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Full-Text Articles in Physical Sciences and Mathematics

Toward Vehicle-Agnostic Driving Signatures For Cognitive Impairment Prediction From Naturalistic Driving Data, Aadarsha Gopala Reddy May 2026

Toward Vehicle-Agnostic Driving Signatures For Cognitive Impairment Prediction From Naturalistic Driving Data, Aadarsha Gopala Reddy

McKelvey School of Engineering Graduate Student Theses & Dissertations

This thesis studies whether naturalistic driving data can help predict binary Clinical Dementia Rating (CDR) status while accounting for differences across vehicles. The final analytic dataset comprised 26,968 participant-weeks from 304 participants. Weekly driving features were derived from real-world telematics data and combined with four demographic covariates. Primary model comparisons used leave-one-participant-out (LOGO) cross-validation, with one individual held out at a time and pooled participant-level metrics used as the main reporting surface.

The main comparison includes six model families evaluated on the same dataset under a shared LOGO framework. Performance remained modest overall. GRU-DANN had the highest participant-level ROC AUC …


Largest 2-Regular Subgraphs In Complete S-Partite Graphs, Yiyang Jiang May 2026

Largest 2-Regular Subgraphs In Complete S-Partite Graphs, Yiyang Jiang

McKelvey School of Engineering Graduate Student Theses & Dissertations

In this thesis, we focus on the class of complete $S$-partite graphs, for $S$ an undirected graph possibly with self-loops, and address the problem of finding largest $2$-regular subgraphs of these graphs, which can be formulated as an integer linear program. Roughly speaking, a complete $S$-partite graph is obtained by replacing every single node of $S$ with a number of nodes, preserving the edge/non-edge relations of $S$. Our motivation in studying largest $2$-regular subgraphs is rooted in the structural systems theory, particularly in the problem of finding largest subnetworks that can sustain controllability or asymptotic stability of the corresponding subsystems. …


Kl Dra As A Benchmark Laboratory For Accretion-Disk Physics: Constraints From Tess And Ground-Based Surveys, Luis E. Salazar Manzano, Liliana E. Rivera Sandoval, Jean-Marie Hameury, Craig O. Heinke, Iwona Kotko, Thomas J. Maccarone, Manuel Pichardo Marcano May 2026

Kl Dra As A Benchmark Laboratory For Accretion-Disk Physics: Constraints From Tess And Ground-Based Surveys, Luis E. Salazar Manzano, Liliana E. Rivera Sandoval, Jean-Marie Hameury, Craig O. Heinke, Iwona Kotko, Thomas J. Maccarone, Manuel Pichardo Marcano

Physics & Astronomy Faculty Publications

We present the longest-term optical analysis of the AM CVn system KL Dra using ∼11 yr of monitoring from TESS and wide-field ground-based surveys. The continuous TESS coverage allows us to characterise its frequent outbursts with unprecedented detail, providing the first comprehensive study of an AM CVn during outbursts and enabling detailed modelling of these systems. The superoutbursts in KL Dra generally include a precursor and are followed by a series of rebrightenings after which a sequence of 3–4 large amplitude normal outbursts is observed. We fit parametric profiles to each superoutburst component (precursor, rise to plateau, plateau, and decay), …


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 …


Developing Narrative-Based Stem Learning Tool For K-6 Visually Impaired Students, Daniel Tsivkovski, Dylan Ravel, Jeffrey Kraskouskas, Brandon Foley, Maryam Etezad, Franceli Cibrian, Rajeev Joshi, Ariel Han May 2026

Developing Narrative-Based Stem Learning Tool For K-6 Visually Impaired Students, Daniel Tsivkovski, Dylan Ravel, Jeffrey Kraskouskas, Brandon Foley, Maryam Etezad, Franceli Cibrian, Rajeev Joshi, Ariel Han

Student Scholar Symposium Abstracts and Posters

This research develops a free, accessible web application that enables K-6 students who are blind or visually impaired (BVI) to learn STEM concepts using refreshable braille displays. Currently, most online learning tools are not designed for BVI students, creating a significant educational barrier.

The application interfaces with commercial braille displays and uses narrative-based learning to make STEM content approachable and engaging. By presenting material as personalized interactive stories generated with the help of Artificial Intellligence (AI), students can connect with concepts while developing braille reading skills. The curriculum design prioritizes accessibility through the Accessible Rich Internet Applications (ARIA) standards and …


Freshman 15? Freshman 50?? The Reality Of Daily Life Habits Of A First Year College Student, Gregorio R. Salgado May 2026

Freshman 15? Freshman 50?? The Reality Of Daily Life Habits Of A First Year College Student, Gregorio R. Salgado

Student Scholar Symposium Abstracts and Posters

This project presents a personal data tracking study in which I collected daily self-reported metrics over the course of the Spring semester using Excel. The variables tracked include sleep duration, caloric intake, screen time, social media usage, phone checks per day, family communication, and personal spending. The goal of this project is to identify meaningful patterns and correlations between daily habits and personal well-being.

Data was collected through a combination of manual logging and smartphone-generated daily reports. This study explores potential relationships between variables such as sleep duration and social media usage, as well as the association between family communication …


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 …


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.


Improving Semantic Precision In Text-To-Image Diffusion Models Via Latent-Space Optimization And Semantically-Parsed Evaluation, Mohammad Rouie Miab May 2026

Improving Semantic Precision In Text-To-Image Diffusion Models Via Latent-Space Optimization And Semantically-Parsed Evaluation, Mohammad Rouie Miab

McKelvey School of Engineering Graduate Student Theses & Dissertations

Text-to-image diffusion models can produce visually impressive images from natural-language prompts, but they often fail to satisfy the detailed semantic constraints expressed in compositional prompts. Typical failure modes include omitted objects, merged entities, incorrect quantities, incorrect attribute binding, and leakage of one entity's attributes onto another. This thesis studies the problem of semantic precision in text-to-image generation: how faithfully a generated image satisfies the structured meaning of its prompt.   The thesis makes two linked contributions. First, it presents a training-free inference-time refinement method for diffusion-based image generation. The method operates directly in latent space during denoising and uses noun-phrase-aware cross-attention …


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 …


Does Your Sleep Really Matter?, Kristy Riddle May 2026

Does Your Sleep Really Matter?, Kristy Riddle

Student Scholar Symposium Abstracts and Posters

In this project, I am tracking 10 of my daily statistics revolving around my routine. I am using an Oura Ring to help accomplish some of the statistics. These include: readiness score, sleep score, screen time on cell phone, time spent on social media, steps taken, stress levels, restorative time, pages read, homework time spent, and oz of water consumed. I will be utilizing Excel for my data and will have around 3 months worth of statistics. hope to learn more about my levels of efficient sleep and how I can better improve my motivation as a student. This project …


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 …


Coal Ash-Derived Aluminosilicate Precursors: A Chemical Engineering Approach To Geopolymer Characterization, Hafiz Abdul Basit, Abdullah Bashir, Abdur Raafey May 2026

Coal Ash-Derived Aluminosilicate Precursors: A Chemical Engineering Approach To Geopolymer Characterization, Hafiz Abdul Basit, Abdullah Bashir, Abdur Raafey

World of Coal Ash Proceedings

The chemical and microstructural evaluation of coal-derived aluminosilicate precursors is critical for understanding their suitability in advanced construction material systems. In this study, a characterization of Class F fly ash, ground granulated blast furnace slag (GGBFS), and Silica Fumes (SF) was conducted to elucidate their morphological and elemental features. Scanning Electron Microscopy (SEM) was used to assess particle morphology and surface characteristics (porosity, particle diameter, particle geometry), and Energy-Dispersive X-ray Spectroscopy (EDS) to determine elemental composition and distribution. The analysis revealed distinct morphological and compositional differences among the precursors, including spherical fly ash particles, calcium-rich slag phases, and ultra-fine silica …


State Permitting Program Update, Jessica Reiss May 2026

State Permitting Program Update, Jessica Reiss

World of Coal Ash Proceedings

State Permitting Program Update Jessica L. Reiss, Barnes & Thornburg LLP, 11 South Meridian Street, Indianapolis, IN 46204 KEYWORDS: states, permitting, permit program, rulemaking ABSTRACT At the end of 2016, the United States Congress authorized states to establish permit programs for coal combustion residuals (CCR) surface impoundments and landfills.[1] Since then, several states have established such programs, and the United States Environmental Protection Agency (U.S. EPA) has approved programs for Oklahoma,[2] Georgia,[3] Texas,[4] and North Dakota,[5] proposed approval for Wyoming,[6] and denied approval for Alabama.[7] Other states, such as Indiana,[8] are actively working through the state rulemaking process and plan …


Zero-Waste And High-Value Valorization Of Coal Combustion Residues Via Critical Minerals Recovery And Cementitious Materials Production, Hongyan Ma May 2026

Zero-Waste And High-Value Valorization Of Coal Combustion Residues Via Critical Minerals Recovery And Cementitious Materials Production, Hongyan Ma

World of Coal Ash Proceedings

Coal combustion residues (CCRs) pose significant environmental and disposal challenges, yet they also represent an untapped resource rich in aluminosilicates and critical minerals. This work presents a zero-waste, high-value valorization pathway that integrates critical mineral recovery with the production of cementitious materials. Advanced separation and extraction techniques are employed to recover strategically important elements such as gallium and rare earths, while the mineral-rich residues are simultaneously processed into supplementary cementitious materials (SCMs) for blended cements and concretes. This integrated approach not only offsets the environmental burden of CCR disposal but also supports domestic supply chains of critical minerals and reduces …


Revolutionizing Closure Systems: The Performance Advantages Of Structured Geomembranes, Scott Perugia May 2026

Revolutionizing Closure Systems: The Performance Advantages Of Structured Geomembranes, Scott Perugia

World of Coal Ash Proceedings

Coal combustion residual (CCR) containment facilities have traditionally been closed using methods that have changed little over several decades, but structured geomembranes are now reshaping closure design by improving slope stability, increasing interface friction, enhancing drainage, and providing long-term durability. Two systems are emerging as leading solutions: a structured geomembrane paired with a geotextile and vegetative cover, and a structured geomembrane paired with engineered turf. This presentation compares these approaches using field performance data, laboratory testing, and lessons learned, with emphasis on key factors such as infiltration control, drainage efficiency, slope stability, constructability, and regulatory compliance. The engineered turf system …


Developing Concentrated Brines / Salt Slurries For Disposal Of Coal Ash Wastewaters., Lance Edling May 2026

Developing Concentrated Brines / Salt Slurries For Disposal Of Coal Ash Wastewaters., Lance Edling

World of Coal Ash Proceedings

If coal ash wastewater is not fully concentrated to the greatest extent possible, then this results in greater disposal volumes and costs. However, concentrating a wastewater stream high in scaling compounds can be difficult. Membranes are prone to scale and Vacom thermal systems are higher in operating cost. This presentation will discuss the need to minimize disposal volumes by concentrating wastewater that is readily prone to scale and foul. The discussion will present past project examples of waste streams that were concentrated until salt crystals formed and the method used to minimize fouling and scaling during the concentration process. In …


Recinis™ Wet Beneficiation Process For Landfilled Coal Ash, Tim Sambrook May 2026

Recinis™ Wet Beneficiation Process For Landfilled Coal Ash, Tim Sambrook

World of Coal Ash Proceedings

The decline of coal-fired power generation has reduced fresh “Run-of-Station” ash availability, increasing reliance on reclaimed ash from landfills to meet supplementary cementitious material (SCM) demand. This shift has lowered OPC replacement rates and raised concrete costs due to inconsistent ash quality. ReCinis™ offers a low-capex wet beneficiation solution for landfill-aged, saturated, and variable-quality coal ash. With over 5 billion tons of ash impounded in the U.S., this process enables long-term supply security where dry beneficiation is unsuitable. Combining proven mineral processing techniques with coal ash expertise, ReCinis™ can be deployed as a 150,000 tpa skid-mounted plant or scaled to …


Lessons Learned From A Full-Scale Discrete In-Situ Stabilization Project For Ccr Impoundment Closure, Tony Moran, Paul Jennings, Jacob Susser, Tim Silar May 2026

Lessons Learned From A Full-Scale Discrete In-Situ Stabilization Project For Ccr Impoundment Closure, Tony Moran, Paul Jennings, Jacob Susser, Tim Silar

World of Coal Ash Proceedings

ENTACT, in collaboration with Silar Services, Inc., the patent holder of Discrete In-Situ Solidification (DISS) technology, has successfully performed a full-scale implementation of DISS in a Coal Combustion Residual (CCR) impoundment. DISS hydraulically isolates ash from surrounding groundwater by constructing a low-permeability barrier at the impoundment bottom to treat a layer of ash and tying into underlying natural soil layers. DISS enables targeted stabilization within a designated treatment zone, minimizing the disturbance of overburden compared to traditional excavation methods and reducing the use of costly cementitious reagents. The process starts with Reagentless Drilling of the overburden CCR utilizing a specialized …


From Clogs To Compliance: Overcoming Persistent Leachate Head Issues In Ccr Landfills, Breanne Kahnk, Zachary Bauman May 2026

From Clogs To Compliance: Overcoming Persistent Leachate Head Issues In Ccr Landfills, Breanne Kahnk, Zachary Bauman

World of Coal Ash Proceedings

State and federal regulations require that landfills, including coal combustion residual (CCR) landfills, be designed and operated to maintain leachate head levels of less than 30 centimeters (approximately 1 foot). While proper leachate collection system design and routine maintenance are critical for meeting this requirement, challenges such as clogging of drainage media, pipes, fittings and/or pipeline perforations, settlement of collection pipes, and breaks in the piping system can lead to elevated leachate levels, posing risks to compliance and long-term system performance. TRC will provide an overview of leachate collection system regulatory requirements along with design, operation, and maintenance strategies that …


Plasma Coal Ash Processing For Enhanced Recovery Of Rare Earth Elements & Precious Metals: Proven From R&D To Commercial Plants, George Paskalov, Victoria Campbell, Jason Honigberg May 2026

Plasma Coal Ash Processing For Enhanced Recovery Of Rare Earth Elements & Precious Metals: Proven From R&D To Commercial Plants, George Paskalov, Victoria Campbell, Jason Honigberg

World of Coal Ash Proceedings

Our Radio-frequency Plasma System is an ash pretreatment before the application of extractive metallurgy and addresses current elemental, methodological, and technological limitations of complex and refractory coal ash. Our system data shows from 10-20% improved recovery, to 9x-100x. RFP can access all metals contained in coal ash. Our focus is not on the alteration of established methodologies, such as cyanidation for non-refractory ore, which has a proven return and capacity to achieve target revenue at-scale. Using the RFP systems, no waste is created, overburden can be more easily dealt with, and no metal content will be left behind. We assert …


Probing The Critical Element Chemistry Of Coal-Combustion Fly Ash: Electron Microbeam Investigations Of The Spent Ash From The Pilot-Scale Acid Extraction Of Rare Earth Elements From A Beneficiated Kentucky Fly Ash, James Hower May 2026

Probing The Critical Element Chemistry Of Coal-Combustion Fly Ash: Electron Microbeam Investigations Of The Spent Ash From The Pilot-Scale Acid Extraction Of Rare Earth Elements From A Beneficiated Kentucky Fly Ash, James Hower

World of Coal Ash Proceedings

Fly ash derived from the combustion of an eastern Kentucky high volatile bituminous coal blend was beneficiated to yield a <75-μm product with a reduction in the carbon and spinels and reacted with a strong acid in a pilot-scale unit to extract rare earth elements. Electron microscopy showed a wide range of rare earth-bearing minerals. The acid-extracted fly ash had a rim that was depleted in REE and in most other elements except silicon.


Standardization Of Coal Ash Testing, Classification, And Harvesting, Benjamin Gallagher, Chris Frishcosy, Eric Hageman May 2026

Standardization Of Coal Ash Testing, Classification, And Harvesting, Benjamin Gallagher, Chris Frishcosy, Eric Hageman

World of Coal Ash Proceedings

Standards such as product specifications, test methods, practices and guides play a crucial role in supporting both commerce and science. Standardization helps build consistency and reliability whether it pertains to the performance of an ingredient in a product or in the measurement of a material characteristic. Coal combustion products, such as coal ash and synthetic gypsum, exhibit unique characteristics and many standard have been developed to characterize these materials and support their beneficial use. ASTM is a voluntary, consensus-based organization, and publishes many standards related to coal combustion products. Currently, there are seven ASTM standards related to chemical analysis of …