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Adsorption and desorption studies of cesium on sapphire surfaces

Zavadil, Kevin R.

Adsorption/desorption were studied using combined surface analytical techniques. An approximate initial sticking coefficient for Cs on sapphire was measured using reflection mass spectrometry and found to be 0.9. Thermal Desorption Mass Spectrometry (TDMS) and Auger Electron Spectroscopy (AES) were used to verify that a significant decrease in sticking coefficient occurs as the Cs coverage reaches a critical submonolayer value. TDMS analysis demonstrates that Cs is stabilized on a clean sapphire surface at temperatures (1200 K) in excess of the temperatures experienced by sapphire in a TOPAZ-2 thermionic fuel element (TFE). Surface contaminants on sapphire can enhance Cs adsorption relative to the clean surface. C contamination eliminates the high temperature state of Cs desorption found on clean sapphire but shifts the bulk of the C desorption from 400 to 620 K. Surface C is a difficult contaminant to remove from sapphire, requiring annealing above 1400 K. Whether Cs is stabilized on sapphire in a TFE environment will most likely depend on relation between surface contamination and surface structure.

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System identification of the JPL micro-precision interferometer truss: an overview

Proceedings of SPIE - The International Society for Optical Engineering

Red-Horse, J.R.; Carne, T.G.; Marek, E.L.; Mayes, R.L.; Neat, G.W.; Sword, L.F.

The JPL Micro-Precision Interferometer (MPI) is a testbed for studying the use of control-structure interaction technology in the design of space-based interferometers. A layered control architecture will be employed to regulate the interferometer optical system to tolerances in the nanometer range. This paper summarizes coordinated test and analysis efforts aimed at producing such a model for the MPI structure. Pretest analysis, modal testing and test-analysis reconciliation results are summarized for a series of tests at both the component and full system levels.

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Toxicity evaluation and hazard review Cold Smoke

Archuleta, Melecita M.

Cold Smoke is a dense white smoke produced by the reaction of titanium tetrachloride and aqueous ammonia aerosols. Early studies on the toxicity of this nonpyrotechnically generated smoke indicated that the smoke itself is essentially non-toxic (i.e. exhibits to systemic toxicity or organ damage due to exposure) under normal deployment conditions. The purpose of this evaluation was to review and summarize the recent literature data available on the toxicity of Cold Smoke, its chemical constituents, and its starting materials.

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Smart Document System (SDS) used in managing DOE order`s with electronic Engineering Procedures

Graham, R.; Robbins, D.

The Microsoft (MS) Windows product is widely available for PC`s. There exists many thousands of them at Sandia. All of the MS applications in Windows have a Help file. This help file informs the user ``how to`` use and run that application. It is an ``on-line`` manual. The ``Help Compiler`` was obtained from Microsoft. Use of this compiler enables one to insert text in a form the MS ``Help Engine`` recognizes. This means all of the features of the Help file: Hypertext (hot links), browsing, searching, indexing, bookmarks, annotation, are available for your text. This turns a document into a ``Smart Document.`` The use of this Smart Document System (SDS) for Engineering Procedures (EPs) is described.

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Manufacturing technology. A Sandia Technology Bulletin

Leonard, J.; Doran, L.; Floyd, H.L.; Goetsch, B.; Parrott, L.

This item is a copy of the Dec., 1993 issue of Manufacturing Technology, a Sandia Technology Bulletin. It has information on a number of different projects being conducted by Sandia in the general area of manufacturing sciences. Topics addressed include the following: center for information-technology manufacturing gears up, luctrative flat-panel display market targeted; researchers make copper stick to teflon, patterned adhesion may provide ideal conductor/substrate combination for microcircuits; contact algorithm enhances simulation of manufacturing processes, algorithm efficiently handles previously difficult analyses of punching and cutting operations; national machine tool partnership rolls into action, national laboratories share technology to boost US machine-tool industry; closed-loop MAST system eyes robotic manufacturing, fast, accurate, low-cost sensor demonstrated on furnace brazing.

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Sandia`s research network for Supercomputing `93: A demonstration of advanced technologies for building high-performance networks

Gossage, S.A.; Vahle, M.O.

Supercomputing `93, a high-performance computing and communications conference, was held November 15th through 19th, 1993 in Portland, Oregon. For the past two years, Sandia National Laboratories has used this conference to showcase and focus its communications and networking endeavors. At the 1993 conference, the results of Sandia`s efforts in exploring and utilizing Asynchronous Transfer Mode (ATM) and Synchronous Optical Network (SONET) technologies were vividly demonstrated by building and operating three distinct networks. The networks encompassed a Switched Multimegabit Data Service (SMDS) network running at 44.736 megabits per second, an ATM network running on a SONET circuit at the Optical Carrier (OC) rate of 155.52 megabits per second, and a High Performance Parallel Interface (HIPPI) network running over a 622.08 megabits per second SONET circuit. The SMDS and ATM networks extended from Albuquerque, New Mexico to the showroom floor, while the HIPPI/SONET network extended from Beaverton, Oregon to the showroom floor. This paper documents and describes these networks.

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Impact analysis of Minuteman III Payload Transporter Type III

Stirbis, P.P.

An analysis of the impact of the Minuteman III Payload Transporter Type III into a nonyielding target at 46 m.p.h. and 30 m.p.h., and into a yielding target at 46 m.p.h. is presented. The analysis considers the structural response of the tiedown system which secures the Minuteman III re-entry system to the floor of the payload transporter. A finite element model of the re-entry system, its tiedown system, which includes tie-rods and shear pins, and the pallet plate which is attached to the transporter floating plate, was constructed. Because accelerations of the payload transporter are not known, acceleration data from one-quarter scale testing of the Safe Secure Trailer was used to investigate the response of the tiedown system. These accelerations were applied to the pallet plate. The ABAQUS computer code was used to predict the forces in the members of the tiedown system.

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SAFSIM theory manual: A computer program for the engineering simulation of flow systems

Dobranich, Dean D.

SAFSIM (System Analysis Flow SIMulator) is a FORTRAN computer program for simulating the integrated performance of complex flow systems. SAFSIM provides sufficient versatility to allow the engineering simulation of almost any system, from a backyard sprinkler system to a clustered nuclear reactor propulsion system. In addition to versatility, speed and robustness are primary SAFSIM development goals. SAFSIM contains three basic physics modules: (1) a fluid mechanics module with flow network capability; (2) a structure heat transfer module with multiple convection and radiation exchange surface capability; and (3) a point reactor dynamics module with reactivity feedback and decay heat capability. Any or all of the physics modules can be implemented, as the problem dictates. SAFSIM can be used for compressible and incompressible, single-phase, multicomponent flow systems. Both the fluid mechanics and structure heat transfer modules employ a one-dimensional finite element modeling approach. This document contains a description of the theory incorporated in SAFSIM, including the governing equations, the numerical methods, and the overall system solution strategies.

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Battery energy storage: A preliminary assessment of national benefits (the Gateway Benefits Study)

Akhil, A.; Zaininger, H.; Hurwitch, J.; Badin, J.

Preliminary estimates of national benefits from electric utility applications of battery energy storage through the year 2010 are presented along with a discussion of the particular applications studied. The estimates in this report were based on planning information reported to DOE by electric utilities across the United States. Future studies are planned to refine these estimates as more application-specific information becomes available.

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Final report of the Static Bonding Team, Pantex Plant, Amarillo, Texas

Jones, R.D.; Chen, K.C.; Holmes, S.W.

The integrity of the electrostatic bonding procedures used to equilibrate operating technicians and weapon components was questioned during the course of the quality evaluation assessments of the W70, W68, and B57 dismantlement programs. A multi-disciplined, interlaboratory team was convened on an ad hoc basis to resolve certain static bonding issues. The accomplishments of this team in upgrading the integrity of the bonding process include recommendations on the proper use of wrist straps, training of technicians in their use, and procedures to reduce accumulation of static charge on components during routine handling operations.

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Calibration of the On-Line Aerosol Monitor (OLAM) with ammonium chloride and sodium chloride aerosols

Brockmann, John E.

The On-Line Aerosol Monitor (OLAM) is a light attenuation device designed and built at the Idaho National Engineering Laboratory (INEL) by EG&G Idaho. Its purpose is to provide an on-line indication of aerosol concentration in the PHEBUS-FP tests. It does this by measuring the attenuation of a light beam across a tube through which an aerosol is flowing. The OLAM does not inherently give an absolute response and must be calibrated. A calibration has been performed at Sandia National Laboratories` (SNL) Sandia Aerosol Research Laboratory (SARL) and the results are described here. Ammonium chloride and sodium chloride calibration aerosols are used for the calibration and the data for the sodium chloride aerosol is well described by a model presented in this report. Detectable instrument response is seen over a range of 0.1 cm{sup 3} of particulate material per m{sup 3} of gas to 10 cm{sup 3} of particulate material per m{sup 3} of gas.

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Hydraulic testing of Salado Formation evaporites at the Waste Isolation Pilot Plant site: Second interpretive report

Beauheim, Richard L.

Pressure-pulse, constant-pressure flow, and pressure-buildup tests have been performed in bedded evaporites of the Salado Formation at the Waste Isolation Pilot Plant (WIPP) site to evaluate the hydraulic properties controlling brine flow through the Salado. Transmissivities have been interpreted from six sequences of tests conducted on five stratigraphic intervals within 15 m of the WIPP underground excavations.

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New technologies for item monitoring

Abbott, J.A.; Waddoups, I.G.

This report responds to the Department of Energy`s request that Sandia National Laboratories compare existing technologies against several advanced technologies as they apply to DOE needs to monitor the movement of material, weapons, or personnel for safety and security programs. The authors describe several material control systems, discuss their technologies, suggest possible applications, discuss assets and limitations, and project costs for each system. The following systems are described: WATCH system (Wireless Alarm Transmission of Container Handling); Tag system (an electrostatic proximity sensor); PANTRAK system (Personnel And Material Tracking); VRIS (Vault Remote Inventory System); VSIS (Vault Safety and Inventory System); AIMS (Authenticated Item Monitoring System); EIVS (Experimental Inventory Verification System); Metrox system (canister monitoring system); TCATS (Target Cueing And Tracking System); LGVSS (Light Grid Vault Surveillance System); CSS (Container Safeguards System); SAMMS (Security Alarm and Material Monitoring System); FOIDS (Fiber Optic Intelligence & Detection System); GRADS (Graded Radiation Detection System); and PINPAL (Physical Inventory Pallet).

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History of Sandia National Laboratories` auxiliary closure mechanisms

Weydert, J.C.

An essential component of a horizontal, underground nuclear test setup at the Nevada Test Site is the auxiliary closure system. The massive gates that slam shut immediately after a device has been detonated allow the prompt radiation to pass, but block debris and hot gases from continuing down the tunnel. Thus, the gates protect experiments located in the horizontal line-of-sight steel pipe. Sandia National Laboratories has been the major designer and developer of these closure systems. This report records the history of SNL`s participation in and contributions to the technology of auxiliary closure systems used in horizontal tunnel tests in the underground test program.

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Pyroshock-bibliography

Proceedings, Annual Technical Meeting - Institute of Environmental Sciences

Zimmerman, Roger M.

This paper represents a review copy for text that is to be included in the Shock and Vibration Recommended Practice Document. This section on pyroshock is written as a general introduction to and description of the topic leading to presentation of an extensive bibliography on the subject. Pyroshock is an evolving science that needs continued focus on both achieving improvements in testing and measurement techniques and advancing instrumentation capabilities. when desired predictability and repeatability in practice occurs, hopefully in the near future, recommended practices can be presented.

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Model for heat-up of structures in VICTORIA

Bixler, Nathan E.

VICTORIA is a mechanistic computer code that treats fission product behavior in the reactor coolant system during a severe accident. During an accident, fission products that deposit on structural surfaces produce heat loads that can cause fission products to revaporize and possibly cause structures, such as a pipe, to fail. This mechanism had been lacking from the VICTORIA model. This report describes the structural heat-up model that has recently been implemented in the code. A sample problem shows that revaporization of fission products can occur as structures heat up due to radioactive decay. In the sample problem, the mass of deposited fission products reaches a maximum, then diminishes. Similarly, temperatures of the deposited film and adjoining structure reach a maximum, then diminish.

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Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 2: Appendices

Rechard, Robert P.

This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency`s Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

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Overview of locking systems

Scott, Steven H.

The purpose of this document is to present technical information that should be useful for understanding and applying locking systems for physical protection and control. There are major sections on hardware for locks, vaults, safes, and security containers. Other topics include management of lock systems and safety considerations. This document also contains notes on standards and specifications and a glossary.

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Crystallographic phase identification in the scanning electron microscope: backscattered electron Kikuchi patterns

Proceedings - Annual Meeting, Microscopy Society of America

Michael, Joseph R.

Demonstrated in this study is the phase identification through a combination of backscattered electron Kikuchi patterns (BEKP) and energy dispersive x-ray spectrometry (EDS) by the identification of crystals present on ruthenium oxide thin films on Si. The crystals were identified as RuO2, a tetragonal phase. The charge coupled device (CCD)-based detector is also briefly described. The ability of the CCD-based detector to collect high quality patterns without the use of photographic emulsions enables on-line analysis of the BEKP's.

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Automating the operation of robots in hazardous environments

Harrigan, Raymond W.

Hazardous operations which in the past have been completed by technicians are under increased scrutiny due to high costs and low productivity associated with providing protective clothing and environments. As a result, remote systems are needed to accomplish many hazardous materials handling tasks such as the clean up of waste sites in which the exposure of personnel to radiation, chemical, explosive, and other hazardous constituents is unacceptable. Traditional remote operations have proven to have very low productivity when compared with unencumbered humans. Computer models augmented by sensing and structured, modular computing environments are proving to be effective in automating many unstructured hazardous tasks.

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Photoconductive semiconductor switches for pulsed power applications

IEEE International Pulsed Power Conference - Digest of Technical Papers

Loubriel, Guillermo M.

Photoconductive Semiconductor Switches (PCSS) are being used in, or tested for, many different pulsed power applications as diverse as ultrawideband (UWB) transmitters and high current pulsers. Some aspects of the switches that are relevant to most of the applications are: switch lifetime (longevity), switch opening time (related to the lifetime of carriers in the semiconductor), switching jitter, and the required laser energy. This paper will emphasize the results that we have obtained with Si switches for UWB applications. These include: measurement of switch longevity (a total of 80 Coulombs or 40 C/cm for a 2 cm wide switch and 18.4 Coulombs or 73 Coulombs/cm for a 0.25 cm wide switch), switching at high repetition rates (up to 540 Hz), measurement of carrier lifetime decay rates (a fast one of a few μs, and a slow one of about 330 μs), and measurements on the effect of neutron irradiation on carrier lifetimes. The total charge switched seems to be the highest ever reported for a PCSS. We have used these Si switches in a variety of circuits to produce: a monocycle with a period of about 10 ns corresponding to a center frequency of about 84 MHz, and ringing (many pulse) waveforms with periods of about 1 ns and 7.5 ns corresponding to center frequencies of 770 MHz and 133 MHz. We will also discuss recent studies on the switching properties of GaP.

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Optically controlled current filamentation in GaAs photoconductive semiconductor switches

IEEE International Pulsed Power Conference - Digest of Technical Papers

Zutavern, Fred J.

The use of focused laser beams and fiber optics to control the location and density of current filaments in GaAs photoconductive semiconductor switches (PCSS) is described in this paper. An intensified CCD camera is used to monitor the infrared photoluminescence of the filaments during fast initiation of high gain switching for several sizes of lateral GaAs PCSS (e.g. 0.5×5, 1×5, 2.5×5, 2×30, and 15×20 mm2). The switches are triggered with either a focused, mode-locked, Nd:YAG laser (532 and 1064 nm) or fiber-optically coupled semiconductor laser diodes (approximately 900 nm). The dependencies of the size, location, and density of the current filaments on the optical trigger, switch voltage, and switch current will be discussed. The impact of optically controlled current filaments on device design and lifetime is emphasized. Electro-optical switching amplification is demonstrated using the high gain switching mode of GaAs (lock-on). A single semiconductor laser diode is used to trigger a small GaAs PCSS. This PCSS is used to drive a 15-element laser diode array. Both electrical and optical pulse compression, sharpening, and amplification are achieved. Estimates for electrical and optical power gains are 8000 and 750 respectively.

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Trace water vapor determination in corrosive gases by infrared spectroscopy

Stallard, Brian R.

To extend the life of gas delivery systems and improve wafer yields, there is a need for an in-line monitor of H{sub 2}O contamination. Goal of this project is to develop such an instrument, based on infrared spectroscopy, that has a detection limit of 30 ppB or better and costs $50K or less. This year`s work considered the application of Fourier transform infrared (FTIR) spectroscopy to H{sub 2}O detection in N{sub 2} and HCl. Using a modified commercial FTIR spectrometer and a long-path gas cell, a detection limit of about 10 ppB was demonstrated for H{sub 2}O in N{sub 2} and HCl. This includes about a factor of three improvement achieved by applying quantitative multivariate calibration methods to the problem. Absolute calibration of the instrument was established from absorptivities of prominent H{sub 2}O bands between 3600 and 3910 cm{sup {minus}1}. Methods are described to minimize background moisture in the beam path. Spectral region, detector type, resolution, cell type, and path length were optimized. Resolving the narrow H{sub 2}O bands (FWHM {approx} 0.20 cm{sup {minus}1}) is not necessary to achieve optimal sensitivity. In fact, optimal sensitivity is achieved at 2 to 4 cm{sup {minus}1} resolution, allowing the use of an inexpensive interferometer. A much smaller, second generation instrument is described that will have a conservatively estimated detection limit of 1 ppB. Since the present laboratory instrument can be duplicated in its essential parts for about $90K, it is realistic to project a cost of $50K for the new instrument. An accessory for existing FTIR spectrometers was designed that may be marketed for as little as $10K.

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Results 94326–94350 of 96,771
Results 94326–94350 of 96,771