Digital Commons Network^™

Comparative Case Studies Of How General Chemistry Ii Students Explain Entropically-Driven Phenomena, Raymundo Aragonez

Open Access Theses & Dissertations

Understanding how students conceptualize entropy remains a central challenge in chemistry education. Often referred to as a "driving force" of chemical reactions, the dispersal of energy as a process proceeds is indicative of a process's spontaneity or thermodynamic favorability. Students frequently default to discussing phenomena in deterministic terms, potentially reflecting the language choice and heuristics selected by the instructor such as "disorder". In this study, assessment prompts about entropy from a convenience sample of general chemistry textbooks were characterized as to their potential to elicit three-dimensional learning, and students' responses to assessment prompts from a curriculum aligned with three-dimensional learning …

Expectations In The Preservation Of Dna And Bacterial Organisms In Differential Montana Burials, Kaylee M. Hinds

Graduate Student Theses, Dissertations, & Professional Papers

This study investigates patterns of decomposition and biomolecular preservation in domestic pig (Sus scrofa domesticus) proxies under varying burial conditions in a cold, seasonal climate. Conducted at the Lubrecht Experimental Forest in western Montana, the project aims to evaluate DNA degradation, microbial activity, and environmental influences across shallow, deep, surface, and secondary burial contexts. Three pigs were placed in distinct burial treatments (surface exposure, partial burial, and full burial), with a fourth site later added following bear disturbance and carcass relocation. Environmental monitoring included temperature, and soil sampling before and throughout the decomposition process. Systematic sampling of bone, soft tissue, …

Designing A Data Collection And Visualization Toolkit For Scalable Tensor Algebra In Quantum Chemistry Applications, Epiya J. Ebiapia

LSU Master's Theses

Large-scale quantum chemistry computations, such as those executed with the Tensor Algebra for Many-body Methods (TAMM) framework, require careful configuration of runtime parameters to achieve high performance and cost efficiency in high-performance computing (HPC) and cloud environments. Without effective performance analysis tools, researchers risk inefficient use of computational resources, leading to longer runtimes and higher costs.

To address this challenge, this thesis presents the design and implementation of a performance profiling and visualization toolkit for TAMM, developed as part of the DOE TEC4 project in collaboration with Pacific Northwest National Laboratory, Microsoft, and Louisiana State University. The toolkit collects detailed …

Insights Into The Radiation Chemistry Of Flash Radiation Therapy, Alan E. Lopez Hernandez

Dissertations and Theses (Open Access)

Purpose: FLASH radiation therapy (FLASH-RT) is an emerging modality that delivers radiation at ultra-high dose rates (UHDR) and has shown consistent normal tissue sparing while preserving tumor control compared to conventional RT—a phenomenon termed the FLASH effect. Despite promising results, the mechanisms behind the FLASH effect remain unclear. Many hypotheses point to radiolytic interactions, but experimental validation is limited. This work aims to develop a robust experimental platform to evaluate the relationship between radiolytic species production and physical beam parameters relevant to FLASH-RT, alongside dosimetry tools for reliable UHDR beam characterization.

Methods: A beam collector (BC) Faraday cup detector was …

Computational Study Of Redox-Active Protein Residues And Biological Proton-Coupled Electron Transfer, Qiwen Zhu

Yale Graduate School of Arts and Sciences Dissertations

Proton-coupled electron transfer (PCET) reactions are essential processes in biological systems, fundamental to various enzymatic functions and redox biology. Key to these reactions are redox-active residues, such as tyrosine and tryptophan, which enhance the efficiency and specificity of electron transfer events. This thesis investigates the thermodynamics, kinetics, and conformational influences of PCET in proteins involving these residues through three projects, each offering significant insights into the mechanisms and broader implications for biological function. The studies have focused on two protein systems: a simple de novo protein system, α3X, and ribonucleotide reductase, an enzyme critical to DNA synthesis. Combining a wide …

Selective Surface Activation And Flotation Of Pyrite For The Recovery Of Tellurium From Sulfide Tailings, Mulenga Mutema Chibesa

Masters Theses

Copper sulfide tailings from past and present mining operations are important secondary sources of critical elements such as tellurium (Te), a key component in cadmium–telluride photovoltaic solar cells. Characterization of tailing streams from copper porphyry (CP) ore flotation revealed that Te-bearing minerals are predominantly hosted in pyrite, which is usually depressed and discarded. Enhancing pyrite recovery is therefore a critical first step toward concentrating Te minerals for downstream extraction. However, pyrite flotation is often hindered by hydrophilic surface complexes formed during prior processing. This research investigated selective flotation of Te-bearing pyrite from CP tailings using micro flotation and bench-scale flotation, …

Demystifying Misconceptions In Introductory Undergraduate Chemistry Education With 3d Printed Molecular Orbitals, Hiwot Endeshaw, Daniel J. O'Leary

Pomona Senior Theses

Spatial abilities are invaluable skills for the science, technology, engineering, and mathematics (STEM) subjects. However, women, people from low socioeconomic backgrounds, and ethnic minorities are more likely to have less developed spatial abilities, which is one of the many contributing factors for the lack of diversity in STEM subjects like chemistry. Teaching spatial skills to undergraduate chemistry students may address this issue and help increase the diversity of students who go on to continue their education in the subject. 3D printing technology in higher education has exploded in recent years, presenting a unique opportunity to teach “hard to grasp” concepts …

Cellular And Behavioral Consequences Of Psychedelic Drug Action In The Claustrum, Tanner L. Anderson

Theses and Dissertations--Neuroscience

Psychedelics are rapidly garnering research attention for their ability to successfully treat a variety of psychiatric diseases after one or a handful of treatments in recent clinical research. Among the conditions treated is substance use disorder (SUD), which afflicted 48.5 million (16.7%) Americans aged 12 and older in 2023 (NSDUH). As clinical trial results continue to show lasting positive effects of psychedelic psychotherapy, there remains an enormous gap in knowledge regarding how these drugs cause lasting changes in the brain to achieve these therapeutic effects. It has been suggested that psychedelics must induce rapid and long-lasting neuronal plasticity in order …

Design And Development Of Fluorescent Probes For Sensing And Bioimaging Of Nad(P)H, Intracellular Viscosity, And So2, Dilka Liyana Arachchige

Dissertations, Master's Theses and Master's Reports

Understanding the dynamic biochemical and biophysical changes within living systems is vital for advancing disease diagnosis and therapeutic development. This work presents the design and development of innovative fluorescent probes, based on cyanine and coumarin scaffolds, for the highly sensitive and selective detection of key metabolic and biophysical markers, NAD(P)H, mitochondrial viscosity, and sulfur dioxide (SO₂) in live cells and fruit fly larvae. A series of cyanine-based probes were engineered to undergo strong fluorescence enhancement upon reduction by NAD(P)H, enabling real-time visualization of metabolic fluctuations in cancer cells and Drosophila larvae. These probes exhibit excellent sensitivity, mitochondrial targeting capability, and …

Multiscale Computational Chemistry Studies Of The Catalytic Mechanisms Of Non-Heme Fe(Ii)/2-Oxoglutarate-Dependent Oxygenases, Simahudeen Bathir Jaber Sathik Rifayee

Dissertations, Master's Theses and Master's Reports

Enzymes catalyze complex biological transformations. Non-heme Fe(II)/2-oxoglutarate (2OG)–dependent enzymes are highly versatile catalysts capable of selective C–H oxidation, enabling transformations such as hydroxylation, halogenation, desaturation, demethylation, ring rearrangements, epoxidation, and electrophilic aromatic substitution. These enzymes are involved in various biological processes, including fatty acid metabolism, hypoxic signaling, collagen maturation, and transcriptional regulation. Computational Modeling provides detailed knowledge of the enzymes including atomistic details of the important catalytic species, conformational and electronic effects, which are crucial to enzyme engineering and drug design efforts. This dissertation implements advanced multi-scale molecular modelling techniques including Molecular dynamics and Quantum Mechanic / Molecular Mechanics calculations …

The Roots Of Empire And Industry: The Transnational History Of The Soviet Rubber Industry, Alexander Hinnov Craver

Graduate Research Theses & Dissertations

Global rubber shortages and market instability in the early 20th century drove the United States, Soviet Union, and Nazi Germany to collaborate in an overwhelming drive to secure domestically producible sources of rubber, either from plants that could grow outside the tropics, or from synthetic rubber processes. The Soviet Union was an indispensable part of this converging, transnational “quest for rubber.” Russian scientists created the first factories to produce synthetic rubber, and Russian agronomists had discovered a dandelion in Central Asia that yielded latex suitable for manufacture. Consequently, both discoveries were disseminated across the world. Sometimes they were shared: the …

Increasing Access Through Graduate Teaching Assistant Training: A Udl-Informed, Video-Based Professional Development Approach For Inclusive Chemistry Instruction, Kathleen Lugo Charriez

Graduate Thesis and Dissertation post-2024

STEM courses pose concealed barriers to learning for students with disabilities, a demographic that constitutes a significant portion of postsecondary science and engineering undergraduate student populations. While extensive research has examined access and inclusiveness in K–12 education and, to a more limited extent, in higher education, there remains a critical gap in understanding how to proactively design undergraduate chemistry curricula that are both accessible and inclusive for a diverse range of learners. In particular, limited attention has been given to supporting Graduate Teaching Assistants (GTAs) in adopting inclusive instructional practices in higher education chemistry courses.

In large academic institutions, GTAs …

Investigating The Photophysical Dynamics Of Anthracene And Acridine Derivatives Using Time-Resolved Spectroscopy, Sophia Tiano

Open Access Dissertations

Anthracenes and acridines are among the simplest visible light absorbing heterocyclic and polycyclic aromatic hydrocarbons and as such are extensively used in a variety of applications including photosensitizers and fluorescent sensors. Although the photophysics of some derivatives have been studied in the past, there is still a lot of unknown fundamental information that is vital in order to optimize these molecules for particular applications. Transient absorption spectroscopy was used to study the photophysics of the 9-substituted methyl, hydroxymethyl and formyl derivatives of acridine and anthracene. The growth and decay of the triplet-triplet absorption peak were quantified for each dye in …

Game-Based Learning With Augmented Reality, Kantida Nanon

Dissertations

Augmented Reality (AR) technology provides an effective and controllable learning environment, especially for complicated, potentially dangerous, or critical content. Effective implementation of interaction and platforms for educational tools can maximize learner engagement and optimize the learning experience. This dissertation explores the potential of AR technology to enhance learning experiences across multiple platforms and subject areas, particularly within chemistry and mathematics. The dissertation is grounded in the field of Human-Computer Interaction (HCI) and explores the potential of AR to increase learner engagement, improve learning outcomes, and transform traditional pedagogical practices.

The dissertation is divided into two parts. The first part examines …

Intrinsic Gas-Phase Behavior Of Uranium Species: A Comprehensive Reactivity Study Of [O=U≡Ch]+ And [Uh]+, Justin Terhorst

Electronic Theses and Dissertations

The intrinsic chemistry of actinide elements, particularly uranium, remains a key challenge in understanding f-block reactivity due to the complexity introduced by solvent interactions, counter-ions, and complex equilibria in the condensed phase. In this dissertation, a systematic gas-phase study utilizing preparative tandem ion-trap mass spectrometry (PTMSⁿ) is presented, focusing on the reactivity of uranium-centered species, specifically [OUCH]⁺, an oxy uranium methylidyne species, and [UH]⁺ ions. By stripping away solvent effects and isolating the ions, PTMSⁿ provides a powerful platform to probe the fundamental chemical behavior of uranium species in their intrinsic state.

The …

Surface Chemistry And Adsorption Mechanism Of Orfom® D8 For Cu Depression In Cu-Mo Flotation, Patrick Jeff Mensah

Graduate Theses & Non-Theses

In traditional chalcopyrite-molybdenite (Cu-Mo) flotation separation systems, inorganic depressants such as NaSH and NaCN are used to selectively depress chalcopyrite making it more hydrophilic so molybdenite can be floated and recovered. NaSH and NaCN are highly toxic, have high explosion potential, strong odor, and readily oxidize in air resulting in a high consumption rates. To control oxidation, nitrogen gas, and Nokes reagent are both necessary, making the process even more expensive. In addressing these challenges, attention is fast shifting to disodium carboxymethyl trithiocarbonate (Orfom® D8), a novel organic depressant designed to replace conventional inorganic depressants because it does not easily …

Investigating Student Expectations, Buy-In, And Engagement In Lower Division Undergraduate Chemistry Labs, Elizabeth Blanche Vaughan

Dissertations and Theses

Laboratory courses constitute an integral aspect of chemistry education at the undergraduate level. Despite their prominence, a growing number of researchers have begun to think more critically about the value of laboratory learning experiences. As pedagogical decisions should be based on evidence, it is necessary for chemistry education researchers and practitioners to investigate the claim that teaching laboratories are a valuable part of science education. Therefore, the aim of this dissertation was to address one small section of this gap in the literature by obtaining a more robust understanding of students' expectations, buy-in, and engagement in lower division, undergraduate, chemistry …

Recruitment Sources Of Grass Carp (Ctenopharyngodon Idella) In The Great Lakes, Nicholas Steven Etter

Theses

Grass Carp (Ctenopharyngodon idella) is a species of concern in areas they have invaded, such the Laurentian Great Lakes, due to their potential to substantially reduce aquatic macrophyte coverage. Efforts to control Grass Carp in the Great Lakes have primarily been focused on two tributaries to the western basin of Lake Erie (i.e., Sandusky and Maumee rivers, Ohio) where reproduction has been documented, although other Great Lakes tributaries are known to have thermal and hydrological regimes suitable for Grass Carp spawning. Knowledge of sources contributing to the expanding population of invasive Grass Carp in the Great Lakes is key to …

Synthesis Of Addressable Libraries: New Lessons And The Need For Proper Characterization For Microelectrode Array-Based Reactions, Albert Huang

Arts & Sciences Graduate Student Theses and Dissertations

The Moeller group has been developing synthetic tools for building molecular libraries on microelectrode arrays since 2004. Such a library is intriguing because one can take advantage of the library for biological signaling studies. Microelectrode arrays can serve as a powerful platform for those experiments since every electrode in the array can be addressed individually. Unique members of the library targeting biological receptors that one is interested in can be restricted only above unique electrodes in an array. Thus, high-affinity ligands for those receptors can be identified with this strategy. To make this method work, one has to make sure …

Using Manipulatives As Learning Interventions To Teach Introductory Chemistry Content In The Secondary Classroom And Beyond, John Kenneth Kennon

Electronic Theses and Dissertations Archive

Use of manipulatives to explore concepts qualitatively and quantitatively was investigated in this study. Particle diagrams, enthalpy, VSEPR, and stoichiometry; four classes of students were divided into two groups constituting test group and control group. Control groups received traditional pedagogy (Lewis diagrams) while test groups used manipulatives. Shapiro-Wilks, class means, Kolmogorov-Smirnov, Mann-Whitney U tests, and item-by-item analyses were employed to quantify performance. Particle diagram results suggested that using modeling improves student learning outcomes based on means and Mann-Whitney U-test p-value. Enthalpy results indicated a larger mean for the test group than the control group, but no statistical difference between score …

Regioselective Hydroamination Of Unactivated Olefins With Diazirine And Total Synthesis Of Nostodione A And Scytonemin, Qingyu Xing

USF Tampa Graduate Theses and Dissertations

As an atom-economic way of carbon-nitrogen bond formation, hydroaminations are great tool for make amines, hydrazines, and other nitrogen-containing heterocycles. Specifically, radical hydroamination is a useful approach for functionalization of unactivated olefins, especially in sterically hindered environments. Diversification remains a challenge for radical hydroaminated products, since the nitrogen sources are carefully designed. In the first chapter of this dissertation, we report a highly diversifiable radical hydroamination reaction with diazirine as a nitrogen source and its potential applications in synthesis of several pharmaceutical interested compounds. Cobalt catalyzed regioselective hydroamination with diazirine shows wide function group tolerance, like phenyl thioether, ketones, esters, …

Protein Residue Analysis In Archaeology: A Geological Contamination Experiment, Theresa Popp

All Graduate Theses and Dissertations, Fall 2023 to Present

Protein residue analysis has been used by archaeologists for decades to explore ancient diets and hunting behaviors based on proteins deposited on tools and artifacts, however, protein contamination of buried artifacts has been assumed but lacked formal study. Through a contamination experiment testing different geological contexts (e.g. water movement and freeze-thaw), possible routes of protein contamination within soil were identified, adversely impacting protein residue analysis conducted on buried artifacts. Protein was found to move through soil in large enough concentrations to elicit positive protein residue results on sterile artifacts that never made direct contact with the protein source used in …

Valorization Of Date Palm Waste For The Isolation, Characterization, And Surface Chemistry Modification Of Nanocellulose, Mohsin Raza

Dissertations

This dissertation focuses on the utilization of date palm waste, a lignocellulosic material, as a source for the extraction of nanocellulose (NC), a versatile biopolymer with applications in biodegradable composites, bioplastics, and food packaging. Conventional methods of NC production using mineral acids such as sulphuric and hydrochloric acid are reaching their limits of toxicity, so more environmentally friendly alternatives such as ionic liquids (ILs) are being explored. The research focuses on the characterization of different date palm wastes to evaluate their α−cellulose content, lignocellulosic character, and thermal stability. By comparing extraction methods with mineral acids and ILs, the study evaluates …

Drip Water Chemistry Response To Human Activities At Diamond Caverns In Park City, Kentucky, Madison R. High

Honors Theses

This research aims to give insight into factors contributing to seasonal variation of karst cave drip water hydrochemistry relative to surface condition. The study area is a small show cave, Diamond Caverns, located just outside the boundary of Mammoth Cave National Park in Kentucky. Various water chemistry parameters, such as chloride, pH, and temperature were monitored. A YSI EXO2 was deployed to measure the aforementioned parameters at one-hour intervals in a drip water pool starting in November 2023. To discern significant changes in solute concentrations, daily averages were calculated based on the hourly data. Daily averages were then compared to …

Unusual Eluents, Small Systems, And Digital Signal Processing For Highly Efficient Greener Separations, Troy T. Handlovic

Chemistry & Biochemistry Dissertations - Archive

Separation science is a rapidly evolving field, where routine analyses are now done at speeds and efficiencies not thought to be possible several years ago. The tangential field of green analytical chemistry is evolving at an even faster rate and can be considered to be in its infancy stage. As green analytical chemistry is better understood, the greenness of a method will be considered during standard method development just as resolution, sensitivity, and efficiency are considered now. The first portion of this dissertation focuses on the development of mathematical and pragmatic methods to minimize the analytical method greenness score, and …

Combined In Silico And Experimental Approaches Of Pharmacognosy To Resolve Complex Natural Product Issues, William Michael Neal

Electronic Theses and Dissertations

Since the identification of useful bioactive natural products can often involve tedious dereplication measures to decipher complex mixtures, much emphasis is placed on methods that can effectively characterize natural products. Several in silico methods, such as quantitative structure-activity relationships (QSARs), molecular docking, and quantum calculations, provide researchers with valuable tools to overcome the challenge of complex natural product mixtures. To exemplify the abilities of computational methodologies to further the field of pharmacognosy, this dissertation elaborates on several research projects involving computational approaches in pharmacognosy, including: (1) global assessment of pregnane X receptor (PXR) agonism via multiple QSAR models, (2) differentiation …

A Phytochemical Analysis Of Secondary Metabolites In Eupatorium Serotinum, Elise Snow

Theses and Dissertations

Phytochemistry, a subset of Natural Products Chemistry, studies chemically derived products from natural substances. Advances in this field have important applications in medicinal research due to the distinctive and unique properties of natural compounds. All metabolites are produced from the metabolic cycle, which is a pathway that provides energy for the organism. These metabolic compounds vary greatly and are classified based on their function within the organism. Primary metabolites are abundant and contribute to organism growth, development, and maintenance of energy. Secondary metabolites are found in lesser quantity and correlate to natural defense mechanisms. For example, salicylic acid is a …

“Increasing Renewable Energy Potential Of Landfill Gas By Electrocatalytic Conversion Of Carbon Dioxide To Methane At Low Temperature.”, Asma Akter Rony

Civil Engineering Dissertations - Archive

The conversion of carbon dioxide into methane at a low temperature has great potential to reduce current international environmental issues like global warming and will create new sources of renewable energy. The overall goal of this research is to increase renewable energy production from landfill gas using an unconventional process – electrocatalytic methanation of carbon dioxide – which has not been implemented for landfill gas yet. The electrocatalytic methanation follows the Waseda process, which applies an electric field in the presence of a Ruthenium-supported cerium oxide (CeO2) catalyst. The specific objectives of this research were: 1. To explore the impact …

Computational Quantum Chemistry Studies Of The Stabilities Of Radical Adducts Formed During The Oxidation Of Melatonin Derivatives, James Horne

Electronic Theses and Dissertations

Melatonin is a natural antioxidant that has been investigated for properties as a potential spin trap to identify short-lived free radicals. Computational quantum chemistry studies have been performed for the oxidation of melatonin to N¹-acetyl-N²-formyl-5-methoxykynuramine. This research focused on modification of melatonin into derivatives and analyzing the change in total molecular energy from melatonin to its oxidation product, as well as the corresponding derivatives. Each of the molecular geometries were optimized at the DFT/B3LYP/6-31G(d), DFT/B3LYP/cc-pVXZ (X = D, T), HF/6-31G(d), HF/cc-PVXZ (X = D, T), MP2/6-31G(d), and MP2/cc-PVXZ (X = D, T) levels of theory. …

Cognitive Engagement During Group Learning Activities In Chemistry Courses: An Analysis Of Student Discourse, Safaa Youssef El-Mansy

Dissertations and Theses

As educators, our goal is to help our students be successful, but in order to accomplish this, we need to understand what factors contribute to student success. One factor, small-group active learning, has been correlated to improved academic outcomes; however, the magnitude of this improvement can vary across different courses, different types of group work, and even across courses that use the same group work structure. Therefore, it is important to understand what aspects of group work contribute to its effectiveness. The work presented in this dissertation investigated one specific aspect: students’ cognitive engagement. This was done by analyzing the …