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A Preliminary measurement of the gluon splitting rate into b\bar{b} pairs in hadronic Z0 decays

Description: We present a measurement of the rate of gluon splitting into bottom quarks, g --> b anti-b, in hadronic Z<sup>0</sup> decays collected by SLD from 1996 to 1998. The analysis was performed by looking for secondary bottom production in 4-jet events of any primary avor. A topological vertex mass technique was used to tag the two jets with the smallest angle between them as b/anti-b. We obtained a rate of g --> b anti-b per hadronic event to be (3.07 ± 0.71(stat:) ± 0.66(syst:)) × 10&sup3; (prelimi… more
Date: June 10, 1999
Creator: Abe, Toshinori
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of Ignition Testing on K-West Basin Fuel

Description: Approximately 2100 metric tons of spent nuclear fuel (SNF) discharged from the N-Reactor have been stored underwater at the K-Basins in the 100 Area of the Hanford Site. The spent fuel has been stored in the K-East Basin since 1975 and in the K-West Basin since 1981. Some of the SNF elements in these basins have corroded because of various breaches in the Zircaloy cladding that occurred during fuel discharge operations and/or subsequent handling and storage in the basins. Consequently, radioact… more
Date: August 10, 1999
Creator: Abrefah, J.; Huang, F.H.; Gerry, W.M.; Gray, W.J.; Marschman, S.C. & Thornton, T.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of Ignition Testing on K-West Basin Fuel

Description: Ignition tests and analyses of damage/corroded N-Reactor spent nuclear fuel (SNF) were performed by Pacific Northwest National Laboratory as part of a series of studies on the deteriorating spent fuel in the Hanford K-Basins. The ignition temperature tests were conducted to assess tie pyrophoric properties of selected spent fuel elements from K-West Basin. The objective of these tests was to determine pyrophoric characteristics of samples cut from both damaged and undamaged regions of fhel elem… more
Date: August 10, 1999
Creator: Abrefah, John; Huang, Fan-Hsiung F.; Gerry, William M.; Gray, Walter J.; Marschman, Steven C. & Thornton, Thomas A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Theory of high-{Tc} superconducting cuprates based on experimental evidence

Description: A model of superconductivity in layered high-temperature superconducting cuprates is proposed, based on the extended saddle point singularities in the electron spectrum, weak screening of the Coulomb interaction and phonon-mediated interaction between electrons plus a small short-range repulsion of Hund's, or spin-fluctuation, origin. This permits to explain the large values of {Tc}, features of the isotope effect on oxygen and copper, the existence of two types of the order parameter, the peak… more
Date: December 10, 1999
Creator: Abrikosov, A. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The status of APS, BESSRC, and NEET.

Description: We present a brief summary of the current status of the Advanced Photon Source (APS) at Argonne National Laboratory and of the facilities at two of the APS sectors operated by the Basic Energy Sciences Synchrotrons Radiation Center (BESSRC). This is followed by a report on recent measurements at BESSRC on the phenomenon of Nuclear Excitation by Electronic Transition (NEET).
Date: March 10, 1999
Creator: Ahmad, I.; Dunford, R. W.; Esbensen, H.; Gemmell, D. S.; Kanter, E. P.; Kraessig, B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An x-ray fluorescence study of lake sediments from ancient Turkey using synchrotron radiation.

Description: Sediments from relic Lake Golbasi were analyzed by X-ray fluorescence with synchrotrons radiation to determine changes in element concentrations over time with selected elements serving as proxies for environmental change. Increases in Ca and Sr suggest soil formation during a dry period, from ca. 4500 BC to ca. 200 AD at which point K, Rb, Zr, Ti, and Y increase, indicating the return of a wet environment. Soil erosion, represented by Cr and Ni, increases ca. 7000 BC, probably as a consequence… more
Date: March 10, 1999
Creator: Alatas, A.; Alp, E. E.; Friedman, E. S.; Jennings, G.; Johnson, C. E.; Lai, B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Behavior of nanocrystalline Xe precipitates in Al under 1 MeV electron irradiation.

Description: Crystalline nanoprecipitates of Xe have been produced by ion implantation into high purity Al at 300 K. With an off-zone axis TEM imaging technique, the nanocrystals may be clearly structure imaged against a nearly featureless background. Under the 1 MeV electron irradiation employed for the HREM observation, Xe nanocrystals exhibit a number of readily observed physical phenomena including migration within the matrix, changes in shape, faulting, melting, crystallization and coalescence. The var… more
Date: March 10, 1999
Creator: Allen, C. W.; Birtcher, R. C.; Donnelly, S. E.; Furuya, K.; Mitsuishi, K. & Song, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Observation of an elementary cuboctahedron of Xe nanocrystal in an Al matrix.

Description: When a noble gas element such as Xe is implanted in an fcc metal matrix such as Al at room temperature, a fine dispersion of precipitates forms. The precipitates are elementary fcc crystals up to diameters of several nanometers (for Xe in Al, 8-10 rim), above which they are non-crystalline. The precipitates exhibit a cube-on-cube orientation relation with the matrices and have lattice parameters which are much larger than those of the matrices (a{sub Xe} = 1.5a{sub Al}). Thus the interphase int… more
Date: March 10, 1999
Creator: Allen, C. W.; Birtcher, R. C.; Donnelly, S. E.; Furuya, K.; Ryan, E. A. & Song, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Neural Network-Based Resistance Spot Welding Control and Quality Prediction

Description: This paper describes the development and evaluation of neural network-based systems for industrial resistance spot welding process control and weld quality assessment. The developed systems utilize recurrent neural networks for process control and both recurrent networks and static networks for quality prediction. The first section describes a system capable of both welding process control and real-time weld quality assessment, The second describes the development and evaluation of a static neu… more
Date: July 10, 1999
Creator: Allen, J.D., Jr.; Ivezic, N.D. & Zacharia, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neural Network method for Inverse Modeling of Material Deformation

Description: A method is described for inverse modeling of material deformation in applications of importance to the sheet metal forming industry. The method was developed in order to assess the feasibility of utilizing empirical data in the early stages of the design process as an alternative to conventional prototyping methods. Because properly prepared and employed artificial neural networks (ANN) were known to be capable of codifying and generalizing large bodies of empirical data, they were the natural… more
Date: July 10, 1999
Creator: Allen, J.D., Jr.; Ivezic, N.D. & Zacharia, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Cross-Sectional Scanning Tunneling Microscopy of InAsSb/InAsP Superlattices

Description: Cross-sectional scanning tunneling microscopy has been used to characterize compositional structure in InAs{sub 0.87}Sb{sub 0.13}/InAs{sub 0.73}P{sub 0.27} and InAs{sub 0.83}Sb{sub 0.17}/InAs{sub 0.60}P{sub 0.40} strained-layer superlattice structures grown by metal-organic chemical vapor deposition. High-resolution STM images of the (110) cross section reveal compositional features within both the InAs{sub x}Sb{sub 1{minus}x} and InAs{sub y}P{sub 1{minus}y} alloy layers oriented along the [{ba… more
Date: February 10, 1999
Creator: Allerman, A. A.; Biefeld, R. M.; Yu, E. T. & Zuo, S. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Developing a CD-CBM Anticipatory Approach for Cavitation - Defining a Model Descriptor Consistent Between Processes

Description: A major problem with cavitation in pumps and other hydraulic devices is that there is no effective method for detecting or predicting its inception. The traditional approach is to declare the pump in cavitation when the total head pressure drops by some arbitrary value (typically 3o/0) in response to a reduction in pump inlet pressure. However, the pump is already cavitating at this point. A method is needed in which cavitation events are captured as they occur and characterized by their proces… more
Date: May 10, 1999
Creator: Allgood, G. O.; Dress, W. B. & Kercel, S. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development and evaluation of high resolution quadrupole mass analyzer and an inductively coupled plasma-Mach disk

Description: By definition a plasma is an electrically conducting gaseous mixture containing a significant concentration of cations and electrons. The Inductively Coupled Plasma (ICP) is an electrodeless discharge in a gas at atmospheric pressure. This discharge is an excellent one for vaporizing, atomizing, and ionizing elements. The early development of the ICP began in 1942 by Babat and then by Reed in the early 1960s. This was then followed by the pioneering work of Fassel and coworkers in the late 1960… more
Date: December 10, 1999
Creator: Amad, Ma'an Hazem
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Glass Waste Forms for Oak Ridge Tank Wastes: Fiscal Year 1998 Report for Task Plan SR-16WT-31, Task B

Description: Using ORNL information on the characterization of the tank waste sludges, SRTC performed extensive bench-scale vitrification studies using simulants. Several glass systems were tested to ensure the optimum glass composition (based on the glass liquidus temperature, viscosity and durability) is determined. This optimum composition will balance waste loading, melt temperature, waste form performance and disposal requirements. By optimizing the glass composition, a cost savings can be realized dur… more
Date: May 10, 1999
Creator: Andrews, M.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Remote sensing of the atmosphere for environmental assessment and national security

Description: The research performed this year marked the beginning of a collaboration between Howard University and LLNL to advance and apply remote sensing technology to a broad range of applications centered on probing the state of the atmosphere. Central to this research was the evolution of a telescope facility at Howard University into an atmospheric observatory and instrument development test-bed. Our work in applying laser technology to remote sensing helped lead to the development and subsequent pat… more
Date: June 10, 1999
Creator: Arens, J. F.; Davis, E.; Farah, A.; Molitoris, J. D. & Venable, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The STAR Time Project Chamber

Description: Paper presented at the International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (1999) reporting on the progress of the STAR experiment, a complex system of many detector sub-systems which have been installed in a large solenoidal magnet at the Relativistic Heavy Ion Collider (RHIC).
Date: May 10, 1999
Creator: Argonne National Laboratory
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Isentropic Compression of Iron with the Z Accelerator

Description: Development of isentropic loading techniques is a long standing goal of the shock physics community. The authors have used the Sandia Z Accelerator to produce smoothly increasing pressure loading on planar iron specimens over time durations of 100 ns and for pressures to 300 Mbar. Free surface velocity measurements on the rear surface of the continuously loaded specimens were made on specimens 0.5-mm and 0.8-mm thick and clearly show the effects of wave evolution into the well known two-wave st… more
Date: June 10, 1999
Creator: Asay, J. R.; Bernard, M. A.; Hall, C. A.; Hayes, D. B.; Holland, K. G.; McDaniel, D. H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High-dielectric-constant ferroelectric thin film and bulk ceramic capacitors for power electronics.

Description: Significant effort is presently focused on reducing the size and weight of power electronic modules. To achieve these goals in high-power capacitors, alternative materials and fabrication processes are needed. Thin film (&lt;0.5 {micro}m) and bulk capacitors that use perovskite-based ferroelectric dielectrics are promising alternative technologies. Ferroelectrics possess high dielectric constants, thus offering substantial increases in volumetric capacitance. In thin film form, these materials … more
Date: August 10, 1999
Creator: Auciello, O. H.; Baldo, P.; Baumann, P.; Erck, R. A.; Giumarra, J.; Im, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

In situ mass spectroscopy of recoiled ion studies of degradation processes in SrBi{sub 2}Ta{sub 2}O{sub 9} thin films during hydrogen gas annealing.

Description: It is known that the forming gas (N{sub 2}-H{sub 2} mixture) annealing process required for microcircuit fabrication results in an unacceptable electrical degradation of SrBi{sub 2}Ta{sub 2}O{sub 9} (SBT) ferroelectric capacitors due mainly to the interaction of H{sub 2} with the ferroelectronic layer of the capacitor. We have found a strong relationship between changes in the surface composition of the ferroelectric layer and the electrical properties of SBT capacitors as a result of hydrogen … more
Date: March 10, 1999
Creator: Auciello, O.; Chang, R. P. H.; Gruen, D. M.; Im, J.; Kim, S. H.; Kingon, A. I. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Finance and supply management project execution plan

Description: As a subproject of the HANDI 2000 project, the Finance and Supply Management system is intended to serve FDH and Project Hanford major subcontractor with financial processes including general ledger, project costing, budgeting, and accounts payable, and supply management process including purchasing, inventory and contracts management. Currently these functions are performed with numerous legacy information systems and suboptimized processes.
Date: February 10, 1999
Creator: BENNION, S.I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Software configuration management plan for HANDI 2000 business management system

Description: The Software Configuration Management Plan (SCMP) describes the configuration management and control environment for HANDI 2000 for the PP and PS software, as well as any custom developed software. This plan establishes requirements and processes for uniform documentation and coordination of HANDI 2000. This SCMP becomes effective as of this document's acceptance and will provide guidance through implementation efforts.
Date: February 10, 1999
Creator: BENNION, S.I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Production of {phi} mesons in Au-Au collisions at the AGS.

Description: The first measurements of {phi} meson production in Au-Au collisions at AGS energies are presented via the decay to K{sup +} K{sup {minus}}. A measurement of the centrality dependence of the yield shows an increase similar to that seen for the K{sup {minus}} with a spectral shape consistent with a relativistic Breit-Wigner distribution within the statistical errors of the present data set. Future analysis using the full data set with 4 times the statistics will allow a more accurate determinati… more
Date: August 10, 1999
Creator: Back, B. B.; Betts, R. R.; Chang, J.; Collaboration, E917; Gillitzer, A.; Henning, W. F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Coherent Electromagnetic Heavy Ion Reactions: (1) Exact Treatment of Pair Production and Ionization; (2) Mutual Coulomb Dissociation

Description: Some recent theoretical results on coherent electromagnetic processes in ultrarelativistic heavy ion reactions are surveyed. In ultrarelativistic heavy ion collisions, Coulomb induced cross sections are huge, much larger than geometric. For the RHIC case of 100 GeV x 100 GeV colliding gold ions the predicted cross section for bound-electron positron pairs is about 110 barns. The corresponding cross section for continuum electron-positron pairs has recently been recalculated to be 34,000 barns, … more
Date: May 10, 1999
Creator: Baltz, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Weak interaction studies with an on-line Penning trap mass spectrometer.

Description: Superallowed {beta}-decays are a sensitive probe of the fundamental aspects of the weak interaction. Such decays are used to stringently test the CVC hypothesis, deduce a precise value of the weak vector coupling constant, test the unitarity of the CKM matrix and look for deviation from the V-A structure for the weak interaction. The ability to efficiently capture and store short-lived superallowed beta-emitters in ion traps will help to elucidate discrepancies in the most precise unitarity tes… more
Date: March 10, 1999
Creator: Barber, R. C.; Buchinger, F.; Crawford, J. E.; Feng, X.; Gulick, S.; Hackman, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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