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Structural support system for a superconducting magnet coil (open access)

Structural support system for a superconducting magnet coil

The purpose of the ESCAR (Experimental Superconducting Accelerator Ring) project, now under way at the Lawrence Berkeley Laboratory, is to gather data and experience in the design and operation of a relatively small synchrotron employing superconducting magnets. Such data are essential to ensure that the design of future large accelerators may proceed in a knowledgeable and responsible manner. One of the many engineering problems associated with a superconducting magnet is the design of the coil suspension system. The coil, maintained at the temperature of liquid helium, must be held rigidly by a structure that does not conduct too much heat into the liquid helium system. The suspension system used on the ESCAR magnets is described. Topics covered include the coil support system requirements, ESCAR magnet support system, and operating experience.
Date: March 3, 1977
Creator: Meuser, R.B.
System: The UNT Digital Library
Effect of simultaneous and sequential detonation on explosive-induced fracture (open access)

Effect of simultaneous and sequential detonation on explosive-induced fracture

Tests were conducted in samples of polystyrene to study the effects of detonation delay on explosively induced fracturing. Two explosive charges in separate emplacement holes were fired at several choices of delay. The effect of free surfaces was minimized to make the experiments a study of blast-induced fracturing in a confined mode, i.e., deeply buried. All fractures formed on radial planes with respect to the emplacement holes. Simultaneous firing connected emplacement holes and produced fractures strongly oriented in the plane of the holes. Delayed firings in the second hole tended to suppress fracturing in the general direction of the first shot hole but to enhance fracturing away from the first hole. The effect was most dramatic in the ''medium'' delay firings; i.e., where the delay time was comparable to the dilatational wave transit time between holes. Using total surface area of cracks as a measure of damage, it was found that no choice of delay, including zero delay, could enhance the per-hole damage above that produced by an isolated shot. For medium delays, in fact, the total damage was measurably reduced.
Date: March 3, 1978
Creator: Swift, R. P.; Schatz, J. F.; Durham, W. B.; Hearst, J. R. & Kusubov, A.
System: The UNT Digital Library
Local energy transfer to TLDS by neutrons and photons (open access)

Local energy transfer to TLDS by neutrons and photons

The local energy transferred from neutrons and photons to TLD materials with respect to energy transferred to biological tissues or air has been calculated. Experimental response of TLDs was measured for photons with energies above 1.5 keV.
Date: March 3, 1980
Creator: Singh, M. S.; Gaines, J. L. & Parlagreco, J. R.
System: The UNT Digital Library
Diagnostics for an XUV/soft x-ray laser (open access)

Diagnostics for an XUV/soft x-ray laser

We have begun investigating the production of an XUV/soft x-ray laser, using our high-powered glass lasers as drivers. A major diagnostic for lasing is the measure of the absolute power produced in the lasing line. I have developed a spectrograph to time-resolved lasing lines in the energy range from 50 eV to greater than 200 eV. the spectrograph combines a transmission grating and x-ray streak camera to produce a flat field instrument. A cylindrical mirror is used in front of the grating to image the source and act as a collecting optic. The efficiency of the components is calibrated so that absolute intensities can be measured. I will compare the performance of this instrument with reflection grating systems. I will also discuss planned improvements to the system which should increase total throughput, image quality, and resolving power.
Date: March 3, 1984
Creator: Kauffman, R.L.; Matthews, D.L.; Ceglio, N. & Medecki, H.
System: The UNT Digital Library
Implicit Plasma Simulation (open access)

Implicit Plasma Simulation

Implicit time integration methods have been used extensively in numerical modelling of slowly varying phenomena in systems that also support rapid variation. Examples include diffusion, hydrodynamics and reaction kinetics. This article discussed implementation of implicit time integration in plasma codes of the ''particle-in-cell'' family, and the benefits to be gained.
Date: March 3, 1985
Creator: Langdon, A. B.
System: The UNT Digital Library
High average power solid state laser power conditioning system (open access)

High average power solid state laser power conditioning system

The power conditioning system for the High Average Power Laser program at Lawrence Livermore National Laboratory (LLNL) is described. The system has been operational for two years. It is high voltage, high power, fault protected, and solid state. The power conditioning system drives flashlamps that pump solid state lasers. Flashlamps are driven by silicon control rectifier (SCR) switched, resonant charged, (LC) discharge pulse forming networks (PFNs). The system uses fiber optics for control and diagnostics. Energy and thermal diagnostics are monitored by computers.
Date: March 3, 1987
Creator: Steinkraus, Robert F.
System: The UNT Digital Library
An integrated, multi-vendor distributed data acquisition system (open access)

An integrated, multi-vendor distributed data acquisition system

A distributed data acquisition system that uses various computer hardware and software is being developed to support magnetic fusion experiments at Lawrence Livermore National Laboratory (LLNL). The experimental sequence of operations is controlled by a supervisory program, which coordinates software running on Digital Equipment Corporation (DEC) VAX computers, Hewlett-Packard (HP) UNIX-based workstations, and HP BASIC desktop computers. An interprocess communication system (IPCS) allows programs to communicate with one another in a standard manner regardless of program location in the network or of operating system and hardware differences. We discuss the design and implementation of this data acquisition system with particular emphasis on the coordination model and the IPCS. 5 refs., 3 figs.
Date: March 3, 1988
Creator: Butner, D.N.; Drlik, M.; Meyer, W.H.; Moller, J.M. & Preckshot, G.G.
System: The UNT Digital Library
Simultaneously time- and space-resolved spectroscopic characterization of laser-produced plasmas (open access)

Simultaneously time- and space-resolved spectroscopic characterization of laser-produced plasmas

The CHROMA laser facility at KMS Fusion has been used to irradiate a variety of microdot targets. These include aluminum dots and mixed bromine dots doped with K-shell (magnesium) emitters. Simultaneously time- and space-resolved K-shell and L-shell spectra have been measured and compared to dynamic model predictions. The electron density profiles are measured using holographic interferometry. Temperatures, densities, and ionization distributions are determined using K-shell and L-shell spectral techniques. Time and spatial gradients are resolved simultaneously using three diagnostics: a framing crystal x-ray spectrometer, an x-ray streaked crystal spectrometer with a spatial imaging slit, and a 4-frame holographic interferometer. Significant differences have been found between the interferometric and the model-dependent spectral measurements of plasma density. Predictions by new non-stationary L-shell models currently being developed are also presented. 14 refs., 10 figs.
Date: March 3, 1988
Creator: Charatis, G.; Young, B. K. F.; Busch, G. E.; Cerjan, C. J.; Goldstein, W. H.; Osterheld, A. L. et al.
System: The UNT Digital Library
CDF: Recent results and future prospects (open access)

CDF: Recent results and future prospects

We present recent results from the Collider Detector at Fermilab. Searches for the top quark have established a lower bound of M{sub top} > 91 GeV/c{sup 2} (at 95% confidence level). A measurement of B{sup o}{bar B}{sup o} mixing has been obtained from b{bar b} {yields} e{mu}, ee events. Measurements of b-quark production have been obtained from e + X events and J/{psi} + K events. The mass of the W boson has been determined to be M{sub W} = 79.91 {plus minus} 0.39 GeV/c{sup 2}. In searching for new gauge bosons, we have obtained the bounds M{sub Z{prime}} > 412 GeV/c{sup 2} and M{sub W{prime}} > 520 GeV/c{sup 2} (at 95% C.L.). The lower limits on the quark and lepton compositeness scales are 1.4 TeV. In the next two years of data collection, we expect significantly more events for numerous types of physics, due to 25 times more beam luminosity, and improvement to the detector. In the longer term, the Main Injector'' upgrade to the accelerator, further improvements to the detector are being planned to exploit the potentials for physics. We discuss prospects for the discovery of the top quark, precise measurement of properties of b quark, and searches …
Date: March 3, 1992
Creator: Yeh, G.P.
System: The UNT Digital Library
CDF: Recent results and future prospects (open access)

CDF: Recent results and future prospects

We present recent results from the Collider Detector at Fermilab. Searches for the top quark have established a lower bound of M{sub top} > 91 GeV/c{sup 2} (at 95% confidence level). A measurement of B{sup o}{bar B}{sup o} mixing has been obtained from b{bar b} {yields} e{mu}, ee events. Measurements of b-quark production have been obtained from e + X events and J/{psi} + K events. The mass of the W boson has been determined to be M{sub W} = 79.91 {plus_minus} 0.39 GeV/c{sup 2}. In searching for new gauge bosons, we have obtained the bounds M{sub Z{prime}} > 412 GeV/c{sup 2} and M{sub W{prime}} > 520 GeV/c{sup 2} (at 95% C.L.). The lower limits on the quark and lepton compositeness scales are 1.4 TeV. In the next two years of data collection, we expect significantly more events for numerous types of physics, due to 25 times more beam luminosity, and improvement to the detector. In the longer term, the ``Main Injector`` upgrade to the accelerator, further improvements to the detector are being planned to exploit the potentials for physics. We discuss prospects for the discovery of the top quark, precise measurement of properties of b quark, and searches for …
Date: March 3, 1992
Creator: Yeh, G. P.
System: The UNT Digital Library
Recovery and recycling of aluminum, copper, and precious metals from dismantled weapon components (open access)

Recovery and recycling of aluminum, copper, and precious metals from dismantled weapon components

Sandia National Laboratories (SNL) is tasked to support The Department of Energy in the dismantlement and disposal of SNL designed weapon components. These components are sealed in a potting compound, and contain heavy metals, explosive, radioactive, and toxic materials. SNL developed a process to identify and remove the hazardous sub-components utilizing real-time radiography and abrasive water-jet cutting. The components were then crushed, granulated, screened, and separated into an aluminum and a precious-and-base-metals fraction using air-tables. Plastics were further cleaned for disposal as non-hazardous waste. New Mexico Bureau of Mines and Mineral Resources assisted SNL in investigation of size-reduction and separation technologies.
Date: March 3, 1994
Creator: Gundiler, I. H.; Lutz, J. D. & Wheelis, W. T.
System: The UNT Digital Library
A comparison of national compliance legislation under the chemical weapons convention (open access)

A comparison of national compliance legislation under the chemical weapons convention

The Chemical Weapons Convention (CWC) is unique among multilateral arms control agreements in requiring national compliance legislation. This paper discusses the compliance legislation enacted by Australia, Germany, Norway, South Africa, and Sweden in anticipation of this agreement entering into force. It compares how these five nations addressed the requirement for legislation to penalize violations of the Convention, as well as how they have developed legal mechanisms to acquire the information about dual-use chemicals that must be declared to the Organisation for the Prohibition of Chemical Weapons. This analysis shows that although different options exist to meet these treaty requirements, areas of consistency between nations are emerging that will encourage universal compliance as the regime matures.
Date: March 3, 1995
Creator: Tanzman, E. A.
System: The UNT Digital Library
Effect of SiO{sub 2} overcoat thickness on laser damage morphology of HfO{sub 2}/SiO{sub 2} Brewster`s angle polarizers at 1064 nm (open access)

Effect of SiO{sub 2} overcoat thickness on laser damage morphology of HfO{sub 2}/SiO{sub 2} Brewster`s angle polarizers at 1064 nm

HfO{sub 2}/SiO{sub 2} Brewster`s angle polarizers are being developed at LLNL for the National Ignition Facility. Damage threshold studies using a 3-ns pulse length 1064-nm laser have revealed a number of different damage morphologies such as nodular ejection pits, plasma scalds, flat bottom pits, and overcoat delaminations. Of these laser damage morphologies, delaminations have the most negative impact on the multilayer stability. By selecting the proper SiO{sub 2} overcoat thickness, the delamination morphology is eliminated without significantly modifying the spectra characteristics of the coating and the functional damage threshold is increased by 2-4x. A model of the thermal mechanical response of the overcoats is presented for various SiO{sub 2} overcoat thicknesses. The overcoat thickness influences the electric-field profile resulting in different thermal gradients between the outer SiO{sub 2} and HfO{sub 2} layers. This modeling effort attempts to understand the relation between the thermal stress distribution in the overcoat and the occurrence of delamination.
Date: March 3, 1997
Creator: Stolz, C. J.; Genin, F. Y.; Reitter, T. A.; Molau, N. E.; Bevis, R. P.; von Gunten, M. K. et al.
System: The UNT Digital Library
Fiber optic cone penetrometer raman probe for in situ chemical characterization of the Hanford underground waste tanks (open access)

Fiber optic cone penetrometer raman probe for in situ chemical characterization of the Hanford underground waste tanks

A field hardened fiber optic Raman probe has been developed for cone penetrometer deployment in the Hanford underground chemical waste storage tanks. The corrosive chemical environment of the tanks, as well as Hanford specific deployment parameters, provide unique challenges for the design of an optical probe.
Date: March 3, 1997
Creator: Kyle, K. R. & Brown, S. B.
System: The UNT Digital Library
Observation of multiple mechanisms for stimulating ion waves in ignition scale plasmas. Revision 1 (open access)

Observation of multiple mechanisms for stimulating ion waves in ignition scale plasmas. Revision 1

The laser and plasma conditions expected in ignition experiments using indirect drive inertial confinement have been studied experimentally. It has been shown that there are at least three ways in which ion waves can be stimulated in these plasmas and have significant effect on the energy balance and distribution in the target. First ion waves can be stimulated by a single laser beam by the process of Stimulated Brillouin Scattering (SBS) in which an ion acoustic and a scattered electromagnetic wave grow from noise. Second, in a plasma where more than one beam intersect, ion waves can Lie excited at the `beat` frequency and wave number of the intersecting beams,, causing the side scatter instability to be seeded, and substantial energy to be transferred between the beams [R. K. Kirkwood et. al. Phys. Rev. Lett. 76, 2065 (1996)]. And third, ion waves may be stimulated by the decay of electron plasma waves produced by Stimulated Raman Scattering (SRS), thereby inhibiting the SRS process [R. K. Kirkwood et. al. Phys. Rev. Lett. 77, 2706 (1996)].
Date: March 3, 1997
Creator: Kirkwood, R.K.; MacGowan, B.J. & Montgomery, D.S.
System: The UNT Digital Library
Cementation of residue ion exchange resins at Rocky Flats (open access)

Cementation of residue ion exchange resins at Rocky Flats

Ion exchange resins have been used to purify nitric acid solutions of plutonium at Rocky Flats since the 1950s. Spent ion exchange resins were retained for eventual recovery of residual plutonium, typically by incineration followed by the aqueous extraction of plutonium from the resultant ash. The elimination of incineration as a recovery process in the late 1980s and the absence of a suitable alternative process for plutonium recovery from resins led to a situation where spent ion exchange resins were simply placed into temporary storage. This report describes the method that Rocky Flats is currently using to stabilize residue ion exchange resins. The objective of the resin stabilization program is: (1) to ensure their safety during interim storage at the site, and (2) to prepare them for ultimate shipment to the Waste Isolation Pilot Plant (WIPP) in New Mexico. Included in the discussion is a description of the safety concerns associated with ion exchange resins, alternatives considered for their stabilization, the selection of the preferred treatment method, the means of implementing the preferred option, and the progress to date.
Date: March 3, 1998
Creator: Dustin, D.F.; Beckman, T.D. & Madore, C.M.
System: The UNT Digital Library
Mars ascent propulsion on a minimum scale (open access)

Mars ascent propulsion on a minimum scale

A concept is presented for a single stage vehicle intended to lift a Mars sample to an orbital rendezvous. At 200 kg liftoff mass, it can potentially be delivered by a Mars Pathfinder size aeroshell. Based on launch vehicle design principles, propellants are pumped from thin-walled low pressure tanks into compact high pressure thrusters. Technical risk is reduced by using non-cryogenic propellants, and by driving piston pumps with heated helium.
Date: March 3, 1998
Creator: Whitehead, J.C. & Guernsey, C.S.
System: The UNT Digital Library
Packaging and transportation system for K-Basin spent fuel (open access)

Packaging and transportation system for K-Basin spent fuel

This paper describes the cask/transportation system that was designed, procured and delivered to the Hanford K-Basin site at Richland, Washington. The performance requirements and design of the various components -- cask, trailer with cask tie-down system, and the cask operation equipment for the load-out pit -- will be discussed. The presentation will include the details of the factory acceptance testing and its results. The performance requirements for the cask/transportation system was dictated by the constraints imposed by the large number of high priority shipments and the spent fuel pool environment, and the complex interface requirements with other equipment and facility designs. The results of the testing form the basis for the conclusion that the system satisfies the site performance requirements. The cask/transportation system design was driven by the existing facility constraints and the limitations imposed by the large number of shipments over a short two-year period. This system may be useful information for other DOE facilities that may be or will be in a similar situation.
Date: March 3, 1998
Creator: Kee, A. T.
System: The UNT Digital Library
Progress in stabilization of plutonium and residues since DNFSB recommendation 94-1 (open access)

Progress in stabilization of plutonium and residues since DNFSB recommendation 94-1

There are approximately 100 metric tons of residues at the Rocky Flats Environmental Technology Site containing approximately 3 metric tons of plutonium. The residues are byproducts of past plutonium operations incinerator ash; pyrochemical salts; graphite; sand, slag, and crucible; and miscellaneous forms of combustibles, glass, metal, and sludges. In September 1993, a report was released (Reference 1) which identified concerns with the chemical stability of the residues and with the integrity of packaging. In May 1997, the Defense Nuclear Facility Safety Board published recommendation 94-1 citing a concern for the residue stability and requiring that the possibly unstable residues be processed within 3 years and all others within 5 years. A risk categorization scheme was developed which assigned a numerical risk to each residue type based on the probability and consequence of occurrence of failures associated with the hazards identified. The residues were ranked for priority of stabilization actions. Urgent concerns were resolved. All residue drums were vented to eliminate the potential for hydrogen and other explosive gas accumulation. Leaded rubber gloves and ion exchange resins were washed to eliminate the explosion potential. An aggressive characterization program was implemented to search for any additional safety or environmental concerns and to …
Date: March 3, 1998
Creator: Ball, J.M. & Dustin, D.F.
System: The UNT Digital Library
Status and use of the Rocky Flats Environmental Technology Site Pipe Overpack Container for TRU waste storage and shipments (open access)

Status and use of the Rocky Flats Environmental Technology Site Pipe Overpack Container for TRU waste storage and shipments

The Pipe Overpack Container was designed to optimize shipments of high plutonium content transuranic waste from Rocky Flats Environmental Technology Site (RFETS) to Waste Isolation Pilot Plant (WIPP). The container was approved for use in the TRUPACT-II shipping container by the Nuclear Regulatory Commission in February 1997. The container optimizes shipments to WIPP by increasing the TRUPACT-II criticality limit from 325 fissile grams equivalent (FGE) to 2,800 FGE and provides additional shielding for handling wastes with high americium-241 (Am-241) content. The container was subsequently evaluated and approved for storage of highly dispersible TRU wastes and residues at RFETS. Thermal evaluation of the container shows that the container will mitigate the impact of a worst case thermal event from reactive or potentially pyrophoric materials. These materials contain hazards postulated by the Defense Nuclear Facilities Safety Board for interim storage. Packaging these reactive or potentially pyrophoric residues in the container without stabilizing the materials is under consideration at RFETS. The design, testing, and evaluations used in the approvals, and the current status of the container usage, will be discussed.
Date: March 3, 1998
Creator: Thorp, Donald T.; Rivera, Michael A. & Geinitz, Richard R.
System: The UNT Digital Library
The use of filtered bags to increase waste payload capacity (open access)

The use of filtered bags to increase waste payload capacity

For the past few years, the Department of Energy has favored the direct disposal of low plutonium content residue materials from Rocky Flats rather than engage in expensive and time consuming plutonium recovery operations. One impediment to direct disposal has been the wattage limit imposed by the Waste Isolation Pilot Plant on hydrogenous materials such as combustibles and sludges. The issue of concern is the radiolytic generation and accumulation of hydrogen and other explosive gases in waste containers. The wattage limits that existed through 1996 restricted the amount of plutonium bearing hydrogenous materials that could be packaged in a WIPP bound waste drum to only a fraction of the capacity of a drum. Typically, only about one kilogram of combustible residue could be packaged in a waste drum before the wattage limit was exceeded resulting in an excessively large number of drums to be procured, stored, shipped, and interred. The Rocky Flats Environmental Technology Site has initiated the use of filtered plastic bags (called bag-out bags) used to remove transuranic waste materials from glove box lines. The bags contain small, disk like HEPA filters which are effective in containing radioactively contaminated particulate material but allow for the diffusion of hydrogen …
Date: March 3, 1998
Creator: Dustin, Donald F.; Thorp, Donald T. & Rivera, Michael A.
System: The UNT Digital Library
Bringing the Fuzzy Front End into Focus (open access)

Bringing the Fuzzy Front End into Focus

Technology planning is relatively straightforward for well-established research and development (R and D) areas--those areas in which an organization has a history, the competitors are well understood, and the organization clearly knows where it is going with that technology. What we are calling the fuzzy front-end in this paper is that condition in which these factors are not well understood--such as for new corporate thrusts or emerging areas where the applications are embryonic. While strategic business planning exercises are generally good at identifying technology areas that are key to future success, they often lack substance in answering questions like: (1) Where are we now with respect to these key technologies? ... with respect to our competitors? (2) Where do we want or need to be? ... by when? (3) What is the best way to get there? In response to its own needs in answering such questions, Sandia National Laboratories is developing and implementing several planning tools. These tools include knowledge mapping (or visualization), PROSPERITY GAMES and technology roadmapping--all three of which are the subject of this paper. Knowledge mapping utilizes computer-based tools to help answer Question 1 by graphically representing the knowledge landscape that we populate as compared with …
Date: March 3, 1999
Creator: Beck, D. F.; Boyack, K. W.; Bray, O. H. & Siemens, W. D.
System: The UNT Digital Library
Compression of Complex-Valued SAR Imagery (open access)

Compression of Complex-Valued SAR Imagery

Synthetic Aperture Radars are coherent imaging systems that produce complex-valued images of the ground. Because modern systems can generate large amounts of data, there is substantial interest in applying image compression techniques to these products. In this paper, we examine the properties of complex-valued SAR images relevant to the task of data compression. We advocate the use of transform-based compression methods but employ radically different quantization strategies than those commonly used for incoherent optical images. The theory, methodology, and examples are presented.
Date: March 3, 1999
Creator: Eichel, P. & Ives, R. W.
System: The UNT Digital Library
Decontaminating the DOE-STD-3013 Inner Container to Meet 10-CFR-835 Appendix D Requirements (open access)

Decontaminating the DOE-STD-3013 Inner Container to Meet 10-CFR-835 Appendix D Requirements

The United States Department of Energy (DOE) has published a standard that specifies the criteria for preparation and packaging of plutonium metals and oxides for safe long-term storage (DOE-STD-3013-96). This standard is followed for the packaging of materials resulting from the disassembly of nuclear weapons at Los Alamos National Laboratory under the Advanced Retirement and Integrated Extraction System (ARIES) project. Declassified plutonium metal or oxide material from the ARES project is packaged into doubly contained and welded type 304L stainless steel containers that comply with the DOE standard. The 3013-96 standard describes requirements for maximum contamination limits on the outer surface of the sealed inner container. These limits are 500 dpm per 100 cm2 for direct measurements and 20 dpm per 100 cm2 for removable contamination. For containers filled, welded, and handled inside a highly contaminated glovebox line, these limits are difficult to obtain. Simple handling within the line is demonstrated to contaminate surfaces from 10,000 to 10,000,000 dpm alpha per 100 cm2. To routinely achieve contamination levels below the maximum contamination levels specified by the 3013-96 standard within a processing operation, a decontamination step must be included. In the ARIES line, this decontamination step is an electrolytic process that …
Date: March 3, 1999
Creator: Martinez, H. E.; Nelson, T. O.; Rivera, Y. M.; Wedman, D. E. & Weisbrod, K. R.
System: The UNT Digital Library