Physical Sciences and Mathematics Commons^™

Application Of Functionalized Organosilicas In Adsorption Of Nitrates, Stephen Amoako

Electronic Theses and Dissertations

This study addresses the critical environmental issue of elevated nitrate levels in water bodies, primarily due to excessive use of nitrogenous fertilizers and improper waste disposal. It focuses on reducing nitrate concentrations in polluted water to permissible levels through the effectiveness of hybrid materials in nitrate adsorption. We synthesized nine amino-functionalized adsorbents using grafting and sol-gel techniques. Batch adsorption tests confirmed the high nitrate adsorption capacities of these adsorbents, with sol-gel materials showing the highest efficiency due to their abundant amino group contents. Among these, the surfactant-free, sol-gel adsorbent was the most effective, combining ease of synthesis with cost-efficiency. Our …

Assessing The Reactivity Of Amino Acids To Chlorination Using Capillary Electrophoresis, Pedro De Allende

Electronic Theses, Projects, and Dissertations

Amino acids (AA) are ubiquitous in wastewater systems. One of the most popular wastewater treatments is chlorination which is effective at eradicating bacteria and overall treating the wastewater, but it can also produce disinfection by-products (DBPs). Certain DBPs have been classified as Class B Carcinogens to humans and are therefore highly regulated and monitored. Past studies have shown that natural organic matter (NOM), specifically amino acids, can be precursors to DBPs if chlorinated to the correct dose. This thesis project explored AA chlorination's mechanism(s) to understand further which products arise. In particular, the investigation detailed which steps of the mechanism …

Excited State Processes In Radical Elaborated Platinum Donor-Acceptor Complexes, Sangita Paudel

Chemistry and Chemical Biology ETDs

Organo-transition metal complexes are being widely studied to understand their photophysical properties for their wide range of applications as efficient emitters in organic light emitting diodes (OLEDs), light emitting electrochemical cells (LEECs), etc. Cyclometalated organo-transition metal complexes such as cyclometalated square planar platinum(II) complexes are becoming suitable candidates for such applications because of their highly efficient luminescence. Understanding the excited properties of such complexes is useful in designing highly efficient and color tunable phosphors with desired excited state lifetimes. We aim to explore the influence of radical substituents on electronic structure, luminescence quantum efficiencies, and excited state lifetimes by synthesizing …

Potent And Selective Small Molecule Mcl-1 Inhibitor Demonstrates Anti-Myeloma Activity And Overcomes Chemotherapy Resistance, Omar Sami Faleh Al-Odat

Theses and Dissertations

Despite a record number of clinical studies investigating various anti-myeloma treatments, the 5-year survival rate for multiple myeloma (MM) patients in the US is only 55%, and nearly all patients relapse. Poor patient outcomes demonstrate that myeloma cells are "born to survive” which means they can adapt and evolve following treatment. Thus, new therapeutic approaches to combat survival mechanisms and target treatment resistance are required. Importantly, Mcl-1, anti-apoptotic protein, is required for the development of MM and treatment resistance. This study looks at the possibility of KS18, a selective Mcl-1 inhibitor, to treat MM and overcome resistance. Our investigation demonstrates …

Implementing 1.5 Millimeter Internal Diameter Columns And A Portable Capillary Column Instrument Into Monoclonal Antibody Analytical Workflows, Benjamin Libert

Theses and Dissertations

Using 1.5 mm inner diameter (i.d.) columns to bridge the gap between routinely used 2.1 mm i.d. columns and capillary bore columns allows for a sequential but significant increase in performance without the need for specialized equipment associated with very low dispersion liquid chromatography (LC) systems. These 1.5 mm i.d. columns balance an increase in sensitivity compared to 2.1 mm i.d. columns (theoretically doubling the time-domain peak area in mass sensitive detectors for the same mass load), while mitigating the efficiency losses due to extra-column dispersion effects that are commonly observed with 1.0 mm i.d. columns. Here, the use of …

Student Perceptions: How Stem Students Value Belonging Interventions, Elizabeth Runkel Baez

University Honors Theses

With the prioritization of increasing Science, Technology, Engineering, and Mathematics (STEM) graduates in the United States, researchers have become increasingly interested in how to promote STEM students' sense of belonging. Sense of belonging is considered a marker of persistence in STEM. Facilitated 'belonging interventions' are one way to strengthen a sense of belonging amongst STEM students. How students respond to, value, and understand these belonging interventions is relatively understudied. In this study, focus groups were conducted with STEM students from a single university to investigate how they value an in-class belonging activity. Qualitative thematic coding of focus group responses revealed …

Evaluating The Efficiency Of Low-Cost Air Quality Sensors At A Suburban Field Site, Olivia Wuttke

Undergraduate Theses, Capstones, and Recitals

Science surrounding the use of low-cost sensors (LCS) to monitor air quality is rapidly expanding to satisfy the need to fill in regional air quality data gaps. This project evaluated the suitability of two types of LCS: Modulair-PM and PurpleAir (SD and Flex models) as efficient means to measure airborne particulate matter. The study involved physical installation of nine co-located sensors at a suburban site in Denver, connectivity troubleshooting as necessary, and data analysis/modeling of data over multiple months (19 weeks). PM data was compared between individual sensors of the same type, as well as across the two different sensor …

Positron Emission Tomography In Oncology And Environmental Science, Samantha Delaney

Dissertations, Theses, and Capstone Projects

The last half century has played witness to the onset of molecular imaging for the clinical assessment of physiological targets. While several medical imaging modalities allow for the visualization of the functional and anatomical properties of humans and living systems, few offer accurate quantitation and the ability to detect biochemical processes with low-administered drug mass doses. This limits how physicians and scientists may diagnose and treat medical issues, such as cancer, disease, and foreign agents.

A promising alternative to extant invasive procedures and suboptimal imaging modalities to assess the nature of a biological environment is the use of positron emission …

Moss Biomonitoring Of Lead Emissions From Hillsboro Airport, Daria Kolpakov

University Honors Theses

The objective of this experiment was to use biomonitoring as a method to determine lead concentration levels around Hillsboro Airport in Hillsboro, Oregon. Twenty-two samples were collected within a 2 km radius around Hillsboro Airport using a randomized sampling strategy. The concentrations of lead within the samples were determined using ICP-MS. The average lead concentration was (2.8 ± 5.0) mg/kg with a peak value of 21.6 mg/kg 0.57 km from Hillsboro Airport. As the average lead concentration was substantially skewed, Hillsboro Airport is likely to be the source of the lead increase.

Predicting Rheology Of Uv-Curable Nanoparticle Ink Components And Compositions For Inkjet Additive Manufacturing, Cameron D. Lutz

Master's Theses

Inkjet additive manufacturing is the next step toward ubiquitous manufacturing by enabling multi-material printing that can exhibit various mechanical, electronic, and thermal properties. These characteristics are realized in the careful formulation of the inks and their functional materials, but there are many constraints that need to be satisfied to allow optimal jetting performance and build quality when used in an inkjet 3-D printer. Previous research has addressed the desirable rheology characteristics to enable stable drop formation and how the metallic nanoparticles affect the viscosity of inks. The contending goals of increasing nanoparticle-loading to improve material deposition rates while trying to …

Molecular-Level Studies Of Nanopatterned Biomolecules With Atomic Force Microscopy, Ashley R. Walker

LSU Doctoral Dissertations

Atomic force microscopy (AFM) is an analytical technique in which a tipped probe is gently scanned across the surface in a raster pattern to generate digital images of a sample at the nanoscale. The AFM instrument has three general operational modes, which are contact, non-contact and tapping-mode, that can be used to examine materials at the atomic level. Single-molecular details of biological molecules and other soft organic materials can be captured with minimal denaturation in either ambient or liquid environments when using tapping-mode AFM. In tapping-mode, the probe is driven to oscillate vertically while the tip is scanned across the …

Comparing Proliferation Rates And Collagen Production Of Cells Treated With Cuhars, Katie Elizabeth Mckenzie

Master's Theses

Cartilage is the padding in joints that protects the bones and aids in motion. Problems with the cartilage in the knee can be caused by mechanical damage or diseases like osteoarthritis. Chondrocytes make cartilage. The objective of this study is to determine the doubling time of chondrocytes per passage. I also want to determine the base amount of collagen-II created by chondrocytes as they age. I also want to determine how long it takes CuHARS to break down in different cell medias. Chondrocytes, human dermal fibroblasts, and CRL 2303 cells were grown and cultured for over a year. During that …

The Lewis Acidity Of Imidazole-Derived Diaryliodonium Zwitterions, Cyrus Rose

University Honors Theses

Diaryliodonium salts can be used as effective aryl-transfer agents in reactions to form novel molecules with diverse applications including pharmaceuticals and agrochemicals without using harsh reaction conditions and transition metal reagents. In recent years, interest in the applications of the Lewis acidity of iodonium ion catalysts has increased. Despite this, the quantification of the Lewis acidities of diaryliodonium salts are scarce. Even rarer, there has not been much study into the Lewis acidities of zwitterionic diaryliodonium salts. For zwitterions, there is no counter anion that would come into consideration in regard to its Lewis acidity. To expand the understanding of …

Releases Of Hazardous Materials And Waste From Transportation Incidents In The Us: An Analysis To Increase Environmental Resiliency, Elizabeth Irene Tautges

Master's Projects and Capstones

Excessive amounts of hazardous materials and waste are released into the environment from transportation incidents. The United States federal government has regulations on the movement of hazardous material and waste during transportation, but preventing environmental releases is not a major priority. Multiple external factors influence the release of hazardous material and waste into the environment. Transportation incidents can be prevented by modifying the information collected in emergency reports, adjusting transportation patterns and conditions, and expressing negative environmental impacts, preparing responder efforts to communicate effectively. The components of previous hazardous materials and waste releases emphasize the needed improvements for increasing environmental …

Non-Destructive Determination Of Surface Area In Reverse Phase Chromatographic Columns, Margaret Figus

Seton Hall University Dissertations and Theses (ETDs)

Excess adsorption isotherms of acetonitrile and methanol from water were measured on eight commercial columns. Columns used in this study represent the latest examples in column development and include three different poroshell columns (Kinotex C18, Ascentis C18, and Halo C18) as well as conventional columns with significantly different adsorbent geometries (Allure C18, YMC C18) and various hybrid-silica columns (Gemini C18, Xterra C18, and XBridge C18). Comparison of the excess adsorption isotherms measured on all these columns and expressed in surface-specific form demonstrated significant similarity of the adsorption properties of all columns, which allows the introduction of the Standard Excess Adsorption …

Advancing Coupled Cluster Methods: Tensor Factorization And Analytic Gradient Implementation, Tingting Zhao

Chemistry Theses and Dissertations

With the rapid advancement of computing capabilities, computational chemistry has become increasingly indispensable in both experiment design and the interpretation of experimental outcomes. Wave-function-based quantum mechanistic methods are highly sought after for their ability to provide high-accuracy data and their potential for systematic improvement. However, to extend their applicability to larger molecules, it is essential to employ rank-reducing approximations to these methods. This dissertation dedicates Chapters Three and Four to the development of rank-reduced methodologies. Additionally, beyond single-point energies, molecular geometries and properties of molecule-excited states hold paramount importance across diverse fields of chemistry. Hence, Chapter Five presents the work …

Towards Carbon Dioxide Reduction: Synthesis And Characterization Of Ccc-Nhc Pincer Iron Complexes., Joshua Mensah

Theses and Dissertations

The industrial revolution came with its downside of emission of greenhouse gases into the atmosphere. The NOAA reported in 2019 that, of the greenhouse gases emitted into the atmosphere, CO2 contributed to about 80% of the increased greenhouse gases hence the need for CO2 Sequestering and Storage (CSS) and ultimately leading to Carbon Capture and Recycling (CCR) as a viable option to convert CO2 into useful forms. The race to find the best catalyst for CCR has led to the synthesis of many organometallic compounds. Pincer complexes catalyzed CO2 reduction has gained notoriety recently because of the tunability and robustness …

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 …

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, …

Modeling Sex-Specific Changes In Myocardial Fibrosis, Grace Martin

Chemical Engineering Undergraduate Honors Theses

Heart disease the leading cause of death for both men and women in the United States. Cardiac fibrosis, or accumulation of extracellular matrix proteins in the heart, can occur after a heart attack and increase the risk for further complications. Current treatments for heart disease do not include extracellular matrix regulators, partly due to the complicated signaling network responsible for the production of these proteins. By using a computational model of the signaling network in cardia fibroblasts, the relationship between particular molecules and downstream extracellular matrix production can be examined.

Biological sex is an important factor for cardiac health and …

A Chemical And Historical Analysis Of Beer: Discovering Brewing Styles And Beer Stages, Alexander Taylor '24

Honor Scholar Theses

This interdisciplinary project is designed to explore both the compositional qualities of beer during the brewing process and its impact on society from a cultural, economic, and social viewpoint. Comparing various styles of beer against each other in a historical, societal, and chemical lens allows for a deeper understanding of what creates a beer’s identity, and what makes it different from other styles. Here we analyzed two different styles of beer, a bock lager and a saison ale, in order to determine their chemical composition through their developmental stages to their final product. Based on previously published research and extended …

Mathematical Modeling And Examination Into Existing And Emerging Parkinson’S Disease Treatments: Levodopa And Ketamine, Gabrielle Riddlemoser

Undergraduate Honors Theses

Parkinson’s disease (PD) is the second most common neurodegenerative disease across the world, affecting over 6 million people worldwide. This disorder is characterized by the progressive loss of dopaminergic neurons within the substantia nigra pars compacta (SNpc) due to the aggregation of α-synuclein within the brain. Patients with PD develop motor symptoms such as tremors, bradykinesia, and postural instability, as well as a host of non-motor symptoms such as behavioral changes, sleep difficulties, and fatigue. The reduction of dopamine within the brain is the primary cause of these symptoms. The main form of treatment for PD is levodopa, a precursor …

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, …

Use Of Molecular Logic Gates For The Tuning Of Chemosensor Dynamic Range, Orhan Acikgoz

Undergraduate Honors Theses

The first molecular logic gates were created in the 1990s; integrating such logic gates into fluorescent chemosensors allowed for the detection of different types of ions in solution. In this study, we have developed a new use of molecular logic gates by having two of the same type of binding site. The two binding sites on a fluorophore that both detect Na⁺ ions led to an increase in the detection limit compared with the chemosensor with a single binding site. Since the two sodium binding sites create an AND logic gate, two sodium ions are needed to generate a …

Modeling Group 3 Medulloblastoma: Describing The Interconnected Pathway Of The Most Common Pediatric Brain Cancer, Amber Cantú

Undergraduate Honors Theses

Group 3 medulloblastoma is one of the most common pediatric brain cancers. Affecting infants and children, this cancer has the worst prognosis of the medulloblastoma group. Current treatments use surgical resection, radiation, and chemotherapy to afflict the cancer, however no cure has been found. This project aims to model one of the many pathways being investigated in Group 3 medulloblastoma which may be used to synthesize future treatments. Specifically, showing the interconnections between various precursors of BCL-xL, an antiapoptotic protein, and how these factors influence the progression of the disease. Scientific databases were used to find previous research articles which …

Development Of Chiral Lewis Base Catalysts For Chlorosilane-Mediated Asymmetric C-C Bond Formations, Changgong Xu

Theses and Dissertations

The chiral hydrazine is a crucial structural motif that serves as pivotal structural elements in numerous natural products and biologically significant molecules. We are particularly interested in the catalytic asymmetric reduction of hydrazones, as well as the catalytic asymmetric propargylation and allenylation of hydrazones, because they provide direct pathways to these enantio-enriched chiral building blocks. In this work, we will explore the potential of two different categories of chiral Lewis base catalysts in the said transformations.

Developed by another student in our group, axial-chiral 3,3’-triazolyl biisoquinoline N,N’-dioxides derived catalysts are tested and demonstrated its capability in activating various hydrazone …

Argonaute 2 Binding Affinity To Determine Repression Of Mirna-Mrna Pairs, Christina M. S. Karadiakos

ALL - Honors Theses

MicroRNAs (miRNA) are a class of small non-coding RNAs that play a key role in gene silencing. miRNAs form an RNA-induced silencing complex (RISC) with the argonaute 2 (AGO2) protein in order to control gene expression through silencing messenger RNAs (mRNA). The ability for a miRNA-mRNA complex to fit into AGO2 and form the RISC is based on the location and characteristics of a central bulge, but the mechanism and interactions that lead to a functional RISC remain unknown. Using available experimental data, we modeled complexes composed of a miRNA (miR-34a) and different mRNA sequences inside of AGO2. The resulting …

Harnessing The Power Of Virtual Reality For Organic Chemistry Education, Jungmin Shin

Undergraduate Honors Theses

Understanding organic chemistry concepts heavily relies on visualization of the geometry of molecules and spatial arrangement of molecules during mechanisms. 2D textbook depictions have their limitations in visualizing the three-dimensionality of organic chemistry. Student learning outcomes could be greatly improved from 3D visualizations of these topics. This project explores the potential of an emerging technology, Virtual Reality (VR), being incorporated as a teaching resource for organic chemistry.

This paper discusses two trials for evaluating the potential of VR as a teaching resource for organic chemistry in select topics of the Diels-Alder reaction and R/S configurations and stereoisomers. The Diels-Alder reaction …

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

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 …