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Articles 41731 - 41760 of 714488
Full-Text Articles in Entire DC Network
Three Essays On Education And Health Economics, Kalvin Mudrow
Three Essays On Education And Health Economics, Kalvin Mudrow
Graduate Theses, Dissertations, and Problem Reports (ETD)
The first chapter explores the impact of online education on student outcomes by comparing students pre-2020 school closures to students post-2020 school closures. Using student-level panel data from a large U.S. school district spanning 2017-2023 and two outcome variables, reading tests and end-of-level exams, I estimate the effects on different demographic groups, the dynamics of these effects over time, and how these effects differ across students ages. I find a significant decline in student performance after the move to online learning, with additional adverse effects on students who are classified as low-income, female, special education, or ELL. Mechanisms contributing to …
The Origin And Properties Of Ionized Gas In The Inner Milky Way Disk, Dylan J. Linville
The Origin And Properties Of Ionized Gas In The Inner Milky Way Disk, Dylan J. Linville
Graduate Theses, Dissertations, and Problem Reports (ETD)
The interstellar medium (ISM) plays a crucial role in the evolution of the Milky Way and other spiral galaxies, but numerous gaps remain in our collective understanding of its properties. The now-complete Green Bank Telescope (GBT) Diffuse Ionized Gas Survey (GDIGS) and the ongoing extension, the GBT Diffuse Ionized Gas Survey at Low Frequencies (GDIGS-Low), offer the opportunity to study the ionized component of the ISM at unmatched sensitivity and resolution. In this dissertation I will utilize GDIGS and GDIGS-Low data to improve our understanding of discrete regions of ionized gas. I first use GDIGS to provide improved measurements of …
Late Ordovician Evolution Of Sea Scorpions: Eurypterids Of The Big Hill Lagerstätte, Joseph Donaldson Bingham Jr.
Late Ordovician Evolution Of Sea Scorpions: Eurypterids Of The Big Hill Lagerstätte, Joseph Donaldson Bingham Jr.
Graduate Theses, Dissertations, and Problem Reports (ETD)
Eurypterids are a group of diverse chelicerates that first appeared during the Middle Ordovician (467.3 Ma) and went extinct at the end of the Permian (251.9 Ma). The fossil record of eurypterids during the Ordovician is relatively sparce, comprising only 12 species representing the Megalograptidae, a ‘waeringopterid’ clade, Rhenopteridae, Onychopterellidae, Adelophthalmoidea, and Eurypteroidea clades. This study describes early eurypterids from the Katian aged (~452 Ma) Big Hill Lagerstätte of Michigan. The described material represents two new species, herein named Machipterus margaritae sp. nov. (based on 21 specimens preserving the ventral prosoma and prosomal appendages, and opisthosoma) and Dikranopterus lysinae sp. …
Refinement Of A Thermodynamic Model To Explain The Weathering Patterns Of Ignitable Liquids On Household Substrates At Elevated Temperatures, Chaney Ashlyn Ganninger
Refinement Of A Thermodynamic Model To Explain The Weathering Patterns Of Ignitable Liquids On Household Substrates At Elevated Temperatures, Chaney Ashlyn Ganninger
Graduate Theses, Dissertations, and Problem Reports (ETD)
ABSTRACT
Refinement of a thermodynamic model to explain the weathering patterns of ignitable liquids on household substrates at elevated temperatures
Chaney A. Ganninger
In 2021, arson caused more than 4,361 deaths in the United States. To aid in the differentiation between arson and accidental or natural causes, investigators often analyze fire debris for the presence of ignitable liquid residues using headspace concentration followed by gas chromatography-mass spectrometry (GC-MS). Classification of ignitable liquids can be confounded by weathering, which is the uneven evaporation of compounds in ignitable liquid residues. The Jackson group, among others, has developed a thermodynamic model to help …
Exploring Teacher Perception And Implementation Of Sae Programming In West Virginia, Joseph Laflamme
Exploring Teacher Perception And Implementation Of Sae Programming In West Virginia, Joseph Laflamme
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study was to describe the phenomenon of SAE implementation in West Virginia. This study utilized qualitative research methodology to describe teacher perceptions of how student, guardian, school and community factors affect SAE program implementation. Additionally, teacher backgrounds, including formative experiences, training and education, guiding philosophies, skills, and motivation were explored. This study describes contextual aspects of population, economics, state guidelines and local agriculture industries. This is done through a document review of student reported records as well as surveys and teacher interviews.
Augmentation And Hybridization Of Conventional Forms Of Process Control With Advanced Control Methods, Daniel Paul Beahr
Augmentation And Hybridization Of Conventional Forms Of Process Control With Advanced Control Methods, Daniel Paul Beahr
Graduate Theses, Dissertations, and Problem Reports (ETD)
Within the last decade in the field of process control, there has developed a distinct gap between the technological advancements of today and the well-established theory that has preceded it. This is most evident where the novel developments and structures often outpace the necessary guarantees and strong foundation required to ensure the possibility of widespread adoption. Therefore, the goals of this work are to broadly integrate those novel advanced control methods into the field of process control in such a way to increase the applicability and encourage implementation.
The first portion of this work seeks to further explore the nature …
Membrane Reactor Modeling And Optimization For Hydrogen Production, Ayooluwa Tomiwa Akintola
Membrane Reactor Modeling And Optimization For Hydrogen Production, Ayooluwa Tomiwa Akintola
Graduate Theses, Dissertations, and Problem Reports (ETD)
There has been an ongoing trend toward cleaner fuels for more environmentally benign forms of energy generation. Recently, hydrogen has been identified as a clean fuel for energy generation. However, the most established, efficient, and widely utilized technique for producing hydrogen remains the steam methane reforming (SMR) in the presence of catalyst. Unlike other fossil fuels, utilizing methane from natural gas in an SMR process to produce hydrogen emits less, but yet a notable sum of carbon dioxide. Furthermore, the endothermic nature of SMR reactions imply that there is a high energy requirement to obtain a substantial amount of hydrogen …
Development Of Fast And Comprehensive Approaches For Gunshot Residue Interpretation Using Ambient Ionization, Mass Spectrometry, And Microparticle Sampling Studies, Thomas Dimmey Ledergerber
Development Of Fast And Comprehensive Approaches For Gunshot Residue Interpretation Using Ambient Ionization, Mass Spectrometry, And Microparticle Sampling Studies, Thomas Dimmey Ledergerber
Graduate Theses, Dissertations, and Problem Reports (ETD)
The information derived from the forensic examination of gunshot residue (GSR) can be critical during the investigative and trial stages in the criminal justice system. However, the complexity of the GSR deposition, transfer, and persistence mechanisms calls for meticulous handling and identification processes. Novel advances in evidence interpretation and analysis via instrumental methods are current areas of growing interest that must be pushed along the chain from research to practice in a timely manner. Therefore, this research focuses on developing both rapid and comprehensive methods for detecting gunshot residue evidence and effectively communicating its significance to the investigators or trier …
Do Dung Beetles Sink Or Swim: Exploring Dung Beetle Response To Precipitation, Lauren T. Cheshire
Do Dung Beetles Sink Or Swim: Exploring Dung Beetle Response To Precipitation, Lauren T. Cheshire
Graduate Theses, Dissertations, and Problem Reports (ETD)
Global climate change constitutes a major threat to biodiversity and ecosystem services of many taxa. The Mid-Atlantic region of the US is expecting to see an increase in extreme precipitation events and flooding. Dung beetles (Scarabaeinae) can tunnel below the soil surface allowing for water to dissipate into the soil rather than sit on the surface and add to flooding conditions. They also can decrease methane emission by burying dung and reduce outbreaks of pests that prefer the moist environment of dung. They contribute roughly $380 million in ecosystem services annually in the United States, yet their services may be …
Developing Consensus-Based Methods For The Examination And Interpretation Of Contemporary Vehicle, Architectural, And Portable Electronic Device Glasses By Micro-X-Ray Fluorescence Spectrometry, Zachary Bailey Andrews
Developing Consensus-Based Methods For The Examination And Interpretation Of Contemporary Vehicle, Architectural, And Portable Electronic Device Glasses By Micro-X-Ray Fluorescence Spectrometry, Zachary Bailey Andrews
Graduate Theses, Dissertations, and Problem Reports (ETD)
Glass is a trace material that is commonly encountered during investigations of violent crimes. When glass is recovered at crime scenes, it can be used to establish links between suspects, victims, and the scene itself. The most discriminatory form of analysis for glass evidence is elemental analysis, and micro-X-ray fluorescence spectrometry (µXRF) is becoming an increasingly common technique used for this purpose. Recent advances in µXRF technology, such as the introduction of silicon drift detectors (SDD) and improved polycapillary optics are promising in enhancing the capabilities for the examination of glass evidence in forensic investigations. However, along with these advances …
Modeling Energetic Electron Precipitation: Radiation Belt Loss, Its Drivers, And Atmospheric Impacts, Zhi Gu Li
Modeling Energetic Electron Precipitation: Radiation Belt Loss, Its Drivers, And Atmospheric Impacts, Zhi Gu Li
Graduate Theses, Dissertations, and Problem Reports (ETD)
Energetic electrons in the terrestrial outer radiation belt present significant hazards to spacecraft systems and human operations in space. The intensity of these electrons can vary rapidly and dramatically during geomagnetic storms, governed by a complex competition between acceleration and loss processes. Among these, precipitation into the atmosphere via resonant wave-particle interaction acts as a key loss mechanism. This dissertation focuses on improving the quantification of energetic electron precipitation using physics-based modeling constrained by low-altitude satellite observations.
We begin by developing and validating the Drift-Diffusion model, which simulates low-altitude electron dynamics while accounting for azimuthal drift, pitch-angle diffusion, and atmospheric …
Apostrophes And Archimedes, Evan J. Clough
Apostrophes And Archimedes, Evan J. Clough
Graduate Theses, Dissertations, and Problem Reports (ETD)
This thesis explores how digital collage and printmaking can be used to develop images through acts of subjective response, intentional and unintentional acts of appropriation, and parodic re-use and comparison pushed to absurd extremes. It looks at the history of creating art for parodic re-use and examines “Pataphysics”, developed by and for art appropriation of pattern, form, and process. These concepts are explained and related to visual artwork that was made for the thesis exhibition Apostrophes and Archimedes Cast Shadow Puppets. The exhibition invites viewers to experience the phenomenon of observation, automatic transformation, and creation using multiple modalities of exaggerated …
Computational Approaches For Diagnosing Neurological Impairments And Restoring Functional Movement, Serhii Bahdasariants
Computational Approaches For Diagnosing Neurological Impairments And Restoring Functional Movement, Serhii Bahdasariants
Graduate Theses, Dissertations, and Problem Reports (ETD)
Movement is the primary means by which the nervous system converts intention into interaction with the environment. Voluntary limb motion enables standing, walking, reaching, and grasping—actions that underpin self‑care, communication, and economic participation. When diseases or injuries disrupt the pathways that couple neural commands to muscle forces—whether through cortical stroke, spinal cord injury, or peripheral nerve damage—mechanical outcomes such as weakness, loss of coordination, and ultimately reduced mobility emerge. These impairments cascade into secondary complications, increased dependence on caregivers, and diminished quality of life. Quantifying how the lesion alters the mechanics of movement is therefore essential for designing targeted interventions …
Functionalized Carbon Nanohoops: Synthesis, Structural Insights, And Pathways To Carbon Nanobelts, Liu Li
Functionalized Carbon Nanohoops: Synthesis, Structural Insights, And Pathways To Carbon Nanobelts, Liu Li
Graduate Theses, Dissertations, and Problem Reports (ETD)
The development of structurally defined carbon nanostructures has gained significant attention due to their unique electronic, optical, and mechanical properties. Cycloparaphenylenes (CPPs), also known as carbon nanohoops, and carbon nanobelts (CNBs) represent key molecular segments of carbon nanotubes (CNTs), offering a bottom-up approach to precise nanotube construction. This dissertation focuses on the synthesis, structural characterization, and functionalization of CPPs, as well as the development of novel synthetic pathways for CNBs. A series of functionalized CPPs, including [9]-, [12]-, [15]-, and [18]CPPs, were synthesized using a modular approach involving a Diels-Alder adduct formation followed by a Ni(cod)2/bpymediated macrocyclization reaction. The influence …
Efficacy Of Salmonella Surrogate Enterococcus Faecium In Poultry And Mash Broiler Feed, Corey Waitman Coe
Efficacy Of Salmonella Surrogate Enterococcus Faecium In Poultry And Mash Broiler Feed, Corey Waitman Coe
Graduate Theses, Dissertations, and Problem Reports (ETD)
This dissertation investigates the efficacy of Enterococcus faecium as a surrogate for Salmonella in validating thermal inactivation processes during poultry feed manufacturing and meat processing. The research encompassed three studies evaluating microbial kinetics in mash broiler feed, reconstructed ground chicken, and predictive modeling approaches to improve food safety interventions. In the first study, the thermal resistance of nalidixic acid-resistant Salmonella Typhimurium and E. faecium was compared in mash broiler feed heated at 75–95°C. Results demonstrated that E. faecium exhibited significantly greater heat resistance than Salmonella, with longer shoulder times, greater tailing effects, and higher D-values, supporting its use as …
Modeling And Simulation Of Carbon-Neutral Strategies For Methanol Production, Omar Almaraz Barrios
Modeling And Simulation Of Carbon-Neutral Strategies For Methanol Production, Omar Almaraz Barrios
Graduate Theses, Dissertations, and Problem Reports (ETD)
Methanol is a versatile chemical that can be used as a fuel, a solvent, a feedstock for other chemicals, and a hydrogen carrier. Methanol production from natural gas, which is mainly composed of methane, is a well-established process that involves steam reforming, methanol synthesis, and methanol purification. However, this process is energy-intensive and emits large amounts of carbon dioxide, which contributes to global warming and climate change. Therefore, there is a need for alternative methods of methanol production that are more efficient and environmentally friendly. The overall objective of this research is to develop simulation models of two novel methanol …
Artificial Intelligence Approaches For Membrane Fouling Prediction, Yazhou Jiang
Artificial Intelligence Approaches For Membrane Fouling Prediction, Yazhou Jiang
Graduate Theses, Dissertations, and Problem Reports (ETD)
Abstract
Membrane fouling is a persistent and critical challenge in membrane-based separation processes, resulting in reduced performance, higher energy consumption, and increased operational and maintenance costs. Addressing this issue is essential for improving the long-term sustainability and efficiency of membrane systems. This report provides a comprehensive overview of membrane fouling mechanisms—such as organic, inorganic, particulate, and biofouling—and explores the growing role of Artificial Intelligence (AI) in tackling this problem. Specifically, it reviews three widely adopted AI techniques: Artificial Neural Networks (ANN), Fuzzy Logic (FL), and Support Vector Machines (SVM). Each method is examined through a series of literature-based case studies, …
Autonomous Vehicle Supported Mobility Services For Rural Areas, Alvira Ahmed Tasnim
Autonomous Vehicle Supported Mobility Services For Rural Areas, Alvira Ahmed Tasnim
Graduate Theses, Dissertations, and Problem Reports (ETD)
Autonomous Vehicles (AVs) are emerging as a promising mobility solution to address growing transportation demands, particularly unmet traffic demand in rural areas where conventional transit systems often fall short. Rural areas face unique mobility challenges due to dispersed populations, limited infrastructure, and low/no transit coverage. Existing transit services tend to concentrate around dense urban cores, leaving low-demand areas outside underserved. This spatial undercoverage leads to significant mobility gaps for rural residents. This study examines the potential of AV-based ride-sharing services to address these mobility needs by providing flexible, demand-responsive mobility services where fixed-route transit services are either economically or operationally …
Reactive Model-Free Control For Underactuated Vehicles Operating In Resource-Constrained Environments, Austin Lane Sponaugle
Reactive Model-Free Control For Underactuated Vehicles Operating In Resource-Constrained Environments, Austin Lane Sponaugle
Graduate Theses, Dissertations, and Problem Reports (ETD)
Buoyancy-driven, underactuated vehicles offer a compelling solution for long-duration autonomous operations in constrained environments. By leveraging buoyancy to generate lift, these vehicles can remain aloft for extended periods with minimal power requirements, making them well-suited for applications in atmospheric monitoring, planetary exploration, and communications. However, their limited actuation authority, strong coupling with environmental forces, and operating domains introduce significant control challenges, including nonlinearity, sensitivity to external disturbances, and limited observability.
This work investigates the design and implementation of lightweight, reactive model-free control strategies that enable robust autonomy in such constrained settings. A digital Extremum Seeking Controller (ESC) is first implemented …
Individual And Collective Properties Of Tunable Photochemical Belousov-Zhabotinsky Micro-Reactors, Kudakwashe Benedict Shumba
Individual And Collective Properties Of Tunable Photochemical Belousov-Zhabotinsky Micro-Reactors, Kudakwashe Benedict Shumba
Graduate Theses, Dissertations, and Problem Reports (ETD)
Cell-like model chemical systems are powerful tools that can be used to explore the role of intercellular coupling on population level behaviors in communities of biological cells. Firstly, we present a new method for fabricating such micro-reactors using the photosensitive Belousov–Zhabotinsky (BZ) reaction system employed in silica microparticles. These BZ micro-reactors have a tunable response to photochemical coupling, varying from a fully excitatory response to a fully inhibitory response. Their response can be tuned through variations in either the reactive mixture or, on an individual micro-reactor level, by changes in the synthesis temperature used during the fabrication of the silica …
From Bobcat To Bursts: Multi-Messenger Constraints On Supermassive Black Holes And Binaries, Jessica Sydnor
From Bobcat To Bursts: Multi-Messenger Constraints On Supermassive Black Holes And Binaries, Jessica Sydnor
Graduate Theses, Dissertations, and Problem Reports (ETD)
Supermassive black hole binaries (SMBHBs) are a natural consequence of hierarchical galaxy formation and evolution. When galaxies merge, their central supermassive black holes (SMBHs) are expected to form bound pairs that evolve from kiloparsec to sub-parsec separations under the influence of dynamical friction, stellar scattering, and gas dynamics. Ultimately, these SMBHs reach the regime where gravitational wave emission dominates and drives the final inspiral and coalescence. Understanding the formation, evolution, and observational signatures of SMBHBs is critical to advancing multi-messenger astrophysics, particularly in the era of pulsar timing arrays (PTAs) and the upcoming Laser Interferometer Space Antenna (LISA), which opens …
Introduction Of Polar Functional Groups To Pyridinedipyrrolide Zirconium Photosensitizers Through Post-Synthetic Modifications, Marisa Nicole Tordella
Introduction Of Polar Functional Groups To Pyridinedipyrrolide Zirconium Photosensitizers Through Post-Synthetic Modifications, Marisa Nicole Tordella
Graduate Theses, Dissertations, and Problem Reports (ETD)
Photosensitizers are vital components to applications such as photoredox catalysis, photodynamic therapy, and various avenues of solar energy production. The abilities of transition metal photosensitizers containing precious metals have been well studied over the years. However, because of the growing scarcity of these metals, there has been a shift in finding more earth abundant alternatives. To help fill this gap in the literature, the Milsmann group has developed and studied the photophysical properties of Zr(IV) complexes with various ligand systems. Due to the electron deficient metal center, these complexes exhibit ligand-to-metal charge transfer (LMCT), unlike the metal-to-ligand charge transfer commonly …
Investigation Of Spalling Effects On The Brittle Behavior Of Rectangular Pillars In Underground Stone Mines, Yolver Yesid Jimenez Ibanez
Investigation Of Spalling Effects On The Brittle Behavior Of Rectangular Pillars In Underground Stone Mines, Yolver Yesid Jimenez Ibanez
Graduate Theses, Dissertations, and Problem Reports (ETD)
Recent catastrophic collapses in U.S. limestone mines have exposed the limitations of traditional empirical design formulas for brittle rock masses. These events, especially those involving slender pillars, underscore that traditional methods often fail to account for progressive, spalling-dominated failure, highlighting a crucial gap in our understanding. This research addresses this issue by conducting a comprehensive investigation into the mechanics of spalling in rectangular stone mine pillars, utilizing advanced three-dimensional numerical modeling with FLAC3D combined with LiDAR-based geometric modeling.
The stability of a pillar is governed by a complex interaction between the in-situ stress field, rock mass properties, and pillar geometry. …
Systematic Methodologies For Magnetic Materials Design, Andres Tellez Mora
Systematic Methodologies For Magnetic Materials Design, Andres Tellez Mora
Graduate Theses, Dissertations, and Problem Reports (ETD)
Understanding and predicting the magnetic behavior of materials from first principles is one of the central challenges in condensed matter physics. This dissertation presents a systematic framework that bridges ab initio calculations, many-body physics, and effective spin models to analyze magnetic materials in particular, but also more general quantum systems. Starting from the electron many-body Hamiltonian and the second quantization formalism, we derive Density Functional Theory (DFT) and explain how magnetic properties emerge from exchange interactions and can be interpreted as perturbations to the magnetization density. To capture these effects efficiently, we construct Heisenberg models from first principles using the …
Optical Measurements Of Magnetic Fields In Low-Temperature Plasmas Via Quantum Spectroscopy, Tyler James Gilbert
Optical Measurements Of Magnetic Fields In Low-Temperature Plasmas Via Quantum Spectroscopy, Tyler James Gilbert
Graduate Theses, Dissertations, and Problem Reports (ETD)
Accurate characterization of the magnetic field strength and direction within a plasma is increasingly important as experiments attempt to probe the physics of plasmas at kinetic scales. Non-perturbative laser-based diagnostics which are spatially and temporally localized—such as laser-induced fluorescence (LIF) and Thomson scattering for the measurement of ion and electron distribution functions, respectively—are increasingly relied on for measurements in laboratory plasmas. This work seeks to develop a spatially and temporally localized non-perturbative laser-based diagnostic for the measurement of magnetic fields in laboratory-relevant plasmas. Two such techniques are investigated here: Zeeman-split LIF and quantum beat spectroscopy (QBS).
Zeeman-split LIF measures the …
Determination Of Spatial Origin Of Striations On Fired Projectiles, Kaitlin A. Dolan
Determination Of Spatial Origin Of Striations On Fired Projectiles, Kaitlin A. Dolan
Graduate Theses, Dissertations, and Problem Reports (ETD)
Firearms examination has been a mainstay of Forensic Science for over a century. One of the principal assessments performed by firearm examiners is the comparison of fired projectiles to a suspect firearm. The AFTE theory of identification, as it pertains to firearms and toolmarks, supports the basis that the barrel of a firearm will impart class and individualizing characteristics onto the fired projectile. The characteristics are developed by the interaction of the projectile surface with the lands of the barrel. Features on the lands, which are incidental to the process of manufacturing, dictate the characteristics observed on the fired projectile. …
Simulation Of Annpet For Neural Network Training And System Performance Benchmarking, Pete Martone
Simulation Of Annpet For Neural Network Training And System Performance Benchmarking, Pete Martone
Graduate Theses, Dissertations, and Problem Reports (ETD)
Monte Carlo (MC) simulations are often used to provide insight into complex physical phenomenon. They can generate realistic results without the necessity to construct costly and complex apparatus. The ultimate value of these simulations depend on how accurately the physics can be modeled and if a sufficient volume can be produced to account for statistical variance. In medical imaging device development, MC simulations of Positron Emission Tomography (PET) scanners have typically been used to model the performance of new systems. The imaging group in the Department of Radiology have developed a unique detector design for a pre- clinical PET scanner …
Neural Network-Based Image Compression, Atefeh Khoshkhahtinat
Neural Network-Based Image Compression, Atefeh Khoshkhahtinat
Graduate Theses, Dissertations, and Problem Reports (ETD)
The rapid advancement of information technology and the exponential growth of digital communication have significantly increased the demand for efficient data compression techniques that reduce storage requirements, minimize bandwidth consumption, and accelerate data transmission—without substantially compromising data quality. This dissertation addresses these challenges by investigating and developing advanced learned image compression (LIC) methods, with a particular focus on lossy compression for both natural images and scientific imagery obtained from NASA’s Solar Dynamics Observatory (SDO) mission. Traditional image compression standards—such as JPEG, JPEG2000, BPG, and HEVC—rely on manually engineered transforms and heuristic rules, which often lack the adaptability required to accommodate …
Assessing And Predicting The Impact Of A Retrofitted Methane Mitigator On Non-Road Large Natural Gas Engines Using Artificial Neural Networks, Augustine Thomas Ojo
Assessing And Predicting The Impact Of A Retrofitted Methane Mitigator On Non-Road Large Natural Gas Engines Using Artificial Neural Networks, Augustine Thomas Ojo
Graduate Theses, Dissertations, and Problem Reports (ETD)
Abstract
ASSESSING AND PREDICTING THE IMPACT OF A RETROFITTED METHANE MITIGATOR ON NON-ROAD LARGE NATURAL GAS ENGINES USING ARTIFICIAL NEURAL NETWORKS
Augustine Thomas Ojo
Methane emissions from the oil and gas sector present a pressing environmental and economic challenge, given methane’s high global warming potential and the considerable volumes of unutilized gas lost from industrial processes. This study investigates the impact of a retrofitted methane mitigation system, the Methane Mitigator (M²), on fuel consumption and engine-out emissions in non-road, four-stroke natural gas-powered, lean-burn engines and develops predictive Artificial Neural Network (ANN) models to estimate the resulting engine-out emissions and fuel …
Development And Applications Of Capillary Vibrating Sharp-Edge Spray Ionization Coupled With Atmospheric Pressure Chemical Ionization (Cvssi-Apci), Madison Elizabeth Pursell
Development And Applications Of Capillary Vibrating Sharp-Edge Spray Ionization Coupled With Atmospheric Pressure Chemical Ionization (Cvssi-Apci), Madison Elizabeth Pursell
Graduate Theses, Dissertations, and Problem Reports (ETD)
Mass spectrometry (MS) is a technique that is used in fields in which both complex and non-complex mixtures are analyzed. The state-of-the-art ion sources that are utilized for MS are being demonstrated to be functional for direct infusion of samples as well as for use with online separations. However, ion sources, such as electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) can encounter problems such as ion suppression and an inability to ionize based on size and/or polarity, respectively. Further these sources are bulky and require gas flow, heat sources, and additional high voltage power supplies for optimal performance. …