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Measured data for the Sandia 34-meter vertical axis wind turbine

Ashwill, T.D.

The 34-meter Test Bed is a research-oriented, variable-speed vertical-axis wind turbine located at the USDA Agricultural Research Station in Bushland, Texas. Sandia National Laboratories designed and built this machine to perform research in structural dynamics, aerodynamics, and fatigue. Testing to determine its performance in various wind conditions and rotation rates has been ongoing for over three years. This report documents a broad range of test data and includes comparisons to analytical results.

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Anisotropy of the Topopah Spring Member Tuff

Price, Ronald H.

Mechanical properties of the tuffaceous rocks within Yucca Mountain are needed for near and far-field modeling of the potential nuclear waste repository. If the mechanical properties are significantly anisotropic (i.e., direction-dependent), a more complex model is required. Relevant data from tuffs tested in earlier studies indicate that elastic and strength properties are anisotropic. This scoping study confirms the elastic anisotropy and concludes some tuffs are transversely isotropic. An approach for sampling and testing the rock to determine the magnitude of the anisotropy is proposed.

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TSPA 1991: An initial total-system performance assessment for Yucca Mountain; Yucca Mountain Site Characterization Project

Barnard, R.

This report describes an assessment of the long-term performance of a repository system that contains deeply buried highly radioactive waste; the system is assumed to be located at the potential site at Yucca Mountain, Nevada. The study includes an identification of features, events, and processes that might affect the potential repository, a construction of scenarios based on this identification, a selection of models describing these scenarios (including abstraction of appropriate models from detailed models), a selection of probability distributions for the parameters in the models, a stochastic calculation of radionuclide releases for the scenarios, and a derivation of complementary cumulative distribution functions (CCDFs) for the releases. Releases and CCDFs are calculated for four categories of scenarios: aqueous flow (modeling primarily the existing conditions at the site, with allowances for climate change), gaseous flow, basaltic igneous activity, and human intrusion. The study shows that models of complex processes can be abstracted into more simplified representations that preserve the understanding of the processes and produce results consistent with those of more complex models.

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Waste to fuels

Jackson, Nancy B.

This report discusses methods for making synthetic fuels from various kinds of wastes. Basic chemistry of synthesis gas creation and conversion is covered. Potentially productive wastes discussed are landfill natural gas, agricultural wastes, municipal wastes, industrial wastes, biomass, and tires. (VC)

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Mirror alignment techniques for point-focus solar concentrators

Diver, R.B.

Accurate alignment and focus of mirror facets are critical for the integration of concentrators and receivers in many of the low-cost stretched-membrane concentrators currently under development. In this report, the theoretical development of computer software that traces light rays from a source to a facet of a point-focusing solar concentrator and then to a target is given. Examples of approaches for the alignment of faceted point-focusing solar concentrators, which make use of targets generated by this computer program, are also presented.

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Institutional plan, FY 1992--1997

Dale, Bruce C.

This review of ongoing research at Sandia National Laboratory in the areas of nuclear weapons development and testing, arms control. As a multiprogram laboratory, their core competencies make special contributions in other areas of national importance. Work on US DOE programs is presented on the following subjects: robots; computers: arms control; nuclear weapons reliability; fusion research; solar energy; semiconductor detectors; radioactive waste management; nuclear explosion detection; and others. The laboratories strategic plan and other management methods are outlined. (GHH)

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Sodium reflux pool-boiler solar receiver on-sun test results

Andraka, Charles E.

The efficient operation of a Stirling engine requires the application of a high heat flux to the relatively small area occupied by the heater head tubes. Previous attempts to couple solar energy to Stirling engines generally involved directly illuminating the heater head tubes with concentrated sunlight. In this study, operation of a 75-kW{sub t} sodium reflux pool-boiler solar receiver has been demonstrated and its performance characterized on Sandia's nominal 75-kW{sub t} parabolic-dish concentrator, using a cold-water gas-gap calorimeter to simulate Stirling engine operation. The pool boiler (and more generally liquid-metal reflux receivers) supplies heat to the engine in the form of latent heat released from condensation of the metal vapor on the heater head tubes. The advantages of the pool boiler include uniform tube temperature, leading to longer life and higher temperature available to the engine, and decoupling of the design of the solar absorber from the engine heater head. The two-phase system allows high input thermal flux, reducing the receiver size and losses, therefore improving system efficiency. The receiver thermal efficiency was about 90% when operated at full power and 800{degree}C. Stable sodium boiling was promoted by the addition of 35 equally spaced artificial cavities in the wetted absorber surface. High incipient boiling superheats following cloud transients were suppressed passively by the addition of small amounts of xenon gas to the receiver volume. Stable boiling without excessive incipient boiling superheats was observed under all operating conditions. The receiver developed a leak during performance evaluation, terminating the testing after accumulating about 50 hours on sun. The receiver design is reported here along with test results including transient operations, steady-state performance evaluation, operation at various temperatures, infrared thermography, x-ray studies of the boiling behavior, and a postmortem analysis.

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Real-time data compression using a FFT digital signal processor

Brady, E.

This report describes a hardware implementation of a fast fourier transform (FFT) based real time data compression system. The system is currently configured to compress and analyze airborne vehicle vibration data but it can be utilized for compressing any one- dimensional data stream. The algorithm uses a two-stage process to compress successive stationary time periods of input data. The first stage compresses data by transforming continuous blocks of 2048 points to the frequency domain using Welch's method. The second stage provides further compression by logarithmically averaging adjacent frequency bins of the transformed signal. These compression techniques result in a bandwidth savings from 8:1 to 64:1 per channel compared to strictly analog or digital transmission techniques. The complete technique as well as the hardware used to implement it is described in detail in this report.

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Controlled atmosphere soldering system

Keicher, D.M.; Hernandez, C.L.; Frear, D.R.; Hosking, F.M.

We have developed a controlled environment system in which to perform wetting experiments to analyze the effects of various atmospheres, both inert and reducing, on solder processing. This system consists of a custom designed vacuum chamber, an apparatus for heating specimens and a video system for data acquisition. The system design allows for rapid changes to various processing atmospheres. Specimens can be heated to soldering temperature from room temperature rapidly. The temperature is regulated by a controller which gives a maximum heating rate of 23{degrees}C/second while minimizing the amount of overshoot, thereby quickly a stabilized temperature. A video system is used to acquire the data in the form of both numerical data and real-time video images. The video system allows multiple views of the wetting process to be captured and simultaneously records time and temperature information. The recorded information is suitable for digital analysis. The controlled atmosphere soldering system has been used to perform experiments that examine the effect of inert and acid vapor atmospheres on solder wetting behavior.

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A distributed visualization environment for engineering sciences

Pavlakos, Constantine

As a multiprogram engineering laboratory, Sandia National Laboratories (SNL) has major research and development responsibilities for nuclear weapons, arms control, energy, environment, and other areas of strategic importance to national security. To accomplish this diversified mission, analysts within the Engineering Sciences Directorate support the entire laboratory using finite element and finite difference solution schemes to solve problems in fluid dynamics (steady state and transient, compressible and incompressible), thermodynamics (heat transfer), hydrodynamics (impact physics, penetration mechanics), solid mechanics (structural/thermal analysis, fracture mechanics, ground subsidence, impact modeling) and structural dynamics. To assist these analysts in performing these analyses most efficiently, the Applied Visualization Group was formed and tasked to develop a ``production scientific visualization environment.`` In this paper, we characterize a visualization environment that has been designed and prototyped for a large community of scientists and engineers. The proposed environment makes use of a visualization server concept to provide effective, interactive visualization to the user`s desktop. Benefits of using the visualization server approach are discussed. Some thoughts regarding desirable features for visualization server hardware architectures are also addressed. A brief discussion of the software environment is included. The paper concludes by summarizing certain observations which we have made regarding the implementation of such visualization environments.

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Bridged polysilsesquioxanes: A novel class of hybrid organic-inorganic materials

Loy, Douglas A.

Aryl-, ethynyl- and alkyl-bridged polysilsesquioxanes were prepared by the hydrolysis and condensation of the respective bridged triethoxysilanes under both acidic and basic conditions. Gelation of the resulting sols can take place at concentrations as low as 0.02 M in tetrahydrofuran. The gels can be air dried to afford xerogels or extracted with supercritical carbon dioxide to give high surface area aerogels. The materials were characterized by solid state {sup 13}C and {sup 29}Si CP MAS NMR spectroscopies, gas sorption porosimetry, and thermal gravimetric analysis. The bridged polysilsesquioxanes offer the opportunity to prepare hybrid organic-inorganic materials with properties unique from other siloxane network materials and silica gels.

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A miniaturized sensor system for in situ robotic characterization of hazardous waste

Feddema, John T.

This paper describes current research and development on miniaturized sensing systems for use during in situ characterization of nuclear waste storage tanks, buried waste sites, and decommissioned production facilities. Each miniaturized sensor system will consist of a suite of chemical, radiological, and physical properties sensors integrated into a compact package which will be mounted on the end of a robotic arm and/or vehicle. While the specific size of this remote sensor head and the types of sensors included will depend on site needs, the supporting generic computing system may be used for other waste characterization applications. This computing system will contain all necessary hardware and software to acquire, combine, interpret, display, and archive a wide range of sensor data. This paper describes the present status of the project, the lessons learned from the first prototype, and planned future designs of the next generation system. 7 refs.

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International technology transfer to support the environmental restoration needs of the DOE complex

Ducharme, A.R.; Jimenez, R.D.; Roberds, W.J.

One of the principal objectives of the International Technology Exchange Program (ITEP) is the exchange of waste management and environmental restoration (WM/ER) technologies between the US and other nations. The current emphasis of ITEP is the transfer of technologies to the US that could provide better, faster, cheaper, or safer solutions to the needs of the DOE complex. The 10 candidate technologies that have been identified thus far by ITEP are discussed. The highlights of preliminary evaluations of these technologies through a systems approach are also described. The technologies have been evaluated by a screening process to determine their applicability to the leading WM/ER needs of the DOE complex. The technologies have been qualitatively compared with the known or anticipated capabilities of domestic, base case technologies.

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Investigations of deteriorated concrete from the liner of the Waste Isolation Pilot Plant Waste Shaft

Nowak, E.J.

During inspections of the Waste Isolation Pilot Plant Waste Shaft in May 1990, patchy areas of apparently degraded concrete were observed on the inner surface of the shaft liner between approximately 810 feet and 900 feet below the surface. The apparent cause of this degradation is chemical reaction of the concrete with magnesium-bearing brine in the annulus between the concrete liner and the host rock. The greater thickness of the degraded layer below the joint may be related to the different chemical compositions that were determined by analyses of the paste portions of concrete samples from above and below the joint. The analytical results support a complex mechanistic explanation of concrete degradation observed behind the liner and in the joint: chemical weakening of the concrete paste; cracking by precipitation of solids in pores; and increased permeability due to calcium chloroaluminate formation. Additional sampling, analyses, and regular monitoring are worth considering to bound the vertical extent of Waste Shaft liner degradation, detect concrete liner degradation in other shafts, and measure any ongoing degradation that may be occurring.

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Numerical computation of the lightning response of an earth-covered munitions storage bunker and comparison with experiments

Merewether, Kimball O.

This paper presents recent progress in using finite-difference analysis codes to simulate the responses of complex structures due to direct lightning. Significant advances have been made in interfacing a finite-difference code with commercial computer aided design tools, in suppressing a pervasive instability associated with the thin-wire algorithm for modeling conductors much smaller than a cell size, and in visualizing the results with color movies. Preliminary comparisons between the results of the finite-difference code and the results obtained during a recent rocket-triggered lightning test are also presented. 3 refs.

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The influence of damping on computer simulations of rock motion

Preece, D.S.

Computer modeling of the blasting process can aid in gaining an understanding of the physics controlling the process. The sequence of events in a blast occur so rapidly and in such a violent environment that measurements are still difficult to obtain. Computer modeling using a program such as DMC [Taylor and Preece, 1989a, 1989b] can provide insights into the physics of the rapid and violent events associated with a blast. DMC has been used to simulate crater blasting [Preece, 1990c] and the blasting of Oil Shale for modified in-situ retorting [Preece, 1990a, 1990b]. This paper will address the influence that damping has on the velocity distribution in the rock mass during the rock motion phase of a blast. Since velocity distribution is a controlling factor of muck pile shape, damping also contributes to muck pile shape.

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The RADLAC beam propagation experiment

Frost, C.A.; Shope, S.L.; Mazarakis, M.G.; Poukey, J.W.; Wagner, J.S.; Turman, B.N.; Crist, C.E.; Welch, D.R.; Struve, K.W.

The most recent RADLAC experiments studied propagation and hose stability of a high current beam propagating in the atmosphere, and confirmed the convective nature of the hose instability. The unique combination of high beam current and extremely small initial perturbation, allowed saturation of the hose instability to be observed for the first time. Data on high current propagation was needed because the current scaling is more complex than energy scaling. It was important to collect data at atmospheric pressure to insure that subtle air chemistry effects such as avalanche did not distort the experiment. With this philosophy, the results should be directly scaleable to applications at higher energy.

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Toxicological effects of Kuwaiti oil fires

Engi, Dennis

The possibility of long-term smoke emissions (from 1 to 3 years) from burning Kuwaiti oil wells has increased concerns regarding personnel exposure and acute and chronic health effects. This document, which is the result of work done in the spring of 1991, addresses those concerns. Part 1 of this document describes follow-on efforts to the pre-war modeling studies of the toxicological hazards to exposed Kuwaiti populations. Part 2 describes a pollutant monitoring program that could be carried out in the summer of 1991 to measure real-time exposure levels and to obtain more detailed information about the pollutant source terms and meteorological conditions that are necessary inputs to model computations.

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Fractures and stresses in Bone Spring sandstones. Final report

Northrop, D.A.

This project was a collaboration between Sandia National Laboratories and the Harvey E. Yates Company (Heyco), Roswell, NM, conducted under the auspices of Department of Energy`s Oil Recovery Technology Partnership. The project applied Sandia perspectives on the effects of natural fractures, stress, and sedimentology for the stimulation and production of low permeability gas reservoirs to low permeability oil reservoirs, such as those typified by the Bone Spring sandstones of the Delaware Basin, southeast New Mexico. This report details the results and analyses obtained in 1990 from core, logs, stress, and other data taken from three additional development wells. An overall summary gives results from all five wells studied in this project in 1989--1990. Most of the results presented are believed to be new information for the Bone Spring sandstones.

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Design procedure and characterization for V-band stepped ridge waveguide-to-microstrip transition

Slayton III, E.M.

Waveguide-to-microstrip transitions are extremely important components of mm-wave communication systems because it is the interface between the signal processing circuitry and the transmitted/received signal. This report describes the design procedure, construction detail, and measurement of both 3 and 4 step stepped ridge waveguide (RWG) transitions. Both transitions had > 10 dB return loss over the frequency band of interest (57--63 GHz) while insertion loss was less than 1 dB. Also, the transition lengths were at least half as long as traditional finline transitions while having superior performance. These shorter lengths were achieved by violating the ``small-step`` assumption usually used in RWG transition design. 7 refs.

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Development and evaluation of a meter for measuring return line fluid flow rates during drilling

Loeppke, G.E.; Schafer, D.M.; Glowka, D.A.; Scott, D.D.; Wernig, M.D.; Wright, E.K.

The most costly problem routinely encountered in geothermal drilling is lost circulation, which occurs when drilling fluid is lost to the formation rather than circulating back to the surface. The successful and economical treatment of lost circulation requires the accurate measurement of drilling fluid flow rate both into and out of the well. This report documents the development of a meter for measuring drilling fluid outflow rates in the return line of a drilling rig. The meter employs a rolling counterbalanced float that rides on the surface of the fluid in the return line. The angle of the float pivot arm is sensed with a pendulum potentiometer, and the height of the float is calculated from this measurement. The float height is closely related to the fluid height and, therefore, the flow rate in the line. The prototype rolling float meter was extensively tested under laboratory conditions in the Wellbore Hydraulics Flow Facility; results from these tests were used in the design of the field prototype rolling float meter. The field prototype meter was tested under actual drilling conditions in August and September 1991 at the Long Valley Exploratory Well near Mammoth Lakes, Ca. In addition, the performance of several other commercially available inflow and outflow meters was evaluated in the field. The tested inflow meters included conventional pump stroke counters, rotary pump speed counters, magnetic flowmeters, and an ultrasonic Doppler flowmeter. On the return flow line, a standard paddlemeter, an acoustic level meter, and the prototype rolling float meter were evaluated for measuring drilling fluid outflow rates.

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Open Skies Treaty imaging radar technology issues

Sandoval, M.B.

This paper discusses the imaging radar technology requirements for the Open Skies regime including the unresolved issues to be discussed at future Open Skies Consultative Commission (OSCC) meetings. Compliance with international rules on shared technology is addressed and some of the practical considerations for operational deployment of the radar imaging equipment in an Open Skies aircraft are presented. The Open Skies Treaty requirements and validation methodologies for imaging radars that have been agreed on and those that will require future OSCC review are discussed.

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Supercritical carbon dioxide extraction of gel-derived polymer foams

Russick, Edward M.

Supercritical fluid technology has been used in industry for the extraction and separation of materials in a number of applications such as food preparation and petroleum processing. Gel-derived microcellular polymer foam technology, developed at Sandia, requires the extraction of organic solvents from thermally-induced phase separated gels to yield microcellular foams. We have applied supercritical fluid extraction technology to these specialized materials by using supercritical carbon dioxide to extract a variety of organic solvents from gels to produce foams. Our supercritical extraction process will be described, as well as high pressure equipment that is used to perform the extractions. The results of gel extraction trails and qualitative supercritical carbon dioxide/solvent miscibility experiments will also be presented. We plan to pursue other related areas in this field, including supercritical fluid cleaning, quantitative solubility studies, and supercritical fluid chromatography.

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Integrated Management Requirements mapping

Holmes, J.T.; Andrews, N.S.

This document contains five appendices documenting how Sandia implemented the DOE Conduct of Operations (5480.19) and DOE Quality Assurance (5700.6C) orders. It provides a mapping of the Sandia integrated requirements to the specific requirements of each Order and a mapping to Sandia`s approved program for implementing the Conduct of Operations Order.

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Heuristic sampling on DAGs

Chen, Pang-Chieh

Many problems in computer applications can in theory be solved by searching through a directed-acyclic graph (DAG). In practice, however, this approach has been hampered by our analytical inability to predict the search cost accurately without actually implementing and executing the program. To overcome this inability, a simple and quick heuristic procedure based on a stratified sampling approach is presented. In generalizes a tree sampling technique already shown to be useful in predicting the performance of tree-searching programs. With the addition of this DAG sampling procedure, we should be able to forecast the complexity and feasibility of alternative tree or DAG searching algorithms so that we may utilize our computational resources more effectively.

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Conduct of Operations and Quality Assurance Compliance

Andrews, N.S.

The purpose of this document is to present and detail the deliverables for the Tiger Team Action Plan, Finding MF-11, and milestones in the FY92 Performance Appraisal for Conduct of Operations from Sandia National Laboratories to DOE. The ``Proposal for Reporting Conduct of Operations & Quality Assurance Compliance to DOE`` describes what the deliverables shall be. Five major steps that result in the development of line practices are covered in this document. These line practices specify what Sandia will do to comply with the above DOE management orders. The five steps include: hazard classification; programmatic risk classification; management grouping; compliance plan; and corporate reporting.

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Automatic Attenuation/Phase Calibration System (AAPCS)

Still, C.J.

An automatic attenuation/phase calibration system which simultaneously certifies attenuation and transmission angle through up to 100 dB of loss has been developed at Sandia National Laboratories. System hardware is commercially available while the software and the certification techniques constitute the development effort. The system is computer controlled and intended primarily for standards type measurements. 14 refs.

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Evaluation tests for photovoltaic concentrator receiver sections and modules

Woodworth, Joseph R.

Sandia has developed a third-generation set of specifications for performance and reliability testing of photovoltaic concentrator modules. Several new requirements have been defined. The primary purpose of the tests is to screen new concentrator designs and new production runs for susceptibility to known failure mechanisms. Ultraviolet radiation testing of materials precedes receiver section and module performance and environmental tests. The specifications include the purpose, procedure, and requirements for each test. Recommendations for future improvements are presented.

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Gas blowthrough and flow quality correlations for use in the analysis of high pressure melt ejection (HPME) events

Pilch, M.; Griffith, R.O.

A number of correlations describing the advent of gas blowthrough and the subsequent exit quality were collected and examined. A simple scaling analysis was applied to these correlations to identify important nondimensional groups, and the range of values for these dimensionless groups at nuclear power plant (NPP) and experimental scales were used to examine the applicability of the correlations at different scales. The performance of each of the correlations was also assessed over a typical parameter range for NPP and experimental conditions. The Gluck correlations for the onset of gas blowthrough is recommended for high pressure melt ejection analyses. AL new model is developed for predicting the two-phase flow quality following the onset of gas blowthrough. Uncertainty estimates for the blowthrough correlation and the flow quality correlation are quantified.

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Part 1, Use of seismic experience and test data to show ruggedness of equipment in nuclear power plants; Part 2, Review procedure to assess seismic ruggedness of cantilever bracket cable tray supports

Kennedy, R.P.; Von Riesemann, W.A.; Wyllie Jr., L.A.; Schiff, A.J.; Ibanez, P.

In December 1980, the US Nuclear Regulatory Commission (NRC) designated ``Seismic Qualification of Equipment in Operating Plants`` as an Unresolved Safety Issue (USI), A-46. The objective of USI A-46 is to develop alternative seismic qualification methods and acceptance criteria that can be used to assess the capability of mechanical and electrical equipment in operating nuclear power plants to perform the intended safety functions. A group of affected utilities formed the Seismic Qualification Utility Group (SQUG) to work with the NRC in developing a program methodology to enable resolution of the A-46 issue. To assist in developing a program methodology, SQUG and the NRC jointly selected and supported a five-member Senior Seismic Review and Advisory Panel (SSRAP) in June 1983 to make an independent assessment of whether certain classes of equipment in operating nuclear power plants in the United States have demonstrated sufficient ruggedness in past earthquakes so as to render an explicit seismic qualification unnecessary. SSRAP operated as an independent review body with all of its findings submitted concurrently to both SQUG and the NRC. During their period of involvement, SSRAP issued several draft reports on their conclusions. This document contains the final versions of these reports; namely, ``Use of Seismic Experience and Test Data to Show Ruggedness of Equipment in Nuclear Power Plants,`` dated February 1991 and ``Review Procedure to Assess Seismic Ruggedness of Cantilever Bracket Cable Tray Supports,`` dated March 1, 1991.

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Simulation of the dynamic behaviour of polymeric gels

Proceedings of SPIE - The International Society for Optical Engineering

Witkowski, Walter

This paper presents a theoretical model to predict the curvature of a rectangular gel which is subjected to a pH gradient. The curvature is formulated as a function of volumetric strains. Experimental observations indicate a direct coupling between the electric field and the gel that induces an immediate volume collapse independent of pH gradients. Additional deformations occur later due to a pH gradient evolving through hydrolysis.

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Growth and optical characterization of Zn{sub 1-x}Mn{sub x}Te grown by molecular beam epitaxy

Reno, John L.

We have grown Zn{sub 1-x}Mn{sub x}Te alloys by molecular beam epitaxy and characterized them using x-ray diffraction and low temperature magnetoluminescence. Zn{sub 1-x}Mn{sub x}Te is a dilute magnetic semiconductor (DMS) whose bandgap ranges from the green through the blue part of the spectrum and is therefore of interest for blue LEDs.

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An ion movie camera for particle-beam-fusion experiments

Stygar, William A.

A camera with 3-ns time resolution -- and a continuous (> 100-ns) record length -- has been developed to image a 10{sup 12}-10{sup 13} W/cm{sup 2} ion beam for inertial-confinement-fusion experiments. A thin gold Rutherford-scattering foil placed in the path of the beam scatters ions into the camera. The foil is in a near-optimized scattering geometry and reduces the beam intensity seven orders of magnitude. The scattered ions are pinhole imaged onto a 2-D array of 39 p-i-n diode detectors. The output of each detector is recorded on a LeCroy 6880 transient-waveform digitizer. The waveforms are analyzed and combined to produce a 39-pixel movie which can be displayed on an image processor to provide, for example, time-resolved horizontal- and vertical-focusing information.

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Survivable debris shields for laboratory soft x-ray simulation sources

Spielman, Rick

A survivable debris shield is necessary if very high levels of cleanliness are to be achieved on samples exposed to soft x rays from laboratory simulation sources. These samples, often of optical quality, require a low or zero debris environment in order to distinguish low levels of soft x-ray damage from debris-induced effects. We will describe the development of survivable debris shield technology on the Sandia National Laboratories` Saturn x-ray simulation facility, which permits ultraclean exposure over sample areas of 58 cm{sup 2} {at} {approximately}0.35 cal/cm{sup 2}, 5 cm{sup 2}{at} {approximately}0.8 cal/cm{sup 2}, cm{sup 2}, 2.8 cm{sup 2} {at} {approximately}1.2 cal/cm{sup 2}, and 0.8 cm{sup 2} {at} {approximately}1.5 cal/cm{sup 2} with 3-keV argon K-shell photons. These new fluence-area produce test capabilities represent an order-of-magnitude improvement in the state of the art (previously 0.25 cm{sup 2} {at} {approximately} 1 cal/cm{sup 2} or 1.0 cm{sup 2} {at} {approximately}0.35 cal/cm{sup 2}) for soft x-ray simulators.

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A comparison of interstital oxygen calculated by different techniques

Medernach, J.W.

Methods which report an ability to determine interstitial oxygen (O{sub i}) in heavily doped silicon include the short baseline (SBL) and the curved baseline (CBL) techniques. Both the SBL and CBL methods are similar with the exception of the calibration. We developed a FORTRAN software package to provide separate methods for calculating O{sub i}. The strength of the software is its ability to rapidly compare methods. We report on a comparison of calculation methods including the ASTM standard test F1188-88 which is used in a calibration, and the SBL and the CBL methods, which are used for the heavily doped silicon to provide reliable results. The O{sub i} values calculated for both virgin and thermally processed silicon are reported.

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Strategies for change within Sandia National Laboratories

Burcham, William R.

This paper identifies some of the sources of resistance to change that face Sandia National Laboratories` management, and examines the mechanisms that are being used to minimize the effects of that resistance. The rapid and radical nature of many of the changes now being demanded of Sandia make them all the more likely to meet stiff resistance from within the organization. Sandia`s management has attempted to anticipate some of the sources of resistance to the changes planned for its operating procedures and has taken action to minimize their effects. Within this paper, particular attention is given to those individuals who will not only be most effected by, by may also be required to implement the changes. The change process at Sandia is currently ongoing. It is not complete. No claim is made that all of the changes that will be necessary at Sandia National Laboratories have been recognized, nor that all sources of resistance have been anticipated.

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Metal vapor plasma behavior during vacuum arc remelting of alloy 718

Zanner, F.J.; Maguire, M.C.; Williamson, R.L.; Adasczik, C.B.; Roberts, R.R.; Strohecker, R.

A production vacuum arc remelt (VAR) furnace was modified to enable direct viewing of the metal vapor arc and molten electrode tip during melting of 432 mm dia. alloy 718 electrodes into 508 mm dia. ingots. Diffuse and constricted arcing conditions were characterized using high speed cinematography, standard video format, and monochromatic imaging. Constricted arcing was observed while melting electrodes contaminated with oxide slag of the type used for refractory linings in vacuum induction furnaces. Monochromatic imaging was used in visualize the ion distribution in the arc plasma; these images clearly showed whether the arc operated in a diffuse or constricted model. Diffuse arc melting conditions were very similar to those previously reported in the literature for smaller laboratory sized melts.

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The technology-based regional economic development program at Sandia National Laboratories

Allen, Mark S.

In November of 1989, technology transfer became a mission for Sandia National Laboratories, (SNL), with the passage of the National Competitiveness Technology Transfer Act. In order to address the specialized technology transfer needs of small businesses, SNL created and implemented the Technology-Based Regional Economic Development (TRED) program. The TRED model has two major components -- technology assistance (or teaming), and `` widget transfer.`` In the technology assistance component, SNL`s technology resources (expertise, services, and equipment) are made available to companies developing commercial products. In the ``widget transfer`` component, SNL`s intellectual property (patents, copyrights) is placed with private sector firms through various partnership intermediaries

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Surface chemistry of MoS{sub 2} lubricant films: 1, Effects of high humidity storage on sputtered films

Peebles, Diane

Many MoS{sub 2} lubricant film formulations exhibit tribological performance degradation after extended storage in high humidity ambient environments. As a part of an extensive study of the effects of high humidity storage on a wide variety of MoS{sub 2} lubricant film formulations, the effects of high humidity storage on sputtered MoS{sub 2} films have been examined. The surface chemistries of a series of ten different commercially deposited MoS{sub 2} lubricant film formulations on 440C stainless steel have been examined before and after 1 month of storage at 98% relative humidity. While the films varied greatly in film chemistry prior to high humidity storage, many smaller differences were observed after high humidity storage. Addition of Ni to the films affects the film chemistry far more dramatically than the addition of AuPd or SbO{sub x}, facilitating oxidation of the MoS{sub 2} and enhancing formation of sulfate species. All of the films are adequately characterized by considering only MoS{sub 2} and MoO{sub 3} species, with the exception of the films co-sputtered with Ni and ion implanted with N{sup +}, where some MoO{sub 2} or MoS{sub 2-x}O{sub x} must also be present.

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A temperature dependent SPICE macro-model for power MOSFETs

Pierce, D.G.

A power MOSFET macro-model for use with the circuit simulator SPICE has been developed suitable for use over the temperature range of {minus}55 to 125{degrees}C. The model is comprised of a single parameter set with the temperature dependence accessed through the SPICE TEMP card. This report describes in detail the development of the model and the extraction algorithms used to obtain model parameters. The extraction algorithms are described in sufficient detail to allow for automated measurements which in turn allows for rapid and cost effective development of an accurate SPICE model for any power MOSFET. 22 refs.

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Fragment hazard zone analyses for explosive test facilities

Vigil, Manuel G.

The analytical procedures for establishing the fragment hazard zone for explosive test facilities are presented. Environment, safety and health regulations require that a hazard zone analysis be conducted for every explosive test facility. Analyses are presented for explosively driven missile fragment trajectories resultant from cased explosive configurations. Fragment trajectory parameter data are presented in graphical form for three different fragment materials (aluminum, steel and tantalum), initial velocities between 0.6mm/{mu}s (2000 ft/sec) to 4.3mm/{mu}s (14,000 ft/sec), and for various geometries. This trajectory information is used, as an example, to determine the safe distance or hazard zone for the Area 2 explosive test facility at Sandia National Laboratories.

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Scaling of IFR propagation physics with beam/channel parameters

Shokair, Isaac R.

The equations of motion of beam and channel particles are analyzed in the ion focused regime. Using the paraxial approximation and assuming only transverse electro-magnetostatic interactions between beam and channel particles for the equations of motion (the same equations solved in the BUCKSHOT code) are written in non-dimensional form and scaling relations are derived for propagation parameters, magnetic erosion, and evaporation. These relations are very useful in doing parameter studies with a limited number of computer simulations.

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Characterization of impact-limiting material

Duffey, T.A.; Glass, R.E.; Mcconnel, P.

Methods of mechanical and thermal testing specifically directed toward evaluation of impact-limiting materials for radioactive material transportation containers are presented. Associated figures of merit and procedures for rank-ordering the materials are also developed. Based on testing and evaluation procedures developed herein, thermal and mechanical results are presented for high- and low-density aluminum honeycombs, polyurethane foams, and aluminum foams. On a minimum mass basis, the high-density aluminum honeycomb is found to be a superior impact energy absorber up to the point of lock up. On a minimum volume basis, the high-density polyurethane foam is far superior, however. Based on the thermal figures of merit, the high-density polyurethane foam was found to be the most favorable material.

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Basic Impact Limiter Study

Uncapher, W.L.; May, R.A.; Miller, J.D.

The energy-absorbing capability of impact limiters is an important part of radioactive waste transportation system. This document presents the results of the Basic Impact Limiter Study (BILS). The objective of this design development program was to increase the energy-absorbing capabilities of an external impact limiter for both axial and off-axis response. The impact limiter that was evaluated was made of stainless steel and was a right circular cylinder. The evaluation included computer analysis complemented by static and dynamic testing of quater-scale and half-scale models. The design development, analysis, and testing were conducted at Sandia National Laboratories.

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Audit calculations with CORCON-MOD 3 of the duration of superheat in NUREG/CR-5423

Powers, Dana A.

Analyses have shown that early rupture of the Mark-I boiling water reactor containment-by the direct action of core debris depends strongly on the time that core debris is superheated above its liquidus. The analyses of the duration of superheat in the core debris are compared to predictions obtained with the CORCON-MOD 3 computer code. The predicitons of this computer code as functions of the core debris mass, composition, and initial superheat are used to create a polynomial response surface. This response surface is used in a Monte Carlo analysis to produce probability distributions for the duration of superheat in core debris in the drywell of a Mark-I containment. It is concluded that to a high level of confidence (>90%) the duration of superheating predicted with the CORCON-MOD 3 code is less than what has been used in the analyses of the threats to the Mark-I containment liner. Based on these results, to the extent superheat duration dictates the threat to the liner, analyses in NUREG/CR-5423 would appear to overestimate the threat to the liner in comparison to threats estimated using the predictions of the duration of superheating obtained with CORCON-MOD 3.

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Analysis of transporting highway route-controlled quantities: An overview of 1985--1990

Mcclure, J.D.

A postnotification record is required for all Highway Route Controlled Quantities of radioactive materials that are shipped in the United States. These reports, which are required by 49 CFR 172.203(d), are compiled in the Radioactive Materials Routing Report (RAMRT) database at the US Department of Transportation (DOT). Sandia National Laboratories` has developed an expanded version of the RAMRT which is entitled the Radioactive Materials Postnotification (RAMPOST) database. This paper provides the summary detail on the following topics: major carriers of highway route controlled quantities, major US Department of Energy (DOE) shippers, major US Nuclear Regulatory Commission (NRC) shippers and a breakdown of the types of Highway Route Controlled Quantities that have been shipped for the time period 1985--1990.

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The development of an optical fiber accelerometer

Casalnuovo, Stephen A.

We describe the design and operation of an optical fiber accelerometer intended for environments inhospitable to electronic components. An overview of the device is presented along with descriptions of the optical, electronic, and mechanical components. The performance of the current prototype is equivalent to state of the art piezoelectric accelerometers. Improvements to the current design are discussed.

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Results 97551–97600 of 99,299
Results 97551–97600 of 99,299