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The Geochemical Earth Reference Model (GERM)

Description: The Geochemical Earth Reference Model (GERM) initiative is a grass- roots effort with the goal of establishing a community consensus on a chemical characterization of the Earth, its major reservoirs, and the fluxes between them. Long term goal of GERM is a chemical reservoir characterization analogous to the geophysical effort of the Preliminary Reference Earth Model (PREM). Chemical fluxes between reservoirs are included into GERM to illuminate the long-term chemical evolution of the Earth and to characterize the Earth as a dynamic chemical system. In turn, these fluxes control geological processes and influence hydrosphere-atmosphere-climate dynamics. While these long-term goals are clearly the focus of GERM, the process of establishing GERM itself is just as important as its ultimate goal. The GERM initiative is developed in an open community discussion on the World Wide Web (GERM home page is at http://www-ep.es.llnl. gov/germ/germ-home.html) that is mediated by a series of editors with responsibilities for distinct reservoirs and fluxes. Beginning with the original workshop in Lyons (March 1996) GERM is continued to be developed on the Internet, punctuated by workshops and special sessions at professional meetings. It is planned to complete the first model by mid-1997, followed by a call for papers for a February 1998 GERM conference in La Jolla, California.
Date: December 1, 1996
Creator: Staudigel, H.; Albarede, F.; Shaw, H.; McDonough, B. & White, W.
Partner: UNT Libraries Government Documents Department

Fabrication and testing of a high field dipole mechanical model

Description: As a first step towards the development of a high field Nb{sub 3}Sn superconducting dipole for a Very Large Hadron Collider (VLHC), a short mechanical model was built and tested at Fermilab. The aim of this work was to develop simpler fabrication techniques and test new structural materials to use in the dipole model. The coil design was based on a two-layer cos({theta}) approach. The end parts were designed using ROXIE magnet optimization program and manufactured using a 6-axis EDM machine. The two layers of each half-coil were wound using one piece of cable without any interlayer splices. After winding, a ceramic matrix was applied to the each half-coil and the coil was cured under compression at 150 C. The two half-coils were then assembled together in a reaction fixture for heat treatment at 450 C for 8 hours. After reaction, the coils were placed in a curing fixture for epoxy impregnation. Finally some mechanical and electrical tests were performed after which the coils were sectioned to check the cable positioning and impregnation quality. This paper summarizes the results and experience obtained from the mechanical model.
Date: January 6, 2000
Creator: Yadav, S.
Partner: UNT Libraries Government Documents Department

Development of a SWIR solar spectral radiometer for the ARM program. Final report

Description: The goal of this grant was to develop an absolutely calibrated spectral radiometer covering the 1 to 5 {micro}m spectral region of the DOE ARM (Atmospheric Radiation Measurements) program. This instrument is called the Absolute Solar Transmittance Interferometer (ASTI). This effort was based on earlier results from grant DE-FG02-92ER61360. The instrument is based on a small, commercially available interferometer, built by Bomem, Inc., of Quebec, Canada. For the earlier grant, the authors constructed a breadboard version of ASTI, which was used to study the linearity, zero offset, gain stability, etc. These all indicated that an instrument of this type could achieve precision of 1% or better, with accuracy limited by the calibration standards (nominally 3%). For this grant they constructed a prototype instrument for possible use at the ARM sites.
Date: September 1, 1998
Creator: Murcray, F.
Partner: UNT Libraries Government Documents Department

Measurements and models for hazardous chemical and mixed wastes. 1998 annual progress report

Description: 'Aqueous waste of various chemical compositions constitutes a significant fraction of the total waste produced by industry in the US. A large quantity of the waste generated by the US chemical process industry is waste water. In addition, the majority of the waste inventory at DoE sites previously used for nuclear weapons production is aqueous waste. Large quantities of additional aqueous waste are expected to be generated during the clean-up of those sites. In order to effectively treat, safely handle, and properly dispose of these wastes, accurate and comprehensive knowledge of basic thermophysical property information is paramount. This knowledge will lead to huge savings by aiding in the design and optimization of treatment and disposal processes. The main objectives of this project are: Develop and validate models that accurately predict the phase equilibria and thermodynamic properties of hazardous aqueous systems necessary for the safe handling and successful design of separation and treatment processes for hazardous chemical and mixed wastes. Accurately measure the phase equilibria and thermodynamic properties of a representative system (water + acetone + isopropyl alcohol + sodium nitrate) over the applicable ranges of temperature, pressure, and composition to provide the pure component, binary, ternary, and quaternary experimental data required for model development. As of May, 1998, nine months into the first year of a three year project, the authors have made significant progress in the database development, have begun testing the models, and have been performance testing the apparatus on the pure components.'
Date: June 1, 1998
Creator: Holcomb, C.; Watts, L.; Outcalt, S.L.; Louie, B.; Mullins, M.E. & Rogers, T.N.
Partner: UNT Libraries Government Documents Department

Performance results for Beamlet: A large aperture multipass Nd glass laser

Description: The Beamlet laser is a large aperture, flashlamp pumped Nd: glass laser that is a scientific prototype of an advanced Inertial Fusion laser. Beamlet has achieved third harmonic, conversion efficiency of near 80% with its nominal 35cm {times} 35cm square beam at mean 3{omega} fluences in excess of 8 J/cm{sup 2}(3-ns). Beamlet uses an adaptive optics system to correct for aberrations and achieve less than 2 {times} diffraction limited far field spot size.
Date: April 11, 1995
Creator: Campbell, J.H.; Barker, C.E.; VanWonterghem, B.M.; Speck, D.R.; Behrendt, W.C.; Murray, J.R. et al.
Partner: UNT Libraries Government Documents Department

Flow visualization of forced and natural convection in internal cavities. 1998 annual progress report

Description: 'The objective of this research program is to understand the fluid physics when corroded spent nuclear fuel (SNF) elements are passivated by injecting treatment gases into a storage canister. By developing a reliable predictive technique for the energy, mass, and momentum transfer in the presence of surface reactions, transfer and storage systems can be efficiently and safely designed. The objective will be reached by using innovative flow visualization techniques and experimental measurements of the flow field to support computational models. This report summarizes work completed after eight months of a three-year, collaborative project. A generic idealization of a combined drying and passivation approach has been defined, which represents a section of a vertical canister with baskets of SNF elements. This simulation includes flow phenomena that occur in canisters for high- and/or low-enrichment fuels. A steady flow of the passivation fluid is introduced at the bottom of the canister via a central tube from the top. Fluid flows through an array of holes in the perforated basket support plate then around the simulated elements and out the top. Dimensions and flow rates for the idealized situation correspond to those for typical drying canisters. Approximate calculations have identified the ranges of values of flow parameters needed to determine the flow regimes occurring in practice.'
Date: June 1, 1998
Creator: Crepeau, J.C.; McEligot, D.M.; Clarksean, R.; Guezennec, Y.G. & Brodkey, R.S.
Partner: UNT Libraries Government Documents Department

Design of a relativistic klystron two-beam accelerator prototype

Description: We are designing an experiment to study physics, engineering, and costing issues of an extended Relativistic Klystron Two-Beam Accelerator (RK-TBA). The experiment is a prototype for an RK-TBA based microwave power source suitable for driving a 1 TeV linear collider. Major components of the experiment include a 2.5-MV, 1.5-kA electron source, a 11.4-GHz modulator, a bunch compressor, and a 8-m extraction section. The extraction section will be comprised of 4 traveling-wave output structures, each generating about 360 MW of rf power. Induction cells will be used in the extraction section to maintain the average beam energy at 5 MeV. Status of the design is presented.
Date: October 1, 1995
Creator: Westenskow, G.; Caporaso, G. & Chen, Y.
Partner: UNT Libraries Government Documents Department

Ribbon and gliding type parachutes evaluated in the 7 by 10 foot transonic wind tunnel

Description: An experiment has been conducted in the NSRDC 7- x 10-foot transonic tunnel for the Sandia Corporation to evaluate various parachute parameters. The experiment consisted of three main parts: the first phase evaluated the disreefing characteristics of the various parachutes as well as the drag forces before, during, and after disreefing; the second phase measured the pressure distribution around the chute as well as the drag forces; and the final phase evaluated the disreefing and drag characteristics of gliding type parachutes. The free stream dynamic pressure varied from 65 to 500 psf. 12 figures, 1 table. (auth)
Date: September 1, 1975
Creator: Ottensoser, J.
Partner: UNT Libraries Government Documents Department

A Compact, Low-Power Cantilever-Based Sensor Array for Chemical Detection

Description: A compact and low-power cantilever-based sensor array has been developed and used to detect various vapor analytes. This device employs sorptive polymers that are deposited onto piezoresistive cantilevers. We have successfully detected several organic vapors, representing a breadth of chemical properties and over a range of concentrations. Comparisons of the polymer/vapor partition coefficient to the cantilever deflection responses show that a simple linear relationship does not exist, emphasizing the need to develop an appropriate functional model to describe the chemical-to-mechanical transduction that is unique to this sensing modality.
Date: February 22, 2007
Creator: Loui, A; Ratto, T; Wilson, T; Mukerjee, E; Hu, Z; Sulchek, T et al.
Partner: UNT Libraries Government Documents Department

Integration of rapid prototyping into design and manufacturing

Description: The introduction of rapid prototyping machines into the marketplace promises to revolutionize the process of producing prototype parts with production-like quality. In the age of concurrent engineering and agile manufacturing, it is necessary to exploit applicable new technologies as soon as they become available. The driving force behind integrating these evolutionary processes into the design and manufacture of prototype parts is the need to reduce lead times and fabrication costs, improve efficiency, and increase flexibility without sacrificing quality. Sandia utilizes Stereolithography (SL) and Selective Laser Sintering (SLS) capabilities to support internal design and manufacturing efforts. SL is used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit-check models, visual aids for manufacturing, and functional parts in assemblies. SLS is used to produce wax patterns for the lost wax process of investment casting in support of an internal Sandia National Laboratories program called FASTCAST which integrates experimental and computational technologies into the investment casting process. This presentation will provide a brief overview of the SL and SLS processes and address our experiences with these technologies from the standpoints of application, accuracy, surface finish, and feature definition. Also presented will be several examples of prototype parts manufactured by the Stereolithography and Selective Laser Sintering rapid prototyping machines.
Date: October 1, 1993
Creator: Atwood, C. L.; McCarty, G. D.; Pardo, B. T. & Bryce, E. A.
Partner: UNT Libraries Government Documents Department

Integration of rapid prototyping into design and manufacturing

Description: The introduction of rapid prototyping machines into the market place promises to revolutionize the process of producing prototype parts with production-like quality. In the age of concurrent engineering and agile manufacturing, it is necessary to exploit applicable new technologies as soon as they become available. The driving force behind integrating these evolutionary processes into the design and manufacture of prototype parts is the need to reduce lead times and fabrication costs improve efficiency, and increase flexibility without sacrificing quality. Sandia Utilizes stereolithography and selective laser sintering capabilities to support internal design and manufacturing efforts. Stereolithography (SLA) is used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit check models, visual aids for manufacturing, and functional parts in assemblies. Selective laser sintering (SLS) is used to produce wax patterns for the lost wax process of investment casting in support of an internal Sandia National Laboratories program called FASTCAST which integrates experimental and computational technologies into the investment casting process. This presentation will provide a brief overview of the SLA and SLS processes and address our experiences with these technologies from the standpoints of application, accuracy, surface finish, and feature definition. Also presented will be several examples of prototype parts manufactured by the stereolithography and selective laser sintering rapid prototyping machines.
Date: April 1, 1993
Creator: Atwood, C. L.; McCarty, G. D. & Pardo, B. T.
Partner: UNT Libraries Government Documents Department

Integration of rapid prototyping into product development

Description: Sandia National Laboratories is a vertically multi-disciplined research and development laboratory with a long history of designing and developing d electro-mechanical products in the national interest. Integrating new technologies into the prototyping phase of our development cycle is necessary to reduce the cycle time from initial design to finished product. The introduction of rapid prototyping machines into the marketplace promises to revolutionize the process of producing prototype parts with relative speed and production-like quality. Issues of accuracy, feature definition, and surface finish continue to drive research and development of these processes. Sandia uses Stereolithography (SL) and Selective Laser Sintering (SLS) capabilities to support internal product development efforts. The primary use of SL and SLS is to produce patterns for investment casting in support of a Sandia managed program called FASTCAST that integrates computational technologies and experimental data into the investment casting process. These processes are also used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit-check models, visual aids for manufacturing, and functional parts in assemblies. This presentation will provide an overview of the SL and SLS processes and an update of our experience and success in integrating these technologies into the product development cycle. Also presented will be several examples of prototype parts manufactured using SL and SLS with a focus on application, accuracy, surface and feature definition.
Date: December 31, 1993
Creator: Atwood, C. L.; McCarty, G. D.; Pardo, B. T. & Bryce, E. A.
Partner: UNT Libraries Government Documents Department

Design and Performance of a 2-Megawatt High Voltage DC Test Load

Description: A high-power water-cooled resistive load which simulates the electrical load characteristics of a high-power klystron, capable of a 2 MW dissipation at 95 kV DC, is designed and installed. The load utilizes wirewound resistor elements suspended inside G-11 insulated tubing contained within a single-wall 316 stainless steel pressure vessel with flanged elliptical heads. The vessel supplies a continuous flow of deionized water. Baffles fabricated from G-10 sheets support the tubing and promote water turbulence to maximize heat removal. A companion oil tank houses resistive filament and mod-anode power supply test loads, plus an electrical interlock system which provides protection from inadequate water flow, excessive oil temperature, and arcing in either the pressure vessel or oil tank. A secondary safety system consists of both hydrostatic and steam pressure relief valves on the pressure vessel. Power supply tests indicate the load simulates the electrical load characteristics of a high-power klystron to a degree sufficient to accurately performance-test the rf high voltage power supplies used at the Advanced Photon Source.
Date: July 1, 1994
Creator: Horan, D.; Kustom, R. & Ferguson, M.
Partner: UNT Libraries Government Documents Department

Steam foam studies in the presence of residual oil

Description: The lack of understanding regarding foam flow in porous media necessitates further research. This paper reports on going work at Stanford University aimed at increasing our understanding in the particular area of steam foams. The behavior of steam foam is investigated with a one dimensional (6 ft. {times} 2.15 in.) sandpack under residual oil conditions of approximately 12 percent. The strength of the in-situ generated foam, indicated by pressure drops, is significantly affected by injection procedure, slug size, and steam quality. The surfactant concentration effect is minor in the range studied. In the presence of residual oil the simultaneous injection of steam and surfactant fails to generate foam in the model even though the same procedure generates a strong foam in the absence of oil. Nevertheless when surfactant is injected as a slug ahead of the steam using a surfactant alternating (SAG) procedure, foam is generated. The suggested reason for the success of SAG is the increased phase mixing that results from steam continually having to reestablish a path through a slug of surfactant solution.
Date: May 1, 1992
Creator: Hutchinson, D. A.; Demiral, B. & Castanier, L. M.
Partner: UNT Libraries Government Documents Department

Design verification and cold-flow modeling test report

Description: This report presents a compilation of the following three test reports prepared by TRW for Alaska Industrial Development and Export Authority (AIDEA) as part of the Healy Clean Coal Project, Phase 1 Design of the TRW Combustor and Auxiliary Systems, which is co-sponsored by the Department of Energy under the Clean Coal Technology 3 Program: (1) Design Verification Test Report, dated April 1993, (2) Combustor Cold Flow Model Report, dated August 28, 1992, (3) Coal Feed System Cold Flow Model Report, October 28, 1992. In this compilation, these three reports are included in one volume consisting of three parts, and TRW proprietary information has been excluded.
Date: July 1, 1993
Partner: UNT Libraries Government Documents Department

Soil structural analysis tools and properties for Hanford site waste tank evaluation

Description: As Hanford Site contractors address future structural demands on nuclear waste tanks, built as early as 1943, it is necessary to address their current safety margins and ensure safe margins are maintained. Although the current civil engineering practice guidelines for soil modeling are suitable as preliminary design tools, future demands potentially result in loads and modifications to the tanks that are outside the original design basis and current code based structural capabilities. For example, waste removal may include cutting a large hole in a tank. This report addresses both spring modeling of site soils and finite-element modeling of soils. Additionally seismic dynamic modeling of Hanford Site soils is also included. Of new and special interest is Section 2.2 that Professor Robert D. Holtz of the University of Washington wrote on plane strain soil testing versus triaxial testing with Hanford Site application to large buried waste tanks.
Date: September 1, 1995
Creator: Moore, C.J.; Holtz, R.D.; Wagenblast, G.R.; Weiner, E.D. & Marlow, R.S.
Partner: UNT Libraries Government Documents Department

Effect of longer combination vehicles on the total logistic costs of truckload shippers

Description: The purpose of the research described in this paper was to examine the effects of using longer and heavier tractor-trailer combinations from the standpoint of the individual firm or shipper rather than from the viewpoint of the motor carrier. The objective was to determine the effect of longer combination vehicles (LCVS) not only on shippers freight costs but on their inventory and other logistical costs as well. A sample of companies in selected industries provided data on their principal products, traffic flows, and logistics costs in a mail survey. These data were entered into a computer program called the Freight Transportation Analyzer (FTA) which calculated the component logistics costs associated with shipping by single trailers and by two alternative types of double trailer LCVS. A major finding of the study was that, given sufficient flows of a company`s product in a traffic lane, LCVs would in most cases greatly reduce the total logistics cost of firms that currently ship in single trailer truckload quantities. Annual lane volume, lane distance, and annual lane ton-mileage appeared to be good indicators of whether or not shipping by LCVs would benefit a company, whereas product value had surprisingly little influence on the cost-effectiveness of LCVS. An even better indicator was the ratio of current annual freight costs to current annual inventory carrying costs for a firm`s single trailer truckload shipments. Given the current trend toward maintaining small inventories and shipping in small quantities, it is not clear to what extent shippers will abandon single trailer transport to take advantage of the potential reduction in total logistics cost afforded by LCVS.
Date: October 12, 1994
Creator: Middendorf, D.P.; Bronzini, M.S.; Jacoby, J. & Coyle, J.J.
Partner: UNT Libraries Government Documents Department

2x1 prototype plasma-electrode pockels cell (PEPC) for the National Ignition Facility

Description: A large aperture optical switch based on plasma electrode Pockels cell (PEPC) technology is an integral part of the National Ignition Facility (NIP) laser design. This optical switch will trap the input optical pulse in the NIF amplifier cavity for four gain passes and then switch the high-energy output optical pulse out of the cavity. The switch will consist of arrays of plasma electrode Pockels cells working in conjunction with thin-film, Brewster`s angle polarizes. The 192 beams in the NIF will be arranged in 4x2 bundles. To meet the required beam-to-beam spacing within each bundle, we have proposed a NIF PEPC design based on a 4x1 mechanical module (column) which is in turn comprised of two electrically independent 2x1 PEPC units. In this paper, we report on the design a single 2x1 prototype module and experimental tests of important design issues using our single, 32 cm aperture PEPC prototype. The purpose the 2x1 prototype is to prove the viability of a 2x1 PEPC and to act, as an engineering test bed for the NIF PEPC design.
Date: October 1, 1996
Creator: Rhodes, M. A.
Partner: UNT Libraries Government Documents Department

Scaling issues in dynamic fragmentation

Description: A set of relations which would allow the experimental results of impact fragmentation experiments conducted under the controlled environment of a testing laboratory to be confidently scaled to realistic system dimensions would be an effective tool in the developments toward a predictive capability in full scale applications involving fragmentation. Here some of the issues governing scaling relations in dynamic fragmentation are discussed. Dimensional arguments are pursued. Some of the consequences indicate that fragmentation scaling relations are dependent on the specific material properties and mechanisms governing the fragmentation process. Transitions in functional forms of the scaling relations can be expected under conditions in which fragmentation mechanism transitions occur in complex engineering materials. Some computational simulations and experimental impact fragmentation results are examined.
Date: March 1995
Creator: Grady, D.
Partner: UNT Libraries Government Documents Department

Guide for developing conceptual models for ecological risk assessments

Description: Ecological conceptual models are the result of the problem formulation phase of an ecological risk assessment, which is an important component of the Remedial Investigation process. They present hypotheses of how the site contaminants might affect the site ecology. The contaminant sources, routes, media, routes, and endpoint receptors are presented in the form of a flow chart. This guide is for preparing the conceptual models; use of this guide will standardize the models so that they will be of high quality, useful to the assessment process, and sufficiently consistent so that connections between sources of exposure and receptors can be extended across operable units (OU). Generic conceptual models are presented for source, aquatic integrator, groundwater integrator, and terrestrial OUs.
Date: May 1, 1996
Creator: Suter, G.W., II
Partner: UNT Libraries Government Documents Department

Transportable X-ray cart

Description: The main body of the report summarizes the project scope, project milestones, highlights any unresolved problems encountered during the project and includes a summary of the financial information. The purpose of this CRADA was to assist Digiray Corporation in the development and evaluation of a Transportable Reverse Geometry X-Ray 0 (RGX-T) cart for aircraft inspection Scope: LLNL was to provide a review of the RGX-T engineering drawing package supplied by Digiray, suggest and incorporate design modifications, fabricate, assemble and provide performance evaluation testing of the RGX-T prototype. Major deliverables were (a) engineering design analysis and evaluation (b) cart prototype hardware, and (c) performance evaluation. Schedule: Procurement and technical delays extended the project twelve months past than the original four month project duration estimate. LLNL reviewed engineering drawings of the RGX-T prototype provided by Digiray, performed a engineering design analysis and evaluation, suggested and incorporated modifications to improve design safety factors, fabricated and assembled the prototype system, and evaluated the motion and positioning capabilities of the assembled system. The RGX-T provides a limited set of positioning orientations for the Digiray x-ray tube head that do not meet the overall Digiray requirements for aircraft inspection. In addition, mechanical stability concerns remain for positioning the tube head with the mechanical arm and for rolling the assembly with arbitrary orientation of the mechanical arm.
Date: December 1, 1995
Partner: UNT Libraries Government Documents Department

AOCM program 1992 to 1993 status report: Basilisk subscale laser experiments

Description: This report summarizes the work performed by the Advanced Optical Counter Measures (AOCM) program from January 1992 to February 1993, funded by the US DOD and administered by the US Army`s Night Vision and Electro-optics Directorate (NVEOD). The AOCM program objective was the development of an advanced anti-sensor weapon system, the Basilisk laser. Basilisk is a high power, white light laser. Its compact size permits deployment on a variety of platforms, including the Bradley Fighting vehicle, where Basilisk would augment the Bradley`s conventional weapon systems. The effectiveness of Basilisk was recently demonstrated in a series of battlefield simulations, CTAS 2.5, where its Mission Defeat Score was eight times higher than lower energy anti-sensor laser systems. In November 1991, a five phase strategy was proposed to develop the Basilisk white light laser system. This report documents the experimental activities performed by the AOCM program and describes several major experimental milestones we achieved during the first year of funding. The focus of this report is on a series of subscale experiments to demonstrate key laser physics and engineering technologies.
Date: January 13, 1994
Creator: Hermann, M.; Norton, M.; Honig, J. & Hackel, L.
Partner: UNT Libraries Government Documents Department

Liaison based assembly design

Description: Liaison Based Assembly Design extends the current information infrastructure to support design in terms of kinematic relationships between parts, or liaisons. These liaisons capture information regarding contact, degrees-of-freedom constraints and containment relationships between parts in an assembly. The project involved defining a useful collection of liaison representations, investigating their properties, and providing for maximum use of the data in downstream applications. We tested our ideas by implementing a prototype system involving extensions to Pro/Engineer and the Archimedes assembly planner. With an expanded product model, the design system is more able to capture design intent. When a product update is attempted, increased knowledge availability improves our ability to understand the effect of design changes. Manufacturing and analysis disciplines benefit from having liaison information available, so less time is wasted arguing over incomplete design specifications and our enterprise can be more completely integrated.
Date: December 1, 1996
Creator: Ames, A.; Kholwadwala, D. & Wilson, R.H.
Partner: UNT Libraries Government Documents Department