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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
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
[Chemistry Thesis] Part 2: High Intensity Light Sources (open access)

[Chemistry Thesis] Part 2: High Intensity Light Sources

A stable carbon arc operated in controlled atmosphere is described. The arc was designed to serve as a light source during lifetime studies of the B/sup 2/ SIGMA state of the CN molecule. The CN radiation from the plasma of the arc was investigated and found to have a brightness temperature of 5500 icient laborato K at lambda 3883 A. This is considerably higher than an estimate of the value required for lifetime measurements. The stability of the carbon arc under various conditions is discussed. For successful lifetime measurements, the light source employed must have a high brightness temperature (intensity). A method for the determination of the brightness temperature of a light source at a specific wave length is described. The method was used for determining the brightness temperatures of some available light sources. Sodium, thallium, and mercury discharge lamps, a medium-pressure mercury arc lamp, and the carbon arc were studied. (auth)
Date: October 9, 1958
Creator: Worden, Earl Fremont, Jr.
System: The UNT Digital Library
[Chemistry Thesis] Part 1: The Spectra of Some Aliphatic Aldehydes and Their Monodeutero Derivatives, (open access)

[Chemistry Thesis] Part 1: The Spectra of Some Aliphatic Aldehydes and Their Monodeutero Derivatives,

BS>An investigation of the infrared and near-ultraviolet spectra of three aliphatic aldchydes and their monodeutero derivatives is described. The infrared spectra of the acetaldehydes (CH/sub 3/CHO and CH/sub 3/CDO) were in agreement with work reported recently. A few new bands are reported and discussed. The infrared spectra of C/sub 2/H/sub 5/CHO, C/sub 2/H/sub 5/CDO, C/ sub 3/H/sub 7/CHO, and C/sub 3/H/sub 7/CDO at 450 to 4000 cm/sup -1/ were observed, and an assignment of the observed bands was made. The weak absorption of the aliphatic aldehydes which extends from lambda 3500 A to lambda 2300 A was investigated. The strength of the absorption (f-value) is decreased by deuterium substitution at the aldehyde CHO group. The decrease in the f-value can be accounted for by the theory of vibrationally induced electronic transitions. The effect of isotopic substitution on the intensity of symmetry- allowed as well as synnmetryforbidden (vibrationally allowed) electronic transitions in polyatomic molecules is discussed. (auth)
Date: October 1, 1958
Creator: Worden, Earl Fremont, Jr.
System: The UNT Digital Library
Spallation-Fission Competition in Neptunium Compound Systems. Decay-Scheme Studies (open access)

Spallation-Fission Competition in Neptunium Compound Systems. Decay-Scheme Studies

The results of a radiochemical study of fission and spallation products induced in U/sup 234/, U/sup 235/, and U/sup 236 and spallation products induced in U/sup 238/ by deuterons of less than 24 Mev are presented. The (d,n) reactions are interpreted as the result of direct interactions between the deuteron and the target nuclei, while the (d,n) reactions are thought to be taking place primarily by compound-nucleus mechanisms. A method for predicting the peak values of the cross section for (d,xn) and ( alpha ,xn) reactions on uranium and plutonium isotopes is given for x = 2, 3, or 4. The peak-to-valley ratios of the fission-yield curves for U/sup 234, U/sup 235/, U/sup 236/, and U/ sup 238/ bombarded with deuterons of energies of about 23 Mev were studied, and no significant differences were found. Excitation functions for the (d, gamma ) reactions of U/sup 234/, U/sup 236/, and U/sup 238/ rise to a maximum of about a millibarn at a bombarding energy between 15 and 20 Mev. The results of these measurements are seen to be consistent with the excitation functions for (p, gamma ) and ( alpha , gamma ) reactions. The 60minute neptunium activity which had previously …
Date: October 1, 1958
Creator: Lessler, R. M.
System: The UNT Digital Library
Measurement of Beam Current in the Bevatron by Induced Voltages (open access)

Measurement of Beam Current in the Bevatron by Induced Voltages

The Bevatron uses a system of electrodes through which the internal proton beam passes in order to continuously measure the magnitude and radial position of the beam. The bunched circulating beam induces a periodic voltage on the electrodes. This signal is amplified and displayed on an oscilloscope and also converted to direct current for operation of a recorder. Two types of electrode systems are used. The first is a large hollow box to provide beam magnitude signals for specialized monitoring and for primary calibration. The second system consists of two sets of smaller electrodes. One set provides beam radial-position information for tracking control, and the other provides beam magnitude information for magnitude control and for general distribution to experimenters associated with the Bevatron. A telemetering radio link is used to relay beam information to those in other areas. Problems associated with handling the beam signal are discussed, and the design principles involved in detection, amplification, and isolation of the signal are described. Calibration techniques, signal distribution facilities, and control features are also given. The systems described are stable and provide the desired information with a minimum of maintenance and operational difficulty. (auth)
Date: October 28, 1957
Creator: Lavrischeff, J. T.
System: The UNT Digital Library
Analysis of the Interaction of 300-Mev Neutrons with Xenon (open access)

Analysis of the Interaction of 300-Mev Neutrons with Xenon

Abstract: And investigation of the interactions between 300-Mev neutrons and xenon was made by means of a cloud chamber in a pulsed magnetic field of 21,700 gauss placed in the neutron beam of the 184-inch Berkeley cyclotron. Eighty-seven negative pion events and 257 other stars were analyzed. In addition an experimental check was made on the energy of the incoming neutrons. Classification, identification, and angular and energy distributions of prongs associated with all events are presented. Interpretations of results are given.
Date: October 17, 1956
Creator: Morris, Richard Herbert, 1928-
System: The UNT Digital Library
ANALYSIS OF THE INTERACTION OF 300-Mev NEUTRONS WITH XENON (open access)

ANALYSIS OF THE INTERACTION OF 300-Mev NEUTRONS WITH XENON

An investigation of the interactions between 300-Mev neutrons and xenon was made by means of a cloud chamber in a pulsed magnetic field of 21,700 gauss placed in the neutron beam of the 184-inch Berkeley cyclotron. Eighty-seven negative pion events and 257 other stars were analyzed. In addition an experimental check was made on the energy of the incoming neutrons. Classification, identification, and angular and energy distributions of prongs associated with all events are presented. Interpretations of results are given.
Date: October 17, 1956
Creator: Morris, Richard Herbert.
System: The UNT Digital Library
Low Level Polonium Determination of Tissue and Urine (open access)

Low Level Polonium Determination of Tissue and Urine

None
Date: October 1, 1956
Creator: Black, S. C.
System: The UNT Digital Library
Capacity Factors in the Performance of Perforated Plate Distillation Columns (open access)

Capacity Factors in the Performance of Perforated Plate Distillation Columns

From abstract: "A study of factors affecting the vapor handling capacity of perforated plate liquid-vapor contacting columns. Vapor phase pressure drop across plates, liquid entrainment upward from plate to plate, and plate stability were investigated as functions of operational and geometric column parameters."
Date: October 1954
Creator: Hunt, Charles d'Ancona, 1924-
System: The UNT Digital Library