Publications

The effects of total-dose irradiation on PbO-ZrO{sub 2}-TiO{sub 2} ferroelectric capacitors have been studied in detail. It is shown that significant total-dose degradation of ferroelectrics can occur at dose levels greater than 1 Mrad(Si). 6 refs., 5 figs.

PIC's (Power Integrated Circuits) are becoming increasingly important because they allow integration of high-voltage and high-current power transistors, precision linear control circuitry, and low-voltage logic gates on the same monolithic chip. Integration of power and control functions provide benefits in reduced weight and size, enhanced reliability, and lower costs over conventional designs using these same components packaged separately. However, commercial PIC technologies, including AT T's commercial BCDMOS technology, are susceptible to failure in radiation environments. The relative lack of radiation hardness of the AT T BCDMOS technology was previously reported at this conference. Radiation hardening of PIC technologies is significantly more difficult than for other IC technologies, primarily because of the integration of many different types of devices into the technology. To facilitate integration, different devices share processing sequences. Thus, no one device can be optimized independently of the remaining devices. Since each device has its own distinct radiation response, this adds another set of constraints on the optimization of the overall technology from the point of view of device performance and radiation response. The high-voltage requirements further complicates efforts to harden a PIC technology. Modifying one device to optimize one aspect of its performance can severely impact all the other devices in the technology. 4 refs., 5 figs.

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.

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.

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.

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.

By recirculating a relativistic electron beam (REB) in phase with a repeating accelerating voltage, it is possible to construct compact, efficient, high voltage gradient, linear induction accelerators (LIA). Concerns about energy spreads due to degradation of our 1.1-MV, 34-ns duration accelerating activity repeating pulse shapes have resulted in our improving the 24-switch trigger system for the ET-2 cavity, and identifying critical factors in the cavity design that affect the pulse shape. We summarize the improvements (completed and proposed) for the existing ET-2 cavity pulsed power and the status of our design analysis and modelling for the new four-pass accelerating cavities that could produce a 20-MeV REB for RLA. 14 refs., 24 figs.

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.

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.

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.

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.

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.

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.

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.

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.

The 1/f noise of MOS transistors has been measured as a function of total ionizing dose and postirradiation biased annealing time. Comparison to oxide and interface trapped-charge buildup and annealing is discussed. 13 refs., 3 figs.

Significant improvements in CMOSIC quality, reliability, and fabrication yield can be readily achieved in the 1990s by appropriate implementation of tests for quiescent power supply current (I{sub DDQ}). As part of an overall quality management program, I{sub DDQ} testing incorporated with design for testability and modified conventional logic response testing enables 100% stuck-at fault coverage, quality improvement goals of defective levels less than 100 PPM, and reliability greater than 0.999 for 30 years. 9 refs., 2 figs., 1 tab.

Gravitational forces have been found to be an important factor in defining the particle collection efficiency curve of inertial impactors for large particles. In general it was found that if the parameter {cflx G} = gW/V{sub 0}{sup 2} (g is the gravitational acceleration, W is the nozzle diameter and V{sub 0} is the average fluid velocity at the nozzle throat) in greater than 10{sup {minus}3}, the efficiency curve would shift to lower particle sizes. No effect could be seen for lower values of {cflx G}. 1 ref., 1 fig., 1 tab.

X-ray microanalysis by analytical electron microscopy (AEM) has proven to be a powerful tool for characterizing the spatial distribution of solute elements in materials. True compositional variations over spatial scales smaller than the actual resolution for microanalysis can be determined if the measured composition profile is deconvoluted. Explicit deconvolutions of such data, via conventional techniques such as Fourier transforms, are not possible due to statistical noise in AEM microanalytical data. Hence, the method of choice is to accomplish the deconvolution via iterative convolutions. In this method, a function describing the assumed true composition profile, calculated by physically permissible thermodynamic and kinetic modeling is convoluted with the x-ray generation function and the result compared to the measured composition profile. If the measured and calculated profiles agree within experimental error, it is assumed that the true compositional profile has been determined. If the measured and calculated composition profiles are in disagreement, the assumptions in the physical model are adjusted and the convolution process repeated. To employ this procedure it is necessary to calculate the x-ray generation function explicitly. While a variety of procedures are available for calculating this function, the most accurate procedure is to use Monte Carlo modeling of electron scattering. 9 refs., 1 fig.

TNF-doped Mylar is a new radiation-hard dielectric that has recently been qualified as a viable substitute for Mylar in capacitors. The advantage of TNF-doped Mylar is that it satisfies both the nuclear safety and radiation hardness requirements of weapons. Mylar is not radiation-hard. Aging and compatibility studies were carried out to insure that (1) TNF does not diffuse from the film during fabrication of the capacitor or during storage; and (2) there are no compatibility problems with aluminum foil (the conductor) or Fluorinert (the secondary dielectric). Losses of TNF were barely detectable during the vacuum bakes used in fabricating capacitors or during accelerated aging tests carried out below T{sub g} (70C) over a two year period in air. In other accelerated tests, no compatibility problems were detected with aluminum or Fluorinert. TNF-doped Mylar is now being used in the MC-4109 capacitor that was called out for use in SRAM II. We anticipate no age-related or compatibility-related problems with TNF-doped Mylar.

The equilibrium swelling of a number of elastomeric seals, commonly used in weapon components, was determined after they were exposed to a saturated solvent environment. The dimensional stability of these elastomers in the solvents varied considerably. Reasons for this are discussed and a method by which one may estimate the degree of swelling that these elastomers will undergo in a solvent environment is presented. 5 refs.

This paper surveys a few of the current issues in sol-gel reaction kinetics. Many times seemingly modest changes in reactants or reaction conditions can lead to substantial differences in the overall reaction rates and pathways. For example, qualitative features of the reaction kinetics can depend on catalyst concentration. At very high acid-catalyst concentrations, reverse are significant for TMOS sol-gels, while for moderate acid-catalyst concentrations, reverse reactions are substantially reduced. The reaction kinetics are substantially reduced. The reaction kinetics of two similar tetraalkoxysilanes: tetramethoxysilane (TMOS) and tetraethoxysilane (TEOS), can be markedly different under identical reaction conditions. Under acid-catalyzed reaction conditions, a TMOS sol-gel undergoes both water-and alcohol-producing condensation reactions while a TEOS sol-gel undergoes only water-producing condensation. The early time hydrolysis and condensation reactions of a TMOS sol-gel are statistical in nature and can be quantitatively described by a few simple reaction rate constants while the reaction behavior of a TEOS sol-gel is markedly nonstatistical. A comprehensive theory of sol-gel kinetics must address diverse experimental findings. 9 refs., 3 figs., 1 tab.

The performance of battery charge controllers and their effects on the system are a critical concern for stand-alone photovoltaic systems with battery storage. Many types of charge controllers are being marketed today, and designers need to understand more about their performance and compatibility with different kinds of batteries and systems. This paper describes the evaluations and selected interim test results from eight different models of small (approx. 10 amps) charge controllers. They are being subjected to a comprehensive test program including thorough electrical characterizations at selected temperatures, photovoltaic inputs and load levels. After electrical characterizations, the charge controllers are divided into concurrent evaluation paths. One path consists of side-by-side operational systems tests in which the charge controllers are installed in identical stand-alone PV systems. The other path consists of continuous environmental and electrical cycling in which the controllers are subjected to programmed electrical inputs, temperatures, and relative humidities. Recharacterizations of all controllers are addition, selected custom tests are performed on identical models to determine response to transients, installation issues and system compatibilities. The data presented here include measured electrical characteristics of the controllers, temperature effects, operational performance, and interface measurements at the array, battery and load. 8 refs., 9 figs., 4 tabs.

In the testing of active microwave components, a common test procedure is to evaluate a device's performance when subjected to an all-phase, constant-standing-wave-ratio (APCS) load pull. Such a test specification is useful in verifying a device's stability and mismatch performance. Typically, APCS pulls are tediously performed by hand, with manually operated tuners. However, with the advent of mechanical, computer-controlled tuners, it is how possible to automate this procedure. At Sandia, the goal was to integrate an APCS pull capability into a multi-test, single-connection tester. (The single-connection concept implies that many test, such as network analysis, spectral analysis, and noise figure measurements can be made from a one-time, device-to-tester connection). Consequently, the slide-screw tuner was the obvious choice due to its removable probe capability. Hence, it became necessary to develop a custom algorithm capable of utilizing the tuner in an impedance-finding mode. The general concept used in implementing this capability was to empirically characterize the tuner over and acceptable range of tuner positions, and then use this characterization to intelligently predict the tuner positions needed to present the desired impedance. 4 figs.

Conductor development is one of the major long term goals in high temperature superconductor research. In this paper we report on two promising processing technologies that have been utilized to produce superconducting HTS conductors. First, melt spun YBa{sub 2}Cu{sub 3}O{sub 7} fibers rapid thermal processed for 1--8 sec at 950 to 1075{degree}C have {Tc}'s to 92 K, J{sub c}'s to 1100 A/cm{sup 2} and the orthorhombic twinned morphology typical for high quality YBa{sub 2}Cu{sub 3}O{sub 7}. A processing matrix of time, temperature and composition for these fibers shows that slightly CuO-rich starting compositions give the best results. Second, silver tube encapsulated wires of Bi{sub 1.7}Pb{sub 0.3}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} have been made by extrusion, wire drawing and cold rolling. The resulting tapes show orientation of the crystallites, zero resistance up to 100K and improved magnetic hysteresis above 50 K. The combination of mechanical reprocessing and extended thermal anneals near 850{degree}C appears to significantly improve these materials. 13 refs., 7 figs.

This paper discusses the ability of an adaptive line enhancer (ALE) driven by the least-mean-squares (LMS) algorithm to track the frequency of a chirping signal in broadband noise. The dynamic behavior of the weights is described and a weight tracking error bound is derived in terms in chirp rate. Frequency tracking and weight behavior are illustrated in examples. 6 refs., 7 figs.

Microfabricated series-arrays of Josephson junctions have been developed which are capable of producing quantized voltage levels over a wide voltage range. These arrays have been used in a calibration system since February 10, 1987 to maintain the US Legal Volt at the National Institute of Standards and Technology (NIST, formerly NBS). A similar system within the Primary Standards Laboratory (which is operated for the Department of Energy, Albuquerque Operations Office by Sandia National Laboratories (SNL)) has been in operation since July, 1989. Measurements of the temperature dependence of the array's quantized voltage states and DC characteristics are reported here. 8 refs., 2 figs.

As computers become increasingly powerful, the constitutive models used in structural analysis codes become increasingly sophisticated. With the current generation of supercomputers, it now seems reasonable to consider incorporating relatively detailed representations of the multiaxial deformation response of engineering alloys. To aid in the development of such models and to allow measurement of their constituent parameters, we have designed a complex multiaxial deformation test system. The system to be described has been developed to perform non-proportional cycling of thin-walled metal tubes using internal/external fluid pressure and tensile/compressive axial loading. It has been added to an existing MTS 490 kN load frame with a PDP 11/34-based computer control system. Features of interest include; specimen grips, the high pressure chamber, the hydraulic intensifier and controller, and associated valving and switching. Initial software for this system has been written on the PDP 11/34 in the MTS MultiUser-BASIC language to perform simple proportional multiaxial cyclic deformation to a prescribed effective plastic strain limit.

This paper explains the newly implemented new material (NM) sampling rationale for weapon production developed by Frank W. Mueller, SNL/7266, and approved by DOE. Our experience with weapon production programs has been primarily limited to production lengths of five years or less. As more recent programs, such as the W80, are moving toward increasingly longer production phases, it has become apparent that our previous sampling rationale may have required excessive new material samples. 3 refs.

Radiation-induced interface traps in Si-gate MOS devices follow an E{sup {minus}1/2} electric field dependence for E {ge} +0.13 MV/cm when electron-hole recombination effects are included. A hybrid model involving hole trapping and hydrogen transport is suggested. 20 refs., 4 figs.

The Direct Absorption Receiver (DAR) concept was proposed in the mid-1970s as an alternative advanced receiver concept to simplify and reduce the cost of solar central receiver systems. Rather than flowing through tubes exposed to the concentrated solar flux, the heat absorbing fluid (molten nitrate salt) would flow in a thin film down a flat, nearly vertical panel and absorb the flux directly. Potential advantages of the DAR over conventional tubular designs include a substantially simplified design, improved thermal performance, increased reliability and operating life, as well as reduced capital and operating costs. However, before commercial-scale designs can be realized, a method for controlling droplet ejection from the panel must be developed. In this paper, we present a new DAR design, which has the potential to control these droplets. The design employs four flat panels that are sloped backwards 5 degrees, wind spoilers, and air curtains. A systems analysis is presented indicating that the levelized-energy cost of the quad geometry should be very similar to cylindrical geometry that was originally proposed for the DAR concept. 19 refs., 5 figs., 3 tabs.

A sodium reflux pool-boiler solar receiver has been tested on a nominal 75-kW{sub t} parabolic-dish concentrator. The purpose was to demonstrate the feasibility of reflux-receiver technology for application to Stirling-engine dish-electric systems. In this application, pool boilers (and more generally liquid-metal reflux receivers) have a number of advantages over directly-illuminated tube receivers. The advantages, to be discussed, include more uniform temperature, which results in longer lifetime and higher temperature available to the engine. 17 refs., 10 figs.

Over the next several decades, it is expected that the use of renewable energy technologies will greatly expand as these technologies mature, as the cost of conventional energy supply increases, and as the environmental impact of fossil fuel usage is better understood. A critical question is whether the impact of renewables, in terms of displaced fossil fuel use and reduced environmental effects, can be significant. Certainly, public policy will have dramatic effects on this question. Given a positive policy environment, renewables have the potential to displace a significant fraction of projected energy use within 30-40 years. For the United States, renewables could contribute as much as 25-55 exajoules of energy annually by the year 2030, or 15-35{percent} of the projected total US energy consumption. 12 refs., 6 figs.

Use of the MIT-SNL Period-Generated Minimum Time Control Laws for the automated increase of neutronic power from subcritical conditions has recently been demonstrated. The use of these laws is advantageous because they provide the speed at which a control device should be withdrawn in order to generate a specified period. Two strategies were investigated. The first was the direct use of the MIT-SNL laws for the entire transient, startup plus operation at power. The second was to add reactivity at a constant rate until criticality was achieved and then to transfer control to the MIT-SNL laws. Each was evaluated by both simulation and actual experiment under conditions of closed-loop digital control on the Annular Core Research Reactor that is operated by the Sandia National Laboratories. Both approaches were shown to be feasible. The former has the advantage that the power profile will be known during the startup. Its drawback is that an excessively high rate of reactivity change may be needed to initiate the transient. 16 refs., 9 figs.

An experimental study is described that evaluates the potential for using an acoustic borehole television technique to measure fracture dimensions in lost circulation zones encountered in geothermal drilling. A simulated wellbore was constructed of sandstone blocks with adjustable, inclined fractures, stacked in a barrel filled with water. A slim-hole televiewer was used to log the wellbore, and a computer was used to digitize and analyze the data. Televiewer signal perturbations caused by the fractures were studied to evaluate the effects of fracture thickness and signal amplification on the width of the signal perturbation in the digital record. It was found that the signal amplification is applied. Two techniques for determining the correct amplification are described. With the televiewer used in the present study, fractures thicker than 0.15 inch in a 5.1-inch wellbore can be measured to within an accuracy of 5--15%. Fractures as small as 0.031 inch can be detected but cannot be accurately and reliably measured. 1 ref., 15 figs.

We are continuing to see significant progress in the development of photovoltaic (PV) concentrator technology. New record cell and module efficiencies have been achieved, and improvements in cells, cell assemblies, and modules are increasing reliability and decreasing cost. The number of firms actively pursuing PV concentrator module technology has increased substantially in the last three years. Two new concentrator systems were installed last year, and more are likely to be installed in the near future. This paper describes the most significant developments of the last two years, including descriptions of advances in PV concentrator cell technology, module development and reliability activities, the new installations, a new Concentrator Initiative Program, and results of the latest costing study. 26 refs., 8 figs., 1 tab.

The cost goals and calculations in the Five-Year Plan for the National Photovoltaics Program assume that photovoltaic (PV) concentrator modules will have a reliable output and an operational life expectancy of 30 years.'' Although the modules in the few PV concentrator systems fielded to date have so far been reliable, they have not been in the field long enough to establish performance levels for 30 years and are not necessarily representative of newer concentrator designs. Thus, extensive testing and analysis are required to evaluate and establish the reliability of current concentrator module designs. Considerable research has been done to establish appropriate qualification tests, to understand component failure mechanisms, and to obtain reliable materials and designs. Surveys of fielded systems have been conducted and new test and analysis techniques have been developed in the process. This paper discusses the reliability of photovoltaic concentrator modules with an emphasis on the issues that are currently of most concern. 12 refs., 5 figs.

Erosion of POCO graphite by helium in PISCES-A was measured by carbon spectroscopy for a temperature range from 900{degree}-- 2000{degree}C, ion energies of 30--300 eV, ion fluxes of 1 {minus} 6 {times} 10{sup 22} m{sup {minus}2} s{sup {minus}1} and electro temperatures of 4--22 eV. Yields at low energies were higher than predicted in current models. The role of redeposition is discussed. 15 refs., 4 figs.

The In-situ Permeable Flow Sensor is a new type of implantable instrument under development at Sandia National Laboratories that uses thermal boundary layer pertubation techniques to rapidly determine the three-dimensional velocity vector of groundwater flow in soils or permeable geologic media. This sensor is based on the refinement of previous technology, the Convective Heat Flow Probe, developed for the scientific study of the flow of geothermal fluids in thermally active regions of the earth's crust. The Convective Heat Flow Probe was designed as a logging tool for use in open or uncased boreholes. The newer In-situ Permeable Flow Sensor is based on the same theoretical principles but is designed to be permanently buried at waste or cleanup sites where long term monitoring of groundwater flow is of interest. This instrument is sensitive to permeable flows as low as a few meters per year.

Simplified ATPG and fault simulation algorithms, reduced test set sizes, and increased fault coverage are achieved with I {sub DDQ} testing for stuck-at faults. In addition, I {sub DDQ} testing will detect logically redundant and multiple stuck-at faults, and improve the detection of non-stuck-at fault defects. 17 refs., 6 figs., 6 tabs.

The Department of Energy's Multiwell Experiment (MWX) is a field laboratory in the Piceance Basin of Colorado which has two overall objectives: to characterize the low permeability gas reservoirs in the Mesaverde Formation and to develop technology for their production. Different depositional environments have created distinctly different reservoirs in the Mesaverde, and MWX has addressed each of these in turn. This report presents a comprehensive summary of results from the fluvial interval which lies between 4400 ft and 6000 ft at the MWX site. The reservoirs consist of heterogeneous, amalgamated point-bar sequences which form broad meanderbelts which create irregular, but roughly tabular, reservoirs with widths of 1000--2500 ft. Separate sections of this report are background and summary; site descriptions and operations; geology; log analysis; core analysis; in situ stress; well testing, stimulation, fracture diagnostics, and reservoir evaluation in two separate sandstones; stress, fracture diagnostic, and stimulation experiments in an additional sandstone; supporting laboratory studies; and a bibliography. Additional detailed data, results, analyses, and data file references are presented as appendices which are included on microfiche. The results show that stimulation of fluvial reservoirs can be successful if proper care is taken to minimize damage to the natural fracture system. Both an accelerated leakoff phenomenon and the ability to alter the in situ stress were quantified. Overall, the fluvial interval offers the highest production potential of the three nonmarine intervals studied. 116 refs., 230 figs., 28 tabs.

This paper presents a discussion of the use of the Nijssen Information Analysis Methodology (NIAM) in the design of an experimenters database. This database is used by physicists and technicians to describe the configuration and diagnostic systems used on Sandia National Laboratories Particle Beam Fusion Accelerator II (PBFA II). The design of this database presented some unique challenges because of the large degree of flexibility required to enable timely response to changing experimental configurations. The NIAM user-oriented technique proved to be invaluable in translating experimenter's requirements into an information model and then to a normalized relational design.

The theory and practice of information engineering is being actively developed at Sandia National Laboratories. The main output of Sandia is information. Information is created, analyzed and distributed. It is the life blood of our design laboratory. The proper management of information will have a large, positive impact on staff productivity. In order to achieve the potential benefits of shared information a commonly understood approach is needed, and the approach must be implemented in a CASE (Computer-Aided Software Engineering) tool that spans the entire life cycle of information. The commonly understood approach used at Sandia is natural language. More specifically, it is a structured subset of English. Users and system developers communicate requirements and commitments that they both understand. The approach is based upon NIAM (Nijssen's Information Analysis Methodology). In the last three years four NIAM training classes have been given at Sandia. The classes were all at the introductory level, with the latest class last October having an additional seminar highlighting successful projects. The continued growth in applications using NIAM requires an advanced class. The class will develop an information model for the Ultimate CASE Tool.'' This paper presents the requirements that have been established for the Ultimate CASE Tool'' and presents initial models. 4 refs., 1 tab.

Sandia National Laboratories joined with two other laboratories, Los Alamos National Laboratory and Naval Research Laboratory, to study and implement a highly parallelized tracker/correlator algorithm. Significant progress was made at Sandia on a specific algorithm and code. This report summarizes the accomplishments by Sandia during FY '89 on this project. 12 refs., 4 figs., 2 tabs.

This paper and a companion paper show the traditional limits on amplitude and frequency that can be generated in a laboratory test on a vibration exciter can be substantially extended. This is accomplished by attaching a device to the shaker that permits controlled metal to metal impacts that generate high frequency, high acceleration environment on a test surface. A companion paper (Reference 1) shows that a sinusoidal or random shaker input can be used to generate a random vibration environment on the test surface. This paper derives the three response components that occur on the test surface due to an impact on the bottom surface and the base driven response from the shaker input. These response components are used to generate impulse response functions and frequency response functions which are used in the companion paper to derive power spectral density functions for the overall response. 9 refs., 8 figs.

High average power magnetic pulse compression systems are now being considered for use in several applications such as the High Power Radiation Source (HiPoRS) project. Such systems will require high reliability magnetic switches (saturable inductors) that are very efficient and have long lifetimes. One of the weakest components in magnetic switches is their interlaminar insulation. Considerations related to dielectric breakdown, thermal management of compact designs, and economical approaches for achieving these needs must be addressed. Various dielectric insulation and coating materials have been applied to Metglas foil in an attempt to solve the complex technical and practical problems associated with large magnetic switch structures. This work reports various needs, studies, results, and proposals in selecting and evaluating continuous coating approaches for magnetic foil. Techniques such as electrophoretic polymer deposition and surface chemical oxidation are discussed. We also propose continuous photofabrication processes for applying dielectric ribs or spacers to the foil which permit circulation of dielectric liquids for cooling during repetitive operation. 10 refs., 8 figs., 11 tabs.

This paper and a companion paper show that the traditional limits on amplitude and frequency that can be generated in a laboratory test on a vibration exciter can be substantially extended. This is accomplished by attaching a device to the shaker that permits controlled metal to metal impacts that generate a high acceleration, high frequency environment on a test surface. A companion paper derives some of the mechanical relations for the system. This paper shows that a sinusoidal shaker input can be used to excite deterministic chaotic dynamics of the system yielding a random vibration environment on the test surface, or a random motion of the shaker can be used to generate a random vibration environment on the test surface. Numerical examples are presented to show the kind of environments that can be generated in this system. 9 refs., 9 figs.

Charged-particle simulations in three dimensions are now performed routinely in the Pulsed Power Sciences Directorate at Sandia with the QUICKSILVER suite of codes. QUICKSILVER is a multitasked, finite-difference, three-dimensional, fully relativistic, electromagnetic, particle-in-cell code developed at Sandia. It is targeted for use on current and near-term supercomputers, such as the Cray X-MP/416, which are characterized by large, shared central memories and multiple processors. QUICKSILVER has already been used to simulate ion diodes, magnetically insulated transmission lines, microwave devices, and electron beam propagation. QUICKSILVER is actually a suite of codes; in addition to the main simulation code there are several support codes. The problem geometry is generated with a preprocessor and the simulation results are examined with one or more postprocessors. The MERCURY preprocessor assists the user in defining the mesh, boundary conditions, and other input parameters. The FLASH and AVS postprocessors are used to examine a wide variety of simulation output, including 3D rendering of particle positions, conductor surfaces, and scalar and vector quantities. The PLOTPFF postprocessor displays 2D slices and 1D pencils derived from 3D scalar and vector quantities. Additionally, time histories of various simulation quantities can be examined and manipulated with the IDR postprocessor. This paper describes the suite in detail. 9 refs., 4 figs.

We report the first experiments evaluating the beam generation by the new 4-MV RLA injector. Beams of 15 to 27 kA current were produced and successfully transported up to the first post-accelerating cavity (ET-2), 1.3 m downstream. The beam radius was measured with an x-ray pin-hole camera and found to be equal to 5 mm. We selected an apertured ion-focused foilless diode among the various available diode options. It is the simplest and easiest to operate and can be adjusted to provide variable beam impedance loads. Experimental results will be presented and compared with numerical simulations.

For many years, the protection and control of classified documents has been a concern of administrative and management personnel. Recent thefts of documents has increased this concern and has led to high level committee investigations into improved classified document protection techniques. Better methods must be found to improve classified document protection and control systems. From preliminary investigations, it was determined that there is not one technique or method that alone would provide adequate protection of classified documents. Instead, a systematic approach that would utilize several components must be used. These components would limit the unauthorized access to classified documents, improve the accountability of documents, increase the protection of documents during transfers, protest classified documents against unauthorized reproduction, protect classified documents against unauthorized removal from a security area, and verify that documents that have been flagged for destruction are actually physically destroyed. This study investigates several techniques that could be implemented in each of these six areas. 8 refs.

This is a brief report about a Sandia National Laboratory facility which can provide high-thermal flux for simulation of nuclear thermal flash, measurements of the effects of aerodynamic heating on radar transmission, etc

This paper summarizes a cost-benefit assessment of the seismic design of the waste-handling facilities associated with the prospective high-level waste repository at Yucca Mountain, Nevada. It provides a very brief description of the methodology used and the costs and benefits of varying design levels for vibratory ground motions and surface fault displacements for structures, components, and equipment that are important to safety in the waste-handling facilities. 3 refs., 7 figs.

The problem of radiative heat transfer through a gray, emitting, absorbing, and scattering medium with uniform optical properties is reduced to one without scattering through two techniques. One uses scaling laws, and the other uses a self-consistent effective gas temperature. The scaling laws are derived via the P1 approximation to the radiative transfer equation and can be applied to multidimensional problems with nonisothermal media. The effective temperature method is presently restricted to isotropic scattering and isothermal media. Both methods are evaluated in the current study as a function of scattering albedo, wall emissivity, and optical thickness for two different geometries, and two sets of wall and gas temperatures. The effects of scattering anisotropy are also assessed for the P1 method.

Unsteady Surface Element (USE) methods are applied to a model of a thermocouple wire attached to a thin disk. Green's functions are used to develop the integral equations for the wire and the disk. The model can be used to evaluate transient and steady state responses for many types of heat flux measurement devices including thin skin calorimeters and circular foil (Gardon) heat flux gages. The model can accommodate either surface or volumetric heating of the disk. The boundary condition at the outer radius of the disk can be either insulated or constant temperature. Effect on the errors of geometrical and thermal factors can be assessed. Examples are given.

The problem of determining the mechanical states inside wound capacitor rolls is addressed through the application of two dimensional, linear elasticity. Allowances are made for heterogeneous wound construction of the capacitor, orthotropic material behavior of the capacitor constituents, and arbitrary winding tension. A key element in the formulation is the derivation of material properties for a wound, orthotropic layer which is equivalent in behavior to a stack of dissimilar plies such as are actually wound on the capacitor simultaneously during one turn of the mandrel. The dissimilar plies are necessary by virtue of the conductor and dielectric materials which must be present in a capacitor. The derivation of predictive equations is based on winding the equivalent layer on an appropriate mandrel, followed by a recovery of the individual ply responses.

The determination of the fully plastic response and pressure limit of high pressure containment structures is of considerable importance in design. The plastic-strain response during and following autofrettage operations, in comparison with the limiting strain condition, is of special interest. This paper presents the results of an analysis method for thick wall, high pressure, cylinders where the effective plastic strain distribution through the thickness is the material response variable of primary interest. The limiting value of this effective plastic strain depends on the level of tensile-stress triaxiality which also varies through the thickness. This strain-to-failure criterion is used to predict the complete pressure versus strain response and the maximum pressure for test cylinders. A simple method of effective-stress versus effective plastic strain is employed. This model is quantified by data taken from uniaxial, tension, true-stress-strain curves and from the fracture zone of the tensile specimen. A sample calculation is included.

The linear induction accelerator RADLAC II (Radial Line Accelerator II) is being upgraded to produce a 20-MeV, 40-kA, annular electron beam. Prior to the upgrade, RADLAC II produced a 15-MeV, 15-kA electron beam. Modifications to the pulsed power, injector, and magnetic transport have resulted in a faster-rising flat-topped voltage pulse. A high-quality, 40-kA, 2.0-cm-diameter beam with a low perpendicular thermal velocity has been produced from the injector. The high-quality beam has been accelerated through two accelerating gaps. The final four accelerating stages are being added to RADLAC II, and transport experiments through the full accelerator are beginning. Simulations show that the beam quality will be maintained through the entire accelerator.

Experimental and theoretical work have demonstrated that a proper injector design results in the generation of very-high-brightness beams in a field-immersed foilless diode source which is suitable for use on RADLAC II (a high-current linear induction accelerator for electrons). Time-resolved characterization of the high-brightness immersed diode source was achieved using a time-gated, 2-D X-ray imaging technique. The experiments were performed on the 4-MeV IBEX accelerator and produced currents exceeding 40 kA in a 6-mm-radius, thin annular beam with a measured thermal transverse velocity of 0.1c. For currents of 30 kA, even brighter beams with β2+ = 0.07 were obtained. At lower currents, beams as small as 2 mm in radius were produced with a smaller cathode tip. In all cases, the measured parameters were consistent with 2-D, PIC (particle-in-cell) simulations.

A test method involving simultaneous imposition of temperature cycles and strain on discrete solder joints in a shear orientation is presented. The stress, microstructure, and number of cycles to failure were monitored. Cycles to failure were determined by a continuous electrical detection method. Sodler joints with composition 60Sn-40Pb and 40Sn-40In-20Pb were tested using the method at 20% shear strain. The 60Sn-40Pb alloy had a shorter fatigue lifetime than did 40Sn-40In-20Pb. This is attributed to heterogenous coarsening that concentrates strain in a small area of the 60Sn-40Pb microstructure. In contrast the 40Sn-40In-20Pb microstructure becomes refined. The heterogeneous coarsening also results in cyclic softening in 60Sn-40Pb, which was not observed in 40Sn-40In-20Pb. Failures initiated within the coarsened band in 60Sn-40Pb at Sn-Sn grain boundaries or phase boundaries. In contrast, failures initiated at the surface of 40Sn-40In-20Pb joints and propagated through both phases of the microstructure.

Three different ion beam transport schemes (achromatic lens, wire-guided transport, and Z-discharge channel) for the light ion beam driver for the Laboratory Microfusion Facility (LMF) are examined analytically. For each case the phase space acceptance area is investigated, including the effects of angular momentum. It is shown that, in real diode/transport configurations, there will be some angular momentum (i.e., φ0 ≠ 0) created, e.g., by combinations of diode microdivergence, beam steering errors, foil scattering, and gas scattering. Both the ballistic/lens case and the channel case can accept φ0 = 0 beams if they can be made, and can also tolerate certain amounts of φ0 ≠ 0. On the other hand, the wire case requires φ0 ≠ 0 in a carefully prepared manner. It is concluded that, in regard to angular momentum, the baseline ballistic case is the most accepting transport scheme. The channel transport scheme is less accepting. The wire transport scheme is the least accepting because it requires a tailored nonzero φ0 distribution to be fully accepted.

The nominal 1000-MJ yield of a Laboratory Microfusion Facility (LMF) pellet requires at least a 1.5-m-radius target chamber to contain the blast. A geometry has been identified that uses an annular ion beam with a center plug, has a total transport length of 4 m, and allows no direct line of sight from the target blast to the ion diode. An analytic model for an achromatic, two-lens system that is capable of transporting a 30-MV, 1-MA Li ion beam over this distance has been developed. The system uses both self-Bθ and solenoidal magnetic lenses. The beam microdivergence requirement is minimized by locating the final solenoidal lens at the target chamber wall. In the present work, the analytic model was verified by PIC (particle-in-cell) transport calculations. A realistic coil system has been designed to supply the required 2-T solenoidal fields. Simulations show that a lithium beam can be transported over the 4-m distance with better than 70% energy and power efficiency, delivering roughly 1 MJ/beam to the target if a 6-mrad microdivergence is achieved at the diode.

The FALCON (Fission Activated Laser CONcept) reactor-pumped laser program at Sandia National Laboratories is examining the feasibility of high-power systems pumped directly by the energy from a nuclear reactor. In this concept we use the highly energetic fission fragments from neutron induced fission to excite a large volume laser medium. This technology has the potential to scale to extremely large optical power outputs in a primarily self-powered device. A laser system of this type could also be relatively compact and capable of long run times without refueling.

The semiconductor product engineers job requires knowledge and expertise related to many different subjects. This report provides guidance for newcomers to product engineering and is a consise reference for all others involved in product engineering. Subjects addressed are Customer/Supplier interactions, component development sequence, production schedule support, component characterization, product specifications, test equipment requirements, product qualification, characterization and development reports, preferred parts list, standard packaging, and finally, classification and security considerations. This guide is intended to help standardize and simplify the component development sequence presently used in the semiconductor product engineering department. 3 figs., 2 tabs.

The Waste Isolation Pilot Plant (WIPP), located in southeastern New Mexico, is a research and development facility to demonstrate safe disposal of defense-generated transuranic waste. Performance assessment comprises scenario development and screening and probability assignment; consequence analysis; sensitivity and uncertainty analysis; and comparison with a standard. This report examines events and processes that might give rise to scenarios for the long-term release of waste from the WIPP and begins to screen and assign probabilities to them. The events and processes retained here will be used to develop scenarios during the WIPP performance assessment; the consequences of scenarios that survive screening will be calculated and compared with the standard. 84 refs., 4 figs., 3 tabs.

Coherent phase transformation occurs under conditions of stress wave loading and there are indications that transformation is dependent on the nonhydrostatic state of stress in the body. Studies under static loading show transformation proceeds at lower confining pressure when combined with shearing stress and similar effects appear to occur under stress-wave loading. Nonlinearities in the stress-strain behavior due to the transformation strain lead to complicated wave propagation, including wave separation and rarefaction shock waves. In the present study a thermodynamic theory of the combined elastic and phase transformtion deformation is developed which incorporates the interrelation of pressure and shear effects. The theory is focused on wave propagation in solids and is compared with earlier experimental work on Oakhall limestone. A thermodynamic Gibbs potential is derived for the material and a phase equilibrium relation identified, which constrains the volume and shape change through the transformation. The theory is extended to account for the effect of microstructural heterogeneities on the transformation process which has been observed experimentally.

This report describes a demonstration of the performance assessment methodology for the Waste Isolation Pilot Plant (WIPP) to be used in assessing compliance with the Environmental Protection Agency. This demonstration incorporates development and screening of potentially disruptive scenarios. A preliminary analysis of the WIPP disposal system's response to human intrusion scenarios produces preliminary complementary cumulative distribution functions (CCDFs) used to assess the compliance of the WIPP with the Containment Requirements of the Standard. The conceptual model of the disposal system consists of geologic, hydrologic, and disposal system subsystems along with the physical and chemical processes associated with these subsystems. Parameter values defining the systems contain uncertainties and modeling approximations of such a disposal system contributes to those uncertainties. The WIPP compliance assessment methodology consists of a system of techniques and computer codes that estimate releases of radionuclides from the disposal system, incorporating analysis of the parameter uncertainties in the estimates. Demonstration CCDFs are presented, but are not yet credible enough to judge the probability of compliance of the WIPP with the EPA Standard. 60 refs., 75 figs., 30 tabs.

The structural response of plasma armature railguns to the electromagnetic load imposed during operation has a significant effect on performance. The railgun support structure must minimize bore deformation; thus stiffness and strength are important design parameters. The step by step evolution of the design toward a structure which will tolerate operation with 500 to 700 kA rail currents is presented. The design effort started with the traditional rail/insulator core structure contained within a V-block which provides a preload. Non-linear dynamic analyses together with model tests were used to assess the effects of changes in geometry, materials, and preload on the railgun structural performance. 39 figs., 5 tabs.

The ignition of reactive powders by a semiconductor bridge (SCB) is analyzed by applying a multiphase flow model based upon the theory of mixtures. The hot plasma produced by the SCB permeates the cold granular explosive, deposits its latent heat upon fusing to the grains, therby heating the explosive granular surfaces to energy states required for self-sustained reaction. This mechanism is predicted to heat the granular explosive in a region local to the SCB to temperatures well above those required for thermal ignition. The analysis demonstates that this mechanism explains the prompt ignition of explosives using SCB's as opposed to the conductively controlled heating of conventional bridgewires. 16 refs., 14 figs., 1 tab.

AEROPLT is an interactive, user-friendly, general purpose plot code for plotting tabular data from multiple files. This DISSPLA-based code is convenient and easy to use while permitting great flexibility for users who want to customize their plots. A series of questions leads the user through the program and permits a return to specific portions of the code for plot refinement. Multidevice capability permits the user to plot on the terminal, write to a file for hardcopy plots, or do both simultaneously. An easily modified Setup File is used to store the terminal and hardcopy type codes, plot and text dimensions, and default plot specifications. Parameters for individual plots are written to a Restart File which can easily be edited to change subsequent plots. Additional capabilities are: color plots; a convenient method (similar to TEX) to implement all DISSPLA fonts, character sets, and math alphabets; superscripts, subscripts, underline, and italicize; and plots of the results of mathematical functions of the input data. 12 figs., 21 tabs.

Potentially hazardous test activities have historically been a part of Sandia National Labs mission to design, develop, and test new weapons systems. These test activities include high speed air drops for parachute development, sled tests for component and system level studies, multiple stage rocket experiments, and artillery firings of various projectiles. Due to the nature of Sandia's test programs, the risk associated with these activities can never be totally eliminated. However, a consistent set of policies should be available to provide guidance into the level of risk that is acceptable in these areas. This report presents a general set of guidelines for addressing safety issues related to rocket flight operations at Sandia National Laboratories. Even though the majority of this report deals primarily with rocket flight safety, these same principles could be applied to other hazardous test activities. The basic concepts of risk analysis have a wide range of applications into many of Sandia's current operations. 14 refs., 1 tab.

In this report, we examine two global energy consumption scenarios and corresponding nonenergy scenarios to determine how each will contribute to the greenhouse effect and global warming. A steady emissions trend scenario assumes only modest energy conservation and little change in the world's energy consumption patterns and nonenergy emissions. A reduced emissions trend scenario assumes significant conservation, switching from a more carbon-intensive energy source mix to a less intensive mix, and reducing nonenergy emissions. Based on the difference between the two scenarios' results, our conclusions are that it is possible to reduce global warming by over 50% using a combination of conservation and efficiency improvements, increased use of nuclear, geothermal, and solar/renewable energy sources, and reduced nonenergy emissions. 34 refs.

This report summarizes the results and conclusions generated by the US Nuclear Regulatory Commission sponsored Fire Protection Research Program at Sandia National Laboratories. Efforts conducted from the programs inception in 1975 through 1987 are discussed. The individual efforts are discussed within a framework based on specific areas of investigation. Early efforts are presented in the context of investigations of specific regulatory concerns. Later efforts are presented within the context of an integrated investigation of fire safety issues. This integrated approach considers the fire safety issue in terms of (1) source fire characterization, (2) detection and suppression system effectiveness, (3) room effects, (4) equipment response, and (5) room-to-room fire effects. The report provides a complete bibliography of reports and journal articles generated as a result of these efforts with a cross-reference listing of major reports to specific efforts. 98 refs., 23 figs., 20 tabs.

Gas holdup data for oleci acid at 291 K and for 1018 steel at 1823 K has been taken for nitrogen sparging gas. The liquid levels have been measured using a real time x-ray technique. The data have been compared to correlations from the literature to assess the appropriate correlations for use in calculating gas holdup for molten core debris in reactor accident calculations. A suitable correlation has been determined as well as coefficients for use in a drift flux model. The correlation is in the form {alpha} = 0.128 M{sup -0.0207} jg*{sup 0.584} where {alpha} is holdup, M is the Morton Number and jg* is the dimensionless gas flux through the liquid. 19 refs., 9 figs., 9 tabs.

A method to determine the dynamic shape factor of an aerosol from cascade impactor and TSI Aerodynamic Particle Sizer (APS) distribution measurements is presented and demonstrated. The response of the APS to nonspherical, porous particles is derived after the fashion of Wang and John (1987). This method does not require microscopy or chemical analytical techniques and as such is an improvement over previous methods. 37 refs., 13 figs., 1 tab.

SAVI (Systematic Analysis of Vulnerability to Intrusion) is a PC-based software package for modeling and analyzing physical protection systems. SAVI implements several features that make it a unique product. First, the user interface for site modeling and data entry is simple and flexible. Second, the SAVI model analyzes all adversary paths to the target location and, if selected, all exit paths from the target location. Third, a reference catalog and database are included that define the protection elements and safeguards components, and give detection and delay performance values for the components. Finally, SAVI's results are output in graphic form and include recommendations for upgrade.

This paper discusses the following topics: theoretical predictions of valence and conduction band offsets in III-V semiconductors; reflectance modulation of a semiconductor superlattice optical mirror; magnetoquantum oscillations of the phonon-drag thermoelectric power in quantum wells; correlation between photoluminescence line shape and device performance of p-channel strained-layer materials; control of threading dislocations in heteroepitaxial structures; improved growth of CdTe on GaAs by patterning; role of structure threading dislocations in relaxation of highly strained single-quantum-well structures; InAlAs growth optimization using reflection mass spectrometry; nonvolatile charge storage in III-V heterostructures; optically triggered thyristor switches; InAsSb strained-layer superlattice infrared detectors with high detectivities; resonant periodic gain surface-emitting semiconductor lasers; performance advantages of strained-quantum-well lasers in AlGaAs/InGaAs; optical integrated circuit for phased-array radar antenna control; and deposition and novel device fabrication from Tl{sub 2}Ca{sub 2}Ba{sub 2}Cu{sub 3}O{sub y} thin films.

This report contains important information on the internationally mandated changes in the unit of the Volt and Ohm which will come into force on January 1, 1990; on how the Primary Standards Laboratory will respond to these changes, and recommendations on how the Contractor Standards Laboratories should respond to these changes. It also contains information about the new Josephson Voltage Standard that is now in operation at the Primary Standards Laboratory, and how the use of this standard will change the way that the Volt is disseminated to the Contractor Standards Laboratories. 1 fig.

EPSILON-2 is a general parallel computer architecture that combines the fine grain parallelism of dataflow computing with the sequential efficiency common to von Neumann computing. Instruction level synchronization, single cycle context switches, and RISC-like sequential efficiency are all supported in EPSILON-2. The general parallel computing model of EPSILON-2 is described, followed by a description of the processing element architecture. A sample code is presented in detail, and the progress of the physical implementation discussed. 11 refs., 14 figs.

In the radiation-hardened, optically triggered thyristor development being carried out jointly by Organizations 1141 and 2531, a theoretical model was needed to assist in designing the devices. This model had to accurately predict thyristor performance (e.g., breakover voltage and holding current) for different fabrication and experimental parameters such as doping, layer thickness, temperature, and incident optical intensity. This report describes a mode we are currently developing that is based on treating a p-n-p-n thyristor as coupled p-n-p and n-p-n transistors. This approach has the advantages of providing tractability of the physics that govern thyristor behavior without requiring extensive numerical computations. When benchmarked by a more rigorous (and, consequently, computationally more complicated) treatment, our model should provide accurate and fast screening of a wide range of thyristor configurations. Section 2 describes the general thyristor configuration we wish to investigate. The derivation of the basic equations for our thyristor model is presented in Sections 3. These equations depends on the saturation currents and multiplication factors at each p-n junction, and on the current gains of p-n-p and n-p-n transistors.

The High Temperature Borehole Televiewer is a downhole instrument which provides acoustic pictures of the borehole walls that are suitable for casing inspection and fracture detection in geothermal wells. The Geothermal Drilling Organization has funded the development of a commercial tool survivable to temperatures of 275{degree}C and pressures of 5000 psi. A real-time display on an IBM-compatible PC was included as part of the development effort. This report contains a User Manual which describes the operation of this software. The software is designed in a menu format allowing the user to change many of the parameters which control both the acquisition and the display of the Televiewer data. An internal data acquisition card digitizes the waveform from the tool at a rate of 100,000 samples per second. The data from the tool, both the range or arrival time and the amplitude of the return signal, are displayed in color on the CRT screen of the computer during the logging operation. This data may be stored on the hard disk for later display and analysis. The software incorporates many features which aid in the setup of the tool for proper operation. These features include displaying and storing the captured waveform data to check the voltage and time windows selected by the user. 17 refs., 28 figs., 15 tabs.

Multi-dimensional radiative transfer in combined mode heat transfer problems was investigated with emphasis on the analysis and characterization of a free-falling particle cloud, direct absorption solar central receiver. A model was developed to calculate the relevant distributions in the curtain while a concentrated solar beam is impinging on the front face of the medium. The discrete ordinated approximation was applied to allow the spectral equation of transfer (EOT) to be modeled as a PDE. Model verification tests were conducted to determine the accuracy of the model. One- and two-dimensional results showed that the discrete ordinates model provides satisfactory estimates of the radiant intensity, the heat flux and the temperature distributions for ordinate sets above S{sub 4} (12-flux approximation) for both the black and gray cases. 75 refs., 69 figs., 13 tabs.

This report describes the results of tests conducted on three different designs of full-size electrical penetration assemblies (EPAs) that are used in the containment buildings of nuclear power plants. The objective of the tests was to evaluate the behavior of the EPAs under simulated severe accident conditions using steam at elevated temperature and pressure. Leakage, temperature, and cable insulation resistance were monitored throughout the tests. Nuclear-qualified EPAs were produced from D. G. O'Brien, Westinghouse, and Conax. Severe-accident-sequence analysis was used to generate the severe accident conditions (SAC) for a large dry pressurized-water reactor (PWR), a boiling-water reactor (BWR) Mark I drywell, and a BWR Mark III wetwell. Based on a survey conducted by Sandia, each EPA was matched with the severe accident conditions for a specific reactor type. This included the type of containment that a particular EPA design was used in most frequently. Thus, the D. G. O'Brien EPA was chosen for the PWR SAC test, the Westinghouse was chosen for the Mark III test, and the Conax was chosen for the Mark I test. The EPAs were radiation and thermal aged to simulate the effects of a 40-year service life and loss-of-coolant accident (LOCA) before the SAC tests were conducted. The design, test preparations, conduct of the severe accident test, experimental results, posttest observations, and conclusions about the integrity and electrical performance of each EPA tested in this program are described in this report. In general, the leak integrity of the EPAs tested in this program was not compromised by severe accident loads. However, there was significant degradation in the insulation resistance of the cables, which could affect the electrical performance of equipment and devices inside containment at some point during the progression of a severe accident. 10 refs., 165 figs., 16 tabs.

The Primary Standards Laboratory (PSL) operates a system-wide primary standards and calibration metrology program for the US Department of Energy, Albuquerque Operations Office (DOE/AL). The PSL mission is to develop and maintain primary standards; to calibrate electrical, physical, and radiation reference standards for member laboratories (DOE/AL integrated contractors); to conduct technical surveys and audits of these laboratories; and to recommend and implement system-wide improvements. This report summarizes activities of the PSL for the first half of 1989 and provides information pertinent to the operation of the DOE/AL Standards and Calibration Program. Specific areas covered include development projects, calibration and special measurements, surveys and audits, and significant events. Appendixes cover certifications and reports, commercial calibration laboratories, PSL memoranda, National Bureau of Standards (NBS)/National Institute of Standards and Technology (NIST) test numbers, and a DOE standards and calibration memorandum.

The connector selection program is a database application that allows engineers to locate information about connectors that meet their requirements. This document describes the design and implementation of the database, the data input application, and the user interface. Nijssen's Information Analysis Methodology (NIAM) was used to characterize the connector data requirements which yielded the database design. This design was transformed into database record structures that were implemented in the relational database management software ORACLE. After the database was in place, data input screens were created to capture the connector data, analyze it, and place it in the proper database record structures. Finally, a user interface was designed and developed that displays or prints the information contained in the database, associated drawings, and documentation related to the program and its data.

Proto II is a nominal 8 terawatt pulsed accelerator which is available for x-ray effects testing. The purpose of this guide is to serve as a basic source of information for prospective users of Proto II. Enclosed is a discussion of the design and operation of the accelerator and a summary of x-ray environmental data. The guide also contains a description of experimental support facilities, data acquisition and analysis systems and general information for users. 4 refs., 22 figs., 5 tabs.

Sandia National Laboratories, under the sponsorship of the United States Nuclear Regulatory Commission, is currently developing test validated methods to predict the pressure capacity of light water reactor containment buildings when subjected to postulated severe accident conditions. These conditions are well beyond the design basis. Scale model tests of steel and reinforced concrete containments have been conducted as well as tests of typical containment penetrations. As a part of this effort, a series of tests was recently conducted to determine the leakage behavior of inflatable seals. These seals are used to prevent leakage around personnel and escape lock doors of some containments. The results of the inflatable seals tests are the subject of this report. Inflatable seals were tested at both room temperature and at elevated temperatures representative of postulated severe accident conditions. Both aged (radiation and thermal) and unaged seals were included in the test program. The internal seal pressure at the beginning of each test was varied to cover the range of seal pressures actually used in containments. For each seal pressure level, the external (containment) pressure was increased until significant leakage past the seals was observed. Parameters that were monitored and recorded during the tests were the internal seal pressure, chamber pressure, leakage past the seals, and temperature of the test chamber and fixture to which the seals were attached. 8 refs., 34 figs., 7 tabs.

An exact solution is derived for one-dimensional radionuclide transport under time-varying fluid-flow conditions including radioactive decay but with the approximation that all radionuclides have identical retardation factors. The solution is used to obtain exact expressions for the cumulative radionuclide mass transported past a fixed point in space over a given time period, and to assess the effects of a periodic perturbation and a step change on the fluid-flow velocity and dispersion coefficient. 14 refs., 3 figs., 3 tabs.

Sandia National Laboratories, in conjunction with the Department of Energy Computer Integrated Manufacturing Program, supports the use of the Department of Energy Data Exchange Format (DOEDEF) subset of IGES (the Initial Graphics Exchange Specification) for exchanges of mechanical product definition data between dissimilar computer aided systems of various types. The background for this position is described here.

This report summarizes about 1260 tests performed on small threaded fasteners (equal to or less than 1/4 inch in diameter and designated as 1/4-20 UNC, {number sign}4-40 UNC, {number sign}2-56 UNC, and 1.0 UNM). Tests determined the tensile strengths of the screws, the lengths of engagement needed to develop the full tensile strengths when the screws were engaged in 6061-T6 Aluminum, Hiperco 50, and 303 Stainless Steel, and whether relationships existed between the tensile strengths and Knoop Micro-Hardness measurements taken on the threaded ends of the screws. 17 figs., 13 tabs.

We studied the sintering behavior of high field chem-prep ZnO varistors using dilatometry and determined how sintering conditions influence the varistor's electrical properties. The dilatometric results indicated that 95% theoretical densities could be obtained with a soak time of only 0.5 hour above 752{degree}C, using a 3{degree}C/min ramp rate; greater shrinkage did not occur for soak temperatures above 752{degree}C. A variety of soak times and temperatures was found to be capable of producing varistors with acceptable electrical properties. The variation in the switching field, E{sub s} (at a current density of 10 A/cm{sup 2}), with soak temperature was found to be significantly less for short soak times than for the standard 16 hour soak time. Annealing sintered pellets at 700{degree}C for 4 hours raised the nonlinearity coefficients by {approximately}25% and decreased E{sub s} by {approximately}10%. This uniform decrease in E{sub s} led to a further reduction in the slope of E{sub s} vs soak temperature for values of E{sub s} in the specified range of interest. Further testing of more samples, of samples from different powder batches, and of samples annealed at various temperatures needs to be performed to verify these results. 19 refs., 10 figs., 1 tab.

A 1:6-scale model of a reinforced concrete containment building was pressurized incrementally to failure at a remote site at Sandia National Laboratories. The response of the model was recorded with more than 1000 channels of data (primarily strain and displacement measurements) at 37 discrete pressure levels. The primary objective of this test was to generate data that could be used to validate methods for predicting the performance of containment buildings subject to loads beyond their design basis. Extensive analyses were conducted before the test to predict the behavior of the model. Ten organizations in Europe and the US conducted independent analyses of the model and contributed to a report on the pretest predictions. Predictions included structural response at certain predetermined locations in the model as well as capacity and failure mode. This report discusses comparisons between the pretest predictions and the experimental results. Posttest evaluations that were conducted to provide additional insight into the model behavior are also described. The significance of the analysis and testing of the 1:6-scale model to performance evaluations of actual containments subject to beyond design basis loads is also discussed. 70 refs., 428 figs., 24 tabs.

In this report we describe the development of an unconventional fabrication process using traditional printed-circuit-board materials for assembly into a geophysical electrical simulator. This simulator serves as a bench top geophysical electrical simulation facility for studying and validating dc and very-low-frequency geophysical responses of interest in geologic formations. Soft copper sheet was laminated to glass/epoxy prepreg, without the use of brown oxide coating or any other adhesion promoter, to form a triangle of compound curvature. These triangles were instrumented by the Advanced Process Technology Division and were then assembled into the final hemisphere by the Organic Materials Division. The back side of the hemisphere assembly was encapsulated in polyurethane foam to provide a rigid structure. 1 ref., 10 figs.

A series of shock-loading experiments on an energetic propellant and its simulant was conducted on a light-gas gun. The purpose of this work was to characterize the shock sensitivity of WAK-2, which is a composite-modified, double-based, booster-rocket propellant and its simulant UGS. The initial objectives were to obtain Hugoniot data, to investigate the pressure threshold at which a reaction occurs, and to measure spall threshold at various impact velocities. The Hugoniot data obtained for the propellant fits the Hugoniot curve provided by the manufacturer of the propellant. A Hugoniot curve developed for the simulant was found to match that of the propellant. The initial density, {rho}{sub 0}, initial bulk sound velocity, C{sub 0}, and constant S values for the energetic propellant WAK-2 and its simulant UGS were 1.85 g/cm{sup 3}, 2.2 mm/{mu}s and 2.66, respectively. The ignition threshold pressure of the WAK-2 was found to be in the range of 3 kbar. A violent reaction was observed for a sample impacted at a pressure of 22 kbar. In spall tests, impact pressures in the range of 1.1 to 3.1 kbar were applied to the propellant/simulant. The propellant exhibited spall strengths {approximately}0.33 kbar, with its simulant being somewhat weaker, {approximately}0.22 kbar. Scanning electron microscopy and electron microprobe analysis were used to characterize the microstructures of the materials and to determine the details of the spall events. 20 refs., 19 figs., 9 tabs.

CEPXS is a multigroup-Legendre cross-section generating code. The multigroup-Legendre cross sections produced by CEPXS enable coupled electron-photon transport calculations to be performed with the one-dimensional discrete ordinates code, ONEDANT. We recommend that the 1989 version of ONEDANT that contains linear-discontinuous spatial differencing and S2 synthetic acceleration be used for such calculations. CEPXS/ONEDANT effectively solves the Boltzmann-CSD transport equation for electrons and the Boltzmann transport equation for photons over the energy range from 100 MeV to 1.0 keV. The continuous slowing-down approximation is used for those electron interactions that result in small-energy losses. The extended transport correction is applied to the forward-peaked elastic scattering cross section for electrons. A standard multigroup-Legendre treatment is used for the other coupled electron-photon cross sections. CEPXS extracts electron cross-section information from the DATAPAC data set and photon cross-section information from Biggs-Lighthill data. The model that is used for ionization/relaxation in CEPXS is essentially the same as that employed in ITS. 43 refs., 8 figs.

Simple mixture rules are used to calculate input parameters for an analytic equation of state package (ANEOS) to model saturated limestone as a homogeneous material. This method is used to determine changes in material parameters as the volume fraction of water in the rock changes. Hugoniots determined from these are compared with experimental and theoretical Hugoniots for saturated limestone samples with various porosity levels. Ground shock calculations are also performed to model a deeply buried 500 kiloton explosion in saturated limestone containing various amounts of water. 37 refs., 29 figs.

The Data Retention Chassis (DRC) is a data acquisition component based on the Motorola 68000 microprocessor. The purpose of the DRC is to download the correct set-up parameters into sixteen Tektronix 7912 digitizers, to verify that the digitizers retain their settings, and (once the digitizers have triggered) to load that data into the DRC battery back-up CMOS memory. The DRC also has a circuit built into it called the COMMAND LINK. With the help of the TA698 Alternate Common Equipment (ACE), the user employs this link to communicate interactively with the digitizers and the DRC. Another circuit built into the DRC is the data stream multiplexer (DSM) for high-speed data transfers.

A boundary layer theory for the flow of power-law fluids in a converging planar channel has been developed. This theory suggests a Reynolds number for such flows, and following numerical integration, a boundary layer thickness. This boundary layer thickness has been used in the generation of a finite element mesh for the finite element code FIDAP. FIDAP was then used to simulate the flow of power-law fluids through a converging channel. Comparison of the analytic and finite element results shows the two to be in very good agreement in regions where entrance and exit effects (not considered in the boundary layer theory) can be neglected. 6 refs., 8 figs., 1 tab.

Sandia National Laboratories, Albuquerque, has been designated as Lead Center for the Exploratory Battery Technology Development and Testing Project, which is sponsored by the US Department of Energy's Office of Energy Storage and Distribution. In this capacity, Sandia is responsible for the engineering development of advanced rechargeable batteries for both mobile and stationary energy storage applications. This report details the technical achievements realized in pursuit of the Lead Center's goals during calendar year 1988.

To provide the assurance that a newly developed system meets customer requirements, certification testing of the system must be performed. The MIVS Program Plan required the generation of a Certification Test Plan, detailing the necessary steps required to certify the performance, reliability and quality of the MIVS. This report explains the results of the multi-element environmental testing, of the safety tests performed on the units, and the mechanical shock and random vibrations tests. 3 figs.

The Modular Integrated Video System (MIVS) was developed to provide a replacement surveillance system for the IAEA's Twin Minolta Film Camera System. This task was sponsored by the Department of Energy (DOE) and the US Program for Technical Assistance to IAEA Safeguards (POTAS). This is the final report describing the development, testing, and production of the MIVS. It begins with the generation of a Program Plan identifying the principal steps necessary for the development of a highly reliable, quality surveillance system. Among these steps were the generation of the functional specifications and the certification test plan. These documents describe prototype development and demonstration, Class III production, environmental testing, reliability testing, field commissioning, and commercial manufacturer selection. Data accumulated from the various steps of the Program Plan are presented in this final report. 10 figs.