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The three-point function as a probe of models for large-scale structure

Description: The authors analyze the consequences of models of structure formation for higher-order (n-point) galaxy correlation functions in the mildly non-linear regime. Several variations of the standard [Omega] = 1 cold dark matter model with scale-invariant primordial perturbations have recently been introduced to obtain more power on large scales, R[sub p] [approximately]20 h[sup [minus]1] Mpc, e.g., low-matter-density (non-zero cosmological constant) models, [open quote]tilted[close quote] primordial… more
Date: June 19, 1993
Creator: Frieman, J.A. (Fermi National Accelerator Lab., Batavia, IL (United States)) & Gaztanaga, E. (Univ. of Oxford (United Kingdom))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[Transformation toughening]

Description: In NiAl, we have succeeded in determining the complete Ginzburg-Landau strain free energy function necessary to model the cubic to tetragonal martensite transformation in a sample of any size. We believe that this is the first time that the parameters of a Ginzburg-Landau functional and the complete strain spinodal for any three-dimensional displacive transformation were used in simulating the transformation near a crack tip under Mode I loading; the transformation pattern and toughening are di… more
Date: April 19, 1993
Creator: Rafa, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Midpoint technical report

Description: The research covers high-resolution imaging of electrical conductivity using low-frequency electromagnetic fields. This report contains two appendices: progress made in optimizing a 3D integral equations forward modeling code for imaging, and a technique for improving the resolution of the inverse problem.
Date: April 19, 1993
Creator: Tripp, A. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Laser flash photolysis, EPR and raman studies of liquids at elevated pressures. Progress report, April 1, 1993--November 19, 1993

Description: A laser flash photolysis kinetic study of a W(CO){sub 5} intermediate reacting with several different substituted 2,2{prime}-bipyridine ligands at pressures up to 150 MPa in liquid toluene has confirmed the considerable influence of steric hindrance on the mechanism of a thermal ring closure reaction. A similar laser flash photolysis kinetic study has been carried out with Mo(CO){sub 6} and several bidentate ligands resembling 2,2{prime}-bipyridine dissolved in supercritical carbon dioxide. A m… more
Date: November 19, 1993
Creator: Eyring, E. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of boron and hydrogen on the electronic structure of Ni{sub 3}Al

Description: Using first-principles electronic structure calculations based on the Linear-Muffin-Tin Orbital (LMTO) method, we have investigated the effects of interstitial born and hydrogen on the electronic structure of the Ll{sub 2} ordered intermetallic Ni{sub 3}Al. When it occupies an octahedral interstitial site entirely coordinated by six Ni atoms, we find that boron enhances the charge distribution found in the strongly-bound ``pure`` Ni{sub 3}Al crystal: Charge is depleted at Ni and Al region. Subs… more
Date: November 19, 1993
Creator: Kioussi, N.; Watanabe, H.; Hemker, R. G.; Gourdin, W.: Gonis, A. & Johnson, P. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Midpoint technical report

Description: The research covers high-resolution imaging of electrical conductivity using low-frequency electromagnetic fields. This report contains two appendices: progress made in optimizing a 3D integral equations forward modeling code for imaging, and a technique for improving the resolution of the inverse problem.
Date: April 19, 1993
Creator: Tripp, A. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

[Transformation toughening]. Annual progress report

Description: In NiAl, we have succeeded in determining the complete Ginzburg-Landau strain free energy function necessary to model the cubic to tetragonal martensite transformation in a sample of any size. We believe that this is the first time that the parameters of a Ginzburg-Landau functional and the complete strain spinodal for any three-dimensional displacive transformation were used in simulating the transformation near a crack tip under Mode I loading; the transformation pattern and toughening are di… more
Date: April 19, 1993
Creator: Rafa, M. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Integrated low emissions cleanup system for direct coal fueled turbines (moving bed, fluid bed contactor/ceramic filter). Twenty-third quarterly status report, April--June 1993

Description: The United States Department of Energy, Morgantown Energy Research Center (DOE/METC), is sponsoring the development of direct coal-fired turbine power plants as part of their Heat Engines program. A major technical challenge remaining for the development of the direct coal-fired turbine is high-temperature combustion gas cleaning to meet environmental standards for sulfur oxides and particulate emissions, as well as to provide acceptable turbine life. The Westinghouse Electric Corporation, Scie… more
Date: July 19, 1993
Creator: Newby, R. A.; Alvin, M. A.; Bachovchin, D. M.; Yang, W. C.; Smeltzer, E. E. & Lippert, T. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

X-ray laser `` oscillator-amplifier`` experiments

Description: We present results from experiments directed toward increasing the degree of transverse coherence in x-ray laser beams. We have concentrated on the neon-like yttrium (Z=39) collisionally-pumped x-ray laser as the test system for these studies because of its unique combination of brightness, monochromaticity, and high-reflectivity optics availability. Attempts at improving laser performance using proximate feedback optics failed. Modest success has been found to date in ``double foil`` experimen… more
Date: March 19, 1993
Creator: Shimkaveg, G. M.; Carter, M. R.; Young, B. K. F.; Walling, R. S.; Osterheld, A. L.; Trebes, J. E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Control of pyrite surface chemistry in physical coal cleaning. Final report

Description: In Part I, Surface Chemistry of Coal Pyrite the mechanisms responsible for the inefficient rejection of coal pyrite were investigated using a number of experimental techniques. The test results demonstrate that the hydrophobicity of coal pyrite is related to the surface products formed during oxidation in aqueous solutions. During oxidation, a sulfur-rich surface layer is produced in near neutral pH solutions. This surface layer is composed mainly of sulfur species in the form of an iron-polysu… more
Date: May 19, 1993
Creator: Luttrell, G. H.; Yoon, R. H. & Richardson, P. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Weak neutral currents and collapse initiated supernova

Description: Since 1974 the neutrino processes mediated by neutral currents have been a part of supernova (SN) modeling calculations. In this report only present day SN calculations will be discussed. First I will give brief description of the SN computer model and an outline of the explosion process as depicted by that model. Then I will discuss the role weak neutral current (WNC) processes play in this explosion process. Finally, I will discus inelastic scattering of tau neutrinos by heavy elements in WNC… more
Date: March 19, 1993
Creator: Wilson, J. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The three-point function as a probe of models for large-scale structure

Description: The authors analyze the consequences of models of structure formation for higher-order (n-point) galaxy correlation functions in the mildly non-linear regime. Several variations of the standard {Omega} = 1 cold dark matter model with scale-invariant primordial perturbations have recently been introduced to obtain more power on large scales, R{sub p} {approximately}20 h{sup {minus}1} Mpc, e.g., low-matter-density (non-zero cosmological constant) models, {open_quote}tilted{close_quote} primordial… more
Date: June 19, 1993
Creator: Frieman, J. A. & Gaztanaga, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Older muons are wiser: Using time information in {mu}LCR spectroscopy

Description: For {mu}LCR with slow polarization transfer, the weak resonance signals can be strengthened by delaying the positron observation period, for pulsed and chopped muon beams. Furthermore, the sensitivity to drifts can be reduced or eliminated by using the ratios of late to early e{sup +} counts. These possibilities for using time information are discussed quantitatively.
Date: May 19, 1993
Creator: Leon, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A lower cost development path for heavy ion fusion

Description: If two features of the inertial fusion process are exploited successfully, they can lead to significantly lower costs for demonstrating the feasibility of commercial electric power production from this source of energy. First, fusion capsule ignition and burn physics is independent of reaction chamber size and hydrodynamically-equivalent capsules can be designed to perform at small yield, exactly as they do at large yield. This means that an integrated test of all power plant components and fea… more
Date: May 19, 1993
Creator: Hogan, W. J. & Meier, W. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advanced, soluble hydroliquefaction and hydrotreating catalysts. Quarterly reports No. 10 and 11, January 1, 1993--May 30, 1993

Description: The purpose of the present program is to develop soluble analogs of surface confined catalysts that can be impregnated directly into the coal structure at low temperatures. This approach should avoid problems related to surface area dependence, a two phase (surface-liquid) reaction system and, mass transport limitations. Heteropolyanions (HPAs) offer the opportunity to develop soluble forms of surface confined catalysts. HPAs, are inexpensive, well-characterized, water soluble metal oxide clust… more
Date: May 19, 1993
Creator: Laine, R. M. & Stoebe, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling the response of ecosystems to CO{sub 2} and climate change. Progress report, September 1, 1992--June 19, 1993

Description: In recognition of the role of plants in the bio-geosphere carbon cycle, the Department of Energy (OHER) initiated a research program: The Direct Effects of Increasing Carbon Dioxide on Vegetation. This report describes the continuing research that we are conducting as part of this program. The ultimate goal of our research is to develop computer models capable of predicting responses of plants and ecosystems to the direct and indirect effects of atmospheric levels of carbon dioxide that are app… more
Date: June 19, 1993
Creator: Reynolds, J. F.; Kemp, P. R. & Chen, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The effects of in-situ processing methods on the microstructure and fracture toughness of V-V{sub 3}Si composites

Description: This paper describes ductile-phase roughening in V-V{sub 3}Si in-situ composites produced by conventional arc melting (AM), cold-crucible induction melting (IM), and cold-crucible directional solidification (DS). Notched three-point bending tests were performed to determine the effects of synthesis method on the room temperature fracture toughness of eutectic compositions, which contain nearly equal volume fractions of V{sub 3}Si and the V(Si) solid solution phase. Fracture toughness values ran… more
Date: November 19, 1993
Creator: Strum, M. J.; Henshall, G. A.; Bewlay, B. P.; Sutliff, J. A. & Jackson, M. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Mercury: The Los Alamos ICF KrF laser system

Description: The Mercury KrF laser facility at Los Alamos is being built with the benefit of lessons learned from the Aurora system. An increased understanding of KrF laser engineering, and the designed implementation of system flexibility, will permit Mercury to serve as a tested for a variety of advanced KrF technology concepts.
Date: January 19, 1993
Creator: Czuchlewski, S. J.; York, G. W.; Bigio, I. J.; Brucker, J.; Hanson, D.; Honig, E. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Uranium purchases report 1992

Description: Data reported by domestic nuclear utility companies in their responses to the 1991 and 1992 ``Uranium Industry Annual Survey,`` Form EIA-858, Schedule B ``Uranium Marketing Activities,are provided in response to the requirements in the Energy Policy Act 1992. Data on utility uranium purchases and imports are shown on Table 1. Utility enrichment feed deliveries and secondary market acquisitions of uranium equivalent of US DOE separative work units are shown on Table 2. Appendix A contains a list… more
Date: August 19, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Observation of nonsequential ionization of helium and its impact on intensity monitoring

Description: The authors have measured the ion yields for helium and neon ionized by 120 femtosecond, 614 nanometer laser pulses with intensities up to 10{sup 16} watts per square centimeter. They have found that the He II and Ne II data exhibit features incompatible with standard nonresonant sequential ionization. These features reduce the usefulness of optical field ionization for monitoring laser intensity. For the experiment, they expect dynamic resonances to have little effect on the ionization, and th… more
Date: March 19, 1993
Creator: Fittinghoff, D. N.; Bolton, P. R.; Chang, B. & Kulander, K. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Production of dense vapor targets for laser-plasma interaction studies with intense, ultra-short pulses

Description: The technique of laser-induced ablation of thin films from glass slide substrates has been investigated as a candidate vapor target production method for studies of both tunneling-driven x-ray/xuv recombination lasers and relativistic propagation using intense, ultra-short laser pulses. It is shown by simultaneous two-wavelength interferometry that particle densities of order 10{sup 19}/cm{sup 3} are readily achieved and that some intrinsic ionization accompanies the plume formation. Absorption… more
Date: March 19, 1993
Creator: Bolton, P. R.; Eder, D. C.; Guethlein, G.; Stewart, R. E. & Young, P. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A mobile remote sensing laboratory for water vapor, trace gas, aerosol, and wind speed measurements

Description: The Lawrence Livermore National Laboratory has developed a mobile field laboratory for remote measurement of atmospheric processes and observables that are important in global climate change, dispersal of hazardous materials, and atmospheric pollution. Specific observables of interest are water vapor, trace gases, aerosol size and density, wind, and temperature. The goal is to study atmospheric processes continuously for extended periods in remote field locations. This laboratory has just reach… more
Date: March 19, 1993
Creator: Slaughter, D.; White, W.; Tulloch, W. & DeSlover, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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