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Formation of H/sup -/ by charge transfer in alkaline-earth vapors

Description: Progress since the last symposium on the study of H/sup -/ formation by charge transfer in alkaline-earth vapors is reported. High yields are obtained at low energies, in agreement with theoretical predictions.
Date: December 5, 1983
Creator: Schlachter, A.S. & Morgan, T.J.
Partner: UNT Libraries Government Documents Department
open access

Reactor Operations Management Plan

Description: The K-Reactor last operated in April 1988. At that time, K-Reactor was one of three operating reactors at the Savannah River Site (SRS). Following an incident in P-Reactor in August 1988, it was decided to discontinue SRS reactor operation and conduct an extensive program to upgrade operating practices and plant hardware prior to restart of any of the reactors. The K-reactor was the first of three reactors scheduled to resume production. At the present time, it is the only reactor with planned … more
Date: December 5, 1991
Creator: Rice, P.D.
Partner: UNT Libraries Government Documents Department
open access

Neutron-induced prompt gamma activation analysis (PGAA) of metalsand non-metals in ocean floor geothermal vent-generated samples

Description: Neutron-induced prompt gamma activation analysis (PGAA) hasbeen used to analyze ocean floor geothermal vent-generated samples thatare composed of mixed metal sulfides, silicates, and aluminosilicates.The modern application of the PGAA technique is discussed, and elementalanalytical results are given for 25 elements observed in the samples. Theelemental analysis of the samples is consistent with the expectedmineralogical compositions, and very consistent results are obtained forcomparable sample… more
Date: December 5, 2002
Creator: Perry, D. L.; Firestone, R. B.; Molnar, G. L.; Revay, Zs.; Kasztovszky, Zs.; Gatti, R. C. et al.
Partner: UNT Libraries Government Documents Department
open access

Local Two-Photon Couplings and the J=0 Fixed Pole in Real and Virtual Compton Scattering

Description: The local coupling of two photons to the fundamental quark currents of a hadron gives an energy-independent contribution to the Compton amplitude proportional to the charge squared of the struck quark, a contribution which has no analog in hadron scattering reactions. We show that this local contribution has a real phase and is universal, giving the same contribution for real or virtual Compton scattering for any photon virtuality and skewness at fixed momentum transfer squared t. The t-depende… more
Date: December 5, 2008
Creator: Brodsky, Stanley J.; Llanes-Estrada, Felipe J. & Szczepaniak, Adam P.
Partner: UNT Libraries Government Documents Department
open access

COMPARISON OF RESPONSE OF 9977 TEST PACKAGES TO ANALYTICAL RESULTS

Description: Each of the hypothetical accident test cases for the 9977 prototypes was included in the battery of finite element structural analyses performed for the package. Comparison of the experimental and analytical results provides a means of confirming that the analytical model correctly represents the physical behavior of the package. The ability of the analytical model to correctly predict the performance of the foam overpack material for the crush test is of particular interest. The dissipation of… more
Date: December 5, 2007
Creator: Smith, A & Tsu-Te Wu, T
Partner: UNT Libraries Government Documents Department
open access

14C/C measurements support Andreev's internode method to determine lichen growth rates in Cladina stygia (Fr.) Ahti

Description: Growth rates and the ability to date an organism can greatly contribute to understanding its population biology and community dynamics. 1n 1954, Andreev proposed a method to date Cladina, a fruticose lichen, using total thallus length and number of internodes. No research, however, has demonstrated the reliability of this technique or compared its estimates to those derived by other means. In this study, we demonstrate the utility of {sup 14}C/C ratios to determine lichen age and growth rate in… more
Date: December 5, 2007
Creator: Holt, E. & Bench, G.
Partner: UNT Libraries Government Documents Department
open access

Laser Tracker Calibration - Testing the Angle Measurement System -

Description: Physics experiments at the SLAC National Accelerator Laboratory (SLAC) usually require high accuracy positioning, e. g. 100 {micro}m over a distance of 150 m or 25 {micro}m in a 10 x 10 x 3 meter volume. Laser tracker measurement systems have become one of the most important tools for achieving these accuracies when mapping components. The accuracy of these measurements is related to the manufacturing tolerances of various individual components, the resolutions of measurement systems, the overa… more
Date: December 5, 2008
Creator: Gassner, Georg & Ruland, Robert
Partner: UNT Libraries Government Documents Department
open access

EVALUATION OF THERMAL CONDUCTIVITY OF INSTALLED-IN-PLACE POLYURETHANE FOAM INSULATION BY EXPERIMENT AND ANALYSIS

Description: In the thermal analysis of the 9977 package, it was found that calculated temperatures, determined using a typical thermal analysis code, did not match those measured in the experimental apparatus. The analysis indicated that the thermal resistance of the overpack in the experimental apparatus was less than that expected, based on manufacturer's reported value of thermal conductivity. To resolve this question, the thermal conductivity of the installed foam was evaluated from the experimental re… more
Date: December 5, 2007
Creator: Smith, A; Bruce Hardy, B; Kurt Eberl, K & Nick Gupta, N
Partner: UNT Libraries Government Documents Department
open access

SAFETY IMPROVES DRAMATICALLY IN FLUOR HANFORD SOIL AND GROUNDWATER REMEDIATION PROJECT

Description: This paper describes dramatic improvements in the safety record of the Soil and Groundwater Remediation Project (SGRP) at the Hanford Site in southeast Washington state over the past four years. During a period of enormous growth in project work and scope, contractor Fluor Hanford reduced injuries, accidents, and other safety-related incidents and enhanced a safety culture that earned the SGRP Star Status in the Department of Energy's (DOE's) Voluntary Protection Program (VPP) in 2007. This pap… more
Date: December 5, 2007
Creator: Gerber, M. S.
Partner: UNT Libraries Government Documents Department
open access

Decadal- to interannual-scale source water variations in the Caribbean Sea recorded by Puerto Rican coral radiocarbon

Description: Water that forms the Florida Current, and eventually the Gulf Stream, coalesces in the Caribbean from both subtropical and equatorial sources. The equatorial sources are made up of, in part, South Atlantic water moving northward and compensating for southward flow at depth related to meridional overturning circulation. Subtropical surface water contains relatively high amounts of radiocarbon ({sup 14}C), whereas equatorial waters are influenced by the upwelling of low {sup 14}C water and have r… more
Date: December 5, 2006
Creator: Kilbourne, K. H.; Quinn, T. M.; Guilderson, T. P.; Webb, R. S. & Taylor, F. W.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the CKM Angles at BaBar And Belle

Description: The primary goal of the BaBar and Belle experiments is to overconstrain the CKM Unitarity Triangle. Measurements of the angles of this triangle, known as {beta}, {alpha}, and {gamma} (or {phi}{sub 1}, {phi}{sub 2}, and {phi}{sub 3}) give insight into the Standard Model description of CP violation in the quark sector. BaBar and Belle have recorded almost 1 ab{sup -1} combined, and have measured {beta} to high precision. Measurements of {alpha} and {gamma} are less precise at present, but both ex… more
Date: December 5, 2007
Creator: Barlow, Nick
Partner: UNT Libraries Government Documents Department
open access

Universal Entanglement Entropy in 2D Conformal Quantum Critical Points

Description: We study the scaling behavior of the entanglement entropy of two dimensional conformal quantum critical systems, i.e. systems with scale invariant wave functions. They include two-dimensional generalized quantum dimer models on bipartite lattices and quantum loop models, as well as the quantum Lifshitz model and related gauge theories. We show that, under quite general conditions, the entanglement entropy of a large and simply connected sub-system of an infinite system with a smooth boundary ha… more
Date: December 5, 2008
Creator: Hsu, Benjamin; Mulligan, Michael; Fradkin, Eduardo & Kim, Eun-Ah
Partner: UNT Libraries Government Documents Department
open access

Total cross sections and elastic scattering at the SSC

Description: The need is discussed of a special purpose detector for the measurement of elastic scattering at the SSC. The detector would cover as small a solid angle as is practical. Two techniques are described briefly to measure total cross sections at hadron storage rings. The direct method is to measure the interaction rate in an IR of known luminosity - a method that gets more difficult increasing energy. A second method is to use the optical theorem. 6 refs., 1 fig. (LEW)
Date: December 5, 1985
Creator: Foley, K.J.
Partner: UNT Libraries Government Documents Department
open access

Some limitations of detailed balance for inverse reaction calculations in the astrophysical p-process

Description: p-Process modeling of some rare but stable proton-rich nuclei requires knowledge of a variety of neutron, charged particle, and photonuclear reaction rates at temperatures of 2 to 3 {times} 10{sup 9} {degrees}K. Detailed balance is usually invoked to obtain the stellar photonuclear rates, in spite of a number of well-known constraints. In this work we attempt to calculate directly the stellar rates for ({gamma},n) and ({gamma},{alpha}) reactions on {sup 151}Eu. These are compared with stellar r… more
Date: December 5, 1990
Creator: Gardner, D. G. & Gardner, M. A.
Partner: UNT Libraries Government Documents Department
open access

Star-disk collisions in active galactic nuclei and the origin of the broad line region

Description: Stars of a cluster surrounding the central black hole in an AGN will collide with the accretion disk. For a central black hole of 10{sup 8} M{circle dot} and a cluster with 10{sup 7} {minus} 10{sup 8} stars within a parsec, one estimates that {approximately}10{sup 4} such collisions will occur per year. Collisions are hypersonic (Mach number M {much gt} 1). Some of the wake of the star -- the disk material shocked by its passage -- will follow it out of the disk. Such star tails'' with the esti… more
Date: December 5, 1991
Creator: Zurek, W.H.; Colgate, S.A. (Los Alamos National Lab., NM (United States)) & Siemiginowska, A. (Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States))
Partner: UNT Libraries Government Documents Department
open access

US nuclear weapons policy

Description: We are closing chapter one'' of the nuclear age. Whatever happens to the Soviet Union and to Europe, some of the major determinants of nuclear policy will not be what they have been for the last forty-five years. Part of the task for US nuclear weapons policy is to adapt its nuclear forces and the oganizations managing them to the present, highly uncertain, but not urgently competitive situation between the US and the Soviet Union. Containment is no longer the appropriate watchword. Stabilizati… more
Date: December 5, 1990
Creator: May, M.
Partner: UNT Libraries Government Documents Department
open access

Fusion target design

Description: Most detailed fusion target design is done by numerical simulation using large computers. Although numerical simulation is briefly discussed, this lecture deals primarily with the way in which basic physical arguments, driver technology considerations and economical power production requirements are used to guide and augment the simulations. Physics topics discussed include target energetics, preheat, stability and symmetry. A specific design example is discussed.
Date: December 5, 1978
Creator: Bangerter, R.O.
Partner: UNT Libraries Government Documents Department
open access

Corrosion of steel tendons used in prestressed concrete pressure vessels

Description: The purpose of this investigation was to determine the corrosion behavior of a high strength steel (ASTM A416-74 grade 270), typical of those used as tensioning tendons in prestressed concrete pressure vessels, in several corrosive environments and to demonstrate the protection afforded by coating the steel with either of two commercial petroleum-base greases or Portland Cement grout. In addition, the few reported incidents of prestressing steel failures in concrete pressure vessels used for co… more
Date: December 5, 1978
Creator: Griess, J. C. & Naus, D. J.
Partner: UNT Libraries Government Documents Department
open access

Impaired fertility in T-stock female mice after superovulation

Description: Superovulation of female mice with exogenous gonadotrophins is routinely used for increasing the number of eggs ovulated by each female in reproductive and developmental studies. We report an unusual effect of superovulation on fertilization in mice. In vivo matings of superovulated T-stock females with B6C3F1 males resulted in a 2-fold reduction (P<0.001) in the frequencies of fertilized eggs compared to control B6C3F1 matings. In addition, {approx}22 hr after mating only 15% of fertilized … more
Date: December 5, 2003
Creator: Wyrobek, A J; Bishop, J B; Marchetti, F & Zudova, D
Partner: UNT Libraries Government Documents Department
open access

Hyperspectral Imaging of Functional Patterns for Disease Assessment and Treatment Monitoring

Description: We have designed and built a six-band multi-spectral NIR imaging system used in clinical testing on cancer patients. From our layered tissue model, we create blood volume and blood oxygenation images for patient treatment monitoring.
Date: December 5, 2003
Creator: Hassan, Moinuddin; Hattery, David; Vogel, Abby; Chernomorkik, Victor; Demos, Stavros; Aleman, Karen et al.
Partner: UNT Libraries Government Documents Department
open access

Sampling a two-phase geothermal brine flow for chemical analysis

Description: An experiment designed primarily to define the problems associated with sampling the two-phase flow in a pipeline of geothermal brine is described. Analyses reported for 26 samples include chemical composition, oxidation potential, pH, density, and total solids. Changes in brine composition as the well operated during a four-week period are evaluated. The apparatus and techniques used for sampling are described and evaluated. (auth)
Date: December 5, 1975
Creator: Hill, J. H. & Morris, C. J.
Partner: UNT Libraries Government Documents Department
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