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Designing Cryogenic Strain Device For 2d Materials, Jake Carter 2021 University of Arkansas, Fayetteville

Designing Cryogenic Strain Device For 2d Materials, Jake Carter

Mechanical Engineering Undergraduate Honors Theses

The Churchill lab working within the Physics Department at the University of Arkansas is working to create important quantum states including weak topological insulators (TIs) through the use of symmetry engineering and topological electronic states in two-dimensional (2D) crystals of WHM materials. Experimental results of these topological states have been obstructed due to the difficulty to perform controlled in situ strain. This project strives to create a mount to utilize a piezoelectric nanopositioner within cryostats achieving an in situ strain that creates the quantum states the lab is looking to observe. This report also examines the necessary equations to determine ...


Design And Control Of A Peristaltic Pump To Simulate Left Atrial Pressure In A Conductive Silicone Model, Jeremy Collins 2021 University of Arkansas, Fayetteville

Design And Control Of A Peristaltic Pump To Simulate Left Atrial Pressure In A Conductive Silicone Model, Jeremy Collins

Mechanical Engineering Undergraduate Honors Theses

According to the CDC, atrial fibrillation is responsible for more than 454,000 hospitalizations and approximately 158,000 deaths per year. A common treatment for atrial fibrillation is catheter ablation, a process in which a long flexible tube is guided through the femoral artery and to the source of arrhythmia in the heart, where it measures the electrical potential at various locations and converts problematic heart tissue to scar tissue via ablation. This paper details the design and control of a low-cost ($400) peristaltic pump system using repetitive control to replicate blood pressure in the left atrium in a conductive ...


The Effects Of Materials And Profiles Of Gratings On Diffraction Spectra, Brock Halling 2021 Utah State University

The Effects Of Materials And Profiles Of Gratings On Diffraction Spectra, Brock Halling

Physics Capstone Projects

Diffraction patterns can be made either by transmitting or reflecting light from a grating which is an array of parallel lines (rulings) with a fixed periodicity. Elementary optical treatment of diffraction gratings only describes diffraction angles as a function of periodicity of the grating. However, we have observed that the profile and materials of the grating do affect the diffraction pattern. In this study, I investigated the correlation between the grating profiles obtained by scanning electron microscopy and the materials of the grating (polymer and silicon dioxide) and the spectra as a function of the diffraction angle. An optical spectrometer ...


Comparisons Of Mesospheric Temperatures Between 70 And 110 Km: Usu Lidar, Nasa's Timed Satellite, And The Msis2 Empirical Model, David M. Collins 2021 Utah State University

Comparisons Of Mesospheric Temperatures Between 70 And 110 Km: Usu Lidar, Nasa's Timed Satellite, And The Msis2 Empirical Model, David M. Collins

Physics Capstone Projects

Earth’s atmosphere can be characterized by its temperature structure, dividing the atmosphere into natural discrete regions. The mesosphere (50 to ~100 km) has been the least studied. Rayleigh-scatter lidars (RSL) and rockets can obtain local, high-resolution measurements above one spot, while satellites looking almost horizontally obtain global measurements. These two methods of measuring atmospheric conditions are compared using the USU RSL and the SABER instrument on NASA’s TIMED satellite. These measurements were graphed to show four sets of temperatures from several sources in the atmospheric region 70 km to 110 km above USU. The results show similar temperatures ...


Curved Spacetime In The Causal Set Approach To Quantum Gravity, Ayush Dhital 2021 University of Mississippi

Curved Spacetime In The Causal Set Approach To Quantum Gravity, Ayush Dhital

Honors Theses

Causal Set theory is an approach to quantum gravity. In this approach, the spacetime continuum is assumed to be discrete rather than continuous. The discrete points in a causal set can be seen as a continuum spacetime if they can be embedded in a manifold such that the causal structure is preserved. In this regard, a manifold can be constructed by embedding a causal set preserving causal information between the neighboring points. In this thesis, some of the fundamental properties of causal sets are discussed and the curvature and dimension information of Minkowski, de Sitter, and Anti-de Sitter spaces is ...


Developing Electron Beam Lithography At Nanoscale Device Laboratory, Din Pašić 2021 Utah State University

Developing Electron Beam Lithography At Nanoscale Device Laboratory, Din Pašić

Physics Capstone Projects

At the Nanoscale Device Laboratory, we can routinely create patterns with a minimum linewidth of 800 nm using photolithography. However, to create photonic devices, the pattern size must be smaller than the wavelength of visible light (400 to 800 nm). Dedicated electron beam writers can achieve a sub-10 nm linewidth, but this system is beyond our reach. In this project, we plan to use a Nanometer Pattern Generation System connected to a Quanta 650 scanning electron microscope to perform e-beam lithography. After setting up a computer to run the NPGS system, and establishing communications with the SEM, we experimented with ...


Fundamental Aspects Of Black Holes, Jacob Fisher Ciafre 2021 Utah State University

Fundamental Aspects Of Black Holes, Jacob Fisher Ciafre

All Graduate Plan B and other Reports

The literature study here seeks to present the foundations of black hole physics in General Relativity. The report includes a discussion of the Kerr black hole metric, black hole entropy, particle creation, the laws of black hole mechanics, and a bilinear mass formula for the Kerr-Newman black hole solution.


Composite Gravity In Curved Spacetime, Austin Batz 2021 William & Mary

Composite Gravity In Curved Spacetime, Austin Batz

Undergraduate Honors Theses

This work presents the development of a quantum theory of gravity motivated by diffeomorphism-invariance and background-independence. A composite graviton state that satisfies the linearized Einstein’s field equations has been identified via perturbative expansion about a curved vacuum spacetime. The emergence of this gravitational interaction is discussed, as well as cancellation of tadpoles and treatment of ultraviolet divergences via dimensional regularization. In other words, the formalism of quantum field theory is used to identify a gravitational interaction as an emergent phenomenon rather than as a fundamental aspect of nature. The lattice is proposed as a candidate for a physical regulator ...


Simulation And Optimization Of Kinematics Measurements For The Moller Parity-Violating Electron-Electron Scattering Experiment, Lauren Carver 2021 William & Mary

Simulation And Optimization Of Kinematics Measurements For The Moller Parity-Violating Electron-Electron Scattering Experiment, Lauren Carver

Undergraduate Honors Theses

This report describes the optimization of the sieve collimator that will be used for the MOLLER experiment at Jefferson Laboratory. The MOLLER experiment seeks to study the parity-violating asymmetry in electron-electron elastic scattering. For this project, Monte Carlo simulations were run using a GEANT4 simulation package, which includes the main geometry of the proposed experiment, and the essential physics reaction processes. A sieve collimator was added to the simulated geometry. This collimator has pin-hole openings to select scattered electrons at certain locations (radial and azimuthal positions) corresponding to specific scattering angles (theta, and phi). Analysis of the simulated data were ...


Topology Of The O(3) Non-Linear Sigma Model Under The Gradient Flow, Stuart Thomas, Christopher Monahan 2021 William & Mary

Topology Of The O(3) Non-Linear Sigma Model Under The Gradient Flow, Stuart Thomas, Christopher Monahan

Undergraduate Honors Theses

Quantum field theory is an extraordinarily successful framework that describes phenomena in particle physics and condensed matter. The O(3) non-linear sigma model (NLSM) is a specific theory used in both of these fields, describing ferromagnets and acting as a prototype for the strong nuclear force. It features topologically stable configurations known as instantons which cannot continuously evolve to the ground state. The topological susceptibility is a parameter that describes this stability and is predicted to vanish in physical theories, however numerical simulations find that the topological susceptibility diverges in the continuum limit. This issue has motivated the application of ...


Modeling The Problem Of Integral Geometry On A Family Of Hyperbolic And Spherical Curves, Azamat Pirimbetov, N. Uteuliev, G. Djaykov 2021 Karakalpak State University

Modeling The Problem Of Integral Geometry On A Family Of Hyperbolic And Spherical Curves, Azamat Pirimbetov, N. Uteuliev, G. Djaykov

Karakalpak Scientific Journal

The problems of integral geometry in a strip on a family of curves of hyperbolic and spherical type are considered which have numerous applications in problems of geophysics, thermoacoustic and photoacoustic tomography. Explicit formulas are obtained for the Fourier image of the solution of integral geometry problems in the class of smooth compactly supported functions. Further, the obtained formulas are investigated for stability using numerical methods. To solve the problems, algorithms are constructed. Numerical and graphical results of applying these algorithms to solving the problems are presented.


382— Wiyn Open Cluster Study: Ubvri Photometry Of Ngc 2204, Kylie Snyder, Dante Scarazzini 2021 SUNY Geneseo

382— Wiyn Open Cluster Study: Ubvri Photometry Of Ngc 2204, Kylie Snyder, Dante Scarazzini

GREAT Day

The purpose of this project was to study the open star cluster NGC2204 using images taken at Kitt Peak National Observatory using the WIYN 0.9m telescope. These images were analyzed photometrically with the intention of determining the reddening, metallicity, age, and distance modulus of the star cluster. Each image was analyzed using software that determined the point spread function and applied that function to determine the magnitude of each star in that image. These magnitudes were taken for each filter, UBVRI, and then combined and averaged to create a single catalog. Standard stars, taken on the same night, were ...


Improving Skills In Computer Methods: Introductory Toolkit To Python For Undergraduate Physics Majors, Erin O'Donnell, Melissa Rasmussen 2021 Utah State University

Improving Skills In Computer Methods: Introductory Toolkit To Python For Undergraduate Physics Majors, Erin O'Donnell, Melissa Rasmussen

Physics Capstone Projects

The computer-based curriculum for undergraduate physics students before 2019 struggled to stay current and applicable. When the course was created in the early 2000s, MathCad was used daily by many physicists. As computer’s and their computational abilities have grown exponentially, so have programming languages and applications. Now in the late 2010s/early 2020s, Excel, Python, and Mathematica are some of the most common computer appliques. To address this, we created toolkits to give undergraduate physicists the experience for future classes, careers, and graduate school. This paper focuses on the process for creating the Python toolkit and overall class setup ...


Investigating The Angular Momentum Of Dusty Plasma Multi-Rings, Isaac M. Long, Kiser Z. Colley 2021 Ohio Northern University

Investigating The Angular Momentum Of Dusty Plasma Multi-Rings, Isaac M. Long, Kiser Z. Colley

ONU Student Research Colloquium

Multi-ring dusty plasma systems were created using a grooved rf electrode. These complex plasma systems had distinct sections consisting of a certain number of rings (1 ring section, 2 ring section, 3 ring section, 4 ring section). These rings had the tendency to rotate azimuthally about the center of the electrode, which allowed for a sectional angular velocity (ω) to be calculated. It was determined that as the number of dust rings (therefore the mass) increased, ω decreased which agrees with conservation of angular momentum. The pressure was also varied and it was found that as pressure increased, the width ...


Simulation Of Optical Properties Of Dielectric Layers From Visible To Near Infrared Spectral Range, Andrew Cochran, Cory Conkel 2021 Ohio Northern University

Simulation Of Optical Properties Of Dielectric Layers From Visible To Near Infrared Spectral Range, Andrew Cochran, Cory Conkel

ONU Student Research Colloquium

Optical properties of dielectrics play a critical role in various applications including the design and manufacture of optical components & devices such as detectors, filters, imagers, lenses, optical coatings, photonic crystals, sensors and waveguides, and solar cells. Radiative properties of varying thicknesses of different dielectrics such as Aluminum Oxide (Al2O3), Silicon Dioxide (SiO2), Indium Tin Oxide (ITO), Magnesium Fluoride (MgF2) and Silicon Nitride (Si3N4) have been simulated and compared in the range of visible to near infrared by mathematical modelling using MATLAB simulations. The results of the evolution of the radiative properties, as a function of dielectric material thickness, on silicon ...


E. Coli And Total Coliform, Emilio Wilson 2021 Coastal Carolina University

E. Coli And Total Coliform, Emilio Wilson

Undergraduate Research Competition

Water is important because we use it for our everyday use, whether it's for drinking, bathing, or for our enjoyment. Pollution causes the environment to have a harmful effect, which is usually caused by microorganisms (bacteria) Some of those Bacteria include E. coli and Total Coliform. They're mainly found in the intestines of humans, in animals, in water, and also found in the soil. Most of these bacteria are harmless but it can provide you with symptoms of diarrhea, vomiting, and stomach cramps. When water comes in contact with feces, humans, or any living organism, the water is ...


Monitoring Nitrogen Levels At 11th Ave. N Surfside Beach, Sc, Kyle LaVoie 2021 Coastal Carolina University

Monitoring Nitrogen Levels At 11th Ave. N Surfside Beach, Sc, Kyle Lavoie

Undergraduate Research Competition

This research was done to monitor Ammonia, Nitrite, and Nitrate which are measured to assess if they were within safe levels according to the Environmental Protection Association(EPA). Ammonia, Nitrite, and Nitrate are important indicators to the amount of each that could end up in a public water supply. To much Nitrate can cause excess algae growth in lakes and is unhealthy in large amounts for humans, mainly children. Samples were tested using Ammonia test strips and Nitrite and Nitrate test strips. 242 samples were collected between May 27th, 2010 and January 26th, 2021 at 11th Ave. N Surfside Beach ...


Water Monitoring At Ccu (Conductivity, Ph, Do), Gage Campbell 2021 Coastal Carolina University

Water Monitoring At Ccu (Conductivity, Ph, Do), Gage Campbell

Undergraduate Research Competition

Monitoring water quality is important for human health. This study focuses on the 544 West site and the parameters conductivity, pH, and dissolved oxygen (DO). Data used is from Oct. 2011 through Nov. 2020 on the Coastal Carolina University campus and used an Orion™ A329 multimeter. 741 samples were collected for Conductivity, with an average of 407.8 uS/cm (145.8 uS/cm - 690.7 uS/cm). 738 samples were collected for pH, with an average of 7.15 (6.09 - 8.11). All data fell within the SC DHEC water quality standard of pH which is no lower ...


Detecting Radium-226 In Submarine Groundwater Discharge, Rashaun Davis 2021 Coastal Carolina University

Detecting Radium-226 In Submarine Groundwater Discharge, Rashaun Davis

Undergraduate Research Competition

Studies have been done to see if abundance of neutrinos have an effect on the decay rate of radioactive nuclei. Questions regarding the proximity of the sun and the concentration of the flux of neutrinos as a result, have emerged due to there being more counts in the winter when the sun is closer versus there being less counts in the summer when the sun is farther away. Other studies say that the cause of the difference in counts are more local, as in the environmental conditions like temperature and various background radiation that interferes with the counts of the ...


Monitoring Chlorophyll A And Pheophytin At Crabtree Swamp, James Blankenship 2021 Coastal Carolina University

Monitoring Chlorophyll A And Pheophytin At Crabtree Swamp, James Blankenship

Undergraduate Research Competition

The two chemicals compound we will be looking at include Chlorophyll A and Pheophytin. These two chemicals are common in most waters around the world. While they are helpful for the ecosystem, like most everything, having too much can also be harmful. Having a high concentrate of Chlorophyll A can result in foul smell and green scum on the bottom and surface of water. Likewise, pheophytin can be harmful when it comes to dissolving oxygen in water. This can result in erosion around the water source and can lead to unwanted chemicals in water (4). The results discussed will show ...


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