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Combustible radioactive waste treatment by incineration and chemical digestion (open access)

Combustible radioactive waste treatment by incineration and chemical digestion

A review is given of present and planned combustible radioactive waste treatment systems in the US. Advantages and disadvantages of various systems are considered. Design waste streams are discussed in relation to waste composition, radioactive contaminants by amount and type, and special operating problems caused by the waste.
Date: May 28, 1980
Creator: Stretz, L. A.; Crippen, M. D. & Allen, C. R.
System: The UNT Digital Library
Broadband diffractive lens (open access)

Broadband diffractive lens

Significant progress has been made toward solving the century-old problem of chromatic aberrations in diffractive optics. Our approach exploits modern materials and microfabrication technology and is very different from the purely diffractive strategy,'' which is commonly employed and which results in multiple diffractive elements separated by a finite distance. We have developed a Fresnel zone plate lens comprised of a serial stack of patterned minus-filters which allows broadband radiation to be focused (or imaged) without longitudinal or transverse chromatic aberrations. 7 refs., 4 figs.
Date: May 28, 1991
Creator: Ceglio, N. M.; Hawryluk, A. M.; London, R. A.; Seppala, L. G. (Lawrence Livermore National Lab., CA (USA)) & Gaines, D. P. (Brigham Young Univ., Provo, UT (USA))
System: The UNT Digital Library
Data acquisition system for the HHIRF spin spectrometer (open access)

Data acquisition system for the HHIRF spin spectrometer

The Spin Spectrometer at the Holifield Heavy Ion Research Facility (HHIRF) is a multidetector ..gamma..-ray spectrometer consisting of 72 separate NaI detector elements closely packed in a 4..pi.. geometry. The basic apparatus was constructed at Washington University and has been installed and implemented at the HHIRF at Oak Ridge National Laboratory. The spectrometer was designed especially for the investigation of the mechanisms of heavy-ion induced nuclear reactions and of the structure of nuclei with high angular momentum. The data acquisition system is described. (WHK)
Date: May 28, 1981
Creator: Hensley, D.C.
System: The UNT Digital Library
Studies of the Formation of Field Reversed Plasma by a Magnetized Co-Axial Plasma Gun (open access)

Studies of the Formation of Field Reversed Plasma by a Magnetized Co-Axial Plasma Gun

The gun injects axially into a drift tank followed by a magnetic mirror. For the experiments reported here, only the guide coils outside the vacuum vessel and solenoids on the plasma gun electrodes were used; the mirror coil was not energized. A stainless steel flux conserver is placed in the mirror throat to prevent the plasma from contacting the nonconducting vacuum wall in the region of the mirror. An axis encircling array of magnetic loop probes includes four diamagnetic loops and a loop which measures the azimuthally averaged outward pointing radial component of magnetic field. These loop probes are stainless steel jacketed and form a flux conserving boundary (at a radius = 30 cm) for plasma emitted from the gun. A five tip probe that can be positioned anywhere along the axis of the experiment is used to measure internal components of magnetic field.
Date: May 28, 1980
Creator: Turner, W. C.; Granneman, E. H. A.; Hartman, C. W.; Prono, D. S.; Taska, J. & Smith, A. C., Jr.
System: The UNT Digital Library
Movable Genetic Elements: Detection of Changes in Maize DNA at the Shrunken Locus Due to the Intervention of Ds Elements (open access)

Movable Genetic Elements: Detection of Changes in Maize DNA at the Shrunken Locus Due to the Intervention of Ds Elements

This report describes our initial attempts at the molecular characterization of a maize controlling element. We have prepared a cDNA probe and used it to detect changes at a locus where Ds elements are found. Evidence of their presence are indicated by changes in the restriction patterns, but there is as yet no information on the physical nature of the controlling elements nor on the kinds of rearrangements they cause.
Date: May 28, 1980
Creator: Burr, B. & Burr, F.A.
System: The UNT Digital Library
Performance of two-phase nozzles for total flow geothermal impulse turbines (open access)

Performance of two-phase nozzles for total flow geothermal impulse turbines

None
Date: May 28, 1975
Creator: Alger, T.W.
System: The UNT Digital Library
Model for H/sup -/, D/sup -/ production by hydrogen backscattering from alkali and alkali/transition-metal surfaces (open access)

Model for H/sup -/, D/sup -/ production by hydrogen backscattering from alkali and alkali/transition-metal surfaces

A model for H/sup -/, D/sup -/ production by energetic particles reflecting from metal surfaces is discussed. The model employs the energy and angular distribution data derived from the Marlowe code. The model is applied to particles incident normally upon Cs, Ni, and Cs/Ni surfaces.
Date: May 28, 1980
Creator: Hiskes, J.R. & Schneider, P.J.
System: The UNT Digital Library
Mapping the geometry of the F4 group (open access)

Mapping the geometry of the F4 group

In this paper, we present a construction of the compact form of the exceptional Lie group F4 by exponentiating the corresponding Lie algebra f4. We realize F4 as the automorphisms group of the exceptional Jordan algebra, whose elements are 3 x 3 Hermitian matrices with octonionic entries. We use a parametrization which generalizes the Euler angles for SU(2) and is based on the fibration of F4 via a Spin(9) subgroup as a fiber. This technique allows us to determine an explicit expression for the Haar invariant measure on the F4 group manifold. Apart from shedding light on the structure of F4 and its coset manifold OP2 = F4/Spin(9), the octonionic projective plane, these results are a prerequisite for the study of E6, of which F4 is a (maximal) subgroup.
Date: May 28, 2007
Creator: Bernardoni, Fabio; Cacciatori, Sergio L; Scotti, Antonio & Cerchiai, Bianca L.
System: The UNT Digital Library
Photoemission Study of Cs-NF3 Activated GaAs(100) Negative Electron Affinity Photocathodes (open access)

Photoemission Study of Cs-NF3 Activated GaAs(100) Negative Electron Affinity Photocathodes

GaAs based negative electron affinity photocathodes activated with Cs and NF{sub 3} are used as polarized electron sources for linear accelerators. It is generally believed that the activation layer consists of CsF. The activation layers of Cs-NF{sub 3} on GaAs photocathodes are herein investigated using synchrotron radiation photoelectron spectroscopy (SR-PES). F1s, N1s and other core levels are recorded at photon energies ranging from 70eV to 820eV. Surprisingly, a significant amount of nitrogen is observed in the activation layers. Two distinct species of nitrogen are observed, one of which decreases along with the Fluorine signal as the yield of the photocathode decays with time.
Date: May 28, 2008
Creator: Liu, Z.; Sun, Y.; Peterson, S. & Pianetta, P.
System: The UNT Digital Library
SUSY at the ILC and Solving the LHC Inverse Problem (open access)

SUSY at the ILC and Solving the LHC Inverse Problem

Recently a large scale study of points in the MSSM parameter space which are problematic at the Large Hadron Collider (LHC) has been performed. This work was carried out in part to determine whether the proposed International Linear Collider (ILC) could be used to solve the LHC inverse problem. The results suggest that while the ILC will be a valuable tool, an energy upgrade may be crucial to its success, and that, in general, precision studies of the MSSM are more difficult at the ILC than has generally been believed.
Date: May 28, 2008
Creator: Gainer, James S.
System: The UNT Digital Library
Factorization and resummation for collinear poles in QCD amplitudes (open access)

Factorization and resummation for collinear poles in QCD amplitudes

We study the origin of subleading soft and collinear poles of form factors and amplitudes in dimensionally-regulated massless gauge theories. In the case of form factors of fundamental fields, these poles originate from a single function of the coupling, denoted G({alpha}{sub s}), depending on both the spin and gauge quantum numbers of the field. We relate G({alpha}{sub s}) to gauge-theory matrix elements involving the gluon field strength. We then show that G({alpha}{sub s}) is the sum of three terms: a universal eikonal anomalous dimension, a universal non-eikonal contribution, given by the coefficient B{sub {delta}}({alpha}{sub s}) of {delta}(1-z) in the collinear evolution kernel, and a process-dependent short-distance coefficient function, which does not contribute to infrared poles. Using general results on the factorization of soft and collinear singularities in fixed-angle massless gauge theory amplitudes, we conclude that all such singularities are captured by the eikonal approximation, supplemented only by the knowledge of B{sub {delta}}({alpha}{sub s}). We explore the consequences of our results for conformal gauge theories, where in particular we find a simple exact relation between the form factor and the cusp anomalous dimension.
Date: May 28, 2008
Creator: Dixon, Lance J.; Magnea, Lorenzo & Sterman, George
System: The UNT Digital Library
Probing the Geometry of Warped String Compactifications at the LHC (open access)

Probing the Geometry of Warped String Compactifications at the LHC

Warped string compactifications, characterized by the nonsingular behavior of the metric in the infrared (IR), feature departures from the usual anti?de Sitter warped extra dimensions. We study the implications of the smooth IR cutoff for Randall-Sundrum- (RS-)type models. We find that the phenomenology of the Kaluza-Klein gravitons (including their masses and couplings) depends sensitively on the precise shape of the warp factor in the IR. In particular, we analyze the warped deformed conifold, find that the spectrum differs significantly from that of RS, and present a simple prescription (a mass-gap ansatz) that can be used to study the phenomenology of IR modifications to 5D warped extra dimensions.
Date: May 28, 2007
Creator: Walker, Devin; Shiu, Gary; Underwood, Bret; Zurek, Kathryn M. & Walker, Devin G. E.
System: The UNT Digital Library
Gas Mixing Analysis in a Large-Scaled Saltstone Facility (open access)

Gas Mixing Analysis in a Large-Scaled Saltstone Facility

Computational fluid dynamics (CFD) methods have been used to estimate the flow patterns mainly driven by temperature gradients inside vapor space in a large-scaled Saltstone vault facility at Savannah River site (SRS). The purpose of this work is to examine the gas motions inside the vapor space under the current vault configurations by taking a three-dimensional transient momentum-energy coupled approach for the vapor space domain of the vault. The modeling calculations were based on prototypic vault geometry and expected normal operating conditions as defined by Waste Solidification Engineering. The modeling analysis was focused on the air flow patterns near the ventilated corner zones of the vapor space inside the Saltstone vault. The turbulence behavior and natural convection mechanism used in the present model were benchmarked against the literature information and theoretical results. The verified model was applied to the Saltstone vault geometry for the transient assessment of the air flow patterns inside the vapor space of the vault region using the potential operating conditions. The baseline model considered two cases for the estimations of the flow patterns within the vapor space. One is the reference nominal case. The other is for the negative temperature gradient between the roof inner and …
Date: May 28, 2008
Creator: Lee, S.
System: The UNT Digital Library
Weak Emission-Line Quasars in the Context of a Modified Baldwin Effect (open access)

Weak Emission-Line Quasars in the Context of a Modified Baldwin Effect

This article tests whether the modified Baldwin effect remains strong across the wides possible of ranges of redshift and luminosity.
Date: May 28, 2015
Creator: Shemmer, Ohad
System: The UNT Digital Library
Methods for fabricating arrays of holes using interference lithography (open access)

Methods for fabricating arrays of holes using interference lithography

Optical interference lithography offers a robust patterning technology capable of achieving high spatial resolution over extremely large field sizes ( {approx}1 m ). Here, we compare two different approaches for fabricating arrays of holes using interferometric techniques. We show that by applying an image reversal process to standard two-beam interference lithography, arrays of high aspect ratio holes can be generated. This process scales to submicron periods and allows holes as small as 0.1 micron to be patterned. Next, we present an analysis of the multiple-beam approach for patterning holes. We demonstrate that while the formation of higher contrast intensity patterns is possible by interfering four or more beams, the shape and modulation depth of such patterns are inherently sensitive to relative phase variations.
Date: May 28, 1997
Creator: Fernandez, A.; Decker, J. Y.; Herman, S. M.; Phillion, D. W.; Sweeney, D. W. & Perry, M. D.
System: The UNT Digital Library
Entry State Distributions of Discrete Yrast Transitions in Heavy Ion Induced Fusion Reactions (open access)

Entry State Distributions of Discrete Yrast Transitions in Heavy Ion Induced Fusion Reactions

Gamma rays emitted during yrast transitions from compound nuclei are detected with a 4..pi.. multielement gamma ray detector system. Both total pulse height (H) and coincidence fold data (k) are obtained for each event. Results presented include entry state distribution states, k and H projections for some of these distributions, and k and H as a function of spin of the yrast transition. 5 figs. (DWL)
Date: May 28, 1985
Creator: Lee, I. Y.; Baktash, C.; Beene, J. R.; Fewell, M. P.; Halbert, M. L.; Johnson, N. R. et al.
System: The UNT Digital Library
Chemicals and excess materials disposition during facility deactivation as a means of pollution prevention (open access)

Chemicals and excess materials disposition during facility deactivation as a means of pollution prevention

This paper presents several innovative and common sense approaches to pollution prevention that have been employed during facility deactivation at the Hanford Site in South Central Washington. It also presents several pollution prevention principles applicable to other projects. Innovative pollution prevention ideas employed at the Hanford site during facility deactivation included: (1) Recycling more than 185,000 gallons of radioactively contaminated nitric acid by sending it to an operating nuclear fuels reprocessing facility in England; (2) Recycling millions of pounds of chemicals and excess materials to other industries for reuse; (3) Evaporating flush water at a low rate and discharging it into the facility exhaust air stream to avoid discharging thousands of gallons of liquid to the soil column; and (4) Decontaminating and disposing of thousands of gallons of radioactively contaminated organic solvent waste to a RCRA licensed, power-producing, commercial incinerator. Common sense pollution prevention ideas that were employed include recycling office furniture, recycling paper from office files, and redeploying tools and miscellaneous process equipment. Additional pollution prevention occurred as the facility liquid and gaseous discharge streams were deactivated. From the facilities deactivation experiences at Hanford and the ensuing efforts to disposition excess chemicals and materials, several key pollution prevention principles …
Date: May 28, 1998
Creator: Godfrey, S. D.
System: The UNT Digital Library
Laser beam trapping and propagation in cylindrical plasma columns (open access)

Laser beam trapping and propagation in cylindrical plasma columns

An analysis of the scheme to heat magnetically confined plasma columns to kilovolt temperatures with a laser beam requires consideration of two propagation problems. The first question to be answered is whether stable beam trapping is possible. Since the laser beam creates its own density profile by heating the plasma, the propagation of the beam becomes a nonlinear phenomenon, but not necessarily a stable one. In addition, the electron density at a given time depends on the preceding history of both the medium and the laser pulse. A self-consistent time dependent treatment of the beam propagation and the medium hydrodynamics is consequently required to predict the behavior of the laser beam. Such calculations have been carried out and indicate that propagation of a laser beam in an initially uniform plasma can form a stable filament which alternately focuses and defocuses. An additional question that is discussed is whether diffractive losses associated with long propagation paths are significant.
Date: May 28, 1976
Creator: Feit, M. D. & Fleck, J. A., Jr.
System: The UNT Digital Library
Measurement of the D*(2010)+ Natural Line Width and the D*(2010)+ - D0 Mass Difference (open access)

Measurement of the D*(2010)+ Natural Line Width and the D*(2010)+ - D0 Mass Difference

None
Date: May 28, 2013
Creator: unknown
System: The UNT Digital Library
Measurement of the Inclusive and Dijet Cross-sections of b-jets in pp Collisions at sqrt(s) = 7 TeV with the ATLAS Detector (open access)
Demonstration of Surface Electron Rejection with Interleaved Germanium Detectors for Dark Matter Search (open access)

Demonstration of Surface Electron Rejection with Interleaved Germanium Detectors for Dark Matter Search

Measures charge and athermal phonons from each particle interaction,which provides excellent discrimination between electron recoils and nuclear recoils.
Date: May 28, 2013
Creator: Agnese, R.; Anderson, A. J.; Balakishiyeva, D.; Thakur, R.; Bauer, D. A.; Borgland, A. et al.
System: The UNT Digital Library
Fermi LAT Observations of Cosmic-Ray Electrons From 7 GeV to 1 TeV (open access)

Fermi LAT Observations of Cosmic-Ray Electrons From 7 GeV to 1 TeV

None
Date: May 28, 2013
Creator: Ackermann, M.; Ajello, M.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G. et al.
System: The UNT Digital Library
PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN (open access)

PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN

Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project-Hanford Tank Waste Treatment & Immobilization Plant (WTP) Project. The RF resin hydraulic cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Sixteen of these cycles were completed in the 24-inch IX Column (1/2 scale column). Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 3 times better than the design requirements of the WTP full-scale IX system. The RF resin bed showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible …
Date: May 28, 2009
Creator: Adamson, D.
System: The UNT Digital Library