Sample records for transitional depth structures

  1. Numerical simulation of the flow over a coastal structure in depth-limited conditions

    E-Print Network [OSTI]

    Ginting, Victor Eralingga

    1998-01-01T23:59:59.000Z

    of detailed measurements of irregular wave transformation in front of the structure in depth-limited conditions. The second data set consists of several test runs to study the irregular wave reflection and runup on the coastal structure in depth...

  2. Accretion disks around Black Holes with Advection and Optical Depth Transition

    E-Print Network [OSTI]

    Yu. V. Artemova; G. S. Bisnovatyi-Kogan; I. V. Igumenshchev; I. D. Novikov

    2004-10-10T23:59:59.000Z

    We consider the effects of advection and radial gradients of pressure and radial drift velocity on the structure of accretion disks around black holes with proper description of optically thick/thin transitions. We concentrated our efforts on the models with large accretion rate. Contrary to disk models neglecting advection, we find that continuous solutions extending from the outer disk regions to the inner edge exist for all accretion rates we have considered. We show that the sonic point moves outward with increasing accretion rate, and that in the innermost disk region advection acts as a heating process that may even dominate over dissipative heating. Despite the importance of advection on it's structure, the disk remains geometrically thin. Global solutions of advective accretion disks, which describe continuously the transition between optically thick outer region and optically thin inner region are constructed and analyzed.

  3. Subsalt Depth Seismic Imaging and Structural Interpretation in Dumre Area, Albania

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Subsalt Depth Seismic Imaging and Structural Interpretation in Dumre Area, Albania A. Jardin1, F Interpretation in Dumre Area, Albania -- The challenge of seismic exploration in fold and thrust belt settings compte plus importante des données géologiques. Abstract -- Subsalt Depth Seismic Imaging and Structural

  4. In Situ TEM Investigation of Congruent Phase Transition and Structural...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    In Situ TEM Investigation of Congruent Phase Transition and Structural Evolution of Nanostructured SiliconCarbon Anode for In Situ TEM Investigation of Congruent Phase Transition...

  5. Structural Transition of Gold Nanoclusters: From the Golden Cage...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transition of Gold Nanoclusters: From the Golden Cage to the Golden Pyramid . Structural Transition of Gold Nanoclusters: From the Golden Cage to the Golden Pyramid . Abstract: How...

  6. Chemisorption-Induced Structural Changes and Transition from...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Chemisorption-Induced Structural Changes and Transition from Chemisorption to Physisorption in Au6(CO)n-(n4-9). Chemisorption-Induced Structural Changes and Transition from...

  7. I -3 Structure interne de la Terre Transition Ol

    E-Print Network [OSTI]

    Grigné, Cécile

    I - 3 Structure interne de la Terre · Transition Ol 410 -- Ol : - pente de Clapeyron "dP dT " 410 positive - transition exothermique · Transition Ol 660 -- Ol : - pente de Clapeyron "dP dT " 660 négative - transition endothermique 410km 660km pérovskite + magnésiowustite olivine olivine olivine C.Grign´e - M2

  8. Structural Transitions from Pyramidal to Fused Planar to Tubular...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transitions from Pyramidal to Fused Planar to Tubular to CoreShell Compact in Gold Clusters: Au-n (n21-25). Structural Transitions from Pyramidal to Fused Planar to Tubular to...

  9. Electronic and structural dynamics in transition metal complexes...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Electronic and structural dynamics in transition metal complexes - recent results from synchrotron and XFEL experiments Wednesday, March 4, 2015 - 3:00pm SLAC, Redtail Hawk...

  10. Complex Faraday depth structure of Active Galactic Nuclei as revealed by broadband radio polarimetry

    E-Print Network [OSTI]

    O'Sullivan, S P; Robishaw, T; Schnitzeler, D H F M; McClure-Griffiths, N M; Feain, I J; Taylor, A R; Gaensler, B M; Landecker, T L; Harvey-Smith, L; Carretti, E

    2012-01-01T23:59:59.000Z

    We present a detailed study of the Faraday depth structure of four bright (> 1 Jy), strongly polarized, unresolved, radio-loud quasars. The Australia Telescope Compact Array (ATCA) was used to observe these sources with 2 GHz of instantaneous bandwidth from 1.1 to 3.1 GHz. This allowed us to spectrally resolve the polarization structure of spatially unresolved radio sources, and by fitting various Faraday rotation models to the data, we conclusively demonstrate that two of the sources cannot be described by a simple rotation measure (RM) component modified by depolarization from a foreground Faraday screen. Our results have important implications for using background extragalactic radio sources as probes of the galactic and intergalactic magneto-ionic media as we show how RM estimations from narrow-bandwidth observations can give erroneous results in the presence of multiple interfering Faraday components. We postulate that the additional RM components arise from polarized structure in the compact inner regio...

  11. Structural Performance of a Full-Depth Precast Concrete Bridge Deck System

    E-Print Network [OSTI]

    Mander, Thomas

    2010-10-12T23:59:59.000Z

    -depth concrete bridge deck overhangs, accelerating the construction of concrete bridge decks, by using full-depth precast prestressed concrete deck panels. Full-depth precast overhang panels in combination with cast-in-place (CIP) reinforced concrete...

  12. Electronic structure and transition energies in polymer-fullerene bulk heterojunctions

    E-Print Network [OSTI]

    2014-01-01T23:59:59.000Z

    Electronic Structure and Transition Energies in Polymer?the HOMO and LUMO energy levels and transition energies haveand charge-transfer transition energies. The interface band

  13. Ion irradiation induced structural and electrical transition in graphene

    SciTech Connect (OSTI)

    Zhou Yangbo; Wang Yifan; Xu Jun; Fu Qiang; Wu Xiaosong; Yu Dapeng [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Liao Zhimin [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, Dublin 2 (Ireland); Duesberg, Georg S. [Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, Dublin 2 (Ireland); School of Chemistry, Trinity College, Dublin 2 (Ireland)

    2010-12-21T23:59:59.000Z

    The relationship between the electrical properties and structure evolution of single layer graphene was studied by gradually introducing the gallium ion irradiation. Raman spectrums show a structural transition from nano-crystalline graphene to amorphous carbon as escalating the degree of disorder of the graphene sample, which is in correspondence with the electrical transition from a Boltzmann diffusion transport to a carrier hopping transport. The results show a controllable method to tune the properties of graphene.

  14. RESEARCH PAPER Phase transition induced formation of hollow structures

    E-Print Network [OSTI]

    Ju, Yiguang

    such as stabilized nano- particles and an oxidation species are usually required to participate in the void formationRESEARCH PAPER Phase transition induced formation of hollow structures in colloidal lanthanide 2009 Ã? Springer Science+Business Media B.V. 2009 Abstract Formation of colloidal hollow structures

  15. Depth-resolved confocal micro-Raman spectroscopy for characterizing GaN-based light emitting diode structures

    SciTech Connect (OSTI)

    Chen, Wei-Liang; Lee, Yu-Yang; Chang, Yu-Ming, E-mail: ymchang@ntu.edu.tw [Center for Condensed Matter Sciences, National Taiwan University, 10617 Taipei, Taiwan (China)] [Center for Condensed Matter Sciences, National Taiwan University, 10617 Taipei, Taiwan (China); Chang, Chiao-Yun; Huang, Huei-Min; Lu, Tien-Chang [Department of Photonics, National Chiao Tung University, 30010 Hsinchu, Taiwan (China)] [Department of Photonics, National Chiao Tung University, 30010 Hsinchu, Taiwan (China)

    2013-11-15T23:59:59.000Z

    In this work, we demonstrate that depth-resolved confocal micro-Raman spectroscopy can be used to characterize the active layer of GaN-based LEDs. By taking the depth compression effect due to refraction index mismatch into account, the axial profiles of Raman peak intensities from the GaN capping layer toward the sapphire substrate can correctly match the LED structural dimension and allow the identification of unique Raman feature originated from the 0.3 ?m thick active layer of the studied LED. The strain variation in different sample depths can also be quantified by measuring the Raman shift of GaN A{sub 1}(LO) and E{sub 2}(high) phonon peaks. The capability of identifying the phonon structure of buried LED active layer and depth-resolving the strain distribution of LED structure makes this technique a potential optical and remote tool for in operando investigation of the electronic and structural properties of nitride-based LEDs.

  16. Structure transitions induced by the Hall term in homogeneous and isotropic magnetohydrodynamic turbulence

    SciTech Connect (OSTI)

    Miura, H., E-mail: miura.hideaki@nifs.ac.jp [Department of Helical Plasma Research, National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Araki, K. [Faculty of Engineering, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005 (Japan)

    2014-07-15T23:59:59.000Z

    Hall effects on local structures in homogeneous, isotropic, and incompressible magnetohydrodynamic turbulence are studied numerically. The transition of vortices from sheet-like to tubular structures induced by the Hall term is found, while the kinetic energy spectrum does not distinguish the two types of structures. It is shown by the use of the sharp low-pass filter that the transition occurs not only in the scales smaller than the ion skin depth but also in a larger scale. The transition is related with the forward energy transfer in the spectral space. Analyses by the use of the sharp low-pass filter show that the nonlinear energy transfer associated with the Hall term is dominated by the forward transfer and relatively local in the wave number space. A projection of the simulation data to a Smagorinsky-type sub-grid-scale model shows that the high wave number component of the Hall term may possibly be replaced by the model effectively.

  17. Structural transitions and elasticity from torque measurements on DNA

    E-Print Network [OSTI]

    Bryant, Zev

    wind-up motors and force­torque converters. Previous investigations of the force­extension behaviour processes such as replication and transcription. Measurements of force and extension on single molecules-induced transitions in DNA structure6,7 , and a theoretical force­torque phase diagram has been proposed that explains

  18. Structural Phase Transition in AuZn Alloys

    SciTech Connect (OSTI)

    Winn,B.L.; Shapiro, S.M.; Lashley, J.C.; Opeil, C.; Ratcliff, W.

    2009-05-03T23:59:59.000Z

    AuxZn1-x alloys undergo a shape memory martensitic transformation whose temperature and nature (continuous or discontinuous) is strongly composition dependent. Neutron diffraction experiments were performed on single crystals of x=50 and 52 to explore the structural changes occurring at the transition temperature. A transverse modulation with wavevector q0=(1/3,1/3,0) develops below the transition temperature, with no observable change in lattice parameter. However, the Bragg peak width shows a broadening suggesting an unresolved rhombohedral distortion similar to what has been observed in NiTi-Fe alloys.

  19. Structural transition and amorphization in compressed ? - Sb 2 O 3

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhao, Zhao; Zeng, Qiaoshi; Zhang, Haijun; Wang, Shibing; Hirai, Shigeto; Zeng, Zhidan; Mao, Wendy L.

    2015-05-01T23:59:59.000Z

    Sb?O?-based materials are of broad interest in materials science and industry. High-pressure study using diamond anvil cells shows promise in obtaining new crystal and electronic structures different from their pristine states. Here, we conducted in situ angle dispersive synchrotron x-ray-diffraction and Raman spectroscopy experiments on ?-Sb?O? up to 50 GPa with neon as the pressure transmitting medium. A first-order structural transition was observed in between 15 and 20 GPa, where the cubic phase I gradually transformed into a layered tetragonal phase II through structural distortion and symmetry breaking. To explain the dramatic changes in sample color and transparency, we performed first-principles calculations to track the evolution of its density of states and electronic structure under pressure. At higher pressure, a sluggish amorphization was observed. Our results highlight the structural connections among the sesquioxides, where the lone electron pair plays an important role in determining the local structures.

  20. Structural phase transitions in BaPrO{sub 3}

    SciTech Connect (OSTI)

    Saines, Paul J. [School of Chemistry, University of Sydney, Sydney, New South Wales 2006 (Australia); Kennedy, Brendan J. [School of Chemistry, University of Sydney, Sydney, New South Wales 2006 (Australia)], E-mail: b.kennedy@chem.usyd.edu.au; Smith, Ronald I. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom)

    2009-04-02T23:59:59.000Z

    The crystal structures adopted by BaPrO{sub 3} at and above ambient temperature have been examined using a combination of synchrotron X-ray and neutron diffraction. BaPrO{sub 3} has been established to undergo a series of phase transitions from Pbnmorthorhombic{yields}Ibmmorthorhombic{yields}R3-bar crhombohedral{yields}Pm3-barm cubic. BaPrO{sub 3} is the second A{sup 2+}B{sup 4+}O{sub 3} perovskite found to adopt rhombohedral symmetry in preference to the I4/mcm tetragonal structure. Analysis of the octahedral tilting through the rhombohedral to cubic phase transition indicates that this transformation is continuous and tricritical in nature. The tricritical behaviour of this transition is likely to be a result of the competition between tetragonal and rhombohedral structures to be the preferred phase, with the rhombohedral symmetry adopted by BaPrO{sub 3} being stabilised by the unusually large B-site cation.

  1. Fine structure transitions of C+ in collisions with H2

    E-Print Network [OSTI]

    Chu, Shih-I; Dalgarno, A.

    1975-01-01T23:59:59.000Z

    ://scitation.aip.org/content/aip/journal/jcp/62/10?ver=pdfcov Published by the AIP Publishing Articles you may be interested in ?doublet substate specific investigation of rotational and fine structure transitions in collisions of OH with H2 and D2 J. Chem. Phys. 95, 5763 (1991); 10... for Astrophysics, Harvard College Observatory and Smithsonian Astrophysical Observatory, Cambridge, Massachusetts 02138 (Received 7 November 1974) Close-coupling calculations are described of the cross sections for the fine-structure excitation of C...

  2. In-depth analysis of CIGS film for solar cells, structural and optical characterization

    E-Print Network [OSTI]

    Slobodskyy, A; ~Ulyanenkova, T; ~Doyle, S; Powalla, M; ~Baumbach, T; ~Lemmer, U

    2010-01-01T23:59:59.000Z

    Space-resolved X-ray diffraction measurements performed on gradient-etched CuIn$_{1-x}$Ga$_x$Se$_2$ (CIGS) solar cells provide information about stress and texture depth profiles in the absorber layer. An important parameter for CIGS layer growth dynamics, the absorber thickness-dependent stress in the molybdenum back contact is analyzed. Texturing of grains and quality of the polycrystalline absorber layer are correlated with the intentional composition gradients (band gap grading). Band gap gradient is determined by space-resolved photoluminescence measurements and correlated with composition and strain profiles.

  3. Cancrinite: Crystal Structure, Phase Transitions, and Dehydration Behavior with Temperature

    SciTech Connect (OSTI)

    Hassan,I.; Antao, S.; Parise, J.

    2006-01-01T23:59:59.000Z

    The structural behavior of a cancrinite, Na{sub 5.96}Ca{sub 1.52}[Al{sub 6}Si{sub 6}O{sub 24}](CO{sub 3}){sub 1.57}{center_dot}1.75H{sub 2}O, was determined by using in situ synchrotron X-ray powder diffraction data [{lambda} = 0.91806(5) {angstrom}] at room pressure and from 25 to 982 {sup o}C. The sample was heated at a rate of about 9.5 {sup o}C/min, and X-ray traces were collected at about 15 {sup o}C intervals. The satellite reflections in cancrinite were lost at about 504 {sup o}C, where a phase transition occurs. All the unit-cell parameters for cancrinite also show a discontinuity at 504 {sup o}C. Initially, the [Ca{center_dot}CO{sub 3}] clusters and their vacancies are ordered in the channels, and this ordering is destroyed on heating to give rise to the phase transition. Cancrinite loses water continuously until about 625 {sup o}C; thereafter an anhydrous cancrinite phase exists. From 25 to 952 {sup o}C, a minimal amount of CO{sub 2} is lost from the structure. Over this temperature range, the average bridging angle, which is an indication of the degree of rotation of the tetrahedra, increases from 143.7(4) to 147.7(5){sup o}. Rotations of the tetrahedra are caused by expansion of the Na1-O2 bond lengths.

  4. Origin of the phase transition in IrTe2: structural modulation and local bonding instability

    SciTech Connect (OSTI)

    Cao, Huibo [ORNL; Chakoumakos, Bryan C [ORNL; Yan, Jiaqiang [ORNL; Zhou, Haidong [ORNL; Custelcean, Radu [ORNL; Mandrus, D. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); McGuire, Michael A [ORNL; Singh, David J [ORNL; Chen, Xin [ORNL; Yang, Hui [University of Tennessee, Knoxville (UTK)

    2013-01-01T23:59:59.000Z

    We used X-ray/neutron diffraction to determine the low temperature (LT) structure of IrTe2. A structural modulation was observed with a wavevector of k =(1/5, 0, 1/5) below Ts285 K, accompanied by a structural transition from a trigonal to a triclinic lattice. We also performed the first principles calculations for high temperature (HT) and LT structures, which elucidate the nature of the phase transition and the LT structure. A local bonding instability associated with the Te 5p states is likely the origin of the structural phase transition in IrTe2.

  5. Structural phase transitions in multipole traps M. Marciante, C. Champenois, A. Calisti, M. Knoop

    E-Print Network [OSTI]

    Boyer, Edmond

    structure. We have studied, by means of molecular dynamics simulations, the structural transition from of the rf electric field which induces a flat pseudo-potential well with a reduced rf-driven micromotion

  6. Conformational Transitions upon Ligand Binding: Holo-Structure Prediction from Apo Conformations

    E-Print Network [OSTI]

    de Groot, Bert

    Conformational Transitions upon Ligand Binding: Holo- Structure Prediction from Apo Conformations Daniel Seeliger, Bert L. de Groot* Computational Biomolecular Dynamics Group, Max design. Hence, if only an unbound (apo) structure is available distinct from the ligand

  7. Structure of liquid transition and rare earth metals S. N. Khanna and F. Cyrot-Lackmann

    E-Print Network [OSTI]

    Boyer, Edmond

    L-45 Structure of liquid transition and rare earth metals S. N. Khanna and F. Cyrot-Lackmann Groupe It is shown that the observed structure factors of transition and rare earth liquid metals can be reaso- nably. The difference is particularly large for V, Ti, and rare earth metals which are precisely the metals where

  8. Influence of the Shape of Crowding Particles on the Structural Transitions in a Polymer

    E-Print Network [OSTI]

    Thirumalai, Devarajan

    Influence of the Shape of Crowding Particles on the Structural Transitions in a Polymer Alexander ABSTRACT: We investigate the structural transitions in a polymer induced by spherical and nonspherical crowding particles over a wide range of conditions. The polymer conformations are specified by the radius

  9. Jamming Transition and Inherent Structures of Hard Spheres and Discs

    E-Print Network [OSTI]

    Misaki Ozawa; Takeshi Kuroiwa; Atsushi Ikeda; Kunimasa Miyazaki

    2012-11-17T23:59:59.000Z

    Recent studies show that volume fractions $\\phiJ$ at the jamming transition of frictionless hard spheres and discs are not uniquely determined but exist over a continuous range. Motivated by this observation, we numerically investigate dependence of $\\phiJ$ on the initial configurations of the parent fluids equilibrated at a fraction $\\phiini$, before compressing to generate a jammed packing. We find that $\\phiJ$ remains constant when $\\phiini$ is small but sharply increases when $\\phiini$ exceeds the dynamic transition point which the mode-coupling theory predicts. We carefully analyze configurational properties of both jammed packings and parent fluids and find that, while all jammed packings remain isostatic, the increase of $\\phiJ$ is accompanied with subtle but distinct changes of (i) local orders, (ii) a static length scale, and (iii) an exponent of the finite size scaling. These results quantitatively support the scenario of the random first order transition theoryof the glass transition.

  10. Structure of ?-Alumina: Toward The Atomic Level Understanding Of Transition Alumina Phases

    SciTech Connect (OSTI)

    Kovarik, Libor; Bowden, Mark E.; Genc, Arda; Szanyi, Janos; Peden, Charles HF; Kwak, Ja Hun

    2014-07-02T23:59:59.000Z

    Transition Al2O3 derived from thermal decomposition of AlOOH Boehmite have complex structures and to a large extent remain poorly understood. Here we report a detailed atomic level analysis of ?Al2O3 for the first time using a combination of Scanning Transmission Electron Microscopy imaging, XRD refinement, and DFT calculations. We show that the structure of ?Al2O3 represents a complex structural intergrowth from several crystallographic variants. The two main crystallographic variants, which are identified as ?1-Al2O3 and ?2?Al2O3, are fully structurally described. In addition, we also derive the energy of formation for ?1 and ?2-Al2O3 and the other relevant transition Al2O3 phases, and show how energetic degeneracy leads to structural disorder and complex intergrowths among several transition Al2O3. The results of the work have important implications for understanding thermodynamic stability and transformation processes in transition alumina.

  11. Microscopic structure of electrowetting-driven transitions on superhydrophobic surfaces

    E-Print Network [OSTI]

    Staicu, A; Mugele, F

    2008-01-01T23:59:59.000Z

    We investigate directly at the microscale the morphology of the electrowetting induced transition between the Cassie-Baxter and Wenzel states for a water droplet on a superhydrophobic surface. Our experiments demonstrate that the transition originates in a very narrow annular region near the macroscopic contact line, which is first invaded by water and causes a thin film of air to be entrapped below. At high applied voltages, a growing fraction of microscopic air-pockets collapse, resulting in a partialWenzel state. Modulations in the intensity of the light reflected from individual micro-menisci clarify that the local contact angles near the filling transition are close to the usual advancing values for contact lines on smooth surfaces.

  12. Measuring the dynamic structure factor of a quantum gas undergoing a structural phase transition

    E-Print Network [OSTI]

    Renate Landig; Ferdinand Brennecke; Rafael Mottl; Tobias Donner; Tilman Esslinger

    2015-03-18T23:59:59.000Z

    The dynamic structure factor is a central quantity describing the physics of quantum many-body systems, capturing structure and collective excitations of a material. In condensed matter, it can be measured via inelastic neutron scattering, which is an energy-resolving probe for the density fluctuations. In ultracold atoms, a similar approach could so far not be applied due to the diluteness of the system. Here, we report on a direct, real-time and non-destructive measurement of the dynamic structure factor of a quantum gas exhibiting cavity-mediated long-range interactions. The technique relies on inelastic scattering of photons, stimulated by the enhanced vacuum field inside a high finesse optical cavity. We extract the density fluctuations, their energy and lifetime while the system undergoes a structural phase transition. We observe an occupation of the relevant quasi-particle mode on the level of a few excitations, and provide a theoretical description of this dissipative quantum many-body system.

  13. PHYSICAL REVIEW B 83, 104106 (2011) Pressure-induced structural transitions in europium to 92 GPa

    E-Print Network [OSTI]

    Schilling, James

    2011-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 83, 104106 (2011) Pressure-induced structural transitions in europium to 92 GPa W-ray diffraction experiments have been carried out on europium metal at ambient temperature to pressures as high

  14. Transition state structures for the hydration of 1,3-dichloroacetone

    E-Print Network [OSTI]

    Cutting, Rebecca Ruth

    1985-01-01T23:59:59.000Z

    TRANSITION STATE STRUCTURES FOR THE HYDRATION OF 3, 3-DI CHLOROACETONE A Thesis by REBECCA RUTH CUTTING Submitted to the Graduate College of Texas ASH University in partial fulfillment of the requirements for the degree of HASTER OF SCIENCE... Hay 1985 Hajor Subject; Chemistry TRANSITION STATE STRUCTURES FOR THE HYDRATION OF 1, 3-DICHLOROACETONE A Thesis by REBECCA RUTH CUTTING Approyed as to style and content by; g o n , ogg ( airman of Corsaittee) enn . arding (Member) J, . a...

  15. Reciprocal space XRD mapping with varied incident angle as a probe of structure variation within surface depth

    SciTech Connect (OSTI)

    Yang, Qiguang [Norfolk State University; Williams, Frances [Norfolk State University; Zhao, Xin [JLAB; Reece, Charles E. [JLAB; Krishnan, Mahadevan [AASC, San Leandro, California

    2013-09-01T23:59:59.000Z

    In this study, we used a differential-depth X-Ray diffraction Reciprocal Spacing Mapping (XRD RSM) technique to investigate the crystal quality of a variety of SRF-relevant Nb film and bulk materials. By choosing different X-ray probing depths, the RSM study successfully revealed evolution the of materials? microstructure after different materials processes, such as energetic condensation or surface polishing. The RSM data clearly measured the materials? crystal quality at different thickness. Through a novel differential-depth RSM technique, this study found: I. for a heteroepitaxy Nb film Nb(100)/MgO(100), the film thickening process, via a cathodic arc-discharge Nb ion deposition, created a near-perfect single crystal Nb on the surface?s top-layer; II. for a mechanically polished single-crystal bulk Nb material, the microstructure on the top surface layer is more disordered than that in-grain.

  16. Concentration-Dependent Structural Transitions of Human Telomeric DNA Sequences

    E-Print Network [OSTI]

    Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada ABSTRACT sequence, dGGGTTA. In the presence of sodium cations, the structure resolved by nuclear magnetic resonance

  17. Structural and thermodynamic properties of Fe{sub 1.12}Te with multiple phase transitions

    SciTech Connect (OSTI)

    Cherian, Dona, E-mail: donacherian@physics.iisc.ernet.in; Elizabeth, Suja [Department of Physics, Indian Institute of Science, Bangalore 560012 (India); Rößler, S.; Koz, C.; Schwarz, U.; Wirth, S. [Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden (Germany); Tsirlin, A. A. [Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden (Germany); National Institute of Chemical Physics and Biophysics, 12618 Tallinn (Estonia)

    2014-03-28T23:59:59.000Z

    The parent compound of iron chalcogenide superconductors, Fe{sub 1+y}Te, with a range of excess Fe concentrations exhibits intriguing structural and magnetic properties. Here, the interplay of magnetic and structural properties of Fe{sub 1.12}Te single crystals have been probed by low-temperature synchrotron X-ray powder diffraction, magnetization, and specific heat measurements. Thermodynamic measurements reveal two distinct phase transitions, considered unique to samples possessing excess Fe content in the range of 0.11?y?0.13. On cooling, an antiferromagnetic transition, T{sub N}?57?K is observed. A closer examination of powder diffraction data suggests that the transition at T{sub N} is not purely magnetic, but accompanied by the commencement of a structural phase transition from tetragonal to orthorhombic symmetry. This is followed by a second prominent first-order structural transition at T{sub S} with T{sub S}structural coupling in this material.

  18. Correlation between oxygen adsorption energy and electronic structure of transition metal macrocyclic complexes

    SciTech Connect (OSTI)

    Liu, Kexi; Lei, Yinkai; Wang, Guofeng, E-mail: guw8@pitt.edu [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States)] [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States)

    2013-11-28T23:59:59.000Z

    Oxygen adsorption energy is directly relevant to the catalytic activity of electrocatalysts for oxygen reduction reaction (ORR). In this study, we established the correlation between the O{sub 2} adsorption energy and the electronic structure of transition metal macrocyclic complexes which exhibit activity for ORR. To this end, we have predicted the molecular and electronic structures of a series of transition metal macrocyclic complexes with planar N{sub 4} chelation, as well as the molecular and electronic structures for the O{sub 2} adsorption on these macrocyclic molecules, using the density functional theory calculation method. We found that the calculated adsorption energy of O{sub 2} on the transition metal macrocyclic complexes was linearly related to the average position (relative to the lowest unoccupied molecular orbital of the macrocyclic complexes) of the non-bonding d orbitals (d{sub z{sup 2}}, d{sub xy}, d{sub xz}, and d{sub yz}) which belong to the central transition metal atom. Importantly, our results suggest that varying the energy level of the non-bonding d orbitals through changing the central transition metal atom and/or peripheral ligand groups could be an effective way to tuning their O{sub 2} adsorption energy for enhancing the ORR activity of transition metal macrocyclic complex catalysts.

  19. Proton inventory investigations of acyl transfer reactions: transition state structures

    E-Print Network [OSTI]

    Patterson, Jacob Floyd

    1978-01-01T23:59:59.000Z

    . The presence of an isotopic label does not alter the electron1c environment of the trans1t1on state, therefore, its structure rema1ns unchanged. Deuterium solvent isotope effects, secondary deuterium isotope effects and a relatively new method, the proton 1.... Other less concentrated buffer solutions were prepared by dilution of the 0. 200 M solutions and adjusting the ionic strength to 0. 20 M with sodium chloride. Solutions at other values of n, the atom fraction of deuterium, were prepared by mixing...

  20. Changes in the Atomic Structure through Glass Transition Observed by X-Ray Scattering

    SciTech Connect (OSTI)

    Egami, Takeshi [ORNL

    2012-01-01T23:59:59.000Z

    The glass transition involves a minor change in the internal energy, and yet the physical and mechanical properties of a glass change dramatically. In order to determine the evolution of the atomic structure through the glass transition, we employed in-situ synchrotron X-ray scattering measurements as a function of temperature on a model material: Zr-Cu-Al metallic glass. We found that the thermal expansion at the atomic level is smaller than the macroscopic thermal expansion, and significantly increases above the glass transition temperature. The observed changes in the pair-distribution function (PDF) are explained in terms of the fluctuations in the local atomic volume and their change through the glass transition.

  1. Resonance structure of strength functions for first-forbidden {beta}{sup +}/EC transitions

    SciTech Connect (OSTI)

    Izosimov, I. N., E-mail: izosimov@jinr.ru; Kalinnikov, V. G.; Solnyshkin, A. A. [Joint Institute for Nuclear Research (Russian Federation)

    2012-11-15T23:59:59.000Z

    Experimental data obtained by measuring the fine structure of the strength function S{sub {beta}}(E) in spherical and deformed nuclei were analyzed. The use of modern nuclear-spectroscopy methods made it possible to reveal the nuclear-deformation-induced splitting of peaks in S{sub {beta}} (E) for transitions of the Gamow-Teller type. For first-forbidden transitions, the resonance nature of S{sub {beta}} (E) was proven experimentally both for spherical and for deformed nuclei. It is shown that, at some values of the excitation energy, the intensity of first-forbidden transitions in nuclei can be commensurate with the intensity of Gamow-Teller transitions.

  2. LEARNING THE DEPTH STRUCTURE OF A MONITORED SCENE J. Renno, D. Greenhill, S. Velastin, G.A. Jones

    E-Print Network [OSTI]

    Jones, Graeme A.

    Digital Imaging Research Centre, Kingston University Penrhyn Road, Kingston upon Thames, Surrey, UK KT1 2, columns, turnstiles, barriers etc or the image boundary itself. These structures induce partial occlusion

  3. Structure and phase transitions into ionic adsorption layers on liquid interfaces

    E-Print Network [OSTI]

    R. Tsekov

    2014-10-25T23:59:59.000Z

    The structure of ionic adsorption layers is studied via a proper thermodynamic treatment of the electrostatic and non-electrostatic interactions between the surfactant ions as well as of the effect of thermodynamic non-locality. The analysis is also applied to phase transitions into the ionic adsorption layer, which interfere further with the oscillatory-diffusive structure of the electric double layer and hydrodynamic stability of squeezing waves in thin liquid films.

  4. Hybrid Car-Parrinello/Molecular Mechanics Modelling of Transition Metal Complexes: Structure, Dynamics and Reactivity

    E-Print Network [OSTI]

    Guidoni, Leonardo

    Hybrid Car-Parrinello/Molecular Mechanics Modelling of Transition Metal Complexes: Structure). We have recently developed a QM/MM extension of a Car-Parrinello scheme [5]. These hybrid Car functional theory embedded in a classical force field description. The power of such a combined Car

  5. STRUCTURE DE BANDES DES CRISTAUX DE TYPE WURTZITE TRANSITIONS OPTIQUES INTRINSQUES DANS LE CdS.

    E-Print Network [OSTI]

    Boyer, Edmond

    825. STRUCTURE DE BANDES DES CRISTAUX DE TYPE WURTZITE TRANSITIONS OPTIQUES INTRINSÈQUES DANS LE Cd Brillouin pour des cristaux de type wurtzite est déduite des considérations de la théorie des groupes. Le Cd d'excitons. Un second article traite le problème de l'exciton dans les cristaux de type wurtzite

  6. Rare-earth transition-metal intermetallics: Structure-bonding-property relationships

    SciTech Connect (OSTI)

    Han, M.K.

    2006-05-06T23:59:59.000Z

    The explorations of rare-earth, transition metal intermetallics have resulted in the synthesis and characterization, and electronic structure investigation, as well as understanding the structure-bonding property relationships. The work has presented the following results: (1) Understanding the relationship between compositions and properties in LaFe{sub 13-x}Si{sub x} system: A detailed structural and theoretical investigation provided the understanding of the role of a third element on stabilizing the structure and controlling the transformation of cubic NaZn{sub 13}-type structures to the tetragonal derivative, as well as the relationship between the structures and properties. (2) Synthesis of new ternary rare-earth iron silicides Re{sub 2-x}Fe{sub 4}Si{sub 14-y} and proposed superstructure: This compound offers complex structural challenges such as fractional occupancies and their ordering in superstructure. (3) Electronic structure calculation of FeSi{sub 2}: This shows that the metal-semiconductor phase transition depends on the structure. The mechanism of band gap opening is described in terms of bonding and structural distortion. This result shows that the electronic structure calculations are an essential tool for understanding the relationship between structure and chemical bonding in these compounds. (4) Synthesis of new ternary rare-earth Zinc aluminides Tb{sub 3}Zn{sub 3.6}Al{sub 7.4}: Partially ordered structure of Tb{sub 3}Zn{sub 3.6}Al{sub 7.4} compound provides new insights into the formation, composition and structure of rare-earth transition-metal intermetallics. Electronic structure calculations attribute the observed composition to optimizing metal-metal bonding in the electronegative (Zn, Al) framework, while the specific ordering is strongly influenced by specific orbital interactions. (5) Synthesis of new structure type of Zn{sub 39}(Cr{sub x}Al{sub 1-x}){sub 81}: These layered structures are similar to icosahedral Mn-Al quasicrystalline compounds. Therefore, this compound may provide new insights into the formation, composition and structure of quasicrystalline materials.

  7. Rare-Earth Transition-Metal Intermetallics: Structure-bonding-Property Relationships

    SciTech Connect (OSTI)

    Mi-Kyung Han

    2006-05-01T23:59:59.000Z

    Our explorations of rare-earth, transition metal intermetallics have resulted in the synthesis and characterization, and electronic structure investigation, as well as understanding the structure-bonding-property relationships. Our work has presented the following results: (1) Understanding the relationship between compositions and properties in LaFe{sub 13-x}Si{sub x} system: A detailed structural and theoretical investigation provided the understanding of the role of a third element on stabilizing the structure and controlling the transformation of cubic NaZn{sub 13}-type structures to the tetragonal derivative, as well as the relationship between the structures and properties. (2) Synthesis of new ternary rare-earth iron silicides RE{sub 2-x}Fe{sub 4}Si{sub 14-y} and proposed superstructure: This compound offers complex structural challenges such as fractional occupancies and their ordering in superstructure. (3) Electronic structure calculation of FeSi{sub 2}: This shows that the metal-semiconductor phase transition depends on the structure. The mechanism of band gap opening is described in terms of bonding and structural distortion. This result shows that the electronic structure calculations are an essential tool for understanding the relationship between structure and chemical bonding in these compounds. (4) Synthesis of new ternary rare-earth Zinc aluminides Tb{sub 3}Zn{sub 3.6}Al{sub 7.4}: Partially ordered structure of Tb{sub 3}Zn{sub 3.6}Al{sub 7.4} compound provides new insights into the formation, composition and structure of rare-earth transition-metal intermetallics. Electronic structure calculations attribute the observed composition to optimizing metal-metal bonding in the electronegative (Zn, Al) framework, while the specific ordering is strongly influenced by specific orbital interactions. (5) Synthesis of new structure type of Zn{sub 39}(Cr{sub x}Al{sub 1-x}){sub 81}: These layered structures are similar to icosahedral Mn-Al quasicrystalline compounds. Therefore, this compound may provide new insights into the formation, composition and structure of quasicrystalline materials.

  8. Earthquake Rupture at Focal Depth, Part I: Structure and Rupture of the Pretorius Fault, TauTona Mine, South Africa

    E-Print Network [OSTI]

    Ze'ev, Reches

    Tona Mine, South Africa V. HEESAKKERS,1,2 S. MURPHY,1,3 and Z. RECHES 1 Abstract--We analyze the structure of the Archaean Pretorius fault in TauTona mine, South Africa, as well as the rupture-zone that recently, South Africa 2011, this volume). Key words: Brittle faulting, fault reactivation, earthquake mechanics

  9. Observation of the structural phase transition in manganite films by magneto-optical imaging.

    SciTech Connect (OSTI)

    Crabtree, G. W.; Lin, Y.; Miller, D. J.; Nikitenko, V. I.; Vlasko-Vlasov, V. K.; Welp, U.

    1999-08-31T23:59:59.000Z

    A high-resolution magneto-optical imaging technique is used to reveal the formation of twins occurring during a martensitic phase transition at {approximately}105K in LCMO films grown on STO substrates. The magnetic contrast arises due to the magneto-elastic tilts of the Mn - magnetic moments in the twins. Different magnetic structures are found in LCMO films grown on MgO, NGO, and LAO substrates showing the importance of the substrate material for the manganite film properties.

  10. A quaternary lead based perovskite structured materials with diffuse phase transition behavior

    SciTech Connect (OSTI)

    Puli, Venkata Sreenivas, E-mail: pvsri123@gmail.com [Department of Physics and Institute for Functional Nano Materials, University of Puerto Rico, San Juan, PR 00936 (United States); Martinez, R.; Kumar, Ashok [Department of Physics and Institute for Functional Nano Materials, University of Puerto Rico, San Juan, PR 00936 (United States)] [Department of Physics and Institute for Functional Nano Materials, University of Puerto Rico, San Juan, PR 00936 (United States); Scott, J.F. [Department of Physics and Institute for Functional Nano Materials, University of Puerto Rico, San Juan, PR 00936 (United States) [Department of Physics and Institute for Functional Nano Materials, University of Puerto Rico, San Juan, PR 00936 (United States); Cavendish Laboratory, Dept. Physics, University of Cambridge, Cambridge CB0 3HE (United Kingdom); Katiyar, Ram S., E-mail: rkatiyar@uprrp.edu [Department of Physics and Institute for Functional Nano Materials, University of Puerto Rico, San Juan, PR 00936 (United States)

    2011-12-15T23:59:59.000Z

    Graphical abstract: (a) Curie-Weiss plot for the inverse of the relative dielectric permittivity and (b) log (1/{epsilon} - 1/{epsilon}{sub m}) as function of log (T - T{sub m}) for ceramics at 1 kHz. Highlights: Black-Right-Pointing-Pointer Retaining phase pure structure with quaternary complex stoichiometric compositions. Black-Right-Pointing-Pointer P-E loops with good saturation polarization (P{sub s} {approx} 30.7 {mu}C/cm{sup 2}). Black-Right-Pointing-Pointer Diffused relaxor phase transition behavior with {gamma} estimated is {approx}1.65. -- Abstract: A lead based quaternary compound composed of 0.25(PbZr{sub 0.52}Ti{sub 0.48}O{sub 3}) + 0.25(PbFe{sub 0.5}Ta{sub 0.5}O{sub 3}) + 0.25 (PbF{sub 0.67}W{sub 0.33}O{sub 3}) + 0.25(PbFe{sub 0.5}Nb{sub 0.5}O{sub 3}) - (PZT-PFT-PFW-PFN) was synthesized by conventional solid-state reaction techniques. It showed moderate high dielectric constant, low dielectric loss, and two diffuse phase transitions, one below the room temperature {approx}261 K and other above {approx}410 K. X-ray diffraction (XRD) patterns revealed a tetragonal crystal structure at room temperature where as scanning electron micrograph (SEM) indicates inhomogeneous surface with an average grain size of 500 nm-3 {mu}m. Well saturated ferroelectric hysteresis loops with good saturation polarization (spontaneous polarization, P{sub s} {approx} 30.68 {mu}C/cm{sup 2}) were observed. Temperature-dependent ac conductivity displayed low conductivity with kink in spectra near the phase transition. In continuing search for developing new ferroelectric materials, in the present study we report stoichiometric compositions of complex perovskite ceramic materials: (PZT-PFT-PFW-PFN) with diffuse phase transition behavior. The crystal structure, dielectric properties, and ferroelectric properties were characterized by XRD, SEM, dielectric spectroscopy, and polarization. 1/{epsilon} versus (T) plots revealed diffuse relaxor phase transition (DPT) behavior. The compositional variation on the phase transition temperature, dielectric constant, and ferroelectric to paraelectric phase transitions are discussed.

  11. Structural phase transition in CuFe{sub 2}O{sub 4} spinel

    SciTech Connect (OSTI)

    Balagurov, A. M., E-mail: bala@nf.jinr.ru; Bobrikov, I. A.; Maschenko, M. S.; Sangaa, D.; Simkin, V. G. [Joint Institute for Nuclear Research (Russian Federation)] [Joint Institute for Nuclear Research (Russian Federation)

    2013-09-15T23:59:59.000Z

    A structural transition with a reduction in symmetry of the high temperature cubic phase (sp. gr. Fd3m) to the tetragonal phase (sp. gr. I4{sub 1}/amd) and the appearance of a ferrimagnetic structure occur in CuFe{sub 2}O{sub 4} copper ferrite at T Almost-Equal-To 440 Degree-Sign C. It is established by an experiment on a high-resolution neutron diffractometer that the temperature at which long-range magnetic order occurs is higher than that of tetragonal phase formation. When cooling CuFe{sub 2}O{sub 4} spinel from 500 Degree-Sign C, the equilibrium coexistence of both phases is observed in a fairly wide temperature range ({approx}40 Degree-Sign C). The composition studied is a completely inverse spinel in the cubic phase, and in the tetragonal phase the inversion parameter does not exceed few percent (x = 0.06 {+-} 0.04). At the same time, the phase formed upon cooling has a classical value of tetragonal distortion ({gamma} Almost-Equal-To 1.06). The character of temperature changes in the structural parameters during the transition from cubic to tetragonal phase indicates that this transition is based on the Jahn-Teller distortion of (Cu,Fe)O{sub 6} octahedra rather than the mutual migration of copper and iron atoms.

  12. Structural-chemical modeling of transition of coals to the plastic state

    SciTech Connect (OSTI)

    A.M. Gyul'maliev; S.G. Gagarin [FGUP Institute for Fossil Fuels, Moscow (Russian Federation)

    2007-02-15T23:59:59.000Z

    The structural-chemical simulation of the formation of plastic state during the thermal treatment (pyrolysis, coking) of coals is based on allowance for intermolecular interactions in the organic matter. The feasibility of transition of coals to the plastic state is determined by the ratio between the onset plastic state (softening) and runaway degradation temperatures, values that depend on the petrographic composition and the degree of metamorphism of coals and the distribution of structural and chemical characteristics of organic matter. 33 refs., 8 figs., 2 tabs.

  13. Synthesis and structural, magnetic, thermal, and transport properties of several transition metal oxides and aresnides

    SciTech Connect (OSTI)

    Das, Supriyo

    2010-05-16T23:59:59.000Z

    Oxide compounds containing the transition metal vanadium (V) have attracted a lot of attention in the field of condensed matter physics owing to their exhibition of interesting properties including metal-insulator transitons, structural transitions, ferromagnetic and antiferromagnetic orderings, and heavy fermion behavior. Binary vanadium oxides V{sub n}O{sub 2n-1} where 2 {le} n {le} 9 have triclinic structures and exhibit metal-insulator and antiferromagnetic transitions. The only exception is V{sub 7}O{sub 13} which remains metallic down to 4 K. The ternary vanadium oxide LiV{sub 2}O{sub 4} has the normal spinel structure, is metallic, does not undergo magnetic ordering and exhibits heavy fermion behavior below 10 K. CaV{sub 2}O{sub 4} has an orthorhombic structure with the vanadium spins forming zigzag chains and has been suggested to be a model system to study the gapless chiral phase. These provide great motivation for further investigation of some known vanadium compounds as well as to explore new vanadium compounds in search of new physics. This thesis consists, in part, of experimental studies involving sample preparation and magnetic, transport, thermal, and x-ray measurements on some strongly correlated eletron systems containing the transition metal vanadium. The compounds studied are LiV{sub 2}O{sub 4}, YV{sub 4}O{sub 8}, and YbV{sub 4}O{sub 8}. The recent discovery of superconductivity in RFeAsO{sub 1-x}F{sub x} (R = La, Ce, Pr, Gd, Tb, Dy, Sm, and Nd), and AFe{sub 2}As{sub 2} (A = Ba, Sr, Ca, and Eu) doped with K, Na, or Cs at the A site with relatively high T{sub c} has sparked tremendous activities in the condensed matter physics community and a renewed interest in the area of superconductivity as occurred following the discovery of the layered cuprate high T{sub c} superconductors in 1986. To discover more superconductors with hopefully higher T{sub c}'s, it is extremely important to investigate compounds having crystal structures related to the compounds showing high T{sub c} superconductivity. Along with the vanadium oxide compounds described before, this thesis describes our investigations of magnetic, structural, thermal and transport properties of EuPd{sub 2}Sb{sub 2} single crystals which have a crystal structure closely related to the AFe{sub 2}As{sub 2} compounds and also a study of the reaction kinetics of the formation of LaFeAsO{sub 1-x}F{sub x}.

  14. Electronic Structure and Properties of Transition Metal-Benzene Ravindra Pandey, Bijan K. Rao,*, Purusottam Jena, and Miguel Alvarez Blanco

    E-Print Network [OSTI]

    Pandey, Ravi

    Electronic Structure and Properties of Transition Metal-Benzene Complexes Ravindra Pandey, Bijan Kd transition metal atoms (M) interacting with benzene molecules (Bz) is carried out using density. The variation of the metal-benzene distances, dissociation energies, ionization potentials, electron affinities

  15. SnTe field effect transistors and the anomalous electrical response of structural phase transition

    SciTech Connect (OSTI)

    Li, Haitao, E-mail: haitao.li@nist.gov; Zhu, Hao; Yuan, Hui; Li, Qiliang, E-mail: qli6@gmu.edu [Department of Electrical and Computer Engineering, George Mason University, Fairfax, Virginia 22030 (United States); Semiconductor and Dimensional Metrology Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); You, Lin; Kopanski, Joseph J. [Department of Electrical and Computer Engineering, George Mason University, Fairfax, Virginia 22030 (United States); Richter, Curt A. [Semiconductor and Dimensional Metrology Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Zhao, Erhai [School of Physics, Astronomy, and Computational Sciences, George Mason University, Fairfax, Virginia 22030 (United States)

    2014-07-07T23:59:59.000Z

    SnTe is a conventional thermoelectric material and has been newly found to be a topological crystalline insulator. In this work, back-gate SnTe field-effect transistors have been fabricated and fully characterized. The devices exhibit n-type transistor behaviors with excellent current-voltage characteristics and large on/off ratio (>10{sup 6}). The device threshold voltage, conductance, mobility, and subthreshold swing have been studied and compared at different temperatures. It is found that the subthreshold swings as a function of temperature have an apparent response to the SnTe phase transition between cubic and rhombohedral structures at 110?K. The abnormal and rapid increase in subthreshold swing around the phase transition temperature may be due to the soft phonon/structure change which causes the large increase in SnTe dielectric constant. Such an interesting and remarkable electrical response to phase transition at different temperatures makes the small SnTe transistor attractive for various electronic devices.

  16. Structure and dynamics of colloidal depletion gels: coincidence of transitions and heterogeneity

    E-Print Network [OSTI]

    C. J. Dibble; M. Kogan; M. J. Solomon

    2006-06-06T23:59:59.000Z

    Transitions in structural heterogeneity of colloidal depletion gels formed through short-range attractive interactions are correlated with their dynamical arrest. The system is a density and refractive index matched suspension of 0.20 volume fraction poly(methyl methacyrlate) colloids with the non-adsorbing depletant polystyrene added at a size ratio of depletant to colloid of 0.043. As the strength of the short-range attractive interaction is increased, clusters become increasingly structurally heterogeneous, as characterized by number-density fluctuations, and dynamically immobilized, as characterized by the single-particle mean-squared displacement. The number of free colloids in the suspension also progressively declines. As an immobile cluster to gel transition is traversed, structural heterogeneity abruptly decreases. Simultaneously, the mean single-particle dynamics saturates at a localization length on the order of the short-range attractive potential range. Both immobile cluster and gel regimes show dynamical heterogeneity. Non-Gaussian distributions of single particle displacements reveal enhanced populations of dynamical trajectories localized on two different length scales. Similar dependencies of number density fluctuations, free particle number and dynamical length scales on the order of the range of short-range attraction suggests a collective structural origin of dynamic heterogeneity in colloidal gels.

  17. Electronic Structure of Transition Metal-Cysteine Complexes From X-Ray Absorption Spectroscopy

    SciTech Connect (OSTI)

    Leung, B.O.; Jalilehvand, F.; Szilagyi, R.K.

    2009-05-19T23:59:59.000Z

    The electronic structures of Hg{sup II}, Ni{sup II}, Cr{sup III}, and Mo{sup V} complexes with cysteine were investigated by sulfur K-edge X-ray absorption near-edge structure (XANES) spectroscopy and density functional theory. The covalency in the metal-sulfur bond was determined by analyzing the intensities of the electric-dipole allowed pre-edge features appearing in the XANES spectra below the ionization threshold. Because of the well-defined structures of the selected cysteine complexes, the current work provides a reference set for further sulfur K-edge XAS studies of bioinorganic active sites with transition metal-sulfur bonds from cysteine residues as well as more complex coordination compounds with thiolate ligands.

  18. Core-shell structures in single flexible-semiflexible block copolymers: Finding the free energy minimum for the folding transition

    E-Print Network [OSTI]

    Natsuhiko Yoshinaga; Kenichi Yoshikawa

    2007-06-11T23:59:59.000Z

    We investigate the folding transition of a single diblock copolymer consisting of a semiflexible and a flexible block. We obtain a {\\it Saturn-shaped} core-shell conformation in the folded state, in which the flexible block forms a core and the semiflexible block wraps around it. We demonstrate two distinctive features of the core-shell structures: (i) The kinetics of the folding transition in the copolymer are significantly more efficient than those of a semiflexible homopolymer. (ii) The core-shell structure does not depend on the transition pathway.

  19. Families of solutions to the generalized Ginzburg-Landau equation and structural transitions between them

    SciTech Connect (OSTI)

    Ovchinnikov, Yu. N., E-mail: ovc@itp.ac.ru [Max-Planck Institute for Physics of Complex Systems (Germany)

    2013-09-15T23:59:59.000Z

    Solutions to the generalized Ginzburg-Landau equations for superconductors are obtained for a Ginzburg-Landau parameter {kappa} close to unity. The families of solutions with arbitrary number n of flux quanta in a unit cell are analyzed. It is shown that under certain conditions, a cascade of phase transitions between different structures in a magnetic field appears near T{sub c}. Algebraic equations are derived for determining the boundaries of coexistence of different phases on the (T, H{sub 0}) plane.

  20. Polarization-dependent all-optical modulator with ultra-high modulation depth based on a stereo graphene-microfiber structure

    E-Print Network [OSTI]

    Xu, Fei; Zheng, Bi-cai; Shao, Guang-hao; Ge, Shi-jun; Lu, Yan-qing

    2015-01-01T23:59:59.000Z

    We report an in-line polarization-dependent all-optical fiber modulator based on a stereo graphene-microfiber structure (GMF) by utilizing the lab-on-rod technique. Owing to the unique spring-like geometry, an ultra-long GMF interaction length can be achieved, and an ultra-high modulation depth (MD) of ~7.5 dB and a high modulation efficiency (ME) of ~0.2 dB/mW were demonstrated for one polarization state. The MD and ME are more than one order larger than those of other graphene-waveguide hybrid all-optical modulators. By further optimizing the transferring and cleaning process, the modulator can quickly switch between transparent and opaque states for both the two polarization states with a maximized MD of tens of decibels. This modulator is compatible with current fiber-optic communication systems and may be applied in the near future to meet the impending need for ultrafast optical signal processing.

  1. Free-energy functional for freezing transitions: Hard sphere systems freezing into crystalline and amorphous structures

    E-Print Network [OSTI]

    Swarn Lata Singh; Atul S. Bharadwaj; Yashwant Singh

    2011-01-31T23:59:59.000Z

    A free-energy functional that contains both the symmetry conserved and symmetry broken parts of the direct pair correlation function has been used to investigate the freezing of a system of hard spheres into crystalline and amorphous structures. The freezing parameters for fluid-crystal transition have been found to be in very good agreement with the results found from simulations. We considered amorphous structures found from the molecular dynamics simulations at packing fractions $\\eta$ lower than the glass close packing fraction $\\eta_{J}$ and investigated their stability compared to that of a homogeneous fluid. The existence of free-energy minimum corresponding to a density distribution of overlapping Gaussians centered around an amorphous lattice depicts the deeply supercooled state with a heterogeneous density profile.

  2. Prediction of pressure induced structural phase transitions and internal mode frequency changes in solid N/sub 2/+

    SciTech Connect (OSTI)

    Etters, R.D.; Kobashi, K.; Chandrasekharan, V.

    1983-01-01T23:59:59.000Z

    A rhombohedral distortion of the Pm3n structure is introduced which shows that a low temperature phase transition occurs from P4/sup 2//mnm into the R3c calcite structure at P approx. = 19.2 kbar with a volume change of 0.125 cm/sup 3//mole. This transition agrees with recent Raman scattering measurements. Another transition from R3c into R3m is predicted at P approx. = 67.5 kbar, with a volume change of 0.1 cm/sup 3//mole. The pressure dependence of the intramolecular mode frequencies for the R3c structure is in reasonably good agreement with the two main branches observed experimentally.

  3. High-temperature, structural disorder, phase transitions, and piezoelectric properties of GaPO{sub 4}

    SciTech Connect (OSTI)

    Haines, J.; Cambon, O.; Prudhomme, N.; Fraysse, G.; Keen, D. A.; Chapon, L. C.; Tucker, M. G. [Laboratoire de Physico-Chimie de la Matiere Condensee, UMR CNRS 5617, Universite Montpellier II, Place Eugene Bataillon, cc003, 34095 Montpellier cedex 5 (France); Department of Physics, Oxford University, Clarendon Laboratory, Parks Road, Oxford OX1 3PU (United Kingdom); and ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ (United Kingdom)

    2006-01-01T23:59:59.000Z

    Gallium orthophosphate was studied at high temperature up to 1303 K by total neutron scattering and 1173 K by piezoelectric measurements. Rietveld refinements at 1223 K confirm the stability of the structural distortion in the {alpha}-quartz-type phase with an average tilt angle {delta}=18.8 deg. at this temperature. In contrast, reverse Monte Carlo (RMC) refinements of total neutron scattering data indicate that, whereas the degree of structural disorder initially slowly varies over a very large temperature interval in the {alpha}-quartz-type phase, an increase in disorder is observed beginning above 1023 K. Piezoelectric measurements indicate that the quality factor (Q) of GaPO{sub 4} resonators remains stable up to this temperature above which the piezoelectric properties of the material degrade. This degradation can be correlated to the increase in structural disorder. RMC refinements indicate that the high-temperature {beta}-cristobalite-type phase at 1303 K is characterized by significant thermally induced disorder with oxygen atom density forming a continuous ring around the vector joining neighboring gallium and phosphorous atoms. Gallium phosphate may be expected to retain its piezoelectric properties up to within 200 K of the phase transition temperature and as a consequence be used in applications at temperatures slightly above 1000 K.

  4. Synthesis, structural characterization and high pressure phase transitions of monolithium hydronium sulfate

    SciTech Connect (OSTI)

    Banerjee, Debasis, E-mail: debasis.banerjee@stonybrook.edu [Department of Chemistry, Stony Brook University, Stony Brook 11794-3400 (United States); Plonka, Anna M. [Department of Geosciences, Stony Brook University, Stony Brook 11794-2100 (United States); Kim, Sun Jin [Nano-Materials Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650 (Korea, Republic of); Xu Wenqian [Department of Geosciences, Stony Brook University, Stony Brook 11794-2100 (United States); Parise, John B. [Department of Chemistry, Stony Brook University, Stony Brook 11794-3400 (United States); Mineral Physics Institute, Stony Brook University, Stony Brook, NY 11790-2100 (United States)

    2013-01-15T23:59:59.000Z

    A three dimensional lithium hydronium sulfate LiSO{sub 4}{center_dot}H{sub 3}O [1], [space group Pna2{sub 1}a=8.7785(12) A, b=9.1297(12) A, c=5.2799(7) A, V=423.16(10) A{sup 3}] was synthesized via solvothermal methods using 1,5-naphthalenedisulfonic acid (1,5-NSA) as the source of sulfate ions. The structure of [1], determined by single crystal X-ray diffraction techniques, consists of corner sharing LiO{sub 4} and SO{sub 4} tetrahedra, forming an anionic 3-D open framework that is charge balanced by hydronium ions positioned within channels running along [001] and forming strong H-bonding with the framework oxygen atoms. Compound [1] undergoes two reversible phase transitions, involving reorientation of SO{sub 4}{sup 2-} ions at pressures of approximately 2.5 and 5 GPa at room temperature, as evident from characteristic discontinuous frequency drops in the {nu}{sub 1} mode of the Raman spectra. Additionally, compound [1] forms dense {beta}-lithium sulfate at 300 Degree-Sign C, as evident from temperature dependent powder XRD and combined reversible TGA-DSC experiments. - Graphical abstract: Left: View of corner-shared LiO{sub 4} and SO{sub 4} tetrahedra along [001] direction with hydronium ions situated in the channels. Right: (a) Photograph of the loaded DAC (b) Ambient pressure Raman spectrum of compound [1] (c) Evolution of the {nu}{sub 1} mode with the increasing and decreasing pressure indicating transitions to high-pressure phases at {approx}2.5 (red curves) and {approx}5 GPa (blue curves) and at {approx}3.5 GPa upon decompression. Highlights: Black-Right-Pointing-Pointer A 3-D lithium hydronium sulfate is synthesized by solvothermal methods. Black-Right-Pointing-Pointer Two high pressure phase transition occurs due to rotation of sulfate groups. Black-Right-Pointing-Pointer The framework undergoes a high temperature structural transformation, to form {beta}-Li{sub 2}SO{sub 4} phase.

  5. The influence of transition metal solutes on dislocation core structure and values of Peierls stress and barrier in tungsten.

    SciTech Connect (OSTI)

    Samolyuk, German D [ORNL; Stoller, Roger E [ORNL; Osetskiy, Yury N [ORNL

    2013-01-01T23:59:59.000Z

    Several transition metals were examined to evaluate their potential for improving the ductility of tungsten. We investigate the dislocation core structure, Peierls stress and barrier of $1/2\\langle111\\rangle$ screw dislocations in binary tungsten-transition metal alloys (W$_{1-x}$TM$_{x}$) based on first principles electronic structure calculations. The periodic quadrupole approach was applied to model the structure of $1/2\\langle111\\rangle$ dislocation. The alloying with transition metals was modeled using the virtual crystal approximation. In order to verify the applicability of this approach, the equilibrium lattice parameter and elastic constants were calculated for tungsten alloyed with the set of transition metals. Reasonable agreement was obtained between results using the virtual crystal approximation and those using both a conventional super-cell approach and existing experimental data. Increasing the concentration of a transition metal from the VIIIA group leads to reduction of the $C^\\prime$ elastic constant and increase of elastic anisotropy A=$C_{44}/C^\\prime$. It was demonstrated that alloying W with a group VIIIA transition metal changes the structure of the dislocation core from symmetric to asymmetric, similar to results obtained for W$_{1-x}$Re$_{x}$ alloys in the earlier work of Romaner {\\it et al} (Phys. Rev. Lett. 104, 195503 (2010)). Following the core symmetry change, the values of the Peierls stress and barrier are reduced. This combination of two effects could lead to increased ductility in a tungsten-based alloy\\comments. Our results demonstrate that similar effects could be achieved with any of the transition metals from the VIIIA group.

  6. Computational Studies of the Electronic Structures and Mechanisms of Late Transition Metal Systems 

    E-Print Network [OSTI]

    Pitts, Amanda

    2013-08-27T23:59:59.000Z

    Late transition metal species are heavily studied because of their diverse applications in industrial, synthetic, and biological processes. Transition metals can alter the thermodynamic aspects of a reaction by creating ...

  7. Thermoelectric material including a multiple transition metal-doped type I clathrate crystal structure

    DOE Patents [OSTI]

    Yang, Jihui (Lakeshore, CA); Shi, Xun (Troy, MI); Bai, Shengqiang (Shanghai, CN); Zhang, Wenqing (Shanghai, CN); Chen, Lidong (Shanghai, CN); Yang, Jiong (Shanghai, CN)

    2012-01-17T23:59:59.000Z

    A thermoelectric material includes a multiple transition metal-doped type I clathrate crystal structure having the formula A.sub.8TM.sub.y.sub.1.sup.1TM.sub.y.sub.2.sup.2 . . . TM.sub.y.sub.n.sup.nM.sub.zX.sub.46-y.sub.1.sub.-y.sub.2.sub.- . . . -y.sub.n.sub.-z. In the formula, A is selected from the group consisting of barium, strontium, and europium; X is selected from the group consisting of silicon, germanium, and tin; M is selected from the group consisting of aluminum, gallium, and indium; TM.sup.1, TM.sup.2, and TM.sup.n are independently selected from the group consisting of 3d, 4d, and 5d transition metals; and y.sub.1, y.sub.2, y.sub.n and Z are actual compositions of TM.sup.1, TM.sup.2, TM.sup.n, and M, respectively. The actual compositions are based upon nominal compositions derived from the following equation: z=8q.sub.A-|.DELTA.q.sub.1|y.sub.1-|.DELTA.q.sub.2|y.sub.2- . . . -|.DELTA.q.sub.n|y.sub.n, wherein q.sub.A is a charge state of A, and wherein .DELTA.q.sub.1, .DELTA.q.sub.2, .DELTA.q.sub.n are, respectively, the nominal charge state of the first, second, and n-th TM.

  8. Persistence of transition state structure in chemical reactions driven by fields oscillating in time

    E-Print Network [OSTI]

    Galen T. Craven; Thomas Bartsch; Rigoberto Hernandez

    2014-04-29T23:59:59.000Z

    Chemical reactions subjected to time-varying external forces cannot generally be described through a fixed bottleneck near the transition state barrier or dividing surface. A naive dividing surface attached to the instantaneous, but moving, barrier top also fails to be recrossing-free. We construct a moving dividing surface in phase space over a transition state trajectory. This surface is recrossing-free for both Hamiltonian and dissipative dynamics. This is confirmed even for strongly anharmonic barriers using simulation. The power of transition state theory is thereby applicable to chemical reactions and other activated processes even when the bottlenecks are time-dependent and move across space.

  9. Evaluation of the Structure of Levee Transitions on Wave Runup and Overtopping by Physical Modeling

    E-Print Network [OSTI]

    Oaks, Drake Benjamin

    2011-08-08T23:59:59.000Z

    traditional overtopping techniques have predicted. The runup values and floodwall wave heights tend to show potential problematic areas and mimic the variation of overtopping along the levee transition. Under the design conditions tested, extreme overtopping...

  10. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20T23:59:59.000Z

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  11. Structural response in FeCl2 (iron chloride) to pressure-induced electro-magnetic transitions

    SciTech Connect (OSTI)

    Taylor, R D [Los Alamos National Laboratory; Rozenberg, G Kh [TEL AVIV UNIV; Pasternak, M P [TEL AVIV UNIV; Gorodetsky, P [TEL AVIV UNIV; Xu, W M [TEL AVIV UNIV; Dubrovinsky, L S [UNIV OF BAYREUTH; Le Bihan, T L [FRANCE

    2009-01-01T23:59:59.000Z

    High pressure (HP) synchrotron x-ray diffraction studies were carried out in FeCl{sub 2} together with resistivity (R) studies, at various temperatures and pressures to 65 GPa using diamond anvil cells. This work follows a previous HP {sup 57}Fe Mossbauer study in which two pressure-induced (PI) electronic transitions were found interpreted as: (i) quenching of the orbital-term contribution to the hyperfine field concurring with a tilting of the magnetic moment by 55 degrees and (ii) collapse of the magnetism concurring with a sharp decrease of the isomer shift (IS). The R(P,T) studies affirm that the cause the collapse of the magnetism is a PI p-d correlation breakdown, leading to an insulator-metal transition at {approx}45 GPa and is not due to a spi-Ir,crossover (S=2 {yields} S=0). The structure response to the pressure evolution of the two electronic phase transitions starting at low pressures (LP), through an intermediate phase (IP) 30-57 GPa, and culminating in a high-pressure phase (HP), P >32 GPa, can clearly be quantified. The IP-HP phases coexist through the 32-57 GPa range in which the HP abundance increases monotonically at the expense of the IP phase. At the LP-IP interface no volume change is detected, yet the c-axis increases and the a-axis shrinks by 0.21 Angstroms and 0.13 Angstroms, respectively. The fit of the equation of state of the combined LP-IP phases yields a bulk modulus K{sub 0} = 35.3(1.8) GPa. The intralayer CI-CI distances increases, but no change is observed in Fe-CI bond-length nor are there substantial changes in the interlayer spacing. The pressure-induced electronic IP-HP transition leads to a first-order structural phase transition characterized by a decrease in Fe-CI bond length and an abrupt drop in V(P) by {approx}3.5% accompanying the correlation breakdown. In this transition no symmetry change is detected,and the XRD data could be satisfactorily fitted with the CdI{sub 2} structure. The bulk modulus of the HP phase is practically the same as that of the LP-IP phases suggesting negligible changes in the phonon density of state.

  12. JOURNAL DE PHYSIQUE Colloque C4, suppliment au no 5, Tome 35, Mai 1974,page C4-329 ELECTRONIC STRUCTURE OF LIQUID TRANSITION

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    STRUCTURE OF LIQUID TRANSITION AND RARE-EARTH METALS AND THEIR ALLOYS (*) G. BUSCH, H.-J. GUNTHERODT, H. U and rare earth metals and their alloys is reviewed. The results are compared with recent theories taking-free-electron moael [I]. This model may not be valid in liquid transition and rare-earth metals and their alloys due

  13. Structural transitions of ternary imide Li{sub 2}Mg(NH){sub 2} for hydrogen storage

    SciTech Connect (OSTI)

    Liang, C. [College of Materials Science and Engineering, Zhejiang University of Technology, Hangzhou 310014 (China); State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province and Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Gao, M. X.; Pan, H. G., E-mail: hgpan@zju.edu.cn; Liu, Y. F. [State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province and Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China)

    2014-08-25T23:59:59.000Z

    Phase transitions and energetic properties of Li{sub 2}Mg(NH){sub 2} with different crystal structures are investigated by experiments and first-principles calculations. The Li{sub 2}Mg(NH){sub 2} with the primitive cubic and orthorhombic structure is obtained by dynamically dehydrogenating a Mg(NH{sub 2}){sub 2}-2LiH mixture up to 280?°C under an initial vacuum and 9.0?bars H{sub 2}, respectively. It is found that the obtained orthorhombic Li{sub 2}Mg(NH){sub 2} is converted to a primitive cubic structure as the dehydrogenation temperature is further increased to 400?°C or performed by a 36?h of high-energetic ball milling. Moreover, the primitive cubic phase can be converted to an orthorhombic phase after heating at 280?°C under 9.0?bars H{sub 2} for 1?h. Thermodynamic calculations show that the orthorhombic phase is the ground state structure of Li{sub 2}Mg(NH){sub 2}. The mechanism for phase transitions of Li{sub 2}Mg(NH){sub 2} is also discussed from the angle of energy.

  14. Structures and transitions in solid O/sub 2/ to 13 GPa at 298 K by x-ray diffraction

    SciTech Connect (OSTI)

    Olinger, B.; Mills, R.L.; Roof R.B. Jr.

    1984-12-01T23:59:59.000Z

    The structures and phase transitions in solid O/sub 2/ were studied at 298 K from 6 to 13 GPa using powder x-ray diffraction in an anvil cell. Pressures were determined from the compression of in situ NaF. X-ray photographs at various pressures showed patterns from five different phases of O/sub 2/, two of which were previously unreported. Values of the bulk modulus and volume were derived up to 11 GPa where transition to epsilon-O/sub 2/ occurs. A compromise fit to all available data indicates that epsilon-O/sub 2/ may be an orthorhombic distortion of delta-O/sub 2/.

  15. FINAL TECHNICAL REPORT Synthetic, Structural and Mechanistic Investigations of Olefin Polymerization Catalyzed by Early Transition Metal Compounds

    SciTech Connect (OSTI)

    Bercaw, John E. [California Institute of Technology

    2014-05-23T23:59:59.000Z

    The goal of this project is to develop new catalysts and provide understanding of ligand effects on catalyst composition in order to guide development of superior catalyst systems for polymerization of olefins. Our group is designing and synthesizing new “LX2”,“pincer” type ligands and complexing early transition metals to afford precatalysts. In a collaboration with Hans Brintzinger from the University of Konstanz, we are also examining the structures of the components of catalyst systems obtained from reaction of zirconocene dichlorides with aluminum alkyls and aluminum hydrides. Such systems are currently used commercially to produce polyolefins, but the nature of the active and dormant species as well as the mechanisms of their interconversions are not understood. New information on catalyst design and performance may lead to new types of polymers and/or new chemical transformations between hydrocarbons and transition metal centers, ultimately contributing to the development of catalytic reactions for the production of fuels, commodity and polymeric materials.

  16. Structural and Morphological Transitions in Gold Nanorods: A Computer Simulation Study

    E-Print Network [OSTI]

    Dellago, Christoph

    to the particles by the laser is selected to be under the threshold for complete melting, intermediate products are exposed to low-energy laser pulses, they can undergo shape transitions at temperatures below melting of gold nanorods with various aspect ratios. In these experiments, laser pulses are used to selectively

  17. Structural and magnetic properties of transition metal substituted BaFe{sub 2}As{sub 2} compounds studied by x-ray and neutron scattering

    SciTech Connect (OSTI)

    Kim, Min Gyu [Ames Laboratory

    2012-08-28T23:59:59.000Z

    The purpose of my dissertation is to understand the structural and magnetic properties of the newly discovered FeAs-based superconductors and the interconnection between superconductivity, antiferromagnetism, and structure. X-ray and neutron scattering techniques are powerful tools to directly observe the structure and magnetism in this system. I used both xray and neutron scattering techniques on di#11;erent transition substituted BaFe2As2 compounds in order to investigate the substitution dependence of structural and magnetic transitions and try to understand the connections between them.

  18. Structural study and phase transition investigation in a simple synthesis of porous architected-ZnO nanopowder

    SciTech Connect (OSTI)

    Shang, C.; Barnabé, A., E-mail: barnabe@chimie.ups-tlse.fr

    2013-12-15T23:59:59.000Z

    In this work, zinc oxide powder with a rectangular-shaped porous architecture, made of numerous spherical nanometric particles, was obtained. A simple precipitation/decomposition procedure was used comprising a zinc oxalate intermediate, obtained from zinc sulfate and oxalic acid without any additives. Detailed studies on zinc oxalate dehydration, decomposition and zinc oxide formation, were carried out using in-situ temperature X-ray diffraction and thermogravimetric analysis. During the investigation, the temperature dependence of particle sizes, lattice parameters and crystal structures of ZnC{sub 2}O{sub 4}·2H{sub 2}O, ZnC{sub 2}O{sub 4} and ZnO nanopowders were analyzed from room temperature to 450 °C. Structural transitions were also discussed. The structure and morphology of the as-prepared ZnO nanopowder were investigated by electron microscopy and compared to the crystalline rectangular shape of ZnC{sub 2}O{sub 4}·2H{sub 2}O. The calcination temperature, counter ion and precipitate agent were found to be related to the product's shape and diameter. Spherical ZnO nanoparticles with diameters of less than 20 nm and a maximum specific surface of 53 m{sup 2}/g were obtained using this method. Highlights: • ZnO nanopowders with porous architecture were synthesized by a simple method. • Spherical ZnO nanoparticles confined in submicronic rectangular shape are obtained. • Crystal structures are determined temperature in-situ XRD up to 450 °C. • Structural transitions were analyzed.

  19. Structure formation upon reactive direct current magnetron sputtering of transition metal oxide films

    SciTech Connect (OSTI)

    Ngaruiya, J.M.; Kappertz, O.; Mohamed, S.H.; Wuttig, M. [I. Physikalisches Institut der RWTH Aachen, D-52056 Aachen, Germany and Jomo Kenyatta University of Agriculture and Technology, Box 62000 Nairobi (Kenya); I. Physikalisches Institut der RWTH Aachen, D-52056 Aachen (Germany)

    2004-08-02T23:59:59.000Z

    A comparative study of reactive direct current magnetron sputtering for different transition metal oxides reveals crystalline films at room temperature for group 4 and amorphous films for groups 5 and 6. This observation cannot be explained by the known growth laws and is attributed to the impact of energetic particles, originating from the oxidized target, on the growing film. This scenario is supported by measured target characteristics, the evolution of deposition stress of the films, and the observed backsputtering.

  20. Transitions in eigenvalue and wavefunction structure in (1+2)-body random matrix ensembles with spin

    SciTech Connect (OSTI)

    Vyas, Manan [Physical Research Laboratory, Ahmedabad 380 009 (India); Kota, V. K. B. [Physical Research Laboratory, Ahmedabad 380 009 (India); Department of Physics, Laurentian University, Sudbury, Ontario, P3E 2C6 (Canada); Chavda, N. D. [Applied Physics Department, Faculty of Technology and Engineering, M.S. University of Baroda, Vadodara 390 001 (India)

    2010-03-15T23:59:59.000Z

    Finite interacting Fermi systems with a mean-field and a chaos generating two-body interaction are modeled by one plus two-body embedded Gaussian orthogonal ensemble of random matrices with spin degree of freedom [called EGOE(1+2)-s]. Numerical calculations are used to demonstrate that, as lambda, the strength of the interaction (measured in the units of the average spacing of the single-particle levels defining the mean-field), increases, generically there is Poisson to GOE transition in level fluctuations, Breit-Wigner to Gaussian transition in strength functions (also called local density of states) and also a duality region where information entropy will be the same in both the mean-field and interaction defined basis. Spin dependence of the transition points lambda{sub c}, lambda{sub F}, and lambda{sub d}, respectively, is described using the propagator for the spectral variances and the formula for the propagator is derived. We further establish that the duality region corresponds to a region of thermalization. For this purpose we compared the single-particle entropy defined by the occupancies of the single-particle orbitals with thermodynamic entropy and information entropy for various lambda values and they are very close to each other at lambda=lambda{sub d}.

  1. IN-DEPTH REPORT: Environmental

    E-Print Network [OSTI]

    in local policy debates about fracking. This In-depth Report from Science for Environment Policy explores

  2. Soft matter in hard confinement: phase transition thermodynamics, structure, texture, diffusion and flow in nanoporous media - topical review

    E-Print Network [OSTI]

    Huber, Patrick

    2015-01-01T23:59:59.000Z

    Spatial confinement in nanoporous media affects the structure, thermodynamics and mobility of molecular soft matter often markedly. This article reviews thermodynamic equilibrium phenomena, such as physisorption, capillary condensation, crystallisation, self-diffusion, and structural phase transitions as well as selected aspects of the emerging field of spatially confined, non-equilibrium physics, i.e. the rheology of liquids, capillarity-driven flow phenomena, and imbibition front broadening in nanoporous materials. The observations in the nanoscale systems are related to the corresponding bulk phenomenologies. The complexity of the confined molecular species is varied from simple building blocks, like noble gas atoms, normal alkanes and alcohols to liquid crystals, polymers, ionic liquids, proteins and water. Mostly, experiments with mesoporous solids of alumina, carbon, gold, silica, and silicon having pore diameters ranging from a few up to 50 nanometers are presented. The observed peculiarities of nanopo...

  3. Shock-Induced Structural Phase Transition, Plasticity, and Brittle Cracks in Aluminum Nitride Ceramic

    E-Print Network [OSTI]

    Southern California, University of

    into an elastic wave and a slower SPT wave that transforms the wurtzite structure into the rocksalt phase into the wurtzite phase. Nanovoids coalesce into mode I cracks while dislocations give rise to kink bands and mode. Before impact, the crystal- line structure of the target material is wurtzite. The z axis, parallel

  4. Structural phase transitions on the nanoscale: The crucial pattern in the phase-change materials Ge2Sb2Te5 and GeTe

    E-Print Network [OSTI]

    Structural phase transitions on the nanoscale: The crucial pattern in the phase-change materials Ge2Sb2Te5 and GeTe J. Akola1,2 and R. O. Jones1 1Institut für Festkörperforschung, Forschungszentrum to characterize the amorphous structure of the prototype materials Ge2Sb2Te5 and GeTe. In both, there is long

  5. A microsecond time resolved x-ray absorption near edge structure synchrotron study of phase transitions in Fe undergoing ramp heating at high pressure

    SciTech Connect (OSTI)

    Marini, C.; Mathon, O.; Pascarelli, S. [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, BP220, 38043 Grenoble Cedex (France); Occelli, F.; Torchio, R.; Recoules, V.; Loubeyre, P. [CEA, Bruyeres le Chatel, 91297 Arpajon Cedex (France)

    2014-03-07T23:59:59.000Z

    We report a microsecond time-resolved x-ray absorption near edge structure study using synchrotron radiation to dynamically detect structural phase transitions in Fe undergoing rapid heating along a quasi-isochoric path. Within a few ms, we observed two structural phase transitions, which transform the ambient bcc phase of Fe into the fcc phase, and then into the liquid phase. This example illustrates the opportunities offered by energy dispersive x-ray absorption spectroscopy in the study of matter under extreme dynamic conditions. Advanced simulations are compared to these data.

  6. Hydrothermal syntheses, structures and magnetic properties of two transition metal coordination polymers with a square

    E-Print Network [OSTI]

    Gao, Song

    ; Square grid structure; 1,4-Naphthalenedicarb- oxylic acid 1. Introduction In recent years, great.1. Measurements Elemental analyses were performed with an Elemen- tar Vario EL analyzer. The IR spectrum

  7. Influence of step morphology on the structural phase transition of the ?-Al{sub 2}O{sub 3}(0001) surface

    SciTech Connect (OSTI)

    Tosaka, Aki, E-mail: a-tosaka@yokohama-cu.ac.jp; Kitamura, Tatsuya; Sugiyama, Takuhiro; Shigeta, Yukichi [Nanosystem Science, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027 (Japan); Koyama, Koji [Namiki Precision Jewel Co., Ltd., 3-8-22 Shinden, Adachi-ku, Tokyo 123-8511 (Japan)

    2014-06-02T23:59:59.000Z

    The structural phase transition from the 1?×?1 to the ?31?×??31?±?R9° structure of two types of ?-Al{sub 2}O{sub 3}(0001) surfaces has been investigated using reflection high-energy electron diffraction. One of the ?-Al{sub 2}O{sub 3}(0001) surfaces was composed of regularly arranged monolayer steps (M-surface), and the other surface was composed of multiples of bilayer high steps (B-surface). The surface transition from the 1?×?1 to the ?31?×??31?±?R9° structure starts at 1200?°C on the M-surface, but the transition occurs at 1600?°C on the B-surface. We discuss the difference in the stability of these surfaces at high temperature from the viewpoint of the stoichiometry near the step edge and conclude that the B-surface is more stable than the M-surface.

  8. Soft matter in hard confinement: phase transition thermodynamics, structure, texture, diffusion and flow in nanoporous media - topical review

    E-Print Network [OSTI]

    Patrick Huber

    2015-02-16T23:59:59.000Z

    Spatial confinement in nanoporous media affects the structure, thermodynamics and mobility of molecular soft matter often markedly. This article reviews thermodynamic equilibrium phenomena, such as physisorption, capillary condensation, crystallisation, self-diffusion, and structural phase transitions as well as selected aspects of the emerging field of spatially confined, non-equilibrium physics, i.e. the rheology of liquids, capillarity-driven flow phenomena, and imbibition front broadening in nanoporous materials. The observations in the nanoscale systems are related to the corresponding bulk phenomenologies. The complexity of the confined molecular species is varied from simple building blocks, like noble gas atoms, normal alkanes and alcohols to liquid crystals, polymers, ionic liquids, proteins and water. Mostly, experiments with mesoporous solids of alumina, carbon, gold, silica, and silicon having pore diameters ranging from a few up to 50 nanometers are presented. The observed peculiarities of nanopore-confined condensed matter are also discussed with regard to applications. A particular emphasis is put on texture formation upon crystallisation in nanoporous media, a topic both of high fundamental interest and of increasing nanotechnological importance, e.g., for the synthesis of organic/inorganic hybrid materials by melt infiltration, the usage of nanoporous solids in crystal nucleation or in template-assisted electrochemical deposition of nano structures.

  9. Structural phase transition of alkane molecules in nanotube composites Chenyu Wei*

    E-Print Network [OSTI]

    Wei, Chenyu

    interests but also is impor- tant for the applications of nanocomposites or hybrid materials. In this study in this study would be useful and important for the understanding of structural phases in hybrid polymer struc- tures, which sizes are comparable to polymer or biological molecules. Their composites or hybrid

  10. SURFACE TENSION AND DEFORMATIONS OF MEMBRANE STRUCTURES : RELATION TO TWO-DIMENSIONAL PHASE TRANSITIONS

    E-Print Network [OSTI]

    Boyer, Edmond

    1099 SURFACE TENSION AND DEFORMATIONS OF MEMBRANE STRUCTURES : RELATION TO TWO-DIMENSIONAL PHASE les molécules sont en contact avec un réservoir. Dans le premier cas, la tension de surface est nulle tension de surface finie et les fluctuations sont très réduites. Ce résultat est en accord avec des

  11. Femtosecond soft x-ray spectroscopy of solvated transition metal complexes: Deciphering the interplay of electronic and structural dynamics

    SciTech Connect (OSTI)

    Huse, Nils; Cho, Hana; Hong, Kiryong; Jamula, Lindsey; de Groot, Frank M. F.; Kim, Tae Kyu; McCusker, James K.; Schoenlein, Robert W.

    2011-03-09T23:59:59.000Z

    We present the first implementation of femtosecond soft X-ray spectroscopy as an ultrafast direct probe of the excited-state valence orbitals in solution-phase molecules. This method is applied to photoinduced spin crossover of [Fe(tren(py)3)]2+, where the ultrafast spinstate conversion of the metal ion, initiated by metal-to-ligand charge-transfer excitation, is directly measured using the intrinsic spin-state selectivity of the soft X-ray L-edge transitions. Our results provide important experimental data concerning the mechanism of ultrafast spin-state conversion and subsequent electronic and structural dynamics, highlighting the potential of this technique to study ultrafast phenomena in the solution phase.

  12. A study of structural transition in nanocrystalline titania thin films by X-ray diffraction Rietveld method

    SciTech Connect (OSTI)

    Murugesan, S. [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)] [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Padhy, N. [Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)] [Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Kuppusami, P., E-mail: pk@igcar.gov.in [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Mudali, U. Kamachi [Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)] [Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Mohandas, E. [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)] [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)

    2010-12-15T23:59:59.000Z

    Structural and microstructural analyses of nanocrystalline titania thin films prepared by pulsed laser deposition have been carried out. At lower oxygen partial pressures ({<=}10{sup -4} mbar), rutile films were formed, whereas at 1.2 x 10{sup -3} mbar of oxygen partial pressure, the thin films contained both rutile and anatase phases. At 0.04 and 0.05 mbar of oxygen partial pressure, the film was purely anatase. Addition of oxygen has also shown a profound influence on the surface morphology of the as deposited titania films. Modified Rietveld method has been used to determine crystallite size, root mean square strain and fractional coordinates of oxygen of the anatase films. The influence of crystallite size and strain on the rutile to anatase phase transition is investigated.

  13. Fine-structure calculations of energy levels, oscillator strengths, and transition probabilities for sulfur-like iron, Fe XI

    SciTech Connect (OSTI)

    Abou El-Maaref, A., E-mail: aahmh@hotmail.com [Physics Department, Faculty of Science, Al-Azhar University, Assuit (Egypt); Ahmad, Mahmoud [Physics Department, Faculty of Science, Al-Azhar University, Assuit (Egypt); Allam, S.H. [Laboratory of Lasers and New Materials, Physics Department, Faculty of Science, Cairo University, Giza (Egypt)

    2014-05-15T23:59:59.000Z

    Energy levels, oscillator strengths, and transition probabilities for transitions among the 14 LS states belonging to configurations of sulfur-like iron, Fe XI, have been calculated. These states are represented by configuration interaction wavefunctions and have configurations 3s{sup 2}3p{sup 4}, 3s3p{sup 5}, 3s{sup 2}3p{sup 3}3d, 3s{sup 2}3p{sup 3}4s, 3s{sup 2}3p{sup 3}4p, and 3s{sup 2}3p{sup 3}4d, which give rise to 123 fine-structure energy levels. Extensive configuration interaction calculations using the CIV3 code have been performed. To assess the importance of relativistic effects, the intermediate coupling scheme by means of the Breit–Pauli Hamiltonian terms, such as the one-body mass correction and Darwin term, and spin–orbit, spin–other-orbit, and spin–spin corrections, are incorporated within the code. These incorporations adjusted the energy levels, therefore the calculated values are close to the available experimental data. Comparisons between the present calculated energy levels as well as oscillator strengths and both experimental and theoretical data have been performed. Our results show good agreement with earlier works, and they might be useful in thermonuclear fusion research and astrophysical applications. -- Highlights: •Accurate atomic data of iron ions are needed for identification of solar corona. •Extensive configuration interaction wavefunctions including 123 fine-structure levels have been calculated. •The relativistic effects by means of the Breit–Pauli Hamiltonian terms are incorporated. •This incorporation adjusts the energy levels, therefore the calculated values are close to experimental values.

  14. alluvial basins in-depth: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of structures requires more accurate design methods. An important variable in the fire performance of timber structures is the in-depth temperature distribution, ......

  15. Structure and magnetism of transition-metal implanted dilute magnetic semiconductors

    E-Print Network [OSTI]

    Pereira, Lino; Temst, K; Araújo, JP; Wahl, U

    The discovery of a dilute magnetic semiconductor (DMS) in which ferromagnetism is carrier-mediated and persists above room temperature is a critical step towards the development of semiconductor-based spintronics. Among the many types of DMS materials which have been investigated, the current research interest can be narrowed down to two main classes of materials: (1) narrow-gap III-V semiconductors, mostly GaAs and InAs, doped with Mn; (2) wide-gap oxides and nitrides doped with 3d transition metals, mostly Mn- and Co-doped ZnO and Mn-doped GaN. With a number of interesting functionalities deriving from the carrier-mediated ferromagnetism and demonstrated in various proof-of-concept devices, Mn-doped GaAs has become, among DMS materials, one of the best candidates for technological application. However, despite major developments over the last 15 years, the maximum Curie temperature (185 K) remains well below room temperature. On the other hand, wide-gap DMS materials appear to exhibit ferromagnetic behavior...

  16. Dual mechanisms of Laramide structural growth: the Bighorn uplift-Powder River basin transition

    SciTech Connect (OSTI)

    Jenkins, C.D. Jr.; Lisenbee, A.L.

    1986-08-01T23:59:59.000Z

    The Bighorn uplift margin from Buffalo to Dayton, Wyoming, consists of a northern monoclinal domain and a southern fault-segmented domain. The Precambrian basement and overlying Paleozoic-Mesozoic strata have been rotated and folded in the monocline, producing a structural relief of 17,000 ft. Range-directed thrusts, formed by compression in the synclinal hinge of the monocline, are responsible for several second-order structures. The monocline may be transported eastward above a Rich-model thrust in the basement. The southern domain displays up to 20,000 ft of structural relief and consists of contiguous fault-bounded blocks with eastern margins 2 to 9 mi long. The largest and northernmost fault-bounded block, the Precambrian-cored Piney block, was transported eastward along a west-dipping reverse fault. Drilling indicates the fault overlies a vertical Cretaceous-Tertiary section underlain by nearly flat strata below the top of the Cretaceous Parkman Sandstone. Wells drilled through the Precambrian-cored Clear Creek thrust block west of Buffalo suggest a similar structural development. Reverse faulting in the southern domain occurred at a late stage, cutting through the synclinal flexure of the monocline, or occurred contemporaneously with the formation of the monocline to the north. Paleocene and Eocene syntectonic conglomerates underlie and front the range-bounding faults and exhibit basal angular unconformities. An arcuate band of conglomerates on the east side of Mowry basin implies the existence of other thrusts beneath Tertiary strata in the topographic basin, a conclusion reinforced by seismic data.

  17. Electronic Structure of Transition Metal Clusters and Actinide Complexes and Their Reactivity

    SciTech Connect (OSTI)

    Balasubramanian, K

    2008-10-06T23:59:59.000Z

    Our research in this area since October 2007 has resulted in seven completed publications and more papers of the completed work are in progress. Our work during this period principally focused on actinide complexes with secondary emphasis on spectroscopic properties and electronic structure of metal complexes. As the publications are available online with all of the details of the results, tables and figures, we are providing here only a brief summary of major highlights, in each of the categories.

  18. Structures and Reactivity of Transition-Metal Compounds Featuring Metal-Ligand Multiple Bonds

    E-Print Network [OSTI]

    Xu, Zhenggang

    2014-07-25T23:59:59.000Z

    isomers of product 2a-f. .................................................................. 89 Figure 34. The rearrangement between 2_iso6 and 2_iso3. ............................................. 92 Figure 35. The solvated ?G (kcal/mol) diagram... iso3 and iso6 for 2a-f (kcal/mol). ................ 91 Table 17. Results of energies differencesa between 2c_iso6 and 2c_iso3. ...................... 92 xv Table 18. Selected structural parameters of 2a from computations and experiments. (Bond...

  19. Couples Magnetic and Structural Transitions in High-Purity Dy and Gd5SbxGe4-x

    SciTech Connect (OSTI)

    Alexander S. Chernyshov

    2006-08-09T23:59:59.000Z

    Magnetic materials exhibiting magnetic phase transitions simultaneously with structural rearrangements of their crystal lattices hold a promise for numerous applications including magnetic refrigeration, magnetomechanical devices and sensors. We undertook a detailed study of a single crystal of dysprosium metal, which is a classical example of a system where magnetic and crystallographic sublattices can be either coupled or decoupled from one another. Magnetocaloric effect, magnetization, ac magnetic susceptibility, and heat capacity of high purity single crystals of dysprosium have been investigated over broad temperature and magnetic field intervals with the magnetic field vector parallel to either the a- or c-axes of the crystal. Notable differences in the behavior of the physical properties when compared to Dy samples studied in the past have been observed between 110 K and 125 K, and between 178 K and {approx}210 K. A plausible mechanism based on the formation of antiferromagnetic clusters in the impure Dy has been suggested in order to explain the reduction of the magnetocaloric effect in the vicinity of the Neel point. Experimental and theoretical investigations of the influence of commensurability effects on the magnetic phase diagram and the value of the magnetocaloric effect have been conducted. The presence of newly found anomalies in the physical properties has been considered as evidence of previously unreported states of Dy. The refined magnetic phase diagram of dysprosium with the magnetic field vector parallel to the a-axis of a crystal has been constructed and discussed. The magnetic and crystallographic properties of Gd{sub 5}Sb{sub x}Ge{sub 4-x} pseudo-binary system were studied by x-ray diffraction (at room temperature), heat capacity, ac-magnetic susceptibility, and magnetization in the temperature interval 5-320 K in magnetic fields up to 100 kOe. The magnetic properties of three composition (x = 0.5, 1,2) were examined in detail. The Gd{sub 5}Sb{sub 2}Ge{sub 2} compound that adopts Tm{sub 5}Sb{sub 2}Si{sub 2}-type of structure (space group is Cmca), shows a second order FM-PM transition at 200 K, whereas Gd{sub 5}Sb{sub x}Ge{sub 4-x} compounds for x = 0.5 and x = 1 (Sm{sub 5}Ge{sub 4}-type of structure, space group is Pnma) exhibit first order phase transformations at 45 K and 37 K, respectively.

  20. Pressure-induced structural transition of double-walled carbon nanotubes Surface Physics Laboratory and Department of Physics, Fudan University, Shanghai 200433, China

    E-Print Network [OSTI]

    Gong, Xingao

    Pressure-induced structural transition of double-walled carbon nanotubes X. Ye Surface Physics Laboratory and Department of Physics, Fudan University, Shanghai 200433, China D. Y. Sun Department of Physics, East China Normal University, Shanghai 200062, China X. G. Gong Surface Physics Laboratory

  1. Selecting the suitable dopants: electronic structures of transition metal and rare earth doped thermoelectric sodium cobaltate

    E-Print Network [OSTI]

    Assadi, M H N; Yu, A B

    2012-01-01T23:59:59.000Z

    Engineered Na0.75CoO2 is considered a prime candidate to achieve high efficiency thermoelectric systems to regenerate electricity from waste heat. In this work, three elements with outmost electronic configurations, (1) an open d shell (Ni), (2) a closed d shell (Zn), and (3) an half fill f shell (Eu) with a maximum unpaired electrons, were selected to outline the dopants' effects on electronic and crystallographic structures of Na0.75CoO2. Systematic ab initio density functional calculations showed that the formation energy of these dopants was found to be lowest when residing on sodium layer and ranked as -1.1 eV, 0.44 eV and 3.44 eV for Eu, Ni and Zn respectively. Furthermore Ni was also found to be stable when substituting Co ion. As these results show great harmony with existing experimental data, they provide new insights into the fundamental principle of dopant selection for manipulating the physical properties in the development of high performance sodium cobaltate based thermoelectric materials.

  2. Formation depths of Fraunhofer lines

    E-Print Network [OSTI]

    Gurtovenko, E A

    2015-01-01T23:59:59.000Z

    We have summed up our investigations performed in 1970--1993. The main task of this paper is clearly to show processes of formation of spectral lines as well as their distinction by validity and by location. For 503 photospheric lines of various chemical elements in the wavelength range 300--1000 nm we list in Table the average formation depths of the line depression and the line emission for the line centre and on the half-width of the line, the average formation depths of the continuum emission as well as the effective widths of the layer of the line depression formation. Dependence of average depths of line depression formation on excitation potential, equivalent widths, and central line depth are demonstrated by iron lines.

  3. Depth dependent dynamics in the hydration shell of a protein

    E-Print Network [OSTI]

    J. Servantie; C. Atilgan; A. R. Atilgan

    2010-07-31T23:59:59.000Z

    We study the dynamics of hydration water/protein association in folded proteins, using lysozyme and myoglobin as examples. Extensive molecular dynamics simulations are performed to identify underlying mechanisms of the dynamical transition that corresponds to the onset of amplified atomic fluctuations in proteins. The number of water molecules within a cutoff distance of each residue scales linearly with protein depth index and is not affected by the local dynamics of the backbone. Keeping track of the water molecules within the cutoff sphere, we observe an effective residence time, scaling inversely with depth index at physiological temperatures while the diffusive escape is highly reduced below the transition. A depth independent orientational memory loss is obtained for the average dipole vector of the water molecules within the sphere when the protein is functional. While below the transition temperature, the solvent is in a glassy state, acting as a solid crust around the protein, inhibiting any large scale conformational fluctuations. At the transition, most of the hydration shell unfreezes and water molecules collectively make the protein more flexible.

  4. Global transition zone tomography Jeroen Ritsema1

    E-Print Network [OSTI]

    Ritsema, Jeroen

    Global transition zone tomography Jeroen Ritsema1 and Hendrik Jan van Heijst Seismological on accurate models of seismic velocity variation in the upper mantle transition zone (400­1000 km depth. Such data provide new global transition zone constraints. We combined more than a million measurements

  5. Pressure induced phase transition and pressure dependence of crystal structure in low {(alpha)} and Ca/A1-doped cristobalite.

    SciTech Connect (OSTI)

    Parise, D. J. B.; Yeganeh-Haeri, A.; Weidner, D. J.; Jorgensen, J. D.; Saltzberg, M. A.; Materials Science Division; CHiPR; State Univ. of New York at Stony Brook; CHiPr; E.I. DuPont Co.

    1994-01-01T23:59:59.000Z

    The phase stability and atomic-level compression mechanisms for both SiO{sub 2} cristobalite, and for cristobalite partially stabilized by Ca/Al doping (Ca{sub x/2} Si{sub 2-x}Al{sub x}O{sub 4}), have been investigated. A phase transition to a lower symmetry phase, observed with in situ high-pressure energy-dispersive x-ray diffraction, occurs at about 1.2 GPa. Structure models of the low-pressure phase were obtained by Rietveld analysis of neutron powder-diffraction data from powdered samples contained in a gas pressure apparatus. These data were collected at pressures up to 0.6 GPa and at 298 and 60 K. The results suggest collapse of the corner-connected framework from rotations of the rigid SiO{sub 4} tetrahedra at high pressures and low temperatures as the dominant mechanism for the densification of both materials. Compared to pure SiO{sub 2} cristobalite at the same pressure and temperature, the Ca/Al-doped material has a larger unit-cell volume. It also has a larger Si-O-Si bending angle and a more expanded framework as evidenced by the smaller rotations of the rigid SiO{sub 4} tetrahedra. The rate of change of these parameters as a function of pressure and temperature is the same for both pure and Ca/Al-doped cristobalite. These observations are consistent with Ca occupying positions within the cavities formed by the (Si, Al)-O framework and bracing it against collapse.

  6. Structural evolution across the insulator-metal transition in oxygen-deficient BaTiO3-? studied using neutron total scattering and Rietveld analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jeong, I.-K.; Lee, Seunghun; Jeong, Se-Young; Won, C. J.; Hur, N.; Llobet, A.

    2011-08-01T23:59:59.000Z

    Oxygen-deficient BaTiO3-? exhibits an insulator-metal transition with increasing ?. We performed neutron total scattering measurements to study structural evolution across an insulator-metal transition in BaTiO3-?. Despite its significant impact on resistivity, slight oxygen reduction (?=0.09) caused only a small disturbance on the local doublet splitting of Ti-O bond. This finding implies that local polarization is well preserved under marginal electric conduction. In the highly oxygen-deficient metallic state (?=0.25), however, doublet splitting of the Ti-O bond became smeared. The smearing of the local Ti-O doublet is complemented with long-range structural analysis and demonstrates that the metallic conduction in the highly oxygen-reducedmore »BaTiO3-? is due to the appearance of nonferroelectric cubic lattice.« less

  7. Structural evolution across the insulator-metal transition in oxygen-deficient BaTiO3-? studied using neutron total scattering and Rietveld analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jeong, I.-K.; Lee, Seunghun; Jeong, Se-Young; Won, C. J.; Hur, N.; Llobet, A.

    2011-08-01T23:59:59.000Z

    Oxygen-deficient BaTiO3-? exhibits an insulator-metal transition with increasing ?. We performed neutron total scattering measurements to study structural evolution across an insulator-metal transition in BaTiO3-?. Despite its significant impact on resistivity, slight oxygen reduction (?=0.09) caused only a small disturbance on the local doublet splitting of Ti-O bond. This finding implies that local polarization is well preserved under marginal electric conduction. In the highly oxygen-deficient metallic state (?=0.25), however, doublet splitting of the Ti-O bond became smeared. The smearing of the local Ti-O doublet is complemented with long-range structural analysis and demonstrates that the metallic conduction in the highly oxygen-reduced BaTiO3-? is due to the appearance of nonferroelectric cubic lattice.

  8. Rotating drum variable depth sampler

    DOE Patents [OSTI]

    Nance, Thomas A. (Aiken, SC); Steeper, Timothy J. (Trenton, SC)

    2008-07-01T23:59:59.000Z

    A sampling device for collecting depth-specific samples in silt, sludge and granular media has three chambers separated by a pair of iris valves. Rotation of the middle chamber closes the valves and isolates a sample in a middle chamber.

  9. Structural phase transition and magnetism in hexagonal SrMnO{sub 3} by magnetization measurements and by electron, x-ray, and neutron diffraction studies

    SciTech Connect (OSTI)

    Daoud-Aladine, A.; Chapon, L. C.; Knight, K. S. [ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Martin, C. [Laboratoire CRISMAT-UMR, 6508 ENSI CAEN, 6, Marechal Juin, 14050 Caen (France); ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Hervieu, M. [Laboratoire CRISMAT-UMR, 6508 ENSI CAEN, 6, Marechal Juin, 14050 Caen (France); Brunelli, M. [European Synchrotron Radiation Facility, BP220, F-38043 Grenoble Cedex (France); Radaelli, P. G. [ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

    2007-03-01T23:59:59.000Z

    The structural and magnetic properties of the hexagonal four-layer form of SrMnO{sub 3} have been investigated by combining magnetization measurements, electron diffraction, and high-resolution synchrotron x-ray and neutron powder diffraction. Below 350 K, there is subtle structural phase transition from hexagonal symmetry (space group P6{sub 3}/mmc) to orthorhombic symmetry (space group C222{sub 1}) where the hexagonal metric is preserved. The second-order phase transition involves a slight tilting of the corner-sharing Mn{sub 2}O{sub 9} units composed of two face-sharing MnO{sub 6} octahedra and the associated displacement of Sr{sup 2+} cations. The phase transition is described in terms of symmetry-adapted displacement modes of the high symmetry phase. Upon further cooling, long range magnetic order with propagation vector k=(0,0,0) sets in below 300 K. The antiferromagnetic structure, analyzed using representation theory, shows a considerably reduced magnetic moment indicating the crucial role played by direct exchange between Mn centers of the Mn{sub 2}O{sub 9} units.

  10. Structural transition from L1{sub 0} phase to A1 phase in FePt films caused by ion irradiation

    SciTech Connect (OSTI)

    Hasegawa, T.; Li, G.Q.; Pei, W.; Saito, H.; Ishio, S.; Taguchi, K.; Yamakawa, K.; Honda, N.; Ouchi, K.; Aoyama, T.; Sato, I. [Department of Materials Science and Engineering, Akita University, 1-1 Tegatagakuen-mati, Akita 010-8502 (Japan); Akita Research Institute of Advanced Technology, 4-21 Sanuki, Akita 010-1623 (Japan); TDK Corporation, 462-1 Otai, Saku-shi, Nagano 385-0009 (Japan)

    2006-03-01T23:59:59.000Z

    The effect of ion irradiation (B{sup +},Cr{sup +},Ga{sup +}, and Nb{sup +}) on the crystalline structure and magnetic properties of L1{sub 0} (face-centered tetragonal structure) FePt films was investigated. Irradiating with Cr{sup +}, Ga{sup +}, and Nb{sup +} ions of less than 1 at. % (1.6x10{sup 15} ions/cm{sup 2}) dose yielded an almost ideal structural transition from the L1{sub 0} to A1 (face-centered cubic structure) phase withoutdamage to the surface of the film. This structural transition was accompanied by a change in magnetic properties from a hard magnet with a coercivity H{sub c} of {approx}7 kOe to a soft magnet with H{sub c}<1 kOe. A two-dimensional pattern composed of hard magnetic L1{sub 0} and soft magnetic A1 phases was fabricated by using a focused Ga{sup +} ion beam.

  11. Pressure Effect on the Structural Transition and Suppression of the High-Spin State in the Triple-Layer T'-La?Ni?O?

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Cheng, J.-G.; Zhou, J.-S.; Goodenough, J. B.; Zhou, H. D.; Matsubayashi, K.; Uwatoko, Y.; Kong, P. P.; Jin, C. Q.; Yang, W. G.; Shen, G. Y.

    2012-06-01T23:59:59.000Z

    We report a comprehensive high-pressure study on the triple-layer T'-La?Ni?O? with a suite of experimental probes, including structure determination, magnetic, and transport properties up to 50 GPa. Consistent with a recent ab inito calculation, application of hydrostatic pressure suppresses an insulator-metal spin-state transition at Pc?6 GPa. However, a low-spin metallic phase does not emerge after the high-spin state is suppressed to the lowest temperature. For P>20 GPa, the ambient T' structure transforms gradually to a T†-type structure, which involves a structural reconstruction from fluorite La–O?–La blocks under low pressures to rock-salt LaO-LaO blocks under high pressures. Absence of the metallic phase under pressure has been discussed in terms of local displacements of O²? ions in the fluorite block under pressure before a global T† phase is established.

  12. Pressure Effect on the Structural Transition and Suppression of the High-Spin State in the Triple-Layer T'-La?Ni?O?

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Cheng, J.-G.; Zhou, J.-S.; Goodenough, J. B.; Zhou, H. D.; Matsubayashi, K.; Uwatoko, Y.; Kong, P. P.; Jin, C. Q.; Yang, W. G.; Shen, G. Y.

    2012-06-01T23:59:59.000Z

    We report a comprehensive high-pressure study on the triple-layer T'-La?Ni?O? with a suite of experimental probes, including structure determination, magnetic, and transport properties up to 50 GPa. Consistent with a recent ab inito calculation, application of hydrostatic pressure suppresses an insulator-metal spin-state transition at Pc?6 GPa. However, a low-spin metallic phase does not emerge after the high-spin state is suppressed to the lowest temperature. For P>20 GPa, the ambient T' structure transforms gradually to a T†-type structure, which involves a structural reconstruction from fluorite La–O?–La blocks under low pressures to rock-salt LaO-LaO blocks under high pressures. Absence of the metallicmore »phase under pressure has been discussed in terms of local displacements of O²? ions in the fluorite block under pressure before a global T† phase is established.« less

  13. Structure Transition in PSS/Lysozyme Complexes: A Chain-Conformation-Driven Process, as Directly Seen by Small Angle Neutron Scattering

    E-Print Network [OSTI]

    Jérémie Gummel; Fabrice Cousin; François Boué

    2009-03-30T23:59:59.000Z

    Measurements of chain conformation in proteins/polyelectrolytes complexes (lysozyme and PSSNa) show that the crossover observed between an open structure -a chain network crosslinked by the proteins, and a globular one - dense globules of ~ 10 nm aggregated in a fractal way, results from a conformation modification prior to the transition. Before showing this, we have widened the parameters range for the observation of the transition. We had shown before that the two structures can be formed depending on chain length (for a given [PSS]/[lysozyme] ratio): gel for large chains, globules for short chains. We show here that the crossover between these two regimes can also be reached as a function of chains concentration or salinity of the buffer. Since all these crossover parameters act on chains overlapping concentration c*, we reinforce the idea of a transition from the dilute to the semi-dilute regime, but c* is shifted compared to pure PSS solutions. In order to understand this, we have measured by SANS the conformation of a single chain of PSS in presence of proteins within the complexes. This is achieved by a specific labeling trick where we take advantage of the fact that lysozyme and hydrogenated PSS chains have the same neutron scattering length density. In the gel structure, the PSS chains keep a wormlike structure as in pure solutions, but their persistence length is strongly reduced, from 50 {\\AA} without proteins to 20 {\\AA} in average with lysozyme. With this value of 20 {\\AA}, we calculate new overlapping thresholds (concentration, mass, ionic strength) in agreement with observed ones. In a second stage, after the globular structure is formed, the PSS chains get a third conformation, no longer wormlike, but more collapsed, within the globules.

  14. Pressure-induced magnetic, structural, and electronic phase transitions in LaFeO{sub 3}: A density functional theory (generalized gradient approximation)?+?U study

    SciTech Connect (OSTI)

    Javaid, Saqib [EMMG, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); National Centre of Physics, Islamabad (Pakistan); Javed Akhtar, M., E-mail: javedakhtar6@gmail.com [EMMG, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan)

    2014-07-14T23:59:59.000Z

    We have investigated the behavior of orthoferrite LaFeO{sub 3} at ambient conditions and under pressure using DFT (generalized gradient approximation (GGA))?+?U approach. Ground state electronic (band gap) and magnetic properties are considerably improved due to the Hubbard correction. Moreover, the experimentally observed pressure-driven phase transition, namely, the simultaneous occurrence of spin crossover, isostructural volume collapse, and drastic reduction in electrical resistance (electronic phase transition) is nicely described by GGA?+?U calculations. In particular, despite a sharp drop in resistance, a small band gap still remains in the low spin state indicating an insulator to semiconductor phase transition, in good agreement with the experiments but in contrast to GGA, which predicts metallic behavior in low spin state. We discuss the origin of variation in electronic structure of LaFeO{sub 3} in low spin state as obtained from GGA to GGA?+?U methods. These results emphasize the importance of correlation effects in describing the pressure-driven phase transition in LaFeO{sub 3} and other rare-earth orthoferrites.

  15. Neutron diffraction study of the crystal structure and structural phase transition of La{sub 0.7}Ca{sub 0.3-x}Sr{sub x}CrO{sub 3} (0<=x<=0.3)

    SciTech Connect (OSTI)

    Omoto, Kazuki [Department of Integrated Sciences in Physics and Biology, College of Humanities and Sciences, Nihon University, 3-25-40 Sakurajousui, Setagaya-ku, Tokyo 156-8550 (Japan); Norberg, Stefan T. [Department of Chemical and Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg (Sweden); ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX (United Kingdom); Hull, Steve [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX (United Kingdom); Aoto, Akimitsu [Department of Integrated Sciences in Physics and Biology, College of Humanities and Sciences, Nihon University, 3-25-40 Sakurajousui, Setagaya-ku, Tokyo 156-8550 (Japan); Hashimoto, Takuya, E-mail: takuya@chs.nihon-u.ac.j [Department of Integrated Sciences in Physics and Biology, College of Humanities and Sciences, Nihon University, 3-25-40 Sakurajousui, Setagaya-ku, Tokyo 156-8550 (Japan)

    2010-02-15T23:59:59.000Z

    The crystal structure of the La{sub 0.7}Ca{sub 0.3-x}Sr{sub x}CrO{sub 3} series, including the compositional and temperature dependence of the structural parameters, has been studied by variable temperature neutron diffraction measurements. The extent of the distortions from the ideal cubic perovskite structure has been evaluated quantitatively using the average bond lengths and the mean volumes of the [CrO{sub 6}] octahedron and [(La/Ca/Sr)O{sub 12}] polyhedron, and has been shown to decrease with increase of Sr content or temperature. At the structural phase transition from the orthorhombic (Pnma) structure to the rhombohedral (R3-barc) one, the volume of the [CrO{sub 6}] octahedron decreases whereas that of the [(La/Ca/Sr)O{sub 12}] polyhedron shows little difference, resulting in an overall decrease in the level of distortion. The change in the degree of distortion at the phase transition decreases with increase of Sr content, in agreement with the smaller variation of the enthalpy and volume for the specimens with higher Sr content. - Graphical abstract: Temperature dependence of parameter, PHI, representing the extent of distortion from the ideal cubic perovskite structure, for La{sub 0.7}Ca{sub 0.3}CrO{sub 3} (diamonds) and La{sub 0.7}Ca{sub 0.15}Sr{sub 0.15}CrO{sub 3} (circles) calculated from neutron diffraction patterns.

  16. Dynamics of the phase transitions in the system of nonequilibrium charge carriers in quantum-dimensional Si{sub 1?x}Ge{sub x}/Si structures

    SciTech Connect (OSTI)

    Bagaev, V. S.; Krivobok, V. S., E-mail: krivobok@lebedev.ru; Nikolaev, S. N.; Onishchenko, E. E.; Pruchkina, A. A.; Aminev, D. F.; Skorikov, M. L. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Lobanov, D. N.; Novikov, A. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2013-11-15T23:59:59.000Z

    The dynamics of the phase transition from an electron-hole plasma to an exciton gas is studied during pulsed excitation of heterostructures with Si{sub 1?x}Ge{sub x}/Si quantum wells. The scenario of the phase transition is shown to depend radically on the germanium content in the Si{sub 1?x}Ge{sub x} layer. The electron-hole system decomposes into a rarefied exciton and a dense plasma phases for quantum wells with a germanium content x = 3.5% in the time range 100–500 ns after an excitation pulse. In this case, the electron-hole plasma existing in quantum wells has all signs of an electron-hole liquid. A qualitatively different picture of the phase transition is observed for quantum wells with x = 9.5%, where no separation into phases with different electronic spectra is detected. The carrier recombination in the electron-hole plasma leads a gradual weakening of screening and the appearance of exciton states. For a germanium content of 5–7%, the scenario of the phase transition is complex: 20–250 ns after an excitation pulse, the properties of the electron-hole system are described in terms of a homogeneous electron-hole plasma, whereas its separation into an electron-hole liquid and an exciton gas is detected after 350 ns. It is shown that, for the electron-hole liquid to exist in quantum wells with x = 5–7% Ge, the exciton gas should have a substantially higher density than in quantum wells with x = 3.5% Ge. This finding agrees with a decrease in the depth of the local minimum of the electron-hole plasma energy with increasing germanium concentration in the SiGe layer. An increase in the density of the exciton gas coexisting with the electron-hole liquid is shown to enhance the role of multiparticle states, which are likely to be represented by trions T{sup +} and biexcitons, in the exciton gas.

  17. High-resolution SIMS depth profiling of nanolayers.

    SciTech Connect (OSTI)

    Baryshev, S. V.; Zinovev, A. V.; Tripa, C. E.; Pellin, M. J.; Peng, Q.; Elam, J. W.; Veryovkin, I. V. (Energy Systems); ( MSD)

    2012-10-15T23:59:59.000Z

    Although the fundamental physical limits for depth resolution of secondary ion mass spectrometry are well understood in theory, the experimental work to achieve and demonstrate them is still ongoing. We report results of high-resolution TOF SIMS (time-of-flight secondary ion mass spectrometry) depth profiling experiments on a nanolayered structure, a stack of 16 alternating MgO and ZnO {approx}5.5 nm layers grown on a Si substrate by atomic layer deposition. The measurements were performed using a newly developed approach implementing a low-energy direct current normally incident Ar{sup +} ion beam for ion milling (250 eV and 500 eV energy), in combination with a pulsed 5 keV Ar{sup +} ion beam at 60{sup o} incidence for TOF SIMS analysis. By this optimized arrangement, a noticeably improved version of the dual-beam (DB) approach to TOF SIMS depth profiling is introduced, which can be dubbed gentleDB. The mixing-roughness-information model was applied to detailed analysis of experimental results. It revealed that the gentleDB approach allows ultimate depth resolution by confining the ion beam mixing length to about two monolayers. This corresponds to the escape depth of secondary ions, the fundamental depth resolution limitation in SIMS. Other parameters deduced from the measured depth profiles indicated that a single layer thickness is equal to 6 nm so that the 'flat' layer thickness d is 3 nm and the interfacial roughness {sigma} is 1.5 nm, thus yielding d + 2{sigma} = 6 nm. We have demonstrated that gentleDB TOF SIMS depth profiling with noble gas ion beams is capable of revealing the structural features of a stack of nanolayers, resolving its original surface and estimating the roughness of interlayer interfaces, information which is difficult to obtain by traditional approaches.

  18. Roughness of the SiC/SiO{sub 2} vicinal interface and atomic structure of the transition layers

    SciTech Connect (OSTI)

    Liu, Peizhi; Li, Guoliang; Duscher, Gerd, E-mail: gduscher@utk.edu [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, Tennessee 37996 (United States); Sharma, Yogesh K.; Ahyi, Ayayi C.; Isaacs-Smith, Tamara; Williams, John R.; Dhar, Sarit [Department of Physics, Auburn University, Auburn, Alabama 36849 (United States)

    2014-11-01T23:59:59.000Z

    The SiC/SiO{sub 2} interface is generally considered to be the cause for the reduced electron mobility of SiC power devices. Previous studies have shown a correlation between the mobility and the transition layer width at the SiC/SiO{sub 2} interface. The authors investigated this interface with atomic resolution Z-contrast imaging and electron energy-loss spectroscopy, and discovered that this transition region was due to the roughness of the vicinal interface. The roughness of a vicinal interface consisted of atomic steps and facets deviating from the ideal off-axis cut plane. The authors conclude that this roughness is limiting the mobility in the channels of SiC MOSFETs.

  19. Heteroepitaxial VO{sub 2} thin films on GaN: Structure and metal-insulator transition characteristics

    SciTech Connect (OSTI)

    Zhou You; Ramanathan, Shriram [Harvard School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States)

    2012-10-01T23:59:59.000Z

    Monolithic integration of correlated oxide and nitride semiconductors may open up new opportunities in solid-state electronics and opto-electronics that combine desirable functional properties of both classes of materials. Here, we report on epitaxial growth and phase transition-related electrical properties of vanadium dioxide (VO{sub 2}) thin films on GaN epitaxial layers on c-sapphire. The epitaxial relation is determined to be (010){sub vo{sub 2}} parallel (0001){sub GaN} parallel (0001){sub A1{sub 2O{sub 3}}} and [100]{sub vo{sub 2}} parallel [1210]{sub GaN} parallel [0110]{sub A1{sub 2O{sub 3}}} from x-ray diffraction. VO{sub 2} heteroepitaxial growth and lattice mismatch are analyzed by comparing the GaN basal plane (0001) with the almost close packed corrugated oxygen plane in vanadium dioxide and an experimental stereographic projection describing the orientation relationship is established. X-ray photoelectron spectroscopy suggests a slightly oxygen rich composition at the surface, while Raman scattering measurements suggests that the quality of GaN layer is not significantly degraded by the high-temperature deposition of VO{sub 2}. Electrical characterization of VO{sub 2} films on GaN indicates that the resistance changes by about four orders of magnitude upon heating, similar to epitaxial VO{sub 2} films grown directly on c-sapphire. It is shown that the metal-insulator transition could also be voltage-triggered at room temperature and the transition threshold voltage scaling variation with temperature is analyzed in the framework of a current-driven Joule heating model. The ability to synthesize high quality correlated oxide films on GaN with sharp phase transition could enable new directions in semiconductor-photonic integrated devices.

  20. Determination of structure and phase transition of light element nanocomposites in mesoporous silica: case study of NH3BH3 in MCM-41

    SciTech Connect (OSTI)

    Kim, Hyun Jeong; Karkamkar, Abhijeet J.; Autrey, Thomas; Chupas, Peter; Proffen, Thomas E.

    2009-09-30T23:59:59.000Z

    The structure of ammonia borane (AB), NH3BH3, infused in mesoporous silica MCM-41 and its evolution over the temperature range of 80 to 300 K was investigated using the atomic pair distribution function (PDF) analysis of synchrotron X-ray powder diffraction data in order to understand the origin of improved dehydrogenation properties of the system. Our study shows how X-ray PDF analysis can be used to elucidate the structure of light guest species loaded in mesoporous silica materials despite of its low scattering power of composed elements (N, B, and H) compared to its host (SiO2). PDF analyses of two AB-loaded compositions with weight ratio AB:MCM-41=1:1 and 3:1 provide a strong evidence that AB aggregate, previously found in AB:MCM-41?1:1 samples, is same species as neat AB. For both of them an orthorhombic to tetragonal structural phase transition occurs at 225 K on warming. On the other hand, AB residing inside meso-pores, which is found in AB:MCM-41=1:2 sample, does not undergo such phase transition. It rather stays in tetragonal phase over a wide temperature range of 110 to 240 K and starts to lose structural correlation above 240 K. This strongly suggests that nano-confinement of AB inside meso-pores stabilizes high temperature tetragonal phase at much lower temperature. These results provide important clues to two critical questions: why nan-compositions of AB leads dehydrogenation to lower temperature and why the neat AB like propoerties are recovered at high AB loading samples. This work was supported by the US Department of Energy Office of Basic Energy Sciences, Chemical Sciences program. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  1. Pressure induced magneto-structural phase transitions in layered RMn{sub 2}X{sub 2} compounds (invited)

    SciTech Connect (OSTI)

    Kennedy, Shane, E-mail: sjk@ansto.gov.au [The Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Wang, Jianli [The Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Institute for Superconductivity and Electronic Materials, University of Wollongong, Wollongong, NSW (Australia); Campbell, Stewart [School of Physical, Environmental and Mathematical Sciences, University of New South Wales, Canberra, ACT (Australia); Hofmann, Michael [Forschungs-Neutronenquelle Heinz Maier-Leibnitz, Technische Universität München, Garching (Germany); Dou, Shixue [Institute for Superconductivity and Electronic Materials, University of Wollongong, Wollongong, NSW (Australia)

    2014-05-07T23:59:59.000Z

    We have studied a range of pseudo-ternaries derived from the parent compound PrMn{sub 2}Ge{sub 2}, substituting for each constituent element with a smaller one to contract the lattice. This enables us to observe the magneto-elastic transitions that occur as the Mn-Mn nearest neighbour distance is reduced and to assess the role of Pr on the magnetism. Here, we report on the PrMn{sub 2}Ge{sub 2?x}Si{sub x}, Pr{sub 1?x}Y{sub x}Mn{sub 2}Ge{sub 2}, and PrMn{sub 2?x}Fe{sub x}Ge{sub 2} systems. The pressure produced by chemical substitution in these pseudo-ternaries is inherently non-uniform, with local pressure variations dependent on the local atomic distribution. We find that concentrated chemical substitution on the R or X site (e.g., in Pr{sub 0.5}Y{sub 0.5}Mn{sub 2}Ge{sub 2} and PrMn{sub 2}Ge{sub 0.8}Si{sub 1.2}) can produce a separation into two distinct magnetic phases, canted ferromagnetic and canted antiferromagnetic, with a commensurate phase gap in the crystalline lattice. This phase gap is a consequence of the combination of phase separation and spontaneous magnetostriction, which is positive on transition to the canted ferromagnetic phase and negative on transition to the canted antiferromagnetic phase. Our results show that co-existence of canted ferromagnetic and antiferromagnetic phases depends on chemical pressure from the rare earth and metalloid sites, on local lattice strain distributions and on applied magnetic field. We demonstrate that the effects of chemical pressure bear close resemblance to those of mechanical pressure on the parent compound.

  2. Pressure Effect on the Structural Transition and Suppression of the High-Spin State in the Triple-Layer T'-La?Ni?O?

    SciTech Connect (OSTI)

    Cheng, J.-G.; Zhou, J.-S.; Goodenough, J. B.; Zhou, H. D.; Matsubayashi, K.; Uwatoko, Y.; Kong, P. P.; Jin, C. Q.; Yang, W. G.; Shen, G. Y.

    2012-06-01T23:59:59.000Z

    We report a comprehensive high-pressure study on the triple-layer T'-La?Ni?O? with a suite of experimental probes, including structure determination, magnetic, and transport properties up to 50 GPa. Consistent with a recent ab inito calculation, application of hydrostatic pressure suppresses an insulator-metal spin-state transition at Pc?6 GPa. However, a low-spin metallic phase does not emerge after the high-spin state is suppressed to the lowest temperature. For P>20 GPa, the ambient T' structure transforms gradually to a T-type structure, which involves a structural reconstruction from fluorite La–O?–La blocks under low pressures to rock-salt LaO-LaO blocks under high pressures. Absence of the metallic phase under pressure has been discussed in terms of local displacements of O²? ions in the fluorite block under pressure before a global T† phase is established.

  3. POLARIMETRIC IMAGING OF LARGE CAVITY STRUCTURES IN THE PRE-TRANSITIONAL PROTOPLANETARY DISK AROUND PDS 70: OBSERVATIONS OF THE DISK

    SciTech Connect (OSTI)

    Hashimoto, J.; Hayashi, M. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Dong, R.; Zhu, Z.; Brandt, T. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Kudo, T.; Egner, S.; Guyon, O.; Hayano, Y. [Subaru Telescope, 650 North A'ohoku Place, Hilo, HI 96720 (United States); Honda, M. [Kanagawa University, 2946 Tsuchiya, Hiratsuka, Kanagawa 259-1293 (Japan); McClure, M. K. [Department of Astronomy, University of Michigan, 500 Church Street, 830 Dennison Building, Ann Arbor, MI 48109 (United States); Muto, T. [Division of Liberal Arts, Kogakuin University, 1-24-2, Nishi-Shinjuku, Shinjuku-ku, Tokyo 163-8677 (Japan); Wisniewski, J. [University of Washington, Seattle, WA 98195 (United States); Abe, L. [Laboratoire Hippolyte Fizeau, UMR6525, Universite de Nice Sophia-Antipolis, 28, avenue Valrose, F-06108 Nice Cedex 02 (France); Brandner, W.; Carson, J.; Feldt, M. [Max Planck Institute for Astronomy, D-69117 Heidelberg (Germany); Fukagawa, M. [Osaka University, 1-1, Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Goto, M. [Universitaets-Sternwarte Muenchen, Scheinerstr. 1, D-81679 Munich (Germany); Grady, C. A., E-mail: jun.hashimoto@nao.ac.jp [Exoplanets and Stellar Astrophysics Laboratory, Code 667, Goddard Space Flight Center, Greenbelt, MD 20771 (United States); and others

    2012-10-10T23:59:59.000Z

    We present high-resolution H-band polarized intensity (FWHM = 0.''1: 14 AU) and L'-band imaging data (FWHM = 0.''11: 15 AU) of the circumstellar disk around the weak-lined T Tauri star PDS 70 in Centaurus at a radial distance of 28 AU (0.''2) up to 210 AU (1.''5). In both images, a giant inner gap is clearly resolved for the first time, and the radius of the gap is {approx}70 AU. Our data show that the geometric center of the disk shifts by {approx}6 AU toward the minor axis. We confirm that the brown dwarf companion candidate to the north of PDS 70 is a background star based on its proper motion. As a result of spectral energy distribution fitting by Monte Carlo radiative transfer modeling, we infer the existence of an optically thick inner disk at a few AU. Combining our observations and modeling, we classify the disk of PDS 70 as a pre-transitional disk. Furthermore, based on the analysis of L'-band imaging data, we put an upper limit of {approx}30 to {approx}50 M{sub J} on the mass of companions within the gap. Taking into account the presence of the large and sharp gap, we suggest that the gap could be formed by dynamical interactions of sub-stellar companions or multiple unseen giant planets in the gap.

  4. Transition from soft- to hard-Pomeron in the structure functions of hadrons at small-$x$ from holography

    E-Print Network [OSTI]

    Akira Watanabe; Katsuhiko Suzuki

    2012-06-05T23:59:59.000Z

    We study the nucleon and pion structure functions at small Bjorken-$x$ region in the framework of holographic QCD with a special emphasis on the roles of AdS space wave functions. Using the BPST kernel for the Pomeron exchange and calculating its coupling to target hadrons in the AdS space, we obtain $F_2$ structure functions at the small-$x$. Results for the proton $F^p_2$ as well as the pion $F^\\pi_2$ are consistent with experimental data of the deep inelastic scattering and the forward electroproduction of a neutron. Observed $Q^2$ dependence of the Pomeron intercept is well reproduced from soft non-perturbatibve $(Q^2 \\sim 0)$ to hard perturbative $(Q^2 \\gg 1 GeV^2)$ region. We find the interplay between soft and hard Pomerons is closely related with behavior of AdS wave functions of hadrons and the virtual photon.

  5. A conformational transition in the structure of a 2'-thiomethyl-modified DNA visualized at high resolution

    SciTech Connect (OSTI)

    Pallan, Pradeep S.; Prakash, Thazha P.; Li, Feng; Eoff, Robert L.; Manoharan, Muthiah; Egli, Martin; (Isis Pharm.); (Alnylam Pharm.); (Vanderbilt)

    2009-06-17T23:59:59.000Z

    Crystal structures of A-form and B-form DNA duplexes containing 2'-S-methyl-uridines reveal that the modified residues adopt a RNA-like C3'-endo pucker, illustrating that the replacement of electronegative oxygen at the 2'-carbon of RNA by sulfur does not appear to fundamentally alter the conformational preference of the sugar in the oligonucleotide context and sterics trump stereoelectronics.

  6. Journal of Superconductivity, Vol. 5, No. 4, 1992 Magnetic Penetration Depth Measurements in

    E-Print Network [OSTI]

    Anlage, Steven

    of superconductivity is the diamagnetic response of a superconductor below its transition temperature To. The abilityJournal of Superconductivity, Vol. 5, No. 4, 1992 Magnetic Penetration Depth Measurements in Cuprate Superconductors Steven M. AnlageI and Dong-Ho Wut Received 16 April 1992 We examine recent results

  7. The determination of interfacial structure and phase transitions in Al/Cu and Al/Ni interfaces by means of surface extended x-ray absorption fine structure

    SciTech Connect (OSTI)

    Barrera, E.V. (Rice Univ., Houston, TX (United States). Dept. of Mechanical Engineering and Materials Science); Heald, S.M. (Brookhaven National Lab., Upton, NY (United States))

    1991-01-01T23:59:59.000Z

    Surface extended x-ray absorption fine structure (SEXAFS) was used to investigate the interfacial conditions of Al/Cu and Al/Ni shallow buried interfaces. Previous studies using glancing angle extended x-ray absorption fine structure, x-ray reflectivity, photoemission, and SEXAFS produced conflicting results as to whether or not the interfaces between Al and Cu and Al and Ni were reacted upon room temperature deposition. In this study polycrystalline bilayers of Al/Cu and Al/Ni and trilayers of Al/Cu/Al and Al/Ni/Al were deposited on tantalum foil at room temperature in ultra high vacuum and analyzed to evaluate the reactivity of these systems on a nanometer scale. It become overwhelming apparent that the interfacial phase reactions were a function of the vacuum conditions. Samples deposited with the optimum vacuum conditions showed reaction products upon deposition at room temperature which were characterized by comparisons to standards and by least squares fitting the be CuAl{sub 2} and NiAl{sub 3} respectively. The results of this study that the reacted zone thicknesses were readily dependent on the deposition parameters. For both Al on Cu and Al on Ni as well as the metal on Al conditions 10{Angstrom} reaction zones were observed. These reaction zones were smaller than that observed for bilayers of Al on Cu (30{Angstrom}) and Al on Ni (60{Angstrom}) where deposition rates were much higher and samples were much thicker. The reaction species are evident by SEXAFS, where the previous photoemission studies only indicated that changes had occurred. Improved vacuum conditions as compared to the earlier experiments is primarily the reason reactions on deposition were seen in this study as compared to the earlier SEXAFS studies.

  8. The determination of interfacial structure and phase transitions in Al/Cu and Al/Ni interfaces by means of surface extended x-ray absorption fine structure

    SciTech Connect (OSTI)

    Barrera, E.V. [Rice Univ., Houston, TX (United States). Dept. of Mechanical Engineering and Materials Science; Heald, S.M. [Brookhaven National Lab., Upton, NY (United States)

    1991-12-31T23:59:59.000Z

    Surface extended x-ray absorption fine structure (SEXAFS) was used to investigate the interfacial conditions of Al/Cu and Al/Ni shallow buried interfaces. Previous studies using glancing angle extended x-ray absorption fine structure, x-ray reflectivity, photoemission, and SEXAFS produced conflicting results as to whether or not the interfaces between Al and Cu and Al and Ni were reacted upon room temperature deposition. In this study polycrystalline bilayers of Al/Cu and Al/Ni and trilayers of Al/Cu/Al and Al/Ni/Al were deposited on tantalum foil at room temperature in ultra high vacuum and analyzed to evaluate the reactivity of these systems on a nanometer scale. It become overwhelming apparent that the interfacial phase reactions were a function of the vacuum conditions. Samples deposited with the optimum vacuum conditions showed reaction products upon deposition at room temperature which were characterized by comparisons to standards and by least squares fitting the be CuAl{sub 2} and NiAl{sub 3} respectively. The results of this study that the reacted zone thicknesses were readily dependent on the deposition parameters. For both Al on Cu and Al on Ni as well as the metal on Al conditions 10{Angstrom} reaction zones were observed. These reaction zones were smaller than that observed for bilayers of Al on Cu (30{Angstrom}) and Al on Ni (60{Angstrom}) where deposition rates were much higher and samples were much thicker. The reaction species are evident by SEXAFS, where the previous photoemission studies only indicated that changes had occurred. Improved vacuum conditions as compared to the earlier experiments is primarily the reason reactions on deposition were seen in this study as compared to the earlier SEXAFS studies.

  9. A Change of Solar He II EUV Global Network Structure of the Transition Region as an Indicator of Geo-Effectiveness of Solar Minima

    E-Print Network [OSTI]

    Didkovsky, Leonid

    2013-01-01T23:59:59.000Z

    Solar activity during 2007--2009 was very low, causing anomalously low thermospheric density. A comparison of solar extreme ultraviolet (EUV) irradiance in the He II spectral band (26 to 34 nm) from the Solar Extreme ultraviolet Monitor (SEM), one of instruments on the Charge Element and Isotope Analysis System (CELIAS) onboard of the Solar and Heliospheric Observatory (SOHO) for the two latest solar minima showed a decrease of the absolute irradiance of about 15 +- 6 % during the solar minimum between Cycles 23 and 24 compared with the Cycles 22/23 minimum when a yearly running mean filter was used. We found that some local, shorter-term minima including those with the same absolute EUV flux in the SEM spectral band show a larger concentration of spatial power in the global network structure from the 30.4 nm SOHO Extreme ultraviolet Imaging Telescope (EIT) images for the local minimum of 1996 compared with the minima of 2008--2011. We interpret this larger concentration of spatial power in the transition reg...

  10. Gender, Truth & Transition

    E-Print Network [OSTI]

    Ní Aoláin, Pionnuala; Turner, Catherine

    2007-01-01T23:59:59.000Z

    50. Id. GENDER, TRUTH & TRANSITION contested, as evidencedG. Teitel, Human Rights in Transition: Transitional JusticeU.N. GENDER, TRUTH & TRANSITION Organization of American

  11. Source depth for solar p-modes

    E-Print Network [OSTI]

    Pawan Kumar; Sarbani Basu

    2000-06-15T23:59:59.000Z

    Theoretically calculated power spectra are compares with observed solar p-mode velocity power spectra over a range of mode degree and frequency. The depth for the sources responsible for exciting p-modes of frequency 2.0 mHz is determined from the asymmetry of their power spectra and found to be about 800 km below the photosphere for quadrupole sources and 150 km if sources are dipole. The source depth for high frequency oscillations of frequency greater than about 6 mHz is 180 (50) km for quadrupole (dipole) sources.

  12. TRANSITION DE MOTT METAL-INSULATOR TRANSITIONS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    TRANSITION DE MOTT METAL-INSULATOR TRANSITIONS IN TRANSITION METAL OXIDES by D. B. McWHAN, A. MENTH oxydes de metaux de transition on observe une transition d'isolant a metal puis de metal a isolant de type Mott lorsque l'on augmentelenombre d'electrons d. Danslesysthe(V1-~Cr~)203une transition de Mott

  13. Depth and Depth-Color Coding using Shape-Adaptive Wavelets

    E-Print Network [OSTI]

    Do, Minh N.

    -view autostereoscopic displays, 3D-TV is expected to be the next evolution of television after high definition. Three Abstract We present a novel depth and depth-color codec aimed at free-viewpoint 3D-TV. The proposed codec is implemented by shape-adaptive lifting, which enables fast computations and perfect reconstruction. We derive

  14. Depth Partitions, Hierarchical Network Structure, and Networks-Affect-Pricing

    E-Print Network [OSTI]

    White, Douglas R.

    heavey industries 4 5596 37 sony sony 4 417 37 canon canon 7 217 34 ebara ebara 8 4043 29 tokimec tokimec

  15. Effective Incentive Structures

    Broader source: Energy.gov [DOE]

    Presents an in-depth look at effective incentive structures, how to clarify your program goals, and tips to plan for the long term.

  16. Defense-in-Depth, How Department of Energy Implements Radiation...

    Energy Savers [EERE]

    Defense-in-Depth, How Department of Energy Implements Radiation Protection in Low Level Waste Disposal Defense-in-Depth, How Department of Energy Implements Radiation Protection in...

  17. Africa Aerosol Optical Depth Obtained From MISR

    E-Print Network [OSTI]

    Frank, Thomas D.

    OpticalDepth Central African Republic Chad Djibouti Egypt Ethiopia Libya Kenya Somalia Sudan Uganda #12;Southern Africa Ethiopia Libya Kenya Somalia Sudan Uganda #12;Southern Africa 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Mean Seasonal

  18. Collision Avoidance in Depth Space I. INTRODUCTION

    E-Print Network [OSTI]

    De Luca, Alessandro

    ; compute distances between the obstacles and the robot; optionally project the results in the CartesianCollision Avoidance in Depth Space I. INTRODUCTION When humans and robots share the same work space, safety is the primary issue of concern [8]. Secondary but not negligible is to prevent robot damages due

  19. Structural phase transition, narrow band gap, and room-temperature ferromagnetism in [KNbO{sub 3}]{sub 1?x}[BaNi{sub 1/2}Nb{sub 1/2}O{sub 3??}]{sub x} ferroelectrics

    SciTech Connect (OSTI)

    Zhou, Wenliang; Yang, Pingxiong, E-mail: pxyang@ee.ecnu.edu.cn; Chu, Junhao [Key Laboratory of Polar Materials and Devices, Ministry of Education, Department of Electronic Engineering, East China Normal University, Shanghai 200241 (China); Deng, Hongmei [Instrumental Analysis and Research Center, Institute of Materials, Shanghai University, 99 Shangda Road, Shanghai 200444 (China)

    2014-09-15T23:59:59.000Z

    Structural phase transition, narrow band gap (E{sub g}), and room-temperature ferromagnetism (RTFM) have been observed in the [KNbO{sub 3}]{sub 1?x}[BaNi{sub 1/2}Nb{sub 1/2}O{sub 3??}]{sub x} (KBNNO) ceramics. All the samples have single phase perovskite structure, but exhibit a gradual transition behaviour from the orthorhombic to a cubic structure with the increase of x. Raman spectroscopy analysis not only corroborates this doping-induced change in normal structure but also shows the local crystal symmetry for x ? 0.1 compositions to deviate from the idealized cubic perovskite structure. A possible mechanism for the observed specific changes in lattice structure is discussed. Moreover, it is noted that KBNNO with compositions x?=?0.1–0.3 have quite narrow E{sub g} of below 1.5?eV, much smaller than the 3.2?eV band gap of parent KNbO{sub 3} (KNO), which is due to the increasing Ni 3d electronic states within the gap of KNO. Furthermore, the KBNNO materials present RTFM near a tetragonal to cubic phase boundary. With increasing x from 0 to 0.3, the magnetism of the samples develops from diamagnetism to ferromagnetism and paramagnetism, originating from the ferromagnetic–antiferromagnetic competition. These results are helpful in the deeper understanding of phase transitions, band gap tunability, and magnetism variations in perovskite oxides and show the potential role, such materials can play, in perovskite solar cells and multiferroic applications.

  20. Oral English development and its impact on emergent reading achievement: a comparative study of transitional bilingual and structured english immersion models

    E-Print Network [OSTI]

    Tong, Fuhui

    2009-05-15T23:59:59.000Z

    This quantitative study derived from an on-going federal experimental research project targeting Spanish-speaking English language learners (ELLs) receiving services in four program models: control/experimental transitional bilingual education (TBE...

  1. Consequentialism in Transition

    E-Print Network [OSTI]

    Coons, Christian

    2008-01-01T23:59:59.000Z

    the value of state transitions will allow us to sayConsequentialism in Transition Christian Coons Bowling Greenvalue of the state transitions, and not the states of

  2. Sampling diffusive transition paths

    E-Print Network [OSTI]

    F. Miller III, Thomas

    2009-01-01T23:59:59.000Z

    Sampling di?usive transition paths Thomas F. Miller III ?the algorithm to sample the transition path ensemble for thedynamics I. INTRODUCTION Transition path sampling (TPS) is a

  3. Structural phase transition and electrode characteristics of LiMn{sub 2{minus}x}Mg{sub x}O{sub 4} positive electrode material for the lithium secondary battery

    SciTech Connect (OSTI)

    Idemoto, Y.; Udagawa, K.; Koura, N.; Richardson, J. W., Jr.; Takeuchi, K.; Loong, C.-K.

    1999-12-10T23:59:59.000Z

    With in mind improving the cycle performance of 4V class lithium manganese oxide positive electrode material for the lithium secondary battery, the authors have been investigating the effects of partial substitution of Mn by another metal. The crystal phase transition in the quaternary spinel LiMn{sub 2{minus}x}Mg{sub x}O{sub 4} was studied by neutron powder diffraction at 200K and DSC measurements at low temperatures. They find that substituting Mn by Mg resulted in a more stable crystal structure with the Jahn-Teller transition suppressed down to low temperature. The charge-discharge characteristics of these positive electrode active materials were investigated at 4V range. Although the discharge capacity decreased with increasing Mg content, the cycle performance was improved with increasing Mg content.

  4. Identification Of Rippability And Bedrock Depth Using Seismic Refraction

    SciTech Connect (OSTI)

    Ismail, Nur Azwin; Saad, Rosli; Nawawi, M. N. M; Muztaza, Nordiana Mohd; El Hidayah Ismail, Noer [Geophysics Section, School of Physics, 11800 Universiti Sains Malaysia, Pulau Pinang (Malaysia); Mohamad, Edy Tonizam [Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia)

    2010-12-23T23:59:59.000Z

    Spatial variability of the bedrock with reference to the ground surface is vital for many applications in geotechnical engineering to decide the type of foundation of a structure. A study was done within the development area of Mutiara Damansara utilising the seismic refraction method using ABEM MK8 24 channel seismograph. The geological features of the subsurface were investigated and velocities, depth to the underlying layers were determined. The seismic velocities were correlated with rippability characteristics and borehole records. Seismic sections generally show a three layer case. The first layer with velocity 400-600 m/s predominantly consists of soil mix with gravel. The second layer with velocity 1600-2000 m/s is suggested to be saturated and weathered area. Both layers forms an overburden and generally rippable. The third layer represents granite bedrock with average depth and velocity 10-30 m and >3000 m/s respectively and it is non-rippable. Steep slope on the bedrock are probably the results of shear zones.

  5. Accurate hydrogen depth profiling by reflection elastic recoil detection analysis

    SciTech Connect (OSTI)

    Verda, R. D. (Raymond D.); Tesmer, Joseph R.; Nastasi, Michael Anthony,; Bower, R. W. (Robert W.)

    2001-01-01T23:59:59.000Z

    A technique to convert reflection elastic recoil detection analysis spectra to depth profiles, the channel-depth conversion, was introduced by Verda, et al [1]. But the channel-depth conversion does not correct for energy spread, the unwanted broadening in the energy of the spectra, which can lead to errors in depth profiling. A work in progress introduces a technique that corrects for energy spread in elastic recoil detection analysis spectra, the energy spread correction [2]. Together, the energy spread correction and the channel-depth conversion comprise an accurate and convenient hydrogen depth profiling method.

  6. Polarizabilities of the 87Sr Clock Transition

    E-Print Network [OSTI]

    Shi, C; Eismann, U; Zawada, M; Lorini, L; Targat, R Le; Lodewyck, J

    2015-01-01T23:59:59.000Z

    In this paper, we propose an in-depth review of the vector and tensor polarizabilities of the two energy levels of the 87Sr clock transition whose measurement was reported in [P. G. Westergaard et al., Phys. Rev. Lett. 106, 210801 (2011)]. We conduct a theoretical calculation that reproduces the measured coefficients. In addition, we detail the experimental conditions used for their measurement in two Sr optical lattice clocks, and exhibit the quadratic behaviour of the vector and tensor shifts with the depth of the trapping potential and evaluate their impact on the accuracy of the clock.

  7. Monazite Th-Pb age depth profiling

    SciTech Connect (OSTI)

    Grove, M.; Harrison, T.M. [Univ. of California, Los Angeles, CA (United States)] [Univ. of California, Los Angeles, CA (United States)

    1999-06-01T23:59:59.000Z

    The significant capabilities of the ion microprobe for thermochronometric investigations of geologic materials remain largely unexploited. Whereas {sup 208}Pb/{sup 232}Th spot analysis allows {approximately} 10-mm-scale imaging of Pb loss profiles or overgrowths in sectioned monazite grains, the spatial resolution offered by depth profiling into the surface region of natural crystals is more than two orders of magnitude higher. The authors document here the ability of the high-resolution ion microprobe to detect {sup 208}Pb/{sup 232}Th age differences of < 1 m.y. with better than 0.05 {micro}m depth resolution in the outer micron of Tertiary monazites from the hanging wall of the Himalayan Main Central thrust. Age gradients on this scale are inaccessible to ion microprobe spot analysis or conventional thermal ionization mass spectrometry. Interpretation of the near-surface {sup 208}Pb distributions with available monazite Pb diffusion data illustrates the potential of the approach for recovering continuous, high-temperature thermal history information not previously available.

  8. Revised Transition Probabilities for Fe XXV Relativistic CI Calculations

    E-Print Network [OSTI]

    Johnson, Walter R.

    Revised Transition Probabilities for Fe XXV Relativistic CI Calculations W. R. Johnson1 and U are provided for transition probabilities between fine-structure components of levels with n 6 in FeXXV. Earlier published data for transitions between fine-structure levels in FeXXV is found to in error

  9. Gulf of Mexico Proved Reserves By Water Depth, 2009

    Gasoline and Diesel Fuel Update (EIA)

    Gulf of Mexico Proved Reserves and Production by Water Depth, 2009 1 Gulf of Mexico Proved Reserves and Production by Water Depth The Gulf of Mexico Federal Offshore region (GOM...

  10. First-principles calculations of the electronic structure, phase...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    calculations of the electronic structure, phase transition and properties of ZrSiO4 polymorphs. First-principles calculations of the electronic structure, phase transition and...

  11. Steady periodic waves bifurcating for fixed-depth rotational flows

    E-Print Network [OSTI]

    consider steady periodic water waves for rotational flows with a specified fixed-depth over a flat bed. We the existence of steady periodic water waves for rotational flows with a specified fixed depth over a flat bedSteady periodic waves bifurcating for fixed-depth rotational flows David Henry School

  12. Statistical Data Depth and the Graphics Hardware Shankar Krishnan

    E-Print Network [OSTI]

    Mustafa, Nabil Hassan

    by NSF under grants CCR-00-86013 EIA-98-70724, EIA-99-72879, EIA-01-31905, and CCR-02-04118. 1 #12;Figure). Organization. We first survey various definitions of statistical depth, and the related computa- tional, and the region of all points with depth greater than some integer . Now, we survey various depth measures

  13. Analysis of Nuclear Quantum Phase Transitions

    SciTech Connect (OSTI)

    Li, Z. P.; Meng, J. [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Niksic, T.; Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb (Croatia); Lalazissis, G. A. [Department of Theoretical Physics, Aristotle University of Thessaloniki, GR-54124 (Greece); Ring, P. [Physik-Department der Technischen Universitaet Muenchen, D-85748 Garching (Germany)

    2009-08-26T23:59:59.000Z

    A microscopic analysis, based on nuclear energy density functionals, is presented for shape phase transitions in Nd isotopes. Low-lying excitation spectra and transition probabilities are calculated starting from a five-dimensional Hamiltonian, with parameters determined by constrained relativistic mean-field calculations for triaxial shapes. The results reproduce available data, and show that there is an abrupt change of structure at N = 90, that corresponds to a first-order quantum phase transition between spherical and axially deformed shapes.

  14. An energy spread correction for ERDA hydrogen depth profiling

    SciTech Connect (OSTI)

    Verda, R. D. (Raymond D.); Nastasi, Michael Anthony,

    2002-01-01T23:59:59.000Z

    A technique for hydrogen depth profiling by reflection elastic recoil detection analysis called the channel-depth conversion was introduced by Verda, et al.' However, the energy spread in elastic recoil detection analysis spectra, which causes a broadening in the energy range and leads to errors in depth profiling, was not addressed by this technique. Here we introduce a technique to addresses this problem, called the energy spread correction. Together, the energy spread correction and the channel-depth conversion techniques comprise the depth profiling method presented in this work.

  15. Supersaturating silicon with transition metals by ion implantation and pulsed laser melting

    SciTech Connect (OSTI)

    Recht, Daniel; Aziz, Michael J. [Harvard School of Engineering and Applied Sciences, Cambridge, Massachusetts 02138 (United States)] [Harvard School of Engineering and Applied Sciences, Cambridge, Massachusetts 02138 (United States); Smith, Matthew J.; Grade?ak, Silvija [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Charnvanichborikarn, Supakit; Williams, James S. [Research School of Physics and Engineering, The Australian National University, Canberra, ACT (Australia)] [Research School of Physics and Engineering, The Australian National University, Canberra, ACT (Australia); Sullivan, Joseph T.; Winkler, Mark T.; Buonassisi, Tonio [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge Massachusetts 02139 (United States)] [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge Massachusetts 02139 (United States); Mathews, Jay; Warrender, Jeffrey M. [Benet Laboratories, U.S. Army ARDEC, Watervliet, New York 12189 (United States)] [Benet Laboratories, U.S. Army ARDEC, Watervliet, New York 12189 (United States)

    2013-09-28T23:59:59.000Z

    We investigate the possibility of creating an intermediate band semiconductor by supersaturating Si with a range of transition metals (Au, Co, Cr, Cu, Fe, Pd, Pt, W, and Zn) using ion implantation followed by pulsed laser melting (PLM). Structural characterization shows evidence of either surface segregation or cellular breakdown in all transition metals investigated, preventing the formation of high supersaturations. However, concentration-depth profiling reveals that regions of Si supersaturated with Au and Zn are formed below the regions of cellular breakdown. Fits to the concentration-depth profile are used to estimate the diffusive speeds, v{sub D,} of Au and Zn, and put lower bounds on v{sub D} of the other metals ranging from 10{sup 2} to 10{sup 4} m/s. Knowledge of v{sub D} is used to tailor the irradiation conditions and synthesize single-crystal Si supersaturated with 10{sup 19} Au/cm{sup 3} without cellular breakdown. Values of v{sub D} are compared to those for other elements in Si. Two independent thermophysical properties, the solute diffusivity at the melting temperature, D{sub s}(T{sub m}), and the equilibrium partition coefficient, k{sub e}, are shown to simultaneously affect v{sub D}. We demonstrate a correlation between v{sub D} and the ratio D{sub s}(T{sub m})/k{sub e}{sup 0.67}, which is exhibited for Group III, IV, and V solutes but not for the transition metals investigated. Nevertheless, comparison with experimental results suggests that D{sub s}(T{sub m})/k{sub e}{sup 0.67} might serve as a metric for evaluating the potential to supersaturate Si with transition metals by PLM.

  16. Some intriguing properties of Tukey's half-space depth

    E-Print Network [OSTI]

    Dutta, Subhajit; Chaudhuri, Probal; 10.3150/10-BEJ322

    2012-01-01T23:59:59.000Z

    For multivariate data, Tukey's half-space depth is one of the most popular depth functions available in the literature. It is conceptually simple and satisfies several desirable properties of depth functions. The Tukey median, the multivariate median associated with the half-space depth, is also a well-known measure of center for multivariate data with several interesting properties. In this article, we derive and investigate some interesting properties of half-space depth and its associated multivariate median. These properties, some of which are counterintuitive, have important statistical consequences in multivariate analysis. We also investigate a natural extension of Tukey's half-space depth and the related median for probability distributions on any Banach space (which may be finite- or infinite-dimensional) and prove some results that demonstrate anomalous behavior of half-space depth in infinite-dimensional spaces.

  17. Transitioning to a Lean Enterprise: A Guide for Leaders, Volume III, Roadmap Explorations

    E-Print Network [OSTI]

    Bozdogan, Kirk

    2000-01-01T23:59:59.000Z

    Volume III of this guide may be used as an in-depth reference source for acquiring deep knowledge about many of the aspects of transitioning to lean. Lean change agents and lean implementation leaders should find this ...

  18. Hyperspectral Aerosol Optical Depths from TCAP Flights

    SciTech Connect (OSTI)

    Shinozuka, Yohei; Johnson, Roy R.; Flynn, Connor J.; Russell, P. B.; Schmid, Beat; Redemann, Jens; Dunagan, Stephen; Kluzek, Celine D.; Hubbe, John M.; Segal-Rosenheimer, Michal; Livingston, J. M.; Eck, T.; Wagener, Richard; Gregory, L.; Chand, Duli; Berg, Larry K.; Rogers, Ray; Ferrare, R. A.; Hair, John; Hostetler, Chris A.; Burton, S. P.

    2013-11-13T23:59:59.000Z

    4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research), the world’s first hyperspectral airborne tracking sunphotometer, acquired aerosol optical depths (AOD) at 1 Hz during all July 2012 flights of the Two Column Aerosol Project (TCAP). Root-mean square differences from AERONET ground-based observations were 0.01 at wavelengths between 500-1020 nm, 0.02 at 380 and 1640 nm and 0.03 at 440 nm in four clear-sky fly-over events, and similar in ground side-by-side comparisons. Changes in the above-aircraft AOD across 3-km-deep spirals were typically consistent with integrals of coincident in situ (on DOE Gulfstream 1 with 4STAR) and lidar (on NASA B200) extinction measurements within 0.01, 0.03, 0.01, 0.02, 0.02, 0.02 at 355, 450, 532, 550, 700, 1064 nm, respectively, despite atmospheric variations and combined measurement uncertainties. Finer vertical differentials of the 4STAR measurements matched the in situ ambient extinction profile within 14% for one homogeneous column. For the AOD observed between 350-1660 nm, excluding strong water vapor and oxygen absorption bands, estimated uncertainties were ~0.01 and dominated by (then) unpredictable throughput changes, up to +/-0.8%, of the fiber optic rotary joint. The favorable intercomparisons herald 4STAR’s spatially-resolved high-frequency hyperspectral products as a reliable tool for climate studies and satellite validation.

  19. Depth of manual dismantling analysis: A cost–benefit approach

    SciTech Connect (OSTI)

    Achillas, Ch., E-mail: c.achillas@ihu.edu.gr [School of Economics and Business Administration, International Hellenic University, 14th km Thessaloniki-Moudania, 57001 Thermi (Greece); Aidonis, D. [Department of Logistics, Alexander Technological Educational Institute, Branch of Katerini, 60100 Katerini (Greece); Vlachokostas, Ch.; Karagiannidis, A.; Moussiopoulos, N.; Loulos, V. [Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Aristotle University, Thessaloniki, Box 483, 54124 Thessaloniki (Greece)

    2013-04-15T23:59:59.000Z

    Highlights: ? A mathematical modeling tool for OEMs. ? The tool can be used by OEMs, recyclers of electr(on)ic equipment or WEEE management systems’ regulators. ? The tool makes use of cost–benefit analysis in order to determine the optimal depth of product disassembly. ? The reusable materials and the quantity of metals and plastics recycled can be quantified in an easy-to-comprehend manner. - Abstract: This paper presents a decision support tool for manufacturers and recyclers towards end-of-life strategies for waste electrical and electronic equipment. A mathematical formulation based on the cost benefit analysis concept is herein analytically described in order to determine the parts and/or components of an obsolete product that should be either non-destructively recovered for reuse or be recycled. The framework optimally determines the depth of disassembly for a given product, taking into account economic considerations. On this basis, it embeds all relevant cost elements to be included in the decision-making process, such as recovered materials and (depreciated) parts/components, labor costs, energy consumption, equipment depreciation, quality control and warehousing. This tool can be part of the strategic decision-making process in order to maximize profitability or minimize end-of-life management costs. A case study to demonstrate the models’ applicability is presented for a typical electronic product in terms of structure and material composition. Taking into account the market values of the pilot product’s components, the manual disassembly is proven profitable with the marginal revenues from recovered reusable materials to be estimated at 2.93–23.06 €, depending on the level of disassembly.

  20. Asynchronous-Transition HMM 

    E-Print Network [OSTI]

    Matsuda, Shigeki; Nakai, Mitsuru; Shimodaira, Hiroshi; Sagayama, Shigeki

    We propose a new class of hidden Markov model (HMM) called asynchronous-transition HMM (AT-HMM). Opposed to conventional HMMs where hidden state transition occurs simultaneously to all features, the new class of HMM allows state transitions...

  1. Exploration of R2XM2 (R=Sc, Y, Ti, Zr, Hf, rare earth; X=main group element; M=transition metal, Si, Ge): Structural Motifs, the novel Compound Gd2AlGe2 and Analysis of the U3Si2 and Zr3Al2 Structure Types

    SciTech Connect (OSTI)

    Sean William McWhorter

    2006-05-01T23:59:59.000Z

    In the process of exploring and understanding the influence of crystal structure on the system of compounds with the composition Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} several new compounds were synthesized with different crystal structures, but similar structural features. In Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4}, the main feature of interest is the magnetocaloric effect (MCE), which allows the material to be useful in magnetic refrigeration applications. The MCE is based on the magnetic interactions of the Gd atoms in the crystal structure, which varies with x (the amount of Si in the compound). The crystal structure of Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} can be thought of as being formed from two 3{sup 2}434 nets of Gd atoms, with additional Gd atoms in the cubic voids and Si/Ge atoms in the trigonal prismatic voids. Attempts were made to substitute nonmagnetic atoms for magnetic Gd using In, Mg and Al. Gd{sub 2}MgGe{sub 2} and Gd{sub 2}InGe{sub 2} both possess the same 3{sup 2}434 nets of Gd atoms as Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4}, but these nets are connected differently, forming the Mo{sub 2}FeB{sub 2} crystal structure. A search of the literature revealed that compounds with the composition R{sub 2}XM{sub 2} (R=Sc, Y, Ti, Zr, Hf, rare earth; X=main group element; M=transition metal, Si, Ge) crystallize in one of four crystal structures: the Mo{sub 2}FeB{sub 2}, Zr{sub 3}Al{sub 2}, Mn{sub 2}AlB{sub 2} and W{sub 2}CoB{sub 2} crystal structures. These crystal structures are described, and the relationships between them are highlighted. Gd{sub 2}AlGe{sub 2} forms an entirely new crystal structure, and the details of its synthesis and characterization are given. Electronic structure calculations are performed to understand the nature of bonding in this compound and how electrons can be accounted for. A series of electronic structure calculations were performed on models with the U{sub 3}Si{sub 2} and Zr{sub 3}Al{sub 2} structures, using Zr and A1 as the building blocks. The starting point for these models was the U{sub 3}Si{sub 2} structure, and models were created to simulate the transition from the idealized U{sub 3}Si{sub 2} structure to the distorted Zr{sub 3}Al{sub 2} structure. Analysis of the band structures of the models has shown that the transition from the U{sub 3}Si{sub 2} structure to the Zr{sub 3}Al{sub 2} structure lifts degeneracies along the {Lambda} {yields} Z direction, indicating a Peierls-type mechanism for the displacement occurring in the positions of the Zr atoms.

  2. Method and apparatus of prefetching streams of varying prefetch depth

    DOE Patents [OSTI]

    Gara, Alan (Mount Kisco, NY); Ohmacht, Martin (Yorktown Heights, NY); Salapura, Valentina (Chappaqua, NY); Sugavanam, Krishnan (Mahopac, NY); Hoenicke, Dirk (Seebruck-Seeon, DE)

    2012-01-24T23:59:59.000Z

    Method and apparatus of prefetching streams of varying prefetch depth dynamically changes the depth of prefetching so that the number of multiple streams as well as the hit rate of a single stream are optimized. The method and apparatus in one aspect monitor a plurality of load requests from a processing unit for data in a prefetch buffer, determine an access pattern associated with the plurality of load requests and adjust a prefetch depth according to the access pattern.

  3. A Dianionic Phosphorane Intermediate and Transition States in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of this debate centers around the roles of the conserved residues, structures of the transition state or states, the possibility of a stable intermediate, and the charge and...

  4. A Dianionic Phosphorane Intermediate and Transition States in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    reactions requires that the details of the reaction mechanisms (e.g. reaction paths, transition state stabilization and structure, etc.) that leads to their remarkable rates in...

  5. APOSTLE: 11 TRANSIT OBSERVATIONS OF TrES-3b

    SciTech Connect (OSTI)

    Kundurthy, P.; Becker, A. C.; Agol, E.; Barnes, R.; Williams, B. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States)] [Astronomy Department, University of Washington, Seattle, WA 98195 (United States)

    2013-02-10T23:59:59.000Z

    The Apache Point Survey of Transit Lightcurves of Exoplanets (APOSTLE) observed 11 transits of TrES-3b over two years in order to constrain system parameters and look for transit timing and depth variations. We describe an updated analysis protocol for APOSTLE data, including the reduction pipeline, transit model, and Markov Chain Monte Carlo analyzer. Our estimates of the system parameters for TrES-3b are consistent with previous estimates to within the 2{sigma} confidence level. We improved the errors (by 10%-30%) on system parameters such as the orbital inclination (i {sub orb}), impact parameter (b), and stellar density ({rho}{sub *}) compared to previous measurements. The near-grazing nature of the system, and incomplete sampling of some transits, limited our ability to place reliable uncertainties on individual transit depths and hence we do not report strong evidence for variability. Our analysis of the transit timing data shows no evidence for transit timing variations and our timing measurements are able to rule out super-Earth and gas giant companions in low-order mean motion resonance with TrES-3b.

  6. Conformational Transitions in Molecular Systems

    E-Print Network [OSTI]

    Michael Bachmann; Wolfhard Janke

    2009-02-17T23:59:59.000Z

    Proteins are the "work horses" in biological systems. In almost all functions specific proteins are involved. They control molecular transport processes, stabilize the cell structure, enzymatically catalyze chemical reactions; others act as molecular motors in the complex machinery of molecular synthetization processes. Due to their significance, misfolds and malfunctions of proteins typically entail disastrous diseases, such as Alzheimer's disease and bovine spongiform encephalopathy (BSE). Therefore, the understanding of the trinity of amino acid composition, geometric structure, and biological function is one of the most essential challenges for the natural sciences. Here, we glance at conformational transitions accompanying the structure formation in protein folding processes.

  7. Advanced Technology Vehicle Lab Benchmarking - Level 2 (in-depth...

    Broader source: Energy.gov (indexed) [DOE]

    Other Institutions 13 J1711 HEV & PHEV test procedures In-depth Benchmarking DOE technology evaluation * DOE requests * National Lab requests AVTA (Advanced Vehicle Testing...

  8. aes depth profile: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    California eScholarship Repository Summary: al. , 2005). The vertical profile of wind speed over the seavertical directionality Depth-dependence of wind speedVertical...

  9. Safeguards and security issues during facility transition

    SciTech Connect (OSTI)

    Smith, M.R. [USDOE Office of Safeguards and Security, Washington, DC (United States); Zack, N.R. [Los Alamos National Lab., NM (United States). Safeguards Systems Group

    1993-12-31T23:59:59.000Z

    The transition of Department of Energy (DOE) production facilities to those destined for decontamination and decommissioning (D and D) must consider traditional safeguards and security requirements governing nuclear materials. Current DOE safeguards and security policy establishes specific requirements for the removal of facilities and waste from safeguards. However, the current physical security policy does not differentiate the protection of waste from usable materials. Other transition issues include: access of uncleared individuals, positioning security zones, nuclear material holdup, accounting for difficult-to-measure materials, inventory difference and resolution, and radiological/toxicological sabotage. Safeguards and security goals for facility transitioning must provide a workable, efficient and cost-effective system for accounting and protecting nuclear material. In depth protection strategies utilizing combinations of safeguards and security systems should be developed to meet these goals.

  10. Variability of Disk Emission in Pre-Main Sequence and Related Stars. III. Exploring Structural Changes in the Pre-transitional Disk in HD 169142

    E-Print Network [OSTI]

    Wagner, Kevin R; Grady, Carol A; Whitney, Barbara A; Swearingen, Jeremy R; Champney, Elizabeth H; Johnson, Alexa N; Werren, Chelsea; Russell, Ray W; Schneider, Glenn H; Momose, Munetake; Muto, Takayuki; Inoue, Akio K; Lauroesch, James T; Brown, Alexander; Fukagawa, Misato; Currie, Thayne M; Hornbeck, Jeremy; Wisniewski, John P; Woodgate, Bruce E

    2014-01-01T23:59:59.000Z

    We present near-IR and far-UV observations of the pre-transitional (gapped) disk in HD 169142 using NASA's Infrared Telescope Facility and Hubble Space Telescope. The combination of our data along with existing data sets into the broadband spectral energy distribution reveals variability of up to 45% between ~1.5-10 {\\mu}m over a maximum timescale of 10 years. All observations known to us separate into two distinct states corresponding to a high near-IR state in the pre-2000 epoch and a low state in the post-2000 epoch, indicating activity within the <1 AU region of the disk. Through analysis of the Pa {\\beta} and Br {\\gamma} lines in our data we derive a mass accretion rate in May 2013 of (1.5 - 2.7) x 10^-9 Msun/yr. We present a theoretical modeling analysis of the disk in HD 169142 using Monte-Carlo radiative transfer simulation software to explore the conditions and perhaps signs of planetary formation in our collection of 24 years of observations. We find that shifting the outer edge (r = 0.3 AU) of t...

  11. Electrode immersion depth determination and control in electroslag remelting furnace

    DOE Patents [OSTI]

    Melgaard, David K. (Albuquerque, NM); Beaman, Joseph J. (Austin, TX); Shelmidine, Gregory J. (Tijeras, NM)

    2007-02-20T23:59:59.000Z

    An apparatus and method for controlling an electroslag remelting furnace comprising adjusting electrode drive speed by an amount proportional to a difference between a metric of electrode immersion and a set point, monitoring impedance or voltage, and calculating the metric of electrode immersion depth based upon a predetermined characterization of electrode immersion depth as a function of impedance or voltage.

  12. Depth Camera based Localization and Navigation for Indoor Mobile Robots

    E-Print Network [OSTI]

    McLaren, Bruce Martin

    . 1. Snapshot of depth image processing: On the left, the complete 3D point cloud is shown in white cloud by sampling points from the depth image, and classifying local grouped sets of points as belonging. The full sampled point cloud (consisting of both plane filtered as well as outlier points) is processed

  13. Imaging wave-penetrable objects in a finite depth ocean

    E-Print Network [OSTI]

    Zou, Jun

    Imaging wave-penetrable objects in a finite depth ocean Keji Liu Yongzhi Xu Jun Zou Abstract. We- penetrable inhomogeneous medium in a 3D finite depth ocean. The method is based on a scat- tering analysis extend the direct sampling method proposed in [13] to image a wave- penetrable inhomogeneous medium

  14. A Depth Space Approach to Human-Robot Collision Avoidance

    E-Print Network [OSTI]

    De Luca, Alessandro

    A Depth Space Approach to Human-Robot Collision Avoidance Fabrizio Flacco Torsten Kr is presented for safe human-robot coexistence. The main contribution is a fast method to evaluate distances between the robot and possibly moving obstacles (including humans), based on the concept of depth space

  15. The chiral transition in two-flavor QCD

    E-Print Network [OSTI]

    M. D'Elia; A. Di Giacomo; C. Pica

    2005-10-03T23:59:59.000Z

    QCD with N_f=2 is a specially interesting system to investigate the chiral transition. The order of the transition has still not been established. We report the results of an in-depth numerical investigation performed with staggered fermions on lattices with L_t=4 and L_s=12,16,20,24,32 and quark masses am_q ranging from 0.01335 to 0.307036. Using finite-size techniques we compare the scaling behavior of a number of thermodynamical susceptibilities with the expectations of O(4) and O(2) universality classes. Clear disagreement is observed. Indications of a first order transition are found.

  16. Can fusion coefficients be calculated from the depth rule ?

    E-Print Network [OSTI]

    A. N. Kirillov; P. Mathieu; D. Senechal; M. Walton

    1992-09-28T23:59:59.000Z

    The depth rule is a level truncation of tensor product coefficients expected to be sufficient for the evaluation of fusion coefficients. We reformulate the depth rule in a precise way, and show how, in principle, it can be used to calculate fusion coefficients. However, we argue that the computation of the depth itself, in terms of which the constraints on tensor product coefficients is formulated, is problematic. Indeed, the elements of the basis of states convenient for calculating tensor product coefficients do not have a well-defined depth! We proceed by showing how one can calculate the depth in an `approximate' way and derive accurate lower bounds for the minimum level at which a coupling appears. It turns out that this method yields exact results for $\\widehat{su}(3)$ and constitutes an efficient and simple algorithm for computing $\\widehat{su}(3)$ fusion coefficients.

  17. Transition from galactic to extragalactic cosmic rays

    E-Print Network [OSTI]

    V. Berezinsky

    2007-10-20T23:59:59.000Z

    The transition from galactic to extragalactic cosmic rays is discussed. One of critical indications for transition is given by the Standard Model of Galactic cosmic rays, according to which the maximum energy of acceleration for iron nuclei is of order of $E_{\\rm Fe}^{\\rm max} \\approx 1\\times 10^{17}$ eV. At $E > E_{\\rm Fe}^{\\rm max}$ the spectrum is predicted to be very steep and thus the Standard Model favours the transition at energy not much higher than $E_{\\rm Fe}^{\\rm max}$. As observations are concerned there are two signatures of transition: change of energy spectra and elongation rate (depth of shower maximum in the atmosphere $X_{\\rm max}$ as function of energy). Three models of transition are discussed: dip-based model, mixed composition model and ankle model. In the latter model the transition occurs at the observed spectral feature, ankle, which starts at $E_a \\approx 1\\times 10^{19}$ eV and is characterised by change of mass compostion from galactic iron to extragalactic protons. In the dip model the transition occures at the second knee observed at energy $(4 -8)\\times 10^{17}$ eV and is characterised by change of mass composition from galactic iron to extragalactic protons. The mixed composition model describes transition at $E \\sim 3\\times 10^{18}$ eV with mass composition changing from galactic iron to extragactic mixed composition of different nuclei. These models are confronted with observational data on spectra and elongation rates from different experiments, including Auger.

  18. Gas turbine combustor transition

    DOE Patents [OSTI]

    Coslow, Billy Joe (Winter Park, FL); Whidden, Graydon Lane (Great Blue, CT)

    1999-01-01T23:59:59.000Z

    A method of converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit.

  19. Gas turbine combustor transition

    DOE Patents [OSTI]

    Coslow, B.J.; Whidden, G.L.

    1999-05-25T23:59:59.000Z

    A method is described for converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit. 7 figs.

  20. Superconducting Transitions in Wire Network under Spatially Modulated Magnetic Field

    E-Print Network [OSTI]

    Katsumoto, Shingo

    The nature of phase transition in artificially structured superconducting systems such as superconducting artificially structured superconducting systems]. Introduction of the checkerboard field with amplitude #12; to the ¼ 1=2 case lifts the double degeneracy

  1. Geometry-Based Sampling of Conformational Transitions in Proteins

    E-Print Network [OSTI]

    de Groot, Bert

    Structure Article Geometry-Based Sampling of Conformational Transitions in Proteins Daniel Seeliger of the binding site when using a holo structure, or by not identifying the correct binding pose when using an apo

  2. Microphysical and Dynamical Influences on Cirrus Cloud Optical Depth Distributions

    SciTech Connect (OSTI)

    Kay, J.; Baker, M.; Hegg, D.

    2005-03-18T23:59:59.000Z

    Cirrus cloud inhomogeneity occurs at scales greater than the cirrus radiative smoothing scale ({approx}100 m), but less than typical global climate model (GCM) resolutions ({approx}300 km). Therefore, calculating cirrus radiative impacts in GCMs requires an optical depth distribution parameterization. Radiative transfer calculations are sensitive to optical depth distribution assumptions (Fu et al. 2000; Carlin et al. 2002). Using raman lidar observations, we quantify cirrus timescales and optical depth distributions at the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site in Lamont, OK (USA). We demonstrate the sensitivity of outgoing longwave radiation (OLR) calculations to assumed optical depth distributions and to the temporal resolution of optical depth measurements. Recent work has highlighted the importance of dynamics and nucleation for cirrus evolution (Haag and Karcher 2004; Karcher and Strom 2003). We need to understand the main controls on cirrus optical depth distributions to incorporate cirrus variability into model radiative transfer calculations. With an explicit ice microphysics parcel model, we aim to understand the influence of ice nucleation mechanism and imposed dynamics on cirrus optical depth distributions.

  3. Glass Transition in Confined Geometry

    E-Print Network [OSTI]

    Simon Lang; Vitalie Botan; Martin Oettel; David Hajnal; Thomas Franosch; Rolf Schilling

    2010-08-23T23:59:59.000Z

    Extending mode-coupling theory, we elaborate a microscopic theory for the glass transition of liquids confined between two parallel flat hard walls. The theory contains the standard MCT equations in bulk and in two dimensions as limiting cases and requires as input solely the equilibrium density profile and the structure factors of the fluid in confinement. We evaluate the phase diagram as a function of the distance of the plates for the case of a hard sphere fluid and obtain an oscillatory behavior of the glass transtion line as a result of the structural changes related to layering.

  4. Tips for Transition

    E-Print Network [OSTI]

    Kellems, Ryan Owen; Morningstar, Mary E.

    2010-01-01T23:59:59.000Z

    The article focuses on the best practices solicited by the Division on Career Development & Transition (DCDT) for the student to adult life transition planning for youth with disabilities. The DCDT launched an effort to identify field...

  5. Diagonal-transition quantum cascade detector

    SciTech Connect (OSTI)

    Reininger, Peter, E-mail: peter.reininger@tuwien.ac.at; Schwarz, Benedikt; Detz, Hermann; MacFarland, Don; Zederbauer, Tobias; Andrews, Aaron Maxwell; Schrenk, Werner; Strasser, Gottfried [Institute for Solid State Electronics and Center for Micro- and Nanostructures, Vienna University of Technology, Vienna (Austria); Baumgartner, Oskar; Kosina, Hans [Institute for Microelectronics, Vienna University of Technology, Vienna (Austria)

    2014-09-01T23:59:59.000Z

    We demonstrate the concept of diagonal transitions for quantum cascade detectors (QCD). Different to standard, vertical QCDs, here the active transition takes place between two energy levels in adjacent wells. Such a scheme has versatile advantages. Diagonal transitions generally yield a higher extraction efficiency and a higher resistance than vertical transitions. This leads to an improved overall performance, although the absorption strength of the active transition is smaller. Since the extraction is not based on resonant tunneling, the design is more robust, with respect to deviations from the nominal structure. In a first approach, a peak responsivity of 16.9?mA/W could be achieved, which is an improvement to the highest shown responsivity of a QCD for a wavelength of 8??m at room-temperature by almost an order of magnitude.

  6. Vibrational fine structure in the valence ionizations of transition-metal hexacarbonyls: new experimental indication of metal-to-carbonyl. pi. bonding

    SciTech Connect (OSTI)

    Hubbard, J.L.; Lichtenberger, D.L.

    1982-04-21T23:59:59.000Z

    The first observations of metal-carbon vibrational structure in photoionization bands are reported. Attention is focused on the predominantly metal d ionizations of M(CO)/sub 6/ (M = Cr, Mo, and W), and the methods for obtaining high resolution and very high signal-to-noise He I ionization data are detailed. The /sup 2/T/sub 2g/ ionization band of Cr(CO)/sub 6/ and the spin-orbit split /sup 2/E'' and /sup 2/U' bands of W(CO)/sub 6/ show distinct vibrational progressions which correspond to the totally symmetric (a/sub 1g/) metal-carbon stretching mode in the positive ion states. The metal-carbon stretching frequencies are found to be significantly less in the positive ion states than in the ground states, indicating a reduction of metal-carbon bond order upon the loss of a t/sub 2g/ electron. Evaluation of the vibrational progressions shows that the metal-carbon bond length increases on the order of 0.10 A upon t/sub 2g/ ionization in the case of W(CO)/sub 6/ and about 0.14 A in the case of Cr(CO)/sub 6/. In addition, the beginning of a short progression in the a/sub 1g/ carbon-oxygen stretching mode is observed in the Mo(CO)/sub 6/ spectrum and is clearly seen in the W(CO)/sub 6/ spectrum. All of these observations show that removal of an electron from the predominantly metal t/sub 2g/ orbitals, which are strictly ..pi.. symmetry with respect to the carbonyls, substantially weakens the metal-to-carbonyl bond. 9 figures, 2 tables.

  7. One-particle transition.

    E-Print Network [OSTI]

    Adler, Joan

    One-particle di#11;usional model to mimic some properties of glass transition. Sorkin A.V., Ivanov #15; Computer studies of glass transition #15; Model and simulations #15; Results #15; Conclusions 2 #12; Introduction In recent time many properties of glass transitions have been investigated

  8. Light Rail Transit Strengthening

    E-Print Network [OSTI]

    Minnesota, University of

    Light Rail Transit Improving mobility Easing congestion Strengthening our communities Central Corridor Communicating to the Public During Major Construction May 25, 2011 #12;2 Light Rail Transit;Light Rail Transit Central Corridor Route and Stations 3 · 18 new stations · 9.8 miles of new double

  9. Variations in microbial community composition through two soil depth profiles

    E-Print Network [OSTI]

    Fierer, Noah

    35% of the total quantity of microbial biomass found in the top 2 m of soil is found below a depth: Microbial diversity; Phospholipid fatty acid; Soil profile; Community composition; Microbial biomass 1

  10. Next Generation Nuclear Plant Defense-in-Depth Approach

    SciTech Connect (OSTI)

    Edward G. Wallace; Karl N. Fleming; Edward M. Burns

    2009-12-01T23:59:59.000Z

    The purpose of this paper is to (1) document the definition of defense-in-depth and the pproach that will be used to assure that its principles are satisfied for the NGNP project and (2) identify the specific questions proposed for preapplication discussions with the NRC. Defense-in-depth is a safety philosophy in which multiple lines of defense and conservative design and evaluation methods are applied to assure the safety of the public. The philosophy is also intended to deliver a design that is tolerant to uncertainties in knowledge of plant behavior, component reliability or operator performance that might compromise safety. This paper includes a review of the regulatory foundation for defense-in-depth, a definition of defense-in-depth that is appropriate for advanced reactor designs based on High Temperature Gas-cooled Reactor (HTGR) technology, and an explanation of how this safety philosophy is achieved in the NGNP.

  11. aerosol optical depths: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AERONET, AVHRR and 3 MODIS 4 A. Hauser, D. Oesch have been used to 9 retrieve the spatial distribution of aerosol optical depth for 10 central Europe. At eight AERONET sites,...

  12. aerosol optical depth: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AERONET, AVHRR and 3 MODIS 4 A. Hauser, D. Oesch have been used to 9 retrieve the spatial distribution of aerosol optical depth for 10 central Europe. At eight AERONET sites,...

  13. Method and apparatus to measure the depth of skin burns

    DOE Patents [OSTI]

    Dickey, Fred M. (Albuquerque, NM); Holswade, Scott C. (Albuquerque, NM)

    2002-01-01T23:59:59.000Z

    A new device for measuring the depth of surface tissue burns based on the rate at which the skin temperature responds to a sudden differential temperature stimulus. This technique can be performed without physical contact with the burned tissue. In one implementation, time-dependent surface temperature data is taken from subsequent frames of a video signal from an infrared-sensitive video camera. When a thermal transient is created, e.g., by turning off a heat lamp directed at the skin surface, the following time-dependent surface temperature data can be used to determine the skin burn depth. Imaging and non-imaging versions of this device can be implemented, thereby enabling laboratory-quality skin burn depth imagers for hospitals as well as hand-held skin burn depth sensors the size of a small pocket flashlight for field use and triage.

  14. Case depth verification of hardened samples with Barkhausen noise sweeps

    SciTech Connect (OSTI)

    Santa-aho, Suvi; Vippola, Minnamari; Lepistö, Toivo [Tampere University of Technology, Department of Materials Science, P.O. Box 589, 33101 Tampere (Finland); Hakanen, Merja [Stresstech Oy, Tikkutehtaantie 1, 40800 Vaajakoski (Finland); Sorsa, Aki; Leiviskä, Kauko [University of Oulu, Control Engineering Laboratory, P.O. Box 4300, FIN-90014 University of Oulu (Finland)

    2014-02-18T23:59:59.000Z

    An interesting topic of recent Barkhausen noise (BN) method studies is the application of the method to case depth evaluation of hardened components. The utilization of BN method for this purpose is based on the difference in the magnetic properties between the hardened case and the soft core. Thus, the detection of case depth with BN can be achieved. The measurements typically have been carried out by using low magnetizing frequencies which have deeper penetration to the ferromagnetic samples than the conventional BN measurement. However, the penetration depth is limited due to eddy current damping of the signal. We introduce here a newly found sweep measurement concept for the case depth evaluation. In this study sweep measurements were carried out with various magnetizing frequencies and magnetizing voltages to detect the effect of different frequency and voltage and their correspondence to the actual case depth values verified from destructive characterization. Also a BN measurement device that has an implemented sweep analysis option was utilised. The samples were either induction or case-hardened samples and sample geometry contained both rod samples and gear axle samples with different case depth values. Samples were also further characterized with Xray diffraction to study the residual stress state of the surface. The detailed data processing revealed that also other calculated features than the maximum slope division of the 1st derivative of the BN signal could hold the information about the case depth value of the samples. The sweep method was able to arrange the axles into correct order according to the case depth value even though the axles were used.

  15. Burial depth and stratigraphic controls on shale diagenesis

    E-Print Network [OSTI]

    Moore, David Wesley

    1983-01-01T23:59:59.000Z

    - layer illite/smectite in Gulf Coast sediments at a shallow depth is a randomly-interstratified illite/smectite with proportions of 804 smectite and 20% illite (Perry and Hower, 1972). Many authors (Dunoyer de Segonzac, 1970; Perry and Hower, 1970..., 1972; Hower et al. , 1976; Foscolos and Kodama, 1974) have noted the increase in illite with concurrent decrease of smectite in the mixed-layer illite/smec- tite with increasing depth and temperature. The conversion of smectite into illite resulting...

  16. Colour videos with depth : acquisition, processing and evaluation

    E-Print Network [OSTI]

    Richardt, Christian

    2012-03-06T23:59:59.000Z

    . Declaration This dissertation is the result of my own work and includes nothing which is the outcome of work done in collaboration except where specifically indicated in the text. This dissertation does not exceed the regulation length of 60 000 words... -step pipeline that aligns the video streams, efficiently removes and fills invalid and noisy geometry, and finally uses a spatiotemporal filter to increase the spatial resolution of the depth data and strongly reduce depth measurement noise. I show...

  17. Structure of ?-Alumina: Toward The Atomic Level Understanding...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    -Alumina: Toward The Atomic Level Understanding Of Transition Alumina Phases. Structure of -Alumina: Toward The Atomic Level Understanding Of Transition Alumina Phases....

  18. PHYSICAL REVIEW E 84, 051103 (2011) Microscopic theory of the jamming transition of harmonic spheres

    E-Print Network [OSTI]

    Berthier, Ludovic

    transition and its relation to the phenomenon of the glass transition observed in atomic liquids. DOI: 10 for emulsions and foams [4]. However, while the structure of dense atomic liquids is by now well understood to solid transition observed in athermal systems shares similarities with the glass transition

  19. The chiral transition as an Anderson transition

    E-Print Network [OSTI]

    Matteo Giordano; Sandor D. Katz; Tamas G. Kovacs; Ferenc Pittler

    2014-10-31T23:59:59.000Z

    At low temperature the low-lying QCD Dirac spectrum obeys random matrix statistics. Recently we found that above $T_{c}$ the lowest part of the spectrum consists of localized modes that obey Poisson statistics. An interesting implication of this is that as the system crosses $T_{c}$ from above, the spectral statistics at $\\lambda=0$ changes from Poisson to random matrix. Here we study this transition and its possible implications for the finite temperature transition of QCD-like theories.

  20. Heat conduction through a trapped solid: effect of structural changes on thermal conductance

    E-Print Network [OSTI]

    Debasish Chaudhuri; Abhishek Chaudhuri; Surajit Sengupta

    2007-03-20T23:59:59.000Z

    We study the conduction of heat across a narrow solid strip trapped by an external potential and in contact with its own liquid. Structural changes, consisting of addition and deletion of crystal layers in the trapped solid, are produced by altering the depth of the confining potential. Nonequilibrium molecular dynamics simulations and, wherever possible, simple analytical calculations are used to obtain the thermal resistance in the liquid, solid and interfacial regions (Kapitza or contact resistance). We show that these layering transitions are accompanied by sharp jumps in the contact thermal resistance. Dislocations, if present, are shown to increase the thermal resistance of the strip drastically.

  1. Superconducting coherence length and magnetic penetration depth of a p-wave holographic superconductor

    SciTech Connect (OSTI)

    Zeng Huabi; Fan Zheyong [Department of Physics, Nanjing University, Nanjing 210093 (China); Zong Hongshi [Department of Physics, Nanjing University, Nanjing 210093 (China); Joint Center for Particle, Nuclear Physics and Cosmology, Nanjing 210093 (China)

    2010-05-15T23:59:59.000Z

    A classical SU(2) Einstein-Yang-Mills theory in (3+1)-dimensional anti-de Sitter spacetime is believed to be dual to a p-wave superconductor in (2+1)-dimensional flat spacetime. In order to calculate the superconducting coherence length {xi} of the holographic superconductor near the superconducting phase transition point, we make a perturbative study of the gravity theory analytically. The superconducting coherence length {xi} is found to be proportional to (1-T/T{sub c}){sup -1/2} near the critical temperature T{sub c}. We also obtain the magnetic penetration depth {lambda}{proportional_to}(T{sub c}-T){sup 1/2} by adding a small external homogeneous magnetic field. The results agree with the Ginzburg-Landau theory.

  2. Superconducting Coherence Length and Magnetic Penetration Depth of a p-wave Holographic Superconductor

    E-Print Network [OSTI]

    Hua-Bi Zeng; Zhe-Yong Fan; Hong-Shi Zong

    2010-04-16T23:59:59.000Z

    A classical SU(2) Einstein-Yang-Mills theory in 3+1 dimensional anti-de Sitter spacetime is believed to be dual to a p-wave superconductor in 2+1 dimensional flat spacetime. In order to calculate the superconductiong coherence length $\\xi$ of the holographic superconductor near the superconducting phase transition point, we study the perturbation of the gravity theory analytically. The superconductiong coherence length $\\xi$ is found to be proportional to $(1-T/T_c)^{-1/2}$ near the critical temperature $T_c$. We also obtain the magnetic penetration depth $\\lambda\\propto(T_c-T)^{1/2}$ by adding a small external homogeneous magnetic field. The results agree with the Ginzburg-Landau theory.

  3. Measuring depth profiles of residual stress with Raman spectroscopy

    SciTech Connect (OSTI)

    Enloe, W.S.; Sparks, R.G.; Paesler, M.A.

    1988-12-01T23:59:59.000Z

    Knowledge of the variation of residual stress is a very important factor in understanding the properties of machined surfaces. The nature of the residual stress can determine a part`s susceptibility to wear deformation, and cracking. Raman spectroscopy is known to be a very useful technique for measuring residual stress in many materials. These measurements are routinely made with a lateral resolution of 1{mu}m and an accuracy of 0.1 kbar. The variation of stress with depth; however, has not received much attention in the past. A novel technique has been developed that allows quantitative measurement of the variation of the residual stress with depth with an accuracy of 10nm in the z direction. Qualitative techniques for determining whether the stress is varying with depth are presented. It is also demonstrated that when the stress is changing over the volume sampled, errors can be introduced if the variation of the stress with depth is ignored. Computer aided data analysis is used to determine the depth dependence of the residual stress.

  4. Focal depth measurement of scanning helium ion microscope

    SciTech Connect (OSTI)

    Guo, Hongxuan, E-mail: Guo.hongxuan@nims.go.jp [Global Research Center for Environment and Energy based on Nanomaterials Science, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Itoh, Hiroshi; Wang, Chunmei [Active State Technology Research Group, Research Institute of Instrumentation Frontier, National Institute of Advanced Industrial Science and Technology (AIST), 1-1 Umezono 1-Chome, Tsukuba, Ibaraki 305-8568 (Japan); Zhang, Han; Fujita, Daisuke [Nano Characterization Unit, Advanced Key Technologies Division, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan)

    2014-07-14T23:59:59.000Z

    When facing the challenges of critical dimension measurement of complicated nanostructures, such as of the three dimension integrated circuit, characterization of the focal depth of microscopes is important. In this Letter, we developed a method for characterizing the focal depth of a scanning helium ion microscope (HIM) by using an atomic force microscope tip characterizer (ATC). The ATC was tilted in a sample chamber at an angle to the scanning plan. Secondary electron images (SEIs) were obtained at different positions of the ATC. The edge resolution of the SEIs shows the nominal diameters of the helium ion beam at different focal levels. With this method, the nominal shapes of the helium ion beams were obtained with different apertures. Our results show that a small aperture is necessary to get a high spatial resolution and high depth of field images with HIM. This work provides a method for characterizing and improving the performance of HIM.

  5. Hydrogen Transition Infrastructure Analysis

    SciTech Connect (OSTI)

    Melendez, M.; Milbrandt, A.

    2005-05-01T23:59:59.000Z

    Presentation for the 2005 U.S. Department of Energy Hydrogen Program review analyzes the hydrogen infrastructure needed to accommodate a transitional hydrogen fuel cell vehicle demand.

  6. An Investigation of Hydrogen Depth Profiling Using ToF-SIMS....

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Investigation of Hydrogen Depth Profiling Using ToF-SIMS. An Investigation of Hydrogen Depth Profiling Using ToF-SIMS. Abstract: Hydrogen depth distributions in silicon, zinc oxide...

  7. A microwave resonator for limiting depth sensitivity for electron paramagnetic resonance spectroscopy of surfaces

    SciTech Connect (OSTI)

    Sidabras, Jason W.; Varanasi, Shiv K.; Hyde, James S. [Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin 53211 (United States); Mett, Richard R. [Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin 53211 (United States); Department of Physics and Chemistry, Milwaukee School of Engineering, Milwaukee, Wisconsin 53202 (United States); Swarts, Steven G. [Department of Radiation Oncology, University of Florida, Gainesville, Florida, 32610 (United States); Swartz, Harold M. [Department of Radiology, Geisel Medical School at Dartmouth, Hanover, New Hampshire 03755 (United States)

    2014-10-15T23:59:59.000Z

    A microwave Surface Resonator Array (SRA) structure is described for use in Electron Paramagnetic Resonance (EPR) spectroscopy. The SRA has a series of anti-parallel transmission line modes that provides a region of sensitivity equal to the cross-sectional area times its depth sensitivity, which is approximately half the distance between the transmission line centers. It is shown that the quarter-wave twin-lead transmission line can be a useful element for design of microwave resonators at frequencies as high as 10 GHz. The SRA geometry is presented as a novel resonator for use in surface spectroscopy where the region of interest is either surrounded by lossy material, or the spectroscopist wishes to minimize signal from surrounding materials. One such application is in vivo spectroscopy of human finger-nails at X-band (9.5 GHz) to measure ionizing radiation dosages. In order to reduce losses associated with tissues beneath the nail that yield no EPR signal, the SRA structure is designed to limit depth sensitivity to the thickness of the fingernail. Another application, due to the resonator geometry and limited depth penetration, is surface spectroscopy in coating or material science. To test this application, a spectrum of 1.44 ?M of Mg{sup 2+} doped polystyrene 1.1 mm thick on an aluminum surface is obtained. Modeling, design, and simulations were performed using Wolfram Mathematica (Champaign, IL; v. 9.0) and Ansys High Frequency Structure Simulator (HFSS; Canonsburg, PA; v. 15.0). A micro-strip coupling circuit is designed to suppress unwanted modes and provide a balanced impedance transformation to a 50 ? coaxial input. Agreement between simulated and experimental results is shown.

  8. First-principles study of defects and phase transition in UO2...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    defects and phase transition in UO2. First-principles study of defects and phase transition in UO2. Abstract: The electronic properties, structure and phase transformation of UO2...

  9. Low floor mass transit vehicle

    DOE Patents [OSTI]

    Emmons, J. Bruce (Beverly Hills, MI); Blessing, Leonard J. (Rochester, MI)

    2004-02-03T23:59:59.000Z

    A mass transit vehicle includes a frame structure that provides an efficient and economical approach to providing a low floor bus. The inventive frame includes a stiff roof panel and a stiff floor panel. A plurality of generally vertical pillars extend between the roof and floor panels. A unique bracket arrangement is disclosed for connecting the pillars to the panels. Side panels are secured to the pillars and carry the shear stresses on the frame. A unique seating assembly that can be advantageously incorporated into the vehicle taking advantage of the load distributing features of the inventive frame is also disclosed.

  10. The structures of marialite (Me[subscript 6]) and meionite (Me[subscript 93]) in space groups P4[subscript 2]/n and I4/m, and the absence of phase transitions in the scapolite series

    SciTech Connect (OSTI)

    Antao, Sytle M.; Hassan, Ishmael (West Indies) [West Indies; (Calgary)

    2014-05-28T23:59:59.000Z

    The crystal structures of marialite (Me{sub 6}) from Badakhshan, Afghanistan and meionite (Me{sub 93}) from Mt. Vesuvius, Italy were obtained using synchrotron high-resolution powder X-ray diffraction (HRPXRD) data and Rietveld structure refinements. Their structures were refined in space groups I4/m and P42/n, and similar results were obtained. The Me{sub 6} sample has a formula Ca{sub 0.24}Na{sub 3.37}K{sub 0.24}[Al{sub 3.16}Si{sub 8.84}O{sub 24}]Cl{sub 0.84}(CO{sub 3}){sub 0.15}, and its unit-cell parameters are a = 12.047555(7), c = 7.563210(6) {angstrom}, and V = 1097.751(1) {angstrom}{sup 3}. The average (T1-O) distances are 1.599(1) {angstrom} in I4/m and 1.600(2) {angstrom} in P4{sub 2}/n, indicating that the T1 site contains only Si atoms. In P4{sub 2}/n, the average distances of (T2-O) = 1.655(2) and (T3-O) = 1.664(2) {angstrom} are distinct and are not equal to each other. However, the mean (T2,3-O) = 1.659(2) {angstrom} in P4{sub 2}/n and is identical to the (T2-O) = 1.659(1) {angstrom} in I4/m. The (M-O) [7] = 2.754(1) {angstrom} (M site is coordinated to seven framework O atoms) and M-A = 2.914(1) {angstrom}; these distances are identical in both space groups. The Me{sub 93} sample has a formula of Na{sub 0.29}Ca{sub 3.76}[Al{sub 5.54}Si{sub 6.46}O{sub 24}]Cl{sub 0.05}(SO{sub 4}){sub 0.02}(CO{sub 3}){sub 0.93}, and its unit-cell parameters are a = 12.19882(1), c = 7.576954(8) {angstrom}, and V = 1127.535(2) {angstrom}{sup 3}. A similar examination of the Me{sub 93} sample also shows that both space groups give similar results; however, the C-O distance is more reasonable in P4{sub 2}/n than in I4/m. Refining the scapolite structure near Me{sub 0} or Me{sub 100} in I4/m forces the T2 and T3 sites (both with multiplicity 8 in P4{sub 2}/n) to be equivalent and form the T2' site (with multiplicity 16 in I4/m), but (T2-O) is not equal to (T3-O) in P4{sub 2}/n. Using different space groups for different regions across the series implies phase transitions, which do not occur in the scapolite series.

  11. Mobile Robot Obstacle Avoidance Via Depth From Focus

    E-Print Network [OSTI]

    Tomasi, Carlo

    Abstract A critical challenge in the creation of autonomous mobile robots is the reliable detection radiation such as direct sunlight. In contrast, vision systems are passive and can provide lateral and depth market. However, our particular embodiment of this concept is remarkable because our focus-based system

  12. WaveCurrent Interactions in Finite Depth JEROME A. SMITH

    E-Print Network [OSTI]

    Smith, Jerome A.

    Wave­Current Interactions in Finite Depth JEROME A. SMITH Scripps Institution of Oceanography, La (Longuet-Higgins 1969; Hasselmann 1971; Garrett and Smith 1976; and many others). In particular, Hassel) changes in wave momentum that absorb some of the radiation stress gradients. Garrett and Smith (1976

  13. Continuous Snow Depth, Intensive Site 1, Barrow, Alaska

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Cable, William; Romanovsky, Vladimir; Hinzman, Larry; Busey, Bob

    Continuous Snow depth data are being collected at several points within four intensive study areas in Barrow, Alaska. These data are being collected to better understand the energy dynamics above the active layer and permafrost. They complement in-situ snow and soil measurements at this location. The data could also be used as supporting measurements for other research and modeling activities.

  14. Correction to “Hyperspectral Aerosol Optical Depths from TCAP Flights”

    SciTech Connect (OSTI)

    Shinozuka, Yohei; Johnson, Roy R.; Flynn, Connor J.; Russell, P. B.; Schmid, Beat; Redemann, Jens; Dunagan, Stephen; Kluzek, Celine D.; Hubbe, John M.; Segal-Rosenheimer, Michal; Livingston, J. M.; Eck, T.; Wagener, Richard; Gregory, L.; Chand, Duli; Berg, Larry K.; Rogers, Ray; Ferrare, R. A.; Hair, John; Hostetler, Chris A.; Burton, S. P.

    2014-02-16T23:59:59.000Z

    In the paper “Hyperspectral aerosol optical depths from TCAP flights” by Y. Shinozuka et al. (Journal of Geophysical Research: Atmospheres, 118, doi:10.1002/2013JD020596, 2013), Tables 1 and 2 were published with the column heads out of order. Tables 1 and 2 are published correctly here. The publisher regrets the error.

  15. Wave-current interaction in water of finite depth

    E-Print Network [OSTI]

    Huang, Zhenhua, 1967-

    2004-01-01T23:59:59.000Z

    In this thesis, the nonlinear interaction of waves and current in water of finite depth is studied. Wind is not included. In the first part, a 2D theory for the wave effect on a turbulent current over rough or smooth bottom ...

  16. 7 Predictive Risk Mapping of Water Table Depths in

    E-Print Network [OSTI]

    Camara, Gilberto

    , and so risks of water shortage appear. The preservation of these resources is important because73 7 Predictive Risk Mapping of Water Table Depths in a Brazilian Cerrado Area R. L. Manzione, M metabolize throughout the year, drawing on soil water reserves, and can withstand short-lived fires. contents

  17. In-Depth Temperature Profiles in Pyrolyzing Wood 

    E-Print Network [OSTI]

    Reszka, Pedro

    of experimental in-depth temperature measurements were done in wood samples exposed to various intensities of radiant heat fluxes, with clearly defined boundary conditions that allow a proper input for pyrolysis models. The imposed heat fluxes range from 10 k...

  18. PROOF COMPLEXITY IN ALGEBRAIC SYSTEMS AND BOUNDED DEPTH FREGE

    E-Print Network [OSTI]

    Sgall, Jiri

    PROOF COMPLEXITY IN ALGEBRAIC SYSTEMS AND BOUNDED DEPTH FREGE SYSTEMS WITH MODULAR COUNTING S. Buss (ø) := minfjßj : f(ß) = øg; #12; 2 S. Buss et al. where jßj is the length of the string ß to showing that NP 6= coNP . Despite extensive research (see the expository articles Buss (1995b) , Kraj

  19. accurate hydrogen depth: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    accurate hydrogen depth First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Accurate reconstruction of the...

  20. Ab initio theory of phase transitions and thermoelasticity of minerals

    E-Print Network [OSTI]

    Oganov, Artem R.

    Ab initio theory of phase transitions and thermoelasticity of minerals ARTEM R. OGANOV* , JOHN P transitions, equations of state, elasticity and thermoelastic properties of the Earth-forming minerals minerals at the extreme conditions of the Earth's interior. One can accurately predict the structures

  1. Buckling transition in long ?-helices

    SciTech Connect (OSTI)

    Palen?ár, Peter; Bleha, Tomáš, E-mail: bleha@savba.sk [Polymer Institute, Slovak Academy of Sciences, 845 41 Bratislava (Slovakia)

    2014-11-07T23:59:59.000Z

    The treatment of bending and buckling of stiff biopolymer filaments by the popular worm-like chain model does not provide adequate understanding of these processes at the microscopic level. Thus, we have used the atomistic molecular-dynamic simulations and the Amber03 force field to examine the compression buckling of ?-helix (AH) filaments at room temperature. It was found that the buckling instability occurs in AHs at the critical force f{sub c} in the range of tens of pN depending on the AH length. The decrease of the force f{sub c} with the contour length follows the prediction of the classic thin rod theory. At the force f{sub c} the helical filament undergoes the swift and irreversible transition from the smoothly bent structure to the buckled one. A sharp kink in the AH contour arises at the transition, accompanied by the disruption of the hydrogen bonds in its vicinity. The kink defect brings in an effective softening of the AH molecule at buckling. Nonbonded interactions between helical branches drive the rearrangement of a kinked AH into the ultimate buckled structure of a compact helical hairpin described earlier in the literature.

  2. Accessibility-based transit planning

    E-Print Network [OSTI]

    Busby, Jeffrey R

    2004-01-01T23:59:59.000Z

    A method for evaluating transit planning proposals using accessibility metrics is advanced in this research. A transit-accessibility model is developed intended for use by in-house transit agency planning staff as a ...

  3. Holographic Magnetic Phase Transition

    E-Print Network [OSTI]

    Gilad Lifschytz; Matthew Lippert

    2009-06-21T23:59:59.000Z

    We study four-dimensional interacting fermions in a strong magnetic field, using the holographic Sakai-Sugimoto model of intersecting D4 and D8 branes in the deconfined, chiral-symmetric parallel phase. We find that as the magnetic field is varied, while staying in the parallel phase, the fermions exhibit a first-order phase transition in which their magnetization jumps discontinuously. Properties of this transition are consistent with a picture in which some of the fermions jump to the lowest Landau level. Similarities to known magnetic phase transitions are discussed.

  4. On vosperian and superconnected vertex-transitive digraphs

    E-Print Network [OSTI]

    Hamidoune, Y O; López, S C

    2010-01-01T23:59:59.000Z

    We investigate the structure of a digraph having a transitive automorphism group where every cutset of minimal cardinality consists of all successors or all predecessors of some vertex. We improve most of the existing results in this area.

  5. Thermodynamic and morphological transitions in crystalline and soft material interfaces

    E-Print Network [OSTI]

    Tang, Ming, Ph. D. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    Interfaces are defects present in all materials. Interface transitions are characterized by abrupt changes in interface structure, chemistry and/or morphology under suitable conditions. They exist in many material systems ...

  6. Transition from Irradiation-Induced Amorphization to Crystallization...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    nanocrystalline SiC on nuclear fuel cladding and structural components of next-generation nuclear energy systems. Citation: Jiang W, L Jiao, and H Wang.2011."Transition from...

  7. Charge, orbital and magnetic ordering in transition metal oxides 

    E-Print Network [OSTI]

    Senn, Mark Stephen

    2013-06-29T23:59:59.000Z

    Neutron and x-ray diffraction has been used to study charge, orbital and magnetic ordering in some transition metal oxides. The long standing controversy regarding the nature of the ground state (Verwey structure) of the ...

  8. Wildfire Policy in Transition Yellowstone

    E-Print Network [OSTI]

    Wildfire Policy in Transition 1910 #12;Yellowstone 1988 #12;Colorado South Canyon Fire 1994 #12;#12;Wildfire Policy in Transition 1910 #12;

  9. A NEW MULTIDIRECTIONAL EXTRAPOLATION HOLE-FILLING METHOD FOR DEPTH-IMAGE-BASED RENDERING

    E-Print Network [OSTI]

    Po, Lai-Man

    A NEW MULTIDIRECTIONAL EXTRAPOLATION HOLE-FILLING METHOD FOR DEPTH-IMAGE-BASED RENDERING Lai-Man Po School of Peking University, Shenzhen, China ABSTRACT Depth-Image-Based Rendering (DIBR) is widely used synthesis with high-quality depth map. Index Terms - Depth-Image-Based-Rendering, DIBR, Hole

  10. RFID tag modification for full depth backscatter modulation

    DOE Patents [OSTI]

    Scott, Jeffrey Wayne [Pasco, WA; Pratt, Richard M [Richland, WA

    2010-07-20T23:59:59.000Z

    A modulated backscatter radio frequency identification device includes a diode detector configured to selectively modulate a reply signal onto an incoming continuous wave; communications circuitry configured to provide a modulation control signal to the diode detector, the diode detector being configured to modulate the reply signal in response to be modulation control signal; and circuitry configured to increase impedance change at the diode detector which would otherwise not occur because the diode detector rectifies the incoming continuous wave while modulating the reply signal, whereby reducing the rectified signal increases modulation depth by removing the reverse bias effects on impedance changes. Methods of improving depth of modulation in a modulated backscatter radio frequency identification device are also provided.

  11. Using the Multi-Depth Deflectometer to study pavement response

    E-Print Network [OSTI]

    Yazdani, Jamshed Iqbal

    1989-01-01T23:59:59.000Z

    - Section 11 (Load: 8500 lbs. ) Variation of layer moduli backcalculated from depth deflections - Section 11 (Load: 16000 lbs. ) Measured deflections - Section 12 Moduli values backcalculated from BISAR - Section 12, Infinite subgrade . Moduli values... . Typical N? versus bulk stress (8) relationship for granular materials . MDD deflection basin measured under FWD load- 8500 lb. load level 143 144 145 146 148 149 67 68 NDD deflection basin predicted from BISAR Measured versus predicted...

  12. Depth Profile Analysis of New Materials in Hollow Cathode Discharge

    SciTech Connect (OSTI)

    Djulgerova, R.; Mihailov, V.; Gencheva, V.; Popova, L.; Panchev, B. [Institute of Solid State Physics - Bulgarian Academy of Sciences, 1784 Sofia (Bulgaria); Michaylova, V. [Technical University of Sofia, 1797 Sofia (Bulgaria); Szytula, A.; Gondek, L.; Dohnalik, T.M. [Smoluchowski Institute of Physics - Jagellonian University, 30-059 Cracow (Poland); Petrovic, Z.Lj. [Institute of Physics, 11080 Zemun, Belgrade (Serbia and Montenegro)

    2004-12-01T23:59:59.000Z

    In this review the possibility of hollow cathode discharge for depth profile analysis is demonstrated for several new materials: planar optical waveguides fabricated by Ag+-Na+ ion exchange process in glasses, SnO2 thin films for gas sensors modified by hexamethildisilazane after rapid thermal annealing, W- and WC- CVD layers deposited on Co-metalloceramics and WO3- CVD thin films deposited on glass. The results are compared with different standard techniques.

  13. Obtaining anisotropic velocity data for proper depth seismic imaging

    SciTech Connect (OSTI)

    Egerev, Sergey; Yushin, Victor; Ovchinnikov, Oleg; Dubinsky, Vladimir; Patterson, Doug [Andreyev Acoustics Institute, Moscow, 117036 (Russian Federation); Baker Hughes, Inc, 2001 Rankin Road, Houston, TX, 77073 (United States)

    2012-05-24T23:59:59.000Z

    The paper deals with the problem of obtaining anisotropic velocity data due to continuous acoustic impedance-based measurements while scanning in the axial direction along the walls of the borehole. Diagrams of full conductivity of the piezoceramic transducer were used to derive anisotropy parameters of the rock sample. The measurements are aimed to support accurate depth imaging of seismic data. Understanding these common anisotropy effects is important when interpreting data where it is present.

  14. Bus Centric Rapid Transit

    E-Print Network [OSTI]

    Banasiak, J.

    2011-01-01T23:59:59.000Z

    Transfer Center TOD ? SmartCode/CNU Goals ? Public/private development partnership ? Emphasis on the pedestrian ? Bicycle and transit oriented development ? Dover Kohl TOD report, Dec. 2010 ? WTC will be anchor and terminus for BRT 11 18 Westside... Transfer Center 18 18 Five Points TOD #2 15 Five Points TOD 16 ? SmartCode/CNU Goals ? Public/private development partnership ? Emphasis on the pedestrian ? Bicycle and transit oriented development ? Dover Kohl TOD report, Dec. 2010 ? Five...

  15. High-Resolution Microtubule Structures Reveal the Structural Transitions

    E-Print Network [OSTI]

    Baker, David

    Baker,3 and Eva Nogales2,4,* 1Biophysics Graduate Program, University of California, Berkeley, BerkeleyHoward Hughes Medical Institute, Department of Biochemistry, University of Washington, Seattle, WA 98105, USA 4Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University

  16. Pressure induced phase transitions in ceramic compounds containing tetragonal zirconia

    SciTech Connect (OSTI)

    Sparks, R.G.; Pfeiffer, G.; Paesler, M.A.

    1988-12-01T23:59:59.000Z

    Stabilized tetragonal zirconia compounds exhibit a transformation toughening process in which stress applied to the material induces a crystallographic phase transition. The phase transition is accompanied by a volume expansion in the stressed region thereby dissipating stress and increasing the fracture strength of the material. The hydrostatic component of the stress required to induce the phase transition can be investigated by the use of a high pressure technique in combination with Micro-Raman spectroscopy. The intensity of Raman lines characteristic for the crystallographic phases can be used to calculate the amount of material that has undergone the transition as a function of pressure. It was found that pressures on the order of 2-5 kBar were sufficient to produce an almost complete transition from the original tetragonal to the less dense monoclinic phase; while a further increase in pressure caused a gradual reversal of the transition back to the original tetragonal structure.

  17. Report on the Depth Requirements for a Massive Detector at Homestake

    SciTech Connect (OSTI)

    Kadel, Richard W.; Bernstein, Adam; Blucher, Edward; Cline, David B.; Diwan, Milind V.; Fleming, Bonnie; Kearns, Edward; Klein, Joshua; Lande, Kenneth; Lanni, Francesco; Lissauer, David; McKeown, Robert; Morse, William; Rameika, Regina; Scholberg, Kate; Smy, Michael; Sobel, Henry; Sullivan, Gregory; Svoboda, Robert; Vagins, Mark; Walter, Christopher; Zwaska, Robert

    2008-12-23T23:59:59.000Z

    This report provides the technical justification for locating a large detector underground in a US based Deep Underground Science and Engineering Laboratory. A large detector with a fiducial mass greater than 100 kTon will most likely be a multipurpose facility. The main physics justification for such a device is detection of accelerator generated neutrinos, nucleon decay, and natural sources of neutrinos such as solar, atmospheric and supernova neutrinos. The requirement on the depth of this detector will be guided by the rate of signals from these sources and the rate of backgrounds from cosmic rays over a very wide range of energies (from solar neutrino energies of 5 MeV to high energies in the range of hundreds of GeV). For the present report, we have examined the depth requirement for a large water Cherenkov detector and a liquid argon time projection chamber. There has been extensive previous experience with underground water Cherenkov detectors such as IMB, Kamioka, and most recently, Super-Kamiokande which has a fiducial mass of 22 kTon and a total mass of 50 kTon at a depth of 2700 meters-water-equivalent in a mountain. Projections for signal and background capability for a larger and deeper(or shallower) detectors of this type can be scaled from these previous detectors. The liquid argon time projection chamber has the advantage of being a very fine-grained tracking detector, which should provide enhanced capability for background rejection. We have based background rejection on reasonable estimates of track and energy resolution, and in some cases scaled background rates from measurements in water. In the current work we have taken the approach that the depth should be sufficient to suppress the cosmogenic background below predicted signal rates for either of the above two technologies. Nevertheless, it is also clear that the underground facility that we are examining must have a long life and will most likely be used either for future novel uses of the currently planned detectors or new technologies. Therefore the depth requirement also needs to be made on the basis of sound judgment regarding possible future use. In particular, the depth should be sufficient for any possible future use of these cavities or the level which will be developed for these large structures.Along with these physics justifications there are practical issues regarding the existing infrastructure at Homestake and also the stress characteristics of the Homestake rock formations. In this report we will examine the various depth choices at Homestake from the point of view of the particle and nuclear physics signatures of interest. We also have sufficient information about the existing infrastructure and the rock characteristics to narrow the choice of levels for the development of large cavities with long lifetimes. We make general remarks on desirable ground conditions for such large cavities and then make recommendations on how to start examining these levels to make a final choice. In the appendix we have outlined the initial requirements for the detectors. These requirements will undergo refinement during the course of the design. Finally, we strongly recommend that the geotechnical studies be commenced at the 4850 ft level, which we find to be the most suitable, in a timely manner.

  18. Report on the Depth Requirements for a Massive Detector at Homestake

    SciTech Connect (OSTI)

    Bernstein,A.; Blucher, E.; Cline, D. B.; Diwan, M. V.; Fleming, b.; Kadel, R.; Kearns, E.; Klein, J.; Lande, K.; Lanni, F.; Lissauer, D.; McKeown, R.; Morse, W.; Radeika, R.; Scholberg, K.; Smy, M.; Sobel, H.; Sullivan, G.; Svoboda, R.; Vagins, M.; Walter, C.; Zwaska, R.

    2008-12-22T23:59:59.000Z

    This report provides the technical justification for locating a large detector underground in a US based Deep Underground Science and Engineering Laboratory. A large detector with a fiducial mass greater than 100 kTon will most likely be a multipurpose facility. The main physics justification for such a device is detection of accelerator generated neutrinos, nucleon decay, and natural sources of neutrinos such as solar, atmospheric and supernova neutrinos. The requirement on the depth of this detector will be guided by the rate of signals from these sources and the rate of backgrounds from cosmic rays over a very wide range of energies (from solar neutrino energies of 5 MeV to high energies in the range of tens of GeV). For the present report, we have examined the depth requirement for a large water Cherenkov detector and a liquid argon time projection chamber. There has been extensive previous experience with underground water Cherenkov detectors such as IMB, Kamioka, and most recently, Super-Kamiokande which has a fiducial mass of 22 kTon and a total mass of 50 kTon at a depth of 2700 meters-water-equivalent. Projections for signal and background capability for a larger and deeper (or shallower) detectors of this type can be scaled from these previous detectors. The liquid argon time projection chamber has the advantage of being a very fine-grained tracking detector, which provides enhanced capability for background rejection. In the current work we have taken the approach that the depth should be sufficient to suppress the cosmogenic background below predicted signal rates for either of the above two technologies. Nevertheless, it is also clear that the underground facility that we are examining must have a long life and will most likely be used either for future novel uses of the currently planned detectors or new technologies. Therefore the depth requirement also needs to be made on the basis of sound judgment regarding possible future use. In particular, the depth should be sufficient for any possible future use of these cavities or the level which will be developed for these large structures. Along with these physics justifications there are practical issues regarding the existing infrastructure at Homestake and also the stress characteristics of the Homestake rock formations. In this report we will examine the various depth choices at Homestake from the point of view of the particle and nuclear physics signatures of interest. We also have sufficient information about the existing infrastructure and the rock characteristics to narrow the choice of levels for the development of large cavities with long lifetimes. We make general remarks on desirable ground conditions for such large cavities and then make recommendations on how to start examining these levels to make a final choice. In the appendix we have outlined the initial requirements for the detectors. These requirements will undergo refinement during the course of the design. Finally, we strongly recommend that the geotechnical studies be commenced at the 4850 ft level, which we find to be the most suitable, in a timely manner.

  19. Using color photometry to separate transiting exoplanets from false positives

    E-Print Network [OSTI]

    B. Tingley

    2004-07-14T23:59:59.000Z

    The radial velocity technique is currently used to classify transiting objects. While capable of identifying grazing binary eclipses, this technique cannot reliably identify blends, a chance overlap of a faint background eclipsing binary with an ordinary foreground star. Blends generally have no observable radial velocity shifts, as the foreground star is brighter by several magnitudes and therefore dominates the spectrum, but their combined light can produce events that closely resemble those produced by transiting exoplanets. The radial velocity technique takes advantage of the mass difference between planets and stars to classify exoplanet candidates. However, the existence of blends renders this difference an unreliable discriminator. Another difference must therefore be utilized for this classification -- the physical size of the transiting body. Due to the dependence of limb darkening on color, planets and stars produce subtly different transit shapes. These differences can be relatively weak, little more than 1/10th the transit depth. However, the presence of even small color differences between the individual components of the blend increases this difference. This paper will show that this color difference is capable of discriminating between exoplanets and blends reliably, theoretically capable of classifying even terrestrial-class transits, unlike the radial velocity technique.

  20. Semi-empirical model for depth dose distributions of megavoltage x-ray beams

    SciTech Connect (OSTI)

    Ahuja, S.D.; Stroup, S.L.; Bolin, M.G.

    1980-09-01T23:59:59.000Z

    The dose distribution due to absorption of photon energy fluence in a homogeneous water phantom irradiated by megavoltage x-ray beams has been analyzed with a semiempirical model. The method generalizes an analytical formalism for the scattering component of dose within a water phantom which was developed recently for monoenergetic photon beams. Contributions to dose via Compton interaction and pair creation form the essential structure of the secondary component formula. Both the central-axis percent depth dose and off-central-axis ratios can be determined for beams of different sizes, used at any value of source to surface distance. The input data include the values of linear attenuation and energy-absorption coefficients in water at energies between 10 keV and the equivalent energy of the beam. Predicted values of the central-axis percent depth dose and the off-central-axis ratios are compared with the measured data for 2, 4, 6, 8, 10, 14, 20, 35, 45, and 70 MVp x-ray beams. For the central-axis percent depth dose, agreement is within 3% for fields of sizes between 5 x 5 and 20 x 20 cm/sup 2/, and 5% for larger fields, for beams of MVp up to 20. For higher energy beams, comparison was made only for the 10 x 10 cm/sup 2/ fields and the discrepancies were within 3%. For the off-central-axis ratios, agreement between the predicted and measured values is within 5% over the umbra region but worsens in the penumbra region and geometrical shadow. This formalism requires large computer storage for generating data for all realistic beams irradiating normal-size phantoms.

  1. Nuclear Physics A 635 (1998) 4701483 Boson forbidden low-energy E1-transitions

    E-Print Network [OSTI]

    Ponomarev, Vladimir

    1998-01-01T23:59:59.000Z

    Nuclear Physics A 635 (1998) 4701483 Boson forbidden low-energy E1-transitions in spherical nuclei; accepted 23 March 1998 Abstract Low-energy E1-transitions in spherical nuclei forbidden in the ideal boson.V. PACS: 21.60.-n; 21.60.Jz; 23.20.-g Keywords: Low-energy E1-transitions; Fermion structure of phonons

  2. Functionalized Silicone Nanospheres: Synthesis, Transition Metal...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Functionalized Silicone Nanospheres: Synthesis, Transition Metal Immobilization, and Catalytic Applications. Functionalized Silicone Nanospheres: Synthesis, Transition Metal...

  3. Examining hydrogen transitions.

    SciTech Connect (OSTI)

    Plotkin, S. E.; Energy Systems

    2007-03-01T23:59:59.000Z

    This report describes the results of an effort to identify key analytic issues associated with modeling a transition to hydrogen as a fuel for light duty vehicles, and using insights gained from this effort to suggest ways to improve ongoing modeling efforts. The study reported on here examined multiple hydrogen scenarios reported in the literature, identified modeling issues associated with those scenario analyses, and examined three DOE-sponsored hydrogen transition models in the context of those modeling issues. The three hydrogen transition models are HyTrans (contractor: Oak Ridge National Laboratory), MARKAL/DOE* (Brookhaven National Laboratory), and NEMS-H2 (OnLocation, Inc). The goals of these models are (1) to help DOE improve its R&D effort by identifying key technology and other roadblocks to a transition and testing its technical program goals to determine whether they are likely to lead to the market success of hydrogen technologies, (2) to evaluate alternative policies to promote a transition, and (3) to estimate the costs and benefits of alternative pathways to hydrogen development.

  4. Halite depositional facies in a solar salt pond: A key to interpreting physical energy and water depth in ancient deposits

    SciTech Connect (OSTI)

    Handford, C.R. (ARCO Oil and Gas Co., Plano, TX (USA))

    1990-08-01T23:59:59.000Z

    Subaqueous deposits of aragonite, gypsum, and halite are accumulating in shallow solar salt ponds constructed in the Pekelmeer, a sea-level salina on Bonaire, Netherlands Antilles. Several halite facies are deposited in the crystallizer ponds in response to difference in water depth and wave energy. Cumulate halite, which originates as floating rafts, is present only along the protected, upwind margins of ponds where low-energy conditions foster their formation and preservation. Cornet crystals with peculiar mushroom- and mortarboard-shaped caps precipitate in centimetre-deep brine sheets within a couple of metres of the upwind or low-energy margins. Downwind from these margins, cornet and chevron halite precipitate on the pond floors in water depths ranging from a few centimetres to {approximately} 60 cm. Halite pisoids with radial-concentric structure are precipitated in the swash zone along downwind high-energy shorelines where they form pebbly beaches. This study suggests that primary halite facies are energy and/or depth dependent and that some primary features, if preserved in ancient halite deposits, can be used to infer physical energy conditions, subenvironments such as low- to high-energy shorelines, and extremely shallow water depths in ancient evaporite basins.

  5. The Effects of Geometry on the Corona-to-Streamer Discharge Transition

    E-Print Network [OSTI]

    Humbird, Kelli D

    2013-01-31T23:59:59.000Z

    The electric spark discharge has been studied for hundreds of years, yet many details of the phenomenon remain elusive. One particular area in the field of spark discharges that has yet to be explored in depth is the transition region between...

  6. Average Depth of Crude Oil and Natural Gas Wells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProductsAlternativeOperationalAugust AugustInstruments on the Site MapDepth of

  7. Property:AvgReservoirDepth | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,Pillar Group BV Jump to:Information PromotingApplicantAvgReservoirDepth Jump

  8. Property:AvgWellDepth | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,Pillar Group BV Jump to:Information PromotingApplicantAvgReservoirDepth

  9. Property:FirstWellDepth | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag Jump to: navigation, search Property NameFirstWellDepth Jump to: navigation, search

  10. Heat Flow At Standard Depth | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetec AG|Information OpenEIHas BeenLegalHeard County,Grain FuelsDepth Jump

  11. Average Depth of Crude Oil and Natural Gas Wells

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Year-0 Year-1 Year-21960-2012Mission: Focus onDepth of Crude Oil and

  12. Sudden gravitational transition

    SciTech Connect (OSTI)

    Caldwell, Robert R. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, New Hampshire 03755 (United States); Komp, William [Physics Department, University of Louisville, 102 Natural Sciences, Louisville, Kentucky 40292 (United States); Parker, Leonard [Physics Department, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States); Vanzella, Daniel A. T. [Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo (IFSC-USP), Av. Trabalhador Sao-carlense, 400 Cx. Postal 369 - CEP 13560-970, Sao Carlos, Sao Paulo (Brazil)

    2006-01-15T23:59:59.000Z

    We investigate the properties of a cosmological scenario which undergoes a gravitational phase transition at late times. In this scenario, the Universe evolves according to general relativity in the standard, hot big bang picture until a redshift z < or approx. 1. Nonperturbative phenomena associated with a minimally-coupled scalar field catalyzes a transition, whereby an order parameter consisting of curvature quantities such as R{sup 2}, R{sub ab}R{sup ab}, R{sub abcd}R{sup abcd} acquires a constant expectation value. The ensuing cosmic acceleration appears driven by a dark-energy component with an equation-of-state w<-1. We evaluate the constraints from type 1a supernovae, the cosmic microwave background, and other cosmological observations. We find that a range of models making a sharp transition to cosmic acceleration are consistent with observations.

  13. Electroweak phase transitions

    SciTech Connect (OSTI)

    Anderson, G.W.

    1991-09-16T23:59:59.000Z

    An analytic treatment of the one Higgs doublet, electroweak phase transition is given. The phase transition is first order, occurs by the nucleation of thin walled bubbles and completes at a temperature where the order parameter, {l_angle}{phi}{r_angle}{sub T} is significantly smaller than it is when the origin becomes absolutely unstable. The rate of anomalous baryon number violation is an exponentially function of {l_angle}{phi}{r_angle}{sub T}. In very minimal extensions of the standard model it is quite easy to increase {l_angle}{phi}{r_angle}{sub T} so that anomalous baryon number violation is suppressed after completion of the phase transition. Hence baryogenesis at the electroweak phase transition is tenable in minimal of the standard model. In some cases additional phase transitions are possible. For a light Higgs boson, when the top quark mass is sufficiently large, the state where the Higgs field has a vacuum expectation value {l_angle}{phi}{r_angle} = 246 GeV is not the true minimum of the Higgs potential. When this is the case, and when the top quark mass exceeds some critical value, thermal fluctuations in the early universe would have rendered the state {l_angle}{phi}{r_angle} = 246 GeV unstable. The requirement that the state {l_angle}{phi}{r_angle} = 246 GeV is sufficiently long lived constrains the masses of the Higgs boson and the top quark. Finally, we consider whether local phase transitions can be induced by heavy particles which act as seeds for deformations in the scalar field.

  14. Electroweak phase transitions

    SciTech Connect (OSTI)

    Anderson, G.W.

    1991-09-16T23:59:59.000Z

    An analytic treatment of the one Higgs doublet, electroweak phase transition is given. The phase transition is first order, occurs by the nucleation of thin walled bubbles and completes at a temperature where the order parameter, {l angle}{phi}{r angle}{sub T} is significantly smaller than it is when the origin becomes absolutely unstable. The rate of anomalous baryon number violation is an exponentially function of {l angle}{phi}{r angle}{sub T}. In very minimal extensions of the standard model it is quite easy to increase {l angle}{phi}{r angle}{sub T} so that anomalous baryon number violation is suppressed after completion of the phase transition. Hence baryogenesis at the electroweak phase transition is tenable in minimal of the standard model. In some cases additional phase transitions are possible. For a light Higgs boson, when the top quark mass is sufficiently large, the state where the Higgs field has a vacuum expectation value {l angle}{phi}{r angle} = 246 GeV is not the true minimum of the Higgs potential. When this is the case, and when the top quark mass exceeds some critical value, thermal fluctuations in the early universe would have rendered the state {l angle}{phi}{r angle} = 246 GeV unstable. The requirement that the state {l angle}{phi}{r angle} = 246 GeV is sufficiently long lived constrains the masses of the Higgs boson and the top quark. Finally, we consider whether local phase transitions can be induced by heavy particles which act as seeds for deformations in the scalar field.

  15. Synthesis of transition metal carbonitrides

    DOE Patents [OSTI]

    Munir, Zuhair A. R. (Davis, CA); Eslamloo-Grami, Maryam (Davis, CA)

    1994-01-01T23:59:59.000Z

    Transition metal carbonitrides (in particular, titanium carbonitride, TiC.sub.0.5 N.sub.0.5) are synthesized by a self-propagating reaction between the metal (e.g., titanium) and carbon in a nitrogen atmosphere. Complete conversion to the carbonitride phase is achieved with the addition of TiN as diluent and with a nitrogen pressure .gtoreq.0.6 MPa. Thermodynamic phase-stability calculations and experimental characterizations of quenched samples provided revealed that the mechanism of formation of the carbonitride is a two-step process. The first step involves the formation of the nonstoichiometric carbide, TiC.sub.0.5, and is followed by the formation of the product by the incorporation of nitrogen in the defect-structure carbide.

  16. An in-depth longitudinal analysis of mixing patterns in a small scientific collaboration network

    SciTech Connect (OSTI)

    Rodriguez, Marko A [Los Alamos National Laboratory; Pepe, Alberto [UCLA

    2009-01-01T23:59:59.000Z

    Many investigations of scientific collaboration are based on large-scale statistical analyses of networks constructed from bibliographic repositories. These investigations often rely on a wealth of bibliographic data, but very little or no other information about the individuals in the network, and thus, fail to illustate the broader social and academic landscape in which collaboration takes place. In this article, we perform an in-depth longitudinal analysis of a small-scale network of scientific collaboration (N = 291) constructed from the bibliographic record of a research center involved in the development and application of sensor network technologies. We perform a preliminary analysis of selected structural properties of the network, computing its range, configuration and topology. We then support our preliminary statistical analysis with an in-depth temporal investigation of the assortativity mixing of these node characteristics: academic department, affiliation, position, and country of origin of the individuals in the network. Our qualitative analysis of mixing patterns offers clues as to the nature of the scientific community being modeled in relation to its organizational, disciplinary, institutional, and international arrangements of collaboration.

  17. The Physics of the Colloidal Glass Transition

    E-Print Network [OSTI]

    Gary L. Hunter; Eric R. Weeks

    2011-12-20T23:59:59.000Z

    As one increases the concentration of a colloidal suspension, the system exhibits a dramatic increase in viscosity. Structurally, the system resembles a liquid, yet motions within the suspension are slow enough that it can be considered essentially frozen. This kinetic arrest is the colloidal glass transition. For several decades, colloids have served as a valuable model system for understanding the glass transition in molecular systems. The spatial and temporal scales involved allow these systems to be studied by a wide variety of experimental techniques. The focus of this review is the current state of understanding of the colloidal glass transition. A brief introduction is given to important experimental techniques used to study the glass transition in colloids. We describe features of colloidal systems near and in glassy states, including tremendous increases in viscosity and relaxation times, dynamical heterogeneity, and ageing, among others. We also compare and contrast the glass transition in colloids to that in molecular liquids. Other glassy systems are briefly discussed, as well as recently developed synthesis techniques that will keep these systems rich with interesting physics for years to come.

  18. Viscosity near phase transitions

    E-Print Network [OSTI]

    Antonio Dobado; Felipe J. Llanes-Estrada; Juan M. Torres-Rincon

    2010-09-30T23:59:59.000Z

    Probably the most enticing observation in theoretical physics during the last decade was the discovery of the great amount of consequences obtained from the AdS/CFT conjecture put forward by Maldacena. In this work we review how this correspondence can be used to address hydrodynamic properties such as the viscosity of some strongly interacting systems. We also employ the Boltzmann equation for those systems closer to low-energy QCD, and argue that this kind of transport coefficients can be related to phase transitions, in particular the QGP/hadronic phase transition studied in heavy ion collisions.

  19. Low temperature London penetration depth and superfluid density in Fe-based superconductors

    SciTech Connect (OSTI)

    Kim, Hyunsoo [Ames Laboratory] [Ames Laboratory

    2013-05-15T23:59:59.000Z

    The superconducting gap symmetry of the Fe-based superconductors was studied by measurements and analysis of London penetration depth and super uid density. Tunnel diode resonator technique for these measurements was implemented in a dilution refrigerator allowing for the temperatures down to 50 mK. For the analysis of the super uid density, we used both experimental studies of Al-coated samples and original thermodynamic approach based on Rutgers relation. In three systems studied, we found that the superconducting gap at the optimal doping is best described in multi-gap full gap scenario. By performing experiments on samples with arti#12;cially introduced disorder with heavy ion irradiation, we show that evolution of the superconducting transition temperature and of the super uid density are consistent with full-gap sign changing s#6; superconducting state. The superconducting gap develops strong modulation both in the under-doped and the over-doped regimes. In the terminal hole-doped KFe{sub 2}As{sub 2}, both temperature dependence of the super uid density and its evolution with increase of the scattering rate are consistent with symmetry imposed vertical line nodes in the superconducting gap. By comparative studies of hole-doped (Ba,K)Fe{sub 2}As{sub 2} and electron-doped Ca10-3-8, we show that the superconducting gap modulation in the under-doped regime is intrinsic and is not induced by the coexisting static magnetic order.

  20. Transition temperature in QCD

    SciTech Connect (OSTI)

    Cheng, M.; Christ, N. H.; Mawhinney, R. D. [Physics Department, Columbia University, New York, New York 10027 (United States); Datta, S.; Jung, C.; Schmidt, C.; Umeda, T. [Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States); Heide, J. van der; Kaczmarek, O.; Laermann, E.; Miao, C. [Fakultaet fuer Physik, Universitaet Bielefeld, D-33615 Bielefeld (Germany); Karsch, F. [Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States); Fakultaet fuer Physik, Universitaet Bielefeld, D-33615 Bielefeld (Germany); Petreczky, P. [Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States); RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973 (United States); Petrov, K. [Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen (Denmark)

    2006-09-01T23:59:59.000Z

    We present a detailed calculation of the transition temperature in QCD with two light and one heavier (strange) quark mass on lattices with temporal extent N{sub {tau}}=4 and 6. Calculations with improved staggered fermions have been performed for various light to strange quark mass ratios in the range, 0.05{<=}m-circumflex{sub l}/m-circumflex{sub s}{<=}0.5, and with a strange quark mass fixed close to its physical value. From a combined extrapolation to the chiral (m-circumflex{sub l}{yields}0) and continuum (aT{identical_to}1/N{sub {tau}}{yields}0) limits we find for the transition temperature at the physical point T{sub c}r{sub 0}=0.457(7) where the scale is set by the Sommer-scale parameter r{sub 0} defined as the distance in the static quark potential at which the slope takes on the value (dV{sub qq}(r)/dr){sub r=r{sub 0}}=1.65/r{sub 0}{sup 2}. Using the currently best known value for r{sub 0} this translates to a transition temperature T{sub c}=192(7)(4) MeV. The transition temperature in the chiral limit is about 3% smaller. We discuss current ambiguities in the determination of T{sub c} in physical units and also comment on the universal scaling behavior of thermodynamic quantities in the chiral limit.

  1. Transition Implementation Guide

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-04-24T23:59:59.000Z

    This Guide was prepared to aid in the development, planning, and implementation of requirements and activities during the transition phase at Department of Energy (DOE) facilities that have been declared or are forecast to become excess to any future mission requirements.

  2. TRANSITION STRATEGIES Sig Gronich

    E-Print Network [OSTI]

    Options. ·Natural Gas Hydrogen · Biomass Hydrogen ·Distributed Coal / IGCC Hydrogen · Compressed Gas special attention to the transition to a nascent hydrogen economy · Analyze cost goals and Liquid Storage · Electrolysis · Compressed Gas Delivery · Cold Gas Delivery and Liquid Delivery · Co

  3. Variational transition state theory

    SciTech Connect (OSTI)

    Truhlar, D.G. [Univ. of Minnesota, Minneapolis (United States)

    1993-12-01T23:59:59.000Z

    This research program involves the development of variational transition state theory (VTST) and semiclassical tunneling methods for the calculation of gas-phase reaction rates and selected applications. The applications are selected for their fundamental interest and/or their relevance to combustion.

  4. Transitions for the People: Theory and Practice of `Transition' and

    E-Print Network [OSTI]

    Watson, Andrew

    respond to the challenges, and opportunities, of Peak Oil and Climate Change?" [Transition Network 2008 change and peak-oil. There is much of interest here, for academics of sustainability transitions

  5. The Effect of Condensates on the Characterization of Transiting Planet Atmospheres with Transmission Spectroscopy

    E-Print Network [OSTI]

    Jonathan J. Fortney

    2005-09-28T23:59:59.000Z

    Through a simple physical argument we show that the slant optical depth through the atmosphere of a "hot Jupiter" planet is 35-90 times greater than the normal optical depth. This not unexpected result has direct consequences for the method of transmission spectroscopy for characterizing the atmospheres of transiting giant planets. The atmospheres of these planets likely contain minor condensates and hazes which at normal viewing geometry have negligible optical depth, but at slant viewing geometry have appreciable optical depth that can obscure absorption features of gaseous atmospheric species. We identify several possible condensates. We predict that this is a general masking mechanism for all planets, not just for HD 209458b, and will lead to weaker than expected or undetected absorption features. Constraints on an atmosphere from transmission spectroscopy are not the same as constraints on an atmosphere at normal viewing geometry.

  6. Optical and thermal depth profile reconstructions of inhomogeneous photopolymerization in dental resins using photothermal waves

    E-Print Network [OSTI]

    Mandelis, Andreas

    by a blue light-emitting diode, the x and x depth profiles were reconstructed from photothermal radiometric

  7. Control Systems Cyber Security: Defense-in-Depth Strategies

    SciTech Connect (OSTI)

    Mark Fabro

    2007-10-01T23:59:59.000Z

    Information infrastructures across many public and private domains share several common attributes regarding IT deployments and data communications. This is particularly true in the control systems domain. A majority of the systems use robust architectures to enhance business and reduce costs by increasing the integration of external, business, and control system networks. However, multi-network integration strategies often lead to vulnerabilities that greatly reduce the security of an organization, and can expose mission-critical control systems to cyber threats. This document provides guidance and direction for developing ‘defense-in-depth’ strategies for organizations that use control system networks while maintaining a multi-tier information architecture that requires: • Maintenance of various field devices, telemetry collection, and/or industrial-level process systems • Access to facilities via remote data link or modem • Public facing services for customer or corporate operations • A robust business environment that requires connections among the control system domain, the external Internet, and other peer organizations.

  8. Control Systems Cyber Security:Defense in Depth Strategies

    SciTech Connect (OSTI)

    David Kuipers; Mark Fabro

    2006-05-01T23:59:59.000Z

    Information infrastructures across many public and private domains share several common attributes regarding IT deployments and data communications. This is particularly true in the control systems domain. A majority of the systems use robust architectures to enhance business and reduce costs by increasing the integration of external, business, and control system networks. However, multi-network integration strategies often lead to vulnerabilities that greatly reduce the security of an organization, and can expose mission-critical control systems to cyber threats. This document provides guidance and direction for developing ‘defense-in-depth’ strategies for organizations that use control system networks while maintaining a multi-tier information architecture that requires: Maintenance of various field devices, telemetry collection, and/or industrial-level process systems Access to facilities via remote data link or modem Public facing services for customer or corporate operations A robust business environment that requires connections among the control system domain, the external Internet, and other peer organizations.

  9. In-depth survey report of Scoular Elevator, Salina, Kansas

    SciTech Connect (OSTI)

    Zaebst, D.D.

    1987-06-01T23:59:59.000Z

    An in/depth industrial hygiene survey of exposures to phosphine during the use of aluminum phosphide was conducted as part of a survey on exposure to grain fumigants. Area monitoring and breathing-zone sampling for phosphine were conducted during the addition of aluminum phosphide to grain during turning operations; source samples and peak personal exposures were also analyzed. Major sources of personal exposure included the escape of air from the bin headspace during filling with treated grain, filling and emptying of the phosphide pellet dispenser, and infiltration from the treated grain bin and from the pellet dispenser itself into adjacent air space. Relatively good dust control was indicated by the total dust samples collected during the survey. Measures recommended by the author are in the report.

  10. EVALUATION OF ULTRASONIC SNOW DEPTH SENSORS FOR AUTOMATED SURFACE OBSERVING SYSTEMS (ASOS)

    E-Print Network [OSTI]

    i THESIS EVALUATION OF ULTRASONIC SNOW DEPTH SENSORS FOR AUTOMATED SURFACE OBSERVING SYSTEMS (ASOS PREPARED UNDER OUR SUPERVISION BY WENDY ANN BRAZENEC ENTITLED EVALUATION OF ULTRASONIC SNOW DEPTH SENSORS;iii ABSTRACT OF THESIS EVALUATION OF ULTRASONIC SNOW DEPTH SENSORS FOR AUTOMATED SURFACE OBSERVING

  11. Impacts of Shortwave Penetration Depth on Large-Scale Ocean Circulation and Heat Transport

    E-Print Network [OSTI]

    Gnanadesikan, Anand

    Impacts of Shortwave Penetration Depth on Large-Scale Ocean Circulation and Heat Transport COLM independent parameter- izations that use ocean color to estimate the penetration depth of shortwave radiation. This study offers a way to evaluate the changes in irradiance penetration depths in coupled ocean

  12. Neutron production by cosmic-ray muons at shallow depth J. Busenitz,1

    E-Print Network [OSTI]

    Piepke, Andreas G.

    neutrino and proton decay experiments, as well as dark matter searches even though often at greater depth for cold dark matter 3 , and is presently at shallow depth; muon-induced neutrons repre- sent a major at a shallow depth of 32 meters of water equivalent has been measured. The Palo Verde neutrino detector

  13. Transition-fault test generation

    E-Print Network [OSTI]

    Cobb, Bradley Douglas

    2013-02-22T23:59:59.000Z

    . One way to detect these timing defects is to apply test patterns to the integrated circuit that are generated using the transition-fault model. Unfortunately, industry's current transition-fault test generation schemes produce test sets that are too...

  14. Calixarene supported transition metal clusters 

    E-Print Network [OSTI]

    Taylor, Stephanie Merac

    2013-06-29T23:59:59.000Z

    This thesis describes a series of calix[n]arene polynuclear transition metal and lanthanide complexes. Calix[4]arenes possess lower-rim polyphenolic pockets that are ideal for the complexation of various transition metal ...

  15. The energy transition Gerald Leach

    E-Print Network [OSTI]

    Kammen, Daniel M.

    The energy transition Gerald Leach The paper considers the substitution of tradition. The In the context of energy policy and planning, the paper concludes with a review of the reasons why transition. In the IS THE TRANSITION HAPPENING? poorest developing countries biomass fuels account for 60-95% of total energy use

  16. IDEA Reauthorized Statute SECONDARY TRANSITION

    E-Print Network [OSTI]

    IDEA ­ Reauthorized Statute SECONDARY TRANSITION (See also Individualized Education Program (IEP This document addresses only the changes to the IDEA provisions regarding secondary transition that took effect from the term "transition services" now refers to a "child" instead of a "student," The definition

  17. Radiative Transitions in Charmonium

    SciTech Connect (OSTI)

    Jozef Dudek; Robert Edwards; David Richards

    2005-10-01T23:59:59.000Z

    The form factors for the radiative transitions between charmonium mesons are investigated. We employ an anisotropic lattice using a Wilson gauge action, and domain-wall fermion action. We extrapolate the form factors to Q{sup 2} = 0, corresponding to a real photon, using quark-model-inspired functions. Finally, comparison is made with photocouplings extracted from the measured radiative widths, where known. Our preliminary results find photocouplings commensurate with these experimentally extracted values.

  18. Refrigerants in Transition

    E-Print Network [OSTI]

    Stouppe, D. E.

    .E. Senior Engineer The Hartford Steam Boiler Inspection and Insurance Company Hartford,. Connecticut ABSTRACT The massive growth of air conditioning and refrigeration has been a direct result of the development of a class of chemicals called fluorocarbons..., Gordon, "Forty Years Research on Atmospheric Ozone at Oxford: A !Iistory," Applied Optics, March t968, pp. 387-405. 4. Downing, R., "Development of Chloro fluorocarbon Refrigerants," CFCs: Time of Transition, ASHRAE Publication, Atlanta, GA, 1989...

  19. H{alpha} ABSORPTION IN TRANSITING EXOPLANET ATMOSPHERES

    SciTech Connect (OSTI)

    Christie, Duncan; Arras, Phil; Li Zhiyun, E-mail: dac5zm@virginia.edu, E-mail: pla7y@virginia.edu, E-mail: zl4h@virginia.edu [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States)

    2013-08-01T23:59:59.000Z

    Absorption of stellar H{alpha} by the upper atmosphere of the planet HD 189733b has recently been detected by Jensen et al. Motivated by this observation, we have developed a model for atomic hydrogen in the n = 2 state and compared the resulting H{alpha} line profile to the observations. The model atmosphere is in hydrostatic balance, as well as thermal and photoionization equilibrium. Collisional and radiative transitions are included in the determination of the n = 2 state level population. We find that H{alpha} absorption is dominated by an optical depth {tau} {approx} 1 shell, composed of hydrogen in the metastable 2s state that is located below the hydrogen ionization layer. The number density of the 2s state within the shell is found to vary slowly with radius, while that of the 1s state falls rapidly. Thus while the Ly{alpha} absorption, for a certain wavelength, occurs inside a relatively well defined impact parameter, the contribution to H{alpha} absorption is roughly uniform over the entire atomic hydrogen layer. The model can approximately reproduce the observed Ly{alpha} and H{alpha} integrated transit depths for HD 189733b by using an ionization rate enhanced over that expected for the star by an order of magnitude. For HD 209458b, we are unable to explain the asymmetric H{alpha} line profile observed by Jensen et al., as the model produces a symmetric line profile with transit depth comparable to that of HD 189733b. In an appendix, we study the effect of the stellar Ly{alpha} absorption on the net cooling rate.

  20. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2007-03-01T23:59:59.000Z

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  1. Analytic equivalence of geometric transitions

    E-Print Network [OSTI]

    Michele Rossi

    2014-08-28T23:59:59.000Z

    In this paper \\emph{analytic equivalence} of geometric transition is defined in such a way that equivalence classes of geometric transitions turn out to be the \\emph{arrows} of the \\cy web. Then it seems natural and useful, both from the mathematical and physical point of view, look for privileged arrows' representatives, called \\emph{canonical models}, laying the foundations of an \\emph{analytic} classification of geometric transitions. At this purpose a numerical invariant, called \\emph{bi--degree}, summarizing the topological, geometric and physical changing properties of a geometric transition, is defined for a large class of geometric transitions.

  2. Occlusion Analysis: Learning and Utilising Depth Maps in Object Tracking

    E-Print Network [OSTI]

    Jones, Graeme A.

    Thames, Surrey, KT1 2EE {d.greenhill,j.renno,j.orwell,g.jones}@kingston.ac.uk Abstract Complex scenes, turnstiles, barriers, etc. These structures induce partial occlusion which significantly distorts the ex

  3. Tritium research laboratory cleanup and transition project final report

    SciTech Connect (OSTI)

    Johnson, A.J.

    1997-02-01T23:59:59.000Z

    This Tritium Research Laboratory Cleanup and Transition Project Final Report provides a high-level summary of this project`s multidimensional accomplishments. Throughout this report references are provided for in-depth information concerning the various topical areas. Project related records also offer solutions to many of the technical and or administrative challenges that such a cleanup effort requires. These documents and the experience obtained during this effort are valuable resources to the DOE, which has more than 1200 other process contaminated facilities awaiting cleanup and reapplication or demolition.

  4. Impact of Phase Transitions on P Wave Velocities

    SciTech Connect (OSTI)

    D Weidner; L Li

    2011-12-31T23:59:59.000Z

    In regions where a high pressure phase is in equilibrium with a low pressure phase, the bulk modulus defined by the P-V relationship is greatly reduced. Here we evaluate the effect of such transitions on the P wave velocity. A model, where cation diffusion is the rate limiting factor, is used to project laboratory data to the conditions of a seismic wave propagating in the two-phase region. We demonstrate that for the minimum expected effect there is a significant reduction of the seismic velocity, as large as 10% over a narrow depth range.

  5. New framework hydrous silicate K{sub 3}Sc[Si{sub 3}O{sub 9}] {center_dot} H{sub 2}O related to the high-temperature anhydrous silicate K{sub 3}Ho[Si{sub 3}O{sub 9}] and symmetry analysis of a phase transition with prediction of structures

    SciTech Connect (OSTI)

    Belokoneva, E. L., E-mail: elbel@geol.msu.ru; Zorina, A. P.; Dimitrova, O. V. [Moscow State University, Faculty of Geology (Russian Federation)

    2013-07-15T23:59:59.000Z

    Crystals of a new framework silicate K{sub 3}Sc[Si{sub 3}O{sub 9}] {center_dot} H{sub 2}O, space group Pm2{sub 1}n (nonstandard setting of space group Pmn2{sub 1} = C{sub 2v}{sup 7}), are obtained under hydrothermal conditions. The structure is determined without preliminary knowledge of the chemical formula. The absolute configuration is determined. The structure is close to that of the high-temperature K{sub 3}Ho[Si{sub 3}O{sub 9}] phase, which was obtained upon the heating of K{sub 3}HoSi{sub 3}O{sub 8}(OH){sub 2}. This structural similarity is due to the specific conditions of synthesis and an analogous formula, where holmium is replaced by scandium. A symmetry analysis shows that the high local symmetry of a block (rod) is responsible for the first-order phase transition of both the order-disorder (OD) and displacement type. The number of structures in which the simplest and high-symmetry layers are multiplied by different symmetry elements are predicted.

  6. Galactic Bulge Microlensing Optical Depth from EROS-2

    E-Print Network [OSTI]

    C. Hamadache; L. Le Guillou; P. Tisserand; C. Afonso; J. N. Albert; J. Andersen; R. Ansari; E. Aubourg; P. Bareyre; J. P. Beaulieu; X. Charlot; C. Coutures; R. Ferlet; P. Fouqué; J. F. Glicenstein; B. Goldman; A. Gould; D. Graff; M. Gros; J. Haissinski; J. de Kat; E. Lesquoy; C. Loup; C. Magneville; J. B. Marquette; E. Maurice; A. Maury; A. Milsztajn; M. Moniez; N. Palanque-Delabrouille; O. Perdereau; Y. R. Rahal; J. Rich; M. Spiro; A. Vidal-Madjar; L. Vigroux; S. Zylberajch

    2006-07-13T23:59:59.000Z

    We present a new EROS-2 measurement of the microlensing optical depth toward the Galactic Bulge. Light curves of $5.6\\times 10^{6}$ clump-giant stars distributed over $66 \\deg^2$ of the Bulge were monitored during seven Bulge seasons. 120 events were found with apparent amplifications greater than 1.6 and Einstein radius crossing times in the range $5 {\\rm d}

  7. Transition Strategies: Government Options and Market Penetration...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Strategies: Government Options and Market Penetration Scenarios Transition Strategies: Government Options and Market Penetration Scenarios Presentation on Transition Strategies:...

  8. Transition Metal Switchable Mirror

    ScienceCinema (OSTI)

    None

    2010-01-08T23:59:59.000Z

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

  9. Transition Metal Switchable Mirror

    ScienceCinema (OSTI)

    None

    2013-05-29T23:59:59.000Z

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

  10. Superradiance Transition in Graphene

    E-Print Network [OSTI]

    Alexander I. Nesterov; Fermín Aceves de la Cruz; Valeriy A. Luchnikov; Gennady P. Berman

    2015-06-04T23:59:59.000Z

    We study theoretically and numerically the conditions required for the appearance of a superradiance transition in graphene. The electron properties of graphene are described in the single $p_z$-orbital tight-binding approximation, in which the model is reduced to the effective two-level pseudo-spin $1/2$ system. For each level we introduce the electron transfer rate of escape into a continuum. We demonstrate that, under some conditions, the superradiance experiences the maximal quantum coherent escape to the continuum.

  11. Transition Metal Switchable Mirror

    SciTech Connect (OSTI)

    None

    2009-01-01T23:59:59.000Z

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

  12. Transition Metal Switchable Mirror

    SciTech Connect (OSTI)

    2009-08-21T23:59:59.000Z

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

  13. Superradiance Transition in Graphene

    E-Print Network [OSTI]

    Alexander I. Nesterov; Fermín Aceves de la Cruz; Valeriy A. Luchnikov; Gennady P. Berman

    2015-06-12T23:59:59.000Z

    We study theoretically and numerically the conditions required for the appearance of a superradiance transition in graphene. The electron properties of graphene are described in the single $p_z$-orbital tight-binding approximation, in which the model is reduced to the effective two-level pseudo-spin $1/2$ system. For each level we introduce the electron transfer rate of escape into a continuum. We demonstrate that, under some conditions, the superradiance experiences the maximal quantum coherent escape to the continuum.

  14. 309 Building transition plan

    SciTech Connect (OSTI)

    Graves, C.E.

    1994-08-31T23:59:59.000Z

    The preparation for decontamination and decommissioning (transition) of the 309 Building is projected to be completed by the end of the fiscal year (FY) 1998. The major stabilization and decontamination efforts include the Plutonium Recycle Test Reactor (PRTR), fuel storage and transfer pits, Transfer Waste (TW) tanks and the Ion Exchange Vaults. In addition to stabilizing contaminated areas, equipment, components, records, waste products, etc., will be dispositioned. All nonessential systems, i.e., heating, ventilation, and air conditioning (HVAC), electrical, monitoring, fluids, etc., will be shut down and drained/de-energized. This will allow securing of the process, laboratory, and office areas of the facility. After that, the facility will be operated at a level commensurate with its surveillance needs while awaiting D&D. The implementation costs for FY 1995 through FY 1998 for the transition activities are estimated to be $1,070K, $2,115K, $2,939K, and $4,762K, respectively. Costs include an assumed company overhead of 20% and a 30% out year contingency.

  15. Phase transitions for N-electron atoms at the large-dimension limit Pablo Serra* and Sabre Kais

    E-Print Network [OSTI]

    Kais, Sabre

    that involve a nonzero latent heat and radical change of the structure of the material at the transition points. Second- order phase transitions are continuous phase changes where the properties of the system doPhase transitions for N-electron atoms at the large-dimension limit Pablo Serra* and Sabre Kais

  16. Comparison of bifurcation dynamics of turbulent transport models for the L-H transition

    SciTech Connect (OSTI)

    Weymiens, W., E-mail: w.weymiens@differ.nl; Blank, H. J. de; Hogeweij, G. M. D. [FOM Institute DIFFER—Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, PO Box 1207, Nieuwegein (Netherlands)] [FOM Institute DIFFER—Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, PO Box 1207, Nieuwegein (Netherlands); Paquay, S. [Department of Applied Physics, Eindhoven University of Technology, PO Box 503, Eindhoven (Netherlands)] [Department of Applied Physics, Eindhoven University of Technology, PO Box 503, Eindhoven (Netherlands)

    2014-05-15T23:59:59.000Z

    In more than three decades, a large amount of models and mechanisms have been proposed to describe a very beneficial feature of magnetically confined fusion plasmas: the L-H transition. Bifurcation theory can be used to compare these different models based on their dynamical transition structure. In this paper, we employ bifurcation theory to distinguish two fundamentally different descriptions of the interaction between turbulence levels and sheared flows. The analytic bifurcation analysis characterises the parameter space structure of the transition dynamics. Herewith, in these models three dynamically different types of transitions are characterised, sharp transitions, oscillatory transitions, and smooth transitions. One of the two models has a very robust transition structure and is therefore likely to be more accurate for such a robust phenomenon as the L-H transition. The other model needs more fine-tuning to get non-oscillatory transitions. These conclusions from the analytic bifurcation analysis are confirmed by dedicated numerical simulations, with the newly developed code Bifurcator.

  17. Practical Analysis of materials with depth varying compositions using FT-IR photoacoustic spectroscopy (PAS)

    SciTech Connect (OSTI)

    J.F. McClelland; R.W. Jones; Siquan Luo

    2004-09-30T23:59:59.000Z

    FT-IR photoacoustic spectroscopy (PAS) is discussed as a nondestructive method to probe the molecular composition of materials versus depth on the basis of the analysis of layers of experimentally controllable thickness, which are measured from the sample surface to depths of some tens of micrometers, depending on optical and thermal properties. Computational methods are described to process photoacoustic amplitude and phase spectra for both semi-quantitative and quantitative depth analyses. These methods are demonstrated on layered and gradient samples.

  18. Sea Ice Ridging and Rafting Structures: Is the microstructural controlled transition from Ductile to Brittle Behavior on Earth also seen on Mars? S.F. Ackley, P. Wagner, H. Xie,

    E-Print Network [OSTI]

    Texas at San Antonio, University of

    , and liquid brine contained within lamellae of a pure ice matrix in a closely interlocked structure. The relative amount of brine, ice and solid salts is controlled by the thermodynamics of the phase equilibrium]. At higher brine volumes, sea ice behaves as a ductile material, meaning that it can undergo large strain

  19. Structure and temperature-dependent phase transitions of lead-free Bi[subscript 1/2]Na[subscript 1/2]TiO[subscript 3]?Bi[subscript 1/2]K[subscript 1/2]TiO[subscript 3]?K[subscript 0.5]Na[subscript 0.5]NbO[subscript 3] piezoceramics

    SciTech Connect (OSTI)

    Anton, Eva-Maria; Schmitt, Ljubomira Ana; Hinterstein, Manuel; Trodahl, Joe; Kowalski, Ben; Jo, Wook; Kleebe, Hans-Joachim; Rödel, Jürgen; Jones, Jacob L. (TU Darmstadt) [TU Darmstadt; (VUW); (Florida)

    2014-05-28T23:59:59.000Z

    Structure and phase transitions of (1-y)((1-x)Bi{sub 1/2}Na{sub 1/2}TiO{sub 3}-xBi{sub 1/2}K{sub 1/2}TiO{sub 3})-yK{sub 0.5}Na{sub 0.5}NbO{sub 3} (x; y) piezoceramics (0.1 {le} x {le} 0.4; 0 {le} y {le} 0.05) were investigated by transmission electron microscopy, neutron diffraction, temperature-dependent x-ray diffraction, and Raman spectroscopy. The local crystallographic structure at room temperature (RT) does not change by adding K{sub 0.5}Na{sub 0.5}NbO{sub 3} to Bi{sub 1/2}Na{sub 1/2}TiO{sub 3}-xBi{sub 1/2}K{sub 1/2}TiO{sub 3} for x = 0.2 and 0.4. The average crystal structure and microstructure on the other hand develop from mainly long-range polar order with ferroelectric domains to short-range order with polar nanoregions displaying a more pronounced relaxor character. The (0.1; 0) and (0.1; 0.02) compositions exhibit monoclinic Cc space group symmetry, which transform into Cc + P4bm at 185 and 130 C, respectively. This high temperature phase is stable at RT for the morphotropic phase boundary compositions of (0.1; 0.05) and all compositions with x = 0.2. For the compositions of (0.1; 0) and (0.1; 0.02), local structural changes on heating are evidenced by Raman; for all other compositions, changes in the long-range average crystal structure were observed.

  20. Transition metal chemistry of main group hydrazides. 11. Synthesis and coordination chemistry of novel tetraphosphano phosphorinanes. X-ray crystal structure of [(W(CO){sub 4}){sub 2}({mu}-[PhPN(Me)N(P(OCH{sub 2}CF{sub 3}){sub 2})]{sub 2})

    SciTech Connect (OSTI)

    Reddy, V.S.; Katti, K.V.; Barnes, C.L. [Univ. of Missouri, Columbia, MO (United States)

    1995-03-01T23:59:59.000Z

    New main group compounds which can combine the reactivities of >P-N(R)-P< and also >P-N(R)-N(R)-P< frameworks in a single compound via a tetraphosphane network are important in the context of studying the coordination chemistry of multiphosphine ligands. The coordination chemistry of such multifunctional phosphanes may offer an important insight on the preferred mode of coordinations (viz., C vs D) and also provide unique opportunities for the construction of new bi- and multimetallic organometallic compounds. Herein, the authors report the first example of a novel tetraphosphane which contains both >P-N-P< and >P-N-N-P< functionalities in a cyclic network. The fundamental coordination chemistry of this new class of ligands is discussed in terms of its reactions with the group 6 transition metal carbonyl precursors and also through an X-ray crystal structure of a W(0) representative.

  1. High-energy x-ray diffractometer for nondestructive strain depth profile measurement

    SciTech Connect (OSTI)

    Al-Shorman, M. Y. [Department of Physics, Yarmouk University, 21163 Irbid (Jordan)] [Department of Physics, Yarmouk University, 21163 Irbid (Jordan); Jensen, T. C.; Gray, J. N. [Center for Nondestructive Evaluation, Iowa State University, Ames, Iowa 50011 (United States)] [Center for Nondestructive Evaluation, Iowa State University, Ames, Iowa 50011 (United States)

    2013-12-15T23:59:59.000Z

    We describe a lab-based high-energy x-ray diffraction system and a new approach to nondestructively measuring strain profiles in polycrystalline samples. This technique utilizes the tungsten K{sub ?1} characteristic radiation from a standard industrial x-ray tube. We introduce a simulation model that is used to determine strain values from data collected with this system. Examples of depth profiling are shown for shot peened aluminum and titanium samples. Profiles to 1 mm depth in aluminum and 300 ?m depth in titanium with a depth resolution of 20 ?m are presented.

  2. Depth Profile of Uncompensated Spins in an Exchange-Bias System

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Depth Profile of Uncompensated Spins in an Exchange-Bias System Print The phenomenon known as exchange bias at the interface between a ferromagnet and an antiferromagnet is...

  3. Terahertz spectroscopy of two-dimensional subwavelength plasmonic structures

    SciTech Connect (OSTI)

    Azad, Abul K [Los Alamos National Laboratory; Chen, Houtong [Los Alamos National Laboratory; Taylor, Antoinette [Los Alamos National Laboratory; O' Hara, John F [Los Alamos National Laboratory; Han, Jiaguang [OSU; Lu, Xinchao [OSU; Zhang, Weili [OSU

    2009-01-01T23:59:59.000Z

    The fascinating properties of plasmonic structures have had significant impact on the development of next generation ultracompact photonic and optoelectronic components. We study two-dimensional plasmonic structures functioning at terahertz frequencies. Resonant terahertz response due to surface plasmons and dipole localized surface plasmons were investigated by the state-of-the-art terahertz time domain spectroscopy (THz-TDS) using both transmission and reflection configurations. Extraordinary terahertz transmission was demonstrated through the subwavelength metallic hole arrays made from good conducting metals as well as poor metals. Metallic arrays m!lde from Pb, generally a poor metal, and having optically thin thicknesses less than one-third of a skin depth also contributed in enhanced THz transmission. A direct transition of a surface plasmon resonance from a photonic crystal minimum was observed in a photo-doped semiconductor array. Electrical controls of the surface plasmon resonances by hybridization of the Schottkey diode between the metallic grating and the semiconductor substrate are investigated as a function of the applied reverse bias. In addition, we have demonstrated photo-induced creation and annihilation of surface plasmons with appropriate semiconductors at room temperature. According to the Fano model, the transmission properties are characterized by two essential contributions: resonant excitation of surface plasmons and nonresonant direct transmission. Such plasmonic structures may find fascinating applications in terahertz imaging, biomedical sensing, subwavelength terahertz spectroscopy, tunable filters, and integrated terahertz devices.

  4. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2008-10-01T23:59:59.000Z

    This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

  5. Two glass transitions in miscible polymer blends?

    SciTech Connect (OSTI)

    Dudowicz, Jacek; Freed, Karl F. [The James Franck Institute and the Department of Chemistry, The University of Chicago, Chicago, Illinois 60637 (United States); Douglas, Jack F. [Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

    2014-06-28T23:59:59.000Z

    In contrast to mixtures of two small molecule fluids, miscible binary polymer blends often exhibit two structural relaxation times and two glass transition temperatures. Qualitative explanations postulate phenomenological models of local concentration enhancements due to chain connectivity in ideal, fully miscible systems. We develop a quantitative theory that explains qualitative trends in the dynamics of real miscible polymer blends which are never ideal mixtures. The theory is a synthesis of the lattice cluster theory of blend thermodynamics, the generalized entropy theory for glass-formation in polymer materials, and the Kirkwood-Buff theory for concentration fluctuations in binary mixtures.

  6. Optical pumping via incoherent Raman transitions

    E-Print Network [OSTI]

    A. D. Boozer; R. Miller; T. E. Northup; A. Boca; H. J. Kimble

    2007-10-04T23:59:59.000Z

    A new optical pumping scheme is presented that uses incoherent Raman transitions to prepare a trapped Cesium atom in a specific Zeeman state within the 6S_{1/2}, F=3 hyperfine manifold. An important advantage of this scheme over existing optical pumping schemes is that the atom can be prepared in any of the F=3 Zeeman states. We demonstrate the scheme in the context of cavity quantum electrodynamics, but the technique is equally applicable to a wide variety of atomic systems with hyperfine ground-state structure.

  7. Electronic, structural and magnetic studies of niobium borides of group 8 transition metals, Nb{sub 2}MB{sub 2} (M=Fe, Ru, Os) from first principles calculations

    SciTech Connect (OSTI)

    Touzani, Rachid St.; Fokwa, Boniface P.T., E-mail: Boniface.Fokwa@ac.rwth-aachen.de

    2014-03-15T23:59:59.000Z

    The Nb{sub 2}FeB{sub 2} phase (U{sub 3}Si{sub 2}-type, space group P4/mbm, no. 127) is known for almost 50 years, but until now its magnetic properties have not been investigated. While the synthesis of Nb{sub 2}OsB{sub 2} (space group P4/mnc, no. 128, a twofold superstructure of U{sub 3}Si{sub 2}-type) with distorted Nb-layers and Os{sub 2}-dumbbells was recently achieved, “Nb{sub 2}RuB{sub 2}” is still not synthesized and its crystal structure is yet to be revealed. Our first principles density functional theory (DFT) calculations have confirmed not only the experimental structures of Nb{sub 2}FeB{sub 2} and Nb{sub 2}OsB{sub 2}, but also predict “Nb{sub 2}RuB{sub 2}” to crystalize with the Nb{sub 2}OsB{sub 2} structure type. According to chemical bonding analysis, the homoatomic B–B interactions are optimized and very strong, but relatively strong heteroatomic M–B, B–Nb and M–Nb bonds (M=Fe, Ru, Os) are also found. These interactions, which together build a three-dimensional network, are mainly responsible for the structural stability of these ternary borides. The density-of-states at the Fermi level predicts metallic behavior, as expected, from metal-rich borides. Analysis of possible magnetic structures concluded preferred antiferromagnetic ordering for Nb{sub 2}FeB{sub 2}, originating from ferromagnetic interactions within iron chains and antiferromagnetic exchange interactions between them. -- Graphical abstract: Nb{sub 2}FeB{sub 2} (U{sub 3}Si{sub 2} structure type, space group P4/mbm, no. 127) is predicted to order antiferromagnetically, due to the presence of iron chains which show ferromagnetic interactions in the chains and antiferromagnetic interactions between them. “Nb{sub 2}RuB{sub 2}” is predicted to crystallize with the recently discovered Nb{sub 2}OsB{sub 2} twofold superstructure (space group P4/mnc, no. 128) of U{sub 3}Si{sub 2} structure type. The building of ruthenium dumbbells instead of chains along [001] is found to be responsible for the stabilization of this superstructure. Highlights: • Nb{sub 2}FeB{sub 2} is predicted to order antiferromagnetically. • Ferromagnetic interactions found in iron chains and antiferromagnetic ones between them. • Unknown “Nb{sub 2}RuB{sub 2}” predicted to crystallize with a twofold U{sub 3}Si{sub 2} superstructure. • Puckering of Nb-layer and Ru-dumbbell formation responsible for superstructure occurrence.

  8. Connecting Transitions in Galaxy Properties to Refueling

    E-Print Network [OSTI]

    Kannappan, Sheila J; Eckert, Kathleen D; Moffett, Amanda J; Wei, Lisa H; Pisano, D J; Baker, Andrew J; Vogel, Stuart N; Fabricant, Daniel G; Laine, Seppo; Norris, Mark A; Jogee, Shardha; Lepore, Natasha; Hough, Loren E; Weinberg-Wolf, Jennifer

    2013-01-01T23:59:59.000Z

    We relate transitions in galaxy structure and gas content to refueling, here defined to include both the external gas accretion and the internal gas processing needed to renew reservoirs for star formation. We analyze two z=0 data sets: a high-quality ~200-galaxy sample (the Nearby Field Galaxy Survey, data release herein) and a volume-limited ~3000-galaxy sample with reprocessed archival data. Both reach down to baryonic masses ~10^9Msun and span void-to-cluster environments. Two mass-dependent transitions are evident: (i) below the "gas-richness threshold" scale (V~125km/s), gas-dominated quasi-bulgeless Sd--Im galaxies become numerically dominant, while (ii) above the "bimodality" scale (V~200km/s), gas-starved E/S0s become the norm. Notwithstanding these transitions, galaxy mass (or V as its proxy) is a poor predictor of gas-to-stellar mass ratio M_gas/M_*. Instead, M_gas/M_* correlates well with the ratio of a galaxy's stellar mass formed in the last Gyr to its preexisting stellar mass, such that the two...

  9. Nanodisperse transition metal electrodes (NTME) for electrochemical cells

    DOE Patents [OSTI]

    Striebel, Kathryn A. (Oakland, CA); Wen, Shi-Jie (Sunnyvale, CA)

    2000-01-01T23:59:59.000Z

    Disclosed are transition metal electrodes for electrochemical cells using gel-state and solid-state polymers. The electrodes are suitable for use in primary and secondary cells. The electrodes (either negative electrode or positive electrode) are characterized by uniform dispersion of the transition metal at the nanoscale in the polymer. The transition metal moiety is structurally amorphous, so no capacity fade should occur due to lattice expansion/contraction mechanisms. The small grain size, amorphous structure and homogeneous distribution provide improved charge/discharge cycling performance, and a higher initial discharge rate capability. The cells can be cycled at high current densities, limited only by the electrolyte conductivity. A method of making the electrodes (positive and negative), and their usage in electrochemical cells are disclosed.

  10. Ferrofluid nucleus phase transitions in an external uniform magnetic field

    E-Print Network [OSTI]

    B. M. Tanygin; S. I. Shulyma; V. F. Kovalenko; M. V. Petrychuk

    2015-02-18T23:59:59.000Z

    Phase transition between massive dense phase and diluted superparamagnetic phase is studied by means of direct molecular dynamics simulation. Equilibrium structures of ferrofluid aggregate nucleus are obtained for different values of temperature and external magnetic field magnitude. For the ferrofluid phase diagram (coordinates "field-temperature"): approximate match of experiment and simulation is shown. Obtained phase coexistence curve has opposite trend compare to some of known theoretical results. This contradiction is related to postulating and comparing of the free energy of only simplest ferrofluid structures: diluted superparamagnetic phase, linear chains of the particles, and dense globes. The present results provide more fine structure of transition from "linear chains" to "dense globes" phase, e.g. through the ring assembly structure.

  11. Depth of cure and compressive strength of dental composites cured with blue light emitting diodes (LEDs)

    E-Print Network [OSTI]

    Ashworth, Stephen H.

    Depth of cure and compressive strength of dental composites cured with blue light emitting diodes with either a light emitting diode (LED) based light curing unit (LCU) or a conventional halogen LCU do reserved. Keywords: Blue light emitting diodes; Light curing unit; Composites; Irradiance; Spectrum; Depth

  12. Quantitative Depth Recovery from Time-Varying Optical Flow in a Kalman Filter

    E-Print Network [OSTI]

    Barron, John

    Quantitative Depth Recovery from Time-Varying Optical Flow in a Kalman Filter Framework John Barron Julich, 52425 Julich, Germany h.spies@fz-juelich.de Abstract. We present a Kalman lter framework, Depth from Optical Flow, Kalman Filter, 3D Camera Motion, Quantitative Error Analysis 1 Introduction We

  13. Method for determining depth and shape of a sub-surface conductive object

    DOE Patents [OSTI]

    Lee, D.O.; Montoya, P.C.; Wayland, Jr.

    1984-06-27T23:59:59.000Z

    The depth to and size of an underground object may be determined by sweeping a controlled source audio magnetotelluric (CSAMT) signal and locating a peak response when the receiver spans the edge of the object. The depth of the object is one quarter wavelength in the subsurface media of the frequency of the peak. 3 figures.

  14. Robust Head Pose Estimation by Fusing Time-of-Flight Depth and Color

    E-Print Network [OSTI]

    Wolberg, George

    . The key to our method is a model-based approach based on the fusion of color and time-of-flight depth data setup or knowledge of a pre-built model or training data. The use of additional depth data leads of user interaction, or controlling industrial machinery from a distance. Although many different systems

  15. Instruments and Methods Portable system for intermediate-depth ice-core drilling

    E-Print Network [OSTI]

    Howat, Ian M.

    Instruments and Methods Portable system for intermediate-depth ice-core drilling V. Zagorodnov, L Road, Columbus, Ohio 43210-1002, U.S.A. ABSTRACT. A lightweight, portable drilling system for coring up to 500 m depths has been developed and field-tested. The drilling system includes four major components

  16. The efficiency of depth discrimination for non-transparent and transparent stereoscopic surfaces

    E-Print Network [OSTI]

    Mamassian, Pascal

    The efficiency of depth discrimination for non-transparent and transparent stereoscopic surfaces investigate here how well human observers cope with stereo transparency by comparing their efficiency between transparent and opaque depth judgments. In two experiments, the efficiency measure was computed relative

  17. Computational model to evaluate port wine stain depth profiling using pulsed photothermal radiometry

    E-Print Network [OSTI]

    Choi, Bernard

    Computational model to evaluate port wine stain depth profiling using pulsed photothermal-thermal model to evaluate the use of pulsed photothermal radiometry (PPTR) for depth profiling of port wine the desired effect. A diagnostic measurement of the distribution of laser energy deposition and ensuing

  18. On the Symmetry Theory for Stokes Waves of Finite and In nite Depth

    E-Print Network [OSTI]

    Bath, University of

    function which satis#12;ed the correct kinematic and dynamic boundary conditions for water waves of steady water waves on ows with #12;nite depth. The inde- pendent variable was a periodic functionOn the Symmetry Theory for Stokes Waves of Finite and In#12;nite Depth J.F. Toland 1 Background

  19. A total of 377 peat age-depth relationships were used to quantify Holocene subsidence rates.

    E-Print Network [OSTI]

    Kulp, Mark

    A total of 377 peat age-depth relationships were used to quantify Holocene subsidence rates. Subsidence rates were calculated using peat ages calibrated to the sidereal time scale and burial depths a polynomial that relates the peat age to the position of sea-level at that time in the past. The "sea

  20. Filling holes in regional carbon budgets: Predicting peat depth in a north temperate lake district

    E-Print Network [OSTI]

    Turner, Monica G.

    Filling holes in regional carbon budgets: Predicting peat depth in a north temperate lake district] Peat deposits contain on the order of 1/6 of the Earth's terrestrial fixed carbon (C), but uncertainty in peat depth precludes precise estimates of peat C storage. To assess peat C in the Northern Highlands

  1. Prediction of end-depth ratio in open channels using genetic programming

    E-Print Network [OSTI]

    Fernandez, Thomas

    (EDR). Further effort is made to verify the applicability and superiority of this expressionD coefficient of determination EDR End-depth ratio (he/hc) GP Genetic Programming MRSS mean root of sum problem and to determine the end-depth ratio (EDR ¼ he/hc) in a wide range of channels. The Boussinesq

  2. Lower Bounds for Bounded Depth Frege Proofs via Pudlak-Buss Games

    E-Print Network [OSTI]

    Harsha, Prahladh

    19 Lower Bounds for Bounded Depth Frege Proofs via Pudl´ak-Buss Games ELI BEN-SASSON Technion. Our method uses the interpretation of proofs as two player games given by Pudl´ak and Buss. Our lower. 2010. Lower bounds for bounded depth Frege proofs via Pudl´ak- Buss games. ACM Trans. Comput. Logic, 11

  3. ESTIMATION OF SNOW ACCUMULATION IN ANTARCTICA USING AUTOMATED ACOUSTIC DEPTH GAUGE MEASUREMENTS

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    ESTIMATION OF SNOW ACCUMULATION IN ANTARCTICA USING AUTOMATED ACOUSTIC DEPTH GAUGE MEASUREMENTS microwave sounders, snow gauges, or radar are not feasible or not available in Antarctica at the present precipitation, remains largely unknown. Acoustic depth gauges (ADG) provide the only concrete real

  4. Structural and magnetic heterogeneities, phase transitions, and magnetoresistance and magnetoresonance properties of the composition ceramic La{sub 0.7}Pb{sub 0.3-x}Sn{sub x}MnO{sub 3}

    SciTech Connect (OSTI)

    Pashchenko, V. P., E-mail: alpash@mail.ru; Pashchenko, A. V.; Prokopenko, V. K.; Revenko, Yu. F.; Burkhovetskii, V. V.; Shemyakov, A. A. [National Academy of Sciences of Ukraine, Galkin Institute for Physics and Engineering (Ukraine); Sil'cheva, A. G. [Luhansk Taras Shevchenko National University (Ukraine); Levchenko, G. G. [National Academy of Sciences of Ukraine, Galkin Institute for Physics and Engineering (Ukraine)

    2012-03-15T23:59:59.000Z

    The La{sub 0.7}Pb{sub 0.3-x}Sn{sub x}MnO{sub 3} composition ceramic is studied by X-ray diffraction, resistive, magnetic, electron-microscopic, magnetoresistance, and NMR ({sup 55}Mn, {sup 139}La) methods. The substitution of tin for lead results in structural phase separation into the basic perovskite (R3-bar c) and spinell (Fd3m), phases: La{sub 0.7}Pb{sub 0.3-x}Sn{sub x}MnO{sub 3} {yields} La{sub 0.7-x}Pb{sub 0.3-x}MnO{sub 3} + 0.5xLa{sub 2}Sn{sub 2}O{sub 7}. Changes in the lattice parameter of the basic perovskite R3-bar c structure, the electrical resistivity, and the magnetic and magnetoresistance properties are caused by changes in the composition and content of a conducting perovskite ferromagnetic phase, the Mn{sup 3+}/Mn{sup 4+} ratio, and the imperfection of vacancy and cluster types. An in-plane nanostructured cluster is formed by Mn{sup 2+} ions located in distorted A-positions. The detected anomalous magnetic hysteresis is induced by the appearance of a unidirectional exchange anisotropy at the boundary of an in-plane antifer-romagnetic cluster coherently joined with a ferromagnetic matrix structure. The broad asymmetric NMR spectra of {sup 55}Mn and {sup 139}La indicate a high-frequency Mn{sup 3+} {r_reversible} Mn{sup 4+} superexchange and a nonuniform distribution of ions and defects. The constructed phase diagram characterizes a strong relation between the magnetic and transport properties in rare-earth manganites.

  5. Electronic structures of transition metal to hydrogen bonds: oxidative addition of dihydrogen to a square planar rhodium complex and quantum mechanical prediction of the geometry of a metal hydride

    E-Print Network [OSTI]

    Halpin, Carolyn F.

    1986-01-01T23:59:59.000Z

    and applications is dihydrogen or molecular hydrogen. Both the Heber process, in which nitrogen is converted to ammonia on an iron catalyst, and the Fischer-Tropsch synthesis, in which carbon monoxide is converted to hydrocarbons over iron and cobalt catalysts... systems containing hydride ligands. This work presents a computational method for examining the energetics and structures of two systems. The reaction RhC1(CO)(PHs)z + Hz ~ (H)zRhC1(CO)(PHs)z was examined to a~plain why the oxidation of RhCI(CO...

  6. Precision shooting: Sampling long transition pathways Michael Grnwald,1

    E-Print Network [OSTI]

    Gruenwald, Michael

    methods of transition path sampling to harvest simulated trajectories that exemplify such processes as autoionization in liquid water,5 structural transformations in nanocrystalline solids,6 and folding of small tools have been developed to extract from such a collection of trajecto- ries useful molecular

  7. Nonlinear Elasticity, Proteinquakes and the Energy Landscapes of Functional Transitions in Proteins

    E-Print Network [OSTI]

    Blanco, Philip R.

    Nonlinear Elasticity, Proteinquakes and the Energy Landscapes of Functional Transitions in Proteins. By generalizing the energy landscape theory of protein folding for biological functional events, we have developed becomes too high during the transition. (A) (B) (A) The residue strain energy as the structure is deformed

  8. Object Tracking and Multimedia Augmented Transition Network for Video Indexing and Modeling

    E-Print Network [OSTI]

    Chen, Shu-Ching

    Object Tracking and Multimedia Augmented Transition Network for Video Indexing and Modeling Shu, IN 47907 kashyap@ecn.purdue.edu Abstract In our previous work, a multimedia augmented transition network (ATN) model together with its multimedia input strings were proposed to model and structure video data

  9. Mantle transition zone beneath the Caribbean-South American plate boundary and its tectonic implications

    E-Print Network [OSTI]

    Niu, Fenglin

    Mantle transition zone beneath the Caribbean-South American plate boundary and its tectonic seismic network of Venezuela to study the mantle transition zone structure beneath the Caribbean Caribbean, the 410-km is featured by a narrow (200 km EW) 25-km uplift extending in the NS direction around

  10. Predicting dissolution patterns in variable aperture fractures: 1. Development and evaluation of an enhanced depth-averaged computational model

    SciTech Connect (OSTI)

    Detwiler, R L; Rajaram, H

    2006-04-21T23:59:59.000Z

    Water-rock interactions within variable-aperture fractures can lead to dissolution of fracture surfaces and local alteration of fracture apertures, potentially transforming the transport properties of the fracture over time. Because fractures often provide dominant pathways for subsurface flow and transport, developing models that effectively quantify the role of dissolution on changing transport properties over a range of scales is critical to understanding potential impacts of natural and anthropogenic processes. Dissolution of fracture surfaces is controlled by surface-reaction kinetics and transport of reactants and products to and from the fracture surfaces. We present development and evaluation of a depth-averaged model of fracture flow and reactive transport that explicitly calculates local dissolution-induced alterations in fracture apertures. The model incorporates an effective mass transfer relationship that implicitly represents the transition from reaction-limited dissolution to transport-limited dissolution. We evaluate the model through direct comparison to previously reported physical experiments in transparent analog fractures fabricated by mating an inert, transparent rough surface with a smooth single crystal of potassium dihydrogen phosphate (KDP), which allowed direct measurement of fracture aperture during dissolution experiments using well-established light transmission techniques [Detwiler, et al., 2003]. Comparison of experiments and simulations at different flow rates demonstrate the relative impact of the dimensionless Peclet and Damkohler numbers on fracture dissolution and the ability of the computational model to simulate dissolution. Despite some discrepancies in the small-scale details of dissolution patterns, the simulations predict the evolution of large-scale features quite well for the different experimental conditions. This suggests that our depth-averaged approach to simulating fracture dissolution provides a useful approach for extending laboratory results that are often limited in scale to scales that are more representative of geologic processes of interest.

  11. Core-Shell Structured Magnetic Ternary Nanocubes. | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structured Magnetic Ternary Nanocubes. Abstract: While transition metal-doped ferrite nanoparticles constitute an important class of soft magnetic nanomaterials with...

  12. Crossover transition in bag-like models

    E-Print Network [OSTI]

    Ferroni, Lorenzo

    2009-01-01T23:59:59.000Z

    DE-AC02-05CH11231 Crossover transition in bag-like models L.We show that a crossover transition qualitatively similar toI. INTRODUCTION The phase transition of strongly interacting

  13. Ising model: secondary phase transition

    E-Print Network [OSTI]

    You-gang Feng

    2012-04-09T23:59:59.000Z

    Lttice-spin phonons are considered, which make the heat capacity at the critical temperature satisfy experimental observations better. There is a BEC phase transition in an Ising model attributable to the lattice-spin phonons. We proved that the spin-wave theory only is available after BEC transition, and the magnons have the same characteristics as the lattice-spin phonons', resulting from quantum effect. Energy-level overlap effect at ultralow temperature is found. A prediction of BEC phase transition in a crystal is put forward as our theory generalization.

  14. Time Structure of Muonic Showers

    E-Print Network [OSTI]

    L. Cazon; R. A. Vazquez; A. A. Watson; E. Zas

    2003-11-10T23:59:59.000Z

    An analytical description of the time structure of the pulses induced by muons in air showers at ground level is deduced assuming the production distance distribution for the muons can be obtained elsewhere. The results of this description are compared against those obtained from simulated showers using AIRES. Major contributions to muon time delays are identified and a relation between the time structure and the depth distribution is unveiled.

  15. Observing the unfolding transition of [beta]-hairpin peptides with nonlinear infrared spectroscopy

    E-Print Network [OSTI]

    Smith, Adam Wilcox, 1977-

    2008-01-01T23:59:59.000Z

    The biological function of a protein is in large measure determined by its three-dimensional structure. To date, however, the transition of the protein between the native and non-native conformations is not well-understood. ...

  16. Vehicle Technologies Office: Transitioning the Transportation...

    Energy Savers [EERE]

    Transitioning the Transportation Sector - Exploring the Intersection of H2 Fuel Cell and Natural Gas Vehicles Vehicle Technologies Office: Transitioning the Transportation Sector -...

  17. Transition Strategies for 2006 and 2007

    Broader source: Energy.gov [DOE]

    Presentation on Transition Strategies given by Sigmund Gronich of the U.S. Department of Energy during the DOE Hydrogen Transition Analysis Workshop on January 26, 2006.

  18. Phase transition towards strange matter

    E-Print Network [OSTI]

    F. Gulminelli; Ad. R. Raduta; M. Oertel

    2012-08-31T23:59:59.000Z

    The phase diagram of a system constituted of neutrons and $\\Lambda$-hyperons in thermal equilibrium is evaluated in the mean-field approximation. It is shown that this simple system exhibits a complex phase diagram with first and second order phase transitions. Due to the generic presence of attractive and repulsive couplings, the existence of phase transitions involving strangeness appears independent of the specific interaction model. In addition we will show under which conditions a phase transition towards strange matter at high density exists, which is expected to persist even within a complete treatment including all the different strange and non- strange baryon states. The impact of this transition on the composition of matter in the inner core of neutron stars is discussed.

  19. Feeding the Transition Dairy Cow 

    E-Print Network [OSTI]

    Stokes, Sandra R.

    1999-09-20T23:59:59.000Z

    Proper nutrition management during a cow's transition period (from the last 3 weeks of gestation through the first 2 weeks of lactation), is critical to successful lactation. This publication gives details for nutrition management. Two charts list...

  20. Depth-resolved ultra-violet spectroscopic photo current-voltage measurements for the analysis of AlGaN/GaN high electron mobility transistor epilayer deposited on Si

    SciTech Connect (OSTI)

    Ozden, Burcu; Yang, Chungman; Tong, Fei; Khanal, Min P.; Mirkhani, Vahid; Sk, Mobbassar Hassan; Ahyi, Ayayi Claude; Park, Minseo, E-mail: park@physics.auburn.edu [Department of Physics, Auburn University, Auburn, Alabama 36849 (United States)

    2014-10-27T23:59:59.000Z

    We have demonstrated that the depth-dependent defect distribution of the deep level traps in the AlGaN/GaN high electron mobility transistor (HEMT) epi-structures can be analyzed by using the depth-resolved ultra-violet (UV) spectroscopic photo current-voltage (IV) (DR-UV-SPIV). It is of great importance to analyze deep level defects in the AlGaN/GaN HEMT structure, since it is recognized that deep level defects are the main source for causing current collapse phenomena leading to reduced device reliability. The AlGaN/GaN HEMT epi-layers were grown on a 6 in. Si wafer by metal-organic chemical vapor deposition. The DR-UV-SPIV measurement was performed using a monochromatized UV light illumination from a Xe lamp. The key strength of the DR-UV-SPIV is its ability to provide information on the depth-dependent electrically active defect distribution along the epi-layer growth direction. The DR-UV-SPIV data showed variations in the depth-dependent defect distribution across the wafer. As a result, rapid feedback on the depth-dependent electrical homogeneity of the electrically active defect distribution in the AlGaN/GaN HEMT epi-structure grown on a Si wafer with minimal sample preparation can be elucidated from the DR-UV-SPIV in combination with our previously demonstrated spectroscopic photo-IV measurement with the sub-bandgap excitation.

  1. Laboratory and field corrosion test results on aluminum-transition-steel systems on automobiles

    SciTech Connect (OSTI)

    Haynes, G.; Baboian, R. [Texas Instruments Inc., Attleboro, MA (United States). Electrochemical and Corrosion Lab.

    1995-11-01T23:59:59.000Z

    Use of steel clad aluminum transition material to join aluminum body panels and structural members to steel is demonstrated. The transition material allows joining of aluminum and steel by conventional techniques such as spot welding and eliminates galvanic corrosion at the joints. Corrosion test results for a wide range of aluminum-transition-steel systems in laboratory tests, atmospheric exposure, and field test plates are presented. The break strength of joints containing two, three, or four members was used as a measure of performance after corrosion testing. Statistical analysis of the results showed that the transition material prevented degradation of the mechanical properties of the joints.

  2. Influence of a local change of depth on the behavior of bouncing oil drops

    E-Print Network [OSTI]

    Carmigniani, Remi; Symon, Sean; McKeon, Beverley J

    2013-01-01T23:59:59.000Z

    The work of Couder \\textit{et al} (see also Bush \\textit{et al}) inspired consideration of the impact of a submerged obstacle, providing a local change of depth, on the behavior of oil drops in the bouncing regime. In the linked videos, we recreate some of their results for a drop bouncing on a uniform depth bath of the same liquid undergoing vertical oscillations just below the conditions for Faraday instability, and show a range of new behaviors associated with change of depth. This article accompanies a fluid dynamics video entered into the Gallery of Fluid Motion of the 66th Annual Meeting of the APS Division of Fluid Dynamics.

  3. Measurement of the atmospheric muon depth intensity relation with the NEMO Phase-2 tower

    E-Print Network [OSTI]

    S. Aiello; F. Ameli; M. Anghinolfi; G. Barbarino; E. Barbarito; F. Barbato; N. Beverini; S. Biagi; B. Bouhadef; C. Bozza; G. Cacopardo; M. Calamai; C. Calì; A. Capone; F. Caruso; A. Ceres; T. Chiarusi; M. Circella; R. Cocimano; R. Coniglione; M. Costa; G. Cuttone; C. D'Amato; A. D'Amico; G. De Bonis; V. De Luca; N. Deniskina; G. De Rosa; F. Di Capua; C. Distefano; P. Fermani; L. A. Fusco; F. Garufi; V. Giordano; A. Gmerk; R. Grasso; G. Grella; C. Hugon; M. Imbesi; V. Kulikovskiy; G. Larosa; D. Lattuada; K. P. Leismueller; E. Leonora; P. Litrico; A. Lonardo; F. Longhitano; D. Lo Presti; E. Maccioni; A. Margiotta; A. Martini; R. Masullo; P. Migliozzi; E. Migneco; A. Miraglia; C. M. Mollo; M. Mongelli; M. Morganti; P. Musico; M. Musumeci; C. A. Nicolau; A. Orlando; R. Papaleo; C. Pellegrino; M. G. Pellegriti; C. Perrina; P. Piattelli; C. Pugliatti; S. Pulvirenti; A. Orselli; F. Raffaelli; N. Randazzo; G. Riccobene; A. Rovelli; M. Sanguineti; P. Sapienza; V. Sciacca; I. Sgura; F. Simeone; V. Sipala; F. Speziale; M. Spina; A. Spitaleri; M. Spurio; S. M. Stellacci; M. Taiuti; G. Terreni; L. Trasatti; A. Trovato; C. Ventura; P. Vicini; S. Viola; D. Vivolo

    2014-12-03T23:59:59.000Z

    The results of the analysis of the data collected with the NEMO Phase-2 tower, deployed at 3500 m depth about 80 km off-shore Capo Passero (Italy), are presented. Cherenkov photons detected with the photomultipliers tubes were used to reconstruct the tracks of atmospheric muons. Their zenith-angle distribution was measured and the results compared with Monte Carlo simulations. An evaluation of the systematic effects due to uncertainties on environmental and detector parameters is also included. The associated depth intensity relation was evaluated and compared with previous measurements and theoretical predictions. With the present analysis, the muon depth intensity relation has been measured up to 13 km of water equivalent.

  4. Transition between Two Oscillation Modes

    E-Print Network [OSTI]

    Ricardo Lopez-Ruiz; Yves Pomeau

    2002-05-17T23:59:59.000Z

    A model for the symmetric coupling of two self-oscillators is presented. The nonlinearities cause the system to vibrate in two modes of different symmetries. The transition between these two regimes of oscillation can occur by two different scenarios. This might model the release of vortices behind circular cylinders with a possible transition from a symmetric to an antisymmetric Benard-von Karman vortex street.

  5. Exciton complexes in low dimensional transition metal dichalcogenides

    SciTech Connect (OSTI)

    Thilagam, A., E-mail: thilaphys@gmail.com [Information Technology, Engineering and Environment, University of South Australia, Adelaide 5095 (Australia)

    2014-08-07T23:59:59.000Z

    We examine the excitonic properties of layered configurations of low dimensional transition metal dichalcogenides (LTMDCs) using the fractional dimensional space approach. The binding energies of the exciton, trion, and biexciton in LTMDCs of varying layers are analyzed, and linked to the dimensionality parameter ?, which provides insight into critical electro-optical properties (relative oscillator strength, absorption spectrum, exciton-exciton interaction) of the material systems. The usefulness of ? is highlighted by its independence of the physical mechanisms underlying the confinement effects of geometrical structures. Our estimates of the binding energies of exciton complexes for the monolayer configuration of transition metal dichalcogenides suggest a non-collinear structure for the trion and a positronium-molecule-like square structure for the biexciton.

  6. Improved foilless Ku-band transit-time oscillator for generating gigawatt level microwave with low guiding magnetic field

    SciTech Connect (OSTI)

    Ling, Junpu; He, Juntao, E-mail: hejuntao12@163.com; Zhang, Jiande; Jiang, Tao; Hu, Yi [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2014-09-15T23:59:59.000Z

    An improved foilless Ku-band transit-time oscillator with low guiding magnetic field is proposed and investigated in this paper. With a non-uniform buncher and a coaxial TM{sub 02} mode dual-resonant reflector, this improved device can output gigawatt level Ku-band microwave with relatively compact radial dimensions. Besides the above virtue, this novel reflector also has the merits of high TEM reflectance, being more suitable for pre-modulating the electron beam and enhancing the conversion efficiency. Moreover, in order to further increase the conversion efficiency and lower the power saturation time, a depth-tunable coaxial collector and a resonant cavity located before the extractor are employed in our device. Main structure parameters of the device are optimized by particle in cell simulations. The typical simulation result is that, with a 380?kV, 8.2?kA beam guided by a magnetic field of about 0.6?T, 1.15?GW microwave pulse at 14.25?GHz is generated, yielding a conversion efficiency of about 37%.

  7. Risk assessment and evaluation of the conductor setting depth in shallow water, Gulf of Mexico 

    E-Print Network [OSTI]

    Tu, Yong B.

    2006-08-16T23:59:59.000Z

    Factors related to operations of a well that impact drilling uncertainties in the shallow water region of the Gulf of Mexico (GOM) can be directly linked to the site specific issues; such as water depth and local geological ...

  8. Influence of planting depth on landscape establishment of container-grown trees

    E-Print Network [OSTI]

    Bryan, Donita Lynn

    2009-05-15T23:59:59.000Z

    and productivity (sustainability) of trees within terrestrial ecosystems. Tree planting depth, i.e. location of the root collar relative to soil grade, is of particular concern for tree growth, development, and performance in the landscape. A series of model...

  9. Use of Rapid Temperature Measurements at a 2-Meter Depth to Augment...

    Open Energy Info (EERE)

    Temperature Gradient Drilling Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Use of Rapid Temperature Measurements at a 2-Meter Depth to...

  10. Depth inversion for nonlinear waves shoaling over a barred-beach 1

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    and calibrated for mild slopes are applied to the barred-beach. Expectedly, errors on depth prediction occur techniques such as Synthetic Aperture Radar (SAR), are still quite problematic under the current state

  11. Bioluminescence in a complex coastal environment: 2. Prediction of bioluminescent source depth from spectral

    E-Print Network [OSTI]

    Moline, Mark

    of a passive method (as opposed to active methods such as RADAR or LIDAR) to identify hostile ships, submarines this relative importance [Nealson, 1993]. Therefore the depth distribution of bioluminescent organisms is of eco

  12. PROOF COMPLEXITY IN ALGEBRAIC SYSTEMS AND BOUNDED DEPTH FREGE SYSTEMS WITH

    E-Print Network [OSTI]

    Krajíèek, Jan

    PROOF COMPLEXITY IN ALGEBRAIC SYSTEMS AND BOUNDED DEPTH FREGE SYSTEMS WITH MODULAR COUNTING S. Buss; 2 S. Buss et al. NP 6= coNP . Despite extensive research (see the expository articles Buss (1995b

  13. Vehicle Technologies Office Merit Review 2014: Advanced Technology Vehicle Lab Benchmarking- Level 2 (in-depth)

    Broader source: Energy.gov [DOE]

    Presentation given by Argonne National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about level 2 (in-depth...

  14. Temperature-dependent phase transitions of a complex biological membrane in zeptoliter volumes

    SciTech Connect (OSTI)

    Nikiforov, Maxim [ORNL; Hohlbauch, Sophia [Asylum Research, Santa Barbara, CA; King, William P [University of Illinois, Urbana-Champaign; Voitchovsky, K [Massachusetts Institute of Technology (MIT); Contera, S Antoranz [University of Oxford; Jesse, Stephen [ORNL; Kalinin, Sergei V [ORNL; Proksch, Roger [Asylum Research, Santa Barbara, CA

    2011-01-01T23:59:59.000Z

    Phase transitions in purple membrane have been a topic of debate for the past two decades. In this work we present studies of a reversible transition of purple membrane in the 50 60 C range in zeptoliter volumes under different heating regimes (global heating and local heating). The temperature of the reversible phase transition is 52 5 C for both local and global heating, supporting the hypothesis that this transition is mainly due to a structural rearrangement of bR molecules and trimers. To achieve high resolution measurements of temperature-dependent phase transitions, a new scanning probe microscopy-based method was developed. We believe that our new technique can be extended to other biological systems and can contribute to the understanding of inhomogeneous phase transitions in complex systems.

  15. Partnering: an in-depth comparison of its elements to quality improvement principles

    E-Print Network [OSTI]

    Lozada, Anthony David

    1992-01-01T23:59:59.000Z

    PARTNERING: AN IN-DEPTH COMPARISON OF ITS ELEMENTS TO QUALITY IMPROVEMENT PRINCIPLES A Thesis by ANTHONY DAVID LOZADA Submitted to the Office of Graduate Studies of Texas AIIrM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE December 1992 Major Subject: Civil Engineering PARTNERING: AN IN-DEPTH COMPARISON OF ITS ELEMENTS TO QUALITY IMPROVEMENT PRINCIPLES A Thesis by ANTHONY DAVID LOZADA Approved as to style and content by: Donald A...

  16. Pressure driven spin crossover and isostructural phase transition in LaFeO{sub 3}

    SciTech Connect (OSTI)

    Javaid, Saqib [EMMG, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); National Centre of Physics, Islamabad (Pakistan); Javed Akhtar, M., E-mail: javedakhtar6@gmail.com; Younas, Muhammad [EMMG, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); Ahmad, Irfan [EMMG, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); DMME, Pakistan Institute of Engineering and Applied Sciences, Nilore, Islamabad (Pakistan); Shah, Shafqat H. [Theoretical Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); Ahmad, Iftikhar [Department of Physics, University of Malakand, Chakdara (Pakistan)

    2013-12-28T23:59:59.000Z

    We have studied the behavior of LaFeO{sub 3} under pressure (P) using density functional theory (DFT) and atomistic simulations. Ground state structural properties of LaFeO{sub 3} are correctly described by atomistic simulations. The effect of high pressure shows that there is an isotropic compression up to 100?GPa. However, DFT calculations show that within pressure range 0?structure. On the other hand, at P ?32.4?GPa high to low spin magnetic phase transition is observed, which is accompanied by 6.9% volume collapse of LaFeO{sub 3} unit cell, while retaining the ground state orthorhombic crystal structure, i.e., isostructural phase transition. Furthermore, the band gap is closed leading insulator to metal transition. This differing behavior observed by the two techniques can be attributed to the omission of magnetic effects in static simulations. The simultaneous magnetic, electrical, and structural (volume collapse) phase transitions of LaFeO{sub 3} under compression as revealed by DFT calculations corroborate experimental findings. From these results, we can elaborate the mechanism of phase transition in LaFeO{sub 3}: increasing crystal field induces a high spin to low spin transition, which in turn drives the electrical transitions and volume collapse.

  17. Transition Path Theory E. Vanden-Eijnden

    E-Print Network [OSTI]

    Van Den Eijnden, Eric

    Transition Path Theory E. Vanden-Eijnden Courant Institute of Mathematical Sciences, New York University New York, NY 10012 eve2cims.nyu.edu Eric Vanden-Eijnden E. Vanden-Eijnden: Transition Path Theory of the Current and Transition Tubes . . . . . . . . . . . . . . . . . . . . . . 451 5 Comparison with Transition

  18. 12 August 2005 Observing Optical Transition

    E-Print Network [OSTI]

    Anlage, Steven

    12 August 2005 Observing Optical Transition Radiation from 10keV Electrons 1 #12;12 August 2005 Observing Optical Transition Radiation from 10keV Electrons 2 #12;12 August 2005 Observing Optical Transition Radiation from 10keV Electrons 3 #12;12 August 2005 Observing Optical Transition Radiation from 10

  19. Regional Transit System: Return on Investment Assessment

    E-Print Network [OSTI]

    Minnesota, University of

    Regional Transit System: Return on Investment Assessment May 2014 #12;1 Today's agenda Itasca transit options Enables strategic, efficient investment in long-term infrastructure, e.g., energy grid are seeking cities with good transit Transit can be a cost-efficient way to add capacity in corridors

  20. Non-destructive in-situ method and apparatus for determining radionuclide depth in media

    DOE Patents [OSTI]

    Xu, X. George (Clifton Park, NY); Naessens, Edward P. (West Point, NY)

    2003-01-01T23:59:59.000Z

    A non-destructive method and apparatus which is based on in-situ gamma spectroscopy is used to determine the depth of radiological contamination in media such as concrete. An algorithm, Gamma Penetration Depth Unfolding Algorithm (GPDUA), uses point kernel techniques to predict the depth of contamination based on the results of uncollided peak information from the in-situ gamma spectroscopy. The invention is better, faster, safer, and/cheaper than the current practice in decontamination and decommissioning of facilities that are slow, rough and unsafe. The invention uses a priori knowledge of the contaminant source distribution. The applicable radiological contaminants of interest are any isotopes that emit two or more gamma rays per disintegration or isotopes that emit a single gamma ray but have gamma-emitting progeny in secular equilibrium with its parent (e.g., .sup.60 Co, .sup.235 U, and .sup.137 Cs to name a few). The predicted depths from the GPDUA algorithm using Monte Carlo N-Particle Transport Code (MCNP) simulations and laboratory experiments using .sup.60 Co have consistently produced predicted depths within 20% of the actual or known depth.

  1. Measurement of sound speed vs. depth in South Pole ice: pressure waves and shear waves

    SciTech Connect (OSTI)

    IceCube Collaboration; Klein, Spencer

    2009-06-04T23:59:59.000Z

    We have measured the speed of both pressure waves and shear waves as a function of depth between 80 and 500 m depth in South Pole ice with better than 1% precision. The measurements were made using the South Pole Acoustic Test Setup (SPATS), an array of transmitters and sensors deployed in the ice at the South Pole in order to measure the acoustic properties relevant to acoustic detection of astrophysical neutrinos. The transmitters and sensors use piezoceramics operating at {approx}5-25 kHz. Between 200 m and 500 m depth, the measured profile is consistent with zero variation of the sound speed with depth, resulting in zero refraction, for both pressure and shear waves. We also performed a complementary study featuring an explosive signal propagating vertically from 50 to 2250 m depth, from which we determined a value for the pressure wave speed consistent with that determined for shallower depths, higher frequencies, and horizontal propagation with the SPATS sensors. The sound speed profile presented here can be used to achieve good acoustic source position and emission time reconstruction in general, and neutrino direction and energy reconstruction in particular. The reconstructed quantities could also help separate neutrino signals from background.

  2. Infrared photocarrier radiometry of semiconductors: Physical principles, quantitative depth profilometry, and scanning imaging of deep subsurface electronic defects

    E-Print Network [OSTI]

    Mandelis, Andreas

    - sorption of the incident beam and nonradiative heating. The PCR theory is presented as infrared depthInfrared photocarrier radiometry of semiconductors: Physical principles, quantitative depth May 2003 Laser-induced infrared photocarrier radiometry PCR is introduced theoretically

  3. Relationships between inherent optical properties and the depth of penetration of solar radiation in optically complex coastal waters

    E-Print Network [OSTI]

    Strathclyde, University of

    Relationships between inherent optical properties and the depth of penetration of solar radiation optical properties and the depth of penetration of solar radiation in optically complex coastal waters, J

  4. Rounding of the localization transition in model porous media

    E-Print Network [OSTI]

    Simon K. Schnyder; Markus Spanner; Felix Höfling; Thomas Franosch; Jürgen Horbach

    2014-11-07T23:59:59.000Z

    The generic mechanisms of anomalous transport in porous media are investigated by computer simulations of two-dimensional model systems. In order to bridge the gap between the strongly idealized Lorentz model and realistic models of porous media, two models of increasing complexity are considered: a cherry-pit model with hard-core correlations as well as a soft-potential model. An ideal gas of tracer particles inserted into these structures is found to exhibit anomalous transport which extends up to several decades in time. Also, the self-diffusion of the tracers becomes suppressed upon increasing the density of the systems. These phenomena are attributed to an underlying percolation transition. In the soft potential model the transition is rounded, since each tracer encounters its own critical density according to its energy. Therefore, the rounding of the transition is a generic occurrence in realistic, soft systems.

  5. A phase transition in commuting Gaussian multi-matrix models

    E-Print Network [OSTI]

    Ofer Aharony; Sean A. Hartnoll

    2007-07-02T23:59:59.000Z

    We analyze in detail a second order phase transition that occurs in large N Gaussian multi-matrix models in which the matrices are constrained to be commuting. The phase transition occurs as the relative masses of the matrices are varied, assuming that there are at least four matrices in the lowest mass level. We also discuss the phase structure of weakly coupled large N 3+1 dimensional gauge theories compactified on a three-sphere of radius R. We argue that these theories are well described at high temperatures (T >> 1/R) by a Gaussian multi-matrix model, and that they do not exhibit any phase transitions between the deconfinement scale (T ~ 1/R) and the scale where perturbation theory breaks down (T ~ 1 / \\lambda R, where \\lambda is the 't Hooft coupling).

  6. Measuring Cost Variability in Provision of Transit Service

    E-Print Network [OSTI]

    Taylor, Brian D.; Garrett, Mark; Iseki, Hiroyuki

    2010-01-01T23:59:59.000Z

    Comprehensive Transit Performance Indicators. UCTC WorkingModal Transit Performance Indicators. Ph.D. dissertation.

  7. An Information And Institutional Inventory Of California Transit Agencies

    E-Print Network [OSTI]

    Hickman, Mark; Day, Theodore

    1996-01-01T23:59:59.000Z

    Salinas Transit 1 Ryan Ranch Road Monterey CA 93940 Jim Andrew, Interim Transit Manager Morongo Basin

  8. ARM: 10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Newsom, Rob; Goldsmith, John

    10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

  9. Quark condensates and the deconfinement transition

    E-Print Network [OSTI]

    Christian S. Fischer; Jens A. Mueller

    2009-08-18T23:59:59.000Z

    In this talk we present results on the chiral and the deconfinement transition of quenched QCD from Dyson-Schwinger equations. We determine the ordinary quark condensate signaling the chiral transition and the dual quark condensate signaling the deconfinement transition from the Landau gauge quark propagator evaluated at generalized boundary conditions. We find only slightly different transition temperatures at finite quark masses, whereas the transition temperatures coincide in the chiral limit.

  10. Prospects for river discharge and depth estimation through assimilation of swath-altimetry into a raster-based hydrodynamics

    E-Print Network [OSTI]

    Howat, Ian M.

    Prospects for river discharge and depth estimation through assimilation of swath water depth and discharge, reducing the discharge RMSE from 23.2% to 10.0% over an 84-day simulation. Clark, D. P. Lettenmaier, and D. E. Alsdorf (2007), Prospects for river discharge and depth estimation

  11. Adhesion Transition of Flexible Sheets

    E-Print Network [OSTI]

    Arthur A. Evans; Eric Lauga

    2009-05-31T23:59:59.000Z

    Intermolecular forces are known to precipitate adhesion events between solid bodies. Inspired by a macro-scale experiment showing the hysteretic adhesion of a piece of flexible tape over a plastic substrate, we develop here a model of far-field dry adhesion between two flexible sheets interacting via a power-law potential. We show that phase transitions from unadhered to adhered states occur as dictated by a dimensionless bending parameter representing the ratio of interaction strength to bending stiffness. The order of the adhesion transitions, as well as their hysteretic nature, is shown to depend on the form of the interaction potential between the flexible sheets. When three or more sheets interact, additional geometrical considerations determine the hierarchical or sequential nature of the adhesion transitions.

  12. Effects of cavern depth on surface subsidence and storage loss of oil-filled caverns

    SciTech Connect (OSTI)

    Hoffman, E L

    1992-01-01T23:59:59.000Z

    Finite element analyses of oil-filled caverns were performed to investigate the effects of cavern depth on surface subsidence and storage loss, a primary performance criteria of SPR caverns. The finite element model used for this study was axisymmetric, approximating an infinite array of caverns spaced at 750 ft. The stratigraphy and cavern size were held constant while the cavern depth was varied between 1500 ft and 3000 ft in 500 ft increments. Thirty year simulations, the design life of the typical SPR cavern, were performed with boundary conditions modeling the oil pressure head applied to the cavern lining. A depth dependent temperature gradient of 0.012{degrees}F/ft was also applied to the model. The calculations were performed using ABAQUS, a general purpose of finite element analysis code. The user-defined subroutine option in ABAQUS was used to enter an elastic secondary creep model which includes temperature dependence. The calculations demonstrated that surface subsidence and storage loss rates increase with increasing depth. At lower depths the difference between the lithostatic stress and the oil pressure is greater. Thus, the effective stresses are greater, resulting in higher creep rates. Furthermore, at greater depths the cavern temperatures are higher which also produce higher creep rates. Together, these factors result in faster closure of the cavern. At the end of the 30 year simulations, a 1500 ft-deep cavern exhibited 4 percent storage loss and 4 ft of subsidence while a 3000 ft-deep cavern exhibited 33 percent storage loss and 44 ft of subsidence. The calculations also demonstrated that surface subsidence is directly related to the amount of storage loss. Deeper caverns exhibit more subsidence because the caverns exhibit more storage loss. However, for a given amount of storage loss, nearly the same magnitude of surface subsidence was exhibited, independent of cavern depth.

  13. Finding Transition Pathways on Manifolds

    E-Print Network [OSTI]

    Tiejun Li; Xiaoguang Li; Xiang Zhou

    2014-08-13T23:59:59.000Z

    We consider noise-induced transition paths in randomly perturbed dynami- cal systems on a smooth manifold. The classical Freidlin-Wentzell large devia- tion theory in Euclidean spaces is generalized and new forms of action functionals are derived in the spaces of functions and the space of curves to accommodate the intrinsic constraints associated with the manifold. Numerical meth- ods are proposed to compute the minimum action paths for the systems with constraints. The examples of conformational transition paths for a single and double rod molecules arising in polymer science are numerically investigated.

  14. Depth distribution of lithium in oxidized binary Al-Li alloys determined by secondary ion mass spectrometry and neutron depth profiling

    SciTech Connect (OSTI)

    Soni, K.K. (Univ. of Chicago, IL (United States)); Williams, D.B. (Lehigh Univ., Bethlehem, PA (United States)); Newbury, D.E.; Chi, P.; Downing, R.G.; Lamaza, G. (National Inst. of Standards and Technology, Gaithersburg, MD (United States))

    1993-01-01T23:59:59.000Z

    Oxidation of binary Al-Li alloys during short exposures at 530 C and long exposures at 200 C was studied with regard to the Li distribution. Secondary ion mass spectrometry (SIMS) and neutron depth profiling (NDP) were used to obtain quantitative Li depth profiles across the surface oxide layer and the underlying alloy. The underlying alloy was depleted in Li as a result of oxidation at 530 and 200 C. The SIMS and NDP results showed good mutual agreement and were used to evaluate the oxide thickness, the Li concentration at the oxide-ally interface, and the mass balance between oxide and alloy. The Li depletion profiles in the alloy were also calculated using the interdiffusion coefficients reported in the literature and compared with the measured profiles; the two profiles differed at 530 C but showed good agreement at 200 C.

  15. Experimental investigation of welding penetration-depth in high-purity aluminium

    SciTech Connect (OSTI)

    Tong, W. [Babcock and Wilcox, Lynchburg, VA (United States). Naval Nuclear Fuel Div.

    1996-12-31T23:59:59.000Z

    One of the most important parameters in the superconducting splice design is the welding penetration-depth because it determines the electrical resistivity across the welded joints through the high-purity aluminum stabilizers. Highly resistive welds could lead to conductor instability when the superconductor goes normal. In the present investigation, experiments were performed using gas tungsten-arc welding to identify the effects of the welding parameters on the penetration-depth. The experimental results will be applied to the optimization of the superconducting splice design. The mock-up test data and theoretical analysis have shown that the higher energy input and lower welding speed produce the deeper penetration-depth in high-purity aluminum. In order to achieve an approximately uniform penetration-depth, three methods were explored: (i) a starting-delay at the welding start point, (ii) an external cooling, and (iii) staggered overlapping weldments. The experimental results have suggested that a uniform penetration-depth can be obtained under the thermal equilibrium welding conditions.

  16. Cluster states and isoscalar monopole transitions of $^{24}$Mg

    E-Print Network [OSTI]

    Chiba, Y

    2015-01-01T23:59:59.000Z

    We investigate structure of the excited $0^+$ states of $^{24}$Mg populated by isoscalar monopole transition from the ground state on the basis of antisymmetrized molecular dynamics calculation with Gogny D1S interaction. The calculated isoscalar monopole strength function shows reasonable agreement with experiment and is consistent with other theoretical calculation. The structure of the excited $0^+$ states with pronounced isoscalar monopole transitions are analyzed. It is found that the $0^+_2$, $0^+_3$ and $0^+_5$ states have mixed nature of mean-field and cluster, and that the $0^+_8$ state is dominated by $^{12}$C+$^{12}$C cluster configuration. In addition, it is predicted that $5\\alpha$-pentagon+$\\alpha$ states appear around 23 MeV.

  17. Cluster states and isoscalar monopole transitions of $^{24}$Mg

    E-Print Network [OSTI]

    Y. Chiba; M. Kimura

    2015-02-23T23:59:59.000Z

    We investigate structure of the excited $0^+$ states of $^{24}$Mg populated by isoscalar monopole transition from the ground state on the basis of antisymmetrized molecular dynamics calculation with Gogny D1S interaction. The calculated isoscalar monopole strength function shows reasonable agreement with experiment and is consistent with other theoretical calculation. The structure of the excited $0^+$ states with pronounced isoscalar monopole transitions are analyzed. It is found that the $0^+_2$, $0^+_3$ and $0^+_5$ states have mixed nature of mean-field and cluster, and that the $0^+_8$ state is dominated by $^{12}$C+$^{12}$C cluster configuration. In addition, it is predicted that $5\\alpha$-pentagon+$\\alpha$ states appear around 23 MeV.

  18. JOURNAL DE PHYSIQUE Colloque C6, suppliment au no 8, Tome 39, aoljt 1978, page C6-507 STRUCTURE OF NONEQUILIBRIUM RESISTIVE STATE OF SUPERCONDUCTING STRIPS

    E-Print Network [OSTI]

    Boyer, Edmond

    depth 6E(T) into a super- conductor. f-snlimiting The voltage structure des caractQristiques courant-tension des films supraconducteurs. Abstract.- Experimental results

  19. Transition metal sulfide loaded catalyst

    DOE Patents [OSTI]

    Maroni, V.A.; Iton, L.E.; Pasterczyk, J.W.; Winterer, M.; Krause, T.R.

    1994-04-26T23:59:59.000Z

    A zeolite-based catalyst is described for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C[sub 2]+ hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

  20. New York City Transit Hybrid and CNG Transit Buses: Interim Evaluation Results

    SciTech Connect (OSTI)

    Chandler, K.; Eberts, E.; Eudy, L.

    2006-01-01T23:59:59.000Z

    This report focuses on the evaluation of compressed natural gas (CNG) and diesel hybrid electric bus propulsion systems in New York City Transit's transit buses.

  1. SunLine Transit Agency, Hydrogen Powered Transit Buses: Preliminary Evaluation Results

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2007-02-01T23:59:59.000Z

    This paper provides preliminary results from an evaluation by DOE's National Renewable Energy Laboratory of hydrogen-powered transit buses at SunLine Transit Agency.

  2. SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation...

    Broader source: Energy.gov (indexed) [DOE]

    1 August 2009 SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report Leslie Eudy, National Renewable Energy Laboratory Kevin Chandler, Battelle Link to Appendices...

  3. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation...

    Broader source: Energy.gov (indexed) [DOE]

    1 January 2009 SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report Kevin Chandler, Battelle Leslie Eudy, National Renewable Energy Laboratory Link to Appendices...

  4. ANL-78-XX-95 Energy Level Structure and Transition Probabilities

    Office of Scientific and Technical Information (OSTI)

    given by Newman and Taylor (1972). A summary of the parameters derived from LaCl, crystal studies is given in Table 1, Crosswhite (1977). As a rule of thumb for estimating atomic...

  5. Structure and magnetic behavior of transition metal based ionic liquids

    SciTech Connect (OSTI)

    Del Sesto, Rico E [Los Alamos National Laboratory (LANL); Mccleskey, T [Los Alamos National Laboratory (LANL); Burrell, Anthony K [ORNL; Baker, Gary A [ORNL; Thompson, Joe D. [Los Alamos National Laboratory (LANL); Scott, Brian L. [Los Alamos National Laboratory (LANL); Wilkes, John S [United States Air Force Academy (USAFA), Colorado; Williams, Peg [United States Air Force Academy (USAFA), Colorado

    2008-01-01T23:59:59.000Z

    A series of ionic liquids containing different paramagnetic anions have been prepared and all show paramagnetic behavior with potential applications for magnetic and electrochromic switching as well as novel magnetic transport; also, the tetraalkylphosphonium-based ionic liquids reveal anomalous magnetic behavior.

  6. ANL-78-XX-95 Energy Level Structure and Transition Probabilities

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032)8Li (59AJ76) (See theDoctoral20ALSNewstt^ \ # AN EXPERIMENT ON, . -

  7. Quantification of depth of anesthesia by nonlinear time series analysis of brain electrical activity

    E-Print Network [OSTI]

    G. Widman; T. Schreiber; B. Rehberg; A. Hoeft; C. E. Elger

    2000-07-20T23:59:59.000Z

    We investigate several quantifiers of the electroencephalogram (EEG) signal with respect to their ability to indicate depth of anesthesia. For 17 patients anesthetized with Sevoflurane, three established measures (two spectral and one based on the bispectrum), as well as a phase space based nonlinear correlation index were computed from consecutive EEG epochs. In absence of an independent way to determine anesthesia depth, the standard was derived from measured blood plasma concentrations of the anesthetic via a pharmacokinetic/pharmacodynamic model for the estimated effective brain concentration of Sevoflurane. In most patients, the highest correlation is observed for the nonlinear correlation index D*. In contrast to spectral measures, D* is found to decrease monotonically with increasing (estimated) depth of anesthesia, even when a "burst-suppression" pattern occurs in the EEG. The findings show the potential for applications of concepts derived from the theory of nonlinear dynamics, even if little can be assumed about the process under investigation.

  8. Investigation of Celotex trademark charring depths in the DT-18 shipping container

    SciTech Connect (OSTI)

    Anderson, J.C.

    1992-03-01T23:59:59.000Z

    Celotex {trademark}, the insulating material used between the outer and inner containers of the DT-18 shipping package, undergoes decomposition, combustion, or both when heated to temperatures exceeding 150{degrees}C. Several DT-18 packages that had previously undergone hypothetical thermal accident testing were opened and Celotex {trademark} charring depths ranging from {1/2} to 1 {1/2} in. were recorded. The majority of char depth data taken was between 3/4 and 1 {1/4} in. One-dimensional HEATING 7.1 models of the DT-18 package were developed. HEATING predicts charring depths of 1 to 1 1/8 in., which are in good agreement with measured values. Both experimental and analytical data indicate that charring is fairly uniform over the DT-18 package. 7 refs.

  9. Investigation of Celotex{trademark} charring depths in the DT-18 shipping container

    SciTech Connect (OSTI)

    Anderson, J.C.

    1992-03-01T23:59:59.000Z

    Celotex {trademark}, the insulating material used between the outer and inner containers of the DT-18 shipping package, undergoes decomposition, combustion, or both when heated to temperatures exceeding 150{degrees}C. Several DT-18 packages that had previously undergone hypothetical thermal accident testing were opened and Celotex {trademark} charring depths ranging from {1/2} to 1 {1/2} in. were recorded. The majority of char depth data taken was between 3/4 and 1 {1/4} in. One-dimensional HEATING 7.1 models of the DT-18 package were developed. HEATING predicts charring depths of 1 to 1 1/8 in., which are in good agreement with measured values. Both experimental and analytical data indicate that charring is fairly uniform over the DT-18 package. 7 refs.

  10. Transitivity Alternations in Sorani Kurdish

    E-Print Network [OSTI]

    Gharib, Hiba Esmail

    2011-05-31T23:59:59.000Z

    Guerssel et al. propose Lexical Conceptual Structures to account for the syntactic properties of verbs in four languages. The Lexical Conceptual Structures reference a universal set of semantic components to predict the ...

  11. Depth Profiling Of Small Molecule Ingress Into Planar and Cylindrical Materials Using NRA and PIXE

    SciTech Connect (OSTI)

    Smith, Richard W.; Massingham, Gary; Clough, Anthony S. [Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH (United Kingdom)

    2003-08-26T23:59:59.000Z

    The use of a 3He ion micro-beam technique to study the ingress/diffusion of water into a planar fibre optic grade glass and a cylindrical drug-release polymer is described. One-dimensional concentration profiles showing the depth of water ingress were produced. The depth of penetration of water into the glass was measured by fitting a gaussian function to the concentration profile. The ingress of water into the drug-release polymer was found to be Fickian and a cylindrical diffusion model used to obtain a diffusion coefficient.

  12. Soil temperature, soil moisture and thaw depth, Barrow, Alaska, Ver. 1

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sloan, V.L.; J.A. Liebig; M.S. Hahn; J.B. Curtis; J.D. Brooks; A. Rogers; C.M. Iversen; R.J. Norby

    This dataset consists of field measurements of soil properties made during 2012 and 2013 in areas A-D of Intensive Site 1 at the Next-Generation Ecosystem Experiments (NGEE) Arctic site near Barrow, Alaska. Included are i) weekly measurements of thaw depth, soil moisture, presence and depth of standing water, and soil temperature made during the 2012 and 2013 growing seasons (June - September) and ii) half-hourly measurements of soil temperature logged continuously during the period June 2012 to September 2013.

  13. Depth Profile of Uncompensated Spins in an Exchange-Bias System

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration wouldDECOMPOSITIONPortalToDepth Profile of Uncompensated Spins in anDepth

  14. IMPROVED V II log(gf) VALUES, HYPERFINE STRUCTURE CONSTANTS, AND ABUNDANCE DETERMINATIONS IN THE PHOTOSPHERES OF THE SUN AND METAL-POOR STAR HD 84937

    SciTech Connect (OSTI)

    Wood, M. P.; Lawler, J. E.; Den Hartog, E. A. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Sneden, C. [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States); Cowan, J. J., E-mail: mpwood@wisc.edu, E-mail: jelawler@wisc.edu, E-mail: eadenhar@wisc.edu, E-mail: chris@verdi.as.utexas.edu, E-mail: cowan@nhn.ou.edu [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States)

    2014-10-01T23:59:59.000Z

    New experimental absolute atomic transition probabilities are reported for 203 lines of V II. Branching fractions are measured from spectra recorded using a Fourier transform spectrometer and an echelle spectrometer. The branching fractions are normalized with radiative lifetime measurements to determine the new transition probabilities. Generally good agreement is found between this work and previously reported V II transition probabilities. Two spectrometers, independent radiometric calibration methods, and independent data analysis routines enable a reduction in systematic uncertainties, in particular those due to optical depth errors. In addition, new hyperfine structure constants are measured for selected levels by least squares fitting line profiles in the FTS spectra. The new V II data are applied to high resolution visible and UV spectra of the Sun and metal-poor star HD 84937 to determine new, more accurate V abundances. Lines covering a range of wavelength and excitation potential are used to search for non-LTE effects. Very good agreement is found between our new solar photospheric V abundance, log ?(V) = 3.95 from 15 V II lines, and the solar-system meteoritic value. In HD 84937, we derive [V/H] = –2.08 from 68 lines, leading to a value of [V/Fe] = 0.24.

  15. Benthic foraminiferal faunal changes during the Eocene/Oligocene climate transition at Ocean Drilling Program (ODP) sites 1209A and 1211A from the Shatsky Rise, central Pacific Ocean

    E-Print Network [OSTI]

    Julian, Meaghan Elizabeth

    2009-05-15T23:59:59.000Z

    indicating the core section depths, the total depth (mbsf), calculated age (Ma), and dry mass (in grams) sampled. 1211A depths mbsf age (Ma) mass (g) 9-1: 48-50 69.78 28.80 8.340 9-2: 48-50 71.28 29.40 7.180 9-3: 48-50 72.78 30.00 8.400 9-4: 48... 1209A and 1211A. At Site 1209A, our sample interval indicates that the Eocene/Oligocene transition corresponds to depths of 113.83 to 138.18 mbsf and ages of 29.66 to 36.16 Ma, whereas at Site 1211A, it corresponds to depths of 69.78 to 93.96 mbsf...

  16. Fast flux test facility, transition project plan

    SciTech Connect (OSTI)

    Guttenberg, S.

    1994-11-15T23:59:59.000Z

    The FFTF Transition Project Plan, Revision 1, provides changes and project baseline for the deactivation activities necessary to transition the FFTF to a radiologically and industrially safe shutdown condition.

  17. A Theory for the Radius of the Transiting Giant Planet HD 209458b

    E-Print Network [OSTI]

    Adam Burrows; David Sudarsky; William B. Hubbard

    2003-05-15T23:59:59.000Z

    Using a full frequency-dependent atmosphere code that can incorporate irradiation by a central primary star, we calculate self-consistent boundary conditions for the evolution of the radius of the transiting planet HD 209458b. Using a well-tested extrasolar giant planet evolutionary code, we then calculate the behavior of this planet's radius with age. The measured radius is in fact a transit radius that resides high in HD 209458b's inflated atmosphere. Using our derived atmospheric and interior structures, we find that irradiation plus the proper interpretation of the transit radius can yield a theoretical radius that is within the measured error bars. We conclude that if HD 209458b's true transit radius is at the lower end of the measured range, an extra source of core heating power is not necessary to explain the transit observations.

  18. Theoretical uncertainties in the nuclear matrix elements of neutrinoless double beta decay: The transition operator

    SciTech Connect (OSTI)

    Menéndez, Javier [Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany and ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany)

    2013-12-30T23:59:59.000Z

    We explore the theoretical uncertainties related to the transition operator of neutrinoless double-beta (0???) decay. The transition operator used in standard calculations is a product of one-body currents, that can be obtained phenomenologically as in Tomoda [1] or Šimkovic et al. [2]. However, corrections to the operator are hard to obtain in the phenomenological approach. Instead, we calculate the 0??? decay operator in the framework of chiral effective theory (EFT), which gives a systematic order-by-order expansion of the transition currents. At leading orders in chiral EFT we reproduce the standard one-body currents of Refs. [1] and [2]. Corrections appear as two-body (2b) currents predicted by chiral EFT. We compute the effects of the leading 2b currents to the nuclear matrix elements of 0??? decay for several transition candidates. The 2b current contributions are related to the quenching of Gamow-Teller transitions found in nuclear structure calculations.

  19. Transit Infrastructure Finance Through Station Location Auctions

    E-Print Network [OSTI]

    Ian Carlton

    2009-01-01T23:59:59.000Z

    Numerous route and station options Strong real estate marketreal estate market Transit friendly constituents Numerous route and station options

  20. TRB-Transit Cooperative Research Program (TCRP): Case Studies...

    Open Energy Info (EERE)

    TRB-Transit Cooperative Research Program (TCRP): Case Studies in Bus Rapid Transit Jump to: navigation, search Tool Summary LAUNCH TOOL Name: TRB-Transit Cooperative Research...

  1. Fuel Cell Transit Bus Coordination and Evaluation Plan California...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Bus Coordination and Evaluation Plan California Fuel Cell Transit Evaluation Team Fuel Cell Transit Bus Coordination and Evaluation Plan California Fuel Cell Transit Evaluation...

  2. Structural health monitoring for ship structures

    SciTech Connect (OSTI)

    Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Angel, Marian [Los Alamos National Laboratory; Bement, Matthew [Los Alamos National Laboratory; Salvino, Liming [NSWC, CADEROCK

    2009-01-01T23:59:59.000Z

    Currently the Office of Naval Research is supporting the development of structural health monitoring (SHM) technology for U.S. Navy ship structures. This application is particularly challenging because of the physical size of these structures, the widely varying and often extreme operational and environmental conditions associated with these ships missions, lack of data from known damage conditions, limited sensing that was not designed specifically for SHM, and the management of the vast amounts of data that can be collected during a mission. This paper will first define a statistical pattern recognition paradigm for SHM by describing the four steps of (1) Operational Evaluation, (2) Data Acquisition, (3) Feature Extraction, and (4) Statistical Classification of Features as they apply to ship structures. Note that inherent in the last three steps of this process are additional tasks of data cleansing, compression, normalization and fusion. The presentation will discuss ship structure SHM challenges in the context of applying various SHM approaches to sea trials data measured on an aluminum multi-hull high-speed ship, the HSV-2 Swift. To conclude, the paper will discuss several outstanding issues that need to be addressed before SHM can make the transition from a research topic to actual field applications on ship structures and suggest approaches for addressing these issues.

  3. Transition Radiation in QCD matter

    E-Print Network [OSTI]

    Magdalena Djordjevic

    2005-12-22T23:59:59.000Z

    In ultrarelativistic heavy ion collisions a finite size QCD medium is created. In this paper we compute radiative energy loss to zeroth order in opacity by taking into account finite size effects. Transition radiation occurs on the boundary between the finite size medium and the vacuum, and we show that it lowers the difference between medium and vacuum zeroth order radiative energy loss relative to the infinite size medium case. Further, in all previous computations of light parton radiation to zeroth order in opacity, there was a divergence caused by the fact that the energy loss is infinite in the vacuum and finite in the QCD medium. We show that this infinite discontinuity is naturally regulated by including the transition radiation.

  4. Sm Transition Probabilities and Abundances

    E-Print Network [OSTI]

    J. E. Lawler; E. A. Den Hartog; C. Sneden; J. J. Cowan

    2005-10-19T23:59:59.000Z

    Radiative lifetimes, accurate to +/- 5%, have been measured for 212 odd-parity levels of Sm II using laser-induced fluorescence. The lifetimes are combined with branching fractions measured using Fourier-transform spectrometry to determine transition probabilities for more than 900 lines of Sm II. This work is the largest-scale laboratory study to date of Sm II transition probabilities using modern methods. This improved data set has been used to determine a new solar photospheric Sm abundance, log epsilon = 1.00 +/- 0.03, from 26 lines. The spectra of three very metal-poor, neutron-capture-rich stars also have been analyzed, employing between 55 and 72 Sm II lines per star. The abundance ratios of Sm relative to other rare earth elements in these stars are in agreement, and are consistent with ratios expected from rapid neutron-capture nucleosynthesis (the r-process).

  5. Articulated transition duct in turbomachine

    DOE Patents [OSTI]

    Flanagan, James Scott; McMahan, Kevin Weston; LeBegue, Jeffrey Scott; Pentecost, Ronnie Ray

    2014-04-29T23:59:59.000Z

    Turbine systems are provided. A turbine system includes a transition duct comprising an inlet, an outlet, and a duct passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The duct passage includes an upstream portion and a downstream portion. The upstream portion extends from the inlet between an inlet end and an aft end. The downstream portion extends from the outlet between an outlet end and a head end. The turbine system further includes a joint coupling the aft end of the upstream portion and the head end of the downstream portion together. The joint is configured to allow movement of the upstream portion and the downstream portion relative to each other about or along at least one axis.

  6. Turbulent Transition in an Electromagnetically Levitated Droplet

    E-Print Network [OSTI]

    Mountziaris, T. J.

    Turbulent Transition in an Electromagnetically Levitated Droplet Christina R. Rizer, Robert W a marked transition from laminar to turbulent flow, which can be observed by following the movement, will oscillate and break apart, marking the transition to turbulence. Using videos taken of these metal samples

  7. Contact Transition Control: An Experimental Study

    E-Print Network [OSTI]

    Stanford University

    Contact Transition Control: An Experimental Study James M. Hyde and Mark R. Cutkosky Center Successful control of contact transitions is an important capability of dextrous robotic manipulators. In this paper we examine several methods for controlling the transition from free motion to constrained motion

  8. Combined UHV/high-pressure catalysis setup for depth-resolved near-surface spectroscopic characterization and catalytic testing of model catalysts

    SciTech Connect (OSTI)

    Mayr, Lukas; Klötzer, Bernhard; Penner, Simon [Institute of Physical Chemistry, University of Innsbruck, Innrain 52a, 6020 Innsbruck (Austria)] [Institute of Physical Chemistry, University of Innsbruck, Innrain 52a, 6020 Innsbruck (Austria); Rameshan, Raffael [Institute of Physical Chemistry, University of Innsbruck, Innrain 52a, 6020 Innsbruck (Austria) [Institute of Physical Chemistry, University of Innsbruck, Innrain 52a, 6020 Innsbruck (Austria); Department of Inorganic Chemistry, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin (Germany); Rameshan, Christoph [Institute of Physical Chemistry, University of Innsbruck, Innrain 52a, 6020 Innsbruck (Austria) [Institute of Physical Chemistry, University of Innsbruck, Innrain 52a, 6020 Innsbruck (Austria); Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9/BC/01, 1060 Vienna (Austria)

    2014-05-15T23:59:59.000Z

    An ultra-high vacuum (UHV) setup for “real” and “inverse” model catalyst preparation, depth-resolved near-surface spectroscopic characterization, and quantification of catalytic activity and selectivity under technologically relevant conditions is described. Due to the all-quartz reactor attached directly to the UHV-chamber, transfer of the catalyst for in situ testing without intermediate contact to the ambient is possible. The design of the UHV-compatible re-circulating batch reactor setup allows the study of reaction kinetics under close to technically relevant catalytic conditions up to 1273 K without contact to metallic surfaces except those of the catalyst itself. With the attached differentially pumped exchangeable evaporators and the quartz-microbalance thickness monitoring equipment, a reproducible, versatile, and standardised sample preparation is possible. For three-dimensional near-surface sample characterization, the system is equipped with a hemispherical analyser for X-ray photoelectron spectroscopy (XPS), electron-beam or X-ray-excited Auger-electron spectroscopy, and low-energy ion scattering measurements. Due the dedicated geometry of the X-ray gun (54.7°, “magic angle”) and the rotatable sample holder, depth analysis by angle-resolved XPS measurements can be performed. Thus, by the combination of characterisation methods with different information depths, a detailed three-dimensional picture of the electronic and geometric structure of the model catalyst can be obtained. To demonstrate the capability of the described system, comparative results for depth-resolved sample characterization and catalytic testing in methanol steam reforming on PdGa and PdZn near-surface intermetallic phases are shown.

  9. Highly transitive imprimitivities Marston Conder

    E-Print Network [OSTI]

    Conder, Marston

    . Thus dimP n is the number of orbits of G on X n . Before proceeding further, we should point out for the action of the symmetric group SX on X n is a lower bound for dimP n , and to say an action is k-transitive is just to say that dimP k is equal to that lower bound. For jXj > n this number of orbits is equal

  10. Transition physics and scaling overview

    SciTech Connect (OSTI)

    Carlstrom, T.N.

    1995-12-01T23:59:59.000Z

    This paper presents an overview of recent experimental progress towards understanding H-mode transition physics and scaling. Terminology and techniques for studying H-mode are reviewed and discussed. The model of shear E x B flow stabilization of edge fluctuations at the L-H transition is gaining wide acceptance and is further supported by observations of edge rotation on a number of new devices. Observations of poloidal asymmetries of edge fluctuations and dephasing of density and potential fluctuations after the transition pose interesting challenges for understanding H-mode physics. Dedicated scans to determine the scaling of the power threshold have now been performed on many machines. A dear B{sub t} dependence is universally observed but dependence on the line averaged density is complicated. Other dependencies are also reported. Studies of the effect of neutrals and error fields on the power threshold are under investigation. The ITER threshold database has matured and offers guidance to the power threshold scaling issues relevant to next-step devices.

  11. Photothermoacoustic imaging of biological tissues: maximum depth characterization comparison of time and

    E-Print Network [OSTI]

    Mandelis, Andreas

    Photothermoacoustic imaging of biological tissues: maximum depth characterization comparison for Advanced Diffusion-Wave Technologies Department of Mechanical and Industrial Engineering 5 King's College induced in light-absorbing materials can be observed either as a transient signal in time domain

  12. Integrating Kinect Depth Data with a Stochastic Object Classification Framework for Forestry Robots

    E-Print Network [OSTI]

    Hellström, Thomas

    Integrating Kinect Depth Data with a Stochastic Object Classification Framework for Forestry Robots camera for a stochastic classification system for forestry robots. The images are classified as bush- ject classification system that uses only RGB camera. The system is aimed for a forestry robot

  13. Secure Computation of Constant-Depth Circuits with Applications to Database Search Problems

    E-Print Network [OSTI]

    Shpilka, Amir

    Secure Computation of Constant-Depth Circuits with Applications to Database Search Problems Omer. Motivated by database search problems such as partial match or nearest neighbor, we present secure between k poly log(s) parties who all know C, we obtain a secure protocol for evaluating C(x) using O

  14. Secure Computation of Constant-Depth Circuits with Applications to Database Search Problems ?

    E-Print Network [OSTI]

    Ishai, Yuval

    Secure Computation of Constant-Depth Circuits with Applications to Database Search Problems ? Omer. Motivated by database search problems such as partial match or nearest neighbor, we present secure distributed between k #21; poly log(s) parties who all know C, we obtain a secure protocol for evaluating C

  15. An in-depth Analysis of Space Heating Energy Use in Office Buildings

    E-Print Network [OSTI]

    LBNL-5732E An in-depth Analysis of Space Heating Energy Use in Office Buildings Author(s), Hung Energy, Building Technologies Program, of the U.S. Department of Energy under Contract No. DE-AC02-05CH than 7 trillion Joules of site energy annually [USDOE]. Analyzing building space heating performance

  16. Probabilistic models and reliability analysis of scour depth around bridge piers

    E-Print Network [OSTI]

    Bolduc, Laura Christine

    2009-06-02T23:59:59.000Z

    parameters suggest that the maximum sour depth predicted by the deterministic HEC-18 Sand and HEC-18 Clay models tend to be conservative. Evidence is also found that the applicability of the HEC-18 Clay method is not limited to clay but can also be used...

  17. Energy-Based 6-DOF Penetration Depth Computation for Penalty-Based Haptic Rendering Algorithms

    E-Print Network [OSTI]

    Zefran, Milo?

    Energy-Based 6-DOF Penetration Depth Computation for Penalty-Based Haptic Rendering Algorithms Maxim Kolesnikov and Milos Zefran Abstract-- Existing penalty-based haptic rendering ap- proaches of rigid-body motions SE(3). We propose a penalty-based six-degrees-of-freedom (6-DOF) haptic rendering

  18. Oil and Gas CDT Predicting fault permeability at depth: incorporating natural

    E-Print Network [OSTI]

    Henderson, Gideon

    Oil and Gas CDT Predicting fault permeability at depth: incorporating natural permeability controls on fluid flow in oil and gas reservoirs. Fault zones are composed of many deformation elements will receive 20 weeks bespoke, residential training of broad relevance to the oil and gas industry: 10 weeks

  19. Unravelling the influence of water depth and wave energy on the facies diversity of shelf carbonates

    E-Print Network [OSTI]

    Purkis, Sam

    Unravelling the influence of water depth and wave energy on the facies diversity of shelf their production is tied to light and wave energy, carbonate sediments are most effectively produced in shallow energy regime to be reliable indicators of facies type when considered in isolation. Consid- ered

  20. Submission (November 1, 2001) to 'Journal of Systems and Software' A Controlled Experiment on Inheritance Depth

    E-Print Network [OSTI]

    Prechelt, Lutz

    effort that is much more powerful than a model relying on inheritance depth. Keywords: controlled of the key elements that makes object-oriented programming powerful[Meyer, 1997]. Many design problems canSubmission (November 1, 2001) to 'Journal of Systems and Software' A Controlled Experiment

  1. Submission (November 1, 2001) to 'Journal of Systems and Software' A Controlled Experiment on Inheritance Depth

    E-Print Network [OSTI]

    Prechelt, Lutz

    effort that is much more powerful than a model relying on inheritance depth. Keywords: controlledSubmission (November 1, 2001) to 'Journal of Systems and Software' A Controlled Experiment was significantly easier to maintain than the 0­level program. We describe the design and setup of our experiment

  2. The depth of the tropical Pacific Ocean's warm surface layer shrank during the last three

    E-Print Network [OSTI]

    Yanik, Mehmet Fatih

    The depth of the tropical Pacific Ocean's warm surface layer shrank during the last three decades Pacific Ocean, off an island in Palau. They analysed the ratio of nitrogen and carbon isotopes.1029/2010GL044867 (2010) OceanOgraphy Cold water rising in the Pacific DrUg DeVeLOpMenT Worm surgery on a chip

  3. Anytime AND/OR Depth-first Search for Combinatorial Optimization

    E-Print Network [OSTI]

    Dechter, Rina

    ] [ ] Decomposition Cache table for F (independent of A) Time and Space: O( n·k w ) Prune based on current best with current child subproblems. 1. Move breadth-first to next open subproblem P . 2. Process P depth-first, until either: P is solved optimally, P decomposes into child subproblems, a predefined threshold

  4. Distinct compositional thin layers at mid-mantle depths beneath northeast China revealed by the USArray

    E-Print Network [OSTI]

    Niu, Fenglin

    Natural Gas Institute, China University of Petroleum, Beijing, China b Department of Earth Science, RiceDistinct compositional thin layers at mid-mantle depths beneath northeast China revealed crust northeast China USArray a b s t r a c t We observe a clear seismic arrival at $35­45 s after

  5. Distinct compositional thin layers at mid-mantle depths beneath northeast China revealed by the USArray

    E-Print Network [OSTI]

    Niu, Fenglin

    Natural Gas Institute, China University of Petroleum, Beijing, China b Department of Earth Science, RiceDistinct compositional thin layers at mid-mantle depths beneath northeast China revealed February 2013 Keywords: S to P converted wave mid-mantle reflectors subducted oceanic crust northeast China

  6. {sup 152}Eu depths profiles granite and concrete cores exposed to the Hiroshima atomic bomb

    SciTech Connect (OSTI)

    Shizuma, Kiyoshi; Iwatani, Kazuo [Hiroshima Univ. (Japan); Oka, Takamitsu [Kure Univ. (Japan)] [and others

    1997-06-01T23:59:59.000Z

    Two granite and two concrete core samples were obtained within 500 m from the hypocenter of the Hiroshima atomic bomb, and the depth profile of {sup 152}Eu was measured to evaluate the incident neutron spectrum. The granite cores were obtained from a pillar of the Motoyasu Bridge located 101 m from the hypocenter and from a granite rock in the Shirakami Shrine (379 m); the concrete cores were obtained from a gate in the Gokoku Shrine (398 m) and from top of the Hiroshima bank (250 m). The profiles of the specific activities of the cores were measured to a depth of 40 cm from the surface using low background germanium (Ge) spectrometers. According to the measured depth profiles, relaxation lengths of incident neutrons were derived as 13.6 cm for Motoyasu Bridge pillar (granite), 12.2 cm for Shirakami Shrine core (granite), and 9.6 cm for concrete cores of Gokoku Shrine and Hiroshima Bank. In addition, a comparison of the granite cores in Hiroshima showed good agreement with Nagasaki data. Present results indicates that the depth profile of {sup 152}Eu reflects incident neutrons not so high but in the epithermal region. 19 refs., 7 figs., 8 tabs.

  7. Refining k-means by Bootstrap and Data Depth Aurora Torrente and Juan Romo

    E-Print Network [OSTI]

    Romo, Juan

    Refining k-means by Bootstrap and Data Depth Aurora Torrente and Juan Romo Departamento de Estad two simple, computationally fast methods that allow the refinement of the initial points of k-means to cluster a given data set. They are based on alternating k-means and the search of the deepest (most

  8. Long prereproductive selection and divergence by depth in a Caribbean candelabrum coral

    E-Print Network [OSTI]

    Hellberg, Michael E.

    Long prereproductive selection and divergence by depth in a Caribbean candelabrum coral Carlos of the candelabrum coral Eunicea flexuosa across the Caribbean. Eunicea is endemic to the Caribbean and all sister: How can new marine species emerge without obvious geographic isolation? Caribbean coral reefs

  9. Laser infrared photothermal radiometric depth profilometry of steels and its potential in rail track evaluation

    E-Print Network [OSTI]

    Mandelis, Andreas

    -scattering or in the transmission mode using a variety of sensor probes. In this work we used the infrared (IR) photothermal radioLaser infrared photothermal radiometric depth profilometry of steels and its potential in rail track evaluation A. Mandelis*, M. Munidasa, L. Nicolaides Photothermal and Optoelectronic Diagnostics

  10. The role of nutricline depth in regulating the ocean carbon cycle

    E-Print Network [OSTI]

    The role of nutricline depth in regulating the ocean carbon cycle Pedro Cermen~ oa , Stephanie, 77 Massachusetts Avenue, Massachusetts Institute of Technology, Cambridge, MA 02139-4307; c play key roles in the regulation of atmospheric pCO2 and the maintenance of upper trophic levels (1

  11. Possible overestimation of shallow-depth calcium carbonate dissolution in the ocean

    E-Print Network [OSTI]

    Follows, Mick

    Possible overestimation of shallow-depth calcium carbonate dissolution in the ocean K. Friis,1,2 R calcium carbonate (TA*) above the saturation horizon cannot be unambiguously interpreted in terms of local and biogeochemistry with explicit representation of the formation and dissolution of calcium carbonate. In particular

  12. IEA BESTEST Multi-Zone Non-Airflow In-Depth Diagnostic Cases: Preprint

    SciTech Connect (OSTI)

    Neymark, J.; Judkoff, R.; Alexander, D.; Felsmann, C.; Strachan, P.; Wijsman, A.

    2011-11-01T23:59:59.000Z

    This paper documents a set of in-depth diagnostic test cases for multi-zone heat transfer models that do not include the heat and mass transfer effects of airflow between zones. The multi-zone non-airflow test cases represent an extension to IEA BESTEST (Judkoff and Neymark 1995a).

  13. Numerical Simulation of Impact Rollers for Estimating the Influence Depth of Soil Compaction

    E-Print Network [OSTI]

    Kim, Kukjoo

    2011-10-21T23:59:59.000Z

    will estimate more precisely the depth of influence for impact rollers. To do so, the general purpose finite element computer program LS-DYNA is used for numerical predictions. The finite element study is carried out with three-dimensional models. A simplified...

  14. CHARACTERISATION OF AGED HDPE PIPES FROM DRINKING WATER DISTRIBUTION: INVESTIGATION OF CRACK DEPTH BY NOL RING

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    BY NOL RING TESTS UNDER CREEP LOADING C. Devilliers 1), 2), 3) , L. Laiarinandrasana 1) , B. Fayolle 2. KEYWORDS HDPE pipes, Nol Ring creep test, ageing effects, fracture mechanism, crack depth ratio, aged layer loading than a monotonic tensile loading. It is to be noticed that the Nol Ring test subjected to a creep

  15. Maximum Neutral Buoyancy Depth of Juvenile Chinook Salmon: Implications for Survival during Hydroturbine Passage

    SciTech Connect (OSTI)

    Pflugrath, Brett D.; Brown, Richard S.; Carlson, Thomas J.

    2012-03-01T23:59:59.000Z

    This study investigated the maximum depth at which juvenile Chinook salmon Oncorhynchus tshawytscha can acclimate by attaining neutral buoyancy. Depth of neutral buoyancy is dependent upon the volume of gas within the swim bladder, which greatly influences the occurrence of injuries to fish passing through hydroturbines. We used two methods to obtain maximum swim bladder volumes that were transformed into depth estimations - the increased excess mass test (IEMT) and the swim bladder rupture test (SBRT). In the IEMT, weights were surgically added to the fishes exterior, requiring the fish to increase swim bladder volume in order to remain neutrally buoyant. SBRT entailed removing and artificially increasing swim bladder volume through decompression. From these tests, we estimate the maximum acclimation depth for juvenile Chinook salmon is a median of 6.7m (range = 4.6-11.6 m). These findings have important implications to survival estimates, studies using tags, hydropower operations, and survival of juvenile salmon that pass through large Kaplan turbines typical of those found within the Columbia and Snake River hydropower system.

  16. A New Theory for the Atmospheric Energy Spectrum: Depth-Limited Temperature Anomalies at the Tropopause

    E-Print Network [OSTI]

    Smith, K. Shafer

    A New Theory for the Atmospheric Energy Spectrum: Depth-Limited Temperature Anomalies Sciences, New York University, 251 Mercer Street, New York, NY 10012 Communicated by Andrew J. Majda, June- bations generated at the planetary scale excite a direct cas- cade of energy with a slope of -3 at large

  17. Probing the Depths of CSP-M: A new fdr-compliant Validation Tool

    E-Print Network [OSTI]

    Southampton, University of

    Probing the Depths of CSP-M: A new fdr-compliant Validation Tool Michael Leuschel and Marc Fontaine,fontaine}@cs.uni-duesseldorf.de Abstract. We present a new animation and model checking tool for CSP. The tool covers the CSP-M language in the source code, has an LTL model checker and can be used for combined CSP B specifications. During

  18. London penetration depth and coherence length of SU(3) vacuum flux tubes

    E-Print Network [OSTI]

    Paolo Cea; Leonardo Cosmai; Francesca Cuteri; Alessandro Papa

    2014-10-16T23:59:59.000Z

    The transverse profile of the chromoelectric field generated by a quark-antiquark pair in the SU(3) vacuum is analysed within the dual superconductor scenario, then the London penetration depth and coherence length are extracted. The color field is determined on the lattice through a connected correlator of two Polyakov loops measured on smeared configurations.

  19. The effect of ocean mixed layer depth on climate in slab ocean aquaplanet experiments

    E-Print Network [OSTI]

    Battisti, David

    a severely reduced (&50 %) meridi- onal energy transport relative to the deep ocean runs. As a resultThe effect of ocean mixed layer depth on climate in slab ocean aquaplanet experiments Aaron Donohoe online: 28 June 2013 Ã? Springer-Verlag Berlin Heidelberg 2013 Abstract The effect of ocean mixed layer

  20. Solid precipitation on a tropical glacier in Bolivia measured with an ultrasonic depth gauge

    E-Print Network [OSTI]

    Berthier, Etienne

    Solid precipitation on a tropical glacier in Bolivia measured with an ultrasonic depth gauge Jean´veloppement, La Paz, Bolivia Received 24 April 2002; revised 6 June 2002; accepted 6 June 2002; published 10 the equilibrium line of the Zongo glacier (2.4 km2 ), Bolivia (16°S). Study of the influence of wind, air

  1. Transition pathways in complex systems: Reaction coordinates, isocommittor surfaces, and transition tubes

    E-Print Network [OSTI]

    Van Den Eijnden, Eric

    Transition pathways in complex systems: Reaction coordinates, isocommittor surfaces, and transition form 20 July 2005 Available online 18 August 2005 Abstract The mechanism of transition (reaction. These surfaces can be used to identify effective transition tubes inside which the reactive trajectories involved

  2. Pressure-Induced Electronic Phase Transitions Transition Metal Oxides and Rare Earth Metals

    E-Print Network [OSTI]

    Islam, M. Saif

    Pressure-Induced Electronic Phase Transitions in Transition Metal Oxides and Rare Earth Metals Metal Oxides and Rare Earth Metals by Brian Ross Maddox Electron correlation can affect profound changes transition in a transition metal monoxide. iv #12;The lanthanides (the 4f metals also known as rare-earths

  3. DETECTION OF POTENTIAL TRANSIT SIGNALS IN THE FIRST 12 QUARTERS OF KEPLER MISSION DATA

    SciTech Connect (OSTI)

    Tenenbaum, Peter; Jenkins, Jon M.; Seader, Shawn; Burke, Christopher J.; Christiansen, Jessie L.; Rowe, Jason F.; Caldwell, Douglas A.; Clarke, Bruce D.; Li, Jie; Quintana, Elisa V.; Smith, Jeffrey C.; Thompson, Susan E.; Twicken, Joseph D. [SETI Institute/NASA Ames Research Center, Moffett Field, CA 94305 (United States)] [SETI Institute/NASA Ames Research Center, Moffett Field, CA 94305 (United States); Borucki, William J.; Batalha, Natalie M.; Cote, Miles T.; Haas, Michael R.; Hunter, Roger C.; Sanderfer, Dwight T. [NASA Ames Research Center, Moffett Field, CA 94305 (United States)] [NASA Ames Research Center, Moffett Field, CA 94305 (United States); Girouard, Forrest R., E-mail: peter.tenenbaum@nasa.gov [Orbital Sciences Corporation/NASA Ames Research Center, Moffett Field, CA 94305 (United States); and others

    2013-05-01T23:59:59.000Z

    We present the results of a search for potential transit signals in the first three years of photometry data acquired by the Kepler mission. The targets of the search include 112,321 targets that were observed over the full interval and an additional 79,992 targets that were observed for a subset of the full interval. From this set of targets we find a total of 11,087 targets that contain at least one signal that meets the Kepler detection criteria: periodicity of the signal, an acceptable signal-to-noise ratio, and three tests that reject false positives. Each target containing at least one detected signal is then searched repeatedly for additional signals, which represent multi-planet systems of transiting planets. When targets with multiple detections are considered, a total of 18,406 potential transiting planet signals are found in the Kepler mission data set. The detected signals are dominated by events with relatively low signal-to-noise ratios and by events with relatively short periods. The distribution of estimated transit depths appears to peak in the range between 20 and 30 parts per million, with a few detections down to fewer than 10 parts per million. The detections exhibit signal-to-noise ratios from 7.1{sigma}, which is the lower cutoff for detections, to over 10,000{sigma}, and periods ranging from 0.5 days, which is the shortest period searched, to 525 days, which is the upper limit of achievable periods given the length of the data set and the requirement that all detections include at least three transits. The detected signals are compared to a set of known transit events in the Kepler field of view, many of which were identified by alternative methods; the comparison shows that the current search recovery rate for targets with known transit events is 98.3%.

  4. Structuring Structural Operational

    E-Print Network [OSTI]

    Mousavi, Mohammad

    aan de Technische Universiteit Eindhoven, op gezag van de Rector Magnificus, prof.dr.ir. C.J. van.A. Reniers CIP­DATA LIBRARY TECHNISCHE UNIVERSITEIT EINDHOVEN Mousavi, MohammadReza Structuring Structural Operational Semantics / MohammadReza Mousavi. ­ Eindhoven : Technische Universiteit Eindhoven, 2005

  5. Structuring Structural Operational

    E-Print Network [OSTI]

    Reniers, Michel

    aan de Technische Universiteit Eindhoven, op gezag van de Rector Magnificus, prof.dr.ir. C.J. van.A. Reniers CIP-DATA LIBRARY TECHNISCHE UNIVERSITEIT EINDHOVEN Mousavi, MohammadReza Structuring Structural Operational Semantics / MohammadReza Mousavi. - Eindhoven : Technische Universiteit Eindhoven, 2005

  6. Unveiling temporal correlations characteristic to phase transition in the intensity of a fibre laser radiation

    E-Print Network [OSTI]

    Andres Aragoneses; Laura Carpi; Nikita Tarasov; Dmitry V. Churkin; M. C. Torrent; Cristina Masoller; Sergei K. Turitsyn

    2015-06-09T23:59:59.000Z

    We use advanced statistical tools of time-series analysis to characterize the dynamical complexity of the transition to optical wave turbulence in a fibre laser. Ordinal analysis and the horizontal visibility graph applied to the experimentally measured laser output intensity reveal the presence of temporal correlations during the transition from the laminar to the turbulent lasing regimes. Both methods unveil coherent structures with well defined time-scales and strong correlations both, in the timing of the laser pulses and in their peak intensities. Our approach is generic and may be used in other complex systems that undergo similar transitions involving the generation of extreme fluctuations.

  7. Dual order parameters and the deconfinement transition

    E-Print Network [OSTI]

    Christian S. Fischer; Jens A. Mueller

    2009-10-29T23:59:59.000Z

    We investigate the chiral and the deconfinement transition within the framework of Dyson-Schwinger equations using quenched lattice data for the temperature dependent gluon propagator as input. We extract corresponding order parameters from the Landau gauge quark propagator with U(1)-valued boundary conditions. We study the chiral transition using the conventional quark condensate, whereas for the deconfinement transition we determine the dual condensate ('dressed Polyakov loop'). In addition we consider an alternative order parameter for deconfinement, the dual scalar quark dressing function. As a result we find almost the same transition temperatures for the chiral and deconfinement transitions.

  8. TRANSITION STATE FOR THE GAS-PHASE REACTION OF URANIUM HEXAFLUORIDE WITH WATER

    SciTech Connect (OSTI)

    Garrison, S; James Becnel, J

    2008-03-18T23:59:59.000Z

    Density Functional Theory and small-core, relativistic pseudopotentials were used to look for symmetric and asymmetric transitions states of the gas-phase hydrolysis reaction of uranium hexafluoride, UF{sub 6}, with water. At the B3LYP/6-31G(d,p)/SDD level, an asymmetric transition state leading to the formation of a uranium hydroxyl fluoride, U(OH)F{sub 5}, and hydrogen fluoride was found with an energy barrier of +77.3 kJ/mol and an enthalpy of reaction of +63.0 kJ/mol (both including zero-point energy corrections). Addition of diffuse functions to all atoms except uranium led to only minor changes in the structure and relative energies of the reacting complex and transition state. However, a significant change in the product complex structure was found, significantly reducing the enthalpy of reaction to +31.9 kJ/mol. Similar structures and values were found for PBE0 and MP2 calculations with this larger basis set, supporting the B3LYP results. No symmetric transition state leading to the direct formation of uranium oxide tetrafluoride, UOF{sub 4}, was found, indicating that the reaction under ambient conditions likely includes several more steps than the mechanisms commonly mentioned. The transition state presented here appears to be the first published transition state for the important gas-phase reaction of UF{sub 6} with water.

  9. Application of elastic-plastic fracture mechanics to marine structures 

    E-Print Network [OSTI]

    Pathi, Amarkumar

    1991-01-01T23:59:59.000Z

    , be able to support the loads that are applied during its operating lifetime. The structural integrity of components can be assured by knowledge of the material used in their construction. The fracture behavior of a given structure or material depends... or fatigue cracks. Ship structures operate in or near the ductile-brittle transition region, where the failure mechanism is unstable cleavage. Consequently materials are characterized by a transition temperature region above which they may be safely used...

  10. Constraining Orbital Parameters Through Planetary Transit Monitoring

    E-Print Network [OSTI]

    Stephen R. Kane; Kaspar von Braun

    2008-08-13T23:59:59.000Z

    The orbital parameters of extra-solar planets have a significant impact on the probability that the planet will transit the host star. This was recently demonstrated by the transit detection of HD 17156b whose favourable eccentricity and argument of periastron dramatically increased its transit likelihood. We present a study which provides a quantitative analysis of how these two orbital parameters affect the geometric transit probability as a function of period. Further, we apply these results to known radial velocity planets and show that there are unexpectedly high transit probabilities for planets at relatively long periods. For a photometric monitoring campaign which aims to determine if the planet indeed transits, we calculate the expected transiting planet yield and the significance of a potential null result, as well as the subsequent constraints that may be applied to orbital parameters.

  11. Approximating Metal-Insulator Transitions

    E-Print Network [OSTI]

    C. Danieli; K. Rayanov; B. Pavlov; G. Martin; S. Flach

    2014-05-06T23:59:59.000Z

    We consider quantum wave propagation in one-dimensional quasiperiodic lattices. We propose an iterative construction of quasiperiodic potentials from sequences of potentials with increasing spatial period. At each finite iteration step the eigenstates reflect the properties of the limiting quasiperiodic potential properties up to a controlled maximum system size. We then observe approximate metal-insulator transitions (MIT) at the finite iteration steps. We also report evidence on mobility edges which are at variance to the celebrated Aubry-Andre model. The dynamics near the MIT shows a critical slowing down of the ballistic group velocity in the metallic phase similar to the divergence of the localization length in the insulating phase.

  12. Shim for sealing transition pieces

    DOE Patents [OSTI]

    Lacy, Benjamin Paul (Greer, SC); Demiroglu, Mehmet (Troy, NY); Sarawate, Neelesh Nandkumar (Niskayuna, NY)

    2012-07-24T23:59:59.000Z

    According to one aspect of the invention, a shim for sealing two adjacent turbine transition pieces is disclosed. The shim includes a circumferential member that includes a first lateral flange and a second lateral flange. Further, the first and second lateral flanges each comprise a tab configured to mate to a first surface plane and the first and second lateral flanges are configured to mate to a second surface plane, wherein the first and second surface planes are substantially parallel. In addition, the shim includes a first flange extending substantially perpendicular from the circumferential member.

  13. Phase Transition in Tensor Models

    E-Print Network [OSTI]

    Delepouve, Thibault

    2015-01-01T23:59:59.000Z

    Generalizing matrix models, tensor models generate dynamical triangulations in any dimension and support a $1/N$ expansion. Using the intermediate field representation we explicitly rewrite a quartic tensor model as a field theory for a fluctuation field around a vacuum state corresponding to the resummation of the entire leading order in $1/N$ (a resummation of the melonic family). We then prove that the critical regime in which the continuum limit in the sense of dynamical triangulations is reached is precisely a phase transition in the field theory sense for the fluctuation field.

  14. Weak-strong clustering transition in renewing compressible flows

    E-Print Network [OSTI]

    Ajinkya Dhanagare; Stefano Musacchio; Dario Vincenzi

    2014-11-01T23:59:59.000Z

    We investigate the statistical properties of Lagrangian tracers transported by a time-correlated compressible renewing flow. We show that the preferential sampling of the phase space performed by tracers yields significant differences between the Lagrangian statistics and its Eulerian counterpart. In particular, the effective compressibility experienced by tracers has a non-trivial dependence on the time correlation of the flow. We examine the consequence of this phenomenon on the clustering of tracers, focusing on the transition from the weak- to the strong-clustering regime. We find that the critical compressibility at which the transition occurs is minimum when the time correlation of the flow is of the order of the typical eddy turnover time. Further, we demonstrate that the clustering properties in time-correlated compressible flows are non-universal and are strongly influenced by the spatio-temporal structure of the velocity field.

  15. Energy-landscape network approach to the glass transition

    E-Print Network [OSTI]

    Shai Carmi; Shlomo Havlin; Chaoming Song; Kun Wang; Hernan A. Makse

    2009-03-14T23:59:59.000Z

    We study the energy-landscape network of Lennard-Jones clusters as a model of a glass forming system. We find the stable basins and the first order saddles connecting them, and identify them with the network nodes and links, respectively. We analyze the network properties and model the system's evolution. Using the model, we explore the system's response to varying cooling rates, and reproduce many of the glass transition properties. We also find that the static network structure gives rise to a critical temperature where a percolation transition breaks down the space of configurations into disconnected components. Finally, we discuss the possibility of studying the system mathematically with a trap-model generalized to networks.

  16. Ductile-to-brittle transition in spallation of metallic glasses

    SciTech Connect (OSTI)

    Huang, X. [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang, Sichuan 621999 (China); Ling, Z. [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Dai, L. H., E-mail: lhdai@lnm.imech.ac.cn [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 10081 (China)

    2014-10-14T23:59:59.000Z

    In this paper, the spallation behavior of a binary metallic glass Cu{sub 50}Zr{sub 50} is investigated with molecular dynamics simulations. With increasing the impact velocity, micro-voids induced by tensile pulses become smaller and more concentrated. The phenomenon suggests a ductile-to-brittle transition during the spallation process. Further investigation indicates that the transition is controlled by the interaction between void nucleation and growth, which can be regarded as a competition between tension transformation zones (TTZs) and shear transformation zones (STZs) at atomic scale. As impact velocities become higher, the stress amplitude and temperature rise in the spall region increase and micro-structures of the material become more unstable. Therefore, TTZs are prone to activation in metallic glasses, leading to a brittle behavior during the spallation process.

  17. Weak-strong clustering transition in renewing compressible flows

    E-Print Network [OSTI]

    Dhanagare, Ajinkya; Vincenzi, Dario

    2014-01-01T23:59:59.000Z

    We investigate the statistical properties of Lagrangian tracers transported by a time-correlated compressible renewing flow. We show that the preferential sampling of the phase space performed by tracers yields significant differences between the Lagrangian statistics and its Eulerian counterpart. In particular, the effective compressibility experienced by tracers has a non-trivial dependence on the time correlation of the flow. We examine the consequence of this phenomenon on the clustering of tracers, focusing on the transition from the weak- to the strong-clustering regime. We find that the critical compressibility at which the transition occurs is minimum when the time correlation of the flow is of the order of the typical eddy turnover time. Further, we demonstrate that the clustering properties in time-correlated compressible flows are non-universal and are strongly influenced by the spatio-temporal structure of the velocity field.

  18. ASSESSMENT OF SEISMIC ANALYSIS METHODOLOGIES FOR DEEPLY EMBEDDED NPP STRUCTURES.

    SciTech Connect (OSTI)

    XU, J.; MILLER, C.; COSTANTINO, C.; HOFMAYER, C. (BNL); GRAVES, H. (US NRC).

    2005-07-01T23:59:59.000Z

    Several of the new generation nuclear power plant designs have structural configurations which are proposed to be deeply embedded. Since current seismic analysis methodologies have been applied to shallow embedded structures (e.g., ASCE 4 suggest that simple formulations may be used to model embedment effect when the depth of embedment is less than 30% of its foundation radius), the US Nuclear Regulatory Commission is sponsoring a program at the Brookhaven National Laboratory with the objective of investigating the extent to which procedures acceptable for shallow embedment depths are adequate for larger embedment depths. This paper presents the results of a study comparing the response spectra obtained from two of the more popular analysis methods for structural configurations varying from shallow embedment to complete embedment. A typical safety related structure embedded in a soil profile representative of a typical nuclear power plant site was utilized in the study and the depths of burial (DOB) considered range from 25-100% the height of the structure. Included in the paper are: (1) the description of a simplified analysis and a detailed approach for the SSI analyses of a structure with various DOB, (2) the comparison of the analysis results for the different DOBs between the two methods, and (3) the performance assessment of the analysis methodologies for SSI analyses of deeply embedded structures. The resulting assessment from this study has indicated that simplified methods may be capable of capturing the seismic response for much deeper embedded structures than would be normally allowed by the standard practice.

  19. Surface hardening of titanium alloys with melting depth controlled by heat sink

    DOE Patents [OSTI]

    Oden, Laurance L. (Albany, OR); Turner, Paul C. (Albany, OR)

    1995-01-01T23:59:59.000Z

    A process for forming a hard surface coating on titanium alloys includes providing a piece of material containing titanium having at least a portion of one surface to be hardened. The piece having a portion of a surface to be hardened is contacted on the backside by a suitable heat sink such that the melting depth of said surface to be hardened may be controlled. A hardening material is then deposited as a slurry. Alternate methods of deposition include flame, arc, or plasma spraying, electrodeposition, vapor deposition, or any other deposition method known by those skilled in the art. The surface to be hardened is then selectively melted to the desired depth, dependent on the desired coating thickness, such that a molten pool is formed of the piece surface and the deposited hardening material. Upon cooling a hardened surface is formed.

  20. Transitional nuclei near shell closures

    SciTech Connect (OSTI)

    Mukherjee, G. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064 (India); Pai, H. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064, India and Present Address: Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstrasse 9, 64289 Darmstadt (Germany)

    2014-08-14T23:59:59.000Z

    High spin states in Bismuth and Thallium nuclei near the Z = 82 shell closure and Cesium nuclei near the N = 82 shell closure in A = 190 and A = 130 regions, respectively, have been experimentally investigated using heavy-ion fusion evaporation reaction and by detecting the gamma rays using the Indian National Gamma Array (INGA). Interesting shape properties in these transitional nuclei have been observed. The results were compared with the neighboring nuclei in these two regions. The total Routhian surface (TRS) calculations have been performed for a better understanding of the observed properties. In mass region A = 190, a change in shape from spherical to deformed has been observd around neutron number N = 112 for the Bi (Z = 83) isotopes with proton number above the magic gap Z = 82, whereas, the shape of Tl (Z = 81) isotopes with proton number below the magic gap Z = 82 remains stable as a function of neutron number. An important transition from aplanar to planar configuration of angular momentum vectors leading to the occurance of nuclar chirality and magnetic rotation, respectively, has been proposed for the unique parity ?h{sub 11/2}??h{sub 11/2} configuration in Cs isotopes in the mass region A ? 130 around neutron number N = 79. These results are in commensurate with the TRS calculations.

  1. Gd Transition Probabilities and Abundances

    E-Print Network [OSTI]

    E. A. Den Hartog; J. E. Lawler; C. Sneden; J. J. Cowan

    2006-09-18T23:59:59.000Z

    Radiative lifetimes, accurate to +/- 5%, have been measured for 49 even-parity and 14 odd-parity levels of Gd II using laser-induced fluorescence. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 611 lines of Gd II. This work is the largest-scale laboratory study to date of Gd II transition probabilities and the first using a high performance Fourier transform spectrometer. This improved data set has been used to determine a new solar photospheric Gd abundance, log epsilon = 1.11 +/- 0.03. Revised Gd abundances have also been derived for the r-process-rich metal-poor giant stars CS 22892-052, BD+17 3248, and HD 115444. The resulting Gd/Eu abundance ratios are in very good agreement with the solar-system r-process ratio. We have employed the increasingly accurate stellar abundance determinations, resulting in large part from the more precise laboratory atomic data, to predict directly the Solar System r-process elemental abundances for Gd, Sm, Ho and Nd. Our analysis of the stellar data suggests slightly higher recommended values for the r-process contribution and total Solar System values, consistent with the photospheric determinations, for the elements for Gd, Sm, and Ho.

  2. Tsunami and acoustic-gravity waves in water of constant depth

    SciTech Connect (OSTI)

    Hendin, Gali; Stiassnie, Michael [Faculty of Civil and Environmental Engineering, Technion – Israel institute of technology, Haifa 32000 (Israel)] [Faculty of Civil and Environmental Engineering, Technion – Israel institute of technology, Haifa 32000 (Israel)

    2013-08-15T23:59:59.000Z

    A study of wave radiation by a rather general bottom displacement, in a compressible ocean of otherwise constant depth, is carried out within the framework of a three-dimensional linear theory. Simple analytic expressions for the flow field, at large distance from the disturbance, are derived. Realistic numerical examples indicate that the Acoustic-Gravity waves, which significantly precede the Tsunami, are expected to leave a measurable signature on bottom-pressure records that should be considered for early detection of Tsunami.

  3. Brain Tissue Depth (mm) LightPowerDensity(mW/mm2

    E-Print Network [OSTI]

    Schnitzer, Mark

    Brain Tissue Depth (mm) LightPowerDensity(mW/mm2 ) Power Meter Tissue block Bare Fiber = 12° = 6 with the beveled cannula over CeA. d) Chart indicating estimated light power density seen at various distances from the fiber tip in mouse brain tissue when the light power density seen at the fiber tip was 7 mW (~99 mW/mm2

  4. {sup 14}C depth profiles in Apollo 15 and 17 cores and lunar rock 68815

    SciTech Connect (OSTI)

    Jull, A.J.T.; Cloudt, S.; Donahue, D.J. [Univ. of Arizona, Tucson, AZ (United States). NSF Arizona AMS Facility] [Univ. of Arizona, Tucson, AZ (United States). NSF Arizona AMS Facility; Sisterson, J.M. [Harvard Univ., Cambridge, MA (United States). Harvard Cyclotron Lab.] [Harvard Univ., Cambridge, MA (United States). Harvard Cyclotron Lab.; Reedy, R.C. [Los Alamos National Lab., NM (United States)] [Los Alamos National Lab., NM (United States); Masarik, J. [Comenius Univ., Bratislava (Slovakia). Dept. of Nuclear Physics] [Comenius Univ., Bratislava (Slovakia). Dept. of Nuclear Physics

    1998-09-01T23:59:59.000Z

    Accelerator mass spectrometry (AMS) was used to measure the activity vs. depth profiles of {sup 14}C produced by both solar cosmic rays (SCR) and galactic cosmic rays (GCR) in Apollo 15 lunar cores 15001-6 and 15008, Apollo 17 core 76001, and lunar rock 68815. Calculated GCR production rates are in good agreement with {sup 14}C measurements at depths below {approximately}10 cm. Carbon-14 produced by solar protons was observed in the top few cm of the Apollo 15 cores and lunar rock 68815, with near-surface values as high as 66 dpm/kg in 68815. Only low levels of SCR-produced {sup 14}C were observed in the Apollo 17 core 76001. New cross sections for production of {sup 14}C by proton spallation on O, Si, Al, Mg, Fe, and Ni were measured using AMS. These cross sections are essential for the analysis of the measured {sup 14}C depth profiles. The best fit to the activity-depth profiles for solar-proton-produced {sup 14}C measured in the tops of both the Apollo 15 cores and 68815 was obtained for an exponential rigidity spectral shape R{sub 0} of 110--115 MV and a 4 {pi} flux (J{sub 10}, Ep > 10 MeV) of 103--108 protons/cm{sup 2}/s. These values of R{sub 0} are higher, indicating a harder rigidity, and the solar-proton fluxes are higher than those determined from {sup 10}Be, {sup 26}Al, and {sup 53}Mn measurements.

  5. Long-Term Stewardship Baseline Report and Transition Guidance

    SciTech Connect (OSTI)

    Kristofferson, Keith

    2001-11-01T23:59:59.000Z

    Long-term stewardship consists of those actions necessary to maintain and demonstrate continued protection of human health and the environment after facility cleanup is complete. As the Department of Energy’s (DOE) lead laboratory for environmental management programs, the Idaho National Engineering and Environmental Laboratory (INEEL) administers DOE’s long-term stewardship science and technology efforts. The INEEL provides DOE with technical, and scientific expertise needed to oversee its long-term environmental management obligations complexwide. Long-term stewardship is administered and overseen by the Environmental Management Office of Science and Technology. The INEEL Long-Term Stewardship Program is currently developing the management structures and plans to complete INEEL-specific, long-term stewardship obligations. This guidance document (1) assists in ensuring that the program leads transition planning for the INEEL with respect to facility and site areas and (2) describes the classes and types of criteria and data required to initiate transition for areas and sites where the facility mission has ended and cleanup is complete. Additionally, this document summarizes current information on INEEL facilities, structures, and release sites likely to enter long-term stewardship at the completion of DOE’s cleanup mission. This document is not intended to function as a discrete checklist or local procedure to determine readiness to transition. It is an overarching document meant as guidance in implementing specific transition procedures. Several documents formed the foundation upon which this guidance was developed. Principal among these documents was the Long-Term Stewardship Draft Technical Baseline; A Report to Congress on Long-Term Stewardship, Volumes I and II; Infrastructure Long-Range Plan; Comprehensive Facility Land Use Plan; INEEL End-State Plan; and INEEL Institutional Plan.

  6. A Load-based Depth-sensing Indentation Technique for NDE and Life Assessment of Thermal Barrier Coatings

    SciTech Connect (OSTI)

    B. S.-J. Kang; C. Feng; J. M. Tannenbaum; M.A. Alvin

    2009-06-12T23:59:59.000Z

    In this paper, we present a load-based micro-indentation technique for evaluating material mechanical properties as well as degradation evaluation and debonding/spallation detection of thermal barrier coating (TBC) materials. Instead of using contact area as a necessary parameter, the new technique is based on the indentation load. Coupled with a multiple-partial unloading procedure during the indentation process, this technique results in a load-depth sensing indentation system capable of determining Young’s modulus of metals, superalloys, and single crystal matrices, and stiffness of coated material systems with flat, tubular, or curved architectures. This micro-indentation technique can be viewed as a viable non-destructive evaluation (NDE) technique for determining as-manufactured and process-exposed metal, superalloy, single crystal, and TBC-coated material properties. This technique also shows promise for the development of a portable instrument for on-line, in-situ NDE and mechanical properties measurement of structural components.

  7. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Third Evaluation Report and Appendices

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2008-07-01T23:59:59.000Z

    This report describes operations at Alameda-Contra Costa Transit district for three protoype fuel cell buses and six diesel buses operating from the same location.

  8. Dynamics in the Metabasin Space of a Lennard-Jones Glass Former: Connectivity and Transition Rates

    E-Print Network [OSTI]

    Yasheng Yang; Bulbul Chakraborty

    2008-11-17T23:59:59.000Z

    Using simulations, we construct the effective dynamics in metabasin space for a Lennard-Jones glass-former. Metabasins are identified via a scheme that measures transition rates between inherent structures, and generates clusters of inherent structures by drawing in branches that have the largest transition rates. The effective dynamics is shown to be Markovian but differs significantly from the simplest trap models. We specifically show that retaining information about the connectivity in metabasin space is crucial for reproducing the slow dynamics observed in this system.

  9. Letter Report: Borehole Flow and Horizontal Hydraulic Conductivity with Depth at Well ER-12-3

    SciTech Connect (OSTI)

    P. Oberlander; C. Russell

    2005-09-01T23:59:59.000Z

    Borehole flow and fluid temperature during pumping were measured at well ER-12-3 at the Nevada Test Site in Nye County, Nevada. This well was constructed to characterize the carbonate aquifer. The well is cased from land surface to the total depth at 1,487 m (4,880 ft) below ground surface (bgs). Slotted screen is placed in an upper screened section from 1,095 to 1,160 m bgs (3,591 to 3,805 ft bgs) and in the lower screened section from 1,278 to 1,474 m bgs (4,191 to 4,834 ft bgs). Borehole flow velocity (LT-1) with depth was measured with an impeller flowmeter from the top of the screened section to the maximum accessible depth while the well was pumped and under ambient conditions. A complicating factor to data interpretation is that the well was not filter packed and there is significant upward and downward vertical flow in the open annulus under ambient and pumping conditions. The open annulus and large vertical flow velocities in the well casing result in the measured borehole flow rates being potentially highly nonrepresentative of conditions in the aquifer. Hydraulic conductivities calculated under these conditions would require unsupportable assumptions and would be subject to very large uncertainties. Borehole hydraulic conductivities are not presented under these conditions.

  10. Letter Report: Borehole Flow and Horizontal Hydraulic Conductivity with Depth at Well ER-12-4

    SciTech Connect (OSTI)

    Phil L. Oberlander; Charles E. Russell

    2005-12-31T23:59:59.000Z

    Borehole flow and fluid temperature during pumping were measured at well ER-12-4 at the Nevada Test Site in Nye County, Nevada. This well was constructed to characterize the carbonate aquifer. The well is cased from land surface to the total depth at 1,132 m (3,713 ft bgs) below ground surface (bgs). The screened section of the well consists of alternating sections of slotted well screen and blank casing from 948 to 1,132 m bgs (3,111 to 3,713 ft bgs). Borehole flow velocity (LT-1) with depth was measured with an impeller flowmeter from the top of the screened section to the maximum accessible depth while the well was pumped and under ambient conditions. A complicating factor to data interpretation is that the well was not filter packed and there is upward and downward vertical flow in the open annulus under ambient and pumping conditions. The open annulus in the well casing likely causes the calculated borehole flow rates being highly nonrepresentative of inflow from the formation. Hydraulic conductivities calculated under these conditions would require unsupportable assumptions and would be subject to very large uncertainties. Borehole hydraulic conductivities are not presented under these conditions.

  11. Method for the depth corrected detection of ionizing events from a co-planar grids sensor

    DOE Patents [OSTI]

    De Geronimo, Gianluigi (Syosset, NY); Bolotnikov, Aleksey E. (South Setauket, NY); Carini, Gabriella (Port Jefferson, NY)

    2009-05-12T23:59:59.000Z

    A method for the detection of ionizing events utilizing a co-planar grids sensor comprising a semiconductor substrate, cathode electrode, collecting grid and non-collecting grid. The semiconductor substrate is sensitive to ionizing radiation. A voltage less than 0 Volts is applied to the cathode electrode. A voltage greater than the voltage applied to the cathode is applied to the non-collecting grid. A voltage greater than the voltage applied to the non-collecting grid is applied to the collecting grid. The collecting grid and the non-collecting grid are summed and subtracted creating a sum and difference respectively. The difference and sum are divided creating a ratio. A gain coefficient factor for each depth (distance between the ionizing event and the collecting grid) is determined, whereby the difference between the collecting electrode and the non-collecting electrode multiplied by the corresponding gain coefficient is the depth corrected energy of an ionizing event. Therefore, the energy of each ionizing event is the difference between the collecting grid and the non-collecting grid multiplied by the corresponding gain coefficient. The depth of the ionizing event can also be determined from the ratio.

  12. Stochastic estimation of aquifer geometry using seismic refraction data with borehole depth constraints

    SciTech Connect (OSTI)

    Chen, Jinsong [Lawrence Berkeley National Laboratory (LBNL); Hubbard, Susan S [Lawrence Berkeley National Laboratory (LBNL); Korneev, V. [Lawrence Berkeley National Laboratory (LBNL); Gaines, David [University of Tennessee; Baker, Gregory S. [University of Tennessee; Watson, David [ORNL

    2010-11-01T23:59:59.000Z

    We develop a Bayesian model to invert surface seismic refraction data with depth constraints from boreholes for characterization of aquifer geometry and apply it to seismic and borehole data sets collected at the contaminated Oak Ridge National Laboratory site in Tennessee. Rather than the traditional approach of first inverting the seismic arrival times for seismic velocity and then using that information to aid in the spatial interpolation of wellbore data, we jointly invert seismic first arrival time data and wellbore based information, such as depths of key lithological boundaries. We use a staggered grid finite difference algorithm with second order accuracy in time and fourth order accuracy in space to model seismic full waveforms and use an automated method to pick the first arrival times. We use Markov Chain Monte Carlo methods to draw many samples from the joint posterior probability distribution, on which we can estimate the key interfaces and their associated uncertainty as a function of horizontal location and depth. We test the developed method on both synthetic and field case studies. The synthetic studies show that the developed method is effective at rigorous incorporation of multiscale data and the Bayesian inversion reduces uncertainty in estimates of aquifer zonation. Applications of the approach to field data, including two surface seismic profiles located 620 m apart from each other, reveal the presence of a low velocity subsurface zone that is laterally persistent. This geophysically defined feature is aligned with the plume axis, suggesting it may serve as an important regional preferential flow pathway.

  13. Effects of realistic tensor force on nuclear structure

    SciTech Connect (OSTI)

    Nakada, H. [Department of Physics, Graduate School of Science, Chiba University, Inage, Chiba 263-8522 (Japan)

    2012-10-20T23:59:59.000Z

    First-order tensor-force effects on nuclear structure are investigated in the self-consistent mean-field and RPA calculations with the M3Y-type semi-realistic interactions, which contain the realistic tensor force. The tensor force plays a key role in Z- or N-dependence of the shell structure, and in transitions involving spin degrees-of-freedom. It is demonstrated that the semi-realistic interactions successfully describe the N-dependence of the shell structure in the proton-magic nuclei (e.g. Ca and Sn), and the magnetic transitions (e.g. M1 transition in {sup 208}Pb).

  14. IMAGE BASED RENDERING WITH DEPTH CAMERAS: HOW MANY ARE NEEDED? Christopher Gilliam, James Pearson, Mike Brookes and Pier Luigi Dragotti

    E-Print Network [OSTI]

    Dragotti, Pier Luigi

    IMAGE BASED RENDERING WITH DEPTH CAMERAS: HOW MANY ARE NEEDED? Christopher Gilliam, James Pearson London Exhibition Road, SW7 2AZ, London, United Kingdom. ABSTRACT Image based rendering is a technique of traditional color images with depth images. This combination promises to improve the rendering quality

  15. Comparison of Air Fluorescence and Ionization Measurements of E.M. Shower Depth Profiles: Test of a UHECR Detector Technique

    SciTech Connect (OSTI)

    Belz, J.; Cao, Z.; Huentemeyer, P.; Jui, C.C.H.; Martens, K.; Matthews, J.; Maestas, M.; Smith, J.; Sokolsky, P.; Springer, R.W.; Thomas, J.; Thomas, S.; /Utah U.; Chen,P.; Field, Clive; Hast, C.; Iverson, R.; Ng, J.S.T.; Odian, A.; Reil, K.; Vincke, H.; Walz, D.; /SLAC /Montana U. /Rutgers U., Piscataway /Taiwan, Natl. Taiwan U.; ,

    2005-10-07T23:59:59.000Z

    Measurements are reported on the fluorescence of air as a function of depth in electromagnetic showers initiated by bunches of 28.5 GeV electrons. The light yield is compared with the expected and observed depth profiles of ionization in the showers. It validates the use of atmospheric fluorescence profiles in measuring ultra high energy cosmic rays.

  16. American Public Opinion on Global Warming in the American States: An In-Depth Study of Florida, Maine, and Massachusetts

    E-Print Network [OSTI]

    Ford, Andrew

    1 American Public Opinion on Global Warming in the American States: An In-Depth Study of Florida Public Opinion on Global Warming in the American States: An In-Depth Study of Florida, Maine warming has been happening · What might have caused global warming · Whether global warming

  17. Transit Detection of Radial Velocity Planets

    E-Print Network [OSTI]

    Stephen R. Kane; Kaspar von Braun

    2008-06-30T23:59:59.000Z

    The orbital parameters of extra-solar planets have a significant impact on the probability that the planet will transit the host star. This was recently demonstrated by the transit detection of HD 17156b whose favourable eccentricity and argument of periastron dramatically increased its transit likelihood. We present a study which provides a quantitative analysis of how these two orbital parameters effect the geometric transit probability as a function of period. Further, we apply these results to known radial velocity planets and show that there are unexpectedly high transit probabilities for planets at relatively long periods. For a photometric monitoring campaign which aims to determine if the planet indeed transits, we calculate the significance of a null result and the subsequent constraints that may be applied to orbital parameters.

  18. Offshore structures can be subjected to millions of variable amplitude load cycles during their service life which is the primary cause of structural deterioration. Such

    E-Print Network [OSTI]

    Boyer, Edmond

    ABSTRACT Offshore structures can be subjected to millions of variable amplitude load cycles during and methods coupled with a growing appetite to exploit the bountiful offshore energy resources has lead to the installation of more and more offshore structures and at greater depths. These structures can experience

  19. Uranium Speciation As a Function of Depth in Contaminated Hanford Sediments - A Micro-XRF, Micro-XRD, and Micro- And Bulk-XAFS Study

    SciTech Connect (OSTI)

    Singer, David M.; Zachara, John M.; Brown, Gordon E.

    2009-02-01T23:59:59.000Z

    Processing ponds at the Hanford, Washington Area 300 site were used for storing basic sodium aluminate and acidic U(VI)-Cu(II)-containing waste from 1943 to 1975. One result of this use is a groundwater plume containing elevated levels of U and Cu beneath the dry ponds and adjacent to the Columbia River. We have used synchrotron-based micro-X-ray fluorescence (?XRF) imaging, micro-X-ray absorption fine structure (?XANES) spectroscopy, and micro-X-ray diffraction (?XRD) techniques combined with bulk U LIII-edge X-ray absorption fine structure (XAFS) spectroscopy to determine the distribution and speciation of U and Cu through the vadose and groundwater zones beneath North Processing Pond #2 (NPP2). Sediment samples were collected from the vadose zone (8’ and 12’ depths), and a sample from the groundwater zone was collected just below the water table (12’-14’ depth). ?XRF imaging revealed two major U occurrences within the vadose and groundwater zones: (1) low to moderate concentrations of U(VI) associated with mineral surfaces (particularly chlorite), and (2) high concentration U(VI)-containing micron-sized particles associated with surface coatings on grains of muscovite and chlorite. These U(VI) hot spots are frequently spatially correlated with Cu(II) hot spots. In the groundwater zone, these particles were identified as the copper-uranyl-silicate cuprosklodowskite and the cupper-uranyl-phosphate metatorbernite. In contrast, the U-Cu-containing particles are X-ray amorphous in the vadose zone. Fits of U LIII-edge XAFS spectra by linear-combination fitting indicate that U speciation consists of ~ 75% uranyl sorbed to clays and ~25% metatorbernite-like X-ray amorphous U-Cu-phosphates (8’ depth); nearly 100% sorbed uranyl (12’ depth); and ~70% sorbed uranyl and ~30% cuprosklodowskite/metatorbernite (ground water zone). These findings suggest that the dissolution of U(VI)-Cu(II)-bearing solids as well as the desorption of U(VI), mainly from phyllosilicates, are important sources of U(VI) in the Area 300 groundwater plume.

  20. Hydrogen Infrastructure Transition Analysis: Milestone Report

    SciTech Connect (OSTI)

    Melendez, M.; Milbrandt, A.

    2006-01-01T23:59:59.000Z

    This milestone report identifies a minimum infrastructure that could support the introduction of hydrogen vehicles and develops and evaluates transition scenarios supported by this infrastructure.

  1. Detecting New Planets in Transiting Systems

    E-Print Network [OSTI]

    Jason H. Steffen

    2006-09-18T23:59:59.000Z

    I present an initial investigation into a new planet detection technique that uses the transit timing of a known, transiting planet. The transits of a solitary planet orbiting a star occur at equally spaced intervals in time. If a second planet is present, dynamical interactions within the system will cause the time interval between transits to vary. These transit time variations can be used to infer the orbital elements of the unseen, perturbing planet. I show analytic expressions for the amplitude of the transit time variations in several limiting cases. Under certain conditions the transit time variations can be comparable to the period of the transiting planet. I also present the application of this planet detection technique to existing transit observations of the TrES-1 and HD209458 systems. While no convincing evidence for a second planet in either system was found from those data, I constrain the mass that a perturbing planet could have as a function of the semi-major axis ratio of the two planets and the eccentricity of the perturbing planet. Near low-order, mean-motion resonances (within about 1% fractional deviation), I find that a secondary planet must generally have a mass comparable to or less than the mass of the Earth--showing that these data are the first to have sensitivity to sub Earth-mass planets orbiting main sequence stars. These results show that TTV will be an important tool in the detection and characterization of extrasolar planetary systems.

  2. Sandia National Laboratories: electronic conducting transition...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electronic conducting transition metal oxides Joint Hire Increases Materials Science Collaboration for Sandia, UNM On September 16, 2014, in Advanced Materials Laboratory,...

  3. Identifying Transition State Features of Enzymatic Conformational...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Identifying Transition State Features of Enzymatic Conformational Cycles Thursday, January 5, 2012 - 11:00am SSRL Conference Room 137-322 Dr. Dimitar Pachov, HHMI Research...

  4. Transition Metal Dopants Essential for Producing Ferromagnetism...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Metal Dopants Essential for Producing Ferromagnetism in Metal Oxide Nanoparticles. Transition Metal Dopants Essential for Producing Ferromagnetism in Metal Oxide Nanoparticles....

  5. AVTA: Transit Vehicle Specifications and Test Procedures

    Broader source: Energy.gov [DOE]

    All Advanced Vehicle Testing Activity transit projects follow a rigorous data collection and analysis protocol. Refer to "General Evaluation Plan: Fleet Test and Evaluation Projects" for...

  6. Dynamics of stimulated L ? H transitions

    SciTech Connect (OSTI)

    Miki, K. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of) [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Center for Computational Science and e-Systems, Japan Atomic Energy Agency, Chiba 277-8587 (Japan); Diamond, P. H.; Xiao, W. W. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of) [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Center for Momentum Transport and Flow Organization, University of California, San Diego, California 92093 (United States); Hahn, S.-H. [KSTAR Team, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)] [KSTAR Team, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Gürcan, Ö. D. [LPP, Ecole Polytechnique, CNRS, 92118 Palaiseau Cedex (France)] [LPP, Ecole Polytechnique, CNRS, 92118 Palaiseau Cedex (France); Tynan, G. R. [Center for Momentum Transport and Flow Organization, University of California, San Diego, California 92093 (United States)] [Center for Momentum Transport and Flow Organization, University of California, San Diego, California 92093 (United States)

    2013-08-15T23:59:59.000Z

    We report on model studies of stimulated L ? H transitions [K. Miki et al., Phys. Rev. Lett. 110, 195002 (2013)]. These studies use a reduced mesoscale model. Model studies reveal that L ? H transition can be triggered by particle injection into a subcritical state (i.e., Ptransition. For low ambient heating, strong injection is predicted to trigger a transient turbulence collapse. Repetitive injection at a period less than the lifetime of the collapsed state can thus maintain the turbulence collapse and so sustain a driven H-mode-like state. The total number of particles required to induce a transition by either injection or gas puffing is estimated. Results indicate that the total number of injected particles required is much smaller than that required for a transition by gas puffing. We thus show that internal injection is more efficient than gas puffing of comparable strength. We also observe that zonal flows do not play a critical role in stimulated transitions. For spontaneous transitions, the spike of the Reynolds work of turbulence on the zonal flow precedes the spike in the mean electric field shear. In contrast, we show that the two are coincident for stimulated transitions, suggesting that there is no causal link between zonal and mean flows for stimulated transitions.

  7. Aspects of the non-zonal transition

    SciTech Connect (OSTI)

    Pueschel, M. J.; Terry, P. W. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)] [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Hatch, D. R. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)] [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)

    2014-05-15T23:59:59.000Z

    The non-zonal transition, a process which can bring about very large heat fluxes in gyrokinetic simulations, occurs once a certain threshold plasma ? is reached. This threshold is parameterized via a simulation database, yielding an expression estimating at what ? a given system may approach the transition. Furthermore, the diffusive outward transport of a heat blob in a temperature profile marginally stable with respect to the non-zonal transition is discussed: the resulting transport timescale combines the underlying turbulent transport timescale and the linear instability growth time, thus demonstrating that the non-zonal transition provides a mechanism for very fast heat dissipation.

  8. DOE Hydrogen Transition Analysis Workshop Discussion Comments...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Workshop Discussion Comments, Questions, and Action Items DOE Hydrogen Transition Analysis Workshop Discussion Comments, Questions, and Action Items Discussion comments, questions,...

  9. Energy Transition Initiative: Islands Playbook (Book) | OSTI...

    Office of Scientific and Technical Information (OSTI)

    Energy Transition Initiative: Islands Playbook (Book) Re-direct Destination: The Island Energy Playbook (the Playbook) provides an action-oriented guide to successfully initiating,...

  10. Structure and kinematics of the Suzume fault, Okitsu melange, Shimanto accretionary complex, Japan

    E-Print Network [OSTI]

    Kanaya, Takamasa

    2007-04-25T23:59:59.000Z

    underplated to the prism along the subduction plate-boundary at seismogenic depth. An internal, horsebounding thrust of the duplex, referred to as the Suzume fault, juxtaposes basalt in the hanging wall and sedimentary rocks in the footwall. Structure...

  11. The Video Mesh: A Data Structure for Image-based Video Editing

    E-Print Network [OSTI]

    Durand, Fredo

    2009-12-16T23:59:59.000Z

    This paper introduces the video mesh, a data structure for representing video as 2.5D "paper cutouts." The video mesh allows interactive editing of moving objects and modeling of depth, which enables 3D effects and ...

  12. The Video Mesh: A Data Structure for Image-based Three-dimensional Video Editing

    E-Print Network [OSTI]

    Chen, Jiawen

    This paper introduces the video mesh, a data structure for representing video as 2.5D “paper cutouts.” The video mesh allows interactive editing of moving objects and modeling of depth, which enables 3D effects and ...

  13. PUREX transition project case study

    SciTech Connect (OSTI)

    Jasen, W.G.

    1996-04-15T23:59:59.000Z

    In December 1992, the US Department of Energy (DOE) directed that the Plutonium-Uranium Extraction (PUREX) Plant be shut down and deactivated because it was no longer needed to support the nation`s production of weapons-grade plutonium. The PUREX/UO{sub 2} Deactivation Project will establish a safe and environmentally secure configuration for the facility and preserve that configuration for 10 years. The 10-year span is used to predict future maintenance requirements and represents the estimated time needed to define, authorize, and initiate the follow-on decontamination and decommissioning activities. Accomplishing the deactivation project involves many activities. Removing major hazards, such as excess chemicals, spent fuel, and residual plutonium are major goals of the project. The scope of the PUREX Transition Project is described within.

  14. Dynamical transitions of turing patterns.

    SciTech Connect (OSTI)

    Kaper, H. G.; Wang, S.; Yari, M.; Mathematics and Computer Science; Indiana Univ.

    2009-01-01T23:59:59.000Z

    This paper is concerned with the formation and persistence of spatiotemporal patterns in binary mixtures of chemically reacting species, where one of the species is an activator, the other an inhibitor of the chemical reaction. The system of reaction-diffusion equations is reduced to a finite system of ordinary differential equations by a variant of the centre-manifold reduction method. The reduced system fully describes the local dynamics of the original system near transition points at the onset of instability. The attractor-bifurcation theory is used to give a complete characterization of the bifurcated objects in terms of the physical parameters of the problem. The results are illustrated for the Schnakenberg model.

  15. Glass Transition, Cooperativity and Interfaces

    E-Print Network [OSTI]

    Salez, Thomas; Dalnoki-Veress, Kari; Raphaël, Elie; Forrest, James A

    2015-01-01T23:59:59.000Z

    We introduce a minimal theory of glass formation based on the physical ideas of molecular crowding and resultant cooperative motion, and address the effects of free interfaces on dynamics. First, we obtain a simple scaling expression for the diverging number of particles taking part in bulk cooperative relaxation as the system approaches kinetic arrest, and in doing so provide a robust derivation of the Adam and Gibbs description of cooperative dynamics. Then, by including thermal expansivity of the material, the Vogel-Fulcher-Tammann relation is derived. Moreover, we predict a temperature-dependent expression for the cooperative length $\\xi$ of bulk relaxation, and explore the influence of sample boundaries on the glassy dynamics when the system size becomes comparable to $\\xi$. The theory is in full agreement with measurements of the glass transition temperature of thin polystyrene films. This agreement comes with two adjustable parameters, the critical interparticle distance and the Vogel temperature. Alth...

  16. Dynamical Transition and Heterogeneous Hydration Dynamics in RNA

    E-Print Network [OSTI]

    Jeseong Yoon; Jong-Chin Lin; Changbong Hyeon; D. Thirumalai

    2014-04-24T23:59:59.000Z

    Enhanced dynamical fluctuations of RNAs, facilitated by a network of water molecules with strong interactions with RNA, are suspected to be critical in their ability to respond to a variety of cellular signals. Using atomically detailed molecular dynamics simulations at various temperatures of purine (adenine)- and preQ$_1$ sensing riboswitch aptamers, we show that water molecules in the vicinity of RNAs undergo complex dynamics depending on the local structures of the RNAs. The overall lifetimes of hydrogen bonds (HBs) of surface bound waters are more than at least 1-2 orders of magnitude longer than bulk water. Slow hydration dynamics, revealed in non-Arrhenius behavior of the relaxation time, arises from high activation barriers to break water hydrogen bonds with a nucleotide and by reduced diffusion of water. The relaxation kinetics at specific locations in the two RNAs show a broad spectrum of time scales reminiscent of glass-like behavior, suggesting that the hydration dynamics is highly heterogeneous. Both RNAs undergo dynamic transition at $T = T_D \\gtrsim 200$ K as assessed by the mean square fluctuation of hydrogen atoms $\\langle x^2\\rangle$, which undergoes an abrupt harmonic-to-anharmonic transition at $T_D$. The near universal value of $T_D$ found for these RNAs and previously for tRNA is strongly correlated with changes in hydration dynamics as $T$ is altered. Hierarchical dynamics of waters associated with the RNA surface, revealed in the motions of distinct classes of water with well-separated time scales, reflects the heterogeneous local environment on the molecular surface of RNA. At low temperatures slow water dynamics predominates over structural transitions. Our study demonstrates that the complex interplay of dynamics between water and local environment in the RNA structures could be a key determinant of the functional activities of RNA.

  17. Hf Transition Probabilities and Abundances

    E-Print Network [OSTI]

    J. E. Lawler; E. A. Den Hartog; Z. E. Labby; C. Sneden; J. J. Cowan; I. I. Ivans

    2006-11-01T23:59:59.000Z

    Radiative lifetimes from laser-induced fluorescence measurements, accurate to about +/- 5 percent, are reported for 41 odd-parity levels of Hf II. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 150 lines of Hf II. Approximately half of these new transition probabilities overlap with recent independent measurements using a similar approach. The two sets of measurements are found to be in good agreement for measurements in common. Our new laboratory data are applied to refine the hafnium photospheric solar abundance and to determine hafnium abundances in 10 metal-poor giant stars with enhanced r-process abundances. For the Sun we derive log epsilon (Hf) = 0.88 +/- 0.08 from four lines; the uncertainty is dominated by the weakness of the lines and their blending by other spectral features. Within the uncertainties of our analysis, the r-process-rich stars possess constant Hf/La and Hf/Eu abundance ratios, log epsilon (Hf/La) = -0.13 +/- 0.02 (sigma = 0.06) and log epsilon (Hf/Eu) = +0.04 +/- 0.02 (sigma = 0.06). The observed average stellar abundance ratio of Hf/Eu and La/Eu is larger than previous estimates of the solar system r-process-only value, suggesting a somewhat larger contribution from the r-process to the production of Hf and La. The newly determined Hf values could be employed as part of the chronometer pair, Th/Hf, to determine radioactive stellar ages.

  18. Lattice Vibrations and Superconductivity in Layered Structures

    E-Print Network [OSTI]

    Allen, Roland E.; Alldredg, GP; WETTE, FWD.

    1970-01-01T23:59:59.000Z

    PHYSICAL REVIEW B VOLUME 2, NUMBER 7 1 OCTOB ER, 1970 Lattice Vibrations and Superconductivity in Layered Structures* B. E. Allen, G. P. Alldredge, and F. W. de bette DePartment of Physics, University of Texas, Austin, Texas 78712 (Received 18... May 1970) In order to estimate the influence of both surface and interface effects on phonon frequencies and superconducting transition temperatures in layered structures, we have calculated the vibrational modes of structures composed...

  19. Determining Transition State Geometries in Liquids Using 2D-IR

    SciTech Connect (OSTI)

    Harris, Charles; Cahoon, James F.; Sawyer, Karma R.; Schlegel, Jacob P.; Harris, Charles B.

    2007-12-11T23:59:59.000Z

    Many properties of chemical reactions are determined by the transition state connecting reactant and product, yet it is difficult to directly obtain any information about these short-lived structures in liquids. We show that two-dimensional infrared (2D-IR) spectroscopy can provide direct information about transition states by tracking the transformation of vibrational modes as a molecule crossed a transition state. We successfully monitored a simple chemical reaction, the fluxional rearrangement of Fe(CO)5, in which the exchange of axial and equatorial CO ligands causes an exchange of vibrational energy between the normal modes of the molecule. This energy transfer provides direct evidence regarding the time scale, transition state, and mechanism of the reaction.

  20. Lifshitz and Excited State Quantum Phase Transitions in Microwave Dirac Billiards

    E-Print Network [OSTI]

    B. Dietz; M. Miski-Oglu; N. Pietralla; A. Richter; L. von Smekal; J. Wambach; F. Iachello

    2013-09-03T23:59:59.000Z

    We present experimental results for the density of states (DOS) of a superconducting microwave Dirac billiard which serves as an idealized model for the electronic properties of graphene. The DOS exhibits two sharp peaks which evolve into van Hove singularities with increasing system size. They divide the band structure into regions governed by the \\emph{relativistic} Dirac equation and by the \\emph{non-relativistic} Schr\\"odinger equation, respectively. We demonstrate that in the thermodynamic limit a topological transition appears as a neck-disrupting Lifshitz transition in the number susceptibility and as an excited state transition in the electronic excitations. Furthermore, we recover the finite-size scaling typical for excited state quantum phase transitions involving logarithmic divergences and identify a quasi-order parameter.