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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 typical of technetium nitrosyl compounds, and electron spin resonance spectroscopy is consistent with a the d{sup 5} Tc(II) nitrosyl complex. The nitrosyl source is generally AHA, but may be augmented by products of reaction with nitric acid. The resulting low-valency trans-aquonitrosyl(diacetohydroxamic)-technetium(II) complex (1) is highly soluble in water, extremely hydrophilic, and is not extracted by tri-n-butylphosphate in a dodecane diluent. Its extraction properties are not pH-dependent; titration studies indicate a single species from pH 4.5 down to -0.6 (calculated). This molecule is resistant to oxidation by H{sub 2}O{sub 2}, even at high pH, and can undergo substitution to form other technetium nitrosyl complexes. The formation of 1 may strongly impact the fate of technetium in the nuclear fuel cycle.
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.
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 matching arrangement has lower efficiency than a single crystal of the same total length but gives a broader second harmonic bandwidth. The walk off compensated arrangement gives both higher conversion efficiency and broader bandwidth than a single crystal. At high irradiance, both multicrystal arrangements improve on the single crystal efficiency while maintaining broad bandwidth.
Date: July 26, 2000
Creator: ALFORD,WILLIAM J. & SMITH,ARLEE V.
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 Industries. The condensed evaporator vapor stream was collected and sampled validating efficient separation of the water. An overall decontamination factor of 1.2E+06 was achieved demonstrating excellent retention of key radioactive species within the concentrated liquid stream. The evaporator system was supported by a modular steam supply, chiller, and control computer systems which would be typically implemented at the tank farms. Operation of these support systems demonstrated successful integration while identifying areas for efficiency improvement. Overall testing effort increased the maturation of this technology to support final deployment design and continued project implementation.
Date: January 26, 2012
Creator: AR, TEDESCHI; JE, CORBETT; RA, WILSON & J, LARKIN
open access

Fundamental studies of fusion plasmas

Description: The major portion of this program is devoted to critical ICH phenomena. The topics include edge physics, fast wave propagation, ICH induced high frequency instabilities, and a preliminary antenna design for Ignitor. This research was strongly coordinated with the world's experimental and design teams at JET, Culham, ORNL, and Ignitor. The results have been widely publicized at both general scientific meetings and topical workshops including the speciality workshop on ICRF design and physics sponsored by Lodestar in April 1992. The combination of theory, empirical modeling, and engineering design in this program makes this research particularly important for the design of future devices and for the understanding and performance projections of present tokamak devices. Additionally, the development of a diagnostic of runaway electrons on TEXT has proven particularly useful for the fundamental understanding of energetic electron confinement. This work has led to a better quantitative basis for quasilinear theory and the role of magnetic vs. electrostatic field fluctuations on electron transport. An APS invited talk was given on this subject and collaboration with PPPL personnel was also initiated. Ongoing research on these topics will continue for the remainder fo the contract period and the strong collaborations are expected to continue, enhancing both the relevance of the work and its immediate impact on areas needing critical understanding.
Date: May 26, 1992
Creator: Aamodt, R. E.; Catto, P. J.; D'Ippolito, D. A.; Myra, J. R. & Russell, D. A.
open access

Fundamental studies of fusion plasmas. Annual performance report

Description: The major portion of this program is devoted to critical ICH phenomena. The topics include edge physics, fast wave propagation, ICH induced high frequency instabilities, and a preliminary antenna design for Ignitor. This research was strongly coordinated with the world`s experimental and design teams at JET, Culham, ORNL, and Ignitor. The results have been widely publicized at both general scientific meetings and topical workshops including the speciality workshop on ICRF design and physics sponsored by Lodestar in April 1992. The combination of theory, empirical modeling, and engineering design in this program makes this research particularly important for the design of future devices and for the understanding and performance projections of present tokamak devices. Additionally, the development of a diagnostic of runaway electrons on TEXT has proven particularly useful for the fundamental understanding of energetic electron confinement. This work has led to a better quantitative basis for quasilinear theory and the role of magnetic vs. electrostatic field fluctuations on electron transport. An APS invited talk was given on this subject and collaboration with PPPL personnel was also initiated. Ongoing research on these topics will continue for the remainder fo the contract period and the strong collaborations are expected to continue, enhancing both the relevance of the work and its immediate impact on areas needing critical understanding.
Date: May 26, 1992
Creator: Aamodt, R. E.; Catto, P. J.; D`Ippolito, D. A.; Myra, J. R. & Russell, D. A.
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 presence of QCD corrections, the parameters {alpha}<sub>1</sub> and {alpha}<sub>2</sub> become functions of p<sup>W</sup><sub>T</sub> , the W boson transverse momentum. We present the first measurement of {alpha}<sub>2</sub> as a function of p<sup>W</sup><sub>T</sub>. This measurement is of importance, because it provides a test of next-to-leading order QCD corrections which are a non-negligible contribution to the W mass measurement.
Date: July 26, 1999
Creator: Abbott, B.
open access

The drag of two streamline bodies as affected by protuberances and appendages

Description: This report presents the results of wind tunnel tests of two airship models conducted to determine the drag coefficients at zero pitch, and the effect of fins and cars and of flat and streamlined protuberances located at various positions along the hull. During the investigation the stern of one model was rounded off to produce a blunter shape. The extreme range of the Reynolds number based on the over-all length of the models was from 1,300,000 to 33,000,000. At large values of the Reynolds number the streamlined protuberance affected the drag very little, and the additional drag caused by the flat protuberance was less than the calculated drag by the protuberance alone. The fins and cars together increased the bare-hull drag about 20 per cent.
Date: September 26, 1932
Creator: Abbott, Ira H.
open access

Growth of molten core debris pools in concrete. Part II. A. Pool growth in composite beds; B. Effect of overlaying steel layers. Final report, March 1, 1978-September 30, 1979. [LMFBR]

Description: The heat and mass transfer processes taking place in molten core debris/concrete systems have been experimentally investigated. Two types of experiments have been conducted. The first experiment simulates the growth of a molten debris pool in a composite sacrificial bed. This experiment models debris pool growth in an inner, low-melting point, sacrificial material zone followed by a melting attack on the concrete bed. The purpose of the inner zone is to quickly melt and dilute the debris pool so that its subsequent downward growth in the concrete may be slowed. In the second experiment a two-layer immiscible liquid system is volumetrically heated and allowed to melt into a low-density gas releasing solid bed which is miscible in the initially-higher-density bottom liquid. The solid melts, mixes with, and dilutes the bottom liquid pool until its density is lower than that of the top liquid.
Date: December 26, 1979
Creator: Abdel-Khalik, S I
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 Luster parallel file system as the hardware test-bed to test and enhance the scalability of the tools.
Date: January 26, 2005
Creator: Abdulla, G.; Liu, D.; Garlick, J.; Miller, M.; Nikolaev, S.; Cook, K. et al.
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 requirements. Our approach is to use the SuperMacho data pipeline as a prototyping tool to identify a framework for building Modular Data-Centric Pipeline (MDCP) architectures. The prototyping is done in a hierarchical fashion to help capture and define the general data attributes (schema) first. We then model other necessary components based on science and performance requirements. We use identified schemas or data attributes as a way to define a data model for LSST.
Date: July 26, 2004
Creator: Abdulla, Ghaleb M.
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 constituents. Orientation Imaging Microscopy (OIM) is a relatively new technique for obtaining objective, quantitative information pertaining to weld integrity, i.e., percent grain boundary growth across the interface.
Date: July 26, 1998
Creator: Abeln, T.G.; Kackenko, E.J.; Necker, C.T. & Field, R.D.
open access

Use of a General Nonlinear Least-Squares Curve Fitting Program With Nonclosed Form Relationships. [GNLS, in FORTRAN for CDC Computers]

Description: A use for GNLS, a general nonlinear least-squares curve fitting program, is presented. In this use GNLS determines a set of best parameters for relationships that cannot be written in closed form. This program can be useful for experimenters who need to determine experimental parameters by fitting nonclosed-form relationships to experimental data. Two examples are given to indicate how GNLS can be used for this type of problem. 11 figures.
Date: December 26, 1979
Creator: Abey, A. E.
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 thermal diffusivity of metal crystals as well as the equation of state and thermal transport properties of fluids. The electrical resistivities of metals may also be approximately accessible via the Wiedemann Franz Law. Preliminary results on Ta to pressures of 5.2 GPa are reported here. [Ta, elasticity, sound velocity, thermal diffusivity, equation of state].
Date: August 26, 1998
Creator: Abramson, E H; Brown, J M; Hansen, D W; Ruddle, C M; Slutsky, L J & Zaug, J M
open access

Final Scientific Report

Description: Viscosities of water, nitrogen and carbon dioxide have been measured at elevated pressures and temperatures in the diamond-anvil cell. A strong correlation between viscosity and entropy has been confirmed.
Date: June 26, 2009
Creator: Abramson, Evan
open access

Thermal Decomposition of Radiation-Damaged Polystyrene

Description: The radiation-damaged polystyrene (given the identification name of 'polycube') was fabricated by mixing high-density polystyrene material ("Dylene Fines # 100") with plutonium and uranium oxides. The polycubes were used in the 1960s for criticality studies during processing of spent nuclear fuel. The polycubes have since been stored for almost 40 years at the Hanford Plutonium Finishing Plant (PFP) after failure of two processes to reclaim the plutonium and uranium oxides from the polystyrene matrix. Thermal decomposition products from this highly cross-linked polystyrene matrix were characterized using Gas Chromatograph/Mass Spectroscopy (GC/MS) system coupled to a horizontal furnace. The decomposition studies were performed in air and helium atmospheres at about 773 K. The volatile and semi-volatile organic products for the radiation-damaged polystyrene were different compared to virgin polystyrene. The differences were in the number of organic species generated and their concentrations. In the inert (i.e., helium) atmosphere, the major volatile organic products identified (in order of decreasing concentrations) were styrene, benzene, toluene, ethylbenzene, xylene, nathphalene, propane, .alpha.-methylbenzene, indene and 1,2,3-trimethylbenzene. But in air, the major volatile organic species identified changed slightly. Concentrations of the organic species in the inert atmosphere were significantly higher than those for the air atmosphere processing. Overall, 38 volatile organic species were identified in the inert atmosphere compared to 49 species in air. Twenty of the 38 species in the inert conditions were also products in the air atmosphere. Twenty-two oxidized organic products were identified during thermal processing in air.
Date: September 26, 2000
Creator: Abrefah, John & Klinger, George S.
open access

Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst

Description: The work performed in the program suggests that cobalt catalytic performance is a complex function of crystallite size, crystallite composition, and cobalt-support interaction. These properties are determined by the nature of support, the bimetallic component, the promoters, and the method of preparation. Results so far indicate that the lowest methane selectivity occurs on support No. 8, and the highest activity is obtained on support No. 10. Also, promoters 2 and 3 may help lower the formation of methane. These findings, along with the catalyst knowledge gained during Union Carbide's former contract AC22-84PC70028, will be used to develop a superior cobalt catalyst.
Date: August 26, 1992
Creator: Abrevaya, H.
open access

Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst. Technical progress report No. 9, October 1, 1991--December 31, 1991

Description: The work performed in the program suggests that cobalt catalytic performance is a complex function of crystallite size, crystallite composition, and cobalt-support interaction. These properties are determined by the nature of support, the bimetallic component, the promoters, and the method of preparation. Results so far indicate that the lowest methane selectivity occurs on support No. 8, and the highest activity is obtained on support No. 10. Also, promoters 2 and 3 may help lower the formation of methane. These findings, along with the catalyst knowledge gained during Union Carbide`s former contract AC22-84PC70028, will be used to develop a superior cobalt catalyst.
Date: August 26, 1992
Creator: Abrevaya, H.
open access

EARLY ENTRANCE COPRODUCTION PLANT

Description: The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstock. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing Plan (RD and T) for implementation in Phase II. The objective of Phase II is to implement the RD and T as outlined in the Phase I RD and T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and other feedstocks. The objective of Phase III is to develop an engineering design package and a financing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information that will be needed to move the EECP forward to detailed design, construction, and operation by industry.
Date: October 26, 2000
Creator: Abughazaleh, John S.; Ahmed, Mushtaq; Anand, Ashok; Anderson, John H.; Benham, Charles; Brent, Fred D. et al.
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 be safely used to store liquid hydrogen. The use of commercially available pressure vessels significantly reduces the cost and complexity of the insulated pressure vessel development effort. This paper describes a series of tests that have been done with aluminum-lined, fiber-wrapped vessels to evaluate the damage caused by low temperature operation. All analysis and experiments to date indicate that no significant damage has resulted. Required future tests are described that will prove that no technical barriers exist to the safe use of aluminum-fiber vessels at cryogenic temperatures. Future activities also include a demonstration project in which the insulated pressure vessels will be installed and tested on two vehicles. A draft standard will also be generated for obtaining certification for insulated pressure vessels.
Date: June 26, 2001
Creator: Aceves, S. M.; Martinez-Frias, J.; Garcia-Villazana, O. & Espinosa-Loza, F.
open access

Monitoring the Migrations of Wild Snake River Spring/Summer Chinook Salmon Juveniles, 2007-2008 Report of Research.

Description: This report provides results from an ongoing project to monitor the migration behavior and survival of wild juvenile spring/summer Chinook salmon in the Snake River Basin. Data reported is from detections of PIT tagged fish during late summer 2007 through mid-2008. Fish were tagged in summer 2007 by the National Marine Fisheries Service (NMFS) in Idaho and by the Oregon Department of Fish and Wildlife (ODFW) in Oregon. Our analyses include migration behavior and estimated survival of fish at instream PIT-tag monitors and arrival timing and estimated survival to Lower Granite Dam. Principal results from tagging and interrogation during 2007-2008 are listed below: (1) In July and August 2007, we PIT tagged and released 7,390 wild Chinook salmon parr in 12 Idaho streams or sample areas. (2) Overall observed mortality from collection, handling, tagging, and after a 24-hour holding period was 1.4%. (3) Of the 2,524 Chinook salmon parr PIT tagged and released in Valley Creek in summer 2007, 218 (8.6%) were detected at two instream PIT-tag monitoring systems in lower Valley Creek from late summer 2007 to the following spring 2008. Of these, 71.6% were detected in late summer/fall, 11.9% in winter, and 16.5% in spring. Estimated parr-to-smolt survival to Lower Granite Dam was 15.5% for the late summer/fall group, 48.0% for the winter group, and 58.5% for the spring group. Based on detections at downstream dams, the overall efficiency of VC1 (upper) or VC2 (lower) Valley Creek monitors for detecting these fish was 21.1%. Using this VC1 or VC2 efficiency, an estimated 40.8% of all summer-tagged parr survived to move out of Valley Creek, and their estimated survival from that point to Lower Granite Dam was 26.5%. Overall estimated parr-to-smolt survival for all summer-tagged parr from this stream at the dam was 12.1%. Development and improvement of instream …
Date: May 26, 2009
Creator: Achord, Stephen; Sandford, Benjamin P. & Hockersmith, Eric E.
open access

Legislative Prayer and School Prayer: The Constitutional Difference

Description: The Supreme Court's decisions holding government-sponsored prayer in the public schools to violate the First Amendment's establishment clause but prayer in legislative assemblies to be constitutional are sometimes lifted up as contradictory. This report summarizes the relevant decisions and identifies the distinctions the Court has drawn between the two situations.
Date: October 26, 1994
Creator: Ackerman, David A.
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