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The Investor Perspective Of Materiality, Sam Lessinger Jan 2026

The Investor Perspective Of Materiality, Sam Lessinger

Honors Undergraduate Theses

Often auditors are asked to adopt the reasonable investor perspective in their materiality evaluations however, there is no consensus regarding what investors deem to be material. This can lead to confusion in the markets. In fact, past studies have shown how taking an investor perspective can backfire and may result in more leniency and fewer misstatements being deemed material by auditors. This leniency can, potentially, result in financial statements that mislead investors. The aim of this paper is to address the reasonable investor perspective to achieve a more complete understanding of an investor’s viewpoint. This study also incorporates the effect …


A Framework For Optimizing Creep Model Parameters From Conventional And Accelerated Creep Tests, William D. Day Jan 2026

A Framework For Optimizing Creep Model Parameters From Conventional And Accelerated Creep Tests, William D. Day

Graduate Studies Theses and Dissertations 2026

The demand for efficiency in power generation and propulsion requires higher firing temperatures and reduced cooling air consumption which raises metal temperatures. This makes simplistic creep evaluations, such as Larson-Miller and Orr-Sherby-Dorn parameters, inadequate. Finite element analysis (FEA) must simulate primary and secondary creep, predict failure, and provide design guidance. Gas turbine components, expected to last over 100,000 hours, often require extrapolation of limited test data for new materials. It is essential that robust creep simulations be developed efficiently, accurately, and effectively use limited test data.

This dissertation describes an optimized framework for efficient creep testing and rapid construction of …


Temporal Patterns Of Storm Surges: Event-Identification, Clustering, And Count Modeling, Ariadna Martin Oliva Jan 2026

Temporal Patterns Of Storm Surges: Event-Identification, Clustering, And Count Modeling, Ariadna Martin Oliva

Graduate Studies Theses and Dissertations 2026

Coastal regions face compounding risks when extreme events strike in rapid succession, yet most statistical frameworks treat such events as independent, a simplification that can critically underestimate hazard. This thesis addresses that gap through three interconnected contributions focused on the temporal clustering of storm surges at the global scale. A new automated method is developed to extract independent storm surge events from continuous tide gauge records. By leveraging event correlations and a soft-margin approach that accounts for local variability, the method identifies characteristic event durations across 1,485 global tide gauge stations, revealing the influence of both local site conditions and …


Advancing Multi-Modal Learning, Swetha Sirnam Jan 2026

Advancing Multi-Modal Learning, Swetha Sirnam

Graduate Studies Theses and Dissertations 2026

Multimodal learning aims to develop systems that understand and reason across multiple sources of information such as images, videos, audio, and text. These capabilities are central to applications including visual search, digital assistants, robotics, and visual question answering. Despite recent progress in multimodal large language models, current approaches struggle to capture the structured complexity of real-world visual data. Fine-grained visual details are often lost during multimodal alignment, models frequently fail to capture nuanced human intent, and existing methods remain limited in understanding long-form videos with complex temporal dynamics. Furthermore, many evaluation benchmarks rely heavily on explicit visual cues, which can …


Computational Regolith Mechanics And Instrumentation Development For Lunar Exploration And Resource Utilization, Jared M. Long-Fox Jan 2026

Computational Regolith Mechanics And Instrumentation Development For Lunar Exploration And Resource Utilization, Jared M. Long-Fox

Graduate Studies Theses and Dissertations 2026

Sustained exploration of the Moon requires quantitative understanding of lunar regolith properties to support scientific investigation, in situ resource utilization, excavation, and infrastructure development. This dissertation examines the mechanical interaction between robotic excavation systems and lunar regolith, emphasizing how regolith behavior both enables and constrains exploration-focused and exploration-enabled science. Computational excavation models were compared to laboratory data to evaluate prediction of excavation forces and to develop metrics of excavation efficiency. Laboratory experiments using high-fidelity lunar regolith simulants were conducted to characterize pressure-sinkage behavior, shear strength, and angle of repose across a range of material states. Common analytical excavation and terramechanics …


An Investigation Into The Impact Of Open Educational Resources (Oer) On Postsecondary Student Outcomes, Amber Mullens Jan 2026

An Investigation Into The Impact Of Open Educational Resources (Oer) On Postsecondary Student Outcomes, Amber Mullens

Graduate Studies Theses and Dissertations 2026

Increasing higher education costs are a concern for policymakers and the American public. In 2024-25, undergraduate students paid on average $1,290 for books and supplies (College Board, 2024). These costs have led policymakers and educators to advocate for the use of open educational resources (OER). OER are teaching and learning materials that are in the public domain or licensed under copyright allowing no cost access, reuse, repurpose, adaptation, and redistribution (UNESCO, 2019, p. 5). While research has demonstrated OER use significantly reduces costs for students, less is known about OER's impact on student academic outcomes. Despite significant research on these …


Design And Characterization Of A Jet Nozzle Using Particle Image Velocimetry, Valerie K. Rodriguez Jan 2026

Design And Characterization Of A Jet Nozzle Using Particle Image Velocimetry, Valerie K. Rodriguez

Graduate Studies Theses and Dissertations 2026

This paper presents the design and experimental characterization of the jet exit velocity from a supersonic nozzle injecting into a low-pressure vacuum chamber using Particle Image Velocimetry (PIV). The PIV method is employed to overcome limitations encountered in prior experiments characterizing a jet-in-crossflow, such as qualitative shock visualization and insufficient data on jet exit properties. The previous set of experiments used Classical Schlieren to visualize the flow as well as emission measurement with IR detectors. For the fuel injection cases, particular emphasis is placed on preventing condensation within the injection line and at the nozzle exit due to under expanded …


Watch Your Step, Mind The Crowd: Socially Compliant Navigation In Unstructured Environments, Jack Vice Jan 2026

Watch Your Step, Mind The Crowd: Socially Compliant Navigation In Unstructured Environments, Jack Vice

Graduate Studies Theses and Dissertations 2026

Autonomous mobile robots increasingly operate in complex real-world environments characterized by uneven terrain, dynamic obstacles, and human presence. This dissertation addresses the fundamental challenge of developing adaptive navigation strategies that enable robots to safely and effectively traverse unstructured outdoor environments including construction sites, agricultural fields, and disaster areas while maintaining social compliance around people. We advance this capability through five complementary contributions that collectively target dynamic, unstructured, human-occupied environments. First, we demonstrate evolutionary optimization of legged mobility for uneven terrain. Second, we propose using a spatiotemporal autoencoder to learn the temporal dynamics of moving people and objects. Third, we introduce …


Federated Learning In The Era Of Foundation Models, Guangyu Sun Jan 2026

Federated Learning In The Era Of Foundation Models, Guangyu Sun

Graduate Studies Theses and Dissertations 2026

The emergence of large-scale foundation models has reshaped computer vision and multi-modal learning, but their substantial computational and communication demands pose significant challenges for deployment in federated learning (FL) systems. Federated learning enables collaborative model training across decentralized clients without sharing raw data, offering strong privacy guarantees. However, adapting foundation models in FL remains difficult due to communication bottlenecks, heterogeneous data distributions, limited device resources, and scarce labeled data. This dissertation presents a unified line of research that addresses these challenges through four complementary frameworks, progressively advancing the efficiency, personalization, and practicality of foundation model adaptation in federated settings.

First, …


A Reconstruction Method For The Anisotropic Electrical Conductivity In A Hybrid Planar Inverse Problem, Athanasios Dimitriadis Jan 2026

A Reconstruction Method For The Anisotropic Electrical Conductivity In A Hybrid Planar Inverse Problem, Athanasios Dimitriadis

Graduate Studies Theses and Dissertations 2026

Some single-physics medical imaging methods fail to reliably discriminate benign from malignant biological tissue. In partial response, a new class of inverse problems employ multi-physics phenomena, coupling methods of high resolution with methods of high contrast. In this thesis we are concerned with one such problem in which an anisotropic electrical conductivity is to be recovered from some internal knowledge of the current density field generated by maintaining a fixed boundary voltage. This internal data is obtained by the method of Current Density Impedance Imaging (CDII), which combines Maxwell's equations with Magnetic Resonance Imaging (MRI) measurements. The anisotropy class is …


Code-Switching, Identity-Shifting, And Identity Distress Among Black Undergraduate Women Attending Predominantly White Institutions, Erin Smith Jan 2026

Code-Switching, Identity-Shifting, And Identity Distress Among Black Undergraduate Women Attending Predominantly White Institutions, Erin Smith

Graduate Studies Theses and Dissertations 2026

Code-switching (altering language or speech) and identity-shifting (modifying appearance or behavior) are adaptive strategies often used by individuals from marginalized groups to navigate environments shaped by dominant cultural norms. Although these behaviors are commonly discussed in qualitative literature, relatively few quantitative studies have examined their psychological correlates among Black undergraduate women attending predominantly White institutions (PWIs). These behaviors may function as coping strategies in response to racialized and gendered expectations, yet the psychological implications of these strategies remain understudied. The present study examined the relationships among identity distress, code-switching, identity-shifting, and gendered racial identity centrality within a diverse sample of …


Toward Urban-Scale Liquefaction Hazard Analysis: Evaluation And Optimization Of Cpt-Based Lateral Displacement Assessment, Varun M. Singh Jan 2026

Toward Urban-Scale Liquefaction Hazard Analysis: Evaluation And Optimization Of Cpt-Based Lateral Displacement Assessment, Varun M. Singh

Graduate Studies Theses and Dissertations 2026

Liquefaction-induced lateral spreading is a major type of earthquake-induced ground failure hazard and poses a significant threat to infrastructure systems. While semi-empirical methods, such as Lateral Displacement Index (LDI), have been developed to estimate lateral spreading displacement (LSD), their efficacy for regional-scale liquefaction hazard assessment remains unknown. This study evaluates and improves the LDI method for urban-scale seismic hazard assessments using a comprehensive dataset consisting of 1,713 Cone Penetration Test (CPT) case histories from the 2011 Christchurch, New Zealand earthquake, and high-resolution topographic data. Comparing the predicted LSDs and ground-truth observations from both field investigations and remote-sensing surveys reveals that …


The Reliability, Validity, And Sensitivity Of Physical Working Capacity At The Pain Intensity Threshold, Danielle A. Sterner Jan 2026

The Reliability, Validity, And Sensitivity Of Physical Working Capacity At The Pain Intensity Threshold, Danielle A. Sterner

Graduate Studies Theses and Dissertations 2026

The purpose of this dissertation was to evaluate the reliability, validity, and responsiveness to training intervention of a pain-anchored capacity threshold, the Physical Working Capacity at the Pain Intensity Threshold (PWCPIT), as a practical submaximal marker of endurance-related exercise tolerance. Study one examined the test-retest reliability of pain-based, perceptual, and physiological physical working capacity measures in recreationally active men using a standardized multi-bout cycling protocol, with pain intensity responses demonstrating strong reproducibility and low measurement error, supporting the stability of pain-anchored thresholds when standardized procedures are applied. Study two evaluated the validity of PWCPIT by examining pain …


Thermomechanical Modeling Of Transpiration Surfaces For Hypersonic Propulsion, Spencer D. Smith Jan 2026

Thermomechanical Modeling Of Transpiration Surfaces For Hypersonic Propulsion, Spencer D. Smith

Graduate Studies Theses and Dissertations 2026

Hypersonic flight vehicles are a promising form of high speed passenger transport and efficient space access architectures. However, they are fundamentally a thermally limited technology. High heat fluxes exceeding 10 MW/m2 and gas temperatures between 3000-4000K can be found both within the engine, and on the outer surface. Current conventional engineering materials are non-viable at these conditions. In order to make these materials viable, active cooling strategies could be utilized. One particularly promising type is transpiration cooling, where a coolant is diffused through a porous surface. Although researched heavily in the 1960s, adoption is still minimal. Part of the reason …


Abig4l: A Semantic Reasoning Engine For Verilog Via Abstract Interpretation, Alicia Thoney Jan 2026

Abig4l: A Semantic Reasoning Engine For Verilog Via Abstract Interpretation, Alicia Thoney

Graduate Studies Theses and Dissertations 2026

Modern Electronic Design Automation (EDA) flows treat structural and semantic reasoning as separate concerns. Synthesis structurally optimizes RTL, while dedicated verification teams validate functional behavior through testbenches and formal methods. This organizational divide means designers have no automatic, sound way to understand what their RTL does at the moment they are writing it. This thesis introduces AbIG4L (Abstract Interpretation of Generic 4-valued Logic), a static analysis framework that bridges this gap by delivering sound semantic reasoning automatically, directly within the hardware design loop.

The framework operates on a language-agnostic intermediate representation to compute sound over-approximations of hardware behavior across 0, …


Oblique Detonation Waves In Internal Axisymmetric Converging Flow, Zachary P. White Jan 2026

Oblique Detonation Waves In Internal Axisymmetric Converging Flow, Zachary P. White

Graduate Studies Theses and Dissertations 2026

Detonative combustion offers significant thermodynamic advantages for high‑speed propulsion, motivating the development of detonation‑based combustors for hypersonic flight. Among these, oblique detonation wave (ODW) engines require extremely high combustor velocities to achieve steady wave stabilization. While most prior experimental and numerical studies have focused on planar two‑dimensional geometries, axisymmetric combustors offer practical benefits for hypersonic vehicle integration and may influence achievable pressure gain. However, the effects of inward‑turning axisymmetric compression on ODW formation and performance remain largely unexplored. This work presents an experimentally stabilized ODW formed on an internal axisymmetric converging ramp. Experiments were conducted in a high‑enthalpy blowdown wind …


Cfd Analysis Of A Full Heat Exchanger Between Ammonia And Supercritical Co2 In Aviation Application, Mairah Ahmed Jan 2026

Cfd Analysis Of A Full Heat Exchanger Between Ammonia And Supercritical Co2 In Aviation Application, Mairah Ahmed

Graduate Studies Theses and Dissertations 2026

The aviation industry’s transition toward lower-carbon propulsion systems has accelerated interest in alternative fuels, including ammonia–hydrogen fuel blends. In this work, a supercritical CO2 Brayton cycle is integrated with the exhaust stream of a turbofan engine to recover waste heat and utilize it for ammonia preheating and cracking. The recovered thermal energy raises the ammonia temperature to the level required for catalytic decomposition, enabling onboard hydrogen production. The proposed architecture combines ammonia cracking with a high-bypass, two-shaft turbofan engine representative of the propulsion system employed on the Boeing 737 MAX 8. This approach addresses the challenges associated with onboard hydrogen …


Charge Transport Modeling Of Multifunctional Molecular Transistors, Romena Akter Jan 2026

Charge Transport Modeling Of Multifunctional Molecular Transistors, Romena Akter

Graduate Studies Theses and Dissertations 2026

Distinguishing between the current–voltage characteristic curves associated with different transport mechanisms in a molecular electronic device and an artifact arising from device-level disorder is a central challenge in the study of molecular electronics. Characterizing these mechanisms and connecting them qualitatively to molecular-level orbital alignment, electrode coupling, voltage division, energetic disorder, and reorganization energy requires not only experimental data but also a rigorous theoretical framework for extracting physically meaningful parameters from measured transfer characteristics. This dissertation addresses this challenge in Chapters 2, 3, and 4 by developing and applying four complementary transport models —Simmons tunneling, single-level Landauer, Marcus hopping, and McConnell …


Robust Deep Learning One-Class Classification, Shahd Alnofaie Jan 2026

Robust Deep Learning One-Class Classification, Shahd Alnofaie

Graduate Studies Theses and Dissertations 2026

One-Class Classification (OCC) focuses on learning the characteristics of normal data and identifying observations that deviate from this learned pattern as anomalies. It is commonly used in applications such as medical diagnosis, cybersecurity, industrial monitoring, and fraud detection, where abnormal examples are often rare or unavailable during training. Classical approaches such as SVDD and LS-SVDD describe normal data using a hypersphere. While effective in some settings, these methods rely on shallow representations and can be sensitive to noise and contaminated observations. To address these limitations, this dissertation introduces a Deep LS-SVDD framework that combines hypersphere-based data description with deep neural …


Making Unsafe Sequences Unexecutable: Formal Protocol Enforcement For Cyber-Physical Systems, Arthur Amorim Jan 2026

Making Unsafe Sequences Unexecutable: Formal Protocol Enforcement For Cyber-Physical Systems, Arthur Amorim

Graduate Studies Theses and Dissertations 2026

Cyber-physical systems execute physical actions in response to software commands, making their communication protocols a primary attack surface. A stealthy attack is a sequence of individually valid messages that violates a required ordering, driving the system into an unsafe state without malware or protocol violation. Existing defenses examine messages or physical state in isolation, not protocol level sequences, and cannot prevent them. Preventing them requires enforcement that makes unsafe sequences unexecutable at the communication boundary.

Formal methods offer a principled path to enforcement, but no tool spans specification to safe deployed hardware. Model checking automates proofs but has no certified …


Numerical Investigation Of Reacting Flow In Pmma-Fueled Solid Fuel Scramjet Combustors Under Experimental Test Conditions, Hunter Bassett Jan 2026

Numerical Investigation Of Reacting Flow In Pmma-Fueled Solid Fuel Scramjet Combustors Under Experimental Test Conditions, Hunter Bassett

Graduate Studies Theses and Dissertations 2026

A simplified steady RANS-based numerical study of reacting flow in solid-fuel scramjet combustors is presented to evaluate the ability of commercial CFD frameworks to reproduce key features observed in experimental test sections. The work focuses on solid PMMA fuel in two supersonic combustor configurations: a cavity-assisted flameholding combustor and a variable-angle diverging combustor. The cavity combustor is analyzed as a baseline case and results are compared directly with experimental data. Three combustor geometry states corresponding to ignition, early-burning, and steady-burning conditions are investigated. Meshes are assessed through a systematic grid refinement method to establish grid independence. A novel variable-angle diverging …


Sensory And Emotional Impacts On Modern Consumer Experiences, Winter E. Bland Jan 2026

Sensory And Emotional Impacts On Modern Consumer Experiences, Winter E. Bland

Graduate Studies Theses and Dissertations 2026

This dissertation comprises two essays examining how environmental and psychological stimuli shape consumer experience, attitudes, and cognition. The first essay investigates the joint influence of scent temperature (warm versus cool) and scent arousal (stimulating versus relaxing) on experiential attitudes and cognitive performance in digitally mediated consumption environments. Across multiple lab experiments with biometric validation, findings reveal that these two scent dimensions interact to shape downstream outcomes. Warm, low-arousal scents (e.g., vanilla) enhance consumers' experiential evaluations of digital interactions but do not improve task performance, whereas cool, high-arousal scents (e.g., peppermint) boost cognitive efficiency and accuracy but do not elevate experiential …


An Examination Of The Impact Of School Context And Socioeconomic Status On Agency And Creative Productivity In Gifted High School Students, Elizabeth Bronson Jan 2026

An Examination Of The Impact Of School Context And Socioeconomic Status On Agency And Creative Productivity In Gifted High School Students, Elizabeth Bronson

Graduate Studies Theses and Dissertations 2026

This explanatory sequential mixed methods study investigated gifted high school students’ perception of the agency afforded them within school settings, and the relationship between these perceptions and their creative productivity. A sample of 140 students was drawn from a population of 966 identified gifted high school students. These students were contacted via their parents and asked to complete the Agentic Engagement Scale (AES) questionnaire which provided gifted high school students’ perceptions of the agency afforded at school. No significant differences in perceived agency were found across demographic variables, including socioeconomic status and school type. Of the respondents, 10 students were …


A Systematic Review And Characterization Of Privacy Noncompliance In Real-World Applications, Alexander E. Charkiewicz Jan 2026

A Systematic Review And Characterization Of Privacy Noncompliance In Real-World Applications, Alexander E. Charkiewicz

Graduate Studies Theses and Dissertations 2026

Software applications increasingly rely on user data to provide their functionality, but improper handling of such data can lead to serious privacy noncompliance with applicable regulations and policies. A prominent example is the Facebook–Cambridge Analytica scandal, in which a third-party application collected the personal data of approximately 87 million Facebook users without users' consent. Despite growing attention to privacy compliance, two key challenges hinder the systematic understanding and analysis of privacy noncompliance. First, unlike security vulnerabilities, which have been systematically categorized through taxonomies such as the Common Weakness Enumeration (CWE), privacy noncompliance lacks a technical taxonomy describing how it manifests …


Design, Fabrication Modeling, And Optical Metrology Of Mwir Silicon Metalenses, Weiyu Chen Jan 2026

Design, Fabrication Modeling, And Optical Metrology Of Mwir Silicon Metalenses, Weiyu Chen

Graduate Studies Theses and Dissertations 2026

Mid-wave infrared (MWIR) optical systems require compact, broadband, manufacturable components whose performance can be predicted and measured reliably. Silicon metalenses are attractive because silicon combines high refractive index, MWIR transparency, and semiconductor-compatible fabrication. This dissertation develops a scale-bridging design–fabrication-modeling–metrology framework for MWIR silicon metalenses.

A shared full-aperture framework connects meta-atom libraries, physical layout generation, angular-spectrum propagation, point-spread-function calculation, and focal-plane energy metrics. Building on this foundation, the Dispersive Sweatt Model (DSM) incorporates meta-atom dispersion into conventional ray-tracing software, enabling broadband co-optimization of metasurfaces and refractive elements. A process-aware design framework then incorporates scanning electron microscopy (SEM)-measured height–radius relationships produced by …


An Empirical Comparison Of K-Nearest-Neighbors And Logistic Regression Classification Models, Jackson Cushing Jan 2026

An Empirical Comparison Of K-Nearest-Neighbors And Logistic Regression Classification Models, Jackson Cushing

Graduate Studies Theses and Dissertations 2026

This thesis presents an empirical comparison of two classification methods: Logistic Regression and K Nearest Neighbors (KNN). The primary objective of this research is to evaluate the strengths and limitations of each method when applied to real-world datasets. Several publicly available datasets on diabetes, breast cancer, heart attack risk, and cardiovascular disease, were analyzed. For each dataset, K Nearest Neighbors models were implemented in the same way logistic regression had already been applied. The results demonstrate that while logistic regression offers interpretable parameter estimates and performs well when the underlying predictor and outcome relationship is approximately linear, however KNN can …


Non-Gaussian Phenomena In Light Scattering And Applications, Shubham Atul Dawda Jan 2026

Non-Gaussian Phenomena In Light Scattering And Applications, Shubham Atul Dawda

Graduate Studies Theses and Dissertations 2026

Physical reality is rarely deterministic; which, when probed by electromagnetic fields that also fluctuate, leads to observables that are most efficiently modelled as statistical processes. At equilibrium, this is usually achieved by invoking the Gaussian statistics of underlying physical processes, however, in practice, one often encounters out-of-equilibrium conditions where Gaussian descriptions may not suffice. Such situations are plentiful in nature– from biology to astronomy. This dissertation addresses several non-Gaussian phenomena associated with light scattering, and includes specific models’ derivations, experimental techniques developments, and demonstrations of potential applications. The systematic presentation will consider circumstances that infringe upon specific assumptions of the …


Exploring The Experiences Of Late Age-On-Arrival Multilingual Learners In Postsecondary Education, Robyn D. Ecklund Jan 2026

Exploring The Experiences Of Late Age-On-Arrival Multilingual Learners In Postsecondary Education, Robyn D. Ecklund

Graduate Studies Theses and Dissertations 2026

Multilingual learners (MLs) are the fastest growing population in the United States public school system (Biondi et al., 2024; Kanno & Cromley, 2013; Perez & Morrison, 2016; Varghese & Fuentes, 2020). Within this population of students, there is a subset of students that arrive in the United States during secondary school. These “late age-on-arrival” students face significant linguistic, cultural and social challenges in their pursuit of postsecondary success after high school (Kanno, 2021; Kanno & Cromley, 2013; Perez & Morrison, 2016). This interpretative phenomenological analysis sought to answer the research question: what are the lived experiences of late age-on-arrival MLs …


Investigating The Impact Of School Leaders’ Leadership Style And Teachers’ Intrinsic Motivation For Improved Science Instruction In Elementary Schools, Leila M. Greene Jan 2026

Investigating The Impact Of School Leaders’ Leadership Style And Teachers’ Intrinsic Motivation For Improved Science Instruction In Elementary Schools, Leila M. Greene

Graduate Studies Theses and Dissertations 2026

A report by the National Academies of Sciences, Engineering, and Medicine, determined that 69% of U.S. elementary teachers are not prepared to teach science, especially in the areas of earth/space and physical sciences. As a result, some elementary teachers avoid teaching science. School administrators play a key role in providing a supportive environment to inspire and motivate elementary science teachers. For this reason, the study utilized the Self-Determination Theory (SDT), to examine three types of school leadership styles (Transformational, Transactional, and Laissez-Faire) and how they impact the intrinsic motivation for elementary science teachers in three areas including autonomy, competency, and …


Deciphering Ultrafast Photoinduced And Photocatalytic Reaction Dynamics On Oxide Surfaces: Direct Detection Of Radical Intermediates, Fragment Trapping, And Carbon–Carbon, Carbon–Oxygen, And Carbon–Hydrogen Bond Formation Pathways, Aakash Gupta Jan 2026

Deciphering Ultrafast Photoinduced And Photocatalytic Reaction Dynamics On Oxide Surfaces: Direct Detection Of Radical Intermediates, Fragment Trapping, And Carbon–Carbon, Carbon–Oxygen, And Carbon–Hydrogen Bond Formation Pathways, Aakash Gupta

Graduate Studies Theses and Dissertations 2026

Understanding photoinduced reactions at solid interfaces is essential for advancing heterogeneous photocatalysis, surface photochemistry, and energy conversion technologies. This dissertation investigates the ultrafast dynamics of reactive intermediates, fragment trapping, and radical-mediated bond formation on oxide surfaces using time-of-flight mass spectrometry in conjunction with femtosecond pump-probe spectroscopy. Various experimental findings are validated through collaborations via density functional theory (DFT). By combining temporal, mass, and energy-resolved measurements, this work provides molecular-level insight into the elementary processes governing light-driven surface reactions. The photodissociation dynamics of CH3I adsorbed on TiO2(110), TiO2(100), and amorphous silicon oxide surfaces are examined …