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Applying the resources of a national laboratory to support US competitiveness: A focus on cooperative R & D agreements

Arvizu, D.E.

Recent legislation mandated the improvement of national competitiveness as a mission of the defense programs of the US Department of Energy. As a consequence, technology transfer --- the process of transferring commercially valuable technologies developed under government sponsorship to industry for commercialization --- is becoming an important emphasis at many DOE laboratories. Technology transfer processes take many forms, and there are different perspectives on how to approach this activity. In this paper, a taxonomy of technology transfer processes at a national laboratory is presented. In addition, the focus and rationale of Sandia National Laboratories' unique new initiative called the Technology Maturation Program is discussed. This program is designed to complete one essential element of technology transfer that advanced technologies toward commercial applications to the point that industry is willing to assume the investment risk. Strategies and program plans designed to improve the effectiveness of Sandia's contribution to enhancing US industry's competitive position in world markets are also presented.

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Effect of ENDF/B-VI cross sections on neutron dosimetry

Griffin, Patrick J.

ENDF/B-VI cross sections were released to the testing community in January 1990. Work at Sandia National Laboratories, with pre-released versions of the new cross sections indicates that changes in the neutron-induced charged-particle reactions will significantly affect 14-MeV neutron dosimetry. Reactions that are important for fission reactor dosimetry were examined and most did not change significantly. 12 refs., 3 figs., 3 tabs.

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Characterization of chemically prepared PZT thin films

Tuttle, Bruce T.

We have systematically varied processing parameters to fabricate PZT 53/47 thin films. Polycrystalline PZT thin films were fabricated by spin depositing Pt coated SiO{sub 2}/Si substrates with alkoxide solutions. Our study focused on two process parameters: (1) heating rate and (2) excess Pb additions. We used rapid thermal processing techniques to vary heating rates from 3{degree}C/min to 8400{degree}C/min. Films were characterized with the following excess Pb additions: 0, 3, 5, and 10 mol %. For all process variations, films with greater perovskite content had better ferroelectric properties. Our best films were fabricated using the following process parameters: an excess Pb addition of 5 mol %, a heating rate of 8400{degree}C/min and annealing conditions of 700{degree}C for 1 min. Films fabricated using these process conditions had a remanent polarization of 0.27 C/m{sup 2} and a coercive field of 3.4 MV/m. 12 refs., 4 figs.

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Lost circulation technology development projects

Glovka, D.A.

Lost circulation is the phenomenon where circulating drilling fluid is lost to fractures or pores in the rock formation rather than returning to the surface through the wellbore annulus. In geothermal drilling, lost circulation can be a serious problem that contributes greatly to the cost of the average geothermal well. A DOE-sponsored program is underway at Sandia National Laboratories to develop new technology for solving lost circulation problems. The Lost Circulation Technology Development Program currently consists of twelve projects in three areas: technology to plug porous and minor-fracture loss zones; technology to plug major-fracture loss zones; and technology to characterize loss zones. This paper describes the program and highlights recent progress. 12 refs., 10 figs.

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SEU characterization and design dependence of the SA3300 microprocessor

IEEE Transactions on Nuclear Science

Sexton, F.W.

The SEU vulnerability of the SA3300 16-bit microprocessor has been characterized, and the effects of two different design revisions on error rate have been explored. We found that the threshold for upset depends on the data pattern written into the general purpose registers. With all bits in the general purpose registers set to logic one, a design with 2-µm n- and p-channel transistor lengths had a threshold LET of 35 MeV-cm2/mg at 25°C and 4.5 volt operation. With all zero's stored in the registers the upset threshold increased by more than a factor of two to 83 MeV-cm2/mg. A second design revision, with 1.25-µm and 1.75-µm n- and p-channel transistor lengths, respectively, was more vulnerable to upset, but exhibited a smaller dependence on logic state. Measured threshold LET was 23 and 35 MeV-cm2/mg with all one's and all zero's, respectively. Microprobe measurements using a pulsed Nd:YAG laser suggest that the observed pattern dependence for both design revisions is due to bipolar photocurrent in a vertical n+pn transistor. A slight temperature dependence was observed in both design revisions. This is consistent with the use of oversized restoring transistors to minimize SEU vulnerability rather than polysilicon feedback resistors. More recent data show thresholds above 120 MeV-cm2/mg with 80 kΩ feedback resistors. © 1990 IEEE

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Plasma facing materials

Nuclear Fusion

Gauster, Wilhelm B.

The paper reviews the interaction of plasmas with materials and presents a status summary based on experience in large fusion experiments, laboratory investigations and design studies. The phenomena that are discussed limit the power densities and confinement properties attainable in plasmas; their control is an essential element of the design of future fusion devices. © 1990 IOP Publishing Ltd.

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Controlled microstructure oxide coatings for chemical sensors

Technical Digest, 1990 Solid-State Sensor and Actuator Workshop

Frye, G.C.; Brinker, C.J.; Ashley, C.S.; Martinez, S.L.; Bein, T.

The use of porous oxide coatings, formed using sol-gel chemistry routes, as the discriminating elements of acoustic wave (AW) chemical sensors, is investigated. These coatings provide several unique advantages: durability, high adsorption capacity based on large surface areas, and chemical selectivity based on both molecular size and chemical interactions. The porosity of these coatings is determined by performing nitrogen adsorption isotherms using the AW device response to monitor the uptake of nitrogen at 77 K. The chemical sensitivity and selectivity obtained with this class of coatings is demonstrated using several examples: hydrous titanate ion exchange coatings, zeolite/silicate microcomposite coatings, and surface modified silicate films.

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Volumetric light source theory

Walko, R.J.

In light sources such as tungsten filament bulbs, fluorescent tubes and gas tube type radioluminescent (RL) lamps, visible light is emitted from a thin surface layer of excited material. In contrast, neon bulbs, xenon flash tubes and lasers emit light generated throughout their volumes. The first group can be characterized as surface emitters and the latter as volumetric emitters. Theoretically, an ideal volumetric light source has definite advantages over a surface source. In reality, practical volumetric sources will have limitations as well. These advantages and limitations will be discussed with particular emphasis on comparisons between current gas tube type RL lamps and the more advanced volumetric RL lamps.

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Chemical Reactions During the Thermal Processing of Borazene Polymers

Journal of the American Ceramic Society

Rye, Robert R.

A class of borazene polymers was developed which consists of a two‐dimensional array of six‐membered borazene rings with the borons of adjacent borazene rings separated by ‐NH‐ groups. Pyrolysis of these polymers above ∼1000°C leads to crystalline graphite‐like boron nitride (h‐BN). The thermal chemistry of thin films of one polymer deposited on KOH‐eched aluminum was examined by thermal decomposition mass spectroscopy (TDMS) and thermal gravimetric analysis (TGA), and the gas evolution chemistry was found to be essentially complete at temperatures less than 400°C. All products desorb with the same temperature profile and the major desorbing species are NH3 and N2, consistent with a loss of excess nitrogen and hydrogen in the polymer, and HCl from decomposition of byproducts of the synthesis step. Since the formation of ordered crystalline h‐BN films requires heating to temperatures of the order of 1000°C, whereas the gas evolution chemistry is complete by roughly 400°C, it is concluded that gas evolution chemical processes are not rate limiting in BN ceramic production. Copyright © 1990, Wiley Blackwell. All rights reserved

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Radiation hardening of a high voltage IC technology (BCDMOS)

IEEE Transactions on Nuclear Science

Desko Jr., J.C.; Darwish, M.N.; Dolly, M.C.; Goodwin, C.A.; Dawes Jr., W.R.; Titus, J.L.

A program was undertaken to radiation harden AT&T's existing power integrated circuit technology (BCDMOS) to total dose, gamma dot, SEU, and neutrons. Efforts have centered around hardening and optimizing our CMOS, DMOS, and NPN devices. Initial results indicate a substantial improvement in hardness over our existing commercial technology. © 1990 IEEE

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Application of blast modeling to oil shale recovery

Hommert, Paul J.

The objective of this work is the development of numerical models of rock fragmentation by blasting that can be applied to oil shale recovery. Specifically, these models should be used to improve mining efficiency, evaluate alternative mining strategies and provide a basis for evaluating the blast design for in situ retort construction. 11 refs., 7 figs.

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Sedimentation of particles through quiescent suspensions

Mondy, L.A.

Studies of falling-ball rheometry in concentrated suspensions, embodying a combination of analysis experiment, and numerical simulation, are discussed. Experiments involve tracking small balls falling slowly through otherwise quiescent suspensions of neutrally buoyant particles. A theory has been developed relating the average ball velocity to the macroscopic suspension viscosity, and, for dilute suspensions, agreement is obtained with Einstein's sheared suspension viscosity. Detailed trajectories of the balls, obtained either with new experimental techniques or by numerical simulation, are statistically interpreted in terms of the mean settling velocity and the dispersion about that mean. We show that falling-ball rheometry, using small balls relative to the suspended particles, can be a means of measuring the macroscopic zero-shear viscosity without disturbing the original microstructure significantly; therefore, falling-ball rheometry can be a powerful tool to study the effects of microstructure on the macroscopic properties of suspensions. 25 refs.

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Joining engineering ceramics

Loehman, Ronald E.

Joining ceramics to metals requires solutions to both scientific and practical engineering problems. Scientific issues include understanding the fundamental nature of adhesion at metal-ceramic interfaces, predicting interfacial reactions, and understanding the relation between chemical bonding and mechanical stresses at the interface on the atomic level. Engineering a specific ceramic-metal joint requires finding the optimum among what may be inherently incompatible properties. The following review briefly outlines some of the different methods for joining ceramics. Following that, some fundamental aspects of ceramic joining are presented. The paper concludes with examples of ceramic bonding in several engineering ceramic systems.

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An examination of the 1-MeV equivalent silicon damage methodology

Griffin, P.J.; Kelly, J.G.; Luera, T.F.; Lazo, M.S.

The assumptions, approximations, and uncertainty in the 1-MeV equivalent silicon damage methodology are reviewed. A new silicon displacement kerma function, based on ENDF/B-VI cross sections, is presented and its shape is experimentally confirmed. The issue of an associated 1-MeV equivalent reference kerma value is discussed. 19 refs., 4 figs.

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Compatibility of Au base thick films with solder alloys: Solid state growth of intermetallics

Stephens, J.J.; Romig Jr., A.D.

Long term reliability of solder joints in thick film Au hybrid microcircuits require either minimization of the solid state growth of intermetallics or verification that if present, they do not compromise component performance. Intermetallic compounds such as AuIn{sub 2} or AuSn{sub 4} arise from the solid state reaction between Au thick films and 50Pb--50In or 63Sn--37Pb solder alloys, respectively; they are undesirable due to their brittle mechanical behavior caused by lack of a sufficient number of independent slip systems for plastic deformation. In addition, they may alter the resistivity of a circuit and thereby alter electronic performance. This paper will present a brief overview of the Au thick film inks/solder alloy systems whose intermetallic growth kinetics have been characterized at SNL, Albuquerque for hybrid microcircuit electronic applications. 6 refs., 3 figs., 2 tabs.

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Wear mechanisms of amorphous carbon and zirconia coatings on rigid disk magnetic recording media

Dugger, Michael T.

Examination of the durability of zirconia-coated rigid disks in various environments reveals a sensitivity to the presence of water vapor during sliding. Vacuum and dry air yield contact durabilities of 300 to 400 m, while in 50% relative humidity air the contact life increases to about 20 km. The durability of amorphous carbon-coated disks was also found to be more sensitive to the presence of moisture than to oxygen. The dominant factors affecting wear are believed to be oxidation of metallic debris and interaction of the overcoat layer with water vapor. Tests with ferrite read/write sliders on carbon-coated disks suggest that the pin-on-disc test is a valid simulation of the tribological behavior of this system. Carbon film thickness measurements indicate that the carbon film remains intact without appreciable thinning until the point of failure. 25 refs., 12 figs., 1 tab.

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Spline function smoothing and differentiation of noisy data on a rectangular grid

Dohrmann, Clark R.

A method is presented for smoothing and differentiating noisy data given on a rectangular grid. The method makes use of a one-dimensional smoothing algorithm to construct the solution to an associated two-dimensional problem. Smoothing parameter selection is automated using a technique that does not require prior knowledge of the amount of noise in the data. Numerical examples are provided demonstrating the application of the method. 4 refs., 8 figs., 2 tabs.

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Basic data report for drillhole H-12 (Waste Isolation Pilot Plant-WIPP)

Mercer, J.W.; Snyder, R.P.

Drillhole H-12 was drilled where hydraulic data were needed to better establish flow characteristics existing south-southeast of the WIPP site. The fluid-bearing zones of interest are the Magenta and Culebra dolomite units of the Rustler Formation. Dissolution of halite in the Rustler Formation has occurred in the uppermost member, but has not yet begun in the lower halite-bearing members. Cuttings and cores were taken at selected intervals and geophysical logs were run over the entire depth of the hole. 3 refs., 2 figs., 3 tabs.

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The synthesis of solar radiation data for sizing stand-alone photovoltaic systems

Chapman, R.N.

Research has shown that long-term hourly insolation data are necessary to properly size stand-alone photovoltaic systems. Even if these data are available, their direct use requires extensive computing capabilities and is not practical on a routine basis. This paper describes a three-step model that generates realistic long-term hourly insolations from average monthly insolations. The model executes rapidly on a personal computer and generates the hourly data needed to properly size stand-alone systems. The approach used to develop this model was unique in that system performance predictions rather than statistical properties were used to verify that the synthetic data were representative of actual data. Results of verification tests show that array sizes resulting from the synthetic data are within 6% of the array sizes resulting from actual hourly data for any system with at least two days of energy storage. 5 figs., 4 tabs.

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Performance testing and qualification of Sandia's third baseline photovoltaic concentrator module

Richards, Elizabeth H.

Sandia designed, built, and tested prototypes of a new photovoltaic concentrator module, the Sandia Baseline Module 3 (SBM3). The SBM3 is intended to be a high-efficiency module that can be readily adapted for commercial production. It consists of a 2 by 12 parquet of lenses arranged with 24 cells in an aluminum housing. The geometric concentration ratio is 185. The cells were made at the University of New South Wales and employ prismatic covers designed by ENTECH. The module features a new concept in cell assemblies in that the cells are soldered directly to a copper heat spreader, eliminating the expensive ceramic wafer and heat sink that have been used in previous designs. Electrical isolation was accomplished by anodizing the electrophoretically coating the aluminum housing. Lessons learned during construction and testing of the SBM3 are presented, along with the outdoor performance characteristics of prototype modules and results from qualification testing. 7 refs., 11 figs.

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Sandia Sorption Data Management System, Version 2 (SSDMS II): User's manual

Siegel, Malcolm D.

The Sandia Sorption Data Management System (SSDMS II) stores and retrieves trace element sorption data. The data management system has potential applications in performance assessment studies of transuranic high- and low-level, and toxic waste sites. The current version stores information describing the degree of sorption, the compositions of rocks and solutions used in the sorption experiment, and the experimental procedures. This User's Manual describes SSDMS II data searches, creation of new data files, and the merging of new with existing data base files. These extended data bases can be used to examine relationships among experimental variables, mineralogy of the substrate, water composition, and sorption ratios. Examples of using SSDMS II with a data base of radionuclide sorption data are given. 3 figs., 13 tabs.

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StateGEN/StateNET and DOT guidelines: Tools for highway routing of hazardous materials

Cashwell, J.W.

Under the sponsorship of the US Department of Energy Office of Defense Programs, Sandia National Laboratories' Transportation Technology Center has developed computerized software to assist state and local governments in determining highway routing alternatives for radioactive materials. The techniques have a still wider application in analyzing route alternatives for all hazardous materials transport activities. The specific techniques discussed in this presentation are the latest update of the StateGEN/StateNET model structure and routing algorithm which contains the codified US Department of Transportation (DOT) Guidelines for Highway Route Controlled Quantity shipments of radioactive materials. 6 refs.

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Results 96176–96200 of 96,771
Results 96176–96200 of 96,771