Sample records for bi uup se

  1. New Rate Schedule CV-UUP1 UNITED STATES DEPARTMENT OF ENERGY

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

    UUP1 UNITED STATES DEPARTMENT OF ENERGY WESTERN AREA POWER ADMINISTRATION CENTRAL VALLEY PROJECT SCHEDULE OF RATE FOR UNRESERVED USE PENALTIES Effective: October 1, 2011, through...

  2. Bi-Se doped with Cu, p-type semiconductor

    DOE Patents [OSTI]

    Bhattacharya, Raghu Nath; Phok, Sovannary; Parilla, Philip Anthony

    2013-08-20T23:59:59.000Z

    A Bi--Se doped with Cu, p-type semiconductor, preferably used as an absorber material in a photovoltaic device. Preferably the semiconductor has at least 20 molar percent Cu. In a preferred embodiment, the semiconductor comprises at least 28 molar percent of Cu. In one embodiment, the semiconductor comprises a molar percentage of Cu and Bi whereby the molar percentage of Cu divided by the molar percentage of Bi is greater than 1.2. In a preferred embodiment, the semiconductor is manufactured as a thin film having a thickness less than 600 nm.

  3. Electrical Transport of Topological Insulator-Bi2Se3 and Thermoelectric Properties of Graphene

    E-Print Network [OSTI]

    WEI, PENG

    2011-01-01T23:59:59.000Z

    Hall effect and topological insulators. Phys Today Klitzing,L. & Mele, E. J. Topological insulators in three dimensions.Zhang, H. J. et al. Topological insulators in Bi 2 Se 3 , Bi

  4. Native defects in tetradymite Bi2(TexSe3-x) topological insulators

    SciTech Connect (OSTI)

    Wang, Lin-Lin [Ames Laboratory; Huang, Mianliang [South Dakota School of Mines; Thimmaiah, Srinivasa [Ames Laboratory; Alam, Aftab [Ames Laboratory; Budko, Sergey L. [Ames Laboratory; Kaminski, Adam [Ames Laboratory; Lograsso, Thomas A. [Ames Laboratory; Canfield, Paul [Ames Laboratory; Johnson, Duane D. [Ames Laboratory

    2013-03-08T23:59:59.000Z

    Formation energies of native defects in Bi2(TexSe3-x), with comparison to ideal Bi2Te2S, are calculated in density-functional theory to assess transport properties. Bi2Se3 is found to be n type for both Bi- and Se-rich growth conditions, while Bi2Te3 changes from n to p type going from Te- to Bi-rich conditions, as observed. Bi2Te2Se and Bi2Te2S are generally n type, explaining observed heavily doped n-type behavior in most samples. A (0/-) transition level at 16 meV above valence-band maximum for Bi on Te antisites in Bi2Te2Se is related to the observed thermally active transport gap causing a p-to-n transition at low temperature. Bi2(TexSe3-x) with x>2 are predicted to have high bulk resistivity due to effective carrier compensation when approaching the n-to-p crossover. Predicted behaviors are confirmed from characterization of our grown single crystals.

  5. Electrical Transport of Topological Insulator-Bi2Se3 and Thermoelectric Properties of Graphene

    E-Print Network [OSTI]

    WEI, PENG

    2011-01-01T23:59:59.000Z

    tapes are detached to exfoliate the crystal into thinnercan also be utilized to exfoliate Bi 2 Se 3 on top of SrTiO

  6. Micro-Raman spectroscopy of mechanically exfoliated few-quintuple layers of Bi2Te3, Bi2Se3, and Sb2Te3 materials

    E-Print Network [OSTI]

    Micro-Raman spectroscopy of mechanically exfoliated few-quintuple layers of Bi2Te3, Bi2Se3, and Sb2-like" exfoliated few-quintuple layers of Bi2Te3, Bi2Se3, and Sb2Te3. It is found that crystal symmetry breaking

  7. Ultrathin Topological Insulator Bi2Se3 Nanoribbons Exfoliated by Atomic Force

    E-Print Network [OSTI]

    Cui, Yi

    Ultrathin Topological Insulator Bi2Se3 Nanoribbons Exfoliated by Atomic Force Microscopy Seung Sae, Stanford University, Stanford, California 94305 ABSTRACT Ultrathin topological insulator nanostructures), the layered bismuth selenide (Bi2Se3), a single Dirac-cone topological insulator with a large bulk gap, can

  8. Polarization dependent photocurrents in thin films of the topological insulator Bi?Se?

    E-Print Network [OSTI]

    Lau, Claudia (Claudia M.)

    2012-01-01T23:59:59.000Z

    Topological insulators are a new class of three-dimensional quantum materials whose interior or bulk is an insulator but whose surface is a conductor. Bi?Se? is a prototypical topological insulator that physicists at MIT ...

  9. A comparative transport study of Bi{sub 2}Se{sub 3} and Bi{sub 2}Se{sub 3}/yttrium iron garnet

    SciTech Connect (OSTI)

    Jiang, Zilong; Tang, Chi; Shi, Jing [Department of Physics and Astronomy, University of California, Riverside, California 92521 (United States); Katmis, Ferhat; Wei, Peng; Moodera, Jagadeesh S. [Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2014-06-02T23:59:59.000Z

    Bilayers of 20 quintuple layer Bi{sub 2}Se{sub 3} on 30?nm thick yttrium iron garnet (YIG) have been grown with molecular beam epitaxy in conjunction with pulsed laser deposition. The presence of the ferri-magnetic insulator YIG causes additional scattering to the surface states of the Bi{sub 2}Se{sub 3} topological insulator layer, as indicated by the temperature dependence of the resistivity. From the two-channel analysis of the Hall data, we find that the surface contribution in the bilayer samples is greatly reduced. Furthermore, the weak antilocalization effect from the surface states is clearly suppressed due to the presence of the YIG layer.

  10. Three-dimensional topological insulators Bi{sub 2}Te{sub 3}, Bi{sub 2}Se{sub 3}, and Bi{sub 2}Te{sub 2}Se - a microwave spectroscopy study

    SciTech Connect (OSTI)

    Wolos, A. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland and Faculty of Physics, University of Warsaw, ul Hoza 69, 00-681 Warsaw (Poland); Drabinska, A.; Szyszko, S.; Kaminska, M. [Faculty of Physics, University of Warsaw, ul Hoza 69, 00-681 Warsaw (Poland); Strzelecka, S. G.; Hruban, A.; Materna, A.; Piersa, M. [Institute of Electronic Materials Technology, ul. Wolczynska 133, 01-919 Warsaw (Poland)

    2013-12-04T23:59:59.000Z

    We present results of investigations of three-dimensional topological insulators from a family of bismuth compounds performed in electron spin resonance spectrometer. Next to the standard spin resonance spectra in Bi{sub 2}Se{sub 3} originating from bulk conduction electrons (g{sub Verbar;} = 27.5 ± 0.1 and g{sub ?} = 19.5 ± 0.1), we observed also cyclotron resonance due to topological surface states in Bi{sub 2}Te{sub 3} and non-resonant signal related to weak anti-localization in Bi{sub 2}Te{sub 2}Se. The analysis of the cyclotron resonance signal yields low Fermi velocity equal to 3250 m/s in Bi{sub 2}Te{sub 3}. The phase coherence length determined from weak anti-localization signal equals to 550 nm at low temperatures in Bi{sub 2}Te{sub 2}Se. Relation of the signals to bulk, topological surface or two-dimensional quantum well states is discussed and where possible indicated.

  11. Disordered stoichiometric nanorods and ordered off-stoichiometric nanoparticles in n-type thermoelectric Bi?Te?.?Se?.?

    E-Print Network [OSTI]

    Carlton, Chris E.

    N-type Bi?Te?.?Se?.? bulk thermoelectric materials with peak ZT values up to ?1 were examined by transmission electron microscopy and electron diffraction. Two nanostructural features were found: (i) a structural modulation ...

  12. Dependence of superconductivity in CuxBi?Se? on quenching conditions

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

    Schneeloch, J. A.; Zhong, R. D.; Xu, Z. J.; Gu, G. D.; Tranquada, J. M.

    2015-04-01T23:59:59.000Z

    Topological superconductivity, implying gapless protected surface states, has recently been proposed to exist in the compound CuxBi?Se?. Unfortunately, low diamagnetic shielding fractions and considerable inhomogeneity have been reported in this compound. In an attempt to understand and improve on the finite superconducting volume fractions, we have investigated the effects of various growth and post-annealing conditions. With a melt-growth (MG) method, diamagnetic shielding fractions of up to 56% in Cu???Bi?Se? have been obtained, the highest value reported for this method. We investigate the efficacy of various quenching and annealing conditions, finding that quenching from temperatures above 560°C is essential for superconductivity,more »whereas quenching from lower temperatures or not quenching at all is detrimental. A modified floating zone (FZ) method yielded large single crystals but little superconductivity. Even after annealing and quenching, FZ-grown samples had much less chance of being superconducting than MG-grown samples. From the low shielding fractions in FZ-grown samples and the quenching dependence, we suggest that a metastable secondary phase having a small volume fraction in most of the samples may be responsible for the superconductivity.« less

  13. Topological insulators in Bi2Se3, Bi2Te3 and Sb2Te3 with a single Dirac cone on the surface

    SciTech Connect (OSTI)

    Zhang, Haijun; /Beijing, Inst. Phys.; Liu, Chao-Xing; /Tsinghua U., Beijing; Qi, Xiao-Liang; /Stanford U., Phys. Dept.; Dai, Xi; Fang, Zhong; /Beijing, Inst. Phys.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

    2010-02-24T23:59:59.000Z

    Topological insulators are new states of quantum matter in which surface states residing in the bulk insulating gap of such systems are protected by time-reversal symmetry. The study of such states was originally inspired by the robustness to scattering of conducting edge states in quantum Hall systems. Recently, such analogies have resulted in the discovery of topologically protected states in two-dimensional and three-dimensional band insulators with large spin-orbit coupling. So far, the only known three-dimensional topological insulator is Bi{sub x}Sb{sub 1-x}, which is an alloy with complex surface states. Here, we present the results of first-principles electronic structure calculations of the layered, stoichiometric crystals Sb{sub 2}Te{sub 3}, Sb{sub 2}Se{sub 3}, Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3}. Our calculations predict that Sb{sub 2}Te{sub 3}, Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3} are topological insulators, whereas Sb{sub 2}Se{sub 3} is not. These topological insulators have robust and simple surface states consisting of a single Dirac cone at the point. In addition, we predict that Bi{sub 2}Se{sub 3} has a topologically non-trivial energy gap of 0.3 eV, which is larger than the energy scale of room temperature. We further present a simple and unified continuum model that captures the salient topological features of this class of materials.

  14. Surface and substrate induced effects on thin films of the topological insulators Bi2Se3 and Bi2Te3

    SciTech Connect (OSTI)

    Liu, Wenliang [Xiangtan University, Xiangtan Hunan, China; Peng, Xiangyang [Xiangtan University, Xiangtan Hunan, China; Wei, Xiaolin [Xiangtan University, Xiangtan Hunan, China; Yang, Hong [Xiangtan University, Xiangtan Hunan, China; Stocks, George Malcolm [ORNL; Zhong, Jianxin [Xiangtan University, Xiangtan Hunan, China

    2013-01-01T23:59:59.000Z

    Based on van der Waals density functional calculations, we have studied few-quintuple-layer (QL) films of Bi2Se3 and Bi2Te3. The separation between the QLs near the surface is found to have a large increase after relaxation, whereas, the separation between the inner QLs is smaller and approaches the bulk value as the thickness grows, showing a two-dimensional to three-dimensional structural crossover. Accordingly, the surface Dirac cone of the Bi2Se3 film is evidently gapped for small thicknesses (two to four QLs), and the gap is reduced and, finally, is closed with the increasing thickness, agreeing well with the experiments. We further studied the substrate effect by investigating the Bi2Se3/graphene system. It is found that the underlying graphene induces a giant thickness-dependent Rashba splitting and Dirac point shift. Because Bi2Te3 films have smaller relative inter-QL expansion and stronger spin-orbit coupling, the topological features start to appear in the film as thin as two QLs in good accord with the experiments.

  15. PUBLISHED ONLINE: 10 MAY 2009 | DOI: 10.1038/NPHYS1270 Topological insulators in Bi2Se3, Bi2Te3 and Sb2Te3

    E-Print Network [OSTI]

    Loss, Daniel

    ARTICLES PUBLISHED ONLINE: 10 MAY 2009 | DOI: 10.1038/NPHYS1270 Topological insulators in Bi2Se3-Liang Qi3 , Xi Dai1 , Zhong Fang1 and Shou-Cheng Zhang3 * Topological insulators are new states of quantum of topologically protected states in two-dimensional and three-dimensional band insulators with large spin

  16. Synthesis of Bi{sub 2}Se{sub 3} thermoelectric nanosheets and nanotubes through hydrothermal co-reduction method

    SciTech Connect (OSTI)

    Cui Hongmei [State Key Laboratory of Crystal Materials, Shandong University, 27 Shanda Nanlu, Jinan City, Shandong Province 250100 (China); Liu Hong [State Key Laboratory of Crystal Materials, Shandong University, 27 Shanda Nanlu, Jinan City, Shandong Province 250100 (China)]. E-mail: hongliu@sdu.edu.cn; Li Xia [State Key Laboratory of Crystal Materials, Shandong University, 27 Shanda Nanlu, Jinan City, Shandong Province 250100 (China); Wang Jiyang [State Key Laboratory of Crystal Materials, Shandong University, 27 Shanda Nanlu, Jinan City, Shandong Province 250100 (China)]. E-mail: jywang@icm.sdu.edu.cn; Han Feng [State Key Laboratory of Crystal Materials, Shandong University, 27 Shanda Nanlu, Jinan City, Shandong Province 250100 (China); Zhang Xudong [State Key Laboratory of Crystal Materials, Shandong University, 27 Shanda Nanlu, Jinan City, Shandong Province 250100 (China); Boughton, R.I. [Department of Physics and Astronomy, Bowling Green State University, Bowling Green, OH 43403 (United States)

    2004-11-01T23:59:59.000Z

    Bi{sub 2}Se{sub 3} nanosheets and nanotubes were prepared by a hydrothermal co-reduction method at 150, 180, 200, and 210{sup o}C. Bi{sub 2}Se{sub 3} nanosheets, nanobelts and nanotubes were obtained. The Bi{sub 2}Se{sub 3} nanoflakes are 50-500nm in width and 2-5nm in thickness. The Bi{sub 2}Se{sub 3} nanotubes are 5-10nm in diameter, 80-120nm in length, and 1.3nm in wall thickness. X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, and electron diffraction were employed to characterize the products. Experimental results showed that the nanosheets and the nanotubes are hexagonal in structure with a=4.1354A and c=27.4615A. A possible formation and crystal growth mechanism of Bi{sub 2}Se{sub 3} nanostructures is proposed.

  17. The surface-state of the topological insulator Bi2Se3 revealed by cyclotron resonance

    SciTech Connect (OSTI)

    Mcdonald, Ross D [Los Alamos National Laboratory; Ayala - Valenzuela, Oscar E [Los Alamos National Laboratory; Altarawneh, Moaz M [Los Alamos National Laboratory; Analytis, James G [STANFORD UNIV/SLAC; Chu, J. H. [STANFORD UNIV/SLAC; Fisher, R. [STANFORD UNIV/SLAC

    2011-01-14T23:59:59.000Z

    Transport measurements of topological insulators are dominated by the conductivity of the bulk, leading to substantial difficulties in resolving the properties of the surface. To this end, we use high magnetic field, rf- and microwave-spectroscopy to selectively couple to the surface conductivity of Bi2Se3 at high frequency. In the frequency range of a few GHz we observe a crossover from quantum oscillations indicative of a small 3D Fermi surface, to cyclotron resonance indicative of a 2D surface state. By probing the conductivity at reduced skin depths, we have observed a 2D cyclotron resonance from a material whose bulk Fermi-surface is 3D. The frequency-magnetic field scaling of this resonance is inconsistent with the bulk effective mass, but more consistent with the dispersion and band filling of a Dirac-like surface state as observed by ARPES, with substantial manybody renormalization.

  18. Ultrafast Optical Excitation of a Persistent Surface-State Population in the Topological Insulator Bi2Se3

    SciTech Connect (OSTI)

    Sobota, Jonathan

    2012-03-14T23:59:59.000Z

    Using femtosecond time- and angle-resolved photoemission spectroscopy, we investigated the nonequilibrium dynamics of the topological insulator Bi{sub 2}Se{sub 3}. We studied p-type Bi{sub 2}Se{sub 3}, in which the metallic Dirac surface state and bulk conduction bands are unoccupied. Optical excitation leads to a meta-stable population at the bulk conduction band edge, which feeds a nonequilibrium population of the surface state persisting for >10 ps. This unusually long-lived population of a metallic Dirac surface state with spin texture may present a channel in which to drive transient spin-polarized currents.

  19. Photoemission Spectroscopy of Magnetic and Nonmagnetic Impurities on the Surface of the Bi2Se3 Topological Insulator

    E-Print Network [OSTI]

    Ohta, Shigemi

    Topological Insulator T. Valla,1,* Z.-H. Pan,1 D. Gardner,2 Y. S. Lee,2 and S. Chu3 1 Condensed Matter Physics; published 12 March 2012) Dirac-like surface states on surfaces of topological insulators have a chiral spin impurities on the surface of Bi2Se3, a model topological insulator. We reveal a remarkable insensitivity

  20. PHYSICAL REVIEW B 83, 165440 (2011) Electron interaction-driven insulating ground state in Bi2Se3 topological insulators

    E-Print Network [OSTI]

    Wang, Wei Hua

    2011-01-01T23:59:59.000Z

    topological insulators in the two-dimensional limit Minhao Liu,1 Cui-Zu Chang,1,2 Zuocheng Zhang,1 Yi Zhang,2 of ultrathin Bi2Se3 topological insulators with thickness from one quintuple layer to six quintuple layers that this unusual insulating ground state in the two-dimensional limit of topological insulators is induced

  1. Temperature dependent Raman scattering studies of three dimensional topological insulators Bi{sub 2}Se{sub 3}

    SciTech Connect (OSTI)

    Irfan, Bushra; Chatterjee, Ratnamala, E-mail: rmala@physics.iitd.ac.in [Department of Physics, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India); Sahoo, Satyaprakash; Gaur, Anand P. S.; Ahmadi, Majid; Katiyar, Ram S. [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931 (United States); Guinel, Maxime J.-F. [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931 (United States); Department of Chemistry, College of Natural Sciences, University of Puerto Rico, P.O. Box 70377, San Juan, Puerto Rico 00936-8377 (United States)

    2014-05-07T23:59:59.000Z

    We investigate the temperature dependent (83?K?T?523?K) frequency shift of 2A{sub g}{sup 1} and 1E{sub g}{sup 2} phonon modes in the three dimensional topological insulator Bi{sub 2}Se{sub 3}, using Raman spectroscopy. The high quality single crystals of Bi{sub 2}Se{sub 3} were grown using a modified Bridgman technique and characterized by Laue diffraction and high resolution transmission electron microscopy. A significant broadening in the line shape and red-shift in the frequencies were observed with increase in temperature. Polarized Raman scattering measurement shows a strong polarization effect of A{sub g}{sup 1} and A{sub g}{sup 2} phonon modes which confirms the good quality single crystals of Bi{sub 2}Se{sub 3}. Temperature co-efficient for A{sub 1g}{sup 1},?E{sub g}{sup 2}, and A{sub 1g}{sup 2} modes was estimated to be ?1.44?×?10{sup ?2}, ?1.94?×?10{sup ?2}, and ?1.95?×?10{sup ?2}?cm{sup ?1}?K, respectively. Our results shed light on anharmonic properties of Bi{sub 2}Se{sub 3}.

  2. Interface Driven Energy Filtering of Thermoelectric Power in Spark Plasma Sintered Bi2Te2.7Se0.3 Nanoplatelet Composites

    E-Print Network [OSTI]

    Xiong, Qihua

    Interface Driven Energy Filtering of Thermoelectric Power in Spark Plasma Sintered Bi2Te2.7Se0 of the thermodynamic environment during spark plasma sintering (SPS) on the TE performance of bulk figure of merit, Bi2Te2.7Se0.3 nanoplatelet composites, spark plasma sintering, interfaces, grain

  3. Structural properties of Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3} topological insulators grown by molecular beam epitaxy on GaAs(001) substrates

    SciTech Connect (OSTI)

    Liu, X.; Leiner, J.; Dobrowolska, M.; Furdyna, J. K. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Smith, D. J. [Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States); Fan, J. [Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States); Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287 (United States); Zhang, Y.-H. [Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287 (United States); School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States); Cao, H.; Chen, Y. P. [Department of Physics, Purdue University, West Lafayette, Indiana 47907 (United States); Kirby, B. J. [Center for Neutron Research, NIST, Gaithersburg, Maryland 20899 (United States)

    2011-10-24T23:59:59.000Z

    Thin films of Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3} have been grown on deoxidized GaAs(001) substrates using molecular beam epitaxy. Cross-sectional transmission electron microscopy established the highly parallel nature of the Te(Se)-Bi-Te(Se)-Bi-Te(Se) quintuple layers deposited on the slightly wavy GaAs substrate surface and the different crystal symmetries of the two materials. Raman mapping confirmed the presence of the strong characteristic peaks reported previously for these materials in bulk form. The overall quality of these films reveals the potential of combining topological insulators with ferromagnetic semiconductors for future applications.

  4. Electronic Structure of the Topological Insulator Bi[subscript 2]Se[subscript 3] Using Angle-Resolved Photoemission Spectroscopy: Evidence for a Nearly Full Surface Spin Polarization

    E-Print Network [OSTI]

    Pan, Z.-H.

    We performed high-resolution spin- and angle-resolved photoemission spectroscopy studies of the electronic structure and the spin texture on the surface of Bi[subscript 2]Se[subscript 3], a model TI. By tuning the photon ...

  5. Conductance modulation in topological insulator Bi{sub 2}Se{sub 3} thin films with ionic liquid gating

    SciTech Connect (OSTI)

    Son, Jaesung; Banerjee, Karan; Yang, Hyunsoo, E-mail: eleyang@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore)] [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore); Brahlek, Matthew; Koirala, Nikesh; Oh, Seongshik [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854 (United States)] [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854 (United States); Lee, Seoung-Ki [School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of) [School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); School of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Ahn, Jong-Hyun [School of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)] [School of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2013-11-18T23:59:59.000Z

    A Bi{sub 2}Se{sub 3} topological insulator field effect transistor is investigated by using ionic liquid as an electric double layer gating material, leading to a conductance modulation of 365% at room temperature. We discuss the role of charged impurities on the transport properties. The conductance modulation with gate bias is due to a change in the carrier concentration, whereas the temperature dependent conductance change is originated from a change in mobility. Large conductance modulation at room temperature along with the transparent optical properties makes topological insulators as an interesting (opto)electronic material.

  6. Effect of sintering in ball-milled K{sub 2}Bi{sub 8}Se{sub 13} thermoelectric nano-composites

    SciTech Connect (OSTI)

    Hatzikraniotis, E. [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)] [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Ioannou, M. [Department of Mechanical and Manufacturing Engineering, University of Cyprus, 1678 Nicosia (Cyprus)] [Department of Mechanical and Manufacturing Engineering, University of Cyprus, 1678 Nicosia (Cyprus); Chrissafis, K. [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)] [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Chung, D.Y. [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States)] [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Paraskevopoulos, K.M. [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)] [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Kyratsi, Th., E-mail: kyratsi@ucy.ac.cy [Department of Mechanical and Manufacturing Engineering, University of Cyprus, 1678 Nicosia (Cyprus)

    2012-09-15T23:59:59.000Z

    K{sub 2}Bi{sub 8}Se{sub 13} has many attractive features for thermoelectric applications. Recently, K{sub 2}Bi{sub 8}Se{sub 13}-based nanocomposite materials, consisting of nano-crystalline, micro-crystalline and amorphous phases, have been fabricated based on powder technology techniques. The Seebeck coefficient has been enhanced while the thermal conductivity has been decreased presenting, thus, interesting behavior. The behavior of the materials under heat treatment conditions is now of interest, as the application of sintering process is necessary for the development of thermoelectric modules. In this work, the crystallization of the K{sub 2}Bi{sub 8}Se{sub 13}-based nano-composites is studied using Differential Scanning Calorimetry. The results show that crystallization follows a multiple-step process with different activation energies. The thermoelectric properties are also discussed in the range that crystallization occurs. - Graphical Abstract: {beta}-K{sub 2}Bi{sub 8}Se{sub 13}-based nanocomposites follow a multiple-step crystallization process. Highlights: Black-Right-Pointing-Pointer K{sub 2}Bi{sub 8}Se{sub 13}-based composites consisting of nanocrystalline and amorphous phases. Black-Right-Pointing-Pointer Sintering results multiple-step crystallization with variable activation energies. Black-Right-Pointing-Pointer Thermoelectric properties follow a step-like behavior during sintering. Black-Right-Pointing-Pointer Properties are attributed to the strain relaxation, nucleation and grain growth.

  7. Electron-phonon superconductivity in LaO{sub 0.5}F{sub 0.5}BiSe{sub 2}

    SciTech Connect (OSTI)

    Feng, Yanqing; Du, Yongping; Wan, Xiangang, E-mail: xgwan@nju.edu.cn; Wang, Bogen [Department of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Ding, Hang-Chen [Key Laboratory of Polar Materials and Devices, Ministry of Education, East China Normal University, Shanghai 200062 (China); Savrasov, Sergey Y. [Department of Physics, University of California, Davis, One Shields Avenue, Davis, California 95616 (United States); Duan, Chun-Gang [Key Laboratory of Polar Materials and Devices, Ministry of Education, East China Normal University, Shanghai 200062 (China); National Laboratory for Infrared Physics, Chinese Academy of Sciences, Shanghai 200083 (China)

    2014-06-21T23:59:59.000Z

    We report density functional calculations of the electronic structure, Fermi surface, phonon spectrum and electron–phonon coupling for the newly discovered superconductor LaO{sub 0.5}F{sub 0.5}BiSe{sub 2}. It is confirmed that there is a strong Fermi surface nesting at (?,?,0), which results in unstable phonon branches. Combining the frozen phonon total energy calculations and an anharmonic oscillator model, we find that the quantum fluctuation prevents the appearance of static long–range order. The calculation shows that LaO{sub 0.5}F{sub 0.5}BiSe{sub 2} is highly anisotropic, and same as its cousin LaO{sub 0.5}F{sub 0.5}BiS{sub 2}, this compound is also a conventional electron-phonon coupling induced superconductor.

  8. Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2}: A new bismuth oxo-selenite bromide

    SciTech Connect (OSTI)

    Berdonosov, Peter S., E-mail: berdonosov@inorg.chem.msu.ru [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Olenev, Andrei V. [SineTheta Ltd., MSU Building 1-77, 119991 Moscow (Russian Federation)] [SineTheta Ltd., MSU Building 1-77, 119991 Moscow (Russian Federation); Kirsanova, Maria A. [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation)] [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Lebed, Julia B. [Institute for nuclear research RAS, 142190, Troitsk, Moscow region (Russian Federation)] [Institute for nuclear research RAS, 142190, Troitsk, Moscow region (Russian Federation); Dolgikh, Valery A. [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation)] [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation)

    2012-12-15T23:59:59.000Z

    A new bismuth oxo-selenite bromide Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2} was synthesized and structurally characterized. The crystal structure belongs to the triclinic system (space group P1-bar , Z=2, a=7.1253(7) A, b=10.972(1) A, c=12.117(1) A, {alpha}=67.765(7) Degree-Sign , {beta}=82.188(8) Degree-Sign , {gamma}=78.445(7) Degree-Sign ) and is unrelated to those of other known oxo-selenite halides. It can be considered as an open framework composed of BiO{sub x} or BiO{sub y}Br{sub z} polyhedrons forming channels running along [1 0 0] direction which contain the selenium atoms in pyramidal shape oxygen coordination (SeO{sub 3}E). The spectroscopic properties and thermal stability were studied. The new compound is stable up to 400 Degree-Sign C. - graphical abstract: New bismuth oxo-selenite bromide with new open framework structure. Highlights: Black-Right-Pointing-Pointer New bismuth oxo-selenite bromide was found and structurally characterized. Black-Right-Pointing-Pointer Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2} exhibit a new open framework structure type. Black-Right-Pointing-Pointer BiO{sub x} or BiO{sub y}Br{sub z} polyhedrons form channels in the structure which are decorated by [SeO{sub 3}E] groups.

  9. Discovery of a Topological Insulator Bi2Se3 with a Single Surface Dirac Cone. (DMR-0819860) IRG-A: M. Z. Hasan and R. J. Cava

    E-Print Network [OSTI]

    Petta, Jason

    Discovery of a Topological Insulator Bi2Se3 with a Single Surface Dirac Cone. (DMR-0819860) IRG field is applied. Recent research has uncovered a new class of insulators, called topological insulators spectroscopy (ARPES). In a new breakthrough, Hasan and Cava have now identified a second Topological Insulator

  10. PHYSICAL REVIEW B 88, 024515 (2013) Absence of zero-energy surface bound states in CuxBi2Se3 studied

    E-Print Network [OSTI]

    Peng, Haibing

    2013-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 88, 024515 (2013) Absence of zero-energy surface bound states in CuxBi2Se3 by an odd-parity full bulk superconducting gap and zero-energy surface Andreev bound states (Majorana fermions). A predicted consequence of such Majorana fermions is a peak in the zero-energy density of states

  11. Theoretical study of influencing factors on the dispersion of bulk band-gap edges and the surface states in topological insulators Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3}

    SciTech Connect (OSTI)

    Rusinov, I. P., E-mail: rusinovip@gmail.com; Nechaev, I. A. [Tomsk State University (Russian Federation); Chulkov, E. V. [Donostia International Physics Center (DIPC) (Spain)

    2013-06-15T23:59:59.000Z

    The dispersion of the band-gap edge states in bulk topological insulators Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3} is considered within density functional theory. The dependences of this dispersion both on the approximation used for an exchange-correlation functional at fixed unit cell parameters and atomic positions and on these parameters and positions that are obtained upon structural relaxation performed using a certain approximated functional are analyzed. The relative position of the Dirac point of topologically protected surface states and the valence band maximum in the surface electronic structure of the topological insulators is discussed.

  12. Anomalous reduction of the switching voltage of Bi-doped Ge{sub 0.5}Se{sub 0.5} ovonic threshold switching devices

    SciTech Connect (OSTI)

    Seo, Juhee [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 305-350 (Korea, Republic of); Ahn, Hyung-Woo [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Material Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Shin, Sang-yeol [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Materials Science and Engineering, Korea Aerospace University, Goyang 412-791 (Korea, Republic of); Cheong, Byung-ki; Lee, Suyoun, E-mail: slee-eels@kist.re.kr [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of)

    2014-04-14T23:59:59.000Z

    Switching devices based on Ovonic Threshold Switching (OTS) have been considered as a solution to overcoming limitations of Si-based electronic devices, but the reduction of switching voltage is a major challenge. Here, we investigated the effect of Bi-doping in Ge{sub 0.5}Se{sub 0.5} thin films on their thermal, optical, electrical properties, as well as on the characteristics of OTS devices. As Bi increased, it was found that both of the optical energy gap (E{sub g}{sup opt}) and the depth of trap states decreased resulting in a drastic reduction of the threshold voltage (V{sub th}) by over 50%. In addition, E{sub g}{sup opt} was found to be about three times of the conduction activation energy for each composition. These results are explained in terms of the Mott delocalization effect by doping Bi.

  13. Electronic Structure of the Topological Insulator Bi2Se3 Using Angle-Resolved Photoemission Spectroscopy: Evidence for a Nearly Full Surface Spin Polarization

    SciTech Connect (OSTI)

    Pan, Z.H.; Vescovo, E.; Fedorov, A.V.; Gardner, D.; Lee, Y.S.; Chu, S.; Gu, G.D.; Valla, T.

    2011-06-22T23:59:59.000Z

    We performed high-resolution spin- and angle-resolved photoemission spectroscopy studies of the electronic structure and the spin texture on the surface of Bi{sub 2}Se{sub 3}, a model TI. By tuning the photon energy, we found that the topological surface state is well separated from the bulk states in the vicinity of k{sub z} = Z plane of the bulk Brillouin zone. The spin-resolved measurements in that region indicate a very high degree of spin polarization of the surface state, {approx}0.75, much higher than previously reported. Our results demonstrate that the topological surface state on Bi{sub 2}Se{sub 3} is highly spin polarized and that the dominant factors limiting the polarization are mainly extrinsic.

  14. Comparison of crystal growth and thermoelectric properties of n-type Bi-Se-Te and p-type Bi-Sb-Te nanocrystalline thin films: Effects of homogeneous irradiation with an electron beam

    SciTech Connect (OSTI)

    Takashiri, Masayuki, E-mail: takashiri@tokai-u.jp; Imai, Kazuo; Uyama, Masato; Nishi, Yoshitake [Department of Materials Science, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan); Hagino, Harutoshi; Miyazaki, Koji [Department of Mechanical and Control Engineering, Kyushu Institute of Technology, 1-1 Sensui, Tobata-ku, Kitakyushu 804-8550 (Japan); Tanaka, Saburo [Department of Mechanical Engineering, College of Engineering, Nihon University, Nakagawara, Tokusada, Tamuramachi, Koriyama, Fukushima 963-8642 (Japan)

    2014-06-07T23:59:59.000Z

    The effects of homogenous electron beam (EB) irradiation on the crystal growth and thermoelectric properties of n-type Bi-Se-Te and p-type Bi-Sb-Te thin films were investigated. Both types of thin films were prepared by flash evaporation, after which homogeneous EB irradiation was performed at an acceleration voltage of 0.17?MeV. For the n-type thin films, nanodots with a diameter of less than 10?nm were observed on the surface of rice-like nanostructures, and crystallization and crystal orientation were improved by EB irradiation. The resulting enhancement of mobility led to increased electrical conductivity and thermoelectric power factor for the n-type thin films. In contrast, the crystallization and crystal orientation of the p-type thin films were not influenced by EB irradiation. The carrier concentration increased and mobility decreased with increased EB irradiation dose, possibly because of the generation of defects. As a result, the thermoelectric power factor of p-type thin films was not improved by EB irradiation. The different crystallization behavior of the n-type and p-type thin films is attributed to atomic rearrangement during EB irradiation. Selenium in the n-type thin films is more likely to undergo atomic rearrangement than the other atoms present, so only the crystallinity of the n-type Bi-Se-Te thin films was enhanced.

  15. Studies on the Bi[subscript 2]Te[subscript 3]–Bi[subscript 2]Se[subscript 3]–Bi[subscript 2]S[subscript 3] system for mid-temperature thermoelectric energy conversion

    E-Print Network [OSTI]

    Liu, Weishu

    Bismuth telluride (Bi[subscript 2]Te[subscript 3]) and its alloys have been widely investigated as thermoelectric materials for cooling applications at around room temperature. We report a systematic study on many compounds ...

  16. Thermoelectric properties of n-type Bi{sub 2}(Te{sub 1{minus}x}Se{sub x}){sub 3} fabricated by mechanical alloying and hot pressing

    SciTech Connect (OSTI)

    Kim, H.J.; Choi, J.S.; Oh, T.S.; Hyun, D.B.

    1997-07-01T23:59:59.000Z

    Thermoelectric properties of polycrystalline Bi{sub 2}(Te{sub 1{minus}x}Se{sub x}){sub 3} (0.05 {le} x {le} 0.25), fabricated by mechanical alloying and hot pressing, have been investigated. Formation of n-type Bi{sub 2}(Te{sub 0.9}Se{sub 0.1}){sub 3} alloy powders was completed by mechanical alloying for 3 hours at ball-to-material ratio of 5:1, and processing time for Bi{sub 2}(Te{sub 1{minus}x}Se{sub x}){sub 3} formation increased with Bi{sub 2}Se{sub 3} content x. Figure-of-merit of Bi{sub 2}(Te{sub 0.9}Se{sub 0.1}) was markedly increased by hot pressing at temperatures above 450 C, and maximum value of 1.9 x 10{sup {minus}3}/K was obtained by hot pressing at 550 C. With addition of 0.015 wt% Bi as acceptor dopant, figure-of-merit of Bi{sub 2}(Te{sub 0.9}Se{sub 0.1}){sub 3} was hot pressed at 550 C, could be improved to 2.1 x 10{sup {minus}3}/K. When Bi{sub 2}(Te{sub 1{minus}x}Se{sub x}){sub 3} was hot pressed at 550 C, figure-of-merit increased from 1.14 x 10{sup {minus}3}/K to 1.92 x 10{sup {minus}3}/K with increasing Bi{sub 2}Se{sub 3} content x from 0.05 to 0.15, and then decreased to 1.30 x 10{sup {minus}3}/K for x = 0.25 composition.

  17. Effect of carrier recombination on ultrafast carrier dynamics in thin films of the topological insulator Bi{sub 2}Se{sub 3}

    SciTech Connect (OSTI)

    Glinka, Yuri D., E-mail: ydglinka@mail.wvu.edu [Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506-6315 (United States); Institute of Physics, National Academy of Sciences of Ukraine, Kiev 03028 (Ukraine); Babakiray, Sercan; Johnson, Trent A.; Holcomb, Mikel B.; Lederman, David [Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506-6315 (United States)

    2014-10-27T23:59:59.000Z

    Transient reflectivity (TR) from thin films (6–40?nm thick) of the topological insulator Bi{sub 2}Se{sub 3} revealed ultrafast carrier dynamics, which suggest the existence of both radiative and non-radiative recombination between electrons residing in the upper cone of initially unoccupied high energy Dirac surface states (SS) and holes residing in the lower cone of occupied low energy Dirac SS. The modeling of measured TR traces allowed us to conclude that recombination is induced by the depletion of bulk electrons in films below ?20?nm thick due to the charge captured on the surface defects. We predict that such recombination processes can be observed using time-resolved photoluminescence techniques.

  18. Anomalous transport in an n-type topological insulator ultrathin Bi2Se3 film Toru Hirahara,1,* Yusuke Sakamoto,1 Yasuo Takeichi,2 Hidetoshi Miyazaki,3 Shin-ichi Kimura,3 Iwao Matsuda,2

    E-Print Network [OSTI]

    Hasegawa, Shuji

    Anomalous transport in an n-type topological insulator ultrathin Bi2Se3 film Toru Hirahara,1, 73.61.Ng I. INTRODUCTION Topological insulators have attracted much attention from a wide variety, they are mathematically characterized by the so-called Z2 topological number.1 While the bulk is insulating

  19. Structural, electrical, and thermoelectrical properties of (Bi{sub 1-x}Sb{sub x}){sub 2}Se{sub 3} alloys prepared by a conventional melting technique

    SciTech Connect (OSTI)

    Shokr, E. Kh.; Ibrahim, E. M. M., E-mail: e.ibrahim@science.sohag.edu.eg; Abdel Hakeem, A. M.; Adam, A. M. [Sohag University, Physics Department, Faculty of Science (Egypt)] [Sohag University, Physics Department, Faculty of Science (Egypt)

    2013-01-15T23:59:59.000Z

    Polycrystalline solid solutions of (Bi{sub 1-x}Sb{sub x}){sub 2}Se{sub 3} (x = 0, 0.025, 0.050, 0.075, 0.100) were prepared using a facile method based on the conventional melting technique followed by annealing process. X-ray analysis and Raman spectroscopical measurements revealed formation of Bi{sub 2}Se{sub 3} in single phase. The electrical and thermoelectric properties have been studied on the bulk samples in the temperature range 100-420 K. The electrical conductivity measurements show that the activation energy and room-temperature electrical conductivity dependences on the Sb content respectively exhibit minimum and maximum values at x = 0.05. The thermoelectric power exhibited a maximum value near the room temperature suggesting promising materials for room-temperature applications. The highest power factor value was found to be 13.53 {mu}W K{sup -2} cm{sup -1} and recorded for the x = 0.05 compound.

  20. Microstructural and thermoelectric properties of p-type Te-doped Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} and n-type SbI{sub 3}-doped Bi{sub 2}Te{sub 2.85}Se{sub 0.15} compounds

    SciTech Connect (OSTI)

    Seo, J.; Park, K.; Lee, C.; Kim, J.

    1997-07-01T23:59:59.000Z

    The p-type Te-doped Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} and n-type SbI{sub 3}-doped Bi{sub 2}Te{sub 2.85}Se{sub 0.15} thermoelectric compounds were fabricated by hot pressing in the temperature range of 380 to 440 C under 200 MPa in Ar. Both the compounds were highly dense and showed high crystalline quality. The grains of the compounds were preferentially oriented and contained many dislocations through the hot pressing. The fracture path followed the transgranular cleavage planes, which are perpendicular to the c-axis. In addition, with increasing the pressing temperature, the figure of merit was increased. The highest values of figure of merit for the p- and n-type compounds, which were obtained at 420 C, were 2.69 x 10{sup {minus}3}/K and 2.35 x 10{sup {minus}3}/K, respectively.

  1. Superconductivity in the topological Insulator Bi2Se3 (DMR 0819860) IRG-A : Y. S. Hor, A. J. Williams, J. G. Checkelsky, P. Roushan, J. Seo, Q. Xu, H.W. Zandbergen, A. Yazdani, N. P. Ong, and R. J. Cava

    E-Print Network [OSTI]

    Petta, Jason

    Superconductivity in the topological Insulator Bi2Se3 (DMR 0819860) IRG-A : Y. S. Hor, A. J a novel class of insulators, called topological insulators, in which current can flow on the surface. Researchers at PCCM have taken a big step in this direction (1,2). They showed that the topological insulator

  2. Understanding of the contact of nanostructured thermoelectric n-type Bi[subscript 2]Te[subscript 2.7]Se[subscript 0.3] legs for power generation applications

    E-Print Network [OSTI]

    Liu, Weishu

    Traditional processes of making contacts (metallization layer) onto bulk crystalline Bi2Te3-based materials do not work for nanostructured thermoelectric materials either because of weak bonding strength or an unstable ...

  3. Bi-2212 and Bi-2223 wire development

    SciTech Connect (OSTI)

    Willis, J.O.; Ray, R.D. II; Holesinger, T.G. [and others

    1995-12-01T23:59:59.000Z

    The results of innovative processing of Bi-2212 by isothermal melt processing and by controlled oxygen pressure cooling yield improved properties over the conventional routes. The addition of large grains of Ag has resulted in improved core/interface geometry and better performance in Bi-2212 and Bi-2223. A deformation processing study of Bi-2223 showed the effects of sheath material, relative core thickness, and reduction per pass on core/interface uniformity.

  4. Signatures of charge inhomogeneities in the infrared spectra of topological insulators Bi This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Dordevic, Sasha V.

    Signatures of charge inhomogeneities in the infrared spectra of topological insulators Bi 2 Se 3.1088/0953-8984/25/7/075501 Signatures of charge inhomogeneities in the infrared spectra of topological insulators Bi2Se3, Bi2Te3 and Sb2/075501 Abstract We present the results of an infrared spectroscopy study of topological insulators Bi2Se3, Bi2Te3

  5. A study of a procedure for editing data

    E-Print Network [OSTI]

    Smith, David Worth

    1970-01-01T23:59:59.000Z

    . 11vciltol les ciirsory erlaniination of the eight items listed iibove shows iio obvi o?s basis for a se!. of intevn il collsl. st. e?cy cciuntlofls Hei(ever i I, hc ( el'lsus Bul cau hus !o:ig recognized that ccvtain vatios of report avc... of seve& aI & epovt. vari &bi es, e. g. ?un&her of &uupI oyces on Ocl. obev 1, co& n acveage, o&?umbev of children. A &Ll&?&inta set is & e&ul ?'&to the program ?hich caus&. "s various operations to be performed on the & ?dividual report vari...

  6. BI\it-ĂŻ-?

    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 NazimBudgetRenewable8/07/13 PageBI\it-ĂŻ-?

  7. Incoherent Bi off-centering in Bi?Ti?O?O' and Bi?Ru?O?O': Insulator versus metal

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

    Shoemaker, Daniel P.; Seshadri, Ram; Tachibana, Makoto; Hector, Andrew L.

    2011-08-01T23:59:59.000Z

    In the cubic, stoichiometric oxide compounds Bi?Ti?O?O' (also written as Bi?Ti?O?) and Bi?Ru?O?O' (also written as Bi?Ru?O?) Bił? ions on the pyrochlore A site display a propensity to off-center. Unlike Bi?Ti?O?O', Bi?Ru?O?O' is a metal, so it is of interest to ask whether conduction electrons and/or involvement of Bi 6s states at the Fermi energy influence Bił? displacements. The Bił? off-centering in Bi?Ti?O?O' has previously been revealed to be incoherent from detailed reverse Monte Carlo analysis of total neutron scattering. Similar analysis of Bi?Ru?O?O' reveals incoherent off-centering as well, but of smaller magnitude and with distinctly different orientational preference. Analysis of the distributions of metal to oxygen distances presented suggests that Bi in both compounds is entirely Bił?. Disorder in Bi?Ti?O?O' has the effect of stabilizing valence while simultaneously satisfying the steric constraint imposed by the presence of the lone pair of electrons. In Bi?Ru?O?O', off-centering is not required to satisfy valence and seems to be driven by the lone pair. Decreased volume of the lone pair may be a result of partial screening by conduction electrons.

  8. Incoherent Bi off-centering in Bi?Ti?O?O' and Bi?Ru?O?O': Insulator versus metal

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

    Shoemaker, Daniel P.; Seshadri, Ram; Tachibana, Makoto; Hector, Andrew L.

    2011-08-01T23:59:59.000Z

    In the cubic, stoichiometric oxide compounds Bi?Ti?O?O' (also written as Bi?Ti?O?) and Bi?Ru?O?O' (also written as Bi?Ru?O?) Bił? ions on the pyrochlore A site display a propensity to off-center. Unlike Bi?Ti?O?O', Bi?Ru?O?O' is a metal, so it is of interest to ask whether conduction electrons and/or involvement of Bi 6s states at the Fermi energy influence Bił? displacements. The Bił? off-centering in Bi?Ti?O?O' has previously been revealed to be incoherent from detailed reverse Monte Carlo analysis of total neutron scattering. Similar analysis of Bi?Ru?O?O' reveals incoherent off-centering as well, but of smaller magnitude and with distinctly different orientational preference. Analysismore »of the distributions of metal to oxygen distances presented suggests that Bi in both compounds is entirely Bił?. Disorder in Bi?Ti?O?O' has the effect of stabilizing valence while simultaneously satisfying the steric constraint imposed by the presence of the lone pair of electrons. In Bi?Ru?O?O', off-centering is not required to satisfy valence and seems to be driven by the lone pair. Decreased volume of the lone pair may be a result of partial screening by conduction electrons.« less

  9. Titanium alkoxide induced BiOBrBi2WO6 mesoporous nanosheet composites with much enhanced

    E-Print Network [OSTI]

    Cao, Guozhong

    Titanium alkoxide induced BiOBr­Bi2WO6 mesoporous nanosheet composites with much enhanced for the preparation of BiOBr­Bi2WO6 mesoporous nanosheet composites (MNCs) in the presence of titanium isopropoxide, Ti(Oi Pr)4. High resolution transmission electron microscopy, X-ray diffraction, nitrogen adsorption

  10. Analytic equivalence relations and bi-embeddability

    E-Print Network [OSTI]

    Ros, Luca Motto

    Analytic equivalence relations and bi-embeddability Luca Motto Ros Kurt G¨odel Research Center Analytic equivalence relations and bi-embeddability #12;Analytic equivalence relations A subset of a Polish Analytic equivalence relations and bi-embeddability #12;Analytic equivalence relations A subset of a Polish

  11. De de se

    E-Print Network [OSTI]

    Anand, Pranav

    2006-01-01T23:59:59.000Z

    In this dissertation, I argue against a unitary treatment of individual de se ascription. Based on consideration of Yoruba logophors and English dream-report pronouns, I show that one mechanism is best analyzed as binding ...

  12. Superconductivity in textured Bi clusters/Bi{sub 2}Te{sub 3} films

    SciTech Connect (OSTI)

    Le, Phuoc Huu [Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 30049, Taiwan (China); Faculty of Basic Sciences, Can Tho University of Medicine and Pharmacy, 179 Nguyen Van Cu Street, Can Tho (Viet Nam); Tzeng, Wen-Yen; Chen, Hsueh-Ju; Luo, Chih Wei, E-mail: cwluo@mail.nctu.edu.tw [Department of Electrophysics, National Chiao Tung University, Hsinchu 300, Taiwan (China); Lin, Jiunn-Yuan [Institute of Physics, National Chiao Tung University, Hsinchu 300, Taiwan (China); Leu, Jihperng, E-mail: jimleu@mail.nctu.edu.tw [Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 30049, Taiwan (China)

    2014-09-01T23:59:59.000Z

    We report superconductivity at an onset critical temperature below 3.1 K in topological insulator ?200-nm-thick Bi{sub 2}Te{sub 3} thin films grown by pulsed laser deposition. Using energy-dispersive X-ray spectroscopy elemental mapping and Auger electron spectroscopy elemental depth profiling, we clearly identified bismuth (Bi) precipitation and Bi cluster signatures. Superconductivity in the Bi{sub 2}Te{sub 3} films was attributed to the proximity effect of Bi clusters precipitated on the surface of the Bi{sub 2}Te{sub 3} films.

  13. Highly Reversible Mg Insertion in Nanostructured Bi for Mg Ion...

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

    Reversible Mg Insertion in Nanostructured Bi for Mg Ion Batteries. Highly Reversible Mg Insertion in Nanostructured Bi for Mg Ion Batteries. Abstract: Rechargeable magnesium...

  14. Bi23 BIOLOGY TUTORIALS WINTER TERM 2014

    E-Print Network [OSTI]

    Low, Steven H.

    Bi23 BIOLOGY TUTORIALS WINTER TERM 2014 SECTIONS 1 ­ 3 The Function and Regulation of Sleep (3. Huang, x3446, MC 156-29 #12;Bi23 BIOLOGY TUTORIALS WINTER TERM 2014 SECTIONS 4-6 Physical Principles crystallography and neutron scattering; nuclear magnetic resonance and magnetic resonance imaging; peptide and DNA

  15. Electrical Transport of Topological Insulator-Bi2Se3 and Thermoelectric Properties of Graphene

    E-Print Network [OSTI]

    WEI, PENG

    2011-01-01T23:59:59.000Z

    68 4.1.2 Peltier effect………………………………………………………………………………..69for the measurement of the Peltier effect…………………………………….69= ? V/(T 1 – T 2 ). 4.1.2 Peltier effect: material A r q j T

  16. Electrical Transport of Topological Insulator-Bi2Se3 and Thermoelectric Properties of Graphene

    E-Print Network [OSTI]

    WEI, PENG

    2011-01-01T23:59:59.000Z

    oscillation features at different gate voltages………………………………oscillation features on the raw MR data at different gate voltages.oscillations probably correspond to the top surface, which should not be very sensitive to the gate voltage.

  17. Effects of Magnetic Doping on Weak Antilocalization in Narrow Bi2Se3 Nanoribbons

    E-Print Network [OSTI]

    Cui, Yi

    , Stanford University, Stanford, California 94305, United States Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States *S Supporting Information ABSTRACT: We report low-temperature, magnetotransport measurements

  18. Electrical Transport of Topological Insulator-Bi2Se3 and Thermoelectric Properties of Graphene

    E-Print Network [OSTI]

    WEI, PENG

    2011-01-01T23:59:59.000Z

    thermo-voltage to a step jump of the heater power is at theThe heater power is quickly raised up step by step for four

  19. Thermoelectric Potential of Bi and Bi1-x Sbx Nanowire M. S. Dresselhausa,b

    E-Print Network [OSTI]

    Cronin, Steve

    Thermoelectric Potential of Bi and Bi1-x Sbx Nanowire Arrays M. S. Dresselhausa,b , Y.-M. Lina , O for thermoelectric applications is discussed. The advantages of bismuth as a low dimensional thermoelectric material as the wire diameter as materials parameters for optimizing the thermoelectric performance of these nanowires

  20. Roanoke River Basin Bi-State Commission (Multiple States)

    Broader source: Energy.gov [DOE]

    The Roanoke River Basin Bi-State Commission was established as a bi-state commission composed of members from the Commonwealth of Virginia and the State of North Carolina. The purpose of the...

  1. High-Pressure Synthesis and Structure Determination of K6(SeO4)(SeO5), The First Potassium Orthoselenate(VI)

    SciTech Connect (OSTI)

    Orosel,D.; Dinnebeier, R.; Jansen, M.

    2006-01-01T23:59:59.000Z

    The authors report on the first synthesis of a potassium orthoselenate(VI), K{sub 6}(SeO{sub 4})(SeO{sub 5}), and the structure determination from synchrotron powder diffraction data. The title compound crystallizes in the tetragonal space group P4{sub 1}2{sub 1}2 with a = 8.1259(1) {angstrom}, c = 17.4953(2) {angstrom}, V = 1155.21(2) {angstrom}{sup 3}, and Z = 4. Selenium displays two different complex anions, tetrahedral SeO{sub 4}{sup 2-} and trigonal-bipyramidal SeO{sub 5}{sup 4-}. When the formula is reduced to A{sub 3}B, the spatial arrangement of the constituting building units can be derived from the Li{sub 3}Bi type of structure.

  2. CeBiTec Symposium Molecular Biotechnology

    E-Print Network [OSTI]

    Moeller, Ralf

    : Bacterial and Environmental Biotechnology Chair: Volker F. Wendisch 12:30 Jörn Kalinowski (Technology for biotechnological applications 14:30 Coffee and Cake / Poster Presentation Session II: Biopolymers Chair: Dirk9th CeBiTec Symposium Molecular Biotechnology Center for Interdisciplinary Research (Zi

  3. Systems and methods for bi-directional energy delivery with galvanic isolation

    DOE Patents [OSTI]

    Kajouke, Lateef A.

    2013-06-18T23:59:59.000Z

    Systems and methods are provided for bi-directional energy delivery. A charging system comprises a first bi-directional conversion module, a second bi-directional conversion module, and an isolation module coupled between the first bi-directional conversion module and the second bi-directional conversion module. The isolation module provides galvanic isolation between the first bi-directional conversion module and the second bi-directional conversion module.

  4. Metallurgy, thermal stability, and failure mode of the commercial Bi-Te-based thermoelectric modules.

    SciTech Connect (OSTI)

    Yang, Nancy Y. C.; Morales, Alfredo Martin

    2009-02-01T23:59:59.000Z

    Bi-Te-based thermoelectric (TE) alloys are excellent candidates for power generation modules. We are interested in reliable TE modules for long-term use at or below 200 C. It is known that the metallurgical characteristics of TE materials and of interconnect components affect the performance of TE modules. Thus, we have conducted an extensive scientific investigation of several commercial TE modules to determine whether they meet our technical requirements. Our main focus is on the metallurgy and thermal stability of (Bi,Sb){sup 2}(Te,Se){sup 3} TE compounds and of other materials used in TE modules in the temperature range between 25 C and 200 C. Our study confirms the material suite used in the construction of TE modules. The module consists of three major components: AlN cover plates; electrical interconnects; and the TE legs, P-doped (Bi{sub 8}Sb{sub 32})(Te{sub 60}) and N-doped (Bi{sub 37}Sb{sub 3})(Te{sub 56}Se{sub 4}). The interconnect assembly contains Sn (Sb {approx} 1wt%) solder, sandwiched between Cu conductor with Ni diffusion barriers on the outside. Potential failure modes of the TE modules in this temperature range were discovered and analyzed. The results show that the metallurgical characteristics of the alloys used in the P and N legs are stable up to 200 C. However, whole TE modules are thermally unstable at temperatures above 160 C, lower than the nominal melting point of the solder suggested by the manufacture. Two failure modes were observed when they were heated above 160 C: solder melting and flowing out of the interconnect assembly; and solder reacting with the TE leg, causing dimensional swelling of the TE legs. The reaction of the solder with the TE leg occurs as the lack of a nickel diffusion barrier on the side of the TE leg where the displaced solder and/or the preexisting solder beads is directly contact the TE material. This study concludes that the present TE modules are not suitable for long-term use at temperatures above 160 C due to the reactivity between the Sn-solder and the (Bi,Sb){sup 2}(Te,Se){sup 3} TE alloys. In order to deploy a reliable TE power generator for use at or below 200 C, alternate interconnect materials must be used and/or a modified module fabrication technique must be developed.

  5. Green route synthesis of high quality CdSe quantum dots for applications in light emitting devices

    SciTech Connect (OSTI)

    Bera, Susnata, E-mail: susnata.bera@gmail.com [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Singh, Shashi B. [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Ray, S.K., E-mail: physkr@phy.iitkgp.ernet.in [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2012-05-15T23:59:59.000Z

    Investigation was made on light emitting diodes fabricated using CdSe quantum dots. CdSe quantum dots were synthesized chemically using olive oil as the capping agent, instead of toxic phosphine. Room temperature photoluminescence investigation showed sharp 1st excitonic emission peak at 568 nm. Bi-layer organic/inorganic (P3HT/CdSe) hybrid light emitting devices were fabricated by solution process. The electroluminescence study showed low turn on voltage ({approx}2.2 V) .The EL peak intensity was found to increase by increasing the operating current. - Graphical abstract: Light emitting diode was fabricated using CdSe quantum dots using olive oil as the capping agent, instead of toxic phosphine. Bi-layer organic/inorganic (P3HT/CdSe) hybrid light emitting device shows strong electroluminescence in the range 630-661 nm. Highlights: Black-Right-Pointing-Pointer CdSe Quantum dots were synthesized using olive oil as the capping agent. Black-Right-Pointing-Pointer Light emitting device was fabricated using CdSe QDs/P3HT polymer heterojunction. Black-Right-Pointing-Pointer The I-V characteristics study showed low turn on voltage at {approx}2.2 V. Black-Right-Pointing-Pointer The EL peak intensity increases with increasing the operating current.

  6. Bi-Directional Fast Charging Study Report

    SciTech Connect (OSTI)

    Tyler Gray

    2012-02-01T23:59:59.000Z

    This report details the hardware and software infrastructure needed to demonstrate the possibility of utilizing battery power in plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EVs) with a bi directional fast charger to support/offset peak building loads. This document fulfills deliverable requirements for Tasks 1.2.1.2, 1.2.1.3, and 1.2.1.4 of Statement of Work (SOW) No.5799 for Electric Transportation Engineering Corporation, now ECOtality North America (NA) support for the Idaho National Laboratory (INL).

  7. Endoplasmic reticulum protein BI-1 regulates Ca2+

    E-Print Network [OSTI]

    Nizet, Victor

    Endoplasmic reticulum protein BI-1 regulates Ca2+ -mediated bioenergetics to promote autophagy by inositol triphosphate receptors (IP3Rs) maintains cellular bioenergetics, thus suppressing autophagy. We. By reducing steady-state levels of ER Ca2+ via IP3Rs, BI-1 influences mitochondrial bioenergetics, reducing

  8. Extreme solid state refrigeration using nanostructured Bi-Te alloys.

    SciTech Connect (OSTI)

    Lima Sharma, Ana L. (San Jose State University, San Jose, CA); Spataru, Dan Catalin; Medlin, Douglas L.; Sharma, Peter Anand; Morales, Alfredo Martin

    2009-09-01T23:59:59.000Z

    Materials are desperately needed for cryogenic solid state refrigeration. We have investigated nanostructured Bi-Te alloys for their potential use in Ettingshausen refrigeration to liquid nitrogen temperatures. These alloys form alternating layers of Bi{sub 2} and Bi{sub 2}Te{sub 3} blocks in equilibrium. The composition Bi{sub 4}Te{sub 3} was identified as having the greatest potential for having a high Ettingshausen figure of merit. Both single crystal and polycrystalline forms of this material were synthesized. After evaluating the Ettingshausen figure of merit for a large, high quality polycrystal, we simulated the limits of practical refrigeration in this material from 200 to 77 K using a simple device model. The band structure was also computed and compared to experiments. We discuss the crystal growth, transport physics, and practical refrigeration potential of Bi-Te alloys.

  9. A CAD tool for the power estimation of CMOS, BiCMOS and BiNMOS gates

    E-Print Network [OSTI]

    Islam, Kazi Inamul

    1995-01-01T23:59:59.000Z

    This thesis describes a CAD tool for the power estimation of CMOS, BiCMOS and BiNMOS gates. Using analytical models for the transient behavior of the gates, accurate estimates of the power dissipated by each type of gate during a typical transition...

  10. Comparison of growth texture in round Bi2212 and flat Bi2223 wires and its relation to high critical current density development

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

    Kametani, F.; Jiang, J.; Matras, M.; Abraimov, D.; Hellstrom, E. E.; Larbalestier, D. C.

    2015-02-10T23:59:59.000Z

    Why Bi?Sr?CaCu?Ox (Bi2212) allows high critical current density Jc in round wires rather than only in the anisotropic tape form demanded by all other high temperature superconductors is important for future magnet applications. Here we compare the local texture of state-of-the-art Bi2212 and Bi2223 ((Bi,Pb)?Sr?Ca?Cu?O??), finding that round wire Bi2212 generates a dominant a-axis growth texture that also enforces a local biaxial texture (FWHM more »perpendicular to the tape plane without any in-plane texture. Consistent with these observations, a marked, field-increasing, field-decreasing Jc(H) hysteresis characteristic of weak-linked systems appears in Bi2223 but is absent in Bi2212 round wire. Growth-induced texture on cooling from the melt step of the Bi2212 Jc optimization process appears to be the key step in generating this highly desirable microstructure.« less

  11. Bi-metric Gravity and "Dark Matter"

    E-Print Network [OSTI]

    I. T. Drummond

    2000-08-18T23:59:59.000Z

    We present a bi-metric theory of gravity containing a length scale of galactic size. For distances less than this scale the theory satisfies the standard tests of General Relativity. For distances greater than this scale the theory yields an effective gravitational constant much larger than the locally observed value of Newton's constant. The transition from one regime to the other through the galactic scale can explain the observed rotation curves of galaxies and hence the effects normally attributed to the presence of dark matter. Phenomena on an extragalactic scale such as galactic clusters and the expansion of the universe are controlled by the enhanced gravitational coupling. This provides an explanation of the missing matter normally invoked to account for the observed value of Hubble's constant in relation to observed matter.

  12. Thermal expansion coefficients of Bi2Se3 and Sb2Te3 crystals from 10 K to 270 K

    E-Print Network [OSTI]

    Chen, Yong P.

    Mexico 87185, USA 5 Sandia National Laboratories, Livermore, California 94550, USA (Received 12 September extensive stud- ies in 1950s and 1960s as excellent thermoelectric materials, some basic physical properties

  13. Ultrafast Optical Excitation of a Persistent Surface-State Population in the Topological Insulator Bi2Se3

    E-Print Network [OSTI]

    Fisher, Ian

    . Kirchmann,1,4,* and Z.-X. Shen1,2,3, 1 Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA 2 Geballe Laboratory [9,10] and optical measurements [11,12]. In this Letter we report time- and angle-resolved photo

  14. Anharmonic phonons and magnons in BiFeO3

    SciTech Connect (OSTI)

    Delaire, Olivier A [ORNL; Ma, Jie [ORNL; Stone, Matthew B [ORNL; Huq, Ashfia [ORNL; Gout, Delphine J [ORNL; Brown, Craig [National Institute of Standards and Technology (NIST); Wang, Kefeng [Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing; Ren, Zhifeng [Boston College, Chestnut Hill

    2012-01-01T23:59:59.000Z

    The phonon density of states (DOS) and magnetic excitation spectrum of polycrystalline BiFeO3 were measured for temperatures 200 < T < 750K , using inelastic neutron scattering (INS). Our results indicate that the magnetic spectrum of BiFeO3 closely resembles that of similar Fe perovskites, such as LaFeO3, despite the cycloid modulation in BiFeO3. We do not find any evidence for a spin gap. A strong T-dependence of the phonon DOS was found, with a marked broadening of the whole spectrum, providing evidence of strong anharmonicity. This anharmonicity is corroborated by large amplitude motions of Bi and O ions observed with neutron diffraction. These results highlight the importance of spin-phonon coupling in this material.

  15. 38 CHAPTER 1. ASSEMBLY MANUAL BiDirectional Motor

    E-Print Network [OSTI]

    38 CHAPTER 1. ASSEMBLY MANUAL Bi­Directional Motor and Infrared Beacon Uni­Directional Motor, LED, Incandescent Lamp Sensor, Polarized Sensor, Non­polarized Figure 1.26: Standard Connector Plug Configurations

  16. Thermal Stability of MnBi Magnetic Materials. | EMSL

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

    because Mn is easy to react with oxygen. MnO formation is irreversible and causes degradation to the magnetic properties. In this paper, we report our effort on developing MnBi...

  17. Melt processing of Bi--2212 superconductors using alumina

    DOE Patents [OSTI]

    Holesinger, Terry G. (Los Alamos, NM)

    1999-01-01T23:59:59.000Z

    Superconducting articles and a method of forming them, where the superconducting phase of an article is Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.y (Bi-2212). Alumina is combined with Bi-2212 powder or Bi-2212 precursor powder and, in order to form an intimate mixture, the mixture is melted and rapidly cooled to form a glassy solid. The glassy solid is comminuted and the resulting powder is combined with a carrier. An alternative to melting is to form the mixture of nanophase alumina and material having a particle size of less than about 10 microns. The powder, with the carrier, is melt processed to form a superconducting article.

  18. Microfluidics {sjauh, btzhang}@bi.snu.ac.kr

    E-Print Network [OSTI]

    Microfluidics {sjauh, btzhang}@bi.snu.ac.kr Solving Shortest Path Problems Using Microfluidics Sahng-Joon Auh and Byoung-Tak Zhang Biointelligence Lab, School of Computer Science and Engineering Seoul National University . microfluidics MEMS

  19. Electronic-Structure of the Semimetals Bi and Sb

    E-Print Network [OSTI]

    LIU, Y.; Allen, Roland E.

    1995-01-01T23:59:59.000Z

    characteris- tic length, which makes Sb and Bi ideal for studying and employing quantum confinement effects. The three above semimetal-semiconductor superlattices are all grown in the [111] direction, along which the electron efFective masses of Bi and Sb... are relatively small and the quantum confinement length (scaling as m' ') consequently large. Also, there is only a small lattice mismatch in each case between the (111) planes of semimetal and semiconduc- tor. ' These three systems are, therefore...

  20. SECOND HARMONIC GENERATION OF Bi4Ti3O12 FILMS IN-SITU PROBING OF DOMAIN POLING IN Bi4Ti3O12 THIN

    E-Print Network [OSTI]

    Gopalan, Venkatraman

    SECOND HARMONIC GENERATION OF Bi4Ti3O12 FILMS IN-SITU PROBING OF DOMAIN POLING IN Bi4Ti3O12 THIN FILMS BY OPTICAL SECOND HARMONIC GENERATION YANIV BARAD, VENKATRAMAN GOPALAN Materials Research, of a ferroelectric Bi4Ti3O12 thin film using optical second harmonic generation as a probe. The ferroelectric

  1. Photoluminescence and photocatalytic properties of BiOCl and Bi{sub 24}O{sub 31}Cl{sub 10} nanostructures synthesized by electrolytic corrosion of metal Bi

    SciTech Connect (OSTI)

    Chen, G., E-mail: gchen@mail.njust.edu.cn [Engineering Research Center of Materials Behavior and Design, Ministry of Education, Joint Laboratory of Nanostructured Materials and Technology, Nanjing University of Science and Technology, Nanjing 210094 (China); Fang, G.L.; Tang, G.D. [Engineering Research Center of Materials Behavior and Design, Ministry of Education, Joint Laboratory of Nanostructured Materials and Technology, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2013-03-15T23:59:59.000Z

    Highlights: ? We report a facile method to synthesize bismuth oxychlorides. ? The BiOCl nanosheets have both ultraviolet-blue emission zone and visible emission zone. ? The Bi{sub 24}O{sub 31}Cl{sub 10} nanostructure is a direct electron transition semiconductor. ? The broad and intensive UV emission were observed in Bi{sub 24}O{sub 31}Cl{sub 10} nanostructure. - Abstract: Nanostructured BiOCl and Bi{sub 24}O{sub 31}Cl{sub 10} have been synthesized by electrolytic corrosion of metal Bi. The photocatalysis and photoluminescence (PL) properties of BiOCl and Bi{sub 24}O{sub 31}Cl{sub 10} nanostructures have been investigated. Nanosheets with a thickness of ?10 nm and in-plane size of 30–60 nm were obtained in the as-synthesized BiOCl. The emission spectra excited at 360 nm consist of two broad emission bands: ultraviolet-blue and visible. The visible emission is responsible for the photocatalytic activity of BiOCl under visible light irradiation. The nanostructured Bi{sub 24}O{sub 31}Cl{sub 10}, self-assembled by uniform nanosheets with a thickness of 10–20 nm, exhibits a broad and strong blue shift UV emission at room temperature.

  2. PRECONDITIONED BI-CONJUGATE GRADIENT METHOD FOR RADIATIVE TRANSFER IN SPHERICAL MEDIA

    SciTech Connect (OSTI)

    Anusha, L. S.; Nagendra, K. N. [Indian Institute of Astrophysics, Koramangala, Bangalore 560 034 (India); Paletou, F.; Leger, L. [Laboratoire d'Astrophysique de Toulouse-Tarbes, Universite de Toulouse, CNRS, 14 Ave. E. Belin, 31400 Toulouse (France)

    2009-10-10T23:59:59.000Z

    A robust numerical method called the Preconditioned Bi-Conjugate Gradient (Pre-BiCG) method is proposed for the solution of the radiative transfer equation in spherical geometry. A variant of this method called Stabilized Preconditioned Bi-Conjugate Gradient (Pre-BiCG-STAB) is also presented. These are iterative methods based on the construction of a set of bi-orthogonal vectors. The application of the Pre-BiCG method in some benchmark tests shows that the method is quite versatile, and can handle difficult problems that may arise in astrophysical radiative transfer theory.

  3. Midea: Proposed Penalty (2013-SE-1505) | Department of Energy

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

    Midea Air-Conditioning Equipment Co. Ltd. manufactured and distributed noncompliant room air conditioner basic model MWJ1-08ERN1-BI8 in the U.S. Federal law subjects manufacturers...

  4. Thermoelectric power of Bi and Bi{sub 1{minus}x}Sb{sub x} alloy thin films and superlattices grown by MBE

    SciTech Connect (OSTI)

    Cho, S.; DiVenere, A.; Wong, G.K.; Ketterson, J.B.; Meyer, J.R.; Hoffman, C.A.

    1997-07-01T23:59:59.000Z

    The authors have measured the thermoelectric power (TEP) of MBE-grown epitaxial Bi and Bi{sub 1{minus}x} alloy thin films and superlattices as a function of temperature in the range 20--300 K. They have observed that the TEP of a Bi thin film of 1 {micro}m thickness is in good agreement with the bulk single crystal value and that the TEPs for superlattices with 400 {angstrom} and 800 {angstrom} Bi well thicknesses are enhanced over the bulk values. For x = 0.072 and 0.088 in Bi{sub 1{minus}x}Sb{sub x} thin films showing semiconducting behavior, TEP enhancement was observed by a factor of two. However as Bi or Bi{sub 1{minus}x}Sb{sub x} well thickness decreases in superlattice geometry, the TEP decreases, which may be due to unintentional p-type doping.

  5. Les minralisations Cu---(Ni---Bi---U---Au---Ag) d'Ifri (district du Haut Seksaoua, Maroc) : apport de l'tude

    E-Print Network [OSTI]

    Boyer, Edmond

    Les minéralisations Cu---(Ni---Bi---U---Au---Ag) d'Ifri (district du Haut Seksaoua, Maroc) : apport, université de Meknés, Meknés, Maroc c Snarema, Casablanca, Maroc Résumé Les minéralisations à Cu d'Ifri se; pyrite; stockwerk; cisaillement; Tardi-Hercynien; Haut Atlas; MarocMots- clé: copper; pyrite; stockwork

  6. DC and RF Measurements of Serial Bi-SQUID Arrays

    E-Print Network [OSTI]

    Prokopenko, G V; de Escobar, A Leese; Taylor, B; de Andrade, M C; Berggren, S; Longhini, P; Palacios, A; Nisenoff, M; Fagaly, R L

    2012-01-01T23:59:59.000Z

    SQUID arrays are promising candidates for low profile antennas and low noise amplifier applications. We present the integrated circuit designs and results of DC and RF measurements of the wideband serial arrays based on integration of linear bi-SQUID cells forming a Superconducting Quantum Interference Filter (bi-SQUID SQIF). Various configurations of serial arrays designs are described. The measured linearity, power gain, and noise temperature are analyzed and compared. The experimental results are matched to results of mathematical modeling. A serial bi-SQUID SQIF arrays are mounted into a coplanar waveguide (CPW) and symmetrically grounded to corresponding sides of CPW. The RF output comes out from the central common line, which is also used for DC biasing and forms a symmetrical balanced output. The signal and DC flux biasing line is designed as coplanar lines passed in parallel over each bi-SQUID cell in a bidirectional fashion concentrating magnetic flux inside of each cell. Serial bi-SQUID SQIF arrays ...

  7. Linking Family Background and Home Language with English Reading Comprehension amog Bi/Multilinguals 

    E-Print Network [OSTI]

    Yulia, Astri

    2013-04-24T23:59:59.000Z

    The purpose of this study is to examine the links between family background and home language factors on English reading achievement among bi/multilingual students. To explore the potential predictors of English reading achievement among bi...

  8. New York Event to Show Bi-Partisan, International Support for...

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

    New York Event to Show Bi-Partisan, International Support for Geothermal Energy in America New York Event to Show Bi-Partisan, International Support for Geothermal Energy in...

  9. ARTIGO INTERNET Spin Off PLUX Wireless Biosignals, S.A. assina acordo com CaixaBI

    E-Print Network [OSTI]

    Instituto de Sistemas e Robotica

    Alcoităo, Faculdade de Motricidade Humana e Academia do Sporting Clube de Portugal. O CaixaBi posiciona

  10. Lightest Isotope of Bh Produced Via the 209Bi(52Cr,n)260Bh Reaction

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    models. For many years, “cold fusion” reactions utilizingproduced via the new “cold fusion” reaction 209 Bi( 52 Cr,

  11. Advances in fabrication of Ag-clad Bi-2223 superconductors.

    SciTech Connect (OSTI)

    Balachandran, U.

    1998-09-04T23:59:59.000Z

    Powder-in-tube (PIT) processing was used to fabricate multifilamentary Ag-clad Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub y} (Bi-2223) superconductors for various electric power applications. Enhancements in the transport current properties of long lengths of multifilament tapes were achieved by increasing the packing density of the precursor powder, improving the mechanical deformation, and adjusting the cooling rate. The dependence of the critical current density on magnetic field and temperature for the optimally processed tapes was measured. J{sub c} was greater than 10{sup 4} (A/cm{sup 2}) at 20 K for magnetic field up to 3 T and parallel to the c-axis which is of interest for use in refrigerator coded magnets. An attempt was made to combine the good alignment of Bi-2223 grains in Ag-sheathed superconducting tapes to obtain high J{sub c} values at high temperature and low field, and good intrinsic pinning of YBa{sub 2}Cu{sub 3}O{sub 7{minus}d} (Y-123) thin film to maintain high J{sub c} values in high fields. A new composite multifilament tape was fabricated such that the central part contained Bi-2223 filaments, with the primary function of conducting the transport current. The central Bi-2223 filaments were surrounded by Y-123 thin film to shield the applied magnetic field and protect the Bi-2223 filaments. The J{sub c} values of the composite tape were better than those of an uncoated tape. In the case of 77 K applications, an I{sub c} of about 60 A was obtained in a 150 m long tape and zero applied magnetic field. In-situ strain characteristics of the mono- and multifilament tapes were conducted.

  12. Variation of lattice constant and cluster formation in GaAsBi

    SciTech Connect (OSTI)

    Puustinen, J.; Schramm, A.; Guina, M. [Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland)] [Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland); Wu, M.; Luna, E. [Paul-Drude Institut für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany)] [Paul-Drude Institut für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany); Laukkanen, P. [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland)] [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Laitinen, M.; Sajavaara, T. [Department of Physics, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä (Finland)] [Department of Physics, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä (Finland)

    2013-12-28T23:59:59.000Z

    We investigate the structural properties of GaAsBi layers grown by molecular beam epitaxy on GaAs at substrate temperatures between 220–315 °C. Irrespective of the growth temperature, the structures exhibited similar Bi compositions, and good overall crystal quality as deduced from X-Ray diffraction measurements. After thermal annealing at temperatures as low as 500 °C, the GaAsBi layers grown at the lowest temperatures exhibited a significant reduction of the lattice constant. The lattice variation was significantly larger for Bi-containing samples than for Bi-free low-temperature GaAs samples grown as a reference. Rutherford backscattering spectrometry gave no evidence of Bi diffusing out of the layer during annealing. However, dark-field and Z-contrast transmission electron microscopy analyses revealed the formation of GaAsBi clusters with a Bi content higher than in the surrounding matrix, as well as the presence of metallic As clusters. The apparent reduction of the lattice constant can be explained by a two-fold process: the diffusion of the excess As incorporated within As{sub Ga} antisites to As clusters, and the reduction of the Bi content in the GaAs matrix due to diffusion of Bi to GaAsBi clusters. Diffusion of both As and Bi are believed to be assisted by the native point defects, which are present in the low-temperature as-grown material.

  13. Wavelet Bi-frames with few Generators from Multivariate Refinable Functions

    E-Print Network [OSTI]

    Ehler, Martin

    Wavelet Bi-frames with few Generators from Multivariate Refinable Functions Martin Ehler Bin Han compactly supported wavelet bi-frames with few generators from almost any pair of compactly sup- ported multivariate refinable functions. In our examples, we focus on wavelet bi-frames whose primal and dual wavelets

  14. Thermoelectric Properties Modeling of Bi2Te3 Seungwon Lee and Paul von Allmen

    E-Print Network [OSTI]

    Goddard III, William A.

    Thermoelectric Properties Modeling of Bi2Te3 Seungwon Lee and Paul von Allmen Jet propulsion/23/2005 Overview · Introduce EZTB a modeling tool for thermoelectric properties using a tight-binding model-binding parameters for Bi2Te3. · Present the accuracy of the modeling tool with the thermoelectric properties of Bi2

  15. Bioavailability of Particle-Associated Se to the Bivalve Potamocorbula

    E-Print Network [OSTI]

    of Se(0) by generatingradioisotopic75Se(0)throughbacterialdissimilatory reduction of 75SeO3 2- by pure by reducing 75SeO3 2- with ascorbic acid (AA). Speciation determinations showed that AA and SES were >90% Se(0. After 113 d of incubation, 36% of SES Se(0) was oxidized to SeO3 2-. Assimilation of total particulate

  16. Simple shear processing of bulk BI?TE? alloys

    E-Print Network [OSTI]

    Im, Jae-taek

    2001-01-01T23:59:59.000Z

    The objective of this work is to determine the appropriate extrusion conditions of cast Bi?Te? alloys via equal channel angular extrusion (ECAE) to produce material that has a fine grain size (5~30[]m), uniform grain morphology and low grain...

  17. BiMOS II UNIPOLAR STEPPER-MOTOR

    E-Print Network [OSTI]

    Jain, Amit

    5804 BiMOS II UNIPOLAR STEPPER-MOTOR TRANSLATOR/DRIVER Combining low-power CMOS logic with high batwing package with a copper lead frame and heat-sinkable tabs for improved power dissipation. EP-021-4 OUT K TYPICAL OUTPUT DRIVER Dwg. EP-010-5 IN VDD Copyright © 1987, 1998, Allegro MicroSystems

  18. Development and Testing of a BI-2212 Textured Powder Conductor 

    E-Print Network [OSTI]

    Damborsky, Kyle

    2014-03-10T23:59:59.000Z

    to ascertain the quality of the products. The third and final thrust was the development of a non-melt heat treatment that was shown to grow grains of Bi-2212 powder and densify composites. Measurements of the transport critical currents for the heat treated...

  19. Development and Testing of a BI-2212 Textured Powder Conductor

    E-Print Network [OSTI]

    Damborsky, Kyle

    2014-03-10T23:59:59.000Z

    Superconducting wires based on the high field superconductor Bi_(2)Sr_(2)Ca_(1)Cu_(2)O_(8)+x are an enabling technology for the development of very high field (>18 T) magnets. While these conductors have the potential to serve as the conductors...

  20. Aluminum Removal from Photographic Waste Submitted to Dr. Tony Bi

    E-Print Network [OSTI]

    Aluminum Removal from Photographic Waste Submitted to Dr. Tony Bi By: Kristen Favel, Tiffany Jung, and Kenny Tam CHBE 484 University of British Columbia April 15, 2009 #12;ii "Aluminum Removal from photographic waste has shown elevated levels of aluminum in the fixer, which exceed sewer discharge standards

  1. Bi-harmonic cantilever design for improved measurement sensitivity in tapping-mode atomic force microscopy

    SciTech Connect (OSTI)

    Loganathan, Muthukumaran; Bristow, Douglas A., E-mail: dbristow@mst.edu [Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri 65401 (United States)

    2014-04-15T23:59:59.000Z

    This paper presents a method and cantilever design for improving the mechanical measurement sensitivity in the atomic force microscopy (AFM) tapping mode. The method uses two harmonics in the drive signal to generate a bi-harmonic tapping trajectory. Mathematical analysis demonstrates that the wide-valley bi-harmonic tapping trajectory is as much as 70% more sensitive to changes in the sample topography than the standard single-harmonic trajectory typically used. Although standard AFM cantilevers can be driven in the bi-harmonic tapping trajectory, they require large forcing at the second harmonic. A design is presented for a bi-harmonic cantilever that has a second resonant mode at twice its first resonant mode, thereby capable of generating bi-harmonic trajectories with small forcing signals. Bi-harmonic cantilevers are fabricated by milling a small cantilever on the interior of a standard cantilever probe using a focused ion beam. Bi-harmonic drive signals are derived for standard cantilevers and bi-harmonic cantilevers. Experimental results demonstrate better than 30% improvement in measurement sensitivity using the bi-harmonic cantilever. Images obtained through bi-harmonic tapping exhibit improved sharpness and surface tracking, especially at high scan speeds and low force fields.

  2. Interfacing 2D and 3D Topological Insulators: Bi(111) Bilayer on Bi2Te3 Toru Hirahara,1,* Gustav Bihlmayer,2

    E-Print Network [OSTI]

    Hasegawa, Shuji

    Interfacing 2D and 3D Topological Insulators: Bi(111) Bilayer on Bi2Te3 Toru Hirahara,1,* Gustav Topological insulators, realized in materials with strong spin-orbit interaction, are gaining increasing-dimensional (1D) edge states compared to the 2D surface states of 3D topological insulators, only a few works

  3. ECOLOGY LECTURE (BI 40601) & LABORATORY (BI40711) Lecture Fischer 316, TTH 10:0011:35; Lab Fischer 224, M 1:004:00

    E-Print Network [OSTI]

    Packer, Alissa A.

    ECOLOGY LECTURE (BI 40601) & LABORATORY (BI40711) FALL 2005 Lecture Fischer 316, TTH 10 EMAILpacker@susqu.edu OFFICE HOURS MW 9:0010:00, W 1:302:30 WHAT IS ECOLOGY? Ecology is the study of interrelationships between organisms and their biotic and abiotic environments. As a basic science, ecology informs

  4. Wi-Bi KTH Stockholm -TU Darmstadt Kurswahl Wi-Bi Department an der KTH: School of Architecture and Built Environmentv (ABE)

    E-Print Network [OSTI]

    Haller-Dintelmann, Robert

    Infrastructure Civil and Architectural Engineering Transport and Geoinformation Technology Sustainable UrbanWi-Bi KTH Stockholm - TU Darmstadt Kurswahl Wi-Bi Department an der KTH: School of Architecture ABE gewählt werden. Momentan von der ABE angebotene Programme: Architecture Real Estate Construction

  5. Onset of deformation at $N = 112$ in Bi nuclei

    E-Print Network [OSTI]

    H. Pai; G. Mukherjee; R. Raut; S. K. Basu; A. Goswami; S. Chanda; T. Bhattacharjee; S. Bhattacharyya; C. Bhattacharya; S. Bhattacharya; S. R. Banerjee; S. Kundu; K. Banerjee; A. Dey; T. K. Rana; J. K. Meena; D. Gupta; S. Mukhopadhyay; Srijit Bhattacharya; Sudeb Bhattacharya; S. Ganguly; R. Kshetri; M. K. Pradhan

    2012-04-19T23:59:59.000Z

    The high spin states in $^{195}$Bi has been studied by $\\gamma$-ray spectroscopic method using the $^{181}$Ta($^{20}$Ne, 6n) fusion evaporation reaction at 130 MeV. The $\\gamma\\gamma$ coincidence data were taken using an array of 8 clover HPGe detectors. The spin and parity assignments of the excited states have been made from the measured directional correlation from oriented states (DCO) ratios and integrated polarization asymmetry (IPDCO) ratios. The results show, for the first time, the evidence of a rotational like band based on a 13/2$^+$ band head in this nucleus, indicating the onset of deformation at neutron number $N = 112$ for the Bismuth isotopes. The results obtained were found to be consistent with the prediction of the total Routhian surface calculations using Woods Saxon potential. The same calculations also predict a change in shape from oblate to triaxial in $^{195}$Bi at high rotational frequency.

  6. Canonoid and Poissonoid Transformations, Symmetries and BiHamiltonian Structures

    E-Print Network [OSTI]

    Giovanni Rastelli; Manuele Santoprete

    2015-02-25T23:59:59.000Z

    We give a characterization of linear canonoid transformations on symplectic manifolds and we use it to generate biHamiltonian structures for some mechanical systems. Utilizing this characterization we also study the behavior of the harmonic oscillator under canonoid transformations. We present a description of canonoid transformations due to E.T. Whittaker, and we show that it leads, in a natural way, to the modern, coordinate-independent definition of canonoid transformations. We also generalize canonoid transformations to Poisson manifolds by introducing Poissonoid transformations. We give examples of such transformations for Euler's equations of the rigid body (on $\\mathcal{so}^\\ast (3) $ and $ so^\\ast (4)$) and for an integrable case of Kirchhoff's equations for the motion of a rigid body immersed in an ideal fluid. We study the relationship between biHamiltonian structures and Poissonoid transformations for these examples. We analyze the link between Poissonoid transformations, constants of motion, and symmetries.

  7. Q Cells SE | 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 being directedAnnualProperty Edit with form History Facebook icon TwitterZip JumpProwindPudaPvT CapitalQ Cells SE

  8. The optical torque on small bi-isotropic particles

    E-Print Network [OSTI]

    Nieto-Vesperinas, Manuel

    2015-01-01T23:59:59.000Z

    Most previous theoretical studies on the optical torque exerted by light on dipolar particles are incomplete. Here we establish the equations for the time-averaged optical torque on dipolar bi-isotropic particles. Due to the interference of scattered fields, it has a term additional to that commonly employed in theory and experiments. Its consequences for conservation of energy, angular momentum, and effects like negative torques, are discussed.

  9. Bulk from Bi-locals in Thermo Field CFT

    E-Print Network [OSTI]

    Jevicki, Antal

    2015-01-01T23:59:59.000Z

    We study the Large $N$ dynamics of the $O(N)$ field theory in the Thermo field approach. Concentrating on the singlet bi-local space within the systematic $1/N$ framework of collective field theory we discuss the emergent bulk space-time and construct the associated (Higher spin) fields. We note the presence of `evanescent' modes in this construction and also the mixing of spins at finite temperature.

  10. Bulk from Bi-locals in Thermo Field CFT

    E-Print Network [OSTI]

    Antal Jevicki; Junggi Yoon

    2015-03-29T23:59:59.000Z

    We study the Large $N$ dynamics of the $O(N)$ field theory in the Thermo field approach. Concentrating on the singlet bi-local space within the systematic $1/N$ framework of collective field theory we discuss the emergent bulk space-time and construct the associated (Higher spin) fields. We note the presence of `evanescent' modes in this construction and also the mixing of spins at finite temperature.

  11. Itinerant effects and enhanced magnetic interactions in Bi-based multilayer cuprates

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

    Dean, M. P. M.; James, A. J. A.; Walters, A. C.; Bisogni, V.; Jarrige, I.; Hucker, M.; Giannini, E.; Fujita, M.; Huang, Y.; Konik, R. M.; et al

    2014-12-01T23:59:59.000Z

    The cuprate high temperature superconductors exhibit a pronounced trend in which the superconducting transition temperature, T c, increases with the number of CuO? planes, n, in the crystal structure. We compare the magnetic excitation spectrum of Bi??xSr??xCuO?+? (Bi-2201) and Bi?Sr?Ca?Cu?O???? (Bi-2223), with n = 1 and n = 3 respectively, using Cu L?-edge resonant inelastic x-ray scattering (RIXS). Near the anti-nodal zone boundary we find the paramagnon energy in Bi-2223 is substantially higher than that in Bi-2201, indicating that multilayer cuprates host stronger effective magnetic exchange interactions, providing a possible explanation for the Tc vs. n scaling. In contrast, themore »nodal direction exhibits very strongly damped, almost non-dispersive excitations. We argue that this implies that the magnetism in the doped cuprates is partially itinerant in nature.« less

  12. Itinerant effects and enhanced magnetic interactions in Bi-based multilayer cuprates

    SciTech Connect (OSTI)

    Dean, M. P. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.; James, A. J. A. [University College London, London, United Kingdom (England); Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.; Walters, A. C. [Harwell Science and Innovation Campus, Chilton, Didcot, United Kingdom (England). Diamond Light Source Ltd.; Bisogni, V. [Brookhaven National Lab. (BNL), Upton, NY (United States). Photon Sciences Directorate; Paul Scherrer Inst. (PSI), Villigen (Switzerland); Jarrige, I. [Brookhaven National Lab. (BNL), Upton, NY (United States). Photon Sciences Directorate.; Hucker, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.; Giannini, E. [Universite de Geneve, Geneve (Switzerland). Departement de Physique de la Matiere Condensee; Fujita, M. [Tohoku Univ., Sendai (Japan). Institute for Materials Research; Huang, Y. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Konik, R. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.; Schmitt, T. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Pelliciar, J. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Hill, J. P. [Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.

    2014-12-01T23:59:59.000Z

    The cuprate high temperature superconductors exhibit a pronounced trend in which the superconducting transition temperature, T c, increases with the number of CuO? planes, n, in the crystal structure. We compare the magnetic excitation spectrum of Bi??xSr??xCuO?+? (Bi-2201) and Bi?Sr?Ca?Cu?O???? (Bi-2223), with n = 1 and n = 3 respectively, using Cu L?-edge resonant inelastic x-ray scattering (RIXS). Near the anti-nodal zone boundary we find the paramagnon energy in Bi-2223 is substantially higher than that in Bi-2201, indicating that multilayer cuprates host stronger effective magnetic exchange interactions, providing a possible explanation for the Tc vs. n scaling. In contrast, the nodal direction exhibits very strongly damped, almost non-dispersive excitations. We argue that this implies that the magnetism in the doped cuprates is partially itinerant in nature.

  13. Itinerant effects and enhanced magnetic interactions in Bi-based multilayer cuprates

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

    Dean, M. P. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.; James, A. J. A. [University College London, London, United Kingdom (England); Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.; Walters, A. C. [Harwell Science and Innovation Campus, Chilton, Didcot, United Kingdom (England). Diamond Light Source Ltd.; Bisogni, V. [Brookhaven National Lab. (BNL), Upton, NY (United States). Photon Sciences Directorate; Paul Scherrer Inst. (PSI), Villigen (Switzerland); Jarrige, I. [Brookhaven National Lab. (BNL), Upton, NY (United States). Photon Sciences Directorate.; Hucker, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.; Giannini, E. [Universite de Geneve, Geneve (Switzerland). Departement de Physique de la Matiere Condensee; Fujita, M. [Tohoku Univ., Sendai (Japan). Institute for Materials Research; Huang, Y. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Konik, R. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.; Schmitt, T. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Pelliciar, J. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Hill, J. P. [Brookhaven National Lab. (BNL), Upton, NY (United States). Department of Condensed Matter Physics and Materials Science.

    2014-12-01T23:59:59.000Z

    The cuprate high temperature superconductors exhibit a pronounced trend in which the superconducting transition temperature, T c, increases with the number of CuO? planes, n, in the crystal structure. We compare the magnetic excitation spectrum of Bi??xSr??xCuO?+? (Bi-2201) and Bi?Sr?Ca?Cu?O???? (Bi-2223), with n = 1 and n = 3 respectively, using Cu L?-edge resonant inelastic x-ray scattering (RIXS). Near the anti-nodal zone boundary we find the paramagnon energy in Bi-2223 is substantially higher than that in Bi-2201, indicating that multilayer cuprates host stronger effective magnetic exchange interactions, providing a possible explanation for the Tc vs. n scaling. In contrast, the nodal direction exhibits very strongly damped, almost non-dispersive excitations. We argue that this implies that the magnetism in the doped cuprates is partially itinerant in nature.

  14. Temperature dependent band offsets in PbSe/PbEuSe quantum well heterostructures

    SciTech Connect (OSTI)

    Simma, M.; Bauer, G.; Springholz, G. [Institut fuer Halbleiter und Festkoerperphysik, Johannes Kepler Universitaet, A-4040 Linz (Austria)

    2012-10-22T23:59:59.000Z

    The band offsets of PbSe/Pb{sub 1-x}Eu{sub x}Se multi-quantum wells grown by molecular beam epitaxy are determined as a function of temperature and europium content using temperature-modulated differential transmission spectroscopy. The confined quantum well states in the valence and conduction bands are analyzed using a k{center_dot}p model with envelope function approximation. From the fit of the experimental data, the normalized conduction band offset is determined as 0.45{+-}0.15 of the band gap difference, independently of Eu content up to 14% and temperature from 20 to 300 K.

  15. Reaction kinetics of a-CuInSe2 formation from an In2Se3/CuSe bilayer precursor film

    E-Print Network [OSTI]

    Anderson, Timothy J.

    with Ga or S are proven absorber materials for high efficiency thin film solar cells. Interestingly CIGS system using the stacked elemental film precursors (e.g. glass/Cu/In/Se, glass/Cu/Se, glass

  16. Influence of Bi on the Er luminescence in yttrium-erbium disilicate thin films

    SciTech Connect (OSTI)

    Scarangella, Adriana [MATIS-IMM CNR, Via S. Sofia 64, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Universitŕ di Catania, Via S. Sofia 64, 95123 Catania (Italy); Miritello, Maria, E-mail: maria.miritello@ct.infn.it [MATIS-IMM CNR, Via S. Sofia 64, 95123 Catania (Italy); Priolo, Francesco [MATIS-IMM CNR, Via S. Sofia 64, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Universitŕ di Catania, Via S. Sofia 64, 95123 Catania (Italy); Scuola Superiore di Catania, Universitŕ di Catania, Via Valdisavoia 9, 95123 Catania (Italy)

    2014-09-28T23:59:59.000Z

    The influence of bismuth on erbium optical properties at 1.54??m has been investigated in yttrium-erbium disilicate thin films synthesized by magnetron co-sputtering and implanted with two Bi different doses. The Bi depth distribution and the evolution of its oxidation states after annealing treatments at 1000?°C in two atmospheres, O{sub 2} and N{sub 2}, have been investigated. It was found that only in O{sub 2} the Bi{sup 3+} valence state is prevalent, thanks to the enhanced Bi mobility in the oxidizing ambient, as demonstrated by Rutherford backscattering spectrometry. At lower Bi content, although the formation of Bi{sup 0} metallic nanoparticles that are deleterious non radiative channels for Er luminescence, efficient energy transfer from Bi to Er has been obtained only in O{sub 2}. It is due to the excitation of ultraviolet broad Bi{sup 3+} absorption band and the energy transfer to Er ions. We have evaluated that in this case, Er effective excitation cross section increased by a factor of 5 in respect with the one for direct Er absorption at 488?nm. At higher Bi dose, this mechanism is absent, but an increased Er optical efficiency at 1.54??m has been observed under resonant excitation. It is due to the contribution of a fraction of Er ions having an increased lifetime. This phenomenon is associated with the formation of Bi agglomerates, induced at higher Bi doses, which well isolate Er from non-radiative quenching centers. The increased decay time assures higher optical efficiency at 1.54??m.

  17. Bi-Directional DC-DC Converter for PHEV Applications

    SciTech Connect (OSTI)

    Abas Goodarzi

    2011-01-31T23:59:59.000Z

    Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

  18. BiBB Western Region | 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 being directedAnnualProperty EditCalifornia: EnergyAvignon,Belcher Homes JumpMaintenance | OpenBetterBiBB Western

  19. Bi-Con Services Inc | 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:EzfeedflagBiomass ConversionsSouth Carolina:Energy LLC Place:BeverlyBeyWatchBhutanBi-Con

  20. Synthesis and optical study of green light emitting polymer coated CdSe/ZnSe core/shell nanocrystals

    SciTech Connect (OSTI)

    Tripathi, S.K., E-mail: surya@pu.ac.in [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh 160 014 (India); Sharma, Mamta [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh 160 014 (India)

    2013-05-15T23:59:59.000Z

    Highlights: ? Synthesis of Polymer coated core CdSe and CdSe/ZnSe core/shell NCs. ? From TEM image, the spherical nature of CdSe and CdSe/ZnSe is obtained. ? Exhibiting green band photoemission peak at 541 nm and 549 nm for CdSe core and CdSe/ZnSe core/shell NCs. ? The shell thickness has been calculated by using superposition of quantum confinement energy model. - Abstract: CdSe/ZnSe Core/Shell NCs dispersed in PVA are synthesized by chemical method at room temperature. This is characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV/Vis spectra and photoluminescence spectroscopy (PL). TEM image shows the spherical nature of CdSe/ZnSe core/shell NCs. The red shift of absorption and emission peak of CdSe/ZnSe core/shell NCs as compared to CdSe core confirmed the formation of core/shell. The superposition of quantum confinement energy model is used for calculation of thickness of ZnSe shell.

  1. We report two-dimensional (2D) Dirac fermions and quantum magnetoresistance (MR) in Bi square nets of CaMnBi2 crystals.

    E-Print Network [OSTI]

    Weston, Ken

    in monolayer graphene and topological insulators. Our results imply that a wide range of bulk crystals with Bi found so far in 2D materials such as graphene and topological insulators. Relativistic Fermions

  2. Photovoltaic effect in multiphase Bi-Mn-O thin J. P. Chakrabartty,1

    E-Print Network [OSTI]

    Photovoltaic effect in multiphase Bi-Mn-O thin films J. P. Chakrabartty,1 R. Nechache,2,4 C and therefore the photovoltaic conversion efficiency. Specifically, a higher Bi/Mn ratio (towards unity separation. ©2013 Optical Society of America OCIS codes: (040.5350) Photovoltaic; (160.2260) Ferroelectrics

  3. Effect of doping in Bi-Pb-Sr-Ca-Cu-O superconductor composites

    E-Print Network [OSTI]

    Ertekin, Abdullah

    2001-01-01T23:59:59.000Z

    The goal of this thesis is to analyze the solid solubility limit of dopants in Bi-Pb-Sr-Ca-Cu-O superconductors. We have studied the effect of Mn doping Bi-Pb-Sr-Ca-Cu-O. The electrical resistivity and critical temperature were measured for samples...

  4. Development of a Microfluidic Device for Synthesis of Lipid Bi-Layer In-Situ

    E-Print Network [OSTI]

    Banneyake, Bm U.

    2010-01-14T23:59:59.000Z

    and result in unstable bi-layers having a short lifetime. In this investigation a novel microfluidic device and a method for artificial synthesis of lipid bi-layer in-situ are explored. In the proposed method, lipid trapped at an aperture on a Teflon sheet...

  5. An Electrothermally-Actuated, Dual-Mode Micromirror for Large Bi-Directional Scanning

    E-Print Network [OSTI]

    Bowers, John

    An Electrothermally-Actuated, Dual-Mode Micromirror for Large Bi-Directional Scanning Ankur Jain-crystal-silicon (SCS)-based micromirror that can perform large bi-directional scans and can also generate large piston scan angle) at its resonance of 2.4 kHz. A maximum vertical piston motion of 200 µm is also achieved

  6. Multiple Access and Two-way Channels with Energy Harvesting and Bi-directional

    E-Print Network [OSTI]

    Yener, Aylin

    Multiple Access and Two-way Channels with Energy Harvesting and Bi-directional Energy Cooperation@ee.psu.edu Abstract--This paper considers the multiple access and two- way channels with energy harvesting, and optimal policies were found using a two-dimensional water-filling algorithm. In this paper, the bi

  7. Sensors and Actuators A 136 (2007) 426433 A bi-polymer micro one-way valve

    E-Print Network [OSTI]

    Beebe, David J.

    2007-01-01T23:59:59.000Z

    Sensors and Actuators A 136 (2007) 426­433 A bi-polymer micro one-way valve Dongshin Kima,b,, David December 2006 Abstract We have developed an in-plane bi-polymer check-valve for controlling microfluidic hydrogel. The valve was created using microfluidic tectonics, a fabrication procedure that allows

  8. Switchable diode effect and ferroelectric resistive switching in epitaxial BiFeO3 thin films

    E-Print Network [OSTI]

    Tian, Weidong

    Switchable diode effect and ferroelectric resistive switching in epitaxial BiFeO3 thin films Can observed in epitaxial multiferroic BiFeO3 BFO thin films. The forward direction of the rectifying current the switchable diode effect and the ferroelectric resistive switching in epitaxially BFO thin films. BFO thin

  9. Spontaneous and deterministic three-dimensional curling of pre-strained elastomeric bi-strips

    E-Print Network [OSTI]

    ) begin to form. After release, the coiled bi-elas- tomer strip adopts the shape shown in (b). For clarity and shown at the same magnification, consisting of a tightly wound coil with the inner portion being red strip and then releasing the bi-strip formed. The hemi- helix shape consists of periodic and alternating

  10. Large pyramid shaped single crystals of BiFeO{sub 3} by solvothermal synthesis method

    SciTech Connect (OSTI)

    Sornadurai, D.; Ravindran, T. R.; Paul, V. Thomas; Sastry, V. Sankara [Condensed Matter Physics Division, Materials Science Group, Physical Metallurgy Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu (India); Condensed Matter Physics Division, Materials Science Group (India)

    2012-06-05T23:59:59.000Z

    Synthesis parameters are optimized in order to grow single crystals of multiferroic BiFeO{sub 3}. 2 to 3 mm size pyramid (tetrahedron) shaped single crystals were successfully obtained by solvothermal method. Scanning electron microscopy with EDAX confirmed the phase formation. Raman scattering spectra of bulk BiFeO3 single crystals have been measured which match well with reported spectra.

  11. A 7-decades Tunable Translinear SiGe BiCMOS 3-phase Sinusoidal Oscillator

    E-Print Network [OSTI]

    Cauwenberghs, Gert

    A 7-decades Tunable Translinear SiGe BiCMOS 3-phase Sinusoidal Oscillator Dimitrios N. Loizos 1 of these controls to external current biases. Measurements on a 0.5m SiGe BiCMOS implementation of the architecture

  12. A translinear SiGe BiCMOS current-controlled oscillator with 80 Hz800 MHz tuning range

    E-Print Network [OSTI]

    Cauwenberghs, Gert

    A translinear SiGe BiCMOS current-controlled oscillator with 80 Hz­800 MHz tuning range Dimitrios N, as a function of two current biases. Experimental results from a 0.5 lm SiGe BiCMOS chip demonstrate 7 decades. Keywords Current-controlled oscillator Á Translinear circuits Á Amplitude and frequency control Á SiGe Bi

  13. Synthesis of BiPbSrCaCuO superconductor

    DOE Patents [OSTI]

    Hults, William L. (Los Alamos, NM); Kubat-Martin, Kimberly A. (Espanola, NM); Salazar, Kenneth V. (Espanola, NM); Phillips, David S. (Los Alamos, NM); Peterson, Dean E. (Los Alamos, NM)

    1994-01-01T23:59:59.000Z

    A process and a precursor composition for preparing a lead-doped bismuth-strontium-calcium-copper oxide superconductor of the formula Bi.sub.a Pb.sub.b Sr.sub.c Ca.sub.d Cu.sub.e O.sub.f wherein a is from about 1.7 to about 1.9, b is from about 0.3 to about 0.45, c is from about 1.6 to about 2.2, d is from about 1.6 to about 2.2, e is from about 2.97 to about 3.2 and f is 10.+-.z by reacting a mixture of Bi.sub.4 Sr.sub.3 Ca.sub.3 Cu.sub.4 O.sub.16.+-.z, an alkaline earth metal cuprate, e.g., Sr.sub.9 Ca.sub.5 Cu.sub.24 O.sub.41, and an alkaline earth metal plumbate, e.g., Ca.sub.2-x Sr.sub.x PbO.sub.4 wherein x is about 0.5, is disclosed.

  14. Electromagnetic properties of Bi-2223/Ag concentric tapes

    SciTech Connect (OSTI)

    Majoros, M.; Polak, M.; Kvitkovic, J.; Suchon, D. [Slovak Academy of Sciences, Bratislava (Slovakia). Inst. of Electrical Engineering] [Slovak Academy of Sciences, Bratislava (Slovakia). Inst. of Electrical Engineering; Martini, L.; Ottoboni, V.; Zannella, S. [CISE SpA, Segrate (Italy)] [CISE SpA, Segrate (Italy)

    1996-07-01T23:59:59.000Z

    It is well established that near the silver interface highly textured Bi-2223 layers compared to the inner ceramic core may be obtained. Thus Bi-2223 multilayered concentric tapes with silver matrix are very promising in increasing transport critical current densities. In the present work the authors report on the electromagnetic characterization of short tapes having in their cross-section a very thin HTS flattened ring with Ag inside and outside of it. The samples were prepared by the powder in tube method and have self-field critical current densities J{sub c} of the order of 3 {times} 10{sup 4} A/cm{sup 2} at 77 K. Transport and SQUID magnetization measurements revealed weak link nature of the samples in low magnetic fields. Large transport J{sub c}(B) hysteresis was observed at 4.2 K and magnetic fields up to 20 T. Magnetic field profiles measurements with miniature Hall sensors are in qualitative accordance with model calculations supposing homogeneous current density distribution across the superconducting core.

  15. Synthesis of BiPbSrCaCuO superconductor

    DOE Patents [OSTI]

    Hults, W.L.; Kubat-Martin, K.A.; Salazar, K.V.; Phillips, D.S.; Peterson, D.E.

    1994-04-05T23:59:59.000Z

    A process and a precursor composition for preparing a lead-doped bismuth-strontium-calcium-copper oxide superconductor of the formula Bi[sub a]Pb[sub b]Sr[sub c]Ca[sub d]Cu[sub e]O[sub f] wherein a is from about 1.7 to about 1.9, b is from about 0.3 to about 0.45, c is from about 1.6 to about 2.2, d is from about 1.6 to about 2.2, e is from about 2.97 to about 3.2 and f is 10[+-]z by reacting a mixture of Bi[sub 4]Sr[sub 3]Ca[sub 3]Cu[sub 4]O[sub 16[+-]z], an alkaline earth metal cuprate, e.g., Sr[sub 9]Ca[sub 5]Cu[sub 24]O[sub 41], and an alkaline earth metal plumbate, e.g., Ca[sub 2[minus]x]Sr[sub x]PbO[sub 4] wherein x is about 0.5, is disclosed.

  16. Size dependent structural, vibrational and magnetic properties of BiFeO{sub 3} and core-shell structured BiFeO{sub 3}@SiO{sub 2} nanoparticles

    SciTech Connect (OSTI)

    Chauhan, Sunil, E-mail: sunilchauhanjiit@gmail.com; Kumar, Manoj, E-mail: sunilchauhanjiit@gmail.com; Chhoker, Sandeep, E-mail: sunilchauhanjiit@gmail.com; Katyal, S. C., E-mail: sunilchauhanjiit@gmail.com [Department of Physics and Materials Science and Engineering, Jaypee Institute of Information Technology, Noida- 201307 (India)

    2014-04-24T23:59:59.000Z

    Bulk BiFeO{sub 3}, BiFeO{sub 3} nanoparticles and core-shell structured BiFeO{sub 3}@SiO{sub 2} nanoparticles were synthesized by solid state reaction method, sol-gel and Stöber process (SiO{sub 2} shell) respectively. Transmission electron microscopy image confirmed the core-shell structure of BiFeO{sub 3}@SiO{sub 2} nanoparticles with BiFeO3 core ?50-90 nm and SiO{sub 2} shell ?16 nm. X-ray diffraction and FTIR spectroscopy results showed the presence of distorted rhombohedral structure with R3c space group in all three samples. The magnetic measurement indicated the existence of room-temperature weak ferromagnetism in core-shell BiFeO{sub 3}@SiO{sub 2} nanoparticles and BiFeO3 nanoparticles, whereas bulk BiFeO{sub 3} showed antiferromagnteic nature. Electron Spin Resonance results confirmed the enhancement in magnetic properties of coreshell structured BiFeO{sub 3}@SiO{sub 2} nanoparticles in comparison with BiFeO{sub 3} nanoparticles and bulk BiFeO{sub 3}.

  17. Liquid immiscibility and core-shell morphology formation in ternary Al–Bi–Sn alloys

    SciTech Connect (OSTI)

    Dai, R.; Zhang, J.F.; Zhang, S.G., E-mail: sgzhang@sjtu.edu.cn; Li, J.G.

    2013-07-15T23:59:59.000Z

    The effects of composition on liquid immiscibility, macroscopic morphology, microstructure and phase transformation in ternary Al–Bi–Sn alloys were investigated. Three types of morphology, the core-shell type, the stochastic droplet type and uniform dispersion type, of Al–Bi–Sn particles prepared by a jet breakup process were distinguished, and the relationships between which were discussed. The phase transformation behaviors of the Al–Bi–Sn alloys were studied by thermal analysis, in agreement with the microstructural observation and microanalysis. The liquid immiscibility and formation of the core-shell morphology in Al–Bi–Sn alloys are easily achieved when the composition lies in the liquid miscibility gap. The particles exhibit a high melting point Al-rich core with a low melting point Sn–Bi-rich solder shell, showing promise for application as high-density electronic packaging materials. - Highlights: • The liquid demixing, morphology and microstructure in Al–Bi–Sn alloys were studied. • Three types of morphology were classified and discussed. • The conditions for formation of the core-shell morphology were obtained. • The phase transition behaviors agree with the microstructure characterization. • The Al/Sn–Bi core-shell particles show promise for use in electronic packaging.

  18. Cotinga Alirrufa La Cotinga Alirrufa se distribuye en

    E-Print Network [OSTI]

    Cuervo, Andrés

    . inventarios y su estudio, la situaciĂłn actual de esta especie en Colombia. Se considera casi Aphanotriccus

  19. 31P Solid State NMR Studies of Metal Selenophosphates Containing [P2Se6]4-, [P4Se10]4-, [PSe4]3-, [P2Se7]4-, and [P2Se9]4-Ligands

    E-Print Network [OSTI]

    Weliky, David

    31P Solid State NMR Studies of Metal Selenophosphates Containing [P2Se6]4-, [P4Se10]4-, [PSe4]3-, [P2Se7]4-, and [P2Se9]4- Ligands Christian G. Canlas, Mercouri G. Kanatzidis, and David P. Weliky P solid-state nuclear magnetic resonance (NMR) spectra of 12 metal-containing selenophosphates have

  20. Facile synthesis of novel Ag/AgI/BiOI composites with highly enhanced visible light photocatalytic performances

    SciTech Connect (OSTI)

    Cao, Jing, E-mail: caojing@mail.ipc.ac.cn [College of Chemistry and Materials Science, Huaibei Normal University, Huaibei 235000, Anhui (China); State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100 (China); Zhao, Yijie; Lin, Haili; Xu, Benyan [College of Chemistry and Materials Science, Huaibei Normal University, Huaibei 235000, Anhui (China); Chen, Shifu, E-mail: chshifu@chnu.edu.cn [College of Chemistry and Materials Science, Huaibei Normal University, Huaibei 235000, Anhui (China)

    2013-10-15T23:59:59.000Z

    Novel Ag/AgI/BiOI composites were controllably synthesized via a facile ion-exchange followed by photoreduction strategy by using hierarchical BiOI microflower as substrate. The as-prepared Ag/AgI/BiOI composites were studied by X-ray powder diffractometer (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) surface area analyzer and UV–vis diffuse reflectance spectroscopy (DRS). Under visible light (?>420 nm), Ag/AgI/BiOI displayed highly enhanced photocatalytic activities for degradation of methyl orange (MO) compared to the pure hierarchical BiOI, which was mainly ascribed to the highly efficient separation of electrons and holes through the closely contacted interfaces in the Ag/AgI/BiOI ternary system. - Graphical abstract: Ag/AgI/BiOI displayed excellent photocatalytic activities for methyl orange degradation under visible light, which was mainly ascribed to the highly efficient separation of electrons and holes through Z-scheme pathway. Display Omitted - Highlights: • Novel Ag/AgI/BiOI composites were successfully synthesized. • Ag/AgI/BiOI displayed higher visible light activities than those of pure BiOI and AgI. • ·O{sub 2}{sup ?} and h{sup +}, especially ·O{sub 2}{sup ?}, dominated the photodegradation process of MO. • A Z-scheme pattern was adopted for Ag/AgI/BiOI activity enhancement.

  1. Evidence against a charge density wave on Bi(111)

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

    Kim, T.; Wells, J.; Kirkegaard, C.; Li, Z.; Hoffmann, S.; Gayone, J.; Fernandez-Torrente, I.; Haberle, P.; Pascual, J.; Moore, K.; Schwartz, A.; He, H.; Spence, J.; Downing, K.; Lazar, S.; Tichelaar, F.; Borisenko, S.; Knupfer, M.; Hofmann, Ph.

    2005-08-01T23:59:59.000Z

    The Bi(111) surface was studied by scanning tunneling microscopy (STM), transmission electron microscopy (TEM) and angle-resolved photoemission (ARPES) in order to verify the existence of a recently proposed surface charge density wave (CDW) [Ch. R. Ast and H. H¨ochst Phys. Rev. Lett. 90, 016403 (2003)]. The STM and TEM results to not support a CDW scenario at low temperatures. Furthermore, the quasiparticle interference pattern observed in STM confirms the spin-orbit split character of the surface states which prevents the formation of a CDW, even in the case of good nesting. The dispersion of the electronic states observed with ARPES agrees well with earlier findings. In particular, the Fermi contour of the electron pocket at the centre of the surface Brillouin zone is found to have a hexagonal shape. However, no gap opening or other signatures of a CDW phase transition can be found in the temperature-dependent data.

  2. Bi-2223: prospects for further developments in critical current performance

    SciTech Connect (OSTI)

    Holesinger, T. G. (Terry G.); Bingert, J. F. (John F.)

    2001-01-01T23:59:59.000Z

    Bi-2223 is the available high temperature superconductor (HTS) conductor. It is being made in long lengths in significant quantities to serve increasingly large and more diverse applications. Strong near term prospects for significant applications, particularly for power cables, are leading to major production capacity scale up, a very significant factor in decreasing conductor cost. To supply recent large project conductor runs has required much successful attention to details of piece length, performance uniformity, yield and reproducibility. Study of the basic materials science of such conductors is particularly valuable because the lessons learned are on state-of-the-art materials and have direct production relevance. The present state of recent studies of high performance conductors within the Wire Development Group is briefly discussed.

  3. Observation of a Warped Helical Spin Texture in Bi[subscript 2]Se[subscript 3] from Circular Dichroism Angle-Resolved Photoemission Spectroscopy

    E-Print Network [OSTI]

    Wang, Y. H.

    A differential coupling of topological surface states to left- versus right-circularly polarized light is the basis of many optospintronics applications of topological insulators. Here we report direct evidence of circular ...

  4. Photoemission Spectroscopy of Magnetic and Nonmagnetic Impurities on the Surface of the Bi[subscript 2]Se[subscript 3] Topological Insulator

    E-Print Network [OSTI]

    Valla, T.

    Dirac-like surface states on surfaces of topological insulators have a chiral spin structure that suppresses backscattering and protects the coherence of these states in the presence of nonmagnetic scatterers. In contrast, ...

  5. Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots

    SciTech Connect (OSTI)

    Kaur, Gurvir; Kaur, Harmandeep [Centre of Advanced Study in Physics, Department of Physics, Panjab University, Chandigarh-160014 (India); Tripathi, S. K., E-mail: surya@pu.ac.in [Centre of Advanced Study in Physics, Panjab University, Chandigarh- 160014 (India)

    2014-04-24T23:59:59.000Z

    Time-resolved fluorescence spectra for colloidal CdSe and CdSe/CdS core/shell quantum dots have been investigated to know their electron relaxation dynamics at the maximum steady state fluorescence intensity. CdSe core and CdSe/CdS type I core-shell materials with different shell (CdS) thicknesses have been synthesized using mercaptoacetic acid as a capping agent. Steady state absorption and emission studies confirmed successful synthesis of CdSe and CdSe/CdS core-shell quantum dots. The fluorescence shows a tri-exponential decay with lifetimes 57.39, 7.82 and 0.96 ns for CdSe quantum dots. The lifetime of each recombination decreased with growth of CdS shell over the CdSe core, with maximum contribution to fluorescence by the fastest transition.

  6. Twinning effect on photoluminescence spectra of ZnSe nanowires

    SciTech Connect (OSTI)

    Xu, Jing; Wang, Chunrui, E-mail: crwang@dhu.edu.cn; Wu, Binhe; Xu, Xiaofeng [Department of Applied Physics and State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 Renmin Rd. North, Songjiang District, Shanghai 201620 (China); Chen, Xiaoshuang [Department of Applied Physics and State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 Renmin Rd. North, Songjiang District, Shanghai 201620 (China); National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai 200083 (China); Oh, Hongseok; Baek, Hyeonjun; Yi, Gyu-Chul [Department of Physics and Astronomy, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-747 (Korea, Republic of)

    2014-11-07T23:59:59.000Z

    Bandgap engineering in a single material along the axial length of nanowires may be realized by arranging periodic twinning, whose twin plane is vertical to the axial length of nanowires. In this paper, we report the effect of twin on photoluminescence of ZnSe nanowires, which refers to the bandgap of it. The exciton-related emission peaks of transverse twinning ZnSe nanowires manifest a 10-meV-blue-shift in comparison with those of longitudinal twinning ZnSe nanowires. The blue-shift is attributed to quantum confinement effect, which is influenced severely by the proportion of wurtzite ZnSe layers in ZnSe nanowires.

  7. Spectral photoresponse of ZnSe/GaAs(001) heterostructures with CdSe ultra-thin quantum well insertions

    SciTech Connect (OSTI)

    Valverde-Chávez, D. A.; Sutara, F.; Hernández-Calderón, I. [Physics Department, Cinvestav-IPN, Av. IPN 2508, 07360 México, DF (Mexico)

    2014-05-15T23:59:59.000Z

    We present a study of the spectral photoresponse (SPR) of ZnSe/GaAs(001) heterostructures for different ZnSe film thickness with and without CdSe ultra-thin quantum well (UTQW) insertions. We observe a significant increase of the SPR of heterostructures containing 3 monolayer thick CdSe UTQW insertions; these results encourage their use in photodetectors and solar cells.

  8. Antiferromagnetic Kondo lattice in the layered compound CePd1–xBi? and comparison to the superconductor LaPd1–xBi?

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

    Han, Fei; Wan, Xiangang; Phelan, Daniel; Stoumpos, Constantinos C.; Sturza, Mihai; Malliakas, Christos D.; Li, Qing'an; Han, Tian-Heng; Zhao, Qingbiao; Chung, Duck Young; et al

    2015-07-01T23:59:59.000Z

    The layered compound CePd1–xBi? with the tetragonal ZrCuSi?-type structure was obtained from excess Bi flux. Magnetic susceptibility data of CePd1–xBi? show an antiferromagnetic ordering below 6 K and are anisotropic along the c axis and the ab plane. The anisotropy is attributed to crystal-electric-field (CEF) effects and a CEF model which is able to describe the susceptibility data is given. An enhanced Sommerfeld coefficient ? of 0.191 J mol Ce?ą K?˛ obtained from specific-heat measurement suggests a moderate Kondo effect in CePd1–xBi?. Other than the antiferromagnetic peak at 6 K, the resistivity curve shows a shoulderlike behavior around 75 Kmore »which could be attributed to the interplay between Kondo and CEF effects. Magnetoresistance and Hall-effect measurements suggest that the interplay reconstructs the Fermi-surface topology of CePd1–xBi? around 75 K. Electronic structure calculations reveal that the Pd vacancies are important to the magnetic structure and enhance the CEF effects which quench the orbital moment of Ce at low temperatures.« less

  9. Bubble formation within filaments of melt-processed Bi2212 wires and its strongly negative effect on the critical current density

    E-Print Network [OSTI]

    the Jc of Bi2212 round wires. 1. Introduction The high-temperature superconductor (HTS) Bi2Sr2CaCu2Ox (BiBubble formation within filaments of melt-processed Bi2212 wires and its strongly negative effect.1088/0953-2048/24/7/075009 Bubble formation within filaments of melt-processed Bi2212 wires and its strongly negative effect

  10. Use and Finance BiAnnual Reporting Form Reporting Period: July 2013 through December 2013

    E-Print Network [OSTI]

    Papalambros, Panos

    Use and Finance BiAnnual Reporting Form Reporting Period: July 2013 through December 2013 $ Other (Professional Fees, Telecommunications, Moving) 538,200$ Other (Finance resources services center will be established for finance and human resources transaction processing activities

  11. Genetic approaches to studying coronary heart disease in SR-BI/apoE double knockout mice

    E-Print Network [OSTI]

    Karackattu, Sharon Liz

    2006-01-01T23:59:59.000Z

    Coronary heart disease (CHD) is a major healthcare concern in both developed and developing nations. The principal cause of CHD is atherosclerosis, the buildup of fatty deposits in vessel walls. SR-BI/apoE double knockout ...

  12. Buckling analysis of singly curved shallow bi-layered arch under concentrated loading

    E-Print Network [OSTI]

    Sonawane, Mahesh

    2009-05-15T23:59:59.000Z

    viable alternative to conventional sandwich materials in applications where the functional requirements can be met without the second face sheet of the sandwich. For structural applications bi-layered materials are required to have oil canning...

  13. Cost Savings and Energy Reduction: Bi-Level Lighting Retrofits in Multifamily Buildings

    E-Print Network [OSTI]

    Ackley, J.

    2010-01-01T23:59:59.000Z

    Community Environmental Center implements Bi- Level Lighting fixtures as a component of cost-effective multifamily retrofits. These systems achieve substantial energy savings by automatically reducing lighting levels when common areas are unoccupied...

  14. Strain induced irreversible critical current degradation in highly dense Bi-2212 round wire

    E-Print Network [OSTI]

    Bjoerstad, R; Rikel, M.O.; Ballarino, A; Bottura, L; Jiang, J; Matras, M; Sugano, M; Hudspeth, J; Di Michiel, M; 10.1088/0953-2048/28/6/062002

    2015-01-01T23:59:59.000Z

    The strain induced critical current degradation of overpressure processed straight Bi 2212/Ag wires has been studied at 77 K in self-field. For the first time superconducting properties, lattice distortions, composite wire stress and strain have been measured simultaneously in a high energy synchrotron beamline. A permanent Ic degradation of 5% occurs when the wire strain exceeds 0.60%. At a wire strain of about 0.65% a drastic n value and Ic reduction occur, and the composite stress and the Bi-2212 lattice parameter reach a plateau, indicating Bi-2212 filament fracturing. The XRD measurements show that Bi-2212 exhibits linear elastic behaviour up to the irreversible strain limit.

  15. Development of Wind-and-React Bi-2212 Accelerator Magnet Technology

    SciTech Connect (OSTI)

    Godeke, A.; Cheng, D.; Dietderich, D. R.; English, C. D.; Felice, H.; Hannaford, C. R.; Prestemon, S. O.; Sabbi, G.; Scanlan, R. M.; Hikichi, Y.; Nishioka, J.; Hasegawa, T.

    2007-08-28T23:59:59.000Z

    We report on the progress in our R&D program, targeted to develop the technology for the application of Bi2Sr2CaCu2Ox (Bi-2212) in accelerator magnets. The program uses subscale coils, wound from insulated cables, to study suitable materials, heat treatment homogeneity, stability, and effects of magnetic field and thermal and electro-magnetic loads. We have addressed material and reaction related issues and report on the fabrication, heat treatment, and analysis of subscale Bi-2212 coils. Such coils can carry a current on the order of 5000 A and generate, in various support structures, magnetic fields from 2.6 to 9.9 T. Successful coils are therefore targeted towards a hybrid Nb3Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 for accelerator magnets, and open a new magnetic field realm, beyond what is achievable with Nb3Sn.

  16. Development of Wind-and-React Bi-2212 Accelerator MagnetTechnology

    SciTech Connect (OSTI)

    Godeke, A.; Cheng, D.; Dietderich, D.R.; English, C.D.; Felice,H.; Hannaford, C.R.; Prestemon, S.O.; Sabbi, G.; Scanlan, R.M.; Hikichi,Y.; Nishioka, J.; Hasegawa, T.

    2007-08-28T23:59:59.000Z

    We report on the progress in our R&D program, targetedto develop the technology for the application of Bi2Sr2CaCu2Ox (Bi-2212)in accelerator magnets. The program uses subscale coils, wound frominsulated cables, to study suitable materials, heat treatmenthomogeneity, stability, and effects ofmagnetic field and thermal andelectro-magnetic loads. We have addressed material and reaction relatedissues and report onthe fabrication, heat treatment, and analysis ofsubscale Bi-2212 coils. Such coils can carry a current on the order of5000 A and generate, in various support structures, magnetic fields from2.6 to 9.9 T. Successful coils are therefore targeted towards a hybridNb3Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 foraccelerator magnets, and open a new magnetic field realm, beyond what isachievable with Nb3Sn.

  17. Rational Synthesis of Ultrathin n-Type Bi2Te3 Nanowires with Enhanced Thermoelectric Properties

    E-Print Network [OSTI]

    Xu, Xianfan

    the nanowire powder through spark plasma sintering have been investigated. Compared to the current commercial n and a reproducible way. KEYWORDS: Bi2Te3, nanowires, thermoelectric, spark plasma sintering Thermoelectric materials

  18. acid bi-directionally modulates: Topics by E-print Network

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

    stated in English as "A reservoir contains a liquid, called water, of mass 0.001 kg and heat capacity 4 VanLehn, Kurt 37 A Language for Bi-Directional Tree Transformations...

  19. Debonding in bi-layer material systems under moisture effect : a multiscale approach

    E-Print Network [OSTI]

    Lau, Tak-bun, Denvid

    2012-01-01T23:59:59.000Z

    Bi-layer material systems are found in various engineering applications ranging from nano-scale components, such as thin films in circuit boards, to macro-scale structures such as adhesive bonding in aerospace and civil ...

  20. Thermoelectric transport of Se-rich Ag{sub 2}Se in normal phases and phase transitions

    SciTech Connect (OSTI)

    Mi, Wenlong; Lv, Yanhong [State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China); CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences,1295 Dingxi Road, Shanghai 200050 (China); University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049 (China); Qiu, Pengfei; Shi, Xun, E-mail: xshi@mail.sic.ac.cn, E-mail: cld@mail.sic.ac.cn; Chen, Lidong, E-mail: xshi@mail.sic.ac.cn, E-mail: cld@mail.sic.ac.cn [State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China); CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences,1295 Dingxi Road, Shanghai 200050 (China); Zhang, Tiansong [CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences,1295 Dingxi Road, Shanghai 200050 (China)

    2014-03-31T23:59:59.000Z

    Small amount of Se atoms are used to tune the carrier concentrations (n{sub H}) and electrical transport in Ag{sub 2}Se. Significant enhancements in power factor and thermoelectric figure of merit (zT) are observed in the compositions of Ag{sub 2}Se{sub 1.06} and Ag{sub 2}Se{sub 1.08}. The excessive Se atoms do not change the intrinsically electron-conducting character in Ag{sub 2}Se. The detailed analysis reveals the experiment optimum carrier concentration in Ag{sub 2}Se is around 5?×?10{sup 18}?cm{sup ?3}. We also investigate the temperature of maximum zT and the thermoelectric transport during the first order phase transitions using the recently developed measurement system.

  1. Glass formation and the third harmonic generation of Cu{sub 2}Se–GeSe{sub 2}–As{sub 2}Se{sub 3} glasses

    SciTech Connect (OSTI)

    Reshak, A. H., E-mail: maalidph@yahoo.co.uk [New Technologies-Research Centre, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia); Klymovych, O. S.; Zmiy, O. F. [Department of Inorganic and Physical Chemistry, Lesya Ukrainka Eastern European National University, Voli Av. 13, 43025 Lutsk (Ukraine); Myronchuk, G. L.; Zamuruyeva, O. V. [Department of Physics, Lesya Ukrainka Eastern European National University, Voli Av. 13, 43025 Lutsk (Ukraine); Alahmed, Z. A. [Department of Physics and Astronomy, King Saud University, Riyadh 11451 (Saudi Arabia); Chyský, J.; Bila, Jiri [Department of Instrumentation and Control Engineering, Faculty of Mechanical Engineering, CTU in Prague, Technicka 4, 166 07 Prague 6 (Czech Republic); Kamarudin, H. [Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia)

    2014-10-14T23:59:59.000Z

    We have performed the investigation of the nonlinear optical properties namely the third harmonic generation (THG) of the glass-formation region in the Cu{sub 2}Se–GeSe{sub 2}–As{sub 2}Se{sub 3} system. The samples were synthesized by direct single-temperature method from high-purity elementary substances. We have found that the value of disorder parameter ? depends on the composition of the glassy alloys. The measurements show that increasing the Cu{sub 2}Se concentration leads to increased slope of the absorption edge, which may be explained by the decrease of the height of random potential relief for the electrons in the tails of the state density which border the band edges. A very sharp increase in the THG at low temperature was observed. Significant enhancement in THG was obtained with decreasing the energy gap, which agreed well with the nonlinear optical susceptibilities obtained from other glasses.

  2. Ion firehose instability in plasmas with plasma particles described by product bi-kappa distributions

    SciTech Connect (OSTI)

    Santos, M. S. dos; Ziebell, L. F., E-mail: luiz.ziebell@ufrgs.br; Gaelzer, R., E-mail: rudi.gaelzer@ufrgs.br [Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, RS, CEP: 91501-970 Porto Alegre (Brazil)

    2014-11-15T23:59:59.000Z

    We investigate the dispersion relation for low frequency electromagnetic waves propagating parallel to the ambient magnetic field, considering that the velocity distributions of ions and electrons can be either bi-Maxwellian of product bi-kappa distributions. The effect of the anisotropy and non-thermal features associated to the product-bi-kappa distributions on the firehose instability are numerically investigated. The general conclusion to be drawn from the results obtained is that the increase in non-thermal features which is consequence of the decrease of the ? indexes in the ion distribution contributes to increase the instability in magnitude and wave number range, in comparison with bi-Maxwellian distributions with similar temperature anisotropy, and that the increase of non-thermal features in the electron distribution contributes to the quenching of the instability, which is nevertheless driven by the anisotropy in the ion distribution. Significant differences between results obtained either considering product-bi-kappa distributions or bi-kappa distributions are also reported.

  3. ammassalik island se: Topics by E-print Network

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

    Park Headquarters, Ventu- ra County, California. Conlee, Christina A 2000-01-01 26 infantil no se denuncia Multidisciplinary Databases and Resources Websites Summary:...

  4. Workshop on Revisions to SE 2004 Mark Ardis David Budgen

    E-Print Network [OSTI]

    Ardis, Mark

    Workshop on Revisions to SE 2004 Mark Ardis David Budgen Stevens Institute of Technology University-day workshop on needed revisions to Software Engineering 2004: Curriculum Guidelines for Undergraduate Degree Programs in Software Engineering (SE 2004). A brief overview of the current guidelines and their revision

  5. HA133F10SE1558 Final Report

    E-Print Network [OSTI]

    HA133F10SE1558 Final Report Trainable Video Analytic Software (HA133F10SE1558) October 20, 2010.4 Machine / Human Concepts 9 4.0 SeaUrchin Data 10 4.1 Halibut Detection Performance 12 4.1.1 Understanding) investigated the use of machine vision technology applied to electronic monitoring of the Rockfish fishery

  6. A 6-GHz Low-Power BiCMOS SiGe:C 0.25 m Direct Digital Synthesizer

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 A 6-GHz Low-Power BiCMOS SiGe:C 0.25 µm Direct Digital Synthesizer St´ephane Thuries, ´Eric SiGe direct digital synthesizer (DDS) is reported. This paper discusses the BiCMOS design differential pair. The circuit has been processed in a BiCMOS SiGe:C 0.25 µm technology. The power consumption

  7. SiGe BiCMOS for Analog, High-Speed Digital and Millimetre-Wave Applications Beyond 50 GHz

    E-Print Network [OSTI]

    Chan Carusone, Tony

    SiGe BiCMOS for Analog, High-Speed Digital and Millimetre-Wave Applications Beyond 50 GHz S -- This paper explores the application of SiGe BiCMOS technology to mm-wave transceivers with analog and digital signal processing. A review of 10- 80Gb/s SERDES performance across 3 SiGe BiCMOS and CMOS technology

  8. p1 RJM 07/01/14 SE3SE11 -Sustainable Electrical Energy -Gaia Dr Richard Mitchell 2014

    E-Print Network [OSTI]

    Mitchell, Richard

    p1 RJM 07/01/14 SE3SE11 - Sustainable Electrical Energy - Gaia © Dr Richard Mitchell 2014 1 : Sustainable Electrical Energy - Gaia This module considers the sustainable aspects of Electrical Energy For instance, various colleagues, including Dr George Whitfield, researched photovoltaic solar systems

  9. Optical Probing of metamagnetic phases in epitaxial EuSe

    SciTech Connect (OSTI)

    Galgano, G. D.; Henriques, A. B. [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970 Sao Paulo (Brazil); Bauer, G.; Springholz, G. [Institut fuer Halbleiter und Festkoerperphysik, Johannes Kepler Universitaet Linz, 4040 Linz (Austria)

    2011-12-23T23:59:59.000Z

    EuSe is a wide gap magnetic semiconductors with a potential for applications in proof-of-concept spintronic devices. When the temperature is lowered, EuSe goes through sharp transitions between a variety of magnetic phases and is thus described as metamagnetic. The purpose of the present investigation is to correlate the magnetic order to the sharp dichroic doublet, discovered recently in high quality thin epitaxial layers of EuSe, grown by molecular beam epitaxy. We report detailed measurements of the doublet positions and intensities as a function of magnetic field in low temperatures, covering several magnetic phases.

  10. Prospects of nanostructures Bi{sub 1-x}Sb{sub x} for thermoelectricity

    SciTech Connect (OSTI)

    Nikolaeva, Albina A., E-mail: A.Nikolaeva@nano.asm.md [Gitsu Institute of Electronic Engineering and Nanotechnologies, Academiei 3/3, MD-2028, Chisinau, Republic of Moldova (Moldova, Republic of); International Laboratory of High Magnetic Fields and Low Temperatures, Wroclaw (Poland); Konopko, Leonid A. [Gitsu Institute of Electronic Engineering and Nanotechnologies, Academiei 3/3, MD-2028, Chisinau, Republic of Moldova (Moldova, Republic of) [Gitsu Institute of Electronic Engineering and Nanotechnologies, Academiei 3/3, MD-2028, Chisinau, Republic of Moldova (Moldova, Republic of); International Laboratory of High Magnetic Fields and Low Temperatures, Wroclaw (Poland); Huber, Tito E. [Department of Chemistry, Howard University, 500 College St. N.W., DC 20059, Washington (United States)] [Department of Chemistry, Howard University, 500 College St. N.W., DC 20059, Washington (United States); Bodiul, Pavel P.; Popov, Ivan A. [Gitsu Institute of Electronic Engineering and Nanotechnologies, Academiei 3/3, MD-2028, Chisinau, Republic of Moldova (Moldova, Republic of)] [Gitsu Institute of Electronic Engineering and Nanotechnologies, Academiei 3/3, MD-2028, Chisinau, Republic of Moldova (Moldova, Republic of)

    2012-09-15T23:59:59.000Z

    It has been predicted that surface states of topological insulators have large a thermopower and also ultrahigh mobilities. The authors report results of a magneto-thermoelectric investigation of single crystal Bi{sub 1-x}Sb{sub x} nanowires in a glass cover with diameters ranging from 90 nm to 5 {mu}m. The wide-ranging antimony concentration enabled us to study the effect of nanowire dimensionality in the semimetal, semi-conductor and gapless regimes. Quantum size effects in Bi-2 at%Sb nanowires, which are shown in temperature dependences of resistance R(T) and thermopower {alpha}(T) for the diameters significantly higher than the critical diameter for pure Bi-wires, are observed. The thermopower in weak magnetic fields, reaches values +400 {mu}V/K at T=20-40 K. Power factor {alpha}{sup 2}{sigma} depending on diameter of wires, structure, temperature and magnetic field is calculated. In connection with topological insulators, we will discuss the surface effect in the thermoelectric properties that we observe. - Graphical abstract: Temperature dependences of resistance R{sub T}/R{sub 300}(T) (a) for Bi-2 at%Sb wires various diameters d: 1-d=300 nm, 2-d=400 nm, 3-d=600 nm, 4-d=1600 nm. Inset (a) SEM cross sectional image of the 650 nm Bi-2 at%Sb wire (clear) in glass envelope (gray). The magnetic field dependences thermopower (H Double-Vertical-Line {Delta}T) (b) Bi-2 at%Sb wires, with different diameters: (1). d=300 nm, (2). d=400 nm, (3). d=600 nm, T=26 K. Highlights: Black-Right-Pointing-Pointer SMSC transition in semimetal Bi-Sb wires due to the quantum size effect is observed. Black-Right-Pointing-Pointer In Bi-6 at%Sb wires alloys has been realized the gapless (GL) state. Black-Right-Pointing-Pointer In the area GS state abnormal growth thermopower in magnetic fields is found out. Black-Right-Pointing-Pointer Semiconductor Bi{sub 1-x} Sb{sub x} nanowires manifest properties of the topological insulators.

  11. Human papillomavirus 16 E5 induces bi-nucleated cell formation by cell-cell fusion

    SciTech Connect (OSTI)

    Hu Lulin; Plafker, Kendra [Department of Cell Biology, University of Oklahoma (United States); Vorozhko, Valeriya [Department of Cell Biology, University of Oklahoma (United States); Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation (United States); Zuna, Rosemary E. [Department of Pathology, University of Oklahoma HSC (United States); Hanigan, Marie H. [Department of Cell Biology, University of Oklahoma (United States); Gorbsky, Gary J. [Department of Cell Biology, University of Oklahoma (United States); Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation (United States); Plafker, Scott M. [Department of Cell Biology, University of Oklahoma (United States); Angeletti, Peter C. [Nebraska Center for Virology (United States); Ceresa, Brian P. [Department of Cell Biology, University of Oklahoma (United States)], E-mail: brian-ceresa@oushc.edu

    2009-02-05T23:59:59.000Z

    Human papillomaviruses (HPV) 16 is a DNA virus encoding three oncogenes - E5, E6, and E7. The E6 and E7 proteins have well-established roles as inhibitors of tumor suppression, but the contribution of E5 to malignant transformation is controversial. Using spontaneously immortalized human keratinocytes (HaCaT cells), we demonstrate that expression of HPV16 E5 is necessary and sufficient for the formation of bi-nucleated cells, a common characteristic of precancerous cervical lesions. Expression of E5 from non-carcinogenic HPV6b does not produce bi-nucleate cells. Video microscopy and biochemical analyses reveal that bi-nucleates arise through cell-cell fusion. Although most E5-induced bi-nucleates fail to propagate, co-expression of HPV16 E6/E7 enhances the proliferation of these cells. Expression of HPV16 E6/E7 also increases bi-nucleated cell colony formation. These findings identify a new role for HPV16 E5 and support a model in which complementary roles of the HPV16 oncogenes lead to the induction of carcinogenesis.

  12. Controlled synthesis of T-shaped BiVO{sub 4} and enhanced visible light responsive photocatalytic activity

    SciTech Connect (OSTI)

    Dong, Shuying; Yu, Chongfei; Li, Yukun [School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007 (China); Li, Yihui [School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007 (China); Sun, Jianhui, E-mail: sunjh@htu.cn [School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007 (China); Geng, Xiaofei [School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007 (China)

    2014-03-15T23:59:59.000Z

    A novel T-shaped BiVO{sub 4} microcrystal photocatalyst was successfully synthesized by the hydrothermal method with the aid of a structure-directing surfactant SDBS in the present study. Having received well characterization with the aid of various techniques and the results showed that the SDBS greatly changed the microstructure of BiVO{sub 4}, which had a unique T shape and belonged to the monoclinic family. The fast exchange dynamics between the surfactants bound to the Bi{sup 3+} seed surface and the free VO{sub 3}{sup ?} in the solution significantly increase the rate of heterogeneous nucleation. In addition, the photocatalytic activity of the prepared T-shaped BiVO{sub 4} was evaluated by the degradation of Methylene Blue solution under visible light irradiation, 17% and 47% higher decolorization rates than the commercial P25 and BiVO{sub 4} synthesized without SDBS, respectively. Meanwhile, it has been found that the degradation kinetics of MB fitted the pseudo-first-order kinetics and the T-shaped BiVO{sub 4} also displayed high photocatalytic performance for metronidazole degradation. -- Graphical abstract: H{sub 2}O{sub 2} molecules function as electron trapping reagent to react with e{sup ?} to enhance the photocatalytic degradation efficiency of MB in the BiVO{sub 4}/H{sub 2}O{sub 2} system under visible light irradiation. Highlights: • T-shaped BiVO{sub 4} was synthesized using SDBS as a structure-directing surfactant. • SDBS greatly changed the microstructure of BiVO{sub 4}. • The T-shaped BiVO{sub 4} had a better visible-light photocatalytic activity. • Degradation kinetics of MB by BiVO{sub 4} fitted the pseudo-first-order kinetics.

  13. Hot exciton transport in ZnSe quantum wells

    E-Print Network [OSTI]

    Zhao, Hui; Moehl, Sebastian; Wachter, Sven; Kalt, Heinz

    2002-02-01T23:59:59.000Z

    The in-plane transport of excitons in ZnSe quantum wells is investigated directly by microphotoluminescence in combination with a solid immersion lens. Due to the strong Froehlich coupling, the initial kinetic energy of the excitons is well...

  14. Campus Security Report 1 Campus seCurity

    E-Print Network [OSTI]

    Wilmers, Chris

    Campus Security Report 1 Campus seCurity and Fire saFety report UC Santa Cruz 2010 #12;Campus Security Report 2 UC Santa Cruz Geography ........................................................ 8 Security and Access to Campus Buildings and Grounds ........................................ 8

  15. Inkrafttreten Diese Ordnung tritt mit Genehmigung durch die Se-

    E-Print Network [OSTI]

    Hoffmeister, Thomas S.

    § 7 Inkrafttreten Diese Ordnung tritt mit Genehmigung durch die Se- natorin für Bildung und. Artikel 2 Die �nderung tritt nach der Genehmigung des Rek- tors mit Wirkung vom 1. Oktober 2007 in Kraft

  16. Quantum size effects and transport phenomena in PbSe quantum wells and PbSe/EuS superlattices

    SciTech Connect (OSTI)

    Rogacheva, E. I.; Nashchekina, O. N.; Ol'khovskaya, S. I.; Sipatov, A. Yu. [National technical university Kharkov polytechnic institute, 21 Frunze St., Kharkov, 61002 (Ukraine); Dresselhaus, M. S. [Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge MA 02139 (United States)

    2013-12-04T23:59:59.000Z

    It is established that the room-temperature dependences of transport properties on the total thickness of PbSe layers d in PbSe/EuS superlattices exhibit an oscillatory behavior. It is shown that the oscillation period ?d practically coincides with the period of the thickness oscillations observed earlier in single PbSe/EuS quantum well. The non-monotonic character of these dependences is attributed to quantum size effects. The theoretically estimated and experimentally determined ?d values are in good agreement.

  17. Laser Ranging Delay in the Bi-Metric Theory of Gravity

    E-Print Network [OSTI]

    Sergei M. Kopeikin; Wei-Tou Ni

    2006-03-02T23:59:59.000Z

    We introduce a linearized bi-metric theory of gravity with two metrics. The metric g_{ab} describes null hypersurfaces of the gravitational field while light moves on null hypersurfaces of the optical metric \\bar{g}_{ab}. Bi-metrism naturally arises in vector-tensor theories with matter being non-minimally coupled to gravity via long-range vector field. We derive explicit Lorentz-invariant solution for a light ray propagating in space-time of the bi-metric theory and disentangle relativistic effects associated with the two metrics. This anlysis can be valuable for future spaceborne laser missions ASTROD and LATOR dedicated to map various relativistic gravity parameters in the solar system to unparalleled degree of accuracy.

  18. Experimental Realization of a Three-Dimensional Topological Insulator, Bi 2Te3

    SciTech Connect (OSTI)

    Siemons, W.

    2010-02-24T23:59:59.000Z

    Three-dimensional topological insulators are a new state of quantum matter with a bulk gap and odd number of relativistic Dirac fermions on the surface. By investigating the surface state of Bi{sub 2}Te{sub 3} with angle-resolved photoemission spectroscopy, we demonstrate that the surface state consists of a single nondegenerate Dirac cone. Furthermore, with appropriate hole doping, the Fermi level can be tuned to intersect only the surface states, indicating a full energy gap for the bulk states. Our results establish that Bi{sub 2}Te{sub 3} is a simple model system for the three-dimensional topological insulator with a single Dirac cone on the surface. The large bulk gap of Bi{sub 2}Te{sub 3} also points to promising potential for high-temperature spintronics applications.

  19. First-Principles Study of Surface States of Bi{sub 2}Te{sub 3}

    SciTech Connect (OSTI)

    Park, Kyungwha [Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2011-12-26T23:59:59.000Z

    Bi{sub 2}Te{sub 3} is a topological insulator with time reversal symmetry possessing a single Dirac cone at a given surface. The surface states of topological insulators play a critical role in exotic physical phenomena and their applications. We investigate the surface states of thin films of Bi{sub 2}Te{sub 3}(111) using density-functional theory including spin-orbit coupling. Considering one to six quintuple layers (QLs) of Bi{sub 2}Te{sub 3} films, we identify the surface states from calculated band structures using the decay length of the surface states and electron density plots. We show that the films of 1 and 2 QLs are too thin to hold the surface states protected topologically, and that for thicker films bands identified as surface states at {Gamma}-bar lose their surface-state features away from {Gamma}-bar. This method can be applied to other topological insulators.

  20. Structural and dielectric properties of Nd/Ca co-doped bi-ferrite multiferroics

    SciTech Connect (OSTI)

    Kumar, Ashwini, E-mail: vdinesh33@rediffmail.com, E-mail: ashu.dhanda@gmail.com; Sharma, Poorva, E-mail: vdinesh33@rediffmail.com, E-mail: ashu.dhanda@gmail.com; Varshney, Dinesh, E-mail: vdinesh33@rediffmail.com, E-mail: ashu.dhanda@gmail.com [School of Physics, Vigyan Bhawan, Devi Ahilya University, Khandwa Road Campus, Indore 452001 (India)

    2014-04-24T23:59:59.000Z

    Single-phase polycrystalline samples of Bi{sub 0.8}Nd{sub 0.2?x}Ca{sub x}FeO{sub 3} (x = 0.0, 0.1) were synthesized by chemical coprecipitation method. X-ray diffraction patterns accompanied by Rietveld-refined crystal structure parameters reveal the phase transition of Bi{sub 0.8}Nd{sub 0.1}Ca{sub 0.1}FeO{sub 3} with rhombohedral R3c symmetry to triclinic structure of Bi{sub 0.8}Nd{sub 0.2}FeO{sub 3} sample. Frequency dependence of dielectric constant (?') and dielectric loss (tan?), infers enhancement of both ?' (tan?) in narrow band gap of Nd/Ca co-doped BFO as compare to wide band pristine BFO.

  1. Quasi-two-dimensional Dirac fermions and quantum magnetoresistance in LaAgBi2

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

    Wang, Kefeng; Graf, D.; Petrovic, C.

    2013-06-01T23:59:59.000Z

    We report quasi-two-dimensional (2D) Dirac fermions and quantum magnetoresistance in LaAgBi2. The band structure shows several narrow bands with nearly linear energy dispersion and Dirac-cone-like points at the Fermi level. The quantum oscillation experiments revealed one quasi-two-dimensional Fermi pocket and another complex pocket with a small cyclotron resonant mass. The in-plane transverse magnetoresistance exhibits a crossover at a critical field B? from semiclassical weak-field B2 dependence to the high-field unsaturated linear magnetoresistance which is attributed to the quantum limit of the Dirac fermions. Our results suggest the existence of quasi-2D Dirac fermions in rare-earth-based layered compounds with two-dimensional double-sized Bi square nets, similar to (Ca,Sr)MnBi2, irrespective of magnetic order.

  2. Superconductivity at 34 K in the K/Ba/Bi/O system

    SciTech Connect (OSTI)

    Jones, N.L.; Parise, J.B.; Flippen, R.B.; Sleight, A.W. (E.I. DuPont de Nemours and Co., Wilmington, DE (USA))

    1989-02-01T23:59:59.000Z

    The critical temperature for superconductivity in the (Ba, K)BiO{sub 3} system has been increased to 34 K. With each such increase of T{sub c} in a system containing no copper it becomes increasingly likely that the mechanisms for superconductivity in the Bi-based and the Cu-based oxide superconductors are very closely related to each other. Since the (Ba, K)BiO{sub 3} superconductors possess the cubic perovskite structure, the mechanism for high T{sub c} would then not related directly to the two-dimensional character of the copper oxide superconductors or to the magnetism in such systems. 12 refs., 1 fig.

  3. Ferromagnetism and the electronic band structure in (Ga,Mn)(Bi,As) epitaxial layers

    SciTech Connect (OSTI)

    Yastrubchak, O., E-mail: yastrub@hektor.umcs.lublin.pl [Institute of Physics, Maria Curie-Sklodowska University in Lublin, Pl. M. Curie-Sk?odowskiej 1, 20-031 Lublin (Poland); Institute of Semiconductor Physics, National Academy of Sciences, 41 pr. Nauki, 03028 Kyiv (Ukraine); Sadowski, J. [MAX-IV Laboratory, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden); Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Gluba, L.; ?uk, J.; Kulik, M. [Institute of Physics, Maria Curie-Sklodowska University in Lublin, Pl. M. Curie-Sk?odowskiej 1, 20-031 Lublin (Poland); Domagala, J. Z.; Andrearczyk, T.; Wosinski, T. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Rawski, M. [Analytical Laboratory, Maria Curie-Sklodowska University in Lublin, Pl. M. Curie-Sk?odowskiej 3, 20-031 Lublin (Poland)

    2014-08-18T23:59:59.000Z

    Impact of Bi incorporation into (Ga,Mn)As layers on their electronic- and band-structures as well as their magnetic and structural properties has been studied. Homogenous (Ga,Mn)(Bi,As) layers of high structural perfection have been grown by the low-temperature molecular-beam epitaxy technique. Post-growth annealing treatment of the layers results in an improvement of their structural and magnetic properties and an increase in the hole concentration in the layers. The modulation photoreflectance spectroscopy results are consistent with the valence-band model of hole-mediated ferromagnetism in the layers. This material combines the properties of (Ga,Mn)As and Ga(Bi,As) ternary compounds and offers the possibility of tuning its electrical and magnetic properties by controlling the alloy composition.

  4. On the Design and Implementation of Transmission Lines in Commercial SiGe HBT BiCMOS Processes

    E-Print Network [OSTI]

    Papapolymerou, Ioannis "John"

    On the Design and Implementation of Transmission Lines in Commercial SiGe HBT BiCMOS Processes Matt the feasibility of implement- ing transmission lines in a commercially-available SiGe HBT BiCMOS technology. Thin film microstrip transmission lines using the top and bottom metalization layers (with a 3.24 ¡ m

  5. SiGe BiCMOS Topologies for Low-Voltage Millimeter-Wave Voltage Controlled Oscillators and Frequency Dividers

    E-Print Network [OSTI]

    Voinigescu, Sorin Petre

    SiGe BiCMOS Topologies for Low-Voltage Millimeter-Wave Voltage Controlled Oscillators and Frequency-mail: tod@eecg.toronto.edu Abstract -- BiCMOS topologies for mm-wave voltage- controlled oscillators operation for mm-wave applications. II. BICMOS VOLTAGE-CONTROLLED OSCILLATOR The Colpitts topology

  6. Mechanically-exfoliated stacks of thin films of Bi2Te3 topological insulators with enhanced thermoelectric performance

    E-Print Network [OSTI]

    Mechanically-exfoliated stacks of thin films of Bi2Te3 topological insulators with enhanced; published online 1 October 2010 The authors report on "graphene-like" mechanical exfoliation of single can be used to mechanically exfoliate the ultrathin films of Bi2Te3 with the thickness down

  7. Impedance Matching Wilkinson Power Dividers in 0.35m SiGe BiCMOS Technology

    E-Print Network [OSTI]

    Yanikoglu, Berrin

    1 Impedance Matching Wilkinson Power Dividers in 0.35µm SiGe BiCMOS Technology Ercan Kaymaksut miniature Impedance Matching Wilkinson Power Divider circuits in 0.35µm SiGe BiCMOS technology for on

  8. Business Intelligence (BI) Developer Computer Methods International Corp. (CMiC) is a software Development firm specializing in

    E-Print Network [OSTI]

    Ellis, Randy

    Business Intelligence (BI) Developer Computer Methods International Corp. (CMiC) is a software Intelligence modules relating to Jaspersoft within our application. This position reports directly to the Manager of the Reports & BI Group. Duties and responsibilities (may include, but are not limited to

  9. Shubnikov-de Haas Oscillations in the Bulk Rashba Semiconductor BiTeI

    SciTech Connect (OSTI)

    Bell, C.; Bahramy, M.S.; Murakawa, H.; Checkelsky, J.G.; Arita, R.; Kaneko, Y.; Onose, Y.; Nagaosa, N.; Tokura, Y.; Hwang, H.Y.

    2012-07-11T23:59:59.000Z

    Bulk magnetoresistance quantum oscillations are observed in high quality single crystal samples of BiTeI. This compound shows an extremely large internal spin-orbit coupling, associated with the polarity of the alternating Bi, Te, and I layers perpendicular to the c-axis. The corresponding areas of the inner and outer Fermi surfaces around the A-point show good agreement with theoretical calculations, demonstrating that the intrinsic bulk Rashba-type splitting is nearly 360 meV, comparable to the largest spin-orbit coupling generated in heterostructures and at surfaces.

  10. Unique nanostructures and enhanced thermoelectric performance of melt-spun BiSbTe alloys

    SciTech Connect (OSTI)

    Xie Wenjie [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634-0978 (United States); Tang Xinfeng; Yan Yonggao; Zhang Qingjie [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Tritt, Terry M. [Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634-0978 (United States)

    2009-03-09T23:59:59.000Z

    We report a melt spinning technique followed by a quick spark plasma sintering procedure to fabricate high-performance p-type Bi{sub 0.52}Sb{sub 1.48}Te{sub 3} bulk material with unique microstructures. The microstructures consist of nanocrystalline domains embedded in amorphous matrix and 5-15 nm nanocrystals with coherent grain boundary. The significantly reduced thermal conductivity leads to a state-of-the-art dimensionless figure of merit ZT{approx}1.56 at 300 K, more than 50% improvement of that of the commercial Bi{sub 2}Te{sub 3} ingot materials.

  11. Development of Bi-Sb-Te ternary alloy with compositionally graded structure

    SciTech Connect (OSTI)

    Yamamoto, A.; Ohta, T.

    1997-07-01T23:59:59.000Z

    Compositionally graded p-type Bi-Sb-Te thermoelectric material was synthesized by PIES (Pulverized and Intermixed Elements Sintering) method. The materials consisted of three segmented regions of different alloy composition, i.e., y = 0.8/0.825/0.9 in (Bi{sub 2}Te{sub 3}){sub 1{minus}y} (Sb{sub 2}Te{sub 3}){sub y} system. It was found that the electrical power output of the compositionally graded material was larger than that of the best single composition material when the temperature difference was the designed value.

  12. Synthesis of highly phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor

    DOE Patents [OSTI]

    Dorris, S.E.; Poeppel, R.B.; Prorok, B.C.; Lanagan, M.T.; Maroni, V.A.

    1994-10-11T23:59:59.000Z

    An article and method of manufacture of (Bi,Pb)-Sr-Ca-Cu-O superconductor are disclosed. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi,Pb)-Sr-Ca-Cu-O superconductor. 5 figs.

  13. Synthesis of highly phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor

    DOE Patents [OSTI]

    Dorris, Stephen E. (La Grange Park, IL); Poeppel, Roger B. (Glen Ellyn, IL); Prorok, Barton C. (Harrisville, PA); Lanagan, Michael T. (Woodridge, IL); Maroni, Victor A. (Naperville, IL)

    1994-01-01T23:59:59.000Z

    An article and method of manufacture of (Bi,Pb)-Sr-Ca-Cu-O superconductor. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi,Pb)-Sr-Ca-Cu-O superconductor.

  14. 520 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 18, NO. 2, JUNE 2008 Electromechanical Behavior of Bi2Sr2CaCu2Ox

    E-Print Network [OSTI]

    strain margin. Recent coils with Bi2212 round wire have used W&R [9]. The coil is wound when conductor, and the magnet is wound between these heat treatments. Here we report results on the RWS "split melt process decomposition tem- perature of the Bi2212 phase and slowly cooling down to form a well-connected and aligned Bi

  15. MINIREVIEW / MINISYNTHE` SE The role of chromatin structure in regulating

    E-Print Network [OSTI]

    Krebs, Jocelyn E.

    within many stress-induced promoters, such as stress re- sponse elements and heat shock elements, allow. Key words: chromatin, transcription, stress response, heat shock. Re´sume´ : Toutes les cellules, quMINIREVIEW / MINISYNTHE` SE The role of chromatin structure in regulating stress

  16. se de doctorat en informatique Comprendre le Web cach

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    niveau à l'aide de telles descriptions. Abstract e hidden Web (also known as deep or invisible Web'informations, complexité Keywords: hidden Web, deep Web, databases, information extraction, complexity tel-00198150,versionèse de doctorat en informatique Comprendre le Web caché Understanding the Hidden Web Pierre

  17. EXTERIOR POWERS OF SYMMETRIC BILINEAR FORMS SE'AN MCGARRAGHY

    E-Print Network [OSTI]

    -fold exterior power of V . Then the ring of* * isomorphism classes of finite-dimensional K-vector spaces under]. 3. Exterior and symmetric powers of symmetric bilinear forms Let V be a vector space of dimension EXTERIOR POWERS OF SYMMETRIC BILINEAR FORMS SE

  18. SeRLoc: Robust Localization for Wireless Sensor Networks

    E-Print Network [OSTI]

    Hochberg, Michael

    SeRLoc: Robust Localization for Wireless Sensor Networks LOUKAS LAZOS and RADHA POOVENDRAN University of Washington Many distributed monitoring applications of Wireless Sensor Networks (WSNs) require of Wireless Sensor Networks to determine their location in an untrusted environment, known as the secure

  19. Structural Changes in Vitreous GeSe4 under Pressure

    SciTech Connect (OSTI)

    Skinner L. B.; Parise J.; Benmore, C.J,; Antao, S.; Soignard, E.; Amin, S.A.; Bychkov, E.; Rissi, E. and Yarger, J.L.

    2011-11-21T23:59:59.000Z

    High-energy X-ray diffraction experiments have been performed on GeSe{sub 4} glass up to pressures of 8.6 GPa, and the equation of state has been measured up to 10 GPa. The X-ray structure factors reveal a decrease in the first sharp diffraction peak intensity and broadening with pressure, which signifies a break-up of the intermediate range order in the glass. In contrast, the principal peak in the structure factor shows an increase in intensity and a sharpening with pressure, which is attributed to an increase in extended range order and coherence of the compacted units. The average nearest neighbor coordination number is found to remain constant in GeSe{sub 4} glass (within experimental error) over the pressure range measured. This is in contrast with the gradual increase found in GeSe{sub 2} glass. Rather, in GeSe{sub 4} glass the densification mechanism is shown to be associated with large inward shifts of the second neighbor and higher coordination shells. These features appear as additional correlations at 3.3 and 5.3 {angstrom} in the differences taken between adjacent pair distribution functions with increasing pressure.

  20. con Diabetes Su diabetes s se puede controlar!

    E-Print Network [OSTI]

    Do Well, Be Well con Diabetes ˇSu diabetes sí se puede controlar! Educational programs of the Texas, and the County Commissioners Courts of Texas Cooperating. to develop diabetes self-care skills, to improve eating habits and maintain good nutrition, to increase physical activity, to prevent diabetes complications

  1. KTH Aeronautical and Vehicle Engineering, Teknikringen 8, SE-10044 Stockholm. Phone: +46 70 6522441. E-mail: mabe@kth.se Pg: 1 56 53-9. Bg: 895-9223. VAT: SE202100305401. www.kth.se

    E-Print Network [OSTI]

    Haviland, David

    KTH Aeronautical and Vehicle Engineering, Teknikringen 8, SE-10044 Stockholm. Phone: +46 70 6522441 on Energy Usage of Tracked Taxis Car-like vehicles running on elevated guideways in urban areas or airports vehicles and traditional vehicles, including both measurements and simulations. - Study the rolling

  2. Research into the microstructure and mechanical behavior of eutectic Bi-Sn and In-Sn

    SciTech Connect (OSTI)

    Goldstein, J.L.F.; Mei, Z.; Morris, J.W. Jr. [Lawrence Berkeley Lab., CA (United States)]|[California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering

    1993-08-01T23:59:59.000Z

    This manuscript reports on research into two low-melting, lead-free solder alloys, eutectic Bi-Sn and eutectic In-Sn. The microstructures were found to depend on both cooling rate and substrate, with the greatest variability in the In-Sn alloy. The nature of the intermetallic layer formed at the solder-substrate interface depends on both the solder and the substrate (Cu versus Ni). Also, the microstructure of the Bi-Sn can recrystallize during deformation, which is not the case with In-Sn. Data from creep and constant strain rate tests are given for slowly cooled samples. The creep behavior of In-Sn is constant with temperature, but the creep seems to be controlled by the In-rich phase in In-Sn on Cu and by the Sn-rich phase in In-Sn on Ni. Bi-Sn exhibits different creep behavior at temperatures above 40 {degrees}C than at 20 {degrees}C or lower. Stress-strain curves of Bi-Sn on Cu and In-Sn on Cu are similar, while In-Sn on Ni behaves differently. This is explained in terms of the deformation patterns in the alloys.

  3. Preparation of Bi-Sr-Ca-Cu-O superconductors from oxide-glass precursors

    DOE Patents [OSTI]

    Hinks, David G. (Lemont, IL); Capone, II, Donald W. (Northbridge, MA)

    1992-01-01T23:59:59.000Z

    A superconductor and precursor therefor from oxide mixtures of Ca, Sr, Bi and Cu. Glass precursors quenched to elevated temperatures result in glass free of crystalline precipitates having enhanced mechanical properties. Superconductors are formed from the glass precursors by heating in the presence of oxygen to a temperature below the melting point of the glass.

  4. CONFERENCE PROGRAM (as of October 4, 2012) WTERT 2012 Bi-Annual Conference at Columbia University

    E-Print Network [OSTI]

    Hone, James

    1 CONFERENCE PROGRAM (as of October 4, 2012) WTERT 2012 Bi-Annual Conference at Columbia University, Columbia University 9:10 AM Session 1: "WTE technology advances" - Session Chair: Mr. Ted Michaels Columbia University, NYC, October 18-19, 2012 2 11:25 AM Mr. John Foden, President, Canadian Energy from

  5. Grain refinement and texture development of cast bi90sb10 alloy via severe plastic deformation

    E-Print Network [OSTI]

    Im, Jae-taek

    2009-05-15T23:59:59.000Z

    The purpose of this work was to study learn about grain refinement mechanisms and texture development in cast n-type Bi90Sb10 alloy caused by severe plastic deformation. The practical objective is to produce a fine grained and textured...

  6. (Alpha, Beta)-Fuzzy Subsemigroup and (Alpha, Beta)-Fuzzy Bi-ideal in Gamma- Semigroups

    E-Print Network [OSTI]

    Sujit Kumar Sardar; Bijan Davvaz; Samit Kumar Majumder; Soumitra Kayal

    2011-02-01T23:59:59.000Z

    In this paper, using the idea of quasi-coincidence of a fuzzy point with a fuzzy set, the concepts of (epsilon, epsilon join q)- fuzzy subsemigroup and (epsilon, epsilon join q)- fuzzy bi-ideal in a gamma-semigroup have been introduced and some related properties have been investigated.

  7. Bi-content Gadolinia as Burnable Absorber in PWR to Improve the Reactor Core Behaviour

    SciTech Connect (OSTI)

    Zheng, S. [AREVA, AREVA NP Fuel Sector, 10, Rue Juliette Recamier 69456 Lyon cedex (France)

    2007-07-01T23:59:59.000Z

    The gadolinia product is one of the standard burnable absorbers used in the PWR long and low leakage fuel cycle in order to control the radial power distribution and to hold down the initial core reactivity. This product presents a large number of advantages such as the high efficiency with only a small number of gadolinia-bearing rods, the easy adjustment between the number and the content of the gadolinia-bearing rods according to the cycle length need and the initial reactivity hold-down, no increasing of boron concentration versus cycle depletion, no additional increasing of internal pressure in poisoned rods, very low additional manufacture cost. On the other hand, some unfavourable phenomena are also observed during the utilization of the gadolinia: amplification of the asymmetrical power distribution and more negative axial offset. Based on the correlation between the gadolinia burnout and its content, the use of gadolinia bi-content will improve the parameters indicated here above. The gadolinia bi-content have been used in BWR for more than 20 years. In this paper, the comparison of the main reactor core physical parameters in PWR, calculated with the AREVA NP standard neutronic code package SCIENCE, is made by using the mono- and bi-content of the gadolinia products in the same fuel assembly. The results show that the asymmetrical axial and azimuthal power distribution can be improved in the case of the bi-content gadolinia product. (authors)

  8. Reversal mechanisms of coupled bi-component magnetic nanostructures G. Shimon,1,2

    E-Print Network [OSTI]

    Adeyeye, Adekunle

    in applications such as high density information storage,1­3 domain wall (DW) logic,4,5 and memory devices.6Reversal mechanisms of coupled bi-component magnetic nanostructures G. Shimon,1,2 A. O. Adeyeye,1 Institute of Physics. [http://dx.doi.org/10.1063/1.4747446] Thin film ferromagnetic nanostructures have been

  9. A validation of a ray-tracing tool used to generate bi-directional scattering

    E-Print Network [OSTI]

    and daylighting technologies. Keywords: Daylighting; Solar Heat Gain; Complex fenestration systems; Bi in Solar Energy 98 (2013): 404-414 DOI: 10.1016/j.solener.2013.09.032 #12;DISCLAIMER This document, product, or process disclosed, or represents that its use would not infringe privately owned rights

  10. Eye-Tracker {eskim, jkim, btzhang} @ bi.snu.ac.kr

    E-Print Network [OSTI]

    Eye-Tracker ,, {eskim, jkim, btzhang} @ bi.snu.ac.kr Eye-Tracking Analysis of Attention . `' . . . Eye-Tracker . Eye-Tracker . . 1. , . `' , . . , . . , . 3 [1]. 1) fMRI, MEG, EEG 2) Eye-Tracker, Motion Tracker embodiment cognition 3

  11. SHORT COMMUNICATIONS 149 energetics of small birds. Journal of Thermal Bi-

    E-Print Network [OSTI]

    Richner, Heinz

    ­157. In C. Carey [ED.], Avian energetics and nutritional ecology. Chapman & Hall, New York. ROBINSON, D. ESHORT COMMUNICATIONS 149 energetics of small birds. Journal of Thermal Bi- ology 2. Thermoregulation and the energetic significance of clustering behavior in the White-backed Mousebird (Colius colius

  12. A SingleQuery BiDirectional Probabilistic Roadmap Planner with Lazy Collision Checking

    E-Print Network [OSTI]

    LaValle, Steven M.

    1 A Single­Query Bi­Directional Probabilistic Roadmap Planner with Lazy Collision Checking Gildardo probabilistic roadmap (PRM) planner that is: single­query --it does not pre­compute a roadmap, but uses the two the robot's free space by concurrently building a roadmap made of two trees rooted at the query

  13. Progress in Wind-and-React Bi-2212 Accelerator Magnet Technology

    SciTech Connect (OSTI)

    Godeke, A.; Cheng, D.; Dietderich, D.R.; Hannaford, C.R.; Prestemon, S.O.; Sabbi, G.; Wang, X.; Hikichi, Y.; Nishioka, J.; Hasegawa, T.

    2009-08-16T23:59:59.000Z

    We report on our progress in the development of the technology for the application of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+x}(Bi-2212) in Wind-and-React accelerator magnets. A series of superconducting subscale coils has been manufactured at LBNL and reacted at the wire manufacturer SWCC. Selected coils are impregnated and tested in self-field, even though the coils exhibited leakage during the partial melt heat treatment. Other coils have been disassembled after reaction and submitted to critical current (Ic) tests on individual cable sections. We report on the results of the current carrying capacity of the coils. Voltage-current (VI) transitions were reproducibly measured up to a quench currents around 1400 A, which is 25% of the expected performance. The results indicate that the coils are limited by the inner windings. We further compare possibilities to use Bi-2212 and Nb{sub 3}Sn tilted solenoid, and YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) racetrack inserts to increase the magnetic field in HD2, a 36 mm bore Nb{sub 3}Sn dipole magnet which recently achieved a bore magnetic field of 13.8 T. The application of Bi-2212 and/or YBCO in accelerator type magnets, if successful, will open the road to higher magnetic fields, far surpassing the limitations of Nb{sub 3}Sn magnet technology.

  14. WInd-and-react Bi-2212 coil development for accelerator magnets

    SciTech Connect (OSTI)

    Godeke, A.; Acosta, P.; Cheng, D.; Dietderich, D. R.; Mentink, M. G. T.; Prestemon, S. O.; Meinesz, M.; Hong, S.; Huang, Y.; Miao, H.; Parrell, J.; Sabbi, G.L.

    2009-10-13T23:59:59.000Z

    Sub-scale coils are being manufactured and tested at Lawrence Berkeley National Laboratory in order to develop wind-and-react Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (Bi-2212) magnet technology for future graded accelerator magnet use. Previous Bi-2212 coils showed significant leakage of the conductors core constituents to the environment, which can occur during the partial melt reaction around 890 C in pure oxygen. The main origin of the observed leakage is intrinsic leakage of the wires, and the issue is therefore being addressed at the wire manufacturing level. We report on further compatibility studies, and the performance of new sub-scale coils that were manufactured using improved conductors. These coils exhibit significantly reduced leakage, and carry currents that are about 70% of the witness wire critical current (I{sub c}). The coils demonstrate, for the first time, the feasibility of round wire Bi-2212 conductors for accelerator magnet technology use. Successful high temperature superconductor coil technology will enable the manufacture of graded accelerator magnets that can surpass the, already closely approached, intrinsic magnetic field limitations of Nb-based superconducting magnets.

  15. WInd-and-react Bi-2212 coil development for accelerator magnets

    E-Print Network [OSTI]

    Godeke, A.

    2011-01-01T23:59:59.000Z

    Figure 2. Coil HTS-SC08 and witness barrels and wires afterO S T Bi-2212 round wire. Coil ID HTS-SC02 HTS-SC04 HTS-SC06with the wires soldered to the barrels. c Coil ID HTS-SC04

  16. Development of Wind-and-React Bi-2212 Accelerator Magnet Technology

    SciTech Connect (OSTI)

    Cheng, Daniel; Dietderich, Daniel R.; English, C.D.; Felice, Helene; Hannaford, Charles R.; Prestemon, Soren O.; Sabbi, GianLuca; Scanlan, Ron M.; Hikichi, Y.; Nishioka, J.; Hasegawa, T.; Godeke, A.

    2007-06-01T23:59:59.000Z

    We report on the progress in our R&D program, targeted to develop the technology for the application of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (Bi-2212) in accelerator magnets. The program uses subscale coils, wound from insulated cables, to study suitable materials, heat treatment homogeneity, stability, and effects of magnetic field and thermal and electro-magnetic loads. We have addressed material and reaction related issues and report on the fabrication, heat treatment, and analysis of subscale Bi-2212 coils. Such coils can carry a current on the order of 5000 A and generate, in various support structures, magnetic fields from 2.6 to 9.9 T. Successful coils are therefore targeted towards a hybrid Nb{sub 3}Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 for accelerator magnets, and open a new magnetic field realm, beyond what is achievable with Nb{sub 3}Sn.

  17. Solar Energy 74 (2003) 157173 Comparison between ray-tracing simulations and bi-directional

    E-Print Network [OSTI]

    Solar Energy 74 (2003) 157­173 Comparison between ray-tracing simulations and bi-Louis Scartezzini a Solar Energy and Building Physics Laboratory LESO-PB, Swiss Federal Institute of Technology EPFL Cyclotron Road, MS 2-300, Berkeley, CA 94720-8134, USA Abstract Evaluation of solar heat gain and daylight

  18. BINGO: A code for the efficient computation of the scalar bi-spectrum

    E-Print Network [OSTI]

    Dhiraj Kumar Hazra; L. Sriramkumar; Jerome Martin

    2013-05-18T23:59:59.000Z

    We present a new and accurate Fortran code, the BI-spectra and Non-Gaussianity Operator (BINGO), for the efficient numerical computation of the scalar bi-spectrum and the non-Gaussianity parameter f_{NL} in single field inflationary models involving the canonical scalar field. The code can calculate all the different contributions to the bi-spectrum and the parameter f_{NL} for an arbitrary triangular configuration of the wavevectors. Focusing firstly on the equilateral limit, we illustrate the accuracy of BINGO by comparing the results from the code with the spectral dependence of the bi-spectrum expected in power law inflation. Then, considering an arbitrary triangular configuration, we contrast the numerical results with the analytical expression available in the slow roll limit, for, say, the case of the conventional quadratic potential. Considering a non-trivial scenario involving deviations from slow roll, we compare the results from the code with the analytical results that have recently been obtained in the case of the Starobinsky model in the equilateral limit. As an immediate application, we utilize BINGO to examine of the power of the non-Gaussianity parameter f_{NL} to discriminate between various inflationary models that admit departures from slow roll and lead to similar features in the scalar power spectrum. We close with a summary and discussion on the implications of the results we obtain.

  19. Variable mode bi-directional and uni-directional computer communication system

    DOE Patents [OSTI]

    Cornett, Frank N.; Jenkins, Philip N.; Bowman, Terrance L.; Placek, Joseph M.; Thorson, Gregory M.

    2004-12-14T23:59:59.000Z

    A variable communication systems comprising a plurality of transceivers and a control circuit connected to the transceivers to configure the transceivers to operate in a bi-directional mode and a uni-directional mode at different times using different transfer methods to transfer data.

  20. BiP Clustering Facilitates Protein Folding in the Endoplasmic Reticulum

    E-Print Network [OSTI]

    Petzold, Linda R.

    BiP Clustering Facilitates Protein Folding in the Endoplasmic Reticulum Marc Griesemer1. *, Carissa (ER): translocation, protein folding, and ER-associated degradation. To facilitate protein folding may enhance protein folding and maturation. Scenarios were simulated to gauge the effectiveness

  1. Therm-optic analysis of bi-metallic mirrors Daniel Vukobratovich and Allen Gerzoff

    E-Print Network [OSTI]

    plated with electroless nickel to reduce light scattering. The thermal coefficient of expansion of electroless nickel, 13.5 x 10-6 m/m-K, is significantly different from that of a typical mirror substrate in an electroless nickel plated mirror, which can induce optical surface distortion. Possible solutions to the "bi

  2. Using Process Mining to Bridge the Gap between BI and BPM

    E-Print Network [OSTI]

    van der Aalst, Wil

    offer mature data mining capabilities, and even the tools that do so, are not process-centric, i, and other data attributes (e.g., the size of an order). #12;Typically, three types of process mining canUsing Process Mining to Bridge the Gap between BI and BPM Wil van der Aalst Eindhoven University

  3. A model distribution function for relativistic bi-Maxwellian with drift

    SciTech Connect (OSTI)

    Naito, O. [Japan Atomic Energy Agency, 801-1 Mukouyama, Naka, Ibaraki 311-0193 (Japan)

    2013-04-15T23:59:59.000Z

    A model distribution function for relativistic bi-Maxwellian with drift is proposed, based on the maximum entropy principle and the relativistic canonical transformation. Since the obtained expression is compatible with the existing distribution functions and has a relatively simple form as well as smoothness, it might serve as a useful tool in the research fields of space or high temperature fusion plasmas.

  4. Postal address P.O. Box 118, SE-221 00 LUND Visiting address John Ericssons vg 3 Telephone switchboard +46 46-222 00 00 E-mail outgoing@kansli.lth.se Internet http://www.lth.se

    E-Print Network [OSTI]

    switchboard +46 46-222 00 00 E-mail outgoing@kansli.lth.se Internet http://www.lth.se International Office Telephone switchboard +46 46-222 00 00 E-mail outgoing@kansli.lth.se Internet http://www.lth.se ARGENTINA Sciences (Lahti Yrkeshögskola) Oulun yliopisto Tampereen Teknillinen Korkeakoulu University of Lapland

  5. Distinct superconducting states in the pressure-induced metallic structures of the nominal semimetal Bi[subscript 4]Te[subscript 3

    SciTech Connect (OSTI)

    Jeffries, J.R.; Sharma, A.L. Lima; Sharma, P.A.; Spataru, C.D.; McCall, S.K.; Sugar, J.D.; Weir, S.T.; Vohra, Y.K. (Sandia); (LLNL); (UAB)

    2011-11-07T23:59:59.000Z

    The end members, Bi and Bi{sub 2}Te{sub 3}, of the infinitely adaptive (Bi{sub 2})m(Bi{sub 2}Te{sub 3}){sub n} series of compounds have not only been revealed to be topological insulators under the appropriate conditions, but have also been shown to be superconductors under pressure, suggesting the potential for bulk superconductor-topological-insulator interfaces and associated quantum computing applications. Herein, we report the pressure-dependent evolution of the structure and electrical transport of the nominal semimetal Bi4Te{sub 3}, a member of the (Bi{sub 2})m(Bi{sub 2}Te{sub 3}){sub n} series. Under pressure, Bi4Te{sub 3} undergoes several structural phase transformations, ultimately yielding a metallic body-centered-cubic structure exhibiting superconductivity with a maximum T{sub c} = 8.4 K at 16.2 GPa. The occurrence of structure-dependent superconductivity in Bi{sub 4}Te{sub 3} is remarkably similar to the end members of the (Bi{sub 2})m(Bi{sub 2}Te{sub 3}){sub n} series, intimating a convergence to high-pressure universal behavior that may expose the subtle variations that lead to the topological insulating and superconducting states in these systems.

  6. Insulation and Heat Treatment of Bi-2212 Wire for Wind-and-React Coils

    SciTech Connect (OSTI)

    Peter K. F. Hwang

    2007-10-22T23:59:59.000Z

    Higher Field Magnets demand higher field materials such as Bi-2212 round superconducting wire. The Bi-2212 wire manufacture process depends on the coil fabrication method and wire insulation material. Considering the wind-and-react method, the coil must unifirmly heated to the melt temperature and uniformly cooled to the solidification temperature. During heat treat cycle for tightly wound coils, the leakage melt from conductor can chemically react with insulation on the conductor and creat short turns in the coils. In this research project, conductor, insulation, and coils are made to systemically study the suitable insulation materials, coil fabrication method, and heat treatment cycles. In this phase I study, 800 meters Bi-2212 wire with 3 different insulation materials have been produced. Best insulation material has been identified after testing six small coils for insulation integrity and critical current at 4.2 K. Four larger coils (2" dia) have been also made with Bi-2212 wrapped with best insulation and with different heattreatment cycle. These coils were tested for Ic in a 6T background field and at 4.2 K. The test result shows that Ic from 4 coils are very close to short samples (1 meter) result. It demonstrates that HTS coils can be made with Bi-2212 wire with best insulation consistently. Better wire insulation, improving coil winding technique, and wire manufacture process can be used for a wide range of high field magnet application including acclerators such as Muon Collider, fusion energy research, NMR spectroscopy, MRI, and other industrial magnets.

  7. Future use of BI-GAS facility. Final report, Part II. [Other possible uses

    SciTech Connect (OSTI)

    Not Available

    1981-09-01T23:59:59.000Z

    The 120 tpd BI-GAS pilot plant, intended to produce SNG at high pressure, was completed in 1976. For the next three and a half years, the operator, Stearns-Roger Inc., was engaged in operating the plant while overcoming a series of mechanical problems that have prevented the plant from running at design capacity and pressure. Since July 1980, these problems have apparently been corrected and considerable progress was made. In late 1979, the Yates Congressional Committee directed DOE to investigate the possibility of establishing an entrained-bed gasifier test facility at the site. In January 1981, the DOE established a study group composed of DOE and UOP/SDC personnel to determine how best to use the BI-GAS facility. The group considered four possibilities: Continue operation of the facility in accordance with the technical program plan developed by DOE and Stearns-Roger; modify the plant into an entrained-bed facility for testing components and processes; mothball the facility, or dismantle the facility. The group took the view that modifying the plant into a test facility would increase substantially the amount of engineering data available to the designers of commercial gasification plants. Since it appears that syngas plants will be of commercial interest sooner than SNG plants will, it was decided that the facility should test syngas production components and processes at high pressure. Consequently, it was recommended that: Operation of the plant be continued, both to collect data and to prove the BI-GAS process, as long as the schedule of the technical program plan is met; Begin at once to prepare a detailed design for modifying the BI-GAS plant to a high-pressure, entrained flow syngas test facility; and Implement the modification plan as soon as the BI-GAS process is proven or it becomes apparent that progress is unsatisfactory.

  8. Reverse Monte Carlo simulation of Se{sub 80}Te{sub 20} and Se{sub 80}Te{sub 15}Sb{sub 5} glasses

    SciTech Connect (OSTI)

    Abdel-Baset, A. M.; Rashad, M. [Physics Department, Faculty of Science , Assiut University, Assiut, P.O. Box 71516 (Egypt); Moharram, A. H. [Faculty of Science, King Abdul Aziz Univ., Rabigh Branch, P.O. Box 433 (Saudi Arabia)

    2013-12-16T23:59:59.000Z

    Two-dimensional Monte Carlo of the total pair distribution functions g(r) is determined for Se{sub 80}Te{sub 20} and Se{sub 80}Te{sub 15}Sb{sub 5} alloys, and then it used to assemble the three-dimensional atomic configurations using the reverse Monte Carlo simulation. The partial pair distribution functions g{sub ij}(r) indicate that the basic structure unit in the Se{sub 80}Te{sub 15}Sb{sub 5} glass is di-antimony tri-selenide units connected together through Se-Se and Se-Te chain. The structure of Se{sub 80}Te{sub 20} alloys is a chain of Se-Te and Se-Se in addition to some rings of Se atoms.

  9. APS/DPP 111207-se 1 University Fusion Association Meeting

    E-Print Network [OSTI]

    University Funding FY 2007-2008 ($ Millions) Program Element FY 2007 FY 2008 Sept Plan Oct Plan · C.0 · HEDLP 1.8 1.9 · Intl, Diagnostics, HBCU, Other 4.3 4.8 · Total University Funding 76.8 78.1 #12;APSAPS/DPP 111207-se 1 University Fusion Association Meeting Orlando, FL November 12, 2007 Stephen

  10. Temperature-dependent structural property and power factor of n type thermoelectric Bi{sub 0.90}Sb{sub 0.10} and Bi{sub 0.86}Sb{sub 0.14} alloys

    SciTech Connect (OSTI)

    Malik, K.; Das, Diptasikha [Department of Physics, University of Calcutta, 92 A P C Road, Kolkata 700 009 (India)] [Department of Physics, University of Calcutta, 92 A P C Road, Kolkata 700 009 (India); Bandyopadhyay, S.; Banerjee, Aritra, E-mail: arbphy@caluniv.ac.in [Department of Physics, University of Calcutta, 92 A P C Road, Kolkata 700 009 (India) [Department of Physics, University of Calcutta, 92 A P C Road, Kolkata 700 009 (India); Center for Research in Nanoscience and Nanotechnology, University of Calcutta, JD-2, Sector-III, Saltlake City, Kolkata 700 098 (India); Mandal, P.; Srihari, Velaga [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India)] [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India); Deb, A. K. [Department of Physics, Raiganj College (University College), Uttar Dinajpur 733 134 (India)] [Department of Physics, Raiganj College (University College), Uttar Dinajpur 733 134 (India)

    2013-12-09T23:59:59.000Z

    Thermal variation of structural property, linear thermal expansion coefficient (?), resistivity (?), thermopower (S), and power factor (PF) of polycrystalline Bi{sub 1-x}Sb{sub x} (x?=?0.10 and 0.14) samples are reported. Temperature-dependent powder diffraction experiments indicate that samples do not undergo any structural phase transition. Rietveld refinement technique has been used to perform detailed structural analysis. Temperature dependence of ? is found to be stronger for Bi{sub 0.90}Sb{sub 0.10}. Also, PF for direct band gap Bi{sub 0.90}Sb{sub 0.10} is higher as compared to that for indirect band gap Bi{sub 0.86}Sb{sub 0.14}. Role of electron-electron and electron-phonon scattering on ?, S, and PF has been discussed.

  11. Effect of Ti doping on high pressure behavior of BiMn{sub 2}O{sub 5}

    SciTech Connect (OSTI)

    Pandey, K. K., E-mail: kkpandey@barc.gov.in; Poswal, H. K., E-mail: kkpandey@barc.gov.in; Sharma, Surinder M. [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 40008 (India); Kumar, Ravi [Centre for Materials Science and Engineering, National Institute of Technology, Hamirpur-177005 (India)

    2014-04-24T23:59:59.000Z

    Our high pressure x-ray diffraction studies on BiMn{sub 1.5}Ti{sub 0.5}O{sub 5} show iso-structural phase transition above 12 GPa similar to the one observed in undoped BiMn{sub 2}O{sub 5}; however anisotropic compressional behavior is found to be more enhanced in the doped case. Unlike undoped system, an anomalous lattice expansion along c axis has been observed in BiMn{sub 1.5}Ti{sub 0.5}O{sub 5} above 12 GPa; whereas the b lattice parameter has been found to be more compressible as compared to BiMn{sub 2}O{sub 5}. As doping with Ti reduces the magnetic interactions among Mn ions, the observed changes are suggestive of having adverse magnetic implications in the observed iso-structural phase transition.

  12. Evidence of local superconductivity in granular Bi nanowires fabricated by electrodeposition Mingliang Tian, Nitesh Kumar, and Moses H. W. Chan

    E-Print Network [OSTI]

    by electrodepositing Bi into porous polycarbonate membranes, showed granular morphology consisting of crystalline nanowires. In the 20 nonsuper- conducting granular wires we investigated, nine of them showed an unusual

  13. Local structure underlying anomalous tetragonal distortions in BiFeO{sub 3}-PbTiO{sub 3} ferroelectrics

    SciTech Connect (OSTI)

    Levin, I.; Krayzman, V.; Woicik, J. C. [Materials Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Tucker, M. G. [ISIS Facility, Rutherford Appleton Laboratory, Didcot (United Kingdom)

    2014-06-16T23:59:59.000Z

    The local structure of tetragonal BiFeO{sub 3}-PbTiO{sub 3} solid solutions featuring anomalous lattice distortions has been determined using simultaneous fitting of neutron total scattering and extended X-ray absorption fine structure data. On the local scale, the large tetragonal distortion, promoted by the displacements of the A-cations (Bi and Pb), is accommodated primarily by the [FeO{sub 6}] octahedra, even though both Fe and Ti acquire (5+1)-fold coordination. Bi cations exhibit considerably larger displacements than Pb. The combination of the A-cation displacements and the ability of M-cations to adopt 5-fold coordination is suggested as key for stabilizing the large tetragonality in BiMO{sub 3}-PbTiO{sub 3} systems.

  14. BuildSense Compressed natural gas (CNG) bi-fuel conversions for two Ford F-series pickup trucks.

    E-Print Network [OSTI]

    BuildSense Compressed natural gas (CNG) bi-fuel conversions for two Ford F-series pickup trucks $141,279 $35,320 $176,599 City of Charlotte Solid Waste Services Compressed natural gas ( CNG) up fits

  15. Potential commercial application of a bi-layer bone-ligament regeneration scaffold to anterior cruciate ligament replacement

    E-Print Network [OSTI]

    Li, Jessica C. (Jessica Ching-Yi)

    2006-01-01T23:59:59.000Z

    A business model was created in order to explore the commercial application of a bi-layer bone-ligament scaffold to the treatment of torn anterior cruciate ligaments (ACL) requiring replacement. The two main keys in producing ...

  16. Variation in p-mode power over solar cycle 23 as seen from BiSON and GOLF observations

    E-Print Network [OSTI]

    R. Simoniello; D. Salabert; R. A. Garcia

    2008-10-10T23:59:59.000Z

    We analyzed BiSON and GOLF/SoHO data with a new technique, to investigate p-mode power variation over solar cycle 23. We found a decrease in the mean velocity power of about 20% for BiSON during the ascending phase, in agreement with previous findings. We also found that GOLF, during the red-wing configuration, seems to be working at a different height than the theoretically computed one.

  17. The bi-variate frequency distribution of two concurrent climatic variables: a study of temperature and dew point 

    E-Print Network [OSTI]

    Zeitler, Jon William

    1991-01-01T23:59:59.000Z

    Study of Temperature and Dew Point (December 1991). Jon William Zeitler, B. S. , iowa State University Chair of Advisory Comminee; Prof. John F. Griffiths The bi-variate normal distribution was fitted for the mid-season months of January, April, July... as to style and content by: Jo F. Griffnhs "' (Chair of Committee) Robert C. Runnels (Member) J. ' e (Mem r) Edward J. ser (Head of Department) December 1991 ABSTRACT The Bi-Variate Frequency Distribution of Two Concurrent Climatic Variables: A...

  18. Sanden Vendo America: Proposed Penalty (2014-SE-52002) | Department of

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

    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 on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin ofEnergy atLLC - FE DKT. 10-160-LNG -Energy Proposed Penalty (2014-SE-52002)

  19. Analysis of the bi-modal nature of solar wind-magnetosphere coupling

    SciTech Connect (OSTI)

    Smith, J.P.; Horton, W.

    1997-05-01T23:59:59.000Z

    It has been shown that the optimal linear prediction filter relating the solar wind electric field and the geomagnetic activity, as measured by the AL index, is both bi-modal and dependent on the level of activity in the magnetosphere. Further studies truncated the prediction filter to a five parameter model containing two low-pass filtered delta functions of arbitrary amplitude and delay time. The present study elaborates on the nature of the bi-modal response by using the five parameter model to quantify the effects of the level of geomagnetic activity on each of the modes of the filter individually. The authors find that at all levels of activity, the second mode, occurring at approximately one hour, is relatively unchanged. The first mode, however, has a one parameter dependence on the level of activity in the magnetosphere. The amplitude of the first mode is shown to have a significant increase with respect to activity.

  20. Couple Control Model Implementation on Antagonistic Mono- and Bi-Articular Actuators

    E-Print Network [OSTI]

    Prattico, Flavio; Yamamoto, Shin-ichiroh

    2014-01-01T23:59:59.000Z

    Recently, robot assisted therapy devices are increasingly used for spinal cord injury (SCI) rehabilitation in assisting handicapped patients to regain their impaired movements. Assistive robotic systems may not be able to cure or fully compensate impairments, but it should be able to assist certain impaired functions and ease movements. In this study, a couple control model for lower-limb orthosis of a body weight support gait training system is proposed. The developed leg orthosis implements the use of pneumatic artificial muscle as an actuation system. The pneumatic muscle was arranged antagonistically to form two pair of mono-articular muscles (i.e., hip and knee joints), and a pair of bi-articular actuators (i.e., rectus femoris and hamstring). The results of the proposed couple control model showed that, it was able to simultaneously control the antagonistic mono- and bi-articular actuators and sufficiently performed walking motion of the leg orthosis.

  1. Neutron density distributions from antiprotonic 208Pb and 209Bi atoms

    E-Print Network [OSTI]

    Klos, B; Czosnyka, T; Gulda, K; Hartmann, F J; Jastrzebski, J J; Ketzer, B; Kisielinski, M; Kurcewicz, W; Lubinski, P; Napiorkowski, P J; Pienkowski, L; Ring, P; Schmidt, R; Smolanczuk, R; Trzcinska, A; Von Egidy, T; Widmann, E; Wycech, S

    2007-01-01T23:59:59.000Z

    The X-ray cascade from antiprotonic atoms was studied for 208Pb and 209Bi. Widths and shifts of the levels due to the strong interaction were determined. Using modern antiproton-nucleus optical potentials the neutron densities in the nuclear periphery were deduced. Assuming two parameter Fermi distributions (2pF) describing the proton and neutron densities the neutron rms radii were deduced for both nuclei. The difference of neutron and proton rms radii /\\r_np equal to 0.16 +-(0.02)_{stat} +- (0.04)_{syst} fm for 208Pb and 0.14 +- (0.04)_{stat} +- (0.04)_{syst} fm for 209Bi were determined and the assigned systematic errors are discussed. The /\\r_np values and the deduced shapes of the neutron distributions are compared with mean field model calculations.

  2. MnBi particles with high energy density made by spark erosion

    SciTech Connect (OSTI)

    Nguyen, Phi-Khanh, E-mail: phi@ucsd.edu; Jin, Sungho [Materials Science and Engineering, University of California, San Diego, La Jolla, California 92093 (United States); Center for Magnetic Recording Research, University of California, San Diego, La Jolla, California 92093 (United States); Berkowitz, Ami E. [Physics Department, University of California, San Diego, La Jolla, California 92093 (United States); Center for Magnetic Recording Research, University of California, San Diego, La Jolla, California 92093 (United States)

    2014-05-07T23:59:59.000Z

    We report on the properties of low-temperature phase (LTP)-MnBi particles produced by the rapid-quenching technique of spark-erosion. The as-prepared powder consists of amorphous, crystalline, and superparamagnetic particles, mostly as porous aggregates. The major fraction of the powder consists of 20–30?nm particles. A short anneal crystallizes the amorphous particles producing a high moment, >90% of theoretical M{sub S}, albeit with H{sub C} of a few kOe. If lightly milled, the agglomerates are broken up to yield H{sub C} of 1?T. These findings are supported by the x-ray diffraction pattern showing broadened peaks of the predominant LTP-MnBi phase. The combination of spark erosion, milling, and annealing has produced randomly oriented particles with (BH){sub MAX}???3.0 MGOe. The particles are expected to show record energy product when aligned along their crystallographic easy axes.

  3. A Comprehensive Approach to Bi-National Regional Energy Planning in the Pacific Northwest

    SciTech Connect (OSTI)

    Matt Morrison

    2007-12-31T23:59:59.000Z

    The Pacific NorthWest Economic Region, a statutory organization chartered by the Northwest states of Alaska, Washington, Idaho, Montana, and Oregon, and the western Canadian provinces of British Columbia, Alberta, and the Yukon through its Energy Working Group launched a bi-national energy planning initiative designed to create a Pacific Northwest energy planning council of regional public/private stakeholders from both Canada and the US. There is an urgent need to deal with the comprehensive energy picture now before our hoped for economic recovery results in energy price spikes which are likely to happen because the current supply will not meet predicted demand. Also recent events of August 14th have shown that our bi-national energy grid system is intricately interdependent, and additional planning for future capacity is desperately needed.

  4. Preparation and Magnetic Properties of MnBi-based Hard/Soft Composite Magnets

    SciTech Connect (OSTI)

    Ma, Yilong; Liu, Xubo; Gandha, Kinjal; Vuong, Nguyen V.; Yang, Y. B.; Yang, Jinbo; Poudyal, Narayan; Cui, Jun; Liu, J.Ping

    2014-05-07T23:59:59.000Z

    Bulk anisotropic composite magnets based on MnBi/Co(Fe) exhibiting the different morphology of the soft magnetic phase were prepared by powder metallurgy processing. First, single-phase MnBi bulk magnets were produced using a maximum energy product [(BH)m] of 6.3 MGOe at room temperature. The nanoscale soft phase with the different morphology was then added to form a composite magnet. It was observed that addition of magnetic soft-phase nanoparticles and nanoflakes causes a dramatic coercivity reduction. However, the addition of soft magnetic phase nanowires enhanced the composite magnetization without sacrificing the coercivity. Nevertheless, a kink was still observed on the demagnetization curves and the coercivity decreased when the soft-phase content was larger than 10 wt. %, which was caused by the agglomeration of the soft phase nanowires that also led to a decreased degree of texture.

  5. Fragile antiferromagnetism in the heavy-fermion compound YbBiPt

    SciTech Connect (OSTI)

    Ueland, Benjamin G. [Ames Laboratory; Kreyssig, Andreas [Ames Laboratory; Prokes, K. [Helmholtz-Zentrum Berlin fur Materialien und Energie; Lynn, J. W. [NIST Center for Neutron Research; Harriger, L. W. [NIST Center for Neutron Research; Pratt, D. K. [NIST Center for Neutron Research; Singh, D. K. [NIST Center for Neutron Research; Heitmann, T. W. [University of Missouri; Sauerbrei, Samantha [Ames Laboratory; Saunders, Scott M. [Ames Laboratory; Mun, E. D. [Ames Laboratory; Budko, Serguei L. [Ames Laboratory; McQueeney, Robert J. [Ames Laboratory; Canfield, Paul C. [Ames Laboratory; Goldman, Alan I. [Ames Laboratory

    2014-05-08T23:59:59.000Z

    We report results from neutron scattering experiments on single crystals of YbBiPt that demonstrate antiferromagnetic order characterized by a propagation vector, ?AFM = (121212), and ordered moments that align along the [1 1 1] direction of the cubic unit cell. We describe the scattering in terms of a two-Gaussian peak fit, which consists of a narrower component that appears below TN?0.4 K and corresponds to a magnetic correlation length of ?n? 80 Ĺ, and a broad component that persists up to T?? 0.7 K and corresponds to antiferromagnetic correlations extending over ?b? 20 Ĺ. Our results illustrate the fragile magnetic order present in YbBiPt and provide a path forward for microscopic investigations of the ground states and fluctuations associated with the purported quantum critical point in this heavy-fermion compound.

  6. Bi-antimony capped Keggin polyoxometalate modified with Cu-ligand fragment

    SciTech Connect (OSTI)

    Huang, Jiao [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China)] [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China); Han, Zhangang, E-mail: hanzg116@yahoo.com.cn [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China)] [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China); Zhang, Heng; Yu, Haitao [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China)] [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China); Zhai, Xueliang, E-mail: xlzhai253@mail.hebtu.edu.cn [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China)] [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China)

    2012-10-15T23:59:59.000Z

    Three polyoxometalates consisting of bi-antimony capped Keggin-type clusters: [Cu(mbpy){sub 2}]{sub 2}[PMo{sub 12}O{sub 40}Sb{sub 2}]{center_dot}4H{sub 2}O (1), [Cu(mbpy){sub 2}][PMo{sub 12}O{sub 40}Sb{sub 2}] (2) and {l_brace}Cu(mbpy)[Cu(mbpy){sub 2}]{sub 2}{r_brace}[VMo{sub 8}V{sub 4}O{sub 40}Sb{sub 2}]{center_dot}2H{sub 2}O (3) (mbpy=4,4 Prime -dimethyl-2,2 Prime - dipyridyl in 1 and 2; 5,5 Prime -dimethyl-2,2 Prime -dipyridyl in 3) have been synthesized and characterized by IR, X-ray powder diffraction, TG analysis and electrochemical property. Single-crystal analysis revealed that all of three compounds are built upon bi-antimony capped Keggin-type polyoxoanions and Cu-mbpy cations. In 1-3, two Sb{sup III} centers located at the two opposite of anionic surface adopt fundamentally tetragonal pyramidal coordination geometry. Both compounds 1 and 2 consist of P-centered Keggin structure, while compound 3 presents a V-centered Keggin anion. The Keggin-type anions present different structural features: isolated cluster in 1 and Cu-ligand-supported cluster in 2 and 3. - Graphical abstract: Three hybrid compounds consisting of bi-antimony capped Keggin-type clusters modified with Cu-ligand cations have been synthesized and characterized. Highlights: Black-Right-Pointing-Pointer Three hybrid compounds consisting of bi-antimony capped Keggin-type clusters have been synthesized. Black-Right-Pointing-Pointer Two Sb{sup III} centers located at the two opposite of anionic surface adopt tetragonal pyramidal coordination geometry. Black-Right-Pointing-Pointer The anions present different structural features: isolated and Cu-ligand-supported cluster.

  7. Quasi-linear heating and acceleration in bi-Maxwellian plasmas

    SciTech Connect (OSTI)

    Hellinger, Petr [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic)] [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic); Passot, Thierry; Sulem, Pierre-Louis [Université de Nice Sophia Antipolis, CNRS, Observatoire de la Côte d'Azur, BP 4229, 06304 Nice Cedex 4 (France)] [Université de Nice Sophia Antipolis, CNRS, Observatoire de la Côte d'Azur, BP 4229, 06304 Nice Cedex 4 (France); Trávní?ek, Pavel M. [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic) [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic); Space Sciences Laboratory, University of Berkeley, 7 Gauss Way, Berkeley, California 94720 (United States)

    2013-12-15T23:59:59.000Z

    Quasi-linear acceleration and heating rates are derived for drifting bi-Maxwellian distribution functions in a general nonrelativistic case for arbitrary wave vectors, propagation angles, and growth/damping rates. The heating rates in a proton-electron plasma due to ion-cyclotron/kinetic Alfvén and mirror waves for a wide range of wavelengths, directions of propagation, and growth or damping rates are explicitly computed.

  8. Bi-Continuous Domains and Some Old Problems in Domain Theory

    E-Print Network [OSTI]

    Keimel, Klaus

    . One says that P is a continuous poset if, for every b P the set b = {a P | a b} is directed and b poset if, for every a P the set da = {b P | a d b} is filtered and a = da. The Scott topology on a bi-continuous poset has as a basis for the opens the set of the form a, the dual Scott topology the sets of the form

  9. Microstructure and properties of Bi-Sr-Ca-Cu-O with nanometer-scale alumina additions.

    SciTech Connect (OSTI)

    Goretta, K. C.

    1998-09-11T23:59:59.000Z

    Al{sub 2}O{sub 3} particles {approx}30 nm is size were added to Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} in a 1:4 molar ratio. For comparison, 0.3 and {approx}3 pm Al{sub 2}O{sub 3} particles were added to separate batches. All materials were partial-melt processed. The Al{sub 2}O{sub 3} reacted during melting to primarily form stable compounds of approximate composition (Sr,Ca){sub 2}AlO{sub 4}. All additions caused slight decreases in the T{sub c} and melting point of the Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x}. The submicrometer Al{sub 2}O{sub 3} additions induced large expansions in magnetic-hysteresis width at 6 K. Electron microscopy examinations strongly suggested that the hysteresis expansion was related to alloying of the Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} matrix rather than to pinning by volume defects.

  10. Tunable atomic termination in nano-necklace BiFeO{sub 3}

    SciTech Connect (OSTI)

    Sobhan, Mushtaq; Xu, Qiang; Yang, Qian; Anariba, Franklin; Wu, Ping, E-mail: wuping@sutd.edu.sg [Entropic Interface Group (EIG), Engineering Product Development, Singapore University of Technology and Design (SUTD), 20 Dover Drive (Singapore)

    2014-02-03T23:59:59.000Z

    We investigate the growth kinetics of BiFeO{sub 3} (BFO) nano-necklace based on first principles modeling and electrospinning experiments. A two-step layered growth mechanism is proposed to control the atomic termination of each nano-necklace. X-ray diffraction (XRD) results agree well with our model predictions; (1) samples calcined at 500 and 550?°C consist of FeO{sub 2} (F-F) terminated nano-necklace, (2) samples calcined at 650?°C consist of either BiO (B-B) or BiO and FeO{sub 2} (B-F) terminated ones. The XRD diffraction peaks are located at lower 2? values with a magnetic moment of 3.0?emu/g for the former and at higher 2? values with a decrease in the magnetic moment to 0.4?emu/g for the later samples. The activation energy associated with the growth of the nano-necklaces was experimentally determined to be 0.37?eV/atom. This study provides fundamental understanding for the long-sought layer-by-layer assembly of BFO nanostructures.

  11. Interplay between intrinsic and stacking-fault magnetic domains in bi-layered manganites

    SciTech Connect (OSTI)

    Hossain, M.A; Burkhardt, Mark H.; Sarkar, S.; Ohldag, H.; Chuang, Y.-D.; Scholl, A.; Young, A.T.; Doran, A.; Dessau, D.S.; Zheng, H.; Mitchell, J.F.; Durr, H.A.; Stohr, J.

    2012-09-11T23:59:59.000Z

    We present a low temperature X-ray photoemission electron microscopy study of the bi-layered manganite compound La{sub 1.2}Sr{sub 1.8}Mn{sub 2}O{sub 7} (BL-LSMO) to investigate the influence of stacking faults, which are structurally and magnetically different from the bi-layered host. In BL-LSMO small magnetic moment persists to T* = 300K, well above the Curie temperature of 120K (T{sub C}). Our magnetic images show that 3D stacking faults are responsible for the T* transition. Furthermore, close to the T{sub C}, stacking faults are well coupled to the bi-layered host with latter magnetic domains controlling the spin direction of the stacking faults. Contrary to recent reports, we find that stacking faults do not seed magnetic domains in the host via an exchange spring mechanism and the intrinsic T{sub C} of the BL-LSMO is not lower than 120K.

  12. BiPo: A dedicated radiopurity detector for the SuperNEMO experiment

    SciTech Connect (OSTI)

    Gómez, H. [Laboratoire de l'Accélérateur Linéaire. Centre Scientifique d'Orsay. Bâtiment 200 - BP 34. 91898 ORSAY Cedex (France)] [Laboratoire de l'Accélérateur Linéaire. Centre Scientifique d'Orsay. Bâtiment 200 - BP 34. 91898 ORSAY Cedex (France); Collaboration: SuperNEMO Collaboration; and others

    2013-08-08T23:59:59.000Z

    New generation experiments in Astroparticle Physics need to operate in really restrictive background conditions, which implies the use of high radiopure materials for the experimental setup construction. For this reason the screening of the materials with enough sensitivity has become a challenge that sometimes cannot be afforded with standard techniques like Germanium detector spectroscopy. BiPo is a dedicated detector, that operates in the Canfranc Underground Laboratory, designed to measure the radiopurity, mainly of the ?? sources of the SuperNEMO experiment, by the detection of BiPo events. It is composed of two modules with 40 optical lines each one, registering the energy and the time of the emitted particles. The well known features of the BiPo events (delayed coincidence between an electron and an alpha particle) facilitate the discrimination of other background events that could entangle the expected signal. In addition, the geometry of the detector, with an active area of around 3.6 m{sup 2}, has been optimized to reach the necessary sensitivity levels for the SuperNEMO source foils in the shortest time possible. Preliminary results of background measurements and calibrations taken since summer 2012 shows that the required sensitivity for the measurements of the source foils could be reached in few months. Routine measurements of samples are already started being an important point for the SuperNEMO source foils construction.

  13. 110K Bi-Sr-Ca-Cu-O superconductor oxide and method for making same

    DOE Patents [OSTI]

    Veal, B.W.; Downey, J.W.; Lam, D.J.; Paulikas, A.P.

    1992-12-22T23:59:59.000Z

    A superconductor is disclosed consisting of a sufficiently pure phase of the oxides of Bi, Sr, Ca, and Cu to exhibit a resistive zero near 110K resulting from the process of forming a mixture of Bi[sub 2]O[sub 3], SrCO[sub 3], CaCO[sub 3] and CuO into a particulate compact wherein the atom ratios are Bi[sub 2], Sr[sub 1.2-2.2], Ca[sub 1.8-2.4], Cu[sub 3]. Thereafter, heating the particulate compact rapidly in the presence of oxygen to an elevated temperature near the melting point of the oxides to form a sintered compact, and then maintaining the sintered compact at the elevated temperature for a prolonged period of time. The sintered compact is cooled and reground. Thereafter, the reground particulate material is compacted and heated in the presence of oxygen to an elevated temperature near the melting point of the oxide and maintained at the elevated temperature for a time sufficient to provide a sufficiently pure phase to exhibit a resistive zero near 110K. 7 figs.

  14. Enhanced magnetization and improved insulating character in Eu substituted BiFeO{sub 3}

    SciTech Connect (OSTI)

    Durga Rao, T.; Asthana, Saket, E-mail: asthanas@iith.ac.in [Advanced Functional Materials Laboratory, Department of Physics, Indian Institute of Technology Hyderabad, Andhra Pradesh–502205 (India); Ranjith, R. [Department of Materials Science and Metallurgical Engineering, Indian Institute of Technology Hyderabad, Andhra Pradesh–502205 (India)

    2014-03-28T23:59:59.000Z

    The polycrystalline Bi{sub 1?x}Eu{sub x}FeO{sub 3} (x?=?0, 0.05, and 0.1) ceramics were synthesized by conventional solid-state route. X-ray diffraction studies and Raman measurements revealed that the compounds crystallized in rhombohedral structure with R3c space group. In addition, a nominal percentage of orthorhombic phase was observed in 10 mol.?% Eu substituted BiFeO{sub 3}. Appearance of weak ferromagnetism and significant increase in Néel temperature T{sub N} in the substituted compounds were discussed on the basis of structural distortions. Enhanced remnant magnetization of 75 memu/g and large coercive field of 6.4?kÖe were observed in 10 mol.?% Eu substituted BiFeO{sub 3}. Equivalent circuit model was employed to estimate the grain and grain boundary contributions towards the electrical parameters such as resistance and conductivity. Non-Debye type of relaxation was confirmed from impedance and electric modulus studies. The obtained frequency variation of ac conductivity at different temperature obeys Jonscher's power law and is consistent with the correlated barrier hopping model. Temperature variations of ac conductivity explained that electronic hopping, oxygen vacancies movement, and/or creation of defects contribute to conduction in all the compounds.

  15. Structure, nonlinear properties, and photosensitivity of (GeSe2)100-x(Sb2Se3)x glasses

    E-Print Network [OSTI]

    -Anne, J. Charrier, J.-P. Guin, and A. Moréac, "Sputtering and pulsed laser deposition for near- and mid-infrared to increase the n2 from 2 to 710-18 m2 /W for As2S3 glass to 11-3010-18 m2 /W for As2Se3 glass at near-infrared measurements were performed with 10 mg powdered samples, heated up to 450°C at heating rate of 10 °C.min-1

  16. Fabrication and testing of diamond-machined gratings in ZnSe, GaP, and bismuth germanate for the near infrared and visible

    SciTech Connect (OSTI)

    Kuzmenko, P J; Little, S L; Ikeda, Y; Kobayashi, N

    2008-06-22T23:59:59.000Z

    High quality immersion gratings for infrared applications have been demonstrated in silicon and germanium. To extend this technology to shorter wavelengths other materials must be investigated. We selected three materials, zinc selenide, gallium phosphide and bismuth germanate (Bi{sub 4}Ge{sub 3}O{sub 12}), based on high refractive index, good visible transmission and commercial availability in useful sizes. Crystal samples were diamond turned on an ultra-precision lathe to identify preferred cutting directions. Using this information we diamond-flycut test gratings over a range of feed rates to determine the optimal cutting conditions. For both ZnSe and GaP good surface quality was achieved at feed rates up to 1.0 cm/minute using a special compound angle diamond tool with negative rake angles on both cutting surfaces. The surface roughness of the groove facets was about 4 nm. A Zygo interferometer measured grating wavefront errors in reflection. For the ZnSe the RMS error was < {lambda}/20 at 633nm. More extensive testing was performed with a HeNe laser source and a cooled CCD camera. These measurements demonstrated high relative diffraction efficiency (> 80%), low random groove error (2.0 nm rms), and Rowland ghost intensities at < 0.1%. Preliminary tests on bismuth germanate show high tool wear.

  17. Cobalt-doped Bi{sub 26}Mo{sub 10}O{sub 69}: Crystal structure and conductivity

    SciTech Connect (OSTI)

    Mikhailovskaya, Z.A., E-mail: zozoikina@mail.ru [Ural Federal University, Lenin Ave. 51, 620000 Ekaterinburg (Russian Federation); Buyanova, E.S. [Ural Federal University, Lenin Ave. 51, 620000 Ekaterinburg (Russian Federation); Petrova, S.A. [Institute of Metallurgy, Ural Branch of the Russian Academy of Sciences, 101 Amundsen Str., 620016 Ekaterinburg (Russian Federation); Morozova, M.V.; Zhukovskiy, V.M. [Ural Federal University, Lenin Ave. 51, 620000 Ekaterinburg (Russian Federation); Zakharov, R.G. [Institute of Metallurgy, Ural Branch of the Russian Academy of Sciences, 101 Amundsen Str., 620016 Ekaterinburg (Russian Federation); Tarakina, N.V. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 91 Pervomayskaya Str., 620990 Ekaterinburg (Russian Federation); Experimentelle Physik III, Physikalisches Institut and Wilhelm Conrad Röntgen—Research Centre for Complex Material Systems, Universität Würzburg, Am Hubland, D-97074 Würzburg (Germany); Berger, I.F. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 91 Pervomayskaya Str., 620990 Ekaterinburg (Russian Federation)

    2013-08-15T23:59:59.000Z

    A series of cobalt-doped bismuth molybdates were synthesized and investigated using X-ray powder diffraction, transmission electron microscopy and impedance spectroscopy. The ranges of solid solution were determined. Two new compounds, Bi{sub 1?x}Co{sub x}[Bi{sub 12}O{sub 14}]Mo{sub 5}O{sub 34.5±?} (x=0.2) and Bi[Bi{sub 12}O{sub 14}]Mo{sub 5?y}Co{sub y}O{sub 34.5±?} (y=0.2), which crystallise in monoclinic unit cells have been examined in detail by diffraction methods. Impedance spectroscopy measurements show that the studied materials are good ionic conductors with conductivity values about 5×10{sup ?3} S×cm{sup ?1} at 973 K and 1.7×10{sup ?4} S×cm{sup ?1} at 623 K, which are similar to conductivity values of yttrium substituted zirconia and (YSZ) gadolinium doped ceria (CGO). - Graphical abstract: Measured and calculated diffraction spectra for Bi{sub 12.8}Co{sub 0.2}Mo{sub 5}O{sub 34±?} and projection of the Bi{sub 12.8}Co{sub 0.2}Mo{sub 5}O{sub 34±?} crystal structure onto the ac plane. Highlights: • The limit of the Bi{sub 1?x}Co{sub x}[Bi{sub 12}O{sub 14}]Mo{sub 5}O{sub 34.5±?} homogeneity range is equal to x=0.2. • The limit of the Bi[Bi{sub 12}O{sub 14}]Mo{sub 5?y}Co{sub y}O{sub 34.5±?} homogeneity range is equal to y=0.2. • Solid solutions have monoclinic symmetry. No phase transition is observed. • The conductivity at 700° for y=0.2 solid solutions is equal to ?lg ?, S×cm{sup ?1}=2.23. • The conductivity at 350° for y=0.2 solid solutions is equal to ?lg ?, S×cm{sup ?1}=3.74.

  18. Fluorescence quenching of CdSe quantum dots on graphene

    SciTech Connect (OSTI)

    Guo, Xi Tao; Hua Ni, Zhen, E-mail: zhni@seu.edu.cn; Yan Nan, Hai; Hui Wang, Wen [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China)] [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China); Yan Liao, Chun [Physics Department, National Photoelectric Technology and Functional Materials and Application of Science and Technology International Cooperation Base, Northwest University, Xi'an 710069 (China)] [Physics Department, National Photoelectric Technology and Functional Materials and Application of Science and Technology International Cooperation Base, Northwest University, Xi'an 710069 (China); Zhang, Yan; Wei Zhao, Wei [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)] [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)

    2013-11-11T23:59:59.000Z

    We studied systematically the fluorescence quenching of CdSe quantum dots (QDs) on graphene and its multilayers, as well as graphene oxide (GO) and reduced graphene oxide (rGO). Raman intensity of QDs was used as a quantitatively measurement of its concentration in order to achieve a reliable quenching factor (QF). It was found that the QF of graphene (?13.1) and its multilayers is much larger than rGO (?4.4), while GO (?1.5) has the lowest quenching efficiency, which suggests that the graphitic structure is an important factor for quenching the fluorescence of QDs. It was also revealed that the QF of graphene is not strongly dependent on its thicknesses.

  19. Effect of selenium deficiency on the thermoelectric properties of n-type In4Se3-x [In subscript 4 Se subscript 3-x] compounds

    E-Print Network [OSTI]

    Zhu, G. H.

    Thermoelectric properties of dense bulk polycrystalline In4Se3?x [In subscript 4 Se subscript 3-x] (x = 0, 0.25, 0.5, 0.65, and 0.8) compounds

  20. Proposal for the award of blanket purchase contracts for the supply and maintenance of light petrol and light bi-fuel vehicles

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    Proposal for the award of blanket purchase contracts for the supply and maintenance of light petrol and light bi-fuel vehicles

  1. MoSe2 thin films synthesized by solid state reactions between Mo and Se J. Pouzet (1) and J. C. Bernede (2)

    E-Print Network [OSTI]

    Boyer, Edmond

    807 MoSe2 thin films synthesized by solid state reactions between Mo and Se thin films J. Pouzet (1 reaction, induced by annealing, between the Mo and Se constituents in thin films form. The films have been thin films annealed under selenium pressure at only 770 K are well crystallized. The electrical

  2. Photoluminescence study of the substitution of Cd by Zn during the growth by atomic layer epitaxy of alternate CdSe and ZnSe monolayers

    SciTech Connect (OSTI)

    Hernández-Calderón, I. [Physics Department,Cinvestav, Ave. IPN2508, 07360, México City, DF. (Mexico); Salcedo-Reyes, J. C. [Thin Films Group, Physics Department, Pontificia Universidad Javeriana, Cr. 7 No. 43-82, Ed. 53, Lab. 404, Bogotá, D.C. (Colombia)

    2014-05-15T23:59:59.000Z

    We present a study of the substitution of Cd atoms by Zn atoms during the growth of alternate ZnSe and CdSe compound monolayers (ML) by atomic layer epitaxy (ALE) as a function of substrate temperature. Samples contained two quantum wells (QWs), each one made of alternate CdSe and ZnSe monolayers with total thickness of 12 ML but different growth parameters. The QWs were studied by low temperature photoluminescence (PL) spectroscopy. We show that the Cd content of underlying CdSe layers is affected by the exposure of the quantum well film to the Zn flux during the growth of ZnSe monolayers. The amount of Cd of the quantum well film decreases with higher exposures to the Zn flux. A brief discussion about the difficulties to grow the Zn{sub 0.5}Cd{sub 0.5}Se ordered alloy (CuAu-I type) by ALE is presented.

  3. The influence of Se pressure on the electronic properties of CuInSe{sub 2} grown under Cu-excess

    SciTech Connect (OSTI)

    Deprédurand, Valérie; Bertram, Tobias; Regesch, David; Henx, Benjamin; Siebentritt, Susanne [Laboratory for Photovoltaics, Physics and Materials Science Research Unit, University of Luxembourg, L-4422 Belvaux (Luxembourg)

    2014-10-27T23:59:59.000Z

    Standard Cu-poor Cu(In,Ga)Se{sub 2} solar cell absorbers are usually prepared under high Se excess since the electronic properties of the absorbers are better if prepared under high Se pressure. However, in CuInSe{sub 2}, grown under Cu-excess, it was found that solar cell properties improve with lowering the Se pressure, mostly because of reduced tunnel contribution to the recombination path. Lower Se pressure during Cu-rich growth leads to increased (112) texture of the absorber films, to better optical film quality, as seen by increased excitonic luminescence and to lower net doping levels, which explains the reduced tunnelling effect. These findings show an opposite trend from the one observed in Cu-poor Cu(In,Ga)Se{sub 2}.

  4. Microwave synthesis and electrochemical characterization of mesoporous carbon@Bi{sub 2}O{sub 3} composites

    SciTech Connect (OSTI)

    Xia, Nannan [Department of Chemistry and Institute of Nanochemistry, Jinan University, Guangzhou 510632 (China)] [Department of Chemistry and Institute of Nanochemistry, Jinan University, Guangzhou 510632 (China); Yuan, Dingsheng, E-mail: tydsh@jnu.edu.cn [Department of Chemistry and Institute of Nanochemistry, Jinan University, Guangzhou 510632 (China)] [Department of Chemistry and Institute of Nanochemistry, Jinan University, Guangzhou 510632 (China); Zhou, Tianxiang; Chen, Jingxing; Mo, Shanshan; Liu, Yingliang [Department of Chemistry and Institute of Nanochemistry, Jinan University, Guangzhou 510632 (China)] [Department of Chemistry and Institute of Nanochemistry, Jinan University, Guangzhou 510632 (China)

    2011-05-15T23:59:59.000Z

    Graphical abstract: An efficient and quick microwave method has been employed to prepare worm-like mesoporous carbon@Bi{sub 2}O{sub 3} composites for the first time. The electrochemical measurement shows the worm-like mesoporous carbon@Bi{sub 2}O{sub 3} composites exhibits excellent capacitance performance and the maximum specific capacitance is up to 386 F g{sup -1}. Research highlights: {yields} An efficient and quick microwave method has been employed. {yields} A worm-like mesoporous carbon@Bi{sub 2}O{sub 3} composites have been successfully prepared. {yields} This composite exhibits excellent capacitance performance. {yields} This composite could be a potential electrode material for the supercapacitors. -- Abstract: An efficient and quick microwave method has been employed to prepare worm-like mesoporous carbon@Bi{sub 2}O{sub 3} composites for the first time. As-prepared products have been characterized by X-ray diffraction, N{sub 2} adsorption-desorption, scanning electron microscopy, transmission electron microscopy and inductive coupled plasma atomic emission spectroscopy. The electrochemical measurement shows the worm-like mesoporous carbon@Bi{sub 2}O{sub 3} composites exhibits excellent capacitance performance and the maximum specific capacitance reaches 386 F g{sup -1}, three times more than the pure worm-like mesoporous carbon.

  5. Enhanced open voltage of BiFeO{sub 3} polycrystalline film by surface modification of organolead halide perovskite

    SciTech Connect (OSTI)

    Zhao, Pengjun [Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Bian, Liang; Xu, Jinbao, E-mail: xujb@ms.xjb.ac.cn; Chang, Aimin [Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011 (China); Wang, Lei [Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011 (China); Department of Research and Development, Shanghai Shanshan Tech. Co., Ltd., Shanghai 201209, China and Department of Chemistry, Zhejiang University, Hangzhou 310027 (China)

    2014-07-07T23:59:59.000Z

    Inorganic-organolead halide perovskite CH{sub 3}NH{sub 3}PbI{sub 3} modified BiFeO{sub 3} polycrystalline film has been established. The composite photoelectrode presents much larger open voltage and several magnitudes superior photoelectric conversion performance in comparison to the ordinary BiFeO{sub 3} polycrystalline film. The I-V curve shows that the short-circuit current (J{sub sc}) is 1.74?mA·cm{sup ?2} and open-circuit voltage (V{sub oc}) is 1.62?V, the device's photon to current efficiency is over 1%. The large open voltage and high photovoltaic efficiency is believed to attributed to the spontaneous polarization of composite perovskite induced by BiFeO{sub 3} lattice and modified reduced work function of the modified BiFeO{sub 3} surface. Our results clearly show that the present BiFeO{sub 3}-CH{sub 3}NH{sub 3}PbI{sub 3} planar device is capable to generate a large voltage in macro scale under visible light, leading an approach to further applications on photodetectors and optoelectronic switch.

  6. High thermoelectric performance BiSbTe alloy with unique low-dimensional structure

    SciTech Connect (OSTI)

    Xie Wenjie [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634-0978 (United States); Tang Xinfeng; Yan Yonggao; Zhang Qingjie [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Tritt, Terry M. [Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634-0978 (United States)

    2009-06-01T23:59:59.000Z

    We report a detailed description of an innovative route of a melt spinning (MS) technique combined with a subsequent spark plasma sintering process in order to obtain high performance p-type Bi{sub 0.52}Sb{sub 1.48}Te{sub 3} bulk material, which possesses a unique low-dimensional structure. The unique structure consists of an amorphous structure, 5-15 nm fine nanocrystalline regions, and coherent interfaces between the resulting nanocrystalline regions. Measurements of the thermopower, electrical conductivity, and thermal conductivity have been performed over a range of temperature of 300-400 K. We found that MS technique can give us considerable control over the resulting nanostructure with good thermal stability during the temperature range of 300-400 K and this unique structure can effectively adjust the transport of phonons and electrons, in a manner such that it is beneficial to the overall thermoelectric performance of the material, primarily a reduction in the lattice thermal conductivity. Subsequently, this results in a maximum figure of merit ZT value of 1.56 at 300 K for p-type Bi{sub 0.52}Sb{sub 1.48}Te{sub 3} bulk material. This ZT value is over a 50% improvement of that of the state of the art commercial Bi{sub 2}Te{sub 3} materials. We also report results of thermal cycling of this material for over one hundred cycles between 300-400 K. Our work offers an innovative route for developing high performance bismuth telluride based alloys and devices, which have even broader prospects for commercial applications. This technique may also be applicable to other thermoelectric materials.

  7. LISTE ELECTORALE BELFORT Bureau Secrtariat SeT NOM PRENOM DEPARTEMENT ETABLISSEMENT

    E-Print Network [OSTI]

    Jeanjean, Louis

    Serge FEMTO-ST ENERGIE UFC AHMED Fayez-Shakil SeT UTBM AIT ALI Kahina SeT UTBM AIT-CHEIK-BIHI Wafaa SeT UTBM AMRANE Sofiane FEMTO-ST ENERGIE UFC ASENSIO SAUTO Joseba FEMTO-ST ENERGIE UFC ATTIA Dhouha SeT UTBM BAERT Jérôme FEMTO-ST ENERGIE UFC BAKKALI Zouheir FEMTO-ST ENERGIE UTBM BASSO Gillian SeT UTBM

  8. Surface state dominated transport in topological insulator Bi{sub 2}Te{sub 3} nanowires

    SciTech Connect (OSTI)

    Hamdou, Bacel, E-mail: bhamdou@physnet.uni-hamburg.de; Gooth, Johannes; Dorn, August; Nielsch, Kornelius, E-mail: knielsch@physnet.uni-hamburg.de [Institute of Applied Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg (Germany)] [Institute of Applied Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg (Germany); Pippel, Eckhard [Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle (Germany)] [Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle (Germany)

    2013-11-04T23:59:59.000Z

    We report on low temperature magnetoresistance measurements on single-crystalline Bi{sub 2}Te{sub 3} nanowires synthesized via catalytic growth and post-annealing in a Te-rich atmosphere. The observation of Aharonov-Bohm oscillations indicates the presence of topological surface states. Analyses of Subnikov-de Haas oscillations in perpendicular magnetoresistance yield extremely low two-dimensional carrier concentrations and effective electron masses, and very high carrier mobilities. All our findings are in excellent agreement with theoretical predictions of massless Dirac fermions at the surfaces of topological insulators.

  9. The application of bi-level non-linear programming to the aluminum industry

    SciTech Connect (OSTI)

    Nicholls, M.

    1994-12-31T23:59:59.000Z

    In this paper a bi-level non-linear mathematical model of an aluminum smelter is described. The model is based on the Portland Aluminum smelter and aims at maximizing the aluminum production while minimizing the costs associated with the production of this maximum output. The model has two variables, the power input (kilo-Amperes) and the setting cycle (of the anode replacement). The solution algorithm, based on a grid search which enumerates the appropriate intersections of the resource and other constraints is then discussed. Additionally, some of the areas currently being developed, including sensitivity analysis and the incorporation of dependencies between some of the variables and coefficients are considered.

  10. Droplet destabilization during Bi catalyzed vapor-liquuid-solid growth of GaAs

    SciTech Connect (OSTI)

    DeJarld, M., E-mail: mdejarld@umich.edu; Nothern, D.; Millunchick, J. M. [Department of Materials Science and Engineering, University of Michigan 2300 Hayward Street, Ann Arbor, Michigan 48105 (United States)

    2014-03-21T23:59:59.000Z

    GaAs nanodiscs are grown in a molecular beam epitaxy chamber via the vapor-liquid-solid mechanism with liquid Bi as the catalyst. Each nanostructure consists of a series of increasingly larger overlapping discs. The structure forms during deposition due to the fact that the catalyst grows until reaching a critical size whereupon it destabilizes, dropping off the disc onto the substrate, where it catalyzes the growth of a new disc of larger radius. It is shown that critical size is limited by the sidewall wetting with a contact angle significantly smaller than the Gibb's criterion.

  11. A BiCMOS synchronous pulse discriminator for the LHCb calorimeter system

    E-Print Network [OSTI]

    Bota, S; Gascón, D; Graciani, R

    2002-01-01T23:59:59.000Z

    A monolithic prototype for the analogue readout of the Scintillator Pad Detector (SPD) of the LHCb calorimeter is presented. A low power version that works at 3.3 V has been designed using the 0.8 mu m Bi CMOS technology of AMS. It consists of a charge discriminator with a dual path structure formed by an integrator, a pile-up correction, a subtractor and a comparator. The chip also includes a DAC and serial digital control interface to program the threshold of the discriminator. Design, simulation and test results for different prototypes of the circuit will be presented and described. (8 refs).

  12. The Kuramoto model of coupled oscillators with a bi-harmonic coupling function

    E-Print Network [OSTI]

    M. Komarov; A. Pikovsky

    2014-04-29T23:59:59.000Z

    We study synchronization in a Kuramoto model of globally coupled phase oscillators with a bi-harmonic coupling function, in the thermodynamic limit of large populations. We develop a method for an analytic solution of self-consistent equations describing uniformly rotating complex order parameters, both for single-branch (one possible state of locked oscillators) and multi-branch (two possible values of locked phases) entrainment. We show that synchronous states coexist with the neutrally linearly stable asynchronous regime. The latter has a finite life time for finite ensembles, this time grows with the ensemble size as a power law.

  13. Spin-phonon interactions of multiferroic Bi{sub 4}Ti{sub 3}O{sub 12}-BiFeO{sub 3} ceramics: Low-temperature Raman scattering and infrared reflectance spectra investigations

    SciTech Connect (OSTI)

    Jiang, P. P.; Zhang, X. L.; Chang, P.; Hu, Z. G., E-mail: zghu@ee.ecnu.edu.cn; Bai, W.; Li, Y. W.; Chu, J. H. [Department of Electronic Engineering, Key Laboratory of Polar Materials and Devices, Ministry of Education, East China Normal University, Shanghai 200241 (China)

    2014-04-14T23:59:59.000Z

    Optical phonons of multiferroic Bi{sub 4}Ti{sub 3}O{sub 12}-BiFeO{sub 3} ceramic have been investigated by low temperature Raman scattering and infrared reflectance spectra. Anomalies at about 85?K can be observed from the temperature dependence of the Raman and infrared modes, which arise from spin-phonon interaction during antiferromagnetic to paramagnetic phase transition. It was found that the change of exchange interaction in magnetic phase transition can be induced by Fe-O-Fe octahedral tilting driven from the A-site atoms. Moreover, ferroelectricity-related displacement of Bismuth atoms suggests the coupling of magnetic and ferroelectric orders.

  14. Rapid formation of phase-clean 110 K (Bi-2223) powders derived via freeze-drying process

    DOE Patents [OSTI]

    Balachandran, Uthamalingam (Hinsdale, IL)

    1996-01-01T23:59:59.000Z

    A process for the preparation of amorphous precursor powders for Pb-doped Bi.sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.x (2223) includes a freeze-drying process incorporating a splat-freezing step. The process generally includes splat freezing a nitrate solution of Bi, Pb, Sr, Ca, and Cu to form flakes of the solution without any phase separation; grinding the frozen flakes to form a powder; freeze-drying the frozen powder; heating the dried powder to form a dry green precursor powders; denitrating the green-powders; heating the denitrated powders to form phase-clean Bi-2223 powders. The grain boundaries of the 2223 grains appear to be clean, leading to good intergrain contact between 2223 grains.

  15. Rapid liquid phase sintered Mn doped BiFeO{sub 3} ceramics with enhanced polarization and weak magnetization

    SciTech Connect (OSTI)

    Kumar, Manoj; Yadav, K. L. [Smart Material Research Laboratory, Department of Physics, Indian Institute of Technology, Roorkee-247667 (India)

    2007-12-10T23:59:59.000Z

    Single-phase BiFe{sub 1-x}Mn{sub x}O{sub 3} multiferroic ceramics have been synthesized by rapid liquid phase sintering method to study the influence of Mn substitution on their crystal structure, dielectric, magnetic, and ferroelectric behaviors. From XRD analysis it is seen that Mn substitution does not affect the crystal structure of the BiFe{sub 1-x}Mn{sub x}O{sub 3} system. An enhancement in magnetization was observed for BiFe{sub 1-x}Mn{sub x}O{sub 3} ceramics. However, the ferooelectric hysteresis loops were not really saturated, we observed a spontaneous polarization of 10.23 {mu}C/cm{sup 2} under the applied field of 42 kV/cm and remanent polarization of 3.99 {mu}C/cm{sup 2} for x=0.3 ceramic.

  16. Structural, optical and dielectric property of Co doped Bi{sub 2}Fe{sub 4}O{sub 9}

    SciTech Connect (OSTI)

    Swain, Smita, E-mail: singhanil@nitrkl.ac.in; Mohapatra, S. R., E-mail: singhanil@nitrkl.ac.in; Sahoo, B., E-mail: singhanil@nitrkl.ac.in; Singh, A. K., E-mail: singhanil@nitrkl.ac.in [Department of Physics, National Institute of Technology, Rourkela -769008, Odisha (India)

    2014-04-24T23:59:59.000Z

    Multiferroic Bi{sub 2}Fe{sub 4}O{sub 9} and Co doped Bi{sub 2}Fe{sub 4}O{sub 9} are prepared by solid state route reaction method using bismuth oxide(Bi{sub 2}O{sub 3}), iron oxide(Fe{sub 2}O{sub 3}) and cobalt oxide (Co{sub 3}O{sub 4}). Their structural optical and dielectric properties are studied and compared. X-ray diffraction (XRD) results confirm that there is no change in crystal structure due to Co doping. From dielectric constant measurement we conclude that dielectric constant increases due to Co doping. UV-Visible plot shows due to Co doping bang gap energy increases.

  17. Superconducting epitaxial thin films of CeNi{sub x}Bi{sub 2} with a bismuth square net structure

    SciTech Connect (OSTI)

    Buckow, Alexander; Kupka, Katharina; Retzlaff, Reiner; Kurian, Jose; Alff, Lambert [Institute of Materials Science, Technische Universitaet Darmstadt, 64287 Darmstadt (Germany)

    2012-10-15T23:59:59.000Z

    We have grown highly epitaxial and phase pure thin films of the arsenic-free pnictide compound CeNi{sub x}Bi{sub 2} on (100) MgO substrates by reactive molecular beam epitaxy (RMBE). X-ray diffraction and reflection high-energy electron diffraction of the films confirm the ZrCuSiAs structure with a Bi square net layer. Superconductivity was observed in magnetization and resistivity measurements for x= 0.75 to 0.93 in these CeNi{sub x}Bi{sub 2} thin films with the highest critical temperature of 4.05 K and a resistive transition width of 0.1 K for x= 0.86. Our results indicate that thin film deposition by RMBE provides a tool to synthesize high-quality pnictide superconductors of the novel 112 type.

  18. Rapid formation of phase-clean 110 K (Bi-2223) powders derived via freeze-drying process

    DOE Patents [OSTI]

    Balachandran, U.

    1996-06-04T23:59:59.000Z

    A process for the preparation of amorphous precursor powders for Pb-doped Bi{sub 2}Sr{sub 2} Ca{sub 2}Cu{sub 3}O{sub x} (2223) includes a freeze-drying process incorporating a splat-freezing step. The process generally includes splat freezing a nitrate solution of Bi, Pb, Sr, Ca, and Cu to form flakes of the solution without any phase separation; grinding the frozen flakes to form a powder; freeze-drying the frozen powder; heating the dried powder to form a dry green precursor powders; denitrating the green-powders; heating the denitrated powders to form phase-clean Bi-2223 powders. The grain boundaries of the 2223 grains appear to be clean, leading to good intergrain contact between 2223 grains. 11 figs.

  19. Application of bi-linear loglog SN model to strain-controlled fatigue data of aluminum alloys and its effect on life predictions

    E-Print Network [OSTI]

    Fatemi, Ali

    Application of bi-linear log­log S­N model to strain-controlled fatigue data of aluminum alloys­log model is applied to stress amplitude versus fatigue life data of 14 aluminum alloys. It is shown-life curves are discussed. Life predictions of aluminum alloys based on linear and bi-linear models are also

  20. Third-order optical nonlinear absorption in Bi1.95La1.05TiNbO9 thin films Hengzhi Chen a

    E-Print Network [OSTI]

    Cao, Wenwu

    Third-order optical nonlinear absorption in Bi1.95La1.05TiNbO9 thin films Hengzhi Chen a , Bin Yang online 1 June 2010 Keywords: Nonlinear optical absorption Bi1.95La1.05TiNbO9 Optical properties Single absorption coefficient were obtained by optical transmittance measurements. The film exhibits a high

  1. Round wire fabricated with the high temperature superconductor Bi-2212 exhibits a zero resistance to an extremely high magnetic field (beyond 100 T)

    E-Print Network [OSTI]

    hydrogen and carbon cause gas bubbles in the Bi-2212 filaments during heat treatment (top figure), severely bubble formation in the Bi-2212 filaments and raises the conductor transport critical current density Jc-2212 filament showing bubble formation problem that is now solved by over-pressure heat treatment

  2. IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 42, NO. 9, SEPTEMBER 2007 1821 Design and Scaling of W-Band SiGe BiCMOS VCOs

    E-Print Network [OSTI]

    Voinigescu, Sorin Petre

    -Band SiGe BiCMOS VCOs Sean T. Nicolson, Kenneth H. K. Yau, Student Member, IEEE, Pascal Chevalier, Member in two generations of SiGe BiCMOS technology, with MOS and HBT varactors, and with integrated inductors be used to monitor the mm-wave noise performance of SiGe HBTs. Mea- surements show a 106 GHz VCO operating

  3. Al-doped ZnO inverse opal networks as efficient electron collectors in BiVO4 photoanodes for solar

    E-Print Network [OSTI]

    Steiner, Ullrich

    Al-doped ZnO inverse opal networks as efficient electron collectors in BiVO4 photoanodes for solar-doped ZnO inverse opal network is introduced into a BiVO4 photoanode. The conductive inverse opal network of photogenerated charge carriers limits the performance of photoelectrodes for solar water splitting. To reduce

  4. Electron microscopy analyses and electrical properties of the layered Bi{sub 2}WO{sub 6} phase

    SciTech Connect (OSTI)

    Taoufyq, A. [Institut Matériaux Microélectronique et Nanosciences de Provence, IM2NP, UMR CNRS 7334, Université du Sud Toulon-Var, BP 20132, 83957, La Garde Cedex (France); Laboratoire Matériaux et Environnement LME, Faculté des Sciences, Université Ibn Zohr, BP 8106, Cité Dakhla, Agadir, Maroc (Morocco); Département d‘Études des Réacteurs, Laboratoire Dosimétrie Capteurs Instrumentation, CEA Cadarache (France); Société CESIGMA—Signals and Systems, 1576 Chemin de La Planquette, F 83 130 LA GARDE (France); Ait Ahsaine, H. [Laboratoire Matériaux et Environnement LME, Faculté des Sciences, Université Ibn Zohr, BP 8106, Cité Dakhla, Agadir, Maroc (Morocco); Patout, L. [Institut Matériaux Microélectronique et Nanosciences de Provence, IM2NP, UMR CNRS 7334, Université du Sud Toulon-Var, BP 20132, 83957, La Garde Cedex (France); Benlhachemi, A.; Ezahri, M. [Laboratoire Matériaux et Environnement LME, Faculté des Sciences, Université Ibn Zohr, BP 8106, Cité Dakhla, Agadir, Maroc (Morocco); and others

    2013-07-15T23:59:59.000Z

    The bismuth tungstate Bi{sub 2}WO{sub 6} was synthesized using a classical coprecipitation method followed by a calcination process at different temperatures. The samples were characterized by X-ray diffraction, simultaneous thermogravimetry and differential thermal analysis (TGA/DTA), scanning and transmission electron microscopy (SEM, TEM) analyses. The Rietveld analysis and electron diffraction clearly confirmed the Pca2{sub 1} non centrosymmetric space group previously proposed for this phase. The layers Bi{sub 2}O{sub 2}{sup 2+} and WO{sub 4}{sup 2?} have been directly evidenced from the HRTEM images. The electrical properties of Bi{sub 2}WO{sub 6} compacted pellets systems were determined from electrical impedance spectrometry (EIS) and direct current (DC) analyses, under air and argon, between 350 and 700 °C. The direct current analyses showed that the conduction observed from EIS analyses was mainly ionic in this temperature range, with a small electronic contribution. Electrical change above the transition temperature of 660 °C is observed under air and argon atmospheres. The strong conductivity increase observed under argon is interpreted in terms of formation of additional oxygen vacancies coupled with electron conduction. - Graphical abstract: High resolution transmission electron microscopy: inverse fast Fourier transform giving the layered structure of the Bi{sub 2}WO{sub 6} phase, with a representation of the cell dimensions (b and c vectors). The Bi{sub 2}O{sub 2}{sup 2+} and WO{sub 4}{sup 2?} sandwiches are visible in the IFFT image. - Highlights: • Using transmission electron microscopy, we visualize the layered structure of Bi{sub 2}WO{sub 6}. • Electrical analyses under argon gas show some increase in conductivity. • The phase transition at 660 °C is evidenced from electrical modification.

  5. Evidence of improved ferroelectric phase stabilization in Nd and Sc co-substituted BiFeO{sub 3}

    SciTech Connect (OSTI)

    Durga Rao, T.; Asthana, Saket, E-mail: asthanas@iith.ac.in [Advanced Functional Materials Laboratory, Department of Physics, Indian Institute of Technology Hyderabad, Telangana 502205 (India)

    2014-10-28T23:59:59.000Z

    Polycrystalline BiFeO{sub 3} and Bi{sub 0.9}Nd{sub 0.1}Fe{sub 1?x}Sc{sub x}O{sub 3} (x?=?0, 0.05, and 0.10) multiferroic compounds were prepared using conventional solid-state route. X-ray diffraction studies and Raman measurements indicated that the compounds were crystallized in rhombohedral structure with R3c space group. Weak ferromagnetism was induced due to the suppression of canted spin structure in the substituted compounds. Both remanent magnetization (M{sub r}) and coercive field (H{sub c}) were enhanced in Nd and Sc substituted compounds. Further, Néel temperature T{sub N} was decreased from 644?K for BiFeO{sub 3} to 550?K for Bi{sub 0.9}Nd{sub 0.1}Fe{sub 0.9}Sc{sub 0.1}O{sub 3} compound due to weakening of magnetic exchange interactions between B-site cations in the substituted compounds. Enhanced and nearly well saturated electrical polarizations were observed in Sc substituted compounds, which are attributed to the strengthening of covalent hybridization between Bi and O ions and reduction in oxygen vacancies. The remnant polarization was enhanced to 12.5??C/cm{sup 2} in Bi{sub 0.9}Nd{sub 0.1}Fe{sub 0.9}Sc{sub 0.1}O{sub 3} compound. Impedance studies revealed that insulating character of substituted compounds is enhanced and electrical relaxations are of non-Debye type.

  6. BiFeO3 Domain Wall Energies and Structures: A Combined Experimental and Density Functional Theory+U Study

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

    Wang, Yi; Nelson, Chris; Melville, Alexander; Winchester, Benjamin; Shang, Shunli; Liu, Zi-Kui; Schlom, Darrell G.; Pan, Xiaoqing; Chen, Long-Qing

    2013-06-01T23:59:59.000Z

    We determined the atomic structures and energies of 109°, 180°, and 71° domain walls in BiFeO3, combining density functional theory+U calculations and aberration-corrected transmission electron microscopy images. We find a substantial Bi sublattice shift and a rather uniform Fe sublattice across the walls. The calculated wall energies (?) follow the sequence ?109 180 71 for the 109°, 180°, and 71° walls. We attribute the high 71° wall energy to an opposite tilting rotation of the oxygen octahedra and the low 109° wall energy to the opposite twisting rotation of the oxygen octahedra across the domain walls.

  7. Ann bay lodyans 13 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    apral fe le sa a, papa? Papa: Le sa a, se Pari, se manje nan gran restoran, se bwe chanpay, se bel fanm! Pitit: Men, si boul la pa tonbe, papa? Papa: Le sa a, pitit mwen, se lakay, se kasav, se kleren, se manman ou. 8 PAPIYON AK DEMWAZEL Se te... li pre yon fie jon. Tet li foure nan ke fie a, li t ap bwe lawouze ladann, li t ap souse ti poud jon lan. Ti papiyon an te leje, le a te pi leje pase I. Ti papiyon an t ap bat zel li. L6 li fin bwe jouk tan tet li vire ak tout like I te bwe nan...

  8. Solar internal sound speed as inferred from combined BiSON and LOWL oscillation frequencies

    E-Print Network [OSTI]

    Sarbani Basu; W. J. Chaplin; J. Christensen-Dalsgaard; Y. Elsworth; G. R. Isaak; R. New; J. Schou; M. J. Thompson; S. Tomczyk

    1997-02-12T23:59:59.000Z

    Observations of the Sun with the LOWL instrument provide a homogeneous set of solar p-mode frequencies from low to intermediate degree which allows one to determine the structure of much of the solar interior avoiding systematic errors that are introduced when different data sets are combined, i.e., principally the effects of solar cycle changes on the frequencies. Unfortunately, the LOWL data set contains very few of the lowest-degree modes, which are essential for determining reliably the structure of the solar core - in addition, these lowest-degree data have fairly large associated uncertainties. However, observations made by the Birmingham Solar-Oscillations Network (BiSON) in integrated sunlight provide high-accuracy measurements of a large number of low-degree modes. In this paper we demonstrate that the low-degree mode set of the LOWL data can be successfully combined with the more accurate BiSON data, provided the observations are contemporaneous for those frequencies where the solar-cycle-induced effects are important. We show that this leads to a factor-of-two decrease in the error on the inferred sound speed in the solar core. We find that the solar sound speed is higher than in solar models for r < 0.2Rsun. The density of the solar core is, however, lower than that in solar models.

  9. Progress in superconducting performance of rolled multifilamentary Bi-2223 HTS composite conductors

    SciTech Connect (OSTI)

    Li, Q.; Riley, G.N. Jr.; Parrella, R.D. [American Superconductor Corp., Westborough, MA (United States)] [and others

    1996-12-01T23:59:59.000Z

    Significant enhancements in critical current densities in rolled multifilamentary Bi-2223 HTS composite conductors have been achieved using the powder-in-tube technique. At 77 K and self field, oxide critical current densities (J{sub c})of 55 kA/cm{sup 2}, overall or engineering critical current densities of 15 kA/cm{sup 2}, and critical currents of 125 A have been achieved in different rolled multifilamentary composites. Progress in achieving such high electrical performance is believed to stem in part from an improvement of grain connectivity by reducing weak links. The J{sub c} dependence on magnetic field and the degree of c-axis texture of these high quality conductors have been investigated at various temperatures. Our results also demonstrate that the critical current retention in magnetic field can be independently controlled from the self field critical current density, suggesting that flux pinning improvements and weak link reductions can be separately engineered into Bi-2223 composites fabricated using manufacturable processes.

  10. Pushing the Theoretical Limit of Li-CFx Batteries: A Tale of Bi-functional Electrolyte

    SciTech Connect (OSTI)

    Rangasamy, Ezhiylmurugan [ORNL] [ORNL; Li, Juchuan [ORNL] [ORNL; Sahu, Gayatri [ORNL] [ORNL; Dudney, Nancy J [ORNL] [ORNL; Liang, Chengdu [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    In a typical battery, electrodes deliver capacities less or equal the theoretical maxima of the electrode materials.1 The inert electrolyte functions solely as the ionic conductor without contribution to the cell capacity because of its distinct mono-function in the concept of conventional batteries. Here we demonstrate that the most energy-dense Li-CFx battery2 delivers a capacity exceeding the theoretical maximum of CFx with a solid electrolyte of Li3PS4 (LPS) that has dual functions: as the inert electrolyte at the anode and the active component at the cathode. Such a bi-functional electrolyte reconciles both inert and active characteristics through a synergistic discharge mechanism of CFx and LPS. Li3PS4 is known as an inactive solid electrolyte with a broad electrochemical window over 5 V.3 The synergy at the cathode is through LiF, the discharge product of CFx, which activates the electrochemical discharge of LPS at a close electrochemical potential of CFx. Therefore, the solid-state Li-CFx batteries output 126.6% energy beyond their theoretic limits without compromising the stability of the cell voltage. The extra energy comes from the electrochemical discharge of LPS, the inert electrolyte. This bi-functional electrolyte revolutionizes the concept of conventional batteries and opens a new avenue for the design of batteries with an unprecedentedly high energy density.

  11. Metal-semiconductor-transition observed in Bi{sub 2}Ca(Sr, Ba){sub 2}Co{sub 2}O{sub 8+?} single crystals

    SciTech Connect (OSTI)

    Dong, Song-Tao [National Laboratory of Solid State Microstructures and Department of Material Science and Engineering, Nanjing University, Nanjing 210093 (China); Institute of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Zhang, Bin-Bin; Zhang, Lun-Yong; Yao, Shu-Hua, E-mail: ybchen@nju.edu.cn, E-mail: shyao@nju.edu.cn; Zhou, Jian; Zhang, Shan-Tao; Gu, Zheng-Bin; Chen, Yan-Feng [National Laboratory of Solid State Microstructures and Department of Material Science and Engineering, Nanjing University, Nanjing 210093 (China); Chen, Y. B., E-mail: ybchen@nju.edu.cn, E-mail: shyao@nju.edu.cn [National Laboratory of Solid State Microstructures and Department of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China)

    2014-07-28T23:59:59.000Z

    Electrical property evolution of Bi{sub 2}AE{sub 2}Co{sub 2}O{sub 8+?} single crystals (AE?=?Ca, Sr and Ba) is systematically explored. When AE changes from Ca to Ba, the electrical property of Bi{sub 2}Ca{sub 2}Co{sub 2}O{sub 8+?} and Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} demonstrates semiconductor-like properties. But Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} shows the metallic behavior. Analysis of temperature-dependent resistance substantiates that from metallic Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} to semiconductor-like Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} can be attributed to Anderson localization. However the semiconductor behaviour of Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} and Bi{sub 2}Ca{sub 2}Co{sub 2}O{sub 8+?} is related to electronic correlations effect that is inferred by large negative magnetoresistance (?70%). The theoretical electronic structures and valence X-ray photoemission spectroscopy substantiate that there is a relative large density of state around Fermi level in Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} compared with other two compounds. It suggests that Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} is more apt to be metal in this material system.

  12. Thermal Processing Effects on Microstructure and Composition of Cu3SbSe3

    SciTech Connect (OSTI)

    Majsztrik, Paul W [ORNL; Kirkham, Melanie J [ORNL; Garcia Negron, Valerie [Polytechnic University of Puerto Rico (PUPR); Lara-Curzio, Edgar [ORNL; Skoug, Eric [Michigan State University, East Lansing; Morelli, Donald [Michigan State University, East Lansing

    2013-01-01T23:59:59.000Z

    We report on the effects of thermal processing on the microstructure and composition of a system with overall stoichiometry of 3Cu:1Sb:3Se with the aim of producing single-phase Cu3SbSe3. It was found that slowly cooling from the melt produced a multiphase material consisting of Cu2Se and CuSbSe2, but devoid of Cu3SbSe3. Cooling rapidly from the melt resulted in three-phase microstructures consisting of Cu2Se, CuSbSe2, and Cu3SbSe3. Subsequent annealing of the three-phase material between 325 C and 400 C shifted composition towards nearly pure Cu3SbSe3, the target compound of this work. The kinetics of the transformation into Cu3SbSe3 is successfully described using a modified Avrami model, which suggests that diffusion is the rate-controlling step. Values of Young s modulus and hardness, obtained by nanoindentation, are reported for Cu2Se, CuSbSe2, and Cu3SbSe3.

  13. Superconducting and magneto-transport properties of BiS{sub 2} based superconductor PrO{sub 1-x}F{sub x}BiS{sub 2} (x?=?0 to 0.9)

    SciTech Connect (OSTI)

    Jha, Rajveer; Kishan, Hari; Awana, V. P. S., E-mail: awana@mail.npindia.org [CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012 (India)

    2014-01-07T23:59:59.000Z

    We report superconducting properties of PrO{sub 1-x}F{sub x}BiS{sub 2} compounds, synthesized by the vacuum encapsulation technique. The synthesized PrO{sub 1-x}F{sub x}BiS{sub 2} (x?=?0.1, 0.3, 0.5, 0.7, and 0.9) samples are crystallized in a tetragonal P4/nmm space group. Both transport and DC magnetic susceptibility measurements showed bulk superconductivity below 4?K. The maximum T{sub c} is obtained for x?=?0.7 sample. Under applied magnetic field, both T{sub c}{sup onset} and T{sub c} (??=?0) decrease to lower temperatures. We estimated highest upper critical field [H{sub c2}(0)] for PrO{sub 0.3}F{sub 0.7}BiS{sub 2} sample to be above 4?T (Tesla). The thermally activated flux flow activation energy (U{sub 0}) is estimated 54.63?meV in 0.05 T field for PrO{sub 0.3}F{sub 0.7}BiS{sub 2} sample. Hall measurement results showed that electron charge carriers are the dominating ones in these compounds. Thermoelectric effects (Thermal conductivity and Seebeck coefficient) data suggest strong electron-electron correlations in this material.

  14. Effect of excess Bi2O3 on the ferroelectric properties of SrBi2Ta2O9 Jung-Kun Lee, Byungwoo Park, Kug-Sun Honga)

    E-Print Network [OSTI]

    Park, Byungwoo

    , Byungwoo Park, Kug-Sun Honga) School of Materials Science and Engineering, Seoul National University, Seoul such as spontaneous polarization (Ps) showed a dependence on Bi content. The ferroelectric Curie temperature Tc In addition, comprehensive structural studies of layered compounds have shown disorder in the distribution

  15. ENG ME/EC/SE 701: Optimal and robust control Fall 2011 ENG ME/EC/SE 701: Optimal and Robust Control, Fall 2011

    E-Print Network [OSTI]

    emphases given on the optimal control portion. Under optimal control, topics will include the linear-domain (or classical) control (at the level of ME 404) and linear system theory (at the level of ME 501ENG ME/EC/SE 701: Optimal and robust control Fall 2011 ENG ME/EC/SE 701: Optimal and Robust Control

  16. ENG EC/ME/SE 543 Sustainable Power Systems Page 1/5 ENG EC/ME/SE 543 Sustainable Power Systems: Planning, Operation, and Markets

    E-Print Network [OSTI]

    Lin, Xi

    ENG EC/ME/SE 543 Sustainable Power Systems Page 1/5 Syllabus ENG EC/ME/SE 543 Sustainable Power considers key technical and economic characteristics of power systems and presents their interaction.e., the safeguard of security and stability in today's complex power systems. Course Overview We review the key

  17. ENG EC/ME/SE 543 Sustainable Power Systems Page 1/4 ENG EC/ME/SE 543 Sustainable Power Systems: Planning, Operation, and Markets

    E-Print Network [OSTI]

    ENG EC/ME/SE 543 Sustainable Power Systems Page 1/4 Syllabus ENG EC/ME/SE 543 Sustainable Power of power systems and presents their interaction in the design and operation of markets that foster's complex power systems. Course Overview We review the key characteristics of Electric Power Transmission

  18. ENG EC/ME/SE 543 Sustainable Power Systems Page 1/5 ENG EC/ME/SE 543 Sustainable Power Systems: Planning, Operation, and Markets

    E-Print Network [OSTI]

    ENG EC/ME/SE 543 Sustainable Power Systems Page 1/5 Syllabus ENG EC/ME/SE 543 Sustainable Power. Under this premise, the course considers key technical and economic characteristics of power systems efficiency while allowing for the safeguard of security and stability in today's complex power systems

  19. ENG EC/ME/SE 543 Sustainable Power Systems Page 1/5 ENG EC/ME/SE 543 Sustainable Power Systems: Planning, Operation, and Markets

    E-Print Network [OSTI]

    ENG EC/ME/SE 543 Sustainable Power Systems Page 1/5 Syllabus ENG EC/ME/SE 543 Sustainable Power of power systems and presents their interaction in the design and operation of markets that foster systems. Course Overview We review the key characteristics of Electric Power Transmission and Distribution

  20. S bi l f d h d dSystems biology software, data exchange standards and ontologies

    E-Print Network [OSTI]

    Rostock, Universität

    exchange formats o XML based standards o Standards for graphical representation 3. Ontologies (Gene formats o XML based standards o Standards for graphical representation 3. Ontologies (Gene Ontology) 4S bi l f d h d dSystems biology software, data exchange standards and ontologies Ulf Schmitz04 01

  1. The photocatalysis of Bi{sub 2}MoO{sub 6} under the irradiation of blue LED

    SciTech Connect (OSTI)

    Sun, Yuanyuan; Wang, Wenzhong, E-mail: wzwang@mail.sic.ac.cn; Zhang, Ling; Sun, Songmei

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • ·OH trap and hole sink were involved to investigate the active radicals. • Holes play a more important role in the degradation of RhB. • The ·OH were related to the decomposition of phenol. • The ·O{sub 2}-played a leading role in the photodegradation of phenol. • Blue LED is competitive and promising alternative for the future application. - Abstract: Bi{sub 2}MoO{sub 6} has been reported as a promising photocatalyst in wastewater treatment. The active radicals generated over the Bi{sub 2}MoO{sub 6} during the photocatalytic process were thought to be hydroxyl radical (·OH) but have not been proved. Herein, Bi{sub 2}MoO{sub 6} with nanoplate like morphology was synthesized and its photocatalytic performances in the degradation of rhodamine B (RhB) and phenol as colored and colorless model pollutants respectively were evaluated under the irradiation of blue light emitting diode (LED). The tert-butyl alcohol (TBA) as a ·OH trap and ethylene diamine tetraacetic acid (EDTA) as a hole sink were involved to investigate the main active groups that are generated on Bi{sub 2}MoO{sub 6} and function during the photodegradation of RhB and phenol. In addition, it is a competitive and promising alternative plan to use blue LED as light source for the future practical application in environmental remediation.

  2. A 16 mm3 autonomous solar-powered sensor node with bi-directional optical communication for distributed sensor net-

    E-Print Network [OSTI]

    Kahn, Joseph M.

    Abstract A 16 mm3 autonomous solar-powered sensor node with bi- directional optical communication, a 2.6 mm2 SOI solar cell array, and a micromachined four-quadrant corner-cube retroreflector (CCR- idly deployed by unmanned aerial vehicles (UAV), tracking the movements of birds, small animals

  3. Bi-Annual Scientific Report Jan. 2002 -Dec. 2003 Department of Solar Energy & Environmental Physics: highlight of research projects.

    E-Print Network [OSTI]

    Prigozhin, Leonid

    Bi-Annual Scientific Report Jan. 2002 - Dec. 2003 Department of Solar Energy & Environmental by the researchers of the Department of Solar Energy & Environmental Physics during the reported years provides a wide scope of environmental physics problems and their treatment calls for the application of a large

  4. Performance of Titanium-Oxide/Polymer Insulation in Bi-2212/Ag-alloy Round Wire Wound Superconducting Coils

    E-Print Network [OSTI]

    Peng Chen; Ulf P Trociewitz; Matthieu Dalban-Canassy; Jianyi Jiang; Eric E Hellstrom; David C Larbalestier

    2013-03-20T23:59:59.000Z

    Conductor insulation is one of the key components needed to make Ag-alloy clad Bi2Sr2CaCu2O8+x (Bi-2212/Ag) superconducting round wire (RW) successful for high field magnet applications as dielectric standoff and high winding current densities (Jw) directly depend on it. In this study, a TiO2/polymer insulation coating developed by nGimat LLC was applied to test samples and a high field test coil. The insulation was investigated by differential thermal analysis (DTA), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), dielectric properties measurement, and transport critical current (Ic) properties measurement. About 29% of the insulation by weight is polymer. When the Bi-2212/Ag wire is full heat treated, this decomposes with slow heating to 400{\\deg}C in pure O2. After the full reaction, we found that the TiO2 did not degrade the critical current properties, adhered well to the conductor, and provided a breakdown voltage of >100 V, which allowed the test coil to survive quenching in 31.2 T background field, while providing a 2.6 T field increment. For Bi-2212/Ag RW with a typical diameter of 1.0-1.5 mm, this ~15 um thick insulation allows a very high coil packing factor of ~0.74, whereas earlier alumino-silicate braid insulation only allows packing factors of 0.38-0.48.

  5. Surface states and topological invariants in three-dimensional topological insulators: Application to Bi1-xSbx

    E-Print Network [OSTI]

    Kane, Charles

    Surface states and topological invariants in three-dimensional topological insulators: Application Brillouin zone. This confirms that the alloy is a strong topological insulator in the 1;111 Z2 topological the surface states. We show that the sign of nM in the topological insulator phase of Bi1-xSbx is related

  6. Predicting error in detecting mammographic masses among radiology trainees using statistical models based on BI-RADS features

    SciTech Connect (OSTI)

    Grimm, Lars J., E-mail: Lars.grimm@duke.edu; Ghate, Sujata V.; Yoon, Sora C.; Kim, Connie [Department of Radiology, Duke University Medical Center, Box 3808, Durham, North Carolina 27710 (United States)] [Department of Radiology, Duke University Medical Center, Box 3808, Durham, North Carolina 27710 (United States); Kuzmiak, Cherie M. [Department of Radiology, University of North Carolina School of Medicine, 2006 Old Clinic, CB No. 7510, Chapel Hill, North Carolina 27599 (United States)] [Department of Radiology, University of North Carolina School of Medicine, 2006 Old Clinic, CB No. 7510, Chapel Hill, North Carolina 27599 (United States); Mazurowski, Maciej A. [Duke University Medical Center, Box 2731 Medical Center, Durham, North Carolina 27710 (United States)] [Duke University Medical Center, Box 2731 Medical Center, Durham, North Carolina 27710 (United States)

    2014-03-15T23:59:59.000Z

    Purpose: The purpose of this study is to explore Breast Imaging-Reporting and Data System (BI-RADS) features as predictors of individual errors made by trainees when detecting masses in mammograms. Methods: Ten radiology trainees and three expert breast imagers reviewed 100 mammograms comprised of bilateral medial lateral oblique and craniocaudal views on a research workstation. The cases consisted of normal and biopsy proven benign and malignant masses. For cases with actionable abnormalities, the experts recorded breast (density and axillary lymph nodes) and mass (shape, margin, and density) features according to the BI-RADS lexicon, as well as the abnormality location (depth and clock face). For each trainee, a user-specific multivariate model was constructed to predict the trainee's likelihood of error based on BI-RADS features. The performance of the models was assessed using area under the receive operating characteristic curves (AUC). Results: Despite the variability in errors between different trainees, the individual models were able to predict the likelihood of error for the trainees with a mean AUC of 0.611 (range: 0.502–0.739, 95% Confidence Interval: 0.543–0.680,p < 0.002). Conclusions: Patterns in detection errors for mammographic masses made by radiology trainees can be modeled using BI-RADS features. These findings may have potential implications for the development of future educational materials that are personalized to individual trainees.

  7. Effect of diamagnetic barium substitution on magnetic and photovoltaic properties in multiferroic BiFeO{sub 3}

    SciTech Connect (OSTI)

    Hung, C.-M. [Graduate Institute of Applied Science and Engineering, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China); Tu, C. S., E-mail: 039611@mail.fju.edu.tw [Graduate Institute of Applied Science and Engineering, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China); Department of Physics, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China); Xu, Z.-R.; Chang, L.-Y. [Department of Physics, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China); Schmidt, V. H.; Chien, R. R. [Department of Physics, Montana State University, Bozeman, Montana 59717 (United States); Chang, W. C. [Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China)

    2014-05-07T23:59:59.000Z

    Spontaneous magnetization and photovoltaic (PV) effects have been measured in (Bi{sub 1-x}Ba{sub x})FeO{sub 3-?} ceramics for x?=?0.05, 0.10, and 0.15. The substitution of Ba{sup 2+} ion in the A site of the perovskite unit cell can effectively enhance the ferromagnetic magnetization. The heterostructure of indium tin oxide (ITO) film/(Bi{sub 1-x}Ba{sub x})FeO{sub 3-?} ceramic/Au film exhibits significant PV effects under illumination of ??=?405?nm. The PV responses decrease with increasing Ba concentration. The maximum power-conversion efficiency in the ITO/(Bi{sub 0.95}Ba{sub 0.5})FeO{sub 2.95}/Au can reach 0.006%. A theoretical model based on optically excited current in the depletion region between ITO film and (Bi{sub 1-x}Ba{sub x})FeO{sub 3-?} ceramics is used to describe the I-V characteristic, open-circuit voltage (V{sub oc}), and short-circuit current density (J{sub sc}) as a function of light intensity.

  8. A BiCriteria Scheduling Heuristics for Distributed Embedded Systems under Reliability and RealTime Constraints

    E-Print Network [OSTI]

    Girault, Alain

    A Bi­Criteria Scheduling Heuristics for Distributed Embedded Systems under Reliability and Real are met. Keywords: Distributed real­time systems, safety­critical systems, reliability, multi­time distributed systems in the literature do not attempt to introduce reliability; rather, they concentrate

  9. A Bi-Criteria Scheduling Heuristics for Distributed Embedded Systems under Reliability and Real-Time Constraints

    E-Print Network [OSTI]

    Girault, Alain

    A Bi-Criteria Scheduling Heuristics for Distributed Embedded Systems under Reliability and Real are met. Keywords: Distributed real-time systems, safety-critical systems, reliability, multi-time distributed systems in the literature do not attempt to introduce reliability; rather, they concentrate

  10. Coronal Response of Bi-directional Jets Armagh Observatory, College Hill, Armagh BT61 9DG, N. Ireland

    E-Print Network [OSTI]

    of phenomena charac- terizing the solar transition region. Using simultaneously obtained SUMER obser- vations the wider frame-work of the upper solar atmosphere is still uncertain. These dynamic events were #12;rst counterparts to bi-directional jets were presented by Dere (1994), Moses & Cook (1994) and Teriaca, Madjarska

  11. Mechanisms of the Wurtzite to Rocksalt Transformation in CdSe Nanocrystals Michael Grunwald,1

    E-Print Network [OSTI]

    Rabani, Eran

    Mechanisms of the Wurtzite to Rocksalt Transformation in CdSe Nanocrystals Michael Gru¨nwald,1 Eran transition from the four-coordinate wurtzite to the six-coordinate rocksalt structure in CdSe nanocrystals wurtzite structure to the six-coordinate rocksalt structure in CdSe is strongly influenced by crystal size

  12. DISSERTATION ANTICIPATED PERFORMANCE OF Cu(In,Ga)Se2 SOLAR CELLS IN THE

    E-Print Network [OSTI]

    Sites, James R.

    i DISSERTATION ANTICIPATED PERFORMANCE OF Cu(In,Ga)Se2 SOLAR CELLS IN THE THIN-FILM LIMIT Submitted ENTITLED `ANTICIPATED PERFORMANCE OF Cu(In,Ga)Se2 SOLAR CELLS IN THE THIN-FILM LIMIT' BE ACCEPTED(In,Ga)Se2 SOLAR CELLS IN THE THIN-FILM LIMIT The demand for alternative sources of energy is rapidly

  13. Cu(In,Ga)Se2based Photovoltaics: Challenges and Opportunities

    E-Print Network [OSTI]

    Firestone, Jeremy

    % Different companies, processes, substrates Substrate Mo Cu(InGa)Se2 buffer TCO Cu(InGa)Se2 Solar Cells #12-evaporation using 3-stage process (ZSW, NREL) Reaction of sputtered precursors (Solar Frontier) From pilot; High optical absorption Unique properties for solar cells Compositional tolerance Cu(InGa)Se2 Thin

  14. DISSERTATION DEVICE PHYSICS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS

    E-Print Network [OSTI]

    Sites, James R.

    DISSERTATION DEVICE PHYSICS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS Submitted by Markus Gloeckler PHYSICS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS BE ACCEPTED AS FULFILLING IN PART REQUIREMENTS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS Thin-film solar cells have the potential to be an important

  15. Effect of Dy-substitution on the structural, vibrational, and multiferroic properties of BiFeO{sub 3} nanoparticles

    SciTech Connect (OSTI)

    Muneeswaran, M.; Giridharan, N. V., E-mail: giri@nitt.edu [Advanced Functional Materials Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli 620 015 (India)

    2014-06-07T23:59:59.000Z

    Dysprosium (Dy) modified BiFeO{sub 3} [Bi{sub 1?x}Dy{sub x}FeO{sub 3} (x?=?0.05, 0.10, and 0.15)] nanoparticles have been synthesized by a low temperature co-precipitation method. Rietveld analysis of X-ray diffraction data reveals a transformation from rhombohedral structure to orthorhombic structure with increase in the Dy concentration. From the transmission electron microscopy analysis, it is observed that the particle sizes of Bi{sub 1?x}Dy{sub x}FeO{sub 3} (x?=?0.05, 0.10, and 0.15) nanoparticles range between 50–70, 40–50, and 30–50?nm, respectively. Raman spectra of Bi{sub 1?x}Dy{sub x}FeO{sub 3} (x?=?0.05) belonging to rhombohedral (R3c) structure show 4A{sub 1} and 7E fundamental Raman modes in the range of 100–650?cm{sup ?1} and two-phonon scattering modes such as 2A{sub 4} (longitudinal optical), 2E8 (transverse optical (TO)), and 2E{sub 9} (TO) in the range of 950–1270?cm{sup ?1}. Suppression, broadening, and shifting of Raman modes have been observed with further increase in Dy concentration. The fundamental Raman modes of Bi{sub 1?x}Dy{sub x}FeO{sub 3} (x?=?0.15) are assigned under orthorhombic (pnma) rather than rhombohedral (R3c) as the Rietveld analysis of X-ray diffraction data predicts a structural transformation for this particular composition. A complete suppression of two phonon modes has been noticed for this composition. An anomaly in the temperature dependent dielectric studies has been observed in all the samples at the vicinity of Neel temperature indicating a magnetic ordering, and an increase in magnetization with increase of Dy concentration in BiFeO{sub 3} is noticed from the room temperature magnetic studies. P–E hysteresis loop studies show a decrease of remnant polarization (P{sub r}) with the increase in Dy concentration and disappearance of hysteresis loop occurs for Bi{sub 1?x}Dy{sub x}FeO{sub 3} (x?=?0.15) depicting a transformation from non-centrosymmetric (R3c) to centrosymmetric (Pnma) system.

  16. Microwave-assisted solvothermal synthesis of flower-like Ag/AgBr/BiOBr microspheres and their high efficient photocatalytic degradation for p-nitrophenol

    SciTech Connect (OSTI)

    Li, Tingting, E-mail: tingtingli1983@hotmail.com [Department of Chemistry and Chemical Engineering, Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Changsha 410082 (China); State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Luo, Shenglian, E-mail: sllou@hnu.edu.cn [Department of Chemistry and Chemical Engineering, Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Changsha 410082 (China); State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Yang, Lixia [Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China)

    2013-10-15T23:59:59.000Z

    Flower-like Ag/AgBr/BiOBr microspheres were successfully fabricated by the approach of microwave-assisted solvothermal and in situ photo-assisted reduction. A reactive ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C{sub 16}mim]Br) was employed as Br source in the presence of surfactant polyvinylpyrrolidone (PVP). The photocatalytic activity of Ag/AgBr/BiOBr towards the decomposition of p-nitrophenol under visible light irradiation was evaluated. The results indicated that Ag/AgBr/BiOBr showed enhanced photocatalytic activity towards p-nitrophenol, comparing with P25, BiOBr and Ag/AgBr. More than 96% of p-nitrophenol was decomposed in 3.5 h under visible-light irradation. The excellent photocatalytic activity of flower-like Ag/AgBr/BiOBr microspheres can be attributed to the large specific surface area, strong visible-light absorption, suitable energy band structure and surface plasmon resonance effect of Ag nanoparticles. The possible photocatalytic mechanism was proposed based on the active species test and band gap structure analysis. - Graphical abstract: The photocatalytic reaction mechanisms of the as-prepared Ag/AgBr/BiOBr. Display Omitted - Highlights: • Successful synthesis of flower-like Ag/AgBr/BiOBr microspheres. • The Ag/AgBr/BiOBr showed much higher photocatalytic activity towards p-nitrophenol as compared to BiOBr and Ag/AgBr. • The reasons for the excellent photocatalytic activity are the large specific surface area, strong visible-light absorption and surface plasmon resonance effect of Ag nanoparticles. • The O{sub 2}·{sup ?}, Br{sup 0} and photogenerated h{sup +} play key roles in the photocatalytic degradation process.

  17. Reduced Coercive Field in BiFeO3 Thin Films through Domain Engineering

    SciTech Connect (OSTI)

    Shelke, Vilas K [ORNL] [ORNL; Mazumdar, Dipanjan [ORNL] [ORNL; Srinivasan, Dr. Gopalan [Oakland University, Rochester, MI] [Oakland University, Rochester, MI; Jesse, Stephen [ORNL] [ORNL; Kalinin, Sergei V [ORNL] [ORNL; Baddorf, Arthur P [ORNL] [ORNL; Gupta, Dr. Arunava [University of Alabama, Tuscaloosa] [University of Alabama, Tuscaloosa

    2011-01-01T23:59:59.000Z

    The bismuth ferrite (BiFeO3) material offers a comprehensive package of multifunctionality. In addition to the multiferroic behavior, i.e. coexistence of electric and magnetic orderings,[1] it also exhibits photovoltaic effect, [2] metal-insulator transition,[3] electric modulation of conduction,[4] and terahertz radiation emission.[5] The possibility of joint control of electric, magnetic, and optical properties provides several degrees of freedom to design exotic devices. It is a green energy material in the sense that it is lead-free and energy-efficient due to cryogen-less functionality. Therefore, a wide variety of applications in terms of sensors, memories and spintronic devices are foreseen.[6] However, the incipient lower value of magneto-electric coupling has raised skepticism regarding its multiferroic capabilities and allied applications.[6] Nevertheless, the highest value of ferroelectric polarization (~ 100 C.cm-2) is very promising for next generation ferroelectric random access memory devices.

  18. Terahertz Spectroscopy of Spin Waves in Multiferroic BiFeO3 in High Magnetic Fields

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

    Nagel, U.; Fishman, Randy S.; Katuwal, T.; Engelkamp, H.; Talbayev, D.; Yi, Hee Taek; Cheong, S.-W.; Rőőm, T.

    2013-06-01T23:59:59.000Z

    We have studied the magnetic field dependence of far-infrared active magnetic modes in a single ferroelectric domain BiFeO3 crystal at low temperature. The modes soften close to the critical field of 18.8 T along the [001] (pseudocubic) axis, where the cycloidal structure changes to the homogeneous canted antiferromagnetic state and a new strong mode with linear field dependence appears that persists at least up to 31 T. A microscopic model that includes two Dzyaloshinskii-Moriya interactions and easy-axis anisotropy describes closely both the zero-field spectroscopic modes as well as their splitting and evolution in a magnetic field. The good agreement of theory with experiment suggests that the proposed model provides the foundation for future technological applications of this multiferroic material.

  19. Critical currents of YBCO tapes and Bi-2212 wires at different temperatures and magnetic fields

    SciTech Connect (OSTI)

    Lombardo, V.; Barzi, e.; Turrioni, D.; Zlobin, A.V.; /Fermilab

    2010-08-01T23:59:59.000Z

    Design studies for the cooling channel of a Muon Collider call for straight and helical solenoids generating field well in excess of the critical fields of state of the art Low Temperature Superconductors (LTS) such as Nb{sub 3}Sn or NbTi. Therefore, High Temperature Superconductors (HTS) will need to be used for the manufacturing of all or certain sections of such magnets to be able to generate and withstand the field levels at the cryogenic temperatures required by the new machine. In this work, two major High Temperature Superconductors - Bi2212 round wires and YBCO coated conductor tapes - are investigated to understand how critical current density of such conductors scales as a function of external field and operating temperature. This is vital information to make conductor choices depending on the application and to proceed with the design of such magnets.

  20. Electric field control of magnetism using BiFeO{sub 3}-based heterostructures

    SciTech Connect (OSTI)

    Heron, J. T., E-mail: jth247@cornell.edu [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States); Schlom, D. G. [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States); Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853 (United States); Ramesh, R. [Department of Materials Science and Engineering, University of California, Berkeley, California 94720 (United States); Department of Physics, University of California, Berkeley, California 94720 (United States); Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2014-06-15T23:59:59.000Z

    Conventional CMOS based logic and magnetic based data storage devices require the shuttling of electrons for data processing and storage. As these devices are scaled to increasingly smaller dimensions in the pursuit of speed and storage density, significant energy dissipation in the form of heat has become a center stage issue for the microelectronics industry. By taking advantage of the strong correlations between ferroic orders in multiferroics, specifically the coupling between ferroelectric and magnetic orders (magnetoelectricity), new device functionalities with ultra-low energy consumption can be envisioned. In this article, we review the advances and highlight challenges toward this goal with a particular focus on the room temperature magnetoelectric multiferroic, BiFeO{sub 3}, exchange coupled to a ferromagnet. We summarize our understanding of the nature of exchange coupling and the mechanisms of the voltage control of ferromagnetism observed in these heterostructures.

  1. Rarefaction shock in plasma with a bi-Maxwellian electron distribution function

    SciTech Connect (OSTI)

    Diaw, A.; Mora, P. [Centre de Physique Theorique, Ecole Polytechnique, CNRS, FR-91128 Palaiseau (France)

    2011-09-15T23:59:59.000Z

    The one-dimensional collisionless expansion into a vacuum of a plasma with a bi-Maxwellian electron distribution function and a single ion species is studied both theoretically and numerically. A shock wave occurs when the ratio of the temperatures between the hot and the cold electrons is larger than 5+{radical}(24)[B. Bezzerides, D. W. Forslund, and E. L. Lindman, Phys. Fluids 21, 2179 (1978)]. The theoretical model presented here gives a coherent and complete description of the rarefaction shock and its effects on the ion acceleration process. Analytical expressions of the characteristics of the shock are given. The analytical findings are compared to the results of a hybrid code describing the plasma expansion, and an excellent agreement is obtained.

  2. Thermal-mechanical Properties of Epoxy-impregnated Bi-2212/Ag Composite

    SciTech Connect (OSTI)

    Li, Pei; Wang, Yang; Godeke, Arno; Ye, Liyang; Flanagan, Gene; Shen, Tengming

    2014-11-26T23:59:59.000Z

    Knowledge of the thermal-mechanical properties of epoxy/superconductor/insulation composite is important for designing, fabricating, and operating epoxy impregnated high field superconducting magnets near their ultimate potentials. We report measurements of the modulus of elasticity, Poisson’s ratio, and the coefficient of thermal contraction of epoxy-impregnated composite made from the state-of-the-art powder-in-tube multifilamentary Ag/Bi2Sr2CaCu2Ox round wire at room temperature and cryogenic temperatures. Stress-strain curves of samples made from single-strand and Rutherford cables were tested under both monotonic and cyclic compressive loads, with single strands insulated using a thin TiO2 insulation coating and the Rutherford cable insulated with a braided ceramic sleeve.

  3. Synchronization transitions in ensembles of noisy oscillators with bi-harmonic coupling

    E-Print Network [OSTI]

    Vladimir Vlasov; Maxim Komarov; Arkady Pikovsky

    2014-11-12T23:59:59.000Z

    We describe synchronization transitions in an ensemble of globally coupled phase oscillators with a bi-harmonic coupling function, and two sources of disorder - diversity of intrinsic oscillatory frequencies and external independent noise. Based on the self-consistent formulation, we derive analytic solutions for different synchronous states. We report on various non-trivial transitions from incoherence to synchrony where possible scenarios include: simple supercritical transition (similar to classical Kuramoto model), subcritical transition with large area of bistability of incoherent and synchronous solutions, and also appearance of symmetric two-cluster solution which can coexist with regular synchronous state. Remarkably, we show that the interplay between relatively small white noise and finite-size fluctuations can lead to metastable asynchronous solution.

  4. Observation and Measurement of Se-79 in SRS High-Level Tank Fission Product Waste

    SciTech Connect (OSTI)

    Dewberry, R.A.

    2000-08-21T23:59:59.000Z

    The authors report the first observation of confirmed Se-79 activity in Savannah River Site high level fission product waste. Se-79 was measured after a seven step chemical treatment to remove interfering activity from Cs-137, Sr-90, and plutonium at levels 105 times higher than the observed Se-79 content and to remove Tc-99 at levels 300 times higher than observed Se-79. Se-79 was measured by liquid scintillation beta-decay counting after specific tests to eliminate uncertainties from possible contributions from Tc-99, Pm-147, Sm-151, Zr-93, or Pu-241, whose beta-decay spectra could appear similar to that of Se-79, and whose content would be expected at levels near or greater than Se-79.

  5. Insulin-like Growth Factor-I and Slow, Bi-directional Perfusion Enhance the Formation of Tissue-Engineered Cardiac Grafts

    E-Print Network [OSTI]

    Cheng, Mingyu

    Biochemical and mechanical signals enabling cardiac regeneration can be elucidated using in vitro tissue-engineering models. We hypothesized that insulin-like growth factor-I (IGF) and slow, bi-directional perfusion could ...

  6. Statistical analysis of the electromechanical behavior of AgMg sheathed Bi2Sr2CaCu2O8+x superconducting

    E-Print Network [OSTI]

    American Institute of Physics. DOI: 10.1063/1.2715844 I. INTRODUCTION High temperature superconducting HTS wires and tapes, the failure is associated with the brittle failure of individual Bi2212 filaments

  7. Tissue specific regulation of the high density lipoprotein (HDL) receptor, scavenger receptor Class B, Type I (SR-BI) by the scaffold protein PDZK1

    E-Print Network [OSTI]

    Fenske, Sara Anne

    2008-01-01T23:59:59.000Z

    PDZK1 is a four PDZ-domain containing cytoplasmic adaptor protein that binds the Cterminus of the high-density lipoprotein (HDL) receptor SR-BI. Abolishing PDZK1 expression in PDZK1 knockout (KO) mice leads to a ...

  8. Electrodeposition of ultrathin Pd, Co and Bi films on well-defined noble-metal electrodes: studies by ultrahigh vacuum-electrochemistry (UHV-EC) 

    E-Print Network [OSTI]

    Baricuatro, Jack Hess L

    2006-10-30T23:59:59.000Z

    Three illustrative cases involving the electrodeposition of ultrathin metal films of varying reactivities onto noble-metal substrates were investigated: (i) Pd on Pt(111), a noble admetal on a noble-metal surface; (ii) Bi ...

  9. ADVANCES IN SE-79 ANALYSES ON SAVANNAH RIVER SITE RADIOACTIVE WASTE MATRICES

    SciTech Connect (OSTI)

    Diprete, D; C Diprete, C; Ned Bibler, N; Cj Bannochie, C; Michael Hay, M

    2009-03-16T23:59:59.000Z

    Waste cleanup efforts underway at the United States Department of Energy's (DOE) Savannah River Site (SRS) in South Carolina, as well as other DOE nuclear sites, have created a need to characterize {sup 79}Se in radioactive waste inventories. Successful analysis of {sup 79}Se in high activity waste matrices is challenging for a variety of reasons. As a result of these unique challenges, the successful quantification of {sup 79}Se in the types of matrices present at SRS requires an extremely efficient and selective separation of {sup 79}Se from high levels of interfering radionuclides. A robust {sup 79}Se radiochemical separation method has been developed at the Savannah River National Laboratory (SRNL) which is routinely capable of successfully purifying {sup 79}Se from a wide range of interfering radioactive species. In addition to a dramatic improvements in the Kd, ease, and reproducibility of the analysis, the laboratory time has been reduced from several days to only 6 hours.

  10. Giant strain with ultra-low hysteresis and high temperature stability in grain oriented lead-free K???Bi???TiO?-BaTiO?-Na???Bi???TiO? piezoelectric materials

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

    Maurya, Deepam; Zhou, Yuan; Wang, Yaojin; Yan, Yongke; Li, Jiefang; Viehland, Dwight; Priya, Shashank

    2015-02-26T23:59:59.000Z

    We synthesized grain-oriented lead-free piezoelectric materials in (K???Bi???TiO?-BaTiO?-xNa???Bi???TiO? (KBT-BT-NBT) system with high degree of texturing along the [001]c (c-cubic) crystallographic orientation. We demonstrate giant field induced strain (~0.48%) with an ultra-low hysteresis along with enhanced piezoelectric response (d?? ~ 190pC/N) and high temperature stability (~160°C). Transmission electron microscopy (TEM) and piezoresponse force microscopy (PFM) results demonstrate smaller size highly ordered domain structure in grain-oriented specimen relative to the conventional polycrystalline ceramics. The grain oriented specimens exhibited a high degree of non-180° domain switching, in comparison to the randomly axed ones. These results indicate the effective solution to the lead-free piezoelectricmore »materials.« less

  11. Photovoltaic Devices Employing Ternary PbSxSe1-x Nanocrystals

    SciTech Connect (OSTI)

    Ma, Wanli; Luther, Joseph; Zheng, Haimei; Wu, Yue; Alivisatos, A. Paul

    2009-02-05T23:59:59.000Z

    We report solar cells based on highly confined nanocrystals of the ternary compound PbSxSe1-x. Crystalline, monodisperse alloyed nanocrystals are obtained using a one-pot, hot injection reaction. Rutherford back scattering and energy filtered transmission electron microscopy suggest that the S and Se anions are uniformly distributed in the alloy nanoparticles. Photovoltaic devices made using ternary nanoparticles are more efficient than either pure PbS or pure PbSe based nanocrystal devices.

  12. Pressure-induced phase transformation of In2Se3 Anya M. Rasmussen,1

    E-Print Network [OSTI]

    McCluskey, Matthew

    13 February 2013) In2Se3 has potential as a phase-change material for memory applications and the defect wurtzite c phase.1 Recently, In2Se3 has received attention as a phase-change material that could be used in phase-change random access memory (PRAM) applications.2,3 In2Se3 may be preferable over Ge2Sb2

  13. Synthesis and Crystal Structure Study of 2’-Se-Adenosine-Derivatized DNA

    SciTech Connect (OSTI)

    Sheng, J.; Salon, J; Gan, J; Huang, Z

    2010-01-01T23:59:59.000Z

    The selenium derivatization of nucleic acids is a novel and promising strategy for 3D structure determination of nucleic acids. Selenium can serve as an excellent anomalous scattering center to solve the phase problem, which is one of the two major bottlenecks in macromolecule X-ray crystallography. The other major bottleneck is crystallization. It has been demonstrated that the incorporated selenium functionality at the 2'-positions of the nucleosides and nucleotides is stable and does not cause significant structure perturbation. Furthermore, it was observed that the 2'-Se-derivatization could facilitate crystallization of oligonucleotides with fast crystal growth and high diffraction quality. Herein, we describe a convenient synthesis of the 2'-Se-adenosine phosphoramidite, and report the first synthesis and X-ray crystal structure determination of the DNA containing the 2'-Se-A derivatization. The 3D structure of 2'-Se-A-DNA decamer [5'-GTACGCGT(2'-Se-A)C-3']{sub 2} was determined at 1.75 {angstrom} resolution, the 2'-Se-functionality points to the minor groove, and the Se-modified and native structures are virtually identical. Moreover, we have observed that the 2'-Se-A modification can greatly facilitate the crystal growth with high diffraction quality. In conjunction with the crystallization facilitation by the 2'-Se-U and 2'-Se-T, this novel observation on the 2'-Se-A functionality suggests that the 2'-Se moiety is sole responsible for the crystallization facilitation and the identity of nucleobases does not influence the crystal growth significantly.

  14. arXiv:0710.1988v1[hep-lat]10Oct2007 Deflated BiCGStab for linear equations in QCD

    E-Print Network [OSTI]

    Morgan, Ron

    arXiv:0710.1988v1[hep-lat]10Oct2007 Deflated BiCGStab for linear equations in QCD problems Abdou M. Abdel-Rehim Department of Physics, Baylor University, Waco, TX 76798-7316, USA. E-mail: Abdou-NonCommercial-ShareAlike Licence. http://pos.sissa.it/ #12;Deflated BiCGStab for linear equations in QCD problems Abdou M. Abdel

  15. Development of the ReaxFF reactive force field for mechanistic studies of catalytic selective oxidation processes on BiMoOx

    E-Print Network [OSTI]

    van Duin, Adri

    report the use of ReaxFF to study the activation and conversion of propene to acrolein by various metal acrolein. The propene reations on V2O5 occur at lower temperatures than on Bi2O3 or Bi2Mo3O12. The results-metal­ oxide (MMO) catalysts, accounts for the majority of the 8 billion pounds of acrolein produced annually

  16. High-frequency electromagnetic properties of epitaxial Bi2FeCrO6 thin films grown by pulsed laser deposition

    E-Print Network [OSTI]

    High-frequency electromagnetic properties of epitaxial Bi2FeCrO6 thin films grown by pulsed laser on the electromagnetic (EM) properties in high-frequency domain (HF) of multiferroic Bi2FeCrO6 (BFCO) thin films. The films were epitaxially grown on SrTiO3 substrates by pulsed laser ablation. Typical 50 nm-thick BFCO

  17. SciTech Connect: A Solution for Solution-Produced [beta]-FeSe...

    Office of Scientific and Technical Information (OSTI)

    A Solution for Solution-Produced beta-FeSe: Elucidating and Overcoming Factors that Prevent Superconductivity Citation Details In-Document Search Title: A Solution for...

  18. Photovoltaic Devices Employing Ternary PbSxSe1-x Nanocrystals

    E-Print Network [OSTI]

    Alivisatos, A. Paul

    2009-01-01T23:59:59.000Z

    performance. The x-axis represents composition change from pure PbSe, to pure PbS, versus various photovoltaic

  19. Photovoltaic performance of ultra-small PbSe quantum dots

    E-Print Network [OSTI]

    Ma, Wanli

    2014-01-01T23:59:59.000Z

    Photovoltaic performance of ultra-small PbSe quantum dotssize on the photovoltaic performance of simple Schottky-typeconfinement on the photovoltaic performance, we adopted

  20. Photovoltaic Devices Employing Ternary PbSxSe1-x Nanocrystals

    E-Print Network [OSTI]

    Alivisatos, A. Paul

    2009-01-01T23:59:59.000Z

    Photovoltaic Devices Employing Ternary PbS x Se 1-xalloy nanoparticles. Photovoltaic devices made using ternaryInformation for Efficient Photovoltaic Devices Employing

  1. Photovoltaic performance of ultra-small PbSe quantum dots

    E-Print Network [OSTI]

    Ma, Wanli

    2014-01-01T23:59:59.000Z

    Y; Alivisatos, AP, Photovoltaic Devices Employing TernaryPhotovoltaic performance of ultra-small PbSe quantum dotsquantum dot, solar cell, photovoltaic, quantum size effect

  2. Phase diagram of the CulnSe{sub 2}-CuGaSe{sub 2} pseudobinary system studied by combined ab initio density functional theory and thermodynamic calculation

    SciTech Connect (OSTI)

    Xue, H. T.; Tang, F. L., E-mail: tfl03@mails.tsinghua.edu.cn [State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Department of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050 (China); Science and Technology on Surface Engineering Laboratory, Lanzhou Institute of Physics, Lanzhou 730000 (China); Lu, W. J.; Li, X. K.; Zhang, Y. [State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Department of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050 (China); Feng, Y. D. [Science and Technology on Surface Engineering Laboratory, Lanzhou Institute of Physics, Lanzhou 730000 (China)

    2014-08-07T23:59:59.000Z

    The phase diagram of the CuInSe{sub 2}-CuGaSe{sub 2} pseudobinary system was determined using a combination of special quasirandom structure approach, ab initio density functional theory calculations, and thermodynamic modelling. It is shown that the CuIn{sub 1?x}Ga{sub x}Se{sub 2} solution phase has a tendency to phase separation at low temperature. The calculated consolute temperature is 485?K. It is found that both the binodal and spinodal curves are significantly asymmetric and on both curves there are a local maximum and a local minimum, which have not been reported in the previous studies. Our phase diagram can well explain the finding that the inhomogeneity of CuIn{sub 0.25}Ga{sub 0.75}Se{sub 2} is higher than that of CuIn{sub 0.75}Ga{sub 0.25}Se{sub 2} at the same temperature, while the previous phase diagrams cannot. Hence, our phase diagram should be more reliable and applicable.

  3. Magnetization, magnetic susceptibility, effective magnetic moment of Fe{sup 3+} ions in Bi{sub 25}FeO{sub 39} ferrite

    SciTech Connect (OSTI)

    Zatsiupa, A.A., E-mail: zatsiupa@mail.ru [Belarussian State Technological University, 220030 Minsk (Belarus); Bashkirov, L.A. [Belarussian State Technological University, 220030 Minsk (Belarus); Troyanchuk, I.O. [Scientific and Practical Materials Research Centre of the NAS of Belarus, 220072 Minsk (Belarus); Petrov, G.S. [Belarussian State Technological University, 220030 Minsk (Belarus); Galyas, A.I.; Lobanovsky, L.S.; Truhanov, S.V. [Scientific and Practical Materials Research Centre of the NAS of Belarus, 220072 Minsk (Belarus)

    2014-04-01T23:59:59.000Z

    Magnetic susceptibility for ferrite Bi{sub 25}FeO{sub 39} is measured at 5–950 K in the magnetic field of 0.86 T. It is shown that Bi{sub 25}FeO{sub 39} is paramagnetic in the temperature range 5?950 K. The saturation magnetization is equal to 5.04?{sub B} per formula unit at 5 K in a magnetic field of 10 T. It is found that at 5?300 K the effective magnetic moment of Fe{sup 3+} ions in Bi{sub 25}FeO{sub 39} is equal to 5.82?{sub B}. - Graphical abstract: The dependence of the magnetization (n, ?{sub B}) on the magnetic field for one formula unit of Bi{sub 25}FeO{sub 39} at 5 K. - Highlights: • Magnetic susceptibility for Bi{sub 25}FeO{sub 39} is measured at 5–950 K in the magnetic field of 0.86 T. • It is shown that Bi{sub 25}FeO{sub 39} is paramagnetic in the temperature range 5?950 K. • The saturation magnetization is equal to 5.04?{sub B} per formula unit at 5 K in a magnetic field of 10 T.

  4. Electron density and electron temperature measurement in a bi-Maxwellian electron distribution using a derivative method of Langmuir probes

    SciTech Connect (OSTI)

    Choi, Ikjin; Chung, ChinWook [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)] [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Youn Moon, Se [High-Enthalpy Plasma Research Center, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabuk-do 561-756 (Korea, Republic of)] [High-Enthalpy Plasma Research Center, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabuk-do 561-756 (Korea, Republic of)

    2013-08-15T23:59:59.000Z

    In plasma diagnostics with a single Langmuir probe, the electron temperature T{sub e} is usually obtained from the slope of the logarithm of the electron current or from the electron energy probability functions of current (I)-voltage (V) curve. Recently, Chen [F. F. Chen, Phys. Plasmas 8, 3029 (2001)] suggested a derivative analysis method to obtain T{sub e} by the ratio between the probe current and the derivative of the probe current at a plasma potential where the ion current becomes zero. Based on this method, electron temperatures and electron densities were measured and compared with those from the electron energy distribution function (EEDF) measurement in Maxwellian and bi-Maxwellian electron distribution conditions. In a bi-Maxwellian electron distribution, we found the electron temperature T{sub e} obtained from the method is always lower than the effective temperatures T{sub eff} derived from EEDFs. The theoretical analysis for this is presented.

  5. Mössbauer investigations of hyperfine interactions features of {sup 57}Fe nuclei in BiFeO{sub 3} ferrite

    SciTech Connect (OSTI)

    Sobolev, Alexey, E-mail: salex12@rambler.ru; Presniakov, Igor, E-mail: salex12@rambler.ru; Rusakov, Vyacheslav, E-mail: salex12@rambler.ru; Matsnev, Mikhail; Gorchakov, Dmitry; Glazkova, Iana [Lomonosov Moscow State University, 119991, Moscow (Russian Federation); Belik, Alexey [International Center for Materials Nanoarchitectonics (MANA), National Institute for Material Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki, 305-0044 (Japan)

    2014-10-27T23:59:59.000Z

    New results of {sup 57}Fe Mössbauer studies on BiFeO{sub 3} powder sample performed at various temperatures above and below magnetic phase transitions point T{sub N} ? 640K are reported. We have performed self-consistent calculations of the lattice contributions to the EFG tensor, taking into account dipole moments of the O{sup 2?} and Bi{sup 3+} ions. Low-temperature {sup 57}Fe Mössbauer spectra recorded at T < T{sub N} were analyzed assuming an anharmonic cycloidal modulation of the Fe{sup 3+} magnetic moments. The cycloidal modulation of the iron spin was described with the elliptic Jacobi function sn[(±4K(m)/?)x,m]. The good fit of the experimental spectra was obtained for the anharmonicity m = 0.44 ± 0.04 (T = 4.9K) resulting from the easy-axis magnetic anisotropy.

  6. Strain effects on in-plane conductance of the topological insulator Bi{sub 2}Te{sub 3}

    SciTech Connect (OSTI)

    Heui Hwang, Jin; Kwon, Sangku; Hun Kim, Jong; Young Park, Jeong, E-mail: jeongypark@kaist.ac.kr [Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 305-701 (Korea, Republic of); Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701 (Korea, Republic of); Park, Joonbum; Sung Kim, Jun [Department of Physics, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Lee, Jhinhwan [Department of Physics, KAIST, Daejeon 305-701 (Korea, Republic of); Lyeo, Ho-Ki [Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 305-340 (Korea, Republic of)

    2014-04-21T23:59:59.000Z

    We investigated the correlation between electrical transport and mechanical stress in a topological insulator, Bi{sub 2}Te{sub 3}, using conductive probe atomic force microscopy in an ultrahigh vacuum environment. After directly measuring charge transport on the cleaved Bi{sub 2}Te{sub 3} surface, we found that the current density varied with applied load. Current mapping revealed a variation of the current on different terraces. The current density increased in the low-pressure regime and then decreased in the high-pressure regime. This variation of current density was explained in light of the combined effect of changes in the in-plane conductance due to spin–orbit coupling and hexagonal warping.

  7. Duality and integrability: Electromagnetism, linearized gravity, and massless higher spin gauge fields as bi-Hamiltonian systems

    SciTech Connect (OSTI)

    Barnich, Glenn; Troessaert, Cedric [Physique Theorique et Mathematique, Universite Libre de Bruxelles and International Solvay Institutes, Campus Plaine C.P. 231, B-1050 Bruxelles (Belgium)

    2009-04-15T23:59:59.000Z

    In the reduced phase space of electromagnetism, the generator of duality rotations in the usual Poisson bracket is shown to generate Maxwell's equations in a second, much simpler Poisson bracket. This gives rise to a hierarchy of bi-Hamiltonian evolution equations in the standard way. The result can be extended to linearized Yang-Mills theory, linearized gravity, and massless higher spin gauge fields.

  8. 2M : un Espace de Conception pour l'Interaction Bi-Manuelle Gilles Bailly, Laurence Nigay

    E-Print Network [OSTI]

    Bailly, Gilles

    2M : un Espace de Conception pour l'Interaction Bi-Manuelle Gilles Bailly, Laurence Nigay Lab @ # 9G: @ 2 # 0 2 # 0 # # 1 0 H ;.-!4. I8 ! >A J > II8 * ? " # II8 +"! K KKKKK KKK KHKKHKKKK L8 II #12 ? # > # & 3 2 ' ## & 3 ' ! !( ( V # V V V 9AA: 3 3 ( # ! !( W 9X: # # W W # F & ' 1 # 9X: 3 · * 7 3 C

  9. Anisotropic scattering rate in Fe-substituted Bi 2 Sr 2 Ca ( Cu 1 - x Fe x ) 2 O 8 + ?

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

    Naamneh, M.; Lubashevsky, Y.; Lahoud, E.; Gu, G. D.; Kanigel, A.

    2015-05-01T23:59:59.000Z

    We measured the electronic structure of Fe-substituted Bi2212 using angle-resolved photoemission spectroscopy. We find that the substitution does not change the momentum dependence of the superconducting gap but induces a very anisotropic enhancement of the scattering rate. A comparison of the effect of Fe substitution to that of Zn substitution suggests that the Fe reduces Tc so effectively because it suppresses very strongly the coherence weight around the antinodes.

  10. EPR investigation of defects in Bi12GeO20:Cr single crystal irradiated by high energy uranium ions

    E-Print Network [OSTI]

    Stefaniuk, I; Rogalska, I; Wróbel, D

    2013-01-01T23:59:59.000Z

    The results of investigations of EPR spectra of chromium doped $Bi_{12} GeO_{20} (BGO)$ single crystals are presented. The crystals were studied before and after irradiation by the $^{235}U$ ions with energy 9.47 MeV/u and fluency $5 \\cdot 10^{2} cm^{-2}$. The effect of heating irradiated samples in air on the EPR spectra is also studied.

  11. Piezoelectricity and local structural distortions in (Na{sub 0.5}Bi{sub 0.5}){sub 1-x}Sr{sub x}TiO{sub 3}-Bi{sub 12}TiO{sub 20} flexoelectric-type polar ceramics

    SciTech Connect (OSTI)

    Wang, L. H.; Zhao, M. L.; Wang, C. L.; Wang, J.; Kuai, W. J.; Tao, X. T. [School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100 (China)

    2012-08-06T23:59:59.000Z

    We have previously described sintered Na{sub 0.5}Bi{sub 0.5}TiO{sub 3}-Bi{sub 12}TiO{sub 20} composites as flexoelectric-type polar ceramics because they have a net macroscopic flexoelectric polarization. Here, we report on the universal existence of the macroscopic flexoelectric polarization in the (Na{sub 0.5}Bi{sub 0.5}){sub 1-x}Sr{sub x}TiO{sub 3}-Bi{sub 12}TiO{sub 20} system, in which enhanced piezoelectricity is observed. By combining Raman spectroscopy and x-ray photoelectron spectroscopy techniques, we have identified the local flexoelectric polarization as distorted BiO{sub 5} polyhedra and TiO{sub 6} octahedra in the SrTiO{sub 3}-Bi{sub 12}TiO{sub 20} ceramic. The macroscopic polarization may be due to the partial alignment of these distorted units located within the grain boundary amorphous phases. Bi{sub 12}TiO{sub 20} could have an important role in these flexoelectric-type polar ceramics.

  12. Manufacturing of High-Efficiency Bi-Facial Tandem Concentrator Solar Cells: February 20, 2009--August 20, 2010

    SciTech Connect (OSTI)

    Wojtczuk , S.

    2011-06-01T23:59:59.000Z

    Spire Semiconductor made concentrator photovoltaic (CPV) cells using a new bi-facial growth process and met both main program goals: a) 42.5% efficiency 500X (AM1.5D, 25C, 100mW/cm2); and b) Ready to supply at least 3MW/year of such cells at end of program. We explored a unique simple fabrication process to make a N/P 3-junction InGaP/GaAs/InGaAs tandem cells . First, the InGaAs bottom cell is grown on the back of a GaAs wafer. The wafers are then loaded into a cassette, spin-rinsed to remove particles, dipped in dilute NH4OH and spin-dried. The wafers are then removed from the cassette loaded the reactor for GaAs middle and InGaP top cell growth on the opposite wafer face (bi-facial growth). By making the epitaxial growth process a bit more complex, we are able to avoid more complex processing (such as large area wafer bonding or epitaxial liftoff) used in the inverted metamorphic (IMM) approach to make similar tandem stacks. We believe the yield is improved compared to an IMM process. After bi-facial epigrowth, standard III-V cell steps (back metal, photolithography for front grid, cap etch, AR coat, dice) are used in the remainder of the process.

  13. Toward understanding the formation of multiple systems - A pilot IRAM-PdBI survey of Class 0 objects

    E-Print Network [OSTI]

    Maury, A J; Hennebelle, P; Motte, F; Stamatellos, D; Bate, M; Belloche, A; Duchene, G; Whitworth, A

    2010-01-01T23:59:59.000Z

    The formation process of binary stars and multiple systems is poorly understood. Here, we seek to determine the typical outcome of protostellar collapse and to constrain models of binary formation by core fragmentation during collapse, using high-resolution millimeter continuum imaging of very young (Class 0) protostars observed at the beginning of the main accretion phase. We carried out a pilot high-resolution study of 5 Class 0 objects, using the most extended (A) configuration of the IRAM PdBI at 1.3 mm, which allow us to probe the multiplicity of Class 0 protostars down to separations a ~50 AU and circumstellar mass ratios q ~0.07. We show that our PdBI observations revealed only wide (>1500 AU) protobinary systems and/or outflow-generated features. When combined with previous millimeter interferometric observations of Class 0 protostars, our pilot PdBI study tentatively suggests that the binary fraction in the ~ 75-1000 AU range increases from the Class 0 to the Class I stage. It also seems to argue aga...

  14. Ab initio investigation of the exchange interactions in Bi$_2$Fe$_4$O$_9$: The Cairo pentagonal lattice compound

    E-Print Network [OSTI]

    Z. V. Pchelkina; S. V. Streltsov

    2013-08-05T23:59:59.000Z

    We present the \\emph{ab initio} calculation of the electronic structure and magnetic properties of Bi$_2$Fe$_4$O$_9$. This compound crystallizes in the orthorhombic crystal structure with the Fe$^{3+}$ ions forming the Cairo pentagonal lattice implying strong geometric frustration. The neutron diffraction measurements reveal nearly orthogonal magnetic configuration, which at first sight is rather unexpected since it does not minimize the total energy of the pair of magnetic ions coupled by the Heisenberg exchange interaction. Here we calculate the electronic structure and exchange integrals of Bi2Fe4O9 within the LSDA+U method. We obtain three different in-plane (J3=36 K, J4=73 K, J5=23 K) and two interplane (J1=10 K, J2=12 K) exchange parameters. The derived set of exchange integrals shows that the realistic description of Bi2Fe4O9 needs a more complicated model than the ideal Cairo pentagonal lattice with only two exchange parameters in the plane. However, if one takes into account only two largest exchange integrals, then according to the ratio x\\equiv J3/J4=0.49<\\sqrt{2} (a critical parameter for the ideal Cairo pentagonal lattice, see. Ref.~1) the ground state should be the orthogonal magnetic configuration in agreement with experiment. The microscopic origin of different exchange interactions is also discussed.

  15. Improved leakage current and ferromagnetic properties in magnetic field annealed BiFeO{sub 3}-based ceramics

    SciTech Connect (OSTI)

    Yin, L.H.; Zhao, B.C. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China)] [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Fang, J.; Zhang, R.R. [High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China)] [High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China); Tang, X.W. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China)] [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Song, W.H., E-mail: whsong@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Dai, J.M. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China)] [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Sun, Y.P., E-mail: ypsun@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China)

    2012-10-15T23:59:59.000Z

    Single-phase Bi{sub 0.85}La{sub 0.15}FeO{sub 3} ceramics were synthesized under various magnetic fields (H{sub a}=0 T, 3 T, 5 T). Substantially reduced leakage current and hence modified ferroelectric (FE) properties were obtained with magnetic field annealing (MA). The largest magnetization and lowest leakage current with large FE polarization (P{sub r}{approx}33 {mu}C/cm{sup 2}) were found in the sample annealed with H{sub a}=3 T. Great changes were also observed in the Raman spectra. All the observed features originate mainly from the different FE domain wall structures induced by MA. These results demonstrate that MA is an effective way to tune the multiferroic and magnetoelectric properties in BiFeO{sub 3}-based materials. - Graphical abstract: Bright field TEM micrograph of the representative domain structures in the samples (a) BLF0, (b) BLF3 and (c) BLF5. Highlights: Black-Right-Pointing-Pointer Bi{sub 0.85}La{sub 0.15}FeO{sub 3} ceramics were synthesized under various magnetic fields. Black-Right-Pointing-Pointer Substantially reduced leakage current with improved ferroelectricity were obtained. Black-Right-Pointing-Pointer Enhanced magnetization with moderate annealing magnetic field.

  16. Performance of Titanium-Oxide/Polymer Insulation in Bi-2212/Ag-alloy Round Wire Wound Superconducting Coils

    E-Print Network [OSTI]

    Chen, Peng; Dalban-Canassy, Matthieu; Jiang, Jianyi; Hellstrom, Eric E; Larbalestier, David C

    2013-01-01T23:59:59.000Z

    Conductor insulation is one of the key components needed to make Ag-alloy clad Bi2Sr2CaCu2O8+x (Bi-2212/Ag) superconducting round wire (RW) successful for high field magnet applications as dielectric standoff and high winding current densities (Jw) directly depend on it. In this study, a TiO2/polymer insulation coating developed by nGimat LLC was applied to test samples and a high field test coil. The insulation was investigated by differential thermal analysis (DTA), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), dielectric properties measurement, and transport critical current (Ic) properties measurement. About 29% of the insulation by weight is polymer. When the Bi-2212/Ag wire is full heat treated, this decomposes with slow heating to 400{\\deg}C in pure O2. After the full reaction, we found that the TiO2 did not degrade the critical current properties, adhered well to the conductor, and provided a breakdown voltage of >100 V, which allowed the test coil to survive quenching in 31.2...

  17. Fe3O4-LiMo3Se3 Nanoparticle Clusters as Superparamagnetic Nanocompasses

    E-Print Network [OSTI]

    Osterloh, Frank

    -iodopropionic acid treated LiMo3Se3 nanowire bundles with oleic acid-stabilized Fe3O4 nanoparticles of 2.8, 5Fe3O4-LiMo3Se3 Nanoparticle Clusters as Superparamagnetic Nanocompasses Frank E. Osterloh,*, Hiroki A scaleable chemical approach to functional nanoscale analogues of the magnetic compasses in magnetotactic

  18. Photovoltaic cells fabricated by electrophoretic deposition of CdSe nanocrystals

    E-Print Network [OSTI]

    Smith, Nathanael J.

    Photovoltaic cells fabricated by electrophoretic deposition of CdSe nanocrystals Nathanael J. Smith Electrophoretic deposition was used to deposit CdSe nanocrystals on TiO2 for use in photovoltaic cells formed. A solar cell constructed using electrophoretic deposition exhibited a photovoltaic response from

  19. Testing models for the Messinian salinity crisis: The Messinian record in Almera, SE Spain

    E-Print Network [OSTI]

    Riding, Robert

    Testing models for the Messinian salinity crisis: The Messinian record in AlmerĂ­a, SE Spain Juan C Fuentenueva s.n., Universidad de Granada, 18002 Granada, Spain b School of Earth, Ocean and Planetary Sciences, SE Spain, display excellent exposures of Messinian (Late Miocene) sequences. The Sorbas, AlmerĂ­a

  20. Rapid degradation of CdSe/ZnS colloidal quantum dots exposed to gamma irradiation

    E-Print Network [OSTI]

    New Mexico, University of

    Rapid degradation of CdSe/ZnS colloidal quantum dots exposed to gamma irradiation Nathan J. Withers are reported. Optical degradation is evaluated by tracking the dependence of photoluminescence intensity on irradiation dose. CdSe/ZnS quantum dots show poor radiation hardness, and severely degrade after less than 20

  1. Development of a Low Cost Insulated Foil Substrate for Cu(InGaSe)2 Photovoltaics

    SciTech Connect (OSTI)

    ERTEN ESER

    2012-01-22T23:59:59.000Z

    The project validated the use of stainless steel flexible substrate coated with silicone-based resin dielectric, developed by Dow Corning Corporation, for Cu(InGa)Se2 based photovoltaics. The projects driving force was the high performance of Cu(InGa)Se2 based photovoltaics coupled with potential cost reduction that could be achieved with dielectric coated SS web substrate.

  2. Thermoelectric Properties of p-Type PbSe Nanowires Wenjie Liang1,3

    E-Print Network [OSTI]

    Yang, Peidong

    Thermoelectric Properties of p-Type PbSe Nanowires Wenjie Liang1,3 , Oded Rabin1,4 , Allon I-009-9039-2 Research Article Address correspondence to p_yang@berkeley.edu ABSTRACT The thermoelectric properties to 300 K. Thermal annealing of the PbSe nanowires allowed their thermoelectric properties

  3. CdSe Nanocrystals using the Oleic Acid Synthesis Nathanael J. Smith, Fall 2008

    E-Print Network [OSTI]

    Smith, Nathanael J.

    #12;4 M Se in TPB Take 15 g of Se powder in an appropriately sized glass bottle (it must hold at least the lid on the bottle to stop the TBP from evaporating). Perodically give the contents of the bottle

  4. Charge transport in mixed CdSe and CdTe colloidal nanocrystal films

    E-Print Network [OSTI]

    Bawendi, Moungi G.

    We report the influence of trap states on charge transport through films of mixed CdTe and CdSe nanocrystals (NCs) between lateral electrodes, through layered films of CdTe and CdSe NCs in a layered geometry, and through ...

  5. Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3

    E-Print Network [OSTI]

    Shen, Guoyin

    Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3 P. P. Kong1 , F. Sun1,3 , L. Y induce Sb2Se3 into a topological nontrivial state. Here, we report on the discovery of superconductivity superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition

  6. Alfvenic modes in a bi-Maxwellian electron-ion plasma

    SciTech Connect (OSTI)

    Bashir, M. F.; Iqbal, Z.; Aslam, I. [Salam Chair, Government College University Lahore, Punjab 54000 (Pakistan); Department of Physics, Government College University Lahore, Punjab 54000 (Pakistan); Murtaza, G. [Salam Chair, Government College University Lahore, Punjab 54000 (Pakistan)

    2010-10-15T23:59:59.000Z

    Employing linearized Vlasov-Maxwell system, we derive a generalized dielectric tensor for a magnetized nonrelativistic bi-Maxwellian electron-ion plasma. Assuming low frequency waves in a low {beta} plasma, a new dispersion relation describing oblique propagation of the Alfvenic modes is determined, incorporating the temperature anisotropies of both the electrons and ions and their finite Larmor radii effects. From the resulting dispersion relation for kinetic Alfven waves, analytical expressions are determined for both the kinetic (v{sub t||}){sub i}<<{omega}/k{sub ||}<>v{sub t||e,i} and {beta}<

  7. Crossing of large multiquasiparticle magnetic-rotation bands in $^{198}$Bi

    E-Print Network [OSTI]

    H. Pai; G. Mukherjee; S. Bhattacharyya; C. Bhattacharya; S. Bhattacharya; T. Bhattacharjee; S. K. Basu; S. Kundu; T. K. Ghosh; K. Banerjee; T. K. Rana; J. K. Meena; R. K. Bhowmik; R. P. Singh; S. Muralithar; S. Chanda; R. Garg; B. Maheshwari; D. Choudhury; A. K. Jain

    2014-12-22T23:59:59.000Z

    High-spin states in the doubly-odd $^{198}$Bi nucleus have been studied by using the $^{185,187}$Re($^{16}$O, xn) reactions at the beam energy of 112.5 MeV. $\\gamma-\\gamma$ coincidence were measured by using the INGA array with 15 Compton suppressed clover HPGe detectors. The observed levels have been assigned definite spin-parity. The high spin structure is grouped into three bands (B1, B2 and B3), of which two (B1 and B2) exhibit the properties of magnetic rotation (MR). Tilted axis cranking calculations were carried out to explain the MR bands having large multi-quasiparticle configurations. The calculated results explain the bands B1 and B2 very nicely, confirming the shears mechanism and suggest a crossing of two MR bands in both the cases. The crossing is from 6-qp to 8-qp in band B1 and from 4-qp to 6-qp in band B2, a very rare finding. A semiclassical model has also been used to obtain the particle-hole interaction strengths for the bands B1 and B2, below the band crossing.

  8. Bi-conformal symmetry and static Green functions in the Schwarzschild-Tangherlini spacetimes

    E-Print Network [OSTI]

    Valeri P. Frolov; Andrei Zelnikov

    2014-12-21T23:59:59.000Z

    We study static massless minimally coupled scalar field created by a source in a static D-dimensional spacetime. We demonstrate that the corresponding equation for this field is invariant under a special transformation of the background metric. This transformation consists of the static conformal transformation of the spatial part of the metric accompanied by a properly chosen transformation of the red-shift factor. Both transformations are determined by one function of the spatial coordinates. We show that in a case of higher dimensional spherically symmetric black holes one can find such a bi-conformal transformation that the symmetry of the D-dimensional metric is enhanced after its application. Namely, the metric becomes a direct sum of the metric on a unit sphere and the metric of 2D anti-de Sitter space. The method of the heat kernels is used to find the Green function in this new space, that allows one, after dimensional reduction, to obtain a static Green function in the original space of the static black hole. The general useful representation of static Green functions is obtained in the Schwarzschild-Tangherlini spacetimes of arbitrary dimension. The exact explicit expressions for the static Green functions are obtained in such metrics for D Green function coincides with the Copson solution.

  9. Phase equilibria in the quasi-ternary system Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} and physical properties of (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} single crystals

    SciTech Connect (OSTI)

    Ivashchenko, I.A., E-mail: inna.ivashchenko@mail.ru [Department of Inorganic and Physical Chemistry, Eastern European National University, Voli Ave 13, Lutsk 43025 (Ukraine); Danyliuk, I.V.; Olekseyuk, I.D. [Department of Inorganic and Physical Chemistry, Eastern European National University, Voli Ave 13, Lutsk 43025 (Ukraine); Halyan, V.V. [Department of General Physics, Eastern European National University, Voli Ave 13, Lutsk 43025 (Ukraine)

    2014-02-15T23:59:59.000Z

    The quasi-ternary system Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} was investigated by differential thermal, X-ray phase, X-ray structure, microstructure analysis and microhardness measurements. Five quasi-binary phase diagrams, six polythermal sections, isothermal section at 820 K and the liquidus surface projection were constructed. The character and temperature of the invariant processes were determined. The specific resistance of the single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} was measured, 7.5×10{sup 5} and 3.15×10{sup 5} ? m, respectively, optical absorption spectra in the 600–1050 nm range were recorded at room temperature, and the band gap energy was estimated which is 1.95±0. 01 eV for both samples. - Graphical abstract: The article reports for the first time the investigated liquidus surface projection of the Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system and isothermal section at 820 K of the system. Five phase diagrams, six polythermal sections, isothermal section at 820 K and the liquidus surface projection were built at the first time. The existence of the large region of the solid solutions based on AgIn{sub 5}Se{sub 8}, Ga{sub 2}Se{sub 3} and AgGa{sub 1?x}In{sub x}Se{sub 2} was investigated. The existence of two ternary phases was established in the Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system. Two single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} were grown and some of optical properties of them were studied at first time. Display Omitted - Highlights: • Liquidus surface projection was built for Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system. • Solid solution ranges of AgIn{sub 5}Se{sub 8}, Ga{sub 2}Se{sub 3} and AgGa{sub 1?x}In{sub x}Se{sub 2} were investigated. • Two single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} were grown. • Some optical properties of these single crystals were studied.

  10. SE HAN FINALIZADO LOS PREPARATIVOS PARA LA CONFERENCIA NACIONAL DE JUSTICIA MEDIOAMBIENTAL Y PROGRAMA DE FORMACIÓN 2013

    Broader source: Energy.gov [DOE]

    La National Environmental Justice Conference, Inc. (Conferencia de Justicia Medioambiental) se prepara para otro exitoso acontecimiento, ya que se aproxima la Conferencia Nacional de Justicia...

  11. Breast Imaging Reporting and Data System (BI-RADS) breast composition descriptors: Automated measurement development for full field digital mammography

    SciTech Connect (OSTI)

    Fowler, E. E.; Sellers, T. A.; Lu, B. [Department of Cancer Epidemiology, Division of Population Sciences, H. Lee Moffitt Cancer Center, Tampa, Florida 33612 (United States)] [Department of Cancer Epidemiology, Division of Population Sciences, H. Lee Moffitt Cancer Center, Tampa, Florida 33612 (United States); Heine, J. J. [Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center, Tampa, Florida 33612 (United States)] [Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center, Tampa, Florida 33612 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: The Breast Imaging Reporting and Data System (BI-RADS) breast composition descriptors are used for standardized mammographic reporting and are assessed visually. This reporting is clinically relevant because breast composition can impact mammographic sensitivity and is a breast cancer risk factor. New techniques are presented and evaluated for generating automated BI-RADS breast composition descriptors using both raw and calibrated full field digital mammography (FFDM) image data.Methods: A matched case-control dataset with FFDM images was used to develop three automated measures for the BI-RADS breast composition descriptors. Histograms of each calibrated mammogram in the percent glandular (pg) representation were processed to create the new BR{sub pg} measure. Two previously validated measures of breast density derived from calibrated and raw mammograms were converted to the new BR{sub vc} and BR{sub vr} measures, respectively. These three measures were compared with the radiologist-reported BI-RADS compositions assessments from the patient records. The authors used two optimization strategies with differential evolution to create these measures: method-1 used breast cancer status; and method-2 matched the reported BI-RADS descriptors. Weighted kappa (?) analysis was used to assess the agreement between the new measures and the reported measures. Each measure's association with breast cancer was evaluated with odds ratios (ORs) adjusted for body mass index, breast area, and menopausal status. ORs were estimated as per unit increase with 95% confidence intervals.Results: The three BI-RADS measures generated by method-1 had ? between 0.25–0.34. These measures were significantly associated with breast cancer status in the adjusted models: (a) OR = 1.87 (1.34, 2.59) for BR{sub pg}; (b) OR = 1.93 (1.36, 2.74) for BR{sub vc}; and (c) OR = 1.37 (1.05, 1.80) for BR{sub vr}. The measures generated by method-2 had ? between 0.42–0.45. Two of these measures were significantly associated with breast cancer status in the adjusted models: (a) OR = 1.95 (1.24, 3.09) for BR{sub pg}; (b) OR = 1.42 (0.87, 2.32) for BR{sub vc}; and (c) OR = 2.13 (1.22, 3.72) for BR{sub vr}. The radiologist-reported measures from the patient records showed a similar association, OR = 1.49 (0.99, 2.24), although only borderline statistically significant.Conclusions: A general framework was developed and validated for converting calibrated mammograms and continuous measures of breast density to fully automated approximations for the BI-RADS breast composition descriptors. The techniques are general and suitable for a broad range of clinical and research applications.

  12. Diamond-machined ZnSe immersion grating for NIR high-resolution spectroscopy

    SciTech Connect (OSTI)

    Ikeda, Y; Kobayashi, N; Kuzmenko, P J; Little, S L; Yasui, C; Kondo, S; Minami, A; Motohara, K

    2008-07-25T23:59:59.000Z

    ZnSe immersion gratings (n {approx} 2.45) provide the possibility of high-resolution spectroscopy for the near-infrared (NIR) region. Since ZnSe has a lower internal attenuation than other NIR materials, it is most suitable for immersion grating, particularly in short NIR region (0.8-1.4 {micro}m). We are developing an extremely high-resolution spectrograph with {lambda}/{Delta}{lambda} = 100,000, WINERED, customized for the short NIR region, using ZnSe (or ZnS) immersion grating. However, it had been very difficult to make fine grooves on ZnSe substrate with a small pitch of less than 50 {micro}m because ZnSe is a soft/brittle material. We have overcome this problem and successfully machined sharp grooves with fine pitch on ZnSe substrates by nano precision fly-cutting technique at LLNL. The optical testing of the sample grating with HeNe laser shows an excellent performance: the relative efficiency more than 87.4 % at 0.633 {micro}m for a classical grating configuration. The diffraction efficiency when used as an immersion grating is estimated to be more than 65 % at 1 {micro}m. Following this progress, we are about to start machining a grating on a large ZnSe prism with an entrance aperture of 23mm x 50mm and the blaze angle of 70{sup o}.

  13. Hydrothermal synthesis, structure, and magnetic properties of Pu(SeO{sub 3}){sub 2}

    SciTech Connect (OSTI)

    Bray, Travis H. [Department of Chemistry and Biochemistry and Center for Actinide Science, Auburn University, Auburn, AL 36849 (United States); Skanthakumar, S.; Soderholm, L. [Chemistry Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Sykora, Richard E. [Department of Chemistry, University of South Alabama, Mobile, AL 36688 (United States); Haire, Richard G. [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Albrecht-Schmitt, Thomas E. [Department of Chemistry and Biochemistry and Center for Actinide Science, Auburn University, Auburn, AL 36849 (United States)], E-mail: albreth@auburn.edu

    2008-03-15T23:59:59.000Z

    The reaction between PuO{sub 2} and SeO{sub 2} under mild hydrothermal conditions results in the formation of Pu(SeO{sub 3}){sub 2} as brick-red prisms. This compound adopts the Ce(SeO{sub 3}){sub 2} structure type, and consists of one-dimensional chains of edge-sharing [PuO{sub 8}] distorted bicapped trigonal prisms linked by [SeO{sub 3}] units into a three-dimensional network. Crystallographic data: Pu(SeO{sub 3}){sub 2}, monoclinic, space group P2{sub 1}/n, a=6.960(1) A, b=10.547(2) A, c=7.245(1) A, {beta}=106.880(9){sup o}, V=508.98(17) A{sup 3}, Z=4 (T=193 K), R(F)=2.92% for 83 parameters with 1140 reflections with I>2{sigma}(I). Magnetic susceptibility data for Pu(SeO{sub 3}){sub 2} are linear from 35 to 320 K and yield an effective moment of 2.71(5) {mu}{sub B} and a Weiss constant of -500(5) K. - Graphical abstract: A depiction of the three-dimensional structure of Pu(SeO{sub 3}){sub 2} formed from the interconnection of one-dimensional chains of edge-sharing PuO{sub 8} dodecahedra by selenite anions.

  14. INCOSE Systems Engineering Handbook v3.2: Improving the Process for SE Practitioners

    SciTech Connect (OSTI)

    R. Douglas Hamelin; David D. Walden; Michael E. Krueger

    2010-07-01T23:59:59.000Z

    The INCOSE Systems Engineering Handbook is the official INCOSE reference document for understanding systems engineering (SE) methods and conducting SE activities. Over the years, the Handbook has evolved to accommodate advances in the SE discipline and now serves as the basis for the Certified Systems Engineering Professional (CSEP) exam. Due to its evolution, the Handbook had become somewhat disjointed in its treatment and presentation of SE topics and was not aligned with the latest version of International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC) 15288:2008, Systems and Software Engineering. As a result, numerous inconsistencies were identified that could confuse practitioners and directly impact the probability of success in passing the CSEP exam. Further, INCOSE leadership had previously submitted v3.1 of the Handbook to ISO/IEC for consideration as a Technical Report, but was told that the Handbook would have to be updated to conform with the terminology and structure of new ISO/IEC15288:2008, Systems and software engineering, prior to being considered. The revised INCOSE Systems Engineering Handbook v3.2 aligns with the structure and principles of ISO/IEC 15288:2008 and presents the generic SE life-cycle process steps in their entirety, without duplication or redundancy, in a single location within the text. As such, the revised Handbook v3.2 serves as a comprehensive instructional and reference manual for effectively understanding SE processes and conducting SE and better serves certification candidates preparing for the CSEP exam.

  15. Structure and magnetic properties of low-temperature phase Mn-Bi nanosheets with ultra-high coercivity and significant anisotropy

    SciTech Connect (OSTI)

    Liu, Rongming, E-mail: rmliu@iphy.ac.cn, E-mail: shenbg@iphy.ac.cn; Zhang, Ming; Niu, E; Li, Zhubai; Zheng, Xinqi; Wu, Rongrong; Zuo, Wenliang; Shen, Baogen; Hu, Fengxia; Sun, Jirong [State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-05-07T23:59:59.000Z

    The microstructure, crystal structure, and magnetic properties of low-temperature phase (LTP) Mn-Bi nanosheets, prepared by surfactant assistant high-energy ball milling (SA-HEBM) with oleylamine and oleic acid as the surfactant, were examined with scanning electron microscopy, X-ray diffraction, and vibrating sample magnetometer, respectively. Effect of ball-milling time on the coercivity of LTP Mn-Bi nanosheets was systematically investigated. Results show that the high energy ball milling time from tens of minutes to several hours results in the coercivity increase of Mn-Bi powders and peak values of 14.3 kOe around 10 h. LTP Mn-Bi nanosheets are characterized by an average thickness of tens of nanometers, an average diameter of ?1.5??m, and possess a relatively large aspect ratio, an ultra-high room temperature coercivity of 22.3 kOe, a significant geometrical and magnetic anisotropy, and a strong (00l) crystal texture. Magnetization and demagnetization behaviors reveal that wall pinning is the dominant coercivity mechanism in these LTP Mn-Bi nanosheets. The ultrafine grain refinement introduced by the SA-HEBM process contribute to the ultra-high coercivity of LTP Mn-Bi nanosheets and a large number of defects put a powerful pinning effect on the magnetic domain movement, simultaneously. Further magnetic measurement at 437?K shows that a high coercivity of 17.8 kOe and a strong positive temperature coefficient of coercivity existed in the bonded permanent magnet made by LTP Mn-Bi nanosheets.

  16. Hydrothermal synthesis and thermoelectric properties of nanostructured Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} compounds

    SciTech Connect (OSTI)

    Zhang, Yanhua [Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China) [Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China); Academy of Equipment Command and Technology, Beijing 102249 (China); Xu, Guiying [Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China)] [Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China); Mi, Jianli [Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, DK-8000 Aarhus (Denmark)] [Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, DK-8000 Aarhus (Denmark); Han, Fei; Wang, Ze [Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China)] [Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China); Ge, Changchun, E-mail: ccge@mater.ustb.edu.cn [Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China)] [Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China)

    2011-05-15T23:59:59.000Z

    Research highlights: {yields} Single-phase Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} powders have been synthesized by a hydrothermal route. {yields} Hexagonal Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} naosheets due to the anisotropic growth of the crystals. {yields} The temperature gradients lead to directional arrangement nanosheet-agglomerates. {yields} Nanosheet-agglomerates are beneficial for improving the TE property of products. {yields} A maximum figure of merit of 0.86 is achieved at about 100 {sup o}C. -- Abstract: Single-phase Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} compounds have been prepared by hydrothermal synthesis at 150 {sup o}C for 24 h using SbCl{sub 3}, BiCl{sub 3} and tellurium powder as precursors. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) have been applied to analyze the phase distributions, microstructures and grain sizes of the as-grown Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} products. It is found that the hydrothermally synthesized Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} nanopowders have a morphology dominated by irregular hexagonal sheets due to the anisotropic growth of the crystals. The Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} nanosheets are parallelly stacked in certain direction to form sheet-agglomerates attribute to the temperature gradients in the solution.

  17. Characterization of ZnSe scintillating bolometers for Double Beta Decay

    E-Print Network [OSTI]

    C. Arnaboldi; S. Capelli; O. Cremonesi; L. Gironi; M. Pavan; G. Pessina; S. Pirro

    2010-06-30T23:59:59.000Z

    ZnSe scintillating bolometers are good candidates for future Double Beta Decay searches, because of the 82Se high Q-value and thanks to the possibility of alpha background rejection on the basis of the scintillation signal. In this paper we report the characteristics and the anomalies observed in an extensive study of these devices. Among them, an unexpected high emission from alpha particles, accompanied with an unusual pattern of the light vs. heat scatter plot. The perspectives for the application of this kind of detectors to search for the Neutrinoless Double Beta Decay of 82Se are presented.

  18. Optimal packing size of non-ligated CdSe nanoclusters for microstructure synthesis

    SciTech Connect (OSTI)

    Tefera, Anteneh G.; Mochena, Mogus D. [Department of Physics, Florida A and M University, Tallahassee, Florida 32307 (United States); Johnson, Elijah [School of Environment, Florida A and M University, Tallahassee, Florida 32307 (United States); Dickerson, James [Department of Physics, Brown University, Providence, Rhode Island 02912 (United States)

    2014-09-14T23:59:59.000Z

    Structural and electrostatic properties of nanoclusters of CdSe of diameter 1–2?nm are studied with first principle calculations to determine the optimal size for synthesizing microstructures. Based on robustness of the core structure, i.e., the retention of tetrahedral geometry, hexagonal ring structure, and overall wu{sup ¨}rtzite structure to surface relaxations, we conclude that nanoclusters of ?2?nm diameter are the best candidates to form a dense microstructure with minimal interstitial space. Se-terminated surfaces retain a zigzag structure as Se atoms are pulled out and Cd atoms are pulled in due to relaxation, therefore, are best suited for inter-nanocluster formations.

  19. Hidden Superlattice in Tl2(SC6H4S) and Tl2(SeC6H4Se) Solved from Powder X-ray Diffraction

    SciTech Connect (OSTI)

    K Stone; D Turner; M Singh; T Vaid; P Stephens

    2011-12-31T23:59:59.000Z

    The crystal structures of the isostructural title compounds poly[({mu}-benzene-1,4-dithiolato)dithallium], Tl{sub 2}(SC{sub 6}H{sub 4}S), and poly[({mu}-benzene-1,4-diselenolato)dithallium], Tl{sub 2}(SeC{sub 6}H{sub 4}Se), were solved by simulated annealing from high-resolution synchrotron X-ray powder diffraction. Rietveld refinements of an initial structure with one formula unit per triclinic cell gave satisfactory agreement with the data, but led to a structure with impossibly close non-bonded contacts. A disordered model was proposed to alleviate this problem, but an alternative supercell structure leads to slightly improved agreement with the data. The isostructural superlattice structures were confirmed for both compounds through additional data collection, with substantially better counting statistics, which revealed the presence of very weak superlattice peaks not previously seen. Overall, each structure contains Tl-S or Tl-Se two-dimensional networks, connected by phenylene bridges. The sulfur (or selenium) coordination sphere around each thallium is a highly distorted square pyramid or a 'see-saw' shape, depending upon how many Tl-S or Tl-Se interactions are considered to be bonds. In addition, the two compounds contain pairs of Tl{sup I} ions that interact through a closed-shell 'thallophilic' interaction: in the sulfur compound there are two inequivalent pairs of Tl atoms with Tl-Tl distances of 3.49 and 3.58 {angstrom}, while in the selenium compound those Tl-Tl interactions are at 3.54 and 3.63 {angstrom}.

  20. Enhanced Thermoelectric Power and Electronic Correlations in RuSe2

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

    Wang, Kefeng [Brookhaven National Laboratory (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.; Wang, Aifeng [Brookhaven National Laboratory (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.; Tomic, A. [Brookhaven National Laboratory (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.; Wang, Limin [Brookhaven National Laboratory (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.; Abeykoon, A.M. Milinda [Brookhaven National Laboratory (BNL), Upton, NY (United States). Photon Sciences Directorate; Dooryhee, E. [Brookhaven National Laboratory (BNL), Upton, NY (United States). Photon Sciences Directorate; Billinge, S. J.L. [Brookhaven National Laboratory (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.; Columbia Univ., New York, NY (United States); Petrovic, C. [Brookhaven National Laboratory (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.

    2015-04-01T23:59:59.000Z

    We report the electronic structure, electric and thermal transport properties of Ru1-xIrxSe2 (x ? 0:2). RuSe2 is a semiconductor that crystallizes in a cubic pyrite unit cell. The Seebeck coefficient of RuSe2 exceeds -200 ?#22;V/K around 730 K. Ir substitution results in the suppression of the resistivity and the Seebeck coefficient, suggesting the removal of the peaks in density of states near the Fermi level. Ru0.8Ir0.2Se2 shows a semiconductor-metal crossover at about 30 K. The magnetic field restores the semiconducting behavior. Our results indicate the importance of the electronic correlations in enhanced thermoelectricity of RuSb2.

  1. Evidence for Gassy Sediments on the Inner Shelf of SE Korea From Geoacoustic Properties

    E-Print Network [OSTI]

    , Gwang H. Lee 6 , Young K. Seo 5 1 * Hawaii Natural Energy Institute, University of Hawaii, P.O.S.T. Bldg Properties; Attenuation; Biodegradation; Bubbles; Core Analysis; Gassy Sediments; SE Korea Shelf #12

  2. UNIDAD GUADALAJARA La Unidad Guadalajara del Cinvestav se inici el 14 de noviembre de 1988 con

    E-Print Network [OSTI]

    ańos de distancia, la Unidad Guadalajara se ha convertido en uno de los grupos de ingeniería eléctrica, Canadá, y Japón. La Unidad Guadalajara del Cinvestav tiene cinco grupos de trabajo que desa- rrollan

  3. UNIDAD GUADALAJARA La Unidad Guadalajara del Cinvestav se inici el 14 de noviembre de 1988 con

    E-Print Network [OSTI]

    ańos de distancia, la Unidad Guadalajara se ha convertido en uno de los grupos de ingeniería eléctrica Estados Unidos, Canadá, y Japón. La Unidad Guadalajara del Cinvestav tiene cinco grupos de trabajo que

  4. WEATHERIZATION INDUSTRIES SAVE ENERGY ST SE SALEM, OREGON 97301 (503) 5691381 WEATHERIZATIONALLIES@GMAIL.COM

    E-Print Network [OSTI]

    WEATHERIZATION INDUSTRIES SAVE ENERGY 565 21ST ST SE SALEM, OREGON 97301 · (503) 5691381 · WEATHERIZATIONALLIES@GMAIL.COM COMMENTS ON ACHIEVABLE SAVINGS: A RETROSPECTIVE LOOK AT THE NORTHWEST POWER AND CONSERVATION COUNCIL'S CONSERVATION PLANNING ASSUMPTIONS Weatherization Industries Save Energy (WISE

  5. Structure, Magnetism, and Transport of CuCr2Se4 Thin Films

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    Structure, Magnetism, and Transport of CuCr 2 Se 4 Thindichroism shows that the magnetism persists to the surfacesuch as the nature of magnetism at surfaces and interfaces.

  6. Phonon properties of BaFe?X? (X=S, Se) spin ladder compounds

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

    Popovicq, Z. V.; Petrovic, C.; Scepanovic, M.; Lazarevic, N.; Opacic, M.; Radonjic, M. M.; Tanaskovic, D.; Lei, Hechang

    2015-02-01T23:59:59.000Z

    We present the Raman scattering spectra of the S=2 spin ladder compounds BaFe?X? (X=S,Se) in a temperature range between 20 and 400 K. Although the crystal structures of these two compounds are both orthorhombic and very similar, they are not isostructural. The unit cell of BaFe?S? (BaFe?Se?) is base-centered Cmcm (primitive Pnma), giving 18 (36) modes to be observed in the Raman scattering experiment. We have detected almost all Raman active modes, predicted by factor group analysis, which can be observed from the cleavage planes of these compounds. Assignment of the observed Raman modes of BaFe?S(Se)? is supported by themore »lattice dynamics calculations. The antiferromagnetic long-range spin ordering in BaFe?Se? below TN=255K leaves a fingerprint both in the A1g and B3g phonon mode linewidth and energy.« less

  7. Time resolved fluorescence of CdSe nanocrystals using single molecule spectroscopy

    E-Print Network [OSTI]

    Fisher, Brent R

    2005-01-01T23:59:59.000Z

    A wide variety of spectroscopic studies of CdSe nanocrystals (NCs) are presented in this thesis, all studying some aspect of the temporal evolution of NC fluorescence tinder different conditions. In particular the methods ...

  8. Nanofabrication, Plasmon Enhanced Fluorescence and Photo-oxidation Kinetics of CdSe Nanoparticles

    E-Print Network [OSTI]

    Chen, Jixin

    2011-08-08T23:59:59.000Z

    nanosphere (left) and nanoprism (right) solutions and (B) their corresponding absorption spectra displayed in yellow and green line, respectively. (C) TEM image of photoinduced Ag nanoprisms. The inserts show the electron diffraction analysis... this synthetic method, typical commercial CdSe nanocrystals have a size deviation less than 10% and narrow emission spectra with peak widths at half height of around 30- 50 nm for small ones that have 4 nm in diameter. The color changes of the CdSe quantum...

  9. Unique Challenges Accompany Thick-Shell CdSe/nCdS (n > 10) Nanocrystal Synthesis

    SciTech Connect (OSTI)

    Guo, Y; Marchuk, K; Abraham, R; Sampat, S; Abraham, R.; Fang, N; Malko, AV; Vela, J

    2011-12-23T23:59:59.000Z

    Thick-shell CdSe/nCdS (n {ge} 10) nanocrystals were recently reported that show remarkably suppressed fluorescence intermittency or 'blinking' at the single-particle level as well as slow rates of Auger decay. Unfortunately, whereas CdSe/nCdS nanocrystal synthesis is well-developed up to n {le} 6 CdS monolayers (MLs), reproducible syntheses for n {ge} 10 MLs are less understood. Known procedures sometimes result in homogeneous CdS nucleation instead of heterogeneous, epitaxial CdS nucleation on CdSe, leading to broad and multimodal particle size distributions. Critically, obtained core/shell sizes are often below those desired. This article describes synthetic conditions specific to thick-shell growth (n {ge} 10 and n {ge} 20 MLs) on both small (sub2 nm) and large (>4.5 nm) CdSe cores. We find added secondary amine and low concentration of CdSe cores and molecular precursors give desired core/shell sizes. Amine-induced, partial etching of CdSe cores results in apparent shell-thicknesses slightly beyond those desired, especially for very-thick shells (n {ge} 20 MLs). Thermal ripening and fast precursor injection lead to undesired homogeneous CdS nucleation and incomplete shell growth. Core/shells derived from small CdSe (1.9 nm) have longer PL lifetimes and more pronounced blinking at single-particle level compared with those derived from large CdSe (4.7 nm). We expect our new synthetic approach will lead to a larger throughput of these materials, increasing their availability for fundamental studies and applications.

  10. Synthesis of CdSe quantum dots for quantum dot sensitized solar cell

    SciTech Connect (OSTI)

    Singh, Neetu, E-mail: singh.neetu1985@gmail.com; Kapoor, Avinashi [Department of Electronic Science, University of Delhi South Campus, New Delhi-110 021 (India); Kumar, Vinod [Department of Physics, University of the Free State, Bloemfontein, ZA9300 (South Africa); Mehra, R. M. [School of Engineering and Technology, Sharda University, Greater Noida-201 306, U.P. (India)

    2014-04-24T23:59:59.000Z

    CdSe Quantum Dots (QDs) of size 0.85 nm were synthesized using chemical route. ZnO based Quantum Dot Sensitized Solar Cell (QDSSC) was fabricated using CdSe QDs as sensitizer. The Pre-synthesized QDs were found to be successfully adsorbed on front ZnO electrode and had potential to replace organic dyes in Dye Sensitized Solar Cells (DSSCs). The efficiency of QDSSC was obtained to be 2.06 % at AM 1.5.

  11. Thermoelectric properties of p-type (Bi{sub 1{minus}x}Sb{sub x}){sub 2}Te{sub 3} fabricated by mechanical alloying process

    SciTech Connect (OSTI)

    Jung, B.Y.; Choi, J.S.; Oh, T.S.; Hyun, D.B.

    1997-07-01T23:59:59.000Z

    Thermoelectric properties of polycrystalline (Bi{sub 1{minus}x}Sb{sub x}){sub 2}Te{sub 3} (0.75 {le} x {le} 0.85), fabricated by mechanical alloying and hot pressing methods, have been investigated. Formation of (Bi{sub 0.25}Sb{sub 0.75}){sub 2}Te{sub 3} alloy powder was completed by mechanical alloying for 5 hours at ball-to-material ratio of 5:1, and processing time for (Bi{sub 1{minus}sub x}Sb{sub x}){sub 2}Te{sub 3} formation increased with Sb{sub 2}Te{sub 3} content x. When (Bi{sub 0.25}Sb{sub 0.75}){sub 2}Te{sub 3} was hot pressed at temperatures ranging from 300 C to 550 C for 30 minutes, figure-of-merit increased with hot pressing temperature and maximum value of 2.8 x 10{sup {minus}3}/K could be obtained by hot pressing at 550 C. When hot pressed at 550 C, (Bi{sub 0.2}Sb{sub 0.8}){sub 2}Te{sub 3} exhibited figure-of-merit of 2.92 x 10{sup {minus}3}/K, which could be improved to 2.97 x 10{sup {minus}3}/K with addition of 1 wt% Sb as acceptor dopant.

  12. Results of the BiPo-1 prototype for radiopurity measurements for the SuperNEMO double beta decay source foils

    SciTech Connect (OSTI)

    A. J. Caffrey; C. L. Ridle

    2010-10-01T23:59:59.000Z

    The development of BiPo detectors is dedicated to the measurement of extremely high radiopurity in 208Tl and 214Bi for the SuperNEMO double beta decay source foils. A modular prototype, called BiPo-1, with 0.8m2 of sensitive surface area, has been running in the Modane Underground Laboratory since February, 2008. The goal of BiPo-1 is to measure the different components of the background and in particular the surface radiopurity of the plastic scintillators that make up the detector. The first phase of data collection has been dedicated to the measurement of the radiopurity in 208Tl. After more than one year of background measurement, a surface activity of the scintillators of Ađ208TlŢ Ľ 1:5mBq=m2 is reported here. Given this level of background, a larger BiPo detector having 12m2 of active surface area, is able to qualify the radiopurity of the SuperNEMO selenium double beta decay foils with the required sensitivity of Ađ208TlŢo2mBq=kg (90% C.L.) with a six month measurement.

  13. Results of the BiPo-1 prototype for radiopurity measurements for the SuperNEMO double beta decay source foils

    E-Print Network [OSTI]

    Argyriades, J; Augier, C; Baker, J; Barabash, A S; Basharina-Freshville, A; Bongrand, M; Bourgeois, C; Breton, D; Briére, M; Broudin-Bay, G; Brudanin, V B; Caffrey, A J; Cebrián, S; Chapon, A; Chauveau, E; Dafni, Th; Díaz, J; Durand, D; Egorov, V G; Evans, J J; Flack, R; Fushima, K-I; Irastorza, I G; Garrido, X; Gómez, H; Guillon, B; Holin, A; Holy, K; Horkey, J J; Hubert, P; Hugon, C; Iguaz, F J; Ishihara, N; Jackson, C M; Jenzer, S; Jullian, S; Kauer, M; Kochetov, O I; Konovalov, S I; Kovalenko, V; Lamhamdi, T; Lang, K; Lemiére, Y; Lutter, G; Luzón, G; Mamedov, F; Marquet, Ch; Mauger, F; Monrabal, F; Nachab, A; Nemchenok, I B; Nguyen, C H; Nomachi, M; Nova, F; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Povinec, P P; Richards, B; Ricol, J S; Riddle, C L; Rodríguez, A; Saakyan, R; Sarazin, X; Sedgbeer, J K; Serra, L; Shitov, Yu A; Simard, L; Šimkovic, F; Söldner-Rembold, S; Štekl, I; Sutton, C S; Tamagawa, Y; Szklarz, G; Thomas, J; Timkin, V; Tretyak, V; Tretyak, Vl I; Umatov, V I; Vála, L; Vanyushin, I A; Vasiliev, R; Vasiliev, V A; Vorobel, V; Waters, D; Yahali, N; Žukauskas, A

    2010-01-01T23:59:59.000Z

    The development of BiPo detectors is dedicated to the measurement of extremely high radiopurity in $^{208}$Tl and $^{214}$Bi for the SuperNEMO double beta decay source foils. A modular prototype, called BiPo-1, with 0.8 $m^2$ of sensitive surface area, has been running in the Modane Underground Laboratory since February, 2008. The goal of BiPo-1 is to measure the different components of the background and in particular the surface radiopurity of the plastic scintillators that make up the detector. The first phase of data collection has been dedicated to the measurement of the radiopurity in $^{208}$Tl. After more than one year of background measurement, a surface activity of the scintillators of $\\mathcal{A}$($^{208}$Tl) $=$ 1.5 $\\mu$Bq/m$^2$ is reported here. Given this level of background, a larger BiPo detector having 12 m$^2$ of active surface area, is able to qualify the radiopurity of the SuperNEMO selenium double beta decay foils with the required sensitivity of $\\mathcal{A}$($^{208}$Tl) $<$ 2 $\\mu$...

  14. On the equivalence of dynamically orthogonal and bi-orthogonal methods: Theory and numerical simulations

    SciTech Connect (OSTI)

    Choi, Minseok [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States); Sapsis, Themistoklis P. [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Karniadakis, George Em, E-mail: george_karniadakis@brown.edu [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States)

    2014-08-01T23:59:59.000Z

    The Karhunen–Lňeve (KL) decomposition provides a low-dimensional representation for random fields as it is optimal in the mean square sense. Although for many stochastic systems of practical interest, described by stochastic partial differential equations (SPDEs), solutions possess this low-dimensional character, they also have a strongly time-dependent form and to this end a fixed-in-time basis may not describe the solution in an efficient way. Motivated by this limitation of standard KL expansion, Sapsis and Lermusiaux (2009) [26] developed the dynamically orthogonal (DO) field equations which allow for the simultaneous evolution of both the spatial basis where uncertainty ‘lives’ but also the stochastic characteristics of uncertainty. Recently, Cheng et al. (2013) [28] introduced an alternative approach, the bi-orthogonal (BO) method, which performs the exact same tasks, i.e. it evolves the spatial basis and the stochastic characteristics of uncertainty. In the current work we examine the relation of the two approaches and we prove theoretically and illustrate numerically their equivalence, in the sense that one method is an exact reformulation of the other. We show this by deriving a linear and invertible transformation matrix described by a matrix differential equation that connects the BO and the DO solutions. We also examine a pathology of the BO equations that occurs when two eigenvalues of the solution cross, resulting in an instantaneous, infinite-speed, internal rotation of the computed spatial basis. We demonstrate that despite the instantaneous duration of the singularity this has important implications on the numerical performance of the BO approach. On the other hand, it is observed that the BO is more stable in nonlinear problems involving a relatively large number of modes. Several examples, linear and nonlinear, are presented to illustrate the DO and BO methods as well as their equivalence.

  15. Manipulation of subsurface carbon nanoparticles in Bi?Sr?CaCu?O8+? using a scanning tunneling microscope

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

    Stollenwerk, A. J.; Gu, G.; Hurley, N.; Beck, B.; Spurgeon, K.; Kidd, T. E.

    2015-03-01T23:59:59.000Z

    We present evidence that subsurface carbon nanoparticles in Bi?Sr?CaCu?O8+? can be manipulated with nanometer precision using a scanning tunneling microscope. High resolution images indicate that most of the carbon particles remain subsurface after transport observable as a local increase in height as the particle pushes up on the surface. Tunneling spectra in the vicinity of these protrusions exhibit semiconducting characteristics with a band gap of approximately 1.8 eV, indicating that the incorporation of carbon locally alters the electronic properties near the surface.

  16. Measuring bi-directional current through a field-effect transistor by virtue of drain-to-source voltage measurement

    DOE Patents [OSTI]

    Turner, Steven Richard

    2006-12-26T23:59:59.000Z

    A method and apparatus for measuring current, and particularly bi-directional current, in a field-effect transistor (FET) using drain-to-source voltage measurements. The drain-to-source voltage of the FET is measured and amplified. This signal is then compensated for variations in the temperature of the FET, which affects the impedance of the FET when it is switched on. The output is a signal representative of the direction of the flow of current through the field-effect transistor and the level of the current through the field-effect transistor. Preferably, the measurement only occurs when the FET is switched on.

  17. Technical evaluation and assessment of CNG/LPG bi-fuel and flex-fuel vehicle viability

    SciTech Connect (OSTI)

    Sinor, J E [Sinor (J.E.) Consultants, Inc., Niwot, CO (United States)

    1994-05-01T23:59:59.000Z

    This report compares vehicles using compressed natural gas (CNG), liquefied petroleum gas (LPG), and combinations of the two in bi-fuel or flex-fuel configurations. Evidence shows that environmental and energy advantages can be gained by replacing two-fuel CNG/gasoline vehicles with two-fuel or flex-fuel systems to be economically competitive, it is necessary to develop a universal CNG/LPG pressure-regulator-injector and engine control module to switch from one tank to the other. For flex-fuel CNG/LPG designs, appropriate composition sensors, refueling pumps, fuel tanks, and vaporizers are necessary.

  18. Diffraction anomalous fine structure analysis on (Bi,Pb){sub 2}PtO{sub 4} powders

    SciTech Connect (OSTI)

    Vacinova, J. [Centre National de la Recherche Scientifique (CNRS), 38 - Grenoble (France). Lab. de Cristallographie; Hodeau, J.L.; Bordet, P. [European Synchrotron Radiation Facility, 38 - Grenoble (France)] [and others

    1995-12-31T23:59:59.000Z

    The Diffraction Anomalous Fine Structure (DAFS) method can provide site selective and chemical selective structural information. The possibilities of DAFS experimental and data analysis procedures are demonstrated for (Bi{sub 1.67},Pb{sub 0.33}) powder samples. Experiments have been performed at both L{sub III} and K Pt edges (11.56.564keV and 78keV), using several data collection set-ups (analyser crystals, 1D-detector, 2D-detector). Based on this example, a comparison between these experimental procedures and analysis is given and discussed.

  19. Study on neutronic of very small Pb - Bi cooled no-onsite refueling nuclear power reactor (VSPINNOR)

    SciTech Connect (OSTI)

    Arianto, Fajar, E-mail: ariantofajar@gmail.com [Laboratory of Nuclear and Biophysics, Department of Physics, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132, Indonesia and Laboratory of Atom and Nuclear, Department of Physics, Diponegoro University, Jl. Prof. Soedarto, S.H., Tembala (Indonesia); Su'ud, Zaki, E-mail: szaki@fi.itba.c.id [Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Science, Bandung Institute of Technology (Ganesha 10 Bandung, Indonesia) (Indonesia); Zuhair [Center for Reactor Technology and Nuclear Safety, National Nuclear Energy Agency, Kawasan Puspiptek, Gedung No. 80, Serpong, Tangerang 15310 (Indonesia)

    2014-09-30T23:59:59.000Z

    A conceptual design study on Very Small Pb-Bi No-Onsite Refueling Cooled Nuclear Reactor (VSPINNOR) with Uranium nitride fuel using MCNPX program has been performed. In this design the reactor core is divided into three regions with different enrichment. At the center of the core is laid fuel without enrichment (internal blanket). While for the outer region using fuel enrichment variations. VSPINNOR fast reactor was operated for 10 years without refueling. Neutronic analysis shows optimized result of VSPINNOR has a core of 50 cm radius and 100 cm height with 300 MWth thermal power output at 60% fuel fraction that can be operated 18 years without refueling or fuel shuffling.

  20. Structure and ferroelectricity of nonstoichiometric (Na{sub 0.5}Bi{sub 0.5})TiO{sub 3}

    SciTech Connect (OSTI)

    Carter, Jared [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Aksel, Elena [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Graduate School of Science and Technology, Tokyo Institute of Technology, Tokyo 152–8552 (Japan); Iamsasri, Thanakorn; Forrester, Jennifer S.; Jones, Jacob L. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Chen, Jun [Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083 (China)

    2014-03-17T23:59:59.000Z

    Stoichiometric (Na{sub 0.5}Bi{sub 0.5})TiO{sub 3} (NBT) adopts the ABO{sub 3} perovskite structure with the A-site equally occupied by Na{sup +} and Bi{sup 3+} ions. However, non-stoichiometric compositions can be synthesized intentionally or unintentionally. To determine the effect of A-site nonstoichiometry on the crystal structure and ferroelectricity of NBT, the composition of (Na{sub 0.5?x}Bi{sub 0.5+x})TiO{sub 3+x} was varied using x?=??0.01, ?0.005, 0, 0.005, and 0.01. High resolution synchrotron x-ray diffraction and Rietveld refinement revealed that a shift in either direction from x = 0 results in a decrease in the spontaneous ferroelastic strain. Ferroelectric hysteresis and piezoelectric coefficients were found to be optimum in the stoichiometric composition.

  1. Novel Approaches to Wide Bandgap CuInSe2 Based Absorbers

    SciTech Connect (OSTI)

    William N. Shafarman

    2011-04-28T23:59:59.000Z

    This project targeted the development of high performance wide bandgap solar cells based on thin film alloys of CuInSe2 to relax constraints on module design and enable tandem solar cell structures. This addressed goals of the Solar Energy Technologies Program for Next Generation PV to develop technology needed for higher thin film module efficiency as a means to reduce costs. Specific objectives of the research project were: 1) to develop the processes and materials required to improve the performance of wide bandgap thin film solar cells based on alloys of CuInSe2, and 2) to provide the fundamental science and engineering basis for the material, electronic, and device properties required to effectively apply these processes and materials to commercial manufacture. CuInSe2-based photovoltaics have established the highest efficiencies of the thin film materials at both the cell and module scales and are actively being scaled up to commercialization. In the highest efficiency cells and modules, the optical bandgap, a function of the CuInSe2-based alloy composition, is relatively low compared to the optimum match to the solar spectrum. Wider bandgap alloys of CuInSe2 produce higher cell voltages which can improve module performance and enable the development of tandem solar cells to boost the overall efficiency. A focus for the project was alloying with silver to form (AgCu)(InGa)Se2 pentenary thin films deposited by elemental co-evaporation which gives the broadest range of control of composition and material properties. This alloy has a lower melting temperature than Ag-free, Cu-based chalcopyrite compounds, which may enable films to be formed with lower defect densities and the (AgCu)(InGa)Se2 films give improved material properties and better device performance with increasing bandgap. A comprehensive characterization of optical, structural, and electronic properties of (AgCu)(InGa)Se2 was completed over the complete compositional range 0 ? Ga/(In+Ga) ? 1 and 0 ? Ag/(Ag+Cu) ? 1. Evidence of improved material quality includes reduced sub-bandgap optical absorption, sharper bandtails, and increased grain size with Ag addition. The Ag alloying was shown to increase the range of bandgaps over which solar cells can be fabricated without any drop-off in performance. With bandgap greater than 1.6 eV, in the range needed for tandem solar cells, (AgCu)(InGa)Se2 gave higher efficiency than other CuInSe2-based alloys. Using a simple single-stage co-evaporation process, a solar cell with 17.6% efficiency using a film with bandgap = 1.3 eV was achieved, demonstrating the viability of (AgCu)(InGa)Se2 for high efficiency devices. With a three-stage co-evaporation process for (AgCu)(InGa)Se2 deposition a device with efficiency = 13.0 % and VOC = 890 mV with JSC = 20.5 mA/cm2, FF = 71.3% was achieved. This surpasses the performance of other wide bandgap CuInSe2-based solar cells. Detailed characterization of the electronic properties of the materials and devices including the application of advanced admittance-based easements was completed.

  2. Superconductivity up to 110 K in Bi2Sr2Ca2Cu3O10 compounds P. Lejay (1), P. de Rango (1), A. Sulpice (1), B. Giordanengo (1), R. Tournier (1), R. Retoux (2),

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    than 50 % for the samples doped with Pb. Because of the high reversibility of the magnetization versus. 2014 In the Bi-Sr-Ca-Cu-O system, we have studied the compound with the ideal formula Bi2Sr2Ca2Cu3O10, responsible for the superconductivity up to 110 K. The magnetic measurements reveal the presence of two phases

  3. Advances in SiGe HBT BiCMOS Technology A. Joseph, L. Lanzerotti, X. Liu, D. Sheridan, J. Johnson, Q. Liu, J. Dunn, J.-S. Rieh*, and D. Harame

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    Advances in SiGe HBT BiCMOS Technology A. Joseph, L. Lanzerotti, X. Liu, D. Sheridan, J. Johnson, Q Email: josepha@us.ibm.com, Phone: 802-769-469 Abstract -- Silicon Germanium (SiGe) Heterojunction marketplace by offering a cost competitive solution for myriad of products. SiGe BiCMOS technologies currently

  4. Study of Gd-doped Bi{sub 2}Te{sub 3} thin films: Molecular beam epitaxy growth and magnetic properties

    SciTech Connect (OSTI)

    Harrison, S. E.; Huo, Y.; Harris, J. S. [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Collins-McIntyre, L. J.; Hesjedal, T., E-mail: Thorsten.Hesjedal@physics.ox.ac.uk [Department of Physics, Clarendon Laboratory, University of Oxford, Oxford OX1 3PU (United Kingdom); Li, S. [Department of Physics, Stanford University, Stanford, California 94305 (United States); Baker, A. A. [Department of Physics, Clarendon Laboratory, University of Oxford, Oxford OX1 3PU (United Kingdom); Magnetic Spectroscopy Group, Diamond Light Source, Didcot, Oxfordshire OX11 0DE (United Kingdom); Shelford, L. R.; Laan, G. van der [Magnetic Spectroscopy Group, Diamond Light Source, Didcot, Oxfordshire OX11 0DE (United Kingdom); Pushp, A.; Parkin, S. S. P. [IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120 (United States); Arenholz, E. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2014-01-14T23:59:59.000Z

    Incorporation of magnetic dopants into topological insulators to break time-reversal symmetry is a prerequisite for observing the quantum anomalous Hall (QAHE) effect and other novel magnetoelectric phenomena. GdBiTe{sub 3} with a Gd:Bi ratio of 1:1 is a proposed QAHE system, however, the reported solubility limit for Gd doping into Bi{sub 2}Te{sub 3} bulk crystals is between ?0.01 and 0.05. We present a magnetic study of molecular beam epitaxy grown (Gd{sub x}Bi{sub 1–x}){sub 2}Te{sub 3} thin films with a high Gd concentration, up to x ? 0.3. Magnetometry reveals that the films are paramagnetic down to 1.5?K. X-ray magnetic circular dichroism at the Gd M{sub 4,5} edge at 1.5?K reveals a saturation field of ?6?T, and a slow decay of the magnetic moment with temperature up to 200?K. The Gd{sup 3+} ions, which are substitutional on Bi sites in the Bi{sub 2}Te{sub 3} lattice, exhibit a large atomic moment of ?7??{sub B}, as determined by bulk-sensitive superconducting quantum interference device magnetometry. Surface oxidation and the formation of Gd{sub 2}O{sub 3} lead to a reduced moment of ?4??{sub B} as determined by surface-sensitive x-ray magnetic circular dichroism. Their large atomic moment makes these films suitable for incorporation into heterostructures, where interface polarization effects can lead to the formation of magnetic order within the topological insulators.

  5. Ferroelectric and ferromagnetic properties of epitaxial BiFeO{sub 3}-BiMnO{sub 3} films on ion-beam-assisted deposited TiN buffered flexible Hastelloy

    SciTech Connect (OSTI)

    Xiong, J., E-mail: jiexiong@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Los Alamos National Laboratory, Center for Integrated Nanotechnologies, Division of Materials Physics and Applications, Los Alamos, New Mexico 87545 (United States); Matias, V.; Jia, Q. X. [Los Alamos National Laboratory, Center for Integrated Nanotechnologies, Division of Materials Physics and Applications, Los Alamos, New Mexico 87545 (United States); Tao, B. W.; Li, Y. R. [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2014-05-07T23:59:59.000Z

    Growth of multifunctional thin films on flexible substrates is of great technological significance since such a platform is needed for flexible electronics. In this study, we report the growth of biaxially aligned (BiFeO{sub 3}){sub 0.5}:(BiMnO{sub 3}){sub 0.5} [BFO-BMO] films on polycrystalline Hastelloy by using a biaxially aligned TiN as a seed layer deposited by ion-beam-assisted deposited and a La{sub 0.7}Sr{sub 0.3}MnO{sub 3} (LSMO) as a buffer layer deposited by pulsed laser deposition. The LSMO is used not only as a buffer layer but also as the bottom electrode of the BFO-BMO films. X-ray diffraction showed that the BFO-BMO films are biaxially oriented along both in-plane and out-of-plane directions. The BFO-BMO films on flexible metal substrates showed a polarization of 22.9??C/cm{sup 2}. The magnetization of the BFO-BMO/LSMO is 62?emu/cc at room temperature.

  6. The enhancement of thermoelectric power and scattering of carriers in Bi{sub 2{minus}x}Sn{sub x}Te{sub 3} single crystals

    SciTech Connect (OSTI)

    Kulbachinskii, V.A.; Negishi, H.; Sasaki, M.; Giman, Y.; Inoue, M.

    1997-07-01T23:59:59.000Z

    Thermoelectric power, electrical resistivity, and Hall effect of p-type Bi{sub 2{minus}x}Sn{sub x}Te{sub 3} (0 < x < 0.03) singlecrystals have been measured in the temperature range 4.2--300K. By doping of Sn atoms into the host Bi{sub 2}Te{sub 3} lattice, the enhancement in the thermoelectric power is observed in the intermediate temperature range 30--150K for x {le} 0,0075. The activation type behavior of Hall coefficient and resistivity are found which corresponds to the Sn-induced impurity band located above the second lower valence band.

  7. Optically pumped quantum-dot Cd(Zn)Se/ZnSe laser and microchip converter for yellow-green spectral region

    SciTech Connect (OSTI)

    Lutsenko, E V; Voinilovich, A G; Rzheutskii, N V; Pavlovskii, V N; Yablonskii, G P; Sorokin, S V; Gronin, S V; Sedova, I V; Kop'ev, Petr S; Ivanov, Sergei V; Alanzi, M; Hamidalddin, A; Alyamani, A

    2013-05-31T23:59:59.000Z

    The room temperature laser generation in the yellow-green ({lambda} = 558.5-566.7 nm) spectral range has been demonstrated under optical pumping by a pulsed nitrogen laser of Cd(Zn)Se/ZnSe quantum dot heterostructures. The maximum achieved laser wavelength was as high as {lambda} = 566.7 nm at a laser cavity length of 945 {mu}m. High values of both the output pulsed power (up to 50 W) and the external differential quantum efficiency ({approx}60%) were obtained at a cavity length of 435 {mu}m. Both a high quality of the laser heterostructure and a low lasing threshold ({approx}2 kW cm{sup -2}) make it possible to use a pulsed InGaN laser diode as a pump source. A laser microchip converter based on this heterostructure has demonstrated a maximum output pulse power of {approx}90 mW at {lambda} = 560 nm. The microchip converter was placed in a standard TO-18 (5.6 mm in diameter) laser diode package. (semiconductor lasers. physics and technology)

  8. A Novel and Functional Single Layer Sheet of ZnSe

    SciTech Connect (OSTI)

    Zhou, Jia [ORNL; Sumpter, Bobby G [ORNL; Kent, Paul R [ORNL; Huang, Jingsong [ORNL

    2015-01-01T23:59:59.000Z

    In this Communication, we report a novel singlelayer sheet of ZnSe, with a three-atomic thickness, which demonstrates a strong quantum confinement effect by exhibiting a large blue shift of 2.0 eV in its absorption edge relative to the zinc blende (ZB) bulk phase. Theoretical optical absorbance shows that the largest absorption of this ultrathin single-layer sheet of ZnSe occurs at a wavelength similar to its four-atom-thick doublelayer counterpart but with higher photoabsorption efficiency, suggesting a superior behavior on incident photon-to-current conversion efficiency for solar water splitting, among other potential applications. The results presented herein for ZnSe may be generalized to other group II-VI analogues.

  9. Critical Fields, Thermally Activated Transport, and Critical Current Density of Beta-FeSe Single Crystals

    SciTech Connect (OSTI)

    Petrovic, C.; Lei, H.; Hu, R.

    2011-07-27T23:59:59.000Z

    We present critical fields, thermally activated flux flow (TAFF), and critical current density of tetragonal phase {beta}-FeSe single crystals. The upper critical fields H{sub c2}(T) for H {parallel} (101) and H {perpendicular} (101) are nearly isotropic and are likely governed by the Pauli limiting process. The large Ginzburg-Landau parameter {Kappa} {approx} 72.3(2) indicates that {beta}-FeSe is a type-II superconductor with a smaller penetration depth than in Fe(Te, Se). The resistivity below T{sub c} follows Arrhenius TAFF behavior. For both field directions below 30 kOe, single-vortex pinning is dominant, whereas collective creep becomes important above 30 kOe. The critical current density J{sub c} from M-H loops for H {parallel} (101) is about five times larger than for H {perpendicular} (101), yet much smaller than in other iron-based superconductors.

  10. Recrystallization method to selenization of thin-film Cu(In,Ga)Se.sub.2 for semiconductor device applications

    DOE Patents [OSTI]

    Albin, David S. (Denver, CO); Carapella, Jeffrey J. (Evergreen, CO); Tuttle, John R. (Denver, CO); Contreras, Miguel A. (Golden, CO); Gabor, Andrew M. (Boulder, CO); Noufi, Rommel (Golden, CO); Tennant, Andrew L. (Denver, CO)

    1995-07-25T23:59:59.000Z

    A process for fabricating slightly Cu-poor thin-films of Cu(In,Ga)Se.sub.2 on a substrate for semiconductor device applications includes the steps of forming initially a slightly Cu-rich, phase separated, mixture of Cu(In,Ga)Se.sub.2 :Cu.sub.x Se on the substrate in solid form followed by exposure of the Cu(In,Ga)Se.sub.2 :Cu.sub.x Se solid mixture to an overpressure of Se vapor and (In,Ga) vapor for deposition on the Cu(In,Ga)Se.sub.2 :Cu.sub.x Se solid mixture while simultaneously increasing the temperature of the solid mixture toward a recrystallization temperature (about 550.degree. C.) at which Cu(In,Ga)Se.sub.2 is solid and Cu.sub.x Se is liquid. The (In,Ga) flux is terminated while the Se overpressure flux and the recrystallization temperature are maintained to recrystallize the Cu.sub.x Se with the (In, Ga) that was deposited during the temperature transition and with the Se vapor to form the thin-film of slightly Cu-poor Cu.sub.x (In,Ga).sub.y Se.sub.z. The initial Cu-rich, phase separated large grain mixture of Cu(In,Ga)Se.sub.2 :Cu.sub.x Se can be made by sequentially depositing or co-depositing the metal precursors, Cu and (In, Ga), on the substrate at room temperature, ramping up the thin-film temperature in the presence of Se overpressure to a moderate anneal temperature (about 450.degree. C.) and holding that temperature and the Se overpressure for an annealing period. A nonselenizing, low temperature anneal at about 100.degree. C. can also be used to homogenize the precursors on the substrates before the selenizing, moderate temperature anneal.

  11. Thermodynamic Model for the Solubility of Ba(SeO4, SO4) Precipitates

    SciTech Connect (OSTI)

    Rai, D.; Felmy, Andrew R.; Moore, Dean A.; Kitamura, Akira; Yoshikawa, Hideki; Doi, Reisuke; Yoshida, Yasushi

    2014-08-15T23:59:59.000Z

    Abstract: The solubility of Ba(SeO4, SO4) precipitates was determined as a function of the BaSeO4 mole fractions, ranging from 0.0015 to 0.3830, and time with an equilibration period extending to as long as 302 days. Equilibrium/steady state conditions in this system are reached in ? 65 days. Pitzer’s ion interaction model was used to calculate solid and aqueous phase activity coefficients. Thermodynamic analyses showed that the data do not satisfy Gibbs-Duhem equation, thereby demonstrating that a single-solid solution phase does not control both the selenate and sulfate concentrations. Our extensive data with log 10 [Ba] ranging from ?3.6 to ?5.9 mol kg?1, log 10 [SeO4] rangingfrom?3.6 to -5.2 mol kg?1, and log 10 [SO4] ranging from?4.0 to ?5.3 mol kg?1 can be explained with the formation of an ideal BaSeO4 solid solution phase that controls the selenium concentrations and a slightly disordered/less-crystalline BaSO4(s) (log 10𝐾?sp = ?9.5 instead of ?10.05 for barite) that controls the sulfate concentrations. In these experiments the BaSO4 component of the solid solution phase never reaches thermodynamic equilibrium with the aqueous phase. Thermodynamic interpretations of the data show that both the ideal BaSeO4 solid solution phase and less-crystalline BaSO4 (s) phase are in equilibrium with each other in the entire range of BaSeO 4 mole fractions investigated in this study.

  12. Speciation, characterization, and mobility of As, Se, and Hg in flue gas desulphurization residues

    SciTech Connect (OSTI)

    Souhail R. Al-Abed; Gautham Jegadeesan; Kirk G. Scheckel; Thabet Tolaymat [United States Environmental Protection Agency, Cincinnati, OH (United States). National Risk Management Research Laboratory

    2008-03-01T23:59:59.000Z

    Flue gas from coal combustion contains significant amounts of volatile toxic trace elements such as arsenic (As), selenium (Se), and mercury (Hg). The capture of these elements in the flue gas desulphurization (FGD) scrubber unit has resulted in generation of a metal-laden residue. With increasing reuse of the FGD residues in beneficial applications, it is important to determine metal speciation and mobility to understand the environmental impact of its reuse. In this paper, we report the solid phase speciation of As, Se, and Hg in FGD residues using X-ray absorption spectroscopy (XAS), X-ray fluorescence spectroscopy (XRF), and sequential chemical extraction (SCE) techniques. The SCE results combined with XRF data indicated a strong possibility of As association with iron oxides, whereas Se was distributed among all geochemical phases. Hg appeared to be mainly distributed in the strong-complexed phase. XRF images also suggested a strong association of Hg with Fe oxide materials within FGD residues. XAS analysis indicated that As existed in its oxidized state (As(V)), whereas Se and Hg was observed in primarily reduced states as selenite (Se(IV)) and Hg(I), respectively. The results from the SCE and variable pH leaching tests indicated that the labile fractions of As, Se, and Hg were fairly low and thus suggestive of their stability in the FGD residues. However, the presence of a fine fraction enriched in metal content in the FGD residue suggested that size fractionation is important in assessing the environmental risks associated with their reuse. 34 refs., 3 figs., 4 tabs.

  13. Ann bay lodyans 3 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 3 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvčl : Fondasyon Alfa Lwčs, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAY LODYANS 3 Se Bryant Freeman...

  14. Ann bay lodyans 16 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 16 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvčl : Fondasyon Alfa Lwčs, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAYL0DYANS16 Yon Ti Degi Se Bryant...

  15. Ann bay lodyans 1 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 1 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvčl : Fondasyon Alfa Lwčs, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAY LODYANS 1 Se Bryant Freeman...

  16. Ann bay lodyans 8 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    dlo." Eklid Etyen, Teryewouj 1 2 TI GOUT TI GOUT, KONPE CHAT PEDI Yon jou diskisyon mete pye ant konpe Chen ak konpe Chat. Te gen yon moso vyann ate a. Konpe Chen di se li menm ki te we I anvan, men konpe Chat di se li menm ki te we I anvan... mak sonje. Konsa, Chat ale kay yon boko. Li di: "Papa, m vin lakay ou pou touye tout chen ki gen sou late. M ap peye ou mezi ou vie pou sa." Boko a reponn: "A monche, m ap ba ou sa sou de chez. Eske ou ka jwenn yon ti gout pipi chen?" Konpe Chat...

  17. Investigations of CuInSe sub 2 thin films and contacts

    SciTech Connect (OSTI)

    Nicolet, M.A. (California Inst. of Tech., Pasadena, CA (United States))

    1991-10-01T23:59:59.000Z

    This report describes research into electrical contacts for copper indium diselenide (CuInSe{sub 2}) polycrystalline thin films used for solar cell applications. Molybdenum contacts have historically been the most promising for heterojunction solar cells. This program studied contact stability by investigating thermally induced bilayer reactions between molybdenum and copper, indium, and selenium. Because selenization is widely used to fabricate CuInSe{sub 2} thin films for photovoltaic cells, a second part of the program investigated how the morphologies, phases, and reactions of pre-selenization Cu-In structures are affected by the deposition process and heat treatments. 7 refs., 6 figs.

  18. Ann bay lodyans 2 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 2 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Communication and Copyright. Please share your stories about how Open Access to this article benefits you. This is the published version of the book, made available with the permission of the publisher. Freeman, Bryant C., ed. Ann bay lodyans 2 / se Bryant...

  19. Ann bay lodyans 5 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 5 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Communication and Copyright. Please share your stories about how Open Access to this article benefits you. This is the published version of the book, made available with the permission of the publisher. Freeman, Bryant C., ed. Ann bay lodyans 5 / se Bryant...

  20. Ann bay lodyans 4 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 4 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvčl : Fondasyon Alfa Lwčs, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml Tl CHAT: PI PITI PI RED Vwala se te...

  1. Ann bay lodyans 15 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 15 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvčl : Fondasyon Alfa Lwčs, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAY LODYANS15 Se Bryant Freeman...

  2. Ann bay lodyans 6 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 6 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvčl : Fondasyon Alfa Lwčs, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAYLODYANS g Se Bryant Freeman...

  3. Pair correlations in nuclei involved in neutrinoless double beta decay: 76Ge and 76Se

    E-Print Network [OSTI]

    S. J. Freeman; J. P. Schiffer; A. C. C. Villari; J. A. Clark; C. Deibel; S. Gros; A. Heinz; D. Hirata; C. L. Jiang; B. P. Kay; A. Parikh; P. D. Parker; J. Qian; K. E. Rehm; X. D. Tang; V. Werner; C. Wrede

    2007-03-23T23:59:59.000Z

    Precision measurements were carried out to test the similarities between the ground states of 76Ge and 76Se. The extent to which these two nuclei can be characterized as consisting of correlated pairs of neutrons in a BCS-like ground state was studied. The pair removal (p,t) reaction was measured at the far forward angle of 3 degrees. The relative cross sections are consistent (at the 5% level) with the description of these nuclei in terms of a correlated pairing state outside the N=28 closed shells with no pairing vibrations. Data were also obtained for 74Ge and 78Se.

  4. 186 VHDL: LENGUAJE PARA S INTESIS Y MODELADO DE CIRCUITOS c El cronograma correspondiente, como resultado de la simulacion, se muestra en la

    E-Print Network [OSTI]

    Valencia, Universidad de

    , como resultado de la simulaciâ??on, se muestra en la figura 12.6 donde se han incluido todas las se

  5. Supplemental Figure 1. Root lengths of S. pinnata and S. albescens grown on vertically placed agar plates after 30 days of growth from germination. Plants treated without () Se (open bars) and with (+) 20 M SeO4

    E-Print Network [OSTI]

    ) and with (+) 20 M SeO4 2- (gray bars). Data represent the average of 4-5 different plants ± SE. P-values using and S. albescens grown with or without 20 M SeO4 2- . The only significant difference between treatments. pinnata when compared with S. albescens grown with and without 20 M SeO4 2- . #12;Supplemental Figure 4

  6. Method of fabricating high-efficiency Cu(In,Ga)(Se,S){sub 2} thin films for solar cells

    DOE Patents [OSTI]

    Noufi, R.; Gabor, A.M.; Tuttle, J.R.; Tennant, A.L.; Contreras, M.A.; Albin, D.S.; Carapella, J.J.

    1995-08-15T23:59:59.000Z

    A process for producing a slightly Cu-poor thin film of Cu(In,Ga)(Se,S){sub 2} comprises depositing a first layer of (In,Ga){sub x} (Se,S){sub y} followed by depositing just enough Cu+(Se,S) or Cu{sub x} (Se,S) to produce the desired slightly Cu-poor material. In a variation, most, but not all, (about 90 to 99%) of the (In,Ga){sub x} (Se,S){sub y} is deposited first, followed by deposition of all the Cu+(Se,S) or Cu{sub x} (Se,S) to go near stoichiometric, possibly or even preferably slightly Cu-rich, and then in turn followed by deposition of the remainder (about 1 to 10%) of the (In,Ga){sub x} (Se,S){sub y} to end with a slightly Cu-poor composition. In yet another variation, a small portion (about 1 to 10%) of the (In,Ga){sub x} (Se,S){sub y} is first deposited as a seed layer, followed by deposition of all of the Cu+(Se,S) or Cu{sub x} (Se,S) to make a very Cu-rich mixture, and then followed deposition of the remainder of the (In,Ga){sub x} (Se,S){sub y} to go slightly Cu-poor in the final Cu(In,Ga)(Se,S){sub 2} thin film. 5 figs.

  7. Distance-Engineered Plasmon-Enhanced Light Harvesting in CdSe Quantum Dots

    E-Print Network [OSTI]

    Distance-Engineered Plasmon-Enhanced Light Harvesting in CdSe Quantum Dots Shengye Jin,,§, Erica De) is essential for the development of efficient QD-based solar energy conversion systems. In this study, plasmon as a function of interparticle (QD to Ag NP) distance. Up to 24-fold plasmonic enhancement of fluorescence from

  8. To appear in JSiSE, 18(2), 2001 July 30, 2001

    E-Print Network [OSTI]

    Matsuda, Noboru

    To appear in JSiSE, 18(2), 2001 July 30, 2001 1. (Intelligent Tutoring System: ITS) () "" 2. Graesser (1995) Chi (2001 to appear) #12;Graesser Chi Graesser 70 Chi Graesser Chi ITS ITS "" 3. (Graesser , 2001 to appear) - Building Dialogue Systems for Tutoring

  9. FI 10 19 dcembre 2006 page Alan Turing se fraye un chemin jusqu'

    E-Print Network [OSTI]

    Teuscher, Christof

    FI 10 ­ 19 décembre 2006 ­ page Alan Turing se fraye un chemin jusqu'ŕ la place de lPiccard,cheminJeanTschumi,avenueForel,rue RobertMercier,chemin, place ou rueAlanTuring. EtquefaisaitAlanTuringcheminfaisant?Leplus souvent,craqueurducodesecretdela machineEnigma?Certesexagéré,maisle succčsaplusieursparentsetAlanTuring estaumoinslegrandpčreoul

  10. From Bad to Worse: Senior economic inSecurity on the riSe

    E-Print Network [OSTI]

    Snider, Barry B.

    From Bad to Worse: Senior economic inSecurity on the riSe Tatjana Meschede Laura Sullivan Thomas the Senior Financial Stability Index, economic insecurity among senior households increased by one demographic groups, economic security of seniors has deteriorated further. Contrary to the popular belief

  11. Molecular Adsorption to LiMo3Se3 Nanowire Film Chemiresistors

    E-Print Network [OSTI]

    Chiang, Shirley

    Molecular Adsorption to LiMo3Se3 Nanowire Film Chemiresistors Xiubin Qi, Frank E. Osterloh,*, S. A that the temporal and steady-state resistance changes of the films depend on the time following the adsorption and on the number of molecules that adsorb to the nanowire films at a given pressure. The adsorption ability

  12. Hydrogen adsorption on Pd/TiFe (110) surface S.E. Kulkovaa

    E-Print Network [OSTI]

    Kim, Jai Sam

    Hydrogen adsorption on Pd/TiFe (110) surface S.E. Kulkovaa , S.V. Eremeeva,b,*, V.E. Egorushkinc February 2003 by E.L. Ivchenko Abstract Adsorption of hydrogen on the TiFe (110) surface covered the local density approximation. Influence of palladium coating to adsorption properties of the TiFe (110

  13. A n n u A l Campus seCurity And

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    A n n u A l Campus seCurity And Fire saFety report 2012 #12;Dear UC Santa Cruz Community, UC Santa are primarily responsible for ensuring the safety and security of the UC Santa Cruz community from all hazards in the responsibility of keeping our community safe. As such, we encourage you to read our Annual Campus Security

  14. Mn-Substituted Inorganic-Organic Hybrid Materials Based on ZnSe

    E-Print Network [OSTI]

    Li, Jing

    for optoelectronics and information storage technology. In this study, we demonstrate that the hybrid nanostructuresMn-Substituted Inorganic-Organic Hybrid Materials Based on ZnSe: Nanostructures That May Lead are highly desirable and extremely attractive in the development of new multifunctional devices

  15. Electrodeposition of CuGaSe2 from Thiocyanate-Containing Electrolytes

    E-Print Network [OSTI]

    Suni, Ian Ivar

    . Manuscript received September 8, 2010. Published December 2, 2010. CuInxGa1-xSe2 CIGS thin film solar cells- nation velocities.1 Thin film solar cells promise significant economic benefits, because the optical, electrochemical deposition methods may be significantly less expensive for scale-up of thin film solar cells,3

  16. Diffusion of indium and gallium in Cu(In,Ga)Se2 thin film solar cells

    E-Print Network [OSTI]

    Rockett, Angus

    conversion efficiency of solar cells made from this material [1]. One of the special qualities of the CIGS improve the solar cell performance. In many of the different CIGS fabrication techniques, an in depthDiffusion of indium and gallium in Cu(In,Ga)Se2 thin film solar cells O. Lundberga,*, J. Lua , A

  17. Mechanical impedance and CPX noise of SMA V.F. Vazquez and S.E. Paje

    E-Print Network [OSTI]

    Boyer, Edmond

    to the volume population affected, are transportation systems like motor vehicles. Tire road noise is the noiseMechanical impedance and CPX noise of SMA pavements V.F. V´azquez and S.E. Paje UCLM-LA2IC, Av 2012 Nantes Conference 23-27 April 2012, Nantes, France 167 #12;CPX noise is the sound measured

  18. Runions LMDZ6 se lancer dans la prparation des configuration futures,

    E-Print Network [OSTI]

    Madeleine, Jean-Baptiste

    . Première réunion improvisée au milieu de l'été parce qu'on se posait des questions sur le bout par lequel 19 paramètres, etc ...) - Changement de code radiatif et nouveaux forçages pour IPCC

  19. Photovoltaic effect in InSe Application to Solar Energy Conversion

    E-Print Network [OSTI]

    Boyer, Edmond

    253 Photovoltaic effect in InSe Application to Solar Energy Conversion A. Segura, J. P. Guesdon, JSe is shown to be a new material with attractive characteristics for solar energy conversion. PerformanceV at 300 K and it is thus close to the theoretical optimum for solar energy conversion. Since its transport

  20. SeRLoc: Secure Range-Independent Localization for Wireless Sensor Networks

    E-Print Network [OSTI]

    Hochberg, Michael

    SeRLoc: Secure Range-Independent Localization for Wireless Sensor Networks Loukas Lazos and Radha, radha}@ee.washington.edu ABSTRACT In many applications of wireless sensor networks (WSN), sensors Localization, Wireless sensor networks, range-independent This work was supported in part by the following

  1. RisNyt NO2 2005 I de kommende rtier vil vi se store

    E-Print Network [OSTI]

    fjerde i en se- rie, der sćtter energiemner i perspektiv pĺ globalt, regionalt og dansk niveau. Danmark har gode muligheder for at bevare fřrertrřjen I Danmark er vi allerede nĺet langt. Energi vigtigere rolle og isćr vindenergi er kraftigt udbygget. Samtidig kan Danmark fungere som en slags "buffer

  2. Polarized Luminescence of Defects in CuGaSe2 Susanne Siebentritt1,2

    E-Print Network [OSTI]

    Rockett, Angus

    ). But for the whole group of I-III-VI2 chalcopyrite semiconductors no reliable identification of native defects by ESR been found in CuInSe2. [14] In the effort of relating the energy positions of the defects to defect. Res. Soc. Symp. Proc. Vol. 1012 © 2007 Materials Research Society 1012-Y13-01 #12;the experiment

  3. 7900 SE 28th Street, Suite 200 Mercer, Island, WA 98040-2970

    E-Print Network [OSTI]

    7900 SE 28th Street, Suite 200 Mercer, Island, WA 98040-2970 v 206.236.7200 f 206.236.3019 www Administration. The Joint Proposal is a comprehensive settlement that will bring to an end the long costs, when the responsibility for reaching agreements with IPPs, is dispersed directly to the load

  4. Characterization of an FFDM unit based on a-Se direct conversion detector

    E-Print Network [OSTI]

    Lanconelli, Nico

    Characterization of an FFDM unit based on a-Se direct conversion detector Achille Albanese1 µm. The direct conversion of X-rays into charge provides excellent imaging performance. In this work, detectors based on a direct-conversion technology seem to give a better performance, especially at high

  5. A highly efficient (>6%) Cd1xMnxSe quantum dot sensitized solar cell

    E-Print Network [OSTI]

    Cao, Guozhong

    A highly efficient (>6%) Cd1ŔxMnxSe quantum dot sensitized solar cell Jianjun Tian,*a Lili Lv,a Chengbin Fei,b Yajie Wang,b Xiaoguang Liua and Guozhong Cao*bc Quantum dot sensitized solar cells (QDSCs-effective solar cell. The design and synthesis of quantum dots (QDs) for achieving high photoelectric performance

  6. Phonon and thermal properties of exfoliated TaSe2 thin films T. R. Pope,2

    E-Print Network [OSTI]

    films exfoliated from TaSe2 and other metal dichalcogenides, as well as for evaluating self-heating-Device Laboratory, Department of Electrical Engineering, Bourns College of Engineering, University of California its bulk value of $16 W/mK to $9 W/mK in 45-nm thick films. The measurement of electrical resistivity

  7. Xenosaurus phalaroanthereon: Edmica a Oaxaca y se distribuye en dos localidades en la

    E-Print Network [OSTI]

    Nacional Autónoma de México, Universidad

    Oficial Mexicana sólo se encuentran enlistadas tres de las especies que conforman el género (X. grandis, X concretas para su conservación y evaluar el estado de las poblaciones existentes. A pesar de que en la Norma:Xenosauridae) del sureste de Hidalgo, México. Boletín de la Sociedad Herpetológica Mexicana 15:20-22. Por: Luis

  8. Study of light-induced vector changes in the local atomic structure of AsSe glasses by EXAFS

    E-Print Network [OSTI]

    Drabold, David

    Study of light-induced vector changes in the local atomic structure of As­Se glasses by EXAFS G changes in the local structure of As­Se glasses using extended X-ray ab- sorption fine structure (EXAFS

  9. First-principles molecular-dynamics study of glassy As2Se3 Jun Li and D. A. Drabold

    E-Print Network [OSTI]

    Drabold, David

    static structure factor in the range 2­6 Ĺ 1 . The preferred structural unit is pyramidal AsSe3 loosely on the cluster model8 consisting mostly of pyramidal AsSe3 molecules,9 and the other is the layer structure using a molecular model and several vibrational frequencies were assigned to pyramidal AsSe3

  10. Heating-compensated constant-temperature tunneling measurements on stacks of Bi2Sr2CaCu2O8+x intrinsic junctions

    E-Print Network [OSTI]

    Lee, Hu-Jong

    measurements on a stack of intrinsic junctions IJs in a high-bias range are often susceptible to self-heating one to get rid of spurious tunneling effects arising from the self-heating. © 2005 American Institute. The poor thermal conductivity of the Bi-2212 IJs, how- ever, is known to cause serious local self-heating

  11. CVD Growth of Mono-and Bi-Layer Graphene from Ethanol Xiao Chen, Pei Zhao, Bo Hou, Erik Einarsson, Shohei Chiashi and Shigeo Maruyama

    E-Print Network [OSTI]

    Maruyama, Shigeo

    CVD Growth of Mono- and Bi-Layer Graphene from Ethanol Xiao Chen, Pei Zhao, Bo Hou, Erik Einarsson precursors have been employed to synthesize graphene, such as methane [6], ethane [7] and ethanol [8]. Here we report a systematic study on CVD growth of graphene on Cu and Ni substrates from ethanol. Ethanol

  12. Abstract--A bi-objective optimization model of power and power changes generated by a wind turbine is discussed in this

    E-Print Network [OSTI]

    Kusiak, Andrew

    operating a variable-speed wind turbine with pitch control to maximize power while minimizing the loads prediction, power ramp rate, data mining, wind turbine operation strategy, generator torque, blade pitch1 Abstract--A bi-objective optimization model of power and power changes generated by a wind

  13. Barium Titanate and Bismuth Oxide Nanocomposites Barium titanate, BaTiO3, and bismuth oxide Bi2O3 are transparent materials with

    E-Print Network [OSTI]

    Harmon, Julie P.

    Barium Titanate and Bismuth Oxide Nanocomposites Barium titanate, BaTiO3, and bismuth oxide Bi2O3 that are lead-free. If we cannot shield effectively at nanofiller levels where transparency is maintained, we, Condensed Matter, Vol. 15, 8927 (2003). 21. "Highly Nonlinear Bismuth-Oxide Fiber for Smooth Supercontinuun

  14. A Baseband Ultra-Low Noise SiGe:C BiCMOS 0.25 m Amplifier And Its Application For

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A Baseband Ultra-Low Noise SiGe:C BiCMOS 0.25 µm Amplifier And Its Application For An On-Chip Phase of an ultra-low noise operational amplifier is presented. Its applications are integrated low-frequency noise and ultra low input noise to achieve the required signal to noise ratio. In these instrumentation

  15. Highly tunable electron transport in epitaxial topological insulator (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} thin films

    SciTech Connect (OSTI)

    He Xiaoyue; Guan Tong; Wang Xiuxia; Feng Baojie; Cheng Peng; Chen Lan; Li Yongqing; Wu Kehui [Institute of Physics, Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2012-09-17T23:59:59.000Z

    Atomically smooth, single crystalline (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} films have been grown on SrTiO{sub 3}(111) substrates by molecular beam epitaxy. A full range of Sb-Bi compositions have been studied in order to obtain the lowest possible bulk conductivity. For the samples with optimized Sb compositions (x=0.5{+-}0.1), the carrier type can be tuned from n-type to p-type across the whole thickness with the help of a back-gate. Linear magnetoresistance has been observed at gate voltages close to the maximum in the longitudinal resistance of a (Bi{sub 0.5}Sb{sub 0.5}){sub 2}Te{sub 3} sample. These highly tunable (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} thin films provide an excellent platform to explore the intrinsic transport properties of the three-dimensional topological insulators.

  16. Single-crystalline BiFeO3 nanowires and their ferroelectric behavior Shun Li, Riad Nechache, Catalin Harnagea, Liliya Nikolova, and Federico Rosei

    E-Print Network [OSTI]

    ) Local probing of the interaction between intrinsic defects and ferroelectric domain walls in lithium online 8 November 2012) We report the ferroelectric properties of single-crystalline BiFeO3 nanowires of their unique properties that are often found to be drastically different from their bulk counter- parts,1

  17. Doping dependence of the superconducting gap in Bi2Sr2CaCu2O8 K. C. Hewitt* and J. C. Irwin

    E-Print Network [OSTI]

    Hewitt, Kevin

    Doping dependence of the superconducting gap in Bi2Sr2CaCu2O8ż K. C. Hewitt* and J. C. Irwin.23) were studied to investigate the effects of doping on the symmetry and magnitude of the superconducting). The latter observations have led us to conclude that the doping dependence of the superconducting gap

  18. Novel approaches to low temperature transient liquid phase bonding in the In-Sn/Cu and In-Sn-Bi/Cu systems

    E-Print Network [OSTI]

    Fischer, David S., Ph. D. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    A fluxless low temperature transient liquid phase (LTTLP) bonding process was studied as a method of producing Cu/Cu joints below 125°C and 75°C using interlayer alloys from the In-Sn and In-Sn-Bi systems. Using thermodynamic ...

  19. Synthesis and Characterization of the "Metallic Salts" A5Pn4 (A ) K, Rb, Cs and Pn ) As, Sb, Bi) with Isolated Zigzag Tetramers of Pn4

    E-Print Network [OSTI]

    ) with Isolated Zigzag Tetramers of Pn4 4- and an Extra Delocalized Electron Franck Gascoin and Slavi C. Sevov ) 6.323(1) Ĺ, c ) 12.636(1) Ĺ, ) 122.94(2)°). The compounds contain isolated and flat zigzag tetramers tetramers of Pn4 4-, and also multiple bonding.6 Similar to A3Bi2, they also belong to the class

  20. CORRLATION ANGULAIRE DES NEUTRONS MIS DANS LES RACTIONS 9Be(n, 2n)8Be ET 209Bi(n, 2n)208Bi A 14 MeV

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    .), AECL, 1961, n° 32. RETHMEIER (J.), Thèse, Amsterdam, 1961. RETHMEIER (J.), JONKER (C. C.), RODENBURG (M

  1. Structural and magnetic characterization of BiFe{sub x}Mn{sub 2-x}O{sub 5} oxides (x=0.5, 1.0)

    SciTech Connect (OSTI)

    Retuerto, M., E-mail: retuerto@rci.rutgers.edu [Instituto de Ciencia de Materiales de Madrid, C.S.I.C., Cantoblanco, E-28049 Madrid (Spain); Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road Piscataway, NJ 08854-808 (United States); Martinez-Lope, M.J. [Instituto de Ciencia de Materiales de Madrid, C.S.I.C., Cantoblanco, E-28049 Madrid (Spain); Krezhov, K. [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee Boulevard, Sofia 1784 (Bulgaria); Fernandez-Diaz, M.T. [Institut Laue-Langevin, BP156X, Grenoble F-38042 (France); Alonso, J.A. [Instituto de Ciencia de Materiales de Madrid, C.S.I.C., Cantoblanco, E-28049 Madrid (Spain)

    2011-09-15T23:59:59.000Z

    The title compounds have been synthesized by a citrate technique followed by thermal treatments in air (BiFe{sub 0.5}Mn{sub 1.5}O{sub 5}) or under high oxygen pressure conditions (BiFeMnO{sub 5}), and characterized by X-ray diffraction (XRD), neutron powder diffraction (NPD) and magnetization measurements. The crystal structures have been refined from NPD data in the space group Pbam at 295 K. These phases are isostructural with RMn{sub 2}O{sub 5} oxides (R=rare earths) and contain infinite chains of Mn{sup 4+}O{sub 6} octahedra sharing edges, linked together by (Fe,Mn){sup 3+}O{sub 5} pyramids and BiO{sub 8} units. These units are strongly distorted with respect to those observed in other RFeMnO{sub 5} compounds, due to the presence of the electronic lone pair on Bi{sup 3+}. It is noteworthy the certain level of antisite disorder exhibited in both samples, where the octahedral positions are partially occupied by Fe cations, and vice versa. BiFe{sub x}Mn{sub 2-x}O{sub 5} (x=0.5, 1.0) are short-range magnetically ordered below 20 K for x=0.5 and at 40 K for x=1.0. The main magnetic interactions seem to be antiferromagnetic (AFM); however, the presence of a small hysteresis in the magnetization cycles indicates the presence of some weak ferromagnetic (FM) interactions. - Graphical Abstract: BiFe{sub x}Mn{sub 2-x}O{sub 5} (x=0.5, 1.0) samples are isostructural with BiMn{sub 2}O{sub 5}, belonging to the Pbam space group. The crystal structure contains infinite chains of edge-sharing Mn{sup 4+}O{sub 6} octahedra, interconnected by dimer units of Fe{sup 3+}O{sub 5} square pyramids. These units are strongly distorted due to the presence of the electronic lone pair on Bi{sup 3+}. They are magnetically ordered at low temperatures. The main magnetic interactions seem to be antiferromagnetic with the presence of some weak ferromagnetic response. Highlights: > Two new compounds of formula BiFe{sub x}Mn{sub 2-x}O{sub 5} (x=0.5, 1.0) have been obtained. > Their crystallographic structure is isotypical with that of RMn{sub 2}O{sub 5} materials. > The presence of the electronic lone pair on Bi{sup 3+} severely distorts the crystal structure. > There is no establishment of a long-range ferrimagnetic structure.

  2. Untilting BiFeO{sub 3}: The influence of substrate boundary conditions in ultra-thin BiFeO{sub 3} on SrTiO{sub 3}

    SciTech Connect (OSTI)

    Yang, Yongsoo, E-mail: ysyang@umich.edu; Clarke, Roy [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Schlepütz, Christian M. [X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Adamo, Carolina [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States); Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Schlom, Darrell G. [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States); Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853 (United States)

    2013-11-01T23:59:59.000Z

    We report on the role of oxygen octahedral tilting in the monoclinic-to-tetragonal phase transition in ultra-thin BiFeO{sub 3} films grown on (001) SrTiO{sub 3} substrates. Reciprocal space maps clearly show the disappearance of the integer-order Bragg peak splitting associated with the monoclinic phase when the film thickness decreases below 20 unit cells. This monoclinic-to-tetragonal transition is accompanied by the evolution of the half-order diffraction peaks, which reflects untilting of the oxygen octahedra around the [110] axis, proving that the octahedral tilting is closely correlated with the transition. This structural change is thickness-dependent, and different from a strain-induced transition in the conventional sense.

  3. (Bi, Pb).sub.2, Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.x superconductor and method of making same utilizing sinter-forging

    DOE Patents [OSTI]

    Chen, Nan (Downers Grove, IL); Goretta, Kenneth C. (Downers Grove, IL); Lanagan, Michael T. (Woodridge, IL)

    1998-01-01T23:59:59.000Z

    A (BiPb).sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.x (Bi223) superconductor with high J.sub.c, phase purity, density and mechanical strength is formed from Bi2223 powder which is synthesized from a mixture of Bi.sub.2 O.sub.3, PbO, SrCO.sub.3, CaCo.sub.3 and CuO. The mixture is milled, then dried and calcined to synthesize the Bi2223 powder with the desired phase purity. The calcination is performed by heating the dried mixture for 50 hours at 840.degree. C. The partially synthesized powder is then milled for 1-4 hours before calcining further for another 50 hours at 855.degree. C. to complete the synthesis. After calcination, the Bi2223 powder is cold pressed to a predetermined density and sinter forged under controlled temperature and time to form a Bi2223 superconductor with the desired superconducting properties.

  4. (Bi, Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} superconductor and method of making same utilizing sinter-forging

    DOE Patents [OSTI]

    Chen, N.; Goretta, K.C.; Lanagan, M.T.

    1998-10-13T23:59:59.000Z

    A (BiPb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x}(Bi223) superconductor with high J{sub c}, phase purity, density and mechanical strength is formed from Bi2223 powder which is synthesized from a mixture of Bi{sub 2}O{sub 3}, PbO, SrCO{sub 3}, CaCo{sub 3} and CuO. The mixture is milled, then dried and calcined to synthesize the Bi2223 powder with the desired phase purity. The calcination is performed by heating the dried mixture for 50 hours at 840 C. The partially synthesized powder is then milled for 1--4 hours before calcining further for another 50 hours at 855 C to complete the synthesis. After calcination, the Bi2223 powder is cold pressed to a predetermined density and sinter forged under controlled temperature and time to form a Bi2223 superconductor with the desired superconducting properties. 5 figs.

  5. Combined Charge Carrier Transport and Photoelectrochemical Characterization of BiVO4 Single Crystals: Intrinsic Behavior of a Complex Metal Oxide

    SciTech Connect (OSTI)

    Rettie, Alexander J.; Lee, Heung Chan; Marshall, Luke G.; Lin, Jung-Fu; Capen, Cigdem; Lindemuth, Jeffrey; McCloy, John S.; Zhou, Jianshi; Bard, Allen J.; Mullins, C. Buddie

    2013-07-08T23:59:59.000Z

    ABSTRACT: Bismuth vanadate (BiVO4) is a promising photoelectrode material for the oxidation of water, but fundamental studies of this material are lacking. To address this, we report electrical and photoelectrochemical (PEC) properties of BiVO4 single crystals (undoped, 0.6% Mo and 0.3% W:BiVO4) grown using the floating zone technique. We demonstrate that a small polaron hopping conduction mechanism dominates from 250-400 K, transitioning to a variable range hopping mechanism at lower temperatures. An anisotropy ratio of ~3 was observed along the c-axis, attributed to the layered structure of BiVO4. Measurements of the AC field Hall effect yielded an electron mobility of ~0.2 cm2 V-1 s-1 for Mo and W:BiVO4 at 300 K. By application of the Gärtner model, a hole diffusion length of ~140 nm was estimated. As a result of low carrier mobility, attempts to measure the DC Hall effect were unsuccessful. Analyses of the Raman spectra showed that Mo and W substituted for V and acted as donor impurities. Mott-Schottky analysis of electrodes with the (001) face exposed yielded a flat band potential of 0.03-0.08 V vs. RHE, while incident photon conversion efficiency tests showed that the dark coloration of the doped single crystals did not result in additional photocurrent. Comparison of these intrinsic properties to other metal oxides for PEC applications gives valuable insight into this material as a photoanode.

  6. Thermoelectric properties of indium doped PbTe{sub 1-y}Se{sub y} alloys

    SciTech Connect (OSTI)

    Bali, Ashoka; Mallik, Ramesh Chandra, E-mail: rcmallik@physics.iisc.ernet.in [Thermoelectric Materials and Devices Laboratory, Department of Physics, Indian Institute of Science, Bangalore 560012, Karnataka (India); Wang, Heng; Snyder, G. Jeffrey [Department of Materials Science, California Institute of Technology, Pasadena, California 91125 (United States)

    2014-07-21T23:59:59.000Z

    Lead telluride and its alloys are well known for their thermoelectric applications. Here, a systematic study of PbTe{sub 1-y}Se{sub y} alloys doped with indium has been done. The powder X-Ray diffraction combined with Rietveld analysis confirmed the polycrystalline single phase nature of the samples, while microstructural analysis with scanning electron microscope results showed densification of samples and presence of micrometer sized particles. The temperature dependent transport properties showed that in these alloys, indium neither pinned the Fermi level as it does in PbTe, nor acted as a resonant dopant as in SnTe. At high temperatures, bipolar effect was observed which restricted the zT to 0.66 at 800?K for the sample with 30% Se content.

  7. Algorithmically scalable block preconditioner for fully implicit shallow water equations in CAM-SE

    SciTech Connect (OSTI)

    Lott, P Aaron [Lawrence Livermore National Laboratory (LLNL); Woodward, Carol [Lawrence Livermore National Laboratory (LLNL); Evans, Katherine J [ORNL

    2015-01-01T23:59:59.000Z

    Performing accurate and efficient numerical simulation of global atmospheric climate models is challenging due to the disparate length and time scales over which physical processes interact. Implicit solvers enable the physical system to be integrated with a time step commensurate with processes being studied. The dominant cost of an implicit time step is the ancillary linear system solves, so we have developed a preconditioner aimed at improving the efficiency of these linear system solves. Our preconditioner is based on an approximate block factorization of the linearized shallow-water equations and has been implemented within the spectral element dynamical core within the Community Atmospheric Model (CAM-SE). In this paper we discuss the development and scalability of the preconditioner for a suite of test cases with the implicit shallow-water solver within CAM-SE.

  8. CdS/PbSe heterojunction for high temperature mid-infrared photovoltaic detector applications

    SciTech Connect (OSTI)

    Weng, Binbin, E-mail: binbinweng@ou.edu, E-mail: shi@ou.edu; Qiu, Jijun; Zhao, Lihua; Chang, Caleb [The School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Shi, Zhisheng, E-mail: binbinweng@ou.edu, E-mail: shi@ou.edu [The School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Nanolight, Inc., Norman, Oklahoma 73069 (United States)

    2014-03-24T23:59:59.000Z

    n-CdS/p-PbSe heterojunction is investigated. A thin CdS film is deposited by chemical bath deposition on top of epitaxial PbSe film by molecular beam epitaxy on Silicon. Current-voltage measurements demonstrate very good junction characteristics with rectifying ratio of ?178 and ideality factor of 1.79 at 300?K. Detectors made with such structure exhibit mid-infrared spectral photoresponse at room temperature. The peak responsivity R{sub ?} and specific detectivity D{sup *} are 0.055?A/W and 5.482?×?10{sup 8}?cm·Hz{sup 1/2}/W at ??=?4.7??m under zero-bias photovoltaic mode. Temperature-dependent photoresponse measurements show abnormal intensity variation below ?200?K. Possible reasons for this phenomenon are also discussed.

  9. Optical nonlinear absorption characteristics of Sb{sub 2}Se{sub 3} nanoparticles

    SciTech Connect (OSTI)

    Muralikrishna, Molli, E-mail: muralikrishnamolli@sssihl.edu.in; Kiran, Aditha Sai, E-mail: muralikrishnamolli@sssihl.edu.in; Ravikanth, B., E-mail: muralikrishnamolli@sssihl.edu.in; Sowmendran, P., E-mail: muralikrishnamolli@sssihl.edu.in; Muthukumar, V. Sai, E-mail: muralikrishnamolli@sssihl.edu.in; Venkataramaniah, Kamisetti, E-mail: muralikrishnamolli@sssihl.edu.in [Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam-515 134 (India)

    2014-04-24T23:59:59.000Z

    In this work, we report for the first time, the nonlinear optical absorption properties of antimony selenide (Sb{sub 2}Se{sub 3}) nanoparticles synthesized through solvothermal route. X-ray diffraction results revealed the crystalline nature of the nanoparticles. Electron microscopy studies revealed that the nanoparticles are in the range of 10 - 40 nm. Elemental analysis was performed using EDAX. By employing open aperture z-scan technique, we have evaluated the effective two-photon absorption coefficient of Sb{sub 2}Se{sub 3} nanoparticles to be 5e-10 m/W at 532 nm. These nanoparticles exhibit strong intensity dependent nonlinear optical absorption and hence could be considered to have optical power limiting applications in the visible range.

  10. Magnetism in La?O?(Fe??xMnx)?Se? tuned by Fe/Mn ratio

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

    Lei, Hechang; Bozin, Emil S.; Llobet, A.; Ivanovski, V.; Koteski, V.; Belosevic-Cavor, J.; Cekic, B.; Petrovic, C.

    2012-09-01T23:59:59.000Z

    We report the evolution of structural and magnetic properties in La?O?(Fe??xMnx)?Se?. Heat capacity and bulk magnetization indicate an increased ferromagnetic component of the long-range magnetic order and possible increased degree of frustration. Atomic disorder on Fe(Mn) sites suppresses the temperature of the long-range order whereas intermediate alloys show a rich magnetic phase diagram.

  11. A inevitabilidade de um sismo em Lisboa, s no se sabendo

    E-Print Network [OSTI]

    Instituto de Sistemas e Robotica

    ALTO RISCO SÍSMICO EM LISBOA · A inevitabilidade de um sismo em Lisboa, só não se sabendo a data.balasteiro@sol.pt O SOL fez uma ronda pela capital, acompanhado por especialistas: em caso de sismo, muitos hospitais prô- i ximo sismo de gran- I des dimensões em I Lisboa - uma certe- z a científica, segun- do os

  12. High-Temperature Order/Disorder Transition in the Thermoelectric Cu3SbSe3

    SciTech Connect (OSTI)

    Kirkham, Melanie J [ORNL; Majsztrik, Paul W [ORNL; Skoug, Eric [Michigan State University, East Lansing; Morelli, Donald [Michigan State University, East Lansing; Wang, Hsin [ORNL; Porter, Wallace D [ORNL; Payzant, E Andrew [ORNL; Lara-Curzio, Edgar [ORNL

    2011-01-01T23:59:59.000Z

    We report the results from an investigation into the structural evolution of a potential new thermoelectric material, Cu3SbSe3, as a function of temperature from 25 to 390 C. From high-temperature X-ray diffraction data, the refined lattice parameters were seen to change non-linearly, but continuously, with temperature, with an increased rate of thermal expansion in the a and b lattice parameters from around 125 C until around 175 C and negative thermal expansion in the c axis from around 100 C until around 175 C. Crystallographic charge flipping analysis indicated an increase in the disorder of the copper cations with temperature. This reversible order/disorder phase transition in Cu3SbSe3 affects the transport properties, as evidenced by thermal diffusivity measurements, which change from negative to positive slope at the transition temperature. This structural change in Cu3SbSe3 has implications for its potential use in thermoelectric generators.

  13. Enhanced ferroelectric properties and thermal stability of nonstoichiometric 0.92(Na{sub 0.5}Bi{sub 0.5})TiO{sub 3}-0.08(K{sub 0.5}Bi{sub 0.5})TiO{sub 3} single crystals

    SciTech Connect (OSTI)

    Zhang, Haiwu, E-mail: zhw3789@sina.com, E-mail: hsluo@mail.sic.ac.cn; Chen, Chao; Deng, Hao; Li, Long [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800 (China) [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Zhao, Xiangyong; Lin, Di; Li, Xiaobing; Ren, Bo; Luo, Haosu, E-mail: zhw3789@sina.com, E-mail: hsluo@mail.sic.ac.cn [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800 (China)] [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800 (China); Yan, Jun [Shibei Power Supply Branch, Shanghai Municipal Electric Power Company, Shanghai 200072 (China)] [Shibei Power Supply Branch, Shanghai Municipal Electric Power Company, Shanghai 200072 (China)

    2013-11-18T23:59:59.000Z

    Bi deficient, Mn doped 0.92(Na{sub 0.5}Bi{sub 0.5})TiO{sub 3}-0.08(K{sub 0.5}Bi{sub 0.5})TiO{sub 3} single crystals were grown by carefully controlled top-seeded solution growth method. Local structures were investigated by transmission electron microscopy. The site occupation and valence state of manganese were characterized by electron paramagnetic resonance spectrum. The leakage current density in the as-grown single crystals is effectively depressed. The introduced defect complexes suppress the temperature induced phase transformation, increasing the depolarization temperature (165?°C) and thermal stability of ferroelectric properties.

  14. Reduced leakage in epitaxial BiFeO{sub 3} films following oxygen radio frequency plasma treatment

    SciTech Connect (OSTI)

    Kothari, Deepti [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India) [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India); UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452 017 (India); Upadhyay, Sanjay K.; Raghavendra Reddy, V. [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452 017 (India)] [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452 017 (India); Jariwala, C.; Raole, P. M. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)] [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2013-06-07T23:59:59.000Z

    Epitaxial BiFeO{sub 3} (BFO) films were deposited using pulsed laser deposition method. The prepared films were characterized using x-ray diffraction, x-ray reflectivity, ferroelectric loop tracer, and leakage current measurements before and after oxygen plasma treatment. The leakage current of the films, a crucial parameter in device applications, is observed to be reduced by two orders of magnitude with oxygen plasma treatment at room temperature. P-E hysteresis loops were observed in oxygen plasma treated BFO films. The observed results indicate the usefulness of oxygen radio frequency plasma treatment (RF 13.56 MHz), which is an effective and low temperature processing technique, in such lossy ferroelectric thin films.

  15. Five-dimensional visualization of phase transition in BiNiO{sub 3} under high pressure

    SciTech Connect (OSTI)

    Liu, Yijin, E-mail: liuyijin@slac.stanford.edu, E-mail: wyang@ciw.edu [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Wang, Junyue; Yang, Wenge, E-mail: liuyijin@slac.stanford.edu, E-mail: wyang@ciw.edu [Center of High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203 (China); High Pressure Synergetic Consortium, Geophysical Laboratory, Carnegie Institution of Washington, 9700 S Cass Avenue, Argonne, Illinois 60439 (United States); Azuma, Masaki [Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama 226-8503 (Japan); Mao, Wendy L. [Geological and Environmental Sciences, 450 Serra Mall, Stanford University, Stanford, California 94305 (United States); SLAC National Accelerator Laboratory, Stanford Institute for Materials and Energy Sciences, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Photon Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States)

    2014-01-27T23:59:59.000Z

    Colossal negative thermal expansion was recently discovered in BiNiO{sub 3} associated with a low density to high density phase transition under high pressure. The varying proportion of co-existing phases plays a key role in the macroscopic behavior of this material. Here, we utilize a recently developed X-ray Absorption Near Edge Spectroscopy Tomography method and resolve the mixture of high/low pressure phases as a function of pressure at tens of nanometer resolution taking advantage of the charge transfer during the transition. This five-dimensional (X, Y, Z, energy, and pressure) visualization of the phase boundary provides a high resolution method to study the interface dynamics of high/low pressure phase.

  16. The Use of Oxygen Gradients as a Texturing Mechanism During Isothermal Melt Processing of Bi-2212 Superconductors

    SciTech Connect (OSTI)

    Holesinger, T.G.; Hults, W.L.; Smith, J.L. [Los Alamos National Lab., NM (United States); Dai, Weiming; Marken, K.R. [Oxford Instruments Inc., Carteret, NJ (United States)

    1997-01-01T23:59:59.000Z

    Isothermal melt processing has been used to produce high critical currents (I{sub c}`s) and current densities (J{sub c}`s) in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y} round wires and flat tapes. I{sub c}`s and J{sub c}`s of 225 A and 80 kA/cm{sup 2} have been obtained in short length, monocore wires. However, voids and other macroscopic defects have limited performance over longer lengths. Isothermally melt processed tapes have yielded I{sub c} and J{sub c} values up to 341 A and 245 kA/cm{sup 2}, although performance over longer lengths is somewhat reduced. A test coil made from 0.5 m of tape yielded, I{sub c} and J{sub c} values of 208 A and 153 kA/cm{sup 2}, respectively.

  17. Lightweight PV Inverters: Dual Bi-Directional IGBTs Modules Enables Breakthrough PV Inverter Using Current Modulation Topology

    SciTech Connect (OSTI)

    None

    2012-01-30T23:59:59.000Z

    Solar ADEPT Project: PV inverters convert DC power generated by modules into usable AC power. IPC’s initial 30kW 94lb. PV inverter reduces the weight of comparable 30kW PV inverters by 90%—reducing the cost of materials, manufacturing, shipping, and installation. With ARPA-E support, new bi-directional silicon power switches will be developed, commercialized, and utilized in IPC’s next-generation PV inverter. With these components, IPC will produce 100kW inverters that weight less than 100lb., reducing the weight of conventional 3,000lb. 100kW inverters by more than 95%. The new power switches will cut IPC’s $/W manufacturing cost in half, as well as further reduce indirect shipping and installation costs.

  18. Preliminary safety analysis of Pb-Bi cooled 800 MWt modified CANDLE burn-up scheme based fast reactors

    SciTech Connect (OSTI)

    Su'ud, Zaki, E-mail: szaki@fi.itba.c.id [Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Science, Bandung Institute of Technology (Ganesha 10 Bandung, Indonesia) (Indonesia); Sekimoto, H., E-mail: hsekimot@gmail.com [Research Lab. For Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo (Japan)

    2014-09-30T23:59:59.000Z

    Pb-Bi Cooled fast reactors with modified CANDLE burn-up scheme with 10 regions and 10 years cycle length has been investigated from neutronic aspects. In this study the safety aspect of such reactors have been investigated and discussed. Several condition of unprotected loss of flow (ULOF) and unprotected rod run-out transient over power (UTOP) have been simulated and the results show that the reactors excellent safety performance. At 80 seconds after unprotected loss of flow condition, the core flow rate drop to about 25% of its initial flow and slowly move toward its natural circulation level. The maximum fuel temperature can be managed below 1000°C and the maximum cladding temperature can be managed below 700°C. The dominant reactivity feedback is radial core expansion and Doppler effect, followed by coolant density effect and fuel axial expansion effect.

  19. Low-Power Circuits for a 2.5-V, 10.7-to-86-Gb/s Serial Transmitter in 130-nm SiGe BiCMOS

    E-Print Network [OSTI]

    Voinigescu, Sorin Petre

    Low-Power Circuits for a 2.5-V, 10.7-to-86-Gb/s Serial Transmitter in 130-nm SiGe BiCMOS Timothy O operating up to 86 Gb/s are designed and implemented in a 130-nm SiGe BiCMOS technology with 150-GHz fT SiGe-GHz fT SiGe BiCMOS technology. Operation is verified up to 86 Gb/s at room temperature (92Gb/s and 71

  20. The thermally stimulated conductivity in amorphous thin film As?Se?

    E-Print Network [OSTI]

    Bryant, John Duffie

    1972-01-01T23:59:59.000Z

    V with a 14 -3 density of 9. 73 x 10 cm . The thermal velocity of the carriers 6 -18 was 6. 34 x 10 cm/sec, and the capture cross section was 2. 7 x 10 2 cm . These results indicate that the Nett-Davis model is more ap- plicable to amorphous As Se... II-3 Sample Holder Design (not to scale) 15 16 17 11-4 Output Curve for Chromel-Constantan Thermo- couple (Voltage vs. Temperature) (ref. 29) 19 II-5 System Cooling Curve (Temperature vs. Time) 20 II-6 System Heating Curve for a Constant Heater...

  1. Ann bay lodyans 10 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 10 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvčl : Fondasyon Alfa Lwčs, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml Tl CHENN LO A Te gen yon nonm ki te...

  2. Network Rigidity in GeSe2 Glass at High Pressure

    SciTech Connect (OSTI)

    Antao,S.; Benmore , C.; Li, B.; Wang, L.; Bychkov, E.; Parise, J.

    2008-01-01T23:59:59.000Z

    Acoustic measurements using synchrotron radiation have been performed on glassy GeSe2 up to pressures of 9.6 GPa. A minimum observed in the shear-wave velocity, associated anomalous behavior in Poisson's ratio, and discontinuities in elastic moduli at 4 GPa are indicative of a gradual structural transition in the glass. This is attributed to a network rigidity minimum originating from a competition between two densification mechanisms. At pressures up to 3 GPa, a conversion from edge- to corner-sharing tetrahedra results in a more flexible network. This is contrasted by a gradual increase in coordination number with pressure, which leads to an overall stiffening of the glass.

  3. Giant increase in critical current density of KxFe2-ySe? single crystals

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

    Lei, Hechang; Petrovic, C.

    2011-12-01T23:59:59.000Z

    The critical current density Jabc of KxFe2-ySe? single crystals can be enhanced by more than one order of magnitude, up to ~2.1×10? A/cm˛ by the post annealing and quenching technique. A scaling analysis reveals the universal behavior of the normalized pinning force as a function of the reduced field for all temperatures, indicating the presence of a single vortex pinning mechanism. The main pinning sources are three-dimensional (3D) point-like normal cores. The dominant vortex interaction with pinning centers is via spatial variations in critical temperature Tc (“?Tc pinning”).

  4. The thermally stimulated conductivity in amorphous thin film As?Se

    E-Print Network [OSTI]

    Bryant, John Duffie

    1972-01-01T23:59:59.000Z

    V with a 14 -3 density of 9. 73 x 10 cm . The thermal velocity of the carriers 6 -18 was 6. 34 x 10 cm/sec, and the capture cross section was 2. 7 x 10 2 cm . These results indicate that the Nett-Davis model is more ap- plicable to amorphous As Se... II-3 Sample Holder Design (not to scale) 15 16 17 11-4 Output Curve for Chromel-Constantan Thermo- couple (Voltage vs. Temperature) (ref. 29) 19 II-5 System Cooling Curve (Temperature vs. Time) 20 II-6 System Heating Curve for a Constant Heater...

  5. Nanosecond switching in GeSe phase change memory films by atomic force microscopy

    SciTech Connect (OSTI)

    Bosse, James L.; Huey, Bryan D., E-mail: bhuey@ims.uconn.edu [Department of Materials Science and Engineering, 97 North Eagleville Road, Unit 3136, Storrs, Connecticut 06269-3136 (United States); Grishin, Ilya; Kolosov, Oleg V. [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom); Gyu Choi, Yong [Department of Materials Science and Engineering, Korea Aerospace University, Goyang-si, Gyeonggi-do, 412-791 (Korea, Republic of); Cheong, Byung-ki; Lee, Suyoun [Electronic Materials Research Center, Korea Institute of Science and Technology, Seongbuk-gu, Seoul 136-791 (Korea, Republic of)

    2014-02-03T23:59:59.000Z

    Nanosecond scale threshold switching is investigated with conducting atomic force microscopy (AFM) for an amorphous GeSe film. Switched bits exhibit 2–3 orders of magnitude variations in conductivity, as demonstrated in phase change based memory devices. Through the nm-scale AFM probe, this crystallization was achieved with pulse durations of as low as 15?ns, the fastest reported with scanning probe based methods. Conductance AFM imaging of the switched bits further reveals correlations between the switched volume, pulse amplitude, and pulse duration. The influence of film heterogeneities on switching is also directly detected, which is of tremendous importance for optimal device performance.

  6. Ann bay lodyans 7 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01T23:59:59.000Z

    ("Tonton Liben") ki pare ti liv sa a. AYITI SE PEP AYISYEN PM 7854 .H39 A56 Enstiti Etid Ayisyen - Inivesite Kannzas Bon Nouvel Fondasyon Alfa Lwes 1997 MALIS AP VANN, WA AP PRAN Yon jou yon neg t ap fe yon ti vizit lakay Malis. Pandan li t ap... I ak nan lespri I, ti lanp sa a ap pemet li we sot isit rive nan Ginen, menm anndan yon kay ki femen ak mi." Neg la mande: "Eske ou te seye sa deja?" Malis reponn: "O non, monche! Eske ou kwe m ta ka rete konsa jis pou m ka fe jouda, fouye lavi...

  7. Neutron Scattering Study on spin dynamics in superconducting (TlRb)2Fe4Se5

    SciTech Connect (OSTI)

    Chi, Songxue [ORNL; Ye, Feng [ORNL; Bao, Wei [Renmin University of China; Fang, Dr. Minghu [Zhejiang University; Wang, H.D. [Zhejiang University; Dong, C.H. [Zhejiang University; Savici, Andrei T [ORNL; Granroth, Garrett E [ORNL; Stone, Matthew B [ORNL; Fishman, Randy Scott [ORNL

    2013-01-01T23:59:59.000Z

    Spin dynamics in superconducting (Tl,Rb)2Fe4Se5 was investigated using the inelastic neutron scattering technique. Spin wave branches that span an energy range from 6.5 to 209 meV are success- fully described by a Heisenberg model whose dominant interactions include only the in-plane nearest (J1 and J0 1) and next nearest neighbor (J2 and J0 2) exchange terms within and between the tetramer spin blocks, respectively. These exchange constants, experimentally determined in this work, would crucially constrain the diverse theoretical viewpoints on magnetism and superconductivity in the Fe-based materials.

  8. PHaSE | U.S. DOE Office of Science (SC)

    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 Science (SC)IntegratedSpeeding access toTest andOptimize832 2.860SelectedGLOWAGREEMENTPHaSE Energy

  9. DISSERTATION IMPACT OF SECONDARY BARRIERS ON CuIn1-xGaxSe2 SOLAR-CELL

    E-Print Network [OSTI]

    Sites, James R.

    DISSERTATION IMPACT OF SECONDARY BARRIERS ON CuIn1-xGaxSe2 SOLAR-CELL OPERATION Submitted by Alexei Impact of Secondary Barriers on CuIn1-xGaxSe2 Solar-Cell Operation Thin-film solar cells based on CuInSe2 layers in p-n junctions of CIGS solar cells often improve photodiode properties of the devices. Several

  10. Investigation of polycrystalline thin-film CuInSe{sub 2} solar cells based on ZnSe windows. Annual subcontract report, 15 Febraury 1992--14 February 1993

    SciTech Connect (OSTI)

    Olsen, L C [Washington State Univ. at Tri-Cities, Richland, WA (United States)

    1994-05-01T23:59:59.000Z

    Investigations of ZnSe/CIS solar cells are being carried out in an effort to improve the efficiencies CIS cells and to determine if ZnSe is a viable alternative to CdS as a window material. MOCVD growth of ZnSe is accomplished in a SPIRE 500XT reactor housed in the Electronic Materials Laboratory at WSU Tri-Cities by reacting a zinc adduct with H{sub 2}Se. Conductive n-type ZnSe is grown by using iodine as a dopant. Ethyliodide was mixed with helium and installed on one of the gas lines to the system. ZnSe films have been grown on CIS substrates at 200{degrees}C to 250{degrees}C. ZnO is also being deposited by MOCVD by reacting tetrahydrofuran (THF) with a zinc adduct. ZnSe/CIS heterojunctions have been studied by growing n-ZnSe films onto 2 cm x 2 cm CIS substrates diced from materials supplied by Siemens and then depositing an array of aluminum circular areas 2.8.mm in diameter on top of the ZnSe to serve as contacts. Al films are deposited with a thickness of 80 to l00 {angstrom}so that light can pass through the film, thus allowing the illuminated characteristics of the ZnSe/CIS junction to be tested. Accounting for the 20 to 25 % transmittance through the Al film into the ZnSe/CIS structure, current devices have estimated, active-area AM1.5 efficiencies of 14 %. Open circuit voltages > 500 mV are often attained.

  11. Characterization and device performance of (AgCu)(InGa)Se2 absorber layers

    SciTech Connect (OSTI)

    Hanket, Gregory; Boyle, Jonathan H.; Shafarman, William N.

    2009-06-08T23:59:59.000Z

    The study of (AgCu)(InGa)Se2 absorber layers is of interest in that Ag-chalcopyrites exhibit both wider bandgaps and lower melting points than their Cu counterparts. (AgCu)(InGa)Se2 absorber layers were deposited over the composition range 0 < Ag/(Ag+Cu) < 1 and 0.3 < Ga/(In+Ga) < 1.0 using a variety of elemental co-evaporation processes. Films were found to be singlephase over the entire composition range, in contrast to prior studies. Devices with Ga content 0.3 < Ga/(In+Ga) <0.5 tolerated Ag incorporation up to Ag/(Ag+Cu) = 0.5 without appreciable performance loss. Ag-containing films with Ga/(In+Ga) = 0.8 showed improved device characteristics over Cu-only control samples, in particular a 30-40% increase in short-circuit current. An absorber layer with composition Ag/(Ag+Cu) = 0.75 and Ga/(In+Ga) = 0.8 yielded a device with VOC = 890 mV, JSC = 20.5mA/cm2, fill factor = 71.3%, and ? = 13.0%.

  12. Effect of Ligands on Characteristics of (CdSe)13 Quantum Dot

    SciTech Connect (OSTI)

    Gao, Yang; Zhou, Bo; Kang, Seung-gu; Xin, Minsi; Yang, Ping; Dai, Xing; Wang, Zhigang; Zhou, Ruhong

    2014-01-01T23:59:59.000Z

    The widespread applications of quantum dots (QDs) have spurred an increasing interest in the study of their coating ligands, which can not only protect the electronic structures of the central QDs, but also control their permeability through biological membranes with both size and shape. In this work, we have used density functional theory (DFT) to investigate the electronic structures of (CdSe)13 passivated by OPMe2(CH2)nMe ligands with different lengths and various numbers of branches (Me=methyl group, n = 0, 1-3). Our results show that the absorption peak in the ultraviolet-visible (UV-vis) spectra displays a clear blue-shift, on the scale of ~100 nm, upon the binding of ligands. Once the total number of ligands bound with (CdSe)13 reached a saturated number (9 or 10), no more blue-shift occurred in the absorption peak in the UV-vis spectra. On the other hand, the aliphatic chain length of ligands has a negligible effect on the optical properties of the QD core. Analyses of the bonding characteristics confirm that optical transitions are dominantly governed by the central QD core rather than the organic passivation. Interestingly, the density of states (DOS) share similar characteristics as vibrational spectra, even though there is no coordination vibration mode between the ligands and the central QD. These findings might provide insights on the material design for the passivation of quantum dots for biomedical applications.

  13. The role of ligands in the optical and electronic spectra of CdSe nanoclusters

    SciTech Connect (OSTI)

    Kilina, Svletana [Los Alamos National Laboratory; Sergei, Ivanov A [Los Alamos National Laboratory; Victor, Klimov I [Los Alamos National Laboratory; Sergei, Tretiak [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    We investigate the impact of ligands on morphology, electronic structure, and optical response of the Cd33Se33 cluster, which already overlapps in size with the smallest synthesized CdSe quantum dots (QDs). Our Density Functional Theory (DFT) calculations demonstrate significant surface reorganization both for the bare cluster and for the cluster capped by amine and phosphine oxide ligand models. We observe strong surface-ligand interactions leading to substantial charge redistribution and polarization effects on the surface. This effect results in the appearance of hybridized states, where the electronic density is spread over the cluster and the ligands. Neither the ligand's nor hybridized molecular orbitals appear as trap states inside or near the band gap of the QD. Instead, being optically dark, dense hybridized states from the edges of the valence and the conduction bands could open new relaxation channels for high energy photoexcitations. Comparing quantum dots passivated by different ligands, we found that hybridized states are denser in at the edge of the conduction band of the cluster ligated with phosphine oxide molecules than that with primary amines. Such a different manifestation of ligand binding may potentially lead to the faster electron relaxation in dots passivated by phosphine oxide than by amine ligands, which is in agreement with experimental data.

  14. Structure determination of the high-pressure phase of CdSe

    SciTech Connect (OSTI)

    Li, Yanchun, E-mail: liyc@ihep.ac.cn, E-mail: liuj@ihep.ac.cn; Lin, Chuanlong; Li, Xiaodong; Liu, Jing, E-mail: liyc@ihep.ac.cn, E-mail: liuj@ihep.ac.cn [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Science, 100049 Beijing (China); Li, Gong [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Xu, Jian [Institute of Fluid Physics, China Academy of Engineering Physics, P. O. Box 919-102, Mianyang, Sichuan 621900 (China)

    2014-06-14T23:59:59.000Z

    Structural phase transition sequence of CdSe has been investigated at pressures up to 60?GPa under quasi-hydrostatic conditions using synchrotron X-ray diffraction. A phase transition from the wurtzite type (B4) to the NaCl-type (B1) structure has been observed, followed by another phase transition to an orthorhombic structure at 27?GPa, in agreement with previous reports. We show that this high-pressure orthorhombic phase has a Pnma symmetry rather than being a Cmcm-symmetric structure as previously suggested. From our observations, the appearance of the new reflections and reflection splitting with increasing pressure is due to the change of atomic relative positions in crystal lattice and the difference in the compression ratio of lattice parameters for the Pnma structure, and we find no evidence for the third phase transition reported previously. The pressure-induced phase transition of CdSe has been further confirmed by the density-functional theory calculations.

  15. Polytypism, polymorphism, and superconductivity in TaSe2-xTex

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

    Luo, Huixia; Tao, Jing; Xie, Weiwei; Inoue, Hiroyuki; Gyenis, Andras; Krizan, Jason W.; Yazdani, Ali; Zhu, Yimei; Cava, R. J.

    2015-03-17T23:59:59.000Z

    Polymorphism in materials often leads to significantly different physical properties - the rutile and anatase polymorphs of TiO? are a prime example. Polytypism is a special type of polymorphism, occurring in layered materials when the geometry of a repeating structural layer is maintained but the layer stacking sequence of the overall crystal structure can be varied; SiC is an example of a material with many polytypes. Although polymorphs can have radically different physical properties, it is much rarer for polytypism to impact physical properties in a dramatic fashion. Here we study the effects of polytypism and polymorphism on the superconductivitymore »of TaSe?, one of the archetypal members of the large family of layered dichalcogenides. We show that it is possible to access 2 stable polytypes and 2 stable polymorphs in the TaSe2-xTex solid solution, and find that the 3R polytype shows a superconducting transition temperature that is between 6 and 17 times higher than that of the much more commonly found 2H polytype. The reason for this dramatic change is not apparent, but we propose that it arises either from a remarkable dependence of Tc on subtle differences in the characteristics of the single layers present, or from a surprising effect of the layer stacking sequence on electronic properties that instead are expected to be dominated by the properties of a single layer in materials of this kind.« less

  16. SeZnSb alloy and its nano tubes, graphene composites properties

    SciTech Connect (OSTI)

    Singh, Abhay Kumar [Department of Physics, Indian Institute of Physics, Bangalore-560012 (India)

    2013-04-15T23:59:59.000Z

    Composite can alter the individual element physical property, could be useful to define the specific use of the material. Therefore, work demonstrates the synthesis of a new composition Se{sub 96}-Zn{sub 2}-Sb{sub 2} and its composites with 0.05% multi-walled carbon nano tubes and 0.05% bilayer graphene, in the glassy form. The diffused amorphous structure of the multi walled carbon nano tubes and bilayer gaphene in the Se{sub 96}-Zn{sub 2}-Sb{sub 2} alloy have been analyzed by using the Raman, X-ray photoluminescence spectroscopy, Furrier transmission infrared spectra, photoluminescence, UV/visible absorption spectroscopic measurements. The diffused prime Raman bands (G and D) have been appeared for the multi walled carbon nano tubes and graphene composites, while the X-ray photoluminescence core energy levels peak shifts have been observed for the composite materials. Subsequently the photoluminescence property at room temperature and a drastic enhancement (upto 80%) in infrared transmission percentage has been obtained for the bilayer graphene composite, along with optical energy band gaps for these materials have been evaluated 1.37, 1.39 and 1.41 eV.

  17. Effects of K doping on structural and superconducting properties of Bi{sub 1.5}Pb{sub 0.5}Sr{sub 1.8}CaCu{sub 2}O{sub 8+?} compounds

    SciTech Connect (OSTI)

    Belala, K; Mosbah, M. F. [Material Sciences and Applications Research Unit, Physics Department, Constantine 1 University, B.P. 325 Route d'Ain El Bey, 25017 Constantine (Algeria)

    2013-12-16T23:59:59.000Z

    Two kinds of potassium doped Bi(Pb)2212 samples are used to investigate the effect of doping the Bi(Pb)2212 ((Bi,Pb){sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8}) phase by potassium (K): In the first one K is substituted on the Sr site; In the second one K is added. Using the solid state method reaction samples of Bi{sub 1.5}Pb{sub 0.5}(Sr{sub 1.8?x}K{sub x})CaCu{sub 2}O{sub 8+d} and Bi{sub 1.5}Pb{sub 0.5}Sr{sub 1.8}CaCu{sub 2}O{sub 8+d}K{sub x} (0 ? x? 0.05) have been prepared from powders of carbonates and primary oxides having purity over 99%. The samples have been characterized by X ray diffraction (XRD), scanning electron microscopy (SEM) and resistivity versus temperature measurements. Results show how the kind and the rate of doping by potassium affects the structural and transport properties of Bi(Pb)2212 phase.

  18. Atomic layer deposition of bismuth oxide using Bi(OCMe{sub 2}{sup i}Pr){sub 3} and H{sub 2}O

    SciTech Connect (OSTI)

    Austin, Dustin Z., E-mail: austind@eecs.oregonstate.edu; Conley, John F., E-mail: jconley@eecs.oregonstate.edu [Department of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331 (United States); Allman, Derryl; Price, David; Hose, Sallie [ON Semiconductor, Technology Development, Gresham, Oregon 97030 (United States); Saly, Mark [SAFC Hitech, Haverhill, Massachusetts 01832 (United States)

    2014-01-15T23:59:59.000Z

    Bismuth oxide thin films were deposited by atomic layer deposition using Bi(OCMe{sub 2}{sup i}Pr){sub 3} and H{sub 2}O at deposition temperatures between 90 and 270?°C on Si{sub 3}N{sub 4}, TaN, and TiN substrates. Films were analyzed using spectroscopic ellipsometry, x-ray diffraction, x-ray reflectivity, high-resolution transmission electron microscopy, and Rutherford backscattering spectrometry. Bi{sub 2}O{sub 3} films deposited at 150?°C have a linear growth per cycle of 0.039?nm/cycle, density of 8.3?g/cm{sup 3}, band gap of approximately 2.9?eV, low carbon content, and show the ? phase structure with a (201) preferred crystal orientation. Deposition temperatures above 210?°C and postdeposition anneals caused uneven volumetric expansion, resulting in a decrease in film density, increased interfacial roughness, and degraded optical properties.

  19. Calculations of Branching Ratios for Radiative-Capture, One-Proton, and Two-Neutron Channels in the Fusion Reaction $^{209}$Bi+$^{70}$Zn

    E-Print Network [OSTI]

    Ichikawa, Takatoshi; 10.1143/JPSJ.79.074201

    2010-01-01T23:59:59.000Z

    We discuss the possibility of the non-one-neutron emission channels in the cold fusion reaction $^{70}$Zn + $^{209}$Bi to produce the element Z=113. For this purpose, we calculate the evaporation-residue cross sections of one-proton, radiative-capture, and two-neutron emissions relative to the one-neutron emission in the reaction $^{70}$Zn + $^{209}$Bi. To estimate the upper bounds of those quantities, we vary model parameters in the calculations, such as the level-density parameter and the height of the fission barrier. We conclude that the highest possibility is for the 2n reaction channel, and its upper bounds are 2.4$%$ and at most less than 7.9% with unrealistic parameter values, under the actual experimental conditions of [J. Phys. Soc. Jpn. {\\bf 73} (2004) 2593].

  20. Calculations of Branching Ratios for Radiative-Capture, One-Proton, and Two-Neutron Channels in the Fusion Reaction $^{209}$Bi+$^{70}$Zn

    E-Print Network [OSTI]

    Takatoshi Ichikawa; Akira Iwamoto

    2010-12-20T23:59:59.000Z

    We discuss the possibility of the non-one-neutron emission channels in the cold fusion reaction $^{70}$Zn + $^{209}$Bi to produce the element Z=113. For this purpose, we calculate the evaporation-residue cross sections of one-proton, radiative-capture, and two-neutron emissions relative to the one-neutron emission in the reaction $^{70}$Zn + $^{209}$Bi. To estimate the upper bounds of those quantities, we vary model parameters in the calculations, such as the level-density parameter and the height of the fission barrier. We conclude that the highest possibility is for the 2n reaction channel, and its upper bounds are 2.4$%$ and at most less than 7.9% with unrealistic parameter values, under the actual experimental conditions of [J. Phys. Soc. Jpn. {\\bf 73} (2004) 2593].