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Sample records for bsub hffrfe studied

  1. Reactions of B/sub 12r/ with aliphatic free radicals: a pulse-radiolysis study

    International Nuclear Information System (INIS)

    The spectra of the intermediates formed in the reactions of B/sub 12r/ with the free radicals Br2-., CO2-., .CH2C(CH3)2OH, .C(CH3)2OH, . CH2CHO, and .CH(OH)CH2OH are reported. The results indicate that Br2-. oxidizes B/sub 12r/ to B/sub 12a/, via an inner-sphere mechanism, and CO2- . reduces B/sub 12r/ to B/sub 12s/. All the aliphatic free radicals studied, .R, react with B/sub 12r/, yielding as the first product a pseudocoenzyme denoted Co/sup III/-R. Co/sup III/-CH2C(CH3)2OH is stable for over a second in the pH range 3 to 10 as is Co/sup III/-CH2CHO. The latter compound hydrolyzes in acid solutions to yield B/sub 12a/ and CH3CHO. Co/sup III/-C(CH3)2OH and Co/sup III/-CH(OH)CH2OH decompose heterolytically to yield mainly B/sub 12s/; a side reaction that probably yields Co/sup III/-H via a β-hydride shift is also observed. The kinetics of decomposition of Co/sup III/-CH(OH)CH2OH in neutral solutions are reported. No water elimination from the latter intermediate occurs. The reasons for the latter observation are discussed. 6 figures

  2. Study of the B{sub c}{sup +}→J/ψD{sub s}{sup +} and B{sub c}{sup +}→J/ψD{sub s}{sup ∗+} decays with the ATLAS detector

    Energy Technology Data Exchange (ETDEWEB)

    Aad, G. [Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Abbott, B. [Department of Physics, McGill University, Montreal, QC (Canada); Abdallah, J. [Department of Physics, University of Pennsylvania, Philadelphia, PA (United States); Abdinov, O. [Physics Department, University of Athens, Athens (Greece); Aben, R. [Fysiska institutionen, Lunds universitet, Lund (Sweden); and others

    2016-01-05

    The decays B{sub c}{sup +}→J/ψD{sub s}{sup +} and B{sub c}{sup +}→J/ψD{sub s}{sup ∗+} are studied with the ATLAS detector at the LHC using a dataset corresponding to integrated luminosities of 4.9 and 20.6 fb{sup -1} of pp collisions collected at centre-of-mass energies √s=7 TeV and 8 TeV, respectively. Signal candidates are identified through J/ψ→μ{sup +}μ{sup -} and D{sub s}{sup (∗)+}→ϕπ{sup +}(γ/π{sup 0}) decays. With a two-dimensional likelihood fit involving the B{sub c}{sup +} reconstructed invariant mass and an angle between the μ{sup +} and D{sub s}{sup +} candidate momenta in the muon pair rest frame, the yields of B{sub c}{sup +}→J/ψD{sub s}{sup +} and B{sub c}{sup +}→J/ψD{sub s}{sup ∗+}, and the transverse polarisation fraction in B{sub c}{sup +}→J/ψD{sub s}{sup ∗+} decay are measured. The transverse polarisation fraction is determined to be Γ{sub ±±}(B{sub c}{sup +}→J/ψD{sub s}{sup ∗+})/Γ(B{sub c}{sup +}→J/ψD{sub s}{sup ∗+})=0.38±0.23±0.07, and the derived ratio of the branching fractions of the two modes is B{sub B{sub c{sup +}→J/ψD{sub s{sup ∗}{sup +}}}}/B{sub B{sub c{sup +}→J/ψD{sub s{sup +}}}}=2.8 {sub -0.8}{sup +1.2}±0.3, where the first error is statistical and the second is systematic. Finally, a sample of B{sub c}{sup +}→J/ψπ{sup +} decays is used to derive the ratios of branching fractions B{sub B{sub c{sup +}→J/ψD{sub s{sup +}}}}/B{sub B{sub c{sup +}→J/ψπ{sup +}}}=3.8±1.1±0.4±0.2 and B{sub B{sub c{sup +}→J/ψD{sub s{sup ∗}{sup +}}}}/B{sub B{sub c{sup +}→J/ψπ{sup +}}}=10.4±3.1±1.5±0.6, where the third error corresponds to the uncertainty of the branching fraction of D{sub s}{sup +}→ϕ(K{sup +}K{sup -})π{sup +} decay. The available theoretical predictions are generally consistent with the measurement.

  3. Theoretical study of hydrogen adsorption on Ca-decorated C{sub 48}B{sub 12} clusters

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Pengtang; Chen, Hongshan, E-mail: chenhs@nwnu.edu.cn [Key Laboratory of Atomic and Molecular Physics & Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China)

    2015-09-15

    The hydrogen adsorption on Ca-decorated C{sub 48}B{sub 12} clusters is studied using density functional theory. The favorable binding site for Ca atom is the hexagonal C{sub 4}B{sub 2} rings. The strong interaction between Ca atoms and C{sub 48}B{sub 12} cluster hinders the aggregation of Ca atoms on the cluster surface. C{sub 48}B{sub 12} is an electron deficient system with a large electron affinity of 2.952 eV. The decorated Ca atoms transfer their electrons to the cluster easily. The net charges on the Ca atoms are in the range of 1.101 to 1.563 e. When H{sub 2} molecules approach the Ca atoms, they are moderately polarized and adsorbed around the Ca atoms in molecular form. The adsorption strength can reach up to 0.133 eV/H{sub 2}. Each Ca atom in the Ca-decorated C{sub 48}B{sub 12} complexes can adsorb three H{sub 2} molecules. The fully decorated C{sub 48}B{sub 12}Ca{sub 6} can hold up to 18 H{sub 2} molecules.

  4. Study on the optical properties of ErBa{sub 3}B{sub 9}O{sub 18} crystals

    Energy Technology Data Exchange (ETDEWEB)

    He, Ming, E-mail: heming@djtu.edu.cn [Department of Physics, College of Science, Dalian Jiaotong University, Dalian 116028 (China); Liu, T.Z. [Liaoning Key Materials Laboratory for Railway, College of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028 (China); Qiu, M.H. [Department of Physics, College of Science, Dalian Jiaotong University, Dalian 116028 (China); Zhang, Z.H. [Liaoning Key Materials Laboratory for Railway, College of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028 (China); Zhu, Y.Z.; Song, Z.; Xiu, J.L. [Department of Physics, College of Science, Dalian Jiaotong University, Dalian 116028 (China)

    2015-01-01

    The X-ray diffraction and spectral properties of optical crystals ErBa{sub 3}B{sub 9}O{sub 18} were investigated systematically. Single crystal X-ray diffraction (XRD) spectra were studied and space group forbidden XRD peaks were found as a result of stacking faults. Then, the transition spectral properties of the material were examined from optical absorption data. A wide band emission centering at 450 nm was found when the crystal was excited by UV light. The studies indicate that ErBa{sub 3}B{sub 9}O{sub 18} may find applications in thin disk laser or phosphor.

  5. Electronic and thermal properties of B{sub 2}-type AlRE intermetallic compounds: A first principles study

    Energy Technology Data Exchange (ETDEWEB)

    Pagare, Gitanjali, E-mail: gita_pagare@yahoo.co.i [Department of Physics, Govt. M.L.B. Girls P.G. College, Bhopal 462002 (India); Srivastava, Vipul, E-mail: vips73@yahoo.co [Department of Physics, NRI Institute of Research and Technology, Bhopal 462023 (India); Sanyal, Sankar P., E-mail: sankarsanyal@gmail.co [Department of Physics, Barkatullah University, Bhopal 462026 (India); Rajagopalan, M., E-mail: mraja1948@gmail.co [Crystal Growth Centre, Anna University, Chennai 600025 (India)

    2011-02-01

    The ground state electronic structure and thermal properties of B{sub 2}-type intermetallic compounds AlRE (RE: Pm, Sm, Eu, Tb, Gd and Dy) have been studied using a self-consistent tight-binding linear muffin-tin orbital (TB-LMTO) method at ambient as well as at high pressure. These compounds show metallic behavior under ambient condition. The band structure, total energy, density of states and ground state properties like lattice parameter, bulk modulus are calculated in the present work. The Debye-Grueneisen model is used to calculate the Debye temperature and the Grueneisen constant. The calculated results are in good agreement with the reported experimental and other theoretical results. The variation in the Debye temperature with pressure has also been reported. We present a detailed analysis of the role of f electrons of RE in the AlRE system. -- Research Highlights: {yields} The electronic and thermal properties of B{sub 2}-type AlRE (RE: Pm, Sm, Eu, Gd, Tb and Dy) have been studied using the first principles TB-LMTO method. {yields} Thermal properties have been calculated using the DG model. {yields} The band structure indicates the metallic nature of the present intermetallics. {yields} The variation in the Debye temperature with pressure has also been reported. The possibility of structural phase transformation is predicted. {yields} Anomalous behavior in DOS is observed under compression, which may be due to the delocalization of f electrons under pressure.

  6. Neutron diffraction studies of magnetic ordering in superconducting ErNi{sub 2}B{sub 2}C and TmNi{sub 2}B{sub 2}C in an applied magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Toft, K.N

    2004-01-01

    The field-induced magnetic structures of ErNi{sub 2}B{sub 2}C and TmNi{sub 2}B{sub 2}C in are especially interesting because the field suppresses the superconducting order parameter and therefore the magnetic properties can be studied while varying the strength of superconductivity. ErNi{sub 2}B{sub 2}C: For magnetic fields along all three symmetry directions, the observed magnetic structures have a period corresponding to the Fermi surface nesting structure. The phase diagrams present all the observed magnetic structures. Two results remain unresolved: 1. When applying the magnetic field along [010], the minority domain (Q{sub N}{sup B} = (0,Q,0) with moments perpendicular to the field) shows no signs of hysteresis. I expected it to be a meta-stable state, which would be gradually suppressed by a magnetic field, and when decreasing the field it would not reappear until some small field of approximately 0.1 T. 2. When the field is applied along [110], the magnetic structure rotates a small angle of 0.5 degrees away from the symmetry direction. TmNi{sub 2}B{sub 2}C: A magnetic field applied in the [100] direction suppresses the zero field magnetic structure Q{sub F} = (0.094,0.094,0) (T{sub N} = 1.6 K), in favor of the Fermi surface nesting structure Q{sub N} = (0.483,0,0). The appearance of the Q{sub N} phase was initially believed to be caused by the suppression of superconductivity. This suppression should make it favorable to create a magnetic order with a Q-vector determined by the maximum in the magnetic susceptibility at the Fermi surface nesting vector Q{sub N}. The phase diagram for the magnetic structures is presented, however several properties of the Q{sub N} magnetic structure cannot be explained within any known models. Quadrupolar ordering is suggested as a possible candidate for explaining these features of the Q{sub N} structure. (au)

  7. Comparative study of thermal stability and crystallization kinetics of 70B{sub 2}O{sub 3}-30Bi{sub 2}O{sub 3} and 70B{sub 2}O{sub 3}-30PbO glasses

    Energy Technology Data Exchange (ETDEWEB)

    Shaaban, Essam R., E-mail: esam_ramadan2008@yahoo.co [Physics Department, Faculty of Science, Qassium University, Buridah 51452 (Saudia Arabia) and Physics Department, Faculty of Science, Al-Azhar University, P.O. Box 71452, Assiut (Egypt)

    2011-02-01

    Glasses with compositions 70B{sub 2}O{sub 3}-30Bi{sub 2}O{sub 3} and 70B{sub 2}O{sub 3}-30PbO have been prepared and studied by differential thermal analysis (DTA). The crystallization kinetics of the glasses were investigated under non-isothermal conditions. From the dependence of glass-transition temperature (T{sub g}) on heating rate, the activation energy for the glass transition was derived. Similarly the activation energy of the crystallization process was determined. Thermal stability of these glasses were achieved in terms of the characteristic temperatures, such as glass-transition temperature, T{sub g}, onset temperature of crystallization, T{sub in}, temperature corresponding to the maximum crystallization rate, T{sub p}, beside the kinetic parameters, K(T{sub g}) and K(T{sub p}). The results revealed that 70B{sub 2}O{sub 3}-30PbO is more stable than 70B{sub 2}O{sub 3}-30Bi{sub 2}O{sub 3}. The crystallization mechanism is characterized for both 70B{sub 2}O{sub 3}-30Bi{sub 2}O{sub 3} and 70B{sub 2}O{sub 3}-30PbO glasses (kinetic exponent n=2.06 for 70B{sub 2}O{sub 3}-30Bi{sub 2}O{sub 3}, and n=3.03 for 70B{sub 2}O{sub 3}-30PbO). The phases at which the glass crystallizes after the thermal process were identified by X-ray diffraction.

  8. Fluorescence enhancement of the aflatoxin B{sub 1} by forming inclusion complexes with some cyclodextrins and molecular modeling study

    Energy Technology Data Exchange (ETDEWEB)

    Aghamohammadi, Mohammad [Department of Chemistry, Faculty of Science, Tarbiat Modarres University, P.O. Box 14115-111, Tehran (Iran, Islamic Republic of); Alizadeh, Naader [Department of Chemistry, Faculty of Science, Tarbiat Modarres University, P.O. Box 14115-111, Tehran (Iran, Islamic Republic of)], E-mail: alizaden@modares.ac.ir

    2007-12-15

    The interaction between the aflatoxin B{sub 1} (AFB{sub 1}) and three cyclodextrins, {alpha}-cyclodextrin ({alpha}-CD), {beta}-cyclodextrin ({beta}-CD) and heptakis-2,6-dimethyl-o-{beta}-cyclodextrin (ome-CD), was studied by spectrofluorescence technique. It was found that the inclusion association behavior occurs for the complexes of cyclodextrins with AFB{sub 1}. The fluorescence of AFB{sub 1} is generally enhanced in the complexes with cyclodextrins in aqueous solutions. The inclusion complex constants of the three types of cyclodextrins at different temperatures were evaluated from Benesi-Hildebrand plot and also by non-linear regression analysis. These cyclodextrins can only form the 1:1 (host:guest) inclusion complex in the studied temperature range of 20-50 deg. C. The enthalpy ({delta}H{sup o}) and entropy ({delta}S{sup o}) changes of complexation were extracted from the temperature dependency of complex formation constants (K). Temperature-dependent measurements showed that the association step is controlled by enthalpy-entropy compensation effect. The use of ome-CD generally resulted in the greatest fluorescence intensity. On the other hand, the discrepancy between the exhibited enhanced fluorescence and thermodynamic parameters ({delta}G{sup o}) is proposed to be different only by the orientation of the AFB{sub 1} within the cyclodextrin cavity. To find the most favorable structure, the geometry of complex was investigated by molecular modeling approach employing the semiemperical HF-SCF calculations.

  9. Moessbauer study of the phase distribution of Fe{sub 78-x}Al{sub x}Si{sub 9}B{sub 13} powder

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, D.R. de E-mail: denis@macbeth.if.usp.br; Partiti, C.S.M

    2001-05-01

    In this work, by using X-ray diffraction, magnetization and Moessbauer measurements, magnetic and structural properties of Fe{sub 78-x}Al{sub x}Si{sub 9}B{sub 13} (x=10, 20, 30) have been studied. These three sets of specimens in nominal composition Fe{sub 78-x}Al{sub x}Si{sub 9}B{sub 13} were produced by mechanically processing blended Fe, Al, B and Si powders, using different times in the range from 2 up to 300 h. Moessbauer spectra show a strong line broadening and were fitted by considering Gaussian distributions of hyperfine fields. The crystalline phase present in the spectra was identified as {alpha}-Fe. Magnetic hyperfine data are discussed in conjunction with X-ray diffraction and magnetic measurements.

  10. Effect of vitamin B/sub 6/ on the neurotoxicity and pharmacology of desmethylmisonidazole and misonidazole: clinical and laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, C.N.; Hirst, V.K.; Brown, D.M.; Halsey, J.

    1984-08-01

    The clinical usefulness of misonidazole (MISO) and desmethylmisonidazole (DMM) is severely limited by neurotoxicity. Based on theoretical considerations and on laboratory data suggesting that pyridoxine (PN) decreased MISO toxicity in mice. The authors attempted to ameliorate the clinical neuropathy of DMM using oral PN. Pharmacokinetic analysis suggested interaction of PN and DMM but no protection against neuropathy was observed. Serial experiments with C3H and BALB/c mice were done using various forms of vitamin B/sub 6/ (PN, pyridoxal, pyridoxal phosphate) administered orally and i.p. No consistent protection was observed. Dexamethasone did not alter MISO toxicity in mice, contrary to the clinical findings. They conclude that vitamin B/sub 6/ is not useful in preventing clinical neurotoxicity of MISO or DMM.

  11. Synthesis and photoluminescence study of Dy{sup 3+} doped Sr{sub 3}B{sub 2}O{sub 6}: Nanophosphors

    Energy Technology Data Exchange (ETDEWEB)

    Neharika,, E-mail: neharikasinghwazir@gmail.com; Kumar, Vinay, E-mail: neharikasinghwazir@gmail.com [School of Physics, Shri Mata Vaishno Devi University, Katra-182320, J and K (India); Ntwaeaborwa, O. M.; Swart, H. C. [Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein ZA9300 (South Africa)

    2014-04-24

    In present paper, the combustion method synthesis of Dy{sup 3+} doped Sr{sub 3}B{sub 2}O{sub 6} nanophosphor and their luminescent properties have been reported. The crystalline structure and morphology of nanophosphors was confirmed and verify by the Xray powder diffraction (XRD) and transmission electron microscopy (TEM). The spectral properties of the Sr{sub 3}B{sub 2}O{sub 6}:Dy{sup 3+} nanophosphors have been studied with the photoluminescence (PL) spectroscopy. Under 300nm excitation, the PL emission shows three peaks at 482, 575 and 664 nm, corresponding to the {sup 4}F{sub 9/2}→{sup 6}H{sub 15/2}, {sup 4}F{sub 9/2}→{sup 6}H{sub 13/2} and {sup 4}F{sub 9/2}→{sup 4}H{sub 11/2} transition states. The 1931 CIE diagram gives the coordinates (x, y) as (0.38099, 0.40418) correspond to the shade of yellowish white emission of the Dy{sup 3+} ion which can be used as w-LED phosphors.

  12. Magnetoimpedance studies on laser and microwave annealed Fe{sub 66}Ni{sub 7}si{sub 7}B{sub 20} ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Kotagiri, Ganesh [Advanced Magnetic Materials Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India); Ramarao, S.D. [Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India); Markandeyulu, G., E-mail: mark@iitm.ac.in [Advanced Magnetic Materials Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India)

    2015-05-15

    Magnetoimpedance (MI) has been investigated in the laser and microwave annealed Fe{sub 66}Ni{sub 7}Si{sub 7}B{sub 20} ribbons. The largest MI [(MI){sub m}] values of the ribbons annealed using laser with energies of 150, 200 and 250 mJ/pulse (mJp) are 25% (at 7 MHz), 30% (at 5 MHz) and 21% (at 7 MHz) respectively. The effect of domain wall pinning on MI was observed as field insensitive regions in the MI profiles in the ribbon annealed using 150 mJp energy. Flower shaped grains in amorphous matrix in the ribbon annealed with 200 mJp energy are responsible for highest (MI){sub m} due to the least anisotropy. In the ribbons annealed for 40, 45 and 50 min at 400 °C using microwaves, (MI){sub m} values are 35% (at 5 MHz), 46% (at 6 MHz) and 29% (at 7 MHz) respectively. The large DC conductivity and the least anisotropy (smallest H{sub k} values) in the ribbon microwave annealed for 45 min at 400 °C resulted in (MI){sub m} reaching its highest value in the ribbons investigated. - Highlights: • Magnetoimpedance studied on Fe{sub 66}Ni{sub 7}Si{sub 7}B{sub 20} ribbons annealed using laser/microwaves. • Domain wall pinning observed in the ribbon annealed with 150 mJ/pulse of laser. • Flower shaped grains observed in the ribbon annealed with 200 mJ/pulse of laser. • Large magnetoimpedance and least anisotropy observed in the above ribbon. • Microwave annealed ribbons exhibited conductivity-magnetoimpedance correlation.

  13. Characterization of μ-oxo-(BsubPc)2 in Multiple Organic Photovoltaic Device Architectures: Comparing against and Combining with Cl-BsubPc.

    Science.gov (United States)

    Castrucci, Jeffrey S; Garner, Richard K; Dang, Jeremy D; Thibau, Emmanuel; Lu, Zheng-Hong; Bender, Timothy P

    2016-09-21

    We demonstrate the first application of a unique boron subphthalocyanine (BsubPc) derivative, the oxygen bridged dimer μ-oxo-(BsubPc)2, as a multifunctional material within planar heterojunction organic photovoltaic (OPV) devices. We first explored the pairing of μ-oxo-(BsubPc)2 with well-known electron accepting and electron donating materials to explore its basic functionality. These preliminary device structures and metrics indicated that μ-oxo-(BsubPc)2 is best applied as an electron donating material when used in simple bilayer structures, as it yielded comparable OPV device efficiencies to that of the more well-established and highly optimized chloro-boron subphthalocyanine (Cl-BsubPc) OPV device structures. Thereafter we established that the HOMO/LUMO energy levels of μ-oxo-(BsubPc)2 are well-placed to apply it as a bifunctional donor/acceptor interlayer material in both energy and charge cascade OPV device architectures. Within this context, we found that μ-oxo-(BsubPc)2 was particularly effective in a charge cascade device as an interlayer between Cl-BsubPc and C70. We finally found evidence of an alloying-like effect for devices with mixed electron donor layers of (Cl-BsubPc) and μ-oxo-(BsubPc)2, achieved through co-deposition. The overarching conclusion is therefore that μ-oxo-(BsubPc)2 has the ability to improve the performance of Cl-BsubPc OPV devices and is a multifunctional material worthy of further study.

  14. Structural and photoluminescence study of Er-Yb codoped nanocrystalline ZrO{sub 2}-B{sub 2}O{sub 3} solid solution

    Energy Technology Data Exchange (ETDEWEB)

    Salas, P. [Centro de Fisica Aplicada y Tecnologia Avanzada, Universidad Nacional Autonoma de Mexico, A.P. 1-1010, Queretaro 76000 (Mexico); Borja-Urby, R. [Grupo de Espectroscopia de Materiales Avanzados y nanoestructurados (EMANA), Centro de Investigaciones en Optica, A. C., Loma del Bosque 115, Col. Lomas del Campestre, C.P. 37150 Leon, Gto. (Mexico); Diaz-Torres, L.A., E-mail: ditlacio@cio.mx [Grupo de Espectroscopia de Materiales Avanzados y nanoestructurados (EMANA), Centro de Investigaciones en Optica, A. C., Loma del Bosque 115, Col. Lomas del Campestre, C.P. 37150 Leon, Gto. (Mexico); Rodriguez, G. [Centro de Fisica Aplicada y Tecnologia Avanzada, Universidad Nacional Autonoma de Mexico, A.P. 1-1010, Queretaro 76000 (Mexico); Vega, M. [Centro de Geociencias, Universidad Nacional Autonoma de Mexico, A.P. 1-1010, Queretaro 76000 (Mexico); Angeles-Chavez, C. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas 152, A.P. 14-805, 07730 Mexico, DF (Mexico)

    2012-09-20

    Codoped Er{sup 3+} and Yb{sup 3+} nanocrystalline ZrO{sub 2}-B{sub 2}O{sub 3} phosphor obtained by a modified sol-gel method is demonstrated. The addition of up to 2.5 mol% B{sub 2}O{sub 3} to nanocrystalline ZrO{sub 2}:Yb(2%), Er(1%) keep the tetragonal rare-earth stabilized ZrO{sub 2} phase; whereas higher B{sub 2}O{sub 3} content destabilize the tetragonal phase, leading to the tetragonal to monoclinic transition with no tetragonal ZrO{sub 2} phase segregation. Visible upconversion of the luminescent active ions, Er{sup 3+} and Yb{sup 3+}, depend strongly on B{sub 2}O{sub 3} content. The PL intensity is strongly quenched for high B{sub 2}O{sub 3} content due to increasing multiphonon relaxation processes related to B-O and B-O-B vibronic modes.

  15. Lattice measurement of B{sub B{sub s}} with a chiral light quark action

    Energy Technology Data Exchange (ETDEWEB)

    Blossier, B.

    2007-01-15

    The computation on the lattice of the bag parameter B{sub B{sub s}} associated to the B{sub S}-B{sub S} mixing amplitude in the Standard Model is presented. The estimation has been made by combining the static limit of HQET and the Neuberger light quark action which preserves the chiral symmetry on the lattice. We find B{sub B{sub S}}{sup MSstat}(m{sub b})=0.92(3). (orig.)

  16. Study of domain structure and magnetization reversal after thermal treatments in Fe{sub 40}Co{sub 38}Mo{sub 4}B{sub 18} microwires

    Energy Technology Data Exchange (ETDEWEB)

    Klein, P. [Institute of Physics, Faculty of Science, UPJS, Park Angelinum 9, 041 54 Kosice (Slovakia); Varga, R., E-mail: rvarga@upjs.sk [Institute of Physics, Faculty of Science, UPJS, Park Angelinum 9, 041 54 Kosice (Slovakia); Badini-Confalonieri, G.A.; Vazquez, M. [Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Ines de la Cruz 3, 28049 Cantoblanco, Madrid (Spain)

    2011-12-15

    We have studied the effect of thermal treatment on the magnetic domain structure and magnetic reversal process of amorphous and nanocrystalline Fe{sub 40}Co{sub 38}Mo{sub 4}B{sub 18} microwires. The domain structure and the magnetization reversal of amorphous FeCoMoB microwires reflect the complex stress distribution introduced by the glass coating. Hence, the thickness of radial domain structure decreases with temperature and the temperature dependence of the switching field presents a discontinuous behavior. After nanocrystallization, the domain structure of FeCoMoB microwire is almost constant within the temperature range 10-400 K and the switching field decreases almost linearly with temperature mostly because of the decrease of saturation magnetization. - Highlights: > Nanocrystalline FeCoMoB microwires are characterized by the high Curie temperature. > Nanocrystalline FeCoMoB microwires remains bistable even in nanocrystalline state. > Nanocrystalline FeCoMoB microwires are characterized by high magnetic stability in a wide temperature range.

  17. Spectroscopic studies on the molecular interaction between salicylic acid and riboflavin (B{sub 2}) in micellar solution

    Energy Technology Data Exchange (ETDEWEB)

    Bhattar, S.L.; Kolekar, G.B. [Fluorescence Spectroscopy Research Laboratory, Department of Chemistry, Shivaji University, Kolhapur-416 004, Maharashtra (India); Patil, S.R., E-mail: srp_fsl@rediffmail.co [Fluorescence Spectroscopy Research Laboratory, Department of Chemistry, Shivaji University, Kolhapur-416 004, Maharashtra (India)

    2010-03-15

    The interaction between salicylic acid (SA) and riboflavin (RF) was studied by Fluorescence Resonance Energy Transfer (FRET) in micellar solution. The riboflavin strongly quenches the intrinsic fluorescence of SA by radiative energy transfer. The extent of energy transfer in sodium dodecyl sulphate (SDS) micellar solution of different concentration is quantified from the energy transfer efficiency data. It is seen that the energy transfer is more efficient in the micellar solution. The critical energy transfer distance (R{sub 0}) was determined from which the mean distance between SA and RF molecules was calculated. The quenching was found to fit into Stern-Volmer relation. The results on variation of Stern-Volmer constant (K{sub sv}) with quencher concentration obtained at different temperatures suggested the formation of complex between SA and RF. The association constant of complex formation was estimated and found to decrease with temperature. The values of thermodynamic parameters DELTAH, DELTAG and DELTAS at different temperatures were estimated and the results indicated that the molecular interaction between SA and RF is electrostatic in nature.

  18. Magnetoimpedance studies on urine treated Co{sub 66}Ni{sub 7}Si{sub 7}B{sub 20} ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Kotagiri, Ganesh [Advanced Magnetic Materials Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India); Markandeyulu, G., E-mail: mark@iitm.ac.in [Advanced Magnetic Materials Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India); Doble, Mukesh; Nandakumar, V. [Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600036 (India)

    2015-11-15

    Magnetoimpedance (MI) response of Co{sub 66}Ni{sub 7}Si{sub 7}B{sub 20} ribbons treated with artificial urine with protein bovine serum albumin (BSA), artificial urine without protein BSA and healthy male urine was studied as a function of time of incubation. The maximum MI [(MI){sub m}] values of the ribbons treated with artificial urine without protein (RTAU) after 3 h, 6 h, 12 h and 24 h of incubation are 30% (at 4 MHz), 15% (at 5 MHz), 14% (at 10 MHz) and 8% (at 13 MHz) respectively. On the other hand, the respective (MI){sub m} values of the ribbons treated with artificial urine with protein (RTAUP) are 33% (at 4 MHz), 25% (at 5 MHz), 20% (at 8 MHz) and 15% (12 MHz). However (MI){sub m} values of the ribbons treated with healthy male urine (RTHMU) after 4 h, 5 h, 10 h and 15 h of incubation are 71% (at 3 MHz), 57% (at 3 MHz), 25% (at 6 MHz) and 25% (at 5 MHz), respectively. The saturation magnetization (M{sub s}) values of RTAU after 3 h, 6 h, 12 h and 24 h of incubation are 71 emu/g, 65 emu/g, 63 emu/g and 60 emu/g respectively whereas, the respective M{sub s} values of RTAUP are 73 emu/g, 69 emu/g, 67 emu/g and 64 emu/g. The M{sub s} values of RTHMU after 4 h, 5 h, 10 h and 15 h of incubation are 96 emu/g, 90 emu/g, 75 emu/g and 75 emu/g respectively. The decrease in M{sub s} and (MI){sub m} values in RTAU and RTAUP compared to as-quenched ribbon is related to the amounts of various elements etched out from the ribbons and increased surface roughness. The M{sub s} and (MI){sub m} values of RTHMU are seen to have increased after 4 h and 5 h of incubation, due to strain relaxation through removal of strain developed during rapid quenching of the ribbons. On the other hand, the M{sub s} and (MI){sub m} values of RTHMU after 10 h and 15 h have decreased due to deterioration of the surface of the ribbons and thus, increase in magnetic (surface) anisotropy. The decrease in (MI){sub m} and M{sub S} of RTAU with the time of incubation are more rapid compared to that

  19. B{sub 4}C thin films for neutron detection

    Energy Technology Data Exchange (ETDEWEB)

    Hoeglund, Carina [European Spallation Source ESS AB, P.O. Box 176, SE-221 00 Lund (Sweden); Department of Physics, Chemistry and Biology (IFM), Thin Film Physics Division, Linkoeping University, SE-581 83 Linkoeping (Sweden); Birch, Jens; Jensen, Jens; Hultman, Lars [Department of Physics, Chemistry and Biology (IFM), Thin Film Physics Division, Linkoeping University, SE-581 83 Linkoeping (Sweden); Andersen, Ken; Hall-Wilton, Richard [European Spallation Source ESS AB, P.O. Box 176, SE-221 00 Lund (Sweden); Bigault, Thierry; Buffet, Jean-Claude; Correa, Jonathan; Esch, Patrick van; Guerard, Bruno; Piscitelli, Francesco [Institute Laue Langevin, Rue Jules Horowitz, FR-380 00 Grenoble (France); Khaplanov, Anton [European Spallation Source ESS AB, P.O. Box 176, SE-221 00 Lund (Sweden); Institute Laue Langevin, Rue Jules Horowitz, FR-380 00 Grenoble (France); Vettier, Christian [European Spallation Source ESS AB, P.O. Box 176, SE-221 00 Lund (Sweden); European Synchrotron Radiation Facility, BP 220, FR-380 43 Grenoble Cedex 9 (France); Vollenberg, Wilhelmus [Vacuum, Surfaces and Coatings Group (TE/VSC), CERN, CH-1211 Geneva 23 (Switzerland)

    2012-05-15

    Due to the very limited availability of {sup 3}He, new kinds of neutron detectors, not based on {sup 3}He, are urgently needed. Here, we present a method to produce thin films of {sup 10}B{sub 4}C, with maximized detection efficiency, intended to be part of a new generation of large area neutron detectors. B{sub 4}C thin films have been deposited onto Al-blade and Si wafer substrates by dc magnetron sputtering from {sup nat}B{sub 4}C and {sup 10}B{sub 4}C targets in an Ar discharge, using an industrial deposition system. The films were characterized with scanning electron microscopy, elastic recoil detection analysis, x-ray reflectivity, and neutron radiography. We show that the film-substrate adhesion and film purity are improved by increased substrate temperature and deposition rate. A deposition rate of 3.8 A/s and substrate temperature of 400 deg. C result in films with a density close to bulk values and good adhesion to film thickness above 3 {mu}m. Boron-10 contents of almost 80 at. % are obtained in 6.3 m{sup 2} of 1 {mu}m thick {sup 10}B{sub 4}C thin films coated on Al-blades. Initial neutron absorption measurements agree with Monte Carlo simulations and show that the layer thickness, number of layers, neutron wavelength, and amount of impurities are determining factors. The study also shows the importance of having uniform layer thicknesses over large areas, which for a full-scale detector could be in total {approx}1000 m{sup 2} of two-side coated Al-blades with {approx}1 {mu}m thick {sup 10}B{sub 4}C films.

  20. Low-temperature sequential pulsed chemical vapor deposition of ternary B{sub x}Ga{sub 1-x}N and B{sub x}In{sub 1-x}N thin film alloys

    Energy Technology Data Exchange (ETDEWEB)

    Haider, Ali, E-mail: ali.haider@bilkent.edu.tr, E-mail: biyikli@unam.bilkent.edu.tr; Kizir, Seda; Ozgit-Akgun, Cagla; Biyikli, Necmi, E-mail: ali.haider@bilkent.edu.tr, E-mail: biyikli@unam.bilkent.edu.tr [National Nanotechnology Research Center (UNAM), Bilkent University, Bilkent, Ankara 06800, Turkey and Institute of Materials Science and Nanotechnology, Bilkent University, Bilkent, Ankara 06800 (Turkey); Okyay, Ali Kemal [National Nanotechnology Research Center (UNAM), Bilkent University, Bilkent, Ankara 06800 (Turkey); Institute of Materials Science and Nanotechnology, Bilkent University, Bilkent, Ankara 06800 (Turkey); Department of Electrical and Electronics Engineering, Bilkent University, Bilkent, Ankara 06800 Turkey (Turkey)

    2016-01-15

    In this work, the authors have performed sequential pulsed chemical vapor deposition of ternary B{sub x}Ga{sub 1-x}N and B{sub x}In{sub 1-x}N alloys at a growth temperature of 450 °C. Triethylboron, triethylgallium, trimethylindium, and N{sub 2} or N{sub 2}/H{sub 2} plasma have been utilized as boron, gallium, indium, and nitrogen precursors, respectively. The authors have studied the compositional dependence of structural, optical, and morphological properties of B{sub x}Ga{sub 1-x}N and B{sub x}In{sub 1-x}N ternary thin film alloys. Grazing incidence X-ray diffraction measurements showed that boron incorporation in wurtzite lattice of GaN and InN diminishes the crystallinity of B{sub x}Ga{sub 1-x}N and B{sub x}In{sub 1-x}N sample. Refractive index decreased from 2.24 to 1.65 as the B concentration of B{sub x}Ga{sub 1-x}N increased from 35% to 88%. Similarly, refractive index of B{sub x}In{sub 1-x}N changed from 1.98 to 1.74 for increase in B concentration value from 32% to 87%, respectively. Optical transmission band edge values of the B{sub x}Ga{sub 1-x}N and B{sub x}In{sub 1-x}N films shifted to lower wavelengths with increasing boron content, indicating the tunability of energy band gap with alloy composition. Atomic force microscopy measurements revealed an increase in surface roughness with boron concentration of B{sub x}Ga{sub 1-x}N, while an opposite trend was observed for B{sub x}In{sub 1-x}N thin films.

  1. Studies of the local distortions and the EPR parameters for Cu{sup 2+} in xLi{sub 2}O-(30-x)Na{sub 2}O-69.5B{sub 2}O glasses

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Chang-Chun; Wu, Shao-Yi; Kuang, Min-Quan; Hu, Xian-Fen; Li, Guo-Liang [Univ. of Electronic Science and Technology of China, Chengdu (China). Dept. of Applied Physics

    2016-07-01

    The local distortions and electron paramagnetic resonance (EPR) parameters for Cu2+ in lithium sodium borate (LNB) glasses xLi{sub 2}O.(30-x).Na{sub 2}O.69.5B{sub 2}O{sub 3} (5 ≤ x ≤ 25 mol%) are theoretically studied at various concentrations x in a consistent way. Owing to the Jahn-Teller effect, the [CuO{sub 6}]{sup 10-} clusters are found to experience the significant tetragonal elongations of 16% along C{sub 4} axis. Despite the nearly unchanging observed g factors, measured d-d transition band (or cubic field parameter Dq) shows remarkable linear increases with concentration x, whose influences on g {sub parallel} and g {sub perpendicular} {sub to} are actually cancelled by the linearly increasing covalency factor N and relative elongation ratio η with x. The almost unvarying hyperfine structure constants are attributed to the fact that the influences of the linearly increasing N and the linearly decreasing core polarisation constant κ largely cancel one another. The microscopic mechanisms of the above concentration dependences for these quantities are illustrated from mixed alkali effect (modification of B{sub 2}O{sub 3} network by transforming some BO{sub 3} units into BO{sub 4} ones with variations in modifier Li{sub 2}O concentration).

  2. Gastric emptying in patients with vitamin B{sub 12} deficiency

    Energy Technology Data Exchange (ETDEWEB)

    Yagci, Muenci; Yamac, Kadri; Acar, Kadir; Haznedar, Rauf [Department of Hematology, Gazi Medical School (Turkey); Cingi, Elif; Kitapci, Mehmet [Department of Nuclear Medicine, Gazi Medical School (Turkey)

    2002-09-01

    The clinical presentation of patients with vitamin B{sub 12} deficiency varies in a spectrum ranging from haematological disorders to neuropsychiatric diseases. In rare cases, orthostatic hypotension, impotence, constipation and urinary retention have been attributed to autonomic nervous system dysfunction due to vitamin B{sub 12} deficiency. The aim of this study was to evaluate the effect of vitamin B{sub 12} deficiency on autonomic nervous system function by studying gastric emptying times (T{sub 1/2}). Twenty patients with newly diagnosed vitamin B{sub 12} deficiency and 12 control patients with gastritis and normal vitamin B{sub 12} levels were enrolled in this study. Gastroduodenoscopy, endoscopic biopsy, histopathological evaluation of the biopsy specimens and radionuclide gastric emptying studies were performed. After vitamin B{sub 12} replacement therapy for 3 months, radionuclide gastric emptying studies were repeated. Mean gastric emptying T{sub 1/2} in patients before and after treatment and in controls were 103.83{+-}48.80 min, 90.00{+-}17.29 min and 74.55{+-}8.52 min, respectively. The difference in mean gastric emptying T{sub 1/2} between patients before treatment and controls was statistically significant (P<0.01). The statistically significant difference persisted after vitamin B{sub 12} treatment (P<0.05), though mean gastric emptying T{sub 1/2} was somewhat shorter. There were no positive or negative correlations between gastric emptying T{sub 1/2} and the following parameters: haemoglobin, vitamin B{sub 12} level and Helicobacter pylori positivity. In conclusion, gastric emptying T{sub 1/2} was prolonged in patients with vitamin B{sub 12} deficiency and this prolongation was not corrected after vitamin B{sub 12} replacement therapy. Although autonomic nervous system dysfunction due to vitamin B{sub 12} deficiency rarely gives rise to clinical manifestations, latent dysfunction demonstrated by laboratory tests seems to be a frequent phenomenon

  3. B{sub s}{sup 0}- anti B{sub s}{sup 0} mixing within minimal flavor-violating two-Higgs-doublet models

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Qin [Henan Normal University, Institute of Particle and Nuclear Physics, Xinxiang, Henan (China); Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Beijing (China); Li, Pei-Fu [Henan Normal University, Institute of Particle and Nuclear Physics, Xinxiang, Henan (China); Li, Xin-Qiang [Central China Normal University, Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Wuhan, Hubei (China); Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Beijing (China)

    2015-12-15

    In the ''Higgs basis'' for a generic 2HDM, only one scalar doublet gets a nonzero vacuum expectation value and, under the criterion of minimal flavor violation, the other one is fixed to be either color-singlet or color-octet, which are named as the type-III and type-C models, respectively. In this paper, the charged-Higgs effects of these two models on B{sub s}{sup 0}- anti B{sub s}{sup 0} mixing are studied. First of all, we perform a complete one-loop computation of the electro-weak corrections to the amplitudes of B{sub s}{sup 0}- anti B{sub s}{sup 0} mixing. Together with the up-to-date experimental measurements, a detailed phenomenological analysis is then performed in the cases of both real and complex Yukawa couplings of charged scalars to quarks. The spaces of model parameters allowed by the current experimental data on B{sub s}{sup 0}- anti B{sub s}{sup 0} mixing are obtained and the differences between type-III and type-C models are investigated, which is helpful to distinguish between these two models. (orig.)

  4. Observation of B{sub s}{sup 0}→χ{sub c1}ϕ decay and study of B{sup 0}→χ{sub c1,2}K{sup ⁎0} decays

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [Fakultät Physik, Technische Universität Dortmund, Dortmund (Germany); Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amerio, S. [Sezione INFN di Padova, Padova (Italy); Amhis, Y. [LAL, Université Paris-Sud, CNRS/IN2P3, Orsay (France); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universität Zürich, Zürich (Switzerland); Andreassen, R. [University of Cincinnati, Cincinnati, OH (United States); Andrews, J.E. [University of Maryland, College Park, MD (United States); and others

    2013-09-21

    The first observation of the decay B{sub s}{sup 0}→χ{sub c1}ϕ and a study of B{sup 0}→χ{sub c1,2}K{sup ⁎0} decays are presented. The analysis is performed using a dataset, corresponding to an integrated luminosity of 1.0 fb{sup −1}, collected by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. The following ratios of branching fractions are measured: (table) where the third uncertainty is due to the limited knowledge of the branching fractions of χ{sub c}→J/ψγ modes.

  5. Observation and characterization of the smallest borospherene, B{sub 28}{sup −} and B{sub 28}

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ying-Jin; Chen, Qiang; You, Xue-Rui; Ou, Ting; Zhao, Xiao-Yun; Li, Si-Dian, E-mail: hj.zhai@sxu.edu.cn, E-mail: lisidian@sxu.edu.cn, E-mail: junli@tsinghua.edu.cn, E-mail: lai-sheng-wang@brown.edu [Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006 (China); Zhao, Ya-Fan; Li, Jun, E-mail: hj.zhai@sxu.edu.cn, E-mail: lisidian@sxu.edu.cn, E-mail: junli@tsinghua.edu.cn, E-mail: lai-sheng-wang@brown.edu [Department of Chemistry and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084 (China); Li, Wei-Li; Jian, Tian; Wang, Lai-Sheng, E-mail: hj.zhai@sxu.edu.cn, E-mail: lisidian@sxu.edu.cn, E-mail: junli@tsinghua.edu.cn, E-mail: lai-sheng-wang@brown.edu [Department of Chemistry, Brown University, Providence, Rhode Island 02912 (United States); Zhai, Hua-Jin, E-mail: hj.zhai@sxu.edu.cn, E-mail: lisidian@sxu.edu.cn, E-mail: junli@tsinghua.edu.cn, E-mail: lai-sheng-wang@brown.edu [Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006 (China); State Key Laboratory of Quantum Optics and Quantum Optics Devices, Shanxi University, Taiyuan 030006 (China)

    2016-02-14

    Free-standing boron nanocages or borospherenes have been observed recently for B{sub 40}{sup −} and B{sub 40}. There is evidence that a family of borospherenes may exist. However, the smallest borospherene is still not known. Here, we report experimental and computational evidence of a seashell-like borospherene cage for B{sub 28}{sup −} and B{sub 28}. Photoelectron spectrum of B{sub 28}{sup −} indicated contributions from different isomers. Theoretical calculations showed that the seashell-like B{sub 28}{sup −} borospherene is competing for the global minimum with a planar isomer and it is shown to be present in the cluster beam, contributing to the observed photoelectron spectrum. The seashell structure is found to be the global minimum for neutral B{sub 28} and the B{sub 28}{sup −} cage represents the smallest borospherene observed to date. It is composed of two triangular close-packed B{sub 15} sheets, interconnected via the three corners by sharing two boron atoms. The B{sub 28} borospherene was found to obey the 2(n + 1){sup 2} electron-counting rule for spherical aromaticity.

  6. Proton-induced nanorod melting in a coating obtained from the pulsed laser ablation of W{sub 2}B{sub 5}/B{sub 4}C

    Energy Technology Data Exchange (ETDEWEB)

    Tadadjeu Sokeng, I., E-mail: ifriky@tlabs.ac.za [Department of Electrical, Electronics and Computer Engineering, French South African Institute of Technology/Cape Peninsula University of Technology, Bellville Campus, PO Box 1906, Bellville 7530 (South Africa); Electron Microscopy Unit, University of the Western Cape, Private bag x17, Bellville 7535 (South Africa); Ngom, B.D. [Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, 7129, PO Box 722, Somerset West, Western Cape Province (South Africa); UNESCO-UNISA Africa Chair in Nanosciences/Nanotechnology, College of Graduate Studies, University of South Africa (UNISA), Muckleneuk Ridge, PO Box 392, Pretoria (South Africa); Laboratoire de Photonique et de Nanofrabrication, Groupes de physique du Solide et Sciences des Matriaux (GPSSM), Facult des sciences et Techniques, Universit Cheikh Anta Diop de Dakar (UCAD), B.P. 25114 Dakar-Fann, Dakar (Senegal); Cummings, F. [Electron Microscopy Unit, University of the Western Cape, Private bag x17, Bellville 7535 (South Africa); Kotsedi, L. [Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, 7129, PO Box 722, Somerset West, Western Cape Province (South Africa); UNESCO-UNISA Africa Chair in Nanosciences/Nanotechnology, College of Graduate Studies, University of South Africa (UNISA), Muckleneuk Ridge, PO Box 392, Pretoria (South Africa); Msimanga, M. [iThemba LABS Gauten, Private Bag 11, WITS 2050, Johannesburg (South Africa); Maaza, M. [Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, 7129, PO Box 722, Somerset West, Western Cape Province (South Africa); UNESCO-UNISA Africa Chair in Nanosciences/Nanotechnology, College of Graduate Studies, University of South Africa (UNISA), Muckleneuk Ridge, PO Box 392, Pretoria (South Africa); and others

    2015-02-01

    Highlights: • Coatings from ablated B{sub 4}C/W{sub 2}B{sub 5} were irradiated with 900 keV protons. • Nanorod clusters were observed to melt and disperse. • Uniformly shaped nanorods were observed to grow. • Lateral diffusion of energy and lateral dispersion of matter were observed. - Abstract: Coatings obtained from pulsed laser ablated W{sub 2}B{sub 5}/B{sub 4}C were irradiated with 900keV protons at fluences ranging from about 1×10{sup 15}protons/cm{sup 2} to about 4×10{sup 15}protons/cm{sup 2}. Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to study the resulting structural effects. Clusters of nanorods were observed to disperse and reduce in number with increase in proton fluence. The atomic percentage of constituent elements were observed to vary with proton fluence, both within the nanorods and the film floor. Our results show that the structural effect of proton irradiation on the coating is lateral dispersion of matter.

  7. RE{sub 2}B{sub 8}O{sub 15} (RE = La, Pr, Nd). Syntheses of three new rare earth borates isotypic to Ce{sub 2}B{sub 8}O{sub 15}

    Energy Technology Data Exchange (ETDEWEB)

    Glaetzle, Matthias; Hoerder, Gregor J.; Huppertz, Hubert [Innsbruck Univ. (Austria). Inst. fuer Allgemeine, Anorganische und Theoretische Chemie

    2016-08-01

    The rare earth borates RE{sub 2}B{sub 8}O{sub 15} (RE = La, Pr, Nd) were synthesized in a Walker-type multianvil apparatus under conditions of 5.5 GPa and 1100 C. Starting from the corresponding rare earth oxides and boron oxide, the syntheses yielded crystalline products of all new compounds that allowed crystal structure analyses based on single-crystal X-ray diffraction data for La{sub 2}B{sub 8}O{sub 15} and Nd{sub 2}B{sub 8}O{sub 15}. The compound Pr{sub 2}B{sub 8}O{sub 15} could be characterized via X-ray powder diffractometry. The results show that the new compounds crystallize isotypically to Ce{sub 2}B{sub 8}O{sub 15} in the monoclinic space group P2/c. The infrared spectra of RE{sub 2}B{sub 8}O{sub 15} (RE = La, Pr, Nd) have also been studied.

  8. Surface quality improvement of B{sub 4}C particles for electroless copper coating by Cu activation and oxidation roughening methods

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jiyun [Joint Laboratory of Nuclear Materials and Service Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Shu, Guogang [China Nuclear Power Engineering Co., Ltd., Shenzhen (China); Wang, Wei [Joint Laboratory of Nuclear Materials and Service Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Li, Qiulin, E-mail: liql@sz.tsinghua.edu.cn [Joint Laboratory of Nuclear Materials and Service Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Liu, Wei [School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2015-09-15

    Highlights: • Cu activation increases surface activity by depositing Cu nano-crystals on B{sub 4}C. • The best result of Cu activation comes out at pH 12. • Oxidation roughening improves wettability of B{sub 4}C by aqueous solution. • Oxidation roughening promotes Cu nucleation on B{sub 4}C surface. - Abstract: Surface quality improvement by Cu activation and oxidation roughening process was studied during electroless coating Cu on boron carbide (B{sub 4}C) particles. The surface morphology was characterized by scanning electron microscope (SEM) and the phase identification was determined by X-ray diffraction (XRD) analysis. Two aspects concluding surface activation and surface roughening were investigated to understand the effect of each on Cu coating. Cu activation process increased surface activity of B{sub 4}C by pre-deposition Cu nano-crystals, which was effective and cost-saving when compared with conventional Pd activation method. The influence of activation pH on electroless Cu coating was discussed and a moderate pH 12 is suitable for Cu deposition. Surface roughening process availably promoted wettability of B{sub 4}C particles with aqueous solution. Etched pits were formed on B{sub 4}C surface and resulted in fresh surface exposed after oxidization roughening process, which was beneficial for Cu bonding and coating on B{sub 4}C surface.

  9. Ab Initio MO study on the nucleophilic oxirane ring opening of exo and endo Aflatoxin B{sub 1} 8,9-Oxide; Ekiso oyobi endo Aflatoxin B{sub 1} 8,9-Oxide no kyukaku kaikan hanno ni taisuru Ab Initio ho ni yoru kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Okajima, Toshiya; Hashikawa, Akane [Saga University, Saga (Japan). Department of Chemistry

    1999-08-10

    The difference of the reactivity for S{sub N}2 type oxirane ring opening of exo and endo Aflatoxin B{sub 1} (AFB{sub 1}) 8,9-oxide (exo-1 and endo-1, respectively) was analyzed with ab initio molecular orbital theory. All stationary points including transition-state structures were optimized with no geometry constraint at the RHF/3-21G basis set, and energies were evaluate at Becke3LYP/3-21G level based on the RHF/3-21G geometries. The calculation clarified the following three points: (1) the activation energy ({delta}E{sup {ne}}) for endo attacking of NH{sub 3} molecule (the reaction with exo derivatives containing exo-1) is considerably smaller than those for exo attacking (the reaction with endo ones containing endo-1), (2) the reactivity for nucleophilic oxirane ring opening is controlled by the distortion of LUMO{sub C-O} of oxirane ring, which is probably caused by exo/endo relationship between oxirane ring and five-membered dihydrofurano ring (B) with respect to A ring, and (3) the remaining part (inclusing coumarin skeleton) of AFB{sub 1} oxid has little influence on the geometry around the reaction center and the activation energy. (author)

  10. Low-temperature heat capacity and thermodynamic functions of vitamin B{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, A.V., E-mail: knyazevav@gmail.com; Smirnova, N.N.; Plesovskikh, A.S.; Shushunov, A.N.; Knyazeva, S.S.

    2014-04-01

    Graphical abstract: - Highlights: • Temperature dependence of heat capacity of vitamin B{sub 12} has been measured by precision adiabatic vacuum calorimetry. • The thermodynamic functions of the vitamin B{sub 12} have been determined for the range from T → 0 to 343 K. • The character of heterodynamics of structure was detected. • The thermal stability of cyanocobalamin was studied by differential scanning calorimetry. - Abstract: In the present work temperature dependence of heat capacity of vitamin B{sub 12} (cyanocobalamin) has been measured for the first time in the range from 6 to 343 K by precision adiabatic vacuum calorimetry. Based on the experimental data, the thermodynamic functions of the vitamin B{sub 12}, namely, the heat capacity, enthalpy H°(T) − H°(0), entropy S°(T) − S°(0) and Gibbs function G°(T) − H°(0) have been determined for the range from T → 0 to 343 K. The value of the fractal dimension D in the function of multifractal generalization of Debye's theory of the heat capacity of solids was estimated and the character of heterodynamics of structure was detected. The thermal stability of cyanocobalamin was also studied by differential scanning calorimetry.

  11. Association of vitamin b/sub 12/, serum ferritin and folate levels with recurrent oral ulceration

    International Nuclear Information System (INIS)

    Background: The pathophysiology of recurrent aphthous stomatitis or aphthous ulcers remains obscure but malnutrition is one of its contributory factors. There is some role of vitamin B/sub 12/, ferritin and folate in the development of these lesions. Objectives: To determine the relationship between recurrent aphthous stomatitis and levels of ferritin, folate and vitamin B/sub 12/. Studytype settings: This case control study was conducted at Immunoassay lab, NHRC and Department of Dentistry, ShaikhZayed Hospital, Lahore. Patients and Methods: Sixty patients of all ages and both genders having history of recurrent ulcers over the past period of 3-6 months. Similar number of healthy controls were chosen who were either attendants of the patients or staff of the hospital and did not have any history of aphthous ulcers. Proforma was filled for each participant and 5ml blood was drawn and tested for complete picture blood by Sismex, serum ferritin by ELISA (Biocheck), vitamin B/sub 12/ and RBC folate by IBL kits from USA. Results: Fifty seven (57) age and gender matched patients with recurrent aphthous ulcers and 57 normal healthy controls were studied.Anemia was present in 24(42.1%) patients and 18(31.6%) controls. Hematocrit levels were normal in 45(79%) patients and 40(70.2%) controls. Low levels of RBC folate was seen in 26(45.6%) patients and 26(45.6%) controls. Vitamin B/sub 12/ deficiency was present in 29(50.1%) patients and none of the controls. The low levels of ferritin was seen in 6(10.5%) patients and 18(31.5%) controls. Conclusions: Patients with recurrent aphthous ulcers had more hematinic deficiencies, particularly of vitamin B/sub 12/ as compared to controls. (author)

  12. Measurement of the B{sub S} lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Siccama, I.

    1996-10-07

    This thesis presents a measurement of the B{sub s} lifetime using 3 million hadronic Z decays collected by the DELPHI detector at LEP from 1991 to 1994. Decays of B{sub s} mesons are tagged by the reconstruction of a D{sub s}{sup -}{yields}{phi}{pi}{sup -}or D{sub s}{sup -}{yields}K{sup *0}K{sup -} decay (including the charge conjugated states of these decay modes). The decay time is obtained by reconstructing both the B{sub s} momentum and the B{sub s} flight distance. The combined result for the D{sub s}-lepton and D{sub s}-hadron samples is: {tau}(B{sub s})=1.54{+-}0.31{+-}0.15 ps where the first error is statistical and the second is systematic. (orig./HSI).

  13. Competition of superconductivity and antiferromagnetism in RNi{sub 2}B{sub 2}C (R = Tm, Dy, Ho, Er)

    Energy Technology Data Exchange (ETDEWEB)

    Sahoo, B.K., E-mail: basanta@iopb.res.in [Govt. College (Auto.), Angul, Odisha 759143 (India); Panda, B.N. [K.K. Junior College, Berhampur, Odisha 760001 (India)

    2015-06-15

    Highlights: • Hamiltonian model to study SC and AFM in RNi{sub 2}B{sub 2}C. • A competition between SC and AFM. - Abstract: The co-existence of superconductivity (SC) and antiferromagnetism (AFM) in RNi{sub 2}B{sub 2}C (R = Tm, Dy, Ho, Er) is reported in this paper. A mean field Hamiltonian model is taken for the system. The order parameters corresponding to SC and AFM are determined and their variation with temperature are studied for these borocarbide superconductors. The interplay of SC and AFM shows BCS type of two gaps in the quasi-particle density of states. Our theoretical study is an attempt to reveal how far the s-wave pairing taken in our model could explain the coexistence properties of SC and AFM in RNi{sub 2}B{sub 2}C.

  14. Carbon ion induced DNA double-strand breaks in melanophore B{sub 16}

    Energy Technology Data Exchange (ETDEWEB)

    Wei Zengquan; Zhou Guangming; Wang Jufang; He Jing; Li Qiang; Li Wenjian; Xie Hongmei; Cai Xichen; Tao Huang; Dang Bingrong; Han Guangwu [Chinese Academy of Sciences, Lanzhou (China). Inst. of Modern Physics; Gao Qingxiang [Lanzhou Univ. (China)

    1997-09-01

    DNA double-strand breaks (DSBs) in melanophore B{sub 16} induced by plateau and extended Bragg peak of 75 MeV/u {sup 12}C{sup 6+} ions were studied by using a technique of inverse pulsed-field gel electrophoresis (PIGE). DNA fragment lengths were distributed in two ranges: the larger in 1.4 Mbp-3.2 Mbp and the smaller in less than 1.2 Mbp. It indicates that distribution of DNA fragments induced by heavy ion irradiation is not stochastic and there probably are sensitive sites to heavy ions in DNA molecules of B{sub 16}. Percentage of DNA released from plug (PR) increased and trended towards a quasi-plateau {proportional_to}85% as dose increased. Content of the larger fragments decreased and flattened with increasing dose while content of the smaller ones increased and trended towards saturation. (orig.)

  15. Electroweak penguins in isospin-violating B{sub s} decays

    Energy Technology Data Exchange (ETDEWEB)

    Hofer, Lars; Scherer, Dominik [Karlsruher Institut fuer Technologie (Germany); Vernazza, Leonardo [Johannes-Gutenberg-Universitaet Mainz (Germany)

    2010-07-01

    During the last decade, experimental data from B{yields}K{pi} decays has caused many discussions about deviations from Standard Model predictions and their possible explanation by New Physics. In particular, models which allow for enhanced electroweak penguins have been investigated in this context since they allow for sizeable isospin-violating effects. We study the consequences of such enhanced electroweak penguins in the purely isospin-violating decays B{sub s}{yields}{phi}{pi} and B{sub s}{yields}{phi}{rho}. The branching fractions of these modes are highly sensitive to New Physics in EW penguins and are thus an interesting topic for LHCb and super-B-factories, complementary to precise B{yields}K{pi} measurements.

  16. Electroweak penguins in isospin-violating B{sub s} decays

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, Dominik; Hofer, Lars [Karlsruhe Institute of Technology - KIT, P.O. Box 3640, 76021 Karlsruhe (Germany); Vernazza, Leonardo [Institut fuer Physik - WA THEP, Johannes-Gutenberg-Universitaet, 55099 Mainz (Germany)

    2010-07-01

    During the last decade, experimental data from B {yields} K {pi} decays has caused many discussions about deviations from Standard Model predictions and their possible explanation by New Physics. In particular, models which allow for enhanced electroweak penguins have been investigated in this context since they allow for sizeable isospin-violating effects. We study the consequences of such enhanced electroweak penguins in the purely isospin-violating decays B{sub s} {yields} {phi} {rho} and B{sub s} {yields} {phi} {pi}. The branching fractions of these modes are highly sensitive to New Physics in EW penguins and are thus an interesting topic for LHCb and Super-B-factories, complementary to precise B {yields} K {pi} measurements. (author)

  17. Radiolysis of cyanocobalamin (vitamin B{sub 12})

    Energy Technology Data Exchange (ETDEWEB)

    Juanchi, X.; Albarran, G.; Negron-Mendoza, A

    2000-03-01

    Research on the radiolysis of vitamins is of considerable interest since these compounds are important nutritional constituents in foods and in dietetic supplements. In spite of these considerations there are few data and very often difficult to compare for the radiolytic behavior of vitamins. In this work we focused our attention on to the study of the radiolysis of cyanocobalamin (vitamin B{sub 12}) in solid state and in aqueous solutions. The procedure was followed by HPLC and UV-spectroscopy. The results obtained in aqueous solutions showed a dependence of the decomposition as a linear function of the dose. The G of decomposition for a 1x10{sup -5} M solution was 3.3. In the solid state the vitamin was very stable towards the irradiation in the conditions used in this study with a G=2.1x10{sup -3}. A study made with Serratia marcescens as a microbiological contaminant showed that at the sterilization dose there is a destruction of the vitamin in aqueous solution. In the solid state the degree of decomposition was 7%. (author)

  18. Disposable pencil graphite electrode modified with peptide nanotubes for Vitamin B{sub 12} analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pala, Betül Bozdoğan [Nanotechnology and Nanomedicine Division, Institute of Science, Hacettepe University, 06800 Ankara (Turkey); Vural, Tayfun [Department of Chemistry, Faculty of Science, Hacettepe University, 06800 Beytepe, Ankara (Turkey); Kuralay, Filiz [Department of Chemistry, Faculty of Science and Arts, Ordu University, 52200 Ordu (Turkey); Çırak, Tamer [Nanotechnology and Nanomedicine Division, Institute of Science, Hacettepe University, 06800 Ankara (Turkey); Bolat, Gülçin; Abacı, Serdar [Department of Chemistry, Faculty of Science, Hacettepe University, 06800 Beytepe, Ankara (Turkey); Denkbaş, Emir Baki, E-mail: denkbas@hacettepe.edu.tr [Department of Chemistry, Faculty of Science, Hacettepe University, 06800 Beytepe, Ankara (Turkey)

    2014-06-01

    In this study, peptide nanostructures from diphenylalanine were synthesized in various solvents with various polarities and characterized with Scanning Electron Microscopy (SEM) and Powder X-ray Diffraction (PXRD) techniques. Formation of peptide nanofibrils, nanovesicles, nanoribbons, and nanotubes was observed in different solvent mediums. In order to investigate the effects of peptide nanotubes (PNT) on electrochemical behavior of disposable pencil graphite electrodes (PGE), electrode surfaces were modified with fabricated peptide nanotubes. Electrochemical activity of the pencil graphite electrode was increased with the deposition of PNTs on the surface. The effects of the solvent type, the peptide nanotube concentration, and the passive adsorption time of peptide nanotubes on pencil graphite electrode were studied. For further electrochemical studies, electrodes were modified for 30 min by immobilizing PNTs, which were prepared in water at 6 mg/mL concentration. Vitamin B{sub 12} analyses were performed by the Square Wave (SW) voltammetry method using modified PGEs. The obtained data showed linearity over the range of 0.2 μM and 9.50 μM Vitamin B{sub 12} concentration with high sensitivity. Results showed that PNT modified PGEs were highly simple, fast, cost effective, and feasible for the electro-analytical determination of Vitamin B{sub 12} in real samples.

  19. Inactivation of cathespin B/sub 1/ by diazomethyl ketones

    Energy Technology Data Exchange (ETDEWEB)

    Leary, R.; Shaw, E.

    1977-12-07

    Benzyloxycarbonyl-phenylalanyl diazomethyl ketone and benzyloxy-carbonyl-phenylalanyl-phenylalanyl diazomethyl ketone, which have been shown to inactivate the thiol protease papain by a mechanism different from that of substrate chloromethyl ketone derivatives, have now been examined as inhibitors of cathepsin B/sub 1/ of beef spleen. The dipeptide derivative irreversibly inactivates this protease rapidly, apparently by affinity labeling.

  20. Thermoluminescence characteristics of gamma irradiated Li{sub 2}B{sub 4}O{sub 7}:Cu nanophosphor

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, Vibha [Department of Physics, Guru Nanak Dev University, Amritsar, Punjab 143005 (India); Singh, Lakhwant, E-mail: lakhwant@yahoo.com [Department of Physics, Guru Nanak Dev University, Amritsar, Punjab 143005 (India); Lochab, S.P. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, PostBox 10502, New Delhi 110067 (India)

    2013-07-21

    Nanocrystals of the Li{sub 2}B{sub 4}O{sub 7}:Cu were synthesized by the combustion method using different concentrations of Cu. X-ray diffraction (XRD) spectra and transmission electron microscopy (TEM) image confirm the nanometric size of synthesized material. The thermal stability of phosphor was obtained by thermogravimetric analysis (TGA). TL characteristics of the synthesized Li{sub 2}B{sub 4}O{sub 7}:Cu material doped with Cu of concentrations 1000 ppm and 2500 ppm were studied. It is observed that Li{sub 2}B{sub 4}O{sub 7}:Cu doped with Cu (both 1000 ppm and 2500 ppm) exhibit a linear response in the range 1×10{sup 0}–5×10{sup 3} Gy of gamma radiations. Finally the trapping parameters associated with the glow peaks were calculated using the glow curve deconvolution (GCD) glow fit method. Fading and reproducibility of phosphors were also studied and it was found that the Li{sub 2}B{sub 4}O{sub 7}:Cu is quite suitable for radiation dosimetry. -- Highlights: • The synthesis of Nanocrystalline Li2B4O7:Cu using the combustion method. • TL properties of samples doped with Cu of concentration 1000 and 2500 ppm are studied. • The trapping parameters of Li2B4O7:Cu nanophosphor are also calculated.

  1. B{sub c}{sup ±} decays into tetraquarks

    Energy Technology Data Exchange (ETDEWEB)

    Ali, A. [DESY Hamburg (Germany); Maiani, L.; Riquer, V. [Sapienza Univ., Roma (Italy). Dipt. di Fisica; INFN Sezione di Roma, Roma (Italy); Polosa, A.D. [Sapienza Univ., Roma (Italy). Dipt. di Fisica; INFN Sezione di Roma, Roma (Italy); CERN, Geneva (Switzerland). Theory Group

    2016-04-15

    The recent observation by the D0 collaboration of a narrow structure X(5568) consisting of four different quark flavors bdus, has not been confirmed by LHCb. More data and dedicated analyses are needed to cover a larger mass range. In the tightly bound diquark model, we estimate the lightest bdus, 0{sup +} tetraquark at a mass of about 5770 MeV, approximately 200 MeV above the reported X(5568), and just 7 MeV below the B anti K threshold. The charged tetraquark is accompanied by I=1 and =0 neutral partners almost degenerate in mass. A bdus, S-wave, 1{sup +} quartet at 5820 MeV is implied as well. In the charm sector, cdus, 0{sup +} and 1{sup +} tetraquarks are predicted at 2365 MeV and 2501 MeV, about 40-50 MeV heavier than D{sub s0}(2317) and D{sub s1}(2460). bdus tetraquarks can be searched in the hadronic debris of a jet initiated by a b. However, some of them may also be produced in B{sub c} decays. The proposed discovery modes of S-wave tetraquarks are B{sub c}→X{sub b0}+π with the subsequent decays X{sub b0}→B{sub s}+π, giving rise to final states such as B{sub s}π{sup +}π{sup 0}. We also emphasize the importance of B{sub c} decays as a source of bound hidden charm tetraquarks, such as B{sub c}→ X(3872)+π.

  2. Comparison of B{sub 2}O{sub 3} and BN deposited by atomic layer deposition for forming ultrashallow dopant regions by solid state diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Consiglio, Steven, E-mail: steve.consiglio@us.tel.com; Clark, Robert D.; O' Meara, David; Wajda, Cory S.; Tapily, Kandabara; Leusink, Gert J. [TEL Technology Center, America, LLC, 255 Fuller Rd., Albany, New York 12203 (United States)

    2016-01-15

    In this study, the authors investigated atomic layer deposition (ALD) of B{sub 2}O{sub 3} and BN for conformal, ultrashallow B doping applications and compared the effect of dopant-containing overlayers on sheet resistance (R{sub s}) and B profiles for both types of films subjected to a drive-in thermal anneal. For the deposition of B{sub 2}O{sub 3}, tris(dimethylamido)borane and O{sub 3} were used as coreactants and for the deposition of BN, BCl{sub 3} and NH{sub 3} were used as coreactants. Due to the extreme air instability of B{sub 2}O{sub 3} films, physical analysis was performed on B{sub 2}O{sub 3} films, which were capped in-situ with ∼30 Å ALD grown Al{sub 2}O{sub 3} layers. For the BN films, in-situ ALD grown Si{sub 3}N{sub 4} capping layers (∼30 Å) were used for comparison. From spectroscopic ellipsometry, a thickness decrease was observed after 1000 °C, 30 s anneal for the B{sub 2}O{sub 3} containing stack with 60 ALD cycles of B{sub 2}O{sub 3}, whereas the BN containing stacks showed negligible thickness decrease after the annealing step, regardless of the number of BN cycles tested. The postanneal reduction in film thickness as well as decrease in R{sub s} for the B{sub 2}O{sub 3} containing stack suggests that the solid state diffusion dopant mechanism is effective, whereas for the BN containing stacks this phenomenon seems to be suppressed. Further clarification of the effectiveness of the B{sub 2}O{sub 3} containing layer compared to the film stacks with BN was evidenced in backside secondary ion mass spectrometry profiling of B atoms. Thus, B{sub 2}O{sub 3} formed by an ALD process and subsequently capped in-situ followed by a drive-in anneal offers promise as a dopant source for ultrashallow doping, whereas the same method using BN seems ineffective. An integrated approach for B{sub 2}O{sub 3} deposition and annealing on a clustered tool also demonstrated controllable R{sub s} reduction without the use of a capping layer.

  3. Studies on influence of aluminium ions on the bioactivity of B{sub 2}O{sub 3}–SiO{sub 2}–P{sub 2}O{sub 5}–Na{sub 2}O–CaO glass system by means of spectroscopic studies

    Energy Technology Data Exchange (ETDEWEB)

    Mohini, G. Jagan; Krishnamacharyulu, N. [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur 522 510, Andhra Pradesh (India); Department of Physics, Andhra Loyola College, Vijayawada 520 008, Andhra Pradesh (India); Sahaya Baskaran, G., E-mail: sbalc@rediffmail.com [Department of Physics, Andhra Loyola College, Vijayawada 520 008, Andhra Pradesh (India); Rao, P. Venkateswara [Physics Department, University of West Indies, Mona Campus, Kingston (Jamaica); Veeraiah, N., E-mail: nvr8@rediffmail.com [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur 522 510, Andhra Pradesh (India)

    2013-12-15

    Bioactive multi component glasses of the composition of 27.4 B{sub 2}O{sub 3}–6.4 SiO{sub 2}–2.5 P{sub 2}O{sub 5}–25.5 Na{sub 2}O–(38.2 − x) CaO: x Al{sub 2}O{sub 3} (x between 0 and 3.2) were synthesized, by melt quenching technique and their bioactivity was investigated as a function of Al{sub 2}O{sub 3} concentration. Initially, optical absorption and infrared spectra were recorded and analyzed in order to have some pre-understanding over structural aspects of the glasses. For understanding the bioactivity, the samples were immersed in simulated body fluid (SBF) solution for prolonged times (∼30 days) and the weight loss measurements were carried out. The spectroscopic studies were repeated on the post immersed samples. From the comparison of the analysis of the spectroscopic data of both pre-immersed and post-immersed samples together with the information on variation of pH value of residual solution as a function of immersion time, it is concluded that the participation of aluminium ions in tetrahedral positions is hindrance for the formation of HA layer and for the bioactivity of the samples.

  4. Thermoluminescence and radioluminescence properties of tissue equivalent Cu-doped Li{sub 2}B{sub 4}O{sub 7} for radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cruz Z, E.; Furetta, C. [UNAM, Instituto de Ciencias Nucleares, Apdo. Postal 70543, 04510 Mexico D. F. (Mexico); Marcazzo, J.; Santiago, M. [Instituto de Fisica Arroyo Seco / UNICEN, Gral. Pinto 399, 7000 Tandil, Buenos Aires (Argentina); Guarneros, C. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Altamira Km 14.5, 896000 Altamira, Tamaulipas (Mexico); Pacio, M. [Benemerita Universidad Autonoma de Puebla, Instituto de Ciencias, Centro de Investigacion en Dispositivos Semiconductores, Av. 14 Sur, 72570 Puebla, Pue. (Mexico); Palomino, R., E-mail: ecruz@nucleares.unam.mx [Benemerita Universidad Autonoma de Puebla, Facultad de Ciencias Fisico-Matematicas, Av. San Claudio y 18 Sur, 72570 Puebla Pue. (Mexico)

    2015-10-15

    Thermoluminescence (Tl) and radioluminescence (Rl) properties of lithium tetraborate (Li{sub 2}B{sub 4}O{sub 7}) doped with different concentration of copper (0.25, 0.5, 1 wt %) under gamma and beta irradiation has been investigated. The feasibility of using this borate in radiation dosimetry at low doses has been evaluated. Tissue equivalent Li{sub 2}B{sub 4}O{sub 7} was prepared by solid state reaction using mixing stoichiometric compositions of lithium carbonate (Li{sub 2}CO{sub 3}) and boric acid (H{sub 3}BO{sub 3}) and a solution of CuCl{sub 2} as dopant. The glow curve, of the most efficient copper doped borate (Li{sub 2}B{sub 4}O{sub 7}:Cu 0.5 wt %), shows a main stable peak centered at 225 degrees C and a second low temperature peak centered at 80 degrees C. The low temperature peak disappears completely after 24 hours of storage in darkness and at room temperature or after an annealing at 120 degrees C for 10 seconds. The main peak of the Li{sub 2}B{sub 4}O{sub 7}:Cu remains constant. The Tl response of Li{sub 2}B{sub 4}O{sub 7}:Cu shows good linearity in the analyzed dose range. The stability and repeatability of Rl signals of the borate have been studied and the Li{sub 2}B{sub 4}O{sub 7}:Cu (0.5 wt %) shown the higher Rl emission and a stable and repetitive response. Results show that Li{sub 2}B{sub 4}O{sub 7}:Cu has prospects to be used in gamma and beta radiation dosimetry. (Author)

  5. Thermodynamic properties of vitamin B{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, A.V., E-mail: knyazevav@gmail.com; Letyanina, I.A.; Plesovskikh, A.S.; Smirnova, N.N.; Knyazeva, S.S.

    2014-01-10

    Graphical abstract: - Highlights: • Temperature dependence of heat capacity of vitamin B{sub 2} has been measured by precision adiabatic vacuum calorimetry. • The thermodynamic functions of the vitamin B{sub 2} have been determined for the range from T → 0 to 322 K. • The energy of combustion of the riboflavin has been measured at 298.15 K. • The enthalpy of combustion Δ{sub c}H° and the thermodynamic parameters Δ{sub f}H°, Δ{sub f}S°, Δ{sub f}G° have been calculated. - Abstract: In the present work temperature dependence of heat capacity of vitamin B{sub 2} (riboflavin) has been measured for the first time in the range from 6 to 322 K by precision adiabatic vacuum calorimetry. Based on the experimental data, the thermodynamic functions of the vitamin B{sub 2}, namely, the heat capacity, enthalpy H°(T) − H°(0), entropy S°(T) − S°(0) and Gibbs function G°(T) − H°(0) have been determined for the range from T → 0 to 322 K. The value of the fractal dimension D in the function of multifractal generalization of Debye's theory of the heat capacity of solids was estimated and the character of heterodynamics of structure was detected. In a calorimeter with a static bomb and an isothermal shield, the energy of combustion of the riboflavin has been measured at 298.15 K. The enthalpy of combustion Δ{sub c}H° and the thermodynamic parameters Δ{sub f}H°, Δ{sub f}S°, Δ{sub f}G° and of reaction of formation of the riboflavin from simple substances at T = 298.15 K and p = 0.1 MPa have been calculated.

  6. Structural and electrical conductivity studies on the solid electrolyte system {sub x}Li2O-(100-x) [0.5B{sub 2}O{sub 3}-0.5 P{sub 2}O{sub 5}] where 20

    Energy Technology Data Exchange (ETDEWEB)

    Padmasree, K. P.; Diaz-Guillen, M. R.; Diaz-Guillen, J. A.; Mendoza, E. M.; Fuentes, A. F. [Cinvestav, unidad Saltillo, Ramos Arizpe, Coahuila (Mexico)]. E-mail: padma512@yahoo.com

    2009-09-15

    Lithium ion conducting glasses have been extensively investigated due to their potential application as solid state amorphous electrolytes in lithium rechargeable batteries. The use of glassy electrolytes in all solid state devices may provide numerous advantages like increased safety, facility of fabrication and miniaturization and having a higher conductivity than those of the crystalline counterparts. In this work, we prepared and studied the Lithium ion conducting glassy solid electrolytes of the composition {sub x}Li{sub 2}O-(1-x)[0.5B{sub 2}O{sub 3} -0.5P{sub 2}O{sub 5}] where 20B{sub 2}O{sub 3} -0.5P{sub 2}O{sub 5}] donde 20

  7. Specific heat of holmium and YNi{sub 2}B{sub 2}C. Criticalbehaviour and superconducting properties; Spezifische Waerme von Holmium und YNi{sub 2}B{sub 2}C. Kritisches Verhalten und supraleitende Eigenschaften

    Energy Technology Data Exchange (ETDEWEB)

    Bekkali, Abdelhakim

    2010-01-04

    Object of the thesis is the study of the specific heat of holmium and YNi{sub 2}B{sub 2}C in the temperature ranges from 50 to 200 KI respectively from 380 mK to 20 K in magnetic fields up to 9 T. In the present thesis the criticalbehaviour of YNi{sub 2}B{sub 2}C and properties of the superconducting state of tne non-magnetic rare-earth nickel borocarbide YNi{sub 2}B{sub 2}C are studied by means of a self-developed measurement apparatur of the specific heat using the quasi-adiabatic heating-pulse method as well as of holmium by means of the relaxation method. In this thesis reliable statements about the critical exponents on monocrystalline holmium could be made. The study on holmium proves that the critical behaviour of the specific heats cannot be described in the framework of the predictions of the chiral universality classes. By means of measurements of the specific heat in this thesis could be confirmed that YNi{sub 2}B{sub 2}C is a multiband superconductor. The positive curvature of the boundary line below T{sub c} in the phase diagram yields a first hint to the many-band character of YNI{sub 2}B{sub 2}C. In the zero-field the electronic specific heat in the superconducting state c{sub es}(T) can be not explained in the framework of the pure BCS theory. At low temperatures a residual contribution by normally conducting electrons could be detected, which hints to a not completely opened energy gap. A possible explanation would be that a band (or several bands) with low charge-carrier concentration not contribute to the superconductivity. This result agrees with de Haas-van Alphen measurements on isostructural superconducting LuNi{sub 2}B{sub 2}C monocrystals, which suggest the many-band character of the superconductivity as well as a vanishing energy gap in one band. The fluctuation behaviour of the specific heat of YNi{sub 2}B{sub 2}C in the neighbourhood of the superconducting-normally conducting transition agrees well with that of the 3D-XY model. [German

  8. Non-isothermal nanocrystallization kinetics study on (Fe{sub 0.8}Ni{sub 0.15}M{sub 0.05}){sub 78}Si{sub 8}B{sub 14} (M = Nb, Ta, W) amorphous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu [School of Materials Science and Engineering, Tongji University, Shanghai 201804 (China); Shanghai Key Lab. of D and A for Metal-Functional Materials, Shanghai 201804 (China); Yan, Biao, E-mail: yanbiao@vip.sina.com [School of Materials Science and Engineering, Tongji University, Shanghai 201804 (China); Shanghai Key Lab. of D and A for Metal-Functional Materials, Shanghai 201804 (China); Yang, Ying [School of Materials Science and Engineering, Tongji University, Shanghai 201804 (China); Shanghai Key Lab. of D and A for Metal-Functional Materials, Shanghai 201804 (China); Wang, Yuxin [School of Materials Science and Engineering, Tongji University, Shanghai 201804 (China); Shanghai Key Lab. of D and A for Metal-Functional Materials, Shanghai 201804 (China); Dept. of Chemical and Materials Engineering, The University of Auckland, PB 92019, Auckland 1142 (New Zealand)

    2013-10-15

    Highlights: •Nb, Ta and W addition affected nucleation and growth mechanism of FeNiSiB alloys. •The alloy with Ta had the best thermal stability compared to the other two alloys. •A process of Fe2B from metastable Fe3B phase existed in the alloy M = Ta. •Nb and W may inhibit formation of metastable Fe3B phase. -- Abstract: The nanocrystallization kinetics of the (Fe{sub 0.8}Ni{sub 0.15}M{sub 0.05}){sub 78}Si{sub 8}B{sub 14} (M = Nb, Ta, W) amorphous alloy was investigated by differential scanning calorimetry (DSC). Kissinger method, Ozawa method and the expended Friedman method were used to calculate and compare the kinetic parameters of the crystallization processes. The nanocrystallization mechanism for the non-isothermal primary crystallization of the amorphous alloys were discussed using Avrami exponent n. Transmission electron microscopy (TEM) studies verified the influence of nanocrystallization mechanism on the microstructure.

  9. Effect of rare earth additions on magnetic properties of Fe{sub 82}Nb{sub 2}B{sub 14}RE{sub 2} (RE = Y, Gd, Tb and Dy) amorphous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Chrobak, A., E-mail: artur.chrobak@us.edu.pl [Institute of Physics, Silesian University, 4 Uniwersytecka, 40-007 Katowice (Poland); Nosenko, V. [G.V. Kurdyumov Institute for Physics of Metals, NAS of Ukraine, Vernadsky ave. 36, 03142 Kyiv (Ukraine); Haneczok, G. [University of Silesia, Institute of Materials Science, 12 Bankowa, 40-007 Katowice (Poland); Boichyshyn, L.; Kotur, B. [Ivan Franko National University of Lviv, Kyryla and Mefodia St. 6, 79005 Lviv (Ukraine); Bajorek, A. [Institute of Physics, Silesian University, 4 Uniwersytecka, 40-007 Katowice (Poland); Zivotsky, O.; Hendrych, A. [Technical University of Ostrava, Institute of Physics, 17. listopadu 15, 708 33 Ostrava-Poruba (Czech Republic)

    2011-10-17

    Highlights: {yields} We studied magnetic properties of Fe{sub 82}Nb{sub 2}B{sub 14}RE{sub 2} (RE=Y,Gd,Tb,Dy) amorphous alloys. {yields} In a comparison with Fe{sub 82}Nb{sub 2}B{sub 14}Y{sub 2} alloy the rare earth editions cause an increase of the Curie temperature and a decrease of magnetic moment per magnetic atom. {yields} Doping of Tb and Dy lead to a strong decrease of magnetic permeability and a formation of low dimensional finger-print magnetic domains. - Abstract: In the present paper the influence of RE alloying additions (Y, Gd, Tb and Dy) on magnetic properties (Curie temperatures, low temperature magnetization, zero field cooling-field cooling curves, domain structure, room temperature magnetostriction and magnetic permeability) of amorphous alloys of type Fe{sub 82}Nb{sub 2}B{sub 14}RE{sub 2} are carefully examined. It was shown that substituting of yttrium atoms by magnetic elements, i.e. Gd, Tb and Dy leads to (i) an increase of the Curie temperature of amorphous phase from 416 K (for Fe{sub 82}Nb{sub 2}B{sub 14}Y{sub 2}) to 450 K (for Fe{sub 82}Nb{sub 2}B{sub 14}Gd{sub 2}) and (ii) a decrease of magnetization in saturation (magnetic field 7 T) which can be explained by antiferromagnetic Fe-RE coupling resulting in a decrease of magnetic moment calculated per magnetic atom from 2.00 {mu}{sub B} for the Fe{sub 82}Nb{sub 2}B{sub 14}Y{sub 2} alloy (Fe in amorphous phase) to 1.51 {mu}{sub B} for the Fe{sub 82}Nb{sub 2}B{sub 14}Tb{sub 2} alloy. It was concluded that Tb and Dy alloying additions introduce a local magnetic anisotropy responsible for significant decrease of initial magnetic permeability (about 5 times in relation to Fe{sub 82}Nb{sub 2}B{sub 14}Y{sub 2} or Fe{sub 82}Nb{sub 2}B{sub 14}Gd{sub 2} alloy), increase of magnetic irreversibility effect measured at 2 K (about 10 times in relation to the same alloys) and appearing of the finger-print magnetic domain regions (not observed for the Fe{sub 82}Nb{sub 2}B{sub 14}Y{sub 2} and Fe{sub 82}Nb

  10. Crystallization of Fe{sub 83}B{sub 17} amorphous alloy by electric pulses produced by a capacitor discharge

    Energy Technology Data Exchange (ETDEWEB)

    Georgarakis, Konstantinos [WPI-AIMR Tohoku University, Sendai (Japan); Institut Polytechnique de Grenoble (INPG), Science et Ingenierie des Materiaux et Procedes (SIMAP-CNRS), Saint-Martin-d' Heres (France); Dudina, Dina V. [Siberian Branch of Russian Academy of Sciences, Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Mali, Vyacheslav I.; Anisimov, Alexander G. [Siberian Branch of Russian Academy of Sciences, Lavrentyev Institute of Hydrodynamics, Novosibirsk (Russian Federation); Bulina, Natalia V. [Siberian Branch of Russian Academy of Sciences, Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk (Russian Federation); Moreira Jorge, Alberto Jr. [Institut Polytechnique de Grenoble (INPG), Science et Ingenierie des Materiaux et Procedes (SIMAP-CNRS), Saint-Martin-d' Heres (France); Federal University of Sao Carlos, Department of Materials Science and Engineering, Sao Carlos, SP (Brazil); Yavari, Alain R. [Institut Polytechnique de Grenoble (INPG), Science et Ingenierie des Materiaux et Procedes (SIMAP-CNRS), Saint-Martin-d' Heres (France)

    2015-09-15

    Heating of conductive materials by electric current is used in many technological processes. Application of electric pulses to metallic glasses induces their fast crystallization, which is an interesting and complex phenomenon. In this work, crystallization of the Fe{sub 83}B{sub 17} amorphous alloy induced by pulses of electric current produced has been studied using X-ray diffraction and transmission electron microscopy. Ribbons of the alloy were directly subjected to single pulses of electric current 250 μs long formed by a capacitor discharge. As the value of ∫I{sup 2}dt was increased from 0.33 to 2.00 A{sup 2} s, different crystallization stages could be observed. The crystallization began through the formation of the nuclei of α-Fe. At high values of ∫I{sup 2}dt, α-Fe and tetragonal and orthorhombic Fe{sub 3}B and Fe{sub 23}B{sub 6} were detected in the crystallized ribbons with crystallites of about 50 nm. Thermal annealing of the ribbons at 600 C for 2 min resulted in the formation of α-Fe and tetragonal Fe{sub 3}B. It was concluded that pulses of electric current produced by a capacitor discharge induced transformation of the Fe{sub 83}B{sub 17} amorphous phase into metastable crystalline products. (orig.)

  11. Microstructures and mechanical properties in B{sub 4}C-CeO{sub 2} ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Sun Shuchen, E-mail: sunsc@smm.neu.edu.cn [School of Materials and Metallurgy, Northeastern University, Shenyang 110004 (China); Sakamoto, Tatsuaki; Nakai, Kiyomichi [Department of Materials Science and Biotechnology, Ehime University, 3Bunkyo-cho, Matsuyama 790-8577 (Japan); Kurishita, Hiroaki [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Kobayashi, Sengo [Department of Materials Science and Biotechnology, Ehime University, 3Bunkyo-cho, Matsuyama 790-8577 (Japan); Xu Jingyu; Cao Hui; Gao Bo; Bianxue; Wu Wenyuan; Tu Ganfeng [School of Materials and Metallurgy, Northeastern University, Shenyang 110004 (China); Matsuda, Seiji [Department of Anatomy and Embryology, Ehime University, Shizugawa, Toon 791-0295 (Japan)

    2011-10-01

    B{sub 4}C-CeO{sub 2} composite ceramics with various concentrations of CeO{sub 2} were fabricated by hot press. The effects of CeO{sub 2} on the microstructures and mechanical properties of the B{sub 4}C-CeO{sub 2} ceramics have been investigated. During hot press, CeB{sub 6} was formed by the reaction between CeO{sub 2} and B{sub 4}C. The B{sub 4}C-CeO{sub 2} ceramics had higher levels of density, fracture toughness, flexural strength and Vickers hardness than those in monolithic B{sub 4}C. The microstructures of the B{sub 4}C-CeO{sub 2} ceramics were observed and analyzed by transmission electron microscopy. In-situ synthesized CeB{sub 6} indicated whisker-like shape and grew along the interface with B{sub 4}C, and different boron carbides with different content of C existed at/around the interface of CeB{sub 6} with B{sub 4}C in the composite ceramics. It made mechanical properties greatly improved.

  12. Microstructural analyses of B{sub 4}C-CeO{sub 2} and B{sub 4}C-La{sub 2}O{sub 3} ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, Tatsuaki, E-mail: sakamoto.tatsuaki@eng.ehime-u.ac.jp [Department of Materials Science and Biotechnology, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577 (Japan); Sun, Shu-Chen [School of Materials and Metallurgy, Northeastern University, Shenyang 110004 (China); Furuno, Tomoya; Kajioka, Michio [Graduate Student of Ehime Univerisity, 3 Bunkyo-cho, Matsuyama 790-8577 (Japan); Nakai, Kiyomichi [Department of Materials Science and Biotechnology, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577 (Japan); Kurishita, Hiroaki [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Kobayashi, Sengo [Department of Materials Science and Biotechnology, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577 (Japan); Wu, Wen-Yuan; Tu, Gan-Feng [School of Materials and Metallurgy, Northeastern University, Shenyang 110004 (China); Matsuda, Seiji [Department of Anatomy and Embryology, Ehime University, Shizugawa, Toon 791-0295 (Japan)

    2011-10-01

    Effects of additions of CeO{sub 2} and La{sub 2}O{sub 3} on microstructure and mechanical properties of B{sub 4}C fabricated under and without hot press have been investigated. Vickers hardness and fracture strength are increased by hot press due to the reduction of porosity because the sintering rate is enhanced. Hardness is increased by the reduction of porosity because crack probably occurs when the hardness is measured due to pore as an initiation point of crack. Hardness increases with increasing additions of CeO{sub 2} and La{sub 2}O{sub 3} because porosity decreases due to the formation of CeB{sub 6} and LaB{sub 6} on the grain boundary of B{sub 4}C, respectively. The borides are formed through reaction between solid phases, which might induce coherent boundary between boride and B{sub 4}C. Such coherency also contributes to strengthening the grain boundary of B{sub 4}C. The addition of CeO{sub 2} enhances the sintering rate more than that of La{sub 2}O{sub 3}, resulting in higher hardness of B{sub 4}C-CeO{sub 2} than that of B{sub 4}C-La{sub 2}O{sub 3}.

  13. Improvement in bronchial squamous metaplasia in smokers treated with folate and vitamin B/sub 12/: report of a preliminary randomized, double-blind intervention trial

    Energy Technology Data Exchange (ETDEWEB)

    Heimburger, D.C.; Alexander, C.B.; Birch, R.; Butterworth, C.E. Jr.; Bailey, W.C.; Krumdieck, C.L.

    1988-03-11

    To test whether changes in folate and vitamin B/sub 12/ nutrition modify the severity of potentially premalignant lesions identified by cytology in sputum samples of smokers, the authors conducted a randomized, controlled prospective intervention trial in smokers with bronchial squamous metaplasia. Seventy-three men with a history of 20 or more pack-years of cigarette smoking who had metaplasia on one or more sputum samples were stratified according to smoking level and randomly assigned to four months' treatment with either placebo or 10 mg of folate plus 500 ..mu..g of hydroxocobalamin. Direct cytological comparison of the two groups after four months showed significantly greater reduction of atypia in the supplemented group. This provides preliminary evidence that atypical bronchial squamous metaplasia may be reduced by supplementation with folate and vitamin B/sub 12/. However, the significance of these findings is tempered by substantial spontaneous variation in sputum cytologies, the small study population, the short duration of the trial, and the supraphysiological doses of folate and B/sub 12/ used. The results should not be construed as pointing to a potential way of preventing lung cancer in individuals who continue to smoke or as supporting self-medication with large doses of folate or B/sub 12/ by smokers.

  14. Evaulation of B{sub 4}C as an ablator material for NIF capsules. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Burnham, A.K.; Alford, C.S.; Makowiecki, D.M.; Dittrich, T.R.; Wallace, R.J.; Honea, E.C.; King, C.M. [Lawrence Livermore National Lab., CA (United States); Steinman, D. [General Atomics, San Diego, CA (United States)

    1997-03-26

    Boron carbide (B{sub 4}C) is examined as a potential fuel container and ablator for implosion capsules on the National Ignition Facility (NIF). A capsule of pure B{sub 4}C encasing a layer of solid DT implodes stably and ignites with anticipated NIF x-ray drives, producing 18 MJ of energy. Thin films of B{sub 4}C were found to be resistant to oxidation and modestly transmitting in the infrared (IR), possibly enabling IR fuel characterization and enhancement for thin permeation barriers but not for full-thickness capsules. Polystyrene mandrels 0.5 mm in diameter were successfully coated with 0.15-2.0 micrometers of B{sub 4}C. Thickness estimated from optical density agreed well with those measured by scanning electron microscopy (SEM). The B{sub 4}C microstructure was columnar but finer than for Be made at the same conditions. B{sub 4}C is a very strong material, with a fiber tensile strength capable of holding NIF fill pressures at room temperature, but it is also very brittle, and microscopic flaws or grain structure may limit the noncryogenic fill pressure. Argon (Ar) permeation rates were measured for a few capsules that had been further coated with 5 micrometers of plasma polymer. The B{sub 4}C coatings tended to crack under tensile load. Some shells filled more slowly than they leaked, suggesting that the cracks open and close under opposite pressure loading. As observed earlier for Ti coatings, 0.15-micrometer layers of B{sub 4}C had better gas retention properties than 2-micrometer layers, possibly because of fewer cracks. Permeation and fill strength issues for capsules with a full ablator thickness of B{sub 4}C are unresolved. 21 refs., 6 figs.

  15. Structural characterization and Mössbauer studies of nanocrystalline Fe{sub 60}Ni{sub 20}Cr{sub 10}B{sub 10} alloy prepared by high energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Slimi, M., E-mail: msrammeh@yahoo.fr [Laboratoire de Chimie Inorganique, UR-11-ES-73, université de Sfax, B.P. 1171, 3000 Sfax (Tunisia); Azabou, M. [Laboratoire de Chimie Inorganique, UR-11-ES-73, université de Sfax, B.P. 1171, 3000 Sfax (Tunisia); Suñol, J.J. [Departament de Fisica, Universitat de Girona, Campus Montilivi, Girona 17071 (Spain); Khitouni, M. [Laboratoire de Chimie Inorganique, UR-11-ES-73, université de Sfax, B.P. 1171, 3000 Sfax (Tunisia); Greneche, J.M. [LUNAM, Institut des Molécules et Matériaux du Mans, IMMM UMR CNRS 6283, Université du Maine, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France)

    2015-11-01

    Nanostructured Fe(Ni,Cr) and NiFe solid state powders were elaborated from elemental powders of Fe, Ni, Cr and B using planetary high-energy ball mill. Scanning electron microscopy (SEM) was employed to examine the morphology of the powdered samples as a function of milling time. The transformations occurring in the material during milling were studied at the atomic scale with the use of X-ray diffraction and {sup 57}Fe Mössbauer spectrometry. The thermal behavior of the milled powders was examined by differential scanning calorimetry (DSC). The results, as well as dissimilarity between calorimetric curves of the powders after 10 and 50 h of milling, indicated the formation of a nanostructured Fe(Ni,Cr) and NiFe solid solutions. - Highlights: • It is a complete study about the alloying process of a nanostructured alloy. • We establish the relation between microstructure and structure defects. • Mössbauer analysis confirms the coexistence of the bcc-Fe(Ni,Cr) and fcc-Ni(Fe) solid solutions.

  16. Boron carbide (B{sub 4}C) coating. Deposition and testing

    Energy Technology Data Exchange (ETDEWEB)

    Azizov, E.; Barsuk, V. [Troitsk Institute for Innovation and Fusion Research (TRINITI), Moscow Region (Russian Federation); Begrambekov, L., E-mail: lbb@plasma.mephi.ru [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation); Buzhinsky, O. [Troitsk Institute for Innovation and Fusion Research (TRINITI), Moscow Region (Russian Federation); Evsin, A.; Gordeev, A.; Grunin, A. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation); Klimov, N. [Troitsk Institute for Innovation and Fusion Research (TRINITI), Moscow Region (Russian Federation); Kurnaev, V. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation); Mazul, I. [Federal State Unitary Interprise Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA Efremov), St-Peterburg (Russian Federation); Otroshchenko, V.; Putric, A. [Troitsk Institute for Innovation and Fusion Research (TRINITI), Moscow Region (Russian Federation); Sadovskiy, Ya.; Shigin, P.; Vergazov, S.; Zakharov, A. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation)

    2015-08-15

    Boron carbide was proposed as a material of in-situ protecting coating for tungsten tiles of ITER divertor. To prove this concept the project including investigation of regimes of plasma deposition of B{sub 4}C coating on tungsten and tests of boron carbide layer in ITER-like is started recently. The paper contends the first results of the project. The results of B{sub 4}C coating irradiation by the plasma pulses of QSPU-T plasma accelerator are presented. The new device capable of B{sub 4}C film deposition on tungsten and testing of the films and materials with ITER-like heat loads and ion- and electron irradiation is described. The results of B{sub 4}C coating deposition and testing of both tungsten substrate and coating are shown and discussed.

  17. Neutron flux measurements with a Li{sub 2}B{sub 4}O{sub 7} crystal

    Energy Technology Data Exchange (ETDEWEB)

    Sangeeta [Crystal Technology Laboratory, TPPED, BARC, Trombay, Mumbai 400085 (India); Chennakesavulu, K. [Crystal Technology Laboratory, TPPED, BARC, Trombay, Mumbai 400085 (India); Desai, D.G. [Crystal Technology Laboratory, TPPED, BARC, Trombay, Mumbai 400085 (India); Sabharwal, S.C. [Crystal Technology Laboratory, TPPED, BARC, Trombay, Mumbai 400085 (India)]. E-mail: sudhirsabharwal@yahoo.co.in; Alex, Mary [Electronics Division, BARC, Trombay, Mumbai 400085 (India); Ghodgaonkar, M.D. [Electronics Division, BARC, Trombay, Mumbai 400085 (India)

    2007-02-11

    The effect of neutron irradiation on a lithium tetraborate (Li{sub 2}B{sub 4}O{sub 7}, LBO) single crystal has been investigated. The crystals of high optical quality are found to be quite stable under high neutron fluence. This study shows that LBO crystals can be used as a proportional counter for neutron fluxes of the order 10{sup 9} cm{sup -2} s{sup -1} and higher. The detectors fabricated were found to have a sensitivity of {approx}3x10{sup -18} A (nv){sup -1}.

  18. Recent results at the SIRa test bench: diffusion properties of carbon graphite and B{sub 4}C targets

    Energy Technology Data Exchange (ETDEWEB)

    Landre-Pellemoine, F.; Barue, C.; Gaubert, G.; Gibouin, S.; Huguet, Y.; Jardin, P.; Kandri-Rody, S.; Lecesne, N.; Leroy, R.; Lewitowicz, M.; Lichtenthaler, R.; Marry, C.; Maunoury, L.; Pacquet, J.Y.; Saint-Laurent, M.G.; Stodel, C.; Rataud, J.P.; Villari, A.C.C. [Grand Accelerateur National d' Ions Lourds (GANIL), 14 - Caen (France); Angelique, J.C.; Orr, N.A. [Laboratoire de Physique Corpusculaire, LPC-ISMRa, CNRS-IN2P3, 14 - Caen (France); Lichtenthaler, R. [IFUSP, Sao Paulo, S.P. (Brazil); Bajeat, O.; Clapier, F.; Ducourtieux, M.; Lau, C.; Obert, J. [Institut de Physique Nucleaire (IN2P3/CNRS), 91 - Orsay (France); Bennett, R. [CLRC, RAL, Chilton Oxon (United Kingdom)

    2000-07-01

    The diffusion properties of graphite targets with 1, 4 and 15 microns microstructure has been measured for He and Ar isotopes. An important enhancement of the diffusion efficiency for the smaller microstructure is observed. A releasing efficiency of the order of 100% was obtained for {sup 6}He (T{sub 1/2} = 806 ms) at a temperature of 1600 K. The diffusion and production properties of He isotopes in a target of B{sub 4}C (Boron Carbide) have also been studied. Yields of 1.5 10{sup 8} pps and 10{sup 6} pps for {sup 6}He and {sup 8}He has been obtained. (authors)

  19. High temperature tribological behaviour of carbon based (B{sub 4}C and DLC) coatings in sliding contact with aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Gharam, A. Abou, E-mail: abougha@uwindsor.c [Mechanical Automotive and Materials Engineering Department, University of Windsor, Windsor, ON, N9B3P4 (Canada); Lukitsch, M.J.; Balogh, M.P. [Chemical Sciences and Materials Systems Laboratory, General Motors R and D Center, 30500 Mound Road, Warren, MI 48090-9055 (United States); Alpas, A.T. [Mechanical Automotive and Materials Engineering Department, University of Windsor, Windsor, ON, N9B3P4 (Canada)

    2010-12-30

    Carbon based coatings, particularly diamond-like carbon (DLC) films are known to resist aluminum adhesion and reduce friction at room temperature. This attractive tribological behaviour is useful for applications such as tool coatings used for aluminum forming and machining. However, for those operations that are performed at elevated temperatures (e.g. hot forming) or that generate frictional heat during contact (e.g. dry machining) the suitable coatings are required to maintain their tribological properties at high temperatures. Candidates for these demanding applications include boron carbide (B{sub 4}C) and DLC coatings. An understanding of the mechanisms of friction, wear and adhesion of carbon based coatings against aluminum alloys at high temperatures will help in designing coatings with improved high temperature tribological properties. With this goal in mind, this study focused on B{sub 4}C and a hydrogenated DLC coatings sliding against a 319 grade cast aluminum alloy by performing pin-on-disk experiments at temperatures up to 400 {sup o}C. Experimental results have shown that the 319 Al/B{sub 4}C tribosystem generated coefficient of friction (COF) values ranging between 0.42 and 0.65, in this temperature range. However, increased amounts of aluminum adhesion were detected in the B{sub 4}C wear tracks at elevated temperatures. Focused ion beam (FIB) milled cross sections of the wear tracks revealed that the coating failed due to shearing along the columnar grain boundaries of the coating. The 319 Al/DLC tribosystem maintained a low COF (0.15-0.06) from room temperature up to 200 {sup o}C. This was followed by an abrupt increase to 0.6 at 400 {sup o}C. The deterioration of friction behaviour at T > 200 {sup o}C was attributed to the exhaustion of hydrogen and hydroxyl passivants on the carbon transfer layer formed on the Al pin.

  20. Search for the B{sub s}{sup 0} → e{sup +}e{sup -} and B{sub d}{sup 0} → e{sup +}e{sup -} decays in Flavor-Changing Z' Model

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, D.; Dharai, C.; Sahoo, S., E-mail: sukadevsahoo@yahoo.com, E-mail: rumidebika@gmail.com [Department of Physics, National Institute of Technology, West Bengal (India)

    2015-10-15

    The precise prediction of the branching ratios of the very rare decays B{sub s}{sup 0} → e{sup +}e{sup -} and B{sub d}{sup 0} → e{sup +}e{sup -} is an important ingredient for high energy research beyond standard model (SM). Recently, the CDF collaboration has reported upper limits for the branching ratios B(B{sub s}{sup 0}→e{sup +}e{sup -})<2.8 x 10{sup -7} and B(B{sub d}{sup 0} →e{sup +}e{sup -}) < 8.3 x 10{sup -8} at 90 % confidence level. These branching ratios are approximately seven orders of magnitude larger than the SMpredictions, providing in thi sway a direction in which the SM could be extended. In this paper, the B{sub s}{sup 0}→e{sup +}e{sup -} and B{sub d}{sup 0} →e{sup +}e{sup -} rare decays in flavor-changing Z' model are studied. Our estimated branching ratios are enhanced from their SM values and provide signals for new physics. (author)

  1. Electron and ion kinetics and anode plasma formation in two applied B/sub r/ field ion diodes

    International Nuclear Information System (INIS)

    Two magnetically insulated ion diodes that utilize a radial applied-B field are described. Both diodes generate an annular beam that is extracted along the diode axis. The first diode operated at 1.2 MV and 600 kA for 25 ns and generated a 300-kA ion beam. The second operated at 300 kV, 100 kA and generated 15 kA of ion current. The first diode was used to study diode performance as a function of inner and outer anode-cathode gaps, the applied-B field, and transmission line current ratios. The second diode was used to study anode plasma formation. The diodes were operated below B/sub crit/, resulting in electron leakage to the anode, especially near the outer cathode. A definition of B/sub crit/ applicable to extraction diodes is given and methods of improving ion production efficiency in these diodes are suggested. The strong correlation of ion production with visible light emission suggests, however, that the electron loss played an important role in anode turn-on. The breakdown of neutral gas desorbed by electron impact is thought to be the anode plasma production mechanism. The grazing incidence leakage electrons affect the breakdown by significantly enhancing space-charge-induced electric fields in the dielectric-filled anode grooves

  2. Study of new complexes of uranium and comba radical. II-Complexes formed in the presence of OH{sup -}, CO{sub 3}H{sup -}, CH{sub 3}-COO{sup -}, and B{sub 4}={sub 7}; Estudio de nuevos complejos entre uranio y el radical CADMBA. II. Complejos formados en presencia de OH{sup -}, CO{sub 3}H, CH{sub 3}-COO{sup -} y B{sub 4}O{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Vera Palomino, V.; Galiano Sedano, J. A.; Parellada Bellod, R.; Bellido Gonzalez, A.

    1975-07-01

    Several complexes extracted with CDMBAC organic solutions from uranium aqueous solutions, in presence of sodium and ammonium hydroxides, are studied. These complexes fit to the general formula: U0{sub 2}(OH){sub n}(CDMBA){sub n}-2 . The uranium extraction in presence of an excess of sodium bicarbonate is also studied. From aqueous solutions of uranyl acetate we have isolated the complex U0{sub 2}(CH{sub 3}-C00){sub n} (CDMBA){sub n}-2. In presence of boric acid and sodium tetraborate an U-CDMBA compound containing boron in its molecule has being obtained by precipitation and liquid-liquid extraction. (Author) 5 refs.

  3. Wear properties of Fe-Cr-C and B{sub 4}C powder coating on AISI 316 stainless steel analyzed by the Taguchi method

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ali Kaya; Ozay, Cetin; Orhan, Ayhan; Buytoz, Soner; Caligulu, Ugur; Yigitturk, Necmettin [Firat Univ., Elazig (Turkey). Faculty of Technical Education

    2014-06-01

    In this study, the plasma arc welded cladding of FeCrC and B{sub 4}C powder mixtures alloyed with 70 wt.-% Cr on the surface of AISI 316 stainless steel was investigated. Application of the Taguchi method revealed respective effects on the abrasive wear resistance of the cladding layer on the stainless steel. The abrasive wear behaviour of the AISI 316 stainless steel surfaces coated with Fe-Cr-C and with 10 wt.-%, 15 wt.-%, 20 wt.-%, and 25 wt.-% B{sub 4}C was investigated by using four loads and four distances for the 220 mesh SiC abrasive. Results were analyzed by variance analysis using ANOVA, and effects of parameters on the wear rate were determined as percentage rate. Furthermore, the error ratio was statistically evaluated. The experimental results were analyzed by the respective analysis of means and variance which is discussed in detail. (orig.)

  4. Radiative leptonic B{sub c}→γℓν{sup -bar} decay in effective field theory beyond leading order

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei, E-mail: wei.wang@sjtu.edu.cn; Zhu, Rui-Lin, E-mail: rlzhu@sjtu.edu.cn [INPAC, Shanghai Key Laboratory for Particle Physics and Cosmology, Department of Physics and Astronomy, Shanghai Jiao Tong University, 200240, Shanghai (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, 100190, Beijing (China)

    2015-08-08

    We study the radiative leptonic B{sub c}→γℓν{sup -bar} decays in nonrelativistic QCD effective field theory, and we explore the contribution from a fast-moving photon. As a result, interactions between the photon and the heavy quarks can be integrated out, resulting in the factorization formula for the decay amplitude. We calculate not only the relevant short-distance coefficients at leading order and next-to-leading order in α{sub s}, but also the nonrelativistic corrections at the order |v|{sup 2} in our analysis. We find that the QCD corrections can significantly decrease the branching ratio, and this is of great importance in extracting the long-distance operator matrix elements of B{sub c}. For phenomenological application, we present our results for the photon energy, lepton energy and lepton-neutrino invariant mass distribution.

  5. Hot pressing of B{sub 4}C/SiC composites

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, F.C.; Turhan, E.; Yesilcubuk, S.A.; Addemir, O. [Ystanbul Technical University, Faculty of Chemistry and Metallurgy, Materials and Metallurgical Engineering Dept., Maslak-Ystanbul (Turkey)

    2005-07-01

    B{sub 4}C/SiC ceramic composites containing 10-20-30 vol % SiC were prepared by hot pressing method. The effect of SiC addition and hot pressing temperature on sintering behaviour and mechanical properties of hot pressed composites were investigated. Microstructures of hot pressed samples were examined by SEM technique. Three different temperatures (2100 deg. C, 2200 deg. C and 2250 deg. C) were used to optimize hot pressing temperature applying 100 MPa pressure under argon atmosphere during the sintering procedure. The highest relative density of 98.44 % was obtained by hot pressing at 2250 deg. C. However, bending strengths of B{sub 4}C/SiC composite samples were lower than monolithic B{sub 4}C in all experimental conditions. (authors)

  6. Photocatalytic characteristics of single phase Fe-doped anatase TiO{sub 2} nanoparticles sensitized with vitamin B{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Gharagozlou, Mehrnaz, E-mail: gharagozlou@icrc.ac.ir [Department of Nanomaterials and Nanotechnology, Institute for Color Science and Technology, Tehran (Iran, Islamic Republic of); Bayati, R. [Intel Corporation, IMO-SC, SC2, Santa Clara, CA 95054 (United States)

    2015-01-15

    Highlights: • Anatase TiO{sub 2}/B{sub 12} hybrid nanostructured catalyst was successfully synthesized by sol–gel technique. • The nanoparticle catalyst was doped with iron at several concentrations. • Nanoparticles were characterized in detail by XRD, Raman, TEM, EDS, and spectroscopy techniques. • The formation mechanism and role of point defects on photocatalytic properties were discussed. • A structure-property-processing correlation was established. - Abstract: We report a processing-structure-property correlation in B{sub 12}-anatase titania hybrid catalysts doped with several concentrations of iron. Our results clearly show that low-level iron doping alters structure, defect content, and photocatalytic characteristics of TiO{sub 2}. XRD and Raman studies revealed formation of a single-phase anatase TiO{sub 2} where no iron based segregation in particular iron oxide, was detected. FT-IR spectra clearly confirmed sensitization of TiO{sub 2} nanoparticles with vitamin B{sub 12}. TEM micrographs and diffraction patterns confirmed crystallization of anatase nanoparticles with a radius of 15–20 nm. Both XRD and Raman signals showed a peak shift and a peak broadening which are surmised to originate from creation of point defects, namely oxygen vacancy and titanium interstitial. The doped samples revealed a narrower band gap as compared to undoped samples. Photocatalytic activity of the samples was assessed through measuring the decomposition rate of rhodamine B. It was found that sensitization with vitamin B{sub 12} and Fe-doping significantly enhances the photocatalytic efficiency of the anatase nanoparticles. We also showed that there is an optimum Fe-doping level where the maximum photocatalytic activity is achieved. The boost of photocatalytic activity was qualitatively understood to originate from a more effective use of the light photons, formation of point defects, which enhance the charge separation, higher carrier mobility.

  7. Photocurrent response of B{sub 12}As{sub 2} crystals to blue light, and its temperature- dependent electrical characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Gul, R., E-mail: rubi786@yahoo.com [Brookhaven National Laboratory, Upton, NY, 11973 (United States); Alabama A& M University, Normal AL, 35762 (United States); Cui, Y.; Bolotnikov, A. E.; Camarda, G. S.; Hossain, A.; Roy, U. N.; Yang, G.; James, R. B. [Brookhaven National Laboratory, Upton, NY, 11973 (United States); Egarievwe, S. U. [Alabama A& M University, Normal AL, 35762 (United States); Edgar, J. H.; Nwagwu, U. [Kansas State University, Manhattan, KS, 66506 (United States)

    2016-02-15

    With the global shortage of {sup 3}He gas, researchers worldwide are looking for alternative materials for detecting neutrons. Among the candidate materials, semiconductors are attractive because of their light weight and ease in handling. Currently, we are looking into the suitability of boron arsenide (B{sub 12}As{sub 2}) for this specific application. As the first step in evaluating the material qualitatively, the photo-response of B{sub 12}As{sub 2} bulk crystals to light with different wavelengths was examined. The crystals showed photocurrent response to a band of 407- and 470- nm blue light. The maximum measured photoresponsivity and the photocurrent density at 0.7 V for 470 nm blue light at room temperature were 0.25 A ⋅ W{sup −1} and 2.47 mA ⋅ cm{sup −2}, respectively. In addition to photo current measurements, the electrical properties as a function of temperature (range: 50-320 K) were measured. Reliable data were obtained for the low-temperature I-V characteristics, the temperature dependence of dark current and its density, and the resistivity variations with temperature in B{sub 12}As{sub 2} bulk crystals. The experiments showed an exponential dependence on temperature for the dark current, current density, and resistivity; these three electrical parameters, respectively, had a variation of a few nA to μA, 1-100 μA ⋅ cm{sup −2} and 7.6x10{sup 5}-7.7x10{sup 3} Ω ⋅ cm, for temperature increasing from 50 K to 320 K. The results from this study reported the first photoresponse and demonstrated that B{sub 12}As{sub 2} is a potential candidate for thermal-neutron detectors.

  8. Electrochemical Polishing Applications and EIS of a Vitamin B{sub 4}-Based Ionic Liquid

    Energy Technology Data Exchange (ETDEWEB)

    Wixtrom, Alex I. [Christopher Newport University, Newport News, VA (United States); Buhler, Jessica E. [Christopher Newport University, Newport News, VA (United States); Reece, Charles E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Abdel-Fattah, Tarek M. [Christopher Newport University, Newport News, VA (United States)

    2013-01-01

    Modern particle accelerators require minimal interior surface roughness for Niobium superconducting radio frequency (SRF) cavities. Polishing of the Nb is currently achieved via electrochemical polishing with concentrated mixtures of sulfuric and hydrofluoric acids. This acid-based approach is effective at reducing the surface roughness to acceptable levels for SRF use, but due to acid-related hazards and extra costs (including safe disposal of used polishing solutions), an acid-free method would be preferable. This study focuses on an alternative electrochemical polishing method for Nb, using a novel ionic liquid solution containing choline chloride, also known as Vitamin B{sub 4} (VB{sub 4}). Potentiostatic electrochemical impedance spectroscopy (EIS) was also performed on the VB4-based system. Nb polished using the VB4-based method was found to have a final surface roughness comparable to that achieved via the acid-based method, as assessed by atomic force microscopy (AFM). These findings indicate that acid-free VB{sub 4}-based electrochemical polishing of Nb represents a promising replacement for acid-based methods of SRF cavity preparation.

  9. Study on feasibility of producing an amorphous surface layer of Fe{sub 49}Cr{sub 18}Mo{sub 7}B{sub 16}C{sub 4}Nb{sub 3} by pulsed Nd:YAG laser surface melting

    Energy Technology Data Exchange (ETDEWEB)

    Mojaver, Reza [Office of Applied Researches and Technology, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of); Mojtahedi, Faezeh [Department of Materials Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of); Shahverdi, Hamid Reza, E-mail: shahverdi@modares.ac.ir [Department of Materials Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of); Torkamany, Mohammad Javad [Iranian National Center for Laser Science and Technology, P.O. Box 14665-576, Tehran (Iran, Islamic Republic of)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer As-cast Fe{sub 49}Cr{sub 18}Mo{sub 7}B{sub 16}C{sub 4}Nb{sub 3} alloy is submitted to pulsed laser surface melting. Black-Right-Pointing-Pointer PLM in various scan speeds was unable to retain complete glassy microstructure. Black-Right-Pointing-Pointer The effects of laser power and scan speed on amorphization have been discussed. Black-Right-Pointing-Pointer A high overlapping factor in PLM can greatly restrict amorphization. Black-Right-Pointing-Pointer Optimization of parameters of PLM to gain a glassy layer of the alloy is not easy. - Abstract: This work aims to investigate whether an amorphous surface layer can be obtained when as-cast Fe{sub 49}Cr{sub 18}Mo{sub 7}B{sub 16}C{sub 4}Nb{sub 3} alloy is submitted to pulsed Nd:YAG laser surface melting. The experiments were conducted in the various laser scanning speeds. The microstructures of laser treated zones were investigated by X-ray diffraction XRD and Field Emission Scanning Electron Microscope (FESEM) and their microhardness were measured, too. The chemical composition of different points of each sample was analyzed by energy-dispersive X-ray spectroscopy EDS. Although the estimated cooling rates in surface layers were higher than the required cooling rate to achieve full amorphization, but the present experiments were unable to retain complete glassy microstructure on surface and a mixture of amorphous (low volume fraction) and ultrafine grained phases were produced in surface of samples. Based on the findings, it was understood that the overlapping of successive pulses and element redistributions occurred in pulsed laser melting could severely restrict amorphization. The influence of laser scan speed and laser power on heat input, melting ratio, compositional changes and cracking in laser treated zone were discussed separately. It is suggested that the limited range of laser variables in pulsed Nd:YAG laser melting may help to produce a sound amorphous phase of

  10. Effect of the surface preparation techniques on the EBSD analysis of a friction stir welded AA1100-B{sub 4}C metal matrix composite

    Energy Technology Data Exchange (ETDEWEB)

    Guo, J., E-mail: junfeng.guo@cnrc-nrc.gc.ca [University of Quebec at Chicoutimi, Chicoutimi (QC), G7H 2B1 (Canada); Aluminium Technology Centre, National Research Council Canada, Chicoutimi (QC), G7H 8C3 (Canada); Amira, S.; Gougeon, P. [Aluminium Technology Centre, National Research Council Canada, Chicoutimi (QC), G7H 8C3 (Canada); Chen, X.-G. [University of Quebec at Chicoutimi, Chicoutimi (QC), G7H 2B1 (Canada)

    2011-09-15

    Aluminum based metal matrix composites (MMCs) have been used in various automobile, aerospace and military industries. Yet characterization of the microstructure in these materials remains a challenge. In the present work, the grain structure in the matrix of B{sub 4}C particulate reinforced MMCs and their friction stir welds is characterized by using optical metallography and the electron backscatter diffraction (EBSD) technique. Optical metallography can partially reveal the grain structure in the matrix of AA1100-16 vol.% B{sub 4}C composite. The EBSD technique has been successfully applied to characterize the grain structure in the AA1100-16 vol.% B{sub 4}C friction stir welds, which provides a powerful tool to follow the microstructural evolution of MMC materials during friction stir welding (FSW). Both mechanical polishing and ion beam polishing are used for the EBSD sample preparation. The effect of the sample preparation on the EBSD data acquisition quality is studied. Some typical examples, such as the identification of grains and subgrains, grain size distribution, deformation fields and the texture components are given. - Highlights: {yields} EBSD has been used to characterize the grain structure of Al-B{sub 4}C MMCs. {yields} Mechanical and ion beam polishing are compared for EBSD sample preparation of MMCs. {yields} EBSD shows great advantages over optical microscopy for microtexture analysis of MMCs.

  11. Effect of gamma irradiation on the thiamine, riboflavin and vitamin B{sub 6} content in two varieties of Brazilian beans

    Energy Technology Data Exchange (ETDEWEB)

    Villavicencio, A.L.C.H. E-mail: villavic@net.ipen.br; Mancini-Filho, J. E-mail: jmancini@usp.br; Delincee, H. E-mail: henry.delincee@bfe.uni-karlsruhe.de; Bognar, A

    2000-03-01

    The effect of {sup 60}Co gamma rays on the content of several B-vitamins in two varieties of Brazilian beans has been studied. Carioca (Phaseolus vulgaris L. var. Carioca) and Macacar beans (Vigna unguiculata L. Walp, var. Macacar) were irradiated at doses of 0, 0.5, 1.0, 2.5, 5.0 and 10 kGy, and subsequently stored at ambient temperature for 6 months. The content of vitamin B{sub 1}, B{sub 2} and B{sub 6} was analysed by HPLC. In addition, the optimum cooking time was established for each dose and bean variety. A taste panel evaluated sensory properties. Only slight changes were measured for thiamine and riboflavin, whereas a dose-dependent decrease was noted for pyridoxine, which, however, was significant only at the highest doses of 5 and 10 kGy. Cooking time was considerably reduced with increasing radiation dose, but accompanied by a loss of the sensory quality. However, at the disinfestation dose up to 1 kGy, acceptable ratings were obtained for the sensory evaluation. In conclusion, for insect disinfestation of Brazilian beans radiation processing is a promising technology.

  12. The design, microstructure and tensile properties of B{sub 4}C particulate reinforced 6061Al neutron absorber composites

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.S. [School of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Wang, W.X., E-mail: Wangwenxian@tyut.edu.cn [School of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Li, Y.L.; Zhang, P. [School of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Nie, H.H. [Shanxi Coal-Mining Administrators College, Taiyuan 030024 (China); Wu, Q.C. [School of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China)

    2015-05-25

    Highlights: • B{sub 4}C/Al composites for neutron shielding were designed by MCNP program. • B{sub 4}C/Al composite were fabricated by vacuum hot pressing followed by hot rolling. • The properties can be enhanced by vacuum hot pressing followed by hot rolling. - Abstract: Based on the Monte Carlo Particle transport program MCNP, a novel boron carbide particulate reinforced 6061Al composite for neutron shielding (B{sub 4}C/6061Al NACs) with high strength and low density was designed. The NACs with four volume fractions (10%, 20%, 30% and 40%) were successfully fabricated by vacuum hot pressing followed by hot rolling (VPHR) in atmospheric environments. The calculation results indicated that the neutron transmission ratio decreased with the increasing of B{sub 4}C content and the thickness of plates. B{sub 4}C particle is uniformly distributed in the matrix, exhibiting the good bonding in interface. The phases of neutron absorbers were mainly B{sub 4}C and Al, and a spot of AlB{sub 2} and Al{sub 3}BC. The grain of the matrix was refined and the dislocation was formed around the particles. With increasing the B{sub 4}C content, the particles gathered, breakage appeared, and the tensile strength of composite first increased and then decreased. The failure mode of B{sub 4}C/6061Al NACs included: the interfacial debonding and the cleavage fracture of particles.

  13. Heat and charge transport in YNi{sub 2}B{sub 2}C and HoNi{sub 2}B{sub 2}C single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M; Gladun, A; Kreyssig, A [Institut fuer Festkoerperphysik, Technische Universitaet Dresden, D-01062 Dresden (Germany); Wosnitza, J [Hochfeld-Magnetlabor Dresden (HLD), Forschungszentrum Dresden-Rossendorf, D-01314 Dresden (Germany); Petzold, V; Rosner, H [Max-Planck-Institut fuer Chemische Physik fester Stoffe, D-01187 Dresden (Germany); Behr, G; Souptel, D; Mueller, K-H; Drechsler, S-L; Fuchs, G [Leibniz-Institut fuer Festkoerper- und Werkstoffforschung Dresden (IFW), D-01171 Dresden (Germany)], E-mail: M.Schneider@ifw-dresden.de, E-mail: G.Fuchs@ifw-dresden.de

    2008-04-30

    For a systematic investigation of the heat- and charge-transport properties of YNi{sub 2}B{sub 2}C and HoNi{sub 2}B{sub 2}C, single-crystal measurements of the electrical resistivity, the thermal conductivity, and the thermoelectric power were performed on the same samples. For HoNi{sub 2}B{sub 2}C, a local maximum of the Lorenz number at 20 K is evidently connected with the occurrence of magnetic fluctuations well above the ordering temperature. For the in-plane thermal conductivity, a kink near the superconducting transition was observed, consistent with an anisotropic gap or a multiband description. For both investigated borocarbides, the electrical resistance is isotropic. In contrast, the thermal conductivity shows a pronounced anisotropy. The thermoelectric power exhibits a minor anisotropy and can be well described by electron-diffusion and phonon-drag contributions over a wide temperature range. Based on an analysis of full-potential local-orbital calculations, a strong influence of the boron z position on the thermoelectric power has been revealed.

  14. High-resolution crystal structures of the solubilized domain of porcine cytochrome b{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Yu [Quantum Beam Science Center, Japan Atomic Energy Agency, 2-4 Shirakata, Tokai, Ibaraki 319-1195 (Japan); Kimura, Shigenobu [Faculty of Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511 (Japan); Tamada, Taro, E-mail: tamada.taro@jaea.go.jp [Quantum Beam Science Center, Japan Atomic Energy Agency, 2-4 Shirakata, Tokai, Ibaraki 319-1195 (Japan)

    2015-06-30

    Crystal structures of the solubilized domain of cytochrome b{sub 5} from porcine liver were determined at sub-angstrom resolution in two crystal forms for both the oxidized and reduced states. The high-resolution structures provided information about the factors that are important for regulating the electronic properties of the haem group of cytochrome b{sub 5}. Mammalian microsomal cytochrome b{sub 5} has multiple electron-transfer partners that function in various electron-transfer reactions. Four crystal structures of the solubilized haem-binding domain of cytochrome b{sub 5} from porcine liver were determined at sub-angstrom resolution (0.76–0.95 Å) in two crystal forms for both the oxidized and reduced states. The high-resolution structures clearly displayed the electron density of H atoms in some amino-acid residues. Unrestrained refinement of bond lengths revealed that the protonation states of the haem propionate group may be involved in regulation of the haem redox properties. The haem Fe coordination geometry did not show significant differences between the oxidized and reduced structures. However, structural differences between the oxidized and reduced states were observed in the hydrogen-bond network around the axial ligand His68. The hydrogen-bond network could be involved in regulating the redox states of the haem group.

  15. Crystal structure and magnetization of a Co{sub 3}B{sub 2}O{sub 6} single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Kazak, N. V.; Platunov, M. S., E-mail: platunov@iph.krasn.ru [Russian Academy of Sciences, Kirensky Institute of Physics, Siberian Branch (Russian Federation); Ivanova, N. B. [Siberian Federal University (Russian Federation); Knyazev, Yu. V.; Bezmaternykh, L. N.; Eremin, E. V.; Vasil' ev, A. D.; Bayukov, O. A.; Ovchinnikov, S. G.; Velikanov, D. A. [Russian Academy of Sciences, Kirensky Institute of Physics, Siberian Branch (Russian Federation); Zubavichus, Ya. V. [Russian Research Centre Kurchatov Institute (Russian Federation)

    2013-07-15

    The crystal structure and magnetic properties of Co{sub 3}B{sub 2}O{sub 6} single crystals are studied. Orthorhombic symmetry with space group Pnnm is detected at room temperature. The measurements of static magnetization and dynamic magnetic susceptibility reveal two magnetic anomalies at T{sub 1} = 33 K and T{sub 2} = 10 K and an easy-axis magnetic anisotropy. The effective magnetic moment indicates a high-spin state of the Co{sup 2+} ion. A spin-flop transition is found at low temperatures and H{sub sf} = 23 kOe. EXAFS spectra of the K-edge absorption of Co are recorded at various temperatures, the temperature-induced changes in the parameters of the local environment of cobalt are analyzed, and the effective Co-Co and Co-O distances are determined. The magnetic interactions in the crystal are analyzed in terms of an indirect coupling model.

  16. Direct imaging of structural heterogeneity of the melt-spun Fe{sub 85.2}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 0.8} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Kazuhisa, E-mail: ksato@imr.tohoku.ac.jp; Takenaka, Kana; Makino, Akihiro [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Hirotsu, Yoshihiko [Institute of Scientific and Industrial Research, Osaka University, Ibaraki 567-0047 (Japan)

    2015-06-15

    A structural heterogeneity of the melt-spun Fe{sub 85.2}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 0.8} alloy has been studied by spherical aberration (C{sub s}) corrected high-resolution transmission electron microscopy. Hollow-cone illumination imaging revealed that the density of coherent scattering regions in the as-quenched Fe{sub 85.2}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 0.8} alloy is much higher than that in the Fe{sub 76}Si{sub 9}B{sub 10}P{sub 5} bulk metallic glass. According to the C{sub s}-corrected TEM, crystalline atomic clusters, typically of ∼1 nm in diameter, are densely distributed in an amorphous matrix of Fe{sub 85.2}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 0.8} alloy. Observation of four-fold and six-fold atomic arrangements of these clusters implies existence of Fe clusters with the body centered cubic structure. These Fe clusters must be responsible for the formation of ultrahigh-density α-Fe nanocrystals produced by post-annealing.

  17. Need for a sufficient number of low level sera in comparisons of different serum vitamin B/sub 12/ assays

    Energy Technology Data Exchange (ETDEWEB)

    Gijzen, A.H.J. (De Wever Hospital, Heerlen (Netherlands)); de Kock, H.W. (Sophia Hospital, Zwolle (Netherlands)); Meulendijk, P.N. (St. Elisabeth Hospital, Arnhem (Netherlands)); Schmidt, N.A. (Medical Laboratories, Breda (Netherlands)); Schopman, W. (Bergwegziekenhuis, Rotterdam (Netherlands)); Tertoolen, J.F.W. (Laboratory for Nuclear Medicine ' ' Voorburg' ' , Vught (Netherlands)); Voogd, C.E. (Rijksinstituut voor de Volksgezondheid, Bilthoven (Netherlands))

    1983-01-24

    Eight radiochemical methods for the assay of vitamin B/sub 12/ in serum were compared with the microbiological assay with Lactobacillus leichmannii ATCC 7830 using 198 individual sera of patients. There was a good agreement between the results of most samples with some kits and the microbiological assay. However, especially in the sera of vitamin B/sub 12/-deficient patients large discrepancies between the results could occur. These variations were due to both the kits used and the performance of the assays in different laboratories. A sufficient number of non-pooled sera of vitamin B/sub 12/-deficient patients should be included in investigations to validate radiochemical methods.

  18. Electronic structure, Fermi surface and optical properties of metallic compound Be{sub 8}(B{sub 48})B{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Reshak, A.H. [Institute of Complex Systems, FFPW, CENAKVA, University of South Bohemia in CB, Nove Hrady 37333 (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia); Azam, Sikander, E-mail: sikander.physicst@gmail.com [Institute of Complex Systems, FFPW, CENAKVA, University of South Bohemia in CB, Nove Hrady 37333 (Czech Republic); Alahmed, Z.A. [Department of Physics and Astronomy, King Saud University, Riyadh 11451 (Saudi Arabia); Chyský, Jan [Department of Instrumentation and Control Engineering, Faculty of Mechanical Engineering, CTU in Prague, Technicka 4, 166 07 Prague 6 (Czech Republic)

    2014-02-15

    The band structure, density of states, electronic charge density, Fermi surface and optical properties for B{sub 8}(Be{sub 48})B{sub 2} compound has been investigated in the support of density functional theory (DFT). The atomic positions of B{sub 8}(Be{sub 48})B{sub 2} compound were optimized by minimization of the forces acting on the atoms using the full potential linear augmented plane wave (FPLAPW) method. We have employed the local density approximation (LDA), generalized gradient approximation (GGA) and Engal-Vosko GGA (EVGGA) to indulgence the exchange correlation potential by solving Kohn–Sham equations. The result shows that the compound is metallic with sturdy hybridization near the Fermi energy level (E{sub F}). The density of states at Fermi energy, N(E{sub F}), is determined by the overlaping between B-p, B-s and Be-s states. This overlaping is strong enough indicating metallic origin with different values of N(E{sub F}). These values are 16.4, 16.27 and 14.89 states/eV, and the corresponding bare linear low-temperature electronic specific heat coefficient (γ) is found to be 2.84, 2.82 and 2.58 mJ/mol K{sup 2} for EVGGA, GGA and LDA respectively. There exists a strong hybridization between B-s and B-p states, also between B-s and Be-p states around the Fermi level. The Fermi surface is composed of three sheets. These sheets consist of set of holes and electrons. The bonding features of the compounds are analyzed using the electronic charge density in the (101 and −101) crystallographic planes and also the analyzing of charge density shows covalent bonding between B and B. The linear optical properties are also deliberated and discussed in particulars. - Highlights: • The compound is metallic. • The density of states at the Fermi energy is calculated. • The bare linear low-temperature electronic specific heat coefficient is obtained. • Fermi surface is composed of three sheets. • The bonding features are analyzed using the electronic

  19. Analyzing B{sub s} - anti B{sub s} mixing. Non-perturbative contributions to bag parameters from sum rules

    Energy Technology Data Exchange (ETDEWEB)

    Mannel, T. [Siegen Univ. (Germany). FB 7, Theoretische Physik; Pecjak, B.D. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Pivovarov, A.A. [Siegen Univ. (Germany). FB 7, Theoretische Physik]|[Russian Academy of Sciecnes, Moscow (Russian Federation). Inst. for Nuclear Research

    2007-03-15

    We use QCD sum rules to compute matrix elements of the {delta}B=2 operators appearing in the heavy-quark expansion of the width difference of the B{sub s} mass eigenstates. Our analysis includes the leading-order operators Q and Q{sub S}, as well as the subleading operators R{sub 2} and R{sub 3}, which appear at next-to-leading order in the 1/m{sub b} expansion. We conclude that the violation of the factorization approximation for these matrix elements due to non-perturbative vacuum condensates is as low as 1-2%. (orig.)

  20. Structure refinement and one-center luminescence of Eu{sup 3+} activated ZnBi{sub 2}B{sub 2}O{sub 7} under UV excitation

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Liwei; Zhang, Fangxin [The MOE Key Laboratory of Weak-Light Nonlinear Photonics, School of Physics, Nankai University, Tianjin 300071 (China); Wu, Li, E-mail: lwu@nankai.edu.cn [The MOE Key Laboratory of Weak-Light Nonlinear Photonics, School of Physics, Nankai University, Tianjin 300071 (China); Yi, Huan [The MOE Key Laboratory of Weak-Light Nonlinear Photonics, School of Physics, Nankai University, Tianjin 300071 (China); Wang, Hongrun [Institute of Photo-electronic Thin Film Devices and Technology, Tianjin Key Laboratory of Photo-electronic Thin Film Devices and Technology, and Key Laboratory of Optoelectronic Information Science and Technology, Ministry of Education, Nankai University, Tianjin 300071 (China); Zhang, Yi, E-mail: yizhang@nankai.edu.cn [Institute of Photo-electronic Thin Film Devices and Technology, Tianjin Key Laboratory of Photo-electronic Thin Film Devices and Technology, and Key Laboratory of Optoelectronic Information Science and Technology, Ministry of Education, Nankai University, Tianjin 300071 (China); Kong, Yongfa; Xu, Jingjun [The MOE Key Laboratory of Weak-Light Nonlinear Photonics, School of Physics, Nankai University, Tianjin 300071 (China)

    2015-11-05

    A series of Eu{sup 3+}-activated red phosphors ZnBi{sub 2}B{sub 2}O{sub 7}:xEu{sup 3+} were synthesized by high temperature solid-state reaction method. Rietveld refinement on the powder X-ray diffraction (XRD) data was performed to study the local crystal environment of Eu{sup 3+} in ZnBi{sub 2}B{sub 2}O{sub 7} host. The refinement results disclose that the doped Eu{sup 3+} do not change the host structure. Although two different cation sites are available, the doped Eu{sup 3+} is inclined to occupy Zn site instead of Bi site. This indicates that there is only one luminescent center when Eu{sup 3+} is doped into ZnBi{sub 2}B{sub 2}O{sub 7} phosphor, which is further confirmed by the luminescence properties of ZnBi{sub 2}B{sub 2}O{sub 7}:xEu{sup 3+}. The influences of the doping concentration and the excitation wavelength on the one-center luminescence of Eu{sup 3+} in ZnBi{sub 2}B{sub 2}O{sub 7} are discussed along with the decay characteristics. Based on the temperature-dependent PL spectra, the fast decrease of emission intensity with the increase of temperature is due to the non-radiative relaxation. - Highlights: • New red-emitting ZnBi{sub 2}B{sub 2}O{sub 7}:xEu{sup 3+} phosphors excited by near ultraviolet light were synthesized. • The doped Eu{sup 3+} prefers to occupy Zn{sup 2+} site and there is only one-center luminescence of Eu{sup 3+} in ZnBi{sub 2}B{sub 2}O{sub 7} host. • CIE coordinates are very much closer to that of standard red light (0.67, 0.33)

  1. Structure elucidation and toxicity analyses of the radiolytic products of aflatoxin B{sub 1} in methanol-water solution

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Feng [Institute of Agro-food Science and Technology of Chinese Academy of Agricultural Sciences, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Key Opening Laboratory of Agricultural Products Processing and Quality Control, Ministry of Agriculture, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Graduate School of Chinese Academy of Agricultural Sciences, 12th Zhongguancun South Road, Hai Dian District, Beijing 100081 (China); Xie, Fang [Institute of Agro-food Science and Technology of Chinese Academy of Agricultural Sciences, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Key Opening Laboratory of Agricultural Products Processing and Quality Control, Ministry of Agriculture, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Xue, Xiaofeng [Bee Research Institute of Chinese Academy of Agricultural Sciences, 1st Xiangshan North Ditch, Hai Dian District, Beijing 100093 (China); Wang, Zhidong; Fan, Bei [Institute of Agro-food Science and Technology of Chinese Academy of Agricultural Sciences, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Key Opening Laboratory of Agricultural Products Processing and Quality Control, Ministry of Agriculture, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Ha, Yiming, E-mail: wxfay2011@hotmail.com [Institute of Agro-food Science and Technology of Chinese Academy of Agricultural Sciences, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Key Opening Laboratory of Agricultural Products Processing and Quality Control, Ministry of Agriculture, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China)

    2011-09-15

    Highlights: {yields} Radiolytic products of aflatoxin B{sub 1} were produced under gamma irradiation. {yields} Seven key radiolytic products were structure-elucidated. {yields} Free-radical species in radiolytic solution resulted in the formation of products. {yields} Based on the structure-activity relationship analysis, the toxicity of radiolytic products was significantly reduced compared with that of AFB{sub 1}. {yields} The addition reaction on furan ring double bond was the reason for the reduced toxicity. - Abstract: The identification of the radiolytic products of mycotoxins is a key issue in the feasibility study of gamma ray radiation detoxification. Methanol-water solution (60:40, v/v) spiked with aflatoxin B{sub 1} (AFB{sub 1}; 20 mg L{sup -1}) was irradiated with Co{sup 60} gamma ray to generate radiolytic products. Liquid chromatography-quadruple time-of-flight mass spectrometry was applied to identify the radiolytic products of AFB{sub 1}. Accurate mass and proposed molecular formulas with a high-matching property of more than 20 radiolytic products were obtained. Seven key radiolytic products were proposed based on the molecular formulas and tandem mass spectrometry spectra. The analyses of toxicity and formation pathways were proposed based on the structure of the radiolytic products. The addition reaction caused by the free-radical species in the methanol-water solution resulted in the formation of most radiolytic products. Based on the structure-activity relationship analysis, the toxicity of radiolytic products was significantly reduced compared with that of AFB{sub 1} because of the addition reaction that occurred on the double bond in the terminal furan ring. For this reason, gamma irradiation is deemed an effective tool for the detoxification of AFB{sub 1}.

  2. Flight to Mars and radiation defects in Li{sub 2}B{sub 4}O{sub 7} and KTiOPO{sub 4} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Grachev, V.; Malovichko, G.; Pankratov, V.; Rust, T. [Physics Department, Montana State University, Bozeman, MT 59717 (United States); Burak, Ya. [Institute of Physical Optics, Lviv 79005 (Ukraine)

    2007-03-15

    Solar, space, laser and nuclear reactor radiations lead to the appearance of defects in complex oxides and to inevitable performance degradation of devices based on these materials. Since many radiation defects are paramagnetic ones, the electron paramagnetic resonance, EPR is one of the most suitable method for their study. Results of optical and EPR study of defects in as grown and irradiated Li{sub 2}B{sub 4}O{sub 7} and KTiOPO{sub 4} crystals are presented. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Masses and electromagnetic transitions of the B{sub c} mesons

    Energy Technology Data Exchange (ETDEWEB)

    Devlani, N.; Kher, V. [The M S University of Baroda, Applied Physics Department, Polytechnic, Gujarat (India); Rai, A.K. [Sardar Vallabhbhai National Institute of Technology, Department of Applied Physics, Gujarat (India)

    2014-10-15

    The mass spectra and decay properties of the B{sub c}(c anti b) meson are investigated in the framework of the phenomenological quark anti-quark potential (Coulomb plus power) model consisting of relativistic corrections to the kinetic-energy term as well as relativistic corrections to the quark antiquark potential at O(1/m) using the Gaussian wave function. The spin-spin, spin-orbit and tensor interactions are employed to obtain the pseudoscalar and vector meson masses incorporating the effect of mixing. The decay constants (f{sub P/V}) with and without QCD correction are computed using the wave function at the origin. The electromagnetic transition rates are also calculated in this scheme. Our predictions for the B{sub c} meson are in good agreement with experimental results as well as other theoretical models. (orig.)

  4. B{sub K}-parameter from N{sub f}=2 twisted mass lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Constantinou, M. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Dimopoulos, P. [Roma Univ. (Italy). Dipt. di Fisica; Frezzotti, R. [Roma ' ' Tor Vergata' ' Univ. (Italy). Dipt. di Fisica; INFN, Rome (IT). Dipt. di Fisica] (and others)

    2011-01-07

    We present an unquenched N{sub f} = 2 lattice computation of the B{sub K} parameter which controls K{sup 0}- anti K{sup 0} oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence quarks of both the maximally twisted and the Osterwalder-Seiler variety. Suitable combinations of these two kinds of valence quarks lead to a lattice definition of the B{sub K} parameter which is both multiplicatively renormalizable and O(a) improved. Employing the non-perturbative RI-MOM scheme, in the continuum limit and at the physical value of the pion mass we get B{sup RGI}{sub K}=0.729{+-}0.030, a number well in line with the existing quenched and unquenched determinations. (orig.)

  5. Thermodynamic properties and low-temperature X-ray diffraction of vitamin B{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, A.V., E-mail: knyazevav@gmail.com; Smirnova, N.N.; Shipilova, A.S.; Shushunov, A.N.; Gusarova, E.V; Knyazeva, S.S.

    2015-03-20

    Highlights: • Temperature dependence of heat capacity of vitamin B{sub 3} has been measured by precision adiabatic vacuum calorimetry. • The thermodynamic functions of the vitamin B{sub 3} have been determined for the range from T → 0 to 346 K. • The thermodynamic analysis of reactions involving nicotinic acid was made. • The low-temperature X-ray diffraction was used for the determination of coefficients of thermal expansion. - Abstract: In the present work temperature dependence of heat capacity of vitamin B{sub 3} (nicotinic acid) has been measured for the first time in the range from 5 to 346 K by precision adiabatic vacuum calorimetry. Based on the experimental data, the thermodynamic functions of the vitamin B{sub 3}, namely, the heat capacity, enthalpy H°(T) – H°(0), entropy S°(T) – S°(0) and Gibbs function G°(T) – H°(0) have been determined for the range from T → 0 to 343 K. The value of the fractal dimension D in the function of multifractal generalization of Debye’s theory of the heat capacity of solids was estimated and the character of heterodynamics of structure was detected. The thermodynamic parameters Δ{sub f}S°, Δ{sub f}G° at T = 298.15 K and p = 0.1 MPa have been calculated. The thermodynamic analysis of reactions involving nicotinic acid was made. The low-temperature X-ray diffraction was used for the determination of coefficients of thermal expansion.

  6. Dipstick based immunochemiluminescence biosensor for the analysis of vitamin B{sub 12} in energy drinks: A novel approach

    Energy Technology Data Exchange (ETDEWEB)

    Selvakumar, L.S. [Fermentation Technology and Bioengineering Department, Central Food Technological Research Institute (a constituent laboratory of the Council of Scientific and Industrial Research, CSIR), Mysore 570020, Karnataka (India); Thakur, M.S., E-mail: msthakur@cftri.res.in [Fermentation Technology and Bioengineering Department, Central Food Technological Research Institute (a constituent laboratory of the Council of Scientific and Industrial Research, CSIR), Mysore 570020, Karnataka (India)

    2012-04-13

    Graphical abstract: (a) Schematic representation of immunochemiluminescence based dipstick technique for detection of vitamin B{sub 12}. (b) Enzymatic dephosphorylation of dioxetane by alkaline phosphatase. Highlights: Black-Right-Pointing-Pointer Dipstick based immunochemiluminescence biosensor proposed for vitamin B{sub 12} analysis. Black-Right-Pointing-Pointer The limit of detection of vitamin B{sub 12} is 1 ng mL{sup -1} and applied in energy drinks. Black-Right-Pointing-Pointer Chemiluminescence generated was inversely proportional to vitamin B{sub 12} concentration. Black-Right-Pointing-Pointer Chemiluminescence analytical procedure was compared with ELISA. Black-Right-Pointing-Pointer Alkaline phosphatase was stable chemiluminescent enzyme than Horse Radish Peroxidase. - Abstract: In this article, we describe a dipstick based immunochemiluminescence (immuno-CL) biosensor for the detection of vitamin B{sub 12} in energy drinks. The method is a direct competitive type format involving the immobilization of vitamin B{sub 12} antibody on nitrocellulose membrane (NC) followed by treatment with vitamin B{sub 12} and vitamin B{sub 12}-alkaline phosphatase conjugate to facilitate the competitive binding. The dipstick was further treated with substrate disodium 2-chloro-5-(4-methoxyspiro {l_brace}1,2-dioxetane-3,2 Cent-Sign -(5 Cent-Sign -chloro)tricyclo[3.3.1.13,7]decan{r_brace}-4-yl)-1-phenyl phosphate (CDP-Star) to generate chemiluminescence (CL). The number of photons generated was inversely proportional to the vitamin B{sub 12} concentration. After systematic optimization, the limit of detection was 1 ng mL{sup -1}. The coefficient of variation was below 0.2% for both intra- and inter-assay precision. Vitamin B{sub 12} was extracted from energy drinks with recovery ranged from 90 to 99.4%. Two different energy drinks samples were analyzed, and a good correlation was observed when the data were compared with a reference enzyme linked immuno sorbent assay (ELISA

  7. Absorption and transport of radioactive /sup 57/Co-vitamin B/sub 12/ in experimental giardiasis in rats

    Energy Technology Data Exchange (ETDEWEB)

    Deka, N.C.; Sehgal, A.K.; Chnuttani, P.N. (Post-Graduate Inst. of Medical Education and Research, Chandigarh (India))

    1981-11-01

    Giardiasis was produced in weanling albino rats by feeding suspension of Giardia lamblia cysts isolated from human stool. Experiments were carried out to assess the absorption and transport through intestinal wall of /sup 57/Co-vitamin B/sub 12/ in these rats. The results showed a significant impairment of the absorption of the vitamin in the rats with experimental giardiasis. However, the transport of the vitamin B/sub 12/ was unimpaired.

  8. Laser controlled melting of HSLA steel surface with presence of B{sub 4}C particles

    Energy Technology Data Exchange (ETDEWEB)

    Yilbas, B.S., E-mail: bsyilbas@kfupm.edu.sa [ME Department, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Patel, F., E-mail: faheemmp@kfupm.edu.sa [ME Department, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Karatas, C., E-mail: doc_cihan@hotmail.com [Engineering College, Hacettepe University (Turkey)

    2013-10-01

    Laser gas assisted melting of high strength low alloy steel surface is carried out. The alloy surface is pre-prepared to contain 5% B{sub 4}C particles in a 40 μm thick carbon film prior to laser treatment process. Metallurgical and morphological changes in the laser treated layer are examined by using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. The residual stress developed and the microhardness of the resulting surface is measured. It is found that B{sub 4}C particles remain in solid phase in the surface region due to their high melting temperature. The dense layer consisting of fine grains are formed at the surface and the feathery like structure is observed below the surface vicinity, which consists of martensite and nitride precipitations. The use of nitrogen at high pressure causes the formation of nitride compounds at the surface, which contributes to the volume shrinkage in the dense layer. Surface microhardness increases considerably because of attainment of high cooling rates, formation of nitride compounds, and presence of B{sub 4}C particles at the surface. .

  9. Effect of superconductivity on spin dynamics in (Y/sub 1-x/Re/sub x/)Rh/sub 4/B/sub 4/

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, K.; Fradin, F.Y.

    1982-01-01

    An adiabatic field-cycle method has been used to study spin dynamics of RE ions in (Y/sub 1-x/RE/sub x/)Rh/sub 4/B/sub 4/. Longitudinal dipolar fluctuations of RE moments are found to be the main source of the nuclear spin-lattice relaxation time of /sup 11/B. The variation of T/sub 1/ in the superconducting state is attributed to the reduction of the electronic spin-relaxation time, tau/sub m/, which is mainly determined by the RKKY type interaction mediated by the conduction electrons. 3 figures.

  10. Storage mechanism and OSL-readout possibility of Li{sub 2}B{sub 4}O{sub 7}:Mn (TLD-800)

    Energy Technology Data Exchange (ETDEWEB)

    Danilkin, M., E-mail: danilkin@ut.e [Faculty of Science and Technology, University of Tartu, Vanemuise 46, 51014 Tartu (Estonia); Jaek, I.; Kerikmaee, M.; Lust, A.; Maendar, H.; Pung, L.; Ratas, A.; Seeman, V. [Faculty of Science and Technology, University of Tartu, Vanemuise 46, 51014 Tartu (Estonia); Klimonsky, S.; Kuznetsov, V. [Faculty of Natural Sciences, D. Mendeleev University of Chemical Technology of Russia, Miusskaya Square 9, 125047 Moscow (Russian Federation)

    2010-03-15

    Thermoluminescence, dose dependences, and EPR of Mn-doped lithium tetraborate are studied. Mn is shown not to change a charge state during energy storage and release. Mn{sup 2+} amount decreases only at very high doses. The amount of Mn{sup 2+} depends on the sintering temperature and increases with temperature increase due to reduction of Mn from a higher oxidation state. X-irradiation creates optical absorption bands in Li{sub 2}B{sub 4}O{sub 7}:Mn. Optical stimulation in the UV band is effective for OSL-readout and destroys dosimetric TL peaks. The model of energy storage and release is discussed.

  11. Structure and photoluminescence properties of Na{sub 2}Y{sub 2}B{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+} phosphors for solid-state lighting application

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Dawei; Yang, Hui; Yang, Guanhui; Shi, Jianxin, E-mail: cessjx@mail.sysu.edu.cn; Wu, Mingmei, E-mail: ceswmm@mail.sysu.edu.cn; Su, Qiang

    2014-05-01

    Novel phosphors of Na{sub 2}Y{sub 2}B{sub 2}O{sub 7}:Ce{sup 3+} and Na{sub 2}Y{sub 2}B{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+} were synthesized by a solid-state process and characterized with X-ray diffraction, photoluminescence (PL), PL excitation (PLE), and fluorescence decay time. The relationship between the observed Ce{sup 3+} emission properties and the crystal structure of Na{sub 2}Y{sub 2}B{sub 2}O{sub 7} is built and the result shows that Ce{sup 3+} ions occupy two non-equivalent Y{sup 3+} sites in the host. The codoping of Tb{sup 3+} in Na{sub 2}Y{sub 2}B{sub 2}O{sub 7}:Ce{sup 3+} can tune the emitting colour from blue to green and increase the luminescence quantum efficiency to 75.2% by the energy transfer of Ce{sup 3+}→Tb{sup 3+}. The energy transfer processes of Ce{sup 3+}–Ce{sup 3+} and Ce{sup 3+}–Tb{sup 3+} are analysed and determined to be electric dipole–dipole and dipole–quadrupole, respectively. The broad PLE spectra of Na{sub 2}Y{sub 2}B{sub 2}O{sub 7}:Ce{sup 3+} and Na{sub 2}Y{sub 2}B{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+} are well matched with the emission from near UV LED chips, which indicates that they are promising blue and green phosphors for phosphor-converted white LEDs. - Graphical abstract: Colour-tunable phosphors Na{sub 2}Y{sub 2}B{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+} with optimal quantum yield of 75.2% are synthesized and the phosphors can be served as n-UV pumped materials for LEDs. - Highlights: • Green phosphor Na{sub 2}Y{sub 2}B{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+} with quantum efficiency of 75.2% for n-UV application is synthesized. • The site occupation of Ce{sup 3+} in Na{sub 2}Y{sub 2}B{sub 2}O{sub 7} is investigated with the crystal structure and photoluminescence spectra. • The energy transfer of Ce{sup 3+}–Ce{sup 3+} and Ce{sup 3+}–Tb{sup 3+}, which is responsible to the tunable emitting colour of the phosphor, is demonstrated and the mechanism is studied.

  12. Atomic layer deposition of boron-containing films using B{sub 2}F{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Mane, Anil U., E-mail: amane@anl.gov; Elam, Jeffrey W. [Argonne National Laboratory, Argonne, Illinois 60126 (United States); Goldberg, Alexander; Halls, Mathew D. [Schrödinger, Inc., San Diego, California 92122 (United States); Seidel, Thomas E. [Seitek50, Palm Coast, Florida 32135 (United States); Current, Michael I. [Current Scientific, San Jose, California 95124 (United States); Despres, Joseph; Byl, Oleg; Tang, Ying; Sweeney, Joseph [Entegris, Danbury, Connecticut 06810 (United States)

    2016-01-15

    Ultrathin and conformal boron-containing atomic layer deposition (ALD) films could be used as a shallow dopant source for advanced transistor structures in microelectronics manufacturing. With this application in mind, diboron tetrafluoride (B{sub 2}F{sub 4}) was explored as an ALD precursor for the deposition of boron containing films. Density functional theory simulations for nucleation on silicon (100) surfaces indicated better reactivity of B{sub 2}F{sub 4} in comparison to BF{sub 3}. Quartz crystal microbalance experiments exhibited growth using either B{sub 2}F{sub 4}-H{sub 2}O for B{sub 2}O{sub 3} ALD, or B{sub 2}F{sub 4}-disilane (Si{sub 2}H{sub 6}) for B ALD, but in both cases, the initial growth per cycle was quite low (≤0.2 Å/cycle) and decreased to near zero growth after 8–30 ALD cycles. However, alternating between B{sub 2}F{sub 4}-H{sub 2}O and trimethyl aluminum (TMA)-H{sub 2}O ALD cycles resulted in sustained growth at ∼0.65 Å/cycle, suggesting that the dense –OH surface termination produced by the TMA-H{sub 2}O combination enhances the uptake of B{sub 2}F{sub 4} precursor. The resultant boron containing films were analyzed for composition by x-ray photoelectron spectroscopy, and capacitance measurements indicated an insulating characteristic. Finally, diffused boron profiles less than 100 Å were obtained after rapid thermal anneal of the boron containing ALD film.

  13. Influence of impurities in raw materials on zirconia-toughened mullite ceramics removed by B/sub 2/O/sub 3/

    International Nuclear Information System (INIS)

    Mechanical properties and microstructure of a zirconia toughened mullite ceramics (ZTM ceramics) prepared by using an electrically fused mullite as a raw material were studied in the present work. It was found that the raw material contained more alkali-metal ions, such as a sodium ion (Na+) and a potassium ion (K+), which were proven to be the dominant factor for deteriorating the ceramic properties. The impurities in the raw material have led to the decrease of the mechanical properties. The impurities in the raw materials have led to the decrease of the mechanical properties of ZTM ceramics by changing properties (for example, viscosity) of a glassy phase in the ceramics, especially at high temperature. In this work the mechanical properties of the ceramics were improved by adding B/sub 2/O/sub 3/ additive and its toughness at room temperature increased from 4.4 MPa under the roote m to 5.9 MPa under the roote m and that at 800 deg. C from 2.9 MPa under the roote m to 4.4 MPa under the roote m. The toughness of the ceramic at room temperature was 34% increased and that ceramics and the improvement of the ceramic properties by B/sub 2/O/sub 3/ additive were studied and their mechanisms discussed. (author)

  14. Growth process of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Chengcai [Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Nai Xueying [Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008 (China); Zhu Donghai [Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Guo Fengqin [Department of Basin Education, Qinghai University, Xining 810016 (China); Zhang Yongxing [Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Li Wu, E-mail: zccgn2012@163.com [Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008 (China)

    2013-01-15

    The reactions occurred and growth process in the preparation of copper aluminum borate (Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17}) whiskers based on flux method (Al{sub 2}(SO{sub 4}){sub 3}/CuSO{sub 4}/H{sub 3}BO{sub 3} as raw materials, K{sub 2}SO{sub 4} as flux) were investigated. The thermogravimetric and differential scanning calorimetry analysis (TG-DSC), inductively coupled plasma atomic emission spectrum analysis (ICP-AES) and X-ray diffraction analysis (XRD) results of reactants mixture quenched at various temperatures and phase diagrams of K{sub 2}SO{sub 4}-Al{sub 2}(SO{sub 4}){sub 3} system and B{sub 2}O{sub 3}-Al{sub 2}O{sub 3} system showed that the reaction process proceeds through three steps: the formation and decomposition of two different kinds of potassium aluminum sulfate (K{sub 3}Al(SO{sub 4}){sub 3} and KAl(SO{sub 4}){sub 2}); the formation of aluminum borate (Al{sub 4}B{sub 2}O{sub 9}) and decomposition of copper sulfate (CuSO{sub 4}) and boric acid (H{sub 3}BO{sub 3}); growth and formation of copper aluminum borate (Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17}) whiskers. The scanning electron microscopy (SEM) analysis results indicated that morphology in growth of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers develops through three stages: nanoparticles, fan-shaped whiskers and agminate-needlelike whiskers. - Graphical abstract: The morphology in growth of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers develops through three stages: nanoparticles, fan-shaped whiskers and agminate-needlelike whiskers. Highlights: Black-Right-Pointing-Pointer Reaction process in the preparation of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers was researched systematically. Black-Right-Pointing-Pointer Crystal growth mechanism of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers was proposed by theory and experiments. Black-Right-Pointing-Pointer Properties of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} were analyzed by instruments, such as TG-DSC, ICP-AES, XRD and SEM.

  15. Crystal structure and physical properties of the new ternary compound MgNi{sub 7}B{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Liao, C.Z. [Key Laboratory of Nonferrous Metals and New Processing Technology of Materials, Ministry of Education, Guangxi University, Nanning Guangxi 530004 (China); National Laboratory for Superconductivity, Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190 (China); Dong, C., E-mail: chengdon@iphy.ac.c [National Laboratory for Superconductivity, Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190 (China); Zeng, L.M. [Key Laboratory of Nonferrous Metals and New Processing Technology of Materials, Ministry of Education, Guangxi University, Nanning Guangxi 530004 (China); He, B. [National Laboratory for Superconductivity, Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190 (China); Luzhou Medical College, Luzhou, Sichuan 646000 (China); Cao, W.H. [Key Laboratory of Nonferrous Metals and New Processing Technology of Materials, Ministry of Education, Guangxi University, Nanning Guangxi 530004 (China); National Laboratory for Superconductivity, Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190 (China); Yang, L.H. [National Laboratory for Superconductivity, Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2010-03-18

    A new compound MgNi{sub 7}B{sub 3} in the Mg-Ni-B ternary system was prepared by solid state reaction and its crystal structure was determined using X-ray powder diffraction data. The MgNi{sub 7}B{sub 3} compound crystallizes with ErNi{sub 7}B{sub 3} structure type (space group I4{sub 1}/amd, a = 7.4877(2) A, c = 15.4879(4) A, Z = 8.), and the Rietveld refinement of the crystal structure was performed which gave R{sub wp} = 7.02%, R{sub p} = 4.96%. The MgNi{sub 7}B{sub 3} sample was characterized by magnetization and electric resistivity measurements. MgNi{sub 7}B{sub 3} exhibits metallic behavior in the temperature range from 5 to 300 K and shows spin-glass-like behavior at low temperature with the spin freezing temperature (T{sub f}) around 13 K.

  16. Preparation and characterization of zinc-exchanged montmorillonite and its effectiveness as aflatoxin B{sub 1} adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Dakovic, Aleksandra, E-mail: a.dakovic@itnms.ac.rs [Institute for Technology of Nuclear and Other Mineral Raw Materials, Franche d' Epere 86, P.O. Box 390, 11000 Belgrade (Serbia); Kragovic, Milan [Institute for Technology of Nuclear and Other Mineral Raw Materials, Franche d' Epere 86, P.O. Box 390, 11000 Belgrade (Serbia); Rottinghaus, George E. [Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211 (United States); Ledoux, David R.; Butkeraitis, Paula [Department of Animal Science, University of Missouri, Columbia, MO 65211-5300 (United States); Vojislavljevic, Dubravka Z. [Department of Chemistry, University of Belgrade, P.O. Box 158, 11000 Belgrade (Serbia); Zaric, Snezana D. [Department of Chemistry, University of Belgrade, P.O. Box 158, 11000 Belgrade (Serbia); Department of Chemistry, Texas A and M University at Qatar, P.O. Box 23874 Doha (Qatar); Stamenic, Ljubisav [The Vinca Institute of Nuclear Sciences, University of Belgrade, P.O. Box 522, 11001 Belgrade (Serbia)

    2012-11-15

    A zinc-exchanged montmorillonite (Zn-MONT) was prepared from a natural montmorillonite (MONT) and the adsorption of aflatoxin B{sub 1} (AFB{sub 1}) was investigated at pH 3 and 7. Characterization of Zn-MONT was done by determination of chemical composition, the point of the zero charge (pH{sub pzc}), thermal (DTA/TGA/DTG) and X-ray powder diffraction (XRPD) analysis. Adsorption of AFB{sub 1} (C{sub 0} = 4 ppm) by Zn-MONT, at different solid/liquid ratios (10, 1 and 0.5 g L{sup -1}), at pH 3 or 7, showed that its adsorption was high (over 96%) and independent of pH, similar to MONT. No desorption of AFB{sub 1} from MONT-AFB{sub 1} and Zn-MONT-AFB{sub 1} complexes occurred at pH 6.5, suggesting strong binding of AFB{sub 1} by both adsorbents. Furthermore, AFB{sub 1} adsorption by Zn-MONT followed a non-linear (Langmuir) type of isotherm at pH 3 with a calculated maximum capacity of 60.17 mg g{sup -1}. The stability of MONT-AFB{sub 1} and Zn-MONT-AFB{sub 1} complexes was evaluated by calculating the binding energies between AFB{sub 1} and metal cations using quantum chemical methods. The evaluated interaction energies of AFB{sub 1} with hydrated Zn{sup 2+}, Mg{sup 2+}, and Ca{sup 2+} cations showed that the strongest interaction was the interaction of the Zn{sup 2+} system, -70.2 kcal mol{sup -1}, whereas energies for Mg{sup 2} and Ca{sup 2+} systems were -68.8 and -62.9 kcal mol{sup -1}, respectively. The results indicate that Zn-MONT can be suitable for potential practical application as both, an antibacterial and an aflatoxin binding agent. -- Highlights: Black-Right-Pointing-Pointer Adsorption of aflatoxin B{sub 1} (AFB{sub 1}) by zinc modified montmorillonite (Zn-MONT) was studied at pH 3 and 7. Black-Right-Pointing-Pointer Presence of zinc in the interlamellar space of MONT increased adsorption of AFB{sub 1}. Black-Right-Pointing-Pointer The binding energies between AFB{sub 1} and metal cations were calculated using quantum chemical methods. Black

  17. Elastic rotation of Escherichia coli F{sub O}F{sub 1} having ε subunit fused with cytochrome b{sub 562} or flavodoxin reductase

    Energy Technology Data Exchange (ETDEWEB)

    Oka, Hideyuki [Department of Bioscience, Nagahama Institute of Bioscience and Technology, Nagahama, Shiga 526-0829 (Japan); Hosokawa, Hiroyuki; Nakanishi-Matsui, Mayumi [Department of Biochemistry, Faculty of Pharmaceutical Sciences, Iwate Medical University, Yahaba, Iwate 028-3694 (Japan); Dunn, Stanley D. [Department of Biochemistry, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Futai, Masamitsu [Department of Biochemistry, Faculty of Pharmaceutical Sciences, Iwate Medical University, Yahaba, Iwate 028-3694 (Japan); Iwamoto-Kihara, Atsuko, E-mail: a_iwamoto@nagahama-i-bio.ac.jp [Department of Bioscience, Nagahama Institute of Bioscience and Technology, Nagahama, Shiga 526-0829 (Japan)

    2014-04-18

    Highlights: • Intra-molecular rotation of F{sub O}F{sub 1} ATP synthase was observed using a small bead probe. • Carboxyl-terminus of the ε subunit was fused to cytochrome b{sub 562} or flavodoxin reductase. • The F{sub O}F{sub 1} showed continual rotation with similar rate to the wild-type enzyme. • The intra-molecular rotation is flexible and elastic. - Abstract: Intra-molecular rotation of F{sub O}F{sub 1} ATP synthase enables cooperative synthesis and hydrolysis of ATP. In this study, using a small gold bead probe, we observed fast rotation close to the real rate that would be exhibited without probes. Using this experimental system, we tested the rotation of F{sub O}F{sub 1} with the ε subunit connected to a globular protein [cytochrome b{sub 562} (ε-Cyt) or flavodoxin reductase (ε-FlavR)], which is apparently larger than the space between the central and the peripheral stalks. The enzymes containing ε-Cyt and ε-FlavR showed continual rotations with average rates of 185 and 148 rps, respectively, similar to the wild type (172 rps). However, the enzymes with ε-Cyt or ε-FlavR showed a reduced proton transport. These results indicate that the intra-molecular rotation is elastic but proton transport requires more strict subunit/subunit interaction.

  18. Measurement of the flavour-specific CP-violating asymmetry a{sub sl}{sup s} in B{sub s}{sup 0} decays

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [Fakultät Physik, Technische Universität Dortmund, Dortmund (Germany); Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amerio, S. [Sezione INFN di Padova, Padova (Italy); Amhis, Y. [LAL, Université Paris-Sud, CNRS/IN2P3, Orsay (France); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universität Zürich, Zürich (Switzerland); Andreassen, R. [University of Cincinnati, Cincinnati, OH (United States); Andrews, J.E. [University of Maryland, College Park, MD (United States); and others

    2014-01-20

    The CP-violating asymmetry a{sub sl}{sup s} is studied using semileptonic decays of B{sub s}{sup 0} and B{sup ¯}{sub s}{sup 0} mesons produced in pp collisions at a centre-of-mass energy of 7 TeV at the LHC, exploiting a data sample corresponding to an integrated luminosity of 1.0 fb{sup −1}. The reconstructed final states are D{sub s}{sup ±}μ{sup ∓}, with the D{sub s}{sup ±} particle decaying in the ϕπ{sup ±} mode. The D{sub s}{sup ±}μ{sup ∓} yields are summed over B{sup ¯}{sub s}{sup 0} and B{sub s}{sup 0} initial states, and integrated with respect to decay time. Data-driven methods are used to measure efficiency ratios. We obtain a{sub sl}{sup s}=(−0.06±0.50±0.36)%, where the first uncertainty is statistical and the second systematic.

  19. B{sub s} → D{sub s}lν{sub l} near zero recoil in and beyond the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Atoui, Mariam; Morenas, Vincent [Universite Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, Aubiere Cedex (France); Becirevic, Damir; Sanfilippo, Francesco [Universite Paris Sud and CNRS, Centre d' Orsay, Laboratoire de Physique Theorique (Bat 210), Orsay-Cedex (France)

    2014-05-15

    We compute the normalization of the form factor entering the B{sub s} → D{sub s}lν decay amplitude by using numerical simulations of QCD on the lattice. From our study with N{sub f} = 2 dynamical light quarks, and by employing the maximally twisted Wilson quark action, we obtain in the continuum limit G(1) = 1.052(46). We also compute the scalar and tensor form factors in the region near zero recoil and find f{sub 0}(q{sub 0}{sup 2})/f{sub +}(q{sub 0}{sup 2}) = 0.77(2), f{sub 0}(q{sub 0}{sup 2},m{sub b})/f{sub +}(q{sub 0}{sup 2}) = 1.08(7), for q{sub 0}{sup 2} = 11.5 GeV{sup 2}. The latter results are useful for searching the effects of physics beyond the Standard Model in B{sub s} → D{sub s}lν decays. Our results for the similar form factors relevant to the non-strange case indicate that the method employed here can be used to achieve the precision determination of the B → Dlν decay amplitude as well. (orig.)

  20. Predictions for the anti B{sup 0} → anti K{sup *0} X(YZ) and anti B{sub s}{sup 0} → φ X(YZ) with X(4160), Y(3940), Z(3930)

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Wei-Hong [Guangxi Normal University, Department of Physics, Guilin (China); Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Molina, R.; Doering, M. [The George Washington University, Washington, DC (United States); Xie, Ju-Jun [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Institute of Modern Physics of CAS and Lanzhou University, Research Center for Hadron and CSR Physics, Lanzhou (China); Institute of Theoretical Physics, Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Beijing (China); Oset, E. [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Centro Mixto Universidad de Valencia-CSIC Institutos de Investigacion de Paterna, Departamento de Fisica Teorica y IFIC, Valencia (Spain)

    2015-05-15

    We investigate the decay of anti B{sup 0} → anti K{sup *0}R and anti B{sub s}{sup 0} → φR with R being the X(4160), Y(3940), Z(3930) resonances. Under the assumption that these states are dynamically generated from the vector-vector interaction, as has been concluded from several theoretical studies, we use a reaction mechanism of quark production at the elementary level, followed by hadronization of one final q anti q pair into two vectors and posterior final state interaction of this pair of vector mesons to produce the resonances. With this procedure we are able to predict five ratios for these decays, which are closely linked to the dynamical nature of these states, and also predict the order of magnitude of the branching ratios which we find of the order of 10{sup -4}, well within the present measurable range. In order to further test the dynamical nature of these resonances we study the anti B{sub s}{sup 0} → φ D* anti D* and anti B{sub s}{sup 0} → φ D{sub s}{sup *} anti D{sub s}{sup *} decays close to the D* anti D* and D{sub s}{sup *} anti D{sub s}{sup *} thresholds and make predictions for the ratio of the mass distributions in these decays and the anti B{sub s}{sup 0} → φR decay widths. The measurement of these decays rates can help unravel the nature of these resonances. (orig.)

  1. The leukotriene B{sub 4} receptor, BLT1, is required for the induction of experimental autoimmune encephalomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Kihara, Yasuyuki, E-mail: kihara-yasuyuki@umin.net [Department of Biochemistry and Molecular Biology, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Yokomizo, Takehiko [Department of Medical Biochemistry, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582 (Japan); Core Research for Embryonic Science and Technology (CREST), Japan Science and Technology Agency (Japan); Kunita, Akiko; Morishita, Yasuyuki; Fukayama, Masashi [Department of Pathology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033 (Japan); Ishii, Satoshi; Shimizu, Takao [Department of Biochemistry and Molecular Biology, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2010-04-09

    Leukotriene B{sub 4} (LTB{sub 4}) is a potent chemoattractant and activator of neutrophils, macrophages and T cells. These cells are a key component of inflammation and all express BLT1, a high affinity G-protein-coupled receptor for LTB{sub 4}. However, little is known about the neuroimmune functions of BLT1. In this study, we describe a distinct role for BLT1 in the pathology of experimental autoimmune encephalomyelitis (EAE) and T{sub H}1/T{sub H}17 immune responses. BLT1 mRNA was highly upregulated in the spinal cord of EAE mice, especially during the induction phase. BLT1{sup -/-} mice had delayed onset and less severe symptoms of EAE than BLT1{sup +/+} mice. Additionally, inflammatory cells were recruited to the spinal cord of asymptomatic BLT1{sup +/+}, but not BLT1{sup -/-} mice before the onset of disease. Ex vivo studies showed that both the proliferation and the production of IFN-{gamma}, TNF-{alpha}, IL-17 and IL-6 were impaired in BLT1{sup -/-} cells, as compared with BLT1{sup +/+} cells. Thus, we suggest that BLT1 exacerbates EAE by regulating the migration of inflammatory cells and T{sub H}1/T{sub H}17 immune responses. Our findings provide a novel therapeutic option for the treatment of multiple sclerosis and other T{sub H}17-mediated diseases.

  2. Measurement of the effective B{sub s}{sup 0}{yields}K{sup +}K{sup -} lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adametz, A. [Physikalisches Institut, Ruprecht-Karls-Universitaet Heidelberg, Heidelberg (Germany); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); and others

    2012-10-02

    A precise determination of the effective B{sub s}{sup 0}{yields}K{sup +}K{sup -} lifetime can be used to constrain contributions from physics beyond the Standard Model in the B{sub s}{sup 0} meson system. Conventional approaches select B meson decay products that are significantly displaced from the B meson production vertex. As a consequence, B mesons with low decay times are suppressed, introducing a bias to the decay time spectrum which must be corrected. This analysis uses a technique that explicitly avoids a lifetime bias by using a neural network based trigger and event selection. Using 1.0 fb{sup -1} of data recorded by the LHCb experiment, the effective B{sub s}{sup 0}{yields}K{sup +}K{sup -} lifetime is measured as 1.455{+-}0.046(stat.){+-}0.006(syst.)ps.

  3. Branching rules for Weyl group orbits of simple Lie algebras B{sub n}, C{sub n} and D{sub n}

    Energy Technology Data Exchange (ETDEWEB)

    Larouche, M; Patera, J, E-mail: larouche@dms.umontreal.ca, E-mail: patera@crm.umontreal.ca [Centre de Recherches Mathematiques, Universite de Montreal, C.P. 6128 Centre-ville, Montreal, H3C 3J7, Quebec (Canada)

    2011-03-18

    The orbits of Weyl groups W(B{sub n}), W(C{sub n}) and W(D{sub n}) of the simple Lie algebras B{sub n}, C{sub n} and D{sub n} are reduced to the union of the orbits of Weyl groups of the maximal reductive subalgebras of B{sub n}, C{sub n} and D{sub n}. Matrices transforming points of W(B{sub n}), W(C{sub n}) and W(D{sub n}) orbits into points of subalgebra orbits are listed for all cases n {<=} 8 and for the infinite series of algebra-subalgebra pairs: B{sub n} superset of B{sub n-1} x U{sub 1}, B{sub n} superset of D{sub n}, B{sub n} superset of B{sub n-k} x D{sub k}, B{sub n} superset of A{sub 1}, C{sub n} superset of C{sub n-k} x C{sub k}, C{sub n} superset of A{sub n-1} x U{sub 1}, C{sub n} superset of A{sub 1}, D{sub n} superset of A{sub n-1} x U{sub 1}, D{sub n} superset of D{sub n-1} x U{sub 1}, D{sub n} superset of B{sub n-1}, D{sub n} superset of B{sub n-k-1} x B{sub k}, D{sub n} superset of D{sub n-k} x D{sub k}. Numerous special cases and examples are shown.

  4. Preparation and characterization of B{sub 4}C coatings for advanced research light sources

    Energy Technology Data Exchange (ETDEWEB)

    Störmer, Michael, E-mail: michael.stoermer@hzg.de [Helmholtz-Zentrum Geesthacht, Max-Planck-Strasse 1, D-21502 Geesthacht (Germany); Siewert, Frank [Helmholtz-Zentrum Berlin, Albert-Einstein-Strasse 15, 12489 Berlin (Germany); Sinn, Harald [European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg (Germany)

    2016-01-01

    The challenging specifications for long X-ray mirrors for upcoming free-electron lasers can be achieved, especially for maintaining below 2 nm peak-to-valley shape error along the optical aperture of approximately 1 m-long mirrors. X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B{sub 4}C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30–60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B{sub 4}C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B{sub 4}C layers are discussed according to thickness uniformity, density

  5. Signatures of spin-glass behaviour in PrIr{sub 2}B{sub 2} and heavy fermion behaviour in PrIr{sub 2}B{sub 2}C

    Energy Technology Data Exchange (ETDEWEB)

    Anupam; Hossain, Z [Department of Physics, Indian Institute of Technology, Kanpur 208016 (India); Anand, V K; Adroja, D T [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX (United Kingdom); Geibel, C, E-mail: vivekkranand@gmail.com [Max Planck Institute for Chemical Physics of Solids, 01187 Dresden (Germany)

    2011-09-21

    The magnetic and transport properties of PrIr{sub 2}B{sub 2} and PrIr{sub 2}B{sub 2}C have been investigated by dc and ac magnetic susceptibility, specific heat, electrical resistivity and magnetoresistance measurements. PrIr{sub 2}B{sub 2} forms in CaRh{sub 2}B{sub 2}-type orthorhombic crystal structure (space group Fddd). At low fields the dc magnetic susceptibility of PrIr{sub 2}B{sub 2} exhibits a sharp anomaly near 46 K which is followed by an abrupt increase below 10 K with a peak at 6 K, and split-up in ZFC and FC data below 46 K. In contrast, the specific heat exhibits only a broad Schottky type hump near 9 K which indicates that there is no long range magnetic order in this compound. The thermo-remanent magnetization is found to decay very slowly with a mean relaxation time {tau} = 3917 s. An ac magnetic susceptibility measurement also observes two sharp anomalies; the peak positions strongly depend on the frequency and shift towards high temperature with an increase in frequency, obeying the Vogel-Fulcher law as expected for a canonical spin-glass system. The two spin-glass transitions occur at freezing temperatures T{sub f1} = 36 K and T{sub f2} = 3.5 K with shifts in the freezing temperatures per decade of frequency {delta}T{sub f1} = 0.044 and {delta}T{sub f2} = 0.09. An analysis of the frequency dependence of the transition temperature with critical slowing down, {tau}{sub max}/{tau}{sub 0} = [(T{sub f}-T{sub SG})/T{sub SG}]{sup -z{nu},} gives {tau}{sub 0} = 10{sup -7} s and exponent z{nu} = 8, and the Vogel-Fulcher law gives an activation energy of 84 K for T{sub f1} and 27.5 K for T{sub f2}. While z{nu} = 8 is typical for spin-glass system, the characteristic relaxation time {tau}{sub 0} = 10{sup -7} s is very large and comparable to that of superspin-glass systems. An addition of C in PrIr{sub 2}B{sub 2} leads to PrIr{sub 2}B{sub 2}C which forms in LuNi{sub 2}B{sub 2}C-type tetragonal structure (space group I4/mmm) and remains paramagnetic down to

  6. Measurement of the effective B{sub s}{sup 0}{yields}K{sup +}K{sup -} lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); Archilli, F. [Laboratori Nazionali dell' INFN di Frascati, Frascati (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Arrabito, L. [CC-IN2P3, CNRS/IN2P3, Lyon-Villeurbanne (France); and others

    2012-02-01

    A measurement of the effective B{sub s}{sup 0}{yields}K{sup +}K{sup -} lifetime is presented using approximately 37 pb{sup -1} of data collected by LHCb during 2010. This quantity can be used to put constraints on contributions from processes beyond the Standard Model in the B{sub s}{sup 0} meson system and is determined by two complementary approaches as {tau}{sub KK}=1.440{+-}0.096 (stat){+-}0.008 (syst){+-}0.003 (model) ps.

  7. Continuum limit of the leading order HQET form factor in B{sub s}→Klν decays

    Energy Technology Data Exchange (ETDEWEB)

    Bahr, Felix; Banerjee, Debasish; Koren, Mateusz; Simma, Hubert; Sommer, Rainer [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Bernardoni, Fabio [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Technische Univ. Dresden (Germany). Medizinische Fakultaet ' ' Carl Gustav Carus' ' ; Joseph, Anosh [Cambridge Univ. (United Kingdom). Dept. of Applied Mathematics and Theoretical Physics (DAMTP); Collaboration: ALPHA Collaboration

    2016-01-15

    We discuss the computation of form factors for semi-leptonic decays of B-, B{sub s}- mesons in lattice QCD. Considering in particular the example of the static B{sub s} form factors we demonstrate that after non-perturbative renormalization the continuum limit can be taken with confidence. The resulting precision is of interest for extractions of V{sub ub}. The size of the corrections of order 1/m{sub b} is just estimated at present but it is expected that their inclusion does not pose significant difficulties.

  8. B{sub s}{sup 0}–B{sup -bar}{sub s}{sup 0} mixing within minimal flavor-violating two-Higgs-doublet models

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Qin [Institute of Particle and Nuclear Physics, Henan Normal University, 453007, Xinxiang, Henan, People’s Republic of (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, People’s Republic of (China); Li, Pei-Fu [Institute of Particle and Nuclear Physics, Henan Normal University, 453007, Xinxiang, Henan, People’s Republic of (China); Li, Xin-Qiang, E-mail: xqli@itp.ac.cn [Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, 430079, Wuhan, Hubei, People’s Republic of (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, People’s Republic of (China)

    2015-12-15

    In the “Higgs basis” for a generic 2HDM, only one scalar doublet gets a nonzero vacuum expectation value and, under the criterion of minimal flavor violation, the other one is fixed to be either color-singlet or color-octet, which are named as the type-III and type-C models, respectively. In this paper, the charged-Higgs effects of these two models on B{sub s}{sup 0}–B{sup -bar}{sub s}{sup 0} mixing are studied. First of all, we perform a complete one-loop computation of the electro-weak corrections to the amplitudes of B{sub s}{sup 0}–B{sup -bar}{sub s}{sup 0} mixing. Together with the up-to-date experimental measurements, a detailed phenomenological analysis is then performed in the cases of both real and complex Yukawa couplings of charged scalars to quarks. The spaces of model parameters allowed by the current experimental data on B{sub s}{sup 0}–B{sup -bar}{sub s}{sup 0} mixing are obtained and the differences between type-III and type-C models are investigated, which is helpful to distinguish between these two models.

  9. Search for the B{sub c} meson in hadronic Z{sup 0} decays using the OPAL detector at LEP

    Energy Technology Data Exchange (ETDEWEB)

    Herndon, M.F.

    1999-01-01

    A search for decays of the B{sub c} meson was performed using data collected from 1990--1995 with the OPAL detector on or near the Z{sup 0} peak at LEP. The decay channels B{sub c}{sup +} {r_arrow} J/{psi}{pi}{sup +}, B{sub c}{sup +} {r_arrow} J/{psi}a{sub 1}{sup +} and B{sub c}{sup +} {r_arrow} J/{psi}{ell}{sup +}{nu} were investigated, where {ell} denotes an electron or a muon. Two candidates are observed in the mode B{sub c}{sup +} {r_arrow} J/{psi}{pi}{sup +}, with an estimated background of (0.63 {+-} 0.20) events. The weighted mean of the masses of the two candidates is (6.32 {+-} 0.06) GeV/c{sup 2}, which is consistent with the predicted mass of the B{sub c} meson. One candidate event is observed in the mode B{sub c}{sup +} {r_arrow} J/{psi}{ell}{sup +}{nu}, with an estimated background of (0.82 {+-} 0.19) events. No candidate events are observed in the B{sub c}{sup +} {r_arrow} J/{psi}a{sub 1}{sup +} decay mode, with an estimated background of (1.10 {+-} 0.22) events. Upper bounds at the 90% confidence level are set on the production rates for these processes.

  10. Potentialities of the LHCb experiment for the discovery of the physics beyond the standard model in the B{sub d}{sup 0} {yields} {phi}K{sub S}{sup 0} decay; Etude du potentiel de l'experience LHCb pour la decouverte de physique au-dela du modele standard dans la desintegration B{sub d}{sup 0} {yields} {phi}K{sub S}{sup 0}

    Energy Technology Data Exchange (ETDEWEB)

    Viaud, B

    2003-10-01

    The Standard Model predicts the same time-dependant CP asymmetry in both B{sub d}{sup 0} -> J/{psi}K{sub S}{sup 0} and B{sub d}{sup 0} {yields} {phi}K{sub S}{sup 0} decays. This asymmetry is proportional to sin(2*{beta}). Any difference between the CP asymmetries measured in these 2 channels would indicate the presence of new phenomena beyond the Standard Model. We study the sensitivity of the LHCb experiment to this effect. To that end, we estimate the statistical error on the measurement of sin(2*{beta}) in the B{sub d}{sup 0} {yields} {phi}K{sub S}{sup 0} channel by LHCb. We do that with the LHCb classic detector, and then with the re-optimized detector. The number of simulated background events is too small with respect to the annual statistics to obtain precise evaluations. We developed several methods to improve these evaluations. In the most optimistic case, we predict that sin(2*{beta}) would be measured in the LHCb classic configuration with a statistical error equal to 0.56. With the re-optimized detector, this error is further improved: 0.29. (author)

  11. Thermal treatment of the Fe{sub 78} Si{sub 9} B{sub 13} alloy and the analysis of it magnetic properties through Moessbauer spectroscopy and Positronium annihilation; Tratamiento termico de la aleacion Fe{sub 78} Si{sub 9} B{sub 13} y el analisis de sus propiedades magneticas mediante Espectroscopia de Moessbauer y Aniquilacion de positronio

    Energy Technology Data Exchange (ETDEWEB)

    Lopez M, A

    2005-07-01

    The present work is divided in five chapters. In the first one a general vision of the amorphous alloys is given from antecedents, structure, obtaining methods, properties and problems that at the moment, focusing us in a certain moment to the iron base alloys and the anomalous problem of hardness that it presents the alloy Fe{sub 78}Si{sub 9}B{sub 13} like previously mention us. The second chapter tries on the basic theory of the techniques of Moessbauer spectroscopy and Positron Annihilation spectroscopy, used for the characterization of our alloy as well as the complementary technique of X-ray diffraction (XRD) to observe that the amorphous phase was even studying. The third chapter describes the experimental conditions that were used to study the alloy Fe{sub 78}Si{sub 9}B{sub 13} in each one of their thermal treatments. In the fourth chapter the obtained results and their discussion are presented. In the fifth chapter the conclusions to which were arrived after analyzing the results are presented. (Author)

  12. Liquid chromatographic determination with fluorescence detection of B{sub 6} vitamers and riboflavin in milk and pharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Gatti, R. [Dipartimento di Scienze Farmaceutiche, Universita di Bologna, Via Belmeloro 6, 40126 Bologna (Italy)]. E-mail: rita.gatti2@unibo.it; Gioia, M.G. [Dipartimento di Scienze Farmaceutiche, Universita di Bologna, Via Belmeloro 6, 40126 Bologna (Italy)

    2005-05-04

    A simple, reliable and selective high performance liquid chromatographic method with fluorescence detection at different programmed wavelengths has been developed for the simultaneous analysis of B{sub 6} vitamers (pyridoxal 5'-phosphate, 4-pyridoxic acid, pyridoxal, pyridoxine and pyridoxamine) and Vitamin B{sub 2} in commercial vitaminized milk and in woman milk. The chromatographic separations were performed on a reversed phase octyl column by using a mobile phase consisting of sodium pentanesulfonate in 1% acetic acid-methanol-tetrahydrofuran under gradient elution conditions. The fluorescence intensity of pyridoxal 5'-phosphate was enhanced by post-column photochemical conversion, giving significantly different fluorescence spectra by a on-line photoreactor switched OFF and ON under irradiation at 254 nm. In addition, a simple and rapid method in isocratic conditions without the need of photochemical conversion was proposed for the analysis of Vitamin B{sub 6} and Vitamin B{sub 2} in pharmaceuticals. Linearity, precision, recovery, selectivity and sensitivity were found satisfactory for each analysed compound. Quantitation limits ranged from 26 to 240 fmol.

  13. Sintered Cr/Pt and Ni/Au ohmic contacts to B{sub 12}P{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Frye, Clint D., E-mail: frye6@llnl.gov [Lawrence Livermore National Laboratory, Livermore, California 94550 and Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506 (United States); Kucheyev, Sergei O.; Voss, Lars F.; Conway, Adam M.; Shao, Qinghui; Nikolić, Rebecca J., E-mail: nikolic1@llnl.gov [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Edgar, James H. [Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506 (United States)

    2015-05-15

    Icosahedral boron phosphide (B{sub 12}P{sub 2}) is a wide-bandgap semiconductor possessing interesting properties such as high hardness, chemical inertness, and the reported ability to self-heal from irradiation by high energy electrons. Here, the authors developed Cr/Pt and Ni/Au ohmic contacts to epitaxially grown B{sub 12}P{sub 2} for materials characterization and electronic device development. Cr/Pt contacts became ohmic after annealing at 700 °C for 30 s with a specific contact resistance of 2 × 10{sup −4} Ω cm{sup 2}, as measured by the linear transfer length method. Ni/Au contacts were ohmic prior to any annealing, and their minimum specific contact resistance was ∼l–4 × 10{sup −4} Ω cm{sup 2} after annealing over the temperature range of 500–800 °C. Rutherford backscattering spectrometry revealed a strong reaction and intermixing between Cr/Pt and B{sub 12}P{sub 2} at 700 °C and a reaction layer between Ni and B{sub 12}P{sub 2} thinner than ∼25 nm at 500 °C.

  14. Many-body effects in LuNi{sub 2}B{sub 2}C

    Energy Technology Data Exchange (ETDEWEB)

    Bergk, B; Bartkowiak, M; Ignatchik, O; Wosnitza, J [Hochfeld-Magnetlabor Dresden (HLD), Forschungszentrum Dresden-Rossendorf, D-01314 Dresden (Germany); Petzold, V; Rosner, H [Max-Planck-Institut fuer Chemische Physik fester Stoffe, D-01187 Dresden (Germany); Drechsler, S-L; Sheikin, I [Leibniz-Institute for Solid State and Materials Research (IFW-Dresden), D-01171 Dresden (Germany); Canfield, P C, E-mail: b.bergk@fzd.d [Grenoble High Magnetic Field Laboratory, CNRS, BP 166, F-38042 Grenoble Cedex 09 (France)

    2009-03-01

    We present de Haas-van Alphen measurements of the nonmagnetic borocarbide superconductor LuNi{sub 2}B{sub 2}C. The electronic band structure is extracted from the magnetic quantum oscillations in the normal state. In accordance with previous investigations we find a complex band structure with different open and closed Fermi-surface sheets. From the temperature dependence of the oscillations amplitude the effective mass of the single bands can be determined. Due to many-body interactions we observe enhancements of the effective masses compared to the results by full-potential-density-functional calculations. Therefore, we are able to determine the angular dependence of the interaction strength for the different bands separately.

  15. Sulforaphane, a cancer chemopreventive agent, induces pathways associated with membrane biosynthesis in response to tissue damage by aflatoxin B{sub 1}

    Energy Technology Data Exchange (ETDEWEB)

    Techapiesancharoenkij, Nirachara [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Fiala, Jeannette L.A. [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Navasumrit, Panida [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Croy, Robert G.; Wogan, Gerald N. [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Groopman, John D. [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 (United States); Ruchirawat, Mathuros [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Essigmann, John M., E-mail: jessig@mit.edu [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2015-01-01

    Aflatoxin B{sub 1} (AFB{sub 1}) is one of the major risk factors for liver cancer globally. A recent study showed that sulforaphane (SF), a potent inducer of phase II enzymes that occurs naturally in widely consumed vegetables, effectively induces hepatic glutathione S-transferases (GSTs) and reduces levels of hepatic AFB{sub 1}-DNA adducts in AFB{sub 1}-exposed Sprague Dawley rats. The present study characterized the effects of SF pre-treatment on global gene expression in the livers of similarly treated male rats. Combined treatment with AFB{sub 1} and SF caused reprogramming of a network of genes involved in signal transduction and transcription. Changes in gene regulation were observable 4 h after AFB{sub 1} administration in SF-pretreated animals and may reflect regeneration of cells in the wake of AFB{sub 1}-induced hepatotoxicity. At 24 h after AFB{sub 1} administration, significant induction of genes that play roles in cellular lipid metabolism and acetyl-CoA biosynthesis was detected in SF-pretreated AFB{sub 1}-dosed rats. Induction of this group of genes may indicate a metabolic shift toward glycolysis and fatty acid synthesis to generate and maintain pools of intermediate molecules required for tissue repair, cell growth and compensatory hepatic cell proliferation. Collectively, gene expression data from this study provide insights into molecular mechanisms underlying the protective effects of SF against AFB{sub 1} hepatotoxicity and hepatocarcinogenicity, in addition to the chemopreventive activity of this compound as a GST inducer. - Highlights: • This study revealed sulforaphane (SF)-deregulated gene sets in aflatoxin B{sub 1} (AFB{sub 1})-treated rat livers. • SF redirects biochemical networks toward lipid biosynthesis in AFB{sub 1}-dosed rats. • SF enhanced gene sets that would be expected to favor cell repair and regeneration.

  16. Fluorescence resonance energy transfer between perylene and riboflavin in micellar solution and analytical application on determination of vitamin B{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Bhattar, S.L.; Kolekar, G.B. [Fluorescence Spectroscopy Research Laboratory, Department of Chemistry, Shivaji University, Kolhapur 416 004, Maharashtra (India); Patil, S.R. [Fluorescence Spectroscopy Research Laboratory, Department of Chemistry, Shivaji University, Kolhapur 416 004, Maharashtra (India)], E-mail: srp_fsl@rediffmail.com

    2008-03-15

    Fluorescence resonance energy transfer (FRET) between perylene and riboflavin is studied in micellar solution of sodium dodecyl sulfate. The fluorescence of perylene is quenched by riboflavin and quenching is in accordance with Stern-Volmer relation. The efficiency of energy transfer is found to depend on the concentration of riboflavin. The value of critical energy transfer distance (R{sub 0}) calculated by using Foster relation is 32.13 A, and as it is less than 50 A, it indicates efficient energy transfer in the present system. The analytical relation was established between extent of sensitization and concentration of riboflavin, which helped to estimate vitamin B{sub 2} directly from pharmaceutical tablets.

  17. First-principles calculations of the structural, electronic and optical properties of cubic B{sub x}Ga{sub 1-x}As alloys

    Energy Technology Data Exchange (ETDEWEB)

    Guemou, M., E-mail: guemoumhamed7@gmail.com [Engineering Physics Laboratory, University Ibn Khaldoun of Tiaret, BP 78-Zaaroura, Tiaret 14000 (Algeria); Bouhafs, B. [Modelling and Simulation in Materials Science Laboratory, Physics Department, University of Sidi Bel-Abbes, 22000 Sidi Bel-Abbes (Algeria); Abdiche, A. [Applied Materials Laboratory, Research Center, University of Sidi Bel Abbes, 22000 Sidi Bel Abbes (Algeria); Khenata, R. [Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M), Departement de Technologie, Universite de Mascara, 29000 Mascara (Algeria); Al Douri, Y. [Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Perlis (Malaysia); Bin Omran, S. [Department of Physics and Astronomy, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia)

    2012-04-15

    Density functional calculations are performed to study the structural, electronic and optical properties of technologically important B{sub x}Ga{sub 1-x}As ternary alloys. The calculations are based on the total-energy calculations within the full-potential augmented plane-wave (FP-LAPW) method. For exchange-correlation potential, local density approximation (LDA) and the generalized gradient approximation (GGA) have been used. The structural properties, including lattice constants, bulk modulus and their pressure derivatives, are in very good agreement with the available experimental and theoretical data. The electronic band structure, density of states for the binary compounds and their ternary alloys are given. The dielectric function and the refractive index are also calculated using different models. The obtained results compare very well with previous calculations and experimental measurements.

  18. Analysis of the strong decay X(5568) → B{sub s}{sup 0}π{sup +} with QCD sum rules

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhi-Gang [North China Electric Power University, Department of Physics, Baoding (China)

    2016-05-15

    In this article, we take the X(5568) to be the scalar diquark-antidiquark type tetraquark state, study the hadronic coupling constant g{sub XB{sub sπ}} with the three-point QCD sum rules by carrying out the operator product expansion up to the vacuum condensates of dimension-6 and including both the connected and the disconnected Feynman diagrams; then we calculate the partial decay width of the strong decay X(5568) → B{sub s}{sup 0}π{sup +} and obtain the value Γ{sub X} = (20.5 ± 8.1) MeV, which is consistent with the experimental data Γ{sub X} = (21.9 ± 6.4{sup +5.0}{sub -2.5}) MeV from the D0 collaboration. (orig.)

  19. Pressure effects in PrT{sub 2}B{sub 2}C (T = Co, Ni, Pt): Applied and chemical pressure

    Energy Technology Data Exchange (ETDEWEB)

    Falconi, R. [Division Academica de Ciencias Basicas, Universidad Juarez Autonoma de Tabasco, Cunduacan, Tabasco 86690, A. Postal 24 (Mexico); Duran, A. [Centro de Nanociencias y Nanotecnologia, Universidad Nacional Autonoma de Mexico, A. Postal 2681, Ensenada, Baja California 22800 (Mexico); Nunez-Regueiro, M. [Institut Neel, Centre Nationale de la Recherche Scientifique, Universite Joseph Fourier, BP 166, 38042 Grenoble (France); Escudero, R. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, A. Postal 70-360, Mexico D.F. 04510 (Mexico)

    2011-09-15

    High pressure electrical resistivity {rho}{sub ab} measurements on intermetallic Pr(Co, Ni, Pt){sub 2}B{sub 2}C compounds were performed down to 2 K. At ambient pressure the {rho}{sub ab} (T) curves for the non-superconducting Pr(Co, Ni){sub 2}B{sub 2}C compounds exhibit magnetic correlations at about 10 and 4 K, respectively. At low temperatures, PrCo{sub 2}B{sub 2}C shows a large spin-dependent electron scattering in comparison to PrNi{sub 2}B{sub 2}C. Under applied pressure, the magnetic scattering tends to be suppressed more effectively in PrCo{sub 2}B{sub 2}C than in PrNi{sub 2}B{sub 2}C. The low-temperature behavior of {rho}{sub ab}(T,P) for PrNi{sub 2}B{sub 2}C and PrCo{sub 2}B{sub 2}C suggests a spin fluctuation mechanism. On the other hand, the PrPt{sub 2}B{sub 2}C compound shows superconductivity at about 6 K and under pressure its superconducting transition temperature tends to be degraded at a rate dT{sub c}/dP = - 0.34 K/GPa, as expected in compounds with transition metals. The experimental results in Co-, Ni-, and Pt-based compounds are analyzed from the point of view of the external and chemical internal pressure effects. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. New low loss A{sub 9}B{sub 9}O{sub 31} (A = La; B = Ti, Mg, Sc, Fe, Al, Ga) ceramics for microwave applications

    Energy Technology Data Exchange (ETDEWEB)

    Muhammad, Raz [Materials Research Laboratory, Department of Physics, University of Peshawar, 25120 (Pakistan); Iqbal, Yaseen, E-mail: dryaseeniqbal@yahoo.co.uk [Materials Research Laboratory, Department of Physics, University of Peshawar, 25120 (Pakistan); Reaney, Ian M. [Department of Materials Science and Engineering, University of Sheffield, S1 3JD (United Kingdom)

    2015-10-15

    A{sub n}B{sub n}O{sub 3n+2} (n = 4.5) type layered perovskite ceramics with general formula A{sub 9}B{sub 9}O{sub 31} (A = La; B = Ti, Mg, Sc, Fe, Al, Ga) were prepared via a mixed oxide solid state sintering route. X-ray diffraction analysis revealed single phase La{sub 9}(TiB){sub 9}O{sub 31} (B = Ti, Mg, Sc, Fe, Al, Ga) solid solutions with orthorhombic (Pnma) symmetry when sintered at 1500–1650 °C for 4–12 h. The temperature coefficient of resonance frequency (τ{sub f}) was influenced by the polarizability of B-site cations while relative permittivity (ε{sub r}) and quality factor (Q × f{sub o}) were dependent on the relative density. The samples investigated in the present study exhibited reasonable ε{sub r} (39–48.3), high Q × f{sub o} (11823–19070 GHz) and near zero τ{sub f} (−1.28 to −22.16 ppm/°C). These ceramics might be potential candidates for microwave devices. - Highlights: • New A{sub 9}B{sub 9}O{sub 31} (A = La; B = Ti, Mg, Sc, Fe, Al, Ga) type compounds were processed. • All the compositions formed single phase ceramics with orthorhombic (Pnma) symmetry. • The dielectric properties were strongly influenced by the processing condition. • The best dielectric properties achieved were ε{sub r} = 42, Q{sub f} = 17216 GHz and τ{sub f} ∼ −1.3 ppm/°C. • Sc- and Fe-based compounds meet the bench mark for MW applications.

  1. Ion irradiation induced structural modifications of Fe{sub 81}Mo{sub 8}Cu{sub 1}B{sub 10} NANOPERM-type alloy

    Energy Technology Data Exchange (ETDEWEB)

    Miglierini, Marcel [Institute of Nuclear and Physical Engineering, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Bratislava (Slovakia); Department of Nuclear Reactors, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, Prague (Czech Republic); Hasiak, Mariusz [Department of Mechanics and Materials Science, Wroclaw University of Technology (Poland)

    2016-05-15

    Structural modifications and their impact upon magnetic properties are studied in amorphous NANOPERM-type {sup 57}Fe{sub 81}Mo{sub 10}Cu{sub 1}B{sub 10} metallic glass exposed to irradiation with 130 keV N{sup +} ions to the total fluencies of up to 2.5 x 10{sup 17} ions/cm{sup 2}. Using surface sensitive technique of Moessbauer spectrometry, traces of crystalline phases are found already in the as-quenched state after the sample production. On the air side of the ribbons, bcc-Fe dominates whereas on the opposite wheel side, also a presence of Fe{sub 3}O{sub 4} is unveiled. The amount of surface crystallization is higher on the wheel side of the ribbons. After ion irradiation, mostly the air side is affected because it was facing the incident ions. Gradual formation of iron nitrides is observed with increasing ion fluence. Though the radiation damage exhibits itself only at this side of the ribbons, its influence upon bulk magnetic properties is clearly identified by the help of magnetic measurements. Hysteresis loops exhibit changes in their shape as well as coercive field. Along with the formation of magnetic crystalline phases (bcc-Fe and nitrides), they are caused by structural rearrangement which takes place also inside the amorphous residual phase. Structural modifications are confirmed via evolution of hyperfine magnetic fields with ion fluence. Structural modification of the {sup 57}Fe{sub 81}Mo{sub 10}Cu{sub 1}B{sub 10} alloy caused by ion irradiation as demonstrated by microstructural (Moessbauer spectrometry (a,b)) and macroscopic (hysteresis loops (c,d)) measurements. As-quenched (a,c) and 2.5 x 10{sup 17} N{sup +}/cm{sup 2} irradiated (b,d) alloys are compared. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. The transport properties of the molecular-scale B{sub 2}C and BC{sub 3} electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Li Guiqin, E-mail: ligqin@mail.tsinghua.edu.cn [Department of Physics, Tsinghua University, Beijing 100084 (China); Li Runqin [Inner Mongolia Radio and TV University, 010010 (China)

    2012-09-01

    The transport properties of the molecular-scale B{sub 2}C and BC{sub 3} electronic devices are investigated with an ab initio method combined with a nonequilibrium Green function technique. The effects of different BC graphenes and ribbon lengths on the transport properties of the devices are significant. The results show that the devices with different BC graphenes and sizes have unusual transmission coefficients, which leads to special current transport mechanisms for the devices. Notably, the current strength of the device with the shortest ribbon length is the largest in three B{sub 2}C devices, but the current strength of the device with the shortest ribbon length is the smallest for BC{sub 3} device.

  3. Observation of the decay B{sub s}{sup 0}→D{sup ¯0}ϕ

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [Fakultät Physik, Technische Universität Dortmund, Dortmund (Germany); Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amerio, S. [Sezione INFN di Padova, Padova (Italy); Amhis, Y. [LAL, Université Paris-Sud, CNRS/IN2P3, Orsay (France); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universität Zürich, Zürich (Switzerland); Andreassen, R. [University of Cincinnati, Cincinnati, OH (United States); Andrews, J.E. [University of Maryland, College Park, MD (United States); and others

    2013-12-18

    First observation of the decay B{sub s}{sup 0}→D{sup ¯0}ϕ is reported using pp collision data, corresponding to an integrated luminosity of 1.0 fb{sup −1}, collected by the LHCb experiment at a centre-of-mass energy of 7 TeV. The significance of the signal is 6.5 standard deviations. The branching fraction is measured relative to that of the decay B{sub s}{sup 0}→D{sup ¯0}K{sup ¯⁎0} to be (B(B{sub s}{sup 0}→D{sup ¯0}ϕ))/(B(B{sub s}{sup 0}→D{sup ¯0}K{sup ¯⁎0})) =0.069±0.013 (stat)±0.007 (syst). The first measurement of the ratio of branching fractions for the decays B{sub s}{sup 0}→D{sup ¯0}K{sup ¯⁎0} and B{sup 0}→D{sup ¯0}K{sup ⁎0} is found to be (B(B{sub s}{sup 0}→D{sup ¯0}K{sup ¯⁎0}))/(B(B{sup 0}→D{sup ¯0}K{sup ⁎0})) =7.8±0.7 (stat)±0.3 (syst)±0.6 (f{sub s}/f{sub d}), where the last uncertainty is due to the ratio of the B{sub s}{sup 0} and B{sup 0} fragmentation fractions.

  4. Biochemical and molecular aspects of mammalian susceptibility to aflatoxin B{sub 1} carcinogenicity

    Energy Technology Data Exchange (ETDEWEB)

    Massey, T.E.; Stewart, R.K. [Queen`s Univ., Kingston, Ontario (Canada); Daniels, J.M. [Environmental Health Centre, Ottawa, Ontario (Canada)] [and others

    1995-03-01

    Aflatoxin B{sub 1} (AFB{sub 1}) is a fungal toxin that has been implicated as a causative agent in human hepatic and extrahepatic carcinogenesis. In this review, the mechanisms involved in AFB{sub 1} toxicity are delineated, in order to describe the features that make a specific cell, tissue, or species susceptible to the mycotoxin. Important considerations include: (i) different mechanisms for bioactivation of AFB{sub 1} to its ultimate carcinogenic epoxide metabolite; (ii) the balance between bioactivation to and detoxification of the epoxide; (iii) the interaction of AFB{sub 1} epoxide with DNA and the mutational events leading to neoplastic transformation; (iv) the role of cytotoxicity in AFB{sub 1} carcinogenesis; (v) the significance of nonepoxide metabolites in toxicity; and (vi) the contribution of mycotoxin-unrelated disease processes. Although considerable controversy remains about the importance of specific events, a great deal has been learned about biochemical and molecular actions of AFB{sub 1}. 157 refs., 4 figs., 1 tab.

  5. Determination of the band structure of LuNi{sub 2}B{sub 2}C

    Energy Technology Data Exchange (ETDEWEB)

    Bergk, B. [Hochfeld-Magnetlabor, Forschungszentrum Rossendorf, Dresden (Germany); Inst. fuer Festkoerperphysik, Technische Univ. Dresden (Germany); Bartkowiak, M.; Ignatchik, O. [Hochfeld-Magnetlabor, Forschungszentrum Rossendorf, Dresden (Germany); Jaeckel, M. [Inst. fuer Festkoerperphysik, Technische Univ. Dresden (Germany); Wosnitza, J.; Rosner, H.; Petzold, V. [MPI fuer chemische Physik fester Stoffe, Dresden (Germany); Canfield, P. [Iowa State Univ. of Science and Technology, Ames (United States). Ames Lab., Condensed Matter Physics

    2007-07-01

    We present de Haas-van Alphen (dHvA) investigations on the nonmagnetic borocarbide superconductor LuNi{sub 2}B{sub 2}C which have been performed by use of the torque method in high magnetic fields up to 32 T and at low temperatures down to 50 mK. The complex band structure is extracted from the quantum oscillations in the normal state. In comparison with full-potential-local-orbital calculations of the band structure we are able to assign the observed dHvA frequencies to the different bands. Temperature dependent dHvA investigations allowed the extraction of the effective band masses for the several Fermi-surface sheets. We observe an enhancement of the effective masses compared to the theoretical calculations which is due to electron-phonon interaction. Finally, we are able to examine the angular dependence of the electron-phonon coupling for the different Fermi-surface sheets. (orig.)

  6. Measurement of the lifetime of the CP pair component of B{sub s}{sup 0} in LHCb. Validation of the phototubes of the pre-shower; Mesure du temps de vie de la composante CP paire du B{sub s}{sup 0} dans LHCb. Qualification des phototubes du preshower

    Energy Technology Data Exchange (ETDEWEB)

    Borras, D

    2006-10-15

    This manuscript discusses a twofold research: an instrumental work and a prospective physics study both conducted in the framework of the LHCb experiment (CERN), foreseen to start at the Spring 2008. The LHC machine is a proton-proton collider clocked at 40 MHz and delivering a center-of-mass energy of 14 TeV. At nominal luminosity, about 10{sup 12} pairs of b-particles will be produced in LHCb. After the remarkable achievements of the B factories (BaBar and Belle), it is established that the Standard Model (through the CKM mechanism) is the dominant source of CP violation in the B system. Moreover, no significant deviation to the Standard Model predictions is observed in the whole Flavour Physics data up to now. In this scope, the large statistics which will be available at LHCb should allow to reach rare decays potentially sensitive to New Physics contribution. it will also allow to perform precision measurements and deeply test the global consistency of the CKM predictions, in particular with the B{sub s}{sup 0} particles. This document describes a prospective study about the measurement of the lifetime of the short component of the B{sub s}{sup 0} meson, reconstructed in the final state B{sub s}{sup 0} {yields} D{sub s}{sup +}D{sub s}{sup -}, where the D{sub s} meson decays in KK{pi}. It has been shown that LHCb should reach a 2% precision on this observable for a nominal year of data taking, yielding interesting constraints on {delta}{gamma}{sub s}/{gamma}{sub s}. On the instrumentation side, the team I belong to has the charge of the entire readout of the Pre-Shower (PS) detector of the LHCb spectrometer (design, construction and qualification). My contribution was devoted to the operation of a dedicated test bench aimed at qualifying the phototubes reading the PS detector. The photodetectors which have been retained are the 64-anodes PMTs produced by the Hamamatsu company. The main physics specifications for these devices were concerning the uniformity of

  7. Determination of vitamin B/sub 6/ bioavailability in animal tissues using intrinsic and extrinsic labeling in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Ink, S.L.; Gregory, J.F. III; Sartain, D.B.

    The effect of thermal processing on the bioavailability of vitamin B/sub 6/ in liver and muscle was examined by radioisotopic enrichment of these tissues. Rats were fed a single gelled test meal containing rat liver or muscle intrinsically enriched by vascular perfusion with (/sup 3/H)vitamin B/sub 6/ or a gelled test meal containing (/sup 3/H)pyridoxine (PN). Diets were extrinsically enriched with (/sup 14/C)PN to permit a direct comparison of enrichment methods. Absorption and metabolism were examined by analysis of tissues and excreta 24 h after the test meal had been consumed. The bioavailability of (/sup 3/H)B/sub 6/ vitamers in the raw tissues was equivalent to that of (/sup 3/H)PN in controls. Thermal processing of the tissues (121/sup 0/C, 45 min) induced destruction of 25-30% of the (/sup 3/H)B/sub 6/ vitamers and weakly reduced (less than or equal to10%) the utilization of the remaining(/sup 3/H)B/sub 6/ vitamers. The presence of monosodium glutamate (MSG) during thermal processing did not alter the results. The utilization of (/sup 14/C)PN was unaffected by diet composition. These data demonstrate the high bioavailability of vitamin B/sub 6/ in animal-derived foods and support the use of isotopic enrichment methods as an alternative to conventional bioassay procedures.

  8. Cutting tool performance enhancement by using a B{sub 4}C/BCN/C-BN multilayer system

    Energy Technology Data Exchange (ETDEWEB)

    Bejarano Gaitan, G. [Technological Development Center ASTIN-SENA, Cali (Colombia); Group of Corrosion and Protection, University of Antioquia, Medellin (Colombia); Caicedo, J.C. [Technological Development Center ASTIN-SENA, Cali (Colombia); Excellence Center for Novel Materials, Universidad del Valle, Cali (Colombia); Prieto, P. [Excellence Center for Novel Materials, Universidad del Valle, Cali (Colombia); Balogh, Adam G. [Institute of Materials Science, Darmstadt University of Technology (Germany)

    2007-07-01

    Thin films of B{sub 4}C/BCN/c-BN multilayers were deposited on to AISI M2 high speed steel substrates by rf. (13.56 MHz) multi-target magnetron sputtering from high purity (99.99%) h-BN and a (99.5%)B{sub 4}C target, in Ar(90%)/N{sub 2}(10%) gasmixture. For their deposition we varied the bias voltage of the B{sub 4}C films between -50 and -250 V and, for the BCN coatings the nitrogen gas flow from 3% to 12%. A 300-nm thick TiN buffer layer was first deposited to improve the adhesion of all samples. Mechanical properties like hardness, elastic Young modulus, and adhesion were determined by nanoindentation and scratch measurements. Finally, cutting tools were carried out. Tool performance was registered as functions of bilayer numbers showed enhancement between 60% and 107% and a surface roughness reduction of 60% for cutting tools coated with 16 bilayers, compared to uncoated tools. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. The influence of Ga additions on electric and magnetic properties of Co{sub 47}Fe{sub 21}B{sub 21}Si{sub 5}Nb{sub 6} alloy in crystal and liquid states

    Energy Technology Data Exchange (ETDEWEB)

    Sidorov, V., E-mail: vesidor@mail.ru; Rojkov, I.; Mikhailov, V. [Ural State Pedagogical University, Yekaterinburg (Russian Federation); Svec, P.; Janickovic, D. [Institute of Physics SAS, Bratislava (Slovakia)

    2015-08-17

    The influence of small additions of gallium on electric resistivity and magnetic susceptibility of the bulk glass forming Co{sub 47}Fe{sub 20.9}B{sub 21.2}Si{sub 4.6}Nb{sub 6.3} alloy was studied in a wide temperature range up to 1830 K. Gallium atoms were found to increase resistivity but decrease susceptibility of the alloy. The suppositions about clusters surrounding Ga atoms in the melt and new GFA criterion are given.

  10. Effect of B{sub 2}O{sub 3} addition on the sintering behavior, dielectric and ferroelectric properties of Ba{sub 0.7}Sr{sub 0.3}TiO{sub 3} ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Rhim, S.M.; Hong, S.M.; Bak, H.J.; Kim, O.K. [Hanyang University, Ansan (Korea)

    1999-07-01

    The effect of B{sub 2}O{sub 3} addition on the sintering behavior, dielectric and ferroelectric properties of Ba{sub 0.7}Sr{sub 0.3}TiO{sub 3} ceramics were investigated. The sample with 0.5 wt% B{sub 2}O{sub 3} was sintered under 1150{sup o} C. The dielectric and ferroelectric properties of BST with 0.5 wt% B{sub 2}O{sub 3} was as good as BST without B{sub 2}O{sub 3} sintered at 1350{sup o} C and its dielectric loss was even better. When B{sub 2}O{sub 3} was added over 1.0 wt%, the overdoped B{sub 2}O{sub 3} remained in the specimens and formed a second phase, which degraded the sintering behavior, dielectric and ferroelectric properties of BST. 14 refs., 11 figs.

  11. Measurement of the B{sub c}{sup +} meson lifetime using B{sub c}{sup +} → J/ψ μ{sup +}ν{sub μ}X decays

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [University of Bristol, H.H. Wills Physics Laboratory, Bristol (United Kingdom); Collaboration: The LHCb Collaboration; and others

    2014-05-15

    The lifetime of the B{sub c}{sup +} meson is measured using semileptonic decays having a J/ψ meson and a muon in the final state. The data, corresponding to an integrated luminosity of 2 fb{sup -1}, are collected by the LHCb detector in pp collisions at a centre-of-mass energy of 8 TeV. The measured lifetime is τ = 509 ± 8 ± 12 fs, where the first uncertainty is statistical and the second is systematic. (orig.)

  12. Hybridizing boron carbide (B{sub 4}C) particles with aluminum (Al) to enhance the mechanical response of magnesium based nano-composites

    Energy Technology Data Exchange (ETDEWEB)

    Habibi, Meisam K. [Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576 (Singapore); Mechanical and Industrial Engineering Department, Qatar University, P.O. Box No. 2713, Doha (Qatar); Hamouda, Abdelmagid S. [Mechanical and Industrial Engineering Department, Qatar University, P.O. Box No. 2713, Doha (Qatar); Gupta, Manoj, E-mail: mpegm@nus.edu.sg [Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576 (Singapore)

    2013-02-15

    Highlights: Black-Right-Pointing-Pointer Presence of B{sub 4}C particles did not change the texture. Black-Right-Pointing-Pointer Hybridizing agent improves the grain refinement efficiency. Black-Right-Pointing-Pointer Presence of Al-B{sub 4}C particle intensified the prismatic texture compared to Mg. Black-Right-Pointing-Pointer Hybridizing agent improves, further, the mechanical response of Mg/B{sub 4}C system. - Abstract: In this work, we synthesized and investigated the mechanical performance of magnesium (Mg) nano-composites containing either B{sub 4}C or hybrid Al-B{sub 4}C particles (B{sub 4}C particles hybridized with Al using ball milling) synthesized through powder metallurgy route using microwave assisted rapid sintering technique followed by hot extrusion. Compared to monolithic Mg, microstructural characterizations revealed presence of porosity along the particles boundaries and reduction in average matrix grain size. Among the different nano-composite formulations, the Mg/0.66B{sub 4}C nano-composite exhibited the best improvement, though marginal, in tensile yield strength (0.2% YS), compressive yield strength (0.2% CYS), ultimate tensile strength (UTS), ultimate compressive strength (UCS) and tensile failure strain (FS{sup t}) (up to +10%, +7.5%, +2%, +36%, and 12%, respectively) compared to pure Mg while compressive failure strain (FS{sup c}) was compromised. To improve the mechanical response of Mg/B{sub 4}C nano-composites further, the best observed B{sub 4}C content was hybridized with Al to outcome hybrid Al-B{sub 4}C particles. The effect of presence of hybridized B{sub 4}C particles with Al (Al-B{sub 4}C) in the case of hierarchical Mg/0.92Al-0.66B{sub 4}C configuration exhibits an improvement of +8.3% (0.2% YS), +29% (0.2% CYS), +45% (UTS) and +6.2 (UCS) compared to its Mg/0.66B{sub 4}C nano-composite counterpart whereas both FS{sup t} and FS{sup c} were compromised. Considering the crystallographic texture, the effect of presence of B{sub 4

  13. Optical conductivity of LuNi{sub 2}B{sub 2}C in the terahertz range

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, T.; Pronin, A.V.; Wosnitza, J. [Hochfeld-Magnetlabor Dresden (HLD), FZ Dresden-Rossendorf, 01314 Dresden (Germany); Niemeier, T.; Holzapfel, B. [Leibniz-Institut fuer Festkoerper- und Werkstoffforschung, 01171 Dresden (Germany)

    2010-07-01

    Using a backward-wave-oscillator-based setup in a Mach-Zehnder interferometer arrangement, we have measured the temperature- and frequency-dependent transmission and phase-shift spectra of LuNi{sub 2}B{sub 2}C films on MgO substrates in the range 200 GHz-1.4 THz. From the measured spectra, we have directly calculated the complex optical conductivity. We observe a clear signature of the superconducting energy gap in the spectra. In the talk, a comparison of the experimentally obtained spectra with theoretical predictions for a multi-band superconductor is given.

  14. Effect of magnetism on superconductivity in rare-earth compounds RE Ni{sub 2} B{sub 2} C

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Z.; Guenzburger, Diana; Baggio-Saitovitch, E.M. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Ellis, D.E. [Northwestern Univ., Evanston, IL (United States). Materials Research Center

    1995-12-01

    Spin-polarized first-principles density-functional electronic structure calculations were performed for 73-atoms embedded-clusters representing antiferromagnetic RE Ni{sub 2} B{sub 2} C (RE=Pr, Nd, Sm, Gd, Ho, Tm). A substantial difference in the extend of the exchange polarization of the conduction electrons between early and late rare-earth compounds is revealed. This result is believed to be relevant to phenomena of coexistence of superconductivity and magnetism in these compounds. (author). 24 refs., 4 figs., 1 tab.

  15. Temperature dependence of the coercive field of gas atomized Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3}Cu{sub 1}

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Escorial, A., E-mail: age@cenim.csic.es [CENIM-CSIC, Avda, Gregorio del Amo, 8, 28040 Madrid (Spain); Lieblich, M. [CENIM-CSIC, Avda, Gregorio del Amo, 8, 28040 Madrid (Spain); Hernando, A.; Aragon, A.; Marin, P. [Instituto de Magnetismo Aplicado, IMA, P.O. Box 155, 28230 Madrid (Spain)

    2012-09-25

    Highlights: Black-Right-Pointing-Pointer An anomalous thermal dependence of the coercive field of gas atomized Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3}Cu{sub 1} powder particles under 25 {mu}m powder particle, increasing Hc as temperature increases. Black-Right-Pointing-Pointer It is proposed that Cu rich regions at inter-grain boundaries could act as exchange decoupling regions contributing to the thermal increase of coercivity. Black-Right-Pointing-Pointer This anomalous thermal dependence points out that tailoring microstructure and size, by controlling the cooling rate of more adequate multiphase systems, could be a promising procedure to develop soft or hard magnets, avoiding Rare Earths metals that is nowadays an important target for the engineering of magnetic materials. - Abstract: In this work, the dependence of the coercive field of Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3}Cu{sub 1} gas atomized powder with the temperature for different particle sizes has been studied, observing an anomalous behavior in the under 25 powder particle size fraction. This unusual behavior is related with the microstructure of the powder, and is attributed to the presence of a multiphase magnetic system, with non-magnetic regions decoupling the ferromagnetic domains.

  16. Anomalous suppression of transport critical current below B/sub c/2 (T) in oriented sintered samples of DyBa2Cu3O7

    International Nuclear Information System (INIS)

    Measurements of the transport critical current density (J/sub c//sub t/ ) of textured sintered samples of DyBa2 Cu3 O7 have been made as a function of temperature in magnetic fields up to 27 T. Data with the current orthogonal to the applied field for the high B/sub c/2 (T) (Bperpendicularc axis) and the low B/sub c/2 (T) (Bparallelc axis) orientations are presented. We report the anomalous suppression of the transport critical current when current flows along the c axis at 24 T and 4.2 K, a field which is well below B/sub c/2 (∼100 T)= at this temperature

  17. Effect of sintering parameters on mechanical properties and microstructures of B{sub 4}C/TiB{sub 2} ceramic composites

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Junlong; Liu, Changxia; Wang, Liangshen; Feng, Baofu; Xie, Zaiyu [Ludong Univ., Yantai (China). School of Transportation; Li, Bin [Luoyang Institute of Science and Technology (China). Dept. of Mechanical Engineering

    2016-01-15

    B{sub 4}C/TiB{sub 2} ceramic composites were fabricated using in-situ reaction and hot-pressing. The effects of sintering parameters on mechanical properties and microstructures of B{sub 4}C/TiB{sub 2} ceramic composites are analyzed and discussed. Composites sintered at 1950 C for 60 min exhibited good mechanical properties. The relationship between bending strength and sintering parameters was similar to that between indentation fracture resistance and sintering parameters. The relationship between Vickers hardness and sintering parameters was consistent with that between relative density and sintering parameters. Analysis of microstructures indicated that the mechanical properties of B{sub 4}C/TiB{sub 2} ceramic composites were affected by the porosity, interface bonding among grains, development of grains and fracture mechanism of the composites.

  18. First observation of B{sub s}{sup 0}{yields}J/{psi}f{sub 0}(980) decays

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alessio, F. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Amoraal, J. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); Arrabito, L. [CC-IN2P3, CNRS/IN2P3, Lyon-Villeurbanne (France); Artuso, M. [Syracuse University, Syracuse, NY (United States); Aslanides, E. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France)

    2011-04-04

    Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the hadronic decay B{sub s}{sup 0}{yields}J/{psi}f{sub 0}(980) is observed. This CP eigenstate mode could be used to measure mixing-induced CP violation in the B{sub s}{sup 0} system. Using a fit to the {pi}{sup +}{pi}{sup -} mass spectrum with interfering resonances gives R{sub f0/{phi}}{identical_to}({Gamma}(B{sub s}{sup 0}{yields}J/{psi}f{sub 0},f{sub 0}{yields}{pi}{sup +}{pi}{sup -}))/({Gamma}(B{sub s}{sup 0}{yields}J/{psi}{phi},{phi}{yields}K{sup +}K{sup -})) =0.252{sub -0.032-0.033}{sup +0.046+0.027}. In the interval {+-}90 MeV around 980 MeV, corresponding to approximately two full f{sub 0} widths we also find R'{identical_to}({Gamma}(B{sub s}{sup 0}{yields}J/{psi}{pi}{sup +}{pi}{sup -},|m({pi}{sup +}{pi}{sup -})-980 MeV|<90 MeV))/({Gamma}(B{sub s}{sup 0}{yields}J/{psi}{phi},{phi}{yields}K{sup +}K{sup -})) =0.162{+-}0.022{+-}0.016, where in both cases the uncertainties are statistical and systematic, respectively.

  19. (Pt{sub 1–x}Cu{sub x}){sub 3}Cu{sub 2}B and Pt{sub 9}Cu{sub 3}B{sub 5}, the first examples of copper platinum borides. Observation of superconductivity in a novel boron filled β-Mn-type compound

    Energy Technology Data Exchange (ETDEWEB)

    Salamakha, Leonid P. [Institute of Solid State Physics, TU Wien, A-1040 Wien (Austria); Sologub, Oksana, E-mail: oksana.sologub@univie.ac.at [Institute of Solid State Physics, TU Wien, A-1040 Wien (Austria); Stöger, Berthold [Institute of Chemical Technologies and Analytics, TU Wien, A-1040 Wien (Austria); Michor, Herwig; Bauer, Ernst [Institute of Solid State Physics, TU Wien, A-1040 Wien (Austria); Rogl, Peter F. [Institute of Physical Chemistry, University of Vienna, A-1090 Wien (Austria)

    2015-09-15

    New ternary copper platinum borides have been synthesized by arc melting of pure elements followed by annealing at 600 °C. The structures have been studied by X-ray single crystal and powder diffraction. (Pt{sub 1−x}Cu{sub x}){sub 3}Cu{sub 2}B (x=0.33) forms a B-filled β-Mn-type structure (space group P4{sub 1}32; a=0.6671(1) nm). Cu atoms are distributed preferentially on the 8c atom sites, whereas the 12d site is randomly occupied by Pt and Cu atoms (0.670(4) Pt±0.330(4) Cu). Boron is located in octahedral voids of the parent β-Mn-type structure. Pt{sub 9}Cu{sub 3}B{sub 5} (space group P-62m; a=0.9048(3) nm, c=0.2908(1) nm) adopts the Pt{sub 9}Zn{sub 3}B{sub 5–δ}-type structure. It has a columnar architecture along the short translation vector exhibiting three kinds of [Pt{sub 6}] trigonal prism columns (boron filled, boron semi-filled and empty) and Pt channels with a pentagonal cross section filled with Cu atoms. The striking structural feature is a [Pt{sub 6}] cluster in form of an empty trigonal prism at the origin of the unit cell, which is surrounded by coupled [BPt{sub 6}] and [Pt{sub 6}] trigonal prisms, rotated perpendicularly to the central one. There is no B–B contact as well as Cu–B contact in the structure. The relationships of Pt{sub 9}Cu{sub 3}B{sub 5} structure with the structure of Ti{sub 1+x}Os{sub 2−x}RuB{sub 2} as well as with the structure families of metal sulfides and aluminides have been elucidated. (Pt{sub 1–x}Cu{sub x}){sub 3}Cu{sub 2}B (x=0.3) (B-filled β-Mn-type structure) is a bulk superconductor with a transition temperature of about 2.06 K and an upper critical field μ{sub 0}H{sub C2}(0){sup WHH} of 1.2 T, whereas no superconducting transition has been observed up to 0.3 K in Pt{sub 9}Cu{sub 3}B{sub 5} (Pt{sub 9}Zn{sub 3}B{sub 5–δ}-type structure) from electrical resistivity measurements. - Highlights: • First two copper platinum borides, (Pt{sub 0.67}Cu{sub 0.33}){sub 3}Cu{sub 2}B and Pt{sub 9}Cu{sub 3}B{sub

  20. Synthesis, crystal structure and magnetic properties of Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Kokal, I. [Koç University, Rumelifeneri Yolu, Sariyer, Istanbul 34450 (Turkey); Aydemir, U., E-mail: uaydemir@ku.edu.tr [Koç University, Rumelifeneri Yolu, Sariyer, Istanbul 34450 (Turkey); Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str.40, Dresden 01187 (Germany); Prots, Yu.; Förster, T.; Sichelschmidt, J. [Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str.40, Dresden 01187 (Germany); Yahyaoglu, M. [Koç University, Rumelifeneri Yolu, Sariyer, Istanbul 34450 (Turkey); Auffermann, G.; Schnelle, W. [Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str.40, Dresden 01187 (Germany); Schappacher, F.; Pöttgen, R. [Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstraße 30, Münster 48149 (Germany); Somer, M., E-mail: msomer@ku.edu.tr [Koç University, Rumelifeneri Yolu, Sariyer, Istanbul 34450 (Turkey)

    2014-02-15

    Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}] was synthesized from the metathesis reaction of Li{sub 3}[BN{sub 2}] and EuCl{sub 3} at 850 °C. Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}] crystallizes in the trigonal space group R3{sup ¯}c (No. 167) with a=12.0225(2) Å, c=6.8556(2) Å and Z=6. In the crystal structure, isolated, planar cyclic [B{sub 3}N{sub 6}]{sup 9−} units are charge-balanced by the mixed-valence Eu{sup 3+}/Eu{sup 2+} and Li{sup +} cations. Li{sup +} occupies partially (44%) the Wyckoff site 6b and is sandwiched between the [B{sub 3}N{sub 6}]{sup 9−} anions. Mössbauer spectroscopy results show the resonance lines of Eu{sup 2+} and Eu{sup 3+}, respectively, indicating the heterogeneous mixed valency of the Eu atoms. X-Band ESR investigations between 5 and 300 K reveal an intense signal over the whole temperature range originating from Eu{sup 2+}. Magnetic susceptibility measurements indicate a Curie–Weiss behavior with an experimental effective magnetic moment of μ{sub eff}=8.28 μ{sub B} per formula unit. - Graphical abstract: Single crystals of Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}] was obtained from the metathesis reaction of Li{sub 3}[BN{sub 2}] and EuCl{sub 3.}{sup 151}Eu Mössbauer, ESR and magnetic susceptibility measurements reveal the heterogeneous mixed valency of the Eu atoms. Display Omitted - Highlights: • Single crystals of Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}] was obtained from the metathesis reaction of Li{sub 3}[BN{sub 2}] and EuCl{sub 3} at 850 °C. • Crystal structure is built up by isolated, planar cyclic [B{sub 3}N{sub 6}]{sup 9−} units which are surrounded by mixed valence Eu{sup 3+}/Eu{sup 2+}. • Li{sup +} occupies partially (44%) the site 6b and is sandwiched between the [B{sub 3}N{sub 6}]{sup 9−} anions. • The {sup 151}Eu Mössbauer spectroscopy, electron spin resonance spectroscopy and magnetic susceptibility measurements confirm the heterogeneous mixed valency of Eu.

  1. Thermodynamic analysis of binary Fe{sub 85}B{sub 15} to quinary Fe{sub 85}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 1} alloys for primary crystallizations of α-Fe in nanocrystalline soft magnetic alloys

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, A., E-mail: takeuchi@imr.tohoku.ac.jp; Zhang, Y.; Takenaka, K.; Makino, A. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2015-05-07

    Fe-based Fe{sub 85}B{sub 15}, Fe{sub 84}B{sub 15}Cu{sub 1}, Fe{sub 82}Si{sub 2}B{sub 15}Cu{sub 1}, Fe{sub 85}Si{sub 2}B{sub 12}Cu{sub 1}, and Fe{sub 85}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 1} (NANOMET{sup ®}) alloys were experimental and computational analyzed to clarify the features of NANOMET that exhibits high saturation magnetic flux density (B{sub s}) nearly 1.9 T and low core loss than conventional nanocrystalline soft magnetic alloys. The X-ray diffraction analysis for ribbon specimens produced experimentally by melt spinning from melts revealed that the samples were almost formed into an amorphous single phase. Then, the as-quenched samples were analyzed with differential scanning calorimeter (DSC) experimentally for exothermic enthalpies of the primary and secondary crystallizations (ΔH{sub x1} and ΔH{sub x2}) and their crystallization temperatures (T{sub x1} and T{sub x2}), respectively. The ratio ΔH{sub x1}/ΔH{sub x2} measured by DSC experimentally tended to be extremely high for the Fe{sub 85}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 1} alloy, and this tendency was reproduced by the analysis with commercial software, Thermo-Calc, with database for Fe-based alloys, TCFE7 for Gibbs free energy (G) assessments. The calculations exhibit that a volume fraction (V{sub f}) of α-Fe tends to increase from 0.56 for the Fe{sub 85}B{sub 15} to 0.75 for the Fe{sub 85}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 1} alloy. The computational analysis of the alloys for G of α-Fe and amorphous phases (G{sub α-Fe} and G{sub amor}) shows that a relationship G{sub α-Fe} ∼ G{sub amor} holds for the Fe{sub 85}Si{sub 2}B{sub 12}Cu{sub 1}, whereas G{sub α-Fe} < G{sub amor} for the Fe{sub 85}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 1} alloy at T{sub x1} and that an extremely high V{sub f} = 0.75 was achieved for the Fe{sub 85}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 1} alloy by including 2.8 at. % Si and 4.5 at. % P into α-Fe. These computational results indicate that the Fe{sub 85}Si{sub 2}B{sub

  2. Effect of bias voltage on tunneling mechanism in Co{sub 40}Fe{sub 40}B{sub 20}/MgO/Co{sub 40}Fe{sub 40}B{sub 20} pseudo-spin valve

    Energy Technology Data Exchange (ETDEWEB)

    Yıldırım, Mustafa; Öksüzoğlu, Ramis Mustafa, E-mail: rmoksuzoglu@anadolu.edu.tr

    2015-04-01

    Bias voltage dependence of tunneling mechanism has been systematically investigated in Co{sub 40}Fe{sub 40}B{sub 20} (2.1 nm)/MgO (2 nm)/Co{sub 40}Fe{sub 40}B{sub 20} (1.7 nm) pseudo-spin valve magnetic tunnel junction deposited using the combination of the pulsed DC unbalanced magnetron and RF magnetron sputtering techniques. Structural investigations revealed polycrystalline and partially (001) oriented growth of CoFeB/MgO(001) MTJ with similar low interface roughness on both side of the MgO barrier. The junction with a 25×25 µm{sup 2} area indicates a giant tunnel magnetoresistance in the order of 505% at room temperature. The magnetoresistance ratio decreases with increasing applied bias voltage ranging from 0.5 to 1.8 V. Reasonable values for barrier thickness and heights were obtained using the combination of Brinkman and Gundlach models, including average barrier height and symmetry. Both barrier parameters and the tunneling mechanism vary in dependence of applied bias voltage. The tunneling mechanism indicates a change from direct to the FN tunneling, especially when reaching high bias voltages. Effect of the tunneling mechanism on the bias dependence of the magnetoresistance was also discussed. - Highlights: • Polycrystalline and partially (001) oriented CoFeB/MgO MTJ with similar interface roughness was produced. • TMR ratio of 505% was obtained at room temperature, decreasing with increasing bias. • Similar interface roughness with low barrier asymmetry results in high TMR ratio. • Tunneling mechanism changes from direct to Fowler–Nordheim for applied biases >0.8 V. • Bias dependence of TMR is correlated with change of the tunneling mechanism.

  3. Observations of B{sub s}{sup 0}→ψ(2S)η and B{sub (s)}{sup 0}→ψ(2S)π{sup +}π{sup −} decays

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [Fakultät Physik, Technische Universität Dortmund, Dortmund (Germany); Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amerio, S. [Sezione INFN di Padova, Padova (Italy); Amhis, Y. [LAL, Université Paris-Sud, CNRS/IN2P3, Orsay (France); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universität Zürich, Zürich (Switzerland); Andreassen, R. [University of Cincinnati, Cincinnati, OH (United States); and others

    2013-06-21

    First observations of the B{sub s}{sup 0}→ψ(2S)η, B{sup 0}→ψ(2S)π{sup +}π{sup −} and B{sub s}{sup 0}→ψ(2S)π{sup +}π{sup −} decays are made using a dataset corresponding to an integrated luminosity of 1.0 fb{sup −1} collected by the LHCb experiment in proton–proton collisions at a centre-of-mass energy of √(s)=7 TeV. The ratios of the branching fractions of each of the ψ(2S) modes with respect to the corresponding J/ψ decays are (B(B{sub s}{sup 0}→ψ(2S)η))/(B(B{sub s}{sup 0}→J/ψη)) =0.83±0.14(stat)±0.12(syst)±0.02(B), (B(B{sup 0}→ψ(2S)π{sup +}π{sup −}))/(B(B{sup 0}→J/ψπ{sup +}π{sup −})) =0.56±0.07(stat)±0.05(syst)±0.01(B), (B(B{sub s}{sup 0}→ψ(2S)π{sup +}π{sup −}))/(B(B{sub s}{sup 0}→J/ψπ{sup +}π{sup −})) =0.34±0.04(stat)±0.03(syst)±0.01(B), where the third uncertainty corresponds to the uncertainties of the dilepton branching fractions of the J/ψ and ψ(2S) meson decays.

  4. First observation of the decay B{sub s}{sup 0}{yields}K{sup Low-Asterisk 0}K{sup Macron Low-Asterisk 0}

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adeva, B., E-mail: Bernardo.Adeva@usc.es [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); Archilli, F. [Laboratori Nazionali dell' INFN di Frascati, Frascati (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Collaboration: LHCb Collaboration; and others

    2012-03-13

    The first observation of the decay B{sub s}{sup 0}{yields}K{sup Low-Asterisk 0}K{sup Macron Low-Asterisk 0} is reported using 35 pb{sup -1} of data collected by LHCb in proton-proton collisions at a centre-of-mass energy of 7 TeV. A total of 49.8{+-}7.5B{sub s}{sup 0}{yields}(K{sup +}{pi}{sup -})(K{sup -}{pi}{sup +}) events are observed within {+-}50 MeV/c{sup 2} of the B{sub s}{sup 0} mass and 746 MeV/c{sup 2}B{sub s}{sup 0}{yields}K{sup Low-Asterisk 0}K{sup Macron Low-Asterisk 0} signal. The branching fraction and the CP-averaged K{sup Low-Asterisk 0} longitudinal polarization fraction are measured to be B(B{sub s}{sup 0}{yields}K{sup Low-Asterisk 0}K{sup Macron Low-Asterisk 0})=(2.81{+-}0.46(stat.){+-}0.45(syst.){+-}0.34(f{sub s}/f{sub d})) Multiplication-Sign 10{sup -5} and f{sub L}=0.31{+-}0.12(stat.){+-}0.04(syst.).

  5. Potential NRQCD for unequal masses and the B{sub c} spectrum at N{sup 3}LO

    Energy Technology Data Exchange (ETDEWEB)

    Peset, Clara; Pineda, Antonio [Barcelona Univ. Autonoma (Spain). Dept. Fisica y IFAE-BIST; Stahlhofen, Maximilian [DESY Hamburg (Germany). Theory Group; Mainz Univ. (Germany). PRISMA Cluster of Excellence

    2015-11-15

    We determine the 1/m and 1/m{sup 2} spin-independent heavy quarkonium potentials in the unequal mass case with O(α{sup 3}) and O(α{sup 2}) accuracy, respectively. We discuss in detail different methods to calculate the potentials, and show the equivalence among them. In particular we obtain, for the first time, the manifestly gauge invariant 1/m and 1/m{sup 2} potentials in terms of Wilson loops with next-to-leading order (NLO) precision. As an application of our results we derive the theoretical expression for the B{sub c} spectrum in the weak-coupling limit through next-to-next-to-next-to-leading order (N{sup 3}LO).

  6. Evidence for the decay B{sup 0}{yields}J/{psi}{omega} and measurement of the relative branching fractions of B{sub s}{sup 0} meson decays to J/{psi}{eta} and J/{psi}{eta}{sup Prime}

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adametz, A. [Physikalisches Institut, Ruprecht-Karls-Universitaet Heidelberg, Heidelberg (Germany); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); and others

    2013-02-21

    First evidence of the B{sup 0}{yields}J/{psi}{omega} decay is found and the B{sub s}{sup 0}{yields}J/{psi}{eta} and B{sub s}{sup 0}{yields}J/{psi}{eta}{sup Prime} decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb{sup -1} collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of {radical}(s)=7 TeV. The branching fractions of these decays are measured relative to that of the B{sup 0}{yields}J/{psi}{rho}{sup 0} decay: (B(B{sup 0}{yields}J/{psi}{omega}))/(B(B{sup 0}{yields}J/{psi}{rho}{sup 0})) =0.89{+-}0.19(stat){sub -0.13}{sup +0.07}(syst), (B(B{sub s}{sup 0}{yields}J/{psi}{eta}))/(B(B{sup 0}{yields}J/{psi}{rho}{sup 0})) =14.0{+-}1.2(stat){sub -1.5}{sup +1.1}(syst){sub -1.0}{sup +1.1}((f{sub d})/(f{sub s}) ), (B(B{sub s}{sup 0}{yields}J/{psi}{eta}{sup Prime }))/(B(B{sup 0}{yields}J/{psi}{rho}{sup 0})) =12.7{+-}1.1(stat){sub -1.3}{sup +0.5}(syst){sub -0.9}{sup +1.0}((f{sub d})/(f{sub s}) ), where the last uncertainty is due to the knowledge of f{sub d}/f{sub s}, the ratio of b-quark hadronization factors that accounts for the different production rate of B{sup 0} and B{sub s}{sup 0} mesons. The ratio of the branching fractions of B{sub s}{sup 0}{yields}J/{psi}{eta}{sup Prime} and B{sub s}{sup 0}{yields}J/{psi}{eta} decays is measured to be (B(B{sub s}{sup 0}{yields}J/{psi}{eta}{sup Prime }))/(B(B{sub s}{sup 0}{yields}J/{psi}{eta})) =0.90{+-}0.09(stat){sub -0.02}{sup +0.06}(syst).

  7. Search for B{sub s}{sup 0}→μ{sup +}μ{sup −} and B{sup 0}→μ{sup +}μ{sup −} decays in CMS

    Energy Technology Data Exchange (ETDEWEB)

    Tinti, Gemma, E-mail: gemma.tinti@psi.ch [Department of Physics and Astronomy, University of Kansas, Lawrence, KS (United States)

    2012-12-15

    The rare decays B{sub s}{sup 0}→μ{sup +}μ{sup −} and B{sup 0}→μ{sup +}μ{sup −} are potentially sensitive to physics beyond the Standard Model as their branching fraction can be highly enhanced in new physics models. The CMS experiment at the LHC has already reported the studies of these rare decays in pp collisions at √(s)=7TeV, corresponding to an integrated luminosity of 5fb{sup −1}. In both decays, the number of observed events is consistent with the expectation from background plus Standard Model signal prediction. Results of the combination of the exclusion limits for two rare decays in different LHC experiments will also be presented.

  8. Effect of leaching in Na{sub 2}O-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-SiO{sub 2} system glass on borate anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myeong Jeong; Lee, Byung Chul; Ryu, Bong Ki [Pusan National Univ., Pusan(Korea, Republic of); Choi, Jong Rak; Kim, Cheon Woo; Park, Jong Kil; Shin, Sang Woon; Ha, Jong Hyun; Song, Myung Jae [Korea Hydro and Nuclear Power Co., Taejon (Korea, Republic of)

    2003-07-01

    Vitrification is an attractive approach for treatment of the radioactive waste from nuclear power plants. The borosilicate glass has received major consideration as the primary waste form for the disposal of the radioactive waste. In this study, we examined Na{sub 2}O-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-SiO{sub 2} system glass as radioactive waste glass. The quantitative analysis by ICP for leached solution has shown that the more SiO{sub 2} in glass decrease the leaching rate from the glass. It was found that higher BO{sub 4} tetrahedra structure leads to increase the chemical durability.

  9. Wire-length effect on GMI in Co{sub 70.3}Fe{sub 3.7}B{sub 10}Si{sub 13}Cr{sub 3} amorphous glass-coated microwires

    Energy Technology Data Exchange (ETDEWEB)

    Qin, F.X., E-mail: faxiang.qin@bristol.ac.u [Advanced Composite Center for Innovation and Science, Department of Aerospace Engineering, University of Bristol, University Walk, Bristol BS8 1TR (United Kingdom); Peng, H.X. [Advanced Composite Center for Innovation and Science, Department of Aerospace Engineering, University of Bristol, University Walk, Bristol BS8 1TR (United Kingdom); Phan, M.H. [Department of Physics, University of South Florida, Tampa, FL 33620 (United States)

    2010-03-15

    The sample length dependence of giant magnetoimpedance (GMI) in Co{sub 70.3}Fe{sub 3.7}B{sub 10}Si{sub 13}Cr{sub 3} amorphous glass-coated microwires has been studied experimentally and theoretically in the frequency range of 1-10 MHz. It has been shown that there exists a critical microwire length, below which the GMI effect is favored in shorter microwires and above which longer microwires possess a more sensitive dependence of the real component of the impedance to the frequency variation. It is demonstrated that once the resistance of the microwires of varied length is determined, it is possible to evaluate the change in GMI profiles with respect to the change of wire length. The simplified skin-effect model has been found to well explain the observed behaviors.

  10. Synthesis, crystal structure, spectrum properties, and electronic structure of a new three-borate Ba{sub 4}Na{sub 2}Zn{sub 4}(B{sub 3}O{sub 6}){sub 2}(B{sub 12}O{sub 24}) with two isolated types of blocks: 3[3Δ] and 3[2Δ + 1T

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xuean, E-mail: xueanchen@bjut.edu.cn [College of Materials Science and Engineering, Beijing University of Technology, Ping Le Yuan 100, Beijing 100124 (China); Chen, Yanjun; Sun, Chong; Chang, Xinan [College of Materials Science and Engineering, Beijing University of Technology, Ping Le Yuan 100, Beijing 100124 (China); Xiao, Weiqiang [Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing 100124 (China)

    2013-08-15

    Graphical abstract: Ba{sub 4}Na{sub 2}Zn{sub 4}(B{sub 3}O{sub 6}){sub 2}(B{sub 12}O{sub 24}) contains complicated porous anionic layers composed of ZnO{sub 4} tetrahedra, [B{sub 3}O{sub 6}]{sup 3−} rings with notation of 3[3Δ], and [B{sub 12}O{sub 24}]{sup 12−} groups built up from four BO{sub 4} tetrahedra and eight BO{sub 3} triangles with notation of 2 × {2 × (3[2Δ + 1T])}. The anionic layers stack along c-axis, with the intralayer open channels and interlayer void spaces occupied by Na{sup +} or Ba{sup 2+} cations to balance charge. Highlights: •Ba{sub 4}Na{sub 2}Zn{sub 4}(B{sub 3}O{sub 6}){sub 2}(B{sub 12}O{sub 24}) has been prepared by solid state reaction method. •It has a layered structure consisting of ZnO{sub 4} tetrahedra, [B{sub 3}O{sub 6}]{sup 3−} rings, and [B{sub 12}O{sub 24}]{sup 12−} groups. •The IR spectrum confirmed the presence of both BO{sub 3} and BO{sub 4} groups. •UV–vis diffuse reflectance spectrum revealed a band gap of about 3.13 eV. •Band structure calculations indicated that it is an indirect band material. -- Abstract: A new barium sodium zincoborate, Ba{sub 4}Na{sub 2}Zn{sub 4}(B{sub 3}O{sub 6}){sub 2}(B{sub 12}O{sub 24}), has been prepared by solid state reaction method below 750 °C. Single-crystal XRD analysis showed that it crystallizes in the triclinic space group P1{sup ¯} with a = 7.0288(14) Å, b = 7.0687(14) Å, c = 17.501(4) Å, α = 91.92(3)°, β = 96.46(3)°, γ = 119.72(3)°, Z = 1. The crystal structure exhibits complicated porous anionic layers composed of ZnO{sub 4} tetrahedra, [B{sub 3}O{sub 6}]{sup 3−} rings with notation of 3[3Δ], and [B{sub 12}O{sub 24}]{sup 12−} groups built up from four BO{sub 4} tetrahedra and eight BO{sub 3} triangles with notation of 2 × {2 × (3[2Δ + 1T])}. The anionic layers stack along c-axis, with the intralayer open channels and interlayer void spaces occupied by Na{sup +} or Ba{sup 2+} cations to balance charge. The IR spectrum further confirmed the

  11. Measurement of the B{sub s}{sup 0}-B{sup Macron }{sub s}{sup 0} oscillation frequency {Delta}m{sub s} in B{sub s}{sup 0}{yields}D{sub s}{sup -}(3){pi} decays

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); Archilli, F. [Laboratori Nazionali dell' INFN di Frascati, Frascati (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Arrabito, L. [CC-IN2P3, CNRS/IN2P3, Lyon-Villeurbanne (France); Artamonov, A. [Institute for High Energy Physics (IHEP), Protvino (Russian Federation); and others

    2012-03-19

    The B{sub s}{sup 0}-B{sup Macron }{sub s}{sup 0} oscillation frequency {Delta}m{sub s} is measured with 36 pb{sup -1} of data collected in pp collisions at {radical}(s)=7 TeV by the LHCb experiment at the Large Hadron Collider. A total of 1381 B{sub s}{sup 0}{yields}D{sub s}{sup -}{pi}{sup +} and B{sub s}{sup 0}{yields}D{sub s}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +} signal decays are reconstructed, with average decay time resolutions of 44 fs and 36 fs, respectively. An oscillation signal with a statistical significance of 4.6{sigma} is observed. The measured oscillation frequency is {Delta}m{sub s}=17.63{+-}0.11(stat){+-}0.02(syst) ps{sup -1}.

  12. High prevalence of mild hyperhomocysteinemia and folate, B/sub 12/ and B/sub 6/ deficiencies in an urban population in Karachi, Pakistan

    International Nuclear Information System (INIS)

    To find out the prevalence of hyperhomocysteinemia, and deficiencies of folate, vitamin B6 and vitamin B12 in an urban population in Karachi, Pakistan. Methodology: In a pre and post experimental study, eight hundred and seventy-two apparently healthy adults (aged 18-60 years; 355 males and 517 females) were recruited from a low-income urban locality in East of Karachi from February 2006 to March 2007. Fasting venous blood was obtained. Serum was analyzed for folate and vitamin B12. Plasma was analyzed for pyridoxal phosphate (PLP, co enzymic form of B6) and total homocysteine. A group of vitamin-deficient individuals (n=194) was given 3-week supplementation with folic acid (5mg/ day), methylcobalamin (0.5mg/day) and pyridoxine hydrochloride (vitamin B6, 50 mg/day). After supplementation, serum/plasma levels of folate, vitamin B12, PLP and homocysteine were again determined. Prevalence of hyperhomocysteinemia (>15 mu mol/l) was 32%. Similarly percent values of folate deficiency (<3.5ng/ml), vitamin B6 deficiency (PLP<20 nmol/l) and vitamin B12 deficiency (<200pg/ml) in the study population were 27.5%, 33.7% and 9.74%, respectively. Hyperhomocysteinemia was associated with male sex, folate deficiency, vitamin B12 deficiency [OR (95%CI), 8.3(5.7-12.1); 2.5(1.76-3.58); 2.6(1.5-4.5), respectively]. A 3-week supplementation with folic acid, methylcobalamin and pyridoxine hydrochloride in vitamin deficient subjects decreased plasma homocysteine levels by 37%. High prevalence estimates of folate, vitamin B12, and vitamin B6 deficiencies appear to be the major determinants of hyperhomocysteinemia in a low income general population in Karachi. (author)

  13. Effective lifetime measurements in the B{sub s}{sup 0}→K{sup +}K{sup −}, B{sup 0}→K{sup +}π{sup −} and B{sub s}{sup 0}→π{sup +}K{sup −} decays

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [Fakultät Physik, Technische Universität Dortmund, Dortmund (Germany); Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amerio, S. [Sezione INFN di Padova, Padova (Italy); Amhis, Y. [LAL, Université Paris-Sud, CNRS/IN2P3, Orsay (France); An, L. [Center for High Energy Physics, Tsinghua University, Beijing (China); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universität Zürich, Zürich (Switzerland); Andreassen, R. [University of Cincinnati, Cincinnati, OH (United States); Andreotti, M. [Sezione INFN di Ferrara, Ferrara (Italy); and others

    2014-09-07

    Measurements of the effective lifetimes in the B{sub s}{sup 0}→K{sup +}K{sup −}, B{sup 0}→K{sup +}π{sup −} and B{sub s}{sup 0}→π{sup +}K{sup −} decays are presented using 1.0 fb{sup −1} of pp collision data collected at a centre-of-mass energy of 7 TeV by the LHCb experiment. The analysis uses a data-driven approach to correct for the decay time acceptance. The measured effective lifetimes are τ{sub B{sub s{sup 0}→K{sup +}K{sup −}}}=1.407±0.016(stat)±0.007(syst) ps, τ{sub B{sup 0}→K{sup +}π{sup −}}=1.524±0.011(stat)±0.004(syst) ps, τ{sub B{sub s{sup 0}→π{sup +}K{sup −}}}=1.60±0.06(stat)±0.01(syst) ps. This is the most precise determination to date of the effective lifetime in the B{sub s}{sup 0}→K{sup +}K{sup −} decay and provides constraints on contributions from physics beyond the Standard Model to the B{sub s}{sup 0} mixing phase and the width difference ΔΓ{sub s}.

  14. Anomalous behavior of B{sub 1g} mode in highly transparent anatase nano-crystalline Nb-doped Titanium Dioxide (NTO) thin films

    Energy Technology Data Exchange (ETDEWEB)

    Gautam, Subodh K., E-mail: subodhkgtm@gmail.com, E-mail: fouran@gmail.com; Ojha, S.; Singh, Fouran, E-mail: subodhkgtm@gmail.com, E-mail: fouran@gmail.com [Material Science Group, Inter University Accelerator Centre, New Delhi -110067 (India); Gautam, Naina [Department of Electronic Science, University of Delhi South Campus, New Delhi - 110023 (India); Singh, R. G. [Department of Physics, Bhagini Nivedita College, Delhi University, Delhi– 110043 (India); Shukla, D. K. [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452017 (India)

    2015-12-15

    The effect of Niobium doping and size of crystallites on highly transparent nano-crystalline Niobium doped Titanium Dioxide (NTO) thin films with stable anatase phase are reported. The Nb doping concentration is varied within the solubility limit in TiO{sub 2} lattice. Films were annealed in controlled environment for improving the crystallinity and size of crystallites. Elemental and thickness analysis were carried out using Rutherford backscattering spectrometry and cross sectional field emission scanning electron microscopy. Structural characteristics reveal a substitutional incorporation of Nb{sup +5} in the TiO{sub 2} lattice which inhibits the anatase crystallites growth with increasing the doping percentage. The micro-Raman (MR) spectra of films with small size crystallites shows stiffening of about 4 cm{sup −1} for the E{sub g(1)} mode and is ascribed to phonon confinement and non-stoichiometry. In contrast, B{sub 1g} mode exhibits a large anomalous softening of 20 cm{sup −1} with asymmetrical broadening; which was not reported for the case of pure TiO{sub 2} crystallites. This anomalous behaviour is explained by contraction of the apical Ti-O bonds at the surface upon substitutional Nb{sup 5+} doping induced reduction of Ti{sup 4+} ions also known as hetero-coordination effect. The proposed hypotheses is manifested through studying the electronic structure and phonon dynamics by performing the near edge x-ray absorption fine structure (NEXAFS) and temperature dependent MR down to liquid nitrogen temperature on pure and 2.5 at.% doped NTO films, respectively.

  15. Iodine-123-metaiodobenzylguanidine cardiac scintigraphy in patients with diabetes mellitus. Therapeutic effects of aldose reductase inhibitor and vitamin B{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Utsunomiya, Keita [Osaka Medical Coll., Takatsuki (Japan)

    1997-12-01

    Twenty normal volunteers (C group) and 56 patients with non-insulin-dependent diabetes mellitus (NIDDM) who did not have ischemic heart diseases (DM group), were evaluated by means of iodine-123-metaiodobenzylguanidine (MIBG) scintigraphy. The uptake ratio between the cardiac muscle and the upper mediastinum was calculated. The ratio determined from the initial I-123-MIBG scintigraphy image was expressed as HMi, and that determined from the delayed image was expressed as HMd. The washout rate percentage (%WR) was calculated. At least one instance of either the HMi, the HMd, or %WR was outside the mean{+-}1 standard deviation of C group in 34 DM group patients. Aldose reductase inhibitor (ARI) was administered to 17 of the 34 patients and Vitamin B{sub 12} (VB{sub 12}) to the remaining 17 patients, for 3 to 5 months. Before and after treatment, scintigraphic studies with I-123-MIBG were carried out, and the HMi, HMd, and %WR were calculated. There were no significant differences found in FBG, HbA1c, or 1.5-AG levels after treatment with either drug, when compared to the pretreatment values. Both HMi and HMd in the DM group were significantly lower, and %WR was significantly higher than in the C group. The changes in HMi, HMd, and %WR after treatment with ARI were not significant. After treatment with VB{sub 12}, the HMi and HMd levels were significantly increased (p<0.01). Thus, measurement of myocardial MIBG accumulation is a promising new method to detect cardiac sympathetic denervation in diabetic patients. With these changes in treatment, VB{sub 12} was shown to be effective for improvement of HMi and HMd in NIDDM. (author)

  16. Effects of aldose reductase inhibitor and vitamin B{sub 12} on myocardial uptake of iodine-123 metaiodobenzylguanidine in patients with non-insulin-dependent diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Utsunomiya, Keita; Narabayashi, Isamu [Department of Radiology, Osaka Medical College, Osaka (Japan); Tamura, Koji; Nakatani, Yuko; Saika, Yoshinori; Onishi, Satoshi; Kariyone, Shigeo [Department of Radiology, Internal Medicine and Surgery, Keihanna Hospital, Osaka (Japan)

    1998-12-01

    This study was undertaken to examine the effects of aldose reductase inhibitor (ARI) and vitamin B{sub 12} (VB12) on myocardial uptake of iodine-123 metaiodobenzylguanidine (MIBG) in patients with diabetic autonomic disorder. Myocardial scintigraphy using {sup 123}I-MIBG was performed on 20 healthy volunteers (controls) and 56 patients with non-insulin-dependent diabetes mellitus (NIDDM), in order to obtain the heart/mediastinum ratio in the initial (HMi) and the delayed images (HMd), and the washout rate (%WR). Thirty-four of the 56 NIDDM patients could be diagnosed as having diabetic autonomic disorder by evaluating their scintigraphic findings in comparison with the controls. Seventeen of these 34 patients received 150 mg/day of epalrestat (ARI group) in three divided doses before meals, and the other 17 received 1.5 mg/day of mecobalamin (VB12 group) in three divided doses after meals, for 3-5 months. According to the presence or absence of clinical symptoms of autonomic or peripheral somatic nerve disorder, the patients were subclassified into four groups. group 1=patients, with autonomic symptoms or somatosensory disorder in the ARI group; group 2=patients without autonomic symptoms or somatosensory disorder in the ARI group; group 3=patients with autonomic symptoms or somatosensory disorder in the VB12 group; and group 4=patients without autonomic symptoms or somatosensory disorder in the VB12 group. After completion of the treatment, myocardial scintigraphy was performed again. Comparing the results obtained before and after the treatment, it was seen that ARI improved only the HMi in group 1 (P=0.046), whereas VB12 significantly improved HMi in the group 3 (P=0.018) and HMi, HMd and %WR in group 4 (P=0.043, P=0.018 and P=0.043, respectively). We conclude that VB12 is more efficacious than ARI in the treatment of diabetic cardiovascular autonomic disorder. (orig.) With 2 figs., 3 tabs., 23 refs.

  17. anti B{sup 0}, B{sup -} and anti B{sub s}{sup 0} decays into J/ψ and K anti K or πη

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Wei-Hong [Guangxi Normal University, Department of Physics, Guilin (China); Xie, Ju-Jun [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Beijing (China); Oset, E. [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Centro Mixto Universidad de Valencia-CSIC Institutos de Investigacion de Paterna, Departamento de Fisica Teorica y IFIC, Valencia (Spain)

    2015-12-15

    We study the anti B{sub s}{sup 0} → J/ψK{sup +}K{sup -}, anti B{sup 0} → J/ψK{sup +}K{sup -}, B{sup -} → J/ψK{sup 0}K{sup -}, anti B{sup 0} → J/ψπ{sup 0}η and B{sup -} → J/ψπ{sup -}η decays and compare their mass distributions with those obtained for the anti B{sub s}{sup 0} → J/ψπ{sup +}π{sup -} and anti B{sup 0} → J/ψπ{sup +}π{sup -}. The approach followed consist in a factorization of the weak part and the hadronization part into a factor which is common to all the processes. Then what makes the reactions different are some trivial Cabibbo-Kobayashi-Maskawa matrix elements and the weight by which the different pairs of mesons appear in a primary step plus their final state interaction. These elements are part of the theory and thus, up to a global normalization factor, all the invariant mass distributions are predicted with no free parameters. Comparison is made with the limited experimental information available. Further comparison of these results with coming LHCb measurements will be very valuable to make progress in our understanding of the meson.meson interaction and the nature of the low lying scalar meson resonances, f{sub 0}(500), f{sub 0}(980) and a{sub 0}(980). (orig.)

  18. Structure-Function of the Cytochrome b>6f Complex of Oxygenic Photosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, W. A.; Yamashita, E.; Baniulis, D.; Whitelegge, J.; Hasan, S. S. [Lithuanian RAF; (UCLA); (Purdue); (Osaka)

    2014-03-20

    Structure–function of the major integral membrane cytochrome b>6f complex that functions in cyanobacteria, algae, and green plants to transfer electrons between the two reaction center complexes in the electron transport chain of oxygenic photosynthesis is discussed in the context of recently obtained crystal structures of the complex and soluble domains of cytochrome f and the Rieske iron–sulfur protein. The energy-transducing function of the complex, generation of the proton trans-membrane electrochemical potential gradient, centers on the oxidation/reduction pathways of the plastoquinol/plastoquinone (QH2/Q), the proton donor/acceptor within the complex. These redox reactions are carried out by five redox prosthetic groups embedded in each monomer, the high potential two iron–two sulfur cluster and the heme of cytochrome f on the electropositive side (p) of the complex, two noncovalently bound b-type hemes that cross the complex and the membrane, and a covalently bound c-type heme (cn) on the electronegative side (n). These five redox-active groups are organized in high- (cyt f/[2Fe–2S] and low-potential (hemes bp, bn, cn) electron transport pathways that oxidize and reduce the quinol and quinone on the p- and n-sides in a Q-cycle-type mechanism, while translocating as many as 2 H+ to the p-side aqueous side for every electron transferred through the high potential chain to the photosystem I reaction center. The presence of heme cn and the connection of the n-side of the membrane and b>6f complex to the cyclic electron transport chain indicate that the Q cycle in the oxygenic photosynthetic electron transport chain differs from those connected to the bc1 complex in the mitochondrial respiratory chain and the chain in photosynthetic bacteria. Inferences from the structure and C2 symmetry of the complex for the pathway of QH2/Q transfer

  19. Synergies of the decays B{sub s} → K{sup *-} l{sup +}ν and B → K* l{sup +}l{sup -}

    Energy Technology Data Exchange (ETDEWEB)

    Feldmann, Thorsten; Mueller, Bastian; Dyk, Danny van [Universitaet Siegen (Germany)

    2015-07-01

    In light of the tension between inclusive and exclusive determinations of the CKM matrix element vertical stroke V{sub ub} vertical stroke, we investigate with the decay B{sub s} → K{sup *-} l{sup +}ν an interesting, independent probe of vertical stroke V{sub ub} vertical stroke in exclusive decays. We present analytic expressions for the full angular distribution of the subsequent K{sup *-} → K{sup -}π decay. Numerical estimates are given for a subset of observables. In addition, we combine the angular observables of the decays B{sub s} → K{sup *-} l{sup +}ν and B → K* l{sup +}l{sup -} into new optimized observables, which offer the opportunity to reduce theoretical uncertainties.

  20. Microscopic changes in HoNi{sub 2}B{sub 2}C due to thermal treatment and its effect on superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Dertinger, A.; Dinnebier, R. E.; Kreyssig, A.; Stephens, P. W.; Pagola, S.; Loewenhaupt, M.; van Smaalen, S.; Braun, H. F.

    2001-05-01

    The low-temperature properties of HoNi{sub 2}B{sub 2}C strongly depend on its thermodynamic state established via thermal treatment. We present high resolution x-ray powder diffraction data taken on a pair of polycrystalline samples with identical chemical composition (HoNi{sub 2}B{sub 2.1}C) but annealed at different temperatures, namely, at 800 and at 1100{sup o}C. Their superconducting transition temperatures differ by more than 10%. Rietveld refinement and difference Fourier analysis reveal subtle differences in the atomic parameters and in the electron density on the carbon site. Furthermore, a new atomic site can be identified for both samples, which is partially occupied with the lighter atoms boron or carbon.

  1. Measurement of the polarization amplitudes and triple product asymmetries in the B{sub s}{sup 0}{yields}{phi}{phi} decay

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); Archilli, F. [Laboratori Nazionali dell' INFN di Frascati, Frascati (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); and others

    2012-07-18

    Using 1.0 fb{sup -1} of pp collision data collected at a centre-of-mass energy of {radical}(s)=7 TeV with the LHCb detector, measurements of the polarization amplitudes, strong phase difference and triple product asymmetries in the B{sub s}{sup 0}{yields}{phi}{phi} decay mode are presented. The measured values are (table)

  2. Influence of phase transformation on interfacial activity and bend sensitivity of rapidly quenched Fe{sub 77.5}Si{sub 7.5}B{sub 15}/Co{sub 72.5}Si{sub 12.5}B{sub 15} bilayered magnetostrictive ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Panda, A.K., E-mail: akpanda@nmlindia.org; Dey, Sushmita; Roy, R.K.; Singh, Satnam; Mitra, A.

    2015-03-15

    Rapidly quenched bilayer magnetostrictive ribbons have been prepared and characterized to investigate phase transformations, interfacial activity and their potentiality as bend sensors. The bilayer ribbons were processed in a way to make the positively magnetostrictive layer Fe{sub 77.5}Si{sub 7.5}B{sub 15} as the free surface while negatively magnetostrictive Co{sub 72.5}Si{sub 12.5}B{sub 15} layer as the one in contact with the quenching copper wheel. Elemental concentration profiles obtained through electron probe microanalysis (EPMA) revealed synergistic variation in Fe and Co content at the interface. Devitrification process was also observed from atomic migrations and combinations influencing the interface width. Configuration of the bent layers showed interesting bending parameter output which could be further enhanced through stress relaxation. A detrimental effect of devitrification on bend sensitivity of rapidly quenched bilayers was also displayed. - Highlights: • Melt spun bilayered ribbons of Fe{sub 77.5}Si{sub 7.5}B{sub 15} and Co{sub 72.5}Si{sub 12.5}B{sub 15} alloys were prepared. • Superior bend sensitivity in bilayered ribbons were observed through stress relief. • Synergistic Fe and Co interfacial diffusion occurred across Fe and Co alloy bilayer. • Quantitative analysis elucidates diffusion across interface zone of bilayer. • Bend sensor configuration has been suggested based on functional gradation.

  3. Effects of aldose reductase inhibitor and vitamin B{sub 12} on myocardial uptake of I-123-MIBG in patients with non-insulin-dependent diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Utsunomiya, Keita; Narabayashi, Isamu [Osaka Medical Coll., Takatsuki (Japan); Tamura, Koji; Nakaya, Yuko; Saika, Yoshinori; Kariyone, Shigeo; Ohnishi, Akira

    1998-04-01

    Based on the report that metaiodobenzylguanidine (MIBG) uptake into myocardial sympathetic nerve is useful for evaluation of diabetic heart sympathetic nerve dysfunction, authors examined the effects of epalrestat and vitamin B{sub 12} on the uptake. Subjects giving informed consent were 32 NIDDM patients without hypertensive or ischemic heart diseases on examination by {sup 201}Tl scintigraphy and others. At 10 min and 4 hr after intravenous injection of 111 MBq of {sup 123}I-MIBG, myocardial scintigraphy was performed to obtain the planar images with Siemens ZLC-370 gamma camera, whose data were processed by Shimadzu Scintipack 700 and evaluated by HM=early mean counts in heart (H)/early mean counts in mediastinum (M) and by %WR= (H-M)-(delayed H-delayed M) /(H-M). Epalrestat (150 mg/day) and vitamin B{sub 12} (1.5 mg/day) was given to each 16 patients for 3-5 months and {sup 123}I-MIBG scintigraphy was again carried out to calculate HM and %WR. As results, HM and %WR were not significantly changed by treatment with epalrestat but were improved with vitamin B{sub 12} significantly. (K.H.)

  4. Optical absorption of isotopically enriched Li{sub 2}B{sub 4}O{sub 7} single crystals irradiated by thermal neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Burak, Ya.V. E-mail: burak@ifo.lviv.ua; Adamiv, V.T.; Teslyuk, I.M.; Shevel, V.M

    2004-12-01

    Induced absorption spectra in the range 200-900 nm at 77 and 290 K for Li{sub 2}B{sub 4}O{sub 7} single crystals, isotopically Li and B enriched are presented after irradiation of these crystals by thermal neutrons with fluence 1.8x10{sup 16} cm{sup -2}. The dependence of induced absorption spectra on the isotope composition was revealed: for {sup 6}Li{sub 2}{sup 10}B{sub 4}O{sub 7} and {sup 7}Li{sub 2}{sup 10}B{sub 4}O{sub 7} crystals intensive band in the region of 280-294 nm was observed. Under substitution of {sup 7}Li isotope by {sup 6}Li in the lithium tetraborate lattice no changes in the absorption spectra were observed. The nuclear reaction {sup 10}B(n,{alpha}){sup 7}Li is proposed to be the main mechanism of formation of the radiation defects.

  5. Measurement of the B{sub s} oscillations with the semileptonic deacy B{sup 0}{sub s} {yields} D{sup -}{sub s} ({phi}{pi}{sup -}) {mu}{sup +}{nu}{sub {mu}} with the DOe detector; Messung der B{sub s}-Oszillation mit dem semileptonischen Zerfall B{sup 0}{sub s} {yields} D{sup -}{sub s} ({phi}{pi}{sup -}) {mu}{sup +}{nu}{sub {mu}} mit dem DOe-Detektor

    Energy Technology Data Exchange (ETDEWEB)

    Ay, C.

    2006-07-01

    in this thesis the measurement of B{sub s} oscillations by means of the decay B{sub s}{yields}D{sub s}{sup -}({phi}{pi}{sup -}){sub {mu}}{sup +}X at the Tevatron at a c. m. energy of {radical}(s)=1.96 TeV is described. From the results a lower limit of the oscillation frequency of {delta}m{sub s}>15.5 ps{sup -1} has been derived. (HSI)

  6. Effect of Cu addition on nanocrystallization behaviors and magnetic properties of the Fe{sub 76.5−x}C{sub 6.0}Si{sub 3.3}B{sub 5.5}P{sub 8.7}Cu{sub x} (x = 0–3 at.%) bulk metallic glass

    Energy Technology Data Exchange (ETDEWEB)

    Jung, H.Y. [Department of Materials Science and Metallurgical Engineering, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Yi, S., E-mail: yish@knu.ac.kr [Department of Materials Science and Metallurgical Engineering, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

    2013-06-05

    Highlights: ► Effect of Cu on the modification of primary phase of soft magnetic nanocrystalline alloys. ► Soft magnetic nanocrystalline alloys with amorphous precursor having high glass forming ability. ► Enhancement of glass forming ability with small amount of Cu addition. -- Abstract: The effect of Cu addition on the glass forming ability, nanocrystallization process and soft magnetic properties of the Fe{sub 76.5}C{sub 6.0}Si{sub 3.3}B{sub 5.5}P{sub 8.7} bulk metallic glass has been studied. In spite of relatively high C contents of the alloy, with only 0.5% Cu addition, the primary phase was successfully changed from metastable carbide Fe{sub 23}C{sub 6} phase to stable alpha-Fe phase and the nucleation rate at the early stage of crystallization was significantly increased. Nanocrystallization of the Fe{sub 76.0}C{sub 6.0}Si{sub 3.3}B{sub 5.5}P{sub 8.7}Cu{sub 0.5} (at.%) bulk metallic glass was studied through isothermal annealing treatments at temperature below the crystallization temperature of the alloy. With annealing at T{sub x} − 50 °C for 30 min, a large number of very fine regions (<3 nm) with ordered atomic arrangements embedded in the amorphous matrix were observed. Upon further annealing, nanocrystals of alpha-Fe phase were formed improving soft magnetic properties of the sample, which confirms the soft magnetic nanocrystallization phenomenon in Fe{sub 76.0}C{sub 6.0}Si{sub 3.3}B{sub 5.5}P{sub 8.7}Cu{sub 0.5} (at.%) bulk metallic glass. By controlling the annealing parameters as well as minor Cu contents, magnetic properties of the Fe{sub 76.5}C{sub 6.0}Si{sub 3.3}B{sub 5.5}P{sub 8.7} (at.%) bulk metallic glass were effectively optimized for practical applications.

  7. Model-based analysis of thromboxane B{sub 2} and prostaglandin E{sub 2} as biomarkers in the safety evaluation of naproxen

    Energy Technology Data Exchange (ETDEWEB)

    Sahota, Tarjinder; Sanderson, Ian; Danhof, Meindert [Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden (Netherlands); Della Pasqua, Oscar [Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden (Netherlands); Clinical Pharmacology Modelling and Simulation, GlaxoSmithKline, Uxbridge (United Kingdom)

    2014-08-01

    The assessment of safety in traditional toxicology protocols relies on evidence arising from observed adverse events (AEs) in animals and on establishing their correlation with different measures of drug exposure (e.g., C{sub max} and AUC). Such correlations, however, ignore the role of biomarkers, which can provide further insight into the underlying pharmacological mechanisms. Here we use naproxen as a paradigm drug to explore the feasibility of a biomarker-guided approach for the prediction of AEs in humans. A standard toxicology protocol was set up for the evaluation of effects of naproxen in rat, in which four doses were tested (7.5, 15, 40 and 80 mg/kg). In addition to sparse blood sampling for the assessment of exposure, thromboxane B{sub 2} and prostaglandin E{sub 2} were also collected in satellite groups. Nonlinear mixed effects modelling was used to evaluate the predictive performance of the approach. A one-compartmental model with first order absorption was found to best describe the pharmacokinetics of naproxen. A nonlinear relationship between dose and bioavailability was observed which leads to a less than proportional increase in naproxen concentrations with increasing doses. The pharmacodynamics of TXB{sub 2} and PGE{sub 2} was described by direct inhibition models with maximum pharmacological effects achieved at doses > 7.5 mg/kg. The predicted PKPD relationship in humans was within 10-fold of the values previously published. Moreover, our results indicate that biomarkers can be used to assess interspecies differences in PKPD and extrapolated data from animals to humans. Biomarker sampling should be used systematically in general toxicity studies. - Highlights: • Prediction of a drug's safety profile from preclinical protocols remains challenging. • Pharmacokinetic measures of safe exposure (e.g., AUC) ignore the role of biomarkers. • PKPD relationships enable the evaluation of adverse events in a mechanistic manner. • Major

  8. Effect of grain size on nano-indentation property of Co{sub 60}Fe{sub 20}B{sub 20} thin film

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yuan-Tsung, E-mail: ytchen@isu.edu.tw [Department of Materials Science and Engineering, I-Shou University, Kaohsiung 840, Taiwan, ROC (China); Wu, Chia-Wen [Department of Materials Science and Engineering, I-Shou University, Kaohsiung 840, Taiwan, ROC (China)

    2013-02-25

    Highlights: Black-Right-Pointing-Pointer A plane-view image was captured under a HRTEM to determine the distribution of grains. Black-Right-Pointing-Pointer The increased hardness and Young's modulus are reasonably inferred from a Hall-Petch effect. Black-Right-Pointing-Pointer Annealing increased the area of the nano-indentation triangle by SEM observation. Black-Right-Pointing-Pointer The nano-mechanical properties of the post-annealed film are worse than the as-deposited film. - Abstract: This study investigates the nano-mechanical properties of Co{sub 60}Fe{sub 20}B{sub 20} thin films and the effect of the size of the grains on them. These films were sputtered onto glass substrates to thicknesses from 1000 A to 5000 A under the following conditions: (a) substrate temperature maintained at RT, (b) post-annealing at a treatment temperature of 150 Degree-Sign C for 1 h, (c) post-annealing at a treatment temperature of 250 Degree-Sign C for 1 h, and (d) post-annealing at a treatment temperature of 350 Degree-Sign C for 1 h. A plane-view image was captured under a high-resolution transmission electron microscope (HRTEM) to determine the distribution of grains. The selected-area-diffraction (SAD) pattern was obtained using HRTEM. The electron diffraction pattern revealed that the CoFeB thin film had a nano-crystallization body-centered cubic (BCC) CoFeB structure and strong CoFeB (1 1 0) crystallization. A higher annealing temperature resulted in a larger grain. The average grain size increased with the thickness of the CoFeB thin film. The hardness and Young's modulus were obtained using nano-indentation. Results concerning the grain size and the nano-indentation measurement an increase in hardness and Young's modulus are reasonably inferred from a smaller grain size, consistent with the 'Hall-Petch' effect. The nano-indentation microstructure was obtained by scanning electron microscopy (SEM). Annealing increased the area of the nano

  9. The electronic structure, mechanical and thermodynamic properties of Mo{sub 2}XB{sub 2} and MoX{sub 2}B{sub 4} (X = Fe, Co, Ni) ternary borides

    Energy Technology Data Exchange (ETDEWEB)

    He, TianWei; Jiang, YeHua, E-mail: jiangyehua@kmust.edu.cn, E-mail: jfeng@seas.harvard.edu; Zhou, Rong [Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Feng, Jing, E-mail: jiangyehua@kmust.edu.cn, E-mail: jfeng@seas.harvard.edu [Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093 (China); School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States)

    2015-08-21

    The mechanical properties, electronic structure and thermodynamic properties of the Mo{sub 2}XB{sub 2} and MoX{sub 2}B{sub 4} (X = Fe, Co, Ni) ternary borides were calculated by first-principles methods. The elastic constants show that these ternary borides are mechanically stable. Formation enthalpy of Mo{sub 2}XB{sub 2} and MoX{sub 2}B{sub 4} (X = Fe, Co, Ni) ternary borides are at the range of −118.09 kJ/mol to −40.14 kJ/mol. The electronic structures and chemical bonding characteristics are analyzed by the density of states. Mo{sub 2}FeB{sub 2} has the largest shear and Young's modulus because of its strong chemical bonding, and the values are 204.3 GPa and 500.3 GPa, respectively. MoCo{sub 2}B{sub 4} shows the lowest degree of anisotropy due to the lack of strong direction in the bonding. The Debye temperature of MoFe{sub 2}B{sub 4} is the largest among the six phases, which means that MoFe{sub 2}B{sub 4} possesses the best thermal conductivity. Enthalpy shows an approximately linear function of the temperature above 300 K. The entropy of these compounds increase rapidly when the temperature is below 450 K. The Gibbs free energy decreases with the increase in temperature. MoCo{sub 2}B{sub 4} has the lowest Gibbs free energy, which indicates the strongest formation ability in Mo{sub 2}XB{sub 2} and MoX{sub 2}B{sub 4} (X = Fe, Co, Ni) ternary borides.

  10. Structure and crystallization behavior of La{sub 2}O{sub 3}⋅3B{sub 2}O{sub 3} metaborate glasses doped with Nd{sup 3+} or Eu{sup 3+} ions

    Energy Technology Data Exchange (ETDEWEB)

    Pytalev, D.S., E-mail: pytalev@isan.troitsk.ru [Institute of Spectroscopy, Russian Academy of Sciences, 5 Fizicheskaya St., 142190 Troitsk, Moscow (Russian Federation); Caurant, D.; Majérus, O.; Trégouët, H. [Institut de Recherche de Chimie Paris, CNRS – Chimie ParisTech, 11 Rue Pierre et Marie Curie, 75005 Paris (France); Charpentier, T. [CEA, IRAMIS, NIMBE, CEA-CNRS UMR 3299, Laboratoire de Structure et Dynamique par Résonance Magnétique, 91191 Gif-sur-Yvette (France); Mavrin, B.N. [Institute of Spectroscopy, Russian Academy of Sciences, 5 Fizicheskaya St., 142190 Troitsk, Moscow (Russian Federation)

    2015-08-25

    Highlights: • The structure and crystallization behavior of the La{sub 2}O{sub 3}⋅3B{sub 2}O{sub 3} glass are studied. • LaB{sub 3}O{sub 6} crystallizes congruently without intermediate but only from glass surface. • The structure of the amorphous and the crystalline phases differ significantly. • The activation energy of LaB{sub 3}O{sub 6} crystal growth is determined. - Abstract: The local structure and crystallization behavior of the stoichiometric La{sub 2}O{sub 3}⋅3B{sub 2}O{sub 3} (LaMB) metaborate glass doped with Nd{sup 3+} or Eu{sup 3+} ions are studied using differential thermal analysis (DTA), X-ray diffraction (XRD), Raman scattering and {sup 11}B magic-angle spinning nuclear magnetic resonance (MAS NMR), optical absorbance and luminescence techniques. In the crystallized samples, XRD, NMR and Raman spectroscopy have detected the formation of only one crystalline phase (congruent crystallization of LaB{sub 3}O{sub 6}). No intermediate metastable crystalline phase has been detected before LaB{sub 3}O{sub 6} crystals formation (single stage crystallization process). The observation of heat treated glass samples by scanning electron microscopy (SEM) and optical microscopy coupled with the study of the effect of varying the glass particle size on the DTA curves have both revealed that LaB{sub 3}O{sub 6} crystallization only occurs by a heterogeneous nucleation mechanism (needle-shape crystals) from glass surface. The activation energy E{sub c} of crystal growth has been determined by performing DTA experiments at different heating rates with the Kissinger (784 kJ/mol) and Ozawa (801 kJ/mol) equations than can be used for surface crystallization processes. The heterogeneous crystallization behavior and the spectroscopic results obtained in this work by comparing the LaMB glass with the LaB{sub 3}O{sub 6} crystalline phase suggest the existence of significant structural differences between the amorphous and the crystalline phases contrary to what

  11. Diagnosis of SDAT by HMPAO SPECT and vitamin B{sub 12} serum concentration; Diagnostik der SDAT mittels HMPAO-SPECT und Serumvitamin-B{sub 12}-Spiegel

    Energy Technology Data Exchange (ETDEWEB)

    Mikosch, P. [Landeskrankenhaus Klagenfurt (Austria). Abt. fuer Nuklearmedizin; Gallowitsch, H.J. [Landeskrankenhaus Klagenfurt (Austria). Abt. fuer Nuklearmedizin; Gomez, I. [Landeskrankenhaus Klagenfurt (Austria). Abt. fuer Nuklearmedizin; Kresnik, E. [Landeskrankenhaus Klagenfurt (Austria). Abt. fuer Nuklearmedizin; Ploeb, H. [Landeskrankenhaus Klagenfurt (Austria). Abt. fuer Nuklearmedizin; Lind, P. [Landeskrankenhaus Klagenfurt (Austria). Abt. fuer Nuklearmedizin

    1995-06-01

    It is quite difficult to confirm the diagnosis of demential disorders, including senile dementia of the Alzheimer type (SDAT) by clinical means only. Through the combination of {sup 99m}Tc-HMPAO brain SPECT and serum vitamin B{sub 12} determination it was hoped to speed up and improve the diagnosis of SDAT. 116 patients who had been divided into four groups according to their defect pattern in the {sup 99m}Tc-HMPAO brain SPECT 17 very probably had SDAT; of these 15 showed a defect pattern with brain SPECT which could be associated to SDAT. The majority of SDAT patients had serum vitamin B{sub 12} levels in the lower normal range or pathologically below that range. Both investigations contributed to establishing the SDAT diagnosis without replacing other investigations. The determination of serum vitamin B{sub 12} does not require any major additional effort. (orig.) [Deutsch] Die alleinige klinische Abklaerung dementieller Zustandsbilder, so auch der senilen Demenz vom Alzheimertyp (SDAT), ist schwierig. Durch die Kombination von {sup 99m}Tc-HMPAO-Gehirn-SPECT und Serumvitamin-B{sub 12}-Bestimmung erwarteten wir eine Beschleunigung und Verbesserung der Diagnostik der SDAT. Von 116 Patienten, die in 4 Gruppen, entsprechend ihrem {sup 99m}Tc-HMPAO-Verteilungsmuster eingeteilt worden waren, konnten bei 17 klinisch sehr wahrscheinlichen SDAT-Patienten bei 15 Auffaelligkeiten mit Hinweis auf SDAT im Gehirn SPECT gefunden werden. Ein Teil der Patienten wies einen niedrig-normalen bzw. pathologisch niedrigen Vitamin-B{sub 12}-Spiegel auf. Andere Untersuchungen wuerden durch die Kombination von Gehirn-SPECT und Serumvitamin-B{sub 12}-Bestimmung nicht ueberfluessig werden, obwohl beide Untersuchungen Informationen lieferten, die die Zuordnung zur Diagnose SDAT erleichterten. Die zusaetzliche Serumvitamin-B{sub 12}-Bestimmung stellt keinen wesentlichen Mehraufwand dar. (orig.)

  12. Microstructure evolution and mechanical properties of dissimilar friction stir welded joints between AA1100-B{sub 4}C MMC and AA6063 alloy

    Energy Technology Data Exchange (ETDEWEB)

    Guo, J. [Department of Applied Science, University of Quebec at Chicoutimi, Saguenay (QC) G7H 2B1 (Canada); Aluminium Technology Centre, National Research Council Canada, Saguenay (QC) G7H 8C3 (Canada); Gougeon, P. [Aluminium Technology Centre, National Research Council Canada, Saguenay (QC) G7H 8C3 (Canada); Chen, X.-G., E-mail: xgrant_chen@uqac.ca [Department of Applied Science, University of Quebec at Chicoutimi, Saguenay (QC) G7H 2B1 (Canada)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer Microstructures and mechanical properties of dissimilar FSW between AA1100-B{sub 4}C and AA6063 alloy. Black-Right-Pointing-Pointer Effect of the welding parameters on the interface bonding, joint microstructure and mechanical properties. Black-Right-Pointing-Pointer Microstructural evolution of dissimilar joints revealed by the electron backscatter diffraction analysis. Black-Right-Pointing-Pointer Good material mixing and seamless bonding around the interfaces between Al-B{sub 4}C and the AA6063 alloy. Black-Right-Pointing-Pointer 100% joint efficiencies (UTS) achieved by all dissimilar joints. - Abstract: The feasibility of dissimilar friction stir welding (FSW) between the AA1100-16 vol.% B{sub 4}C metal matrix composite and the AA6063 alloy has been evaluated. The effect of the welding parameters on the interface bonding, joint microstructure and mechanical properties was investigated. The results revealed that all dissimilar joints produced under welding conditions investigated were stronger than the base materials of the Al-B{sub 4}C composite. Analysis of the Mg concentration and the B{sub 4}C particle distribution indicates that good material mixing and seamless bonding was achieved around the interface between the Al-B{sub 4}C composite and the Al 6063 alloy during FSW. The electron backscatter diffraction analysis (EBSD) shows that during dissimilar FSW, there was a gradual microstructural evolution on both material sides, resulting in a variety of grain structures in the different weld zones. In the weld zones of FSW joints, the materials underwent dynamic recovery and recrystallization to different extents depending on their thermal mechanical history. The grain refinement of both materials in the nugget zone was observed. It is recommended that the 6063 aluminum alloy should be fixed on the advancing side and the use of an appropriate offset to the 6063 aluminum side is preferred.

  13. Understanding microstructural evolution and soft magnetic properties in nanocrystallized metallic glass Fe{sub 68.5}Cu{sub 1}Nb{sub 3}Si{sub 18.5}B{sub 9}

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, A. P., E-mail: apsrivas@gmail.com; Srivastava, D. [Bhabha Atomic Research Centre, Materials Science Division (India); Sharma, S. K.; Pujari, P. K. [Bhabha Atomic Research Centre, Radiochemistry Division (India); Suresh, K. G. [Indian Institute of Technology Bombay, Physics Department (India); Dey, G. K. [Bhabha Atomic Research Centre, Materials Science Division (India)

    2013-01-15

    Microstructural evolution during nanocrystallization of amorphous metallic glass Fe{sub 68.5}Si{sub 18.5}Nb{sub 3}B{sub 9}Cu{sub 1} has been studied. The effect of microstructural features of nanocrystalline phases on soft magnetic properties have been evaluated and rationalized with existing theoretical models. The TEM and XRD studies have shown the presence of single Fe{sub 3}Si nanocrystalline phase at 550 Degree-Sign C (size range 13-16 nm) and three nanocrystalline phases Fe{sub 3}Si, Fe{sub 3}B, and Fe{sub 2}B at 800 Degree-Sign C (size range 18-100 nm). Increase in annealing time at 800 Degree-Sign C resulted in decomposition of metastable Fe{sub 3}B phase to equilibrium Fe{sub 2}B phase. Positron annihilation spectroscopy revealed the presence of nanovoids in amorphous samples. Theoretical estimations showed that these nanovoids were having free volume equivalent to that of a vacancy defect consisting of five or more atoms vacancy cluster present in the amorphous samples. Nature of interfaces associated with nanocrystalline phases could be characterized using positron annihilation spectroscopy. This study showed that metallic nanoparticles have very low concentration of thermal vacancies. Effects of nature of phases, particle density, and nanoparticle size on saturation magnetization and coercivity have been studied.

  14. Tensor structure function b{sub 1}{sup d}(x,Q{sup 2}) of the deuteron at NLO and NNLO at small-x

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Saiful [R.G.I., Department of Physics, Assam, Guwahati (India); Choudhury, D.K. [Gauhati University, Department of Physics, Assam, Guwahati (India)

    2012-12-15

    The precision of the contemporary experimental data demands that the parton distribution functions (PDF's) should be corrected at least up to next-to-leading order (NLO) and preferably up to next-to-next-to-leading order (NNLO). A general form of tensor structure function b{sub 1}{sup d}(x,Q{sup 2}) of the deuteron at NLO and NNLO is obtained by using the solution of Dokshitzer, Gribov, Lipatov, Altarelli, Parisi (DGLAP) equation for singlet structure function at small-x. Results are compared with HERA Experiment data. (orig.)

  15. Synthesis and crystal structure of Ba{sub 26}B{sub 12}Si{sub 5}N{sub 27} containing [Si{sub 2}] dumbbells

    Energy Technology Data Exchange (ETDEWEB)

    Takayuki, Hashimoto [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Yamane, Hisanori, E-mail: yamane@tagen.tohoku.ac.jp [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Becker, Nils [Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen (Germany); Dronskowski, Richard [Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen (Germany); Jülich-Aachen Research Alliance, JARA-HPC, RWTH Aachen University, 52056 Aachen (Germany)

    2015-10-15

    Black, metallic luster, platelet single crystals of Ba{sub 26}B{sub 12}Si{sub 5}N{sub 27} were grown on a BN crucible wall by slowly cooling from 900 °C to 27 °C. X-ray diffraction analysis revealed that Ba{sub 26}B{sub 12}Si{sub 5}N{sub 27} crystallizes in an orthorhombic cell (a=17.6942(4) Å, b=34.1437(6) Å, c=10.0410(2) Å; space group Fdd2). Isolated nitridoborate anionic groups [BN{sub 2}]{sup 3–}, dumbbell-type Zintl polyanions [Si{sub 2}]{sup 2.8–}, and nitride anions N{sup 3–} are included in the structure. The structural formula is represented as (Ba{sup 2+}){sub 26}([BN{sub 2}]{sup 3–}){sub 12}[([Si{sub 2}]{sup 2.8–}){sub 1.25}(N{sup 3–}){sub 2×0.75}]{sub 2}. The [Si{sub 2}]{sup 2.8–} dumbbell with a Si–Si length of 2.177(5) Å has a bond order of 2.6, which is close to the triple bond of Si. - Graphical abstract: Single crystals of Ba{sub 26}B{sub 12}Si{sub 5}N{sub 27} grown by slow cooling from 900 °C have an orthorhombic crystal structure with space group Fdd2, containing nitridoborate anionic groups [BN{sub 2}]{sup 3–}, dumbbell-type Zintl polyanions [Si{sub 2}]{sup 2.8–}, and nitride anions N{sup 3–}. - Highlights: • A novel compound, Ba{sub 26}B{sub 12}Si{sub 5}N{sub 27}, was synthesized by slow cooling from 900 °C. • Single crystal X-ray diffraction clarified a new crystal structure. • Anionic groups [BN{sub 2}]{sup 3–} and dumbbell-type Zintl polyanions [Si{sub 2}]{sup 2.8–} are contained. • The [Si{sub 2}]{sup 2.8–} dumbbell has a bond order of 2.6, which is close to the triple bond.

  16. Semileptonic B{sub s} → D{sub s2}{sup *}(2573)l anti ν{sub l} transition in QCD

    Energy Technology Data Exchange (ETDEWEB)

    Azizi, K. [Dogus University, Department of Physics, Istanbul (Turkey); Sundu, H.; Sahin, S. [Kocaeli University, Department of Physics, Izmit (Turkey)

    2015-05-15

    We analyze the semileptonic B{sub s} → D{sub s2}{sup *}(2573)l anti ν{sub l} transition, where l = τ, μ or e, within the standard model.We apply the QCD sum rule approach to calculate the transition form factors entering the low energy Hamiltonian defining this channel. The fit functions of the form factors are used to estimate the total decay widths and branching fractions in all lepton channels. The orders of the branching ratios indicate that this transition is accessible at LHCb in the near future. (orig.)

  17. The crystal structure of Li{sub 2}B{sub 4}O{sub 7} compound in the temperature range 10-290 K

    Energy Technology Data Exchange (ETDEWEB)

    Adamiv, V.T. [Institute of Physical Optics, 23 Dragomanov Street, Lviv 79005 (Ukraine)], E-mail: adamiv@ifo.lviv.ua; Burak, Ya.V.; Teslyuk, I.M. [Institute of Physical Optics, 23 Dragomanov Street, Lviv 79005 (Ukraine)

    2009-05-05

    Structural investigation of Li{sub 2}B{sub 4}O{sub 7} in the 10-290 K temperature range has been carried out by means of high-resolution powder diffraction technique applying synchrotron radiation. The obtained results show high thermal stability of tetraborate groups in the 10-290 K temperature range. The planar BO{sub 3} triangles somewhat enlarge at heating, while the BO{sub 4} tetrahedra compress excessively at heating from 10 to 290 K. In the 10-290 K temperature range maximal changes were observed for structural parameters of Li atoms, while the parameters of O atoms show minimal temperature variations.

  18. Small angle neutron scattering studies of the flux line lattices in the borocarbide superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Eskildsen, Morten Ring

    1998-12-01

    This thesis describes small angle neutron scattering studies of the flux line lattice (FLL) in the following members of the borocarbide superconductors: YNi{sub 2}B{sub 2}C, ErNi{sub 2}B{sub 2}C, TmNi{sub 2}B{sub 2}C, LuNi{sub 2}B{sub 2}C, Y{sub 0.75}Lu{sub 0.25}Ni{sub 2}B{sub 2}C and Lu(Ni{sub 1-x}CO{sub x}){sub 2}B{sub 2}C with x = 1.5 - 9%. Of the materials ErN{sub 2}B{sub 2}C and TmNi{sub 2}B{sub 2}C exhibits coexisting superconductivity and magnetic ordering. Three main conclusions can be derived from the results in this thesis. Existence of a low field hexagonal to square symmetry transition of the FLL, ubiquitous to the superconducting borocarbides, magnetic and non-magnetic alike. This symmetry transition is due to the four-fold anisotropy of the Fermi surface, distorting the screening currents towards a square flow pattern. This four-fold anisotropy together with non-local electrodynamics induces a transition to a square FLL, as the field is increased. Changing the non-locality range shifts the square to hexagonal transition onset field. A static disordering of the FLL in YNi{sub 2}B{sub 2}C and LuNi{sub 2}B{sub 2}C. In these materials one observes a well ordered FLL, with a longitudinal correlation length exceeding 100 flux line spacings. As the applied field is increased the longitudinal correlation length, increases with field up to H/H{sub c2} {approx} 0.2. Above this field the FLL correlation length slowly starts to fall off, in contradiction to theoretical models. The existence of complex interactions between the magnetic state and the FLL in TmNi{sub 2}B{sub 2}C. This is signalled by coinciding changes in the FLL symmetry and in the magnetic structure. The FLL show a two-step symmetry transition from square to rhombic and then hexagonal with increased field. In addition, the FLL reflectivity shows distinct peaks as the thulium ions orders magnetically at T{sub N} and across the field driven magnetic transition. No explanation for this behaviour

  19. Damping and mechanical properties of (graphite+9Al{sub 2}O{sub 3}.2B{sub 2}O{sub 3})/Mg metal matrix composites

    Energy Technology Data Exchange (ETDEWEB)

    Choi, I.; Kim, D. [Dept. of Mechanical and Materials Engineering, Korea Maritime Univ., Pusan (Korea); Cho, K.; Park, I. [Dept. of Metallurgical Engineering, Pusan National Univ., Pusan (Korea)

    2004-07-01

    Mg alloys have potential to use automotive parts because of their weight and castability. High temperature strength and damping capacity is important to the automotive power train parts. Mg alloy has lower creep and thermal fatique strength but has better damping capacity than Al alloy. It is known that short fiber reinforced Mg metal matrix composites(MMC) exhibits superior high temperature strength and graphite reinforced Mg MMC shows excellent damping capacity. Therefore, in this study, the effect of graphite particles(15-25%) and alborex (9Al{sub 2}O{sub 3}.2B{sub 2}O{sub 3}) whiskers(5-15%) on the damping behavior and mechanical properties of Mg MMC was studied. Graphite particles and alborex whiskers were chosen to increase damping capacity and high temperature strength, respectively. The Mg MMC was fabricated by squeeze casting and the total quantity of reinforcements(graphite+alborex) was maintained to 30 volume percent. The damping capacity of the metal matrix composites was increased and the flexural strength and hardness were decreased with increasing the volume fraction of graphite particles, that is, reducing the volume fraction of alborex whiskers. (orig.)

  20. Epitaxial growth of YNi{sub 2}B{sub 2}C films on single crystal MgO substrates: an HRTEM investigation of the interface

    Energy Technology Data Exchange (ETDEWEB)

    Reibold, M.; Wimbush, S.C.; Holzapfel, B.; Kraemer, U

    2002-12-16

    Epitaxial thin films of the superconducting borocarbide compound YNi{sub 2}B{sub 2}C have been grown on single-crystal MgO (001) substrates using pulsed laser deposition. The deposition temperature has a strong influence on the structural properties of the films, which in turn affect the superconducting transition temperature, T{sub c}. The resulting phases and their orientations with respect to the substrate have been investigated by X-ray diffraction and HRTEM, using cross-section samples. For deposition temperatures around 750 deg. C, c-axis oriented growth of YNi{sub 2}B{sub 2}C films occurs preferentially. At lower temperatures a weaker a-axis orientation was found by X-ray diffraction, whereas by HRTEM grains with a-axis and a weak c-axis orientation could be identified. An interfacial layer some 100 nm thick was formed bordering on the substrate, comprising mainly Y{sub 2}O{sub 3} but also other epitaxially grown phases such as YNi{sub 4}B. The growth directions of Y{sub 2}O{sub 3} are [001] at 750 deg. C and [111] at lower temperatures. The in-plane orientations and the lattice mismatches of the bordering phases were also investigated.

  1. Revisiting B{sub s} → μ{sup +}μ{sup -} in the two-Higgs doublet models with Z{sub 2} symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Xiao-Dong [Central China Normal University, Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Wuhan, Hubei (China); Xinyang Normal University, College of Physics and Electronic Engineering, Xinyang, Henan (China); Yang, Ya-Dong [Central China Normal University, Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Wuhan, Hubei (China); Yuan, Xing-Bo [Yonsei University, Department of Physics and IPAP, Seoul (Korea, Republic of); Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Beijing (China)

    2016-03-15

    We revisit the rare leptonic decay B{sub s} → μ{sup +}μ{sup -} in the two-Higgs doublet models (2HDMs) with a softly broken Z{sub 2} symmetry, namely type-I, type-II, type-X and type-Y 2HDMs. We have derived the relevant full one-loop Wilson coefficients of the four 2HDMs from the recent calculation in the aligned 2HDM by Li, Lu and Pich, which could be mapped to all the four 2HDMs for both large and small tan β. It is found that a new term associated with the soft Z{sub 2} symmetry breaking parameter M can be enhanced by tan{sup 2} β in the type-II 2HDM, which has not been considered in the literature. Imposing both theoretical and experimental constraints, we have renewed the bounds on the parameter spaces of the four 2HDMs. Different from our previous paper, however, we find that all the four 2HDMs give sizable and similar contributions to B(B{sub s} → μ{sup +}μ{sup -}) within the stringently restricted parameter spaces, but very tiny as regards the mass-eigenstate rate asymmetry A{sub ΔΓ}; this makes it unfeasible to discriminate the four types of 2HDM with the correlations between the observables in B{sub s} → μ{sup +}μ{sup -} decay. (orig.)

  2. Preparation, heat treatment and photoluminescence properties of V-doped ZnO-SiO{sub 2}-B{sub 2}O{sub 3} glasses

    Energy Technology Data Exchange (ETDEWEB)

    Hamnabard, Zohreh, E-mail: zhamnabard@nrcam.org [Materials Research School, Ceramic Group, P.O. Box 14395-836, Alborz (Iran, Islamic Republic of); Khalkhali, Zahra, E-mail: khalkhali_z@yahoo.com [Department of Material Science, Ceramic Division, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Qazvini, Shamsi Sadat Alavi, E-mail: IRUH81@yahoo.com [Faculty of Materials Engineering, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Baghshahi, Saeid, E-mail: s.baghshahi@ikiu.ac.ir [Faculty of Engineering and Technology, I.K.I. University, Qazvin (Iran, Islamic Republic of); Maghsoudipour, Amir, E-mail: a_maghsoudi@merc.ac.ir [Ceramic Division, Materials and Energy Research Center, Alborz (Iran, Islamic Republic of)

    2012-05-15

    Four glasses in ZnO-SiO{sub 2}-B{sub 2}O{sub 3} ternary system were prepared by the melt quenching method with the objective of optimizing sub-nanosecond emission over the UV region of zinc borosilicate glasses used in superfast scintillators. The effect of vanadium addition and heat treatment on phase formation, microstructure and photoluminescence properties of the glasses was characterized by means of DTA, XRD, SEM and fluorescence spectrophotometer. Vanadium contributed to the near-band-edge emission in two ways, by introducing donor levels in the energy band of ZnO particles and by facilitating the precipitation of ZnO and willemite crystals. Furthermore, nucleation of willemite and zinc oxide phases, which are both the origins of the intense emission bands in the UV region, was facilitated with increasing either the time or temperature of heat treatments. Photoluminescence spectra showed the elimination of the visible emission band which is favorable in scintillating glasses. - Highlights: Black-Right-Pointing-Pointer Phase analysis, thermal behavior, microstructure and photoluminescence properties. Black-Right-Pointing-Pointer Crystallization driving forces and mechanisms. Black-Right-Pointing-Pointer Optical basicity of ZnO-SiO{sub 2}-B{sub 2}O{sub 3} glasses.

  3. Effect of irradiation temperature on crystallization of {alpha}-Fe induced by He irradiations in Fe{sub 80}B{sub 20} amorphous alloy

    Energy Technology Data Exchange (ETDEWEB)

    San-noo, Toshimasa; Toriyama, Tamotsu; Wakabayashi, Hidehiko; Iijima, Hiroshi [Musashi Inst. of Tech., Tokyo (Japan); Hayashi, Nobuyuki; Sakamoto, Isao

    1997-03-01

    Since amorphous alloys are generally highly resistant to irradiation and their critical radiation dose is an order of magnitude higher for Fe-B amorphous alloy than Mo-methods, these alloys are expected to become applicable as for fusion reactor materials. The authors investigated {alpha}-Fe crystallization in an amorphous alloy, Fe{sub 80}B{sub 20} using internal conversion electron Moessbauer spectroscopy. The amount of {alpha}-Fe component was found to increase by raising the He-irradiation dose. The target part was modified to enable He ion radiation at a lower temperature (below 400 K) by cooling with Peltier element. Fe{sub 80}B{sub 20} amorphous alloy was cooled to keep the temperature at 300 K and exposed to 40 keV He ion at 1-3 x 10{sup 8} ions/cm{sup 2}. The amount of {alpha}-Fe crystal in each sample was determined. The crystal formation was not observed for He ion radiation below 2 x 10{sup 18} ions/cm{sup 2}, but that at 3 x 10{sup 8} ions/ cm{sup 2} produced a new phase ({delta} +0.40 mm/sec, {Delta} = 0.89 mm/sec). The decrease in the radiation temperature from 430 to 300 K resulted to extremely repress the production of {alpha}-Fe crystal, suggesting that the crystallization induced by He-radiation cascade is highly depending on the radiation temperature. (M.N.)

  4. Growth and characterization of pure and Co{sup 2+}-doped Li{sub 2}B{sub 4}O{sub 7} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kaczmarek, S. [Szczecin University of Technology, Institute of Physics, Al. Piastow 48, Szczecin 70-310 (Poland); Berkowski, M. [Polish Academy of Sciences, Institute of Physics, al. Lotnikow 32/46, Warszawa 02-668 (Poland); Piwowarska, D.

    2007-12-15

    Pure and Co-doped Li{sub 2}B{sub 4}O{sub 7} (LBO) single crystals were grown by the Czochralski method. Starting concentrations of Co{sub 2}O{sub 3} in the melt were: 0.5, 0.85 and 1 mol% relative to Li{sub 2}CO{sub 3}. Technological factors affecting the quality of both crystals were discussed. Optical absorption and EPR spectra were analyzed to define the oxidation states and lattice sites of cobalt ions. It was shown that Co{sup 2+} ions enter LBO crystal at octahedral Li{sup +} site positions. Low-temperature EPR measurements revealed that two types of Co{sup 2+} complexes can be distinguished in the Li{sub 2}B{sub 4}O{sub 7}:Co crystals. Additional absorption calculated for {gamma}-irradiated crystals showed V{sub k} type defects suggesting the creation of cation vacancies during growth. The concentration of the defects decreases with an increase of intentional Co concentration. Introduction of cobalt ions to LBO crystal is limited probably by the formation of cobalt ion pairs or by the entrance of cobalt as Co{sup +}. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. In-situ Lorentz microscopy of Fe{sub 85}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 1} nanocrystalline soft magnetic alloys

    Energy Technology Data Exchange (ETDEWEB)

    Akase, Zentaro, E-mail: akase@tagen.tohoku.ac.jp [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198 (Japan); Aizawa, Shinji [Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198 (Japan); Shindo, Daisuke [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198 (Japan); Sharma, Parmanand [Research and Development Center for Ultra High Efficiency Nano-crystalline Soft Magnetic Materials, Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Makino, Akihiro [Research and Development Center for Ultra High Efficiency Nano-crystalline Soft Magnetic Materials, Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2015-02-01

    Microstructure dependence of magnetic properties of soft magnetic Fe–Si–B–P–Cu nanocrystalline alloys were studied by using in-situ Lorentz microscopy in a transmission electron microscope equipped with a magnetizing system. In particular, we investigated in detail motion of magnetic domain walls in heat-treated Fe{sub 85}Si{sub 12}B{sub 6}P{sub 4}Cu{sub 1} amorphous ribbons. Smooth motion of domain walls was observed for the optimally heat-treated (at 430 °C) nano-crystalline alloy. Pinning of domain walls was observed for higher-temperature-heat-treated (470 °C) ribbons. Both ribbons showed a nanocrystalline structure containing α-Fe crystallites of about 15 nm in size. Electron diffraction patterns indicated that the higher-temperature-heat-treated samples contained boride precipitates, which is considered to cause less smooth domain wall motion. - Highlights: • Magnetic properties of newly developed Fe–Si–B–P–Cu nanocrystalline alloys are analyzed by TEM. • Motion of magnetic domain walls were visualized by in-situ Lorentz microscopy. • Borides (Fe{sub 2}B) in heat-treated specimen cause reduction in domain wall motion smoothness.

  6. Magnetic properties and amorphous-to-nanocrystalline transformation by thermal treatments in Fe{sub 84.3}Si{sub 4}P{sub 3}B{sub 8}Cu{sub 0.7} amorphous thin films

    Energy Technology Data Exchange (ETDEWEB)

    Coïsson, Marco, E-mail: m.coisson@inrim.it [INRIM, Electromagnetics Division, strada delle Cacce 91, 10135 Torino (Italy); Viteri Villacis, Patricio J. [Università degli Studi di Torino, Chemistry Department, via P. Giuria 7, 10125 Torino (Italy); Barrera, Gabriele [INRIM, Electromagnetics Division, strada delle Cacce 91, 10135 Torino (Italy); Università degli Studi di Torino, Chemistry Department, via P. Giuria 7, 10125 Torino (Italy); Celegato, Federica; Enrico, Emauele [INRIM, Electromagnetics Division, strada delle Cacce 91, 10135 Torino (Italy); Rizzi, Paola [Università degli Studi di Torino, Chemistry Department, via P. Giuria 7, 10125 Torino (Italy); Tiberto, Paola; Vinai, Franco [INRIM, Electromagnetics Division, strada delle Cacce 91, 10135 Torino (Italy); Fiore, Gianluca; Battezzati, Livio [Università degli Studi di Torino, Chemistry Department, via P. Giuria 7, 10125 Torino (Italy)

    2014-12-05

    Highlights: • High-BS alloy, prepared in thin films form. • As-prepared films display low coercivity, comparable to rapidly quenched ribbons. • Furnace annealed films show even lower coercivity while retaining a high saturation. • On annealing, a fully nanocrystalline state is achieved in thin films. - Abstract: Thin films of nominal composition Fe{sub 84.3}Si{sub 4}P{sub 3}B{sub 8}Cu{sub 0.7} have been prepared by sputtering from ribbons of the same alloy. Their microstructure has been studied by means of X-ray diffraction, differential scanning calorimetry and transmission electron microscopy, and reveals a partly amorphous state in the as-prepared samples. Their magnetic properties are soft and comparable to those measured on rapidly quenched ribbons. After annealing in furnace at temperatures up to 400 °C, their soft magnetic properties are improved thanks to the development of a fully nanocrystalline state. Annealing at higher temperature causes the coarsening of the α-Fe like grains, the development of hard magnetic phases and an increase of the coercive field.

  7. The effect of furnace annealing and surface crystallization on the anisotropy, {delta}E and magnetoimpedance effects in Fe{sub 71}Cr{sub 7}Si{sub 9}B{sub 13} amorphous wires

    Energy Technology Data Exchange (ETDEWEB)

    Bayri, N; Kolat, V S; Atalay, F E; Atalay, S [Physics Department, Science and Arts Faculty, Inonu University, 44069 Malatya (Turkey)

    2004-11-21

    The dependence of the magnetization loops, coercivity, anisotropy constant, {delta}E and magnetoimpedance (MI) effects in positively magnetostrictive Fe{sub 71}Cr{sub 7}Si{sub 9}B{sub 13} amorphous wires on annealing conditions were studied. Samples were annealed at temperatures of 440 deg. C and 460 deg. C for durations between 0.3 and 300 min. The results indicate that progressive annealing first leads to relief of internal stresses and annealing of wires at 460 deg. C for 60 min produces the minimum coercivity of about 1 A m{sup -1}. Further annealing increases the coercivity and anisotropy, due to partial crystallization at the surface. It was found that the anisotropy changes its direction to the circumferential direction with the surface crystallization. The maximum change in Young's modulus was measured to be about 75% in a partly surface crystalline sample. It was observed that the magnitude of the MI effect of the stress relieved sample could exceed 200% at 1 MHz.

  8. Crystal structures and compressibility of novel iron borides Fe{sub 2}B{sub 7} and Fe{sub x}B{sub 50} synthesized at high pressure and high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Bykova, E., E-mail: elena.bykova@uni-bayreuth.de [Bavarian Research Institute of Experimental Geochemistry and Geophysics, University of Bayreuth, D-95440 Bayreuth (Germany); Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth (Germany); Gou, H.; Bykov, M. [Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth (Germany); Hanfland, M. [European Synchrotron Radiation Facility, BP 220, Grenoble F-38043 (France); Dubrovinsky, L. [Bavarian Research Institute of Experimental Geochemistry and Geophysics, University of Bayreuth, D-95440 Bayreuth (Germany); Dubrovinskaia, N. [Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth (Germany)

    2015-10-15

    We present here a detailed description of the crystal structures of novel iron borides, Fe{sub 2}B{sub 7} and Fe{sub x}B{sub 50} with various iron content (x=1.01(1), 1.04(1), 1.32(1)), synthesized at high pressures and high temperatures. As revealed by high-pressure single-crystal X-ray diffraction, the structure of Fe{sub 2}B{sub 7} possesses short incompressible B–B bonds, which make it as stiff as diamond in one crystallographic direction. The volume compressibility of Fe{sub 2}B{sub 7} (the bulk modulus K{sub 0}= 259(1.8) GPa, K{sub 0}′= 4 (fixed)) is even lower than that of FeB{sub 4} and comparable with that of MnB{sub 4}, known for high bulk moduli among 3d metal borides. Fe{sub x}B{sub 50} adopts the structure of the tetragonal δ-B, in which Fe atoms occupy an interstitial position. Fe{sub x}B{sub 50} does not show considerable anisotropy in the elastic behavior. - Graphical abstract: Crystal structures of novel iron borides, Fe{sub 2}B{sub 7} and Fe{sub x}B{sub 50} (x=1.01(1), 1.04(1), 1.32(1)). - Highlights: • Novel iron borides, Fe{sub 2}B{sub 7} and Fe{sub x}B{sub 50}, were synthesized under HPHT conditions. • Fe{sub 2}B{sub 7} has a unique orthorhombic structure (space group Pbam). • Fe{sub 2}B{sub 7} possesses short incompressible B–B bonds that results in high bulk modulus. • Fe{sub x}B{sub 50} adopts the structure of the tetragonal δ-B composed of B{sub 12} icosahedra. • In Fe{sub x}B{sub 50} intraicosahedral bonds are stiffer than intericosahedral ones.

  9. Crystal electric field splitting of R{sup 3+}-ions in pure and Co- and Cu-doped RNi{sub 2}B{sub 2}C (R=Ho, Er, Tm)

    Energy Technology Data Exchange (ETDEWEB)

    Gasser, U.; Allenspach, P.; Henggeler, W.; Zolliker, M.; Furrer, A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    From the crystal-electric-field (CEF) splitting of the R{sup 3+}-ions, the CEF parameters of RNi{sub 2}B{sub 2}C (R=Ho, Er, Tm) were deduced. In order to get information about the influence of the variation of the density of states (DOS) at the Fermi level (E{sub F}), CEF spectroscopy measurements with Co- and Cu-doped ErNi{sub 2}B{sub 2}C-samples were performed. (author) 1 fig., 1 tab., 1 ref.

  10. Measurement of the effective B{sub s}{sup 0}→J/ψK{sub S}{sup 0} lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [Fakultät Physik, Technische Universität Dortmund, Dortmund (Germany); Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amerio, S. [Sezione INFN di Padova, Padova (Italy); Amhis, Y. [LAL, Université Paris-Sud, CNRS/IN2P3, Orsay (France); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universität Zürich, Zürich (Switzerland); Andreassen, R. [University of Cincinnati, Cincinnati, OH (United States); and others

    2013-08-11

    This paper reports the first measurement of the effective B{sub s}{sup 0}→J/ψK{sub S}{sup 0} lifetime and an updated measurement of its time-integrated branching fraction. Both measurements are performed with a data sample, corresponding to an integrated luminosity of 1.0 fb{sup −1} of pp collisions, recorded by the LHCb experiment in 2011 at a centre-of-mass energy of 7 TeV. The results are: τ{sub J/ψK{sub S{sup 0eff}}}=1.75±0.12(stat)±0.07(syst) ps and B(B{sub s}{sup 0}→J/ψK{sub S}{sup 0})=(1.97±0.23)×10{sup −5}. For the latter measurement, the uncertainty includes both statistical and systematic sources.

  11. Measurement of the B{sub s}{sup 0}{yields}J/{psi}K{sub S}{sup 0} branching fraction

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); Archilli, F. [Laboratori Nazionali dell' INFN di Frascati, Frascati (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); and others

    2012-07-09

    The B{sub s}{sup 0}{yields}J/{psi}K{sub S}{sup 0} branching fraction is measured in a data sample corresponding to 0.41 fb{sup -1} of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to the penguin contributions affecting the sin2{beta} measurement from B{sup 0}{yields}J/{psi}K{sub S}{sup 0}. The time-integrated branching fraction is measured to be B(B{sub s}{sup 0}{yields}J/{psi}K{sub S}{sup 0})=(1.83{+-}0.28) Multiplication-Sign 10{sup -5}. This is the most precise measurement to date.

  12. B{sub c}B{sub c}J/ψ vertex form factor at finite temperature in the framework of QCD sum rules approach

    Energy Technology Data Exchange (ETDEWEB)

    Yazici, E.; Sundu, H.; Veliev, E.V. [Kocaeli University, Department of Physics, Izmit (Turkey)

    2016-02-15

    The strong form factor of the B{sub c}B{sub c}J/ψ vertex is calculated in the framework of the QCD sum rules method at finite temperature. Taking into account additional operators appearing at finite temperature, a thermal Wilson expansion is obtained and QCD sum rules are derived. While increasing the temperature, the strong form factor remains unchanged up to T ≅ 100 MeV but slightly increases after this point. After T ≅ 160 MeV, the form factor suddenly decreases up to T ≅ 170 MeV. The obtained result of the coupling constant by fitting the form factor at Q{sub 2} = -m{sup 2}{sub offshell} at T = 0 is in a very good agreement with the QCD sum rules calculations in the case of vacuum. Our prediction can be checked in future experiments. (orig.)

  13. Defects spectroscopy by means of the simple trapping model of the Fe{sub 78}Si{sub 9}B{sub 13} alloy; Espectroscopia de defectos mediante el modelo de atrapamiento simple de la aleacion Fe{sub 78}Si{sub 9}B{sub 13}

    Energy Technology Data Exchange (ETDEWEB)

    Lopez M, A.; Cabral P, A.; Garcia S, S.F. [Laboratorio de Fisica Avanzada, Facultad de Ciencias, Universidad Autonoma del Estado de Mexico. El Cerillo Piedras Blancas, 50000 Toluca, Estado de Mexico (Mexico)

    2007-07-01

    In this work it is analyzed quantitatively the results of the positron annihilation in the Fe{sub 78}Si{sub 9}B{sub 13} alloy by means of the simple trapping model. From this analysis its are derived: a reason of positron trapping in the defects (K), the defects concentration (C{sub d}) and the electronic density associated to the defect (n{sub d}); both first parameters, (K, C{sub d}) its increase and n{sub d} diminishes when increasing the alloy temperature. From this analysis it is also inferred that the defect consists of a multi vacancy of between 15 and 20 mono vacancies. (Author)

  14. Conical intersections between X{sup 2}A{sub 1} and A{sup 2}B{sub 2} electronic states of NO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Sardar, Subhankar; Mukherjee, Saikat; Paul, Amit Kumar [Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India); Adhikari, Satrajit, E-mail: pcsa@iacs.res.in [Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India)

    2013-04-18

    Highlights: ► Global ab initio potential surfaces (PES) of X{sup 2}A{sub 1} and A{sup 2}B{sub 2} states of NO{sub 2} are computed. ► Non Adiabatic Coupling Terms (NACTs) between those states are also calculated. ► Our Beyond BO theory confirms those PESs consist general SAA CIs and RT interaction. ► Singularities of NACT on normal mode coordinates indicate the presence of CI. ► Calculated Adiabatic to Diabatic Transformation matrix show sign change for CI. - Abstract: We explore both the general symmetry-allowed accidental (SAA) conical intersections (CIs) and Renner–Teller (RT) interactions prevailed between the ground (X{sup 2}A{sub 1}) and first excited (A{sup 2}B{sub 2}) electronic states of NO{sub 2} in the configuration space of normal mode coordinates. Global ab initio potential-energy surfaces and Non Adiabatic Coupling Term (NACT) between those states are reported. For each of the three pairs of normal mode (Q{sub 1},Q{sub 2},Q{sub 3}), calculated NACT show singularity at different positions, which are used to calculate Adiabatic-to-Diabatic Transformation (ADT) angles and thereby, the diagonal elements of ADT matrix display (i) sign change for odd number of SAA CI (s) and (ii) no sign change for even number of SAA CIs as well as Renner–Teller interactions. Similar to Jahn–Teller CI, the existence of SAA CIs are, further, confirmed by Longuet-Higgins’ phase change.

  15. Corrosion behavior of Nd{sub 9.4}Pr{sub 0.6}Fe{sub bal.}Co{sub 6}B{sub 6}Ga{sub 0.5}Ti{sub x}C{sub x} (x=0, 1.5, 3, 6) nanocomposites annealed melt-spun ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Nezakat, M. [School of Metallurgy and Materials Engineering, Faculty of Engineering, University of Tehran, Tehran 11155-4563 (Iran, Islamic Republic of); Gholamipour, R. [Iranian Research Organization for Science and Technology (IROST), Tehran 15815-3538 (Iran, Islamic Republic of)], E-mail: rgholamipour@gmail.com; Amadeh, A.; Mohammadi, A. [School of Metallurgy and Materials Engineering, Faculty of Engineering, University of Tehran, Tehran 11155-4563 (Iran, Islamic Republic of); Ohkubo, T. [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan)

    2009-10-15

    The effect of Ti and C additions on the corrosion behavior of Nd{sub 9.4}Pr{sub 0.6}Fe{sub bal.}Co{sub 6}B{sub 6}Ga{sub 0.5}Ti{sub x}C{sub x} (x=0, 1.5, 3, 6) isotropic nanocomposite melt-spun ribbons in 3.5 wt% sodium chloride solution was studied. The melt-spun ribbons were annealed at 750 {sup o}C for 10 min in argon-filled quartz capsules. The microstructure of multiphase nanocrystalline samples and corrosion products was characterized using the X-ray diffraction and electron microscopy techniques. The electrochemical behavior was assessed using potentiodynamic polarization and electrochemical impedance spectroscopy. The results show that the addition of Ti and C increases the corrosion resistance of NdFeB ribbons; the best corrosion resistance was obtained for 1.5 wt% Ti and C content.

  16. Effect of Co on the microstructure, magnetic properties and thermal stability of bulk Fe{sub 73-x}Co{sub x}Nb{sub 5}Y{sub 3}B{sub 19} (where x = 0 or 10) amorphous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Nabialek, Marcin G., E-mail: nmarcell@wp.pl [Institute of Physics, Czestochowa University of Technology, 19 Armii Krajowej Av., 42-200 Czestochowa (Poland); Szota, Michal [Institute of Materials Engineering, Czestochowa University of Technology, 19 Armii Krajowej Av., 42-200 Czestochowa (Poland); Dospial, Marcin J. [Institute of Physics, Czestochowa University of Technology, 19 Armii Krajowej Av., 42-200 Czestochowa (Poland)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer The paper presents the results of structure, thermal stability and magnetic properties of Fe{sub 73-x}Co{sub x}Nb{sub 5}Y{sub 3}B{sub 19} (where x = 0 or 10) bulk amorphous alloys in the as-cast state in the form of plates with a thickness of 0.5 mm and an area of 100 mm{sup 2}. Black-Right-Pointing-Pointer Results of this study indicate that despite the negative effect of exchange of Fe onto Co, what results in decrease of the saturation of magnetization, Curie temperature and thermal stability, it is clear that such a slight deterioration of these parameters is compensated with a significant reduction of the coercivity field values. Black-Right-Pointing-Pointer What testify that amorphous alloys with the addition of Co can be successfully used as magnetic cores in modern medium power transformers. - Abstract: The paper presents the results of structure, thermal stability and magnetic properties of bulk Fe{sub 73-x}Co{sub x}Nb{sub 5}Y{sub 3}B{sub 19} (where x = 0 or 10) amorphous alloys in the as-cast state, in the form of 0.5 mm thick plates with an area of 100 mm{sup 2}. The amorphous structure of the investigated alloys was confirmed by studies of Moessbauer effect and X-ray diffractometry. On the basis of measurements performed using a vibrating sample magnetometer (VSM), it was found that substituting 10% of Fe with Co in Fe{sub 73-x}Co{sub x}Nb{sub 5}Y{sub 3}B{sub 19} alloy, had only a small effect on the value of saturation magnetization ({mu}{sub 0}M{sub S}), and was of the same importance in terms of the values of the coercivity field (H{sub C}) and the Curie temperature (T{sub C}). The magnetization for both samples increases in high magnetic fields due to rotation of magnetic moments near the structural defects called quasidislocalised dipoles, near the area known as the approach to ferromagnetic saturation. For field values with a linear relationship ({mu}{sub 0}H){sup -1} of the reduced saturation magnetization

  17. Study of CP violation in Bx to J/psi phi decays at DZero

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Derek A.; /Northwestern U.

    2008-12-01

    In a universe dominated by matter, the source of CP violation may explain one of the greatest mysteries in particle physics: what happened to the antimatter? The Standard Model successfully describes CP violation in the B{sup +} and B{sub d}{sup 0} systems, yet insufficiently accounts for the observed matter-antimatter asymmetry. The Standard Model predicts a small value of CP violation in the B{sub s}{sup 0} meson system, which has only recently been experimentally tested. A measurement of large, anomalous CP violation in the B{sub s}{sup 0} system would be a clear indication of new physics sources beyond the Standard Model. This dissertation describes a study of CP violation in approximately 2000 B{sub s}{sup 0} {yields} J/{psi}{phi} decays reconstructed in a 2.8 fb{sup -1} data sample collected by the D0 Run II detector at Fermi National Accelerator Laboratory in Batavia, Illinois. This data was provided by p{bar p} collisions at {radical}s = 1.96 TeV delivered by the Tevatron accelerator between April 2002 and August 2007. Flavor-tagged B{sub s}{sup 0} {yields} J/{psi}({mu}{sup +}{mu}{sup -}){phi}(K{sup +}K{sup -}) decays and an angular analysis are used to study the time evolution of the final state angular distributions. From this analysis, we measure the width difference between the heavy and light mass eigenstates, B{sub s}{sup L} and B{sub s}{sup H}, to be {Delta}{Lambda}{sub s} = 0.19 {+-} 0.07 and the CP-violating phase {phi}{sub s} = -0.57{sub -0.30}{sup +0.24}.

  18. Phase transformations of Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 15.5}B{sub 7} amorphous alloy upon thermal treatment

    Energy Technology Data Exchange (ETDEWEB)

    Gavrilovic, Aleksandra [CEST Centre of Electrochemical Surface Technology, A-2700 Wiener Neustadt (Austria); Minic, Dusan M. [Technical Faculty of Cacak, University of Kragujevac, 32000 Cacak (Serbia); Rafailovic, Lidija D. [CEST Centre of Electrochemical Surface Technology, A-2700 Wiener Neustadt (Austria); Physics of Nanostructured Materials, Faculty of Physics, University of Vienna, A-1090 Vienna (Austria); Angerer, Paul; Wosik, Jaroslaw [CEST Centre of Electrochemical Surface Technology, A-2700 Wiener Neustadt (Austria); Maricic, Aleksa [Technical Faculty of Cacak, University of Kragujevac, 32000 Cacak (Serbia); Minic, Dragica M., E-mail: dminic@ffh.bg.ac.r [Faculty of Physical Chemistry, University of Belgrade, 11001 Belgrade (Serbia)

    2010-08-20

    The structural transformations of Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 15.5}B{sub 7} amorphous alloy under non-isothermal as well as isothermal conditions were studied. Differential scanning calorimetry (DSC) showed that slow heating rates induce a series of stepwise structural transformations consisting of endothermic peaks and more pronounced exothermic peaks in the broad temperature range from 350 to 970 K. Over this range the system changed from an as-deposited amorphous alloy of higher excess free energy to an annealed sample exhibiting lower excess of free energy. X-ray diffraction (XRD) analysis found that primary crystallization started with formation of a face-centred Fe{sub 3}Si phase in an amorphous matrix. At higher temperatures (between 780 and 920 K) we detected, in addition to the Fe{sub 3}Si phase, which reached an almost constant value of 85 wt%, three new phases, FeCu{sub 4}, Fe{sub 16}Nb{sub 6}Si{sub 7} and Fe{sub 2}B. Further annealing above 923 K led to, with Si initially migrating from the Fe-Si phase to the Nb-rich grain boundaries, formation of two new phases, Fe{sub 5}Si{sub 3} and Nb{sub 5}Si{sub 3}. The Fe content in the cubic Fe-Si phase was estimated by means of a change in lattice parameter. Below 923 K the size of crystallites for the major Fe{sub 3}Si phase was less than 10 nm. It was shown that further heating induced rapid crystallite growth, reaching a size greater than 500 nm at 1123 K.

  19. The substitution effect of chromium on the magnetic properties of (Fe{sub 1−x}Cr{sub x}){sub 80}Si{sub 6}B{sub 14} metallic glasses (0.02≤x≤0.14)

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez-Alonso, Pablo [Departamento de Electricidad y Electrónica, Universidad del País Vasco, Barrio Sarriena s/n, 48940 Leioa (Spain); Santos, J.D.; Pérez, María J. [Departamento de Física, Universidad de Oviedo, c/ Calvo Sotelo s/n, 33007 Oviedo (Spain); Sánchez-Valdes, C.F.; Sánchez Llamazares, J.L. [División de Materiales Avanzados, Instituto Potosino de Investigación Científica y Tecnológica A.C., Camino a la presa San José 2055, CP 78216 San Luis Potosí (Mexico); Gorria, Pedro, E-mail: pgorria@uniovi.es [Departamento de Física, EPI, Universidad de Oviedo, 33203 Gijón (Spain)

    2013-12-15

    Magnetization studies were carried out to characterize the magnetic properties of the Iron-rich metallic glasses (Fe{sub 1−x}Cr{sub x}){sub 80}Si{sub 6}B{sub 14} with 0.02≤x≤0.14. The Curie temperature T{sub C} diminishes almost linearly with the increase in the Cr-content from 401 K (x=0.10) to 291 K (x=0.14), while the saturation magnetization M{sub S} at T=5 K also undergoes a linear reduction from 169 Am{sup 2} kg{sup −1} (x=0.02) to 87 Am{sup 2} kg{sup −1} (x=0.14). These results suggest that the system should become paramagnetic for x≈0.22. The magneto-caloric properties of samples with T{sub C} near room temperature, i.e., with x=0.12 and 0.14, were investigated up to a maximum magnetic field change of 8 T. Both ribbons are characterized by a very broad temperature dependence of the magnetic entropy change ΔS{sub M}(T) and moderate peak values of 2.9 Jkg{sup −1} K{sup −1} and 2.6 Jkg{sup −1} K{sup −1}, respectively. - Highlights: • We report on the magnetic properties of (Fe{sub 1−x}Cr{sub x}){sub 80}Si{sub 6}B{sub 14} metallic glasses with 0.02≤x≤0.14. • Curie temperature and saturation magnetization values reduce linearly as the chromium content increases. • The magneto-caloric response up to 8 T has been measured for samples with x=0.12 and 0.14.

  20. Up-regulation of nucleotide excision repair in mouse lung and liver following chronic exposure to aflatoxin B{sub 1} and its dependence on p53 genotype

    Energy Technology Data Exchange (ETDEWEB)

    Mulder, Jeanne E. [Pharmacology and Toxicology Graduate Program, Department of Biomedical and Molecular Sciences, Queen' s University Kingston, Ontario K7L 3N6 (Canada); Bondy, Genevieve S.; Mehta, Rekha [Toxicology Research Division, 2202D, Bureau of Chemical Safety, Food Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario K1A 0K9 (Canada); Massey, Thomas E., E-mail: masseyt@queensu.ca [Pharmacology and Toxicology Graduate Program, Department of Biomedical and Molecular Sciences, Queen' s University Kingston, Ontario K7L 3N6 (Canada)

    2014-03-01

    Aflatoxin B{sub 1} (AFB{sub 1}) is biotransformed in vivo into an epoxide metabolite that forms DNA adducts that may induce cancer if not repaired. p53 is a tumor suppressor gene implicated in the regulation of global nucleotide excision repair (NER). Male heterozygous p53 knockout (B6.129-Trp53{sup tm1Brd}N5, Taconic) and wild-type mice were exposed to 0, 0.2 or 1.0 ppm AFB{sub 1} for 26 weeks. NER activity was assessed with an in vitro assay, using AFB{sub 1}-epoxide adducted plasmid DNA as a substrate. For wild-type mice, repair of AFB{sub 1}–N7-Gua adducts was 124% and 96% greater in lung extracts from mice exposed to 0.2 ppm and 1.0 ppm AFB{sub 1} respectively, and 224% greater in liver extracts from mice exposed to 0.2 ppm AFB{sub 1} (p < 0.05). In heterozygous p53 knockout mice, repair of AFB{sub 1}–N7-Gua was only 45% greater in lung extracts from mice exposed to 0.2 ppm AFB{sub 1} (p < 0.05), and no effect was observed in lung extracts from mice treated with 1.0 ppm AFB{sub 1} or in liver extracts from mice treated with either AFB{sub 1} concentration. p53 genotype did not affect basal levels of repair. AFB{sub 1} exposure did not alter repair of AFB{sub 1}-derived formamidopyrimidine adducts in lung or liver extracts of either mouse genotype nor did it affect XPA or XPB protein levels. In summary, chronic exposure to AFB{sub 1} increased NER activity in wild-type mice, and this response was diminished in heterozygous p53 knockout mice, indicating that loss of one allele of p53 limits the ability of NER to be up-regulated in response to DNA damage. - Highlights: • Mice are chronically exposed to low doses of the mycotoxin aflatoxin B{sub 1} (AFB{sub 1}). • The effects of AFB{sub 1} and p53 status on nucleotide excision repair are investigated. • AFB{sub 1} increases nucleotide excision repair in wild type mouse lung and liver. • This increase is attenuated in p53 heterozygous mouse lung and liver. • Results portray the role of p53 in

  1. Measurements of the B{sup +}, B{sup 0}, B{sub s}{sup 0} meson and Λ{sub b}{sup 0} baryon lifetimes

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Collaboration: The LHCb Collaboration; and others

    2014-04-16

    Measurements of b-hadron lifetimes are reported using pp collision data, corresponding to an integrated luminosity of 1.0 fb{sup −1}, collected by the LHCb detector at a centre-of-mass energy of 7 TeV. Using the exclusive decays B{sup +}→J/ψK{sup +}, B{sup 0}→J/ψK{sup ∗}(892){sup 0}, B{sup 0}→J/ψK{sub s}{sup 0}, Λ{sub b}{sup 0}→J/ψΛ and B{sub s}{sup 0}→J/ψϕ the average decay times in these modes are measured to be τ{sub B{sup +}→J/ψK{sup +}} =1.637±0.004±0.003 ps, τ{sub B{sup 0}→J/ψK{sup ∗}{sup 0}} =1.524±0.006±0.004 ps, τ{sub B{sup 0}→J/ψK{sub s{sup 0}}} =1.499±0.013±0.005 ps, τ{sub Λ{sub b{sup 0}→J/ψΛ}} =1.415±0.027±0.006 ps, τ{sub B{sub s{sup 0}→J/ψϕ}} =1.480±0.011±0.005 ps, where the first uncertainty is statistical and the second is systematic. These represent the most precise lifetime measurements in these decay modes. In addition, ratios of these lifetimes, and the ratio of the decay-width difference, ΔΓ{sub d}, to the average width, Γ{sub d}, in the B{sup 0} system, ΔΓ{sub d}/Γ{sub d}=−0.044±0.025±0.011, are reported. All quantities are found to be consistent with Standard Model expectations.

  2. Table-like magnetocaloric effect of Fe{sub 88−x}Nd{sub x}Cr{sub 8}B{sub 4} composite materials

    Energy Technology Data Exchange (ETDEWEB)

    Lai, J.W.; Zheng, Z.G.; Zhong, X.C. [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Franco, V. [Departamento Física de la Materia Condensada, ICMSE-CSIC, Universidad de Sevilla, P.O. Box 1065, 41080 Sevilla (Spain); Montemayor, R.; Liu, Z.W. [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Zeng, D.C., E-mail: medczeng@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China)

    2015-09-15

    The narrow working temperature range due to the sharp magnetic entropy change |ΔS{sub M}| peak and large thermal or magnetic hysteresis restricts the practical application of magnetocaloric materials. In this work, the table-like magnetocaloric effect (MCE) was obtained in the multilayer composite of Fe{sub 88−x}Nd{sub x}Cr{sub 8}B{sub 4} alloys with various Nd substitutions for Fe (x=5, 8, 10, 12, and 15), which were prepared by arc-melting followed by melt-spinning. The substation of Nd was found to enhance the glass-forming ability. For the alloys with Nd substitution from 5 at% to 15 at%, the Curie temperature (T{sub C}) ranged from 322 K to 350 K and the peak value of |ΔS{sub M}| remained almost constant, 3.4–3.5 J/(kg K) under an applied field of 0–5 T. The composite with various Nd contents was prepared by stocking the ribbons layer by layer. The |ΔS{sub M}| of the composite approached a nearly constant value of ∼3.2 J/(kg K) in a field change of 0–5 T in a wide temperature span over 40 K, resulting in large refrigerant capacity value of >408 J/kg. This |ΔS{sub M}| value was much larger than the previous reported Fe-based amorphous composite Fe{sub 78−x}Ce{sub x}Si{sub 4}Nb{sub 5}B{sub 12}Cu{sub 1}. This composite can be used as the working material in the Ericsson-cycle magnetic regenerative refrigerator around room temperature. - Highlights: • The T{sub C} ranges from 322 K to 350 K when increasing Nd substitution from 5 to 15 at%. • |ΔS{sub M}| remains relatively constant, about 3.4–3.5 J/(kg K) under H=0–5 T. • RC decreases from 93 to 78 J/kg in a field change of 1.5 T when Nd increasing. • Table-like MCE ,|ΔS{sub M}| ~3.2J/kg K under 0–5 T, appeared in the composite. • A wide working temperature range (40 K) and enhanced RC (>408J/kg) were obtained in the composite.

  3. EPR identification of defects responsible for thermoluminescence in Cu-doped lithium tetraborate (Li{sub 2}B{sub 4}O{sub 7}) crystals

    Energy Technology Data Exchange (ETDEWEB)

    Brant, A.T., E-mail: Adam.Brant.ctr@afit.edu [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, OH 45433 (United States); Buchanan, D.A.; McClory, J.W. [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, OH 45433 (United States); Dowben, P.A. [Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588 (United States); Adamiv, V.T.; Burak, Ya.V. [Institute of Physical Optics, 23 Dragomanov St., Lviv 79005 (Ukraine); Halliburton, L.E. [Department of Physics, West Virginia University, Morgantown, WV 26505 (United States)

    2013-07-15

    Electron paramagnetic resonance (EPR) is used to identify the electron and hole traps responsible for thermoluminescence (TL) peaks occurring near 100 and 200 °C in copper-doped lithium tetraborate (Li{sub 2}B{sub 4}O{sub 7}) crystals. As-grown crystals have Cu{sup +} and Cu{sup 2+} ions substituting for lithium and have Cu{sup +} ions at interstitial sites. All of the substitutional Cu{sup 2+} ions in the as-grown crystals have an adjacent lithium vacancy and give rise to a distinct EPR spectrum. Exposure to ionizing radiation at room temperature produces a second and different Cu{sup 2+} EPR spectrum when a hole is trapped by substitutional Cu{sup +} ions that have no nearby defects. These two Cu{sup 2+} trapped-hole centers are referred to as Cu{sup 2+}-V{sub Li} and Cu{sub active}{sup 2+}, respectively. Also during the irradiation, two trapped-electron centers in the form of interstitial Cu{sup 0} atoms are produced when interstitial Cu{sup +} ions trap electrons. They are observed with EPR and are labeled Cu{sub A}{sup 0} and Cu{sub B}{sup 0}. When an irradiated crystal is warmed from 25 to 150 °C, the Cu{sub active}{sup 2+} centers have a partial decay step that correlates with the TL peak near 100 °C. The concentrations of Cu{sub A}{sup 0} and Cu{sub B}{sup 0} centers, however, increase as the crystal is heated through this range. As the crystal is further warmed between 150 and 250 °C, the EPR signals from the Cu{sub active}{sup 2+} hole centers and Cu{sub A}{sup 0} and Cu{sub B}{sup 0} electron centers decay simultaneously. This decay step correlates with the intense TL peak near 200 °C. -- Highlights: ► We use EPR to identify a Cu{sup 2+} center and two Cu{sup 0} defects in Cu-doped Li{sub 2}B{sub 4}O{sub 7}. ► These defects form when our crystal is irradiated with X-rays at room temperature. ► We also observe two above-room-temperature thermoluminescence (TL) peaks. ► A pulsed anneal experiment correlates the decay of the EPR signals to two

  4. Soft magnetic properties and thermal stability of bulk Fe{sub 83}B{sub 17} alloy prepared by undercooling and Cu-mold casting methods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Changlin, E-mail: ycl@nwpu.edu.cn; Zhang, Jun; Huang, Huili; Sheng, Gang; Liu, Feng

    2015-06-15

    The thermal stability and soft magnetic properties of bulk Fe{sub 83}B{sub 17} rods with nano-lamellar eutectic structures and metastable Fe{sub 3}B phases were investigated by annealing at 973–1273 K for 1.5 h. Samples with a diameter of 3 mm were prepared by undercooling solidification combined with Cu-mold casting. The decomposition of Fe{sub 3}B and the transformation of nano-lamellar eutectic structures were finished after annealing at 1173 K for 1.5 h. Increasing annealing temperature showed that the soft magnetic properties of the sample were kept relatively stable. The saturation magnetization and retentivity were decreased only slightly, while the coercivity was decreased significantly. - Highlights: • Thermal stability of the nano-lamellar eutectic structure was obtained. • Thermal stability of the metastable Fe{sub 3}B phase was obtained. • The soft magnetic properties of the sample remain stability by annealing. • Nano-lamellar eutectic structures enhance the soft magnetic properties.

  5. Preparation of a bulk Fe{sub 83}B{sub 17} soft magnetic alloy by undercooling and copper-mold casting methods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Changlin, E-mail: ycl@nwpu.edu.cn; Sheng, Gang; Chen, Guiyun; Liu, Feng

    2013-11-15

    Bulk Fe{sub 83}B{sub 17} eutectic alloy rods with diameters up to 3 mm were prepared by undercooling solidification combined with Cu-mold casting. The results showed that the rapid solidification led to an increase in the nucleation rate, an inhibition of the grain growth and a competition between a stable Fe{sub 2}B phase and a metastable Fe{sub 3}B phase. Then, pure nano-lamellar eutectic microstructures and the metastable Fe{sub 3}B phase were successfully obtained in as-solidified alloys, which resulted in improved soft magnetic properties. - Highlights: • Pure nano-lamellar eutectic structure was directly formed in the bulk Fe-B alloys. • The metastable Fe{sub 3}B phase was directly formed in the bulk Fe-B alloys. • Undercooling solidification combined with Cu-mold casting was applied. • The information on bcc Fe, Fe{sub 2}B and Fe{sub 3}B-magnetism relationship was provided. • Nano-lamellar eutectic structures enhance the soft magnetic properties.

  6. Behaviour of oxygen-related thermal donors in Ge crystals Czochralski-grown from the melt covered fully by B{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Taishi, Toshinori [Institute of Carbon Science and Technology, Shinshu University, Wakasato, Nagano 380-8553 (Japan); Hashimoto, Yoshio [Faculty of Engineering, Shinshu University, Wakasato, Nagano 380-8553 (Japan); Ise, Hideaki; Murao, Yu; Ohsawa, Takayuki; Tokumoto, Yuki; Ohno, Yutaka; Yonenaga, Ichiro, E-mail: taishi@shinshu-u.ac.jp [Institute for Materials Research, Tohoku University, Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2011-02-01

    Oxygen-related thermal donors (OTDs) in oxygen-enriched Czochralski Ge crystals grown from a melt fully covered by B{sub 2}O{sub 3} liquid were investigated by infrared spectroscopy. Interstitially dissolved oxygen concentrations [O{sub i}] and thermal donor concentrations N{sub TD} in Ge specimens annealed at 350 deg. C for 64h and at 550 deg. C for 1h, followed by subsequent fast cooling to room temperature, were measured in comparison with those in as-grown Ge. By annealing at 350 deg. C, an absorption peak developed at 780 cm{sup -1} and the peak height at 855 cm{sup -1} related to [O{sub i}], decreased. The absorption coefficient at 780 cm{sup -1} showed the same correlation to the difference between the total concentration of oxygen atoms and the dissolved oxygen concentration in the annealed specimens. It was found that the number of oxygen atoms forming the OTD increases with increasing annealing time at 350 deg. C.

  7. Optimisation of soft magnetic properties in Fe-Cu-X-Si{sub 13}B{sub 9} (X=Cr, Mo, Zr) amorphous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Kwapulinski, P.; Rasek, J.; Stoklosa, Z.; Haneczok, G. E-mail: haneczok@us.edu.pl

    2001-09-01

    In the present paper a group of Fe-Cu-X-Si{sub 13}B{sub 9} (X=Cr, Mo, Zr) amorphous alloys has been examined by applying different experimental techniques--magnetic permeability, magnetic after-effect, coercive force and electrical resistivity measurements. It has been shown that their soft magnetic properties can be optimised by 1-h thermal annealing at the temperature close to the crystallisation temperature. This leads to an increase of permeability and a decrease of coercive force, thermal instability (magnetic after-effect intensity) and electrical resistivity of the material. The optimisation effect is discussed in terms of different processes--(i) a formation of a nanocrystalline phase with the grain size much smaller than the ferromagnetic exchange length, (ii) an annealing out of microvoids formed during the fabrication process and also (iii) a decrease of the effective magnetostriction constant. The temperature of optimisation annealing treatment is always higher than the Curie temperatures of the materials and varies approximately linearly with the atomic radius of the alloying additions.

  8. Electrochemical reduction of 2,4-dinitrophenol on nanocomposite electrodes modified with mesoporous silica and poly(vitamin B{sub 1}) films

    Energy Technology Data Exchange (ETDEWEB)

    Yang Ping; Cai Hui; Liu Shantang [School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430073 (China); Key Laboratory for Green Chemical Process of Ministry of Education, Wuhan 430073 (China); Hubei Key Lab of Novel Reactor and Green Chemical Technology, Wuhan 430073 (China); Wan Qijin, E-mail: qijinwan@mail.wit.edu.cn [School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430073 (China); Key Laboratory for Green Chemical Process of Ministry of Education, Wuhan 430073 (China); Hubei Key Lab of Novel Reactor and Green Chemical Technology, Wuhan 430073 (China); Wang Xiaoxia [Blumenstrasse 6, Gundelfingen 79194 (Germany); Yang Nianjun, E-mail: nianjun.yang@iaf.fraunhofer.de [Fraunhofer-Institute for Applied Solid State Physics (IAF), Freiburg 79108 (Germany)

    2011-08-01

    Electrochemical reduction of 2,4-dinitrophenol was investigated on a glassy carbon electrode modified with a nanocomposite Santa Barbara Amorphous silica (SBA-15) film and poly(vitamin B{sub 1}) film. For sensitive and selective detections, vanadium pentoxide and cerium oxide nanoparticles were incorporated into the matrix of SBA-15. 2,4-Dinitrophenol was reduced on the modified electrode at -0.39 and -0.25 V, corresponding to the reduction of 4-dinitrophenol and 2-dinitrophenol, respectively. Both cathodic peak currents were controlled by the diffusion of 2,4-dinitrophenol. The amplitude of the peak currents was proportional to the 2,4-dinitrophenol concentration in the range of 3.0-30 {mu}M. The modified electrode demonstrated a long lifetime for the detection of 2,4-dinitrophenol. The detection limit of 2,4-dinitrophenol was 0.5 {mu}M. Moreover, the modified electrode was used successfully to detect 2,4-dinitrophenol in lake water.

  9. Phase separation and crystallization process of amorphous Fe{sub 78}B{sub 12}Si{sub 9}Ni{sub 1} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Mukhgalin, V. V.; Lad’yanov, V. I. [Department of Structural-Phase Transformations, Physical Technical Institute, Ural Branch of the Russian Academy of Sciences, Kirov street 132, Izhevsk (Russian Federation)

    2015-08-17

    The influence of the melt heat treatment on the structure and crystallization process of the rapidly quenched amorphous Fe{sub 78}B{sub 12}Si{sub 9}Ni{sub 1} alloys have been investigated by means of x-ray diffraction, DSC and TEM. Amorphous phase separation has been observed in the alloys quenched after the preliminary high temperature heat treatment of the liquid alloy (heating above 1400°C). Comparative analysis of the pair distribution functions demonstrates that this phase separation accompanied by a changes in the local atomic arrangement. It has been found that crystallization process at heating is strongly dependent on the initial amorphous phase structure - homogeneous or phase separated. In the last case crystallization goes through the formation of a new metastable hexagonal phase [a=12.2849(9) Ǻ, c=7.6657(8) Ǻ]. At the same time the activation energy for crystallization (Ea) reduces from 555 to 475 kJ mole{sup −1}.

  10. Dependency of tunneling magneto-resistance on Fe insertion-layer thickness in Co{sub 2}Fe{sub 6}B{sub 2}/MgO-based magnetic tunneling junctions

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Kyo-Suk [MRAM Center, Department of Electronics and Computer Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Samsung Electronics Co., Ltd., San #16 Banwol-dong, Hwasung-City, Gyeonggi-Do 445-701 (Korea, Republic of); Park, Jea-Gun, E-mail: parkjgL@hanyang.ac.kr [MRAM Center, Department of Electronics and Computer Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2015-04-21

    For Co{sub 2}Fe{sub 6}B{sub 2}/MgO-based perpendicular magnetic tunneling junctions spin valves with [Co/Pd]{sub n}-synthetic-antiferromagnetic (SyAF) layers, the tunneling-magneto-resistance (TMR) ratio strongly depends on the nanoscale Fe insertion-layer thickness (t{sub Fe}) between the Co{sub 2}Fe{sub 6}B{sub 2} pinned layer and MgO tunneling barrier. The TMR ratio rapidly increased as t{sub Fe} increased up to 0.4 nm by improving the crystalline linearity of a MgO tunneling barrier and by suppressing the diffusion of Pd atoms from a [Co/Pd]{sub n}-SyAF. However, it abruptly decreased by further increasing t{sub Fe} in transferring interfacial-perpendicular magnetic anisotropy into the IMA characteristic of the Co{sub 2}Fe{sub 6}B{sub 2} pinned layer. Thus, the TMR ratio peaked at t{sub Fe} = 0.4 nm: i.e., 120% at 29 Ωμm{sup 2}.

  11. The ionic states of iodobenzene studied by photoionization and ab initio configuration interaction and DFT computations

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, Michael H., E-mail: m.h.palmer@ed.ac.uk, E-mail: tr01@staffmail.ed.ac.uk, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: malgorzata.biczysko@sns.it; Ridley, Trevor [School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, Scotland (United Kingdom); Hoffmann, Søren Vrønning; Jones, Nykola C. [ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Coreno, Marcello [CNR-IMIP, Montelibretti, c/o Laboratorio Elettra, Trieste (Italy); Simone, Monica de [CNR-IOM Laboratorio TASC, Trieste (Italy); Grazioli, Cesare [CNR-IOM Laboratorio TASC, Trieste (Italy); Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste (Italy); Biczysko, Malgorzata [National Research Council ICCOM-CNR, UOS di Pisa, Via G. Moruzzi 1, I-56124 Pisa (Italy); Scuola Normale Superiore, Piazza Cavalieri 7, 56126 Pisa (Italy); Baiardi, Alberto [Scuola Normale Superiore, Piazza Cavalieri 7, 56126 Pisa (Italy)

    2015-04-07

    New valence electron photoelectron spectra of iodobenzene obtained using synchrotron radiation have been recorded. Ionization energies (IEs) determined using multi-configuration SCF calculation (MCSCF) procedures confirmed the adiabatic IE order as: X{sup 2}B{sub 1}B{sub 2}B{sub 1}. Although it is convenient to retain C{sub 2v} labelling, there is an evidence that minor distortion to C{sub S} symmetry occurs at the MCSCF level for the C state. The fifth ionization process shown to be D{sup 2}A{sub 1} exhibits dissociation to C{sub 6}H{sub 5}{sup +} + I both in the experimental and theoretical studies. The calculated Franck-Condon vibrational spectral envelopes, including hot band contributions, for the first four ionic states reproduce the observed peak positions and intensities with reasonable accuracy. In order to simulate the observed spectra, different bandwidths are required for different states. The increase in the required bandwidths for the A{sup 2}A{sub 2} and B{sup 2}B{sub 2} states is attributed to internal conversion to lower-lying states. The presence of relatively high intensity sequence bands leads to asymmetry of each of the X{sup 2}B{sub 1} state bands.

  12. Study of boron carbide evolution under neutron irradiation; Contribution a l'etude de l'evolution du carbure de bore sous irradiation neutronique

    Energy Technology Data Exchange (ETDEWEB)

    Simeone, D. [CEA/Saclay, Dept. de Mecanique et de Technologie (DMT), 91 - Gif-sur-Yvette (France)]|[Universite Blaise Pascal, Clermont-Ferrand II, (CNRS), 63 - Aubiere (France)

    1999-07-01

    Owing to its high neutron efficiency, boron carbide (B{sub 4}C) is used as a neutron absorber in control rods of nuclear plants. Its behaviour under irradiation has been extensively studied for many years. It now seems clear that brittleness of the material induced by the {sup 10}B(n,{alpha}){sup 7}Li capture reaction is due to penny shaped helium bubbles associated to a high strain field around them. However, no model explains the behaviour of the material under neutron irradiation. In order to build such a model, this work uses different techniques: nuclear microprobe X-ray diffraction profile analysis and Raman and Nuclear Magnetic Resonance Spectroscopy to present an evolution model of B{sub 4}C under neutron irradiation. The use of nuclear reactions produced by a nuclear microprobe such as the {sup 7}Li(p,p'{gamma}){sup 7}Li reaction, allows to measure lithium profile in B{sub 4}C pellets irradiated either in Pressurised Water Reactors or in Fast Breeder Reactors. Examining such profiles enables us to describe the migration of lithium atoms out of B{sub 4}C materials under neutron irradiation. The analysis of X-ray diffraction profiles of irradiated B{sub 4}C samples allows us to quantify the concentrations of helium bubbles as well as the strain fields around such bubbles.Furthermore Raman spectroscopy studies of different B{sub 4}C samples lead us to propose that under neutron irradiation. the CBC linear chain disappears. Such a vanishing of this CBC chain. validated by NMR analysis, may explain the penny shaped of helium bubbles inside irradiated B{sub 4}C. (author)

  13. Numerical Study of Wake Vortex Interaction with the Ground Using the Terminal Area Simulation System

    Science.gov (United States)

    Proctor, Fred H.; Han, Jongil

    1999-01-01

    A sensitivity study for the in-ground effect on aircraft wake vortices has been conducted using a validated large eddy simulation model. The numerical results are compared with observed data and show good agreement for vortex decay and lateral vortex transport. The vortex decay rate is strongly influenced by the ground, but appears somewhat insensitive to ambient turbulence. In addition, the results show that the ground can affect the trajectory and descent-rate of a wake vortex pair at elevations up to about 3 b(sub o) (where b(sub o) is the initial vortex separation). However, the ground does not influence the average circulation of the vortices until the cores descend to within about 0.6 b(sub o), after which time the ground greatly enhances their rate of demise. Vortex rebound occurs in the simulations, but is more subtle than shown in previous numerical studies.

  14. Magnetostriction and {Delta}E effect of melt-spun (Fe{sub 81-x}Co{sub x}Ga{sub 19}){sub 80}B{sub 20} ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Jen, S. U. [Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 220, Taiwan (China); Wang, S. P. [Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 220, Taiwan (China); Chang, W. C. [Dept. of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China); Chang, H. W. [Dept. of Physics, Tunghai University, Taichung 407, Taiwan (China)

    2012-09-01

    (Fe{sub 81-x}Co{sub x}Ga{sub 19}){sub 80}B{sub 20} ribbons, with x = 0, 7, 11, 19, and 23, were made by the single-roller quenching method. The x-ray diffraction patterns showed the A2, D0{sub 19}, and L1{sub 2} diffraction peaks coexisting with the amorphous matrix background. When Fe was replaced by Co, i.e., when x was increased, the first crystallization temperature (T{sub X1}) and Curie temperature (T{sub C1}) rose greatly. With a sufficiently heavy load (or weight) stretching the ribbon downward, the magnetization M{sub S} was pulled along the vertical direction (i.e., the tension-axis). Then, by applying a horizontal field (H{sub E}) up to 6 KOe, we determined the sign and magnitude of the saturation magnetostriction ({lambda}{sub S}). The Young's modulus (E{sub S}) at magnetization saturation and {Delta}E effect was estimated from the stress-strain curve. We discovered that the stress-strain curve of (Fe{sub 81}Ga{sub 19}){sub 80}B{sub 20} exhibits the auxetic (or abnormal) characteristic with {Delta}E < 0. For the rest of the (Fe{sub 81-x}Co{sub x}Ga{sub 19}){sub 80}B{sub 20} with x {ne} 0, their stress-strain curves are normal with {Delta}E > 0. Because the sign of {lambda}{sub S} of the A2 phase is opposite to that of the D0{sub 19} and L1{sub 2} phases, {lambda}{sub S} of (Fe{sub 81-x}Co{sub x}Ga{sub 19}){sub 80}B{sub 20} is much reduced. However, {Delta}E/E{sub 0} Approximately-Equal-To-Or-The-Image-Of 36% is quite large for (Fe{sub 58}Co{sub 23}Ga{sub 19}){sub 80}B{sub 20}.

  15. Nuclear magnetic resonance studies of atomic motion in borohydride-based materials: Fast anion reorientations and cation diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Skripov, A.V., E-mail: skripov@imp.uran.ru; Soloninin, A.V.; Babanova, O.A.; Skoryunov, R.V.

    2015-10-05

    Highlights: • Solid solutions LiBH{sub 4}–LiI: extremely fast BH{sub 4} reorientations down to low T. • LiLa(BH{sub 4}){sub 3}Cl: Li-ion diffusive jumps and BH{sub 4} reorientations at the same frequency scale. • Dramatic acceleration of B{sub 12}H{sub 12} reorientations in the disordered phase of Na{sub 2}B{sub 12}H{sub 12}. • Fast Na-ion diffusion in the disordered phase of Na{sub 2}B{sub 12}H{sub 12}. - Abstract: Two basic types of thermally activated atomic jump motion are known to exist in solid borohydrides and the related systems: the reorientations of complex anions ([BH{sub 4}]{sup −}, [B{sub 12}H{sub 12}]{sup 2−}) and the translational diffusion of metal cations or complex anions. This paper reviews recent progress in nuclear magnetic resonance (NMR) studies of these jump processes in complex hydrides, such as solid solutions of halide anions in borohydrides, bimetallic borohydrides and borohydride–chlorides, borohydride–amides, and B{sub 12}H{sub 12}-based compounds. The emphasis is put on the systems showing fast-ion conductivity. For these systems, we discuss a possible relation between the reorientational motion of complex anions and the translational motion of metal cations.

  16. Effect of. cap alpha. -tocopherol, butylated-hydroxytoluene and hydroxy-anisole on the activation and binding of aflatoxin B/sub 1/ to macromolecules

    Energy Technology Data Exchange (ETDEWEB)

    Ch' ih, J.J.; Biedrzycka, D.; Devlin, T.M.

    1987-05-01

    The anti-oxidants, ..cap alpha..-tocopherol(TPA), butylated-hydroxy-toluene(BHT) and hydroxyanisole(BHA) inhibit the carcinogenic and toxic effects of a variety of chemical compounds, their effect on aflatoxin B/sub 1/ (AFB/sub 1/) activation and binding was examined utilizing rat liver microsomes and cells. With a NADPH generating system, oxygen, microsomes, (/sup 3/H)-AFB/sub 1/, 2.2 pmoles/h/mg protein was activated and bound to macromolecules. In hepatocytes, 3.4 and 1.4 pmoles of AFB/sub 1/ per 10/sup 6/ cells were taken up and bound to macromolecules, whereas the nucleic acid fraction contained 0.19 pmoles of bound AFB/sub 1/. Moderate decreases of AFB/sub 1/ activation and binding were observed when TPA was present in both cell-free and hepatocytes systems. Only in hepatocytes, BHT inhibited the AFB/sub 1/ uptake and binding to nucleic acids. BHA, however, inhibited microsomal activation of AFB/sub 1/ by 73%; maximum inhibition was reached at 1 mM. AFB/sub 1/ uptake, and binding to nucleic acids were inhibited by 65% and 79% by BHA. GSH-transferase activity of cells treated with these agents was not altered. The effect of BHA at various concentrations on AFB activation was compared with cytochrome P-450 inhibitors; the ED/sub 50/ of SKF 525A, BHA and metyrapone was 9 uM, 80 uM and 380 uM respectively. The data suggest that TPA, BHA and BHT exert their effect by different mechanisms.

  17. Circadian rhythm disturbance after radiotherapy for brain tumor in infantile period; Clinical effect of L-thyroxine and vitamin B[sub 12

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, Masaya; Shinozaki, Masako (Metropolitan Medical Center for the Severely Handicapped, Fuchu, Tokyo (Japan)); Sasaki, Hideo

    1993-08-01

    We report a 19-year-old man suffering from circadian sleep-wake (S-W) rhythm disturbance after total tumor resection and whole brain irradiation. The patient was diagnosed as having astrocytoma in the right temporal lobe by CT scan and angiography at the age of 6 months. After total tumor resection and whole brain irradiation ([sup 60]Co 60 Gy), he showed profound psychomotor retardation, endoclinologic dysfunction including hypothyroidism and growth hormone deficiency, and S-W rhythm disturbance. At age 19, brain MRI revealed asymmetrical low intensity in the hypothalamic region. On endoclinological examination panhypopituitarism due to primary hypothalamic lesion was evident. His S-W rhythm was disturbed; i.e., sleep periods were dispersedly distributed throughout 24 hours. He showed a lethargic tendency in the daytime. All-day polysomnography revealed abnormal sleep structure such as the absence of sleep spindle and hump, peripheral apnea, snoring and low oxygen saturation. After L-thyroxine supplementation his daily activity improved gradually. The decrease in short time sleep and tendency of a free-running rhythm were observed and oxygen saturation improved remarkably. Peripheral apnea and snoring disappeared. This wakening effect of L-thyroxine administration may be due to improvement of hypothyroidism symptom such as myxoedematous pharynx. It also seems related to the alteration of the central S-W rhythm regulation, because free-running rhythm appeared after L-thyroxine administration. Vitamin B[sub 12] (VB[sub 12]), which has been reported to be effective for S-W rhythm disorders, was not effective for our patient's free-running rhythm. Compared with the patients responding to VB[sub 12], our patient's organic brain damage was more evident radiologically and endoclinologically. Following the hypothesis that VB[sub 12] has a potential to reinforce the entrainment of circadian rhythm, our patient's organic brain damage may include entrainment

  18. Influence of production method on the magnetic parameters and structure of Fe{sub 61}Co{sub 10}Y{sub 8}Nb{sub 1}B{sub 20} amorphous alloys in the as-quenched state

    Energy Technology Data Exchange (ETDEWEB)

    Pietrusiewicz, Paweł, E-mail: pietrusiewicz@wip.pcz.pl [Czestochowa University of Technology, Faculty of Materials Processing Technology and Applied Physics, Institute of Physics, 19 Armii Krajowej Av., 42-200 Czestochowa (Poland); Nabiałek, Marcin; Dośpiał, Marcin; Gruszka, Konrad; Błoch, Katarzyna [Czestochowa University of Technology, Faculty of Materials Processing Technology and Applied Physics, Institute of Physics, 19 Armii Krajowej Av., 42-200 Czestochowa (Poland); Gondro, Joanna; Brągiel, Piotr [Jan Dlugosz University in Czestochowa, The Faculty of Mathematics and Natural Sciences, Institute of Physics, Armii Krajowej 13/15, 42-200 Czestochowa (Poland); Szota, Michał; Stradomski, Zbigniew [Czestochowa University of Technology, Faculty of Materials Processing Technology and Applied Physics, Materials Engineering Institute, 19 Armii Krajowej Av., 42-200 Czestochowa (Poland)

    2014-12-05

    Highlights: • The paper presents the influence of rapid quenching method on structure and magnetic properties. • Classical and bulk Fe-based amorphous alloy in the as-cast state. • Samples were obtained by the use of three casting methods i.e. suction, injection and melt-spinning. • XRD and Mössbauer effect studies were used to confirm amorphous structure of samples. • The reduction of saturation of magnetization in BMGs was resulting from higher packing density of atoms. - Abstract: In this paper, the influence of production method on the basic magnetic properties and structure of amorphous alloys, in the forms of ribbons and plates, was investigated. The samples used in the investigations were obtained by three different production methods: ultrafast cooling of the liquid alloy on a rotating copper wheel (the melt-spinning method), and the injection or suction of the molten alloy into a water-cooled copper die injection- and suction-casting, respectively. The structure of the resulting samples of Fe{sub 61}Co{sub 10}Y{sub 8}Nb{sub 1}B{sub 20} alloy was investigated by means of X-ray diffractometry, Mössbauer spectroscopy and scanning electron microscopy. The results of the microstructural investigations confirmed that the obtained samples were amorphous and without crystalline precipitations. The images from the scanning electron microscope were typical for amorphous materials. Magnetic measurements were performed using a vibrating sample magnetometer (VSM) using magnetic fields of up to 2 T. The highest value of the saturation magnetization was achieved for the sample which was in the form of a ribbon. The values of this parameter for the samples which were in the form of plates were similar to each other, regardless of the production method. The values of the coercivity showed much greater differences, depending on the production method. The smallest value of coercivity was found for the sample in plate-form obtained by injection-casting; this is

  19. Order-disorder transition of vortex matter in Mg{sub 0.9}B{sub 2}: anisotropic effects

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, A A M; Ortiz, W A [Grupo de Supercondutividade e Magnetismo, Departamento de Fisica, Universidade Federal de Sao Carlos, SP (Brazil); Sharma, P A; Hur, N; Cheong, S-W, E-mail: ana@df.ufscar.b, E-mail: ana@df.ufscar.b [Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers, NJ (United States)

    2009-03-01

    Third-harmonic susceptibility studies have been employed to probe the order-disorder transition of Vortex Matter of a magnesium-deficient sample of MgB{sub 2}. Our results reveal that the measured threshold is anisotropic for different orientations of the applied magnetic field, suggesting that the pinning efficiency of the magnesium-deficient regions depend on the orientation of the penetrated vortices.

  20. Spin fluctuations and alloying effects on low-temperature properties in BCC Asub(x)Bsub(1-x) compounds

    Energy Technology Data Exchange (ETDEWEB)

    Pictet, O.; Jarlborg, T.; Peter, M.

    1987-01-01

    A number of BCC alloys have been studied theoretically by self-consistent LMTO calculations using supercells of different sizes. To account for disorder effects a density-of-states broadening is used. Electron-phonon coupling, Stoner factors and superconducting transition temperatures have been calculated, including the effect of spin fluctuations. It is found that spin fluctuations are important for a good description of superconductivity. Moreover they can explain many experimental trends; in particular they show the increase of the transition temperature with pressure in NbZr compounds.

  1. Microstrucural characterization of gas atomized Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3}Cu{sub 1} and Fe{sub 97}Si{sub 3} alloys

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Escorial, A., E-mail: age@cenim.csic.es [CENIM-CSIC, Avda. Gregorio del Amo, 8, 28040 Madrid (Spain); Lieblich, M. [CENIM-CSIC, Avda. Gregorio del Amo, 8, 28040 Madrid (Spain); Lopez, M.; Marin, P. [Instituto de Magnetismo Aplicado, P.O. Box 155, 28230 Madrid (Spain)

    2011-06-15

    Research highlights: > Two FeSi-base alloys as precursors for small dimension soft magnets. > Small particles rapidly solidified by gas atomisation. > Increase effective magnetic anisotropy constant by alloying segregation. > Magnetic hardenning due to volume decrease. - Abstract: Powder particles of Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3}Cu{sub 1} and Fe{sub 97}Si{sub 3} soft magnetic alloys have been prepared by gas atomization. The gas atomized powder was microstructurally characterized and the dependence of coercivity with the composition and powder particle size investigated. As-atomized powder particles of both compositions were constituted by a bcc {alpha}-Fe (Si) solid solution. The Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3}Cu{sub 1} powder particles presented a grain microstructure with dendrite structure, which dendrite arms were enriched in Nb. The coercivity increased as the particle size decreased, with a minimum coercivity, of 5 Oe, measured in the Fe{sub 97}Si{sub 3} alloy in the range of 50-100 {mu}m powder particle size. The coercive fields were quite higher in the Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3}Cu{sub 1} than in the Fe{sub 97}Si{sub 3} powder, due to the Nb addition, which produced a phase segregation that leads to a noticeable magnetic hardening.

  2. Group 4 metal mono-dicarbollide piano stool complexes. Synthesis, structure, and reactivity of ({eta}{sup 5}-C{sub 2}B{sub 9}H{sub 11})M(NR{sub 2}){sub 2}(NHR{sub 2}) (M = Zr, R = Et; M = Ti, R = Me, Et)

    Energy Technology Data Exchange (ETDEWEB)

    Bowen, D.E.; Jordan, R.F. [Univ. of Iowa, Iowa City, IA (United States); Rogers, R.D. [Northern Illinois Univ., Dekalb, IL (United States)

    1995-08-01

    The amine elimination reaction of C{sub 2}B{sub 9}H{sub 13} and Zr(NEt{sub 2}){sub 4} yields the mono-dicarbollide complex ({eta}{sup 5}-C{sub 2}B{sub 9}H{sub 11})Zr(NEt{sub 2}){sub 2}(NHEt{sub 2}), (1), which has been shown to adopt a three-legged piano stool structure by X-ray crystallography. Crystal data for 1: space group P2{sub 1}/c, a = 10.704(4) A, b = 11.066(3) A, c = 20.382(8) A, {beta} = 99.20(3){degree}, V = 2383(1) A{sup 3}, Z = 4. Complex 1 undergoes facile ligand substitution by THF and 4-picoline, yielding ({eta}{sup 5}-C{sub 2}B{sub 9}H{sub 11})Zr(NEt{sub 2}){sub 2}-(THF) (2) and ({eta}{sup 5}-C{sub 2}B{sub 9}H{sub 11})Zr(NEt{sub 2}){sub 2}(4-picoline){sub 2} (3). Compound 3 exists as the four-coordinate species ({eta}{sup 5}-C{sub 2}B{sub 9}H{sub 11})Zr(NEt{sub 2}){sub 2}(4-picoline) in CH{sub 2}Cl{sub 2} solution. Complex 1 reacts selectively with 2 equiv of [NH{sub 2}ET{sub 2}]Cl, yielding ({eta}{sup 5}-C{sub 2}B{sub 9}H{sub 11})ZrCl{sub 2}(NHEt{sub 2}){sub 2} (4). Similarly, the reaction of C{sub 2}B{sub 9}H{sub 13} and Ti(NR{sub 2}){sub 4} yields ({eta}{sup 5}-C{sub 2}B{sub 9}H{sub 11})Ti(NR{sub 2}){sub 2}(NHR{sub 2}) (5, R = Me; 6, R = Et). Compounds 1-6 are potential precursors to group 4 metal ({eta}{sup 5}-C{sub 2}B{sub 9}H{sub 11})MR{sub 2}L{sub n} alkyl species. 25 refs., 3 figs., 3 tabs.

  3. Searching for new physics with B{sub s}{sup 0}{yields}K{sup ( Low-Asterisk )0}K{sup Macron ( Low-Asterisk )0} - A reappraisal

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Bhubanjyoti, E-mail: bhujyo@lps.umontreal.ca [Physique des Particules, Universite de Montreal, C.P. 6128, Succ. Centre-ville, Montreal, QC, H3C 3J7 (Canada); Datta, Alakabha, E-mail: datta@phy.olemiss.edu [Department of Physics and Astronomy, 108 Lewis Hall, University of Mississippi, Oxford, MS 38677-1848 (United States); Imbeault, Maxime, E-mail: mimbeault@cegep-st-laurent.qc.ca [Departement de Physique, Cegep de Saint-Laurent, 625, avenue Sainte-Croix, Montreal, QC, H4L 3X7 (Canada); London, David, E-mail: london@lps.umontreal.ca [Physique des Particules, Universite de Montreal, C.P. 6128, Succ. Centre-ville, Montreal, QC, H3C 3J7 (Canada)

    2012-10-31

    The effective phase 2{beta}{sub s}{sup eff} can be extracted from the indirect CP-violating asymmetry in B{sub s}{sup 0}{yields}K{sup ( Low-Asterisk )0}K{sup Macron ( Low-Asterisk )0}. In the standard model, 2{beta}{sub s}{sup eff} is expected to vanish, and so its measurement can potentially reveal the presence of new physics. However, there is a theoretical error if the second amplitude, V{sub ub}{sup Low-Asterisk }V{sub us}P{sub uc}{sup Prime }, is non-negligible. Ciuchini, Pierini and Silvestrini (CPS) have suggested measuring P{sub uc} in B{sub d}{sup 0}{yields}K{sup ( Low-Asterisk )0}K{sup Macron ( Low-Asterisk )0}, and relating it to P{sub uc}{sup Prime} using SU(3). For their choice of C{sub d} and S{sub d}, the direct and indirect CP asymmetries in B{sub d}{sup 0}{yields}K{sup ( Low-Asterisk )0}K{sup Macron ( Low-Asterisk )0}, they find that the error on 2{beta}{sub s}{sup eff} is very small, even allowing for 100% SU(3) breaking. In this Letter, we re-examine the CPS method, allowing for a large range of the B{sub d,s}{sup 0}{yields}K{sup ( Low-Asterisk )0}K{sup Macron ( Low-Asterisk )0} observables. We find that, if {radical}(C{sub d}{sup 2}+S{sub d}{sup 2}) is measured to be Less-Than-Or-Equivalent-To 0.4-0.5, the theoretical error on 2{beta}{sub s}{sup eff} is indeed small, 2-3 Degree-Sign . However, for other values of these observables, this error can be quite large, up to 14.9 Degree-Sign . This problem can be ameliorated if the values of SU(3) breaking were known, and we discuss different experimental ways of determining this quantity.

  4. Magnetic properties of the suction-cast bulk amorphous alloy: (Fe{sub 0.61}Co{sub 0.10}Zr{sub 0.025}Hf{sub 0.025}Ti{sub 0.02}W{sub 0.02}B{sub 0.20}){sub 96}Y{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Błoch, K., E-mail: bloch@wip.pcz.pl

    2015-09-15

    This paper presents the results of studies into the structural and magnetic properties of the bulk amorphous alloy: (Fe{sub 0.61}Co{sub 0.10}Zr{sub 0.025}Hf{sub 0.025}Ti{sub 0.02}W{sub 0.02}B{sub 0.20}){sub 96}Y{sub 4}, fabricated in the form of rods of length: 20 mm, and diameters: 1 mm and 2 mm. The samples were produced using the suction-casting method. The amorphicity of the investigated alloy, in the as-quenched state, was verified using X-ray diffractometry and Mössbauer spectroscopy. Studies of the magnetic susceptibility disaccommodation and the approach to magnetic saturation facilitated the conclusion that the investigated alloy, obtained in the form of rods of 2 mm diameter, can be characterized by a higher packing density of atoms; this was further confirmed by the results of Mössbauer spectroscopy. - Highlights: • Samples were obtained using using the suction-casting method. • The samples were manufactured in the shape of rods of diameters 1 mm and 2 mm. • The amorphous structure was confirmed using XRD and Mössbauer spectroscopy. • Magnetic properties were analyzed in terms of contents of structural defects. • Time stability of magnetic properties was studied by disaccommodation phenomenon.

  5. Parametric study on multiplanar K-joints made of RHS regarding axial force, in-plane bending and out-of-plane bending moments

    Energy Technology Data Exchange (ETDEWEB)

    Herion, S.; Mang, F. [Univ. of Karlsruhe (Germany)

    1994-12-31

    This paper presents the most significant results of a comprehensive parametric study on multiplanar K-joints. In this study, which is part of a pH. D. work, the influence of axial load, in-plane bending moments (IPB) and out-of-plane bending moments (OPB) are considered separately. For each type of loading, symmetric load vectors have been assumed and the most unfavorable assumption has been investigated. On this basis and in dependence of the geometric parameters {beta} = b{sub 1}/b{sub 0}, {tau} = t{sub 1}/t{sub 0}, 2{gamma} = b{sub 1}/t{sub 0}, SNCF diagrams and formulae for the design of multiplanar K-joints with gap made of RHS are given.

  6. Neutron-sensitive ZnS/{sup 10}B{sub 2}O{sub 3} ceramic scintillator detector as an alternative to a {sup 3}He-gas-based detector for a plutonium canister assay system

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T., E-mail: nakamura.tatsuya@jaea.go.jp [J-PARC, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Ohzu, A. [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Toh, K.; Sakasai, K.; Suzuki, H.; Honda, K. [J-PARC, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Birumachi, A.; Ebine, M. [Nuclear Science Institute, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Yamagishi, H. [J-PARC, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Takase, M.; Haruyama, M.; Kureta, M. [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Soyama, K. [J-PARC, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Nakamura, H. [Tokai Reprocessing Development Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Seya, M. [Integrated Support Center for Nuclear Nonproliferation and Nuclear Security, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan)

    2014-11-01

    A neutron-sensitive ZnS/{sup 10}B{sub 2}O{sub 3} ceramic scintillator detector was developed as an alternative to a {sup 3}He-gas-based detector for use in a plutonium canister assay system. The detector has a modular structure, with a flat ZnS/{sup 10}B{sub 2}O{sub 3} ceramic scintillator strip that is installed diagonally inside a light-reflecting aluminium case with a square cross-section, and where the scintillation light is detected using two photomultiplier tubes attached at both ends of the case. The prototype detectors, which have a neutron-sensitive area of 30 mm×250 mm, exhibited a sensitivity of 21.7–23.4±0.1 cps/nv (mean±SD) for thermal neutrons, a {sup 137}Cs gamma-ray sensitivity of 1.1–1.9±0.2×10{sup −7} and a count variation of less than 6% over the detector length. A trial experiment revealed a temperature coefficient of less than −0.24±0.05%/°C over the temperature range of 20–50 °C. The detector design and the experimental results are presented.

  7. Structural and electronic properties of zinc blende B{sub x}Al{sub 1-x}N{sub y}P{sub 1-y} quaternary alloys via first-principle calculations

    Energy Technology Data Exchange (ETDEWEB)

    Abdiche, A., E-mail: abdiche_a@yahoo.fr [Engineering Physics Laboratory, Tiaret University, 14000 Tiaret (Algeria); Baghdad, R. [Engineering Physics Laboratory, Tiaret University, 14000 Tiaret (Algeria); Khenata, R., E-mail: khenata_rabah@yahoo.fr [Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M), Departement de Technologie, Universite de Mascara, 29000 Mascara (Algeria); Department of Physics and Astronomy, King Saud University, P.O Box 2455, Riyadh 11451 (Saudi Arabia); Riane, R. [Computational Materials Science Laboratory, University Research of Sidi-Bel-Abbes, 22000 Algeria (Algeria); Al-Douri, Y. [Institute of Nono Electronic Engineering, University Malaysia Perlis, 01000 Kangar, Perlis (Malaysia); Guemou, M. [Engineering Physics Laboratory, Tiaret University, 14000 Tiaret (Algeria); Bin-Omran, S. [Department of Physics and Astronomy, King Saud University, P.O Box 2455, Riyadh 11451 (Saudi Arabia)

    2012-02-01

    The structural and electronic properties of cubic zinc blende BN, BP, AlN and AlP compounds and their B{sub x}Al{sub 1-x}N{sub y}P{sub 1-y} quaternary alloys, have been calculated using the non relativistic full-potential linearized-augmented plane wave FP-LAPW method. The exchange-correlation potential is treated with the local density approximation of Perdew and Wang (LDA-PW) as well as the generalized gradient approximation (GGA) of Perdew-Burke and Ernzerhof (GGA-PBE). The calculated structural properties of BN, BP, AlN and AlP compounds are in good agreement with the available experimental and theoretical data. A nonlinear variation of compositions x and y with the lattice constants, bulk modulus, direct and indirect band gaps is found. The calculated bowing of the fundamental band gaps is in good agreement with the available experimental and theoretical value. To our knowledge this is the first quantitative theoretical investigation on B{sub x}Al{sub 1-x}N{sub y}P{sub 1-y} quaternary alloy and still awaits experimental confirmations.

  8. /sup 59/Fe and /sup 58/Co-vitamin B/sub 12/ absorptions studies in radiotherapy of collum carcinomas by whole-body radiometry

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, M.A.; Bolovin, L.M.; Verkhovskaya, N.I.; Mel' nikova, L.N. (Nauchno-Issledovatel' skij Inst. Metallurgii, Chelyabinsk (USSR)); Yavor, T.; Bero, T. (Orvostudomanyi Egyetem, Pecs (Hungary))

    1983-01-01

    The results of examination of iron and vitamin B-12 metabolism in the radiotherapy of collum carcinomas are reported. The absorption of iron and vitamin B-12 was found to decrease under the influence of radiotherapy. The degree of the absorption decrease depends on the radiation dose.

  9. Intermediate valence in single crystals of (Lu{sub 1−x}Y b{sub x}){sub 3}Rh{sub 4}Ge{sub 13} (0 ≤ x ≤ 1)

    Energy Technology Data Exchange (ETDEWEB)

    Rai, Binod K.; Morosan, E. [Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States)

    2015-04-01

    Single crystals of (Lu{sub 1−x}Y b{sub x}){sub 3}Rh{sub 4}Ge{sub 13} were characterized by magnetization, specific heat, and electrical resistivity measurements. Doping Yb into the non-magnetic Lu{sub 3}Rh{sub 4}Ge{sub 13} compound tunes this cubic system’s properties from a superconductor with disordered metal normal state (x < 0.05) to a Kondo for 0.05 ≤ x ≤0.2 and intermediate valence at the highest Yb concentrations. The evidence for intermediate Yb valence comes from a broad maximum in the magnetic susceptibility and X-ray photoelectron spectroscopy. Furthermore, the resistivity displays a local maximum at finite temperatures at intermediate compositions x, followed by apparent metallic behavior closest to the Yb end compound in the series.

  10. Search for the rare decays B{sub s}{sup 0}{yields}{mu}{sup +}{mu}{sup -} and B{sup 0}{yields}{mu}{sup +}{mu}{sup -}

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alessio, F. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Amoraal, J. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); Arrabito, L. [CC-IN2P3, CNRS/IN2P3, Lyon-Villeurbanne (France); Artuso, M. [Syracuse University, Syracuse, NY (United States); Aslanides, E. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France)

    2011-05-23

    A search for the decays B{sub s}{sup 0}{yields}{mu}{sup +}{mu}{sup -} and B{sup 0}{yields}{mu}{sup +}{mu}{sup -} is performed with about 37 pb{sup -1} of pp collisions at {radical}(s)=7 TeV collected by the LHCb experiment at the Large Hadron Collider at CERN. The observed numbers of events are consistent with the background expectations. The resulting upper limits on the branching ratios are B(B{sub s}{sup 0}{yields}{mu}{sup +}{mu}{sup -})<5.6x10{sup -8} and B(B{sup 0}{yields}{mu}{sup +}{mu}{sup -})<1.5x10{sup -8} at 95% confidence level.

  11. Correlation between thermal induced structural and magnetic transformations in Si-rich Fe{sub 73}Cu{sub 1}Si{sub 16}B{sub 7}Nb{sub 3} metal alloy

    Energy Technology Data Exchange (ETDEWEB)

    Brzozowski, Romuald, E-mail: rbrzozowski@phys.uni.lodz.pl [Uniwersytet Lodzki, Katedra Fizyki Jadrowej, Pomorska 149, PL 90-236 Lodz (Poland); Moneta, Marek E. [Uniwersytet Lodzki, Katedra Fizyki Ciala Stalego, Pomorska 149, PL 90-236 Lodz (Poland)

    2012-05-15

    Properties of amorphous Fe{sub 73}Cu{sub 1}Si{sub 16}B{sub 7}Nb{sub 3} foil, the Si rich metal alloy, and the foils partly crystallised after annealing, were analysed structurally and magnetically in the temperature range from 4 to 1000 K. The Fe (Si) and Fe (B) structures were identified and characterised with the crystallisation temperatures: 750 and 893 K, activation energies 460 and 580 kJ/mol. The Curie temperatures for amorphous structure: 613 K and for crystalline structures: 820, 875, 920 and 980 K were determined. It was found and analysed a delay of the sample magnetisation, determined by thermomagnetometry, with respect to structural crystallisation, determined by scanning calorimetry, which was correlated with magnetic hyperfine field, determined by transmission Moessbauer spectroscopy.

  12. Atomic packing and diffusion in Fe{sub 85}Si{sub 2}B{sub 9}P{sub 4} amorphous alloy analyzed by ab initio molecular dynamics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yaocen; Takeuchi, Akira; Makino, Akihiro [Institute for Material Research, Tohoku University, Sendai 980-8577 (Japan); Liang, Yunye [New Industry Creation Hatchery Center, Tohoku University, Sendai 980-8579 (Japan); Kawazoe, Yoshiyuki [New Industry Creation Hatchery Center, Tohoku University, Sendai 980-8579 (Japan); Kutateladze Institute of Thermophysics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk (Russian Federation)

    2015-05-07

    In the work reported in this paper, ab initio molecular dynamics simulation was performed on Fe{sub 85}Si{sub 2}B{sub 9}P{sub 4} amorphous alloy. Preferred atomic environment of the elements was analyzed with Voronoi polyhedrons. It showed that B and P atoms prefer less neighbors compared with Fe and Si, making them structurally incompatible with Fe rich structure and repulsive to the formation of α-Fe. However, due to the low bonding energy of B and P caused by low coordination number, the diffusion rates of them were considerably large, resulting in the requirement of fast annealing for achieving optimum nano-crystallization for its soft magnetic property. The simulation work also indicates that diffusion rate in amorphous alloy is largely determined by bonding energy rather than atomic size.

  13. Crossrelaxations and non-radiative energy transfer from ({sup 4}G{sub 5/2}) Sm{sup 3+} → ({sup 5}D{sub 0}) Eu{sup 3+}: B{sub 2}O{sub 3}–ZnO glasses

    Energy Technology Data Exchange (ETDEWEB)

    Naresh, V., E-mail: varna.naresh@gmail.com; Rudramadevi, B.H.; Buddhudu, S., E-mail: profsb_svuniv@hotmail.com

    2015-05-25

    Graphical abstract: The energy transfer process occurring from Sm{sup 3+} to Eu{sup 3+} in B{sub 2}O{sub 3}–ZnO (BZn) glasses is analyzed. Based on the Foster–Dexter theory, the possibility of energy transfer between Sm{sup 3+} and Eu{sup 3+} has been demonstrated from the spectral overlap of Eu{sup 3+} absorption and Sm{sup 3+} emission, photoluminescence spectra, energy level diagram and lifetime measurements. The energy transfer mechanism in (Sm{sup 3+} + Eu{sup 3+}) co-doped glass is governed by dipole–dipole interaction. - Highlights: • Spectroscopic properties of individually doped Sm{sup 3+}, Eu{sup 3+} & co-doped (Sm{sup 3+} + Eu{sup 3+}) in BZn glasses were studied separately. • The effect of Eu{sup 3+} concentration on luminescence properties is explained from cross-relaxations. • Energy transfer from Sm{sup 3+} ({sup 4}G{sub 5/2}) to Eu{sup 3+} ({sup 5}D{sub 0}) has been explained from Foster–Dexter theory. • Dipole–dipole mechanism governs the energy transfer from Sm{sup 3+} to Eu{sup 3+}. - Abstract: The present paper reports on the results concerning to photoluminescence features of Eu{sup 3+}, Sm{sup 3+} ions and energy transfer process occurring from Sm{sup 3+} to Eu{sup 3+} doped in 45 B{sub 2}O{sub 3}–55 ZnO (BZn) glasses prepared by melt quenching technique. Luminescence quenching as a function of Eu{sup 3+} concentration in BZn glasses has been discussed. Among the studied concentrations, 0.5 mol% of Eu{sup 3+} is optimized because it has exhibited red emission transition {sup 5}D{sub 0} → {sup 7}F{sub 2}. With regard to Sm{sup 3+} glasses, orange emission at 602 nm ({sup 4}G{sub 5/2} → {sup 6}H{sub 7/2}) has been noticed on exciting with λ{sub exci} = 403 nm. Based on the Foster–Dexter theory, the possibility of energy transfer between Sm{sup 3+} and Eu{sup 3+} has been explained from the spectral overlap of Eu{sup 3+} absorption and Sm{sup 3+} emission. The optimized concentration 0.5 mol% of Eu{sup 3+} is co

  14. Ultra-soft magnetic properties and correlated phase analysis by {sup 57}Fe Mössbauer spectroscopy of Fe{sub 74}Cu{sub 0.8}Nb{sub 2.7}Si{sub 15.5}B{sub 7} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Manjura Hoque, S.; Liba, S. I.; Akhter, Shireen [Materials Science Division, Atomic Energy Centre, Dhaka 1217 (Bangladesh); Anirban, A. [Semiconductor Physics Group, University of Cambridge (United Kingdom); Choudhury, Shamima [Department of Physics, University of Dhaka, Dhaka 1217 (Bangladesh)

    2016-02-15

    A detailed study of magnetic softness has been performed on FINEMENT type of ribbons by investigating the BH loop with maximum applied field of 960 A/m. The ribbon with the composition of Fe{sub 74}Cu{sub 0.8}Nb{sub 2.7}Si{sub 15.5}B{sub 7} was synthesized by rapid solidification technique and the compositions volume fraction was controlled by changing the annealing condition. Detail phase analysis was performed through X-ray diffraction (XRD), Differential scanning calorimetry (DSC), Vibrating sample magnetometer (VSM) and Mössbauer spectroscopy in order to correlate the ultrasoft magnetic properties with the volume fraction of amorphous and α-Fe(Si) soft nano composites. Bright (BF) and dark field (DF) image with selective area diffraction (SAD) patterns by the transmission electron microscopy (TEM) of the sample annealed for the optimized annealed condition at 853 K for 3 min reveals nanocrystals with an average size between 10-15 nm possessing the bcc structure which matches with the grain size revealed by the X-ray diffraction. Kinetics of crystallization of α-Fe(Si) phases has been determined by DSC curves. Extremely small coercivity of 30.9 A/m and core loss of 2.5 W/Kg for the sample annealed at 853 K for 3 min was found. Similar values for other crystalline conditions were determined by using BH loop tracer with a maximum applied field of around 960 A/m. Mössbauer spectroscopy was used to determine chemical shift, hyperfine field distribution (HFD), and peak width of different phases. The volume fractions of the relative amount of amorphous and crystalline phases are also determined by Mössbauer spectroscopy. High saturation magnetization along with ultrasoft magnetic properties exhibits very high potentials technological applications.

  15. The complex metal-rich boride Ti{sub 1+x}Rh{sub 2-x+y}Ir{sub 3-y}B{sub 3} (x=0.68, y=1.06) with a new structure type containing B{sub 4} zigzag fragments: Synthesis, crystal chemistry and theoretical calculations

    Energy Technology Data Exchange (ETDEWEB)

    Goerens, Christian [Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52064 Aachen (Germany); Fokwa, Boniface P.T., E-mail: boniface.fokwa@ac.rwth-aachen.de [Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52064 Aachen (Germany)

    2012-08-15

    Polycrystalline samples and single crystals of the new complex boride Ti{sub 1+x}Rh{sub 2-x+y}Ir{sub 3-y}B{sub 3} (x=0.68; y=1.06) were synthesized by arc-melting the elements in a water-cooled copper crucible under an argon atmosphere and characterized by X-Ray diffraction as well as EDX measurements. The crystal structure was refined on the basis of single crystal data. The new phase, which represents a new structure type containing trans zigzag B{sub 4} fragments as well as isolated boron atoms crystallizes in the orthorhombic space group Pbam (Nr. 55) with the lattice parameters a=8.620(1) A, b=14.995(2) A and c=3.234(1) A. First-principles density functional theory calculations using the Vienna ab-initio simulation package (VASP) were performed on an appropriate structural model (using a supercell approach) and the experimental crystallographic data could be reproduced accurately. Based on this model, the density of states and crystal orbital Hamilton population (for bonding analysis) were calculated, using the linear muffin-tin orbital atomic sphere approximation (LMTO-ASA) method. According to these calculations, this metal-rich compound should be metallic, as expected. Furthermore, very strong boron-boron interactions are observed in the trans zigzag B{sub 4} fragment, which induce a clear differentiation of two types of metal-boron contacts with different strength. The observed three-dimensional metal-metal interaction is in good agreement with the predicted metallic behavior. - graphical abstract: The structure of Ti{sub 1.68(2)}Rh{sub 2.38(6)}Ir{sub 1.94(4)} B{sub 3}, a new structure type containing planar trans zigzag B{sub 4} units, is another example which illustrates the tendency of metal-rich borides to form B-B bonds with increasing boron content. Beside the B{sub 4} fragment it exhibits one-dimensional chains of titanium atoms and hold one-dimensional strings of face-sharing empty tetrahedral and square pyramidal clusters (see figure). Highlights

  16. Millimeter-wave optical double resonance schemes for rapid assignment of perturbed spectra, with applications to the C{sup ~} {sup 1}B{sub 2} state of SO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Park, G. Barratt, E-mail: barratt@mit.edu, E-mail: barratt.park@gmail.com; Womack, Caroline C.; Jiang, Jun; Field, Robert W., E-mail: rwfield@mit.edu [Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Whitehill, Andrew R.; Ono, Shuhei [Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2015-04-14

    Millimeter-wave detected, millimeter-wave optical double resonance (mmODR) spectroscopy is a powerful tool for the analysis of dense, complicated regions in the optical spectra of small molecules. The availability of cavity-free microwave and millimeter wave spectrometers with frequency-agile generation and detection of radiation (required for chirped-pulse Fourier-transform spectroscopy) opens up new schemes for double resonance experiments. We demonstrate a multiplexed population labeling scheme for rapid acquisition of double resonance spectra, probing multiple rotational transitions simultaneously. We also demonstrate a millimeter-wave implementation of the coherence-converted population transfer scheme for background-free mmODR, which provides a ∼10-fold sensitivity improvement over the population labeling scheme. We analyze perturbations in the C{sup ~} state of SO{sub 2}, and we rotationally assign a b{sub 2} vibrational level at 45 328 cm{sup −1} that borrows intensity via a c-axis Coriolis interaction. We also demonstrate the effectiveness of our multiplexed mmODR scheme for rapid acquisition and assignment of three predissociated vibrational levels of the C{sup ~} state of SO{sub 2} between 46 800 and 47 650 cm{sup −1}.

  17. Search for the rare decays B{sub s}{sup 0}{yields}{mu}{sup +}{mu}{sup -} and B{sup 0}{yields}{mu}{sup +}{mu}{sup -}

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Aquines Gutierrez, O. [Max-Planck-Institut fuer Kernphysik (MPIK), Heidelberg (Germany); Archilli, F. [Laboratori Nazionali dell' INFN di Frascati, Frascati (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Arrabito, L. [CC-IN2P3, CNRS/IN2P3, Lyon-Villeurbanne (France); and others

    2012-02-14

    A search for the decays B{sub s}{sup 0}{yields}{mu}{sup +}{mu}{sup -} and B{sup 0}{yields}{mu}{sup +}{mu}{sup -} is performed with 0.37 fb{sup -1} of pp collisions at {radical}(s)=7 TeV collected by the LHCb experiment in 2011. The upper limits on the branching fractions are B(B{sub s}{sup 0}{yields}{mu}{sup +}{mu}{sup -})<1.6 Multiplication-Sign 10{sup -8} and B(B{sup 0}{yields}{mu}{sup +}{mu}{sup -})<3.6 Multiplication-Sign 10{sup -9} at 95% confidence level. A combination of these results with the LHCb limits obtained with the 2010 dataset leads to B(B{sub s}{sup 0}{yields}{mu}{sup +}{mu}{sup -})<1.4 Multiplication-Sign 10{sup -8} and B(B{sup 0}{yields}{mu}{sup +}{mu}{sup -})<3.2 Multiplication-Sign 10{sup -9} at 95% confidence level.

  18. A correlation between the magnetic and structural properties of isochronally annealed Cu-free FINEMET alloy with composition Fe{sub 72}B{sub 19.2}Si{sub 4.8}Nb{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, A.K.; Singh, M.N.; Upadhyay, Anuj [Raja Ramanna Centre for Advanced Technology, Indus Synchrotrons Utilization Division, Indore (India); Satalkar, M.; Shah, M.; Kane, S.N. [D. A. University, Magnetic Materials Laboratory, School of Physics, Indore (India); Ghodke, N. [UGC-DAE Consortium for Scientific Research, Indore (India); Varga, L.K. [RISSPO, Hungarian Academy of Sciences, P.O. Box 49, Budapest (Hungary)

    2014-08-24

    In this paper, structural changes in Cu-free FINEMET alloy (Fe{sub 72}B{sub 19.2}Si{sub 4.8}Nb{sub 4}) invoked by isochronal thermal annealing were investigated by synchrotron X-ray diffraction (SXRD) and X-ray absorption near-edge spectroscopy techniques. Detailed radial distribution function analysis of SXRD data showed that the first coordination shell in the amorphous matrix is preserved for annealing up to 400 C (1 h), whereas changes were observed in the second coordination shell. Annealing at 600 C (1 h) showed crystalline phase emanating over the amorphous background in SXRD data and a corresponding large decrease in the width of the first coordination shell. The width of the second coordination shell decreased with increasing annealing temperature. The magnetic properties such as remanence field, saturation magnetization and loss were found to have a positive correlation with the changes in the structural parameters of the second coordination shell, for all the samples (as quenched as well as annealed at various temperatures). We propose that the rearrangement of magnetic amorphous matrix on annealing also contributes to modifying the exchange interaction between ferromagnetic nanocrystalline domains and hence changes magnetic parameters, in addition to the growth of these domains, on annealing. (orig.)

  19. Magnetic properties and loss separation in Fe{sub 76−x}Ag{sub x}Nb{sub 2}Si{sub 13}B{sub 9} amorphous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Stokłosa, Z., E-mail: zbigniew.stoklosa@us.edu.pl; Kwapuliński, P.; Rasek, J.; Haneczok, G.; Kubisztal, M.

    2015-06-15

    Highlights: • Soft magnetic properties can be optimized by applying a suitable heat treatment. • Low field magnetic permeability of the optimized samples increases about 10 times. • Total magnetic loss of the optimized samples decreases at least 10 times. • Plasticity is much higher than that reported for similar nanocrystalline alloys. • Observed effects are attributed to formation of the relaxed amorphous phase. - Abstract: Some selected properties (magnetic, plastic, elastic) in amorphous Fe{sub 76−x}Ag{sub x}Nb{sub 2}Si{sub 13}B{sub 9} (x = 0.5, 0.75, 1.0) alloys, obtained by melt spinning technique, are presented and discussed in detail. It was shown that a suitable heat treatment of the as quenched samples (i.e. the optimization annealing) leads to a significant improvement of soft magnetic properties (permeability increases at least 10 times). The observed effect is attributed to formation of the so-called relaxed amorphous phase free of iron nanograins. Special attention is paid for loss separation into different components: hysteresis loss, eddy-current loss and residual loss. The latter effect can be attributed to diffusion of free volume and practically disappear after the optimization annealing.

  20. Synthesis, crystal structure, and properties of an interesting elliptical vanadoborate housing crystal: [Ni(en){sub 2}]{sub 6}[(VO){sub 12}O{sub 6}B{sub 18}O{sub 39}(OH){sub 3}]·5H{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xiangzhan; Dong, Xiaoyu [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Technical Institute of Physics and Chemistry of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, 830011 Urumqi (China); Key Laboratory at Universities of Education Department of Xinjiang Uygur Autonomous Region for New Energy Materials, Xinjiang Institute of Engineering, 830091 Urumqi (China); Pan, Shilie, E-mail: slpan@ms.xjb.ac.cn [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Technical Institute of Physics and Chemistry of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, 830011 Urumqi (China); Han, Jian, E-mail: hanjian@ms.xjb.ac.cn [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Technical Institute of Physics and Chemistry of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, 830011 Urumqi (China); Yang, Yun; Zhang, Fangyuan; Yu, Hongwei [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Technical Institute of Physics and Chemistry of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, 830011 Urumqi (China)

    2015-03-05

    Highlights: • We synthesize a new organic–inorganic vanadoborate under a hydrothermal condition. • The crystal contains a novel elliptical housing with V{sub 12}B{sub 18}O{sub 60} clusters. • The physical and chemical properties of the crystal are described. - Abstract: A new vanadoborate, [Ni(en){sub 2}]{sub 6}[(VO){sub 12}O{sub 6}B{sub 18}O{sub 39}(OH){sub 3}]·5H{sub 2}O, has been synthesized under a hydrothermal condition. It crystallizes into rhombohedral crystal system with centrosymmetric space group of R3{sup ‾} with a = 20.824(7) Å, c = 21.050(14) Å, Z = 3. The crystal contains a novel elliptical housing with V{sub 12}B{sub 18}O{sub 60} clusters. Around the housing, there is six nickel atoms coordinated with two ethylenediamine molecules. The oxidation states of vanadium in the compound are V(IV) and V(V). The characterizations by powder X-ray diffraction, infrared spectroscopy, UV–Vis diffuse reflectance spectrum, and TG curve are also described.

  1. Synthesis, crystal structure and properties of Mg{sub 3}B{sub 36}Si{sub 9}C and related rare earth compounds RE{sub 3−x}B{sub 36}Si{sub 9}C (RE=Y, Gd–Lu)

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Thilo; Pediaditakis, Alexis; Sagawe, Vanessa [Albert-Ludwigs-Universität Freiburg, Institut für Anorganische und Analytische Chemie, Albertstr. 21, D-79104 Freiburg (Germany); Freiburger Materialforschungszentrum FMF, Stefan-Maier-Str. 25, D-79104 Freiburg (Germany); Hillebrecht, Harald, E-mail: harald.hillebrecht@ac.uni-freiburg.de [Albert-Ludwigs-Universität Freiburg, Institut für Anorganische und Analytische Chemie, Albertstr. 21, D-79104 Freiburg (Germany); Freiburger Materialforschungszentrum FMF, Stefan-Maier-Str. 25, D-79104 Freiburg (Germany)

    2013-08-15

    We report on the synthesis and characterisation of Mg{sub 3}B{sub 36}Si{sub 9}C. Black single crystals of hexagonal shape were yielded from the elements at 1600 °C in h-BN crucibles welded in Ta ampoules. The crystal structure (space group R3{sup ¯}m, a=10.0793(13) Å, c=16.372(3) Å, 660 refl., 51 param., R{sub 1}(F)=0.019; wR{sub 2}(F{sup 2})=0.051) is characterized by a Kagome-net of B{sub 12} icosahedra, ethane like Si{sub 8}-units and disordered SiC-dumbbells. Vibrational spectra show typical features of boron-rich borides and Zintl phases. Mg{sub 3}B{sub 36}Si{sub 9}C is stable against HF/HNO{sub 3} and conc. NaOH. The micro-hardness is 17.0 GPa (Vickers) and 14.5 GPa (Knoop), respectively. According to simple electron counting rules Mg{sub 3}B{sub 36}Si{sub 9}C is an electron precise compound. Band structure calculations reveal a band gap of 1.0 eV in agreement to the black colour. Interatomic distances obtained from the refinement of X-ray data are biased and falsified by the disorder of the SiC-dumbbell. The most evident structural parameters were obtained by relaxation calculation. Composition and carbon content were confirmed by WDX measurements. The small but significant carbon content is necessary by structural reasons and frequently caused by contaminations. The rare earth compounds RE{sub 3−x}B{sub 36}Si{sub 9}C (RE=Y, Dy–Lu) are isotypic. Single crystals were grown from a silicon melt and their structures refined. The partial occupation of the RE-sites fits to the requirements of an electron-precise composition. According to the displacement parameters a relaxation should be applied to obtain correct structural parameters. - Graphical abstract: Single crystals of the new boridesilicide Mg{sub 3}B{sub 36}Si{sub 9}C were obtained from the elements in a Si-melt. Besides B{sub 12}-icosahedra and ethan-like Si{sub 8}-units it contains a disordered SiC-dumbbell. Correct distances were obtained by relaxation calculation based on the X-ray data

  2. Constraints on exclusive branching fractions B{sub i}(B{sup +} → X{sub c}{sup i}l{sup +}ν) from moment measurements in inclusive B → X{sub c}lν decays

    Energy Technology Data Exchange (ETDEWEB)

    Bernlochner, Florian U.; Lueck, Thomas [University of Victoria, Victoria, British Columbia (Canada); Biedermann, Dustin; Lacker, Heiko [Institut fuer Physik, Humboldt Universitaet zu Berlin, Berlin (Germany)

    2014-06-15

    As an alternative to direct measurements, we extract the branching fractions B{sub i}(B{sup +} → X{sub c}{sup i}l{sup +}ν) with X{sub c}{sup i} = D, D{sup *}, D{sub 0}, D{sub 1}{sup '}, D{sub 1}, D{sub 2}, D{sup '}, D{sup '*} and non-resonant final states (D{sup (*)}π){sub nr}, from a fit to electron energy, hadronic mass and combined hadronic mass.energy moments measured in inclusive B → X{sub c}lν decays. The fit is performed by constraining the sum of exclusive branching fractions to the measured B(B{sup +} → X{sub c}l{sup +}ν) value, and with different sets of additional constraints for the directly measured branching fractions. There is no fit scenario in which a single branching fraction can close the gap between B(B{sup +} → X{sub c}l{sup +}ν) and the sum of known branching fractions B{sub i}(B{sup +} → X{sub c}{sup i}l{sup +}ν). The fitted B(B{sup +} → anti D{sup *0}l{sup +}ν) is found to be significantly larger than its direct measurement. B(B{sup +} → anti D{sup 0}l{sup +}ν) is in good agreement with the direct measurement; when B(B{sup +} → anti D{sup *0}l{sup +}ν) is constrained the fitted B(B{sup +} → anti D{sup 0}l{sup +}ν) increases. Within large uncertainties, B(B{sup +} → anti D{sub 1}{sup '0}l{sup +}ν) agrees with direct measurements. Depending on the fit scenario, B(B{sup +} → anti D{sub 0}{sup 0}l{sup +}ν) is consistent with or larger than its direct measurement. The fit is not able to easily disentangle B{sup +} → anti D{sub 1}{sup 0}l{sup +}ν and B{sup +} → anti D{sub 2}{sup 0}l{sup +}ν, and tends to increase the sum of these two branching fractions. B(B{sup +} → (D{sup (*)}π){sub nr}l{sup +}ν) with nonresonant (D{sup (*)}π){sub nr} final states is found to be of the order 0.3 %. No indication is found for significant contributions from so far unmeasured B{sup +} → anti D{sup '(*)0}l{sup +}ν decays. (orig.)

  3. Flavour physics in the littlest Higgs model with T-parity: effects in the K, B{sub d/s} and D systems

    Energy Technology Data Exchange (ETDEWEB)

    Recksiegel, S. [Technische Universitaet Muenchen, Physikdepartment, T31, James-Franck-Str. 1, 85748 Garching (Germany)

    2010-07-15

    The Littlest Higgs Model with T parity (LHT) is an interesting alternative model for New Physics at the TeV scale. Although Flavour Physics was not the reason for creating the LHT model, significant effects (such as large CP violation where not predicted by the SM) can be created without violating existing experimental bounds. We study the B-, K- and especially the D-sector. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  4. Kinin B>1 receptors mediate depression-like behavior response in stressed mice treated with systemic E. coli lipopolysaccharide

    OpenAIRE

    Campos Maria M; Siqueira Jarbas M; Figueiredo Claudia P; Dornelles Fabiana N; Maciel Izaque S; Viana Alice F; Calixto João B

    2010-01-01

    Abstract Background Kinin B1 receptors are inducible molecules up-regulated after inflammatory stimuli. This study evaluated the relevance of kinin B1 receptors in a mouse depression behavior model. Methods Mice were exposed to a 5-min swimming session, and 30 min later they were injected with E. coli lipopolysaccharide (LPS). Depression-like behavior was assessed by determining immobility time in a tail suspension test. Different brain structures were collected for molecular and immunohistoc...

  5. Analysis of cellular responses to aflatoxin B{sub 1} in yeast expressing human cytochrome P450 1A2 using cDNA microarrays

    Energy Technology Data Exchange (ETDEWEB)

    Guo Yingying [Departmental of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA (United States); Fred Hutchinson Cancer Research Center, Seattle, WA (United States); Breeden, Linda L. [Fred Hutchinson Cancer Research Center, Seattle, WA (United States); Fan, Wenhong [Fred Hutchinson Cancer Research Center, Seattle, WA (United States); Zhao Lueping [Fred Hutchinson Cancer Research Center, Seattle, WA (United States); Eaton, David L. [Departmental of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA (United States); Fred Hutchinson Cancer Research Center, Seattle, WA (United States); Zarbl, Helmut [Departmental of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA (United States) and Fred Hutchinson Cancer Research Center, Seattle, WA (United States)]. E-mail: hzarbl@fhcrc.org

    2006-01-29

    Aflatoxin B1 (AFB{sub 1}) is a potent human hepatotoxin and hepatocarcinogen produced by the mold Aspergillus flavus. In human, AFB{sub 1} is bioactivated by cytochrome P450 (CYP450) enzymes, primarily CYP1A2, to the genotoxic epoxide that forms N{sup 7}-guanine DNA adducts. To characterize the transcriptional responses to genotoxic insults from AFB{sub 1}, a strain of Saccharomyces cerevisiae engineered to express human CYP1A2 was exposed to doses of AFB{sub 1} that resulted in minimal lethality, but substantial genotoxicity. Flow cytometric analysis demonstrated a dose and time dependent S phase delay under the same treatment conditions, indicating a checkpoint response to DNA damage. Replicate cDNA microarray analyses of AFB{sub 1} treated cells showed that about 200 genes were significantly affected by the exposure. The genes activated by AFB{sub 1}-treatment included RAD51, DUN1 and other members of the DNA damage response signature reported in a previous study with methylmethane sulfonate and ionizing radiation [A.P. Gasch, M. Huang, S. Metzner, D. Botstein, S.J. Elledge, P.O. Brown, Genomic expression responses to DNA-damaging agents and the regulatory role of the yeast ATR homolog Mec1p, Mol. Biol. Cell 12 (2001) 2987-3003]. However, unlike previous studies using highly cytotoxic doses, environmental stress response genes [A.P. Gasch, P.T. Spellman, C.M. Kao, O. Carmel-Harel, M.B. Eisen, G. Storz, D. Botstein, P.O. Brown, Genomic expression programs in the response of yeast cells to environmental changes, Mol. Biol. Cell 11 (2000) 4241-4257] were largely unaffected by our dosing regimen. About half of the transcripts affected are also known to be cell cycle regulated. The most strongly repressed transcripts were those encoding the histone genes and a group of genes that are cell cycle regulated and peak in M phase and early G1. These include most of the known daughter-specific genes. The rapid and coordinated repression of histones and M/G1-specific

  6. Structural and thermal stability criteria of Bi{sub 2}O{sub 3}-B{sub 2}O{sub 3} glasses

    Energy Technology Data Exchange (ETDEWEB)

    Shaaban, Essam R; Saddeek, Yasser B [Physics Department, Faculty of Science, Al-Azhar University, PO 71452, Assiut (Egypt); Shapaan, M [Physics Department, Faculty of Science, Al-Azhar University, Cairo, Nasr City (Egypt)], E-mail: esam_ramadan2005@yahoo.com

    2008-04-16

    Glasses with compositions xBi{sub 2}O{sub 3}-(100-x)B{sub 2}O{sub 3} with 30{<=}x{<=}60 mol% have been prepared using the normal melt quenching technique. Infrared (IR) spectroscopy was used as a structural probe of the nearest-neighbor environment in the glass network. Assessment of the thermal stability of these glasses was achieved in terms of various simple quantitative methods based on the characteristic temperatures, such as the glass transition temperature, T{sub g}, the onset temperature of crystallization, T{sub in}, the temperature corresponding to the maximum crystallization rate, T{sub p}, and the melting temperature, T{sub m}. In this case, k{sub gl} may be more suitable for estimating the glass thermal stability in the above composition range. In this work the kinetic parameter K{sub r}(T) is added to the stability criteria. The thermal stability of the glasses that were studied has been correlated with the activation energy of crystallization by this kinetic criterion and compared with those evaluated by other criteria. The results of both the criteria and the kinetic parameter K{sub r}(T) confirm that the thermal stability decreases with increasing Bi{sub 2}O{sub 3} content. The former parameters, besides the average force constant of the BO{sub 3} structural unit, were characterized and discussed in terms of the changes in the glass structure.

  7. High temperature x ray diffraction determination of the body-centered-cubic-face-centered-cubic transformation temperature in (Fe{sub 70}Ni{sub 30}){sub 88}Zr{sub 7}B{sub 4}Cu{sub 1} nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Ipus, J. J.; McHenry, M. E. [Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Herre, P. [Institute for Metallic Materials, IFW Dresden, Helmholtzstrasse 20, Dresden D-01069 (Germany); Ohodnicki, P. [National Energy Technology Laboratory, U.S. Department of Energy, Pittsburgh, Pennsylvania 15236 (United States)

    2012-04-01

    In situ high-temperature x ray diffraction and magnetization measurements were performed on a melt-spun (Fe{sub 70}Ni{sub 30}){sub 88}Zr{sub 7}B{sub 4}Cu{sub 1} amorphous alloy to follow its structural evolution. At 728 K, a bcc-FeNi phase was observed as the primary crystallization product followed by transformation to an fcc phase {approx}773 K. During cooling to room temperature, the fcc-to-bcc transformation was not observed, and the metastable fcc-NiFe phase was retained at room temperature.

  8. Preparation , rare earth doping and characterization of glasses and transparent glass-ceramics in the system Pb F{sub 2}-Cd F{sub 2}-M O (M O=Si O{sub 2}, B{sub 2} O{sub 3}, Te O{sub 2} and P{sub 2} O{sub 5})

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M.A.P.; Ribeiro, S.J.L.; Messaddeq, Y. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica; Briois, V. [Universit Paris-Sud, Orsay (France). LURE; Poulain, M. [Universite de Rennes (France). CEMA

    2000-07-01

    In this work, we presents general results on the preparation and characterization of some related glasses. Various well known glasses former oxides were used together with Pb F{sub 2}-Cd F{sub 2} towards the preparation of a new glasses. Results from thermal analysis, X-ray diffraction and absorption (Exafs) are presented for the Pb F{sub 2}-Cd F{sub 2}-M O systems, where M O=Si O{sub 2}, B{sub 2} O{sub 3}, Te O{sub 2} and P{sub 2} O{sub 5}. (author)

  9. Enhanced high-temperature cycling of Li{sub 2}O–2B{sub 2}O{sub 3}-coated spinel-structured LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} cathode material for application to lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Ji Su [Energy and Environmental Division, Korea Institute of Ceramic Engineering and Technology, 233-5 Gasan-dong, Geumcheon-gu, Seoul 153-801 (Korea, Republic of); Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Yoon, Seung-Beom [Department of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seodaemoon-gu, Seoul 120-749 (Korea, Republic of); Yoon, Won-Sub [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kang, Yong-Mook [Department of Chemistry, Dongguk University, Seoul 100-715 (Korea, Republic of); Park, Sun-Min [Energy and Environmental Division, Korea Institute of Ceramic Engineering and Technology, 233-5 Gasan-dong, Geumcheon-gu, Seoul 153-801 (Korea, Republic of); Lee, Jae-Won, E-mail: jwlee7@dankook.ac.kr [Department of Energy Engineering, Dankook University, San 29 Anseo-dong, Dongnam-gu, Cheonan-si, Chungnam 330-714 (Korea, Republic of); Roh, Kwang Chul, E-mail: rkc@kicet.re.kr [Energy and Environmental Division, Korea Institute of Ceramic Engineering and Technology, 233-5 Gasan-dong, Geumcheon-gu, Seoul 153-801 (Korea, Republic of)

    2014-07-15

    Highlights: • LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} (LNMO) coated with layer of Li{sub 2}O–2B{sub 2}O{sub 3} (LBO)–glass was synthesized. • The LBO coating layer effectively suppressed the growth of an organic CEI layer. • The LBO coated LNMO had stabilized the cell impedance during cycling. • These changes greatly enhance cyclic retention of LNMO at high temperature. - Abstract: A Li{sub 2}O–2B{sub 2}O{sub 3}–glass-coated LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} (LNMO) cathode active material (GC-LNMO) was synthesized to enhance the thermal stability of LNMO-based electrodes for lithium-ion batteries. The morphologies of the surface-coating layers were analyzed using transmission electron microscopy. The glass coating prevented the surface of the LNMO-based electrode from being directly exposed to the liquid electrolyte solution, preventing Mn at the electrode surface from dissolving into the electrolyte and thus preventing the cell impedance from increasing through the undesirable formation of a cathode–electrolyte-interphase layer and the development of facile charge transfer kinetics during cycling. The electrochemical performance measurements demonstrated that the GC-LNMO-based electrode exhibited remarkably enhanced electrochemical reversibly and stability at elevated temperature (60 °C)

  10. Uptake of radiolabeled morphiceptin and its analogs by experimental mammary adenocarcinoma: in vitro and in vivo studies

    Energy Technology Data Exchange (ETDEWEB)

    Mirowski, M. E-mail: mirowski@ich.pharm.am.lodz.pl; Wiercioch, R.; Janecka, A.; Balcerczak, E.; Byszewska, E.; Birnbaum, G.; Byzia, Sz.; Garnuszek, P.; Wierzbicki, R

    2004-05-01

    Morphiceptin (Tyr-Pro-Phe-Pro-NH{sub 2}) and its analogs modified at position 3: [D-Phe{sup 3}]morphiceptin, [D-ClPhe{sup 3}]morphiceptin and [D-Cl{sub 2}Phe{sup 3}]morphiceptin were synthesized and labeled with [{sup 125}I] or [{sup 131}I]. Their binding to membranes isolated from experimental adenocarcinoma was examined in vitro with the use of a cross-linking assay followed by the Western blot technique. The radioactive complex had molecular weight of about 65 kDa and was detectable by anti-{mu}-opioid receptor polyclonal antibody. Expression of the {mu}-opioid receptor in mouse mammary adenocarcinoma was confirmed by reverse transcriptase-polymerase chain reaction. The binding studies showed the highest affinity and capacity for [D-Phe{sup 3}]morphiceptin (K{sub d} 0.39 and B{sub max} 1112) and [D-ClPhe{sup 3}]morphiceptin (K{sub d} 1.8 and B{sub max} 220). Morphiceptin and its D-Cl{sub 2}Phe analog had significantly lower B{sub max} values (131 and 83, respectively). Biodistribution experiments in tumor-bearing C3H/Bi mice with the use of the {sup 131}I-labeled peptides confirmed the results of our in vitro studies. The highest accumulation of radioactive peptides in the tumor tissue was also found for peptides with D-Phe and D-ClPhe.

  11. Parametric study on uniplanar K-joints made of RHS regarding axial force, in-plane bending and out-of-plane bending moments

    Energy Technology Data Exchange (ETDEWEB)

    Mang, F.; Herion, S.; Bucak, O. [Univ. of Karlsruhe (Germany)

    1994-12-31

    This paper presents first results of calculations according to the finite element method for uniplanar K-joints with gap. The investigations cover thin-walled rectangular hollow sections of commonly used dimensions and manufacture. The employed finite element model has been optimized and checked carefully in a research program sponsored by the Deutsche Forschungsgemeinschaft DFG (Research foundation of German government) dealing with multiplanar K-joints with gap. Compared to previous investigations, the influence of axial load, in-plane bending moments (IPB) and out-of-plane bending moments (OPB) are considered separately. With these models, parametric studies have been carried out to make statements on the strain concentration factors SNCF in terms of the geometric parameters {beta} = b{sub 1}/b{sub 0}; {tau} = t{sub 1}/t{sub 0} and gap g. As far as possible, graphs are given.

  12. Measurement of internal tensile stress in Co{sub 68.2}Fe{sub 4.3}Cr{sub 3.5}Si{sub 13}B{sub 11} glass-coated amorphous microwires using the stress sensitivity of saturation magnetostriction

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Kaihuang, E-mail: lkh2020@163.com; Lu, Zhichao; Liu, Tiancheng; Li, Deren

    2013-08-15

    The internal tensile stresses in Co{sub 68.2}Fe{sub 4.3}Cr{sub 3.5}Si{sub 13}B{sub 11} glass-coated amorphous microwires are measured experimentally by using the stress sensitivity of saturation magnetostriction. The obtained results show that the internal tensile stress is 1420 MPa for microwire with metallic core diameter of 20.7 µm and glass cover thickness of 14.5 µm, while it decreases to 640 MPa after glass removal. The measured results agree well with the theoretical results calculated by Chiriac et al. - Highlights: • Internal stresses in amorphous microwires have been measured experimentally. • The stress sensitivity of saturation magnetostriction was adopted. • The results agree with the theoretical results calculated by Chiriac et al.

  13. New type of nido-carborane of platinum: a pseudocloso-carborane. X-ray structural investigation of (Ph/sub 3/P)/sub 2/Pt-6,9-C/sub 2/B/sub 8/H/sub 10/

    Energy Technology Data Exchange (ETDEWEB)

    Kukina, G.A.; Porai-Koshits, M.A.; Sergienko, V.S.

    1987-02-01

    The reaction of Na/sub 2/C/sub 2/B/sub 8/H/sub 10/ with Pt(PPh/sub 3/)/sub 2/Cl/sub 2/ gives the complex (Ph/sub 3/P)/sub 2/PtC/sub 2/B/sub 8/H/sub 10/. Its structure has been established by x-ray diffraction analysis /lambdaMo, 6139 reflections, combination of anisotropic and isotropic (C(Ph)) least-squares methods with inclusion of located H(carborane) and calculated H(Ph) atoms, R = 0.045/. The crystals are triclinic: a = 11.035, b = 11.420, c = 16.154 A, ..cap alpha.. = 90.97, ..beta.. = 92.89, ..gamma.. = 114.36/sup 0/, Z = 2, space group P anti 1. It has been shown that the metallocarborane part of the complex has the form of a decarborane basket with C atoms at opposing vertices (6,9) of the outer hexagonal frame and C-Pt-C bonds forming the handle of the basket. All the H atoms of the carborane are terminal, and there is one for each C and B atom. The coordination of the Pt atom is brought up to square coordination by the two P atoms of the phosphine groups. The bond lengths and angles are: Pt-P = 2.297 and 2.322, Pt-C = 2.141 and 2.154 A, PPtP = 93.72, CPtC = 94.8, PPtC = 84.0 and 87.7/sup 0/. The uniqueness of the pseudocloso-type structure found for carborane complexes of Pt and Pd has been noted.

  14. Bulk amorphous powder cores with low core loss by spark-plasma sintering Fe{sub 76}Si{sub 9.6}B{sub 8.4}P{sub 6} amorphous powder with small amounts of SiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xue [School of Material and Metallurgy, University of Science and Technology Liaoning (USTL), 185 Qianshan Zhong Road, Anshan, Liaoning 114051 (China); Lu, Gonghao, E-mail: ghlu@ustl.edu.cn [School of Chemical Engineering, University of Science and Technology Liaoning (USTL), 185 Qianshan Zhong Road, Anshan, Liaoning 114051 (China); Zhang, Zhiqiang [School of Chemical Engineering, University of Science and Technology Liaoning (USTL), 185 Qianshan Zhong Road, Anshan, Liaoning 114051 (China); Ju, Dongying [School of Material and Metallurgy, University of Science and Technology Liaoning (USTL), 185 Qianshan Zhong Road, Anshan, Liaoning 114051 (China); Makino, Akihiro [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2015-10-25

    Fe{sub 76}Si{sub 9.6}B{sub 8.4}P{sub 6} amorphous powder was produced by gas atomization. Next, bulk amorphous powder discs were prepared by pressing a mixture of Fe{sub 76}Si{sub 9.6}B{sub 8.4}P{sub 6} amorphous powder and a small amount of SiO{sub 2} powder using the spark plasma sintering technique. The resulting bulk amorphous powder cores were obtained from the compacted discs using an electrical spark erosion machine. The powder core with 5 mass% SiO{sub 2} shows both high saturation magnetization of 1.41 T and good soft magnetic properties, 23 A/m for coercive force and 117 for effective permeability at 1 kHz. The core also exhibits much lower core loss than silicon steels or the powder core without SiO{sub 2}, only 71 W/kg at a maximum magnetic induction of 0.2 T with a frequency of 10 kHz. The low core loss is due to a SiO{sub 2} insulator layer forming on the surface of the alloy powder that can effectively reduce the eddy current and consequently reduce the core loss. - Highlights: • An amorphous powder core is prepared by using spark-plasma sintering technique • The core shows good soft magnetic properties and much lower core loss. • The saturation magnetization is 1.41 T and the coercive force is 23 A/m. • The effective permeability at 1 kHz is 117. • The core loss at 10 kHz and maximum induction of 0.2 T is only 71 W/kg.

  15. Experimental study of high beta toroidal plasmas

    International Nuclear Information System (INIS)

    Experiments on the Wisconsin Levitated Toroidal Octupole have produced a wide range of stable high β plasmas with β significantly above single fluid MHD theory predictions. A stable β approx. 8% plasma, twice the fluid limit, is obtained with 5 rho/sub i/ approx. L/sub n/ and tau/sub β/ approx. = 6000 tau/sub Alfven/ = 600 μsec. The enhanced stability is explained with a kinetic treatment that includes the effect of finite ion gyroradius which couples the ballooning mode to an ion drift wave. In a more collisional, large gyroradius (2 rho/sub i/ approx. L/sub n/) regime, a stable β approx. 35% plasma is obtained with a decay time of 1000 Alfven times. Measurement of the equilibrium magnetic field in this regime indicates that the diamagnetic current density is five times smaller than predicted by ideal MHD, probably due to ion gyroviscosity. Particle transport is anomalous and ranges from agreement with the classical diffusion rate at the highest beta, lowest field plasma (B/sub P/ = 200 G), to thirteen times the classical rate in a β=11%, high field plasma (B/sub P/ = 860 G) where the level of enhancement increase with magnetic field. Fluctuations in density, electrostatic potential, and magnetic field have been studied in plasmas with β from 0.1% to 40%

  16. About LTCC materials in the substance system of CaO-La{sub 2}O{sub 3}-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}; Ueber LTCC-Werkstoffe aus dem Stoffsystem CaO-La{sub 2}O{sub 3}-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Gemeinert, Marion

    2009-09-01

    Glass ceramic composites made of glassy and crystalline powders offer numerous possibilities for modifying materials properties e.g. sintering behaviour, thermal expansion coefficient, mechanical behaviour, chemical durability, dielectric properties and surface quality for special use. Glass ceramic composite powders can be used for the production of ceramic green tapes which are processed by LTCC (Low Temperature Co-fired Ceramics)- technology to form ceramic multilayers for electronic packaging in microsystems. During free sintering of LTCC-multilayers a lateral shrinkage occurs which is connected with a comparatively high shrinkage tolerance. Different sintering technologies are used to avoid the lateral shrinkage. A new possibility to achieve a zero lateral shrinkage is given by use of a self-constrained laminate. Therefore a multilayer is produced of two different materials for inner and outer layers, showing different sintering temperatures ({delta}T>50 K). Object of this dissertation was the development of LTCC-materials, which can be used for inner layers of a self-constrained laminate to reduce the lateral shrinkage nearly to zero. Therefore LTCC-materials in the field of CaO-La{sub 2}O{sub 3}-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}, which can be sintered below 800 C, were investigated. Starting from the development of adapted glasses based on calcium lanthanium borate- and calcium lanthanium alumoborate glasses glass ceramic composites were produced by the addition of corundum powder. The composites crystallize during the sintering process almost completely. Lanthanum borate crystallizes from the glassy phase and calcium alumoborate and calcium alumoborate oxide respectively is formed by a chemical solid state reaction of the residual glassy phase, which is enriched by calcium borate, and the corundum. The proportional relation of the new crystalline phases determines the thermal and dielectric properties of the material. The most important formed new

  17. An experimental and ab initio study of the electronic spectrum of the jet-cooled F{sub 2}BO free radical

    Energy Technology Data Exchange (ETDEWEB)

    Grimminger, Robert; Clouthier, Dennis J., E-mail: dclaser@uky.edu [Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506-0055 (United States); Sheridan, Phillip M. [Department of Chemistry and Biochemistry, Canisius College, Buffalo, New York 14208 (United States)

    2014-04-28

    We have studied the B{sup ~} {sup 2}A{sub 1}–X{sup ~} {sup 2}B{sub 2} laser-induced fluorescence (LIF) spectrum of the jet-cooled F{sub 2}BO radical for the first time. The transition consists of a strong 0{sub 0}{sup 0} band at 446.5 nm and eight weak sequence bands to shorter wavelengths. Single vibronic level emission spectra obtained by laser excitation of individual levels of the B{sup ~} state exhibit two electronic transitions: a very weak, sparse B{sup ~}–X{sup ~} band system in the 450–500 nm region and a stronger, more extensive set of B{sup ~} {sup 2}A{sub 1}–A{sup ~} {sup 2}B{sub 1} bands in the 580–650 nm region. We have also performed a series of high level ab initio calculations to predict the electronic energies, molecular structures, vibrational frequencies, and rotational and spin-rotation constants in the X{sup ~} {sup 2}B{sub 2}, A{sup ~2}B{sub 1} and B{sup ~} {sup 2}A{sub 1} electronic states as an aid to the analysis of the experimental data. The theoretical results have been used as input for simulations of the rotationally resolved B{sup ~} {sup 2}A{sub 1}–X{sup ~} {sup 2}B{sub 2} 0{sub 0}{sup 0} LIF band and Franck-Condon profiles of the LIF and single vibronic level emission spectra. The agreement between the simulations obtained with purely ab initio parameters and the experimental spectra validates the geometries calculated for the ground and excited states and the conclusion that the radical has C{sub 2v} symmetry in the X{sup ~}, A{sup ~}, and B{sup ~} states. The spectra provide considerable new information about the vibrational energy levels of the X{sup ~} and A{sup ~} states, but very little for the B{sup ~} state, due to the very restrictive Franck-Condon factors in the LIF spectra.

  18. Alkali-metal/alkaline-earth-metal fluorine beryllium borate NaSr{sub 3}Be{sub 3}B{sub 3}O{sub 9}F{sub 4} with large nonlinear optical properties in the deep-ultraviolet region

    Energy Technology Data Exchange (ETDEWEB)

    Reshak, A. H., E-mail: maalidph@yahoo.com [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); Huang, Hongwei [School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Kamarudin, H. [Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia); Auluck, S. [Council of Scientific and Industrial Research—National Physical Laboratory, Dr. K S Krishnan Marg, New Delhi 110012, India and Physics Department, Indian Institute of Technology - Delhi, Hauz Khas, New Delhi 110016 (India)

    2015-02-28

    The linear optical response and second harmonic generation (SHG) in alkali-metal/alkaline-earth-metal fluorine beryllium borate NaSr{sub 3}Be{sub 3}B{sub 3}O{sub 9}F{sub 4} are investigated by means of density functional theory. Calculations are performed using four types of exchange correlations: Ceperley-Alder local density approximation, Perdew Burke and Ernzerhof general gradient approximation, Engel-Vosko generalized gradient approximation, and the recently modified Becke-Johnson potential (mBJ). The mBJ approach brings the calculated band gap (7.20 eV) in excellent agreement with the experimental one (7.28 eV). The calculated values of the uniaxial anisotropy δε=−0.076 and the birefringence Δn(0)=0.052 indicate considerable anisotropy in the linear optical properties, which makes it favorable for the second harmonic generation. The dominant component of the second harmonic generation is χ{sub 111}{sup (2)}(ω). The value of |χ{sub 111}{sup (2)}(ω)| is about 1.2 pm/V at λ = 1064 nm in agreement with previous calculations. To analyze the origin of the high SHG of NaSr{sub 3}Be{sub 3}B{sub 3}O{sub 9}F{sub 4} single crystals, we have correlated the features of |χ{sub 111}{sup (2)}(ω)| spectra with the features of ε{sub 2}(ω) spectra as a function of ω/2 and ω. From the calculated dominant component |χ{sub 111}{sup (2)}(ω)|, we find that the microscopic first hyperpolarizability, β{sub 111}, the vector components along the dipole moment direction is 0.5 × 10{sup −30} esu at static limit and 0.6 × 10{sup −30} esu at λ = 1064 nm.

  19. Critical behavior of resistivity in the pressure-induced first to second order transition in Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}B{sub 0.04}O{sub 3} (B = Co and Cr)

    Energy Technology Data Exchange (ETDEWEB)

    Thiyagarajan, R.; Esakki Muthu, S.; Kalai Selvan, G. [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu (India); Mahendiran, R. [Department of Physics, 2 Science Drive 3, Faculty of Science, National University of Singapore, Singapore 117551 (Singapore); Arumugam, S., E-mail: sarumugam1963@yahoo.com [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu (India)

    2015-01-05

    Highlights: • 1st order PMI–FMM transition at T{sub IM} Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}B{sub 0.04}O{sub 3} (B = Co and Cr) samples. • Crossover from 1st to 2nd order is observed by the application of P on both the samples. • Critical exponents’ are close to the 3D Heisenberg model for the Co doped sample. • Critical exponents’ are close to the Mean field model for the Cr doped sample. - Abstract: We have investigated the hydrostatic pressure (P) dependence of the resistivity on Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}B{sub 0.04}O{sub 3} (B = Co and Cr) polycrystals. At ambient pressure, the temperature dependence of resistivity [ρ(T)] of both the samples show a first order paramagnetic insulator–ferromagnetic metallic transition at T = T{sub IM}. The application of P on both the samples increases the T{sub IM}, reduces the resistivity, and suppresses the hysteresis width, indicating a crossover from first to second order transition. The critical pressure, where the first–second order crossover takes place, are 2.02 and 2.40 GPa for Co and Cr doped samples respectively. The critical property of both systems around second order transition is investigated using Fisher–Langer relation and Suezaki–Mori method. The estimated critical exponents are close to the three-dimensional Heisenberg model for the Co doped sample suggesting short range interaction, and the exponents for the Cr doped sample follow the mean field theory suggesting long range ferromagnetic order. Further, the application of P suppresses the high temperature resistivity by reducing high temperature polarons in the case of the Cr doped sample, but it does not happen for the Co doped sample. The application of P helps to examine the stability of polarons in the high temperature regime.

  20. NO sub 3 , the study of molecular properties and photodissociation by ab initio method, spectroscopy, and translational spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B.

    1990-10-01

    This report discusses the following topics: molecular structure of NO{sub 3} radical studied by laser induced fluorescence; photodissociation and fluorescence spectroscopy of NO{sub 3} in molecular beam; vertical electronic spectrum of NO{sub 3}:{sup 2}A{prime}{sub 2}, {sup 2}E{double prime}({sup 2}A{sub 2}{sup 2}B{sub 1}), and {sup 2}E{prime} states; and Ab initio study of the vibrational spectra of NO{sub 3}.

  1. Study of tau lepton decay into leptons and K{sup 0}{sub L}; Etude des desintegrations du lepton tau en leptons et en K{sup 0}{sub L}

    Energy Technology Data Exchange (ETDEWEB)

    Park, H.J.

    1995-03-21

    In this thesis the {tau} lepton is identified from its decay products and the decay rates into electrons, muons and final states containing K{sub L}{sup 0} (kaons neutral long-lived) are measured. A {tau}{tau} pair is produced in the LEP storage ring from the electron-positron annihilation to a Z{sup 0} boson, e{sup +}e{sup -} {yields} Z{sup 0} {yields} {tau}{sup +}{tau}{sup -}. Each {tau} then decays, {tau} {yields} {nu}{sub {tau}}X where in this thesis only the final states X = e anti{nu}{sub e}, {mu} anti {nu}{sub {mu}}, and {pi}/K({pi}{sup d}eg)K{sub L}{sup 0} are considered. About 62000 {tau}{tau} pairs have been detected by the ALEPH (a detector for LEP physics) period 1991-93 at a center-of-mass energy of about 91 GeV, around the Z{sup 0} boson mass. The total systematic error on the leptonic {tau} decay fractions is 2.9 per mill for B{sub e} and 2.6 per mill for B{sub {mu}}, dominated by Monte Carlo statistics (1.4 per mill), non-{tau} backgrounds (1.4 per mill) and {tau}{tau} selection uncertainty (1.2 per mill). Finally, the following branching ratios are obtained: B{sub e} = (17.79 {+-} 0.13)%, B{sub {mu}} = (17.31 {+-} 0.12)%. These measurements allow to test precisely the e-{mu}-{tau} universality in the charged weak current couplings (Wl anti{nu}{sub l}), g{mu}/g{sub e} = 1.0003 {+-} 0.0051, g{tau}/g{mu} = 0.9979 {+-} 0.0027(world av. {tau}{sub {tau}}) {+-} 0.0023(B{sub l}) {+-} 0.0004(m{tau}) where unity corresponds to perfect e-{mu} and {mu}-{tau} universalities. In addition, a hadronic {tau} final state containing a K{sub L}{sup 0} is studied, which nicely demonstrates the ALEPH capabilities of K{sub L}{sup 0} identification. (authors). 66 refs., 115 figs., 49 tabs.

  2. Particle temperature measurements in closed chamber detonations using thermoluminescence from Li{sub 2}B{sub 4}O{sub 7}:Ag,Cu, MgB{sub 4}O{sub 7}:Dy,Li and CaSO{sub 4}:Ce,Tb

    Energy Technology Data Exchange (ETDEWEB)

    Yukihara, E.G., E-mail: eduardo.yukihara@okstate.edu [Physics Department, Oklahoma State University, 145 Physical Sciences, Stillwater, OK 74078 (United States); Coleman, A.C.; Bastani, S.; Gustafson, T. [Physics Department, Oklahoma State University, 145 Physical Sciences, Stillwater, OK 74078 (United States); Talghader, J.J. [Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 (United States); Daniels, A.; Stamatis, D.; Lightstone, J. M; Milby, C.; Svingala, F.R. [Naval Surface Warfare Center, Indian Head Explosive Ordnance Disposal Technology Division (NSWC IHEODTD), Indian Head, MD 20640 (United States)

    2015-09-15

    The present work describes the procedures and results from the first temperature measurements in closed chamber detonations obtained using the thermoluminescence (TL) of particles specifically developed for temperature sensing. Li{sub 2}B{sub 4}O{sub 7}:Ag,Cu (LBO), MgB{sub 4}O{sub 7}:Dy,Li (MBO) and CaSO{sub 4}:Ce,Tb (CSO) were tested separately in a total of 12 independent detonations using a closed detonation chamber at the Naval Surface Warfare Center, Indian Head Explosive Ordnance Disposal Technology Division (NSWC IHEODTD). Detonations were carried out using two different explosives: a high temperature plastic bonded explosive (HPBX) and a low temperature plastic bonded explosive (LPBX). The LPBX and HPBX charges produced temperatures experienced by the TL particles to be between ~550–670 K and ~700–780 K, respectively, depending on the shot. The measured temperatures were reproducible and typically higher than the thermocouple temperatures. These tests demonstrate the survivability of the TL materials and the ability to obtain temperature estimates in realistic conditions, indicating that TL may represent a reliable way of estimating the temperature experienced by free-flowing particles inside an opaque post-detonation fireball. - Highlights: • TL materials were tested in closed chamber detonations. • Temperatures experienced by the particles were ~550–670 K and ~700–780 K. • TL temperatures were reproducible and higher than thermocouple measurements. • Tests demonstrate TL material survival and ability to obtain temperature estimates.

  3. Crystallization of 21.25Gd{sub 2}O{sub 3}-63.75MoO{sub 3}-15B{sub 2}O{sub 3} glass induced by femtosecond laser at the repetition rate of 250 kHz

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, M.J.; Han, Y.M. [Department of Physics, Shanghai University, 99 Shangda Road, Shanghai 200444 (China); Liu, L.P. [Hunan Biological and Electromechanical Polytechnic, Changsha 410126 (China); Zhou, P.; Du, Y.Y.; Guo, Q.T. [Department of Physics, Shanghai University, 99 Shangda Road, Shanghai 200444 (China); Ma, H.L., E-mail: mahl@staff.shu.edu.cn [Department of Physics, Shanghai University, 99 Shangda Road, Shanghai 200444 (China); Dai, Y. [Department of Physics, Shanghai University, 99 Shangda Road, Shanghai 200444 (China)

    2010-12-01

    We report the formation of {beta}'-Gd{sub 2}(MoO{sub 4}){sub 3} (GMO) crystal on the surface of the 21.25Gd{sub 2}O{sub 3}-63.75MoO{sub 3}-15B{sub 2}O{sub 3} glass, induced by 250 kHz, 800 nm femtosecond laser irradiation. The morphology of the modified region in the glass was clearly examined by scanning electron microscopy (SEM). By micro-Raman spectra, the laser-induced crystals were confirmed to be GMO phases and it is found that these crystals have a strong dependence on the number and power of the femtosecond laser pulses. When the irradiation laser power was 900 mW, not only the Raman peaks of GMO crystals but also some new peaks at 214 cm{sup -1}, 240 cm{sup -1}, 466 cm{sup -1}, 664 cm{sup -1} and 994 cm{sup -1}which belong to the MoO{sub 3} crystals were observed. The possible mechanisms are proposed to explain these phenomena.

  4. Near-infrared quantum cutting in RE{sup 3+}/Yb{sup 3+} (RE = Pr, Tb, and Tm): GeO{sub 2}-B{sub 2}O{sub 3}-ZnO-LaF{sub 3} glasses via downconversion

    Energy Technology Data Exchange (ETDEWEB)

    Lakshminarayana, G. [State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China)], E-mail: glnphysics@rediffmail.com; Qiu Jianrong [State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China)

    2009-07-29

    An efficient near-infrared (NIR) quantum cutting (QC) involving the emission of two near-infrared photons for each blue photon absorbed is realized in RE{sup 3+}/Yb{sup 3+} (RE = Pr, Tb, and Tm): GeO{sub 2}-B{sub 2}O{sub 3}-ZnO-LaF{sub 3} glasses. Upon excitation of Pr{sup 3+}, Tb{sup 3+}, and Tm{sup 3+} ions with visible photons at 482, 483, and 467 nm two near-infrared photons at 950-1100 nm (Yb{sup 3+}:{sup 2}F{sub 5/2} {yields} {sup 2}F{sub 7/2}) through an efficient cooperative energy transfer from Pr{sup 3+}, Tb{sup 3+}, and Tm{sup 3+} to Yb{sup 3+}, with an optimal quantum efficiency close to 200% has been demonstrated. The development of the near-infrared quantum cutting oxyfluoride glasses could open a route in achieving high efficiency silicon-based solar cells by means of downconversion in the visible part of the solar spectrum to {approx}1000 nm photons with a two fold increase in the photon number.

  5. ALD Produced B{sub 2}O{sub 3}, Al{sub 2}O{sub 3} and TiO{sub 2} Coatings on Gd{sub 2}O{sub 3} Burnable Poison Nanoparticles and Carbonaceous TRISO Coating Layers

    Energy Technology Data Exchange (ETDEWEB)

    Weimer, Alan

    2012-11-26

    This project will demonstrate the feasibility of using atomic layer deposition (ALD) to apply ultrathin neutron-absorbing, corrosion-resistant layers consisting of ceramics, metals, or combinations thereof, on particles for enhanced nuclear fuel pellets. Current pellet coating technology utilizes chemical vapor deposition (CVD) in a fluidized bed reactor to deposit thick, porous layers of C (or PyC) and SiC. These graphitic/carbide materials degrade over time owing to fission product bombardment, active oxidation, thermal management issues, and long-term irradiation effects. ALD can be used to deposit potential ceramic barrier materials of interest, including ZrO{sub 2}, Y{sub 2}O{sub 3}:ZrO{sub 2} (YSZ), Al{sub 2}O{sub 3}, and TiO{sub 2}, or neutron-absorbing materials, namely B (in BN or B{sub 2}O{sub 3}) and Gd (in Gd{sub 2}O{sub 3}). This project consists of a two-pronged approach to integrate ALD into the next-generation nuclear plant (NGNP) fuel pellet manufacturing process:

  6. SUMMARY OF 2010 DOE EM INTERNATIONAL PROGRAM STUDIES OF WASTE GLASS MELT RATE ENHANCEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.; Marra, J.

    2011-01-19

    A collaborative study has been established under the U.S. Department of Energy (DOE) Office of Environmental Management International Program between the Savannah River National Laboratory (SRNL) and the V. G. Khlopin Radium Institute (KRI) in St. Petersburg, Russia, to investigate potential improvements in melt rate via chemical additions to the glass frit. Researchers at KRI suggested a methodology for selecting frit additives based on empirical coefficients for optimization of glass melting available in the Russian literature. Using these coefficients, KRI identified B{sub 2}O{sub 3}, CuO, and MnO as frit additives that were likely to improve melt rate without having adverse effects on crystallization of the glass or its chemical durability. The results of the melt rate testing in the SMK melter showed that the slurry feed rate (used as a gauge of melt rate) could be significantly increased when MnO or CuO were added to Frit 550 with the SMR-2 sludge. The feed rates increased by about 27% when MnO was added to the frit and by about 26% when CuO was added to the frit, as compared to earlier results for Frit 550 alone. The impact of adding additional B{sub 2}O{sub 3} to the frit was minor when added with CuO. The additional B{sub 2}O{sub 3} showed a more significant, 39% improvement in melt rate when added with MnO. The additional B{sub 2}O{sub 3} also reduced the viscosity of the glasses during pouring. Samples of the glasses from the melt rate testing characterized at SRNL showed that there were no significant impacts on crystallization of the glasses. All of the glasses had very good chemical durability. Chemical composition measurements showed that the frit additives were present in concentrations below the targeted values in some of the glasses. Therefore, it is possible that higher concentrations of these additives may further improve melt rate, although the impacts of higher concentrations of these components on crystallization and durability would need to

  7. Excited state non-adiabatic dynamics of pyrrole: A time-resolved photoelectron spectroscopy and quantum dynamics study

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Guorong [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023 (China); Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Neville, Simon P.; Worth, Graham A., E-mail: g.a.worth@bham.ac.uk [School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Schalk, Oliver [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Department of Physics, AlbaNova University Center, Stockholm University, Roslagstullsbacken 21, 109 61 Stockholm (Sweden); Sekikawa, Taro [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Department of Applied Physics, Hokkaido University, Kita-13 Nishi-8, Kita-ku, Sapporo 060-8628 (Japan); Ashfold, Michael N. R. [School of Chemistry, University of Bristol, Bristol BS8 1TS (United Kingdom); Stolow, Albert, E-mail: astolow@uottawa.ca [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Departments of Chemistry and Physics, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5 (Canada)

    2015-02-21

    The dynamics of pyrrole excited at wavelengths in the range 242-217 nm are studied using a combination of time-resolved photoelectron spectroscopy and wavepacket propagations performed using the multi-configurational time-dependent Hartree method. Excitation close to the origin of pyrrole’s electronic spectrum, at 242 and 236 nm, is found to result in an ultrafast decay of the system from the ionization window on a single timescale of less than 20 fs. This behaviour is explained fully by assuming the system to be excited to the A{sub 2}(πσ{sup ∗}) state, in accord with previous experimental and theoretical studies. Excitation at shorter wavelengths has previously been assumed to result predominantly in population of the bright A{sub 1}(ππ{sup ∗}) and B{sub 2}(ππ{sup ∗}) states. We here present time-resolved photoelectron spectra at a pump wavelength of 217 nm alongside detailed quantum dynamics calculations that, together with a recent reinterpretation of pyrrole’s electronic spectrum [S. P. Neville and G. A. Worth, J. Chem. Phys. 140, 034317 (2014)], suggest that population of the B{sub 1}(πσ{sup ∗}) state (hitherto assumed to be optically dark) may occur directly when pyrrole is excited at energies in the near UV part of its electronic spectrum. The B{sub 1}(πσ{sup ∗}) state is found to decay on a timescale of less than 20 fs by both N-H dissociation and internal conversion to the A{sub 2}(πσ{sup ∗}) state.

  8. Plasma chemistry study of PLAD processes

    Energy Technology Data Exchange (ETDEWEB)

    Qin Shu; Brumfield, Kyle; Liu, Lequn Jennifer; Hu, Yongjun Jeff; McTeer, Allen; Hsu, Wei Hui; Wang Maoying [Nanya Technology Inc., Santa Clara, CA 95054 (United States); Micron Technology Inc., Boise, ID 83707 (United States)

    2012-11-06

    Plasma doping (PLAD) shows very different impurity profiles compared to the conventional beam-line-based ion implantations due to its non-mass separation property and plasma environment. There is no simulation for PLAD process so far due to a lack of a dopant profile model. Several factors determine impurity profiles of PLAD process. The most significant factors are: plasma chemistry and deposition/etching characteristics of multi-ion species plasmas. In this paper, we present plasma chemistry and deposition/etching characteristics of PLAD processes versus co-gas dilutions. Four dopant plasmas including B{sub 2}H{sub 6}, BF{sub 3}, AsH{sub 3}, and PH{sub 3}, and two non-dopant plasmas including CH{sub 4} and GeH{sub 4} are studied and demonstrated.

  9. Study of the influence of the temperature in the magnetic properties and in microstructure in the permanent magnets Pr-Fe-B-Nb-Co based obtained by hydrogen; Estudo da influencia da temperatura nas propriedades magneticas e na microestrutura nos imas permanentes a base de Pr-Fe-B-Nb-Co obtidos com hidrogenio

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Suelanny Carvalho da

    2007-07-01

    Fine magnetic powders were produced using the hydrogenation disproportionation desorption and recombination (HDDR) process. The first stage in this work involved an investigation of the effect of the Co content and range of desorption/ recombination temperatures between 800 and 900 deg C with the purpose of optimizing the HDDR treatment for Pr{sub 14}Fe{sub 80}B{sub 6} and Pr{sub 14}Fe{sub bal}Co{sub x}B{sub 6}Nb{sub 0,1} (x= 0, 4, 8, 10, 12, 16) alloys. The cast alloys were annealed at 1100 deg C for 20 hours for homogenization. The processing temperature (desorption/ recombination) affected the microstructure and magnetic properties of the bonded magnets. The alloy with low cobalt content (4 at.%) required the highest reaction temperature (880 deg C) to yield anisotropic bonded magnets. The optimum temperature for alloys with 8 at.% Co and 10 at.% Co were 840 deg C and 820 deg C, respectively. Alloys with high cobalt content (12 at.% and 16 at.%) were processed at 840 deg C. The optimum desorption temperature for achieving high anisotropy for Pr{sub 14}Fe{sub 80}B{sub 6} and Pr{sub 14}Fe{sub 79,9}B{sub 6}Nb{sub 0,1} was 820 deg C. The best remanence (862 mT) was achieved with the Pr{sub 14}Fe{sub 67,9}B{sub 6}Co{sub 12}Nb{sub 0,1} magnet, processed at 840 deg C. Each alloy required an optimum reaction temperature and exhibited a particular microstructure according to the composition. The second stage of the work involved the characterization, for each temperature, of the Pr{sub 14}Fe{sub 80}B{sub 6} HDDR powder processed using X-ray diffraction analysis. The samples of the HDDR material were studied by synchrotron radiation powder diffraction using the Rietveld method for cell refinement, phase quantification and crystallite sizes determination. Scanning electron microscopy has also been employed to reveal the morphology of the HDDR powder. (author)

  10. Study of hyperfine interactions in intermetallic compounds Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In; Estudo de interacoes hiperfinas em compostos intermetalicos Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In e Ho(Ni,Pd)In

    Energy Technology Data Exchange (ETDEWEB)

    Lapolli, Andre Luis

    2006-07-01

    Systematic behavior of magnetic hyperfine field (B{sub hf}) in the intermetallic compounds Gd(Ni,Pd,Cu)In Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In was studied by Perturbed Gamma-Gamma Angular Correlation spectroscopy. The measurements of B{sub hf} were carried out at the rare earth atom and in sites using the nuclear probes {sup 140}Ce and {sup 11}'1Cd respectively. The variation of hyperfine field with temperature, in most cases, follows the Brillouin function predicted from the molecular field theory. The hyperfine field values at rare earth atom sites obtained from {sup 140}Ce probe as well as at in sites obtained from {sup 111}Cd probe for each series of compounds were extrapolated to zero Kelvin B{sub hf}(T=0) from these curves. These values were compared with the values of the literature for other compounds containing the same rare earth element and all of them show a linear relationship with the ordering temperature. This indicates that the main contribution to B{sub hf} comes from the conduction electron polarization (CEP) through Fermi contact interaction and the principal mechanism of magnetic interaction in these compounds can be described by the RKKY type interaction. The values of B{sub hf}(T=0) for each family of intermetallic compounds RNiIn and RPdIn when plotted as a function of 4f spin projection of rare earth element also shows a linear relationship. Exceptions are the results for the compounds RNiIn obtained with {sup 111}Cd probe where a small deviation from linearity is observed. The results of the measurements carried out with the {sup 111}Cd probe were also analyzed to obtain the hyperfine parameters of the quadrupole interaction as a function of temperature for RPdln and GdNiIn compounds. The results show that for the compound GdPdIn there might be some Gd-In disorder at high temperature. (author)

  11. Probing the structures of neutral boron clusters using infrared/vacuum ultraviolet two color ionization: B[sub 11], B[sub 16], and B[sub 17

    NARCIS (Netherlands)

    Romanescu, C.; Harding, D. J.; Fielicke, A.; Wang, L. S.

    2012-01-01

    The structures of neutral boron clusters, B11, B16, and B17, have been investigated using vibrational spectroscopy and ab initio calculations. Infrared absorption spectra in the wavelength range of 650 to 1550 cm−1 are obtained for the three neutral boron clusters from the enhancement of their near-

  12. Atomic site preferences and its effect on magnetic structure in the intermetallic borides M{sub 2}Fe(Ru{sub 0.8}T{sub 0.2}){sub 5}B{sub 2} (M=Sc, Ti, Zr; T=Ru, Rh, Ir)

    Energy Technology Data Exchange (ETDEWEB)

    Brgoch, Jakoah, E-mail: jrbrgoc@gmail.com [Department of Chemistry, Iowa State University, Ames, IA 50011 (United States); Mahmoud, Yassir A. [Department of Chemistry, Iowa State University, Ames, IA 50011 (United States); Miller, Gordon J., E-mail: gmiller@iastate.edu [Department of Chemistry, Iowa State University, Ames, IA 50011 (United States)

    2012-12-15

    The site preference for a class of intermetallic borides following the general formula M{sub 2}Fe(Ru{sub 0.8}T{sub 0.2}){sub 5}B{sub 2} (M=Sc, Ti, Zr; T=Ru, Rh, Ir), has been explored using ab initio and semi-empirical electronic structure calculations. This intermetallic boride series contains two potential sites, the Wyckoff 2c and 8j sites, for Rh or Ir to replace Ru atoms. Since the 8j site is a nearest neighbor to the magnetically active Fe atom, whereas the 2c site is a next nearest neighbor, the substitution pattern should play an important role in the magnetic structure of these compounds. The substitution preference is analyzed based on the site energy and bond energy terms, both of which arise from a tight-binding evaluation of the electronic band energy, and are known to influence the locations of atoms in extended solids. According to these calculations, the valence electron-rich Rh and Ir atoms prefer to occupy the 8j site, a result also corroborated by experimental evidence. Additionally, substitution of Rh or Ir at the 8j site results in a modification of the magnetic structure that ultimately results in larger local magnetic moment on the Fe atoms. - Graphical abstract: The site preference for electron rich atoms to occupy the 8j (gray) site is identified in these intermetallic borides, while the magnetic structure is modified as a function of the substituted atoms band center. Highlights: Black-Right-Pointing-Pointer We identify the energetics dictating the site preference in a series of intermetallic borides. Black-Right-Pointing-Pointer Establish substitution rules for use in future directed synthetic preparations. Black-Right-Pointing-Pointer Identified changes in magnetic structure that accompany the site preference.

  13. Microstructural study of the crystallization of amorphous Fe–Sn–B ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Maťko, Igor, E-mail: igor.matko@savba.sk [Institute of Physics, Slovak Academy of Sciences, Dúbravska cesta 9, 845 11 Bratislava (Slovakia); Illeková, Emília; Peter Švec Sr; Švec, Peter; Janičkovič, Dušan [Institute of Physics, Slovak Academy of Sciences, Dúbravska cesta 9, 845 11 Bratislava (Slovakia); Vodárek, Vlastimil [VŠB-Technical University of Ostrava, Department of Materials Engineering, 708 33 Ostrava-Poruba (Czech Republic)

    2014-12-05

    Highlights: • Amorphous Fe{sub 78}Sn{sub 5}B{sub 17} ribbons were prepared by planar flow casting. • Crystallization was studied by thermal analysis, XRD and TEM. • The crystallization begins by formation of specific nanocrystalline Fe(Sn) phase. • Role of Sn in formation of the nanocrystalline phase is discussed. • Next step of the crystallization corresponding to complex process is also analysed. - Abstract: Amorphous Fe{sub 78}Sn{sub 5}B{sub 17} ribbons were prepared by planar flow casting. The thermodynamic stability and the kinetics of observed phase transformations were monitored by thermal analysis. The structure and morphology of phases forming upon the thermally activated crystallization is studied by X-ray diffraction and transmission electron microscopy. The crystallization begins by nucleation-and-growth of specific nanocrystalline bcc-Fe(Sn) phase, its structure is explored more in details and the role of Sn in its formation is discussed. In the next step of the crystallization a transformation of remaining amorphous matrix to iron borides runs via rather complex process, which is inspected more in details as well.

  14. Magnetostrictive behaviour of Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3-x}Mo{sub x}Cu{sub 1} alloys

    Energy Technology Data Exchange (ETDEWEB)

    Silveyra, J.M. [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, UBA-CONICET, Paseo Colon 850, C1063ACV Buenos Aires (Argentina); Cremaschi, V.J., E-mail: vcremas@gmail.co [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, UBA-CONICET, Paseo Colon 850, C1063ACV Buenos Aires (Argentina); Member of Carrera del Investigador, CONICET (Argentina); Vlasak, G.; Illekova, E.; Janickovic, D.; Svec, P. [Institute of Physics, Slovak Academy of Sciences, Dubravska cesta 9, 845 11 Bratislava (Slovakia)

    2010-08-15

    Magnetostriction, dilatation and calorimetric measurements were performed on FINEMET type as-quenched and heat treated ribbons. Nb was gradually replaced by Mo in order to study the influence of the refractory elements exchange on several magnetostriction parameters. The results could be correlated with magnetic and structural transformations throughout thermal treatments and assured that the whole series is suitable for technical applications.

  15. Uranyl complexes formed with a para-t-butylcalix[4]arene bearing phosphinoyl pendant arms on the lower rim. Solid and solution studies

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, F. de M. [Instituto Nacional de Investigaciones Nucleares, La Marquesa, Ocoyoacac (Mexico). Dept. de Quimica; Varbanov, S. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. of Organic Chemistry with Center of Phytochemistry; Buenzli, J.C.G. [Ecole Polytechnique Federale de Lausanne (EPFL) (Switzerland). Inst. of Chemical Sciences and Engineering; Rivas-Silva, J.F.; Ocana-Bribiesca, M.A. [Instituto de Fisica de la BUAP, Puebla (Mexico); Cortes-Jacome, M.A.; Toledo-Antonio, J.A. [Instituto Mexicano del Petroleo/Programa de Ingenieria Molecular (Mexico)

    2012-07-01

    The current interest in functionalized calixarenes with phosphorylated pendant arms resides in their coordination ability towards f elements and capability towards actinide/rare earth separation. Uranyl cation forms 1:1 and 1:2 (M:L) complexes with a tetra-phosphinoylated p-tert-butylcalix[4]arene, B{sub 4}bL{sup 4}: UO{sub 2}(NO{sub 3}){sub 2}(B{sub 4}bL{sup 4}){sub n} . xH{sub 2}O (n = 1, x = 2, 1; n = 2, x = 6, 2). Spectroscopic data point to the inner coordination sphere of 1 containing one monodentate nitrate anion, one water molecule and the four phosphinoylated arms bound to UO{sub 2}{sup 2+} while in 2, uranyl is only coordinated to calixarene ligands. In both cases the U(VI) ion is 8-coordinate. Uranyl complexes display enhanced metal-centred luminescence due to energy transfer from the calixarene ligands; the luminescence decays are bi-exponential with associated lifetimes in the ranges 220 {mu}s < {tau}{sub s} < 250 {mu}s and 630 {mu}s < {tau}{sub L} < 640 {mu}s, pointing to the presence of two species with differently coordinated calixarene, as substantiated by a XPS study of U(4f{sub 5/2,7/2}), O(1s) and P(2p) levels on solid state samples. The extraction study of UO{sub 2}{sup 2+} cation and trivalent rare-earth (Y, La, Eu) ions from acidic nitrate media by B{sub 4}bL{sup 4} in chloroform shows the uranyl cation being much more extracted than rare earths. (orig.)

  16. NMR STUDIES OF LIQUID CRYSTALS AND MOLECULES DISSOLVED IN LIQUID CRYSTAL SOLVENTS

    Energy Technology Data Exchange (ETDEWEB)

    Drobny, G.P.

    1982-11-01

    This thesis describes several studies in which nuclear magnetic resonance (nmr) spectroscopy has been used to probe the structure, orientation and dynamics of liquid crystal mesogens and molecules dissolved in liquid crystalline phases. In addition, a modern high field nmr spectrometer is described which has been used to perform such nmr studies. Chapter 1 introduces the quantum mechanical formalisms used throughout this thesis and briefly reviews the fundamentals of nuclear spin physics and pulsed nmr spectroscopy. First the density operator is described and a specific form for the canonical ensemble is derived. Then Clebsch-Gordon coefficients, Wigner rotation matrices, and irreducible tensor operators are reviewed. An expression for the equilibrium (Curie) magnetization is obtained and the linear response of a spin system to a strong pulsed r.f. irradiation is described. Finally, the spin interaction Hamiltonians relevant to this work are reviewed together with their truncated forms. Chapter 2 is a deuterium magnetic resonance study of two 'nom' liquid crystals which possess several low temperature mesomorphic phases. Specifically, deuterium quadrupolar echo spectroscopy is used to determine the orientation of the liquid crystal molecules in smectic phases, the changes in molecular orientation and motion that occur at smectic-smectic phase transitions, and the order of the phase transitions. For both compounds, the phase sequence is determined to be isotropic, nematic, smectic A, smectic C, smectic B{sub A}, smectic B{sub C}, and crystalline. The structure of the smectic A phase is found to be consistent with the well-known model of a two dimensional liquid in which molecules are rapidly rotating about their long axes and oriented at right angles to the plane of the layers. Molecules in the smectic C phase are found to have their long axes tilted with respect to the layer normal, and the tilt angle is temperature dependent, increasing from zero at the

  17. Moessbauer study of nanocrystalline PrFeB and PrFeCrB alloys

    Energy Technology Data Exchange (ETDEWEB)

    Barra-Barrera, A.D.; Murakami, R.K.; Partiti, C.S.M.; Villas-Boas, V. E-mail: val@macbeth.if.usp.br

    2001-05-01

    Ribbons of Pr{sub 4.5}Fe{sub 77}B{sub 18.5} and Pr{sub 5}Fe{sub 74}Cr{sub 3}B{sub 18} alloys were produced by melt spinning and then annealed by flash or conventional annealing to develop enhanced-remanence nanocrystalline magnetic material. These materials were studied by magnetic measurements, X-ray diffraction and Moessbauer spectroscopy in order to understand the relationship between structural and magnetic properties. These analyses showed that the phases present in these materials are Pr{sub 2}Fe{sub 14}B, Fe{sub 3}B and {alpha}-Fe. The samples with Cr present a coercive field 50% higher than the Cr-free samples. The Moessbauer spectra were analyzed as a superposition of the well-known spectra of Pr{sub 2}Fe{sub 14}B, Fe{sub 3}B and {alpha}-Fe. The mean hyperfine magnetic field of each phase was obtained from the spectral analysis, as well as, the relative amount of each phase present. From Moessbauer results it seems that Cr atoms preferentially dissolves in the Fe{sub 3}B phase.

  18. Relating B_S Mixing and B_S to mu+mu- with New Physics

    Energy Technology Data Exchange (ETDEWEB)

    Golowich, Eugene; /Massachusetts U., Amherst; Hewett, JoAnne; /SLAC; Pakvasa, Sandip; /Hawaii U.; Petrov, Alexey A; /Wayne State U. /Michigan U., MCTP; Yeghiyan, Gagik K; /Wayne State U.

    2012-06-11

    We perform a study of the standard model fit to the mixing quantities {Delta}M{sub B{sub s}}, and {Delta}{Lambda}{sub B{sub s}}/{Delta}M{sub B{sub s}} in order to bound contributions of new physics (NP) to B{sub s} mixing. We then use this to explore the branching fraction of B{sub s} {yields} {mu}{sup +}{mu}{sup -} in certain models of NP. In most cases, this constrains NP amplitudes for B{sub s} {yields} {mu}{sup +}{mu}{sup -} to lie below the standard model component.

  19. Radiation environment simulations at the Tevatron, studies of the beam profile and measurement of the Bc meson mass

    Energy Technology Data Exchange (ETDEWEB)

    Nicolas, Ludovic Y.

    2005-09-01

    The description of a computer simulation of the CDF detector at Fermilab and the adjacent accelerator parts is detailed, with MARS calculations of the radiation background in various elements of the model due to the collision of beams and machine-related losses. Three components of beam halo formation are simulated for the determination of the principal source of radiation background in CDF due to beam losses. The effect of a collimator as a protection for the detector is studied. The simulation results are compared with data taken by a CDF group. Studies of a 150 GeV Tevatron proton beam are performed to investigate the transverse diffusion growth and distribution. A technique of collimator scan is used to scrape the beam under various experimental conditions, and computer programs are written for the beam reconstruction. An average beam halo growth speed is given and the potential of beam tail reconstruction using the collimator scan is evaluated. A particle physics analysis is conducted in order to detect the B{sub c} {yields} J/{psi}{pi} decay signal with the CDF Run II detector in 360 pb{sup -1} of data. The cut variables and an optimization method to determine their values are presented along with a criterion for the detection threshold of the signal. The mass of the B{sub c} meson is measured with an evaluation of the significance of the signal.

  20. Study of the influence of zirconium and gallium on the magnetic properties and microstructures of praseodymium-based permanent magnets; Estudo da influencia do zirconio e galio nas propriedades magneticas e na microestrutura dos imas permanentes a base de praseodimio

    Energy Technology Data Exchange (ETDEWEB)

    Fusco, Alexandre Giardini

    2006-07-01

    In this work was studied the influence of the addition of 0.5 at. % of zirconium and gallium on praseodymium-based HD sintered magnets obtained using a mixture of alloys. The alloys used in this study were: Pr{sub 12.6}Fe{sub 68.3}Co{sub 11.6}B{sub 6}Zr{sub 0.5}Ga{sub 1}, Pr{sub 16}Fe{sub 75.5}B{sub 8}Zr{sub 0.5}, Pr{sub 13}Fe{sub 80.5}B{sub 6}Zr{sub 0.5}. The investigation started by measuring the magnetic properties and observing the microstructure of the magnets. After that, the magnets were annealed at 1000 deg C for 2 hours followed by rapid cooling, in a total of 10 hours. This heat treatment was followed by 5 hours at the same temperature up to a total of 35 hours. Changes in the microstructure were compared to the change in the magnetic properties aiming at a proper understanding of the role of each added element in relation to the magnetically hard phase (phase {phi}). It has been shown that gallium and zirconium act as grain refiners of the matrix phase {phi}. Gallium acts in the grain and favoring of the shape stability and improvement of the magnetic properties. For the Pr{sub 14.3}Fe{sub 71.9}Co{sub 5.8}B{sub 7}Zr{sub 0.5}Ga{sub 0.5} sintered magnet the evolution of the magnetic properties after 15 hours heat treatment was: remanence from (1.25{+-}0.02) T to (1.30{+-}0.02) T, intrinsic coercivity from (1.11{+-}0.02) T to (0.87{+-}0.02) T, squareness factor from (0.68{+-}0.02) to (0.82{+-}0.02) and energy product from (285{+-}5) kJ/m{sup 3} to (317{+-}5) kJ/m{sup 3}. Zirconium has two effects on the sintered magnets. Firstly, avoiding random grain growth and enhancing anisotropy. However, by concentrating on the grain boundaries, yield reverse domains and is detrimental to the intrinsic coercivity. For the sintered Pr{sub 14.5}Fe{sub 78}B{sub 7}Zr{sub 0.5} magnet the evolution of the magnetic properties achieved after a heat treatment of 15 hours was: remanence from (1.19{+-}0.02) T to (1.25{+-}0.02) T, coercivity from (0.74{+-}0.02) T to (0

  1. Structural and magnetic study of Mo-doped FINEMET

    Energy Technology Data Exchange (ETDEWEB)

    Silveyra, J.M., E-mail: jsilveyra@fi.uba.a [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires-CONICET, Paseo Colon 850, (C1063ACV) Buenos Aires (Argentina); Cremaschi, V.J. [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires-CONICET, Paseo Colon 850, (C1063ACV) Buenos Aires (Argentina); Miembro de la Carrera del Investigador del CONICET (Argentina); Janickovic, D.; Svec, P. [Institute of Physics, Slovak Academy of Sciences, Dubravska cesta 9, 845 11 Bratislava (Slovakia); Arcondo, B. [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires-CONICET, Paseo Colon 850, (C1063ACV) Buenos Aires (Argentina)

    2011-02-15

    In this paper, a study of the structural and the magnetic correlation of the crystalline and amorphous phases in the nanocrystalline system Fe{sub 73.5}Si{sub 13.5}B{sub 9}Nb{sub 3-x}Mo{sub x}Cu{sub 1} (x=0, 1.5, 2, 3) was made. By means of Moessbauer spectroscopy, simple mass balance considerations and density measurements, both phases fractions and chemical compositions were calculated (in at%, wt% and vol%). Then, quasistatic magnetic measurements and ab initio calculations were used in a magnetic balance model in order to estimate the magnetic contribution of the remaining amorphous phase, which was compared to that of as-quenched amorphous samples of the same composition. The difference in both magnitudes showed the influence of penetrating fields and that these became more important for higher crystalline fractions.

  2. New structural studies of liquid crystal by reflectivity and resonant X-ray diffraction; Nouvelles etudes structurales de cristaux liquides par reflectivite et diffraction resonante des rayons X

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, P

    2007-04-15

    This memory presents three structural studies of smectic Liquid Crystals by reflectivity and resonant diffraction of X-rays. It is divided in five chapters. In the first a short introduction to Liquid Crystals is given. In particular, the smectic phases that are the object of this study are presented. The second chapter is consecrated to the X-ray experimental techniques that were used in this work. The three last chapters present the works on which this thesis can be divided. Chapter three demonstrates on free-standing films of MHPOBC (historic liquid crystal that possesses the antiferroelectric sub-phases) the possibility to extend the technique of resonant X-ray diffraction to liquid crystals without resonant element. In the fourth chapter the structure of the B{sub 2} liquid crystal phase of bent-core molecules (or banana molecules) is elucidated by using resonant X-ray diffraction combined with polarization analysis of the diffracted beam. A model of the polarization of the resonant beam diffracted by four different structures proposed for the B{sub 2} phase is developed in this chapter. In the fifth chapter a smectic binary mixture presenting a very original critical point of phase separation is studied by X-ray reflectivity and optical microscopy. A concentration gradient in the direction perpendicular to the plane of the film seems to be induced by the free-standing film geometry. The results of a simplified model of the system are compatible with this interpretation.

  3. Study and optimization of boronization in Alcator C-Mod using the Surface Science Station (S{sup 3})

    Energy Technology Data Exchange (ETDEWEB)

    Ochoukov, Roman, E-mail: ochoukov@psfc.mit.edu [Plasma Science and Fusion Center MIT, NW17, 175 Albany Street, Cambridge, MA 02139 (United States); Whyte, Dennis; Lipschultz, Bruce; LaBombard, Brian [Plasma Science and Fusion Center MIT, NW17, 175 Albany Street, Cambridge, MA 02139 (United States); Gierse, Niels [Institute of Energy and Climate Research - Plasma Physics, Forschungszentrum Juelich GmbH, Association EURATOM-FZJ, Partner in the Trilateral Euregio Cluster, Juelich (Germany); Physikalisches Institut, Universitaet zu Koeln, D-50937 Cologne (Germany); Harrison, Soren [Fusion Research Technologies, 519 Somerville Avenue 243, Somerville, MA 02143 (United States)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer Boron deposition profiles measured on Alcator C-Mod during boronization. Black-Right-Pointing-Pointer Boron deposition profile is consistent with ionic deposition. Black-Right-Pointing-Pointer Monte Carlo simulation of boron deposition agrees with experiment assuming warm ({approx}1-10 eV) boron{sup +1} ions. - Abstract: A Surface Science Station (S{sup 3}) on the Alcator C-Mod tokamak is used to study and optimize the location and rate of boron film deposition in situ during electron cyclotron (EC) discharge plasmas using 2.45 GHz radio-frequency (RF) heating and a mixture of helium and diborane (B{sub 2}D{sub 6}) gasses. The radial profile of boron deposition is measured with a pair of quartz microbalances (QMB) on S{sup 3}, the faces of which can be rotated 360 Degree-Sign including orientations parallel and perpendicular to the toroidal magnetic field B{sub T} {approx}0.1 T. The plasma electron density is measured with a Langmuir probe, also on S{sup 3} in the vicinity of the QMBs, and typical values are {approx}1 Multiplication-Sign 10{sup 16} m{sup -3}. A maximum boron deposition rate of 0.82 {mu}g/cm{sup 2}/min is obtained, which corresponds to 3.5 nm/min if the film density is that of solid boron. These deposition rates are sufficient for boron film applications between tokamak discharges. However the deposition does not peak at the EC resonance as previously assumed. Rather, deposition peaks near the upper hybrid (UH) resonance, {approx}5 cm outboard of the EC resonance. This has implications for RF absorption, with the RF waves being no longer damped on the electrons at the EC resonance. The previously inferred radial locations of critical erosion zones in Alcator C-Mod also need to be re-evaluated. The boron deposition profile versus major radius follows the ion flux/density profile, implying that the boron deposition is primarily ionic. The application of a vertical magnetic field (B{sub V} {approx}0.01 T) was

  4. A study of B(s)0 to J/psi phi in the D0 experiment and an example of HEP technology transfer

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Daniela Ursula

    2002-01-01

    After years of preparation, data taking with the upgraded D0 detector at the Tevatron proton-antiproton collider has begun. The large amount of data produced in a p{bar p}-collider requires sophisticated triggers to filter out the interesting events. Described in this thesis is the development of trigger software for the newly implemented Silicon Microstrip Tracker. D0 is a multi-purpose detector with a broad physics program. one area being studied at D0 is B mesons. An algorithm for reconstructing the B{sub s}{sup 0} and B{sub d}{sup 0} mesons and for measuring their lifetimes has been developed and is described in this thesis. The results suggest that an improvement of the current lifetime measurements can be achieved within the next two years. The reconstruction of a J/{psi} meson forms the basis for a wide range of b-physics. Data taken with the muon system during the commissioning period of the detector has been analyzed and a signal for the J/{psi} meson has been found. Systematic transfer of HEP technologies into other areas and their commercial exploitation plays an important role in the future of particle physics. An area of particular interest is DNA sequencing as shown by the recent completion of the sequencing of the human genome. The final part of this thesis details the development of a simulation for a high throughput sequencing device which is currently being developed at Imperial College.

  5. Communication: A vibrational study of propargyl cation using the vacuum ultraviolet laser velocity-map imaging photoelectron method

    Energy Technology Data Exchange (ETDEWEB)

    Gao Hong; Lu Zhou; Yang Lei; Zhou Jingang; Ng, C. Y. [Department of Chemistry, University of California, Davis, California 95616 (United States)

    2012-10-28

    By employing the vacuum ultraviolet (VUV) laser velocity-map imaging photoelectron (VUV-VMI-PE) method, we have obtained a vibrationally resolved photoelectron spectrum of gaseous propargyl radical [C{sub 3}H{sub 3}(X{sup 2}B{sub 1})] in the energy range of 0-4600 cm{sup -1} above its ionization energy. The cold C{sub 3}H{sub 3} radicals were produced from a supersonically cooled radical beam source based on 193 nm ArF photodissociation of C{sub 3}H{sub 3}Cl. The VUV-VMI-PE spectrum of C{sub 3}H{sub 3} thus obtained reveals a Franck-Condon factor (FCF) pattern with a highly dominant origin band along with weak vibrational progressions associated with excitations of the C-C {nu}{sub 5}{sup +}(a{sub 1}) and C{identical_to}C {nu}{sub 3}{sup +}(a{sub 1}) symmetric stretching modes and the CCH {nu}{sub 7}{sup +}(b{sub 1}) out-of-plane bending mode of C{sub 3}H{sub 3}{sup +}(X{sup 1}A{sub 1}). The {nu}{sub 5}{sup +}(a{sub 1}) vibrational frequency of 1120 cm{sup -1} determined in the present study is lower than the value deduced from the recent Ar-tagged infrared photodissociation study by 102 cm{sup -1}, confirming the highly accurate vibrational frequency predictions obtained by the most recent state-of-the-art ab initio quantum calculations. The observation of the FCF disallowed {nu}{sub 7}{sup +}(b{sub 1}) mode is indicative of vibronic interactions. The discrepancy observed between the FCF pattern determined in the present study and that predicted by a recent high-level quantum theoretical investigation can be taken as evidence that the potential energy surfaces used in the latter theoretical study are in need of improvement in order to provide a reliable FCF prediction for the C{sub 3}H{sub 3}/C{sub 3}H{sub 3}{sup +} photoionization system.

  6. Reliability design and case study of a refrigerator compressor subjected to repetitive loads

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Seong-woo [SAMSUNG Electronics Co., Ltd., 272, Refrigeration Division, Oseon-Dong, Gwangsan-Gu, Gwangju-City, Korea 506-723 (Korea); Pecht, Michael [CALCE Electronic Packaging Research Center, University of Maryland, College Park, Maryland, TX 77843-3123 (United States); O' Neal, Dennis L. [Department of Mechanical Engineering, Texas A and M University, College Station, TX (United States)

    2009-05-15

    A newly designed crankshaft of a compressor for a side-by-side (SBS) refrigerator was studied. Using mass and energy conservation balances, a variety of compressor loads typically found in a refrigeration cycle were analyzed. The laboratory failure modes and mechanisms were compressor locking and crankshaft wear. These were similar to those of the failed samples in the field. Failure analysis, accelerated life testing (ALT), and corrective actions were used to identify the key reliability parameters. The design parameters of the crankshaft included the hole locations and the groove of the crankshaft used for oil lubrication, crankshaft hardness, and thrust washer interference. Based on the analysis and design changes, the B{sub 1} life of the new design is now over ten years with a yearly failure rate of 0.01 percent. A five step procedure is recommended for parts design. (author)

  7. A study on the magnetic behavior of Nd-Fe-B/{alpha}-Fe nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    Madeswaran, S; Tokiwa, K [Polyscale Technology Research Center, Tokyo University of Science 2641 Yamazaki, Noda, Chiba 278-8510 (Japan); Tamano, S; Goto, S, E-mail: smades@rs.noda.tus.ac.j [Department of Applied Electronics, Tokyo University of Science, Japan 2641 Yamazaki, Noda, Chiba, 278-8510 (Japan)

    2010-06-01

    Nanocomposite Nd-Fe-B / {alpha}-Fe thin films were prepared by sputtering successively a Nd-rich Nd{sub 21}Fe{sub 64}B{sub 15} and a Fe targets in a multilayer structure using radio frequency (RF) magnetron gun. We have studied the influence of thickness of {alpha}-Fe layer on the magnetic properties of Nd-Fe-B / {alpha}-Fe thin films. A nanocomposite thin film with 15nm thick {alpha}-Fe layer prepared on 550{sup 0}C heated substrate gives the highest energy product, 190 kJ/m{sup 3} along with a coercivity of 950 kA/m. Magnetic hysteresis loop measurement shows that the hard (Nd-Fe-B) and soft ({alpha}-Fe) layers are exchange coupled firmly for the films deposited on heated substrate whereas the two layers are decoupled for room temperature deposited and post annealed films.

  8. First principles lattice dynamics study of SnO{sub 2} polymorphs

    Energy Technology Data Exchange (ETDEWEB)

    Erdem, I., E-mail: ierdem@pau.edu.tr [Department of Physics, Pamukkale University, Kinikli Campus, 20020 Denizli (Turkey); Kart, H.H. [Department of Physics, Pamukkale University, Kinikli Campus, 20020 Denizli (Turkey); Cagin, T. [Department of Material Science and Engineering, Texas A& M University, College Station, TX 77843-3003 (United States)

    2015-06-05

    Highlights: • Mode frequencies at the zone center (Γ) after LO/TO splitting are calculated. • Softening of B{sub 1g} mode at the rutile-CaCl{sub 2} phase transition is confirmed. • Dispersions of polymorphs of SnO{sub 2} are calculated for the first time except for rutile. • They show entire dynamical stability except for α-PbO{sub 2} phase. • Thermal properties are evaluated by applying quasi harmonic approximation. - Abstract: The structural properties of SnO{sub 2} polymorphs in the sequential order of observed phases in experiments are determined by the density functional theory (DFT) calculations based on local density approximation (LDA) of ultra soft pseudo potentials (US-PPs). Phonon dispersion relations are calculated by the lattice dynamics calculations. Shifts in the infrared (IR) active optical modes due to polarization (LO/TO splitting) are also calculated. Moreover, softening of B{sub 1g} mode at the rutile-CaCl{sub 2} second-order ferroelastic phase transition is confirmed. Thermal properties, such as temperature behavior of bulk modulus and thermal expansion in the rutile phase are obtained by employing quasiharmonic approximation (QHA). They are in good agreement with the available experimental results. Dynamic stabilities of SnO{sub 2} polymorphs except for the rutile phase are checked for the first time by using phonon dispersions. The rutile, CaCl{sub 2}, pyrite, ZrO{sub 2} and cotunnite type structures have shown thermodynamical stability. The cause of α-PbO{sub 2} phase showing nearly stability is discussed in the light of experimental studies. However, the fluorite type structure is definitely instable even at different pressures. It may not be one of SnO{sub 2} polymorphs.

  9. Rotationally resolved state-to-state photoelectron study of niobium carbide radical

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Zhihong; Huang, Huang; Zhang, Zheng; Chang, Yih-Chung; Ng, C. Y., E-mail: cyng@ucdavis.edu [Department of Chemistry, University of California, Davis, California 95616 (United States)

    2014-07-14

    By employing the two-color visible (VIS)-ultraviolet (UV) laser photoexcitation scheme and the pulsed field ionization-photoelectron (PFI-PE) detection, we have obtained rovibronically selected and resolved photoelectron spectra for niobium carbide cation (NbC{sup +}). The fully rotationally resolved state-to-state VIS-UV-PFI-PE spectra thus obtained allow the unambiguous assignments of rotational photoionization transitions, indicating that the electronic configuration and term symmetry of NbC{sup +}(X{sup ~}) ground state are …10σ{sup 2} 5π{sup 4} 11σ{sup 2} (X{sup ~1}Σ{sup +}). Furthermore, the rotational analysis of these spectra yields the ionization energy of NbC [IE(NbC)] to be 56 369.2 ± 0.8 cm{sup −1} (6.9889 ± 0.0001 eV) and the rotation constant B{sub 0}{sup +} = 0.5681 ± 0.0007 cm{sup −1}. The latter value allows the determination of the bond distance r{sub 0}{sup +} = 1.671 ± 0.001 Å for NbC{sup +}(X{sup ~1}Σ{sup +}). Based on conservation of energy, the IE(NbC) determined in the present study along with the known IE(Nb) gives the difference of 0 K bond dissociation energies (D{sub 0}’s) for NbC{sup +} and NbC, D{sub 0}(NbC{sup +}) − D{sub 0}(NbC) = −1855.4 ± 0.9 cm{sup −1} (−0.2300 ± 0.0001 eV). The energetic values and the B{sub 0}{sup +} constant determined in this work are valuable for benchmarking state-of-the-art ab initio quantum calculations of 4d transition metal-containing molecules.

  10. Study of a new glass matrix by the thermoluminescence technique; Estudo de uma nova matriz vitrea pela tecnica de termoluminescencia

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Pamela Z.; Vedovato, Uly P.; Cunha, Diego M. da; Dantas, Noelio O.; Silva, Anielle C.A.; Neves, Lucio P.; Perini, Ana P., E-mail: anapaula.perini@ufu.br [Universidade Federal de Uberlandia (INFIS/UFU), MG (Brazil). Instituto de Fisica; Caldas, Linda V.E. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Carrera, Betzabel N.S.; Watanabe, Shigueo [Universidade de Sao Paulo (IF/USP), Sao Paulo, SP (Brazil). Instituto de Fisica

    2015-07-01

    The thermoluminescence technique is widely used for both personal and for high-dose dosimetry. In this work, the thermoluminescence technique was utilized to study a new glass matrix, with nominal composition of 20Li{sub 2}CO{sub 3}.10Al{sub 2}O{sub 3}.20BaO.50B{sub 2}O{sub 3} (mol%), irradiated with different doses in a {sup 60}Co source. The glow curves and the dose-response curve were obtained for radiation doses between 50 Gy and 900 Gy. The results showed that this new glass matrix presents potential use in high-dose dosimetry. (author)

  11. Induced magnetic anisotropy in Si-free nanocrystalline soft magnetic materials: A transmission x-ray diffraction study

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, R., E-mail: rparsons01@gmail.com; Suzuki, K. [Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800 (Australia); Yanai, T. [Graduate School of Engineering, Nagasaki University, Nagasaki 852-8521 (Japan); Kishimoto, H.; Kato, A. [Toyota Motor Corporation, Mishuku, Susono, Shizuoka 410-1193 (Japan); Ohnuma, M. [Faculty and Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan)

    2015-05-07

    In order to better understand the origin of field-induced anisotropy (K{sub u}) in Si-free nanocrystalline soft magnetic alloys, the lattice spacing of the bcc-Fe phase in nanocrystalline Fe{sub 94−x}Nb{sub 6}B{sub x} (x = 10, 12, 14) alloys annealed under an applied magnetic field has been investigated by X-ray diffraction in transmission geometry (t-XRD) with the diffraction vector parallel and perpendicular to the field direction. The saturation magnetostriction (λ{sub s}) of nanocrystalline Fe{sub 94−x}Nb{sub 6}B{sub x} was found to increase linearly with the volume fraction of the residual amorphous phase and is well described by taking into account the volume-weighted average of two local λ{sub s} values for the bcc-Fe nanocrystallites (−5 ± 2 ppm) and the residual amorphous matrix (+8 ± 2 ppm). The lattice distortion required to produce the measured K{sub u} values (∼100 J/m{sup 3}) was estimated via the inverse magnetostrictive effect using the measured λ{sub s} values and was compared to the lattice spacing estimations made by t-XRD. The lattice strain required to produce K{sub u} under the magnetoelastic model was not observed by the t-XRD experiments and so the findings of this study suggest that the origin of magnetic field induced K{sub u} cannot be explained through the magnetoelastic effect.

  12. Synthesis and studies on microhardness of alkali zinc borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Subhashini,, E-mail: subhashini.p.p@gmail.com; Bhattacharya, Soumalya, E-mail: subhashini.p.p@gmail.com; Shashikala, H. D., E-mail: subhashini.p.p@gmail.com; Udayashankar, N. K., E-mail: subhashini.p.p@gmail.com [Department of Physics, National Institute of Technology Karnataka, Surathkal-575025 (India)

    2014-04-24

    The mixed alkali effect on zinc borate glasses have been reported. The glass systems of nominal composition 10Zn+xLi{sub 2}O+yNa{sub 2}O+80B{sub 2}O{sub 3} (x = y = 0, 5, 10, 15 mol%) were prepared using standard melt quenching method. The structural, physical and mechanical properties of the samples have been studied using X-ray diffraction(XRD), density measurement and Vickers hardness measurement, respectively. A consistent increase in the density was observed, which explains the role of the modifiers (Li{sub 2}O and Na{sub 2}O) in the network modification of borate structure. The molar volume is decreasing linearly with the alkali concentration, which is attributed to the conversion of tetrahedral boron (BO{sub 4/2}){sup −} into (BO{sub 3/2}){sup −}. The microhardness studies reveals the anisotropy nature of the material. It further confirms that the samples belong to hard glass category.

  13. REFINEMENT OF THE NEPHELINE DISCRIMINATOR: RESULTS OF A PHASE I STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K; James Newell, J; Tommy Edwards, T; David Best, D; Irene Reamer, I; Phyllis Workman, P

    2008-02-13

    studied HLW glasses with relatively high Al{sub 2}O{sub 3} compositions of 25 wt % or greater and nepheline discriminator values well below 0.62 have been shown to be free of nepheline crystallization upon quenching and slow cooling. Thus, the current nepheline discriminator equation also appears to be conservative for some HLW glass compositions. Refining the nepheline discriminator to include other important components and to reduce conservatism may provide access to high Al{sub 2}O{sub 3} concentration glass compositions for the DWPF, which could in turn allow access to higher waste loadings, decreased washing and improved waste throughput. The objective of this study was to develop and characterize a series of HLW glass compositions based on a projected composition of Sludge Batch 5 (SB5), the next sludge batch to be processed in the DWPF. The selected glass compositions all had nepheline discriminator values below the current limit of 0.62. They cover a range of locations on the SiO{sub 2}-Na{sub 2}O-Al{sub 2}O{sub 3} diagram. They also include varying amounts of B{sub 2}O{sub 3} and CaO to support an evaluation of the impact of these components on the propensity for nepheline crystallization. The results described in this report confirm that some conservatism exists in the current nepheline discriminator. Several glass compositions, particularly compositions that target higher Al{sub 2}O{sub 3} concentrations, were shown to be very durable (i.e., PCT responses that were more than an order of magnitude better than that of the Environmental Assessment benchmark glass) while their nepheline discriminator values were well below the current nepheline discriminator limit of 0.62. Increased concentrations of B{sub 2}O{sub 3} and increased concentrations of CaO were shown to improve durability responses and suppress the formation of nepheline. This provides incentive to revise the nepheline discriminator to reduce some of this conservatism and incorporate the influence of B{sub

  14. Recent progress of basic studies for neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Koji [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst

    2001-01-01

    Epi-thermal neutron irradiation for malignant brain tumors is the mainstream of recent studies in boron neutron capture therapy. To improve the depth dose distribution in water phantom, a LiF plate (5 mmt, 6 cm {phi}) is located in the front of center axis of KUR irradiation field. Thermal neutron flux at the center surface of the water phantom is shielded by the LiF plate. The depth and peripheral dose distribution of thermal neutron flux becomes to uniform. The boron dose at 6 cm in the depths of the phantom increases to about 1.71 times greater than the usual irradiation field. Two-kinds of nuclear medicines, Na{sub 2}B{sub 12}H{sub 11}SH(BSH) and Borono Phenyl Alanine (BPA), have been used for boron neutron capture therapy. BPA-ol, a new medicine of modified compound of the BPA can be used effectively on hyperthermia of cancer parts to 42 - 43degC. Cell death and mutagenesis of chinese hamster ovary cells (CHO) after pre-incubation with BPA and BSH are investigated for the validity of boron neutron capture therapy. The effects of BSH on the cell death and the mutagenesis are few in comparison with those of BPA. It is thought that the BSH is not accumulated in the cell. The effects of boron neutron capture therapy on sensitivity of intratumor quiescent and total cells are investigated. (Suetake, M.)

  15. Use of liver cell cultures in mutagenesis studies

    Energy Technology Data Exchange (ETDEWEB)

    Huberman, E.; Jones, C.A.

    1980-09-30

    A sensitive cell-mediated assay has been developed for testing the mutagenesis of liver carcinogens. Mutagenesis was detected in Chinese hamster V79 cells that were cocultivated with hepatocytes isolated after collagenase/hyaluronidase digestion of rat liver slices. Mutations were characterized by resistance to ouabain and 6-thioguanine. Seven of the nitrosamines, which are potent liver carcinogens, exhibited a mutagenic response. Mutagenesis with these carcinogens could be detected at ..mu..molar doses. The polyaromatic hydrocarbon benzo(a)pyrene, which is not a liver carcinogen, but can cause fibrosarcomas, was not mutagenic in this assay, but was mutagenic in a fibroblast-mediated assay. The liver carcinogen, aflatoxin B/sub 1/, which usually does not induce fibrosarcomas, exhibited an inverse situation; it was mutagenic for V79 cells in the presence of liver cells but not in the presence of fibroblasts. We suggest that the use of various cell types, including hepatocytes prepared by the slicing method for carcinogen metabolism, and mutable V79 cells offers a sensitive assay for determining the mutagenic potential of chemical carcinogens, and may also allow a study of their organ specificity.

  16. CEMS interface study of Fe(100)/Pd film structures

    Energy Technology Data Exchange (ETDEWEB)

    Kisters, G. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Festkoerperforschung; Sauer, C. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Festkoerperforschung; Tsymbal, E. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Festkoerperforschung; Zinn, W. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Festkoerperforschung

    1994-11-01

    The magnetic hyperfine fields B{sub hf} near the interface in epitaxial Fe(100)/Pd thin film structures were analyzed using in-situ {sup 57}Fe conversion electron Moessbauer spectroscopy. B{sub hf} is enhanced by about 12% in the 2nd Fe monolayer and approaches the Fe bulk value after a few oscillations within 8-10 Fe monolayers. This oscillating behavior can be described by a superposition of an exponential short-range and an RKKY-like long-range exchange interaction. (orig.)

  17. B^0_s Oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Casarsa, Massimo; /Fermilab

    2007-12-01

    For a long time the B{sub s}{sup 0}-{bar B}{sub s}{sup 0} system has eluded a complete investigation of its observables. Only recently the Tevatron experiments have accumulated sizable B{sub s}{sup 0} samples, which allow a direct and precise study of the system properties. This contribution reviews the most up-to-date measurements by the CDF and D0 Collaborations of the B{sub s}{sup 0}-{bar B}{sub s}{sup 0} system parameters: the mass and decay width differences, {Delta}m{sub s} and {Delta}{Lambda}{sub s}, between the heavy and light B{sub s}{sup 0} mass eigenstates, the average decay width {Lambda}{sub s}, and the CP-violating phase in the mixing {phi}{sub s}.

  18. REFINEMENT OF THE NEPHELINE DISCRIMINATOR: RESULTS OF A PHASE II STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K; Tommy Edwards, T

    2008-11-21

    Twenty five glass compositions were selected for a Phase II study to assess the potential for reducing the conservatism in the nepheline discriminator. The glass compositions were restricted to regions that fell within the validation ranges of the DWPF PCCS models. In addition, the liquidus temperature model was used to restrict the glass compositions so that they could all be melted at the same temperature. The nepheline discriminator was used to force the glass compositions into regions where nepheline formation was predicted to occur. The glasses were fabricated in the laboratory and characterized for crystallization and chemical durability after both quenching and slow cooling. Chemical analysis showed that the fabricated glasses met the target compositions. Nepheline was identified in one of the quenched glasses and several of the CCC glasses. There was no clear relationship between the types of crystallization that occurred in a particular glass and its location on the Al{sub 2}O{sub 3}-Na{sub 2}O-SiO{sub 2} ternary diagram. A partitioning algorithm was used to identify trends in crystallization behavior based on glass composition. Generally, for the CCC glasses MnO influenced the crystallization of spinels and B{sub 2}O{sub 3} and SiO{sub 2} influenced the crystallization of nepheline. Measured durability responses varied from acceptable to unacceptable depending on the glass composition and type and extent of crystallization that occurred. It was not possible to identify any linear effects of composition on chemical durability performance for this set of study glasses. The results were not sufficient to recommend modification of the current nepheline discriminator at this time. It is recommended that the next series of experiments continue to focus not only on compositional regions where the PCCS models are considered applicable (i.e., the model validation ranges), but also be restricted to compositional regions where acceptable glasses are predicted to be

  19. High pressure structural behavior of YGa{sub 2}: A combined experimental and theoretical study

    Energy Technology Data Exchange (ETDEWEB)

    Sekar, M., E-mail: sekarm@igcar.gov.in [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102, Tamil Nadu (India); Shekar, N.V. Chandra [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102, Tamil Nadu (India); Babu, R. [Chemical Group@, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102, Tamil Nadu (India); Sahu, P. Ch. [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102, Tamil Nadu (India); Sinha, A.K.; Upadhyay, Anuj; Singh, M.N. [Indus Synchrotron Utilization Division, Raja Ramanna Center for Advanced Technology, Indore-452013 (India); Babu, K. Ramesh; Appalakondaiah, S.; Vaitheeswaran, G. [Advanced Centre for Research in High Energy Materials, University of Hyderabad, Gachibowli, Hyderabad-500046, Telangana (India); Kanchana, V. [Department of Physics, Indian Institute of Technology Hyderabad, Ordnance Factory Estate, Yeddumailaram-502 205, Telangana (India)

    2015-03-15

    High pressure structural stability studies were carried out on YGa{sub 2} (AlB{sub 2} type structure at NTP, space group P6/mmm) up to a pressure of ~35 GPa using both laboratory based rotating anode and synchrotron X-ray sources. An isostructural transition with reduced c/a ratio, was observed at ~6 GPa and above ~17.5 GPa, the compound transformed to orthorhombic structure. Bulk modulus B{sub 0} for the parent and high pressure phases were estimated using Birch–Murnaghan and modified Birch–Murnaghan equation of state. Electronic structure calculations based on projector augmented wave method confirms the experimentally observed two high pressure structural transitions. The calculations also reveal that the ‘Ga’ networks remains as two dimensional in the high pressure isostructural phase, whereas the orthorhombic phase involves three dimensional networks of ‘Ga’ atoms interconnected by strong covalent bonds. - Graphical abstract: High pressure X-ray diffraction patterns of YGa{sub 2} up to ~35 GPa shows an isostructural phase transition at ~5 GPa and transition to an orthorhombic structure ~14 GPa. - Highlights: • High pressure structural stability studies were carried out on YGa{sub 2} up to 35 GPa. • An isostructural transition with reduced c/a ratio was observed above 6 GPa. • Above 17.5 GPa, the compound transformed to orthorhombic structure. • PAW based electronic structure calculations have been carried out. • Calculations confirm the experimentally observed structural transitions.

  20. A Neutronic Feasibility Study of an OPR-1000 Core Design with Boron-bearing Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Hoon; Park, Sang Yoon; Lee, Chung Chan; Yang, Yong Sik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    In Westinghouse plants, boron is mainly used as a form of the integral fuel burnable absorber (IFBA) with a thin coating of zirconium diboride (ZrB{sub 2}) or wet annular burnable absorber (WABA) with a hollow Al{sub 2}O{sub 3}+B{sub 4}C pellet. In OPR-1000, on the other hand, gadolinia is currently employed as a form of an admixture which consists of Gd{sub 2}O{sub 3} of 6∼8 w/o and UO{sub 2} of natural uranium. Recently, boron-bearing UO{sub 2} fuel (BBF) with the high density of greater than 94%TD has been developed by using a low temperature sintering technique. In this paper, the feasibility of replacing conventional gadolinia-bearing UO{sub 2} fuel (GBF) in OPR-1000 with newly developed boron-bearing fuel is evaluated. Neutronic feasibility study to utilize the BBF in OPR-1000 core has been performed. The results show that the OPR-1000 core design with the BBF is feasible and promising in neutronic aspects. Therefore, the use of the BBF in OPR-1000 can reduce the dependency on the rare material such as gadolinium. However, the burnout of the {sup 10}B isotope results in helium gas, so fuel performance related study with respect to helium generation is needed.

  1. Studies of transition states and radicals by negative ion photodetachment

    Energy Technology Data Exchange (ETDEWEB)

    Metz, R.B.

    1991-12-01

    Negative ion photodetachment is a versatile tool for the production and study of transient neutral species such as reaction intermediates and free radicals. Photodetachment of the stable XHY{sup {minus}} anion provides a direct spectroscopic probe of the transition state region of the potential energy surface for the neutral hydrogen transfer reaction X + HY {yields} XH + Y, where X and Y are halogen atoms. The technique is especially sensitive to resonances, which occur at a specific energy, but the spectra also show features due to direct scattering. We have used collinear adiabatic simulations of the photoelectron spectra to evaluate trail potential energy surfaces for the biomolecular reactions and have extended the adiabatic approach to three dimensions and used it to evaluate empirical potential energy surfaces for the I + Hl and Br + HI reactions. In addition, we have derived an empirical, collinear potential energy surface for the Br + HBr reaction that reproduces our experimental results and have extended this surface to three dimensions. Photodetachment of a negative ion can be also used to study neutral free radicals. We have studied the vibrational and electronic spectroscopy of CH{sub 2}NO{sub 2} by photoelectron spectroscopy of CH{sub 2}NO{sub 2}{sup {minus}}, determining the electron affinity of CH{sub 2}NO{sub 2}, gaining insight on the bonding of the {sup 2}B{sub 1} ground state and observing the {sup 2}A{sub 2} excited state for the first time. Negative ion photodetachment also provides a novel and versatile source of mass-selected, jet-cooled free radicals. We have studied the photodissociation of CH{sub 2}NO{sub 2} at 270, 235, and 208 nm, obtaining information on the dissociation products by measuring the kinetic energy release in the photodissociation.

  2. Ab initio study of pressure induced structural and electronic properties in TmPo

    Energy Technology Data Exchange (ETDEWEB)

    Makode, Chandrabhan, E-mail: cbmakode@gmail.com; Pataiya, Jagdish; Sanyal, Sankar P. [Department of Physics, Barkatullah University, Bhopal-462026 (India); Panwar, Y. S.; Aynyas, Mahendra [Department of Physics, C.S.A. Govt. P.G. College, Sehore-466001 (India)

    2015-06-24

    We report an ab initio calculation of pressure induced structural phase transition and electronic properties of Thulium Polonide (TmPo).The total energy as a function of volume is obtained by means of self-consistent tight binding linear muffin-tin-orbital (TB-LMTO) method within the local density approximation (LDA). It is found that TmPo is stable in NaCl-type (B{sub 1}-phase) structure to CsCl-type (B{sub 2}-phase) structure of this compound in the pressure range of 7.0 GPa. We also calculate the lattice parameter (a{sub 0}), bulk modulus (B{sub 0}), band structure and density of states. From energy diagram it is observed that TmPo exhibit metallic behavior. The calculated values of equilibrium lattice parameter and bulk modulus are in general good agreement.

  3. Effects of boron addition on the formation of MoSi{sub 2} by combustion synthesis mode

    Energy Technology Data Exchange (ETDEWEB)

    Feng Peizhong, E-mail: fengroad@163.co [School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116 (China) and School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116 (China); Wu Jie [School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116 (China); Islam, S.H. [Department of Metallurgical Engineering, NED University of Engineering and Technology, University Road, Karachi 75270 (Pakistan); Liu Weisheng; Niu Jinan; Wang Xiaohong; Qiang Yinghuai [School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116 (China)

    2010-04-02

    The combustion synthesis behavior of Mo-Si-B powder was investigated. Test specimens with nominal compositions including MoSi{sub 2}, Mo(Si{sub 0.975}B{sub 0.025}){sub 2}, Mo(Si{sub 0.95}B{sub 0.05}){sub 2}, Mo(Si{sub 0.925}B{sub 0.075}){sub 2} and Mo(Si{sub 0.9}B{sub 0.1}){sub 2} were employed. The combustion mode, propagation velocity of combustion wave, combustion temperature and combustion product structure were studied. The results showed that the combustion wave propagated along a spiral trajectory till reaching the bottom of the compacts. The combustion temperature was increased by the addition of boron, to as high as 1922 K in the case of the Mo(Si{sub 0.95}B{sub 0.05}){sub 2} sample. However, the flame-front propagation velocity decreased as a result of the addition of boron. The X-ray diffraction results showed that the combustion products of the Mo(Si{sub 0.975}B{sub 0.025}){sub 2} and Mo(Si{sub 0.9}B{sub 0.1}){sub 2} samples were composed of MoSi{sub 2} with minor MoB. Those of the Mo(Si{sub 0.95}B{sub 0.05}){sub 2} and Mo(Si{sub 0.925}B{sub 0.075}){sub 2} samples were composed of MoSi{sub 2} with minor MoB and MoB{sub 2}. And traces of Mo{sub 2}B{sub 5} were identified in the Mo(Si{sub 0.95}B{sub 0.05}){sub 2} sample.

  4. B(s) properties at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ceballos, Guillelmo; /Cantabria U., Santander

    2005-11-01

    The Tevatron collider at Fermilab provides a very rich environment for the study B{sub s} mesons. In this paper they show a few selected topics from the CDF and D0 collaborations, giving special attention to the B{sub s} Mixing analyses. This note corresponds to the proceedings of the Hadron Collider Physics 2005 conference.

  5. Moessbauer study of the cubic Laves phase intermetallic compound TmFe/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Bleaney, B.; Bowden, G.J.; Cadogan, J.M. (New South Wales Univ., Kensington (Australia). School of Physics); Day, R.K.; Dunlop, J.B. (Commonwealth Scientific and Industrial Research Organization, Lindfield (Australia). Div. of Applied Physics)

    1982-04-01

    The results of a /sup 169/Tm and /sup 57/Fe Moessbauer study of the cubic Laves compound TmFe/sub 2/ over the temperature range 1.3-550 K are presented and discussed. The new results are used, in conjunction with existing NMR, Moessbauer and magnetic anisotropy data for TmFe/sub 2/ and Tm metal, to deduce a value of Psub(4f) 536 +- 14 MHz for the saturation value of the first excited state of the /sup 169/Tm nucleus. Estimates are also given for the exchange field ..mu..sub(B)Bsub(ex)(T = O K)/ksub(B) = 153 +- 3 K acting on the Tm/sup 3 +/ ion in TmFe/sub 2/, the quadrupole moment of the I = 3/2 state of the /sup 169/Tm nucleus. Q = -1.36 +- 0.11 b, and the lattice contribution to the nuclear quadrupole interaction in Tm metal, Psub(c) = -54.8 +- 5 MHz (for Q = -1.20 +- 0.07 b) and Psub(c) = -61 +- 8 MHz (for Q = -1.36 +- 0.11 b). In addition estimates are given for the various transferred and parent hyperfine fields in TmFe.

  6. Molecular dynamics study of structural changes versus deposited energy dose in a sodium borosilicate glass

    Energy Technology Data Exchange (ETDEWEB)

    Bureau, G.; Delaye, J.M.; Peuget, S. [DEN/DTCD/SECM, CEA Marcoule, BP 17171, Bagnols-sur-Ceze cedex, 30207 (France); Calas, G. [IMPMC, 140 rue de Lourmel, Paris, 75015 (France)

    2008-07-01

    Assessing the long-term behavior of nuclear glass implies evaluating the impact of cumulative alpha decay induced by the minor actinides it contains. When subjected to alpha decay ({sup 244}Cm-doped glass specimens) or to external ion irradiation, some macroscopic properties vary appreciably with the dose. Above a given dose level, the properties do not evolve any more. To improve our understanding of these modifications, studies are carried out on simplified glass compositions (three oxides SiO{sub 2}, B{sub 2}O{sub 3}, Na{sub 2}O), modeled by molecular dynamics in which irradiation effects are simulated by accelerating uranium projectiles. Accumulation of displacements cascades have been performed up to 4.5*10{sup 20} keV/cm{sup 3} nuclear energy deposited in the glass. The density variations observed in actinide-doped materials is qualitatively reproduced. At high doses, the swelling tends to stabilize. Marples model is used to fit the glass swelling versus the deposited energy dose, giving the volume damaged per projectile. This volume approximates the cascade core volume, suggesting that the underlying mechanisms of volume expansion are contained in the cascade core and are thus related to the highest energy events: atom ejection and thermal quenching. On the contrary, the volumetric parameter of the Marples model applied to the other structural properties is related to a volume corresponding to the core + periphery of the cascades. (authors)

  7. Studies on the oxygen precipitation in highly boron doped silicon; Untersuchungen zur Sauerstoffausscheidung in hoch bordotiertem Silicium

    Energy Technology Data Exchange (ETDEWEB)

    Zschorsch, Markus

    2007-12-14

    The aim of this thesis was the getting of new knowledge on the elucidation of the oxygen precipitation in highly doped silicon. In the study of the early phases of the oxygen precipitation boron-oxygen complexes and their kinetics could be indirectly detected. These arise already during the cooling of the crystal and can be destroyed by subsequent temperature processes. The formation of the here as BO assumed species during the cooling after the silicon crystal fabrication could be numerically reproduced. Furthermore the study of early precipitation phases by means of neutron small angle scattering a maximum of the oxygen precipitation at {rho}=9 m{omega}cm. It could be shown that the decreasing of this at increasing boron concentration can be most probably reduced to boron precipitations. Furthermore it could be shown that after a tempering time of 24 hours at 700 C in silicon with {rho}=9 m{omega}cm platelet-shaped precipitates form. By the study of the precipitate growth could be shown that also in this phase the oxygen precipitation in silicon is strongest with a specific resistance of {rho}=9 m{omega}cm. By means of FTIR spectroscopy a new absorption band at a wave number of 1038 cm{sup -1} was found, which could be assigned to a boron species. By different experiments it is considered as probable that at this species it deals with BI respectively B{sub 2}I complexes.

  8. Essential and toxic element concentrations in blood and urine and their associations with diet: Results from a Norwegian population study including high-consumers of seafood and game

    Energy Technology Data Exchange (ETDEWEB)

    Birgisdottir, B.E.; Knutsen, H.K.; Haugen, M.; Gjelstad, I.M. [Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo (Norway); Jenssen, M.T.S. [Norwegian Institute for Water Research, Oslo (Norway); Ellingsen, D.G.; Thomassen, Y. [National Institute of Occupational Health, Oslo (Norway); Alexander, J. [Office of the Director-General, Norwegian Institute of Public Health, Oslo (Norway); Meltzer, H.M. [Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo (Norway); Brantsæter, A.L., E-mail: Anne.Lise.Brantsaeter@fhi.no [Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo (Norway)

    2013-10-01

    The first aim of the study was to evaluate calculated dietary intake and concentrations measured in blood or urine of essential and toxic elements in relation to nutritional and toxicological reference values. The second aim was to identify patterns of the element concentrations in blood and urine and to identify possible dietary determinants of the concentrations of these elements. Adults with a known high consumption of environmental contaminants (n = 111), and a random sample of controls (n = 76) answered a validated food frequency questionnaire (FFQ). Complete data on biological measures were available for 179 individuals. Blood and urine samples were analyzed for selenium, iodine, arsenic, mercury, cadmium and lead. Principal component analysis was used to identify underlying patterns of correlated blood and urine concentrations. The calculated intakes of selenium, iodine, inorganic arsenic and mercury were within guideline levels. For cadmium 24% of the high consumer group and 8% of the control group had intakes above the tolerable weekly intake. Concentrations of lead in blood exceeded the bench-mark dose lower confidence limits for some participants. However, overall, the examined exposures did not give rise to nutritional or toxicological concerns. Game consumption was associated with lead in blood (B{sub ln} 0.021; 95%CI:0.010, 0.031) and wine consumption. Seafood consumption was associated with urinary cadmium in non-smokers (B{sub ln} 0.009; 95%CI:0.003, 0.015). A novel finding was a distinct pattern of positively associated biological markers, comprising iodine, selenium, arsenic and mercury (eigenvalue 3.8), reflecting seafood intake (B 0.007; 95%CI:0.004, 0.010). The study clearly demonstrates the significance of seafood as a source of both essential nutrients and toxic elements simultaneously and shows that exposure to various essential and toxic elements can be intertwined. - Highlights: • A study on interplay and sources of six different

  9. Structural studies of some phospho-borate glasses using ultrasonic pulse-echo technique, DSC and IR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gaafar, M.S., E-mail: mohamed_s_gaafar@hotmail.co [Ultrasonic Laboratory, National Institute for Standards, Tersa Street, P.O. Box 136, El-Haram, El-Giza 12211 (Egypt); Afifi, H.A. [Ultrasonic Laboratory, National Institute for Standards, Tersa Street, P.O. Box 136, El-Haram, El-Giza 12211 (Egypt); Mekawy, M.M. [Thermometry Laboratory, National Institute for Standards, Tersa Street, P.O. Box 136, El-Haram, El-Giza 12211 (Egypt)

    2009-06-01

    Glasses in the system (95-x) [0.25 Na{sub 2}O-0.75 B{sub 2}O{sub 3}]-x P{sub 2}O{sub 5}-5 Fe{sub 2}O{sub 3} (0<=x<=15 mol%), have been prepared by the melt quenching technique. Elastic properties and FT-IR spectroscopic studies have been employed to study the role of P{sub 2}O{sub 5} on the structure of the glass system. Elastic properties Poisson's ratio, micro-hardness and Debye temperature have been investigated using sound wave velocity measurements at 4 MHz (both longitudinal and shear) at room temperature. The results showed that the density and the molar volume increase as both sound velocities and the determined glass transition temperatures decrease with increasing the contents of P{sub 2}O{sub 5}. Infrared spectra of the glasses reveal that the borate network consists of diborate units and is affected by the increase in the concentration of P{sub 2}O{sub 5} content as a second network former. These results are interpreted in terms of the replacement of the diborate units with B-O-B bridges by phosphate units with non-bridging oxygens (NBOs). Therefore, the elastic moduli are observed to decrease with the increase in P{sub 2}O{sub 5} content.

  10. Effect of titanium ion substitution in the barium hexaferrite studied by Moessbauer spectroscopy and X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Quiroz, Pamela, E-mail: pamela.quiroz-penaranda@tu-ilmenau.de; Halbedel, Bernd [Ilmenau University of Technology, Department of Inorganic-Nonmetallic Materials, Institute of Materials Engineering (Germany); Bustamante, Angel, E-mail: angelbd1@gmail.com [San Marcos National University, Laboratory of Ceramics and Nanomaterials, Faculty of Physical Sciences (Peru); Gonzalez, Juan C. [Materials Science Institute of Sevilla - CSIC, Surfaces Research Group-Interfaces and Thin Films (Spain)

    2011-11-15

    A series of M-type barium hexaferrite has been synthesized in a glass melt by partially substituting the Fe{sub 2}O{sub 3} with TiO{sub 2} for investigation of their structure. The glass melt has the basic composition (mol%): 40 BaO + 33 B{sub 2}O{sub 3} + (27-x) Fe{sub 2}O{sub 3} + x TiO{sub 2} with x = 0, 3.6, 5.4 and 7.2 mol% TiO{sub 2}. The substituted ferrites were studied by means of X-ray diffraction, Moessbauer spectroscopy and vibration sample magnetometer. X-ray diffraction studies revealed that not all samples have a single ferritic phase, a small second phase corresponding to BaTi{sub 6}O{sub 13} was also observed to form. The Moessbauer spectra changed from magnetically ordered (x = 0) to magnetically ordered with strong line broadening. Moreover, the broadening increases with TiO{sub 2} content. The Moessbauer parameters suggested that Ti{sup 4 + } occupies the 2a and 12k crystal sites, and the Ti{sup 4 + } substitution on the 2b and 4f{sub 2} site also occurs at high melt dopings. Therefore, coercivity and saturation magnetization decreased.

  11. Excited state non-adiabatic dynamics of N-methylpyrrole: A time-resolved photoelectron spectroscopy and quantum dynamics study

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Guorong [National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023 (China); Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Neville, Simon P. [Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5 (Canada); Schalk, Oliver [National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Department of Physics, AlbaNova University Center, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm (Sweden); Sekikawa, Taro [Department of Applied Physics, Hokkaido University, Kita-13 Nishi-8, Kita-ku, Sapporo 060-8628 (Japan); Ashfold, Michael N. R. [School of Chemistry, University of Bristol, Bristol BS8 1TS (United Kingdom); Worth, Graham A. [School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Stolow, Albert, E-mail: astolow@uottawa.ca [National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5 (Canada); Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5 (Canada)

    2016-01-07

    The dynamics of N-methylpyrrole following excitation at wavelengths in the range 241.5-217.0 nm were studied using a combination of time-resolved photoelectron spectroscopy (TRPES), ab initio quantum dynamics calculations using the multi-layer multi-configurational time-dependent Hartree method, as well as high-level photoionization cross section calculations. Excitation at 241.5 and 236.2 nm results in population of the A{sub 2}(πσ{sup ∗}) state, in agreement with previous studies. Excitation at 217.0 nm prepares the previously neglected B{sub 1}(π3p{sub y}) Rydberg state, followed by prompt internal conversion to the A{sub 2}(πσ{sup ∗}) state. In contrast with the photoinduced dynamics of pyrrole, the lifetime of the wavepacket in the A{sub 2}(πσ{sup ∗}) state was found to vary with excitation wavelength, decreasing by one order of magnitude upon tuning from 241.5 nm to 236.2 nm and by more than three orders of magnitude when excited at 217.0 nm. The order of magnitude difference in lifetimes measured at the longer excitation wavelengths is attributed to vibrational excitation in the A{sub 2}(πσ{sup ∗}) state, facilitating wavepacket motion around the potential barrier in the N–CH{sub 3} dissociation coordinate.

  12. Controlled and selective placement of boron subphthalocyanines on either chain end of polymers synthesized by nitroxide mediated polymerization

    Directory of Open Access Journals (Sweden)

    Benoît H. Lessard

    2015-10-01

    Full Text Available In previous studies, we synthesized the first organic light emitting diode (OLED using boron subphthalocyanines (BsubPcs based polymers. When designing new polymer materials for organic electronic applications such as OLEDs or organic photovoltaic (OPV devices it is important to consider not only the contribution of each monomer but also the polymer chain ends. In this paper we establish a post-polymerization strategy to couple BsubPcs onto either the α- or the ω-chain end using chemically selective BsubPc derivatives. We outline how the chain ends of two representative polymers, poly(styrene (PS and poly(n-butylacrylate (BA, synthesized by nitroxide mediated polymerization (NMP, using BlocBuilder-MA as the initiating species, can be chemically modified by the incorporation of BsubPc chromophores. The addition of the BsubPc chromophore was confirmed through the use of a photodiode array detector (PDA connected in-line with a gel permeation chromatography (GPC setup. These findings represent the first reported method for the controlled and selective placement of a BsubPc chromophores on either end of a polymer produced by NMP. This strategy will therefore be utilized to make next generation BsubPc polymers for OLEDs and OPV devices. The extremely high molar extinction coefficient of BsubPc also make these polymers ideally suited for dye-labelling of polymers.

  13. In search of the X{sub 2}BO and X{sub 2}BS (X = H, F) free radicals: Ab initio studies of their spectroscopic signatures

    Energy Technology Data Exchange (ETDEWEB)

    Clouthier, Dennis J., E-mail: dclaser@uky.edu [Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506-0055 (United States)

    2014-12-28

    The F{sub 2}BO free radical is a known, although little studied, species but similar X{sub 2}BY (X = H, D, F; Y = O, S) molecules are largely unknown. High level ab initio methods have been used to predict the molecular structures, vibrational frequencies (in cm{sup −1}), and relative energies of the ground and first two excited electronic states of these free radicals, as an aid to their eventual spectroscopic identification. The chosen theoretical methods and basis sets were tested on F{sub 2}BO and found to give good agreement with the known experimental quantities. In particular, complete basis set extrapolations of coupled-cluster single and doubles with perturbative triple excitations/aug-cc-pVXZ (X = 3, 4, 5) energies gave excellent electronic term values, due to small changes in geometry between states and the lack of significant multireference character in the wavefunctions. The radicals are found to have planar C{sub 2v} geometries in the X{sup ~2}B{sub 2} ground state, the low-lying A{sup ~2}B{sub 1} first excited state, and the higher B{sup ~2}A{sub 1} state. Some of these radicals have very small ground state dipole moments hindering microwave measurements. Infrared studies in matrices or in the gas phase may be possible although the fundamentals of H{sub 2}BO and H{sub 2}BS are quite weak. The most promising method of identifying these species in the gas phase appears to be absorption or laser-induced fluorescence spectroscopy through the allowed B{sup ~}-X{sup ~} transitions which occur in the visible-near UV region of the electromagnetic spectrum. The ab initio results have been used to calculate the Franck-Condon profiles of the absorption and emission spectra, and the rotational structure of the B{sup ~}-X{sup ~}0{sub 0}{sup 0} bands has been simulated. The calculated single vibronic level emission spectra provide a unique, readily recognizable fingerprint of each particular radical, facilitating the experimental identification of new X{sub 2}BY

  14. Spectral hole burning studies of photosystem II

    Energy Technology Data Exchange (ETDEWEB)

    Chang, H.C.

    1995-11-01

    Low temperature absorption and hole burning spectroscopies were applied to the D1-D2-cyt b{sub 559} and the CP47 and CP43 antenna protein complexes of Photosystem H from higher plants. Low temperature transient and persistent hole-burning data and theoretical calculations on the kinetics and temperature dependence of the P680 hole profile are presented and provide convincing support for the linker model. Implicit in the linker model is that the 684-nm-absorbing Chl a serve to shuttle energy from the proximal antenna complex to reaction center. The stoichiometry of isolated Photosystem H Reaction Center (PSII RC) in several different preparations is also discussed. The additional Chl a are due to 684-nm-absorbing Chl a, some contamination by the CP47 complex, and non-native Chl a absorbing near 670 nm. In the CP47 protein complex, attention is focused on the lower energy chlorophyll a Q{sub y}-states. High pressure hole-burning studies of PSII RC revealed for the first time a strong pressure effect on the primary electron transfer dynamics. The 4.2 K lifetime of P680*, the primary donor state, increases from 2.0 ps to 7.0 ps as pressure increases from 0.1 to 267 MPa. Importantly, this effect is irreversible (plastic) while the pressure induced effect on the low temperature absorption and non-line narrowed P680 hole spectra are reversible (elastic). Nonadiabatic rate expressions, which take into account the distribution of energy gap values, are used to estimate the linear pressure shift of the acceptor state energy for both the superexchange and two-step mechanisms for primary charge separation. It was found that the pressure dependence could be explained with a linear pressure shift of {approximately} 1 cm{sup -1}/MPa in magnitude for the acceptor state. The results point to the marriage of hole burning and high pressures as having considerable potential for the study of primary transport dynamics in reaction centers and antenna complexes.

  15. X-ray photoelectron spectroscopy studies of MgB{sub 2} for valence state of Mg

    Energy Technology Data Exchange (ETDEWEB)

    Talapatra, A. [Department of Physics, Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata 700 064 (India); Bandyopadhyay, S.K. [Department of Physics, Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata 700 064 (India)]. E-mail: skband@veccal.ernet.in; Sen, Pintu [Department of Physics, Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata 700 064 (India); Barat, P. [Department of Physics, Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata 700 064 (India); Mukherjee, S. [Saha Institute of Nuclear Physics, 1/AF, Bidhan Nagar, Kolkata 700 064 (India); Mukherjee, M. [Saha Institute of Nuclear Physics, 1/AF, Bidhan Nagar, Kolkata 700 064 (India)

    2005-03-01

    Core level X-ray photoelectron spectroscopy (XPS) studies have been carried out on polycrystalline MgB{sub 2} pellets over the whole binding energy range with a view to having an idea of the charge state of magnesium (Mg). We observe three distinct peaks in Mg 2p spectra at 49.3 eV (trace), 51.3 eV (major) and 54.0 eV (trace), corresponding to metallic Mg, MgB{sub 2} and MgCO{sub 3} or, divalent Mg species, respectively. Similar trend has been noticed in Mg 2s spectra. The binding energy of Mg in MgB{sub 2} is lower than that corresponding to Mg(2+), indicative of the fact that the charge state of Mg in MgB{sub 2} is less than (2+). Lowering of the formal charge of Mg promotes the {sigma} {yields} {pi} electron transfer in boron (B) giving rise to holes on the top of the {sigma}-band which are involved in coupling with B E{sub 2g} phonons for superconductivity. Through this charge transfer, Mg plays a positive role in hole superconductivity. B 1s spectra consist of three peaks corresponding to MgB{sub 2}, boron and B{sub 2}O{sub 3}. There is also evidence of MgO due to surface oxidation as seen from O 1s spectra.

  16. EM-21 HIGHER WASTE LOADING GLASSES FOR ENHANCED DOE HIGH-LEVEL WASTE MELTER THROUGHPUT STUDIES - 10194

    Energy Technology Data Exchange (ETDEWEB)

    Raszewski, F.; Peeler, D.; Edwards, T.

    2009-11-18

    Supplemental validation data has been generated that will be used to determine the applicability of the current Defense Waste Processing Facility (DWPF) liquidus temperature (T{sub L}) model to expanded DWPF glass regions of interest based on higher waste loadings. For those study glasses which had very close compositional overlap with the model development and/or model validation ranges (except TiO{sub 2} and MgO concentrations), there was very little difference in the predicted and measured TL values, even though the TiO{sub 2} contents were above the 2 wt% upper limit. The results indicate that the current T{sub L} model is applicable in these compositional regions. As the compositional overlap between the model validation ranges diverged from the target glass compositions, the T{sub L} data suggest that the model under-predicted the measured values. These discrepancies imply that there are individual oxides or their combinations that were outside of the model development and/or validation range over which the model was previously assessed. These oxides include B{sub 2}O{sub 3}, SiO{sub 2}, MnO, TiO{sub 2} and/or their combinations. More data is required to fill in these anticipated DWPF compositional regions so that the model coefficients could be refit to account for these differences.

  17. High affinity dopamine D2 receptor radioligands. 3. [[sup 123]I] and [[sup 125]I]epidepride: In vivo studies in rhesus monkey brain and comparison with in vitro pharmacokinetics in rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, R.M.; Votaw, J.R.; Schmidt, D.E.; Ansari, M.S.; Holdeman, K.P.; Paulis, T. de; Clanton, J.A.; Pfeffer, R.; Manning, R.G.; Ebert, M.H. (Vanderbilt Univ., Nashville, TN (United States))

    1993-01-01

    Studies of [[sup 123]I]epidepride uptake in rhesus monkey brain were performed using single photon tomography. Striatal uptake peaked at 0.85% of administered dose/g at 107 min post-injection, then declined slowly to 0.70% of administered dose/g at 6 h. Striatal:posterior brain ratios rose from 2 at 25 min to 6.8 at 105 min, to 15 at 4 h and to 58 at 6.4 h. [[sup 123]I]Epidepride was displaced by haloperidol (0.1 and 1 mg/kg) with a half-life of washout of 55 min. Little displacement of [[sup 123]I]epidepride was observed following administration of 1 or 2 mg/kg d-amphetamine, respectively, indicating [[sup 123]I]epidepride is not easily displaced by endogenous dopamine. In vitro equilibrium binding studies with [[sup 125]I]epidepride using rat striatum revealed a K[sub D] of 46 pM and B[sub max] of 33 pmol/g tissue at 37[degrees]C, while at 25[degrees]C the K[sub D] was 25 pM and the B[sub max] 32 pmol/g tissue. In vitro kinetic analysis of association and dissociation curves revealed a half-life for receptor dissociation at 37[degrees]C of 15 min and 79--90 min at 25[degrees]C. Allowing for the temperature difference, there is good correspondence between in vivo and in vitro dissociation kinetics at 25[degrees]C. Increasing in vitro incubation temperature from 25 to 37[degrees]C caused a 6-fold increase in the dissociation rate, suggesting that there is a change in binding kinetics at the dopamine D2 receptor at 37[degrees]C compared to in vivo binding. The results of this study indicate that [[sup 123]I]epidepride is an excellent radioligand for SPECT studies of the dopamine D2 receptor in man. 34 refs., 4 figs.

  18. High-pressure and high-temperature studies on oxide garnets

    Energy Technology Data Exchange (ETDEWEB)

    Hua, H.; Mirov, S.; Vohra, Y.K. [Department of Physics, University of Alabama at Birmingham (UAB), Birmingham, Alabama 35294-1170 (United States)

    1996-09-01

    We report high-pressure and high-temperature studies on a series of oxide garnets of chemical composition {ital A}{sub 3}{ital B}{sub 2}{ital C}{sub 3}O{sub 12}. The members of this family investigated are gadolinium scandium gallium garnet (GSGG), gadolinium gallium garnet (GGG), and yttrium aluminum garnet (YAG). The GSGG and GGG are doped with both neodymium and chromium while the YAG is doped only with neodymium. Photoluminescence, synchrotron x-ray-diffraction, and laser heating studies were carried out in a diamond-anvil cell. Variety of optical sensors (ruby, Sm-doped YAG) and x-ray pressure marker (copper) were employed for pressure measurement. Pressure-induced amorphization was observed in GSGG at 58{plus_minus}3 GPa and GGG at 84{plus_minus}4 GPa by x-ray-diffraction studies. The photoluminescence studies show only gradual broadening of emission bands through the amorphization transition. On increasing pressure beyond amorphization, very broad and featureless emission bands were observed in the fluorescence spectra at 77{plus_minus}2 GPa for GSGG and at 88{plus_minus}2 GPa for GGG. Laser heating of the pressure-induced amorphous phase in GSGG caused recrystallization to the stable cubic phase. High-pressure x-ray study on YAG shows that it retains cubic phase up to 101{plus_minus}4 GPa. A pressure-volume relation for each member of the oxide garnet at ambient temperatures is presented, structural transformation mechanisms, and application of oxide garnets as pressure sensors are also discussed. {copyright} {ital 1996 The American Physical Society.}

  19. Soft X-ray emission studies of biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Kurmaev, E.Z. E-mail: kurmaev@ifmlrs.uran.ru; Werner, J.P.; Moewes, A.; Chiuzbaian, S.; Bach, M.; Ching, W.-Y.; Motozaki, W.; Otsuka, T.; Matsuya, S.; Endo, K.; Neumann, M

    2004-07-01

    Soft X-ray fluorescence measurements are used to characterize three groups of biomaterials: Vitamin B{sub 12} and derivatives, antioxidants (aspirin and paracetamol), and human teeth. We show that the chemical bonding in Vitamin B{sub 12} is characterized by the strong Co-C bond and the relatively weak Co-N bond. The Co-C bond in cyanocobalamin is found to be stronger than that of methylcobalamin leading to their different biological activity. The chemical bonding of paracetamol and aspirin is characterized by the formation of oxygen lone-pair {pi}-orbitals, which can neutralize free radicals and therefore be related to antioxidant activity of these compounds. Carbon K{alpha} emission spectra of a caries lesion suggest that the CaCO{sub 3} like phase exists in sound enamel and that a selective loss of carbonate occurs during the early stages of a caries attack.

  20. Role of Mo in the local configuration and structure stabilization of amorphous steels, a Synchrotron X-ray diffraction and Moessbauer study

    Energy Technology Data Exchange (ETDEWEB)

    Pineda, E., E-mail: eloi.pineda@upc.edu [Departament de Fisica i Enginyeria Nuclear, ESAB, Universitat Politecnica de Catalunya, Esteve Terradas 8, 08860 Castelldefels (Spain); Bruna, P. [Departament de Fisica Aplicada, EPSC, Universitat Politecnica de Catalunya, Avda. del Canal Olimpic s/n, 08860 Castelldefels (Spain); Serrano, J. [Departament de Fisica Aplicada, EPSC, Universitat Politecnica de Catalunya, Avda. del Canal Olimpic s/n, 08860 Castelldefels (Spain); Institucio Catalana de Recerca i Estudis Avancats, Catalonia (Spain); Torrens-Serra, J. [Grup de Nanomaterials i Microsistemes, Departament de Fisica, Universitat Autonoma de Barcelona. Edifici Cc, 08193 Bellaterra (Spain); Crespo, D. [Departament de Fisica Aplicada, EPSC, Universitat Politecnica de Catalunya, Avda. del Canal Olimpic s/n, 08860 Castelldefels (Spain)

    2011-06-15

    Highlights: > Mo substitution of Fe atoms stabilizes structure in amorphous steels. > Moessbauer spectroscopy evidences two distinct Fe atoms environments in the amorphous structure of the Mo containing glassy alloys. > Structural relaxation before crystallization produces homogenization of the Fe environments reducing population of sites with low hyperfine fields. - Abstract: Amorphous steels are promising materials with potential structural applications. The glass-forming ability (GFA) and mechanical properties of metallic glasses are intimately related to the local structure. In Fe-based alloys, Cr and Mo content seem to play a key role in stabilizing the amorphous atomic-level structure. Here we present a study on the effects of changing Mo content in Fe{sub 72-x}C{sub 7}Si{sub 3.3}B{sub 5.5}P{sub 8.7}Cr{sub 2.3}Al{sub 2}Mo{sub x} amorphous steels. We study the local structure of these alloys by Synchrotron X-ray diffraction and Moessbauer spectroscopy. The results show how the amorphous phase evolves from a ferromagnetic Fe-rich structure to a structure with predominance of paramagnetic environments with the increase of Mo content. The changes in the distribution of magnetic environments cannot be attributed only to the Fe-Mo substitution but to a change of local configuration in the amorphous phase.

  1. Spectroscopic studies of neutral and chemically oxidized species of β-carotene, lycopene and norbixin in CH{sub 2}Cl{sub 2}: Fluorescence from intermediate compounds

    Energy Technology Data Exchange (ETDEWEB)

    Alwis, D.D.D.H [Department of Chemistry, The Open University of Sri Lanka, Nawala (Sri Lanka); Department of Chemistry, University of Sri Jayewardenepura, Nugegoda (Sri Lanka); Chandrika, U.G. [Department of Biochemistry, University of Sri Jayewardenepura, Nugegoda (Sri Lanka); Jayaweera, P.M., E-mail: pradeep@sjp.ac.lk [Department of Chemistry, University of Sri Jayewardenepura, Nugegoda (Sri Lanka)

    2015-02-15

    Radical cations, dications and oxidized intermediate species of three carotenoids, namely, β-carotene, lycopene and norbixin, were generated in CH{sub 2}Cl{sub 2} solutions via chemical oxidation using anhydrous FeCl{sub 3}. UV–vis, fluorescence and fluorescence-excitation spectroscopic studies were performed to understand and compare the nature of intermediate species generated during the chemical oxidation process and subsequent degradation. The intense emission observed at 550 nm can be assigned to the S{sub 2}→S{sub 0} (1{sup 1}B{sub u}→1{sup 1}A{sub g}) transition of the carotenoid molecules. The 350 nm excitation during the oxidation process for β-carotene, lycopene and norbixin exhibit intense fluorescence peaks at 492 nm, 493 nm and 500 nm, respectively. These peaks are assigned to intermediate peroxy/epoxy compounds of the three molecules that are formed with molecular oxygen prior to the formation of oxidized short-chain stable compounds. - Highlights: • Fluorescence and UV–vis studies on β-carotene, lycopene and norbixin. • Oxidation, induced by FeCl{sub 3} in CH{sub 2}Cl{sub 2} shows blue shifted fluorescence peaks. • Fluorescence peaks were assigned to intermediate peroxy/epoxy forms of carotenoids. • The D0→D3 transition of radical cations are observed in the near IR region.

  2. Predicted boron-carbide compounds: A first-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, De Yu; Yan, Qian; Wang, Bing; Wang, Yuan Xu, E-mail: wangyx@henu.edu.cn; Yang, Jueming; Yang, Gui [Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004 (China)

    2014-06-14

    By using developed particle swarm optimization algorithm on crystal structural prediction, we have explored the possible crystal structures of B-C system. Their structures, stability, elastic properties, electronic structure, and chemical bonding have been investigated by first-principles calculations with density functional theory. The results show that all the predicted structures are mechanically and dynamically stable. An analysis of calculated enthalpy with pressure indicates that increasing of boron content will increase the stability of boron carbides under low pressure. Moreover, the boron carbides with rich carbon content become more stable under high pressure. The negative formation energy of predicted B{sub 5}C indicates its high stability. The density of states of B{sub 5}C show that it is p-type semiconducting. The calculated theoretical Vickers hardnesses of B-C exceed 40 GPa except B{sub 4}C, BC, and BC{sub 4}, indicating they are potential superhard materials. An analysis of Debye temperature and electronic localization function provides further understanding chemical and physical properties of boron carbide.

  3. Study of the spin-glass transition in FeCr{sub 2x}In{sub 2-2x}S{sub 4} thiospinel

    Energy Technology Data Exchange (ETDEWEB)

    Goya, G.F. E-mail: goya@macbeth.if.usp.br; Rechenberg, H.R.; Sagredo, V

    2001-05-01

    The spin-glass (SG) transition in Fe(In{sub 2-2x}Cr{sub 2x})S{sub 4} thiospinel with x=0.1 and 0.3 has been studied by susceptibility and Moessbauer measurements. It is found that iron in the system is partially inverted, with {approx}80% high-spin Fe{sup 2+} iron at octahedral sites. AC susceptibility data show a spin-glass-like transition at T{sub SG}=10 K that depends on the driving frequency f, following a Vogel-Fulcher law. Below T{sub SG}, the splitting of Zeeman levels yields a complex Moessbauer spectrum, which was fitted using a full {sup 57}Fe-nuclear Hamiltonian with quadrupolar and magnetic interactions. The reduced magnetic hyperfine field b(T)=B(T)/B{sub S} is well described by a Langevin function L(x), with T{sub C}=12.8(3) K and B{sub S}=16.8(3) T.

  4. Interface study and performance of large layer pair ultra-short period W/B{sub 4}C X-ray multilayer

    Energy Technology Data Exchange (ETDEWEB)

    Pradhan, P. C., E-mail: pcpradhan@rrcat.gov.in; Nayak, M.; Mondal, P.; Lodha, G. S. [Indus Synchrotron Utilization Division, Raja Ramanna Centre for Advanced Technology, Indore-452013 (India)

    2015-06-24

    The nature of interfaces in ultra short period W/B{sub 4}C multilayers (MLs) is studied using hard x-ray reflectivity and cross sectional transmission electron microscope. W/B{sub 4}C MLs are fabricated using magnetron sputtering system with systematic varying thickness of both W and B{sub 4}C layers from ∼5 to 30 Å keeping number of layer pairs fixed at 10. It is observed that in low period W/B{sub 4}C ML, as the layer thickness decreases, the interdiffusion plays a significant role because of the discontinuous nature of film. This gives variation of density and roughness of the layer as well as generates thickness errors in the ML structure due to volume changes which is originated by interdifusion process. Finally, W/B{sub 4}C MLs with large number of layer pairs (300) are fabricated with periodicity d= 20 Å which gives ∼54 % of reflectivity at energy 8.047 keV.

  5. Study of selective heating at ion cyclotron resonance for the plasma separation process

    Energy Technology Data Exchange (ETDEWEB)

    Compant La Fontaine, A. [Direction du Cycle du Combustible/Departement des Procedes d` Enrichissement, Service de Physique, d` Experimentation et d` Analyse, Commissariat a l` Energie Atomique, Centre d` Etudes de Saclay, 91191 Gif-sur-Yvette Cedex (France); Pashkovsky, V.G. [Molecular Physics Institute, RRC Kurchatov Institute 123182, Moscow (Russian Federation)

    1995-12-01

    The plasma separation process by ion cyclotron resonance heating (ICRH) is studied both theoretically and experimentally on two devices: the first one called ERIC (Ion Cyclotron Resonance Experiment) at Saclay (France) [P. Louvet, {ital Proceedings} {ital of} {ital the} 2{ital nd} {ital Workshop} {ital on} {ital Separation} {ital Phenomena} {ital in} {ital Liquids} {ital and} {ital Gases}, Versailles, France, 1989, edited by P. Louvet, P. Noe, and Soubbaramayer (Centre d`Etudes Nucleaires de Saclay and Cite Scientifique Parcs et Technopoles, Ile de France Sud, France, 1989), Vol. 1, p. 5] and the other one named SIRENA at the Kurchatov Institute, Moscow, Russia [A. I. Karchevskii {ital et} {ital al}., Plasma Phys. Rep. {bold 19}, 214 (1993)]. The radio frequency (RF) transversal magnetic field is measured by a magnetic probe both in plasma and vacuum and its Fourier spectrum versus the axial wave number {ital k}{sub {ital z}} is obtained. These results are in agreement with the electromagnetic (EM) field calculation model based on resolution of Maxwell equations by a time-harmonic scheme studied here. Various axial boundary conditions models used to compute the EM field are considered. The RF magnetic field is weakly influenced by the plasma while the electric field components are strongly disturbed due to space-charge effects. In the plasma the transversal electric field is enhanced and the {ital k}{sub {ital z}} spectrum is narrower than in vacuum. The calculation of the resonant isotope heating is made by the Runge--Kutta method. The influence of ion--ion collisions, inhomogeneity of the static magnetic field {ital B}{sub 0}, and the RF transversal magnetic field component on the ion acceleration is examined. These results are successfully compared with experiments of a minor isotope {sup 44}Ca heating measurements, made with an energy analyzer. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  6. A comparative study on the sintering behaviour and phase emergence of calcium borophosphate and calcium titanophosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Arvind, A; Dixit, Anupam; Shrikhande, V K; Kothiyal, G P, E-mail: gpkoth@barc.gov.in [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai-400085 (India)

    2009-07-15

    Calcium-phosphate (CaP) based glasses of composition 60CaO-30P{sub 2}O{sub 5}-10B{sub 2}O{sub 3} (CaPB) and 60CaO-30P{sub 2}O{sub 5}-10TiO{sub 2} (CaPT) with high Ca/P ratio (>1.0) were prepared by quenching the melt into water. The glass frit was crystallized at temperatures in the range of 650-850deg. C and XRD revealed that at 650deg. C, the first phase to form was tetragonal {beta}-Ca{sub 2}P{sub 2}O{sub 7} followed by monoclinic {alpha}-Ca{sub 2}P{sub 2}O{sub 7} at 680deg. C. The addition of TiO{sub 2} or B{sub 2}O{sub 3} did not greatly alter the phase emergence. At the same time, when glass pellets were sintered at 600deg. C, for 2-8 hr, the B{sub 2}O{sub 3} containing samples showed better densification than the TiO{sub 2} containing samples. Incorporation of B{sub 2}O{sub 3} lowers the liquidus temperature and greatly reduces the crystallization tendency. This allows for liquid phase sintering leading to higher densification.

  7. Reflector and Shield Material Properties for Project Prometheus

    Energy Technology Data Exchange (ETDEWEB)

    J. Nash

    2005-11-02

    This letter provides updated reflector and shield preliminary material property information to support reactor design efforts. The information provided herein supersedes the applicable portions of Revision 1 to the Space Power Program Preliminary Reactor Design Basis (Reference (a)). This letter partially answers the request in Reference (b) to provide unirradiated and irradiated material properties for beryllium, beryllium oxide, isotopically enriched boron carbide ({sup 11}B{sub 4}C) and lithium hydride. With the exception of {sup 11}B{sub 4}C, the information is provided in Attachments 1 and 2. At the time of issuance of this document, {sup 11}B{sub 4}C had not been studied.

  8. Bs Mixing at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ceballos, Guillelmo; /Cantabria Inst. of Phys.

    2006-04-01

    The Tevatron collider at Fermilab provides a very rich environment for the study of B{sub s} mesons. B{sub s} Mixing is the most important analysis within the B Physics program of both experiments. In this paper they summarize the most recent results on this topic from both D0 and CDF experiments. There were very important updates in both experiments after his last talk, hence the organizers warmly recommended me to include the latest available results on B{sub s} mixing, instead of what he presents there.

  9. Studies of accelerated compact toruses

    International Nuclear Information System (INIS)

    In an earlier publication we considered acceleration of plasma rings (Compact Torus). Several possible accelerator configurations were suggested and the possibility of focusing the accelerated rings was discussed. In this paper we consider one scheme, acceleration of a ring between coaxial electrodes by a B/sub theta/ field as in a coaxial rail-gun. If the electrodes are conical, a ring accelerated towards the apex of the cone undergoes self-similar compression (focusing) during acceleration. Because the allowable acceleration force, F/sub a/ = kappaU/sub m//R where (kappa -2, the accelerating distance for conical electrodes is considerably shortened over that required for coaxial electrodes. In either case, however, since the accelerating flux can expand as the ring moves, most of the accelerating field energy can be converted into kinetic energy of the ring leading to high efficiency

  10. Iron based pnictide and chalcogenide superconductors studied by muon spin spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Shermadini, Zurab

    2014-07-15

    In the present thesis the superconducting properties of the Iron-based Ba{sub 1-x}Rb{sub x}Fe{sub 2}As{sub 2} arsenides, and A{sub x}Fe{sub 2-y}Se{sub 2} (A=Cs,Rb,K) chalcogenides are investigated by means of Muon Spin Rotation Spectroscopy. The temperature and pressure dependence of the magnetic penetration depth is obtained form μSR experiments and analyzed to probe the superconducting gap-symmetries for each samples. The Ba{sub 1-x}Rb{sub x}Fe{sub 2}As{sub 2} system is described within the multi-gap s+s-wave scenario and results are discussed in the light of the suppression of inter-band processes upon hole doping. Due to the lowered upper critical field B{sub c2} and reduced T{sub c}, a large section of B-T-p phase diagram is studied for the hole-overdoped x=1 case. By applying hydrostatic pressure, the RbFe{sub 2}As{sub 2} system exhibits a classical BCS superconducting characteristics. The A{sub x}Fe{sub 2-y}Se{sub 2} chalcogenide represents a system containing magnetically ordered and superconducting phases simultaneously. In all investigated chalcogenide samples, about 90% of the total volume show the strong antiferromagnetic phase and 10% exhibit a paramagnetic behavior. Magnetization measurements reveal a 100% Meissner effect, while μSR clearly indicates that the paramagnetic phase is a perfect superconductor. Up to now, there is no clear evidence whether the antiferromagnetic phase is also superconducting. The microscopic coexistence and/or phase separation of superconductivity and magnetism is discussed. Moreover, a new hydrostatic double-wall pressure cell is developed and produced, satisfying the demands of μSR experiments. The designs and characteristics of the new pressure cell are reviewed in the present thesis.

  11. A study of the efficiency of different spectrochemical buffers applied to the uranium ore analysis; Estudio de la eficiencia de diversos reguladores espectroqimicos aplicados al analisis de minerales de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Roca, M.; Diaz Guerra, J. P.

    1981-07-01

    A direct-reading emission spectroscopy method allowing the determination of Al, Ca, Fe, Mg, Mn, Na, P, Si and Ti in geological materials, that are of interest for the prospecting and recovery of uranium, is proposed. Direct-current are between graphite electrodes Is used as the excitation source. Efficiency of Ag{sub 2}O, BaCO{sub 3}, Bi{sub 2}O{sub 3}, CuF{sub 2}, CuO, Ga{sub 2}0{sub 3}, Ge0{sub 2}, graphite, K{sub 2}CO{sub 3}, H{sub 2}B{sub 4}O{sub 7}, Li{sub 2}CO{sub 3}, Ni, PbS, Sb{sub 2}o{sub 4} , SrC0{sub 3}, Ti{sub 2}O{sub 3} and ZnO as spectrochemical buffers has been studied. It has been inferred that through a sample dilution with Li{sub 2}CO{sub 3}, SrC0{sub 3} and graphite powder in the rations 1:10:10:20, respectively, the highest reduction of the matrix effects is achieved. Phosphorus determination Is better performed with PbS as spectrochemical buffer Instead of the indicated above. The action of the selected compounds Is completed by using Co, In, Li and Sr as internal standards, and, as a whole, satisfactory accuracy and reproducibility are attained. (Author) 7 refs.

  12. Study of χ{sub b} meson production in pp collisions at √(s) = 7 and 8 TeV and observation of the decay χ{sub b} (3P) → Υ (3S)γ

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela (Spain); Adinolfi, M. [Bristol Univ. (United Kingdom). H.H. Wills Physics Lab.; and others

    2014-10-15

    A study of χ{sub b} meson production at LHCb is performed on proton-proton collision data, corresponding to 3.0 fb{sup -1} of integrated luminosity collected at centre-of-mass energies √(s) = 7 and 8 TeV. The fraction of Υ(nS) mesons originating from χ{sub b} decays is measured as a function of the Υ transverse momentum in the rapidity range 2.0 < y{sup Υ} < 4.5. The radiative transition of the χ{sub b} (3P) meson to Υ(3S) is observed for the first time. The χ{sub b1} (3P) mass is determined to be m{sub χ{sub b{sub 1{sub ({sub 3{sub P{sub )}}}}}}} = 10 511.3 ± 1.7 ± 2.5MeV/c{sup 2}, where the first uncertainty is statistical and the second is systematic. (orig.)

  13. Synchrotron radiation photoelectron studies for primary radiation effects using a liquid water jet in vacuum: Total and partial photoelectron yields for liquid water near the oxygen K-edge

    Energy Technology Data Exchange (ETDEWEB)

    Ukai, Masatoshi [Department of Applied Physics, Tokyo University of Agriculture and Technology, Koganei-shi, Tokyo 184-8588 (Japan)], E-mail: ukai3@cc.tuat.ac.jp; Yokoya, Akinari [Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Nonaka, Yusuke [Department of Applied Physics, Tokyo University of Agriculture and Technology, Koganei-shi, Tokyo 184-8588 (Japan); Fujii, Kentaro [Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Saitoh, Yuji [Synchrotron Radiation Research Center, Japan Atomic Energy Agency (JAEA), Sayo-gun, Hyogo 679-5148 (Japan)

    2009-12-15

    A new spectroscopy to identify the hydration structure playing important role in liquid-phase radiation damage is in progress using a laminar liquid water jet sample in vacuum in combination with soft X-ray synchrotron radiation. We present the total and partial electron yields for liquid water using a photoelectron spectroscopy. Partial electron yields for the K{sup -1}1b{sub 1}1b{sub 1} Auger transition are obtained for the first time by measuring the electrostatically dispersed electron kinetic energy spectra as a function of photon energy of synchrotron radiation.

  14. Structure study and properties of rare earth-rich glassed for the conditioning of nuclear waste; Etude des caracteristiques structurales et des proprietes de verres riches en terres rares destines au confinement des produits de fission et elements a vie longue

    Energy Technology Data Exchange (ETDEWEB)

    Bardez, I

    2004-11-15

    A new nuclear glass composition, able to immobilize highly radioactive liquid wastes from high burn-up UO{sub 2} fuel, was established and its structure studied. The composition of the selected rare earth-rich glass is (molar %): 61.79 SiO{sub 2} - 8.94 B{sub 2}O{sub 3} - 3.05 Al{sub 2}O{sub 3} - 14.41 Na{sub 2}O - 6.32 CaO - 1.89 ZrO{sub 2} - 3.60 RE{sub 2}O{sub 3} (with RE = La, Ce, Pr and Nd) The aim of this study was to determine the local environment of the rare earth in this glass and also to glean information about the effect of glass composition on the rare earth neighbouring (influence of Si, B, Al, Na and Ca contents). To this end, several series of glasses, prepared from the baseline glass, were studied by different characterisation methods such as EXAFS spectroscopy at the neodymium L{sub III}-edge, optical absorption spectroscopy, Raman spectroscopy and {sup 29}Si, {sup 27}Al and {sup 11}B MAS-NMR. By coupling all the results obtained, several hypotheses about the nature of the rare earth neighbouring in the glass were proposed. (author)

  15. Reversed field pinch dynamics and transport studies. Quarterly progress report, 20 July 1983-20 October 1983

    International Nuclear Information System (INIS)

    Progress in RFP dynamics and transport studies is described. The compressible, three-dimensional code SPECTR3 has been modified to include toroidal effects, and classical resistivity and thermal conductivity. Anomalous transport arising from stochastic magnetic fields has been included in the model. These transport effects are treated implicitly. A three-dimensional, incompressible MHD code has been developed. It is computationally more efficient than the existing code, and will be used extensively if compessibility is determined to be unimportant. Post-processor codes to analyze data generated by the nonlinear code have been developed. Three-dimensional computer runs at low THETA (= B/sub theta/(a)/) have found the development of a substantial stochastic core, with good flux surfaces being retained in the outer part of the discharge. Runs at high THETA have shown complete stochasticity, with reappearance of outer flux surfaces as the modes saturate and relax. Anomalous maintenance of positive toroidal flux arising from a poloidal electric field at the field reversal surface induced by MHD fluctuations (dynamo) has been observed. We are collaborating with the ETA-BETA-II experimental group at Padua, Italy, in an attempt to interpret measured internal fluctuations and profiles in terms of resistive MHD. The emphasis of this work is on the effect of MHD fluctuations plasma transport. Analytic studies of the RFP dynamo have begun. We are attempting to find steady state solutions with flow to the resistive MHD equations. A reduced model to simulate phenomena that occur on the relaxation time scale, such as F-THETA current drive, has been formulated

  16. Effects of chlorophyll and chlorophyllin on low-dose aflatoxin B1 pharmacokinetics in human volunteers: A pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Jubert, C; Mata, J; Bench, G; Dashwood, R; Pereira, C; Tracewell, W; Turteltaub, K; Williams, D; Bailey, G

    2009-04-20

    Chlorophyll (Chla) and chlorophyllin (CHL) were shown previously to reduce carcinogen bioavailability, biomarker damage, and tumorigenicity in trout and rats. These findings were partially extended to humans (Proc Natl Acad Sci USA 98, 14601-14606 (2001)), where CHL reduced excretion of aflatoxin B{sub 1} (AFB{sub 1})-DNA repair products in Chinese unavoidably exposed to dietary AFB{sub 1}. However, neither AFB{sub 1} pharmacokinetics nor Chla effects were examined. We conducted a small unblinded crossover study to establish AFB{sub 1} pharmacokinetic parameters in human volunteers, and to explore possible effects of CHL or Chla co-treatment on those parameters. For protocol 1, fasted subjects received an IRB-approved dose of 14C-AFB{sub 1} (30 ng, 5 nCi) by capsule with 100 ml water, followed by normal eating and drinking after hr 2. Blood and cumulative urine samples were collected over 72 hr, and {sup 14}C-AFB{sub 1} equivalents were determined by Accelerator Mass Spectrometry. Protocols 2 and 3 were similar except capsules also contained 150 mg of purified Chla, or CHL, respectively. All protocols were repeated 3 times for each of three volunteers. The study revealed rapid human AFB{sub 1} uptake (plasma ka 5.05 {+-} 1.10 hr-1, Tmax 1.0 hr) and urinary elimination (95% complete by 24 hr) kinetics. Chla and CHL treatment each significantly impeded AFB{sub 1} absorption and reduced Cmax and AUC's (plasma and urine) in one or more subjects. These initial results provide AFB{sub 1} pharmacokinetic parameters previously unavailable for humans, and suggest that Chla or CHL co-consumption may limit the bioavailability of ingested aflatoxin in humans, as they do in animal models.

  17. Thulium-170 oxide heat source experimental and analytical radiation and shielding study

    International Nuclear Information System (INIS)

    Radiation dose rates from three thulium-170 oxide sources (20.7, 10.0 and 5.0 thermal watts) were measured through three thicknesses (1/4, 1/2 and 1 inch) of absorber by thermoluminescent dosimetry techniques. Absorber materials used were aluminium, stainless steel, lead, tungsten and depleted uranium. Resultant radiation doses were measured at 19 and 100 cm. Comparison of theoretical dose rates calculated by computer with measured dose rates validated the calculation technique for lead, tungsten and uranium absorbers but not for aluminum and stainless steel. Use of infinite medium build-up factors (B/sub ∞/) was thus validated in computation of dose rates for lead, tungsten and uranium absorbers; use of B/sub ∞/ in computation of dose rates for aluminum and stainless steel absorbers overestimated dose rates vis-a-vis experimentally determined dose rates by an approximate factor of 2

  18. Use of Li.sub.2[B.sub.12H.sub.12] salt to absorb water into polymers

    Energy Technology Data Exchange (ETDEWEB)

    Eastwood, Eric A.; Bowen, III, Daniel E.

    2016-08-30

    Methods of adjusting the properties of a composition are provided. The compositions comprise a polymer-containing matrix and a filler comprising a hygroscopic salt. Preferred such salts comprise a cage compound selected from the group consisting of borane cage compounds, carborane cage compounds, metal complexes thereof, residues thereof, mixtures thereof, and/or agglomerations thereof, where the cage compound is not covalently bound to the matrix polymer.

  19. Effect of the inclusion of adsorbents on aflatoxin B>1 quantification in animal feedstuffs

    OpenAIRE

    Gallo, Antonio; Masoero, Francesco; Bertuzzi, Terenzio; Piva, Gianfranco; Pietri, Amedeo

    2009-01-01

    Abstract The extraction efficiency of aflatoxin B1 (AFB1) in cattle feeds containing 9 adsorbents (ADSs), was investigated using two organic/aqueous solvents, composed of methanol/water (80/20 v/v; MeOH) and acetone/water (85/15 v/v; AC). Feed samples were obtained including in a high (HC) and a low (LC) AFB1 contaminated feedstuffs (15.33 and 7.57 ?g kg-1, respectively), nine ADSs (4 clay minerals; 1 yeast cell wall-based product; 1 activated carbon and 3 commercial ADS products) ...

  20. $B$ mixing and lifetimes at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ceballos, G.; Piedra, J.

    2006-04-01

    The Tevatron collider at Fermilab provides a very rich environment for the study of b-hadrons. Both the D0 and CDF experiments have collected a sample of about 1 fb{sup -1}. they report results on three topics: b-hadron lifetimes, polarization amplitudes and the decay width difference in B{sub s}{sup 0} {yields} J/{psi}{phi}, and B{sub s}{sup 0} mixing.

  1. Polarization-dependent X-ray-absorption spectroscopy of $RNi_{2} B_{2}$ C (R=Er $\\to$ Lu) Reduced Ni-3d occupancy in $YbNi_{2} B_{2} C$

    CERN Document Server

    Mazumdar, C; Von Lips, H; Golden, M S; Fink, J; Canfield, P C; Kaindl, G

    2001-01-01

    We present here the results of polarization-dependent X-ray- absorption near-edge structure (XANES) studies at the B-K, C-K, and Ni-L/sub 3/ thresholds of single-crystalline borocarbide compounds RNi/sub 2/B/sub 2/C (with R=Er to Lu) using bulk-sensitive fluorescence yield technique. The Ni-L/sub 3/ XANES spectrum for YbNi /sub 2/B/sub 2/C with photon polarization parallel to the ab plane is significantly more intense than in analogous spectra of other members of this series. This indicates a reduced Ni-3d occupancy in the Ni /sub 2/B/sub 2/ layer in YbNi/sub 2/B/sub 2/C, a fact that might be responsible for the absence of superconductivity in this material. (26 refs).

  2. The diffraction pattern of pp elastic scattering and the composite structure of the proton

    CERN Document Server

    Van Hove, Léon Charles Prudent

    1977-01-01

    The consequences of the quark-glue structure of hadrons for pp elastic scattering are examined in a simple model where the glue is taken to be the active constituent in normal (low p/sub T/) hadronic collisions. Earlier work based on the study of pp inelastic diffraction concluded that the glue-glue elastic amplitude t/sub g/ is approximately Gaussian in the glue-glue impact parameter b/sub g/, with maximum opacity at b/sub g/=0. A slight refinement of this approximation, in which t/sub g/ is almost maximally opaque over a small b/sub g/ interval and is Gaussian at larger b/sub g/, is shown to account for the remarkable diffraction structure observed in pp elastic scattering at ISR energies. A simple form is obtained for the form factor describing the impact parameter distribution of the glue inside a proton. (8 refs).

  3. Priority compositions of boron carbide crystals obtained by self-propagating high-temperature synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Ponomarev, V. I., E-mail: ksv17@ism.ac.ru; Konovalikhin, S. V.; Kovalev, I. D.; Vershinnikov, V. I. [Russian Academy of Sciences, Institute of Structural Macrokinetics and Materials Science (Russian Federation)

    2015-09-15

    Splitting of reflections from boron carbide has been found for the first time by an X-ray diffraction study of polycrystalline mixture of boron carbide B{sub 15–x}C{sub x}, (1.5 ≤ x ≤ 3) and its magnesium derivative C{sub 4}B{sub 25}Mg{sub 1.42}. An analysis of reflection profiles shows that this splitting is due to the presence of boron carbide phases of different compositions in the sample, which are formed during crystal growth. The composition changes from B{sub 12.9}C{sub 2.1} to B{sub 12.4}C{sub 2.6}.

  4. B-meson spectroscopy in HQET at order 1/m

    Energy Technology Data Exchange (ETDEWEB)

    Bernardoni, Fabio [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Technische Univ. Dresden (Germany). Medizinische Fakultaet ' ' Carl Gustav Carus' ' ; Blossier, Benoit [Paris XI Univ. (France). Laboratoire de Physique Theorique; Bulava, John; Garron, Nicolas [Plymouth Univ. (United Kingdom). School of Computing and Mathematics; Della Morte, Michele [Univ. of Southern Denmark, Odense (Denmark). CP3-Origins; Univ. of Southern Denmark, Odense (Denmark). Danish IAS; Instituto de Fisica Corpuscular, Valencia (Spain); CSIC, Valencia (Spain); Fritsch, Patrick [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Univ. Autonoma de Madrid (Spain). Inst. de Fisica Teorica UAM/CSIC; Gerardin, Antoine [Paris XI Univ. (France). Laboratoire de Physique Theorique; Univ. Blaise Pascal CNRS/IN2P3, Aubiere (France). Laboratoire de Physique Corpusculaire; Heitger, Jochen [Muenster Univ. (Germany). Inst. fuer Theoretische Physik 1; Hippel, Georg von [Mainz Univ. (Germany). Inst. fuer Kernphysik; Simma, Hubert [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Collaboration: Alpha Collaboration

    2015-05-15

    We present a study of the B spectrum performed in the framework of Heavy Quark Effective Theory expanded to next-to-leading order in 1/m{sub b} and non-perturbative in the strong coupling. Our analyses have been performed on N{sub f}=2 lattice gauge field ensembles corresponding to three different lattice spacings and a wide range of pion masses. We obtain the B{sub s}-meson mass and hyperfine splittings of the B- and B{sub s}-mesons that are in good agreement with the experimental values and examine the mass difference m{sub B{sub s}}-m{sub B} as a further cross-check of our previous estimate of the b-quark mass. We also report on the mass splitting between the first excited state and the ground state in the B and B{sub s} systems.

  5. On current termination in rotamak discharges

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, N.; Euripides, P.; Jones, I.R.; Xu, S. [Flinders Univ. of South Australia, Bedford Park, SA (Australia). School of Physical Sciences

    1995-03-01

    A new series of rotamak experiments conducted in a 50 litre spherical pyrex discharge vessel is described. An analysis of the results, together with that of previous results from a smaller, 10 litre vessel, provides an explanation for the current termination phenomenon which is such a noteworthy and characteristic feature of all rotamak discharges studied to date. It is shown that the amplitude of the applied rotating magnetic field, B{sub {omega}}, has to be greater than a certain critical value, B{sub {omega}}{sup crit}, for the rotamak discharge to be maintained. Provided B{sub {omega}} {>=} B{sub {omega}}{sup crit}, the properties of the discharge are then determined by the behaviour of the circuit used to couple the RF generators to the plasma load. The conditions necessary for the production of a compact toroidal magnetic configuration are presented. (author).

  6. Structural and optical studies of FeSb{sub 2} under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Poffo, C.M.; Souza, S.M.; Triches, D.M. [Departamento de Engenharia Mecanica, Universidade Federal de Santa Catarina, Campus Universitario Trindade, S/N, C.P. 476, 88040-900 Florianopolis, Santa Catarina (Brazil); Lima, J.C. de, E-mail: fsc1jcd@fisica.ufsc.br [Departamento de Fisica, Universidade Federal de Santa Catarina, Campus Universitario Trindade, S/N, C.P. 476, 88040-900 Florianopolis, Santa Catarina (Brazil); Grandi, T.A. [Departamento de Fisica, Universidade Federal de Santa Catarina, Campus Universitario Trindade, S/N, C.P. 476, 88040-900 Florianopolis, Santa Catarina (Brazil); Polian, A.; Gauthier, M. [Physique des Milieux Denses, IMPMC, CNRS-UMR 7590, Universite Pierre et Marie Curie-Paris 6, B115, 4 Place Jussieu, 75252 Paris Cedex 05 (France)

    2012-12-15

    Nanostructured orthorhombic FeSb{sub 2} was formed along with an amorphous phase, by mechanical alloying from a mixture of Fe and Sb powders. The influence of pressure on the structural and optical properties of the material was investigated by X-ray diffraction (XRD) and Raman spectroscopy (RS) up to 28.2 and 45.2 GPa, respectively. The volume fraction of the amorphous phase increased with increasing pressure. For pressures above 14.3 GPa, a tetragonal FeSb{sub 2} phase was also observed. For the orthorhombic FeSb{sub 2} phase, the pressure dependence of the volume fitted to a Birch-Murnaghan equation of state gave a bulk modulus B{sub 0}=75.5{+-}3.2 GPa, and its derivative B{sub 0}{sup Prime }=7.2{+-}0.7. For the orthorhombic FeSb{sub 2} phase, the Raman active A{sub g}{sup 2} mode was observed up to 28.3 GPa, while the B{sub 1g}{sup 2} mode was not for pressures larger than 14 GPa. For pressures above 21 GPa, the Raman active A{sub 1g} mode of a tetragonal FeSb{sub 2} phase was observed.

  7. Beautiful CP violation

    Energy Technology Data Exchange (ETDEWEB)

    Dunietz, I. [Fermi National Accelerator Lab., Batavia, IL (United States)

    1998-05-01

    CP violation is observed to date only in K{sup 0} decays and is parameterizable by a single quantity {epsilon}. Because it is one of the least understood phenomena in the standard model and holds a clue to baryogenesis, it must be investigated further. Highly specialized searches in K{sup 0} decays are possible. Effects in B decays are much larger. In addition to the traditional B{sub d}{yields}J/{psi}K{sub S}, {pi}{sup +}{pi}{sup -} asymmetries, CP violation could be searched for in already existing inclusive B data samples. The rapid B{sub s}- anti B{sub s} oscillations cancel in untagged B{sub s} data samples, which therefore allow feasibility studies for the observation of CP violation and the extraction of CKM elements with present vertex detectors. The favored method for the extraction of the CKM angle {gamma} is shown to be unfeasible and a solution is presented involving striking direct CP violation in charged B decays. Novel methods for determining the B{sub s} mixing parameter {Delta}m are described without the traditional requirement of flavor-specific final states. The CKM phase {phi}=-2{beta}-{gamma}=-{pi}+{alpha}-{beta} can be obtained from time-dependent studies of B{sub d}(t){yields}D{sup (*){+-}}{pi}{sup -+}, even in the presence of possible final-state interactions. (orig.) 42 refs.

  8. The Electrochemical Behavior of Ni-base Metallic Glasses Containing Cr in H{sub 2}SO{sub 4} Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Arab, Sanaa T. [Taibaj Univ., Madina (Saudi Arabia); Emran, Khadijah M. [King Abdulaziz Univ., Jeddah (Saudi Arabia); Alturaif, Hamad A. [King Abdulaziz Univ., Jeddah (Saudi Arabia)

    2012-08-15

    In order to develop alloy resistance in aggressive sulphat ion, the corrosion behavior of metallic glasses Ni{sub 92.3}Si{sub 4.5}B{sub 32}, Ni{sub 82,3}Cr{sub 7}Fe{sub 3}Si{sub 4.5}B{sub 3.2} and Ni{sub 75.5}Cr{sub 13}Fe{sub 4.2}Si{sub 4.5}B{sub 2.8} (at %) at different concentrations of H{sub 2}SO{sub 4} solutions was examined by electrochemical methods and Scanning Electron Microscope (SEM) and X-ray Photoelectron Microscopy (XPS) analyses. The corrosion kinetics and passivation behavior was studied. A direct proportion was observed between the corrosion rate and acid concentration in the case of Ni{sub 92.3}Si{sub 4.5}B{sub 32} and Ni{sub 75.5}Cr{sub 13}Fe{sub 4.2}Si{sub 4.5}B{sub 2.8} alloys. Critical concentration was observed in the case of Ni{sub 82,3}Cr{sub 7}Fe{sub 3}Si{sub 4.5}B{sub 3.2} alloy. The influence of the alloying element is reflected in the increasing resistance of the protective film. XPS analysis confirms that the protection film on the Ni{sub 92.3}Si{sub 4.5}B{sub 32} alloy was NiS which is less protective than that formed on Cr containing alloys. The corrosion rate of Ni{sub 82,3}Cr{sub 7}Fe{sub 3}Si{sub 4.5}B{sub 3.2} and Ni{sub 75.5}Cr{sub 13}Fe{sub 4.2}Si{sub 4.5}B{sub 2.8}. alloys containing 7% and 13% Cr are 7.90-26.1Χ10{sup -3} mm/y which is lower about 43-54 times of the alloy Ni{sub 92.3}Si{sub 4.5}B{sub 32} (free of Cr). The high resistance of Ni{sub 75.5}Cr{sub 13}Fe{sub 4.2}Si{sub 4.5}B{sub 2.8} alloy at the very aggressive media may due to thicker passive film of Cr{sub 2}O{sub 3} which hydrated to hydrated chromium oxyhydroxide.

  9. Some heavy vector and tensor meson decay constants in light-front quark model

    Energy Technology Data Exchange (ETDEWEB)

    Geng, Chao-Qiang [Chongqing Jiaotong University, College of Materials Science and Engineering, Chongqing (China); National Tsing Hua University, Department of Physics, Hsinchu (China); National Center for Theoretical Sciences, Physics Division, Hsinchu (China); Lih, Chong-Chung [National Center for Theoretical Sciences, Physics Division, Hsinchu (China); Shu-Zen College of Medicine and Management, Department of Optometry, Kaohsiung Hsien (China); Xia, Chuanhui [Chongqing Jiaotong University, College of Materials Science and Engineering, Chongqing (China)

    2016-06-15

    We study the decay constants (f{sub M}) of the heavy vector (D{sup *}, D{sub s}{sup *}, B{sup *}, B{sub s}{sup *}, B{sub c}{sup *}) and tensor (D{sub 2}{sup *}, D{sub s2}{sup *}, B{sub 2}{sup *}, B{sub s2}{sup *}) mesons in the light-front quarkmodel.With the known pseudoscalar meson decay constants of f{sub D}, f{sub Ds}, f{sub B}, f{sub Bs}, and f{sub Bc} as the input parameters to determine the light-front meson wave functions, we obtain f{sub D{sup *},D{sub s{sup *}B{sup *}B{sub s{sup *},B{sub c{sup *}}}}} = (252.0{sub -11.6}{sup +13.8}, 318.3{sub -12.6}{sup +15.3}, 201.9{sub -41.4}{sup +43.2}, 244.2 ± 7.0, 473.4 ± 18.2) and (264.9{sub -9.5}{sup +10.2}, 330.9{sub -9.0}{sup +9.9}, 220.2{sub -46.2}{sup +49.1}, 265.7 ± 8.0, 487.6 ± 19.2) MeV with Gaussian and power-law wave functions, respectively, while we have f{sub D{sub 2{sup *},D{sub s{sub 2{sup *}B{sub 2{sup *}B{sub s{sub 2{sup *}}}}}}}} = (143.6{sub -21.8}{sup +24.9}, 209.5{sub -24.2}{sup +29.1}, 80.9{sub -27.7}{sup +33.8}, 109.7{sub -15.0}{sup +15.7}) MeV with only Gaussian wave functions. (orig.)

  10. Effect of addition of tartaric acid on synthesis of boron carbide powder from condensed boric acid–glycerin product

    Energy Technology Data Exchange (ETDEWEB)

    Tahara, Naoki; Kakiage, Masaki, E-mail: kakiage@apc.saitama-u.ac.jp; Yanase, Ikuo; Kobayashi, Hidehiko

    2013-10-05

    Highlights: •B{sub 4}C powder was synthesized from a condensed H{sub 3}BO{sub 3}-glycerin product with tartaric acid added. •A precursor consisting of B{sub 2}O{sub 3} and carbon was prepared by the thermal decomposition in air. •The precursors had a three-dimensional bicontinuous B{sub 2}O{sub 3}/carbon network structure. •The dispersion state became more homogeneous and finer with the addition of tartaric acid. •The complete formation of B{sub 4}C powder was achieved at 1250 °C within a shorter heat treatment time. -- Abstract: The effect of the addition of tartaric acid on the synthesis of boron carbide (B{sub 4}C) powder from a condensed boric acid (H{sub 3}BO{sub 3})–glycerin product was investigated in this study. The condensed product was prepared by dehydration condensation after directly mixing equimolar amounts of H{sub 3}BO{sub 3} and glycerin with the addition of 0–50 mol% tartaric acid (based on glycerin), which was followed by thermal decomposition in air to obtain a precursor powder from which excess carbon had been eliminated. The dispersion state of the boron oxide (B{sub 2}O{sub 3}) and carbon components in the precursor prepared from the condensed product with 25 mol% tartaric acid added was finer than that without tartaric acid added, in which both precursors had a three-dimensional bicontinuous B{sub 2}O{sub 3}/carbon network structure. The complete formation of crystalline B{sub 4}C powder was achieved at 1250 °C within a shorter heat treatment time for the precursor with a fine dispersion state. The synthesized B{sub 4}C powders became fine owing to the increased number of nucleation sites.

  11. Developement of a same-side kaon tagging algorithm of B^0_s decays for measuring delta m_s at CDF II

    Energy Technology Data Exchange (ETDEWEB)

    Menzemer, Stephanie; /Heidelberg U.

    2006-06-01

    The authors developed a Same-Side Kaon Tagging algorithm to determine the production flavor of B{sub s}{sup 0} mesons. Until the B{sub s}{sup 0} mixing frequency is clearly observed the performance of the Same-Side Kaon Tagging algorithm can not be measured on data but has to be determined on Monte Carlo simulation. Data and Monte Carlo agreement has been evaluated for both the B{sub s}{sup 0} and the high statistics B{sup +} and B{sup 0} modes. Extensive systematic studies were performed to quantify potential discrepancies between data and Monte Carlo. The final optimized tagging algorithm exploits the particle identification capability of the CDF II detector. it achieves a tagging performance of {epsilon}D{sup 2} = 4.0{sub -1.2}{sup +0.9} on the B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +} sample. The Same-Side Kaon Tagging algorithm presented here has been applied to the ongoing B{sub s}{sup 0} mixing analysis, and has provided a factor of 3-4 increase in the effective statistical size of the sample. This improvement results in the first direct measurement of the B{sub s}{sup 0} mixing frequency.

  12. Corrosion study of Fe-based bulk metallic glasses in chloride medium

    International Nuclear Information System (INIS)

    Bulk metallic glasses (amorphous metals) are an emerging class of alloys due to their unique set of properties. They exhibit excellent mechanical strength, high hardness and corrosion resistance. Unlike other new materials, which are developed to fulfill a particular need, BMGs came to existence without any application, so the uses of BMGs are yet to be exploited. Before putting BMGs into applications, their properties must be fully understood, particularly the corrosion resistance against a working environment. Fe-based amorphous alloys are particularly important for their future use as structural materials due to their high strength and cheap raw materials. Some Fe-based amorphous alloys exhibit excellent soft magnetic properties, which make them feasible to be used as transformer materials. Some compositions are also competitive to replace the existing bio-materials like 316L SS due to their better biocompatibility. Fe-based amorphous alloys can also be used as thermal-spray coatings due to their unchanged corrosion resistance as compared to bulk alloy. Many electrochemical studies have been done to investigate the corrosion resistance of Fe- based BMG that showed its excellent corrosion resistance. Still not enough data is available and further work is needed to be done in this field. In the present study, corrosion of Fe/sub 50/Cr/sub 14/Mo/sub 14/C/sub 14/B/sub 6/X/sub 2/ (X = Y, Gd, and Dy), designated as S1, S2 and S3 respectively, was investigated in 4M NaCI solution. The corrosion study was done using potentiodynamic polarization test and accelerated corrosion test at a current density of 6mA.cm/sup -2/. Following this; corrosion morphology was investigated by scanning electron microscope, while compositional analysis was done by energy dispersive x-ray spectroscope (EDX) attached with SEM. S1 and S3 showed similar corrosion behavior with S3 having the highest corrosion resistance while S2 have different corrosion behavior as well as least corrosion

  13. Study the influence of zinc oxide addition on cobalt doped alkaline earth borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, F., E-mail: F.Ahmad378@yahoo.com [Department of Physics, Faculty of Science, Alazhar University (Girls Branch), Nasr City, Cairo (Egypt); Hassan Aly, E. [Department of Physics, Faculty of Science, Ain Shams University, P.O. Box 11566, Abbassia, Cairo (Egypt); Atef, M.; ElOkr, M.M. [Department of Physics, Faculty of Science, Alazhar University, Nasr City, Cairo (Egypt)

    2014-04-01

    Highlights: • The glassy system xZnO–(79.9−x)B{sub 2}O{sub 3}–20BaO–0.1Co{sub 3}O{sub 4} was prepared by a quenching method. • XRD patterns revealed that the amorphous nature of the present glasses matrix. • The results show that Zn{sup 2+} ions occupy both forming and modifying positions. • Optical parameters are reported as a function of ZnO content. - Abstract: The glasses of the composition 79.9B{sub 2}O{sub 3}–20BaO–0.1Co{sub 3}O{sub 4} doped with different concentrations of ZnO (5, 10, 15, 20, 25 and 30 mol%) were prepared using melt quenching technique. Various studies such as XRD, density, theoretical optical basicity, FT-IR and optical absorption have been carried out to study the role of ZnO on the physical and structural properties of the investigated system. Powder X-ray diffraction patterns confirmed the glassy nature of all the glassy samples. The density and molar volume of glassy samples showed opposite behavior to each other. An increment of the theoretical optical basicity with increasing ZnO content, which is due to an increase in the polarizability and a decrease in the single bond strength is observed. FT-IR analysis revealed that an increase in non-bridging oxygen’s (NBO’s) up to ZnO ⩽ 15 mol% and then a decrease at ZnO > 15 mol%. The results indicated that the Zn{sup 2+} ions are likely to occupy network modifier positions at a concentration of ZnO ⩽ 15 mol%. Above which these ions occupy network forming positions. From ultraviolet absorption edges calculations, the optical band gap energy and steepness parameter decrease whilst Urbach energy and refractive index increase by the addition of ZnO up to 15 mol% above which then the behavior follows reversal trend. The values of the crystal field strength and the interelectronic repulsion Racah parameter calculated from the optical transitions energies of cobalt doped glassy samples. All prepared samples exhibit blue color, indicating that mostly Co ions are acted upon

  14. Studies on contamination level of aflatoxins in Pakistani rice

    International Nuclear Information System (INIS)

    Aflatoxins (AF) are highly toxic and carcinogenic secondary fungal metabolites and have been detected in various food commodities including cereals. Rice samples collected during 2008-2009 were analyzed for aflatoxin B/sub 1/ (AFB/sub 1/), aflatoxin B/sub 2/ (AFB/sub 2/), aflatoxin G/sub 1/ (AFG/sub 1/) and aflatoxin G/sub 2/ (AFG/sub 2/) by thin layer chromatographic (TLC) technique. In total, 40 rice samples were collected and after dividing samples to sub-samples, AF analyses were carried out. AFB/sub 1/ was detected in 28 samples (70 % of the total). The mean of AFB/sub 1/ was 3.7 ng/g for all samples. Total AF (AFT) was detected in 28 samples (70 % of the total). The mean of AFT was 4.9 ng/g for all samples. AFB/sub 1/ levels in 20 samples were below the maximum tolerated level (MTL) of AFB/sub 1/ (2 ng/g). Regarding AFT, the mean contamination level (4.9 ng/g) was higher than the EU maximum permissible level for AFT (4 ng/g). (author)

  15. Electron microscopy study of direct laser deposited IN718

    Energy Technology Data Exchange (ETDEWEB)

    Ding, R.G., E-mail: r.ding@bham.ac.uk [School of Metallurgy and Materials, The University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Huang, Z.W.; Li, H.Y. [School of Metallurgy and Materials, The University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Mitchell, I.; Baxter, G. [Rolls-Royce plc., Derby DE24 8BJ (United Kingdom); Bowen, P. [School of Metallurgy and Materials, The University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2015-08-15

    The microstructure of direct laser deposited (DLD) IN718 has been investigated in detail using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results confirm that the dendrite core microstructure can be linked to the cooling rate experienced during the deposition. A ~ 100 μm wide δ partially dissolved region in the IN718 substrate was observed close to the substrate/deposit boundary. In the deposited IN718, γ/Laves eutectic constituent is the predominant minor microconstituent. Irregular and regular (small) (Nb,Ti)C carbides and a mixture of the carbides and Laves were observed. Most M{sub 3}B{sub 2} borides were nucleated around a (Nb,Ti)C carbide. Needles of δ phase precipitated from the Laves phase were also observed. A complex constituent (of Laves, δ, α-Cr, γ″, and γ matrix) is reported in IN718 for the first time. The formation of α-Cr particles could be related to Cr rejection during the formation and growth of Cr-depleted δ phase. - Highlights: • Secondary phases in IN718 deposits were identified using electron diffraction and EDS. • MC, M{sub 3}B{sub 2}, γ/Laves eutectic and γ/NbC/Laves eutectic were observed. • Needle-like δ phases were precipitated from the Laves phase. • A complex constituent (Laves, δ, α-Cr, γ″ and γ) was reported for the first time.

  16. Effect of Mg/B{sub 2}O{sub 3} molar ratio and furnace temperature on the phase evaluation and morphology of SiC–B{sub 4}C nanocomposite prepared by MASHS method

    Energy Technology Data Exchange (ETDEWEB)

    Roghani, Hamed [Semiconductor Department, Materials and Energy Research Center, Karaj (Iran, Islamic Republic of); Tayebifard, Seyed Ali, E-mail: a_tayebifard@yahoo.com [Semiconductor Department, Materials and Energy Research Center, Karaj (Iran, Islamic Republic of); Kazemzadeh, Asghar [Semiconductor Department, Materials and Energy Research Center, Karaj (Iran, Islamic Republic of); Nikzad, Leila [Ceramic Department, Materials and Energy Research Center, Karaj (Iran, Islamic Republic of)

    2015-07-01

    In this study, SiC–B{sub 4}C nanocomposite has been synthesized in situ successfully by Mechanical activated combustion synthesis method (MASHS). Initially Si, C, B{sub 2}O{sub 3} and Mg powders as raw materials were weighed according to different molar ratio of Mg to B{sub 2}O{sub 3}. In next step theses materials were milled in a planetary mill under Ar atmosphere. The synthesis step was performed in a tube furnace equipped with controlled atmosphere system. The different furnace temperature was investigated on the phase synthesis and morphology of the products. The specimens in the various steps were studied by XRD analysis for evaluation of the phase compositions and calculation of the average crystallite size of them. The morphology of synthesized products was investigated by scanning and transmission electron microscopes (SEM&TEM). The final product contains main phases MgO, B{sub 4}C and SiC. Also, In this sample byproducts were characterized such as Mg{sub 3}B{sub 2}O{sub 6}, Mg{sub 2}B{sub 2}O{sub 5} and remaining carbon. XRD pattern of synthesized sample showed the considerable effect of increasing Mg to B{sub 2}O{sub 3} molar ratio on reducing the amount of Mg{sub 3}B{sub 2}O{sub 6}, Mg{sub 2}B{sub 2}O{sub 5} and remaining carbon. SiC–B{sub 4}C composite was synthesized with more homogenous morphology by reducing the furnace temperature from 1000 to 900 °C, but reduction of temperature up to 800 °C give rise to uncompleted reaction whereas some unreacted Si remains. Average crystallite sizes of optimal sample were calculated 10.5 and 8 nm for SiC and B{sub 4}C respectively. These values are consisted of the TEM results somehow while grain size was less than 70 nm. Also SEM observation showed fine grains with sizes falling in the nanometer range. - Graphical abstract: Display Omitted - Highlights: • Composite prepared by combustion synthesis method in system of Si, C, B{sub 2}O{sub 3} and Mg. • More than stoichiometric Mg/B{sub 2}O{sub 3

  17. Study of crotoxin mechanism of action to mammary carcinomas and evaluation of its potential as a radiopharmaceutical; Estudo do mecanismo de acao da crotoxina em tumores mamarios e avaliacao do seu potenctial radiofarmaceutico

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Marina Bicalho

    2010-07-01

    Crotoxin, the main component of Crotalus durissus terrificus snake venom, has been studied since 1938. It is a natural polypeptidic complex with pharmacological potential because of its antitumoral properties which has attracted great interest for diagnosis and therapy of oncological diseases. However, Crotoxin mechanism of action and sites of specific interaction on tumor cells are still misunderstood. Breast cancer is the second most frequent type in the world and the most common cancer in women. About 30 to 60% of mammary tumors overexpress epidermal growth factor receptor (EGFR), a transmembrane protein related to cell proliferation. Since literature has reported that Crotoxin antitumoral effect is more potent on cells with EGFR overexpression the objectives of this work were to evaluate Crotoxin cytotoxic effects on mammary tumor cells human breast carcinoma (MCF-7) and Ehrlich tumor cells (murine ascitics carcinoma), and to investigate the specific molecular interaction of Crotoxin on Ehrlich tumor cells. Initially, Crotoxin was radiolabelled with iodine-125 ({sup 125}I-Crotoxin) and iodine-131 ({sup 131}I-Crotoxin). Saturation and competition assay were carried out to characterize Crotoxin in vitro interaction; Crotoxin biodistribution studies and singlephoton emission computed tomography (SPECT) of mice bearing Ehrlich tumor have been evaluated to describe in vivo interaction. Our results showed that Crotoxin presented cytotoxic effect against Ehrlich with DL{sub 50} in vitro (concentration of compound which is lethal for 50% of cells) of about one micromolar, but did not present significant effect against MCF-7. Morphological alterations characteristic of apoptosis suggests programmed cell death. {sup 125}I-Crotoxin interaction with Ehrlich tumor cells was saturable with approximately 70% specificity, and presented K{sub d}=24.98 nmol/L and B{sub max}=16,570 sites/cell for low affinity binding sites and K{sub d}=0.06 nmol/L and B{sub max}=210 sites

  18. Core-level photoabsorption study of defects and metastable bonding configurations in boron nitride

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, I.; Jankowski, A.F.; Terminello, L.J. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    Boron nitride is an interesting material for technological applications and for fundamental solid state physics investigations. It is a compound isoelectronic with carbon and, like carbon can possess sp{sup 2} and sp{sup 3} bonded phases resembling graphite and diamond. BN crystallizes in the sp{sup 2}-bonded hexagonal (h-BN), rhombohedral (r-BN) and turbostratic phases, and in the sp{sup 3}-bonded cubic (c-BN) and wurtzite (w-BN) phases. A new family of materials is obtained when replacing C-C pairs in graphite with isoelectronic B-N pairs, resulting in C{sub 2}BN compounds. Regarding other boron compounds, BN is exceptional in the sense that it has standard two-center bonds with conventional coordination numbers, while other boron compounds (e.g. B{sub 4}C) are based on the boron icosahedron unit with three-center bonds and high coordination numbers. The existence of several allotropic forms and fullerene-like structures for BN suggests a rich variety of local bonding and poses the questions of how this affects the local electronic structure and how the material accommodates the stress induced in the transition regions between different phases. One would expect point defects to play a crucial role in stress accommodation, but these must also have a strong influence in the electronic structure, since the B-N bond is polar and a point defect will thus be a charged structure. The study of point defects in relationship to the electronic structure is of fundamental interest in these materials. Recently, the authors have shown that Near-Edge X-ray Absorption Fine Structure (NEXAFS) is sensitive to point defects in h-BN, and to the formation of metastable phases even in amorphous materials. This is significant since other phase identification techniques like vibrational spectroscopies or x-ray diffraction yield ambiguous results for nanocrystalline and amorphous samples. Serendipitously, NEXAFS also combines chemical selectivity with point defect sensitivity.

  19. Study of the effect of boron doping on the solid phase crystallisation of hydrogenated amorphous silicon films

    Energy Technology Data Exchange (ETDEWEB)

    Westra, J.M.; Swaaij, R.A.C.M.M. van [Photovoltaic Materials and Devices, Department of Sustainable Electrical Energy, Delft University of Technology, Delft (Netherlands); Šutta, P. [New Technologies-Research Centre, University of West Bohemia, Plzen (Czech Republic); Sharma, K.; Creatore, M. [Department of Applied Physics, Eindhoven University of Technology, Eindhoven (Netherlands); Zeman, M. [Photovoltaic Materials and Devices, Department of Sustainable Electrical Energy, Delft University of Technology, Delft (Netherlands)

    2014-10-01

    Thin-film polycrystalline silicon on glass obtained by crystallization of hydrogenated amorphous silicon (a-Si:H) films is an interesting alternative for thin-film silicon solar cells. Although the solar-cell efficiencies are still limited, this technique offers excellent opportunity to study the influence of B-doping on the crystallisation process of a-Si:H. Our approach is to slowly crystallize B-doped a-Si:H films by solid phase crystallization in the temperature range 580–600°C. We use plasma-enhanced chemical vapour deposition (PECVD) and expanding thermal plasma chemical vapour deposition (ETPCVD) for the B-doped a-Si:H deposition. In this work we show the first in-situ study of the crystallization process of B-doped a-Si:H films produced by ETPCVD and make a comparison to the crystallization of intrinsic ETPCVD deposited a-Si:H as well as intrinsic and B-doped a-Si:H films deposited by PECVD. The crystallization process is investigated by in-situ x-ray diffraction, using a high temperature chamber for the annealing procedure. The study shows a strong decrease in the time required for full crystallisation for B-doped a-Si:H films compared to the intrinsic films. The time before the onset of crystallisation is reduced by the incorporation of B as is the grain growth velocity. The time to full crystallisation can be manipulated by the B{sub 2}H{sub 6}-to-SiH{sub 4} ratio used during the deposition and by the microstructure of the as-deposited a-Si:H films. - Highlights: • Solid-phase crystallization of B-doped a-Si:H films is presented. • Crystallization study of B-doped and intrinsic a-Si:H by in-situ x-ray diffraction • The microstructure and B-doping of a-Si:H influences the crystallisation process. • B enhances the grain growth rate, but the effect on the nucleation rate is limited.

  20. Control of crystallization kinetics and study of the thermal, structural and morphological properties of an Li{sub 2}O-B{sub 2}O{sub 3}-Al{sub 2}O{sub 3} vitreous system

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, Noelio O.; Silva, Valdeir A., E-mail: noelio@ufu.br [Universidade Federal de Uberlandia (LNMIS/UFU), MG (Brazil). Instituto de Fisica. Laboratorio de Novos Materials Isolantes a Semicondutores; Neto, O.O.D. [Universidade Federal de Uberlandia (GOIQ/UFU), MG (Brazil). Instituto de Fisica. Grupo de Optica e Informacao Quantica; Nascimento, Marcio L.F. [Vitreous Materials Laboratory, Institute of Humanities, Arts and Sciences, Federal University of Bahia, Salvador, BA (Brazil); PROTEC/PEI-Postgraduate Program in Industrial Engineering, Department of Chemical Engineering. Polytechnic School, Federal University of Bahia, Salvador (Brazil)

    2012-07-01

    A glass matrix with nominal composition 50Li{sub 2}O.45B{sub 2}O{sub 3}.5Al{sub 2}O{sub 3} (mol%) was synthesized, and its physical properties were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD), and atomic force microscopy (AFM). The glass transition temperature T{sub g}, the crystallization-onset temperature T{sub x}, the crystallization peak temperatures T{sub c1} and T{sub c2}. and the fusion peak temperatures T{sub m1} and T{sub m2} were determined from at least two glass matrix phases to be approximately 382, 457, 486, 574, 761, and 787 °C, respectively, at 5 °C/min heating rate. Heat treatments at 450 °C for an increasing sequence of time intervals allowed control over the amount of crystallization. Additional information on the crystallization kinetics for the LBA glass matrix was gathered from AFM images, DTA thermograms, and XRD diffractograms. The latter technique showed that LiBO{sub 2} (ICDD-16568) and Li{sub 3}AIB{sub 2}O{sub 6} (ICDD- 51754) phases are formed in the glass-ceramic system. Debye-Schemer analysis of the XRD peaks revealed a competition between the evolutions of crystal phases during heat treatment. Activation energies for crystallization, obtained from theoretical models applied to the DTA data showed that the crystallization is heterogeneous. The AFM images demonstrated that this heterogeneous crystallization starts at the surface of the LBA glass matrix and identified crystal sizes in agreement with the results of the Debye-Schemer analysis. Our study shows that thermal and structural characterization techniques can be combined with theoretical results drawn from well-tested models to offer a unified view of crystallization in a glass-ceramics system. (author)

  1. Ab initio study of the elastic properties of single and polycrystal TiO{sub 2}, ZrO{sub 2} and HfO{sub 2} in the cotunnite structure

    Energy Technology Data Exchange (ETDEWEB)

    Caravaca, M A; Mino, J C; Perez, V J [Departamento de Fisico-Quimica, Facultad de Ingenieria, UNNE, Avenida Las Heras 727, CP 3500, Resistencia (Argentina); Casali, R A; Ponce, C A [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales y Agrimensura UNNE, Avenida Libertad 5600, CP 3400, Corrientes (Argentina)

    2009-01-07

    In this work, we study theoretically the elastic properties of the orthorhombic (Pnma) high-pressure phase of IV-B group oxides: titania, zirconia and hafnia. By means of the self-consistent SIESTA code, pseudopotentials, density functional theory in the LDA and GGA approximations, the total energies, hydrostatic pressures and stress tensor components are calculated. From the stress-strain relationships, in the linear regime, the elastic constants C{sub ij} are determined. Derived elastic constants, such as bulk, Young's and shear modulus, Poisson coefficient and brittle/ductile behavior are estimated with the polycrystalline approach, using Voigt-Reuss-Hill theories. We have found that C{sub 11}, C{sub 22} and C{sub 33} elastic constants of hafnia and zirconia show increased strength with respect to the experimental values of the normal phase, P 2{sub 1}/c. A similar situation applies to titania if these constants are compared with its normal phase, rutile. However, shear elastic constants C{sub 44}, C{sub 55} and C{sub 66} are similar to the values found in the normal phase. This fact increases the compound anisotropy as well as its ductile behavior. The dependence of unit-cell volumes under hydrostatic pressures is also analyzed. P-V data, fitted to third-order Birch-Murnaghan equations of state, provide the bulk modulus B{sub 0} and its pressure derivatives B'{sub 0}. In this case, LDA estimations show good agreement with respect to recent measured bulk moduli of ZrO{sub 2} and HfO{sub 2}. Thermo-acoustic properties, e.g. the propagation speed of transverse, longitudinal elastic waves together with associated Debye temperatures, are also estimated.

  2. Structural and crystallisation study of a rare earth alumino borosilicate glass designed for nuclear waste confinement; Etude de la structure et du comportement en cristallisation d'un verre nucleaire d'aluminoborosilicate de terre rare

    Energy Technology Data Exchange (ETDEWEB)

    Quintas, A

    2007-09-15

    This work is devoted to the study of a rare earth alumino borosilicate glass, which molar composition is 61,81 SiO{sub 2} - 3,05 Al{sub 2}O{sub 3} - 8,94 B{sub 2}O{sub 3} - 14,41 Na{sub 2}O - 6,33 CaO - 1,90 ZrO{sub 2} - 3,56 Nd{sub 2}O{sub 3}, and envisaged for the immobilization of nuclear wastes originating from the reprocessing of high discharge burn up spent fuel. From a structural viewpoint, we investigated the role of the modifier cations on the arrangement of the glass network through different modifications of the glass composition: variation of the Na/Ca ratio and modification of the nature of the alkali and alkaline earth cations. The NMR and Raman spectroscopic techniques were useful to determine the distribution of modifier cations among the glass network and also to cast light on the competition phenomena occurring between alkali and alkaline earth cations for charge compensation of [AlO{sub 4}]{sup -} and [BO{sub 4}]{sup -} species. The neodymium local environment could be probed by optical absorption and EXAFS spectroscopies which enabled to better understand the insertion mode of Nd{sup 3+} ions among the silicate domains of the glass network. Concerning the crystallization behavior we were interested in how the glass composition may influence the crystallization processes and especially the formation of the apatite phase of composition Ca{sub 2}Nd{sub 8}(SiO{sub 4}){sub 6}O{sub 2}. In particular, this work underlined the important role of both alkaline earth and rare earth cations on the crystallization of the apatite phase. (author)

  3. Paramagnetic limiting of the upper critical field of KFe{sub 2}As{sub 2} studied by low temperature thermal expansion and magnetostriction

    Energy Technology Data Exchange (ETDEWEB)

    Zocco, Diego A.; Grube, Kai; Zaum, Sebastian; Eilers, Felix; Schaefer, Roland; Wolf, Thomas; Burger, Philipp; Hardy, Frederic; Boehmer, Anna; Meingast, Christoph [Institut fuer Festkoerperphysik, Karlsruhe Institute of Technology, Karlsruhe (Germany); Loehneysen, Hilbert von [Institut fuer Festkoerperphysik, Karlsruhe Institute of Technology, Karlsruhe (Germany); Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe (Germany)

    2013-07-01

    We present low-temperature thermal expansion and magnetostriction measurements of single crystals of KFe{sub 2}As{sub 2} (T{sub c} ∝ 3.4 K) in magnetic fields up to 14 T applied parallel and perpendicular to the c-axis of the samples (B{sub c2}{sup c} ∝ 1.5 T and B{sub c2}{sup ab} ∝ 4.8 T). In the normal state, quantum oscillations of the sample length were observed for B parallel c and B perpendicular to c, giving estimated mean-free-path values of 177 and 52 nm, respectively, indicating that the superconducting state can be described as being in the clean limit (ξ{sub 0}{sup ab} ∝ 10 nm). While the superconducting state is limited by orbital pair-breaking effects when magnetic fields are applied parallel to the c-axis, our measurements confirm strong paramagnetic effects on B{sub c2}(T) along the ab direction, as it was similarly found in other Fe-based materials such as LiFeAs and FeSe{sub 1-x}Te{sub x}.

  4. Study of the growth of CuAlS{sub 2} thin films on oriented silicon (111)

    Energy Technology Data Exchange (ETDEWEB)

    Brini, R. [Laboratoire de Photovoltaique et Materiaux Semiconducteurs.(LPMS), Ecole Nationale d' ingenieurs de Tunis (ENIT), BP 37 le Belvedere 1002 Tunis (Tunisia)], E-mail: Brini_rawdha@yahoo.fr; Schmerber, G. [Institut de Physique et Chimie des Materiaux de Strasbourg (IPCMS) UMR7504 CNRS-ULP, 23 rue du Loess, BP 43, 67034 Strasbourg Cedex 2 (France); Kanzari, M. [Laboratoire de Photovoltaique et Materiaux Semiconducteurs.(LPMS), Ecole Nationale d' ingenieurs de Tunis (ENIT), BP 37 le Belvedere 1002 Tunis (Tunisia); Werckmann, J. [Institut de Physique et Chimie des Materiaux de Strasbourg (IPCMS) UMR7504 CNRS-ULP, 23 rue du Loess, BP 43, 67034 Strasbourg Cedex 2 (France); Rezig, B. [Laboratoire de Photovoltaique et Materiaux Semiconducteurs.(LPMS), Ecole Nationale d' ingenieurs de Tunis (ENIT), BP 37 le Belvedere 1002 Tunis (Tunisia)

    2009-02-02

    Within the chalcopyrite family the sulphur based compounds CuMS{sub 2} (M = In, Ga, Al) have attracted much interest in recent years because they show a direct wide band-gap covering from E{sub gap} = 1.53 eV (CuInS{sub 2}) over E{sub gap} = 2.43 eV (CuGaS{sub 2}) to E{sub gap} = 3.49 eV (CuAlS{sub 2}). Therefore they are particularly suitable for optoelectronic as well as photovoltaic applications. The CuAlS{sub 2} semiconductor is one of these compounds and has good luminescent properties and a wide direct gap of 3.5 eV making it suitable for the use as material for light-emitting devices in the blue region of the spectrum. To dig up fully its potential a better understanding of the fundamental properties of the CuAlS{sub 2} film itself is essential, which could be achieved from high-quality single-crystalline materials. So, the aim of this work has been to study the growth of multilayer CuAlS{sub 2} thin films on Si(111) substrates at a substrate temperature of 723 K. One, two and three layers with 60, 120 and 180 nm thicknesses, respectively, were deposited on Si(111) substrate. The effect of the CuAlS{sub 2} layer numbers on the structure, morphology and optical properties of the samples was investigated. The X-ray diffraction studies revealed that all the samples are polycrystalline in nature, single CuAlS{sub 2} phase and exhibiting chalcopyrite structure with a preferred orientation along the (112) direction. However, the sample with three CuAlS{sub 2} layers exhibit the highly oriented (112) plane with grain sizes of 80 nm. So we show that this experimental process affects significantly the structural properties of the CuAlS{sub 2} films. Raman spectroscopic measurements indicated five prominent peaks at 193, 205, 325, 335 and 370 cm{sup -1}. The possible origin of the 370 cm{sup -1} peak was investigated and was found to be some local vibration in the structure. The peaks at 193-205 and 335 cm{sup -1} were ascribed to A{sub 1} and B{sub 2} modes

  5. Comparative study of frying to other cooking techniques influence on the nutritive value

    Directory of Open Access Journals (Sweden)

    Bognár, A.

    1998-08-01

    Full Text Available Frying is one of the oldest methods of food preparation. It improves the sensory quality of food by formation of aroma compounds, attractive colour, crust and texture. Undesirable changes involved are loss of nutritive quality e.g. due to degradation of heat - susceptible vitamins. The influence of common frying methods (frying in an oven, in a pan deep frying on cooking time and nutritive value of vegetables, potatoes, meat, poultry and fish is described and compared to other cooking methods (boiling, steaming, stewing. Frying of vegetables, potatoes and breaded meat, poultry and fish, no matter whether in a pan or by deep - frying, is associated with fat uptake (2 - 14 g per 100 g of raw food while non - breaded high fat food of animal origin loses fat during frying (2 - 30%. Data suggest that the fat quantity absorbed during frying increases up to a saturation limit which depends on the kind of food and on the amount of panade. Deep - fried meat, poultry and fish usually absorb less fat than meat, poultry and fish fried in a pan. The kind of fat had no essential influence on fat uptake. After frying of vegetable food and of breaded meat, poultry and fish, the content of protein, carbohydrates and minerals was nearly fully retained while boiling and steaming reduced the mineral content by 25-50%. In the majority of cases frying including deep frying also retained the vitamins B>1, B>2, B>6 and C better than boiling, steaming and stewing.

  6. Numerical study of electron-leakage power loss in a tri-plate transmission line

    International Nuclear Information System (INIS)

    Numerical simulations have been conducted using NRL's DIODE2D computer code to model the steady-state behavior of electron flow in a radial diode and in its adjacent tri-plate transmission line (TTL). Particular attention was paid to the magnitude of the electron current flowing from the cathode to the anode surface in the TTL. A quantitative value for this effective power loss is given. The electron current is restricted mainly to the transition region in the TTL into which there is seepage of the B/sub z/ that is imposed in the diode gap. This finding highlights the importance of that region to diode designers

  7. Stability of superheavy elements around Z=120 probed by the study of their fission time obtained by the crystal blocking method; Stabilite d'elements superlourds au voisinage de Z=120 testee par l'etude de leurs temps de fission deduits par la methode du blocage cristallin

    Energy Technology Data Exchange (ETDEWEB)

    Laget, M

    2007-10-15

    While the existence of an island of stability beyond Z=110 is theoretically acquired, the location of this island ranges from Z=114 to Z=126 depending on models. In this work, the stability of super-heavy nuclei is probed through the study of their fission time. The chosen experimental method, the crystal blocking method, is sensitive to the presence of possible long time components in the fission time distribution which indicates a fission mechanism occurring after the formation of a compound nucleus. The blocking dips were therefore constituted for the various products of the reaction U{sup 238} + Ni (6.6 MeV/A) {yields} 120, the experimental set-up allowing us to clearly identify and select the reaction mechanisms. The comparison of the blocking dip constituted for quasi-elastic scattering events with the one obtained for the fission fragments of a Z=120, combined with the study of kinematical properties of these fission fragments, give evidences of the existence of very long fission times (> 10{sup -18} s) only compatible with a fusion-fission mechanism implying a non vanishing fission barrier height for Z=120. The second part outlines microscopic calculations of fission barrier heights, carried out in the framework of the finite temperature of the Hartree-Fock-Bogoliubov (HFB) theory. Because of the progressive vanishing of the pairing correlation with T, which happens differently at the ground state and at the top of the barrier, B{sub f} first grows until T {approx_equal} 0.8 MeV before dropping with T owing to shell-effects damping with temperature. (author)

  8. First-principles study of structural stabilities, elastic and electronic properties of transition metal monocarbides (TMCs) and mononitrides (TMNs)

    Energy Technology Data Exchange (ETDEWEB)

    Rached, H.; Rached, D.; Benalia, S. [Laboratoire des Matériaux Magnétiques, Faculté des Sciences, Université Djillali Liabès de Sidi Bel-Abbès, Sidi Bel-Abbès 22000 (Algeria); Reshak, A.H., E-mail: maalidph@yahoo.co.uk [Institute of Complex Systems, FFPW, CENAKVA, University of South Bohemia in CB, Nove Hrady 37333 (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia); Rabah, M. [Laboratoire des Matériaux Magnétiques, Faculté des Sciences, Université Djillali Liabès de Sidi Bel-Abbès, Sidi Bel-Abbès 22000 (Algeria); Khenata, R. [Laboratoire de Physique Quantique et de Modélisation Mathématique de la Matière (LPQ3M), université de Mascara, Mascara 29000 (Algeria); Bin Omran, S. [Department of Physics and Astronomy, Faculty of Science, King Saud University, Riyadh 11451 (Saudi Arabia)

    2013-12-16

    The structural stabilities, elastic and electronic properties of 5d transition metal mononitrides (TMNs) XN with (X = Ir, Os, Re, W and Ta) and 5d transition metal monocarbides (TMCs) XC with (X = Ir, Os, Re and Ta) were investigated using the full-potential linear muffin-tin orbital (FP-LMTO) method, in the framework of the density functional theory (DFT) within the local density approximation (LDA) for the exchange correlation functional. The ground state quantities such as the lattice parameter, bulks modulus and its pressure derivatives for the six considered crystal structures, Rock-salt (B1), CsCl (B2), zinc-blend (B3), Wurtzite (B4), NiAs (B8{sub 1}) and the tungsten carbides (B{sub h}) are calculated. The elastic constants of TMNs and TMCs compounds in its different stable phases are determined by using the total energy variation with strain technique. The elastic modulus for polycrystalline materials, shear modulus (G), Young's modulus (E), and Poisson's ratio (ν) are calculated. The Debye temperature (θ{sub D}) and sound velocities (v{sub m}) were also derived from the obtained elastic modulus. The analysis of the hardness of the herein studied compounds classifies OsN – (B4 et B8{sub 1}), ReN – (B8{sub 1}), WN – (B8{sub 1}) and OsC – (B8{sub 1}) as superhard materials. Our results for the band structure and densities of states (DOS), show that TMNs and TMCs compounds in theirs energetically and mechanically stable phase has metallic characteristic with strong covalent nature Metal–Nonmetal elements. - Highlights: • Structural stabilities, elastic, electronic properties of 5d TMNs XN are investigated. • 5d TMCs XC with (X = Ir, Os, Re and Ta) were investigated. • The ground state properties for the six considered crystal structure are calculated. • The elastic constants of TMNs and TMCs in its different stable phases are determined. • The elastic modulus for polycrystalline materials, G, E, and ν are calculated.

  9. Theoretical spectroscopy study of the low-lying electronic states of UX and UX{sup +}, X = F and Cl

    Energy Technology Data Exchange (ETDEWEB)

    Bross, David H.; Peterson, Kirk A., E-mail: kipeters@wsu.edu [Department of Chemistry, Washington State University, Pullman, Washington 99164-4630 (United States)

    2015-11-14

    Spectroscopic constants (T{sub e}, r{sub e}, B{sub 0}, ω{sub e}, and ω{sub e}x{sub e}) have been calculated for the low-lying electronic states of UF, UF{sup +}, UCl, and UCl{sup +} using complete active space 2nd-order perturbation theory (CASPT2), with a series of correlation consistent basis sets. The latter included those based on both pseudopotential (PP) and all-electron Douglas-Kroll-Hess Hamiltonians for the U atom. Spin orbit (SO) effects were included a posteriori using the state interacting method using both PP and Breit Pauli (BP) operators, as well as from exact two-component methods for U{sup +} and UF{sup +}. Complete basis set (CBS) limits were obtained by extrapolation where possible and the PP and BP calculations were compared at their respective CBS limits. The PP-based method was shown to be reliable in calculating spectroscopic constants, in particular when using the state interacting method with CASPT2 energies (SO-CASPT2). The two component calculations were limited by computational resources and could not include electron correlation from the nominally closed shell 6s and 6p orbitals of U. UF and UCl were both calculated to have Ω = 9/2 ground states. The first excited state of UCl was calculated to be an Ω = 7/2 state at 78 cm{sup −1} as opposed to the same state at 435 cm{sup −1} in UF, and the other low-lying states of UCl showed a similar compression relative to UF. Likewise, UF{sup +} and UCl{sup +} both have Ω = 4 ground states and the manifold of low-lying excited Ω = 3, 2, 1, 0 states was energetically closer together in UCl{sup +} than in UF{sup +}, ranging up to 776 cm{sup −1} in UF{sup +} and only 438 cm{sup −1} in UCl{sup +}. As in previous studies, the final PP-based SO-CASPT2 results for UF{sup +} and UF agree well with experiment and are expected to be predictive for UCl and UCl{sup +}, which are reported here for the first time.

  10. Pulmonary studies

    International Nuclear Information System (INIS)

    Radionuclide studies of the lung are described, as regards perfusion studies, ventilation studies and physiological considerations. The four principal applications for radionuclide studies of the lungs are outlined and the uses of these discussed in relation to particular entities including pulmonary embolic disease, congestive heart failure, asthma, acute, nonasthmatic, bronchial obstruction, chronic pulmonary disease and cancer. (Auth./C.F.)

  11. Beautiful CP violation

    Energy Technology Data Exchange (ETDEWEB)

    Dunietz, I.

    1997-09-24

    CP violation is observed to date only in K{sup 0} decays and is parameterizable by a single quantity {epsilon}. Because it is one of the least understood phenomena in the Standard Model and holds a clue to baryogenesis, it must be investigated further. Highly specialized searches in K{sup 0} decays are possible. Effects in B decays are much larger. In addition to the traditional B{sub d} {yields} J/{psi}K{sub S}, {pi}{sup +}{pi}{sup {minus}} asymmetries, CP violation could be searched for in already existing inclusive B data samples. The rapid B{sub s}--{anti B}{sub s} oscillations cancel in untagged B{sub s} data samples, which therefore allow feasibility studies for the observation of CP violation and the extraction of CKM elements with present vertex detectors. The favored method for the extraction of the CKM angle {gamma} is shown to be unfeasible and a solution is presented involving striking direct CP violation in charged B decays. Novel methods for determining the B{sub s} mixing parameter {Delta}m are described without the traditional requirement of flavor-specific final states.

  12. Beautiful CP violation

    Energy Technology Data Exchange (ETDEWEB)

    Dunietz, I. [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, Illinois 60510 (United States)

    1998-02-01

    CP violation is observed to date only in K{sup 0} decays and is parameterizable by a single quantity {epsilon}. Because it is one of the least understood phenomena in the Standard Model and holds a clue to baryogenesis, it must be investigated further. Highly specialized searches in K{sup 0} decays are possible. Effects in {ital B} decays are much larger. In addition to the traditional B{sub d}{r_arrow}J/{psi}K{sub S}, {pi}{sup +}{pi}{sup {minus}} asymmetries, CP violation could be searched for in already existing inclusive {ital B} data samples. The rapid B{sub s}{minus}{bar B}{sub s} oscillations cancel in untagged B{sub s} data samples, which therefore allow feasibility studies for the observation of CP violation and the extraction of CKM elements with present vertex detectors. The favored method for the extraction of the CKM angle {gamma} is shown to be unfeasible and a solution is presented involving striking direct CP violation in charged {ital B} decays. Novel methods for determining the B{sub s} mixing parameter {Delta}m are described without the traditional requirement of flavor-specific final states. {copyright} {ital 1998 American Institute of Physics.}

  13. Radiation-protective polymer-matrix nanostructured composites

    Energy Technology Data Exchange (ETDEWEB)

    Kaloshkin, S.D.; Tcherdyntsev, V.V. [College of Advanced Materials and Nanotechnologies, National University of Science and Technology ' MISiS' , Leninsky Prospect, 4 Moscow (Russian Federation); Gorshenkov, M.V., E-mail: mvg@misis.ru [College of Advanced Materials and Nanotechnologies, National University of Science and Technology ' MISiS' , Leninsky Prospect, 4 Moscow (Russian Federation); Gulbin, V.N. [College of Advanced Materials and Nanotechnologies, National University of Science and Technology ' MISiS' , Leninsky Prospect, 4 Moscow (Russian Federation); Kuznetsov, S.A. [Russian State Technological University ' MATI' , Orshanskaya 3, Moscow (Russian Federation)

    2012-09-25

    Highlights: Black-Right-Pointing-Pointer Radiation-protective composites were fabricated by solid state intermixing and thermal pressing. Black-Right-Pointing-Pointer The composites based on UHMWPE contain B{sub 4}S and W nanopowders as fillers. Black-Right-Pointing-Pointer The mechanical and {gamma}-radiation protective properties of the polymer-matrix nanocomposites were determined experimentally. Black-Right-Pointing-Pointer For composites containing 12% B{sub 4}C and 12% W the mechanical properties were studied prior to and after the irradiation with fast neutrons. - Abstract: UHMWPE-based nanostructured composites containing B{sub 4}C and W nanopowders were fabricated and studied. The mechanical and {gamma}-radiation protective properties of the polymer-matrix nanocomposites were determined experimentally. For selected composites the mechanical properties were studied prior to and after the irradiation.

  14. MATRIX 2 RESULTS OF THE FY07 ENHANCED DOE HIGH-LEVEL WASTE MELTER THROUGHPUT STUDIES AT SRNL

    Energy Technology Data Exchange (ETDEWEB)

    Raszewski, F; Tommy Edwards, T; David Peeler, D

    2008-10-23

    % (based strictly on retention or solubility). (2) For those study glasses that had very close compositional overlap with the model development and/or model validation ranges of the current DWPF TL model (except TiO{sub 2} and MgO concentrations), there was very little difference in the predicted and measured TL values. Even though the TiO{sub 2} concentrations were above the 2 wt% upper limit, the results indicate that the current T{sub L} model is applicable in this compositional region with TiO{sub 2} contents up to approximately 3.5 wt%. (3) As the target glass compositions diverge from the model development and validation ranges, the T{sub L} data suggest that the model under-predicted the measured values. These discrepancies imply that there are individual oxides or oxide combinations that need to be accounted for in the model. These oxides include B{sub 2}O{sub 3}, SiO{sub 2}, MnO, TiO{sub 2} and/or their combinations. More data would be required to fill in these anticipated DWPF compositional regions for higher WL glasses so that the model coefficients could be refit to account for these differences. (4) Based on PCT response of HWL-21 and HWL-22 (two glasses that were prone to nepheline formation) it appears that increasing the B{sub 2}O{sub 3} concentration in glass does not consistently suppress the formation of nepheline in glasses with higher Al{sub 2}O{sub 3} and/or Na{sub 2}O content. Although the chemical durabilities of the quenched versions of these glasses were very acceptable, the canister centerline cooled (ccc) glasses exhibited a considerable decrease in durability and were found to contain nepheline via XRD. In fact, one of the glasses had a release that was 5 times greater than that of the Environmental Assessment (EA) benchmark glass. These results suggest a need for a more fundamental understanding of the compositional and kinetic effects of nepheline formation in high WL glasses. (5) Data have been generated in support of the replacement of the

  15. Cystometric study

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003904.htm Cystometric study To use the sharing features on this page, please enable JavaScript. Cystometric study measures the amount of fluid in the bladder ...

  16. MATRIX 2 RESULTS OF THE FY07 ENHANCED DOE HIGH-LEVEL WASTE MELTER THROUGHPUT STUDIES AT SRNL

    Energy Technology Data Exchange (ETDEWEB)

    Raszewski, F; Tommy Edwards, T; David Peeler, D

    2008-10-23

    % (based strictly on retention or solubility). (2) For those study glasses that had very close compositional overlap with the model development and/or model validation ranges of the current DWPF TL model (except TiO{sub 2} and MgO concentrations), there was very little difference in the predicted and measured TL values. Even though the TiO{sub 2} concentrations were above the 2 wt% upper limit, the results indicate that the current T{sub L} model is applicable in this compositional region with TiO{sub 2} contents up to approximately 3.5 wt%. (3) As the target glass compositions diverge from the model development and validation ranges, the T{sub L} data suggest that the model under-predicted the measured values. These discrepancies imply that there are individual oxides or oxide combinations that need to be accounted for in the model. These oxides include B{sub 2}O{sub 3}, SiO{sub 2}, MnO, TiO{sub 2} and/or their combinations. More data would be required to fill in these anticipated DWPF compositional regions for higher WL glasses so that the model coefficients could be refit to account for these differences. (4) Based on PCT response of HWL-21 and HWL-22 (two glasses that were prone to nepheline formation) it appears that increasing the B{sub 2}O{sub 3} concentration in glass does not consistently suppress the formation of nepheline in glasses with higher Al{sub 2}O{sub 3} and/or Na{sub 2}O content. Although the chemical durabilities of the quenched versions of these glasses were very acceptable, the canister centerline cooled (ccc) glasses exhibited a considerable decrease in durability and were found to contain nepheline via XRD. In fact, one of the glasses had a release that was 5 times greater than that of the Environmental Assessment (EA) benchmark glass. These results suggest a need for a more fundamental understanding of the compositional and kinetic effects of nepheline formation in high WL glasses. (5) Data have been generated in support of the replacement of the

  17. Thin film and multilayer coating development for the extreme ultraviolet spectral region

    Energy Technology Data Exchange (ETDEWEB)

    Garoli, D. [INFM-LUXOR DEI University of Padova, via Gradenigo 6/B, 35131 Padova (Italy)]. E-mail: garoli@dei.unipd.it; Monaco, G. [INFM-LUXOR DEI University of Padova, via Gradenigo 6/B, 35131 Padova (Italy); Frassetto, F. [INFM-LUXOR DEI University of Padova, via Gradenigo 6/B, 35131 Padova (Italy); Pelizzo, M.G. [INFM-LUXOR DEI University of Padova, via Gradenigo 6/B, 35131 Padova (Italy); Nicolosi, P. [INFM-LUXOR DEI University of Padova, via Gradenigo 6/B, 35131 Padova (Italy); Armelao, L. [Dipartimento di Scienze Chimiche, University of Padova, Via Marzolo 1, 35131 Padova (Italy); Mattarello, V. [INFN-LNL, strada Romea 35020 Legnaro PD (Italy); Rigato, V. [INFN-LNL, strada Romea 35020 Legnaro PD (Italy)

    2006-11-15

    B{sub 4}C optical coating represents, together with Ir, Pt, SiC, one of best choice for high reflectance in the extreme ultraviolet region. This material is also used combined with others materials in multilayer such as Si/B{sub 4}C or as interlayer in Mo/Si multilayer to avoid interdiffusion. In this study we have performed optical, compositional and structural analyses for thin film of B{sub 4}C deposited by means of magnetron sputtering and on preliminary samples deposited by e-beam evaporation. Here we report reflectivity measurements and the derived optical constants of B{sub 4}C in the 400-1500 A region.

  18. Measurement of the relative branching ratio of B-s(0) -> J/psi f(0)(980) to B-s(0) -> J/psi phi

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Aoki, M.; Askew, A.; Asman, B.; Atkins, S.; Atramentov, O.; Augsten, K.; Avila, C.; BackusMayes, J.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Belanger-Champagne, C.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besancon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Bose, T.; Brandt, A.; Brandt, O.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Brown, J.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burnett, T. H.; Buszello, C. P.; Calpas, B.; Camacho-Perez, E.; Carrasco-Lizarraga, M. A.; Casey, B. C. K.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Chevalier-Thery, S.; Cho, D. K.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M. -C.; Croc, A.; Cutts, D.; Das, A.; Davies, G.; De, K.; de Jong, S. J.; De La Cruz-Burelo, E.; Deliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dorland, T.; Dubey, A.; Dudko, L. V.; Duggan, D.; Duperrin, A.; Dutt, S.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Facini, G.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garcia-Bellido, A.; Garcia-Guerra, G. A.; Gavrilov, V.; Gay, P.; Geng, W.; Gerbaudo, D.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Golovanov, G.; Goussiou, A.; Grannis, P. D.; Greder, S.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J. -F.; Grohsjean, A.; Gruenendahl, S.; Gruenewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hagopian, S.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffre, M.; Jamin, D.; Jayasinghe, A.; Jesik, R.; Johns, K.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kaadze, K.; Kajfasz, E.; Karmanov, D.; Kasper, P. A.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kulikov, S.; Kumar, A.; Kupco, A.; Kurca, T.; Kuzmin, V. A.; Kvita, J.; Lammers, S.; Landsberg, G.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lellouch, J.; Li, L.; Li, Q. Z.; Lietti, S. M.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; de Sa, R. Lopes; Lubatti, H. J.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Madar, R.; Magana-Villalba, R.; Malik, S.; Malyshev, V. L.; Maravin, Y.; Martinez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; et al.

    2012-01-20

    We present a measurement of the relative branching fraction, R{sub f{sub 0}/{phi}}, of B{sub s}{sup 0} {yields} J/{psi}f{sub 0}(980), with f{sub 0}(980) {yields} {pi}{sup +}{pi}{sup -}, to the process B{sub s}{sup 0} {yields} J/{psi}{phi}, with {phi} {yields} K{sup +}K{sup -}. The J/{psi}f{sub 0}(980) final state corresponds to a CP-odd eigenstate of B{sub s}{sup 0} that could be of interest in future studies of CP violation. Using 8 fb{sup -1} of data recorded with the D0 detector at the Fermilab Tevatron Collider, we find R{sub f{sub 0}/{phi}} = 0.275 {+-} 0.041(stat) {+-} 0.061(syst).

  19. Case Studies

    International Nuclear Information System (INIS)

    Proven options available to Sri Lanka for large scale electricity generation in the future are coal-fired thermal, oil-fired thermal and Nuclear. Four case studies for groups participated are indicated. Case study for group 1 is comparison of the three options by taking into consideration the capital and recurrent expenditure involved. Environmental effects of the three options are also given. Case study for group 2 is economic comparison of three renewable energy based power generation system. Case study for group 3 is based on energy conservation, efficiency, improvement and demand management. Assuming that a continuous saving of 20 MW of demand from 1996 onwards is effective two projects are suggested to achieve this result. Case study for group 4 is a feasibility study for hydro power development of the Kukule Ganga (river) in Sri Lanka. Participants are required to evaluate one of the three optional development concepts which are technically feasible

  20. Structural study and DC conductivity of vanadyl doped zinc lithium borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Seema [Physics Department, Deenbandhu Chhotu Ram University of Science & Technology, Murthal-131039 (India); Physics Department, Baba Mast Nath University, Asthal Bohr, Rohtak-124001 (India); Khasa, S., E-mail: skhasa@rediff.com; Dahiya, M. S.; Yadav, Arti [Physics Department, Deenbandhu Chhotu Ram University of Science & Technology, Murthal-131039 (India); Agarwal, A. [Applied Physics Department, Guru Jambheshwar University of Science & Technology, Hisar-125001 (India); Dahiya, S. [Physics Department, Baba Mast Nath University, Asthal Bohr, Rohtak-124001 (India)

    2015-06-24

    Glasses with composition xZnO⋅(30 − x)⋅Li{sub 2}O⋅70B{sub 2}O{sub 3} containing 2 mol% of V{sub 2}O{sub 5} (x = 0, 2, 5, 7 and 10) were prepared by standard melt-quench technique. The amorphous nature of the glass samples was confirmed by using x-ray diffraction. The structural changes in these glasses have been investigated by employing IR spectroscopy in the mid-IR range. The infrared spectroscopic analysis confirms the presence of both triangular and tetraheldral coordinated boron units and absence of boroxol ring. It also shows that metal-oxide vibrations are present which are due to the bonding of lithium and zinc ions with oxygen. The dc conductivity was measured in the temperature range 353-523 K. The dc conductivity results show that conductivity decreases and activation energy increases when Li{sub 2}O is replaced by ZnO, keeping the concentration of B{sub 2}O{sub 3} constant. Decrease in conductivity and increase in activation energy shows that addition of ZnO to the glass matrix shows a “blocking effect” on the overall mobility of alkali ions, but at higher concentration the hopping effect was also observed.

  1. Studies of impurity behavior in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Hill, K.W.; Bitter, M.; Bretz, N.L.; Diesso, M.; Efthimion, P.C.; Von Goeler, S.; Kiraly, J.; Ramsey, A.T.; Sauthoff, N.R.; Schivell, J.

    1986-03-01

    Central medium- and low-Z impurity concentrations and Z/sub eff/ have been measured by x-ray spectrometry in Tokamak Fusion Test Reactor discharges during three periods of operation. These were the (1) start-up period, (2) ohmic heating, and (3) ohmic heating portion of the two neutral beam periods, distinguished mainly by different vacuum vessel internal hardware and increasing plasma current and toroidal field capability. Plasma parameters spanned minor radius a = 0.41 - 0.83 m, major radius R = 2.1 - 3.1 m, current I/sub p = 0.25 - 2.0 MA, line-averaged electron density n-bar/sub e/ = 0.9 - 4.0 x 10/sup 19/ m/sup -3/, and toroidal magnetic field B/sub T/ = 1.8 - 4.0 T. The metal impurities came mostly from the limiter. At low densities titanium or nickel approached 1% of n/sub e/ during operation on a TiC-coated graphite or Inconel limiter, respectively. Lower levels of Cr, Fe, and Ni (less than or equal to0.1%) were observed with a graphite limiter at similarly low densities; these elements were removed mainly from stainless steel or Inconel hardware within the vacuum vessel during pulse discharge cleaning or plasma operation on an Inconel limiter and then deposited on the graphite limiter. Hardware closest to the graphite limiter contributed most to the deposits.

  2. Studies of impurity behavior in TFTR

    International Nuclear Information System (INIS)

    Central medium- and low-Z impurity concentrations and Z/sub eff/ have been measured by x-ray spectrometry in Tokamak Fusion Test Reactor discharges during three periods of operation. These were the (1) start-up period, (2) ohmic heating, and (3) ohmic heating portion of the two neutral beam periods, distinguished mainly by different vacuum vessel internal hardware and increasing plasma current and toroidal field capability. Plasma parameters spanned minor radius a = 0.41 - 0.83 m, major radius R = 2.1 - 3.1 m, current I/sub p = 0.25 - 2.0 MA, line-averaged electron density n-bar/sub e/ = 0.9 - 4.0 x 1019 m-3, and toroidal magnetic field B/sub T/ = 1.8 - 4.0 T. The metal impurities came mostly from the limiter. At low densities titanium or nickel approached 1% of n/sub e/ during operation on a TiC-coated graphite or Inconel limiter, respectively. Lower levels of Cr, Fe, and Ni (less than or equal to0.1%) were observed with a graphite limiter at similarly low densities; these elements were removed mainly from stainless steel or Inconel hardware within the vacuum vessel during pulse discharge cleaning or plasma operation on an Inconel limiter and then deposited on the graphite limiter. Hardware closest to the graphite limiter contributed most to the deposits

  3. Studying Zooarchaeology

    Science.gov (United States)

    Moore, Molly; Wolf, Deborah; Butler, Virginia L.

    2012-01-01

    Children often associate the study of bones with dinosaurs or crime scenes. This unit introduces students to "zooarchaeology," the study of animal remains from archaeological sites. Students in grades 3-5 engage in hands-on activities examining bones, shells, and other "hard parts" of animals. They use their observations as a starting point for…

  4. Observation of Bs-Bsbar Oscillations Using Partially Reconstructed Hadronic Bs Decays

    Energy Technology Data Exchange (ETDEWEB)

    Miles, Jeffrey Robert; /MIT

    2007-09-01

    This thesis describes the contribution of partially reconstructed hadronic decays in the world's first observation of B{sub s}{sup 0}-{bar B}{sub s}{sup 0} oscillations. The analysis is a core member of a suite of closely related studies whose combined time-dependent measurement of the B{sub s}{sup 0}-{bar B}{sub s}{sup 0} oscillation frequency {Delta}m{sub s} is of historic significance. Using a data sample of 1 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected with the CDF-II detector at the Fermilab Tevatron, they find signals of 3150 partially reconstructed hadronic B{sub s} decays from the combined decay channels B{sub s}{sup 0} {yields} D*{sub s}{sup -} {pi}{sup +} and B{sub s}{sup 0} {yields} D{sub s}{sup -} {rho}{sup +} with D{sub s}{sup -} {yields} {phi}{pi}{sup -}. These events are analyzed in parallel with 2000 fully reconstructed B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +} (D{sub s}{sup -} {yields} {phi}{pi}{sup -}) decays. The treatment of the data is developed in stages of progressive complexity, using high-statistics samples of hadronic B{sup 0} and B{sup +} decays to study the attributes of partially reconstructed events. The analysis characterizes the data in mass and proper decay time, noting the potential of the partially reconstructed decays for precise measurement of B branching fractions and lifetimes, but consistently focusing on the effectiveness of the model for the oscillation measurement. They efficiently incorporate the measured quantities of each decay into a maximum likelihood fitting framework, from which they extract amplitude scans and a direct measurement of the oscillation frequency. The features of the amplitude scans are consistent with expected behavior, supporting the correctness of the calibrations for proper time uncertainty and flavor tagging dilution. The likelihood allows for the smooth combination of this analysis with results from other data samples, including 3500 fully reconstructed

  5. Human Vitamin B12 Absorption and Metabolism are Measured by Accelerator Mass Spectrometry Using Specifically Labeled 14C-Cobalamin

    Energy Technology Data Exchange (ETDEWEB)

    Carkeet, C; Dueker, S R; Lango, J; Buchholz, B A; Miller, J W; Green, R; Hammock, B D; Roth, J R; Anderson, P J

    2006-01-26

    There is need for an improved test of human ability to assimilate dietary vitamin B{sub 12}. Assaying and understanding absorption and uptake of B{sub 12} is important because defects can lead to hematological and neurological complications. Accelerator mass spectrometry (AMS) is uniquely suited for assessing absorption and kinetics of {sup 14}C-labeled substances after oral ingestion because it is more sensitive than decay counting and can measure levels of carbon-14 ({sup 14}C) in microliter volumes of biological samples, with negligible exposure of subjects to radioactivity. The test we describe employs amounts of B{sub 12} in the range of normal dietary intake. The B{sub 12} used was quantitatively labeled with {sup 14}C at one particular atom of the DMB moiety by exploiting idiosyncrasies of Salmonellametabolism. In order to grow aerobically on ethanolamine, S. entericamust be provided with either pre-formed B{sub 12} or two of its precursors: cobinamide and dimethylbenzimidazole (DMB). When provided with {sup 14}C-DMB specifically labeled in the C2 position, cells produced {sup 14}C-B{sub 12} of high specific activity (2.1 GBq/mmol, 58 mCi/mmol) and no detectable dilution of label from endogenous DMB synthesis. In a human kinetic study, a physiological dose (1.5 mg, 2.2 KBq/59 nCi) of purified {sup 14}C-B{sub 12} was administered and showed plasma appearance and clearance curves consistent with the predicted behavior of the pure vitamin. This method opens new avenues for study of B{sub 12} assimilation.

  6. {sup 10}Boron distribution measurement in laser ablated B{sub 4}C thin films using (n,alpha) reaction and LR-115 passive detector

    Energy Technology Data Exchange (ETDEWEB)

    Sajo-Bohus, L., E-mail: sajobohus@gmail.co [Universidad Simon Bolivar, Nuclear Physics Section, Valle de Sartenejas, Caracas 89000A (Venezuela, Bolivarian Republic of); Simon, A. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen 4026 (Hungary); Csako, T. [Dep. of Optics and Quantum Electronics, University of Szeged, P.O. Box 406, H-6701 Szeged (Hungary); Nemeth, P.; Palacios, D. [Universidad Simon Bolivar, Nuclear Physics Section, Valle de Sartenejas, Caracas 89000A (Venezuela, Bolivarian Republic of); Espinosa, G. [Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Greaves, E.D. [Universidad Simon Bolivar, Nuclear Physics Section, Valle de Sartenejas, Caracas 89000A (Venezuela, Bolivarian Republic of); Szoerenyi, T. [Dep. of Nat. Sci. and Environ. Prot., College of Dunaujvaros, P.O. Box 152, H-2401 Dunaujvaros (Hungary); Barros, H. [Universidad Simon Bolivar, Nuclear Physics Section, Valle de Sartenejas, Caracas 89000A (Venezuela, Bolivarian Republic of)

    2009-10-15

    Lateral distribution of the {sup 10}B isotope within a boron carbide film of 550 nm maximum thickness deposited on silicon wafer using pulsed laser deposition technique has been determined taking advantage of the high cross section for (n,alpha) reaction and nuclear tracks detectors (NTD - LR-115 Kodak Pathe). A radioisotope neutron source ({sup 252}Cf, 20 mug) and a 60 x 60 x 80 cm{sup 3} graphite cube as moderator produce a relatively uniform thermal neutron field. Details of the passive detector etching process and data processing are included. The track density reveals the boron density spatial distribution. A 3D picture is produced to visualize the boron-10 spatial distribution. The result suggests that a gradient in the boron distribution exists to almost a factor of three. The advantages of the technique are discussed.

  7. The adenosine A2B> receptor is involved in anion secretion in human pancreatic duct Capan-1 epithelial cells

    DEFF Research Database (Denmark)

    Hayashi, M.; Inagaki, A.; Novak, Ivana;

    2016-01-01

    Adenosine modulates a wide variety of biological processes via adenosine receptors. In the exocrine pancreas, adenosine regulates transepithelial anion secretion in duct cells and is considered to play a role in acini-to-duct signaling. To identify the functional adenosine receptors and Cl− chann...

  8. Afnor NF D 35-330. Gas-fired central heating boilers. Type B{sub 11} and B{sub 11BIS} boilers fitted with atmospheric burners of nominal heat input not exceeding 70 kW. (European standard EN 297); Afnor NF D 35-330. Chaudieres de chauffage central utilisant les combustibles gazeux. Chaudieres des types B{sub 11} et B{sub 11BIS} equipees de bruleurs atmospheriques dont le debit calorifique nominal est inferieur ou egal a 70 kW. (Norme europeenne EN 297)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-10-01

    This standard document defines the specifications and testing techniques relative to the manufacturing, safety, energy rational use, functioning capacity, classification and labeling of gas-fueled heating plants. It replaces the previous NF D 35-331 norm from November 1989 which comprised the NF D 35-331 norm from January 1980, its additives 1 (January 1980) and 2 (June 1984), its modifications 1 (July 1980), 2 (September 1986), 3 (December 1988) and 4 (November 1989) and the D 30-005 experimental norm of November 1991. (J.S.)

  9. Vitamin B>12 deficiency in the brain leads to DNA hypomethylation in the TCblR/CD320 knockout mouse

    OpenAIRE

    Fernàndez-Roig Sílvia; Lai Shao-Chiang; Murphy Michelle M; Fernandez-Ballart Joan; Quadros Edward V

    2012-01-01

    Abstract Background DNA methylation is an epigenetic phenomenon that can modulate gene function by up or downregulation of gene expression. Vitamin B12 and folate pathways are involved in the production of S-Adenosylmethionine, the universal methyl donor. Findings Brain vitamin B12 concentration and global DNA methylation was determined in transcobalamin receptor (TCblR/CD320) knock out (KO) (n = 4) and control mice (n = 4) at 20–24 weeks of age. Median [IQR] brain vitamin B12 concentrations ...

  10. Behavior of BWR-type fuel elements with B{sub 4}C/steel absorber tested under severe fuel damage conditions in the CORA facility

    Energy Technology Data Exchange (ETDEWEB)

    Sepold, L.; Hagen, S.; Hofmann, P.; Schanz, G.

    2009-01-15

    The CORA experiments carried out in an out-of-pile facility at the Kernforschungszentrum Karlsruhe (KfK), Federal Republic of Germany, are part of the ''Severe Fuel Damage'' (SFD) program. The experimental program was to provide information on the failure mechanisms of Light Water Reactor (LWR) fuel elements in a temperature range from 1200 C to 2000 C and in a few cases up to 2400 C. In the CORA experiments two different bundle configurations were tested: PWR (Pressurized Water Reactor) and BWR (Boiling Water Reactor) bundles. The BWR-type bundles consisted of 18 fuel rod simulators (heated and unheated rods), an absorber blade of steel containing eleven absorber rods filled with boron carbide powder. The larger bundle CORA-18 contained the same number of absorber rods but was made up of 48 fuel rod simulators. All BWR bundles were surrounded by a zircaloy shroud and the absorber blades by a channel box wall on each side, also made of zircaloy. The test bundles were subjected to temperature transients of a slow heatup rate in a steam environment. Thus, an accident sequence was simulated, which may develop from a small-break loss-of-coolant accident of a LWR. The transient phases of the tests were initiated with a temperature ramp rate of 1 K/s. The temperature escalation due to the exothermal zircaloy(Zry)-steam reaction started at about 1100 C, leading the bundles to maximum temperatures of approximately 2000 C. In all experiments bundle destruction started in the upper region (axially) with melting of the absorber blade and the absorber rod cladding at about 1250 C by interaction of boron carbide and steel. After destruction of the channel box walls this melt attacked the zircaloy fuel rod cladding and started to interact with the UO{sub 2} pellets. The test bundles also resulted in severe oxidation of the following components made of zircaloy: shroud, cladding, and grid spacers at the central and upper positions. Relocated absorber melt formed extended blockages at lower elevations of the bundles. This distribution of absorber material could in the type of reactor accident described with subsequent flooding of the partially destroyed reactor core with unborated water lead to local recriticalities. There was no difference in the behavior of the large bundle CORA-18 compared to the BWR test bundles of regular size, i.e. CORA-16 and CORA-17. Quenching (flooding) of a degraded BWR-type bundle (CORA-17) exhibits identical behavior as observed in the PWR-type quenching experiments: The bundle results in locally enhanced zircaloy/steam reaction causing a renewed temperature rise, an additional meltdown of materials, and an additional strong hydrogen generation. (orig.)

  11. Anisotropic Multiband Many-Body Interactions in LuNi2B2C

    Energy Technology Data Exchange (ETDEWEB)

    Bergk, B.; Petzold, V.; Rosner, H.; Drechsler, S.-L.; Bartkowiak, M.; Ignatchik, O.; Bianchi, A. D.; Sheikin, I.; Canfield, P. C.; Wosnitza, J.

    2008-06-27

    We present a comprehensive de Haas-van Alphen study on the nonmagnetic borocarbide superconductor LuNi{sub 2}B{sub 2}C. The analysis of the angular-dependent effective masses for different bands in combination with full-potential density functional calculations allowed us to determine the mass-enhancement factors, {lambda}, for the different electronic bands and their wave-vector dependences. Our data clearly show the anisotropic multiband character of the superconductivity in LuNi{sub 2}B{sub 2}C.

  12. Effects of impeller shape of submersible nonclogging pump on its performance

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Jeong Eui [Kangwon Nat' l Univ., Chuncheon (Korea, Republic of)

    2012-12-15

    This study was performed to develop a high efficiency submersible nonclogging pump impeller. Toward this end, we simulated the effect of some parameters such as the outlet position of a blade ({Dirac_h}{sub {Oota}}), outlet width of a blade (b{sub 2}), and hub profile on the pump efficiency by using the commercial codes ANSYS CFX and BladeGen. The results showed that the pump efficiency was proportional up to {Dirac_h}{sub {Oota}} and b{sub 2} in the simulated ranges. The effects of hub profile changes on the pump efficiency were relatively small compared to those of the other parameters.

  13. Initial Study

    DEFF Research Database (Denmark)

    Torp, Kristian

    2009-01-01

    Congestion is a major problem in most cities and the problem is growing (Quiroga, 2000) (Faghri & Hamad, 2002). When the congestion level is increased the drivers notice this as delays in the traffic (Taylor, Woolley, & Zito, 2000), i.e., the travel time for the individual driver is simply...... increased. In the initial study presented here, the time it takes to pass an intersection is studied in details. Two major signal-controlled four-way intersections in the center of the city Aalborg are studied in details to estimate the congestion levels in these intersections, based on the time it takes...

  14. Measurement of charm and beauty-production in deep inelastic scattering at HERA and test beam studies of ATLAS pixel sensors

    Energy Technology Data Exchange (ETDEWEB)

    Libov, Vladyslav

    2013-08-15

    A measurement of charm and beauty production in Deep Inelastic Scattering at HERA is presented. The analysis is based on the data sample collected by the ZEUS detector in the period from 2003 to 2007 corresponding to an integrated luminosity of 354 pb{sup -1}. The kinematic region of the measurement is given by 54.2(5) GeV for charm (beauty) and -1.6<{eta}{sup jet}<2.2 for both charm and beauty, where E{sup jet}{sub T} and {eta}{sup jet} are the transverse energy and pseudorapidity of the jet, respectively. The significance of the decay length and the invariant mass of charged tracks associated with the secondary vertex are used as discriminating variables to distinguish between signal and background. Differential cross sections of jet production in charm and beauty events as a function of Q{sup 2}, y, E{sup jet}{sub T} and {eta}{sup jet} are measured. Results are compared to Next-to-Leading Order (NLO) predictions from Quantum Chromodynamics (QCD) in the fixed flavour number scheme. Good agreement between data and theory is observed. Contributions of the charm and beauty production to the inclusive proton structure function, F{sup cbar} {sup c}{sub 2} and F{sup b} {sup anti} {sup b}{sub 2}, are determined by extrapolating the double differential cross sections using NLO QCD predictions. Contributions to the test beam program for the Insertable B-Layer upgrade project of the ATLAS pixel detector are discussed. The test beam data analysis software package EUTelescope was extended, which allowed an efficient analysis of ATLAS pixel sensors. The USBPix DAQ system was integrated into the EUDET telescope allowing test beam

  15. Floodplain Study

    Data.gov (United States)

    Montgomery County of Maryland — The purpose of a floodplain study is to establish the 100-year floodplain limits within or near a development in order to preserve the natural resources within the...

  16. Actuarial Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Office of the Actuary in the Centers for Medicare and Medicaid Services (CMS) from time to time conducts studies on various aspects of the Medicare and Medicaid...

  17. Feasibility study

    International Nuclear Information System (INIS)

    The feasibility study itself examines the technical, economic and financial implications of a nuclear power station in depth so as to make sure that nuclear power is the right course to take. This means that it is quite an expensive operation and it is to avoid wasting this money that a pre-feasibility study is carried out. This preliminary study should eliminate cases where the electrical system cannot absorb the capacity of a nuclear station of commercial size, where other sources of power such as hydro-electricity, gas or cheap coal would make nuclear obviously uneconomic or where no suitable sites exist. If this first rather simple survey shows that nuclear power is a credible solution to a utilities need for electricity or heat production plant, then the next stage is a full feasibility study. (orig./TK)

  18. Studying Sideways

    DEFF Research Database (Denmark)

    Plesner, Ursula

    2011-01-01

    inequalities in relation to the people we study. This article argues that not all types of social scientific research interviews benefit from an à priori problematization of power and control, ethics and equality, or emancipation. From a constructivist perspective, the article seeks to displace...... the methodological concern with power related to the ideas of studying up or down and introduce another set of concerns in relation to producing good empirical material when we “study sideways.” The argument is based on analyses of interview situations from a concrete research project, where researcher...... and researched share professional background to some degree, where negotiations replace a researcher-imposed dialogue, and where the circulation of shared or common concepts messes up an orderly division between researchers’ vocabulary and interviewees’ vocabularies. It is proposed that when we study sideways...

  19. Writing Study and Grammar Study

    Institute of Scientific and Technical Information of China (English)

    马青

    2013-01-01

    This study is undertaken to describe,classify and analyze the problems in Chinese college students’ writing of CET-4 through contrastive analysis,statistical analysis and error analysis.The main problems appearing in CET-4 writing are the wrong usage of words,sentence structures and the lack of coherence.Meanwhile it proves grammar study plays an important and basic role in CET-4 writing.

  20. Security studies

    International Nuclear Information System (INIS)

    Full text: Security studies constitute one of the major tools for evaluating the provisions implemented at facilities to protect and control Nuclear Material against unauthorized removal. Operators use security studies to demonstrate that they are complying with objectives set by the Competent Authority to counter internal or external acts aimed at unauthorized removal of NM. The paper presents the context of security studies carried out in France. The philosophy of these studies is based on a postulated unauthorized removal of NM and the study of the behavior of the systems implemented to control and protect NM in a facility. The potential unauthorized removal of NM usually may take place in two stages. The first stage involves the sequence leading to handling of the NM. It occurs inside the physical barriers of a facility and may include action involving the documents corresponding to Material Control and Accounting systems. At this stage it is possible to limit the risk of unauthorized removal of NM by means of detection capabilities of the MC and A systems. The second stage is more specific to theft and involves removing the NM out of the physical barriers of a facility in which they are being held, notably by affecting the Physical Protection System. Operators have to study, from a quantity and time lapse point of view, the ability of the installed systems to detect unauthorized removal, as well as the possibility of tampering with the systems to mask unlawful operations. Operators have also to analyze the sequences during which NM are accessed, removed from their containment and further removed from the facility in which they are stored. At each stage in the process, the probability of detection and the time taken to carry out the above actions have to be estimated. Of course, these two types of studies complement each other. Security studies have begun, in France, for more than fifteen years. Up to now more than fifty security studies are available in the

  1. A comparative study of the Au + H{sub 2}, Au{sup +} + H{sub 2}, and Au{sup −} + H{sub 2} systems: Potential energy surfaces and dynamics of reactive collisions

    Energy Technology Data Exchange (ETDEWEB)

    Dorta-Urra, Anaís [Facultad de Ciencias Básicas y Aplicadas, Departamento de Física, Universidad Militar Nueva Granada, Bogotá DC (Colombia); Zanchet, Alexandre; Roncero, Octavio [Instituto de Física Fundamental, CSIC Serrano 123, 28006 Madrid (Spain); Aguado, Alfredo [Facultad de Ciencias, Departamento de Química-Física Aplicada, Unidad Asociada CSIC-UAM, Universidad Autónoma de Madrid, 28049 Madrid (Spain)

    2015-04-21

    In order to study the Au{sup −} + H{sub 2} collision, a new global potential energy surface (PES) describing the ground electronic state of AuH{sub 2}{sup −} system is developed and compared with the PESs of the neutral [Zanchet et al., J. Chem. Phys. 132, 034301 (2010)] and cationic systems [Anaís et al., J. Chem. Phys. 135, 091102 (2011)]. We found that Au{sup −} − H{sub 2} presents a H-Au-H insertion minimum attributed to the stabilization of the LUMO 3b{sub 2} orbital, which can be considered as the preamble of the chemisorption well appearing in larger gold clusters. While the LUMO orbital is stabilized, the HOMO 6a{sub 1} is destabilized, creating a barrier at the geometry where the energy orbitals’ curves are crossing. In the anion, this HOMO is doubly occupied, while in the neutral system is half-filled and completely empty in the cation, explaining the gradual disappearance of the well and the barrier as the number of electrons decreases. The cation presents a well in the entrance channel partially explained by electrostatic interactions. The three systems’ reactions are highly endothermic, by 1.66, 2.79, and 3.23 eV for AuH, AuH{sup +}, and AuH{sup −} products, respectively. The reaction dynamics is studied using quasi-classical trajectory method for the three systems. The one corresponding to the anionic system is new in this work. Collision energies between 1.00 and 8.00 eV, measured for the cation, are in good agreement with the simulated cross section for the AuH{sup +}. It was also found that the total fragmentation, in three atoms, competes becoming dominant at sufficiently high energy. Here, we study the competition between the two different reaction pathways for the anionic, cationic, and neutral species, explaining the differences using a simple model based on the topology of the potential energy surfaces.

  2. Weak matrix elements on the lattice - Circa 1995

    Energy Technology Data Exchange (ETDEWEB)

    Soni, A.

    1995-10-03

    Status of weak matrix elements is reviewed. In particular, e{prime}/e, B {yields} K*{gamma}, B{sub B} and B{sub B}, are discussed and the overall situation with respect to the lattice effort and some of its phenomenological implications are summarised. For e{prime}/e the need for the relevant matrix elements is stressed in view of the forthcoming improved experiments. For some of the operators, (e.g. O{sub 6}), even bound on their matrix elements would be very helpful. On B {yields} K{degrees}{gamma}, a constant behavior of T{sub 2} appears disfavored although dependence of T{sub 2} could, of course, be milder than a simple pole. Improved data is badly needed to settle this important issue firmly, especially in view of its ramification for extractions of V{sub td} from B {yields} {rho}{gamma}. On B{sub {kappa}}, the preliminary result from JLQCD appears to contradict Sharpe et al. JLQCD data seems to fit very well to linear {alpha} dependence and leads to an appreciably lower value of B{sub {kappa}}. Four studies of B{sub {kappa}} in the {open_quotes}full{close_quotes} (n{sub f} = 2) theory indicate very little quenching effects on B{sub {kappa}}; the full theory value seems to be just a little less than the quenched result. Based on expectations from HQET, analysis of B-parameter (B{sub h}{ell}) for the heavy-light mesons via B{sub h}{ell}) = constant + constants{prime}/m{sub h}{ell} is suggested. A summary of an illustrative sample of hadron matrix elements is given and constraints on CKM parameters (e.g. V{sub td}/V{sub ts}, on the unitarity triangle and on x{sub s}/x{sub d}, emerging from the lattice calculations along with experimental results are briefly discussed. In quite a few cases, for the first time, some indication of quenching errors on weak matrix elements are now becoming available.

  3. Study protocol

    DEFF Research Database (Denmark)

    Thorsteinsson, Troels; Helms, Anne Sofie; Adamsen, Lis;

    2013-01-01

    of first-line cancer therapy. Secondary endpoints are quality of life measured by validated questionnaires and interviews, and physical performance. RESPECT includes a multimodal intervention program, including ambassador-facilitated educational, physical, and social interventions. The educational......Background During cancer treatment children have reduced contact with their social network of friends, and have limited participation in education, sports, and leisure activities. During and following cancer treatment, children describe school related problems, reduced physical fitness......, and problems related to interaction with peers. Methods/design The RESPECT study is a nationwide population-based prospective, controlled, mixed-methods intervention study looking at children aged 6-18 years newly diagnosed with cancer in eastern Denmark (n = 120) and a matched control group in western Denmark...

  4. Treatability studies

    DEFF Research Database (Denmark)

    Bennedsen, Lars Rønn; Studds, Phil

    developed a mobile test unit including equipment for both standard and more advanced oxidation test directly on the site. The remediation techniques included are electrochemical oxidation, photochemical/photocatalytic oxidation, ozone, Fenton’s, permanganate, and persulfate among others. A versatile...... construction of the test unit makes it possible to combine different techniques in order to obtain more aggressive and effective remediation technologies, e.g. UV/ozone or electrochemical/H2O2. Actual case study data is presented to illustrate the benefits of in situ treatability tests prior to full scale......The fundamental information that a well-designed treatability study can provide is essential to the success of all remediation systems. Over the past years several new techniques for in situ and on site remediation of contaminated soil and groundwater have been used with varying degrees of success...

  5. Invisibility Studies

    DEFF Research Database (Denmark)

    Invisibility Studies explores current changes in the relationship between what we consider visible and what invisible in different areas of contemporary culture. Contributions trace how these changes make their marks on various cultural fields and investigate the cultural significance...... of these developments, such as transparency and privacy in urban architecture and the silent invasion of surveillance technologies into everyday life. The book contends that when it comes to the changing relationship of the visible and the invisible, the connection between seeing and not being seen is an exchange...... conditioned by physical and social settings that create certain possibilities for visibility and visuality, yet exclude others. The richness and complexity of this cultural framework means that no single discipline or interdisciplinary approach could capture it single-handedly. Invisibility Studies begins...

  6. Studying Adolescence

    OpenAIRE

    Richter, Linda M.

    2006-01-01

    Young people in their teens constitute the largest age group in the world, in a special stage recognized across the globe as the link in the life cycle between childhood and adulthood. Longitudinal studies in both developed and developing countries and better measurements of adolescent behavior are producing new insights. The physical and psychosocial changes that occur during puberty make manifest generational and early-childhood risks to development, in the form of individual differences in...

  7. Study protocol

    DEFF Research Database (Denmark)

    Madsen, Helle Østergaard; Dam, Ole Henrik; Hageman, Ida

    2012-01-01

    yields a Global Seasonal Score and a prevalence of SAD. Outcomes from the two groups will be compared. Moreover, outcomes from subgroups of the visually impaired population will be compared. ETHICS AND DISSEMINATION: The study is approved by the Danish Data Protection Agency. Results will be published...... in persons with severe visual impairments or blindness and to compare the results to a control group without visual impairments. Moreover, the authors wish to investigate whether SAD is correlated to the degree of impairment or to the diagnosis. METHODS AND ANALYSIS: 2781 persons with visual impairments...

  8. Se EXAFS study of the elevated wurtzite to rock salt structural phase transition in CdSe nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, S.H.; Alivisatos, A.P. [Lawrence Berkeley Lab., CA (United States)]|[California Univ., Berkeley, CA (United States). Dept. of Chemistry

    1993-09-01

    High pressure Se EXAFS data has been obtained on 2.7 nm radius CdSe semiconductor nanocrystals. This system is observed to undergo a solid-solid phase transition at 6.5 GPa which is approximately twice the reported value for bulk CdSe. In combination with high pressure optical absorption experiments, EXAFS data can be used to identify the high-pressure phase structure as rock salt. EXAFS data can be fit with equations of state to yield pressure volume curves. Resultant values of bulk modulus and its derivative with respect to pressure are B{sub o} = 37 {plus_minus} 5 GPa and B{sub o}{prime} = 11 {plus_minus} 3. A thermodynamic model for the data is presented in which the internal energy in each phase is modified by a surface energy term. Differences in surface energy are used to explain the elevation in phase transition pressure. The model can be used to estimate a value for the surface energy in the rock salt phase; 1.9 {plus_minus} 0.3 N/m is obtained in comparison to 0.9 {plus_minus} 0. 1 N/m for the wurtzite phase.

  9. The magnetic behavior of the intermetallic compound NdMn{sub 2}Ge{sub 2} studied by magnetization and hyperfine interactions measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bosch-Santos, B., E-mail: brianna@usp.br; Carbonari, A. W.; Cabrera-Pasca, G. A.; Saxena, R. N. [Instituto de Pesquisas Energéticas e Nucleares, Universidade de São Paulo, 05508-000 São Paulo (Brazil); Freitas, R. S. [Instituto de Física, Universidade de São Paulo, CP 66318, 05314-970 São Paulo (Brazil)

    2015-05-07

    The magnetic behavior of the intermetallic compound NdMn{sub 2}Ge{sub 2} was investigated by bulk magnetization measurements and measurements of hyperfine interactions using perturbed γ–γ angular correlation (PAC) spectroscopy. Magnetization measurements indicate the presence of four magnetic transitions associated with the Mn and Nd magnetic sublattices. At high temperatures, magnetic measurements show a change in the slope of the magnetization due to an antiferromagnetic transition around T{sub N} ∼ 425 K and a well defined ferromagnetic transition at T{sub C} ∼ 320 K. Moreover, at ∼210 K a peak is observed in the magnetization curve, which is assigned to the reorientation of the Mn spin, and at ∼25 K an increase in the magnetic moment is also observed, which is ascribed to the ordering of Nd ions. PAC measurements using {sup 140}La({sup 140}Ce) and {sup 111}In({sup 111}Cd) probe nuclei allowed the determination of the temperature dependence of the magnetic hyperfine field (B{sub hf}) at Nd and Mn sites, respectively. PAC results with {sup 111}Cd probe nuclei at Mn sites show that the dependence of B{sub hf} with temperature follows the expected behavior for the host magnetization associated with the magnetic ordering of Mn ions. From these results, the antiferromagnetic transition followed by a ferromagnetic ordering is clearly observed. PAC results with {sup 140}Ce probe nuclei at Nd sites, however, showed a strong deviation from the Brillouin function, which is attributed to the Ce 4f-electron contribution to B{sub hf}.

  10. SOCIOLOGICAL STUDIES

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    PAPER Post-Sociology: Exploration and Reflection Xie Lizhong Abstract: "Post-Sociology" refers to a new perspective which is different from tradi- tional perspectives of social studies. "Post-Social History" and "Pluralistic Discourse Analysis" could be seen as its two specific examples. "Discourse Constructivism" and "Pluralism" are the two core concepts of "Post-Sociology". That encouraging people to realize that all "social reality" including our experiences, thoughts and speech are just a "discoursive reality" constructed by social actors under the guidance and constraints of certain discourse system, is the major significance of "PostSociology". Some critics on "Post-Sociology" are misunderstandings, while others couldn't stand to strict analysis.

  11. Conceptual study

    International Nuclear Information System (INIS)

    This appendix is a compendium of topical reports prepared for the Hanford Nuclear Energy Center: Status Report: Conceptual Fuel Cycle Studies for the Hanford Nuclear Energy Center; Selection of Heat Disposal Methods for a Hanford Nuclear Energy Center; Station Service Power Supply for a Hanford Nuclear Energy Center (HNEC); Impact of a Hanford Nuclear Energy Center on Ground Level Fog and Humidity; A Review of Potential Technology for the Seismic Characterization of Nuclear Energy Centers; Reliability of Generation at a Hanford Nuclear Energy Center (HNEC); Meteorological Evaluation of Multiple Reactor Contamination Probabilities for a Hanford Nuclear Energy Center; Electric Power Transmission for a Hanford Nuclear Energy Center (HNEC); The Impact of a Hanford Nuclear Energy Center on Cloudiness and Insolation; and A Licensing Review for an HNEC

  12. Conceptual study

    Energy Technology Data Exchange (ETDEWEB)

    Harty, H.

    1978-09-01

    This appendix is a compendium of topical reports prepared for the Hanford Nuclear Energy Center: Status Report: Conceptual Fuel Cycle Studies for the Hanford Nuclear Energy Center; Selection of Heat Disposal Methods for a Hanford Nuclear Energy Center; Station Service Power Supply for a Hanford Nuclear Energy Center (HNEC); Impact of a Hanford Nuclear Energy Center on Ground Level Fog and Humidity; A Review of Potential Technology for the Seismic Characterization of Nuclear Energy Centers; Reliability of Generation at a Hanford Nuclear Energy Center (HNEC); Meteorological Evaluation of Multiple Reactor Contamination Probabilities for a Hanford Nuclear Energy Center; Electric Power Transmission for a Hanford Nuclear Energy Center (HNEC); The Impact of a Hanford Nuclear Energy Center on Cloudiness and Insolation; and A Licensing Review for an HNEC.

  13. Systems studies

    International Nuclear Information System (INIS)

    The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity, the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the U.S.A. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated Bioenergy Systems (IBS) Activity of IEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the U.S.A. and the U.K. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modelling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from techno-economic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the U.S.A. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review 8 refs, 10 tabs

  14. Systems Studies

    Energy Technology Data Exchange (ETDEWEB)

    Graham, R.L.

    1998-03-17

    The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity; the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the US. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated BioEnergy Systems (TBS) Activity of TEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the US and the UK. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modeling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from technoeconomic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the US. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review.

  15. Full-dimensional control of the radiationless decay in pyrazine using the dynamic Stark effect

    Energy Technology Data Exchange (ETDEWEB)

    Saab, Mohamad, E-mail: mohamad.saab@univ-montp2.fr; Lasorne, Benjamin, E-mail: benjamin.lasorne@univ-montp2.fr; Gatti, Fabien, E-mail: gatti@univ-montp2.fr [CTMM, Institut Charles Gerhardt Montpellier (UMR5253), CC 15001, Université Montpellier 2, F-34095 Montpellier, Cedex 05 (France); Sala, Matthieu; Guérin, Stéphane [Laboratoire Interdisciplinaire Carnot de Bourgogne (UMR 6303) CNRS, Université de Bourgogne, BP 47870, F-21078 Dijon (France)

    2014-10-07

    We present a full quantum-mechanical study of the laser control of the radiationless decay between the B{sub 3u}(nπ{sup *}) and B{sub 2u}(ππ{sup *}) states of pyrazine using the dynamic Stark effect. In contrast to our previous study [Sala et al., J. Chem. Phys. 140, 194309 (2014)], where a four-dimensional model was used, all the 24 degrees of freedom are now included in order to test the robustness of the strategy of control. Using a vibronic coupling Hamiltonian model in a diabatic representation, the multi-layer version of the multi-configuration time-dependent Hartree method is exploited to propagate the corresponding wave packets. We still observe a trapping of the wavepacket on the B{sub 2u}(ππ{sup *}) potential energy surface due to the Stark effect for a longer time than the “non-resonant field-free” B{sub 2u}(ππ{sup *}) lifetime.

  16. Quasi 3D ECE imaging system for study of MHD instabilities in KSTAR

    Energy Technology Data Exchange (ETDEWEB)

    Yun, G. S., E-mail: gunsu@postech.ac.kr; Choi, M. J.; Lee, J.; Kim, M.; Leem, J.; Nam, Y.; Choe, G. H. [Department of Physics, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Lee, W.; Park, H. K. [Ulsan National Institute of Science and Technology, Ulsan 689-798 (Korea, Republic of); Park, H.; Woo, D. S.; Kim, K. W. [School of Electrical Engineering, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Domier, C. W.; Luhmann, N. C. [Department of Electrical and Computer Engineering, University of California, Davis, California 95616 (United States); Ito, N. [KASTEC, Kyushu University, Kasuga-shi, Fukuoka 812-8581 (Japan); Mase, A. [Ube National College of Technology, Ube-shi, Yamaguchi 755-8555 (Japan); Lee, S. G. [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)

    2014-11-15

    A second electron cyclotron emission imaging (ECEI) system has been installed on the KSTAR tokamak, toroidally separated by 1/16th of the torus from the first ECEI system. For the first time, the dynamical evolutions of MHD instabilities from the plasma core to the edge have been visualized in quasi-3D for a wide range of the KSTAR operation (B{sub 0} = 1.7∼3.5 T). This flexible diagnostic capability has been realized by substantial improvements in large-aperture quasi-optical microwave components including the development of broad-band polarization rotators for imaging of the fundamental ordinary ECE as well as the usual 2nd harmonic extraordinary ECE.

  17. Probes of Yukawa unification in supersymmetric SO(10) models

    Energy Technology Data Exchange (ETDEWEB)

    Westhoff, Susanne

    2009-10-23

    This work is composed as follows: In Chapter 1, the disposed reader is made familiar with the foundations of flavourphysics and Grand Unification, including group-theoretical aspects of SO(10). In Chapter 2, we introduce a specific supersymmetric GUT model based on SO(10) and designed to probe down-quark-lepton Yukawa unification. Within this framework we explore the effects of large atmospheric neutrino mixing in bottom-strange transitions on the mass difference and CP phase in B{sub s}- anti B{sub s} meson mixing. Chapter 3 is devoted to corrections to Yukawa unification. We derive constraints on Yukawa corrections for light fermions from K- anti K and B{sub d}- anti B {sub d} mixing. As an application we study implications of neutrino mixing effects in CP-violating K and B{sub d} observables on the unitrity triangle. Finally, in Chapter 4, we discuss effects of large tan {beta} in B{yields}(D){tau}{nu} decays with respect to their potential to discover charged Higgs bosons and to discriminate between different GUT models of flavour.

  18. Measurement of the cp violation parameter sin 2 beta

    Energy Technology Data Exchange (ETDEWEB)

    K.F. Kelley

    1999-01-26

    This thesis presents a measurement of the time-dependent asymmetry in the rate of {anti B}{sub d}{sup 0} versus B{sub d}{sup 0} decays to J/{psi}K{sub s}{sup 0}. In the context of the Standard Model this is interpreted as a measurement of the CP violation parameter sin(2{beta}). A total of 198{+-}17 B{sub d}{sup 0}/{anti B}{sub d}{sup 0} decays were observed in p{anti p} collisions at {radical}s=1.8 TeV by the CDF detector at the Fermilab Tevatron. The initial B flavor (whether B{sup 0} or {anti B}{sup 0}) is determined by a same-side flavor tagging technique. The analysis results in sin(2{beta})=1.8{+-}1.1(stat.){+-}0.3(syst.). This analysis demonstrates the feasibility of studying CP violation in the B{sup 0}-{anti B}{sup 0} system at a hadron collider. By applying the methods used in this analysis, future, higher-statistics experiments should be able to tightly constrain the parameters of the Standard Model.

  19. Contribution of diffusion-weighted MR imaging for predicting benignity of complex adnexal masses

    Energy Technology Data Exchange (ETDEWEB)

    Thomassin-Naggara, Isabelle [Hopital Tenon, Assistance Publique Hopitaux de Pariss, Department of Radiology, Paris (France); Universite Rene Descartes, LRI-EA4062, Paris (France); Darai, Emile [Hopital Tenon, Assistance Publique Hopitaux de Pariss, Department of Gynecology-Obstetrics, Paris (France); Cuenod, Charles A.; Fournier, Laure [Universite Rene Descartes, LRI-EA4062, Paris (France); Hopital Europeen Georges Pompidou (HEGP), Assistance Publique Hopitaux de Paris, Department of Radiology, Paris (France); Toussaint, Irwin; Marsault, Claude; Bazot, Marc [Hopital Tenon, Assistance Publique Hopitaux de Pariss, Department of Radiology, Paris (France)

    2009-06-15

    The purpose of this study was to prospectively assess the contribution of diffusion-weighted MR imaging (DWI) for characterizing complex adnexal masses. Seventy-seven women (22-87 years old) with complex adnexal masses (30 benign and 47 malignant) underwent MR imaging including DWI before surgery. Conventional morphological MR imaging criteria were recorded in addition to b{sub 1,000} signal intensity and apparent diffusion coefficient (ADC) measurements of cystic and solid components. Positive likelihood ratios (PLR) were calculated for predicting benignity and malignancy. The most significant criteria for predicting benignity were low b{sub 1,000} signal intensity within the solid component (PLR = 10.9), low T2 signal intensity within the solid component (PLR = 5.7), absence of solid portion (PLR = 3.1), absence of ascites or peritoneal implants (PLR = 2.3) and absence of papillary projections (PLR = 2.3). ADC measurements did not contribute to differentiating benign from malignant adnexal masses. All masses that displayed simultaneously low signal intensity within the solid component on T2-weighted and on b{sub 1,000} diffusion-weighted images were benign. Alternatively, the presence of a solid component with intermediate T2 signal and high b{sub 1,000} signal intensity was associated with a PLR of 4.5 for a malignant adnexal tumour. DWI signal intensity is an accurate tool for predicting benignity of complex adnexal masses. (orig.)

  20. Electron-irradiation induced changes in structural and magnetic properties of Fe and Co based metallic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Kane, S.N., E-mail: kane_sn@yahoo.com [School of Physics, D.A. University, Khandwa Road Campus, Indore 452001 (India); Satalkar, M., E-mail: satalkar.manvi@gmail.com [School of Physics, D.A. University, Khandwa Road Campus, Indore 452001 (India); Ghosh, A.; Shah, M. [School of Physics, D.A. University, Khandwa Road Campus, Indore 452001 (India); Ghodke, N. [UGC-DAE CSR, University Campus, Khandwa Road, Indore 452001 (India); Pramod, R.; Sinha, A.K.; Singh, M.N.; Dwivedi, J. [Raja Ramanna Centre for Advanced Technology, P.O. CAT, Indore 452013 (India); Coisson, M.; Celegato, F.; Vinai, F.; Tiberto, P. [INRIM, Electromagnetism Division, Strada Delle Cacce 91, I-10135 TO (Italy); Varga, L.K. [RISSPO, Hungarian Academy of Sciences, P.O. Box 49, 1525 Budapest (Hungary)

    2014-12-05

    Highlights: • Enhancement of Ms by low electron irradiation dose in Fe-based alloy. • Variation of magnetic properties by electron irradiation induced ordered phase. • Electron irradiation alters TM-TM distance and, magnetic properties. - Abstract: Electron-irradiation induced changes in structural and, magnetic properties of Co{sub 57.6}Fe{sub 14.4}Si{sub 4.8}B{sub 19.2}Nb{sub 4}, Fe{sub 72}Si{sub 4.8}B{sub 19.2}Nb{sub 4} and, Co{sub 72}Si{sub 4.8}B{sub 19.2}Nb{sub 4} metallic glasses were studied using magnetic hysteresis and, synchrotron X-ray diffraction measurements. Results reveal composition dependent changes of magnetic properties in electron irradiated metallic glasses. A low electron irradiation dose (15 kGy) enhances saturation magnetization (up to 62%) in Fe-based alloy (Fe{sub 72}Si{sub 4.8}B{sub 19.2}Nb{sub 4}). Synchrotron XRD measurements reveal that electron irradiation transforms the amorphous matrix to a more ordered phase, accountable for changes in magnetic properties.

  1. Measurements of Rates, Asymmetries, and Angular Distributions in B -> K l+ l- and B -> K* l+ l- Decays

    Energy Technology Data Exchange (ETDEWEB)

    Hollar, Jonathan; /SLAC /Wisconsin U., Madison

    2006-09-21

    This dissertation describes studies of the rare decays B{sub d} {yields} K{ell}{sup +}{ell}{sup -} and B{sub d} {yields} K*{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either an e{sup +}e{sup -} or a {mu}{sup +}{mu}{sup -} pair. These decays are highly suppressed in the Standard Model, and could be strongly affected by physics beyond the Standard Model. The authors measure the total branching fractions {Beta}(B{sub d} {yields} K{ell}{sup +}{ell}{sup -}) = (0.34 {+-} 0.07 {+-} 0.03) x 10{sup -6}, {Beta}(B{sub d} {yields} K*{ell}{sup +}{ell}{sup -}) = (0.78{sub -0.17}{sup +0.19} {+-} 0.12) x 10{sup -6}. In addition, they measure the partial branching fractions, relative abundance of muons to electrons, direct CP asymmetry, dilepton forward-backward asymmetry, and longitudinal polarization of the K* in these modes. They also search for the lepton flavor-violating decays B{sub d} {yields} Ke{sup {+-}}{mu}{sup {-+}} and B{sub d} {yields} K*e{sup {+-}}{mu}{sup {-+}}. The measurements were performed at the SLAC PEP II storage ring running at the {Upsilon}(4S) resonance.

  2. The Kaon B-parameter in mixed action chiral perturbation theory

    Energy Technology Data Exchange (ETDEWEB)

    Aubin, C.; /Columbia U.; Laiho, Jack; Van de Water, Ruth S.; /Fermilab

    2006-09-01

    We calculate the kaon B-parameter, B{sub K}, in chiral perturbation theory for a partially quenched, mixed action theory with Ginsparg-Wilson valence quarks and staggered sea quarks. We find that the resulting expression is similar to that in the continuum, and in fact has only two additional unknown parameters. At one-loop order, taste-symmetry violations in the staggered sea sector only contribute to flavor-disconnected diagrams by generating an {Omicron}(a{sup 2}) shift to the masses of taste-singlet sea-sea mesons. Lattice discretization errors also give rise to an analytic term which shifts the tree-level value of B{sub K} by an amount of {Omicron}(a{sup 2}). This term, however, is not strictly due to taste-breaking, and is therefore also present in the expression for B{sub K} for pure G-W lattice fermions. We also present a numerical study of the mixed B{sub K} expression in order to demonstrate that both discretization errors and finite volume effects are small and under control on the MILC improved staggered lattices.

  3. Synchrotron X-ray diffraction studies of phase transitions and mechanical properties of nanocrystalline materials at high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Prilliman, Gerald Stephen

    2003-09-01

    The behavior of nanocrystals under extreme pressure was investigated using synchrotron x-ray diffraction. A major part of this investigation was the testing of a prototype synchrotron endstation on a bend magnet beamline at the Advanced Light Source for high pressure work using a diamond anvil cell. The experiments conducted and documented here helped to determine issues of efficiency and accuracy that had to be resolved before the construction of a dedicated ''super-bend'' beamline and endstation. The major conclusions were the need for a cryo-cooled monochromator and a fully remote-controllable pressurization system which would decrease the time to change pressure and greatly reduce the error created by the re-placement of the diamond anvil cell after each pressure change. Two very different types of nanocrystal systems were studied, colloidal iron oxide (Fe{sub 2}O{sub 3}) and thin film TiN/BN. Iron oxide nanocrystals were found to have a transition from the {gamma} to the {alpha} structure at a pressure strongly dependent on the size of the nanocrystals, ranging from 26 GPa for 7.2 nm nanocrystals to 37 GPa for 3.6 nm nanocrystals. All nanocrystals were found to remain in the {alpha} structure even after release of pressure. The transition pressure was also found, for a constant size (5.7 nm) to be strongly dependent on the degree of aggregation of the nanocrystals, increasing from 30 GPa for completely dissolved nanocrystals to 45 GPa for strongly aggregated nanocrystals. Furthermore, the x-ray diffraction pattern of the pressure induced {alpha} phase demonstrated a decrease in intensity for certain select peaks. Together, these observations were used to make a complete picture of the phase transition in nanocrystalline systems. The size dependence of the transition was interpreted as resulting from the extremely high surface energy of the {alpha} phase which would increase the thermodynamic offset and thereby increase the kinetic barrier

  4. Transition metal borides. Synthesis, characterization and superconducting properties

    Energy Technology Data Exchange (ETDEWEB)

    Kayhan, Mehmet

    2013-07-12

    A systematic study was done on the synthesis and superconducting properties of metal rich transition metal borides. Five different binary systems were investigated including the boride systems of niobium, tantalum, molybdenum, tungsten and rhenium. High temperature solid state methods were used in order to synthesize samples of different transition metal borides of the composition M{sub 2}B, MB, M{sub 3}B{sub 2}, MB{sub 2}, and M{sub 2}B{sub 4}. The reactions were carried out in three different furnaces with different sample containers: the electric arc (copper crucible), the high frequency induction furnace (boron nitride, tantalum or glassy carbon crucibles), and the conventional tube furnace (sealed evacuated quartz ampoules). The products obtained were characterized with X-ray powder diffractometry, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Phase analyses and crystal structure refinements using the Rietveld method and based on structure models known from literature were performed. A neutron diffraction measurement was done for W{sub 2}B{sub 4} to allow for a complete crystal structure determination, because of the presence of a heavy element like tungsten and a light element like boron that made it difficult to determine the accurate determination of the boron atom positions and occupancies from X-ray data. A new structure model for W{sub 2}B{sub 4} was proposed. Magnetic measurements in a SQUID magnetometer down to temperatures as low as 1.8 K were performed to several of the products in order to see if the transition metal borides become superconducting at low temperatures, and the results were compared with data from literature. Superconducting properties were found for the following compounds: NbB{sub 2} (T{sub C} = 3.5 K), β-MoB (T{sub C} = 2.4 K), β-WB (T{sub C} = 2.0 K), α-WB (T{sub C} = 4.3 K), W{sub 2}B{sub 4} (T{sub C} = 5.4 K), Re{sub 7}B{sub 3} (T{sub C} = 2.4 K). A relationship between the superconducting properties

  5. Experimental study of a linear/non-linear flux rope

    Energy Technology Data Exchange (ETDEWEB)

    DeHaas, Timothy; Gekelman, Walter; Van Compernolle, Bart [Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States)

    2015-08-15

    Flux ropes are magnetic structures of helical field lines, accompanied by spiraling currents. Commonly observed on the solar surface extending into the solar atmosphere, flux ropes are naturally occurring and have been observed by satellites in the near earth and in laboratory environments. In this experiment, a single flux rope (r = 2.5 cm, L = 1100 cm) was formed in the cylindrical, magnetized plasma of the Large Plasma Device (LaPD, L = 2200 cm, r{sub plasma} = 30 cm, n{sub o} = 10{sup 12 }cm{sup −3}, T{sub e} = 4 eV, He). The flux rope was generated by a DC discharge between an electron emitting cathode and anode. This fixes the rope at its source while allowing it to freely move about the anode. At large currents (I > πr{sup 2}B{sub 0}c/2 L), the flux rope becomes helical in structure and oscillates about a central axis. Under varying Alfven speeds and injection current, the transition of the flux rope from stable to kink-unstable was examined. As it becomes non-linear, oscillations in the magnetic signals shift from sinusoidal to Sawtooth-like, associated with elliptical motion of the flux rope; or the signal becomes intermittent as its current density increases.

  6. Fostering Effective Studying and Study Planning with Study Questions

    Science.gov (United States)

    Wilhelm, Pascal; Pieters, Jules M.

    2007-01-01

    In a course on biological psychology and neuropsychology, study questions were provided that also appeared as test questions in the course exam. This method was introduced to support students in active processing and reproduction of the study texts, and study planning. Data were gathered to test the hypothesis that study question use would be…

  7. Optical phonons in CdGa{sub 2}S{sub 4x}Se{sub 4(1-x)} alloys

    Energy Technology Data Exchange (ETDEWEB)

    Kerimova, T. G., E-mail: taira-kerimova@mail.ru; Abdullaev, N. A.; Mamedova, I. A.; Badalova, Z. I.; Guliev, R. A. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan); Paucar, R.; Wakita, K. [Chiba Institute of Technology (Japan); Mamedov, N. T. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan)

    2013-06-15

    The Raman spectra of CdGa{sub 2}S{sub 4x}Se{sub 4(1-x)} alloys (x = 0.1, 0.2, Horizontal-Ellipsis 0.9) are studied. Both the singlemode and double-mode behavior of optical phonons are observed in CdGa{sub 2}S{sub 4x}Se{sub 4(1-x)} alloys. The observed optical mode at 138 cm{sup -1} is independent of the composition. It seems likely that this mode is the 'breathing mode' and is caused by atomic motion in the anion sublattice relative to vacancies. It is shown that the high-frequency modes of symmetry B{sub 1}(LO, TO) and B{sub 2}(LO, TO) are caused by the in-phase motion of atoms in the anion sublattice along the tetragonal axis c relative to trivalent Ga atoms. The doubly degenerate symmetry modes E{sub 1}(LO, TO) and E{sub 2}(LO, TO) are caused by the in-phase motion of atoms in the anion sublattice relative to trivalent Ga atoms of the cation sublattice in the xy plane (dipole 2Ga-4C), where C is S, Se. The optical symmetry modes B{sub 3}(LO, TO) and B{sub 4}(LO, TO) are associated with the motion of atoms in the anion sublattice relative to Cd atoms along the tetragonal axis c. The doubly degenerate modes E{sub 3}(LO, TO) and E{sub 4}(LO, TO) are associated with the motion of atoms in the anion sublattice relative to Cd atoms (dipole Cd-4C). The low-frequency modes B{sub 5}(LO, TO) and E{sub 5}(LO, TO) are the analogs of acoustic phonons at the edge of the Brillouin zone of sphalerite.

  8. Study of the p+{sup 12}C reaction at energies up to 30 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Masahide; Yamamoto, A.; Yoshioka, S. [Kyushu Univ., Fukuoka (Japan)] [and others

    1998-03-01

    Double differential cross sections of charged-particles emitted in the p+{sup 12}C reaction were measured in the energy region from 14 to 26 MeV. The observed continuous components of emitted protons and {alpha}-particles were analyzed by assuming sequential decay of intermediate reaction products and/or simultaneous breakup process. It was found that the three body simultaneous decay, p+{alpha}+{sup 8}Be, and the sequential decay via p+{sup 12}C{sup *}{sub 3-} and {alpha}+{sup 9}B{sub g.s.} are most important in the proton-induced breakup of {sup 12}C for energies up to 30 MeV. (author)

  9. Case Study: Writing a Journal Case Study

    Science.gov (United States)

    Prud'homme-Genereux, Annie

    2016-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue describes incorporating a journal article into the classroom by first converting it into a case study.

  10. Building Transdisciplinary Environmental Studies

    DEFF Research Database (Denmark)

    Holm, Jesper

    2006-01-01

    Conceptual analytical-methodological conceptualization of crossdisciplinary sustainability studies......Conceptual analytical-methodological conceptualization of crossdisciplinary sustainability studies...

  11. German Studies in America. German Studies Notes.

    Science.gov (United States)

    Sander, Volkmar; Osterle, Heinz D.

    This volume contains two papers, "German Studies in America," by Volkmar Sander, and "Historicism, Marxism, Structuralism: Ideas for German Culture Courses," by Heinz D. Osterle. The first paper discusses the position of German studies in the United States today. The greatest challenge comes from low enrollments; therefore, German departments must…

  12. B mesons phenomenology and lattice QCD; Phenomenologie des mesons B et chromodynamique quantique sur reseau

    Energy Technology Data Exchange (ETDEWEB)

    Blossier, B

    2006-06-15

    We have studied some phenomenological aspects of the B meson physics by using lattice QCD, which is a non perturbative method (based on the first principles of Quantum Field Theory) of computing Green functions of the theory. Pionic couplings g{sub 1} and g{sub 2}, parameterizing the effective chiral Lagrangian which describes interactions between heavy-light mesons and soft pions, have been computed beyond the quenched approximation (at N{sub f} = 2). We have renormalized the operator q-bar{gamma}{sub {mu}}{gamma}{sup 5}q non perturbatively by using chiral Ward identities. We obtain g{sub 1} = 0.4/0.6 and g{sub 2} = -0.1/-0.3. We have estimated from an un-quenched simulation (at N{sub f} = 2) the strange quark mass: the non perturbative renormalisation scheme RI-MOM has been applied. After the matching in the MS scheme the result is m{sub s}(2 GeV) = 101 {+-} 8(-0,+25) MeV. We have proposed a method to calculate on the lattice the Heavy Quark Effective Theory form factors of the semileptonic transitions B {yields} D{sup **} at zero recoil. The renormalisation constant of the operator h-bar{gamma}{sub i}{gamma}{sup 5}D{sub j}h has been computed at one-loop order of the perturbation theory. We obtain {tau}{sub 1/2}(1) = 0.3/0.5 and {tau}{sub 3/2}(1) 0.5/0.7. Eventually the bag parameter B{sub B{sub s}} associated the B{sub s} - B{sub s}-bar mixing amplitude in the Standard Model has been estimated in the quenched approximation by using for the strange quark an action which verifies the chiral symmetry at finite lattice spacing a. Thus systematic errors are significantly reduced in the renormalisation procedure because the spurious mixing of the four-fermion operator h-bar{gamma}{sub {mu}}{sub L}qh-bar{gamma}{sub {mu}}{sub L}q with four-fermion operators of different chirality is absent. The result is B{sub B{sub s}} = 0.92(3). (author)

  13. Electron temperature measurements of FRX-C/LSM

    International Nuclear Information System (INIS)

    The electron temperature T/sub e/ has been measured with Thomson scattering field-reversed configurations (FRCs) on the Los Alamos FRX-C/LSM experiment. FRCs formed and trapped in-situ in the θ-pinch source are studied. These experiments mark the first comprehensive FRC T/sub e/ measurements in over five years with data gathered on over 400 discharges. Measurements are performed at a single point in space and time on each discharge. The Thomson scattering diagnostic consist of a Q-switched ruby laser focused from one end to a point 0.2 m from the axial midplane of the θ-pinch coil and at radius of either 0.00 or 0.10 m. Scattered light is collected, dispersed and detected with a 7-channel, triple-grating polychromator configured to detect light wavelengths between 658 and 692 nm. Photomultiplier currents are measured with gated A/D converters, with plasma background signals recorded 100-ns before and 100-ns after the laser pulse. Electron temperatures are measured at either radial position during the time interval, 10 ≤ t ≤ 70 μs, between FRC formation and the onset of the n = 2 instability which usually terminates the discharge. A variety of plasma conditions have been produced by adjusting three external parameters: the initial deuterium fill pressure p/sub O/; the reversed bias magnetic field B/sub b/; and the external magnetic field B/sub w/. The fill-pressure scan has been performed at B/sub b/ ≅ 60 mT and B/sub w/ ≅ 0.4 T with p/sub o/ set at either 2, 3, 4 or 5 mtorr. The bias-field scan, 37 ≤ B/sub b/ ≤ 95 mT, has been performed at p/sub o/ = 3 mtorr and B/sub w/ ≅ 0.4 T. 7 refs., 3 figs., 3 tabs

  14. Inclusion of electronic polarizability effect in high pressure structural properties of alloy of rare-earth antimonides

    Energy Technology Data Exchange (ETDEWEB)

    Yaduvanshi, Namrata, E-mail: namrata-yaduvanshi@yahoo.com; Kapoor, Shilpa; Singh, Sadhna [High Pressure Research Lab. Department of Physics, Barkatullah University, Bhopal (M.P.) India-462026 (India)

    2015-05-15

    In the present paper, we have investigated the high-pressure structural phase transition of rare-earth antimonides (NdSb and DySb). We studied theoretically the structural properties of alloy of these compounds (NdSb and DySb) by using the three-body potential model with the effect of electronic polarizability (TBIPE{sub P}). These compounds exhibit first order crystallographic phase transition from NaCl (B{sub 1}) to CsCl (B{sub 2}) phase at 17.8 GPa and 22.6 GPa respectively. The study has been extended to mixed crystals and the effect of composition on transition pressure and volume change is investigated. The phase transition pressures and associated volume collapse obtained from present potential model (TBIPE{sub P}) show a good agreement with available experimental data.

  15. Lattice dynamics of {alpha} boron and of boron carbide; Proprietes vibrationnelles du bore {alpha} et du carbure de bore

    Energy Technology Data Exchange (ETDEWEB)

    Vast, N

    1999-07-01

    The atomic structure and the lattice dynamics of {alpha} boron and of B{sub 4}C boron carbide have been studied by Density Functional Theory (D.F.T.) and Density Functional Perturbation Theory (D.F.P.T.). The bulk moduli of the unit-cell and of the icosahedron have been investigated, and the equation of state at zero temperature has been determined. In {alpha} boron, Raman diffusion and infrared absorption have been studied under pressure, and the theoretical and experimental Grueneisen coefficients have been compared. In boron carbide, inspection of the theoretical and experimental vibrational spectra has led to the determination of the atomic structure of B{sub 4}C. Finally, the effects of isotopic disorder have been modeled by an exact method beyond the mean-field approximation, and the effects onto the Raman lines has been investigated. The method has been applied to isotopic alloys of diamond and germanium. (author)

  16. Neutron absorption of Al-Si-Mg-B{sub 4}C composite

    Energy Technology Data Exchange (ETDEWEB)

    Abdullah, Yusof, E-mail: yusofabd@nuclearmalaysia.gov.my; Yusof, Mohd Reusmaazran [Malaysian Nuclear Agency, 43000, Bangi Selangor (Malaysia); Ibrahim, Anis Syukriah; Daud, Abdul Razak [Department of Applied Physics, Faculty of Science & Technology, National University of Malaysia, 43600, Bangi Selangor (Malaysia)

    2016-01-22

    Al-Si-Mg-B{sub 4}C composites containing 2-8 wt% of B{sub 4}C were prepared by stir casting technique. Homogenization treatment was carried out at temperatures of 540°C for 4 houra and followed by ageing at 180°C for 2 houra. Microstructure and phase identification were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD) respectively. Neutron absorption study was investigated using neutron source Am/Be{sup 241}. The result indicated that higher B{sub 4}C content improved the neutron absorption property. Meanwhile homogeneity of the composite was increased by ageing processes. This composite is potential to be used as neutron shielding material especially for nuclear reactor application.

  17. Esophagram (Barium Swallow Study)

    Science.gov (United States)

    ... esophagram is a study that is completed in radiology. The test evaluates the esophagus. The esophagus is ... to wear. The study is completed in a radiology (x-ray/fluoroscopy) room. If a child is ...

  18. 522 Postmarket Surveillance Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The 522 Postmarket Surveillance Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated under section 522 of the...

  19. FEMA DFIRM Study Info

    Data.gov (United States)

    Minnesota Department of Natural Resources — This table contains details about the study such as the study name, datum, projection, etc. There is normally only one record in this table for each Flood Insurance...

  20. Current Research Studies

    Science.gov (United States)

    ... Home > Explore CCFA Research > Current Research Studies Current Research Studies Email Print + Share The Crohn’s & Colitis Foundation ... online. Learn more about CCFA Partners. CCFA Clinical Research Alliance The Clinical Research Alliance is a network ...

  1. Excellence in Social Studies.

    Science.gov (United States)

    Durfee, David A.

    1986-01-01

    Discusses a strategy for unifying and improving the social studies curriculum through an "outcomes sought" approach. Outlines eight measurable qualities students completing social studies should have achieved. Discusses implications of this approach. (LP)

  2. The Study of Algae

    Science.gov (United States)

    Rushforth, Samuel R.

    1977-01-01

    Included in this introduction to the study of algae are drawings of commonly encountered freshwater algae, a summary of the importance of algae, descriptions of the seven major groups of algae, and techniques for collection and study of algae. (CS)

  3. Post-Approval Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The CDRH Post-Approval Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated as a condition of approval of a...

  4. Chemical Industry Bandwidth Study

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2006-12-01

    The Chemical Bandwidth Study provides a snapshot of potentially recoverable energy losses during chemical manufacturing. The advantage of this study is the use of "exergy" analysis as a tool for pinpointing inefficiencies.

  5. Future Circular Collider Study

    CERN Document Server

    Benedikt, Michael

    2014-01-01

    This presentation has been given during the 1st EuCARD-2 annual meeting. It contains: • Motivation & scope • Parameters & design challenges • Study organization, study time line • Preparing global FCC collaboration • Summary

  6. Bioactivity of Na{sub 2}O.CaO.SiO{sub 2}.P{sub 2}O{sub 5} modified glasses

    Energy Technology Data Exchange (ETDEWEB)

    Barrios de Arenas, I. [I.U.T., Caracas (Venezuela). Dept. of Materials Technology; Schattner, C.; Vasquez, M. [Simon Bolivar Univ., Sartenejas (Venezuela). Dept. of Materials Science

    2002-07-01

    Special materials have been developed with properties which allow them to be used where a bone replacement is needed. Research works have been carried out on the bioactivity of ceramics and glasses studying their bond to soft or hard tissues. Hench and co-workers discovered that chemical bonding between a bone and certain glass compositions is possible, so called bioactive glasses, encountering them numerous applications in the repair and reconstruction of diseased and damaged tissue, especially hard one (bone). B{sub 2}O{sub 3} and Al{sub 2}O{sub 3} have been used in bioactive glasses to modify its surface dissolution and durability, melting and forming characteristics; however, Al{sub 2}O{sub 3} in contrast to B{sub 2}O{sub 3} can inhibit bone bonding, being the acceptable amount of alumina a function of the glass composition. The purpose of this work was to study the influence of variable B{sub 2}O{sub 3} / Al{sub 2}O{sub 3} addition on the bioactivity NaO.CaO.SiO{sub 2}.P{sub 2}O{sub 5} glasses, being the formation of the apatite layer on the glasses surface investigated in vitro soaked at different time intervals, using simulated body fluid, an acellular aqueous solution which has similar ion concentration to human blood plasma. The reaction surface was studied using scanning electron microscopy (SEM) and the deposited layer was analysed by EDX line scans using UTW detector. The compositional profiles of the deposited surface and substrate showed a layer rich in calcium and phosphorous characterised in previous works as apatite. This phase has grown in all studied compositions except those with B{sub 2}O{sub 3} / Al{sub 2}O{sub 3} contents higher than 0.55. (orig.)