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Mechanism of catalytic gasification of coal char. Quarterly technical report No. 5, October 1 to December 31, 1981

Description: The purpose of this study is to determine the mechanisms involved in the catalytic reactions of coal char and to identify the specific reaction steps and the parameters that control the catalytic process. The mode of action of the catalyst can be viewed in two ways. In one view, the catalyst participates in a reduction/oxidation cycle. The initial reaction between the carbon and the catalyst reduces the KOH to potassium accompanied by the gaseous reactant (H/sub 2/O or CO/sub 2/), producing fur… more
Date: February 26, 1982
Creator: Wood, B. J.; Sancier, K. M.; Sheridan, D. R.; Chan, B. L. & Wise, H.
Partner: UNT Libraries Government Documents Department
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Acclerator R&D for a Linear Collider

Description: The goal of this project was to perform simulations of beam transport in linear colliders, with an emphasis on emittance dilution, spin polarization transport, and development and testing of beam based tuning algorithms. Our simulations are based on an existing object-oriented particle-tracking library, Bmad. To facilitate the efficient development of simulations, an accelerator design and analysis program based on Bmad has been developed called Tao (Tool for Accelerator Optics). The three beam… more
Date: November 26, 2008
Creator: Rubin, D.L.; Dugan, G.; Gibbons, L.; Palmer, M.; Patterson, R.; Sagan, D. et al.
Partner: UNT Libraries Government Documents Department
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Spectroscopy of neutron-rich palladium and cadmium isotopes near A=120

Description: New high-spin levels have been identified in the nucleus {sup 120}Pd from analysis of the coincidence gamma rays observed in the {sup 238}U({alpha}, f{gamma}{gamma}{gamma}) reaction. Recoiling fragments were detected with the Rochester heavy-ion detector array, CHICO, in coincidence with gamma-rays using Gammasphere. An A=110-130 mass-gated {gamma} - {gamma} - {gamma} cube from this experiment was constructed and analyzed for coincident gamma-rays in several nuclei near A=120. New results for n… more
Date: February 26, 2008
Creator: Stoyer, M A & Walters, W B
Partner: UNT Libraries Government Documents Department
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Mn l3,2 x-ray absorption spectroscopy and magnetic circulardichroism in ferromagnetic ga1-xmnxp

Description: We have measured the X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) at the Mn L{sub 3,2} edges in ferromagnetic Ga{sub 1-x}Mn{sub x}P films for 0.018 {le} x {le} 0.042. Large XMCD asymmetries at the L{sub 3} edge indicate significant spin-polarization of the density of states at the Fermi energy. The spectral shapes of the XAS and XMCD are nearly identical with those for Ga{sub 1-x}Mn{sub x}As indicating that the hybridization of Mn d states and anion p states is similar in… more
Date: July 26, 2007
Creator: Stone, P.R.; Scarpulla, M.A.; Farshchi, R.; Sharp, I.D.; Beeman,J.W.; Yu, K.M. et al.
Partner: UNT Libraries Government Documents Department
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Reduction of pertechnetate by acetohydroxamic acid: Formation of [TcNO(AHA)2(H2O)]+ and implications for the UREX process.

Description: 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 ty… more
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.
Partner: UNT Libraries Government Documents Department
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Future BNL plans for a polarized electron-ion collider (eRHIC)

Description: To provide polarized electron-proton collisions of {radical}s = 100 GeV; addition of a 10 GeV electron accelerator to the existing RHIC facility is currently under study. Two design lines are under consideration: a self-polarizing electron ring, and an energy recovery linac. While the latter provides significantly higher luminosities, it is technologically very challenging. We present both design approaches and discuss their advantages and limitations.
Date: July 26, 2009
Creator: Montag, C.
Partner: UNT Libraries Government Documents Department
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Forward Neutral Pion Transverse Single Spin Asymmetries in p+p Collisions at sqrt s = 200 GeV

Description: We report precision measurements of the Feynman-x (x{sub F}) dependence, and first measurements of the transverse momentum (p{sub T}) dependence, of transverse single spin asymmetries for the production of {pi}{sup 0} mesons from polarized proton collisions at {radical}s = 200 GeV. The x{sub F} dependence of the results are in fair agreement with perturbative QCD (pQCD) model calculations that identify orbital motion of quarks and gluons within the proton as the origin of the spin effects. Resu… more
Date: November 26, 2008
Creator: STAR Collaboration
Partner: UNT Libraries Government Documents Department
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Experimental Mathematics and Mathematical Physics

Description: One of the most effective techniques of experimental mathematics is to compute mathematical entities such as integrals, series or limits to high precision, then attempt to recognize the resulting numerical values. Recently these techniques have been applied with great success to problems in mathematical physics. Notable among these applications are the identification of some key multi-dimensional integrals that arise in Ising theory, quantum field theory and in magnetic spin theory.
Date: June 26, 2009
Creator: Bailey, David H.; Borwein, Jonathan M.; Broadhurst, David & Zudilin, Wadim
Partner: UNT Libraries Government Documents Department
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Collins Fragmentation and the Single Transverse Spin Asymmetry

Description: We study the Collins mechanism for the single transverse spin asymmetry in the collinear factorization approach. The correspondent twist-three fragmentation function is identified. We show that the Collins function calculated in this approach is universal.We further examine its contribution to the single transverse spin asymmetry of semi-inclusive hadron production in deep inelastic scattering and demonstrate that the transverse momentum dependent and twist-three collinear approaches are consis… more
Date: March 26, 2009
Creator: Yuan, Feng & Zhou, Jian
Partner: UNT Libraries Government Documents Department
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Spin Tracking Studies for Beam Polarization Preservation in theNLC Main Damping Rings

Description: We report results from studies of spin dynamics in the NLC Main Damping. Our studies have been based on spin tracking particles through the lattice under a range of conditions. We find that there are a number of spin resonances close to the nominal operating energy of 1.98 GeV; however, the effects of the resonances are weak, and the widths are narrow. We do not expect that any significant depolarization of the beam will occur during the store time.
Date: July 26, 2004
Creator: Wolski, Andrzej & Bates, Daniel
Partner: UNT Libraries Government Documents Department
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PROCEEDINGS FROM RIKEN-BNL RESEARCH CENTER WORKSHOP: PARITY-VIOLATING SPIN ASYMMETRIES AT RHIC.

Description: The RHIC spin program is now fully underway. Several runs have been successfully completed and are producing exciting first results. Luminosity and polarization have improved remarkably and promising advances toward the higher RHIC energy of {radical}s = 500 GeV have been made. At this energy in particular, it will become possible to perform measurements of parity-violating spin asymmetries. Parity violation occurs in weak interactions, and in combination with the unique polarization capabiliti… more
Date: April 26, 2007
Creator: Vogelsang, W.; Perdekamp, M. & Surrow, B.
Partner: UNT Libraries Government Documents Department
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27Al and 1H Solid State NMR Studies Show Evidence of TiAl3 and TiH2 in Ti-doped NaAlH4

Description: Previous X-ray Diffraction (XRD) and Nuclear Magnetic Resonance (NMR) studies on Ti-doped NaAlH{sub 4} revealed the reaction products of two heavily doped (33.3 at.%) samples that were solvent-mixed and mechanically-milled. This investigation revealed that nano-crystalline or amorphous Al{sub 2}O{sub 3} forms from the possible coordination of aluminum with oxygen atom of the furan ring system from added tetrahydrofuran (THF) in the solvent-mixed sample, and that TiAl{sub 3} forms in mechanicall… more
Date: May 26, 2005
Creator: Herberg, J; Maxwell, R & Majzoub, E
Partner: UNT Libraries Government Documents Department
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Limits on superconductivity-related magnetization in Sr 2RuO 4 and PrOs 4Sb 12 from scanning SQUID microscopy

Description: We present scanning SQUID microscopy data on the superconductors Sr{sub 2}RuO{sub 4} (T{sub c} = 1.5 K) and PrOs{sub 4}Sb{sub 12} (T{sub c} = 1.8 K). In both of these materials, superconductivity-related time-reversal symmetry-breaking fields have been observed by muon spin rotation; our aim was to visualize the structure of these fields. However in neither Sr{sub 2}RuO{sub 4} nor PrOs{sub 4}Sb{sub 12} do we observe spontaneous superconductivity-related magnetization. In Sr{sub 2}RuO{sub 4}, ma… more
Date: August 26, 2010
Creator: Moler, Kathryn
Partner: UNT Libraries Government Documents Department
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Topological Insulators and Nematic Phases from Spontaneous Symmetry Breaking in

Description: We investigate the stability of a quadratic band-crossing point (QBCP) in 2D fermionic systems. At the non-interacting level, we show that a QBCP exists and is topologically stable for a Berry flux {-+}2{pi}, if the point symmetry group has either fourfold or sixfold rotational symmetries. This putative topologically stable free-fermion QBCP is marginally unstable to arbitrarily weak shortrange repulsive interactions. We consider both spinless and spin-1/2 fermions. Four possible ordered states… more
Date: May 26, 2010
Creator: Sun, K.
Partner: UNT Libraries Government Documents Department
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4th-International Symposium on Ultrafast Surface Science - Final Report

Description: The 4-th International Symposium on Ultrafast Surface Dynamics (UDS4) was held at the Telluride Summer Research Center on June 22-27, 2003. The International Organizing Committee consisting of Hrvoje Petek (USA), Xiaoyang Zhu (USA), Pedro Echenique (Spain) and Maki Kawai (Japan) brought together a total of 51 participants 16 of whom were from Europe, 10 from Japan, and 25 from the USA. The focus of the conference was on ultrafast electron or light induced processes at well-defined surfaces. Ult… more
Date: January 26, 2005
Creator: Petek, Hrvoje
Partner: UNT Libraries Government Documents Department
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Free-Spinning Tunnel Investigation of a 1/20-Scale Model of the Douglas X-3 Airplane

Description: Report discussing the spin and spin-recovery characteristics of a model of the Douglas X-3 airplane in a free-spinning tunnel. The pitching-moment characteristics of the scale model were not found to be typical of larger scale results. The results indicated that at an altitude range of 15,000 to 30,000 feet, the X-3 will not exhibit unusual trim tendencies and it will be difficult to obtain erect spins unless the ailerons are full with the spin.
Date: December 26, 1951
Creator: Hultz, Burton E.
Partner: UNT Libraries Government Documents Department
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Super-B Project Overview

Description: The SuperB project aims at the construction of an asymmetric very high luminosity B-Factory on the Frascati/Tor Vergata (Italy) area, providing a uniquely sensitive probe of New Physics in the flavour sector of the Standard Model. The luminosity goal of 10{sup 36} cm{sup -2} s{sup -1} can be reached with a new collision scheme with 'large Piwinski angle' (LPA) and the use of 'crab waist sextupoles' (CW). A LPA&CW Interaction Region (IR) has been successfully tested at the DA{Phi}NE {Phi}-Fa… more
Date: August 26, 2010
Creator: Biagini, M.E.; Boni, R.; Boscolo, M.; Demma, T.; Drago, A.; Guiducci, S. et al.
Partner: UNT Libraries Government Documents Department
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Spectromicroscopy study of interfacial Co/NiO(001)

Description: Photoemission electron microscopy (PEEM) with linearly polarized x-rays is used to determine the orientation of antiferromagnetic domains by monitoring the relative peak intensities at the 3d transition metal L{sub 2} absorption edge. In such an analysis the orientations of the x-ray polarization E and magnetization H with respect to the crystalline axes has to be taken into account. We address this problem by presenting a general expression of the angular dependence for both x-ray absorption s… more
Date: September 26, 2010
Creator: van der Laan, Gerrit; Telling, Neil; Potenza, Alberto; Dhesi, Sarnjeet & Arenholz, Elke
Partner: UNT Libraries Government Documents Department
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Measurement of Branching Fractions and Charge Asymmetries in B Decays to an eta Meson and a K* Meson

Description: The authors present measurements of branching fractions and charge asymmetries for the decays B {yields} {eta}K*, where K8 indicates a spin 0, 1, or 2 K {pi} system. The data sample corresponds to 344 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. They measure the branching fractions (in units of 10{sup -6}): {Beta}(B{sup 0} {yields} {eta}K*{sup 0}(892)) = 16.5 {+-} 1.1 {+-} 0.8, {Beta}(B{sup +} {yields} {eta}K*{su… more
Date: September 26, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
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Matrix Formalism for Spin Dynamics Near a Single Depolarization Resonance

Description: A matrix formalism is developed to describe the spin dynamics in a synchrotron near a single depolarization resonance as the particle energy (and therefore its spin precession frequency) is varied in a prescribed pattern as a function of time such as during acceleration. This formalism is first applied to the case of crossing the resonance with a constant crossing speed and a finite total step size, and then applied also to other more involved cases when the single resonance is crossed repeated… more
Date: October 26, 2005
Creator: Chao, Alexander W.
Partner: UNT Libraries Government Documents Department
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(A Neutron Scattering Experiment to Study the High-Energy Spin Dynamics of the Itinerant Antiferromagnet Mn Sub 90 Cu Sub 10 )

Description: The traveler performed a neutron scattering experiment to study the high-energy spin dynamics of the itinerant antiferromagnet. This experiment was conducted at a unique instrument located at the hot-neutron source at the ILL. The traveler also held various scientific discussions with ILL research staff members and visiting scientists.
Date: October 26, 1990
Creator: Fernandez-Baca, J. A.
Partner: UNT Libraries Government Documents Department
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