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DESTRUCTION OF TETRAPHENYLBORATE IN TANK 48H USING WET AIR OXIDATION BATCH BENCH SCALE AUTOCLAVE TESTING WITH ACTUAL RADIOACTIVE TANK 48H WASTE (open access)

DESTRUCTION OF TETRAPHENYLBORATE IN TANK 48H USING WET AIR OXIDATION BATCH BENCH SCALE AUTOCLAVE TESTING WITH ACTUAL RADIOACTIVE TANK 48H WASTE

Wet Air Oxidation (WAO) is one of the two technologies being considered for the destruction of Tetraphenylborate (TPB) in Tank 48H. Batch bench-scale autoclave testing with radioactive (actual) Tank 48H waste is among the tests required in the WAO Technology Maturation Plan. The goal of the autoclave testing is to validate that the simulant being used for extensive WAO vendor testing adequately represents the Tank 48H waste. The test objective was to demonstrate comparable test results when running simulated waste and real waste under similar test conditions. Specifically: (1) Confirm the TPB destruction efficiency and rate (same reaction times) obtained from comparable simulant tests, (2) Determine the destruction efficiency of other organics including biphenyl, (3) Identify and quantify the reaction byproducts, and (4) Determine off-gas composition. Batch bench-scale stirred autoclave tests were conducted with simulated and actual Tank 48H wastes at SRNL. Experimental conditions were chosen based on continuous-flow pilot-scale simulant testing performed at Siemens Water Technologies Corporation (SWT) in Rothschild, Wisconsin. The following items were demonstrated as a result of this testing. (1) Tetraphenylborate was destroyed to below detection limits during the 1-hour reaction time at 280 C. Destruction efficiency of TPB was > 99.997%. (2) Other organics (TPB …
Date: March 31, 2009
Creator: Adu-Wusu, K & Paul Burket, P
Object Type: Report
System: The UNT Digital Library
Timelike Virtual Compton Scattering from Electron-Positron Radiative Annihilation (open access)

Timelike Virtual Compton Scattering from Electron-Positron Radiative Annihilation

We propose measurements of the deeply virtual Compton amplitude (DVCS) {gamma}* {yields} H{bar H}{gamma} in the timelike t = (p{sub H} + p{sub {bar H}}){sup 2} > 0 kinematic domain which is accessible at electron-positron colliders via the radiative annihilation process e{sup +}e{sup -} {yields} H{bar H}{gamma}. These processes allow the measurement of timelike deeply virtual Compton scattering for a variety of H{bar H} hadron pairs such as {pi}{sup +}{pi}{sup -}, K{sup +}K{sup -}, and D{bar D} as well as p{bar p}. As in the conventional spacelike DVCS, there are interfering coherent amplitudes contributing to the timelike processes involving C = - form factors. The interference between the amplitudes measures the phase of the C = + timelike DVCS amplitude relative to the phase of the timelike form factors and can be isolated by considering the forward-backward e{sup +} {leftrightarrow} e{sup -} asymmetry. The J = 0 fixed pole contribution which arises from the local coupling of the two photons to the quark current plays a special role. As an example we present a simple model.
Date: March 31, 2009
Creator: Afanasev, Andrei; Brodsky, Stanley J.; Carlson, Carl E. & Mukherjee, Asmita
Object Type: Article
System: The UNT Digital Library
Clean Coal Program Research Activities (open access)

Clean Coal Program Research Activities

Although remarkable progress has been made in developing technologies for the clean and efficient utilization of coal, the biggest challenge in the utilization of coal is still the protection of the environment. Specifically, electric utilities face increasingly stringent restriction on the emissions of NO{sub x} and SO{sub x}, new mercury emission standards, and mounting pressure for the mitigation of CO{sub 2} emissions, an environmental challenge that is greater than any they have previously faced. The Utah Clean Coal Program addressed issues related to innovations for existing power plants including retrofit technologies for carbon capture and sequestration (CCS) or green field plants with CCS. The Program focused on the following areas: simulation, mercury control, oxycoal combustion, gasification, sequestration, chemical looping combustion, materials investigations and student research experiences. The goal of this program was to begin to integrate the experimental and simulation activities and to partner with NETL researchers to integrate the Program's results with those at NETL, using simulation as the vehicle for integration and innovation. The investigators also committed to training students in coal utilization technology tuned to the environmental constraints that we face in the future; to this end the Program supported approximately 12 graduate students toward the completion …
Date: March 31, 2009
Creator: Baxter, Larry; Eddings, Eric; Fletcher, Thomas; Kelly, Kerry; Lighty, JoAnn; Pugmire, Ronald et al.
Object Type: Report
System: The UNT Digital Library
Temporary Restoration of Bull Trout Passage at Albeni Falls Dam, 2008 Progress Report. (open access)

Temporary Restoration of Bull Trout Passage at Albeni Falls Dam, 2008 Progress Report.

The goal of this project is to provide temporary upstream passage of bull trout around Albeni Falls Dam on the Pend Oreille River, Idaho. Our specific objectives are to capture fish downstream of Albeni Falls Dam, tag them with combination acoustic and radio transmitters, release them upstream of Albeni Falls Dam, and determine if genetic information on tagged fish can be used to accurately establish where fish are located during the spawning season. In 2007, radio receiving stations were installed at several locations throughout the Pend Oreille River watershed to detect movements of adult bull trout; however, no bull trout were tagged during that year. In 2008, four bull trout were captured downstream of Albeni Falls Dam, implanted with transmitters, and released upstream of the dam at Priest River, Idaho. The most-likely natal tributaries of bull trout assigned using genetic analyses were Grouse Creek (N = 2); a tributary of the Pack River, Lightning Creek (N = 1); and Rattle Creek (N = 1), a tributary of Lightning Creek. All four bull trout migrated upstream from the release site in Priest River, Idaho, were detected at monitoring stations near Dover, Idaho, and were presumed to reside in Lake Pend Oreille …
Date: March 31, 2009
Creator: Bellgraph, Brian J.
Object Type: Report
System: The UNT Digital Library
HEAVY ION FUSION SCIENCE VIRTUALNATIONAL LABORATORY 2nd QUARTER 2009 MILESTONE REPORT: Perform beam and target experiments with a new induction bunching module, extended FEPS plasma, and improved target diagnostic and positioning equipment on NDCX (open access)

HEAVY ION FUSION SCIENCE VIRTUALNATIONAL LABORATORY 2nd QUARTER 2009 MILESTONE REPORT: Perform beam and target experiments with a new induction bunching module, extended FEPS plasma, and improved target diagnostic and positioning equipment on NDCX

This effort contains two main components: The new induction-bunching module is expected to deliver higher fluence in the bunched beam, and the new target positioner will enable a significantly enhanced target physics repetition rate. The velocity ramp that bunches the K{sup +} beam in the neutralized drift compression section is established with a bipolar voltage ramp applied to an acceleration gap. An induction acceleration module creates this voltage waveform. The new bunching module (IBM) specially built for NDCX has approximately twice the capability (volt-seconds) as our original IBM. We reported on the beam line design for the best use of the bunching module in our FY08 Q2 report. Based on simulations and theoretical work, we chose to extend the drift compression section and use the additional volt-seconds to extend the pulse duration and keep the peak voltage swing (and velocity excursions) similar to the present module. Simulations showed that this approach, which extends the drift section, to be advantageous because it limits the chromatic aberrations in the beam spot on target. To this end, colleagues at PPPL have fabricated the meter-long extension to the ferroelectric plasma source and it was installed on the beam line with the new IBM in …
Date: March 31, 2009
Creator: Bieniosek, F. M.; Anders, A.; Barnard, J. J.; Dickinson, M. R.; Gilson, E.; Greenway, W. et al.
Object Type: Report
System: The UNT Digital Library
Perry Daily Journal (Perry, Okla.), Vol. 117, No. 63, Ed. 1 Tuesday, March 31, 2009 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 117, No. 63, Ed. 1 Tuesday, March 31, 2009

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: March 31, 2009
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Altus Times (Altus, Okla.), Vol. 111, No. 189, Ed. 1 Tuesday, March 31, 2009 (open access)

The Altus Times (Altus, Okla.), Vol. 111, No. 189, Ed. 1 Tuesday, March 31, 2009

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 31, 2009
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Synthesis and Optimization of the Sintering Kinetics of Actinide Nitrides (open access)

Synthesis and Optimization of the Sintering Kinetics of Actinide Nitrides

Research conducted for this NERI project has advanced the understanding and feasibility of nitride nuclear fuel processing. In order to perform this research, necessary laboratory infrastructure was developed; including basic facilities and experimental equipment. Notable accomplishments from this project include: the synthesis of uranium, dysprosium, and cerium nitrides using a novel, low-cost mechanical method at room temperature; the synthesis of phase pure UN, DyN, and CeN using thermal methods; and the sintering of UN and (Ux, Dy1-x)N (0.7 ≤ X ≤ 1) pellets from phase pure powder that was synthesized in the Advanced Materials Laboratory at Boise State University.
Date: March 31, 2009
Creator: Butt, Drryl P. & Jaques, Brian
Object Type: Report
System: The UNT Digital Library
Desalination: Status and Federal Issues (open access)

Desalination: Status and Federal Issues

This report is categorized into three categories: (I) Desalination: The Federal Policy Context, (II) Desalination Adoption in the United States and (III) Federal Desalination Research.
Date: March 31, 2009
Creator: Carter, Nicole T.
Object Type: Report
System: The UNT Digital Library
The Boerne Star (Boerne, Tex.), Vol. 103, No. 26, Ed. 1 Tuesday, March 31, 2009 (open access)

The Boerne Star (Boerne, Tex.), Vol. 103, No. 26, Ed. 1 Tuesday, March 31, 2009

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: March 31, 2009
Creator: Cartwright, Brian & Velvin, Candace E.
Object Type: Newspaper
System: The Portal to Texas History
Exact Lattice Supersymmetry (open access)

Exact Lattice Supersymmetry

We provide an introduction to recent lattice formulations of supersymmetric theories which are invariant under one or more real supersymmetries at nonzero lattice spacing. These include the especially interesting case of N = 4 SYM in four dimensions. We discuss approaches based both on twisted supersymmetry and orbifold-deconstruction techniques and show their equivalence in the case of gauge theories. The presence of an exact supersymmetry reduces and in some cases eliminates the need for fine tuning to achieve a continuum limit invariant under the full supersymmetry of the target theory. We discuss open problems.
Date: March 31, 2009
Creator: Catterall, Simon; Kaplan, David B. & Unsal, Mithat
Object Type: Article
System: The UNT Digital Library
Exceptional groups, symmetric spaces and applications (open access)

Exceptional groups, symmetric spaces and applications

In this article we provide a detailed description of a technique to obtain a simple parameterization for different exceptional Lie groups, such as G{sub 2}, F{sub 4} and E{sub 6}, based on their fibration structure. For the compact case, we construct a realization which is a generalization of the Euler angles for SU(2), while for the non compact version of G{sub 2(2)}/SO(4) we compute the Iwasawa decomposition. This allows us to obtain not only an explicit expression for the Haar measure on the group manifold, but also for the cosets G{sub 2}/SO(4), G{sub 2}/SU(3), F{sub 4}/Spin(9), E{sub 6}/F{sub 4} and G{sub 2(2)}/SO(4) that we used to find the concrete realization of the general element of the group. Moreover, as a by-product, in the simplest case of G{sub 2}/SO(4), we have been able to compute an Einstein metric and the vielbein. The relevance of these results in physics is discussed.
Date: March 31, 2009
Creator: Cerchiai, Bianca L. & Cacciatori, Sergio L.
Object Type: Book
System: The UNT Digital Library
Scalable Methods for Electronic Excitations and Optical Responses in Nanostructures: Mathematics to Algorithms to Observables (open access)

Scalable Methods for Electronic Excitations and Optical Responses in Nanostructures: Mathematics to Algorithms to Observables

The work reported here took place at the University of Minnesota from September 15, 2003 to November 14, 2005. This funding resulted in 10 invited articles or book chapters, 37 articles in refereed journals and 13 invited talks. The funding helped train 5 PhD students. The research supported by this grant focused on developing theoretical methods for predicting and understanding the properties of matter at the nanoscale. Within this regime, new phenomena occur that are characteristic of neither the atomic limit, nor the crystalline limit. Moreover, this regime is crucial for understanding the emergence of macroscopic properties such as ferromagnetism. For example, elemental Fe clusters possess magnetic moments that reside between the atomic and crystalline limits, but the transition from the atomic to the crystalline limit is not a simple interpolation between the two size regimes. To capitalize properly on predicting such phenomena in this transition regime, a deeper understanding of the electronic, magnetic and structural properties of matter is required, e.g., electron correlation effects are enhanced within this size regime and the surface of a confined system must be explicitly included. A key element of our research involved the construction of new algorithms to address problems peculiar to the …
Date: March 31, 2009
Creator: Chelikowsky, James R.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 89, No. 88, Ed. 1 Tuesday, March 31, 2009 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 89, No. 88, Ed. 1 Tuesday, March 31, 2009

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 31, 2009
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
[Letter from Fantasy of Flight to Helen Wyatt Snapp, March 31, 2009] (open access)

[Letter from Fantasy of Flight to Helen Wyatt Snapp, March 31, 2009]

Letter from Stephanie Conner of Fantasy of Flight to Helen Snapp, thanking her for her participation in the "Living History Series celebrating the accomplishments of the Women Air Service Pilots."
Date: March 31, 2009
Creator: Conner, Stephanie
Object Type: Letter
System: The Portal to Texas History
Sugar-Based Ethanol Biorefinery: Ethanol, Succinic Acid and By-Product Production (open access)

Sugar-Based Ethanol Biorefinery: Ethanol, Succinic Acid and By-Product Production

The work conducted in this project is an extension of the developments itemized in DE-FG-36-04GO14236. This program is designed to help the development of a biorefinery based around a raw sugar mill, which in Louisiana is an underutilized asset. Some technical questions were answered regarding the addition of a biomass to ethanol facility to existing sugar mills. The focus of this work is on developing technology to produce ethanol and valuable by-products from bagasse. Three major areas are addressed, feedstock storage, potential by-products and the technology for producing ethanol from dilute ammonia pre-treated bagasse. Sugar mills normally store bagasse in a simple pile. During the off season there is a natural degradation of the bagasse, due to the composting action of microorganisms in the pile. This has serious implications if bagasse must be stored to operate a bagasse/biorefinery for a 300+ day operating cycle. Deterioration of the fermentables in bagasse was found to be 6.5% per month, on pile storage. This indicates that long term storage of adequate amounts of bagasse for year-round operation is probably not feasible. Lignin from pretreatment seemed to offer a potential source of valuable by-products. Although a wide range of phenolic compounds were present in …
Date: March 31, 2009
Creator: Day, Donal F.
Object Type: Report
System: The UNT Digital Library
Thermodynamics of the Complexation of Uranium(VI) by oxalate in aqueous solution at 10-70oC (open access)

Thermodynamics of the Complexation of Uranium(VI) by oxalate in aqueous solution at 10-70oC

The protonation reactions of oxalate (ox) and the complex formation of uranium(VI) with oxalate in 1.05 mol kg{sup -1} NaClO{sub 4} were studied at variable temperatures (10-70 C). Three U(VI)/ox complexes (UO{sub 2}ox{sub j}{sup (2-2j){sup +}} with j = 1, 2, 3) were identified in this temperature range. The formation constants and the molar enthalpies of complexation were determined by spectrophotometry and calorimetry. The complexation of uranium(VI) with oxalate ion is exothermic at lower temperatures (10-40 C) and becomes endothermic at higher temperatures (55-70 C). In spite of this, the free energy of complexation becomes more negative at higher temperatures due to increasingly more positive entropy of complexation that exceeds the increase of the enthalpy of complexation. The thermodynamic parameters at different temperatures, in conjunction with the literature data for other dicarboxylic acids, provide insight into the relative strength of U(VI) complexes with a series of dicarboxylic acids (oxalic, malonic and oxydiacetic) and rationalization for the highest stability of U(VI)/oxalate complexes in the series. The data reported in this study are of importance in predicting the migration of uranium(VI) in geological environments in the case of failure of the engineering barriers which protect waste repositories.
Date: March 31, 2009
Creator: Di Bernardo, Plinio; Zanonato, Pier Luigi; Tian, Guoxin; Tolazzi, Marilena & Rao, Linfeng
Object Type: Article
System: The UNT Digital Library
An Integrated Solid-State LED Luminaire for General Lighting (open access)

An Integrated Solid-State LED Luminaire for General Lighting

A strong systems approach to designing and building practical LED-based replacement lamps is lacking. The general method of taking high-performance LEDs and marrying them to standard printed circuit boards, drivers and a heat sink has fallen short of the promise of LED lighting. In this program, a top-down assessment of requirements and a bottom-up reinvention of LED sources, electronics, optics and mechanics have resulted in the highest performance lamp possible. The team, comprised of Color Kinetics, the leaders in LED lighting and Cree, the leaders in LED devices took an approach to reinvent the package, the driver and the overall form and aesthetic of a replacement source. The challenge was to create a new benchmark in LED lighting - the resultant lamp, a PAR38 equivalent, met the light output, color, color quality and efficacy marks set out in the program as well as being dimmable, which is important for market acceptance. The approach combined the use of multiple source die, a chip-on-board approach, a very efficient driver topology, the use of both direct emission and phosphor conversion, and a unique faceted optic to avoid the losses, artifacts and hotspots of lensed approaches. The integral heat sink provided a mechanical base …
Date: March 31, 2009
Creator: Dowling, Kevin; Lys, Fritz Morgan Ihor; Datta, Mike; Keller, Bernd & Yuan, Thomas
Object Type: Report
System: The UNT Digital Library
Continuous Energy, Multi-Dimensional Transport Calculations for Problem Dependent Resonance Self-Shielding (open access)

Continuous Energy, Multi-Dimensional Transport Calculations for Problem Dependent Resonance Self-Shielding

The overall objective of the work here has been to eliminate the approximations used in current resonance treatments by developing continuous energy multi-dimensional transport calculations for problem dependent self-shielding calculations. The work here builds on the existing resonance treatment capabilities in the ORNL SCALE code system.
Date: March 31, 2009
Creator: Downar, T.
Object Type: Report
System: The UNT Digital Library
Medical Marijuana: Review and Analysis of Federal and State Policies (open access)

Medical Marijuana: Review and Analysis of Federal and State Policies

This report discusses the issue before Congress of whether to continue the federal prosecution of medical marijuana patients and their providers, in accordance with the federal Controlled Substances Act (CSA), or whether to relax federal marijuana prohibition enough to permit the medicinal use of botanical cannabis products when recommended by a physician, especially where permitted under state law.
Date: March 31, 2009
Creator: Eddy, Mark
Object Type: Report
System: The UNT Digital Library
Well-to-wheels energy use and greenhouse gas emissions analysis of plug-in hybrid electric vehicles. (open access)

Well-to-wheels energy use and greenhouse gas emissions analysis of plug-in hybrid electric vehicles.

Researchers at Argonne National Laboratory expanded the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model and incorporated the fuel economy and electricity use of alternative fuel/vehicle systems simulated by the Powertrain System Analysis Toolkit (PSAT) to conduct a well-to-wheels (WTW) analysis of energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). The WTW results were separately calculated for the blended charge-depleting (CD) and charge-sustaining (CS) modes of PHEV operation and then combined by using a weighting factor that represented the CD vehicle-miles-traveled (VMT) share. As indicated by PSAT simulations of the CD operation, grid electricity accounted for a share of the vehicle's total energy use, ranging from 6% for a PHEV 10 to 24% for a PHEV 40, based on CD VMT shares of 23% and 63%, respectively. In addition to the PHEV's fuel economy and type of on-board fuel, the marginal electricity generation mix used to charge the vehicle impacted the WTW results, especially GHG emissions. Three North American Electric Reliability Corporation regions (4, 6, and 13) were selected for this analysis, because they encompassed large metropolitan areas (Illinois, New York, and California, respectively) and provided a significant variation of marginal generation …
Date: March 31, 2009
Creator: Elgowainy, A.; Burnham, A.; Wang, M.; Molburg, J.; Rousseau, A. & Systems, Energy
Object Type: Report
System: The UNT Digital Library
Chemical Looping Combustion Kinetics (open access)

Chemical Looping Combustion Kinetics

One of the most promising methods of capturing CO{sub 2} emitted by coal-fired power plants for subsequent sequestration is chemical looping combustion (CLC). A powdered metal oxide such as NiO transfers oxygen directly to a fuel in a fuel reactor at high temperatures with no air present. Heat, water, and CO{sub 2} are released, and after H{sub 2}O condensation the CO{sub 2} (undiluted by N{sub 2}) is ready for sequestration, whereas the nickel metal is ready for reoxidation in the air reactor. In principle, these processes can be repeated endlessly with the original nickel metal/nickel oxide participating in a loop that admits fuel and rejects ash, heat, and water. Our project accumulated kinetic rate data at high temperatures and elevated pressures for the metal oxide reduction step and for the metal reoxidation step. These data will be used in computational modeling of CLC on the laboratory scale and presumably later on the plant scale. The oxygen carrier on which the research at Utah is focused is CuO/Cu{sub 2}O rather than nickel oxide because the copper system lends itself to use with solid fuels in an alternative to CLC called 'chemical looping with oxygen uncoupling' (CLOU).
Date: March 31, 2009
Creator: Eyring, Edward & Konya, Gabor
Object Type: Text
System: The UNT Digital Library
Caustic Recycle from Hanford Tank Waste Using Large Area NaSICON Structures (LANS) (open access)

Caustic Recycle from Hanford Tank Waste Using Large Area NaSICON Structures (LANS)

This report presents the results of a 5-day test of an electrochemical bench-scale apparatus using a proprietary (NAS-GY) material formulation of a (Na) Super Ion Conductor (NaSICON) membrane in a Large Area NaSICON Structures (LANS) configuration. The primary objectives of this work were to assess system performance, membrane seal integrity, and material degradation while removing Na from Group 5 and 6 tank waste from the Hanford Site.
Date: March 31, 2009
Creator: Fountain, Matthew S.; Sevigny, Gary J.; Balagopal, S. & Bhavaraju, S.
Object Type: Report
System: The UNT Digital Library
2008 Photoions, Photoionization & Photodetachment Gordon Research Conference January 27-February 1, 2008 (open access)

2008 Photoions, Photoionization & Photodetachment Gordon Research Conference January 27-February 1, 2008

This conference brings together scientists interested in a range of basic phenomena linked to the ejection and scattering of electrons from atoms, molecules, clusters, liquids and solids by absorption of light. Photoionization, a highly sensitive probe of both structure and dynamics, can range from perturbative single-photon processes to strong-field highly non-perturbative interactions. It is responsible for the formation and destruction of molecules in astrophysical and plasma environments and successfully used in advanced analytical techniques. Positive ions, which can be produced and studied most effectively using photoionization, are the major components of all plasmas, vital constituents of flames and important intermediates in many chemical reactions. Negative ions are significant as transient species and, when photodetached, the corresponding neutral species often undergoes remarkable, otherwise non-observable, dynamics. The scope of the meeting spans from novel observations in atomic and molecular physics, such as Coulomb Crystals, highly excited states and cold Rydberg plasmas, to novel energy resolved or ultrafast time-resolved experiments, photoionization in strong laser fields, theoretical method development for electron scattering, photoionization and photodetachment and more complex phenomena such as charge transfer and DNA and protein conductivity, important for biological and analytical applications.
Date: March 31, 2009
Creator: GRay, Klaus Muller-Dethefs Nancy Ryan
Object Type: Article
System: The UNT Digital Library