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Ranaspumin Protein Characterization and Applications for Both Environmental and Medical Purposes

Description: The Túngara frog (Engystomops pustulosus) from Central America creates a bio-foam that protects their young from dehydration, microbial degradation, and even predators during early development. The foam is composed of unique proteins known as Ranaspumin 1-6 (RSN 1-6). These RSN proteins have been synthetically synthesized and verified with Circular Dichroism (CD) to determine their critical micelle concentration, antimicrobial properties, and stability at varying temperatures and pH ranges. Thr… more
Date: December 2022
Creator: Koerber, Rachel
Item Type: Refine your search to only Thesis or Dissertation
open access

Earth Abundant Transition Metal Catalysts for Activation and Functionalization of Light Hydrocarbons

Description: Light hydrocarbons activations, functionalization, and reactions have been a subjects of catalysis research for decades but dominated by the rarer and more expensive noble metals. Switching over to using the more earth abundant third row transition metals could be more economical and less toxic but come with their own challenges. Their use as catalysts with light hydrocarbons could be employed better utilize and more efficiently use our hydrocarbon resources that the world still depends on.
Date: August 2022
Creator: Grumbles, William M
Item Type: Refine your search to only Thesis or Dissertation

Bifunctional Enamine‐Metal Lewis Acid Catalysis and α-Enaminones for Cyclization Reactions

Description: The use of enamines continues to be an important tool in organic syntheses as both a catalyst and reactant. The addition of metal catalysts coupled with enamine catalysis has generated many reactions that normally would not occur separately. However, catalysts' incompatibility is an issue that we wish to solve allowing new chemistry to occur without hindrance. The use of enamines has continued to be a well-studied area of organic chemistry, but the field is ripe for different types of enamines … more
This item is restricted from view until September 1, 2024.
Date: August 2022
Creator: Davis, Jacqkis
Item Type: Refine your search to only Thesis or Dissertation
open access

Ultrafast Charge Transfer in Donor-Acceptor Push-Pull Constructs

Description: Ultrafast charge and electron transfer, primary events in artificial photosynthesis, are key in solar energy harvesting. This dissertation provides insight into photo-induced charge and electron transfer in the donor and acceptor constructs built using a range of donor and acceptor entities, including transition metal dichalcogenides (TMDs, molybdenum disulfide (MoS2), and tungsten disulfide (WS2)), N-doped graphene, diketopyrrolopyrrol (DPP), boron-dipyrromethene (BODIPY), benzothiadiazole (BT… more
Date: August 2022
Creator: Jang, Young Woo
Item Type: Refine your search to only Thesis or Dissertation

"You get what you pay for" vs "You can alchemize": Investigating Discovery Research Experiences in Inorganic Chemistry/Chemistry Education via an Undergraduate Instructional Laboratory

Description: Synthesis of d10 complexes of monovalent coinage metals, copper(I) and gold(I), with dithiophosphinate/diphosphine ligands -- along with their targeted characterization and screening for inorganic or organic light emitting diodes (LEDs or OLEDs, respectively) -- represents the main scope of this dissertation's scientific contribution in inorganic and materials chemistry. Photophysical studies were undertaken to quantify the phosphorescence properties of the materials in the functional forms req… more
This item is restricted from view until September 1, 2027.
Date: August 2022
Creator: Bodenstedt, Kurt Wallace
Item Type: Refine your search to only Thesis or Dissertation

The Development of the Attitudes Towards Organic Chemistry Instrument

Description: In this study, undergraduate student attitudes towards organic chemistry and the influences that shape those attitudes were explored using the Attitudes Towards Organic Chemistry Instrument (ATOC) to collect both qualitative and quantitative data. The findings from the qualitative ATOC items provide evidence that students displayed a wide range of attitudes towards organic chemistry, including positive, negative, neutral, and blended attitudes. Five major influences were shown to have shaped th… more
This item is restricted from view until September 1, 2024.
Date: August 2022
Creator: Collini, Melissa Anne
Item Type: Refine your search to only Thesis or Dissertation

Computational Investigations of Catalytic Activity by Metal-Containing Complexes

Description: This dissertation delves into the catalytic activity of multiple metal-containing complexes with an emphasis on the activation of C–H bonds in small molecules and olefin oligomerization. The research contained in these works employs computational methodologies to better understand the thermodynamics and kinetics of the reactions. Computations can be used to quickly identify novel models and find ideal substitutions for improved catalyst design. Within this dissertation, multiple molecules of di… more
Date: August 2022
Creator: Carter, Carly Catherine
Item Type: Refine your search to only Thesis or Dissertation

Chemically Optimized Cu Etch Bath Systems for High-Density Interconnects and the FTIR Operando Exploration of the Nitrogen Reduction Reaction on a Vanadium Oxynitride Electrocatalyst

Description: Printed circuit board manufacturing involves subtractive copper (Cu) etching where fine features are developed with a specific spatial resolution and etch profile of the Cu interconnects. A UV-Vis ATR metrology, to characterize the chemical transitions, has been developed to monitor the state of the bath by an in-situ measurement. This method provides a direct correlation of the Cu etch bath and was able to predict a 35% lower etch rate that was not predicted by the three current monitoring met… more
This item is restricted from view until September 1, 2027.
Date: August 2022
Creator: Caperton, Joshua M
Item Type: Refine your search to only Thesis or Dissertation

Computational Modeling of Cancer-Related Mutations in DNA Repair Enzymes Using Molecular Dynamics and Quantum Mechanics/Molecular Mechanics

Description: This dissertation details the use of computational methods to understand the effect that cancer-related mutations have on proteins that complex with nucleic acids. Firstly, we perform molecular dynamics (MD) simulations of various mutations in DNA polymerase κ (pol κ). Through an experimental collaboration, we classify the mutations as more or less active than the wild type complex, depending upon the incoming nucleotide triphosphate. From these classifications we use quantum mechanics/molecula… more
Date: May 2022
Creator: Leddin, Emmett Michael
Item Type: Refine your search to only Thesis or Dissertation

Machine Learning in Computational Chemistry

Description: Machine learning and artificial intelligence are increasingly becoming mainstream in our daily lives, from smart algorithms that recognize us online to cars that can drive themselves. In this defense, the intersection of machine learning and computational chemistry are applied to the generation of new PFAS molecules that are less toxic than those currently used today without sacrificing the unique properties that make them desirable for industrial use. Additionally, machine learning is used t… more
This item is restricted from view until June 1, 2024.
Date: May 2022
Creator: Kuntz, David Micah
Item Type: Refine your search to only Thesis or Dissertation

Metal-Macrocyclic Frameworks based on Aza-Macrocycles: Design Strategies and Applications

Description: The present thesis mainly proposes to explore the potential of aza-macrocycles in metal-organic frameworks (MOFs) for applications related to unprecedented open macrocycle cavities. Strategies such as direct arylation of secondary amines as well as multidentate coordination were applied to constrain the intramolecular flexibility of as-obtained macrocyclic compounds. Several desired materials, i.e. MMCF-4, MMCF-5/MMCF-5t/MMCF-5t-aa, MMCF-5, HMMCF-1, were obtained. They are proved superior to tr… more
Date: May 2022
Creator: Ren, Junyu
Item Type: Refine your search to only Thesis or Dissertation

In vitro Biomedical Application and Photothermal Therapy Evaluation of Gold Complexes and Gold Nanoparticles

Description: Plasmonic photothermal therapy (PPTT) has a rising promise for treating different cancer cells such as lymphoma or stomach cancer. Technique development of PPTT using metallic nanoparticles is developed upon a modification of the irradiation therapy using two major changes: using a less harmful visible amber light (excluding blue light) and using gold-loaded biocompatible nanoparticles. Acrylate nanoparticles were loaded with desired types of gold nanoparticles at different sizes. The gold-load… more
This item is restricted from view until June 1, 2024.
Date: May 2022
Creator: Shennara, Khaled A
Item Type: Refine your search to only Thesis or Dissertation
open access

Synthesis and Characterization of Vanadium and Cobalt Oxynitride Surface Chemical and Electronic Structure for Electrochemical Reduction of N2 to NH3

Description: Cobalt oxynitride films formed by magnetron sputter deposition of a Co target in N2 or NH3 plasma or, alternatively, by NH3 plasma nitridation of a Co film deposited on Si(100), show a divergence of properties arising from (a) N and O interactions for N and O atoms bonded to each other or through a common metal center and (b) the oxophilicity of the metal center itself. Core and valence band X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and plane wave density functional theor… more
Date: May 2022
Creator: Osonkie, Adaeze
Item Type: Refine your search to only Thesis or Dissertation
open access

Novel LC-MS Method for the Analysis of Beta-Hydroxybutyric Acid (BHB) in Health Formulations

Description: The rise of nutraceutical health formulations has increased the need for more stringent analytical testing methods. Complex matrices present a new problem when determining concentration of compounds of interest. The presented method uses LC-MS analysis with a novel sample preparation method in the determination of Beta-hydroxybutyric acid in health formulations. The use of an aqueous analytical column allows for separations of polar compounds after non-polar compounds are removed through C18 pa… more
Date: May 2022
Creator: Smith, Garret Mackenzie
Item Type: Refine your search to only Thesis or Dissertation
open access

Deposition and Characterization of Thin Metal Oxide Heterostructures for Electronic and Magnetic Device Applications

Description: The first study investigated the deposition and characterization of the CoO and Co3O4 phases of cobalt oxide. It was determined that both phases can be easily distinguishable by XPS, LEED and EELS and grown by only altering the oxygen partial pressure during MBE deposition. This fundamental knowledge gives a foundation for further experiments involving graphene growth on cobalt oxides. The second study focused on the layer-by-layer growth of graphene on another metal oxide, MgO. Past research g… more
Date: May 2022
Creator: Ladewig, Chad Samuel
Item Type: Refine your search to only Thesis or Dissertation
open access

Porphyrin and BODIPY Derived Donor-Acceptor Multi-Modular Systems: Synthesis, and Excited State Energy and Electron Transfer Studies

Description: This dissertation demonstrates that it is possible to create a donor-acceptor system that can transform sunlight into electrons. By using site-directed synthesis, it was possible to create a novel trans-A2B2 porphyrin. In the pursuit of creating a supramolecular system, both the novel (TPA-BT)2ZnP and C60imidazole combined in solution such that the nitrogenous lone pair of C60 imidazole would coordinate axially to the zinc atom in the porphyrin. The conjugates' characterization utilized spectra… more
Date: May 2022
Creator: Benitz, Alejandro Daniel
Item Type: Refine your search to only Thesis or Dissertation

Pressure Controlled Topochemical Polymerization in Two-Dimensional Hybrid Perovskite

Description: Mechanical pressure offers unique control over the energy landscape of chemical reactions, opening up pathways that are inaccessible through conventional thermochemistry. We hypothesize that the reduced dimensionality defines the conformational space of the high-pressure reaction, giving rise to new selectivity that is unavailable in 3D systems. Here, we demonstrate this concept through the pressure-controlled topochemical polymerization of the diacetylene molecule deca‐3,5‐diyn‐1‐amine (DDA) i… more
Date: December 2021
Creator: Abu-Amara, Lama Marwan
Item Type: Refine your search to only Thesis or Dissertation
open access

Linearly-Annulated, Functionalized, β,β'-π-Extended Porphyrins

Description: Benzannulation to porphyrin 2,3 positions has previously been accomplished using various methodologies in the past century, yet there remain limited methodologies to both annulate to the porphyrin periphery and add functional moieties that can then be derivatized for diverse applications. This dissertation describes the development of synthetic routes and characterization of a variety of linearly-annulated, functionalized, β,β'-π-extended porphyrins. There are five chapters in this dissertation… more
Date: December 2021
Creator: Moss, Austen Edmond
Item Type: Refine your search to only Thesis or Dissertation
open access

Instrumental Development and Implementation of Portable Membrane Inlet Mass Spectrometry for Homeland Security and Environmental Applications

Description: A rapidly growing topic of great interest is the adaptation of benchtop analytical instrumentation for use in outdoor harsh environments. Some of the areas that stand to benefit from field instrumentation development include government agencies involved with the preservation of the environment and institutions responsible for the safety of the general public. Detection systems are at the forefront of the miniaturization movement as the interest in analyte identification and quantitation appears… more
Date: December 2021
Creator: Anguiano Virgen, Camila
Item Type: Refine your search to only Thesis or Dissertation

Corrosion Mechanism and Prevention of Wire Bonded Device in Microelectronic Manufacturing and Spectroscopic Investigation of Copper Etch Chemical Equilibria for High Density Interconnect Application

Description: In the first part of this dissertation work, Al bond pad corrosion behavior was investigated in the presence of common industrial contaminants such as chloride (Cl-) and fluoride (F-). Al corrosion while in direct contact with Cu displayed rapid hydrogen (H2) gas evolution and dendrite propagation. In contrast, Al without bimetallic contact showed only minor surface roughening. This observed difference in the corrosion mechanism between Cl- and F- is attributed to the solubility of the corrosio… more
Date: December 2021
Creator: Ashok Kumar, Goutham Issac
Item Type: Refine your search to only Thesis or Dissertation
open access

Donor-Acceptor Artificial Photosynthetic Systems: Ultrafast Energy and Electron Transfer

Description: Mother nature has laid out a beautiful blueprint to capture sunlight and convert to usable form of energy. Inspired by nature, donor-acceptor systems are predominantly studied for their light harvesting applications. This dissertation explores new donor-acceptor systems by studying their photochemical properties useful in building artificial photosynthetic systems. The systems studied are divided into phthalocyanine-porphyrin-fullerene-based, perylenediimide-based, and aluminum porphyrin-based … more
Date: December 2021
Creator: Seetharaman, Sairaman
Item Type: Refine your search to only Thesis or Dissertation
open access

Computational Studies of the Photophysical, Structural, and Catalytic Properties of Complex Chemical Systems

Description: Computational chemistry employs mathematical algorithms, statistics, and large databases to integrate chemical theory with experimental observations. Computational modeling allows us to make predictions concerning molecular properties and reactivity that ultimately lead to accurate assessment of the most important fundamental properties of chemical systems. Advances in theoretical techniques and computer power have dramatically increased the usefulness and importance of computational chemistry … more
Date: May 2021
Creator: Melancon, Kortney
Item Type: Refine your search to only Thesis or Dissertation
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