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Articles 8491 - 8520 of 8853
Full-Text Articles in Physical Sciences and Mathematics
Computer Model Of A Fast Toroidal Plasma Compression, With Application To The Topolotron, H. Mark Nelson, Keith H. Brown, Charles A. Hart
Computer Model Of A Fast Toroidal Plasma Compression, With Application To The Topolotron, H. Mark Nelson, Keith H. Brown, Charles A. Hart
Faculty Publications
The method is developed for a comuputer sequence which models a fast toroidal theta or screw pinch for a highly conducting axially symmetric plasma. The computer sequence takes into account the self-inductances of the plasma and the external conductors which drive the compression as well as the mutual inductance which electromagnetically couples the two. The computer sequence is divided into three phases: a snowplow compression phase, an adiabatic compression phase, and a crowbarred circuit phase. The computer sequence is applied to a topolotron and an example is given of a magnetohydrodynamic equilibrium geometry for which the plasma surface possesses an …
Behavior Of A Manganin Coil At Elevated Temperatures And Pressures, Jonathan D. Weiss, Daniel L. Decker, H. B. Vanfleet
Behavior Of A Manganin Coil At Elevated Temperatures And Pressures, Jonathan D. Weiss, Daniel L. Decker, H. B. Vanfleet
Faculty Publications
We have determined the temperature dependence in the first-order pressure coefficient of a manganin coil to be dBetaB/dT= (4.2±0.8) ×10^-7 (kbar degrees C)^-1 in the equation R (T,P) =R (T,0)(1+BetaP+GammaP2), where R (T,P) is the coil resistance at temperature T and pressure P. The measurements were performed by simultaneously measuring the coil resistance and temperature at the transitions of mercury and bismuth, which were observed by differential thermal analysis.
Neutron Spectra At Zero Degrees From Proton Bombardment Of Light Nuclei At Medium Energies, Constantine George Cassapakis
Neutron Spectra At Zero Degrees From Proton Bombardment Of Light Nuclei At Medium Energies, Constantine George Cassapakis
Physics & Astronomy ETDs
The neutron-momentum spectra at 0° resulting from proton bombardment of 9Be, 12C, and 27Al at Tp=633MeV, and those of 12C and 27Al at Tp=786 MeV, have been measured at the LAMPF (Los Alamos Meson Physics Facility)-Nucleon Physics Laboratory.
The measurements utilized the recently developed single arm, multiwire proportional counter, recoil-proton, magnetic spectrometer. I
dentification of the recoil charged particles was achieved through momentum analysis and simultaneous timeof-flight determination for each particle constituting a valid event.
The momentum and energy resolutions achieved are about 1% and 1.4%, respectively, at the incident proton energies considered.
The spectra for 9Be and 27Al exhibit …
Ultraviolet Radiation Effects On Rotifers, Syed Asim Hussain
Ultraviolet Radiation Effects On Rotifers, Syed Asim Hussain
Masters Theses & Specialist Projects
The purpose of this investigation was to study ultraviolet radiation effects on rotifers. The rotifer studied was Philodina acuticornis odiosa Milne. Isolation cultures were used to grow the rotifers individually in separate U-plate depressions. The source of ultraviolet radiation consisted of four mercury germicidal lamps used in combination to deliver a uniform flux of 315 uW/cm2 over the sample. Five groups of rotifers, one control and four experimental groups of 96 each, were used. The rotifers used were 2-10 hours of age at the beginning of the experiment. The experimental groups were exposed to uv radiation for 3 minutes, …
"The Search For Extra-Terrestrial Life", Donald L. Devincenzi
"The Search For Extra-Terrestrial Life", Donald L. Devincenzi
Special Collections: Oregon Public Speakers
No abstract provided.
Sensitivity Of A Gas Filter Correlation Instrument To Variations In Atmospheric Profile And Earth Surface Temperatures, Joseph C. Casas
Sensitivity Of A Gas Filter Correlation Instrument To Variations In Atmospheric Profile And Earth Surface Temperatures, Joseph C. Casas
Physics Theses & Dissertations
The Gas Filter Correlation Radiometer Analyzer (GFCR), in application to the remote sensing of trace gases in the atmosphere, is potentially limited by the sensitivity of the measured upwelling thermal radiation to surface temperature and atmospheric temperature conditions. This study has been carried out to examine the principles of operation of the GFCR Analyzer and to obtain quantitative estimates of the errors produced in GFCR Analyzer measurements of CO (4.6μ), S02 (8.6μ), NH3 (11.0μ), and CH4 (8.1μ) resulting from uncertainties in the atmospheric temperature profile and ground temperature.
A simple mathematical prototype GFCR Analyzer was assumed. A line-by-line atmospheric radiative …
The Determination Of Double Mode Variable Star Periods, Arne A. Henden
The Determination Of Double Mode Variable Star Periods, Arne A. Henden
Physics & Astronomy ETDs
ABSTRACT
The problem of determining the periods of objects oscillating in one or more modes is discussed. Although the methods described are applicable to many different kinds of objects and observations, the discussion has been limited to double mode Cepheid stars.
Two methods of solution are followed in detail. An autocorrelation technique based on the scatter of points in an amplitude-phase plane is used for most cases. A means of calculating smoothed mean curves is discussed. A Fourier transform method is presented for closely spaced data points, with prewhitening included for accurate secondary period and amplitude determinations.
Three test problems …
A Satellite Study Of The High Energy Proton Environment Under The Radiation Belt, Kailash Chandra Dhingra
A Satellite Study Of The High Energy Proton Environment Under The Radiation Belt, Kailash Chandra Dhingra
Physics & Astronomy ETDs
Proton data outside of the South Atlantic Radiation anomaly (in the regions where hmin < 0) from the University of New Mexico High Energy Neutron and Proton Detector aboard OSO-6 satellite were analyzed in the present work. The detector was useful in the energy range from 75-145 Mev and the data were obtained during the period from August 1969 to January 1971. The altitude of the satellite varied from about 480 Km to 580 Km. Since the observed proton flux resulted from different source mechanisms a procedure was developed that allowed us to compute and separate the contributions made by different mechanisms in the observed protons. New evidence was derived from the study of the Down-Up asymmetry both along the field direction and the zenith of the look direction (ZAP angle) which substantiated the hypothesis that either one or both of the processes of the radial and the pitch angle diffusion play active roles in the origin and the distributions of the protons in the inner radiation belt. It was argued that processes drive the trapped protons in the radiation belt into the regions where stable trapping is not possible and thus contribute to the observed protons in these regions. We were further able to compute the total diffusing flux; however, it was assumed that both the Splash and the Re-entrant albedo proton fluxes were equal. Since this assumption was not very accurate, an incorrect estimation of the diffusing proton flux might have resulted. In addition to the above, the flux and the energy spectrum of the albedo protons were derived at three different regions. These were then compared with the results of other investigators. Discrepencies in both the flux and the energy spectrum were observed. Our flux value of 1.05 protons/m2 -sec-ster-Mev for the Re-entrant albedo at an energy of 85 Mev in the region where L = 2.5 was about a factor of two and a half higher than estimated by Ray (1967). No west-east asymmetry was observed in the true proton flux (proton flux obtained by subtracting the background contamination from the observed proton flux), within the limits of the experimental error. Since such an asymmetry was expected if we assume that the albedo protons alone constitute the true protons, it was concluded …
Gravitational Motion: An Interaction?, Frank H. Meyer
Gravitational Motion: An Interaction?, Frank H. Meyer
Journal of the Minnesota Academy of Science
"Non-implications" in Newton's Law of Gravitation are discussed to emphasize different approaches in two books treating the subject: Dewey Larson's Beyond Newton, and Gravitation, by Misner, Thorne and Wheeler. The author notes that the latter book ignores the possibility that gravitation may not be an interaction; while Larson accepts Newton's Law of Gravitation as a mathematically valid statement of Kepler's Laws of Planetary Motion, thus being applicable to the sun and planets even if they are not actually interacting.
Una Roca Lunar En Barcelona, Aldemaro Romero Jr.
Una Roca Lunar En Barcelona, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
E.S.A., N.A.S.A. Europea…, Aldemaro Romero Jr.
E.S.A., N.A.S.A. Europea…, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Sources Of Excitation Of The Interstellar Gas And Galactic Structure, J. J. Cowan, Menas Kafatos, W. K. Rose
Sources Of Excitation Of The Interstellar Gas And Galactic Structure, J. J. Cowan, Menas Kafatos, W. K. Rose
Mathematics, Physics, and Computer Science Faculty Articles and Research
The excitation of the interstellar gas. is discussed in the light of recent evidence from γ-ray, molecular, and 21-cm line observations. Previous studies of the excitation of the interstellar gas have not taken into account the substantial density contrast that exists between spiral arms and interarm regions. We examine the role played by the galactic distribution of three sources of excitation (supernovae, OB stars, and ultraviolet stars) in determining the physical state of the interstellar gas in arm and interarm regions.
Pole Stars Of Other Planets, Paul C. Sharrah
Pole Stars Of Other Planets, Paul C. Sharrah
Journal of the Arkansas Academy of Science
The north celestial pole of the Earth and the other planets is discussed. Right ascension and declination information on the location of the poles on the celestial sphere is summarized. The name of the brightest visible star near each pole is given and the special case of Uranus is discussed.
Thermal Instability In Supernova Shells, R. Mccray, R. F. Stein, Menas Kafatos
Thermal Instability In Supernova Shells, R. Mccray, R. F. Stein, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
Thermal instability in the radiative cooling region behind a shock will cause upstream density fluctuations to collapse into thin sheets aligned parallel to the shock front. A linearized calculation demonstrates the development of this instability. Thermal conduction suppresses the development of small-scale perturbations. Estimates of the scale sizes for the fully developed condensations agree roughly with the scale sizes of fine structure observed in supernova shells such as the Cygnus Loop.
A Theoretical Study Of The Predissociation Of The O2 B 3Ʃu- Electronic State, Richard Allan Harris
A Theoretical Study Of The Predissociation Of The O2 B 3Ʃu- Electronic State, Richard Allan Harris
Physics & Astronomy ETDs
It has been known for many decades that the B 3Ʃu- state of the oxygen molecule, the upper state of the Schumann-Runge electronic band system, is predissociated. The predissociation has been attributed to the 3Πu state, arising from the ground state, separated atom, manifold of molecular states, by previous investigators with the crossing point of the potential energy curves ranging from somewhere on the inner limb to somewhere on the outer limb of the bound excited B 3Ʃu- state. This research has been undertaken to quantitatively describe the observed predissociation. A model with adjustable parameters …
Pi-Meson Absorption On The Deuteron, Bruce Goplen
Pi-Meson Absorption On The Deuteron, Bruce Goplen
Physics & Astronomy ETDs
The nonradiative absorption of positive pi-mesons by deuterons is studied within the framework of Lagrangian formalism and the impulse approximation. The pi-nucleon absorption interaction is taken to be pseudovector; however, the reaction is believed to be dominated by pinucleon scattering. Thus, the main thrust of the investigation is directed at three different approaches to the scattering interaction. First, the Hamiltonian formalism of Koltun and Reitan is extended to include energetic pions. An off-shell form is chosen for p-wave scattering which at low energy reduces to the field-theoretical result of Klein. In the second approach, the S-matrix formalism of Lazard, Ballot …
Christian Astronomy Vs. Secular Astronomy, Richard G. Hodgson
Christian Astronomy Vs. Secular Astronomy, Richard G. Hodgson
Pro Rege
No abstract provided.
General Geodesic Motion In The Extended Kerr Manifold, Richard H. St. John
General Geodesic Motion In The Extended Kerr Manifold, Richard H. St. John
Physics & Astronomy ETDs
The timelike and null geodesics in the Kerr metric describe important properties of the space surrounding a rotating black hole. The general characteristics of these geodesics, with an emphasis on those on the axis of symmetry and the equatorial plane, are found in this paper. On the axis of symmetry, the behavior of all timelike and null geodesics is completely described. The accessibility of various spaces added for geodesic completeness in the extended manifold is found by making local observations of geodesics in one coordinate patch from geodesics in another. The analysis on the equatorial plane shows that for a …
Ultraviolet Photosimulated Thermoluminescence Of Lithium Flouride, Martin Payne
Ultraviolet Photosimulated Thermoluminescence Of Lithium Flouride, Martin Payne
Masters Theses & Specialist Projects
TLD-100 (lithium fluoride) thermoluminescence dosimeters are widely employed for the detection of ionizing radiations. This paper shows that these dosimeters may also serve as practical germicidal ultraviolet radiation dosimeters. To measure ultraviolet radiation, the TLD-100 dosimeters are first exposed to 500,000 roentgens of gamma radiation and then annealed at 300°C. Subsequent dosage of ultraviolet radiation may be determined by observation of photostimulated thermoluminescence of the crystal. The presented data indicate that the thermoluminescence response is linear for exposures up to 6,000 µjoule/cm2 and independent of exposure rate from 0.1 µ watt/cm2 to above 50 µwatt/cm2. Optical …
Neutron And Proton Measurements Of Oso-6 Near The South Atlantic Radiation Anomaly., Philip Jay Cooper
Neutron And Proton Measurements Of Oso-6 Near The South Atlantic Radiation Anomaly., Philip Jay Cooper
Physics & Astronomy ETDs
The University of New Mexico High-Energy Neutron Experiment flown aboard NASA Satellite OS0-6 in 1969 was designed and built to study neutrons at an altitude of 500 km, above the earth's dense atmosphere. The detector was a proton recoil telescope with directional discrimination and was sensitive to protons as well as neutrons. Neutron data from August, 1969 to January, 1971 was analyzed in the energy range 40-120 Mev. Proton data in the energy range 60-170 Mev obtained during October and November of 1969 was also analyzed. Analysis was limited to the region of space known as the South Atlantic Radiation …
Calculation Of Potential Functions For Pseudorotation In Five Membered Rings Using Energy Gradients In Extended HüCkel Theory, Thomas Robert Ferguson
Calculation Of Potential Functions For Pseudorotation In Five Membered Rings Using Energy Gradients In Extended HüCkel Theory, Thomas Robert Ferguson
Physics & Astronomy ETDs
The gradient of the energy in extended Hückel theory (EHT) was used in a variable metric algorithm to predict the energy along the pseudorotational path for several five membered ring molecules. The molecules studied were cyclopentane, tetrahydrofuran (THF), cyclopentanol, 4-tetrahydrofuranol, and cis- and trans-3,4-tetrahydrofurandiols. Comparisons of predictions for these molecules to experimental results were made to determine the capabilities of EHT prior to an intended study of sugar rings. A background chapter discusses the recent literature on nucleic acid constituents with emphasis on the geometries of five membered sugar rings. In crystals, these geometries are found to lie mostly in …
A Method For Measuring The Electrical Conductivity Of A Shocked Liquid, Richard James Hassman
A Method For Measuring The Electrical Conductivity Of A Shocked Liquid, Richard James Hassman
Physics & Astronomy ETDs
Development of a simple technique for the measurement of the gross electrical conductivity of a shock compressed liquid is attempted. A cell containing the sample is constructed from glass cylinders and aluminum foil. The foil is sandwiched between two cylinders of the same diameter to form a two compartment cylinder. The cylinder is mounted on a metal target plate. With both chambers of the system full of liquid, only insignificant reflections can arise from the sample-foil interface. A voltage is placed across the cell between the foil and the target plate, and the change in voltage as the shock front …
Hand Held Probe For Use In Electrical Sensing Of Plane Coordinates, George S. Hurst
Hand Held Probe For Use In Electrical Sensing Of Plane Coordinates, George S. Hurst
Physics and Astronomy Faculty Patents
A probe with a puncturing, electrically conducting needle is constructed to enable the user, whether right or left handed, to position the needle rapidly and accurately at a selected coordinate of a sensor package.
Ua77/1 Western Alumnus, Vol. 43, No. 4, Wku Alumni Association
Ua77/1 Western Alumnus, Vol. 43, No. 4, Wku Alumni Association
WKU Administration Documents
WKU alumni magazine. Features the following articles:
- Conway, Sheila. Competency Based Teacher Education
- Scarborough, John. Enthusiasm & Planning, Powerful One-Two Punch for Education
- Burkeen, Emmett. Counselor Education, A Study in Development
- Stuart, Robert. The Stage is His Classroom - Bill Leonard
- Just, Paul. Remember When, 1955-56
- Conway, Sheila. Women's Athletics Return
- Armstrong, Don. Biology for Real - Tech Aqua Biological Station
- Goldwater, Barry. On the Energy Crisis
- Porter, William. Third World Realities
- Muskie, Edmund. Restoring Our Confidence
- Dickey, Debbie. The Big Red Western Band
- Given, Ed. Instant Alumni
- Topper Power Carries WKU to National Finals - Football
- Jimmy Feix, Coach …
Mercurio: El Redescubrimiento De Un Planeta, Aldemaro Romero Jr.
Mercurio: El Redescubrimiento De Un Planeta, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Cometa Kohoutek: El Espectáculo Fracasado, Aldemaro Romero Jr.
Cometa Kohoutek: El Espectáculo Fracasado, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Nubes De Moléculas Orgánicas En El Espacio, Aldemaro Romero Jr.
Nubes De Moléculas Orgánicas En El Espacio, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Twenty Years Of Experience With The University Of Arkansas Planetarium, Paul C. Sharrah
Twenty Years Of Experience With The University Of Arkansas Planetarium, Paul C. Sharrah
Journal of the Arkansas Academy of Science
The Model A-1 Spitz planetarium was placed in operation at the University of Arkansas in 1954. It was moved to its present location in 1972 and has continued to have a much expanded use. More than 8,000 persons attended demonstrations between 1 August 1972 and 31 March 1974. Approximately one third of these were University students in classes and laboratories; the remaining two thirds were accounted for by school and other youth groups and the public demonstrations.
El Instituto Nacional De Técnica Aeroespacial, Un Ejemplo De Muchas Cosas, Aldemaro Romero Jr.
El Instituto Nacional De Técnica Aeroespacial, Un Ejemplo De Muchas Cosas, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Júpiter: Sencillamente Fantástico, Aldemaro Romero Jr.
Júpiter: Sencillamente Fantástico, Aldemaro Romero Jr.
Publications and Research
No abstract provided.