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

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

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.
Object Type: Article
System: The UNT Digital Library
Arctic Energy Technology Development Laboratory (Part 2) (open access)

Arctic Energy Technology Development Laboratory (Part 2)

Methane (CH{sub 4}) in natural gas is a major energy source in the U.S., and is used extensively on Alaska's North Slope, including the oilfields in Prudhoe Bay, the community of Barrow, and the National Petroleum Reserve, Alaska (NPRA). Smaller villages, however, are dependent on imported diesel fuel for both power and heating, resulting in some of the highest energy costs in the U.S. and crippling local economies. Numerous CH{sub 4} gas seeps have been observed on wetlands near Atqasuk, Alaska (in the NPRA), and initial measurements have indicated flow rates of 3,000-5,000 ft{sup 3} day{sup -1} (60-100 kg CH{sub 4} day{sup -1}). Gas samples collected in 1996 indicated biogenic origin, although more recent sampling indicated a mixture of biogenic and thermogenic gas. In this study, we (1) quantified the amount of CH{sub 4} generated by several seeps and evaluated their potential use as an unconventional gas source for the village of Atqasuk; (2) collected gas and analyzed its composition from multiple seeps several miles apart to see if the source is the same, or if gas is being generated locally from isolated biogenic sources; and (3) assessed the potential magnitude of natural CH{sub 4} gas seeps for future use …
Date: December 31, 2008
Creator: 960443, See OSTI ID Number
Object Type: Report
System: The UNT Digital Library
Arctic Energy Technology Development Laboratory (Part 3) (open access)

Arctic Energy Technology Development Laboratory (Part 3)

Various laboratory tests were carried at the R & D facility of BJ Services in Tomball, TX with BJ Services staff to predict and evaluate the performance of the Ceramicrete slurry for its effective use in permafrost cementing operations. Although other standards such as those of the American Standard for Testing Materials (ASTM) and Construction Specification Institute (CSI) exist, all these tests were standardized by the API. A summary of the tests traditionally used in the cement slurry design as well as the API tests reference document are provided in Table 7. All of these tests were performed within the scope of this research to evaluate properties of the Ceramicrete.
Date: December 31, 2008
Creator: 960443, See OSTI ID Number
Object Type: Report
System: The UNT Digital Library
Greenidge Multi-Pollutant Control Project (Part 2) (open access)

Greenidge Multi-Pollutant Control Project (Part 2)

The digital full text of this report is divided into two parts. This part of the report contains five and a half of the twelve appendices of the report.
Date: October 18, 2008
Creator: 960446, See OSTI ID
Object Type: Report
System: The UNT Digital Library
Greenidge Multi-Pollutant Control Project (Part 3) (open access)

Greenidge Multi-Pollutant Control Project (Part 3)

None
Date: October 18, 2008
Creator: 960446, See OSTI ID Number
Object Type: Report
System: The UNT Digital Library
[Funeral Program for Derek Dewayne Dixon, February 23, 2008] (open access)

[Funeral Program for Derek Dewayne Dixon, February 23, 2008]

Funeral program for Derek Dewayne Dixon, born May 16, 1984 and died February 17, 2008. The funeral was held February 23, 2008 at Redeeming Grace Baptist Church, officiated by Pastor Kenneth Brown. Funeral arrangements were made through Lewis Funeral Home and he was buried in Meadowlawn Memorial Park in San Antonio, Texas.
Date: February 23, 2008
Creator: A Clark's Creation
Object Type: Pamphlet
System: The Portal to Texas History
IBS and Expected Luminosity Performance For RHIC Beams At Top Energy With 56 MHz SRF Cavity (open access)

IBS and Expected Luminosity Performance For RHIC Beams At Top Energy With 56 MHz SRF Cavity

N/A
Date: October 1, 2008
Creator: A., Fedotov
Object Type: Report
System: The UNT Digital Library
RHIC Performance with 56 MHz RF and Gold Ion Beams Pre-cooled at Lower Energy (open access)

RHIC Performance with 56 MHz RF and Gold Ion Beams Pre-cooled at Lower Energy

N/A
Date: October 1, 2008
Creator: A., Fedotov
Object Type: Report
System: The UNT Digital Library
Emittance Reduction between EBIS LINAC and Booster by Electron Beam Cooling - Is Single Pass Cooling Possible? (open access)

Emittance Reduction between EBIS LINAC and Booster by Electron Beam Cooling - Is Single Pass Cooling Possible?

N/A
Date: April 1, 2008
Creator: A., Hershcovitch
Object Type: Report
System: The UNT Digital Library
Part II/Addendum Electron Beam Cooling between EBIS LINAC and Booster; Is Single Pass Cooling Possible? (open access)

Part II/Addendum Electron Beam Cooling between EBIS LINAC and Booster; Is Single Pass Cooling Possible?

N/A
Date: July 1, 2008
Creator: A., Hershcovitch
Object Type: Report
System: The UNT Digital Library
Spherical Aberration Corrections for an Electrostatic Gridded Lens (open access)

Spherical Aberration Corrections for an Electrostatic Gridded Lens

N/A
Date: May 1, 2008
Creator: A., Pikin
Object Type: Report
System: The UNT Digital Library
Generalization of the ERIT Principle and Method (open access)

Generalization of the ERIT Principle and Method

N/A
Date: February 1, 2008
Creator: A., Ruggiero
Object Type: Report
System: The UNT Digital Library
Tracking of Acceleration with HNJ Method (open access)

Tracking of Acceleration with HNJ Method

N/A
Date: February 1, 2008
Creator: A., Ruggiero
Object Type: Report
System: The UNT Digital Library
Prediction of atmospheric δ13CO2 using fossil plant tissues. Reviews of Geophysics, 46/2006RG0002.(view/download pdf) (open access)

Prediction of atmospheric δ13CO2 using fossil plant tissues. Reviews of Geophysics, 46/2006RG0002.(view/download pdf)

To summarize the content: we presented the results of laboratory experiments designed to quantify the relationship between plant tissue δ13C and δ13CO2 values under varying environmental conditions, including differential pCO2 ranging from 1 to 3 times today’s levels. As predicted, plants grown under elevated pCO2 showed increased average biomass compared to controls grown at the same temperature. Across a very large range in δ13Ca (≈ 24 ‰) and pCO2 (≈ 740 ppmv) we observed a consistent correlation between δ13Ca and δ13Cp (p<0.001). We show an average isotopic depletion of −25.4 ‰ for above-ground tissue and −23.2 ‰ for below-ground tissue of Raphanus sativus L. relative to the composition of the atmosphere under which it formed. For both above- and below-ground tissue, grown at both ~23 ˚C and ~29 ˚C, correlation was strong and significant (r2 ≥ 0.98, p<0.001); variation in pCO2 level had little or no effect on this relationship.
Date: June 30, 2008
Creator: A.H. Jahren, N.C. Arens and S.A. Harbeson
Object Type: Report
System: The UNT Digital Library
Simulation of Alpha-Channeling in Mirror Machines (open access)

Simulation of Alpha-Channeling in Mirror Machines

Applying α-channeling techniques to mirror machines can significantly increase their effective reactivity, thus making open configurations more advantageous for practical fusion. A large fraction of α particle energy can be extracted using rf waves. Effects employed to cool α particles can also in principle be used to heat the fusion ions; the possibility to design a configuration of rf waves which could be used to perform both tasks is demonstrated.
Date: March 17, 2008
Creator: A.I. Zhmoginov, N.J. Fisch
Object Type: Report
System: The UNT Digital Library
NUCLEAR WASTE GLASSES CONTINUOUS MELTING AND BULK VITRIFICAITON (open access)

NUCLEAR WASTE GLASSES CONTINUOUS MELTING AND BULK VITRIFICAITON

This contribution addresses various aspects of nuclear waste vitrification. Nuclear wastes have a variety of components and composition ranges. For each waste composition, the glass must be formulated to possess acceptable processing and product behavior defined in terms of physical and chemical properties that guarantee the glass can be easily made and resist environmental degradation. Glass formulation is facilitated by developing property-composition models, and the strategy of model development and application is reviewed. However, the large variability of waste compositions presents numerous additional challenges: insoluble solids and molten salts may segregate; foam may hinder heat transfer and slow down the process; molten salts may accumulate in container refractory walls; the glass on cooling may precipitate crystalline phases. These problems need targeted exploratory research. Examples of specific problems and their possible solutions are discussed.
Date: March 24, 2008
Creator: AA, KRUGER & PR, HRMA
Object Type: Article
System: The UNT Digital Library
Alignment validation (open access)

Alignment validation

The four experiments, ALICE, ATLAS, CMS and LHCb are currently under constructionat CERN. They will study the products of proton-proton collisions at the Large Hadron Collider. All experiments are equipped with sophisticated tracking systems, unprecedented in size and complexity. Full exploitation of both the inner detector andthe muon system requires an accurate alignment of all detector elements. Alignmentinformation is deduced from dedicated hardware alignment systems and the reconstruction of charged particles. However, the system is degenerate which means the data is insufficient to constrain all alignment degrees of freedom, so the techniques are prone to converging on wrong geometries. This deficiency necessitates validation and monitoring of the alignment. An exhaustive discussion of means to validate is subject to this document, including examples and plans from all four LHC experiments, as well as other high energy experiments.
Date: September 6, 2008
Creator: ALICE; ATLAS; CMS; LHCb & Golling, Tobias
Object Type: Article
System: The UNT Digital Library
Archaeological Survey of the Proposed Weatherford 12-Inch Sewer Pipeline Route, Parker County, Texas (open access)

Archaeological Survey of the Proposed Weatherford 12-Inch Sewer Pipeline Route, Parker County, Texas

Results of field and archaeological investigations along with recommendations concerning proposed sewer pipeline.
Date: 2008
Creator: AR Consultants
Object Type: Report
System: The Portal to Texas History
DEWATERING TREATMENT SCALE-UP TESTING RESULTS OF HANFORD TANK WASTES (open access)

DEWATERING TREATMENT SCALE-UP TESTING RESULTS OF HANFORD TANK WASTES

This report documents CH2M HILL Hanford Group Inc. (CH2M HILL) 2007 dryer testing results in Richland, WA at the AMEC Nuclear Ltd., GeoMelt Division (AMEC) Horn Rapids Test Site. It provides a discussion of scope and results to qualify the dryer system as a viable unit-operation in the continuing evaluation of the bulk vitrification process. A 10,000 liter (L) dryer/mixer was tested for supplemental treatment of Hanford tank low-activity wastes, drying and mixing a simulated non-radioactive salt solution with glass forming minerals. Testing validated the full scale equipment for producing dried product similar to smaller scale tests, and qualified the dryer system for a subsequent integrated dryer/vitrification test using the same simulant and glass formers. The dryer system is planned for installation at the Hanford tank farms to dry/mix radioactive waste for final treatment evaluation of the supplemental bulk vitrification process.
Date: January 23, 2008
Creator: AR, TEDESCHI