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Evaluating And Managing Ccr Variability At An Active Beneficial Use Clean Closure Site, John Garten, Bob Baker, Lee Lenhart May 2026

Evaluating And Managing Ccr Variability At An Active Beneficial Use Clean Closure Site, John Garten, Bob Baker, Lee Lenhart

World of Coal Ash Proceedings

The basin is a 132-acre (534,200 square meter) coal combustion residual (CCR) disposal impoundment that has been undergoing closure-by-removal since 2021, with CCRs harvested for use in concrete manufacturing. Excavated CCRs are processed on-site through initial drying and screening before being routed through a thermal beneficiation process. Despite an extensive pre-closure CCR characterization program, pockets of material encountered in 2025 caused significant off-specification issues for the beneficiation feedstock that required immediate corrective action. To address this, a supplemental surveying, sampling, and on-site testing program was implemented to obtain additional grainsize and Loss on Ignition (LOI) data for active and upcoming …


Identifying And Controlling Landfill Construction Impacts To Stormwater Flow Paths, Kory Anstead May 2026

Identifying And Controlling Landfill Construction Impacts To Stormwater Flow Paths, Kory Anstead

World of Coal Ash Proceedings

This presentation will examine the engineering challenges and lessons learned associated with construction impacts and altered stormwater flow paths in the vicinity of a Sediment Pond adjacent to a newly constructed landfill. During construction activities, the sediment basin liner experienced multiple instances of flotation. Early corrective measures were implemented as quick fixes; however, these proved ineffective and ultimately necessitated more comprehensive solutions once the underlying causes were better understood. The presentation will begin with an analysis of the initial liner flotation events, focusing on the conditions that led to the problem, the immediate responses, and the eventual engineered solution. It …


Three Use Cases For Interferometric Synthetic Aperture Radar (Insar) For Coal Ash Combustion (Ccr) Pond Closure Projects, Zach Boucias May 2026

Three Use Cases For Interferometric Synthetic Aperture Radar (Insar) For Coal Ash Combustion (Ccr) Pond Closure Projects, Zach Boucias

World of Coal Ash Proceedings

Interferometric Synthetic Aperture Radar (InSAR) is a satellite-based radar system that uses electromagnetic pulses and advanced post-processing software to detect ground subsidence across large areas with millimetric precision. This paper has two primary objectives: (1) to outline the advantages and limitations of InSAR and (2) to present three specific use cases for InSAR in connection with coal combustion residual (CCR) pond closures. InSAR offers key advantages over traditional monitoring methods: remote monitoring without field intervention, full-surface coverage, all-weather and day/night operation, and high precision. InSAR also has limitations in connection with rapidly changing surface conditions, and the presence of water …


Harvesting Rare Earths From Coal Ash Using An Ionic Liquid, Laura Stoy May 2026

Harvesting Rare Earths From Coal Ash Using An Ionic Liquid, Laura Stoy

World of Coal Ash Proceedings

This presentation highlights a promising early-stage pathway for transforming coal fly ash from a long-term liability into a source of both critical minerals and construction materials. The speaker describes a recyclable ionic-liquid process that, at bench scale, demonstrates selective recovery of rare earth elements (REEs) from a wide range of U.S. fly ashes under mild conditions while preserving the treated solids for potential use as supplementary cementitious materials (SCMs). Attendees gain insight into why this chemistry is attracting attention: it avoids full acid digestion, shows strong preference for REEs over bulk metals, and enables repeated solvent reuse in a closed …


Testing Of Accelerated Pozzolanic Activity Of Fly Ash, Anne Oberlink, Tom Robl, Bob Jewell, Haley Johnson May 2026

Testing Of Accelerated Pozzolanic Activity Of Fly Ash, Anne Oberlink, Tom Robl, Bob Jewell, Haley Johnson

World of Coal Ash Proceedings

The determination of the pozzolanic reaction in fly ash by ASTM strength activity index has been shown to be problematic, frequently producing false positives. The use of Wenner probe resistivity has been demonstrated to be rapid, simple and non-destructive method, producing no false positives. However, using this method and confirming it with other techniques finds that the reaction itself is slow with a dilatancy of 28 days or more before the measurements become discriminatory, a major drawback to this method. This study used high-temperature, high humidity curing of OPC-based mortars with various fly ash sources to determine how pozzolanic activity …


Innovative Analysis Of Groundwater Data For Scalable, Defensible, And Predictive Compliance, Shannon Zahuranec May 2026

Innovative Analysis Of Groundwater Data For Scalable, Defensible, And Predictive Compliance, Shannon Zahuranec

World of Coal Ash Proceedings

Groundwater monitoring networks at coal combustion residual (CCR) facilities now yield dataset volumes that routinely exceed the capacity of traditional, univariate interpretation. This presentation introduces a scalable multivariate and machine learning (ML) framework that prioritizes understanding data structure before predictive models are applied. The workflow applies Principal Component Analysis and other multivariate statistics to groundwater datasets, to illustrate how unsupervised learning can rapidly reveal dominant sources and controls on impacted and unimpacted groundwater quality. The talk frames multivariate analysis as a practical portfolio management tool, emphasizing inference categories rather than concentrations or site identifiers. Fleet-scale multivariate screening offers strategic advantages …


Subsurface Delineation Of Coal Combustion Residuals Using Multiple Geophysical Methods, Eric Hageman, Adam Rak, Thomas Jordan, Kate Mckinley May 2026

Subsurface Delineation Of Coal Combustion Residuals Using Multiple Geophysical Methods, Eric Hageman, Adam Rak, Thomas Jordan, Kate Mckinley

World of Coal Ash Proceedings

Geophysical techniques provide alternative methods of Coal Combustion Residual (CCR) delineation and characterization to supplement more invasive boring programs used for beneficial reuse planning. A demonstration project was designed to characterize the electromagnetic and seismic stratigraphy of CCR material and test the effectiveness of three geophysical techniques: Electrical Resistivity Imaging (ERI), Transient Electromagnetic (TEM) induction, and Multi-channel Analysis of Surface Wave (MASW). The demonstration project was completed at a dry-stack CCR unit containing a variety of CCR ash, gypsum, and thin layers of drainage aggregate (limestone). During a single-day deployment, several geophysical survey tests were conducted in specific areas of …


Geopolymers For Construction And Mining: Material Characterization And Application Prospects, Radoslaw Pomykala, Gabriela Fuks May 2026

Geopolymers For Construction And Mining: Material Characterization And Application Prospects, Radoslaw Pomykala, Gabriela Fuks

World of Coal Ash Proceedings

Geopolymers have long been presented as an alternative to conventional concretes and cement-based binders, yet their practical use remains limited for various reasons. This paper examines both the material properties of such mixtures and their potential for broader application.

The study evaluated geopolymers produced from different types of fly ash, including typical siliceous ashes and ash with elevated CaO content. The influence of mixture components, such as solids content, activator type, and sample preparation and curing methods, on technological properties was investigated. Research covered fresh mixtures—rheological behavior and setting time—as well as hardened samples using mechanical testing, XRD, and SEM. …


Riki&Dolphin: Real Time Data Transmission From The Bottom Of A Cave To A Website, Luca Tringali, Giacomo Canciani Dr., Tecla Tripari, Alexander Debenjak, Caterina Bearzotti May 2026

Riki&Dolphin: Real Time Data Transmission From The Bottom Of A Cave To A Website, Luca Tringali, Giacomo Canciani Dr., Tecla Tripari, Alexander Debenjak, Caterina Bearzotti

International Journal of Speleology

Coming from over 10 years of experience in cave monitoring in northeast Italy, Gruppo Speleologico Talpe del Carso, has designed Riki and Dolphin: customizable, low cost, and easy to assemble tools for getting real time data transmission from the bottom of a cave, even underwater, to a webserver. Their use has been tested to monitor air temperature inside the Abisso Bonetti Cave (Classical Karst, Italy), proving for the first time that a cave in Gorizian Karst can systematically be colder than the outdoor temperature even in winter, recording an internal temperature even lower than 0°C. The Dolphin device can be …


Evolution Of Instrumentation Use For Ccr Unit Decision Making, Nick Mcclung, Victoria Bierwirth, Matt Bishop May 2026

Evolution Of Instrumentation Use For Ccr Unit Decision Making, Nick Mcclung, Victoria Bierwirth, Matt Bishop

World of Coal Ash Proceedings

Over the past decades, the power industry’s instrumentation needs and requirements have shifted to meet industry standards and regulations. In the early 2010s, piezometers and slope inclinometers were the primary types of instrumentation used to evaluate the stability of a CCR Unit. Some of the piezometers and slope inclinometers installed are still in use today to evaluate long-term stability for operations and closure. Since this time, additional instrument types were selected for installation including observation wells and temporary wells to further understand phreatic conditions within the CCR Unit. As utilities are faced with closures including removal of free liquids, data …


Evaluating The Properties Of Ohio Ponded Fly Ash For Reliable Use In Concrete Mixtures, Ayah Suliman May 2026

Evaluating The Properties Of Ohio Ponded Fly Ash For Reliable Use In Concrete Mixtures, Ayah Suliman

World of Coal Ash Proceedings

Concrete producers are under pressure to reduce the carbon footprint of concrete while maintaining a reliable supply of supplementary cementitious materials. Meanwhile, U.S. coal production in 2023 declined to less than half of its 2008 peak, significantly reducing the availability of fresh ASTM C618 compliant fly ash. At the same time Ohio contains more than 145 million cubic yards of coal combustion residuals stored in ponds, representing a large and underutilized source of potential fly ash for concrete applications. This study evaluates the suitability of harvested Ohio ponded fly ash for use in concrete through practical and specification-driven testing aligned …


Benefits Of Geophysical Imaging For Coal Combustion Residuals Management Unit Delineation, Gabriel Herbert May 2026

Benefits Of Geophysical Imaging For Coal Combustion Residuals Management Unit Delineation, Gabriel Herbert

World of Coal Ash Proceedings

Gabriel J. Hebert1, Gregory B. Byer1, Margaret Gentile1 1Arcadis U.S., Inc., 2839 Paces Ferry Road SE, Suite 1000, Atlanta, GA 30339 KEYWORDS: geophysical imaging, delineation, CCRMU ABSTRACT Under the 2024 Legacy CCR Rule detailed in 40 CFR Part 257, Section 75, all electric utility companies with a known legacy coal combustion residuals (CCR) surface impoundment are required to conduct a facility evaluation to identify the location, dimensions, and volumes of CCR placed and remaining on site and to assess structural stability. At a minimum, the presence or absence of CCR management units (CCRMUs) must be documented through a desktop records …


Extracting Rees From Refuse Pile Coal, Howard Mcclintic May 2026

Extracting Rees From Refuse Pile Coal, Howard Mcclintic

World of Coal Ash Proceedings

Concurrent Technologies Corporation (CTC) has a patented high temperature electric arc furnace (EAF) technology that reaches 4000-degree centigrade temperature(s). Such high temperatures are sufficient to extract each of the seventeen rare earth elements (REEs) from coal fly ash to ultimately manufacture diverse magnets. Neodymium iron boron magnets (NdFeB) are the strongest magnets produced, heretofore almost exclusively by the Chinese. For national security reasons, CTC has become part of the domestic supply chain, as an alternate to China. Scaling is the next hurdle, since our demonstration unit is operational. Nationwide, coal is decreasingly used as a fuel for generating electricity. However, …


Basin Ash Harvesting At The Brunner Island Station, Kyle Flynn May 2026

Basin Ash Harvesting At The Brunner Island Station, Kyle Flynn

World of Coal Ash Proceedings

Tribo-electrostatic separation has been used for the commercial beneficiation of coal combustion fly ash to produce a low carbon product for use as a cement replacement in concrete for over twenty-five years. With 24 separators in 18 coal-fired power plants and cement plants across the world, ST Equipment & Technology LLC’s (STET) patented electrostatic separator has been used to produce over 25 million tons of low carbon product that has been recycled for use in concrete or cement production. STET has developed and commercialized a new process for beneficiation of reclaimed fly ash from landfills and ponds that utilizes fly …


Adaptive Design And Execution In Ccr Pond Closure: A Case Study Of Technical And Regulatory Innovation, Jay Mokotoff, Angie Casbon-Scheller May 2026

Adaptive Design And Execution In Ccr Pond Closure: A Case Study Of Technical And Regulatory Innovation, Jay Mokotoff, Angie Casbon-Scheller

World of Coal Ash Proceedings

Closure by removal (CbR) of CCR impoundments presents complex challenges, particularly when unique hydrogeologic conditions exist. This presentation highlights the advance planning and ongoing closure of a Midwestern utility’s East Ash Pond (EAP), a relatively small facility with highly atypical characteristics. To comply with the CCR Rule, sluicing to the EAP ceased while the generating unit remained operational. Fly ash handling was converted to a dry system for beneficial reuse; however, wet sluicing of bottom ash continued. To avoid constructing a new regulated CCR impoundment, an innovative geotextile tube containment area (GTCA) was designed and implemented to capture bottom ash …


Psychiatry Meets Ai: Are Residents Ready?, Jacob De Castro, John Case May 2026

Psychiatry Meets Ai: Are Residents Ready?, Jacob De Castro, John Case

Rowan-Virtua Research Day

Artificial intelligence (AI) use is increasing in healthcare, but psychiatry residency training remains unstructured. In a 20-resident pilot survey, AI was frequently used for literature review and clinical support, with limited confidence and institutional guidance. We found most residents desired formal training and would use AI more if institutionally supported. Findings highlight a gap between rapid adoption and structured education.


Ai-Augmented Digital Auscultation For Point-Of-Care Screening Of Valvular Heart Disease: A Systematic Review And Meta-Analysis, Harshal Parmar, Akhila Archakam, Nikhila Archakam, Wesley Kim, Eduard Koman Md May 2026

Ai-Augmented Digital Auscultation For Point-Of-Care Screening Of Valvular Heart Disease: A Systematic Review And Meta-Analysis, Harshal Parmar, Akhila Archakam, Nikhila Archakam, Wesley Kim, Eduard Koman Md

Rowan-Virtua Research Day

Background: Valvular heart disease (VHD) affects >10% of adults aged 75+ yet remains underdiagnosed when asymptomatic due to declining auscultatory proficiency. AI-augmented digital auscultation offers a point-of-care screening solution, though no meta-analysis has pooled diagnostic accuracy across VHD subtypes in adults using echocardiography as the reference.

Methods: A systematic review and meta-analysis were conducted per PRISMA guidelines. PubMed, Embase, Cochrane, IEEE Xplore, and Scopus were searched without date restriction. Studies applying AI or machine learning to digital auscultation or phonocardiography for VHD classification in adults with echocardiographic reference and patient-level diagnostic metrics were included. Studies using only public datasets, pediatric …


Developing A Comprehensive Resource Guide For Caregivers Within The Area Agency On Aging, Aiden R. Murphy May 2026

Developing A Comprehensive Resource Guide For Caregivers Within The Area Agency On Aging, Aiden R. Murphy

Public Health Capstone Projects

This project developed a new universal caregiver resource guide for caregivers within the Area Agency on Aging, in order to improve resource navigation and workflow efficiency. Resources were collected, verified, and organized into a new, streamlined guide via the ARIA chatbot, covering multiple needs. Caregiver resources were collected and verified by the capstone student and mentor, Michael Kroeker, and organized into a centralized knowledge base within the ARIA chatbot. A mixed methods evaluation was conducted utilizing a 5-point Likert scale with three quantitative questions and one open-ended qualitative question. The data was given to the SeniorLine staff, who wanted to …


What History Shows: A Structural Account Of Fixed-Point Theory Formation, Griselda Poe May 2026

What History Shows: A Structural Account Of Fixed-Point Theory Formation, Griselda Poe

Publications and Research

Theory generation has long been subsumed under categories such as creativity, genius, and innovation. These categories do not distinguish assembly-based conceptual synthesis from fixed-point theory generation.

This paper makes that distinction explicit. The termination condition of assembly is external: data, citation, endorsement, usability. The termination condition of fixed-point theory generation is internal: consistency with internally held constraints, resolution of structural contradiction. The two operate under different processing conditions.

The historical record confirms this distinction. What Darwin, Einstein, Spinoza, and Kant produced was not assembly. Their processes involved unresolved branch retention and decomposition necessity, arriving at internally constrained fixed-point termination. Freud …


Air Quality, Atmospheric Pressure, And Migraine Presentations In The Emergency Department, James Espinosa, Alan Lucerna May 2026

Air Quality, Atmospheric Pressure, And Migraine Presentations In The Emergency Department, James Espinosa, Alan Lucerna

Rowan-Virtua Research Day

Background: Migraine is a leading cause of Emergency Department (ED) visits and global disability. Weather has long been reported by patients as a trigger, yet the literature remains inconsistent. Prior ED-based data demonstrated an association between higher mean barometric pressure and increased migraine presentations, without a relationship to short-term pressure change. Because high-pressure systems are frequently associated with atmospheric stagnation and pollutant accumulation, air quality may represent a biologically plausible mediator.

Objective: To examine the relationship between air quality and ED migraine presentations within the existing body of literature and to explore whether air quality may help explain previously observed …


Listening To The System: Reframing Emergency Department Noise: The Case For Noise As A Real-Time Operational Signal In A Complex Adaptive System (Cas), James Espinosa, Alan Lucerna, Henry Schuitema May 2026

Listening To The System: Reframing Emergency Department Noise: The Case For Noise As A Real-Time Operational Signal In A Complex Adaptive System (Cas), James Espinosa, Alan Lucerna, Henry Schuitema

Rowan-Virtua Research Day

Emergency Department (ED) noise has historically been framed as an occupational and environmental hazard requiring mitigation. And this is still true—but not complete. Early work focused on exposure reduction and spike identification. Subsequent mapping studies demonstrated spatial and temporal differentiation in ED acoustic load. We propose an expanded conceptual model: acoustic variability may function not only as a hazard, but also as a real-time signal of operational turbulence within the ED as a complex adaptive system (CAS). Drawing on human factors, alarm fatigue, resilience engineering, and complexity science, we synthesize existing literature and institutional experience to identify a critical gap—noise …


The Physics And Biology Of High-Risk Falls: Biomechanical Analysis And Physics Assists In Understanding Why The Threshold For High-Risk Was Lowered To 10 Feet, James Espinosa, Alan Lucerna May 2026

The Physics And Biology Of High-Risk Falls: Biomechanical Analysis And Physics Assists In Understanding Why The Threshold For High-Risk Was Lowered To 10 Feet, James Espinosa, Alan Lucerna

Rowan-Virtua Research Day

Background: Recent revisions to the National Guideline for the Field Triage of Injured Patients lowered the high-risk fall threshold from >20 feet  to >10 feet for all ages. Guideline changes are multifactorial and typically reflect epidemiologic registry data, injury severity trends, and systems-level performance feedback. However, biomechanical analysis assists in understanding the importance of the change.

Objective: To demonstrate that a 10-foot fall generates sufficient kinetic energy and deceleration forces to exceed structural tolerance thresholds in multiple human tissues, and to show that fundamental physics independently supports the recent trauma protocol change.

Methods: Application of gravitational motion equations (v = …


Genetic Analysis Of Triplicated Genes Affecting Sex-Specific Skeletal Deficits In Down Syndrome Model Mice, Kourtney Sloan, Kristina M. Piner, Pathum Randunu Nawarathna Kandedura Arachchige, Charles R. Goodlett, Yann Herault, Gayla R. Olbricht, Joseph M. Wallace, Randall J. Roper May 2026

Genetic Analysis Of Triplicated Genes Affecting Sex-Specific Skeletal Deficits In Down Syndrome Model Mice, Kourtney Sloan, Kristina M. Piner, Pathum Randunu Nawarathna Kandedura Arachchige, Charles R. Goodlett, Yann Herault, Gayla R. Olbricht, Joseph M. Wallace, Randall J. Roper

Mathematics and Statistics Faculty Research & Creative Works

Down syndrome (DS) is caused by the triplication of human chromosome 21 (Hsa21), resulting in skeletal insufficiency (low bone mineral density) and altered bone development. DS mouse models recapitulate these deficits, including sexual dimorphism in long bone alterations. Historically, Ts65Dn mice provided much of the insight behind DS-related skeletal deficits with ∼100 trisomic orthologous genes, but there are concerns about the genetic fidelity in this model due to the included triplication of genes not homologous to Hsa21. A new DS model, Ts66Yah, subtracted the non-Hsa21 homologous trisomic genes from Ts65Dn but has not been evaluated for long bone deficits. Comparing …


Research Instrumentation Center (Ric), Ryan Hilger, Purdue University Office Of Research May 2026

Research Instrumentation Center (Ric), Ryan Hilger, Purdue University Office Of Research

University Research Core Facility Boilerplate Descriptions

No abstract provided.


Toward The Salmon Prize: A Computational Certificate For The M5, M6, And M9 Equation Families Of Σ4(P3 × P3 × P3), John Trevino May 2026

Toward The Salmon Prize: A Computational Certificate For The M5, M6, And M9 Equation Families Of Σ4(P3 × P3 × P3), John Trevino

Theatre Faculty Publications

We present a computational certificate for three families of explicit polyno- mial equations whose zero locus contains the fourth secant variety σ4(P3×P3×P3) inside P63. The three families are: 192 degree-5 Strassen commutation equa- tions (M5); 160 degree-6 equations lifted from the Bates–Oeding generators of σ4(P2 × P2 × P3) via the Landsberg–Manivel–Friedland theorem (M6); and 64 degree-9 Ottaviani 9 × 9 determinant equations (M9). All 416 generators are explicit polynomials in the coordinate ring Z[Zijk | i, j, k ∈ {0, 1, 2, 3}]. We verify by exact integer arithmetic that every generator vanishes on rank-4 test tensors (six independent …


Predicting And Decoding Allosteric Binding Sites Using Protein Language Models And Structure-Based Machine Learning: An Energy Landscape-Guided Explainable Ai Framework, Kamila Riedlová, Vít Skrhák, William G. Gatlin, Max Ludwick, Lucas Turano, Marian Novotný, David Hoksza, Gennady M. Verkhivker May 2026

Predicting And Decoding Allosteric Binding Sites Using Protein Language Models And Structure-Based Machine Learning: An Energy Landscape-Guided Explainable Ai Framework, Kamila Riedlová, Vít Skrhák, William G. Gatlin, Max Ludwick, Lucas Turano, Marian Novotný, David Hoksza, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Computational prediction of allosteric binding sites in protein structures remains a persistent challenge, as these regulatory pockets evade detection by both sequence-based and structure-based algorithms. Both computational and physical origins of this predictive asymmetry remain insufficiently understood. In this study, we systematically examine the determinants of binding site predictability using a dual framework that integrates a fine-tuned protein language model and the structure-based method P2Rank as complementary tools probing a diverse data set of 453 human kinases, together with a physics-based interpretability layer derived from energy landscape frustration analysis. Both predictors exhibit a sharp and reproducible dichotomy on protein kinases, …


Propasafe-Hybrid: A Text-Based Hybrid Propaganda Detection Tool, Thomas Kimmeth, Avijit Roy, Vivek Sharma May 2026

Propasafe-Hybrid: A Text-Based Hybrid Propaganda Detection Tool, Thomas Kimmeth, Avijit Roy, Vivek Sharma

Publications and Research

Propagandistic content increasingly circulates through online news and social media, where readers often encounter it with limited scrutiny, highlighting the need for reliable and fine-grained detection. This paper introduces Propasafe-Hybrid, a sentence-level system that integrates a fine-tuned transformer classifier with LLM-based technique classification to identify, label, and explain specific propaganda strategies. The pipeline generates actionable outputs, including highlighted sentences, technique assignments, and concise rationales, so users can immediately understand why a sentence was flagged and how each label was determined. To control inference cost, Propasafe-Hybrid employs a cost-aware pre-filtering stage that forwards only high-likelihood sentences to LLMs, reducing token usage …


A Remote Sensing Approach To Identifying Zones Of Instability In Mine Tailings Impoundments Using Multi-Sensor Satellite Data, Arden K. Pierce May 2026

A Remote Sensing Approach To Identifying Zones Of Instability In Mine Tailings Impoundments Using Multi-Sensor Satellite Data, Arden K. Pierce

Honors Theses

Mine tailings impoundments are structures built to contain the chemical and sedimentary byproducts generated by ore extraction activities. In this common method of mining waste storage, the tailings can be pumped into containment ponds and held behind earthen embankments to prevent the release of hazardous substances into the surrounding environment. Monitoring environmental factors that influence the structural integrity of these impoundments is essential for identifying areas vulnerable to instability and failure. Soil moisture is a factor that can affect the stability of mine tailings impoundment structures. This study evaluates the relationship between satellite-derived soil moisture and surface deformation at mine …


Monitoring Groundwater Flow At Old Works Using Anisotropy, 3-D Electrical Geophysics, And Dem-Based Terrain Analysis, Yihaun Gao May 2026

Monitoring Groundwater Flow At Old Works Using Anisotropy, 3-D Electrical Geophysics, And Dem-Based Terrain Analysis, Yihaun Gao

Honors Theses

Groundwater flow in shallow heterogeneous environments is often difficult to characterize using a single geophysical method. This study applies an integrated approach combining azimuthal resistivity anisotropy, self-potential (SP) measurements, DEM-derived terrain indices, and three-dimensional electrical resistivity tomography (3-D ERT) to delineate preferential groundwater pathways at the Old Works Golf Course in Anaconda, Montana. Azimuthal anisotropy analysis from eighteen 2-D ERT profiles revealed a dominant directional dependence in electrical conductivity, indicating a structural or sedimentological control on subsurface flow. The anisotropy results indicate a preferred conductivity direction of approximately 200°–210° in azimuth (0° is north), suggesting that groundwater movement is guided …


Asymmetric Synthesis Of Borylated Amines Via Rhodium Catalyzed Hydroboration Of Allylamine Derivatives: Surprising Role Of Counterions And Accelerators, Rukshani Wickrama Arachchilage May 2026

Asymmetric Synthesis Of Borylated Amines Via Rhodium Catalyzed Hydroboration Of Allylamine Derivatives: Surprising Role Of Counterions And Accelerators, Rukshani Wickrama Arachchilage

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The Catalytic Asymmetric Hydroboration (CAHB) reaction is a valuable method for synthesizing chiral organoboron compounds. Nevertheless, key mechanistic details, including catalyst activation, ligand effects, and rate-determining steps, are difficult to generalize and remain not fully understood. Building on previous research from the Takacs group, this work explores acyclic N-acyl allylamines as substrates in rhodium-catalyzed hydroboration and investigates the formation of active catalysts from various rhodium precursors, the role of counterions (e.g. BF4, BArF-), ligand-to-metal ratios, and the impact of external fluoride additives (e.g. TBAT). Hydroboration of acyclic N-acyl allylamines achieves up to 90% yield and 99 : 1 …