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Influence of E{times}B and {nabla}{ital B} deift terms in 2-D edge/SOL transport simulations

Description: Classical particle drifts across the magnetic field can play an important role in tokamak edge-plasma transport. The relative influence of these terms is studied for self-consistent simulations by including them, together with anomalous diffusion transport, in a 2-D fluid model of edge-plasma transport for the DIII-D tokamak geometry. The drifts cause asymmetries in the plasma equilibrium which depend on the direction of the magnetic field, B. The basic results can be understood by dividing the drifts into three categories: diamagnetic, E x B, and {nabla}B. The dominant effect near the divertor plates is from the E x B drifts, while the weaker {nabla}B drifts cause an increase in the magnitude of the radial electric field inside the magnetic separatrix. The diamagnetic terms, defined as divergence free, do not contribute to transport.
Date: May 15, 1998
Creator: Rognlien, T. D., LLNL

Injection System

Description: Felton Medical identified a market need for a handheld portable single shot needleless injection system. This market need was being driven by a global need to eliminate the hazards of medical needle disposal by providing an alternative injection method. Felton Medical brought to this partnership individuals experienced in the research, development, design, assembly, marketing, and servicing of precision animal health medical devices. AlliedSignal provided manufacturing understanding and a facility proficient in product development for small precision mechanical parts and assemblies.
Date: June 15, 1998
Creator: Thomas, J.E.

Investigation of properties and performance of ceramic composite components: Final report on Phases 3 and 4

Description: The objective of the Fossil Energy Advanced Research and Technology Development (AR and TD) Materials Program is to conduct research and development on materials for longer-term fossil energy applications as well as for generic needs of various fossil fuel technologies. The research program of the Materials Response Group at Virginia Tech addresses the need for reliable and durable structural ceramic composites to perform in high temperature environments. The research effort provides an experimental and analytical basis for the transition from properties of materials to performance of actual component structures. Phases 1 and 2 of the present program focused on the development of test capabilities, initial studies of component mechanical response under various conditions and the development of a life prediction methodology. These efforts have been described in previous reports. This report summarizes the major tasks completed under Phases 3 and 4 of the project. Overall, the authors have made significant progress in a broad spectrum of tasks in this program. Their efforts have encompassed component evaluation, assessment of new SiC-based composites with improved high-temperature potential, development of oxide coating materials for SiC, and the extension and development of new models for predicting the durability of composite components under specific operating conditions for various CMC applications. Each of these areas of work is an important area for achieving the ultimate goal of usable SiC-based composites in high-temperature corrosive environments typical of fossil energy applications.
Date: January 15, 1998
Creator: Curtin, W.A.; Halverson, H.; Carter, R.H.; Miraj, N. & Reifsnider, K.L.

Investigation of syngas interactions in alcohol synthesis catalyst

Description: The primary objectives of the project are to (a) synthesize, by controlled sequential and co-impregnation techniques, three distinct composition metal clusters (consisting of Cu-Co-Cr and Cu-Fe-Zn): rich in copper (Methanol selective), rich in ferromagnetic metal (Co or Fe-Hydrocarbon selective) and intermediate range (mixed alcohol catalysts); (b) investigate the changes in the magnetic character of the systems due to interaction with CO, through Zero-field Nuclear Magnetic Resonance (ZFNMR) study of cobalt and Magnetic character (saturation magnetization and coercive field) analysis of the composite catalyst of Vibrating Sample Magnetometry (VSM); (c) examine the changes in syngas adsorption character of the catalyst as the composition changes, by FTIR Spectroscopic analysis of CO stretching frequencies; (d) determine the nature and size of these intermetallic clusters by Scanning Electron Microscopy (SEM); and (e) perform catalytic runs on selected samples and analyze the correlations between the physical and chemical characteristics. The catalysts chosen have a greater promise for industrial application than the Rh and Mo based catalysts. Several groups preparing catalysts by synthetic routes have reported divergent results for activity and selectivity. Generally the research has followed an empirical path and less effort is devoted to analyze the mechanisms and the scientific basis. The primary intent of this study is to analyze the nature of the intermetallic and gas-metal interactions and examine the correlations to catalytic properties.
Date: April 15, 1998
Creator: Akundi, M.A.

Investigations of plutonium immobilization into the vitreous compositions

Description: Development and characterizations of phosphate and borosilicate glasses for vitrifying high level waste (HLW) solutions in Russia has been extensive. The technical data generated were for low concentrations (less than 0.05% Pu) of plutonium. Limited studies have been performed with plutonium concentrations one to two orders of magnitude larger. The results of these studies are being used to plan and implement an expanded experimental program to establish the limitations and characteristics of plutonium in similar glass compositions.
Date: April 15, 1998
Creator: Matyunin, Y.I.,

Isotopic Shifts in a Polaronic System

Description: The effect of isotopic substitution in a model polaronic system is presented. The authors use a three-site many body electron-phonon model which includes electronic correlations and electron-phonon interactions, showing the presence of polaron tunneling for intermediate and strong couplings. The isotopic substitution changes the dynamics of polaron tunneling. Additionally in the intermediate electron-phonon coupling regime, relevant for high-Tc superconductors, a change in the local structure is predicted. In this regime, the isotopic shift of phonon excitations is consistent with results of optical measurements of c-axis phonons in YBa{sub 2}Cu{sub 3}O{sub 7}.
Date: June 15, 1998
Creator: de Leon, J.M.; de Coss, R.; Rubia-Ponce, A.; Bishop, A.R. & Trugman, S.A.

Kinetic information from detonation front curvature

Description: The time constants for time-dependent modeling may be estimated from reaction zone lengths, which are obtained from two sources One is detonation front curvature, where the edge lag is close to being a direct measure The other is the Size Effect, where the detonation velocity decreases with decreasing radius as energy is lost to the cylinder edge A simple theory that interlocks the two effects is given A differential equation for energy flow in the front is used, the front is described by quadratic and sixth-power radius terms The quadratic curvature comes from a constant power source of energy moving sideways to the walls Near the walls, the this energy rises to the total energy of detonation and produces the sixth-power term The presence of defects acting on a short reaction zone can eliminate the quadratic part while leaving the wall portion of the cuvature A collection of TNT data shows that the reaction zone increases with both the radius and the void fraction
Date: June 15, 1998
Creator: Souers, P. C., LLNL

Laser sampling system for an inductively-coupled atomic emission spectrometer. Final report

Description: A laser sampling system was attached to a Perkin Elmer Optima 3000 inductively-coupled plasma, atomic emission spectrometer that was already installed and operating in the Chemistry and Geochemistry Department at the Colorado School of Mines. The use of the spectrometer has been highly successful. Graduate students and faculty from at least four different departments across the CSM campus have used the instrument. The final report to NSF is appended to this final report. Appendices are included which summarize several projects utilizing this instrument: acquisition of an inductively-coupled plasma atomic emission spectrometer for the geochemistry program; hydrogen damage susceptibility assessment for high strength steel weldments through advanced hydrogen content analysis, 1996 and 1997 annual reports; and methods for determination of hydrogen distribution in high strength steel welds.
Date: February 15, 1998

Laser ultrasonic furnace tube coke monitor. Quarterly technical progress report No. 1, May 1--August 1, 1998

Description: The overall aim of the project is to demonstrate the performance and practical use of a laser ultrasonic probe for measuring the thickness of coke deposits located within the high temperature tubes of a thermal cracking furnace. This aim will be met by constructing an optical probe that will be tested using simulated coke deposits that are positioned inside of a bench-scale furnace. Successful development of the optical coke detector will provide industry with the only available method for on-line measurement of coke deposits. The optical coke detector will have numerous uses in the refining and petrochemical sectors including monitoring of visbreakers, hydrotreaters, delayed coking units, vacuum tower heaters, and various other heavy oil heating applications where coke formation is a problem. The coke detector will particularly benefit the olefins industry where high temperature thermal crackers are used to produce ethylene, propylene, butylene and other important olefin intermediates. The ethylene industry requires development of an on-line method for gauging the thickness of coke deposits in cracking furnaces because the current lack of detailed knowledge of coke deposition profiles introduces the single greatest uncertainty in the simulation and control of modern cracking furnaces. The laser ultrasonic coke detector will provide operators with valuable new information allowing them to better optimize the decoking turnaround schedule and therefore maximize production capacity.
Date: August 15, 1998

Light Machines Operator Performance Support System

Description: The objective of this project was to create a multimedia operator performance support system (OPSS) shell that would provide a framework for delivering appropriate information to the student/novice machine tool user just when needed and in the most appropriate form. In addition, the program was designed so that it could be expanded and further developed by Light Machines personnel. The expertise of AlliedSignal Federal Manufacturing and Technologies (ASFM and T) in the areas of performance support system design and multimedia creation was employed to create the most user-friendly graphical user interface (GUI) while providing access to key topical areas. Light Machines provided a subject matter expert from their technical services group in order to provide the needed information for structuring the OPSS shell. They also provided a Benchman VMC 4000 machine tool at the ASFM and T New Mexico location as well as specific instruction on the safe and effective use of that machine tool.
Date: June 15, 1998
Creator: Bohley, M.C.

Linear stability of an accelerated wire array

Description: The linear stability of an array of a large number of thin wires is considered. The wires form a cylindrical surface which is accelerated towards the axis under the action of a current excited in the array by an external source. General equations governing stability of this system are derived and a complete classification of all the modes present in such a system is presented. In agreement with an earlier analysis by Felber and Rostoker, it is shown that there exist two types of modes: medial modes, in which the wires experience deformation in the rz plane, and lateral modes, in which only a purely azimuthal deformation is present. For a given axial wave number k, the maximum growth rate for medial perturbations corresponds to a mode in which all the wires move �in phase� (an analog of an axisymmetric mode for a continuous cylindrical shell), whereas for the lateral perturbations the maximum growth rate corresponds to the opposite displacements of the neighboring wires. Numerical analysis of a dispersion relation for a broad range of modes is presented: Some limiting cases are discussed. In particular, it is shown that a traditional k�� scaling holds until surprisingly high wave numbers, even exceeding the inverse inter- wire distance. In the limit of long-wavelength perturbations, a model of a continuous shell becomes valid; the presence of the wires manifests itself in this model by a strong anisotropy of electrical conductivity, high along the wires and vanishing across the wires. The resulting modes differ considerably from the modes of a thin perfectly conducting shell. In particular, a new mode of �zonal flows� is identified.
Date: October 15, 1998
Creator: Hammer, J H & Ryutov, D D

Low-(18)O Silicic Magmas: Why Are They So Rare?

Description: LOW-180 silicic magmas are reported from only a small number of localities (e.g., Yellowstone and Iceland), yet petrologic evidence points to upper crustal assimilation coupled with fractional crystallization (AFC) during magma genesis for nearly all silicic magmas. The rarity of 10W-l `O magmas in intracontinental caldera settings is remarkable given the evidence of intense 10W-l*O meteoric hydrothermal alteration in the subvolcanic remnants of larger caldera systems. In the Platoro caldera complex, regional ignimbrites (150-1000 km3) have plagioclase 6180 values of 6.8 + 0.1%., whereas the Middle Tuff, a small-volume (est. 50-100 km3) post-caldera collapse pyroclastic sequence, has plagioclase 8]80 values between 5.5 and 6.8%o. On average, the plagioclase phenocrysts from the Middle Tuff are depleted by only 0.3%0 relative to those in the regional tuffs. At Yellowstone, small-volume post-caldera collapse intracaldera rhyolites are up to 5.5%o depleted relative to the regional ignimbrites. Two important differences between the Middle Tuff and the Yellowstone 10W-180 rhyolites elucidate the problem. Middle Tuff magmas reached water saturation and erupted explosively, whereas most of the 10W-l 80 Yellowstone rhyolites erupted effusively as domes or flows, and are nearly devoid of hydrous phenocrysts. Comparing the two eruptive types indicates that assimilation of 10W-180 material, combined with fractional crystallization, drives silicic melts to water oversaturation. Water saturated magmas either erupt explosively or quench as subsurface porphyrins bejiire the magmatic 180 can be dramatically lowered. Partial melting of low- 180 subvolcanic rocks by near-anhydrous magmas at Yellowstone produced small- volume, 10W-180 magmas directly, thereby circumventing the water saturation barrier encountered through normal AFC processes.
Date: October 15, 1998
Creator: Balsley, S.D. & Gregory, R.T.

Magnetic anisotropy and its microstructural origin in epitaxially grown SmCo thin films.

Description: Microstructural features and magnetic behavior of epitaxially grown SmCo thin films with very high in-plane anisotropy are presented. Transmission electron microscopy was used to characterize the microstructure while magnetic measurements were performed using dc and SQUID magnetometers. Two substrate orientations were studied, i.e., MgO(100)/Cr(100)/SmCo(11{bar 2}0) and MgO(110)/Cr(211)/SmCo(1{bar 1}00). In the former, the SmCo(11{bar 2}0) film shows a bicrystalline microstructure, whereas in the latter, a uniaxial one is observed. Both microstructure consist of grains with a mixture of SmCo{sub 3} , Sm{sub 2}Co{sub 7} and SmCo{sub 3} polytypoids. A deviation from the c-axes was observed in the in-plane anisotropy of the SmCo(11{bar 2}0) thin film. A strong exchange interaction between the grains would, in principle, explain the observed deviation. On the other hand, both SmCo(11{bar 2}0) and (1{bar 1}00) thin films show very high coercivity values with pinning-type characteristics. Possible coercivity mechanisms related to intergranular exchange interactions and local variation in magnetocrystalline anisotropy constants are discussed.
Date: April 15, 1998
Creator: Benaissa, M.

Managing America's solid waste

Description: This report presents an historical overview of the federal role in municipal solid waste management from 1965 to approximately 1995. Attention is focuses on the federal role in safeguarding public health, protecting the environment, and wisely using material and energy resources. It is hoped that this report will provide important background for future municipal solid waste research and development initiatives.
Date: September 15, 1998
Creator: Phillips, J. A.

Manipulation of Biofilm Microbial Ecology

Description: The biofilm mode of growth provides such significant advantages to the members of the consortium that most organisms in important habitats are found in biofilms. The study of factors that allow manipulation of biofilm microbes in the biofilm growth state requires that reproducible biofilms be generated. The most effective monitoring of biofilm formation, succession and desaturation is with on-line monitoring of microbial biofilms with flowcell for direct observation. The biofilm growth state incorporates a second important factor, the heterogeneity in distribution in time and space of the component members of the biofilm consortium. This heterogeneity is reflected not only in the cellular distribution but in the metabolic activity within a population of cells. Activity and cellular distribution can be mapped in four dimensions with confocal microscopy, and function can be ascertained by genetically manipulated reporter functions for specific genes or by vital stains. The methodology for understanding the microbial ecology of biofilms is now much more readily available and the capacity to manipulate biofilms is becoming an important feature of biotechnology.
Date: August 15, 1998
Creator: White, D.C.; Palmer, R.J., Jr.; Zinn, M.; Smith, C.A.; Burkhalter, R.; Macnaughton, S.J. et al.

Market-Driven EFG Modules, Annual Subcontract Report, 14 December 1996 - 13 February 1998

Description: This report summarizes the progress made at ASE Americas Inc. during Phase II of this subcontract. Accomplishments under Task 4: Wafers include optimization of edge-defined film-fed growth (EFG) crystal growth variables, leading to reduced crystal stresses and improved wafer flatness; increased die run length due to improvements in the design of furnace components; construction and testing of EFG growth furnace enclosure; reduction of EFG wafer thickness from 300 {micro}m for 50% of all standard production material; implementation of new equipment to reduce costs of silicon feedstock sorting prior to EFG crystal growth with a 3% increase in silicon feedstock utilization; and development work demonstrating the laser cutting of EFG wafers at higher speeds and with reduced silicon damage. Accomplishments under Task 5: Cells include characterization of cells after diffusion as preliminary work toward improving diffusion conditions and improving cell efficiency; demonstration of a continuous process to remove phosphorus glass from diffused wafers, reducing chemical consumption and hazardous waste by 98%; development of statistical process control methods to improve cell production process control; the use of design of experiments to study interactions between processing at various steps in cell manufacturing, and to develop strategies for productivity improvements; improvements in EFG cell efficiency due to the reduction in average wafer thickness; design and construction of equipment for producing cells with an improved grid design; and demonstration of average efficiencies over 14.1% on production lots of EFG cells. Accomplishments under Task 6: Modules include production and successful testing of prototypes of a lower-cost module diode housing; successful demonstration of a module design that greatly improves collection of light from space between cells in modules; testing of new encapsulants and lamination processes to demonstrate reduced lamination time, improved yield and enhanced durability; and completion of options study for lower-cost module frames, and development of ...
Date: December 15, 1998
Creator: Kardauskas, M. & Kalejs, J. (ASE Americas, Inc., Billerica, Massachusetts)


Description: The present work is about the algorithms and parallel constructs of a spectral element equatorial ocean model. It shows that high order domain decomposition ocean models can be efficiently implemented on massively parallel architectures, such as the Connection Machine Model CM5. The optimized computational efficiency of the parallel spectral element ocean model comes not only from the exponential convergence of the numerical solution, but also from the work-intensive, medium-grained, geometry-based data parallelism. The data parallelism is created to efficiently implement the spectral element ocean model on the distributed-memory massively parallel computer, which minimizes communication among processing nodes. Computational complexity analysis is given for the parallel algorithm of the spectral element ocean model, and the model's parallel performance on the CM5 is evaluated. Lastly, results from a simulation of wind-driven circulation in low-latitude Atlantic ocean are described.
Date: July 15, 1998

Material protection, control and accounting cooperation at the Urals Electrochemical Integrated Plant (UEIP), Novouralsk, Russia

Description: The Urals Electrochemical Integrated Plant is one of the Russian Ministry of Atomic Energy`s nuclear material production sites participating in the US Department of Energy`s Material Protection, Control and Accounting (MPC&A) Program. The Urals Electrochemical Integrated Plant is Russia`s largest uranium enrichment facility and blends tons of high-enriched uranium into low enriched uranium each year as part of the US high-enriched uranium purchase. The Electrochemical Integrated Plant and six participating national laboratories are cooperating to implement a series of enhancements to the nuclear material protection, control, and accountability systems at the site This paper outlines the overall objectives of the MPC&A program at Urals Electrochemical Integrated Plant and the work completed as of the date of the presentation.
Date: July 15, 1998
Creator: McAllister, S., LLNL

Materials disposition plutonium acceptance specifications for the immobilization project

Description: The Department of Energy (DOE) has declared approximately 38.2 tonnes of weapons-grade plutonium to be excess to the needs of national security, 14.3 tonnes of fuel- and reactor-grade plutonium excess to DOE needs, and anticipates an additional 7 tonnes to be declared excess to national security needs. Of this 59.5 tonnes, DOE anticipates that ~ 7.5 tonnes will be dispositioned as spent fuel at the Geologic Repository and ~ 2 tonnes will be declared below the safeguards termination limit and be discarded as TRU waste at WIPP. The remaining 50 tonnes of excess plutonium exists in many forms and locations around the country, and is under the control of several DOE Offices. The Materials Disposition Program (MD) will be receiving materials packaged by these other Programs to disposition in a manor that meets the �spent fuel standard.� For disposition by immobilization, the planned facilities will have only limited capabilities to remove impurities prior to blending the plutonium feedstocks to prepare feed for the plutonium immobilization ceramic formation process, Technical specifications are described here that allow potential feedstocks to be categorized as either acceptable for transfer into the MD Immobilization Process, or unacceptable without additional processing prior to transfer to MD. Understanding the requirements should allow cost benefit analyses to be performed to determine if a specific material should be processed sufficiently shipment to WIPP. Preliminary analyses suggest that about 45 tonnes of this material have impurity concentrations much lower than the immobilization acceptance specifications. In addition, approximately another 3 tonnes can easily be blended with the higher purity feeds to meet the immobilization specifications. Another 1 tonne or so can be processed in the immobilization plutonium conversion area to yield materials that can be blended to provide acceptable feed for immobilization. The remaining 3 tonnes must be excluded in their ...
Date: June 15, 1998
Creator: Ebbinghaus, B.; Edmunds, T. A.; Gray, L.; Riley, D. C. & Vankonynenburg, R. A.