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Effects Of Ecologically Relevant Concentrations Of Nitrate On Behavior In Betta Splendens, Sarah Janson May 2024

Effects Of Ecologically Relevant Concentrations Of Nitrate On Behavior In Betta Splendens, Sarah Janson

Honors College

Nitrate is a ubiquitous pollutant that is becoming more prevalent in both fresh and saltwater environments. Short term effects are often studied, but an organism’s response to stress can change due to whatever the stressor is. In order to research this, a study was run using environmentally relevant nitrate treatments (0 mg/L, 10 mg/L NO3-N, and 100 mg/L NO3-N) to see the effect of nitrate on scototaxis behaviors, a measure of anxiety. This study used Betta splendens because they are easy to rear and have very well documented behaviors. In addition to the scototaxis, the effect of temperature on mortality …


Using Cdom Optical Properties To Estimate Its Source, Distribution, And Doc Conentration In Maine Estuaries, Camille Michaud May 2024

Using Cdom Optical Properties To Estimate Its Source, Distribution, And Doc Conentration In Maine Estuaries, Camille Michaud

Honors College

Colored dissolved organic matter (CDOM) contributes largely to ocean color, and therefore, influences processes and applications that interact with light in the ocean such as remote sensing and biogeochemistry. It is a component part of dissolved organic carbon (DOC) and there is a strong relationship in coastal waters between CDOM absorption and DOC concentration. CDOM optical properties also vary with salinity and source. These important aspects of CDOM absorption led us to collect CDOM samples across the salinity gradients of 3 estuaries in Maine: the Penobscot, Damariscotta, and Sheepscot. We sampled stations along the salinity gradient in each estuary from …


Development Of Novel Immobilized Copper–Ligand Complex For Click Chemistry Of Biomolecules, Rene Kandler, Yomal Benaragama, Manoranjan Bera, Caroline Wang, Rasheda Aktar Samiha, W.M.C. Sameera, Samir Das, Arundhati Nag May 2024

Development Of Novel Immobilized Copper–Ligand Complex For Click Chemistry Of Biomolecules, Rene Kandler, Yomal Benaragama, Manoranjan Bera, Caroline Wang, Rasheda Aktar Samiha, W.M.C. Sameera, Samir Das, Arundhati Nag

Chemistry

Copper-catalyzed azide–alkyne cycloaddition click (CuAAC) reaction is widely used to synthesize drug candidates and other biomolecule classes. Homogeneous catalysts, which consist of copper coordinated to a ligand framework, have been optimized for high yield and specificity of the CuAAC reaction, but CuAAC reaction with these catalysts requires the addition of a reducing agent and basic conditions, which can complicate some of the desired syntheses. Additionally, removing copper from the synthesized CuAAC-containing biomolecule is necessary for biological applications but inconvenient and requires additional purification steps. We describe here the design and synthesis of a PNN-type pincer ligand complex with copper (I) …


A Conceptual Understanding Of Concepts In Organic Chemistry, Timerra Chisham May 2024

A Conceptual Understanding Of Concepts In Organic Chemistry, Timerra Chisham

Theses/Capstones/Creative Projects

As students continue to make the transfer into organic chemistry from general chemistry, they will have to adjust to the new type of thinking required so that they will not fall behind in understanding material and will have success in the course. For this research project, I explored which concepts taught in organic chemistry are the most difficult for students to grasp. I had two main goals for this project. The first one is the central idea that I focused on, which was to see which concepts that have been taught in Organic Chemistry 1 the students are most confident …


The Effects Of Free Volume And Processing On The Development Of Gas Separation Membranes, Jacob Schekman May 2024

The Effects Of Free Volume And Processing On The Development Of Gas Separation Membranes, Jacob Schekman

Dissertations

Structure, thermal, mechanical, gas transport, and free volume properties of thiol-ene based systems are investigated and discussed. In the pursuit of generating low energy-cost polymer membranes for gas separation, it became apparent that UV-curing of thiol-ene materials presented several routes toward achieving this goal. Network structure plays a vital role in determining the gas transport properties of membrane materials. UV photopolymerization techniques provide a means to rapidly vitrify network morphologies which can be tuned depending on choice of monomer. Thiol-ene monomers offer a broad range of precursor materials from which to choose for the design of functional membrane materials.

Chapter …


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 …


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 …


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 …


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 …


Ecological Effects And Ethics Of A Species Range Shift To High Elevation Ponds, Ava Ardito May 2024

Ecological Effects And Ethics Of A Species Range Shift To High Elevation Ponds, Ava Ardito

Honors College

As temperatures warm, the climate crisis is having a significant influence on species across the world and altering their distributions. Colorado's high elevation ponds have recently observed a species range shift, traveling to higher altitudes than they have previously inhabited. The Mexican Cut Nature Preserve near the Rocky Mountain Biological Laboratory (RMBL) in Gothic, CO, is home to a prominent caddisfly Limnephilus externus, but recently a new range-shifting species, Nemotaulius hostilis, has appeared. Caddisflies play an essential role in nutrient cycling and putting energy back into the food web. The range-shifting species is known to excrete high rates of phosphorus …


Evaluating The Accuracy Of Different Remote Sensing Methods Used To Derive Absorption From Chromophoric Dissolved Organic Matter In Maine Estuaries, Andrea Rudai May 2024

Evaluating The Accuracy Of Different Remote Sensing Methods Used To Derive Absorption From Chromophoric Dissolved Organic Matter In Maine Estuaries, Andrea Rudai

Honors College

Current knowledge of dissolved organic carbon (DOC) in Maine estuaries is based on limited field research. By using chromophoric dissolved organic matter (CDOM) as a proxy, it is possible to use satellite images to estimate the concentration of DOC in an entire body of water. This study aims to evaluate different methods that calculate absorption by CDOM from ocean color remote sensing using images taken by Landsat 9 of the Sheepscot, Penobscot, and Damariscotta rivers. The study revealed that although there were some similarities in along-estuary trends between the remotely- sensed absorption and absorption measured in situ, the algorithms that …


Engineering Multifunctional Silicon Nanostructures From Biorenewable Cellulose Nanocrystals, Nancy Chen May 2024

Engineering Multifunctional Silicon Nanostructures From Biorenewable Cellulose Nanocrystals, Nancy Chen

All Dissertations

The imperative search for alternative materials to address the pressing demand for advance energy storage is underscored by the escalating environmental predicaments. Lithium-ion batteries (LIBs) with graphite anodes have become the benchmark in energy storage; however, they are approaching a saturation point in terms of energy density. Silicon emerges as a promising contender to supplant graphite, owing to its profuse availability, cost-effectiveness, and impressive specific capacity of 4200 mAh g-1. By integrating silicon anodes, LIBs stand to undergo a radical transformation, markedly diminishing in weight and size, thus heralding a novel wave of compact, lightweight energy storage systems. …


Carbon "Quantum" Dots: Structures, Properties, And Issues, Weixiong Liang May 2024

Carbon "Quantum" Dots: Structures, Properties, And Issues, Weixiong Liang

All Dissertations

Carbon dots (CDots) are small carbon nanoparticles (CNPs) with effective surface passivation. The effective passivation has been achieved by the surface functionalization of pre-existing CNPs with organic molecules, mostly molecules containing primary or secondary amine moieties. In the studies highlighted in this dissertation, CNPs were functionalized by selected organic molecules, including especially the use of radical addition reactions, to generate CDots with strong absorption and bright fluorescence emissions. A good demonstration of the approach was the N-ethylcarbazole (NEC) radical addition to CNPs under microwave irradiation. Spectroscopy and microscopy methods were employed to characterize the resulting NEC-CDots, and the results …


Investigation Of Magnetic, Spectroscopic, And Structural Properties Of Molecular Metal Compounds, Alexandria Bone May 2024

Investigation Of Magnetic, Spectroscopic, And Structural Properties Of Molecular Metal Compounds, Alexandria Bone

Doctoral Dissertations

Compounds exhibiting single-molecule magnetism (SMM) are of current interest for potential use in molecular data storage and quantum computing applications. However, rapid magnetic relaxation at desired operating temperatures currently limits the use of these materials, and a more thorough understanding of the magnetic and vibrational transitions that affect magnetic memory is required to inform SMM design. The primary focus of this dissertation is the study of magnetic and vibrational modes in molecular magnetic compounds via advanced spectroscopic techniques such as inelastic neutron scattering (INS), far-IR magneto-spectroscopy (FIRMS), and high-field, high-frequency electron paramagnetic resonance (HFEPR) to directly observe transitions among zero-field …


Investigating Small Molecule Behavior In Living Bacterial Membranes With Second Harmonic Scattering, Marea J. Blake May 2024

Investigating Small Molecule Behavior In Living Bacterial Membranes With Second Harmonic Scattering, Marea J. Blake

Doctoral Dissertations

A molecule's entry into a cell is impeded primarily at the surface of Gram-positive bacteria. This interface serves as the boundary separating cellular contents from the external environment and is composed of a thick layer of peptidoglycan and a lipid bilayer equipped with protein and lipid species with various roles including that of small-molecule transport. As such, understanding these molecule-membrane interactions is imperative to examine in order to design novel drugs or adjuvants to combat the global antibiotic resistance predicament. Knowledge regarding passive diffusion and overall organization of small molecules in the lipid bilayer of living Gram-positive cells is limited …


Biotinylated Protein Capture And Tween-20 Assisted Exosome Isolations Via Capillary Chanelled Polymer Fiber, Md Khalid Bin Islam May 2024

Biotinylated Protein Capture And Tween-20 Assisted Exosome Isolations Via Capillary Chanelled Polymer Fiber, Md Khalid Bin Islam

All Theses

In the past two decades, Marcus and colleagues have led the advancement of capillary-channeled polymer (C-CP) fiber stationary phases for biomacromolecule separations, including proteins and nanovesicles. These stationary phases offer notable advantages, including low cost ($5/column), straightforward column fabrication, and the capacity for on-column surface modification, enabling high chemical selectivity. This study examines a C-CP fiber modification strategy for capturing target proteins and develops a Tween-20-assisted C-CP-based hydrophobic interaction chromatography (HIC) method for the isolation and quantification of exosomes from human urine.

The quest for higher-throughput and cost-effective protein isolation techniques remains a key focus in a variety of end …


Synthesis And Characterization Of Indole-Based Zinc Dipyrrin Photosensitizers, Jean-Pierre Sanza May 2024

Synthesis And Characterization Of Indole-Based Zinc Dipyrrin Photosensitizers, Jean-Pierre Sanza

Electronic Theses and Dissertations

Metal complexes of dipyrromethene (dipyrrins) used as sensitizers in photocatalysis offer a way to harness solar energy in chemical bonds to create new fuels. This offers the dual role of reducing fossil fuel dependence and atmospheric CO2 levels. Traditionally, metal dipyrrin complexes are synthesized using substituted pyrroles, aldehydes, and transition metals. Indoles have a more expanded pi-electron system and their dipyrrin-type complex may exhibit visible light absorption, suggesting that they can act as photosensitizers for CO2 reduction processes. A novel indoledipyrromethene was synthesized using unsubstituted indole and mesitaldehyde. The complex exhibits visible light absorption at 422 nm. Its …


3d-Printed Microfluidic Devices For Electrochemiluminescence Detection Of Mirna, Oscar Clement May 2024

3d-Printed Microfluidic Devices For Electrochemiluminescence Detection Of Mirna, Oscar Clement

Honors Scholar Theses

This thesis outlines the research conducted over the past two years on the production and application of microfluidic devices (MFDs) in electrochemiluminescent-based bioanalytical assays. The work is categorized into two main projects: designing and manufacturing MFDs and developing electrochemiluminescent (ECL) assays for detecting Alzheimer's disease (AD) associated microRNAs (miRNAs) using CRISPR technology. The process of learning to design MFDs involved acquiring proficiency in computer-aided design (CAD) software, stereolithography (SLA) 3D printing, and iterative design techniques. The development of the ECL-based assay for AD miRNA was a multidisciplinary endeavor, combining elements of inorganic and biological chemistry. Although the research on the …


Optimization Of Xrf Experimental Protocol For Bruker Picofox, Tyler Ashcraft May 2024

Optimization Of Xrf Experimental Protocol For Bruker Picofox, Tyler Ashcraft

Undergraduate Honors Theses

The research performed was to improve the precision and accuracy of sample measurements made with the Bruker Picofox X-ray fluorescence spectrometer. The initial method of sample preparation using a 10 μL drop spotted onto an acrylic plate and then drying in an oven at 80˚C produced inconsistent results even when processing replicates or the same sample multiples times. Multiple experiments were conducted to determine the effects of different sample preparation conditions on the resulting accuracy. The conditions tested were drop size, plate composition, and drying temperature. For each experiment an internal standard (gallium) was used at concentrations similar to that …


Synthesis Of Thermoresponsive Poly(N-Isopropyl Acrylamide) Based Core-Shell And Hollow Shell Nanogel With Tunable Core And Shell Thickness, Mohamad Hijazi, Molla R. Islam May 2024

Synthesis Of Thermoresponsive Poly(N-Isopropyl Acrylamide) Based Core-Shell And Hollow Shell Nanogel With Tunable Core And Shell Thickness, Mohamad Hijazi, Molla R. Islam

Student Scholar Symposium Abstracts and Posters

Nanogels have emerged as a notably safer and more effective means for drug delivery, primarily due to their adjustable drug-loading capabilities. Hollow-core nanoparticles offer some unique properties that are desirable for drug delivery applications. Initially, silica core nanoparticles were synthesized using the Stöber process at different temperatures where Tetraethoxysilane (TEOS) undergoes hydrolysis in the presence of ethanol and then a condensation reaction to form silica nanoparticles. Scanning Electron Microscopy (SEM) and Optical Microscopy (OM) analysis revealed that the size of silica core particles varied with the synthesis temperature (300 nm at 30°C to 150 at 60°C). The core silica particles …


Electrochemical Modulation Of Surface Plasmon Wave To Investigate Dna-Based Sensing Platforms And Detection Of Sars-Cov2., Anil Sharma May 2024

Electrochemical Modulation Of Surface Plasmon Wave To Investigate Dna-Based Sensing Platforms And Detection Of Sars-Cov2., Anil Sharma

Electronic Theses and Dissertations

This study offers a thorough comparative analysis of optical and electrical signaling strategies for assessing the electrochemical properties of different redox-labeled DNA-based biosensing platforms. In addition, it illustrates the development of an optical interrogation technique with electrochemical modulation of surface plasmon waves (ECM-SPW) as a route for analyzing and implementing DNA-based hybridization sensors. For those quantitative analyses, we chose a model sensing platform composed of a methylene blue (MB)-modified single-stranded DNA (ssDNA) signaling probe and an unlabeled capture ssDNA probe that complements the signaling probe. Two types of signaling probes were employed in this work: one with MB attached to …


Using Ion Mobility Mass Spectrometry In Conjuction With Derivatization Methods To Enhance The Separation Of Different Steroid Isomers, Shadrack Lucas May 2024

Using Ion Mobility Mass Spectrometry In Conjuction With Derivatization Methods To Enhance The Separation Of Different Steroid Isomers, Shadrack Lucas

All Theses

One of the major problems facing analytical chemistry challenge is the isomers separation, due to their closely related molecular structures and physicochemical properties. Therefore, in this thesis, we have performed the separation of steroid isomers through the use of ion mobility mass spectrometry, using various chemical approaches. Ion mobility is an effective high-resolution separation techniques that utilizes the mobility of ions in the gas-phase environment. A useful tool for isomeric analysis due to the ability to separate different isomeric classes of steroids according to their varied collision cross-sections, which is achieved by taking advantage of differences in ion mobility.

Moreover, …


Development Of An Enhanced Sampling Workflow To Accelerate Molecular Docking With Sparse Biophysical Information, Zachary Stichter May 2024

Development Of An Enhanced Sampling Workflow To Accelerate Molecular Docking With Sparse Biophysical Information, Zachary Stichter

Masters Theses & Specialist Projects

Rapid docking of flexible biological macromolecules remains a significant open challenge in protein structure determination. While rigid docking is relatively simple with toolkits such as TagDock, a key obstacle to rapid flexible docking is the complexity and roughness of the free energy surface associated with protein conformational motion (often termed the many-minima problem), meaning conventional molecular dynamics methods do not effectively sample protein conformations near the interaction complex in accessible timescales. Methods such as metadynamics and replica exchange molecular dynamics exist to ameliorate this obstacle, yet these methods use nonphysical biases or random swaps to enhance sampling. In contrast, high …


Process Modeling The Neuroprotective Effects Of A Plant-Based Diet On Parkinson's Disease, Julia Mitchell May 2024

Process Modeling The Neuroprotective Effects Of A Plant-Based Diet On Parkinson's Disease, Julia Mitchell

Undergraduate Honors Theses

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor symptoms such as tremors, bradykinesia, rigidity, and postural instability. Recent research suggests an avenue for potential neuroprotection through dietary intervention, specifically the adoption of a plant-based diet. A plant-based diet predominantly comprises foods derived from plants, emphasizing fruits, vegetables, grains, legumes, and nuts while minimizing or excluding animal products. This thesis aims to explore the biochemical pathways implicated in PD progression and the potential impact of dietary choices on these pathways. The investigation focuses on several key pathways: alpha-synuclein aggregation, the blood-brain barrier crossing of levodopa, oxidative stress, ferroptosis, …


Sustainable Methodologies For Synthesis Of Small Organic Molecules Using Micellar Catalysis., Deborah Sam Ogulu May 2024

Sustainable Methodologies For Synthesis Of Small Organic Molecules Using Micellar Catalysis., Deborah Sam Ogulu

Electronic Theses and Dissertations

Organic synthesis is a critical process in the creation of small molecule pharmaceuticals and agrochemicals. However, most methods for synthesizing these small molecules rely on toxic organic solvents as the reaction medium which account for approximately 80% of pharmaceutical waste. Moreover, many catalytic reactions require expensive endangered precious metals like palladium and costly metals. This dissertation presents research that aims to develop sustainable, eco-friendly reaction conditions to address these issues. We developed a ligand-free bimetallic nanocatalyst for the hydrogenation of unsaturated enones. This ligand-free nanocatalyst was prepared from nickel and ppm loading of palladium and was stabilized by harnessing the …


Ligand-Stabilized Sno2 As A High-Performance And Scalable Electron Transport Material For Inverted Perovskite Solar Cells., Sashil Chapagain May 2024

Ligand-Stabilized Sno2 As A High-Performance And Scalable Electron Transport Material For Inverted Perovskite Solar Cells., Sashil Chapagain

Electronic Theses and Dissertations

Over the past decade, perovskite solar cell (PSC) technology has attracted significant attention for its low material costs, simple fabrication processes, and impressive photovoltaic performance, with recent power conversion efficiencies (PCEs) surpassing 26%. This advancement marks PSCs as strong competitors to traditional silicon-based photovoltaics. Despite the high efficiency of PSCs, the path to commercialization is hindered by challenges in stability, scalability, and module efficiency. The stability and scalability of PSCs are primarily dependent on the successive charge transfer layers (CTLs) that are interfaced with the perovskite layer. Among CTLs, metal oxide (MOx) CTLs are preferred for their cost-effectiveness, …


Utilizing Metal Ligand Cooperativity To Activate Small Molecules., Christine Burgan May 2024

Utilizing Metal Ligand Cooperativity To Activate Small Molecules., Christine Burgan

Electronic Theses and Dissertations

The problems created from the excessive use of fossil fuels can be approached from two directions: capture the CO2 from the atmosphere or develop alternative energy sources. The current industrial standards for these are environmental and/or health hazards and utilize precious metals, respectively. Metal ligand cooperativity (MLC) has emerged as a promising alternative to using precious metals to activate small molecules. In this dissertation, we focus on a series of metal complexes based on the ligand diacetyl-2-(4-methyl-thiosemicarbazone)-3-(2-hydrazinopyridine) (H2L1) for either hydrogen evolution or CO2 capture. The novel complexes were characterized by 1H NMR, …


Electrocatalytic Degradation Of Bisphenol A Using Nickel Sulfide Supported On Graphene Oxide And Cobalt Sulfide Supported On Graphene Oxide Composite Materials, Katherine Ellynn Wright May 2024

Electrocatalytic Degradation Of Bisphenol A Using Nickel Sulfide Supported On Graphene Oxide And Cobalt Sulfide Supported On Graphene Oxide Composite Materials, Katherine Ellynn Wright

Theses and Dissertations

The degradation of bisphenol A (BPA) by nickel sulfide supported on graphene oxide (NiS/GO) and cobalt sulfide supported on graphene oxide (CoS/GO) composite materials was investigated. The catalysts were studied to determine the optimal conditions for BPA degradation using electrocatalysis. Electrocatalytic trials were performed using varying parameters, which included electrolyte concentrations of 1.0 g/L, 2.0 g/L, and 4.0 g/L Na2SO4, pHs of 2, 4, and 6, and constant currents of either 0.100 A or 0.200 A. During the reaction samples were taken before the current was applied and 30 minutes and 60 minute intervals to observe the degradation of …


Modelling Terrestrial And Potential Extraterrestrial Photopigments Via Density Functional Theory, Dorothea Illner May 2024

Modelling Terrestrial And Potential Extraterrestrial Photopigments Via Density Functional Theory, Dorothea Illner

Theses and Dissertations

In the search for extraterrestrial life, biosignatures play a crucial role in identifying its putative traces. A commonly known and robust biosignature is the Vegetation Red Edge (VRE), which can be described as a sharp increase of reflectance observed from a planet and stems from the light absorption of photopigments in specific regions in the electromagnetic spectrum. For Earth, this VRE is known to occur around 700 nm, however, if the photopigments absorb light in different regions and have different structures the VRE could experience a wavelenght shift.

In this work, Chlorophyll a and a potential photopigment precursor called Phot0 …