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Articles 13381 - 13410 of 294555

Full-Text Articles in Physical Sciences and Mathematics

Dataset Description, Bradley M. Ratliff Jul 2025

Dataset Description, Bradley M. Ratliff

Model Desert Terrain Monochromatic DoT Dataset

Polarimetric dataset containing data collected within the Automated Remote Sensing Solar Simulation Lab at the University of Dayton. The data were collected using a visible monochromatic division-of-time imaging polarimeter. A model desert terrain model was constructed and imaged for eight different scenarios consisting of different model panel and vehicle targets. The dataset is parameterized across different sensor, scene, and illumination geometries that mimic outdoor solar irradiance conditions.


Behavioral Responses Of The California Two-Spot Octopus Octopus Bimaculoides To Changes In Color And Sound, Sofia I. Ramirez, Nathalie Reyns Jul 2025

Behavioral Responses Of The California Two-Spot Octopus Octopus Bimaculoides To Changes In Color And Sound, Sofia I. Ramirez, Nathalie Reyns

McNair Summer Research Program

Recreational and commercial boat activity, military and construction operations, and seismic surveys among other human activities produce excessive sound that is classified as anthropogenic noise. Because the intensity and frequency of anthropogenic noise is often higher than that of natural underwater acoustic stimuli, marine animals may experience physiological damage to their sound-detecting organs which in turn, affects their communication and orientation abilities. In our study, we aimed to analyze the differences in behaviors exhibited by the California two-spot octopus (Octopus bimaculoides) when exposed to various volumes of noise at 54 Hz. To further investigate behavioral changes under varying conditions, we …


Energetic And Economic Aspects Of Rebound, Part Ii: Applications Of The Framework, Matthew Kuperus Heun, Gregor Semieniuk, Paul Brockway Jul 2025

Energetic And Economic Aspects Of Rebound, Part Ii: Applications Of The Framework, Matthew Kuperus Heun, Gregor Semieniuk, Paul Brockway

University Faculty Publications and Creative Works

Widespread implementation of energy efficiency is a key greenhouse gas emissions mitigation measure, but rebound can ‘‘take back’’ energy savings. However, the absence of solid analytical foundations hinders empirical determination of rebound magnitudes. In Part I, we developed foundations of a rigorous, analytical, consumer-sided rebound framework that is approachable for both energy analysts and economists. In this paper (Part II), we develop energy, expenditure, and consumption planes, a novel, mutually consistent, and numerically precise way to visualize and illustrate rebound. Further, we operationalize the macro factor (k) for macroeconomic rebound. Using the framework and rebound planes, we calculate and show …


Utahns’ Awareness Of The Drying Up Of The Great Salt Lake, Ashley Young Jul 2025

Utahns’ Awareness Of The Drying Up Of The Great Salt Lake, Ashley Young

Utah People and Environment Poll (UPEP)

The Great Salt Lake provides several benefits for the state of Utah. It supports industry, recreational activities, and aquaculture. It also provides wetland habitat to twelve million migratory birds.1 Due to drought induced by climate change and human water use, the lake has been shrinking rapidly in a process known as desiccation. The desiccation threatens the lake’s economic and ecological benefits while also posing other potential challenges. Dust from the dry lakebed may also cause health challenges for humans, as the dust contains harmful amounts of arsenic, lithium, copper, and other metals.2

Utah’s ability to combat desiccation of …


Lanthanum-Based Nanoparticles: A Promising Frontier In Antimicrobial Applications, Ikhazuagbe H. Ifijen, Peter Agyemang, Emmanuel Faderin, Lovelyn Oyinyechi Odo, Emmanuel Ikechukwu Okeke, Divine Ifechukwu Onugha, Stella Eberechi Obuba, Obembe Oluwafunke, Chinyem Ogochukwu Jul 2025

Lanthanum-Based Nanoparticles: A Promising Frontier In Antimicrobial Applications, Ikhazuagbe H. Ifijen, Peter Agyemang, Emmanuel Faderin, Lovelyn Oyinyechi Odo, Emmanuel Ikechukwu Okeke, Divine Ifechukwu Onugha, Stella Eberechi Obuba, Obembe Oluwafunke, Chinyem Ogochukwu

Michigan Tech Publications

Lanthanum-based nanoparticles have garnered significant attention for their potential in antimicrobial applications due to their unique properties and mechanisms of action. This review explores the antimicrobial efficacy of various lanthanum-based nanoparticles, including La2O3, La(OH)3, and LaF3, highlighting their mechanisms of action such as disruption of microbial cell walls, generation of reactive oxygen species (ROS), and interference with microbial DNA and protein synthesis. Despite their promising attributes, several challenges hinder their practical application, including limited understanding of their mechanisms, concerns over biocompatibility and toxicity, and difficulties in scaling up production. Emerging trends in nanoparticle research, such as surface functionalization, smart delivery …


Bicomplex Hardy Classes Of Solutions To Beltrami Equations And The Schwarz Boundary Value Problem, William L. Blair Jul 2025

Bicomplex Hardy Classes Of Solutions To Beltrami Equations And The Schwarz Boundary Value Problem, William L. Blair

Math Faculty Publications and Presentations

We define Hardy classes of bicomplex-valued functions on the complex unit disk which solve bicomplex versions of the Beltrami and related equations. Using representations in terms of their complex-valued counterparts, we show these bicomplex-valued functions recover the boundary behavior associated with the classic holomorphic Hardy spaces. This work generalizes known results for complex-valued functions and continues recent work in the setting of bicomplex analogues of Hardy spaces of both holomorphic and generalized analytic functions. Also, we show Schwarz and Dirichlet boundary value problems associated with the bicomplex Beltrami equation are solvable and provide solution formulas.


Standard Operating Procedures For The Laser Particle Size Analysis Of Terrigenous Sediments And Soils, Sandra Passchier Jul 2025

Standard Operating Procedures For The Laser Particle Size Analysis Of Terrigenous Sediments And Soils, Sandra Passchier

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This report details the preferred standard operating procedures for use of the Malvern Mastersizer 3000 (MS 3000) laser particle sizer in the analysis of terrigenous sediments and soils. Materials with median grain size < 500 µm can be measured on the MS3000. Preparation methods of sediment and soil samples before placing them in the laser particle sizer are described and the details of and rational behind the instrument standard operating protocols.


West Antarctic Ice Retreat And Paleoceanography In The Amundsen Sea In The Warm Early Pliocene, Sandra Passchier, Claus-Dieter Hillenbrand, Sidney R. Hemming, Werner Ehrmann, Thomas Frederichs, Steven M. Bohaty, Ronald Leon, Olga Libman-Roshal, Lisbeth Mino-Moreira, Karsten Gohl, Julia S. Wellner Jul 2025

West Antarctic Ice Retreat And Paleoceanography In The Amundsen Sea In The Warm Early Pliocene, Sandra Passchier, Claus-Dieter Hillenbrand, Sidney R. Hemming, Werner Ehrmann, Thomas Frederichs, Steven M. Bohaty, Ronald Leon, Olga Libman-Roshal, Lisbeth Mino-Moreira, Karsten Gohl, Julia S. Wellner

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Mass loss from polar ice sheets is poorly constrained in estimates of future global sea-level rise. Today, the marine-based West Antarctic Ice Sheet is losing mass at an accelerating rate, most notably in the Thwaites and Pine Island glacier drainage basins. Early Pliocene surface temperatures were about 4 °C warmer than preindustrial and maximum sea level stood ~20 m above present. Using data from a sediment archive on the Amundsen Sea continental rise, we investigate the impact of prolonged Pliocene ocean warmth on the ice-sheet−ocean system. We show that, in contrast to today, during peak ocean warming ~4.6 − 4.5 …


Modeling The Impact Of Explosive Volcanism On Biogeochemical Cycling At The Peak Of The Late Paleozoic Icehouse, Lily S. Pfeifer, Qingting Wu, Ying Cui, Gerilyn S. Soreghan Jul 2025

Modeling The Impact Of Explosive Volcanism On Biogeochemical Cycling At The Peak Of The Late Paleozoic Icehouse, Lily S. Pfeifer, Qingting Wu, Ying Cui, Gerilyn S. Soreghan

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The peak of the Late Paleozoic Ice Age (LPIA) coincided with atmospheric carbon dioxide (pCO2) lows, and large-magnitude fluctuations in glacial-interglacial pCO2, but the driver(s) for pCO2 drawdown at this time remain debated. Backed by parameters for the frequency and magnitude of Late Carboniferous volcanism derived from the rock record, we apply an intermediate complexity Earth system model to evaluate the biogeochemical impacts of ash-borne nutrients from frequent (decadal) and explosive silicic volcanism on nutrient cycling ca. 310–300 Ma. Results show that volcanic perturbations result in negligible changes in marine particulate organic carbon export concurrent with sustained increases in pCO2 …


Urbanization In Resource-Based County-Level Cities In China: A Case Study Of New Urbanization In Wuan City, Hebei Province, Jianguang Hou, Danlin Yu, Hao Song, Zhiguo Zhang Jul 2025

Urbanization In Resource-Based County-Level Cities In China: A Case Study Of New Urbanization In Wuan City, Hebei Province, Jianguang Hou, Danlin Yu, Hao Song, Zhiguo Zhang

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study investigates the complex dynamics of new-type urbanization in resource-based county-level cities, using Wuan City in Hebei Province, China, as a representative case. As China pursues a high-quality development agenda, cities historically dependent on resource extraction face profound challenges in achieving sustainable and inclusive urban growth. This research employs a multi-method approach—including Theil index analysis, industrial shift-share analysis, a Cobb–Douglas production function model, and a composite urbanization index—to quantitatively diagnose the constraints on Wuan’s development and assess its transformation efforts. Our empirical results reveal a multifaceted situation: while the urban–rural income gap has narrowed, rural income streams remain fragile. …


Enhancing Graph Representation Learning Through Self-Supervision: An Augmentation Perspective, Jianyuan Bo Jul 2025

Enhancing Graph Representation Learning Through Self-Supervision: An Augmentation Perspective, Jianyuan Bo

Dissertations and Theses Collection (Open Access)

Graph representation learning has become fundamental in various domains, from social networks to molecular structures, enabling extraction of meaningful patterns from graph-structured data. While deep learning approaches, particularly graph neural networks, have shown promising results, their effectiveness is often limited by the scarcity of labeled data. This challenge is particularly acute in graph domains where annotation requires specialized expertise and is prohibitively expensive. Self-supervised learning has emerged as a promising direction to address this limitation by creating auxiliary tasks from unlabeled data, with augmentation strategies playing a crucial role in their success.

Current graph self-supervised learning methods face several critical …


Syntax-Enhanced Boundary-Aware Named Entity Recognition Model, Chuanming Yu, Bin Deng, Zhengang Zhang Jul 2025

Syntax-Enhanced Boundary-Aware Named Entity Recognition Model, Chuanming Yu, Bin Deng, Zhengang Zhang

Journal of Scientific Information Research

[Purpose/significance] This study addresses the issue of inadequate perception of entity boundaries in traditional character-level modeling-based named entity recognition models by integrating syntax information containing entity boundary features into the task using a multi-head graph attention network with dense connections. This integration enhances the effectiveness of named entity recognition.

[Method/process] This study proposes a Syntax-enhanced Boundary-aware Named Entity Recognition Model (SynBNER), which utilizes BERT for text semantic representation and integrates syntax information using a dense-connected graph attention network. This integration incorporates implicit entity boundary information from syntax information into word representations, thereby enhancing the model's entity boundary perception capability.

[Result/conclusion] …


Investigating Contaminant Removal From Water Using Polymeric Alginate/Tio2 And Pla/Tio2 Nanocomposites, Tahzjayee Gaymon, Sarah Nealy, Aliaksandr Kraskouski, Eugenia Kharlampieva Jul 2025

Investigating Contaminant Removal From Water Using Polymeric Alginate/Tio2 And Pla/Tio2 Nanocomposites, Tahzjayee Gaymon, Sarah Nealy, Aliaksandr Kraskouski, Eugenia Kharlampieva

Expo Student Presentations

2025 Summer Expo Poster Presentation

  • Physical & Applied Sciences


Iowa Waste Reduction Center Newsletter, July 2025, University Of Northern Iowa. Iowa Waste Reduction Center. Jul 2025

Iowa Waste Reduction Center Newsletter, July 2025, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Contents:

--- 150th Anniversary & Homecoming Kickoff
--- SQG re-notification requirement
--- Introducing the Food, Beverage & Organics Team
--- A Historic First in Corrosion Control
--- Important Reminders
--- Industry News


Groundwater In Nebraska, Troy E. Gilmore, Jesse T. Korus Dr. Jul 2025

Groundwater In Nebraska, Troy E. Gilmore, Jesse T. Korus Dr.

Conservation and Survey Division: Faculty and Staff Publications

What is groundwater? Groundwater is water that fills and moves between spaces in underground rocks, gravel, sand, or other materials.


Synthesis Of Inorganic Actinide Compounds With Neptunium, Plutonium, And Americium, Travis Kelly Deason Jul 2025

Synthesis Of Inorganic Actinide Compounds With Neptunium, Plutonium, And Americium, Travis Kelly Deason

Theses and Dissertations

There is a rush of countries around the world making the switch to greener energy sources. Nuclear energy power plants are an integral part of the shift from fossil fuels, but there are concerns over the best way to handle nuclear waste. Most of the nuclear waste is currently disposed of by incorporating the waste into a glass form through vitrification, but research into alternative waste forms, such as promising crystalline materials, could provide a more robust method of containment. Research on actinide materials is lacking due to the dangers of working with radioactive material and there are few labs …


2025 July - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University Jul 2025

2025 July - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

Hi All,

The main story for July was the high heat and humidity that spread across the state for the second half of the month. Most counties in the state saw at least 1 day with a heat advisory or extreme heat warning issued by the National Weather Service due to a combination of high temperatures and humidity that sent heat index values above advisory/warning criteria. The western half of the state saw higher heat index values and were impacted by the heat wave for a longer period of time than the eastern half of the state. Some part of …


Map Of The Thickness Of Ordovician Shales Across The Kentucky-Tennessee Mineral District (Ktmd), John B. Hickman, Alex M. Washburn, Georgina Lukoczki Jul 2025

Map Of The Thickness Of Ordovician Shales Across The Kentucky-Tennessee Mineral District (Ktmd), John B. Hickman, Alex M. Washburn, Georgina Lukoczki

Research Data--KGS

The deposits of critical minerals have been found in metalliferous shales. To aid in critical mineral assessments of the Ordovician Shales in the Kentucky-Tennessee Mineral District (KTMD), this research project produced a map (digital GIS dataset) of the thickness (isopach) of the combined Upper Ordovician shale interval across the region. The subsurface input data are from oil/gas well records and exploratory mineral core. Well and core records for the KTMD were acquired from the state surveys of Tennessee and Kentucky. Along with the GIS files, a summary table of the 594 well and core data points used to produce this …


Performance Comparison Of Quantum And Classical Machine Learning Models For Chronic Kidney Disease Prediction, Parama Sridevi, Paramita Basak Upama, Masud Rabbani, Sheikh Iqbal Ahamed Jul 2025

Performance Comparison Of Quantum And Classical Machine Learning Models For Chronic Kidney Disease Prediction, Parama Sridevi, Paramita Basak Upama, Masud Rabbani, Sheikh Iqbal Ahamed

Computer Science Faculty Research and Publications

In this study, we develop and compare quantum and classical machine learning-based chronic kidney disease prediction models. We used the "Chronic_Kidney_Disease Data Set" of the UCI Machine Learning Repository. We performed data preprocessing and applied feature engineering techniques to select the best features. We developed two quantum machine learning-based models and two classical machine learning-based models. We used a hybrid classical-quantum environment for building quantum machine learning models. Finally, we compared the performances of all four models. We found that the Quantum Support Vector Machine performs best among the quantum models. The model’s accuracy was 95% with a k-fold cross-validation …


Eeg Based Real Time Classification Of Consecutive Two Eye Blinks For Brain Computer Interface Applications, Masud Rabbani, Nafi Us Sabbir Sabith, Anubhav Parida, Iysa Iqbal, Sayed Mashroor Mamun, Rumi Ahmed Khan, Farhad Ahmed, Sheikh Iqbal Ahamed Jul 2025

Eeg Based Real Time Classification Of Consecutive Two Eye Blinks For Brain Computer Interface Applications, Masud Rabbani, Nafi Us Sabbir Sabith, Anubhav Parida, Iysa Iqbal, Sayed Mashroor Mamun, Rumi Ahmed Khan, Farhad Ahmed, Sheikh Iqbal Ahamed

Computer Science Faculty Research and Publications

Human eye blinks are considered a significant contaminant or artifact in electroencephalogram (EEG), which impacts EEG-based medical or scientific applications. However, eye blink detection can instead be transformed into a potential application of brain–computer interfaces (BCI). This study introduces a novel real-time EEG-based framework for classifying three blink states: no blink, single blink, and two consecutive blinks in one model. EEG data were collected from ten healthy participants using an 8-channel wearable headset under controlled blinking conditions. The data were preprocessed and analyzed using four feature extraction techniques: basic statistical, time-domain, amplitude-driven, and frequency-domain methods. The most significant features were …


The Ethics Of Consent: Reflecting On The Case Of R/Changemyview, Casey Fiesler, Jessica Vitak, Michael Zimmer Jul 2025

The Ethics Of Consent: Reflecting On The Case Of R/Changemyview, Casey Fiesler, Jessica Vitak, Michael Zimmer

Computer Science Faculty Research and Publications

The SIGCHI Research Ethics Committee was established in 2016 in recognition of how the shifting technological landscape has complicated research ethics in HCI. Our research community has also taken up the call to help understand and guide this complex space, examining topics such as research taking place on online platforms without explicit consent, the use of bots as confederates in field experiments, debriefing for large-scale experiments, HCI research that involves or implicates marginalized populations, and ethical considerations for studying social media platforms such as Reddit.


Evaluating The Influence Of Carbon Quantum Dots On Starch-Based Bioplastics: Toward Potential Food Packaging Applications, Shima Jafarzadeh, Mitra Golgoli, Zeinab Qazanfarzadeh, Mehrdad Forough, Peng Wu, Wendy Timms, Colin J. Barrow, Minoo Naebe, Masoumeh Zargar Jul 2025

Evaluating The Influence Of Carbon Quantum Dots On Starch-Based Bioplastics: Toward Potential Food Packaging Applications, Shima Jafarzadeh, Mitra Golgoli, Zeinab Qazanfarzadeh, Mehrdad Forough, Peng Wu, Wendy Timms, Colin J. Barrow, Minoo Naebe, Masoumeh Zargar

Research outputs 2022 to 2026

Developing biodegradable food packaging films is crucial for reducing dependence on petroleum-based plastics. In this study, nitrogen-doped carbon quantum dots (CDs) were synthesized from citric acid and ethylenediamine via hydrothermal treatment and incorporated into sago starch films at concentrations of 0.5 %, 1 %, 3 %, and 4 % w/w of total solids using a solution casting method. The effects of CDs on structural, thermal, antioxidant, optical, and physicochemical properties were systematically investigated. CD addition enhanced the UV-shielding ability of the films. At 4 % CD content, UV transmittance decreased by 56.4 % (UVA), 66.7 % (UVB), and 73.9 % …


Real-World Continuous Smartwatch-Based User Authentication, N. Al-Naffakh, N. Clarke, F. Li, P. Haskell-Dowland Jul 2025

Real-World Continuous Smartwatch-Based User Authentication, N. Al-Naffakh, N. Clarke, F. Li, P. Haskell-Dowland

Research outputs 2022 to 2026

User authentication is often regarded as the "gatekeeper"of cyber security. It has, however, long suffered from significant usability issues that have resulted in research focussing upon frictionless and transparent biometric approaches. Activity-based user authentication - a technique that authenticates a user by what they are physically doing at a specific point in time has attracted significant attention, particularly due to the increasing popularity of smartwatches. This research aims to overcome limitations in prior work by exploring the viability of the approach in real-world conditions. The study presents two principal experiments, one focused upon a constrained environment to provide a control …


Winds Of Change: Charting A Pathway To Ecosystem Monitoring Using Airborne Environmental Dna, Rachel L. Tulloch, Clare I.M. Adams, Matthew A. Barnes, Elizabeth L. Clare, Henrik C. Van De Ven, Andrew Cridge, Francisco Encinas-Viso, Kristen Fernandes, Dianne M. Gleeson, Erin Hill, Anna J.M. Hopkins, Anna M. Kearns, Gracie C. Kroos, Anna J. Macdonald, Francesco Martoni, Angela Mcgaughran, Todd G.B. Mclay, Linda E. Neaves, Paul Nevill, Andrew Pugh, Kye J. Robinson, Fabian Roger, Tracey V. Steinrucken, Mieke Van Der Heyde, Cecilia Villacorta-Rath, Jenny Vivian Jul 2025

Winds Of Change: Charting A Pathway To Ecosystem Monitoring Using Airborne Environmental Dna, Rachel L. Tulloch, Clare I.M. Adams, Matthew A. Barnes, Elizabeth L. Clare, Henrik C. Van De Ven, Andrew Cridge, Francisco Encinas-Viso, Kristen Fernandes, Dianne M. Gleeson, Erin Hill, Anna J.M. Hopkins, Anna M. Kearns, Gracie C. Kroos, Anna J. Macdonald, Francesco Martoni, Angela Mcgaughran, Todd G.B. Mclay, Linda E. Neaves, Paul Nevill, Andrew Pugh, Kye J. Robinson, Fabian Roger, Tracey V. Steinrucken, Mieke Van Der Heyde, Cecilia Villacorta-Rath, Jenny Vivian

Research outputs 2022 to 2026

Airborne environmental DNA (airborne eDNA) analysis leverages the globally ubiquitous medium of air to deliver broad species distribution data and support ecosystem monitoring across diverse environments. As this emerging technology matures, addressing critical challenges and seizing key opportunities will be essential to fully realize its potentially transformative impact. In June 2024, the Southern eDNA Society convened over 100 researchers, industry leaders, and biodiversity management stakeholders in a landmark workshop to evaluate the current state of airborne eDNA research and chart a course for future development. Participants explored opportunities for integrating airborne eDNA into existing monitoring systems, but they unanimously agreed …


Aiding Depth Perception In Initial Drone Training: Evidence From Camera-Assisted Distance Estimation, John Murray, Steven Richardson, Keith Joiner, Graham Wild Jul 2025

Aiding Depth Perception In Initial Drone Training: Evidence From Camera-Assisted Distance Estimation, John Murray, Steven Richardson, Keith Joiner, Graham Wild

Research outputs 2022 to 2026

Remotely Piloted Aircraft (RPA) pilots frequently experience difficulties with depth perception, particularly when estimating distances between the drone and environmental obstacles. This study evaluates whether the use of onboard camera imagery can improve exocentric distance estimation accuracy among ab initio drone pilots operating under visual line-of-sight (VLOS) conditions. Two groups of undergraduate students performed distance estimation tasks at 20 and 50 m. One group used direct observation only to estimate the exocentric distance between the drone and an obstacle. The second group, as well as direct observation, had access to a live video feed from the drone’s onboard camera via …


Vertical Hydrokinetic Turbine, Miki Harding, Ben E. Mertz Jul 2025

Vertical Hydrokinetic Turbine, Miki Harding, Ben E. Mertz

Rose-Hulman Undergraduate Research Publications

No abstract provided.


Search For Extremely-High-Energy Neutrinos And First Constraints On The Ultrahigh-Energy Cosmic-Ray Proton Fraction With Icecube, Karen Andeen Jul 2025

Search For Extremely-High-Energy Neutrinos And First Constraints On The Ultrahigh-Energy Cosmic-Ray Proton Fraction With Icecube, Karen Andeen

Physics Faculty Research and Publications

We present a search for the diffuse extremely-high-energy neutrino flux using 12.6 years of IceCube data. The nonobservation of neutrinos with energies well above 10 PeV constrains the all-flavor neutrino flux at 1018  eV to a level of 𝐸2⁢Φ𝜈𝑒+𝜈𝜇+𝜈𝜏≃10−8  GeV cm−2 s−1 sr−1, the most stringent limit to date. Using these data, we constrain the proton fraction of ultrahigh-energy cosmic rays (UHECRs) above ≃30  EeV to be  ≲70% (at 90% CL) if the cosmological evolution of the sources is comparable to or stronger than the star formation rate. This is the first result to disfavor the “proton-only” hypothesis for UHECR …


Rattler Python, Samer Jabor Jul 2025

Rattler Python, Samer Jabor

Systems Manuals - 2026

The Rattler Python project is an interactive game-based learning system that intends to teach the basic concepts of Python programming through guided instruction, gameplay challenges, and review-based assessments. The document contains a proposal for this system consisting of problem definition, background research, existing solutions, and the proposed product, together with the system scope, assumptions, and the organization of the remainder of this document.


Garage Sale Web-Based Information System, Sonachi Mogbogu Jul 2025

Garage Sale Web-Based Information System, Sonachi Mogbogu

Systems Manuals - 2026

The Garage Sale web application is in response to a business need of an online interactive system. This system will support the interaction between owners and shoppers of garage sale event. The online information system is a great idea to implement because it will help create sales awareness which will lead to increase in the customer base, and increased sales for event organizers. People are used to the traditional approaches, advertising events through word-of-mouth and posting signs alongside roads, however, having an online information system will be more effective in reaching a wider market of buyers. The traditional approaches do …


Purification Of Uranium Tetrafluoride Using Ammonium Bifluoride, Kyle R. Foster, Juliano Schorne-Pinto, Ronald E. Booth, Annabelle Husek, Mina Aziziha, Hunter B. Tisdale, Bernie W.N. Fitzpatrick, Hans Conrad Zur Loye, Markus H.A. Piro, Theodore M. Besmann Jul 2025

Purification Of Uranium Tetrafluoride Using Ammonium Bifluoride, Kyle R. Foster, Juliano Schorne-Pinto, Ronald E. Booth, Annabelle Husek, Mina Aziziha, Hunter B. Tisdale, Bernie W.N. Fitzpatrick, Hans Conrad Zur Loye, Markus H.A. Piro, Theodore M. Besmann

Faculty Publications

A method of purification for UF4 utilizing NH4HF2 was investigated to remove oxygen and hydrate impurities from the salt. The original salt exhibited a melting point at 915–920 °C, which corresponds to the eutectic temperature of the UF4-UO2 system, showing clear signs of oxygen contamination. To purify the salt, an air-tight reaction vessel inside an argon glovebox was used to react UF4/NH4HF2 mixtures at elevated temperatures under a continuous flow of inert gas. The process yielded a significantly purer UF4 salt as confirmed via inert gas fusion, X-ray diffraction, differential scanning calorimetry and inductively coupled plasma-optical …