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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
[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
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
Search for the Higgs boson in events with missing transverse energy and b quark jets produced in proton-antiproton collisions at s**(1/2)=1.96 TeV (open access)

Search for the Higgs boson in events with missing transverse energy and b quark jets produced in proton-antiproton collisions at s**(1/2)=1.96 TeV

We search for the standard model Higgs boson produced in association with an electroweak vector boson in events with no identified charged leptons, large imbalance in transverse momentum, and two jets where at least one contains a secondary vertex consistent with the decay of b hadrons. We use {approx}1 fb{sup -1} integrated luminosity of p{bar p} collisions at {radical}s = 1.96 TeV recorded by the CDF II experiment at the Tevatron. We find 268 (16) single (double) b-tagged candidate events, where 248 {+-} 43 (14.4 {+-} 2.7) are expected from standard model background processes. We place 95% confidence level upper limits on the Higgs boson production cross section for several Higgs boson masses ranging from 110 GeV/c{sup 2} to 140 GeV/c{sup 2}. For a mass of 115 GeV/c{sup 2} the observed (expected) limit is 20.4 (14.2) times the standard model prediction.
Date: February 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
Two-Particle Momentum Correlations in Jets Produced in p antip Collisions at s**(1/2) = 1.96-TeV (open access)

Two-Particle Momentum Correlations in Jets Produced in p antip Collisions at s**(1/2) = 1.96-TeV

None
Date: February 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
Study of direct CP violation in B+- ---> J/psi K+- (pi+-) file decays (open access)

Study of direct CP violation in B+- ---> J/psi K+- (pi+-) file decays

The authors present a search for direct CP violation in B{sup {+-}} {yields} J/{psi}K{sup {+-}}{pi}{sup {+-}} decays. The event sample is selected from 2.8 fb{sup -1} of p{bar p} collisions recorded by D0 experiment in Run II of the Fermilab Tevatron Collider. The charge asymmetry A{sub CP}(B{sup +} {yields} J/{psi}K{sup +}) = +0.0075 {+-} 0.0061(stat.) {+-} 0.0027(syst.) is obtained using a sample of approximately 40 thousand B{sup {+-}} {yields} J/{psi}K{sup {+-}} decays. The achieved precision is of the same level as the expected deviation predicted by some extensions of the standard model. They also measured the charge asymmetry A{sub CP}(B{sup +} {yields} J/{psi}{pi}{sup +}) = -0.09 {+-} 0.08(stat.){+-}0.03(syst.).
Date: February 1, 2008
Creator: Abazov, V. M.; /Dubna, JINR; Abbott, B.; U., /Oklahoma; Abolins, M.; U., /Michigan State et al.
Object Type: Article
System: The UNT Digital Library
Measurement of B0(s) mixing parameters from the flavor-tagged decay B0(s) ---> J/psi phi (open access)

Measurement of B0(s) mixing parameters from the flavor-tagged decay B0(s) ---> J/psi phi

From an analysis of the flavor-tagged decay B{sub s}{sup 0} {yields} J/{psi}{phi} they obtain the width difference between the B{sub s}{sup 0} light and heavy mass eigenstates, {Delta}{Lambda}{sub s} {triple_bond} {Lambda}{sub L} - {Lambda}{sub H} = 0.19 {+-} 0.07(stat){sub -0.01}{sup +0.02}(syst) ps{sup -1}, and the CP-violating phase, {phi}{sub s} = -0.57{sub -0.30}{sup +0.24}(stat){sub -0.02}{sup +0.07}(syst). The allowed 90% C.L. intervals of {Delta}{Lambda}{sub s} and {phi}{sub s} are 0.06 < {Delta}{Lambda}{sub s} < 0.30 ps{sup -1} and -1.20 < {phi}{sub s} < 0.06, respectively. The data sample corresponds to an integrated luminosity of 2.8 fb{sup -1} accumulated with the D0 detector at the Fermilab Tevatron collider.
Date: February 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the B(c) meson mass in the exclusive decay B(c) ---> J / psi pi (open access)

Measurement of the B(c) meson mass in the exclusive decay B(c) ---> J / psi pi

None
Date: February 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the inclusive jet cross-section in p anti-p collisions at s**91/2) =1.96-TeV (open access)

Measurement of the inclusive jet cross-section in p anti-p collisions at s**91/2) =1.96-TeV

None
Date: February 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Smart Grid Provisions in H.R. 6, 110th Congress (open access)

Smart Grid Provisions in H.R. 6, 110th Congress

This report provides an overview of Smart Grid, a distribution system that allows for flow of information from a customer's meter in two directions. It discusses both regulatory and technological barriers that have limited the implementation of Smart Grid technology.
Date: February 13, 2008
Creator: Abel, Amy
Object Type: Report
System: The UNT Digital Library
Abilene Philharmonic Playbill: February 23-April 19, 2008 (open access)

Abilene Philharmonic Playbill: February 23-April 19, 2008

Program for an Abilene Philharmonic concert that ran from February 23rd to April 19th during the 58th season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: February 2008
Creator: Abilene Philharmonic
Object Type: Pamphlet
System: The Portal to Texas History
Determination of the Parity of the Neutral Pion via the Four-Electron Decay (open access)

Determination of the Parity of the Neutral Pion via the Four-Electron Decay

We present a new determination of the parity of the neutral pion via the double Dalitz decay {pi}{sup 0} {yields} e{sup +}e{sup -}e{sup +}e{sup -}. Our sample, which consists of 30 511 candidate decays, was collected from K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{pi}{sup 0} decays in flight at the KTeV-E799 experiment at Fermi National Accelerator Laboratory. We confirm the negative {pi}{sup 0} parity, and place a limit on scalar contributions to the {pi}{sup 0} {yields} e{sup +}e{sup -}e{sup +}e{sup -} decay amplitude of less than 3.3% assuming CPT conservation. The {pi}{sup 0}{gamma}*{gamma}* form factor is well described by a momentum-dependent model with a slope parameter fit to the final state phase space distribution. Additionally, we have measured the branching ratio of this mode to be B({pi}{sup 0} {yields} e{sup +}e{sup -}e{sup +}e{sup -}) = (3.26 {+-} 0.18) x 10{sup -5}.
Date: February 1, 2008
Creator: Abouzaid, E.; Arenton, M.; Barker, A. R.; Bellantoni, L.; Blucher, E.; Bock, G. J. et al.
Object Type: Article
System: The UNT Digital Library
Transmission System Performance Analysis for High-Penetration Photovoltaics (open access)

Transmission System Performance Analysis for High-Penetration Photovoltaics

This study is an assessment of the potential impact of high levels of penetration of photovoltaic (PV) generation on transmission systems. The effort used stability simulations of a transmission system with different levels of PV generation and load.
Date: February 1, 2008
Creator: Achilles, S.; Schramm, S. & Bebic, J.
Object Type: Report
System: The UNT Digital Library
Searches for Long-lived Particles at the Tevatron Collider (open access)

Searches for Long-lived Particles at the Tevatron Collider

None
Date: February 1, 2008
Creator: Adams, T.
Object Type: Article
System: The UNT Digital Library
Beam Emittance Measurement with Laser Wire Scanners in the ILC Beam Delivery System (open access)

Beam Emittance Measurement with Laser Wire Scanners in the ILC Beam Delivery System

Accurate measurement of the beam phase-space is essential for the next generation of electron accelerators. A scheme for beam optics optimization and beam matrix reconstruction algorithms for the diagnostics section of the beam delivery system of the International Linear Collider based on laser-wire beam profile monitors are discussed. Possible modes of operation of the laser-wire system together with their corresponding performance are presented. Based on these results, prospects for reconstructing the ILC beam emittance from representative laser-wire beam size measurements are evaluated.
Date: February 1, 2008
Creator: Agapov, I.; Blair, G.A. & Woodley, M.
Object Type: Article
System: The UNT Digital Library
Fluxnet Synthesis Dataset Collaboration Infrastructure (open access)

Fluxnet Synthesis Dataset Collaboration Infrastructure

The Fluxnet synthesis dataset originally compiled for the La Thuile workshop contained approximately 600 site years. Since the workshop, several additional site years have been added and the dataset now contains over 920 site years from over 240 sites. A data refresh update is expected to increase those numbers in the next few months. The ancillary data describing the sites continues to evolve as well. There are on the order of 120 site contacts and 60proposals have been approved to use thedata. These proposals involve around 120 researchers. The size and complexity of the dataset and collaboration has led to a new approach to providing access to the data and collaboration support and the support team attended the workshop and worked closely with the attendees and the Fluxnet project office to define the requirements for the support infrastructure. As a result of this effort, a new website (http://www.fluxdata.org) has been created to provide access to the Fluxnet synthesis dataset. This new web site is based on a scientific data server which enables browsing of the data on-line, data download, and version tracking. We leverage database and data analysis tools such as OLAP data cubes and web reports to enable browser …
Date: February 6, 2008
Creator: Agarwal, Deborah A.; Humphrey, Marty; van Ingen, Catharine; Beekwilder, Norm; Goode, Monte; Jackson, Keith et al.
Object Type: Report
System: The UNT Digital Library
Neutron capture cross sections of 151,153Eu (open access)

Neutron capture cross sections of 151,153Eu

None
Date: February 13, 2008
Creator: Agvaanluvsan, U.; Becker, J. A.; Macri, R. A.; Parker, W. E.; Wilk, P. A.; Wu, C. Y. et al.
Object Type: Report
System: The UNT Digital Library
European Union–U.S. Trade and Investment Relations: Key Issues (open access)

European Union–U.S. Trade and Investment Relations: Key Issues

None
Date: February 14, 2008
Creator: Aheam, Raymond J.; Fischer, John W.; Goldfarb, Charles B.; Hanrahan, Charles E.; Eubanks, Walter W. & Rubin, Janice E.
Object Type: Report
System: The UNT Digital Library
Study of Charmed Baryon Sigma(C)(2800) Production at the BaBar Experiment (open access)

Study of Charmed Baryon Sigma(C)(2800) Production at the BaBar Experiment

This dissertation reports on a study of search for an orbitally excited state of charmed baryons {Sigma}{sub c}{sup 0}(2800) and {Sigma}{sub c}{sup ++}(2800). They measure the widths, momentum spectrum and production cross-section for these states decaying into a {Lambda}{sub c}{sup +} and a charged {pi}. The analysis uses 230 fb{sup -1} of data collected at BABAR detector operating at PEP-II collider at Stanford Linear Accelerator Center. The data is collected in the region of {Upsilon}(4S) an {approx} 40 MeV below the resonance. {Lambda}{sub c}{sup +} baryon is reconstructed in the decay mode pK{sup -}{pi}{sup +}. The {Sigma}{sub c}(2800) baryon production at continuum is observed to be quite significant for x{sub p} > 0.7, where x{sub p} = p/{radical}E{sup 2}+M{sup 2} is the scaled momentum and varies from 0.0 to 1.0. The momentum spectrum is measured by considering the corrected yield for momentum bins above x{sub p} > 0.5 and can be parameterized very well by a Peterson function, given by: dN/dx{sub p} {proportional_to} 1/x{sub p}(1 - 1/x{sub p} - {epsilon}/1-x{sub p}){sup 2}. The values for the peterson parameter {epsilon}, are found to be 0.050 {+-} 0.010 for {Sigma}{sub c}{sup 0}(2800) and 0.057 {+-} 0.012 for {Sigma}{sub c}{sup ++}(2800). They use …
Date: February 29, 2008
Creator: Ahmded, Shamona
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Overcoming Scalability Challenges for Tool Daemon Launching (open access)

Overcoming Scalability Challenges for Tool Daemon Launching

Many tools that target parallel and distributed environments must co-locate a set of daemons with the distributed processes of the target application. However, efficient and portable deployment of these daemons on large scale systems is an unsolved problem. We overcome this gap with LaunchMON, a scalable, robust, portable, secure, and general purpose infrastructure for launching tool daemons. Its API allows tool builders to identify all processes of a target job, launch daemons on the relevant nodes and control daemon interaction. Our results show that Launch-MON scales to very large daemon counts and substantially enhances performance over existing ad hoc mechanisms.
Date: February 15, 2008
Creator: Ahn, D H; Arnold, D C; de Supinski, B R; Lee, G L; Miller, B P & Schulz, M
Object Type: Article
System: The UNT Digital Library
Surface roughness effects on the solar reflectance of cool asphalt shingles (open access)

Surface roughness effects on the solar reflectance of cool asphalt shingles

We analyze the solar reflectance of asphalt roofing shingles that are covered with pigmented mineral roofing granules. The reflecting surface is rough, with a total area approximately twice the nominal area. We introduce a simple analytical model that relates the 'micro-reflectance' of a small surface region to the 'macro-reflectance' of the shingle. This model uses a mean field approximation to account for multiple scattering effects. The model is then used to compute the reflectance of shingles with a mixture of different colored granules, when the reflectances of the corresponding mono-color shingles are known. Simple linear averaging works well, with small corrections to linear averaging derived for highly reflective materials. Reflective base granules and reflective surface coatings aid achievement of high solar reflectance. Other factors that influence the solar reflectance are the size distribution of the granules, coverage of the asphalt substrate, and orientation of the granules as affected by rollers during fabrication.
Date: February 17, 2008
Creator: Akbari, Hashem; Berdahl, Paul; Akbari, Hashem; Jacobs, Jeffry & Klink, Frank
Object Type: Article
System: The UNT Digital Library
Lepton Flavor Violation in Predictive SUSY-GUT Models (open access)

Lepton Flavor Violation in Predictive SUSY-GUT Models

There have been many theoretical models constructed which aim to explain the neutrino masses and mixing patterns. While many of the models will be eliminated once more accurate determinations of the mixing parameters, especially sin{sup 2} 2{theta}{sub 13}, are obtained, charged lepton flavor violation (LFV) experiments are able to differentiate even further among the models. In this paper, they investigate various rare LFV processes, such as {ell}{sub i} {yields} {ell}{sub j} + {gamma} and {mu} - e conversion, in five predictive SUSY SO(10) models and their allowed soft SUSY breaking parameter space in the constrained minimal SUSY standard model (CMSSM). Utilizing the WMAP dark matter constraints, they obtain lower bounds on the branching ratios of these rare processes and find that at least three of the five models they consider give rise to predictions for {mu} {yields} e + {gamma} that will be tested by the MEG collaboration at PSI. in addition, the next generation {mu} - e conversion experiment has sensitivity to the predictions of all five models, making it an even more robust way to test these models. While generic studies have emphasized the dependence of the branching ratios of these rare processes on the reactor neutrino angle, …
Date: February 1, 2008
Creator: Albright, Carl H. & Chen, Mu-Chun
Object Type: Article
System: The UNT Digital Library
Achieve Continuous Injection of Solid Fuels into Advanced Combustion System Pressures (open access)

Achieve Continuous Injection of Solid Fuels into Advanced Combustion System Pressures

This report is a descriptive journey of the Achieve Continuous Injection of Solid Fuels into Advanced Combustion System Pressures.
Date: February 28, 2008
Creator: Aldred, Derek L. & Saunders, Timothy
Object Type: Report
System: The UNT Digital Library