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Large Scale Grid Integration Of Wind And Solar Power With Storage, Nicholas Moore 2020 Macalester College

Large Scale Grid Integration Of Wind And Solar Power With Storage, Nicholas Moore

Macalester Journal of Physics and Astronomy

The current energy grid in the United States is dominated by carbon intense energy generation methods that are based on production when and where it is required. However, solar and wind power have proved themselves as the most promising carbon free energy generation sources. Due to the unpredictable and uncontrollable nature of energy production from solar and wind, large scale integration of these resources into the electric grid will require robust storage capacity. In this project, we model the energy grid of the Midcontinent Independent System Operator (MISO) energy region with high concentrations of solar and wind power to analyze ...


Deposition Of Tin For Battery And Supercapacitor Electrodes For Energy Storage, Kieran M. Liming 2020 Macalester College

Deposition Of Tin For Battery And Supercapacitor Electrodes For Energy Storage, Kieran M. Liming

Macalester Journal of Physics and Astronomy

Titanium Nitride (TiN) can be sputtered into a thin film, and is a promising component for battery and supercapacitor electrodes. This research explored the relationship between Nitride partial pressure and film characteristics. We sputtered TiN into thin films in a low vacuum environment at tempuratures of approximately 70o C. Most films were deposited over the course of one hour including a five minute presputtering period where the substrate was covered. We found that film thickness, system voltage, and film restivitiy to be a function of N2 partial pressure.


Searching For Doublet Vectorlike Leptons Using The Atlas Particle Detector, Brynn Keller 2020 Macalester College

Searching For Doublet Vectorlike Leptons Using The Atlas Particle Detector, Brynn Keller

Macalester Journal of Physics and Astronomy

Vectorlike leptons are a simple extension of the standard model, akin to a fourth family of leptons. This paper describes aspects of the preparation for a search for VLLs at an ATLAS particle collider. During this research, signal and control regions were determined with use of a Monte Carlo simulation in order to best estimate where to measure different kinds of background and where to search for a potential signal. These signal and control regions were optimized with respect to MET, LT, and number of light and heavy leptons with a goal of a 95\% confidence limit.


A Search For Pulsars Towards The Galactic Center, Jacob W. Hetrick, Kunal Mooley, Preshanth Jagannathan 2020 Macalester College

A Search For Pulsars Towards The Galactic Center, Jacob W. Hetrick, Kunal Mooley, Preshanth Jagannathan

Macalester Journal of Physics and Astronomy

We present observations from two separate methods for observing the Galactic Center in an attempt to characterize its pulsar and neutron star populations. A persistent puzzle of the past 20 years has been the lack of pulsar detections towards the Galactic Center, specifically within a few parsecs of the central supermassive black hole Sgr A*. This object is bright in the total intensity of its polarized emission, but is very weakly linearly polarized. We take advantage of these circumstances in an experimental search technique where we utilize the Faraday effect in an attempt to detect high rotation measure (RM) point ...


Modeling Scavenging For A Hydraulic Free-Piston Engine, Nathan Davies 2020 Macalester College

Modeling Scavenging For A Hydraulic Free-Piston Engine, Nathan Davies

Macalester Journal of Physics and Astronomy

The hydraulic free-piston engine at the University of Minnesota offers a solution to improve the hydraulic efficiency and reduce emission output of off-road vehicles. We developed a MATLAB Simulink model to track the pressure, temperature, and mass profile of the fuel within the cylinder during operation. By varying different initial conditions of our model, we found that a higher intake manifold pressure and larger bottom dead center location results in higher scavenging efficiency. These results can be used to improve the controller of this engine and better maintain stable operation.


Alfalfa Harvest: Hi Imaging And 3d Modeling Of Candidate Local Group Dwarf Galaxies, Lilly Bralts-Kelly, Susie Paine, Elizabeth A. K. Adams, John M. Cannon 2020 Macalester College

Alfalfa Harvest: Hi Imaging And 3d Modeling Of Candidate Local Group Dwarf Galaxies, Lilly Bralts-Kelly, Susie Paine, Elizabeth A. K. Adams, John M. Cannon

Macalester Journal of Physics and Astronomy

Isolated neutral hydrogen (HI) clouds, or "ultra-compact high-velocity clouds" (UCHVCs), form a small subset of detections by the Arecibo Legacy Fast ALFA (ALFALFA) blind extragalactic survey. These systems, if located within ~1 Mpc, would populate the lowest-mass end of the HI mass function. Subsequent optical imaging has revealed that some of these UCHVCs harbor associated (thought sparse) stellar populations, suggesting that they may be some of the most extreme galaxies known in the Local Volume, with properties akin to ultra-faint dwarf galaxies but with significant neutral gas reservoirs. In this work, we investigate the neutral hydrogen properties of six UCHVC ...


Leoncino And Ugc 5186, Josh Bartz 2020 Macalester College

Leoncino And Ugc 5186, Josh Bartz

Macalester Journal of Physics and Astronomy

AGC 198691 is commonly known as the Leoncino Dwarf and is one of the most metal poor galax- ies known. An Arecibo observation in 2011 first suggested that Leoncino could be gravitationally interacting with its neighbor UGC 5186. In this paper new VLA data is used to examine the H I com- ponent of both galaxies to determine their gravitational relationship. Although the VLA could not confirm intragalactic gas seen by Aricebo, the H I density and velocity components are strong indirect evidence of gravitational interaction. UGC 5186 has a large gaseous arm reaching in the direction of Leoncino. Additionally ...


Coherent Captain Mills: The Search For Sterile Neutrinos, Ashley Elliott, Jeramy Gordon, Jonah Greenwood, Rachel Lake, Ryder Moreno, Emily Strawn, Kate Walker 2020 Embry-Riddle Aeronautical University

Coherent Captain Mills: The Search For Sterile Neutrinos, Ashley Elliott, Jeramy Gordon, Jonah Greenwood, Rachel Lake, Ryder Moreno, Emily Strawn, Kate Walker

Discovery Day - Prescott

The observation of neutrino oscillations confirms that the active neutrinos (νe, νμ, ντ) are comprised of three mass eigenstates with Δm2 values between 10-3 to 10-5 eV2 . However, a persistent phenomenon has been observed at LSND, MiniBooNE and other shortbaseline experiments (SBE) where Δm2 ~ 1eV2 and is not compatible with the current mixing between mass eigenstates. However, a 4th neutrino, a sterile neutrino (νs) that doesn’t participate in weak interactions could explain the phenomena observed as SBE’s. An experiment has been constructed at TA-53 at Los Alamos National Laboratory to investigate this large Δm2 ~ 1eV2 and determine conclusively ...


Comparison Of The Vibrational Modes Of Thiolated Gold Nanoparticles Undergoing Core-Conversions Via Raman Spectroscopy, William Gregory Cannella Jr. 2020 University of Mississippi

Comparison Of The Vibrational Modes Of Thiolated Gold Nanoparticles Undergoing Core-Conversions Via Raman Spectroscopy, William Gregory Cannella Jr.

Honors Theses

In this project, the vibrational characteristics/vibrational modes are explored via Raman Spectroscopy for thiolated-gold nanoparticles. This class of compounds is also known as gold nanoparticles (AuNPs). They remain of great interest in research areas such as catalysis, gold dependent nanoelectronics, drug delivery, and sensing, due to their unique size-dependent optical, chiroptical, and electronic properties. Vibrational spectroscopy of thiolated gold nanoparticles are oftentimes considered nontrivial as the compounds strongly absorb light in the visible region of the electromagnetic spectrum, are generally considered weak scatterers, and give off large amounts of fluorescence. This combined with their black appearance, susceptibility to localized ...


Heel Down And Toe-Off Time Measured With Ultrasonic Doppler System And Force Plate Sensor, Sabin Timsina 2020 University of Mississippi

Heel Down And Toe-Off Time Measured With Ultrasonic Doppler System And Force Plate Sensor, Sabin Timsina

Honors Theses

Collie Box is a medical device that measures the gait parameters of the person walk- ing in front of it. This device uses the Ultrasonic Doppler system to extract the heel-contact and toe-off times of a person walking within the range of 2-10 meters. These times are used to determine the leg’s swing phase and double stance times. The ultrasonic transducer of 10mm diameter is driven at 40kHz. At the time of the heel-contact and toe-off, foot velocity is zero while the torso part of the human body is still in motion. The wide directivity of 10mm diameter ultrasonic ...


Investigatin Actin-Myosin Mechanics To Model Heart Disease Using Fluorescence Microscopy And Optical Trapping, Justin Edward Reynolds 2020 University of Mississippi

Investigatin Actin-Myosin Mechanics To Model Heart Disease Using Fluorescence Microscopy And Optical Trapping, Justin Edward Reynolds

Honors Theses

Hypertrophic cardiomyopathy (HCM) is a hereditary disease in which the myocardium becomes hypertrophied, making it more difficult for the heart to pump blood. HCM is commonly caused by a mutation in the β-cardiac myosin II heavy chain. Myosin is a motor protein that facilitates muscle contraction by converting chemical energy from ATP hydrolysis into mechanical work and concomitantly moving along actin filaments. Optical tweezers have been used previously to analyze single myosin biophysical properties; however, myosin does not work as a single unit within the heart. Multiple myosin interacts to displace actin filaments and do not have the same properties ...


Disorder By Design: A Data-Driven Approach To Amorphous Semiconductors Without Total-Energy Functionals, Dil K. Limbu, Stephen R. Elliott, Raymond Atta-Fynn, Parthapratim Biswas 2020 University of Southern Mississippi

Disorder By Design: A Data-Driven Approach To Amorphous Semiconductors Without Total-Energy Functionals, Dil K. Limbu, Stephen R. Elliott, Raymond Atta-Fynn, Parthapratim Biswas

Faculty Publications

X-ray diffraction, Amorphous silicon, Multi-objective optimization, Monte Carlo methods. This paper addresses a difficult inverse problem that involves the reconstruction of a three-dimensional model of tetrahedral amorphous semiconductors via inversion of diffraction data. By posing the material-structure determination as a multiobjective optimization program, it has been shown that the problem can be solved accurately using a few structural constraints, but no total-energy functionals/forces, which describe the local chemistry of amorphous networks. The approach yields highly realistic models of amorphous silicon, with no or only a few coordination defects (≤1%), a narrow bond-angle distribution of width 9–11.5°, and ...


Automating 35mm Photographic Film Digitization: X-Y Table Capture System Design And Assessment, Michael J. Bennett 2020 University of Connecticut - Storrs

Automating 35mm Photographic Film Digitization: X-Y Table Capture System Design And Assessment, Michael J. Bennett

Published Works

35mm still image formats are some of the most abundant photographic film types in cultural heritage collections. However, their special handling needs coupled with high resolution digital capture requirements have traditionally posed logistical constraints with regard to the formats’ digitization at scale. Through the use of a programmable X-Y table camera capture system, both slide and strip 35mm photographic film can be digitized in an automated fashion following Federal Agencies Digitization Guidelines (FADGI).


Numerical Modeling Of Magnetic Fields For Mirror Neutron Search Experiment, Adam Johnston 2020 University of Tennessee, Knoxville

Numerical Modeling Of Magnetic Fields For Mirror Neutron Search Experiment, Adam Johnston

Pursuit - The Journal of Undergraduate Research at the University of Tennessee

This paper will outline the configuration of 3D magnetic field model simulated from electric current sources using MATLAB. The model is using 3D arrays allowing for quick and accurate numerical approximations of Bio-Savart integrals, of error < , modeling the behavior of a magnetic field due to current carrying wires. We will discuss the development of a 3D magnetic field configuration produced by the current carrying wires around a large 2.5 m diameter vacuum beam tube in the proposed mirror neutron search experiment at High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). The simulations demonstrate that the magnetic field with uniformity better than ± 2.5 mG that will allow for optimal results in experiment within the controlled range of net magnetic field magnitudes |B| 500 mG and in the large vacuum tube along 20-m neutron flight path can be achieved for an approximately 6 cm radius section at the center of the tube.


Finding Strong Gravitational Lenses With Residual Neural Networks, Christopher Storfer, Andrew Pilon, Varun Ravi, Matthew Domingo 2020 University of San Francisco

Finding Strong Gravitational Lenses With Residual Neural Networks, Christopher Storfer, Andrew Pilon, Varun Ravi, Matthew Domingo

Creative Activity and Research Day - CARD

Measuring gravitational lensing by galaxies is the only way to directly study the elusive dark matter. However, gravitational lensing is a very rare phenomenon (~1 in 10,000 galaxies). Our goal is to find new strong gravitational lenses using deep neural networks (“neural nets”). We train our neural nets on a hand-labeled set of images, consisting of both lenses and non-lenses (“the training sample”). We then apply the trained neural nets to a “validation set” to assess the accuracy and precision of its predictions. Given the rarity of lenses, we cannot tolerate a false positive rate higher than 0.1 ...


Physics 516: Electromagnetic Phenomena (Spring 2020), Philip C. Nelson 2020 University of Pennsylvania

Physics 516: Electromagnetic Phenomena (Spring 2020), Philip C. Nelson

Department of Physics Papers

These course notes are made publicly available in the hope that they will be useful. All reports of errata will be gratefully received. I will also be glad to hear from anyone who reads them, whether or not you find errors: pcn@upenn.edu.


Design Of Submicron Structured Guided-Mode-Resonance Near-Infrared Polarizer, Marzia Zaman 2020 University of Arkansas, Fayetteville

Design Of Submicron Structured Guided-Mode-Resonance Near-Infrared Polarizer, Marzia Zaman

Theses and Dissertations

The objective of this research is to design a larger submicron linear polarizer in the near-infrared wavelength range with a wide bandwidth which can be fabricated using the conventional thin-film microfabrication technology to reduce cost. For this purpose, a gold (Au) wire-grid transmission-type transverse-magnetic (TM) polarizer and a silicon (Si) wire-grid reflection-type TM polarizer, were designed using the guided-mode-resonance filter. The Au wire-grid TM polarizer of 700nm grating width and 1200nm grating period has 95% transmittance at 2400nm, more than 1000nm resonance peak bandwidth, and an extinction ratio (ER) of around 300 with a moderated level of sidebands. The 700nm ...


Symmetry And Interface Considerations For Interactions On Mos2, Prescott E. Evans 2020 University of Nebraska–Lincoln

Symmetry And Interface Considerations For Interactions On Mos2, Prescott E. Evans

Theses, Dissertations, and Student Research: Department of Physics and Astronomy

The critical role of symmetry, in adsorbate-MoS2 interactions, has been demonstrated through a variety of electronic structure, topology, and catalytic studies of MoS2 and MoS2 composites.A combination of density functional theory and experiment exhibiting diiodobenzene isomer dependent adsorption rates highlight frontier orbital symmetry as key to adsorption on MoS2. It is clear that the geometry and symmetry of MoS2 influences the creation and stability of surface defects, that in turn affect catalytic activity and a myriad of other applications. We have shown that surface reactions such the methanol to methoxy reaction can create defects ...


Fabrication Of Suspended Microbolometers On Soi Wafers, Isaac Maxfield 2020 Utah State University

Fabrication Of Suspended Microbolometers On Soi Wafers, Isaac Maxfield

Physics Capstone Projects

A bolometer is a device to measure radiation energy by converting photon energy into heat on an isolated absorber. We plan to use carbon-nanotube (CNT) based absorber to enhance the photon absorption. The absorber is a few microns in size and is suspended with micron-sized bridges which also support metal lines for electrical measurements.


Synthesis Of Graphene By Liquid Precursors At Lower Temperatures, Clayton Hansen 2020 Utah State University

Synthesis Of Graphene By Liquid Precursors At Lower Temperatures, Clayton Hansen

Physics Capstone Projects

Benzene, toluene, and xylene can be liquid precursors for graphene and carbon nanotube synthesis. However, the growth mechanisms can have greater variances for different carbon allotropes. In the case of graphene, Cu can be the catalyst for dehydrogenation and provides a weakly-coupled substrate for 2-dimensional graphene nucleation and growth. In the case of carbon nanotubes, Fe nanoparticles are essential to catalyze the C-C bonds breaking and dissolve carbon before the precipitation of a graphene cap over the catalyst particle where a tube forms. Controlling the precursor feed rate is crucial for a successful synthesis. In this research, we developed a ...


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