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Burning nuclear wastes in fusion reactors

Description: We have studied actinide burn-up in ICF reactor pellets; i.e., 14 MeV neutron fission of the very long-lived actinides that pose storage problems. A major advantage of pellet fuel region burn-up is safety: only milligrams of highly toxic and active material need to be present in the fusion chamber, whereas blanket burn-up requires the continued presence of tons of actinides in a small volume. The actinide data tables required for Monte Carlo calculations of the burn-up of /sup 241/Am and /sup 2… more
Date: February 20, 1980
Creator: Meldner, H.W. & Howard, W.M.
Partner: UNT Libraries Government Documents Department
open access

GeV electron beams from cm-scale channel guided laser wakefieldaccelerator

Description: Laser-wakefield accelerators (LWFA) can produce electricfields of order 10-100 GV/m suitable for acceleration of electrons torelativistic energies. The wakefields are excited by a relativisticallyintense laser pulse propagating through a plasma and have a phasevelocity determined by the group velocity of the light pulse. Twoimportant effects that can limit the acceleration distanceand hence thenet energy gain obtained by an electron are diffraction of the drivelaser pulse and particle-wake deph… more
Date: February 20, 2007
Creator: Nakamura, K.; Nagler, B.; Toth, Cs.; Geddes, C. G. R.; Schroeder, C.; Esarey, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Estimating Filtering Errors Using the Peano Kernel Theorem

Description: The Peano Kernel Theorem is introduced and a frequency domain derivation is given. It is demonstrated that the application of this theorem yields simple and accurate formulas for estimating the error introduced into a signal by filtering it to reduce noise.
Date: February 20, 2009
Creator: Blair, Jerome
Partner: UNT Libraries Government Documents Department
open access

Primordial Compositions of Refractory Inclusions

Description: Bulk chemical and oxygen, magnesium and silicon isotopic compositions were measured for each of 17 Types A and B refractory inclusions from CV3 chondrites. After bulk chemical compositions were corrected for non-representative sampling in the laboratory, the Mg and Si isotopic compositions of each inclusion were used to calculate its original chemical composition assuming that the heavy-isotope enrichments of these elements are due to Rayleigh fractionation that accompanied their evaporation fr… more
Date: February 20, 2008
Creator: Grossman, L.; Simon, S. B.; Rai, V. K.; Thiemens, M. H.; Hutcheon, I. D.; Williams, R. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Simulation Strategies for Shock-Turbulence Interactions

Description: The computational challenge of predicting shock-turbulence interactions stems from the fundamentally different physics at play. Shock waves are microscopically thin regions wherein flow properties change rapidly over a distance roughly equal to the molecular mean free path; hence, they are essentially strong discontinuities in the flow field. Turbulence, on the other hand, is a chaotic phenomenon with broadband spatial and temporal scales of motion. Most shock-capturing methods rely on strong n… more
Date: February 20, 2008
Creator: Cook, A; Larsson, J; Cabot, W & Lele, S K
Partner: UNT Libraries Government Documents Department
open access

Applied Focused Ion Beam Techniques for Sample Preparation of Astromaterials for Integrated Nano-Analysis

Description: Sample preparation is always a critical step in study of micrometer sized astromaterials available for study in the laboratory, whether their subsequent analysis is by electron microscopy or secondary ion mass spectrometry. A focused beam of gallium ions has been used to prepare electron transparent sections from an interplanetary dust particle, as part of an integrated analysis protocol to maximize the mineralogical, elemental, isotopic and spectroscopic information extracted from one individu… more
Date: February 20, 2007
Creator: Graham, G A; Teslich, N E; Kearsley, A T; Stadermann, F J; Stroud, R M; Dai, Z R et al.
Partner: UNT Libraries Government Documents Department
open access

Modeling of Laser-Induced Metal Combustion

Description: Experiments involving the interaction of a high-power laser beam with metal targets demonstrate that combustion plays an important role. This process depends on reactions within an oxide layer, together with oxygenation and removal of this layer by the wind. We present an analytical model of laser-induced combustion. The model predicts the threshold for initiation of combustion, the growth of the combustion layer with time, and the threshold for self-supported combustion. Solutions are compared… more
Date: February 20, 2008
Creator: Boley, C D & Rubenchik, A M
Partner: UNT Libraries Government Documents Department
open access

A METHOD FOR STATIC-FIELD COMPRESSION IN AN ELECTRON-RING ACCELERATOR

Description: A review of methods for static-field compression of an electron ring is shown to suggest advantages for a method in which there is no axial acceleration or deceleration of the ring. In the method proposed here the static magnetic field itself is o such a character that the electrons are neither focused nor defocused in the axial direction. The integrity and movement of the ring through the compressor is controlled by a small traveling magnetic well. The feasibility of creating such a traveling … more
Date: February 20, 1969
Creator: Laslett, L.Jackson & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
open access

Platinum particles in the Nd:doped disks of phosphate glass in the Nova laser

Description: The disks of Nd:doped phosphate glass in the amplifiers of the Nova laser contain platinum particles with sizes ranging from <5 ..mu..m (detection limit) to about 100 ..mu..m. The particle density varies from about 0.01 to 1.0 cm/sup -3/. These particles cause fractures when irradiated at fluences >2.5 J/cm/sup 2/ delivered in 1-ns, 1054-nm pulses. Under repeated irradiation at 5 to 7 J/cm/sup 2/, damage from small (<5 ..mu..m) particles asymptotically approaches a limiting size, but damage sur… more
Date: February 20, 1986
Creator: Milam, D.; Hatcher, C. W. & Campbell, J. H.
Partner: UNT Libraries Government Documents Department
open access

The status of fuel cell technology

Description: This brief status report provides an introduction to what fuel cells are, why they are important, what uses have been made of them to date, the goals and timetables of current programs, and who the players are in this vital technology. Copies of most of the slides presented and additional diagrams are appended to this paper. Further details can be obtained from the comprehensive texts cited in the bibliography. 11 refs., 44 figs.
Date: February 20, 1991
Creator: O'Sullivan, J.B.
Partner: UNT Libraries Government Documents Department
open access

Search for Neutrino Oscillations at the Brookhaven AGS

Description: We report on a search for neutrino oscillations of the type nu/sub ..mu../ ..-->.. nu/sub e/ in a detector located an effective distance of 96m from the neutrino source in the wide band neutrino beam at the Brookhaven AGS. No excess of electron events was observed. The resulting upper limit on the strength of the mixing between nu/sub ..mu../ and nu/sub e/ in the case of large mass difference ..delta..m/sup 2/ = absolute value m/sub 1//sup 2/ - m/sub 2//sup 2/ between the neutrino mass eigensta… more
Date: February 20, 1985
Creator: Ahrens, L. A.; Aronson, S. H.; Connolly, P. L.; Gibbard, B. G.; Murtagh, M. J.; Murtagh, S. J. et al.
Partner: UNT Libraries Government Documents Department
open access

Practical, cost-effective method for real-time surveillance of widely-separated remote sites. [System based on FM CATV concept]

Description: Effective intrusion protection for uninhabited sites scattered widely throughout a large geographic area can be a difficult and expensive proposition. When the sites are important enough to require continuous surveillance, the problem is even worse. Roving patrols are not effective, and conventional alarms don't provide enough information to allow a meaningful response. Television systems have possibilities but also disadvantages: the usual system is both costly and inflexible. This paper descr… more
Date: February 20, 1979
Creator: Braley, R.E.; Olson, A.W. & Rufer, R.P.
Partner: UNT Libraries Government Documents Department
open access

High-resolution crystal spectrometer for the 10-60 (angstrom) EUV region

Description: A vacuum crystal spectrometer with nominal resolving power approaching 1000 is described for measuring emission lines with wavelength in the extreme ultraviolet region up to 60 Angstroms. The instrument utilizes a flat octadecyl hydrogen maleate (OHM) crystal and a thin-window 1-D position-sensitive gas proportional detector. This detector employs a 1 {micro}m-thick 100 x8 mm{sup 2} aluminized polyimide window and operates at one atmosphere pressure. The spectrometer has been implemented on the… more
Date: February 20, 2004
Creator: Beiersdorfer, P; Brown, G V; Goddard, R & Wargelin, B J
Partner: UNT Libraries Government Documents Department
open access

Importance of Supernovae at z&lt;0.1 for Probing Dark Energy

Description: Supernova experiments to characterize dark energy require a well designed low redshift program; we consider this for both ongoing/near term (e.g. Supernova Legacy Survey) and comprehensive future (e.g., SNAP) experiments. The derived criteria are: a supernova sample centered near z=0.05 comprising 150-500 (in the former case) and 300-900 (in the latter case) well measured supernovae. Low redshift Type Ia supernovae play two important roles for cosmological use of the supernova distance-redshift… more
Date: February 20, 2007
Creator: Miller, Jeanne M & Linder, E.V.
Partner: UNT Libraries Government Documents Department
open access

MECHANICAL ALLOYING AND THERMAL TREATMENT FOR PRODUCTION OF ZIRCONIUM IRON HYDROGEN ISOTOPE GETTERS

Description: The objective of this task was to demonstrate that metal hydrides could be produced by mechanical alloying in the quantities needed to support production-scale hydrogen isotope separations. Three starting compositions (ratios of elemental Zr and Fe powders) were selected and attritor milled under argon for times of 8 to 60 hours. In general, milling times of at least 24 hours were required to form the desired Zr{sub 2}Fe and Zr{sub 3}Fe phases, although a considerable amount of unalloyed Zr and… more
Date: February 20, 2008
Creator: Fox, K.
Partner: UNT Libraries Government Documents Department
open access

Water-Soluble 2-Hydroxyisophthalamides for Sensitization of Lanthanide Luminescence

Description: A series of octadentate ligands featuring the 2-hydroxyisophthalamide (IAM) antenna chromophore (to sensitize Tb(III) and Eu(III) luminescence) has been prepared and characterized. The length of the alkyl amine scaffold that links the four IAM moieties has been varied in order to investigate the effect of the ligand backbone on the stability and photophysical properties of the Ln(III) complexes. The amine backbones utilized in this study are N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-ethane-… more
Date: February 20, 2008
Creator: Samuel, Amanda P. S.; Moore, Evan G.; Melchior, Marco; Xu, Jide & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department
open access

THE INTEGRATION OF THE 241-Z BUILDING DECONTAMINATION & DECOMMISSIONING (D&D) UNDER COMPREHENSIVE ENVIRONMENTAL RESPONSE COMPENSATION & LIABILITY ACT (CERCLA) WITH RESOURCE CONSERVATION & RECOVERY ACT (RCRA) CLOSURE AT THE PLUTONIUM FINISHING PLANT (PFP)

Description: The 241-Z treatment and storage tanks, a hazardous waste Treatment, Storage and Disposal (TSD) unit permitted pursuant to the ''Resource Conservation and Recovery Act of 1976'' (RCRA) and Washington State ''Hazardous Waste Management Act, RCW 70.105'', have been deactivated and are being actively decommissioned. The 241-Z TSD unit managed non-listed radioactive contaminated waste water, containing trace RCRA characteristic constituents. The 241-Z TSD unit consists of below grade tanks (D-4, D-5… more
Date: February 20, 2007
Creator: HOPKINS, A.M.
Partner: UNT Libraries Government Documents Department
open access

Charting the Course for Elementary Particle Physics

Description: ''It was the best of times; it was the worst of times'' is the way Dickens begins the Tale of Two Cities. The line is appropriate to our time in particle physics. It is the best of times because we are in the midst of a revolution in understanding, the third to occur during my career. It is the worst of times because accelerator facilities are shutting down before new ones are opening, restricting the opportunity for experiments, and because of great uncertainty about future funding. My task to… more
Date: February 20, 2007
Creator: Richter, Burton
Partner: UNT Libraries Government Documents Department
open access

Spatial Analysis of Emissions Sources for HCCI Combustion at Low Loads Using a Multi-Zone Model

Description: We have conducted a detailed numerical analysis of HCCI engine operation at low loads to investigate the sources of HC and CO emissions and the associated combustion inefficiencies. Engine performance and emissions are evaluated as fueling is reduced from typical HCCI conditions, with an equivalence ratio f = 0.26 to very low loads (f = 0.04). Calculations are conducted using a segregated multi-zone methodology and a detailed chemical kinetic mechanism for iso-octane with 859 chemical species. … more
Date: February 20, 2004
Creator: Aceves, S. M.; Flowers, D. L.; Espinosa-Loza, F.; Martinez-Frias, J.; Dec, J. E.; Sjoberg, M. et al.
Partner: UNT Libraries Government Documents Department
open access

The differentiation history of the terrestrial planets as recorded on the moon

Description: The outline for this report is: (1) Factors Leading to Lunar Magma Ocean Model for Planetary Differentiation (2) Rationale for Magma Oceans on Other Planets Means for early efficient differentiation (Works on Moon why not here?) (3) Some Inconsistencies between the Lunar Magma Ocean Model and Observations. The conclusions are: (1) Differentiation via solidification of a magma ocean is derived from geologic observations of the Moon (2) Although geologic observations on other bodies are often con… more
Date: February 20, 2007
Creator: Borg, L
Partner: UNT Libraries Government Documents Department
open access

CRATES: An All-Sky Survey of Flat-Spectrum Radio Sources

Description: We have assembled an 8.4 GHz survey of bright, flat-spectrum ({alpha} &gt; -0.5) radio sources with nearly uniform extragalactic (|b| &gt; 10{sup o}) coverage for sources brighter than S{sub 4.8 GHz} = 65 mJy. The catalog is assembled from existing observations (especially CLASS and the Wright et al. PMN-CA survey), augmented by reprocessing of archival VLA and ATCA data and by new observations to fill in coverage gaps. We refer to this program as CRATES, the Combined Radio All-sky Targeted Eig… more
Date: February 20, 2007
Creator: Healey, Stephen E.; Romani, Roger W.; Taylor, Gregory B.; Sadler, Elaine M.; Ricci, Roberto; Murphy, Tara et al.
Partner: UNT Libraries Government Documents Department
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