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Full-Text Articles in Physical Sciences and Mathematics

Mc-Pdft Can Calculate Singlet-Triplet Splittings Of Organic Diradicals., Samuel J. Stoneburner, Donald G. Truhlar, Laura Gagliardi Jan 2018

Mc-Pdft Can Calculate Singlet-Triplet Splittings Of Organic Diradicals., Samuel J. Stoneburner, Donald G. Truhlar, Laura Gagliardi

Educator Scholarship

The singlet-triplet splittings of a set of diradical organic molecules are calculated using multiconfiguration pair-density functional theory (MC-PDFT) and the results are compared with those obtained by Kohn-Sham density functional theory (KS-DFT) and complete active space second-order perturbation theory (CASPT2) calculations. We found that MC-PDFT, even with small and systematically defined active spaces, is competitive in accuracy with CASPT2, and it yields results with greater accuracy and precision than Kohn-Sham DFT with the same parent functional. MC-PDFT also avoids the challenges associated with spin contamination in KS-DFT. It is also shown that MC-PDFT is much less computationally expensive than CASPT2 …


Applied Temperament, Geoffrey D. Hershberger Jan 2018

Applied Temperament, Geoffrey D. Hershberger

Theses and Dissertations--Music

The following document was created in order to promote intonation consensus in ensembles and to better facilitate learning in educational settings. Non-keyboard instruments provide musicians an opportunity to make nearly infinitesimal adjustments to pitch while performing; this creates difficulties for students and challenges even the most seasoned professionals. Non-keyboard musicians struggle their whole lives to play in tune, and even when one knows exactly where they want to place a pitch, technical difficulties can foul any musician's performance. When performing solo, the musician must choose a tuning system that is suitable for the music being performed, and attempt to realize …


Two Stream Instability In Graphene, Mitchell Duffer Jan 2018

Two Stream Instability In Graphene, Mitchell Duffer

Williams Honors College, Honors Research Projects

Mitchell Duffer

Major: Physics

Project Sponsor: Ben Yu-Kuang Hu

Number of Project Credits: 2

Two Stream Instability in Graphene

We investigate the unstable modes of the two-stream instability in graphene to determine if they can occur. This instability occurs when a population of electrons streams past another inside graphene. We obtain the unstable modes by numerically determining the zeros of the non-equilibrium graphene dielectric function using MATLAB. The dielectric function used in this study, in contrast to previous studies, includes the effects of the particle-hole excitation continuum (PHEC) that normally quells the evolution of unstable plasmons. MATLAB’s built in zero …


Examining The Response Of The Martian Atmosphere To Increases In Different Portions Of The Electromagnetic Spectrum During Solar Flares, Bradley R. Kumm Jan 2018

Examining The Response Of The Martian Atmosphere To Increases In Different Portions Of The Electromagnetic Spectrum During Solar Flares, Bradley R. Kumm

Master's Theses and Doctoral Dissertations

This report describes the methods used to examine how the Martian atmosphere responds to increases in different portions of the electromagnetic spectrum during solar flares. On March 24, 2015 the Mars Atmosphere and Volatile Evolution (MAVEN) mission satellite made measurements of the atmosphere and solar irradiance during a solar flare. These measurements were used by the Flare Irradiance Spectral Model (FISM) to generate solar flux values for 59 wavelength bins describing flare event. The solar flux values at different wavelength bins were scaled by different amounts and input into the Mars Global Ionosphere Thermosphere Model (M-GITM) to create 16 distinct …


A Comparison Of Online, Video Synchronous, And Traditional Learning Modes For An Introductory Undergraduate Physics Course, Emily K. Faulconer, John C. Griffith, Beverly Wood, Donna Roberts Jan 2018

A Comparison Of Online, Video Synchronous, And Traditional Learning Modes For An Introductory Undergraduate Physics Course, Emily K. Faulconer, John C. Griffith, Beverly Wood, Donna Roberts

Publications

While the equivalence between online and traditional classrooms has been well-researched, very little of this includes college-level introductory Physics. Only one study explored Physics at the whole-class level rather than specific course components such as a single lab or a homework platform. In this work, we compared the failure rate, grade distribution, and withdrawal rates in an introductory undergraduate Physics course across several learning modes including traditional face-to-face instruction, synchronous video instruction, and online classes. Statistically significant differences were found for student failure rates,grade distribution, and withdrawal rates but yielded small effect sizes. Post-hoc pair-wise test was run to determine …


Understanding, Designing And Building A Hydroelectric Generator, Nicholas Weare Shenberger Jan 2018

Understanding, Designing And Building A Hydroelectric Generator, Nicholas Weare Shenberger

Senior Projects Spring 2018

When you hear the word hydropower you automatically jump to using water in order to create power or electricity. However, delving deeper and trying to understand the technology involved in it becomes quite a lot more complicated. To try to comprehend some of the knowledge of how to convert the power of water into electricity, I decided to design and build my own hydroelectric generator. I took the time to research and discover more about the process of building a generator and the specific pieces that come together in order to build one specifically powered by water. After my research, …


Establishing A Quality Assurance Routine For Digital Imaging, Sulaiman Rana Al Jan 2018

Establishing A Quality Assurance Routine For Digital Imaging, Sulaiman Rana Al

Browse all Theses and Dissertations

In the clinical medical physics field, Quality Assurance (QA) is a fundamental topic to insure patient safety and effective treatment. In recent years, the imaging hardware for diagnostic x-rays has been shifting to fully digital detectors. However, the quality assurance tests for such detectors in the clinical setting is still under development. In the Medical Imaging Department of Kettering Hospital (Kettering, OH), the currently accepted method of performing QA on detectors is to use an extensive set of tests suggested by the manufacturer. This set of tests requires about 90 minutes, which is too long for daily use. The goal …


The Encyclopedia Of Neutrosophic Researchers - Vol. 2, Florentin Smarandache Jan 2018

The Encyclopedia Of Neutrosophic Researchers - Vol. 2, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

This is the second volume of the Encyclopedia of Neutrosophic Researchers, edited from materials offered by the authors who responded to my invitation. The introduction contains a short history of neutrosophics, together with links to the main papers and books. The authors who have published neutrosophic papers, books, or defended neutrosophic master theses or PhD dissertations and are not included in the two ENR volumes, are kindly invited to send their self-presentations or their CVs, a photo, and a list of neutrosophic publications to smarand@unm.edu and neutrosophy@laposte.net to be part of a third volume.

Florentin Smarandache


Quantifying Effects Of Using Thermally Thin Fuel Approximations On Modelling Fire Propagation In Woody Fuels, David Blasen, Jesse Johnson, William Jolly, Russell Parsons Jan 2018

Quantifying Effects Of Using Thermally Thin Fuel Approximations On Modelling Fire Propagation In Woody Fuels, David Blasen, Jesse Johnson, William Jolly, Russell Parsons

Graduate Student Theses, Dissertations, & Professional Papers

In this paper, we quantify the effects of the thermally thin fuel approximations commonly made in numerical models that eliminate temperature gradients within a heated object. This assumption is known to affect the modeled ignition and burn behavior, but there is little research on its impact, particularly in larger fuels or in numerical models including moisture and chemical decomposition of fuels.

We begin by comparing modeled to observed ignition times and burn rates. To constrain variability in the material properties of wood and focus on variability caused by fuels assumed to be thermally thin, we conduct experiments using thermogravimetric analysis …


Underwater Acoustic Signal Analysis Toolkit, Kirk Bienvenu Jr Dec 2017

Underwater Acoustic Signal Analysis Toolkit, Kirk Bienvenu Jr

University of New Orleans Theses and Dissertations

This project started early in the summer of 2016 when it became evident there was a need for an effective and efficient signal analysis toolkit for the Littoral Acoustic Demonstration Center Gulf Ecological Monitoring and Modeling (LADC-GEMM) Research Consortium. LADC-GEMM collected underwater acoustic data in the northern Gulf of Mexico during the summer of 2015 using Environmental Acoustic Recording Systems (EARS) buoys. Much of the visualization of data was handled through short scripts and executed through terminal commands, each time requiring the data to be loaded into memory and parameters to be fed through arguments. The vision was to develop …


Muon-Neutrino Electron Elastic Scattering And A Search For The Muon-Neutrino Magnetic Moment In The Nova Near Detector, Biao Wang Dec 2017

Muon-Neutrino Electron Elastic Scattering And A Search For The Muon-Neutrino Magnetic Moment In The Nova Near Detector, Biao Wang

Physics Theses and Dissertations

We use the NOvA near detector and the NuMI beam at Fermilab to study the neutrino-electron elastic scattering and the muon neutrino magnetic process beyond the Standard Model physics. The particle identifications of neutrino on electron elastic scattering are trained by using the multi-layer neural networks. This thesis provides a general discussion of this technique and shows a good agreement between data and MC for the neutrino-electron elastic weak scattering. By using 3.62e20 POT dataset in the NOvA near detector, we find 1.58e-9 Bohr magneton as the 90% C.L. upper limit. We also find a sensitivity of 8e-10 Bohr magneton …


Phys 211: Mechanics, Gravitation, And Waves, Ilya Kravchenko Oct 2017

Phys 211: Mechanics, Gravitation, And Waves, Ilya Kravchenko

Department of Physics and Astronomy: Syllabi

Syllabus for PHYS 211: Mechanics, Gravitation, and Waves syllabus for Fall 2017 semester.


College Of Science And Mathematics Newsletter, Fall 2017, College Of Science And Mathematics, Wright State University Oct 2017

College Of Science And Mathematics Newsletter, Fall 2017, College Of Science And Mathematics, Wright State University

College of Science and Mathematics Newsletters

This 6 page newsletter discusses various happenings within the College of Science and Mathematics. It begins with a letter from the dean, and continues on with news, events, alumni news, and other community news.


Phys 201: Modern Topics In Physics And Astronomy, Ken Bloom Oct 2017

Phys 201: Modern Topics In Physics And Astronomy, Ken Bloom

Department of Physics and Astronomy: Syllabi

Syllabus for PHYS 201: Modern Topics in Physics and Astronomy syllabus for Fall 2017.


Nuclear Magnetic Resonance Studies Of Electrode And Electrolyte Materials For Li-Ion Batteries, Lisa Cirrincione Sep 2017

Nuclear Magnetic Resonance Studies Of Electrode And Electrolyte Materials For Li-Ion Batteries, Lisa Cirrincione

Dissertations, Theses, and Capstone Projects

In this thesis, Nuclear Magnetic Resonance (NMR) spectroscopic techniques are used to study lithium electrode and electrolyte materials for advanced rechargeable lithium ion batteries. Three projects are described in this thesis. The first involves 23Na and 37Al static and magic angle spinning NMR studies of NaAlH4/C anode materials for advanced rechargeable batteries. The second project is a study of paramagnetic lithium transition-metal phosphate cathode materials for Li-ion batteries, where 7Li, and 31P single crystal NMR was used in order to obtain detailed information on the local electronic and magnetic environments. The third project investigates …


Designing A Microfluidic Sorting Network With Heat Treated Plastic, Houghton Yonge '18, Fuming Qui '19, Viva R. Horowitz Aug 2017

Designing A Microfluidic Sorting Network With Heat Treated Plastic, Houghton Yonge '18, Fuming Qui '19, Viva R. Horowitz

Posters

A microfluidic device is necessary to sort nanodiamonds based on their luminescence. We explored utilizing the repeatable shrinkage of heat treated Shrinky Dink (polystyrene) sheets in an effort to find an easier, cheaper alternative to the traditional photolithography process. Our work found encouraging results but the plastic’s capabilities must be further studied to decisively determine its usefulness.


Foundations, 3, David Peak Aug 2017

Foundations, 3, David Peak

Foundations

Our goal is to try to reconcile classical EM with the existence of photons. The electric and magnetic fields associated with EM radiation, propagating in the x -direction, obey the Maxwell wave equation: ∂2E/∂t2 = c2(∂2E/∂x2).


Foundations, 1, David Peak Aug 2017

Foundations, 1, David Peak

Foundations

Quantum mechanics is money

Text message and take a picture with your smart phone; watch a movie on your Blu-ray player; get the bar code on your bag of chips scanned; obtain an MRI image of your aching shoulder; take a ride on a maglev train. None of these—and countless other—things would be possible without quantum mechanics! Leon Lederman, Nobel Prize winning physicist, is widely quoted as saying that 1/3 of the world’s economy is due to quantum mechanics. Lederman’s estimate is actually probably too low, but what surely is the case is that computers, lasers, and superconducting magnets (to …


Many-Particle Systems, 9, David Peak Aug 2017

Many-Particle Systems, 9, David Peak

Many Particles

Superconductivity phenomenology

Superconductors are materials that exhibit zero (or close to zero) resistance to electrical currents as well as perfect diamagnetism (the Meissner Effect). When a current is started in a superconducting loop, it persists for a very long time without an applied potential difference. The resistivity of a superconductor is measured to be less than 4x10–25 Ω-m (for comparison, the resistivity of an ordinary good conductor is about 10–8 Ω-m), and the associated decay time for the current is estimated to be greater than 100,000 years (as opposed to about 1 µs for an ordinary good …


Many-Particle Systems, 7, David Peak Aug 2017

Many-Particle Systems, 7, David Peak

Many Particles

Electronic energy bands in crystalline solids: The finite well model

Previously, we have considered the “conduction electrons” in a metal as if they were an ideal gas in a 3D infinite well. What allows us to do that? A crystalline solid consists of a periodic array of atoms, packed so close to one another that “flow” (long range relative motion of groups of atoms) is essentially impossible. It is useful to think of a solid as a giant (rigid) molecule. The periodic structure of the atoms has profound consequences for the behavior of the solid’s electrons. While, in detail, the …


Many-Particle Systems, 2, David Peak Aug 2017

Many-Particle Systems, 2, David Peak

Many Particles

Multi-electron atoms

The rich diversity of chemical processes and structures is directly related to the diversity of electronic states of multi-electron atoms that, in turn, is dictated by the Pauli Exclusion Principle. To see how the Pauli Exclusion Principle produces atomic diversity, it is useful to begin simply, in particular, by considering the most elementary multi-electron “atom”: the hydrogen anion, H.


Many-Particle Systems, 3, David Peak Aug 2017

Many-Particle Systems, 3, David Peak

Many Particles

Bare essentials of statistical mechanics

Atoms are examples of many-particle systems, but atoms are extraordinarily simpler than macroscopic systems consisting of 1020-1030 atoms. Despite their great size, many properties of macroscopic systems depend intimately on the microscopic behavior of their microscopic constituents. The proper quantum mechanical description of an N -particle system is a wavefunction that depends on 3N coordinates (3 ways of moving, in general, for every particle) and 4N quantum numbers (3 motional quantum numbers and 1 spin quantum number for every particle). (If the “particles” are molecules there might be additional quantum …


Many-Particle Systems, 5, David Peak Aug 2017

Many-Particle Systems, 5, David Peak

Many Particles

Photons as T → 0 K

Photons are massless bosons. Because they are massless, any number of them can be added or subtracted without changing the photon system energy. (For example, a 1 eV photon can be exchanged for one hundred 0.01 eV photons, without changing system energy.) As a result, the chemical potential for photons is zero.


Many-Particle Systems, 11, David Peak Aug 2017

Many-Particle Systems, 11, David Peak

Many Particles

Quantum information

In Mn10 we discussed the rudiments of “classical computation.” Classical, conventional computation involves combinations of transistors that convert low- and high-voltage inputs into different low- and high-voltage outputs. These voltages are interpreted as the binary digits 0 and 1, i.e., as bits. How bits are changed into other bits leads to such things as text preparation and storage, numerical calculations and symbolic manipulations, image and sound generation, game playing, intercontinental communication—in short, the modern world of information.


Many-Particle Systems, 4, David Peak Aug 2017

Many-Particle Systems, 4, David Peak

Many Particles

Absolute temperature

When a system is in statistical equilibrium it can usefully be characterized by a few macroscopic variables. Temperature is one of the most important of these. The absolute temperature scale (measured in kelvins, K) has the following properties. (1) T = 0 K is the temperature of a macroscopic system found permanently in its ground state. Such a system has no excitations; it has its lowest possible energy and is completely isolated from the rest of the universe.


Many-Particle Systems, 1, David Peak Aug 2017

Many-Particle Systems, 1, David Peak

Many Particles

Wavefunctions for more than one particle: Different kinds of particles

Introductory examples of quantum mechanical wavefunction calculations involve a single particle moving about in a “magic” potential energy—e.g., a particle trapped inside a square well or an electron in a hydrogen atom. But, potential energy arises from interaction, so these situations must inevitably include more than one particle. Even the simplest atom—hydrogen— consists of two particles: the electron and the proton. So, how should the Schrödinger Equation be generalized to account for multiple particles?


Many-Particle Systems, 8, David Peak Aug 2017

Many-Particle Systems, 8, David Peak

Many Particles

The classical picture of how electrons migrate through a resistor driven by an applied potential difference draws an analogy with a kind of pinball machine. In a pinball machine, gravity accelerates the pinball down the table, but the ball’s progress is impeded by collisions with bumpers, as depicted to the right. (θ is the angle the table makes with the horizontal direction.) When averaged over many collisions the ball’s average equation of motion is ma = mg sinθ − mv/τ , where a and v are directed down the table, and τ is the average time between collisions. If the …


Problem Set #10, David Peak Aug 2017

Problem Set #10, David Peak

Problems

Blackbody


Problem Set #4, David Peak Aug 2017

Problem Set #4, David Peak

Problems

Some 1D infinite well stuff


Problem Set #12, David Peak Aug 2017

Problem Set #12, David Peak

Problems

Solid stuff