Materials Science and Engineering Commons^™

Biomimetic Oral Mucin From Polymer Micelle Networks, Sundar Prasanth Authimoolam

Theses and Dissertations--Chemical and Materials Engineering

Mucin networks are formed by the complexation of bottlebrush-like mucin glycoprotein with other small molecule glycoproteins. These glycoproteins create nanoscale strands that then arrange into a nanoporous mesh. These networks play an important role in ensuring surface hydration, lubricity and barrier protection. In order to understand the functional behavior in mucin networks, it is important to decouple their chemical and physical effects responsible for generating the fundamental property-function relationship. To achieve this goal, we propose to develop a synthetic biomimetic mucin using a layer-by-layer (LBL) deposition approach. In this work, a hierarchical 3-dimensional structures resembling natural mucin networks was generated …

Angiogenic Effect Of Bioactive Borate Glass Microfibers And Beads In The Hairless Mouse, Richard J. Watters, Roger F. Brown, D. E. Day

Biological Sciences Faculty Research & Creative Works

The purpose of this project was to investigate the angiogenic mechanism of bioactive borate glass for soft tissue repair in a 'hairless' SKH1 mouse model. Subcutaneous microvascular responses to bioactive glass microfibers (45S5, 13-93B3, and 13-93B3Cu) and bioactive glass beads (13-93, 13-93B3, and 13-93B3Cu) were assessed via: noninvasive imaging of skin microvasculature; histomorphometry of microvascular densities; and quantitative PCR measurements of mRNA expression of VEGF and FGF-2 cytokines. Live imaging via dorsal skin windows showed the formation at two weeks of a halo-like structure infused with microvessels surrounding implanted borate-based 13-93B3 and 13-93B3Cu glass beads, a response not observed with …

Safe Re-Entry Time With In-Cycle Shotcrete For Support Of Underground Excavations, Hla Aye Saw, Ernesto Villaescusa, Christopher Windsor

Shotcrete for Underground Support XII

No abstract provided.

Quality Control For Wet-Mix Fiber Reinforced Shotcrete In Ground Support, Lihe (John) Zhang, Dudley R. Morgan

Shotcrete for Underground Support XII

No abstract provided.

Engineered Fiber Reinforced Shotcrete For Efficient And Fast Ground Support Installation, N. Ginouse, S. Reny, M. Jolin

Shotcrete for Underground Support XII

No abstract provided.

Evaluation Of Wet-Mix Shotcrete Containing Set-Accelerator And Service Life Prediction, Marc Jolin, F. Melo, B. Bissonnette, P. Power, E. Demmard

Shotcrete for Underground Support XII

No abstract provided.

Finite Element Analysis Of System-Level Electronic Packages For Space Applications, Adrien Lambert, Ahsan Mian, Justin Hogan, Todd Kaiser, Brock Lameres

Mechanical and Materials Engineering Faculty Publications

Thermal analysis was required in order to aid in the design and testing of a radiation tolerant computing (RTC) system using a radiation sensor. During development of the system, different test beds were employed in order to characterize the radiation sensor and its supporting electronic systems. The most common preliminary tests are high altitude balloon tests which allow the sensor to experience cosmic radiation at high altitudes, consistent with space flight operations. In this study, finite element analysis (FEA) was used to evaluate primary system architecture, system support structures, and the flight payload in order to determine if the system …

Transport Properties Of Wet-Mix Shotcrete, Lihe (John) Zhang, Dudley R. Morgan

Shotcrete for Underground Support XII

No abstract provided.

Early-Age Behavior Of Shotcrete Using Expansive Admixture, Kyong-Ku Yun, Kassa B. Abay, Kyeo-Re Lee, Seung-Yeon Han, Kyong Namkung

Shotcrete for Underground Support XII

No abstract provided.

The Effect Of Spraying On Fiber Content And Shotcrete Properties, Marc Jolin, J.-D. Lemay, N. Ginouse, B. Bissonnette, É. Blouin-Dallaire

Shotcrete for Underground Support XII

No abstract provided.

Comparison On Different Design Approaches Applied To A New Tunnel Lining System Reinforced By Tubular Arch, C.L. Zenti, R. Perlo

Shotcrete for Underground Support XII

No abstract provided.

New Technologies In Underground Projects: Drill Core Scanning, Documentation And Analysis, Jens Wiegand

Shotcrete for Underground Support XII

No abstract provided.

Sustainable Disposal Of Coal Processing Waste Streams, Mohammad Rezaee

Theses and Dissertations--Mining Engineering

Modern coal preparation facilities incorporate a wide array of solid-solid and solid-liquid separation processes for rejecting mineral matter to meet market specifications. The coarse mineral matter is typically placed into engineered refuse piles whereas the fine refuse is either stored in impoundments or co-disposed with the coarse refuse. The discharge water from the refuse material represents an environmental concern due to the potential release of trace elements, and the subsequent elevation of total dissolved solids and conductivity. The research findings reported in this dissertation addresses sustainable coal processing waste disposal through using strategies aimed at minimizing the environmental impacts. To …

Dynamic Phases, Pinning, And Pattern Formation For Driven Dislocation Assemblies, Caizhi Zhou, Charles Reichhardt, Cynthia Olson Reichhardt, Irene J. Beyerlein

Materials Science and Engineering Faculty Research & Creative Works

We examine driven dislocation assemblies and show that they can exhibit a set of dynamical phases remarkably similar to those of driven systems with quenched disorder such as vortices in superconductors, magnetic domain walls, and charge density wave materials. These phases include pinned-jammed, fluctuating, and dynamically ordered states, and each produces distinct dislocation patterns as well as specific features in the noise fluctuations and transport properties. Our work suggests that many of the results established for systems with quenched disorder undergoing plastic depinning transitions can be applied to dislocation systems, providing a new approach for understanding pattern formation and dynamics …

Composition- And Pressure-Induced Ferroelectric To Antiferroelectric Phase Transitions In Sm-Doped Bifeo₃ System, Fei Xue, Linyun Liang, Yijia Gu, Ichiro Takeuchi, Sergei V. Kalinin, Long-Qing Chen

Materials Science and Engineering Faculty Research & Creative Works

A three-dimensional phenomenological model is proposed to describe both ferroelectricity and antiferroelectricity based on the Ginzburg-Landau-Devonshire theory. Its application to the multiferroic Sm-doped BiFeO₃ system describes the temperature-, pressure-, and composition-induced ferroelectric to antiferroelectric phase transitions. The constructed temperature-composition and temperature-pressure phase diagrams show that compressive hydrostatic pressure and Sm doping have similar effects on the ferroelectric and antiferroelectric phase transitions. It is also indicated from the temperature-pressure phase diagram that the experimentally observed phase of BiFeO₃ under the hydrostatic pressure from 3 GPa to 10 GPa is a PbZrO₃-like antiferroelectric phase.

Nanoscale Mechanical Switching Of Ferroelectric Polarization Via Flexoelectricity, Yijia Gu, Zijian Hong, Jason Britson, Long-Qing Chen

Materials Science and Engineering Faculty Research & Creative Works

Flexoelectric coefficient is a fourth-rank tensor arising from the coupling between strain gradient and electric polarization and thus exists in all crystals. It is generally ignored for macroscopic crystals due to its small magnitude. However, at the nanoscale, flexoelectric contributions may become significant and can potentially be utilized for device applications. Using the phase-field method, we study the mechanical switching of electric polarization in ferroelectric thin films by a strain gradient created via an atomic force microscope tip. Our simulation results show good agreement with existing experimental observations. We examine the competition between the piezoelectric and flexoelectric effects and provide …

Designed Synthesis Of Nanoporous Organic Polymers For Selective Gas Uptake And Catalytic Applications, Pezhman Arab

Theses and Dissertations

Design and synthesis of porous organic polymers have attracted considerable attentions during the past decade due to their wide range of applications in gas storage, gas separation, energy conversion, and catalysis. Porous organic polymers can be pre-synthetically and post-synthetically functionalized with a wide variety of functionalities for desirable applications. Along these pursuits, we introduced new synthetic strategies for preparation of porous organic polymers for selective CO₂ capture.

Porous azo-linked polymers (ALPs) were synthesized by an oxidative reaction of amine-based monomers using copper(I) as a catalyst which leads to azo-linkage formation. ALPs exhibit high surface areas of up to 1200 …

Synthesis And Fabrication Of Graphene/Conducting Polymer/Metal Oxide Nanocomposite Materials For Supercapacitor Applications, Mohamad Khawaja

USF Tampa Graduate Theses and Dissertations

The rising energy consumption worldwide is leading to significant increases in energy production with fossil fuels being the major energy source. The negative environmental impact of fossil fuel use and its finite nature requires the use of alternative sources of energy. Solar energy is a clean alternative energy source; however, its intermittent nature is a major impediment that needs to be reduced or eliminated by the development of cost effective energy storage. Thermal storage in tanks filled typically with molten salt at elevated temperatures is widely used in concentrating solar power plants to generate electricity during periods of low daytime …

Studies Related To Microbially Induced Corrosion Of Stainless Steel 304 And 316, Somil Gupta

Electronic Theses and Dissertations

Pitting corrosion of stainless steel (SS) is observed in many different industries including the dairy industry. It is of concern, because it weakens the steel, and can cause cracking. Any replacement or repair of SS equipment is very costly and also causes delays in product manufacture. Microbial Induced Corrosion (MIC) is a possible accelerator of natural corrosion seen in galvanized steel pipes. Studies have shown a correlation between surface roughness and the ability of bacteria to colonize and form biofilms. Dairy industry utilizes higher food grade SS 304 and 316. However, even these relatively corrosion resistant stainless steel grades may …

Simulation Of Infiltrating Rate Driven By Surface Tension-Viscosity Of Liquid Elements From The Titanium Group Into A Packed Bed, Arturo Medina

Open Access Theses & Dissertations

The simulation of infusion of molten reactive metals (e.g., yttrium) into a porous, carbide packed bed to create carbide and boride composites was studied at ultrahigh temperatures (>1700°C). The infusion was investigated through a computational fluid dynamic (CFD) system of capillary pores and compared to a predicted analytical calculation formulated by Selmak and Rhines. Simulations of two-phase flow penetration of yttrium into a packed bed of B4C were investigated and compared with titanium, zirconium, hafnium, and samarium liquids. The non-reactive, liquid metal infusion was primarily driven by the surface tension and viscosity. The liquid metal depth and rate of …

Hybrid Nano-Structure For Enhanced Energy Storage Devices, Mohammad Arif Ishtiaque Shuvo

Open Access Theses & Dissertations

The goal of this research is to develop electrode materials using various nano-structure hybrids for improved energy storage devices. Enhancing the performance of energy storage device has been gaining tremendous attention since it holds the key solution to advance renewable energy usage thus reduce the consumption of fossil fuels. The application of energy storage devices such as super-capacitor and Li-ion-battery has seen significant growth; however, it is still limited mainly by charge/discharge rate and energy density. One of the solutions is to use nano-structure materials, which offer higher power at high energy density and improved stability during the charge discharge …

The Influence Of Particle Content On The Equi-Biaxial Fatigue Behaviour Of Magnetorheological Elastomers, Yanfen Zhou, Stephen Jerrams, Tony Betts, Gerald Farrell, Lin Chen

Articles

The equi-biaxial fatigue behaviour of silicone based magnetorheological elastomers (MREs) with various volume fractions of carbonyl iron particles ranging between 15% and 35% was studied. Wöhler curves for each material were derived by cycling test samples to failure over a range of stress amplitudes. Changes in complex modulus (E*) and dynamic stored energy during the fatigue process were observed. As for other elastic solids, fatigue resistance of MREs with different particle contents was shown to be dependent on the stress amplitudes applied. MREs with low particle content showed the highest fatigue life at high stress amplitudes while MREs with high …

Determination Of Current Density Distribution In An Electron Beam, Yudhishthir Prasad Kandel

Legacy Theses & Dissertations (2009 - 2024)

Electron beams are useful in many applications because they can be focused down to a spot far exceeding the physical limit of focusing visible light or x-rays. Additionally, electron beams are useful in transferring concentrated amounts of energy to a very small well defined region of a target for a fixed duration. This has led to the development of both scanning electron microscopes (SEMs) and electron beam lithography. The goal of this work was to develop a general method that accurately and easily yields the best estimate of the electron current density distribution of a focused electron beam, known as …

Study Of Millisecond Laser Annealing On Ion Implanted Soi And Application To Scaled Finfet Technology, Tyler J. Michalak

Legacy Theses & Dissertations (2009 - 2024)

The fabrication of metal-oxide-semiconductor field effect transistors (MOSFET) requires the engineering of low resistance, low leakage, and extremely precise p-n junctions. The introduction of finFET technology has introduced new challenges for traditional ion implantation and annealing techniques in junction design as the fin widths continue to decrease for improved short channel control. This work investigates the use of millisecond scanning laser annealing in the formation of n-type source/drain junctions in next generation MOSFET.

Optical Metrology For Directed Self-Assembly Patterning Using Mueller Matrix Spectroscopic Ellipsometry Based Scatterometry, Dhairya J. Dixit

Legacy Theses & Dissertations (2009 - 2024)

The semiconductor industry continues to drive patterning solutions that enable devices with higher memory storage capacity, faster computing performance, lower cost per transistors, and higher transistor density. These developments in the field of semiconductor manufacturing along with the overall minimization of the size of transistors require cutting-edge metrology tools for characterization.

Implementation Of Strategies To Improve The Reliability Of Iii-Nitride Photodetectors Towards The Realization Of Visible And Solar-Blind Imaging Arrays, John Bulmer

Legacy Theses & Dissertations (2009 - 2024)

Ultraviolet (UV) radiation detectors are being heavily researched for applications in non-line-of-sight (NLOS) communication systems, flame monitoring, biological detection, and astronomical studies. These applications are currently being met by the use of Si-based photomultiplier tubes (PMTs), which are bulky, fragile, expensive and require the use of external filters to achieve true visible-blind and solar-blind operation.

Initiated Chemical Vapor Deposition (Icvd) Polymer Thin Films : Structure-Property Effects On Thermal Degradation And Adhesion, Vijay Jain Bharamaiah Jeevendrakumar

Legacy Theses & Dissertations (2009 - 2024)

Opportunities and challenges for chemical vapor deposition (CVD) of polymer thin films stems from their applications in electronics, sensors, and adhesives with demands for control over film composition, conformity and stability. Initiated chemical vapor deposition (iCVD) is a subset of the CVD technique that conjoins bulk free-radical polymerization chemistry with gas-phase processing. The novelty of iCVD technique stems from the use of an initiator that can be activated at low energies (150 – 300 °C) to react with surface adsorbed monomer to form a polymer film. This reduces risk for potential unwarranted side-reactions.

Ion Implantation In Zno : Defect Interaction And Impurity Diffusion, Faisal Yaqoob

Legacy Theses & Dissertations (2009 - 2024)

In the first part of this research we studied the entropy changes in diffusion prefactor and its

High Frequency Signal Transmission In Through Silicon Via Based 3d Integrated Circuit, Min Xu

Legacy Theses & Dissertations (2009 - 2024)

Through silicon vias (TSVs) enable 3-dimensional (3D) integrated circuits (ICs), which have the potential to reduce the power consumption, interconnect length and overall communication latency in modern nanoelectronics systems. High-speed signal transmission channels through stacked silicon substrates are critical for 3D heterogeneous integration. This work presents systematic analyses of fabricated 3D IC test structures. This includes test structure design, fabrication, experimental characterization, equivalent circuit modeling and full wave simulations for high-speed signal transmission of the TSV based 3D IC channels.

The Impact Of Seed Layer Structure On The Recrystallization Of Ecd Cu And Its Alloys, Brendan B. O'Brien

Legacy Theses & Dissertations (2009 - 2024)

Despite the significant improvements originally offered by the use of Cu over Al as the interconnect material for semiconductor devices, the continued down-scaling of interconnects has presented significant challenges for semiconductor engineers. As the metal line widths shrink, both the conductivity and reliability of lines decrease due to a stubbornly fine-grained microstructure in narrow lines.