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The 8 O'Clock Arc: A Serendipitous Discovery of a Strongly Lensed Lyman Break Galaxy in the SDSS DR4 Imaging Data (open access)

The 8 O'Clock Arc: A Serendipitous Discovery of a Strongly Lensed Lyman Break Galaxy in the SDSS DR4 Imaging Data

We report on the serendipitous discovery of the brightest Lyman Break Galaxy (LBG) currently known, a galaxy at z = 2.73 that is being strongly lensed by the z = 0.38 Luminous Red Galaxy (LRG) SDSS J002240.91+143110.4. The arc of this gravitational lens system, which we have dubbed the ''8 o'clock arc'' due to its time of discovery, was initially identified in the imaging data of the Sloan Digital Sky Survey Data Release 4 (SDSS DR4); followup observations on the Astrophysical Research Consortium (ARC) 3.5m telescope at Apache Point Observatory confirmed the lensing nature of this system and led to the identification of the arc's spectrum as that of an LBG. The arc has a spectrum and a redshift remarkably similar to those of the previous record-holder for brightest LBG (MS 1512-cB58, a.k.a ''cB58''), but, with an estimated total magnitude of (g,r,i) = (20.0,19.2,19.0) and surface brightness of ({mu}{sub g}, {mu}{sub r}, {mu}{sub i}) = (23.3, 22.5, 22.3) mag arcsec{sup -2}, the 8 o'clock arc is thrice as bright. The 8 o'clock arc, which consists of three lensed images of the LBG, is 162{sup o}(9.6'') long and has a length-to-width ratio of 6:1. A fourth image of the LBG--a counter-image--can …
Date: November 1, 2006
Creator: Allam, Sahar S.; Tucker, Douglas L.; Lin, Huan; Diehl, H. Thomas; Annis, James; Buckley-Geer, Elizabeth J. et al.
Object Type: Article
System: The UNT Digital Library
100,000-Mile Evaluation of Transit Buses Operated on Biodiesel Blends (B20) (open access)

100,000-Mile Evaluation of Transit Buses Operated on Biodiesel Blends (B20)

Evaluates the emissions, fuel economy, and maintenance of five 40-foot transit buses operated on B20 compared to four on petroleum diesel.
Date: November 1, 2006
Creator: Proc, K.; Barnitt, R.; Hayes, R. R.; Ratcliff, M.; McCormick, R. L.; Ha, L. et al.
Object Type: Article
System: The UNT Digital Library
2007 Wholesale Power Rate Schedules : 2007 General Rate Schedule Provisions. (open access)

2007 Wholesale Power Rate Schedules : 2007 General Rate Schedule Provisions.

This schedule is available for the contract purchase of Firm Power to be used within the Pacific Northwest (PNW). Priority Firm (PF) Power may be purchased by public bodies, cooperatives, and Federal agencies for resale to ultimate consumers, for direct consumption, and for Construction, Test and Start-Up, and Station Service. Rates in this schedule are in effect beginning October 1, 2006, and apply to purchases under requirements Firm Power sales contracts for a three-year period. The Slice Product is only available for public bodies and cooperatives who have signed Slice contracts for the FY 2002-2011 period. Utilities participating in the Residential Exchange Program (REP) under Section 5(c) of the Northwest Power Act may purchase Priority Firm Power pursuant to the Residential Exchange Program. Rates under contracts that contain charges that escalate based on BPA's Priority Firm Power rates shall be based on the three-year rates listed in this rate schedule in addition to applicable transmission charges. This rate schedule supersedes the PF-02 rate schedule, which went into effect October 1, 2001. Sales under the PF-07 rate schedule are subject to BPA's 2007 General Rate Schedule Provisions (2007 GRSPs). Products available under this rate schedule are defined in the 2007 GRSPs. …
Date: November 1, 2006
Creator: United States. Bonneville Power Administration.
Object Type: Report
System: The UNT Digital Library
Active resonant subwavelength grating for scannerless range imaging sensors. (open access)

Active resonant subwavelength grating for scannerless range imaging sensors.

In this late-start LDRD, we will present a design for a wavelength-agile, high-speed modulator that enables a long-term vision for the THz Scannerless Range Imaging (SRI) sensor. It takes the place of the currently-utilized SRI micro-channel plate which is limited to photocathode sensitive wavelengths (primarily in the visible and near-IR regimes). Two of Sandia's successful technologies--subwavelength diffractive optics and THz sources and detectors--are poised to extend the capabilities of the SRI sensor. The goal is to drastically broaden the SRI's sensing waveband--all the way to the THz regime--so the sensor can see through image-obscuring, scattering environments like smoke and dust. Surface properties, such as reflectivity, emissivity, and scattering roughness, vary greatly with the illuminating wavelength. Thus, objects that are difficult to image at the SRI sensor's present near-IR wavelengths may be imaged more easily at the considerably longer THz wavelengths (0.1 to 1mm). The proposed component is an active Resonant Subwavelength Grating (RSG). Sandia invested considerable effort on a passive RSG two years ago, which resulted in a highly-efficient (reflectivity greater than gold), wavelength-specific reflector. For this late-start LDRD proposal, we will transform the passive RSG design into an active laser-line reflector.
Date: November 1, 2006
Creator: Kemme, Shanalyn A.; Nellums, Robert O.; Boye, Robert R. & Peters, David William
Object Type: Report
System: The UNT Digital Library
Addressing the workforce pipeline challenge (open access)

Addressing the workforce pipeline challenge

A secure and affordable energy supply is essential for achieving U.S. national security, in continuing U.S. prosperity and in laying the foundations to enable future economic growth. To meet this goal the next generation energy workforce in the U.S., in particular those needed to support instrumentation, controls and advanced operations and maintenance, is a critical element. The workforce is aging and a new workforce pipeline, to support both current generation and new build has yet to be established. The paper reviews the challenges and some actions being taken to address this need.
Date: November 1, 2006
Creator: Bond, Leonard; Kostelnik, Kevin & Holman, Richard
Object Type: Article
System: The UNT Digital Library
Advances in Acid Concentration Membrane Technology for the Sulfur-Iodine Thermochemical Cycle (open access)

Advances in Acid Concentration Membrane Technology for the Sulfur-Iodine Thermochemical Cycle

One of the most promising cycles for the thermochemical generation of hydrogen is the Sulfur-Iodine (S-I) process, where aqueous HI is thermochemically decomposed into H2 and I2 at approximately 350 degrees Celsius. Regeneration of HI is accomplished by the Bunsen reaction (reaction of SO2, water, and iodine to generate H2SO4 and HI). Furthermore, SO2 is regenerated from the decomposition of H2SO4 at 850 degrees Celsius yielding the SO2 as well as O2. Thus, the cycle actually consists of two concurrent oxidation-reduction loops. As HI is regenerated, co-produced H2SO4 must be separated so that each may be decomposed. Current flowsheets employ a large amount (~83 mol% of the entire mixture) of elemental I2 to cause the HI and the H2SO4 to separate into two phases. To aid in the isolation of HI, which is directly decomposed into hydrogen, water and iodine must be removed. Separation of iodine is facilitated by removal of water. Sulfuric acid concentration is also required to facilitate feed recycling to the sulfuric acid decomposer. Decomposition of the sulfuric acid is an equilibrium limited process that leaves a substantial portion of the acid requiring recycle. Distillation of water from sulfuric acid involves significant corrosion issues at the liquid-vapor …
Date: November 1, 2006
Creator: Stewart, Frederick F. & Orme, Christopher J.
Object Type: Article
System: The UNT Digital Library
Alternative Fuels Data Center -- Providing Biofuels Tools and Information (open access)

Alternative Fuels Data Center -- Providing Biofuels Tools and Information

This fact sheet describes the various services and Web sites of the Alternative Fuels Data Center.
Date: November 1, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 108, No. 184, Ed. 1 Wednesday, November 1, 2006 (open access)

Altus Times (Altus, Okla.), Vol. 108, No. 184, Ed. 1 Wednesday, November 1, 2006

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: November 1, 2006
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling. (open access)

Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams …
Date: November 1, 2006
Creator: Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX) et al.
Object Type: Report
System: The UNT Digital Library
Application of a Sweating Manikin Controlled by a Human Physiological Model and Lessons Learned (open access)

Application of a Sweating Manikin Controlled by a Human Physiological Model and Lessons Learned

Discusses two applications of NREL's suite of thermal comfort tools: one to assess impact of an automotive ventilated seat on comfort and fuel economy, and another to evaluate liquid cooling garments for NASA spacesuits.
Date: November 1, 2006
Creator: Rugh, J. & Lustbader, J.
Object Type: Article
System: The UNT Digital Library
Application of a Swelling/Shrinkage Model for Analysis of Reservoir Performance at a Field Site (open access)

Application of a Swelling/Shrinkage Model for Analysis of Reservoir Performance at a Field Site

This report talks about Application of a Swelling/Shrinkage Model for Analysis of Reservoir Performance at a Field Site
Date: November 1, 2006
Creator: Siriwardane, H. & Smith, D. H.
Object Type: Article
System: The UNT Digital Library
ASC Computational Environment (ACE) requirements version 8.0 final report. (open access)

ASC Computational Environment (ACE) requirements version 8.0 final report.

A decision was made early in the Tri-Lab Usage Model process, that the collection of the user requirements be separated from the document describing capabilities of the user environment. The purpose in developing the requirements as a separate document was to allow the requirements to take on a higher-level view of user requirements for ASC platforms in general. In other words, a separate ASC user requirement document could capture requirements in a way that was not focused on ''how'' the requirements would be fulfilled. The intent of doing this was to create a set of user requirements that were not linked to any particular computational platform. The idea was that user requirements would endure from one ASC platform user environment to another. The hope was that capturing the requirements in this way would assist in creating stable user environments even though the particular platforms would be evolving and changing. In order to clearly make the separation, the Tri-lab S&CS program decided to create a new title for the requirements. The user requirements became known as the ASC Computational Environment (ACE) Requirements.
Date: November 1, 2006
Creator: Larzelere, Alex R. (Exagrid Engineering, Alexandria, VA) & Sturtevant, Judith E.
Object Type: Report
System: The UNT Digital Library
Basic Research Needs for Clean and Efficient Combustion of 21st Century Transportation Fuels (open access)

Basic Research Needs for Clean and Efficient Combustion of 21st Century Transportation Fuels

To identify basic research needs and opportunities underlying utilization of evolving transportation fuels, with a focus on new or emerging science challenges that have the potential for significant long-term impact on fuel efficiency and emissions.
Date: November 1, 2006
Creator: McIlroy, A.; McRae, G.; Sick, V.; Siebers, D. L.; Westbrook, C. K.; Smith, P. J. et al.
Object Type: Report
System: The UNT Digital Library
Battery Thermal Management System Design Modeling (open access)

Battery Thermal Management System Design Modeling

Looks at the impact of cooling strategies with air and both direct and indirect liquid cooling for battery thermal management.
Date: November 1, 2006
Creator: Pesaran, A. & Kim, G. H.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 85, No. 341, Ed. 1 Wednesday, November 1, 2006 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 85, No. 341, Ed. 1 Wednesday, November 1, 2006

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 1, 2006
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Beam diagnostics, collimation, injection/extraction, targetry, accidents and commissioning: Working group C&G summary report (open access)

Beam diagnostics, collimation, injection/extraction, targetry, accidents and commissioning: Working group C&G summary report

The performance of accelerators with high beam power or high stored beam energy is strongly dependent on the way the beam is handled, how beam parameters are measured and how the machine is commissioned. Two corresponding working groups have been organized for the Workshop: group C ''Beam diagnostics, collimation, injection/extraction and targetry'' and group G ''Commissioning strategies and procedures''. It has been realized that the issues to be discussed in these groups are interlaced with the participants involved and interested in the above topics, with an extremely important subject of beam-induced accidents as additional topic. Therefore, we have decided to combine the group sessions as well as this summary report. Status, performance and outstanding issues of each the topic are described in the sections below, with additional observations and proposals by the joint group at the end.
Date: November 1, 2006
Creator: Mokhov, N. V.; Hasegawa, K.; Henderson, S.; Schmidt, R.; Tomizawa, M. & Wittenburg, K.
Object Type: Article
System: The UNT Digital Library
Beam-induced damage to the Tevatron components and what has been done about it (open access)

Beam-induced damage to the Tevatron components and what has been done about it

A beam-induced damage to the Tevatron collimators happened in December 2003 was induced by a failure in the CDF Roman Pot detector positioning during the collider run. Possible scenarios of this failure resulted in an excessive halo generation and superconducting magnet quench have been studied via realistic simulations using the STRUCT and MARS14 codes. It is shown that the interaction of a misbehaved proton beam with the collimators result in a rapid local heating and a possible damage. A detailed consideration is given to the ablation process for the collimator material taking place in high vacuum. It is shown that ablation of tungsten (primary collimator) and stainless steel (secondary collimator) jaws results in creation of a groove in the jaw surface as was observed after the December's accident. The actions undertaken to avoid such an accident in future are described in detail.
Date: November 1, 2006
Creator: Mokhov, N. V.; Czarapata, P. C.; Drozhdin, A. I.; Still, D. A.; /Fermilab; Samulyak, R. V. et al.
Object Type: Article
System: The UNT Digital Library
Bioagent detection using miniaturized NMR and nanoparticle amplification : final LDRD report. (open access)

Bioagent detection using miniaturized NMR and nanoparticle amplification : final LDRD report.

This LDRD program was directed towards the development of a portable micro-nuclear magnetic resonance ({micro}-NMR) spectrometer for the detection of bioagents via induced amplification of solvent relaxation based on superparamagnetic nanoparticles. The first component of this research was the fabrication and testing of two different micro-coil ({micro}-coil) platforms: namely a planar spiral NMR {micro}-coil and a cylindrical solenoid NMR {micro}-coil. These fabrication techniques are described along with the testing of the NMR performance for the individual coils. The NMR relaxivity for a series of water soluble FeMn oxide nanoparticles was also determined to explore the influence of the nanoparticle size on the observed NMR relaxation properties. In addition, The use of commercially produced superparamagnetic iron oxide nanoparticles (SPIONs) for amplification via NMR based relaxation mechanisms was also demonstrated, with the lower detection limit in number of SPIONs per nanoliter (nL) being determined.
Date: November 1, 2006
Creator: Clewett, C. F. M.; Adams, David Price; Fan, Hongyou; Williams, John D.; Sillerud, Laurel O.; Alam, Todd Michael et al.
Object Type: Report
System: The UNT Digital Library
Biodiesel and Other Renewable Diesel Fuels (open access)

Biodiesel and Other Renewable Diesel Fuels

Present federal tax incentives apply to certain types of biomass-derived diesel fuels, which in energy policy and tax laws are described either as renewable diesel or biodiesel. To understand the distinctions between these diesel types it is necessary to understand the technologies used to produce them and the properties of the resulting products. This fact sheet contains definitions of renewable and biodiesel and discusses the processes used to convert biomass to diesel fuel and the properties of biodiesel and renewable diesel fuels.
Date: November 1, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Biological detection and tagging using tailorable, reactive, highly fluorescent chemosensors. (open access)

Biological detection and tagging using tailorable, reactive, highly fluorescent chemosensors.

This program was focused on the development of a fluorogenic chemosensor family that could tuned for reaction with electrophilic (e.g. chemical species, toxins) and nucleophilic (e.g. proteins and other biological molecules) species. Our chemosensor approach utilized the fluorescent properties of well-known berberine-type alkaloids. In situ chemosensor reaction with a target species transformed two out-of-plane, weakly conjugated, short-wavelength chromophores into one rigid, planar, conjugated, chromophore with strong long wavelength fluorescence (530-560 nm,) and large Stokes shift (100-180 nm). The chemosensor was activated with an isourea group which allowed for reaction with carboxylic acid moieties found in amino acids.
Date: November 1, 2006
Creator: Shepodd, Timothy J.; Zifer, Thomas; McElhanon, James Ross & Rahn, Larry A.
Object Type: Report
System: The UNT Digital Library
Burbank Transportation Management Organization: Impact Analysis (open access)

Burbank Transportation Management Organization: Impact Analysis

The Burbank Transportation Management Organization (BTMO), a private, membership-based, nonprofit organization dedicated to traffic reduction and air quality improvement, contracted with the National Renewable Energy Laboratory (NREL), a U.S. Department of Energy-owned, contractor-operated national laboratory, to analyze its member programs and their benefits and effects. This report uses trip data collected by the BTMO, and defines and implements a methodology for quantifying non-traffic benefits such as gasoline savings, productivity, and pollution reduction.
Date: November 1, 2006
Creator: Brown, E. & Aabakken, J.
Object Type: Report
System: The UNT Digital Library
Can Astrophysical Gamma Ray Sources Mimic Dark Matter Annihilation in Galactic Satellites? (open access)

Can Astrophysical Gamma Ray Sources Mimic Dark Matter Annihilation in Galactic Satellites?

The nature of the cosmic dark matter is unknown. The most compelling hypothesis is that dark matter consists of weakly interacting massive particles (WIMPs) in the 100 GeV mass range. Such particles would annihilate in the galactic halo, producing high-energy gamma rays which might be detectable in gamma ray telescopes such as the GLAST satellite. We investigate the ability of GLAST to distinguish between the WIMP annihilation spectrum and the spectrum of known astrophysical source classes. Focusing on the emission from the galactic satellite halos predicted by the cold dark matter model, we find that the WIMP gamma-ray spectrum is unique; the separation from known source classes can be done in a convincing way. We discuss the follow-up of possible WIMP sources with Imaging Atmospheric Cerenkov Telescopes. Finally we discuss the impact that Large Hadron Collider data might have on the study of galactic dark matter.
Date: November 1, 2006
Creator: Baltz, Edward A.; /KIPAC, Menlo Park; Taylor, James E.; U., /Waterloo; Wai, Lawrence L. & /KIPAC, Menlo Park
Object Type: Article
System: The UNT Digital Library
CAPE-OPEN Integration for Advanced Process Engineering Co-Simulation (open access)

CAPE-OPEN Integration for Advanced Process Engineering Co-Simulation

This paper highlights the use of the CAPE-OPEN (CO) standard interfaces in the Advanced Process Engineering Co-Simulator (APECS) developed at the National Energy Technology Laboratory (NETL). The APECS system uses the CO unit operation, thermodynamic, and reaction interfaces to provide its plug-and-play co-simulation capabilities, including the integration of process simulation with computational fluid dynamics (CFD) simulation. APECS also relies heavily on the use of a CO COM/CORBA bridge for running process/CFD co-simulations on multiple operating systems. For process optimization in the face of multiple and some time conflicting objectives, APECS offers stochastic modeling and multi-objective optimization capabilities developed to comply with the CO software standard. At NETL, system analysts are applying APECS to a wide variety of advanced power generation systems, ranging from small fuel cell systems to commercial-scale power plants including the coal-fired, gasification-based FutureGen power and hydrogen production plant.
Date: November 1, 2006
Creator: Zitney, S. E.
Object Type: Article
System: The UNT Digital Library
CDF Run II Monte-Carlo tunes (open access)

CDF Run II Monte-Carlo tunes

Several CDF Run 2 PYTHIA 6.2 tunes (with multiple parton interactions) are presented and compared with HERWIG (without multiple parton interactions) and with the ATLAS PYTHIA tune (with multiple parton interactions). Predictions are made for the ''underlying event'' in high p{sub T} jet production and in Drell-Yan lepton-pair production at the Tevatron and the LHC.
Date: November 1, 2006
Creator: Field, Rick
Object Type: Article
System: The UNT Digital Library