Digital Commons Network^™

Norman H. Cromwell, Unl Chemistry; Nu System Dean; Eppley Cancer Center Director, Norman H. Cromwell, Pete Boughn, Mark A. Griep

UNL ORCA Interview Series

This 1980 interview of Normal Cromwell was done by Pete Boughn at the University of Nebraska Medical Center in Omaha. He asked about Cromwell’s history but mostly about his time as director of the Eppley Cancer Center. The interview is reproduced with permission from the UNMC McGoogan Library.

Cromwell was born in 1913 in Terre Haute, Indiana. In 1935, he earned a bachelor’s degree in chemical engineering from the Rose-Hulman Institute of Technology in his hometown. In 1939, three things happened: he earned a doctorate in organic chemistry from the University of Minnesota, he got married, and he was hired …

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 …

Long-Term Variability Of Air Quality And Greenhouse Gas Emissions From Rice Crop Burning In Punjab During 2012–2020, Harsimranjit Kaur Romana, Dericks Praise Shukla, Ramesh P. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Punjab, India's primary rice and wheat production hub, has witnessed rapid expansion of paddy cultivation over the past two decades, driven by minimum support price incentives, changes in government policies, alignment of sowing with the monsoon season and the adoption of high-yielding varieties. This transition has intensified groundwater extraction and shortened the fallow period between rabi and kharif crop seasons, reducing the window between rice harvesting and wheat sowing, leading to widespread open-field burning of rice residue and recurrent post-monsoon air-quality deterioration across the Indo-Gangetic Plain. Despite numerous short-term or single-pollutant assessments, a spatially resolved, multi-pollutant and multi-decadal evaluation linking …

Effects Of Varying Ph, Temperature, And Sucrose Concentration On The Activity Of Invertase Enzyme, B. Rainwater, S. Pratihar

Journal of the Arkansas Academy of Science

The purpose of this research is to study the factors that affect the enzymatic activity of invertase, extracted from baker’s yeast, on hydrolysis of sucrose in aqueous medium. Invertase, a glycoprotein, is an enzyme in the glycoside hydrolase family. It catalyzes the hydrolysis of sucrose producing equimolar mixture of a-D-glucose and b-D-fructose. Invertase shows high affinity for the substrate, and is capable of both cleaving the glycosidic linkage in sucrose and transferring ab-D-O-fructofuranoside residue to an acceptor substrate. (Toledo et al. 2019). A detailed mechanism of the action of invertase was postulated by Shall et al. (Shall et al. 1971). …

Simulating Chemiluminescence Spectra Of Oh Radical Using Quantum Dynamical Simulations, Triet M. Cao

Research from the Berry Summer Thesis Institute, 2025

Chemiluminescence is a phenomenon of light emission that occurs when molecules transition from an excited state to the ground state. This phenomenon is widely utilized in applications ranging from quantifying product yields in chemical reactions to biological imaging and atmospheric chemistry studies. It has also been used in many crucial applications in the scarce conditions of heat and electricity, such as light sources for astronomy discovery or deep-sea diving. A notable example of such reactions is combustion, where highly reactive hydroxyl radicals (OH) are products. These radicals exhibit a chemiluminescence spectrum because of the interaction between their ground state and …

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 …

Vacuum Consistent Electrochemistry In Ionic Liquid Combined With Oxide Epitaxy, Yuji Matsumoto

Journal of Electrochemistry

We introduce our state-of-the art of “vacuum consistent electrochemistry” to an investigation of the interfaces between oxides and ionic liquid (IL). Pulsed laser deposition (PLD) has been one of the powerful and sophisticated techniques to realize nanoscale preparation of high-quality epitaxial oxide thin films. On the other hand, electrochemistry is a simple, very sensitive, and non-destructive analysis technique for solid-liquid interfaces. To ensure the reproducibility in experiment of the interfaces of such epitaxial oxide films, as well as bulk oxide single-crystals, with IL, we employ a home-built PLD-electrochemical (EC) system with IL as an electrolyte. The system allows one to …

Next-Generation Biomedical Implants And Stimuli Responsive Soft Optical Arrays Via Surface Functionalized Elastomeric Materials, John M. Kapitan

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

The demands of emerging technologies, such as soft robotics, stretchable electronics, and next generation biomedical implants, has led to the development of diverse polymeric and hybrid organic/inorganic materials specifically tuned to meet these challenges. These materials typically have low Young’s moduli and are inert with high chemical stability. However, this has led to materials that are static in nature, lacking any meaningful way of responding to changes in their environment and adapting to these changes. This has driven a shift towards the design, manufacturing, and characterization of various stimuli responsive surfaces, relying on precise control of surface chemical coatings and …

Postseismic Groundwater Quality Investigation In Aquifers Following Earthquake-Induced Demolition Wastes: Hatay (Türkiye) Case Study, Pinar Avci, Gali̇p Yüce

Turkish Journal of Earth Sciences

The February 6, 2023 seismic sequence that hit, the Antakya district of Hatay (Türkiye), killed more than 50,000 people and caused extensive structural damages, resulting in the collapse of 80% of the building stock that generated over 100 million tons of debris. Understanding the impact of seismic events on water resources is highly important for ensuring human and environmental health. Herewith, a study was carried out over the Hatay area to assess the post-earthquake sustainable usability of groundwater for drinking, domestic, and irrigation purposes. 17 water points were investigated in September 2023, encompassing alluvial deposits with relatively high hydraulic conductivity …

Stephen J. Lippard: Chemistry Meets Medicine, Radwa Elrouby

Natural Sciences Student Research Presentations

Key Study

In "DNA Sequence Context Modulates the Impact of a Cisplatin 1,2-GpG Intrastrand Cross-Link", Pilch, Todd, and Lippard found that the DNA sequence around the binding site influences how tightly cisplatin binds (Pilch, Todd, and Lippard).

Biophysical techniques like melting temperature and circular dichroism showed that some sequences stabilize DNA more strongly after drug binding (Pilch, Todd, and Lippard).

This explains why cisplatin is more effective in some tumor genomes (Todd and Lippard).

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 …

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 …

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 …

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 …

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 …

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 …

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, …

Using Flipped Classroom Modules To Facilitate Higher Order Learning In Undergraduate Organic Chemistry, Lauren R. Holloway, Tabitha Miller, Bryce Da Camara, Paul M. Bogie, Briana L. Hickey, Jack Barbera, Angie L. Lopez, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

In an ongoing effort to incorporate active learning and promote higher order learning outcomes in undergraduate organic chemistry, a hybrid (“flipped”) classroom structure has been used to facilitate a series of collaborative activities in the first two courses of the lower division organic chemistry sequence. An observational study of seven classes over a five-year period reveals there is a strong correlation between performance on the in-class activities and performance on the final exam across all classes; however, a significant number of students in these courses continue to struggle on both the in-class activities and final exam. The Activity Engagement Survey …

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 …

Efficacy Of Gonacon Fertility Control Against Prairie Dogs And Potential For Uses On Other Rodent Species, Aaron B. Shiels, Emily W. Ruell, Jason E. Bruemmer

United States Department of Agriculture Wildlife Services: Staff Publications

Use of a contraceptive (i.e., fertility control) is attractive for rodent management where lethal control is unwanted. Although population reduction is generally unachievable with small-scale, short-term contraceptive use, reduced juvenile recruitment is achievable. The injectable immunocontraceptive vaccine GonaCon (active ingredient: gonadotropin releasing hormone [GnRH]) was registered in 2022 by the United States Environmental Protection Agency (EPA) for controlling fertility of female prairie dogs (Cynomys, a type of ground squirrel) in urban/suburban settings. Here we: 1) describe past research, including a replicated field study in Colorado (GonaCon treatment vs. control sites) testing efficacy of GonaCon in prairie dogs, which …

Adsorption Behavior And Mechanism Of Brilliant Green Dye Onto Acid-Modified Mesoporous Volcanic Pumice, Suchada Sawasdee, Prachart Watcharabundit

Applied Environmental Research

Water pollution is a major problem in the environment. The important one is the dying effluent from the textile industry. Dye effluent has affected human health and aquatic life. Recently, natural adsorbents have been most commonly used for dye treatment wastewater. This study explores the adsorption mechanism of brilliant green onto HCl-modified pumice. It involves a comparative analysis of the raw and HCl-modified pumice's characterization and adsorption properties. The adsorption experiments were carried out by considering several parameters, such as pH, contact time, initial dye concentrations, and temperatures. The research indicated that the raw and acid-treated pumice possess Si-OH and …

Comparison Of Metal-Carbenoid Reactions Of Β-2-Five-Membered Heteroaryl Substituted Α,Β-Unsaturated Ketones, Kumsal Eroğlu, Olcay Anaç, Füsun Şeyma Kişkan

Turkish Journal of Chemistry

In this study, β-2-heteroaryl substituted (N-methyl 2-pyrrolyl, 2-thiophenyl, 2-furyl) α,β-unsaturated ketones were reacted with two α-diazo carbonyl compounds that had different characteristics (dimethyl diazo malonate and 1-diazo-1-phenyl-propane-2-one) in the presence of both copper and rhodium catalysts. In the case of reactions with N-methyl 2-pyrrolyl α,β-unsaturated ketones, the major product was the insertion derivative. However, in the reactions of 2-thiophenyl and 2-furyl α,β-unsaturated ketones with dimethyl diazomalonate (acceptor-acceptor disubstituted), only dihydrofuran products were formed over carbonyl ylides. When 2-thiophenyl and 2-furyl α,β-unsaturated ketones were reacted with 1-diazo-1-phenyl-propane-2-one (donor-acceptor disubstituted), 1-phenylpropane-1,2-dione was obtained under our reaction conditions.

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 …

A Computational Study On The Impact Of Anchoring Groups On The Optical And Electronic Properties Of Triphenylamine-Based Dyes For Dye-Sensitized Solar Cell Applications, Geradius Deogratias, Grace Kinunda

Tanzania Journal of Science

Anchoring groups are crucial for enhancing the performance of dye-sensitized solar cells (DSSCs). For instance, cyanoacrylic acid serves as the primary anchoring group in DSSC due to its crucial elements required for effective electron transport. However, it suffers from degradation. To address this limitation, this study proposes alternative cyano-based anchoring groups for sensitizers. Density functional theory (DFT) and time-dependent DFT were used to investigate the optical and electronic properties of the dyes. The studied dyes (excluding the dye containing OH group) displayed three absorption bands within the visible and NIR regions. Low-energy peaks ranged from 498 to 576 nm, corresponding …

Discovery Of Small-Molecule Inhibitors For The Β-Catenin/B-Cell Lymphoma 9 Protein-Protein Interaction., Zilu Li

USF Tampa Graduate Theses and Dissertations

The Wnt/β-catenin signaling pathway is associated with activating genes that support cell proliferation, differentiation, and survival. Excessive activation of Wnt/β‐catenin signaling has been associated with development of several types of cancer and activation of stem-like cancer cells. Direct targeting of β‐catenin, the central hub in this signaling pathway, is a promising strategy to suppress the hyperactive β‐catenin signaling but has proven to be highlychallenging. Substantial efforts have been made to discover compounds that bind with β‐catenin, block β‐catenin mediated protein–protein interactions (PPIs) and suppress β‐catenin signaling. β‐catenin/BCL9 PPI has a smaller contacting area (1450 Å2) and a moderate binding affinity …

A Computational Kinetics Model To Quantify Radiation Induced Chemical Products Of Atmospheric Gas Mixtures, Patrick Ables

Dissertations

This research is focused on the development of a computational model which will calculate the effects of radiation on the chemical composition of the atmosphere. The approach utilizes the open-source chemical kinetics toolkit Cantera to model the creation of radiation-induced reactant species within irradiated air mixtures. Chemical solutions are iteratively stepped toward chemical equilibrium within a ‘constantly stirred’ (homogeneous) reactor of fixed volume. Three different radiation chemistry models are implemented in several different pulsed and continuous radiation schemes. The first model includes the mechanisms and rates of a pulse radiation model from the literature to test the validity of the …

The Driving Effects Of Common Atmospheric Molecules For Formation Of Clusters: The Case Of Sulfuric Acid, Formic Acid, Hydrochloric Acid, Ammonia, And Dimethylamine, Olivia M. Longsworth, Conor J. Bready, George C. Shields

Open Access Fund Publications

One of the main sources of uncertainty for understanding global warming is understanding the formation of larger secondary aerosols. The beginning stages start with the formation of prenucleation complexes from precursor monomers of acids, bases, and organic molecules. The detailed interactions responsible for prenucleation and subsequent aerosol formation are difficult to decipher experimentally. We present a computational chemistry study of the interactions between three different acid molecules and two different bases. By combining a comprehensive search routine covering many thousands of configurations at the semiempirical level with high level quantum chemical calculations of approximately 1000 clusters for every possible combination …

New Methods Of Selectivity Using Electrochemistry, Qiwei Jing

Arts & Sciences Graduate Student Theses and Dissertations

This project has been working on introducing new type of method to induce chemoselectivity into electrochemical reactions by modifying the surface of an electrode and then confining chemical reactions to the region of the reaction close to that surface. The goal is to translate the extremely high levels of site-selectivity seen in chemical reactions on a microelectrode array into a tool for preparative synthetic reactions.As a proof-of-principle experiment, Pt-anode was coated with a diblock copolymer that is known to have an affinity for pyrene groups. The electrode is then used in the oxidation of two alcohol substrates: one having the …