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Time resolution performance studies of contemporary high speed photomultipliers

Description: The time resolution capabilities of prototype microchannel plate and static crossed-field photomultipliers have been investigated. Measurements were made of electron transit time, rise time, time response, single photoelectron time spread and multiphotoelectron time spread for LEP HR350 proximity focused high gain curved microchannel plate and VPM-154A/1.6L static crossed-field photomultipliers. The experimental data have been compared with results obtained with conventionally designed RCS 8850… more
Date: October 5, 1977
Creator: Leskovar, B. & Lo, C.C.
Partner: UNT Libraries Government Documents Department
open access

Cryopumping system for TFTR neutral beam injectors

Description: The cryocondensation pumping system for the TFTR neutral beam injectors is described. Topics include hardware design, differential pumping and beam loss, operational modes, and response to massive vacuum breaks.
Date: October 5, 1977
Creator: Valby, L.E.
Partner: UNT Libraries Government Documents Department
open access

Nickel--chromium strain gages for cryogenic stress analysis of superconducting structures in high magnetic fields

Description: Evaluation and calibration measurements were performed on commercial nickel-chromium metal-foil strain gages in a high-magnetic-field (12 T), liquid-helium (4.2 K) environment. The purpose was to fully characterize strain gages for use at cryogenic temperatures in high magnetic fields. In this study, the magnetoresistance of a number of strain gages was measured in three orthogonal directions at mechanical strain levels to 8900 ..mu..m/m. As a result, a unique calibration curve was defined for … more
Date: October 5, 1977
Creator: Freynik, H.S. Jr.; Roach, D.R.; Deis, D.W. & Hirzel, D.G.
Partner: UNT Libraries Government Documents Department
open access

Strain-critical current data for large multifilament Nb/sub 3/Sn conductors

Description: Strain-critical current measurements of monolithic, multifilament Nb/sub 3/Sn conductors are extended to larger conductors carrying approximately 3.5 kA at 12 T. Measurements were made under pure tension up to 0.9 percent strain and under combined tensile (up to 0.36 percent) and bending (+-0.53 percent) strain. Our results came close to those obtained previously on smaller (1 to 2 kA) conductors. These latest data served as our basis to design a prototype 5-kA, 12-T conductor for a 40-cm-bore … more
Date: October 5, 1977
Creator: Deis, D.W.; Cornish, D.N.; Hirzel, D.G. & Rosdahl, A.R.
Partner: UNT Libraries Government Documents Department
open access

Scintillation and Luminescence Properties of Undoped and Cerium-doped LiGdCl4 and NaGdCl4

Description: We report the scintillation properties of the undoped and cerium-doped variations of LiGdCl4 and NaGdCl4. Powder samples of these materials exhibit significant scintillation under X-rays. The samples were synthesized by solid-state methods from a 1:1 molar ratio of lithium or sodium chloride and gadolinium chloride. Cerium trichloride was used as the dopant. The physical, optical, and scintillation properties of these materials were analyzed by powder X-ray diffraction, photoluminescence, X-ray… more
Date: October 5, 2008
Creator: Porter-Chapman, Yetta D.; Bourret-Courchesne, Edith D.; Bizarri, Gregory; Weber, Marvin J. & Derenzo, Stephen E.
Partner: UNT Libraries Government Documents Department
open access

Pressure-Induced Electronic Spin Transition of Iron in Magnesiow?stite-(Mg,Fe)O

Description: An electronic transition of iron in magnesiowuestite has been studied with synchrotron Moessbauer and X-ray emission spectroscopies under high pressures. Synchrotron Moessbauer studies show that the quadrupole splitting disappears and the isomer shift drops significantly across the spin-paring transition of iron in (Mg{sub 0.75},Fe{sub 0.25})O between 62 and 70 GPa, whereas X-ray emission spectroscopy of the Fe-K{sub {beta}} fluorescence lines in dilute (Mg{sub 0.95},Fe{sub 0.05})O also confirm… more
Date: October 5, 2005
Creator: Lin, J. F.; Gavriliuk, A. G.; Struzhkin, V. V.; Jacobsen, S. D.; Sturhahn, W.; Hu, M. Y. et al.
Partner: UNT Libraries Government Documents Department
open access

Heat-exchanger concepts for neutral-beam calorimeters

Description: Advanced cooling concepts that permit the design of water cooled heat exchangers for use as calorimeters and beam dumps for advanced neutral beam injection systems were evaluated. Water cooling techniques ranging from pool boiling to high pressure, high velocity swirl flow were considered. Preliminary performance tests were carried out with copper, inconel and molybdenum tubes ranging in size from 0.19 to 0.50 in. diameter. Coolant flow configurations included (1) smooth tube/straight flow, (2)… more
Date: October 5, 1981
Creator: Thompson, C.C.; Polk, D.H.; McFarlin, D.J. & Stone, R.
Partner: UNT Libraries Government Documents Department
open access

Leaching characteristics of actinides from simulated reactor waste, Part 2. [Borosilicate glass]

Description: Leach rates for /sup 237/Np and /sup 239/Pu are investigated with a single-pass leaching system. The factorial experimental design uses several combinations of solution composition and flow rate, and two temperatures, 25 and 75/sup 0/C. The 25/sup 0/C results are compared with those from a modified IAEA procedure. At 25/sup 0/C, leach rates decrease with time. Agreement between results from the single-pass and modified IAEA methods is fair with WIPP brine leachant, good with NaHCO/sub 3/, and g… more
Date: October 5, 1979
Creator: Weed, H. C.; Coles, D. G.; Bradley, D. J.; Mensing, R. W.; Schweiger, J. S. & Rego, J. H.
Partner: UNT Libraries Government Documents Department
open access

Feasibility study of a fission supressed blanket for a tandem-mirror hybrid reactor

Description: A study of fission suppressed blankets for the tandem mirror not only showed such blankets to be feasible but also to be safer than fissioning blankets. Such hybrids could produce enough fissile material to support up to 17 light water reactors of the same nuclear power rating. Beryllium was compared to /sup 7/Li for neutron multiplication; both were considered feasible but the blanket with Li produced 20% less fissile fuel per unit of nuclear power in the reactor. The beryllium resource, while… more
Date: October 5, 1981
Creator: Moir, R. W.; Lee, J. D. & Barr, W. L.
Partner: UNT Libraries Government Documents Department
open access

Automatic Ion-Exchange Chromatography in Corrosive Solvent Systems

Description: An automated system for the performance of ion-exchange chromatography with corrosive solvents has been built. It is LSI-II microcomputer controlled and is capable of selecting six sample/solvents and collecting six separate fractions. Preliminary results on the separation of plutonium from 8M HNO/sub 3/ solutions indicate that the system can achieve chemical yields, analytical accuracy, and precision fully comparable to manual column operation at a considerable savings of operator time.
Date: October 5, 1979
Creator: Hosmer, D. W. & Gazlay, A. L.
Partner: UNT Libraries Government Documents Department
open access

Determination of technetium-99 by liquid scintillation counting

Description: A rapid and reliable method for analyzing technetium-99 in a wide variety of environmental samples, including waters, soils, stream sediments, and vegetations, has been developed. The procedure entails oxidizing the technitium to the heptavalent state and dissolving it in 6 N sulfuric acid. From that medium the technetium is quantitatively and selectively extracted into tributyl phosphate. A portion of the extract is then added to a scintillation cocktail, and technetium-99 activity is measured… more
Date: October 5, 1979
Creator: Walker, C. R.; Short, B. W. & Spring, H. S.
Partner: UNT Libraries Government Documents Department
open access

A proposed metric for assessing the potential of community annoyance from wind turbine low-frequency noise emissions

Description: Given our initial experience with the low-frequency, impulsive noise emissions from the MOD-1 wind turbine and their impact on the surrounding community, the ability to assess the potential of interior low-frequency annoyance in homes located near wind turbine installations may be important. Since there are currently no universally accepted metrics or descriptors for low-frequency community annoyance, we performed a limited program using volunteers to see if we could identify a method suitable … more
Date: October 5, 1987
Creator: Kelley, N.D.
Partner: UNT Libraries Government Documents Department
open access

Notification of change in a data base

Description: The Supervisory Control and Diagnostics System for the Mirror Fusion Test Facility is an event driven system; tasks that handle specific events are active only when those events occur. One method of monitoring and generating events is the data base notification facility; a task can request that it be loaded and started by the dbms if a data element is touched or goes outside of a specified range. The motivations for this facility (along with an example of its use and some specifics regarding ho… more
Date: October 5, 1981
Creator: Nelson, B.C.
Partner: UNT Libraries Government Documents Department
open access

TMX-Upgrade neutral-beam injection system

Description: The TMX experiment proved that axial confinement of central-cell ions is improved ninefold by the electrostatic potential of end-cell plasmas. The TMX Upgrade task is to improve this confinement further. This paper discusses the injector system aspects of the TMX Upgrade.
Date: October 5, 1981
Creator: Felker, B.; Kane, R. J.; Wong, R. L.; Calderon, M. O. & Moore, T. L.
Partner: UNT Libraries Government Documents Department
open access

Rotating liquid blanket with no first wall for fusion reactors

Description: A toroidal vortex of liquid FLiBe (LiF + BeF/sub 2/) is suggested for the blanket of a fusion reactor. Because this system has no solid first wall, it might avoid many of the problems that accompany conventional blanket design. The liquid is sustained by nozzles that inject a continuous layer of cool liquid on the inner surface. A second set of nozzles sends a stream of droplets across the diverted scrape-off layer or edge plasma to carry its heat away. The feasibility issues of most importance… more
Date: October 5, 1988
Creator: Moir, Ralph W.
Partner: UNT Libraries Government Documents Department
open access

Reaction cross-section calculations using new experimental and theoretical level structure data for deformed nuclei

Description: A technique for modeling quasiparticle excitation energies and rotational parameters in odd-odd deformed nuclei has been used to construct sets of discrete states with energy 0 to 1.5 MeV in /sup 176/Lu and /sup 236/Np. These data were used as part of the input for calculation of isomer production cross-section ratios in the /sup 175/Lu(n,..gamma..)/sup 176/Lu and /sup 237/Np(n,2n)/sup 236/Np reactions. In order to achieve agreement with experiment, it has been found necessary to include in the… more
Date: October 5, 1984
Creator: Hoff, R. W.; Gardner, D. G. & Gardner, M. A.
Partner: UNT Libraries Government Documents Department
open access

Improved Energy Coupling into the Gain Region of the Ni-Like Pd Transient Collisional X-Ray Laser

Description: We present within this paper a series of experiments, which yield new observations to further our understanding of the transient collisional x-ray laser medium. We use the recently developed technique of picosecond x-ray laser interferometry to probe the plasma conditions in which the x-ray laser is generated and propagates. This yields two dimensional electron density maps of the plasma taken at different times relative to the peak of the 600ps plasma-forming beam. In another experimental camp… more
Date: October 5, 2004
Creator: Smith, R.; Dunn, J.; Filevich, J.; Moon, S.; Nilsen, J.; Keenan, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Objective function for the environmental assessment of waste

Description: Various waste management systems were examined in order to determine what the environmental impacts might be and to rank the relative importance of those impacts. This examination determined that radiation dose to man was the most significant, and probably overriding, impact. This report describes methods of providing an objective function for dose to man. The search for an objective function began with a reading of Federal Regulations and the output of various standard setting councils and com… more
Date: October 5, 1976
Creator: Toy, A. J.; Boegel, J. & Cohen, J. J.
Partner: UNT Libraries Government Documents Department
open access

National Waste Terminal Storage Program

Description: Objective of this program is to provide facilities (Federal repositories) in various deep geologic formations at several locations in USA for the safe disposal of commercial radioactive waste from power reactors. The four types of containerized waste are described. The steps for developing the repositories are outlined. (DLC)
Date: October 5, 1976
Creator: Zerby, C. D.
Partner: UNT Libraries Government Documents Department
open access

Fast Ignition Transport Simulations for NIF

Description: This paper shows work at Lawrence Livermore National Lab (LLNL) devoted to modeling the propagation of, and heating by, a relativistic electron beam in a idealized dense fuel assembly for fast ignition. The implicit particle-in-cell (PIC) code LSP is used. Experiments planned on the National Ignition Facility (NIF) in the next few years using the Advanced Radiography Capability (ARC) short-pulse laser motivate this work. We demonstrate significant improvement in the heating of dense fuel due to… more
Date: October 5, 2009
Creator: Strozzi, D J; Grote, D P; Tabak, M; Cohen, B I; Town, R P & Kemp, A J
Partner: UNT Libraries Government Documents Department
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