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Theory of high-T{sub c} cuprates based on experimental evidence.

Description: A model of superconductivity in layered high-temperature superconducting cuprates is proposed, based on the extended saddle point singularities in the electron spectrum, weak screening of the Coulomb interaction and phonon-mediated interaction between electrons plus a small short-range repulsion of Hund's, or spin-fluctuation, origin. This permits to explain the large values of T{sub c}, features of the isotope effect on oxygen and copper, the existence of two types of the order parameter, the peak in the inelastic neutron scattering, the positive curvature of the upper critical field, as function of temperature etc.
Date: August 17, 1999
Creator: Abrikosov, A. A.
Partner: UNT Libraries Government Documents Department
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Wind Resource Development Project for Armenia

Description: Armenia has few proven reserves of natural energy and is dependent on long, unreliable transport lines for oil and gas. Preliminary studies indicate that the wind energy potential in Armenia is more than 500 megawatts (MW), assuming a reasonable fraction of 10% of the land area in the high-wind zones. Over the long term, the Armenian government intends to meet 8%--10% of its electric consumption needs by grid-connected wind turbines. The goals of this project are to enhance Armenia's energy security, mitigate the environmental damage of conventional sources of energy, reduce future carbon dioxide emissions, build an environmentally sound and sustainable model for economic development, and promote trade between the U.S. and Armenia. The project is being funded by the Cafesjian Family Foundation, a private foundation based in the United States in Naples, Florida, with the participation of Ecotrade, Inc. of Glendale, California. The National Renewable Energy Laboratory (NREL) is providing technical assistance. As part of the wind energy development project, the authors conducted a preliminary wind-energy resource assessment for some regions in Armenia. This activity provided valuable information needed to facilitate the commercialization of wind farms in Armenia and to lay the groundwork for subsequent wind resource activities. This paper presents the wind resource monitoring results (1999--2000) for the candidate site. Preliminary assessment identified areas with good-to-excellent wind resource potential.
Date: August 17, 2000
Creator: Adamian, S.; Manoukian, L.; Lalayan, A. (Ecotrade, Inc.) & Gevorgian, V. (National Renewable Energy Laboratory)
Partner: UNT Libraries Government Documents Department
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HRT-CP INSTRUMENTATION DESIGN MANUAL

Description: The installation and design of the HRT-Core Processing Plant are described in detail so that operation and maintenance of the plant may be made more effective. Process instruments will be described fully, but auxiliary instrumentation such as pressure gauges, rotameters, etc. will not be mentioned. Where detailed questions arise as to electrical circuitry or instrument connections, the drawings and specification sheets should be consulted. (auth)
Date: August 17, 1956
Creator: Adams, R.K.
Partner: UNT Libraries Government Documents Department
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Limits on Large Extra Dimensions Based on Observations of Neutron Stars with the Fermi-LAT

Description: We present limits for the compactification scale in the theory of Large Extra Dimensions (LED) proposed by Arkani-Hamed, Dimopoulos, and Dvali. We use 11 months of data from the Fermi Large Area Telescope (Fermi-LAT) to set gamma ray flux limits for 6 gamma-ray faint neutron stars (NS). To set limits on LED we use the model of Hannestad and Raffelt (HR) that calculates the Kaluza-Klein (KK) graviton production in supernova cores and the large fraction subsequently gravitationally bound around the resulting NS. The predicted decay of the bound KK gravitons to {gamma}{gamma} should contribute to the flux from NSs. Considering 2 to 7 extra dimensions of the same size in the context of the HR model, we use Monte Carlo techniques to calculate the expected differential flux of gamma-rays arising from these KK gravitons, including the effects of the age of the NS, graviton orbit, and absorption of gamma-rays in the magnetosphere of the NS. We compare our Monte Carlo-based differential flux to the experimental differential flux using maximum likelihood techniques to obtain our limits on LED. Our limits are more restrictive than past EGRET-based optimistic limits that do not include these important corrections. Additionally, our limits are more stringent than LHC based limits for 3 or fewer LED, and comparable for 4 LED. We conclude that if the effective Planck scale is around a TeV, then for 2 or 3 LED the compactification topology must be more complicated than a torus.
Date: August 17, 2012
Creator: Ajello, M.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R. et al.
Partner: UNT Libraries Government Documents Department
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Overview of Grand Unified Models and their predictions for neutrino oscillations

Description: A brief overview of Grand Unified Models is presented with some attention paid to their predictions for neutrino oscillations. Given the well-known features of the two non-unified standard models, SM and MSSM, a listing of the features of classes of unified models is given, where a GUT flavor symmetry and/or family symmetry are introduced to reduce the number of model parameters. Some general remarks are then made concerning the type of predictions that follow for the neutrino masses and mixings.
Date: August 17, 2000
Creator: Albright, Carl H.
Partner: UNT Libraries Government Documents Department
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Gray Wolves Under the Endangered Species Act (ESA): Distinct Population Segments and Experimental Populations

Description: This report analyzes the Endangered Species Act (ESA) as it applies to gray wolf wolves and, in particular, to their treatment as experimental populations (Ex Pops) and distinct population segments (DPSs).
Date: August 17, 2011
Creator: Alexander, Kristina & Corn, M. L.
Partner: UNT Libraries Government Documents Department
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Synchrotron radiation power calculations and bending radius choice for LER (Low Energy Ring)

Description: This note will discuss ways of choosing a bending radius and synchrotron radiation absorber design. We would like to decrease the synchrotron radiation power density on the absorber's surfaces, yet we would like to reduce the LER's bending radius for better matching with the HER (beam-beam interaction criteria). We will consider two cases, both based on the PEP structure. One with 96 periods, containing 1 bending magnet per period and the other 2 bends per period. The case of synchrotron radiation absorbers outside of the bending magnet will considered also. 2 refs., 13 figs.
Date: August 17, 1990
Creator: Alexandrov, A.; Hutton, A. & Logatchev, P.
Partner: UNT Libraries Government Documents Department
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Investigation of a triangular wing in conjunction with a fuselage and horizontal tail to determine downwash and longitudinal-stability characteristics: transonic bump method

Description: Report presenting the results of an experimental investigation of the downwash and longitudinal stability characteristics of a semispan, triangular-wing airplane model with a horizontal tail. Lift, drag, and pitching-moment data re presented for the wing-fuselage combination. Results indicated that the model with the tail on or below the wing-chord plane possessed satisfactory stability characteristics throughout the test range of lift coefficient.
Date: August 17, 1951
Creator: Allen, Edwin C.
Partner: UNT Libraries Government Documents Department
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LED-induced fluorescence diagnostics for turbine and combustion engine thermometry

Description: Fluorescence from phosphor coatings is the basis of an established technique for measuring temperature in a wide variety of turbine and combustion engine applications. Example surfaces include blades, vanes, combustors, intake valves, pistons, and rotors. Many situations that are remote and noncontact require the high intensity of a laser to illuminate the phosphor, especially if the surface is moving. Thermometric resolutions of 0.1 C are obtainable, and some laboratory versions of these systems have been calibrated against NIST standards to even higher precision. To improve the measurement signal-to-noise ratio, synchronous detection timing has been used to repeatedly interrogate the same blade in a high speed rotating turbine. High spatial resolution can be obtained by tightly focusing the interrogation beam in measurements of static surfaces, and by precise differential timing of the laser pulses on rotating surfaces. We report here the use of blue light emitting diodes (LEDs) as a n illumination source for producing useable fluorescence from phosphors for temperature measurements. An LED can excite most of the same phosphors used to cover the temperature range from 8 to 1400 C. The advantages of using LEDs are obvious in terms of size, power requirements, space requirements and cost. There can also be advantages associated with very long operating lifetimes, wide range of available colors, and their broader emission bandwidths as compared to laser diodes. Temperature may be inferred either from phase or time-decay determinations.
Date: August 17, 2001
Creator: Allison, S. W.
Partner: UNT Libraries Government Documents Department
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Development and Coil Fabrication for the LARP 3.7-m Long Nb3Sn Quadrupole

Description: The U.S. LHC Accelerator Research Program (LARP) has started the fabrication of 3.7-m long Nb{sub 3}Sn quadrupole models. The Long Quadrupoles (LQ) are 'Proof-of-Principle' magnets which are to demonstrate that Nb{sub 3}Sn technology is mature for use in high energy particle accelerators. Their design is based on the LARP Technological Quadrupole (TQ) models, developed at FNAL and LBNL, which have design gradients higher than 200 T/m and an aperture of 90 mm. The plans for the LQ R&D and a design update are presented and discussed in this paper. The challenges of fabricating long accelerator-quality Nb{sub 3}Sn coils are presented together with the solutions adopted for the LQ coils (based on the TQ experience). During the fabrication and inspection of practice coils some problems were found and corrected. The fabrication at BNL and FNAL of the set of coils for the first Long Quadrupole is in progress.
Date: August 17, 2008
Creator: Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S. et al.
Partner: UNT Libraries Government Documents Department
open access

The First Day of a New Congress: A Guide to Proceedings on the House Floor

Description: The House of Representatives follows a well established routine on the opening day of a new Congress. The proceedings include election of the Speaker, swearing in its members, election of administrative officers, and adoption of rules of procedure. Also, resolutions assigning its members to committees may be adopted. The House must take these actions at the beginning of each new Congress because it is not a continuing body. Article 1, Section 2 of Constitution sets terms for Members of the House at two years. Thus, the House ends at the conclusion of each two-year Congress and must reconstitute itself at the beginning of a new Congress. This report focuses on the floor activities of the House during its first formal session in a new Congress, and serves as a guide for participating in or watching those proceedings.
Date: August 17, 2005
Creator: Amer, Mildred L.
Partner: UNT Libraries Government Documents Department
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Muons and neutrinos at high-energy accelerators

Description: Background levels in detectors and radiation problems at future colliders--whether pp, e{sup +}e{sup {minus}} or {mu}{sup +}{mu}{sup {minus}} are in large part determined by the presence of muons. Neutrinos from muon decay at muon colliders or storage rings are highly collimated and propagate outward within a narrowdisk in which significant radiation doses persist out to very large distances. This paper highlights physics models and Monte Carlo algorithms developed mainly for studying these problems as well as some typical results.
Date: August 17, 2000
Creator: Andreas Van Ginneken, Sergei Striganov and Nikolai Mokhov
Partner: UNT Libraries Government Documents Department
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Phase I Archaeological Survey of Parcel ED-3 and Historic Assessement of the Happy Valley Worker Camp Roane County, Tennessee

Description: Parcel ED-3 was the location of a portion of 'Happy Valley', a temporary worker housing area occupied from 1943 to 1947 during the construction of the K-25 Oak Ridge Gaseous Diffusion Plant. The project was carried out under subcontract for the Department of Energy. The survey report will be used in the preparation of an Environmental Assessment under the National Environmental Policy Act (NEPA). New South Associates conducted a Phase I Archaeological Survey of Parcel ED-3 at the US Department of Energy's Oak Ridge Reservation in Roane County, Tennessee. The survey was conducted in two parts. The first survey was carried out in 2008 and covered an area measuring approximately 110 acres. The second survey took place in 2009 and focused on 72 acres west of the first survey area. The objective of the surveys was to identify any archaeological remains associated with Happy Valley and any additional sites on the property and to assess these sites for National Register eligibility. New South Associates also conducted a historic assessment to gather information on Happy Valley. This historic assessment was used in conjunction with the archaeological survey to evaluate the significance of the Happy Valley site. Archaeological remains of Happy Valley were located throughout the parcel, but no additional sites were located. The official state site number for Happy Valley is 40RE577. During the two surveys a total of 13 artifact concentrations, 14 isolated finds, and 75 structural features were located. Due to the Happy Valley's stron gassociation with the Manhattan Project, the site is recommended eligible for the National Register of Historic Places under Criterion A.
Date: August 17, 2009
Creator: Associates, New South
Partner: UNT Libraries Government Documents Department
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Seismic studies of the San Francisco-Oakland Bay Bridge

Description: Computational simulation plays a central role in the engineering analysis and design of major bridge structures and accurate simulations are essential for the development of earthquake resistant and economical structural designs. This paper describes new methodologies and computational tools which have recently been developed for simulating earthquake ground motions and the seismic response of cable supported bridges. The simulation tools are described and an example application for an important long-span suspension bridge is demonstrated. The application portion of the study has particular focus on the potential damaging effects of long period displacement pulses and permanent ground displacements which can occur when a bridge is located in the near-field of a major earthquake fault.
Date: August 17, 1999
Creator: Astaneh-Asl, A.; Larsen, S. & McCallen, D.
Partner: UNT Libraries Government Documents Department
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Application of adaptive optics for controlling the NIF laser performance and spot size

Description: The National Ignition Facility (NIF) laser will use a 192-beam multi-pass architecture capable of delivering several MJ of UV energy in temporal pulse formats varying from sub-ns square to 20 ns precisely-defined high-contrast shapes. Each beam wavefront will be subjected to effects of optics inhomogeneities, figuring errors, mounting distortions, prompt and slow thermal effects from flashlamps, driven and passive air-path turbulence, and gravity-driven deformations. A 39-actuator intra-cavity deformable mirror, controlled by data from a 77-lenslet Hartman sensor will be used to correct these wavefront aberrations and thus to assure that stringent farfield spot requirements are met. We have developed numerical models for the expected distortions, the operation of the adaptive optic system, and the anticipated effects on beam propagation, component damage, frequency conversion, and target-plane energy distribution. These models have been extensively validated against data from LLNL's Beamlet, and Amplab lasers. We review the expected beam wavefront aberrations and their potential for adverse effects on the laser performance, describe our model of the corrective system operation, and display our predictions for corrected-beam operation of the NI
Date: August 17, 1998
Creator: Auerbach, J.; Bliss, E.; Henesian, M.; Lawson, J.; Manes, K.; Renard, P. et al.
Partner: UNT Libraries Government Documents Department
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Design and progress toward a multi-conjugate adaptive optics system for distributed aberration correction

Description: This article investigates the use of a multi-conjugate adaptive optics system to improve the field-of-view for the system. The emphasis of this research is to develop techniques to improve the performance of optical systems with applications to horizontal imaging. The design and wave optics simulations of the proposed system are given. Preliminary results from the multi-conjugate adaptive optics system are also presented. The experimental system utilizes a liquid-crystal spatial light modulator and an interferometric wave-front sensor for correction and sensing of the phase aberrations, respectively.
Date: August 17, 2004
Creator: Baker, K.; Olivier, S.; Tucker, J.; Silva, D.; Gavel, D.; Lim, R. et al.
Partner: UNT Libraries Government Documents Department
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Vadose zone microbial community structure and activity in metal/radionuclide contaminated sediments. Final technical report

Description: This final technical report describes the research carried out during the final two months of the no-cost extension ending 11/14/01. The primary goals of the project were (1) to determine the potential for transformation of Cr(VI) (oxidized, mobile) to Cr(III) (reduced, immobile) under unsaturated conditions as a function of different levels and combinations of (a) chromium, (b) nitrate (co-disposed with Cr), and (c) molasses (inexpensive bioremediation substrate), and (2) to determine population structure and activity in experimental treatments by characterization of the microbial community by signature biomarker analysis and by RT-PCR and terminal restriction fragment length polymorphism (T-RFLP) and 16S ribosomal RNA genes. It was determined early in the one-year no-cost extension period that the T-RFLP approach was problematic in regard to providing information on the identities of microorganisms in the samples examined. As a result, it could not provide the detailed information on microbial community structure that was needed to assess the effects of treatments with chromium, nitrate, and/or molasses. Therefore, we decided to obtain the desired information by amplifying (using TR-PCR, with the same primers used for T-RFLP) and cloning 16S rRNA gene sequences from the same RNA extracts that were used for T-RFLP analysis. We also decided to use a restriction enzyme digest procedure (fingerprinting procedure) to place the clones into types. The primary focus of the research carried out during this report period was twofold: (a) to complete the sequencing of the clones, and (b) to analyze the clone sequences phylogenetically in order to determine the relatedness of the bacteria detected in the samples to each other and to previously described genera and species.
Date: August 17, 2002
Creator: Balkwill, David L.
Partner: UNT Libraries Government Documents Department
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From double exchange to superexchange in charge ordering perovskite manganites

Description: The authors found dynamic ferromagnetic correlations at the room temperature in perovskite manganites which have an antiferromagnetic insulating ground state. They are replaced by antiferromagnetic correlations when the electrons order. The results indicate that the double exchange mechanism is turned off by electron localization at low temperatures.
Date: August 17, 1998
Creator: Bao, W.; Axe, J. D.; Chen, C. H.; Cheong, S. W.; Schiffer, P. & Roy, M.
Partner: UNT Libraries Government Documents Department
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Porosity in Polysilsesquioxane Xerolgels

Description: Polymerization of organotrialkoxysilanes is a convenient method for introducing organic functionality into hybrid organic-inorganic materials. However, not much is known about the effects of the organic substituent on the porosity of the resulting xerogels. In this study, we prepared a series of polysilsesquioxane xerogels from organotrialkoxysilanes, RSi(OR{sup 1}){sub 3}, with different organic groups (R = H, Me, Et dodecyl, hexadecyl, octadecyl, vinyl, chloromethyl, (p-chloromethyl) phenyl, cyanoethyl). Polymerizations of the monomers were carried out under a variety of conditions, varying monomer concentration, type of catalyst, and alkoxide substituent. The effect of the organic substituent on the sol-gel process was often dramatic. In many cases, gels were formed only at very high monomer concentration and/or with only one type of catalyst. All of the gels were processed as xerogels and characterized by scanning electron microscopy and nitrogen sorption porosimetry to evaluate their pore structure.
Date: August 17, 1999
Creator: Baugher, B.M.; Loy, D.A. & Rahimian, K.
Partner: UNT Libraries Government Documents Department
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Disaster Evacuation and Displacement Policy: Issues for Congress

Description: This report contains an overview of the issues for Congress on the disaster evacuation and displacement policy. In general, evacuation policy is set and enforced by state and local officials. However, federal policy does provide for certain aspects of civilian emergency evacuation.
Date: August 17, 2006
Creator: Bea, Keith
Partner: UNT Libraries Government Documents Department
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