Astrophysics and Astronomy Commons^™

Intensity Correlation Spectroscopy Of Heme Proteins And Motile Microorganisms, Gordon E. Banks

Physics & Astronomy ETDs

The recently developed technique of autocorrelation of intensity fluctuations of Rayleigh (quasi-elastically) scattered light allows measurement of some dynamic properties of particles in solution. The origin of the intensity fluctuations and the form of the correlation spectra for various situations are discussed. The apparatus and methods are described along with methods of data reduction and sources of error. Measurements were made using a Spectra-Physics Model 125 (50mW) He-Ne laser (6328Å) in conjunction with a Saicor 43A 400 channel correlation and probability analyzer. The diffusion coefficient of cyanometmyoglobin was found to be D_{20, w} = (9.47 ± 0.28) x 10 …

Sensor Package For Electrical Sensing Of Plane Coordinates And Method Of Preparing The Same, George S. Hurst, William C. Colwell Jr.

Physics and Astronomy Faculty Patents

A sensor package for ready insertion in properly registered position upon, or for removal from, a cabinet employed in electrical sensing of plane coordinates, is constructed to provide accurate readings when pierced by a small manually operated cursor.

A method for manufacturing the package including the affixing of accurately spaced electrodes on the package, is disclosed.

Dynamic Impulse Calibration Of Sheet Loaded Explosive, William James Johnson

Physics & Astronomy ETDs

In the past, experimenters have used Sheet Loaded Explosive (SLE) to simulate the damage caused by x-rays to an ICBM as the result of a nuclear burst from an ABM. One of the attractive features of SLE is that it can also provide high impul3e levels for structural damage studies. Previous measurements of the usual shock parameters such as peak overpressure, ietonation velocity, and shock front definition with short time interval pressure transducers were not suitable for total impulse measurements. The High Explosive Impulse Responder (HEIR) was developed to fill the need for a simple, reliable and economical total impulse …

Effects Of Pressure On The Rotational Phase Transitions And Dielectric Properties Of Solid Cyclopentanol, David Nason Glidden

Physics & Astronomy ETDs

The dielectric constant and loss for solid cyclopentanol have been measured at hydrostatic pressures up to 2.5 Kbar for frequencies of 1 KHz to 5 MHz from 258 °K to 200 °K. Activation parameters have been calculated from the experimental data. In addition, activation parameters have also been calcuated from a fluctuation-barrier model for dipole reorientation and compare favorably with the experimental quantities. The dielectric constant shows that the phase transition from form I, with sperically symetric orientational freedom, to form II, with restricted orientational freedom, is readily brought about at these pressures. This phase transition was elucidated by an …

First Measurements Of Earth Albedo Neutrons In Space, James R. Place

Physics & Astronomy ETDs

NASA satellite OSO-6 carried as part of its payload a proton recoil telescope capable of detecting neutrons between 40 and 200 MeV with directional discrimination. Sixteen months of data from this instrument were analyzed with a view to determining properties of the earth albedo neutron flux above the atmosphere.

The variation of albedo neutron flux with geomagnetic latitude was found to be 1:4 between 0° and 40°. The angular distribution shows that about 40% fewer neutrons come upward from directly beneath the satellite compared to the number coming from a direction tangential to the top of the atmosphere. These results …

Light Scattering From Mammalian Cells., Albert Brunsting

Physics & Astronomy ETDs

Light scattering intensity functions for concentrically coated spheres (core diameter 7 mu and total sphere diameter 10 mu, approximately) have been computed. The coated spheres model many types of nearly spherical mammalian cells whose nuclei have a low relative refractive index (~1.05) and cytoplasm with a slightly lower relative refractive index (~1.03). Studies are made on the relationships between the scattering coefficients for nonadsorbing, spherically symmetric scatterers. The physical origin of these coefficients is examined for absorbing scatterers. Diffraction accounts for most of the light scattered in the forwards lobe, whereas at larger angles the coated sphere scattering patterns are …

X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve. I. Methods And Techniques, Keith H. Brown, J. Dean Barnett

Faculty Publications

A technique using the tetrahedral anvil high-pressure x-ray system has been developed to extract coherent x-ray intensity patterns of liquids near melting from measured scattering curves in the presence of high-background counts. Radial distribution functions for liquids along the melting curve to pressures of at least 50 kbar can be obtained. At each pressure scattering curves are recorded for the liquid and solid on opposite sides of the melting curve and a subtraction is made to eliminate background and incoherent scattering. Theoretical estimates of the thermal diffuse scattering from the solid are added to the appropriately corrected difference patterns to …

X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve Ii. Sodium, Keith H. Brown, J. Dean Barnett

Faculty Publications

Coherent x-ray diffraction patterns for liquid Na have been extracted from measured patterns at 0.5, 7.5, 17, and 43 kbar along the melting curve. The experimentally determined liquid structure factor and resulting radial distribution function are given at each pressure. The position of the principal x-ray intensity peak is reproducible to within 0.5% and shows shifts of the order of 12%. The resulting nearest neighbor distance in the radial distribution function also shifts 12% but is reproducible only to approximately 2%. The distribution functions obtained at points along the melting curve suggest a simple dimensional compression or scaling; however, a …

X-Ray Irradiation Apparatus In Which An X-Ray Source Is Energized Upon The Recording Of Irradiation Dosage Data, George S. Hurst, Norbert Thennard, Karl A. Schneider

Physics and Astronomy Faculty Patents

Apparatus for use in examining or treating patients with X-radiation or the like requires the making of a permanent record of the radiation applied. The operation of the radiation source is controlled in dependence upon the making of the record and the to radiation, or dose exposure is limited to a predetermined amount. A method is disclosed for safeguarding the patient and for producing a tangible record of the dose to which the patient is subjected.

Development Of The Oso-6 High-Energy Neutron Detector And Correlation Of Measured Solar Neutron Fluxes To Solar Flares, Frederick Young

Physics & Astronomy ETDs

In an attempt to understand certain of the high energy processes that occur in the solar and terrestrial atmospheres and the interplanetary medium a detector of 20 to 160 MeV neutrons had been designed and constructed for inclusion in the NASA Orbiting Solar Observatory, Satellite OSO-G, which was launched into a near circular orbit at approximately 500 km altitude in August 1969. Both the angle of incidence and the energy of the neutron are determined by a telescopic arrangement of four scintillation plastic counters (Pilot B; hydrogen to carbon ratio 1:1) which generates proton recoils and provides pulse heights for …

Β-Delayed Proton Decay Of 9c, David D. Allred, John E. Esterl, J. C. Hardy, R. G. Sextro, Joseph Cerny

Faculty Publications

The delayed-proton spectrum following the β decay of 9C (t1/2=126.5±1.0 msec) was found to consist primarily of a continuum extending from 13 to 1.5 MeV, the latter being the lowest energy observed. In addition to the previously observed peaks at 9.28 and 12.30 MeV (C.M.), possible peaks between 3 and 7 MeV have been tentatively identified.

Electrical Sensor Of Plane Coordinates, George S. Hurst, James E. Parks

Physics and Astronomy Faculty Patents

An inexpensive electrical sensor of plane coordinates employs juxtaposed sheets of conducting material having electrical equipotential lines extending across each sheet and arranged normal to each other. A probe upon touching each sheet at a selected intersection of the equipotential lines causes separate signals to be applied to one or more conventional information-indicating units.

Cellular Absorbed Dose Spectrometer (Cads) Data Reduction And Analysis., John T. Cervini

Physics & Astronomy ETDs

A detailed description of a space qualified linear energy transfer (LET) spectrometer is presented. The Cellular Absorbed Dose Spectrometer (CADS) is a prototype instrument which was launched on March 17, 1969 into an elliptical orbit. Its purpose was to obtain the first successful LET measurements in space; and, thereby provide additional data to assess the biological hazards of the near earth space environment, especially during periods of in­creased solar activity.

The physical processes that take place in the CADS in­strument are discussed, and a definition of linear energy transfer is given, as well as its relation to dE/dx. The performance …

Measurement Of The Average Solar Neutron Flux And Its Correlation With Solar Activity, Pyung Syk Ro

Physics & Astronomy ETDs

Data from the University of New Mexico High Energy Neutron Detector flown on NASA satellite OSO-VI arc analyzed with the aim of detecting neutrons from the sun. The detector is a proton recoil telescope capable of directional discrimination and responsive to neutrons of energies between 20 and 200 MeV with an effective average efficiency for this analysis of 10^-4 and an effective area of 80cm². The detector was located in a wheel compartment of OSO-VI and scanned the sun once per revolution of the wheel at a rate of 30 rpm. The satellite was launched on August …

Increasing The Efficiency Of A Surface Ionization Mass Spectrometer, Thomas Curtis Adams

Physics & Astronomy ETDs

An Avco surface ionization mass spectrometer (model 90,000) was installed at the Los Alamos Scientific Laboratory in February, 1968. Since that date this machine has been used as a production instrument for the isotopic analysis of uranium and plutonium samples. During 1969, it was realized that a problem inherent in the ionization mechanism of the instrument was degrading the accuracy of results, and that the number of man-hours expended in reducing data had become excessive. As soon as this situation became apparent, corrective action was initiated to reduce the effect of the ionization problem and to decrease the amount of …

High-Pressure Equation Of State For Nacl, Kcl, And Cscl, Daniel L. Decker

Faculty Publications

A calculation of the equation of state for NaCl from a Mie-Grüneisen equation was repeated using more accurate values of the zero-pressure compressibility. It was also extended to KCl and CsCl. An analysis of this approach to pressure calibration indicates that it will yield pressures with about the same accuracy as can be presently achieved by experimental measurements above 25 kbar, and thus furnishes a temporary practical pressure scale.

Intensity Ratios For Polarized Refracted Light Near The Critical Angle., Stephanie Layne Moore

Physics & Astronomy ETDs

It was undertaken to investigate the intensity ratio of refracted light polarized parallel and perpendicular to the plane of incidence. The primary object of the experiment was to obtain this ratio for light incident at very nearly the critical angle on a water-air interface, the light having first passed through the water. A laser was used to produce the light beam and the experimental results were compared with the theory propounded by Fresnel for infinite plane waves and elsewhere asserted to hold for bound plane waves. As this theory predicted a ratio of the square of the refractive index (n) …

Dielectric And Phase Behavior In Solid Cyclopentanol., Stephen John Dalich

Physics & Astronomy ETDs

The dielectric and phase properties of cyclopenthanol have been investigated using dielectric constant measurements and visual observations. As a result of these studies a model has been constructed which accounts for the observed dielectric and phase behavior in solid cyclopentanol.

From the dielectric studies three distinct solid forms have been identified in a region from the melting point at -17.5 C to -80 C. Two of these, forms I and II, are rotational phases, the third is nonrotational. The studies have concentrated on the two rotational forms and the transition between them.

The previously reported dielectric anomalies have been investigated …

Linear Pulsation Analysis Of Cluster Cepheid Variables, Charles E. Needham

Physics & Astronomy ETDs

Models for thirteen classical Cepheids found in galactic clusters or associations are analyzed. The models are calculated using the most recently published photometric data and theoretical evolutionary tracks. The linearized equations of mass, momentum and energy conservation are solved subject to an infinitesimal radial perturbation of each equilibrium model. The equations are first solved in the adiabatic approximation. This solution is then used as the initial value for the iterative solution of the non-adiabatic equations. The linearized analysis provides information on pulsation periods of fundamental and harmonic modes, stability against pulsations and phase differences between various physical parameters, such as …

Lamb-Mössbauer Factor Of Sodium Ferrocyanide, Daniel L. Decker, L. E. Lortz

Faculty Publications

Using a set of commercially prepared sodium ferrocyanide absorbers enriched to 91.2% Fe57 the Lamb-Mössbauer factor was measured to be 0.28±0.03. The thickness of Fe57 for these absorbers was measured using x-ray absorption techniques and was found to be considerably smaller than that advertised by the manufacturer even after correcting for the size of the ferrocyanide particles in the absorbers.

A Vibrational And Rotational Analysis Of Eight Simple Models Of The Hydrogen Molecule In The Ground State., Stuart Fleming Hayes

Physics & Astronomy ETDs

The object of this dissertation was the investigation of the influence on the delta G curve for H2 of polarization, enhancement of charge between the nuclei, and variation of the screening parameter. A better understanding of the influence of these factors could lead to progress in estimating more accurately the dissociation energies of diatomic molecules. Also to be investigated was the correlation between these factors and the vibrational and rotational spectroscopic constants, particularly Bv.

The Heitler-London combination of atomic orbitals (referred to as phi 1) was used in every wave function The atomic orbital 2pz was used in phi 2 …

X-Ray Induced Luminescence Of Sapphire And Ruby, Ivan Collier Jr.

Masters Theses & Specialist Projects

Over the past decade the luminescence properties of sapphire (∝-AL₂O₃) and ruby (Al₂O₃:Cr₂O₃) have been the subject of many investigations because of their importance in materials technology. Sapphire and ruby are at present used as lasing materials, radiation dosimeters, and as optical windows. In order that these operations may be made more efficient, and that other useful luminescent properties may be systematically explored and developed, much attention has been given to understanding the luminescent mechanisms from the standpoint of the physics of the solid state. However, mechanisms have …

A New Method In The Wkb Approximation, Raymond Pierce Engelke

Physics & Astronomy ETDs

A new WKB-like quantization rule is developed by means of a transformation method. This method makes use of a combination of a Liouville-like substitution and the Prüfer transformation. The only quality required of the potential is that it be twice differentiable on the real axis. The new quantization rule is an exact rule. However, some terms in the rule must be approximated before it can be evaluated for any particular potential function. An interesting feature of the derivation is that no asymptotic expansions are used -- unlike the usual development of the 1st order WKB quantization rule (FWKBQR). The terms …

Molecular Orbital Calculations To Determine Stable Conformations Of The Nucleotide Deoxycytidine-3'-Monophosphate., Marvin Lawrence Chatkoff

Physics & Astronomy ETDs

Extended Huckel, semi-empirical, molecular orbital analyses were performed for deoxycytidine-31 -monophosphate and cytidine-3'-monoohosphate corresponding to single nucleotides of double helical DNA and RNA to determine whether the experimentally derived models correspond to theoretically stable configurations. The A, B, and C models of DNA, and linearly interpolated intermediate con­figurations were investigated. For RNA, the experimental A configuration, a pseudo RNA nucleotide formed from the B configuration of DNA, and intermediate conformations were used.

From the B model of DNA the base was displaced and angles adjusted until close coordinate fits were obtained at the A and C configurations. Intermediate points were …

-Ray Induced Luminescence Of Ruby, Wayne Cooke

Masters Theses & Specialist Projects

Since the advent of the laser there has appeared a multitude of scientific papers describing the various parameters that would affect the lasing action of the ruby laser. Many investigations have been carried out to determine the efficiency of the R-line fluorescence in ruby: however very little work has been done concerning the X-ray-induced luminescence of ruby.

Certainly the applications to laser technology would be of sufficient importance to merit a study of ruby under continuous irradiation, although this was not the main stimulus that motivated this investigation. The original program of study was undertaken to determine if there existed …

Propagation Of Ultrasound In Plastic Crystals, Carl E. Scheie

Physics & Astronomy ETDs

The study of the organic solid state, and in particular of plastic crystals, is a relatively new branch of physics (1,2). Timmermans first surmised the existence of these solids from the anomalous values of the entropies of fusion. The solids possess many of the characteristics of liquids. They are easily deformed by pressure and they show dielectric properties that can be described on the basis of rotation of the molecules in their lattice positions. Still they have a definite crystal structure. Thus, even though the molecules are not symmetric, they appear to be to some degree because of the rotation. …

Rayleigh Hysteresis Shape: Its Relationship To Displacement Distance Of A Single Domain Wall In 50% Ni–Fe, R. C. Woodbury, M. R. Hunt

Faculty Publications

The need to measure the displacement distance of domain walls from equilibrium for very weak alternating fields (H ≪ coercive force) in bulk magnetic material has prompted a study of the possible use of the opening of the Rayleigh hysteresis loop to indicate the amount of wall displacement. This paper contains (1) a review of the theoretical relationship between hysteresis shape and the displacement distance of a domain wall, based upon defect-energy models of Rodbell and Bean, and Baldwin; and (2) an experimental approach which provides a measure of the wall displacements versus hysteresis shape for 50% Ni–Fe tape. Discrepancies …

Proposed Thermodynamic Pressure Scale For An Absolute High-Pressure Calibration, Daniel L. Decker, J. Dean Barnett

Faculty Publications

The field of high pressure has developed rapidly over the past few years to a point where relatively sophisticated experiments are being attempted. In many experiments it is no longer sufficient to qualitatively estimate the pressure or to base conclusions on experimental results tied to an empirical pressure parameter. One desires to accurately know the pressure dependence of physical quantities related to a true thermodynamic scale.

Measurement Of Cyclohexane Ultrasonic Velocity Using Photon-Phonon Scattering Interactions, Edward W. Taylor Jr.

Physics & Astronomy ETDs

The construction of a frequency modulated optic cell and its operation for studying the ultrasonic velocities of cyclohexane, acetone and ethyl alcohol as a function of temperature is described. A description of photon-phonon scattering interactions is presented. The appearance of the intensity distribution of the scattered light is treated, and an analysis of the experimental results is included. The special scattering case of Bragg diffraction of coherent light was used for determining the ultrasonic velocities of cyclohexane as a function of temperature. Ramifications of the Raman-Nath and Bragg diffraction effects are discussed. The relationship v_T = 1376.78 - 5.25 …

Fission Barriers And Transition-State Spectra For 232th, 234th, 238u, 240u, 242pu, And 244pu From 9t, Pf0 Reactions., James D. Cramer

Physics & Astronomy ETDs

Joliot and Curie’s discovery of artificially induced radio-activity in several nuclei by a-particle bombardment encouraged Fermi and his collaborators in 1934 to attempt similar experiments using neutron bombardment of various target elements/ Using natural uranium as a target material they discovered at least four radioactive products, assumed to be elements in the transuranium region. These experiments were repeated in 1937 by Meitner, Hahn and Strassman in Germany where they found that some of these radioactive elements produced by neutron bombardment of uranium had barium-like chemistry, and were assumed to be isotopes of radium. Further investigation proved that these products could …