Physical Sciences and Mathematics Commons^™

Insight Into The Binding Of Argon To Cyclic Water Clusters From Symmetry-Adapted Perturbation Theory, Carly A. Rock, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

This work systematically examines the interactions between a single argon atom and the edges and faces of cyclic H (Formula presented.) O clusters containing three–five water molecules (Ar(H (Formula presented.) O) (Formula presented.)). Full geometry optimizations and subsequent harmonic vibrational frequency computations were performed using MP2 with a triple- (Formula presented.) correlation consistent basis set augmented with diffuse functions on the heavy atoms (cc-pVTZ for H and aug-cc-pVTZ for O and Ar; denoted as haTZ). Optimized structures and harmonic vibrational frequencies were also obtained with the two-body–many-body (2b:Mb) and three-body–many-body (3b:Mb) techniques; here, high-level CCSD(T) computations capture up through the …

Environment And Sustainability: December 2023, Environment And Sustainability, Office Of The President

Environment and Sustainability Archives

• AKU’s Honourable Mention at the 2023 IHF Awards

• 7% energy savings at Stadium Road

• FMIC’s new solar water heater

• 2 Electric Shuttles for campus commuting

• AKU at COP28

• And much more…

Radiation Exposure Calibration Of The Al2o3:C With Radium-226 And Cesium-137 Using The Osl Method, Selma Tepeli Aydin

All Theses

Optically stimulated luminescence (OSL) dosimetry was utilized to calibrate Al₂O₃:C powder dosimeters, available commercially as the nanoDot® from Landauer Inc., and compare the dosimeter response to radium-226 (²²⁶Ra) and cesium-137 (¹³⁷Cs). The signal from the OSL was quantified using a microSTARii^® OSL reader also produced by Landauer Inc. Dose-response curves were developed for ²²⁶Ra and ¹³⁷Cs experiments (5 dosimeters each) at thirteen absorbed doses. Individual dosimeter response was tracked by serial number. Linear regression analysis was performed to determine if there were significant differences between the intercepts of the …

Les Taux De Rupture De Conduites D’Eau Principales Aux États-Unis Et Au Canada : Une Étude Complète, Steven L. Barfuss

Reports

Détérioration des infrastructures

Les municipalités et les personnes qu’elles servent dépendent des réseaux de conduites qui leur fournissent de l’eau potable de bonne qualité. Ces conduites sont souterraines, invisibles et souvent négligées.

Les résultats de l’évaluation globale de l’état des infrastructures hydrauliques ne sont pas bons. Prenons les États-Unis comme exemple :

· En 2009, l’American Society of Civil Engineers (ASCE) a publié un rapport sur les États-Unis et a attribué un D- aux infrastructures d’eau potable.

· En 2017, cette note est passée à D.

· En 2021, elle affiche une hausse à C-, ce qui est mieux, mais …

Intercomparison Of Planetary Boundary Layer Over El Paso-Juarez Region Using Vaisala Ceilometers, Vianey Arvilla

Open Access Theses & Dissertations

Vaisala ceilometers (models CL 31 and Cl 51) were used to monitor and study the planetary boundary layer (PBL). There were four ceilometer stations that we connected to create the Paso del Norte ceilometer network. These stations are located at: UTEP, Socorro, Ivanhoe, and Juarez. This network has been automatized and its hourly averaged mean boundary layer height data is being downloaded into a computer accessible to TCEQ (Texas Commission on Environmental Quality) and to the public. In this study, data from each ceilometer was used to produce scatter plots. These scatter plots were analyzed to obtain the PBL heights …

Towards A Model Of The Mapping Between English And Spanish Prosody, Jonathan Avila

Open Access Theses & Dissertations

Current speech-to-speech translation systems face challenges in effectively translating the nuances of prosody, which plays a pivotal role in conveying speaker intent and stance in dialog. This limitation restricts cross-lingual communication, especially in situations demanding deeper interpersonal understanding. To address this, this research delves into the relationships between prosody and its pragmatic functions, in English and Spanish. First, I discuss a data collection protocol in which bilingual speakers re-enact utterances from an earlier conversation in their other language, then describe an English-Spanish corpus, consisting of 3816 matched utterance pairs. Second, I describe a prosodic dissimilarity metric based on Euclidean distance …

A Noninvasive Urine-Based Method For Kidney Cancer Early Detection, Kiana Holbrook

Open Access Theses & Dissertations

Based on the traditional serological uses to obtain diagnoses of cancer and biopsy techniques, common cancer detection could be not only invasive but expensive and some tests are also unreliable. Currently, urine is one of the most frequently used and collected specimens in the clinical diagnoses. While the areas of urinalysis and metabolomic profiling has received interest in the top clinical research, there are limited components to the validity, specificity, as well as sensitivity of endogenous urine substrates to detect early stages of cancers. Although there is research showcasing that urine is impacted by age, cancer type, geographical location, and …

Niobate Nanosheet Catalysts For Cationic Dye Intercalation And Solar-Driven Water Photolysis, Cassandra Idona Monárrez-Grendahl

Open Access Theses & Dissertations

With the goal of creating efficient visible light photocatalysts for water photolysis, in this work we are exploring the synthesis of new porous oxide materials derived from potassium triniobate (KNb3O8) and titanium niobium oxide (KTiNbO5), which are layered wide band gap semiconductors. Generating hydrogen via direct water photolysis holds promise as a way to lower the cost of hydrogen gas production so it can be used as a renewable and clean alternative fuel. My group has demonstrated that layered semiconductor materials have the potential to enable the synthesis of new types of photocatalyst composites with customizable characteristics. In this work, …

Bitcoin's Technical Foundation And Its Potential For A Decentralized And Environmentally Friendly Future, Iqtiar Md Siddique

Open Access Theses & Dissertations

This research examines a systematic analysis of Bitcoin, employing a Coefficient of Variation (CV) approach to gauge its degree of decentralization. Bitcoin, an innovative decentralized digital currency, has received much attention for its potential to revolutionize traditional financial systems. This study employs the Coefficient of Variation (CV) to acquire insights into the wealth distribution and concentration among Bitcoin users. This research demonstrates how decentralized the network of Bitcoin is. The methodology uses real data on Bitcoin addresses and their holdings to compute the Coefficient of Variation (CV). This approach provides valuable insights into the ongoing discourse surrounding Bitcoin's decentralization, offering …

Changes In Physico-Chemical Properties Of A Sandy Loam Soil Depending On The Particle Size Of Hazelnut Shell-Derived Biochar, Damla Bender Özenç, Ceyhan Tarakçioğlu, Funda Irmak Yilmaz, Selahattin AygüN

The Philippine Agricultural Scientist

This study evaluated the effects of hazelnut shell-derived biochar particle sizes on the soil’s physical and chemical properties, and on various nutrient contents present in the sandy loamy soils. For this purpose, an incubation experiment in the plastic high tunnel has been performed under sixteen treatments (control-only soil), and at four incubation times (30, 60, 90, and 120 d), by using three different biochar sizes (≤ 1, 1 - 2, and 2 - 4 mm). The addition of 1 - 2 and 2 - 4 mm biochar during the incubation time decreased the bulk density in the soil by 26%. …

The Effect Of Amf-Cacao Association On Varying Physicochemical, Nutrient, And Biological Soil Parameters In An Agroforest System, Diana P. Paguntalan, Nelly S. Aggangan, Inocencio E. Buot Jr.

The Philippine Agricultural Scientist

The increasing interest in sustainable methods in agroforestry directs the attention of many to arbuscular mycorrhizal fungi (AMF) for their role in maintaining or improving overall plant health and nutrition of many plants including cacao (Theobroma cacao L.) trees. The effects of different treatments of AMF and other soil amendments applied singly or in combination on physicochemical properties, nutrient levels, spore count, and rhizosphere microbial counts, were investigated and compared across different sampling periods of varying climatological conditions in an agroforest system. Results showed that there was a significant effect on the N content using the different treatments. The …

Numerical Quantification Of Surface Runoff And Soil Erosion Using Pcraster, Victorino A. Bato

The Philippine Agricultural Scientist

Surface runoff and soil erosion of the Upper Lagawe River Sub-watershed, Ifugao Province, Philippines were quantified using Geographic Information Systems (GIS)-based numerical simulation. PCRaster software was used as a framework for the model. Manning’s and Rose, and Freebairn’s Equations were utilized to compute surface runoff velocity and sediment mass. Analysis and comparison of the measured and predicted streamflow yielded a mean Nash and Sutcliffe Efficiency Index of 0.70, a mean percent bias of -8.38%, and a mean root mean square error (RMSE) of 0.16. Based on the model, super typhoon Lando (international name: Koppu) generated an estimated surface runoff volume …

The Comprehensive Archive Of Substellar And Planetary Accretion Rates, S. K. Betti, K. B. Follette, K. Ward-Duong, A. E. Peck, Y. Aoyama, J. Bary, B. Dacus, S. Edwards, G. D. Marleau, K. Mohamed, J. Palmo, C. Plunkett, C. Robinson, H. Wang

Astronomy: Faculty Publications

Accretion rates ( M ̇ ) of young stars show a strong correlation with object mass (M); however, extension of the M ̇ - M relation into the substellar regime is less certain. Here, we present the Comprehensive Archive of Substellar and Planetary Accretion Rates (CASPAR), the largest compilation to date of substellar accretion diagnostics. CASPAR includes: 658 stars, 130 brown dwarfs, and 10 bound planetary mass companions. In this work, we investigate the contribution of methodological systematics to scatter in the M ̇ - M relation and compare brown dwarfs to stars. In our analysis, we rederive all quantities …

First Vlti/Gravity Observations Of Hip 65426 B: Evidence For A Low Or Moderate Orbital Eccentricity, Sarah Blunt, W. O. Balmer, J. J. Wang, S. Lacour, S. Petrus, G. Bourdarot, J. Kammerer, N. Pourré, E. Rickman, J. Shangguan, T. Winterhalder, R. Abuter, A. Amorim, R. Asensio-Torres, M. Benisty, J. P. Berger, H. Beust, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, G. Chauvin, A. Chavez, E. Choquet, V. Christiaens, Y. Clénet, Et Al, Kimberly Ward-Duong

Astronomy: Faculty Publications

Giant exoplanets have been directly imaged over orders of magnitude of orbital separations, prompting theoretical and observational investigations of their formation pathways. In this paper, we present new VLTI/GRAVITY astrometric data of HIP 65426 b, a cold, giant exoplanet which is a particular challenge for most formation theories at a projected separation of 92 au from its primary. Leveraging GRAVITY’s astrometric precision, we present an updated eccentricity posterior that disfavors large eccentricities. The eccentricity posterior is still prior dependent, and we extensively interpret and discuss the limits of the posterior constraints presented here. We also perform updated spectral comparisons with …

Many-Body Quantum Chaos In Stroboscopically-Driven Cold Atoms, Ceren B. Dağ, Simeon I. Mistakidis, Amos Chan, H. R. Sadeghpour

Physics Faculty Research & Creative Works

In Quantum Chaotic Systems, The Spectral Form Factor (SFF), Defined As The Fourier Transform Of Two-Level Spectral Correlation Function, Is Known To Follow Random Matrix Theory (RMT), Namely A 'ramp' Followed By A 'plateau' In Late Times. Recently, A Generic Early-Time Deviation From RMT, So-Called The 'bump', Was Shown To Exist In Random Quantum Circuits As Toy Models For Many-Body Quantum Systems. We Demonstrate The Existence Of 'bump-Ramp-Plateau' Behavior In The SFF For A Number Of Paradigmatic And Stroboscopically-Driven 1D Cold-Atom Models: Spinless And Spin-1/2 Bose-Hubbard Models, And Nonintegrable Spin-1 Condensate With Contact Or Dipolar Interactions. We Find That The …

Co2 Storage Capacity And Injectivity Of Stacked Carbonates Of The Pennsylvanian And Permian In Western Nebraska, Lateef Lawal

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Geological carbon storage (GCS) is a critical aspect of carbon capture and storage (CCS) in which captured CO₂ from power plants and industrial processes is injected and stored securely underground. Potential subsurface rock formations include saline aquifers, depleted oil and gas reservoirs, unmineable coal seams and volcanic rocks. GCS technology has been proven in the United States and many other parts of the world as a net-zero carbon emission strategy to mitigate the current climate crisis of our planet. Unlike other states such as Wyoming, GCS projects are still in the early phases in Nebraska. The goal of this …

Stream Restoration Effectiveness In Mullins Creek In Fayetteville, Arkansas, Amadeo Scott

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Lotic waterways are vital for habitat, food, water, and flood protection, but urbanization poses a major threat to their integrity. Runoff from urban surfaces leads to pollution, flashiness, loss of biodiversity, and other symptoms, also known as Urban Stream Syndrome (USS). To combat USS, streams can be restored, but most restorations are not monitored so their long-term effectiveness is unknown. This study quantitatively evaluated a decade-old stream restoration in Fayetteville, Arkansas, to assess its effectiveness in combating USS and achieving set restoration goals, and to gain insights for future restoration projects. Restoration goals included decreasing erosion and sedimentation, increasing pool …

Security Analysis Of Holystone Drones: Examining Attack Vectors And Data Extraction Techniques, Sandesh Ambadas More

Theses and Dissertations

In recent years, the surge in popularity of small-scale Unmanned Aerial Vehicles (UAVs), especially Holy Stone models, has raised significant security concerns. This study examines specific Holy Stone drone models, including the HS 175D, HS 430, HS 360S, and HS720, focusing on sub-250g drones exempt from FAA registration and those requiring registration and Remote ID. Despite advancements in drone technology, our research reveals persistent vulnerabilities that could be exploited by malicious actors for illicit purposes, posing a substantial security risk. Our comprehensive analysis involved simulated attacks in identifying and exploiting these vulnerabilities, leading to the successful acquisition of flight logs, …

Anxiety In International Graduate Students With U.S. Education, Aeshah Zarraa

Theses and Dissertations

Anxiety in international graduate students is a significant concern for most students planning to move out of their home country to pursue higher education in the United States. The primary purpose of this research is to identify the prime causes of anxiety triggers in the targetted Graduate students, thereby determining a step-wise methodology development to address the causes. The study initially identified a set of graduate students who were voluntarily willing to collaborate and address their concerns anonymously to identify the significant issues faced by current students and alumni of the Florida Institute of Technology, Melbourne, Florida. Several questions were …

Energy Extraction, Or Lack Thereof, Nishanth Gudapati

Mathematics

The problem of stability of rotating black holes is the subject of a long standing research program since the 1960s and remains an unresolved problem in general relativity. A major obstacle in the black hole stability problem is that the energy of waves propagating through rotating black holes spacetimes is not necessarily positive-definite, due to the so called ergo-region. This is a serious complication that limits the efficacy of most mathematical techniques. In this expository article, we report that, despite the ergo-region, there exists a positive-definite total energy for axisymmetric Maxwell, gravitational and electrovacuum perturbations of Kerr and Kerr–Newman black …

Influence Of Pavement Conditions On Commercial Motor Vehicle Crashes, Stephen Arhin, Babin Manandhar, Adam Gatiba

Mineta Transportation Institute

Commercial motor vehicle (CMV) safety is a major concern in the United States, including the District of Columbia (DC), where CMVs make up 15% of traffic. This research uses a comprehensive approach, combining statistical analysis and machine learning techniques, to investigate the impact of road pavement conditions on CMV accidents. The study integrates traffic crash data from the Traffic Accident Reporting and Analysis Systems Version 2.0 (TARAS2) database with pavement condition data provided by the District Department of Transportation (DDOT). Data spanning from 2016 to 2020 was collected and analyzed, focusing on CMV routes in DC. The analysis employs binary …

Applications Of Diels-Alder Cycloadditions And Transition Metals As Catalysts To Recent Total Syntheses, Alexander H.C. Evans

Legacy Theses & Dissertations (2009 - 2024)

This thesis examines the recent advances in the applications of Diels-Alder cycloaddition reaction and Suzuki-Miyaura coupling to total syntheses of antibiotic and anti-cancer drugs. Attention is also given to intramolecular Diels-Alder cycloadditions and the use of Kinetic vs. Thermodynamic conditions. The results of the Diels-Alder cycloadditions that are discussed oftentimes result in high stereospecificity, regioselectivity, and stereoselectivity. The applications of Suzuki-Miyaura coupling and transition metal catalysts to total syntheses problems are also discussed along a similar narrative. Attention is given specifically to the use of several different gold catalysts as well as Grubb’s Catalyst. The use of the Diels-Alder cycloaddition …

Enhanced Market Timing: Long Short-Term Memory Neural Network For Optimal Entry And Exit In Stock Market, Jerome Chinua Hall

Legacy Theses & Dissertations (2009 - 2024)

This thesis investigates applying a Long Short-Term Memory (LSTM) Neural Network for forecasting optimal times to enter and exit the stock market. Given the inherent imbalance in the dataset, where most days are not opportune for market actions, and the challenge of predicting such infrequent occurrences, we will employ a five-day window before and after the identified optimal market entry or exit time. A prediction is considered correct if it is within this five-day interval. The model was trained on historical S&P 500 data, using features such as exponential and simple moving averages of the closing price, the ten-day percentage …

Solubility, Reactivity And Diffusion In Polymeric Bilayer Thin Films, Jacob Sitterly

Legacy Theses & Dissertations (2009 - 2024)

Microelectronics manufacturing of modern devices has required the use of polymer photoresists in several essential steps. The traditional limitation in device capability has been dependent on the minimum feature size attainable by the wavelength of light and materials used in photolithography. In this thesis the study of polymer thin films in single and bilayer stacks is described. Three scientific concepts are fundamental to this study: (1) the diffusion and (2) reaction of acid and small molecules that change polymer (3) solubility. In this thesis, two chemical systems are designed and used to study these three scientific concepts.

The Effects Of Aggregation Of Tetrafluoro(Trifluoromethyl-Λ6-Sulfanyl) Ethanes On The Secondary Structure Stabilization Of Melittin: A Molecular Dynamics Simulation Study, Samadrita Biswas

Legacy Theses & Dissertations (2009 - 2024)

Introduction of novel tetrafluoro(trifluoromethyl-λ6-sulfanyl) (CF3SF4) functional group has garnered substantial interest because of its increased hydrophobicity. This super fluorinated group attributed to increased lipophilicity, decreased heat of vaporization, and lowered dielectric constants. The highly electronegative nature of this group can profoundly influence the reactivity of compounds containing the CF3SF4 moiety. The hypervalency associated with this new group presents an exciting platform to explore the fundamental understanding of molecular interactions, reactivity patterns, and electronic behaviors. This dissertation investigates the molecular properties and behaviors of tetrafluoro(trifluoromethyl-λ6-sulfanyl) ethanes (CF3SF4-ethanes), with a specific emphasis on 2-tetrafluoro(trifluoromethyl)-λ6-sulfanylethan-1-ol (CF3SF4-ethanol) and 2-tetrafluoro(trifluoromethyl)-λ6-sulfanylethanamine (CF3SF4-ethanamine). Utilizing ab initio calculations …

An Investigation Into Past And Future Freezing Level Height And Equilibrium Line Altitude In The Tropical Andes Using Cmip6, Shelby Turner

Legacy Theses & Dissertations (2009 - 2024)

The freezing level height (FLH) in the tropical Andes has increased over the past several decades, as is evident with the receding of alpine glaciers in this region. The accuracy of Global Climate Models (GCMs)—specifically previous generations of the Coupled Model Intercomparison Project (CMIP)—in this region remains an issue, as the complex terrain and climate characteristics are difficult to simulate realistically. The changes seen in these tropical alpine glaciers in the past few decades are a clear indicator of the effects climate change is having in this tropical mountain region, making it important to better understand current and projected future …

Photosensitized Chemically Amplified Resist (Pscar) For Extreme Ultraviolet Lithography (Euvl), Israt Hossain

Legacy Theses & Dissertations (2009 - 2024)

As Deep Ultraviolet (DUV) Photolithography has hit the limit in further shrinking semiconductor devices' critical dimension (CD) down to below 10 nm, using Extreme Ultraviolet (EUV) 13.5 nm wavelength is under intense development. EUV has higher resolution (R) as a consequence of the shorter wavelength, but EUV sources have much lower light intensity than DUV light sources, leading to sensitivity challenges. While light source intensity and photoresist sensitivity (S) have a complementary relationship, and high intensity EUV light source development only progresses slowly, this paper discusses other novel approaches to improve photoresist sensitivity with low intensity EUV light. Photosensitization chemistry …

Characterizing And Understanding Orographic Precipitation Over The Mountains Of Extratropical South America, Yazmina Rojas Beltran

Legacy Theses & Dissertations (2009 - 2024)

Extratropical South-America (30-40°S) varies significantly in topography, including a coastal mountain range with elevation from 700-1300 m, a central valley, and the Andes, with elevation from 1000-2500 m on the western side of the continent. The topography of the area can disrupt frontal systems approaching from the Pacific Ocean, leading to enhanced orographic precipitation over the windward slope of the Andes and a sharp rain shadow, with less precipitation in the leeside. These phenomena are also observed over the coastal mountains of south-central Chile. The main goals of this study are to characterize and understand orographic precipitation and rain shadow …

Planar, Twisted, And Macrocyclic Polyarenes: Structures, Reduction Limits, And Reactivity, Matthew John Pennachio

Legacy Theses & Dissertations (2009 - 2024)

Molecular nanocarbons, which can be considered as fragments of fullerenes, carbon nanotubes, or graphene have invigorated the rapid development of carbon chemistry at the nanoscale in recent decades. Not only do molecular nanocarbons possess extraordinary chemical and physical properties, but they also exhibit such unique features as controllable and scalable molecular compositions, atomically uniform precision, and good stability. The advance of nanocarbon chemistry give rise to unique applications such as electron transfer, semiconductors, superconductors, and lithium-ion batteries. However, an in-depth understanding of controlled doping, charge transfer effects, and structure–property correlations has been limited in nanocarbon chemistry due to the lack …

Leveraging Generative Agents: Autonomous Ai With Simulated Personas For Interactive Simulacra And Collaborative Research, James Hutson, Jay Ratican

Faculty Scholarship

The advent of large language models (LLMs) and AI learning have fundamentally reshaped the research landscape, paving the way for novel problem-solving approaches. This paper introduces a unique framework that leverages the capabilities of autonomous AI agents with simulated personas to drive collaborative research in groundbreaking ways. Inspired by a recent study of autonomous agents mirroring human behavior, this concept encourages the use of a cadre of AI agents, each possessing specialized expertise for collective endeavors. By replicating human diversity in teamwork, this approach targets complex and hitherto unsolvable issues. The key to this strategy is persona and emotional simulation, …