Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 178

Full-Text Articles in Physical Sciences and Mathematics

Analysis Of Additively Manufactured Inconel 718 Combustion Behavior In Promoted Oxygen Environments, Dominic George Dieguez May 2024

Analysis Of Additively Manufactured Inconel 718 Combustion Behavior In Promoted Oxygen Environments, Dominic George Dieguez

Open Access Theses & Dissertations

Promoted combustion testing is a vital tool for engineers to establish the combustion and flammability characteristics of materials (metallic or otherwise) in oxygen enriched environments. Historically, much of the established data for metallic promoted combustion has been with regards to materials in their cast and wrought forms. However, with the emergence of additive manufacturing as a preferred method of fabrication, the need exists to evaluate how metals in that form behave. Recent testing has demonstrated that even if a metal or alloy is nominally the same with regards to chemistry, flammability between samples in the wrought form can differ significantly …


Earth Abundant Catalyst For Evironmental Sustainability Applications, Javier Hernandez May 2024

Earth Abundant Catalyst For Evironmental Sustainability Applications, Javier Hernandez

Open Access Theses & Dissertations

The development of experimental methodologies for synthesizing a diverse range of metallic and metal oxide nanoparticles tailored for sustainable water treatment applications was investigated. These nanoparticles are prepared using environmentally friendly and scalable synthesis methods, underscoring their potential for large-scale production. Synthesized nanoparticles are harnessed for various processes, including catalysis and electrocatalysis, with a primary objective of degrading and removing organic pollutants from water. Key to this research is the encapsulation of nanoparticles within solid supports. Multiple methodologies are explored to engineer supports that ensure nanoparticle stabilization, monodispersion, and prevent unintended release into the environment. Two alternative approaches were evaluated …


Computational Study Of Fluorescent Molecular Probes For The Early Detection Of Alzheimer's Disease, Gabriela Elizabeth Molina Aguirre May 2024

Computational Study Of Fluorescent Molecular Probes For The Early Detection Of Alzheimer's Disease, Gabriela Elizabeth Molina Aguirre

Open Access Theses & Dissertations

Alzheimer's disease is a debilitating brain disorder that affects memory, thinking, and behavior. It is the most prevalent form of dementia and the seventh leading cause of death in the United States. As, researchers have identified biomarkers that can indicate the presence of the disease many years before the first symptoms appear, so there is an opportunity for early detection and treatment follow-ups, which could significantly improve the quality of life for those affected by this disease.This dissertation investigates the relationship between molecular structure and optical properties of donor-bridge-acceptor (DBA) fluorescent molecular probes designed for detecting Amyloid-β and p-Tau protein …


Combining Green Analytical Methods And Machine Learning To Develop Urinary Fatty Acid Models For Cancer Detection, Elizabeth Noriega Landa May 2024

Combining Green Analytical Methods And Machine Learning To Develop Urinary Fatty Acid Models For Cancer Detection, Elizabeth Noriega Landa

Open Access Theses & Dissertations

This study aimed to explore fatty acids (FAs) as non-invasive biomarkers for prostate cancer (PCa) detection and prognosis, and their potential applications in other cancers. The objectives of this study were: 1) Develop a non-invasive urinary FAs-based model for diagnosing PCa; 2) Develop a FAs-based liquid biopsy model for non-invasive monitoring of PCa progression; 3) Investigate FAs composition in periprostatic adipose tissue (PPAT) collected from PCa positive patients; 4) Investigate the potential of urinary FAs biomarkers for diagnosing clear cell renal cell carcinoma (ccRCC) and ovarian cancer (OC).For the PCa diagnostic model, urine samples from 334 biopsy-confirmed PCa-positive and 232 …


Synthesis Of Neoglycoproteins As Potential Biomarkers For Chagas Disease And Cutaneous Leishmaniasis Caused By Leishmania (Viannia) Braziliensis, Eileni Rodriguez Gil May 2024

Synthesis Of Neoglycoproteins As Potential Biomarkers For Chagas Disease And Cutaneous Leishmaniasis Caused By Leishmania (Viannia) Braziliensis, Eileni Rodriguez Gil

Open Access Theses & Dissertations

Protozoan parasites are responsible for causing numerous diseases in humans and mammals worldwide. Among them are Chagas disease (CD), caused by the parasite Trypanosoma cruzi (T. cruzi), and tegumentary leishmaniasis (TL), caused by the parasite Leishmania (Viannia). Both diseases coexist in many regions of Latin America, and current hurdles to differentially diagnose them and determine chemotherapy success need to be overcome. CD can be diagnosed by traditional serological tests and polymerase chain reaction (PCR), but disadvantages of these methods are that they may produce false negatives because the antigens used in commercial CD kits are not conserved across all T.cruzi …


Produced Water: Characterization And Treatment, Ramon Antonio Sanchez Rosario May 2024

Produced Water: Characterization And Treatment, Ramon Antonio Sanchez Rosario

Open Access Theses & Dissertations

In recent years, environmental concerns have urged companies in the energy sector to modify their industrial activities to facilitate greater environmental stewardship. For example, the practice of unconventional oil and gas extraction has drawn the ire of regulators and various environmental groups due to its reliance on millions of barrels of fresh water for hydraulic fracturing well stimulation, which is generally withdrawn from natural sources and public water supplies. Additionally, this process generates two substantial waste streams, which are collectively characterized as flowback and produced water. Whereas flowback water is comprised of various chemical additives that are used during hydraulic …


Selective Transfection Of A Transferrin Receptor-Expressing Cell Line With Dna-Lipid Nanoparticles And Synthesis Of Parasite-Derived Glycans As Biomarkers For Leishmaniasis, Irodiel Vinales Lozano May 2024

Selective Transfection Of A Transferrin Receptor-Expressing Cell Line With Dna-Lipid Nanoparticles And Synthesis Of Parasite-Derived Glycans As Biomarkers For Leishmaniasis, Irodiel Vinales Lozano

Open Access Theses & Dissertations

Despite notable progress in lipid nanoparticle (LNP)-mediated gene delivery, achieving selective transfection of specific cell types, such as cancer cells, remains a significant hurdle, hindering the advancement of innovative gene therapies. In this study, we engineered an LNP formulation encapsulating plasmid DNA (pDNA) encoding the monomeric Green Lantern (mGL) fluorescent reporter protein. The DT7 peptide ligand targeting human transferrin receptor 1 (hTfR1) was also conjugated to the LNP surface for targeted delivery to hTfR1-expressing cells. Optimization of LNP composition yielded favorable particle diameter, ζ-potential, yield, and pDNA encapsulation efficiency. Evaluation of transfection selectivity using a panel of two engineered cell …


Sterically Encumbering Ligands For The Synthesis And Stabilization Of Iron Nitride And Iron Oxo Compounds, Asiel Mena Dec 2023

Sterically Encumbering Ligands For The Synthesis And Stabilization Of Iron Nitride And Iron Oxo Compounds, Asiel Mena

Open Access Theses & Dissertations

The study of iron-nitrides has been found to be very attractive due to their potential role in processes like Haber-Bosch and nitrogen fixation by nitrogenase. The role of iron-nitrides in these processes is yet not well understood, and the fact that only handful of terminal iron-nitrides have been isolated or spectroscopically detected motivates us to study this type of systems, since much remains to be learned about the electronic and structural factors that affect the chemistry of the Feâ?¡N bond. Recently in our group, by using a super-bulky guanidinate ligand (LAr*), the obtention of an iron-nitride ([LAr*]FeN(py) (LAr* = (Ar*N)2C(NCtBu2), …


Computation-Assisted Molecular Discovery For Biomedical Applications: Seeking Small Molecules And Dna Sequences With High Affinity Target Binding, Payam Kelich Dec 2023

Computation-Assisted Molecular Discovery For Biomedical Applications: Seeking Small Molecules And Dna Sequences With High Affinity Target Binding, Payam Kelich

Open Access Theses & Dissertations

Binding affinity between two molecules is an essential property in drug and sensor discovery. Several computational and experimental methods exist to find molecules with high binding affinities to desired target molecules. These methods are often complementary, where fast computational methods can be used for the initial screening of molecules, and experimental methods can then screen and determine the molecules of interest and sometimes define the structures of bound complexes. After these steps, computational methods, like molecular dynamics (MD) simulations, can provide detailed insights into atomic interactions and binding, and machine learning approaches can analyze experiment-derived data to discern patterns and …


Green Analytical Methods For The Determination Of Perfluorocarboxylic Acids (Pfcas) And Fluorotelomer Alcohols (Ftohs) In Water, Ahsan Habib Dec 2023

Green Analytical Methods For The Determination Of Perfluorocarboxylic Acids (Pfcas) And Fluorotelomer Alcohols (Ftohs) In Water, Ahsan Habib

Open Access Theses & Dissertations

Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic organic compounds manufactured for their heat, water, and stain-resistant properties. PFAS can be found ubiquitously in the environment because they are widely used in everyday consumer products such as fast-food wrappers, non-stick cookware, stain-resistant products, cosmetics, aqueous film-forming foams, etc. As a result, PFAS are commonly detected in surface water, wastewater, and biosolids from wastewater treatment plants (WWTPs). These are the direct sources of PFAS contamination in drinking water supplies, which are substantial sources of human exposure. Among these PFAS chemicals, two major groups are perfluoroalkyl carboxylic acids (PFCAs) …


Study Of Human Circadian Protein (Hrory) And Lipid-Protein Interaction In Giant Virus (Pbcv-1), Laila Noor Dec 2023

Study Of Human Circadian Protein (Hrory) And Lipid-Protein Interaction In Giant Virus (Pbcv-1), Laila Noor

Open Access Theses & Dissertations

Project 1: Circadian rhythm is a 24-hour cycle that regulates physical and behavioral changes such as sleep-wake patterns in humans, tailoring the daily light and dark changes. Long-term disruption in circadian rhythms can cause sleep disorders such as sleep apnea, insomnia, et al. Limited research has been done on potential drugs to treat against circadian related sleep disorders. Inside the cell at molecular level, the circadian rhythm is regulated by interlocked time-delayed feedback loops, which involve positive and negative transcriptional regulators. Experimental results showed transcriptional factors Retinoic Acid Receptor-Related Orphan Receptors (RORs) improve the stability and functionality of the circadian …


Upcyclying Of Polyethylene Terephtalate By Addition Of Thermoplastic Elastomer, Diego Francisco Bermudez Dec 2023

Upcyclying Of Polyethylene Terephtalate By Addition Of Thermoplastic Elastomer, Diego Francisco Bermudez

Open Access Theses & Dissertations

Continual overconsumption of single-use plastics has generated challenges of solid waste management across the United States. Common plastic waste management solutions, such as landfill, have caused the migration of contaminants into the environment consequently affecting not only the health of wildlife, but also that of human beings. Alternative strategies for the handling of single-use plastic such as polyethylene terephthalate (PET), used in the food packaging industry, can ultimately help mitigate the noxious consequences of single-use plastics affecting entire ecosystems. This study demonstrates a potential avenue of materials upcycling by studying the effects of coupling PET with the thermoplastic elastomer styrene-ethylene-butylene-styrene …


Synthesis And Characterization Of Acetaminophen-Derived Nanoparticles: A Novel Approach To Inhibit Fibril Formation, Hannia Elena Mendoza-Dickey Dec 2023

Synthesis And Characterization Of Acetaminophen-Derived Nanoparticles: A Novel Approach To Inhibit Fibril Formation, Hannia Elena Mendoza-Dickey

Open Access Theses & Dissertations

In the realm of nanotechnology, nanoparticles (NPs), have garnered significant notoriety in recent scientific research due to their unique physical and chemical properties, such as fluorescence emissions, nanoscale dimensions (typically <1000 nm), ease of surface modification, and biocompatibility. Nanoparticles have shown their potential across a variety of areas, including advanced industrial applications and cutting-edge biomedical research. Considering their cost-effective synthesis, they have shown promise as therapeutic agents for a variety of bioimaging and biomedical applications. This thesis describes the synthesis and detailed analysis of acetaminophen-derived nanoparticles. Techniques such as Dynamic Light Scattering (DLS), Thioflavin T (THT) assay, Attenuated Total Reflectance Infrared Spectroscopy (ATR-IR), 1H NMR spectroscopy, and Ultraviolet-Visible Spectroscopy (UV-VIS) were utilized for structural and functional assessments. Acetaminophen derived nanoparticles (ANPs) exhibit potential to hinder the amyloidogenic conversion of soluble amyloid-forming proteins into their toxic form. The novelty of this research focuses on the utilization of chemical structures capable of traversing the Blood Brain Barrier (BBB) to mitigate xenotoxicant-induced neuronal damage, a notable contributor to neurodegenerative disorders. This thesis describes the synthesis and characterization of acetaminophen derived-nanoparticles (ANPs). Our nanoparticles possess anti-amyloidogenic properties as evidenced by their ability to disrupt in the soluble-to-toxic trajectory of HEWL. The prevalence and evolution of amyloid fibrils are consistent features in the pathology of neurodegenerative diseases such as Parkinson's disease (PD), Alzheimerâ??s Disease (AD), and Huntingtonâ??s Disease (HD), as well as metabolic disorders like Type 2 diabetes (T2D). The relationship between amyloidogenic pathways and these disorders highlights the imperative for enhanced understanding and the formulation of specific therapeutic interventions.


A Noninvasive Urine-Based Method For Kidney Cancer Early Detection, Kiana Holbrook Dec 2023

A Noninvasive Urine-Based Method For Kidney Cancer Early Detection, Kiana Holbrook

Open Access Theses & Dissertations

Based on the traditional serological uses to obtain diagnoses of cancer and biopsy techniques, common cancer detection could be not only invasive but expensive and some tests are also unreliable. Currently, urine is one of the most frequently used and collected specimens in the clinical diagnoses. While the areas of urinalysis and metabolomic profiling has received interest in the top clinical research, there are limited components to the validity, specificity, as well as sensitivity of endogenous urine substrates to detect early stages of cancers. Although there is research showcasing that urine is impacted by age, cancer type, geographical location, and …


Inkjet-Printed Electrochemical Sensors For Lead Detection, Annatoma Arif Aug 2023

Inkjet-Printed Electrochemical Sensors For Lead Detection, Annatoma Arif

Open Access Theses & Dissertations

This PhD dissertation research has developed a simple, miniaturized, sensitive, selective, reproducible, and disposable 3D (inkjet printed – additive manufacturing technology) gold (Au) plated electrochemical sensor (ECS) on shape memory polymer (SMP) for aqueous lead detection. This technology has shown promising performance in the application of electrochemical sensing (lead (II) detection) due to increased effective electrode surface area (7.25 mm^2 ± 0.15 mm^2) despite miniaturizing lateral surface area (4.19 mm^2). The design, fabrication processes, optimization including bismuth functionalization, evaluation, uncertainty analysis, and cost analysis of the novel SMP based inkjet printed Au plated sensor have been delineated in this manuscript …


A Dft Analysis And Simple Hamiltonian Modeling Of A Molecular System Employed For Experimental Evidence Of Quantum Teleportation, Pedro Ulises Medina Gonzalez Aug 2023

A Dft Analysis And Simple Hamiltonian Modeling Of A Molecular System Employed For Experimental Evidence Of Quantum Teleportation, Pedro Ulises Medina Gonzalez

Open Access Theses & Dissertations

Radical ion pairs (RIPs) have been used to demonstrate quantum teleportation in molecular systems for applications in quantum information science. Covalent organic donor-acceptor (D-A) molecules can produce RIPs through photo-induced charge transfer and an additional radical (R) molecule makes quantum teleportation possible. We present the electronic structure and analyze charge transfer excited states of a recently studied [1] D-A-R molecular system using density functional theory. The distances between donor-acceptor and donor-radical are about 12.9 \AA $\,$ and 21.9 \AA, respectively. The excitation energies are calculated using the perturbative delta-SCF method and agree with other conventional excited-state methods and experimental reference …


Removal Of Nonylphenols From Water And Wastewater Using Alginate-Activated Carbon Beads, Angelica Araly Chacon Aug 2023

Removal Of Nonylphenols From Water And Wastewater Using Alginate-Activated Carbon Beads, Angelica Araly Chacon

Open Access Theses & Dissertations

The presence of contaminants of emerging concern (CECs) have been affecting water quality in recent years. The United States Environmental Protection Agency (U.S EPA) defines CECs as toxic chemicals without regulatory status and with adversely impact on the wildlife and people. Among the CECs, nonylphenols (NPs) are frequently found in all water systems and are categorized as endocrine-disrupting compounds (EDCs) due to their ability to mimic hormones causing reproductive and developmental effects in humans and animals. The main sources of discharge and distribution of NPs into the environment are wastewater treatment plants (WWTPs) which are not designed to remove them. …


Electrochemical Approaches To Life-Support Resources In Space Missions And Nuclear Technologies: Hydrogen Peroxide And Uranium Films, Armando Manuel Pena-Duarte Aug 2023

Electrochemical Approaches To Life-Support Resources In Space Missions And Nuclear Technologies: Hydrogen Peroxide And Uranium Films, Armando Manuel Pena-Duarte

Open Access Theses & Dissertations

Space race has developed several technological advances that have achieved and continue to achieve the success of space missions in the aerospace timeline. Currently, the number of space technical and scientific innovations is still growing––demanding new materials and developments for extreme performing applications of fuel cells, batteries, supercapacitors, and systems of nuclear energy. Space missions require life-support solutions, auto-sustainable closed-loop living environments, cleaning and sanitizing solutions against pathogens, and safe nuclear-based resources of energy––with fissile materials with well-controlled dimensions within the core fuel elements. Likewise, to guarantee safety conditions, reduce costs, and facilitate operational logistics, space missions must reduce their …


Advances In One-Electron Self-Interaction-Correction Methods For Accurate And Efficient Self-Interaction-Free Density Functional Calculations, Selim Romero Aug 2023

Advances In One-Electron Self-Interaction-Correction Methods For Accurate And Efficient Self-Interaction-Free Density Functional Calculations, Selim Romero

Open Access Theses & Dissertations

Density functional theory (DFT) is a widely used computational method for studying electronic structures of atoms, molecules, and solids. It provides an exact theory for obtaining ground state energy from the ground state density. However, since the exact exchange-correlation functional remains unknown, approximate exchange-correlation functionals called approximate density approximations (DFAs) are used. The foundation of many DFAs is the local spin density approximation (LSDA). It serves as the starting point for constructing various DFAs. However, DFAs are prone to self-interaction errors (SIE) due to the improper cancellation of the approximate exchange energy and the Coulomb energy. This issue impacts the …


Developing And Applying Computational Methods On Biomolecules, Shengjie Sun May 2023

Developing And Applying Computational Methods On Biomolecules, Shengjie Sun

Open Access Theses & Dissertations

Computational biophysics is an interdisciplinary subject that uses numerical algorithms to study the physical principles underlying biological phenomena and processes. Electrostatic interactions play an important role in computational molecular biophysics and their potential impact on disease mechanisms. At distances larger than several Angstroms, electrostatic interactions dominate all other forces, while the alteration of short-range electrostatic pairwise interactions can also have significant effects. The dual nature of electrostatic interactions, being dominant at long-range and specific at short-range, underscores their profound implications for wild-type structure and function. Any disruption of the complex electrostatic network of interactions may abolish wild-type functionality and could …


Structure Study Of Small Heat Shock Protein 27, Zhaobo Li May 2023

Structure Study Of Small Heat Shock Protein 27, Zhaobo Li

Open Access Theses & Dissertations

Molecular chaperones are a class of oligomeric proteins that play a critical role inpreventing the aggregation of non-native protein so that these proteins can later be refolded. Chaperones are ubiquitously expressed in all the kingdoms of life where their function is to counteract cellular stress and to maintain protein homeostasis. One subgroup of molecular chaperones is characterized by low molecular weight and are termed small heat shock proteins. The focus of the proposed research is the small heat shock protein 27 (Hsp27). Hsp27 is an ATP independent chaperone that is overexpressed in response to heat shock, radiation damage, oxidative damage, …


Novel Pathways To Tailor Charge And Spin In Materials And Investigating The Impact On Sensing And Electrochemical Energy Applications, Aruna Narayanan Nair May 2023

Novel Pathways To Tailor Charge And Spin In Materials And Investigating The Impact On Sensing And Electrochemical Energy Applications, Aruna Narayanan Nair

Open Access Theses & Dissertations

Catalysis is integral to our daily lives, as it streamlines and accelerates numerous chemical reactions essential for producing various materials, fuels, and chemicals. With the rising demand for clean, sustainable energy sources, optimizing catalytic materials and processes becomes increasingly vital. In the realm of renewable energy production, catalysis is crucial for efficiently converting energy from sustainable resources, such as solar, wind, and biomass, into chemical energy stored in fuels or directly into electrical energy.The electronic charge distribution in materials significantly influences their physical and chemical properties, facilitating the development of advanced electronic, optoelectronic, sensing, and energy conversion devices. Since catalysis …


Achieving Safe Use Of Advanced Materials In Drinking Water Through Novel Nano Analytics And Enabling Electrification Using Green Catalyst, Kenneth Ray Flores Dec 2022

Achieving Safe Use Of Advanced Materials In Drinking Water Through Novel Nano Analytics And Enabling Electrification Using Green Catalyst, Kenneth Ray Flores

Open Access Theses & Dissertations

The accumulation of engineered nanomaterials (ENMs) in environmental sectors will continue to increase as more applications are discovered for their unique properties and characteristics. Additionally, the presence of nanomaterials in the environment becomes exacerbated as more consumer products containing nanoparticles are approved for use. It is debated whether the toxic effects of nanoparticles stem from the particles themselves, ionic species, or formation of secondary particles. Therefore, understanding the behavior of nanoparticles in the environment becomes key to discerning the toxicological effects of nanoparticles. Many advancements have been made with ICP-MS to understand the behavior of nanoparticles in the environmental systems, …


Nano-Engineered Soft Magnets: Potential Application In Water Treatment, Hyperthermia And Molecular (Organic) Magnets, Yohannes Weldemariam Getahun Dec 2022

Nano-Engineered Soft Magnets: Potential Application In Water Treatment, Hyperthermia And Molecular (Organic) Magnets, Yohannes Weldemariam Getahun

Open Access Theses & Dissertations

Scrutinizing the remarkable and tunable properties of magnetic materials at a nanoscale size "There's Plenty of Room at the Bottom..." Richard Feynman, this study attempts to find sustainable solutions to some of the deteriorating environmental, health, and energy problems the world is encountering. Due to their simple preparation, surface adaptability, and tunable magnetic and optical properties, magnetic nanoparticles have been extensively investigated in water treatment, cancer therapy, data storage, and more. However, relying on non-reusable and chemical-based treatment agents in water, complex and costly cancer treatment procedures and molecular magnets that operate far below room temperature limited those attempts from …


Molecularly Inspired Organic Macrocycles Catalyzed Water Splitting Reaction For Sustainable Fuel Production, Yulu Ge Dec 2022

Molecularly Inspired Organic Macrocycles Catalyzed Water Splitting Reaction For Sustainable Fuel Production, Yulu Ge

Open Access Theses & Dissertations

Hydrogen fuel generation through electrochemical water splitting is considered as an advanced energy conversion technology driven by sustainable energy. High activity and cost effective electrocatalysts that are able to drive down the energy cost needed for both two half reactions, namely, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are required to fulfill the energy transfer process. Exploring new electrocatalysts with enhanced OER and HER activity and stability is crucial for renewable energy applications. Porphyrin and macrocycle derivatives are versatile and can electrochemically catalyze water splitting efficiently. In our work, we use porphyrin as platform for both HER and …


Rational Design Of Precisely Tailored Electrocatalysts For Efficient And Durable Electrocatalytic Devices, Mohmed Sanad Noufal Dec 2022

Rational Design Of Precisely Tailored Electrocatalysts For Efficient And Durable Electrocatalytic Devices, Mohmed Sanad Noufal

Open Access Theses & Dissertations

Due to their superior conversion efficiency, high power density, and green nature, sustainable energy technologies such as Fuel cells and Zinc-air batteries, once installed to produce green hydrogen fuel as well as energy storage devices, are expected to play an essential role in reducing the environmental effect of human transportation by replacing fossil fuels. However, the current bottleneck for the low-temperature polymer membrane fuel cells that dominate the fuel cell vehicle market is the sluggish kinetics of the oxygen reduction reaction (ORR) at the cathode. The slow ORR kinetics significantly reduce the efficiency of chemical-electrical energy conversion. Similarly, hydrogen production …


Direct Ink Write And Thermomechanical Characterization Of Thermoset Composites, Sergio Dante Favela Dec 2022

Direct Ink Write And Thermomechanical Characterization Of Thermoset Composites, Sergio Dante Favela

Open Access Theses & Dissertations

This research will be divided into two sections. The first section discusses direct ink writing and thermomechanical characterization for thermoset composites. The thermoset ink is prepared with fillers aiding the printing process by modifying the rheology of the ink and geometry retention by allowing for the part to have an initial UV cure step. Three specimen formulations with different weight percentages were printed by material extrusion in the shape of tensile specimens following ASTM standard D638 to characterize the mechanical properties at room temperature, 100â?? and 200â??. Furthermore, the ink resin was characterized through DSC, TGA, and rheology testing. The …


Synthesis, Characterization, And Reactivity Studies Of Highly Reduced Early-Metal Complexes Supported By Imidazolin-2-Iminato Ligands, Maria Alejandra Gomez Torres Aug 2022

Synthesis, Characterization, And Reactivity Studies Of Highly Reduced Early-Metal Complexes Supported By Imidazolin-2-Iminato Ligands, Maria Alejandra Gomez Torres

Open Access Theses & Dissertations

Our group has shown that reduction of titanium complexes supported by the sterically encumbering N-donor ligands 1,3â??bis(Dipp)imidazolinâ??2â??iminato (ImDippNâ??) and ketimine guanidinate (ketGuan = [(tBuC=N)C(NDipp)2]-) gives access to electron rich platforms featuring a metal coordinated, reduced, dearomatized arene substituent, which act as an electronic reservoir capable of facilitating multi-electron transfer chemistry driven by the rearomatization driving force. For instance, the arene-masked Ti(II) synthon (DippketGuan)(η6-ImDippN)Ti (Dipp = 2,6-iPr2C6H3) (TiDipp) is a versatile and potent one- and two-electron reductant capable of distinctive late-metal type reactivity such as transfer hydrogenation and catalytic olefin hydrogenation. Interestingly, TiDipp can mediate the reversible cleavage of thiophene and, …


Variations In Copper Form Exposure Differentially Modulate Zea Mays (Corn) Physiological Responses, Carolina Valdes Bracamontes Aug 2022

Variations In Copper Form Exposure Differentially Modulate Zea Mays (Corn) Physiological Responses, Carolina Valdes Bracamontes

Open Access Theses & Dissertations

In the present study, Zea mays seedlings grown under nano Cu(OH)2 (nCu), bulk Cu(OH)2 (bCu), and ionic CuSO4 (iCu) compound exposure were harvested after six days. The nutritional profile was determined to be significantly disrupted in the roots by 1000 ppm bCu treatment, resulting in a 58.7% reduction in potassium compared to the control. In the shoots, a significant decrease of manganese was observed for 10 and 1000 ppm iCu treatments with 55.7% and 64.2% reductions, respectively. The overall protein content and catalase (CAT) enzymatic activity, however, remained unaffected in either roots or shoots, while an absence of polyphenol oxidase …


Exposure Of Candyland Red Tomatoes (¬Solanum Lycopersicum L.) To Various Metal Oxide Nanomaterials: Full Life Cycle And Assessment Of Fruit Quality, Jesus Manuel Cantu Aug 2022

Exposure Of Candyland Red Tomatoes (¬Solanum Lycopersicum L.) To Various Metal Oxide Nanomaterials: Full Life Cycle And Assessment Of Fruit Quality, Jesus Manuel Cantu

Open Access Theses & Dissertations

The use of nanotechnology in agriculture has attained high interest to enhance crop production due to their unique properties. Moreover, metal oxide nanomaterials can potentially supplement nutrients, enhance plant growth, and crop production. When investigating fruits' nutritional quality, carbohydrates and phytonutrients (bioactive compounds) play important roles. Therefore, it is important to understand how nanomaterials will affect the quality of tomato fruits. In this dissertation, various metal oxides were synthesized and applied to Candyland Red tomato seedlings to assess the plant growth and tomato production. In the first investigation, Candyland Red tomatoes (Solanum lycopersicum) were exposed to synthesized pristine CuO and …