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Anomalous Behavior in the Rotational Spectra of the v₈=2 and the v₈=3 Vibrations for the ¹³C and ¹⁵N Tagged Isotopes of the CH₃CN Molecule in the Frequency Range 17-95 GHz

Description: The rotational microwave spectra of the three isotopes (^13CH_3^12C^15N, ^12CH_3^13C^15N, and ^13CH_3^13C^15N) of the methyl cyanide molecule in the v_8=3, v_8=2, v_7=1 and v_4=1 vibrational energy levels for the rotational components 1£J£5 (for a range of frequency 17-95 GHz.) were experimentally and theoretically examined. Rotational components in each vibration were measured to determine the mutual interactions in each vibration between any of the vibrational levels investigated. The method … more
Date: December 1990
Creator: Al-Share, Mohammad A. (Mohammad Abdel)
open access

Application of Statistical Physics in Human Physiology: Heart-Brain Dynamics

Description: This dissertation is devoted to study of complex systems in human physiology particularly heartbeats and brain dynamics. We have studied the dynamics of heartbeats that has been a subject of investigation of two independent groups. The first group emphasized the multifractal nature of the heartbeat dynamics of healthy subjects, whereas the second group had established a close connection between healthy subjects and the occurrence of crucial events. We have analyzed the same set of data and esta… more
Date: August 2018
Creator: Bohara, Gyanendra
open access

Application of the Wigner Formalism to a Slightly Relativistic Quantum Plasma

Description: A slightly relativistic fermion gas is described by the dynamical theory obtained from the Wigner distribution function. The problem is approached in a self-consistent manner including the two-body Darwin Hamiltonian. The goal is to find the departures from equilibrium and dispersion relations for wave propagation in the gas.
Date: August 1967
Creator: Harper, John H.
open access

Artificially Structured Boundary for Control and Confinement of Beams and Plasmas

Description: An artificially structured boundary (ASB) produces a short-range, static electromagnetic field that can reflect charged particles. In the work presented, an ASB is considered to consist of a spatially periodic arrangement of electrostatically plugged magnetic cusps. When used to create an enclosed volume, an ASB may confine a non-neutral plasma that is effectively free of applied electromagnetic fields, provided the spatial period of the ASB-applied field is much smaller than any one dimension … more
Date: May 2018
Creator: Hedlof, Ryan
open access

Automatic Frequency Control of Microwave Radiation Sources

Description: Resonant cavity controlled klystron frequency stabilization circuits and quartz-crystal oscillator frequency stabilization circuits were investigated for reflex klystrons operating at frequencies in the X-band range. The crystal oscillator circuit employed achieved better than 2 parts in 10 in frequency stability. A test of the functional properties of the frequency standard was made using the Stark effect in molecules.
Date: August 1979
Creator: Payne, Bobby D.
open access

Band Theory and Beyond: Applications of Quantum Algorithms for Quantum Chemistry

Description: In the past two decades, myriad algorithms to elucidate the characteristics and dynamics of molecular systems have been developed for quantum computers. In this dissertation, we explore how these algorithms can be adapted to other fields, both to closely related subjects such as materials science, and more surprising subjects such as information theory. Special emphasis is placed on the Variational Quantum Eigensolver algorithm adapted to solve band structures of a periodic system; three distin… more
Date: May 2022
Creator: Sherbert, Kyle Matthew
open access

Broad-band Light Emission From Ion Implanted Silicon Nanocrystals Via Plasmonic and Non-plasmonic Effects for Optoelectronics

Description: Broad band light emission ranging from the ultraviolet (UV) to the near infrared (NIR) has been observed from silicon nanoparticles fabricated using low energy (30-45 keV) metal and non-metal ion implantation with a fluence of 5*1015 ions/cm2 in crystalline Si(100). It is found from a systematic study of the annealing carried out at certain temperatures that the spectral characteristics remains unchanged except for the enhancement of light emission intensity due to annealing. The annealing resu… more
Date: December 2012
Creator: Singh, Akhilesh K.
open access

A Calculation of the Excitation Spectrum of Superfluid Helium-4

Description: The Hartree-Fock-Bogoliubov theory of homogeneous boson systems at finite temperatures is rederived using, a free energy variational principle. It is shown that a t-matrix naturally emerges in the theory. Phenomenological modifications are made (1) to remove the energy gap at zero momentum, and (2) to eliminate the Hartree-Fock-like terms, which dress the kinetic energy of the particle. A numerical calculation of the energy spectrum is made over a temperature range of 0.00 to 3.14 K using the M… more
Date: May 1974
Creator: Goble, Gerald W.
open access

A Calculation of the Kaon-Neutron Scattering Cross Section

Description: The purpose of this investigation was to study the scattering processes of K+ mesons with neutrons. In order to do such a study one must first make certain basic assumptions about the type of interaction involved and then proceed to calculate physically meaningful qualities which describe the processes. Thus, the problem is this: assuming the validity of Feynman's rules for these strongly interacting particles, calculate the differential and total scattering cross sections for the interaction o… more
Date: June 1966
Creator: Hooper, Robert Gibson
open access

Carbon K-Shell X-Ray and Auger-Electron Cross Sections and Fluorescence Yields for Selected Molecular Gases by 0.6 To 2 .0 MeV Proton Impact

Description: Absolute K-shell x-ray cross sections and Auger-electron cross sections are measured for carbon for 0.6 to 2.0 MeV proton incident on CH₄, n-C₄H₁₀ (n-Butane), i-C₄H₁₀ (isobutane), C₆H₆ (Benzene), C₂H₂ (Acetylene), CO and CO₂. Carbon K-shell fluorescence yields are calculated from the measurements of x-ray and Auger-electron cross sections. X-ray cross sections are measured using a variable geometry end window proportional counter. An alternate method is described for the measurement of the tran… more
Date: August 1986
Creator: Bhalla, Raj P. (Raj Pal), 1948

Carbon Nanotube/Microwave Interactions and Applications to Hydrogen Fuel Cells.

Description: One of the leading problems that will be carried into the 21st century is that of alternative fuels to get our planet away from the consumption of fossil fuels. There has been a growing interest in the use of nanotechnology to somehow aid in this progression. There are several unanswered questions in how to do this. It is known that carbon nanotubes will store hydrogen but it is unclear how to increase that storage capacity and how to remove this hydrogen fuel once stored. This document off… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2004
Creator: Imholt, Timothy James
open access

Chaos and Momentum Diffusion of the Classical and Quantum Kicked Rotor

Description: The de Broglie-Bohm (BB) approach to quantum mechanics gives trajectories similar to classical trajectories except that they are also determined by a quantum potential. The quantum potential is a "fictitious potential" in the sense that it is part of the quantum kinetic energy. We use quantum trajectories to treat quantum chaos in a manner similar to classical chaos. For the kicked rotor, which is a bounded system, we use the Benettin et al. method to calculate both classical and quantum Lyapun… more
Date: August 2005
Creator: Zheng, Yindong

Characterization, Properties and Applications of Novel Nanostructured Hydrogels.

Description: The characterization, properties and applications of the novel nanostructured microgel (nanoparticle network and microgel crystal) composed of poly-N-isopropylacrylanmide-co-allylamine (PNIPAM-co-allylamine) and PNIPAM-co-acrylic acid(AA) have been investigated. For the novel nanostructured hydrogels with the two levels of structure: the primary network inside each individual particle and the secondary network of the crosslinked nanoparticles, the new shear modulus, drug release law from hydrog… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: December 2006
Creator: Tang, Shijun
open access

Charge Collection Studies on Integrated Circuit Test Structures using Heavy-Ion Microbeams and MEDICI Simulation Calculations

Description: Ion induced charge collection dynamics within Integrated Circuits (ICs) is important due to the presence of ionizing radiation in the IC environment. As the charge signals defining data states are reduced by voltage and area scaling, the semiconductor device will naturally have a higher susceptibility to ionizing radiation induced effects. The ionizing radiation can lead to the undesired generation and migration of charge within an IC. This can alter, for example, the memory state of a bit, and… more
Date: May 2000
Creator: Guo, Baonian
open access

Charge State Dependence of L-Shell X-Ray Production Cross Sections of ₂₈Ni, ₂₉Cu, ₃₀Zn, ₃₁Ga, and ₃₂Ge by Energetic Oxygen Ions

Description: Charge state dependence of L-shell x-ray production cross sections have been measured for 4-14 MeV ¹⁶O^q (q=3⁺-8⁺) ions incident on ultra-clean, ultra-thin copper, and for 12 MeV ¹⁶O^q (q=3⁺-8⁺) on nickel, zinc, gallium and germanium solid foils. L-shell x-ray production cross section were measured using target foils of thickness ≤0.6 μg/cm² evaporated onto 5 μg/cm² carbon backings. Oxygen ions at MeV energies and charge state q were produced using a 3MV 9SDH-2 National Electrostatics Corporati… more
Date: August 1996
Creator: Azordegan, Amir R. (Amir Reza)
open access

Charge State Dependence of M-Shell X-Ray Production in 67Ho by 2-12 MeV Carbon Ions

Description: The charge state dependence of M-shell x-ray production cross sections of 67HO bombarded by 2-12 MeV carbon ions with and without K-vacancies are reported. The experiment was performed using an NEC 9SDH-2 tandem accelerator at the Ion Beam Modification and Analysis Laboratory of the University of North Texas. The high charge state carbon ions were produced by a post-accelerator stripping gas cell. Ultra-clean holmium targets were used in ion-atom collision to generate M-shell x rays at energies… more
Date: August 1994
Creator: Sun, Hsueh-Li
open access

Charged Particle Transport and Confinement Along Null Magnetic Curves and in Various Other Nonuniform Field Configurations for Applications in Antihydrogen Production

Description: Comparisons between measurements of the ground-state hyperfine structure and gravitational acceleration of hydrogen and antihydrogen could provide a test of fundamental physical theories such as CPT (charge conjugation, parity, time-reversal) and gravitational symmetries. Currently, antihydrogen traps are based on Malmberg-Penning traps. The number of antiprotons in Malmberg-Penning traps with sufficiently low energy to be suitable for trappable antihydrogen production may be reduced by the el… more
Date: May 2016
Creator: Lane, Ryan A.
open access

Chlorine Nuclear Quadrupole Resonance Absorption of 3, 4, 5, 6 - Tetrachlorophthalimide and 1, 3, 6, 8 - Tetrachloropyrene

Description: In this study frequency modulation was used with a regenerative spectrometer and a super-regenerative spectrometer to detect the nuclear quadrupole resonance frequencies of chlorine in two commercially available compounds, 1, 3, 6, 8 - tetrachlorophyrene and 3, 4, 5, 6 - tetrachlorophthalimide.
Date: January 1968
Creator: Reeves, Jerry Byron
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