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Fuel Management in Large Pressurized Water Reactors

Description: Economic and operational ground rules and their effects on fuel management are summarized, and examples showing the approach to typical fuel management problems are presented. The problems associated with in-core fuel management are also discussed, and the merits of various fuel cycling methods are evaluated. (D.C.W.)
Date: October 31, 1964
Creator: Dollard, W. J. & Strawbridge, L. E.
Partner: UNT Libraries Government Documents Department

Fabrication and Properties of Seamless Tungsten Tubing

Description: A process for the production of seamless tungsten tubing is described. The process consists of the extrusion of sintered powder sleeves at elevated temperatures to sizes close to the final dimension. The tubing is finished by warm drawing. A size range of 0.100-in, diameter to 1 1/2-in. diameter has been fabricated. A preliminary evaluation of properties of the extruded tubes is given. (auth)
Date: October 31, 1964
Creator: Loewenstein, P.; Hunt, J. G. & Jenkins, R. G.
Partner: UNT Libraries Government Documents Department

Simplified Analytical Model for Simulation of Boiling Water Reactors

Description: A digital computer program FLARE was developed for calculating the core reactivity and power distributions in the Big Rock Point Reactor. The calculations are restricted to a relatively coarse mesh, but good agreement was obtained in comparisons with operating data from the Kahl reactor. (D.L.C.)
Date: October 31, 1964
Creator: Fischer, D. L. & Harriman, J. M.
Partner: UNT Libraries Government Documents Department

Application of the Variational Method to the Calculation of the Time Dependence of the Neutron Flux in Small Pulsed Slabs, Cylinders and Spheres

Description: The variational method is applied to the monoenergetic time dependent transport equation to obtain a simple relation for the asymptotic decay constant in small pulsed assemblies. The results indicate that flat trial functions may be a reasonable representation of the flux distributions in the thin slab limit. This approach is superior to many of the usual transport approximations. (auth)
Date: October 31, 1964
Creator: Judge, F. D. & Daitch, P. B.
Partner: UNT Libraries Government Documents Department

$pi$$sup +$p CROSS SECTIONS BELOW 4 Gev

Description: No Description Available.
Date: January 1, 1964
Creator: James, F.E.; Johnson, J.A. & Kraybill, H.L.
Partner: UNT Libraries Government Documents Department

Operating Strategy for Maintaining an Optimum Power Distribution Throughout Life

Description: A method of operation developed for maintaining a minimum power peaking factor throughout the operating cycle of a power reactor is described. The basic operating principle for peaking factor minimization is presented, and its use in the design phase to compare and set design parameters and in the operational phase to establish control rod patterns is outlined. The method will (hopefully) increase the power density in the Big Rock Point Reactor. (D.C.W.)
Date: October 31, 1964
Creator: Haling, R. K.
Partner: UNT Libraries Government Documents Department

Nuclear spectroscopy with direct relations [Part] 2. Proceedings

Description: The Symposium on Nuclear Spectroscopy with Direct Reactions, sponsored and organized by Argonne National Laboratory under the auspices of the U. S. Atomic Energy Commission, was held on 9-11 March 1964 at the Center for Continuing Education, University of Chicago. The present volume contains the invited papers along with abstracts or summaries of the few short papers selected for their special relevance to the topics of the invited lecturers . Edited versions of the discussions are also included.
Date: March 1, 1964
Creator: Throw, F. E.
Partner: UNT Libraries Government Documents Department

OBSERVATION OF A NONSTRANGE MESON OF MASS 959 MeV

Description: No Description Available.
Date: April 4, 1964
Creator: Kalbfleisch, George R.; Alvarez, Luis W.; Barbaro-Galtieri,Angela; Dahl, Orin I.; Eberhard, Philippe; Humphrey, William E. et al.
Partner: UNT Libraries Government Documents Department

PRODUCTION OF S = 0, -1 RESONANT STATES IN K<sup>-</sup> p INTERACTIONS AT 2.45 GeV/c

Description: About 70,000 pictures of 2.45-GeV/c K{sup -}-p interactions have been obtained in the present 72-inch hydrogen bubble-chamber experiment. Approximately 24,000 events of all topologies except 1-, 2-, and 3-prong events have been measured, and 50% have been remeasured. They report here on a study of the production of known resonances in the reactions: (1) K{sup -} + p {yields} {Lambda} + {pi}{sup +} + {pi}{sup -}; (2) K{sup -} + p {yields} {Lambda} + {pi}{sup +} + {pi}{sup 0} + {pi}{sup -}. The cross section for production and number of events in reactions (1) and (2) are given in Table I.
Date: July 7, 1964
Creator: Ross, Ronald R.; Friedman, Jerome H.; Siegel, Daniel M.; Flatte,Stanley; Alvarez, Luis W.; Barbaro-Galtieri, Angela et al.
Partner: UNT Libraries Government Documents Department

CORRELATIONS BETWEEN PHOTOINDUCED EPR AND PHOTOCONDUCTIVITY INTONE-THF SOLUTION CHARGE-TRANSFER COMPLEX

Description: Reversible photoinduced electron paramagnetic resonance (EPR) signals and photoconductivity were observed when a solution of tetracyancethylene (TCNE) in tetrahydrofuran (THF) was irradiated in the charge-transfer band of the complex formed between these two compounds. The eleven-line hyperfine structure of the EPR spectrum which was obtained demonstrated the presence of TCNE negative ion radical. The concentration of this radical was found to be directly proportional to the square root of the light intensity. Second order decay kinetics were followed when the light was shut off. Both the EPR signal and the photoconductivity rose initially as the square of the time. The latter portions of the growth curves could be fit to the latter portions of a hyperbolic tangential growth curve. From these data a reaction mechanism was proposed. The rate law dn/dt + kn{sup 2} = {alpha}L(1-e{sup -{beta}t}) = 0, where n = the concentration of radicals, t = the time, k, {alpha}, and {beta} are rate constants, and L = the light intensity, described both the photo-induced EPR and the photoconductivity within the limits of experimental accuracy.
Date: December 8, 1964
Creator: Ilten, David F. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

CYANAMIDE: A POSSIBLE KEY COMPOUND IN CHEMICAL EVOLUTION

Description: The prebiotic synthesis of phosphorus-containing compounds--such as nucleotides and polynucleotides--would require both a geologically plausible source of the element and pathways for its incorporation into chemical systems on the primitive Earth. The mineral apatite, which is the only significant source of phosphate on Earth, has long been thought to be problematical in this respect due to its low solubility and reactivity. However, in the last decade or so, at least two pathways have been demonstrated which would circumvent these perceived problems. In addition, recent results would seem to suggest an additional, extraterrestrial source of reactive phosphorus. It appears that the 'phosphorus problem' is no longer the stumbling block which it was once thought to be.
Date: May 1, 1964
Creator: Steinman, Gary; Lemmon, Richard M. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

Absolute Decay Rate from K<sub>2</sub><sup>0</sup>→π<sup>+</sup> + π<sup>-</sup> + π<sup>0</sup> and the barDELTA I over→bar = 1/2 Rule

Description: In this letter the author describes a measurement of the absolute decay rate {Gamma}{sub 2}({+-}0) {approx_equal} {Gamma}(K{sub 2}{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}). The result is based on 16 events of the type {pi}{sup -} p {yields} {Lambda}K{sup 0} followed by {Lambda} {yields} p{pi}{sup -} and K{sub 2}{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}, and 2608 double-vec events {pi}{sup -} p {yields} {Lambda}K{sup 0} with {Lambda} {yields} p{pi}{sup -} and K{sub 1}{sup 0} {yields} {pi}{sup +}{pi}{sup -}.
Date: February 4, 1964
Creator: Stern, Donald; Binford, Thomas O.; Lind, V. Gordon; Anderson, Jared A.; Crawford, Jr, Frank S. & Golden, Robert L.
Partner: UNT Libraries Government Documents Department

An Automatic Lithium Drifting Apparatus for Silicon and Germanium Detectors

Description: Drifting a thick lithium-drifted counter (silicon and germanium) is a time-consuming operation that frequently results in a poor device, owing to inadequate knowledge of progress of the drifting operation. The drifting apparatus described here automatically controls the temperature of the detector that is being drifted to maintain the leakage current at a preselected value. While drifting proceeds, a continuous measurement is made of the distance of the lithium-drifted region from the opposite face of the wafer. When the drifted region reaches 30 mil or less from the back of the wafer a meter indicates the thickness of the undrifted region and, when this thickness falls below a preselected value, the temperature of the detector is automatically reduced to room temperature. The need for constant supervision of the drifting operation is thereby eliminated, and reliance on theoretical drift-rate calculations to predict the drift-through time is avoided. The technique has been applied to the manufacture of lithium-drifted silicon detectors with excellent results. The application of the technique to lithium-drifted germanium {gamma} detectors is also discussed briefly.
Date: February 8, 1964
Creator: Goulding, Fred S. & Hansen, W. L.
Partner: UNT Libraries Government Documents Department

LONGITUDINAL RESISTIVE INSTABILITIES OF INTENSE COASTING BEAMS IN PARTICLE ACCELERATORS

Description: The effect of finite resistance in the vacuum-tank walls on the longitudinal stability of an intense beam of particles in an accelerator is investigated theoretically. We show that even if the particle frequency is an increasing function of particle energy, the wall resistance can render the beam unstable against longitudinal bunching. In the absence of frequency spread in the unperturbed beam, the instability occurs with a growth rate that is proportional to (N/{sigma}){sup 1/2}, where N is the number of particles in the beam and {sigma} is the conductivity of the surface material. By means of the Vlasov equation a criterion for beam stability is obtained. In the limit of highly conducting walls the criterion involves the frequency spread in the unperturbed beam, the number of particles N, the beam energy, geometrical properties of the accelerator, but not the conductivity {sigma}. A numerical example presented indicates that certain observations of beam behavior in the MURA 40-Mev-electron accelerator may be related to the phenomenon we investigated.
Date: September 29, 1964
Creator: Neil, V. Kelvin & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department

GENERALIZATION OF THE ACTIVATED COMPLEX THEORY OF REACTION RATES. I. QUANTUM MECHANICAL TREATMENT

Description: In its usual form activated complex theory assumes a quasi-equilibrium between reactants and activated complex, a separable reaction coordinate, a Cartesian reaction coordinate, and an absence of interaction of rotation with internal motion in the complex. In the present paper a rate expression is derived without introducing the Cartesian assumption. The expression bears a formal resemblance to the usual one and reduces to it when the added assumptions of the latter are introduced. The new equation for the transmission coefficient contains internal centrifugal terms. The derivation employs an extension of the Stackel-Robertson formalism for separation of variables in mechanics. The fourth assumption can also be weakened and a rotational interaction included in the formalism. In applications of the rate equation use is made of the recent findings that in the immediate vicinity of a saddle-point or a minimum a potential energy surface can be imitated in some major topographical respects by a surface permitting separation of variables. The separated wave equation for the reaction coordinate is then curvilinear because of the usual curvature of the path of steepest ascent to the saddle-point. Calculations of transmission coefficients and rates can be made and compared with those obtainable from the usual one-dimensional Cartesian-like calculations on the one hand and with some based on the numerical integration of the n-dimensional Schrodinger equation on the other. An application to a common three-center problem is discussed.
Date: November 1, 1964
Creator: Marcus, R.A.
Partner: UNT Libraries Government Documents Department

GENERALIZATION OF THE ACTIVATED COMPLEX THEORY OF REACTION RATES. II. CLASSICAL MECHANICAL TREATMENT

Description: In its usual classical form activated complex theory assumes a particular expression for the kinetic energy of the reacting system one associated with a rectilinear motion along the reaction coordinate. The derivation of the rate expression given in the present paper is based on the general kinetic energy expression.
Date: November 1, 1964
Creator: Marcus, R.A.
Partner: UNT Libraries Government Documents Department

APPLICATIONS OF MONTE CARLO CALCULATIONS TO SGR REACTORS

Description: Monte Carlo (MC) calculations were made that show that an observed reactivity increase due to fuel rod bowing in the Sodium Reactor Experiment can be accounted for by the accompanying change in the thermal flux distribution. The questionable reliability of calculations with a simplified fuel element model that indicated the same relation prompted the MC calculations. Comparison with experimental results and results calculated by other means established the reliability of the MC calculations. (D.C.W.)
Date: October 31, 1964
Creator: Fillmore, F L
Partner: UNT Libraries Government Documents Department