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Impulsive ion acceleration in earth's outer magnetosphere

Description: Considerable observational evidence is found that ions are accelerated to high energies in the outer magnetosphere during geomagnetic disturbances. The acceleration often appears to be quite impulsive causing temporally brief (10's of seconds), very intense bursts of ions in the distant plasma sheet as well as in the near-tail region. These ion bursts extend in energy from 10's of keV to over 1 MeV and are closely associated with substorm expansive phase onsets. Although the very energetic ions… more
Date: January 1, 1985
Creator: Baker, D.N. & Belian, R.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF A PROCESS FOR SODIUM BONDING OF EBR-II FUEL AND BLANKET ELEMENTS

Description: Procedures for assembling EBR-II fuel elements with annular sodium bonds between the uranium rods and the stainless steel claddings are outlined. The results of several meltdown and uranium-settling experiments are given. Bonding experiments were performed: furnace bonding, submerged canning, ultrasonic bonding, centrifuging, pressure pulsing, and vibratory bonding. Vibratory bonding was chosen for the production of the first EBR-II core. (D.L.C.)
Date: July 1, 1961
Creator: Sowa, E.S. & Kimont, E.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mass Transfer Coefficients and Interfacial Area in a One Stage Pulse Column

Description: Over-all mass transfer coefficients were determined independently of the interfacial area by considering the operation of the pulse column to be a stage- wise process. The calculated coefficients describe only the operation of the pulse column for the free rise of organic droplets through a stage, since in the downstroke the aqueous phase passes through the organic phase in the form of rivulets preferentially wetting the plates. The driving force for transfer was based on the aqueous phase conc… more
Date: November 1, 1960
Creator: Konopik, A. E. & Burkhart, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron induced current pulses in fission chambers. [LMFBR]

Description: The mechanism of neutron induced current pulse generation in fission chambers is discussed. By application of the calculated detector transfer function to proposed detector current pulse shapes, and by comparison with actually observed detector output voltage pulses, a credible, semi-empirical, trapezoidal pulse shape of chamber current is obtained.
Date: January 1, 1978
Creator: Taboas, A.L. & Buck, W.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical Technology Division, Unit Operations Section Monthly Progress Report, May 1961

Description: The experimental results on the oxidation of H from a He stream with CuO pellets were very close to the predicted behavior based on the mathematical model. Experimental measurements of uranyl sulfate loading rates on chloride equilibrated resin showed little variation with solution concentrations. A tentative flowsbeet was proposed for cost analysis of processing a Pebble Bed Reactor. A U-Zr plate was dissolved in nitrate-free Zirflex solution. An authentic TRIGA prototype was processed in engi… more
Date: December 26, 1961
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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STUDIES OF THE SCINTILLATION PROCESS IN CsI(Tl)

Description: The scintillation response of CsI(Tl) crystals, having various thallium contents, was measured for excitation of the crystals by monoenergetic gamma rays, protons, and alpha particles. The investi gation was made to provide a test of some of the features of a theoretical model of the scintillation process in thallium-activated alkali iodides proposed by Murray and Meyer. In order to insure that the results obtained in this program would provide a critical test of the scintillation model, specia… more
Date: November 30, 1962
Creator: Gwin, R. & Murray, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some general properties of stimulated Raman propagation with pump depletion, transiency and dispersion

Description: This note considers some of the properties of the Stokes pulse that grows from a specified seed pulse in the presence of a strong pump pulse as it propagates through a dispersive atomic vapor. We first present an generic dimensionless form for the coupled equations that govern the propagation of pump and Stokes fields or collinear plane-wave pulses. By treating the two fields we permit pump depletion. We include transient atomic response (as embodied in the Raman coherence), but neglect changes… more
Date: August 2, 1991
Creator: Shore, B. W.; Lowder, S. & Johnson, M. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Fresh-Bunch' technique in FELs

Description: The 'Fresh Bunch' technique is being proposed as a method of increasing the gain and power of FEL amplifiers in which the length of the optical radiation pulse is shorter than the length of the electron bunch. In multi-stage FEL, electron beam energy spread is increased by the FEL interaction in the early stages. In the 'Fresh Bunch' technique, the low energy spread of the electron beam is recovered by shifting the radiation pulse to an undisturbed part of the electron bunch, thus improving the… more
Date: January 1, 1991
Creator: Ben-Zvi, Ilan; Yang, K. M. & Yu, L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Noise Considerations in Nuclear Pulse Amplifiers

Description: The effects of certain pulse-shaping networks on the signal-to-noise ratio of a nuclear pulse amplifier were considered. The shaping networks discussed are: equal RC-integrating and RC-differentiating time constant, single- delay-line clipper and RC integrator, and doubledelay-line clipper and RC integrator. The effects of these networks on the signal, when high count rates and overload pulses are present, were also considered. Equations and curves were developed for the energy resolution (sign… more
Date: December 20, 1961
Creator: Landis, D. A.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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High-field bipolar loss measurement apparatus

Description: An apparatus was constructed to measure dissipation in superconducting wire in high alternating fields. The apparatus will be used to make measurements on conductors which must operate in fields up to 7.0 T and rates of field change up to 15 T/s. The magnet for this facility is wound of uninsulated, 15 strand Rutherford cable in which the strand is a 0.812 mm diameter, fully mixed matrix, Cu plus CuNi, multifilament NbTi conductor. The coil is wound in a bath cooled configuration with an overal… more
Date: January 1, 1980
Creator: Thullen, P.; Weldon, D. & Wollan, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Research for Electric Energy Systems

Description: This report documents the technical progress in investigations. The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of biological field effects. NIST cohosted a workshop on exposure and biological parameters that should be considered during the vitro studies with extremely low frequency (ELF) magnetic and electric fields. Also, equations were developed to predict the magnetic field in a parallel plate magnetic field expos… more
Date: June 1, 1991
Creator: Anderson, W.E. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Focus wave modes in homogeneous Maxwell's equation - TE-mode

Description: Mathematical formulations are presented for TE-mode, three-dimensional, solitary electromagnetic pulses propagating in free space. The pulses are required to satisfy the homogeneous Maxwell's equations, have a three-dimensional pulse structure, have no charge, move at light velocity in straight lines, have nondispersive pulses for all time, and have finite electromagnetic energy. (LEW)
Date: January 1, 1982
Creator: Brittingham, J.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Enhanced lower hybrid penetration via intense multi-microsecond pulses

Description: Applying lower-hybrid power in short, intense pulses can overcome Landau damping, allowing penetration into the core of reactor-grade plasmas. We present theoretical description of the absorption which accounts for transient collisional effects as well as nonlinear broadening of the resonant plateau. We show results from ray-tracing calculations which include the nonlinear absorption. We also derive the conditions required for pump depletion by parametric instabilities, and assess density deple… more
Date: January 1, 1991
Creator: Cohen, R. H.; Rognlien, T. D. (Lawrence Livermore National Lab., CA (United States)); Bonoli, P. T. & Porkolab, M. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemical Processing Technology Quarterly Progress Report, January-March 1961

Description: Studies are reported on aqueous zirconium processing, dissolution of BeO- UO/sub 2/ ceramic fuel, the aqueous stainless steel process, the behavior of dibutyl phosphates, use of boron (boric acid) solution to assure critical safety, fluidized bed calcination, conversion of amorphous alumina to alpha alumina, the Demonstrational Waste Calcining Facility, removal of long-lived radioisotopes from waste solutions, separation of iron, nickel, and chromiun from stainless steel waste solutions, electr… more
Date: October 31, 1962
Creator: Bower, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A STUDY OF THE SHIELD OF THE UNIVERSITY OF ILLINOIS TRIGA MARK II RESEARCH REACTOR

Description: Detailed measurements were made of the fast-neutron and gamma dose rates and the thermal-neutron fluxes existing at the surfaces of the biological shield of the University of Illinois TRIGA Mark II Research Reactor. Dose rates and fluxes were found to be extremely low. A comparison was made by means of threshold foil techniques between the fast-neutron flux in a beam hole of the reactor during steady-state operation at 1 kw and during a nominal 250 Mw, 30 msec pulse produced by rapid insertion … more
Date: April 23, 1962
Creator: Blosser, T.V.; Freestone, R.M. Jr. & Miller, J.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Lead acid battery pulse discharge investigation. Final report

Description: The effects of high current pulses caused by electric vehicle silicon-controlled rectifier and transistor chopper controllers on battery energy, lifetime, and microstructure were studied. Test equipment and results are described. It was found that the energy of improved golf cart-type batteries deteriorated under pulsed conditions by about 10% with respect to dc conditions for pulses between 16 and 333 Hz - no difference was noted above 333 Hz. Frequencies and duty cycles characteristic of elec… more
Date: April 1, 1980
Creator: Dowgiallo, E
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AIRBLAST OVERPRESSURE AND DYNAMIC PRESSURE OVER VARIOUS SURFACES

Description: Static overpressure and dynamic pressure versus time over surfaces processing different physical properties were measured on two tower shots, 6 and 12. On Shot 12, three surfaces were provided: the natural desert, a water surface consisting of a flooded area, and an asphalt surface. On Shot 6, desert and asphalt areas only were available. There were 123 channels of instrumentation installed for Shot 12, and 24 for Shot 6. From the data, a system of wave-form classification was devised for overp… more
Date: September 11, 1957
Creator: Sachs, D. C.; Swift, L. M. & Sauer, F. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical Technology Division Unit Operations Section Monthly Progress Report, April 1962

Description: Bubble size measurements in the foam column showed that a spinnerette with 50 mu holes gave a nearly normal distribution of bubbles sizes while a coarse fritted glass gas sparger had a tail of large bubbles which did not fit the normal curve. A set of equations solvable by a finite difference technique are presented which completely describe the irreversible reaction rate of H/sub 2/ or CO with a fixed bed of CuO pellets. Radiation damage tests are in progress to evaluate plastics for the Trans… more
Date: October 1, 1962
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A PULSED EDDY CURRENT TEST SYSTEM USING REFLECTED FIELDS

Description: An eddy current test system is described in which the test information is detected as a series of fields reflected from the metal surface and interior. Pulsed electromagnetic fields are caused to impinge upon the test specimen. These fields are restricted to a small cross sectional area over a path in space long enough to be useful for test purposes by devices called mask-apenture assemblies. This approach provides a number of advantages over conventional eddy current methods of comparable capa… more
Date: June 11, 1962
Creator: Renken, C. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Anion Exchange in a Large-Scale Agitated Bed

Description: An agitated ion exchange column was adapted for use in a large radiochemical separations plant. Tests with nonradioactive solutions showed that ion exchange resin could be charged to and discharged from the column through typical plant piping and without the use of mechanical valves. With the agitator turning, the bed passed solutions containing 400 ppm of finely divided silica whereas a fixed bed became plugged. The pressure drop through the column and the absorption characteristics of an anio… more
Date: September 1, 1961
Creator: Caracciolo, V. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Determination of the composition of ordered Pt/sub 3/Co by atom-probe field-ion microscopy: intrinsic problems

Description: Atom-probe field-ion microscope (FIM) analyses were performed on specimens of fully ordered Pt/sub 3/Co. The purpose of the investigation was to study the effects of different important experimental variables on the composition measured by the atom probe technique. The dependence of the alloy's composition on the following variables was determined: (1) pulse fraction (f); (2) specimen temperature; (3) crystal plane; and (4) field-evaporation rate. It was demonstrated that the composition determ… more
Date: May 1, 1980
Creator: Yamamoto, M. & Seidman, D. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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