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Diffusion of Slow Electrons in Gases

Description: 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.
Partner: UNT Libraries Government Documents Department
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A Study of the Kinetic and Mechanical Properties of a Stabilized Beta Phase Plutonium Alloy

Description: The elements Sn, Mg, Ti, Zr, Hf, Si, Cd, and U were alloyed with plutonium to determine their effect on stabilization of the beta phase. Zirconium was found to be the ' most effective. Kinetic studies were conducted on Pu-Zr alloys having 0.24, 0.65, and 1.7 at.% Zr contents. The beta to alpha transformation in the Pu-Zr alloys was somewhat similar to that in unalloyed plutonium. The main difference being that time, temperature, transformation curves of the alloys were shifted to the right as the zirconium concentration increased. It was determined that the amount of beta phase retained at room temperature increased as the zirconium concentration increased. The minimum amount of Zr needed to stabilize the beta phase of plutonium at room temperature was determined to be 2.0 at.%. A 2.4 at.% Zr addition stabilized the beta phase of plutonium at atmospheric pressure from room temperature to 265 deg C. During mechanical property testing it was determined that the stabilized beta Pu-2.4 at.% Zr alloy was brittle from room temperature to 230 deg C. Both tensile and compression strengths of the beta stabilized alloy were greater than the unalloyed beta phase of plutonium. A brittle-ductile transition was noted between 130 and 180 deg C on the Pu-0.65 at.% Zr alloy. Age hardening studies were conducted at room temperature with a Pu -2.4 at.% Zr alloy. A slight aging effect was noted due to the precipitation of an intermetallic compound. Compression tests on the Pu-2.4 at.% Zr alloy indicated that below 80 deg C the stabilized beta phase started to transform to alpha phase during the application of compressive loads. (auth)
Date: January 1, 1962
Creator: Taylor, J. M.
Partner: UNT Libraries Government Documents Department
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Transient Temperature Distributions in a Thermally Orthotropic Plate With Non-Uniform Surface Heating

Description: 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
Partner: UNT Libraries Government Documents Department
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Noise Considerations in Nuclear Pulse Amplifiers

Description: 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.
Partner: UNT Libraries Government Documents Department
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String Quartet

Description: The first movement of the "String Quartet" opens with a gradual unfolding of the lead motive in the first six measures of the section marked "Largo." The second theme is heard in the first two measures of the section marked "Moderato" after a false start by the first violin. The third movement utilizes the essential dance characteristics of the "Minuet" marking.
Date: June 1963
Creator: Riley, James.
Partner: UNT Libraries
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Concerto for Trumpet and Orchestra

Description: Like the trumpet concertos of Haydra and Hummel, the present concerto for trumpet and orchestra is set in the classical plan of three movements: fast, slow, and fast. The total duration is approximately twenty minutes. The instrumentation of the orchestra, reveals an ensemble of moderate proportions.
Date: August 1965
Creator: Tull, Fisher
Partner: UNT Libraries
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Sonata for Two Pianos

Description: The Sonata for Two Pianos, eighteen in duration, is in the form of a large arch. The arch is constructed by relating the last movement to the second and first movements by borrowing material from these movements. The resulting form is a large ABA comprising the entire composition. The arch is superimposed over a more traditional formal concept of sonata. A sonata-allegro form is distinguishable in the first movement, a fantasia-variations in the second, and a modified sonata-allegro in the final movement.
Date: July 1966
Creator: Calhoon, William H. (William Henry), 1937-
Partner: UNT Libraries
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Sound Study

Description: Sound Study is a composition for large symphony orchestra in the twelve-tone idiom. It is a one-movement, monothematic piece in a large ternary form. The main body of the work is preceded by a long introduction which includes statements of the single thematic idea. The A section of the piece is scherzo-like in character and in a moderate 6/8 tempo. The theme is announced and receives a variety of treatment in this section. The B section is an extensive development of thematic material and utilizes a reverberation effect to be discussed below. A brief return of the A section brings the piece to a close.
Date: August 1966
Creator: Haerle, Dan
Partner: UNT Libraries
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New York Cycle

Description: New York Cycle consists of the settings of three poems for bass-baritone voice and eight instruments. The poems, each of which serves as the basis for one movement, are "The East River's Charm" by Samuel Bernard Greenberg, "Brooklyn Bridge" by Vladimir Mayakovsky, and "The Skyscraper Loves Night" by Carl Sandberg. The instrumentation employed consists of two French horns, vibraphone, timpani, and string quartet.
Date: August 1965
Creator: Ehle, Robert C.
Partner: UNT Libraries
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Concertino for Orchestra

Description: Concertino for Orchestra is a one-movement composition of rhapsodic character. The treatment of form and orchestration resembles that of the first movement of a concerto. The piece is in modified sonata form, containing two exposition-development sections. The orchestration employs a wide range of tonal colors, and has been used extensively in this piece to emphasize textural development. Each group of instruments is used individually in solo style, and yet the orchestral tutti never assumes the secondary role of accompaniment.
Date: August 1963
Creator: Wirtel, Thomas
Partner: UNT Libraries
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Essay for Orchestra

Description: 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
Partner: UNT Libraries
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Sinfonietta

Description: Sinfonietta is a one-movement piece for full symphony orchestra. The work contains five themes, three of which are the more important. The remaining two are subordinate because they are shorter, and not as fully developed as the A themes. A diagram of the form of the piece is shown on the following page as Figure 1. The duration of the work is approximately 14 minutes.
Date: August 1965
Creator: Morgan, Bob, 1941-
Partner: UNT Libraries
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Three Units

Description: Three Units is a symphony in three movements: fast-slow-fast. The general shape or large form of each unit is noticeably different from its counterparts, although all three exhibit a common feature: an evolutionary process in which one or more musical genres form the basis for the entire movement.
Date: May 1969
Creator: Oldfield, W.A. (Willard Alan), 1935-
Partner: UNT Libraries
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A Theoretical Study of the Transient Operation and Stability of Two-Phase Natural Circulation Loops

Description: 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.
Partner: UNT Libraries Government Documents Department
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Low Temperature Thermoluminescence of Gamma Irradiated Potassium Dihydrogen Phosphate

Description: Thermoluminescence in potassium dihydrogen phosphate (KDP) induced by Co/ sup 60/ gamma irradiation at liquid nitrogen temperature (-198 deg C) was investigated. Glow curves in the temperature range --196 to 0 deg C were measured for a series of gamma exposure dosages ranging from 10/sup 4/ roentgen to 5 x 10/sup 6/ roentgen. The heating rate used for glow curve measurements was 12 deg C per minute. Twice recrystallized Mallinckrodt reagent grade potassium dihydrogen phosphate, with a grain size between 100 and 170 mesh, was used for most samples. In the case of the powder samples, the glow curve for an exposure dose of 10/sup 4/ roentgen exhibited two peaks in this temperature range, one at approximately --78 deg C and the other at approximately -146 deg C. The -78 deg C peak split into two distinct peaks with increasing dosage. At still higher doses an additional peak at about -9 deg C became evident. This peak may, however, be due to aluminum oxide. Calculation of the trap depth, E, and the frequency factor, s, associated with the --78 deg C peak, by the approximate method of Grossweiner yielded values of 0.485 ev and 9.97 x 10/sup 10/ sec/sup -1/ for E and s, respectively. Calculation of the trap depth corresponding to this glow peak was also made using the method described by Bonfiglioli, Brovetto, and Cortese. The value obtained was approximates -0.2 ev. Treatment of the --148 deg C glow peak by the method of Bonfiglioli, Brovetto, and Cortese gave values of approximates 0.1, approximates 0.35, and approximates 0.2 ev for glow curves resulting from exposure doses of 10/sup 4/, 10/sup 5/, and 10/sup 6/ roentgens, respectively. Glow curves were measured for two KDP single crystals, each exposed to 10/sup 4/, 10/sup 5/, and 10/sup 6/ roentgens with subsequent …
Date: October 19, 1962
Creator: Sims, T. M.
Partner: UNT Libraries Government Documents Department
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The Specific Heat of Dysprosium Metal Between 0.4 and 4 K

Description: Submitted to Illinois Inst. of Tech., Chicago. A He/sup 3/ cryostat was built to measure the specific heat of rare earth metals which have a component, at low temperatures, attributable to the electrons in the incomplete 4f shell. The specific heat of dysprosium from 0.4 to 4.2 deg K was measured. Pertinent theories about specific heats are outlined. The apparatus included the cryostat, vacuum and He/sup 3/ systems, calorimeter, carbon thermometer, heater, and magnetic thermometer. The experimental procedure is described and results are presented in graphic and tabular form. The specific heat rose sharply below 1 deg K. An anomalous hump was centered about 2.35 deg K. (M.C.G.)
Date: August 1, 1962
Creator: Guenther, R. A.
Partner: UNT Libraries Government Documents Department
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Dynamic Simulation of Multi-Pass Pressurized Water Nuclear Power Plants by Analog Computer Techniques

Description: 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.
Partner: UNT Libraries Government Documents Department
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