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Measurement of the CKM Angle Gamma in B0 to Anti-D0 (D0) K*0 With a Dalitz Analysis of D0 to K(S) Pi+ Pi- (open access)

Measurement of the CKM Angle Gamma in B0 to Anti-D0 (D0) K*0 With a Dalitz Analysis of D0 to K(S) Pi+ Pi-

The authors present a measurement of the angle {gamma} of the Unitarity Triangle with a Dalitz analysis of neutral D decays to K{sub S}{pi}{sup +}{pi}{sup -} from the processes B{sup 0} {yields} {bar D}{sup 0}(D{sup 0})K*{sup 0} ({bar B}{sup 0} {yields} D{sup 0}({bar D}{sup 0}){bar K}*{sup 0}) with K*{sup 0} {yields} K{sup +}{pi}{sup -} ({bar K}*{sup 0} {yields} K{sup -} {pi}{sup +}). Using a sample of 371 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at PEP II, they measure the angle {gamma} as a function of r{sub S}, the magnitude of the average ratio between b {yields} u and b {yields} c amplitudes. Combining this result with the available information on r{sub S}, they obtain {gamma} = (162 {+-} 56){sup o} or (342 {+-} 56){sup o} and r{sub S} < 0.55 at 95% probability.
Date: June 9, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library
Improved Recovery Boiler Performance Through Control of Combustion, Sulfur, and Alkali Chemistry (open access)

Improved Recovery Boiler Performance Through Control of Combustion, Sulfur, and Alkali Chemistry

This project involved the following objectives: 1. Determine black liquor drying and devolatilization elemental and total mass release rates and yields. 2. Develop a public domain physical/chemical kinetic model of black liquor drop combustion, including new information on drying and devolatilization. 3. Determine mechanisms and rates of sulfur scavenging in recover boilers. 4. Develop non-ideal, public-domain thermochemistry models for alkali salts appropriate for recovery boilers 5. Develop data and a one-dimensional model of a char bed in a recovery boiler. 6. Implement all of the above in comprehensive combustion code and validate effects on boiler performance. 7. Perform gasification modeling in support of INEL and commercial customers. The major accomplishments of this project corresponding to these objectives are as follows: 1. Original data for black liquor and biomass data demonstrate dependencies of particle reactions on particle size, liquor type, gas temperature, and gas composition. A comprehensive particle submodel and corresponding data developed during this project predicts particle drying (including both free and chemisorbed moisture), devolatilization, heterogeneous char oxidation, char-smelt reactions, and smelt oxidation. Data and model predictions agree, without adjustment of parameters, within their respective errors. The work performed under these tasks substantially exceeded the original objectives. 2. A separate …
Date: June 9, 2008
Creator: Baxter, Larry L.
Object Type: Report
System: The UNT Digital Library
TRACE ELEMENT ANALYSES OF URANIUM MATERIALS (open access)

TRACE ELEMENT ANALYSES OF URANIUM MATERIALS

The Savannah River National Laboratory (SRNL) has developed an analytical method to measure many trace elements in a variety of uranium materials at the high part-per-billion (ppb) to low part-per-million (ppm) levels using matrix removal and analysis by quadrapole ICP-MS. Over 35 elements were measured in uranium oxides, acetate, ore and metal. Replicate analyses of samples did provide precise results however none of the materials was certified for trace element content thus no measure of the accuracy could be made. The DOE New Brunswick Laboratory (NBL) does provide a Certified Reference Material (CRM) that has provisional values for a series of trace elements. The NBL CRM were purchased and analyzed to determine the accuracy of the method for the analysis of trace elements in uranium oxide. These results are presented and discussed in the following paper.
Date: June 9, 2008
Creator: Beals, D & Charles Shick, C
Object Type: Article
System: The UNT Digital Library
Complete fabrication of target experimental chamber and implement initial target diagnostics to be used for the first target experiments in NDCX-1 (open access)

Complete fabrication of target experimental chamber and implement initial target diagnostics to be used for the first target experiments in NDCX-1

The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) has completed the fabrication of a new experimental target chamber facility for future Warm Dense Matter (WDM) experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. This achievement provides to the HIFS-VNL unique and state-of-the-art experimental capabilities in preparation for the planned target heating experiments using intense heavy ion beams.
Date: June 9, 2008
Creator: Bieniosek, F.M.; Bieniosek, F.M.; Dickinson, M.R.; Henestroza, E.; Katayanagi, T.; Jung, J.Y. et al.
Object Type: Report
System: The UNT Digital Library
Power System Modeling of 20percent Wind-Generated Electricity by 2030 (open access)

Power System Modeling of 20percent Wind-Generated Electricity by 2030

The Wind Energy Deployment System model was used to estimate the costs and benefits associated with producing 20% of the nation's electricity from wind technology by 2030. This generation capacity expansion model selects from electricity generation technologies that include pulverized coal plants, combined cycle natural gas plants, combustion turbine natural gas plants, nuclear plants, and wind technology to meet projected demand in future years. Technology cost and performance projections, as well as transmission operation and expansion costs, are assumed. This study demonstrates that producing 20% of the nation's projected electricity demand in 2030 from wind technology is technically feasible, not cost-prohibitive, and provides benefits in the forms of carbon emission reductions, natural gas price reductions, and water savings.
Date: June 9, 2008
Creator: Bolinger, Mark A.; Hand, Maureen; Blair, Nate; Wiser, Ryan; Hern, Tracy; Miller, Bart et al.
Object Type: Article
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 109, No. 319, Ed. 1 Monday, June 9, 2008 (open access)

The Altus Times (Altus, Okla.), Vol. 109, No. 319, Ed. 1 Monday, June 9, 2008

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: June 9, 2008
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Mass changes in NSTX Surface Layers with Li Conditioning as Measured by Quartz Microbalances (open access)

Mass changes in NSTX Surface Layers with Li Conditioning as Measured by Quartz Microbalances

Dynamic retention, lithium deposition, and the stability of thick deposited layers were measured by three quartz crystal microbalances (QMB) deployed in plasma shadowed areas at the upper and lower divertor and outboard midplane in the National Spherical Torus Experiment (NSTX). Deposition of 185 {micro}/g/cm{sup 2} over 3 months in 2007 was measured by a QMB at the lower divertor while a QMB on the upper divertor, that was shadowed from the evaporator, received an order of magnitude less deposition. During helium glow discharge conditioning both neutral gas collisions and the ionization and subsequent drift of Li{sup +} interrupted the lithium deposition on the lower divertor. We present calculations of the relevant mean free paths. Occasionally strong variations in the QMB frequency were observed of thick lithium films suggesting relaxation of mechanical stress and/or flaking or peeling of the deposited layers.
Date: June 9, 2008
Creator: C.H. Skinner, H.W. Kugel, A. L. Roquemore, PS. Krstic and A. Beste
Object Type: Article
System: The UNT Digital Library
SYNTHESIS OF THE FULLY PROTECTED PHOSPHORAMIDITE OF THE BENZENE-DNA ADDUCT, N2- (4-HYDROXYPHENYL)-2'-DEOXYGUANOSINE AND INCORPORATION OF THE LATER INTO DNA OLIGOMERS (open access)

SYNTHESIS OF THE FULLY PROTECTED PHOSPHORAMIDITE OF THE BENZENE-DNA ADDUCT, N2- (4-HYDROXYPHENYL)-2'-DEOXYGUANOSINE AND INCORPORATION OF THE LATER INTO DNA OLIGOMERS

N2-(4-Hydroxyphenyl)-2'-deoxyguanosine-5'-O-DMT-3'-phosphoramidite has been synthesized and used to incorporate the N2-(4-hydroxyphenyl)-2'-dG (N2-4-HOPh-dG) into DNA, using solid-state synthesis technology. The key step to obtaining the xenonucleoside is a palladium (Xantphos-chelated) catalyzed N2-arylation (Buchwald-Hartwig reaction) of a fully protected 2'-deoxyguanosine derivative by 4-isobutyryloxybromobenzene. The reaction proceeded in good yield and the adduct was converted to the required 5'-O-DMT-3'-O-phosphoramidite by standard methods. The latter was used to synthesize oligodeoxynucleotides in which the N2-4-HOPh-dG adduct was incorporated site-specifically. The oligomers were purified by reverse-phase HPLC. Enzymatic hydrolysis and HPLC analysis confirmed the presence of this adduct in the oligomers.
Date: June 9, 2008
Creator: Chenna, Ahmed; Gupta, Ramesh C.; Bonala, Radha R.; Johnson, Francis & Huang, Bo
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 88, No. 160, Ed. 1 Monday, June 9, 2008 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 88, No. 160, Ed. 1 Monday, June 9, 2008

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: June 9, 2008
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Electrostatic Dust Detector with Improved Sensitivity (open access)

Electrostatic Dust Detector with Improved Sensitivity

Methods to measure the inventory of dust particles and to remove dust if it approaches safety limits will be required in next-step tokamaks such as ITER. An electrostatic dust detector, based on a fine grid of interlocking circuit traces, biased to 30 or 50 V, has been developed for the detection of dust on remote surfaces in air and vacuum environments. Gaining operational experience of dust detection on surfaces in tokamaks is important, however the level of dust generated in contemporary short-pulse tokamaks is comparatively low and high sensitivity is necessary to measure dust on a shot-by-shot basis. We report on modifications in the detection electronics that have increased the sensitivity of the electrostatic dust detector by a factor of up to 120, - a level suitable for measurements on contemporary tokamaks.
Date: June 9, 2008
Creator: D.P. Boyle, C.H. Skinner, and A. L. Roquemore
Object Type: Report
System: The UNT Digital Library
Characterization of Laccase-like Multicopper Oxidases (LMCOs) in Arabidopsis thaliana (open access)

Characterization of Laccase-like Multicopper Oxidases (LMCOs) in Arabidopsis thaliana

Laccase-like multicopper oxidases (LMCOs) have repeatedly been associated with the process of lignification in plants, and previous work suggested that these enzymes might be acting as specific marker for highly localized, small-scale lignification events in tissues not typically thought of as lignified. However, plant LMCOs typically occur as members of gene families and different family members can display disparate enzyme activities and overlapping patterns of expression in bulk tissues. This study used reporter genes and knockout mutants to document the involvement of a specific Arabidopsis thaliana LMCO family member (At2g30210 ) in early root development, specifically with development of endodermal tissues. Expression of the gene product was found to be under the control of sucrose levels, but the gene also responded to fluctuations in salt concentrations. The expression patterns of this gene were consistent with its involvement in the formation of suberin in the Casparian strip of root endodermis. An additional LMCO (At5g58910) displayed a more generalized expression in the radicles emergent seedlings. Additional members of the Arabidopsis LMCO family (At2g29130, At5g01190, and At5g05390) were also investigated with reporter gene constructs and knockout mutants. Expression of these LMCOs was associated with lignifying xylem, and the genes had over-lapping expression. Single …
Date: June 9, 2008
Creator: Dean, Jeffrey F.D.
Object Type: Report
System: The UNT Digital Library
Mode Conversion of Langmuir to Electromagnetic Waves with Parallel Inhomogeneity in the Solar Wind and the Corona (open access)

Mode Conversion of Langmuir to Electromagnetic Waves with Parallel Inhomogeneity in the Solar Wind and the Corona

Linear mode conversion of Langmuir waves to radiation near the plasma frequency at density gradients is potentially relevant to multiple solar radio emissions, ionospheric radar experiments, laboratory plasma devices, and pulsars. Here we study mode conversion in warm magnetized plasmas using a numerical electron fluid simulation code with the density gradient parallel to the ambient magnetic field B0 for a range of incident Langmuir wavevectors. Our results include: (1) Both o- and x-mode waves are produced for Ω ∝ (ωL)1/3(ωc/ω) somewhat less than 1, contrary to previous ideas. Only o mode is produced for Ω and somewhat greater than 1.5. Here ωc is the (angular) electron cyclotron frequency, ω the angular wave frequency, and L the length scale of the (linear) density gradient. (2) In the unmagnetized limit, equal amounts of o- and x-mode radiation are produced. (3) The mode conversion window narrows as Ω increases. (4) As Ω increases the total electromagnetic field changes from linear to circular polarization, with the o- and x- mode signals remaining circularly polarized. (5) The conversion efficiency to the x mode decreases monotonically as Ω increases while the o-mode conversion efficiency oscillates due to an interference phenomenon between incoming and reflected Langmuir/z modes. …
Date: June 9, 2008
Creator: Eun-Hwa Kim, Iver H. Cairns, and Peter A. Robinson
Object Type: Report
System: The UNT Digital Library
Progress on electron cloud effects calculations for the FNAL main injector (open access)

Progress on electron cloud effects calculations for the FNAL main injector

We have studied the response of the beam to an electron cloud for the Fermilab Main Injector using the Quasistatic Model [1] implemented into the particle-in-cell code Warp [2]. Specifically, we have addressed the effects due to varying the beam intensity, electron cloud density and chromaticity. In addition, we have estimated the contribution to emittance evolution due to beam space-charge effects. We have carried out a comparison between how the beam responds at injection energy and at top energy. We also present some results on the validation of the computational model, and report on progress towards improving the computational model.
Date: June 9, 2008
Creator: Furman, Miguel A; Sonnad, Kiran G.; Furman, Miguel A. & Vay, Jean-Luc
Object Type: Report
System: The UNT Digital Library
Pay for Performance: Linking Employee Pay to Performance Appraisal (open access)

Pay for Performance: Linking Employee Pay to Performance Appraisal

This report discusses issues related to measuring performance across the federal government, and analyzes a variety of methods utilized by the government to measure employee performance and its linkage to pay.
Date: June 9, 2008
Creator: Ginsberg, Wendy
Object Type: Report
System: The UNT Digital Library
CFTC Reauthorization (open access)

CFTC Reauthorization

This report provides brief summaries of current reauthorization issues.
Date: June 9, 2008
Creator: Jickling, Mark
Object Type: Report
System: The UNT Digital Library
Regulation of Energy Derivatives (open access)

Regulation of Energy Derivatives

This report analyzes the development of energy derivatives regulation and proposed legislation.
Date: June 9, 2008
Creator: Jickling, Mark
Object Type: Report
System: The UNT Digital Library
New Results on Leptonic B Meson Decays at BaBar (open access)

New Results on Leptonic B Meson Decays at BaBar

The authors present selected new results on leptonic B meson decays from the BABAR experiment: searches for the decays B{sup 0} {yields} {ell}{sup +}{ell}{sup -}, B{sup +} {yields} {ell}{sup +}{nu} and B{sup 0} {yields} {ell}{sup +}{tau}{sup -}, and B {yields} K{nu}{bar {nu}}, where {ell} = e or {mu}. They observe no evidence for these decays and set upper limits on their branching fractions.
Date: June 9, 2008
Creator: Kim, Hojeong
Object Type: Article
System: The UNT Digital Library
FLUID TRANSIENTS IN A PIPELINE WITH ONE END OPEN (open access)

FLUID TRANSIENTS IN A PIPELINE WITH ONE END OPEN

Water hammer during multi-phase flow is rather complex, but in some cases an upper limit to the pressure surge magnitude during water hammer can be estimated. In the case considered here, a two mile long pipeline with a single high point was permitted to partially drain. Due to gravitational effects, air bubbles up through the pipe line to its highest point, but the time required for air to reach the top of the pipe is rather long. Consequently, some transients caused by valve operations are affected by air entrapment and some are not. The intent of this research was to investigate the complex interactions between air, water vapor, and liquid during water hammer in a long pipe with one end of the pipe open to atmospheric conditions. To understand the system dynamics, experimental data was obtained from a long pipeline with an open end and also from a short, transparent tube. Transient calculations were performed for valve closures and pump operations as applicable. The limitations of available calculation techniques were considered in detail.
Date: June 9, 2008
Creator: Leishear, R
Object Type: Article
System: The UNT Digital Library
Use of Yb(III) Centered Near Infra-Red (NIR) Luminescence to Determine the Hydration State of a 3,2-HOPO based MRI-Contrast Agent (open access)

Use of Yb(III) Centered Near Infra-Red (NIR) Luminescence to Determine the Hydration State of a 3,2-HOPO based MRI-Contrast Agent

It has been more than a decade since the first reports of [Gd(Tren-Me-3,2-HOPO)(H{sub 2}O){sub 2}] as a potential new class of magnetic resonance imaging contrast agent (MRI-CA). The defining feature of these 1-methyl-3-hydroxypyridin-2-one (Me-3,2-HOPO) based compounds has been the use of a hexadentate ligand design, and hence an increase in the number of metal bound water molecules, without sacrificing complex stability compared to the typically octadentate contrast agents used commercially. Since that time, significant advances in the properties of these chelates have been steadily reported, including improvements in relaxivity, incorporation into macromolecular architectures and, recently, the first direct verification of solution structure using the discovery of Eu(III) centered luminescence with the isomeric 1-hydroxypyridin-2-one (1,2-HOPO) chelate as a sensitizing chromophore. Nonetheless, it has remained frustrating that direct measurements of the inner sphere hydration state, q, using luminescence techniques with the parent Me-3,2-HOPO compounds have remained elusive, even when direct laser excitation of weakly absorbing f-f transitions were employed (eg. for Eu(III) complexes). This failing can likely be traced to the presence of a low lying LMCT state which efficiently quenches metal based emission. Instead, estimates of the q and hence solution structure have relied on the fitting of relaxivity data to …
Date: June 9, 2008
Creator: Moore, Evan G.; Seitz, Michael & Raymond, Kenneth N.
Object Type: Article
System: The UNT Digital Library
U.S.-Russian Civilian Nuclear Cooperation Agreement: Issues for Congress (open access)

U.S.-Russian Civilian Nuclear Cooperation Agreement: Issues for Congress

The United States and Russia signed a civilian nuclear cooperation agreement on May 6, 2008. President Bush submitted the agreement to Congress on May 13. This report discusses key policy issues related to that agreement, including future nuclear energy cooperation with Russia, U.S.-Russian bilateral relations, nonproliferation cooperation and Russia's policies toward Iran. This report will be updated.
Date: June 9, 2008
Creator: Nikitin, Mary Beth
Object Type: Report
System: The UNT Digital Library
The US Support program to IAEA Safeguards - 2008 (open access)

The US Support program to IAEA Safeguards - 2008

The U.S. Support Program to IAEA Safeguards (USSP) was established in 1977 to provide technical assistance to the IAEA Department of Safeguards. Since that time the U.S. Department of State has provided funding of over $200 million and over 900 tasks have been completed by USSP contractors on behalf of the KEA. The USSP is directed by a U.S. interagency subcommittee known as the Subgroup on Safeguards Technical Support (SSTS) and is managed by the International Safeguards Project Office (ISPO) at Brookhaven National Laboratory. In recent years, the SSTS and ISPO have identified priorities to guide the process of determining which IAEA requests are aligned with US. policy and will be funded. The USSP priorities are reviewed and updated prior to the USSP Annual Review Meeting which is hosted by the International Atomic Energy Agency (IAEA) each spring in Vienna, Austria. This paper will report on the 2008 USSP priorities and be an introduction for a session which will consist of four papers on USSP priorities and four other papers related to USSP activities.
Date: June 9, 2008
Creator: Pepper,S.
Object Type: Article
System: The UNT Digital Library
South Africa: Current Issues and U.S. Relations (open access)

South Africa: Current Issues and U.S. Relations

This report looks at the relationship between the United States and South Africa. Topics include: foreign policy issues; health (in particular HIV/AIDS) reform; economics and electricity shortages; and corruption in South African politics.
Date: June 9, 2008
Creator: Ploch, Lauren
Object Type: Report
System: The UNT Digital Library
The Federal Food Safety System: A Primer (open access)

The Federal Food Safety System: A Primer

None
Date: June 9, 2008
Creator: Porter, Donna V. & Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
[The Last Word] (open access)

[The Last Word]

Article titled, "The Last Word" from Newsweek. The article is addressing a California Supreme Court ruling that legalizes gay marriage.
Date: June 9, 2008
Creator: Quindlan, Anna
Object Type: Article
System: The UNT Digital Library