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Ion Desorption Stability in Superconducting High Energy Physics Proton Colliders

Description: In this paper we extend our previous analysis of cold beam tube vacuum in a superconducting proton collider to include ion desorption in addition to thermal desorption and synchrotron radiation induced photodesorption. The new ion desorption terms introduce the possibility of vacuum instability. This is similar to the classical room temperature case but now modified by the inclusion of ion desorption coefficients for cryosorbed (physisorbed) molecules which can greatly exceed the coefficients f… more
Date: May 29, 1995
Creator: Turner, W.C.
Partner: UNT Libraries Government Documents Department
open access

S.M.A.R.T. map: Site map attribute retrieval technique

Description: Plant Engineering`s Space and Site Planning (S&SP) organization at Lawrence Livermore National Laboratory (LLNL) has developed a new tool, which is a computerized mapping system that can graphically illustrate facility characteristics. The current ``base`` map being used is the LLNL Site Map prepared by Plant Engineering`s CADD Support group. Using current information in the Facility Information Tracking System (FITS) database, a Microsoft Excel spreadsheet, an electronic sort can be made, tyin… more
Date: March 29, 1995
Creator: Brown-Rall, M.
Partner: UNT Libraries Government Documents Department
open access

TPX superconducting cable-in-conduit 1995 design and development progress

Description: A unique feature of the magnet system for the Tokamak Physics Experiment (TPX) is that all the magnets are superconducting. With the exception of the outer poloidal coils, the magnet system uses Nb{sub 3}Sn cable-in-conduit conductor; the outer poloidal coils use Nb-Ti cable-in-conduit conductor. We describe the current TPX conductor design and present a progress report on the conductor development. Our strand development contracts have resulted in demonstrating that at least two vendors can pr… more
Date: September 29, 1995
Creator: Zbasnik, J. P.; Martovetsky, N. N. & Hibbs, S. M.
Partner: UNT Libraries Government Documents Department
open access

UNICORN: Misuse detection for UNICOS

Description: An effective method for detecting computer misuse is the automatic auditing and analysis of on-line user activity. This activity is reflected in the system audit record, by changes in the vulnerability posture of the system configuration, and in other evidence found through active testing of the system. In 1989 we started developing an automatic misuse detection system for the Integrated Computing Network (ICN) at Los Alamos National Laboratory. Since 1990 this system has been operational, moni… more
Date: March 29, 1995
Creator: Christoph, Gary G; Jackson, Kathleen A.; Neuman, Michael C.; Siciliano, Christine L. B.; Simmonds, Dennis D.; Stallings, Cathy A. et al.
Partner: UNT Libraries Government Documents Department
open access

Co-wound voltage sensor R&D for TPX magnets

Description: The Tokamak Physics Experiment (TPX) will be the first tokamak to use superconducting cable-in-conduit-conductors (CICC) in all Poloidal Field (PF) & Toroidal Field (TF) magnets. Conventional quench detection, the measurement of small resistive normal-zone voltages (<1 V) in the magnets will be complicated by the presence of large inductive voltages (>4 kV). In the quench detection design for TPX, we have considered several different locations for internal co-wound voltage sensors in the cable … more
Date: September 29, 1995
Creator: Chaplin, M. R.; Martovetsky, N. N. & Zbasnik, J.
Partner: UNT Libraries Government Documents Department
open access

Land mine detection using multispectral image fusion

Description: Our system fuses information contained in registered images from multiple sensors to reduce the effects of clutter and improve the ability to detect surface and buried land mines. The sensor suite currently consists of a camera that acquires images in six bands (400nm, 500nm, 600nm, 700nm, 800nm and 900nm). Past research has shown that it is extremely difficult to distinguish land mines from background clutter in images obtained from a single sensor. It is hypothesized, however, that informatio… more
Date: March 29, 1995
Creator: Clark, G. A.; Sengupta, S. K.; Aimonetti, W. D.; Roeske, F.; Donetti, J. G.; Fields, D. J. et al.
Partner: UNT Libraries Government Documents Department
open access

TPX superconducting Tokamak magnet system: 1995 design and status overview

Description: The TPX magnet preliminary design effort is summarized. Key results and accomplishments during preliminary design and supporting R and D are discussed, including conductor development, quench detection, TF and PF magnet design, conductor bending and forming, reaction heat treating, helium stubs, and winding pack insulation.
Date: September 29, 1995
Creator: Deis, G.; Bulmer, R. & Carpenter, R.
Partner: UNT Libraries Government Documents Department
open access

Continuous Aqueous Tritium Monitoring

Description: Continuous monitoring for tritium in the aqueous effluents of selected Savannah River Site (SRS) facilities is performed using a custom designed system that includes an automated water purification system and a flow-through radiation detection system optimized for tritium. Beads of plastic scintillators coupled with coincidence electronics provide adequate sensitivity (=25kBz/L) for tritium break-through detection int he aqueous discharge stream from these facilities. The tritium effluent water… more
Date: March 29, 1995
Creator: Hofstetter, K. J.
Partner: UNT Libraries Government Documents Department
open access

Consolidated Incineration Facility Tritium Emissions Monitoring

Description: The Savannah River Technology Center, a research and development facility at the US Department of Energy`s Savannah River Site, provides environmental and regulatory compliance support to onsite operations. A new consolidated Incinerator Facility at SRS is being built to treat hazardous and a combination of hazardous and radioactive (mixed) wastes.
Date: March 29, 1995
Creator: Dunn, D. L. & Aggus, J.R.
Partner: UNT Libraries Government Documents Department
open access

A comparison of nodular defect seed geometeries from different deposition techniques

Description: A focused ion-beam milling instrument commonly utilized in the semiconductor industry for failure analysis and IC repair, is capable of cross-sectioning nodular defects. Utilizing the instrument`s scanning on beam, high-resolution imaging of the seeds that initiate nodular defect growth is possible. In an attempt to understand the origins of these seeds, HfO{sub 2}/SiO{sub 2} and Ta{sub 2}O{sub 5}/SiO{sub 2} coatings were prepared by a variety of coating vendors and different deposition process… more
Date: December 29, 1995
Creator: Stolz, C. J.; Tench, R. J.; Kozlowski, M. R. & Fornier, A.
Partner: UNT Libraries Government Documents Department
open access

Enhanced tensile ductility in Al-Mg alloys by solid-solution interactions

Description: The development of methods for obtaining high tensile elongation in aluminum alloys is of great importance for the practical forming of near-net-shape parts. Current superplastic alloys are limited in use by high material costs. The utilization of solute-drag creep processes, the approach used in this study, to obtain enhanced tensile ductility in aluminum alloys has lead to tensile elongations of up to 325% in simple, binary Al-Mg alloys with coarse grain sizes. This method has the advantage o… more
Date: November 29, 1995
Creator: Taleff, E. M.; Henshall, G. A.; Lesuer, D. R.; Nieh, T. G. & Wadsworth, J.
Partner: UNT Libraries Government Documents Department
open access

High-efficiency, dielectric multilayer gratings optimized for manufacturability and laser damage threshold

Description: Ultrashort pulse, high-intensity lasers offer new opportunities for the study of light-matter interaction and for inertial confinement fusion. A 100 Terawatt laser operating 400 fs and 1.053 {mu}m is operational at LLNL, and a 1000 Terawatt (Petawatt) laser will come online in early 1996. These lasers use large-aperture (40 cm and 94 cm diameter, respectively) diffraction gratings to compress the amplified laser pulse. At present, hologrphically produced, gold overcoated photoresist gratings ar… more
Date: November 29, 1995
Creator: Britten, J. A.; Perry, M. D.; Shore, B. W.; Boyd, R. D.; Loomis, G. E. & Chow, R.
Partner: UNT Libraries Government Documents Department
open access

Development and testing of inorganic sorbents made by the internal gelation process for radionuclide and heavy metal separations

Description: The objectives of this task are to develop, prepare, and test microspheres and granular forms of inorganic ion exchangers to remove radionuclides and heavy metals from waste streams occurring at various sites. Several inorganic materials, such as hexacyanoferrates, titanates, phosphates, and oxides have high selectivities and efficiencies for separating and removing radionuclides such as uranium, technetium, cesium, and strontium, and metals such as cobalt, silver, zinc, and zirconium from aque… more
Date: November 29, 1995
Creator: Egan, B. Z.; Collins, J. L.; Anderson, K. K. & Chase, C. W.
Partner: UNT Libraries Government Documents Department
open access

Testing of ITER central solenoid coil insulation in an array

Description: A glass-polyimide insulation system has been proposed by the US team for use in the Central Solenoid (CS) coil of the international Thermonuclear Experimental Reactor (ITER) machine and it is planned to use this system in the CS model coil inner module. The turn insulation will consist of 2 layers of combined prepreg and Kapton. Each layer is 50% overlapped with a butt wrap of prepreg and an overwrap of S glass. The coil layers will be separated by a glass-resin composite and impregnated in a V… more
Date: September 29, 1995
Creator: Jayakumar, R.; Martovetsky, N. N. & Perfect, S. A.
Partner: UNT Libraries Government Documents Department
open access

Hydrogen as a near-term transportation fuel

Description: The health costs associated with urban air pollution are a growing problem faced by all societies. Automobiles burning gasoline and diesel contribute a great deal to this problem. The cost to the United States of imported oil is more than US$50 billion annually. Economic alternatives are being actively sought. Hydrogen fuel, used in an internal combustion engine optimized for maximum efficiency and as part of a hybrid-electric vehicle, will give excellent performance and range (>480 km) with em… more
Date: June 29, 1995
Creator: Schock, R. N.; Berry, G. D.; Smith, J. R. & Rambach, G. D.
Partner: UNT Libraries Government Documents Department
open access

Dymalloy: A composite substrate for high power density electronic components

Description: High power density electronic components such as fast microprocessors and power semiconductors must operate below the maximum rated device junction temperature to ensure reliability. function temperatures are determined by the amount of heat generated and the thermal resistance from junction to the ambient thermal environment. Two of the Largest contributions to this thermal resistance are the die attach interface and the package base. A decrease in these resistances can allow increased compone… more
Date: June 29, 1995
Creator: Kerns, J.A.; Colella, N.J.; Makowiecki, D. & Davidson, H.L.
Partner: UNT Libraries Government Documents Department
open access

Overview of the current spectroscopy effort on the Livermore electron beam ion traps

Description: An overview is given of the current spectroscopic effort on the Livermore electron beam ion trap facilities. The effort focuses on four aspects: spectral line position, line intensity, temporal evolution, and line shape. Examples of line position measurements include studies of the K-shell transitions in heliumlike Kr{sup 34+} and the 2s-2p intrashell transitions in lithiumlike Th{sup 87+} and U{sup 89+}, which provide benchmark values for testing the theory of relativistic and quantum electrod… more
Date: June 29, 1995
Creator: Beiersdorfer, P.; Lopez-Urrutia, J.C. & Brown, G.
Partner: UNT Libraries Government Documents Department
open access

The cryogenic helium cooling system for the Tokamak physics experiment

Description: The Tokamak Physics Experiment (TPX) will use supercritical helium to cool all the magnets and supply helium to the Vacuum cryopumping subsystem. The heat loads will come from the standard steady state conduction and thermal radiation sources and from the pulsed loads of the nuclear and eddy currents caused by the Central Solenoid Coils and the plasma positioning coils. The operations of the TPX will begin with pulses of up to 1000 seconds in duration every 75 minutes. The helium system utilize… more
Date: September 29, 1995
Creator: Felker, Brian; Slack, Donald S. & Wendland, Craig R.
Partner: UNT Libraries Government Documents Department
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