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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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Evaluation of Resonance Capture Approximations

Description: The program KRUDE, which solves the slowing down and adjoint equations for a mixture of resonance and nonresonance isotopes in an infinite homogeneous medium, was used to evaluate some resonance capture approximations (variational and successive) that use linear combinations of narrow and wide resonance fluxes. Results obtained for resonance capture in the 291-ev resonance of Zr/sup 91/ and the 192-ev resonance of U/sup 238/ are compared, and three methods for including Doppler effects in the v… more
Date: November 21, 1963
Creator: Edgar, K. R.
Partner: UNT Libraries Government Documents Department
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The Factors Limiting the Utilization of Zirconium Alloys in Superheated Steam

Description: New experimental data and literature data are utilized to determine the upper temperature of usefulness of zirconium alloys. Three basic engineering assumptions are used: (1) service life requirements are on the order of four years; (2) tubular fuel cladding for rod-type fuel is considered with a maximum wall thickness of 1.27 cm; and (3) heat fluxes are above 157 watts/cm/sup 2/. The interrelation of three basic factors, corrosion rate, corrosion embrittiement by hydrogen and oxygen, and stren… more
Date: November 20, 1963
Creator: Klepfer, H H & Douglass, D L
Partner: UNT Libraries Government Documents Department
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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
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BETA RADIATION PROCESSING AT RIGOROUS CONDITIONS

Description: An investigation was conducted on the impossible use of beta radiation to promote chemical reactions at high temperatures and pressures. The advantages of beta sources over other radiation sources are enumerated. A radiation processing apparatus is described which allows operations to 10,000 psi and 500 deg C and uses 90 C of Sr/sup 90/-Y/sup 90/. The dosimetry of the source was accomplished with an iodineheptane system, and the mean dose rate within the chemical reactor was determined to be 0.… more
Date: November 15, 1963
Creator: Yavorsky, P M & Gorin, E
Partner: UNT Libraries Government Documents Department
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Atom to Adam

Description: This report talks about the molecules which constitute today's living organisms
Date: November 1, 1963
Creator: Calvin, Melvin & Calvin, G. J.
Partner: UNT Libraries Government Documents Department
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Buckling Measurements-Heavy Natural Uranium Tubular Fuel Assemblies

Description: One-region buckling measurements that were made on a series of D/sub 2/O- moderated lattices of heavy uranium metal tubes in the Process Development Pile at Savannah River Laboratory are presented. The purposes of these measurements are to provide normalization points for lattice bucklings and to extend the study of natural uranium- D/sub 2/O systems. The dependence of buckiing on the moderatorto-fuel ratio is studied for two types of lattices. (R.E.U.)
Date: November 1, 1963
Creator: Dunklee, A. E. & Graves, W. E.
Partner: UNT Libraries Government Documents Department
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MEAN SQUARE VOLTAGE FLUCTUATION MEASUREMENTS WITH NEUTRON-SENSITIVE ION CHAMBERS

Description: The mean square fluctuation voltage in neutron sensitiv ion chambers was measured rather than the d-c current to improve gamma discrimination and eliminate d-c cable leakage interference currents. The circuitry and chambe are described, and performance in the mean square volta mode is compared with that in the d-c current mode. (D.C.W.)
Date: November 1, 1963
Creator: DuBridge, R A
Partner: UNT Libraries Government Documents Department
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Mechanical Properties of Thin Films. Technical Report No. 29

Description: vention of the Society for Nondestructive Testing. The elastic and plastic properties are reviewed with special emphasis on metal films prepared by vacuum evaporation, although work with both non-metals and other preparation techniques is discussed when it is the only existing data or has particular importance. A definite lack of agreement exists among the various workers and as a result detailed explanations are not possible although general suggestions do exist. The structure of thick polycry… more
Date: November 1, 1963
Creator: Hoffman, R W
Partner: UNT Libraries Government Documents Department
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Reactivity Worth of Transverse Gaps

Description: Fuel blocks of compacted ZrO/sub 2/ and UO/sub 2/ powder in paraffin were added axially to two unreflected assemblies (20 x 16 in. and 20 x 24 in. cross sections). The separation of the assembly halves when criticality occurred was determined, and the reactivity worth at a given critical gap size was obtained by bringing the halves slightly closer together and observing the reactor period. The core with the larger cross section had a maximum gap twice that of the smaller core. Diffusion theory … more
Date: November 1, 1963
Creator: Weinstein, S. & Feiner, F.
Partner: UNT Libraries Government Documents Department
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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
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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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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
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

Coherent Nuclear Scattering Amplitudes and Cross Sections as Determined by Neutron Diffraction Techniques

Description: The diffraction techniques used at ANL to obtain scattering amplitudes and cross sections for elements and isotopes are briefly described; and some results obtained for Zr, Tc/sup 89/, Os, Os/sup 188/, Os/sup 189/, Os/sup 190/, Os/sup 192/, K, K /sup 39/, Rb, Rb/sup 85/, Ir, and Mg are summarized. (D.C.W.)
Date: October 1, 1963
Creator: Mueller, M. H.; Sidhu, S. S.; Heaton, L.; Hitterman, R. L. & Knott, H. W.
Partner: UNT Libraries Government Documents Department
open access

FAST ANALOGUE MULTIPLIERS WITH FIELD-EFFECT TRANSISTORS

Description: The solution time of analog multipliers using field-effect transistors is investigated. This time is ultimately limited by the charging time of the transistor junction. In typical devices suitable for analog multiplication, the charging time is found to be about 10 to 20 nsec for a multiplication error of < 1%. A four quadrant pulse amplitude multiplier circuit with a solution time equal to the transistor charging time is described. (auth)
Date: October 1, 1963
Creator: Radeka, V.
Partner: UNT Libraries Government Documents Department
open access

Gamma Amplifier-Discriminator

Description: For applications involving the routine laboratory measurement of gamma radiation, an instrument is described which is simple to opeiate, versatile, compact, and reliable. It consists of a pulse amplifier with charge-sensitive input and delay-line shaping, a differential discriminator capable of covering the range from 2 kev to 7 Mev, a calibration pulser, and a power supply. All controls are calibrated directly in terms of gamma energy. Construction is modular for ease of maintenance, and all c… more
Date: October 1, 1963
Creator: Sewell, Curtis, Jr.
Partner: UNT Libraries Government Documents Department
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