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AN INFORMATION STORAGE AND RETRIEVAL SYSTEM FOR IRRADIATION EFFECTS IN METALS

Description: An information storage and retrieval system (PIC) was developed, utilizing the IBM 7090 computer, for handling data pertaining to the effects of neutron irradiation on metals. The input includes a reference identification, an appropriate abstract or extract summarizing the article, code identification parameters analogous to those used by the ASM-SLA Literature Classification System, and special codes identifying relevant irradiation and testing parameters. The output contains the same data plu… more
Date: August 15, 1963
Creator: Bush, S. H.
Partner: UNT Libraries Government Documents Department
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Physics Performance of the EBWE in Its Zero to 100 Mw Operation

Description: The distribution of fuel elements in the EBWR core is described. Spike elements with boron steel strips were provided in the core for burnup allowance. A calibration of the control rod system with Zircaloy followers was made. Void coefficient measurements were made for two different H/sub 3/BO/sub 3/ concentrations. Power runs were made, and reactivity loss vs. power characteristic was obtained. Steam remaining in the core, or carryunder,'' was indicated. Some of the spikes were remov… more
Date: June 1963
Creator: Iskenderian, H. P.
Partner: UNT Libraries Government Documents Department
open access

Analysis of Vanadium in Milk Powder by Neutron Activation Analysis Using a Rapid Radiochemical Separation of 3.77-Minute Vanadium-52

Description: A procedure is described for the activation determination of V in powdered milk using 3.77-min V/sup 52/. The quantity of V in the sample is obtained by comparing the V/sup 52/ radioactivity found in the test sample with the V/sup 52/ radioactivity in a V comparator sample that is treated in the same manner as the test sample. The procedure can also be used for the determination of V in a variety of materials. (P.C.H.)
Date: November 15, 1963
Creator: Molinski, V. J.; Wahl, W. H. & Strain, W. H.
Partner: UNT Libraries Government Documents Department
open access

BETA-RAY SPECTROMETER WITH REDUCED SPHERICAL ABERRATION

Description: Modern {beta}-ray spectrometers are based upon the concept, first introduced by Svartholm and Siegbahn in 1946, of focusing in both the radial and vertical directions. The theory of axially symmetric devices has been carefully studied by a large number of workers, culminating in the analysis, in 1956, of Lee-Whiting and Taylor. These last authors calculate aberrations through the sixth order and show that by appropriate choice of the magnetic field a spectrometer can be designed with a relative… more
Date: February 4, 1963
Creator: Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
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LONGITUDINAL RESISTIVE INSTABILITIES OF INTENSE COASTING BEAMS IN PARTICLE ACCELERATORS

Description: The longitudinal electromagnetic interaction of an intense coasting beam with itself, including the effect of a resistive vacuum tank, is investigated theoretically. It is shown that even in the range where the particle frequency is an increasing function of particle energy, the beam can be longitudinally unstable due to the resistivity of the vacuum tank walls. In the absence of frequency spread in the unperturbed beam the beam is shown to be always unstable against longitudinal bunching with … more
Date: October 23, 1963
Creator: Neil, V. Kelvin & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
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BREMSSTRAHLUNG IN A DENSE PLASMA

Description: The bremsstrahlung emitted by an electron scattered in a Coulomb field was first calculated by Bethe and Heitler. The total cross section for production of photons with wave number between k and k + dk by a nonrelativistic electron of kinetic energy {epsilon} is d{sigma}/dk dk = 16/3 Z{sup 2}r{sub 0}{sup 2} (e{sup 2}/hc) (mc{sup 2}/{epsilon})log ({radical} {epsilon}/hck + {radical} {epsilon}/hck -1) dk/k, where Ze is the charge of the (heavy) ion, and r{sub 0} is the classical electron radius. … more
Date: January 15, 1963
Creator: Stack, John D. & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
open access

CORRELATION EFFECTS IN MANY FERMION SYSTEMS: MULTIPLE PARTICLE EXCITATION EXPANSION

Description: The ground-state wave function and energy of a finite system of interacting fermions are expanded in terms of multiple-particle excitations on an uncorrelated zero-order state. The resulting set of coupled equations constitutes a systematic variational generalization of Hartree-Fock theory. Comparison is made with many-body perturbation theory and it is shown that to any order the theory incorporates an infinite number of perturbation theory terms. Solutions of the equations for ground-state at… more
Date: July 1, 1963
Creator: Kelly, Hugh P. & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
open access

THE LIFETIME OF BACTERIAL MESSENGER RNA

Description: Puromycin, an inhibitor of protein synthesis, appears to act as an inhibitor at additional sites during the induction of {beta}-galactosidase synthesis. No inhibition of the reactions proceeding during the first 20 seconds of induction was observed, but puromycin seems to prevent the accumulation of messenger RNA during the period between 20 seconds and the first appearance of enzyme activity after 3 minutes. When cells from a stationary culture are placed in fresh medium containing inducer for… more
Date: December 1, 1963
Creator: Moses, V. & Calvin, M.
Partner: UNT Libraries Government Documents Department
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OPTICAL PROPERTIES OF CHROMOPHORE-MACROMOLECULE COMPLEXES:ABSORPTION AND FLUORESCENCE OF ACEIDINE DIES BOUND TO POLYPHOSPHATES ANDDNA

Description: Dye-macromolecule complexes provide good models for the study of the effects of coupling between chromophores. In addition to modifications of the visible and UV absorption spectra of the dyes at small interchromophore distances, very efficient energy transfer has been demonstrated at longer distances. The probability of nonradiative transition increases with the number of excitation transfers so that an array of oscillators close to one another becomes nonfluorescent. The insertion of a dye mo… more
Date: August 1, 1963
Creator: Weill, G. & Calvin, M.
Partner: UNT Libraries Government Documents Department
open access

Cryogenic targets for electron scattering

Description: Over the past few years we have developed a system which allows several different liquid hydrogen and liquid deuterium targets to be placed in the electron beam of the Stanford Mark III accelerator and which can be operated from a remote position. The geometry of our scattering chamber requires that the motion (of the various targets into position) must be in the vertical direction, but that the overall height of the system be constant. These requirements are met by using an internal retractabl… more
Date: June 1, 1963
Creator: Chambers, B.; Hofstadter, R.; Marcum, A. & Yearian, M. R.
Partner: UNT Libraries Government Documents Department
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DIRECT REDUCTION OF URANIUM HEXAFLUORIDE TO URANIUM METAL WITH SODIUM

Description: Thermodynamic considerations indicate that sodium should be favorable for the one-step reduction of UF/sub 6/ to uranium metal. A reaction vessel was developed for the continuous reduction of UF/sub 6/ to metal with batch collection of the products, and several experimental tests established the chemical feasibility of this direct and continuous reduction. Up to 93.5% of the uranium content of UF/sub 6/ continuously reduced by sodium in a reaction vessel was recovered as massive uranium metal i… more
Date: April 1, 1963
Creator: Scott, C.D.
Partner: UNT Libraries Government Documents Department
open access

Lymphocyte Production Measured by Extracorporeal Irradiation, Cannulation and Labeling Techniques

Description: The labeling of newly-formed lymph cells with tritiated thymidine, lymphatic duct cannulation, and the peripheral destruction of lymphocytes by extracorporeal irradiation of the blood were used to estimate the mass of prestored lymphocytes and the relative degree of recirculation of 1ymphocytes from blood to lymph and back again. Topics discussed include the effects of extiacorporeal irradiation on the histologic picture of the lymphoreticular tissue, the influence of extracorporeal irradiation… more
Date: January 1, 1963
Creator: Cronkite, E. P.; Jansen, C. R.; Cottier, H.; Rai, K. & Sipe, C. R.
Partner: UNT Libraries Government Documents Department
open access

Atomic Binding Energies From a Modified Thomas-Fermi-Dirac Theory

Description: A quantum correction of the statistical model of the atom was obtained by modifying March and Plaskett's region of integration in the (n/sub r/,l), or quantum-number, plane. Integrations over the plane lead, in the unmodified case, to the Thomas-Fermi density expression and energy equation. Integrations over the modified region are here shown to produce a modified Thomas-Fermi expression for the electron density, and a correction to the kinetic energy. The latter correction shows a similarity t… more
Date: October 1, 1963
Creator: Barnes, J.F. & Cowan, R.D.
Partner: UNT Libraries Government Documents Department
open access

CURRENT-CARRYING CAPACITY AND TRANSITION STATE OF SUPERCONDUCTING SOLENOIDS

Description: A solenoid wound with high-field superconducting wire displays maximum currents and fields (H) that are less than the critical field of the wire itself in an equal field (H). Montgomery's and Chandraseknar and Hulm's models for these maximum properties indicate, respectively, a unique coil quenching characteristic for geometrically similar solenoids and one unique characteristic for all solenoids with identical wire type and turn distance. Experiments with Pb coils did not verify Mont… more
Date: January 1, 1963
Creator: Gauster, W F & Coffey, D L
Partner: UNT Libraries Government Documents Department
open access

ELECTRONIC DATA PROCESSING, AN APPLICATION TO NUCLEAR MATERIALS MANAGEMENT

Description: The application of an electronic data processing system to the unique combination of scientific and commercial data processing requirements of nuclear materials management is discussed. The organization and ilow of data from the plant through the data processing equipment to the final report are discussed. Included are topics concerned with the impact of conversion to electronic data processing on personnel, materials management costs, and on other plant organizations. Portions are devoted to p… more
Date: October 31, 1963
Creator: Hudson, J F
Partner: UNT Libraries Government Documents Department
open access

OXYGEN-17 NMR SHIFTS CAUSED BY Cr$sup ++$ IN AQUEOUS SOLUTIONS

Description: Cr{sup++} in solution produces a paramagnetic shift in the NMR absorption of 0{sup17} in C1O{sub4}{sup-}, as well as the expected paramagnetic shift for 0{sup17} in H{sub2}O. As the concentration of C1O{sub4}{sup-} increases, the shift in the H{sub2}O{sup17} absorption is diminished, and eventually changes sign. The effects are ascribed to preferential replacement by C1O{sub4}{sup-} of water molecules from the axial positions in the first coordination sphere about Gr{sup++}.
Date: February 15, 1963
Creator: Jackson, J.A.; Lemons, J.F. & Taube, H.
Partner: UNT Libraries Government Documents Department
open access

Radiobiological Basis for the Whole Body Radiation Syndrome

Description: Data are presented that show a marked species difference in the degree of damage and in the course of events seen in the bone marrow and peripheral blood after a given dose of radiation. The data taken together indicate strongly, but do not prove, that the picture seen results primarily from damage to the stem cell population. This damage to the stem cells is manifested later in the more mature differentiating cells of the marrow, and in the peripheral blood. The picture seen results both from … more
Date: July 19, 1963
Creator: Bond, V.P. & Fliedner, T.M.
Partner: UNT Libraries Government Documents Department
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Ecological Effects of Nuclear War

Description: No Description Available.
Date: August 1, 1963
Creator: Woodwell, G. M.
Partner: UNT Libraries Government Documents Department
open access

A NEW METHOD TO DETERMINE VARIOUS FREE ENERGY STATES OF SILVER OXIDE ON SILVER METAL

Description: The solubility of silver oxide on silver metal is not the same as that of the bulk oxide. The differences in solubility were investigated by shaking silver powder in deaerated solutions of various concentrations of ammonia and in buffers of ammonia and ammonium nitrate at a constant temperature of 25 deg C. These solutions were shaken in an atmosphere of N/sub 2/ in a stoppered bottle and in the absence of light. The concentration of silver ion in these solutions was measured potentiometrically… more
Date: October 31, 1963
Creator: van'; t Riet, B & Watt, W J
Partner: UNT Libraries Government Documents Department
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STUDIES IN CONTACT MICRO-RADIOGRAPHY

Description: A study was made of contact microradiographic techniques for the x-ray evaluation of tin specimens or selected small regions in large specimens. Extraneous absorbers such as air and the film holder were removed to permit the use of low-energy x rays, and high-resolution plates were used which permit magnifications up to 500x. Microradiographs are presented for graphite-coated uranium carbide particles, nickel screen, thin graphite section, and various fibrous materials. It is concluded that the… more
Date: October 31, 1963
Creator: McClung, R W
Partner: UNT Libraries Government Documents Department
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ENTROPY PRODUCTION AND HEAT FLOW IN LIQUID He II

Description: An analysis of the effect of mutual friction between normal fluid and superfluid in the flow of liquid He II through narrow channels under large temperature gradients was recently given by Craig, Keller, and Hammel. This analysis is based on the Gorter-Mellink thermodynamical equations. An alternative treatment of the problem is presented in which the conservation of entropy is introduced naturally into the theory at an early stage. The role played by entropy production in the processes involve… more
Date: July 1, 1963
Creator: Oliphant, T.A. Jr.
Partner: UNT Libraries Government Documents Department
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