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Reduction of pertechnetate by acetohydroxamic acid: Formation of [TcNO(AHA)2(H2O)]+ and implications for the UREX process.

Description: Reductive nitrosylation and complexation of ammonium pertechnetate by acetohydroxamic acid has been achieved in aqueous nitric and perchloric acid solutions. The kinetics of the reaction depend on the relative concentrations of the reaction components and are accelerated at higher temperatures. The reaction does not occur unless conditions are acidic. Analysis of the x-ray absorption fine structure spectroscopic data is consistent with a pseudo-octahedral geometry with the linear Tc-N-O bond ty… more
Date: February 26, 2008
Creator: 1Harry Reid Center for Environmental Studies, Nuclear Science and Technology Division, University of Nevada, Las Vegas, Las Vegas, NV, 89154-4006; Gong, Cynthia-May S; Poineau, Frederic; Lukens, Wayne W & Czerwinski, Kenneth R.
Partner: UNT Libraries Government Documents Department
open access

Frequency Doubling Broadband Light in Multiple Crystals

Description: The authors compare frequency doubling of broadband light in a single nonlinear crystal with doubling in five crystals with intercrystal temporal walk off compensation, and with doubling in five crystals adjusted for offset phase matching frequencies. Using a plane-wave, dispersive numerical model of frequency doubling they study the bandwidth of the second harmonic and the conversion efficiency as functions of crystal length and fundamental irradiance. For low irradiance the offset phase match… more
Date: July 26, 2000
Creator: ALFORD,WILLIAM J. & SMITH,ARLEE V.
Partner: UNT Libraries Government Documents Department
open access

FULL SCALE TESTING TECHNOLOGY MATURATION OF A THIN FILM EVAPORATOR FOR HIGH-LEVEL LIQUID WASTE MANAGEMENT AT HANFORD - 12125

Description: Simulant testing of a full-scale thin-film evaporator system was conducted in 2011 for technology development at the Hanford tank farms. Test results met objectives of water removal rate, effluent quality, and operational evaluation. Dilute tank waste simulant, representing a typical double-shell tank supernatant liquid layer, was concentrated from a 1.1 specific gravity to approximately 1.5 using a 4.6 m{sup 2} (50 ft{sup 2}) heated transfer area Rototherm{reg_sign} evaporator from Artisan Ind… more
Date: January 26, 2012
Creator: AR, TEDESCHI; JE, CORBETT; RA, WILSON & J, LARKIN
Partner: UNT Libraries Government Documents Department
open access

Measurement of the angular distribution of electrons from W {right arrow} e{nu} decays observed in p pbar collisions at {squareroot}s = 1.8 TeV

Description: We present a preliminary measurement of the electron angular distribution parameter {alpha}<sub>2</sub> in W {yields} e{nu} events using data collected by the D0 detector during the 1994-1995 Tevatron run. We compare our results with next-to- leading order perturbative QCD, which predicts an angular distribution of (1±{alpha}<sub>1</sub> cos{theta}* +{alpha}<sub>2</sub> cos²{theta}*), where {theta}* is the angle between the charged lepton and the antiproton in the Collins-Soper frame. In the pr… more
Date: July 26, 1999
Creator: Abbott, B.
Partner: UNT Libraries Government Documents Department
open access

Middleware for Astronomical Data Analysis Pipelines

Description: In this paper the authors describe the approach to research, develop, and evaluate prototype middleware tools and architectures. The developed tools can be used by scientists to compose astronomical data analysis pipelines easily. They use the SuperMacho data pipelines as example applications to test the framework. they describe their experience from scheduling and running these analysis pipelines on massive parallel processing machines. they use MCR a Linux cluster machine with 1152 nodes and … more
Date: January 26, 2005
Creator: Abdulla, G.; Liu, D.; Garlick, J.; Miller, M.; Nikolaev, S.; Cook, K. et al.
Partner: UNT Libraries Government Documents Department
open access

Simulation of the Future LSST Data Pipelines

Description: In this paper we describe our approach to build a pipeline simulator for the future Large-scale Synoptic Survey Telescope (LSST). The simulated pipeline will be used to research and evaluate software architectures that are efficient and flexible. It will also be used to define the real-time software and hardware requirements needed to support the anticipated LSST data rates. The LSST data pipeline requirements are still being defined, however, previous surveys can provide a good source for data… more
Date: July 26, 2004
Creator: Abdulla, Ghaleb M.
Partner: UNT Libraries Government Documents Department
open access

Interface Characterization Techniques for 304L Stainless Steel Resistance Upset Welds

Description: In an effort to better characterize and classify austenitic stainless steel resistance upset welds, standard methods have been examined and alternative methods investigated. Optical microscopy yields subjective classification due to deformation obscured bond lines and individual perception. The use of specimen preparations that better reveal grain boundaries aids in substantiating optical information. Electron microscopy techniques produce quantitative information in relation to microstructural… more
Date: July 26, 1998
Creator: Abeln, Terri G.; Kackenko, E. Jim; Necker, Carl T. & Field, Robert D.
Partner: UNT Libraries Government Documents Department
open access

A study of the elasticity of Ta at high temperature and pressure

Description: The thermodynamic and transport properties of crystals and fluids at high temperature and pressure play a central role in the Earth and planetary sciences as well as in a variety of technologies and constitute a principal probe into the internuclear potential energy function at high density. Observation of surface waves by coherent time-domain optical spectroscopy provides an experimental approach to the determination, in the diamond-anvil high-pressure cell, of the elastic constants and therma… more
Date: August 26, 1998
Creator: Abramson, E H; Brown, J M; Hansen, D W; Ruddle, C M; Slutsky, L J & Zaug, J M
Partner: UNT Libraries Government Documents Department
open access

Insulated Pressure Vessels for Vehicular Hydrogen Storage: Analysis and Performance Evaluation

Description: Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH{sub 2}) or ambient-temperature compressed hydrogen (CH{sub 2}). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (fuel flexibility, lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The work described here is directed at verifying that commercially available pressure vessels can… more
Date: June 26, 2001
Creator: Aceves, S. M.; Martinez-Frias, J.; Garcia-Villazana, O. & Espinosa-Loza, F.
Partner: UNT Libraries Government Documents Department
open access

Results of applying a non-evaporative mitigation technique to laser-initiated surface damage on fused-silica

Description: We present results from a study to determine an acceptable CO{sub 2} laser-based non-evaporative mitigation protocol for use on surface damage sites in fused-silica optics. A promising protocol is identified and evaluated on a set of surface damage sites created under ICF-type laser conditions. Mitigation protocol acceptability criteria for damage re-initiation and growth, downstream intensification, and residual stress are discussed. In previous work, we found that a power ramp at the end of t… more
Date: October 26, 2010
Creator: Adams, J. J.; Bolourchi, M.; Bude, J. D.; Guss, G. M.; Matthews, M. J. & Nostrand, M. C.
Partner: UNT Libraries Government Documents Department
open access

A New Dynamical Diffraction-Based Technique of the Residual Stress Measurements in Thin Films

Description: The recently discovered dynamical diffraction effect ''neutron camel'' was used for the residual stress measurements in a thick Si(111) crystal coated with a 2000 {angstrom} thick Ni film. The observed asymmetry of the back-face rocking curve corresponds to the bending radius of {approx} 19 km and the tension force applied to the Ni film is {approx} 90 N/m. Relative deformation of the Si crystallographic cells in the vicinity of diffractive surfaces is |{partial_derivative}u{sub z}/{partial_der… more
Date: July 26, 2001
Creator: Agamalian, M.
Partner: UNT Libraries Government Documents Department
open access

High-Level Waste Melter Review

Description: The U.S. Department of Energy (DOE) is faced with a massive cleanup task in resolving the legacy of environmental problems from years of manufacturing nuclear weapons. One of the major activities within this task is the treatment and disposal of the extremely large amount of high-level radioactive (HLW) waste stored at the Hanford Site in Richland, Washington. The current planning for the method of choice for accomplishing this task is to vitrify (glassify) this waste for disposal in a geologic… more
Date: February 26, 2002
Creator: Ahearne, J.; Gentilucci, J.; Pye, L. D.; Weber, T.; Woolley, F.; Machara, N. P. et al.
Partner: UNT Libraries Government Documents Department
open access

Industrial Complex for Solid Radwaste Management at Chernobyle Nuclear Power Plant

Description: In the framework of the preparation for the decommissioning of the Chernobyl Nuclear Power Plant (ChNPP) an Industrial Complex for Solid Radwaste Management (ICSRM) will be built under the EC TACIS Program in the vicinity of ChNPP. The paper will present the proposed concepts and their integration into existing buildings and installations. Further, the paper will consider the safety cases, as well as the integration of Western and Ukrainian Organizations into a cohesive project team and the req… more
Date: February 26, 2002
Creator: Ahner, S. & Fomin, V. V.
Partner: UNT Libraries Government Documents Department
open access

Characterizing Composition Modulations in InAs/AIAs Short-Period Superlattices

Description: The formation of quantum wires has much interest due to their novel electronic properties which may lead to enhanced optoelectronic device performance and greater photovoltaic efficiencies. One method of forming these structures is through spontaneous lateral modulation found during the epitaxial growth of III/V alloys. In this paper, we report and summarize our investigations on the formation of lateral moduation in the MBE grown InAlAs/InP(001) system. This system was grown as a short-period … more
Date: April 26, 1999
Creator: Ahrenkiel, S. P.; Follstaedt, D. M.; Jones, E. D.; Lee, S. R.; Mascarenhas, A.; Mirecki-Millunchick, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Energy effects of heat-island reduction strategies in Toronto,Canada

Description: The effect of heat-island reduction (HIR) strategies on annual energy savings and peak-power avoidance of the building sector of the Greater Toronto Area is calculated, using an hourly building energy simulation model. Results show that ratepayers could realize potential annual energy savings of over $11M from the effects of HIR strategies. The residential sector accounts for over half (59%) of the total savings, offices 13% and retail stores 28%. Savings from cool roofs are about 20%, shade tr… more
Date: August 26, 2003
Creator: Akbari, Hashem & Konopacki, Steven
Partner: UNT Libraries Government Documents Department
open access

Evaporative Evolution of Brines from Synthetic Topoah Spring Tuff Pore Water, Yucca Mountain, NV

Description: We are investigating the evaporation of pore water representative of the designated high-level-nuclear-waste repository at Yucca Mountain, NV to predict the range of brine compositions that may contact waste containers. These brines could form potentially corrosive thin films on the containers and impact their long-term integrity. Here we report the geochemistry of a relatively complex synthetic Topopah Spring Tuff pore water that was progressively evaporated in a series of experiments. The exp… more
Date: November 26, 2002
Creator: Alai, M & Carroll, S
Partner: UNT Libraries Government Documents Department
open access

GUT implications from neutrino mass

Description: An overview is given of the experimental neutrino mixing results and types of neutrino models proposed, with special attention to the general features of various GUT models involving intra-family symmetries and horizontal flavor symmetries. Many of the features are then illustrated by a specific SO (10) SUSY GUT model formulated by S.M. Barr and the author which can explain all four types of solar neutrino mixing solutions by various choices of the right-handed Majorana mass matrix. The quantit… more
Date: June 26, 2001
Creator: Albright, Carl H.
Partner: UNT Libraries Government Documents Department
open access

Undulator-Based Production of Polarized Positrons

Description: No Description Available.
Date: May 26, 2009
Creator: Alexander, Gideon; Barley, John; Batygin, Yuri; Berridge, Steven; Bharadwaj, Vinod; Bower, Gary et al.
Partner: UNT Libraries Government Documents Department
open access

Subsurface imaging using the spectral polarization difference technique and NIR illumination

Description: A subsurface imaging system is utilized to test the ability of the spectral polarization difference imaging technique for deep subsurface imaging in tissues. The illumination of the system is derived from compact class III lasers in the red and NIR spectral region and, alternatively, from a white light source and selection of the appropriate illumination wavelength using band-pass optical filters. The experimental results demonstrate detection and imaging of a high-scattering object located up … more
Date: January 26, 1999
Creator: Alfano, R R; Demos, S G & Radousky, H B
Partner: UNT Libraries Government Documents Department
open access

Beam Tilt and Angular Dispersion in Broad-Bandwidth, Nanosecond Optical Parametric Oscillators

Description: We show that the signal and idler beams generated by certain types of unseeded, nanosecond optical parametric oscillators are tilted and angularly dispersed and have anomalously large bandwidths. This effect is demonstrated in both laboratory measurements and a numerical model. We show how the optical cavity design influences the tilts and how they can be eliminated or minimized. We also determine the conditions necessary to injection seed these parametric oscillators.
Date: January 26, 1999
Creator: Alford, W. J.; Arisholm, G.; Gehr, R. J.; Schmitt, R. L. & A.V., Smith.
Partner: UNT Libraries Government Documents Department
open access

Recommendation for Supplemental Technologies for Hanford River Protection Project Potential Mission Acceleration (RPP-11838)

Description: In May of 2002, the River Protection Project at Hanford proposed as part of the accelerated cleanup for the entire Hanford Site to ''accelerate waste stabilization by developing and deploying alternative treatment and immobilization solutions that are aligned with the waste characteristics to add assurance that overall waste treatment/immobilization will be completed 20 or more years sooner.'' This paper addresses one of these elements: development of recommendations for the supplemental techno… more
Date: February 26, 2003
Creator: Allen, D. I.; Raymond, R. E.; Group, CH2M Hill Hanford; Brouns, T. M.; Choho, A. F.; Corporation, Numatec Hanford et al.
Partner: UNT Libraries Government Documents Department
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