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Interactive Effects Of Sublethal Concentrations Of Fracking Biocides And Abandoned Mine Drainage On Amphipod Behavior, Kelly Lenhart Dec 2023

Interactive Effects Of Sublethal Concentrations Of Fracking Biocides And Abandoned Mine Drainage On Amphipod Behavior, Kelly Lenhart

Electronic Theses and Dissertations

This thesis examined the sublethal effects of three pollutants, namely glutaraldehyde, 4,4-dimethyloxazolidine (DMO), and abandoned mine drainage (AMD), on amphipods. The primary objective was to investigate their combined effects on amphipods. The three pollutants, despite having the potential to combine in the environment, have not been studied to determine their potential for detrimental interactive effects which could result in unexpected environmental damage.

The research employed a series of experimental setups involving controlled exposure of amphipods to varying, putatively sublethal, concentrations of the chemicals of interest. Subsequently, effects were assessed via both behavioral and feeding assessments. To facilitate this analysis, novel …


Proposing A Measure Of Ethicality For Humans And Ai, Alejandro Jorge Napolitano Jawerbaum Aug 2023

Proposing A Measure Of Ethicality For Humans And Ai, Alejandro Jorge Napolitano Jawerbaum

Electronic Theses and Dissertations

Smarter people or intelligent machines are able to make more accurate inferences about their environment and other agents more efficiently than less intelligent agents. Formally: ‘Intelligence measures an agent’s ability to achieve goals in a wide range of environments.’ (Legg, 2008)

In this dissertation we extend this definition to include ethical behaviour and we will offer a mathematical formalism and a way to estimate how ethical an action is or will be, both for a human and for a computer, by calculating the expected values of random variables. Formally, we propose the following measure of ethicality, which is computable, or …


Examining The Effectiveness Of Using Point-Of-View Video Modeling On Mathematics Improvement In Students With Learning Disabilities In Saudi Arabia, Tirad Alsaluli Aug 2023

Examining The Effectiveness Of Using Point-Of-View Video Modeling On Mathematics Improvement In Students With Learning Disabilities In Saudi Arabia, Tirad Alsaluli

Electronic Theses and Dissertations

Video Modeling (VM) is one of the most widely used approaches by researchers to improve many skills, such as academic skills in students with Learning Disabilities (LD; Boon et al., 2020). As the incidence rate of individuals with LD in Saudi Arabia increase (Almedlij & Rubinstein-Ávila, 2018), the need for evidence-based math interventions focused on the math development of individuals with LD also increases. Although VM is recognized as an Evidence-based Practice (EBPs), a limited number of studies have implemented VM as an intervention to improve mathematic skills. Implementing VM as a math intervention strategy would explore its effects on …


Indirect Aggression And Victimization: Investigating Instrument Psychometrics, Gender Differences, And Its Relationship To Social Information Processing, Taylor Steeves Aug 2023

Indirect Aggression And Victimization: Investigating Instrument Psychometrics, Gender Differences, And Its Relationship To Social Information Processing, Taylor Steeves

Electronic Theses and Dissertations

The study of indirect bullying behaviors, relational aggression and social aggression, has been of theoretical importance and interest to researchers and psychologists within the last few decades. In this investigation, using a convenience sample of 451 late adolescents attending a private university in the mid-Atlantic U.S., I examined the factor structure of two measures of indirect bullying, the Young Adult Social Behavior Scale – Victim (YASB-V) and the Young Adult Social Behavior Scale – Perpetrator (YASB-P). Using confirmatory factor analysis (CFA), I found that the YASB-V comprised a four-factor model, differing from the model that had been identified in the …


Comparative Life Cycle Assessment Of Small Vertical-Axis Wind Turbines And Natural Gas Facility At An Urban University, Mary Kate Ranii Aug 2023

Comparative Life Cycle Assessment Of Small Vertical-Axis Wind Turbines And Natural Gas Facility At An Urban University, Mary Kate Ranii

Electronic Theses and Dissertations

Fossil fuels generate the majority of the electricity in the United States and generate pollutants that negatively affect public and environmental health. Renewable energy projects serve as an opportunity for low-pollution and low-carbon electricity; small-scale projects, such as vertical axis wind turbines (VAWTs), provide opportunities for generation in urban areas close to consumers. Researchers collected wind speed and directional data from a potential turbine installation site at Duquesne University to better demonstrate the potential benefits in an urban university location. The data was used in a life cycle assessment framework and a social review to better understand the value of …


Do Integrated Circuits Make For An Integrated Supply Chain? A Network Analysis Of Trade Flows, Noah Martens May 2023

Do Integrated Circuits Make For An Integrated Supply Chain? A Network Analysis Of Trade Flows, Noah Martens

Electronic Theses and Dissertations

Integrated circuits (colloquially referred to as chips) are an increasingly critical commodity experiencing continuous and substantial rises in demand. These increases in demand recently resulted in shortages. This paper seeks to understand the market for chips and construct a framework by which a network analysis of trade flows can evaluate concentration in the international market for a particular product category. Leveraging this framework and proposing a new model, I evaluate the level and nature of concentration in the chips sector, as well as two key inputs to the manufacturing process, silicon and chip fabricators. I find moderate-to-high levels of concentration …


Hydrologic Modeling With Remote Sensing For The Estimation Of Groundwater Resources Within The Sand River Catchment, South Africa, Sophia Bakar Dec 2022

Hydrologic Modeling With Remote Sensing For The Estimation Of Groundwater Resources Within The Sand River Catchment, South Africa, Sophia Bakar

Electronic Theses and Dissertations

The Sand River Catchment is an important tributary of the transboundary Limpopo River in South Africa, which spans Botswana, Mozambique, South Africa, and Mozambique. Groundwater is a critical resource in the region, especially in the context of population growth and climate change. Data are needed for proper management of these water resources. In regions where groundwater data are sparse in time, space, or both, the most promising solutions come from satellites and hydrologic models. Regional literature suggests that the Soutpansberg Mountains, located within the Sand Catchment, are high-elevation water towers with uncertain groundwater resources. Improved understanding of groundwater resources in …


Assessments Of Water Chemistry And Fish Community Structure In The Buffalo Creek Watershed, Tributary To The Allegheny River In Armstrong And Butler Counties, Pennsylvania, Kathleen Wilson Dec 2022

Assessments Of Water Chemistry And Fish Community Structure In The Buffalo Creek Watershed, Tributary To The Allegheny River In Armstrong And Butler Counties, Pennsylvania, Kathleen Wilson

Electronic Theses and Dissertations

The Buffalo Creek watershed has experienced water quality impairments for various reasons, including but not limited to, agricultural influence, abandoned mine drainage (AMD), on-site wastewater malfunction, and stormwater. The source and cause of the most prevalent impaired areas remains unknown. The goal of this study was to analyze water chemistry using state water quality standards and mass ratio analysis, then to conduct fish community analysis. We found toxic metal pollution across the watershed, with iron, cadmium, copper, and selenium frequently exceeding criteria. We determined which streams are polluted by resource extraction activities by conducting mass ratio analysis. We found conventional …


Speciated Isotope Dilution Mass Spectrometry In Combination With Thor’S Hammer Metaspike Technology For The Assessment Of Low-Level Biomarkers For Human Health Evaluation, Ashley Ebert Dec 2022

Speciated Isotope Dilution Mass Spectrometry In Combination With Thor’S Hammer Metaspike Technology For The Assessment Of Low-Level Biomarkers For Human Health Evaluation, Ashley Ebert

Electronic Theses and Dissertations

Our research team has been focused on quantifying important biological analytes in human blood samples to delineate the biochemical processes underlying certain states of dysfunction and evaluate treatment efficacy. These efforts have been guided by laboratory measurements with the input of medical experts. Speciated isotope dilution mass spectrometry (SIDMS) explained in detail in EPA Method 6800 has been successfully applied in the quantification of an important biomarker analyte for immune function and detoxification processes: glutathione. Past research has proven the molecule a biomarker for autism spectrum disorder (ASD) in the form of the reduced/oxidized glutathione (GSH/GSSG) ratio, and literature has …


Quantum Computations And Molecular Dynamics Simulations: From The Fundamentals Of Antimicrobial Resistance To Neurological Diseases, Angel Tamez Dec 2022

Quantum Computations And Molecular Dynamics Simulations: From The Fundamentals Of Antimicrobial Resistance To Neurological Diseases, Angel Tamez

Electronic Theses and Dissertations

Biophysical phenomena are modeled using a combination of quantum and classical methods to interpret and supplement three distinct and diverse problems in this dissertation. In the first project, decarboxylation reactions are ubiquitous across chemical and biological disciplines, yet the origin of non-catalytic solvent effects remains elusive. Specific solvent structure and energetics have not been well described for the monoanion of malonate, nor corrected from the gas-phase charge-assisted intramolecular hydrogen bond model known as “pseudochair”. In the aqueous phase, a low-lying energy conformer known as the “orthogonal conformation” is computed to be preferred by a three-water cluster of hydrogen bonding over …


Mathematical Models Yield Insights Into Cnns: Applications In Natural Image Restoration And Population Genetics, Ryan Cecil Aug 2022

Mathematical Models Yield Insights Into Cnns: Applications In Natural Image Restoration And Population Genetics, Ryan Cecil

Electronic Theses and Dissertations

Due to a rise in computational power, machine learning (ML) methods have become the state-of-the-art in a variety of fields. Known to be black-box approaches, however, these methods are oftentimes not well understood. In this work, we utilize our understanding of model-based approaches to derive insights into Convolutional Neural Networks (CNNs). In the field of Natural Image Restoration, we focus on the image denoising problem. Recent work have demonstrated the potential of mathematically motivated CNN architectures that learn both `geometric' and nonlinear higher order features and corresponding regularizers. We extend this work by showing that not only can geometric features …


Synthesis And Physicochemical Characterization Of Noncentrosymmetric Quaternary Sulfides With Potential Nonlinear Optical Applications, Andrew J. Craig Aug 2022

Synthesis And Physicochemical Characterization Of Noncentrosymmetric Quaternary Sulfides With Potential Nonlinear Optical Applications, Andrew J. Craig

Electronic Theses and Dissertations

In this work, several new quaternary sulfides were synthesized and investigated for their potential applications in optics. Chapter 1 provides an overview of nonlinear optical (NLO) materials in general, including their applications, ideal characteristics, current deficiencies, and strategies for the discovery of new candidate NLO materials, particularly those for use in the infrared (IR). Two families of compounds are investigated in this work, including Ln3LiTS7 (3-1-1-7) compounds and I4-II-IV2-VI7 (4-1-2-7) diamond-like semiconductors (DLSs). All products were synthesized via traditional high-temperature, solid-state synthesis and their structures were solved and refined through single crystal …


Theory Of Aqueous Solvation: Uninterrupted, Cyclic Hydrogen-Bonding Essential For Accurate Keto-Enol Energies And Grotthuss Tautomerism Of Acetone, Mark Recznik Aug 2022

Theory Of Aqueous Solvation: Uninterrupted, Cyclic Hydrogen-Bonding Essential For Accurate Keto-Enol Energies And Grotthuss Tautomerism Of Acetone, Mark Recznik

Electronic Theses and Dissertations

Keto-enol tautomerization (KET) is a fundamental process impacting a range of molecular phenomena in organic and biochemistry. However, the accurate computation of solution-phase KET energies remains a challenge, even for prototypical acetone.

In Part I, keto-enol tautomers of acetone were incorporated into solvent clusters that interact via uninterrupted, cyclic hydrogen-bonding (UCHB) networks. An empirical model was created to predict accurate KET energies, Etaut, of simple carbonyl compounds. Based on the availability of experimental data and structural simplicity, acetone was selected as a prototype. A discrete-continuum strategy was employed – accounting simultaneously for local noncovalent interactions and bulk-phase effects …


Assessing The Risk Of Land Subsidence In The Lower Limpopo River Basin, Mozambique With Remote Sensing, Gabriella Zuccolotto Aug 2022

Assessing The Risk Of Land Subsidence In The Lower Limpopo River Basin, Mozambique With Remote Sensing, Gabriella Zuccolotto

Electronic Theses and Dissertations

Land subsidence is a threat to coastal cities around the world. In the lower Limpopo River Basin, the presence of compaction-prone alluvial sediments, groundwater use, and reports of saltwater intrusion suggest that subsidence could be occurring. Using interferometric synthetic aperture radar (InSAR) from Sentinel-1, combined with in-situ sea level and river height measurements, this study aims to determine if land subsidence could contribute to increased saltwater intrusion. InSAR results indicate that subsidence in the lower Limpopo River valley has occurred at an average rate of -2.98 cm/yr based on data from the dry seasons (May to October) of 2017-2021. River …


Steps Toward The Total Synthesis Of The Chrysosporazine Family, Katie Kaczynski May 2022

Steps Toward The Total Synthesis Of The Chrysosporazine Family, Katie Kaczynski

Electronic Theses and Dissertations

Cancer is one of the leading causes of death worldwide, with 19.3 million new cancer cases and 10 million deaths in 2020 alone. In the United States, cancer was the second leading cause of death after heart disease. One of the reasons that cancer is so frequently terminal is that cancerous cells frequently develop multidrug resistance (MDR) to frontline chemotherapeutical treatments, resulting in cancers cannot be treated and are inevitably fatal. This makes the discovery of ways to combat MDR so important in the treatment of cancer. The chrysosporazines are a family of recently discovered (2019) natural products that have …


Rooted In The Earth: An Igbo Sacramental Nature Of The Universe, A Model For Igbo Christian Ecological Ethics, Kenneth Oguzie May 2022

Rooted In The Earth: An Igbo Sacramental Nature Of The Universe, A Model For Igbo Christian Ecological Ethics, Kenneth Oguzie

Electronic Theses and Dissertations

The contemporary Igbo society faces a lot of challenges. These include political, religious, and moral crises. These crises affect the environment in many ways. They threaten the peace and harmony of the Igbo society. As a result, it touches on faith. The Igbo society holds a holistic view of life. Whatever affects one aspect of life affects the other areas. Ecologically, various factors are responsible for the crises. These include changes in lifestyle from the traditional way of living to modern style of life with its penchant on consumerism. Also, colonialism and its lingering residues, civil unrests, politics, population growth, …


The Contribution Of Ethical Governance Of Artificial Intelligence & Machine Learning In Healthcare, Tina Nguyen May 2022

The Contribution Of Ethical Governance Of Artificial Intelligence & Machine Learning In Healthcare, Tina Nguyen

Electronic Theses and Dissertations

With the Internet Age and technology progressively advancing every year, the usage of Artificial Intelligence (AI) along with Machine Learning (ML) algorithms has only increased since its introduction to society. Specifically, in the healthcare field, AI/ML has proven to its end-users how beneficial its assistance has been. However, despite its effectiveness and efficiencies, AI/ML has also been under scrutiny due to its unethical outcomes. As a result of this, two polarizing views are typically debated when discussing AI/ML. One side believes that AI/ML usage should continue regardless of its unsureness, while the other side argues that this technology is too …


Biomaterials: From Scaffold Design To Implant Optimization, Jennifer Marie Armen May 2022

Biomaterials: From Scaffold Design To Implant Optimization, Jennifer Marie Armen

Electronic Theses and Dissertations

This work encompasses three individual projects concerning biomaterials and their modifications. Chemically-Induced Cross-Linking of Peptidic Fibrils for Scaffolding Polymeric Particles and Macrophages EAK16-II (EAK) is a self-assembling peptide (SAP) that forms β-sheets and βfibrils through ionic-complementary interactions at physiological ionic strengths. The soft materials can be injected in vivo, creating depots of drugs and cells for rendering pharmacological and biological actions. The scope of the applications of EAK is sought to extend to tissues through which the flow of extracellular fluid tends to be limited. In such anatomical locales the rate and extent of the fibrilization are limited insofar as …


Turbulent Transport Of Dissolved Oxygen In Natural Channels, Alanna Bachtlin May 2022

Turbulent Transport Of Dissolved Oxygen In Natural Channels, Alanna Bachtlin

Electronic Theses and Dissertations

The transport and mixing of dissolved oxygen (DO) is important to replenish the oxygen depleted by natural processes; gas transfer in general has implications for ecosystem metabolism and greenhouse gas transfer. Currently, reaeration coefficients can be found through gas tracer methods, which estimates one-way gas transfer. For this project, a net oxygen consumption rate, , was developed using the similarity equations, which provides a value from DO and velocity profiles specific to a stream site. Additionally, three models to calculate friction velocity, which is required for oxygen consumption rate, were compared. Reynolds stresses, mathematically developed in the Reynolds-Averaged Navier-Stokes Equations, …


The Immobilization Of Ticagrelor On Implant Materials And Corrosion And Biofouling Inhibition By Novel Layered Polymer Thin Films For Marine Application, Tell Lovelace Dec 2021

The Immobilization Of Ticagrelor On Implant Materials And Corrosion And Biofouling Inhibition By Novel Layered Polymer Thin Films For Marine Application, Tell Lovelace

Electronic Theses and Dissertations

Percutaneous coronary interventions are a widely used cardiovascular surgery which is typically accompanied by the insertion of a vascular stent. After the procedure patients are put on dual anti-platelet therapy (DAPT) to prevent stent thrombosis, a common complication to this procedure in which platelets aggregate in the blood vessel on the inserted stent. Systemic deactivation of platelets in patients via oral DAPT results in patients becoming bleeding risks in future medical procedures, necessitating the development of a localized delivery system for anti-platelet medications from the surface of the stent. A novel anti-thrombogenic vascular stent coating has been prepared by covalent …


The Development And Optimization Of A Two-Dimensional Lc-Qqq-Ms-Method For The Combined Analysis Of Synthetic Cannabinoids And Designer Cathinones In Urine, Holly Penefsky Aug 2021

The Development And Optimization Of A Two-Dimensional Lc-Qqq-Ms-Method For The Combined Analysis Of Synthetic Cannabinoids And Designer Cathinones In Urine, Holly Penefsky

Electronic Theses and Dissertations

The compounds and chemical compositions of synthetic cannabinoids and designer cathinones are designed to mimic the intoxicating effects of D9-tetrahydrocannabinol and amphetamines, respectively. In order to skirt existing drug laws, non-controlled ingredients are used, and the original chemical structures of current drugs are being modified using analogs or derivatives. These continually changing chemical compositions pose a problem for policymakers, and forensic and analytical scientists, as users are able to attain a “legal high” and avoid detection in standard drug screens. Commonly, toxicology laboratories utilize a screening method, such as immunoassay, for the presumptive identification of designer drugs. When …


Investigation Of Ongoing Unconventional Gas Extraction And Underground Gas Storage In Pennsylvania: Regulations And Water Quality, Cassandra Ziegler Aug 2021

Investigation Of Ongoing Unconventional Gas Extraction And Underground Gas Storage In Pennsylvania: Regulations And Water Quality, Cassandra Ziegler

Electronic Theses and Dissertations

The extraction of unconventional shale gas and its underground gas storage have the potential to impact surface and groundwater water quality. In New Sewickley Township, Beaver County, Pennsylvania, 54 unconventional gas wells were drilled between 2013 and 2019. Groundwater samples from 33 water wells and surface water from Brush Creek (18 samples) were collected and analyzed for anions, cations, and light hydrocarbons. Results showed that at least 8 wells had indicators of brine contamination, and the surface waters of mine drainage. The Steckman Ridge natural gas storage field in Clearville, Bedford County, PA has 13 active storage wells. Samples were …


Impacts Of Oil And Gas Wastes On Landfill Leachate, Sewage Treatment Plants, And The Environment, Lauren Badertscher Aug 2021

Impacts Of Oil And Gas Wastes On Landfill Leachate, Sewage Treatment Plants, And The Environment, Lauren Badertscher

Electronic Theses and Dissertations

Between January 2011 and March 2021 oil and gas wells in Pennsylvania produced

305,637,795 barrels of liquid waste and 6,992,957 tons of solid waste with the majority from

Marcellus Shale unconventional wells. This waste is not considered hazardous and over 89% of

the solid waste generated by unconventional and conventional oil and gas extraction has been

disposed of in landfills over the past decade. This study examined trends in the quantity of waste

produced and methods of disposal. Landfills accepting this waste were identified and their

general method of leachate treatment, using onsite facilities or offsite at wastewater treatment

plants, …


Quantification Of Persistent Organic Pollutants In Various Matrices Using Stir Bar Sorptive Extraction And Isotope Dilution Mass Spectrometry, Weier Hao May 2021

Quantification Of Persistent Organic Pollutants In Various Matrices Using Stir Bar Sorptive Extraction And Isotope Dilution Mass Spectrometry, Weier Hao

Electronic Theses and Dissertations

A method was developed to quantify persistent organic pollutants (POPs) in a wide range of matrices including wastewater, dietary supplements, and human whole blood using stir-bar sorptive extraction, GC-MS/MS, and isotope dilution mass spectrometry (IDMS). The method enabled accurate, precise, sensitive, and efficient quantification of POPs in these matrices. Compared with calibration curves, IDMS provided measurements with a higher level of accuracy and precision, especially at lower measured concentrations. The use of GC-MS/MS enabled a lower limit of quantification compared with GC-MS. A reverse-IDMS method was performed to further eliminate biases from the labelled concentrations of the commercially available standards. …


Computational And Experimental Studies Of Functionalized Phenolic Tertiary Phosphine Oxides As Organocatalysts For The Redox-Neutral Mitsunobu Reaction, Sadie Brown May 2021

Computational And Experimental Studies Of Functionalized Phenolic Tertiary Phosphine Oxides As Organocatalysts For The Redox-Neutral Mitsunobu Reaction, Sadie Brown

Electronic Theses and Dissertations

The purpose of this thesis was the identification of a more efficient catalyst analog that could perform the redox-neutral Mitsunobu reaction, which was achieved via two synthetic pathways: elimination-addition and addition-rearrangement. Furthermore, a computational investigation was conducted on the conflicting interpretations of the catalytic cycle. Our research group replicated Houk et al. work, as well as expanded the computations to examine the influence different functional groups had on the ground state and transition state structures. Important ground state and transition state structures were determined, which provided a more energetically favorable pathway of the catalytic cycle. Experimental work demonstrated that both …


Air Pollution In The Steel City: Assessing The Influence Of Covid-19 On Air Pollution In Allegheny County, Carissa L. Lange May 2021

Air Pollution In The Steel City: Assessing The Influence Of Covid-19 On Air Pollution In Allegheny County, Carissa L. Lange

Electronic Theses and Dissertations

Though the novel coronavirus (COVID-19) has sickened millions of individuals, lockdown measures have provided a unique opportunity to analyze air pollution reductions. Reductions in air pollution are especially important in a city like Pittsburgh, where industrial activity has led to elevated levels of particulate matter with an aerodynamic diameter 2.5). The majority of this PM2.5 pollution comes from two industrial facilities, the Edgar Thomson Steel Works and the Clairton Coke Works. By utilizing a natural experiment, this study sought to determine how large of a role the COVID-19 lockdowns played in improving air quality in the Pittsburgh region. Data …


Accurate Quantitation Of Hexavalent Chromium For Reference Standard Certification And Quality Control Testing Using Speciated Isotope Dilution Mass Spectrometry, James E. Henderson Dec 2020

Accurate Quantitation Of Hexavalent Chromium For Reference Standard Certification And Quality Control Testing Using Speciated Isotope Dilution Mass Spectrometry, James E. Henderson

Electronic Theses and Dissertations

The ability to perform accurate, repeatable, and defensible elemental and molecular speciated analysis is immensely significant for measurements that support human health, environmental science, and industry. This is especially true since trivalent chromium [Cr(III)] is necessary for proper nutrition, while hexavalent chromium [Cr(VI)] is extremely toxic, genotoxic, and carcinogenic. The main challenges associated with speciated analysis are related to reactive species that are continuously transformed or converted to other species during sample processing. Accurate determination of Cr(III) and Cr(VI) species require a method that is capable of monitoring and correcting for interconversion, bias, and instrumental error. Traditional quantitative methods, such …


Atom Transfer Radical Processes: From Catalyst Design To Polymer Synthesis, Characterization, And Application, Michael Novak Dec 2020

Atom Transfer Radical Processes: From Catalyst Design To Polymer Synthesis, Characterization, And Application, Michael Novak

Electronic Theses and Dissertations

Due to the toxicity of heavy metals and their prevalence in the environment there exists a need to develop highly active transition metal catalysts ultimately reducing the amount needed for chemical transformations. Additionally, there is interest in the scientific community for creating new materials that can remove these pollutants from industrial wastewater prior to its release into the environment. The work presented here focuses on the reduction and removal of heavy metals from industrial hazardous waste by designing novel highly active catalysts and developing polymeric adsorbents.

Highly active catalyst complexes consisting of novel hybrid ligands, 2-(dimethylamino)ethyl-bis-[2-(pyridylmethyl)amine] (M1-T2), and bis[2-(dimethylamino)ethyl]-2-(pyridylmethyl)amine (M2-T1), …


Fluoride Removal With Augmented Bentonite In Drinking Water And Community Perceptions In Arusha, Tanzania, Kara Okular Dec 2020

Fluoride Removal With Augmented Bentonite In Drinking Water And Community Perceptions In Arusha, Tanzania, Kara Okular

Electronic Theses and Dissertations

High fluoride concentrations in drinking water affect millions of people around the world. The World Health Organization recommended a fluoride concentration in drinking water of ≤ 1.5 mg/L; fluoride above this concentration can cause long-term dental and skeletal fluorosis. Fluoride imparts no taste to water; therefore, people do not realize that they are ingesting high fluoridated water. Researchers sought to develop a material to remove fluoride from drinking water through sorption. Aluminum was used to form a double ionic layer on the bentonite clay surface. Once mixed in contaminated water, a coagulant, ferric sulfate, was used to separate the bentonite …


Functionalized Materials From Atom Transfer Radical Processes, Sean Fischer Dec 2020

Functionalized Materials From Atom Transfer Radical Processes, Sean Fischer

Electronic Theses and Dissertations

This work is focused on the synthesis, characterization, and application of functionalized materials prepared from atom transfer radical processes. Atom transfer radical processes encompass both atom transfer radical addition (ATRA) and polymerization (ATRP) reactions, both of which are catalyzed by ppm amounts of copper complexes. The synthetic efforts of ATRA include increasing adduct selectivity through optimization of reaction conditions to generate small molecules in high to moderate yields. ATRA provides retention of the halogen moiety, which is an attractive functional group that can be further modified with other transformations. Specifically, the copper-catalyzed azide-alkyne [3+2] cycloaddition (CuAAC) allows for the realization …