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Articles 4351 - 4380 of 302419

Full-Text Articles in Physical Sciences and Mathematics

No "Butts" About It: The Heavy Metal Impact Of Cigarette Litter, Faith Huff, Connor Monson, Spencer Whittington Apr 2024

No "Butts" About It: The Heavy Metal Impact Of Cigarette Litter, Faith Huff, Connor Monson, Spencer Whittington

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Cigarettes are the most common litter globally. Following smoking, the filter is left with carcinogenic compounds, tar and metals. All of which are highly toxic for wildlife, affecting reproduction, behavior and mortality rate in animals. The heavy metals that are left within the filter also have potential to leach from the cigarettes and enter the groundwater system. As these heavy metals enter the system, it leads to adverse effects on the environment and can cause detrimental health effects in humans, such as cell damage, induced carcinogenic processes and loss of cellular functions. Much research that exists currently only focuses on …

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Potential Non-Carbonate Buffering In An Interdunal Wetland/Slack Along Lake Michigan, Faith Huff Apr 2024

Potential Non-Carbonate Buffering In An Interdunal Wetland/Slack Along Lake Michigan, Faith Huff

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Interdunal wetlands/slacks occur in Lake Michigan's coastal dunes where the wind scours the sand to the water table. Since May 2016 we have performed ecohydrological studies on the largest interdunal wetlands/slack, ~1.25 ha in size, lying within a deflated parabolic dune east of Lake Michigan at the Saugatuck Harbor Natural Area, Michigan. The slack’s hydrology is influenced by Lake Michigan-Huron, appearing and increasing in size and water depth with rising lake levels and decreasing in size to drying with low levels. Prior to 2014, the slack was completely dry and dominated by upland dune species due to low lake levels. …

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Β-Decay Strength Function Of 99,100 Y, Nathaniel Jobson, A. Spyrou Apr 2024

Β-Decay Strength Function Of 99,100 Y, Nathaniel Jobson, A. Spyrou

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

The rapid neutron capture process (r process) is responsible for the formation of numerous nuclei in the universe. To obtain better models for heavier nuclei that are part of the r process, the decay paths of 99,100Y were analyzed. This work was done using the Summing NaI(Tl) detector at the National Superconducting Cyclotron Laboratory. The Iβ(E) and the Beta Gamow-Teller function (BGT) were extracted from the measured Total Absorption Spectroscopy (TAS), Sum of Segments (SEG), and Multiplicity spectrum. The Iβ(E) and the Beta Gamow-Teller function (BGT) were extracted from the measured spectra and then compared to the Quasi Random Phase …

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Turbulence And Zonal-Flow Impact In The Madison Symmetric Torus In Quasi-Single Helicity, Nicholas J. Kaipainen, Y. L. De Jong, L. Helder, M. J. Pueschel, J. S. Sarff, P. W. Terry, P. D. Vanmeter Apr 2024

Turbulence And Zonal-Flow Impact In The Madison Symmetric Torus In Quasi-Single Helicity, Nicholas J. Kaipainen, Y. L. De Jong, L. Helder, M. J. Pueschel, J. S. Sarff, P. W. Terry, P. D. Vanmeter

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Reversed-Field Pinches (RFPs) operating in the Quasi-Single-Helicity (QSH) magnetic geometry exhibit significant improvements in confinement time as compared to standard discharges due to the efficient saturation of large-scale tearing modes. This modification to the magnetic geometry and profiles introduces new instabilities which drive transport. This work focuses on diagnosing the microinstabilities and microturbulence in a non-reversed Madison Symmetric Torus QSH experiment. Local gyrokinetic simulations are conducted with the GENE code to identify the dominant instabilities as ion-temperature-gradient (ITG) and density-gradient-driven trapped-electron-mode (TEM) at core and edge radial locations, respectively. It has been previously observed in the RFP (Williams PoP 2017) …

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Identity Development Among Pre-Health Students During The Covid-19 Pandemic, Anya Kapitula, Anna Tyshka Apr 2024

Identity Development Among Pre-Health Students During The Covid-19 Pandemic, Anya Kapitula, Anna Tyshka

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Many sociology studies have been published regarding the experiences and development of medical school students, but there is a gap in research observing undergraduate students on pre-health professions tracks. Specifically, studies have been published noting a significant decrease in the empathy of medical school students during their third year, but no research has been conducted to identify development patterns of these students during their undergraduate years. This study aims to identify groups of undergraduate students on pre-health professions tracks based on typologies formed from longitudinal survey responses, and also to identify any significant transitions between these groups over time. Because …

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The Synthesis And Electropolymerization Of Porphyrin-Substituted Ethylenedioxythiophene (Edot) Monomers, Benjamin D. Mcintyre, Joshua A. Hawkins, Kenneth L. Brown Apr 2024

The Synthesis And Electropolymerization Of Porphyrin-Substituted Ethylenedioxythiophene (Edot) Monomers, Benjamin D. Mcintyre, Joshua A. Hawkins, Kenneth L. Brown

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Two electroactive monomers were synthesized for use in forming redox-active films on electrodes. Such electroactive films are useful as redox mediating coatings in the functionalization of electrodes for sensor applications. Tetraphenylporphyrins were coupled to 3,4-ethylenedioxythiophene (EDOT) using different connector lengths and then metallated with iron to form monomers capable of electropolymerization. Hydroxymethyl EDOT was tosylated and then reacted with 4-hydroxybenzaldehyde in a Williamson ether synthesis to give an EDOT-functionalized aldehyde. This aldehyde was condensed with pyrrole under acidic conditions to form a novel EDOT-substituted porphyrin. The second porphyrin monomer was prepared similarly with a four carbon chain connector inserted between …

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The Breaking Of Carbon-Carbon Bonds In Alkyl Ketones, Jenna R. Mustapha, Jordan K. Montgomery, Karen M. Nimtz, Ainsley G. Vandenbrink Apr 2024

The Breaking Of Carbon-Carbon Bonds In Alkyl Ketones, Jenna R. Mustapha, Jordan K. Montgomery, Karen M. Nimtz, Ainsley G. Vandenbrink

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

The breaking of carbon-carbon bonds holds great promise for organic chemistry synthesis. This project specifically looks at using a rhodium catalyst to perform a decarbonylation. The focus is to observe the outcome of a variety of different alkyl groups attached to ketones as they undergo decarbonylation reactions. Depending on the alkyl ketone, the reaction can proceed via direct decarbonylation and/or beta-hydride elimination. The goal of this project includes controlling the selectivity of these reactions for the desired product and expanding the library of successful ketones containing alkyl groups used for the reactions.

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Temperature Sensitivity Of Nitrogen Mineralization In Peat From Bogs Across A Michigan Transect, Madison Smith, Hannah Sturgeon, Abigail Brewer, Gael Figueroa-Enriquez, Christopher Klaver Apr 2024

Temperature Sensitivity Of Nitrogen Mineralization In Peat From Bogs Across A Michigan Transect, Madison Smith, Hannah Sturgeon, Abigail Brewer, Gael Figueroa-Enriquez, Christopher Klaver

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

In this study, seven peat bogs across a latitudinal transect of Michigan were used to analyze inorganic nitrogen (nitrate and ammonium) release from peat to predict the impact that climate warming has on peatland nitrogen cycle. More nitrogen release is expected in samples kept at warmer temperatures (simulated climate warming) and also from samples from lower latitudes in the transect. 1-m peat core samples were taken at each site. 20 g of acid washed sand was added to upper chambers of microlysimeters (two-chambered filter towers). 50 g of peat was added onto the sand and was left to equilibrate for …

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Mechanochemical Formation Of Polyacrylamide Nanocomposites: Impact Of Nanoparticle Surface Chemistry And Substrate Functionalization, Bryn Couturier, Lauren Buckley, Connor Bovia Apr 2024

Mechanochemical Formation Of Polyacrylamide Nanocomposites: Impact Of Nanoparticle Surface Chemistry And Substrate Functionalization, Bryn Couturier, Lauren Buckley, Connor Bovia

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Osteoarthritis is a degenerative joint condition, with treatments currently limited to symptom management and invasive surgical procedures. This project investigates the fundamental mechanisms for a potential treatment route that would allow soft material nanocomposites to form within the joint through mechanochemical reactions. To gain fundamental insight into the different chemical pathways for this to occur, this work compares a top-down vs bottom-up approach. The top-down method focuses on the influence of applied oscillatory mechanical stresses on bulk hydrogel polymerization. Polyacrylamide (PAM) is used as a well-studied control system. PAM-nanocomposites were achieved through co-polymerization, with gold nanoparticles with different capping ligands …

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Development Of A Consistent Proton Induced Gamma Emission Liquid 19f Standard, Jordan Craft, Ryan Mccreedy, Naomi Whitfield, Loic Rutabana Apr 2024

Development Of A Consistent Proton Induced Gamma Emission Liquid 19f Standard, Jordan Craft, Ryan Mccreedy, Naomi Whitfield, Loic Rutabana

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

We developed a new technique to quantify PFAS (Fluorine) contamination in water using Hope College’s particle accelerator. To do this, we created an ~2000 PPM NaF in water standard and carefully controlled the experimental configuration. We are hoping that careful control of the experimental conditions will yield a consistent 19F gamma-ray count per Coulombs from Proton Induced Gamma-ray Emission (PIGE). 3.4MeV protons have enough energy to exit the particle accelerator, travel 27 mm in air, and penetrate into the liquid standard. As protons lose energy in the liquid, nuclear reactions such as (p, p’gamma) with the 19F and 23Na nuclei …

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Material Characterization For Industrial Processes Of Thin Titanium Nanotube Films, Nathaniel Jobson, Jacob Walther, Justin Rink, Wil Pinkerton Apr 2024

Material Characterization For Industrial Processes Of Thin Titanium Nanotube Films, Nathaniel Jobson, Jacob Walther, Justin Rink, Wil Pinkerton

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Material characterization is an important step in the experimental processes. This step ensures that the samples' processing yields the intended results. This work outlines the process taken to analyze and characterize a set of industrial thin films. Our characterization starts with an elemental baseline from scanning electron microscopy (SEM). The composition is verified by SimNRA (Simulation Nuclear Reaction Analysis) calculations fitting Rutherford Backscattering (RBS) data collected from a silicon surface barrier (particle) detector.

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Characterization And Testing Of Sipms For A Next-Generation Neutron Detector, Bishop Carl Apr 2024

Characterization And Testing Of Sipms For A Next-Generation Neutron Detector, Bishop Carl

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

MoNA-LISA is a position-sensitive neutron detector at the Facility for Rare Isotope Beams (FRIB) used to probe neutron-unbound states through invariant-mass spectroscopy. Position resolution of the neutron detector is a key factor in invariant mass measurements. A better neutron position would significantly improve the overall reconstructed decay energy resolution and would therefore lead to a better understanding of nuclei near and beyond the dripline. The MoNA collaboration is designing a next-generation neutron detector to improve the current MoNA-LISA resolution (~5cm). The new design will replace the PMTs for SiPM arrays as readout technology. The use of SiPMs (more compact) for …

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Expanding The Use Of Palladium-Catalyzed Beta-Aryl Elimination Reactions, Anna G. Tyshka, Tyler J. King, Lucas D. Day, Timothy R. Welsh Apr 2024

Expanding The Use Of Palladium-Catalyzed Beta-Aryl Elimination Reactions, Anna G. Tyshka, Tyler J. King, Lucas D. Day, Timothy R. Welsh

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Transition metal-catalyzed cross-coupling reactions involving organic boronic acids are ubiquitous throughout organic synthesis. Despite the popularity of these methods, some boronic acids, such as those with 2-heteroaryl, 2-fluoroaryl, and cyclopropyl substituents, are incompatible, as these species decompose via protodeboronation prior to their incorporation into the desired reaction. To circumvent the protodeboronation process, the organometallic intermediates typically generated via catalyst transmetallation with a boronic acid can instead be generated via β-carbon elimination Efforts will focus on solving the so-called "2-pyridyl problem" and broadening the scope of known coupling partners in a Suzuki-like reaction, then systematically expand to include other palladium- and …

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Artificial Sociality, Simone Natale, Iliana Depounti Apr 2024

Artificial Sociality, Simone Natale, Iliana Depounti

Human-Machine Communication

This article proposes the notion of Artificial Sociality to describe communicative AI technologies that create the impression of social behavior. Existing tools that activate Artificial Sociality include, among others, Large Language Models (LLMs) such as ChatGPT, voice assistants, virtual influencers, socialbots and companion chatbots such as Replika. The article highlights three key issues that are likely to shape present and future debates about these technologies, as well as design practices and regulation efforts: the modelling of human sociality that foregrounds it, the problem of deception and the issue of control from the part of the users. Ethical, social and cultural …

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The Black-To-White Hole Transition, Farshid Soltani Apr 2024

The Black-To-White Hole Transition, Farshid Soltani

Electronic Thesis and Dissertation Repository

Classically, an isolated black hole is a stable gravitational object. If however semiclassical effects are taken into account, an isolated black hole can be shown to slowly radiate its mass away in a process called evaporation. At the end of the evaporation process, when the size of the horizon becomes Planckian, the quantum nature of the gravitational field can no longer be neglected and the dynamics of the horizon is governed by quantum gravity. The main objective of this thesis is the systematic investigation of a tentative scenario for the “end of the life” of a black hole: the black-to-white …

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Optimal Control Of Coefficients For The Second Order Parabolic Free Boundary Problems, Ali Hagverdiyev Apr 2024

Optimal Control Of Coefficients For The Second Order Parabolic Free Boundary Problems, Ali Hagverdiyev

Mathematics Colloquium Series

In this talk I will discuss Inverse Stefan type free boundary problem for the second order parabolic equation arising for instance, in modeling of laser ablation of biomedical tissues, where the information on the coefficients, heat flux on the fixed boundary, and density of heat sources are missing and must be found along with the temperature and free boundary. New PDE constrained optimal control framework is employed, where the missing data and the free boundary are components of the control vector, and optimality criteria are based on the final moment measurement of the temperature and position of the free boundary. …

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H(Hydrogen)-Alpha Spectral Imaging Of Z>5 Quasars, Pratik Paudel, Mari Hirota, Hyunsung Jun Apr 2024

H(Hydrogen)-Alpha Spectral Imaging Of Z>5 Quasars, Pratik Paudel, Mari Hirota, Hyunsung Jun

Celebration of Research

We aim to measure the H-alpha line excess over the photometric continuum for distant quasi-stellar radio objects, or quasars. Supermassive black holes grow in mass through accretion of stars or gas nearby, often outshining the total stellar light of the galaxies they reside in, for quasars. On the other hand, the structure of these active galactic nuclei are hard to resolve, where we often rely on the relationship in between different light emission regions to better understand the geometry and emission mechanisms. In this work, we measure the H-alpha luminosity of 44 quasars at z>5 (light coming from less …

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Metabolic Characterization Of Porcine Hepatocytes, Sophie Swart, Ainslie Robinson, Daiki Jonouchi, Marcus Blankespoor, Kip Cullinan, Zachary Varpness, Ryan Schulze Apr 2024

Metabolic Characterization Of Porcine Hepatocytes, Sophie Swart, Ainslie Robinson, Daiki Jonouchi, Marcus Blankespoor, Kip Cullinan, Zachary Varpness, Ryan Schulze

Celebration of Research

No abstract provided.

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The Impact Of Blood Flow Restriction On Heart Rate And Muscle Activation, Janaya Battles, Rajat Singh, Daniel Swier Apr 2024

The Impact Of Blood Flow Restriction On Heart Rate And Muscle Activation, Janaya Battles, Rajat Singh, Daniel Swier

Celebration of Research

Blood Flow Restriction (BFR) is a rehabilitation technique used in physical therapy to improve muscle growth in patients. The technique involves using blood cuffs on the limbs to occlude blood flow within the muscles, thus limiting the buildup of muscle growth inhibitors. The current literature provides information regarding these aspects but is limited in providing information regarding the impact of BFR on neural muscular coordination. Therefore, the purpose of this study was to determine how various pressure levels of the BFR cuffs can impact the muscle activation of the restrained muscles and heart rate. Our results have shown that a …

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Phun With Phages: Discovering Novel Bacteriophages In The Soil, Julia Kutz, Ryan Dodds, Logan Dykstra, Taylor M. Rentschler, Emma Steinhardt, Megan Vangarven, Jacie Vanderwaal, Shayler Vangelder, Byron Noordewier, Sara S. Tolsma Apr 2024

Phun With Phages: Discovering Novel Bacteriophages In The Soil, Julia Kutz, Ryan Dodds, Logan Dykstra, Taylor M. Rentschler, Emma Steinhardt, Megan Vangarven, Jacie Vanderwaal, Shayler Vangelder, Byron Noordewier, Sara S. Tolsma

Celebration of Research

We used three bacterial hosts: Mycobacterium smegmatis, Microbacterium foliorum, and Gordonia terrae, to isolate novel bacteriophages from soil samples. We named these phages, created high titer lysates, and purified their DNA genomes. We have archived the high titer lysates at Northwestern College and the University of Pittsburgh. The genomes of three of our phages were sequences at the University of Pittsburgh and we will be sequencing the remaining genomes this summer. Additionally, we are planning to image our phages with transmission electron microscopy at the University of Iowa or Nebraska yet this semester.

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2024 April 11 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University Apr 2024

2024 April 11 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

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Context-Aware Affective Behavior Modeling And Analytics, Md Taufeeq Uddin Apr 2024

Context-Aware Affective Behavior Modeling And Analytics, Md Taufeeq Uddin

USF Tampa Graduate Theses and Dissertations

Affective computing (AC) is a sub-domain of AI that has the potential to assist people by assessing mental states and making appropriate recommendations to patients, loved ones, caregivers, and domain experts. Humans usually produce an enormous amount of data (such as face videos) every day. One of the major challenges for affective computer vision is to efficiently deal with high volumes of data to facilitate automated model development. To cope with this challenge, we developed computer vision algorithms that measure the expressivity of the human face from video data. More precisely, the developed algorithms can map complex affect information from …

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The Effectiveness Of Using Near-Peer Role Models And Mentoring: A Phenomenological Reflection On Stem For Success, Bruce G. Bukiet, Cristo Leon, James Lipuma Apr 2024

The Effectiveness Of Using Near-Peer Role Models And Mentoring: A Phenomenological Reflection On Stem For Success, Bruce G. Bukiet, Cristo Leon, James Lipuma

STEM for Success Resources

The proper study of communication from existing models opens the doors to scientific research that allows exploring language and coding as an integral part of effective communication to generate new models that include Trans-Disciplinary Collaboration. The authors analyze the communication factors to describe the application of Trans-Disciplinary Communication. This paper aims to define communication processes and their relationship with language, considering their impact on trans-disciplinary collaboration and innovation. After conducting a systematic literature review, the article explored the concepts of communication, functions, language, and Trans-Disciplinary Communication. This led to its application in the convergence research approach presented in the Collaborative …

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Protecting American Children: A Social-Ecological Analysis Of Pactp4, Julia Rossmiller Apr 2024

Protecting American Children: A Social-Ecological Analysis Of Pactp4, Julia Rossmiller

Student Works

The quantity of pesticides used annually in the United States exceeds one billion pounds every year, and the amount is only rising. The current law that governs the use of pesticides—The Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), permits the use of 72 known pesticides that have been proven harmful and are banned in other countries. Research links the usage of pesticides to the health of individuals, families, and whole communities within the environment. Moreover, dangerous pesticides have been shown to disproportionately affect children, agricultural workers, people of color, and low-income communities. Despite the mounting evidence that confirms the adverse …

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Machine Learning Techniques For Intermediate Mass Gap Lepton Partner Searches At The Large Hadron Collider, Bhaskar Dutta, Tathagata Ghosh, Alyssa Horne, Jason Kumar, Sean Palmer, Pearl Sandick, Marcus Snedeker, Patrick Stengel, Joel W. Walker Apr 2024

Machine Learning Techniques For Intermediate Mass Gap Lepton Partner Searches At The Large Hadron Collider, Bhaskar Dutta, Tathagata Ghosh, Alyssa Horne, Jason Kumar, Sean Palmer, Pearl Sandick, Marcus Snedeker, Patrick Stengel, Joel W. Walker

Michigan Tech Publications, Part 2

We consider machine learning techniques associated with the application of a boosted decision tree (BDT) to searches at the Large Hadron Collider (LHC) for pair-produced lepton partners which decay to leptons and invisible particles. This scenario can arise in the minimal supersymmetric Standard Model (MSSM), but can be realized in many other extensions of the Standard Model (SM). We focus on the case of intermediate mass splitting (∼30 GeV) between the dark matter (DM) and the scalar. For these mass splittings, the LHC has made little improvement over LEP due to large electroweak backgrounds. We find that the use of …

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Chemtrails: Deadly Skies Or Dangerous Misinformation?, Abigail Foust Apr 2024

Chemtrails: Deadly Skies Or Dangerous Misinformation?, Abigail Foust

Undergraduate Research Symposium

A common sight on a clear day is a thin strip of white across the otherwise blue sky: A contrail. Most people do not think anything of these contrails, and assume they have little to no impact on the world at large. Suppose for a moment, however, that they are not as harmless as some believe. Suppose these cloud trails are actually composed of dangerous chemicals, and are being used by sinister forces in a conspiracy to kill off the weak, mind-control the population, or simply dull our minds in preparation for a government takeover. As far-fetched as this may …

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Heat's Effect On Asphalt Binders Using Nmr, Kaitlin Miles Apr 2024

Heat's Effect On Asphalt Binders Using Nmr, Kaitlin Miles

Undergraduate Research Conference at Missouri S&T

Nuclear Magnetic Resonance (NMR) spectroscopy is a well-known analytical technique that uses the excitation of nuclear spins for solving chemical structures and conformations. Relaxometry is a special field of NMR spectroscopy where information is gained about interactions of 100 nuclear spins with their molecular surroundings. The deterioration of asphalt is a major infrastructure problem, and its rejuvenation back toward its original virgin state is an important field of research and development. The current asphalt industry relies on visual inspection on site and invasive or destructive physical methods to assess emerging asphalt failures. This study examines the chemical changes environmental factors …

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Amorphous Transparent Oxide P-Type Semiconductors, Joshua Santy Apr 2024

Amorphous Transparent Oxide P-Type Semiconductors, Joshua Santy

Undergraduate Research Conference at Missouri S&T

For decades, n-type transparent conducting oxides (TCOs) have been extensively studied and applied in various energy and optoelectronic devices. However, the search for high-performance p-type TCOs, crucial for transparent p-n junctions and next-generation microelectronics - remains uncertain. The most studied p-type TCOs (e.g ., Cu2O-based delafossite family) exhibit the carrier mobilities (<1 cm2Ns) that are much smaller than those in typical n-type TCOs (10-100 cm2Ns). In contrast to the Cu-based layered materials with a relatively flat Cu d10 valence band (resulting in the hole effective mass of 2.5me), Sn2+ in SnO has s2 electronic configuration giving rise to a significantly more dispersed valence band (the hole effective mass is 0.5me) and, hence, to higher hole mobility. Currently, the practical use of SnO is limited due to (i) stability issues of SnO associated with tin preference for valence 4 (as in SnO2, a well-known n-type TCO); (ii) small band gap ~0.7 eV; and (iii) anisotropic hole effective mass in the crystalline phase. Further search for p-type TCOs should involve amorphous phases of SnO-based multi-cation materials where metal composition helps stabilize Sn2+ and open the band gap, whereas the disordered structure is expected to result in uniform isotropic electronic properties and low scattering due to absence of grain boundaries.

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Numerical Studies On Bose-Einstein Condensates, Megan Benkendorf Apr 2024

Numerical Studies On Bose-Einstein Condensates, Megan Benkendorf

Undergraduate Research Conference at Missouri S&T

Bose-Einstein condensate (BEC) is a state of matter near absolute zero temperature for which all atoms lose their individual properties and condense into a macroscopic coherent "super-wave". The superfluidity of BEC has been the focus of active research since the first experimental realization of BEC in 1995. The recent launch of the Cold Atom Laboratory to the space station on May 21, 2018, has once again drawn spotlights to these fascinating properties of BEC. In this project, we will carry out numerical studies to understand the behavior of exciton-polariton BECs. A modified Gross-Pitaevskii equation is used to model the dynamics …

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Enhancing Galaxy Surveys With Machine Learning, Steven Karst Apr 2024

Enhancing Galaxy Surveys With Machine Learning, Steven Karst

Undergraduate Research Conference at Missouri S&T

Applications of machine learning (ML) or artificial intelligence (Al) to problems in astrophysics and cosmology have recently entered a golden era. In response, we have updated two of our recent ML/Al efforts that contribute to galaxy surveys whose main scientific target is to reveal the nature of the Comsic Acceleration or Dark Energy. We first revised our effort to infer cosmological information beyond the survey geometry using Graph Neural Networks (GNNs) to take advantage of supercomputing resources on campus. We then updated our methods for galaxy target selection in the Subaru Prime Focus Spectrograph (PFS) survey with modern reinforcement learning …

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