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High-Voltage Power Supply System for Laser Isotope Separation

Description: This report presents several concepts for Laser High-Voltage Power Supply (HVPS) Systems for a Laser Isotope Separation facility. Selection of equipments and their arrangement into operational systems is based on proven designs and on application concepts now being developed. This report has identified a number of alternative system arrangements and has provided preliminary cost estimates for each. The report includes a recommendation for follow-on studies that will further define the optimum L… more
Date: June 26, 1979
Creator: Ketaily, E.C.; Buckner, R.P. & Uhrik, R.L.
Partner: UNT Libraries Government Documents Department
open access

Detailed Comparison of Blast Effects in Air and Vacuum

Description: Although blast mitigation is most often achieved with solid shielding, ambient gas pressure can also affect the coupling of shock waves to solid targets. In this work the role of air as an energy transfer medium was examined experimentally by subjecting identical large-area rectangular witness plates to short-range blast effects in air and vacuum ({approx}50 mtorr) at 25 C. The expanding reactant front of 3 kg C4 charges was observed by fast camera to be cylindrically symmetric in both air and … more
Date: July 26, 2007
Creator: Tringe, J W; Molitoris, J D; Garza, R G; Andreski, H G; Batteux, J D; Lauderbach, L M et al.
Partner: UNT Libraries Government Documents Department
open access

Image Resolution in Scanning Transmission Electron Microscopy

Description: Digital images captured with electron microscopes are corrupted by two fundamental effects: shot noise resulting from electron counting statistics and blur resulting from the nonzero width of the focused electron beam. The generic problem of computationally undoing these effects is called image reconstruction and for decades has proved to be one of the most challenging and important problems in imaging science. This proposal concerned the application of the Pixon method, the highest-performance… more
Date: June 26, 2008
Creator: Pennycook, S. J. & Lupini, A.R.
Partner: UNT Libraries Government Documents Department
open access

Fast Prediction of HCCI and PCCI Combustion with an Artificial Neural Network-Based Chemical Kinetic Model

Description: We have added the capability to look at in-cylinder fuel distributions using a previously developed ignition model within a fluid mechanics code (KIVA3V) that uses an artificial neural network (ANN) to predict ignition (The combined code: KIVA3V-ANN). KIVA3V-ANN was originally developed and validated for analysis of Homogeneous Charge Compression Ignition (HCCI) combustion, but it is also applicable to the more difficult problem of Premixed Charge Compression Ignition (PCCI) combustion. PCCI co… more
Date: September 26, 2007
Creator: Piggott, W. T.; Aceves, S. M.; Flowers, D. L. & Chen, J. Y.
Partner: UNT Libraries Government Documents Department
open access

Threshold Studies on TNT, Composition B, and C-4 Explosives Using the Steven Impact Test

Description: Steven Impact Tests were performed at low velocity on the explosives TNT, Comp B, and C-4 in attempts to obtain a threshold for reaction. A 76 mm helium driven gas gun was used to accelerate the Steven Test projectiles up to approximately 200 m/s in attempts to react (ignite) the explosive samples. Blast overpressure gauges, acoustic microphones, standard video and high-speed photography were used to characterize the level of any high explosive reaction violence. No bulk reactions were observed… more
Date: September 26, 2005
Creator: Vandersall, K S; Switzer, L L & Garcia, F
Partner: UNT Libraries Government Documents Department
open access

Calibration of Chemical Kinetic Models Using Simulations of Small-Scale Cookoff Experiments

Description: Establishing safe handling limits for explosives in elevated temperature environments is a difficult problem that often requires extensive simulation. The largest influence on predicting thermal cookoff safety lies in the chemical kinetic model used in these simulations, and these kinetic model reaction sequences often contain multiple steps. Several small-scale cookoff experiments, notably Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), One-Dimensional Time-to-Explos… more
Date: February 26, 2008
Creator: Wemhoff, A P; Becker, R C & Burnham, A K
Partner: UNT Libraries Government Documents Department
open access

Nondestructive, energy-dispersive, x-ray fluorescence analysis of product stream concentrations from reprocessed nuclear fuels

Description: Energy-dispersive x-ray fluorescence analysis (XRFA) can be used to measure nondestructively pure and mixed U/Pu concentrations in process streams and hold tank solutions. The 122-keV gamma ray from /sup 57/Co excites the actinide K x rays which are detected by a HPGe detector. A computer- and disk-based analyzer system provides capability for making on-stream analyses, and the noninvasive measurement is easily adapted directly to appropriate sized pipes used in a chemical reprocessing plant. M… more
Date: November 26, 1979
Creator: Camp, D. C. & Ruhter, W. D.
Partner: UNT Libraries Government Documents Department
open access

Determination of Fe(II)Fe(II) ratio in glass

Description: The procedure was designed for the simple, rapid determination of the Fe(II)/Fe(III) ratio in glass samples. The procedure consists of the following steps: dissolution of the pulverized glass sample in a sulfuric-hydrofluoric acid mixture, containing ammonium vanadate, which preserves the Fe(II) content; addition of boric acid to destroy iron-fluoride complexes, making the iron available for color formation with Ferrozine; addition of pH 5 buffer and Ferrozine reagent to form the magenta-colore… more
Date: July 26, 1989
Creator: Baumann, E. W.
Partner: UNT Libraries Government Documents Department
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Remote measurements of actinide species in aqueous solutions using an optical fiber photoacoustic spectrometer

Description: A photoacoustic spectrometer, equipped with an 85 meter optical fiber, was used to perform absorption measurements of lanthanide and actinide samples, located in a glovebox. The spectrometer was tested using aqueous solutions of praseodymium and americium ions; the sensitivity for remote measurements was found to be similar to that achieved in the laboratory without the fiber. 14 refs., 3 figs.
Date: September 26, 1990
Creator: Russo, R. E. (Lawrence Berkeley Lab., CA (United States)); Robouch, P. B. & Silva, R. J. (Lawrence Livermore National Lab., CA (United States))
Partner: UNT Libraries Government Documents Department
open access

Direct aromatization of methane. Quarterly technical progress report No. 3, April 1, 1993--June 30, 1993

Description: Construction of quench-reactor has been completed. Gaseous reactants are fed in a downward flow and the quenching medium (water) pumped upward into a concentric reactor housed in a high temperature (1540C) furnace. The furnace has a 24 inch, resistively-heated zone, with an overall length of 38 inches. The gaseous effluent is sampled directly into a gas chromatograph via a sampling valve. The gas chromatographic procedure for analysis of expected products is being developed. Several columns hav… more
Date: September 26, 1992
Partner: UNT Libraries Government Documents Department
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Low energy ion-molecule reactions and chemiionization kinetics. Progress report, February 1, 1991--January 31, 1994

Description: Work over the past 3 years was directed toward the dynamics of elementary gas phase proton transfer reactions, particularly those of the O{sup {minus}} ion. Such reactions are important in flames. Published work over the past 30 months was concerned with dynamics of reactions of O{sup {minus}} with H{sub 2}O, NH{sub 3}, and HF. Results are enumerated here.
Date: July 26, 1993
Creator: Farrar, J. M.
Partner: UNT Libraries Government Documents Department
open access

Acenaphthene solvents for use in Building 313 Frost Test operation

Description: Acenaphtheno is a low-melting organic compound, C{sub 10}H{sub 6}(CH{sub 2}){sub 2}, used as a temperature indicating coating for slugs tested in the Frost Test induction coil. In preparation for this test, slugs are coated by spraying a 12 to 24 per cent by weight solution of acenaphthene in a high vapor pressure solvent on the rotating slug. The solvent evaporate leaving a thin, adherent coating of acenaphthene. This process is completely described in reference 1. To be entirely satisfactory … more
Date: June 26, 1951
Creator: Kratzer, W. K.
Partner: UNT Libraries Government Documents Department
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Tritium monitor and collection system

Description: This system measures tritium on-line and collects tritium from a flowing inert gas stream. It separates the tritium from other non-hydrogen isotope contaminating gases, whether radioactive or not. The collecting portion of the system is constructed of various zirconium alloys called getters. These alloys adsorb tritium in any of its forms at one temperature and at a higher temperature release it as a gas. The system consists of four on-line getters and heaters, two ion chamber detectors, two co… more
Date: March 26, 1991
Creator: Baker, J. D.; Wickham, K. L.; Ely, W. E.; Tuggle, D. G.; Meikrantz, D. H.; Grafwaller, E. G. et al.
Partner: UNT Libraries Government Documents Department
open access

Chemistry of coal-related microparticles. Quarterly report, March 1, 1992--May 31, 1992

Description: This research project involves the study of coal macerals and sorbent microparticles used to remove S0{sub 2} and/or H{sub 2}S from process streams. To measure reaction rates a charged single microparticle will be held electrodynamically in one or more laser beams by superposed ac and dc electrical fields. The use of the electrodynamic balance for microparticle studies was pioneered by one of the principal investigators. One of the laser beams is used for light-scattering measurements to determ… more
Date: May 26, 1992
Creator: Davis, J. E. & Krieger-Brockett, B.
Partner: UNT Libraries Government Documents Department
open access

Final Technical Report on DE-SC00002460 [Bimetallic or trimetallic materials with structural metal centers based on Mn, Fe or V]

Description: Bimetallic or trimetallic materials with structural metal centers based on Mn, Fe or V were investigated under this project. These metal centers are the focus of this research as they have high earth abundance and have each shown success as cathode materials in lithium batteries. Silver ion, Ag{sup +}, was initially selected as the displacement material as reduction of this center should result in increased conductivity as Ag{sup 0} metal particles are formed in-situ upon electrochemical reduct… more
Date: July 26, 2013
Creator: Takeuchi, Esther Sans; Takeuchi, Kenneth James & Marschilok, Amy Catherine
Partner: UNT Libraries Government Documents Department
open access

Final Technical Report for DOE Grant, number DE-FG02-05ER15701; Probing Surface Chemistry Under Catalytic Conditions: Olefin Hydrogenation,Cyclization and Functionalization.

Description: The specific goal of this work was to understanding the catalytic reactions pathways for the synthesis of vinyl acetate over Pd, Au and PdAu alloys. A combination of both experimental methods (X-ray and Auger spectroscopies, low-energy ion scattering (LEIS), low-energy electron diffraction (LEED) and theory (Density Functional Theory (DFT) calculations and Monte Carlo methods under various different reactions) were used to track the surface chemistry and the influence of alloying. The surface i… more
Date: May 26, 2011
Creator: Neurock, Matthew
Partner: UNT Libraries Government Documents Department
open access

RESPONSE OF ALUMINUM SPHERES IN SITU TO DETONATION

Description: Time sequence x-ray imaging was utilized to determine the response of aluminum spheres embedded in a detonating high-explosive cylinder. The size of these spheres ranged from 3/8-inch to 1/32-inch in diameter. These experiments directly observed the response of the spheres as a function of time after interaction with the detonation wave. As the spheres are entrained in the post-detonation flow field, they are accelerating and their velocity profile is complicated, but can be determined from the… more
Date: March 26, 2010
Creator: Molitoris, J D; Garza, R G; Tringe, J W; Batteux, J D; Wong, B M; Villafana, R J et al.
Partner: UNT Libraries Government Documents Department
open access

Chemistry of coal-related microparticles

Description: This research project involves the study of coal macerals and sorbent microparticles used to remove S0{sub 2} and/or H{sub 2}S from process streams. To measure reaction rates a charged single microparticle will be held electrodynamically in one or more laser beams by superposed ac and dc electrical fields. The use of the electrodynamic balance for microparticle studies was pioneered by one of the principal investigators. One of the laser beams is used for light-scattering measurements to determ… more
Date: May 26, 1992
Creator: Davis, J. E. & Krieger-Brockett, B.
Partner: UNT Libraries Government Documents Department
open access

Calibration of energy dispersive x-ray spectrometers for analysis of thin environmental samples

Description: Four separate techniques for calibrating energy dispersive x-ray spectrometers are described. They include the use of (1) individual evaporated elemental thin-film standards, (2) nebulized multielement standard solution deposits to determine relative elemental sensitivity factors, (3) a semi-empirical approach to calculate relative elemental sensitivity factors, and (4) thick pure element disks. The first three techniques are applicable for a broad range of elements. The utilization of nebulize… more
Date: January 26, 1976
Creator: Giauque, R. D.; Garrett, R. B. & Goda, L. Y.
Partner: UNT Libraries Government Documents Department
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Studies of factors affecting uranium determinations by automated coulometric titration (New Brunswick Laboratory/Davies--Gray Method)

Description: The method's errors are defined to ascertain its absolute accuracy. An analytical technique was developed to examine vanadyl sulfate diluent for vanadium (V). None could be found in any of the lots tested. Certain lots of reagent-grade phosphoric acid contained an unidentified impurity that caused high generator-electrode potentials and a positive error. The current-potential characteristics of the generator electrode were measured. The data indicated that a significant fraction of uranium (IV)… more
Date: April 26, 1976
Creator: Harrar, J. E. & Boyle, W. G.
Partner: UNT Libraries Government Documents Department
open access

Method to prepare Semtex

Description: This procedure requires the binder and uncoated RDX be prepared in separate steps, see Figure 1: (1) The binder and dye are mixed by agitation with a water-insoluble organic solvent (e.g., toluene), I; (2) The RDX/PETN is agitated thoroughly with water, II; (3) The binder solution I is added to the RDX/water mixture at II with thorough mixing to form a slurry III; (4) In the next step the solvent is distilled off at IV leaving resulting granules; (5) The next step is followed by filtration at V… more
Date: November 26, 2006
Creator: Alcaraz, A. & Dougan, A.
Partner: UNT Libraries Government Documents Department
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