Engineering Physics Commons^™

Virtual Prototyping Of Liquid Lithium Divertor Concepts, Brennan Arnold

Macalester Journal of Physics and Astronomy

A tokamak divertor must withstand power deposition in excess of 10 MW/m^2 in steady state and much higher in disruptions, enough to destroy nearly any material. In order to handle this extreme heat, there is some interest in using liquid metal flows to continually renew the divertor surface. In this paper, we examine an idea for a divertor with a porous surface that allows liquid lithium flowing through the divertor to percolate to the plasma facing surface. This idea is complicated by magnetohydrodynamic drag, where the stong magnetic fields in the tokamak cause the lithium to flow too ...

Inspection Of Electronics Components For Cryogenic Temperature Operation, Navaneeth Poonthottathil, Frank Krennrich, Amanda Weinstein, Jonathan Eisch, Leonard J. Bond, Dan Barnard, Zhan Zhang, Lucas Koester

Aerospace Engineering Publications

Electronics operating at cryogenic temperatures play a critical role in future science experiments and space exploration programs. The Deep Underground Neutrino Experiment (DUNE) uses a cold electronics system for data taking. Specifically, it utilizes custom-designed Application Specific Integrated Circuits (ASICs). The main challenge is that these circuits will be immersed in liquid Argon and that they need to function for 20+ years without any access. Ensuring quality is critical, and issues may arise due to thermal stress, packaging, and manufacturing-related defects: if undetected, these could lead to long-term reliability and performance problems. This paper reports an investigation into non-destructive evaluation ...

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 ...

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

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

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

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

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

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 ...

Absorbance At The Crabtree, Jaquon Williams

Undergraduate Research Competition

Water scarcity is a growing concern across the world in this document we investigate Crabtree swamp, that’s in Conway, SC. Water absorption is the amount of water taken up by flour to achieve the desired consistency and create a quality end-product. Yet, in this case, we're talking about the Crabtree swamp land area. The goal of this research project is to compare and contrast water absorbance in the area.

The purpose of this study is to naturalize the aquatic ecosystem processes in Crabtree Swamp and improve the survivability of resources of regional significance that have been identified. Resources ...

Investigation Of Trajectory And Control Designs For A Solar Sail To The Moon, Michelle Nadeau

PhD Dissertations and Master's Theses

NASA’s Artemis program and other government and commercial projects are working toward establishing a sustainable human presence on the moon. This thesis investigates the technical feasibility of a solar sail-based spacecraft (sailcraft) as a low-cost method of delivering cargo or science instruments to the moon and demonstrates how this sailcraft could be controlled to change its orbit. The concept is a low-cost, commercial launch vehicle-deployable, CubeSat-based sailcraft with a square sail, assumed attitude control, and a small payload traversing from low-Earth orbit toward the moon with zero propellant use. In this thesis, methods for sailcraft to increase altitude, the ...

Deathtrap, Blake Traylor

Vázquez-Valarezo Poetry Award

I could have titled this one "Bad Trip in an Elevator," but that would twist the poem away from its authenticity. You'll have to trust me on this one: this happened. Not in the usual sense, but in that fiction-is-truth-in-a-funhouse-mirror, postmodern Tim O'Brien sense. And hallucinogens were not involved, nor are they encouraged or condoned. (Do with that Wretched Passive Voice what you will.)

If the word "Deathtrap" didn't amuse me so much, I really could have run with the title "Tired." Or maybe "Very Tired" would have been better. And then there are always the big-hitters ...

Erratum: A Non-Linear Approximate Solution To The Damped Pendulum Derived Using The Method Of Successive Approximations [Georgia Journal Of Science, Vol. 76, No. 2, Article 9], Javier E. Hasbun

Georgia Journal of Science

In an earlier publication [Hill and Hasbun, 2018] considered an approximate solution to the damped pendulum, named the improved modified method of successive approximations (IMMSA), and compared it to an approximation from the work of [Johannessen, 2014]. Here, a correction is made to that comparison due to an error made in calculating Johannessen's approximation.

On-Chip Silicon Photonic Controllable 2 × 2 Four-Mode Waveguide Switch, Cao Dung Truong, Duy Nguyen Thi Hang, Hengky Chandrahalim, Minh Tuan Trinh

Faculty Publications

Multimode optical switch is a key component of mode division multiplexing in modern high-speed optical signal processing. In this paper, we introduce for the first time a novel 2 × 2 multimode switch design and demonstrate in the proof-of-concept. The device composes of four Y-multijunctions and 2 × 2 multimode interference coupler using silicon-on-insulator material with four controllable phase shifters. The shifters operate using thermo-optic effects utilizing Ti heaters enabling simultaneous switching of the optical signal between the output ports on four quasi-transverse electric modes with the electric power consumption is in order of 22.5 mW and the switching time is ...

Surface Acoustic Waves Increase Magnetic Domain Wall Velocity, Anil Adhikari, Shireen Adenwalla

Shireen Adenwalla Papers

Domain walls in magnetic thin films are being explored for memory applications and the speed at which they move has acquired increasing importance. Magnetic fields and currents have been shown to drive domain walls with speeds exceeding 500 m/s. We investigate another approach to increase domain wall velocities, using high frequency surface acoustic waves to create standing strain waves in a 3 micron wide strip of magnetic film with perpendicular anisotropy. Our measurements, at a resonant frequency of 248.8 MHz, indicate that domain wall velocities increase substantially, even at relatively low applied voltages. Our findings suggest that the ...

Stellarator Optimization With Poloidal Field Coils, Haley Wilson, Andrew Ware, Aaron Bader, Chris Hegna

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Stellarators are devices that use magnetic fields to optimize the conditions needed for plasmas to undergo fusion. Unlike tokamaks, stellarators do not rely on a plasma current but can produce a helical magnetic field using only external coils. In a stellarator, the coils surrounding the plasma are called modular coils and those that follow the plasma are called poloidal field coils. Modular coils can be difficult to build if they are too complex. An effort is underway to develop coil conditions that meet both physics and engineering constraints. The FOCUS code was developed to flexibly optimize stellarator coil configurations [C ...

Lithium Nickel Borides: Evolution Of [Nib] Layers Driven By Li Pressure, Volodymyr Gvozdetskyi, Yang Sun, Xin Zhao, Gourab Bhaskar, Scott L. Carnahan, Colin P. Harmer, Feng Zhang, Raquel A. Ribeiro, Paul C. Canfield, Aaron J. Rossini, Cai-Zhuang Wang, Kai-Ming Ho, Julia V. Zaikina

Chemistry Publications

Here we show the effect of Li chemical pressure on the structure of layered polymorphs with LiNiB composition: RT-LiNiB (room temperature polymorph) and HT-LiNiB (high temperature polymorph), resulting in stabilization of the novel RT-Li1+xNiB (x ∼ 0.17) and HT-Li1+yNiB (y ∼ 0.06) phases. Depending on the synthesis temperature and initial Li content, precisely controlled via hydride route synthesis, [NiB] layers undergo structural deformations, allowing for extra Li atoms to be accommodated between the layers. In situ variable temperature synchrotron and time-dependent laboratory powder X-ray diffraction studies suggest Li step-wise deintercalation processes: RT-Li1+xNiB → RT-LiNiB (high temp.) → LiNi3B1.8 ...

Treated Hfo2 Based Rram Devices With Ru, Tan, Tin As Top Electrode For In-Memory Computing Hardware, Yuvraj Dineshkumar Patel

Theses

The scalability and power efficiency of the conventional CMOS technology is steadily coming to a halt due to increasing problems and challenges in fabrication technology. Many non-volatile memory devices have emerged recently to meet the scaling challenges. Memory devices such as RRAMs or ReRAM (Resistive Random-Access Memory) have proved to be a promising candidate for analog in memory computing applications related to inference and learning in artificial intelligence. A RRAM cell has a MIM (Metal insulator metal) structure that exhibits reversible resistive switching on application of positive or negative voltage. But detailed studies on the power consumption, repeatability and retention ...

Drawing Parallels In Art Science For Collaborative Learning: A Case Study, Karen Westland

The STEAM Journal

This research paper explores drawing as a tool to facilitate interdisciplinary practice. Outlined is the personal experience of PhD researcher [name removed] in their physics/craft research project, combined with thoughts and opinions from collaborators gathered through group discursive interviews. Interdisciplinary projects face interpersonal and conceptually ambiguous challenges which can be addressed through adopting drawing techniques for educational purposes. Findings highlight that drawing can assist across a breadth of applications as a learning tool for everyone, regardless of drawing ability, to improve the functionality of collaborative projects. Specifically, drawing combined with other communication techniques develops a performative communicative approach that ...

Numerical Simulation Of Nonlinear Vibrations Of Discrete Mass With Harmonic Force Perturbation, M. Yusupov, B. A. Akhmedov, Olga Karpova

Acta of Turin Polytechnic University in Tashkent

The problem of vibration of a single-mass system under the force excitation of vibration associated with a fixed base by a weightless nonlinear viscoelastic spring is considered. To take into account the rheological properties of the spring material, the Boltzmann-Volterra principle was used. Mathematical models of the problem under consideration are obtained, which are described by integro-differential equations. A solution method based on the use of quadrature formulas has been developed and a computer program has been compiled on its basis, the results obtained are presented in the form of graphs. The influence of nonlinear and rheological properties of a ...