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Calibration of a neutron log in partially saturated media IV: effects of sonde-wall gap

Description: A gap between a neutron sonde and the wall of a borehole can have a significant effect on the observed count rate. This effect was determined experimentally to be linear with gaps as large as 2.5 cm. The count rate is given by N/sub N/ = K/sub 0/ + K/sub 1/g where K/sub 0/ is the count rate that would be observed at zero gap, and g is the gap. The parameters K/sub 0/ and K/sub 1/ are dependent on both water (ie. hydrogen) content and bulk density. In many situations failure to correct the count… more
Date: March 8, 1984
Creator: Axelrod, M. C. & Hearst, J. R.
Partner: UNT Libraries Government Documents Department
open access

Numerical Modeling of CO2 Sequestration in Geologic Formations - Recent Results and Open Challenges

Description: Rising atmospheric concentrations of CO2, and their role inglobal warming, have prompted efforts to reduce emissions of CO2 fromburning of fossil fuels. An attractive mitigation option underconsideration in many countries is the injection of CO2 from stationarysources, such as fossil-fueled power plants, into deep, stable geologicformations, where it would be stored and kept out of the atmosphere fortime periods of hundreds to thousands of years or more. Potentialgeologic storage reservoirs inc… more
Date: March 8, 2006
Creator: Pruess, Karsten
Partner: UNT Libraries Government Documents Department
open access

Laboratory Measurements of 3 --> 2 X-ray Line Ratios of F-like Fe XVIII and Ni XX

Description: The intensity ratios of 3 {yields} 2 emission lines of Fe XVIII and Ni XX were measured on the Livermore electron beam ion trap (EBIT-I) with a flat-field grating spectrometer. The results were compared with distorted-wave (DW) calculations obtained with the Flexible Atomic Code and recent close-coupling calculations using the R-matrix code. The measured 3s {yields} 2p/3d {yields} 2p ratios are about 20-40% higher than the theoretical values. When more extended configuration interaction is incl… more
Date: March 8, 2007
Creator: Gu, M F; Chen, H; Brown, G V; Beiersdorfer, P & Kahn, S M
Partner: UNT Libraries Government Documents Department
open access

Intensity-based signal separation algorithm for accuratequantification of clustered centrosomes in tissue sections

Description: Centrosomes are small organelles that organize the mitoticspindle during cell division and are also involved in cell shape andpolarity. Within epithelial tumors, such as breast cancer, and somehematological tumors, centrosome abnormalities (CA) are common, occurearly in disease etiology, and correlate with chromosomal instability anddisease stage. In situ quantification of CA by optical microscopy ishampered by overlap and clustering of these organelles, which appear asfocal structures. CA has … more
Date: March 8, 2006
Creator: Fleisch, Markus C.; Maxell, Christopher A.; Kuper, Claudia K.; Brown, Erika T.; Parvin, Bahram; Barcellos-Hoff, Mary-Helen et al.
Partner: UNT Libraries Government Documents Department
open access

X-ray absorption study of the electronic structure of Mn-doped amorphous Si

Description: The electronic structure of Mn in amorphous Si (a-Mn{sub x}Si{sub 1?x}) is studied by X-ray absorption spectroscopy at the Mn L{sub 3,2} edges for x = 0.005-0.18. Except the x = 0.005 sample, which shows a slight signature of Mn{sup 2+} atomic multiplets associated with a local Mn moment, all samples have broad and featureless L{sub 3,2} absorption peaks, corresponding to an itinerant state for all 3d electrons. The broad X-ray absorption spectra exclude the possibility of a localized 3d moment… more
Date: March 8, 2008
Creator: Arenholz, Elke; Zeng, Li; Huegel, A.; Helgren, E.; Hellman, F.; Piamonteze, C. et al.
Partner: UNT Libraries Government Documents Department
open access

First principles calculations of the effect of Pt on NiAl surfaceenergy and the site preference of Pt

Description: Pt-modified NiAl is widely used as a coating material in industry. In this study, the surface energies of NiAl with and without Pt are investigated using first-principles calculations. The presence of Pt in NiAl takes the surface electronic states to higher energies, resulting in an increased surface energy, which explains some of the beneficial effects of Pt on the oxidation resistance of NiAl. The electronic structure of NiAl-Pt alloys is also analyzed in terms of the site preference of Pt in… more
Date: March 8, 2007
Creator: Yu, Rong & Hou, Peggy Y.
Partner: UNT Libraries Government Documents Department
open access

Cryogenic Neutron Spectrometer Development

Description: Cryogenic microcalorimeter detectors operating at temperatures around {approx}0.1 K have been developed for the last two decades, driven mostly by the need for ultra-high energy resolution (<0.1%) in X-ray astrophysics and dark matter searches [1]. The Advanced Detector Group at Lawrence Livermore National Laboratory has developed different cryogenic detector technologies for applications ranging from X-ray astrophysics to nuclear science and non-proliferation. In particular, we have adapted… more
Date: March 8, 2006
Creator: Niedermayr, T.; Hau, I. D.; Friedrich, S.; Burger, A.; Roy, U. N. & Bell, Z. W.
Partner: UNT Libraries Government Documents Department
open access

Experimental study of radium partitioning between anorthite and melt at 1 atm

Description: We present the first experimental radium mineral/melt partitioning data, specifically between anorthite and a CMAS melt at atmospheric pressure. Ion microprobe measurement of coexisting anorthite and glass phases produces a molar D{sub Ra} = 0.040 {+-} 0.006 and D{sub Ra}/D{sub Ba} = 0.23 {+-} 0.05 at 1400 C. Our results indicate that lattice strain partitioning models fit the divalent (Ca, Sr, Ba, Ra) partition coefficient data of this study well, supporting previous work on crustal melting an… more
Date: March 8, 2007
Creator: Miller, S.; Burnett, D.; Asimow, P.; Phinney, D. & Hutcheon, I.
Partner: UNT Libraries Government Documents Department
open access

Electroweak symmetry breaking studies at the pp colliders of the 1990's and beyond

Description: Within the conventional framework of a spontaneously broken gauge theory, general principles establish that the electroweak symmetry is broken by a new force that may be weak with associated new quanta below 1 TeV or strong with quanta above 1 TeV. The SSC parameters, ..sqrt..s = 40 TeV and L = 10/sup 33/ cm/sup /minus/2/s/sup /minus/1/, define a minimal facility with assured capability to observe the signals of symmetry breaking by a strong force above 1 TeV. Foreseeable luminosity upgrades wo… more
Date: March 8, 1989
Creator: Chanowitz, Michael S.
Partner: UNT Libraries Government Documents Department
open access

AP190L and PDP-KI10: a hardware/software measurement report. [FIVE package for use with AP]

Description: This report discusses an AP190L array processor (manufactured by Floating Point Systems of Beaverton, Oregon) interfaced to a PDP-10 (Digital Equipment Corporation, Maynard, Mass.). After AP software installation, an analysis of the overhead was performed. The results of these measurements and some conclusions are presented. An AP monitor and software interface were written to minimize the overhead from the PDP-10. A vector extension to the FORTRAN language called FIVE was developed to increase… more
Date: March 8, 1979
Creator: Maron, N. & Sutherland, G.G.
Partner: UNT Libraries Government Documents Department
open access

Vibrational soliton: an experimental overview

Description: To date the most convincing evidence of vibrational solitons in biopolymers has been found in two very disparate systems: Davydov-like excitations in hydrogen-bonded linear chains (acetanilide and N-methylacetamide) which are not biopolymers but plausible structural paradigms for biopolymers, and longitudinal accoustic modes of possibly nonlinear character in biologically viable DNA. 17 refs., 4 figs.
Date: March 8, 1986
Creator: Bigio, I.J.
Partner: UNT Libraries Government Documents Department
open access

Defining the role of risk assessment in the comprehensive environmental response compensation and liability act remedial investigation process at the DOE-OR

Description: Cleanup of hazardous waste sites under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) is a complicated and painstaking process, particularly at facilities with a multitude of individual hazardous waste sites, each having a multitude of chemicals and radonuclides. The US Department of Energy-Oak Ridge, Environmental Restoration Division (DOE-OR/ERD) administers five such facilities which are undergoing environmental cleanup under the CERCLA Remedial Investigat… more
Date: March 8, 1994
Creator: Miller, P. D.; McGinn, C. W.; White, R. K.; Purucker, S. T. & Redfearn, A.
Partner: UNT Libraries Government Documents Department
open access

Occupied and unoccupied orbitals of C{sub 60} and C{sub 70}

Description: The full spectrum of occupied and unoccupied {sigma} and {pi} orbitals is presented for solid C{sub 60}, C{sub 70}, and graphite, using Cls emission and absorption spectroscopy. There are significant differences between C{sub 60} and C{sub 70}, and even larger changes relative to their infinite analog graphite C{sub {infinity}}. A comparison is made with photoemission and inverse photoemission results, along with first principles quasiparticle calculations.
Date: March 8, 1994
Creator: Carlisle, J. A.; Terminello, L. J. & Hudson, E. S.
Partner: UNT Libraries Government Documents Department
open access

Defect diffusion during annealing of low-energy ion-implanted silicon

Description: We present a new approach for investigating the kinetics of defect migration during annealing of low-energy, ion-implanted silicon, employing a combination of computer simulations and atomic-resolution tunneling microscopy. Using atomically-clean Si(111)-7x7 as a sink for bulk point defects created by 5 keV Xe and Ar irradiation, we observe distinct, temperature-dependent surface arrival rates for vacancies and interstitials. A combination of simulation tools provides a detailed description of … more
Date: March 8, 2000
Creator: Bedrossian, P J; Caturla, M-J & Diaz de la Rubia, T
Partner: UNT Libraries Government Documents Department
open access

2012 MULTIPHOTON PROCESSES GRC, JUNE 3-8, 2012

Description: The sessions will focus on:  Attosecond science;  Strong-field processes in molecules and solids;  Generation of harmonics and attosecond pulses;  Free-electron laser experiments and theory;  Ultrafast imaging;  Applications of very high intensity lasers;  Propagation of intense laser fields.
Date: March 8, 2012
Creator: Walker, Barry
Partner: UNT Libraries Government Documents Department
open access

On Variational Methods in the Physics of Plasma Waves

Description: A fi rst-principle variational approach to adiabatic collisionless plasma waves is described. The focus is made on one-dimensional electrostatic oscillations, including phase-mixed electron plasma waves (EPW) with trapped particles, such as Bernstein-Greene-Kruskal modes. The well known Whitham's theory is extended by an explicit calculation of the EPW Lagrangian, which is related to the oscillation-center energies of individual particles in a periodic fi eld, and those are found by a quad… more
Date: March 8, 2013
Creator: Dodin, I.Y.
Partner: UNT Libraries Government Documents Department
open access

RHIC IR Quadrupoles and Field Quality State of the Art in Super Conducting Accelerator Magnets

Description: The interaction region (IR) quadrupoles [1] for the Relativistic Heavy Ion Collider (RHIC)[2]are the best field quality superconducting magnets ever built for any major accelerator. This field quality is primarily achieved with the help of eight tuning shims [3] that remove the residual errors from a magnet after it is built and tested. These shims overcome the limitations from the typical tolerances in parts and manufacturing. This paper describes the tuning shims and discusses the evolution o… more
Date: March 8, 1999
Creator: Gupta, R.; Anerella, M.; Cozzolino, J.; Ghosh, A.; Jain, A.; Kahn, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Ni spin switching induced by magnetic frustration in FeMn/Ni/Cu(001)

Description: Epitaxially grown FeMn/Ni/Cu(001) films are investigated by Photoemission Electron Microscopy and Magneto-Optic Kerr Effect. We find that as the FeMn overlayer changes from paramagnetic to antiferromagnetic state, it could switch the ferromagnetic Ni spin direction from out-of-plane to in-plane direction of the film. This phenomenon reveals a new mechanism of creating magnetic anisotropy and is attributed to the out-of-plane spin frustration at the FeMn-Ni interface.
Date: March 8, 2009
Creator: Wu, J.; Choi, J.; Scholl, A.; Doran, A.; Arenholz, E.; Hwang, Chanyong et al.
Partner: UNT Libraries Government Documents Department
open access

An Improved Reaction Rate Equation for Simulating the Ignition and Growth of Reaction in High Explosives

Description: We describe an improved reaction rate equation for simulating ignition and growth of reaction in high explosives. It has been implemented into CALE and ALE3D as an alternate to the baseline the Lee-Tarver reactive flow model. The reactive flow model treats the explosive in two phases (unreacted/reactants and reacted/products) with a reaction rate equation to determine the fraction reacted, F. The improved rate equation has fewer parameters, is continuous with continuous derivative, results in a… more
Date: March 8, 2010
Creator: Murphy, M J
Partner: UNT Libraries Government Documents Department
open access

Deflagration Rate Measurements of Three Insensitive High Explosives: LLM-105, TATB, and DAAF

Description: The pressure dependent deflagration rates of LLM-105, DAAF and TATB based formulations were measured in the LLNL high pressure strand burner. The role of binder amount, explosive type, and thermal damage and their effects on the deflagration rate will be discussed. One DAAF formulation, two different formulations of LLM-105, and four formulations of TATB were studied; results indicate that binder amount and type play a minor role in the deflagration behavior. This is in sharp contrast to the HM… more
Date: March 8, 2010
Creator: Glascoe, E A; Maienschein, J L; Lorenz, K T; Tan, N & Koerner, J G
Partner: UNT Libraries Government Documents Department
open access

THERMAL MODELING ANALYSIS OF SRS 70 TON CASK

Description: The primary objective of this work was to perform the thermal calculations to evaluate the Material Test Reactor (MTR) fuel assembly temperatures inside the SRS 70-Ton Cask loaded with various bundle powers. MTR fuel consists of HFBR, MURR, MIT, and NIST. The MURR fuel was used to develop a bounding case since it is the fuel with the highest heat load. The results will be provided for technical input for the SRS 70 Ton Cask Onsite Safety Assessment. The calculation results show that for the SRS… more
Date: March 8, 2011
Creator: Lee, S.; Jordan, J. & Hensel, S.
Partner: UNT Libraries Government Documents Department
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