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Logistics for the implementation of lead-free solders on electronic assemblies

Description: The prospects of legislative and regulatory action aimed at taxing, restricting or banning lead-bearing materials from manufactured products has prompted the electronics community to examine the implementation of lead-free solders to replace currently used lead-containing alloys in the manufacture of electronic devices and assemblies. The logistics for changing the well established ``tin-lead solder technology`` require not only the selection of new compositions but also the qualification of di… more
Date: December 31, 1993
Creator: Vianco, P. T. & Artaki, I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance of CVR coatings for PBR fuels

Description: As part of the component development process for the particle bed reactor (PBR), it is necessary to develop coatings for fuel particles which will be time and temperature stable. These coatings must not only protect the particle from attack by the hydrogen coolant, but must also help to maintain the bed in a coolable geometry and mitigate against fission product release. In order to develop these advanced coatings, a process to produce chemical vapor reaction (CVR) coatings on fuel for PBRs has… more
Date: December 31, 1993
Creator: Adams, J. W.; Barletta, R. E.; Svandrlik, J. & Vanier, P. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear disarmament verification

Description: Arms control treaties, unilateral actions, and cooperative activities -- reflecting the defusing of East-West tensions -- are causing nuclear weapons to be disarmed and dismantled worldwide. In order to provide for future reductions and to build confidence in the permanency of this disarmament, verification procedures and technologies would play an important role. This paper outlines arms-control objectives, treaty organization, and actions that could be undertaken. For the purposes of this Wor… more
Date: December 31, 1993
Creator: DeVolpi, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal treatment of high explosives at Mason & Hanger/Pantex Plant

Description: The Pantex plant presently processes about 45,000 kg (100,000 lb) of high explosives annually by outdoor burning. About half of the explosives are weapon components weighing over 5 kg (10 lb) which come directly out of nuclear weapons being removed from the stockpile. The other half is generated from various support processes, special tests, etc. Burning serves the three-fold purpose of demilitarizing, removing all classified characteristics, and eliminating the severe hazard posed by the explo… more
Date: December 31, 1993
Creator: Patterson, W. E. & Phelan, P. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A comparison of the evolution of cold and hot deformation microstructures and textures in fcc metals

Description: Microstructures and textures which develop during cold deformation are compared to those which develop during hot deformation. This comparison is made using the evolutionary framework of grain subdivision and the formation of low energy dislocation structures. During deformation grains are subdivided into differently deforming regions separated by geometrically necessary dislocation boundaries. These boundaries include dense dislocation walls, microbands, lamellar boundaries and subgrains. Grai… more
Date: December 31, 1993
Creator: Hughes, D. A. & Hansen, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solar neutrino experiments: An update

Description: The situation in solar neutrino physics has changed drastically in the past few years, so that now there are four neutrino experiments in operation, using different methods to look at different regions of the solar neutrino energy spectrum. These experiments are the radiochemical {sup 37}Cl Homestake detector, the realtime Kamiokande detector, and the different forms of radiochemical {sup 71}Ga detectors used in the GALLEX and SAGE projects. It is noteworthy that all of these experiments report… more
Date: December 31, 1993
Creator: Hahn, R. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies in physico-chemical hydrodynamics of extended systems. Annual progress report, November 1, 1993--October 31, 1994

Description: The object of the proposed research program is a unified theoretical approach to the description of a variety of physico-chemical hydrodynamic systems characterized by a significant disparity between the spatial scales involved. By appropriately performed averaging over short scales, one may considerably simplify the original problem, sometimes even lowering its effective dimensionality, and thereby making the latter quite tractable either analytically or numerically. Specifically, the author p… more
Date: December 31, 1993
Creator: Sivashinsky, G. I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Consolidated incineration facility technical support

Description: In 1996, the Savannah River Site plans to begin operation of the Consolidated Incineration Facility (CIF) to treat solid and liquid RCRA hazardous and mixed wastes. The Savannah River Technology Center (SRTC) leads an extensive technical support program designed to obtain incinerator and air pollution control equipment performance data to support facility start-up and operation. Key components of this technical support program include recently completed waste burn tests at both EPA`s Incinerati… more
Date: December 31, 1993
Creator: Burns, D. & Looper, M. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Inorganic polymer-derived ceramic membranes

Description: Polymeric silica sols were used to prepare membranes on commercial {gamma}-A1{sub 2}O{sub 3} supports. Aging of the silica sols was shown to be effective to form discrete membrane layers. He/N{sub 2} selectivity factors exceeding ideal Knudsen values were observed when the sols were prepared under conditions in which the condensation rate was minimized. It is proposed that the average pore size of the membrane depends on the balance of capillary pressure and modulus during membrane deposition a… more
Date: December 31, 1993
Creator: Brinker, C. J.; Sehgal, R.; Raman, N.; Schunk, P. R. & Headley, T. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stability and precipitation kinetics in Si{sub 1{minus}y}C{sub y}/Si and Si{sub 1{minus}x{minus}y}Ge{sub x}C{sub y}/Si heterostructures prepared by solid phase epitaxy

Description: This study investigates the stability of metastable Si{sub 1{minus}y}C{sub y}/Si heterostructures during rapid thermal annealing (RTA) over a temperature range of 1,000--1,150 C. Heterostructures of Si{sub 1{minus}y}C{sub y}/Si and Si{sub 1{minus}x{minus}y}Ge{sub x}C{sub y}/Si (x {equals} 0.77, Y {<=} .0014) were formed by solid phase epitaxy from C implanted, preamorphized substrates using a 30 minute 700 C anneal in N{sub 2}. The occupancy of C in substitution lattice sites was monitored by F… more
Date: December 31, 1993
Creator: Strane, J. W.; Picraux, S. T.; Stein, H. J.; Lee, S. R.; Candelaria, J.; Theodore, D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Demonstration testing and evaluation of in situ soil heating: Management Plan

Description: This document is the Management Plan for US DOE contract entitled, {open_quotes}Demonstration, Testing and Evaluation of In Situ Soil Heating,{close_quotes} Contract No. DE-AC05-93OR22160, IITRI Project No. C06787. In this project IITRI will demonstrate an in situ soil heating technology for the removal of hazardous organic contaminants present in the soil. In situ heating will be accomplished by the application of 60 Hz ac power to the soil. The soil will be heated to a temperature of about 90… more
Date: December 31, 1993
Creator: Dev, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design optimization analysis of the new SPR III-M reactor

Description: This report discusses the finite element method analysis which was used to refine the SPR III-M reactor fuel assembly mechanical design to withstand the stresses and strains of pulse-mode operation, which induces thermal shock loading in the fuel assembly components. The original reactor design was analyzed for its structural response to separate pulses at increasingly severe levels. Subsequent calculations at one consistent pulse level examined several design modifications, which will result i… more
Date: December 31, 1993
Creator: Miller, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Review of lithium-ion technology

Description: The first practical use of graphite intercalation compounds (GIC) as battery anodes was reported in a 1981 patent by Basu in which a molten salt cell was described having a negative electrode that consisted of lithium intercalated in graphite. A second patent by Basu, issued in 1983, described an ambient temperature rechargeable system which also utilized lithium intercalated in graphite as the anode. Work in this area progressed at a low level, however, until interest was sparked in 1990 when … more
Date: December 31, 1993
Creator: Levy, S. C. & Cieslak, W. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Moderator materials and neutronic performance

Description: The great variety of instruments proposed for LANSCE-II entails an equally varied set of requirements for the target stations moderators. Besides the obvious features such as intensity and pulse width of the neutron pulse, a number of more pragmatic questions have to be addressed such as fast neutron background and energy deposition in the moderators, especially at large proton beam powers such as the 1 MW proton beam power proposed for LANSCE-II.
Date: December 31, 1993
Creator: Daemen, L. L.; Russell, G. J.; Pitcher, E. J. & Lujan, M. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Collapse of Flux Tubes

Description: Flux tubes are one of the most elementary systems of quantum chromodynamics. They are the idealized configurations of heavy quark-antiquark pairs at large separations L such that the region between can be assumed to possess axial-cylindrical symmetry. They play a central role in lattice QCD calculations and in models of QCD, as well as in the phenomenology of QCD processes. Lattice QCD calculations on flux tubes are generally limited to the quenched approximation (no massless quarks) and allow … more
Date: December 31, 1993
Creator: Wilets, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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X-ray production with sub-picosecond laser pulses

Description: The interaction of intense, sub-picosecond laser pulses with solid targets produces intense picosecond x-ray pulses. With focused laser pulses of several 10 {sup 18} W/cm{sup 2}, He-like and H-like line radiation from targets such as aluminum and silicon has been produced. The energy conversion efficiency from the laser pulse energy to the 1--2 keV line x-rays is nearly one percent. The duration of the line x-ray radiation is of the order of ten picoseconds, although this may be an upper estima… more
Date: December 31, 1993
Creator: Schappert, G. T.; Cobble, J. A.; Fulton, R. D. & Kyrala, G. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance assessment of the Greater Confinement Disposal facility on the Nevada Test Site: Comparing the performance of two conceptual site models

Description: A small amount of transuranic (TRU) waste has been disposed of at the Greater Confinement Disposal (GCD) site located on the Nevada Test Site`s (NTS) Radioactive Waste Management Site (RWMS). The waste has been buried in several deep (37 m) boreholes dug into the floor of an alluvial basin. For the waste to remain in its current configuration, the DOE must demonstrate compliance of the site with the TRU disposal requirements, 40 CFR 191. Sandia`s approach to process modelling in performance ass… more
Date: December 31, 1993
Creator: Baer, T. A.; Price, L. L. & Gallegos, D. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New high temperature plasmas and sample introduction systems for analytical atomic emission and mass spectrometry. Progress report: January 1, 1993--December 31, 1993

Description: In this research, new high-temperature plasmas and new sample introduction systems are explored for rapid elemental and isotopic analysis of gases, solutions, and solids using mass spectrometry and atomic emission spectrometry. During the period January 1993--December 1993, emphasis was placed on (a) analytical investigations of atmospheric-pressure helium inductively coupled plasma (He ICP) that are suitable for atomization, excitation, and ionization of elements possessing high excitation and… more
Date: December 31, 1993
Creator: Montaser, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research activities of Martin C. Casdagli at SFI September 1989--May 1991

Description: My research over this period has focused on the theory and application of non-linear time series forecasting. The purpose of time series forecasting is to predict apparently random behavior about which we have little or no knowledge. A time series is a set of values that change in time, for example, daily stock market prices for a given set of firms, or the volume of the polar ice caps over the last two million years. Recent developments in the understanding of chaotic dynamical systems have st… more
Date: December 31, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dual-benefit technologies at Sandia National Laboratories

Description: What does the pulp and paper industry have in common with the desert southwest and nuclear weapons? As a representative of one of the Nations three nuclear weapons design laboratories (Los Alamos National Laboratory, Livermore National Laboratory and Sandia National Laboratories), my goal is to identify ``dual-benefit`` technologies where codevelopment will both strengthen the nation`s competitive position and enhance national security. In development of this presentation, I found more common e… more
Date: December 31, 1993
Creator: Schaefer, D. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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On the nature of striae in strontium barium niobate

Description: Strontium barium niobate crystals were grown by the Czochralski technique. These crystals were 15--20 mm in diameter and 25 to 75 mm long. Two types stride, designated as coarse and fine, were characterized. The coarse stride are optically dense and are spaced by 100 to 500 {mu}m apart; the fine striae are optically less dense and spaced 5--50 {mu}m apart. The origins of the stride are attributed to thermal fluctuations in the melt related to the control system and to rotation of the growing cr… more
Date: December 31, 1993
Creator: Monchamp, R. R.; Mihalik, G. B. & Franks, L. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of nucleation and growth in Al-Zn alloys using TEM

Description: Nucleation and growth studies were conducted on Al-Zn alloys at several temperatures using transmission electron microscopy (TEM) with an in-situ furnace. The value of the critical undercooling was established by noting the lowest temperature at which precipitates were no longer observed, following a quench into the two-phase metastable region. These results were compared with the Langer-Schwartz model of nucleation and growth in which it is predicted that the half-completion time (i.e, the tim… more
Date: December 31, 1993
Creator: Sundar, G.; Hoyt, J. J.; Kenik, E. A. & Spooner, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Target station design for a 1 MW pulsed spallation neutron source

Description: Target stations are vital components of the 1 MW, next generation spallation neutron source proposed for LANSCE. By and large, target stations design determines the overall performance of the facility. Many traditional concepts will probably have to be rethought, and many new concepts will have to be put forward to meet the 1 MW challenge. This article gives a brief overview of the proposed neutron spallation source from the target station viewpoint, as well as the general philosophy adopted fo… more
Date: December 31, 1993
Creator: Russell, G. J.; Baker, G. D. & Brewton, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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MRIVIEW: An interactive computational tool for investigation of brain structure and function

Description: MRIVIEW is a software system which uses image processing and visualization to provide neuroscience researchers with an integrated environment for combining functional and anatomical information. Key features of the software include semi-automated segmentation of volumetric head data and an interactive coordinate reconciliation method which utilizes surface visualization. The current system is a precursor to a computational brain atlas. We describe features this atlas will incorporate, including… more
Date: December 31, 1993
Creator: Ranken, D. & George, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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