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Potential for use of all-MOX fuel in existing and evolutionary/advanced LWRs in the United States

Description: This paper reviews the application of US LWRs that are loaded with all-MOX fuel to dispose of excess weapon plutonium. The information presented is based on the DOE study results summarized in the 1993 DOE report, and the detailed reports submitted by reactor designers to DOE for that report. The reactor designs are the Westinghouse (Plutonium Disposition Reactor) PDR600, the GE Advanced BWR (ABWR), and ABB-Combustion Engineering System 80+. Analysis of published information in the nuclear community is the basis for an estimate of the capabilities of existing LWRs to switch from low-enriched uranium to all-MOX fuel. It is concluded to be feasible, if the conversion to PuO{sub 2} can be begun immediately, and lead test assemblies containing prototypical MOX fuel be made and irradiated. Russian VVERs should also be evaluated for Pu disposition.
Date: December 31, 1994
Creator: Walter, C.E.
Partner: UNT Libraries Government Documents Department

Symposium on the 30th anniversary of the ZGS startup: Proceedings

Description: These proceedings document a number of aspects of a big science facility and its impact on science, on technology, and on the continuing program of a major US research institution. The Zero Gradient Synchrotron (ZGS) was a 12.5 GeV weak focusing proton accelerator that operated at Argonne for fifteen years--from 1964 to 1979. It was a major user facility which led to new close links between the Laboratory and university groups: in the research program; in the choice of experiments to be carried out; in the design and construction of beams and detectors; and even in the Laboratory management. For Argonne, it marked a major move from being a Laboratory dominated by nuclear reactor development to one with a stronger basic research orientation. The present meeting covered the progress in accelerator science, in the applications of technology pioneered or developed by people working at the ZGS, as well as in physics research and detector construction. At this time, when the future of the US research programs in science is being questioned as a result of the ending of the Cold War and plans to balance the Federal budget, the specific place of the National Laboratories in the spectrum of research activities is under particular examination. This Symposium highlights one case history of a major science program that was completed more than a decade ago--so that the further developments of both the science and the technology can be seen in some perspective. The subsequent activities of the people who had worked in the ZGS program as well as the redeployment of the ZGS facilities were addressed. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date: December 31, 1994
Creator: Derrick, M.
Partner: UNT Libraries Government Documents Department

Project definition study for research facility access and science education

Description: This UTA/SMU project definition study describes critical customer services and research programs which draw upon SSC assets to meet regional needs in two major components: Science Education; Academic/Small Business R and D Facility Access. The location of the SSC in Texas constituted a significant stimulus to R and D activities in Texas, encouraging new initiatives in high energy physics, as well as stimulating other areas of physics and related sciences. An important aspect of maximizing the utility of the investment in the SSC should be to re-allocate SSC assets in ways that maintain that momentum. This study addresses several ways to achieve that end, extending benefits to all of physics, the sciences in general and particularly, to science education.
Date: October 1, 1994
Creator: Rosen, S.P. & Teplitz, V.L.
Partner: UNT Libraries Government Documents Department

The BNL EBIS Program: Status and plans

Description: Recently an Electron Beam Ion Source (EBIS), on long term loan from Sandia National Laboratories, has been put into operation at Brookhaven National Laboratory. This source is being primarily used as a test device to answer questions relevant to the eventual design of an EBIS-based heavy ion preinjector for RHIC; a secondary objective is to determine parameters of an EBIS capable of delivering fully stripped light ions up to neon for medical applications. Such a source can easily produce all ions in charge states as needed, but the challenge lies in reaching intensities of interest to RHIC (2--3 {times} 10{sup 9} particles/pulse). The source studies are planned to address issues such as scaling of the electron beam current in stages up to 10 A, possible onset and control of instabilities, external ion injection, parametric studies of the ion yield, charge state distributions and emittance of the extracted ion beam, ion cooling in the trap, and other technical and physics issues.
Date: December 1994
Creator: Beebe, E.; Alessi, J.; Hershcovitch, A.; Kponou, A.; Prelec, K. & Schmieder, R. W.
Partner: UNT Libraries Government Documents Department

Fifth international conference on hyperbolic problems -- theory, numerics, applications: Abstracts

Description: The conference demonstrated that hyperbolic problems and conservation laws play an important role in many areas including industrial applications and the studying of elasto-plastic materials. Among the various topics covered in the conference, the authors mention: the big bang theory, general relativity, critical phenomena, deformation and fracture of solids, shock wave interactions, numerical simulation in three dimensions, the level set method, multidimensional Riemann problem, application of the front tracking in petroleum reservoir simulations, global solution of the Navier-Stokes equations in high dimensions, recent progress in granular flow, and the study of elastic plastic materials. The authors believe that the new ideas, tools, methods, problems, theoretical results, numerical solutions and computational algorithms presented or discussed at the conference will benefit the participants in their current and future research.
Date: December 31, 1994
Partner: UNT Libraries Government Documents Department

Northeast regional biomass program. First quarter report, October--December 1993

Description: This progress report presents summaries of various projects which were in operation or being planned during this quarter period. Projects included testing the efficiency of using wood chips as fuel in heating systems, barriers to commercial development of wood pellet fuels, studies of more efficient and less polluting wood stoves, work on landfill gas utilization, directories of facilities using biomass fuels, surveys of biomass conversion processes to liquid fuels, for commercial development, etc.
Date: May 1, 1994
Partner: UNT Libraries Government Documents Department

The development and testing of ceramic components in piston engines. Final report

Description: Within the past 10--15 years, ceramic hardware has been fabricated and tested in a number of piston engine applications including valves, piston pins, roller followers, tappet shims, and other wear components. It has been shown that, with proper design and installation, ceramics improve performance, fuel economy, and wear and corrosion resistance. These results have been obtained using rig and road tests on both stock and race engines. Selected summaries of these tests are presented in this review paper.
Date: October 1, 1994
Creator: McEntire, B.J.; Willis, R.W. & Southam, R.E.
Partner: UNT Libraries Government Documents Department

Microfabricated microengine for use as a mechanical drive and power source in the microdomain and fabrication process

Description: A microengine uses two synchronized linear actuators as a power source and converts oscillatory motion from the actuators into rotational motion via direct linkage connection to an output gear or wheel. The microengine provides output in the form of a continuously rotating output gear that is capable of delivering drive torque to a micromechanism. The microengine can be operated at varying speeds and its motion can be reversed. Linear actuators are synchronized in order to provide linear oscillatory motion to the linkage means in the X and Y directions according to a desired position, rotational direction and speed of said mechanical output means. The output gear has gear teeth on its outer perimeter for directly contacting a micromechanism requiring mechanical power. The gear is retained by a retaining means which allows said gear to rotate freely. The microengine is microfabricated of polysilicon on one wafer using surface micromachining batch fabrication.
Date: December 31, 1994
Creator: Garcia, E.J. & Sniegowski, J.J.
Partner: UNT Libraries Government Documents Department

13. international conference on the application of accelerators in research and industry. Final performance technical report

Description: This report summarizes attendance at the conference, describes its session subjects and other activities, names its sponsoring organizations, and references where the papers published for it may be found (in Nuclear Instruments and Methods in Physics Research Vol. B 99 (1995)).
Date: December 31, 1994
Partner: UNT Libraries Government Documents Department

Research facility access & science education

Description: As Congress voted to terminate the Superconducting Super Collider (SSC) Laboratory in October of 1993, the Department of Energy was encouraged to maximize the benefits to the nation of approximately $2 billion which had already been expended to date on its evolution. Having been recruited to Texas from other intellectually challenging enclaves around the world, many regional scientists, especially physicists, of course, also began to look for viable ways to preserve some of the potentially short-lived gains made by Texas higher education in anticipation of {open_quotes}the SSC era.{close_quotes} In fact, by November, 1993, approximately 150 physicists and engineers from thirteen Texas universities and the SSC itself, had gathered on the SMU campus to discuss possible re-uses of the SSC assets. Participants at that meeting drew up a petition addressed to the state and federal governments requesting the creation of a joint Texas Facility for Science Education and Research. The idea was to create a facility, open to universities and industry alike, which would preserve the research and development infrastructure and continue the educational mission of the SSC.
Date: October 1, 1994
Creator: Rosen, S.P. & Teplitz, V.L.
Partner: UNT Libraries Government Documents Department

General particle transport equation. Final report

Description: The general objectives of this research are as follows: (1) To develop fundamental models for fluid particle coalescence and breakage rates for incorporation into statistically based (Population Balance Approach or Monte Carlo Approach) two-phase thermal hydraulics codes. (2) To develop fundamental models for flow structure transitions based on stability theory and fluid particle interaction rates. This report details the derivation of the mass, momentum and energy conservation equations for a distribution of spherical, chemically non-reacting fluid particles of variable size and velocity. To study the effects of fluid particle interactions on interfacial transfer and flow structure requires detailed particulate flow conservation equations. The equations are derived using a particle continuity equation analogous to Boltzmann`s transport equation. When coupled with the appropriate closure equations, the conservation equations can be used to model nonequilibrium, two-phase, dispersed, fluid flow behavior. Unlike the Eulerian volume and time averaged conservation equations, the statistically averaged conservation equations contain additional terms that take into account the change due to fluid particle interfacial acceleration and fluid particle dynamics. Two types of particle dynamics are considered; coalescence and breakage. Therefore, the rate of change due to particle dynamics will consider the gain and loss involved in these processes and implement phenomenological models for fluid particle breakage and coalescence.
Date: December 1, 1994
Creator: Lafi, A.Y. & Reyes, J.N. Jr.
Partner: UNT Libraries Government Documents Department

Bioremediation of wastewater containing RDX

Description: A free suspension model of the biodegradation of RDX by a consortium has been developed as a part of an overall model that will describe the waste treatment for explosives in a continuous process. The free suspension model uses experimentally determined parameters to predict the concentrations of the bacteria cells, the substrate (yeast extract), RDX, and the mononitroso intermediate. The model correctly predicts the experimentally observed trends; however, the values predicted for the cell concentrations are consistently lower than those observed experimentally. This can be resolved by better characterizing the growth parameters of the consortium. The degradation of RDX was found to be first order in RDX concentration and assumed to be first order in cell concentration, X. i.e. d(RDX)/dt = k{sub 1}(X)(RDX) The degradation rate constant, k{sub 1}, was found to be 0.043 L/(g cells hr). Similarly, the degradation rate constant of the mononitroso intermediate was found to be 0.066 L/(g cells hr).
Date: October 1, 1994
Creator: Ogden, K. L.
Partner: UNT Libraries Government Documents Department

Laser ablation of contaminants from concrete and metal surfaces. Topical report, June--December 1994

Description: Tests have demonstrated that it is possible to clean coatings off surfaces using high-power, pulsed, high-repetition-rate lasers. Purpose of this contract is to demonstrate (1) that pulsed-repetition lasers can be used to remove paint from concrete and metal surfaces, including cleaning out the surface pores, (2) that the cleaning process will result in negligible release of contaminated ablated material to the environment, and (3) that the process generates negligible additional waste compared to competing technologies. This report covers technical progress during Phase 1 of the contract and makes recommendations for technology development in Phase 2.
Date: December 1994
Creator: Freiwald, J. & Freiwald, D. A.
Partner: UNT Libraries Government Documents Department

Porous spherical shells and microspheres by electrodispersion precipitation

Description: The ability to reproduce the synthesis of dense- and porous-microspheres and micron-sized spherical shells is very important in (a) the development of ceramics for structural, electronic, catalyst and thermal applications; and (b) the encapsulation of products for controlled-release of drugs, flavors and perfumes, and inks and dyes, and the protection of light-sensitive components and mechanical support of fragile materials. Larger metallic- and ceramic-spherical shells have been used in inertial confinement fusion (ICF) experiments and as catalyst supports. The current paper will focus on a recent technique that has been developed for synthesizing ceramic microspheres and micro-shells. Pulsed electric fields have been used to enhance the dispersion of aqueous metal (Zr and Al) salt solutions from a nozzle and into a nonconducting liquid continuous phase that is immiscible with the aqueous phase. The diameter of the resulting microdroplets ranged in size from approximately 0.1 to 10 {mu}m. Precipitation of hydrous metal oxides occurred as ammonia, which was dissolved in varying amounts in the continuous phase, diffused into the aqueous microdroplets. Spherical shells were formed at higher ammonia concentrations and microspheres were produced at lower ammonia concentrations. Upon drying, dimples appeared in the particles that were synthesized at higher ammonia concentrations. The latter result accords with the well known fact that under certain conditions spherical shells collapse when a fluid is extracted from the core of the particle. No dimples were observed in the microspheres that were produced at lower ammonia concentrations. Analog X-ray dot maps for aluminum and zirconium were done to determine the spatial distribution of each metal in the particles.
Date: December 31, 1994
Creator: Harris, M.T.; Sisson, W.G.; Basaran, O.A.; Hayes, S.M. & Bobrowski, S.J.
Partner: UNT Libraries Government Documents Department

The future of finite element applications on massively parallel supercomputers

Description: The current focus in large scale scientific computing is upon parallel supercomputers. While still relatively unproven, these machines are being slated for production-oriented, general purpose supercomputing applications. The promise, of course, is to use massively parallel computers to venture further into scientific realisms by performing computations with anywhere from 10{sup 6} to 10{sup 9} grid points thereby, in principle, obtaining a deeper understanding of physical processes. In approaching this brave new world of computing with finite element applications, many technical issues become apparent. This paper attempts to reveal some of the applications-oriented issues which are facing code developers and ultimately the users of engineering and scientific applications on parallel supercomputers, but which seem to be remaining unanswered by vendors, researchers and centralized computing facilities. At risk is the fundamental way in which analysis is performed in a production sense, and the insight into physical problems which results. while at first this treatise may seem to advocate traditional register-to-register vector supercomputers, the goal of this paper is simply an attempt to point out what is missing from the massively parallel computing picture not only for production finite element applications, but also for grand challenge problems. the limiting issues for the use of FEM applications on parallel supercomputers are centered about the need for adequate disk space, archival storage, high bandwidth networks, and continued software development for mesh generation, scientific visualization, linear equation solvers and parallel input/output.
Date: July 5, 1994
Creator: Christon, M.
Partner: UNT Libraries Government Documents Department

Status report on the Holifield Radioactive Ion Beam Project

Description: In July 1992, a project was started to reconfigure the Holifield Heavy Ion Research Facility (HHIRF) to form the Holifield Radioactive Ion Beam Facility (HRIBF). This ORNL project to produce medium-intensity, proton-rich, radioactive ion beams (RIBS) for astrophysics, nuclear physics, and applied research was first described to the SNEAP community at Chalk River in 1992. To briefly review, radioactive ions will be produced by light ion beams from the Oak Ridge Isochronous Cyclotron (ORIC) striking a target in an Isotope Separator On-Line (ISOL)-type target-ion source assembly. The radioactive ions will be converted to negative ions either directly in the ion source or by charge exchange following positive ionization. After acceleration to approximately 300 keV, these ions will be injected into the tandem accelerator for acceleration to higher energies. Successful production and acceleration of RIBs requires changes in the existing accelerators, development of the target-ion source, and construction of a new high-voltage injector and new injection beam line for the tandem accelerator. A floor plan of the facility as it should be when the project is finished is given. Progress has been made in a areas and will be detailed starting with the cyclotron.
Date: December 31, 1994
Creator: Meigs, M.J.; Alton, G.D. & Auble, R.L.
Partner: UNT Libraries Government Documents Department

Micron-scale resolution radiography of laser-accelerated and laser-exploded foils using an yttrium x-ray laser

Description: The authors have imaged laser-accelerated foils and exploding foils on the few-micron scale using an yttrium x-ray laser (155 {angstrom}, 80 eV, {approximately}200 ps duration) and a multilayer mirror imaging system. At the maximum magnification of 30, resolution was of order one micron. The images were side-on radiographs of the foils. Accelerated foils showed significant filamentation on the rear-side (away from the driving laser) of the foil, although the laser beam was smoothed. In addition to the narrow rear-side filamentation, some shots revealed larger-scale plume-like structures on the front (driven) side of the Al foil. These plumes seem to be little-affected by beam smoothing and are likely a consequence of Rayleigh-Taylor instability. The experiments were carried out at the Nova two-beam facility.
Date: September 1, 1994
Creator: Cauble, R.; Da Silva, L.B.; Barbee, T.W. Jr.; Celliers, P.; Moreno, J.C.; Mrowka, S. et al.
Partner: UNT Libraries Government Documents Department

High temperature alkali corrosion of ceramics in coal gas: Final report

Description: There are several ceramic materials which are currently being considered for use as structural elements in coal combustion and coal conversion systems because of their thermal and mechanical properties. These include alumina (refractories, membranes, heat engines); silicon carbide and silicon nitride (turbine engines, internal combustion engines, heat exchangers, particulate filters); zirconia (internal combustion engines, turbine engines, refractories); and mullite and cordierite (particulate filters, refractories, heat exchangers). High temperature alkali corrosion has been known to cause premature failure of ceramic components used in advanced high temperature coal combustion systems such as coal gasification and clean-up, coal fired gas turbines, and high efficiency heat engines. The objective of this research is to systematically evaluate the alkali corrosion resistance of the most commonly used structural ceramics including silicon carbide, silicon nitride, cordierite, mullite, alumina, aluminum titanate, and zirconia. The study consists of identification of the alkali reaction products and determination of the kinetics of the alkali reactions as a function of temperature and time. 145 refs., 29 figs., 12 tabs.
Date: December 31, 1994
Creator: Pickrell, G.R.; Sun, T. & Brown, J.J. Jr.
Partner: UNT Libraries Government Documents Department

The National Ignition Facility Project

Description: The mission of the National Ignition Facility is to achieve ignition and gain in ICF targets in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effect testing, and for civilian applications such as fusion energy development and fundamental studies of matter at high temperatures and densities. This paper reviews the design, schedule and costs associated with the construction project.
Date: June 16, 1994
Creator: Paisner, J.A.; Campbell, E.M. & Hogan, W.J.
Partner: UNT Libraries Government Documents Department

Review of project definition studies of possible on-site uses of superconducting super collider assets and facilities. Final report

Description: This document reports on the results of a peer review and evaluation of studies made of potential uses of assets from the terminated Superconducting Super Collider (SSC) project. These project definition studies focused on nine areas of use of major assets and facilities at the SSC site near Waxahachie, Texas. The studies were undertaken as part of the effort to maximize the value of the investment made in the SSC and were supported by two sets of grants, one to the Texas National Research Laboratory Commission (TNRLC) and the second to various universities and other institutions for studies of ideas raised by a public call for expressions of interest. The Settlement Agreement, recently signed by the Department of Energy (DOE) and TNRLC, provides for a division of SSC property. As part of the goal of maximizing the value of the SSC investment, the findings contained in this report are thus addressed to officials in both the Department and TNRLC. In addition, this review had several other goals: to provide constructive feedback to those doing the studies; to judge the benefits and feasibility (including funding prospects) of the projects studied; and to help worthy projects become reality by matching projects with possible funding sources.
Date: December 1, 1994
Partner: UNT Libraries Government Documents Department

Utilization of surface-treated rubber particles from waste tires

Description: During a 12-month program, the author successfully demonstrated commercial applications for surface-treated rubber particles in two major markets: footwear (shoe soles and components) and urethane-foam carpet underlay (padding). In these markets, he has clearly demonstrated the ease of using R-4080 and R-4030 surface-treated rubber particles in existing manufacturing plants and processes and have shown that the material meets or exceeds existing standards for performance, quality, and cost-effectiveness. To produce R-4080 and R-4030, vulcanized rubber, whole-tire material is finely ground to particles of nominal 80 and mesh size respectively. Surface treatment is achieved by reacting these rubber particles with chlorine gas. In this report, the author describes the actual test and evaluations of the participant companies, and identifies other potential end uses.
Date: December 1, 1994
Creator: Smith, F.G.
Partner: UNT Libraries Government Documents Department

Progress in development of high temperature superconducting wire for electric power applications

Description: The technology of high temperature superconductivity has gone beyond mere scientific curiosity and into the manufacturing environment. Single lengths of multifilamentary wire are now produced that are over 200 meters long and that carry over 13 amperes at 77 K. Short-sample critical current densities approach 5 x 10{sup 4} A/cm{sup 2} at 77 K. Conductor requirements such as high critical current density in a magnetic field, strain-tolerant sheathing materials, and other engineering properties are addressed. A new process for fabricating round BSCCO-2212 wire has produced wires with critical current densities as high as 165,000 A/cm{sup 2} at 4.2 K and 53,000 A/cm{sup 2} at 40 K. This process eliminates the costly, multiple pressing and rolling steps that are commonly used to develop texture in the wires. New multifilamentary wires with strengthened sheathing materials have shown improved yield strengths up to a factor of five better than those made with pure silver. Many electric power devices require the wire to be formed into coils for production of strong magnetic fields. Requirements for coils and magnets for electric power applications are described.
Date: December 31, 1994
Creator: Hawsey, R.A.; Sokolowski, R.S.; Haldar, P. & Motowidlo, L.R.
Partner: UNT Libraries Government Documents Department

Developments in the electron gun simulation program, EGUN

Description: This paper discusses the developments in the electron gun simulation programs that are based on EGUN with its derivatives and supporting programs. Much of the code development has been inspired by technology changes in computer hardware; the implications of this evolution on EGN2 are discussed. Some examples and a review of the capabilities of the EGUN family are described.
Date: November 1, 1994
Creator: Herrmannsfeldt, W.B.
Partner: UNT Libraries Government Documents Department