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Diffusion of Slow Electrons in Gases (open access)

Diffusion of Slow Electrons in Gases

The properties of electrons in a gas and an external electric field, e.g., agitation velocity, free path, energy lost per collision, and collision cross sections, were determined for electrons of energy less than 2 ev in a large number of gases. The computations were made from previously measured values for Townsend's energy factor or the ratio of electron agitation energy to molecule thermal energy. Results are presented for hydrogen, nitrogen, carbon dioxide, methane, ethylene, cyclopropane, and argon. (D.L.C.)
Date: October 24, 1961
Creator: Forester, D. W. & Cochran, L. W.
System: The UNT Digital Library
Transient Temperature Distributions in a Thermally Orthotropic Plate With Non-Uniform Surface Heating (open access)

Transient Temperature Distributions in a Thermally Orthotropic Plate With Non-Uniform Surface Heating

ent temperature variation in a thermally orthotropic plate which is subjected to an arbitrary heating rate distribution along one face with all other surfaces being insulated. Dimensionless temperature histories and distributions determined from this solution are presented for the special, but representative, case of a linearly varying heating rate distribution on plates with varying degrees of thermal orthotropy. These results establish quantitatively the value of a material with high planar and low normal thermal conductivities for applications where it is desired to maintain minimum temperatures on the rear or unheated surface of a heat shield when the heated surface is subjected to a very non-uniform heating rate distribution. The applicability of simplifying assumptions in analyzing such a system is discussed. Experimental temperature measurements in a pyrolytic graphite plate heated by an oxyacetylene flame were made to verify the analytical results. Achievement of satisfactory agreement wss found to be dependent upon use of thermal property values differing from those presently available for this material. This is not unusual in that differences in production methods are known to introduce substantial property variations in anisotropic materials such as pyrolytic graphite. (auth)
Date: June 1, 1961
Creator: Hornbaker, David Ross
System: The UNT Digital Library
Noise Considerations in Nuclear Pulse Amplifiers (open access)

Noise Considerations in Nuclear Pulse Amplifiers

The effects of certain pulse-shaping networks on the signal-to-noise ratio of a nuclear pulse amplifier were considered. The shaping networks discussed are: equal RC-integrating and RC-differentiating time constant, single- delay-line clipper and RC integrator, and doubledelay-line clipper and RC integrator. The effects of these networks on the signal, when high count rates and overload pulses are present, were also considered. Equations and curves were developed for the energy resolution (signal-tonoise ratio) and resolving time (related to the ability to operate at high counting rates) of the networks. Experimental results are shown for the energy resolution of the types of pulse- shaping networks considered. (auth)
Date: December 20, 1961
Creator: Landis, D. A.
System: The UNT Digital Library
A Theoretical Study of the Transient Operation and Stability of Two-Phase Natural Circulation Loops (open access)

A Theoretical Study of the Transient Operation and Stability of Two-Phase Natural Circulation Loops

Mathematical models of the time-dependent behavior of two-phase natural- circulation loops were used to predict the operation and to explain the unusual instability sometimes observed. The initial results obtained for a loop similar to the Univ. of Minnesota loop were used to formulate a more complex and accurate model, and the predicted transient behavior was in close agreement with the experimental results from the Minnesota loop. For a 300psia, high-pressure loop, unstable oscillatory behavior was predicted under certain conditions and stable behavior under others. Closed unstable regions rather than limits were predicted, and the specifications of stability in terms of a single parameter were found to be impossible. The great difference in oscillatory frequencies observed at low and high pressures was found to be due largely to the system geometry. The criterion for the absence of oscillations was found to be similar to one of the criteria for stability of chemical reaction systems. (D.L.C.)
Date: June 1, 1961
Creator: Garlid, K.; Amundson, N. R. & Isbin, H. S.
System: The UNT Digital Library
Dynamic Simulation of Multi-Pass Pressurized Water Nuclear Power Plants by Analog Computer Techniques (open access)

Dynamic Simulation of Multi-Pass Pressurized Water Nuclear Power Plants by Analog Computer Techniques

A kinetic model of the primary loop of a multi-pass pressurized water reactor power plant is developed to evaluate, by analog computer techniques, the transient response characteristics under conditions of steam generator load and reactor control rod perturbations. Using the 2-pass 28 Mw(t) SM-2 reactor as a typical plant, transient behavior patterns are illustrated and examined for a variety of load inputs, variations in plant constants, and analog model simplifications. (auth)
Date: June 1, 1961
Creator: Brondel, J. O.
System: The UNT Digital Library
Solid State Neutron Detectors (open access)

Solid State Neutron Detectors

None
Date: May 1, 1961
Creator: Murphy, J. F.
System: The UNT Digital Library
Ejection of Large Fragments in High-Energy Nuclear Reactions (open access)

Ejection of Large Fragments in High-Energy Nuclear Reactions

Several features of the production of Na/sup 24/ and Mg/sup 28/ fragments produced in the interaction of protons and He ions with Cu, Ag, Au, and U were investigated. Formation cross sections were determined for He ions of different energies between 320 and 880 Mev and for protons of 700 Mev. Thick- target recoil experiments were performed at bombarding energies of 0.7 and 3 Bev for protons, and 880 Mev for He ions. Also given are some recoil measurements of Na/sup 24/ from Al. Analysis of data obtained with target materials heavier than Al showed that for the bombarding energies used, Na/sup 24/ and Mg/sup 28/ are probably produced by the cleavage of the target nucleus into two heavy fragmerts. One of these fragments has a mass approximately equal to the mass Na 4 or Mg/6 and the other contains most of the remaining mass of the target nucleus. However, Na/sup 24/ and Mg/sup 28/ are very probably not slowly evaporated particles nor products of a slow fission process. The experimental information covering fragmentation from photographic emulsion studies and radiochemical studies is discussed. The various mechanisms proposed are considered and a new one suggested. According to this new mechanism Na/sup …
Date: September 1, 1961
Creator: Crespo, V. P.
System: The UNT Digital Library
Heavy-Ion Elastic Scattering (open access)

Heavy-Ion Elastic Scattering

The elastic scattering of C/sup 12/ ions from Ar, Fe, Ni, Ag/sup 107/ In, and Ta was measured as a function of angle, at a laboratory-system energy of 124.5 Mev with the Berkeley heavy-ion linear accelerator. The experimental equipment and techniques are discussed. The angular distributions show the same general behavior as previous heavy-ion elastic scattering experiments. The experimental data were analyzed with the semiclassical Blair model as modified by McIntyre. Very good agreement with experiment was obtained. The measurements were taken with 1% statistics in order to study the structure of the angular distributions in greater detail, because only by fitting the details in the structure was it possible to obtdin unambiguous sets of parameters. The parameters indicated a nuclear radius of 1.45A/sup 1/3/ x 10/sup -13/ cm, and a nearly constant surface thick ness of 1.6 x 10/sup -13/ cm. Total reaction cross sections were obtained. A rainbow-model analysis by Goldman of the data is given. Existing alpha - and heavy-ion scattering data were analyzed with the McIntyre model and compared with previous optical-model analyses of the same data. It was found that, by independent analysis, the two models give the same imaginary phase shifts for all partial …
Date: April 17, 1961
Creator: Alster, Jonas
System: The UNT Digital Library
Downflow Forced-Convection Boiling of Water in Uniformly Heated Tubes (open access)

Downflow Forced-Convection Boiling of Water in Uniformly Heated Tubes

None
Date: August 21, 1961
Creator: Wright, R. M.
System: The UNT Digital Library
Proton Capture Gamma Rays From Si$Sup 28$ in the Region of the Photonuclear Giant Resonance (open access)

Proton Capture Gamma Rays From Si$Sup 28$ in the Region of the Photonuclear Giant Resonance

The Livermore 90 deg inch variable-energy cyclotron was used to measure the 90 deg excitation function for the Al/sup 27/(p, gamma )Si/sup 28/ reaction. Proton energies between 5 and 13 Mev were used which gave excitation energies in Si/sup 28/ corresponding to the region of the photonuclear giant resonance. Two gamma rays were observed: gamma /sub O/, the groundstate gamma ray and gamma / sub 1/ resulting from deexcitation through the first excited state of Si/sup 28/ at 1.78 Mev. They were detected by a 5-in.-diam by 6-in.-long NaI(Tl) crystal. A Pb collimator was used to improve the resolution of the detector. The results indicated that both gamma /sub O/ and gamma /sub 1/ display the giant resonance behavior; the gamma /sub O/ carve reached a peak value of approximately -8 mu barns/sr at E/sub p/ = 8.75 Mev, while the gamma /sub 1/ peak was approximately -14 mu barns/sr at E/sub p/ = 10 Mev. Both curves displayed the fine structure previously reported by Gove et al. A detailed balance calculation was made, using the gamma /sub O/ data. A comparison with the measurements of Johansson on the total yield of protons from the Si/sup 28/( gamma ,p)Al reaction …
Date: May 1, 1961
Creator: Gardner, C. C.
System: The UNT Digital Library
Movement for Orchestra (open access)

Movement for Orchestra

The form of the movement is as follows: Slow introduction; forceful theme "A"; lyrical theme "B"; bridge between second theme and development section; development of theme "B"; another bridge developed from a fragment introduced immediately preceding the bridge which is used for a climax before theme "C" is introduced and developed. with the end of the development of theme "C", the development section ends, and thus begins the recapitulation of themes "B" and "A" in that order with little variation in either from that of the exposition. Theme "C", since it played such an integral part in the development section, is not brought back in the recapitulation.
Date: August 1961
Creator: Powell, Morgan, 1938-
System: The UNT Digital Library
Sinfonietta (open access)

Sinfonietta

"SINFONIETTA" is constructed on a free usage of the traditional Sonata-form. It has an introduction; an Exposition, with two principal themes; a Development, in which both principal themes are used; and a Recapitulation, in which both principal themes are combined.
Date: August 1961
Creator: Pickering, Robert Leroy
System: The UNT Digital Library
Essay for Orchestra (open access)

Essay for Orchestra

The Essay for Orchestra combines three contemporary styles of melodic writing into sonata form. The exposition contains three themes. The first theme is a twelve-tone row. Unlike the usual approach to serial writing, the row is used in its original form throughout the piece and is developed by rhythmic alterations. The theme never occurs in its inversion or retrograde. The second theme of the exposition illustrates a chromatic type of melody. The third theme in the exposition is constructed of ascending and descending leaps of perfect fourths interspersed with leaps of thirds and short scale lines. The constant use of this theme throughout the development section provides the composition with a melodic unity.
Date: January 1961
Creator: Payne, Frank Lynn
System: The UNT Digital Library
THE CARRIER-RECOMBINATION BEHAVIOR AND ANNEALING PROPERTIES OF RADIATION- INDUCED RECOMBINATION CENTERS IN GERMANIUM (open access)

THE CARRIER-RECOMBINATION BEHAVIOR AND ANNEALING PROPERTIES OF RADIATION- INDUCED RECOMBINATION CENTERS IN GERMANIUM

Carrier recombination and annealing of radioinduced recombination centers were investigated for both n- and ptype Ge. The experimental results are explained by a model in which recombination occurs at 0.36 ev above the valence band in gamma -irradiated, n-type Ge; the position of this level is shifted slightly downward for neutron-irradiated Ge. Trapping levels occur in As-doped Ge (at 0.17 ev above the valence band) which are not present in Sb-doped Ge. For p-type Ge, an energy level present in unirradiated Ge acts as a trapping center. A value for the electron capture cross section of n-type Ge is derived: 7 x 10/ sup -//sup 1//sup 9/ cm/sup 2/. The annealing properties of Sb- and As-doped Ge are very different. A model for the annealing results is given in which irradiation produces three major types of defects: interstitials, vacancies, and vacancy-interstitial pairs. The properties of each defect type are described. Association of vacancies with doping atoms is discussed. (D.L.C.)
Date: June 1, 1961
Creator: Curtis, O.L. Jr. & Crawford, J.H. Jr.
System: The UNT Digital Library
The Magnetic Properties of Deformed Nuclei (open access)

The Magnetic Properties of Deformed Nuclei

It is shown that the magnetic moments of odd-A deformed nuclei can be interpreted in terms of the independentparticle model with interconfigurational mixing due to the very-short-range residual forces. The latter are implied by using the empirically reduced spin gyromagnetic ratios. The effects of these residual forces on the collective gyromagnetic ratios g/sub R/ are discussed in terms of pair correlation. The effect of particle-rotation interaction on the magnetic moment and the collective gyromagnetic ratio are shown. The g/sub R/ values are obtained from the magnetic moments and the matrix elements for M1 transitions in tais band. It is found that these mechanisms give a satisfactory account of the collective gyromagnetic ratio of Dy/sup 161/, Ho /sup 165/, Er/sup 167/, and Hf/sup 179/. (auth)
Date: April 1, 1961
Creator: Chiao, L.
System: The UNT Digital Library
The Cosine-Cubed Neutron Spectrometer (open access)

The Cosine-Cubed Neutron Spectrometer

In an attempt to increase the efficiency, a proton recoil neutron spectrometer was built in which the proton detection crystal is in the shape of the surface formed by the rotation of the cos/sup 3/ THETA curve about the THETA = 0 axis where THETA is the angle between the direction of travel of the incident neutron and the direction of travel of the recoil proton. Such a construction makes the detector crystal conform to the range envelope of the protons recoiling from a neutron beam of sufficiently high energy into a gas in which the proton range is proportional to the 3/2 power of the proton energy. Sixteen pieces of thallium-activated cesium iodide were assembled as a mosaic arranged in the cos/sup 3/ THETA shape so that the maximum THETA was 30 deg . Calculations show that 25% of the protons recoil within 30 deg . The Po-Be snd Po-B spectra were measured with the instrument using xenon in the chamber. The resolution of the spectra obtained was low due to nonuniform pulse height response of the CsI crystal sections and excessive gamma-ray response even though sn anthracene proton radiator was used in a coincidence scheme designed to minimize …
Date: May 1, 1961
Creator: Thorngate, J. H.; Hurst, G. S.; Davis, F. J. & Reinhardt, P. W.
System: The UNT Digital Library
Low-Energy Pion-Photon Interaction: The (2$pi$,2$gamma$) Vertex (open access)

Low-Energy Pion-Photon Interaction: The (2$pi$,2$gamma$) Vertex

None
Date: April 20, 1961
Creator: Desai, B. R.
System: The UNT Digital Library
An Analysis of the Absorption Spectra of Tm(IV) and Am(IV). (open access)

An Analysis of the Absorption Spectra of Tm(IV) and Am(IV).

None
Date: January 1, 1961
Creator: Gruber, J. B.
System: The UNT Digital Library
Design and Properties of a Neon Filled Spark Chamber in a Magnetic Field (open access)

Design and Properties of a Neon Filled Spark Chamber in a Magnetic Field

Introduction: Recently a new type of charged particle detector, the so-called spark chamber, has been developed. The detector has certain advantages in high energy physics over bubble chambers aside from its much lower cost.
Date: May 1, 1961
Creator: Heyn, Maarten P.
System: The UNT Digital Library
The Brahms Variations on a Theme of Paganini and the Rachmaninoff Rhapsody on a Theme of Paganini (open access)

The Brahms Variations on a Theme of Paganini and the Rachmaninoff Rhapsody on a Theme of Paganini

Born April 2, 1873, on the estate of Oneg in the province of Novgorod, Russia, Sergei Vassilyvitch Rachmaninoff was the fifth of the six children of Vassili and Lyoubov Boutakova Rachmaninoff. Rachmaninoff's aristocratic descent was traced to the Hospodars Dragosh, rulers of the realm of Molday from the fourteenth to the sixteenth century. One of the daughters from this family had married a son of the Grand Duke Ivan III of Moscow. The son's nephew was named Rachmanin, and from this source the family name originated.1 Rachmaninoff's mother was the daughter of a general, head of Araktcheyev Military College in Novgorod and the owner of a number of estates in the district. It was with a dowry of five of these estates that Lyoubov Boutakova married Vassili Rachmaninoff, and on one of these estates, Oneg, the couple settled down to married life.
Date: June 1961
Creator: Teel, Carl Brown
System: The UNT Digital Library
The Treatment of the Chorale Wie SchöN Leuchtet Der Morgenstern in Organ Compositions From the Seventeenth Century to the Twentieth Century (open access)

The Treatment of the Chorale Wie SchöN Leuchtet Der Morgenstern in Organ Compositions From the Seventeenth Century to the Twentieth Century

The chorale Wie schðn leuchtet der Morgenstern was popular from its very outset in 1589. That it has retained its popularity down to the present day is evident by its continually appearing in hymnbooks and being used as a cantus in organ compositions as well as forming the basis for other media of musical composition. The treatment of organ compositions based on this single chorale not only exemplifies the curiously novel attraction that this tune has held for composers, but also supplies a common denominator by which the history of the organ chorale can be generally stated.
Date: August 1961
Creator: Renick, Paul Winston
System: The UNT Digital Library
Béla Bartók's Use of Percussion Instruments (open access)

Béla Bartók's Use of Percussion Instruments

The first chapter outlines the history of percussion instruments used by Béla Bartók, The second chapter deals with the use of percussion by various composers from Bach's time up to the period of Bartók. Chapter three outlines how Bartók uses percussion instruments.
Date: August 1961
Creator: Stephenson, Duke Hopkins
System: The UNT Digital Library
Preludes, Opp, 15, 35, and 74 of Alexander Scriabin (open access)

Preludes, Opp, 15, 35, and 74 of Alexander Scriabin

The five Preludes, Op. 15 were composed in the year 1897 while Scriabin was occupied in concert tours with his friend and publisher, Beliaef. This year brought no less than forty-seven short preludes written at various times and collected in five sets: Opp. 11, 13, 15, 16, and 17. These preludes, though clever and original in melody, show the great influence of Chopin on Scriabin.
Date: January 1961
Creator: Buckingham, Wilna Faye
System: The UNT Digital Library
Anxiety in Elementary School Children as a Function of Intelligence, Self-Concept and Ordinal Birth Position (open access)

Anxiety in Elementary School Children as a Function of Intelligence, Self-Concept and Ordinal Birth Position

It shall be the purpose of this study to continue this delineation of the dynamics of anxiety. An attempt shall be made to study the nature of anxiety, especially in elementary school children, as it relates to three other factors: namely, intelligence, self-concept and ordinal birth position.
Date: August 1961
Creator: Scott, Myrtle M.
System: The UNT Digital Library