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Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah Jan 2021

Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah

Graduate Theses, Dissertations, and Problem Reports

Valorization of Xylan in Agroforestry Waste Streams.

Harrison Appiah

Microwave-assisted deep eutectic solvent and gamma-valerolactone metallic chloride catalyzed conversion of xylan to furfural were investigated using a 2x3 factorial experimental design at two levels of percent microwave power, reaction time, and catalyst concentration. The levels of each factor studied were (20%, 60% microwave power, 2, 4 minutes, and 10, 20mg) respectively. The effect of three metallic chloride catalysts (LiCl, FeCl3.6H20, CuCl2) on the conversion of xylan to furfural was also investigated. The gamma-valerolactone-ferric chloride sent system exhibited the highest mean yield of furfural (56.50%). The next highest furfural yield of …


Effects Of Different Liquid Smoke Treatments On Osmotic Dehydration Of Apple Cubes, Rohit Singh Jan 2021

Effects Of Different Liquid Smoke Treatments On Osmotic Dehydration Of Apple Cubes, Rohit Singh

Graduate Theses, Dissertations, and Problem Reports

Refined Liquid Smoke (RLS) (1%) was incorporated during osmotic dehydration of apple cubes (10 mm each side) to observe its effect on solid gain, water loss, yield, water activity, product quality, and consumer preference. Three different treatments, POD (pure osmotic dehydration, no RLS), LSISS (RLS inside sugar solution) and PTLS (pre-treatment with RLS), were compared in this study. Osmotic dehydration was carried out using 42 °Brix sugar solution, and the fruit to solution ratio was kept at 1:4. The osmotically dehydrated apples were evaluated for soluble solid content (SSC), water loss, and solid gained. After osmotic dehydration, apple cubes were …


Review Of Forecasting Univariate Time-Series Data With Application To Water-Energy Nexus Studies & Proposal Of Parallel Hybrid Sarima-Ann Model, Cory Sumner Yarrington Jan 2021

Review Of Forecasting Univariate Time-Series Data With Application To Water-Energy Nexus Studies & Proposal Of Parallel Hybrid Sarima-Ann Model, Cory Sumner Yarrington

Graduate Theses, Dissertations, and Problem Reports

The necessary materials for most human activities are water and energy. Integrated analysis to accurately forecast water and energy consumption enables the implementation of efficient short and long-term resource management planning as well as expanding policy and research possibilities for the supportive infrastructure. However, the integral relationship between water and energy (water-energy nexus) poses a difficult problem for modeling. The accessibility and physical overlay of data sets related to water-energy nexus is another main issue for a reliable water-energy consumption forecast. The framework of urban metabolism (UM) uses several types of data to build a global view and highlight issues …


Development Of Multi-Catchment Rating Curves For Streams Of Appalachian Mixed-Land-Use Watersheds: Preliminary Results, Zachary A. Heck Jan 2021

Development Of Multi-Catchment Rating Curves For Streams Of Appalachian Mixed-Land-Use Watersheds: Preliminary Results, Zachary A. Heck

Graduate Theses, Dissertations, and Problem Reports

Anthropogenic activities can alter the quantity and quality of water. Traditional monitoring of streamflow involves measurements of stage (mm), or water height, and discharge (i.e., streamflow) (m3 s -1 ) above a local datum. However, while stage is relatively easily monitored, continuous streamflow measurement is often impractical and prohibitively expensive. To address this challenge, rating curve equations can be developed to convert stage to flow. To establish a series of rating curves for flow estimations in Appalachia, an investigation was conducted in a representative urbanizing, mixed-land-use watershed in north-central West Virginia consisting of 21 nested stream gauge sites. At each …


Can Stable Isotopes From Tree Rings Improve Our Understanding Of Past Variability In The Southern Annular Mode?, Zachary Grzywacz Jan 2021

Can Stable Isotopes From Tree Rings Improve Our Understanding Of Past Variability In The Southern Annular Mode?, Zachary Grzywacz

Graduate Theses, Dissertations, and Problem Reports

Few annually dated stable isotope records exist across Oceania. In mid- to high-latitude locations in South America, tree-ring stable isotopes provide information about past climate dynamics such as the Southern Annular Mode (SAM). The SAM drives latitudinal shifts in Southern Hemisphere westerly winds, influencing temperature and moisture delivery across the mid- to high-latitudes, including Tasmania. Combinations of paleoclimate proxies from across the Southern Ocean might provide insight into dynamic processes like the SAM that are difficult to measure with a single proxy. Measuring stable carbon and oxygen isotope ratios from tree rings in Tasmania could provide complementary data to contribute …


Employing Exoglycosidase And Transferase Enzymes In Capillary Nanogel Electrophoresis For The Determination Of N-Glycan Linkages And Enzyme Michaelis-Menten Constants., Lloyd Bwanali Jan 2021

Employing Exoglycosidase And Transferase Enzymes In Capillary Nanogel Electrophoresis For The Determination Of N-Glycan Linkages And Enzyme Michaelis-Menten Constants., Lloyd Bwanali

Graduate Theses, Dissertations, and Problem Reports

As a post translational modification protein glycosylation plays a crucial role in protein signaling, binding, kinetics and folding. In disease diagnosis and prognosis, monitoring glycosylation has been identified as a biomarker. Sialylation and sialic acid linkage in N-glycans are markers of cancers including liver, pancreatic and kidney cancer. Quantification of sialic acid linkage is analytically challenging because of the diverse linkages and the presence of heterogenous branching. A capillary electrophoresis method is reported that integrates a unique combination of enzymes and lectins to modify sialylated asparagine-linked glycans (N-glycans) in real time in the capillary so that N-glycan structures containing α2–6-linked …


Enhancing Negative-Ion Native Mass Spectrometry With Field-Assisted Capillary Vibrating Sharp-Edge Spray Ionization (Cvssi), Kushani Udeshika Attanayake Jan 2021

Enhancing Negative-Ion Native Mass Spectrometry With Field-Assisted Capillary Vibrating Sharp-Edge Spray Ionization (Cvssi), Kushani Udeshika Attanayake

Graduate Theses, Dissertations, and Problem Reports

Although the birth of native mass spectrometry (native MS) occurred only several years after the development of electrospray ionization (ESI), it is yet considered an emerging technique for MS-based studies. This stems in part from challenges associated with efficient ionization of biopolymers. Although steady gains in ion production for native structure characterization have been secured primarily with the use of nanoelectrospray ionization (nESI), under negative polarity, the ionization efficiency can be extensively reduced due to an effect called “corona discharge”. The corona discharge occurs at the tip of ESI emitters because of free electron acceleration in the high-field region produced …


Equilibrium And Non-Equilibrium Ultrafast Carrier Transport And Dynamics In Chalcopyrite Semiconductors, Rishmali Thanuja Sooriyagoda Jan 2021

Equilibrium And Non-Equilibrium Ultrafast Carrier Transport And Dynamics In Chalcopyrite Semiconductors, Rishmali Thanuja Sooriyagoda

Graduate Theses, Dissertations, and Problem Reports

Chalcopyrite crystals in the II-IV-V2 family have received significant interest due to their high nonlinearity, composition-tunable bandgaps, wide transparency windows, and high damage threshold. These semiconductors have been explored for electromagnetic (EM) screening, spintronic and photovoltaic applications, making them good optical and optoelectronic materials. This thesis uses terahertz spectroscopy to understand optical, electronic, and vibrational dynamical processes in CdGeP2, ZnGeP2 and CdSiP2 chalcopyrite semiconductors.

We have employed Terahertz time-domain spectroscopy to investigate temperature-dependent ground-state properties of bulk chalcopyrite crystals that can be related to electronic transport and electron-lattice interactions. The complex spectra provide refraction and …


Refining The Sedimentology And Geochemistry Of The Mid-Permian Blaine Formation Of The Rebecca K. Bounds Core From Greeley County, Kansas, Brigitte Petras Jan 2021

Refining The Sedimentology And Geochemistry Of The Mid-Permian Blaine Formation Of The Rebecca K. Bounds Core From Greeley County, Kansas, Brigitte Petras

Graduate Theses, Dissertations, and Problem Reports

Red siliciclastics and evaporites of Permian Nippewalla Group in mid-continental US were deposited in western equatorial Pangea. Previous studies of these rocks record Permian air temperatures as high as 73 °C, saline lake waters with a pH as low as ~1, and sedimentology that shows arid conditions. This current study conducts detailed sedimentological observations and geochemical analyses of the Blaine Formation of the Nippewalla Group. The Rebecca K. Bounds core from west-central Kansas is used to interpret the depositional environments and diagenetic history of the Blaine Formation.

The lithologies of the Blaine Formation, listed in order of most to least …


Planning Algorithms Under Uncertainty For A Team Of A Uav And A Ugv For Underground Exploration, Matteo De Petrillo Jan 2021

Planning Algorithms Under Uncertainty For A Team Of A Uav And A Ugv For Underground Exploration, Matteo De Petrillo

Graduate Theses, Dissertations, and Problem Reports

Robots’ autonomy has been studied for decades in different environments, but only recently, thanks to the advance in technology and interests, robots for underground exploration gained more attention. Due to the many challenges that any robot must face in such harsh environments, this remains an challenging and complex problem to solve.

As technology became cheaper and more accessible, the use of robots for underground ex- ploration increased. One of the main challenges is concerned with robot localization, which is not easily provided by any Global Navigation Services System (GNSS). Many developments have been achieved for indoor mobile ground robots, making …


Ecology Of Freshwater Turtles And Other Wetland Wildlife In A North-Central West Virginia Watershed, Darien N. Lozon Jan 2021

Ecology Of Freshwater Turtles And Other Wetland Wildlife In A North-Central West Virginia Watershed, Darien N. Lozon

Graduate Theses, Dissertations, and Problem Reports

The goal of wetland mitigation in the United States is to achieve a no-net-loss of wetlands; however, mitigated wetlands must be monitored to ensure wetland function is comparable to natural wetlands. In this study, relationships between land use practices and freshwater turtle abundance, wetland connectivity, and heavy metal bioaccumulation were investigated. In Chapter 1, a summary of pre-restoration species abundance and diversity is provided for anurans, birds, benthic macroinvertebrates, fishes, small mammals, plants, and turtles in riparian wetlands along Ruby Run, a tributary of Deckers Creek in north-central West Virginia, USA. These data provide a baseline for comparison after mitigation …


Soil Response Of Helicopter Liming In The Monongahela National Forest, Jarrett Douglas Fowler Jan 2021

Soil Response Of Helicopter Liming In The Monongahela National Forest, Jarrett Douglas Fowler

Graduate Theses, Dissertations, and Problem Reports

Soils in the Monongahela National Forest (MNF) are acidic due to sandstone parent material, acid deposition, uptake of base cations by vegetation, and release of organic acids by organic matter (OM) decomposition. Increases in soil acidity have caused declines in forest health and changed species composition and nutrient status. Liming can neutralize soil acidity, but no large-scale liming projects have been done on acid forest soils in the USA. In anticipation of acquiring funding for a proposed liming project in the MNF, in 2007 and 2009 10 sites were selected to sample and analyze soils before lime was applied. In …


Majorana Nanostructures And Their Electrostatic Environment, Benjamin David Woods Jan 2021

Majorana Nanostructures And Their Electrostatic Environment, Benjamin David Woods

Graduate Theses, Dissertations, and Problem Reports

Majorana zero modes (MZMs) are zero-energy excitations emerging in one- and two-dimensional topological superconductors. These exotic modes have attracted much attention in the last decade due to their topological protection and non-Abelian statistics, which make them possible building blocks for topological quantum computation. In particular, semiconductor-superconductor (SM-SC) nanostructures have attracted the most attention with several measurements being consistent with the presence of MZMs. Debate continues, however, whether MZMs or topologically-trivial Andreev bound states are responsible for such measurements.

In order to interpret experimental results distinguishing MZMs from Andreev bound states and gain a better understanding of what conditions need to …


Development Of Vibrating Sharp-Edge Spray Ionization (Vssi) Methods For Mass Spectrometry Analysis And Imaging, Nandhini Ranganathan Jan 2021

Development Of Vibrating Sharp-Edge Spray Ionization (Vssi) Methods For Mass Spectrometry Analysis And Imaging, Nandhini Ranganathan

Graduate Theses, Dissertations, and Problem Reports

Mass Spectrometry (MS) is one of the widely used tools for chemical detection down to attomole concentrations for certain proteins. Ionization sources are a critical component for MS analysis. One of the major ionization methods is electrospray ionization (ESI), which remains a gold standard for proteins and peptides. ESI uses voltages up to ~4 kV to produce ions from solubilized molecules. Recently, a novel ionization method termed vibrating sharp-edge spray ionization (VSSI) that nebulizes liquids efficiently at the edge of a vibrating glass slide has been reported. The work in this thesis leverages the capabilities of VSSI for continuous flow-based …


Deep Fingerprint Matching From Contactless To Contact Fingerprints For Increased Interoperability, Alexander James Wilson Jan 2021

Deep Fingerprint Matching From Contactless To Contact Fingerprints For Increased Interoperability, Alexander James Wilson

Graduate Theses, Dissertations, and Problem Reports

Contactless fingerprint matching is a common form of biometric security today. Most smartphones and associated apps now let users opt into using this form of biometric security. However, it’s difficult to match a finger-photo to a fingerprint because of perspective distortion occurring at the edges of the finger-photo, so direct matching using conventional methods will not be as accurate due to a lack of sufficient matching minutiae points. To address this issue, we propose a deep model, Perspective Distortion Rectification Model (PDRM), to estimate the fingerprint correspondence for finger-photo images in order to recover more minutiae points. Not only do …


Examining West Virginia's Economic Development: Natural Resources, Development Agencies, And Labor Force Development, Gaillynn Marie Bowman Jan 2021

Examining West Virginia's Economic Development: Natural Resources, Development Agencies, And Labor Force Development, Gaillynn Marie Bowman

Graduate Theses, Dissertations, and Problem Reports

Examining West Virginia's Economic Development: Natural Resources, Development Agencies, and Labor Force Development Gaillynn Bowman Economic development is well-recognized as being fundamental to facilitating an overall improved quality of life for communities and their residents. Throughout West Virginia’s history, the state has experienced economic hardships caused by boom and bust cycles associated with resource extraction. This dissertation consists of three essays that explore the impacts of economic development activities, including conservation programs, economic development agency initiatives, and workforce development agencies. The first essay explores the relationship nonresident landowners have with the conservation programs within West Virginia, specifically the Natural Resources …


Biocompatible And Multifunctional Trityl Spin Probes For Electron Paramagnetic Resonance Spectroscopy, Teresa D. Gluth Jan 2021

Biocompatible And Multifunctional Trityl Spin Probes For Electron Paramagnetic Resonance Spectroscopy, Teresa D. Gluth

Graduate Theses, Dissertations, and Problem Reports

The primary objective of my thesis was to develop and utilize a biocompatible multifunctional trityl spin probe for concurrent measurement of pO2, pHe, and [Pi] in vivo by electron paramagnetic resonance (EPR) spectroscopy (Chapter 2). My first goal was to synthesize the proposed probe we are terming HOPE71. Secondly, HOPE71 was characterized by X-band and L-band EPR spectroscopy. Next, the biocompatibility of HOPE71 was assessed through an albumin binding test, cytotoxicity assays, and in vivo intravenous tolerance. Then, the use of HOPE71 to measure the target parameters was demonstrated in a breast cancer …


Analysis And Classification Of Software Fault-Proneness And Vulnerabilities, Mohammad Jamil Ahmad Jan 2021

Analysis And Classification Of Software Fault-Proneness And Vulnerabilities, Mohammad Jamil Ahmad

Graduate Theses, Dissertations, and Problem Reports

Software bugs are expensive to fix and can lead to catastrophic consequences. Therefore, their analysis and the use of machine learning for prediction are of the utmost importance. Many prediction models have been proposed and different factors affecting the prediction performance have been extensively studied. This work addresses four topics in two areas in software engineering: software fault-proneness prediction and analysis and classification of security-related bug reports. The first topic focuses on the effect of the learning approach (i.e., the way software fault-proneness prediction models are trained and tested) on the performance of software fault-proneness prediction which lacks extensive research …


Experimental Investigations Of Contact Friction And Transport Properties Of Monolayer And Bilayer Graphene, Prakash Gajurel Jan 2021

Experimental Investigations Of Contact Friction And Transport Properties Of Monolayer And Bilayer Graphene, Prakash Gajurel

Graduate Theses, Dissertations, and Problem Reports

Results obtained from experimental investigations of contact friction in monolayer and bilayers graphene and the related effects on their transport properties are presented here along with their discussion and interpretation. For this purpose, chemical vapor deposited (CVD) graphene samples on SiO2/Si were prepared. The samples were characterized by atomic force microscopy (AFM), Raman and X-ray photoelectron spectroscopy (XPS). Summaries of the results are given below.

Defects-controlled friction in graphene is of technological importance but the underlying mechanism remains a subject of debate. The new results obtained from the analysis of lateral force microscopy images revealed that the contact …


Application Of 3d Seismic Signal And Geomechanical Attributes For Subsurface Fracture Characterization: A Case Study In Clearfield County, Central Pennsylvania, Iman F. Zulkapeli Jan 2021

Application Of 3d Seismic Signal And Geomechanical Attributes For Subsurface Fracture Characterization: A Case Study In Clearfield County, Central Pennsylvania, Iman F. Zulkapeli

Graduate Theses, Dissertations, and Problem Reports

Hydrocarbon exploration in unconventional reservoirs is highly risky due to the nature of the reservoirs and the variability in fractures and reservoir geomechanical properties in the subsurface. The reservoir needs to be fully characterized to avoid any complication such as frac hit, wellbore failure, blowout, or even a dry hole. The Clearfield reservoir produces an exceptionally low amount of gas, compared to the neighboring region in the proximity, which has been poorly understood. This raises the question as to what causes the reservoir to have low productivity.

This study focuses on the natural fracture characterization using high-quality 3D seismic signal …


Association Of Incident Cancer To Low-Value Care And Healthcare Cost Burden Among Elderly Medicare Beneficiaries, Chibuzo Iloabuchi Jan 2021

Association Of Incident Cancer To Low-Value Care And Healthcare Cost Burden Among Elderly Medicare Beneficiaries, Chibuzo Iloabuchi

Graduate Theses, Dissertations, and Problem Reports

In the United States (US), 25% of healthcare spending is considered wasteful because it is spent reimbursing low-value care. Low-value care is the utilization of healthcare services, medical tests, and procedures that have unclear or no clinical benefit to patients but still exposes them to risk. World-wide, low-value care imposes a significant economic burden on patients, payers, governments, and society. Cancer care among older adults > 65 years is one of the biggest drivers of healthcare expenditure in the US and accounts for nearly 40% of all spending, and low-value care among cancer patients is prevalent and contributes to the financial …


Variations In Produced Water Chemistry And Relation To Regional Geology And Production In The Marcellus Shale, Northcentral West Virginia, Jonathan M. Brady Jan 2021

Variations In Produced Water Chemistry And Relation To Regional Geology And Production In The Marcellus Shale, Northcentral West Virginia, Jonathan M. Brady

Graduate Theses, Dissertations, and Problem Reports

An investigation of 74 Marcellus Shale wells across northcentral West Virginia indicates changes in produced water chemistry and quantity can be related to geologic conditions based on well logs and core data. These changes are determined by reviewing multiple produced water analyses for individual wells for periods up to ten years. Results show variations among the areas in this study. From west to east across central Harrison County to central Taylor County, then north into Monongalia County, gamma-ray logs show increasing intensity, especially in the middle and lower Marcellus. XRD mineralogy from core data shows increasing clay content from west …


Effect Of Oxidative Breakers On Organic Matter Degradation, Contaminant Mobility And Critical Mineral Release During Shale-Fracturing Fluid Interactions In The Marcellus Shale, Shaun Donmoyer Jan 2021

Effect Of Oxidative Breakers On Organic Matter Degradation, Contaminant Mobility And Critical Mineral Release During Shale-Fracturing Fluid Interactions In The Marcellus Shale, Shaun Donmoyer

Graduate Theses, Dissertations, and Problem Reports

Production of oil and gas from organic-rich shale formations has become viable through advancements in multi-stage hydraulic fracturing. The decline of shale gas production after the initial days of fracturing operations coupled with falling oil and gas prices, has pushed industry operators to use new chemical additives as an attempt to increase hydrocarbon production. The implementation of highly reactive fracturing fluids that include strong oxidizing agents, pose as a potential solution to increase well productivity. Strong oxidizing chemicals commonly known in fracturing operations as breakers, are used to improve the viscosity of gel-based fluids after the proppant is transported into …


Improving Characterization Of Small Molecules Using Enhanced Molecular Reaction And Ionization Techniques, Sandra N. Majuta Jan 2021

Improving Characterization Of Small Molecules Using Enhanced Molecular Reaction And Ionization Techniques, Sandra N. Majuta

Graduate Theses, Dissertations, and Problem Reports

Metabolomics is an emerging “omics” field, which is comprised of the study of small molecule metabolites in biological systems. It can be argued that the abundances of metabolites within biological samples, such as tissue and plasma, are indicative of various physiological states. Thus, metabolomics analysis has the potential in the clinical scientific field to be an effective tool for early disease diagnosis as well as for proposing and monitoring new treatments for diseases. However, full characterization of the metabolome complement is often hampered by the wide diversity of metabolites, which also exhibit an extremely large concentration range in biological samples. …


Photochemical Motion Control Of Belousov-Zhabotinsky Droplets And Turbulence-Like Patterns In The Aluminum Hydroxide Precipitation System, Syed Jazli Syed Jamaluddin Jan 2021

Photochemical Motion Control Of Belousov-Zhabotinsky Droplets And Turbulence-Like Patterns In The Aluminum Hydroxide Precipitation System, Syed Jazli Syed Jamaluddin

Graduate Theses, Dissertations, and Problem Reports

A Belousov-Zhabotinsky (BZ) droplet that is immersed in an oil-phase can self-propel due to a surface tension gradient that exists on the droplet surface. The surface tension gradient is created as a result of the reactions that occur within and on the surface of the BZ droplet. By affecting the rates of these reactions, the BZ droplet direction can be controlled. In our experiments, we tune the reactions that occur within and on the BZ droplet surface by imposing a light intensity gradient on the droplet. We analyzed the BZ droplet motion and demonstrated that we can control the droplet …


Enabling Technologies For Medicinal Chemistry And Synthesis: I. Cannabinoids; Ii. Illudalic Acid; Iii. Microwave Chemistry, Harvey Fulo Jan 2021

Enabling Technologies For Medicinal Chemistry And Synthesis: I. Cannabinoids; Ii. Illudalic Acid; Iii. Microwave Chemistry, Harvey Fulo

Graduate Theses, Dissertations, and Problem Reports

Innovations in synthetic organic chemistry such as methodology improvements, new chemical transformations and technology development significantly impact medicinal chemistry and continue to drive the drug discovery process. Here, new cyclization strategies to the pharmaceutically underexplored 3,3-dimethylcyclopentane-fused aromatic rings are described. One approach highlighted oxidative cycloisomerization, intermolecular [2+2+2] cyclotrimerization and 5-exo-dig cyclization providing indanoylindole cannabinoids that possess high affinity for human CB2 receptors at nanomolar concentration and good selectivity index. Another featured a [4+2]-type benzannulation reaction which enabled the 5-step synthesis of illudalic acid — compared to the current available sequences (≥16 steps) — and its equipotent and LAR-selective analogs. …


Analysis Of Cell Signaling Perturbations In Response To Chronic Localized Infections, Amber Nicole Prince Jan 2021

Analysis Of Cell Signaling Perturbations In Response To Chronic Localized Infections, Amber Nicole Prince

Graduate Theses, Dissertations, and Problem Reports

The tissue-level response to pathogens involves an intricate series of signal transduction events, influenced by immune and healing mediators that alert the host to danger and eliminate the infection. Disruptions to normal signaling events can compromise the host’s ability to respond and lead to the development of chronic infections that cannot be resolved without clinical intervention. Prolonged inflammation due to chronic infection can damage tissues and compromise healing processes, thus, the interactions of immune and healing mediators in signaling cascades are intimately linked to tissue health outcomes. Studying signaling networks relevant to these responses provided a more thorough understanding of …


Single And Multi-Photon Laser Induced Fluorescence For Electric Thruster And Fusion Applications, Thomas E. Steinberger Jan 2021

Single And Multi-Photon Laser Induced Fluorescence For Electric Thruster And Fusion Applications, Thomas E. Steinberger

Graduate Theses, Dissertations, and Problem Reports

Single and Multi-photon Laser Induced Fluorescence for Electric Thruster and Fusion Applications

Thomas Edward Steinberger

Laser-based diagnostics are increasingly sought after to investigate a variety of plasmas due to their non-perturbative capabilities. Specifically, laser induced fluorescence (LIF) provides a highly localized and precise spectroscopic technique to measure absolute density, temperature, and bulk flow. In this work, LIF and two-photon absorption laser induced fluorescence (TALIF) are used to investigate electric propulsion and fusion-relevant plasmas, respectively. Ion velocity distribution functions (IVDF) of singly ionized atomic iodine (I II) are measured for the first time and lineshape characteristics are presented for the diagnosis …


Pulsar Noise Processes And Emission Physics, Brent Jacob Shapiro-Albert Jan 2021

Pulsar Noise Processes And Emission Physics, Brent Jacob Shapiro-Albert

Graduate Theses, Dissertations, and Problem Reports

Precision pulsar timing can be used to study many different astrophysically interesting phenomena, from the emission mechanism of pulsars to the detection of nanohertz gravitational waves. These analyses span topics such as studying the single pulses of pulsars and analyzing years of pulsar timing data from pulsar timing arrays (PTAs). Single-pulse studies allow us to glean information on the emission physics of pulsars on their shortest timescales, while PTA observations of millisecond pulsars (MSPs) allow us to not only study the pulsars themselves, but also probe the interstellar medium (ISM) and constrain the noise in the data for precision pulsar …


Fundamentals And Applications Of Charge Transfer Dissociation Mass Spectrometry, Zachary Joseph Sasiene Jan 2021

Fundamentals And Applications Of Charge Transfer Dissociation Mass Spectrometry, Zachary Joseph Sasiene

Graduate Theses, Dissertations, and Problem Reports

The recent surge in the analysis of biomolecules has driven the need for robust, versatile, sensitive, and accurate techniques such as tandem mass spectrometry for compound structural elucidation. Many fragmentation techniques have been developed over the years, but each has their own limitations, such as the loss of post-translational modifications (PTMs), inability to fragment singly charged precursor ions or cost prohibitiveness. To help fill this gap, a novel fragmentation technique called charge transfer dissociation (CTD) has been developed to fragment stored precursor ions through radical-driven fragmentation processes using kiloelectronvolt reagent cations. CTD has shown success in the analysis of proteins, …