Other Physics Commons^™

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …

Performing Near Field Acoustic Holography Scans For The Purpose Of Finding The Acoustic Impedance Of A Violin, Zamara Tomko

Student Research, Papers, and Creative Works

This project aimed to measure the acoustic impedance of the violin so that the violin can be better understood from an acoustic standpoint. Near field acoustic holography scans are to be conducted at the open A string resonance of the violin (440 Hz). Pressure microphones along the back plate of the violin allow pressure and particle velocity to be measured, and with that, the acoustic impedance to be calculated and mapped in 1 cm x 1cm increments. This work presents a guide for this procedure. The set-up method and materials used are detailed and the analysis and computations of values …

Diffusion Doping Of Cobalt In Rod-Shape Anatase Tio2 Nanocrystals Leads To Antiferromagnetism†, Shahzahan Mia, Shelton J.P. Varapragasam, Aravind Baride, Choumini Balasanthiran, Balamurugan Balasubramanian, Robert M. Rioux, James D. Hoefelmeyer

Nebraska Center for Materials and Nanoscience: Faculty Publications

Cobalt(II) ions were adsorbed to the surface of rod-shape anatase TiO2 nanocrystals and subsequently heated to promote ion diffusion into the nanocrystal. After removal of any remaining surface bound cobalt, a sample consisting of strictly cobalt-doped TiO2 was obtained and characterized with powder Xray diffraction, transmission electron microscopy, UV-visible spectroscopy, fluorescence spectroscopy, X-ray photoelectron spectroscopy, SQUID magnetometry, and inductively-coupled plasma atomic emission spectroscopy. The nanocrystal morphology was unchanged in the process and no new crystal phases were detected. The concentration of cobalt in the doped samples linearly correlates with the initial loading of cobalt(II) ions on the nanocrystal surface. Thin …

Detection Of Decoupled Surface And Bulk States In Epitaxial Orthorhombic Sriro3 Thin Films, Prescott E. Evans, Takashi Komesu, Le Zhang, Ding-Fu Shao, Andrew J. Yost, Shiv Kumar, Eike F. Schwier, Kenya Shimada, Evgeny Y. Tsymbal, Xia Hong, P. A. Dowben

Peter Dowben Publications

We report the experimental evidence of evolving lattice distortion in high quality epitaxial orthorhombic SrIrO3(001) thin films fully strained on (001) SrTiO3 substrates. Angle-resolved X-ray photoemission spectroscopy studies show that the surface layer of 5 nm SrIrO3 films is Sr–O terminated, and subsequent layers recover the semimetallic state, with the band structure consistent with an orthorhombic SrIrO3(001) having the lattice constant of the substrate. While there is no band folding in the experimental band structure, additional super-periodicity is evident in low energy electron diffraction measurements, suggesting the emergence of a transition layer with crystal symmetry evolving from the SrTiO3 substrate …

Manipulation Of The Molecular Spin Crossover Transition Of Fe(H2b(Pz)2)2(Bipy) By Addition Of Polar Molecules, Paulo S. Costa, Guanhua Hao, Alpha T. N'Diaye, Lucie Routaboul, Pierre Braunstein, Xin Zhang, Jian Zhang, Thilini K. Ekanayaka, Qin Yin Shi, V. L. Schlegel, Bernard Doudin, Axel Enders, Peter Dowben

Peter Dowben Publications

The addition of various dipolar molecules is shown to affect the temperature dependence of the spin state occupancy of the much studied spin crossover Fe(II) complex, [Fe{H2B(pz)2}2(bipy)] (pz = pyrazol-1-yl, bipy = 2,2′-bipyridine). Specifically, the addition of benzimidazole results in a re-entrant spin crossover transition, i.e. the spin state starts in the mostly low spin state, then high spin state occupancy increases, and finally the high spin state occupancy decreases with increasing temperature. This behavior contrasts with that observed when the highly polar p -benzoquinonemonoimine zwitterion C6H2(..NH2)2(..O)2 was mixed with [Fe{H2B(pz)2}2(bipy)], which resulted in locking [Fe{H2B(pz)2}2(bipy)] largely into a low …

Launching A New Dimension With 3d Magnetic Nanostructures, Peter Fischer, Dédalo Sanz-Hernández, Robert Streubel, Amalio Fernández-Pacheco

Robert Streubel Papers

The scientific and technological exploration of three-dimensional magnetic nanostructures is an emerging research field that opens the path to exciting novel physical phenomena, originating from the increased complexity in spin textures, topology, and frustration in three dimensions. One can also anticipate a tremendous potential for novel applications with those systems in a magnetic sensor and information processing technologies in terms of improved energy efficiency, processing speed, functionalities, and miniaturization of future spintronic devices. These three-dimensional structures are distinct from traditional bulk systems as they harness the scientific achievements of nanomagnetism, which aimed at lowering the dimensions down to the atomic …

Gas Adsorption In Carbon Nanohorns: Equilibrium And Kinetics, Justin Matthew Petucci

Electronic Theses and Dissertations

A study of gas adsorption has been carried out with the focus of better understanding the relationships between the individual properties of the adsorbent/adsorbate (e.g. material structure, interactions, gas size and shape, etc.) and the overall adsorptive properties of the combined system (e.g. capacity, binding strength, equilibration time, etc.) as a function of thermodynamical variables. This is useful from the perspective of a comprehensive and fundamental understanding as well as for practical applications. The equilibrium regime of adsorption on carbon nanostructure materials (nanohorns, nanotubes, and graphite) is investigated using molecular statics (MS) and grand canonical monte carlo (GCMC) methods for …

The Effect Of Size Upon Haptic Shape Discrimination, Jessica Dukes

Mahurin Honors College Capstone Experience/Thesis Projects

Object shape perception is fundamentally important for daily life. It has been suggested (e.g., Gibson, 1962) that the visual and haptic modalities are equivalent with regards to the ability to perceive shape. Norman et al. (2012) showed that visual and haptic shape discrimination accuracies are indeed comparable. Craddock and Lawson (2009) found that haptic shape discrimination performance was adversely affected by a size change. However, this result was obtained for man-made objects (i.e., bathtubs and benches). The purpose of the current investigation was to determine whether size changes also reduce haptic shape discrimination accuracy for naturally-shaped objects. On any given …

The Paradox Of The Tight Spiral Pass In American Football: A Simple Resolution, Richard H. Price, William C. Moss, Timothy J. Gay

Timothy J. Gay Publications

An American football is a rotationally symmetric object, which, when well-thrown, spins rapidly around its symmetry axis. In the absence of aerodynamic effects, the football would be a torque-free gyroscope and the symmetry/spin axis would remain pointing in a fixed direction in space as the football moved on its parabolic path. When a pass is well-thrown through the atmosphere, however, the symmetry axis remains—at least approximately—tangent to the path of motion. The rotation of the symmetry axis must be due to aerodynamic torque; yet, that torque, at first glance, would seem to have precisely the opposite effect. Here, we explain …

Chiral Magnetism And High-Temperature Skyrmions In B20-Ordered Co-Si, Balamurugan Balasubramanian, Priyanka Manchanda, Rabindra Pahari, Zhen Chen, Wenyong Zhang, Shah R. Valloppilly, Xingzhong Li, Anandakumar Sarella, Lanping Yue, Ahsan Ullah, Pratibha Dev, David A. Muller, Ralph Skomski, George C. Hadjipanayis, David J. Sellmyer

Nebraska Center for Materials and Nanoscience: Faculty Publications

Magnets with chiral crystal structures and helical spin structures have recently attracted much attention as potential spin-electronics materials, but their relatively low magnetic-ordering temperatures are a disadvantage. While cobalt has long been recognized as an element that promotes high-temperature magnetic ordering, most Co-rich alloys are achiral and exhibit collinear rather than helimagnetic order. Crystallographically, the B20-ordered compound CoSi is an exception due to its chiral structure, but it does not exhibit any kind of magnetic order. Here, we use nonequilibrium processing to produce B20-ordered Co_1+xSi_1−x with a maximum Co solubility of x = 0.043. Above a critical …

Effective Field Theory And Machine Learning Approaches To Controlling Nonperturbative Uncertainties In Flavor Physics, Ayesh Gunawardana

Wayne State University Dissertations

The radiative decay $\bar{B}\to X_s\gamma$ and semileptonic heavy meson decay $D\to \pi l \nu$ are important flavor physics probes of new physics. However, these decays are plagued with nonperturbative uncertainties that are needed to be controlled to obtain a theoretically clean description. In this dissertation, we provide effective field theory and machine learning approaches to controlling these uncertainties.\par

In $\bar B\to X_s\gamma$, the largest uncertainty on the total rate and the CP asymmetry arises from resolved photon contributions. These appear first at order $1/m_b$ and are related to operators other than $Q_{7\gamma}$ in the effective weak Hamiltonian. One of the …

Analysis Of Magnetization Directions Of Lunar Swirls, Lillie Cole

Lewis Honors College Capstone Collection

Lunar Swirls are high albedo markings on the Moon that exist in the regions of some crustal magnetic anomalies. The precise mechanism responsible for the swirl features is unknown but a prevailing theory is solar wind standoff, where the magnetic field from subsurface magnetized sources protects the lunar surface from solar wind ions, leading to their lesser maturation and brighter appearance. If this theory is correct, the magnetic field of the anomalies should heavily influence the appearance of the swirl. To better understand the cause of swirls, the magnetization direction of the source creating the field is analyzed. This study …

The Origins Of Phantom Partials In The Piano, Lauren M. Neldner

Honors Program Theses

Phantom partials are anomalous frequency components identifiable in the sound of the piano and occur at the sum and difference frequencies of two overtones. For several decades they have been identified as crucial components to the sound of the piano and assumed to be generated by the forced longitudinal motion of the string. Recent work has identified that contrary to common belief, most of the power is produced in the non-string components with the most likely source being the wooden structural components. This work presents experimental results for two plausible theories that could explain the origins of phantom partials in …

Rod-Shape Theranostic Nanoparticles Facilitate Antiretroviral Drug Biodistribution And Activity In Human Immunodeficiency Virus Susceptible Cells And Tissues, Bhavesh D. Kevadiya, Brendan Ottemann, Insiya Z. Mukadam, Laura Castellanos, Kristen Sikora, James R. Hilaire, Jatin Machhi, Jonathan Herskovitz, Dhruvkumar Soni, Mahmudul Hasan, Wenting Zhang, Anandakumar Sarella, Jered Garrison, Joellyn Mcmillan, Benson Edagwa, R. Lee Mosley, Richard W. Vachet, Howard E. Gendelman

Nebraska Center for Materials and Nanoscience: Faculty Publications

Human immunodeficiency virus theranostics facilitates the development of long acting (LA) antiretroviral drugs (ARVs) by defining drug-particle cell depots. Optimal drug formulations are made possible based on precise particle composition, structure, shape and size. Through the creation of rod-shaped particles of defined sizes reflective of native LA drugs, theranostic probes can be deployed to measure particle-cell and tissue biodistribution, antiretroviral activities and drug retention.

Methods: Herein, we created multimodal rilpivirine (RPV) ¹⁷⁷lutetium labeled bismuth sulfide nanorods (¹⁷⁷LuBSNRs) then evaluated their structure, morphology, configuration, chemical composition, biological responses and adverse reactions. Particle biodistribution was analyzed by single …

Svat4: A Computer Program For Visualization And Analysis Of Crystal Structures, Xingzhong Li

Nebraska Center for Materials and Nanoscience: Faculty Publications

SVAT4 is a computer program for interactive visualization of three-dimensional crystal structures, including chemical bonds and magnetic moments. A wide range of functions, e.g. revealing atomic layers and polyhedral clusters, are available for further structural analysis. Atomic sizes, colors, appearance, view directions and view modes (orthographic or perspective views) are adjustable. Customized work for the visualization and analysis can be saved and then reloaded. SVAT4 provides a template to simplify the process of preparation of a new data file. SVAT4 can generate high-quality images for publication and animations for presentations. The usability of SVAT4 is broadened by a software suite …

Quantifying Electron Precipitation In The Van Allen Radiation Belts, Timothy Raeder

Honors Theses and Capstones

The spatial and temporal distribution of high energy electron precipitation from the Van Allen radiation belts is not currently well-understood. The FIREBIRD-II mission (2015-present) and the Van Allen Probes (2012-2019) provide a unique opportunity to examine the behaviors and drivers of high energy electron precipitation. This study quantifies electron precipitation observed by FIREBIRD-II as a function of radial distance (L-shell), magnetic local time (MLT), hemisphere, and geomagnetic indices (Kp). Electron precipitation was observed to peak at L-shell 4.5-5. Regions of elevated electron precipitation were identified at L-shell 4-6 at dawn (MLT 6-9) and dusk (MLT 15-21). Hemisphere filtering indicated very …

Fostering Physics Content And Pedagogy Learning By Future Physics Teachers Via Student Authored Youtube Video Projects, David Abbott, Dan L. Macisaac, Brad Gearhart, Kathleen Falconer, Florian Genz, Andre Bresges, Stefan Hoffmann, Jeremias Weber

Videos for Physics Teaching

We describe a curricular innovation for STEM teacher preparation -- the use of video projects in undergraduate and graduate physics courses for future physics teachers at SUNY Buffalo State. US courses were adapted under the guidance of our colleagues’ similar work at Universität zu Köln [1]. Our students prepared end of course short “proof of concept” rough video vignettes of 5-10min addressing both physics content and physics pedagogical topics. YouTube [2] example videos are provided, and insights are shared.

Recent Developments In The Pyscf Program Package, Qiming Sun, Xing Zhang, Samragni Banerjee, Peng Bao, Marc Barbry, Nick S. Blunt, Nikolay A. Bogdanov, George H. Booth, Jia Chen, Zhi-Hao Cui, Janus J. Eriksen, Yang Gao, Sheng Gun, Jan Hermann, Matthew R. Hermes, Kevin Koh, Peter Koval, Susi Lehtola, Zhendong Li, Junzi Liu, Narbe Mardirossian, James D. Mcclain, Mario Motta, Bastien Mussard, Hung Q. Pham, Artem Pulkin, Wirawan Purwanto, Paul J. Robinson, Enrico Ronca, Elvira R. Sayfutyarova, Maximillian Scheurer, Henry F. Schurkus, James E.T. Smith, Chong Sun, Shi-Ning Sun, Shiv Upadhyay, Lucas K. Wagner, Xiao Wang, Alec White, James Daniel Whitfield, Mark J. Williamson, Sebastian Wouters, Jun Yang, Jason M. Yu, Tianyu Zhu, Timothy C. Berkelbach, Sandeep Sharma, Alexander Yu Sokolov, Garnet Kin-Lic Chan

University Administration Publications

PySCF is a Python-based general-purpose electronic structure platform that supports first-principles simulations of molecules and solids as well as accelerates the development of new methodology and complex computational workflows. This paper explains the design and philosophy behind PySCF that enables it to meet these twin objectives. With several case studies, we show how users can easily implement their own methods using PySCF as a development environment. We then summarize the capabilities of PySCF for molecular and solid-state simulations. Finally, we describe the growing ecosystem of projects that use PySCF across the domains of quantum chemistry, materials science, machine learning, and …

Electrodynamics Modeling Of Plasmonic-Organic Hybrid Waveguides, Marcus Michel

Pomona Senior Theses

Optical fibers have multiple advantages over conventional electrical connections, such as lower energy losses and higher bandwidth. To use optics for chip-to-chip communication, electro-optic (EO) modulators need to be scaled down to be incorporated on integrated circuits. This size reduction has been accomplished using plasmonic-organic hybrid (POH) waveguides, which make use of nonlinear organic EO materials and surface plasmon polaritons to achieve light modulation in devices with lengths on the micron scale. As these devices are just starting to be developed, there are many avenues for their potential optimization. In order to streamline and reduce the cost of the optimization …

A Review On Superluminal Physics And Superluminal Communication In Light Of The Neutrosophic Logic Perspective, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In a recent paper, we describe a model of quantum communication based on combining consciousness experiment and entanglement, which can serve as impetus to stop 5G-network-caused diseases. Therefore, in this paper we consider superluminal physics and superluminal communication as a bridge or intermediate way between subluminal physics and action-at-a-distance (AAAD) physics, especially from neutrosophic logic perspective. Although several ways have been proposed to bring such a superluminal communication into reality, such as Telluric wave or Telepathy analog of Horejev and Baburin, here we also review two possibilities: quaternion communication and also quantum communication based on quantum noise. Further research is …