Physical Sciences and Mathematics Commons^™

Production And Applications Of Formaldehyde-Free Phenolic Resins Using 5-Hydroxymethylfurfural Derived From Glucose In-Situ, Yongsheng Zhang

Electronic Thesis and Dissertation Repository

The phenol-formaldehyde (PF) resin manufacturing industry is facing a growing challenge with respect to concerns over human health, due to the use of carcinogenic formaldehyde and sustainability due to the use of petroleum-based phenol in PF resin manufacture. Glucose and its derivative, 5-hydroxymethylfurfural (5-HMF), have proven to be potential substitutes for formaldehyde in the synthesis of phenolic novolac resins.

This thesis investigated a number of glucose and 5-HMF resin systems including the curing of phenol-glucose novolac resin (PG) with a bis-phenol-A type epoxy. The curing process was modeled according to the Sestak-Berggren equation (S, B) using Málek methods. This was …

Polyglyoxylates: A New Class Of Triggerable Self-Immolative Polymers, Bo Fan

Electronic Thesis and Dissertation Repository

Self-immolative polymers, which degrade by an end-to-end depolymerization mechanism in response to the cleavage of a stabilizing end-cap from the polymer terminus, are of increasing interest for a wide variety of applications ranging from sensors to controlled release. However, the preparation of these materials often requires expensive, multi-step monomer syntheses and the degradation products such as quinone methides or phthalaldehydes are potentially toxic to humans and the environment. We demonstrate here that polyglyxoylates can serve as a new and versatile class of self-immolative polymers. Polymerization of the commercially available monomer ethyl glyoxylate, followed by end-capping with a 6-nitroveratryl carbonate provides …

Exploring The Reactivity Of Donor-Acceptor Cyclopropanes And The Synthesis Of (+/-)-Quebrachamine, Huck K. Grover

Electronic Thesis and Dissertation Repository

The development and utility of cyclopropanes is an ever-growing field within organic chemistry. In particular, donor-acceptor cyclopropanes have been used in a vast array of methods to access a variety of different hetero and carbocyclic molecular scaffolds. Recently, we have developed a Zn(NTf2)2 catalyzed tandem reaction consisting of a nucleophilic ringopening of 1,1-cyclopropanediesters by 2-alkynyl indoles followed by a Conia-ene ring closure, resulting in the efficient one-step synthesis of tetrahydrocarbazoles. These adducts may be further elaborated to carbazoles. The scope and limitations of this method were determined along with a mechanistic study into the function of the zinc catalyst. In …

Bidentate Ferrocenyl-Dithiol Reagents For Nanocluster Surface Functionalization, Yiyi Liu

Electronic Thesis and Dissertation Repository

Previous work using monodentate ferrocenyl-chalcogen reagents for nanocluster surface functionalization has indicated an effective way to involve ferrocene moieties onto the surface of these frameworks. However, the abilities of the large polynuclear nanocluster with ferrocene rich surface to form crystalline materials suitable for single crystal X-ray analysis proved to be limited. New bidentate ferrocenyl-chalcogen reagents have been synthesized and characterized in order to probe their ability in this case.

The preparation of new bidentate ferrocenyl chalcogen reagents 1,1’-fc(C{O}OCH₂CH₂SH)₂ (fc = ferrocenyl) and 1,1’-fc(C{O}NHCH₂CH₂SH)₂ are presented. Furthermore, the preparation of silylated …

Poly(Ester Amide) And Poly(Ethyl Glyoxylate) Nanoparticles For Controlled Drug Release, Amira Mohamed Moustafa

Electronic Thesis and Dissertation Repository

The objective of this research was to develop polymeric nanoparticles (NPs) having improved drug release properties for drug delivery. Poly(ester amide)s (PEAs) are promising biodegradable polymers. PEA NPs were prepared via emulsification-evaporation and salting-out methods and optimized through by varying different processing parameters. Polymer-model drug conjugates based on PEAs containing L-aspartic acid and rhodamine B were synthesized and used for NP preparation. Release behavior was studied and compared to a control system with physically encapsulated rhodamine B. It was shown that the release of rhodamine B from the covalent system did not show the burst effect and exhibited a slower …

Scale-Up Methodology For Bench-Scale Slurry Photocatalytic Reactors Using Combined Irradiation And Kinetic Modelling, Patricio J. Valades Pelayo

Electronic Thesis and Dissertation Repository

The present study focuses on developing a predictive methodology to scale-up a slurry annular photoreactor using a TiO₂ Degussa P25 from the bench-scale to a pilot-plant scale. The bench-scale photoreactor is a Photo-CREC-Water II, a 2.65 L internally-irradiated slurry annular photocatalytic reactor. The pilot-plant scale photoreactor is a Photo-CREC Water Solar Simulator, a 9.8 L pilot-plant photoreactor, externally irradiated by eight lamps.

The adopted methodology allows the independent validation of radiative and kinetic models avoiding cross-correlation issues. The proposed approach involves two Monte Carlo methods, to model the Radiative Transfer Equation (RTE) inside each photoreactor. With this end, a …

Diffusion And Adsorption Coefficients Of Aromatic Hydrocarbons In Gas Chromatography Capillary Columns, Gabriela Navarro Tovar

Electronic Thesis and Dissertation Repository

This study focuses on a mathematical description of aromatic species elution peaks from a gas chromatographic BPX5 capillary column. Using the chromatographic peaks, statistical moments are calculated for toluene, naphthalene, phenol and 2-naphthol. This thesis reports two modelling approaches involving laminar gas flow, distribution coefficients (K_s) and diffusion coefficients in the stationary phase (D_s).

Firstly, a model with equilibrium adsorption is considered to describe symmetric peaks for toluene and naphthalene. Moreover, a model with non-equilibrium adsorption is proposed to describe asymmetric peaks of phenol and 2-napthol. In addition to the K_s and D …

Photochromic Molecular Materials For The Controlled Organization Of Nanoparticles, Kristen Elise Snell

Electronic Thesis and Dissertation Repository

The displacement of polystyrene nanoparticles promoted by bulk azo mass transfer using interferential light illumination will be discussed. For this a variety of different push pull small azo molecules were synthesis and characterized, changing the polarity, hydrophobicity and bulky groups around the azo moiety. These small dyes appear to orientate quicker than similarly report azo polymers, of entanglement of the azobenzene group in the polymeric backbone. These dyes were used to form surface relief grating on the thin films due to the bulk mass transfer. This mass transfer was exploited to align polystyrene nanoparticles in the crests and troughs of …

Effect Of Gamma Radiation On The Interfacial Reactions And Transfer Processes Of Phosphonium-Based Ionic Liquids With Carbon Steel, Ryan P. Morco

Electronic Thesis and Dissertation Repository

This thesis presents work on the effects of ionizing radiation on phosphonium-based ionic liquids (ILs). Ionic liquids are known for their tunable properties which make them attractive options for applications for the separation and sequestration of metal ions from spent nuclear fuels, and candidate lubricants for systems under severe conditions. The high radiation environment found in spent fuel processing may decompose the solvents (ILs) used in the process and affect their separation efficiency. The radiolytic decomposition products can also alter the physical and chemical properties of an IL in ways which can affect the potential corrosion of metal alloys in …

Radiation Induced Corrosion Of Stellite-6, Mehran Behazin

Electronic Thesis and Dissertation Repository

This thesis presents a study on the aqueous corrosion of a cobalt-based alloy, Stellite-6. Since aqueous corrosion kinetics are strongly influenced by water chemistry conditions (pH, temperature, and redox agents), a systematic study of Stellite-6 corrosion was carried out. The aim was to develop an ability to predict corrosion behaviour and particularly metal dissolution rates for cobalt alloys under a range of conditions. The work focused on a study of the influence of ionizing radiation on corrosion. This is of particular interest in the nuclear industry where radiation fields are present. Ionizing radiation creates oxidizing radiolysis products and alters the …

Investigation Of The Crystallization Of Dnl-6 And Ft-Raman Spectroscopic Investigation Of Guest Molecules In Mofs, Maxwell Goldman

Electronic Thesis and Dissertation Repository

Microporous solids are a widely used material in adsorption, storage and catalysis. In this thesis, the crystallization of the silcoaluminaphosphate DNL-6 was characterized using powder X-ray diffraction and solid state nuclear magnetic resonance. Two crystallization routes of the SAPO DNL-6 were studied, which are the hydrothermal method and the dry-gel conversion method. Both methods followed the same crystallization pathway and showed a layered intermediate that is then transformed into DNL-6. The reaction requires two templating agents to create the RHO topology and silicon substitutes into the framework by replacing single phosphorous atoms.

This thesis contains the conformational analysis of halocarbons …

The Development Of Metal-Organic Compounds For Use As Molecular Imaging Agents, Emily J. Simpson

Electronic Thesis and Dissertation Repository

Molecular imaging probes allow for the non-invasive diagnosis of many diseases through the use of a targeting entity for site specific delivery, as well as a signal for external visualization of probe accumulation in the body. This thesis will focus on the development of new approaches to synthesize targeting peptides and chelators for radionuclide incorporation towards the design of novel molecular imaging probes.

Histidine is a tridentate chelator that can be attached in a pendant fashion to a biomolecule in order to coordinate technetium-99m. Once coordinated, it forms a neutral complex that is capable of forming diastereomers with inverted stereochemistry …

Gamma-Radiolysis Kinetics Of Liquid, Vapour And Supercritical Water, Nastaran Yousefi

Electronic Thesis and Dissertation Repository

Inadequate understanding of radiation-induced water chemistry under supercritical conditions has been identified as one of the important obstacles in the development of a supercritical water-cooled reactor. Radiolysis of supercritical water generates a variety of redox reactive species, but their persistence in supercritical water is not well understood. This thesis describes the work performed towards addressing this deficiency: (1) the development of a reliable experimental method to determine the concentrations of water radiolysis products, primarily H₂, O₂ and H₂O₂, formed under g-irradiation of sub- and supercritical water (SCW), (2) the expansion of the application …

Optimization Of P-Type Czts Nanocrystal Thin Film Layers For Applications In Low Cost Photovoltaic Devices, Kyle S.B. Jeffs

Electronic Thesis and Dissertation Repository

In this thesis Cu2ZnSnS4 nanocrystal synthesis was optimized by way of photoelectrochemical measurements through tuning the stoichiometry. Formation of a Cu2ZnSnS4 light-absorbing layer was studied using multiple depositions methods. These included dropcasting, electrophoretic deposition, and use of 3-mercaptopropyl trimethoxysilane as a chemical linker. Dropcasting samples were compared according to the solvents used to suspend the nanocrystals. Photoelectrochemical measurements were used to compare dropcasting with electrophoretic deposition and use of 3-mercaptopropyl trimethoxysilane as a chemical linker. Dropcasting was shown to be the least effective method of depositing the light-absorbing layer. Samples prepared by electrophoretic deposition were optimized according to a number …

Synthesis Of Carbohydrate Functionalized Dendrons For Use As Multivalent Scaffold And In Self-Assembled Structures, Namrata Jain

Electronic Thesis and Dissertation Repository

Carbohydrates are implicated in a large number of biological processes ranging from cell-cell interactions to bacterial and viral infection. Lectins are carbohydrate-binding proteins that are generally specific for certain sugars. However, typical carbohydrate–lectin interactions tend to have very low monomeric binding affinities. In many cases, the binding of saccharide ligands by protein receptors can be improved significantly through the attachment of multiple saccharide residues to a common support. Dendronized polymers constitute a class of macromolecules whose nanoscale size, rigidity, and functionality can be controlled with precision by tuning their molecular architecture. It is hypothesized that due to their large size …

The Application Of Novel Donor Acceptor Cyclopropanes In The Synthesis Of Linearly Fused Tricyclic Triazoles, Michelle E. Flisar

Electronic Thesis and Dissertation Repository

Previous work in the Kerr group has shown the success of donor-acceptor cyclopropanes as substrates in a variety of synthetic reactions; this document will apply the use of donor acceptor cyclopropanes in various synthetic reactions. This was done using a 2-substituted 1,1-cyclopropanediester, in the Overman Rearrangement, which has yet to be explored using DA cyclopropanes. Another useful DA cyclopropane is the novel acetylene-bearing donor acceptor diester cyclopropanes which would be synthetically useful in a wide variety of reactions. In particular, the Conia-ene cyclization occurred intramolecularly with this alkyne DA cyclopropane with a large library of nucleophiles. Finally, taking this acetylene-bearing …

The Synthesis And Reactivity Of Novel Donor-Acceptor Cyclopropanes And Progress Towards Pyrrolidine Alkaloids, Michael R. Emmett

Electronic Thesis and Dissertation Repository

The first chapter of this thesis focuses on the synthesis and reactivity of cyclopropane hemimalonates. The cyclopropane hemimalonates can easily be synthesized from 1,1-cyclopropanediesters. The reactivity of cyclopropane hemimalonates with indole under ultra-high pressure conditions leads to ring opened adducts that are complementary to previous research in the Kerr group. The tandem ring opening decarboxylation reaction of cyclopropane hemimalonates led to the synthesis of γ-aminobutyric acid analogues. When an external nucleophile was not present, the cyclopropane hemimalonates could rearrange to form butyrolactones in good to excellent yields. The stereochemical integrity of the cyclopropane hemimalonate is retained through this process, which …

Electrogenerated Chemiluminescence Of Gold Nanoclusters, Mahdi Hesari

Electronic Thesis and Dissertation Repository

A series of monodispersed AuNCs including Au144(SR)60, Au38(SR)24 and Au25(SR)18z (z =1-, 0 and 1+, SR=2-phenylethanethiol) were prepared. All these nanoclusters showed molecule-like optical and electrochemical properties. These two features are essential for an electrogenerated chemiluminescence or electrochemiluminescence (ECL) study. The Au144(SR)60 showed a small HOMO-LUMO gap determined by electrochemistry. No ECL light was seen in the annihilation process, while NIR ECL was observed with tri-n- propylamine (TPrA) (Chapter 2). ECL was highly efficient in the Au38(SR)24/TPrA co- reactant system. This nanocluster also showed ECL emission with benzoyl peroxide (BPO), while no ECL was detected in the annihilation route (Chapter …

Application Of Mn(Iii) Oxidative Cyclizations To Natural Product Synthesis, Bryan Landschoot

Electronic Thesis and Dissertation Repository

This work begins with a brief review of manganese(III) acetate free radical oxidative cyclization chemistry and its application toward functionalizing nitrogen containing heterocycles. Exploration of a cyclopropane ring opening reaction using indoline, and subsequent manganese(III) cyclization chemistry will be presented as a possible route towards a family of natural products called the flinderoles. Work on the construction of the core of several indole alkaloids from the genus Tabernaemontana, including tronocarpine, chippiine, and dippinine B, will be explored with utilization of manganese(III) cyclizations. Hopes of accessing an advanced common intermediate for each of these natural products will be discussed due …

New Ligands For Lanthanides And Transition Metals Toward Magnetic Resonance Imaging Contrast Agents, Melissa M. Lewis

Electronic Thesis and Dissertation Repository

MRI is a non-invasive technique used in medical imaging. Although contrast agents have been used to enhance the image generated by MRI, it still suffers the major shortcoming of low sensitivity. This has led to a thrust to develop contrast agents that improve sensitivity by relaxivity and CEST. This thesis describes attempts made to aid in the development of sensitive MRI contrast agents.

Chapter 2 investigated pH dependent reversible binding on CEST effect and relaxivity in DO3AM complexes possessing a lone p-nitrophenol arm. Unfortunately, only the Tb³⁺complex had a small CEST signal. T₁ relaxivity of the …

Oxidative Cyclizations Of Tertiary Pentenols And The Synthesis Of Β-Carboline Alkaloids, Geoffrey A. Phillips

Electronic Thesis and Dissertation Repository

This thesis describes the work carried out on two projects. The first chapter of the thesis discusses the application of the second generation Co(nmp)2 catalyst towards the oxidative cyclization of tertiary pentenols through a modified Mukaiyama aerobic oxidative cyclization procedure.

The second chapter describes the progress made towards the synthesis of β-carboline alkaloids. The total synthesis of the alkaloid natural product cyclocapitelline is detailed along with the formal synthesis of the natural product chrysotricine.

Development Of A Gallium-Containing One-Bead One-Compound Peptide Library For The Discovery Of New Molecular Imaging Probes, Fernanda C. Bononi

Electronic Thesis and Dissertation Repository

An eight amino acid one-bead one-compound (OBOC) peptide library, containing a gallium-DOTA complex, was developed in an attempt to overcome common issues associated with the later addition of radionuclides to peptide chains of imaging probes. The further addition of a radionuclide often changes the binding properties of a peptide, as it adds bulk, and possibly charges. MALDI (matrix-assisted laser desorption ionization) tandem mass spectrometry was determined to be the method of choice in order to deconvolute gallium-containing peptide sequences. The library obtained was screened against the breast cancer cell lines MDA-MB-231 and MCF-7. Positive beads were isolated and sequences were …

The Influence Of Microstructure On The Corrosion Of Magnesium Alloys, Robert M. Asmussen

Electronic Thesis and Dissertation Repository

This thesis reports a series of investigations into the influence of microstructure on the corrosion of Mg alloys. Mg alloys are prime candidates for the light-weighting of automobiles however any extensive applications are limited by their high corrosion rates. The corrosion resistance is further hindered by the susceptibility of Mg alloys to microgalvanic coupling occurring between the Mg matrix and the secondary microstructures in the alloys. This process and the individual contributions to it must be understood to improve Mg alloy design for automotive applications, develop methods for extending the lifetime of Mg alloys and developing models to successfully predict …

Tip-Enhances Raman Spectroscopy, Enabling Spectroscopy At The Nanoscale, Nastaran Kazemi Zanjani

Electronic Thesis and Dissertation Repository

The knowledge on the chemical and the structural properties of substances benefits strongly from characterization methods that can provide access to the sample’s nanoscale building blocks. Not only should the sensitivity of these methods approach a high detection limit up to single molecule, but also the accessible spatial resolution must enable chemical imaging of individual nanoscale features of the substances. High resolution imaging is often provided by electron microscopes through methods such as transmission electron microscopy (TEM) and scanning electron microscopy (STM), nevertheless, these methods lack offering chemical information. Surface-enhanced spectroscopy was developed to improve the sensitivity of the chemical …

Exploring The Synthesis And Coordination Chemistry Of Zwitterionic Main Group Compounds, Jonathan W. Dube

Electronic Thesis and Dissertation Repository

Traditionally low coordinate and low oxidation state main group compounds are isolated utilizing hard anionic donors based on carbon and nitrogen based ligands. Conversely, employing anionic phosphines for this role has been essentially unexplored. In this context, this dissertation describes the synthesis of a number of main group complexes, ranging from group 13 to group 15, utilizing the bis(phosphino)borate ligand class in a supporting role. The remote anionic borate backbone renders the complexes zwitterionic and provides access to unique compounds that possess structures, and exhibit onwards reactivity, that is very different to the analogous compounds stabilized with neutral phosphines. For …

Protein Conformational Studies By Hydrogen/Deuterium Exchange Mass Spectrometry, Antony D. Rodriguez

Electronic Thesis and Dissertation Repository

Proteins are biological macromolecules responsible for the majority of all physiological processes. In order to properly function proteins are required to adopt highly ordered structures. These structural aspects may be found within a single protein or arise from multi-protein complexes. Here hydrogen/deuterium exchange mass spectrometry (HDX-MS) is employed as a tool to determine the extent of protein higher order structure. Exposure to D₂O-based solvent causes the heavier isotope to exchange with amide hydrogens in the polypeptide backbone. This exchange is mainly dependent on protein conformation because the presence of stable hydrogen-bonded secondary structure will impede the incorporation of …

The Electrochemistry Of Hydrogen Peroxide On Uranium Dioxide And The Modelling Of Used Nuclear Fuel Corrosion Under Permanent Disposal Conditions, Linda Wu

Electronic Thesis and Dissertation Repository

This thesis reports a series of investigations examining the corrosion process of used nuclear fuel under permanent disposal conditions. The motivation of the project is that the safety assessment of deep geological disposal of spent nuclear fuel requires a fundamental understanding of the processes controlling fuel corrosion which could lead to the release of radionuclides to the geosphere from a failed container.

One primary objective of this project was to develop a computational model in order to simulate fuel corrosion under the disposal conditions. A series of simulations based on COMSOL were designed and developed to determine the influence of …

Peptidomimetic Ghs-R1a Agonists As Pet Imaging Agents For Prostate Cancer, Milan M. Fowkes

Electronic Thesis and Dissertation Repository

Contemporary diagnostic techniques for prostate cancer (PCa) have a limited ability to distinguish between benign and malignant disease. The ghrelin receptor has a differential expression in normal, benign and cancerous prostatic tissue. Targeting this receptor with 18F-radiolabelled peptidomimetics would enable differentiation between these disease states via PET imaging. A series of 19F-peptidomimetics were synthesized and characterized by HRMS, HPLC and 1 H-NMR spectroscopy in order to test locations for 18F radioisotope insertion. Competitive receptor binding assays using HEK293/GHS-R1a cells were used to evaluate compound binding affinities. This led to the identification of two lead compounds: [1-Nal4,Lys5(4-FB)]G-7039 (IC50 = 69 nM) …

Surface Functionalization And Bioconjugation Of Nanoparticles For Biomedical Applications, Longyan Chen

Electronic Thesis and Dissertation Repository

Colloidal inorganic nanoparticles (NPs) have been attracting considerable interest in biomedicine, from drug and gene delivery to imaging, sensing and diagnostics. It is essential to modify the surface of nanoparticles to have enhanced biocompatibility and functionality for the in vitro and in vivo applications, especially in delivering locally and recognizing biomolecules. Herein, the goal of this research work is to develop advanced NPs with well-tailored surface functionalities and/or bio-functionality for the applications in cell tracking and analytes detection.

In the first project, quantum dots incorporating with gelatin nanoparticles (QDs-GNPs) have been developed for bioimaging applications. Two different approaches have been …

A Molecular Simulation Study On Micelle Fragmentation And Wetting In Nano-Confined Channels, Mona Habibi

Electronic Thesis and Dissertation Repository

We performed coarse-grained molecular-dynamics (MD) simulations to study the structural and dynamical properties of surfactant micelles in equilibrium and under Poiseuille-like flow in a nano-confined geometry. We used the MARTINI force-field to model the interactions between water molecules, counter-ions, and sodium dodecyl sulfate (SDS) surfactants. SDS surfactant was chosen as the standard model because of its potential application in drug delivery systems. First, we focused on the self-assembly of SDS in equilibrium. To form stable spherical mi- celles, we ran simulations in the isothermal-isobaric ensemble (NPT) on a system of free SDS surfactants, counter-ions and water molecules. We studied the …