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2025

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Immersive Extended Reality For Lower Limb Rehabilitation: Design, Deployment, And Pilot Study, Jeremy Varghese Jan 2025

Immersive Extended Reality For Lower Limb Rehabilitation: Design, Deployment, And Pilot Study, Jeremy Varghese

Electronic Theses & Dissertations (2024 - present)

This thesis presents the design, deployment, and pilot study of an immersive extended-reality (XR) rehabilitation system integrated with a ceiling-mounted dynamic body-weight support device (Vector Gait and Safety System), aimed at improving lower-limb rehabilitation out- comes. The implemented system combined immersive virtual tasks—such as Touch Wall, Ball Launcher, Obstacle Dodge, and Stepping Stones—with real-time movement tracking, enabling detailed kinematic analysis and personalized therapy. A pilot study conducted at Sunnyview Rehabilitation Hospital involved seven patients with various mobility impairments, providing quantitative performance metrics and quali- tative user feedback. Results demonstrated consistent patient engagement, measurable im- provements in gait speed and task …


The Excessive Cost Of Health: An Analysis Of Pharmaceutical Accessibility Issues In The United States, Henry Woodman Curtis Jan 2025

The Excessive Cost Of Health: An Analysis Of Pharmaceutical Accessibility Issues In The United States, Henry Woodman Curtis

Electronic Theses & Dissertations (2024 - present)

Compared to the rest of the world, the United States has one of the worst-performing health care systems. While this is influenced by our hospital systems and clinical care in certain contexts, one of the biggest culprits for our poor ratings is the cost and availability of prescription medications. We pay more than any comparable country for the exact same medications and have a harder time actually accessing them. In this dissertation, I aim to analyze how individuals, companies, and governmental agencies have responded to various instances of high-cost or low-availability prescription medications. To begin, I examine pharmaceutical patenting practices …


Three Essays On Addressing Conflicts And Consensus During Energy Transitions, Paul Inseok Jo Jan 2025

Three Essays On Addressing Conflicts And Consensus During Energy Transitions, Paul Inseok Jo

Electronic Theses & Dissertations (2024 - present)

Addressing the current climate crisis becomes more urgent, but also controversial. This is because the move toward a renewable energy system tends to produce new winners and losers by generating disproportionate outcomes across different stakeholders. Given this context, more actors and organizations are engaged in the policymaking process of energy transitions while competing or cooperating to defend their interests and values. Therefore, it is pivotal to understand these dynamic interactions to achieve a just transition based upon energy justice. This research thus strives to respond to this research question: How can different coalitions and stakeholders reach consensus by mitigating tensions …


Dynamics Of Mesoscale Offshore Wind Flows From An Observational And Modeling Perspective: Implications For Offshore Wind Energy, Elizabeth J. Mccabe Jan 2025

Dynamics Of Mesoscale Offshore Wind Flows From An Observational And Modeling Perspective: Implications For Offshore Wind Energy, Elizabeth J. Mccabe

Electronic Theses & Dissertations (2024 - present)

Mid-latitude coastal regions of the United States, such as the New York Bight (NYB), are playing a major role in the development of offshore wind energy. However, mesoscale dynamics of local and regional circulations in these offshore waters are poorly understood. The sea breeze, especially in the NYB, will play a key role in the development of offshore wind energy, given the favorable wind speeds and high capacity factors during periods of peak demand. With limited vertical wind profile observations available offshore, the ability to accurately forecast and understand the spatiotemporal extent of the sea breeze and often associated low-level …


Complex Missing Data Problems In Education Surveys, Thomas Wesley Robertson Jan 2025

Complex Missing Data Problems In Education Surveys, Thomas Wesley Robertson

Electronic Theses & Dissertations (2024 - present)

Missing data are a nearly universal problem in human subjects research, including in education. However, reporting and addressing missing data is an issue, despite guidelines from the APA style guide and the What Works Clearinghouse, as well as guidance from prominent statisticians on the best methods to use. Prior research conducted in 2004 and 2014 found that in the field of education, most studies do not report or address missing data. In addition, no study has looked specifically at how missing data are reported and addressed in complex surveys. The current study has two main objectives: first, to determine if …


Secured Communication And Coexistence For Efficient Spectrum Utilization, Xue Wei Jan 2025

Secured Communication And Coexistence For Efficient Spectrum Utilization, Xue Wei

Electronic Theses & Dissertations (2024 - present)

Over the years, the demand for wireless communications has grown exponentially, resulting in a scarcity of available spectrum. This scarcity leads to the need for efficient spectrum utilization, a key factor in ensuring reliable and uninterrupted communications. One of the key challenges in achieving reliable communication is ensuring secure transmissions to protect the privacy and integrity of data for active users. Wireless communications are vulnerable to eavesdropping, interception, and unauthorized access, which can compromise the confidentiality and integrity of transmitted data. The coexistence of multiple wireless communication systems is another challenge to be addressed for passiver users. In many cases, …


Food Rescue, Food Waste, And Policy In New York: A Mixed-Methods Study Of Food System Impacts, Mariana Torres Arroyo Jan 2025

Food Rescue, Food Waste, And Policy In New York: A Mixed-Methods Study Of Food System Impacts, Mariana Torres Arroyo

Electronic Theses & Dissertations (2024 - present)

This dissertation investigates how food donation policies in New York State influence the recovery, redistribution, and waste of surplus fresh produce, with a focus on fruits and vegetables. Using an interdisciplinary, systems-based approach that integrates system dynamics modeling with qualitative, community-engaged research, the study analyzes the effectiveness and unintended consequences of three major policies: Nourish New York, the Farm to Food Bank tax credit, and the Food Donation and Food Scraps Recycling Law.

Chapter 2 uses simulation modeling to examine how the tax credit and waste ban affect produce recovery and redistribution. Results show that while both policies can boost …


Safeguard Cyberspace In Ransomware Era: Risk Analysis & Cyber Insurance, Li Huang Jan 2025

Safeguard Cyberspace In Ransomware Era: Risk Analysis & Cyber Insurance, Li Huang

Electronic Theses & Dissertations (2024 - present)

The increasing frequency and severity of ransomware attacks pose significant challenges for organizational cybersecurity. Fragmentation across disciplines in cyber defense has created practical gaps in the development of the necessary capabilities needed to address rapidly evolving cyber threats. This study explores the impact of ransomware attacks and the evolving role of cyber insurance as a proactive cybersecurity partner. Bridging the gap between actuarial science and cyber risk management, it proposes an interdisciplinary framework that quantifies the impact of ransomware and integrates cyber insurance into cybersecurity strategies.

The primary contribution of this study is methodology. We present a framework that remains …


Comparison Of Methane Emission Quantification Methods At Landfills In New York State, Alexandra M. Catena Jan 2025

Comparison Of Methane Emission Quantification Methods At Landfills In New York State, Alexandra M. Catena

Electronic Theses & Dissertations (2024 - present)

Greenhouse gas (GHG) emission increases are a consequence of global population rise and economic growth. It is well known that carbon dioxide is the dominant GHG by mass, but methane has received increasing attention recently due to its high warming potential and relatively short lifetime of about a decade. Methane has several different types of both natural and anthropogenic sources including wetlands, waste management, energy, agriculture and farming, and wildfires, which makes tracking and reducing methane emissions a complex problem. The emission rates of each of these sources are highly uncertain due to differing emission estimation methods, which can be …


Street Outreach And Reentry: The Role Of Community Violence Intervention In The Reintegration Of Returning Citizens, Hilary Jackl Jan 2025

Street Outreach And Reentry: The Role Of Community Violence Intervention In The Reintegration Of Returning Citizens, Hilary Jackl

Electronic Theses & Dissertations (2024 - present)

Amidst ongoing efforts to reduce the nation’s prison population, as well as calls to defund the police and invest in civilianized public safety strategies following the murder of George Floyd, community-based violence intervention (CVI) strategies have been increasingly recognized as a critical means by which to ameliorate the United States’ enduring gun violence problem without exacerbating the harms of overpolicing and mass incarceration. However, most contemporary CVI research has assessed program impacts on neighborhood rates of gun violence and has produced conflicting findings, leading scholars to call for the need to examine a wider range of program-related functions and outcomes. …


Development Of Group Iii-V Quantum Confinement-Enabled Detectors: Bias-Tunable Quantum Well Infrared Photodetector (Qwip) And Quantum Dot Scintillation Detector (Qdsd), Gyana R. Biswal Jan 2025

Development Of Group Iii-V Quantum Confinement-Enabled Detectors: Bias-Tunable Quantum Well Infrared Photodetector (Qwip) And Quantum Dot Scintillation Detector (Qdsd), Gyana R. Biswal

Electronic Theses & Dissertations (2024 - present)

This dissertation discloses the physics, fabrication, characterization, and analysis of two novel types of group III-V semiconductor detectors relying on quantum confinement of carriers, namely voltage-tunable quantum well infrared photodetectors (QWIP) and a high-yield ultrafast quantum dot scintillation detector (QDSD). Both QWIP and QDSD heterostructures presented here were grown on 3” GaAs (001) substrates using molecular beam epitaxy (MBE).

A major part of the dissertation focuses on development of the voltage-tunable QWIPs targeting detection in the mid-wave infrared region (MWIR) (3μm -5μm) and long-wave infrared region (LWIR) (8μm -12μm) with control of sensitivity by the applied bias. The QWIPs utilize …


Essays On Technological Change And Scientific Research, Max Mayca Jan 2025

Essays On Technological Change And Scientific Research, Max Mayca

Electronic Theses & Dissertations (2024 - present)

The primary objective of economic science has long been to understand and promote growth, as it contributes to a more prosperous civilization and improves individual well-being. The core drivers of growth—capital accumulation, human capital development, and technological progress—are well-established. While capital deepening enables scaling of production, and human capital enhances labor productivity, technological and scientific advancements remain the most critical, as they continually redefine the efficiency frontier. Given this centrality, it is essential to understand how technological progress affects labor markets, how research resources should be allocated, and how technology relates to human capital formation.

The first part of this …


Nola 2150, Kristopher Ferber Jan 2025

Nola 2150, Kristopher Ferber

Electronic Theses & Dissertations (2024 - present)

Abstract

Speculative fiction often takes a dystopic approach where authors envision what will be lost from books being banned in Fahrenheit 451 to us losing our civil liberties in 1984 to most of humanity being wiped out by an engineered virus in Oryx and Crake. This creative thesis takes a more optimistic approach by the act of preservation. In this case the city of New Orleans thriving as an underwater city protected by a glass dome in the year 2150. The city’s vibrant culture remains the same despite being almost too close to comfort to marine life. This work …


Interfacing Neural Models: Biocompatibility And Fabrication Of A Flexible, Self-Folding Microelectrode Array, Fernando A. Pesantez Torres Jan 2025

Interfacing Neural Models: Biocompatibility And Fabrication Of A Flexible, Self-Folding Microelectrode Array, Fernando A. Pesantez Torres

Electronic Theses & Dissertations (2024 - present)

Neurodegenerative diseases pose a formidable challenge in modern medicine, necessitating the development of advanced research tools that can elucidate their complex pathophysiology. Recent advancements in neurodegenerative disease research have led to the development of three-dimensional (3D) neurodegenerative organoids using human induced pluripotent stem cells (hiPSCs). These organoids closely mimic human brain architecture and functionality, providing a valuable tool for understanding complex diseases. Additionally, the ability to generate and study brain organoids consistently and in large quantities holds potential for a controlled in vitro setting and high-throughput drug screening. However, these models are complex systems requiring specialized maintenance, analysis, and manipulation …


Improving Generalizability In Image Manipulation Detection, Zhenfei Zhang Jan 2025

Improving Generalizability In Image Manipulation Detection, Zhenfei Zhang

Electronic Theses & Dissertations (2024 - present)

Image manipulation detection (IMD) aims to determine whether an image has been tampered with and to identify the manipulated regions. These capabilities have become increasingly important with the rapid advancement of media editing and generation technologies, such as Photoshop and generative AI methods, which underscore the need for robust tools for media authentication. Although current state-of-the-art (SoTA) methods achieve strong results on common manipulation types, such as splicing, copy-move, and removal, they often struggle to generalize to manipulation types not represented in the training data. Consequently, their real-world applicability remains limited, with performance degrading significantly in practical scenarios.

In this …


Buoy-Based Eddy Covariance Drag Coefficient At A Near-Shore And Offshore Site, David P. Marcial Jan 2025

Buoy-Based Eddy Covariance Drag Coefficient At A Near-Shore And Offshore Site, David P. Marcial

Electronic Theses & Dissertations (2024 - present)

An eddy covariance (EC) flux system was integrated onto a Navy Oceanographic Meteorological Automatic Device (NOMAD) floating lidar buoy fitted for measuring the offshore wind resource. The EC flux system consisted of two sonic anemometers and an inertial measurement unit that together provided high-frequency (10 Hz) motion-corrected wind measurements. To assess possible impacts of flow distortion, EC momentum fluxes (10 min) were calculated in gravity-aligned, natural, and planar fit (PF) coordinate frames. The buoy was anchored near the Martha’s Vineyard Coastal Observatory Air-Sea Interaction Tower (ASIT; near-shore) for validation of the buoy-based EC fluxes against the fixed tower measurements before …


Advancing 4h-Silicon Carbide Power Mosfets Through Three-Dimensional Technology Computer Aided Design Optimization, Skylar A. Deboer Jan 2025

Advancing 4h-Silicon Carbide Power Mosfets Through Three-Dimensional Technology Computer Aided Design Optimization, Skylar A. Deboer

Electronic Theses & Dissertations (2024 - present)

This research contributes to the advancement of 1.2 kV 4H-Silicon Carbide (SiC) Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) through the development and implementation of sophisticated three-dimensional Technology Computer-Aided Design (3D TCAD) methodologies. These advanced simulation techniques enable comprehensive evaluation of innovative unit cell architectures that remain inaccessible to conventional two-dimensional (2D) TCAD approaches. By leveraging these 3D simulation capabilities, this work facilitates significant improvements in both the performance and reliability of next-generation wide-bandgap power devices.

Power devices convert electrical energy between different forms throughout the power grid making them essential in applications ranging from personal electronics, electric vehicles, renewable energy systems, industrial …


Effects Of Formative Assessment On Students’ Regulation Of Learning: A Meta-Analysis, Ching-Yen Yu Jan 2025

Effects Of Formative Assessment On Students’ Regulation Of Learning: A Meta-Analysis, Ching-Yen Yu

Electronic Theses & Dissertations (2024 - present)

Does formative assessment (FA) promote self-regulated learning (SRL)? Theoretically, FA has long been believed to facilitate SRL due to their overlapping conceptual frameworks, yet empirical evidence has remained scattered and inconclusive. This study presents the first comprehensive, large-scale meta-analysis to examine whether, to what extent, for whom, and under what conditions FA enhances SRL.

Following a preregistered, PRISMA-guided protocol, we systematically searched the literature from 1998 to 2024 and synthesized 999 effect sizes from 138 studies (n = 23,293 students) using multilevel meta-analytic models that accounted for dependent effects. Across educational levels and contexts, FA, on average, demonstrated a …


Sulfur Chemistry For Protein Synthesis And Modification: From Thiolactone To Bicyclic Sulfoxide Frameworks, Yuming Wen Jan 2025

Sulfur Chemistry For Protein Synthesis And Modification: From Thiolactone To Bicyclic Sulfoxide Frameworks, Yuming Wen

Electronic Theses & Dissertations (2024 - present)

This dissertation explores two intersecting themes in modern chemical biology: (1) the design of novel ligands for transition-metal catalysis, and (2) the development of thiolactone-mediated strategies for protein synthesis and modification in aqueous media. Together, these studies advance chemical methods for precise molecular transformations under mild, biocompatible conditions.

In the first chapter, a geometrically constrained bicyclic [3.3.1] sulfoxide framework was developed as a new class of bissulfoxide ligands for palladium-catalyzed C–H functionalization. The ligand was synthesized concisely from thiophenol through a three-step sequence and shown to promote allylic C–H amination and alkylation reactions with high efficiency. The catalytic system tolerated …


Teacher Retention Bright Spots: A Four Case Analysis, John Costello Jan 2025

Teacher Retention Bright Spots: A Four Case Analysis, John Costello

Electronic Theses & Dissertations (2024 - present)

The teacher retention crisis has been extensively studied over the 21st century. Robust survey data from the National Center of Educational Statistics (NCES) has produced volumes on the quantitative characteristics of the teachers, students, and schools associated with low teacher retention (Ingersoll, 2001; Boyd et al., 2011; Ronfeldt, Loeb & Wyckoff, 2013). However, few studies have examined what is going right at high poverty schools which nonetheless maintain exceptionally high teacher retention. This dissertation utilizes a positive deviance lens to examine four schools; two typical schools that had normal teacher retention rates for New York State, and two outlier schools …


Investigation Of New Superconducting Materials For The Next Generation High-Performance Rf Superconducting Cavities For Particle Accelerators, Alex Gurevich, Jean Delayen, Chang-Beom Eom, Gianluigi Ciovati Jan 2025

Investigation Of New Superconducting Materials For The Next Generation High-Performance Rf Superconducting Cavities For Particle Accelerators, Alex Gurevich, Jean Delayen, Chang-Beom Eom, Gianluigi Ciovati

Physics Faculty Publications

In this DOE-funded project DE-SC0010081-020 Old Dominion University (ODU) in collaboration with University of Wisconsin (UW) and Jefferson Laboratory have investigated both experimentally and theoretically electromagnetic response and losses in multilayered superconducting structures made of new SRF materials which can push the field and Q performance limits of accelerating cavities.


Design Of A 915 Mhz Conduction-Cooled Cryomodule, G. Ciovati, J. Armstrong, A. Castilla, G. Cheng, J. Colley, K. Harding, G. Hayes, J. Vennekate, J. Lewis, J. Rathke, T. Schultheiss Jan 2025

Design Of A 915 Mhz Conduction-Cooled Cryomodule, G. Ciovati, J. Armstrong, A. Castilla, G. Cheng, J. Colley, K. Harding, G. Hayes, J. Vennekate, J. Lewis, J. Rathke, T. Schultheiss

Physics Faculty Publications

High-power, compact, continuous-wave (CW) linear electron accelerators with beam energies of up to 10 MeV are being considered for possible industrial applications. Conduction-cooled, superconducting radio-frequency (SRF) technology allows operating such machines at high electrical efficiency, thereby reducing the operating cost significantly. A prototype conduction-cooled SRF cryomodule has been designed and components are currently being manufactured. The cryomodule features a two-cell, 915 MHz SRF cavity, two cryocoolers, a fundamental power coupler, two magnetic shields, a thermal shield and warm-to-cold transitions. The cryomodule has been designed to be able to provide an energy gain of 3.5 MeV to a CW electron beam …


Unveiling The Interplay: Cold Work, Recrystallization, And Flux Expulsion, P. Dhakal, B. D. Khanal, S. Balachandran, S. Chetri, P. J. Lee, G. Ciovati Jan 2025

Unveiling The Interplay: Cold Work, Recrystallization, And Flux Expulsion, P. Dhakal, B. D. Khanal, S. Balachandran, S. Chetri, P. J. Lee, G. Ciovati

Physics Faculty Publications

The fabrication of SRF cavities from sheet materials includes deep-drawing, electron beam welding, chemical and mechanical polishing, high-temperature heat treatment, and material diffusion. The performance of these cavities is frequently constrained by magnetic flux trapping. In this presentation, we thoroughly examine how recrystallization influences flux expulsion in SRF cavities, using cold-worked niobium sheets from various suppliers. Our findings reveal that cold-worked sheets enhance flux expulsion, especially at lower heat treatment temperatures, by promoting improved recrystallization. In particular, a traditionally fabricated Nb cavity half-cell from an annealed poly-crystalline Nb sheet after an 800 C heat treatment leads to a bi-modal microstructure …


Viscoelastic Materials Evaluated For Blast-Resistant Designs, M. Sutter, C. Thomas, A. D. Douglas, F. Dogan, C. E. Johnson Jan 2025

Viscoelastic Materials Evaluated For Blast-Resistant Designs, M. Sutter, C. Thomas, A. D. Douglas, F. Dogan, C. E. Johnson

Mining Engineering Faculty Research & Creative Works

Viscoelastic materials have extensive military applications due to their energy absorption capabilities, with the potential to reduce blast energy imposed on buildings, vehicles, and personnel. Based on current literature, limited information is available regarding the mitigation of blast energy related to these uses. The impact of thickness, nanoparticle addition, and layering variation was assessed in this study using commercially available viscoelastic materials in open-air blasts of Composition C4 to determine shock energy mitigation capabilities. Time-pressure waveforms were recorded to identify optimal changes in shock wave characteristics: reduced peak pressure, positive phase duration, and impulse, with increased rise times. Results were …


Optimizing Hy Wet Ball Mill Efficiency Using Response Surface Methodology, Peng Chen, Ying Hou, Hongxu Lv, Ahmed Sobhy Jan 2025

Optimizing Hy Wet Ball Mill Efficiency Using Response Surface Methodology, Peng Chen, Ying Hou, Hongxu Lv, Ahmed Sobhy

Mining Engineering Faculty Research & Creative Works

This study uses response surface methodology (RSM) with a central composite design to optimize the HY wet ball mill work index. Key operational parameters—ore quantity, water addition, and media proportion—were systematically investigated. Variance analysis identified these factors as statistically significant (p < 0.0001), with ore quantity exhibiting the strongest influence (F value = 82.67). Optimal conditions (water addition: 1083.880 mL, media filling rate: 40.362%, ore quantity: 1827.130 g) achieved a minimum work index of 10.195 kW h t−1. Validation tests confirmed the model's accuracy, yielding an average work index of 10.168 kW h t−1 (deviation: 0.027 kW h t−1). Compared to single-factor tests, RSM optimization reduced energy consumption by 3.76% (0.3975 kW h t−1), translating to annual savings of $214,000 for a mid-sized processing plant. This demonstrates RSM's efficacy in …


Using Telemetry To Assess Operator Effects On Hydraulic Shovel Energy Efficiency. Part Ii: Assessing Operator Effects, Noah Adekunle Aluko, Kwame Awuah-Offei Jan 2025

Using Telemetry To Assess Operator Effects On Hydraulic Shovel Energy Efficiency. Part Ii: Assessing Operator Effects, Noah Adekunle Aluko, Kwame Awuah-Offei

Mining Engineering Faculty Research & Creative Works

In this second part of a two-part series, this study investigates whether operator practices significantly affect the energy efficiency of hydraulic shovels, using detailed telemetry data. Rather than assuming this relationship, the research systematically tests it through a combination of statistical and regression analyses. First, Welch's and Kruskal–Wallis ANOVA confirm that operators differ significantly in their energy efficiency (p = 0.0000). Next, correlation analysis links parameters identified in Part I to energy per unit loading rate, and difference regression analysis determines which parameters most strongly influence efficiency variations. The results show that differences in payloads are the primary driver of …


Developing An Annual Review Of The Literature, Weinstein R Amy, Szauter Karen, Duca Nicholas, Jacob Jackcy, Ismail Nadia, Pincavage Amber, Walsh Katherine, Alexandraki Irene Jan 2025

Developing An Annual Review Of The Literature, Weinstein R Amy, Szauter Karen, Duca Nicholas, Jacob Jackcy, Ismail Nadia, Pincavage Amber, Walsh Katherine, Alexandraki Irene

Faculty, Staff and Students Publications

Many national meetings and speaker series feature an "Annual Review of the Literature" (ARL) session in which an individual or team presents a sampling of articles, selected and prepared because they represent important current topics or new ideas in the discipline of interest. Despite this, there is little in the medical literature describing how to thoughtfully and systematically develop these sessions. We identify best practices that we have developed and used in the United States Clerkship Directors of Internal Medicine (CDIM) over many years. These include identification of a theme, team assembly, timeline development, search strategy and rubric development and …


Navigation In Underground Mine Environments: A Simulation Framework For Quadruped Robots, Yixiang Gao, Kwame Awuah-Offei Jan 2025

Navigation In Underground Mine Environments: A Simulation Framework For Quadruped Robots, Yixiang Gao, Kwame Awuah-Offei

Mining Engineering Faculty Research & Creative Works

Quadruped robots have shown significant potential for navigating complex and hazardous environments, such as underground mines, where traditional wheeled or tracked systems have limitations. However, their development and deployment are hindered by the disparity between controlled laboratory testing and real-world conditions and the lack of tools (e.g., simulation testbeds) that expedite the required development and testing. This work develops a simulation testbed for expediting and advancing navigation algorithms, perception systems, and control strategies for quadruped robots in subterranean and hazardous environments. By utilizing high-fidelity 3D maps, ranging from intricate cave systems to real-world sites like the Edgar Mine, simulation environment …


Optimizing Acid Mist Suppression: Unraveling Surfactant Effects On Bubble Formation And Bursting Dynamics In Copper Electrowinning, Ashish Kakoria, Mirza Muhammad Zaid, Aamir Iqbal, Ellen Amoako Afful, Guang Xu Jan 2025

Optimizing Acid Mist Suppression: Unraveling Surfactant Effects On Bubble Formation And Bursting Dynamics In Copper Electrowinning, Ashish Kakoria, Mirza Muhammad Zaid, Aamir Iqbal, Ellen Amoako Afful, Guang Xu

Mining Engineering Faculty Research & Creative Works

The working mechanism of surfactant to reduce acid mist in copper electrowinning system is not well understood. Most of the studies are based on the surface tension reduction phenomenon but this is not the only function that causes acid mist reduction. In this paper, we investigated the effect of different surfactants on a bubble's residence time, terminal velocity, flow regime, and bursting dynamics using a high-speed camera. We have evaluated five different surfactants and found that the presence of surfactants reduces the terminal velocity, bubble diameter, and increases the residence time of the bubble in electrolyte. Especially for FC-1100, the …


Cracking The Code: Harnessing Serpentinization-Driven Micro-Crack Networks For Hydrogen Generation And Subsurface Resource Recovery, U. Mutlu, G. Boitnott, A. Lisjak, J. Ha, O. Mahabadi, P. Connolly, B. N. Tunnell, T. Sherizadeh, S. Nowak, J. E. Olson Jan 2025

Cracking The Code: Harnessing Serpentinization-Driven Micro-Crack Networks For Hydrogen Generation And Subsurface Resource Recovery, U. Mutlu, G. Boitnott, A. Lisjak, J. Ha, O. Mahabadi, P. Connolly, B. N. Tunnell, T. Sherizadeh, S. Nowak, J. E. Olson

Mining Engineering Faculty Research & Creative Works

This study focuses on simulating volume-increasing processes caused by natural hydrogen-generating serpentinization, a reaction in which olivine and pyroxene typically transform into serpentine minerals. The volume increase leads to crack propagation along grain interfaces and new crack generation within unreacted crystals (aka grains). The interplay between thermo-hydro-mechanicalchemical (THMC) conditions plays a critical role in the initiation, propagation, and coalescence of various fracture surfaces, which enhances permeability and can accelerate serpentinization and hydrogen production rates. In the scenarios considered, chemical reactions between formation brine and reactive minerals result in volumetric expansion, generating stress and promoting the propagation of micro-cracks. Our results …