The Application Of Biological Processes To Increase Energy Potential In Landfills,
2022
Taylor University
The Application Of Biological Processes To Increase Energy Potential In Landfills, Ashlyn Eisenhart
Chemistry
There has been a dramatic increase in the amount of waste that we humans have created. This has been due to population growth, an increase in industrial manufacturing, along with urbanization and modernization.8 The number of tons of municipal solid waste entering landfills has increased from 82.5 million tons in 1960 to 146.1 million tons in 2018.17 However, thanks to recycling, composting, and energy recovery from combustion, the percentage of solid waste going to landfills has dramatically decreased, from around 93.6 to about 65.4 percent.17
A Comparative Study Of Two Nickel-Based Suzuki-Miyaura Hybrid Molecular Catalysts,
2022
University of South Carolina - Columbia
A Comparative Study Of Two Nickel-Based Suzuki-Miyaura Hybrid Molecular Catalysts, Mollie Morrow
Senior Theses
Two molecular nickel-based catalysts, (2,2’bipyridine-4,4’-carboxylic acid)nickel(II) chloride and (2,2'-bipyridine-4,4'-diamidopropylsilatrane)nickel(II) chloride, were synthesized and subsequently attached to a solid support in the form of amorphous silicon dioxide to create two hybrid molecular/heterogeneous catalysts. Characterization using ICP-MS and ATR-FTIR confirms that both catalysts are bonded to the SiO2 support. The catalysts were both able to catalyze a Suzuki-Miyarua cross-coupling which their molecular counterparts were unable to; the carboxylate catalyst was able to achieve yields of 10% and the silatrane catalyst achieved yields of up to 50%. Post-reaction analysis indicated that while some catalyst desorption occurred in both complexes, active catalytic species …
Synthesis Of Phosphonate-Based Diimide Ligands,
2022
St. Mary's University
Synthesis Of Phosphonate-Based Diimide Ligands, Kenya V. Medina, Adelani Pius
Honors Program Theses and Research Projects
There has been a resurged interest in the synthesis of metal-organic frameworks because of their potential applications in energy production and drug delivery. Although diimides are insoluble in aqueous solutions, the addition of phosphonic acid allows the complex to be water soluble, which greatly increases their application. Therefore, the creation of a hybrid metal-organic complex by the addition of phosphonic groups to diimide ligands can result in a polar porous compound. In this project the ligand design included the use of dianhydrides including pyromellitic dianhydride, naphthalenetetracarboxylic dianhydride, perylenetetracarboxylic dianhydride, and biphenyl-tetracarboxylic acid dianhydride. These dianhydride precursors were refluxed under argon …
Solid State Nmr Spectroscopic Characterization Of Metal Organic Frameworks,
2022
The University of Western Ontario
Solid State Nmr Spectroscopic Characterization Of Metal Organic Frameworks, Vinicius Martins
Electronic Thesis and Dissertation Repository
Metal-organic frameworks are porous organic-inorganic materials that have attracted enormous attention due to their promising capabilities for several technologies, including carbon dioxide capture and storage, gas separation, and heterogeneous catalysis. The performance of MOFs for these applications is directly linked to their properties and, by extension, structures. Therefore, it is essential to understand the structure – property relationship. Solid-state NMR (SSNMR) spectroscopy is a technique that provides complementary information to X-ray diffraction-based techniques. SSNMR can provide short-range information around the NMR-active nucleus of interest. Furthermore, SSNMR can provide additional information regarding host-guest interactions and dynamics of adsorbed molecules, which play …
Transition Metal Phosphides For High Performance Electrochemical Energy Storage Devices,
2022
American University in Cairo
Transition Metal Phosphides For High Performance Electrochemical Energy Storage Devices, Amina Saleh
Theses and Dissertations
Electrochemical energy storage technologies are nowadays playing a leading role in the global effort to address the energy challenges. A lot of attention has been devoted to designing hybrid devices known as supercapatteries which combine the merits of supercapacitors (high power density) and rechargeable batteries (high energy density). Transition metal phosphides (TMP) are a rising star for supercapattery anode materials thanks to their high conductivity, metalloid characteristics, and kinetic favorability for fast electron transport. Herein, new TMP-based materials were synthesized for use as supercapattery positive electrodes, via a multifaceted approach to yield devices enjoying concurrently high power and energy densities. …
Pascoite Minerals And Potential Application Of Nmr Spectroscopy,
2022
Illinois State University
Pascoite Minerals And Potential Application Of Nmr Spectroscopy, Craig C. Mclauchlan, Beth Trent-Ringer, Debbie C. Crans
Faculty Publications – Chemistry
The 20 minerals encompassing the pascoite family of decavanadate isopolyanion-containing [V10O28]6− minerals include a few minerals, such as rakovanite, that have been described as containing a protonated decavanadate anion. Rakovanite was originally assigned the formula Na3[H3V10O28]•15H2O and now is redefined with an ideal formula (NH4)3Na3[V10O28]•12H2O. Nuclear magnetic resonance (NMR) and particularly 51V NMR spectroscopy is an informative method used to describe the protonation state and speciation in both solid and solution states …
Using Powder Diffraction To Give Insight Into Structures Of Ir2(Diisocyanomenthane)4x2 [Dimen] (X = Cl; Pf6; Bph4),
2022
Claremont Colleges
Using Powder Diffraction To Give Insight Into Structures Of Ir2(Diisocyanomenthane)4x2 [Dimen] (X = Cl; Pf6; Bph4), Mairead Brownell
Scripps Senior Theses
Ir2(dimen)42+ (dimen = 1,8-diisocyanomenthane) has been studied extensively as model compound to better understand catalysis of photochemical reactions. Although Ir2(dimen)42+ has been used primarily to observe the photophysical changes of metal-metal transitions, it gives great insight into the transitions that allow other d8-d8 metal complexes to undergo photochemical processes and generate hydrogen gas. The large visible range by which Ir2(dimen)42+ (1) can be electronically excited in solution is indicative of its two solution phase ground states, which interestingly have been hypothesized to resemble two unique packing structures observed in the powder state. In this study, the powder diffraction patterns of …
Synthesis And Characterization Of Ruthenium Complexes And Their Potential And Photosensitizers For Photodynamic Therapy,
2022
Loyola University Chicago
Synthesis And Characterization Of Ruthenium Complexes And Their Potential And Photosensitizers For Photodynamic Therapy, Keit Dine
Master's Theses
Cancer is one of the leading causes of death in the world with over 10 million people dying of the disease every year. Inorganic complexes supported by platinum metal centers are often used in cancer treatment. However, these complexes lack selectivity for tumor cells. As such, other alternatives to platinum have been explored. Ruthenium (Ru) complexes are one of the most promising candidates due to their ability to be used as photosensitizing drugs in photodynamic therapy. Herein, we report the design, synthesis, and characterization of two novel ruthenium-based complexes. One compound is a Ru(II) homoleptic complex, while the other is …
Synthesis And Reactivity Of Flexible Dicopper Bis(Pyridyldiimine) Macrocyclic Complexes,
2022
University of Pennsylvania
Synthesis And Reactivity Of Flexible Dicopper Bis(Pyridyldiimine) Macrocyclic Complexes, Sam Brooks
Publicly Accessible Penn Dissertations
Methanol is a viable fuel source and a common feedstock in the chemical industry. Currently, much of the methanol produced by industry is derived from natural gas (methane). Yet, the one-step selective oxidation of methane to methanol remains challenging due to the potential formation of overoxidation products (CO2, H2O, etc.). Within the past 20 years, the reactive Cu2(II,II)-µ-O site within Cu(II)-ZSM-5 has been shown capable of the selective oxidation of methane to methanol through a hydrogen atom transfer (HAT)/radical rebound mechanism. The proximity of the metals and geometric constraints may allow for the copper centers to work in concert when …
S-Type Stars: Lao Line List For The B²Σ⁺-X²Σ⁺ Band System,
2022
Old Dominion University
S-Type Stars: Lao Line List For The B²Σ⁺-X²Σ⁺ Band System, P. F. Bernath, Randika Dodangodage, J. Liévin
Chemistry & Biochemistry Faculty Publications
LaO bands are a characteristic feature in the spectrum of cool S-type stars. La is made primarily by the s-process during the asymptotic giant branch phase of stellar evolution. The B2Σ+–X2Σ+ and A2Π–X2Σ+ band systems can be used to determine the La abundances in cool S stars. The bands of the B2Σ+–X2Σ+ with v' and v" ⩽ 5 have been rotationally analyzed from an emission spectrum from a carbon furnace. Line strengths are calculated using an ab initio transition dipole …
The Synthesis And Characterization Of Pb(Ii) Cyanoximates,
2022
Missouri State University
The Synthesis And Characterization Of Pb(Ii) Cyanoximates, Patricia Mcdaniel
MSU Graduate Theses
A new series of Pb(II) cyanoximates were synthesized and characterized by elemental analysis (C, H, N, S), IR spectroscopy, thermal analysis, and X-ray crystallography. The goal was to synthesize compounds with a PbL2 (L= selected known chelating cyanoximes) composition for use as potential new non-linear optical (NLO) materials, specifically second harmonic generators (SHG), which must belong to non-centrosymmetric space groups. A desktop procedure using Pb2+ is chosen due to its typically active 6s2 lone pair of electrons, which are known to distort central polyhedra. A 1:2 ratio of Pb(II) to ligand were used to synthesize bulk products …
Analysis Of The Light Responsive Azobenzene Peptide Nucleic Acid Duplexes,
2022
Georgia Southern University
Analysis Of The Light Responsive Azobenzene Peptide Nucleic Acid Duplexes, Kat Nguyen
Honors College Theses
Peptide nucleic acids (PNAs) are oligonucleotide analogues in which the sugar-phosphate backbone has been replaced by a pseudopeptide skeleton. Since PNAs use the natural nucleobases (Adenine, Thymine, Cytosine, Uracil, and Guanine) found in either DNA and/or RNA, they are able to hybridize according to Watson-Crick base-pairing to form duplexes. PNA is a promising therapeutic agent because they can function as antigene or antisense chemical agents. To further enhance their utility, we aim to incorporate a photoswitchable moiety using azobenzene. Here, we report the results of the synthesis and purification of a photoswitchable 11 mer PNA along with initial characterization efforts.
Modeling, Fabrication, And Characterization Of Rf-Based Passive Wireless Sensors Composed Of Refractory Semiconducting Ceramics For High Temperature Applications,
2022
West Virginia University
Modeling, Fabrication, And Characterization Of Rf-Based Passive Wireless Sensors Composed Of Refractory Semiconducting Ceramics For High Temperature Applications, Kavin Sivaneri Varadharajan Idhaiam
Graduate Theses, Dissertations, and Problem Reports
Real-time health monitoring of high temperature systems (>500oC) in harsh environments is necessary to prevent catastrophic events caused by structural failures, varying pressure, and chemical reactions. Conventional solid-state temperature sensors such as resistance temperature detectors (RTDs) and thermocouples are restricted by their operating environments, sensor dimensions and often require external power sources for their operation. The current work presents the research and development of RF-based passive wireless sensing technology targeting high temperatures and harsh environmental conditions. Passive wireless devices are generally classified as near-field and far-field devices based on the interrogation distance. Near-field sensors are placed at …
Synthesis, Characterization, And Activation Of Pyridine Dipyrrolide Supported Vanadium-Nitrogen Multiple Bonds,
2022
West Virginia University
Synthesis, Characterization, And Activation Of Pyridine Dipyrrolide Supported Vanadium-Nitrogen Multiple Bonds, Jordan Cruz Martinez
Graduate Theses, Dissertations, and Problem Reports
The chemistry of coordination complexes of vanadium supported by pyridine di-pyrrolide pincer ligands was probed via the synthesis and investigation of a variety of compounds from the trivalent starting material, (MesPDPPh)VCl(thf)2. Under reducing conditions and subsequent addition of terpyridine, a redox transfer series (1-, 0, 1+) stemming from the neutral product (MesPDPPh)V(terpy) was isolated and characterized by X-ray crystallography. The precise bond lengths, in conjunction with bulk magnetic susceptibility, allowed for a detailed study of the redox non-innocence of polypyridyl ligands in these systems.
Metathesis of the halide starting material …
Dirhenium Compounds Containing The Diphosphine Ligands Ph2pch2pph2, Ph2pch(Cn)Pph2, Or Ph2pch(Ch3)Pph2: A Comparative Study,
2022
Hollins University
Dirhenium Compounds Containing The Diphosphine Ligands Ph2pch2pph2, Ph2pch(Cn)Pph2, Or Ph2pch(Ch3)Pph2: A Comparative Study, Hannah C. Arthur
Undergraduate Honors Theses
When M2L10 complexes containing two rhenium(III) atoms in a quadruple bond react with an excess of the diphosphine ligand Ph2PCH2PPh2, the bond order decreases, and the rhenium is reduced to rhenium(II). When two diphosphine ligands are bonded to the dirhenium center, they can adopt a trans-trans, trans-cis, or cis-cis configuration. NMR spectra of compounds that adopt the cis-cis arrangement show unusually large downfield shifts for one of the bridgehead methylene hydrogens (P-CH2-P). To understand the unusual chemical shift, the hydrogens first have to be assigned. The strategy for …
The Effects Of Solution Ph, Temperature And Redox Environment On Corrosion And Oxide Formation On Inconel X-750,
2021
The University of Western Ontario
The Effects Of Solution Ph, Temperature And Redox Environment On Corrosion And Oxide Formation On Inconel X-750, Mohsen Bahrami
Electronic Thesis and Dissertation Repository
Nickel-based superalloys have a wide range of applications in different industries due to their exceptional mechanical and corrosion-resistance properties. These alloys are widely employed in the nuclear industry. Inside a nuclear reactor, these alloys are exposed to a continuous flux of gamma-radiation. When exposed to gamma-radiation, water decomposes, resulting in the production of oxidizing and reducing species. These species have a considerable effect on the redox chemistry of the solution, which controls the overall corrosion behaviour of nickel-based superalloys.
Corrosion of metals and alloys involves several elementary steps. A comprehensive understanding of these steps and how they influence each other …
Production And Adsorption Of Volatile Tellurium Hexafluoride,
2021
University of Tennessee, Knoxville
Production And Adsorption Of Volatile Tellurium Hexafluoride, Stephanie H. Bruffey
Doctoral Dissertations
Research and development supporting the management of off-gases from nuclear fuel reprocessing has historically been focused on the off-gas streams that arise from aqueous reprocessing technology. With the advent of advanced reactor designs off-gas streams arising from advanced reprocessing methodology, such as that of FV [fluoride volatility] processing, also merit consideration. This work focuses on TeF6 [tellurium hexafluoride], one of the most volatile radioactive compounds produced during FV, and investigates TeF6 production, measurement, and abatement technologies.
To assist in on-line monitoring of TeF6 by Fourier-transformed infrared spectroscopy, this work systematically used the ideal gas law and Beer’s …
Ultrasound-Driven Fabrication Of Nanosized High-Entropy Materials For Heterogeneous Catalysis,
2021
University of Tennessee, Knoxville
Ultrasound-Driven Fabrication Of Nanosized High-Entropy Materials For Heterogeneous Catalysis, Francis Uchenna Okejiri
Doctoral Dissertations
High-entropy materials (HEMs) have emerged as a new class of multi-principal-element materials with great technological prospects. As a unique class of concentrated solid-solution materials, HEMs, formed on the premise of incorporating five or more principal elements into a single crystalline phase, provide an excellent opportunity to access superior catalytic materials ‘hiding’ in the unexplored central regions of a multicomponent phase space of higher orders.
However, the fabrication of HEMs is energy-intensive, typically requiring extreme temperatures and/or pressures under which agglomeration of particles occurs with a commensurate decrease in surface area. For most catalytic applications, non-agglomerated particles with high surface areas …
Rational Design Of Multifunctional Nanocatalysts For Environmental Remediation And Energy Conversion Technologies,
2021
University of Texas at El Paso
Rational Design Of Multifunctional Nanocatalysts For Environmental Remediation And Energy Conversion Technologies, Md Ariful Ahsan
Open Access Theses & Dissertations
The discovery of efficient and sustainable carbon-based nanotechnologies to solve both the scarcity of drinking water and global energy crisis has become a paramount task in the last decades. Owed to the fast population growth and industrialization of the modern society, access to potable water and clean energy technologies is becoming very hard around the globe. Water pollutants have become a serious threat to the environment and ecology because of their toxic nature. Parallelly, the current hydrocarbon-based fuel industries are generating high levels of contamination across the planet, making imperative the development of cleaner energy technologies. In this regard, the …
Exploring The Potential Use Of Porous Silica Nanoparticles In Cest-Mri,
2021
Portland State University
Exploring The Potential Use Of Porous Silica Nanoparticles In Cest-Mri, Lydia Makotamo
Dissertations and Theses
Magnetic resonance imaging (MRI) is a widely used modality in diagnostics, treatment, and monitoring various conditions due to its ability to generate high-resolution images using non-ionizing radiation. The advent of contrast agents, which generally work by increasing the spin relaxation rate constants of water protons, has led to image enhancement. Despite the usefulness of this class of agents in diagnostic medicine, their inability to provide in-depth functional and anatomical information, coupled with their high detection limits, has led to new agents being explored.
Chemical exchange saturation transfer (CEST) presents an alternative route to generate signals via repetitive saturations transfers between …