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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 (sign… more
Date: December 20, 1961
Creator: Landis, D. A.
Partner: UNT Libraries Government Documents Department
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Ejection of Large Fragments in High-Energy Nuclear Reactions

Description: 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… more
Date: September 1, 1961
Creator: Crespo, V. P.
Partner: UNT Libraries Government Documents Department
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Kinetic Studies of the Reactions Occurring Between Tungsten and Gases at Low Pressure and High Temperatures

Description: 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. Th… more
Date: April 1, 1962
Creator: Anderson, H. U.
Partner: UNT Libraries Government Documents Department
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Heavy-Ion Elastic Scattering

Description: 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 e… more
Date: April 17, 1961
Creator: Alster, Jonas
Partner: UNT Libraries Government Documents Department
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Desulfurization of coal model compounds and coal liquids.

Description: Most US coals contain sulfur concentrations that prevent their being burned without some form of sulfur removal. Current coal-cleaning technology can only remove the fairly reactive pyritic (inorganic) and aliphatic (organic) sulfur. A process which removes the more refractory hetero-aromatic sulfur could substantially increase the amount of coal reserves amenable to chemical cleaning. Sodium metal dispersions convert refractor model compounds into lighter desulfurized products and non-volatile… more
Date: April 1, 1979
Creator: Wrathall, James Anthony & Peterson, Eugene E.
Partner: UNT Libraries Government Documents Department
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Nuclear Decay Schemes of Some of the Isotopes of Tantalum (Master's Thesis)

Description: This report discusses a nuclear spectroscopic study of the radiations resulting from the electron capture decay of Ta-176, Ta-177, and Ta-178, analyzing data of nuclear decay schemes.
Date: January 25, 1956
Creator: Felber, Frank Frederick, Jr.
Partner: UNT Libraries Government Documents Department
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The Method of Moments in Quantum Mechanics ; The [Pi]-Mesic Disintegration of the Deuteron

Description: The following report contains two reports to summarize a thesis: first, a report describing the classical moment techniques of Tchebycheff, Markov, and Stieltjes that have been applied to the problem of diagonalizing the Hamiltonian operator; and the second report describes an investigation of the higher-order corrections to the mesic disintegration of deuterons that is considered.
Date: March 18, 1957
Creator: Halpern, Francis R.
Partner: UNT Libraries Government Documents Department
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The Masses of Identified Positive Heavy Mesons

Description: The following report describes the charged secondary particles from all presently known decay modes of positive K mesons that have been identified, and the masses of the primaries measured by the momentum-range method.
Date: April 5, 1956
Creator: Peterson, James Ray
Partner: UNT Libraries Government Documents Department
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Alpha-Decay Studies in the Heavy Element Region

Description: Thesis describing a research conducted to extend observations on nuclear energy levels and how they effect the nucleus itself, and an investigation on the gamma rays associated for the even-even isotopes and to obtain additional data for the oddmass neclei in the hope that more regularities will become apparent for that class of nuclides.
Date: July 3, 1956
Creator: Hummel, John Philip
Partner: UNT Libraries Government Documents Department
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Analysis of Bevatron Tau Mesons

Description: The following document analyzes one hundred and seventy-seven bevatron tau mesons for Q value of the tau decay, tau spin and parity, and possible polarization effects.
Date: November 5, 1956
Creator: Haddock, Roy Phillip, 1928-
Partner: UNT Libraries Government Documents Department
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Analysis of the Interaction of 300-Mev Neutrons with Xenon

Description: 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. … more
Date: October 17, 1956
Creator: Morris, Richard Herbert, 1928-
Partner: UNT Libraries Government Documents Department
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Nuclear Interactions of Antiprotons (Thesis)

Description: This report follows the studies on the interactions of antiproton with ordinary matter.
Date: July 15, 1957
Creator: Keller, Donald Verne
Partner: UNT Libraries Government Documents Department
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Fission and Spallation Competition in Ra²²⁶, Th²³⁰, U²³⁵, and Np²³⁷

Description: This report follows the radiochemical study of fission and spallation products produced by bombardment of U-235 with 18- to 16-Mev helium ions and of the spallation products produced by 8- to 23-Mev deuteron bombardments of Np-237.
Date: July 1957
Creator: Vandenbosch, Robert
Partner: UNT Libraries Government Documents Department
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Electromagnetic dissociation of {sup 238}U in heavy-ion collisions at 120 MeV/A

Description: This thesis describes a measurement of the heavy-ion induced electromagnetic dissociation of a 120 MeV/A {sup 238}U beam incident on five targets: {sup 9}Be, {sup 27}Al, {sup nat}Cu, {sup nat}Ag, and {sup nat}U. Electromagnetic dissociation at this beam energy is essentially a two step process involving the excitation of a giant resonance followed by particle decay. At 120 MeV/A there is predicted to be a significant contribution of the giant quadrupole resonance to the EMD cross sections. The … more
Date: April 1, 1991
Creator: Justice, M. L.
Partner: UNT Libraries Government Documents Department
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Investigation of ultrafast photothermal surface expansion and diffusivity in GaAs via laser-induced dynamic gratings

Description: This thesis details the first direct ultrafast measurements of the dynamic thermal expansion of a surface and the temperature dependent surface thermal diffusivity using a two-color reflection transient grating technique. Studies were performed on p-type, n-type, and undoped GaAs(100) samples over a wide range of temperatures. By utilizing a 90 fs ultraviolet probe with visible excitation beams, the effects of interband saturation and carrier dynamics become negligible; thus lattice expansion d… more
Date: April 1, 1992
Creator: Pennington, D. M.
Partner: UNT Libraries Government Documents Department
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Laser trapping of {sup 21}Na atoms

Description: This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trap… more
Date: September 1, 1994
Creator: Lu, Zheng-Tian
Partner: UNT Libraries Government Documents Department
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Two-proton pickup studies with the (6Li,8B) reaction

Description: The (/sup 6/Li,/sup 8/B) reaction has been investigated on targets of /sup 26/Mg, /sup 24/Mg, /sup 16/O, /sup 13/C, /sup 12/C, /sup 11/B, /sup 10/B, and /sup 9/Be at a bombarding energy of 80.0 MeV, and on targets of /sup 16/O, /sup 12/C, /sup 9/Be, /sup 7/Li, and /sup 6/Li at a bombarding energy of 93.3 MeV. Only levels consistent with direct, single-step two-proton pickup reaction mechanisms were observed to be strongly populated. On T/sub z/ = 0 targets, the spectroscopic selectivity of this… more
Date: December 3, 1976
Creator: Weisenmiller, Robert Benjamin
Partner: UNT Libraries Government Documents Department
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Reaction of Tris(cyclopentadienyl)uranium compounds with amines, azides, and related ligands

Description: The trivalent uranium compound, (MeC{sub 5}H{sub 4}){sub 3}U(thf), serves as a one- or two-electron reducing agent towards azides, RN{sub 3}. These reactions produce either the uranium(IV) azide, (MeC{sub 5}H{sub 4}){sub 3}UN{sub 3}, or uranium(V) imides, (MeC{sub 5}H{sub 4}){sub 3}UNR. The role of steric and electronic effects upon this reaction has been investigated using several series of azides. For Me{sub 3}XN{sub 3}, the imides are produced when X = C or Si, both products are formed when … more
Date: December 1, 1989
Creator: Rosen, Robert Keith
Partner: UNT Libraries Government Documents Department
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Actinide Production in the Reaction of Heavy Ions withCurium-248

Description: Chemical experiments were performed to examine the usefulness of heavy ion transfer reactions in producing new, neutron-rich actinide nuclides. A general quasi-elastic to deep-inelastic mechanism is proposed, and the utility of this method as opposed to other methods (e.g. complete fusion) is discussed. The relative merits of various techniques of actinide target synthesis are discussed. A description is given of a target system designed to remove the large amounts of heat generated by the pass… more
Date: July 1, 1983
Creator: Moody, K. J.
Partner: UNT Libraries Government Documents Department
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OPTICAL DIFFERENCE FREQUENCY GENERATION OF FAR INFRARED RADIATION

Description: Three investigations of difference frequency generation (DFG) of far-infrared radiation by optical mixing are described: a theory of DFG by monochromatic, focused Gaussian pump laser beams, a theory of DFG by a picosecond pump laser pulse, and an experiment using ruby-pumped dye lasers. First, the theory of far-infrared generation by optical mixing of monochromatic, focused Gaussian beams in a uniaxial crystal is developed, taking into account the effects of diffraction, absorption, double refr… more
Date: July 1, 1977
Creator: Morris, J. R.
Partner: UNT Libraries Government Documents Department
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Spallation-Fission Competition in Neptunium Compound Systems. Decay-Scheme Studies

Description: 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,… more
Date: October 1, 1958
Creator: Lessler, R. M.
Partner: UNT Libraries Government Documents Department
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The Kinetics of the Complexing of Ferric Ion by Thiocyanate and Chloride Ions

Description: An apparatus for rapidly mixing two solutions and recording the light absorption, which was developed by Connick and Below, has been modified. The mixing characteristics were studied and models were developed in an attempt to umder stand the observed mixing phenomena. The apparatus was applied to a study of the kinetics of the reactions Fe/sup +++/ + SCN/sup -/ = FeSCN/sup ++/ and Fe/ sup +++/ Cl/sup -/ = FeCl/sup ++/ in aqueous solution, with both reactions having the forward rate law STAd(FeX… more
Date: December 1, 1957
Creator: Coppel, Claude Peter
Partner: UNT Libraries Government Documents Department
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The Radiation Chemistry of the Symmetrical Dichloroethylenes

Description: Purified, degassed samples of cis- and trans-1,2dichloroethylene were irradiated in glass cells with 48Mev helium ions at energy inputs up to 10/sup 21/ ev/cc. The principal volatile radiolysis products are acetylene, hydrogen chloride, chloroacetylene, vinyl chloride, hydrogen, and dichloroacetylene, in order of decreasing yield. The use of a mass spectrometer in conjunction with gas chromatography made possible the identification of several higher-boiling, or ''polymer,'' products as tetrachl… more
Date: July 1, 1958
Creator: Futrell, J. H.
Partner: UNT Libraries Government Documents Department
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