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On the Photofission Cross Sections Near Threshold of Nuclei in the Region of the Very Heary Elements

Description: Variations in the photofission cross section near ''threshold'' with initial kind of nucleus were investigated for seven spheroidal nuclei in the region of atomic numbers 90, 92, 93. The photofission cross sections at the two discrete energies 6.14 and 7.0 Mev were determined for the following even-even nuclide . Th/sup 232/, U/sup 234/, U/;sup 236/, and U/sup 238/; and also the odd- A nuclides. U/sup 233/, U/sup 235/ and Np/sup 237/. Nuclear excitation of the target nuclei was achieved via gam… more
Date: July 1, 1958
Creator: Clarke, K. M.
Partner: UNT Libraries Government Documents Department
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The Production of Neutral Hyperons by 5-Bev π$sup -$ Mesons

Description: Neutral hyperons produced by 5-Bev The effects of /sup -/ mesons incident on a large propane bubble chamber are analyzed in detail with respect to production cross sections and angular distributions of production and decays and the A lifetime is measured. The cross section for neutralhyperon (Y/sup 0/) production by the reaction The effects of /sup -/ + p 1100 deg C are Y/sup 0/ + K is 0.98 sintering time 0.16 mb. The cross section for carbon mpacting ( The effects of - + C 1100 deg C are Y/sup… more
Date: April 13, 1959
Creator: Hotz, D. F.
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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A Proposal for Determining the Electro-Magnetic Form Factor of the Pion

Description: The possibility of measuring the electromagnetic form factor of the pion by extrapolation of the cross section for e/sup -/ + p 1100 deg C are n + The effects of /sup +/ + e/sup -/ was investigated. The method is based on the existence of a pole in the electropionproduction scattering amplitude as a function of the invariant momentum-transfer of the nucleon. The residue of this pole is the pion form factor multiplied by a known coefficient. Since the pole lies slightly outside the physical regi… more
Date: February 1, 1959
Creator: Frazer, William Robert
Partner: UNT Libraries Government Documents Department
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On the Three-Dimensional Instability of Laminar Boundary Layers on Concave Walls

Description: Memorandum presenting a study of the stability of laminar boundary layer profiles on slightly curved walls relative to small disturbances, in the shape of vortices, whose axes are parallel to the principal direction of flow. The result in an eigenvalue problem by which, for a given undisturbed flow at a prescribed wall, the amplification or decay is computed for each Reynolds number and each vortex thickness.
Date: June 1954
Creator: Görtler, H.
Partner: UNT Libraries Government Documents Department
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Measurement of Beam Current in the Bevatron by Induced Voltages

Description: 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… more
Date: October 28, 1957
Creator: Lavrischeff, J. T.
Partner: UNT Libraries Government Documents Department
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A Study of the Effects of Elevated Temperatures on the Growth and Inheritance of Saccharomyces Cerevisiae

Description: A comparative study was made of the growth of yeast in various media at the optimum temperature (30 ) and at supraoptimum temperatures. It was found that at elevated temperatures there is a decrease in the ability of yeast to grow, which may be alleviated by increasing the percentage of yeast extract in the medium, adding oleic acid to the medium, or using an inoculum of cells that have previously been grown at the elevated temperature. Because of these findings, it is believed that growth at e… more
Date: November 1, 1958
Creator: Sherman, F.
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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Studies Relating to the Structure of Aluminum Hydride

Description: The object of the work was to determine the molecular structure of AlH/ sub 3/, using the techniques of nuclear spin resonance.'' Attempts to prepare ether-free AlH/sub 3/ that were unsuccessful are described. Also it was not possible to observe the deuterium signal in AlH/sub 3/. It was possible, by the use of the proton signal of the ether in AlH/sub 3/, to obtain the nuclear spin resonance absorption curve for AlH/sub 3/ by subtracting out the contributions of the ether protons to the resona… more
Date: December 16, 1957
Creator: Nickerson, R. F.
Partner: UNT Libraries Government Documents Department
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Independent Yields of Isomeric Pairs in Nuclear Reactions

Description: The Cd/sup 115m/ and Cd/sup 115/ isomers produced in 12- to 340Mev proton bombardments of U/sup 238/ were isolated by radiochemical methods. The cumulative yield ratios of Cd/sup 115/Cd/sup 115m/Cd/ were determined. In the 45- Mev heliumion flssion of uranium, an estimation of the independentyield ratio of Pm/sup 148/ (5.3-day) to Pm/sup 148/ (43-day) was made. In the deuteron fission of uranium at about 20 Mevs an estimate of the independent-yield ratio of Nb/sup 95m/ to the total niobium of m… more
Date: April 1, 1959
Creator: Bailey, S. M.
Partner: UNT Libraries Government Documents Department
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Electric Conduction in an Oil-Pumped Vacuum System

Description: The leakage of electricity aoross a vacuum space in an electrostatic generator which employs a mixture of Sr/sup 90/ and Y/sup 90/ as the source of charging current was investigated. The vacuum is obtained by means of an oil pump. The leakage was shown to consist of a flow of positive and negative particles between the anode and the cathode. The positive particles were found to be primarily organic ions produced in a layer of oil on the surface of the anode. The negative particles were shown to… more
Date: May 1, 1956
Creator: Bryant, Ernest A.
Partner: UNT Libraries Government Documents Department
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[Chemistry Thesis] Part 1: The Spectra of Some Aliphatic Aldehydes and Their Monodeutero Derivatives,

Description: 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… more
Date: October 1, 1958
Creator: Worden, Earl Fremont, Jr.
Partner: UNT Libraries Government Documents Department
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Angular Distribution of Photopions From Hydrogen

Description: ABS>An accurate measurement of the differential cross section for the photoproduction of positive pions was made at the Berkeley synchrotron, for photon energies of 280 and 290 Mev. The mesons were produced in a thin-walled liquid hydrogen target, and the meson detection apparatus utilized the characteristic pi -- mu decay of the meson. The measurements were done in two steps, from 0 to 50 deg with equipment specifically designed to reduce a very high positron background, and from 30 to 160 deg… more
Date: July 1, 1958
Creator: Knapp, E. A.
Partner: UNT Libraries Government Documents Department
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