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Magnetron Sputtering of Transition Metal Oxynitrides and Their Characterization with Auger Electron Spectroscopy and X-ray Photoelectron Spectroscopy

Description: Transition metal oxynitrides are of growing interest for their use as electrocatalyst for nitrogen reduction reaction. The metals in the oxynitride used for catalytic process are stabilized in intermediate state for effective activation of nitrogen. Therefore, studying the interaction of metal oxynitrides films to ambient exposure is necessary. Here, sputter deposited vanadium oxynitride is compared to cobalt oxynitride using insitu Auger electron spectroscopy (AES), ex situ X-ray photoelectron… more
Date: May 2023
Creator: Adesope, Qasim Adewale
Item Type: Refine your search to only Thesis or Dissertation
open access

One-Step Synthesis of 1,3,4-Oxadiazines, 4,5,6,7-Tetrahydro-1h-Indoles, and Functionalized Benzo[B]Carbazoles Catalyzed by Rare Earth Metal Triflates and Cooperative Enamine-Bronsted Acid

Description: Design and development of novel one-step reactions that produce nitrogen-containing scaffolds is an invaluable area of chemistry due to the abundance of these moieties in natural products and biologically active molecules. Discovering novel methods using uncommon substrates and rare earth metals to access these significant scaffolds present a challenge. Over the course of my doctoral studies, I have designed, developed and optimized novel reactions by using rarely known substrates and rare eart… more
Date: May 2023
Creator: Cortes Vazquez, Jose
Item Type: Refine your search to only Thesis or Dissertation

Theoretical Studies of Photoactive Metal Complexes with Applications in C-H Functionalization and Quantum Computing

Description: Previous work was successful at delineating reaction pathways for the photoactivated synthesis of an amine, [CztBu(PyriPr)(NH2−PyriPr)], by double intramolecular C−H activation and functionalization via irradiating a metal(II) azido complex, [CztBu(PyriPr)2NiN3. The present work seeks to expand upon earlier research, and to substitute the metal with iron or cobalt, and to expand the study to photocatalyzed intermolecular C−H activation and functionalization of organic substrates. Density functi… more
This item is restricted from view until June 1, 2024.
Date: May 2023
Creator: Alamo Velazquez, Domllermut C.
Item Type: Refine your search to only Thesis or Dissertation

Parameterization of Ionic Liquids and Applications in Various Chemical Systems

Description: In this work, the development of parameters for a series of imidazolium-based ionic liquids molecules, now included in the AMOEBA force field, is discussed. The quality of obtained parameters is tested in a variety of calculations to reproduce structural, thermodynamic, and transport properties. First, it is proposed a novel method to parameterize in a faster, and more efficient way parameters for the AMOEBA force field that can be applied to any imidazolim-based cation. Second, AMOEBA-IL polar… more
This item is restricted from view until January 1, 2028.
Date: December 2022
Creator: Vazquez Cervantes, Jose Enrique
Item Type: Refine your search to only Thesis or Dissertation

An Investigation into the Micromechanical and Corrosion Properties of Additively Manufactured Stainless Steel 316L

Description: In this thesis, micro-mechanical properties and corrosion resistance of laser powder bed fusion (L-PBF) processed additive manufactured (AM) 316L stainless steel parts were investigated for different combinations of processing parameters. Various laser powers were employed for the fabrication of all AM 316L stainless steel parts. Nanoindentation, areal roughness, and electron backscattered diffraction (EBSD) characterization were used to characterize the surface of the AM samples prior to corro… more
This item is restricted from view until January 1, 2028.
Date: December 2022
Creator: England, Jennifer
Item Type: Refine your search to only Thesis or Dissertation

Aromaticity, Supramolecular Stacks, and Luminescence Properties of Cyclic Trinuclear Complexes

Description: The dissertation covers three major topics: metal-assisted aromaticity, synthetic approaches to tailor donor-acceptor supramolecular stacks, and photoluminescence properties of cyclic trinuclear complexes (CTCs) of d10 metals. First, multiple theoretical approaches are adapted to discuss in detail the origin of aromaticity of CTCs, putting forward a metal-assisted aromaticity model. Next are the discoveries of donor-acceptor stacked CTC–CTC' complexes from both experimental and computational pe… more
Date: December 2022
Creator: Lu, Zhou
Item Type: Refine your search to only Thesis or Dissertation

Nanofluidic Membrane Based on Covalent Organic Framework: Design Strategies and Applications

Description: Nanofluidic is an emerging field of applying fluid properties in nanochannels or nanostructures. The nanoporous channel with a pore size of less than 100 nm will strongly affect the motion of the fluid. Meanwhile, the pore environment, such as hydrophilic and hydrophobic properties, charge density, and host-guest recognition would be crucial for the transportation of molecules and ions in the pore. This thesis is focused on the synthesis, characterization of nanofluidic membranes and their appl… more
Date: December 2022
Creator: Zhu, Changjia
Item Type: Refine your search to only Thesis or Dissertation

Investigation of Ionic Liquid Phases for Chromatographic Separation of Fentanyl Analogues

Description: Opioid abuse and in particular fentanyl, a synthetic opioid, has been of concern in the last decade. Fentanyl is an illicit drug of concern to due to its prevalence and potency. Research to date has focused on supporting law enforcement by developing methods suitable for chemical profiling and identifying fentanyl from various matrices. However, methods geared towards analysis of fentanyl isomeric analogues are rare. Analysis of isomers is challenging due to similar mass spectral fragmentation … more
This item is restricted from view until January 1, 2028.
Date: December 2022
Creator: Smart, Katherine Rose
Item Type: Refine your search to only Thesis or Dissertation

Porous Materials as Drug Delivery Systems

Description: The porous materials discussed in this dissertation are metal-organic frameworks (MOFs) and porous liquids. Due to their high surface areas, tunable structures, and controllable porosities, MOFs have been explored for a wide variety of drug delivery applications. In chapter 2, MOFs have been used as magnetothermal-triggered release carriers through spatially distributed iron oxide nanoparticles within MOF matrix as a magnetic heating mediator and surface-grafted thermal-responsive nanocap as an… more
This item is restricted from view until January 1, 2028.
Date: December 2022
Creator: Ge, Xueying
Item Type: Refine your search to only Thesis or Dissertation

Sulfur-Based Organic Compounds as Novel Corrosion Inhibitors for Brass and Aluminum Alloy Protection in Acid Cleaning Solutions

Description: In this study, thiol and two disulfide compounds have been tested as new corrosion inhibitors for brass and aluminum alloys. Pyridine-2-thiol and 2,2'-dipyridyl disulfide were tested for brass alloys in 0.5 M H2SO4 solution and both inhibitors showed excellent corrosion protection against the aggressive corrosive ion attack. Both inhibitors adsorbed to brass surface forming a protective film via a chemisorption process. XPS studies showed formation of Cu-S bond which allows these molecules to c… more
This item is restricted from view until January 1, 2028.
Date: December 2022
Creator: Karunarathne, Darshan Jayasinghe
Item Type: Refine your search to only Thesis or Dissertation
open access

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
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