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Development of continuous glass melting for production of Nd-doped phosphate glasses for the NIF and LMJ laser system

Description: The NIF and LMJ laser systems require about 3380 and 4752 Nd-doped laser glass slabs, respectively. Continuous laser glass melting and forming will be used for the first time to manufacture these slabs. Two vendors have been chosen to produce the glass: Hoya Corporation and Schott Glass Technologies. The laser glass melting systems that each of these two vendors have designed, built and tested are arguably the most advanced in the world. Production of the laser glass will begin on a pilot scale in the fall of 1999.
Date: August 14, 1998
Creator: Campbell, J. H.; Ficini-Dorn, G.; Hawley-Fedder, R.; McLean, M. J.; Suratwala, T. & Trombert, J. H.
Partner: UNT Libraries Government Documents Department

Evaluation of Gas Reburning & Low NOx Burners on a Wall Fired Boiler Performance and Economics Report Gas Reburning-Low NOx Burner System Cherokee Station Unit 3 Public Service Company of Colorado

Description: Under the U.S. Department of Energy's Clean Coal Technology Program (Round 3), a project was completed to demonstrate control of boiler NOX emissions and to a lesser degree, due to coal replacement, SO2 emissions. The project involved combining Gas Reburning with Low NOX Burners (GR-LNB) on a coal-fired electric utility boiler to determine if high levels of NOX reduction (70%) could be achieved. Sponsors of the project included the U.S. Department of Energy, the Gas Research Institute, Public Service Company of Colorado, Colorado Interstate Gas, Electric Power Research Institute, and the Energy and Environmental Research Corporation. The GR-LNB demonstration was performed on Public Service Company of Colorado's (PSCO) Cherokee Unit #3, located in Denver, Colorado. This unit is a 172 MW~ wall-fired boiler that uses Colorado Bituminous, low-sulfur coal. It had a baseline NOX emission level of 0.73 lb/106 Btu using conventional burners. Low NOX burners are designed to yield lower NOX emissions than conventional burners. However, the NOX control achieved with this technique is limited to 30-50%. Also, with LNBs, CO emissions can increase to above acceptable standards. Gas Reburning (GR) is designed to reduce NOX in the flue gas by staged fuel combustion. This technology involves the introduction of natural gas into the hot furnace flue gas stream. When combined, GR and LNBs minimize NOX emissions and maintain acceptable levels of CO emissions. A comprehensive test program was completed, operating over a wide range of boiler conditions. Over 4,000 hours of operation were achieved, providing substantial data. Measurements were taken to quantify reductions in NOX emissions, the impact on boiler equipment and operability and factors influencing costs. The GR-LNB technology achieved good NOX emission reductions and the goals of the project were achieved. Although the performance of the low NOX burners (supplied by others) was less than expected, ...
Date: July 1, 1998
Partner: UNT Libraries Government Documents Department

An Annotated Bibliography of HVDC Transmission and FACTS Devices, 1996-1997.

Description: This edition of the Annotated Bibliography of HVDC Transmission and FACTS Devices continues work begun in 1962 by the late Erik Bromberg, Bonneville Power Administration Librarian. His original bibliography covered the period 1932--1962. Subsequent editions were compiled by Bromberg, Val S. Lava, and Wayne Litzenberger, all of Bonneville Power Administration. Beginning with the 1991--1993 edition, the scope of the bibliography was expanded to include flexible ac transmission (FACTS) devices. This 1996--1997 edition also contains information for 1998. Preparation of the present edition took place primarily in May-June of 1998. All pertinent references have been included that were available to the editors at the time of preparation. Papers for the 1998 IEEE Winter and Summer Power Meetings and 1998 T and D Conference have been included. This edition contains the organizational affiliation of the first-named author as an aid to accessing the reference. Unfortunately, space limitations prevented the inclusion of the affiliations of all authors. Some minor editorial changes have been made to abstracts to ensure consistency in style and syntax.
Date: June 1, 1998
Creator: Litzenberger, Wayne H.; Varma, Rajiv K. & Flanagan, John D.
Partner: UNT Libraries Government Documents Department

Integrated operations of the National Ignition Facility (NIF) optical pulse generation development system

Description: We describe the Optical Pulse Generation (OPG) testbed, which is the integration of the MOR and Preamplifier Development Laboratories. We use this OPG testbed to develop and demonstrate the overall capabilites of the NIF laser system front end. We will present the measured energy and power output, temporal and spatial pulse shaping capability, FM bandwidth and dispersion for beam smoothing, and measurements of the pulse-to-pulse power variation of the OPG system and compare these results with the required system performance specifications. We will discuss the models that are used to predict the system performance and how the OPG output requirements flowdown to the subordinate subsystems within the OPG system.
Date: July 31, 1998
Creator: Browning, D.; Crane, J. K.; Dane, C. B.; Hackel; Henesian, M.; Hopps, N. W. et al.
Partner: UNT Libraries Government Documents Department

Recent developments on the high power ECH installation at the DIII-D tokamak

Description: The 110 GHz gyrotron installation on the DIII-D tokamak has been upgraded to three tubes in the megawatt class with plans for further upgrades. The latest addition uses a diamond output window. The report describes the installation, plans, and experimental results to date.
Date: September 1, 1998
Creator: Lohr, J.; Ponce, D.; Callis, R.W.; Doane, J.L.; Ikezi, H. & Moeller, C.P.
Partner: UNT Libraries Government Documents Department

Thin-film characterization and flaw detection. Final report, February 1, 1993--November 31, 1997

Description: The objectives were to determine the elastic constants of thin films deposited on substrates, to measure residual stress and to detect and characterize defects in thin film substrate configurations. There are many present and potential applications of configurations consisting of a thin film deposited on a substrate. Thin films that are deposited to improve the hardness and/or the thermal properties of surfaces were of principal interest in this work. Thin film technology does, however, also include high {Tc} superconductor films, films for magnetic recording, superlattices and films for band-gap engineering and quantum devices. The studies that were carried out on this project also have relevance to these applications. Both the film and the substrate are generally anisotropic. A line-focus acoustic microscope has been used to measure the speed of surface acoustic waves (SAW) in the thin film/substrate system. This microscope has unique advantages for measurements in anisotropic media. Analytical and numerical techniques have been employed to extract the desired information on the thin film from the measured SAW data. Results include: (1) analytical and numerical techniques for the direct problem and for inverse methods; (2) measurements of homogeneous and superlattice film constants; (3) investigation of the effect of surface roughness and (4) measurements of residual stresses.
Date: February 25, 1998
Creator: Achenbach, J.D.
Partner: UNT Libraries Government Documents Department

Freedom to mix vulnerable offensive and defensive forces

Description: The freedom to mix offense and defense to expand without diminishing either side`s second strike capability is shown to be counterproductive at large numbers of missiles; effective at intermediate numbers; and progressively less effective at modest numbers. Solutions are less stable for large second strikes.
Date: September 1, 1998
Creator: Canavan, G. H.
Partner: UNT Libraries Government Documents Department

Interaction between point defects and edge dislocation in BCC iron

Description: We present results of atomistic simulations of the interaction between self interstitial atoms and vacancies with edge dislocations in BCC iron. The calculations are carried out using molecular dynamics with an energy minimization scheme based on the quasi-Newton approach and use the Finnis-Sinclair interatomic potential for BCC iron developed by Ackland et al. Large anisotropy in the strain field of self interstitials is observed and it causes strong interaction with edge dislocations even when the defect is located on the dislocation glide plane. For vacancies, the relaxation volume is smaller and much more isotropic, which results in a far weaker interaction with the dislocation. A temperature dependent capture radius for vacancies and self interstitials is extracted from the simulations. The difference between the capture radii of vacancies and self interstitials is used to define the sink strength of the dislocation. Large deviations are observed from the predictions of elasticity based on treating point defects as isotropic dilatational centers. Further, the capture radius of edge dislocations in BCC iron is observed to be small and is of the order of l-3 nm for self interstitials.
Date: October 12, 1998
Creator: Diaz de la Rubia, T. & Shastry, V.
Partner: UNT Libraries Government Documents Department

Improved methods for water shutoff. Final technical progress report, October 1, 1997--September 30, 1998

Description: In the United States, more than 20 billion barrels of salt water are produced each year during oilfield operations. A tremendous economic incentive exists to reduce water production if that can be accomplished without significantly sacrificing hydrocarbon production. This three-year research project had three objectives. The first objective was to identify chemical blocking agents that will (a) during placement, flow readily through fractures without penetrating significantly into porous rock and with screening out or developing excessive pressure gradients and (b) at a predictable and controllable time, become immobile and resistant breakdown upon exposure to moderate to high pressure gradients. The second objective was to identify schemes that optimize placement of the above blocking agents. The third objective was to explain why gels and other chemical blocking agents reduce permeability to one phase (e.g., water) more than that to another phase (e.g., oil or gas). The authors also wanted to identify conditions that maximize this phenomenon. This project consisted of three tasks, each of which addressed one of the above objectives. This report describes work performed during the third and final period of the project. During this three-year project, they: (1) Developed a procedure and software for sizing gelant treatments in hydraulically fractured production wells; (2) Developed a method (based on interwell tracer results) to determine the potential for applying gel treatments in naturally fractured reservoirs; (3) Characterized gel properties during extrusion through fractures; (4) Developed a method to predict gel placement in naturally fractured reservoirs; (5) Made progress in elucidating the mechanism for why some gels can reduce permeability to water more than that to oil; (6) Demonstrated the limitations of using water/oil ratio diagnostic plots to distinguish between channeling and coning; and (7) Proposed a philosophy for diagnosing and attacking water-production problems.
Date: October 1, 1998
Creator: Seright, R. S.; Liang, J. T.; Schrader, R.; Hagstrom, J., II; Liu, J. & Wavrik, K.
Partner: UNT Libraries Government Documents Department

CAVE: the design of a precision metrology instrument for studying performance of KDP crystals

Description: A device has been developed to measure the frequency conversion performance of large aperture potassium dihydrogen phosphate (KDP) crystals. Third harmonic generation using ICDP is critical to the function of the National Ignition Facility (NIF) laser. The crystals in the converter can be angularly or thermally tuned but are subject to larger aperture inhomogeneities that are functions of growth manufacturing and - mounting. The CAVE (Crystal Alignment Verification Equipment) instrument scans the crystals in a thermally and mechanically controlled environment to determine the local peak tuning angles. The CAVE can then estimate the optimum tuning angle and conversion efficiency over the entire aperture. Coupled with other metrology techniques, the CAVE will help determine which crystal life-cycle components most affect harmonic conversion.
Date: March 30, 1998
Creator: Hibbard, R.L., LLNL
Partner: UNT Libraries Government Documents Department

Improved recovery demonstration for Williston Basin carbonates. Final report

Description: The purpose of this project was to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, and methods for improved completion efficiency. The investigations and demonstrations were focussed on Red River and Ratcliffe reservoirs in the Williston Basin within portions of Montana, North Dakota and South Dakota. Both of these formations have been successfully explored with conventional 2-dimensional (2D) seismic. Improved reservoir characterization utilizing 3-dimensional (3D) seismic was investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterizations were integrated with geological and engineering studies. The project tested lateral completion techniques, including high-pressure jetting lance technology and short-radius lateral drilling to enhance completion efficiency. Lateral completions should improve economics for both primary and secondary oil where low permeability is a problem and higher-density drilling of vertical infill wells is limited by drilling cost. New vertical wells were drilled to test bypassed oil in ares that were identified by 3D seismic. These new wells are expected to recover as much or greater oil than was produced by nearby old wells. The project tested water injection through vertical and horizontal wells in reservoirs where application of waterflooding has been limited. A horizontal well was drilled for testing water injection. Injection rates were tested at three times that of a vertical well. This demonstration well shows that water injection with horizontal completions can improve injection rates for economic waterflooding. This report is divided into two sections, part 1 covers the Red River and part 2 covers the Ratcliffe. Each part summarizes integrated reservoir characterizations and outlines methods for targeting by-passed oil reserves in the respective formation and locality.
Date: July 1, 1998
Creator: Sippel, M.A.
Partner: UNT Libraries Government Documents Department

Infrasonic observation of earthquakes

Description: Infrasound signals generated by earthquakes have been detected at arrays operated by the Los Alamos National Laboratory. Three modes of propagation are possible and all have been observed by the authors. The observations suggest that regions remote from the epicenters are excited and may serve as secondary source regions. A relation is found between the normalized peak amplitudes and the seismic magnitudes.
Date: December 31, 1998
Creator: Mutschlecner, J.P. & Whitaker, R.W.
Partner: UNT Libraries Government Documents Department

An integral equation based computer code for high-gain free-electron lasers

Description: A computer code for gain optimization of high-gain free-electron lasers (FELs) is described. The electron motion is along precalculated period-averaged trajectories, and the finite-emittance electron beam is represented by a set of thin partial beams. The radiation field amplitudes are calculated at these thin beams only. The system of linear integral equations for these field amplitudes and the Fourier harmonics of the current of each thin beam is solved numerically. The code is aimed for design optimization of high-gain short-wavelength FELs with nonideal magnetic systems (breaks between undulators with quadrupoles and magnetic bunchers; field and steering errors). Both self-amplified spontaneous emission (SASE) and external input signal options can be treated. A typical run for a UV FEL, several gain lengths long, takes only one minute on a Pentium II personal computer (333 MHz) which makes it possible to run the code in optimization loops. Results for the Advanced Photon Source FEL project are presented.
Date: September 1, 1998
Creator: Dejus, R.J.; Shevchenko, O.A. & Vinokurov, N.A.
Partner: UNT Libraries Government Documents Department

High priority tank sampling and analysis report

Description: In July 1993, the Defense Nuclear Facilities Board issued Recommendation 93-5 (Conway 1993) which noted that there was insufficient tank waste technical information and the pace to obtain it was too slow to ensure that Hanford Site wastes could be safely stored, that associated operations could be conducted safely, and that future disposal data requirements could be met. In response, the US Department of Energy, in May 1996, issued Revision 1 of the Recommendation 93-5 Implementation Plan (DOE-RL 1996). The Implementation Plan presented a modified approach to achieve the original plan`s objectives, concentrating on actions necessary to ensure that wastes can be safely stored, that operations can be safely conducted, and that timely characterization information for the tank waste Disposal Program could be obtained. The Implementation Plan proposed 28 High Priority tanks for near term core sampling and analysis, which along with sampling and analysis of other non-High Priority tanks, could provide the scientific and technical data to confirm assumptions, calibrate models, and.measure safety related phenomenology of the waste. When the analysis results of the High Priority and other-tank sampling were reviewed, it was expected that a series of 12 questions, 9 related to safety issues and 3 related to planning for the disposal process, should be answered allowing key decisions to be made. This report discusses the execution of the Implementation Plan and the results achieved in addressing the questions. Through sampling and analysis, all nine safety related questions have been answered and extensive data for the three disposal planning related questions have been collected, allowing for key decision making. Many more tanks than the original 28 High Priority tanks identified in the Implementation Plan were sampled and analyzed. Twenty-one High Priority tanks and 85 other tanks were core sampled and used to address the questions. Thirty-eight additional tanks ...
Date: March 24, 1998
Creator: Brown, T.M.
Partner: UNT Libraries Government Documents Department

Speech coding

Description: Speech is the predominant means of communication between human beings and since the invention of the telephone by Alexander Graham Bell in 1876, speech services have remained to be the core service in almost all telecommunication systems. Original analog methods of telephony had the disadvantage of speech signal getting corrupted by noise, cross-talk and distortion Long haul transmissions which use repeaters to compensate for the loss in signal strength on transmission links also increase the associated noise and distortion. On the other hand digital transmission is relatively immune to noise, cross-talk and distortion primarily because of the capability to faithfully regenerate digital signal at each repeater purely based on a binary decision. Hence end-to-end performance of the digital link essentially becomes independent of the length and operating frequency bands of the link Hence from a transmission point of view digital transmission has been the preferred approach due to its higher immunity to noise. The need to carry digital speech became extremely important from a service provision point of view as well. Modem requirements have introduced the need for robust, flexible and secure services that can carry a multitude of signal types (such as voice, data and video) without a fundamental change in infrastructure. Such a requirement could not have been easily met without the advent of digital transmission systems, thereby requiring speech to be coded digitally. The term Speech Coding is often referred to techniques that represent or code speech signals either directly as a waveform or as a set of parameters by analyzing the speech signal. In either case, the codes are transmitted to the distant end where speech is reconstructed or synthesized using the received set of codes. A more generic term that is applicable to these techniques that is often interchangeably used with speech coding is the ...
Date: May 8, 1998
Creator: Ravishankar, C., Hughes Network Systems, Germantown, MD
Partner: UNT Libraries Government Documents Department

Natural Circulation in the Blanket Heat Removal System During a Loss-of-Pumping Accident (LOFA) Based on Initial Conceptual Design

Description: A transient natural convection model of the APT blanket primary heat removal (HR) system was developed to demonstrate that the blanket could be cooled for a sufficient period of time for long term cooling to be established following a loss-of-flow accident (LOFA). The particular case of interest in this report is a complete loss-of-pumping accident. For the accident scenario in which pumps are lost in both the target and blanket HR systems, natural convection provides effective cooling of the blanket for approximately 68 hours, and, if only the blanket HR systems are involved, natural convection is effective for approximately 210 hours. The heat sink for both of these accident scenarios is the assumed stagnant fluid and metal on the secondary sides of the heat exchangers.
Date: October 7, 1998
Creator: Hamm, L.L.
Partner: UNT Libraries Government Documents Department

Closure Welding Design and Justification for Canister S00645 (Bent Flange)

Description: This report provides the design basis and justification for a closure welding technique using the manual Gas Tungsten Are Welding (GTAW) process. Other aspects affecting closure of Canister S00645, e.g., shielding, facility and administrative requirements, etc., are addressed elsewhere.
Date: December 21, 1998
Creator: Cannell, G.R.
Partner: UNT Libraries Government Documents Department

Summary of uncertainty estimation results for Hanford tank chemical and radionuclide inventories

Description: The exact physical and chemical nature of 55 million gallons of radioactive waste held in 177 underground waste tanks at the Hanford Site is not known in sufficient detail to support safety, retrieval, and immobilization missions. The Hanford Engineering Analysis Best-Basis team has made point estimates of the inventories in each tank. The purpose of this study is to estimate probability distributions for each of the analytes and tanks for which the Hanford Best-Basis team has made point estimates. Uncertainty intervals can then be calculated for the Best-Basis inventories and should facilitate the cleanup missions. The methodology used to generate the results published in the Tank Characterization Database (TCD) and summarized in this paper is based on scientific principles, sound technical knowledge of the realities associated with the Hanford waste tanks, the chemical analysis of actual samples from the tanks, the Hanford Best-Basic research, and historical data records. The methodology builds on research conducted by Pacific Northwest National Laboratory (PNNL) over the last few years. Appendix A of this report summarizes the results of the study. The full set of results (in percentiles, 1--99) is available through the TCD, (http://twins.pnl.gov:8001).
Date: September 1, 1998
Creator: Ferryman, T.A.; Amidan, B.G. & Chen, G.
Partner: UNT Libraries Government Documents Department

External Q studies for APT superconducting cavity couplers

Description: Coupling coefficients for the APT superconducting cavity couplers have been predicted using an improvement of the method previously developed for the French Trispal project. The authors here present the method and a proof of the formula used to compute the external Q. Measurements on a single-cell copper cold model exhibited a very good agreement against simulation. Then, they established that the original coupler design lead to an insufficient coupling in {beta} = 0.64 cavities. Different solutions were proposed to fix this problem, like combining impedance discontinuities in the line and an off-centered disc end tip. Finally, it was decided to increase the beam tube diameter though it has some influence on the cavity end-cell performance.
Date: December 31, 1998
Creator: Balleyguier, P.
Partner: UNT Libraries Government Documents Department

Tank 241-Z-361 process and characterization history

Description: An Unreviewed Safety Question (Wagoner, 1997) was declared based on lack of adequate authorization basis for Tank 241-Z-361 in the 200W Area at Hanford. This document is a summary of the history of Tank 241-Z-361 through December 1997. Documents reviewed include engineering files, laboratory notebooks from characterization efforts, waste facility process procedures, supporting documents and interviews of people`s recollections of over twenty years ago. Records of transfers into the tank, past characterization efforts, and speculation were used to estimate the current condition of Tank 241-Z-361 and its contents. Information about the overall waste system as related to the settling tank was included to help in understanding the numbering system and process relationships. The Plutonium Finishing Plant was built in 1948 and began processing plutonium in mid-1949. The Incinerator (232-Z) operated from December 1961 until May 1973. The Plutonium Reclamation Facility (PRF, 236-Z) began operation in May 1964. The Waste Treatment Facility (242-Z) operated from August 1964 until August 1976. Waste from some processes went through transfer lines to 241-Z sump tanks. High salt and organic waste under normal operation were sent to Z-9 or Z-18 cribs. Water from the retention basin may have also passed through this tank. The transfer lines to 241-Z were numbered D-4 to D-6. The 241-Z sump tanks were numbered D-4 through D-8. The D-4, 5, and 8 drains went to the D-6 sump tank. When D-6 tank was full it was transferred to D-7 tank. Prior to transfer to cribs, the D-7 tank contents was sampled. If the plutonium content was analyzed to be more than 10 g per batch, the material was (generally) reprocessed. Below the discard limit, caustic was added and the material was sent to the cribs via the 241-Z-361 settling tank where solids settled out and the liquid overflowed by gravity ...
Date: August 6, 1998
Creator: Jones, S.A.
Partner: UNT Libraries Government Documents Department

Energy and momentum conserving algorithms for rigid body contact

Description: Energy-momentum conserving methods are developed for rigid body dynamics with contact. Because these methods are unconditionally stable, they are not time step dependent and, hence, are well suited for incorporation into structural mechanics finite element codes. Both penalty and Lagrange multiplier methods are developed herein and are the extension of the energy-momentum conserving integration schemes for rigid bodies given by Simo and Wong [1].
Date: April 9, 1998
Creator: Puso, M.A. & Zywicz, E.
Partner: UNT Libraries Government Documents Department