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CRITICAL FIELD FOR SUPERCONDUCTIVITY AND LOW-TEMPERATURE NORMAL-STATE HEAT CAPACITY OF TUNGSTEN

Description: We have measured the critical magnetic field for superconductivity In tungsten from 5.5 to 15 mK using a {gamma}-ray anisotropy thermometer, and we have measured the heat capacity between 0.35 and 25 K. Analysis of the data gives H{sub 0} = 1.237 Oe for the 0 K critical field, T{sub c} = 16.0 mK for the critical temperature, {gamma} = 1.008 mJ/mole K{sup 2} for the coefficient of the electronic heat capacity, and {Theta}{sub 0} = 383 K for the 0 K Debye temperature. The measured values of the c… more
Date: March 1, 1973
Creator: Triplett, B. B.; Phillips, N. E.; Thorp, T. L.; Shirley, D. A. & Brewer, W. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of pressure anisotropy on plasma transport

Description: In a recent paper a new set of generalized two-field equations is derived which describes plasma transport along the field lines of a space and time dependent magnetic field. These equations are valid for collisional to weakly collisional plasmas; they reduce to the conventional fluid equations of Braginskii for highly collisional plasmas. An important feature of these equations is that the anisotropy in the ion pressure is explicitly included. In this paper, these generalized transport equatio… more
Date: March 1, 1986
Creator: Zawaideh, E.; Najmabadi, F. & Conn, R.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of inflation on anisotropic cosmologies

Description: The effects of anisotropic cosmologies on inflation are studied. By properly formulating the field equations it is possible to show that any model that undergoes sufficient inflation will become isotropic on scales greater than the horizon today. Furthermore, we shall show that it takes a very long time for anisotropies to become visible in the observable part of the Universe. It is interesting to note that the time scale will be independent of the Bianchi Model and of the initial anisotropy. 6… more
Date: March 1, 1986
Creator: Jensen, L.G. & Stein-Schabes, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Anisotropy of transverse sound in the heavy Fermian supersonductor UPt/sub 3/

Description: We report the first measurements of the attenuation of ultrasound in the basal plane of superconducting UPt/sub 3/. Transverse sound propagating along the b-axis shows a marked anisotropy in its temperature dependence when the polarization is rotated in and out of the basal plane. For polarization in the basal plane the attenuation varies linearly with temperature down to 35 mK and the slope scales as the square of the frequency. Our results appear to indicate the presence of an additional atte… more
Date: March 1, 1986
Creator: Shiveram, B. S.; Jeong, Y. H.; Rosenbaum, T. F. & Hinks, D. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling of the electron distribution based on bremsstrahlung emission during lower hybrid current drive on PLT

Description: Lower hybrid current drive requires the generation of a high energy electron tail anisotropic in velocity. Measurements of bremsstrahlung emission produced by this tail are compared with the calculated emission from reasonable model distributions. The physical basis and the sensitivity of this modeling process are described and the plasma properties of current driven discharges which can be derived from the model are discussed.
Date: March 1, 1985
Creator: Stevens, J. E.; Von Goeler, S.; Bernabei, S.; Bitter, M.; Chu, T. K.; Efthimion, P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comments on ECH current drive by asymmetric heating around the median plane (GA Technologies report No. GA-A18656, October 1986) by Tihiro Ohkawa

Description: In a recent GA report Ohkawa describes a novel electron cyclotron current-drive (ECCD) scheme. Ohkawa finds a net toroidal plasma current driven by ''up-down'' asymmetries in the electron pressure anisotropy, i.e., differences in p/sub perpendicular/ - p/sub parallel/ evaluated at the same absolute value of B between the top and bottom half of the poloidal cross-section. Such up-down asymmetries are associated with the s-dependent, first order in nu/..omega../sub b/ part of the electron distrib… more
Date: March 30, 1987
Creator: Nevins, W. M.; Cohen, R. H. & Lodestro, L. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tensor pressure tokamak equilibrium and stability

Description: We investigate the equilibrium and magnetohydrodynamic (MHD) stability of tokamaks with tensor pressure and examine, in particular, the effects of anisotropies induced by neutral beam injection. Perpendicular and parallel beam pressure components are evaluated by taking moments of a distribution function obtained from the solution of a Fokker-Planck equation that models the injection of high-energy neutral beams into a tokamak. We numerically generate D-shaped beam-induced tensor pressure equil… more
Date: March 1, 1981
Creator: Cooper, W. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stress-induced transverse isotropy in rocks

Description: The application of uniaxial pressure can induce elastic anisotropy in otherwise isotropic rock. We consider models based on two very different rock classes, granites and weakly consolidated granular systems. We show that these models share common underlying assumptions, that they lead to similar qualitative behavior, and that both provide a microscopic basis for elliptical anisotropy. In the granular case, we make experimentally verifiable predictions regarding the horizontally propagating mode… more
Date: March 28, 1994
Creator: Schwartz, L. M.; Murphy, W. F. III & Berryman, J. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Body-wave radiation patterns and AVO in transversely isotropic media

Description: It is well known that the angular dependence of reflection coefficients may be significantly distorted in the presence of elastic anisotropy. However, the influence of anisotropy on amplitude-versus-offset analysis (AVO) is not limited to reflection coefficients. AVO signatures (e.g., AVO gradient) in anisotropic media are also distorted by the redistribution of energy along the wavefront of the wave travelling down to the reflector and back up to the surface. Significant anisotropy above the t… more
Date: March 1994
Creator: Tsvankin, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ni spin switching induced by magnetic frustration in FeMn/Ni/Cu(001)

Description: Epitaxially grown FeMn/Ni/Cu(001) films are investigated by Photoemission Electron Microscopy and Magneto-Optic Kerr Effect. We find that as the FeMn overlayer changes from paramagnetic to antiferromagnetic state, it could switch the ferromagnetic Ni spin direction from out-of-plane to in-plane direction of the film. This phenomenon reveals a new mechanism of creating magnetic anisotropy and is attributed to the out-of-plane spin frustration at the FeMn-Ni interface.
Date: March 8, 2009
Creator: Wu, J.; Choi, J.; Scholl, A.; Doran, A.; Arenholz, E.; Hwang, Chanyong et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Imaging of magnetic DW injection processed in patterened Ni80Fe20 structures

Description: Magnetization reversal in patterned ferromagnetic nanowires usually occurs via domain wall (DW) nucleation and propagation from one end (or both ends) of the wire which can be significantly reduced by a large, magnetically soft pad on one of the wire ends. These 'nucleation pads' reverse at lower fields than an isolated nanowire and introduce a DW to the wire from the wire end attached to the pad. Once a critical 'injection' field is reached, the DW sweeps through the wire, reversing its magnet… more
Date: March 23, 2009
Creator: Bryan, M. T.; Basu, S.; Fry, P. W.; Schrefl, T.; Gibbs, M.R.J.; Allwood, D. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advanced Dark Energy Physics Telescope (ADEPT)

Description: In 2006, we proposed to NASA a detailed concept study of ADEPT (the Advanced Dark Energy Physics Telescope), a potential space mission to reliably measure the time-evolution of dark energy by conducting the largest effective volume survey of the universe ever done. A peer-review panel of scientific, management, and technical experts reported back the highest possible 'excellent' rating for ADEPT. We have since made substantial advances in the scientific and technical maturity of the mission des… more
Date: March 26, 2009
Creator: Bennett, Charles L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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THE ORIENTATION OF MEMBRANE BOUND RADICALS: AN EPR INVESTIGATION OF MAGNETICALLY ORDERED SPINACH CHLOROPLASTS

Description: The orientation of membrane-bound radicals in spinach chloroplasts is examined by electron paramagnetic resonance (EPR) spectroscopy of chloroplasts oriented by magnetic fields. Several of the membrane-bound radicals which possess g-tensor anisotropy display EPR signals with a marked dependence on the orientation of the membranes relative to the applied EPR field. The fraction of oxidized and reduced plastocyanin, P-700, iron-sulfur proteins A and B, and the X center, an early acceptor of Photo… more
Date: March 1, 1978
Creator: Dismukes, G. Charles & Sauer, Kenneth
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Time-Resolved Hard X-Ray Spectrometer

Description: Wired array studies are being conducted at the SNL Z accelerator to maximize the x-ray generation for inertial confinement fusion targets and high energy density physics experiments. An integral component of these studies is the characterization of the time-resolved spectral content of the x-rays. Due to potential spatial anisotropy in the emitted radiation, it is also critical to diagnose the time-evolved spectral content in a space-resolved manner. To accomplish these two measurement goals, w… more
Date: March 1, 2007
Creator: Moya, Kenneth; McKenna, Ian; Keenan, Thomas & Cuneo, Michael
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New Geophysical Technique for Mineral Exploration and Mineral Discrimination Based on Electromagnetic Methods

Description: The research during the first two years of the project was focused on developing the foundations of a new geophysical technique for mineral exploration and mineral discrimination, based on electromagnetic (EM) methods. The developed new technique is based on examining the spectral induced polarization effects in electromagnetic data using effective-medium theory and advanced methods of 3-D modeling and inversion. The analysis of IP phenomena is usually based on models with frequency dependent c… more
Date: March 9, 2009
Creator: Zhdanov, Michael S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impact of switching to the ICRP-74 neutron flux-to-dose equivalent rate conversion factors at the Sandia National Laboratory Building 818 Neutron Source Range.

Description: Sandia National Laboratories (SNL) maintains a neutron calibration facility which supports the calibration, maintenance, and repair of Radiation Protection Instruments. The SNL neutron reference fields are calibrated using the following methodology: Fluence rate is initially established by calculation using the NIST traceable source emission rate (decay corrected). Correction factors for the effects of room return or scatter, and source anisotropy are then developed by using a suitable radiatio… more
Date: March 1, 2009
Creator: Ward, Dann C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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X-ray magnetic circular dichroism and reflection anisotropy spectroscopy Kerr effect studies of capped magnetic nanowires

Description: Aligned Co wires grown on Pt(997) under ultra-high vacuum conditions have been capped successfully by the epitaxial growth of Au monolayers (ML) at room temperature. The samples were kept under vacuum except when transferring between apparatus or when making some of the measurements. No degradation of the Co wires was detected during the measurements. The magneto-optic response of the system was measured using X-ray magnetic circular dichroism (XMCD) at the Co L{sub 2,3} edge and reflection ani… more
Date: March 2, 2010
Creator: Cunniffe, J. P.; McNally, D.E.; Liberati, M.; Arenholz, E.; McGuinness, C. & McGilp, J. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Valence-state Model of Strain-dependent Mn L2,3 X-ray Magnetic Circular Dichroism from Ferromagnetic Semiconductors

Description: We present a valence-state model to explain the characteristics of a recently observed pre-edge feature in Mn L{sub 3} x-ray magnetic circular dichroism (XMCD) of ferromagnetic (Ga,Mn)As and (Al,Ga,Mn)As thin films. The prepeak XMCD shows a uniaxial anisotropy, contrary to the cubic symmetry of the main structures induced by the crystalline electric field. Reversing the strain in the host lattice reverses the sign of the uniaxial anisotropy. With increasing carrier localization, the prepeak hei… more
Date: March 30, 2010
Creator: van der Laan, G.; Edmonds, K. W.; Arenholz, E.; Farley, N. R. S. & Gallagher, B. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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KAYENTA : theory and user's guide.

Description: The physical foundations and domain of applicability of the Kayenta constitutive model are presented along with descriptions of the source code and user instructions. Kayenta, which is an outgrowth of the Sandia GeoModel, includes features and fitting functions appropriate to a broad class of materials including rocks, rock-like engineered materials (such as concretes and ceramics), and metals. Fundamentally, Kayenta is a computational framework for generalized plasticity models. As such, it in… more
Date: March 1, 2009
Creator: Brannon, Rebecca Moss (University of Utah, Salt Lake City, UT); Fossum, Arlo Frederick (BP America, Inc., Houston, TX) & Strack, Otto Eric
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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FLIP--AN IBM-704 CODE TO SOLVE THE PL AND DOUBLE-PL EQUATIONS IN SLAB GEOMETRY

Description: A method of obtaining the few-group form of the P/sub L/ and double-P/ sub L/ equations is given for slab geometry. Anisotropic scattering is allowed within specified limitations. The difference equations and associated recursion relations are discussed; the features and restrictions of FLIP are explained; and a detailed discussion of the input and output is presented. Operating intructions are given, and a sample problem is included. (auth)
Date: March 1, 1959
Creator: Anderson, B.L.; Davis, J.A.; Gelbard, E.M. & Jarvis, P.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resonance decay effects on anisotropy parameters

Description: We present the elliptic flow v{sub 2} of pions produced from resonance decays. The transverse momentum p{sub T} spectra of the parent particles are taken from thermal model fits and their v{sub 2} are fit under the assumption that they follow a number-of-constituent-quark (NCQ) scaling law expected from quark-coalescence models. The v{sub 2} of pions from resonance particle decays is found to be similar to the measured pion v{sub 2}. We also propose the measurement of electron v{sub 2} as a mea… more
Date: March 11, 2004
Creator: Dong, Xin; Esumi, S.; Sorensen, P.; Xu, Nu & Xu, Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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X-ray study of aligned magnetic stripe domains in perpendicular multilayers

Description: We have investigated the stripe domain structure and the magnetic reversal of perpendicular Co/Pt based multilayers at room temperature using magnetometry, magnetic imaging and magnetic x-ray scattering. In-plane field cycling aligns the stripe domains along the field direction. In magnetic x-ray scattering the parallel stripe domains act as a magnetic grating resulting in observed Bragg reflections up to 5th order. We model the scattering profile to extract and quantify the domain as well as d… more
Date: March 3, 2003
Creator: Hellwig, O.; Denbeaux, G. P.; Kortright, J. B. & Fullerton, Eric E.
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Partner: UNT Libraries Government Documents Department
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Deep Vs Profiling Along the Top of Yucca Mountain Using a Vibroseis Source and Surface Waves

Description: Yucca Mountain, Nevada, was approved as the site for development of the geologic repository for high-level radioactive waste and spent nuclear fuel in the United States. The U.S. Department of Energy has been conducting studies to characterize the site and assess its future performance as a geologic repository. As part of these studies, a program of deep seismic profiling, to depths of 200 m, was conducted along the top of Yucca Mountain to evaluate the shear-wave velocity (V{sub s}) structure … more
Date: March 16, 2004
Creator: Stokoe, K.; Rosenblad, B.; Wong, I.; Bay, J.; Thomas, P. & Silva, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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