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Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

Description: An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
Partner: UNT Libraries Government Documents Department
open access

Assessment of the response of spent fuel transports to malevolent acts

Description: This paper describes the results of a program conducted at Sandia National Laboratories (SNL) for the US Department of Energy to provide an experimental data base for more accurately assessing the radiological consequences from a hypothetical sabotage attack on a spent fuel shipping cask. The primary objectives of the program were limited to: (1) evaluating the effectiveness of selected high explosive devices (HED) in breaching full-size spent fuel casks, (2) quantifying and characterizing rele… more
Date: December 20, 1983
Creator: Sandoval, R.P.
Partner: UNT Libraries Government Documents Department
open access

Materials testing using laser energy deposition

Description: A convenient method for determining the elastic constants of materials has been devised using the energy from a Q-switched neodymium-glass laser. Stress waves are induced in materials having circular rod or rectangular bar geometries by the absorption of energy from the laser. The wave transit times through the material are recorded with a piezoelectric transducer. Both dilatation and shear wave velocities are determined in a single test using an ultrasonic technique and these velocities are us… more
Date: December 20, 1977
Creator: Wilcox, W.W. & Calder, C.A.
Partner: UNT Libraries Government Documents Department
open access

Monopole search using an accelerator detector

Description: A neutrino detector at the Brookhaven AGS has been used to investigate the feasibility of using an already constructed apparatus for GUT monopole searches. A flux limit (90%CL) of 5.2 x 10/sup -12/ cm/sup -2/ sec/sup -1/ str/sup -1/ was found. The limitations of such an approach are discussed.
Date: December 20, 1983
Creator: Ahrenes, L.A.; Aronson, S.H.; Connolly, P.L.; Erickson, T.E.; Gibbard, B.G.; Montag, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Directions for possible upgrades of the Mirror Fusion Test Facility (MFTF)

Description: The Mirror Fusion Test Facility (MFTF) may be upgraded by extending the time of plasma sustenance in an approach to steady-state operation and/or by increasing the neutral-beam injection energy. Some parameter bounds for these upgrades are discussed as they relate to a definition of the required neutral-beam development.
Date: December 20, 1977
Creator: Damm, C. C.; Coensgen, F. H.; Devoto, R. S.; Molvik, A. W.; Porter, G. D.; Shearer, J. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Photocathode transfer and storage techniques using alkali vapor feedback control

Description: Photocathodes of quantum efficiency above 1% at the doubled YAG frequency of 532 nM are very sensitive to the local vacuum environment. These cathodes must have a band gap of less than 2.3 eV, and a work function that is also on the order of {approximately}2 volts or less. As such, these surfaces are very reactive as they provide many surface states for the residual gases that have positive electron affinities such as oxygen and omnipotent water. Attendant to this problem is that the optimal op… more
Date: December 20, 1991
Creator: Springer, R.W. & Cameron, B.J.
Partner: UNT Libraries Government Documents Department
open access

Horizontal gene transfer and the evolution of transcriptionalregulation in Escherichia coli

Description: Background: Most bacterial genes were acquired by horizontalgene transfer from other bacteria instead of being inherited bycontinuous vertical descent from an ancient ancestor}. To understand howthe regulation of these {acquired} genes evolved, we examined theevolutionary histories of transcription factors and of regulatoryinteractions from the model bacterium Escherichia coli K12. Results:Although most transcription factors have paralogs, these usually arose byhorizontal gene transfer rather t… more
Date: December 20, 2007
Creator: Price, Morgan N.; Dehal, Paramvir S. & Arkin, Adam P.
Partner: UNT Libraries Government Documents Department
open access

Control of the Magnetic and Magnetotransport Properties of La0.67Sr0.33MnO3 Thin Films Through Epitaxial Strain

Description: The influence of epitaxial strain, in the form of tetragonal distortions, on the magnetic and magnetotransport properties of La{sub 0.67}Sr{sub 0.33}MnO{sub 3} thin films was studied. The tetragonal distortion (c/a ratio) was modulated through the choice of the substrate, ranging from c/a=1.007 on (001)-oriented (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7} substrates to 0.952 on (110)-oriented GdScO{sub 3} substrates. In agreement with previous theoretical predictions, these large va… more
Date: December 20, 2007
Creator: Arenholz, Elke; Takamura, Y.; Chopdekar, R.V.; Arenholz, E. & Suzuki, Y.
Partner: UNT Libraries Government Documents Department
open access

Bell-Plesset effects for an accelerating interface with contiguous density gradients

Description: A Plesset-type treatment [J. Appl. Phys. 25, 96 (1954)] is used to assess the effects of contiguous density gradients at an accelerating spherical classical interface on Rayleigh-Taylor and Bell-Plesset perturbation growth. Analytic expressions are obtained that describe enhanced Rayleigh-Taylor instability growth from contiguous density gradients aligned with the acceleration and which increase the effective Atwood number of the perturbed interface. A new pathway for geometric amplification of… more
Date: December 20, 2005
Creator: Amendt, P
Partner: UNT Libraries Government Documents Department
open access

Boltzmann babies in the proper time measure

Description: After commenting briefly on the role of the typicality assumption in science, we advocate a phenomenological approach to the cosmological measure problem. Like any other theory, a measure should be simple, general, well defined, and consistent with observation. This allows us to proceed by elimination. As an example, we consider the proper time cutoff on a geodesic congruence. It predicts that typical observers are quantum fluctuations in the early universe, or Boltzmann babies. We sharpen this… more
Date: December 20, 2007
Creator: Bousso, Raphael; Bousso, Raphael; Freivogel, Ben & Yang, I-Sheng
Partner: UNT Libraries Government Documents Department
open access

TEM Study of Fracturing in Spherical and Plate-like LiFePO4Particles

Description: An investigation of fracturing in LiFePO{sub 4} particles as a function of the particle morphology and history is presented. Two types of samples, one subjected to electrochemical cycling and another to chemical delithiation are compared. We observe the formation of micro fractures parallel to low indexed lattice planes in both samples. The fracture surfaces are predominantly parallel to (100) planes in the chemically delithiated powder and (100) and (010) planes in the electrochemically cycled… more
Date: December 20, 2007
Creator: Gabrisch, H.; Wilcox, J. & Doeff, M.M.
Partner: UNT Libraries Government Documents Department
open access

Limitations of science and adaptive management

Description: Adaptive management consists in patterning human sustenancewithin the constraints of Earth and biological systems whose behavior isinherently uncertain and difficult to control. For successful adaptivemanagement, a mind-set recognizing the limitations of science isneeded.
Date: December 20, 2001
Creator: Narasimhan, T.N.
Partner: UNT Libraries Government Documents Department
open access

Recent developments in neutron electric dipole moment and related CP violating quantities

Description: We summarize recent theoretical developments in CP violation related to the neutron electric dipole moment, chromo-electric dipole moments for quarks, chromo-electric dipole moment for gluon, and electric dipole moments for electron and W boson. 31 refs.
Date: December 20, 1990
Creator: Chang, D. (Northwestern Univ., Evanston, IL (USA). Dept. of Physics and Astronomy Fermi National Accelerator Lab., Batavia, IL (USA))
Partner: UNT Libraries Government Documents Department
open access

Adapting an x-ray/debris shield to the cascade ICF power plant: Neutronics issues

Description: A neutronics analysis has been carried out to determine the effects on the Cascade ICF reactor concept of adding a solid-lithium x-ray and debris shield to each ICF capsule. Results indicate that tritium breeding in LiAlO{sub 2} is possible with a modest isotopic enhancement in {sup 6}Li (to 15%). The shallow-burial index is greater than 1 (indicating that deep burial may be required) if the blanket is kept in the reactor for more than 2.5 yr. Nine percent of the total thermal power is unrecove… more
Date: December 20, 1990
Creator: Tobin, M.T.
Partner: UNT Libraries Government Documents Department
open access

Evaluated Rayleigh integrals for pulsed planar expanding ring sources

Description: Time-domain analytic and semianalytic pressure fields acoustically radiated from expanding pulsed ring sources imbedded in a planar rigid baffle have been calculated. The source functions are radially symmetric delta-function distributions whose amplitude and argument have simple functional dependencies on radius and time. Certain cases yield closed analytic results, while others result in elliptic integrals, which are evaluated to high accuracy by Gauss-Chebyshev and modified Gauss-Legendre qu… more
Date: December 20, 1985
Creator: Warshaw, S.I.
Partner: UNT Libraries Government Documents Department
open access

Neutronics analysis for HYLIFE-II

Description: A preliminary neutronics analysis of the HYLIFE-2 reactor concept gives a tritium breeding ratio of 1.17 and a system energy multiplication factor of 1.14. Modified SS-316 (in which Mn is substituted for Ni) is superior to Hastelloy X and Hastelloy N as a firstwall material considering He generation, dpa-limited lifetime, and shallow-burial index. Since Flibe is corrosive to Mn metals, however, a favorable first-wall material is yet to be decided on. Flibe impurities considered (e.g., inherent … more
Date: December 20, 1990
Creator: Tobin, M.T.
Partner: UNT Libraries Government Documents Department
open access

Positron Lifetime Studies of Defect Structures in Ba Sub 1-X K Sub X BiO Sub 3

Description: Temperature-dependent positron lifetime experiments have been performed from room temperature to cryogenic temperatures on Ba{sub 1-x}K{sub x}BiO{sub 3}, for x = 0.4 and 0.5. From the temperature dependence of the positron lifetime in the normal state, we observe a clear signature of competition between separate defect populations to trap the positron. Theoretical calculations of lifetimes of free or trapped positrons have been performed on Ba{sub 1-x}K{sub x}BiO{sub 3}, to help identify these … more
Date: December 20, 1990
Creator: O'Brien, J. C.; Howell, R. H.; Radousky, H. B.; Sterne, P. A.; Hinks, D. G.; Folkerts, T. J. et al.
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of CP violation in gauge theory and the recent developments

Description: Various mechanisms of CP violation in gauge theory are reviewed. We discuss the impact of recent developments associated with electric dipole moment(EDM) of neutron (D{sub n}), EDM of quarks(D{sub q}), chromo-EDM of quarks(D{sub q}{sup c}), chromo-EDM of gluon(D{sub G}{sup c}), EDM of electron(D{sub e}), and EDM of W boson(D{sub W}). 89 refs., 31 figs.
Date: December 20, 1990
Creator: Chang, D. (Northwestern Univ., Evanston, IL (USA). Dept. of Physics and Astronomy)
Partner: UNT Libraries Government Documents Department
open access

Material transfer system in support of the plutonium immobilization program

Description: The Plutonium Immobilization Program requires development of the process and plant prototypic equipment to immobilize surplus plutonium in ceramic for long-term storage. Because of the hazardous nature of plutonium, it was necessary to develop a remotely operable materials transfer system which can function within the confines of a glovebox. In support of this work at LLNL, such a material transfer system (MTS) was developed. This paper presents both the mechanical and controls parts making up … more
Date: December 20, 2000
Creator: Pak, D
Partner: UNT Libraries Government Documents Department
open access

Salient Points for Tracking Moving Objects in Video

Description: Detection and tracking of moving objects is important in the analysis of video data. One approach is to maintain a background model of the scene and subtract it from each frame to detect the moving objects which can then be tracked using Kalman or particle filters. In this paper, we consider simple techniques based on salient points to identify moving objects which are tracked using motion correspondence. We focus on video with a large field of view, such as a traffic intersection with several … more
Date: December 20, 2004
Creator: Kamath, C; Gezahegne, A; Newsam, S & Roberts, G M
Partner: UNT Libraries Government Documents Department
open access

Plasma experiments with 1. 06-. mu. m lasers at the Lawrence Livermore Laboratory

Description: Recent laser fusion experiments at the Lawrence Livermore Laboratory have provided basic data concerning: laser beam propagation and absorption in high temperature plasmas, electron energy transport processes that transfer the absorbed laser energy to the high-density ablation region, the general fluid dynamic expansion and compression of the heated plasma, and the processes responsible for the production of 14-MeV neutrons during implosion experiments. Irradiation experiments were performed wi… more
Date: December 20, 1976
Creator: Ahlstrom, H. G.; Holzrichter, J. F.; Manes, K. R.; Storm, E. K.; Boyle, M. J.; Brooks, K. M. et al.
Partner: UNT Libraries Government Documents Department
open access

A NORMETEX MODEL 15 M3/HR WATER VAPOR PUMPING TEST

Description: Tests were performed using a Model 15 m{sup 3}/hr Normetex vacuum pump to determine if pump performance degraded after pumping a humid gas stream. An air feed stream containing 30% water vapor was introduced into the pump for 365 hours with the outlet pressure of the pump near the condensation conditions of the water. Performance of the pump was tested before and after the water vapor pumping test and indicated no loss in performance of the pump. The pump also appeared to tolerate small amounts… more
Date: December 20, 2010
Creator: Klein, J.; Fowley, M. & Steeper, T.
Partner: UNT Libraries Government Documents Department
open access

Automatic Fault Characterization via Abnormality-Enhanced Classification

Description: Enterprise and high-performance computing systems are growing extremely large and complex, employing hundreds to hundreds of thousands of processors and software/hardware stacks built by many people across many organizations. As the growing scale of these machines increases the frequency of faults, system complexity makes these faults difficult to detect and to diagnose. Current system management techniques, which focus primarily on efficient data access and query mechanisms, require system adm… more
Date: December 20, 2010
Creator: Bronevetsky, G; Laguna, I & de Supinski, B R
Partner: UNT Libraries Government Documents Department
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