning Based Optical Flow Analysis Of High-Speed Flows, Daniel H. Zhang, Zifeng Yang

Mechanical and Materials Engineering Faculty Publications

Two-dimensional Rayleigh scattering imaging is utilized to quantify the high-speed flow velocity by employing deep learning based optical flow analysis, along with density fields from Rayleigh scattering intensity profiles.


Amplification-Free Rapid Detection Of Specific Oligonucleotides Through Formation Of Core-Satellite Nanostructures On Solid Substrates, Vineet Kumar Jayakrishnan Jan 2024

Amplification-Free Rapid Detection Of Specific Oligonucleotides Through Formation Of Core-Satellite Nanostructures On Solid Substrates, Vineet Kumar Jayakrishnan

Material Science and Engineering Theses - Archive

A rapid, portable, and highly sensitive method for detecting specific pathogens like Covid-19 would be invaluable for public health and emergency responses. The current standards like PCR and RT-PCR, are incredibly sensitive but also time-consuming, require skilled personnel, and demand substantial lab space. Here, we propose an alternative method capable of detecting specific oligonucleotide sequences within just 3 minutes, using a portable silicon or glass substrate (6 mm x 9 mm). We demonstrated this using 67-mer oligonucleotides with a Covid-19 sequence as a model system, achieving a detection sensitivity down to 1 nM. Our approach involves sandwiching target COVID-19 oligonucleotides …


Investigation Of Bone Structure And Composition Differences In Osteofibrous Dysplasia And Neurofibromatosis Type 1, Farzaneh Fereidouni Jan 2024

Investigation Of Bone Structure And Composition Differences In Osteofibrous Dysplasia And Neurofibromatosis Type 1, Farzaneh Fereidouni

Material Science and Engineering Dissertations - Archive

Abstract

Investigation of Bone Structure and Composition Differences in Osteofibrous Dysplasia and Neurofibromatosis Type 1

Farzaneh Fereidouni, Ph.D.

The University of Texas at Arlington, 2024

Supervising Professor: Harry F. Tibbals

Bone genetic diseases such as Osteofibrous Dysplasia (OFD) and Neurofibromatosis type 1 (NF1) present significant challenges, particularly in children, due to their effects on skeletal homeostasis. This study aims to apply advanced material analysis to elucidate the biological disparities associated with OFD and NF1 bone dysplasia and contribute to developing diagnostic protocols and remediation approaches for these and similar bone disorders.

By employing various analytical methods, including analysis of mineral-to-matrix …


Sub-1k Cold Electron Transport At Room Temperature, Anthony Martinez Jan 2024

Sub-1k Cold Electron Transport At Room Temperature, Anthony Martinez

Material Science and Engineering Dissertations - Archive

Thermally excited electrons at the high-energy tail of the Fermi-Dirac distribution impose fundamental limitations on the performance of solid-state electronic and spintronic devices. For example, the thermally excited electrons obscure the Coulomb blockade essential for single-electron transport. The hot electrons can also overcome the energy barrier of Metal-Oxide-Semiconductor Field-Effect transistors (MOSFETs), causing unwanted leakage currents that lead to excessive power consumption in the integrated circuits. This study investigates an approach in which quantum states are used to manipulate electron tunneling, blocking the transport of thermally excited hot electrons, thereby enabling cold-electron transport at room temperature. Here two heterogeneous quantum wells …


Kissing Bond Assessment In Adhesive Bonded Carbon Fiber Reinforced Composites Using Dielectric Spectroscopy, Minhazur Rahman Jan 2024

Kissing Bond Assessment In Adhesive Bonded Carbon Fiber Reinforced Composites Using Dielectric Spectroscopy, Minhazur Rahman

Mechanical and Aerospace Engineering Dissertations - Archive

The widespread use of fiber-reinforced composites in industries such as space, aviation, automobiles, and construction necessitates the formation of robust composite joints between critical structural components. Although adhesive-bonded joints are superior with improved load distribution and reduced weight, they are often overlooked in favor of bolted joints and mechanical fasteners due to the lack of reliable Non-Destructive Evaluation (NDE) techniques for adhesive-bonded composites. The anisotropic nature of the substrate and the intricate interfacial interactions between the adherend and adhesive material present significant challenges for conventional NDE methods. Moreover, weak adhesive bonds can result from uncontrolled manufacturing parameters, such as accidental …


Experimental Investigations And Optimization Of 3d Printed Cellular Structures For Protection Against Traumatic Brain Injury, Aaron R. Jackson Jan 2024

Experimental Investigations And Optimization Of 3d Printed Cellular Structures For Protection Against Traumatic Brain Injury, Aaron R. Jackson

Mechanical and Aerospace Engineering Dissertations - Archive

Traumatic Brain Injury (TBI) disrupts brain function due to head impacts, blast exposures, and ballistic penetrations. It is a significant cause of mental health issues and disability, particularly among military personnel. Historically, combat helmets were designed primarily to protect against fragments. However, recent data highlights the need for helmets that also protect against blast and blunt impacts. Effective TBI prevention requires helmets that address various energy threats while remaining lightweight. A critical metric in this effort is head acceleration, which is closely linked to injury across different scales of brain damage.

Four lattice structures were 3D printed using Digital ABS …


Synthesis Of Ni-Based Intermetallics By Electrolytic Plasma Processing Of Ti And Ti-Based Alloys, Chuzhong Zhang Jan 2024

Synthesis Of Ni-Based Intermetallics By Electrolytic Plasma Processing Of Ti And Ti-Based Alloys, Chuzhong Zhang

Material Science and Engineering Dissertations - Archive

EPP is an innovative surface modification technique that enables the deposition of metal ions from the electrolyte and their integration with substrate atoms to form intermetallic compound surface layers. EPP offers advantages such as high deposition rates, environmental cleanliness, and operational simplicity. In this study, Ni-Ti intermetallic layers were successfully synthesized on a Ti-6Al-4V substrate using EPP. The properties of the resulting Ni-Ti intermetallic layers were characterized using SEM, EDS, XRD, TEM, nanoindentation, and tribology tests.

This work aims to understand the fabrication mechanism and investigate the effects of various processing parameters on the EPP process. Key factors such as …


Generalizable Fugitive Carrier Method For 3d Printing Of Hydrogels, Hakan Arslan Jan 2024

Generalizable Fugitive Carrier Method For 3d Printing Of Hydrogels, Hakan Arslan

Mechanical and Aerospace Engineering Dissertations - Archive

Hydrogels, with physical characteristics resembling biological soft tissues, hold great potential for bioinspired and biomedical applications. However, using them in additive manufacturing systems has challenges because of their poor mechanical and rheological properties. In response to these challenges, we introduce a fugitive carrier method, a novel and generalizable approach for materials incompatible with pneumatic-based extrusion three-dimensional (3D) printers. Our developed fugitive carrier method allows the 3D printing of a broad spectrum of hydrogel precursors with low viscosity while retaining their inherent properties. This technique has been successfully demonstrated by creating biomimetic structures with anisotropic and programmable systems utilizing temperature-sensitive hydrogel …


Quantitative Modeling Of Micro Discharge And Oxide Growth In Plasma Electrolytic Oxidation Of Titanium, Kingsley I. Ochiabuto Jan 2024

Quantitative Modeling Of Micro Discharge And Oxide Growth In Plasma Electrolytic Oxidation Of Titanium, Kingsley I. Ochiabuto

Material Science and Engineering Dissertations - Archive

Plasma electrolytic oxidation (PEO) has been extensively applied in the past to improve the tribological properties of titanium and its alloys allowing their widespread use in industrial applications. However, the complete PEO mechanism of action remains unclear. While there are several mathematical models providing useful insights into the PEO process, they do not fully incorporate the effect of applied potential on the outcomes of PEO. In this work, we develop an experimentally informed computational model by expanding on the dielectric breakdown model. We incorporate experimental data to extract key parameters, exploring the iterative dependency of the oxide thickness and ionic …


Spray-On Sensor Formulations That Enable Detection Of Physical And Chemical Stimuli, Priyanka Shiveshwarkar Jan 2024

Spray-On Sensor Formulations That Enable Detection Of Physical And Chemical Stimuli, Priyanka Shiveshwarkar

Bioengineering Dissertations - Archive

Polydiacetylene based materials have been used for a variety of liquid phase sensing applications. There remains a need for low cost, easy-to-read gas phase sensors for continuous monitoring of physiological parameters and environmental hazards at work or at home. Such sensors could have applications in everyday life, for example as point-of-care or at home testing devices to enable early detection of disease to reduce healthcare costs. Making accessible and non-invasive technologies for monitoring of health and health risks provides individuals with the ability to be proactive in regard to their health and safety. In other examples, environmental monitoring systems could …


Generating Blood Analog For Laser Induced Fluorescent Particle Image Velocimetry, Chungyiu Ma, Jared Chong, Hang Yi, Zifeng Yang, Luke Bramlage, Bryan Ludwig Jan 2024

Generating Blood Analog For Laser Induced Fluorescent Particle Image Velocimetry, Chungyiu Ma, Jared Chong, Hang Yi, Zifeng Yang, Luke Bramlage, Bryan Ludwig

Mechanical and Materials Engineering Faculty Publications

To mimic blood non-Newtonian viscosity features under designated temperatures from 305 to 315 K, transparent blood analogs were generated by the mixture of xanthan gum and deionized water with fluorescent particles for laser induced fluorescent particle image velocimetry.


Enhancing Scanning Tunneling Microscopy With Automation And Machine Learning, Darian Smalley Jan 2024

Enhancing Scanning Tunneling Microscopy With Automation And Machine Learning, Darian Smalley

Graduate Thesis and Dissertation 2023-2024

The scanning tunneling microscope (STM) is one of the most advanced surface science tools capable of atomic resolution imaging and atomic manipulation. Unfortunately, STM has many time-consuming bottlenecks, like probe conditioning, tip instability, and noise artificing, which causes the technique to have low experimental throughput. This dissertation describes my efforts to address these challenges through automation and machine learning. It consists of two main sections each describing four projects for a total of eight studies.

The first section details two studies on nanoscale sample fabrication and two studies on STM tip preparation. The first two studies describe the fabrication of …


Oxidation Of Additively Manufactured Zrb2–Sic In Air And In Co2 At 700–1000 °C, Marharyta Lakusta, Nicholas M. Timme, Abid H. Rafi, Jeremy Lee Watts, M. (Ming) C. (Chuan) Leu, Gregory E. Hilmas, William G. Fahrenholtz, David W. Lipke Jan 2024

Oxidation Of Additively Manufactured Zrb2–Sic In Air And In Co2 At 700–1000 °C, Marharyta Lakusta, Nicholas M. Timme, Abid H. Rafi, Jeremy Lee Watts, M. (Ming) C. (Chuan) Leu, Gregory E. Hilmas, William G. Fahrenholtz, David W. Lipke

Materials Science and Engineering Faculty Research & Creative Works

Oxidation behavior of additively manufactured zrb2–sic in air and in co2 is reported in the temperature range of 700–1000 °c. Observed scale morphologies in air and in co2 were similar, featuring an outer borosilicate layer and an inner porous zirconia layer containing partially oxidized silicon carbide particles and remnant borosilicate products. Oxide scale thicknesses and parabolic scaling constants in air were approximately twice those observed in co2 across all studied temperatures. Activation energies for oxidation of 140 ± 20 kj/mol in air and 110 ± 20 kj/mol in co2 were determined, indicating similar diffusion processes that appear to be rate-limiting. …


Thermal And Electrical Properties Of Single-Phase High Entropy Carbide Ceramics, Paul M. Brune, Gregory E. Hilmas, William G. Fahrenholtz, Jeremy Lee Watts, Stefano Curtarolo Jan 2024

Thermal And Electrical Properties Of Single-Phase High Entropy Carbide Ceramics, Paul M. Brune, Gregory E. Hilmas, William G. Fahrenholtz, Jeremy Lee Watts, Stefano Curtarolo

Materials Science and Engineering Faculty Research & Creative Works

Thermal and Electrical Properties Were Investigated for Five Nominally Phase-Pure High Entropy Carbide Ceramics. the Compositions (Hf0.2Nb0.2Ta0.2Ti0.2Zr0.2)C, (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C, (Hf0.2Mo0.2Ta0.2Ti0.2Zr0.2)C, (Hf0.2Ta0.2Ti0.2W0.2Zr0.2)C, and (Hf0.2Mo0.2Ti0.2W0.2Zr0.2)C Were Synthesized by Carbothermal Reduction of Oxides. the Thermal Diffusivity and Heat Capacity Were Measured from Room Temperature to 1800°C. the Room Temperature Thermal Conductivity Ranged from 5.1 W/mK for (Hf0.2Mo0.2Ti0.2W0.2Zr0.2)C to 9.0 W/mK for (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C. the Thermal Conductivity Increased over the Temperature Range with Maximum Conductivities of 19.6 W/mK Measured for (Hf0.2Mo0.2Ta0.2Ti0.2Zr0.2)C to 29.7 W/mK for (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C at 1800°C. the Electron Contribution to Thermal Conductivity Calculated from Measured Electrical Resistivity Varied from 41% to 52% of the …


High-Temperature Oxidation Behavior Of High Entropy Carbide (Tanbtiv)C In Atmospheres With Different Oxygen Contents, Ruoyu Chen, Hongbin An, Jie Zhan, Saisai Li, Aiqin Mao, Haiming Wen Jan 2024

High-Temperature Oxidation Behavior Of High Entropy Carbide (Tanbtiv)C In Atmospheres With Different Oxygen Contents, Ruoyu Chen, Hongbin An, Jie Zhan, Saisai Li, Aiqin Mao, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

A high entropy carbide (TaNbTiV)C was fabricated via spark plasma sintering of high entropy powders that were prepared using a molten salt method. The as-fabricated high entropy carbide was then investigated for its high-temperature oxidation behavior at 850 °C, under atmospheres with three different oxygen contents (20 vol%, 40 vol%, and 60 vol%). After the high-temperature oxidation process, the main phases observed in all the specimens were incompletely oxidized phase (NbxTi1-x)CyO2-y and oxides (Nb0.5Ta0.5)2O5, TiO2, and Nb2O5. Importantly, the …


Sustainable Additive Manufacturing Of Polysulfone Membranes For Liquid Separations, Brian Leonard, Harrison Loh, David Lu, Ebuka A. Ogbuoji, Isabel Escobar, Konstantinos Sierros, Oishi Sanyal Jan 2024

Sustainable Additive Manufacturing Of Polysulfone Membranes For Liquid Separations, Brian Leonard, Harrison Loh, David Lu, Ebuka A. Ogbuoji, Isabel Escobar, Konstantinos Sierros, Oishi Sanyal

UK CARES Faculty Publications

Membranes serve as important components for modern manufacturing and purification processes but are conventionally associated with excessive solvent usage. Here, for the first time, a procedure for fabricating large area polysulfone membranes is demonstrated via the combination of direct ink writing (DIW) with non-solvent induced phase inversion (NIPS). The superior control and precision of this process allows for complete utilization of the polymer dope solution during membrane fabrication, thus enabling a significant reduction in material usage. Compared to doctor blade fabrication, a 63% reduction in dope solution volume was achieved using the DIW technique for fabricating similarly sized membranes. Cross …


Graphene Reinforced Polymer Composite For Small-Scale Vertical Axis Wind Turbine Rotors, Kunal A. Bachim Jan 2024

Graphene Reinforced Polymer Composite For Small-Scale Vertical Axis Wind Turbine Rotors, Kunal A. Bachim

Mechanical and Aerospace Engineering Theses - Archive

Polymers have evolved as an indispensable asset in various sectors ranging from packaging and construction to energy and aerospace. However, the accumulation of polymer waste poses a necessity to shift toward sustainable waste management processes. Mechanical recycling is a primary method in establishing a circular economy approach for polymers. However, a fundamental challenge arises in this process: a decrease in the mechanical performance of the recycled product compared to that of its pristine counterpart.

This project addresses the challenge of enhancing the recyclability of polyethylene terephthalate (PET) from discarded polymer material by incorporating graphene nanoparticles into the polymer matrix during …


Enhancing Electromigration Reliability In Solder Interconnects Through Microstructure Control And Thermomechanical Failure Mechanisms In Thin Metal Lines Under Surge Current Conditions, Hariram Mohanram Jan 2024

Enhancing Electromigration Reliability In Solder Interconnects Through Microstructure Control And Thermomechanical Failure Mechanisms In Thin Metal Lines Under Surge Current Conditions, Hariram Mohanram

Material Science and Engineering Dissertations - Archive

The relentless miniaturization of semiconductor devices has intensified reliability challenges in electronic packaging, particularly for solder interconnects and thin metal lines. This dissertation investigates two critical failure mechanisms—electromigration (EM) and thermomechanical fatigue (TMF)—and explores strategies to mitigate these effects. Electromigration, driven by high-density current-induced atomic migration, significantly impacts solder interconnects. This study examines the role of Under-Bump Metallization (UBM) and solder microstructure in improving EM reliability. Findings reveal that thicker UBMs delay void nucleation and enhance EM resistance, while the absence of UBM leads to failure through vertical void propagation. Additionally, grain orientation, particularly the c-axis alignment in Sn grains, …


Near Infrared Upconversion Nanoparticles Modified With Semiconducting Polymers For Anti-Counterfeiting, Abraham Chibuikem Ikeji Jan 2024

Near Infrared Upconversion Nanoparticles Modified With Semiconducting Polymers For Anti-Counterfeiting, Abraham Chibuikem Ikeji

Dissertations and Theses

Lanthanide doped up-conversion nanoparticles (UCNPs) are excellent luminescent materials due to their ability to perform photon up-conversion from low energy to high energy using their triplet energy metastable states and because of their long-lived excited state. These properties enable multiple applications with the near infrared upconversion emission. They have been incorporated in developing technologies to help curb counterfeiting activities and other areas of research. However, they still have some limitations such as the hydrophobic nature of the UCNPs, and the absence of functional groups that can also help impact other desired features. Thus, in this work we have coated up-conversion …


Effect Of Admixtures On Rapid Hardening, Self-Consolidating Concrete, Haley Johnson Jan 2024

Effect Of Admixtures On Rapid Hardening, Self-Consolidating Concrete, Haley Johnson

Theses and Dissertations--Civil Engineering

Self-consolidating, rapid-hardening concrete is a sought-after product in the market now, however the effects of admixtures on fresh and hardened concrete rheology are still uncertain. This study aims to create a self-consolidating concrete (SCC) using calcium sulfoaluminate (CSA) cement for its rapid-hardening properties, and tests two set time retarders and two viscosity-modifying admixtures (VMAs) to determine how they affect the properties of concrete. The properties studied in this thesis are workability, viscosity, set times, air content, compressive strength, and freeze-thaw resistance of self-consolidating concrete. It was found that tartaric acid creates a very workable SCC with consistent results regardless of …


Processing & Properties Of Zirconium Carbide Manufactured By Ceramic On-Demand Extrusion, Clare Sabata Jan 2024

Processing & Properties Of Zirconium Carbide Manufactured By Ceramic On-Demand Extrusion, Clare Sabata

Masters Theses

"This research focuses on the development of a zirconium carbide (ZrC) paste for use in material extrusion direct ink write additive manufacturing (AM) followed by the pressure less densification of ZrC and the mechanical and thermal characterization of the resulting ceramics. A highly loaded, aqueous paste was developed using commercial ZrC powder ball milled to ~1 μm. Optimal dispersant, binder, and solids loading were found by rheological characterization. The paste composition consisted of 46-47 vol% ZrC, 43.5 vol% distilled water, 8.1 vol% dispersant, and 1.6 vol% binder. A yield stress of ~8 Pa allowed for shape retention upon removal of …