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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

Chemiluminescence from the reaction of Ba /sup 3/D with nitric oxide

Description: The reaction of laser excited Ba*(/sup 3/D) states with nitric oxide is presented. BaO product is not detected, although the channel is thermodynamically open, and instead chemiluminescence is observed. Experiments which suggest that radiative recombination, Ba + NO ..-->.. BaNO* ..-->.. BaNO, is the observed reaction channel will also be presented.
Date: January 5, 1977
Creator: Johnson, S. A.; Solarz, R. W.; Dubrin, J. W. & Brotzmann, R.
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

Technology development for high-salinity geothermal resources

Description: An impulse turbine for Total Flow utilization of geothermal fluids was tested. Performance measurements verify the calculational model. The research goal of 70% engine efficiency remains credible. Addition of acid to the brine prevents scaling and precipitation at moderate costs. Corrosion and erosion of turbine materials for the Total Flow Process are not severe. (JB)
Date: August 5, 1977
Creator: Lundberg, A.W.
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

Engineering design of a 40 kV neutral-beam source

Description: Sections of the 40-kV, 40-A, TMX source are shown. This module is comprised of the arc chamber and accelerator sections. The source accelerator section uses a single rectangular insulator to perform three functions: providing voltage standoff, forming the supporting structure, and acting as the vacuum wall. Both machinable glass ceramic (Corning Macor/sup TM/) and F.R.P. (Nema G-10) have been used for this insulater. In either case, the insulator is joined to the titanium base plate and extract… more
Date: November 5, 1979
Creator: Duffy, T. J.; Molvik, A. W.; Baird, E. D.; Correll, D. L.; Munger, R. H.; Gillespie, K. et al.
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

Software for the Local Control and Instrumentation System for MFTF

Description: There are nine different systems requiring over fifty computers in the Local Control and Instrumentation System for the Mirror Fusion Test Facility. Each computer system consists of an LSI-11/2 processor with 32,000 words of memory, a serial driver that implements the CAMAC serial highway protocol. With this large number of systems it is important that as much software as possible be common to all systems. A serial communications system has been developed for data transfers between the LSI-11/2… more
Date: November 5, 1979
Creator: Labiak, W. G.
Partner: UNT Libraries Government Documents Department
open access

Stochastic motion due to a single wave in a magnetoplasma

Description: A single electrostatic wave in a magnetoplasma causes stochastic ion motion in several physically different situations. Various magnetic fields (uniform, tokamak, and mirror) and various propagation angles with respect to the field have been studied. A brief review of this work shows that all situations can be understood using the concept of overlapping resonances. Analytical calculations of the wave amplitude necessary for stochasticity have been carried out in some cases and compared with com… more
Date: June 5, 1979
Creator: Smith, G. R.
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

Water-related impacts of geothermal energy production in California's Imperial Valley

Description: To successfully develop the geothermal resources of the Imperial Valley, adequate supplies of cooling water must be obtained. The primary sources of water include waste waters from agricultural lands, condensate from flashed-steam facilities, and irrigation water. The major advantages and disadvantages of these supplies are examined and then the consequences of adopting six sets of water policies to support three scenarios of geothermal energy production are assessed. The assessment includes an… more
Date: July 5, 1979
Creator: Layton, D. W.
Partner: UNT Libraries Government Documents Department
open access

Applicability of flat plate methods in determining fluid/structure interaction effects in BWR pressure suppression systems

Description: Flat plate chord tests are one experimental method used to investigate how fluid/structure interaction (FSI) effects modify the impulsive loading in nuclear reactor pressure suppression pools. This analytical study examines the applicability of using a flexible flat plate in an otherwise rigid shell to model dynamic pool wall response in a flexible shell pressure suppression torus. Bubble pressures varying by a factor of seven are used as input to two-dimensional finite-element models. Boundary… more
Date: March 5, 1979
Creator: Holman, G.S.; McCauley, E.W. & Lu, S.C.H.
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

Water-cooled U-tube grids for continuously operated neutral-beam injectors

Description: A design for water-cooled extractor grids for long-pulse and continuously operated ion sources for neutral-beam injectors is described. The most serious design problem encountered is that of minimizing the thermal deformation (bowing) of these slender grid rails, which have typical overall spans of 150 mm and diameters on the order of 1 mm. A unique U-tube design is proposed that offers the possibility of keeping the thermal bowing down to about 0.05 mm (about 2.0 mils). However, the design req… more
Date: November 5, 1979
Creator: Hoffman, M. A. & Duffy, T. J.
Partner: UNT Libraries Government Documents Department
open access

Micro-fresnel structures for microscopy of laser generated bright x-ray sources

Description: A brief parametric survey of the x-ray characteristics of a gold micro-disk irradiated at 3 x 10/sup 14/ watt/cm/sup 2/ by a 1 nsec Nd-glass laser pulse has been provided as an example of a laser generated bright x-ray source. It was shown that a simple phenomenological model of the laser generated x-ray source as a microscopic equilibrium plasma radiating as a blackbody for a finite time determined by its hydrodynamic disassembly and radiation losses, serves to provide an adequate approximatio… more
Date: June 5, 1979
Creator: Ceglio, N.M.; Shavers, D.C.; Flanders, D.C. & Smith, H.I.
Partner: UNT Libraries Government Documents Department
open access

Fusion target design

Description: Most detailed fusion target design is done by numerical simulation using large computers. Although numerical simulation is briefly discussed, this lecture deals primarily with the way in which basic physical arguments, driver technology considerations and economical power production requirements are used to guide and augment the simulations. Physics topics discussed include target energetics, preheat, stability and symmetry. A specific design example is discussed.
Date: December 5, 1978
Creator: Bangerter, R.O.
Partner: UNT Libraries Government Documents Department
open access

Nonlinear Behavior of Stimulated Scatter in Large Underdense Plasmas

Description: Several nonlinear effects which limit Brillouin and Raman scatter of intense light in large underdense plasmas are examined. After briefly considering ion trapping and harmonic generation, we focus on the self-consistent ion heating which occurs as an integral part of the Brillouin scattering process. In the long-term nonlinear state, the ion wave amplitude is determined by damping on the heated ion tail which self-consistently forms. A simple model of the scatter is presented and compared with… more
Date: November 5, 1979
Creator: Kruer, W. L. & Estabrook, K. G.
Partner: UNT Libraries Government Documents Department
open access

Emittance measurements on field emitter diodes

Description: On the basis of time-integrated emittance measurements, several different types of field emitter diodes were characterized at 1 to 3 kA, 1 MeV. These measurements were part of the design effort for the injector system of a linear induction accelerator, to be used as a flash x-ray source at Lawrence Livermore Laboratory. The experimental parameters were the cathode type, the anode mesh texture, the diode spacing and voltage, and the level of collimation of the emerging beam. Experimental results… more
Date: April 5, 1979
Creator: Kulke, B. & Kihara, R.
Partner: UNT Libraries Government Documents Department
open access

Corrosion of steel tendons used in prestressed concrete pressure vessels

Description: The purpose of this investigation was to determine the corrosion behavior of a high strength steel (ASTM A416-74 grade 270), typical of those used as tensioning tendons in prestressed concrete pressure vessels, in several corrosive environments and to demonstrate the protection afforded by coating the steel with either of two commercial petroleum-base greases or Portland Cement grout. In addition, the few reported incidents of prestressing steel failures in concrete pressure vessels used for co… more
Date: December 5, 1978
Creator: Griess, J. C. & Naus, D. J.
Partner: UNT Libraries Government Documents Department
open access

Filter fluorescer experiment on the Argus laser

Description: A filter fluorescer experiment has been installed and operated on the Argus laser system of the Lawrence Livermore Laboratory. X-ray spectra have been measured between 20 and 116 keV from laser produced plasmas. Three spectral cuts were made in this region (20 to 29, 47 to 61 and 80 to 116 keV) with an additional channel providing a measure of the high energy response (> 116 keV) of the third channel. We have measured x-ray spectra from laser shots of 600 to 900 J in 1 ns with intensities of 3 … more
Date: September 5, 1978
Creator: Kornblum, H.N.; Pruett, B.L.; Tirsell, K.G. & Slivinsky, V.M.
Partner: UNT Libraries Government Documents Department
open access

Fluorescence diagnostics in two-step laser excitation of high J atoms

Description: Using a pair of lasers near 6000 A, the J = 6 ground state is excited to a J = 6 intermediate level and then to a J = 5 upper state. Non-resonant fluorescences from both excited states are separately detected. Results of a set of model calculations are tabulated. Level 3 average populations are always very small, since the system decays rapidly into inaccessible metastable states. This means that chemistry experiments are difficult. The differences between parallel and perpendicular polarizatio… more
Date: April 5, 1979
Creator: Stern, Richard C.; Shore, Bruce W. & Lang, Neil C.
Partner: UNT Libraries Government Documents Department
open access

Ignition inhibitors for cellulosic materials. [Fire retardants; effects of irradiation]

Description: By exposing samples to various irradiance levels from a calibrated thermal radiation source, the ignition responses of blackened alpha-cellulose and cotton cloth with and without fire-retardant additives were compared. Samples treated with retardant compounds which showed the most promise were then isothermally pyrolyzed in air for comparisons between the pyrolysis rates. Alpha-cellulose samples containing a mixture of boric acid, borax, and ammonium di-hydrogen phosphate could not be ignited b… more
Date: April 5, 1976
Creator: Alvares, N. J.
Partner: UNT Libraries Government Documents Department
open access

EPMT: a portable transfer standard for telemetry system pressure-transducer calibration

Description: The LLL developed electronic pressure meter (EPMT) is a portable static-pressure calibration instrument for use with the LLL telemetry transducer system at the Nevada Test Site (NTS). It is significantly more accurate and rugged than the bourdon-tube pressure gauge it replaces, and can be incorporated into a field-use, semi-automatic, pressure calibration system. The process by which a transducer is selected for EPMT use from the inventory of field-service-certified transducers and subjected to… more
Date: April 5, 1977
Creator: Hasbrouck, Richard T.
Partner: UNT Libraries Government Documents Department
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