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Wavelength dependence and efficiency of laser heating of DT-filled polymer-coated glass microspheres at cryogenic temperatures

Description: We have determined experimentally the fraction of laser light incident on DT filled cryogenic polymer coated and bare glass microsphere targets that is absorbed to produce target heating. Data have been obtained for bare glass and CH and CF polymer coated microspheres at 488 nm and 632 nm laser wavelengths. The measurement technique used and experimental results obtained are presented.
Date: September 24, 1981
Creator: Darling, D.H.; Bernat, T.P. & Ives, B.H.
Partner: UNT Libraries Government Documents Department
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Theoretical studies on the electronic structure and properties of complex ceramic crystals and glasses

Description: This progress report summarizes the accomplishment of the DOE-support research program at the University of Missouri-Kansas City for the period July 1, 1991--June 30, 1992. This is the second year of a three-year renewal. The major accomplishments for the year are: (a) Initiation of fundamental studies on the electronic properties of C{sub 60} and related crystals; (b) study of electronic structures and optical properties of several important ceramic crystals, especially on AlN, SiO{sub 2} and Al{sub 2}O{sub 3}; (c) first-principles calculation of total energies and structural phase transitions in oxides, nitrides, and borides; (d) theory of magnetism in Nd{sub 2}Fe{sub 14}B permanent magnetic alloy. The major focus for the next year's effort will be on the following areas: (1) Continuation of the fundamental studies on the buckminsterfullerene system with particular emphasis on the alkali-doped superconducting fullerides. (2) Fundamental studies on the structure and properties of Boron and B-related compounds. (3) Basic studies on the structural and electronic properties of metallic glasses with particular emphasis on the magnetic glasses. (4) Further development of the first-principles OLCAO method for applications to super-complex systems.
Date: January 24, 1991
Creator: Ching, Wai-Yim.
Partner: UNT Libraries Government Documents Department
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Laser-Generated Shockwave Experiments at Extreme High Pressures

Description: The application of high-power lasers to production of extreme high pressures is discussed. Shock velocities consistent with pressures up to 2 TPa in aluminum have already been measured, and experiments in the 4 TPa range are now planned. We describe the status of our programs to develop new diagnostic techniques and perform experiments to characterize perturbing influences on the shock.
Date: July 24, 1979
Creator: Trainor, R. J.; Holmes, N. C. & More, R. M.
Partner: UNT Libraries Government Documents Department
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Seismic analysis of the LOFT Diesel Generator ''A'' Cooling System

Description: A static equivalent seismic analysis of the Diesel Generator ''A'' Cooling System has been completed. The static equivalent loads were applied to the radiator, over-pressure tank, piping, and the pipe supports. The cooling system was found to be structurally adequate for the applied SSE loading. 2 refs., 2 figs.
Date: March 24, 1978
Creator: Finicle, D.P.
Partner: UNT Libraries Government Documents Department

Quadrula mortoni, Specimen #1088

Description: One preserved mussel specimen including the left valve only. The specimen exhibits a round shape; moderately thick shell; white internal coloring; brown external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 0 - 60 mm in length and was assessed to be long dead when collected.
Date: October 24, 1973
Creator: Pettit, J.
Partner: Elm Fork Natural Heritage Museum
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Focus Group Report: New York University - New York City - September, 2005

Description: This report is part of the Web-at-Risk project. This report includes the following three sections: (a) the methodology used to conduct the focus groups and analyze the data, (b) the detailed results of the analysis organized into phases of the collection development process, and (c) a discussion of the key findings.
Date: March 24, 2006
Creator: Murray, Kathleen R. & Hsieh, Inga K.
Partner: UNT Libraries
open access

The effect of the light round-trip time on the performance of an adaptive optics turbulence compensation system

Description: The propagation of a laser beam through atmospheric turbulence can, under many circumstances, be compensated to near diffraction limited levels, by use of an adaptive optics system. In the ideal case, a beacon light source is generated at the aimpoint. This light traverses through the turbulent path back to the aperture. The distribution of phase perturbations in the aperture plane is sensed, and the reverse of this phase is applied to the outgoing beam. When the turbulent path is long (i.e. a few hundred kilometers), and the effective wind speed is high (such as in the case when the laser is based on a plane, with airspeeds around 200 m/s), the performance of the adaptive optics system can be significantly degraded due to the time delay from when the beacon samples the turbulence, until the beam propagates through the turbulence. This effect has not been treated in the past, because for astronomical applications, the time delays due to the round trip of light are too short (tens of microseconds) to cause problems. This paper presents an analysis of the anisoplanatic effect of the round trip time of light. A formulation of the phase variance has been constructed for this effect. The time response of the adaptive optics system (i.e. servo bandwidth) is intimately related to the light round trip time effect, and is included in the analysis. Results are first obtained for the large aperture limit, and then the effects of finite aperture size are treated. A set of scaling relationships have been found that enable the formulation to be cast in a form that is insensitive to the turbulence strength profile along the propagation path.
Date: February 24, 1992
Creator: Stroud, P.
Partner: UNT Libraries Government Documents Department
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Relativistic nuclear fluid dynamics and VUU kinetic theory

Description: Relativistic kinetic theory may be used to understand hot dense hadronic matter. We address the questions of collective flow and pion production in a 3 D relativistic fluid dynamic model and in the VUU microscopic theory. The GSI/LBL collective flow and pion data point to a stiff equation of state. The effect of the nuclear equation of state on the thermodynamic parameters is discussed. The properties of dense hot hadronic matter are studied in Au + Au collisions from 0.1 to 10 GeV/nucleon. 22 refs., 5 figs.
Date: August 24, 1987
Creator: Molitoris, J.J.; Hahn, D.; Alonso, C.; Collazo, I.; D'Alessandris, P.; McAbee, T. et al.
Partner: UNT Libraries Government Documents Department
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Resonances in near-threshold x-ray photoabsorption of inner shells

Description: Synchrotron radiation measurements of near-threshold and broad-range (20 eV - 3 keV) absolute photoabsorption cross sections were made at the Brookhaven National Laboratory (NSLS) and at Stanford (SSRL). Transmission data for well-characterized multilayer foils provided absolute cross sections with 10% overall uncertainties and better than 0.2% energy resolution. Several examples of our results are presented.
Date: August 24, 1987
Creator: Del Grande, N.K.; Tirsell, K.G.; Schneider, M.B.; Garrett, R.F.; Kneedler, E.M. & Manson, S.T.
Partner: UNT Libraries Government Documents Department
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Decay properties of nuclei at the end of the periodic system

Description: Recent studies of nuclear mass models show that it is essential to account for the Coulomb redistribution energy when calculating the nuclear potential energy in the heavy-element region. Results obtained by use of a mass model that includes Coulomb redistribution effects on analyzed. Q values of {alpha} and {beta} decay are calculated. Half-lives for {alpha} decay are estimated by use of the Viola-Seaborg systematics. For EC, {beta}{sup +} decay and {beta}{sup {minus}} decay, half-lives are calculated in a microscopic QRPA model. Calculated single-particle level structures in the heavy-element regions are presented. These indicate possible regions of isomers that would be unusually stable with respect to spontaneous fission and {alpha} decay. Finally, we discuss the implications of earlier extensive work on fission properties of nuclei in this region.
Date: January 24, 1992
Creator: Moeller, P. (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)) & Nix, J.R. (Los Alamos National Lab., NM (United States))
Partner: UNT Libraries Government Documents Department
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SPH (smoothed particle hydrodynamics) simulations of hypervelocity impacts

Description: The smoothed particle hydrodynamics (SPH) method has been used to simulate several cases of hypervelocity impact in an exploratory study to determine the suitability of the method for such problems. The calculations compare favorably with experimental results and with other numerical simulations. We discuss the requirements that must be satisfied for SPH to produce accurate simulations of such problems. 18 refs., 9 figs.
Date: January 24, 1991
Creator: Cloutman, L.D.
Partner: UNT Libraries Government Documents Department
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Enhanced Waste Tank Level Model

Description: 'With the increased sensitivity of waste-level measurements in the H-Area Tanks and with periods of isolation, when no mass transfer occurred for certain tanks, waste-level changes have been recorded with are unexplained.'
Date: June 24, 1999
Creator: Duignan, M.R.
Partner: UNT Libraries Government Documents Department
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Janus Upgrade using brewster angle disk amplifier technology. [Janus laser system]

Description: The Nuclear Test and Experimental Science Program (NTES) has requested that the Laser Program design and price an upgrade to the Janus laser system (JANUS UPGRADE) capable of reliably delivering in excess of 200 joules per beamline in a range of pulse forms to three experiment areas. The facility is to have the following characteristics: three experiment areas, two high energy beams, each with 200--400 joule/1 ns at a wavelength of 1.053 or 1.064 microns, and 125--250 J/1 ns when frequency doubled, one probe beam (0.1 J rated at 30 ps) to be used for interferometry, and reliable operation. The proposed facility would occupy approximately 5600 ft{sup 2} and be located in the Bldg. 174 complex. A block diagram of the entire facility is shown in Fig. 1. The facility is further defined by the Work Breakdown Structure (also shown in Fig. 1). The main elements of the WBS are the conventional facility and modifications thereof (WBS 1), special equipment (WBS 2), the laser (WBS 3), the experiment areas (WBS 4), the controls and data acquisition system (WBS 5), and the project integration (WBS 6). The experiment area has three target chambers and uses diagnostic hardware now in Janus. 12 figs., 4 tabs.
Date: October 24, 1990
Creator: Hunt, J.; Boben, R.; Blocker, R.; Clark, J.; Henesian, M.; Victoria, J. et al.
Partner: UNT Libraries Government Documents Department
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Imports from North Korea: Existing Rules, Implications of the KORUS FTA, and the Kaesong Industrial Complex

Description: This report examines the issue of U.S. imports from North Korea in three parts: U.S. rules and practices governing imports from North Korea. North Korea's exports to South Korea (via the KIC) and China, its dominant export markets. The KORUS FTA's potential effect on U.S. imports of North Korean content.
Date: May 24, 2011
Creator: Manyin, Mark E.; Grimmett, Jeanne J.; Jones, Vivian C. & Nanto, Dick K.
Partner: UNT Libraries Government Documents Department
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Corrosion of delta plutonium by synthetic sea water

Description: Tests have been performed to determine the corrosive nature of sea water on delta plutonium at 25/sup 0/C. Corrosion rates were determined by measuring the time dependence of mass loss at constant pressure and the time dependence of hydrogen evolution in a sealed vessel. Test coupons were completely immersed in a standard solution of synthetic sea water for periods ranging from 1 hour to 144 hours. Weight loss measurements show that delta plutonium corrodes at an average rate of 5.01 mg/(cm/sup 2/ hr) while hydrogen is formed at an average rate of 1.6 x 10/sup -5/ mol/(cm/sup 2/ hr). The corrosion process is a hydrolysis reaction that produces hydrated plutonium(IV) oxide and hydrogen. The reaction apparently occurs along the grain boundaries of the metal.
Date: October 24, 1979
Creator: Hodges, III, A. E. & Haschke, J. M.
Partner: UNT Libraries Government Documents Department
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Technical Papers of the Thirteenth Metallographic Group Meeting, Held January 14 and 15, 1959, at Armour Research Foundation of Illinois Institute of Technology, Chicago, Illinois

Description: A total of seven papers is presented. Separate abstracts have been prepared for five papers; the other papers were abstracted previously in NSA. (R.J.S.)
Date: January 24, 1962
Creator: Roth, H. P.
Partner: UNT Libraries Government Documents Department
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