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Mechanical design of a high field common coil magnet

Description: A common coil design for high field 2-in-1 accelerator magnets has been previously presented as a 'conductor-friendly' option for high field magnets applicable for a Very Large Hadron Collider. This paper presents the mechanical design for a 14 tesla 2-in-1 dipole based on the common coil design approach. The magnet will use a high current density Nb{sub 3}Sn conductor. The design addresses mechanical issues particular to the common coil geometry: horizontal support against coil edges, vertical… more
Date: March 18, 1999
Creator: Caspi, S.; Chow, K.; Dietderich, D.; Gourlay, S.; Gupta, R.; McInturff, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Enhanced Geothermal Systems (EGS) R&D Program

Description: The purpose of this workshop was to develop technical background facts necessary for planning continued research and development of Enhanced Geothermal Systems (EGS). EGS are geothermal reservoirs that require improvement of their permeability or fluid contents in order to achieve economic energy production. The initial focus of this R&D program is devising and testing means to extract additional economic energy from marginal volumes of hydrothermal reservoirs that are already producing com… more
Date: August 18, 1999
Creator: Entingh, Daniel J.
Partner: UNT Libraries Government Documents Department
open access

Oxidation Reactions of Ethane over Ba-Ce-O Based Perovskites

Description: Ethane oxidation reactions were studied over pure and Ca-, Mg-, Sr-, La-, Nd-, and Y-substituted BaCeO{sub 3} perovskites under oxygen limited conditions. Several of the materials, notably the Ca- and Y-substituted materials, show activity for complete oxidation of the hydrocarbon to CO{sub 2} at temperatures below 650 C. At higher temperatures, the oxidative dehydrogenation (ODH) to ethylene becomes significant. Conversions and ethylene yields are enhanced by the perovskites above the thermal … more
Date: August 18, 1999
Creator: Miller, James E.; Sault, Allen G.; Trudell, Daniel E.; Nenoff, Tina M.; Thoma, Steven G. & Jackson, Nancy B.
Partner: UNT Libraries Government Documents Department
open access

A machining parameter study to select best conditions for SPDT of large single-crystal silicon optics

Description: The interdependence of process parameters on diamond turning of single-crystal silicon is poorly understood. An experimental design technique based on methods of statistical analysis permits the determination of a specific parameter's influence and its co-dependence on other factors. This design technique enables the creation of an experimental matrix, considering all input parameters (surface velocity; feed rate; depth of cut; tool radius; tool rake/skew angle; cutting fluid), while substantia… more
Date: March 18, 1999
Creator: Carr, J W; Davis, P J; Haack, J K; Krulewich, D A; McClellan, M R & Zimmermann, M
Partner: UNT Libraries Government Documents Department
open access

Projected Consequence for Potential Sabotage Events Related to Spent Fuel Shipments

Description: There is a growing interest in understanding the potential consequences of malevolent acts against shipments of nuclear waste and/or material. Recently, Sandia National Laboratories (SNL) conducted a study' to evaluate the potential source terms available for release in a sabotage event for spent fuel shipments. Using these source terms, we developed an approach to assess the potential radiological consequences of the hypothesized events and to compare them to consequences of transportation acc… more
Date: August 18, 1999
Creator: Shyr, Lih-Jenn; Neuhauser, Sieglinde; Mills, Scott & Massey, Charles
Partner: UNT Libraries Government Documents Department
open access

Optimization of Micromachined Photon Devices

Description: The Oak Ridge National Laboratory has been instrumental in developing ultraprecision technologies for the fabrication of optical devices. We are currently extending our ultraprecision capabilities to the design, fabrication, and testing of micro-optics and MEMS devices. Techniques have been developed in our lab for fabricating micro-devices using single point diamond turning and ion milling. The devices we fabricated can be used in micro-scale interferometry, micro-positioners, micro-mirrors, a… more
Date: July 18, 1999
Creator: Datskos, P. G.; Datskou, I.; Evans, B. M., III & Rajic, S.
Partner: UNT Libraries Government Documents Department
open access

Combustion of TNT products in a confined explosion

Description: The effects of turbulent combustion of detonation products gases in a confined explosion are explored via laboratory experiments and high-resolution numerical simulations. The expanded products from the detonation of a TNT charge are rich in C and CO, which act as a fuel. When these hot gases mix with air, they are oxidized to CO2--thereby releasing 2482 Cal/g in addition to the 1093 Cal/g deposited by the detonation wave. In this case, the exothermic power is controlled by the turbulent mixing… more
Date: June 18, 1999
Creator: Ferguson, R E; Kuhl, A L & Oppenheim, A K
Partner: UNT Libraries Government Documents Department
open access

Carbon Sequestered, Carbon Displaced and the Kyoto Context

Description: The integrated system that embraces forest management, forest products, and land-use change impacts the global carbon cycle - and hence the net emission of the greenhouse gas carbon dioxide - in four fundamental ways. Carbon is stored in living and dead biomass, carbon is stored in wood products and landfills, forest products substitute in the market place for products made from other materials, and forest harvests can be used wholly or partially to displace fossil fuels in the energy sector. I… more
Date: April 18, 1999
Creator: Marland, G. & Schlamadinger, B.
Partner: UNT Libraries Government Documents Department
open access

The Program for Climate Model Diagnosis and Intercomparison Diagnostic System: Implementing a New Strategy Beyond the Atmospheric Model Intercomparison Project (AMIP)

Description: The Program for Climate Model Diagnosis and Intercomparison (PCMDI) was established in 1989 at the Lawrence Livermore National Laboratory (LLNL) with the principal mission to develop improved methods and tools for the diagnosis, validation and intercomparison of global climate models. The goal of the process is to eventually improve simulation of the regional climate effects of increasing greenhouse gases. In addition to comparing models, PCMDI continues to develop a modeling infrastructure by … more
Date: October 18, 1999
Creator: Potter, G.L.
Partner: UNT Libraries Government Documents Department
open access

Core-Level Satellites and Outer Core-Level Multiplet Splitting in Mn Model Compounds

Description: We report a systematic study of the Mn 2p, 3s and 3p core-level photoemission and satellite structures for Mn model compounds. Charge-transfer from the ligand state to the 3d metal state is observed and is distinguished by prominent shake-up satellites. We also observe that the Mn 3s multiplet splitting becomes smaller as the Mn oxidation state increases, and that 3s-3d electron correlation reduces the branching ratio of the 7S:5S states in the Mn 3s spectra. In addition, as the ligand electron… more
Date: October 18, 1999
Creator: Nelson, A. J.; Reynolds, J. G. & Roos, J. W.
Partner: UNT Libraries Government Documents Department
open access

Heating Distributions in the Target of the Spallation Neutron Source

Description: Detailed calculation of the heat distributions in the structural parts of the target (Hg) and the target itself were made with realistic proton profiles. Preliminary current profiles of the protons coming from the accumulator ring, calculated and parameterized by the Brookhaven National Laboratory (BNL), were used as input to the Monte Carlo code LAHET. Due to limitations of the present version of the LAHET code, the real source was approximated with a nest of elliptical rings (all with the sam… more
Date: November 18, 1999
Creator: Charlton, L.A. & Difilippo, F.C.
Partner: UNT Libraries Government Documents Department
open access

Position Sensitive Scintillation Neutron Detectors Using a Crossed-Fiber Optic Readout Array

Description: The Spallation Neutron Source (SNS) under construction at the Oak Ridge National Laboratory will be the most important new neutron scattering facility in the United States. Neutron scattering instruments for the SNS will require large area detectors with fast response (< 1 microsecond), high efficiency over a wide range of neutron energies (0.1 to 10 eV), and low gamma ray sensitivity. We are currently developing area neutron detectors based on a combination of 6 LiF/ZnS scintillator screens co… more
Date: July 18, 1999
Creator: Holcomb, David E.; Hutchinson, Donald P.; Ramsey, James A. & Richards, Roger K.
Partner: UNT Libraries Government Documents Department
open access

ROSE: The Design of a General Tool for the Independent Optimization of Object-Oriented Frameworks

Description: ROSE represents a programmable preprocessor for the highly aggressive optimization of C++ object-oriented frameworks. A fundamental feature of ROSE is that it preserves the semantics, the implicit meaning, of the object-oriented framework's abstractions throughout the optimization process, permitting the framework's abstractions to be recognized and optimizations to capitalize upon the added value of the framework's true meaning. In contrast, a C++ compiler only sees the semantics of the C++ la… more
Date: May 18, 1999
Creator: Davis, K.; Philip, B. & Quinlan, D.
Partner: UNT Libraries Government Documents Department
open access

Web-based document and content management with off-the-shelf software

Description: This, then, is the current status of the project: Since we made the switch to Intradoc, we are now treating the project as a document and image management system. In reality, it could be considered a document and content management system since we can manage almost any file input to the system such as video or audio. At present, however, we are concentrating on images. As mentioned above, my CRADA funding was only targeted at including thumbnails of images in Intradoc. We still had to modify In… more
Date: March 18, 1999
Creator: Schuster, J
Partner: UNT Libraries Government Documents Department
open access

Characterization of the LiSi/CsBr-LiBr-KBr/FeS(2) System for Potential Use as a Geothermal Borehole Power Source

Description: We are continuing to study the suitability of modified thermal-battery technology as a potential power source for geothermal borehole applications. Previous work focused on the LiSi/FeS{sub 2} couple over a temperature range of 350 C to 400 C with the LiBr-KBr-LiF eutectic, which melts at 324.5 C. In this work, the discharge processes that take place in LiSi/CsBr-LiBr-KBr eutectic/FeS{sub 2} thermal cells were studied at temperatures between 250 C and 400 C using pelletized cells with immobiliz… more
Date: October 18, 1999
Creator: GUIDOTTI, RONALD A. & REINHARDT, FREDERICK W.
Partner: UNT Libraries Government Documents Department
open access

Volatilization of Fission Products from Metallic Melts in the Melt-Dilute Treatment Technology Development for Al-Based DOE Spent Nuclear Fuels

Description: The melt-dilute treatment technology is being developed to facilitate the ultimate disposition of highly enriched Al-Base DOE spent nuclear fuels in a geologic repository such as that proposed for Yucca Mountain. Currently, approximately 28 MTHM is expected to be returned to the Savannah River Site from domestic and foreign research reactors. The melt-dilute treatment technology will melt the fuel assemblies to reduce their volume and alloys them with depleted uranium to isotopically dilute the… more
Date: November 18, 1999
Creator: Adams, T.
Partner: UNT Libraries Government Documents Department
open access

Vibratory response modeling and verification of a high precision optical positioning system.

Description: A generic vibratory-response modeling program has been developed as a tool for designing high-precision optical positioning systems. Based on multibody dynamics theory, the system is modeled as rigid-body structures connected by linear elastic elements, such as complex actuators and bearings. The full dynamic properties of each element are determined experimentally or theoretically, then integrated into the program as inertial and stiffness matrices. Utilizing this program, the theoretical and … more
Date: June 18, 1999
Creator: Barraza, J.; Kuzay, T.; Royston, T. J. & Shu, D.
Partner: UNT Libraries Government Documents Department
open access

Language interoperability for high-performance parallel scientific components

Description: With the increasing complexity and interdisciplinary nature of scientific applications, code reuse is becoming increasingly important in scientific computing. One method for facilitating code reuse is the use of components technologies, which have been used widely in industry. However, components have only recently worked their way into scientific computing. Language interoperability is an important underlying technology for these component architectures. In this paper, we present an approach t… more
Date: May 18, 1999
Creator: Elliot, N; Kohn, S & Smolinski, B
Partner: UNT Libraries Government Documents Department
open access

Estimating Wet Bulb Globe Temperature Using Standard Meteorological Measurements

Description: The heat stress management program at the Department of Energy''s Savannah River Site (SRS) requires implementation of protective controls on outdoor work based on observed values of wet bulb globe temperature (WBGT). To ensure continued compliance with heat stress program requirements, a computer algorithm was developed which calculates an estimate of WBGT using standard meteorological measurements. In addition, scripts were developed to generate a calculation every 15 minutes and post the res… more
Date: November 18, 1999
Creator: Hunter, C.H.
Partner: UNT Libraries Government Documents Department
open access

A future vision of nuclear material information systems

Description: To address the current and future needs for nuclear materials management and safeguards information, Lawrence Livermore National Laboratory envisions an integrated nuclear information system that will support several functions. The vision is to link distributed information systems via a common communications infrastructure designed to address the information interdependencies between two major elements: Domestic, with information about specific nuclear materials and their properties, and Intern… more
Date: July 18, 1999
Creator: Suski, N. & Wimple, C.
Partner: UNT Libraries Government Documents Department
open access

SMQIE: Challenges associated with a low frequency charge integrator and encoder for the CDF II Calorimeter

Description: The SMQIE is the newest member of the QIE family of integrated circuits. It has been developed specifically for the Shower Max Detector upgrade of the CDF Plug and Central Calorimeters at Fermilab. Like its predecessors, it converts charges over a wide dynamic range with a variable resolution. Unlike its predecessors it contains its own Flash, trigger delay pipeline and buffer area. Furthermore, it operates both at a lower frequency and with only a simple 5-volt power supply. The simultaneous r… more
Date: November 18, 1999
Creator: J. Hoff, G. Drake, A. Byon-Wagner, G. Foster and M. Lindgren
Partner: UNT Libraries Government Documents Department
open access

BSCCO superconductors : hole-like fermi surface and doping dependence of the gap function.

Description: We use the gradient of the energy-integrated angle resolved photoemission (ARPES) intensity in order to define precisely the Fermi surface (FS) in BSCCO superconductors. We show that, independent of the photon energy, the FS is a hole barrel centered at ({pi},{pi}), Then, the superconducting gap along the FS is precisely determined from ARPES measurements on over-doped and underdoped samples of Bi2212. As the doping decreases, the maximum gap increases, but the slope of the gap near the nodes d… more
Date: August 18, 1999
Creator: Campuzano, J. C.; Ding, H.; Fretwell, H. M.; Kadowaki, K.; Kaminski, A.; Mesot, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Optical Interferometry Diagnostics in Laser-Driven Equation of State Experiments

Description: We have developed and tested several optical interferometric diagnostics to measure preheat and shock velocity in high-pressure equation of state experiments on the Nova laser. Theory and practical application of interferometric measurement techniques with illustrative experimental results are presented.
Date: June 18, 1999
Creator: Cauble, R. C.; Celliers, P. M.; Collins, G. W.; Da Silva, L. B.; Gold, D. M.; Kalantar, D. H. et al.
Partner: UNT Libraries Government Documents Department
open access

Improved CO [lidar detector]

Description: A high sensitivity, CO{sub 2} lidar detector, based on recent advances in ultra-low noise, readout integrated circuits (ROIC), is being developed. This detector will combine a high speed, low noise focal plane array (FPA) with a dispersive grating spectrometer. The spectrometer will filter the large background flux, thereby reducing the limiting background photon shot noise. In order to achieve the desired low noise levels, the HgCdTe FPA will be cooled to {approximately}50K. High speed, short … more
Date: July 18, 1999
Creator: Jacobson, Phillip L.; Busch, George E.; Thompson, David C.; Remelius, Dennis K. & Wells, F. David
Partner: UNT Libraries Government Documents Department
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