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Articles 31 - 60 of 2906

Full-Text Articles in Physical Sciences and Mathematics

Probing The Surface Structure Of Ferrocene Modified Electrodes Using Cyclic Voltammetry, Rebekah S. Stanley May 2024

Probing The Surface Structure Of Ferrocene Modified Electrodes Using Cyclic Voltammetry, Rebekah S. Stanley

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

Modifying electrodes imparts new electrochemical properties for use in various applications. To fully understand these electrochemical properties the structure of the modified surface needs to be characterized. Cyclic voltammetry (CV) offers a quick and simple way to determine if the surface structure has been homogeneously modified even at low surface concentrations. Nonideal responses in CV scans give insights to the microenvironments and structure of the monolayer surface that may be indistinguishable in other techniques. Peak fitting CV data, coupled with other surface techniques, can further characterize the contributions and nature of these microenvironments and aid in structural determination.


An Overview Of How To Measure The Kinetic Properties Of An Anode Material For The Chlorine Evolution Reaction, Cameron Vann May 2024

An Overview Of How To Measure The Kinetic Properties Of An Anode Material For The Chlorine Evolution Reaction, Cameron Vann

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

The process of generating chlorine gas using electrolysis in aqueous systems is well established. However, a new process requires chlorine to be generated at high temperatures using molten salt. This harsh environment requires a new study of anode materials for the chlorine evolution reaction. Anode materials can be compared by their kinetic parameters, the transfer coefficient α and the exchange current i0. The basic theory of these properties as they relate to the chlorine evolution reaction has been detailed and an analysis method for finding these effective parameters has been shown and demonstrated.


Model To Demonstrate Effects Of Mass Transfer And Applied Current In An Electrolytic Cell, George Ankrah May 2024

Model To Demonstrate Effects Of Mass Transfer And Applied Current In An Electrolytic Cell, George Ankrah

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

This study investigates the relationship between applied current and resulting cell potential in an electrolytic system, considering the transport of electroactive species. By applying Michael Faraday's laws of electrolysis and the Nernst-Planck equation, the behavior of electroactive species in diffusion-controlled systems with and without stirring is modeled. The plots demonstrate how stirring enhances ion transport and establishes a stable Nernst diffusion layer, affecting the kinetics of electrochemical reactions. Understanding these dynamics is crucial for optimizing electrolysis processes.


Model Of The Effect Of Voltage On Contact Angle In An Electrolytic Cell Reaction, Aaron Essilfie May 2024

Model Of The Effect Of Voltage On Contact Angle In An Electrolytic Cell Reaction, Aaron Essilfie

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

This paper investigates the hypothesis that the contact angle at the meniscus of an electrode-electrolyte can be altered during a redox reaction through the coupled understanding of electrowetting and capillarity rise. Recent studies in electrowetting have focused on dielectric surfaces but research on contact angle at the electrode-electrolyte surface is lacking. The study employs a basic electrolytic cell. By applying principles of electrowetting and capillary rise the research aims to understand the relationship between applied voltage and contact angle, to advancements in electrochemistry and microfluidics.


Review Of Cyclic Voltammetry Measurements For Uranium In Flinak Molten Salt, Jackson Ivory May 2024

Review Of Cyclic Voltammetry Measurements For Uranium In Flinak Molten Salt, Jackson Ivory

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

The electrochemical behavior of uranium FLiNaK molten salts is explored, focusing on cyclic voltammetry (CV) as a powerful tool for redox characterization and diffusion studies. Through a comprehensive review of recent research, the study highlights the significance of CV in understanding electrode kinetics, material compatibility, and process optimization in molten salt environments. The findings underscore the potential of FLiNaK molten salt reactors in advancing nuclear energy technologies, fuel processing, and waste management strategies. Collaborative interdisciplinary efforts are emphasized to address challenges and accelerate innovation in electrochemical methods for nuclear applications.


Dissecting Trypanosome Metabolism By Discovering Glycolytic Inhibitors, Drug Targets, And Glycosomal Ph Regulation, Daniel Hale Call May 2024

Dissecting Trypanosome Metabolism By Discovering Glycolytic Inhibitors, Drug Targets, And Glycosomal Ph Regulation, Daniel Hale Call

Theses and Dissertations

Trypanosoma brucei, the causative agent of African trypanosomiasis, and its relatives Trypanosoma cruzi and several Leishmania species belong to a class of protozoa called kinetoplastids that cause a significant health burden in tropical and semitropical countries across the world. While an improved therapy was recently approved for African trypanosomiasis, the therapies available to treat infections caused by T. cruzi and Leishmania spp. remain relatively poor. Improving our understanding of T. brucei metabolism can inform on metabolism of its relatives. The purpose of the research presented in this dissertation was to develop novel tools and methods to study metabolism in T. …


An Investigation Of The Interactions Of Gradient Coherence And Network Pruning In Neural Networks, Zachary Yauney Apr 2024

An Investigation Of The Interactions Of Gradient Coherence And Network Pruning In Neural Networks, Zachary Yauney

Theses and Dissertations

We investigate the coherent gradient hypothesis and show that the coherence measurements are different on real and random data regardless of the network's initialization. We introduce "diffs," an attempt at an element-wise approximation at coherence, and investigate their properties. We study how coherence is affected by increasing the width of simple fully-connected networks. We then prune those fully-connected networks and find that sparse networks outperform dense networks with the same number of nonzero parameters. In addition, we show that it is possible to increase the performance of a sparse network by scaling the size of the dense parent network it …


Trip - Transformer Interatomic Potential Predicts Realistic Energy Surface Using Physical Bias, Bryce Eric Hedelius Apr 2024

Trip - Transformer Interatomic Potential Predicts Realistic Energy Surface Using Physical Bias, Bryce Eric Hedelius

Theses and Dissertations

Accurate interatomic energies and forces enable high-quality molecular dynamics simulations, torsion scans, potential energy surface mapping, and geometry optimization. Machine learning algorithms have enabled rapid estimates of energies and forces with high accuracy. Further development of machine learning algorithms holds promise for producing general potentials that support dozens of atomic species. I present my own Transformer Interatomic Potential (TrIP): a chemically sound potential based on the SE(3)-Transformer. TrIP's species-agnostic architecture--using continuous atomic representation and homogenous graph convolutions--encourages parameter sharing between atomic species for more general representations of chemical environments, keeps a reasonable number of parameters, serves as a form of …


Head Tail Open: Open Tailed Classification Of Imbalanced Document Data, Chetan Joshi Apr 2024

Head Tail Open: Open Tailed Classification Of Imbalanced Document Data, Chetan Joshi

Theses and Dissertations

Deep learning models for scanned document image classification and form understand- ing have made significant progress in the last few years. High accuracy can be achieved by a model with the help of copious amounts of labelled training data for closed-world classification. However, very little work has been done in the domain of fine-grained and head-tailed(class imbalance with some classes having high numbers of data points and some having a low number of data points) open-world classification for documents. Our proposed method achieves a better classification results than the baseline of the head-tail-novel/open dataset. Our techniques include separating the head-tail …


Unique K3 Surfaces With Purely Non-Symplectic Automorphism: Insights From Weighted Projective Spaceunique K3 Surfaces With Purely Non-Symplectic Automorphism:\\Insights From Weighted Projective Space, Elizabeth Melville Apr 2024

Unique K3 Surfaces With Purely Non-Symplectic Automorphism: Insights From Weighted Projective Spaceunique K3 Surfaces With Purely Non-Symplectic Automorphism:\\Insights From Weighted Projective Space, Elizabeth Melville

Theses and Dissertations

K3 surfaces have garnered attention across various fields, from optics and dynamics to high energy physics, making them a subject of extensive study for many decades. Recent work by mathematicians, including Brandhorst [1], has focused on non-symplectic automorphisms, aiming to categorize K3 surfaces that admit such automorphisms. Brandhorst made a list of unique K3 surfaces with purely non-symplectic automorphisms and established specific criteria for a K3 surface to be isomorphic to one on his list. This thesis aims to provide an alternative representation of select K3 surfaces from Brandhorst's list. While Brandhorst predominantly characterizes these surfaces as elliptic K3 surfaces, …


The Generation Of Terahertz Light And Its Applications In The Study Of Vibrational Motion, Aldair Alejandro Apr 2024

The Generation Of Terahertz Light And Its Applications In The Study Of Vibrational Motion, Aldair Alejandro

Theses and Dissertations

Terahertz (THz) spectroscopy is a powerful tool that uses ultrashort pulses of light to study the properties of materials on picosecond time scales. THz light can be generated through a variety of methods. In our lab, we generate THz through the process of optical rectification in nonlinear optical (NLO) organic crystals. THz light can be used to study several phenomena in materials, such as spin precession, electron acceleration, vibrational and rotational motion. The work presented in this dissertation is divided into two parts: (1) the generation of THz light and (2) applications of THz light. The first portion of this …


Multifunctional And Moisture Tolerant Zinc-Based Mono- And Bi-Metallic Metal-Organic Framework (Mof) Thin Films, Emmanuel Agbata Apr 2024

Multifunctional And Moisture Tolerant Zinc-Based Mono- And Bi-Metallic Metal-Organic Framework (Mof) Thin Films, Emmanuel Agbata

Theses and Dissertations

Many applications of metal-organic frameworks (MOFs) are highly dependent on their structures. The type and consistency of structure inform their properties. Zinc-based MOFs are applicable in different fields because of the low toxicity of zinc materials and are therefore also useful for catalysis. While MOF-5, a zinc-based MOF with carboxylate linkers is moisture intolerant, a variant of this is moisture tolerant. The introduction of a nitrogen-based linker in the zinc MOF which renders the structure moisture-tolerant. This material has not been explored as much, despite its multifunctional properties. Furthermore, the growth of Zn-based bimetallics of this MOF has not yet …


Applying Mathematical Modeling To The Study Of Family Systems, Dahlia Maxwell Apr 2024

Applying Mathematical Modeling To The Study Of Family Systems, Dahlia Maxwell

Theses and Dissertations

Mathematical modeling provides a powerful framework for insight into current scientific theories as well as hypothesis generation for further research. Despite its undeniable potential to enrich scientific advancement, the application of mathematical modeling remains conspicuously scarce in the field of family science. The complexity inherent in family dynamics, coupled with the intricate interplay of emotions in the individual, underscores the necessity of a robust analytical approach. Addressing this critical gap in the literature, this thesis introduces a sophisticated mathematical model of family dynamics integrating essential elements from family systems theory, emotion dynamics, and appraisal theory. The model is implemented as …


Advancing Single-Cell Proteomics Through Innovations In Liquid Chromatography And Mass Spectrometry, Kei Grant Isaac Webber Apr 2024

Advancing Single-Cell Proteomics Through Innovations In Liquid Chromatography And Mass Spectrometry, Kei Grant Isaac Webber

Theses and Dissertations

Traditional proteomics studies can measure many protein biomarkers simultaneously from a single patient-derived sample, promising the possibility of syndromic diagnoses of multiple diseases sharing common symptoms. However, precious cellular-level information is lost in conventional bulk-scale studies that measure tissues comprising many types of cells. As single cells are the building blocks of organisms and are easier to biopsy than traditional bulk samples, performing proteomics on a single-cell level would benefit clinicians and patients. Single-cell proteomics, combined with mass spectrometry imaging, can be used to analyze cells in their microenvironment, preserving spatial information. We have previously used laser-capture microdissection to isolate …


Robot Proficiency Self-Assessment Using Assumption-Alignment Tracking, Xuan Cao Apr 2024

Robot Proficiency Self-Assessment Using Assumption-Alignment Tracking, Xuan Cao

Theses and Dissertations

A robot is proficient if its performance for its task(s) satisfies a specific standard. While the design of autonomous robots often emphasizes such proficiency, another important attribute of autonomous robot systems is their ability to evaluate their own proficiency. A robot should be able to conduct proficiency self-assessment (PSA), i.e. assess how well it can perform a task before, during, and after it has attempted the task. We propose the assumption-alignment tracking (AAT) method, which provides time-indexed assessments of the veracity of robot generators' assumptions, for designing autonomous robots that can effectively evaluate their own performance. AAT can be considered …


Reproduce Or Live Longer?: A Life History Analysis Of Black Bears In A Semiarid Environment, Brenden M. Orocu, Cambria Armstrong, Janene Auger, Hal L. Black, Randy T. Larsen, Brock R. Mcmillan, Mark C. Belk Mar 2024

Reproduce Or Live Longer?: A Life History Analysis Of Black Bears In A Semiarid Environment, Brenden M. Orocu, Cambria Armstrong, Janene Auger, Hal L. Black, Randy T. Larsen, Brock R. Mcmillan, Mark C. Belk

Library/Life Sciences Undergraduate Poster Competition 2024

In population demographics, each population has an age stage vital rate (fecundity and survival) in its life history that has the greatest influence on the asymptotic population growth rate, λ.

American black bears (Ursus americanus) are found throughout North America. Other studies on population demographics have focused on populations in higher resource availability areas but none in semiarid environments where resource scarcity is a result of the variable climate.

Objective

Our objective was to determine if factors influencing population dynamics of black bears in semi-arid environments were similar to factors affecting population dynamics in mesic environments where …


Cell Motion And Multicellular Organization: A Mathematical Model For Pattern Formation In The Dictyostelium Discoideum Slug, Henry Tullis, Emily Evans, John Dallon Mar 2024

Cell Motion And Multicellular Organization: A Mathematical Model For Pattern Formation In The Dictyostelium Discoideum Slug, Henry Tullis, Emily Evans, John Dallon

Library/Life Sciences Undergraduate Poster Competition 2024

Understanding multicellular behavior is key to biology and medicine

  • Embryonic development requires coordinated cell motion, differentiation
  • Wound healing also relies on emergent multicellular processes
  • Dictyostelium discoideum (Dd) has been identified as a model organism for biomedical research, partly because it is a simple example of multicellularity
  • Understanding Dd can improve, inform approaches to these tricky problems


Cold And Traffic Tolerance Of Hybrid Bermudagrass And Kentucky Bluegrass In A Cool Season, Arid Climate, Caden J. Seely, H. Burgin, N. Hansen, G. Wear, Bryan G. Hopkins Mar 2024

Cold And Traffic Tolerance Of Hybrid Bermudagrass And Kentucky Bluegrass In A Cool Season, Arid Climate, Caden J. Seely, H. Burgin, N. Hansen, G. Wear, Bryan G. Hopkins

Library/Life Sciences Undergraduate Poster Competition 2024

  • Due to climate change, warm-season Hybrid Bermudagrass (HBG) is beginning to be grown in northern climates.
  • This is potentially desirable because it may use less water than traditional species.
  • However, there is concern regarding winter kill and excessively long dormant periods.
  • There is particular interest in HBG with regards to sports turf, but there is concern with its ability to withstand heavy traffic damage when grown in a cool-season climate.

Objective: Assess the cold and traffic tolerance of common Bermudagrass [CBG; Cynodon dactylon (L) Pers.] and seven triploid interspecific hybrids (HBG; Cynodon dactylon × C. transvaalensis Burtt Davy) in …


The Biomechanics Of Ursine Predation: Investigating The Force Generation And Mechanical Properties Of Bear Claws And Teeth In Predatory Behavior, Katie Dooley, Megan Doxey, Josh Jewell, Tom Smith Mar 2024

The Biomechanics Of Ursine Predation: Investigating The Force Generation And Mechanical Properties Of Bear Claws And Teeth In Predatory Behavior, Katie Dooley, Megan Doxey, Josh Jewell, Tom Smith

Library/Life Sciences Undergraduate Poster Competition 2024

  • Studied over 2,200 human-bear conflicts in North America and witnessed the shear force that bears can exert to access food and eliminate any threats.
  • Polar bears at the Hogle Zoo in Salt Lake City punctured and bent high density polyurethane (HDPE) objects when playing with them.
  • This prompted research into the force it takes bears to puncture objects with their canines and claws.


N-H Nhc Palladium Catalysts Derived From Unique 2-Phosphinoimidazole Precursors For C-C Cross Coupling Reactions And Application Of Slow Releasing Polymers Impregnated With Gibberellic Acid To Overcome Seed Dormancy For Land Reclamation, Alexandra Jean Setelin Larson Mar 2024

N-H Nhc Palladium Catalysts Derived From Unique 2-Phosphinoimidazole Precursors For C-C Cross Coupling Reactions And Application Of Slow Releasing Polymers Impregnated With Gibberellic Acid To Overcome Seed Dormancy For Land Reclamation, Alexandra Jean Setelin Larson

Theses and Dissertations

Organometallic chemistry is highly dependent upon the ligands which are employed on a metal's surface. These ligands control steric bulk and electronics of the metal center which can change the reactivity of the organometallic complex. Ligands that are standard in organometallic chemistry include phosphine ligands. These phosphine ligands have been utilized in the field since the 1960's and have shaped the development of many key organometallic catalysts. Phosphine ligands are easily functionalized and highly reactive. This increased reactivity, however, causes severe limitations as phosphine ligands are often unstable under standard benchtop conditions and must be handled both air and moisture …


Gt-Ches And Dycon: Improved Classification For Human Evolutionary Systems, Joseph S. Johnson Mar 2024

Gt-Ches And Dycon: Improved Classification For Human Evolutionary Systems, Joseph S. Johnson

Theses and Dissertations

The purpose of this work is to rethink the process of learning in human evolutionary systems. We take a sober look at how game theory, network theory, and chaos theory pertain specifically to the modeling, data, and training components of generalization in human systems. The value of our research is three-fold. First, our work is a direct approach to align machine learning generalization with core behavioral theories. We made our best effort to directly reconcile the axioms of these heretofore incompatible disciplines -- rather than moving from AI/ML towards the behavioral theories while building exclusively on AI/ML intuition. Second, this …


Development Of Bifunctional Peptides As Scaffolds For Bifunctional Catalysis And A Novel Method Of Peptide Stapling Using Squaric Esters, Adam X. Wayment Mar 2024

Development Of Bifunctional Peptides As Scaffolds For Bifunctional Catalysis And A Novel Method Of Peptide Stapling Using Squaric Esters, Adam X. Wayment

Theses and Dissertations

Enzymes are some of nature's most powerful tools in chemical processes. However, their molecular complexity makes them difficult to synthesize and complicates their application in traditional organic synthesis. Peptides, a building block of enzymes, can be rapidly synthesized and have been used as a possible alternative in achieving enzyme-like catalysis. However, most peptide-based catalysts are limited in reaction-scope and are unable to incorporate traditional organic catalysts. We have designed a helical peptide scaffold capable of being functionalized with a wide variety of organocatalysts as well as transition-metal based catalysts. In order to understand how the peptide structure effects reactivity and …


Raw Nmr Data For Tripeptides, David J. Michaelis, Scott R. Burt, Mariur Rodriguez Moreno, Nye C. Johnson, Christopher B. Stewart, Mary L. Setelin, Adam X. Wayment, Braxton M. Felix Feb 2024

Raw Nmr Data For Tripeptides, David J. Michaelis, Scott R. Burt, Mariur Rodriguez Moreno, Nye C. Johnson, Christopher B. Stewart, Mary L. Setelin, Adam X. Wayment, Braxton M. Felix

ScholarsArchive Data

This data set contains primary data for 50 tripeptides that were generated as part of an advanced undergraduate laboratory experience in solid phase peptide synthesis. The raw data can be processed sing NMR interpretation software and can be used as problems for exams and quizzes or as supplementary materials for a laboratory experience


Historical Analysis Of Urban Dust Generated By The Great Salt Lake Playa, Callum Flowerday, Jaron C. Hansen, Rebekah Stanley, Kaitlyn Brewster Feb 2024

Historical Analysis Of Urban Dust Generated By The Great Salt Lake Playa, Callum Flowerday, Jaron C. Hansen, Rebekah Stanley, Kaitlyn Brewster

ScholarsArchive Data

Historical PM10 filters, provided by the Utah Division of Air Quality, were analyzed for elemental composition of various metals. This was done using ICP-MS.

Also included, EPA PM10 historical data and bathymetry data provided by the Utah USGS.


Historical Ozone Isopleths For Salt Lake Valley, Ut, Usa, Callum Flowerday, Isaac Sudweeks, Brad Adams, Jaron C. Hansen Feb 2024

Historical Ozone Isopleths For Salt Lake Valley, Ut, Usa, Callum Flowerday, Isaac Sudweeks, Brad Adams, Jaron C. Hansen

ScholarsArchive Data

EPA quality assured data, collected by the Utah Division of Air Quality, was used for this analysis.


New Mathematics Teachers' Goals, Orientations, And Resources That Influence Implementation Of Principles Learned In Brigham Young University's Teacher Preparation Program, Caroline S. Gneiting Feb 2024

New Mathematics Teachers' Goals, Orientations, And Resources That Influence Implementation Of Principles Learned In Brigham Young University's Teacher Preparation Program, Caroline S. Gneiting

Theses and Dissertations

Research in mathematics education shows that new mathematics teachers struggle to implement reform teaching practices that they learned in their teacher preparation programs. In this study, the researcher observed and interviewed three new mathematics teachers (within five years of graduation) to further explore the question of why new teachers use or do not use what they learned in their teacher preparation program. The study uses an expanded version of Schoenfeld's decision-making theory of Orientations, Goals, and Resources. This theory proved useful in the analysis of the research data, providing a framework to incorporate and organize the numerous reasons suggested by …


Usability-Driven Security Enhancements In Person-To-Person Communication, Tarun Kumar Yadav Feb 2024

Usability-Driven Security Enhancements In Person-To-Person Communication, Tarun Kumar Yadav

Theses and Dissertations

In the contemporary digital landscape, ensuring secure communication amid widespread data exchange is imperative. This dissertation focuses on enhancing the security and privacy of end-to-end encryption (E2EE) applications while maintaining or improving usability. The dissertation first investigates and proposes improvements in two areas of existing E2EE applications: countering man-in-the-middle and impersonation attacks through automated key verification and studying user perceptions of cryptographic deniability. Insights from privacy-conscious users reveal concerns about the lack of E2EE support, app siloing, and data accessibility by client apps. To address these issues, we propose an innovative user-controlled encryption system, enabling encryption before data reaches the …


Open System Neural Networks, Bradley Hatch Jan 2024

Open System Neural Networks, Bradley Hatch

Theses and Dissertations

Recent advances in self-supervised learning have made it possible to reuse information-rich models that have been generally pre-trained on massive amounts of data for other downstream tasks. But the pre-training process can be drastically different from the fine-tuning training process, which can lead to inefficient learning. We address this disconnect in training dynamics by structuring the learning process like an open system in thermodynamics. Open systems can achieve a steady state when low-entropy inputs are converted to high-entropy outputs. We modify the the model and the learning process to mimic this behavior, and attend more to elements of the input …


Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia Dec 2023

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …


Understanding The Origin, Evolution, And Dynamics Of Transneptunian Binaries, Benjamin C N Proudfoot Dec 2023

Understanding The Origin, Evolution, And Dynamics Of Transneptunian Binaries, Benjamin C N Proudfoot

Theses and Dissertations

This dissertation discusses research that focuses on understanding transneptunian objects (TNOs) using a variety of techniques and approaches. In Chapter 1, I introduce the main concepts used throughout this dissertation and discuss the current understanding of the transneptunian region. In Chapter 2, I discuss my efforts to understand how Neptune's late stages of migration affect the Haumea family, the only known collisional family in the transneptunian region. Using advanced simulations of Neptune migration, I find that the Haumea family can plausibly form before the termination of giant planet migration and show that this extensively mixes the family. The simplest explanation …