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[Texas Stonewall Democrats invoice and post-it note]

Description: An invoice from the Texas Triangle to Texas Stonewall Democrats of $1,210.00 on September 20, 2000. There is also a post-it note from Michael Milliken to Al Daniels regarding a check for $1,210.00 to Stonewall Democrats.
Date: September 20, 2000
Partner: UNT Libraries Special Collections
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Fabrication of Efficient, Large Aperture Transmission Diffraction Gratings by Ion-Beam Etching

Description: The utilization of high-power short pulse laser employing chirped-pulse amplification (CPA) for material processing and inertial confinement research is widely increasing. The performance of these high-power CPA laser system continues to be limited by the ability of the pulse compression gratings to hold up to the high-average-power or high-peak-power of the laser. Pulse compression gratings used in transmission and fabricated out of bulk fused silica have intrinsically the highest laser damage threshold when compared with metal or multilayer dielectric gratings that work in reflection. LLNL has developed processing capability to produce high efficiency fused silica transmission gratings at sizes useful to future Petawatt-class systems, and has demonstrated high efficiency at smaller aperture. This report shows that fused silica diffraction exhibiting >95% efficiency into the -1 diffraction order in transmission (90{sup o} deflection of the incident light, at an incidence angle of 45{sup o} to the grating face). The microstructure of this grating consisted of grooves ion-beam etched to a depth of 1.6 microns with a pitch of 0.75 microns, using a holographically produced photoresist mask that was subsequently stripped away in significance to the fabrication of the small scale high efficiency grating was the development of the processing technology and infrastructure for production of such gratings at up to 65 cm diameter. LLNL is the currently the only location in the world with the ability to coat, interferometrically expose, and ion etch diffractive optics at this aperture. Below, we describe the design, fabrication, performance and, the scaleup process for a producing a high-efficiency transmission grating on a 65 cm fused silica substrate.
Date: September 14, 2000
Creator: Nguyen, H T; Bryan, S R; Britten, J A & Perry, M D
Partner: UNT Libraries Government Documents Department
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Alternate Approach to the 239Pu(n,2n) Cross Section

Description: Using existing experimental data for neutron-induced total, elastic, inelastic, reaction and fission cross sections, as well as results from nuclear model calculations and evaluations from nuclear reaction data libraries, we derived an estimate for the cross sections for the {sup 235}U(n,2n) and {sup 239}Pu(n,2n) reactions for the neutron energy range from threshold to approximately 12 MeV. In effect, our approach is based on subtracting the fission and inelastic cross sections from the total reaction cross section where the difference is expected to yield the (n,2n) cross section. In addition to this subtraction approach, a ratio method and a differential method have also been explored. For {sup 235}U(n,2n), as a test case, we arrive at a cross section consistent with previous measurements, and for {sup 239}Pu(n,2n) we obtain a peak value of 400 {+-} 60 mb for the incident neutron energy range of 10 {le} E{sub n} {le} 12 MeV.
Date: September 1, 2000
Creator: Anderson, J. D.; Bauer, R. W.; Becker, J. A.; Dietrich, F. S. & McNabb, D. P.
Partner: UNT Libraries Government Documents Department
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Effects of Fire on Soil Seed Banks on the Hanford Site

Description: The Hanford wildfire in the summer of 2000 destroyed much of the vegetation on the Hanford Site, often resulting in soil erosion and dust storms. The 200 W Area has been affected by dust storms, and a re-vegetation project has been planned for the area to the west, the source of much of the dust. To determine if the seed bank in this area had been damaged by the fire, inhibiting natural re-growth, soil samples were collected from three burned areas and watered to see how much seedling emergence would occur. The soil was then sifted for grass seeds and the seeds examined for signs of fire damage. From this data it was concluded that significant damage to the seed bank probably occurred in the 200 West Expansion Area, and slight damage may have occurred primarily to monocot seeds in the seed banks farther west.
Date: September 8, 2000
Creator: Baker, Sarah E.
Partner: UNT Libraries Government Documents Department
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Fissile Materials Disposition Program Plutonium Immobilization Project Baseline Formulation

Description: Since 1994 Lawrence Livermore National Laboratory (LLNL), with the help of several other laboratories and university groups, has been the lead laboratory for the Plutonium Immobilization Project (PIP). This involves, among other tasks, the development of a formulation and a fabrication process for a ceramic to be used in the immobilization of excess weapons-usable plutonium. This report reviews the history of the project as it relates to the development of the ceramic form. It describes the sample test plan for the pyrochlore-rich ceramic formulation that was selected, and it specifies the baseline formulation that has been adopted. It also presents compositional specifications (e.g. precursor compositions and mixing recipes) and other form and process specifications that are linked or potentially linked to the baseline formulation.
Date: September 1, 2000
Creator: Ebbinghaus, Bartley B.; Armantrout, Guy A.; Gray, Leonard; Herman, Connie C.; Shaw, Henry F. & Van Konynenburg, Richard A.
Partner: UNT Libraries Government Documents Department
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Measurement of Several 239Pu(n,xn) Partial (gamma)-Ray Cross Sections for x(<=)3 Using GEANIE at LANSCE/WNR

Description: Previous experimental efforts to measure the {sup 239}Pu(n,2n) reaction cross section have relied on the detection of evaporated neutrons [Mat72,Fre85]. These efforts were hampered by the presence of the large ({sigma} {approx} 2 barns) neutron-induced fission channel which produces on average 3-4 neutrons [How71]. This paper is one of three manuscripts that document an effort to determine the {sup 239}Pu(n,2n) channel cross section using the GErmanium Array for Neutron Induced Excitations (GEANIE) spectrometer [Bec97] at the Los Alamos Neutron Science Center/Weapons Neutron Research (LANSCE/WNR) [Lis90] facility. In this document we report the measurement of several {sup 239}Pu(n,xn{gamma}){sup 240-x}Pu partial cross sections. The other two papers report results for a parallel proof-of-principle experiment using a {sup 235}U target as a surrogate for {sup 239}Pu [Youn00] and a detailed calculation and measurement of the efficiency of the GEANIE spectrometer [McN00]. Results from these two works are frequently referred to in this paper. A later report from Becker et al. will use the partial (n2n{gamma}) cross sections reported here, together with the predictions of the GNASH [Cha99,Cha00] and IDA [Ros99] reaction models, to extract a total cross section for the (n,2n) channel. The results of three experiments are reported here. Two were carried out in 1998 using a 0.010 inch (referred to as ''thin'') and 0.020 inch (referred to as ''thick'') {sup 239}Pu target. The remaining one was run in 1999 using the same thin target. This work is being carried out in parallel with a similar effort to measure (n,xn{gamma}) cross sections on a {sup 235}U target being analyzed by Younes et al., [You00]. This experiment was performed using the same {gamma}-ray spectrometer and a similar analysis approach, thereby allowing a detailed comparison between the two data sets and a check on the techniques used. The report is comprised of three portions. …
Date: September 1, 2000
Creator: Bernstein, L A; Becker, J A; Garrett, P E; Hauschild, K; McGrath, C A; McNabb, D P et al.
Partner: UNT Libraries Government Documents Department
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New Mid-IR Lasers Based on Rare-Earth-Doped Sulfide and Chloride Materials

Description: Applications in remote-sensing and military countermeasures have driven a need for compact, solid-state mid-IR lasers. Due to multi-phonon quenching, non-traditional hosts are needed to extend current solid-state, room-temperature lasing capabilities beyond {approx} 4 {micro}m. Traditional oxide and fluoride hosts have effective phonon energies in the neighborhood of 1000 cm{sup -1} and 500 cm{sup -1}, respectively. These phonons can effectively quench radiation above 2 and 4 {micro}m, respectively. Materials with lower effective phonon energies such as sulfides and chlorides are the logical candidates for mid-IR (4-10 {micro}m) operation. In this report, laser action is demonstrated in two such hosts, CaGa{sub 2}S{sub 4} and KPb{sub 2}Cl{sub 5}. The CaGa{sub 2}S{sub 4}:Dy{sup 3+} laser operating at 4.3 {micro}m represents the first sulfide laser operating beyond 2 {micro}m. The KPb{sub 2}Cl{sub 5}:Dy{sup 3+} laser operating at 2.4 {micro}m represents the first operation of a chloride-host laser in ambient conditions. Laser action is also reported for CaGa{sub 2}S{sub 4}:Dy{sup 3+} at 2.4 {micro}m, CaGa{sub 2}S{sub 4}:Dy{sup 3+} at 1.4 {micro}m, and KPb{sub 2}Cl{sub 5}:Nd{sup 3+} at 1.06 {micro}m. Both host materials have been fully characterized, including lifetimes, absorption and emission cross sections, radiative branching ratios, and radiative quantum efficiencies. Radiative branching ratios and radiative quantum efficiencies have been determined both by the Judd-Ofelt method (which is based on absorption measurements), and by a novel method described herein which is based on emission measurements. Modeling has been performed to predict laser performance, and a new method to determine emission cross section from slope efficiency and threshold data is developed. With the introduction and laser demonstration of rare-earth-doped CaGa{sub 2}S{sub 4} and KPb{sub 2}Cl{sub 5}, direct generation of mid-IR laser radiation in a solid-state host has been demonstrated. In KPb{sub 2}Cl{sub 5}, predictions indicate that laser operation to 9 {micro}m may be possible, a wavelength previously considered …
Date: September 1, 2000
Creator: Nostrand, M
Partner: UNT Libraries Government Documents Department
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Intercomparison of present and future climates simulated by coupled ocean-atmosphere GCMs

Description: We present an overview of results from the most recent phase of the Coupled Model Intercomparison Project (CMIP). This phase of CMIP has archived output from both unforced (''control run'') and perturbed (1% per year increasing atmospheric carbon dioxide) simulations by 15 modern coupled ocean-atmosphere general circulation models. The models are about equally divided between those employing and those not employing ad hoc flux corrections at the ocean-atmosphere interface. The new generation of non-flux-connected control runs are nearly as stable and agree with observations nearly as well as the flux-corrected models. This development represents significant progress in the state of the art of climate modeling since the Second (1995) Scientific Assessment Report of the Intergovernmental Panel on Climate Change (IPCC; see Gates et al. 1996). From the increasing-CO{sub 2} runs, we find that differences between different models, while substantial, are not as great as would be expected from earlier assessments that relied on equilibrium climate sensitivity.
Date: September 6, 2000
Creator: Covey, C; AchutaRao, K M & Lambert, S J
Partner: UNT Libraries Government Documents Department
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Mineralogical, Chemical, and Isotopic Characterization of Fracture-Coating Minerals in Borehole Samples from Western Pahute Mesa and Oasis Valley, Nevada

Description: This report summarizes the results of a mineralogical and geochemical investigation of fracture-coating phases obtained from archived borehole core and cuttings samples from the western Pahute Mesa-Oasis Valley region. The objective is to provide data needed to validate UGTA flow and transport models for this region. Fracture-lining minerals were characterized using micrographic techniques (SEM-EDS), and selected calcite samples were analyzed for their stable isotope ({sup 13}C/{sup 12}C and {sup 18}O/{sup 16}O) and rare earth element (REE) abundances. The main conclusions are as follows: (1) The distribution of fracture-lining mineral phases is a function of primary rock type, the style and degree of syn-depositional alteration, effects of post-depositional hydrothermal alteration, and fracture location relative to recharge waters (in the unsaturated zone) or through going groundwater (in the saturated zone). (2) Fracture-lining minerals within the welded tuff aquifers (principally the Timber Mountain and Paintbrush Tuffs) are characterized by the assemblage calcite + chalcedony + Fe- and Mn-oxyhydroxides + mixed illite/smectite (in approximate decreasing order of abundance). The predominant mode of host rock alteration is quartzofeldspathic. (3) Interbedded rhyolitic lava flow aquifers are characterized by the fracture-lining assemblage chalcedony + mixed illite/smectite + Fe- and Mn-oxyhydroxides {+-} calcite {+-} quartz {+-} K-feldspar (in approximate decreasing order of abundance). These include lava flow aquifers from the Thirsty Canyon, Beatty Wash, Paintbrush, and Quartz Mountain groups. The predominant mode of host rock alteration is quartzofeldspathic. (4) Fracture-lining zeolite minerals are abundant only within one of the basaltic lava flow aquifers (Trachyte of Ribbon Cliff) where they occur with chalcedony + calcite + clay minerals. (5) Stable isotope analyses ({sup 13}C/{sup 12}C and {sup 18}O/{sup 16}O) of secondary calcite samples were used to deduce the origin and temperature of formation of the calcite. These data are also useful for constraining the geochemical evolution of dissolved inorganic …
Date: September 1, 2000
Creator: Benedict, F C; Rose, T P & Zhou, X
Partner: UNT Libraries Government Documents Department
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Methodology for shrapnel and debris impact and an assessment for experiment planned for NIF

Description: This report servers two purposes: first, it suggests a detailed methodology for assessing the debris-shield impacts of experiments planned to be conducted on NIF; second, it describes the most thorough examination of an experiment's impacts on NIF done to date. In addition, we comment on what needs exist for further improvements in computational capabilities. An overview of the methodology is shown. There are three parts: Experiment Design, Experiment Impacts, and Optics Impacts.
Date: September 29, 2000
Creator: Eder, D C; Tobin, M T; Jones, O S; Braun, D G; Shaw, M J; Tokheim, R E et al.
Partner: UNT Libraries Government Documents Department
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Search for simultaneous optical counterparts of gamma-ray bursts

Description: Gamma Ray Bursts (GRBs) are brief, randomly located, releases of gamma-ray energy from unknown celestial sources that occur almost daily. The study of GRBs has undergone a revolution in the past three years due to an international effort of follow-up observations made possible by the instantaneous distribution of reliable GRB coordinate information over the internet provided by NASA's GCN (GRB Coordinates Network). The 3-year LDRD project described here, done in collaboration with the workers responsible for the GCN, was the very first serious system to actively utilize the GCN and thus played a major role in the development of the GCN and the dramatic increase in our understanding of GRBs. The scientific objective of this project was to measure the intensity of any prompt visible radiation accompanying the gamma-ray emission utilizing a small but sensitive robotic telescope that responded to GCN triggers by rapidly taking images of the GCN error box. The instrument developed for this project, LOTIS, was the first of its kind, and the longest running, collecting data on over 75 GRBs during its 3 year running period. The results of LOTIS and the other follow-up programs have now shown that GRBs are at cosmological distances and interact with surrounding material as described by the ''fireball model.'' Visible, prompt, optical counterparts have only been seen in one case and are therefore very rare or much dimmer than the sensitivity of the current instruments. This places numerical limits on the surrounding matter density, and other physical parameters in the GRB environment. A much more sensitive instrument, Super-LOTIS, has been developed for operation at Kitt-Peak.
Date: September 5, 2000
Creator: Park, H. S.; Porrata, R. A.; Bionta, R. M. & Williams, G. G.
Partner: UNT Libraries Government Documents Department
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Environmental Report 1999 Data Supplement

Description: This Data Supplement to the Lawrence Livermore National Laboratory's (LLNL's) annual ''Environmental Report 1999'' was prepared for the U.S. Department of Energy. The main volume is intended to provide all information on LLNL's environmental impact and compliance activities that is of interest to most readers. The Data Supplement supports main volume summary data and is essentially a detailed data report that provides individual data points, where applicable. Some summary data are also included in the Data Supplement, and more detailed accounts are given of sample collection and analytical methods. The two volumes are organized in a parallel fashion to aid the reader in cross-referencing between them. This supplement includes more detailed information to support the nine chapters in the main volume that cover monitoring of air, air effluent, sewerable water, surface water, ground water, soil and sediment, vegetation and foodstuff, environmental radiation, and quality assurance. The other five chapters in the main volume have no supporting information in the Data Supplement. As in our previous annual reports, data are presented in Systeme International (SI) units. In particular, the primary units used for radiological results are becquerels and sieverts for activity and dose, with curies and rem used secondarily (1 Bq = 2.7 x 10{sup -11} Ci; 1 Sv = 100 rem).
Date: September 1, 2000
Creator: Larson, J. M.; Biermann, A. H.; Harrach, R. J.; Althouse, P. E.; Bertoldo, N. A.; Blake, R. G. et al.
Partner: UNT Libraries Government Documents Department
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Gas Generation from K East Basin Sludges - Series I Testing

Description: This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor and canister sludge. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge. The overall goals for this testing were to collect detailed gas generation rate and composition data to ascertain the quantity and reactivity of the metallic uranium (and other reactive species) present in the K Basin sludge. The gas generation evaluation included four large-scale vessels (850 ml) and eight small-scale vessels (30 ml) in an all-metal, leak tight system. The tests were conducted for several thousand hours at ambient and elevated temperatures (32 C, 40 C, 60 C, 80 C, and 95 C) to accelerated the reactions and provide conclusive gas generation data within a reasonable testing period. The sludge used for these tests was collected from the KE Basin floor and canister barrels (containing damaged spent fuel elements) using a consolidated sampling technique (i.e., material from several locations was combined to form ''consolidated samples''). Portions of these samples were sieved to separate particles greater than 250 m (P250) from particle less than 250 m (M250). This separation was performed to mimic the separation operations that are planned during the retrieval of certain K Basin sludge types and to gain a better understanding of how uranium metal is distributed in the sludge. The corrosion rate of the uranium metal particles in the sludge was found to agree reasonably well with corrosion rates reported in the literature.
Date: September 12, 2000
Creator: Delegard, Calvin H.; Bryan, Samuel A.; Schmidt, Andrew J.; Bredt, Paul R.; King, Christopher M.; Sell, Rachel L. et al.
Partner: UNT Libraries Government Documents Department
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Microrelay

Description: Our goals in this project were to (1) develop a new design concept for a high reliability microrelay, (2) build a prototype, and (3) demonstrate high force relay closure in the prototype. During FY1999, we designed a microrelay to meet commercial specifications: 3 g (or 0.03 N) closure force and 30-mA actuation current at less than 0.5 V. Our microrelay not only occupies less than 1 mm{sup 3}--about 1% of the volume of the smallest commercial part--but also its fabrication takes advantage of semiconductor processing, which has the potential to automate microrelay production. Conventional relays are fabricated by assembling many discrete parts. The process includes a number of nonautomated assembly and inspection steps, which increase fabrication cost and limit possible size reductions. Microrelays based on electrostatic forces can be fabricated by thin-film techniques employed in the semiconductor industry; however, the voltages required to make reliable electrical contact in an electrostatic relay significantly increase the cost of the driver. Microrelays based on electromagnetic forces, on the other hand, provide reliable contacts at low voltage. Reliable metal-to-metal contacts require sufficient contact force to plastically deform contact surfaces at asperities-thereby increasing the contact area. On the other hand, contact metallurgy and the gaseous environment must be controlled to prevent contact welding, contamination, oxidation, and other effects that change contact resistance over time. A contact force of 3 g is commonly used with gold/gold-alloy contacts in a sealed relay (e.g., a reed relay). In this way, more than 10 million closures can be achieved with a resistance of less than 100 m{Omega}. Our prototype relay preserves the contact metallurgy of commercial relays. The fundamental innovation in the fabrication of our microrelay is the use of a 3-D lithographic process to create a ''winding'' around a discrete magnetic core. To achieve sufficient inductance to generate …
Date: September 8, 2000
Creator: Bernhardt, A; Cooper, G & Malba, V
Partner: UNT Libraries Government Documents Department
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High Resolution Imaging of Vadose Zone Transport using Crosswell Radar and Seismic Methods

Description: Although borehole and outcrops provide some sampling there is a critical need to provide volumetric information between point measurements. For example, there is a need for information on heterogeneities at scales ranging from the centimeter to 10?s of meters, as these features can alter contaminant transport significantly. At Hanford, heterogeneities of interest can range from localized phenomena such as silt or gravel lenses, fractures, clastic dikes, to large-scale lithologic discontinuities. These features have been suspected of leading to funneling and fingering, additional physical mechanisms that could alter and possibly accelerate the transport of contaminants to underlying groundwater. It has also been observed from the studies to date that over relatively short distances there are heterogeneities in the physical structure of the porous medium and structural differences between repacked soil cores and the field site from which the materials initially came. Crosswell geophysical measurements are one means to provide this information.
Date: September 1, 2000
Creator: Majer, Ernest L.; Peterson, John E.; Williams, Kenneth H.; Daley, Thomas M. & Gee, Glendon W.
Partner: UNT Libraries Government Documents Department
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The 235U(n,2n(gamma)) Yrast Partial Gamma-Ray Cross Sections: A Report on the 1998 -- 1999 GEANIE Data and Analysis Techniques

Description: Measurements of partial {sup 235}U(n,2n{gamma}) {gamma}-ray cross sections have been carried out as a function of incident neutron energy using the GEANIE spectrometer at LANSCE/WNR. The yields of {gamma} rays resulting from the population of discrete levels in the residual nucleus {sup 234}U have been measured at incident neutron energies in the 1-20-MeV range. These data provide, with the aid of nuclear reaction modeling, a measurement of the {sup 235}U(n,2n) reaction cross section and serve as a proof of principle of the y-ray technique for the parallel 23gPu(n,2n) measurement [l]. This paper presents the analysis of the {gamma}-ray data and the extraction of partial {gamma}-ray cross sections as a function of incident neutron energy. Uncertainties associated with the spectroscopic analysis of the data and validation of the results are discussed in detail.
Date: September 1, 2000
Creator: Younes, W.; Becker, J. A.; Bernstein, L. A.; Garret, P. E.; McGrath, C. A.; McNabb, D. P. et al.
Partner: UNT Libraries Government Documents Department
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Environmental Report 1999

Description: Lawrence Livermore National Laboratory (LLNL), a U.S. Department of Energy (DOE) facility operated by the University of California (UC), serves as a national resource of scientific, technical, and engineering capabilities. The Laboratory's mission focuses on nuclear weapons and national security, and over the years has been broadened to include areas such as strategic defense, energy, the environment, biomedicine, technology transfer, the economy, and education. The Laboratory carries out this mission in compliance with local, state, and federal environmental regulatory requirements. It does so with the support of the Environmental Protection Department, which is responsible for environmental monitoring and analysis, hazardous waste management, environmental restoration, and assisting Laboratory organizations in ensuring compliance with environmental laws and regulations. LLNL comprises two sites: the Livermore site and Site 300. The Livermore site occupies an area of 3.28 square kilometers on the eastern edge of Livermore, California. Site 300, LLNL's experimental testing site, is located 24 kilometers to the east in the Altamont Hills and occupies an area of 30.3 square kilometers. Meteorological and environmental monitoring activities are conducted at both sites as well as in surrounding areas. This summary provides an overview of LLNL's environmental activities in 1999, including radiological and nonradiological surveillance, effluent and compliance monitoring, remediation, assessment of radiological releases and doses, and determination of the impact of LLNL operations on the environment and public health.
Date: September 1, 2000
Creator: Larson, J. M.; Biermann, A. H.; Harrach, R. J.; Althouse, P. E.; Bertoldo, N. A.; Blake, R. G. et al.
Partner: UNT Libraries Government Documents Department
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Electric Demand Reduction for the U.S. Navy Public Works Center San Diego, California

Description: Pacific Northwest National Laboratory investigated the profitability of operating a Navy ship's generators (in San Diego) during high electricity price periods rather than the ships hooking up to the Base electrical system for power. Profitability is predicated on the trade-off between the operating and maintenance cost incurred by the Navy for operating the ship generators and the net profit associated with the sale of the electric power on the spot market. In addition, PNNL assessed the use of the ship's generators as a means to achieve predicted load curtailments, which can then be marketed to the California Independent System Operator.
Date: September 30, 2000
Creator: Kintner-Meyer, Michael CW
Partner: UNT Libraries Government Documents Department
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Hanford Site Environmental Report for Calendar Year 1999

Description: The Hanford Site environmental report is prepared annually to summarize environmental data and information, to describe environmental management performance, to demonstrate the status of compliance with environmental regulations, and to highlight major environmental programs and efforts.
Date: September 28, 2000
Creator: Poston, Ted M.; Hanf, Robert W. & Dirkes, Roger L.
Partner: UNT Libraries Government Documents Department
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Development of object-oriented tools for the numerical solution of reactive flow

Description: The primary work carried out under the subcontract involved the development of object-oriented application software, within the Overture framework of codes, for the numerical simulation of high speed reactive flow. The mathematical model on which the software is based is the reactive Euler equations. The implementation of this model is fairly general and allows for multiple reacting species and reaction rates and a general equation of state with the aim of being able to simulate experimentally observed phenomena in gas or solid explosives. The software is part of the OverBlown package of fluids codes, developed and maintained by Bill Henshaw and the Overture team at CASC. It uses overlapping grids in order to handle general domains and the A++/P++ array class library (developed by Dan Quinlan and the Overture team) which allows parallel processing. An implementation of a patch grid-type adaptive mesh refinement (AMR) scheme for the code was initiated, but not completed under the current subcontract. The software has been carefully tested for accuracy using existing codes written previously by the author, and it has been used to compute the evolution to detonation of reactive samples subject to various initial conditions and within various confinement geometries. Work on a number of smaller projects has also taken place. These include methods for conservative interpolation on general curvilinear grids, methods for characteristic interpolation, and developing software tools for numerical quadrature on overlapping grids.
Date: September 30, 2000
Creator: Schwendeman, D W
Partner: UNT Libraries Government Documents Department
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