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Alternative Fuel News, Vol. 2, No. 5

Description: In this issue of the Alternative Fuel News, the authors remember what happened just 25 years ago (the energy crisis of 1973) and reiterate that foreign oil dependence is still a national issue. Highlighted are some the successes in the Clean Cities Program and the alternative fuels industry. Also featured is the Natural Gas Vehicle Coalition (NGVC) and the United States Postal Service (USPS) delivers with AFVs.
Date: January 6, 1999
Creator: National Renewable Energy Laboratory (U.S.)
Partner: UNT Libraries Government Documents Department

BTS strategic plan executive summary

Description: This Strategic Plan positions the Office of Building Technology, State and Community Programs (BTS) to be more effective in reducing energy consumption in homes, offices, schools and other buildings, and in reducing environmental impacts associated with energy use.
Date: January 6, 1999
Partner: UNT Libraries Government Documents Department

Cryogenic moderator simulations : confronting reality.

Description: The Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory is a spallation neutron source dedicated to materials research. Its three cryogenic methane moderators provide twelve neutron beams to fourteen instruments and test facilities. This report concerns ongoing activities for benchmarking our Monte Carlo model of the IPNS neutron generation system. This paper concentrates on the techniques (both experimental and calculational) used in such benchmarking activities.
Date: January 6, 1999
Creator: Iverson, E. B.
Partner: UNT Libraries Government Documents Department

ESR Process Instabilities while Melting Pipe Electrodes

Description: With the demonstration of the viability of using the electroslag remelting process for the decontamination of radionuclides, interest has increased in examining the unique aspects associated with melting steel pipe electrodes. These electrodes consist of several nested pipes, welded concentrically to atop plate. Since these electrodes can be half as dense as a solid electrode, they present unique challenges to the standard algorithms used in controlling the melting process. Naturally the electrode must be driven down at a dramatically increased speed. However, since the heat transfer is greatly influenced and enhanced with the increased area to volume ratio, considerable variation in the melting rate of the pipes has been found. Standard control methods can become unstable as a result of the variation at increased speeds, particularly at shallow immersion depths. The key to good control lies in the understanding of the melting process. Several experiments were conducted to observe the characteristics of the melting using two different control modes. By using a pressure transducer to monitor the pressure inside the pipes, the venting of the air trapped inside the electrode was observed. The measurements reveal that for a considerable amount of time. the pipes are not completely immersed in the slag, allowing the gas inside to escape without the formation of bubbles. This result has implications for the voltage swing as well as for the decontamination reactions.
Date: January 6, 1999
Creator: Melgaard, D.K. & Shelmidine, G.J.
Partner: UNT Libraries Government Documents Department

Implicit solution of large-scale radiation - material energy transfer problems

Description: Modeling of radiation-diffusion processes has traditionally been accomplished through simulations based on decoupling and linearizing the basic physics equations. By applying these techniques, physicists have simplified their model enough that problems of moderate sizes could be solved. However, new applications demand the simulation of larger problems for which the inaccuracies and nonscalability of current algorithms prevent solution. Recent work in iterative methods has provided computational scientists with new tools for solving these problems. In this paper, we present an algorithm for the implicit solution of the multi- group diffusion approximation coupled to an electron temperature equation. This algorithm uses a stiff ODE solver coupled with Newton's method for solving the implicit equations arising at each time step. The Jacobian systems are solved by applying GMRES preconditioned with a semicoarsening multigrid algorithm. By combining the nonlinear Newton iteration with a multigrid preconditioner, we take advantage of the fast, robust nonlinear convergence of Newton's method and the scalability of the linear multigrid method. Numerical results show that the method is accurate and scalable.
Date: January 6, 1999
Creator: Brown, P. N.; Chang, B.; Graziani, F. & Woodward, C. S.
Partner: UNT Libraries Government Documents Department

The International Criminal Court Treaty: Description, Policy Issues, and Congressional Concerns

Description: This report discusses the events leading to the creation of a permanent international criminal tribunal and U.S. perspectives on the Court including: problematic provisions in the ICC Treaty, congressional considerations, and potential implications for U.S. foreign policy.
Date: January 6, 1999
Creator: Grigorian, Ellen
Partner: UNT Libraries Government Documents Department

Metal-Hydrogen Phase Diagrams in the Vicinity of Melting Temperatures

Description: Hydrogen-metal interaction phenomena belong to the most exciting challenges of today's physical metallurgy and physics of solids due to the uncommon behavior of hydrogen in condensed media and to the need for understanding hydrogen's strong negative impact on properties of some high-strength steels and.alloys. The paper cites and summarizes research data on fundamental thermodynamic characteristics of hydrogen in some metals that absorb it endothermally at elevated temperatures. For a number of metal-hydrogen systems, information on some phase diagrams previously not available to the English-speaking scientific community is presented.
Date: January 6, 1999
Creator: Shapovalov, V.I.
Partner: UNT Libraries Government Documents Department

Natural analogues of nuclear waste glass corrosion.

Description: This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information available on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses.
Date: January 6, 1999
Creator: Abrajano, T.A. Jr.; Ebert, W.L. & Luo, J.S.
Partner: UNT Libraries Government Documents Department

[News Clip: Fan Reax]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: January 6, 1999
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Numerical Modeling Tools for the Prediction of Solution Migration Applicable to Mining Site

Description: Mining has always had an important influence on cultures and traditions of communities around the globe and throughout history. Today, because mining legislation places heavy emphasis on environmental protection, there is great interest in having a comprehensive understanding of ancient mining and mining sites. Multi-disciplinary approaches (i.e., Pb isotopes as tracers) are being used to explore the distribution of metals in natural environments. Another successful approach is to model solution migration numerically. A proven method to simulate solution migration in natural rock salt has been applied to project through time for 10,000 years the system performance and solution concentrations surrounding a proposed nuclear waste repository. This capability is readily adaptable to simulate solution migration around mining.
Date: January 6, 1999
Creator: Martell, M. & Vaughn, P.
Partner: UNT Libraries Government Documents Department

Production of Gas-Solid Structures in Aluminum and Nickel Alloys by Gasar Processing

Description: Experimental data on directional and bulk solidification of hydrogen-charged samples of aluminum alloy A356 and nickel alloy Inconel 718 are discussed. The solidification structure of the porous zone is shown to be dependent on many process variables. Of these variables, hydrogen content in the melt prior to solidification, and furnace atmospheric pressure during solidification play the decisive role. Also important are the furnace atmosphere composition, the solidification velocity, and the temperature distribution of the liquid metal inside the mold.
Date: January 6, 1999
Creator: Apprill, J.M.; Baldwin, M.D.; Maguire, M.C.; Miszkiel, M.E. & Shapovalov, V.I.
Partner: UNT Libraries Government Documents Department

Report on the international workshop on cold moderators for pulsed neutron sources.

Description: The International Workshop on Cold Moderators for Pulsed Neutron Sources resulted from the coincidence of two forces. Our sponsors in the Materials Sciences Branch of DOE's Office of Energy Research and the community of moderator and neutron facility developers both realized that it was time. The Neutron Sources Working Group of the Megascience Forum of the Organization for Economic Cooperation and Development offered to contribute its support by publishing the proceedings, which with DOE and Argonne sponsorship cemented the initiative. The purposes of the workshop were: to recall and improve the theoretical groundwork of time-dependent neutron thermalization; to pose and examine the needs for and benefits of cold moderators for neutron scattering and other applications of pulsed neutron sources; to summarize experience with pulsed source, cold moderators, their performance, effectiveness, successes, problems and solutions, and the needs for operational data; to compile and evaluate new ideas for cold moderator materials and geometries; to review methods of measuring and characterizing pulsed source cold moderator performance; to appraise methods of calculating needed source characteristics and to evaluate the needs and prospects for improvements; to assess the state of knowledge of data needed for calculating the neutronic and engineering performance of cold moderators; and to outline the needs for facilities for testing various aspects of pulsed source cold moderator performance.
Date: January 6, 1999
Creator: Carpenter, J. M.
Partner: UNT Libraries Government Documents Department

Robots Working with Hazardous Materials

Description: While many research and development activities take place at Sandia National Laboratories' Intelligent Systems and Robotics Center (ISRC), where the "rubber meets the road" is in the ISRC'S delivered systems. The ISRC has delivered several systems over the last few years that handle hazardous materials on a daily basis, and allow human workers to move to a safer, supervisory role than the "hands-on" operations that they used to perform. The ISRC at Sandia performs a large range of research and development activities, including development and delivery of one-of-a-kind robotic systems for use with hazardous materials. Our mission is to create systems for operations where people can't or don't want to perform the operations by hand, and the systems described in this article are several of our first-of-a-kind deliveries to achieve that mission.
Date: January 6, 1999
Creator: Amai, W. & Fahrenholtz, J.
Partner: UNT Libraries Government Documents Department

Sandia National Laboratories Institutional Plan: FY 1999-2004

Description: This Institutional Plan is the most comprehensive yearly "snapshot" available of Sandia National Laboratories' major programs, facilities, human resources, and budget. The document also includes overviews of our missions, organization, capabilities, planning functions, milestones, and accomplishments. The document's purpose is to provide the above information to the US Department of Energy, key congressional committees, Sandia management, and other present and potential customers. Chapter 2 presents information about Sandia's mission and summarizes our recent revision of Sandia's Strategic Plan. Chapter 3 presents an overview of Sandia's strategic objectives, chapter 4 lists laboratory goals and milestones for FY 1999, and chapter 5 presents our accomplishments during FY 1998. Chapters 3 through 5 are organized around our eight strategic objectives. The four primary objectives cover nuclear weapons responsibilities, nonproliferation and materials control, energy and critical infrastructures, and emerging national security threats. The major programmatic initiatives are presented in chapter 7. However, the programmatic descriptions in chapter 6 and the Associated funding tables in chapter 9 continue to be presented by DOE Budget and Reporting Code, as in previous Sandia institutional plans. As an aid to the reader, the four primary strategic objectives in chapter 3 are cross-referenced to the program information in chapter 6.
Date: January 6, 1999
Creator: Garber, D.P.
Partner: UNT Libraries Government Documents Department

Securities and Exchange Commission: Regulation of Exchanges and Alternative Trading Systems

Description: Other written product issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO reviewed the Securities and Exchange Commission's (SEC) new rule on the regulation of exchanges and alternative trading systems (ATS). GAO noted that: (1) the rule would allow ATS to choose whether to register as national securities exchanges, or to register as broker-dealers, depending on their activities and trading volume; (2) in addition, Regulation ATS will require alternative trading systems that trade a certain volume of securities to make their best prices known to the public and allow non-subscribers access to those prices; (3) the final rule would also amend Rules 6a-1, 6a-2, and 6a-3 regarding registration as a national securities exchange; and (4) SEC complied with applicable requirements in promulgating the rule."
Date: January 6, 1999
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Spiraling Edge: Fast Surface Reconstruction from Partially Organized Sample Points

Description: Many applications produce three-dimensional points that must be further processed to generate a surface. Surface reconstruction algorithms that start with a set of unorganized points are extremely time-consuming. Often, however, points are generated such that there is additional information available to the reconstruction algorithm. We present a specialized algorithm for surface reconstruction that is three orders of magnitude faster than algorithms for the general case. In addition to sample point locations, our algorithm starts with normal information and knowledge of each point's neighbors. Our algorithm produces a localized approximation to the surface by creating a star-shaped triangulation between a point and a subset of its nearest neighbors. This surface patch is extended by locally triangulating each of the points along the edge of the patch. As each edge point is triangulated, it is removed from the edge and new edge points along the patch's edge are inserted in its place. The updated edge spirals out over the surface until the edge encounters a surface boundary and stops growing in that direction, or until the edge reduces to a small hole that fills itself in.
Date: January 6, 1999
Creator: Angel, E. & Crossno, P.
Partner: UNT Libraries Government Documents Department

A transport-based condensed history algorithm

Description: Condensed history algorithms are approximate electron transport Monte Carlo methods in which the cumulative effects of multiple collisions are modeled in a single step of (user-specified) path length s{sub 0}. This path length is the distance each Monte Carlo electron travels between collisions. Current condensed history techniques utilize a splitting routine over the range 0 {le} s {le} s{sub 0}. For example, the PEnELOPE method splits each step into two substeps; one with length {xi}s{sub 0} and one with length (1 {minus}{xi})s{sub 0}, where {xi} is a random number from 0 < {xi} < 1. because s{sub 0} is fixed (not sampled from an exponential distribution), conventional condensed history schemes are not transport processes. Here the authors describe a new condensed history algorithm that is a transport process. The method simulates a transport equation that approximates the exact Boltzmann equation. The new transport equation has a larger mean free path than, and preserves two angular moments of, the Boltzmann equation. Thus, the new process is solved more efficiently by Monte Carlo, and it conserves both particles and scattering power.
Date: January 6, 1999
Creator: Tolar Jr, D R
Partner: UNT Libraries Government Documents Department

Complex Systems: Science for the 21st Century

Description: Designed to help define new scientific directions related to complex systems in order to create new understanding about the nano world and complicated, multicomponent structures.
Date: March 6, 1999
Creator: Shank, C. V.; Awschalom, D.; Bawendi, M.; Fr├ęchet, J.; Murphy, D.; Stupp, S. et al.
Partner: UNT Libraries Government Documents Department