This talk is about leadership. Leaders are people at every level in an organization who believe in change and are energized by it. They understand the difficult realities of competitive existence. They motivate and challenge. They provide positive reinforcement -- but are never satisfied with their achievements because opportunities for further improvement are never exhausted. Today, leadership is more important than ever because operating environments are changing at an unprecedented rate. The causes are geopolitical, economic, technological, etc. In fact, everything we know about nature tells us that change is inevitable. History shows quite clearly that human progress is not possible without change. Yet, humans crave stability and permanence. As a consequence, success often leads to complacency. But, demise is inevitable for those who protect the status quo. There exists a growing national awareness that global competitive pressures are forcing on American industry the need for ever higher levels of performance. And, similar forces are necessitating improved performance in DOE's nuclear weapons complex. Today, quality takes on a much larger meaning than it has traditionally. It is attention to cost, schedule and product performance that characterize the modern Quality ethic. This paper discusses the manager's role and the new Quality philosophy. 11 figs.
Coupled thermal-structural finite element calculations of a reflux pool-boiler solar receiver were performed to characterize the operating stresses and to address issues affecting the service life of the receiver. Analyses performed using shell elements provided information for receiver material selection and design optimization. Calculations based on linear elastic fracture mechanics principles were performed using continuum elements to assess the vulnerability of a seam-weld to fatigue crack growth. All calculations were performed using ABAQUS, a general purpose finite element code, and elements specifically formulated for coupled thermal-structural analysis. Two materials were evaluated: 316L SS and Haynes 230 alloys. The receiver response was simulated for a combination of structural and thermal loads that represent the startup and operating conditions of the receiver. For both materials, maximum stresses in the receiver developed shortly after startup due to uneven temperature distribution across the receiver surface. The largest effective stress was near yield in the 316L SS receiver and below 39 percent of yield in the Haynes 230 receiver. The calculations demonstrated that stress reductions of over 25 percent could be obtained by reducing the aft dome thickness to one closer to the absorber. The fatigue calculations demonstrated that the stress distribution near the seam-weld notch depends primarily on the structural load created by internal pressurization of the receiver rather than the thermal, indicating that the thermal loads can be neglected when assessing the stress intensity near the seam-weld notch. The stress intensity factor, computed using the J-integral method and crack opening-displacement field equations, was significantly below the fatigue threshold for most steels. The calculations indicated that the weld notch was always loaded in compression, a condition which is not conducive to fatigue crack growth. 15 refs., 30 figs., 3 tabs.
Algorithms for the authentication of byte sequences are described. The algorithms are designed to authenticate data in the Storage, Retrieval, Analysis, and Display (SRAD) Test Data Archive of the Radiation Effects and Testing Directorate (9100) at Sandia National Laboratories, and may be used in similar situations where authentication of stored data is required. The algorithms use a well-known error detection method called the Cyclic Redundancy Check (CRC). When a byte sequence is authenticated and stored, CRC bytes are generated and attached to the end of the sequence. When the authenticated data is retrieved, the authentication check consists of processing the entire sequence, including the CRC bytes, and checking for a remainder of zero. The error detection properties of the CRC are extensive and result in a reliable authentication of SRAD data.
Monitoring wellhead pressure evolution is the best method of detecting crude oil leaks in SPR caverns while oil/brine interface depth measurements provide additional insight. However, to fully utilize the information provided by these interface depth measurements, a thorough understanding of how the interface movement corresponds to cavern phenomena, such as salt creep, crude oil leakage, and temperature equilibration, as well as to wellhead pressure, is required. The time evolution of the oil/brine interface depth is a function of several opposing factors. Cavern closure due to salt creep and crude oil leakage, if present, move the interface upward. Brine removal and temperature equilibration of the oil/brine system move the interface downward. Therefore, the relative magnitudes of these factors determine the net direction of interface movement. Using a mass balance on the cavern fluids, coupled with a simplified salt creep model for closure in SPR caverns, the movement of the oil/brine interface has been predicted for varying cavern configurations, including both right-cylindrical and carrot-shaped caverns. Three different cavern depths and operating pressures have been investigated. In addition, the caverns were investigated at four different points in time, allowing for varying extents of temperature equilibration. Time dependent interface depth changes of a few inches to a few feet were found to be characteristic of the range of cases studied. 5 refs, 19 figs., 1 tab.
In two earlier reports, we derived a time-temperature-dose rate superposition methodology, which, when applicable, can be used to predict cable degradation versus dose rate, temperature and exposure time. This methodology results in long-term predictive capabilities at the low dose rates appropriate to ambient nuclear power plant aging environments. The methodology was successfully applied to numerous important cable materials used in nuclear applications and the extrapolated predictions were verified by comparisons with long-term (7 to 12 year) results for similar or identical materials aged in nuclear environments. In this report, we test the methodology on three crosslinked polyolefin (CLPO) and two ethylene propylene rubber (EPR) cable insulation materials. The methodology applies to one of the CLPO materials and one of the EPR materials, allowing predictions to be made for these materials under low dose-rate, low temperature conditions. For the other materials, it is determined that, at low temperatures, a decrease in temperature at a constant radiation dose rate leads to an increase in the degradation rate for the mechanical properties. Since these results contradict the fundamental assumption underlying time-temperature-dose rate superposition, this methodology cannot be applied to such data. As indicated in the earlier reports, such anomalous results might be expected when attempting to model data taken across the crystalline melting region of semicrystalline materials. Nonetheless, the existing experimental evidence suggests that these CLPO and EPR materials have substantial aging endurance for typical reactor conditions. 28 refs., 26 figs., 3 tabs.
Effective sealing of the Waste Isolation Pilot Plant (WIPP) shafts will be required to isolate defense-generated transuranic wastes from the accessible environment. Shafts penetrate water-bearing hard rock formations before entering a massive creeping-salt formation (Salado) where the WIPP is located. Short and long-term seals are planned for the shafts. Short-term seals, a composite of concrete and bentonite, will primarily be located in the hard rock formations separating the water-bearing zones from the Salado Formation. These seals will limit water flow to the underlying long-term seals in the Salado. The long-term seals will consist of lengthly segments of initially unsaturated crushed salt. Creep closure of the shaft will consolidate unsaturated crushed salt, thereby reducing its permeability. However, water passing through the upper short-term seals and brine inherent to the salt host rock itself will eventually saturate the crushed salt and consolidation could be inhibited. Before saturating, portions of the crushed salt in the shafts are expected to consolidate to a permeability equivalent to the salt host rock, thereby effectively isolating the waste from the overlying water-bearing formations. A phenomenological model is developed for the coupled mechanical/hydrologic behavior of sealed WIPP shafts. The model couples creep closure of the shaft, crushed salt consolidation, and the associated reduction in permeability with Darcy's law for saturated fluid flow to predict the overall permeability of the shaft seal system with time. 17 refs., 6 figs., 1 tab.
The Strategic Petroleum Reserve (SPR), a 600 million barrel crude oil reserve stored primarily in caverns leached in Gulf Coast salt domes, is maintained by the US Department of Energy (DOE). As part of a continuing program to monitor and characterize changes in the oil stored in the reserve, SPR caverns are periodically sampled at varying depths. Several different kinds of samples are withdrawn including pressurized samples, which enable a determination of the oil's vapor pressure and gas/oil ratio. These two parameters are particularly important to drawdown strategies because if the oil contains significant amounts of gas (therefore having a high vapor pressure and gas/oil ratio), additional equipment and decreased removal rates may be required during drawdown. Past pressurized sampling data was wrought with inconsistencies due to improper pressurized sampling and sample analysis techniques. This report documents the findings of an investigation taken to determine the source of the problems in the existing pressurized sampling and sample analysis methods and to establish reliable and cost effective methods of performing these tasks. In particular, flow-through pressurized sampling technology was found to be the most appropriate method of obtaining reliable samples. The gravity transfer method was found to be the most reliable method of moving the sample from the flow-through tool to a transportation container. In regards to sample analysis, it is recommended that gas chromatography replace the antiquated Podbielniak method, that the gas/oil ratio be measured via standard techniques rather than calculated using equations of state, and that a standard method be used to measure the sample's vapor pressure in a constant temperature PVT cell. 24 refs., 33 figs.
Anoxic corrosion and microbial degradation of contact-handled transuranic waste may produce sufficient quantities of gas over a long time period to generate high pressure in the disposal rooms at the Waste Isolation Pilot Plant (WIPP) repository. Dissipation of pressure by outward gas flow will be inhibited by the low permeability of the surrounding rock and by capillary forces that resist gas penetration into this water-saturated rock. Threshold pressure is the gas pressure required to overcome capillary resistance to initial gas penetration and to the development of interconnected gas pathways that would outward gas flow. The primary objectives of this study are to estimate the magnitude of threshold pressure in the bedded salt that surrounds the WIPP repository and to evaluate the role this parameter plays in controlling the outward flow of waste-generated gas. 54 refs., 9 figs., 4 tabs.
The Heat Source/Radioisotopic Thermoelectric Generator shipping container is a Type B packaging design currently under development by Los Alamos National Laboratory. Type B packaging for transporting radioactive material is required to maintain containment and shielding after being exposed to the normal and hypothetical accident environments defined in Title 10 Code of Federal Regulations Part 71. A combination of testing and analysis is used to verify the adequacy of this package design. This report documents the test program portion of the design verification, using several prototype packages. Four types of testing were performed: 30-foot hypothetical accident condition drop tests in three orientations, 40-inch hypothetical accident condition puncture tests in five orientations, a 21 psi external overpressure test, and a normal conditions of transport test consisting of a water spray and a 4 foot drop test. 18 refs., 104 figs., 13 tabs.
This report describes high voltage dc breakdown tests on various PtAu and Au thick film hybrid microcircuits on alumina (Al{sub 2}O{sub 3}). Samples were prepared with current thick film design and manufacturing rules. The purpose was to determine the voltage margins between current design rules and typical applied voltages on real circuits. We also analyzed what happened during a breakdown event. We used a versatile computer-controlled test set to obtain breakdown data. This showed that design conductors 10 mil wide with equal design spaces on alumina and coated with a fired protective glaze (DuPont 9137) had the highest breakdown values (2700 Vdc). Bare design circuits and Au conductor crossover features had a lower breakdown value (1400 to 1600 Vdc). Both these values are well above logic circuit applied voltages ({le}50v). This may account for the excellent field performance obtained to date. Ambient humidity changes to 43% R.H. and voltage rise rates between 3 and 2300 V/sec had little influence on breakdown values ({le}200 Vdc). Voltage breakdown values were little influenced by our two geometries: point-to-line samples which simulated corners and long parallel line samples. Breakdown behaved like a spark in air rather than an arc. Breakdown in glaze went through it to air rather than along the glaze/alumina interface. The spark was found to be similar to lightning in that it consisted of a string of current pulses lasting a total of 1 to 2 seconds. Spark locations were from surface asperities or defects near but not at the point of minimum optically measured separation. Hence, we found that circuits made using current design rules for hybrid microcircuit manufacture are adequate or conservative as regards safe margins against logic voltage dc breakdown to the extent studied here. 13 refs., 19 figs.
Electromagnetic Interference (EMI) problems have resulted in the redesign of the SANDAC V computer case and shielding of its connecting cables. In this report are detailed discussions on the use of computer models and of the tests performed to solve the EMI problems. Included is documentation on the specific changes made to the SANDAC V computer case and the shielding done on the connecting cables. Also documented are the current EMI capabilities relative to MIL Std. 461.
This report represents the first quarterly submittal of data by Sandia National Laboratories (SNL) for the Department Of Energy (DOE) Headquarters Performance Indicator Program. Secretary of Energy Notice (SEN-29-91) directed that a Department-wide uniform systems of Performance Indicators (PIs) for trending and analyzing operational data to help assess and support progress in improving performance and in strengthening line management control of operations relating to environmental, safety, and health activities'' be developed. Trending and analysis of data depicting the performance of facilities is an essential element in creating a culture of continuous improvement,'' where performance gains are maintained and deteriorating environmental, safety, and health conditions are identified early. In addition, good practices that can benefit other DOE operations areas should be identified. The program defines 21 Pi's grouped into four broad areas: (1) personnel safety; (2) operational incidents; (3) environmental releases (normal operations); and (4) management (including waste generation). SNL is required to submit data on 21 PIs for four facilities/reporting elements that were selected by DOE at Albuquerque and Livermore. 31 figs.
In the certification of packages for transport of radioactive material, the issue of slapdown must be addressed. Slapdown is a secondary impact of the body caused by rotational accelerations induced during eccentric primary impact. In this report, several parameters are evaluated that affect slapdown severity of packages for the transport of nuclear material. The nose and tail accelerations in a slapdown event are compared to those experienced by the same cask in a side-drop configuration, in which there is no rotation, for a range of initial impact angles, impact limiter models, and friction coefficients for two existing cask geometries. In some cases, the rotation induced during a shallow-angle impact is sufficient to cause accelerations at the tail during secondary impact to be greater than those at the nose during initial impact. Furthermore, both nose and tail accelerations are often greater than the side-on accelerations. The results described here have been calculated using the code SLAPDOWN, which approximates the impact response of deformable bodies. Finally, SLAPDOWN has been used to estimate the coefficient of friction acting at the nose and tail for one particular cask during one specific slapdown drop test by comparison of results with experimental data. 2 refs., 16 figs., 3 tabs.
Two methods for modeling arbitrary narrow apertures in finite- difference time-domain (FDTD) codes are presented in this paper. The first technique is based on the hybrid thin-slot algorithm (HTSA) which models the aperture physics using an integral equation approach. This method can model slots that are narrow both in width and depth with regard to the FDTD spatial cell, but is restricted to planar apertures. The second method is based on a contour technique that directly modifies the FDTD equations local to the aperture. The contour method is geometrically more flexible than the HTSA, but the depth of the aperture is restricted to the actual FDTD mesh. A technique to incorporate both narrow-aperture algorithms into the FDTD code, TSAR, based on a slot data file'' is presented in this paper. Results for a variety of complex aperture contours are provided, and limitations of the algorithms are discussed.
The results of a Sandia National Laboratories program to design and develop a high-current thermal battery for the Hypersonic Weapons Technology Program are presented. The feasibility of a 200 A, 150 s, 12 Vdc primary battery was demonstrated under ambient conditions. New header feedthrough design concepts were used, and new internal current collectors and internal power leads were considered. The Li(Si)/LiBr-LiCl-LiF/FeS{sub 2} electrochemical system has shown exceptional performance at the high-current operation conditions. A high-rate Zinc/Silver Oxide secondary cell was also evaluated, and the results are presented in this report. These cells exhibited excellent high-rate discharge performance. 5 refs., 19 figs., 8 tabs.
A Performance Assessment Calculational Exercise for 1990 (PACE-90) was coordinated by the Yucca Mountain Site Characterization Project Office for a total-system performance-assessment problem. The primary objectives of the exercise were to develop performance-assessment computational capabilities of the Yucca Mountain Project participates and to aid in identifying critical elements and processes associated with the calculation. The problem defined for PACE-90 was simulation of a ``nominal case`` groundwater flow and transport of a selected group of radionuclides through a portion of Yucca Mountain. Both 1-D and 2-D calculations were run for a modeling period of 100,000 years. The nuclides used, {sup 99}Tc, {sup 135}Cs, {sup 129}I, and {sup 237}Np, were representative of ``classes`` of long-lived nuclides expected to be present in the waste inventory. Movement of the radionuclides was simulated through a detailed hydrostratigraphy developed from Yucca Mountain data specifically for this exercise. The results showed that, for the specified conditions with the conceptual models used in the problem, no radioactive contamination reached the water table, 230 m below the repository. However, due to the unavailability of sufficient site-specific data, the results of this exercise cannot be considered a comprehensive total-system- performance assessment of the Yucca Mountain site as a high-level- waste repository. 46 refs., 94 figs., 19 tabs.
Hydrogen is highly mobile in Si and vitreous SiO2, and it reacts strongly with dangling bonds residing on Si and O atoms. These interactions have important consequences for metal-oxide- semiconductor structures, with noteworthy effects including the passivation of electrically active defects, mediation of radiation sensitivity, chemical passivation of etched Si surfaces, and still poorly understood effects on epitaxial growth from H-containing media. Despite the significance of these H reactions, fundamental understanding of them has remained seriously deficient; the H bonding energies have been known semiquantitatively at best, and the detailed reaction paths and rate-determining energetics of intermediate states have remained largely speculative. We are addressing these issues through a coordinated program of experiment and theory with the goal of a unified, quantitatively predictive understanding.
A semiconductor laser coupled to an external cavity is investigated using a composite-cavity mode approach. Strong frequency hopping for small cavity length changes is obtained, indicating instability of the laser operation against cavity lengths fluctuations.
Results have been obtained on hydrogen dose, dose rate and substrate temperature dependence for hydrogen-assisted thermal donor formation in Czochralski Si. The study combined ion implantation and hydrogen plasma exposure to inject hydrogen, and infrared absorption and spreading resistance probe measurements to detect the donors. Near surface donor concentrations increase with dose and temperature between 350 and 400°C. The penetration depth for thermal donor formation exhibits a $\sqrt{t}$ dependence, and a thermal activation energy of 1.5 ± 0.2 eV.
Adhesion between diamond films synthesized by a CVD method and tungsten has been investigated by a scratch and pull testing methods. Diamond films have been deposited at temperatures from 1173 to 1323 K with a growth rate ranging from 0.2 to 0.45 μm/hour. The films are highly crystalline and are dominated by (100) faces at low temperatures, changing to (111) at higher temperatures. Grain size and residual stress in the films increases with increasing deposition temperature. X-ray diffraction shows the expected diamond diffraction peaks plus peaks attributed to WC and W2C. Raman spectroscopy shows a sharp diamond band for all of the films, with a small broad peak, attributed to amorphous carbon. There is no distinct correlation between diamond/amorphous carbon intensity with deposition temperature. Scratch adhesion testing shows the expected failure mode for brittle coatings, but can not be quantified because of severe degradation of the diamond stylus tip. Sebastion pull testing shows that the failure mode of the films correlates with deposition temperature, but specific adhesion strength values do not. Efforts are continuing to correlate adhesion strength with deposition and structural parameters of the diamond films.
Rational interpolation is frequently useful for generating functions which have an extended range over an abbreviated domain of definition. A simple technique for continued fraction interpolating function evaluation can easily be modified to obtain the function's derivative. This is a useful technique for developing numerical solutions for certain stiff partial differential equations. 9 refs., 2 figs.
This 1990 report contains monitoring data from routine radiological and nonradiological environmental surveillance activities. Summaries of significant environmental compliance programs in progress such as National Environmental Policy Act (NEPA) documentation, environmental permits, environmental restoration, and various waste management programs for Sandia National Laboratories in Albuquerque (SNL, Albuquerque) are included. The maximum offsite dose impact was calculated to be 2.0 {times} 10{sup {minus}3} mrem. The total 50-mile population received a collective dose of 0.82 person-rem during 1990 from SNL, Albuquerque, operations. As in the previous year, the 1990 SNL operations had no adverse impact on the general public or on the environment. This report is prepared for the US Department of Energy in compliance with DOE Order 5400.1. 97 refs., 30 figs., 137 tabs.
There is no routine radioactive emission from Sandia National Laboratories, Tonopah Test Range (SNL, TTR). However, based on the types of test activities such as air drops, gun firings, ground- launched rockets, air-launched rockets, and other explosive tests, possibilities exist that small amounts of depleted uranium (DU) (as part of weapon components) may be released to the air or to the ground because of unusual circumstances (failures) during testing. Four major monitoring programs were used in 1990 to assess radiological impact on the public. The EPA Air Surveillance Network (ASN) found that the only gamma ({gamma}) emitting radionuclide on the prefilters was beryllium-7 ({sup 7}Be), a naturally-occurring spallation product formed by the interaction of cosmic radiation with atmospheric oxygen and nitrogen. The weighted average results were consistent with the area background concentrations. The EPA Thermoluminescent Dosimetry (TLD) Network and Pressurized Ion Chamber (PIC) reported normal results. In the EPA Long-Term Hydrological Monitoring Program (LTHMP), analytical results for tritium ({sup 3}H) in well water were reported and were well below DOE-derived concentration guides (DCGs). In the Reynolds Electrical and Engineering Company (REECo) Drinking Water Sampling Program, analytical results for {sup 3}H, gross alpha ({alpha}), beta ({beta}), and {gamma} scan, strontium-90 ({sup 90}Sr) and plutonium-239 ({sup 239}Pu) were within the EPA's primary drinking water standards. 29 refs., 5 figs., 15 tabs.
PC-1D is a software package for personal computers that uses finite-element analysis to solve the fully-coupled two-carrier semiconductor transport equations in one dimension. This program is particularly useful for analyzing the performance of optoelectronic devices such as solar cells, but can be applied to any bipolar device whose carrier flows are primarily one-dimensional. This User's Guide provides the information necessary to install PC-1D, define a problem for solution, solve the problem, and examine the results. Example problems are presented which illustrate these steps. The physical models and numerical methods utilized are presented in detail. This document supports version 3.1 of PC-1D, which incorporates faster numerical algorithms with better convergence properties than previous versions of the program. 51 refs., 17 figs., 5 tabs.
The disappearance of isocyanate groups in 20 lb/ft{sup 3} rigid polyurethane encapsulating foam (44402-20) was monitored by FTIR spectroscopy leading to an activation energy of 4 kcal/mole. The disappearance of isocyanates can be due to either crosslinking reactions or gas production. Attempting to separate these two reaction paths, we measured the gel time and volume change during cure leading to activation energies of 5 and 6 kcal/mole for the crosslinking and foaming mechanisms respectively. 3 refs., 16 figs.