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N >= 4 Supergravity Amplitudes from Gauge Theory at Two Loops

Description: We present the full two-loop four-graviton amplitudes in N = 4, 5, 6 supergravity. These results were obtained using the double-copy structure of gravity, which follows from the recently conjectured color-kinematics duality in gauge theory. The two-loop four-gluon scattering amplitudes in N = 0, 1, 2 supersymmetric gauge theory are a second essential ingredient. The gravity amplitudes have the expected infrared behavior: the two-loop divergences are given in terms of the squares of the corresponding one-loop amplitudes. The finite remainders are presented in a compact form. The finite remainder for N = 8 supergravity is also presented, in a form that utilizes a pure function with a very simple symbol.
Date: February 15, 2012
Creator: Boucher-Veronneau, C. & Dixon, L. J.
Partner: UNT Libraries Government Documents Department

5-cm, no iron SSC 6-m dipole test program

Description: Magnet Design B for the Superconducting Super Collider (SSC) consists of a 5 cm diameter collared coil assembly 12 m long with concentric aluminum thermal shields at 10 K and 80 K, a G-10 post type support system and a minimal iron vacuum vessel located at a large radius from the coil. In order to determine the behavior of such a magnet under both direct current and quenching conditions, a 6 m model was built using Tevatron tooling to produce a 7.6 cm diameter coil. The dc operation demonstrated that the post type suspension has acceptable rigidity. Distortions in the aluminum thermal shield during quench resulted from stresses in the material below the yield values. Temperature increases in the thermal shield due to eddy currents were larger than those calculated using simple assumptions, demonstrating the value of using a model to verify eddy current behavior in complex situations.
Date: February 1, 1986
Creator: Mazur, P.O.; Carson, J.A.; Engler, N.H.; Fisk, H.E.; Gonczy, J.D.; Hanft, R.W. et al.
Partner: UNT Libraries Government Documents Department

(6)Li, (7)Li Nuclear Magnetic Resonance Investigation of Lithium Coordination in Binary Phosphate Glasses

Description: {sup 6}Li and {sup 7}Li solid state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy has been used to investigate the local coordination environment of lithium in a series of xLi{sub 2}O {center_dot} (1-x)P{sub 2}O{sub 5} glasses, where 0.05 {le} x {le} 0.55. Both the {sup 6}Li and {sup 7}Li show chemical shift variations with changes in the Li{sub 2}O concentration, but the observed {sup 6}Li NMR chemical shifts closely approximate the true isotropic chemical shift and can provide a measure of the lithium bonding environment. The {sup 6}Li NMR results indicate that in this series of lithium phosphate glasses the Li atoms have an average coordination between four and five. The results for the metaphosphate glass agree with the coordination number and range of chemical shifts observed for crystalline LiPO{sub 3}. An increase in the {sup 6}Li NMR chemical shift with increasing Li{sub 2}O content was observed for the entire concentration range investigated, correlating with increased cross-linking of the phosphate tetrahedral network by O-Li-O bridges. The {sup 6}Li chemical shifts were also observed to vary monotonically through the anomalous glass transition temperature (T{sub g}) minimum. This continuous chemical shift variation shows that abrupt changes in the Li coordination environment do not occur as the Li{sub 2}O concentration is increased, and such abrupt changes can not be used to explain the T{sub g} minimum.
Date: February 8, 1999
Creator: Alam, T.M.; Boyle, T.J.; Brow, R.K. & Conzone, S.
Partner: UNT Libraries Government Documents Department

8 GeV beam line optics optimization for the rapid antiproton transfers at Fermilab

Description: Tevatron Run-II upgrade requires a significant increase of the efficiency and speed of the antiproton transfers from the Accumulator to the Recycler. The goal for the total transfer time is challenging a reduction from 1 hour down to a few minutes. Here we discuss the beam line optics aspects of this project. Results of lattice measurements and optimization are analyzed in terms of transport efficiency and stability.
Date: February 1, 2007
Creator: Nagaslaev, V.; Lebedev, V.; Morgan, J.; Vander Meulen, D. & /Fermilab
Partner: UNT Libraries Government Documents Department

A 10,000 groove/mm multilayer coated grating for EUV spectroscopy

Description: Ultra-high spectral resolution in the EUV and soft x-ray energy ranges requires the use of very high line density gratings with optimal design resulting in use of a Blazed Multilayer Grating (BMG) structure. Here we demonstrate the production of near-atomically perfect Si blazed substrates with an ultra-high groove density (10,000 l/mm) together with the measured and theoretical performance of an Al/Zr multilayer coating on the grating. A 1st order absolute efficiency of 13percent and 24.6percent was achieved at incidence angles of 11o and 36o respectively. Cross-sectional TEM shows the effect of smoothing caused by the surface mobility of deposited atoms and we correlate this effect with a reduction in peak diffraction efficiency. This work shows the high performance that can be achieved with BMGs based on small-period anisotropic etched Si substrates, but also the constraints imposed by the surface mobility of deposited species.
Date: February 7, 2011
Creator: Voronov, Dmytro; Anderson, Erik; Cambie, Rossana; Cabrini, Stefano; Dhuey, Scott; Goray, Leonid et al.
Partner: UNT Libraries Government Documents Department

THE 10,000 YEAR PLAN

Description: Pharkya, a Ph.D. candidate in materials science and engineering, works in the area of corrosion science, predicting how materials will perform over extended periods of time. Her particular focus is a nickel-chromium-molybdenum alloy called C-22, a highly corrosion-resistant metal. Pharkya's aim is to help determine whether containers made from C-22 can be used to store high-energy nuclear waste--for 10,000 years and longer. Pharkya's work is part of a plan by the U.S. Department of Energy to consolidate the country's nuclear waste in a single proposed repository. The proposed repository is in Yucca Mountain located in a remote Nevada desert. Currently about 70,000 metric tons of spent nuclear fuel and high-level radioactive waste are divided between approximately 100 sites around the country. The undertaking, Pharkya emphasizes, is massive. To study just the corrosion aspects of the packaging, Case is collaborating with eight other universities, five national labs and Atomic Energy of Canada Limited. Even with so many players, the study will likely take several years to complete. Heading the entire group is Joe Payer, a professor of materials science and engineering at Case and Pharkya's mentor. ''I came here to have the opportunity to work with Dr. Payer, an expert in corrosion, but I didn't know specifically what I would be working on'', Pharkya recalls. ''I was pretty thrilled when I learned about the vastness of the project--my research would be just a small part of this huge topic--and the impact of the research we would be doing''.
Date: February 10, 2006
Creator: Srisuro, L.
Partner: UNT Libraries Government Documents Department

The 10,000 Year Plan

Description: Pallavi Pharkya thinks a lot about the future. Pharkya, a Ph.D. candidate in materials science and engineering, works in the area of corrosion science, predicting how materials will perform over extended periods of time. Her particular focus is a nickel-chromium-molybdenum alloy called C-22, a highly corrosion-resistant metal. Pharkya's aim is to help determine whether containers made from C-22 can be used to store high-energy nuclear waste--for 10,000 years and longer. Pharkya's work is part of a plan by the U.S. Department of Energy to consolidate the country's nuclear waste in a single proposed repository. The proposed repository is in Yucca Mountain located in a remote Nevada desert. Currently about 70,000 metric tons of spent nuclear fuel and high-level radioactive waste are divided between approximately 100 sites around the country. The undertaking, Pharkya emphasizes, is massive. To study just the corrosion aspects of the packaging, Case is collaborating with eight other universities, five national labs and Atomic Energy of Canada Limited. Even with so many players, the study will likely take several years to complete. Heading the entire group is Joe Payer, a professor of materials science and engineering at Case and Pharkya's mentor. ''I came here to have the opportunity to work with Dr. Payer, an expert in corrosion, but I didn't know specifically what I would be working on'', Pharkya recalls. ''I was pretty thrilled when I learned about the vastness of the project--my research would be just a small part of this huge topic--and the impact of the research we would be doing''.
Date: February 10, 2006
Creator: Srisaro, L.
Partner: UNT Libraries Government Documents Department

The 10-20-30 Plan and Persistent Poverty Counties

Description: This report discusses the 10-20-30 plan of reallocating funds in rural development programs toward counties with systemic poverty levels defined as 20% of the population being at or below poverty level for 30 years. This report explains why targeting funds to persistent poverty counties might be of interest, how "persistent poverty" is defined and measured, and how different interpretations of the definition and different data source selections could yield different lists of counties identified as persistently poor. This report does not compare the 10-20-30 plan's advantages and disadvantages against other policy options, nor does it examine the range of programs or policy goals for which the 1020-30 plan might be an appropriate policy tool.
Date: February 8, 2018
Creator: Dalaker, Joseph
Partner: UNT Libraries Government Documents Department

10 kW SOFC Power System Commercialization

Description: Cummins Power Generation (CPG) as the prime contractor and SOFCo-EFS Holdings LLC (SOFCo), as their subcontractor, teamed under the Solid-state Energy Conversion Alliance (SECA) program to develop 3-10kW solid oxide fuel cell systems for use in recreational vehicles, commercial work trucks and stand-by telecommunications applications. The program goal is demonstration of power systems that meet commercial performance requirements and can be produced in volume at a cost of $400/kW. This report summarizes the team's activities during the seventh six-month period (July-December 2005) of the four-year Phase I effort. While there has been significant progress in the development of the SOFC subsystems that can support meeting the program Phase 1 goals, the SOFCo ceramic stack technology has progressed significantly slower than plan and CPG consider it unlikely that the systemic problems encountered will be overcome in the near term. SOFCo has struggled with a series of problems associated with inconsistent manufacturing, inadequate cell performance, and the achievement of consistent, durable, low resistance inter-cell connections with reduced or no precious materials. A myriad of factors have contributed to these problems, but the fact remains that progress has not kept pace with the SECA program. A contributing factor in SOFCo's technical difficulties is attributed to their significantly below plan industry cost share spending over the last four years. This has resulted in a much smaller SOFC stack development program, has contributed to SOFCo not being able to aggressively resolve core issues, and clouds their ability to continue into a commercialization phase. In view of this situation, CPG has conducted an independent assessment of the state-of-the-art in planar SOFC's stacks and have concluded that alternative technology exists offering the specific performance, durability, and low cost needed to meet the SECA objectives. We have further concluded that there is insufficient evidence to reliably predict that ...
Date: February 1, 2006
Creator: Norrick, Dan; Palmer, Brad; Vesely, Charles; Barringer, Eric; Budge, John; DeBellis, Cris et al.
Partner: UNT Libraries Government Documents Department

10 kW SOFC POWER SYSTEM COMMERCIALIZATION

Description: The program is organized into three developmental periods. In Phase 1 the team will develop and demonstrate a proof-of-concept prototype design and develop a manufacturing plan to substantiate potential producibility at a target cost level of $800/kW factory manufacturing cost. Phase 2 will further develop the design and reduce the manufacturing cost to a level of $600 kW. Depending on an assessment of the maturity of the technology at the end of Phase 1, Phase 2 may be structured and supplemented to provide a limited production capability. Finally, in Phase 3, a full Value Package Introduction (VPI) Program will be integrated into the SECA program to develop a mass-producible design at a factory cost of $400/kW with full cross-functional support for unrestricted commercial sales. The path to market for new technology products in the Cummins system involves two processes. The first is called Product Preceding Technology, or PPT. The PPT process provides a methodology for exploring potentially attractive technologies and developing them to the point that they can be reliably scheduled into a new product development program with a manageable risk to the product introduction schedule or product quality. Once a technology has passed the PPT gate, it is available to be incorporated into a Value Package Introduction (VPI) Program. VPI is the process that coordinates the cross-functional development of a fully supported product. The VPI Program is designed to synchronize efforts in engineering, supply, manufacturing, marketing, finance, and product support areas in such a way that the product, when introduced to the market, represents the maximum value to the customer.
Date: February 1, 2004
Creator: Norrick, Dan; Palmer, Brad; Vesely, Charles; Barringer, Eric; DeBellis, Cris; Goettler, Rich et al.
Partner: UNT Libraries Government Documents Department

14-Inch Swing Check Valve Test

Description: The check valve for the Hallam Power Reactor uses a knife-edge bearing for the flapper in place of the usual journal-type bearing. Mechanical cycling in sodium at 600 deg F was used to check operation of this bearing. A total of 309 mechanical cycles was completed with no apparent malfunctioning of the valve. Measured leskage rates were 0.46 gpm at 0.93 psig, 0.73 gpm at 3.4 psig. and 0.32 gpm at 5.9 psig. (M.C.G.)
Date: February 10, 1960
Creator: Cygan, R.
Partner: UNT Libraries Government Documents Department

The 17 keV neutrino and neutrino tagging

Description: P-788 at FNAL proposed to search for neutrino oscillations in a tagged neutrino line. A K{sub L} beam and the decay modes K{sub L} {yields} {pi}{mu}{nu}{sub {mu}} and K {sub L} {yields} {pi}e{nu}{sub e} provides the neutrino flux. An upstream tagging spectrometer then identifies the hadron and lepton and reconstructs the K{sub L} decay; the lepton identification will specifies the neutrino as {nu}{sub e} or {nu}{sub {mu}} and distinguishes {nu} from {bar {nu}} at the decay vertex. A neutrino detector modeled after an existing deep-inelastic scattering spectrometer (rates have been worked out for the CCFR apparatus) can be used to associate the K{sub L} with a neutrino interaction, measure the neutrino energy, and analyze outgoing muons. Monte Carlo studies show that 30K {nu}{sub e} and 20K {nu}{sub {mu}} could be obtained in two fixed target runs at the Tevatron.
Date: February 1, 1992
Creator: Bernstein, R.H.
Partner: UNT Libraries Government Documents Department

The 17 keV neutrino and neutrino tagging

Description: P-788 at FNAL proposed to search for neutrino oscillations in a tagged neutrino line. A K{sub L} beam and the decay modes K{sub L} {yields} {pi}{mu}{nu}{sub {mu}} and K {sub L} {yields} {pi}e{nu}{sub e} provides the neutrino flux. An upstream tagging spectrometer then identifies the hadron and lepton and reconstructs the K{sub L} decay; the lepton identification will specifies the neutrino as {nu}{sub e} or {nu}{sub {mu}} and distinguishes {nu} from {bar {nu}} at the decay vertex. A neutrino detector modeled after an existing deep-inelastic scattering spectrometer (rates have been worked out for the CCFR apparatus) can be used to associate the K{sub L} with a neutrino interaction, measure the neutrino energy, and analyze outgoing muons. Monte Carlo studies show that 30K {nu}{sub e} and 20K {nu}{sub {mu}} could be obtained in two fixed target runs at the Tevatron.
Date: February 1, 1992
Creator: Bernstein, R. H.
Partner: UNT Libraries Government Documents Department

20% Wind by 2030: Overcoming the Challenges in West Virginia

Description: Final Report for '20% Wind by 2030: Overcoming the Challenges in West Virginia'. The objective of this project was to examine the obstacles and constraints to the development of wind energy in West Virginia as well as the obstacles and constraints to the achievement of the national goal of 20% wind by 2030. For the portion contracted with WVU, there were four tasks in this examination of obstacles and constraints. Task 1 involved the establishment of a Wind Resource Council. Task 2 involved conducting limited research activities. These activities involved an ongoing review of wind energy documents including documents regarding the potential for wind farms being located on reclaimed surface mining sites as well as other brownfield sites. The Principal Investigator also examined the results of the Marshall University SODAR assessment of the potential for placing wind farms on reclaimed surface mining sites. Task 3 involved the conducting of outreach activities. These activities involved working with the members of the Wind Resource Council, the staff of the Regional Wind Energy Institute, and the staff of Penn Future. This task also involved the examination of the importance of transmission for wind energy development. The Principal Investigator kept informed as to transmission developments in the Eastern United States. The Principal Investigator coordinated outreach activities with the activities at the Center for Business and Economic Research at Marshall University. Task 4 involved providing technical assistance. This task involved the provision of information to various parties interested in wind energy development. The Principal Investigator was available to answer requests from interested parties regarding in formation regarding both utility scale as well as small wind development in West Virginia. Most of the information requested regarded either the permitting process for wind facilities of various sizes in the state or information regarding the wind potential in ...
Date: February 15, 2012
Creator: Mann, Patrick & Risch, Christine
Partner: UNT Libraries Government Documents Department

21-PWR Waste Package Side and End Impacts

Description: The objective of this calculation is to determine the structural response of a 21-Pressurized Water Reactor (PWR) spent nuclear fuel waste package impacting an unyielding surface. A range of initial velocities and initial angles between the waste package and the unyielding surface is studied. The scope of this calculation is limited to estimating the area of the outer shell (OS) where the residual stress exceeds a given limit (hereafter ''damaged area''). The stress limit is defined as a fraction of the yield strength of the OS material, Alloy 22 (SB-575 N06022), at the appropriate temperature. The design of the 21-PWR waste package used in this calculation is that defined in Reference 8. However, a value of 4 mm was used for the gap between the inner shell and the OS, and the thickness of the OS was reduced by 2 mm. The sketch in Attachment I provides additional information not included in Reference 8. All obtained results are valid for this design only. This calculation is associated with the waste package design and was performed by the Specialty Analyses and Waste Package Design Section. The waste package (i.e. uncanistered spent nuclear fuel disposal container) is classified as Quality Level 1.
Date: February 27, 2003
Creator: Delabrosse, V.
Partner: UNT Libraries Government Documents Department