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Absolute instrumental neutron activation analysis at Lawrence Livermore Laboratory

Description: The Environmental Science Division at Lawrence Livermore Laboratory has in use a system of absolute Instrumental Neutron Activation Analysis (INAA). Basically, absolute INAA is dependent upon the absolute measurement of the disintegration rates of the nuclides produced by neutron capture. From such disintegration rate data, the amount of the target element present in the irradiated sample is calculated by dividing the observed disintegration rate for each nuclide by the expected value for the d… more
Date: December 21, 1977
Creator: Heft, R.E.
Partner: UNT Libraries Government Documents Department
open access

Adapting MARSSIM for FUSRAP site closure.

Description: The Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) provides a coherent, technically defensible process for establishing that exposed surfaces satisfy site cleanup requirements. Unfortunately, many sites have complications that challenge a direct application of MARSSIM. Example complications include Record of Decision (ROD) requirements that are not MARSSIM-friendly, the potential for subsurface contamination, and incomplete characterization information. These types of com… more
Date: December 21, 2001
Creator: Johnson, R.; Durham, L.; Rieman, C. & Hoover, R.
Partner: UNT Libraries Government Documents Department
open access

ANDY: A general, fault-tolerant tool for database searching oncomputer clusters

Description: Summary: ANDY (seArch coordination aND analYsis) is a set ofPerl programs and modules for distributing large biological databasesearches, and in general any sequence of commands, across the nodes of aLinux computer cluster. ANDY is compatible with several commonly usedDistributed Resource Management (DRM) systems, and it can be easilyextended to new DRMs. A distinctive feature of ANDY is the choice ofeither dedicated or fair-use operation: ANDY is almost as efficient assingle-purpose tools that… more
Date: December 21, 2005
Creator: Smith, Andrew; Chandonia, John-Marc & Brenner, Steven E.
Partner: UNT Libraries Government Documents Department
open access

Application of a General Computer Algorithm Based on the Group-Additivity Method for the Calculation of Two Molecular Descriptors at Both Ends of Dilution: Liquid Viscosity and Activity Coefficient in Water at Infinite Dilution

Description: This paper presents the application of a commonly used computer algorithm based on the group-additivity method for the calculation of the liquid viscosity coefficient at 293.15 K and the activity coefficient at infinite dilution in water at 298.15 K or organic molecules.
Date: December 21, 2017
Creator: Naef, Rudolf & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences
open access

Atomic processes in high-density plasmas

Description: This review covers dense atomic plasmas such as that produced in inertial confinement fusion. The target implosion physics along with the associated atomic physics, i.e., free electron collision phenomena, electron states I, electron states II, and nonequilibrium plasma states are described. (MOW)
Date: December 21, 1982
Creator: More, R.M.
Partner: UNT Libraries Government Documents Department
open access

Ba{sub 1{minus}x}Sr{sub x}TiO{sub 3} thin film sputter-growth processes and electrical property relationships for high frequency devices

Description: Precise control of Ba{sub 1{minus}x}Sr{sub x}Ti0{sub 3} (BST) film composition is critical for the production of high-quality BST thin films. Specifically, it is known that nonstoichiometry greatly affects the electrical properties of BST film capacitors. The authors are investigating the composition-microstructure-electrical property relationships of polycrystalline BST films produced by magnetron sputter-deposition using a single target with a Ba/Sr ratio of 50/50 and a (Ba+Sr)/Ti ratio of 1.… more
Date: December 21, 1999
Creator: Im, J.; Auciello, O.; Streiffer, S. K.; Baumann, P. K.; Eastman, J. A.; Kaufman, D. Y. et al.
Partner: UNT Libraries Government Documents Department
open access

A beamline matching application based on open source software

Description: An interactive Beamline Matching application has been developed using beamline and automatic differentiation class libraries. Various freely available components were used; in particular, the user interface is based on FLTK, a C++ toolkit distributed under the terms of the GNU Public License (GPL). The result is an application that compiles without modifications under both X-Windows and Win32 and offers the same look and feel under both operating environments. In this paper, we discuss some of … more
Date: December 21, 2000
Partner: UNT Libraries Government Documents Department
open access

Cascade effects on the polarization of He-like Fe 1s 2l - 1s2 X-ray line emission

Description: We calculate X-ray line polarization degrees for cases with axial symmetry using a collisional-radiative magnetic-sublevel atomic kinetics model and the properties of multipole radiation fields. This approach is well-suited for problems where the alignment is determined by the competition between many atomic processes. We benchmark this method against polarization measurements performed at the Livermore electron beam ion trap, and we study the 3-to-2 cascade effects on the polarization of 2-to-… more
Date: December 21, 2006
Creator: Hakel, P; Mancini, R; Harris, C; Neill, P; Beiersdorfer, P; Csanak, G et al.
Partner: UNT Libraries Government Documents Department
open access

Cascades from nu_E above 1020 eV

Description: At very high energies, the Landau-Pomeranchuk-Migdal effect reduces the cross sections for electron bremsstrahlung and photon e{sup +}e{sup -} pair production. The fractional electron energy loss and pair production cross sections drop as the energy increases. In contrast, the cross sections for photonuclear interactions grow with energy. In solids and liquids, at energies above 10{sup 20} eV, photonuclear reactions dominate, and showers that originate as photons or electrons quickly become had… more
Date: December 21, 2004
Creator: Klein, Spencer R.
Partner: UNT Libraries Government Documents Department
open access

Cavity BPM System Tests for the ILC Spectrometer

Description: The main physics program of the International Linear Collider (ILC) requires a measurement of the beam energy at the interaction point with an accuracy of 10{sup -4} or better. To achieve this goal a magnetic spectrometer using high resolution beam position monitors (BPMs) has been proposed. This paper reports on the cavity BPM system that was deployed to test this proposal. We demonstrate sub-micron resolution and micron level stability over 20 hours for a 1 m long BPM triplet. We find micron-… more
Date: December 21, 2007
Creator: Slater, M.
Partner: UNT Libraries Government Documents Department
open access

CHARACTERIZATION OF MODIFIED MONOSODIUM TITANATE - AN IMPROVED SORBENT FOR STRONTIUM AND ACTINIDE SEPARATIONS

Description: High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 134,137}Cs, {sup 90}Sr, and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. An inorganic sorbent, monosodium titanate (MST), is currently used to remove {sup 90}Sr and alpha-emitting radionuclides, while a caustic-side solvent extraction process is used for removing {sup 134,137}Cs. A new peroxotitanate material, mo… more
Date: December 21, 2010
Creator: Hobbs, D.; Taylor-Pashow, K. & Missimer, D.
Partner: UNT Libraries Government Documents Department
open access

Charm Spectroscopy at BaBar

Description: We present a mini-review on charm spectroscopy at the BABAR experiment. We first report on the c{bar s} meson spectrum, and present precise measurements of the D{sub s1}(2536) meson as well as the properties of the many new states discovered since 2003 (D*{sub s0}(2317), D{sub s1}(2460), D*{sub sJ}(2860), and D{sub sJ}(2700) mesons). We then discuss about charmed baryons observed recently in the BABAR experiment: {Omega}{sub c}{sup 0} and {Omega}*{sub c}{sup 0} css baryons, {Lambda}{sub c}(2940… more
Date: December 21, 2007
Creator: Poireau, Vincent
Partner: UNT Libraries Government Documents Department
open access

Chemical Solution Processing of Strontium Bismuth Tantalate Films

Description: We describe Chemical Solution Deposition (CSD) processes by which Strontium Bismuth Tantalate (SBT) thin films can be prepared at temperatures as low as 550 C. In this paper, we will present strategies used to optimize the properties of the films including solution chemistry, film composition, the nature of the substrate (or bottom electrode) used, and the thermal processing cycle. Under suitable conditions, {approximately} 1700 {angstrom} films can be prepared which have a large switchable pol… more
Date: December 21, 1998
Creator: Boyle, T.J. & Lakeman, C.D.E.
Partner: UNT Libraries Government Documents Department
open access

Coarse-Grained Molecular Dynamics and Multiscale Modeling of NEMS Resonators

Description: We review concurrent multiscale simulations of dynamic and temperature-dependent processes found in nanomechanical systems coupled to larger scale surroundings. We focus on the behavior of sub-micron Micro-Electro-Mechanical Systems (MEMS), especially microresonators. These systems are often called NEMS, for Nano-Electro-Mechanical Systems. The coupling of length scales methodology we have developed for MEMS employs an atomistic description of small but key regions of the system, consisting of … more
Date: December 21, 2001
Creator: Rudd, R E
Partner: UNT Libraries Government Documents Department
open access

Coarse-Grained Molecular Dynamics: Dissipation Due to Internal Modes

Description: We describe progress on the issue of pathological elastic wave reflection in atomistic and multiscale simulation. First we briefly review Coarse-Grained Molecular Dynamics (CGMD). Originally CGMD was formulated as a Hamiltonian system in which energy is conserved. This formulation is useful for many applications, but recently CGMD has been extended to include generalized Langevin forces. Here we describe how Langevin dynamics arise naturally in CGMD, and we examine the implication for elastic w… more
Date: December 21, 2001
Creator: Rudd, R E
Partner: UNT Libraries Government Documents Department
open access

Collectivity of the ''Three-Phonon'' Region in {sup 100}Ru

Description: We have studied the quadrupole degree of freedom in a typical vibrational nucleus, {sup 100}Ru. From inelastic neutron scattering at the Van de Graaff accelerator of the University of Kentucky, lifetimes of states in {sup 100}Ru were determined. Absolute transition rates or limits thereon were extracted and compared to the theoretical description of this nucleus.
Date: December 21, 1999
Creator: Genilloud, L.; Brown, T.B.; Corminboeuf, G & Garrett, P.
Partner: UNT Libraries Government Documents Department
open access

Comparison of Four Parallel Algorithms For Domain Decomposed Implicit Monte Carlo

Description: We consider two existing asynchronous parallel algorithms for Implicit Monte Carlo (IMC) thermal radiation transport on spatially decomposed meshes. The two algorithms are from the production codes KULL from Lawrence Livermore National Laboratory and Milagro from Los Alamos National Laboratory. Both algorithms were considered and analyzed in an implementation of the KULL IMC package in ALEGRA, a Sandia National Laboratory high energy density physics code. Improvements were made to both algorith… more
Date: December 21, 2004
Creator: Brunner, T A; Urbatsch, T J; Evans, T M & Gentile, N A
Partner: UNT Libraries Government Documents Department
open access

Comparison of Four Parallel Algorithms For Domain Decomposed Implicit Monte Carlo

Description: Four different algorithms for domain decomposed Monte Carlo are outlined, and the performance of each is measured. These algorithms are implemented in the KULL IMC package [4] running inside of ALEGRA [1]. This package implements the Implicit Monte Carlo (IMC) scheme for thermal radiation transport of Fleck and Cummings [3].
Date: December 21, 2004
Creator: Brunner, T; Urbatsch, T; Evans, T & Gentile, N
Partner: UNT Libraries Government Documents Department
open access

Comparisons of hydrodynamic beam models with kinetic treatments. Revision 1

Description: Hydrodynamic models have been derived by Mark and Yu and by others to described energetic self-pinch beams, such as those used in ion-beam fusion. The closure of the Mark-Yu model is obtained with adiabatic assumptions mathematically analogous to those of Chew, Goldberger, and Low for MHD. The other models treated here use an ideal gas closure and a closure by Newcomb based on an expansion in V/sub th//V/sub z/. Features of these hydrodynamic beam models are compared with a kinetic treatment.
Date: December 21, 1983
Creator: Boyd, J. K.; Mark, J. W.; Sharp, W. M. & Yu, S. S.
Partner: UNT Libraries Government Documents Department
open access

Conversion and optimization of the parameters from an extended form of the ion-interaction model for Ca(NO3)2(aq) and NaNO3(aq) to those of the standard Pitzer model, and an assessment of the accuracy of the parameter temperature representations

Description: The electrolytes Ca(NO{sub 3}){sub 2}(aq) and NaNO{sub 3}(aq) are both extremely soluble but differ in several important respects. Ca(NO{sub 3}){sub 2}(aq) has complex behavior at low ionic strengths and forms several thermodynamically stable and metastable solid phases, whereas NaNO{sub 3}(aq) forms only an anhydrous solid phase. The thermodynamic properties of both have previously been modeled using extended Pitzer ion-interaction models that include higher-order virial terms, in addition to … more
Date: December 21, 2004
Creator: Wijesinghe, A M & Rard, J A
Partner: UNT Libraries Government Documents Department
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