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Use of Analog Computers for Simulating the Movement of Isotopes in Ecological Systems (open access)

Use of Analog Computers for Simulating the Movement of Isotopes in Ecological Systems

None
Date: January 24, 1962
Creator: Neel, R. B. & Olson, J. S.
System: The UNT Digital Library
A Study of the Kinetic and Mechanical Properties of a Stabilized Beta Phase Plutonium Alloy (open access)

A Study of the Kinetic and Mechanical Properties of a Stabilized Beta Phase Plutonium Alloy

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 …
Date: January 1, 1962
Creator: Taylor, J. M.
System: The UNT Digital Library
Low Temperature Thermoluminescence of Gamma Irradiated Potassium Dihydrogen Phosphate (open access)

Low Temperature Thermoluminescence of Gamma Irradiated Potassium Dihydrogen Phosphate

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/ …
Date: October 19, 1962
Creator: Sims, T. M.
System: The UNT Digital Library
The Specific Heat of Dysprosium Metal Between 0.4 and 4 K (open access)

The Specific Heat of Dysprosium Metal Between 0.4 and 4 K

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.
System: The UNT Digital Library
Kinetic Studies of the Reactions Occurring Between Tungsten and Gases at Low Pressure and High Temperatures (open access)

Kinetic Studies of the Reactions Occurring Between Tungsten and Gases at Low Pressure and High Temperatures

Oxygen, nitrogen, and nitric oxide gases were passed through a system consisting of a tungsten filament, an ion gauge, and a mass spectrometer. The ion gauge recorded total pressures and the spectrometer recorded partlal pressures of O/sub 2/, N/sub 2/, NO, CO, COa, and H/sub 2/O. From the way these pressures changed with filamert temperature, the rates of conversion of O/sub 2/ to volatile tungsten oxides and O, and of NO to volatile tungsten oxides N/sub 2/ , O/sub 2/, and O were computed. The time rate of resistance change in the filament was used to compute the rate of conversion of tungsten to tungsten oxides. The filament temperatures ranged from 1950 through 2600 deg K and gas pressures ranged from 10/sup -8/ to 10/sup -6/ atm. For the tungsten-oxygen reaction, the rates of tungsten and oxygen loss were found to depend upon oxygen atom concentration on the surface. The rate of oxide power, depending upon the concentration of oxygen atoms on the surface. The reaction rate at constant oxygen pressure decreases with increasing temperature. For calculational purposes, the tungsten oxygen gas moleeules were assumed to be WO/sub 3/ only, though WO/sub 2/ and WO are other possible products. The …
Date: April 1, 1962
Creator: Anderson, H. U.
System: The UNT Digital Library
A Method for Estimating the Heat of Formation and Free Energy of Formation of Inorganic Compounds (open access)

A Method for Estimating the Heat of Formation and Free Energy of Formation of Inorganic Compounds

None
Date: August 1, 1962
Creator: Wilcox, D. E.
System: The UNT Digital Library
The Moderation of Neutrons in Non-Multiplying Infinite Homogeneous Media. (open access)

The Moderation of Neutrons in Non-Multiplying Infinite Homogeneous Media.

Submitted to Univ. of Minnesota, Minneapolis. The gas model of neutron thermalization for a general moderator mass was studied by formulating the thermalization process as an integral equation. The relation of the model to the slowing-down theory was investigated. A discussion of the theory of scattering cross sections for neutrons is presented. The Wigner-Wilkins model was considered for moderator atoms of the same mass as the neutron. The analysis was extended to the case of a gaseous moderator with atoms of general mass. (M.C.G.)
Date: January 1, 1962
Creator: Min, K.
System: The UNT Digital Library
The Angular Distribution of Fission Fragments From the Fast Neutron-Induced Fission of U-234 (open access)

The Angular Distribution of Fission Fragments From the Fast Neutron-Induced Fission of U-234

Submitted to Univ. of Tennessee, Knoxville. The fast neutron-induced fission cross section of U/sup 234/ was measured from threshold to 4-Mev neutron energy. A maximum of 1.26 barns was found at 850 kev followed by a minimum of 1.10 barns at 8050 kev. The angular ani-sotropy of the fragment distribution was measured for neutron energies from 400 kev to 4 Mev. Extrema in the ratio sigma /sub f//( sigma /sub f(90 deg ) were found at 500, 850, and 1050 kev; the distribution at 500 kev showing a maximum in the direction normal to the beam (side-wise peaking) while that at 850 kev showed a maximum along the beam direction. The distribution at 8050 kev showed forward peaking but to a lesser extent than for energies immediately higher or lower. The behavior was analyzed according to the theories of Bohr and Wheeler. The dip in cross section between 850 and 1050 kev is consistent with the suggestion of Wheeler that neutron competition in the decay of the compound nucleus enters with increased strength in this area. Vibration-rotational levels in U/sup 234/ beginning at 790 kev are known to exist and inelastic neutron scattering to these levels serves to depress the …
Date: August 27, 1962
Creator: Lamphere, R. W.
System: The UNT Digital Library
The Relationship between Selected Criteria and Actual Practices of Counselors and Visiting Teachers in a Metropolitan Area (open access)

The Relationship between Selected Criteria and Actual Practices of Counselors and Visiting Teachers in a Metropolitan Area

This study was initiated to determine the soundness of certain phases of the counseling and visiting teacher program in a selected school system of a metropolitan area. It was believed that investigation of those programs would prove to be of significant value to those individuals who were in charge of the guidance programs in those schools, and that ultimately the full benefits of these investigations would be received by the students.
Date: August 1962
Creator: Wotherspoon, Clark David, 1914-
System: The UNT Digital Library
The Effects of Skill-Builder Controlled Reader Training in Facilitating Skill Development in College Typewriting (open access)

The Effects of Skill-Builder Controlled Reader Training in Facilitating Skill Development in College Typewriting

The problem of the study was to determine the effects of student use of Skill-Builder Controlled Reader training in facilitating skill development in beginning and intermediate typewriting classes at the college level.
Date: August 1962
Creator: Johnson, Margaret Higgins, 1920-
System: The UNT Digital Library
Differential Distributions of Neutrons in Inelastic π$sup -$P Interactions at 374, 417, and 454 Mev (open access)

Differential Distributions of Neutrons in Inelastic π$sup -$P Interactions at 374, 417, and 454 Mev

The inelastic interactions of negative pi mesons with protons at 374, 417, and 454 Mev incident pi kinetic energy are studied by measuring the differential distributions of finalstate neutrons. The pi source is an internal target of the Berkeley 184-inch synchrocyclotron. A magnetic beamtransport system momentum-anaiyzes and focuses the pi beam at a liquid hydrogen target located in an adjacent shielded experimental area. The time-of- flight distribution of neutral particles is measured at various laboratorysystem angles between 10 and 65 deg. Neutral particles are detected by observing the charged products of their interactions in plastic scintillator. The time-of- flight information is determined electronically by time-to-height conversion and pulse-height analysis. The time resolution of the total system is 1.0 nsec. Detected neutral particles accompanied by charged particles are separated by the electronic system from those not accompanied by charged particles. Analysis presuming the principal inelastic reactions to be pi /sup -/p yields pi /sup +/ pi /sup -/n and pi /sup -/p yields pi /sup 0/ pi /sup 0/n separates the time-of-flight spectra into gamma rays, neutrons from the reaction pi /sup -/p yields pi /sup 0/n, and inelastic neutrons. Calculated values of the neutron- detection efficiency are used in the …
Date: November 15, 1962
Creator: Kurz, R. J.
System: The UNT Digital Library
Nuclear Reactions Induced by Pions and Protons (open access)

Nuclear Reactions Induced by Pions and Protons

Effects due to elementary particle-like collisions within nuclear matter have been observed in several nuclear reactions caused by pions and protons. Simple nuclear reactions of the form ZA(a,an)Z/sup A-1/ and Z/sup A/(a,ap)(Z-1)/ sup A-1/ have excitation functions that are sensitive to changes in the elementary-particle cross sections. The excitation function for the reaction C/ sup 12/( pi /sup -/, pi /sup -/n)C/sup 11/ is measure d from 53 to 1610 Mev by bombarding targets of plastic scintillator with pions. The intensity of the pion beam is monitored with a two-counter telescope and 40 Mc scaling system. The scintillator target is mounted on a phototube and becomes the detector for the carbon-11 positron activity. Corrections are made for muon contamination in the beam, coincidence losses in the monitor system, carbon-11 activity produced by stray background at the accelerator, carbon-1l activity produced by secondaries in the target, and the efficiency of the carbon-11 detection system. The C/sup 12/( pi /sup -/, pi /sup -/n)C/sup 11/ cross sections rise to a peak of abo ut 70 mb at 190 Mev, that corresponds to the resonance in freeparticle pi /sup -/n scattering at 190 Mev. Calculations based on a knock-on'' collision mechanism and sharp-cutoff …
Date: November 27, 1962
Creator: Reeder, P. L.
System: The UNT Digital Library
Two Topics in Pion Physics. [Part] 1. Photoproduction of Neutral Pions From Complex Nuclei and the Pair-Correlation Function. [Part] 2. The Relative Rate of Absorption of Negative Pions in Hydrogen and Deuterium (open access)

Two Topics in Pion Physics. [Part] 1. Photoproduction of Neutral Pions From Complex Nuclei and the Pair-Correlation Function. [Part] 2. The Relative Rate of Absorption of Negative Pions in Hydrogen and Deuterium

A simple theory of the photoproduction of pi /sup 0/ mesons from complex nuclei based on the impulse and closure approximation is studied. The theory is compared with an experiment of Goodwin, Anderson, and Kenney that shows the dependence of the number of decay gammas from pi /sup 0/ mesons photo- produced from various nuclei as a function of the atomic number at 45, 90, and 135 degrees for incident photon energies from threshold to 350 Mev. The dependence measured near threshold and at 45 degrees does not agree with the simple theory nor is it consistent with partial elastic production. By a method of Placzek and Wick the corrections to the simple theory are estimated, and found to be large near threshold. These corrections may explain the discrepancy between the theory and the experimental results. No information about the nuclear-pair correlation function is obtained. The impulse approximation is used to calculate the relative ratio of the radiative absorption rate of pi /sup -/ mesons absorbed in hydrogen and deuterium from an atomic s state. The calculated value of the ratio T = R( pi /sup -/ + d yields 2n + gamma )/R( pi /sup -/ + p yields …
Date: August 13, 1962
Creator: Traxler, R. H.
System: The UNT Digital Library
Atomic Capture of $mu$$sup -$ Mesons in Chemical Compounds and The "Fermiteller Z Law" (open access)

Atomic Capture of $mu$$sup -$ Mesons in Chemical Compounds and The "Fermiteller Z Law"

Experimental studies of the relative atomic mu --meson capture probabilities in the constituents of chemical compounds are described. Fermi and Teller had predicted that the atomic-capture probability is proportional to the nuclear charge of the atomic species weighted by its atomic concentration. This is sometimes referred to as the Fermi-Teller Z law.'' Previous experiments indicated no clear systematics to this capture process, and there are conflicts between the results of several measurements made with the same or similar compounds. In these experiments the capturing atom was identified by detection of either mesic x rays or decay electrons from mu /sup -/ mesons bound in the mesic K shell in the atomic species, In these experiments oxides and sulfides of some medium- and high-Z elements as well as two metallic solutions were used, and a nuclear capture product (neutron) rather than the decay electrons was detected. Results show that among the substances examIned, namely CuO, Sb/sub 2/O/sub 3, PbO, CuS, Sb/sub 2/S/sub 3/, PbS AgLi, and CuAu, the Z law'' behavior is not indicated either in insulators or in metals, although in all cases there is a preference for capturing in the atom of higher Z. If the atomic-capture probability is …
Date: August 20, 1962
Creator: Baijal, J. S.
System: The UNT Digital Library
String Septet (open access)

String Septet

A thesis about the String Septet. The author explains that it deals with problems concerned in the reconciliation of contemporary aesthetics with extensions of romantic harmony, classical and pre-classical form, classical figuration and ornamentation, and contrapuntal organization.
Date: August 1962
Creator: Hughes, Phillip Ralph B. M.
System: The UNT Digital Library
Downflow Boiling of n-Butanol in a Uniformly Heated Tube (open access)

Downflow Boiling of n-Butanol in a Uniformly Heated Tube

None
Date: October 29, 1962
Creator: Somerville, G. F.
System: The UNT Digital Library
Cycling of Cesium-134 in White Oak Trees on Sites of Contrasting Soil Type and Moisture (open access)

Cycling of Cesium-134 in White Oak Trees on Sites of Contrasting Soil Type and Moisture

The cycle of cesium-134 (2 mu c) in white oak trees on four sites differing soil type and moisture was followed. Gains, losses, and transfers were estimated by sampling from inoculated trees, understory, litter, and soil. With rapid translocation into leaves from initial trunk inoculations in the spring, white oak leaves contained 10/sup 5/ to 10/sup 6/ dpm per g dry weight by early June. This represented a total transfer of about 40% of the original input. From rains, loss from leaves continued throughout the growing season until September, by which time a total loss of 15% of the observed maximum concentration in leaves had occurred. Approximately 70% of this rain-induced loss reached the mineral soil by September, the remainder located in litter and understory vegetation. Radiocesium transferred from trees via annual leaf fall was two times greater than the quantity exported by rain. With subsequent leaching over the winter months, the litter lost about half of its radiocesium to the mineral soil. Soils on wet sites had significantly greater percentages at lower depths down to 12 in. However, 92% of the total soil radiocesium remained in the top 4 in. on year and seven months after tree inoculation. A …
Date: November 1, 1962
Creator: Witherspoon, J. P., Jr.; Auerbach, S. I. & Olson, J. S.
System: The UNT Digital Library
On the Nature of Dispersed Particle Strengthening at Low Temperatures (open access)

On the Nature of Dispersed Particle Strengthening at Low Temperatures

Polycrystalline aluminum-copper alloys containing 4 and 5% copper were given heat treatments designed to develop dispersions of Al/sub 2/Cu precipitate particles of various sizes and distributions. Tensile tests were performed on the dispersion hardened alloys at 4.2, 77, 90 and 114 deg K to determine the strain rate and temperature dependence of the flow stress. The intersection analysis of the tensile data showed that the dispersed particles significantly increase the average effective forest dislocation density produced for a given amount of strain. The increased dislocation density was found to be in qualitative agreement with selected electron-microscope observations of the deformed structure of the alloys. Estimates of contributions to the flow stress arising from effects coincident with the intersection of dislocations and those associated with the build-up of long range stress fields were made. The major strengthening contribution of the dispersed particles during plastic deformation is shown to be due to an increase in the dislocation density associated with relatively high density tangles of dislocations observed to be localized near particles and groups of particles. (auth)
Date: August 1, 1962
Creator: Mitchell, J. B.
System: The UNT Digital Library
Planning, Scheduling, and Expediting Engineering Projects With the Aid of Electronic Computers (open access)

Planning, Scheduling, and Expediting Engineering Projects With the Aid of Electronic Computers

>Submitted to Illinois Inst. of Tech., Chicago. Two methods for planning, scheduling, and monitoring engineering and scientific research and development projects are discussed. They are the Critical Path Method and PERT. The specific development and implementation of network analysis techniques being used in the construction of the Zero Gradient Synchrotron are described. The historical development of the Critical Path Method and PERT is outlined. Network diagrams, numbering network diagrams, activity duration times, mathematical evaluation of the network, government and industrial use of PERT and CPM, and applications of network analysis techniques are discussed. (M.C.G.)
Date: May 1, 1962
Creator: Pollock, J. C.
System: The UNT Digital Library
Matrix Isolation Studies of High-Temperature Species Group II Chlorides (open access)

Matrix Isolation Studies of High-Temperature Species Group II Chlorides

A matrix isolation technique for the investigation of infrared absorption spectra of molecules of hightemperature species trapped in a pseudo- gas phase'' is described. The spectra of the dichlorides of zinc, cadmium, and mercury in argon, krypton, and xenon matrices are reported. Presence in the gas phase of dimers of zinc chloride and mercuric chloride is noted. An absorption band, previously reported as due to the degenerate bending motion of zinc chloride, is attributed to zinc dimer. (auth)
Date: September 13, 1962
Creator: McNamee, R. W., Jr.
System: The UNT Digital Library
Direct Contact Condensation With Two Immiscible Fluids (open access)

Direct Contact Condensation With Two Immiscible Fluids

87p. The theory, design techniques, and relative economics are presented for three basically different direct-contact condensation processes involving fluids whose condensed phases are immiscible. In the specific system developed for the study, Aroclor 1248 (Monsanto Chemical Corporation) and steam were used. The processes investigated include the injection, and the induction of steam into a highvelocity stream of Aroclor in the throat section of a Venturi. The bubbling of steam into a low-velocity stream of Aroclor, using a packed tower to artificially increase the surface of contact was also investigated. The induction, injection, pressure drop, and heat-transfer characteristics of a Venturi in direct-contact condensation service were experimentally investigated, and empirical correlations for the performance of the unit are included. The performance of a direct-injection device was also experimentally determined, and correlations obtained. A discussion is included concerning the theoretical development of relations which are used to predict the performance of packed towers in direct-contact condensation service. (auth)
Date: June 29, 1962
Creator: Lackey, D. L.
System: The UNT Digital Library
Study of Pion-Pion Scattering from the Reaction $pi$$sup +$ + p $Yields$ $pi$$sup +$ + $pi$$sup +$ + n AT 1.25 AND 1.75 Bev/c (open access)

Study of Pion-Pion Scattering from the Reaction $pi$$sup +$ + p $Yields$ $pi$$sup +$ + $pi$$sup +$ + n AT 1.25 AND 1.75 Bev/c

The equipment and procedure used in measuring the distribution of energy and angle of recoil of neutrons from the reaction pi /sup +/ + p yields pi / sup +/ + pi /sup +/ + n for incident pion mome nta of 1.25 and 1.75 Bev/c are explained. Utilization of the plastic scintillator detectors is given particular attention. Data on the cross section for pion-pion scattering are presented and analyzed. (22 references.) (D.C.W.)
Date: October 31, 1962
Creator: Auerbach, L. B.
System: The UNT Digital Library
The Mechanism of the Martensite Burst Transformation in Single Crystals of Iron Containing 31.7 Per Cent Nickel (open access)

The Mechanism of the Martensite Burst Transformation in Single Crystals of Iron Containing 31.7 Per Cent Nickel

The martensite burst transformation was studied in single crystals of iron containing 31.7% nickel. It was found that the morphology of the transformation was greatly simplified in crystals that had heen strained plastically prior to transformation. This simplification made possible detaiied crystallographic studies of the morphology of the transformation. These studies showed that the autocatalysis responsible for the burst transformation had its origin in a mechanical stimulation (coupling) between certain variants of the habit plane that were geometrically oriented such that the stress induced by transformation on one aided transformation on the others. In both strained and unstrained crystals, the most effective mechanical autocatalysis was observed to be between groups of four nearly parallel pianes whose poles clustered about common ( 110) directions. In the transformation of strained crystals, the operation of certain of these groups was favored. These were the groups whose planes were nearly perpendicular to the active slip plane, but did not include the group whose poles clustered about the Burger's vector of the active slip system. This behavior was taken to be a consequence of the anisotropic substructure introduced during deformation. Because of the enhanced transformation by certain groups in strained crystals, the frequency of secondary …
Date: September 1, 1962
Creator: Bokros, J. C.
System: The UNT Digital Library
Permeation of Helium Into Vacuum Tubes (open access)

Permeation of Helium Into Vacuum Tubes

None
Date: May 1, 1962
Creator: Rode, J. J.
System: The UNT Digital Library