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Calorimetric study of the transitions between the different vortex states in YBa{sub 2}Cu{sub 3}O{sub 7}.

Description: We have studied the vortex phase diagram of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (YBCO) in very strong magnetic field (0-26 Tesla) by a.c. calorimetry. We describe the anomalies associated with the transitions between the different vortex states (solid, liquid, and glass), with special emphasis on the first order flux lattice melting.
Date: August 17, 1999
Creator: Bouquet, F.; Calemczuk, R.; Crabtree, G. W.; Erb, A.; Fisher, R. A.; Junod, A. et al.
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Partner: UNT Libraries Government Documents Department
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CP Violation and B Physics

Description: This is a quick review of CP non-conservation in B physics. Several methods are described for testing the Kobayashi-Maskawa single phase origin of CP violation in B decays, pointing out some limitations due to hadronic uncertainties. A few characteristic signatures of new physics in B decay asymmetries are listed.
Date: August 17, 1999
Creator: Gronau, Michael
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Decay heat removal by natural convection - the RVACS system.

Description: In conclusion, this work shows that for sodium coolant the reactor vessel auxiliary cooling system (RVACS) is an effective passive heat removal system if the reactor power does not exceed about 1600 MW(th). Its effectiveness is limited by the effective radiative heat transfer coefficient in the inner gap. In a lead cooled system, economic considerations may impose a lower limit.
Date: August 17, 1999
Creator: Tzanos, C. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Deformations and stress in PMMA during hard x-ray exposure for deep lithography.

Description: The availability of high-energy, high-flux, collimated synchrotrons radiation has extended the application of deep X-ray lithography (DXRL) to thickness values of the PMMA resist of several millimeters. Some of the most severe limitations come from plastic deformation, stress, and cracks induced in PMMA during exposure and development. We have observed and characterized these phenomena quantitatively. Profilometry measurements revealed that the PMMA is subjected either to local shrinkage or to … more
Date: August 17, 1999
Creator: Moldovan, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DIRC Dreams: Research Directions for the Next Generation of Internally Reflected Imaging Counters

Description: Some conceptual design features of the total internally reflecting,imaging Cherenkov counter (DIRC) are described. Limits of the DIRC approach to particle identification, and a few features of alternative DIRC designs, are briefly explored.
Date: August 17, 1999
Creator: Ratcliff, Blair N
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ENRAF Series 854 Advanced Technology Gauge (ATG) Acceptance Test Procedure

Description: This procedure provides acceptance testing for Enraf Series 854 level gauges used to monitor levels in Hanford Waste Storage Tanks. The test will verify that the gauge functions according to the manufacturer's instructions and specifications and is properly setup prior to being delivered to the tank farm area. This ATP does not set up the gauge for any specific tank, but is generalized to permit testing the gauge prior to installation package preparation.
Date: August 17, 1999
Creator: HUBER, J.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Financing Solar Energy Systems with Energy Savings Performance Contracts in the Federal Sector: Results of a Survey on Barriers

Description: This report summarizes the findings of an investigation into financing solar energy systems for the Federal sector. The objectives of the investigation were (1) to identify the barriers that impede companies from using Energy Savings Performance Contracts (ESPCs) to develop solar energy projects for Federal facilities, and (2) to clarify the impacts of Federal contracting requirements on energy service companies' use of ESPCs. Twenty-four representatives of energy service companies agreed to be… more
Date: August 17, 1999
Creator: Gee, R. C. & LaPorta, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Groundwater Monitoring Plan for the Nonradioactive Dangerous Waste Landfill

Description: The Nonradioactive Dangerous Waste Landfill (NRDWL), which received nonradioactive hazardous waste between 1975 and 1985, is located in the central Hanford Site (Figure 1.1) in southeastern Washington State. The Solid Waste Landfill, which is regulated and monitored separately, is adjacent to the NRDWL. The NRDWL is regulated under the Resource Conservation and Recovery Act of 1976 (RCRA) and monitored by Pacific Northwest National Laboratory. Monitoring is done under interim-status, indicator-… more
Date: August 17, 1999
Creator: Lindberg, J.S. & Hartman, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Porosity in Polysilsesquioxane Xerolgels

Description: Polymerization of organotrialkoxysilanes is a convenient method for introducing organic functionality into hybrid organic-inorganic materials. However, not much is known about the effects of the organic substituent on the porosity of the resulting xerogels. In this study, we prepared a series of polysilsesquioxane xerogels from organotrialkoxysilanes, RSi(OR{sup 1}){sub 3}, with different organic groups (R = H, Me, Et dodecyl, hexadecyl, octadecyl, vinyl, chloromethyl, (p-chloromethyl) phenyl, … more
Date: August 17, 1999
Creator: Baugher, B.M.; Loy, D.A. & Rahimian, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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RESERVOIR CHARACTERIZATION OF THE LOWER GREEN RIVER FORMATION, SOUTHWEST UINTA BASIN, UTAH

Description: The +2000-foot-thick (600-m), Tertiary-aged lacustrine deposits of the Middle and Lower Members of the Green River Formation contain the primary oil-producing reservoirs in the southwest Uinta Basin. The authors developed a log-based correlation scheme by identifying what they interpret as depositional cycles on the gamma-ray and resistivity logs of several wells. Regional cross sections were constructed and cycle boundaries revised as needed. The cycles typically range from 50 to 100 feet (15-… more
Date: August 17, 1999
Creator: Morgan, C.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rural Utilities Service: Status of Electric Loan Portfolio

Description: Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the Rural Utilities Service's (RUS) generation and transmission (G&T) borrowers and assessed the likelihood of the federal government incurring losses in the future on loans to G&T borrowers."
Date: August 17, 1999
Creator: United States. General Accounting Office.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
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Seismic studies of the San Francisco-Oakland Bay Bridge

Description: Computational simulation plays a central role in the engineering analysis and design of major bridge structures and accurate simulations are essential for the development of earthquake resistant and economical structural designs. This paper describes new methodologies and computational tools which have recently been developed for simulating earthquake ground motions and the seismic response of cable supported bridges. The simulation tools are described and an example application for an importan… more
Date: August 17, 1999
Creator: Astaneh-Asl, A.; Larsen, S. & McCallen, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The smoke-fireplume model : tool for eventual application to prescribed burns and wildland fires.

Description: Land managers are increasingly implementing strategies that employ the use of fire in prescribed burns to sustain ecosystems and plan to sustain the rate of increase in its use over the next five years. In planning and executing expanded use of fire in wildland treatment it is important to estimate the human health and safety consequences, property damage, and the extent of visibility degradation from the resulting conflagration-pyrolysis gases, soot and smoke generated during flaming, smolderi… more
Date: August 17, 1999
Creator: Brown, D. F.; Dunn, W. E.; Lazaro, M. A. & Policastro, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Software for the parallel adaptive solution of conservation laws by discontinous Galerkin methods.

Description: The authors develop software tools for the solution of conservation laws using parallel adaptive discontinuous Galerkin methods. In particular, the Rensselaer Partition Model (RPM) provides parallel mesh structures within an adaptive framework to solve the Euler equations of compressible flow by a discontinuous Galerkin method (LOCO). Results are presented for a Rayleigh-Taylor flow instability for computations performed on 128 processors of an IBM SP computer. In addition to managing the distr… more
Date: August 17, 1999
Creator: Flaherty, J. E.; Loy, R. M.; Shephard, M. S. & Teresco, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Space Station: Russian Commitment and Cost Control Problems

Description: A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the status of Russian involvement in the International Space Station (ISS) program, focusing on: (1) the National Aeronautics and Space Administration's (NASA) progress in developing contingency plans to mitigate the possibility of Russian nonperformance and the loss or delay of other critical components; (2) NASA's efforts to ensure that Russian quality assura… more
Date: August 17, 1999
Creator: United States. General Accounting Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of spheromaks compressed by liquid walls

Description: We consider Rayleigh-Taylor instability of the liquid-plasma interface of a spheromak ignited by slow compression discussed previously. We conclude that instability may indeed occur despite the stabilizing influence of magnetic shear in the spheromak. If it occurs, instability would be greatest for modes concentrated toward the midplane. As for the cylindrical LINUS configuration, rotation about the geometric axis would stabilize these modes, but at the price of roughly doubling the input energ… more
Date: August 17, 1999
Creator: Fowler, T K
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of spheromaks compressed by liquid walls

Description: We consider Rayleigh-Taylor instability of the liquid-plasma interface of a spheromak ignited by slow compression discussed previously. We conclude that instability may indeed occur despite the stabilizing influence of magnetic shear in the spheromak. If it occurs, instability would be greatest for modes concentrated toward the midplane. As for the cylindrical LINUS configuration, rotation about the geometric axis would stabilize these modes, but at the price of roughly doubling the input energ… more
Date: August 17, 1999
Creator: Fowler, T K
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Terascale spectral element algorithms and implementations.

Description: We describe the development and implementation of an efficient spectral element code for multimillion gridpoint simulations of incompressible flows in general two- and three-dimensional domains. We review basic and recently developed algorithmic underpinnings that have resulted in good parallel and vector performance on a broad range of architectures, including the terascale computing systems now coming online at the DOE labs. Sustained performance of 219 GFLOPS has been recently achieved on 20… more
Date: August 17, 1999
Creator: Fischer, P. F. & Tufo, H. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theory of high-T{sub c} 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 T{sub c}, features of the isotope effect on oxygen and copper, the existence of two types of the order parameter, the … more
Date: August 17, 1999
Creator: Abrikosov, A. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Three-dimensional modeling of a time-of-flight mass spectrometer : optimization of SNMS/SIMS transmission using Simion.

Description: A computer program that models secondary ion and post-ionized neutral trajectories through the SARISA instrument has been developed. The program has been tested by determining the transmission of secondary ions for two different ion energies. Results indicate that the model accurately reflects the transmission of the SARISA instrument. The developed algorithm for creating ions and monitoring their parameters is generic and can be used for examining other SIMS/SNMS instruments and ion sources.
Date: August 17, 1999
Creator: Calaway, W. F.; Pellin, M. J. & Veryovkin, I. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Year 2000 Computing Challenge: Readiness Improving Yet Essential Actions Remain to Ensure Delivery of Critical Services

Description: Testimony issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed the progress being made in addressing the year 2000 computing challenge, focusing on: (1) the federal government's progress and the challenges that remain in correcting its systems; (2) state and local government year 2000 issues; and (3) the readiness of key public infrastructure and economic sectors."
Date: August 17, 1999
Creator: United States. General Accounting Office.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Analysis of market penetration scenarios of clean coal technologies in China using the LLNL China Energy Model

Description: This paper presents the results of an analysis of the market penetration of Clean Coal Technologies in the electric utility market in China. The analysis is based on a model of the Chinese energy system developed at Lawrence Livermore National Laboratory. Under this model, the market penetration of a technology depends on the relative prices of all technologies in a market. The model assumes that for each technology there is a distribution of effective prices to the consumers in the market plac… more
Date: August 17, 1998
Creator: Lamont, A
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application of adaptive optics for controlling the NIF laser performance and spot size

Description: The National Ignition Facility (NIF) laser will use a 192-beam multi-pass architecture capable of delivering several MJ of UV energy in temporal pulse formats varying from sub-ns square to 20 ns precisely-defined high-contrast shapes. Each beam wavefront will be subjected to effects of optics inhomogeneities, figuring errors, mounting distortions, prompt and slow thermal effects from flashlamps, driven and passive air-path turbulence, and gravity-driven deformations. A 39-actuator intra-cavity … more
Date: August 17, 1998
Creator: Auerbach, J.; Bliss, E.; Henesian, M.; Lawson, J.; Manes, K.; Renard, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The effects of confinement and temperature on the shock sensitivity of solid explosives

Description: The effects of heavy steel confinement on the shock sensitivity of pressed solid high explosives heated to temperatures close to thermal explosion conditions were quantitatively measured. Cylindrical flyer plates accelerated by a 101 mm diameter gas gun impacted preheated explosive charges containing multiple embedded manganin pressure gauges. The high explosive compositions tested were LX-04-01 (85 wt.% HMX and 15 wt.% Viton A) heated to 170 ° C and LX-17 (92.5 wt.% TATB and 7.5 wt.% Kel-F… more
Date: August 17, 1998
Creator: Forbes, J W; Tarver, C M & Urtiew, Garcia, F
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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