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A Lagrangian For A System Of Two Dyons, Rainer Georg Thierauf

Dissertations and Theses

Maxwell's equations for the electromagnetic field are symmetrized by introducing magnetic charges into the formalism of electrodynamics. The symmetrized equations are solved for the fields and potentials of point particles. Those potentials, some of which are found to be singular along a line, are used to formulate the Lagrangian for a system of two dyons (particles with both electric and magnetic charge). The equations of motion are derived from the Lagrangian. It is shown that the dimensionality constants k and k*, which were introduced to define the units of the electromagnetic fields, have to be equal in order to avoid …

Division-Of-Wave-Front Thin-Film Beam Splitter For Generating Binary Patterns Of Orthogonal Elliptical Polarization States, R. M.A. Azzam

Electrical Engineering Faculty Publications

A division-of-wave-front thin-film beam splitter is described that reflects monochromatic light at oblique incidence with orthogonal elliptical polarization states. It consists of a metallic substrate partially covered with a transparent thin film that inverts the ratio ρ of the complex p and s reflection coefficients at the principal angle of the metal. Any pattern of coated and uncoated areas of the substrate is imprinted upon the reflected wave front as a corresponding two-dimensional spatial binary polarization pattern. A specific design is given that uses a Au substrate at a wavelength of 632.8 nm. The effects of small errors in the …

Thin-Film Devices For Polarized Light- Introduction, R. M.A. Azzam, William H. Southwell

Electrical Engineering Faculty Publications

No abstract provided.

The Effects Of Low Doses (1 To 500 Kilograys) Of 100-Kev Electrons On Four Polymers, Cynthia Anne Bradbury

Physics Theses & Dissertations

Commercial films of polyetherimide (PEI), polyetheretherimide (PEEI), polyethylene terephthalate (PET), and polycarbonate (PC) were exposed in vacuum to l 00-keV electron radiation to total absorbed doses of l, l 0, l 00, 300, and 500 kilograys. The concentration of radiation-generated radicals, as measured by electron paramagnetic resonance (EPR), increased by over an order of magnitude in all four polymers. Correspondingly, the intensity of the infrared absorption peaks increased uniformly for all doses. Solubility tests resulted in decreased solubility in all polymers. IR, EPR, and solubility suggest dehydrogenation of the aliphatic C-H and phenyl C-H sites. The data indicated that cross …

Extrema Of The Magnitude And The Phase Of A Complex Function Of A Real Variable: Application To Attenuated Internal Reflection, R. M.A. Azzam

Electrical Engineering Faculty Publications

Given a complex function F(ω) = |F(ω)|exp[jΔ(ω)] of a real argument ω, the extrema of its magnitude |F(ω)| and its phase Δ(ω), as functions of ω, are determined simultaneously by finding the roots of one common equation, Im[G(ω)] = 0, where G= (F′/F)² and F′ = ∂F/∂ω. The extrema of |F| and Δ are associated with Re G < 0 and Re G > 0, respectively. This easy-to-prove theorem has a wide range of applications in physical optics. We consider attenuated internal reflection (AIR) as …

30th Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and abstracts from the 30th annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, July 31 - August 5, 1988.

Calculations Of Three-Dimensional Transonic Flows Using The Implicit Formulation Of The Isenthalpic Euler Equations With Flux Vector Splitting, Frank E. Cannizzaro

Mechanical & Aerospace Engineering Theses & Dissertations

A numerical method for solving three-dimensional transonic flows using the isenthalpic formulation of the Euler equations is developed. The method uses van Leer's flux vector splitting to solve the implicit formulation of the governing equations, which are applied to a cell centered finite-volume scheme. A three factor spatial approximate factorization is implemented in solving the implicit part of the governing equations. Time marching to a steady state solution requires short computational times due to the relative efficiency of the basic method. Computational times are further reduced by the implementation of the multigrid acceleration technique, which provided converged solutions in approximately …

The Relationship Of Pore Volume And Pore Size Distribution To The Development Of Gloss And Scattering Coefficient, John A. Cook

Masters Theses

This study describes in a quantitative manner the relationships between coating structure and optical properties. Gloss, scattering coefficient and void volume were measured after applying different blends of polystyrene spheres to mylar film. Each coating was modeled using large spherical particles of the same size ratios to measure pore size distribution. The coating structure followed well with theoretical packing characteristics of spheres. Optical properties were related to changes in coating structure. Scattering coefficient and gloss correlated better with pore size distribution than particle size. Gloss increased when total void volume was reduced, while the scattering coefficient decreased.

Ferroelectric Nematic Liquid Crystals: Realizability And Molecular Constraints, Rolfe G. Petschek

Faculty Scholarship

There is no fundamental reason that fluids should not be ferroelectric. However, the only knownferroelectric fluids are chiral smectic-C liquid crystals and related structures. We examine the possibility that molecules with permanent dipole moments can form a ferroelectric nematic phase, the least ordered conceivable ferroelectric phase. We show that reasonable electric dipole interactions between diskshaped molecules may lead to such a phase, and calculate the phase diagram using mean-field theory. Some constraints on the constituent molecules are discussed.

Thermodynamics Analysis Of Refrigeration, Joe Lam

Undergraduate Honors Capstone Projects

In this term paper, I will look indepth at refrigeration. Refrigeration is a rather long and complex topic. Therefore, I will only discuss it as detail as conditions permit. As for the parts where minute details required, I will refer you to the selected references. In discussing refrigeration, I will first look at the Carnot cycle as a fundamental issue for refrigeration.

General Analysis And Optimization Of The Four-Detector Photopolarimeter, R. M.A. Azzam, I. M. Elminyawi, A. M. El-Saba

Electrical Engineering Faculty Publications

The four-detector photopolarimeter (FDP) is analyzed for an arbitrary spatial configuration and any reflection characteristics (r_i, ψ_i, Δ_i) of the first three detectors. The instrument matrix A, which relates the output signal vector I to the input Stokes vector S by I = AS, and its determinant are derived explicitly. The essential condition that A be nonsingular (det A ≠ 0) is satisfied in general with uncoated absorbing detector surfaces, assuming that the plane of incidence (POI) is rotated between successive reflections by other than 90°. Therefore no special coatings on …

Modal Interference Techniques For Strain Detection In Few-Mode Optical Fibers, Bradley D. Duncan

Electro-Optics and Photonics Faculty Publications

Interference between the modes of an optical fiber results in specific intensity patterns which can be modulated as a function of disturbances in the optical fiber system. These modulation effects are a direct result of the difference in propagation constants of the constituent modes. In this presentation it is shown how the modulated intensity patterns created by the interference of specific mode groups in few-mode optical fibers (V < 5.0) can be used to detect strain. A detailed discussion of the modal phenomena responsible for the observed strain induced pattern modulation is given and it is shown that strain detection sensitivities on the order of 10-9 can be expected. Data taken during the evaluation of an actual experimental strain detection system based on the developed theory is also presented.

Self Consistent Model Of The Glow Discharge, Hao Chen

Electrical & Computer Engineering Theses & Dissertations

The strong spatial variation of the electric field intensity in the vicinity of the cathode of a gas discharge requires the use of microscopic methods to describe the nonequilibrium behavior of the electron dynamics in this region. A one-dimensional Monte Carlo code was developed. It allows one to obtain the distribution of the electron drift velocity and rate coefficients for a given electric field intensity in the cathode fall. The results of this calculation are used to find the density distribution of charged particles in this region and consequently, by means of Poisson's equation, a corrected electric field intensity. In …

Observations Of Auroral E Region Plasma Waves And Electron Heating Witheiscat And A Vhf Radar Interferometer, J. Providakes, D. T. Farley, B. G. Fejer, J. Sahr, W. E. Swartz, I. Haggstrom, A. Hedberg, J. A. Nordling

All Physics Faculty Publications

Two radars were used simultaneously to study naturally occurring electron heating events in the auroral E-region ionosphere. During a joint campaign in March 1986 the Cornell University Portable Radar Interferometer (CUPRI) was positioned to look perpendicular to the magnetic field to observe unstable plasma waves over Tromsø, Norway, while EISCAT measured the ambient conditions in the unstable region. On two nights EISCAT detected intense but short lived (< 1 min) electron heating events during which the temperature suddenly increased by a factor of 2–4 at altitudes near 108 km and the electron densities were less than 7 × 104 cm−3. On the second of these nights CUPRI was operating and detected strong plasma waves with very large phase velocities at precisely the altitudes and times at which the heating was observed. The altitudes, as well as one component of the irregularity drift velocity, were determined by interferometric techniques. From the observations and our analysis, we conclude that the electron temperature increases were caused by plasma wave heating and not by either Joule heating or particle precipitation.

Contact Resistance Measurements In Gaas Mesfet's And Modfet's By The Magneto‐Tlm Technique, David C. Look

Physics Faculty Publications

The standard transmission‐line model (TLM) for specific contact resistivity measurements of planar contacts is improved in two ways: (i) the addition of a magnetic field, which gives the mobility and carrier concentration of the bulk material, and the mobility of the material under the contact; and (ii) an extension to two layers, which makes the model applicable to MODFET structures. The results are applied to MESFET material, and MODFET material. One conclusion concerning the latter material is that the electrons directly beneath the annealed Au/Ge/Ni contacts have lower mobility than those in the bulk, but still …

Comparison Of Effective Medium Procedures For Optical Modeling Of Laminar Structures, David D. Allred, Robert F. Edgerton

Faculty Publications

This study addresses the question, "How can the optical properties of matter in ultrathin amorphous nonmetallic films in multilayers best be determined from reflectance (R) and transmission (T) measurements?" A blue shift in the band gap of plasma CVD a-Si:H/a-SiNx:H multilayers was reported several years ago. It was suggested that the shift in the band gap, Eg, Relative to bulk a-Si:H as given by the Tauç plot was due to quantum confinement effects. The purpose of this study is to evaluate the usefulness of various effective media theories (EMT) for determining the optical constants of materials in a multilayer and …

Discharge Suppression System For A Double Focusing, Atmospheric Pressure Ionization Mass Spectrometer, Andrew H. Grange, Robert J. O'Brien, Douglas F. Barofsky

Chemistry Faculty Publications and Presentations

An electrical discharge suppression system for a medium throughput (∼2 l/s) pumping line has been devised that works up to potentials of ±15 kV. This device permits atmospheric pressure ionization sources to be interfaced to high-resolution, magnetic sector mass spectrometers with source potentials of 6-10 kV

Solution Manual Of University Physics: Mechanics, Yimin Wang, Clifton Keller

All Books

No abstract provided.

Condensation Method For Humidity Measurement In The Umr Cloud Simulation Chamber., Donald E. Hagen, Daniel R. White, Darryl J. Alofs

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Cloud Simulation Facility Has Been Developed for the Study of Various Atmospheric Cloud Processes. the Initial Relative Humidity of the Air Sample Put into the Cloud Chamber is a Key Parameter in Virtually Any Experiment and Needs to Be Known Accurately. This Report Describes How the Cloud Simulation Chamber itself Has Been Used as a Condensation Type Hygrometer to Calibrate the System's Humidifier. Two Distinct and Physically Different Methods for Inferring Mixing Ratio Are Used, One Exploiting the Sensitivity of Aerosol Activation to Humidity, and the Other Exploiting the Sensitivity of the Rate of Growth of Cloud Droplets to …

An Optically Controlled Closing And Opening Semiconductor Switch, K. H. Schoenbach, V. K. Lakdawala, R. Germer, S. T. Ko

Electrical & Computer Engineering Faculty Publications

A concept for a bulk semiconductor switch is presented, where the conductivity is increased and reduced, respectively, through illumination with light of different wavelengths. The increase in conductivity is accomplished by electron ionization from deep centers and generation of bound holes. The reduction of conductivity is obtained by hole ionization from the excited centers and subsequent recombination of free electrons and holes. The transient behavior of electron and hole density in a high power semiconductor (GaAs:Cu) switch is computed by means of a rate equation model. Changes in conductivity by five orders of magnitude can be obtained.

Generation Of Moire Contours With Acousto-Optic Cells, Joel H. Blatt, Huey-Chin Chang Ho, Eddie H. Young

Aerospace, Physics, and Space Science Faculty Publications

Moire contours are seen on a curved surface viewed through a grating when the surface is illuminated with a matched grating. We have been able to replace both the projection and viewing physical gratings with gratings of variable spacing generated in acousto-optic cells, and have been able to observe and record Moire contours. The gratings are generated by amplitude modulating 70 MHz AO cells with a 1 to 10 MHz square wave. The gratings become visible on the curved object by strobing the illuminating laser beam with 50 nsec pulses by means of an AO modulator. Data is given showing …

Theoretical Thermodynamic Properties Of Low Temperature Fluids, Zul Azhar Zahid Jamal

Masters Theses

The thermodynamic functions for low temperature fluids are computed using parametric integral equations and perturbation theory. Parametric integral equation N is applied to a low temperature Lennard-Jones gas. It is found that there is no significant improvement over the better known parametric integral equation C. The two parameter integral equation T is applied to a low temperature square-well potential and is found to be unsatisfactory at reduced temperatures of T*= 1.4 and 1.6, but quite accurate at T* = 2.2. The equation T results for T* = 2.2 are used as the reference system in perturbation theory computations. Tables of …

University Of Missouri-Rolla Cloud Simulation Facility: Proto Ii Chamber, Daniel R. White, James L. Kassner, John C. Carstens, Donald E. Hagen, John L. Schmitt, Darryl J. Alofs, Alfred R. Hopkins, Max B. Trueblood, Max W. Alcorn, William L. Walker

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Graduate Center for Cloud Physics Research at UMR Has Developed a Cloud Simulation Facility to Study Phenomena Occurring in Terrestrial Clouds and Fogs. the Facility Consists of a Pair of Precision Cooled-Wall Expansion Chambers Along with Extensive Supporting Equipment. the Smaller of These Chambers, Described in This Article, is Fully Operational, and is Capable of Simulating a Broad Range of In-Cloud Thermodynamic Conditions. It is Currently Being Used to Study Water Drop Growth and Evaporation for Drops Nucleated (Activated) on Well-Characterized Aerosol Particles. Measurements Have Been Made Not Only for Continuous Expansions (Simulated Updraft) But Also for Cyclic Conditions, …

Angular-Differential Studies Of Excitation In Quasi-One-Electron Collisions At "High" Energy, E. Redd, Timothy Gay, D. M. Blankenship, John T. Park, Jerry Peacher, Denver G. Seely

Physics Faculty Research & Creative Works

Qualitative differences have been observed between two types of "quasi-one-electron" collision systems. We have studied valence-electron excitation at "high" energy (relative collision velocities up to 0.5 a.u.) in the Mg⁺+He and Na⁺+H collision systems, and find that while Mg⁺+He collisions are dominated by "direct" excitation, the Na⁺+H collisions exhibit significant "molecular" excitation, even at the highest velocities. This behavior can be understood in terms of the molecular structure of the respective collision complexes, and the energy separation between the ground and first excited states of the valence electron.

A Study Of Flow Separation In Transonic Flow Using Inviscid And Viscous Cfd Schemes, James Andrew Rhodes

Mechanical & Aerospace Engineering Theses & Dissertations

A comparison of flow separation in transonic flows is made using various computational schemes which solve the Euler and the Navier-Stokes equations of fluid mechanics. The flows examined are computed using several simple two-dimensional configurations including a backward facing step and a bump in a channel. Comparison of the results obtained using shock fitting and flux vector splitting methods are presented and the results obtained using the Euler codes are compared to results on the same configurations using a code which solves the Navier-Stokes equations.

Angular-Differential Studies Of Excitation In Quasi-Oneelectron Collisions At "High" Energy, E. Redd, Timothy J. Gay, D. M. Blakenship, J. T. Park, J. L. Peacher, D. G. Seely

Timothy J. Gay Publications

Qualitative differences have been observed between two types of "quasi-one-electron" collision systems. We have studied valence-electron excitation at "high" energy (relative collision velocities up to 0.5 a.u.) in the Mg⁺+He and Na⁺+H collision systems, and find that while Mg⁺+He collisions are dominated by "direct" excitation, the Na⁺+H collisions exhibit significant "molecular" excitation, even at the highest velocities. This behavior can be understood in terms of the molecular structure of the respective collision complexes, and the energy separation between the ground and first excited states of the valence electron.

The Effects Of A Mandatory Early Shutdown Of Maine Yankee, Maine State Planning Office

Maine Collection

The Effects of a Mandatory Early Shutdown of Maine Yankee

Maine State Planning Office - Richard Silkman, Director (September 1987).

Contents: Introduction / Legal Issues / Economic Issues / Health and Environmental Issues / Conclusions / Appendices

29th Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and abstracts from the 29th annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, August 2-6, 1987.

Synthetic Aperture Multi-Telescope Tracker Apparatus, Richard A. Carreras, Salvatore J. Cusumano, Morton B. Jenks, Robert I. Suizu

AFIT Patents

A plurality of telescopes provide output return signals which are applied both directly and in sampled form to a photo-detector cell. The detected signals from the photo-detector will represent the constant and transient errors of the telescope system. A low pass filter insures that the tracker provides only the constant or D.C. component of the error, while a high pass filter insures that the existing measuring devices for each telescope beam provide only the transient or A.C. component of the error. The A.C. and D.C. error signals are summed together with the appropriate applied gains on each channel such that …

University Of Missouri--Rolla Cloud Simulation Facility: Proto Ii Chamber, Daniel R. White, James L. Kassner, John C. Carstens, Donald E. Hagen, John L. Schmitt, Darryl J. Alofs, Alfred Raymond Hopkins, Max B. Trueblood, Max W. Alcorn, William L. Walker

Physics Faculty Research & Creative Works

The Graduate Center for Cloud Physics Research at UMR has developed a cloud simulation facility to study phenomena occurring in terrestrial clouds and fogs. The facility consists of a pair of precision cooled-wall expansion chambers along with extensive supporting equipment. The smaller of these chambers, described in this article, is fully operational, and is capable of simulating a broad range of in-cloud thermodynamic conditions. It is currently being used to study water drop growth and evaporation for drops nucleated (activated) on well-characterized aerosol particles. Measurements have been made not only for continuous expansions (simulated updraft) but also for cyclic conditions, …