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Sample records for source sagittarius b2

  1. Far-infrared observations of Sagittarius B2 - reconsideration of source structure

    International Nuclear Information System (INIS)

    Thronson, H.A. Jr.; Harper, D.A.; Yerkes Observatory, Williams Bay, WI)

    1986-01-01

    New moderate-angular-resolution far-infrared observations of the Sagittarius B2 star-forming region are presented, discussed, and compared with recent radio molecular and continuum observations of this source. In contrast to previous analyses, its far-infrared spectrum is interpreted as the result of a massive frigid cloud overlying a more-or-less normal infrared source, a natural explanation for the object's previously-noted peculiarities. The characteristics derived for the obscuring cloud are similar to those found for the W51 MAIN object. Both sources have high sub-millimeter surface brightness, a high ratio of sub-millimeter to far-infrared flux, and numerous regions of molecular maser emission. 28 references

  2. HERSCHEL/HIFI OBSERVATIONS OF HYDROGEN FLUORIDE TOWARD SAGITTARIUS B2(M)

    International Nuclear Information System (INIS)

    Monje, R. R.; Emprechtinger, M.; Phillips, T. G.; Lis, D. C.; Goldsmith, P. F.; Bergin, E. A.; Bell, T. A.; Neufeld, D. A.; Sonnentrucker, P.

    2011-01-01

    Herschel/HIFI observations have revealed the presence of widespread absorption by hydrogen fluoride (HF) J = 1-0 rotational transition, toward a number of Galactic sources. We present observations of HF J = 1-0 toward the high-mass star-forming region Sagittarius B2(M). The spectrum obtained shows a complex pattern of absorption, with numerous features covering a wide range of local standard of rest velocities (-130 to 100 km -1 ). An analysis of this absorption yields HF abundances relative to H 2 of ∼1.3 x 10 -8 , in most velocity intervals. This result is in good agreement with estimates from chemical models, which predict that HF should be the main reservoir of gas-phase fluorine under a wide variety of interstellar conditions. Interestingly, we also find velocity intervals in which the HF spectrum shows strong absorption features that are not present, or are very weak, in spectra of other molecules, such as 13 CO (1-0) and CS (2-1). HF absorption reveals components of diffuse clouds with small extinction that can be studied for the first time. Another interesting observation is that water is significantly more abundant than hydrogen fluoride over a wide range of velocities toward Sagittarius B2(M), in contrast to the remarkably constant H 2 O/HF abundance ratio with average value close to unity measured toward other Galactic sources.

  3. Herschel/HIFI measurements of the ortho/para ratio in water towards Sagittarius B2(M) and W31C

    NARCIS (Netherlands)

    Lis, D. C.; Phillips, T. G.; Goldsmith, P. F.; Neufeld, D. A.; Herbst, E.; Comito, C.; Schilke, P.; Mueller, H. S. P.; Bergin, E. A.; Gerin, M.; Bell, T. A.; Emprechtinger, M.; Black, J. H.; Blake, G. A.; Boulanger, F.; Caux, E.; Ceccarelli, C.; Cernicharo, J.; Coutens, A.; Crockett, N. R.; Daniel, F.; Dartois, E.; De Luca, M.; Dubernet, M. -L.; Encrenaz, P.; Falgarone, E.; Geballe, T. R.; Godard, B.; Giesen, T. F.; Goicoechea, J. R.; Gry, C.; Gupta, H.; Hennebelle, P.; Hily-Blant, P.; Kolos, R.; Krelowski, J.; Joblin, C.; Johnstone, D.; Kazmierczak, M.; Lord, S. D.; Maret, S.; Martin, P. G.; Martin-Pintado, J.; Melnick, G. J.; Menten, K. M.; Monje, R.; Mookerjea, B.; Morris, P.; Murphy, J. A.; Ossenkopf, V.; Pearson, J. C.; Perault, M.; Persson, C.; Plume, R.; Qin, S. -L.; Salez, M.; Schlemmer, S.; Schmidt, M.; Sonnentrucker, P.; Stutzki, J.; Teyssier, D.; Trappe, N.; van der Tak, F. F. S.; Vastel, C.; Wang, S.; Yorke, H. W.; Yu, S.; Zmuidzinas, J.; Boogert, A.; Erickson, N.; Karpov, A.; Kooi, J.; Maiwald, F. W.; Schieder, R.; Zaal, P.

    2010-01-01

    We present Herschel/HIFI observations of the fundamental rotational transitions of ortho- and para-(H2O)-O-16 and (H2O)-O-18 in absorption towards Sagittarius B2(M) and W31C. The ortho/para ratio in water in the foreground clouds on the line of sight towards these bright continuum sources is

  4. Model of the Sgr B2 radio source

    International Nuclear Information System (INIS)

    Gosachinskij, I.V.; Khersonskij, V.K.

    1981-01-01

    The dynamical model of the gas cloud around the radio source Sagittarius B2 is suggested. This model describes the kinematic features of the gas in this source: contraction of the core and rotation of the envelope. The stability of the cloud at the initial stage is supported by the turbulent motion of the gas, turbulence energy dissipates due to magnetic viscosity. This process is occurring more rapidly in the dense core and the core begins to collapse but the envelope remains stable. The parameters of the primary cloud and some parameters (mass, density and size) of the collapse are calculated. The conditions in the core at the moment of its fragmentation into masses of stellar order are established [ru

  5. Exploring Molecular Complexity with Alma (EMoCA): High-Angular Observations of SAGITTARIUS~B2(N) at 3~mm

    Science.gov (United States)

    Müller, Holger S. P.; Belloche, Arnaud; Menten, Karl M.; Garrod, Robin T.

    2015-06-01

    Sagittarius (Sgr for short) B2 is the most massive and luminous star-forming region in our Galaxy, located close to the Galactic Center. We have carried out a molecular line survey with the IRAM~30~m telescope toward its two major sites of star-formation, Sgr~B2(M) and (N). Toward the latter source, which is particularly rich in Complex Organic Molecules (COMs), we detected three molecules for the first time in space, aminoacetonitrile, ethyl formate, and n}-propyl cyanide. We have recently obtained ALMA data of Sgr~B2(N) between ˜84 and ˜111~GHz within Cycle~0 and one additional setup up to 114.4~GHz within Cycle~1. At angular resolutions of 1.8'' and 1.4'', respectively, the two main hot cores, the prolific Sgr~B2(N-LMH) (or Sgr~B2(N)-SMA1) and the likely less evolved Sgr~B2(N)-SMA2 are well separated, and line confusion is reduced greatly for the latter. As a consequence, we have been able to identify the first branched alkyl molecule in space, iso-propyl cyanide, toward Sgr~B2(N)-SMA2. Our ongoing analyses include investigations of cyanides and isocyanides, alkanols and thioalkanols, and deuterated molecules among others. We will present some of our results. A. Belloche et al., A&A 559 (2013) Art. No. A47. A. Belloche et al., Science 345 (2014) 1584.

  6. Herschel observations of extraordinary sources: Analysis of the full Herschel/HIFI molecular line survey of sagittarius B2(N)

    Energy Technology Data Exchange (ETDEWEB)

    Neill, Justin L.; Bergin, Edwin A.; Crockett, Nathan R.; Favre, Cécile; Anderson, Dana E.; Burkhardt, Andrew M.; McNeill, Trevor D. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Lis, Dariusz C.; Emprechtinger, Martin; Monje, Raquel R.; Phillips, Thomas G. [California Institute of Technology, Cahill Center for Astronomy and Astrophysics 301-17, Pasadena, CA 91125 (United States); Schilke, Peter; Comito, Claudia; Qin, Sheng-Li [Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, D-50937 Köln (Germany); Chen, Jo-Hsin [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Harris, Brent J.; Steber, Amanda L.; Vasyunina, Tatiana [Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, VA 22904 (United States); Lord, Steven D. [National Herschel Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); McGuire, Brett A., E-mail: jneill@umich.edu, E-mail: ebergin@umich.edu [Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 (United States); and others

    2014-07-01

    A sensitive broadband molecular line survey of the Sagittarius B2(N) star-forming region has been obtained with the Heterodyne Instrument for the Far-Infrared (HIFI) instrument on the Herschel Space Observatory, offering the first high spectral resolution look at this well-studied source in a wavelength region largely inaccessible from the ground (625-157 μm). From the roughly 8000 spectral features in the survey, a total of 72 isotopologues arising from 44 different molecules have been identified, ranging from light hydrides to complex organics, and arising from a variety of environments from cold and diffuse to hot and dense gas. We present a local thermodynamic equilibrium (LTE) model to the spectral signatures of each molecule, constraining the source sizes for hot core species with complementary Submillimeter Array interferometric observations and assuming that molecules with related functional group composition are cospatial. For each molecule, a single model is given to fit all of the emission and absorption features of that species across the entire 480-1910 GHz spectral range, accounting for multiple temperature and velocity components when needed to describe the spectrum. As with other HIFI surveys toward massive star-forming regions, methanol is found to contribute more integrated line intensity to the spectrum than any other species. We discuss the molecular abundances derived for the hot core where the LTE approximation is generally found to describe the spectrum well, in comparison to abundances derived for the same molecules in the Orion KL region from a similar HIFI survey. Notably, we find significantly higher abundances of amine- and amide-bearing molecules (CH{sub 3}NH{sub 2}, CH{sub 2}NH, and NH{sub 2}CHO) toward Sgr B2(N) than Orion KL and lower abundances of some complex oxygen-bearing molecules (CH{sub 3}OCHO in particular). In addition to information on the chemical composition of the hot core, the strong far-infrared dust continuum allows

  7. DETECTION OF E-CYANOMETHANIMINE TOWARD SAGITTARIUS B2(N) IN THE GREEN BANK TELESCOPE PRIMOS SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Zaleski, Daniel P.; Seifert, Nathan A.; Steber, Amanda L.; Muckle, Matt T.; Loomis, Ryan A.; Vasquez, David; Nyiramahirwe, Jolie; Sciortino, Nicole; Johnson, Kennedy; Pate, Brooks H. [Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, VA 22904 (United States); Corby, Joanna F. [Department of Astronomy, University of Virginia, McCormick Road, Charlottesville, VA 22904 (United States); Martinez, Oscar Jr.; Crabtree, Kyle N.; McCarthy, Michael C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Jewell, Philip R.; Remijan, Anthony J. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475 (United States); Hollis, Jan M. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Lovas, Frank J., E-mail: bp2k@virginia.edu, E-mail: mccarthy@cfa.harvard.edu, E-mail: aremijan@nrao.edu [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States)

    2013-03-01

    The detection of E-cyanomethanimine (E-HNCHCN) toward Sagittarius B2(N) is made by comparing the publicly available Green Bank Telescope (GBT) PRIMOS survey spectra to laboratory rotational spectra from a reaction product screening experiment. The experiment uses broadband molecular rotational spectroscopy to monitor the reaction products produced in an electric discharge source using a gas mixture of NH{sub 3} and CH{sub 3}CN. Several transition frequency coincidences between the reaction product screening spectra and previously unassigned interstellar rotational transitions in the PRIMOS survey have been assigned to E-cyanomethanimine. A total of eight molecular rotational transitions of this molecule between 9 and 50 GHz are observed with the GBT. E-cyanomethanimine, often called the HCN dimer, is an important molecule in prebiotic chemistry because it is a chemical intermediate in proposed synthetic routes of adenine, one of the two purine nucleobases found in DNA and RNA. New analyses of the rotational spectra of both E-cyanomethanimine and Z-cyanomethanimine that incorporate previous millimeter-wave measurements are also reported.

  8. DETECTION OF E-CYANOMETHANIMINE TOWARD SAGITTARIUS B2(N) IN THE GREEN BANK TELESCOPE PRIMOS SURVEY

    International Nuclear Information System (INIS)

    Zaleski, Daniel P.; Seifert, Nathan A.; Steber, Amanda L.; Muckle, Matt T.; Loomis, Ryan A.; Vasquez, David; Nyiramahirwe, Jolie; Sciortino, Nicole; Johnson, Kennedy; Pate, Brooks H.; Corby, Joanna F.; Martinez, Oscar Jr.; Crabtree, Kyle N.; McCarthy, Michael C.; Jewell, Philip R.; Remijan, Anthony J.; Hollis, Jan M.; Lovas, Frank J.

    2013-01-01

    The detection of E-cyanomethanimine (E-HNCHCN) toward Sagittarius B2(N) is made by comparing the publicly available Green Bank Telescope (GBT) PRIMOS survey spectra to laboratory rotational spectra from a reaction product screening experiment. The experiment uses broadband molecular rotational spectroscopy to monitor the reaction products produced in an electric discharge source using a gas mixture of NH 3 and CH 3 CN. Several transition frequency coincidences between the reaction product screening spectra and previously unassigned interstellar rotational transitions in the PRIMOS survey have been assigned to E-cyanomethanimine. A total of eight molecular rotational transitions of this molecule between 9 and 50 GHz are observed with the GBT. E-cyanomethanimine, often called the HCN dimer, is an important molecule in prebiotic chemistry because it is a chemical intermediate in proposed synthetic routes of adenine, one of the two purine nucleobases found in DNA and RNA. New analyses of the rotational spectra of both E-cyanomethanimine and Z-cyanomethanimine that incorporate previous millimeter-wave measurements are also reported.

  9. Weak maser emission of methyl formate toward Sagittarius B2(N) in the green bank telescope PRIMOS survey

    Energy Technology Data Exchange (ETDEWEB)

    Faure, A.; Wiesenfeld, L. [UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d' Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble F-38041 (France); Remijan, A. J. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Szalewicz, K. [Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)

    2014-03-10

    A non-LTE radiative transfer treatment of cis-methyl formate (HCOOCH{sub 3}) rotational lines is presented for the first time using a set of theoretical collisional rate coefficients. These coefficients have been computed in the temperature range 5-30 K by combining coupled-channel scattering calculations with a high accuracy potential energy surface for HCOOCH{sub 3}-He. The results are compared to observations toward the Sagittarius B2(N) molecular cloud using the publicly available PRIMOS survey from the Green Bank Telescope. A total of 49 low-lying transitions of methyl formate, with upper levels below 25 K, are identified. These lines are found to probe a presumably cold (∼30 K), moderately dense (∼10{sup 4} cm{sup –3}), and extended region surrounding Sgr B2(N). The derived column density of ∼4 × 10{sup 14} cm{sup –2} is only a factor of ∼10 larger than the column density of the trans conformer in the same source. Provided that the two conformers have the same spatial distribution, this result suggests that strongly non-equilibrium processes must be involved in their synthesis. Finally, our calculations show that all detected emission lines with a frequency below 30 GHz are (collisionally pumped) weak masers amplifying the continuum of Sgr B2(N). This result demonstrates the importance and generality of non-LTE effects in the rotational spectra of complex organic molecules at centimeter wavelengths.

  10. Exploring molecular complexity with ALMA (EMoCA): Detection of three new hot cores in Sagittarius B2(N)

    Science.gov (United States)

    Bonfand, M.; Belloche, A.; Menten, K. M.; Garrod, R. T.; Müller, H. S. P.

    2017-08-01

    Context. The Sagittarius B2 molecular cloud contains several sites forming high-mass stars. Sgr B2(N) is one of its main centers of activity. It hosts several compact and ultra-compact HII regions, as well as two known hot molecular cores (Sgr B2(N1) and Sgr B2(N2)) in the early stage of the high-mass star formation process, where complex organic molecules (COMs) are detected in the gas phase. Aims: Our goal is to use the high sensitivity of the Atacama Large Millimeter/submillimeter Array (ALMA) to characterize the hot core population in Sgr B2(N) and thereby shed new light on the star formation process in this star-forming region. Methods: We use a complete 3 mm spectral line survey conducted with ALMA to search for faint hot cores in the Sgr B2(N) region. The chemical composition of the detected sources and the column densities are derived by modeling the whole spectra under the assumption of local thermodynamic equilibrium. Population diagrams are constructed to fit rotational temperatures. Integrated intensity maps are produced to derive the peak position and fit the size of each molecule's emission distribution. The kinematic structure of the hot cores is investigated by analyzing the line wing emission of typical outflow tracers. The H2 column densities are computed from ALMA and SMA continuum emission maps. Results: We report the discovery of three new hot cores in Sgr B2(N) that we call Sgr B2(N3), Sgr B2(N4), and Sgr B2(N5). The three sources are associated with class II methanol masers, well known tracers of high-mass star formation, and Sgr B2(N5), also with a UCHII region. Their H2 column densities are found to be between approximately 16 and 36 times lower than the one of the main hot core Sgr B2(N1). The spectra of these new hot cores have spectral line densities of 11 up to 31 emission lines per GHz above the 7σ level, assigned to 22-25 molecules plus 13-20 less abundant isotopologs. We derive rotational temperatures of approximately 140-180 K for

  11. SELECTING SAGITTARIUS: IDENTIFICATION AND CHEMICAL CHARACTERIZATION OF THE SAGITTARIUS STREAM

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, E. A. [University of Western Sydney, Locked Bag 1797, Penrith South DC, NSW 1797 (Australia); Keller, S. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2601 (Australia); Zucker, D. B. [Macquarie University, Physics and Astronomy, NSW 2109 (Australia); Ibata, R.; Siebert, A. [Observatoire astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, F-67000 Strasbourg (France); Lewis, G. F.; Conn, A. R. [Sydney Institute for Astronomy, School of Physics, The University of Sydney, NSW 2006 (Australia); Penarrubia, J. [ROE, The University of Edinburgh, Institute for Astronomy, Edinburgh EH9 3HJ (United Kingdom); Irwin, M.; Gilmore, G. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Lane, R. R. [Departamento de Astronomía Universidad de Concepción, Casilla 160 C, Concepción (Chile); Koch, A. [Landessternwarte, Zentrum für Astronomie der Universität Heidelberg, Königstuhl 12, D-69117 Heidelberg (Germany); Diakogiannis, F. I. [International Center for Radio Astronomy Research, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia); Martell, S., E-mail: E.Hyde@uws.edu.au [Department of Astrophysics, School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia)

    2015-06-01

    Wrapping around the Milky Way, the Sagittarius stream is the dominant substructure in the halo. Our statistical selection method has allowed us to identify 106 highly likely members of the Sagittarius stream. Spectroscopic analysis of metallicity and kinematics of all members provides us with a new mapping of the Sagittarius stream. We find correspondence between the velocity distribution of stream stars and those computed for a triaxial model of the Milky Way dark matter halo. The Sagittarius trailing arm exhibits a metallicity gradient, ranging from −0.59 to −0.97 dex over 142°. This is consistent with the scenario of tidal disruption from a progenitor dwarf galaxy that possessed an internal metallicity gradient. We note high metallicity dispersion in the leading arm, causing a lack of detectable gradient and possibly indicating orbital phase mixing. We additionally report on a potential detection of the Sextans dwarf spheroidal in our data.

  12. RED CLUMP STARS IN THE SAGITTARIUS TIDAL STREAMS

    International Nuclear Information System (INIS)

    Carrell, Kenneth; Chen Yuqin; Wilhelm, Ronald

    2012-01-01

    We have probed a section (l ∼ 150, b ∼ –60) of the trailing tidal arm of the Sagittarius dwarf spheroidal galaxy by identifying a sample of Red Clump (RC) stream stars. RC stars are not generally found in the halo field, but are found in significant numbers in both the Sagittarius galaxy and its tidal streams, making them excellent probes of stream characteristics. Our target sample was selected using photometric data from the Sloan Digital Sky Survey, Data Release 6, which was constrained in color to match the Sagittarius RC stars. Spectroscopic observations of the target stars were conducted at Kitt Peak National Observatory using the WIYN telescope. The resulting spectroscopic sample is magnitude limited and contains both main-sequence disk stars and evolved RC stars. We have developed a method to systematically separate these two stellar classes using kinematic information and a Bayesian approach for surface gravity determination. The resulting RC sample allows us to determine an absolute stellar density of ρ = 2.7 ± 0.5 RC stars kpc –3 at this location in the stream. Future measurements of stellar densities for a variety of populations and at various locations along the streams will lead to a much improved understanding of the original nature of the Sagittarius galaxy and the physical processes controlling its disruption and subsequent stream generation.

  13. Exploring molecular complexity with ALMA (EMoCA): Deuterated complex organic molecules in Sagittarius B2(N2)

    Science.gov (United States)

    Belloche, A.; Müller, H. S. P.; Garrod, R. T.; Menten, K. M.

    2016-03-01

    Context. Deuteration is a powerful tracer of the history of the cold prestellar phase in star-forming regions. Apart from methanol, little is known about deuterium fractionation of complex organic molecules in the interstellar medium, especially in regions forming high-mass stars. Aims: Our goal is to detect deuterated complex organic molecules toward the high mass star-forming region Sagittarius B2 (Sgr B2) and derive the level of deuteration for these molecules. Methods: We use a complete 3-mm spectral line survey performed with the Atacama Large Millimeter/submillimeter Array (ALMA) to search for deuterated complex organic molecules toward the hot molecular core Sgr B2(N2). We constructed population diagrams and integrated intensity maps to fit rotational temperatures and emission sizes for each molecule. Column densities are derived by modeling the full spectrum under the assumption of local thermodynamic equilibrium. We compare the results to predictions of two astrochemical models that treat the deuteration process. Results: We report the detection of CH2DCN toward Sgr B2(N2) with a deuteration level of 0.4%, and tentative detections of CH2DOH, CH2DCH2CN, the chiral molecule CH3CHDCN, and DC3N with levels in the range 0.05%-0.12%. A stringent deuteration upper limit is obtained for CH3OD (cyanide, the four deuterated species of ethanol, and CH2DOCHO. Ethyl cyanide is less deuterated than methyl cyanide by at least a factor five. The [CH2DOH]/[CH3OD] abundance ratio is higher than 1.8. It may still be consistent with the value obtained in Orion KL. Except for methyl cyanide, the measured deuteration levels lie at least a factor four below the predictions of current astrochemical models. The deuteration levels in Sgr B2(N2) are also lower than in Orion KL by a factor of a few up to a factor ten. Conclusions: The discrepancy between the deuteration levels of Sgr B2(N2) and the predictions of chemical models, and the difference between Sgr B2(N2) and Orion KL may

  14. 1300 micron continuum observations of the Sagittarius B2 molecular cloud core

    International Nuclear Information System (INIS)

    Goldsmith, P.F.; Snell, R.L.; Lis, D.C.

    1987-01-01

    Observations with 23-arcsec angular resolution are obtained of the continuum emission at 1300 microns wavelength from the central region of the Sgr B2 molecular cloud, which contains the north and middle high-mass star-forming regions and associated radio continuum and maser sources. The spatial resolution of the present data shows that the 1300-micron continuum emission peak is located at Sgr B2(N), in contrast to the midinfrared emission, which is centered on Sgr B2(M). Comparison with 53 micron data having comparable angular resolution suggests that there is optically thick foreground dust which prevents detection of Sgr B2(N) at wavelengths not greater than 100 microns. Within the about 1.5 x 3.5 pc region mapped, the total mass is 500,000 solar masses and the mean H2 density is 300,000/cu cm, somewhat larger than found in previous investigations. 27 references

  15. Sagittarius Dwarf Galaxy

    Science.gov (United States)

    Ibata, R.; Murdin, P.

    2000-11-01

    The Sagittarius DWARF GALAXY is the closest member of the Milky Way's entourage of satellite galaxies. Discovered by chance in 1994, its presence had previously been overlooked because it is largely hidden by the most crowded regions of our own Galaxy with which it is merging....

  16. Molecular and Recombination Lines in the Central Region of Sagittarius B2

    Science.gov (United States)

    Curtis, J.; Langston, G.

    2005-12-01

    We present observations of recombination and molecular lines towards Sgr B2 in the frequency range 12.4 to 15.0 GHz. In this frequency range, Hα , β , and γ lines, Heα recombination lines and emission from the SO molecule are detected. Molecular absorption lines from OH, H2CO, and CH3CO are detected at velocity 62±3 km/s. Measurements of the line widths and intensities are presented for the central region of Sgr B2. We detect two previously un-reported molecular absorption lines at 12388.0 and 14625.8 MHz (v=0. in LSR Frame). For selected recombination and molecular lines, we present images of a 10x10 arc-minute region centered on Sgr B2(M). We discuss the sources of three H2CO absorption features detected at 62±3, 6±5, and 100±10 km/s. This was done as a summer REU project in 2005 at the National Radio Astronomy Observatory's Green Bank site, and was funded by the National Science Foundation's REU program.

  17. Macho project photometry of RR Lyrae stars in the Sagittarius dwarf galaxy

    Energy Technology Data Exchange (ETDEWEB)

    Alcock, C. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)]|[Center for Particle Astrophysics, University of California, Berkeley, California 94720 (United States); Allsman, R.A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)]|[Mount Stromlo and Siding Spring Observatories, Australian National University, Weston, ACT 2611 (Australia); Alves, D.R. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)]|[Department of Physics, University of California, Davis, California 95616 (United States); Axelrod, T.S. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)]|[Mount Stromlo and Siding Spring Observatories, Australian National University, Weston, ACT 2611 (Australia); Becker, A.C. [Center for Particle Astrophysics, University of California, Berkeley, California 94720 (United States)]|[Department of Astronomy, University of Washington, Seattle, Washington 98195 (United States); Bennett, D.P.; Cook, K.H. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)]|[Center for Particle Astrophysics, University of California, Berkeley, California 94720 (United States); Freeman, K.C. [Mount Stromlo and Siding Spring Observatories, Australian National University, Weston, ACT 2611 (Australia); Griest, K. [Center for Particle Astrophysics, University of California, Berkeley, California 94720 (United States)]|[Department of Physics, University of California, San Diego, California 92093 (United States); Guern, J.A.; Lehner, M.J. [Department of Physics, University of California, San Diego, California 92093 (United States); Marshall, S.L.; Minniti, D. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Peterson, B.A. [Mount Stromlo and Siding Spring Observatories, Australian National University, Weston, ACT 2611 (Australia); Pratt, M.R.

    1997-01-01

    We report the discovery of 30 type a, b RR Lyrae (RRab) stars that are likely members of the Sagittarius dwarf galaxy (Sgr). Accurate positions, periods, amplitudes, and magnitudes are presented. Their distances are determined with respect to RRab stars in the Galactic bulge found also in the MACHO 1993 data. For R{sub {circle_dot}}=8kpc, the mean distance to these stars is D=22{plus_minus}1kpc, smaller than previous determinations for this galaxy. This indicates that Sgr has an elongated main body extending for more than 10 kpc, which is inclined along the line of sight, with its northern part (in Galactic coordinates) closer to us. The size and shape of Sgr give clues about the past history of this galaxy. If the shape of Sgr follows the direction of its orbit, the observed spatial orientation suggests that Sgr is moving away from the Galactic plane. Also, Sgr stars may be the sources of some of the microlensing events seen toward the bulge. {copyright} {ital 1997} {ital The American Astronomical Society}

  18. NuSTAR detection of high-energy X-ray emission and rapid variability from sagittarius A* flares

    DEFF Research Database (Denmark)

    Barrière, Nicolas M.; Tomsick, John A.; Baganoff, Frederick K.

    2014-01-01

    Sagittarius A* harbors the supermassive black hole that lies at the dynamical center of our Galaxy. Sagittarius A* spends most of its time in a low luminosity emission state but flares frequently in the infrared and X-ray, increasing up to a few hundred fold in brightness for up to a few hours at...

  19. Detecting Changing Polarization Structures in Sagittarius A* with High Frequency VLBI

    Science.gov (United States)

    Fish, Vincent L.; Doeleman, Sheperd S.; Broderick, Avery E.; Loeb, Abraham; Rogers, Alan E. E.

    2009-12-01

    Sagittarius A* is the source of near infrared, X-ray, radio, and (sub)millimeter emission associated with the supermassive black hole at the Galactic Center. In the submillimeter regime, Sgr A* exhibits time-variable linear polarization on timescales corresponding to errors. Although the source-integrated linear polarization fraction in the models is typically only a few percent, the linear polarization fraction on small angular scales can be much higher, enabling the detection of changes in the polarimetric structure of Sgr A* on a wide variety of baselines. The shortest baselines track the source-integrated linear polarization fraction, while longer baselines are sensitive to polarization substructures that are beam-diluted by connected-element interferometry. The detection of periodic variability in source polarization should not be significantly affected even if instrumental polarization terms cannot be calibrated out. As more antennas are included in the (sub)millimeter-VLBI array, observations with full polarization will provide important new diagnostics to help disentangle intrinsic source polarization from Faraday rotation effects in the accretion and outflow region close to the black hole event horizon.

  20. Three millimeter molecular line observations in Sagittarius B2. 1: Full synthesis mapping study of HNO, CCS, and HC(13)CCN

    Science.gov (United States)

    Kuan, Yi-Jehng; Snyder, Lewis E.

    1994-01-01

    We present the first full synthesis maps of the small molecules HNO, CCS, and HC(13)CCN in Sgr B2. We have observed the 3.8 mm continuum, the HNO J(sub K(sub -1)K(sub 1)) = 1(sub O1)-0(sub OO), the CCS J(sub N) = 7(sub 6)-6(sub 5), and the HC(13)CCN J = 9-8 transitions in the core of the Sgr B2 molecular cloud, using the Berkeley Illinois Maryland Association (BIMA) millimeter array and the NRAO 12 m telescope. We have found that HNO exists in five major gas clumps in the Sgr B2 region, which we have labeled HNO(N), HNO(NW), HNO(E), HNO(M), and HNO(S). Of particular interest is HNO(M), a major molecular gas concentration approximately 15 sec west of Sgr B2(M) in a region of young star formation. HNO is found to be closely associated with the ionized gas and might be depleted around bright H II complexes. In general, the peak intensity of the HNO emission is found to be offset from the peak of the continuum emission. We found evidence for some chemical differentiation among the three species, HNO, CCS, and HC(13)CCN, but the abundance ratios are in fair agreement with theoretical models. Two unidentified lines, U81420 and U81518, were observed, and a previously unknown compact dust source was detected. Our HNO data indicate the presence of a rotating approximately (2.2-4.4) x 10(exp 3)solar mass gas envelope surrounding Sgr B2(N), a possible bipolar gas outflow in HNO(M), and possibly a large (approximately 4.2 x 10(exp 4)solar mass) extended rotating disk associated with HNO(S). In addition, the CCS and HC(13)CCN data approximately outline the extended component of Sgr B2 and clearly show that the southern continuum source Sgr B2(S) is actually a major molecular source as well. Consequently, the kinematics of the Sgr B2 molecular cloud is quite complex, but in moving from the northwest to south, the LSR velocity generally changes from 79 to 46 km/s.

  1. Symbolics of the constellations of sagittarius and centaurus in russian traditional culture

    Science.gov (United States)

    Bagdasarov, R.

    2001-12-01

    Centaurus falls into the category of 'imaginary animals'. The Russian tradition used not only the symbol Sgr (a result of its acquaintance with the circle of Zodiac), but also the symbol Cen, which fact, as we shall demonstrate, is an evidence of certain mythological-astronomical conceptions. Both the constellations Sagittarius (Sgr) and Centaurus (Cen) are usually represented as versions of the picture of a fantastic being, a Centaur, shaped as man from head to waist, and as an animal, mostly, a horse, from waist down. 'Centaurus' (from the Greek word kev (or kevw)) for 'kill' and o, for 'bull') means 'bull killer', and is probably related to the opposition of the zodiacal constellations Taurus and Sagittarius. When the latter begins to rise on to the night sky, the former disappears completely from view. Sagittarius is represented at ancient monuments related to astronomy as a centaur holding a bow and pointing at certain stars. The constellation of Centaurus is also symbolised by a centaur, but holding not a bow, but a staff or a spear in one hand and an 'animal of sacrifice' in the other (Higinus, Astronomica, III, 37, 1; Chernetsov, 1975, Figure 1). The attributes stand for the Peliases Spear (The Mithological Dictionary, 1991), depicted in astrological maps as The Spear of Centaurus1, The Wolf (Lupus), the Panther or the Beast (Flammarion, 1994).

  2. Atomic Oxygen Abundance in Molecular Clouds: Absorption Toward Sagittarius B2

    Science.gov (United States)

    Lis, D. C.; Keene, Jocelyn; Phillips, T. G.; Schilke, P.; Werner, M. W.; Zmuidzinas, J.

    2001-01-01

    We have obtained high-resolution (approximately 35 km/s) spectra toward the molecular cloud Sgr B2 at 63 micrometers, the wavelength of the ground-state fine-structure line of atomic oxygen (O(I)), using the ISO-LWS instrument. Four separate velocity components are seen in the deconvolved spectrum, in absorption against the dust continuum emission of Sgr B2. Three of these components, corresponding to foreground clouds, are used to study the O(I) content of the cool molecular gas along the line of sight. In principle, the atomic oxygen that produces a particular velocity component could exist in any, or all, of three physically distinct regions: inside a dense molecular cloud, in the UV illuminated surface layer (PDR) of a cloud, and in an atomic (H(I)) gas halo. For each of the three foreground clouds, we estimate, and subtract from the observed O(I) column density, the oxygen content of the H(I) halo gas, by scaling from a published high-resolution 21 cm spectrum. We find that the remaining O(I) column density is correlated with the observed (13)CO column density. From the slope of this correlation, an average [O(I)]/[(13)CO] ratio of 270 +/- 120 (3-sigma) is derived, which corresponds to [O(I)]/[(13)CO] = 9 for a CO to (13)CO abundance ratio of 30. Assuming a (13)CO abundance of 1x10(exp -6) with respect to H nuclei, we derive an atomic oxygen abundance of 2.7x10(exp -4) in the dense gas phase, corresponding to a 15% oxygen depletion compared to the diffuse ISM in our Galactic neighborhood. The presence of multiple, spectrally resolved velocity components in the Sgr B2 absorption spectrum allows, for the first time, a direct determination of the PDR contribution to the O(I) column density. The PDR regions should contain O(I) but not (13)CO, and would thus be expected to produce an offset in the O(I)-(13)CO correlation. Our data do not show such an offset, suggesting that within our beam O(I) is spatially coexistent with the molecular gas, as traced by (13)CO

  3. Coordinated mm/sub-mm observations of Sagittarius A* in May 2007

    Energy Technology Data Exchange (ETDEWEB)

    Kunneriath, D; Eckart, A; Bertram, T; Konig, S [University of Cologne, Zuelpicher Str. 77, D-50937 Cologne (Germany); Vogel, S [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Sjouwerman, L [National Radio Astronomy Observatory, PO Box 0, Socorro, NM 87801 (United States); Wiesemeyer, H [IRAM, Avenida Divina Pastora, 7, Nuecleo Central, E-18012 Granada (Spain); Schoedel, R [Instituto de AstrofIsica de AndalucIa, Camino Bajo de Huetor 50, 18008 Granada (Spain); Baganoff, F K [Center for Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139-4307 (United States); Morris, M; Mauerhan, J; Meyer, L [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States); Dovciak, M; Karas, V [Astronomical Institute, Academy of Sciences, BocnI II, CZ-14131 Prague (Czech Republic); Dowries, D [Institut de Radio Astronomie Millimetrique, Domaine Universitaire, 38406 St. Martin d' Heres (France); Krichbaum, T; Lu, R-S [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, 53121 Bonn (Germany); Krips, M [Harvard-Smithsonian Center for Astrophysics, SMA project, 60 Garden Street, MS 78 Cambridge, MA 02138 (United States); Markoff, S [Astronomical Institute ' Anton Pannekoek' , University of Amsterdam, Kruislaan 403, 1098SJ Amsterdam (Netherlands); Duschl, W J, E-mail: eckart@phl.uni-koeln.de (and others)

    2008-10-15

    At the center of the Milky Way, with a distance of {approx}8 kpc, the compact source Sagittarius A* (SgrA*) can be associated with a super massive black hole of {approx}4x 10{sup 6}M{sub o-dot}. SgrA* shows strong variability from the radio to the X-ray wavelength domains. Here we report on simultaneous NIR/sub-millimeter/X-ray observations from May 2007 that involved the NACO adaptive optics (AO) instrument at the European Southern Observatory's Very Large Telescope, the Australian Telescope Compact Array (ATCA), the US mm-array CARMA, the IRAM 30m mm-telescope, and other telescopes. We concentrate on the time series of mm/sub-mm data from CARMA, ATCA, and the MAMBO bolometer at the IRAM 30m telescope.

  4. DETECTING FLARING STRUCTURES IN SAGITTARIUS A* WITH HIGH-FREQUENCY VLBI

    International Nuclear Information System (INIS)

    Doeleman, Sheperd S.; Fish, Vincent L.; Rogers, Alan E. E.; Broderick, Avery E.; Loeb, Abraham

    2009-01-01

    The super-massive black hole candidate, Sagittarius A*, exhibits variability from radio to X-ray wavelengths on timescales that correspond to <10 Schwarzschild radii. We survey the potential of millimeter wavelength very long baseline interferometry (VLBI) to detect and constrain time-variable structures that could give rise to such variations, focusing on a model in which an orbiting hot spot is embedded in an accretion disk. Nonimaging algorithms are developed that use interferometric closure quantities to test for periodicity, and applied to an ensemble of hot spot models that sample a range of parameter space. We find that structural periodicity in a wide range of cases can be detected on most potential VLBI arrays using modern VLBI instrumentation. Future enhancements of millimeter/submillimeter VLBI arrays including phased-array processors to aggregate VLBI station collecting area, increased bandwidth recording, and addition of new VLBI sites all significantly aid periodicity detection. The methods described herein can be applied to other models of Sagittarius A*, including jet outflows and magnetohydrodynamic accretion simulations.

  5. PERSISTENT ASYMMETRIC STRUCTURE OF SAGITTARIUS A* ON EVENT HORIZON SCALES

    International Nuclear Information System (INIS)

    Fish, Vincent L.; Doeleman, Sheperd S.; Lu, Ru-Sen; Akiyama, Kazunori; Beaudoin, Christopher; Cappallo, Roger; Johnson, Michael D.; Blackburn, Lindy; Blundell, Ray; Chael, Andrew A.; Broderick, Avery E.; Psaltis, Dimitrios; Chan, Chi-Kwan; Alef, Walter; Bertarini, Alessandra; Algaba, Juan Carlos; Asada, Keiichi; Bower, Geoffrey C.; Brinkerink, Christiaan; Chamberlin, Richard

    2016-01-01

    The Galactic Center black hole Sagittarius A* (Sgr A*) is a prime observing target for the Event Horizon Telescope (EHT), which can resolve the 1.3 mm emission from this source on angular scales comparable to that of the general relativistic shadow. Previous EHT observations have used visibility amplitudes to infer the morphology of the millimeter-wavelength emission. Potentially much richer source information is contained in the phases. We report on 1.3 mm phase information on Sgr A* obtained with the EHT on a total of 13 observing nights over four years. Closure phases, which are the sum of visibility phases along a closed triangle of interferometer baselines, are used because they are robust against phase corruptions introduced by instrumentation and the rapidly variable atmosphere. The median closure phase on a triangle including telescopes in California, Hawaii, and Arizona is nonzero. This result conclusively demonstrates that the millimeter emission is asymmetric on scales of a few Schwarzschild radii and can be used to break 180° rotational ambiguities inherent from amplitude data alone. The stability of the sign of the closure phase over most observing nights indicates persistent asymmetry in the image of Sgr A* that is not obscured by refraction due to interstellar electrons along the line of sight

  6. PERSISTENT ASYMMETRIC STRUCTURE OF SAGITTARIUS A* ON EVENT HORIZON SCALES

    Energy Technology Data Exchange (ETDEWEB)

    Fish, Vincent L.; Doeleman, Sheperd S.; Lu, Ru-Sen; Akiyama, Kazunori; Beaudoin, Christopher; Cappallo, Roger [Massachusetts Institute of Technology, Haystack Observatory, Route 40, Westford, MA 01886 (United States); Johnson, Michael D.; Blackburn, Lindy; Blundell, Ray; Chael, Andrew A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Broderick, Avery E. [Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, ON N2L 2Y5 (Canada); Psaltis, Dimitrios; Chan, Chi-Kwan [Steward Observatory and Department of Astronomy, University of Arizona, 933 North Cherry Ave., Tucson, AZ 85721-0065 (United States); Alef, Walter; Bertarini, Alessandra [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany); Algaba, Juan Carlos [Korea Astronomy and Space Science Institute, 776 Daedeokdae-ro, Yuseong-gu, Daejeon 305-348 (Korea, Republic of); Asada, Keiichi [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); Bower, Geoffrey C. [Academia Sinica Institute for Astronomy and Astrophysics, 645 N. A‘ohōkū Place, Hilo, HI 96720 (United States); Brinkerink, Christiaan [Department of Astrophysics/IMAPP, Radboud University Nijmegen, P.O. Box 9010, 6500 GL, Nijmegen (Netherlands); Chamberlin, Richard, E-mail: vfish@haystack.mit.edu [Caltech Submillimeter Observatory, 111 Nowelo Street, Hilo, HI 96720 (United States); and others

    2016-04-01

    The Galactic Center black hole Sagittarius A* (Sgr A*) is a prime observing target for the Event Horizon Telescope (EHT), which can resolve the 1.3 mm emission from this source on angular scales comparable to that of the general relativistic shadow. Previous EHT observations have used visibility amplitudes to infer the morphology of the millimeter-wavelength emission. Potentially much richer source information is contained in the phases. We report on 1.3 mm phase information on Sgr A* obtained with the EHT on a total of 13 observing nights over four years. Closure phases, which are the sum of visibility phases along a closed triangle of interferometer baselines, are used because they are robust against phase corruptions introduced by instrumentation and the rapidly variable atmosphere. The median closure phase on a triangle including telescopes in California, Hawaii, and Arizona is nonzero. This result conclusively demonstrates that the millimeter emission is asymmetric on scales of a few Schwarzschild radii and can be used to break 180° rotational ambiguities inherent from amplitude data alone. The stability of the sign of the closure phase over most observing nights indicates persistent asymmetry in the image of Sgr A* that is not obscured by refraction due to interstellar electrons along the line of sight.

  7. NuSTAR detection of high-energy X-ray emission and rapid variability from Sagittarius A{sup *} flares

    Energy Technology Data Exchange (ETDEWEB)

    Barrière, Nicolas M.; Tomsick, John A.; Boggs, Steven E.; Craig, William W.; Zoglauer, Andreas [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Baganoff, Frederick K. [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139-4307 (United States); Christensen, Finn E. [DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Kgs. Lyngby (Denmark); Dexter, Jason [Departments of Physics and Astronomy, University of California, Berkeley, CA 94720 (United States); Grefenstette, Brian; Harrison, Fiona A.; Madsen, Kristin K. [Cahill Center for Astronomy and Astrophysics, Caltech, Pasadena, CA 91125 (United States); Hailey, Charles J.; Mori, Kaya; Zhang, Shuo [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Zhang, William W. [X-ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2014-05-01

    Sagittarius A{sup *} harbors the supermassive black hole that lies at the dynamical center of our Galaxy. Sagittarius A{sup *} spends most of its time in a low luminosity emission state but flares frequently in the infrared and X-ray, increasing up to a few hundred fold in brightness for up to a few hours at a time. The physical processes giving rise to the X-ray flares are uncertain. Here we report the detection with the NuSTAR observatory in Summer and Fall 2012 of four low to medium amplitude X-ray flares to energies up to 79 keV. For the first time, we clearly see that the power-law spectrum of Sagittarius A{sup *} X-ray flares extends to high energy, with no evidence for a cutoff. Although the photon index of the absorbed power-law fits are in agreement with past observations, we find a difference between the photon index of two of the flares (significant at the 95% confidence level). The spectra of the two brightest flares (∼55 times quiescence in the 2-10 keV band) are compared to simple physical models in an attempt to identify the main X-ray emission mechanism, but the data do not allow us to significantly discriminate between them. However, we confirm the previous finding that the parameters obtained with synchrotron models are, for the X-ray emission, physically more reasonable than those obtained with inverse Compton models. One flare exhibits large and rapid (<100 s) variability, which, considering the total energy radiated, constrains the location of the flaring region to be within ∼10 Schwarzschild radii of the black hole.

  8. DETECTING CHANGING POLARIZATION STRUCTURES IN SAGITTARIUS A* WITH HIGH FREQUENCY VLBI

    International Nuclear Information System (INIS)

    Fish, Vincent L.; Doeleman, Sheperd S.; Rogers, Alan E. E.; Broderick, Avery E.; Loeb, Abraham

    2009-01-01

    Sagittarius A* is the source of near infrared, X-ray, radio, and (sub)millimeter emission associated with the supermassive black hole at the Galactic Center. In the submillimeter regime, Sgr A* exhibits time-variable linear polarization on timescales corresponding to 6 M sun black hole. In previous work, we demonstrated the potential for total-intensity (sub)millimeter-wavelength very long baseline interferometry (VLBI) to detect time-variable-and periodic-source structure changes in the Sgr A* black hole system using nonimaging analyses. Here, we extend this work to include full polarimetric VLBI observations. We simulate full-polarization (sub)millimeter VLBI data of Sgr A* using a hot spot model that is embedded within an accretion disk, with emphasis on nonimaging polarimetric data products that are robust against calibration errors. Although the source-integrated linear polarization fraction in the models is typically only a few percent, the linear polarization fraction on small angular scales can be much higher, enabling the detection of changes in the polarimetric structure of Sgr A* on a wide variety of baselines. The shortest baselines track the source-integrated linear polarization fraction, while longer baselines are sensitive to polarization substructures that are beam-diluted by connected-element interferometry. The detection of periodic variability in source polarization should not be significantly affected even if instrumental polarization terms cannot be calibrated out. As more antennas are included in the (sub)millimeter-VLBI array, observations with full polarization will provide important new diagnostics to help disentangle intrinsic source polarization from Faraday rotation effects in the accretion and outflow region close to the black hole event horizon.

  9. DETECTING CHANGING POLARIZATION STRUCTURES IN SAGITTARIUS A* WITH HIGH FREQUENCY VLBI

    Energy Technology Data Exchange (ETDEWEB)

    Fish, Vincent L; Doeleman, Sheperd S; Rogers, Alan E. E. [Massachusetts Institute of Technology, Haystack Observatory, Route 40, Westford, MA 01886 (United States); Broderick, Avery E [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Loeb, Abraham [Institute for Theory and Computation, Harvard University, Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2009-12-01

    Sagittarius A* is the source of near infrared, X-ray, radio, and (sub)millimeter emission associated with the supermassive black hole at the Galactic Center. In the submillimeter regime, Sgr A* exhibits time-variable linear polarization on timescales corresponding to <10 Schwarzschild radii of the presumed 4 x 10{sup 6} M {sub sun} black hole. In previous work, we demonstrated the potential for total-intensity (sub)millimeter-wavelength very long baseline interferometry (VLBI) to detect time-variable-and periodic-source structure changes in the Sgr A* black hole system using nonimaging analyses. Here, we extend this work to include full polarimetric VLBI observations. We simulate full-polarization (sub)millimeter VLBI data of Sgr A* using a hot spot model that is embedded within an accretion disk, with emphasis on nonimaging polarimetric data products that are robust against calibration errors. Although the source-integrated linear polarization fraction in the models is typically only a few percent, the linear polarization fraction on small angular scales can be much higher, enabling the detection of changes in the polarimetric structure of Sgr A* on a wide variety of baselines. The shortest baselines track the source-integrated linear polarization fraction, while longer baselines are sensitive to polarization substructures that are beam-diluted by connected-element interferometry. The detection of periodic variability in source polarization should not be significantly affected even if instrumental polarization terms cannot be calibrated out. As more antennas are included in the (sub)millimeter-VLBI array, observations with full polarization will provide important new diagnostics to help disentangle intrinsic source polarization from Faraday rotation effects in the accretion and outflow region close to the black hole event horizon.

  10. Massive stars in the Sagittarius Dwarf Irregular Galaxy

    Science.gov (United States)

    Garcia, Miriam

    2018-02-01

    Low metallicity massive stars hold the key to interpret numerous processes in the past Universe including re-ionization, starburst galaxies, high-redshift supernovae, and γ-ray bursts. The Sagittarius Dwarf Irregular Galaxy [SagDIG, 12+log(O/H) = 7.37] represents an important landmark in the quest for analogues accessible with 10-m class telescopes. This Letter presents low-resolution spectroscopy executed with the Gran Telescopio Canarias that confirms that SagDIG hosts massive stars. The observations unveiled three OBA-type stars and one red supergiant candidate. Pending confirmation from high-resolution follow-up studies, these could be the most metal-poor massive stars of the Local Group.

  11. Chandra Discovers X-ray Source at the Center of Our Galaxy

    Science.gov (United States)

    2000-01-01

    Culminating 25 years of searching by astronomers, researchers at Massachusetts Institute of Technology say that a faint X-ray source, newly detected by NASA's Chandra X-ray Observatory, may be the long-sought X-ray emission from a known supermassive black hole at the center of our galaxy. Frederick K. Baganoff and colleagues from Pennsylvania State University, University Park, and the University of California, Los Angeles, will present their findings today in Atlanta at the 195th national meeting of the American Astronomical Society. Baganoff, lead scientist for the Chandra X-ray Observatory's Advanced CCD Imaging Spectrometer (ACIS) team's "Sagittarius A* and the Galactic Center" project and postdoctoral research associate at MIT, said that the precise positional coincidence between the new X-ray source and the radio position of a long-known source called Sagittarius A* "encourages us to believe that the two are the same." Sagittarius A* is a point-like, variable radio source at the center of our galaxy. It looks like a faint quasar and is believed to be powered by gaseous matter falling into a supermassive black hole with 2.6 million times the mass of our Sun. Chandra's remarkable detection of this X-ray source has placed astronomers within a couple of years of a coveted prize: measuring the spectrum of energy produced by Sagittarius A* to determine in detail how the supermassive black hole that powers it works. "The race to be the first to detect X-rays from Sagittarius A* is one of the hottest and longest-running in all of X-ray astronomy," Baganoff said. "Theorists are eager to hear the results of our observation so they can test their ideas." But now that an X-ray source close to Sagittarius A* has been found, it has taken researchers by surprise by being much fainter than expected. "There must be something unusual about the environment around this black hole that affects how it is fed and how the gravitational energy released from the infalling matter is

  12. Small-scale structure and chemical differentiation in the central region of the Sagittarius B2 molecular cloud

    International Nuclear Information System (INIS)

    Goldsmith, P.F.; Snell, R.L.; Hasegawa, T.; Ukita, N.; Nobeyama Radio Observatory, Minamimaki, Japan)

    1987-01-01

    Fifteen arcsec angular resolution observations of a number of molecular species in the center of the Sgr B2 molecular cloud, including HC3N in the ground and v7 = 1 vibrational states, SO, OCS,l and HNCO, have been performed. Emission from HC3N is fairly uniformly distributed over the region studied; SO and OCS have a spatially extended component but are strongly centrally peaked. HNCO and vibrationally excited HC 3 N emission are essentially restricted to a very small region around the center of activity in the north. The difference between the spatial distributions are attributed to variation in the chemical abundances of the various clumps. The excitation requirements of the vibrationally excited HC 3 N imply the presence of dust and gas at high temperatures. The results further heighten the apparent contradiction presented by the lack of infrared emission from this source. 53 references

  13. Detectability of weakly interacting massive particles in the Sagittarius dwarf tidal stream

    International Nuclear Information System (INIS)

    Freese, Katherine; Gondolo, Paolo; Newberg, Heidi Jo

    2005-01-01

    Tidal streams of the Sagittarius dwarf spheroidal galaxy (Sgr) may be showering dark matter onto the solar system and contributing ∼(0.3-23)% of the local density of our galactic halo. If the Sagittarius galaxy contains dark matter in the form of weakly interacting massive particles (WIMPs), the extra contribution from the stream gives rise to a steplike feature in the energy recoil spectrum in direct dark matter detection. For our best estimate of stream velocity (300 km/s) and direction (the plane containing the Sgr dwarf and its debris), the count rate is maximum on June 28 and minimum on December 27 (for most recoil energies), and the location of the step oscillates yearly with a phase opposite to that of the count rate. In the CDMS experiment, for 60 GeV WIMPs, the location of the step oscillates between 35 and 42 keV, and for the most favorable stream density, the stream should be detectable at the 11σ level in four years of data with 10 keV energy bins. Planned large detectors like XENON, CryoArray, and the directional detector DRIFT may also be able to identify the Sgr stream

  14. Sagittarius A* High-energy X-Ray Flare Properties during NuStar Monitoring of the Galactic Center from 2012 to 2015

    DEFF Research Database (Denmark)

    Zhang, Shuo; Baganoff, Frederick K.; Ponti, Gabriele

    2017-01-01

    Understanding the origin of the flaring activity from the Galactic center supermassive black hole Sagittarius A* is a major scientific goal of the NuSTAR Galactic plane survey campaign. We report on the data obtained between 2012 July and 2015 April, including 27 observations on Sgr A*, with a to......Understanding the origin of the flaring activity from the Galactic center supermassive black hole Sagittarius A* is a major scientific goal of the NuSTAR Galactic plane survey campaign. We report on the data obtained between 2012 July and 2015 April, including 27 observations on Sgr A...

  15. STRUCTURAL VARIATION OF MOLECULAR GAS IN THE SAGITTARIUS ARM AND INTERARM REGIONS

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, Tsuyoshi; Hasegawa, Tetsuo; Sugimoto, Masahiro [Joint ALMA Office, Alonso de Cordova 3107, Vitacura, Santiago 763-0355 (Chile); Koda, Jin [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800 (United States); Handa, Toshihiro, E-mail: sawada.tsuyoshi@nao.ac.jp [Department of Physics, Faculty of Science, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065 (Japan)

    2012-06-20

    We have carried out survey observations toward the Galactic plane at l Almost-Equal-To 38 Degree-Sign in the {sup 12}CO and {sup 13}CO J = 1-0 lines using the Nobeyama Radio Observatory 45 m telescope. A wide area (0.{sup 0}8 Multiplication-Sign 0.{sup 0}8) was mapped with high spatial resolution (17''). The line of sight samples the gas in both the Sagittarius arm and the interarm regions. The present observations reveal how the structure and physical conditions vary across a spiral arm. We classify the molecular gas in the line of sight into two distinct components based on its appearance: the bright and compact B component and the fainter and diffuse (i.e., more extended) D component. The B component is predominantly seen at the spiral arm velocities, while the D component dominates at the interarm velocities and is also found at the spiral arm velocities. We introduce the brightness distribution function and the brightness distribution index (BDI, which indicates the dominance of the B component) in order to quantify the map's appearance. The radial velocities of BDI peaks coincide with those of high {sup 12}CO J = 3-2/{sup 12}CO J = 1-0 intensity ratio (i.e., warm gas) and H II regions, and tend to be offset from the line brightness peaks at lower velocities (i.e., presumably downstream side of the arm). Our observations reveal that the gas structure at small scales changes across a spiral arm: bright and spatially confined structures develop in a spiral arm, leading to star formation at the downstream side, while extended emission dominates in the interarm region.

  16. THE EFFECTS OF ACCRETION FLOW DYNAMICS ON THE BLACK HOLE SHADOW OF SAGITTARIUS A*

    Energy Technology Data Exchange (ETDEWEB)

    Pu, Hung-Yi; Asada, Keiichi [Institute of Astronomy and Astrophysics, Academia Sinica, 11F of Astronomy-Mathematics Building, AS/NTU No. 1, Taipei 10617, Taiwan (China); Akiyama, Kazunori [Massachusetts Institute of Technology, Haystack Observatory, Route 40, Westford, MA 01886 (United States)

    2016-11-01

    A radiatively inefficient accretion flow (RIAF), which is commonly characterized by its sub-Keplerian nature, is a favored accretion model for the supermassive black hole at the Galactic center, Sagittarius A*. To investigate the observable features of an RIAF, we compare the modeled shadow images, visibilities, and spectra of three flow models with dynamics characterized by (i) a Keplerian shell that is rigidly rotating outside the innermost stable circular orbit (ISCO) and infalling with a constant angular momentum inside ISCO, (ii) a sub-Keplerian motion, and (iii) a free-falling motion with zero angular momentum at infinity. At near-millimeter wavelengths, the emission is dominated by the flow within several Schwarzschild radii. The energy shift due to these flow dynamics becomes important and distinguishable, suggesting that the flow dynamics are an important model parameter for interpreting the millimeter/sub-millimeter very long baseline interferometric observations with the forthcoming, fully assembled Event Horizon Telescope (EHT). As an example, we demonstrate that structural variations of Sagittarius A* on event horizon-scales detected in previous EHT observations can be explained by the non-stationary dynamics of an RIAF.

  17. THE EVENT HORIZON OF SAGITTARIUS A*

    International Nuclear Information System (INIS)

    Broderick, Avery E.; Loeb, Abraham; Narayan, Ramesh

    2009-01-01

    Black hole event horizons, causally separating the external universe from compact regions of spacetime, are one of the most exotic predictions of general relativity. Until recently, their compact size has prevented efforts to study them directly. Here we show that recent millimeter and infrared observations of Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, all but require the existence of a horizon. Specifically, we show that these observations limit the luminosity of any putative visible compact emitting region to below 0.4% of Sgr A*'s accretion luminosity. Equivalently, this requires the efficiency of converting the gravitational binding energy liberated during accretion into radiation and kinetic outflows to be greater than 99.6%, considerably larger than those implicated in Sgr A*, and therefore inconsistent with the existence of such a visible region. Finally, since we are able to frame this argument entirely in terms of observable quantities, our results apply to all geometric theories of gravity that admit stationary solutions, including the commonly discussed f(R) class of theories.

  18. THE EVENT HORIZON OF SAGITTARIUS A*

    Energy Technology Data Exchange (ETDEWEB)

    Broderick, Avery E [Canadian Institute for Theoretical Astrophysics, 60 St. George St., Toronto, ON M5S 3H8 (Canada); Loeb, Abraham; Narayan, Ramesh [Institute for Theory and Computation, Harvard University, Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

    2009-08-20

    Black hole event horizons, causally separating the external universe from compact regions of spacetime, are one of the most exotic predictions of general relativity. Until recently, their compact size has prevented efforts to study them directly. Here we show that recent millimeter and infrared observations of Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, all but require the existence of a horizon. Specifically, we show that these observations limit the luminosity of any putative visible compact emitting region to below 0.4% of Sgr A*'s accretion luminosity. Equivalently, this requires the efficiency of converting the gravitational binding energy liberated during accretion into radiation and kinetic outflows to be greater than 99.6%, considerably larger than those implicated in Sgr A*, and therefore inconsistent with the existence of such a visible region. Finally, since we are able to frame this argument entirely in terms of observable quantities, our results apply to all geometric theories of gravity that admit stationary solutions, including the commonly discussed f(R) class of theories.

  19. Field #3 of the Palomar-Groningen Survey; 1, Variable stars at the edge of the Sagittarius dwarf galaxy

    NARCIS (Netherlands)

    Schultheis, M.

    1996-01-01

    Submitted to: Astron. Astrophys. Abstract: A catalogue is presented with variable (RR Lyrae, semiregular and Mira) stars located inside field #3 of the Palomar-Groningen Survey, at the outer edge of the Sagittarius dwarf galaxy. One of the semiregular variables is a carbon star, comparable with

  20. A safe and cost-effective PMMA carbon source for MgB{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Ranot, Mahipal; Shinde, K. P.; Oh, Y. S.; Kang, S. H.; Chung, K. C. [Korea Institute of Materials Science, Changwon (Korea, Republic of); Jang, S. H. [Kiswire Advanced Technology Ltd, Daejeon (Korea, Republic of); Sinha, B. B. [National Centre for Nanoscience and Nanotechnology, University of Mumbai, Mumbai (India); Bhardwaj, A. [Dept. of Physics, Sungkyunkwan University, Suwon (Korea, Republic of)

    2017-03-15

    Carbon is proven to be very effective in pinning the magnetic vortices and improving the superconducting performance of MgB2 at high fields. In this work, we have used polymethyl methacrylate (PMMA) polymer as a safe and cost effective carbon source. The effects of molecular weight of PMMA on crystal structure, microstructure as well as on superconducting properties of MgB2 were studied. X-ray diffraction analysis revealed that there is a noticeable shift in (100) and (110) Bragg reflections towards higher angles, while no shift was observed in (002) reflections for MgB2 doped with different molecular weights of PMMA. This indicates that carbon could be substituted in the boron honeycomb layers without affecting the interlayer interactions. As compared to undoped MgB2, substantial enhancement in Jc(H) properties was obtained for PMMA-doped MgB2 samples both at 5 K and 20 K. The enhancement could be attributed to the effective carbon substitution for boron and the refinement of crystallite size by PMMA doping.

  1. Ages and Heavy Element Abundances from Very Metal-poor Stars in the Sagittarius Dwarf Galaxy

    Science.gov (United States)

    Hansen, Camilla Juul; El-Souri, Mariam; Monaco, Lorenzo; Villanova, Sandro; Bonifacio, Piercarlo; Caffau, Elisabetta; Sbordone, Luca

    2018-03-01

    Sagittarius (Sgr) is a massive disrupted dwarf spheroidal galaxy in the Milky Way halo that has undergone several stripping events. Previous chemical studies were restricted mainly to a few, metal-rich ([Fe/H] \\gtrapprox -1) stars that suggested a top-light initial mass function (IMF). Here we present the first high-resolution, very metal-poor ([Fe/H] =‑1 to ‑3) sample of 13 giant stars in the main body of Sgr. We derive abundances of 13 elements, namely C, Ca, Co, Fe, Sr, Ba, La, Ce, Nd, Eu, Dy, Pb, and Th, that challenge the interpretation based on previous studies. Our abundances from Sgr mimic those of the metal-poor halo, and our most metal-poor star ([Fe/H] ∼ -3) indicates a pure r-process pollution. Abundances of Sr, Pb, and Th are presented for the first time in Sgr, allowing for age determination using nuclear cosmochronology. We calculate ages of 9+/- 2.5 {Gyr}. Most of the sample stars have been enriched by a range of asymptotic giant branch (AGB) stars with masses between 1.3 and 5 M ⊙. Sgr J190651.47–320147.23 shows a large overabundance of Pb (2.05 dex) and a peculiar abundance pattern best fit by a 3 M ⊙ AGB star. Based on star-to-star scatter and observed abundance patterns, a mixture of low- and high-mass AGB stars and supernovae (15–25 M ⊙) is necessary to explain these patterns. The high level (0.29 ± 0.05 dex) of Ca indicates that massive supernovae must have existed and polluted the early ISM of Sgr before it lost its gas. This result is in contrast with a top-light IMF with no massive stars polluting Sgr. Based on data obtained UVES/VLT ID: 083.B-0774, 075.B-0127.

  2. Interstellar organic chemistry.

    Science.gov (United States)

    Sagan, C.

    1972-01-01

    Most of the interstellar organic molecules have been found in the large radio source Sagittarius B2 toward the galactic center, and in such regions as W51 and the IR source in the Orion nebula. Questions of the reliability of molecular identifications are discussed together with aspects of organic synthesis in condensing clouds, degradational origin, synthesis on grains, UV natural selection, interstellar biology, and contributions to planetary biology.

  3. A Pan-STARRS1 VIEW OF THE BIFURCATED SAGITTARIUS STREAM

    International Nuclear Information System (INIS)

    Slater, C. T.; Bell, E. F.; Schlafly, E. F.; Jurić, M.; Finkbeiner, D. P.; Martin, N. F.; Rix, H.-W.; Goldman, B.; Morganson, E. P.; Bernard, E. J.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Magnier, E. A.; Tonry, J. L.; Price, P. A.

    2013-01-01

    We use data from the Pan-STARRS1 survey to present a panoramic view of the Sagittarius tidal stream in the southern Galactic hemisphere. As a result of the extensive sky coverage of Pan-STARRS1, the southern stream is visible along more than 60° of its orbit, nearly double the length seen by the Sloan Digital Sky Survey. The recently discovered southern bifurcation of the stream is also apparent, with the fainter branch of the stream visible over at least 30°. Using a combination of fitting both the main-sequence turnoff and the red clump, we measure the distance to both arms of the stream in the south. We find that the distances to the bright arm of the stream agree very well with the N-body models of Law and Majewski. We also find that the faint arm lies ∼5 kpc closer to the Sun than the bright arm, similar to the behavior seen in the northern hemisphere.

  4. B2B Models for DoD Acquisition

    Science.gov (United States)

    2007-07-30

    product design, demand forecasting, asset management, and sales and marketing plans 35 Proctor & Gamble’s Private Industrial Network SOURCE: Laudon... B2B Models for DoD Acquisition 30 July 2007 by Magdi N. Kamel, Associate Professor Graduate School of Operational & Information Sciences...number. 1. REPORT DATE 30 JUL 2007 2. REPORT TYPE 3. DATES COVERED 00-00-2007 to 00-00-2007 4. TITLE AND SUBTITLE B2B Models for DoD

  5. Recreating the chemical evolution of the Sagittarius dwarf spheroidal from its tidal debris

    Science.gov (United States)

    Carlin, Jeffrey L.; Sheffield, Allyson; Cunha, Katia M. L.; Smith, Verne V.

    2018-06-01

    We present a detailed chemical analysis of the Sagittarius (Sgr) tidal stream based on high-resolution Gemini+GRACES spectra of 42 members of the highest surface brightness portions of both the trailing and leading arms of the Sgr stream. We select Sgr tidal stream candidates using a 2MASS+WISE color-color selection, combined with LAMOST radial velocities, allowing us to efficiently select Sgr stream members with little contamination from field stars. Sgr is a recently infallen, currently disrupting dwarf spheroidal galaxy, with roughly 70% of the luminosity of the Sgr system residing in the tidal streams. With this study, we provide a link between the (known) chemical properties in the intact Sgr core and the significant portion of the Sgr system's luminosity that is estimated to currently reside in the streams. In this talk, we focus on abundances of alpha-elements, but we will also analyze neutron-capture (both r- and s-process) and iron-peak species. We compare our chemical abundances to the few existing measurements in the stream as well as the numerous results in the Sgr core.

  6. An innovative technique to synthesize C-doped MgB2 by using chitosan as the carbon source

    International Nuclear Information System (INIS)

    Bovone, G; Kawale, S; Siri, A S; Vignolo, M; Bernini, C

    2014-01-01

    Here, we report a new technique to synthesize carbon-doped MgB 2 powder. Chitosan was innovatively used as the carbon source during the synthesis of boron from boron oxide. This allowed the introduction of local defects, which later on served as pinning centers in MgB 2 , in the boron lattice itself, avoiding the traditional and time consuming ways of ex situ MgB 2 doping (e.g. ball milling). Two volume percentages of C-doping have been tried and its effect on the superconducting properties, evaluated by magnetic and transport measurements, are discussed here. Morphological analysis by scanning electron microscopy revealed nano-metric grains’ distribution in the boron and MgB 2 powder. Mono-filamentary MgB 2 wires have been fabricated by an ex situ powder-in-tube technique by using the thus prepared carbon-doped MgB 2 and pure MgB 2 powders. Transport property measurements on these wires were made and compared with MgB 2 wire produced using commercial boron. (fast track communication)

  7. The Ital-FLAMES survey of the Sagittarius dwarf Spheroidal galaxy. I. Chemical abundances of bright RGB stars

    OpenAIRE

    Monaco, L.; Bellazzini, M.; Bonifacio, P.; Ferraro, F. R.; Marconi, G.; Pancino, E.; Sbordone, L.; Zaggia, S.

    2005-01-01

    We present iron and $\\alpha$ element (Mg, Ca, Ti) abundances for a sample of 15 Red Giant Branch stars belonging to the main body of the Sagittarius dwarf Spheroidal galaxy. Abundances have been obtained from spectra collected using the high resolution spectrograph FLAMES-UVES mounted at the VLT. Stars of our sample have a mean metallicity of [Fe/H]=-0.41$\\pm$0.20 with a metal poor tail extending to [Fe/H]=-1.52. The $\\alpha$ element abundance ratios are slightly subsolar for metallicities hi...

  8. Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)

    Science.gov (United States)

    Belloche, A.; Müller, H. S. P.; Menten, K. M.; Schilke, P.; Comito, C.

    2013-11-01

    Context. The discovery of amino acids in meteorites fallen to Earth and the detection of glycine, the simplest of them, in samples returned from a comet to Earth strongly suggest that the chemistry of the interstellar medium is capable of producing such complex organic molecules and that they may be widespread in our Galaxy. Aims: Our goal is to investigate the degree of chemical complexity that can be reached in the interstellar medium, in particular in dense star-forming regions. Methods: We performed an unbiased, spectral line survey toward Sgr B2(N) and (M), two regions where high-mass stars are formed, with the IRAM 30 m telescope in the 3 mm atmospheric transmission window. Partial surveys at 2 and 1.3 mm were performed in parallel. The spectra were analyzed with a simple radiative transfer model that assumes local thermodynamic equilibrium but takes optical depth effects into account. Results: About 3675 and 945 spectral lines with a peak signal-to-noise ratio higher than 4 are detected at 3 mm toward Sgr B2(N) and (M), i.e. about 102 and 26 lines per GHz, respectively. This represents an increase by about a factor of two over previous surveys of Sgr B2. About 70% and 47% of the lines detected toward Sgr B2(N) and (M) are identified and assigned to 56 and 46 distinct molecules as well as to 66 and 54 less abundant isotopologues of these molecules, respectively. In addition, we report the detection of transitions from 59 and 24 catalog entries corresponding to vibrationally or torsionally excited states of some of these molecules, respectively, up to a vibration energy of 1400 cm-1 (2000 K). Excitation temperatures and column densities were derived for each species but should be used with caution. The rotation temperatures of the detected complex molecules typically range from ~50 to 200 K. Among the detected molecules, aminoacetonitrile, n-propyl cyanide, and ethyl formate were reported for the first time in space based on this survey, as were five rare

  9. Sagittarius A* as an origin of the Galactic PeV cosmic rays?

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Yutaka [Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Murase, Kohta; Kimura, Shigeo S., E-mail: fujita@vega.ess.sci.osaka-u.ac.jp, E-mail: murase@psu.edu, E-mail: szk323@psu.edu [Center for Particle and Gravitational Astrophysics, Department of Physics, Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2017-04-01

    Supernova remnants (SNRs) have commonly been considered as a source of the observed PeV cosmic rays (CRs) or a Galactic PeV particle accelerator ('Pevatron'). In this work, we study Sagittarius A* (Sgr A*), which is the low-luminosity active galactic nucleus of the Milky Way Galaxy, as another possible canditate of the Pevatron, because it sometimes became very active in the past. We assume that a large number of PeV CRs were injected by Sgr A* at the outburst about 10{sup 7} yr ago when the Fermi bubbles were created. We constrain the diffusion coefficient for the CRs in the Galactic halo on the condition that the CRs have arrived on the Earth by now, while a fairly large fraction of them have escaped from the halo. Based on a diffusion-halo model, we solve a diffusion equation for the CRs and compare the results with the CR spectrum on the Earth. The observed small anisotropy of the arrival directions of CRs may be explained if the diffusion coefficient in the Galactic disk is smaller than that in the halo. Our model predicts that a boron-to-carbon ratio should be energy-independent around the knee, where the CRs from Sgr A* become dominant. It is unlikely that the spectrum of the CRs accelerated at the outburst is represented by a power-law similar to the one for those responsible for the gamma-ray emission from the central molecular zone (CMZ) around the Galactic center.

  10. Milky Way structure in the space between the Local and Sagittarius branches

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, V I; Guseva, N G [Kievskij Gosudarstvennyj Univ. (Ukrainian SSR). Astronomicheskaya Observatoriya; Metreveli, M D [AN Gruzinskoj SSR, Abastumi. Abastumanskaya Astrofizicheskaya Observatoriya

    1980-01-01

    The two areas of the Milky Way with their centres coincident with the open stellar clusters NGC 6823 and NGC 6802 (l=53 deg-63 deg) are studied. NGC 6823 direction passes tangentially along the inner side of the local spiral arm and that of NGC 6802 is located in the area between the local and Sagittarius spiral arms. In each area of 5 deg in diameter the density distribution of different spectral type stars and the dark matter is investigated. The results obtained are compared with the same data for the areas in the spiral arms (l=66 deg, 77 deg, 112 deg, 187 deg). The conclusion is drawn that the area between the spiral arms is characterised by a low density for all spectral type stars and neutal hydrogen and by a high one for the interstellar absorptive matter.

  11. Resolved magnetic-field structure and variability near the event horizon of Sagittarius A.

    Science.gov (United States)

    Johnson, Michael D; Fish, Vincent L; Doeleman, Sheperd S; Marrone, Daniel P; Plambeck, Richard L; Wardle, John F C; Akiyama, Kazunori; Asada, Keiichi; Beaudoin, Christopher; Blackburn, Lindy; Blundell, Ray; Bower, Geoffrey C; Brinkerink, Christiaan; Broderick, Avery E; Cappallo, Roger; Chael, Andrew A; Crew, Geoffrey B; Dexter, Jason; Dexter, Matt; Freund, Robert; Friberg, Per; Gold, Roman; Gurwell, Mark A; Ho, Paul T P; Honma, Mareki; Inoue, Makoto; Kosowsky, Michael; Krichbaum, Thomas P; Lamb, James; Loeb, Abraham; Lu, Ru-Sen; MacMahon, David; McKinney, Jonathan C; Moran, James M; Narayan, Ramesh; Primiani, Rurik A; Psaltis, Dimitrios; Rogers, Alan E E; Rosenfeld, Katherine; SooHoo, Jason; Tilanus, Remo P J; Titus, Michael; Vertatschitsch, Laura; Weintroub, Jonathan; Wright, Melvyn; Young, Ken H; Zensus, J Anton; Ziurys, Lucy M

    2015-12-04

    Near a black hole, differential rotation of a magnetized accretion disk is thought to produce an instability that amplifies weak magnetic fields, driving accretion and outflow. These magnetic fields would naturally give rise to the observed synchrotron emission in galaxy cores and to the formation of relativistic jets, but no observations to date have been able to resolve the expected horizon-scale magnetic-field structure. We report interferometric observations at 1.3-millimeter wavelength that spatially resolve the linearly polarized emission from the Galactic Center supermassive black hole, Sagittarius A*. We have found evidence for partially ordered magnetic fields near the event horizon, on scales of ~6 Schwarzschild radii, and we have detected and localized the intrahour variability associated with these fields. Copyright © 2015, American Association for the Advancement of Science.

  12. TRACING SAGITTARIUS STRUCTURE WITH SDSS AND SEGUE IMAGING AND SPECTROSCOPY

    International Nuclear Information System (INIS)

    Yanny, Brian; Newberg, Heidi Jo; Johnson, Jennifer A.; Lee, Young Sun; Beers, Timothy C.; Bizyaev, Dmitry; Brewington, Howard; Malanushenko, Elena; Malanushenko, Viktor; Oravetz, Dan; Pan, Kaike; Simmons, Audrey; Snedden, Stephanie; Fiorentin, Paola Re; Harding, Paul

    2009-01-01

    We show that the Sagittarius dwarf tidal stream can be traced with very red K/M-giant stars, selected from Sloan Digital Sky Survey (SDSS) photometry. A subset of these stars are spectroscopically confirmed with SEGUE and SDSS spectra, and the distance scale of 2MASS and SDSS M giants is calibrated to the RR Lyrae distance scale. The absolute magnitude of the K/M-giant stars at the tip of the giant branch is M g 0 =-1.0. The line-of-sight velocities of the M giant and blue horizontal-branch (BHB) stars that are spatially coincident with the Sgr dwarf tidal stream are consistent with those of previous authors, reinforcing the need for new models that can explain all of the Sgr tidal debris stream observations. We estimate stellar densities along the tidal tails that can be used to help constrain future models. The K/M giant, BHB, and F-turnoff stars in the lower surface brightness tidal stream that is adjacent to the main leading Sgr dwarf tidal tail have velocities and metallicities that are similar to those of the stars in the leading tidal tail. The ratio of K/M giants to BHBs and BHBs to F-turnoff stars are also similar for both branches of the leading tidal tail. We show that there is an additional low-metallicity tidal stream near the Sgr trailing tidal tail.

  13. The impact of Faraday effects on polarized black hole images of Sagittarius A*.

    Science.gov (United States)

    Jiménez-Rosales, Alejandra; Dexter, Jason

    2018-05-01

    We study model images and polarization maps of Sagittarius A* at 230 GHz. We post-process GRMHD simulations and perform a fully relativistic radiative transfer calculation of the emitted synchrotron radiation to obtain polarized images for a range of mass accretion rates and electron temperatures. At low accretion rates, the polarization map traces the underlying toroidal magnetic field geometry. At high accretion rates, we find that Faraday rotation internal to the emission region can depolarize and scramble the map. We measure the net linear polarization fraction and find that high accretion rate "jet-disc" models are heavily depolarized and are therefore disfavoured. We show how Event Horizon Telescope measurements of the polarized "correlation length" over the image provide a model-independent upper limit on the strength of these Faraday effects, and constrain plasma properties like the electron temperature and magnetic field strength.

  14. 1.3 mm WAVELENGTH VLBI OF SAGITTARIUS A*: DETECTION OF TIME-VARIABLE EMISSION ON EVENT HORIZON SCALES

    International Nuclear Information System (INIS)

    Fish, Vincent L.; Doeleman, Sheperd S.; Beaudoin, Christopher; Bolin, David E.; Rogers, Alan E. E.; Blundell, Ray; Gurwell, Mark A.; Moran, James M.; Primiani, Rurik; Bower, Geoffrey C.; Plambeck, Richard; Chamberlin, Richard; Freund, Robert; Friberg, Per; Honma, Mareki; Oyama, Tomoaki; Inoue, Makoto; Krichbaum, Thomas P.; Lamb, James; Marrone, Daniel P.

    2011-01-01

    Sagittarius A*, the ∼4 x 10 6 M sun black hole candidate at the Galactic center, can be studied on Schwarzschild radius scales with (sub)millimeter wavelength very long baseline interferometry (VLBI). We report on 1.3 mm wavelength observations of Sgr A* using a VLBI array consisting of the JCMT on Mauna Kea, the Arizona Radio Observatory's Submillimeter Telescope on Mt. Graham in Arizona, and two telescopes of the CARMA array at Cedar Flat in California. Both Sgr A* and the quasar calibrator 1924-292 were observed over three consecutive nights, and both sources were clearly detected on all baselines. For the first time, we are able to extract 1.3 mm VLBI interferometer phase information on Sgr A* through measurement of closure phase on the triangle of baselines. On the third night of observing, the correlated flux density of Sgr A* on all VLBI baselines increased relative to the first two nights, providing strong evidence for time-variable change on scales of a few Schwarzschild radii. These results suggest that future VLBI observations with greater sensitivity and additional baselines will play a valuable role in determining the structure of emission near the event horizon of Sgr A*.

  15. A systematic analysis of the Braitenberg vehicle 2b for point-like stimulus sources

    International Nuclear Information System (INIS)

    Rañó, Iñaki

    2012-01-01

    Braitenberg vehicles have been used experimentally for decades in robotics with limited empirical understanding. This paper presents the first mathematical model of the vehicle 2b, displaying so-called aggression behaviour, and analyses the possible trajectories for point-like smooth stimulus sources. This sensory-motor steering control mechanism is used to implement biologically grounded target approach, target-seeking or obstacle-avoidance behaviour. However, the analysis of the resulting model reveals that complex and unexpected trajectories can result even for point-like stimuli. We also prove how the implementation of the controller and the vehicle morphology interact to affect the behaviour of the vehicle. This work provides a better understanding of Braitenberg vehicle 2b, explains experimental results and paves the way for a formally grounded application on robotics as well as for a new way of understanding target seeking in biology. (paper)

  16. APOGEE Chemical Abundances of the Sagittarius Dwarf Galaxy

    International Nuclear Information System (INIS)

    Hasselquist, Sten; Holtzman, Jon; Shetrone, Matthew; Smith, Verne; Nidever, David L.; McWilliam, Andrew; Fernández-Trincado, J. G.; Tang, Baitian; Beers, Timothy C.; Majewski, Steven R.; Anguiano, Borja; Tissera, Patricia B.; Alvar, Emma Fernández; Carigi, Leticia; Delgado Inglada, Gloria; Allende Prieto, Carlos; Battaglia, Giuseppina; García-Hernández, D. A.; Almeida, Andres; Frinchaboy, Peter

    2017-01-01

    The Apache Point Observatory Galactic Evolution Experiment provides the opportunity of measuring elemental abundances for C, N, O, Na, Mg, Al, Si, P, K, Ca, V, Cr, Mn, Fe, Co, and Ni in vast numbers of stars. We analyze thechemical-abundance patterns of these elements for 158 red giant stars belonging to the Sagittarius dwarf galaxy (Sgr). This is the largest sample of Sgr stars with detailed chemical abundances, and it is the first time that C, N, P, K, V, Cr, Co, and Ni have been studied at high resolution in this galaxy. We find that the Sgr stars with [Fe/H] ≳ −0.8 are deficient in all elemental abundance ratios (expressed as [X/Fe]) relative to the Milky Way, suggesting that the Sgr stars observed today were formed from gas that was less enriched by Type II SNe than stars formed in the Milky Way. By examining the relative deficiencies of the hydrostatic (O, Na, Mg, and Al) and explosive (Si, P, K, and Mn) elements, our analysis supports the argument that previous generations of Sgr stars were formed with a top-light initial mass function, one lacking the most massive stars that would normally pollute the interstellar medium with the hydrostatic elements. We use a simple chemical-evolution model, flexCE, to further support our claim and conclude that recent stellar generations of Fornax and the Large Magellanic Cloud could also have formed according to a top-light initial mass function.

  17. APOGEE Chemical Abundances of the Sagittarius Dwarf Galaxy

    Energy Technology Data Exchange (ETDEWEB)

    Hasselquist, Sten; Holtzman, Jon [New Mexico State University, Las Cruces, NM 88003 (United States); Shetrone, Matthew [University of Texas at Austin, McDonald Observatory, Fort Davis, TX 79734 (United States); Smith, Verne; Nidever, David L. [National Optical Astronomy Observatories, Tucson, AZ 85719 (United States); McWilliam, Andrew [The Observatories of the Carnegie Institute of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Fernández-Trincado, J. G.; Tang, Baitian [Departamento de Astronomía, Casilla 160-C, Universidad de Concepción, Concepción (Chile); Beers, Timothy C. [Department of Physics and JINA Center for the Evolution of the Elements, University of Notre Dame, Notre Dame, IN 46556 (United States); Majewski, Steven R.; Anguiano, Borja [Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States); Tissera, Patricia B. [Department of Physics, Universidad Andres Bello, 700 Fernandez Concha (Chile); Alvar, Emma Fernández; Carigi, Leticia; Delgado Inglada, Gloria [Instituto de Astronomía, Universidad Nacional Autnoma de México, Apdo. Postal 70264, Ciudad de México, 04510 (Mexico); Allende Prieto, Carlos; Battaglia, Giuseppina; García-Hernández, D. A. [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Almeida, Andres [Departamento de Física, Facultad de Ciencias, Universidad de La Serena, Cisternas 1200, La Serena (Chile); Frinchaboy, Peter, E-mail: sten@nmsu.edu, E-mail: holtz@nmsu.edu, E-mail: shetrone@astro.as.utexas.edu, E-mail: vsmith@email.noao.edu [Texas Christian University, Fort Worth, TX 76129 (United States); and others

    2017-08-20

    The Apache Point Observatory Galactic Evolution Experiment provides the opportunity of measuring elemental abundances for C, N, O, Na, Mg, Al, Si, P, K, Ca, V, Cr, Mn, Fe, Co, and Ni in vast numbers of stars. We analyze thechemical-abundance patterns of these elements for 158 red giant stars belonging to the Sagittarius dwarf galaxy (Sgr). This is the largest sample of Sgr stars with detailed chemical abundances, and it is the first time that C, N, P, K, V, Cr, Co, and Ni have been studied at high resolution in this galaxy. We find that the Sgr stars with [Fe/H] ≳ −0.8 are deficient in all elemental abundance ratios (expressed as [X/Fe]) relative to the Milky Way, suggesting that the Sgr stars observed today were formed from gas that was less enriched by Type II SNe than stars formed in the Milky Way. By examining the relative deficiencies of the hydrostatic (O, Na, Mg, and Al) and explosive (Si, P, K, and Mn) elements, our analysis supports the argument that previous generations of Sgr stars were formed with a top-light initial mass function, one lacking the most massive stars that would normally pollute the interstellar medium with the hydrostatic elements. We use a simple chemical-evolution model, flexCE, to further support our claim and conclude that recent stellar generations of Fornax and the Large Magellanic Cloud could also have formed according to a top-light initial mass function.

  18. Recycling source terms for edge plasma fluid models and impact on convergence behaviour of the BRAAMS 'B2' code

    International Nuclear Information System (INIS)

    Maddison, G.P.; Reiter, D.

    1994-02-01

    Predictive simulations of tokamak edge plasmas require the most authentic description of neutral particle recycling sources, not merely the most expedient numerically. Employing a prototypical ITER divertor arrangement under conditions of high recycling, trial calculations with the 'B2' steady-state edge plasma transport code, plus varying approximations or recycling, reveal marked sensitivity of both results and its convergence behaviour to details of sources incorporated. Comprehensive EIRENE Monte Carlo resolution of recycling is implemented by full and so-called 'shot' intermediate cycles between the plasma fluid and statistical neutral particle models. As generally for coupled differencing and stochastic procedures, though, overall convergence properties become more difficult to assess. A pragmatic criterion for the 'B2'/EIRENE code system is proposed to determine its success, proceeding from a stricter condition previously identified for one particular analytic approximation of recycling in 'B2'. Certain procedures are also inferred potentially to improve their convergence further. (orig.)

  19. Identifying the sources driving observed PM2.5 temporal variability over Halifax, Nova Scotia, during BORTAS-B

    Directory of Open Access Journals (Sweden)

    M. D. Gibson

    2013-07-01

    Full Text Available The source attribution of observed variability of total PM2.5 concentrations over Halifax, Nova Scotia, was investigated between 11 July and 26 August 2011 using measurements of PM2.5 mass and PM2.5 chemical composition (black carbon, organic matter, anions, cations and 33 elements. This was part of the BORTAS-B (quantifying the impact of BOReal forest fires on Tropospheric oxidants using Aircraft and Satellites experiment, which investigated the atmospheric chemistry and transport of seasonal boreal wildfire emissions over eastern Canada in 2011. The US EPA Positive Matrix Factorization (PMF receptor model was used to determine the average mass (percentage source contribution over the 45 days, which was estimated to be as follows: long-range transport (LRT pollution: 1.75 μg m−3 (47%; LRT pollution marine mixture: 1.0 μg m−3 (27.9%; vehicles: 0.49 μg m−3 (13.2%; fugitive dust: 0.23 μg m−3 (6.3%; ship emissions: 0.13 μg m−3 (3.4%; and refinery: 0.081 μg m−3 (2.2%. The PMF model describes 87% of the observed variability in total PM2.5 mass (bias = 0.17 and RSME = 1.5 μg m−3. The factor identifications are based on chemical markers, and they are supported by air mass back trajectory analysis and local wind direction. Biomass burning plumes, found by other surface and aircraft measurements, were not significant enough to be identified in this analysis. This paper presents the results of the PMF receptor modelling, providing valuable insight into the local and upwind sources impacting surface PM2.5 in Halifax and a vital comparative data set for the other collocated ground-based observations of atmospheric composition made during BORTAS-B.

  20. Widespread rotationally hot hydronium ion in the galactic interstellar medium

    International Nuclear Information System (INIS)

    Lis, D. C.; Phillips, T. G.; Schilke, P.; Comito, C.; Higgins, R.

    2014-01-01

    We present new Herschel observations of the (6,6) and (9,9) inversion transitions of the hydronium ion toward Sagittarius B2(N) and W31C. Sensitive observations toward Sagittarius B2(N) show that the high, ∼500 K, rotational temperatures characterizing the population of the highly excited metastable H 3 O + rotational levels are present over a wide range of velocities corresponding to the Sagittarius B2 envelope, as well as the foreground gas clouds between the Sun and the source. Observations of the same lines toward W31C, a line of sight that does not intersect the Central Molecular Zone but instead traces quiescent gas in the Galactic disk, also imply a high rotational temperature of ∼380 K, well in excess of the kinetic temperature of the diffuse Galactic interstellar medium. While it is plausible that some fraction of the molecular gas may be heated to such high temperatures in the active environment of the Galactic center, characterized by high X-ray and cosmic-ray fluxes, shocks, and high degree of turbulence, this is unlikely in the largely quiescent environment of the Galactic disk clouds. We suggest instead that the highly excited states of the hydronium ion are populated mainly by exoergic chemical formation processes and the temperature describing the rotational level population does not represent the physical temperature of the medium. The same arguments may be applicable to other symmetric top rotors, such as ammonia. This offers a simple explanation of the long-standing puzzle of the presence of a pervasive, hot molecular gas component in the central region of the Milky Way. Moreover, our observations suggest that this is a universal process not limited to the active environments associated with galactic nuclei.

  1. Effect of cobalt sources on properties of co-b catalysts synthesized by sol-gel method

    Energy Technology Data Exchange (ETDEWEB)

    Figen, Aysel Kantürk; Co ú kuner, Bilge; Özdemir, Özgül Dere [Department of Chemical Engineering, Yildiz Technical University Istanbul (Turkey); Burçin Pi ú kin, Mehmet [Department of Bioengineering, Y Õ ld Õ z Technical University, Istanbul (Turkey)

    2013-07-01

    In this studying, Co-B catalysts were prepared by sol-gel method via kinds of cobalt source for clarifying the effect of these for characteristic properties of Co-B catalysts. Co sources, cobalt(II)chloride (CoCl{sub 2} .6H{sub 2}O), cobalt(II)sulfate (CoSO{sub 4} .7H{sub 2}O) and cobalt(II)nitrate (Co(NO{sub 3}){sub 2} .6H{sub 2}O), were used as a metal source with boron oxide (B{sub 2}O{sub 3} ) while citric acid (C{sub 6}H{sub 8}O{sub 7} ) used as organic ligand to forming sol-gel structure. The crystalline structures of Co-B catalysts were determined by X-ray diffraction. The N{sub 2} sorption technique was used for analyzing catalysts surface area. The variety of Co-B catalysts morphological properties were investigated via scanning electron microscope. By the effect of cobalt sources the Co-B catalyst’s properties were altered that clarified from analysis results. The amorphous Co-B catalyst produced from CoCl{sub 2}.6H{sub 2} O as metal source had the largest porous surface area with 122.7 m 2 .g -1 . Investigation of hydrolysis were performed under variety of temperatures (22, 40 and 60 o C), NaOH concentrations (1-15 wt. %) and NaBH 4 /Co-B catalyst ratio (2-40 wt./wt.) ratios in order to investigate the activation of Co-B catalyst. The maximum hydrogen generation rate 0.84L H 2 .min -1 .g -1 was obtained under 40 °C, 10 wt. % NaOH and 9.52wt./wt. NaBH{sub 4}/Co-B catalyst ratio. Yet the kinetic investigations, the reaction order was found that zero order with 0.9954 coefficient of correlation and 51.83 kJ/mol activation energy. Key words: Sol-gel, Co-B Catalyst, Boron.

  2. THE CHEMISTRY OF THE TRAILING ARM OF THE SAGITTARIUS DWARF GALAXY

    International Nuclear Information System (INIS)

    Keller, Stefan C.; Yong, David; Da Costa, Gary S.

    2010-01-01

    We present abundances of C, O, Ti, and Fe for 11 M-giant stars in the trailing tidal arm of the Sagittarius dwarf (Sgr). The abundances were derived by comparing synthetic spectra with high-resolution infrared spectra obtained with the Phoenix spectrograph on the Gemini South telescope. The targeted stars are drawn from two regions of the Sgr trailing arm separated by 66 0 (five stars) and 132 0 (six stars) from the main body of Sgr. The trailing arm provides a more direct diagnostic of the chemical evolution of Sgr compared to the extensively phase-mixed leading arm. Within our restricted sample of ∼2-3 Gyr old stars, we find that the stream material exhibits a significant metallicity gradient of -(2.4 ± 0.3) x 10 -3 dex/degree (-(9.4 ± 1.1) x 10 -4 dex/kpc) away from the main body of Sgr. The tidal disruption of Sgr is a relatively recent event. We therefore interpret the presence of a metallicity gradient in the debris as indicative of a similar gradient in the progenitor. The fact that such a metallicity gradient survived for almost a Hubble time indicates that the efficiency of radial mixing was very low in the Sgr progenitor. No significant gradient is seen to exist in the [α/Fe] abundance ratio along the trailing arm. Our results may be accounted for by a radial decrease in star formation efficiency and/or radial increase in the efficiency of galactic wind-driven metal loss in the chemical evolution of the Sgr progenitor. The [Ti/Fe] and [O/Fe] abundance ratios observed within the stream are distinct from those of the Galactic halo. We conclude that the fraction of the intermediate to metal-rich halo population contributed by the recent dissolution (<3 Gyr) of Sgr-like dwarf galaxies cannot be substantial.

  3. Soft X-ray sources and their optical counterparts in the error box of the COS-B source 2CG 135+01

    Energy Technology Data Exchange (ETDEWEB)

    Caraveo, P A; Bignami, G F [Consiglio Nazionale delle Ricerche, Milan (Italy). Lab. di Fisica Cosmica e Tecnologie Relative; Paul, J A [CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Section d' Astrophysique; Marano, B [Bologna Univ. (Italy). Ist. di Astronomia; Vettolani, G P [Consiglio Nazionale delle Ricerche, Bologna (Italy). Lab. di Radioastronomia

    1981-01-01

    We shall present here the Einstein observations for the 2CG 135+01 region where the results are complete in the sense that we have a satisfactory coverage of the COS-B error box and, more important, that all the IPC sources found have been identified, through both HRI and optical observations. In particular, the new spectral classifications of the present work were obtained at the Lojano Observatory (Bologna, Italy) with the Boller and Chivens spectrograph at the Cassegrain focus of the 1.52 in telescope. The spectral dispersion is 80 A/mm.

  4. Hydrodynamic Simulations of the Inner Accretion Flow of Sagittarius A* Fueled By Stellar Winds

    Science.gov (United States)

    Ressler, S. M.; Quataert, E.; Stone, J. M.

    2018-05-01

    We present Athena++ grid-based, hydrodynamic simulations of accretion onto Sagittarius A* via the stellar winds of the ˜30 Wolf-Rayet stars within the central parsec of the galactic center. These simulations span ˜ 4 orders of magnitude in radius, reaching all the way down to 300 gravitational radii of the black hole, ˜32 times further in than in previous work. We reproduce reasonably well the diffuse thermal X-ray emission observed by Chandra in the central parsec. The resulting accretion flow at small radii is a superposition of two components: 1) a moderately unbound, sub-Keplerian, thick, pressure-supported disc that is at most (but not all) times aligned with the clockwise stellar disc, and 2) a bound, low-angular momentum inflow that proceeds primarily along the southern pole of the disc. We interpret this structure as a natural consequence of a few of the innermost stellar winds dominating accretion, which produces a flow with a broad distribution of angular momentum. Including the star S2 in the simulation has a negligible effect on the flow structure. Extrapolating our results from simulations with different inner radii, we find an accretion rate of ˜ a few × 10-8M⊙/yr at the horizon scale, consistent with constraints based on modeling the observed emission of Sgr A*. The flow structure found here can be used as more realistic initial conditions for horizon scale simulations of Sgr A*.

  5. Automated Report Generation for Research Data Repositories: From i2b2 to PDF.

    Science.gov (United States)

    Thiemann, Volker S; Xu, Tingyan; Röhrig, Rainer; Majeed, Raphael W

    2017-01-01

    We developed an automated toolchain to generate reports of i2b2 data. It is based on free open source software and runs on a Java Application Server. It is sucessfully used in an ED registry project. The solution is highly configurable and portable to other projects based on i2b2 or compatible factual data sources.

  6. Vitamin B12-Containing Plant Food Sources for Vegetarians

    Science.gov (United States)

    Watanabe, Fumio; Yabuta, Yukinori; Bito, Tomohiro; Teng, Fei

    2014-01-01

    The usual dietary sources of Vitamin B12 are animal-derived foods, although a few plant-based foods contain substantial amounts of Vitamin B12. To prevent Vitamin B12 deficiency in high-risk populations such as vegetarians, it is necessary to identify plant-derived foods that contain high levels of Vitamin B12. A survey of naturally occurring plant-derived food sources with high Vitamin B12 contents suggested that dried purple laver (nori) is the most suitable Vitamin B12 source presently available for vegetarians. Furthermore, dried purple laver also contains high levels of other nutrients that are lacking in vegetarian diets, such as iron and n-3 polyunsaturated fatty acids. Dried purple laver is a natural plant product and it is suitable for most people in various vegetarian groups. PMID:24803097

  7. Vitamin B12-Containing Plant Food Sources for Vegetarians

    Directory of Open Access Journals (Sweden)

    Fumio Watanabe

    2014-05-01

    Full Text Available The usual dietary sources of Vitamin B12 are animal-derived foods, although a few plant-based foods contain substantial amounts of Vitamin B12. To prevent Vitamin B12 deficiency in high-risk populations such as vegetarians, it is necessary to identify plant-derived foods that contain high levels of Vitamin B12. A survey of naturally occurring plant-derived food sources with high Vitamin B12 contents suggested that dried purple laver (nori is the most suitable Vitamin B12 source presently available for vegetarians. Furthermore, dried purple laver also contains high levels of other nutrients that are lacking in vegetarian diets, such as iron and n-3 polyunsaturated fatty acids. Dried purple laver is a natural plant product and it is suitable for most people in various vegetarian groups.

  8. Chemical Abundances of Hydrostatic and Explosive Alpha-elements in Sagittarius Stream Stars

    Science.gov (United States)

    Carlin, Jeffrey L.; Sheffield, Allyson A.; Cunha, Katia; Smith, Verne V.

    2018-05-01

    We analyze chemical abundances of stars in the Sagittarius (Sgr) tidal stream using high-resolution Gemini+GRACES spectra of 42 members of the highest surface-brightness portions of both the trailing and leading arms. Targets were chosen using a 2MASS+WISE color–color selection, combined with the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) radial velocities. In this Letter, we analyze [Fe/H] and α-elements produced by both hydrostatic (O, Mg) and explosive (Si, Ca, Ti) nucleosynthetic processes. The average [Fe/H] for our Sgr stream stars is lower than that for stars in the Sgr core, and stars in the trailing and leading arms show systematic differences in [Fe/H]. Both hydrostatic and explosive elements are depleted relative to Milky Way (MW) disk and halo stars, with a larger gap between the MW trend and Sgr stars for the hydrostatic elements. Chemical abundances of Sgr stream stars show similar patterns to those measured in the core of the Sgr dSph. We explore the ratio of hydrostatic to explosive α-elements [α h/ex] (which we refer to as the “HEx ratio”). Our observed HEx ratio trends for Sgr debris are deficient relative to MW stars. Via simple chemical evolution modeling, we show that these HEx ratio patterns are consistent with a Sgr IMF that lacks the most massive stars. This study provides a link between the chemical properties in the intact Sgr core and the significant portion of the Sgr system’s luminosity that is estimated to currently reside in the streams.

  9. Approaching hell's kitchen: Molecular daredevil clouds in the vicinity of Sagittarius A* ⋆⋆

    Science.gov (United States)

    Moser, Lydia; Sánchez-Monge, Álvaro; Eckart, Andreas; Requena-Torres, Miguel A.; García-Marin, Macarena; Kunneriath, Devaky; Zensus, Anton; Britzen, Silke; Sabha, Nadeen; Shahzamanian, Banafsheh; Borkar, Abhijeet; Fischer, Sebastian

    2017-07-01

    We report serendipitous detections of line emission with the Atacama Large Millimeter/submillimeter Array (ALMA) in bands 3, 6, and 7 in the central parsec down to within 1'' around Sgr A* at an up to now highest resolution (electron temperature around Te 6000 K for the minispiral. The spectral index (S ∝ να) of Sagittarius A* (Sgr A*) is 0.5 at 100-250 GHz and 0.0 at 230-340 GHz. The bright sources in the center show spectral indices around -0.1 implying Bremsstrahlung emission, while dust emission is emerging in the minispiral exterior. Apart from CS, which is most widespread in the center, H13CO+, HC3N, SiO, SO, C2H, CH3OH, 13CS and N2H+ are also detected. The bulk of the clumpy emission regions is at positive velocities and in a region confined by the minispiral northern arm (NA), bar, and the sources IRS 3 and 7. Although partly spatially overlapping with the radio recombination line (RRL) emission at same negative velocities, the relation to the minispiral remains unclear. A likely explanation is an infalling clump consisting of denser cloud cores embedded in diffuse gas. This central association (CA) of clouds shows three times higher CS/X (X: any other observed molecule) ratios than the circumnuclear disk (CND) suggesting a combination of higher excitation, by a temperature gradient and/or infrared (IR) pumping, and abundance enhancement due to UV and/or X-ray emission. Hence, we conclude that this CA is closer to the center than the CND is to the center. Moreover, we find molecular line emission at velocities up to 200 km s-1. Apart from the CA, we identified two intriguing regions in the CND. One region shows emission in all molecular species and higher energy levels tested in this and previous observations and contains a methanol class I maser. The other region shows similar behavior of the line ratios such as the CA. Outside the CND, we find the traditionally quiescent gas tracer N2H+ coinciding with the largest IR dark clouds in the field. Methanol

  10. ESTIMATING THE PARAMETERS OF SAGITTARIUS A*'s ACCRETION FLOW VIA MILLIMETER VLBI

    Energy Technology Data Exchange (ETDEWEB)

    Broderick, Avery E [Canadian Institute for Theoretical Astrophysics, 60 St. George St., Toronto, ON M5S 3H8 (Canada); Fish, Vincent L; Doeleman, Sheperd S [Massachusetts Institute of Technology, Haystack Observatory, Route 40, Westford, MA 01886 (United States); Loeb, Abraham [Institute for Theory and Computation, Harvard University, Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

    2009-05-20

    Recent millimeter-VLBI observations of Sagittarius A* (Sgr A*) have, for the first time, directly probed distances comparable to the horizon scale of a black hole. This provides unprecedented access to the environment immediately around the horizon of an accreting black hole. We leverage both existing spectral and polarization measurements and our present understanding of accretion theory to produce a suite of generic radiatively inefficient accretion flow (RIAF) models of Sgr A*, which we then fit to these recent millimeter-VLBI observations. We find that if the accretion flow onto Sgr A* is well described by an RIAF model, the orientation and magnitude of the black hole's spin are constrained to a two-dimensional surface in the spin, inclination, position angle parameter space. For each of these, we find the likeliest values and their 1{sigma} and 2{sigma} errors to be a = 0{sup +0.4+0.7}, {theta}=50{sup o+10{sup o}}{sup +30{sup o}}{sub -10{sup o}}{sub -10{sup o}}, and {xi}=-20{sup o+31{sup o}}{sup +107{sup o}}{sub -16{sup o}}{sub -29{sup o}}, when the resulting probability distribution is marginalized over the others. The most probable combination is a = 0{sup +0.2+0.4}, {theta}=90{sup o}{sub -40{sup o}}{sub -50{sup o}}, and {xi}=-14{sup o+7{sup o}}{sup +11{sup o}}{sub -7{sup o}}{sub -11{sup o}}, though the uncertainties on these are very strongly correlated, and high probability configurations exist for a variety of inclination angles above 30 deg. and spins below 0.99. Nevertheless, this demonstrates the ability millimeter-VLBI observations, even with only a few stations, to significantly constrain the properties of Sgr A*.

  11. Sugar as an optimal carbon source for the enhanced performance of MgB2 superconductors at high magnetic fields

    Science.gov (United States)

    Shcherbakova, O. V.; Pan, A. V.; Wang, J. L.; Shcherbakov, A. V.; Dou, S. X.; Wexler, D.; Babić, E.; Jerčinović, M.; Husnjak, O.

    2008-01-01

    In this paper we report the results of an extended study of the effect of sugar doping on the structural and electromagnetic properties of MgB2 superconductors. High values of the upper critical field (Bc2) of 36 T and the irreversibility field (Birr) of 27 T have been estimated at the temperature of 5 K in a bulk MgB2 sample with the addition of 10 wt% of sugar. The critical current density (Jc(Ba)) of sugar-doped samples has been significantly improved in the high field region. The value of transport Jc has reached as high as 108 A m-2 at 10 T and 5 K for Fe-sheathed sugar-doped MgB2 wire. The analysis of the pinning mechanism in the samples investigated indicated that dominant vortex pinning occurs on the surface type of pinning defects, such as grain boundaries, dislocations, stacking faults etc, for both pure and doped MgB2. In sugar-doped samples, pinning is governed by numerous crystal lattice defects, which appear in MgB2 grains as a result of crystal lattice distortion caused by carbon substitution for boron and nano-inclusions. The drastically improved superconducting properties of sugar-doped samples are also attributed to the highly homogeneous distribution and enhanced reactivity of this dopant with host Mg and B powders. The results of this work suggest that sugar is the optimal source of carbon for doping MgB2 superconductor, especially for application at high magnetic fields.

  12. Dietary Sources of Vitamin B-12 and Their Association with Vitamin B-12 Status Markers in Healthy Older Adults in the B-PROOF Study

    Directory of Open Access Journals (Sweden)

    Elske M. Brouwer-Brolsma

    2015-09-01

    Full Text Available Low vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations between dietary sources of vitamin B-12 (meat, fish and shellfish, eggs, dairy and serum vitamin B-12, using cross-sectional data of 600 Dutch community-dwelling adults (≥65 years. Dietary intake was assessed with a validated food frequency questionnaire. Vitamin B-12 concentrations were measured in serum. Associations were studied over tertiles of vitamin B-12 intake using P for trend, by calculating prevalence ratios (PRs, and splines. Whereas men had significantly higher vitamin B-12 intakes than women (median (25th–75th percentile: 4.18 (3.29–5.38 versus 3.47 (2.64–4.40 μg/day, serum vitamin B-12 did not differ between the two sexes (mean ± standard deviation (SD: 275 ± 104 pmol/L versus 290 ± 113 pmol/L. Higher intakes of dairy, meat, and fish and shellfish were significantly associated with higher serum vitamin B-12 concentrations, where meat and dairy—predominantly milk were the most potent sources. Egg intake did not significantly contribute to higher serum vitamin B-12 concentrations. Thus, dairy and meat were the most important contributors to serum vitamin B-12, followed by fish and shellfish.

  13. APOGEE Chemical Abundances of the Sagittarius Dwarf Galaxy System

    Science.gov (United States)

    Hasselquist, Sten; Shetrone, Matthew D.; Smith, Verne V.; Holtzman, Jon A.; McWilliam, Andrew; APOGEE Team

    2018-06-01

    The Apache Point Observatory Galactic Evolution Experiment provides the opportunity of measuring elemental abundances for C, N, O, Na, Mg, Al, Si, P, K, Ca, V, Cr, Mn, Fe, Co, and Ni in vast numbers of stars. We analyze the chemical-abundance patterns of these elements for 158 red giant stars belonging to the Sagittarius dwarf galaxy (Sgr). This is the largest sample of Sgr stars with detailed chemical abundances, and it is the first time that C, N, P, K, V, Cr, Co, and Ni have been studied at high resolution in this galaxy. We find that the Sgr stars with [Fe/H] > -0.8 are deficient in all elemental abundance ratios (expressed as [X/Fe]) relative to the Milky Way, suggesting that the Sgr stars observed today were formed from gas that was less enriched by Type II SNe than stars formed in the Milky Way. By examining the relative deficiencies of the hydrostatic (O, Na, Mg, and Al) and explosive (Si, P, K, and Mn) elements, our analysis supports the argument that previous generations of Sgr stars were formed with a top-light initial mass function, one lacking the most massive stars that would normally pollute the interstellar medium with the hydrostatic elements. We use a simple chemical-evolution model, flexCE, to further support our claim and conclude that recent stellar generations of Fornax and the Large Magellanic Cloud could also have formed according to a top-light initial mass function. We then exploit the unique chemical abundance patters of the Sgr core to trace stars belonging to the Sgr tidal streams elsewhere in the Milky Way.

  14. FLICKERING OF 1.3 cm SOURCES IN SGR B2: TOWARD A SOLUTION TO THE ULTRACOMPACT H II REGION LIFETIME PROBLEM

    Energy Technology Data Exchange (ETDEWEB)

    De Pree, C. G.; Monsrud, A. [Agnes Scott College, 141 East College Avenue, Decatur, GA 30030 (United States); Peters, T. [Institut für Theoretische Physik, Universität Zürich, CH-8057 Zürich (Switzerland); Mac Low, M.-M. [American Museum of Natural History, New York, NY 10024 (United States); Wilner, D. J.; Keto, E. R. [Harvard-Smithsonian CfA, Cambridge, MA 02138 (United States); Goss, W. M. [National Radio Astronomy Observatory, Socorro, NM 87801 (United States); Galván-Madrid, R. [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany); Klessen, R. S. [Zentrum für Astronomie, Institut für Theoretische Astrophysik, Universität Heidelberg, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany)

    2014-02-01

    Accretion flows onto massive stars must transfer mass so quickly that they are themselves gravitationally unstable, forming dense clumps and filaments. These density perturbations interact with young massive stars, emitting ionizing radiation, alternately exposing and confining their H II regions. As a result, the H II regions are predicted to flicker in flux density over periods of decades to centuries rather than increase monotonically in size as predicted by simple Spitzer solutions. We have recently observed the Sgr B2 region at 1.3 cm with the Very Large Array in its three hybrid configurations (DnC, CnB, and BnA) at a resolution of ∼0.''25. These observations were made to compare in detail with matched continuum observations from 1989. At 0.''25 resolution, Sgr B2 contains 41 ultracompact (UC) H II regions, 6 of which are hypercompact. The new observations of Sgr B2 allow comparison of relative peak flux densities for the H II regions in Sgr B2 over a 23 year time baseline (1989-2012) in one of the most source-rich massive star forming regions in the Milky Way. The new 1.3 cm continuum images indicate that four of the 41 UC H II regions exhibit significant changes in their peak flux density, with one source (K3) dropping in peak flux density, and the other three sources (F10.303, F1, and F3) increasing in peak flux density. The results are consistent with statistical predictions from simulations of high mass star formation, suggesting that they offer a solution to the lifetime problem for UC H II regions.

  15. Thermal stability of hexagonal OsB2

    International Nuclear Information System (INIS)

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; Cullen, David A.; Andrew Payzant, E.

    2014-01-01

    The synthesis of novel hexagonal ReB 2 -type OsB 2 ceramic powder was performed by high energy ball milling of elemental Os and B powders. Two different sources of B powder have been used for this mechanochemical synthesis. One B powder consisted of a mixture of amorphous and crystalline phases and a mixture of 10 B and 11 B isotopes with a fine particle size, while another B powder was a purely crystalline (rhombohedral) material consisting of enriched 11 B isotope with coarse particle size. The same Os powder was used for the synthesis in both cases. It was established that, in the first case, the hexagonal OsB 2 phase was the main product of synthesis with a small quantity of Os 2 B 3 phase present after synthesis as an intermediate product. In the second case, where coarse crystalline 11 B powder was used as a raw material, only Os 2 B 3 boride was synthesized mechanochemically. The thermal stability of hexagonal OsB 2 powder was studied by heating under argon up to 876 °C and cooling in vacuo down to −225 °C. During the heating, the sacrificial reaction 2OsB 2 +3O 22Os+2B 2 O 3 took place due to presence of O 2 /water vapor molecules in the heating chamber, resulting in the oxidation of B atoms and formation of B 2 O 3 and precipitation of Os metal out of the OsB 2 lattice. As a result of such phase changes during heating, the lattice parameters of hexagonal OsB 2 changed significantly. The shrinkage of the a lattice parameter was recorded in 276–426 °C temperature range upon heating, which was attributed to the removal of B atoms from the OsB 2 lattice due to oxidation followed by the precipitation of Os atoms and formation of Os metal. While significant structural changes occurred upon heating due to presence of O 2 , the hexagonal OsB 2 ceramic demonstrated good phase stability upon cooling in vacuo with linear shrinkage of the lattice parameters and no phase changes detected during cooling. - Graphical abstract: The in situ high temperature XRD

  16. Vitamin B2 (riboflavin content in cereal products

    Directory of Open Access Journals (Sweden)

    Soňa Škrovánková

    2010-01-01

    Full Text Available Vitamin B2 (riboflavin is a water-soluble essential vitamin. Nowadays an increased risk for riboflavin deficiency may be seen in people on special diets (diabetes mellitus, smokers or heavy alcohol drinkers. In the Czech diet the main sources of the vitamin intake are milk and dairy products followed by cereals and meat. Cereals are good source of this vitamin as it is widely and regularly consumed in different forms. Analyses of the vitamin B2 content in different types of cereal products (flours, breads, pastries, breakfast cereals, cooked pasta of Czech origin using HPLC with reversed phase and UV detection were done. The vitamin B2 content of chosen cereal products decreased in this progression: enriched wholemeal breakfast cereals (the best source of the vitamin, enriched wheat flours, breads – rye and wholemeal wheat breads, whole wheat and spelt flours, wheat bread, cooked whole wheat and rye spaghetti, wheat and multigrain pastries and finally scoured wheat flours.

  17. Exposures to natural radiation sources. Annex B

    International Nuclear Information System (INIS)

    1982-01-01

    The assessment of the radiation doses from natural sources in humans is presented. Both external sources of extraterrestrial origin (cosmic rays) and of terrestrial origin, and internal sources, comprising the naturally-occurring radionuclides which are taken into the human body, are discussed. This Annex is to a large extent a summary of Annex B of the 1977 report of the Committee. The doses due to the radon isotopes and to their short-lived decay products are briefly reviewed.

  18. E-hubs: the new B2B (business-to-business) marketplaces.

    Science.gov (United States)

    Kaplan, S; Sawhney, M

    2000-01-01

    Electronic hubs--Internet-based intermediaries that host electronic marketplaces and mediate transactions among businesses--are generating a lot of interest. Companies like Ariba, Chemdex, and Commerce One have already attained breathtaking stock market capitalizations. Venture capitalists are pouring money into more business-to-business start-ups. Even industrial stalwarts like GM and Ford are making plans to set up their own Web markets. As new entrants with new business models pour into the business-to-business space, it's increasingly difficult to make sense of the landscape. This article provides a blueprint of the e-hub arena. The authors start by looking at the two dimensions of purchasing: what businesses buy--manufacturing inputs or operating inputs--and how they buy--through systematic sourcing or spot sourcing. They classify B2B e-hubs into four categories: MRO hubs, yield managers, exchanges, and catalog hubs, and they discuss each type in detail. Drilling deeper into this B2B matrix, the authors look at how e-hubs create value--through aggregation and matching--and explain when each mechanism works best. They also examine the biases of e-hubs. Although many e-hubs are neutral--they're operated by independent third parties--some favor the buyers or sellers. The authors explain the differences and discuss the pros and cons of each position. The B2B marketplace is changing rapidly. This framework helps buyers, sellers, and market makers navigate the landscape by explaining what the different hubs do and how they add the most value.

  19. 40 CFR Table 4 to Subpart Dd of... - Tank Control Levels for Tanks at New Affected Sources as Required by 40 CFR 63.685(b)(2)

    Science.gov (United States)

    2010-07-01

    ... Affected Sources as Required by 40 CFR 63.685(b)(2) 4 Table 4 to Subpart DD of Part 63 Protection of... Hazardous Air Pollutants from Off-Site Waste and Recovery Operations Pt. 63, Subpt. DD, Table 4 Table 4 to Subpart DD of Part 63—Tank Control Levels for Tanks at New Affected Sources as Required by 40 CFR 63.685(b...

  20. Interaction between the SNR Sagittarius A East and the 50-km s-1 Molecular Cloud

    International Nuclear Information System (INIS)

    Tsuboi, Masato; Okumura, Sachiko K; Miyazaki, Atsushi

    2006-01-01

    We performed high-resolution observations of the Galactic Center 50-km s -1 molecular cloud in the CS J = 1 - 0 line using the Nobeyama Millimeter Array. The 50-km s -1 molecular cloud corresponds to a break in the Sagittarius (Sgr) A east shell. A very broad and negative velocity wing feature is detected at an apparent contact spot between the molecular cloud and the Sgr A east shell. The velocity width of the wing feature is over 50-km s -1 . The width is three times wider than those of typical Galactic Center clouds. This strongly suggests that the shell is interacting physically with the molecular cloud. The asymmetric velocity profile of the wing feature indicates that the Sgr A east shell expands and crashes into the far side of the molecular cloud. About 50 clumps are identified in the cloud using CLUMPFIND. The velocity width-size relation and the mass spectrum of clumps in the cloud are similar to those in Central Molecular Zone (CMZ)

  1. The Power of B2B Brands : A case study of how B2B companies in the forest industry can communicate sustainability through their Brand

    OpenAIRE

    Bålfors, Joakim; Ståhlspets, Johan

    2016-01-01

    Today’s B2B companies operate in a global business world that is characterised by product homogenisation and intense competition. Finding sources for differentiation and consequently competitive advantage is a concern that no company with a long-term horizon can ignore. The development of the brand, recognized as a strategic asset, has created new ways of conducting beneficial marketing management, which can lead to differentiation from competitors and create conditions for company success. T...

  2. CONSTRAINING THE STRUCTURE OF SAGITTARIUS A*'s ACCRETION FLOW WITH MILLIMETER VERY LONG BASELINE INTERFEROMETRY CLOSURE PHASES

    Energy Technology Data Exchange (ETDEWEB)

    Broderick, Avery E [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Fish, Vincent L; Doeleman, Sheperd S [Massachusetts Institute of Technology, Haystack Observatory, Route 40, Westford, MA 01886 (United States); Loeb, Abraham [Institute for Theory and Computation, Harvard University, Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2011-09-01

    Millimeter wave very long baseline interferometry (mm-VLBI) provides access to the emission region surrounding Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, on sub-horizon scales. Recently, a closure phase of 0{sup 0} {+-} 40{sup 0} was reported on a triangle of Earth-sized baselines (SMT-CARMA-JCMT) representing a new constraint upon the structure and orientation of the emission region, independent from those provided by the previously measured 1.3 mm-VLBI visibility amplitudes alone. Here, we compare this to the closure phases associated with a class of physically motivated, radiatively inefficient accretion flow models and present predictions for future mm-VLBI experiments with the developing Event Horizon Telescope (EHT). We find that the accretion flow models are capable of producing a wide variety of closure phases on the SMT-CARMA-JCMT triangle and thus not all models are consistent with the recent observations. However, those models that reproduce the 1.3 mm-VLBI visibility amplitudes overwhelmingly have SMT-CARMA-JCMT closure phases between {+-}30{sup 0}, and are therefore broadly consistent with all current mm-VLBI observations. Improving station sensitivity by factors of a few, achievable by increases in bandwidth and phasing together multiple antennas at individual sites, should result in physically relevant additional constraints upon the model parameters and eliminate the current 180{sup 0} ambiguity on the source orientation. When additional stations are included, closure phases of order 45{sup 0}-90{sup 0} are typical. In all cases, the EHT will be able to measure these with sufficient precision to produce dramatic improvements in the constraints upon the spin of Sgr A*.

  3. Extreme ultraviolet spectroscopy of G191-B2B - Direct observation of ionization edges

    Science.gov (United States)

    Wilkinson, Erik; Green, James C.; Cash, Webster

    1992-01-01

    We present the first spectrum of the hot, DA white dwarf G191-B2B (wd 0501 + 527) between 200 and 330 A. The spectrum, which has about 2 A resolution, was obtained with a sounding rocket-borne, grazing incidence spectrograph. The spectrum shows no evidence of He II, the expected primary opacity source in this wavelength region. Three ionization edges and one absorption feature were observed and are suggestive of O III existing in the photosphere of G191-B2B. Also noted is a broad spectral depression that may result from Fe VI in the photosphere.

  4. Remaining Sites Verification Package for the 126-B-2, 183-B Clearwells

    International Nuclear Information System (INIS)

    Dittmer, L.M.

    2007-01-01

    The 126-B-2, 183-B Clearwells were built as part of the 183-B Water Treatment Facility and are composed of 2 covered concrete reservoirs. The bulk of the water stored in the clearwells was used as process water to cool the 105-B Reactor and as a source of potable water. Residual conditions were determined to meet the remedial action objectives specified in the Remaining Sites ROD through an evaluation of the available process knowledge. The results of the evaluation do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also indicate that residual concentrations are protective of groundwater and the Columbia River.

  5. Sources of b quarks at the Fermilab Tevatron and their correlations

    International Nuclear Information System (INIS)

    Field, R.D.

    2002-01-01

    The leading-logarithm order QCD hard scattering Monte Carlo models of HERWIG, ISAJET, and PYTHIA are used to study the sources of b quarks at the Fermilab Tevatron. The reactions responsible for producing b and b(bar sign) quarks are separated into three categories: flavor creation, flavor excitation, and parton-shower or fragmentation. Flavor creation corresponds to the production of a bb(bar sign) pair by gluon fusion or by annihilation of light quarks, while flavor excitation corresponds to a b or b(bar sign) quark being knocked out of the initial state by a gluon or a light quark or antiquark. The third source occurs when a bb(bar sign) pair is produced within a parton shower or during the fragmentation process of a gluon or a light quark or antiquark (includes gluon splitting). The QCD Monte Carlo models indicate that all three sources of b quarks are important at the Tevatron and when combined they qualitatively describe the inclusive cross-section data. Correlations between the b and b(bar sign) quark are very different for the three sources and can be used to isolate the individual contributions

  6. Thermal stability of hexagonal OsB{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Zhilin [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816 (United States); Blair, Richard G. [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816 (United States); Department of Physics, University of Central Florida, Orlando, FL 32816 (United States); Orlovskaya, Nina, E-mail: Nina.Orlovskaya@ucf.edu [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816 (United States); Cullen, David A. [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Andrew Payzant, E. [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2014-11-15

    The synthesis of novel hexagonal ReB{sub 2}-type OsB{sub 2} ceramic powder was performed by high energy ball milling of elemental Os and B powders. Two different sources of B powder have been used for this mechanochemical synthesis. One B powder consisted of a mixture of amorphous and crystalline phases and a mixture of {sup 10}B and {sup 11}B isotopes with a fine particle size, while another B powder was a purely crystalline (rhombohedral) material consisting of enriched {sup 11}B isotope with coarse particle size. The same Os powder was used for the synthesis in both cases. It was established that, in the first case, the hexagonal OsB{sub 2} phase was the main product of synthesis with a small quantity of Os{sub 2}B{sub 3} phase present after synthesis as an intermediate product. In the second case, where coarse crystalline {sup 11}B powder was used as a raw material, only Os{sub 2}B{sub 3} boride was synthesized mechanochemically. The thermal stability of hexagonal OsB{sub 2} powder was studied by heating under argon up to 876 °C and cooling in vacuo down to −225 °C. During the heating, the sacrificial reaction 2OsB{sub 2}+3O{sub 2}→2Os+2B{sub 2}O{sub 3} took place due to presence of O{sub 2}/water vapor molecules in the heating chamber, resulting in the oxidation of B atoms and formation of B{sub 2}O{sub 3} and precipitation of Os metal out of the OsB{sub 2} lattice. As a result of such phase changes during heating, the lattice parameters of hexagonal OsB{sub 2} changed significantly. The shrinkage of the a lattice parameter was recorded in 276–426 °C temperature range upon heating, which was attributed to the removal of B atoms from the OsB{sub 2} lattice due to oxidation followed by the precipitation of Os atoms and formation of Os metal. While significant structural changes occurred upon heating due to presence of O{sub 2}, the hexagonal OsB{sub 2} ceramic demonstrated good phase stability upon cooling in vacuo with linear shrinkage of the lattice

  7. Type B package for the transport of large medical and industrial sources

    International Nuclear Information System (INIS)

    Brown, Darrell Dwaine; Noss, Philip W.

    2010-01-01

    AREVA Federal Services LLC, under contract to the Los Alamos National Laboratory's Offsite Source Recovery Project, is developing a new Type B(U)-96 package for the transport of unwanted or abandoned high activity gamma and neutron radioactive sealed sources (sources). The sources were used primarily in medical or industrial devices, and are of domestic (USA) or foreign origin. To promote public safety and mitigate the possibility of loss or misuse, the Offsite Source Recovery Project is recovering and managing sources worldwide. The package, denoted the LANL-B, is designed to accommodate the sources within an internal gamma shield. The sources are located either in the IAEA's Long Term Storage Shield (LTSS), or within intact medical or industrial irradiation devices. As the sources are already shielded separately, the package does not include any shielding of its own. A particular challenge in the design of the LANL-B has been weight. Since the LTSS shield weighs approximately 5,000 lb (2,270 kg), and the total package gross weight must be limited to 10,000 lb (4,540 kg), the net weight of the package was limited to 5,000 lb, for an efficiency of 50% (i.e., the payload weight is 50% of the gross weight of the package). This required implementation of a light-weight bell-jar concept, in which the containment takes the form of a vertical bell which is bolted to a base. A single impact limiter is used on the bottom, to protect the elastomer seals and bolted joint. A top-end impact is mitigated by the deformation of a tori spherically-shaped head. Impacts in various orientations on the bottom end are mitigated by a cylindrical, polyurethane foam-filled impact limiter. Internally, energy is absorbed using honeycomb blocks at each end, which fill the torispherical head volumes. As many of the sources are considered to be in normal form, the LANL-B package offers leak-tight containment using an elastomer seal at the joint between the bell and the base, as well as on the

  8. Image značky L´Oréal Professionnel v segmentu B2B

    OpenAIRE

    Novotná, Barbora

    2012-01-01

    I have focused on the problematic of L'Oréal Professionnel brand image, which is the brand of professional haircare cosmetics in B2B segment. B2B segment is the key source of income of this brand. In theoretical part I have explained terms like brand, brand image and brand identity, marketing mix, marketing strategy, consumer behaviour, brand knowledge etc. In practical part, I have focused on the development of L'Oréal Professionnel brand as well as the development of its marketing strategy ...

  9. Satisfaction with virtual communities in B2B financial services: social dynamics, content and technology

    NARCIS (Netherlands)

    Chompis, E.; Bons, R.W.H.; van den Hooff, B.J.; Feldberg, J.F.M.; Horn, H.

    2014-01-01

    This study explores satisfaction with Virtual Communities in a Financial Services setting. Based on Expectancy Value Theory and the concept of Experiential Value we hypothesize that three sources of value drive user satisfaction in a B2B-VC: social ties, content and technology. We propose a

  10. The Vaporization of B2O3(l) to B2O3(g) and B2O2(g)

    Science.gov (United States)

    Jacobson, Nathan S.; Myers, Dwight L.

    2011-01-01

    The vaporization of B2O3 in a reducing environment leads to formation of both B2O3(g) and B2O2(g). While formation of B2O3(g) is well understood, many questions about the formation of B2O2(g) remain. Previous studies using B(s) + B2O3(l) have led to inconsistent thermodynamic data. In this study, it was found that after heating, B(s) and B2O3(l) appear to separate and variations in contact area likely led to the inconsistent vapor pressures of B2O2(g). To circumvent this problem, an activity of boron is fixed with a two-phase mixture of FeB and Fe2B. Both second and third law enthalpies of formation were measured for B2O2(g) and B2O3(g). From these the enthalpies of formation at 298.15 K are calculated to be -479.9 +/- 41.5 kJ/mol for B2O2(g) and -833.4 +/- 13.1 kJ/mol for B2O3(g). Ab initio calculations to determine the enthalpies of formation of B2O2(g) and B2O3(g) were conducted using the W1BD composite method and show good agreement with the experimental values.

  11. Cost Comparison of B-1B Non-Mission-Capable Drivers Using Finite Source Queueing with Spares

    Science.gov (United States)

    2012-09-06

    COMPARISON OF B-1B NON-MISSION-CAPABLE DRIVERS USING FINITE SOURCE QUEUEING WITH SPARES GRADUATE RESEARCH PAPER Presented to the Faculty...step into the lineup making large-number approximations unusable. Instead, a finite source queueing model including spares is incorporated...were reported as flying time accrued since last occurrence. Service time was given in both start-stop format and MX man-hours utilized. Service time was

  12. Thermal stability of hexagonal OsB2

    Science.gov (United States)

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; Cullen, David A.; Andrew Payzant, E.

    2014-11-01

    The synthesis of novel hexagonal ReB2-type OsB2 ceramic powder was performed by high energy ball milling of elemental Os and B powders. Two different sources of B powder have been used for this mechanochemical synthesis. One B powder consisted of a mixture of amorphous and crystalline phases and a mixture of 10B and 11B isotopes with a fine particle size, while another B powder was a purely crystalline (rhombohedral) material consisting of enriched 11B isotope with coarse particle size. The same Os powder was used for the synthesis in both cases. It was established that, in the first case, the hexagonal OsB2 phase was the main product of synthesis with a small quantity of Os2B3 phase present after synthesis as an intermediate product. In the second case, where coarse crystalline 11B powder was used as a raw material, only Os2B3 boride was synthesized mechanochemically. The thermal stability of hexagonal OsB2 powder was studied by heating under argon up to 876 °C and cooling in vacuo down to -225 °C. During the heating, the sacrificial reaction 2OsB2+3O22Os+2B2O3 took place due to presence of O2/water vapor molecules in the heating chamber, resulting in the oxidation of B atoms and formation of B2O3 and precipitation of Os metal out of the OsB2 lattice. As a result of such phase changes during heating, the lattice parameters of hexagonal OsB2 changed significantly. The shrinkage of the a lattice parameter was recorded in 276-426 °C temperature range upon heating, which was attributed to the removal of B atoms from the OsB2 lattice due to oxidation followed by the precipitation of Os atoms and formation of Os metal. While significant structural changes occurred upon heating due to presence of O2, the hexagonal OsB2 ceramic demonstrated good phase stability upon cooling in vacuo with linear shrinkage of the lattice parameters and no phase changes detected during cooling.

  13. Chemical abundances of giant stars in NGC 5053 and NGC 5634, two globular clusters associated with the Sagittarius dwarf spheroidal galaxy?

    Science.gov (United States)

    Sbordone, L.; Monaco, L.; Moni Bidin, C.; Bonifacio, P.; Villanova, S.; Bellazzini, M.; Ibata, R.; Chiba, M.; Geisler, D.; Caffau, E.; Duffau, S.

    2015-07-01

    Context. The tidal disruption of the Sagittarius dwarf spheroidal galaxy (Sgr dSph) is producing the most prominent substructure in the Milky Way (MW) halo, the Sagittarius Stream. Aside from field stars, it is suspected that the Sgr dSph has lost a number of globular clusters (GC). Many Galactic GC are thought to have originated in the Sgr dSph. While for some candidates an origin in the Sgr dSph has been confirmed owing to chemical similarities, others exist whose chemical composition has never been investigated. Aims: NGC 5053 and NGC 5634 are two of these scarcely studied Sgr dSph candidate-member clusters. To characterize their composition we analyzed one giant star in NGC 5053, and two in NGC 5634. Methods: We analyze high-resolution and signal-to-noise spectra by means of the MyGIsFOS code, determining atmospheric parameters and abundances for up to 21 species between O and Eu. The abundances are compared with those of MW halo field stars, of unassociated MW halo globulars, and of the metal-poor Sgr dSph main body population. Results: We derive a metallicity of [Fe ii/H] = -2.26 ± 0.10 for NGC 5053, and of [Fe i/H] = -1.99 ± 0.075 and -1.97 ± 0.076 for the two stars in NGC 5634. This makes NGC 5053 one of the most metal-poor globular clusters in the MW. Both clusters display an α enhancement similar to the one of the halo at comparable metallicity. The two stars in NGC 5634 clearly display the Na-O anticorrelation widespread among MW globulars. Most other abundances are in good agreement with standard MW halo trends. Conclusions: The chemistry of the Sgr dSph main body populations is similar to that of the halo at low metallicity. It is thus difficult to discriminate between an origin of NGC 5053 and NGC 5634 in the Sgr dSph, and one in the MW. However, the abundances of these clusters do appear closer to that of Sgr dSph than of the halo, favoring an origin in the Sgr dSph system. Appendix A is available in electronic form at http

  14. Qualitative and quantitative analysis of Dibenzofuran, Alkyldibenzofurans, and Benzo[b]naphthofurans in crude oils and source rock extracts

    Science.gov (United States)

    Meijun Li,; Ellis, Geoffrey S.

    2015-01-01

    Dibenzofuran (DBF), its alkylated homologues, and benzo[b]naphthofurans (BNFs) are common oxygen-heterocyclic aromatic compounds in crude oils and source rock extracts. A series of positional isomers of alkyldibenzofuran and benzo[b]naphthofuran were identified in mass chromatograms by comparison with internal standards and standard retention indices. The response factors of dibenzofuran in relation to internal standards were obtained by gas chromatography-mass spectrometry analyses of a set of mixed solutions with different concentration ratios. Perdeuterated dibenzofuran and dibenzothiophene are optimal internal standards for quantitative analyses of furan compounds in crude oils and source rock extracts. The average concentration of the total DBFs in oils derived from siliciclastic lacustrine rock extracts from the Beibuwan Basin, South China Sea, was 518 μg/g, which is about 5 times that observed in the oils from carbonate source rocks in the Tarim Basin, Northwest China. The BNFs occur ubiquitously in source rock extracts and related oils of various origins. The results of this work suggest that the relative abundance of benzo[b]naphthofuran isomers, that is, the benzo[b]naphtho[2,1-d]furan/{benzo[b]naphtho[2,1-d]furan + benzo[b]naphtho[1,2-d]furan} ratio, may be a potential molecular geochemical parameter to indicate oil migration pathways and distances.

  15. Ultraviolet-B radiation enhancement in dielectric barrier discharge based xenon chloride exciplex source by air

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, P., E-mail: pgulati1512@gmail.com [CSIR-Central Electronics Engineering Research Institute (CSIR-CEERI), Pilani, Rajasthan-333031 (India); Department of Physics, Banasthali University, P.O. Banasthali Vidyapith, Rajasthan 304022 (India); Prakash, R.; Pal, U. N.; Kumar, M. [CSIR-Central Electronics Engineering Research Institute (CSIR-CEERI), Pilani, Rajasthan-333031 (India); Vyas, V. [Department of Physics, Banasthali University, P.O. Banasthali Vidyapith, Rajasthan 304022 (India)

    2014-07-07

    A single barrier dielectric barrier discharge tube of quartz with multi-strip Titanium-Gold (Ti-Au) coatings have been developed and utilized for ultraviolet-B (UV-B) radiation production peaking at wavelength 308 nm. The observed radiation at this wavelength has been examined for the mixtures of the Xenon together with chlorine and air admixtures. The gas mixture composition, chlorine gas content, total gas pressure, and air pressure dependency of the UV intensity, has been analyzed. It is found that the larger concentration of Cl{sub 2} deteriorates the performance of the developed source and around 2% Cl{sub 2} in this source produced optimum results. Furthermore, an addition of air in the xenon and chlorine working gas environment leads to achieve same intensity of UV-B light but at lower working gas pressure where significant amount of gas is air.

  16. Ultraviolet-B radiation enhancement in dielectric barrier discharge based xenon chloride exciplex source by air

    Science.gov (United States)

    Gulati, P.; Prakash, R.; Pal, U. N.; Kumar, M.; Vyas, V.

    2014-07-01

    A single barrier dielectric barrier discharge tube of quartz with multi-strip Titanium-Gold (Ti-Au) coatings have been developed and utilized for ultraviolet-B (UV-B) radiation production peaking at wavelength 308 nm. The observed radiation at this wavelength has been examined for the mixtures of the Xenon together with chlorine and air admixtures. The gas mixture composition, chlorine gas content, total gas pressure, and air pressure dependency of the UV intensity, has been analyzed. It is found that the larger concentration of Cl2 deteriorates the performance of the developed source and around 2% Cl2 in this source produced optimum results. Furthermore, an addition of air in the xenon and chlorine working gas environment leads to achieve same intensity of UV-B light but at lower working gas pressure where significant amount of gas is air.

  17. Solo dwarfs I: survey introduction and first results for the Sagittarius dwarf irregular galaxy

    Science.gov (United States)

    Higgs, C. R.; McConnachie, A. W.; Irwin, M.; Bate, N. F.; Lewis, G. F.; Walker, M. G.; Côté, P.; Venn, K.; Battaglia, G.

    2016-05-01

    We introduce the Solitary Local dwarfs survey (Solo), a wide-field photometric study targeting every isolated dwarf galaxy within 3 Mpc of the Milky Way. Solo is based on (u)gi multiband imaging from Canada-France-Hawaii Telescope/MegaCam for northern targets, and Magellan/Megacam for southern targets. All galaxies fainter than MV ≃ -18 situated beyond the nominal virial radius of the Milky Way and M31 (≳300 kpc) are included in this volume-limited sample, for a total of 42 targets. In addition to reviewing the survey goals and strategy, we present results for the Sagittarius dwarf irregular galaxy (Sag DIG), one of the most isolated, low-mass galaxies, located at the edge of the Local Group. We analyse its resolved stellar populations and their spatial distributions. We provide updated estimates of its central surface brightness and integrated luminosity, and trace its surface brightness profile to a level fainter than 30 mag arcsec-2. Sag DIG is well described by a highly elliptical (disc-like) system following a single component Sérsic model. However, a low-level distortion is present at the outer edges of the galaxy that, were Sag DIG not so isolated, would likely be attributed to some kind of previous tidal interaction. Further, we find evidence of an extremely low level, extended distribution of stars beyond ˜5 arcmin (>1.5 kpc) that suggests Sag DIG may be embedded in a very low-density stellar halo. We compare the stellar and H I structures of Sag DIG, and discuss results for this galaxy in relation to other isolated, dwarf irregular galaxies in the Local Group.

  18. Simultaneous high performance liquid chromatographic analysis of vitamins B1, B2 and B6 in royal jelly

    Directory of Open Access Journals (Sweden)

    Presoto Ana Elisa F

    2004-01-01

    Full Text Available Royal jelly is used as a food supplement, popularly known as rich in B vitamins. The present work has two objectives: firstly, to apply simultaneous quantitative determination by High Performance Liquid Chromatography of thiamin (vitamin B1, riboflavin (vitamin B2 and pyridoxine (vitamin B6 and secondly to compare the obtained data with the Dietary Reference Intake (DRI values. The values obtained showed no thiamin, a range from 20 to 171 ng g-1 of riboflavin and from 408 to 2 188 ng g-1 of pyridoxine in royal jelly. According to the Food and Nutrition Board (2000, the DRI of these vitamins varies from 0.2-1.4 mg for thiamin; 0.3-1.6 mg for riboflavin and 0.1-2.0 mg for pyridoxine, depending on age and sex. According to these recommendations, royal jelly is not a good source of vitamins B1, B2 or B6 as these vitamins appear only on order of ng g-1. The proposed method can be used in routine analysis for royal jelly, having the advantage of being simple, fast and reliable.

  19. High energy X-ray observations of COS-B gamma-ray sources from OSO-8

    Science.gov (United States)

    Dolan, J. F.; Crannell, C. J.; Dennis, B. R.; Frost, K. J.; Orwig, L. E.; Caraveo, P. A.

    1985-01-01

    During the three years between satellite launch in June 1975 and turn-off in October 1978, the high energy X-ray spectrometer on board OSO-8 observed nearly all of the COS-B gamma-ray source positions given in the 2CG catalog (Swanenburg et al., 1981). An X-ray source was detected at energies above 20 keV at the 6-sigma level of significance in the gamma-ray error box containing 2CG342 - 02 and at the 3-sigma level of significance in the error boxes containing 2CG065 + 00, 2CG195 + 04, and 2CG311 - 01. No definite association between the X-ray and gamma-ray sources can be made from these data alone. Upper limits are given for the 2CG sources from which no X-ray flux was detected above 20 keV.

  20. 9Be(d,n)10B-based neutron sources for BNCT

    International Nuclear Information System (INIS)

    Capoulat, M.E.; Herrera, M.S.; Minsky, D.M.; González, S.J.; Kreiner, A.J.

    2014-01-01

    In the frame of accelerator-based BNCT, the 9 Be(d,n) 10 B reaction was investigated as a possible source of epithermal neutrons. In order to determine the configuration in terms of bombarding energy, target thickness and Beam Shaping Assembly (BSA) design that results in the best possible beam quality, a systematic optimization study was carried out. From this study, the optimal configuration resulted in tumor doses ≥40 Gy-Eq, with a maximum value of 51 Gy-Eq at a depth of about 2.7 cm, in a 60 min treatment. The optimal configuration was considered for the treatment planning assessment of a real Glioblastoma Multiforme case. From this, the resulted dose performances were comparable to those obtained with an optimized 7 Li(p,n)-based neutron source, under identical conditions and subjected to the same clinical protocol. - Highlights: • Study of the 9 Be(d,n) 10 B reaction as a source of epithermal neutrons for BNCT. • Evaluation of the optimal configuration of target thickness, deuteron energy and BSA design. • Computational dose assessment for brain tumor treatments using the MCNP code. • Treatment planning assessment of a particular clinical Glioblastoma Multiforme case. • Dose performances were comparable to those obtained with an optimized 7 Li(p,n)-based source

  1. B2B or Not to Be: Does B2B E-Commerce Increase Labour Productivity?

    OpenAIRE

    Bertschek, Irene; Fryges, Helmut; Kaiser, Ulrich

    2004-01-01

    We implement an endogeneous switching-regression model for labour productivity and firms' decision to use business-to-business (B2B) e-commerce. Our approach allows B2B usage to affect any parameter of the labour productivity equation and to properly take account of strategic complementarities between the input factors and B2B usage. Empirical evidence from 1,394 German firms shows that firms using B2B e-commerce have a significantly higher output elasticity with respect to ICT-investment and...

  2. Ge(001):B gas-source molecular beam epitaxy: B surface segregation, hydrogen desorption, and film growth kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H.; Greene, J.E. [Materials Science Department, the Coordinated Science Laboratory and the Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States)

    1999-03-01

    Ultrahigh B-doped Ge(001) layers, with concentrations C{sub B} up to 8{times}10{sup 21} cm{sup {minus}3}, were grown by gas-source molecular beam epitaxy from Ge{sub 2}H{sub 6} and B{sub 2}H{sub 6} at temperatures T{sub s}=325{degree}C (in the surface-reaction-limited regime) and 600{degree}C (in the flux-limited regime). The samples were quenched, D site exchanged for H, and D{sub 2} temperature-programed desorption (TPD) used to determine B coverages {theta}{sub B} as a function of C{sub B} and T{sub s} by comparison with B-adsorbed Ge(001) reference samples with known {theta}{sub B} values. During Ge(001):B film growth, strong surface B segregation to the second layer was observed with surface-to-bulk B concentration ratios ranging up to 6000. The TPD spectra exhibited {alpha}{sub 2} and {alpha}{sub 1} peaks associated with dideuteride and monodeuteride desorption as well as lower-temperature B-induced {alpha}{sub 2}{sup {asterisk}} and {alpha}{sub 1}{sup {asterisk}} peaks associated with deuterium desorption from Ge{sup {asterisk}} surface atoms with B backbonds. Increasing {theta}{sub B} expanded the area under {alpha}{sub 2}{sup {asterisk}} and {alpha}{sub 1}{sup {asterisk}} at the expense of {alpha}{sub 2} and {alpha}{sub 1} and decreased the total D coverage {theta}{sub D}. The TPD results were used to determine the B segregation enthalpy, {minus}0.64 eV, and to explain and model the effects of high B coverages on Ge(001) growth kinetics. At T{sub s}=325{degree}C, where B segregation is kinetically hindered, film deposition rates R{sub Ge} are not a strong function of C{sub B}, exhibiting only a small decrease at C{sub B}{approx_gt}5{times}10{sup 18} cm{sup {minus}3}. However, at T{sub s}=600{degree}C, R{sub Ge} decreases by up to 40{percent} with increasing C{sub B}{approx_gt}1{times}10{sup 18} cm{sup {minus}3}. This is due primarily to the combination of B-induced Ge dimer vacancies and the deactivation of surface dangling bonds caused by charge transfer

  3. Honeycomblike large area LaB6 plasma source for Multi-Purpose Plasma facility

    International Nuclear Information System (INIS)

    Woo, Hyun-Jong; Chung, Kyu-Sun; You, Hyun-Jong; Lee, Myoung-Jae; Lho, Taihyeop; Choh, Kwon Kook; Yoon, Jung-Sik; Jung, Yong Ho; Lee, Bongju; Yoo, Suk Jae; Kwon, Myeon

    2007-01-01

    A Multi-Purpose Plasma (MP 2 ) facility has been renovated from Hanbit mirror device [Kwon et al., Nucl. Fusion 43, 686 (2003)] by adopting the same philosophy of diversified plasma simulator (DiPS) [Chung et al., Contrib. Plasma Phys. 46, 354 (2006)] by installing two plasma sources: LaB 6 (dc) and helicon (rf) plasma sources; and making three distinct simulators: divertor plasma simulator, space propulsion simulator, and astrophysics simulator. During the first renovation stage, a honeycomblike large area LaB 6 (HLA-LaB 6 ) cathode was developed for the divertor plasma simulator to improve the resistance against the thermal shock fragility for large and high density plasma generation. A HLA-LaB 6 cathode is composed of the one inner cathode with 4 in. diameter and the six outer cathodes with 2 in. diameter along with separate graphite heaters. The first plasma is generated with Ar gas and its properties are measured by the electric probes with various discharge currents and magnetic field configurations. Plasma density at the middle of central cell reaches up to 2.6x10 12 cm -3 , while the electron temperature remains around 3-3.5 eV at the low discharge current of less than 45 A, and the magnetic field intensity of 870 G. Unique features of electric property of heaters, plasma density profiles, is explained comparing with those of single LaB 6 cathode with 4 in. diameter in DiPS

  4. Predicted Extension of the Sagittarius Stream to the Milky Way Virial Radius

    Energy Technology Data Exchange (ETDEWEB)

    Dierickx, Marion I. P.; Loeb, Abraham, E-mail: mdierickx@cfa.harvard.edu, E-mail: aloeb@cfa.harvard.edu [Astronomy Department, Harvard University, 60 Garden Street, Cambridge, MA 02138 (United States)

    2017-02-10

    The extensive span of the Sagittarius (Sgr) stream makes it a promising tool for studying the gravitational potential of the Milky Way (MW). Characterizing its stellar kinematics can constrain halo properties and provide a benchmark for the paradigm of galaxy formation from cold dark matter. Accurate models of the disruption dynamics of the Sgr progenitor are necessary to employ this tool. Using a combination of analytic modeling and N -body simulations, we build a new model of the Sgr orbit and resulting stellar stream. In contrast to previous models, we simulate the full infall trajectory of the Sgr progenitor from the time it first crossed the MW virial radius 8 Gyr ago. An exploration of the parameter space of initial phase-space conditions yields tight constraints on the angular momentum of the Sgr progenitor. Our best-fit model is the first to accurately reproduce existing data on the 3D positions and radial velocities of the debris detected 100 kpc away in the MW halo. In addition to replicating the mapped stream, the simulation also predicts the existence of several arms of the Sgr stream extending to hundreds of kiloparsecs. The two most distant stars known in the MW halo coincide with the predicted structure. Additional stars in the newly predicted arms can be found with future data from the Large Synoptic Survey Telescope. Detecting a statistical sample of stars in the most distant Sgr arms would provide an opportunity to constrain the MW potential out to unprecedented Galactocentric radii.

  5. Operation of a Dudnikov type Penning source with LaB/sub 6/ cathodes

    International Nuclear Information System (INIS)

    Leung, K.N.; DeVries, G.J.; Ehlers, K.W.

    1986-10-01

    The Dudnikov type Penning source has been operated successfully with LaB 6 cathodes in a cesium-free discharge. It is found that the extracted H - current density is comparable to that of the cesium-mode operation and H - current density of 350 mA/cm 2 have been obtained for an arc current of 55 A. The H - yield is closely related to the source geometry and the applied magnetic field. Experimental results demonstrate that the majority of the H - ions extracted are formed by volume processes in this type of source operation

  6. B11 NMR in the layered diborides OsB2 and RuB2

    Science.gov (United States)

    Suh, B. J.; Zong, X.; Singh, Y.; Niazi, A.; Johnston, D. C.

    2007-10-01

    B11 nuclear magnetic resonance (NMR) measurements have been performed on B11 enriched OsB2 and RuB2 polycrystalline powder samples in an external field of 4.7T and in the temperature range, 4.2KOsB2 and RuB2 , respectively. The experimental results indicate that a p character dominates the conduction electron wave function at the B site with a negligibly small s character in both compounds.

  7. The Metal-poor non-Sagittarius (?) Globular Cluster NGC 5053: Orbit and Mg, Al, and Si Abundances

    Science.gov (United States)

    Tang, Baitian; Fernández-Trincado, J. G.; Geisler, Doug; Zamora, Olga; Mészáros, Szabolcs; Masseron, Thomas; Cohen, Roger E.; García-Hernández, D. A.; Dell’Agli, Flavia; Beers, Timothy C.; Schiavon, Ricardo P.; Sohn, Sangmo Tony; Hasselquist, Sten; Robin, Annie C.; Shetrone, Matthew; Majewski, Steven R.; Villanova, Sandro; Schiappacasse Ulloa, Jose; Lane, Richard R.; Minnti, Dante; Roman-Lopes, Alexandre; Almeida, Andres; Moreno, E.

    2018-03-01

    Metal-poor globular clusters (GCs) exhibit intriguing Al–Mg anti-correlations and possible Si–Al correlations, which are important clues to decipher the multiple-population phenomenon. NGC 5053 is one of the most metal-poor GCs in the nearby universe and has been suggested to be associated with the Sagittarius (Sgr) dwarf galaxy, due to its similarity in location and radial velocity with one of the Sgr arms. In this work, we simulate the orbit of NGC 5053, and argue against a physical connection between Sgr and NGC 5053. On the other hand, the Mg, Al, and Si spectral lines, which are difficult to detect in the optical spectra of NGC 5053 stars, have been detected in the near-infrared APOGEE spectra. We use three different sets of stellar parameters and codes to derive the Mg, Al, and Si abundances. Regardless of which method is adopted, we see a large Al variation, and a substantial Si spread. Along with NGC 5053, metal-poor GCs exhibit different Mg, Al, and Si variations. Moreover, NGC 5053 has the lowest cluster mass among the GCs that have been identified to exhibit an observable Si spread until now.

  8. TSUNAMI INFORMATION SOURCES PART 2

    Directory of Open Access Journals (Sweden)

    Robert L. Wiegel

    2006-01-01

    Full Text Available Tsunami Information Sources (Robert L. Wiegel, University of California, Berkeley, CA, UCB/HEL 2005-1, 14 December 2005, 115 pages, is available in printed format, and on a diskette. It is also available in electronic format at the Water Resources Center Archives, University of California, Berkeley, CA http:www.lib.berkeley.edu/WRCA/tsunamis.htmland in the International Journal of The Tsunami Society, Science of Tsunami Hazards (Vol. 24, No. 2, 2006, pp 58-171 at http://www.sthjournal.org/sth6.htm.This is Part 2 of the report. It has two components. They are: 1.(Sections A and B. Sources added since the first report, and corrections to a few listed in the first report. 2.(Sections C and D. References from both the first report and this report, listed in two categories:Section C. Planning and engineering design for tsunami mitigation/protection; adjustments to the hazard; damage to structures and infrastructureSection D. Tsunami propagation nearshore; induced oscillations; runup/inundation (flooding and drawdown.

  9. Archaeology of the Sagittarius galaxy by means of its stellar clusters

    Science.gov (United States)

    Moni Bidin, C.

    2017-07-01

    The Sagittarius dwarf spheroidal (Sgr dSph) galaxy is a Milky Way satellite currently merging with the parent system. This small galaxy is undergoing disruption due to tidal forces, while stars and clusters lost along the orbit progressively mix with the general Galactic population. The Sgr system is also one of the very few local dSph's known to host stellar clusters, but the census of its cluster population is far from complete. This is very bad, both because the total amount of clusters can help estimating the mass of the original system, and because the age-metallicity relations of the so-far confirmed six members shows an age gap at intermediate ages similar to the well-known gap of the Large Magellanic Cloud. Still, this feature could be due only to the small number of confirmed members. Here we show the status of our project aimed at testing the membership to the Sgr galaxy of a series of candidates proposed in the literature. Our recent spectroscopic studies could exclude the Sgr membership of three candidates, namely Ruprecht 106, NGC 4147, and E 3, although a follow-up study of the latter is ongoing to confirm the previous results. On the other hand, our chemical analysis concluded that NGC 5634 is very likely a member of the Sgr cluster family, and NGC 5053 also could be. Finally, we present our preliminary results of our spectroscopic analysis for the last object, namely AM 4. This candidate is particularly important, because previous estimates of age and metallicity indicate that it closely follow the relation traced by confirmed clusters, but its intermediate age makes it fall exactly at the middle of the supposed age gap.

  10. Marketing Optimization for B2B Market

    OpenAIRE

    Kaynova Tatyana V.

    2012-01-01

    The article presents market definition B2B, the necessity to optimize marketing B2B market, provides a system for B2B-marketing and developed stages of its formation. On this basis it was identified key factors of customer loyalty and are the stages of development of loyalty programs for customers market B2B.

  11. Lattice dynamical and thermodynamical properties of ReB2, RuB2, and OsB2 compounds in the ReB2 structure

    International Nuclear Information System (INIS)

    Deligoz, E.; Colakoglu, K.; Ciftci, Y. O.

    2012-01-01

    Structural and lattice dynamical properties of ReB 2 , RuB 2 , and OsB 2 in the ReB 2 structure are studied in the framework of density functional theory within the generalized gradient approximation. The present results show that these compounds are dynamically stable for the considered structure. The temperature-dependent behaviors of thermodynamical properties such as internal energy, free energy, entropy, and heat capacity are also presented. The obtained results are in good agreement with the available experimental and theoretical data

  12. Emericella astellata, a new producer of aflatoxin B-1, B-2 and sterigmatocystin

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Samson, R.A.; Smedsgaard, Jørn

    2004-01-01

    To report on aflatoxin B-1 and B-2 production from a species of Emericella. Methods and Results: Aflatoxins and sterigmatocystin were determined by high-pressure liquid chromatography (HPLC) with diode array detection and confirmed by HPLC with mass spectrometry detection. Among 30 known species...... of Emericella only one species produced aflatoxin. Strains originating from the same geographical source material had different patterns of aflatoxin and sterigmatocystin production on different media, indicating that epigenetic factors may be involved in the regulation of aflatoxin production. However, two...

  13. B2B myynnin johtaminen ravintola-alalla

    OpenAIRE

    Pajari, Katja

    2014-01-01

    Tämän opinnäytetyön tavoitteena oli selvittää, miten ravintola-alan yrityksissä johdetaan B2B myyntiä. Tarkoituksena oli kartoittaa, miten yrityksissä panostetaan B2B myyntiin ja sen johtamiseen sekä millä tavoin yritysmyyntiä johdetaan. Tutkimus pohjautuu opinnäytetyön tietoperustaan, jossa käsitellään B2B myyntiprosessia ja myynnin johtamista. Työssä käsitellään B2B myyntiä ja selvitetään myyntiprosessin eri vaiheita. Aihe on rajattu koskemaan nimenomaan johtamisen näkökulmaa B2B myynni...

  14. Structural, mechanical, and electronic properties of TaB2, TaB, IrB2, and IrB: First-principle calculations

    International Nuclear Information System (INIS)

    Zhao Wenjie; Wang Yuanxu

    2009-01-01

    First-principle calculations were performed to investigate the structural, elastic, and electronic properties of TaB 2 , TaB, IrB 2 , and IrB. The calculated equilibrium structural parameters, shear modulus, and Young's modulus of TaB 2 are well consistent with the available experimental data, and TaB 2 with P6/mmm space group has stronger directional bonding between ions than WB 2 , OsB 2 , IrN 2 , and PtN 2 . For TaB 2 , the hexagonal P6/mmm structure is more stable than the orthorhombic Pmmn one, while for IrB 2 the orthorhombic Pmmn structure is the most stable one. The high shear modulus of P6/mmm phase TaB 2 is mainly due to the strong covalent π-bonding of B-hexagon in the (0001) plane. Such a B-hexagon network can strongly resist against an applied [112-bar0] (0001) shear deformation. Correlation between the hardness and the elastic constants of TaB 2 was discussed. The band structure shows that P6/mmm phase TaB 2 and Pmmn phase IrB 2 are both metallic. The calculations show that both TaB and IrB are elastically stable with the hexagonal P6 3 /mmc structure. - Elastic constant c 44 of TaB 2 is calculated to be 235 GPa. This value is exceptionally high, exceeding those of WB 2 , OsB 2 , WB 4 , OsN 2 , IrN 2 , and PtN 2 .

  15. SACALCCYL, Calculates the average solid angle subtended by a volume; SACALC2B, Calculates the average solid angle for source-detector geometries

    International Nuclear Information System (INIS)

    Whitcher, Ralph

    2007-01-01

    1 - Description of program or function: SACALC2B calculates the average solid angle subtended by a rectangular or circular detector window to a coaxial or non-coaxial rectangular, circular or point source, including where the source and detector planes are not parallel. SACALC C YL calculates the average solid angle subtended by a cylinder to a rectangular or circular source, plane or thick, at any location and orientation. This is needed, for example, in calculating the intrinsic gamma efficiency of a detector such as a GM tube. The program also calculates the number of hits on the cylinder side and on each end, and the average path length through the detector volume (assuming no scattering or absorption). Point sources can be modelled by using a circular source of zero radius. NEA-1688/03: Documentation has been updated (January 2006). 2 - Methods: The program uses a Monte Carlo method to calculate average solid angle for source-detector geometries that are difficult to analyse by analytical methods. The values of solid angle are calculated to accuracies of typically better than 0.1%. The calculated values from the Monte Carlo method agree closely with those produced by polygon approximation and numerical integration by Gardner and Verghese, and others. 3 - Restrictions on the complexity of the problem: The program models a circular or rectangular detector in planes that are not necessarily coaxial, nor parallel. Point sources can be modelled by using a circular source of zero radius. The sources are assumed to be uniformly distributed. NEA-1688/04: In SACALC C YL, to avoid rounding errors, differences less than 1 E-12 are assumed to be zero

  16. TRUST IN B2B E-MARKETPLACES

    Directory of Open Access Journals (Sweden)

    SEBASTIAN KOT

    2011-01-01

    Full Text Available The paper presents background of B2B exchanges and review of their forms and functionalities. The benefits and fails reasons are noticed. European enterprises interest in B2B trade is next aspect of consideration. Finally, the trust barriers of B2B exchanges are presented.

  17. Dietary sources of vitamin B-12 and their association with vitamin B-12 status markers in healthy older adults in the B-PROOF study

    NARCIS (Netherlands)

    Brouwer-Brolsma, E.M.; Dhonukshe-Rutten, R.A.M.; Wijngaarden, van J.P.; Zwaluw, van der N.L.; Velde, van der N.; Groot, de C.P.G.M.

    2015-01-01

    Low vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations between

  18. Dietary Sources of Vitamin B-12 and Their Association with Vitamin B-12 Status Markers in Healthy Older Adults in the B-PROOF Study

    NARCIS (Netherlands)

    Brouwer-Brolsma, Elske M.; Dhonukshe-Rutten, Rosalie A. M.; van Wijngaarden, Janneke P.; Zwaluw, Nikita L. van der; Velde, Nathalie van der; de Groot, Lisette C. P. G. M.

    2015-01-01

    Low vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations between

  19. Dietary sources of vitamin B-12 and their association with vitamin B-12 status markers in healthy older adults in the B-PROOF study

    NARCIS (Netherlands)

    E.M. Brouwer-Brolsma (Elske); R.A.M. Dhonukshe-Rutten (Rosalie); J.P. van Wijngaarden (Janneke); N.L. van der Zwaluw (N.); N. van der Velde (Nathalie); L.C.P.G.M. de Groot (Lisette)

    2015-01-01

    textabstractLow vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations

  20. 40 CFR Table 2b to Subpart Zzzz of... - Operating Limitations for New and Reconstructed 2SLB and Compression Ignition Stationary RICE...

    Science.gov (United States)

    2010-07-01

    ... Reconstructed 2SLB and Compression Ignition Stationary RICE >500 HP Located at a Major Source of HAP Emissions, Existing Non-Emergency Compression Ignition Stationary RICE >500 HP, and New and Reconstructed 4SLB Burn Stationary RICE â¥250 HP Located at a Major Source of HAP Emissions 2b Table 2b to Subpart ZZZZ of Part 63...

  1. Impact of information sources on the knowledge of adolescents about hepatitis B

    International Nuclear Information System (INIS)

    Thaver, A.M.; Kamal, A.

    2010-01-01

    Objective: To assess the impact of various sources of information on school going adolescents (belonging to higher social strata between ages 14-19 years) regarding Hepatitis B; its various types, importance, symptoms and cures. Methods: A self-administered survey was conducted among the secondary school students (9-12 grades) of a private school for this purpose. Results: A total of 160 students were approached from which 158 (98%) agreed to take part in the survey. Overall 98% students claimed to know something about Hepatitis B. But only 52% of all had comprehensive and correct knowledge about symptoms, causes and measures for prevention of Hepatitis B. Their major sources of knowledge were parents (57%) and television (56%) followed by newspapers and books (31%), doctors (30%) teachers and peers (29%). Conclusion: Only half of the adolescents had correct knowledge about Hepatitis B, which infers that an average person's level of knowledge would have many misperceptions and myths. Television and parents are the most influential sources of imparting health education to adolescents. Thus it is imperative that these sources of knowledge strengthened to provide correct information to adolescents. (author)

  2. Identification of SH2B2β as an Inhibitor for SH2B1- and SH2B2α-Promoted Janus Kinase-2 Activation and Insulin Signaling

    OpenAIRE

    Li, Minghua; Li, Zhiqin; Morris, David L.; Rui, Liangyou

    2007-01-01

    The SH2B family has three members (SH2B1, SH2B2, and SH2B3) that contain conserved dimerization (DD), pleckstrin homology, and SH2 domains. The DD domain mediates the formation of homo- and heterodimers between members of the SH2B family. The SH2 domain of SH2B1 (previously named SH2-B) or SH2B2 (previously named APS) binds to phosphorylated tyrosines in a variety of tyrosine kinases, including Janus kinase-2 (JAK2) and the insulin receptor, thereby promoting the activation of JAK2 or the ins...

  3. An Empirical Examination of Reverse Auction Appropriateness in B2B Source Selection

    National Research Council Canada - National Science Library

    Hawkins, Timothy G

    2006-01-01

    .... This study relies upon strategic sourcing concepts coupled with theories of competition, goal-setting, and leadership to develop a conceptual model of antecedents to appropriateness of e-RA usage...

  4. Possible detection of an emission feature near 584 A in the direction of G191-B2B

    Science.gov (United States)

    Green, James; Bowyer, Stuart; Jelinsky, Patrick

    1990-01-01

    A possible spectral emission feature is reported in the direction of the nearby hot white dwarf G191-B2B at 581.5 + or - 6 A with a significance of 3.8 sigma. This emission has been identified as He I 584.3 A. The emission cannot be due to local geocoronal emission or interplanetary backscatter of solar He I 584 A emission because the feature is not detected in a nearby sky exposure. Possible sources for this emission are examined, including the photosphere of G191-B2B, the comparison star G191-B2A, and a possible nebulosity near or around G191-B2B. The parameters required to explain the emission are derived for each case. All of these explanations require unexpected physical conditions; hence we believe this result must receive confirming verification despite the statistical likelihood of the detection.

  5. Possible detection of an emission feature near 584 A in the direction of G191-B2B

    International Nuclear Information System (INIS)

    Green, J.; Bowyer, S.; Jelinsky, P.

    1990-01-01

    A possible spectral emission feature is reported in the direction of the nearby hot white dwarf G191-B2B at 581.5 + or - 6 A with a significance of 3.8 sigma. This emission has been identified as He I 584.3 A. The emission cannot be due to local geocoronal emission or interplanetary backscatter of solar He I 584 A emission because the feature is not detected in a nearby sky exposure. Possible sources for this emission are examined, including the photosphere of G191-B2B, the comparison star G191-B2A, and a possible nebulosity near or around G191-B2B. The parameters required to explain the emission are derived for each case. All of these explanations require unexpected physical conditions; hence we believe this result must receive confirming verification despite the statistical likelihood of the detection. 15 refs

  6. ROSAT EUV and soft X-ray studies of atmospheric composition and structure in G191-B2B

    Science.gov (United States)

    Barstow, M. A.; Fleming, T. A.; Finley, D. S.; Koester, D.; Diamond, C. J.

    1993-01-01

    Previous studies of the hot DA white dwarf GI91-B2B have been unable to determine whether the observed soft X-ray and EUV opacity arises from a stratified hydrogen and helium atmosphere or from the presence of trace metals in the photosphere. New EUV and soft X-ray photometry of this star, made with the ROSAT observatory, when analyzed in conjunction with the earlier data, shows that the stratified models cannot account for the observed fluxes. Consequently, we conclude that trace metals must be a substantial source of opacity in the photosphere of G191-B2B.

  7. EVIDENCE FOR LOW BLACK HOLE SPIN AND PHYSICALLY MOTIVATED ACCRETION MODELS FROM MILLIMETER-VLBI OBSERVATIONS OF SAGITTARIUS A*

    Energy Technology Data Exchange (ETDEWEB)

    Broderick, Avery E [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Fish, Vincent L; Doeleman, Sheperd S [Massachusetts Institute of Technology, Haystack Observatory, Route 40, Westford, MA 01886 (United States); Loeb, Abraham [Institute for Theory and Computation, Harvard University, Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2011-07-10

    Millimeter very long baseline interferometry (mm-VLBI) provides the novel capacity to probe the emission region of a handful of supermassive black holes on sub-horizon scales. For Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, this provides access to the region in the immediate vicinity of the horizon. Broderick et al. have already shown that by leveraging spectral and polarization information as well as accretion theory, it is possible to extract accretion-model parameters (including black hole spin) from mm-VLBI experiments containing only a handful of telescopes. Here we repeat this analysis with the most recent mm-VLBI data, considering a class of aligned, radiatively inefficient accretion flow (RIAF) models. We find that the combined data set rules out symmetric models for Sgr A*'s flux distribution at the 3.9{sigma} level, strongly favoring length-to-width ratios of roughly 2.4:1. More importantly, we find that physically motivated accretion flow models provide a significantly better fit to the mm-VLBI observations than phenomenological models, at the 2.9{sigma} level. This implies that not only is mm-VLBI presently capable of distinguishing between potential physical models for Sgr A*'s emission, but further that it is sensitive to the strong gravitational lensing associated with the propagation of photons near the black hole. Based upon this analysis we find that the most probable magnitude, viewing angle, and position angle for the black hole spin are a = 0.0{sup +0.64+0.86}, {theta}=68{sup o+5o+9o}{sub -20}{sup o}{sub -28}{sup o}, and {xi}=-52{sup o+17o+33o}{sub -15}{sup o}{sub -24}{sup o} east of north, where the errors quoted are the 1{sigma} and 2{sigma} uncertainties.

  8. EVIDENCE FOR LOW BLACK HOLE SPIN AND PHYSICALLY MOTIVATED ACCRETION MODELS FROM MILLIMETER-VLBI OBSERVATIONS OF SAGITTARIUS A*

    International Nuclear Information System (INIS)

    Broderick, Avery E.; Fish, Vincent L.; Doeleman, Sheperd S.; Loeb, Abraham

    2011-01-01

    Millimeter very long baseline interferometry (mm-VLBI) provides the novel capacity to probe the emission region of a handful of supermassive black holes on sub-horizon scales. For Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, this provides access to the region in the immediate vicinity of the horizon. Broderick et al. have already shown that by leveraging spectral and polarization information as well as accretion theory, it is possible to extract accretion-model parameters (including black hole spin) from mm-VLBI experiments containing only a handful of telescopes. Here we repeat this analysis with the most recent mm-VLBI data, considering a class of aligned, radiatively inefficient accretion flow (RIAF) models. We find that the combined data set rules out symmetric models for Sgr A*'s flux distribution at the 3.9σ level, strongly favoring length-to-width ratios of roughly 2.4:1. More importantly, we find that physically motivated accretion flow models provide a significantly better fit to the mm-VLBI observations than phenomenological models, at the 2.9σ level. This implies that not only is mm-VLBI presently capable of distinguishing between potential physical models for Sgr A*'s emission, but further that it is sensitive to the strong gravitational lensing associated with the propagation of photons near the black hole. Based upon this analysis we find that the most probable magnitude, viewing angle, and position angle for the black hole spin are a = 0.0 +0.64+0.86 , θ=68 o+5 o +9 o -20 o -28 o , and ξ=-52 o+17 o +33 o -15 o -24 o east of north, where the errors quoted are the 1σ and 2σ uncertainties.

  9. Ultrahigh B doping (≤1022 cm-3) during Si(001) gas-source molecular-beam epitaxy: B incorporation, electrical activation, and hole transport

    International Nuclear Information System (INIS)

    Glass, G.; Kim, H.; Desjardins, P.; Taylor, N.; Spila, T.; Lu, Q.; Greene, J. E.

    2000-01-01

    Si(001) layers doped with B concentrations C B between 1x10 17 and 1.2x10 22 cm -3 (24 at %) were grown on Si(001)2x1 at temperatures T s =500-850 degree sign C by gas-source molecular-beam epitaxy from Si 2 H 6 and B 2 H 6 . C B increases linearly with the incident precursor flux ratio J B 2 H 6 /J Si 2 H 6 and B is incorporated into substitutional electrically active sites at concentrations up to C B * (T s ) which, for T s =600 degree sign C, is 2.5x10 20 cm -3 . At higher B concentrations, C B increases faster than J B 2 H 6 /J Si 2 H 6 and there is a large and discontinuous decrease in the activated fraction of incorporated B. However, the total activated B concentration continues to increase and reaches a value of N B =1.3x10 21 cm -3 with C B =1.2x10 22 cm -3 . High-resolution x-ray diffraction (HR-XRD) and reciprocal space mapping measurements show that all films, irrespective of C B and T s , are fully strained. No B precipitates or misfit dislocations were detected by HR-XRD or transmission electron microscopy. The lattice constant in the film growth direction a (perpendicular sign) decreases linearly with increasing C B up to the limit of full electrical activation and continues to decrease, but nonlinearly, with C B >C B * . Room-temperature resistivity and conductivity mobility values are in good agreement with theoretical values for B concentrations up to C B =2.5x10 20 and 2x10 21 cm -3 , respectively. All results can be explained on the basis of a model which accounts for strong B surface segregation to the second-layer with a saturation coverage θ B,sat of 0.5 ML (corresponding to C B =C B * ). At higher C B (i.e., θ BB,sat ), B accumulates in the upper layer as shown by thermally programmed desorption measurements, and a parallel incorporation channel becomes available in which B is incorporated into substitutional sites as B pairs that are electrically inactive but have a low charge-scattering cross section. (c) 2000 The American Physical

  10. B2B oriented on-line applications generator

    OpenAIRE

    Vintilă Bogdan-Cătălin

    2008-01-01

    B2B applications are presented. Quality characteristics of B2B applications are defined. B2B application structure is defined. The application for contracts is developed. The advantages are identified.

  11. Digitaalisen markkinoinnin suunnitelma b2b-yritykselle

    OpenAIRE

    Harhakoski, Oskari

    2011-01-01

    Työ käsittelee digitaalisen markkinoinnin suunnitelman tekemistä b2b-yritykselle. Tavoitteena oli kilpailuedun hankkiminen sosiaalisen median tehokkaalla hyödyntämisellä mark-kinoinnissa. Konkreettisemmin yritys halusi lisää näkyvyyttä ja myyntiä. Suunnitelman laatimisessa hyödynnettiin POST-menetelmää. Erityistä huomiota kiinnitettiin b2b-markkinoinnin eroihin b2c-markkinointiin verrattuna. Myös yrityksen toimiminen Suomen markkinoilla huomioitiin. Lisäksi analysoitiin kilpailijoita asia...

  12. Assessed Clean Water Act 305(b) Water Sources of Impairment

    Data.gov (United States)

    U.S. Environmental Protection Agency — Identifies the sources of impairment for assessed waters under the Clean Water Act 305(b) program. This view can be used for viewing the details at the assessment...

  13. Bu-2470, a new peptide antibiotic complex. II. Structure determination of Bu-2470 A, B1, B2a and B2b.

    Science.gov (United States)

    Sugawara, K; Yonemoto, T; Konishi, M; Matsumoto, K; Miyaki, T; Kawaguchi, H

    1983-06-01

    The structures of Bu-2470 A, B1, B2a, and B2b have been determined. Bu-2470 A is a simple octapeptide having no fatty acid moiety, while Bu-2470 B1, B2a and B2b are octapeptides that have been acylated with a beta-hydroxy C11 or C10 fatty acid. The octapeptide structure of Bu-2470 components was found identical with that of octapeptin C1, hence generic names of octapeptin C0, C2, C3 and C4 are proposed for Bu-2470 A, B1, B2a and B2b, respectively.

  14. Improving magnetic properties of MgB_2 bulk superconductors by synthetic engine oil treatment

    International Nuclear Information System (INIS)

    Taylan Koparan, E.; Savaskan, B.; Yanmaz, E.

    2016-01-01

    Highlights: • The effects of synthetic engine oil treatment on magnetic properties of bulk MgB_2 superconductors has been first time investigated and reported. • Synthetic engine oil used as a product which is cheap and a rich carbon source obviously has improved the superconducting magnetic properties of MgB_2. • The critical current density of all of MgB_2 samples immersed at different standby time in engine oil in whole field range has been better than that of the pure MgB_2 sample. • The MgB_2 sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. - Abstract: The present study focuses on the effects of standby time of the MgB_2 samples immersed in synthetic engine oil on the critical current density ( J_c(H)), magnetic field dependence of the pinning force density f_p(b) and T_c performances of MgB_2 bulk superconductors. Synthetic engine oil was used as a product which is cheap and a rich carbon source. Manufactured MgB_2 pellet samples were immersed at different standby time of 30 min, 120 min, 300 min and 1440 min in synthetic engine oil after the first heating process. Finally, MgB_2 samples immersed in synthetic engine oil were sintered at 1000 °C and kept for 15 min in Ar atmosphere. The critical current density of all of MgB_2 samples immersed at different standby time in engine oil in whole field range was better than that of the pure MgB_2 sample because of the number of the pinning centers. The MgB_2 sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. The J_c value for the pure sample is 2.0 × 10"3 A/cm"2, whereas for the MgB_2 sample immersed at 300 min standby time in engine oil the J_c is enhanced to 4.8 × 10"3 A/cm"2 at 5 K and 3 T. The superconducting transition temperature (T_c) did not change with the increasing standby time of the samples in synthetic engine oil at all. The best diamagnetic property was

  15. E-Business Models in B2B: Process Based Categorization and Analysis of B2B Models

    OpenAIRE

    Mahesh S. Raisinghani; Turan Melemez; Lijie Zou; Chris Paslowski; Irma Kimvidze; Susanne Taha; Klaus Simons

    2005-01-01

    The business models in business-to-business (B2B) e-commerce and their effectiveness have been a major topic of research in recent years. Due to the variety of existing models, it seems difficult to find a widely accepted categorization that can be analyzed and assessed. An in-depth study that provides a process-based approach to B2B e-commerce is presented and illustrated with examples from industry. A comparative examination of both the buy and the sell side based on a process-related appro...

  16. A TWO MICRON ALL SKY SURVEY VIEW OF THE SAGITTARIUS DWARF GALAXY. VI. s-PROCESS AND TITANIUM ABUNDANCE VARIATIONS ALONG THE SAGITTARIUS STREAM

    International Nuclear Information System (INIS)

    Chou, Mei-Yin; Majewski, Steven R.; Patterson, Richard J.; Cunha, Katia; Smith, Verne V.; Martinez-Delgado, David; Geisler, Doug

    2010-01-01

    We present high-resolution spectroscopic measurements of the abundances of the α element titanium (Ti) and s-process elements yttrium (Y) and lanthanum (La) for 59 candidate M giant members of the Sagittarius (Sgr) dwarf spheroidal (dSph) + tidal tail system pre-selected on the basis of position and radial velocity (RV). As expected, the majority of these stars show peculiar abundance patterns compared to those of nominal Milky Way (MW) stars, but as a group, the stars form a coherent picture of chemical enrichment of the Sgr dSph from [Fe/H] = -1.4 to solar abundance. This sample of spectra provides the largest number of Ti, La, and Y abundances yet measured for a dSph, and spans metallicities not typically probed by studies of the other, generally more metal-poor MW satellites. On the other hand, the overall [Ti/Fe], [Y/Fe], [La/Fe], and [La/Y] patterns with [Fe/H] of the Sgr stream plus Sgr core do, for the most part, resemble those seen in the Large Magellanic Cloud (LMC) and other dSphs, only shifted by Δ[Fe/H] ∼ +0.4 from the LMC and by ∼+1 dex from the other dSphs; these relative shifts reflect the faster and/or more efficient chemical evolution of Sgr compared to the other satellites, and show that Sgr has had an enrichment history more like the LMC than the other dSphs. By tracking the evolution of the abundance patterns along the Sgr stream we can follow the time variation of the chemical make-up of dSph stars donated to the Galactic halo by Sgr. This evolution demonstrates that while the bulk of the stars currently in the Sgr dSph is quite unlike those of the Galactic halo, an increasing number of stars farther along the Sgr stream have abundances like MW halo stars, a trend that shows clearly how the Galactic halo could have been contributed by present-day satellite galaxies even if the present chemistry of those satellites is now different from typical halo field stars. Finally, we analyze the chemical abundances of a moving group of M giants

  17. Insights into CYP2B6-mediated drug–drug interactions

    Directory of Open Access Journals (Sweden)

    William D. Hedrich

    2016-09-01

    Full Text Available Mounting evidence demonstrates that CYP2B6 plays a much larger role in human drug metabolism than was previously believed. The discovery of multiple important substrates of CYP2B6 as well as polymorphic differences has sparked increasing interest in the genetic and xenobiotic factors contributing to the expression and function of the enzyme. The expression of CYP2B6 is regulated primarily by the xenobiotic receptors constitutive androstane receptor (CAR and pregnane X receptor (PXR in the liver. In addition to CYP2B6, these receptors also mediate the inductive expression of CYP3A4, and a number of important phase II enzymes and drug transporters. CYP2B6 has been demonstrated to play a role in the metabolism of 2%–10% of clinically used drugs including widely used antineoplastic agents cyclophosphamide and ifosfamide, anesthetics propofol and ketamine, synthetic opioids pethidine and methadone, and the antiretrovirals nevirapine and efavirenz, among others. Significant inter-individual variability in the expression and function of the human CYP2B6 gene exists and can result in altered clinical outcomes in patients receiving treatment with CYP2B6-substrate drugs. These variances arise from a number of sources including genetic polymorphism, and xenobiotic intervention. In this review, we will provide an overview of the key players in CYP2B6 expression and function and highlight recent advances made in assessing clinical ramifications of important CYP2B6-mediated drug–drug interactions.

  18. Hydrothermal synthesis of B-doped Bi2MoO6 and its high photocatalytic performance for the degradation of Rhodamine B

    Science.gov (United States)

    Wang, Min; Han, Jin; Guo, Pengyao; Sun, Mingzhi; Zhang, Yu; Tong, Zhu; You, Meiyan; Lv, Chunmei

    2018-02-01

    B-doped Bi2MoO6 photocatalysts have been synthesized by a hydrothermal method using HBO3 as the doping source and the effect of B doping content on Bi2MoO6 structure and performance was studied. The samples were characterized with XPS, XRD, SEM, BET, UV-Vis DRS, and PL. The photocatalytic activity was evaluated by photocatalytic degradation of Rhodamine B (RhB) under visible light (λ ≥ 420 nm). The results show that all samples are orthorhombic structure. Doping Bi2MoO6 with B increases the amount of Bi5+ and oxygen vacancies, which led to stronger absorption in visible light region and lower band gap energy of the B-doped Bi2MoO6 but had little impact on morphology. B doping significantly improves the photocatalytic activity of Bi2MoO6 and the highest photocatalytic degradation rate is 89% when the initial molar ratio of B to Bi is 0.01.

  19. Vitamin B2, vitamin B12 and total homocysteine status in children and their associations with dietary intake of B-vitamins from different food groups: the Healthy Growth Study.

    Science.gov (United States)

    Manios, Yannis; Moschonis, George; Dekkers, Renske; Mavrogianni, Christina; Grammatikaki, Eva; van den Heuvel, Ellen

    2017-02-01

    To examine the associations between the dietary intakes of certain B-vitamins from different food sources with the relevant plasma status indices in children. A representative subsample of 600 children aged 9-13 years from the Healthy Growth Study was selected. Dietary intakes of vitamins B 2 , B 12 , B 6 and folate derived from different food sources were estimated. Plasma levels of vitamin B 2 (or riboflavin), methylmalonic acid (MMA) and total homocysteine (tHcy) were also measured. Plasma concentrations of vitamin B 2 below 3 μg/L were found in 22.8 % of the children. Children in the lower quartile of dietary vitamin B 2 intake were found to have the lowest plasma vitamin B 2 levels compared to children in the upper three quartiles (5.06 ± 7.63 vs. 6.48 ± 7.88, 6.34 ± 7.63 and 6.05 ± 4.94 μg/L respectively; P = 0.003). Regarding vitamin B 12 children in the lower quartile of dietary intake had higher mean plasma tHcy levels compared to children in the upper two quartiles, respectively (6.00 ± 1.79 vs. 5.41 ± 1.43 and 5.46 ± 1.64 μmol/L; P = 0.012). Positive linear associations were observed between plasma vitamin B 2 levels and dietary vitamin B 2 derived from milk and fruits (β = 0.133; P = 0.001 and β = 0.086; P = 0.037). Additionally, nonlinear associations were also observed between plasma vitamin B 2 levels and vitamin B 2 derived from red meat, as well as between tHcy levels and vitamins B 12 and B 6 derived from milk; vitamins B 12 , B 6 and folate derived from cereal products and folate derived from fruits. A considerably high prevalence of poor plasma vitamin B 2 status was observed in children. The intake of milk, fruits and cereals was associated with more favorable tHcy levels, while the intake of milk and fruits with more favorable plasma B2 levels. However, these findings need to be further confirmed from controlled dietary intervention studies examining the modulation of biomarkers of B-vitamins.

  20. Bismuth-boron multiple bonding in BiB_2O"- and Bi_2B"-

    International Nuclear Information System (INIS)

    Jian, Tian; Cheung, Ling Fung; Chen, Teng-Teng; Wang, Lai-Sheng

    2017-01-01

    Despite its electron deficiency, boron is versatile in forming multiple bonds. Transition-metal-boron double bonding is known, but boron-metal triple bonds have been elusive. Two bismuth boron cluster anions, BiB_2O"- and Bi_2B"-, containing triple and double B-Bi bonds are presented. The BiB_2O"- and Bi_2B"- clusters are produced by laser vaporization of a mixed B/Bi target and characterized by photoelectron spectroscopy and ab initio calculations. Well-resolved photoelectron spectra are obtained and interpreted with the help of ab initio calculations, which show that both species are linear. Chemical bonding analyses reveal that Bi forms triple and double bonds with boron in BiB_2O"- ([Bi≡B-B≡O]"-) and Bi_2B"- ([Bi=B=Bi]"-), respectively. The Bi-B double and triple bond strengths are calculated to be 3.21 and 4.70 eV, respectively. This is the first experimental observation of Bi-B double and triple bonds, opening the door to design main-group metal-boron complexes with multiple bonding. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. B2-B2.5 code benchmarking

    Energy Technology Data Exchange (ETDEWEB)

    Dekeyser, W.; Baelmans, M; Voskoboynikov, S.; Rozhansky, V.; Reiter, D.; Wiesen, S.; Kotov, V.; Boerner, P.

    2011-01-15

    ITER-IO currently (and since about 15 years) employs the SOLPS4.xxx code for its divertor design, currently version SOLPS4.3. SOLPS.xxx is a special variant of the B2-EIRENE code, which was originally developed by an European consortium (FZ Juelich, AEA Culham, ERM Belgium/KU Leuven) in the late eighties and early nineties of the last century under NET contracts. Until today even the very similar edge plasma codes within the SOLPS family, if run on a seemingly identical choice of physical parameters, still sometimes disagree significantly with each other. It is obvious that in computational engineering applications, as they are carried out for the various ITER divertor aspects with SOLPS4.3 for more than a decade now, any transition from one to another code must be fully backward compatible, or, at least, the origin of differences in the results must be identified and fully understood quantitatively. In this report we document efforts undertaken in 2010 to ultimately eliminate the third issue. For the kinetic EIRENE part within SOLPS this backward compatibility (back until 1996) was basically achieved (V. Kotov, 2004-2006) and SOLPS4.3 is now essentially up to date with the current EIRENE master maintained at FZ Juelich. In order to achieve a similar level of reproducibility for the plasma fluid (B2, B2.5) part, we follow a similar strategy, which is quite distinct from the previous SOLPS benchmark attempts: the codes are ''disintegrated'' and pieces of it are run on smallest (i.e. simplest) problems. Only after full quantitative understanding is achieved, the code model is enlarged, integrated, piece by piece again, until, hopefully, a fully backward compatible B2 / B2.5 ITER edge plasma simulation will be achieved. The status of this code dis-integration effort and its findings until now (Nov. 2010) are documented in the present technical note. This work was initiated in a small workshop by the three partner teams of KU Leuven, St. Petersburg

  2. Directional crystallization of B4C-NbB2 and B4C-MoB2 eutectic compositions

    International Nuclear Information System (INIS)

    Paderno, Varvara; Paderno, Y.B.; Filippov, Vladimir; Liashchenko, Alfred

    2004-01-01

    We studied the directional crystallization of different compositions in B 4 C-NbB 2 and B 4 C-MoB 2 systems. The eutectic compositions for both systems are evaluated. It is shown that in the first system the rod-like eutectic structure is formed, in second, the 'Chinese hieroglyphics'. In both cases high hardness and high microplasticity are observed, which are much more than for individual component phases. These compositions may be considered as a new kind of self-strengthening composite materials

  3. Il B2B e il paradigma dei costi di transazione (B2B and the Transaction Costs Paradigm

    Directory of Open Access Journals (Sweden)

    Pierluigi Sabbatini

    2001-06-01

    Full Text Available Business to Business (B2B Internet commerce causes a significant contraction of transaction costs. According to the Coase paradigm, we would thus expect a deverticalization of the industry and broader scope for anonymous market mechanisms. In reality, such expectations are not fully borne out by the facts. When the industrial structure is concentrated the B2Bgenerally loses its independence, and is owned by the firms which most contribute to its development, e.g. the ones able to bring the liquidity to it. The B2B governance mechanism established by these firms gives hierarchical mechanisms a role which they do not usually play in extensive, anonymous markets.

  4. B2B-myynnin nykytila ja haasteet Suomessa

    OpenAIRE

    Ylimaula, Jukka

    2014-01-01

    Tämä opinnäytetyö tutki B2B-myynnin nykytilaa valituissa suomalaisissa yrityksissä. Tutkimuksen tavoite oli selvittää myyntijohdon mielestä B2B-myynnissä tärkeitä asioita ja hahmottaa tapaa, jolla organisaatio toimii yhteistyössä myynnissä. Näin teemojen pohjalta opinnäytetyö pyrki muodostamaan ajankuvan suomalaisesta B2B-myynnistä. Opinnäytetyö muodostuu teoriaosasta ja empiirisestä osasta. Teoreettinen osuus tutkii myyntiä sekä myyjän että ostajan näkökulmasta. Myös asiakassuhteita ja m...

  5. Hotelzon's B2B content marketing plan

    OpenAIRE

    Nguyen, Trang

    2015-01-01

    This thesis follows a research-based structure. The objective of this research was to help the case company Hotelzon develop a practical business-to-business (B2B) content marketing plan to engage new customers. The research topic came up when the case company named Hotelzon started expanding its business to many other countries. Therefore, attracting new prospects has become a critical issue to B2B corporates in this online world and constantly changing business environment. The first pa...

  6. A Model of B2B Exchanges

    OpenAIRE

    Gabor Fath; Miklos Sarvary

    2001-01-01

    B2B exchanges are revolutionizing the way businesses will buy and sell a variety of intermediary products and services. It is estimated that most of the roughly $7 trillion worth of business transactions are likely to go through these new institutions within the next decade. This paper tries to understand the economics governing the transactions within B2B exchanges and analyze their likely evolution over time. In doing so, we start by providing the rigorous definitions to a number of critica...

  7. ORM-based semantics of B2B transactions.

    NARCIS (Netherlands)

    Balsters, H.; van Blommestein, F.; Meersman, R; Herrero, P; Dillon, T

    2009-01-01

    After widespread implementation of Enterprise Resource Planning and Personal Information Management, the next wave in the application of ICT is headed towards business to business (B2B) communication. B2B has a number of specific aspects, one of them being negotiation. This aspect has been largely

  8. Dietary intake of the water-soluble vitamins B1, B2, B6, B12 and C in 10 countries in the European Prospective Investigation into Cancer and Nutrition.

    Science.gov (United States)

    Olsen, A; Halkjaer, J; van Gils, C H; Buijsse, B; Verhagen, H; Jenab, M; Boutron-Ruault, M C; Ericson, U; Ocké, M C; Peeters, P H M; Touvier, M; Niravong, M; Waaseth, M; Skeie, G; Khaw, K T; Travis, R; Ferrari, P; Sanchez, M J; Agudo, A; Overvad, K; Linseisen, J; Weikert, C; Sacerdote, C; Evangelista, A; Zylis, D; Tsiotas, K; Manjer, J; van Guelpen, B; Riboli, E; Slimani, N; Bingham, S

    2009-11-01

    To describe the intake of vitamins thiamine (B1), riboflavin (B2), B6 (pyridoxine), B12 (cobalamine) and C (ascorbic acid) and their food sources among 27 centres in 10 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Between 1995 and 2000, 36 034 persons aged between 35 and 74 years were administered a standardized 24-h dietary recall using a computerized interview software programme (EPIC-SOFT). Intakes of the four B vitamins and vitamin C were estimated using the standardized EPIC Nutrient Database (ENDB). Mean intakes were adjusted for age and weighted by season and day of recall. Intake of B vitamins did not vary considerably between centres, except in the UK health-conscious cohort, in which substantially higher intakes of thiamine and lower intakes of vitamin B12 were reported compared with other centres. Overall, meat was the most important contributor to the B vitamins in all centres except in the UK health-conscious group. Vitamin C showed a clear geographical gradient, with higher intakes in the southern centres as compared with the northern ones; this was more pronounced in men than in women. Vegetables and fruits were major contributors to vitamin C in all centres, but juices and potatoes were also important sources in the northern centres. This study showed no major differences across centres in the mean intakes of B vitamins (thiamine, riboflavin, B6, B12), whereas a tendency towards a north-south gradient was observed for vitamin C.

  9. The Chandra Source Catalog 2.0: Estimating Source Fluxes

    Science.gov (United States)

    Primini, Francis Anthony; Allen, Christopher E.; Miller, Joseph; Anderson, Craig S.; Budynkiewicz, Jamie A.; Burke, Douglas; Chen, Judy C.; Civano, Francesca Maria; D'Abrusco, Raffaele; Doe, Stephen M.; Evans, Ian N.; Evans, Janet D.; Fabbiano, Giuseppina; Gibbs, Danny G., II; Glotfelty, Kenny J.; Graessle, Dale E.; Grier, John D.; Hain, Roger; Hall, Diane M.; Harbo, Peter N.; Houck, John C.; Lauer, Jennifer L.; Laurino, Omar; Lee, Nicholas P.; Martínez-Galarza, Juan Rafael; McCollough, Michael L.; McDowell, Jonathan C.; McLaughlin, Warren; Morgan, Douglas L.; Mossman, Amy E.; Nguyen, Dan T.; Nichols, Joy S.; Nowak, Michael A.; Paxson, Charles; Plummer, David A.; Rots, Arnold H.; Siemiginowska, Aneta; Sundheim, Beth A.; Tibbetts, Michael; Van Stone, David W.; Zografou, Panagoula

    2018-01-01

    The Second Chandra Source Catalog (CSC2.0) will provide information on approximately 316,000 point or compact extended x-ray sources, derived from over 10,000 ACIS and HRC-I imaging observations available in the public archive at the end of 2014. As in the previous catalog release (CSC1.1), fluxes for these sources will be determined separately from source detection, using a Bayesian formalism that accounts for background, spatial resolution effects, and contamination from nearby sources. However, the CSC2.0 procedure differs from that used in CSC1.1 in three important aspects. First, for sources in crowded regions in which photometric apertures overlap, fluxes are determined jointly, using an extension of the CSC1.1 algorithm, as discussed in Primini & Kashyap (2014ApJ...796…24P). Second, an MCMC procedure is used to estimate marginalized posterior probability distributions for source fluxes. Finally, for sources observed in multiple observations, a Bayesian Blocks algorithm (Scargle, et al. 2013ApJ...764..167S) is used to group observations into blocks of constant source flux.In this poster we present details of the CSC2.0 photometry algorithms and illustrate their performance in actual CSC2.0 datasets.This work has been supported by NASA under contract NAS 8-03060 to the Smithsonian Astrophysical Observatory for operation of the Chandra X-ray Center.

  10. Nanostructure characterization of Ni and B layers as artificial pinning centers in multilayered MgB2/Ni and MgB2/B superconducting thin films

    International Nuclear Information System (INIS)

    Sosiati, H.; Hata, S.; Doi, T.; Matsumoto, A.; Kitaguchi, H.; Nakashima, H.

    2013-01-01

    Highlights: ► Nanostructure characterization of Ni and B layers as artificial pinning centers (APCs). ► Relationship between nanostructure and J c property. ► Enhanced J c in parallel field by parallel APCs within the MgB 2 film. -- Abstract: Research on the MgB 2 /Ni and MgB 2 /B multilayer films fabricated by an electron beam (EB) evaporation technique have been extensively carried out. The critical current density, J c of MgB 2 /Ni and MgB 2 /B multilayer films in parallel fields has been suggested to be higher than that of monolayer MgB 2 film due to introducing the artificial pinning centers of nano-sized Ni and B layers. Nanostructure characterization of the artificial pinning centers in the multilayer films were examined by transmission electron microscopy (TEM) and scanning TEM (STEM-energy dispersive X-ray spectroscopy (STEM-EDS))–EDS to understand the mechanism of flux pinning. The growth of columnar MgB 2 grains along the film-thickness direction was recognized in the MgB 2 /Ni multilayer film, but not in the MgB 2 /B multilayer film. Nano-sized Ni layers were present as crystalline epitaxial layers which is interpreted that Ni atoms might be incorporated into the MgB 2 lattice to form (Mg,Ni)B 2 phase. On the other hand, nano-sized B layers were amorphous layers. Crystalline (Mg,Ni)B 2 layers worked more effectively than amorphous B-layers, providing higher flux-pinning force that resulted in higher J c of the MgB 2 /Ni multilayer film than the MgB 2 /B multilayer film

  11. Effect of TiB2 Pretreatment on Pt/TiB2 Catalyst Performance

    International Nuclear Information System (INIS)

    Huang, Zhen; Lin, Rui; Fan, Renjie; Fan, Qinbai; Ma, Jianxin

    2014-01-01

    Highlights: • We pretreated Titanium diboride by different acids and alkali. • We synthesis the Pt/as-pretreated TiB 2 catalysts by a colloid route. • We investigated the effects of TiB 2 Pretreatment on Pt/TiB 2 Catalyst Performance. • The BET surface area and defects on the surface have a close relationship with the deposition of Pt nanoparticles. - Abstract: Carbon support corrosion of traditional Pt/C catalyst is one of the major contributors causing poor durability of proton exchange membrane fuel cells (PEMFC). Titanium diboride (TiB 2 ) has high electrical conductivity and considerable chemical stability, which making it as a good candidate for catalyst support in PEMFC. In this work, TiB 2 was pretreated by different acid and alkali. The as-obtained samples were characterized by Ex-situ microscopy (ESM) and X-ray diffraction (XRD). The pore size distribution (PSD) was analyzed by using DFT method. The PSD shows distinct volume in mesopore regions (less than 50 nm). The TiB2 pretreated by H 2 O 2 shows the biggest BET surface area of 57 m 2 g −1 and its PSD focus on mesoporous (1.5-8 nm) region, which resulted to high dispersion and better loading of Pt particles. The Hydrogen oxidization reaction (HOR) and oxygen reduction reaction (ORR) activity was characterized by Rotating Disk Electrode (RDE). The Pt/TiB 2 prepared by H 2 O 2 -pretreated TiB 2 using the colloidal method showed better half-cell electrochemical performance. Facile synthetic for the development of Pt/TiB 2 catalysts was developed

  12. Effects of dietary nitrogen levels and carbohydrate sources on apparent ruminal synthesis of some B vitamins in dairy cows.

    Science.gov (United States)

    Beaudet, V; Gervais, R; Graulet, B; Nozière, P; Doreau, M; Fanchone, A; Castagnino, D D S; Girard, C L

    2016-04-01

    Effects of nitrogen level and carbohydrate source on apparent ruminal synthesis (ARS) of thiamin, riboflavin, niacin, vitamin B6, folates, and vitamin B12 were evaluated using 4 lactating Holstein cows distributed in a 4 × 4 Latin square design with treatments following a 2 × 2 factorial arrangement. Cows were fitted with cannulas in the rumen and proximal duodenum. The treatments were 2 N levels and 2 carbohydrate sources. The diet with the high N level provided 14% crude protein, calculated to meet 110% of the protein requirements and an adequate supply in rumen-degradable protein, whereas the diet with the low N level contained 11% crude protein, calculated to meet 80% of the protein requirements with a shortage in rumen-degradable protein. Carbohydrate source treatments differed by their nature (i.e., high in starch from barley, corn, and wheat, or high in fiber from soybean hulls and dehydrated beet pulp). All 4 diets were isoenergetic, based on corn silage, and had the same forage-to-concentrate ratio (60:40, dry matter basis). Duodenal flow was determined using YbCl3 as a marker. Each B-vitamin ARS was calculated as duodenal flow minus daily intake. The intake of several B vitamins varied among treatments, but because the animals consumed a similar amount of feed every day (average of 20 kg of dry matter/d) the difference was mostly due to vitamin content of each ingredient and their relative proportion in the diets. Decreasing N concentration in the diet reduced vitamin B6 duodenal flow and increased its apparent ruminal degradation. It also decreased duodenal flow and ARS of folates. The high-starch diets increased duodenal flow and ruminal balance of riboflavin, vitamin B6, and folates, whereas the high-fiber diets increased vitamin B12 ARS and duodenal flow. These effects on apparent synthesis are possibly due to changes in ruminal fermentation. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  13. B2B-myyntiprosessi : case: Yritys X

    OpenAIRE

    Lamppu, Samuli

    2017-01-01

    Opinnäytetyön aiheena on B2B-myyntiprosessi yrityksessä x. Työn tavoitteena on kartoittaa yrityksen B2B-myyntiprosessin nykytila, tunnistaa mahdolliset ongelma-alueet ja tehdä tämän perusteella ehdotukset toimenpiteistä prosessin parantamiseksi. Työ tehdään suomalaisen PK-yrityksen toimeksiannosta. Opinnäytetyön taustalla on oma urani yrityksen yritysmyynnissä, ja työni kautta tunnistamani haasteet sekä mahdollisuudet, joita hyödyntämällä yritys voisi kehittää myyntitoimintaansa. Yritykse...

  14. On the nature of the galactic 2CG γ-ray sources

    International Nuclear Information System (INIS)

    Buccheri, R.; Morini, M.; Sacco, B.

    1981-01-01

    The identification of two γ-ray sources of the COS-B catalogue with radio pulsars is used as an important hint for the identification of the rest of the population. The relevant distributions of γ-ray pulsars visible at the Sun within the limiting sensitivity of COS-B are derived on the following assumptions: (i) the γ-ray luminosity is a decreasing power law of the pulsar age, as indicated by current models; (ii) the scale height of pulsars at creation is equal to that of the supernova remnants; (iii) the pulsars' birth rate and spatial distribution are those published by Taylor and Manchester (1977). As a preliminary result it is shown that 10 to 20 γ-ray pulsars may be visible from the Earth with distributional parameters not distinguishable from those of the 2CG γ-ray sources. It is suggested therefore that a significant fraction of the unidentified galactic γ-ray sources are pulsars. (author)

  15. The second COS-B catalogue of high-energy γ-ray sources

    International Nuclear Information System (INIS)

    Hermsen, W.

    1981-01-01

    Gamma-ray emission is produced in many localized regions. 13 high energy gamma-ray sources have previously been detected but because of difficulties of identification the nature of these sources is not clear. Further data from COS-B has been accumulated and allow a more systematic search for gamma-ray sources in the Galaxy. The 32 observations used were made between August 1975 and December 1978. Only events above 100 MeV have been included. The positions of the 25 detected gamma-ray sources are given. Only four sources of the catalogue have been identified, two with the Crab and Vela pulsars, one with 3C273 and one with the rho-Oph cloud complex. For the remainder, all but one of which lie close to the galactic disc, no unambiguous counterparts appear to exist at other wavelengths. (U.K.)

  16. Applying conceptual design to B2B sales negotiations

    DEFF Research Database (Denmark)

    Illi, Mikko; Ylirisku, Salu

    This paper addresses the challenge of perceiving B2B sales negotiation in a manner that would open up new possibilities for the improvement of the practice. B2B sales agents work under high pressure in developing relevant and appealing proposals when negotiating for a deal with a customer. The key...... problem that will be addressed is the building of understanding of a customer’s current needs and requirements, and then trying to devise an appropriate proposal to match these. The work of the sales agents in B2B sales negotiations is highly complex, as they need to understand both the modular machinery...... on the ways in which design sense making artefacts may drive also B2B sales agents’ work....

  17. B1 Cell IgE Impedes Mast Cell-Mediated Enhancement of Parasite Expulsion through B2 IgE Blockade

    Directory of Open Access Journals (Sweden)

    Rebecca K. Martin

    2018-02-01

    Full Text Available Helminth infection is known for generating large amounts of poly-specific IgE. Here we demonstrate that innate-like B1 cells are responsible for this IgE production during infection with the nematode parasites Nippostrongylus brasiliensis and Heligmosomoides polygyrus bakeri. In vitro analysis of B1 cell immunoglobulin class switch recombination to IgE demonstrated a requirement for anti-CD40 and IL-4 that was further enhanced when IL-5 was added or when the B1 source was helminth infected mice. An IL-25-induced upregulation of IgE in B1 cells was also demonstrated. In T cell-reconstituted RAG1−/− mice, N. brasiliensis clearance was enhanced with the addition of B2 cells in an IgE-dependent manner. This enhanced clearance was impeded by reconstitution with IgE sufficient B1 cells. Mucosal mast cells mediated the B2 cell enhancement of clearance in the absence of B1 cells. The data support B1 cell IgE secretion as a regulatory response exploited by the helminth.

  18. Doping-Induced Isotopic Mg11B2 Bulk Superconductor for Fusion Application

    Directory of Open Access Journals (Sweden)

    Qi Cai

    2017-03-01

    Full Text Available Superconducting wires are widely used for fabricating magnetic coils in fusion reactors. Superconducting magnet system represents a key determinant of the thermal efficiency and the construction/operating costs of such a reactor. In consideration of the stability of 11B against fast neutron irradiation and its lower induced radioactivation properties, MgB2 superconductor with 11B serving as the boron source is an alternative candidate for use in fusion reactors with a severe high neutron flux environment. In the present work, the glycine-doped Mg11B2 bulk superconductor was synthesized from isotopic 11B powder to enhance the high field properties. The critical current density was enhanced (103 A·cm−2 at 20 K and 5 T over the entire field in contrast with the sample prepared from natural boron.

  19. Improving magnetic properties of MgB{sub 2} bulk superconductors by synthetic engine oil treatment

    Energy Technology Data Exchange (ETDEWEB)

    Taylan Koparan, E., E-mail: etaylan20@gmail.com [Department of Science Education, Eregli Faculty of Education, Bulent Ecevit University, TR-67300, Zonguldak (Turkey); Savaskan, B. [Energy Systems Engineering, Faculty of Technology, Karadeniz Technical University, 61830, Of, Trabzon (Turkey); Yanmaz, E. [Department of Mechatronics, Faculty of Engineering and Architecture, İstanbul Gelişim University, İstanbul (Turkey)

    2016-08-15

    Highlights: • The effects of synthetic engine oil treatment on magnetic properties of bulk MgB{sub 2} superconductors has been first time investigated and reported. • Synthetic engine oil used as a product which is cheap and a rich carbon source obviously has improved the superconducting magnetic properties of MgB{sub 2}. • The critical current density of all of MgB{sub 2} samples immersed at different standby time in engine oil in whole field range has been better than that of the pure MgB{sub 2} sample. • The MgB{sub 2} sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. - Abstract: The present study focuses on the effects of standby time of the MgB{sub 2} samples immersed in synthetic engine oil on the critical current density ( J{sub c}(H)), magnetic field dependence of the pinning force density f{sub p}(b) and T{sub c} performances of MgB{sub 2} bulk superconductors. Synthetic engine oil was used as a product which is cheap and a rich carbon source. Manufactured MgB{sub 2} pellet samples were immersed at different standby time of 30 min, 120 min, 300 min and 1440 min in synthetic engine oil after the first heating process. Finally, MgB{sub 2} samples immersed in synthetic engine oil were sintered at 1000 °C and kept for 15 min in Ar atmosphere. The critical current density of all of MgB{sub 2} samples immersed at different standby time in engine oil in whole field range was better than that of the pure MgB{sub 2} sample because of the number of the pinning centers. The MgB{sub 2} sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. The J{sub c} value for the pure sample is 2.0 × 10{sup 3} A/cm{sup 2}, whereas for the MgB{sub 2} sample immersed at 300 min standby time in engine oil the J{sub c} is enhanced to 4.8 × 10{sup 3} A/cm{sup 2} at 5 K and 3 T. The superconducting transition temperature (T{sub c}) did not change

  20. Microstructural characterization of LaB6-ZrB2 eutectic composites

    International Nuclear Information System (INIS)

    Wang Shengchang; Wei, W.J.; Zhang Litong

    2003-01-01

    Detail microstructure of LaB 6 -ZrB 2 composites has been characterized by TEM and HRTEM. The directionally solidified ZrB 2 fibers in LaB 6 matrix near LaB 6 -ZrB 2 eutectics present at least three growing relationship systems. In addition to previous report of [001]LaB 6 / [0001]ZrB 2 relationship, [0 anti 11]LaB 6 / [0001]ZrB 2 and [1 anti 20]LaB 6 / [0001]ZrB 2 . were identified. Different with [001]LaB 6 / [0001]ZrB 2 system, the interfaces of [0 anti 11]LaB 6 / [0001]ZrB 2 and [1 anti 20]LaB 6 / [0001]ZrB 2 . show non-coherent and clean interfaces. There is neither glassy phase nor reaction products found at the interfaces (orig.)

  1. Harnessing marketing automation for B2B content marketing

    OpenAIRE

    Järvinen, Joel; Taiminen, Heini

    2016-01-01

    The growing importance of the Internet to B2B customer purchasing decisions has motivated B2B sellers to create digital content that leads potential buyers to interact with their company. This trend has engendered a new paradigm referred to as ‘content marketing.’ This study investigates the organizational processes for developing valuable and timely content to meet customer needs and for integrating content marketing with B2B selling processes. The results of this single case study demonstra...

  2. VizieR Online Data Catalog: Hubble Source Catalog (V1 and V2) (Whitmore+, 2016)

    Science.gov (United States)

    Whitmore, B. C.; Allam, S. S.; Budavari, T.; Casertano, S.; Downes, R. A.; Donaldson, T.; Fall, S. M.; Lubow, S. H.; Quick, L.; Strolger, L.-G.; Wallace, G.; White, R. L.

    2016-10-01

    The HSC v1 contains members of the WFPC2, ACS/WFC, WFC3/UVIS and WFC3/IR Source Extractor source lists from HLA version DR8 (data release 8). The crossmatching process involves adjusting the relative astrometry of overlapping images so as to minimize positional offsets between closely aligned sources in different images. After correction, the astrometric residuals of crossmatched sources are significantly reduced, to typically less than 10mas. The relative astrometry is supported by using Pan-STARRS, SDSS, and 2MASS as the astrometric backbone for initial corrections. In addition, the catalog includes source nondetections. The crossmatching algorithms and the properties of the initial (Beta 0.1) catalog are described in Budavari & Lubow (2012ApJ...761..188B). The HSC v2 contains members of the WFPC2, ACS/WFC, WFC3/UVIS and WFC3/IR Source Extractor source lists from HLA version DR9.1 (data release 9.1). The crossmatching process involves adjusting the relative astrometry of overlapping images so as to minimize positional offsets between closely aligned sources in different images. After correction, the astrometric residuals of crossmatched sources are significantly reduced, to typically less than 10mas. The relative astrometry is supported by using Pan-STARRS, SDSS, and 2MASS as the astrometric backbone for initial corrections. In addition, the catalog includes source nondetections. The crossmatching algorithms and the properties of the initial (Beta 0.1) catalog are described in Budavari & Lubow (2012ApJ...761..188B). Hubble Source Catalog Acknowledgement: Based on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESAC/ESA) and the Canadian Astronomy Data Centre (CADC/NRC/CSA). (2 data files).

  3. ORM-Based Semantics of B2B Transactions

    Science.gov (United States)

    Balsters, H.; van Blommestein, F.

    After widespread implementation of Enterprise Resource Planning and Personal Information Management, the next wave in the application of ICT is headed towards business to business (B2B) communication. B2B has a number of specific aspects, one of them being negotiation. This aspect has been largely neglected by present implementations of standard EDI- or XML-messaging and by B2B webservice implementations. In this paper a precise model is given of the negotiation process. The requirements of a potential Buyer and the offer of a potential Seller are matched and, if the negotiation is successful, a contract is concluded. The negotiation process model is represented in ORM, extended with dynamic constraints. Our model may be implemented in the databases of the trading partners and in message- or service definitions.

  4. A formal treatment of uncertainty sources in a level 2 PSA

    International Nuclear Information System (INIS)

    Ahn, Kwang Il; Yang, Joon Eon

    2003-01-01

    The methodological framework of the level 2 PSA appears to be currently standardized in a formalized fashion, but there have been different opinions on the way the sources of uncertainty are characterized and treated. This is primarily because the level 2 PSA deals with complex phenomenological processes that are deterministic in nature rather than random processes, and there are no probabilistic models characterizing them clearly. As a result, the probabilistic quantification of the level 2 PSA is often subjected to two sources of uncertainty: (a) incomplete modeling of accident pathways or different predictions for the behavior of phenomenological events and (b) expert-to-expert variation in estimating the occurrence probability of phenomenological events. While a clear definition of the two sources of uncertainty involved in the level 2 PSA makes it possible to treat an uncertainty in a consistent manner, careless application of these different sources of uncertainty may produce different conclusions in the decision-making process. The primary purpose of this paper is to characterize typical sources of uncertainty that would often be addressed in the level 2 PSA and their impacts on the PSA level 2 risk results. An additional purpose of this paper is to give a formal approach on how to combine random uncertainties addressed in the level 1 PSA with subjectivistic uncertainties addressed in the level 2 PSA

  5. Electronic Commerce in Tourism in China: B2B or B2C?

    Science.gov (United States)

    Li, Hongxiu; Suomi, Reima

    E-commerce has significantly changed the distribution channels of travel products in the world including China. Online channels are growing important in travel service distribution. In China tourism industry has been developed rapidly with the economic development, more and more international travel service providers are trying to expand their Chinese market through the Internet. This paper sheds lights on the e-commerce development models in China for international travel service providers. It explores the current e-tourism in China from the three different participants in the value chain in tourism industry - consumer, travel agent and travel service provider. The paper also identifies the barriers in B2C arena in international outbound travel market, and discusses the possible approaches for international travel service providers to develop their e-commerce in the huge Chinese market. The results in this study reveal that international travel service providers should focus on B2B model to expand their electronic market in China. B2C development in tourism largely depends on the change of Chinese customers' behavior and the change of international tourism regulations. The findings of the study are expected to assist international travel service providers to understand current e-tourism in China and to support their planning for future e-commerce development in China.

  6. Component Based System Framework for Dynamic B2B Interaction

    NARCIS (Netherlands)

    Hu jinmin, Jinmin; Grefen, P.W.P.J.

    Business-to-Business (B2B) collaboration is becoming a pivotal way to bring today's enterprises to success in the dynamically changing e-business environment. Though many business-to-business protocols are developed to support B2B interaction, none are generally accepted. A B2B system should support

  7. Contextualized B2B Registries

    OpenAIRE

    Radetzki, U; Boniface, M.J.; Surridge, M.

    2007-01-01

    Abstract. Service discovery is a fundamental concept underpinning the move towards dynamic service-oriented business partnerships. The business process for integrating service discovery and underlying registry technologies into busi-ness relationships, procurement and project management functions has not been examined and hence existing Web Service registries lack capabilities required by business today. In this paper we present a novel contextualized B2B registry that supports dynamic regist...

  8. Lattice Thermal Conductivity from Atomistic Simulations: ZrB2 and HfB2

    Science.gov (United States)

    Lawson, John W.; Daw, Murray S.; Bauschlicher, Charles W.

    2012-01-01

    Ultra high temperature ceramics (UHTC) including ZrB2 and HfB2 have a number of properties that make them attractive for applications in extreme environments. One such property is their high thermal conductivity. Computational modeling of these materials will facilitate understanding of fundamental mechanisms, elucidate structure-property relationships, and ultimately accelerate the materials design cycle. Progress in computational modeling of UHTCs however has been limited in part due to the absence of suitable interatomic potentials. Recently, we developed Tersoff style parameterizations of such potentials for both ZrB2 and HfB2 appropriate for atomistic simulations. As an application, Green-Kubo molecular dynamics simulations were performed to evaluate the lattice thermal conductivity for single crystals of ZrB2 and HfB2. The atomic mass difference in these binary compounds leads to oscillations in the time correlation function of the heat current, in contrast to the more typical monotonic decay seen in monoatomic materials such as Silicon, for example. Results at room temperature and at elevated temperatures will be reported.

  9. Il B2B e il paradigma dei costi di transazione (B2B and the Transaction Costs Paradigm

    Directory of Open Access Journals (Sweden)

    Pierluigi Sabbatini

    2012-04-01

    Full Text Available Business to Business (B2B Internet commerce causes a significant contraction of transaction costs. According to the Coase paradigm, we would thus expect a deverticalization of the industry and broader scope for anonymous market mechanisms. In reality, such expectations are not fully borne out by the facts. When the industrial structure is concentrated the B2Bgenerally loses its independence, and is owned by the firms which most contribute to its development, e.g. the ones able to bring the liquidity to it. The B2B governance mechanism established by these firms gives hierarchical mechanisms a role which they do not usually play in extensive, anonymous markets.         JEL Codes: D23, L86Keywords: Cost, Transaction Costs, Transactions

  10. Identification of UGT2B9*2 and UGT2B33 isolated from female rhesus monkey liver.

    Science.gov (United States)

    Dean, Brian; Arison, Byron; Chang, Steve; Thomas, Paul E; King, Christopher

    2004-06-01

    Two UDP-glucuronosyltransferases (UGT2B9(*)2 and UGT2B33) have been isolated from female rhesus monkey liver. Microsomal preparations of the cell lines expressing the UGTs catalyzed the glucuronidation of the general substrate 7-hydroxy-4-(trifluoromethyl)coumarin in addition to selected estrogens (beta-estradiol and estriol) and opioids (morphine, naloxone, and naltrexone). UGT2B9(*)2 displayed highest efficiency for beta-estradiol-17-glucuronide production and did not catalyze the glucuronidation of naltrexone. UGT2B33 displayed highest efficiency for estriol and did not catalyze the glucuronidation of beta-estradiol. UGT2B9(*)2 was found also to catalyze the glucuronidation of 4-hydroxyestrone, 16-epiestriol, and hyodeoxycholic acid, while UGT2B33 was capable of conjugating 4-hydroxyestrone, androsterone, diclofenac, and hyodeoxycholic acid. Three glucocorticoids (cortisone, cortisol, and corticosterone) were not substrates for glucuronidation by liver or kidney microsomes or any expressed UGTs. Our current data suggest the use of beta-estradiol-3-glucuronidation, beta-estradiol-17-glucuronidation, and estriol-17-glucuronidation to assay UGT1A01, UGT2B9(*)2, and UGT2B33 activity in rhesus liver microsomes, respectively.

  11. Using i2b2 to Bootstrap Rural Health Analytics and Learning Networks.

    Science.gov (United States)

    Harris, Daniel R; Baus, Adam D; Harper, Tamela J; Jarrett, Traci D; Pollard, Cecil R; Talbert, Jeffery C

    2016-08-01

    We demonstrate that the open-source i2b2 (Informatics for Integrating Biology and the Bedside) data model can be used to bootstrap rural health analytics and learning networks. These networks promote communication and research initiatives by providing the infrastructure necessary for sharing data and insights across a group of healthcare and research partners. Data integration remains a crucial challenge in connecting rural healthcare sites with a common data sharing and learning network due to the lack of interoperability and standards within electronic health records. The i2b2 data model acts as a point of convergence for disparate data from multiple healthcare sites. A consistent and natural data model for healthcare data is essential for overcoming integration issues, but challenges such as those caused by weak data standardization must still be addressed. We describe our experience in the context of building the West Virginia/Kentucky Health Analytics and Learning Network, a collaborative, multi-state effort connecting rural healthcare sites.

  12. Combustion synthesis of AlB2-Al2O3 composite powders with AlB2 nanowire structures

    Science.gov (United States)

    Yang, Pan; Xiao, Guoqing; Ding, Donghai; Ren, Yun; Yang, Shoulei; Lv, Lihua; Hou, Xing

    2018-05-01

    Using of Al and B2O3 powders as starting materials, and Mg-Al alloy as additives, AlB2-Al2O3 composite powders with AlB2 nanowire structures were successfully fabricated via combustion synthesis method in Ar atmosphere at a pressure of 1.5 MPa. The effect of different amount of Mg-Al alloy on the phase compositions and morphology of the combustion products was investigated. The results revealed that AlB2 and Al2O3 increased, whereas Al decreased with the content of Mg-Al alloy increasing. The impurities MgAl2O4 and AlB12 would exist in the sample with adding of 18 wt% Mg-Al alloy. Interestingly, FESEM/TEM/EDS results showed that AlB2 nanowires were observed in the products when the content of Mg-Al alloy is 6 wt% and 12 wt%. The more AlB2 nanowires can be found as the content of Mg-Al alloy increased. And the yield of AlB2 nanowires with the diameter of about 200 nanometers (nm) and the length up to several tens of micrometers (μm) in the combustion product is highest when the content of Mg-Al alloy is 12 wt%. The vapor, such as Mg-Al (g), B2O2 (g), AlO (g) and Al2O (g), produced during the process of combustion synthesis, reacted with each other to yield AlB2 nanowires by vapor-solid (VS) mechanism and the corresponding model was also proposed.

  13. Long Wavelength Electromagnetic Light Bullets Generated by a 10.6 micron CO2 Ultrashort Pulsed Source

    Science.gov (United States)

    2016-11-29

    AFRL-AFOSR-VA-TR-2016-0365 Long Wavelength Electromagnetic Light Bullets Generated by a 10.6 micron CO2 Ultrashort Pulsed Source Jerome Moloney...SUBTITLE "Long Wavelength Electromagnetic Light Bullets Generated by a 10.6 micron CO2 Ultrashort Pulsed Source 5a. CONTRACT NUMBER FA9550-15-1-0272 5b...Wavelength Electromagnetic Light Bullets Generated by a 10 µm CO2 Ultrashort Pulsed Source Grant/Contract Number AFOSR assigned control number. It must

  14. New microfocus bremsstrahlung source based on betatron B-18 for high-resolution radiography and tomography

    Science.gov (United States)

    Rychkov, M. M.; Kaplin, V. V.; Malikov, E. L.; Smolyanskiy, V. A.; Stepanov, I. B.; Lutsenko, A. S.; Gentsel'man, V.; Vas'kovskiy, I. K.

    2018-01-01

    New microfocus source of hard bremsstrahlung (photon energy > 1 MeV), based on the betatron B-18 with a narrow Ta target inside, for high-resolution radiography and tomography is presented. The first studies of the source demonstrate its possibilities for practical applications to detect the microdefects in products made from heavy materials and to control gaps in joints of parts of composite structures of engineering facilities. The radiography method was used to investigate a compound object consisting of four vertically arranged steel bars between which surfaces were exposed gaps of 10 μm in width. The radiographic image of the object, obtained with a magnification of 2.4, illustrates the good sensitivity of detecting the gaps between adjacent bars, due to the small width of the linear focus of the bremsstrahlung source.

  15. Deliberate and Crisis Action Planning and Execution Segments Increment 2B (DCAPES Inc 2B)

    Science.gov (United States)

    2016-03-01

    2016 Major Automated Information System Annual Report Deliberate and Crisis Action Planning and Execution Segments Increment 2B (DCAPES Inc 2B...Information Program Name Deliberate and Crisis Action Planning and Execution Segments Increment 2B (DCAPES Inc 2B) DoD Component Air Force Responsible Office...been established. DCAPES Inc 2B 2016 MAR UNCLASSIFIED 4 Program Description Deliberate and Crisis Action Planning and Execution Segments (DCAPES) is

  16. An electrostatic Si e-gun and a high temperature elemental B source for Si heteroepitaxial growth

    Science.gov (United States)

    Scarinci, F.; Casella, A.; Lagomarsino, S.; Fiordelisi, M.; Strappaveccia, P.; Gambacorti, N.; Grimaldi, M. G.; Xue, LiYing

    1996-08-01

    In this paper we present two kind of sources used in Si MBE growth: a Si source where an electron beam is electrostatically deflected onto a Si rod and a high temperature B source to be used for p-doping. Both sources have been designed and constructed at IESS. The Si source is constituted of a Si rod mounted on a 3/4″ flange with high-voltage connector. A W filament held at high voltage (up to 2000 V) is heated by direct current. Electrons from the filament are electrostatically focused onto the Si rod which is grounded. This mounting allows a minimum heating dispersion and no contamination, because the only hot objects are the Si rod and the W filament which is mounted in such a way that it cannot see the substrate. Growth rates of 10 Å/min on a substrate at 20 cm from the source have been measured. Auger and LEED have shown no contamination. The B source is constituted of a graphite block heated by direct current. A pyrolitic graphite crucible put in the graphite heater contains the elemental B. The cell is water cooled and contains Ta screens to avoid heat dispersion. It has been tested up to a temperature of 1700°C. P-doped Si 1- xGe x layers have been grown and B concentration has been measured by SIMS. A good control and reproducibility has been attained.

  17. Report on the engineering test of the LBL 30 second neutral beam source for the MFTF-B project

    International Nuclear Information System (INIS)

    Vella, M.C.; Pincosy, P.A.; Hauck, C.A.; Pyle, R.V.

    1984-08-01

    Positive ion based neutral beam development in the US has centered on the long pulse, Advanced Positive Ion Source (APIS). APIS eventually focused on development of 30 second sources for MFTF-B. The Engineering Test was part of competitive testing of the LBL and ORNL long pulse sources carried out for the MFTF-B Project. The test consisted of 500 beam shots with 80 kV, 30 second deuterium, and was carried out on the Neutral Beam Engineering Test Facility (NBETF). This report summarizes the results of LBL testing, in which the LBL APIS demonstrated that it would meet the requirements for MFTF-B 30 second sources. In part as a result of this test, the LBL design was found to be suitable as the baseline for a Common Long Pulse Source design for MFTF-B, TFTR, and Doublet Upgrade

  18. Thermoelastic properties of ScB2, TiB2, YB4 and HoB4

    DEFF Research Database (Denmark)

    Waskowska, A.; Gerward, L.; Staun Olsen, J.

    2011-01-01

    (4)GPa). No pressure-induced phase transformations are observed in any of the above borides up to about 20GPa. A continuous temperature-driven orthorhombic distortion is observed for HoB4 below 285K. Values of the thermal expansion coefficient are reported for ScB2 and HoB4 at 293, 200 and 100K...

  19. Short syntheses of enantiopure calystegine B-2, B-3, and B-4

    DEFF Research Database (Denmark)

    Skaanderup, Philip Robert; Madsen, Robert

    2001-01-01

    Calystegine B-2 B-3, and B-4 have been prepared in 5 steps from the benzyl protected methyl 6-iodoglycopyranosides of glucose, galactose and mannose, respectively, by using a zinc-mediated domino reaction followed by ring-closing olefin metathesis as the key steps.......Calystegine B-2 B-3, and B-4 have been prepared in 5 steps from the benzyl protected methyl 6-iodoglycopyranosides of glucose, galactose and mannose, respectively, by using a zinc-mediated domino reaction followed by ring-closing olefin metathesis as the key steps....

  20. H.B. Robinson-2 pressure vessel benchmark

    Energy Technology Data Exchange (ETDEWEB)

    Remec, I.; Kam, F.B.K.

    1998-02-01

    The H. B. Robinson Unit 2 Pressure Vessel Benchmark (HBR-2 benchmark) is described and analyzed in this report. Analysis of the HBR-2 benchmark can be used as partial fulfillment of the requirements for the qualification of the methodology for calculating neutron fluence in pressure vessels, as required by the U.S. Nuclear Regulatory Commission Regulatory Guide DG-1053, Calculational and Dosimetry Methods for Determining Pressure Vessel Neutron Fluence. Section 1 of this report describes the HBR-2 benchmark and provides all the dimensions, material compositions, and neutron source data necessary for the analysis. The measured quantities, to be compared with the calculated values, are the specific activities at the end of fuel cycle 9. The characteristic feature of the HBR-2 benchmark is that it provides measurements on both sides of the pressure vessel: in the surveillance capsule attached to the thermal shield and in the reactor cavity. In section 2, the analysis of the HBR-2 benchmark is described. Calculations with the computer code DORT, based on the discrete-ordinates method, were performed with three multigroup libraries based on ENDF/B-VI: BUGLE-93, SAILOR-95 and BUGLE-96. The average ratio of the calculated-to-measured specific activities (C/M) for the six dosimeters in the surveillance capsule was 0.90 {+-} 0.04 for all three libraries. The average C/Ms for the cavity dosimeters (without neptunium dosimeter) were 0.89 {+-} 0.10, 0.91 {+-} 0.10, and 0.90 {+-} 0.09 for the BUGLE-93, SAILOR-95 and BUGLE-96 libraries, respectively. It is expected that the agreement of the calculations with the measurements, similar to the agreement obtained in this research, should typically be observed when the discrete-ordinates method and ENDF/B-VI libraries are used for the HBR-2 benchmark analysis.

  1. 2D accelerator design for SITEX negative ion source

    International Nuclear Information System (INIS)

    Whealton, J.H.; Raridon, R.J.; McGaffey, R.W.; McCollough, D.H.; Stirling, W.L.; Dagenhart, W.K.

    1983-01-01

    Solving the Poisson-Vlasov equations where the magnetic field, B, is assumed constant, we optimize the optical system of a SITEX negative ion source in infinite slot geometry. Algorithms designed to solve the above equations were modified to include the curved emitter boundary data appropriate to a negative ion source. Other configurations relevant to negative ion sources are examined

  2. Modification to the accelerator of the NBI-1B ion source for improving the injection efficiency

    International Nuclear Information System (INIS)

    Kim, T. S.; Jeong, S. H.; Chang, D. H.; In, S. R.; Park, M.; Jung, B. K.; Lee, K. W.; Wang, S. J.; Bae, Y. S.; Park, H. T.; Kim, J. S.; Cho, W.; Choi, D. J.

    2016-01-01

    Minimizing power loss of a neutral beam imposes modification of the accelerator of the ion source for further improvement of the beam optics. The beam optics can be improved by focusing beamlets. The injection efficiencies by the steering of ion beamlets are investigated numerically to find the optimum modification of the accelerator design of the NBI-1B ion source. The beam power loss was reduced by aperture displacement of three edge beamlets arrays considering power loadings on the beamline components. Successful testing and operation of the ion source at 60 keV/84% of injection efficiency led to the possibility of enhancing the system capability to a 2.4 MW power level at 100 keV/1.9 μP

  3. Design of a thermal neutron field by 252Cf source for measurement of 10B concentrations in the blood samples for BNCT

    International Nuclear Information System (INIS)

    Naito, H.; Sakurai, Y.; Maruhashi, A.

    2006-01-01

    10 B concentrations in the blood samples for BNCT has been estimated due to amounts of prompt gamma rays from 10 B in the fields of thermal neutrons from a special guide tube attached to research reactor. A system using radioisotopes as the source of thermal neutron fields has advantages that are convenient and low cost because it doesn't need running of a reactor or an accelerator. The validity of 252 Cf as a neutron source for 10 B concentrations detection system was investigated. This system is composed of D 2 O moderator, Pb reflector/filter, C reflector, and LiF filter. A thermal neutron field with low background gamma-rays is obtained. A large source of 252 Cf is required to obtain a sufficient flux. (author)

  4. B2B Integration in Global Supply Chains

    DEFF Research Database (Denmark)

    Schubert, Petra; Legner, Christine

    2011-01-01

    The competitiveness of businesses is increasingly dependent on their electronic networks with customers, suppliers, and partners. While the strategic and operational impact of external integration and IOS adoption has been extensively studied, much less attention has been paid to the organizational...... and technical design of electronic relationships. The objective of our longitudinal research project is the development of a framework for understanding and explaining B2B integration. Drawing on existing literature and empirical cases we present a reference model (a classification scheme for B2B Integration...

  5. Experiences and Future Expectations towards Online Courses--An Empirical Study of the B2C-and B2B-Segments

    Science.gov (United States)

    Krämer, Andreas; Böhrs, Sandra

    2016-01-01

    This article explores the future potential for the development of online courses. The findings are based on an empirical study with 3 sample groups: (1) B2C segment in Germany, (2) B2C segment in the United States, and (3) B2B segment (international). In the first step the status quo of the use of e-learning in general and online courses in…

  6. Source apportionment of ambient PM2.5 in Santiago, Chile: 1999 and 2004 results.

    Science.gov (United States)

    Jorquera, Héctor; Barraza, Francisco

    2012-10-01

    A receptor model analysis has been applied to ambient PM(2.5) measurements taken at Santiago, Chile (33.5°S, 70.7°W) in 2004 (117 samples) and in 1999 (95 samples) on a receptor site on the eastern side of the city. For both campaigns, six sources have been identified at Santiago and their contributions in 1999/2004 are: motor vehicles: 28 ± 2.5/31.2 ± 3.4%, wood burning: 24.8 ± 2.3/28.9 ± 3.3%, sulfates: 18.8 ± 1.7/16.2 ± 2.5%, marine aerosol: 13 ± 2.1/9.9 ± 1.5%, copper smelters: 11.5 ± 1.4/9.7 ± 3.3% and soil dust: 3.9 ± 1.5/4.0 ± 2.4%. Hence relative contributions are statistically the same but the absolute contributions have been reduced because ambient PM(2.5) has decreased from 34.2 to 25.1 μg/m(3) between 1999 and 2004 at Santiago. Similarity of results for both data sets - analyzed with different techniques at different laboratory facilities - shows that the analysis performed here is robust. Source identification was carried out by inspection of key species in source profiles, seasonality of source contributions, comparison with published source profiles and by looking at wind trajectories computed using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) from USA's National Oceanic and Atmospheric Administration (NOAA); for the wood burning sources the MODIS burned area daily product was used to confirm wildfire events along the year. Using this combined methodology we have shown conclusively that: a) marine air masses do reach Santiago's basin in significant amounts but combined with anthropogenic sources; b) all copper smelters surrounding Santiago - and perhaps coal-fired power plants as well - contribute to ambient PM(2.5); c) wood burning is the second largest source, coming from residential wood burning in fall and winter and from regional wildfires in spring and summer. The results of the present analysis can be used to improve emission inventories, air quality forecasting systems and cost-benefit analyses at local

  7. Comparison of monoclonal antibodies and rabbit antisera in B2 microglobulin (B2m) radioimmunoassay

    International Nuclear Information System (INIS)

    Vincent, C.

    1981-01-01

    Human B2m is a globular protein devoid of carbohydrates and is composed of 100 aminoacids with an intrachain disulfide bridge in position 25-81. Its aminoacid sequence and three dimensional structure shows a partial homology with the constant domains of immunoglobulins. B2m has been detected at the surface of nearly all cell types with the exception of erythrocytes and trophoblastic cells and also in all biological fluids. On the cell surface B2m is found non-covalently associated with HLA molecules, and in serum and urine only a small part of the B2m is associated with HLA heavy chain, the remaining is found as free B2m. The aim of this paper is firstly to try to demonstrate the presence of two types of epitopes one of them specific of free B2m and secondly to compare monoclonal antibodies with rabbit antisera for B2m radioimmunoassay. (Auth.)

  8. A Detector for 2-D Neutron Imaging for the Spallation Neutron Source

    International Nuclear Information System (INIS)

    Britton, Charles L. Jr.; Bryan, W.L.; Wintenberg, Alan Lee; Clonts, Lloyd G.; Warmack, Robert J. Bruce; McKnight, Timothy E.; Frank, Steven Shane; Cooper, Ronald G.; Dudney, Nancy J.; Veith, Gabriel M.

    2006-01-01

    We have designed, built, and tested a 2-D pixellated thermal neutron detector. The detector is modeled after the MicroMegas-type structure previously published for collider-type experiments. The detector consists of a 4X4 square array of 1 cm 2 pixels each of which is connected to an individual preamplifier-shaper-data acquisition system. The neutron converter is a 10B film on an aluminum substrate. We describe the construction of the detector and the test results utilizing 252Cf sources in Lucite to thermalize the neutrons. Drift electrode (Aluminum) Converter (10B) 3 mm Conversion gap neutron (-900 V)

  9. Evidence for multiple polytypes of semiconducting boron carbide (C2B10) from electronic structure

    International Nuclear Information System (INIS)

    Lunca-Popa, Petru; Brand, J I; Balaz, Snjezana; Rosa, Luis G; Boag, N M; Bai Mengjun; Robertson, B W; Dowben, P A

    2005-01-01

    Boron carbides fabricated via plasma enhanced chemical vapour deposition from different isomeric source compounds with the same C 2 B 10 H 12 closo-icosahedral structure result in materials with very different direct (optical) band gaps. This provides compelling evidence for the existence of multiple polytypes of C 2 B 10 boron carbide and is consistent with electron diffraction results

  10. The role of TiB2 in strengthening TiB2 reinforced aluminium casting composites

    International Nuclear Information System (INIS)

    Chen, Z; Kang, H; Zhao, Y; Zheng, Y; Wang, T

    2016-01-01

    With an aim of developing high quality in situ TiB 2 reinforced aluminium foundry alloy based composites, the conventional direct synthesis method was modified into a two-step route. In step one we optimized the halide salt route to fabricate in situ TiB 2 particulate reinforced aluminium matrix composites and in step two we investigated the effects of the Al-5wt.% TiB 2 composite, as a “master composite”, on strengthening the practical foundry alloys. The in situ formed TiB 2 particles play two roles while strengthening the composites: (1) The grain refinement effect that improves the quality of the alloy matrix; and (2) The interactions between the hard particulates and the matrix add extra increment to the material strength. In different alloy systems, TiB 2 may play distinct roles in these two aspects (figure 1). Further analysis of the strengthening mechanisms shows that particle agglomeration behaviour during solidification is responsible for the latter one. The present work details the role of TiB 2 in strengthening TiB 2 reinforced aluminium casting composites. (paper)

  11. Growth analysis of UV-B-irradiated cucumber seedlings as influenced by photosynthetic photon flux source and cultivar

    International Nuclear Information System (INIS)

    Krizek, D.T.; Mirecki, R.M.; Kramer, G.F.

    1994-01-01

    A growth analysis was made of ultraviolet-B (UV-B)-sensitive (Poinsett) and insensitive (Ashley) cultivars of Cucuumis satives L. grown in growth chambers at 600 μmol m −2 s −1 of photosynthetic photon flux (PPF) provided by red- and far-red-deficient metal halide (MH) or blue- and UV-A-deficient high pressure sodium/deluxe f HPS/DX) lamps. Plants were irradiated 6 h daily with 0.2 f-UV-B) or 18.2 C+UV-B) kJ m −2 day −1 of biologically effective UV-B for 8 or 15 days from time of seeding. In general, plants given supplemental UV-B for 15 days showed lower leaf area ratio (LARs, and higher specific leaf mass (SLM) mean relative growth rate (MRGR) and net assimilation rate (NAR) than that of control plants, but they showed no difference in leaf mass ratio (LMR), Plants grown under HPS/DX lamps vs MH lamps showed higher SLM and NAR. lower LAR and LMR. hut no difference in MRGR. LMR was the only growth parameter affected by cultivar: at 15 days, it was slightly greater in Poinsett than in Ashley. There were no interactive effects of UV-B. PPF source or cultivar on any of the growth parameters determined, indicating that the choice of either HPS/DX or MH lamps should not affect growth response to UV-B radiation. This was true even though leaves of UV-B-irradiated plants grown under HPS/DX lamps have been shown to have greater chlorosis than those grown under MH lamps. (author)

  12. Construction of the irreducibles of B(2, 2)

    International Nuclear Information System (INIS)

    Melas, Evangelos

    2006-01-01

    The ordinary Bondi-Metzner-Sachs (BMS) group B is the common asymptotic symmetry group of all radiating, asymptotically flat, Lorentzian spacetimes. As such, B is the best candidate for the universal symmetry group of general relativity. However, in studying quantum gravity, spacetimes with signatures other than the usual Lorentzian one and complex spacetimes are frequently considered. Generalizations of B appropriate to these other signatures have been defined earlier. In particular, the generalization B(2, 2) appropriate to the ultrahyperbolic signature (+, +, -, -) has been described in detail, and the study of its irreducible unitary representations (IRs) of B(2, 2) has been initiated. The infinite little groups have been given explicitly, but the finite little groups have only been partially described. This study is completed by describing in detail the finite little groups and by giving all the necessary information in order to construct the IRs of B(2, 2) in all cases

  13. Long term observations of B2 1215+30 with veritas

    International Nuclear Information System (INIS)

    Aliu, E.; Errando, M.; Archambault, S.; Arlen, T.; Aune, T.; Beilicke, M.; Buckley, J. H.; Bugaev, V.; Benbow, W.; Bird, R.; Bouvier, A.; Cesarini, A.; Connolly, M. P.; Ciupik, L.; Cui, W.; Feng, Q.; Finley, J. P.; Dumm, J.; Falcone, A.; Federici, S.

    2013-01-01

    We report on VERITAS observations of the BL Lac object B2 1215+30 between 2008 and 2012. During this period, the source was detected at very high energies (VHEs; E > 100 GeV) by VERITAS with a significance of 8.9σ and showed clear variability on timescales larger than months. In 2011, the source was found to be in a relatively bright state and a power-law fit to the differential photon spectrum yields a spectral index of 3.6 ± 0.4 stat ± 0.3 syst with an integral flux above 200 GeV of (8.0 ± 0.9 stat ± 3.2 syst ) × 10 –12 cm –2 s –1 . No short term variability could be detected during the bright state in 2011. Multi-wavelength data were obtained contemporaneously with the VERITAS observations in 2011 and cover optical (Super-LOTIS, MDM, Swift/UVOT), X-ray (Swift/XRT), and gamma-ray (Fermi-LAT) frequencies. These were used to construct the spectral energy distribution (SED) of B2 1215+30. A one-zone leptonic model is used to model the blazar emission and the results are compared to those of MAGIC from early 2011 and other VERITAS-detected blazars. The SED can be reproduced well with model parameters typical for VHE-detected BL Lac objects.

  14. Performance enhancement of Ge-on-Insulator tunneling FETs with source junctions formed by low-energy BF2 ion implantation

    Science.gov (United States)

    Katoh, Takumi; Matsumura, Ryo; Takaguchi, Ryotaro; Takenaka, Mitsuru; Takagi, Shinichi

    2018-04-01

    To clarify the process of formation of source regions of high-performance Ge n-channel tunneling field-effect transistors (TFETs), p+-n junctions formed by low-energy ion implantation (I/I) of BF2 atoms are characterized. Here, the formation of p+-n junctions with steep B profiles and low junction leakage is a key issue. The steepness of 5.7 nm/dec in profiles of B implanted into Ge is obtained for BF2 I/I at 3 keV with a dose of 4 × 1014 cm-2. Ge-on-insulator (GOI) n-TFETs with the source tunnel junctions formed by low-energy B and BF2 I/I are fabricated on GOI substrates and the device operation is confirmed. Although the performance at room temperature is significantly degraded by the source junction leakage current, an I on/I off ratio of 105 and the minimum sub-threshold swing (S.S.) of 130 mV/dec are obtained at 10 K. It is found that GOI n-TFETs with steeper B profiles formed by BF2 I/I have led to higher on current and a lower sub-threshold slope, demonstrating the effectiveness of steep B profiles in enhancing the GOI TFET performance.

  15. On the Nature of Ultra-faint Dwarf Galaxy Candidates. II. The Case of Cetus II

    Science.gov (United States)

    Conn, Blair C.; Jerjen, Helmut; Kim, Dongwon; Schirmer, Mischa

    2018-04-01

    We obtained deep Gemini GMOS-S g, r photometry of the ultra-faint dwarf galaxy candidate Cetus II with the aim of providing stronger constraints on its size, luminosity, and stellar population. Cetus II is an important object in the size–luminosity plane, as it occupies the transition zone between dwarf galaxies and star clusters. All known objects smaller than Cetus II (r h ∼ 20 pc) are reported to be star clusters, while most larger objects are likely dwarf galaxies. We found a prominent excess of main-sequence stars in the color–magnitude diagram of Cetus II, best described by a single stellar population with an age of 11.2 Gyr, metallicity of [Fe/H] = ‑1.28 dex, an [α/Fe] = 0.0 dex at a heliocentric distance of 26.3 ± 1.2 kpc. As well as being spatially located within the Sagittarius dwarf tidal stream, these properties are well matched to the Sagittarius galaxy’s Population B stars. Interestingly, like our recent findings on the ultra-faint dwarf galaxy candidate Tucana V, the stellar field in the direction of Cetus II shows no evidence of a concentrated overdensity despite tracing the main sequence for over six magnitudes. These results strongly support the picture that Cetus II is not an ultra-faint stellar system in the Milky Way halo, but made up of stars from the Sagittarius tidal stream.

  16. Strength anomaly in B2 FeAl single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimi, K.; Hanada, S.; Yoo, M.H. [Oak Ridge National Lab., TN (United States); Matsumoto, N. [Tohoku Univ. (Japan). Graduate School

    1994-12-31

    Strength and deformation microstructure of B2 Fe-39 and 48%Al single crystals (composition given in atomic percent), which were fully annealed to remove frozen-in vacancies, have been investigated at temperatures between room temperature and 1073K. The hardness of as-homogenized Fe-48Al is higher than that of as-homogenized Fe-39Al while after additional annealing at 698K the hardness of Fe-48Al becomes lower than that of Fe-39Al. Fe-39Al single crystals slowly cooled after homogenizing at a high temperature were deformed in compression as a function of temperature and crystal orientation. A peak of yield strength appears around 0.5T{sub m} (T{sub m} = melting temperature). The orientation dependence of the critical resolved shear stress does not obey Schmid`s law even at room temperature and is quite different from that of b.c.c. metals and B2 intermetallics at low temperatures. At the peak temperature slip transition from <111>-type to <001>-type is found to occur macroscopically and microscopically, while it is observed in TEM that some of the [111] dislocations decompose into [101] and [010] on the (1096I) plane below the peak temperature. The physical sources for the positive temperature dependence of yield stress of B2 FeAl are discussed based on the obtained results.

  17. Managing Innovation Through Social Media in B2B SME-Context

    DEFF Research Database (Denmark)

    Lutz, Salla; Madsen, Svend Ole; Brink, Tove

    2015-01-01

    This paper shed light on how social media application can enhance innovation management in SME B2B context. Our study employs a qualitative case study approach with four B2B SMEs for in-depth research in the period from October 2013 to October 2014. The B2B SME managers aim for open business mode...

  18. Electronic and elastic properties of new semiconducting oP12-type RuB2 and OsB2

    International Nuclear Information System (INIS)

    Hao Xianfeng; Xu Yuanhui; Gao Faming

    2011-01-01

    Using first-principles total energy calculations we investigate the structural, elastic and electronic properties of new hypothetical oP 12 -type phase RuB 2 and OsB 2 . The calculations indicate that the oP 12 -type phase RuB 2 and OsB 2 are thermodynamically and mechanically stable. Remarkably, the new phases RuB 2 and OsB 2 are predicted to be semiconductors, and the appearance of band gaps is ascribed to the enhanced B-B covalent hybridization. Compared to metallic oP 6 -type RuB 2 and OsB 2 phases, the new phases possess similar mechanical properties and hardness. The combination of the probability of tunable electronic properties, strong stiffness and high hardness make RuB 2 and OsB 2 attractive and interesting for advanced applications.

  19. Observation of B+ -> J/psi 3 pi(+)2 pi(-) and B+ -> psi (2S)pi(+)pi(+)pi(-) decays

    OpenAIRE

    Aaij, R.; Adeva, B.; Adinolfi, M.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M. H.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A. Jr; Amato, S.; Amerio, S.; Amhis, Y.

    2017-01-01

    The decays B+-> J/psi 3 pi(+)2 pi(-) and B+ -> psi(2S)pi(+)pi(+)pi(-) are observed for the first time using a data sample corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment in proton- proton collisions at the centre-of-mass energies of 7 and 8 TeV. The branching fractions relative to that of B+ -> psi(2S)K+ are measured to be B(B+-> J/psi 3 pi(+)2 pi(-))/B(B+ -> psi (2S)K+) = (1.88 +/- 0.17 +/- 0.09)x10(-2). B(B+ -> psi(2S)pi(+)pi(+)pi(-))/B(B+ -> psi (2...

  20. Synthesis of ZrB{sub 2}-SiC ceramic composites from a single-source precursor

    Energy Technology Data Exchange (ETDEWEB)

    Arish, Dasan, E-mail: arishd@rediffmail.com [Université of Limoges, SPCTS-CNRS, UMR 7315, Centre Européen de la Céramique (CEC), 12 Rue Atlantis, F-87068, Limoges Cedex (France); Shiju, Chellan [Synthetic Products Division, Corporate R & D Center (CRDC), HLL Lifecare Limited, Thiruvananthapuram, Kerala (India); Joseyphus, Raphael Selwin, E-mail: rsjoseyphus@gmail.com [PG & Research, Department of Chemistry, Mar Ivanios College (Autonomous), Thiruvananthapuram, 695015, Kerala (India); Pushparajan, Joseph [Travancore Titanium Products Ltd., Kochuveli, Thiruvananthapuram, 695021, Kerala (India)

    2017-06-15

    Preceramic polymer zirconoborosiloxane was synthesized from the reaction with boric acid, diphenyldiethoxysilane and zirconium (IV) propoxide via solventless process. The thermogravimetric analysis of the polymer showed that ceramic yield as decomposition product at 900 °C was 71%. The pyrolysis of zirconoborosiloxane in an argon gas environment was investigated as standard pyrolytic process up to 1650 °C. Microstructure evolution of ceramic phases was made by means of Fourier transform infrared, Raman spectroscopy, X-ray diffraction and scanning electron microscope analysis. The results clearly demonstrated the pyrolysis products at 1650 °C consist of totally non-oxide ceramic phases of β-SiC, ZrB{sub 2} and free carbon. - Highlights: • Preceramic polymer zirconoborosiloxane was synthesized by non-aqueous solventless process. • Non-oxide ZrB{sub 2}-SiC composites could be obtained from the pyrolysed products at 1650 °C. • Free carbon content was identified by Raman spectroscopy.

  1. Systems Li2B4O7 (Na2B4O7, K2B4O7)-N2H3H4OH-H2O at 25 deg C

    International Nuclear Information System (INIS)

    Skvortsov, V.G.; Sadetdinov, Sh.V.; Akimov, V.M.; Mitrasov, Yu.N.; Petrova, O.V.; Klopov, Yu.N.

    1994-01-01

    Phase equilibriums in the Li 2 B 4 O 7 (Na 2 B 4 O 7 , K 2 B 4 O 7 )-N 2 H 3 H 4 OH-H 2 O systems were investigated by methods of isothermal solubility, refractometry and PH-metry at 25 deg C for the first time. Lithium and sodium tetraborates was established to form phases of changed composition mM 2 B 4 O 7 ·nN 2 H 3 C 2 H 4 OH·XH 2 O, where M=Li, Na with hydrazine ethanol. K 2 B 4 O 7 ·4H 2 O precipitates in solid phase in the case of potassium salt. Formation of isomorphous mixtures was supported by X-ray diffraction and IR spectroscopy methods

  2. GRIN2B encephalopathy

    DEFF Research Database (Denmark)

    Platzer, Konrad; Yuan, Hongjie; Schuetz, Hannah

    2017-01-01

    BACKGROUND: We aimed for a comprehensive delineation of genetic, functional and phenotypic aspects of GRIN2B encephalopathy and explored potential prospects of personalised medicine. METHODS: Data of 48 individuals with de novo GRIN2B variants were collected from several diagnostic and research c...

  3. Electronic and elastic properties of new semiconducting oP(12)-type RuB(2) and OsB(2).

    Science.gov (United States)

    Hao, Xianfeng; Xu, Yuanhui; Gao, Faming

    2011-03-30

    Using first-principles total energy calculations we investigate the structural, elastic and electronic properties of new hypothetical oP(12)-type phase RuB(2) and OsB(2). The calculations indicate that the oP(12)-type phase RuB(2) and OsB(2) are thermodynamically and mechanically stable. Remarkably, the new phases RuB(2) and OsB(2) are predicted to be semiconductors, and the appearance of band gaps is ascribed to the enhanced B-B covalent hybridization. Compared to metallic oP(6)-type RuB(2) and OsB(2) phases, the new phases possess similar mechanical properties and hardness. The combination of the probability of tunable electronic properties, strong stiffness and high hardness make RuB(2) and OsB(2) attractive and interesting for advanced applications. © 2011 IOP Publishing Ltd

  4. Scope of Internal Marketing in B2B Companies

    OpenAIRE

    Nigam, Niharika

    2007-01-01

    Abstract Previous studies have focused on "internal marketing" from services marketing perspective. There is, therefore, a great dearth of in-depth research on its application to other business types. This research attempts to find the scope of internal marketing in B2B companies. The purpose of this research is to closely examine the elements, their linkage, tools and applications of Internal marketing when applied to B2B settings. Internal marketing, the application of marketing managem...

  5. Si(001):B gas-source molecular-beam epitaxy: Boron surface segregation and its effect on film growth kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H.; Glass, G.; Spila, T.; Taylor, N.; Park, S.Y.; Abelson, J.R.; Greene, J.E. [Department of Materials Science, Coordinated Science Laboratory, and Materials Research Laboratory, University of Illinois, 1101 West Springfield, Urbana, Illinois 61801 (United States)

    1997-09-01

    B-doped Si(001) films, with concentrations C{sub B} up to 1.7{times}10{sup 22}cm{sup {minus}3}, were grown by gas-source molecular-beam epitaxy from Si{sub 2}H{sub 6} and B{sub 2}H{sub 6} at T{sub s}=500{endash}800{degree}C. D{sub 2} temperature-programed desorption (TPD) spectra were then used to determine B coverages {theta}{sub B} as a function of C{sub B} and T{sub s}. In these measurements, as-deposited films were flash heated to desorb surface hydrogen, cooled, and exposed to atomic deuterium until saturation coverage. Strong B surface segregation was observed with surface-to-bulk B concentration ratios ranging up to 1200. TPD spectra exhibited {beta}{sub 2} and {beta}{sub 1} peaks associated with dideuteride and monodeuteride desorption as well as lower-temperature B-induced peaks {beta}{sub 2}{sup {asterisk}} and {beta}{sub 1}{sup {asterisk}}. Increasing {theta}{sub B} increased the area under {beta}{sub 2}{sup {asterisk}} and {beta}{sub 1}{sup {asterisk}} at the expense of {beta}{sub 2} and {beta}{sub 1} and decreased the total D coverage {theta}{sub D}. The TPD results were used to determine the B segregation enthalpy, {minus}0.53eV, and to explain and model the effects of high B coverages on Si(001) growth kinetics. Film deposition rates R increase by {ge}50{percent} with increasing C{sub B}{tilde {gt}}1{times}10{sup 19}cm{sup {minus}3} at T{sub s}{le}550{degree}C, due primarily to increased H desorption rates from B-backbonded Si adatoms, and decrease by corresponding amounts at T{sub s}{ge}600{degree}C due to decreased adsorption site densities. At T{sub s}{ge}700{degree}C, high B coverages also induce {l_brace}113{r_brace} facetting. {copyright} {ital 1997 American Institute of Physics.}

  6. Experimental Investigation and Thermodynamic Modeling of the B2O3-FeO-Fe2O3-Nd2O3 System for Recycling of NdFeB Magnet Scrap

    Science.gov (United States)

    Jakobsson, Lars Klemet; Tranell, Gabriella; Jung, In-Ho

    2017-02-01

    NdFeB magnet scrap is an alternative source of neodymium that could have a significantly lower impact on the environment than current mining and extraction processes. Neodymium can be readily oxidized in the presence of oxygen, which makes it easy to recover neodymium in oxide form. Thermochemical data and phase diagrams for neodymium oxide containing systems is, however, very limited. Thermodynamic modeling of the B2O3-FeO-Fe2O3-Nd2O3 system was hence performed to obtain accurate phase diagrams and thermochemical properties of the system. Key phase diagram experiments were also carried out for the FeO-Nd2O3 system in saturation with iron to improve the accuracy of the present modeling. The modified quasichemical model was used to describe the Gibbs energy of the liquid oxide phase. The Gibbs energy functions of the liquid phase and the solids were optimized to reproduce all available and reliable phase diagram data, and thermochemical properties of the system. Finally the optimized database was applied to calculate conditions for selective oxidation of neodymium from NdFeB magnet waste.

  7. Li2b2-Façade: Simulation of i2b2 Data Warehouse Server and Client for Interaction with Other Systems.

    Science.gov (United States)

    Majeed, Raphael W; Xu, Tingyan; Stöhr, Mark R; Röhrig, Rainer

    2017-01-01

    Since its release in 2004, the i2b2 data warehouse software has become a valuable tool for clinical researchers. Physicians can use its browser-based query frontend intuitively without additional training or reading through documentation. While the i2b2 software describes it's API as "REST", it is neither stateless nor does it follow the common guidelines for RESTful APIs. Thus, interfacing other software with i2b2's custom RPC-style XML-API is a very cumbersome process. To overcome these issues, we developed a lightweight software abstraction layer "lightweight i2b2 façade" (li2b2-façade).

  8. Cosima B2B - Sales Automation for E-Procurement

    OpenAIRE

    Kießling, Werner (Prof. Dr.); Fischer, Stefan; Döring, Sven

    2006-01-01

    E-procurement is one of the fastest growing application areas for e-commerce. Though B2B transaction costs could be reduced recently by establishing XML based standards for electronic product catalogs and data interchange, B2B sales costs are still high due to the amount of human interaction. For the first time we present a fully automated electronic sales agent for e-procurement portals. The key technologies for this breakthrough are based on preferences modeled as strict partial orders, ena...

  9. NMR relaxation rates and Knight shifts in MgB2 and AlB2: theory versus experiments

    International Nuclear Information System (INIS)

    Pavarini, E; Baek, S H; Suh, B J; Borsa, F; Bud'ko, S L; Canfield, P C

    2003-01-01

    We have performed 11 B NMR measurements in 11 B enriched MgB 2 powder sample in the normal phase. The Knight shift was accurately determined by using the magic angle spinning technique. Results for 11 B and 27 Al Knight shifts (K) and relaxation rates (1/T 1 ) are also reported for AlB 2 . The data show a dramatic decrease of both K and 1/T 1 for 11 B in AlB 2 with respect to MgB 2 . We compare experimental results with ab initio calculated NMR relaxation rates and Knight shifts. The experimental values for 1/T 1 and K are in most cases in good agreement with the theoretical results. We show that the decrease of K and 1/T 1 for 11 B is consistent with a drastic drop of the density of states at the boron site in AlB 2 with respect to MgB 2

  10. Incidência de fumonisina B1, aflatoxinas B1, B2, G1 e G2, ocratoxina A e zearalenona em produtos de milho Occurrence of fumonisin B1, aflatoxins B1, B2, G1, and G2, ochratoxin A and zearalenone in corn products

    Directory of Open Access Journals (Sweden)

    Luciane Mie Kawashima

    2006-09-01

    Full Text Available Levantamentos de ocorrência de micotoxinas em alimentos foram realizados nas últimas duas décadas nas regiões Sudeste e Sul do Brasil. Levantamentos em alimentos comercializados em outras regiões têm-se limitado a aflatoxinas em amendoim e castanhas do Brasil. O presente trabalho pesquisou a presença de fumonisina B1, aflatoxinas B1, B2, G1 e G2, ocratoxina A e zearalenona em 74 amostras de produtos a base de milho adquiridas no comércio da cidade de Recife, PE, durante o período de 1999 a 2001. Fumonisina B1 foi determinada por cromatografia líquida de alta eficiência com detecção por fluorescência e as demais toxinas foram determinadas por cromatografia em camada delgada. Fumonisina B1 foi encontrada em 94,6% das amostras em concentrações variando de 20 a 8600 µg/kg. Apenas 5 amostras continham aflatoxina B1 e o teor máximo encontrado foi 20 µg/kg. Duas amostras ultrapassaram o limite de 20 µg/kg para a somatória das aflatoxinas B1, B2, G1 e G2 (farinha de milho pré-cozida com 21,5 µg/kg e quirera (xerém com 23,3 µg/kg. As aflatoxinas G1 e G2, ocratoxina A e zearalenona não foram detectadas em nenhuma das amostras. Todas as amostras contaminadas com aflatoxinas também apresentaram fumonisina B1.Research concerning the presence of mycotoxin in food has been conducted in the Southwest and South regions of Brazil over the last two decades. Research in other regions has been limited to aflatoxin in peanuts and Brazil nuts. The aim of this work is to study the presence of fumonisin B1, aflatoxins B1, B2, G1, and G2, ochratoxin A and zearalenone in 74 samples of corn products acquired in shops and food markets in the city of Recife (PE from 1999 to 2001. Fumonisin B1 was determined by high performance liquid chromatography and fluorescence was detected. The other toxins were determined by thin layer chromatography. Fumonisin B1 was found in 94.6% of the samples in levels from 20 to 8600 µg/kg. Only 5 samples contained

  11. The Chandra Source Catalog 2.0: Interfaces

    Science.gov (United States)

    D'Abrusco, Raffaele; Zografou, Panagoula; Tibbetts, Michael; Allen, Christopher E.; Anderson, Craig S.; Budynkiewicz, Jamie A.; Burke, Douglas; Chen, Judy C.; Civano, Francesca Maria; Doe, Stephen M.; Evans, Ian N.; Evans, Janet D.; Fabbiano, Giuseppina; Gibbs, Danny G., II; Glotfelty, Kenny J.; Graessle, Dale E.; Grier, John D.; Hain, Roger; Hall, Diane M.; Harbo, Peter N.; Houck, John C.; Lauer, Jennifer L.; Laurino, Omar; Lee, Nicholas P.; Martínez-Galarza, Rafael; McCollough, Michael L.; McDowell, Jonathan C.; Miller, Joseph; McLaughlin, Warren; Morgan, Douglas L.; Mossman, Amy E.; Nguyen, Dan T.; Nichols, Joy S.; Nowak, Michael A.; Paxson, Charles; Plummer, David A.; Primini, Francis Anthony; Rots, Arnold H.; Siemiginowska, Aneta; Sundheim, Beth A.; Van Stone, David W.

    2018-01-01

    Easy-to-use, powerful public interfaces to access the wealth of information contained in any modern, complex astronomical catalog are fundamental to encourage its usage. In this poster,I present the public interfaces of the second Chandra Source Catalog (CSC2). CSC2 is the most comprehensive catalog of X-ray sources detected by Chandra, thanks to the inclusion of Chandra observations public through the end of 2014 and to methodological advancements. CSC2 provides measured properties for a large number of sources that sample the X-ray sky at fainter levels than the previous versions of the CSC, thanks to the stacking of single overlapping observations within 1’ before source detection. Sources from stacks are then crossmatched, if multiple stacks cover the same area of the sky, to create a list of unique, optimal CSC2 sources. The properties of sources detected in each single stack and each single observation are also measured. The layered structure of the CSC2 catalog is mirrored in the organization of the CSC2 database, consisting of three tables containing all properties for the unique stacked sources (“Master Source”), single stack sources (“Stack Source”) and sources in any single observation (“Observation Source”). These tables contain estimates of the position, flags, extent, significances, fluxes, spectral properties and variability (and associated errors) for all classes of sources. The CSC2 also includes source region and full-field data products for all master sources, stack sources and observation sources: images, photon event lists, light curves and spectra.CSCview, the main interface to the CSC2 source properties and data products, is a GUI tool that allows to build queries based on the values of all properties contained in CSC2 tables, query the catalog, inspect the returned table of source properties, browse and download the associated data products. I will also introduce the suite of command-line interfaces to CSC2 that can be used in

  12. Circular dichroism beamline B23 at the Diamond Light Source.

    Science.gov (United States)

    Hussain, Rohanah; Jávorfi, Tamás; Siligardi, Giuliano

    2012-01-01

    Synchrotron radiation circular dichroism (SRCD) is a well established technique in structural biology. The first UV-VIS beamline, dedicated to circular dichroism, at Diamond Light Source Ltd, a third-generation synchrotron facility in south Oxfordshire, UK, has recently become operational and it is now available for the user community. Herein the main characteristics of the B23 SRCD beamline, the ancillary facilities available for users, and some of the recent advances achieved are summarized.

  13. Hydrothermal route to VO2 (B) nanorods: controlled synthesis and characterization

    Science.gov (United States)

    Song, Shaokun; Huang, Qiwei; Zhu, Wanting

    2017-10-01

    One-dimensional vanadium dioxides have attracted intensive attention owing to their distinctive structure and novel applications in catalysis, high energy lithium-ion batteries, chemical sensors/actuators and electrochemical devices etc. In this paper, large-scale VO2 (B) nanorods have been successfully synthesized via a versatile and environment friendly hydrothermal strategy using V2O5 as vanadium source and carbohydrates/alcohols as reductant. The obtained samples are characterized by XRD, FT-IR, TEM, and XPS techniques to investigate the effects of chemical parameters such as reductants, temperature, and time of synthesis on the structure and morphology of products. Results show that pure B phase VO2 with homogeneous nanorod-like morphology can be prepared easily at 180 °C for 3 days with glycerol as reluctant. Typically, the nanorod-like products are 0.5-1 μm long and 50 nm width. Furthermore, it is also confirmed that the products are consisted of VO2, corresponding to the B phase. More importantly, this novel approach is efficient, free of any harmful solvents and surfactants. Therefore, this efficient, green, and cost-saving route will have great potential in the large-scale fabrication of 1D VO2 (B) nanorods from the economic and environmental point of view.

  14. Competency-orientated brand cooperations of power supply companies in the B2B sector; Kompetenzorientierte Markenkooperationen von Energieversorgungsunternehmen im B2B-Kundenbereich

    Energy Technology Data Exchange (ETDEWEB)

    Peuser, M.M.

    2008-07-01

    On the basis of an extensive empirical study with B2B electricity users, the author of the book under consideration examines brand co-operations of power supply companies with companies not working in the area of energy production. Based on the view of various co-operation alternatives, impact relations and success-determining factors of influence in the area of B2B customers are identified. The term of the authority of an energy brand is discussed. Beside this, profiles of concrete brands of current power supply companies from the view of B2B customers are pointed out, and recommendations for the organization of brand co-operation and the structure of mark authority in practice are shown. This contribution is written for lecturers and students of the management economics with the emphasis of marketing and management as well as high-level personnel in the energy industry, who wants to develop strong mark authority by brand co-operation.

  15. Getting started with Oracle SOA B2B Integration a hands-on tutorial

    CERN Document Server

    Bhatia, Krishnaprem; Perlovsky, Alan

    2013-01-01

    This hands on tutorial gives you the best possible start you could hope for with Oracle B2B. Learn using real life scenarios and examples to give you a solid footing of B2B.This book is for B2B architects, consultants and developers who would like to design and develop B2B integrations using Oracle B2B. This book assumes no prior knowledge of Oracle B2B and explains all concepts from scratch using illustrations, real world examples and step-by-step instructions. The book covers enough depth and details to be useful for both beginner and advanced B2B users.

  16. Evolution, development, and communication of branding in B2B markets

    OpenAIRE

    Seyedghorban, Zahra

    2017-01-01

    While, branding was traditionally viewed as having limited significance in business-to-business (B2B) markets, existing research not only acknowledges its existence, but emphasises its strategic importance in enhancing organisations’ competitive positions and financial performance. Given the fragmented research on B2B branding, there is a need to first provide a comprehensive review of B2B branding literature as a field of study by conducting a bibliometric investigation (Essay 1). The result...

  17. Automated realtime data import for the i2b2 clinical data warehouse: introducing the HL7 ETL cell.

    Science.gov (United States)

    Majeed, Raphael W; Röhrig, Rainer

    2012-01-01

    Clinical data warehouses are used to consolidate all available clinical data from one or multiple organizations. They represent an important source for clinical research, quality management and controlling. Since its introduction, the data warehouse i2b2 gathered a large user base in the research community. Yet, little work has been done on the process of importing clinical data into data warehouses using existing standards. In this article, we present a novel approach of utilizing the clinical integration server as data source, commonly available in most hospitals. As information is transmitted through the integration server, the standardized HL7 message is immediately parsed and inserted into the data warehouse. Evaluation of import speeds suggest feasibility of the provided solution for real-time processing of HL7 messages. By using the presented approach of standardized data import, i2b2 can be used as a plug and play data warehouse, without the hurdle of customized import for every clinical information system or electronic medical record. The provided solution is available for download at http://sourceforge.net/projects/histream/.

  18. A Fast Healthcare Interoperability Resources (FHIR) layer implemented over i2b2.

    Science.gov (United States)

    Boussadi, Abdelali; Zapletal, Eric

    2017-08-14

    i2b2 model and the FHIR RM. To accomplish this, developers must manually browse the specifications of the FHIR standard. Our source code is freely available and can be adapted for use in other i2b2 sites.

  19. The role of electron heating physics in images and variability of the Galactic Centre black hole Sagittarius A*

    Science.gov (United States)

    Chael, Andrew; Rowan, Michael; Narayan, Ramesh; Johnson, Michael; Sironi, Lorenzo

    2018-05-01

    The accretion flow around the Galactic Centre black hole Sagittarius A* (Sgr A*) is expected to have an electron temperature that is distinct from the ion temperature, due to weak Coulomb coupling in the low-density plasma. We present four two-temperature general relativistic radiative magnetohydrodynamic (GRRMHD) simulations of Sgr A* performed with the code KORAL. These simulations use different electron heating prescriptions, motivated by different models of the underlying plasma microphysics. We compare the Landau-damped turbulent cascade model used in previous work with a new prescription we introduce based on the results of particle-in-cell simulations of magnetic reconnection. With the turbulent heating model, electrons are preferentially heated in the polar outflow, whereas with the reconnection model electrons are heated by nearly the same fraction everywhere in the accretion flow. The spectra of the two models are similar around the submillimetre synchrotron peak, but the models heated by magnetic reconnection produce variability more consistent with the level observed from Sgr A*. All models produce 230 GHz images with distinct black hole shadows which are consistent with the image size measured by the Event Horizon Telescope, but only the turbulent heating produces an anisotropic `disc-jet' structure where the image is dominated by a polar outflow or jet at frequencies below the synchrotron peak. None of our models can reproduce the observed radio spectral slope, the large near-infrared and X-ray flares, or the near-infrared spectral index, all of which suggest non-thermal electrons are needed to fully explain the emission from Sgr A*.

  20. B2B Models for DoD Acquisition

    National Research Council Canada - National Science Library

    Kamel, Magdi N

    2008-01-01

    A central vision of B2B e-commerce is that of an electronic marketplace that would bring suppliers together with major buyers of goods and services for the purpose of conducting "frictionless commerce...

  1. Agent-based services for B2B electronic commerce

    Science.gov (United States)

    Fong, Elizabeth; Ivezic, Nenad; Rhodes, Tom; Peng, Yun

    2000-12-01

    The potential of agent-based systems has not been realized yet, in part, because of the lack of understanding of how the agent technology supports industrial needs and emerging standards. The area of business-to-business electronic commerce (b2b e-commerce) is one of the most rapidly developing sectors of industry with huge impact on manufacturing practices. In this paper, we investigate the current state of agent technology and the feasibility of applying agent-based computing to b2b e-commerce in the circuit board manufacturing sector. We identify critical tasks and opportunities in the b2b e-commerce area where agent-based services can best be deployed. We describe an implemented agent-based prototype system to facilitate the bidding process for printed circuit board manufacturing and assembly. These activities are taking place within the Internet Commerce for Manufacturing (ICM) project, the NIST- sponsored project working with industry to create an environment where small manufacturers of mechanical and electronic components may participate competitively in virtual enterprises that manufacture printed circuit assemblies.

  2. Numerical simulations for the sources apportionment and control strategies of PM2.5 over Pearl River Delta, China, part I: Inventory and PM2.5 sources apportionment.

    Science.gov (United States)

    Huang, Yeqi; Deng, Tao; Li, Zhenning; Wang, Nan; Yin, Chanqin; Wang, Shiqiang; Fan, Shaojia

    2018-09-01

    This article uses the WRF-CMAQ model to systematically study the source apportionment of PM 2.5 under typical meteorological conditions in the dry season (November 2010) in the Pearl River Delta (PRD). According to the geographical location and the relative magnitude of pollutant emission, Guangdong Province is divided into eight subdomains for source apportionment study. The Brute-Force Method (BFM) method was implemented to simulate the contribution from different regions to the PM 2.5 pollution in the PRD. Results show that the industrial sources accounted for the largest proportion. For emission species, the total amount of NO x and VOC in Guangdong Province, and NH 3 and VOC in Hunan Province are relatively larger. In Guangdong Province, the emission of SO 2 , NO x and VOC in the PRD are relatively larger, and the NH 3 emissions are higher outside the PRD. In northerly-controlled episodes, model simulations demonstrate that local emissions are important for PM 2.5 pollution in Guangzhou and Foshan. Meanwhile, emissions from Dongguan and Huizhou (DH), and out of Guangdong Province (SW) are important contributors for PM 2.5 pollution in Guangzhou. For PM 2.5 pollution in Foshan, emissions in Guangzhou and DH are the major contributors. In addition, high contribution ratio from DH only occurs in severe pollution periods. In southerly-controlled episode, contribution from the southern PRD increases. Local emissions and emissions from Shenzhen, DH, Zhuhai-Jiangmen-Zhongshan (ZJZ) are the major contributors. Regional contribution to the chemical compositions of PM 2.5 indicates that the sources of chemical components are similar to those of PM 2.5 . In particular, SO 4 2- is mainly sourced from emissions out of Guangdong Province, while the NO 3- and NH 4+ are more linked to agricultural emissions. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. NuSTAR DISCOVERY OF A 3.76 s TRANSIENT MAGNETAR NEAR SAGITTARIUS A*

    DEFF Research Database (Denmark)

    Mori, Kaya; Gotthelf, Eric V.; Zhang, Shuo

    2013-01-01

    We report the discovery of 3.76 s pulsations from a new burst source near Sgr A* observed by the NuSTAR observatory. The strong signal from SGR J1745-29 presents a complex pulse profile modulated with pulsed fraction 27% +/- 3% in the 3-10 keV band. Two observations spaced nine days apart yield a......-ray band or have been detected as high-B radio pulsars. The peculiar location of SGR J1745-29 has important implications for the formation and dynamics of neutron stars in the Galactic center region....

  4. A PCV2 vaccine based on genotype 2b is more effective than a 2a-based vaccine to protect against PCV2b or combined PCV2a/2b viremia in pigs with concurrent PCV2, PRRSV and PPV infection.

    Science.gov (United States)

    Opriessnig, Tanja; O'Neill, Kevin; Gerber, Priscilla F; de Castro, Alessandra M M G; Gimenéz-Lirola, Luis G; Beach, Nathan M; Zhou, Lei; Meng, Xiang-Jin; Wang, Chong; Halbur, Patrick G

    2013-01-07

    The predominant genotype of porcine circovirus (PCV) in the pig population today is PCV2b yet PCV2a-based commercial vaccines are considered effective in protecting against porcine circovirus associated disease. The objective of this study was to compare the ability of PCV2a- and PCV2b-based vaccines to control PCV2b viremia in a challenge model that mimics the U.S. field situation. Sixty-three pigs were randomly assigned to one of eight groups. Sixteen pigs were vaccinated with an experimental live-attenuated chimeric PCV1-2a vaccine based on genotype 2a and another 16 pigs with a chimeric PCV1-2b vaccine based on genotype 2b. Challenge was done 28 days post vaccination (dpv) using PCV2b (or a combination of PCV2a and PCV2b), porcine reproductive and respiratory syndrome virus (PRRSV), and porcine parvovirus (PPV) to mimic what commonly occurs in the field. The experiment was terminated 21 days post challenge (dpc) or 49dpv. Pigs vaccinated with the chimeric PCV1-2b vaccine had significantly higher levels of PCV1-2b viremia and shedding of the PCV1-2b vaccine virus in feces and nasal secretions but also a more robust humoral immune response as evidenced by significantly higher ELISA S/P ratios compared to the PCV1-2a vaccination. Regardless of challenge, the PCV1-2b vaccination significantly reduced the prevalence and amount of PCV2 viremia compared to the PCV1-2a vaccination. Interestingly, in the non-vaccinated pigs concurrent PCV2a infection resulted in clinical disease and increased macroscopic lung lesions compared to pigs challenged with PCV2b alone, further supporting the idea that concurrent PCV2a/PCV2b infection is necessary for optimal PCV2 replication. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Effect of Mo/B atomic ratio on the properties of Mo2NiB2-based cermets

    International Nuclear Information System (INIS)

    Xie, Lang; Li, XiaoBo; Zhang, Dan; Yi, Li; Gao, XiaoQing; Xiangtan Univ.

    2015-01-01

    Using three elementary substances, Mo, Ni, and amorphous B as raw materials, four series of Mo 2 NiB 2 -based cermets with the Mo/B atomic ratio ranging from 0.9 to 1.2 were successfully prepared via reaction sintering. The effect of Mo/B atomic ratio on the microstructure and properties was studied for the cermets. The results indicate that there is a strong correlation between the Mo/B atomic ratio and properties. The transverse rupture strength of the cermets increases with an increase in Mo/B ratio and shows a maximum value of 1 872 MPa at an Mo/B atomic ratio of 1.1 and then decreases with increasing Mo/B atomic ratio. The hardness and the corrosion resistance of the cermets increase monotonically with an increase in Mo/B atomic ratio. In Mo-rich cermets with an atomic ratio of Mo/B above 1.1, a small amount Ni-Mo intermetallic compound is found precipitated at the interface of Mo 2 NiB 2 grains.

  6. Bismuth-boron multiple bonding in BiB{sub 2}O{sup -} and Bi{sub 2}B{sup -}

    Energy Technology Data Exchange (ETDEWEB)

    Jian, Tian; Cheung, Ling Fung; Chen, Teng-Teng; Wang, Lai-Sheng [Department of Chemistry, Brown University, Providence, RI (United States)

    2017-08-01

    Despite its electron deficiency, boron is versatile in forming multiple bonds. Transition-metal-boron double bonding is known, but boron-metal triple bonds have been elusive. Two bismuth boron cluster anions, BiB{sub 2}O{sup -} and Bi{sub 2}B{sup -}, containing triple and double B-Bi bonds are presented. The BiB{sub 2}O{sup -} and Bi{sub 2}B{sup -} clusters are produced by laser vaporization of a mixed B/Bi target and characterized by photoelectron spectroscopy and ab initio calculations. Well-resolved photoelectron spectra are obtained and interpreted with the help of ab initio calculations, which show that both species are linear. Chemical bonding analyses reveal that Bi forms triple and double bonds with boron in BiB{sub 2}O{sup -} ([Bi≡B-B≡O]{sup -}) and Bi{sub 2}B{sup -} ([Bi=B=Bi]{sup -}), respectively. The Bi-B double and triple bond strengths are calculated to be 3.21 and 4.70 eV, respectively. This is the first experimental observation of Bi-B double and triple bonds, opening the door to design main-group metal-boron complexes with multiple bonding. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Investigation on demagnetization of Nd2Fe14B permanent magnets induced by irradiation

    Science.gov (United States)

    Li, Zhefu; Jia, Yanyan; Liu, Renduo; Xu, Yuhai; Wang, Guanghong; Xia, Xiaobin

    2017-12-01

    Nd2Fe14B is an important component of insertion devices, which are used in synchrotron radiation sources, and could be demagnetized by irradiation. In the present study, the Monte Carlo code FLUKA was used to analyze the irradiation field of Nd2Fe14B, and it was confirmed that the main demagnetization particle was neutron. Nd2Fe14B permanent magnet samples were irradiated by Ar ions at different doses to simulate neutron irradiation damage. The hysteresis loops were measured using a vibrating sample magnetometer, and the microstructure evolutions were characterized by transmission electron microscopy. Moreover, the relationship between them was discussed. The results indicate that the decrease in saturated magnetization is caused by the changes in microstructure. The evolution of single crystals into an amorphous structure is the reason for the demagnetization phenomenon of Nd2Fe14B permanent magnets when considering its microscopic structure.

  8. Mushroom-free selective epitaxial growth of Si, SiGe and SiGe:B raised sources and drains

    Science.gov (United States)

    Hartmann, J. M.; Benevent, V.; Barnes, J. P.; Veillerot, M.; Lafond, D.; Damlencourt, J. F.; Morvan, S.; Prévitali, B.; Andrieu, F.; Loubet, N.; Dutartre, D.

    2013-05-01

    We have evaluated various Cyclic Selective Epitaxial Growth/Etch (CSEGE) processes in order to grow "mushroom-free" Si and SiGe:B Raised Sources and Drains (RSDs) on each side of ultra-short gate length Extra-Thin Silicon-On-Insulator (ET-SOI) transistors. The 750 °C, 20 Torr Si CSEGE process we have developed (5 chlorinated growth steps with four HCl etch steps in-between) yielded excellent crystalline quality, typically 18 nm thick Si RSDs. Growth was conformal along the Si3N4 sidewall spacers, without any poly-Si mushrooms on top of unprotected gates. We have then evaluated on blanket 300 mm Si(001) wafers the feasibility of a 650 °C, 20 Torr SiGe:B CSEGE process (5 chlorinated growth steps with four HCl etch steps in-between, as for Si). As expected, the deposited thickness decreased as the total HCl etch time increased. This came hands in hands with unforeseen (i) decrease of the mean Ge concentration (from 30% down to 26%) and (ii) increase of the substitutional B concentration (from 2 × 1020 cm-3 up to 3 × 1020 cm-3). They were due to fluctuations of the Ge concentration and of the atomic B concentration [B] in such layers (drop of the Ge% and increase of [B] at etch step locations). Such blanket layers were a bit rougher than layers grown using a single epitaxy step, but nevertheless of excellent crystalline quality. Transposition of our CSEGE process on patterned ET-SOI wafers did not yield the expected results. HCl etch steps indeed helped in partly or totally removing the poly-SiGe:B mushrooms on top of the gates. This was however at the expense of the crystalline quality and 2D nature of the ˜45 nm thick Si0.7Ge0.3:B recessed sources and drains selectively grown on each side of the imperfectly protected poly-Si gates. The only solution we have so far identified that yields a lesser amount of mushrooms while preserving the quality of the S/D is to increase the HCl flow during growth steps.

  9. Adhesive and Cohesive Strength in FeB/Fe2B Systems

    Science.gov (United States)

    Meneses-Amador, A.; Blancas-Pérez, D.; Corpus-Mejía, R.; Rodríguez-Castro, G. A.; Martínez-Trinidad, J.; Jiménez-Tinoco, L. F.

    2018-05-01

    In this work, FeB/Fe2B systems were evaluated by the scratch test. The powder-pack boriding process was performed on the surface of AISI M2 steel. The mechanical parameters, such as yield stress and Young's modulus of the boride layer, were obtained by the instrumented indentation technique. Residual stresses produced on the boride layer were estimated by using the x-ray diffraction (XRD) technique. The scratch test was performed in order to evaluate the cohesive/adhesive strength of the FeB/Fe2B coating. In addition, a numerical evaluation of the scratch test on boride layers was performed by the finite element method. Maximum principal stresses were related to the failure mechanisms observed by the experimental scratch test. Shear stresses at the interfaces of the FeB/Fe2B/substrate system were also evaluated. Finally, the results obtained provide essential information about the effect of the layer thickness, the residual stresses, and the resilience modulus on the cohesive/adhesive strength in FeB/Fe2B systems.

  10. Detection of Intrinsic Source Structure at ∼3 Schwarzschild Radii with Millimeter-VLBI Observations of SAGITTARIUS A*

    Science.gov (United States)

    Lu, Ru-Sen; Krichbaum, Thomas P.; Roy, Alan L.; Fish, Vincent L.; Doeleman, Sheperd S.; Johnson, Michael D.; Akiyama, Kazunori; Psaltis, Dimitrios; Alef, Walter; Asada, Keiichi; Beaudoin, Christopher; Bertarini, Alessandra; Blackburn, Lindy; Blundell, Ray; Bower, Geoffrey C.; Brinkerink, Christiaan; Broderick, Avery E.; Cappallo, Roger; Crew, Geoffrey B.; Dexter, Jason; Dexter, Matt; Falcke, Heino; Freund, Robert; Friberg, Per; Greer, Christopher H.; Gurwell, Mark A.; Ho, Paul T. P.; Honma, Mareki; Inoue, Makoto; Kim, Junhan; Lamb, James; Lindqvist, Michael; Macmahon, David; Marrone, Daniel P.; Martí-Vidal, Ivan; Menten, Karl M.; Moran, James M.; Nagar, Neil M.; Plambeck, Richard L.; Primiani, Rurik A.; Rogers, Alan E. E.; Ros, Eduardo; Rottmann, Helge; SooHoo, Jason; Spilker, Justin; Stone, Jordan; Strittmatter, Peter; Tilanus, Remo P. J.; Titus, Michael; Vertatschitsch, Laura; Wagner, Jan; Weintroub, Jonathan; Wright, Melvyn; Young, Ken H.; Zensus, J. Anton; Ziurys, Lucy M.

    2018-05-01

    We report results from very long baseline interferometric (VLBI) observations of the supermassive black hole in the Galactic center, Sgr A*, at 1.3 mm (230 GHz). The observations were performed in 2013 March using six VLBI stations in Hawaii, California, Arizona, and Chile. Compared to earlier observations, the addition of the APEX telescope in Chile almost doubles the longest baseline length in the array, provides additional uv coverage in the N–S direction, and leads to a spatial resolution of ∼30 μas (∼3 Schwarzschild radii) for Sgr A*. The source is detected even at the longest baselines with visibility amplitudes of ∼4%–13% of the total flux density. We argue that such flux densities cannot result from interstellar refractive scattering alone, but indicate the presence of compact intrinsic source structure on scales of ∼3 Schwarzschild radii. The measured nonzero closure phases rule out point-symmetric emission. We discuss our results in the context of simple geometric models that capture the basic characteristics and brightness distributions of disk- and jet-dominated models and show that both can reproduce the observed data. Common to these models are the brightness asymmetry, the orientation, and characteristic sizes, which are comparable to the expected size of the black hole shadow. Future 1.3 mm VLBI observations with an expanded array and better sensitivity will allow more detailed imaging of the horizon-scale structure and bear the potential for a deep insight into the physical processes at the black hole boundary.

  11. SIGMA/B, Doses in Space Vehicle for Multiple Trajectories, Various Radiation Source

    International Nuclear Information System (INIS)

    Jordan, T.M.

    2003-01-01

    1 - Description of problem or function: SIGMA/B calculates radiation dose at arbitrary points inside a space vehicle, taking into account vehicle geometry, heterogeneous placement of equipment and stores, vehicle materials, time-weighted astronaut positions and many radiation sources from mission trajectories, e.g. geomagnetically trapped protons and electrons, solar flare particles, galactic cosmic rays and their secondary radiations. The vehicle geometry, equipment and supplies, and man models are described by quadric surfaces. The irradiating flux field may be anisotropic. The code can be used to perform simultaneous dose calculations for multiple vehicle trajectories, each involving several radiation sources. Results are presented either as dose as a function of shield thickness, or the dose received through designated outer sections of the vehicle. 2 - Method of solution: Automatic sectoring of the vehicle is performed by a Simpson's rule integration over angle; the dose is computed by a numerical angular integration of the dose attenuation kernels about the dose points. The kernels are curve-fit functions constructed from input data tables. 3 - Restrictions on the complexity of the problem: The code uses variable dimensioning techniques to store data. The only restriction on problem size is the available core storage

  12. To be or not B2B?

    CERN Document Server

    Symons, L J

    2001-01-01

    La question du commerce électronique interentreprises par le web (Business to Business, B2B) est posée actuellement par les grands groupes industriels impliqués dans le commerce mondial. Les prévisions sont imposantes, le B2B atteindra le C.A. de 3000 milliards de dollars en 2003. Les conditions d'accès, la façon de procéder des deux organisateurs (ARIBA et COMMERCE ONE) des plus grandes places de marchés actuelles, sont décrites. La base de l'énorme pyramide est le catalogue électronique multilingue UNSPSC (United Nations Standard Products and Services Classification) et l'organisation ECCMA (Electronic Commerce Code Management Association) qui gère le développement des UNSPSC codes en 8 langues. Dans ce contexte, l'auteur (re)-déclare qu'un des efforts principaux à fournir par le CERN est la création de son propre catalogue électronique. Dans la Division ST, une aide partielle à ce vaste programme pourrait être apportée par la normalisation des codes et désignations des pièces de maint...

  13. Seasonal effect and source apportionment of polycyclic aromatic hydrocarbons in PM2.5

    Science.gov (United States)

    Khan, Md Firoz; Latif, Mohd Talib; Lim, Chee Hou; Amil, Norhaniza; Jaafar, Shoffian Amin; Dominick, Doreena; Mohd Nadzir, Mohd Shahrul; Sahani, Mazrura; Tahir, Norhayati Mohd

    2015-04-01

    This study aims to investigate distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) bound to fine particulate matter (PM2.5) captured in a semi-urban area in Malaysia during different seasons, and to assess their health risks. PM2.5 samples were collected using a high volume air sampler on quartz filter paper at a flow rate of 1 m3 min-1 for 24 h. PAHs on the filter paper were extracted with dichloromethane (DCM) using an ultrasonic centrifuge solid-phase extraction method and measured by gas chromatography-mass spectroscopy. The results showed that the range of PAHs concentrations in the study period was between 0.21 and 12.08 ng m-3. The concentrations of PAHs were higher during the south-west monsoon (0.21-12.08 ng m-3) compared to the north-east monsoon (0.68-3.80 ng m-3). The high molecular weight (HMW) PAHs (≥5 ring) are significantly prominent (>70%) compared to the low molecular weight (LMW) PAHs (≤4 ring) in PM2.5. The Spearman correlation indicates that the LMW and HMW PAHs correlate strongly among themselves. The diagnostic ratios (DRs) of I[c]P/I[c]P + BgP and B[a]P/B[g]P suggest that the HMW PAHs originated from fuel combustion sources. The source apportionment analysis of PAHs was resolved using DRs-positive matrix factorization (PMF)-multiple linear regression (MLR). The main sources identified were (a) gasoline combustion (65%), (b) diesel and heavy oil combustion (19%) and (c) natural gas and coal burning (15%). The health risk evaluation, by means of the lifetime lung cancer risk (LLCR), showed no potential carcinogenic risk from the airborne BaPeq (which represents total PAHs at the present study area in Malaysia). The seasonal LLCR showed that the carcinogenic risk of total PAHs were two fold higher during south-westerly monsoon compared to north-easterly monsoon.

  14. Beyond the exchange--the future of B2B.

    Science.gov (United States)

    Wise, R; Morrison, D

    2000-01-01

    Using the Internet to facilitate business-to-business commerce promises many benefits, such as dramatic cost reductions and greater access to buyers and sellers. Yet little is known about how B2B e-commerce will evolve. The authors argue that changes in the financial services industry over the past two decades provide important clues. Exchanges, they say, are not the primary source of value in information-intensive markets; value tends to accumulate among a diverse group of specialists that focus on such tasks as packaging, standard setting, arbitrage, and information management. Because scale and liquidity are vitally important to efficient trading, today's exchanges will consolidate into a relatively small set of mega-exchanges. Originators will handle the origination and aggregation of complex transactions before sending them on to mega-exchanges for execution. E-speculators, seeking to capitalize on an abundance of market information, will tend to concentrate where relatively standardized products can be transferred easily among a large group of buyers. In many markets, a handful of independent solution providers with well-known brand names and solid reputations will thrive alongside mega-exchanges. Sell-side asset exchanges will create the networks and provide the tools to allow suppliers to trade orders among themselves, sometimes after initial transactions with customers are made on the mega-exchanges. For many companies, traditional skills in such areas as product development, manufacturing, and marketing may become relatively less important, while the ability to understand and capitalize on market dynamics may become considerably more important.

  15. Exposure assessment to fumonisins B1, B2 and B3 through consumption of gluten-free foodstuffs intended for people affected by celiac disease.

    Science.gov (United States)

    Esposito, Francesco; Fasano, Evelina; Scognamiglio, Gelsomina; Nardone, Antonio; Triassi, Maria; Cirillo, Teresa

    2016-11-01

    Fumonisins are mycotoxins produced by Fusarium species and affecting maize crops. Some analogues of fumonisins are known for their toxic and possible carcinogenic effects on humans and animals. Because of their occurrence in corn-based food, diet is the main source of exposure to these mycotoxins, especially among people affected by celiac disease. Hence, the purpose of this paper was to evaluate the amount of fumonisins B1, B2 and B3 in maize-based products and to assess the exposure of people affected by celiac disease to fumonisins. The sample consisted of 154 gluten-free products analyzed according to method UNI EN 14352:2005. Results showed a heterogeneous contamination by fumoninisin B1, B2 and B3, although below limits of Commission Regulation No 1126/2007 and consistent with other European literature data. Exposure to fumonisins was evaluated for different age groups. In some cases exposure to fumonisins could not be ignored since the total intake could exceed EFSA Provisional Maximum Tolerable Intake up to 150%. Therefore, in the light of an overall contamination by fumonisins the total dietary exposure could be underrated not only in people affected by celiac disease, but also in non-celiac population. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. The effect of citric and oxalic acid doping on the superconducting properties of MgB2

    International Nuclear Information System (INIS)

    Ojha, N; Singla, Rashmi; Varma, G D; Malik, V K; Bernhard, C

    2009-01-01

    In this paper we report the effect of carbon doping on the structural and superconducting properties of MgB 2 using citric and oxalic acids as carbon sources. The bulk polycrystalline samples have been synthesized via a standard solid state reaction route with composition MgB 2 +x wt% of citric and oxalic acids (x = 0, 5 and 10). The x-ray diffraction results reveal the formation of dominantly MgB 2 with only a small amount of impurity phase MgO and substitution of C at the B site of MgB 2 for both dopants. Improvements in the upper critical field (H C2 ), irreversibility field (H irr ) and high field (>2.5 T) critical current density (J C ) have been observed on C doping in the samples. The correlations between superconducting properties and structural characteristics of the samples are described and discussed in this paper.

  17. In vitro study of vitamins B1, B2 and B6 adsorption on zeolite

    Directory of Open Access Journals (Sweden)

    Basić Zorica

    2011-01-01

    Full Text Available Background/Aim. Zeolites are the hydratised alumosilicates of alcali and earthalcali cations, which have a long three-dimensional crystal structure. Preparations on the basis of zeolites are used for adsorption of organic and nonorganic toxic substances and they, also, find more and more use in veterinary and human medicine and pharmacy. The aim of this study was to evaluate the possibilities of zeolite to adsorb vitamins B1, B2 and B6 in acid and neutral solutions, as well as the characteristics of the process (saturability, reversibility and competitivness. Methods. The specific and sensitive HPLC method with fluorescent detector was used for determination of vitamins B1, B2 and B6. Analyte separation and detection were carried out by applying the reverse-phase method on column C18. An in vitro experiment was done by testing the influence of pH value (2 and 7, concentration of vitamin solution (1, 2 and 5 mg/L, the lenght of contact with zeolite (10-180 min and cation competitiveness on the exchange capacity, which is achieved by media and zeolite contact, as well as a possible vitamins desorption through changing pH value of the solution at 37°C. Jon competitiveness was examined by adding commercial feed mixture (grower with a defined content of the examined vitamines in zeolite solutions the pH = 2 and pH = 7. Results. Vitamins B1, B2 and B6 were stable in both pH=2 and pH = 7 solutions at 37°C, in the defined time intervals. In acid solution concentrations of vitamins significantly declined in the first 10 min, with no significant decline in further 30 min for all the three concentrations testch. In neutral solution, after the addition of 1% zeolite, decrease in vitamins concentrations was slightly lower than in acid solution, but also significant in the first 10 min of the contact with zeolite. It was found that zeolite, which adsorbed vitamins in acid solution, transferred in the neutral one released a significant quantity of adsorbed

  18. CHEMICAL SIMULATIONS OF PREBIOTIC MOLECULES: INTERSTELLAR ETHANIMINE ISOMERS

    Energy Technology Data Exchange (ETDEWEB)

    Quan, Donghui; Durr, Allison [Department of Chemistry, Eastern Kentucky University, Richmond, KY 40475 (United States); Herbst, Eric [Departments of Chemistry and Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Corby, Joanna F. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Hassel, George [Physics and Astronomy Department, Siena College, Loudonville, NY 12211 (United States)

    2016-06-20

    The E- and Z- isomers of ethanimine (CH{sub 3}CHNH) were recently detected toward the star-forming region Sagittarius (Sgr) B2(N) using the Green Bank Telescope PRIMOS cm-wave spectral data, and imaged by the Australia Telescope Compact Array. Ethanimine is not reported in the hot cores of Sgr B2, but only in gas that absorbs at +64 and +82 km s{sup −1} in the foreground of continuum emission generated by H ii regions. The ethanimine isomers can serve as precursors of the amino acid alanine and may play important roles in forming biological molecules in the interstellar medium. Here we present a study of the chemistry of ethanimine using a gas-grain simulation based on rate equations, with both isothermal and warm-up conditions. In addition, the density, kinetic temperature, and cosmic ray ionization rate have been varied. For a variety of physical conditions in the warm-up models for Sgr B2(N) and environs, the simulations show reasonable agreement with observationally obtained abundances. Isothermal models of translucent clouds along the same line of sight yield much lower abundances, so that ethanimine would be much more difficult to detect in these sources despite the fact that other complex molecules have been detected there.

  19. Chemical Simulations of Prebiotic Molecules: Interstellar Ethanimine Isomers

    Science.gov (United States)

    Quan, Donghui; Herbst, Eric; Corby, Joanna F.; Durr, Allison; Hassel, George

    2016-06-01

    The E- and Z-isomers of ethanimine (CH3CHNH) were recently detected toward the star-forming region Sagittarius (Sgr) B2(N) using the Green Bank Telescope PRIMOS cm-wave spectral data, and imaged by the Australia Telescope Compact Array. Ethanimine is not reported in the hot cores of Sgr B2, but only in gas that absorbs at +64 and +82 km s-1 in the foreground of continuum emission generated by H II regions. The ethanimine isomers can serve as precursors of the amino acid alanine and may play important roles in forming biological molecules in the interstellar medium. Here we present a study of the chemistry of ethanimine using a gas-grain simulation based on rate equations, with both isothermal and warm-up conditions. In addition, the density, kinetic temperature, and cosmic ray ionization rate have been varied. For a variety of physical conditions in the warm-up models for Sgr B2(N) and environs, the simulations show reasonable agreement with observationally obtained abundances. Isothermal models of translucent clouds along the same line of sight yield much lower abundances, so that ethanimine would be much more difficult to detect in these sources despite the fact that other complex molecules have been detected there.

  20. Creating Competitive Advantage by Rethinking B2B Software Pricing

    OpenAIRE

    Adelstrand, Carl; Brostedt, Emil

    2016-01-01

    The choice of pricing model for software products is a complex procedure due to the different characteristics compared to physical products. This thesis investigates and compares software pricing models in a B2B setting, and describes how KAM plays a role in executing a pricing model. The research has been conducted as an opportunist case study on Adebro, a technology company in the B2B sector. The thesis have come to the following conclusions, with data from interviews and literature: Perpet...

  1. 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.

  2. Mission and Sustainability of Informatics for Integrating Biology and the Bedside (i2b2).

    Science.gov (United States)

    Murphy, Shawn; Wilcox, Adam

    2014-01-01

    A visible example of a successfully disseminated research project in the healthcare space is Informatics for Integrating Biology and the Bedside, or i2b2. The project serves to provide the software that can allow a researcher to do direct, self-serve queries against the electronic healthcare data form a hospital. The goals of these queries are to find cohorts of patients that fit specific profiles, while providing for patient privacy and discretion. Sustaining this resource and keeping its direction has always been a challenge, but ever more so as the ten year National Centers for Biomedical Computing (NCBCs) sunset their funding. Building on the i2b2 structures has helped the dissemination plans for grants leveraging it because it is a disseminated national resource. While this has not directly increased the support of i2b2 internally, it has increased the ability of institutions to leverage the resource and generally leads to increased institutional support. The successful development, use, and dissemination i2b2 has been significant in clinical research and informatics. Its evolution has been from a local research data infrastructure to one disseminated more broadly than any other product of the National Centers for Biomedical Computing, and an infrastructure spawning larger investments than were originally used to create it. Throughout this, there were two main lessons about the benefits of dissemination: that people have great creativity in utilizing a resource in different ways and that broader system use can make the system more robust. One option for long-term sustainability of the central authority would be to translate the function to an industry partner. Another option currently being pursued is to create a foundation that would be a central authority for the project. Over the past 10 years, i2b2 has risen to be an important staple in the toolkit of health care researchers. There are now over 110 hospitals that use i2b2 for research. This open-source

  3. Heat shock factors HsfB1 and HsfB2b are involved in the regulation of Pdf1.2 expression and pathogen resistance in Arabidopsis.

    Science.gov (United States)

    Kumar, Mukesh; Busch, Wolfgang; Birke, Hannah; Kemmerling, Birgit; Nürnberger, Thorsten; Schöffl, Friedrich

    2009-01-01

    In order to assess the functional roles of heat stress-induced class B-heat shock factors in Arabidopsis, we investigated T-DNA knockout mutants of AtHsfB1 and AtHsfB2b. Micorarray analysis of double knockout hsfB1/hsfB2b plants revealed as strong an up-regulation of the basal mRNA-levels of the defensin genes Pdf1.2a/b in mutant plants. The Pdf expression was further enhanced by jasmonic acid treatment or infection with the necrotrophic fungus Alternaria brassicicola. The single mutant hsfB2b and the double mutant hsfB1/B2b were significantly improved in disease resistance after A. brassicicola infection. There was no indication for a direct interaction of Hsf with the promoter of Pdf1.2, which is devoid of perfect HSE consensus Hsf-binding sequences. However, changes in the formation of late HsfA2-dependent HSE binding were detected in hsfB1/B2b plants. This suggests that HsfB1/B2b may interact with class A-Hsf in regulating the shut-off of the heat shock response. The identification of Pdf genes as targets of Hsf-dependent negative regulation is the first evidence for an interconnection of Hsf in the regulation of biotic and abiotic responses.

  4. Assessment of liquid hydrogen cooled MgB2 conductors for magnetically confined fusion

    International Nuclear Information System (INIS)

    Glowacki, B A; Nuttall, W J

    2008-01-01

    Importantly environmental factors are not the only policy-driver for the hydrogen economy. Over the timescale of the development of fusion energy systems, energy security issues are likely to motivate a shift towards both hydrogen production and fusion as an energy source. These technologies combine local control of the system with the collaborative research interests of the major energy users in the global economy. A concept Fusion Island Reactor that might be used to generate H 2 (rather than electricity) is presented. Exploitation of produced hydrogen as a coolant and as a fuel is proposed in conjunction with MgB 2 conductors for the tokomak magnets windings, and electrotechnical devices for Fusion Island's infrastructure. The benefits of using MgB 2 over the Nb-based conductors during construction, operation and decommissioning of the Fusion Island Reactor are presented. The comparison of Nb 3 Sn strands for ITER fusion magnet with newly developed high field composite MgB 2 PIT conductors has shown that at 14 Tesla MgB 2 possesses better properties than any of the Nb 3 Sn conductors produced. In this paper the potential of MgB 2 conductors is examined for tokamaks of both the conventional ITER type and a Spherical Tokamak geometry. In each case MgB 2 is considered as a conductor for a range of field coil applications and the potential for operation at both liquid helium and liquid hydrogen temperatures is considered. Further research plans concerning the application of MgB 2 conductors for Fusion Island are also considered

  5. How has IT impacted the B2B sales process?

    OpenAIRE

    Bjørnstad, Julia Jemli

    2017-01-01

    B2B sales role plays a major role in driving the economy, and this industry has been experiencing major changes over the year with the advances in technology which allow for more cost savings and driving for more efficient ways of conducting sales operations. The objective of this exploratory qualitative research paper was to raise interest in the role technology plays in the B2B sales process today from the salesperson’s view point. It was further partly built on previous rese...

  6. B2B-uutiskirjeen visuaalisen ilmeen kehitys — Case Tamtron Solutions Oy

    OpenAIRE

    Salo, Sari

    2014-01-01

    Opinnäytetyön tarkoituksena oli kehittää Tamtron Solutions Oy:n uutiskirjeelle uusi visuaalinen ilme. Yrityksen lähettämästä uutiskirjeestä yritysasiakkaille puhutaan B2B-uutiskirjeenä. Tamtron Solutions Oy halusi B2B-uutiskirjeen avulla tehostaa markkinointia, kasvattaa myyntiä ja luoda uusia asiakassuhteita. Yritys halusi toteuttaa markkinointikampanjan B2B-uutiskirjeen muodossa rakennusalan yrityksille. Yritys valitsi kampanjan kohderyhmäksi rakennusalan yritykset, koska lakimuutos rakennu...

  7. The potential role of myocardial serotonin receptor 2B expression in canine dilated cardiomyopathy.

    Science.gov (United States)

    Fonfara, Sonja; Hetzel, Udo; Oyama, Mark A; Kipar, Anja

    2014-03-01

    Serotonin signalling in the heart is mediated by receptor subtype 2B (5-HTR2B). A contribution of serotonin to valvular disease has been reported, but myocardial expression of 5-HTR2B and its role in canine dilated cardiomyopathy (DCM) is not known. The aim of the present study was to investigate myocardial 5-HTR2B mRNA expression in dogs with DCM and to correlate results with expression of markers for inflammation and remodelling. Myocardial samples from eight healthy dogs, four dogs with DCM, five with cardiac diseases other than DCM and six with systemic non-cardiac diseases were investigated for 5-HTR2B mRNA expression using quantitative PCR (qPCR). The results were compared to mRNA expression of selected cytokines, matrix metalloproteinases (MMP) and tissue inhibitors of matrix metalloproteinase (TIMP). Laser microdissection with subsequent qPCR and immunohistochemistry were employed to identify the cells expressing 5-HTR2B. The myocardium of control dogs showed constitutive 5-HTR2B mRNA expression. In dogs with DCM, 5-HTR2B mRNA values were significantly greater than in all other groups, with highest levels of expression in the left ventricle and right atrium. Myocytes were identified as the source of 5-HTR2B mRNA and protein. A significant positive correlation of 5-HTR2B mRNA with expression of several cytokines, MMPs and TIMPs was observed. The findings suggest that serotonin might play a role in normal cardiac structure and function and could contribute to myocardial remodelling and functional impairment in dogs with DCM. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Search for atmospheric muon-neutrinos and extraterrestric neutrino point sources in the 1997 AMANDA-B10 data

    International Nuclear Information System (INIS)

    Biron von Curland, A.

    2002-07-01

    The young field of high energy neutrino astronomy can be motivated by the search for the origin of the charged cosmic rays. Large astrophysical objects like AGNs or supernova remnants are candidates to accelerate hadrons which then can interact to eventually produce high energy neutrinos. Neutrino-induced muons can be detected via their emission of Cherenkov light in large neutrino telescopes like AMANDA. More than 10 9 atmospheric muon events and approximately 5000 atmospheric neutrino events were registered by AMANDA-B10 in 1997. Out of these, 223 atmospheric neutrino candidate events have been extracted. This data set contains approximately 15 background events. It allows to confirm the expected sensitivity of the detector towards neutrino events. A second set containing 369 (approximately 270 atmospheric neutrino events and 100 atmospheric muon events) was used to search for extraterrestrial neutrino point sources. Neither a binned search, nor a cluster search, nor a search for preselected sources gave indications for the existence of a strong neutrino point source. Based on this result, flux limits were derived. Assuming E ν -2 spectra, typical flux limits for selected sources of the order of Φ μ limit ∝ 10 -14 cm -2 s -1 for muons and Φ ν limit ∝ 10 -7 cm -2 s -1 for neutrinos have been obtained. (orig.)

  9. Magnetic and Moessbauer studies on GdCo3B2 and DyCo3B2

    International Nuclear Information System (INIS)

    Malik, S.K.; Umarji, A.M.; Shenoy, G.K.

    1984-10-01

    Magnetization and Moessbauer studies have been carried out on GdCo 3 B 2 and DyCo 3 B 2 . These compounds are magnetically ordered with Curie temperatures of 56 0 and 21 0 K respectively. The Co atoms are either nonmagnetic or carry a small moment in these compounds. The saturation moment of DyCo 3 B 2 at 5 0 K is smaller than the Dy 3+ free-ion value. From 161 Dy Moessbauer studies, the measured hyperfine magnetic field at the Dy site is also observed to be smaller than the free-ion value. 155 Gd Moessbauer measurements in GdCo 3 B 2 reveal the presence of large crystalline electric fields at the rare earth site. This causes the moment and the hyperfine field at the Dy site in DyCo 3 B 2 to be reduced from its free-ion value

  10. B2B-verkkokaupan markkinointiviestintäsuunnitelma

    OpenAIRE

    Luoma, Hanna

    2015-01-01

    Opinnäytetyön aiheena oli luoda markkinointiviestintäsuunnitelma Yritys Oy:n kehitteillä olevalle verkkokaupalle. Työn tavoitteena oli markkinointiviestintäsuunnitelman avulla selvittää miten Yritys Oy:n B2B-verkkokauppa saadaan osaksi myyntitoimia ja miten se mahdollisimman tehokkaasti tuodaan asiakkaiden tietoisuuteen. Yritys Oy on vuonna 2003 perustettu perheyritys, jonka toiminta on kiinnitystekniikan tukkumyynti alan ammattilaisille. Yritys Oy:llä on useampi toimipiste ympäri Suomea...

  11. Biostimulation of anaerobic BTEX biodegradation under fermentative methanogenic conditions at source-zone groundwater contaminated with a biodiesel blend (B20).

    Science.gov (United States)

    Ramos, Débora Toledo; da Silva, Márcio Luis Busi; Chiaranda, Helen Simone; Alvarez, Pedro J J; Corseuil, Henry Xavier

    2013-06-01

    Field experiments were conducted to assess the potential for anaerobic biostimulation to enhance BTEX biodegradation under fermentative methanogenic conditions in groundwater impacted by a biodiesel blend (B20, consisting of 20 % v/v biodiesel and 80 % v/v diesel). B20 (100 L) was released at each of two plots through an area of 1 m(2) that was excavated down to the water table, 1.6 m below ground surface. One release was biostimulated with ammonium acetate, which was added weekly through injection wells near the source zone over 15 months. The other release was not biostimulated and served as a baseline control simulating natural attenuation. Ammonium acetate addition stimulated the development of strongly anaerobic conditions, as indicated by near-saturation methane concentrations. BTEX removal began within 8 months in the biostimulated source zone, but not in the natural attenuation control, where BTEX concentrations were still increasing (due to source dissolution) 2 years after the release. Phylogenetic analysis using quantitative PCR indicated an increase in concentration and relative abundance of Archaea (Crenarchaeota and Euryarchaeota), Geobacteraceae (Geobacter and Pelobacter spp.) and sulfate-reducing bacteria (Desulfovibrio, Desulfomicrobium, Desulfuromusa, and Desulfuromonas) in the biostimulated plot relative to the control. Apparently, biostimulation fortuitously enhanced the growth of putative anaerobic BTEX degraders and associated commensal microorganisms that consume acetate and H2, and enhance the thermodynamic feasibility of BTEX fermentation. This is the first field study to suggest that anaerobic-methanogenic biostimulation could enhance source zone bioremediation of groundwater aquifers impacted by biodiesel blends.

  12. Adoption of the B2SAFE EUDAT replication service by the EPOS community

    Science.gov (United States)

    Cacciari, Claudio; Fares, Massimo; Fiameni, Giuseppe; Michelini, Alberto; Danecek, Peter; Wittenburg, Peter

    2014-05-01

    B2SAFE is the EUDAT service for moving and replicating data between sites and storage systems for different purposes. The goal of B2SAFE is to keep the data from a repository safe by replicating it across different geographical and administrative zones according to a set of well-defined policies. It is also a way to store large volumes of data permanently at those sites which are providing powerful on-demand data analysis facilities. In particular, B2SAFE operates on the domain of registered data where data objects are referable via persistent identifiers (PIDs). B2SAFE is more than just copying data because the PIDs must be carefully managed when data objects are moved or replicated. The EUDAT B2SAFE Service offers functionality to replicate datasets across different data centres in a safe and efficient way while maintaining all information required to easily find and query information about the replica locations. The information about the replica locations and other important information is stored in PID records, each managed in separate administrative domains. The B2SAFE Service is implemented as an iRODS module providing a set of iRODS rules or policies to interface with the EPIC handle API and uses the iRODS middleware to replicate datasets from a source data (or community) centre to a destination data centre. The definition of the dataset(s) to replicate is flexible and up to the communities using the B2SAFE service. While the B2SAFE is internally using the EPIC handle API, communities have the choice to use any PID system they prefer to assign PIDs to their digital objects. A reference to one or more EUDAT B2SAFE PIDs is returned by the B2SAFE service when a dataset is replicated. The presentation will introduce the problem space of B2SAFE, presents the achievements that have been made during the last year for enabling communities to make use of the B2SAFE service, demonstrates a EPOS use cases, outlines the commonalities and differences between the policies

  13. A Clinical Data Warehouse Based on OMOP and i2b2 for Austrian Health Claims Data.

    Science.gov (United States)

    Rinner, Christoph; Gezgin, Deniz; Wendl, Christopher; Gall, Walter

    2018-01-01

    To develop simulation models for healthcare related questions clinical data can be reused. Develop a clinical data warehouse to harmonize different data sources in a standardized manner and get a reproducible interface for clinical data reuse. The Kimball life cycle for the development of data warehouse was used. The development is split into the technical, the data and the business intelligence pathway. Sample data was persisted in the Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM). The i2b2 clinical data warehouse tools were used to query the OMOP CDM by applying the new i2b2 multi-fact table feature. A clinical data warehouse was set up and sample data, data dimensions and ontologies for Austrian health claims data were created. The ability of the standardized data access layer to create and apply simulation models will be evaluated next.

  14. Ball-milling and AlB2 addition effects on the hydrogen sorption properties of the CaH2 + MgB2 system

    International Nuclear Information System (INIS)

    Schiavo, B.; Girella, A.; Agresti, F.; Capurso, G.; Milanese, C.

    2011-01-01

    Research highlights: → Calcium hydride + magnesium-aluminum borides as candidates for hydrogen storage. → Long time ball milling improves hydrogen sorption kinetics of the CaH 2 +MgB 2 system. → Coexistence of MgB 2 and AlB 2 does not improve hydrogen sorption performances. → Total substitution of MgB 2 with AlB 2 improves the system kinetics and reversibility. → Below 400 deg. C almost the full hydrogen capacity of the CaH 2 + AlB 2 system is reached. - Abstract: Among the borohydrides proposed for solid state hydrogen storage, Ca(BH 4 ) 2 is particularly interesting because of its favourable thermodynamics and relatively cheap price. Composite systems, where other species are present in addition to the borohydride, show some advantages in hydrogen sorption properties with respect to the borohydrides alone, despite a reduction of the theoretical storage capacity. We have investigated the milling time influence on the sorption properties of the CaH 2 + MgB 2 system from which Ca(BH 4 ) 2 and MgH 2 can be synthesized by hydrogen absorption process. Manometric and calorimetric measurements showed better kinetics for long time milled samples. We found that the total substitution of MgB 2 with AlB 2 in the starting material can improve the sorption properties significantly, while the co-existence of both magnesium and aluminum borides in the starting mixture did not cause any improvement. Rietveld refinements of the X-ray powder diffraction spectra were used to confirm the hypothesized reactions.

  15. On the critical success factors for B2B e-marketplace

    Directory of Open Access Journals (Sweden)

    Sareh Ahmad Khan Beige

    2015-01-01

    Full Text Available Advancement of network technology, quick growth of Internet and Internet based solutions lead many firms to apply online processes as well as electronic businesses. Internet based B2B E-C requires applying Internet and affiliated technologies for exchanging products, services and information. Implementation of business to business (B2B requires long-term commitment of organizations. Carrying out research in this field is regarded as very important issue for recognizing effective factors on successful implementation and execution of B2B and determining current status of organization. This research deals with studying effective critical factors on successful implementation and execution of B2B. Factors are recognized through studying literature review and IT experts. Then, through case study (studying a vehicle manufacturing firm and by using analytical network process (ANP, the importance of factor and their rank are determined. The factors that are regarded at this research are including: culture, commitment and support of senior management, government support, purposes, organizational strategies, trust, partial advantage and technical infrastructure. Results of research show that support and commitment of senior management are the highest priority factors.

  16. Automated population of an i2b2 clinical data warehouse from an openEHR-based data repository.

    Science.gov (United States)

    Haarbrandt, Birger; Tute, Erik; Marschollek, Michael

    2016-10-01

    Detailed Clinical Model (DCM) approaches have recently seen wider adoption. More specifically, openEHR-based application systems are now used in production in several countries, serving diverse fields of application such as health information exchange, clinical registries and electronic medical record systems. However, approaches to efficiently provide openEHR data to researchers for secondary use have not yet been investigated or established. We developed an approach to automatically load openEHR data instances into the open source clinical data warehouse i2b2. We evaluated query capabilities and the performance of this approach in the context of the Hanover Medical School Translational Research Framework (HaMSTR), an openEHR-based data repository. Automated creation of i2b2 ontologies from archetypes and templates and the integration of openEHR data instances from 903 patients of a paediatric intensive care unit has been achieved. In total, it took an average of ∼2527s to create 2.311.624 facts from 141.917 XML documents. Using the imported data, we conducted sample queries to compare the performance with two openEHR systems and to investigate if this representation of data is feasible to support cohort identification and record level data extraction. We found the automated population of an i2b2 clinical data warehouse to be a feasible approach to make openEHR data instances available for secondary use. Such an approach can facilitate timely provision of clinical data to researchers. It complements analytics based on the Archetype Query Language by allowing querying on both, legacy clinical data sources and openEHR data instances at the same time and by providing an easy-to-use query interface. However, due to different levels of expressiveness in the data models, not all semantics could be preserved during the ETL process. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Usability perspective on social media sites' adoption in the B2B context

    OpenAIRE

    Lacka, Ewelina; Chong, Alain

    2016-01-01

    While social media sites have been successfully adopted and used in the B2C context, they are perceived to be irrelevant in B2B marketing. This is due to marketers' perception of poor usability of these sites in the B2B sector. This study investigates the usability of social media sites when adopted for B2B marketing purposes in the one of world's largest social media market: China. Specifically, by extending the Technology Acceptance Model with Nielsen's Model of Attributes of System Accepta...

  18. USING UML SCENARIOS IN B2B SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. Jakimi

    2010-05-01

    Full Text Available Scenarios has become a popular technique for requirements elicitation and specification building. Since scenarios capture only partial descriptions of the system behavior, an approach for scenario composition and/or integration is needed to produce more complete specifications. The Unified Modeling Language (UML, which has become a standard notation for object-oriented modeling, provides a suitable framework for scenario acquisition using Use Case diagrams and Sequence or Collaboration diagrams. In this paper, we suggest an algorithmic and tool support for composing and integrating scenarios that are represented in form of sequence diagrams. We suggest four operators (;: sequential operator, ||: concurrent operator, ?: conditional operator and  * :iteration operator to compose a set of scenarios that describe a use case of a given system. In this paper, we suggest also to apply the scenario approach to B2B systems (Business to Business. We propose to develop B2B systems as a three activities process deriving formal specifications and code skeletons from UML scenarios. Activities of this proposed process are generally automatic and are supported by a set of developed algorithms and tools.

  19. Polymorphisms of cytochrome P450 2B6 (CYP2B6) in cynomolgus and rhesus macaques.

    Science.gov (United States)

    Uno, Yasuhiro; Uehara, Shotaro; Yamazaki, Hiroshi

    2018-02-22

    Cytochrome P450 2B6 (CYP2B6) is an important drug-metabolizing enzyme and is expressed in liver. Although human CYP2B6 variants account for variable enzyme properties among individuals and populations, CYP2B6 genetic variants have not been investigated in cynomolgus macaques, widely used in drug metabolism studies. CYP2B6 was resequenced in 120 cynomolgus macaques and 23 rhesus macaques by direct sequencing. Twenty-three non-synonymous variants were found, of which 12 and 3 were unique to cynomolgus macaques and rhesus macaques, respectively. By functional characterization using the 14 variant proteins, 8 variants (V114I, R253C, M435I, V459M, L465P, C475S, R487C, and R487H) showed different rate (>1.5-fold) of testosterone 16β-hydroxylation to wild type. However, the four variants (M435I, L465P, C475S, and R487H) were analyzed in liver microsomes, and the catalytic rates were not substantially different from wild type. Macaque CYP2B6 was polymorphic, and the genotype could partly account for variable enzyme activities of macaque CYP2B6. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Vitamin B-12 Concentrations in Breast Milk Are Low and Are Not Associated with Reported Household Hunger, Recent Animal-Source Food, or Vitamin B-12 Intake in Women in Rural Kenya.

    Science.gov (United States)

    Williams, Anne M; Chantry, Caroline J; Young, Sera L; Achando, Beryl S; Allen, Lindsay H; Arnold, Benjamin F; Colford, John M; Dentz, Holly N; Hampel, Daniela; Kiprotich, Marion C; Lin, Audrie; Null, Clair A; Nyambane, Geoffrey M; Shahab-Ferdows, Setti; Stewart, Christine P

    2016-05-01

    Breast milk vitamin B-12 concentration may be inadequate in regions in which animal-source food consumption is low or infrequent. Vitamin B-12 deficiency causes megaloblastic anemia and impairs growth and development in children. We measured vitamin B-12 in breast milk and examined its associations with household hunger, recent animal-source food consumption, and vitamin B-12 intake. In a cross-sectional substudy nested within a cluster-randomized trial assessing water, sanitation, hygiene, and nutrition interventions in Kenya, we sampled 286 women 1-6 mo postpartum. Mothers hand-expressed breast milk 1 min into a feeding after 90 min observed nonbreastfeeding. The Household Hunger Scale was used to measure hunger, food intake in the previous week was measured with the use of a food-frequency questionnaire (FFQ), and vitamin B-12 intake was estimated by using 24-h dietary recall. An animal-source food score was based on 10 items from the FFQ (range: 0-70). Breast milk vitamin B-12 concentration was measured with the use of a solid-phase competitive chemiluminescent enzyme immunoassay and was modeled with linear regression. Generalized estimating equations were used to account for correlated observations at the cluster level. Median (IQR) vitamin B-12 intake was 1.5 μg/d (0.3, 9.7 μg/d), and 60% of women consumed hunger prevalence was 27%; the animal-source food score ranged from 0 to 30 item-d/wk. Hunger and recent animal-source food and vitamin B-12 intake were not associated with breast milk vitamin B-12 concentrations. Maternal age was negatively associated with breast milk vitamin B-12 concentrations. Most lactating Kenyan women consumed less than the estimated average requirement of vitamin B-12 and had low breast milk vitamin B-12 concentrations. We recommend interventions that improve vitamin B-12 intake in lactating Kenyan women to foster maternal health and child development. The main trial was registered at clinicaltrials.gov as NCT01704105. © 2016

  1. Bond deformation paths and electronic instabilities of ultraincompressible transition metal diborides: Case study of OsB2 and IrB2

    Science.gov (United States)

    Zhang, R. F.; Legut, D.; Wen, X. D.; Veprek, S.; Rajan, K.; Lookman, T.; Mao, H. K.; Zhao, Y. S.

    2014-09-01

    The energetically most stable orthorhombic structure of OsB2 and IrB2 is dynamically stable for OsB2 but unstable for IrB2. Both diborides have substantially lower shear strength in their easy slip systems than their metal counterparts. This is attributed to an easy sliding facilitated by out-of-plane weakening of metallic Os-Os bonds in OsB2 and by an in-plane bond splitting instability in IrB2. A much higher shear resistance of Os-B and B-B bonds than Os-Os ones is found, suggesting that the strengthened Os-B and B-B bonds are responsible for hardness enhancement in OsB2. In contrast, an in-plane electronic instability in IrB2 limits its strength. The electronic structure of deformed diborides suggests that the electronic instabilities of 5d orbitals are their origin of different bond deformation paths. Neither IrB2 nor OsB2 can be intrinsically superhard.

  2. Observation of $B^+\\rightarrow J/\\psi 3\\pi^+ 2\\pi^-$ and $B^+\\rightarrow \\psi(2S) \\pi^+\\pi^+\\pi^-$ decays

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Archilli, Flavio; d'Argent, Philippe; Arnau Romeu, Joan; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Babuschkin, Igor; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baker, Sophie; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Baszczyk, Mateusz; Batozskaya, Varvara; Batsukh, Baasansuren; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Betancourt, Christopher; Betti, Federico; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bezshyiko, Iaroslava; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bitadze, Alexander; Bizzeti, Andrea; Blake, Thomas; Blanc, Frederic; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Boettcher, Thomas; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Bordyuzhin, Igor; Borgheresi, Alessio; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Bossu, Francesco; Boubdir, Meriem; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel Hugo; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; 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De Miranda, Jussara; De Paula, Leandro; De Serio, Marilisa; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Demmer, Moritz; Dendek, Adam; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Dijkstra, Hans; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dungs, Kevin; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Déléage, Nicolas; Easo, Sajan; Ebert, Marcus; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Farley, Nathanael; Farry, Stephen; Fay, Robert; Fazzini, Davide; Ferguson, Dianne; Fernandez Prieto, Antonio; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fini, Rosa Anna; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fleuret, Frederic; Fohl, Klaus; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Franco Lima, Vinicius; Frank, Markus; Frei, Christoph; Fu, Jinlin; Furfaro, Emiliano; Färber, Christian; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garcia Martin, Luis Miguel; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Garsed, Philip John; Gascon, David; Gaspar, Clara; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gizdov, Konstantin; Gligorov, V.V.; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gorelov, Igor Vladimirovich; Gotti, Claudio; Govorkova, Ekaterina; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Griffith, Peter; Grillo, Lucia; Gruberg Cazon, Barak Raimond; Grünberg, Oliver; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Göbel, Carla; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; Hatch, Mark; He, Jibo; Head, Timothy; Heister, Arno; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hombach, Christoph; Hopchev, P H; Hulsbergen, Wouter; Humair, Thibaud; Hushchyn, Mikhail; Hussain, Nazim; Hutchcroft, David; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jiang, Feng; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Kariuki, James Mwangi; Karodia, Sarah; Kecke, Matthieu; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khairullin, Egor; Khanji, Basem; Khurewathanakul, Chitsanu; Kirn, Thomas; Klaver, Suzanne; Klimaszewski, Konrad; Koliiev, Serhii; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Kosmyntseva, Alena; Kozachuk, Anastasiia; Kozeiha, Mohamad; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krokovny, Pavel; Kruse, Florian; Krzemien, Wojciech; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kuonen, Axel Kevin; Kurek, Krzysztof; Kvaratskheliya, Tengiz; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lanfranchi, Gaia; Langenbruch, Christoph; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Leflat, Alexander; Lefrançois, Jacques; Lefèvre, Regis; Lemaitre, Florian; Lemos Cid, Edgar; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Liu, Xuesong; Loh, David; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusiani, Alberto; Lyu, Xiao-Rui; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Maguire, Kevin; Malde, Sneha; Malinin, Alexander; Maltsev, Timofei; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massacrier, Laure Marie; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Melnychuk, Dmytro; Merk, Marcel; Merli, Andrea; Michielin, Emanuele; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Mogini, Andrea; Molina Rodriguez, Josue; Monroy, Ignacio Alberto; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Mulder, Mick; Mussini, Manuel; Müller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi Dung; Nguyen-Mau, Chung; Nieswand, Simon; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Oldeman, Rudolf; Onderwater, Gerco; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Pais, Preema Rennee; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parker, William; Parkes, Christopher; Passaleva, Giovanni; Pastore, Alessandra; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petrov, Aleksandr; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pikies, Malgorzata; Pinci, Davide; Pistone, Alessandro; Piucci, Alessio; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Pomery, Gabriela Johanna; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Poslavskii, Stanislav; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rama, Matteo; Ramos Pernas, Miguel; Rangel, Murilo; Raniuk, Iurii; Ratnikov, Fedor; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; dos Reis, Alberto; Remon Alepuz, Clara; Renaudin, Victor; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vicente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Rogozhnikov, Alexey; Roiser, Stefan; Rollings, Alexandra Paige; Romanovskiy, Vladimir; Romero Vidal, Antonio; Ronayne, John William; Rotondo, Marcello; Rudolph, Matthew Scott; Ruf, Thomas; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sadykhov, Elnur; Sagidova, Naylya; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schael, Stefan; Schellenberg, Margarete; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schubert, Konstantin; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sergi, Antonino; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Simone, Saverio; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Eluned; Smith, Iwan Thomas; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefko, Pavol; Stefkova, Slavorima; Steinkamp, Olaf; Stemmle, Simon; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Syropoulos, Vasileios; Szczekowski, Marek; Szumlak, Tomasz; T'Jampens, Stephane; Tayduganov, Andrey; Tekampe, Tobias; Tellarini, Giulia; Teubert, Frederic; Thomas, Eric; van Tilburg, Jeroen; Tilley, Matthew James; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Toriello, Francis; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Traill, Murdo; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tully, Alison; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valassi, Andrea; Valat, Sebastien; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vecchi, Stefania; van Veghel, Maarten; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Venkateswaran, Aravindhan; Vernet, Maxime; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Viemann, Harald; Vilasis-Cardona, Xavier; Vitti, Marcela; Volkov, Vladimir; Vollhardt, Achim; Voneki, Balazs; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Vázquez Sierra, Carlos; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wang, Jianchun; Ward, David; Wark, Heather Mckenzie; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wicht, Jean; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wraight, Kenneth; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yin, Hang; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zarebski, Kristian Alexander; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhang, Yu; Zhelezov, Alexey; Zheng, Yangheng; Zhokhov, Anatoly; Zhu, Xianglei; Zhukov, Valery; Zucchelli, Stefano

    2017-02-06

    The decays $B^+\\rightarrow J/\\psi 3\\pi^+ 2\\pi^-$ and $B^+\\rightarrow \\psi(2S) \\pi^+\\pi^+\\pi^-$ are observed for the first time using a data sample corresponding to an integrated luminosity of $3.0fb^{-1}$, collected by the LHCb experiment in proton-proton collisions at the centre-of-mass energies of 7 and 8 TeV. The branching fractions relative to that of $B^+ \\rightarrow \\psi(2S)K^+$ are measured to be \\begin{eqnarray*} \\frac {\\mathcal{B}\\left( B^+\\rightarrow J/\\psi 3\\pi^+ 2\\pi^- \\right)} {\\mathcal{B}\\left( B^+ \\rightarrow \\psi(2S)K^+ \\right)} & = & \\left( 1.88\\pm0.17\\pm0.09\\right)\\times10^{-2}, \\\\ \\frac {\\mathcal{B}\\left( B^+\\rightarrow \\psi(2S) \\pi^+\\pi^+\\pi^- \\right)} {\\mathcal{B}\\left( B^+ \\rightarrow \\psi(2S)K^+ \\right) } & = & \\left( 3.04\\pm0.50\\pm0.26\\right)\\times10^{-2}, \\end{eqnarray*} where the first uncertainties are statistical and the second are systematic.

  3. Influence of TiB2 particles on machinability and machining parameter optimization of TiB2/Al MMCs

    Directory of Open Access Journals (Sweden)

    Ruisong JIANG

    2018-01-01

    Full Text Available In situ formed TiB2 particle reinforced aluminum matrix composites (TiB2/Al MMCs have some extraordinary properties which make them be a promising material for high performance aero-engine blade. Due to the influence of TiB2 particles, the machinability is still a problem which restricts the application of TiB2/Al MMCs. In order to meet the industrial requirements, the influence of TiB2 particles on the machinability of TiB2/Al MMCs was investigated experimentally. Moreover, the optimal machining conditions for this kind of MMCs were investigated in this study. The major conclusions are: (1 the machining force of TiB2/Al MMCs is bigger than that of non-reinforced alloy and mainly controlled by feed rate; (2 the residual stress of TiB2/Al MMCs is compressive while that of non-reinforced alloy is nearly neutral; (3 the surface roughness of TiB2/Al MMCs is smaller than that of non-reinforced alloy under the same cutting speed, but reverse result was observed when the feed rate increased; (4 a multi-objective optimization model for surface roughness and material removal rate (MRR was established, and a set of optimal parameter combinations of the machining was obtained. The results show a great difference from SiC particle reinforced MMCs and provide a useful guide for a better control of machining process of this material.

  4. Transport properties and exponential n-values of Fe/MgB2 tapes with various MgB2 particle sizes

    International Nuclear Information System (INIS)

    Lezza, P.; Abaecherli, V.; Clayton, N.; Senatore, C.; Uglietti, D.; Suo, H.L.; Fluekiger, R.

    2004-01-01

    Fe/MgB 2 tapes have been prepared starting with pre-reacted binary MgB 2 powders. As shown by resistive and inductive measurements, the reduction of particle size to a few microns by ball milling has little influence on B c2 , while the superconducting properties of the individual MgB 2 grains are essentially unchanged. Reducing the particle size causes an enhancement of B irr from 14 to 16 T, while J c has considerably increased at high fields, its slope J c (B) being reduced. At 4.2 K, values of 5.3 x 10 4 and 1.2 x 10 3 A/cm 2 were measured at 3.5 and 10 T, respectively, suggesting a dominant role of the conditions at the grain interfaces. A systematic variation of these conditions at the interfaces is undertaken in order to determine the limit of transport properties for Fe/MgB 2 tapes. The addition of 5% Mg to MgB 2 powder was found to affect neither J c nor B c2 . For the tapes with the highest J c values, very high exponential n factors were measured: n=148, 89 and 17 at 3.5, 5 and 10 T, respectively and measurements of critical current versus applied strain have been performed. The mechanism leading to high transport critical current densities of filamentary Fe/MgB 2 tapes based on MgB 2 particles is discussed

  5. Measuring Trace Gas Emission from Multi-Distributed Sources Using Vertical Radial Plume Mapping (VRPM and Backward Lagrangian Stochastic (bLS Techniques

    Directory of Open Access Journals (Sweden)

    Thomas K. Flesch

    2011-09-01

    Full Text Available Two micrometeorological techniques for measuring trace gas emission rates from distributed area sources were evaluated using a variety of synthetic area sources. The vertical radial plume mapping (VRPM and the backward Lagrangian stochastic (bLS techniques with an open-path optical spectroscopic sensor were evaluated for relative accuracy for multiple emission-source and sensor configurations. The relative accuracy was calculated by dividing the measured emission rate by the actual emission rate; thus, a relative accuracy of 1.0 represents a perfect measure. For a single area emission source, the VRPM technique yielded a somewhat high relative accuracy of 1.38 ± 0.28. The bLS technique resulted in a relative accuracy close to unity, 0.98 ± 0.24. Relative accuracies for dual source emissions for the VRPM and bLS techniques were somewhat similar to single source emissions, 1.23 ± 0.17 and 0.94 ± 0.24, respectively. When the bLS technique was used with vertical point concentrations, the relative accuracy was unacceptably low,

  6. MASCARA-2 b

    DEFF Research Database (Denmark)

    Talens, G. J. J.; Justesen, A. B.; Albrecht, S.

    2018-01-01

    In this paper we present MASCARA-2 b, a hot Jupiter transiting the m(v) = 7.6 A2 star HD 185603. Since early 2015, MASCARA has taken more than 1.6 million flux measurements of the star, corresponding to a total of almost 3000 h of observations, revealing a periodic dimming in the flux with a depth...

  7. The SAMI2 Open Source Project

    Science.gov (United States)

    Huba, J. D.; Joyce, G.

    2001-05-01

    In the past decade, the Open Source Model for software development has gained popularity and has had numerous major achievements: emacs, Linux, the Gimp, and Python, to name a few. The basic idea is to provide the source code of the model or application, a tutorial on its use, and a feedback mechanism with the community so that the model can be tested, improved, and archived. Given the success of the Open Source Model, we believe it may prove valuable in the development of scientific research codes. With this in mind, we are `Open Sourcing' the low to mid-latitude ionospheric model that has recently been developed at the Naval Research Laboratory: SAMI2 (Sami2 is Another Model of the Ionosphere). The model is comprehensive and uses modern numerical techniques. The structure and design of SAMI2 make it relatively easy to understand and modify: the numerical algorithms are simple and direct, and the code is reasonably well-written. Furthermore, SAMI2 is designed to run on personal computers; prohibitive computational resources are not necessary, thereby making the model accessible and usable by virtually all researchers. For these reasons, SAMI2 is an excellent candidate to explore and test the open source modeling paradigm in space physics research. We will discuss various topics associated with this project. Research supported by the Office of Naval Research.

  8. Drivers of relationships affecting B2B firms in an e-commerce environment

    Directory of Open Access Journals (Sweden)

    Irene Samanta

    2014-09-01

    Full Text Available The advent of the internet has created numerous opportunities for B2B marketing professionals to enhance current marketing practices, including electronic relationships. However, the investigation of e-relationships and the factors that influence e-relationships in an internet environment is scant. Further, there appears to be no investigation of this phenomenon within the context of Greek B2B Medium-sized firms (MSF. Τhe research problem investigated in this research is: “Which drivers in B2B e-commerce use affect inter-firm relationships in medium-sized B2B firms?”. A framework for B2B e-commerce relationships in a changing and globalized environment was synthesised and integrated with the literature about relationship marketing to arrive at the following research issues: “How do relationship marketing drivers affect the management of B2B e-relationships?”. An explanatory quantitative research approach was used and quantitative data was collected from B2B firms in Greece, which represents a case of e-commerce progress during the last six years. Regarding social exchange, some important differences emerge where cooperation between B2B e-commerce firms is concerned. Suppliers engaged in electronic commerce are more committed and oriented to a long-term relationship than buyers, based on both previous and current experience with them. Confidence in the relationships, consistency and honesty with their obligations and the exchange of reliable, trustworthy information and advisory services between firms are important factors in the development and establishment of their e-relationships. The main contribution of this research is the development of a theoretical framework for e-relationships in medium-sized Β2Β firms. That framework is the first rigorously researched step towards understanding the importance of these powerful streams of relationship drivers in total, and the business activity of e-marketing and electronic relationships.

  9. Neutrons Flux Distributions of the Pu-Be Source and its Simulation by the MCNP-4B Code

    Science.gov (United States)

    Faghihi, F.; Mehdizadeh, S.; Hadad, K.

    Neutron Fluence rate of a low intense Pu-Be source is measured by Neutron Activation Analysis (NAA) of 197Au foils. Also, the neutron fluence rate distribution versus energy is calculated using the MCNP-4B code based on ENDF/B-V library. Theoretical simulation as well as our experimental performance are a new experience for Iranians to make reliability with the code for further researches. In our theoretical investigation, an isotropic Pu-Be source with cylindrical volume distribution is simulated and relative neutron fluence rate versus energy is calculated using MCNP-4B code. Variation of the fast and also thermal neutrons fluence rate, which are measured by NAA method and MCNP code, are compared.

  10. Enrichment of W2B5 from WO3 and B2O3 by Double SHS Method

    Directory of Open Access Journals (Sweden)

    Bora DERIN

    2018-02-01

    Full Text Available A second self-propagating high-temperature synthesis (SHS was carried out to enrich the W2B5 content in the SHS product containing a mixture of various tungsten boride compounds. In the experiment, the process called Double-SHS (D-SHS was conducted in two steps. In the first SHS reaction, an initial molar composition ratio of WO3:B2O3:Mg mixture was selected as 1:3:8. The product was then hot-leached with hydrochloric acid to eliminate MgO and Mg3B2O6 phases. The leached product, consisting of 72.6 wt.% W2B5, 16.1 wt.% WB, 8.4 wt.% W2B, and 2.9 wt.% W, was again reacted with the Mg and B2O3 mixture by second SHS. After another acid leaching step, W2B5 content in the D-SHS product was found to be 98.2 wt.%. The study showed that D-SHS is an effective method for boron enrichment in the tungsten compounds.DOI: http://dx.doi.org/10.5755/j01.ms.24.1.17834

  11. Synthesis of 9H-Indeno [1, 2-b] Pyrazine and 11H-Indeno [1, 2-b ...

    African Journals Online (AJOL)

    NICO

    Synthesis of 9H-Indeno [1, 2-b] Pyrazine and. 11H-Indeno [1, 2-b] Quinoxaline Derivatives in. One-step Reaction from 2-Bromo-4-chloro-1-indanone. S. Jasouri1,2, J. Khalafy1,*, M. Badali2 and R.H. Prager3. 1Department of Chemistry, Urmia University, Urmia 57154, Iran. 2Daana Pharmaceutical Co., P.O. Box 5181, Tabriz ...

  12. Peierls-distorted Ru-chains and boron dumbbells in Nb{sub 2}RuB{sub 2} and Ta{sub 2}RuB{sub 2} from first-principles calculations and experiments

    Energy Technology Data Exchange (ETDEWEB)

    Touzani, Rachid S.; Mbarki, Mohammed; Chen, Ximeng [Institute of Inorganic Chemistry, RWTH Aachen University (Germany); Fokwa, Boniface P.T. [Institute of Inorganic Chemistry, RWTH Aachen University (Germany); Department of Chemistry, University of California Riverside (UCR), Riverside, CA (United States)

    2016-09-15

    Nb{sub 2}RuB{sub 2} and Ta{sub 2}RuB{sub 2} phases were recently predicted by GGA-VASP structure optimization to crystallize in the Nb{sub 2}OsB{sub 2}-type structure. Although the Fe-based (Mo{sub 2}FeB{sub 2} type) and Os-based (Nb{sub 2}OsB{sub 2} type, superstructure variant of Mo{sub 2}FeB{sub 2} type) analogues have been synthesized and characterized successfully, the Ru-based phases remained unknown. Crystal structure prediction of Nb{sub 2}RuB{sub 2} and Ta{sub 2}RuB{sub 2} phases, using an evolutionary algorithm, led to the AlMn{sub 2}B{sub 2}-type structure in contrast to the aforementioned optimization; however, phonon calculations showed that the Nb{sub 2}OsB{sub 2}-type phases are dynamically more stable than the AlMn{sub 2}B{sub 2}-type phases. A slightly modified synthetic strategy finally led to the successful preparation of the predicted phases. The extremely quick arc-melting procedure, under argon atmosphere, not only led to a quantitative amount of the phases but also to single crystals suitable for structure determination. Powder and single-crystal X-ray diffraction as well as EDX analysis of the metal ratio have confirmed the GGA-VASP structure optimization: Nb{sub 2}RuB{sub 2} and Ta{sub 2}RuB{sub 2} compounds indeed crystallize isotypically with Nb{sub 2}OsB{sub 2} structure, a superstructure variant of Mo{sub 2}FeB{sub 2} type, in which B-dumbbells and Peierls-distorted Ru-chains are found. Susceptibility measurements on a Ta{sub 2}RuB{sub 2} single crystal reveal no superconducting transition down to 2 K, even though some features in the band structures of both phases, similar to those reported in superconducting NbRuB, hinted at possible superconductivity. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Surface decoration through electrostatic interaction leading to enhanced reactivity: Low temperature synthesis of nanostructured chromium borides (CrB and CrB2)

    International Nuclear Information System (INIS)

    Menaka,; Kumar, Bharat; Kumar, Sandeep; Ganguli, A.K.

    2013-01-01

    The present study describes a novel low temperature route at ambient pressure for the synthesis of nanocrystalline chromium borides (CrB and CrB 2 ) without using any flux or additives. The favorable and intimate mixing of nanoparticles of chromium acetate (Cr source) and boron forms an active chromium–boron precursor which decomposes at much lower temperature (400 °C) to form CrB (which is ∼1000 °C less than the known ambient pressure synthesis). The chromium acetate nanoparticles (∼5 nm) decorate the larger boron particles (150–200 nm) due to electrostatic interactions resulting from opposing surface charges of boron (zeta potential:+48.101 mV) and chromium acetate (zeta potential:−4.021 mV) in ethanolic medium and is evident in the TEM micrographs. The above method leads to the formation of pure CrB film like structure at 400 °C and nanospheres (40–60 nm) at 600 °C. Also, chromium diboride (CrB 2 ) nanoparticles (25 nm) could be obtained at 1000 °C. - Graphical abstract: Variation of surface charge of reactants, precursor and the products, chromium borides (CrB and CrB 2 ). Highlights: ► Novel borothermal reduction process for synthesis of chromium boride. ► Significant lowering of reaction temperature to obtain nanocrystalline chromium boride. ► Enhanced reactivity due to appropriate surface interactions

  14. Arsenic and other oxyanion-forming trace elements in an alluvial basin aquifer: Evaluating sources and mobilization by isotopic tracers (Sr, B, S, O, H, Ra)

    Energy Technology Data Exchange (ETDEWEB)

    Vinson, David S., E-mail: dsv3@duke.edu [Duke University, Division of Earth and Ocean Sciences, Box 90227, Durham, NC 27708 (United States); McIntosh, Jennifer C. [University of Arizona, Department of Hydrology and Water Resources, 1133 E. James E. Rogers Way, Tucson, AZ 85721 (United States); Dwyer, Gary S.; Vengosh, Avner [Duke University, Division of Earth and Ocean Sciences, Box 90227, Durham, NC 27708 (United States)

    2011-08-15

    Highlights: > Elevated natural As and F occur in the Willcox Basin aquifer of Arizona. > Oxyanion-forming elements are derived from volcanic-source aquifer sediments. > Sr isotopes trace sediment sources linked to oxyanion-forming trace elements. > {sup 87}Sr/{sup 86}Sr > 0.720 indicates Proterozoic crystalline-source sediment contributing low As. > Both sediment source and hydrogeochemical evolution (Ca/Na) affect As levels. - Abstract: The Willcox Basin is a hydrologically closed basin in semi-arid southeastern Arizona (USA) and, like many other alluvial basins in the southwestern USA, is characterized by oxic, near-neutral to slightly basic groundwater containing naturally elevated levels of oxyanion-forming trace elements such as As. This study evaluates the sources and mobilization of these oxyanionic trace elements of health significance by using several isotopic tracers of water-rock interaction and groundwater sources ({sup 87}Sr/{sup 86}Sr, {delta}{sup 34}S{sub SO4}, {delta}{sup 11}B, {delta}{sup 2}H, {delta}{sup 18}O, {sup 3}H). Values of {delta}{sup 2}H (-85 per mille to -64 per mille) and {delta}{sup 18}O (-11.8 per mille to -8.6 per mille) are consistent with precipitation and groundwater in adjacent alluvial basins, and low to non-detectable {sup 3}H activities further imply that modern recharge is slow in this semi-arid environment. Large variations in {sup 87}Sr/{sup 86}Sr ratios imply that groundwater has interacted with multiple sediment sources that constitute the basin-fill aquifer, including Tertiary felsic volcanic rocks, Paleozoic sedimentary rocks, and Proterozoic crystalline rocks. In general, low concentrations of oxyanion-forming trace elements and F{sup -} are associated with a group of waters exhibiting highly radiogenic values of {sup 87}Sr/{sup 86}Sr (0.72064-0.73336) consistent with waters in Proterozoic crystalline rocks in the mountain blocks (0.73247-0.75010). Generally higher As concentrations (2-29 {mu}g L{sup -1}), other

  15. Simulation of a silicon neutron detector coated with TiB2 absorber

    International Nuclear Information System (INIS)

    Krapohl, D; Nilsson, H-E; Petersson, S; Slavicek, T; Thungström, G; Pospisil, S

    2012-01-01

    Neutron radiation cannot be directly detected in semiconductor detectors and therefore needs converter layers. Planar clean-room processing can be used in the manufacturing process of semiconductor detectors with metal layers to produce a cost-effective device. We used the Geant4 Monte-Carlo toolkit to simulate the performance of a semiconductor neutron detector. A silicon photo-diode was coated with vapour deposited titanium, aluminium thin films and a titaniumdiboride (TiB 2 ) neutron absorber layer. The neutron capture reaction 10B(n, alpha)7Li is taken advantage of to create charged particles that can be counted. Boron-10 has a natural abundance of about SI 19.8%. The emitted alpha particles are absorbed in the underlying silicon detector. We varied the thickness of the converter layer and ran the simulation with a thermal neutron source in order to find the best efficiency of the TiB 2 converter layer and optimize the clean room process.

  16. New ternary tantalum borides containing boron dumbbells: Experimental and theoretical studies of Ta2OsB2 and TaRuB

    International Nuclear Information System (INIS)

    Mbarki, Mohammed; Touzani, Rachid St.; Rehorn, Christian W.G.; Gladisch, Fabian C.; Fokwa, Boniface P.T.

    2016-01-01

    The new ternary transition metal-rich borides Ta 2 OsB 2 and TaRuB have been successfully synthesized by arc-melting the elements in a water-cooled crucible under an argon atmosphere. The crystal structures of both compounds were solved by single-crystal X-ray diffraction and their metal compositions were confirmed by EDX analysis. It was found that Ta 2 OsB 2 and TaRuB crystallize in the tetragonal Nb 2 OsB 2 (space group P4/mnc, no. 128) and the orthorhombic NbRuB (space group Pmma, no. 51) structure types with lattice parameters a=5.878(2) Å, c=6.857(2) Å and a=10.806(2) Å, b=3.196(1) Å, c=6.312(2) Å, respectively. Furthermore, crystallographic, electronic and bonding characteristics have been studied by density functional theory (DFT). Electronic structure relaxation has confirmed the crystallographic parameters while COHP bonding analysis indicates that B 2 -dummbells are the strongest bonds in both compounds. Moreover, the formation of osmium dumbbells in Ta 2 OsB 2 through a Peierls distortion along the c-axis, is found to be the origin of superstructure formation. Magnetic susceptibility measurements reveal that the two phases are Pauli paramagnets, thus confirming the theoretical DOS prediction of metallic character. Also hints of superconductivity are found in the two phases, however lack of single phase samples has prevented confirmation. Furthermore, the thermodynamic stability of the two modifications of AMB (A=Nb, Ta; M =Ru, Os) are studied using DFT, as new possible phases containing either B 4 - or B 2 -units are predicted, the former being the most thermodynamically stable modification. - Graphical abstract: The two new ternary tantalum borides, Ta 2 OsB 2 and TaRuB, have been discovered. Their crystal structures contain boron dumbbells, which are the strongest bonds. Peirls distortion is found responsible for Os 2 -dumbbells formation in Ta 2 OsB 2 . Ta 2 OsB 2 and TaRuB are Pauli paramagnet and potential superconductors. - Highlights:

  17. Emergence of canine parvovirus subtype 2b (CPV-2b) infections in Australian dogs.

    Science.gov (United States)

    Clark, Nicholas J; Seddon, Jennifer M; Kyaw-Tanner, Myat; Al-Alawneh, John; Harper, Gavin; McDonagh, Phillip; Meers, Joanne

    2018-03-01

    Tracing the temporal dynamics of pathogens is crucial for developing strategies to detect and limit disease emergence. Canine parvovirus (CPV-2) is an enteric virus causing morbidity and mortality in dogs around the globe. Previous work in Australia reported that the majority of cases were associated with the CPV-2a subtype, an unexpected finding since CPV-2a was rapidly replaced by another subtype (CPV-2b) in many countries. Using a nine-year dataset of CPV-2 infections from 396 dogs sampled across Australia, we assessed the population dynamics and molecular epidemiology of circulating CPV-2 subtypes. Bayesian phylogenetic Skygrid models and logistic regressions were used to trace the temporal dynamics of CPV-2 infections in dogs sampled from 2007 to 2016. Phylogenetic models indicated that CPV-2a likely emerged in Australia between 1973 and 1988, while CPV-2b likely emerged between 1985 and 1998. Sequences from both subtypes were found in dogs across continental Australia and Tasmania, with no apparent effect of climate variability on subtype occurrence. Both variant subtypes exhibited a classical disease emergence pattern of relatively high rates of evolution during early emergence followed by subsequent decreases in evolutionary rates over time. However, the CPV-2b subtype maintained higher mutation rates than CPV-2a and continued to expand, resulting in an increase in the probability that dogs will carry this subtype over time. Ongoing monitoring programs that provide molecular epidemiology surveillance will be necessary to detect emergence of new variants and make informed recommendations to develop reliable detection and vaccine methods. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. On Hubbell's rectangular source integral

    International Nuclear Information System (INIS)

    Stalker, John

    2001-01-01

    The integral H(a,b)=∫ 0 b ∫ 0 a dx dy/(1+x 2 +y 2 ) arises naturally in the study of radiation from a rectangular source and has been studied by many authors. This paper introduces a new series expansion which is rapidly convergent for large a and b

  19. b af B2B serviceydelser

    DEFF Research Database (Denmark)

    Grünbaum, Niels Nolsøe; Hollensen, Svend; Andresen, Marc

    2011-01-01

    I den tidlige B-t-B-købsadfærdslitteratur har man lagt megen vægt på, at købsadfærden i forbindelse med B-t-B-serviceydelser er meget rationel præget. Gennem en større eksplorativ undersøgelse af danske virksomheders indkøb af konsulentydelser inden for hr, har forfatterne fået indblik i de fakto...

  20. MgB_{2} nonlinear properties investigated under localized high rf magnetic field excitation

    Directory of Open Access Journals (Sweden)

    Tamin Tai

    2012-12-01

    Full Text Available The high transition temperature and low surface resistance of MgB_{2} attracts interest in its potential application in superconducting radio frequency accelerating cavities. However, compared to traditional Nb cavities, the viability of MgB_{2} at high rf fields is still open to question. Our approach is to study the nonlinear electrodynamics of the material under localized rf magnetic fields. Because of the presence of the small superconducting gap in the π band, the nonlinear response of MgB_{2} at low temperature is potentially complicated compared to a single-gap s-wave superconductor such as Nb. Understanding the mechanisms of nonlinearity coming from the two-band structure of MgB_{2}, as well as extrinsic sources of nonlinearity, is an urgent requirement. A localized and strong rf magnetic field, created by a magnetic write head, is integrated into our nonlinear-Meissner-effect scanning microwave microscope [T. Tai et al., IEEE Trans. Appl. Supercond. 21, 2615 (2011ITASE91051-822310.1109/TASC.2010.2096531]. MgB_{2} films with thickness 50 nm, fabricated by a hybrid physical-chemical vapor deposition technique on dielectric substrates, are measured at a fixed location and show a strongly temperature-dependent third harmonic response. We propose that several possible mechanisms are responsible for this nonlinear response.

  1. Electronic and elastic properties of new semiconducting oP{sub 12}-type RuB{sub 2} and OsB{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Hao Xianfeng; Xu Yuanhui; Gao Faming, E-mail: xfhao1980@yahoo.com.cn [Key Laboratory of Applied Chemistry, Yanshan University, Qinhuangdao 066004 (China)

    2011-03-30

    Using first-principles total energy calculations we investigate the structural, elastic and electronic properties of new hypothetical oP{sub 12}-type phase RuB{sub 2} and OsB{sub 2}. The calculations indicate that the oP{sub 12}-type phase RuB{sub 2} and OsB{sub 2} are thermodynamically and mechanically stable. Remarkably, the new phases RuB{sub 2} and OsB{sub 2} are predicted to be semiconductors, and the appearance of band gaps is ascribed to the enhanced B-B covalent hybridization. Compared to metallic oP{sub 6}-type RuB{sub 2} and OsB{sub 2} phases, the new phases possess similar mechanical properties and hardness. The combination of the probability of tunable electronic properties, strong stiffness and high hardness make RuB{sub 2} and OsB{sub 2} attractive and interesting for advanced applications.

  2. A formal guidance for handling different uncertainty sources employed in the level 2 PSA

    International Nuclear Information System (INIS)

    Ahn, Kwang Il; Yang, Joon Eon; Ha, Jae Joo

    2004-01-01

    The methodological framework of the level 2 PSA appears to be currently standardized in a formalized fashion, but there have been different opinions on the way the sources of uncertainty are characterized and treated. This is primarily because the level 2 PSA deals with complex phenomenological processes that are deterministic in nature rather than random processes, and there are no probabilistic models characterizing them clearly. As a result, the probabilistic quantification of the level 2 PSA CET/APET is often subjected to two sources of uncertainty: (a) incomplete modeling of accident pathways or different predictions for the behavior of phenomenological events and (b) expert-to-expert variation in estimating the occurrence probability of phenomenological events. While a clear definition of the two sources of uncertainty involved in the level 2 PSA makes it possible to treat an uncertainty in a consistent manner, careless application of these different sources of uncertainty may produce different conclusions in the decision-making process. The primary purpose of this paper is to characterize typical sources of uncertainty that would often be addressed in the level 2 PSA and to provide a formal guidance for quantifying their impacts on the PSA level 2 risk results. An additional purpose of this paper is to give a formal approach on how to combine random uncertainties addressed in the level 1 PSA with subjectivistic uncertainties addressed in the level 2 PSA

  3. Phase and Microstructural Correlation of Spark Plasma Sintered HfB2-ZrB2 Based Ultra-High Temperature Ceramic Composites

    Directory of Open Access Journals (Sweden)

    Ambreen Nisar

    2017-07-01

    Full Text Available The refractory diborides (HfB2 and ZrB2 are considered as promising ultra-high temperature ceramic (UHTCs where low damage tolerance limits their application for the thermal protection system in re-entry vehicles. In this regard, SiC and CNT have been synergistically added as the sintering aids and toughening agents in the spark plasma sintered (SPS HfB2-ZrB2 system. Herein, a novel equimolar composition of HfB2 and ZrB2 has shown to form a solid-solution which then allows compositional tailoring of mechanical properties (such as hardness, elastic modulus, and fracture toughness. The hardness of the processed composite is higher than the individual phase hardness up to 1.5 times, insinuating the synergy of SiC and CNT reinforcement in HfB2-ZrB2 composites. The enhanced fracture toughness of CNT reinforced composite (up to a 196% increment surpassing that of the parent materials (ZrB2/HfB2-SiC is attributed to the synergy of solid solution formation and enhanced densification (~99.5%. In addition, the reduction in the analytically quantified interfacial residual tensile stress with SiC and CNT reinforcements contribute to the enhancement in the fracture toughness of HfB2-ZrB2-SiC-CNT composites, mandatory for aerospace applications.

  4. The purification step is not crucial in EIA measurements of thromboxane B2 and 11-dehydrothromboxane B2 in human plasma.

    Science.gov (United States)

    Sadilkova, Lenka; Paluch, Zoltan; Mottlova, Jirina; Bednar, Frantisek; Alusik, Stefan

    2012-01-01

    Thromboxane B2 (TxB2) and particularly 11-dehydrothromboxane B2 (11-dTxB2) are widely used as prognostic risk markers of platelet activation in cardiovascular diseases. The main errors in TxB2 and 11-dTxB2 determination include either low concentrations of circulating TxB2 (1 - 2 pg/mL) and 11-dTxB2 (0.9 - 4.3 pg/mL) or rather high transiency (mean TxB2 half-life is approximately 5 minutes) as well as an incorrect pre-analytical phase set up. The aim of this study was to investigate the impact of a widely used purification step on the results of enzyme immunosorbent assay (EIA)--based measurement of the two selected thromboxanes. For the purpose of this study, 20 plasma samples (10 healthy donors, 10 patients under treatment with acetylsalicylic acid) were screened for TxB2 and 11-dTxB2 concentrations using commercial competitive EIA kits (Cayman Chemicals, Tallinn, Estonia; Neogen, Lexington, KY, USA) with or without the introduction of the purification procedure. The purification step does not significantly affect the results of EIA measurements of the two of TxA2 metabolites (TxB2, 11-dTxB2) in human plasma. The levels of TxB2 and 11-dTxB2 determined in the plasma samples were not significantly changed (p < 0.05) when the purification step was omitted compared to the purified samples. This study establishes a protocol allowing for reliable and reproducible plasma TxB2 and 11-dTxB2 EIA measurement for routine basic screening of platelet function.

  5. Multiple antibacterial histone H2B proteins are expressed in tissues of American oyster.

    Science.gov (United States)

    Seo, Jung-Kil; Stephenson, Jeana; Noga, Edward J

    2011-03-01

    We have previously identified a histone H2B isomer (cvH2B-1) from tissue extracts of the bivalve mollusk, the American oyster (Crassostrea virginica). In this paper, we isolate an additional three antibacterial proteins from acidified gill extract by preparative acid-urea-polyacrylamide gel electrophoresis and reversed-phase high performance liquid chromatography. Extraction of these proteins from tissue was best accomplished by briefly boiling the tissues in a weak acetic acid solution. Addition of protease inhibitors while boiling resulted in somewhat lower yields, with one protein being totally absent with this method. Via mass spectrometry, the masses of one of these purified proteins was 13607.0Da (peak 2), which is consistent with the molecular weight of histone H2B. In addition, via western-blotting using anti-calf histone H2B antibody, all three proteins were positive and were thus named cvH2B-2, cvH2B-3 and cvH2B-4. The antibacterial activity of cvH2B-2 was similar to that of cvH2B-1, with activity against a Gram-positive bacterium (Lactococcus lactis subsp. lactis; minimum effective concentration [MEC] 52-57μg/mL) but inactive against Staphylococcus aureus (MEC>250μg/mL). However, both proteins had relatively potent activity against the Gram-negative oyster pathogen Vibrio parahemolyticus (MEC 11.5-14μg/mL) as well as the human pathogen Vibrio vulnificus (MEC 21.3-25.3μg/mL). cvH2B-3 and cvH2B-4 also had similarly strong activity against Vibrio vulnificus. These data provide further evidence for the antimicrobial function of histone H2B isomers in modulating bacterial populations in oyster tissues. The combined estimated concentrations of these histone H2B isomers were far above the inhibitory concentrations for the tested vibrios, including human pathogens. Our results indicate that the highly conserved histone proteins might be important components not only of immune defenses in oysters but have the potential to influence the abundance of a

  6. The ISS 2B PVTCS Ammonia Leak: An Operational History

    Science.gov (United States)

    Vareha, Anthony

    2014-01-01

    In 2006, the Photovoltaic Thermal Control System (PVTCS) for the International Space Station's 2B power channel began leaking ammonia at a rate of approximately 1.5lbm/year (out of a starting approximately 53lbm system ammonia mass). Initially, the operations strategy was "feed the leak," a strategy successfully put into action via Extra Vehicular Activity during the STS-134 mission. During this mission the system was topped off with ammonia piped over from a separate thermal control system. This recharge was to have allowed for continued power channel operation into 2014 or 2015, at which point another EVA would have been required. Without these periodic EVAs to refill the 2B coolant system, the channel would eventually leak enough fluid as to risk pump cavitation and system failure, resulting in the loss of the 2B power channel - the most critical of the Space Station's 8 power channels. In mid-2012, the leak rate increased to approximately 5lbm/year. Once discovered, an EVA was planned and executed within a 5 week timeframe to drastically alter the architecture of the PVTCS via connection to a dormant thermal control system not intended to be utilized as anything other than spare components. The purpose of this rerouting of the TCS was to increase system volume and to isolate the photovoltaic radiator, thought to be the likely leak source. This EVA was successfully executed on November 1st, 2012 and left the 2B PVTCS in a configuration where the system was now being adequately cooled via a totally different radiator than what the system was designed to utilize. Unfortunately, data monitoring over the next several months showed that the isolated radiator was not leaking, and the system itself continued to leak steadily until May 9th, 2013. It was on this day that the ISS crew noticed the visible presence of ammonia crystals escaping from the 2B channel's truss segment, signifying a rapid acceleration of the leak from 5lbm/year to 5lbm/day. Within 48 hours of the

  7. Scale-up operations of CuSOB4B-NaB2BSOB4B electrolytic ...

    African Journals Online (AJOL)

    Scale-up techniques were established for an Inclined Cathode Electrochemical Cell (ICEC) for the removal of copper ions from a CuSOB4B-NaB2BSOB4B solution at reduced operation power consumption. The scale-up relationshi-ps were derived and applied in conjunction with scale-up factors. With a scale-up factor of 2, ...

  8. Quantitative and quality test of cross section library ENDF/B-b2

    International Nuclear Information System (INIS)

    Zajac, R.; Necas, V.

    2006-01-01

    This article includes a test or in other words data verification of neutron ENDF/B-VIIb2 sub library. The first part consists from the process of preparation ACE files by NJOY 99.90. The starting point of data verification describes needed patches in NJOY 99.90, which are necessary to do for correctly production of ACE files. After the obtaining ACE files follow the test of all ACE files through GODIVA - input file for MCNP. GODIVA is high enrichment sphere of U-235, where every material is added as impurity. The aim of GODIVA test is to obtain a certainty if produced ACE files are able to run through MCNP. The second part of this article begins with choose of benchmarks from 'International Handbook of Evaluated Criticality Safety Benchmark Experiments, 2005'. From this source of criticality experiments were separated some benchmarks for quality verification of ACE files by MCNP (Authors)

  9. K2-60b and K2-107b. A Sub-Jovian and a Jovian Planet from the K2 Mission

    International Nuclear Information System (INIS)

    Eigmüller, Philipp; Csizmadia, Szilard; Smith, Alexis M. S.; Cabrera, Juan; Erikson, Anders; Gandolfi, Davide; Barragán, Oscar; Persson, Carina M.; Fridlund, Malcolm; Donati, Paolo; Cusano, Felice; Korth, Judith; Grziwa, Sascha; Prieto-Arranz, Jorge; Nespral, David; Deeg, Hans J.; Saario, Joonas; Cochran, William D.; Endl, Michael; Guenther, Eike W.

    2017-01-01

    We report the characterization and independent detection of K2-60b, as well as the detection and characterization of K2-107b, two transiting hot gaseous planets from the K2 space mission. We confirm the planetary nature of the two systems and determine their fundamental parameters combining the K2 time-series data with FIES@NOT and HARPS-N@TNG spectroscopic observations. K2-60b has a radius of 0.683 ± 0.037 R Jup and a mass of 0.426 ± 0.037 M Jup and orbits a G4 V star with an orbital period of 3.00267 ± 0.00006 days. K2-107b has a radius of 1.44 ± 0.15 R Jup and a mass of 0.84 ± 0.08 M Jup and orbits an F9 IV star every 3.31392 ± 0.00002 days. K2-60b is among the few planets at the edge of the so-called “desert” of short-period sub-Jovian planets. K2-107b is a highly inflated Jovian planet orbiting an evolved star about to leave the main sequence.

  10. K2-60b and K2-107b. A Sub-Jovian and a Jovian Planet from the K2 Mission

    Energy Technology Data Exchange (ETDEWEB)

    Eigmüller, Philipp; Csizmadia, Szilard; Smith, Alexis M. S.; Cabrera, Juan; Erikson, Anders [Institute of Planetary Research, German Aerospace Center, Rutherfordstrasse 2, D-12489 Berlin (Germany); Gandolfi, Davide; Barragán, Oscar [Dipartimento di Fisica, Universitá di Torino, via P. Giuria 1, I-10125 Torino (Italy); Persson, Carina M.; Fridlund, Malcolm [Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, SE-439 92 Onsala (Sweden); Donati, Paolo; Cusano, Felice [INAF—Osservatorio Astronomico di Bologna, Via Ranzani, 1, I-40127, Bologna (Italy); Korth, Judith; Grziwa, Sascha [Rheinisches Institut für Umweltforschung an der Universität zu Köln, Aachener Strasse 209, D-50931 Köln (Germany); Prieto-Arranz, Jorge; Nespral, David; Deeg, Hans J. [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Saario, Joonas [Nordic Optical Telescope, Apartado 474, E-38700, Santa Cruz de La Palma (Spain); Cochran, William D.; Endl, Michael [Department of Astronomy and McDonald Observatory, University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712 (United States); Guenther, Eike W. [Thüringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenberg (Germany); and others

    2017-03-01

    We report the characterization and independent detection of K2-60b, as well as the detection and characterization of K2-107b, two transiting hot gaseous planets from the K2 space mission. We confirm the planetary nature of the two systems and determine their fundamental parameters combining the K2 time-series data with FIES@NOT and HARPS-N@TNG spectroscopic observations. K2-60b has a radius of 0.683 ± 0.037 R {sub Jup} and a mass of 0.426 ± 0.037 M {sub Jup} and orbits a G4 V star with an orbital period of 3.00267 ± 0.00006 days. K2-107b has a radius of 1.44 ± 0.15 R {sub Jup} and a mass of 0.84 ± 0.08 M {sub Jup} and orbits an F9 IV star every 3.31392 ± 0.00002 days. K2-60b is among the few planets at the edge of the so-called “desert” of short-period sub-Jovian planets. K2-107b is a highly inflated Jovian planet orbiting an evolved star about to leave the main sequence.

  11. Marketing communications in industrial B2b markets enhancing the value of the corporate brand relying on common added values

    Directory of Open Access Journals (Sweden)

    Jose Ignacio Monrabal

    2013-09-01

    Full Text Available Today, industrial Business-to-Business (B2B markets are mainly characterized by a highly trained customer for making rational decisions in a highly competitive and global market, requiring more than ever organizations to approach their markets with a single and consistent message. Such demanding scenario requires to define a corporate brand transmitting in one message all the advantages that a Customer may appreciate in the long-term, based not only on what the company stands for in the market, but also the benefits of all its products throughout its portfolio. Such elements are referred as Common Added Values (CAVs, being some general examples the technology, quality, innovation and reliability; the capacity, infrastructure and distribution network; after-sales service policies, support and training; or the price and financial policies. This paper tries to explain the source of this need, describing the main differences between a brand communications model focused on the product or including the main B2B corporate values; and highlighting the main CAVs, to get an industry player either small or large, can succeed in generating brand equity through an integrated marketing communications strategy.

  12. LytB1 and LytB2 of Mycobacterium tuberculosis Are Not Genetically Redundant.

    Directory of Open Access Journals (Sweden)

    Amanda Claire Brown

    Full Text Available Mycobacterium tuberculosis synthesises isoprenoid precursors via the MEP/DOXP pathway and at least five enzymes in the pathway (Dxs1, Dxr/IspC, IspD, IspF, and GcpE/IspG are required for growth in vitro. We investigated the role of LytB (IspH in M. tuberculosis; M. tuberculosis is unusual in that it has two homologs-LytB1 and LytB2. We were unable to delete the lytB2 gene unless we provided an additional copy elsewhere, demonstrating that this is the essential homolog. We expressed lytB1 from the lytB2 promoter and confirmed that this could not complement for loss of function of lytB2, despite LytB1 possessing all the previously described conserved critical residues. Interestingly the sole LytB homolog of Mycobacterium smegmatis was able to compensate for loss of LytB2 in M. tuberculosis. We tested translational fusions of LytB1 and LytB2 for functionality in M. tuberculosis, but only a fusion with 90% N-terminal LytB2 and 10% C-terminal LytB1 was functional. In order to identify the key difference between the two proteins, site directed mutagenesis was used to change LytB2 residues into their counterparts in LytB1. None of these amino acid substitutions was essential for function and all lytB2 mutant alleles were functional. In contrast, mutation of the key residues for [Fe4S4] cluster formation, as well as a catalytic residue in LytB1 did not result in functional complementation. Thus, although LytB1 and LytB2 are not genetically redundant, this is not dependent on small amino acid changes, but is likely to be a result of major overall structural differences.

  13. Social media as a support tool for B2B communication

    OpenAIRE

    Thapa Magar, Chandani

    2016-01-01

    This research was commissioned by Oulu University of Applied Sciences and a Finnish tech company Uros Ltd. As social media adoption is growing steadily in the contemporary consumer marketing, not many cases can be found where Social Media has been successfully adopted and used in a B2B scenario. Thus, it has remained as a reserved matter for many B2B companies, which still follow the tried-and-true business principles polished through traditional marketing. This research paper aims to enhanc...

  14. Customer satisfaction in B2B cloud services

    OpenAIRE

    Turunen, Helinä

    2013-01-01

    Tutkimuksen tavoitteena on kirjallisuuskatsauksen kautta esitellä B2B-pilvipalveluiden asiakastyytyväisyyteen vaikuttavia seikkoja, ja kuinka näitä seikkoja tulisi ottaa huomioon asiakastyytyväisyyden parantamisessa. Tässä tutkimuksessa verkkopohjaiseen liiketoimintaan liittyvää asiakastyytyväisyyden tutkimusta käytettiin pohjana etsiessä asiakastyytyväisyyteen vaikuttavia seikkoja pilvipalveluissa. Tutkimuksessa vertaillaan asiakastyytyväisyyteen vaikuttavia seikkoja vertailemalla tyytyväisy...

  15. B K Godwal

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. B K Godwal. Articles written in Bulletin of Materials Science. Volume 23 Issue 2 April 2000 pp 151-154 Instrumentation. A CCD area detector for X-ray diffraction under high pressure for rotating anode source · Amar Sinha Alka B Garg V Vijayakumar B K Godwal S K Sikka.

  16. Carbon-coated boron using low-cost naphthalene for substantial enhancement of Jc in MgB2 superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Ranot, Mahipal; Shinde, K. P.; Oh, Y. S.; Kang, S. H.; Jang, S. H.; Hwang, D. Y.; Chung, K. C. [Korea Institute of Materials Science, Changwon (Korea, Republic of)

    2017-09-15

    Carbon coating approach is used to prepare carbon-doped MgB{sub 2} bulk samples using low-cost naphthalene (C{sub 10}H{sub 8}) as a carbon source. The coating of carbon (C) on boron (B) powders was achieved by direct pyrolysis of naphthalene at 120 degrees C and then the C-coated B powders were mixed well with appropriate amount of Mg by solid state reaction method. X-ray diffraction analysis revealed that there is a noticeable shift in (100) and (110) Bragg reflections towards higher angles, while no shift was observed in (002) reflections for MgB2 doped with carbon. As compared to un-doped MgB{sub 2}, a systematic enhancement in Jc(H) properties with increasing carbon doping level was observed for naphthalene-derived C-doped MgB{sub 2} samples. The substantial enhancement in Jc is most likely due to the incorporation of C into MgB{sub 2} lattice and the reduction in crystallite size, as evidenced by the increase in the FWHM values for doped samples.

  17. Advanced complex analysis a comprehensive course in analysis, part 2b

    CERN Document Server

    Simon, Barry

    2015-01-01

    A Comprehensive Course in Analysis by Poincaré Prize winner Barry Simon is a five-volume set that can serve as a graduate-level analysis textbook with a lot of additional bonus information, including hundreds of problems and numerous notes that extend the text and provide important historical background. Depth and breadth of exposition make this set a valuable reference source for almost all areas of classical analysis. Part 2B provides a comprehensive look at a number of subjects of complex analysis not included in Part 2A. Presented in this volume are the theory of conformal metrics (includ

  18. The formation of AlB2 in an Al-B master alloy

    International Nuclear Information System (INIS)

    Wang Xiaoming

    2005-01-01

    The formation of borides in an Al-3 wt.%B master alloy, produced via chemical reactions of KBF 4 and aluminium has been investigated. The chemical reactions produce boron, which dissolves into molten aluminium and subsequently forms aluminium borides. Backscattered electron imaging (BEI) of the Al-3 wt.%B master alloy under a scanning electron microscope (SEM) revealed the presence of two types of phases that contain different levels of boron. Combined with X-ray diffraction (XRD) results, the two types of phases are identified as AlB 2 on AlB 12 . This gives a direct evidence for a peritectic reaction of AlB 12 and aluminium, which produces AlB 2 . The thermodynamic properties of the reactions that may be involved are examined, and the presence of AlB 12 phase in the master alloy explained. The observed microstructure is explained according to the peritectic reaction in an Al-B phase diagram. The stability of AlB 2 and AlB 12 at lower temperature than 975 deg. C is clarified

  19. Strategic B2B customer experience management: the importance of outcomes-based measures

    OpenAIRE

    Zolkiewski, Judy; Story, Victoria; Burton, Jamie; Chan, Paul; Gomes, Andre; Hunter-Jones, Philippa; O’Malley, Lisa; Peters, Linda D.; Raddats, Chris; Robinson, William

    2017-01-01

    Purpose\\ud \\ud The purpose of this paper is to critique the adequacy of efforts to capture the complexities of customer experience in a business-to-business (B2B) context using input–output measures. The paper introduces a strategic customer experience management framework to capture the complexity of B2B service interactions and discusses the value of outcomes-based measurement.\\ud Design/methodology/approach\\ud \\ud This is a theoretical paper that reviews extant literature related to B2B cu...

  20. Social Media within a B2B context : A qualitative study about how industrial corporations can use social media to maintain B2B relationships

    OpenAIRE

    Andersén, Sophia; Bengtsson, Annie; Gilén, Sandra

    2014-01-01

    The last thirty years there has been a dramatic change in relationship marketing. The use of computers connected to the Internet at work places has increased over time and social media is widely used in marketing strategies. Social media is a new phenomenon to communicate with each other, it enables market information based on individual consumer’s experiences. Therefore managers are seeking a way to incorporate social media into their strategies, but this is more common within B2C than B2B. ...

  1. Magneto-optical and electromagnetic studies of core connectivity and weak-link behaviour in Cu/MgB2 and Ni/MgB2 wires and tapes

    International Nuclear Information System (INIS)

    Polyanskii, A; Beilin, V; Felner, I; Tsindlekht, M I; Yashchin, E; Dul'kin, E; Galstyan, E; Roth, M; Senkowicz, B; Hellstrom, E

    2004-01-01

    Critical current density, ac susceptibility (real part χ' and magneto-optical (MO) imaging were used to characterize round wire and tapes made from pre-reacted MgB 2 powder by the powder-in-tube method. Magnetic susceptibility measurements indicated the existence of large-scale weak-link networks in the cores of as-deformed Ni/MgB 2 and Cu/MgB 2 wires and tapes. As-deformed samples showed a two-step transition in χ' versus T traces as evidence of weak links in the tape core. The first heat treatment (HT) of as-deformed tapes led to a sharp susceptibility transition, very strong connection in the tape core as seen in MO images, and high critical current. A second rolling of an as-sintered tape induced a network of defects in the brittle core and gave rise to χ' curve broadening, but did not result in a two-step transition. These data show that deformation-induced cracks are not the primary source of weak-link behaviour. A large decrease in transport current was also registered in this sample. The second HT, for 30 min, restored the sharp magnetic transition and high transport current. Alternating areas of strong and weak connection in the tape core have been observed on MO images. Fast heating and cooling of the as-deformed tape with no dwell time at the maximum temperature resulted in a strongly linked core with a sharp transition and increased transport current. After fast HT, no mechanical defects were observed in MO images. Such fast transformation could be explained by rapid sintering due to highly strained MgB 2 grains

  2. Clinical relevance of ErbB-2/HER2 nuclear expression in breast cancer

    International Nuclear Information System (INIS)

    Schillaci, Roxana; Charreau, Eduardo H; Maronna, Esteban; Roa, Juan C; Elizalde, Patricia V; Guzmán, Pablo; Cayrol, Florencia; Beguelin, Wendy; Díaz Flaqué, María C; Proietti, Cecilia J; Pineda, Viviana; Palazzi, Jorge; Frahm, Isabel

    2012-01-01

    The biological relevance of nuclear ErbB-2/HER2 (NuclErbB-2) presence in breast tumors remains unexplored. In this study we assessed the clinical significance of ErbB-2 nuclear localization in primary invasive breast cancer. The reporting recommendations for tumor marker prognostic studies (REMARK) guidelines were used as reference. Tissue microarrays from a cohort of 273 primary invasive breast carcinomas from women living in Chile, a Latin American country, were examined for membrane (MembErbB-2) and NuclErbB-2 expression by an immunofluorescence (IF) protocol we developed. ErbB-2 expression was also evaluated by immunohistochemistry (IHC) with a series of antibodies. Correlation between NuclErbB-2 and MembErbB-2, and between NuclErbB-2 and clinicopathological characteristics of tumors was studied. The prognostic value of NuclErbB-2 in overall survival (OS) was evaluated using Kaplan-Meier method, and Cox model was used to explore NuclErbB-2 as independent prognostic factor for OS. The IF protocol we developed showed significantly higher sensitivity for detection of NuclErbB-2 than IHC procedures, while its specificity and sensitivity to detect MembErbB-2 were comparable to those of IHC procedures. We found 33.6% NuclErbB-2 positivity, 14.2% MembErbB-2 overexpression by IF, and 13.0% MembErbB-2 prevalence by IHC in our cohort. We identified NuclErbB-2 positivity as a significant independent predictor of worse OS in patients with MembErbB-2 overexpression. NuclErbB-2 was also a biomarker of lower OS in tumors that overexpress MembErbB-2 and lack steroid hormone receptors. We revealed a novel role for NuclErbB-2 as an independent prognostic factor of poor clinical outcome in MembErbB-2-positive breast tumors. Our work indicates that patients presenting NuclErbB-2 may need new therapeutic strategies involving specific blockage of ErbB-2 nuclear migration

  3. Clinical relevance of ErbB-2/HER2 nuclear expression in breast cancer

    Directory of Open Access Journals (Sweden)

    Schillaci Roxana

    2012-02-01

    Full Text Available Abstract Background The biological relevance of nuclear ErbB-2/HER2 (NuclErbB-2 presence in breast tumors remains unexplored. In this study we assessed the clinical significance of ErbB-2 nuclear localization in primary invasive breast cancer. The reporting recommendations for tumor marker prognostic studies (REMARK guidelines were used as reference. Methods Tissue microarrays from a cohort of 273 primary invasive breast carcinomas from women living in Chile, a Latin American country, were examined for membrane (MembErbB-2 and NuclErbB-2 expression by an immunofluorescence (IF protocol we developed. ErbB-2 expression was also evaluated by immunohistochemistry (IHC with a series of antibodies. Correlation between NuclErbB-2 and MembErbB-2, and between NuclErbB-2 and clinicopathological characteristics of tumors was studied. The prognostic value of NuclErbB-2 in overall survival (OS was evaluated using Kaplan-Meier method, and Cox model was used to explore NuclErbB-2 as independent prognostic factor for OS. Results The IF protocol we developed showed significantly higher sensitivity for detection of NuclErbB-2 than IHC procedures, while its specificity and sensitivity to detect MembErbB-2 were comparable to those of IHC procedures. We found 33.6% NuclErbB-2 positivity, 14.2% MembErbB-2 overexpression by IF, and 13.0% MembErbB-2 prevalence by IHC in our cohort. We identified NuclErbB-2 positivity as a significant independent predictor of worse OS in patients with MembErbB-2 overexpression. NuclErbB-2 was also a biomarker of lower OS in tumors that overexpress MembErbB-2 and lack steroid hormone receptors. Conclusions We revealed a novel role for NuclErbB-2 as an independent prognostic factor of poor clinical outcome in MembErbB-2-positive breast tumors. Our work indicates that patients presenting NuclErbB-2 may need new therapeutic strategies involving specific blockage of ErbB-2 nuclear migration.

  4. Photoenhanced uptakes of NO2 by indoor surfaces: A new HONO source

    Science.gov (United States)

    Gligorovski, S.; Bartolomei, V.; Soergel, M.; Gomez Alvarez, E.; Zetzsch, C.; Wortham, H.

    2012-12-01

    conversion of NO2 to HONO on lacquer surfaces and on white wall paints is substantially enhanced in the presence of light and at higher relative humidity (RH = 60%). In runs carried out applying experimental conditions typically found indoors, i.e., NO2 mixing ratios of 25 ppb and 60% RH%, the observed NO2 uptakes on a surface coated with lacquer and paint showed an enhancement of one order of magnitude in the presence of light as compared to the uptake observed in the dark. Our results indicate, contrary to other study that claimed that humidity does not influence the NO2 reactions with adsorbed organics, that actually both postulated HONO sources combined i.e. heterogeneous NO2 reactions with adsorbed organics (photosensitizers) in presence of elevated humidity leads to even more pronounced HONO production. Reference: 1. M., Sleiman, L. A., Gundel, J. F., Pankow, P., Jacob, B. C., Singer, H., Destaillats, P. Natl. Acad. Sci. USA, 107, 6576 (2010). 2. B. J. Finlayson-Pitts, L. M. Wingen, A. L. Sumner, D. Syomin, K. A. Ramazan, Phys. Chem. Chem. Phys. 5, 223 (2003). 3. K., Stemmler, M., Ammann, C., Donders, J., Kleffmann, C., George, Nature 440, 195 (2006). 4. E. Gomez Alvarez, H. Wortham, R. Strekowski, C. Zetzsch, S. Gligorovski, Environ. Sci. Technol., 46, 1955 (2012).

  5. The B(E2;4^+1->2^+1) / B(E2;2^+1->0^+1) Ratio in Even-Even Nuclei

    Science.gov (United States)

    Loelius, C.; Sharon, Y. Y.; Zamick, L.; G"Urdal, G.

    2009-10-01

    We considered 207 even-even nuclei throughout the chart of nuclides for which the NNDC Tables had data on the energies and lifetimes of the 2^+1 and 4^+1 states. Using these data we calculated for each nucleus the electric quadrupole transition strengths B(E2;4^+1->2^+1) and B(E2;2^+1->0^+1), as well as their ratio. The internal conversion coefficients were obtained by using the NNDC HSICC calculator. For each nucleus we plotted the B(E2) ratio against A, N, and Z. We found that for close to 90% of the nuclei considered the ratio had values between 0.5 and 2.5. Most of the outliers had magic numbers of protons or neutrons. Our ratio results were compared with the theoretical predictions for this ratio by different models--10/7 in the rotational model and 2 in the simplest vibrational model. In the rotational regions (for 150 220) the ratios were indeed close to 10/7. For the few nuclei thought to be vibrational the ratios were usually less than 2. Otherwise, we got a wide scatter of ratio values. Hence other models, including the NpNn scheme, must be considered in interpreting these results.

  6. Function of brain α2B-adrenergic receptor characterized with subtype-selective α2B antagonist and KO mice.

    Science.gov (United States)

    Luhrs, Lauren; Manlapaz, Cynthia; Kedzie, Karen; Rao, Sandhya; Cabrera-Ghayouri, Sara; Donello, John; Gil, Daniel

    2016-12-17

    Noradrenergic signaling, through the α 2A and α 2C adrenergic receptors modulates the cognitive and behavioral symptoms of disorders such as schizophrenia, attention deficit hyperactivity disorder (ADHD), and addiction. However, it is unknown whether the α 2B receptor has any significant role in CNS function. The present study elucidates the potential role of the α 2B receptor in CNS function via the discovery and use of the first subtype-selective α 2B antagonist (AGN-209419), and behavioral analyses of α-receptor knockout (KO) mice. Using AGN-209419 as radioligand, α 2B receptor binding sites were identified within the olfactory bulb, cortex, thalamus, cerebellum, and striatum. Based on the observed expression patterns of α 2 subtypes in the brain, we compared α 2B KO, α 2A KO and α 2C KO mice behavioral phenotypes with their respective wild-type lines in anxiety (plus maze), compulsive (marble burying), and sensorimotor (prepulse inhibition) tasks. α 2B KO mice exhibited increased marble burying and α 2C KO mice exhibited an increased startle response to a pulse stimulus, but otherwise intact prepulse inhibition. To further explore compulsive behavior, we evaluated novelty-induced locomotor hyperactivity and found that α 2B KO and α 2C KO mice exhibited increased locomotion in the open field. Interestingly, when challenged with amphetamine, α 2C KO mice increased activity at lower doses relative to either α 2A KO or WT mice. However, α 2B KO mice exhibited stereotypy at doses of amphetamine that were only locomotor stimulatory to all other genotypes. Following co-administration of AGN-209419 with low-dose amphetamine in WT mice, stereotypy was observed, mimicking the α 2B KO phenotype. These findings suggest that the α 2B receptor is involved in CNS behaviors associated with sensorimotor gating and compulsivity, and may be therapeutically relevant for disorders such as schizophrenia, ADHD, post-traumatic stress disorder, addiction, and

  7. Marketing-sales interface configurations in B2B firms

    NARCIS (Netherlands)

    Biemans, Wim G.; Brencic, Maja Makovec; Malshe, Avinash; Makovec Brenciv, M.

    As the body of knowledge on marketing-sales interface expands, there is a greater need to investigate the specific aspects of marketing-sales configurations in B2B firms. Using a qualitative methodology and interview data collected from over 100 sales and marketing professionals from the US, The

  8. Whiting 1: Confirmation of its accretion by the Milky Way

    Directory of Open Access Journals (Sweden)

    Carballo-Bello Julio A.

    2017-01-01

    Full Text Available We investigate the association of Whiting 1 with the Sagittarius tidal stream by obtaining radial velocities for a sample of 101 stars observed with VIMOS. Our results reveal the presence of a component of the Sagittarius tidal stream with a radial velocity – and distance – compatible with that of the globular cluster. Therefore, we conclude that Whiting1 was formed in the interior of the Sagittarius dwarf spheroidal galaxy and later accreted by the Milky Way. In addition, our data also reveal the detection for the first time of an ancient wrap of the Sagittarius tidal stream along the same line-of-sight and at the same heliocentric distance.

  9. EUDAT B2FIND : A Cross-Discipline Metadata Service and Discovery Portal

    Science.gov (United States)

    Widmann, Heinrich; Thiemann, Hannes

    2016-04-01

    The European Data Infrastructure (EUDAT) project aims at a pan-European environment that supports a variety of multiple research communities and individuals to manage the rising tide of scientific data by advanced data management technologies. This led to the establishment of the community-driven Collaborative Data Infrastructure that implements common data services and storage resources to tackle the basic requirements and the specific challenges of international and interdisciplinary research data management. The metadata service B2FIND plays a central role in this context by providing a simple and user-friendly discovery portal to find research data collections stored in EUDAT data centers or in other repositories. For this we store the diverse metadata collected from heterogeneous sources in a comprehensive joint metadata catalogue and make them searchable in an open data portal. The implemented metadata ingestion workflow consists of three steps. First the metadata records - provided either by various research communities or via other EUDAT services - are harvested. Afterwards the raw metadata records are converted and mapped to unified key-value dictionaries as specified by the B2FIND schema. The semantic mapping of the non-uniform, community specific metadata to homogenous structured datasets is hereby the most subtle and challenging task. To assure and improve the quality of the metadata this mapping process is accompanied by • iterative and intense exchange with the community representatives, • usage of controlled vocabularies and community specific ontologies and • formal and semantic validation. Finally the mapped and checked records are uploaded as datasets to the catalogue, which is based on the open source data portal software CKAN. CKAN provides a rich RESTful JSON API and uses SOLR for dataset indexing that enables users to query and search in the catalogue. The homogenization of the community specific data models and vocabularies enables not

  10. Analysis list: Gtf2b [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Gtf2b Blood,Cardiovascular,Liver + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/m...m9/target/Gtf2b.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Gtf2b.5.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/target/Gtf2b.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Gtf2b.Blo...od.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Gtf2b.Cardiovascular.t...sv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Gtf2b.Liver.tsv http://dbarchive.biosciencedbc.jp/kyu

  11. The nido-osmaboranes [2,2,2-(CO)(PPh(3))(2)-nido-2-OsB(5)H(9)] and [6,6,6-(CO)(PPh(3))(2)-nido-6-OsB(9)H(13)].

    Science.gov (United States)

    Bould, J; Kennedy, J D; Thomas, R L; Rath, N P; Barton, L

    2001-11-01

    The structural characterization of the osmahexaborane 2-carbonyl-2,2-bis(triphenylphosphine)-nido-2-osmahexaborane(9), [Os(B(5)H(9))(C(18)H(15)P)(2)(CO)], (I), a metallaborane analogue of B(6)H(10), confirms the structure proposed from NMR spectroscopy. The structure of the osmadecaborane 6-carbonyl-6,6-bis(triphenylphosphine)-nido-6-osmadecaborane(13), [Os(B(9)H(13))(C(18)H(15)P)(2)(CO)], (IV), is similarly confirmed. The short basal B-B distance of 1.652 (8) A in (I), not bridged by an H atom, mirrors that in the parent hexaborane(10) [1.626 (4) A].

  12. Magnetic anisotropy of YNi2B2C single crystals

    International Nuclear Information System (INIS)

    Baran, M.; Gladczuk, L.; Gorecka, J.; Szymczak, H.; Szymczak, R.; Drzazga, Z.; Winiarska, H.

    1994-01-01

    Reversible and irreversible magnetization processes in YNi 2 B 2 C single crystal have been measured and analysed in terms of existing theories. Performed measurements suggest that anisotropy of the effective mass in YNi 2 B 2 C superconductor is rather small and similar to that observed in conventional superconductors. Effect of hydrostatic pressure on T c is shown to be typical of low-temperature superconductors. It is suggested that the layered structure of YNi 2 B 2 C has some effect on the irreversible magnetization processes observed in this superconductor. ((orig.))

  13. Intelligent Information Integration in B2B Electronic Commerce

    NARCIS (Netherlands)

    Fensel, Dieter; Omelayenko, Borys; Ding, Ying; Klein, Michel; Flett, Alan; Schulten, Ellen; Botquin, Guy; Brown, Mike; Dabiri, Gloria

    2002-01-01

    Internet and web technology penetrates many aspects of our daily life. Its importance as a medium for business transactions will grow exponentially during the next few years. In terms of the involved market volume, the B2B area will hereby be the most interesting area. Also, it will be the place,

  14. Densification, characterization and oxidation studies of novel TiB{sub 2}+EuB{sub 6} compounds

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, T.S.R.Ch., E-mail: murthi@barc.gov.in [Materials Group, Bhabha Atomic Research Centre, Mumbai (India); Sonber, J.K.; Vishwanadh, B. [Materials Group, Bhabha Atomic Research Centre, Mumbai (India); Nagaraj, A. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Mumbai (India); Sairam, K.; Bedse, R.D.; Chakravartty, J.K. [Materials Group, Bhabha Atomic Research Centre, Mumbai (India)

    2016-06-15

    TiB{sub 2}+EuB{sub 6} ceramic samples with different EuB{sub 6} contents were fabricated using hot -pressing technique. The introduction of EuB{sub 6} promoted the sinterability, fracture toughness and oxidation resistance of TiB{sub 2}. 98.7% TD achieved by adding 2.5% EuB{sub 6} to TiB{sub 2} by hot pressing at a relatively low temperature of 1750 °C, 35 MPa, 1h. Formation of complete solid solution of TiB{sub 2}+EuB{sub 6} observed for all the samples by XRD, EDS and EBSD. Hardness of all samples is measured in the range of 24–27 GPa ∼50% higher fracture toughness value of 5.2 MPa m{sup 1/2} was obtained in the 2.5% EuB{sub 6} contained sample compared to monolithic TiB{sub 2}. Enhancement of oxidation resistance of TiB{sub 2} was observed by EuB{sub 6} addition due to the formation of EuBO{sub 3} and Eu{sub 2}O{sub 3}. Oxidized cross section of TiB{sub 2}+EuB{sub 6} sample was measured as 340 μm, which is ∼35% less than that of monolithic TiB{sub 2} (520 μm), after oxidation at 1400 °C for 8h. - Highlights: • 98.7% TD achieved by adding 2.5% EuB{sub 6} to TiB{sub 2}. • Formation of complete solid solution of TiB{sub 2}+EuB{sub 6} observed. • Fracture toughness value of 5.2 MPa m{sup 1/2} was obtained in the TiB{sub 2}+2.5% EuB{sub 6}. • EuBO{sub 3} and Eu{sub 2}O{sub 3} are enhanced the oxidation resistance of TiB{sub 2} + EuB{sub 6} compound. • Oxide layer thicknesses of TiB{sub 2} and TiB{sub 2}+EuB{sub 6} are 520 μm and 340 μm respectively.

  15. Open Source Information in Support of Safeguards

    International Nuclear Information System (INIS)

    Christopher, G.

    2015-01-01

    Open source techniques are an increasingly important tool for in safeguards. From social networking sites, such as Linkedin, to B2B portals like Alibaba, there are large open source databases that touch all aspects of the nuclear fuel cycle, from goods to scientists. This is in addition to the wealth of more traditional open source tools such as search engines. In this paper we focus on the potential of B2B sites to provide dual use goods for use in the nuclear fuel cycle. We will discuss the availability of these items as well as the frequency and content of tenders. As many of the largest sites—by traffic and content—are in Asia we will examine the potential of these sites to provide goods used in the nuclear fuel cycle. (author)

  16. Fabrication of sandwich-type MgB{sub 2}/Boron/MgB{sub 2} Josephson junctions with rapid annealing method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Song; Wang, Xu; Ma, Junli; Cui, Ruirui; Deng, Chaoyong, E-mail: cydeng@gzu.edu.cn

    2015-11-15

    Sandwich-type MgB{sub 2}/Boron/MgB{sub 2} Josephson junctions were fabricated using magnetron sputtering system. The rapid-anneal process was adopted to replace traditional way of annealing, trying to solve the problem of interdiffusion and oxidation with multilayer films. The boron film was used as barrier layer to avoid the introduction of impurities and improve reproducibility of the junctions. The bottom MgB{sub 2} thin films deposited on c-plane sapphire substrate exhibits a critical temperature T{sub C} of 37.5 K and critical current density J{sub C} at 5 K of 8.7 × 10{sup 6} A cm{sup −2}. From the XRD pattern, the bottom MgB{sub 2} thin film shows c-axis orientation, whereas the top MgB{sub 2} became polycrystalline as Boron barrier layer grown thicker. Therefore, all junction samples show lower T{sub C} than single MgB{sub 2} thin film. The junctions exhibit excellent quasiparticle characteristics with ideal dependence on temperature and Boron barrier thickness. Subharmonic gap structure was appeared in conductance characteristics, which was attributed to the multiple Andreev reflections (MAR). The result demonstrates great promise of this new fabrication technology for MgB{sub 2} Josephson junction fabrication. - Highlights: • Sandwich-type MgB{sub 2}/Boron/MgB{sub 2} Josephson junctions were fabricated. • The junctions were annealed after deposition with the rapid-anneal process. • The highest critical current is 25.3 mA at 5 K and remains non-zero near 25 K. • Subharmonic gap features can be observed in the dI/dV – V curves.

  17. Dynamical structure of hadron emission sources

    International Nuclear Information System (INIS)

    Zhao Xi; Huang Bangrong; Zhao Shusong

    2000-01-01

    NA22 experimental data of the triplet seagull effects show that the Doppler effects of the hadron emission sources exist exactly in the hadron-hadron collisions. Every source possesses the same average energy (CMS) approximately. The collective seagull effects can be also explained by the (aQ) ν K ν (aQ) distributions (Generalized functions). The dynamical structure of a hadron emission source is described by the (aQ) ν K ν (aQ) distributions. The anomalous dimensions of the pionic quantum fields are γ B (g R ) = - 0.045 +- 0.012, which control the singularities of the production amplitude in quantum field theory. The mathematical parameter ε = 4-D (the dimension D of space time) in the Feynman integrals can be replaced by the anomalous γ B (g R ) of the quantum fields for the regularization. (-2γ B (g R )↔ε/2 1/ln(Λ 2 /m 2 )Λ→∞)

  18. Nido-Carborane building-block reagents. 2. Bulky-substituent (alkyl)2C2B4H6 derivatives and (C6H5)2C2B4H6: synthesis and properties

    International Nuclear Information System (INIS)

    Boyter, H.A. Jr.; Grimes, R.N.

    1988-01-01

    The preparation and chemistry of nido-2,3-R 2 C 2 C 2 B 4 H 6 carboranes in which R is n-butyl, isopentyl, n-hexyl, and phenyl was investigated in order to further assess the steric and electronic influence of the R groups on the properties of the nido-C 2 B 4 cage, especially with respect to metal complexation at the C 2 B 3 face and metal-promoted oxidative fusion. The three dialkyl derivatives were prepared from the corresponding dialkylacetylenes via reaction with B 5 H 9 and triethylamine, but the diphenyl compound could not be prepared in this manner and was obtained instead in a thermal reaction of B 5 H 9 with diphenylacetylene in the absence of amine. All four carboranes are readily bridge-deprotonated by NaH in THF, and the anions of the dialkyl species, on treatment with FeCl 2 and air oxidation, generate the respective R 4 C 4 B 8 H 8 carborane fusion products were R = n-C 4 H 9 , i-C 5 H 11 or n-C 6 H 13 . The diphenylcarborane anion Ph 2 C 2 B 4 H 5 - did not form detectable metal complexes with Fe 2+ , Co 2+ , or Ni 2+ , and no evidence of a Ph 4 C 4 B 8 H 8 fusion product has been found. Treatment of Ph 2 C 2 B 4 H 6 with Cr(CO) 6 did not lead to metal coordination of the phenyl rings, unlike (PhCH 2 ) 2 C 2 B 4 H 6 , which had previously been shown to form mono- and bis(tricarbonylchromium) complexes. However, the reaction of Ph 2 C 2 B 4 H 5 - , CoCl 2 , and (PhPCH 2 ) 2 did give 1,1-(Ph 2 PCH 2 ) 2 -1-Cl-1,2,3-Co(Ph 2 C 2 B 4 H 4 ), the only case in which metal complexation of the diphenylcarborane was observed. 14 references, 3 figures, 3 tables

  19. TFAP2B mutation and dental anomalies.

    Science.gov (United States)

    Tanasubsinn, Natchaya; Sittiwangkul, Rekwan; Pongprot, Yupada; Kawasaki, Katsushige; Ohazama, Atsushi; Sastraruji, Thanapat; Kaewgahya, Massupa; Kantaputra, Piranit Nik

    2017-08-01

    Mutations inTFAP2B has been reported in patients with isolated patent ductus arteriosus (PDA) and Char syndrome. We performed mutation analysis of TFAP2B in 43 patients with isolated PDA, 7 patients with PDA with other congenital heart defects and 286 patients with isolated tooth agenesis with or without other dental anomalies. The heterozygous c.1006G>A mutation was identified in 20 individuals. Those mutation carriers consisted of 1 patient with term PDA (1/43), 16 patients with isolated tooth agenesis with or without other dental anomalies (16/286; 5.6%), 1 patient with PDA and severe valvular aortic stenosis and tooth agenesis (1/4) and 2 normal controls (2/100; 1%). The mutation is predicted to cause an amino-acid substitution p.Val336Ile in the TFAP2B protein. Tfap2b expression during early mouse tooth development supports the association of TFAP2B mutation and dental anomalies. It is hypothesized that this incidence might have been the result of founder effect. Here we report for the first time that TFAP2B mutation is associated with tooth agenesis, microdontia, supernumerary tooth and root maldevelopment. In addition, we also found that TFAP2B mutations, the common causes of PDA in Caucasian, are not the common cause of PDA in Thai population.

  20. COSIMA B2B - sales automation for e-procurement

    OpenAIRE

    Döring, Sven

    2004-01-01

    COSIMA B2B - sales automation for e-procurement / W. Kießling, S. Fischer, S. Döring. - In: International Conference on E-Commerce Technology : Proceedings / IEEE International Conference on E-Commerce Technology, CEC 2004 : 6 - 9 July 2004, San Diego, California / ed. by Martin Bichler ... - Los Alamitos, Calif. [u.a.] : IEEE Computer Society, 2004. - S. 59-68

  1. Advanced Neutron Source Cross Section Libraries (ANSL-V): ENDF/B-V based multigroup cross-section libraries for advanced neutron source (ANS) reactor studies

    International Nuclear Information System (INIS)

    Ford, W.E. III; Arwood, J.W.; Greene, N.M.; Moses, D.L.; Petrie, L.M.; Primm, R.T. III; Slater, C.O.; Westfall, R.M.; Wright, R.Q.

    1990-09-01

    Pseudo-problem-independent, multigroup cross-section libraries were generated to support Advanced Neutron Source (ANS) Reactor design studies. The ANS is a proposed reactor which would be fueled with highly enriched uranium and cooled with heavy water. The libraries, designated ANSL-V (Advanced Neutron Source Cross Section Libraries based on ENDF/B-V), are data bases in AMPX master format for subsequent generation of problem-dependent cross-sections for use with codes such as KENO, ANISN, XSDRNPM, VENTURE, DOT, DORT, TORT, and MORSE. Included in ANSL-V are 99-group and 39-group neutron, 39-neutron-group 44-gamma-ray-group secondary gamma-ray production (SGRP), 44-group gamma-ray interaction (GRI), and coupled, 39-neutron group 44-gamma-ray group (CNG) cross-section libraries. The neutron and SGRP libraries were generated primarily from ENDF/B-V data; the GRI library was generated from DLC-99/HUGO data, which is recognized as the ENDF/B-V photon interaction data. Modules from the AMPX and NJOY systems were used to process the multigroup data. Validity of selected data from the fine- and broad-group neutron libraries was satisfactorily tested in performance parameter calculations

  2. Thermodynamics of TiB2 from Ti-B-N studies

    International Nuclear Information System (INIS)

    Yurick, T.J.; Spear, K.E.

    1979-01-01

    Thermodynamic data for the formation of TiB 2 have been extracted from equilibrium pressure-temperature-composition investigations in the ternary Ti-B-N system. The value ΔH 0 sub(f,298)(TiB 2 ) = -72.7 +- 1.6 kcal/mole determined from a 3rd law analysis of the present results does not agree either with standard reference book values of about -67 kcal/mole or with later calorimetric results of about -77 kcal/mole. The uncertainty listed with the value reported in this paper is a result of a detailed error analysis on possible random and systematic errors encountered in our investigation. (orig.) [de

  3. Sagittarius

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    (the Archer; abbrev. Sgr, gen. Sagittarii; area 867 sq. deg.) A southern zodiacal constellation which lies between Ophiuchus and Capricornus, and culminates at midnight in early July. Its origin dates back to Sumerian times, when it was identified with Nergal, a god of war, but today it is associated with Crotus, son of the Greek god Pan and the inventor of archery, and it is shown on early celes...

  4. C3-PRO: Connecting ResearchKit to the Health System Using i2b2 and FHIR.

    Directory of Open Access Journals (Sweden)

    Pascal B Pfiffner

    Full Text Available A renewed interest by consumer information technology giants in the healthcare domain is focused on transforming smartphones into personal health data storage devices. With the introduction of the open source ResearchKit, Apple provides a framework for researchers to inform and consent research subjects, and to readily collect personal health data and patient reported outcomes (PRO from distributed populations. However, being research backend agnostic, ResearchKit does not provide data transmission facilities, leaving research apps disconnected from the health system. Personal health data and PROs are of the most value when presented in context along with health system data. Our aim was to build a toolchain that allows easy and secure integration of personal health and PRO data into an open source platform widely adopted across 140 academic medical centers. We present C3-PRO: the Consent, Contact, and Community framework for Patient Reported Outcomes. This open source toolchain connects, in a standards-compliant fashion, any ResearchKit app to the widely-used clinical research infrastructure Informatics for Integrating Biology and the Bedside (i2b2. C3-PRO leverages the emerging health data standard Fast Healthcare Interoperability Resources (FHIR.

  5. C3-PRO: Connecting ResearchKit to the Health System Using i2b2 and FHIR.

    Science.gov (United States)

    Pfiffner, Pascal B; Pinyol, Isaac; Natter, Marc D; Mandl, Kenneth D

    2016-01-01

    A renewed interest by consumer information technology giants in the healthcare domain is focused on transforming smartphones into personal health data storage devices. With the introduction of the open source ResearchKit, Apple provides a framework for researchers to inform and consent research subjects, and to readily collect personal health data and patient reported outcomes (PRO) from distributed populations. However, being research backend agnostic, ResearchKit does not provide data transmission facilities, leaving research apps disconnected from the health system. Personal health data and PROs are of the most value when presented in context along with health system data. Our aim was to build a toolchain that allows easy and secure integration of personal health and PRO data into an open source platform widely adopted across 140 academic medical centers. We present C3-PRO: the Consent, Contact, and Community framework for Patient Reported Outcomes. This open source toolchain connects, in a standards-compliant fashion, any ResearchKit app to the widely-used clinical research infrastructure Informatics for Integrating Biology and the Bedside (i2b2). C3-PRO leverages the emerging health data standard Fast Healthcare Interoperability Resources (FHIR).

  6. 49 CFR Appendix B to Part 564 - Information To Be Submitted for Long Life Replaceable Light Sources of Limited Definition

    Science.gov (United States)

    2010-10-01

    ...—Information To Be Submitted for Long Life Replaceable Light Sources of Limited Definition I. Filament or... Source that Operates With a Ballast and Rated Life of the Light Source/Ballast Combination. A. Maximum power (in watts). B. Luminous Flux (in lumens). C. Rated laboratory life of the light source/ballast...

  7. Crystal Growth, Structures, and Properties of the Complex Borides, LaOs 2 Al 2 B and La 2 Os 2 AlB 2

    Energy Technology Data Exchange (ETDEWEB)

    Bugaris, Daniel E.; Han, Fei; Im, Jino; Chung, Duck Young; Freeman, Arthur J.; Kanatzidis, Mercouri G.

    2015-08-17

    Single crystals of two novel quaternary metal borides, LaOs2Al2B and La2Os2AlB2, have been grown from La/Ni eutectic fluxes. LaOs2Al2B crystallizes in tetragonal space group P4/mmm with the CeCr2Si2C-type structure, and lattice parameters a = 4.2075(6) angstrom and c = 5.634(1) angstrom. La2Os2AlB2 exhibits a new crystal structure in monoclinic space group C2/c with lattice parameters a = 16.629(3) angstrom, b = 6.048(1) angstrom, c = 10.393(2) angstrom, and beta = 113.96(3)degrees. Both structures are three-dimensional frameworks with unusual coordination (for solid-state compounds) of the boron atoms by transition metal atoms. The boron atom is square planar in LaOs2Al2B, whereas it exhibits linear and T-shaped geometries in La2Os2AlB2. Electrical resistivity measurements reveal poor metal behavior (rho(30)0 (K) similar to 900 mu Omega cm) for La2Os2AlB2, consistent with the electronic band structure calculations, which also predict a metallic character for LaOs2Al2B.

  8. 32 CFR 806b.2 - Basic guidelines.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Basic guidelines. 806b.2 Section 806b.2 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ADMINISTRATION PRIVACY ACT PROGRAM Overview of the Privacy Act Program § 806b.2 Basic guidelines. This part implements the Privacy Act of 1974...

  9. The ρ(ω)B*(B) interaction and states of J = 0, 1, 2

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Soler, P.; Sun, Zhi-Feng; Oset, E. [Centro Mixto Universidad de Valencia-CSIC Institutos de Investigacion de Paterna, Departamento de Fisica Teorica and IFIC, Valencia (Spain); Nieves, J. [Centro Mixto Universidad de Valencia-CSIC Institutos de Investigacion de Paterna, IFIC, Valencia (Spain)

    2016-02-15

    In this work, we study systems composed of a ρ/ω and B* meson pair. We find three bound states in isospin, spin-parity channels (1/2, 0{sup +}), (1/2, 1{sup +}), and (1/2, 2{sup +}). The state with J = 2 can be a good candidate for the B{sub 2}{sup *} (5747). We also study the ρB system, and a bound state with mass 5728 MeV and width around 20 MeV is obtained, which can be identified with the B1(5721) resonance. In the case of I = 3/2, one obtains repulsion and, thus, no exotic (molecular) mesons in this sector are generated in the approach. (orig.)

  10. Analysis list: GTF2B [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available GTF2B Blood,Uterus + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/GT...F2B.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/GTF2B.5.tsv http://dbarchive.biosciencedbc....jp/kyushu-u/hg19/target/GTF2B.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/GTF2B.Blood.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/hg19/colo/GTF2B.Uterus.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/hg19/colo/Blood.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/Uterus.gml ...

  11. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XIX. TOMOGRAPHY OF MILKY WAY SUBSTRUCTURES IN THE NGVS FOOTPRINT

    Energy Technology Data Exchange (ETDEWEB)

    Lokhorst, Deborah; Starkenburg, Else; Navarro, Julio F. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1, Canada (Canada); McConnachie, Alan W.; Ferrarese, Laura; Côté, Patrick; Gwyn, Stephen D. J. [National Research Council, Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Liu, Chengze [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Peng, Eric W. [Department of Astronomy, Peking University, Beijing 100871 (China); Cuillandre, Jean-Charles [CEA/IRFU/SAP, Laboratoire AIM Paris-Saclay, CNRS/INSU, Université Paris Diderot, Observatoire de Paris, PSL Research University, F-91191 Gif-sur-Yvette Cedex (France); Guhathakurta, Puragra, E-mail: dml@uvic.ca [Department of Astronomy and Astrophysics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2016-03-10

    The Next Generation Virgo Cluster Survey (NGVS) is a deep u*giz survey targeting the Virgo Cluster of galaxies at 16.5 Mpc. This survey provides high-quality photometry over an ∼100 deg{sup 2} region straddling the constellations of Virgo and Coma Berenices. This sightline through the Milky Way is noteworthy in that it intersects two of the most prominent substructures in the Galactic halo: the Virgo overdensity (VOD) and Sagittarius stellar stream (close to its bifurcation point). In this paper, we use deep u*gi imaging from the NGVS to perform tomography of the VOD and Sagittarius stream using main-sequence turnoff (MSTO) stars as a halo tracer population. The VOD, whose centroid is known to lie at somewhat lower declinations (α ∼ 190°, δ ∼ −5°) than is covered by the NGVS, is nevertheless clearly detected in the NGVS footprint at distances between ∼8 and 25 kpc. By contrast, the Sagittarius stream is found to slice directly across the NGVS field at distances between 25 and 40 kpc, with a density maximum at ≃35 kpc. No evidence is found for new substructures beyond the Sagittarius stream, at least out to a distance of ∼90 kpc—the largest distance to which we can reliably trace the halo using MSTO stars. We find clear evidence for a distance gradient in the Sagittarius stream across the ∼30° of sky covered by the NGVS and its flanking fields. We compare our distance measurements along the stream with those predicted by leading stream models.

  12. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XIX. TOMOGRAPHY OF MILKY WAY SUBSTRUCTURES IN THE NGVS FOOTPRINT

    International Nuclear Information System (INIS)

    Lokhorst, Deborah; Starkenburg, Else; Navarro, Julio F.; McConnachie, Alan W.; Ferrarese, Laura; Côté, Patrick; Gwyn, Stephen D. J.; Liu, Chengze; Peng, Eric W.; Cuillandre, Jean-Charles; Guhathakurta, Puragra

    2016-01-01

    The Next Generation Virgo Cluster Survey (NGVS) is a deep u*giz survey targeting the Virgo Cluster of galaxies at 16.5 Mpc. This survey provides high-quality photometry over an ∼100 deg 2 region straddling the constellations of Virgo and Coma Berenices. This sightline through the Milky Way is noteworthy in that it intersects two of the most prominent substructures in the Galactic halo: the Virgo overdensity (VOD) and Sagittarius stellar stream (close to its bifurcation point). In this paper, we use deep u*gi imaging from the NGVS to perform tomography of the VOD and Sagittarius stream using main-sequence turnoff (MSTO) stars as a halo tracer population. The VOD, whose centroid is known to lie at somewhat lower declinations (α ∼ 190°, δ ∼ −5°) than is covered by the NGVS, is nevertheless clearly detected in the NGVS footprint at distances between ∼8 and 25 kpc. By contrast, the Sagittarius stream is found to slice directly across the NGVS field at distances between 25 and 40 kpc, with a density maximum at ≃35 kpc. No evidence is found for new substructures beyond the Sagittarius stream, at least out to a distance of ∼90 kpc—the largest distance to which we can reliably trace the halo using MSTO stars. We find clear evidence for a distance gradient in the Sagittarius stream across the ∼30° of sky covered by the NGVS and its flanking fields. We compare our distance measurements along the stream with those predicted by leading stream models

  13. Photocatalytic applications of Cr{sub 2}S{sub 3} synthesized from single and multi-source precursors

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, Wajid [Department of Chemistry, Quaid-i-Azam University, 45320, Islamabad (Pakistan); Badshah, Amin, E-mail: aminbadshah@qau.edu.pk [Department of Chemistry, Quaid-i-Azam University, 45320, Islamabad (Pakistan); Hussain, Raja Azadar; Imtiaz-ud-Din [Department of Chemistry, Quaid-i-Azam University, 45320, Islamabad (Pakistan); Aleem, Muhammad Adeel [The Pakistan Institute of Engineering and Applied Sciences (PIEAS) (Pakistan); Bahadur, Ali [Department of Chemistry, Quaid-i-Azam University, 45320, Islamabad (Pakistan); Iqbal, Shahid [School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing, 100049 (China); Farooq, Muhammad Umar; Ali, Hassan [Department of Chemistry, Quaid-i-Azam University, 45320, Islamabad (Pakistan)

    2017-06-15

    Most of the material research work is pertinent to the synthesis of transition-metal sulfides nanoparticles but here the studies are limited to the synthesis of chromium sulfide. However, the preparation method, presented in this work, may be extended to other metal chalcogenides nanoparticles for various potential applications. The ligand (precursor), 1-(2-chloro-4-nitrophenyl)-3,3-chlorobenzoyl and Cr{sub 2}S{sub 3} have been synthesized initially from single source precursor and then from multi source precursors. The target was to alter the morphologies of nanomaterial while altering the synthetic route and that was successfully achieved. Chromium sulfide nano-rods were synthesized using single source precursors while nanoparticles were fabricated using multi source precursors. Characterization were carried out through {sup 1}H and {sup 13}C NMR, scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction microscopy (PXRD), energy dispersive X-ray spectroscopy (EDX), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM). Our objective is to change the morphologies by changing the synthetic route so that is why further applications were done only for multi-source product, denying single source product. The metal sulfides nanoparticles exhibit higher activity than their bulk material for the photocatalytic degradation of organic dyes under visible-light irradiation. So, photocatalytic activity was successfully achieved under direct sunlight against five different cationic and anionic organic dyes including malachite green (MG), methylene blue (MB), rhodamine B (RhB), methyl violet (MV) and methyl orange (MO). These organic dyes MV, MG, MB, and RB were almost diminished or decolorized by Cr{sub 2}S{sub 3} within 110, 90, 100, and 130, minutes, respectively expect MO. - Highlights: • Synthesis of Cr{sub 2}S{sub 3} from single and multisource precursors is

  14. Pseudo-dynamic source modelling with 1-point and 2-point statistics of earthquake source parameters

    KAUST Repository

    Song, S. G.

    2013-12-24

    Ground motion prediction is an essential element in seismic hazard and risk analysis. Empirical ground motion prediction approaches have been widely used in the community, but efficient simulation-based ground motion prediction methods are needed to complement empirical approaches, especially in the regions with limited data constraints. Recently, dynamic rupture modelling has been successfully adopted in physics-based source and ground motion modelling, but it is still computationally demanding and many input parameters are not well constrained by observational data. Pseudo-dynamic source modelling keeps the form of kinematic modelling with its computational efficiency, but also tries to emulate the physics of source process. In this paper, we develop a statistical framework that governs the finite-fault rupture process with 1-point and 2-point statistics of source parameters in order to quantify the variability of finite source models for future scenario events. We test this method by extracting 1-point and 2-point statistics from dynamically derived source models and simulating a number of rupture scenarios, given target 1-point and 2-point statistics. We propose a new rupture model generator for stochastic source modelling with the covariance matrix constructed from target 2-point statistics, that is, auto- and cross-correlations. Our sensitivity analysis of near-source ground motions to 1-point and 2-point statistics of source parameters provides insights into relations between statistical rupture properties and ground motions. We observe that larger standard deviation and stronger correlation produce stronger peak ground motions in general. The proposed new source modelling approach will contribute to understanding the effect of earthquake source on near-source ground motion characteristics in a more quantitative and systematic way.

  15. Enhanced B doping in CVD-grown GeSn:B using B δ-doping layers

    Science.gov (United States)

    Kohen, David; Vohra, Anurag; Loo, Roger; Vandervorst, Wilfried; Bhargava, Nupur; Margetis, Joe; Tolle, John

    2018-02-01

    Highly doped GeSn material is interesting for both electronic and optical applications. GeSn:B is a candidate for source-drain material in future Ge pMOS device because Sn adds compressive strain with respect to pure Ge, and therefore can boost the Ge channel performances. A high B concentration is required to obtain low contact resistivity between the source-drain material and the metal contact. To achieve high performance, it is therefore highly desirable to maximize both the Sn content and the B concentration. However, it has been shown than CVD-grown GeSn:B shows a trade-off between the Sn incorporation and the B concentration (increasing B doping reduces Sn incorporation). Furthermore, the highest B concentration of CVD-grown GeSn:B process reported in the literature has been limited to below 1 × 1020 cm-3. Here, we demonstrate a CVD process where B δ-doping layers are inserted in the GeSn layer. We studied the influence of the thickness between each δ-doping layers and the δ-doping layers process conditions on the crystalline quality and the doping density of the GeSn:B layers. For the same Sn content, the δ-doping process results in a 4-times higher B doping than the co-flow process. In addition, a B doping concentration of 2 × 1021 cm-3 with an active concentration of 5 × 1020 cm-3 is achieved.

  16. Supporting the diversity of B2B e-contracting processes

    NARCIS (Netherlands)

    Angelov, S.A.; Grefen, P.W.P.J.

    2008-01-01

    Contracts specify the rights and obligations of the contracting parties. Information technologies can make e-contracting more efficient and effective. A process model for flexible B2B e-contracting is proposed that separates concerns by distinguishing function and communication perspectives of

  17. The 4W framework for B2B E-contracting

    NARCIS (Netherlands)

    Angelov, S.; Grefen, P.W.P.J.

    2004-01-01

    Contracts are fundamental for the engagement of companies in commerce relations. B2B electronic contracting aims at improving the efficiency and effectiveness of the contracting process and at providing new opportunities to the contracting parties. Virtual enterprises, for example, can be

  18. Lattice Thermal Conductivity of Ultra High Temperature Ceramics (UHTC) ZrB2 and HfB2 from Atomistic Simulations

    Science.gov (United States)

    Lawson, John W.; Daw, Murray S.; Bauschlicher, Charles W.

    2012-01-01

    Ultra high temperature ceramics (UHTC) including ZrB2 and HfB2 have a number of properties that make them attractive for applications in extreme environments. One such property is their high thermal conductivity. Computational modeling of these materials will facilitate understanding of fundamental mechanisms, elucidate structure-property relationships, and ultimately accelerate the materials design cycle. Progress in computational modeling of UHTCs however has been limited in part due to the absence of suitable interatomic potentials. Recently, we developed Tersoff style parameterizations of such potentials for both ZrB2 and HfB2 appropriate for atomistic simulations. As an application, Green-Kubo molecular dynamics simulations were performed to evaluate the lattice thermal conductivity for single crystals of ZrB2 and HfB2. The atomic mass difference in these binary compounds leads to oscillations in the time correlation function of the heat current, in contrast to the more typical monotonic decay seen in monoatomic materials such as Silicon, for example. Results at room temperature and at elevated temperatures will be reported.

  19. Synthesis, Structure, Bonding, and Reactivity of Metal Complexes Comprising Diborane(4) and Diborene(2): [{Cp*Mo(CO)2 }2 {μ-η22 -B2 H4 }] and [{Cp*M(CO)2 }2 B2 H2 M(CO)4 ], M=Mo,W.

    Science.gov (United States)

    Mondal, Bijan; Bag, Ranjit; Ghorai, Sagar; Bakthavachalam, K; Jemmis, Eluvathingal D; Ghosh, Sundargopal

    2018-04-26

    The reaction of [(Cp*Mo) 2 (μ-Cl) 2 B 2 H 6 ] (1) with CO at room temperature led to the formation of the highly fluxional species [{Cp*Mo(CO) 2 } 2 {μ-η 22 -B 2 H 4 }] (2). Compound 2, to the best of our knowledge, is the first example of a bimetallic diborane(4) conforming to a singly bridged C s structure. Theoretical studies show that 2 mimics the Cotton dimolybdenum-alkyne complex [{CpMo(CO) 2 } 2 C 2 H 2 ]. In an attempt to replace two hydrogen atoms of diborane(4) in 2 with a 2e [W(CO) 4 ] fragment, [{Cp*Mo(CO) 2 } 2 B 2 H 2 W(CO) 4 ] (3) was isolated upon treatment with [W(CO) 5 ⋅thf]. Compound 3 shows the intriguing presence of [B 2 H 2 ] with a short B-B length of 1.624(4) Å. We isolated the tungsten analogues of 3, [{Cp*W(CO) 2 } 2 B 2 H 2 W(CO) 4 ] (4) and [{Cp*W(CO) 2 } 2 B 2 H 2 Mo(CO) 4 ] (5), which provided direct proof of the existence of the tungsten analogue of 2. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Magnetic Properties of New Triangular Lattice Magnets A${_4}$B'B${_2}$O$_{12}$

    OpenAIRE

    Rawl, Ryan; Lee, Minseong; Choi, Eun Sang; Li, Guang; Chen, Kuan-Wen; Baumbach, Ryan; Cruz, Clarina R. dela; Ma, Jie; Zhou, Haidong

    2017-01-01

    The geometrically frustrated two dimensional triangular lattice magnets A${_4}$B'B${_2}$O$_{12}$ (A = Ba, Sr, La; B' = Co, Ni, Mn; B = W, Re) have been studied by x-ray diffraction, AC and DC susceptibilities, powder neutron diffraction, and specific heat measurements. The results reveal that (i) the samples containing Co$^{2+}$ (effective spin-1/2) and Ni$^{2+}$ (spin-1) ions with small spin numbers exhibit ferromagnetic (FM) ordering while the sample containing Mn$^{2+}$ (spin-5/2) ions wit...

  1. Wearable energy sources based on 2D materials.

    Science.gov (United States)

    Yi, Fang; Ren, Huaying; Shan, Jingyuan; Sun, Xiao; Wei, Di; Liu, Zhongfan

    2018-05-08

    Wearable energy sources are in urgent demand due to the rapid development of wearable electronics. Besides flexibility and ultrathin thickness, emerging 2D materials present certain extraordinary properties that surpass the properties of conventional materials, which make them advantageous for high-performance wearable energy sources. Here, we provide a comprehensive review of recent advances in 2D material based wearable energy sources including wearable batteries, supercapacitors, and different types of energy harvesters. The crucial roles of 2D materials in the wearable energy sources are highlighted. Based on the current progress, the existing challenges and future prospects are outlined and discussed.

  2. New ternary tantalum borides containing boron dumbbells: Experimental and theoretical studies of Ta2OsB2 and TaRuB

    Science.gov (United States)

    Mbarki, Mohammed; Touzani, Rachid St.; Rehorn, Christian W. G.; Gladisch, Fabian C.; Fokwa, Boniface P. T.

    2016-10-01

    The new ternary transition metal-rich borides Ta2OsB2 and TaRuB have been successfully synthesized by arc-melting the elements in a water-cooled crucible under an argon atmosphere. The crystal structures of both compounds were solved by single-crystal X-ray diffraction and their metal compositions were confirmed by EDX analysis. It was found that Ta2OsB2 and TaRuB crystallize in the tetragonal Nb2OsB2 (space group P4/mnc, no. 128) and the orthorhombic NbRuB (space group Pmma, no. 51) structure types with lattice parameters a=5.878(2) Å, c=6.857(2) Å and a=10.806(2) Å, b=3.196(1) Å, c=6.312(2) Å, respectively. Furthermore, crystallographic, electronic and bonding characteristics have been studied by density functional theory (DFT). Electronic structure relaxation has confirmed the crystallographic parameters while COHP bonding analysis indicates that B2-dummbells are the strongest bonds in both compounds. Moreover, the formation of osmium dumbbells in Ta2OsB2 through a Peierls distortion along the c-axis, is found to be the origin of superstructure formation. Magnetic susceptibility measurements reveal that the two phases are Pauli paramagnets, thus confirming the theoretical DOS prediction of metallic character. Also hints of superconductivity are found in the two phases, however lack of single phase samples has prevented confirmation. Furthermore, the thermodynamic stability of the two modifications of AMB (A=Nb, Ta; M =Ru, Os) are studied using DFT, as new possible phases containing either B4- or B2-units are predicted, the former being the most thermodynamically stable modification.

  3. Electronic Spectroscopy of B Atoms and B2 Molecules Isolated in Para-H2, Normal-D2, Ne, Ar, Kr, and Xe Matrices

    National Research Council Canada - National Science Library

    Tam, Simon

    2000-01-01

    ...), Ne, Ar, Kr, and Xe matrices, and of B2 molecules in Ne, Ar, Kr, and Xe matrices. The 2s(sup 2)3s((sup 2)S) left arrow 2s(sup 2)2p((sup 2)P) B atom Rydberg absorption suffers large gas-to-matrix blue shifts, increasing...

  4. Argon discharge characteristics in cold cathode penning ion source. Vol. 2

    Energy Technology Data Exchange (ETDEWEB)

    Abd El-Baki, M M; Abd El-Rahman, M M; Basal, N I [Ion Sources and Accelerators Department, Nuclear Research Center, Atomic energy Authority, Cairo, (Egypt)

    1996-03-01

    This study includes the production of argon discharge inside cold cathode penning ion source with axial d.c. extraction. The arc characteristics are investigated under the influence of the discharge parameters such as the pressure, axial magnetic field. At zero magnetic field and pressure 4.2 x 10{sup -4} torr, the arc voltage which is needed for arc initiation is relatively large V{sub arc} = 430 V, and I{sub arc} = 0.3 A. The application of the magnetic field helps the appearance of argon arc at lower voltage, e.g. at I{sub B} = 0.8 A, the arc voltage V{sub arc} = 320 V, and I{sub arc} = 0.3 A. It is found that the arc current increase with the increase of pressure, i.e. the increase of gas flow inside the source, while the arc voltage decreases. 7 fig.

  5. Supply with the vitamins B1, B2 and B6 in carcinomas before and after radiotherapy

    International Nuclear Information System (INIS)

    Grimm, U.; Wulff, K.; Schmidt, W.

    1983-01-01

    In 108 breast cancer, 63 cervix carcinoma, 35 corpus carcinoma and 15 ovarial cancer patients the erythrocyte transketolase, gluthathione reductase and aspartate aminotransferase activity were determined as parameters for the supply with vitamin B 1 , B 2 and B 6 before and after radiotherapy. The effects of thiamine pyrophosphate determined in cancer patients were normal but the effects of flavin adenine dinucleotide and pyridoxal-5-phosphate were significantly increased compared to the controls. These results revealed radiation-induced disorders in the B 2 metabolism and tumor-induced disorders in the B 6 metabolism. Both disorders can be avoided by treatment with vitamin B complex. (author)

  6. Do self-service technologies affect interfirm relationships? A B2B perspective

    Directory of Open Access Journals (Sweden)

    Raechel Johns

    2014-11-01

    Full Text Available While considerable literature examines business-to business (B2B relationships, the impact of technology on these relationships has lacked attention. IT has impacted the way businesses operate in a B2B context as well as influencing services by altering the way services are delivered. To understand the way in which Internet technology has impacted these B2B services, it is essential to examine its impact not only on business processes but on business relationships too. One technology, enabled by modern Internet technologies, which is changing the nature of business relationships is the increased use of self-service technologies (SSTs or technology-enabled services, however, there is a shortage of research in the area in a B2B context. The discussion in this paper provides an overview of the impact of IT on business relationships, using Relationship Marketing theory to provide a theoretical framework. A qualitative study in the Australian banking industry provides findings relating to the theory. The findings of this study provide evidence that while traditional Relationship Marketing theory is still applicable for some business customers, new theory is required for business customers who do not seek relationships. With both practical and theoretical implications, the research detailed in this paper makes a useful contribution to the literature and indicates the necessity for further research to be developed which explores business customers who prefer to remain transaction-oriented, rather than develop interpersonal relationships.

  7. New ternary tantalum borides containing boron dumbbells: Experimental and theoretical studies of Ta{sub 2}OsB{sub 2} and TaRuB

    Energy Technology Data Exchange (ETDEWEB)

    Mbarki, Mohammed; Touzani, Rachid St.; Rehorn, Christian W.G.; Gladisch, Fabian C. [Institute of Inorganic Chemistry, RWTH Aachen University, D-52056 Aachen (Germany); Fokwa, Boniface P.T., E-mail: bfokwa@ucr.edu [Institute of Inorganic Chemistry, RWTH Aachen University, D-52056 Aachen (Germany); Department of Chemistry, University of California Riverside (UCR), Riverside, CA 92521 (United States)

    2016-10-15

    The new ternary transition metal-rich borides Ta{sub 2}OsB{sub 2} and TaRuB have been successfully synthesized by arc-melting the elements in a water-cooled crucible under an argon atmosphere. The crystal structures of both compounds were solved by single-crystal X-ray diffraction and their metal compositions were confirmed by EDX analysis. It was found that Ta{sub 2}OsB{sub 2} and TaRuB crystallize in the tetragonal Nb{sub 2}OsB{sub 2} (space group P4/mnc, no. 128) and the orthorhombic NbRuB (space group Pmma, no. 51) structure types with lattice parameters a=5.878(2) Å, c=6.857(2) Å and a=10.806(2) Å, b=3.196(1) Å, c=6.312(2) Å, respectively. Furthermore, crystallographic, electronic and bonding characteristics have been studied by density functional theory (DFT). Electronic structure relaxation has confirmed the crystallographic parameters while COHP bonding analysis indicates that B{sub 2}-dummbells are the strongest bonds in both compounds. Moreover, the formation of osmium dumbbells in Ta{sub 2}OsB{sub 2} through a Peierls distortion along the c-axis, is found to be the origin of superstructure formation. Magnetic susceptibility measurements reveal that the two phases are Pauli paramagnets, thus confirming the theoretical DOS prediction of metallic character. Also hints of superconductivity are found in the two phases, however lack of single phase samples has prevented confirmation. Furthermore, the thermodynamic stability of the two modifications of AMB (A=Nb, Ta; M =Ru, Os) are studied using DFT, as new possible phases containing either B{sub 4}- or B{sub 2}-units are predicted, the former being the most thermodynamically stable modification. - Graphical abstract: The two new ternary tantalum borides, Ta{sub 2}OsB{sub 2} and TaRuB, have been discovered. Their crystal structures contain boron dumbbells, which are the strongest bonds. Peirls distortion is found responsible for Os{sub 2}-dumbbells formation in Ta{sub 2}OsB{sub 2}. Ta{sub 2}OsB{sub 2} and

  8. Defect structure of ultrafine MgB2 nanoparticles

    International Nuclear Information System (INIS)

    Bateni, Ali; Somer, Mehmet; Repp, Sergej; Erdem, Emre; Thomann, Ralf; Acar, Selçuk

    2014-01-01

    Defect structure of MgB 2 bulk and ultrafine particles, synthesized by solid state reaction route, have been investigated mainly by the aid of X-band electron paramagnetic resonance spectrometer. Two different amorphous Boron (B) precursors were used for the synthesis of MgB 2 , namely, boron 95 (purity 95%–97%, <1.5 μm) and nanoboron (purity >98.5%, <250 nm), which revealed bulk and nanosized MgB 2 , respectively. Scanning and transmission electron microscopy analysis demonstrate uniform and ultrafine morphology for nanosized MgB 2 in comparison with bulk MgB 2 . Powder X-ray diffraction data show that the concentration of the by-product MgO is significantly reduced when nanoboron is employed as precursor. It is observed that a significant average particle size reduction for MgB 2 can be achieved only by using B particles of micron or nano size. The origin and the role of defect centers were also investigated and the results proved that at nanoscale MgB 2 material contains Mg vacancies. Such vacancies influence the connectivity and the conductivity properties which are crucial for the superconductivity applications

  9. Morita-Baylis-Hillman Route to Dimethyl 2,3-Dihydrobenzo[b]oxepine-2,4- dicarboxylates and Methyl 2-(2-Carbomethoxybenzo[b]furan-3-yl)propanoates from Salicylaldehydes

    International Nuclear Information System (INIS)

    Ahn, Sang Hyun; Jang, Seung Soon; Kim, Young Keun; Lee, Kee Jung

    2012-01-01

    A new synthetic method for dimethyl 2,3-dihydrobenzo[b]oxepine-2,4-dicarboxylates and methyl 2-(2- carbomethoxybenzo[b]furan-3-yl)propanoates by an intramolecular conjugate displacement reaction or an S N 2 reaction of acetates of Morita-Baylis-Hillman adducts of methyl (2-formylphenoxy)acetates has been described

  10. Using service design methods for B2b service brand concept development: Case company

    OpenAIRE

    Molina Escalante, Hugo

    2014-01-01

    A short time before this study was initiated, a small B2b service company had just began op-erating its business without a brand of it’s own. The company owners were looking to design an innovative brand for their business. The purpose of this thesis was to develop the brand for this service Company in the B2b context, using practical service design and Strategic design research methods. This thesis report represents a framework for developing a B2b service brand using research methods c...

  11. Designing the marketing-sales interface in B2B firms

    NARCIS (Netherlands)

    Biemans, W.G.; Makovec Brencic, M.

    2007-01-01

    Purpose - This paper explores the marketing-sales interface in Dutch and Slovenian B2B firms. Design/methodology/approach - The study included 11 Dutch firms and ten Slovenian firms, with both samples as closely matched as possible. The firms were all manufacturers of physical products that operate

  12. EBI2 overexpression in mice leads to B1 B-cell expansion and chronic lymphocytic leukemia-like B-cell malignancies.

    Science.gov (United States)

    Niss Arfelt, Kristine; Barington, Line; Benned-Jensen, Tau; Kubale, Valentina; Kovalchuk, Alexander L; Daugvilaite, Viktorija; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup; Egerod, Kristoffer L; Bassi, Maria R; Spiess, Katja; Schwartz, Thue W; Wang, Hongsheng; Morse, Herbert C; Holst, Peter J; Rosenkilde, Mette M

    2017-02-16

    Human and mouse chronic lymphocytic leukemia (CLL) develops from CD5 + B cells that in mice and macaques are known to define the distinct B1a B-cell lineage. B1a cells are characterized by lack of germinal center (GC) development, and the B1a cell population is increased in mice with reduced GC formation. As a major mediator of follicular B-cell migration, the G protein-coupled receptor Epstein-Barr virus-induced gene 2 ( EBI2 or GPR183 ) directs B-cell migration in the lymphoid follicles in response to its endogenous ligands, oxysterols. Thus, upregulation of EBI2 drives the B cells toward the extrafollicular area, whereas downregulation is essential for GC formation. We therefore speculated whether increased expression of EBI2 would lead to an expanded B1 cell subset and, ultimately, progression to CLL. Here, we demonstrate that B-cell-targeted expression of human EBI2 (hEBI2) in mice reduces GC-dependent immune responses, reduces total immunoglobulin M (IgM) and IgG levels, and leads to increased proliferation and upregulation of cellular oncogenes. Furthermore, hEBI2 overexpression leads to an abnormally expanded CD5 + B1a B-cell subset (present as early as 4 days after birth), late-onset lymphoid cancer development, and premature death. These findings are highly similar to those observed in CLL patients and identify EBI2 as a promoter of B-cell malignancies.

  13. Morita-Baylis-Hillman Route to Dimethyl 2,3-Dihydrobenzo[b]oxepine-2,4- dicarboxylates and Methyl 2-(2-Carbomethoxybenzo[b]furan-3-yl)propanoates from Salicylaldehydes

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sang Hyun; Jang, Seung Soon; Kim, Young Keun; Lee, Kee Jung [Hanyang University, Seoul (Korea, Republic of)

    2012-01-15

    A new synthetic method for dimethyl 2,3-dihydrobenzo[b]oxepine-2,4-dicarboxylates and methyl 2-(2- carbomethoxybenzo[b]furan-3-yl)propanoates by an intramolecular conjugate displacement reaction or an S{sub N}2 reaction of acetates of Morita-Baylis-Hillman adducts of methyl (2-formylphenoxy)acetates has been described.

  14. Preparation, characterization, and thermal stability of B2O3-ZrO2

    Directory of Open Access Journals (Sweden)

    Theresia Debora Simbolon

    2017-04-01

    Full Text Available Synthesis of the borate-based compound with ZrOCl2 to form B2O3-ZrO2 has been conducted. The compound was characterized by FT-IR spectrophotometer, X-ray diffraction, acidity and thermal stability test. The results showed that the FT-IR main vibration spectrum of B2O3-ZrO2 compound has appeared at wave number 401.2 cm-1 for Zr-O bonding vibration, 617.2 cm-1 for B-O-B bonding vibration and 910.4 cm-1 for B-O bonding vibration. The XRD diffraction pattern shows B2O3-ZrO2 compound has an amorphous structure. The FT-IR spectrum after saturated with ammonia and potentiometric titration indicates that the compound of B2O3-ZrO2 has acidic properties with a strong level of acidity. Thermal stability test shows that the B2O3-ZrO2 compounds have high stability on temperature with increasing crystallinity after the compound was heated at 700 °C. Keywords: B2O3-ZrO2, impregnation, thermal stability.

  15. A process-stakeholder analysis of B2B industry standardisation

    NARCIS (Netherlands)

    Rodon, J.; Ramis-Pujol, J.; Christiaanse, E.

    2007-01-01

    Purpose - Interoperability standards are a crucial aspect in the development of B2B e-business. The aim of this paper is to understand how standardisation evolves by analysing the interplay between activities and stakeholders within the process. Unlike most of the IS research that focuses on the

  16. B1 to B2 structural phase transition in LiF under pressure

    Science.gov (United States)

    Jain, Aayushi; Dixit, R. C.

    2018-05-01

    In the last few decades the alkali halides emerged as crystals with useful applications and their high-pressure behaviour is the most intensively studied subject in high-pressure physics/chemistry, material science, and geosciences. Most alkali halides follow the B1 (NaCl-type)→B2 (CsCl-type) phase-transition route under pressure. In the present paper, we have investigated the characteristics of structural phase transition that occurred in Lithium Florid compound under high pressure. The transition pressure of B1-B2 was calculated using an effective interionic interaction potential (EIOP). The changes of the characteristics of crystals like, Gibbs free energy, cohesive energy, volume collapse, and lattice constant are calculated for the B1 and B2 structures. These data were compared with the available experimental and theoretical data.

  17. Structural, optical, and thermal properties of MAX-phase Cr2AlB2

    Science.gov (United States)

    Li, Xiao-Hong; Cui, Hong-Ling; Zhang, Rui-Zhou

    2018-04-01

    First-principles calculations of the structural, optical, and thermal properties of Cr2AlB2 are performed using the pseudopotential plane-wave method within the generalized gradient approximation (GGA). Calculation of the elastic constant and phonon dispersion indicates that Cr2AlB2 is mechanically and thermodynamically stable. Analysis of the band structure and density of states indicates that Cr2AlB2 is metallic. The thermal properties under increasing temperature and pressure are investigated using the quasi-harmonic Debye model. The results show that anharmonic effects on Cr2AlB2 are important at low temperature and high pressure. The calculated equilibrium primitive cell volume is 95.91 Å3 at T = 300 K, P = 0 GPa. The ability of Cr2AlB2 to resist volume changes becomes weaker with increasing temperature and stronger with increasing pressure. Analysis of optical properties of Cr2AlB2 shows that the static dielectric function of Cr2AlB2 is 53.1, and the refractive index n 0 is 7.3. If the incident light has a frequency exceeding 16.09 eV, which is the plasma frequency of Cr2AlB2, Cr2AlB2 changes from metallic to dielectric material.

  18. Trapped field measurements on MgB{sub 2} bulk samples

    Energy Technology Data Exchange (ETDEWEB)

    Koblischka, Michael; Karwoth, Thomas; Zeng, XianLin; Hartmann, Uwe [Institute of Experimental Physics, Saarland University, P. O. Box 151150, D-66041 Saarbruecken (Germany); Berger, Kevin; Douine, Bruno [University of Lorraine, GREEN, 54506 Vandoeuvre-les-Nancy (France)

    2016-07-01

    Trapped field measurements were performed on bulk, polycrystalline MgB{sub 2} samples stemming from different sources with the emphasis to develop applications like superconducting permanent magnets ('supermagnets') and electric motors. We describe the setup for the trapped field measurements and the experimental procedure (field cooling, zero-field cooling, field sweep rates). The trapped field measurements were conducted using a cryocooling system to cool the bulk samples to the desired temperatures, and a low-loss cryostat equipped with a room-temperature bore and a maximum field of ±5 T was employed to provide the external magnetic field. The superconducting coil of this cryostat is operated using a bidirectional power supply. Various sweep rates of the external magnetic field ranging between 1 mT/s and 40 mT/s were used to generate the applied field. The measurements were performed with one sample and two samples stacked together. A maximum trapped field of 7 T was recorded. We discuss the results obtained and the problems arising due to flux jumping, which is often seen for the MgB{sub 2} samples cooled to temperatures below 10 K.

  19. A study of TiB2/TiB gradient coating by laser cladding on titanium alloy

    Science.gov (United States)

    Lin, Yinghua; Lei, Yongping; Li, Xueqiao; Zhi, Xiaohui; Fu, Hanguang

    2016-07-01

    TiB2/TiB gradient coating has been fabricated by a laser cladding technique on the surface of a Ti-6Al-4V substrate using TiB2 powder as the cladding material. The microstructure and mechanical properties of the gradient coating were analyzed by SEM, EPMA, XRD, TEM and an instrument to measure hardness. With the increasing distance from the coating surface, the content of TiB2 particles gradually decreased, but the content of TiB short fibers gradually increased. Meanwhile, the micro-hardness and the elastic modulus of the TiB2/TiB coating showed a gradient decreasing trend, but the fracture toughness showed a gradient increasing trend. The fracture toughness of the TiB2/TiB coating between the center and the bottom was improved, primarily due to the debonding of TiB2 particles and the high fracture of TiB short fibers, and the fracture position of TiB short fiber can be moved to an adjacent position. However, the debonding of TiB2 particles was difficult to achieve at the surface of the TiB2/TiB coating.

  20. CH2 molecular beam source

    International Nuclear Information System (INIS)

    Porter, R.A.R.; Grosser, A.E.

    1980-01-01

    A molecular beam source of CH 2 is described. Coaxial beams of methylene halide and alkali metal react and the mixture is formed into a molecular beam. Passage through a mechanical velocity selector rotating at a suitably high speed purifies the beam, separating light, fast CH 2 from heavier, slower contaminating species

  1. Efficient production of lignocellulolytic enzymes xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by the mutant strain Aspergillus awamori 2B.361 U2/1

    Directory of Open Access Journals (Sweden)

    Leda Maria Fortes Gottschalk

    2013-01-01

    Full Text Available The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 ºC and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L, which was not detected in the T. reesei culture.

  2. Vaccination of dogs with canine parvovirus type 2b (CPV-2b) induces neutralising antibody responses to CPV-2a and CPV-2c.

    Science.gov (United States)

    Wilson, Stephen; Illambas, Joanna; Siedek, Elisabeth; Stirling, Catrina; Thomas, Anne; Plevová, Edita; Sture, Gordon; Salt, Jeremy

    2014-09-22

    Since the identification of canine parvovirus type 2, three variants have subsequently been observed differing from the historical CPV-2 and each other by 1-2 amino acids only. As a result there has been considerable research into differential diagnostics, with some researchers indicating there is a need for new vaccines containing different strains of CPV-2. In this study we investigated whether vaccination with a CPV-2b containing vaccine would induce cross-reactive antibody responses to the other CPV-2 variants. Two studies where dogs were vaccinated with a multivalent vaccine, subsequently challenged with CPV-2b and sera samples analysed are presented. Six week old pups with defined serological status were vaccinated twice, three weeks apart and challenged either 5 weeks (MDA override study) or one year after vaccination (duration of immunity study). Sera samples were collected before each vaccination and at periods throughout each study. In each study the antibody profiles were very similar; serological responses against CPV-2a, CPV-2b and CPV-2c were higher than those for CPV-2. Nevertheless, responses against CPV-2 were well above levels considered clinically protective. In each study dogs also showed a rapid increase in antibody titres following vaccination, reached a plateau following second vaccination with a slight decline to challenge after which rapid anamnestic responses were seen. Evaluation of the serological responses suggests vaccination with CPV-2b would cross-protect against CPV-2a and CPV-2c, as well as against CPV-2 which is now extinct in the field. In conclusion we have demonstrated that vaccination of minimum aged dogs with a multivalent vaccine containing the CPV-2b variant strain will induce serological responses which are cross-reactive against all currently circulating field strains, CPV-2a and CPV-2c, and the now extinct field strain CPV-2. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Framing agenda for business model innovation research from the B2B context

    OpenAIRE

    Neupane, Ganesh Prasad; Haugland, Sven A.

    2016-01-01

    This paper reviews the literature on business models in the business-to-business (B2B) context and proposes a research agenda that can be explored by future studies using various management and organizational theories. We outline four research themes and seven research topics for research on business model innovations in the B2B context. Further studies on these topics can make significant contributions to the business model literature.

  4. Development of New B2B Venture Corporate Brand Identity

    DEFF Research Database (Denmark)

    Törmälä, Minna; Gyrd-Jones, Richard I.

    2017-01-01

    of interviews and archival data generated during a three-year period to examine the development of corporate brand over time. This study shows that the development of corporate brand identity and the context of the development of new B2B venture are closely intertwined processes and provides a framework...

  5. Dynamical structure of hadron emission sources

    CERN Document Server

    Zhao Xi; Zhao Shu Song

    2000-01-01

    NA22 experimental data of the triplet seagull effects show that the Doppler effects of hadron emission sources exist exactly in hadron- hadron collisions. Every source possesses the same average energy (CMS) approximately. The collective seagull effects can be also explained by the (aQ)/sup nu /K/sub nu / (aQ) distributions (generalized functions). The dynamical structure of a hadron emission source is described by the (aQ)/sup nu /K/sub nu / (aQ) distributions. The anomalous dimensions of the pionic quantum fields are gamma /sub B/(g/sub R/)=-0.045+or-0.012, which control the singularities of the production amplitude in quantum field theory. The mathematical parameter epsilon =4-D (the dimension D of space time) in the Feynman integrals can be replaced by the anomalous gamma /sub B/(g/sub R/) of the quantum fields for the regularization. (-2 gamma /sub B/(g/sub R/) to or from epsilon /2=1/ln( Lambda /sup 2//m /sup 2/) Lambda to infinity ). (26 refs).

  6. Mineral Carbonation Potential of CO2 from Natural and Industrial-based Alkalinity Sources

    Science.gov (United States)

    Wilcox, J.; Kirchofer, A.

    2014-12-01

    Mineral carbonation is a Carbon Capture and Storage (CSS) technology where gaseous CO2 is reacted with alkaline materials (such as silicate minerals and alkaline industrial wastes) and converted into stable and environmentally benign carbonate minerals (Metz et al., 2005). Here, we present a holistic, transparent life cycle assessment model of aqueous mineral carbonation built using a hybrid process model and economic input-output life cycle assessment approach. We compared the energy efficiency and the net CO2 storage potential of various mineral carbonation processes based on different feedstock material and process schemes on a consistent basis by determining the energy and material balance of each implementation (Kirchofer et al., 2011). In particular, we evaluated the net CO2 storage potential of aqueous mineral carbonation for serpentine, olivine, cement kiln dust, fly ash, and steel slag across a range of reaction conditions and process parameters. A preliminary systematic investigation of the tradeoffs inherent in mineral carbonation processes was conducted and guidelines for the optimization of the life-cycle energy efficiency are provided. The life-cycle assessment of aqueous mineral carbonation suggests that a variety of alkalinity sources and process configurations are capable of net CO2 reductions. The maximum carbonation efficiency, defined as mass percent of CO2 mitigated per CO2 input, was 83% for CKD at ambient temperature and pressure conditions. In order of decreasing efficiency, the maximum carbonation efficiencies for the other alkalinity sources investigated were: olivine, 66%; SS, 64%; FA, 36%; and serpentine, 13%. For natural alkalinity sources, availability is estimated based on U.S. production rates of a) lime (18 Mt/yr) or b) sand and gravel (760 Mt/yr) (USGS, 2011). The low estimate assumes the maximum sequestration efficiency of the alkalinity source obtained in the current work and the high estimate assumes a sequestration efficiency

  7. Kinase activation through dimerization by human SH2-B.

    Science.gov (United States)

    Nishi, Masahiro; Werner, Eric D; Oh, Byung-Chul; Frantz, J Daniel; Dhe-Paganon, Sirano; Hansen, Lone; Lee, Jongsoon; Shoelson, Steven E

    2005-04-01

    The isoforms of SH2-B, APS, and Lnk form a family of signaling proteins that have been described as activators, mediators, or inhibitors of cytokine and growth factor signaling. We now show that the three alternatively spliced isoforms of human SH2-B readily homodimerize in yeast two-hybrid and cellular transfections assays, and this is mediated specifically by a unique domain in its amino terminus. Consistent with previous reports, we further show that the SH2 domains of SH2-B and APS bind JAK2 at Tyr813. These findings suggested a model in which two molecules of SH2-B or APS homodimerize with their SH2 domains bound to two JAK2 molecules, creating heterotetrameric JAK2-(SH2-B)2-JAK2 or JAK2-(APS)2-JAK2 complexes. We further show that APS and SH2-B isoforms heterodimerize. At lower levels of SH2-B or APS expression, dimerization approximates two JAK2 molecules to induce transactivation. At higher relative concentrations of SH2-B or APS, kinase activation is blocked. SH2-B or APS homodimerization and SH2-B/APS heterodimerization thus provide direct mechanisms for activating and inhibiting JAK2 and other kinases from the inside of the cell and for potentiating or attenuating cytokine and growth factor receptor signaling when ligands are present.

  8. Effects of disorder on the microwave properties of MgB2 polycrystalline films

    International Nuclear Information System (INIS)

    Ghigo, G.; Gerbaldo, R.; Gozzelino, L.; Laviano, F.; Mezzetti, E.; Ummarino, G. A.

    2006-01-01

    The role of disorder in superconducting magnesium diboride (MgB 2 ) policrystalline films is investigated in the high frequency range by a coplanar microwave resonator technique. Two sources of disorder are considered, heavy-ion irradiation damage and sample ageing. Microwave measurements are analyzed in the framework of the two-gap model with strong interband scattering contribution. It turns out that disorder enhancement increases the interband scattering rate, resulting in a reduction of the surface resistance at low temperatures, due to a slight increase of the π gap. Moreover, increasing disorder at grain boundaries induces a nonmonotonic residual surface resistance, showing the features of a resistive behavior for the highest disorder level. Finally, the effects of the different kinds of disorder on the intrinsic and on the grain-boundary properties of the MgB 2 films are compared and discussed

  9. Six Years of Monitoring of the Sgr B2 Molecular Cloud with INTEGRAL

    Science.gov (United States)

    Terrier, R.; Bélanger, G.; Ponti, G.; Trap, G.; Goldwurm, A.; Decourchelle, A.

    2009-05-01

    Several molecular clouds around the Galactic Centre (GC) emit strong neutral iron fluorescence line at 6.4 keV, as well as hard X-ray emission up to 100 keV. The origin of this emission has long been a matter of controversy: irradiation by low energy cosmic ray electrons or X-rays emitted by a nearby flaring source in the central region. A recent evidence for time variability in the iron line intensity that has been detected in the Sgr B2 cloud favors the reflexion scenario. We present here the data obtained after 6 years of INTEGRAL monitoring of the GC. In particular, we show a lightcurve of Sgr B2 that reveals a decrease in the hard X-ray flux over the last years and discuss its implications. We finally discuss perspectives with Simbol-X.

  10. Hydroxysteroid sulfotransferase SULT2B1b promotes hepatocellular carcinoma cells proliferation in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Xiaoming Yang

    Full Text Available Hydroxysteroid sulfotransferase 2B1b (SULT2B1b is highly selective for the addition of sulfate groups to 3β-hydroxysteroids. Although previous reports have suggested that SULT2B1b is correlated with cell proliferation of hepatocytes, the relationship between SULT2B1b and the malignant phenotype of hepatocarcinoma cells was not clear. In the present study, we found that SULT2B1 was comparatively higher in the human hepatocarcinoma tumorous tissues than their adjacent tissues. Besides, SULT2B1b overexpression promoted the growth of the mouse hepatocarcinoma cell line Hepa1-6, while Lentivirus-mediated SULT2B1b interference inhibited growth as assessed by the CCK-8 assay. Likewise, inhibition of SULT2B1b expression induced cell-cycle arrest and apoptosis in Hepa1-6 cells by upregulating the expression of FAS, downregulating the expression of cyclinB1, BCL2 and MYC in vitro and in vivo at both the transcript and protein levels. Knock-down of SULT2B1b expression significantly suppressed tumor growth in nude mouse xenografts. Moreover, proliferation rates and SULT2B1b expression were highly correlated in the human hepatocarcinoma cell lines Huh-7, Hep3B, SMMC-7721 and BEL-7402 cells. Knock-down of SULT2B1b inhibited cell growth and cyclinB1 levels in human hepatocarcinoma cells and suppressed xenograft growth in vivo. In conclusion, SULT2B1b expression promotes proliferation of hepatocellular carcinoma cells in vitro and in vivo, which may contribute to the progression of HCC.

  11. Magnetism and superconductivity in ErNi2B2C

    Indian Academy of Sciences (India)

    in modulation vector and harmonic content. Studies of the vortex lattice show the presence of a 45. ◦ reorientation transition and a distorted hexagonal to square transition as a function of applied field. Further distortions of the vortex lattice occur at TN, but no changes are seen at TF. Keywords. (RE)Ni2B2C; ErNi2B2C; vortex ...

  12. Incommensurate magnetic modulations in the magnetic superconductor HoNi2B2C

    International Nuclear Information System (INIS)

    Schneider, M.; Zaharko, O.; Keller, L.; Allenspach, P.; Kreyssig, A.; Canfield, P.C.

    2006-01-01

    Full text: The borocarbide HoNi 2 B 2 C is an unconventional superconductor of particular interest, since long-range magnetism coexists and competes with superconductivity on a common energy range [1]. Our study is based on high quality single crystals of 11 B-substituted HoNi 2 B 2 C. The neutron diffraction investigations are devoted to two issues of specific relevance to HoNi 2 B 2 C. Firstly, the near re-entrant phase between 5K 2 B 2 C is more complicated than proposed so fare [2]. Furthermore we performed a spherical neutron polarimetry experiment to determine the two ICM magnetic structures of HoNi 2 B 2 C and neutron spectroscopy investigations to obtain the microscopic magnetic coupling parameters. All these studies resulted in quite a consistent and complete picture of magnetism in HoNi 2 B 2 C, however, we could not find clear evidence for a strong interaction between superconductivity and magnetism. (author)

  13. The impact of e-marketing orientation on performance in Asian SMEs: a B2B perspective

    Science.gov (United States)

    Chong, Woon Kian; Man, Ka Lok; Kim, Mucheol

    2018-01-01

    Business-to-business (B2B) organisations are increasingly utilising electronic devices in their business operations in order to succeed in increasingly competitive markets. This trend is prevalent in the growing Asian markets, especially in the small and medium-sized enterprises (SMEs) sector. While prior research has focused on this issue in the context of large business-to-customer (B2C) organisations in Asia, there have hardly been any studies that have shed light on the B2B sector in the SME setting. This study aims to critically explore B2B e-marketing critical success factors (B2B-eM-CSFs) for SMEs operating in the Asian B2B marketplace. A key finding is the development of a theoretical framework for SMEs, emerging from the analysis of 406 companies from various industrial sectors. The study shows that interaction with the B2B-eM-CSFs is an important dimension and has a positive and significant impact on e-business efficiency and marketing improvements for Asian SMEs.

  14. Systems Li[sub 2]B[sub 4]O[sub 7] (Na[sub 2]B[sub 4]O[sub 7], K[sub 2]B[sub 4]O[sub 7])-N[sub 2]H[sub 3]H[sub 4]OH-H[sub 2]O at 25 deg C. Sistemy Li[sub 2]B[sub 4]O[sub 7] (Na[sub 2]B[sub 4]O[sub 7], K[sub 2]B[sub 4]O[sub 7])-N[sub 2]H[sub 3]H[sub 4]OH-H[sub 2]O pri 25 grad S

    Energy Technology Data Exchange (ETDEWEB)

    Skvortsov, V G; Sadetdinov, Sh V; Akimov, V M; Mitrasov, Yu N; Petrova, O V; Klopov, Yu N [Chuvashskij Gosudarstvennyj Pedagogicheskij Inst., Cheboksary (Russian Federation) Universitet Druzhby Narodov, Moscow (Russian Federation)

    1994-02-01

    Phase equilibriums in the Li[sub 2]B[sub 4]O[sub 7] (Na[sub 2]B[sub 4]O[sub 7], K[sub 2]B[sub 4]O[sub 7])-N[sub 2]H[sub 3]H[sub 4]OH-H[sub 2]O systems were investigated by methods of isothermal solubility, refractometry and PH-metry at 25 deg C for the first time. Lithium and sodium tetraborates was established to form phases of changed composition mM[sub 2]B[sub 4]O[sub 7][center dot]nN[sub 2]H[sub 3]C[sub 2]H[sub 4]OH[center dot]XH[sub 2]O, where M=Li, Na with hydrazine ethanol. K[sub 2]B[sub 4]O[sub 7][center dot]4H[sub 2]O precipitates in solid phase in the case of potassium salt. Formation of isomorphous mixtures was supported by X-ray diffraction and IR spectroscopy methods.

  15. Design and performance of the 2-ID-B scanning x-ray microscope

    International Nuclear Information System (INIS)

    McNulty, I.

    1998-01-01

    We have constructed a high resolution scanning x-ray microscope at the 2-ID-B beamline at the Advanced Photon Source for 1-4 keV x-ray imaging and microspectroscopy experiments. The microscope uses a Fresnel zone plate to focus coherent x-ray undulator radiation to a 150 nm focal spot on a sample. The spectral flux in the focus is 10 8 ph/s/0.1% BW. X-ray photons transmitted by the sample are detected by an avalanche photodiode as the sample is scanned to form an absorption image. The sample stage has both coarse and fine translation axes for raster scanning and a rotation axis for microtomography experiments. The incident x-ray beam energy can also be scanned via the 2-ID-B monochromator while the sample is kept in focus to record spatially resolved absorption spectra. We have measured the performance of the instrument with various test objects. The microscope hardware, software, and performance are discussed in this paper

  16. Microstructure and mechanical properties investigation of in situ TiB2 and ZrB2 reinforced Al-4Cu composites

    Science.gov (United States)

    Lutfi Anis, Ahmad; Ramli, Rosmamuhammadani; Darham, Widyani; Zakaria, Azlan; Talari, Mahesh Kumar

    2016-02-01

    Conventional Al-Cu alloys exhibit coarse grain structure leading to inferior mechanical properties in as-cast condition. Expensive thermo-mechanical treatments are needed to improve microstructure and corresponding mechanical properties. In situ Al-based composites were developed to improve mechanical properties by dispersion strengthening and grain refinement obtained by the presence of particulates in the melt during solidification. In this work Al-4Cu - 3TiB2 and Al-4Cu-3ZrB2 in situ composites were prepared by liquid casting method. XRD, electron microscopy and mechanical tests were performed on suitably sectioned and metallographically prepared surfaces to investigate the phase distribution, hardness and tensile properties. It was found that the reinforcement particles were segregated along the grain boundaries of Al dendrites. Tensile fracture morphology for both Al-4Cu - 3TiB2 and Al-4Cu-3ZrB2 were analyzed and compared to determine the fracture propagation mechanism in the composites. Al-4Cu-3ZrB2 in situ composites displayed higher strength and hardness compared to Al-4Cu-3TiB2 which could be ascribed to the stronger interfacial bonding between the Al dendrites and ZrB2 particulates as evidenced from fractographs.

  17. Effects of HfB2 and HfN Additions on the Microstructures and Mechanical Properties of TiB2-Based Ceramic Tool Materials

    Science.gov (United States)

    An, Jing; Song, Jinpeng; Liang, Guoxing; Gao, Jiaojiao; Xie, Juncai; Cao, Lei; Wang, Shiying; Lv, Ming

    2017-01-01

    The effects of HfB2 and HfN additions on the microstructures and mechanical properties of TiB2-based ceramic tool materials were investigated. The results showed that the HfB2 additive not only can inhibit the TiB2 grain growth but can also change the morphology of some TiB2 grains from bigger polygons to smaller polygons or longer ovals that are advantageous for forming a relatively fine microstructure, and that the HfN additive had a tendency toward agglomeration. The improvement of flexural strength and Vickers hardness of the TiB2-HfB2 ceramics was due to the relatively fine microstructure; the decrease of fracture toughness was ascribed to the formation of a weaker grain boundary strength due to the brittle rim phase and the poor wettability between HfB2 and Ni. The decrease of the flexural strength and Vickers hardness of the TiB2-HfN ceramics was due to the increase of defects such as TiB2 coarse grains and HfN agglomeration; the enhancement of fracture toughness was mainly attributed to the decrease of the pore number and the increase of the rim phase and TiB2 coarse grains. The toughening mechanisms of TiB2-HfB2 ceramics mainly included crack bridging and transgranular fracture, while the toughening mechanisms of TiB2-HfN ceramics mainly included crack deflection, crack bridging, transgranular fracture, and the core-rim structure. PMID:28772821

  18. Effects of HfB2 and HfN Additions on the Microstructures and Mechanical Properties of TiB2-Based Ceramic Tool Materials

    Directory of Open Access Journals (Sweden)

    Jing An

    2017-04-01

    Full Text Available The effects of HfB2 and HfN additions on the microstructures and mechanical properties of TiB2-based ceramic tool materials were investigated. The results showed that the HfB2 additive not only can inhibit the TiB2 grain growth but can also change the morphology of some TiB2 grains from bigger polygons to smaller polygons or longer ovals that are advantageous for forming a relatively fine microstructure, and that the HfN additive had a tendency toward agglomeration. The improvement of flexural strength and Vickers hardness of the TiB2-HfB2 ceramics was due to the relatively fine microstructure; the decrease of fracture toughness was ascribed to the formation of a weaker grain boundary strength due to the brittle rim phase and the poor wettability between HfB2 and Ni. The decrease of the flexural strength and Vickers hardness of the TiB2-HfN ceramics was due to the increase of defects such as TiB2 coarse grains and HfN agglomeration; the enhancement of fracture toughness was mainly attributed to the decrease of the pore number and the increase of the rim phase and TiB2 coarse grains. The toughening mechanisms of TiB2-HfB2 ceramics mainly included crack bridging and transgranular fracture, while the toughening mechanisms of TiB2-HfN ceramics mainly included crack deflection, crack bridging, transgranular fracture, and the core-rim structure.

  19. Vitamin B-12 concentrations in breast milk are low and are not associated with reported household hunger, recent animal source food or vitamin B-12 intake among women in rural Kenya

    Science.gov (United States)

    Background: Breastmilk vitamin B-12 concentration may be inadequate in mothers living in regions where animal source food consumption is low or infrequent. Vitamin B-12 deficiency causes megaloglastic anemia and impairs growth and development in children. Objective: To measure vitamin B-12 in breast...

  20. Structure and bonding of transition metal-boryl compounds. Theoretical study of [(PH3)2(CO)ClOs-BR2] and [(PH3)2(CO)2ClOs-BR2] (BR2 = BH2, BF2, B(OH)2, B(OCH=CHO), Bcat).

    Science.gov (United States)

    Giju, K T; Bickelhaupt, F M; Frenking, G

    2000-10-16

    Quantum chemical DFT calculations using the B3LYP functionals have been carried out for the electronically unsaturated 16 VE five-coordinate osmium boryl-complexes [(PH3)2(CO)ClOs-BR2] and the 18 VE six-coordinate complexes [(PH3)2(CO)2ClOs-BR2] with BR2 = BH2, BF2, B(OH)2, B(OHC=CHO), and Bcat (cat = catecholate O2C6H4). The bonding situation of the Os-BR2 bond was analyzed with the help of the NBO partitioning scheme. The Os-B bond dissociation energies of the 16 VE complexes are very high, and they do not change very much for the different boryl ligands. The 18 VE complexes have only slightly lower bond energies than the 16 VE species. The Os-B bond in both classes of compounds is provided by a covalent sigma-bond which is polarized toward osmium and by strong charge attraction. Os-->B pi-donation is not important for the Os-B binding interactions, except for the Os-BH2 complexes. The stability of the boryl complexes [Os]-BR2 comes mainly from BB pi-donation. The intraligand charge distribution of the BR2 group changes little when the Os-B bond is formed, except for BH2. The CO ligand in [(PH3)2(CO)2ClOs-BR2] which is trans to BR2 has a relatively weak bond to the osmium atom.

  1. MgB{sub 2} superconductors for applications

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, B A; Majoros, M; Eisterer, M; Toenies, S; Weber, H W; Fukutomi, M; Komori, K; Togano, K

    2003-05-01

    The paper presents up to date results on MgB{sub 2} filamentary conductors and coated conductors from the point of view of their possible applications. Basic physical parameters of MgB{sub 2} compound relevant to conductor design are introduced. The correlation between the slope of the irreversibility line, critical temperature and critical current density is discussed with respect to the conductor performance and applicability. The possible origin of the observed anomalous decrease of ac susceptibility at 50 K in copper clad in situ powder-in-tube MgB{sub 2} wires is presented. Some numerical results on critical currents, thermal stability and ac losses of the MgB{sub 2} multifilamentary and coated conductors with magnetic cladding of their filaments are given.

  2. Trypanosoma brucei Co-opts NK Cells to Kill Splenic B2 B Cells.

    Directory of Open Access Journals (Sweden)

    Deborah Frenkel

    2016-07-01

    Full Text Available After infection with T. brucei AnTat 1.1, C57BL/6 mice lost splenic B2 B cells and lymphoid follicles, developed poor parasite-specific antibody responses, lost weight, became anemic and died with fulminating parasitemia within 35 days. In contrast, infected C57BL/6 mice lacking the cytotoxic granule pore-forming protein perforin (Prf1-/- retained splenic B2 B cells and lymphoid follicles, developed high-titer antibody responses against many trypanosome polypeptides, rapidly suppressed parasitemia and did not develop anemia or lose weight for at least 60 days. Several lines of evidence show that T. brucei infection-induced splenic B cell depletion results from natural killer (NK cell-mediated cytotoxicity: i B2 B cells were depleted from the spleens of infected intact, T cell deficient (TCR-/- and FcγRIIIa deficient (CD16-/- C57BL/6 mice excluding a requirement for T cells, NKT cell, or antibody-dependent cell-mediated cytotoxicity; ii administration of NK1.1 specific IgG2a (mAb PK136 but not irrelevant IgG2a (myeloma M9144 prevented infection-induced B cell depletion consistent with a requirement for NK cells; iii splenic NK cells but not T cells or NKT cells degranulated in infected C57BL/6 mice co-incident with B cell depletion evidenced by increased surface expression of CD107a; iv purified NK cells from naïve C57BL/6 mice killed purified splenic B cells from T. brucei infected but not uninfected mice in vitro indicating acquisition of an NK cell activating phenotype by the post-infection B cells; v adoptively transferred C57BL/6 NK cells prevented infection-induced B cell population growth in infected Prf1-/- mice consistent with in vivo B cell killing; vi degranulated NK cells in infected mice had altered gene and differentiation antigen expression and lost cytotoxic activity consistent with functional exhaustion, but increased in number as infection progressed indicating continued generation. We conclude that NK cells in T. brucei

  3. Source apportionment of PM2.5 in North India using source-oriented air quality models

    International Nuclear Information System (INIS)

    Guo, Hao; Kota, Sri Harsha; Sahu, Shovan Kumar; Hu, Jianlin; Ying, Qi; Gao, Aifang; Zhang, Hongliang

    2017-01-01

    In recent years, severe pollution events were observed frequently in India especially at its capital, New Delhi. However, limited studies have been conducted to understand the sources to high pollutant concentrations for designing effective control strategies. In this work, source-oriented versions of the Community Multi-scale Air Quality (CMAQ) model with Emissions Database for Global Atmospheric Research (EDGAR) were applied to quantify the contributions of eight source types (energy, industry, residential, on-road, off-road, agriculture, open burning and dust) to fine particulate matter (PM 2.5 ) and its components including primary PM (PPM) and secondary inorganic aerosol (SIA) i.e. sulfate, nitrate and ammonium ions, in Delhi and three surrounding cities, Chandigarh, Lucknow and Jaipur in 2015. PPM mass is dominated by industry and residential activities (>60%). Energy (∼39%) and industry (∼45%) sectors contribute significantly to PPM at south of Delhi, which reach a maximum of 200 μg/m 3 during winter. Unlike PPM, SIA concentrations from different sources are more heterogeneous. High SIA concentrations (∼25 μg/m 3 ) at south Delhi and central Uttar Pradesh were mainly attributed to energy, industry and residential sectors. Agriculture is more important for SIA than PPM and contributions of on-road and open burning to SIA are also higher than to PPM. Residential sector contributes highest to total PM 2.5 (∼80 μg/m 3 ), followed by industry (∼70 μg/m 3 ) in North India. Energy and agriculture contribute ∼25 μg/m 3 and ∼16 μg/m 3 to total PM 2.5 , while SOA contributes <5 μg/m 3 . In Delhi, industry and residential activities contribute to 80% of total PM 2.5 . - Highlights: • Sources of PM 2.5 in North India were quantified by source-oriented CMAQ. • Industrial/residential activities are the dominating sources (60–70%) for PPM. • Energy/agriculture are the most important sources (30–40%) for SIA. • Strong seasonal

  4. Haplotypes frequencies of CYP2B6 in Malaysia

    Directory of Open Access Journals (Sweden)

    N Musa

    2012-01-01

    Full Text Available Background: Drugs with complex pharmacology are used in the management of drug use disorder (DUD and HIV/AIDS in Malaysia and in parts of South-East Asia. Their multiethnic populations suggest complexity due to the genetic polymorphism, such as CYP2B6 that metabolizes methadone and anti-retroviral. Aims: Our aim was to explore the genetic polymorphism of CYP2B6 among Malays, Chinese, Indians, and opiate-dependent individuals in Malaysia. Settings and Design: The study utilized DNA from our previous studies on CYPs and new recruitments from opiate-dependent individuals. Materials and Methods: For the new recruitment, after obtaining consent and baseline demography, 5 ml blood was obtained from patients attending methadone maintenance therapy (MMT Clinics. Genomic DNA was extracted using standard methods. 10 nucleotide changes associated with CYP2B6FNx0110, CYP2B6FNx012, CYP2B6FNx0117, CYP2B6FNx0111, CYP2B6FNx018, CYP2B6FNx0114, CYP2B6FNx019, CYP2B6FNx014, CYP2B6FNx016, CYP2B6FNx0127, and CYP2B6FNx0120 were determined using multiplex nested allele-specific PCR. Statistical Analysis: Descriptive statistics were used to summarize demographic data. Differences in allele frequencies between populations were tested using Chi-squared test and were corrected using the Bonferroni test. Results: CYP2B6 polymorphism in Malaysia is variable with trends that suggest an ethnic difference. Reduced activity CYP2B6FNx016 occurred in 13% to 26% among Malays, Chinese, Indians and opiate-dependent individuals. Another ′reduced activity′, CYP2B6FNx012 allele, was found at much lower percentages in the groups. Conclusions: The relative commonness of reduced-activity CYP2B6 alleles in our study called for attention in terms of dosage requirements for MMT and ARV in Malaysia. It also implored follow-up association studies to determine its relevance and consequences in personalized medicine for drug use disorder and HIV/AIDS.

  5. Pantechnik new superconducting ion source: PantechniK Indian Superconducting Ion Source

    International Nuclear Information System (INIS)

    Gaubert, G.; Bieth, C.; Bougy, W.; Brionne, N.; Donzel, X.; Leroy, R.; Sineau, A.; Vallerand, C.; Villari, A. C. C.; Thuillier, T.

    2012-01-01

    The new ECR ion source PantechniK Indian Superconducting Ion Source (PKISIS) was recently commissioned at Pantechnik. Three superconducting coils generate the axial magnetic field configuration, while the radial magnetic field is done with the multi-layer permanent magnets. Special care was devoted to the design of the hexapolar structure, allowing a maximum magnetic field of 1.32 T at the wall of the 82 mm diameter plasma chamber. The three superconducting coils using low temperature superconducting wires are cooled by a single double stage cryo-cooler (4.2 K). Cryogen-free technology is used, providing reliability and easy maintenance at low cost. The maximum installed RF power (18.0 GHz) is of 2 kW. Metallic beams can be produced with an oven (T max = 1400 deg. C) installed with an angle of 5 deg. with respect to the source axis or a sputtering system, mounted on the axis of the source. The beam extraction system is constituted of three electrodes in accel-decel configuration. The new source of Pantechnik is conceived for reaching optimum performances at 18 GHz RF frequencies. PKISIS magnetic fields are 2.1 T axial B inj and 1.32 T radial field in the wall, variable B min with an independent coil and a large and opened extraction region. Moreover, PKISIS integrates modern design concepts, like RF direct injection (2 kW availability), dc-bias moving disk, out-of-axis oven and axial sputtering facility for metal beams. Finally, PKISIS is also conceived in order to operate in a high-voltage platform with minor power consumption.

  6. A Combined Experimental and Theoretical Study on the Formation of Interstellar Propylene Oxide (CH3CHCH2O)—A Chiral Molecule

    Science.gov (United States)

    Bergantini, Alexandre; Abplanalp, Matthew J.; Pokhilko, Pavel; Krylov, Anna I.; Shingledecker, Christopher N.; Herbst, Eric; Kaiser, Ralf I.

    2018-06-01

    This work reveals via a combined experimental, computational, and astrochemical modeling study that racemic propylene oxide (c-C3H6O)—the first chiral molecule detected outside Earth toward the high-mass star-forming region Sagittarius B2(N)—can be synthesized by non-equilibrium reactions initiated by the effects of secondary electrons generated in the track of cosmic rays interacting with ice-coated interstellar grains through excited-state and spin-forbidden reaction pathways operating within low-temperature interstellar ices at 10 K. Our findings confront traditional hypotheses that thermal chemistries followed by processing of interstellar grains dictate the formation of complex organic molecules (COMs) in molecular clouds. Instead, we reveal a hitherto poorly quantified reaction class involving excited-state and spin-forbidden chemistry leading to racemic mixtures of COMs inside interstellar ices prior to their sublimation in star-forming regions. This fundamental production mechanism is of essential consequence in aiding our understanding of the origin and evolution of chiral molecules in the universe.

  7. ONLINE ACQUISITIONS IN B2B MODEL

    Directory of Open Access Journals (Sweden)

    Constantin SASU

    2016-12-01

    Full Text Available Within the present paper, we propose to review some of the main aspects documented by the academic research so far with regard to the online purchasing behaviour in the B2B online environment (more specifically, in the case of the small and medium-sized companies. Preliminary conclusions reveal that, at least in the case studies, the dominant feature is that the geographic delimitation creates a potential obstacle when it comes to applying a general principle governing the small and medium-sized enterprises. Despite this, we consider that some theoretical elements can be acknowledged, elements from which future research can start to develop theories and hypothesis aimed at better explaining the phenomenon. Furthermore, the fact that the studies are rarely involving the same sector, makes it impossible to generalise the process.

  8. Revisiting anomalous B(E2;41+→21+)/B(E2;21+→01+) values in 98Ru and 180Pt

    International Nuclear Information System (INIS)

    Williams, E.; Plettner, C.; McCutchan, E. A.; Levine, H.; Casten, R. F.; Ai, H.; Heinz, A.; Qian, J.; Meyer, D. A.; Werner, V.; Zamfir, N. V.; Cakirli, R. B.; Beausang, C. W.; Guerdal, G.; Pietralla, N.

    2006-01-01

    Recently, a set of nine nonmagic nuclei with anomalous values of the B(E2) ratio B 4/2B(E2;4 1 + →2 1 + )/B(E2;2 1 + →0 1 + ) 1 + →2 1 + ) values for two of these nuclei, 98 Ru and 180 Pt, were re-measured to determine if the current literature values for these nuclei are correct. 98 Ru was studied in a 27 Al( 98 Ru, 98 Ru*) Coulomb excitation experiment in inverse kinematics, while the lifetime of the 4 1 + state in 180 Pt was measured in a 122 Sn( 62 Ni, 4n) 180 Pt recoil distance method (RDM) experiment. For both nuclei, the remeasured B 4/2 values are well above 1, removing the deviations from collective models

  9. An ultrabright and monochromatic electron point source made of a LaB6 nanowire

    Science.gov (United States)

    Zhang, Han; Tang, Jie; Yuan, Jinshi; Yamauchi, Yasushi; Suzuki, Taku T.; Shinya, Norio; Nakajima, Kiyomi; Qin, Lu-Chang

    2016-03-01

    Electron sources in the form of one-dimensional nanotubes and nanowires are an essential tool for investigations in a variety of fields, such as X-ray computed tomography, flexible displays, chemical sensors and electron optics applications. However, field emission instability and the need to work under high-vacuum or high-temperature conditions have imposed stringent requirements that are currently limiting the range of application of electron sources. Here we report the fabrication of a LaB6 nanowire with only a few La atoms bonded on the tip that emits collimated electrons from a single point with high monochromaticity. The nanostructured tip has a low work function of 2.07 eV (lower than that of Cs) while remaining chemically inert, two properties usually regarded as mutually exclusive. Installed in a scanning electron microscope (SEM) field emission gun, our tip shows a current density gain that is about 1,000 times greater than that achievable with W(310) tips, and no emission decay for tens of hours of operation. Using this new SEM, we acquired very low-noise, high-resolution images together with rapid chemical compositional mapping using a tip operated at room temperature and at 10-times higher residual gas pressure than that required for W tips.

  10. Microstructure and Wear Resistance of Laser-Clad (Co, Ni61.2B26.2Si7.8Ta4.8 Coatings

    Directory of Open Access Journals (Sweden)

    Luan Zhang

    2017-10-01

    Full Text Available It has been reported that a quaternary Co61.2B26.2Si7.8Ta4.8 alloy is a good glass former and can be laser-clad to an amorphous composite coating with superior hardness and wear resistance. In this paper, alloys with varying Ni contents to substitute for Co are coated on the surface of #45 carbon steel using a 5-kW CO2 laser source for the purpose of obtaining protective coatings. In contrast to the quaternary case, the clad layers are characterized by a matrix of α-(Fe, Co, Ni solid solution plus CoB, Co3B, and Co3Ta types of precipitates. The cladding layer is divided into four regions: Near-surface dendrites, α-(Fe, Co, Ni solid solution plus dispersed particles in the middle zone, columnar bonding zone, and heat-affected area that consists of martensite. The hardness gradually decreases with increasing Ni content, and the maximum hardness occurs in the middle zone. Both the friction coefficient and wear volume are minimized in the alloy containing 12.2% Ni. Compared with the previous cobalt-based quaternary alloy Co61.2B26.2Si7.8Ta4.8, the addition of the Ni element reduces the glass-forming ability and henceforth the hardness and wear resistance of the clad layers.

  11. Sources of Variability in the Detection of B-Lines, Using Lung Ultrasound.

    Science.gov (United States)

    Pivetta, Emanuele; Baldassa, Federico; Masellis, Serena; Bovaro, Federica; Lupia, Enrico; Maule, Milena M

    2018-06-01

    Lung ultrasound (LUS) is a largely employed diagnostic tool but an operational protocol for implementation has never been proposed. The lack of standardization clearly introduces variability in LUS results. We enrolled adult patients presenting for acute dyspnea with a clinical suspect of etiology related to heart failure. We calculated agreement among four providers in assessing B-lines. We varied probes, depth, evaluation time and scanning areas and we estimated the importance of each factors on B-lines assessment. Overall agreement among raters varied from a kappa of 0.70 to 0.81. The mean number of B-lines was 5.44 (95% confidence interval, CI, 4.1-6.8). This estimate did not suffer variation by the depth used (0.03, 95% CI -0.2-0.2, more B-lines, using 19 cm versus 10 cm). The use of a convex probe and expertise in LUS reduced the number of artifacts by 1.7 (95% CI 1.5-1.9) and 1.1 in comparison with a phased array probe and naive operators. Evaluation time increased estimates by 1.2 (95% CI 1-1.5) and 2.9 (95% CI 2.7-3.9) B-lines for 4" and 7" clips (reference was 2" clips). This study suggests that the probe, the evaluation time and the level of expertise might affect the results of quantitative assessment of B-lines. Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

  12. Isolation and Characterization of Plantaricin Produced by Lactobacillus plantarum Strains (IIA-1A5, IIA-1B1, IIA-2B2

    Directory of Open Access Journals (Sweden)

    I. I. Arief

    2013-08-01

    Full Text Available Bacteriocins produced by Indonesian lactic acid bacteria Lactobacillus plantarum IIA-1A5, IIA-1B1, IIA-2B2 were purified and characterized. Plantaricin W gene had been successfully amplified from all strains. This amplicon showed the expected 200 bp size of plantaricin W gene. This bacteriocins purified from L. plantarum IIA-1A5, IIA-1B1, and IIA-2B2 were named plantaricin IIA-1A5, IIA-1B1, and IIA-2B2. Purification by cation exchange chromatography increased the purity (fold and activity of plantaricins. Purity of plantaricin IIA-1A5 was increased by 3.13 fold with specific activity 13.40 AU/mg. Plantaricin IIA-1B1 had 2.98 fold purity with specific activity 5.12 AU/mg, while purity of plantaricin IIA-2B2 was 1.37 fold with specific activity 7.70 AU/mg. All plantaricins could inhibit the growth of pathogenic bacteria, such as Escherichia coli, Salmonella typhimurium, Bacillus cereus, and Staphylococcus aureus. Plantaricins could be digested by trypsin. Stability of plantaricins at 80 oC for 30 min and at 121 oC for 15 min were affected by type of plantaricin and species of pathogenic bacteria. Generally, plantaricin IIA-1A5 was better as antimicrobial agent than plantaricin IIA-1B1 and plantaricin IIA-2B2.

  13. Observations and modeling of the transiting exoplanets XO-2b, HAT-P-18b, and WASP-80b

    Directory of Open Access Journals (Sweden)

    Kjurkchieva Diana P.

    2017-01-01

    Full Text Available We present photometric observations and transit solutions of the exoplanets XO-2b, HAT-P-18b and WASP 80b. Our solution of the XO-2b transit gave system parameters whose values are close to those of the previous studies. The solutions of the new transits of HAT-P-18b and WASP 80b differ from the previous ones by bigger stellar and planet radii. We obtained new values of the target initial epochs corresponding to slightly different periods. Our investigation reaffirmed that small telescopes can be used successfully for the study of exoplanets orbiting stars brighter than 13 mag.

  14. The Tp0684 (MglB-2 Lipoprotein of Treponema pallidum: A Glucose-Binding Protein with Divergent Topology.

    Directory of Open Access Journals (Sweden)

    Chad A Brautigam

    Full Text Available Treponema pallidum, the bacterium that causes syphilis, is an obligate human parasite. As such, it must acquire energy, in the form of carbon sources, from the host. There is ample evidence that the principal source of energy for this spirochete is D-glucose acquired from its environment, likely via an ABC transporter. Further, there is genetic evidence of a D-glucose chemotaxis system in T. pallidum. Both of these processes may be dependent on a single lipidated chemoreceptor: Tp0684, also called TpMglB-2 for its sequence homology to MglB of Escherichia coli. To broaden our understanding of this potentially vital protein, we determined a 2.05-Å X-ray crystal structure of a soluble form of the recombinant protein. Like its namesake, TpMglB-2 adopts a bilobed fold that is similar to that of the ligand-binding proteins (LBPs of other ABC transporters. However, the protein has an unusual, circularly permuted topology. This feature prompted a series of biophysical studies that examined whether the protein's topological distinctiveness affected its putative chemoreceptor functions. Differential scanning fluorimetry and isothermal titration calorimetry were used to confirm that the protein bound D-glucose in a cleft between its two lobes. Additionally, analytical ultracentrifugation was employed to reveal that D-glucose binding is accompanied by a significant conformational change. TpMglB-2 thus appears to be fully functional in vitro, and given the probable central importance of the protein to T. pallidum's physiology, our results have implications for the viability and pathogenicity of this obligate human pathogen.

  15. The Tp0684 (MglB-2) Lipoprotein of Treponema pallidum: A Glucose-Binding Protein with Divergent Topology.

    Science.gov (United States)

    Brautigam, Chad A; Deka, Ranjit K; Liu, Wei Z; Norgard, Michael V

    2016-01-01

    Treponema pallidum, the bacterium that causes syphilis, is an obligate human parasite. As such, it must acquire energy, in the form of carbon sources, from the host. There is ample evidence that the principal source of energy for this spirochete is D-glucose acquired from its environment, likely via an ABC transporter. Further, there is genetic evidence of a D-glucose chemotaxis system in T. pallidum. Both of these processes may be dependent on a single lipidated chemoreceptor: Tp0684, also called TpMglB-2 for its sequence homology to MglB of Escherichia coli. To broaden our understanding of this potentially vital protein, we determined a 2.05-Å X-ray crystal structure of a soluble form of the recombinant protein. Like its namesake, TpMglB-2 adopts a bilobed fold that is similar to that of the ligand-binding proteins (LBPs) of other ABC transporters. However, the protein has an unusual, circularly permuted topology. This feature prompted a series of biophysical studies that examined whether the protein's topological distinctiveness affected its putative chemoreceptor functions. Differential scanning fluorimetry and isothermal titration calorimetry were used to confirm that the protein bound D-glucose in a cleft between its two lobes. Additionally, analytical ultracentrifugation was employed to reveal that D-glucose binding is accompanied by a significant conformational change. TpMglB-2 thus appears to be fully functional in vitro, and given the probable central importance of the protein to T. pallidum's physiology, our results have implications for the viability and pathogenicity of this obligate human pathogen.

  16. Source apportionment of PM10 and PM2.5 in major urban Greek agglomerations using a hybrid source-receptor modeling process.

    Science.gov (United States)

    Argyropoulos, G; Samara, C; Diapouli, E; Eleftheriadis, K; Papaoikonomou, K; Kungolos, A

    2017-12-01

    A hybrid source-receptor modeling process was assembled, to apportion and infer source locations of PM 10 and PM 2.5 in three heavily-impacted urban areas of Greece, during the warm period of 2011, and the cold period of 2012. The assembled process involved application of an advanced computational procedure, the so-called Robotic Chemical Mass Balance (RCMB) model. Source locations were inferred using two well-established probability functions: (a) the Conditional Probability Function (CPF), to correlate the output of RCMB with local wind directional data, and (b) the Potential Source Contribution Function (PSCF), to correlate the output of RCMB with 72h air-mass back-trajectories, arriving at the receptor sites, during sampling. Regarding CPF, a higher-level conditional probability function was defined as well, from the common locus of CPF sectors derived for neighboring receptor sites. With respect to PSCF, a non-parametric bootstrapping method was applied to discriminate the statistically significant values. RCMB modeling showed that resuspended dust is actually one of the main barriers for attaining the European Union (EU) limit values in Mediterranean urban agglomerations, where the drier climate favors build-up. The shift in the energy mix of Greece (caused by the economic recession) was also evidenced, since biomass burning was found to contribute more significantly to the sampling sites belonging to the coldest climatic zone, particularly during the cold period. The CPF analysis showed that short-range transport of anthropogenic emissions from urban traffic to urban background sites was very likely to have occurred, within all the examined urban agglomerations. The PSCF analysis confirmed that long-range transport of primary and/or secondary aerosols may indeed be possible, even from distances over 1000km away from study areas. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Synthesis and photoluminescence study of rare earth activated phosphor Na2La2B2O7

    International Nuclear Information System (INIS)

    Nagpure, P.A.; Omanwar, S.K.

    2012-01-01

    The photoluminescence properties in UV and N-UV excitable range for the phosphors of Na 2 La 2 B 2 O 7 : RE (RE=Eu, Tb, Ce, Sm, Gd) are investigated. The solution combustion synthesis technique was employed for the synthesis of the phosphors Na 2 La 2 B 2 O 7 : RE. The photoluminescence measurements of the phosphors were carried out on a HITACHI F7000 Fluorescence Spectrophotometer. The PL and PL excitation (PLE) spectra indicate that the main emission wavelength of Na 2 La 2 B 2 O 7 : Eu are 591 and 615 nm, Na 2 La 2 B 2 O 7 : Ce shows dominating emission peak at 387 nm and Na 2 La 2 B 2 O 7 : Tb displays green emission at 493, 544, 593 and 620 nm at 254 nm excitation, while Na 2 La 2 B 2 O 7 : Sm shows the main emission peak wavelengths 566 and 604 nm at 405 nm excitation and Na 2 La 2 B 2 O 7 : Gd shows dominating emission peak at 312 nm at 274 nm excitation. These phosphors may provide a new kind of luminescent materials under ultraviolet and near ultraviolet excitation for various applications. - Highlights: ► We use the combustion technique for synthesis of Na 2 La 2 B 2 O 7 : RE phosphor. ► Phosphor Na 2 La 2 B 2 O 7 : Eu 3+ shows intense red emission under UV excitation. ► Phosphor Na 2 La 2 B 2 O 7 : Tb 3+ shows intense green emission under UV excitation. ► Phosphor Na 2 La 2 B 2 O 7 : Sm 3+ shows orange red emission under near UV excitation. ► Phosphors Na 2 La 2 B 2 O 7 : Ce 3+ and Na 2 La 2 B 2 O 7 : Gd 3+ show near UV and UVB emissions under UV excitation.

  18. Verification of the 2.00 WAPPA-B [Waste Package Performance Assessment-B version] code

    International Nuclear Information System (INIS)

    Tylock, B.; Jansen, G.; Raines, G.E.

    1987-07-01

    The old version of the Waste Package Performance Assessment (WAPPA) code has been modified into a new code version, 2.00 WAPPA-B. The input files and the results for two benchmarks at repository conditions are fully documented in the appendixes of the EA reference report. The 2.00 WAPPA-B version of the code is suitable for computation of barrier failure due to uniform corrosion; however, an improved sub-version, 2.01 WAPPA-B, is recommended for general use due to minor errors found in 2.00 WAPPA-B during its verification procedures. The input files and input echoes have been modified to include behavior of both radionuclides and elements, but the 2.00 WAPPA-B version of the WAPPA code is not recommended for computation of radionuclide releases. The 2.00 WAPPA-B version computes only mass balances and the initial presence of radionuclides that can be released. Future code development in the 3.00 WAPPA-C version will include radionuclide release computations. 19 refs., 10 figs., 1 tab

  19. B1 Cell IgE Impedes Mast Cell-Mediated Enhancement of Parasite Expulsion through B2 IgE Blockade

    OpenAIRE

    Rebecca K. Martin; Sheela R. Damle; Yolander A. Valentine; Matthew P. Zellner; Briana N. James; Joseph C. Lownik; Andrea J. Luker; Elijah H. Davis; Martha M. DeMeules; Laura M. Khandjian; Fred D. Finkelman; Joseph F. Urban, Jr.; Daniel H. Conrad

    2018-01-01

    Helminth infection is known for generating large amounts of poly-specific IgE. Here we demonstrate that innate-like B1 cells are responsible for this IgE production during infection with the nematode parasites Nippostrongylus brasiliensis and Heligmosomoides polygyrus bakeri. In vitro analysis of B1 cell immunoglobulin class switch recombination to IgE demonstrated a requirement for anti-CD40 and IL-4 that was further enhanced when IL-5 was added or when the B1 source was helminth infected mi...

  20. Regulation of normal B-cell differentiation and malignant B-cell survival by OCT2.

    Science.gov (United States)

    Hodson, Daniel J; Shaffer, Arthur L; Xiao, Wenming; Wright, George W; Schmitz, Roland; Phelan, James D; Yang, Yandan; Webster, Daniel E; Rui, Lixin; Kohlhammer, Holger; Nakagawa, Masao; Waldmann, Thomas A; Staudt, Louis M

    2016-04-05

    The requirement for the B-cell transcription factor OCT2 (octamer-binding protein 2, encoded by Pou2f2) in germinal center B cells has proved controversial. Here, we report that germinal center B cells are formed normally after depletion of OCT2 in a conditional knockout mouse, but their proliferation is reduced and in vivo differentiation to antibody-secreting plasma cells is blocked. This finding led us to examine the role of OCT2 in germinal center-derived lymphomas. shRNA knockdown showed that almost all diffuse large B-cell lymphoma (DLBCL) cell lines are addicted to the expression of OCT2 and its coactivator OCA-B. Genome-wide chromatin immunoprecipitation (ChIP) analysis and gene-expression profiling revealed the broad transcriptional program regulated by OCT2 that includes the expression of STAT3, IL-10, ELL2, XBP1, MYC, TERT, and ADA. Importantly, genetic alteration of OCT2 is not a requirement for cellular addiction in DLBCL. However, we detected amplifications of the POU2F2 locus in DLBCL tumor biopsies and a recurrent mutation of threonine 223 in the DNA-binding domain of OCT2. This neomorphic mutation subtly alters the DNA-binding preference of OCT2, leading to the transactivation of noncanonical target genes including HIF1a and FCRL3 Finally, by introducing mutations designed to disrupt the OCT2-OCA-B interface, we reveal a requirement for this protein-protein interface that ultimately might be exploited therapeutically. Our findings, combined with the predominantly B-cell-restricted expression of OCT2 and the absence of a systemic phenotype in our knockout mice, suggest that an OCT2-targeted therapeutic strategy would be efficacious in both major subtypes of DLBCL while avoiding systemic toxicity.

  1. First observation of the $B_{s2}^\\ast(5840)^0 \\to B^{\\ast+} K^-$ and studies of excited $B^0_s$ mesons

    CERN Document Server

    INSPIRE-00258707; Abellan Beteta, C; Adametz, A; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amhis, Y; Anderlini, L; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Baesso, C; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, Th; Bay, A; Beddow, J; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M -O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Corti, G; Couturier, B; Cowan, G A; Craik, D; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dickens, J; Dijkstra, H; Diniz Batista, P; Dogaru, M; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hill, D; Hoballah, M; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Kochebina, O; Komarov, V; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Luo, H; Mac Raighne, A; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Maino, M; Malde, S; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Mazurov, A; McCarthy, J; McGregor, G; McNulty, R; Meissner, M; Merk, M; Merkel, J; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petridis, K; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pie Valls, B; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Rives Molina, V; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Romero Vidal, A; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santinelli, R; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Schaack, P; Schiller, M; Schindler, H; Schleich, S; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; Smith, N A; Smith, E; Smith, M; Sobczak, K; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Swientek, S; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urner, D; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Videau, I; Vieira, D; Vilasis-Cardona, X; Visniakov, J; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Witzeling, W; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, F; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zvyagin, A

    2013-04-09

    Properties of the orbitally excited (L=1) $B_s$ states are studied using 1.0 fb$^{-1}$ of pp collisions at $\\sqrt{s} =7$ TeV collected with the LHCb detector. The first observation of the $B_{s2}^*(5840)^0$ meson decaying to $B^{*+} K^-$ is reported, and the corresponding branching fraction measured relative to the $B^+ K^-$ decay mode. The $B_{s1}(5830)^0 \\to B^{*+} K^-$ decay is observed as well. The width of the $B_{s2}^*(5840)^0$ state is measured for the first time and the masses of the two states are determined with the highest precision to date. The observation of the $B_{s2}^*(5840)^0 \\to B^{*+} K^-$ decay favours the spin-parity assignment $J^P = 2^+$ for the $B_{s2}^*(5840)^0$ meson. In addition, the most precise measurement of the mass difference $m(B^{*+})-m(B^+) = 45.01 \\pm 0.30 (stat) \\pm 0.23 (syst)$ MeV/$c^2$ is obtained.

  2. Characteristics of the brand building on the business (B2B market

    Directory of Open Access Journals (Sweden)

    Gligorijević Mirjana

    2011-01-01

    Full Text Available This paper analyzes the characteristics of the brand building in the business (B2B market. Branding strategy at the business market is complex and difficult to implement because of the many limiting factors. Building a brand in the business market is marked by very specific characteristics of industrial products. The value of B2B brands is built through functional characteristics and performances of the product (functional values and emotional value, which together guarantee the delivery a unique experience of business customers. All marketing mix tools can be considered to be branding instruments. The purpose of this paper is to emphasize the importance of applying a branding strategy on business market.

  3. Evaluation of biobutanol production by Clostridium beijerinckii NRRL B-592 using sweet sorghum as carbon source

    Directory of Open Access Journals (Sweden)

    Luiz Jardel Visioli

    2015-09-01

    Full Text Available In this research it was evaluated the production of biobutanol by Clostridium beijerinckiiNRRL B-592 using sweet sorghum juice as carbon source. Operational variables, like pH and initial inoculum size, as well as supplementation of industrial media with yeast extract and tryptone, were evaluated. The maximum butanol obtained was 2.12g kg-1 using 12.5% of inoculum size, 0.05g 100mL-1 of tryptone and 0.1g 100mL-1 of yeast extract and initial pH of 5.5. The main contribution of this research was to show a systematic procedure for development of a low cost industrial media for biobutanol production from sweet sorghum.

  4. THE ARIZONA RADIO OBSERVATORY CO MAPPING SURVEY OF GALACTIC MOLECULAR CLOUDS. I. THE W51 REGION IN CO AND 13CO J = 2-1 EMISSION

    International Nuclear Information System (INIS)

    Bieging, John H.; Peters, William L.; Kang, Miju

    2010-01-01

    We present 38'' resolution maps of the CO and 13 CO J = 2-1 lines in the molecular clouds toward the H II region complex W51. The maps cover a 1. 0 25 x 1 0 section of the galactic plane and span +30 to +85 km s -1 (LSR) in velocity. The spectral resolution is ∼1.3 km s -1 . The velocity range of the images includes all the gas in the Sagittarius spiral arm. Color figures display the peak line brightness temperature, the velocity-integrated intensity, and 2 km s -1 channel-averaged maps for both isotopologs, and also the CO/ 13 CO J = 2-1 line intensity ratio as a function of velocity. The CO and 13 CO line intensity image cubes are made available in standard FITS format as electronically readable tables. We compare our molecular line maps with the 1.1 mm continuum image from the BOLOCAM Galactic Plane Survey. From our 13 CO image cube, we derive kinematic information for the 99 BGPS sources in the mapped field in the form of Gaussian component fits. The integrated 13 CO line intensity and the 1.1 mm source flux density show only a modest degree of correlation for the 99 sources, likely due to a range of dust and gas physical conditions within the sources. However, the 1.1 mm continuum surface brightness and the integrated 13 CO line intensity for small regions containing single BGPS sources and molecular clouds show very good correlations in many cases. Differences in the shapes of these correlations from one spatial region to another probably result from different physical conditions or structure in the clouds.

  5. Substantial photovoltaic response and morphology tuning in benzo[1,2-b:6,5-b']dithiophene (bBDT) molecular donors.

    Science.gov (United States)

    Harschneck, Tobias; Zhou, Nanjia; Manley, Eric F; Lou, Sylvia J; Yu, Xinge; Butler, Melanie R; Timalsina, Amod; Turrisi, Riccardo; Ratner, Mark A; Chen, Lin X; Chang, Robert P H; Facchetti, Antonio; Marks, Tobin J

    2014-04-21

    The influence of solubilizing substituents on the photovoltaic performance and thin-film blend morphology of new benzo[1,2-b:6,5-b']dithiophene (bBDT) based small molecule donor semiconductors is investigated. Solar cells based on bBDT(TDPP)2-PC71BM with two different types of side chains exhibit high power conversion efficiencies, up to 5.53%.

  6. H2O sources in regions of star formation

    International Nuclear Information System (INIS)

    Lo, K.Y.; Burke, B.F.; Haschick, A.D.

    1975-01-01

    Regions and objects believed to be in early stages of stellar formation have been searched for H 2 O 22-GHz line emission with the Haystack 120-foot (37 m) telescope. The objects include radio condensations, infrared objects in H ii regions, and Herbig-Haro objects. Nine new H 2 O sources were detected in the vicinity of such objects, including the Sharpless H ii regions S152, S235, S255, S269, G45.1+0.1, G45.5+0.1, AFCRL infrared object No. 809--2992, and Herbig-Haro objects 1 and 9. The new H 2 O sources detected in H ii regions are associated, but not coincident, with the the radio condensations. Water vapor line emission was detected in approx.25 percent of the regions searched. The association of H 2 O sources with regions of star formation is taken to be real. The spatial relationship of H 2 O sources to infrared objects, radio condensations, class I OH sources, and molecular clouds are discussed. The suggestion is made that an H 2 O source may be excited by a highly obscured star of extreme youth

  7. Asymmetric 1,8/13,2,x-M2C2B10 14-vertex metallacarboranes by direct electrophilic insertion reactions; the VCD and BHD methods in critical analysis of cage C atom positions.

    Science.gov (United States)

    McAnaw, Amelia; Lopez, Maria Elena; Ellis, David; Rosair, Georgina M; Welch, Alan J

    2014-04-07

    The isolation of six isomeric, low-symmetry, dicobaltacarboranes with bicapped hexagonal antiprismatic cage structures, always in low yield, is described from reactions in which 13-vertex cobaltacarborane anions and sources of cobalt-containing cations were present. The vertex-to-centroid distance (VCD) and boron-H distance (BHD) methods are used to locate the correct C atom positions in the cages, thus allowing the compounds to be identified as 1,13-Cp2-1,13,2,10-closo-Co2C2B10H12 (1), 1,8-Cp2-3-OEt-1,8,2,10-closo-Co2C2B10H11 (2), 1,13-Cp2-1,13,2,9-closo-Co2C2B10H12 (3), 1,8-Cp2-1,8,2,4-closo-Co2C2B10H12 (4), 1,13-Cp2-1,13,2,4-closo-Co2C2B10H12 (5) and 1,8-Cp2-1,8,2,5-closo-Co2C2B10H12 (6). It is shown that a common alternative method of cage C atom identification, using refined (as B) U(eq) values, does not work well, at least in these cases. Having identified the correct isomeric forms of the six dicobaltacarboranes, their syntheses are tentatively rationalised in terms of the direct electrophilic insertion of a {CpCo(+)} fragment into [CpCoC2B10](-) anions and it is demonstrated that compounds 1, 4, 5 and 6 can be successfully prepared by deliberately performing such reactions.

  8. Observation of the $B^0_{s}\\to\\psi{(2\\mathrm{S})}\\eta$ and $B^0_{(s)}\\to\\psi{(2\\mathrm{S})}\\pi^+\\pi^-$ decays

    CERN Document Server

    Aaij, R; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amerio, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bauer, Th; Bay, A; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M -O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Burducea, I; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Couturier, B; Cowan, G A; Craik, D; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Oyanguren Campos, M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dijkstra, H; Dogaru, M; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hill, D; Hoballah, M; Hombach, C; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jaton, P; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Leverington, B; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lohn, S; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Lucchesi, D; Luisier, J; Luo, H; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Maurice, E; Mazurov, A; McCarthy, J; McNulty, R; Mcnab, A; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Morello, M J; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petridis, K; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polikarpov, S; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Rives Molina, V; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodriguez Perez, P; Roiser, S; Romanovsky, V; Romero Vidal, A; Rouvinet, J; Ruf, T; Ruffini, F; Ruiz, H; Ruiz Valls, P; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; Smith, N A; Smith, E; Smith, M; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urner, D; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiechczynski, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, F; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L; Zvyagin, A

    2013-01-01

    First observations of the $B^0_s \\rightarrow \\psi(2S) \\eta$, $B^0 \\rightarrow \\psi(2S) \\pi^+ \\pi^-$ and $B^0_s \\rightarrow \\psi(2S) \\pi^+ \\pi^-$ decays are made using a dataset corresponding to an integrated luminosity of 1.0 $fb^{-1}$ collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of $\\sqrt{s}=7$ TeV. The ratios of the branching fractions of each of the $\\psi(2S)$ modes with respect to the corresponding $J/\\psi$ decays are \\[ \\frac{\\mathcal{B}(B^0_s \\rightarrow \\psi(2S) \\eta) }{\\mathcal{B}(B^0_s \\rightarrow J/\\psi \\eta)} =0.83\\pm0.14\\,(stat)\\pm0.12\\,(syst)\\pm0.02\\,(\\mathcal{B}), \\] \\[ \\frac{\\mathcal{B}(B^0 \\rightarrow \\psi(2S) \\pi^+ \\pi^-)}{\\mathcal{B}(B^0 \\rightarrow J/\\psi \\pi^+ \\pi^-)} =0.56\\pm0.07\\,(stat)\\pm0.05\\,(syst)\\pm0.01\\,(\\mathcal{B}), \\] \\[ \\frac{\\mathcal{B}(B^0_s \\rightarrow \\psi(2S) \\pi^+ \\pi^-)}{\\mathcal{B}(B^0_s \\rightarrow J/\\psi \\pi^+ \\pi^-)} =0.34\\pm0.04\\,(stat)\\pm0.03\\,(syst)\\pm0.01\\,(\\mathcal{B}), \\] where the third uncertainty corresponds to the ...

  9. Chemical composition and sources of PM1 and PM2.5 in Beijing in autumn.

    Science.gov (United States)

    Zhang, Yanyun; Lang, Jianlei; Cheng, Shuiyuan; Li, Shengyue; Zhou, Ying; Chen, Dongsheng; Zhang, Hanyu; Wang, Haiyan

    2018-02-20

    Beijing, the capital of China, suffers from severe atmospheric aerosol pollution; nevertheless, a comprehensive study of the constituents and sources of PM 1 is still lacking, and the differences between PM 1 and PM 2.5 are still unclear. In this study, an intensive observation was conducted to reveal the pollution characteristics of PM 1 and PM 2.5 in Beijing in autumn. Positive matrix factorization (PMF), backward trajectories and a potential source contribution function (PSCF) model were used to identify the source categories and source areas of PM 1 and PM 2.5 . The results showed that the average concentrations of PM 1 and PM 2.5 reached 78.20μg/m 3 and 95.47μg/m 3 during the study period, respectively. PM 1 contributed greatly to PM 2.5 . The PM 1 /PM 2.5 value increased from 73.6% to 90.1% with PM 1 concentration growing from 150μg/m 3 . Higher secondary inorganic aerosol (SIA) proportions (31.3%-70.8%) were found in PM 1 . The higher fraction of SIA, OC, EC and typical elements in PM 1 illustrated that anthropogenic components accumulated more in smaller size particles. Three typical weather patterns causing the heavy pollution in autumn were found as follows: (1) Siberian high and uniform high pressure field, (2) cold front and low-voltage system, and (3) uniform low pressure field. A PMF analysis indicated that secondary aerosols and coal combustion, vehicle, industry, biomass burning, and dust were the important sources of PM, accounting for 53.8%, 8.0%, 13.0%, 13.2% and 12.0% of PM 1 , respectively, and for 47.5%, 9.9%, 12.4%, 8.4% and 21.8% of PM 2.5 , respectively. The HYSPLIT and chemical components analysis indicated the potential contribution from biomass burning and fertilization ammonia emissions to PM 1 in autumn. The source areas were similar for PM 1 and PM 1-2.5 under general polluted conditions, but during the heavily polluted periods, the source areas were distributed in farther regions from Beijing for PM 1 than for PM 1-2.5 . Copyright

  10. Search for New Physics in the B02→J/ΨΦ and B02→ΦΦ Decays at CDF

    Energy Technology Data Exchange (ETDEWEB)

    Dorigo, Mirco [Univ. of Trieste (Italy)

    2012-12-01

    We present a search for physics beyond the standard model (SM) through a measurement of the violation of the charge-parity (CP) symmetry in two decays of the B02 meson using data collected by the Collider Detector at Fermilab (CDF) in proton-antiproton collisions at the center-of-mass energy of 1.96TeV. We exploit the decays B02→J/Ψ(→ μ+μ-)(→ K+K-) and B02→Φ (→ K+K-)Φ(→ K+K-), for which the SM accurately predicts very small or vanishing CP violation; both decay modes are very sensitive to new sources of CP violation expected in a broad class of SM extensions. We analyze the time-dependent CP asymmetry of the B02→J/ΨΦ decays collected in the full CDF Run II dataset for providing the final measurement of the B02B02 mixing phase, 2βs, and we present the first measurement of CP violation in B02→ΦΦ decays, through the determination of two time-integrated CP asymmetries, Av and Au, using an original method developed in this work. We find: -0.06 < βs < 0.30 at the 68% confidence level; Av = (-12.0 ± 6.4(stat) ± 1.6(syst))%; and Au = (-0.7 ± 6.4(stat) ± 1.8(syst))%. In addition, we provide measurements of the decay width difference between the light and heavy mass eigenstates of the B02 meson,ΔΓs 0.068 ± 0.026(stat) ± 0.009(syst) ps-1; and of their mean lifetime, τs = 1.528 ± 0.019(stat) ± 0.009(syst) ps. All results are among the most precise determinations from a single experiment and exhibit an excellent agreement with the SM predictions.

  11. Increase of vitamin D2 by UV-B exposure during the growth phase of white button mushroom (Agaricus bisporus)

    DEFF Research Database (Denmark)

    Kristensen, Hanne; Rosenqvist, Eva S. K.; Jakobsen, Jette

    2012-01-01

    Background: Mushrooms are the only non-animal food source of vitamin D. Wild mushrooms have naturally high vitamin D2 content, and cultivated mushrooms produce vitamin D2 from ergosterol when exposed to supplementary UV-B during the post-harvest phase. Objectives: This study investigated...... with exposure to supplementary UV-B just prior to harvest in the range of 0-2,400 mJ cm-2. Mushrooms grew for 2 days with or without repeated UV-B exposure each day. Vitamin D2 and growth rate were determined. Some mushrooms were post-harvest treated by exposure at 200 mJ cm-2 supplementary UV-B or natural...... sunlight, prior to vitamin D2 determination. Results: The content of vitamin D2 was 0.2-164 µg 100 g-1 fresh weight (FW), and there was a linear relationship between UV-dose up to 1,000 mJ cm-2 and vitamin D2 content. The fast growth rate of the mushrooms diluted the vitamin D2 from 24 to 3 µg 100 g-1...

  12. PODAAC-RSX12-L2B11

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset contains the RapidScat Level 2B 12.5km Version 1.1 science-quality ocean surface wind vectors. The Level 2B wind vectors are binned on a 12.5 km Wind...

  13. A study of the higher excitation levels of 11B via the 10B(n,n)10B and 10B(n,n')10B*(0.72, 1.74, 2.15, 3.59, 4.77 MeV) reactions

    International Nuclear Information System (INIS)

    Sadowski, E.T.

    1988-11-01

    As part of the study of the higher energy-level structure of 11 B, cross sections for elastic and inelastic scattering of neutrons from isotopically enriched 10 B samples have been measured for incident neutron energies from 3.03 MeV to 6.45 MeV in 250 keV increments and from 7.02 MeV to 12.01 MeV in 500 keV increments. Inelastic angular distributions for scattering to the states in parentheses in 10 B have been measured from the indicated energy up to 12.01 MeV; (0.718) from 3.02 MeV; (1.74) from 3.27 MeV; (2.15) from 3.77 MeV; (3.59) from 5.52 MeV; (4.77) from 7.02 MeV. The measurements at 3.02, 3.51, 4.02, and 4.51 MeV were done at nine laboratory angles from 20/degree/ to 158/degree/ in 17.5/degree/ increments with a sample that is isotopically 95.86% 10 B. All other distributions measured scattering at 11 laboratory angles from 18/degree/ to 158/degree/ in 15/degree/ increments from a sample that is isotopically 99.49% 10 B. The data are corrected for air scattering, sample attenuation, minor isotope impurity, multiple scattering, and elastic and inelastic scattering from the sample of the neutron source continuum and contaminants. An eight-channel, multilevel R-matrix analysis was performed on the data. Level energies, spins, and parities were deduced for twelve levels above 13 MeV excitation in 11 B. Only two definite and three tentative assignments for T = /1/2/ levels had been made previously above 13 MeV. The two definite levels were confirmed. Good agreement between the data and the R-matrix calculation in all analyzed channels was obtained for the proposed structure. 122 refs., 40 figs., 7 tabs

  14. Natively oxidized amino acid residues in the spinach cytochrome b 6 f complex.

    Science.gov (United States)

    Taylor, Ryan M; Sallans, Larry; Frankel, Laurie K; Bricker, Terry M

    2018-01-29

    The cytochrome b 6 f complex of oxygenic photosynthesis produces substantial levels of reactive oxygen species (ROS). It has been observed that the ROS production rate by b 6 f is 10-20 fold higher than that observed for the analogous respiratory cytochrome bc 1 complex. The types of ROS produced (O 2 •-, 1 O 2 , and, possibly, H 2 O 2 ) and the site(s) of ROS production within the b 6 f complex have been the subject of some debate. Proposed sources of ROS have included the heme b p , PQ p •- (possible sources for O 2 •- ), the Rieske iron-sulfur cluster (possible source of O 2 •- and/or 1 O 2 ), Chl a (possible source of 1 O 2 ), and heme c n (possible source of O 2 •- and/or H 2 O 2 ). Our working hypothesis is that amino acid residues proximal to the ROS production sites will be more susceptible to oxidative modification than distant residues. In the current study, we have identified natively oxidized amino acid residues in the subunits of the spinach cytochrome b 6 f complex. The oxidized residues were identified by tandem mass spectrometry using the MassMatrix Program. Our results indicate that numerous residues, principally localized near p-side cofactors and Chl a, were oxidatively modified. We hypothesize that these sites are sources for ROS generation in the spinach cytochrome b 6 f complex.

  15. IAU 2015 Resolution B2 on Recommended Zero Points for the Absolute and Apparent Bolometric Magnitude Scales

    DEFF Research Database (Denmark)

    Mamajek, E. E.; Torres, G.; Prsa, A.

    2015-01-01

    The XXIXth IAU General Assembly in Honolulu adopted IAU 2015 Resolution B2 on recommended zero points for the absolute and apparent bolometric magnitude scales. The resolution was proposed by the IAU Inter-Division A-G Working Group on Nominal Units for Stellar and Planetary Astronomy after...... consulting with a broad spectrum of researchers from the astronomical community. Resolution B2 resolves the long-standing absence of an internationally-adopted zero point for the absolute and apparent bolometric magnitude scales. Resolution B2 defines the zero point of the absolute bolometric magnitude scale...... such that a radiation source with $M_{\\rm Bol}$ = 0 has luminosity L$_{\\circ}$ = 3.0128e28 W. The zero point of the apparent bolometric magnitude scale ($m_{\\rm Bol}$ = 0) corresponds to irradiance $f_{\\circ}$ = 2.518021002e-8 W/m$^2$. The zero points were chosen so that the nominal solar luminosity (3.828e26 W...

  16. Effects of TiB2 Particle and Short Fiber Sizes on the Microstructure and Properties of TiB2-Reinforced Composite Coatings

    Science.gov (United States)

    Lin, Yinghua; Yao, Jianhua; Wang, Liang; Zhang, Qunli; Li, Xueqiao; Lei, Yongping; Fu, Hanguang

    2018-03-01

    In this study, particle and short fiber-reinforced titanium matrix composite coatings are prepared via laser in situ technique using (0.5 and 50 μm) TiB2 and Ti powder as cladding materials. The microstructure and properties of the composite coatings are studied, and the changing mechanism of the microstructure is discussed. The results reveal that particle agglomeration is prone to appear with using fine TiB2 particles. Decomposition of the particles preferentially occurs with using coarse TiB2 particles. The cracks and pores on the surface of the coating are formed at a lower laser energy density. With the increase in the laser energy density, cracking on the surface of the coating diminishes, but the coating exhibits depression behavior. The depression extent of the coating using fine TiB2 particle as the reinforcement is much less than that of the coating using coarse TiB2 particle. Moreover, the size of the aggregate and the tendency of cracking can be reduced with the increase in Ti addition. Meanwhile, short TiB fiber bundles are formed by the diffusion mechanism of rod aggregate, and randomly oriented TiB short fibers are formed mainly by the dissolution-precipitation mechanism of fine TiB2 particles. Moreover, the growth of short TiB fibers can be in an alternating manner between B27 and Bf structures. The micro-hardness and wear resistance of the coatings are evidently higher than that of the titanium alloy substrate. The wear resistance of the large size TiB2 coating is higher than that of the small size TiB2 coating under the condition of low load.

  17. Debesų kompiuterijos paslaugų teikimo optimizavimas B2B modelyje

    OpenAIRE

    Ciechanavičiūtė, Kamilė

    2017-01-01

    The optimization of cloud computing provision in a Business to Business (B2B) model is highly desirable in today’s dynamic global business environment. The business workflows between business partners, suppliers and consumers need to be highly adaptable to changing business needs. As businesses move from a static to a dynamic environment, cloud computing provides a highly scalable, elastic and cost effective compute platform to run both, traditional platform 2 applications as well as the plat...

  18. Self-assembly of Polystyrene- b -poly(2-vinylpyridine)- b -poly(ethylene oxide) Triblock Terpolymers

    KAUST Repository

    Musteata, Valentina-Elena; Sutisna, Burhannudin; Polymeropoulos, Georgios; Avgeropoulos, Apostolos; Meneau, Florian; Peinemann, Klaus-Viktor; Hadjichristidis, Nikolaos; Nunes, Suzana Pereira

    2017-01-01

    Polystyrene-b-poly(2-vinylpyridine)-b-poly(ethylene oxide) (PS-b-P2VP-b-PEO) terpolymer is a versatile polymer to form isoporous films and membranes, due to the possibility of self-assembly control and the properties of the different blocks, such as the P2VP ability of complexation, and H-bond formation, and the PEO biocompatibility. Copolymers with different block ratios and sizes were synthesized. The correlation between their equilibrium bulk morphology, the self-assembly in dilute and semi-dilute solutions and the non-equilibrium porous structures of membranes, obtained by non-solvent induced phase separation, was investigated and discussed in detail. The characterization was performed by small-angle X-ray scattering (SAXS), scanning (SEM) and transmission electron microscopy (TEM). Hexagonal, cubic and lamellar arrangements were observed. The preparation conditions were optimized and a regular, isoporous morphology, suitable for membrane application, was successfully obtained with PS80.5k-b-P2VP64.4k-b-PEO16.1k.

  19. Self-assembly of Polystyrene- b -poly(2-vinylpyridine)- b -poly(ethylene oxide) Triblock Terpolymers

    KAUST Repository

    Musteata, Valentina-Elena

    2017-11-08

    Polystyrene-b-poly(2-vinylpyridine)-b-poly(ethylene oxide) (PS-b-P2VP-b-PEO) terpolymer is a versatile polymer to form isoporous films and membranes, due to the possibility of self-assembly control and the properties of the different blocks, such as the P2VP ability of complexation, and H-bond formation, and the PEO biocompatibility. Copolymers with different block ratios and sizes were synthesized. The correlation between their equilibrium bulk morphology, the self-assembly in dilute and semi-dilute solutions and the non-equilibrium porous structures of membranes, obtained by non-solvent induced phase separation, was investigated and discussed in detail. The characterization was performed by small-angle X-ray scattering (SAXS), scanning (SEM) and transmission electron microscopy (TEM). Hexagonal, cubic and lamellar arrangements were observed. The preparation conditions were optimized and a regular, isoporous morphology, suitable for membrane application, was successfully obtained with PS80.5k-b-P2VP64.4k-b-PEO16.1k.

  20. A Cross-Industry Review of B2B Critical Success Factors.

    Science.gov (United States)

    Eid, Riyad; Trueman, Myfanwy; Ahmed, Abdel Moneim

    2002-01-01

    Presents a comprehensive review of B2B (business-to- business) international Internet marketing and identifies 21 critical success factors in five categories: marketing strategy, including management support, strategic goals, and collaboration; Web site factors, including Web site design; global factors, including multilanguage sites and cultural…

  1. Laser cladding of aluminium using TiB2

    CSIR Research Space (South Africa)

    Kumar, S

    2010-03-01

    Full Text Available to that of steel (5) and Tita- nium (6; 7). Previous work con- sists of an effort to make deep laser injection of TiB2 on Al or the creation of in-situ of TiB2 using other reactant particles. In-situ creation of TiB2 suffers from other side effects...

  2. Study on hybrid heat source overlap welding of magnesium alloy AZ31B

    International Nuclear Information System (INIS)

    Liang, G.L.; Zhou, G.; Yuan, S.Q.

    2009-01-01

    The magnesium alloy AZ31B was overlap welded by hybrid welding (laser-tungsten inert gas arc). According to the hybrid welding interaction principle, a new heat source model, hybrid welding heat source model, was developed with finite element analysis. At the same time, using a high-temperature metallographical microscope, the macro-appearance and microstructure characteristics of the joint after hybrid overlap welding were studied. The results indicate that the hybrid welding was superior to the single tungsten inert gas welding or laser welding on the aspects of improving the utilized efficiency of the arc and enhancing the absorptivity of materials to laser energy. Due to the energy characteristics of hybrid overlap welding the macro-appearance of the joint was cup-shaped, the top weld showed the hybrid welding microstructure, while, the lower weld showed the typical laser welding microstructure

  3. Study on hybrid heat source overlap welding of magnesium alloy AZ31B

    Energy Technology Data Exchange (ETDEWEB)

    Liang, G.L. [Department of Electromechanical Engineering, Tangshan College, Tangshan 063000 (China)], E-mail: guoliliang@sohu.com; Zhou, G. [School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Yuan, S.Q. [Department of Electromechanical Engineering, Tangshan College, Tangshan 063000 (China)

    2009-01-15

    The magnesium alloy AZ31B was overlap welded by hybrid welding (laser-tungsten inert gas arc). According to the hybrid welding interaction principle, a new heat source model, hybrid welding heat source model, was developed with finite element analysis. At the same time, using a high-temperature metallographical microscope, the macro-appearance and microstructure characteristics of the joint after hybrid overlap welding were studied. The results indicate that the hybrid welding was superior to the single tungsten inert gas welding or laser welding on the aspects of improving the utilized efficiency of the arc and enhancing the absorptivity of materials to laser energy. Due to the energy characteristics of hybrid overlap welding the macro-appearance of the joint was cup-shaped, the top weld showed the hybrid welding microstructure, while, the lower weld showed the typical laser welding microstructure.

  4. The 2-ID-B intermediate-energy scanning X-ray microscope at the APS

    International Nuclear Information System (INIS)

    McNulty, I.; Paterson, D.; Arko, J.; Erdmann, M.; Goetze, K.; Ilinski, P.; Mooney, T.; Vogt, S.; Xu, S.; Frigo, S.P.; Stampfl, A.P.J.; Wang, Y.

    2002-01-01

    The intermediate-energy scanning x-ray microscope at beamline 2-ID-B at the Advanced Photon Source is a dedicated instrument for materials and biological research. The microscope uses a zone plate lens to focus coherent 1-4 keV x-rays to a 60 nm focal spot of 10 9 photons/s onto the sample. It records simultaneous transmission and energy-resolved fluorescence images. We have used the microscope for nano-tomography of chips and micro-spectroscopy of cells. (authors)

  5. Matchmaking Framework for B2B E-Marketplaces

    Directory of Open Access Journals (Sweden)

    Fekete ZOLTAN ALPAR

    2010-01-01

    Full Text Available In the recent years trading on the Internet become more popular. Online businesses gradually replace more and more from the conventional business. Much commercial information is exchanged on the internet, especially using the e-marketplaces. The demand and supply matching process becomes complex and difficult on last twenty years since the e-marketplaces play an important role in business management. Companies can achieve significant cost reduction by using e-marketplaces in their trade activities and by using matchmaking systems on finding the corresponding supply for their demand and vice versa. In the literature were proposed many approaches for matchmaking. In this paper we present a conceptual framework of matchmaking in B2B e-marketplaces environment.

  6. OsB 2 and RuB 2, ultra-incompressible, hard materials: First-principles electronic structure calculations

    Science.gov (United States)

    Chiodo, S.; Gotsis, H. J.; Russo, N.; Sicilia, E.

    2006-07-01

    Recently it has been reported that osmium diboride has an unusually large bulk modulus combined with high hardness, and consequently is a most interesting candidate as an ultra-incompressible and hard material. The electronic and structural properties of the transition metal diborides OsB 2 and RuB 2 have been calculated within the local density approximation (LDA). It is shown that the high hardness is the result of covalent bonding between transition metal d states and boron p states in the orthorhombic structure.

  7. Microhardness and microstructure evolution of TiB2 reinforced Inconel 625/TiB2 composite produced by selective laser melting

    Science.gov (United States)

    Zhang, Baicheng; Bi, Guijun; Nai, Sharon; Sun, Chen-nan; Wei, Jun

    2016-06-01

    In this study, micron-size TiB2 particles were utilized to reinforce Inconel 625 produced by selective laser melting. Exceptional microhardness 600-700 HV0.3 of the composite was obtained. In further investigation, the microstructure and mechanical properties of Inconel 625/TiB2 composite can be significantly influenced by addition of TiB2 particles during SLM. It was found that the long directional columnar grains observed from SLM-processed Inconel 625 were totally changed to fine dendritic matrix due to the addition of TiB2 particles. Moreover, with laser energy density (LED) of 1200 J/m, a Ti, Mo rich interface around TiB2 particles with fine thickness can be observed by FESEM and EDS. The microstructure evolution can be determined by different laser energy density (LED): under 1200 J/m, γ phase in dendrite grains; under 600 J/m, γ phase in combination of dendritic and acicular grains; under 400 J/m, γ phase acicular grains. Under optimized LED 1200 J/m, the dynamic nanohardness (8.62 GPa) and elastic modulus (167 GPa) of SLM-processed Inconel 625/TiB2 composite are higher compared with those of SLM-processed Inconel 625 (3.97 GPa and 135 GPa, respectively).

  8. Ia-restricted B-B cell interaction. I. The MHC haplotype of bone marrow cells present during B cell ontogeny dictates the self-recognition specificity of B cells in the polyclonal B cell activation by a B cell differentiation factor, B151-TRF2

    International Nuclear Information System (INIS)

    Ono, S.; Takahama, Y.; Hamaoka, T.

    1987-01-01

    We have demonstrated that B cell recognition of Ia molecules is involved in polyclonal B cell differentiation by B151-TRF2. The present study was undertaken to examine the Ia recognition specificity of B151-TRF2-responsive B cells in fully major histocompatibility complex (MHC)-allogeneic P1----P2, semiallogeneic P1----(P1 x P2)F1, and double donor (P1 + P2)----(P1 x P2)F1 and (P1 + P2)----P1 radiation bone marrow chimeras. The B cells from both P1----P2 and P1----(P1 x P2)F1 chimeras could give rise to in vitro immunoglobulin M-producing cells upon stimulation with B151-TRF2 comparable in magnitude to that of normal P1 B cells, and their responses were inhibited by anti-I-AP1 but not by anti-I-AP2 monoclonal antibody even in the presence of mitomycin C-treated T cell-depleted P2 spleen cells as auxiliary cells. In contrast, the B151-TRF2 responses of P1 B cells isolated from both (P1 + P2)----(P1 x P2)F1 and (P1 + P2)----P1 double bone marrow chimeras became sensitive to the inhibition of not only anti-I-AP1 but also anti-I-AP2 monoclonal antibody only when the culture was conducted in the presence of P2 auxiliary cells, demonstrating that they adaptively differentiate to recognize as self-structures allogeneic as well as syngeneic Ia molecules. Moreover, the experiments utilizing B cells from H-2-congenic mice and B cell hybridoma clones as auxiliary cells revealed that B151-TRF2-responsive B cells recognize Ia molecules expressed on B cells. Taken together, these results demonstrate that B151-TRF2-responsive B cells recognize Ia molecules expressed by B cells as self-structures and that their self-recognition specificity is dictated by the MHC haplotype of bone marrow cells present during the B cell ontogeny but not by the MHC haplotype of a radiation-resistant host environment

  9. Theoretical study of the ionization of B2H5

    International Nuclear Information System (INIS)

    Curtiss, L.A.; Pople, J.A.

    1989-01-01

    Ab initio molecular orbital calculations at the G1 level of theory have been carried out on neutral B 2 H 5 radical, doubly bridged B 2 H + 5 cation, and the first triplet excited state of B 2 H + 5 . Singly bridged B 2 H 5 is 4.0 kcal/mol (without zero-point energies) more stable than doubly bridged B 2 H 5 . Based on this work and previous theoretical work on triply bridged B 2 H + 5 , ionization potentials (vertical and adiabatic) are determined for B 2 H 5 . The adiabatic ionization potentials of the two B 2 H 5 structures are 6.94 eV (singly bridged) and 7.53 eV (doubly bridged). A very large difference is found between the vertical and adiabatic ionization potentials (3.37 eV) of the singly bridged B 2 H 5 structure. The first triplet state of B 2 H + 5 is found to be 4.55 eV higher in energy than the lowest energy B 2 H + 5 cation (triply bridged). The results of this theoretical study support the interpretation of Ruscic, Schwarz, and Berkowitz of their recent photoionization measurements on B 2 H 5

  10. Morphology-control of VO2 (B) nanostructures in hydrothermal synthesis and their field emission properties

    International Nuclear Information System (INIS)

    Yin Haihong; Yu Ke; Zhang Zhengli; Zhu Ziqiang

    2011-01-01

    VO 2 (B) nanostructures were synthesized via a facile hydrothermal process using V 2 O 5 as source material and oxalic acid as reductant. Three nanostructures of nanorods, nanocarambolas and nanobundles were found existing in the products, and a continuous changing of morphology was found in the synthesis process, during which the proportion of these three types of nanostructures can be adjusted by altering the concentrations of oxalic acid. The microstructures were evaluated using X-ray diffraction and scanning and transmission electron microscopies, respectively. FE properties measurement of these three types of nanostructures showed that the nanobundles have the best field emission performance with a turn-on field of ∼1.4 V/μm and a threshold field of ∼5.38 V/μm. These characteristics make VO 2 (B) nanostructures a competitive cathode material in field emission devices.

  11. A Model-based B2B (Batch to Batch) Control for An Industrial Batch Polymerization Process

    Science.gov (United States)

    Ogawa, Morimasa

    This paper describes overview of a model-based B2B (batch to batch) control for an industrial batch polymerization process. In order to control the reaction temperature precisely, several methods based on the rigorous process dynamics model are employed at all design stage of the B2B control, such as modeling and parameter estimation of the reaction kinetics which is one of the important part of the process dynamics model. The designed B2B control consists of the gain scheduled I-PD/II2-PD control (I-PD with double integral control), the feed-forward compensation at the batch start time, and the model adaptation utilizing the results of the last batch operation. Throughout the actual batch operations, the B2B control provides superior control performance compared with that of conventional control methods.

  12. Observation of B+ -> J/psi 3 pi(+)2 pi(-) and B+ -> psi (2S)pi(+)pi(+)pi(-) decays

    NARCIS (Netherlands)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M. H.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A. Jr; Amato, S.; Amerio, S.; Amhis, Y.; BEACH, LA; Anderlini, L.; Andreassi, G.; Andreotti, M.; Andrews, J.E.; Appleby, R.B.; Archilli, F.; d'Argent, P.; Romeu, J. Arnau; Artamonov, AY; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Babuschkin, I.; Bachmann, S; Back, Jaap Willem; Badalov, A.; Baesso, C.; Baker, S; Baldini, W.; Barlow, R.J.; Barschel, C.; Barsuk, S.; Barter, W.; Baszczyk, M.; Batozskaya, V.; Batsukh, B.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Bellee, V.; Belloli, N.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Castano-Betancourt, Martha; Betti, F.; Bettler, M.O.; van Beuzekom, MG; Bezshyiko, Ia; Bifani, S.; Billoir, P.; Bird, T.; Birnkraut, A.; Bitadze, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Boettcher, Thomas; Bondar, A.; Bondar, N.; Bonivento, W.; Bordyuzhin, I.; Borgheresi, A.; Borghi, S.; Borisyak, M.; Borsato, M.; Bossu, F.; Boubdir, M.; Bowcock, T. J. V.; Bowen, D.E.; Bozzi, C.; Braun, S.; Britsch, M.; Britton, T.; Brodzicka, J.; Buchanan, E.; Burr, C.; Bursche, A.; Buytaert, R. J.; Cadeddu, S.; Calabrese, J. R.; Calvi, M.; Gomez, M. Calvo; Camboni, A.; Campana, P.; Perez, D. H. Campora; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Akiba, K. Carvalho; Casse, G.; Cassina, L.; Garcia, L. Castillo; Cattaneo, M.; Cauet, Ch.; Cavallero, G.; Cenci, R.; Charles, M; Charpentier, Ph.; Chatzikonstantinidis, G.; Chefdeville, M.; Chen, S.; Cheung, T.F.S.; Chobanova, V.; Chrzaszcz, M.; Vidal, X. Cid; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; COOK, AM; Coombs, Geoffrey W.; Coquereau, S.; Corti, G.; Corvo, M.; Sobral, C. M. Costa; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A. C.; Torres, M. Cruz; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Marinho, F. Da Cunha; Dall'Occo, E.; Dalseno, J.; David, P. N. Y.; Davis, A.; Francisco, O. De Aguiar; De Bruyn, K.; De Capua, S.; De Cian, M.; Miranda, J. M.; De Paula, L.; De Serio, M.; De Simone, Paolo; Dean, C. -T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Demmer, M.; Dendek, A.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Dijkstra, H.; Dordei, F.; Dorigo, M.; Suarez, A. Dosil; Dovbnya, A.; Dreimanis, K.; Dufour, L.; Dujany, G.; Dungs, K.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Deleage, N.; Easo, S.; Ebert, Martin A.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; Ely, SIdi Ould; Esen, S.; Evans, Helen M.; Evans, T.; Falabella, A.; Farley, N.; Farry, S.; Fay, R. F.; Fazzini, D.; FERGUSON, D; Prieto, A. Fernandez; Ferrari, F; Rodrigues, F. Ferreira; Ferro-Luzzi, M.; Filippov, S.; Fini, R. A.; Fiore, M; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fleuret, F.; Fohl, K; Fontana, M.; Fontanelli, F.; Forshaw, D. C.; Forty, R.; Lima, V. Franco; Frank, M.; Frei, C.; Fu, J.; Furfaro, E.; Farber, CR; Torreira, A. Gallas; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; Martin, L. M. Garcia; Pardinas, J. Garcia; Tico, J. Garra; Garrido, L.; Garsed, P. J.; Gascon, D.; Gaspar, C; Gavardi, L.; Gazzoni, G.; Gerick, D.; Gersabeck, E. G; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Giani', S.; Gibson, V.; Girard, O. G.; Giubega, L.; Gizdov, K.; Gligorov, V. V.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gorelov, I. V.; Gotti, C.; Govorkova, E.; Gandara, M. Grabalosa; Diaz, R. Graciani; Cardoso, L. A. Granado; Grauges, E.; Graverini, E.; Graziani, G.; Grecu, A.; Griffith, P.; Grillo, L.; Cazon, B. R. Gruberg; Grunberg, O.; Gushchin, EM; Guz, Yu.; Gys, T.; Gobel, C.; Hadavizadeh, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, D.B.; Han, Xiaoyan; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, Christine J.; Hatch, M.; He, J. J.; Head, T.; Heister, J. A.; Hennessy, K.; Henrard, P.; Henry, Lee; Morata, J. A. Hernando; Van Herwijnen, E.; Hess, M.; Hicheur, A.; HILL, D; Hombach, C.; Hopchev, H.; Hulsbergen, W.; Humair, T.; Hushchyn, M.; Hussain, Sabah N. A.; Hutchcroft, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jawahery, A.; Jiang, Fuman; John, Jestinah M. Mahachie; Johnson, D; Jones, Jonathan C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Kariuki, J. M.; Karodia, S.; Kecke, M.; Kelsey, M.; Kenyon, I. R.; Kenzie, M.; Ketel, T. J.; Khairullin, E.; Khanji, B.; Khurewathanakul, C.; Kirn, T.; Klaver, N. S.; Klimaszewski, K.; Koliiev, S.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Kosmyntseva, A.; Kozachuk, A.; Kozeiha, M.; Kravchuk, Vladimir Leonidovich; Kreplin, K.; Kreps, M.; Krokovny, P.; Kruse, F.; Krzemien, W.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kuonen, A. K.; Kurek, K.; Kvaratskheliya, T.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lanfranchi, G.; Langenbruch, C.; Latham, T.; Lazzeroni, C.; Le Gac, R.; Van Leerdam, J.; Lees, J. -P.; Leflat, A.; Lefrancois, J.; Lefevre, R.; Lemaitre, F.; Cid, E. Lemos; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y; Likhomanenko, T.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Liu, X.; Loh, D.; Longstaff, I.; Lopes, J. H.; Lucchesi, D.; Lucio Martinez, M.; Luo, Haibin; Lupato, A.; Luppi, E.; Lupton, O.; Lusiani, A.; Lyu, X. R.; Machefert, F.; Maciuc, F.; Maev, O.; Maguire, Kate; Malde, S.; Malinin, A.; Maltsev, T.; Manca, G.; Mancinelli, G.; Manning, P.; Maratas, J.; Marchand, J. F.; Marconi, U.; Benito, C. Marin; Marino, Paolo; Marks, J. D.; Martellotti, G.; Martin, M.; Martinelli, M.; Santos, D. Martinez; Vidal, F. Martinez; Tostes, D. Martins; Massacrier, L. M.; Massafferri, A.; Matev, R.; Mathad, A.; Mathe, Z.; Matteuzzi, C.; Mauri, A.; Maurin, B.; Mazurov, A.; McCann, Linda M.; McCarthy, Patrick J.; McNab, A.; McNulty, R.; Meadows, B.; Meier, F.; Meissner, M.; Melnychuk, D.; Merk, M.; Merli, A.; Michielin, E.; Milanes, D. A.; Minard, M. -N.; Mitzel, D. S.; Mogini, A.; Rodriguez, J. Molina; Moreno-Monroy, Ana I.; Monteil, S.; Morandin, M.; Morawski, P.; Morda, A.; Morello, M. J.; Moron, J.; Morris, A. -B.; Mountain, R.; Muheim, F.; Mulder, M; Mussini, M.; Muller, D.; Muller, J.; Muller, K; Muller, V; Naik, P.; Nakada, T.; Nandakumar, R.; Nandi, A.; Nasteva, I.; Needham, M.; Neri, N.; Neubert, S.; Neufeld, N.; Neuner, M.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Nieswand, S.; Niet, R.; Nikitin, N.; Nikodem, T.; Novoselov, A.; O'Hanlon, D. P.; Oblakowska-Mucha, A.; Obraztsov, V.; Ogilvy, S.; Oldeman, R.; Onderwater, C. J. G.; Goicochea, J. M. Otalora; Otto, A.; Owen, Randall P.; Oyanguren, A.; Pais, P. R.; Palano, A.; Palombo, F.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Pappalardo, L.; Parker, Anthony W.; Parkes, C.; Passaleva, G.; Pastore, A.; Patel, G. D.; Patel, M.; Patrignani, C.; Pearce, A.; Pellegrino, A.; Penso, G.; Altarelli, M. Pepe; Perazzini, S.; Perret, P.; Pescatore, L.; Petridis, K.; Petrolini, A.; Petrov, A. D.; Petruzzo, M.; Olloqui, E. Picatoste; Pietrzyk, B.; Pikies, M.; Pinci, D.; Pistone, A.; Piucci, A.; Playfer, S.; Casasus, M. Plo; Poikela, T.; Polci, F.; Poluektov, A.; Polyakov, I.; Polycarpo, E.; Pomery, G. J.; Popov, A.; Popov, D.; Popovici, B.; Poslavskii, S.; Potterat, C.; Price, P. E.; Price, Daniel J.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Navarro, A. Puig; Punzi, G.; Qian, S. W.; Quagliani, R.; Rachwal, B.; Rademacker, J. H.; Rama, M.; Pernas, M. Ramos; Rangel, M. S.; Raniuk, I.; Ratnikov, F.; Raven, G.; Redi, F.; Reichert, Andreas S.; Dos Reis, A. C.; Alepuz, C. Remon; Renaudin, V.; Ricciardi, S.; Richards, S.; Rihl, M.; Rinnert, K.; Molina, V. Rives; Robbe, P.; Rodrigues, A. B.; Rodrigues, Eliane R.; Lopez, J. A. Rodriguez; Perez, P. Rodriguez; Rogozhnikov, A.; Roiser, S.; Rollings, A.; Romanovskiy, V.; Vidal, A. Romero; Ronayne, J. W.; Rotondo, M.; Ruf, Thomas; Valls, P. Ruiz; Silva, J. J. Saborido; Sadykhov, E.; Sagidova, N.; Saitta, B.; Guimaraes, V. Salustino; Mayordomo, C. Sanchez; Sedes, B. Sanmartin; Santacesaria, R.; Rios, C. Santamarina; Santimaria, M.; Santovetti, E.; Sarti, A.; Satriano, C.; Satta, A.; Saunders, D. M.; Savrina, D.; Schael, S.; Schellenberg, M.; Schiller, M.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmelzer, T.; Schmidt, B.; Schneider, O.; Schopper, A.; Schubert, K.; Schubiger, M.; Schune, M. -H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Semennikov, A.; Sergi, A.; Serra, N.; Gonzalez-Serrano, J.; Sestini, L.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, V.; Siddi, B. G.; Coutinho, R. Silva; Oliveira, L. Silva de; Simi, G.; Simone Doolaard, [No Value; Sirendi, M.; Skidmore, N.; Skwarnicki, T.; Smith, E.; Smith, I. T.; Smith, J; Smith, M; Snoek, H.; Sokoloff, M. D.; Soler, F. J. P.; De Paula, B. Souza; Spaan, B.; Spradlin, P.; Sridharan, S.; Stagni, F.; Stahl, M.; Stahl, Sherin S.; Stefko, P.; Stefkova, S.; Steinkamp, O.; Stemmle, S.; Stenyakin, O.; Stevenson, S.; Stoica, S.; Stone, Ian S.; Storaci, B.; Stracka, S.; Straticiuc, M.; Straumann, U.; Sun, L.; Sutcliffe, W.; Swientek, K.; Syropoulos, V.; Szczekowski, M.; Szumlak, T.; T'Jampens, S.; Tayduganov, A.; Tekampe, T.; Tellarini, G.; Teubert, F.; Thomas, E.; Tilburg, Jeroen J H C; Tilley, M. J.; Tisserand, V.; Tobin, M; Tolk, S.; Tomassetti, L.; Tonelli, D.; Topp-Joergensen, S.; Toriello, F.; Tournefier, E.; Tourneur, S.; Trabelsi, K.; Traill, M.; Tran, M. T.; Tresch, M.; Trisovic, A.; Tsaregorodtsev, A.; Tsopelas, P.; Tully, A.; Tuning, N.; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vacca, C.; Vagnoni, V.; Valassi, A.; Valat, S.; Valenti, G.; Vallier, A.; Gomez, R. Vazquez; Regueiro, P. Vazquez; Vecchi, S.; van Veghel, M.; Velthuis, Miranda J.; Veltri, M.; Veneziano, G.; Venkateswaran, A.; Vernet, M.; Vesterinen, M.; Viaud, B.; VIEIRA, DF; Diaz, M. Vieites; Viemann, H.; Vilasis-Cardona, X.; Vitti, M.; Volkov, V.; Vollhardt, A.; Voneki, B.; Vorobyev, A.; Vorobyev, V.; Voss, C.; de Vries, J. A.; Sierra, C. Vazquez; Waldi, R.; Wallace, C.; Wallace, R; Walsh, J.; Wang, J; Ward, D. R.; Wark, H. M.; Watson, N. K.; Websdale, D.; Weiden, A.; Whitehead, M.; Wicht, J.; Wilkinson, G.; Wilkinson, M.; Williams, M.; Williams, M.; Williams, M.; Williams, Tishan; Wilson, F. Perry; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wraight, K.; Wyllie, K.; Xie, Y; Xing, Zhe; Xu, Z.; Yang, Z.; Yin, H.; Yu, J.; Yuan, X.-L.; Yushchenko, O.; Zarebski, K. A.; Zavertyaev, M.; Zhang, L; Zhang, Y.; Zhang, Y.; Zhelezov, A.; Zheng, Y.; Zhokhov, A.; Zhu, X.; Zhukov, V.; Zucchelli, S.; Rudolph, M.S.

    2017-01-01

    The decays B+-> J/psi 3 pi(+)2 pi(-) and B+ -> psi(2S)pi(+)pi(+)pi(-) are observed for the first time using a data sample corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment in proton- proton collisions at the centre-of-mass energies of 7 and 8 TeV. The

  13. The Importance of Brand on B2B Markets: Expert Interviews with Hilti AG Managers

    Directory of Open Access Journals (Sweden)

    Martin Konečný

    2013-12-01

    Full Text Available This paper investigates the importance of brand building in the business-to-business world. Not only B2C companies must take branding into account and put it among their top priorities in order to survive and succeed on the market. The first part of the article deals with the theoretical background of brand importance and market specifics of B2B markets and results in the setting of two hypotheses. The following research has to find out how the managers of a pure business-to-business company perceive the importance of a brand; moreover, it has to evaluate the importance of eight specific brand building factors. Fourteen expert interviews document the growing of brands in the B2B market and their main aspects. At the end of the article, we will focus on future implications for B2B management.

  14. In vitro study of vitamins B1, B2 and B6 adsorption on zeolite

    OpenAIRE

    Basić Zorica; Kilibarda Vesna; Dobrić Silva; Resanović Radmila

    2011-01-01

    Background/Aim. Zeolites are the hydratised alumosilicates of alcali and earthalcali cations, which have a long three-dimensional crystal structure. Preparations on the basis of zeolites are used for adsorption of organic and nonorganic toxic substances and they, also, find more and more use in veterinary and human medicine and pharmacy. The aim of this study was to evaluate the possibilities of zeolite to adsorb vitamins B1, B2 and B6 in acid and neutral solutions, as well as the chara...

  15. Bradykinin B2 receptor expression in the bronchial mucosa of allergic asthmatics: the role of NF-kB.

    Science.gov (United States)

    Ricciardolo, F L M; Petecchia, L; Sorbello, V; Di Stefano, A; Usai, C; Massaglia, G M; Gnemmi, I; Mognetti, B; Hiemstra, P S; Sterk, P J; Sabatini, F

    2016-03-01

    Bradykinin (BK) mediates acute allergic asthma and airway remodelling. Nuclear factor-kappa B (NF-kB) is potentially involved in BK B2 receptor (B2R) regulation. In this observational cross-sectional study, B2R and NF-kB expression was evaluated in bronchial biopsies from mild asthmatics (after diluent/allergen challenge) and healthy controls, examining the role of NF-kB in B2R expression in primary human fibroblasts from normal and asthmatic subjects (HNBFb and HABFb). B2R and NF-kB (total and nuclear) expression was analysed by immunohistochemistry in biopsies from 10 mild intermittent asthmatics (48 h after diluent/allergen challenge) and 10 controls undergoing bronchoscopy. B2R co-localization in 5B5(+) and αSMA(+) mesenchymal cells was studied by immunofluorescence/confocal microscopy, and B2R expression in HABFb/HNBFb incubated with interleukin (IL)-4/IL-13 with/without BK, and after NF-kB inhibitor, by Western blotting. Bronchial mucosa B2R and nuclear NF-kB expression was higher in asthmatics after diluent (B2R only) and allergen challenge than in controls (P kB (total and nuclear) increased after allergen compared with after diluent (P kB inhibitor (P kB expression. NF-kB inhibitor blocked IL-4/IL-13-induced increase in B2R expression in cultured fibroblasts, suggesting a role as potential anti-asthma drug. © 2015 John Wiley & Sons Ltd.

  16. Accessibility of tyrosyl residues altered by formation of the histone 2A/2B complex

    International Nuclear Information System (INIS)

    Callaway, J.E.; Ho, Y.S.; DeLange, R.J.

    1985-01-01

    The availability of tyrosyl residues to surface iodination was analyzed for histone 2A (H2A), histone 2B (H2B), and the H2A/H2B complex. When H2A is free in solution (200 mM NaCl, pH 7.4) tyrosine-39 and one or both tyrosines-50 and -57 were readily iodinated. Tyrosines-83 and -121 of H2B were iodinated, both when the histone was free in solution and when it was associated with H2A, while tyrosines-37, -40, and -42 of H2B were not iodinated under either condition. When H2A and H2B were associated or covalently cross-linked, all tyrosyl residues of H2A were unavailable for iodination. The authors also found that the iodination of nondenatured H2A and H2B did not inhibit formation of the H2A/H2B complex. These results indicate that the amino-terminal regions of the hydrophobic portions of H2A and H2B undergo significant conformational changes upon formation of the H2A/H2B complex. These conformational shifts occur in the same region of the H2A/H2B complex that contains a contact site between H2A and H2B in the nucleosome, thus indicating an involvement of this region in chromatin assembly

  17. A Cross-Talk Between NFAT and NF-κB Pathways is Crucial for Nickel-Induced COX-2 Expression in Beas-2B Cells

    Science.gov (United States)

    Cai, T.; Li, X.; Ding, J.; Luo, W.; Li, J.; Huang, C.

    2013-01-01

    Cyclooxygenase-2 (COX-2) is a critical enzyme implicated in chronic inflammation-associated cancer development. Our studies have shown that the exposure of Beas-2B cells, a human bronchial epithelial cell line, to lung carcinogenic nickel compounds results in increased COX-2 expression. However, the signaling pathways leading to nickel-induced COX-2 expression are not well understood. In the current study, we found that the exposure of Beas-2B cells to nickel compounds resulted in the activation of both nuclear factor of activated T cell (NFAT) and nuclear factor-κB (NF-κB). The expression of COX-2 induced upon nickel exposure was inhibited by either a NFAT pharmacological inhibitor or the knockdown of NFAT3 by specific siRNA. We further found that the activation of NFAT and NF-κB was dependent on each other. Since our previous studies have shown that NF-κB activation is critical for nickel-induced COX-2 expression in Beas-2B cells exposed to nickel compounds under same experimental condition, we anticipate that there might be a cross-talk between the activation of NFAT and NF-κB for the COX-2 induction due to nickel exposure in Beas-2B cells. Furthermore, we showed that the scavenging of reactive oxygen species (ROS) by introduction of mitochondrial catalase inhibited the activation of both NFAT and NF-κB, and the induction of COX-2 due to nickel exposure. Taken together, our results defining the evidence showing a key role of the cross-talk between NFAT and NF-κB pathways in regulating nickel-induced COX-2 expression, further provide insight into the understanding of the molecular mechanisms linking nickel exposure to its lung carcinogenic effects. PMID:21486220

  18. PI-RADS version 2: evaluation of diffusion-weighted imaging interpretation between b = 1000 and b = 1500 s mm-2.

    Science.gov (United States)

    Kwon, Mi-Ri; Kim, Chan Kyo; Kim, Jae-Hun

    2017-11-01

    To investigate the variability of diffusion-weighted imaging (DWI) interpretation of Prostate Imaging Reporting and Data System (PI-RADS) version 2 (v2) in evaluating prostate cancer (PCa). 154 patients with PCa underwent multiparametric 3T MRI, followed by radical prostatectomy. DWI with different b values (b = 0, 100, 1000 and 1500 s mm - 2 ) was obtained. Using the PI-RADS v2, two radiologists independently scored suspicious lesions in each patient and compared DWI of b = 1000 (DWI 1000 ) with 1500 (DWI 1500 ) s mm - 2 . On DWI 1000 and DWI 1500 , the intermethod and interobserver agreements of DWI scores were excellent in all patients (κ ≥ 0.873). In each peripheral zone and transition zone DWI scores, both observers showed excellent intermethod agreement between DWI 1000 and DWI 1500 (κ ≥ 0.897), and interobserver agreement for DWI 1000 and DWI 1500 was good to excellent (κ ≥ 0.796). For estimating clinically significant cancer, the area under receiver operating characteristics curves of DWI 1000 and DWI 1500 were 0.710 and 0.724 for observer 1 (p = 0.11), and 0.649 and 0.656 for observer 2 (p = 0.12), respectively. The PI-RADS v2 scoring at 3T shows excellent agreement between DWI 1000 and DWI 1500 in evaluating PCa, with excellent inter-observer agreement. Advance in knowledge: DWI using b = 1000 s mm -2 instead of b = 1500 s mm -2 reduces examination time or image distortion, with improved the signal-to-noise ratio.

  19. Pseudopotential approach to superconductivity in MgB2

    International Nuclear Information System (INIS)

    Sharma, K.S.; Bhargava, Nidhi; Jain, Ritu; Goyal, Varsha; Sharma, Ritu; Sharma, Smita

    2010-01-01

    Superconductivity in MgB 2 has been re-examined in BCS-Eliashberg framework by employing Mc-Millan's T c -equation and form factors of MgB 2 computed from the form factors of component metals (Model-I). The empty core model pseudopotential due to Ashcroft and random phase approximation form of dielectric screening due to Gellmann and Brueckner are used in the present work. An excellent agreement between the present values and other theoretically computed values of T c and with the relevant experimental data for MgB 2 confirms the validity of the present approach. The explicit dependence of λ and T c on the isotopic masses of Mg and B, as revealed from the present work, confirms the role of lattice vibrations in the superconducting behaviour of MgB 2 and the high value of T c in it may be attributed to the phonon mediated e-e interaction coupled with higher values of phonon frequencies due to light mass of B atoms. It has also been observed that the pseudo-atom model (Model-II) with appropriate choice of the potential parameter r c successfully explains high value of T c and isotope effect in MgB 2 , confirming the prominent role played by electron-phonon interaction in the high-T c superconductivity observed in MgB 2 . The isotope effect exponent α-values obtained from the two models are in complete agreement with each other and the present value α = 0.46 is also much closer to the BCS value of 0.5. Interaction strength N 0 V values obtained from the two models are also in perfect agreement with each other and the present value N 0 V = 0.48 suggests that MgB 2 is a strong coupling superconductor. (author)

  20. Sociala Medier som kommunikationskanal för B2B-företag

    OpenAIRE

    Kaddura, Layla; Olsson, Karin

    2010-01-01

    The purpose of this thesis is to show what advantages and opportunities social media offer for B2B-companies (business-to-business), and how they can be used for marketing communications. We have studied how companies can use social media, for example evolving the organization, developing products/services, staying up-to-date, building relations, creating customer loyalty and engagement, building the company’s identity and image, and affecting the buying decisions. We have also studied how B2...

  1. Tau method approximation of the Hubbell rectangular source integral

    International Nuclear Information System (INIS)

    Kalla, S.L.; Khajah, H.G.

    2000-01-01

    The Tau method is applied to obtain expansions, in terms of Chebyshev polynomials, which approximate the Hubbell rectangular source integral:I(a,b)=∫ b 0 (1/(√(1+x 2 )) arctan(a/(√(1+x 2 )))) This integral corresponds to the response of an omni-directional radiation detector situated over a corner of a plane isotropic rectangular source. A discussion of the error in the Tau method approximation follows

  2. Mass Customized Technical Textiles in the B2B Sector

    Science.gov (United States)

    Gebhardt, R.; Barteld, M.; Grafmüller, L.; Mosig, T.; Weiß, M.

    2017-10-01

    Mass Customization is a great opportunity for textile companies for both staying competitive in high-wage countries and offering inexpensive, customized products. Within the area of Technical Textiles, this study focuses on the B2B sector and shows the status quo, potentials and strengths. Both management and technological issues are addressed. For the former, business models and the value co-creation process are dealt with, for the latter, the focus is on modelling.

  3. Customer journey in B2B SaaS business models

    OpenAIRE

    Opanasenko, Mariia

    2017-01-01

    In this paper customer journey for B2B SaaS business models was analyzed to study customer experience, customer success and its key performance indicators. The research method is the case study of Supplier Relationship Management SaaS solution provider. In recent years, the research in customer journey management identified the tendency of acknowledge customer journey as a differentiator and a competitive advantage. Customer journey is a complex process that entails structured customer experi...

  4. Monte Carlo simulation using MCNP4B for an optimal shielding design of a 252 Cf source

    International Nuclear Information System (INIS)

    Silva, Ademir X. da; Crispim, Verginia R.

    2001-01-01

    This study aim to investigate an optimum shielding design against neutrons and gamma-rays from a source of 252 Cf, using Monte Carlo simulation. The shielding materials studied were: borated polyethylene, borated-lead polyethylene and stainless steel. The Monte Carlo code MCNP, version 4B, was used to design shielding for 252 Cf based neutron irradiator systems. By normalizing the dose equivalent rate values presented to the neutron production rate of the source, the resulting calculations are independents of the intensity of actual 252 Cf source. The results shown what the total dose equivalent rates were reduced significantly by the shielding system optimization. (author)

  5. On heavy carbon doping of MgB2

    International Nuclear Information System (INIS)

    Kasinathan, Deepa; Lee, K.-W.; Pickett, W.E.

    2005-01-01

    Heavy carbon doping of MgB 2 is studied by first principles electronic structure studies of two types, an ordered supercell (Mg(B 1-x C x ) 2 , x 0.0833) and also the coherent potential approximation method that incorporates effects of B-C disorder. For the ordered model, the twofold degenerate σ-bands that are the basis of the high temperature superconductivity are split by 60 meV (i.e. 7 meV/% C) and the σ Fermi cylinders contain 0.070 holes/cell, compared to 0.11 for MgB 2 . A virtual crystal treatment tends to overestimate the rate at which σ holes are filled by substitutional carbon. The coherent potential approximation (CPA) calculations give the same rate of band filling as the supercell method. The occupied local density of states of C is almost identical to that of B in the upper 2 eV of the valence bands, but in the range -8 eV to -2 eV, C has a considerably larger density of states. The calculations indicate that the σ Fermi surface cylinders pinch off at the zone center only above the maximum C concentration x ∼ 0.10. These results indicate that Mg(B 1-x C x ) 2 as well as Mg 1-x Al x B 2 is a good system in which to study the evolution of the unusual electron-phonon coupling character and strength as the crucial σ hole states are filled

  6. Potent inhibition of cytochrome P450 2B6 by sibutramine in human liver microsomes.

    Science.gov (United States)

    Bae, Soo Hyeon; Kwon, Min Jo; Choi, Eu Jin; Zheng, Yu Fen; Yoon, Kee Dong; Liu, Kwang-Hyeon; Bae, Soo Kyung

    2013-09-05

    The present study was performed to evaluate the potency and specificity of sibutramine as an inhibitor of the activities of nine human CYP isoforms in liver microsomes. Using a cocktail assay, the effects of sibutramine on specific marker reactions of the nine CYP isoforms were measured in human liver microsomes. Sibutramine showed potent inhibition of CYP2B6-mediated bupropion 6-hydroxylation with an IC50 value of 1.61μM and Ki value of 0.466μM in a competitive manner at microsomal protein concentrations of 0.25mg/ml; this was 3.49-fold more potent than the typical CYP2B6 inhibitor thio-TEPA (Ki=1.59μM). In addition, sibutramine slightly inhibited CYP2C19 activity (Ki=16.6μM, noncompetitive inhibition) and CYP2D6 activity (Ki=15.7μM, noncompetitive inhibition). These observations indicated 35.6- and 33.7-fold decreases in inhibition potency, respectively, compared with that of CYP2B6 by sibutramine. However, no inhibition of CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2D6, or CYP2E1 activities was observed. In addition, the CYP2B6 inhibitory potential of sibutramine was enhanced at a lower microsomal protein concentration of 0.05mg/ml. After 30min preincubation of human liver microsomes with sibutramine in the presence of NADPH, no shift in IC50 was observed in terms of inhibition of the activities of the nine CYPs, suggesting that sibutramine is not a time-dependent inactivator. These observations suggest that sibutramine is a selective and potent inhibitor of CYP2B6 in vitro, whereas inhibition of other CYPs is substantially lower. These in vitro data support the use of sibutramine as a well-known inhibitor of CYP2B6 for routine screening of P450 reversible inhibition when human liver microsomes are used as the enzyme source. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Novel high pressure hexagonal OsB2 by mechanochemistry

    International Nuclear Information System (INIS)

    Xie, Zhilin; Graule, Moritz; Orlovskaya, Nina; Andrew Payzant, E.; Cullen, David A.; Blair, Richard G.

    2014-01-01

    Hexagonal OsB 2 , a theoretically predicted high-pressure phase, has been synthesized for the first time by a mechanochemical method, i.e., high energy ball milling. X-ray diffraction indicated that formation of hexagonal OsB 2 begins after 2.5 h of milling, and the reaction reaches equilibrium after 18 h of milling. Rietveld refinement of the powder data indicated that hexagonal OsB 2 crystallizes in the P63/mmc space group (No. 194) with lattice parameters of a=2.916 Å and c=7.376 Å. Transmission electron microscopy confirmed the appearance of the hexagonal OsB 2 phase after high energy ball milling. in situ X-ray diffraction experiments showed that the phase is stable from −225 °C to 1050 °C. The hexagonal OsB 2 powder was annealed at 1050 °C for 6 days in vacuo to improve crystallinity and remove strain induced during the mechanochemical synthesis. The structure partially converted to the orthorhombic phase (20 wt%) after fast current assisted sintering of hexagonal OsB 2 at 1500 °C for 5 min. Mechanochemical approaches to the synthesis of hard boride materials allow new phases to be produced that cannot be prepared using conventional methods. - Graphical abstract: High resolution transmission electron micrograph of hexagonal OsB 2 nanocrystallite with corresponding fast Fourier transform and simulated diffraction pattern. - Highlights: • Hexagonal OsB 2 has been synthesized for the first time by mechanochemical method. • Hexagonal OsB 2 crystallizes in P63/mmc space group (No. 194), a=2.916 Å and c=7.376 Å. • The hexagonal structure was confirmed by a transmission electron microscope. • No phase transformation was observed after being annealed at 1050 °C for 6 days. • 20 wt% of h-OsB 2 was transformed to o-OsB 2 after being sintered at 1500 °C for 5 min

  8. B physics on the Lattice $\\overline{\\Lambda}$, $\\lambda_{1}$, $\\overline{m}_{b}(\\overline{m}_{b})$, $\\lambda_2$, $B^{0}-\\overline{B}^{0}$ mixing, $f_{B}$ and all that

    CERN Document Server

    Gimenez, V.; Sachrajda, Christopher T.

    1996-01-01

    We present a short review of our most recent high statistics lattice determinations in the HQET of the following important parameters in B physics: the B--meson binding energy, $\\overline{\\Lambda}$ and the kinetic energy of the b quark in the B meson, $\\lambda_1$, which due to the presence of power divergences require a non--perturbative renormalization to be defined; the value in the HQET is determined by the matrix element of the chromo--magnetic operator between B meson states, $\\lambda_2$; the B parameter of the $B^{0}$--$\\bar{B}^{0}$ mixing, $B_{B}$, and the decay constant of the B meson, $f_{B}$. All these quantities have been computed using a sample of $600$ gauge field configurations on a $24^{3}\\times 40$ lattice at $\\beta=6.0$. For estimates by combining results from three independent lattice simulations at

  9. Stronger enhancer II/core promoter activities of hepatitis B virus isolates of B2 subgenotype than those of C2 subgenotype.

    Science.gov (United States)

    Qin, Yanli; Zhou, Xueshi; Jia, Haodi; Chen, Chaoyang; Zhao, Weifeng; Zhang, Jiming; Tong, Shuping

    2016-07-27

    Hepatitis B virus (HBV) genotype C causes prolonged chronic infection and increased risk for liver cancer than genotype B. Our previous work revealed lower replication capacity of wild-type genotype C2 than B2 isolates. HBV DNA replication is driven by pregenomic RNA, which is controlled by core promoter (CP) and further augmented by enhancer I (ENI) and enhancer II (ENII). DNA fragments covering these regulatory elements were amplified from B2 and C2 isolates to generate luciferase reporter constructs. As ENII is fully embedded in CP, we inserted HBV DNA fragments in the sense orientation to determine their combined activities, and in the antisense orientation to measure enhancer activities alone. Genotype B2 isolates displayed higher ENI+ENII+CP, ENII+CP, and ENII activities, but not ENI or ENI+ENII activity, than C2 isolates. The higher ENII+CP activity was partly attributable to 4 positions displaying genotype-specific variability. Exchanging CP region was sufficient to revert the replication phenotypes of several B2 and C2 clones tested. These results suggest that a weaker ENII and/or CP at least partly accounts for the lower replication capacities of wild-type C2 isolates, which could drive the subsequent acquisition of CP mutations. Such mutations increase genome replication and are implicated in liver cancer development.

  10. Implementation and evaluation of PM2.5 source contribution ...

    Science.gov (United States)

    Source culpability assessments are useful for developing effective emissions control programs. The Integrated Source Apportionment Method (ISAM) has been implemented in the Community Multiscale Air Quality (CMAQ) model to track contributions from source groups and regions to ambient levels and deposited amounts of primary and secondary inorganic PM2.5. Confidence in this approach is established by comparing ISAM source contribution estimates to emissions zero-out simulations recognizing that these approaches are not always expected to provide the same answer. The comparisons are expected to be most similar for more linear processes such as those involving primary emissions of PM2.5 and most different for non-linear systems like ammonium nitrate formation. Primarily emitted PM2.5 (e.g. elemental carbon), sulfur dioxide, ammonia, and nitrogen oxide contribution estimates compare well to zero-out estimates for ambient concentration and deposition. PM2.5 sulfate ion relationships are strong, but nonlinearity is evident and shown to be related to aqueous phase oxidation reactions in the host model. ISAM and zero-out contribution estimates are less strongly related for PM2.5 ammonium nitrate, resulting from instances of non-linear chemistry and negative responses (increases in PM2.5 due to decreases in emissions). ISAM is demonstrated in the context of an annual simulation tracking well characterized emissions source sectors and boundary conditions shows source contri

  11. B2B-verkkokaupan kehittäminen vaatetusalan pienyritykselle

    OpenAIRE

    Sivonen, Maisa

    2016-01-01

    Opinnäytetyö kertoo erään suomalaisen vaatetusalan yrityksen B2B-verkkokaupan kehittämisestä kaupallisemmaksi, käyttäjäystävällisemmäksi ja kohderyhmälähtöisemmäksi. Työ toteutettiin toimeksiantona suomalaiselle miesten vapaa-ajan vaatteisiin erikoistuneelle pienyritykselle keväällä 2016. Toimeksiannon lähtökohtana toimi yhteistyöyrityksen aito tarve kehittää jo olemassa olevaa yritysverkkokauppaansa palvelemaan paremmin asiakkaidensa tarpeita ja tätä kautta parantaa sähköistä yritysmyyn...

  12. Neutron diffraction studies of magnetic ordering in superconducting ErNi2B2C and TmNi2B2C in an applied magnetic field

    DEFF Research Database (Denmark)

    Toft, Katrine Nørgaard

    The field-induced magnetic structures of ErNi2B2C and TmNi2B2C in are especially interesting because the field suppresses the superconducting order parameter and therefore the magnetic properties can be studied while varying the strength ofsuperconductivity. ErNi2B2C: For magnetic fields along all.......483,0,0). The appearance of the QN phase wasinitially 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 QN.The phase diagram...... 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 (QNB = (0,Q...

  13. MgB sub 2 superconductor: a review

    CERN Document Server

    Mollah, S; Chaudhuri, B K

    2003-01-01

    Synthesis, structure and properties of the most intensively studied newly discovered intermetallic binary superconductor MgB sub 2 have been reviewed up to October, 2002. It has a hexagonal unit cell with cell parameters a approx 3.1432 A and c approx 3.5193 A. MgB sub 2 bulk samples synthesized under high pressure (approx 3.5 GPa) and high temperature (approx 1000 degC) has density approx 2.63 g/cm sup 3. The normal state carriers of MgB sub 2 are holes which have been established from the positive thermoelectric power and Hall coefficient measurements. The external pressure decreases the critical temperature (T sub c) with dT sub c /dP in the range of -1 to -2 K/GPa. The T sub c decreases rapidly by the doping of Mn, Li, Co, C, Al, Ni and Fe but increases slightly by Zn doping. However, no significant change of T sub c is observed by the doping of Si and Be. It is further noticed that the anisotropic ratio gamma(= H sub c sub 2 sup a sup b /H sub c sub 2 sup c) approx 1-5 with lower critical field (H sub c ...

  14. The CVD ZrB2 as a selective solar absorber

    Science.gov (United States)

    Randich, E.; Allred, D. D.

    Coatings of ZrB2 and TiB2 for photothermal solar absorber applications were prepared using chemical vapor deposition (CVD) techniques. Oxidation tests suggest a maximum temperature limit for air exposure of 600 K for TiB2 and 800 K for Z4B2. Both materials exhibit innate spectral selectivity with emittance at 375 K ranging from 0.06 to 0.09 and solar absorptance for ZrB2 ranging from 0.67 to 0.77 and solar absorptance for TiB2 ranging from 0.46 to 0.58. ZrB2 has better solar selectivity and more desirable oxidation behavior than TiB2. A 0.071 micrometer antireflection coating of Si3N4 deposited on the ZrB2 coating leads to an increase in absorptance from 0.77 to 0.93, while the emittance remains unchanged.

  15. Photoluminescence in Pb{sup 2+} activated SrB{sub 4}O{sub 7} and SrB{sub 2}O{sub 4} phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Gawande, A.B., E-mail: gawandeab@gmail.com [Department of Physics, SGB Amravati University, Amravati-444602, Maharashtra (India); Ingle, J.T. [J. D. Institute of Engineering and Technology, Yavatmal, Maharashtra (India); Sonekar, R.P., E-mail: sonekar_rp@yahoo.com [Department of Physics, G.S. College, Khamgaon District, Buldhana, Maharashtra (India); Omanwar, S.K. [Department of Physics, SGB Amravati University, Amravati-444602, Maharashtra (India)

    2014-05-01

    The powder samples of SrB{sub 4}O{sub 7}:Pb{sup 2+} and SrB{sub 2}O{sub 4}:Pb{sup 2+} were prepared by solution combustion synthesis method. The synthesis is based on the exothermic reaction between the fuel (Urea) and Oxidizer (Ammonium nitrate). The synthesized materials were characterized using TG–DTA, powder XRD, SEM and the photoluminescence properties were studied using a Hitachi F-7000 spectrophotometer at room temperature. Both the samples SrB{sub 4}O{sub 7}:Pb{sup 2+} and SrB{sub 2}O{sub 4}:Pb{sup 2+} show broad emission of Pb{sup 2+} respectively at 307 nm and 360 nm (corresponds to {sup 3}P{sub 1} to {sup 1}S{sub 0} transition). The optimum concentrations of Pb{sup 2+} in both the phosphors SrB{sub 4}O{sub 7}:Pb{sup 2+} and SrB{sub 2}O{sub 4}:Pb{sup 2+} were found to be 3 mol% (relative to Sr) and for this concentration the critical transfer distance R{sub 0} were calculated to be 10.21 Å and 12.22 Å respectively. The Stokes shifts were calculated to be respectively 4464 cm{sup −1} and 8454 cm{sup −1}. The emission bands of both the phosphors are in the UV region and the phosphors can be potential candidates for application in UV lamps. - Highlights: • SrB{sub 4}O{sub 7}:Pb{sup 2+} and SrB{sub 2}O{sub 4}:Pb{sup 2+} have been synthesized by Novel solution combustion synthesis technique. • The synthesized materials were characterized using TG–DTA, powder XRD and SEM. • Photoluminescence spectra of synthesized materials showed the characteristic transition in Pb{sup 2+}. • Stokes shift, optimum concentration and critical transfer distance R{sub 0} were determined.

  16. The conserved nhaAR operon is drastically divergent between B2 and non-B2 Escherichia coli and is involved in extra-intestinal virulence.

    Science.gov (United States)

    Lescat, Mathilde; Reibel, Florence; Pintard, Coralie; Dion, Sara; Glodt, Jérémy; Gateau, Cecile; Launay, Adrien; Ledda, Alice; Cruveiller, Stephane; Cruvellier, Stephane; Tourret, Jérôme; Tenaillon, Olivier

    2014-01-01

    The Escherichia coli species is divided in phylogenetic groups that differ in their virulence and commensal distribution. Strains belonging to the B2 group are involved in extra-intestinal pathologies but also appear to be more prevalent as commensals among human occidental populations. To investigate the genetic specificities of B2 sub-group, we used 128 sequenced genomes and identified genes of the core genome that showed marked difference between B2 and non-B2 genomes. We focused on the gene and its surrounding region with the strongest divergence between B2 and non-B2, the antiporter gene nhaA. This gene is part of the nhaAR operon, which is in the core genome but flanked by mobile regions, and is involved in growth at high pH and high sodium concentrations. Consistently, we found that a panel of non-B2 strains grew faster than B2 at high pH and high sodium concentrations. However, we could not identify differences in expression of the nhaAR operon using fluorescence reporter plasmids. Furthermore, the operon deletion had no differential impact between B2 and non-B2 strains, and did not result in a fitness modification in a murine model of gut colonization. Nevertheless, sequence analysis and experiments in a murine model of septicemia revealed that recombination in nhaA among B2 strains was observed in strains with low virulence. Finally, nhaA and nhaAR operon deletions drastically decreased virulence in one B2 strain. This effect of nhaAR deletion appeared to be stronger than deletion of all pathogenicity islands. Thus, a population genetic approach allowed us to identify an operon in the core genome without strong effect in commensalism but with an important role in extra-intestinal virulence, a landmark of the B2 strains.

  17. Design parameters and source terms: Volume 2, Source terms: Revision 0

    International Nuclear Information System (INIS)

    1987-09-01

    The Design Parameters and Source Terms Document was prepared in accordance with DOE request and to provide data for the environmental impact study to be performed in the future for the Deaf Smith County, Texas site for a nuclear waste repository in salt. This document updates a previous unpublished report to the level of the Site Characterization Plan---Conceptual Design Report SCP-CDR. The previous study identifies the data needs for the Environmental Assessment effort for seven possible salt repository sites. Volume 2 contains tables of source terms

  18. Study of the CdX-B2X3-X (X=S, Se), CdTe-B-Te systems

    International Nuclear Information System (INIS)

    Odin, I.N.; Grin'ko, V.V.; Safronov, E.V.; Kozlovskij, V.F.

    2001-01-01

    Liquidus surfaces of the CdX-B 2 X 3 -X (X=S, Se), CdTe-B-Te systems are plotted for the first time. It is shown that in equilibrium solid solutions on the basis of ternary Cd 2 B 2 X 5 compounds and binary B 2 X 3 , CdX, BS 2 compounds take part with liquid phases. p gen -T and T-x projects of p-T-x phase diagram of B-S (59-100 at. % S), B-Se (59-100 at. % Se), B-Te systems are plotted . B 2 X 3 , BS 2 compounds are formed in that regions of compositions of B-X systems . In the B-Te system compounds are not formed. Ternary compounds are not formed in the CdTe-B-Te system [ru

  19. Software-Lösungen in B2B-Verkaufsgesprächen wirkungsvoll einsetzen

    OpenAIRE

    Thoma, Axel Michael

    2017-01-01

    Dieser Beitrag befasst sich mit dem Einsatz von Software-Lösungen in B2B-Verkaufsgesprächen (auf Englisch: Digital Sales Enablement). Anhand aktueller Beispiele aus der Geschäftswelt wird erklärt, wie solche Lösungen helfen (1) die Produktivität zu steigern, (2) Kunden zu aktivieren und (3) Neugeschäft zu entwickeln. Ebenfalls werden die Konzeption und Umsetzung solcher Lösungen behandelt.

  20. Production of Al-Ti-B grain refining master alloys from Na2B4O7 and K2TiF6

    International Nuclear Information System (INIS)

    Birol, Yuecel

    2008-01-01

    It is very desirable to replace the KBF 4 salt in the popular 'halide salt' process to reduce the volume of fluoride salts to be added to molten aluminium in the production of Al-Ti-B grain refiners. Being over 2 times richer in B, Na 2 B 4 O 7 is a promising replacement for KBF 4 , and is used in the present work to produce Al-Ti-B grain refiner master alloys. A fraction of the aluminide particles were entrapped in the spent salt giving a relatively lower Ti recovery when KBF 4 was replaced by Na 2 B 4 O 7 . The grain refining performance of the Al-Ti-B grain refiner alloy thus produced was nevertheless acceptable. The spent salt became too viscous with the oxides, aluminides and borides to be removed by decanting when Na 2 B 4 O 7 .5H 2 O was used to supply boron. The viscous spent salt, entrained in the grain refiner alloy, did not only impair its performance, but also hurt the fluidity of the molten alloy and made pouring difficult

  1. Lattice Thermal Conductivity of Ultra High Temperature Ceramics ZrB2 and HfB2 from Atomistic Simulations

    Science.gov (United States)

    Lawson, John W.; Murray, Daw S.; Bauschlicher, Charles W., Jr.

    2011-01-01

    Atomistic Green-Kubo simulations are performed to evaluate the lattice thermal conductivity for single crystals of the ultra high temperature ceramics ZrB2 and HfB2 for a range of temperatures. Recently developed interatomic potentials are used for these simulations. Heat current correlation functions show rapid oscillations which can be identified with mixed metal-Boron optical phonon modes. Agreement with available experimental data is good.

  2. 17 CFR 270.8b-2 - Definitions.

    Science.gov (United States)

    2010-04-01

    ... such document is filed with such exchange. (j) Share. The term “share” means a share of stock in a... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Definitions. 270.8b-2 Section 270.8b-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND...

  3. Evaluation of FlaB1, FlaB2, FlaB3, and Tp0463 of Treponema pallidum for serodiagnosis of syphilis.

    Science.gov (United States)

    Jiang, Chuanhao; Xiao, Jinhong; Xie, Yafeng; Xiao, Yongjian; Wang, Chuan; Kuang, Xingxing; Xu, Man; Li, Ranhui; Zeng, Tiebing; Liu, Shuanquan; Yu, Jian; Zhao, Feijun; Wu, Yimou

    2016-02-01

    Syphilis is a multistage disease caused by the invasive spirochete Treponema pallidum subsp. pallidum, and accurate diagnosis is important for the prevention and treatment of syphilis. Here, to identify appropriate diagnostic antigens for serodiagnosis of syphilis, 6 recombinant proteins were expressed in Escherichia coli and purified, including flagellins (FlaB1 [Tp0868], FlaB2 [Tp0792], and FlaB3 [Tp0870]), Tp0463, Tp0751, and Tp1038. The sensitivities were determined by screening sera from individuals with primary (n=82), secondary (n=115), latent (n=105), and congenital (n=65) syphilis. The specificities were determined by screening sera from uninfected controls (n=30) and potentially cross-reactive infections including Lyme disease (n=30), leptospirosis (n=5), and hepatitis B (n=30). Our data showed that FlaB1, FlaB2, FlaB3, Tp0463, and Tp1038 exhibited higher overall sensitivities and specificities for detecting IgG antibody, with 95.4% and 98.9%, 92.6% and 95.8%, 95.1% and 95.8%, 92.6% and 97.9%, and 95.9% and 98.9%, respectively. In contrast, Tp0751 demonstrated only an overall sensitivity of 39.2%. For comparison, the sensitivity and specificity of Architect Syphilis TP were determined to be 98.1% and 93.7%, respectively. In addition, FlaB1, FlaB2, FlaB3, and Tp0463 demonstrated excellent performance for detecting IgM antibody in primary and congenital syphilis, with sensitivities of 76.8% and 83.1%, 72.0% and 87.7%, 74.4% and 89.2%, and 64.6% and 75.3%, respectively. These results indicate that FlaB1, FlaB2, FlaB3, and Tp0463 could be as novel diagnostic candidates for serodiagnosis of syphilis. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Synthesis and structure of PbBipy2(1-B10H9S(CH3)2)2

    International Nuclear Information System (INIS)

    Orlova, A.M.; Sivaev, I.B.; Lagun, V.L.; Katser, S.B.; Solntsev, K.A.; Kuznetsov, N.T.

    1993-01-01

    Lead complex with B 10 H 9 S(CH 3 ) 2 - anion and 2,2'-bipyridine was synthesized and characterized. According to the data of X-ray diffraction analysis the crystals belong to monoclinic crystal system, sp. gr. P2 1 /a: a = 9.940(4), b 31.568(4), c = 13.458(2) A, β = 111.09(2) deg, V = 3940(2) A 3 , Z = 4. The structure consists of monomer units PbBipy 2 (1-B 10 H 9 S(CH 3 ) 2 ) 2 . The Pb-B distances are within 3.24-3.55 A. 15 refs., 1 fig., 2 tabs

  5. OS2_OSCAT_LEVEL_2B_OWV_COMP_12_V2:1

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset consists of the version 2 Level 2B science-quality ocean surface wind vector retrievals from the Oceansat-2 scatterometer (OSCAT), which was designed...

  6. First principle study of UHTC ternary diboride, Cr2AlB2

    Science.gov (United States)

    Rastogi, Anugya; Rajpoot, Priyanka; Verma, U. P.

    2018-04-01

    In this paper ab-initio study of the structural, electronic and optical properties of ternary metal boride Cr2AlB2 using full potential linear augmented plane wave (FP-LAPW) method based on the density functional theory (DFT). The study of structural properties shows that Cr2AlB2 is metallic in nature and have orthorhombic crystal structure. The optical properties show that it possess anisotropic behavior, which have wide applications in electricity production through concentration of solar power (CSP) technology. To the best of our knowledge, theoretical study of the optical properties of Cr2AlB2 is reported for the first time.

  7. Magnetic phase diagram of ErNi2B2C

    DEFF Research Database (Denmark)

    Jensen, A.; Toft, K.N.; Abrahamsen, A.B.

    2004-01-01

    The magnetic phase diagram of the superconductor ErNi2B2C (T-c = 11 K and T-N = 6 K) has been studied by neutron diffraction as a function of temperature and magnetic field applied along the symmetry directions [010], [110] and [001] of the tetragonal crystal structure. A series of commensurate...... magnetic structures, consistent with a transversely polarized spin-density wave with modulation vectors Q = n/ma* (0.55 less than or equal to n/m field model that has been established from...... an analysis of bulk magnetization and zero-field neutron diffraction data. The model accounts for most of the observed features but fails to explain the occurrence of a small component Qdelta approximate to -0.005b* observed close to H-c2 when the field is applied along [110]. (C) 2004 Elsevier B.V. All...

  8. Data of evolutionary structure change: 2QU0A-2DN1B [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available >A 2QU0A WGKVGGNAGAYGence> HHHH...2QU0A-2DN1B 2QU0 2DN1 A B VLSAADKSNVKAAWGKVGGNAGAYGAEALERMFLSFPTT...index>0 2DN1 B 2DN1B ...ence>WGKVN--VDEVGence> GGG --HHHHH VAL CA 367 GLY CA 400 2QU0

  9. CO2 Sink/Source in the Indonesian Seas

    KAUST Repository

    Kartadikaria, Aditya R.

    2015-04-01

    Two distinct CO2 sink/source characteristics appeared from the compiled observed data 1984-2013 in the tropical Indonesian seas. The western part persistently emits CO2 to the atmosphere, while the eastern is rather dynamic which emits and absorbs smaller amount of CO2 to and from atmosphere, respectively. The segregation is proximal to the virtual Wallace line, where in the continental shelf is located. Lower salinity and higher silicate condition in the western part influenced the higher pCO2 condition in Java Sea. Temperature is found to have a limited influence to control different characteristic in the west and east, but SST change of 2.0 0C during La Ninã condition effectively reduced the source amount of CO2 by 50% compared to Normal year condition. Yet, during La Ninã, higher wind speed increases CO2 flux twice compared to Normal year. In the continental shelf area where CO2 sink area is found, 29 years data showed that pCO2 trend is increasing ±0.6-3.8 μatm/year. From this study, the overall areas have a significant source of CO2 of approximately 10 - 24 μatm.

  10. A complex relationship between TRAF3 and non-canonical NF-κB2 activation in B lymphocytes

    Directory of Open Access Journals (Sweden)

    Wai Wai Lin

    2013-12-01

    Full Text Available The adaptor protein TRAF3 restrains BAFF receptor (BAFFR and CD40-mediated activation of the NF-κB2 pathway in B cells. Mice lacking TRAF3 specifically in B cells revealed the critical role of TRAF3 in restraining homeostatic B cell survival. Furthermore, loss- of-function mutations of the traf3 gene have been associated with human B cell malignancies, especially multiple myeloma (MM. It has been proposed that receptor-induced TRAF3 degradation leads to stabilization of the NF-B inducing kinase NIK, and subsequent NF-κB2 activation. However, it is unclear how receptor-mediated TRAF3 degradation or loss of function contributes to B cell-specific NF-κB2 activation. In the current study, we employed two complementary models to address this question. One utilized a mutant traf3 gene found in a human MM-derived cell line called LP1. The LP1 mutant TRAF3 protein lacks the TRAF-N and TRAF-C domains. Consistent with the paradigm described, expression of LP1 TRAF3 in B cells promoted higher basal levels of NF-κB2 activation compared to Wt TRAF3. However, LP1 did not associate with TRAF2, CD40, or BAFFR, and no LP1 degradation was observed following receptor engagement. Interestingly, LP1 showed enhanced NIK association. Thus, TRAF3 degradation becomes dispensable to activate NF-κB2 when it is unable to associate with TRAF2. In a second model, we examined several mutant forms of BAFFR that are unable to induce NF-κB2 activation in B cells. Signaling to B cells by each of these BAFFR mutants, however, induced levels of TRAF3 degradation similar to those induced by Wt BAFFR. Thus, in B cells, receptor-mediated TRAF3 degradation is not sufficient to promote NF-B2 activation. We thus conclude that there is not a simple linear relationship in B lymphocytes between relative levels of cellular TRAF3, induced TRAF3 degradation, NIK activation and NF-B2 activation.

  11. Nonlinear Elasticity of Borocarbide Superconductor YNi2B2C: A First-Principles Study

    Directory of Open Access Journals (Sweden)

    Lili Liu

    2017-01-01

    Full Text Available First-principles calculations combined with homogeneous deformation methods are used to investigate the second- and third-order elastic constants of YNi2B2C with tetragonal structure. The predicted lattice constants and second-order elastic constants of YNi2B2C agree well with the available data. The effective second-order elastic constants are obtained from the second- and third-order elastic constants for YNi2B2C. Based on the effective second-order elastic constants, Pugh’s modulus ratio, Poisson’s ratio, and Vickers hardness of YNi2B2C under high pressure are further investigated. It is shown that the ductility of YNi2B2C increases with increasing pressure.

  12. Trapped magnetic field in a (NdFeB)–(MgB2) pair-type bulk magnet

    International Nuclear Information System (INIS)

    Aldica, Gheorghe; Burdusel, Mihail; Badica, Petre

    2014-01-01

    Highlights: • Dense MgB 2 discs were obtained by ex-situ Spark Plasma Sintering. • A NdFeB–MgB 2 pair-type bulk magnet was tested for different working conditions. • The polarity of the NdFeB permanent magnet influences macro flux jumps of MgB 2 . • Trapped field of the pair was 2.45 T (20 K) and 3.3 T (12 K). - Abstract: Superconducting bulk discs, S, of 20 mm in diameter and 3.5 or 3.3 mm thickness of MgB 2 (pristine or added with cubic BN, respectively) with density above 97% were prepared by Spark Plasma Sintering. Discs were combined in a pair-type sandwich-like arrangement with a permanent NdFeB axially magnetised magnet, PM (∼0.5 T). Measurement of the trapped field, B tr , with temperature, time, and the reduction rate of the applied magnetic field was performed using a Hall sensor positioned at the centre between the superconductor and the permanent magnet. It is shown that the permanent magnet with certain polarity favors higher trapped field of the superconductor owing to suppression of flux jumps specific for high density MgB 2 samples. The B tr of the PM–S pair was 2.45 T (20 K) and 3.3 T (12 K)

  13. Performance evaluation of wideband bio-impedance spectroscopy using constant voltage source and constant current source

    International Nuclear Information System (INIS)

    Mohamadou, Youssoufa; Oh, Tong In; Wi, Hun; Sohal, Harsh; Farooq, Adnan; Woo, Eung Je; McEwan, Alistair Lee

    2012-01-01

    Current sources are widely used in bio-impedance spectroscopy (BIS) measurement systems to maximize current injection for increased signal to noise while keeping within medical safety specifications. High-performance current sources based on the Howland current pump with optimized impedance converters are able to minimize stray capacitance of the cables and setup. This approach is limited at high frequencies primarily due to the deteriorated output impedance of the constant current source when situated in a real measurement system. For this reason, voltage sources have been suggested, but they require a current sensing resistor, and the SNR reduces at low impedance loads due to the lower current required to maintain constant voltage. In this paper, we compare the performance of a current source-based BIS and a voltage source-based BIS, which use common components. The current source BIS is based on a Howland current pump and generalized impedance converters to maintain a high output impedance of more than 1 MΩ at 2 MHz. The voltage source BIS is based on voltage division between an internal current sensing resistor (R s ) and an external sample. To maintain high SNR, R s is varied so that the source voltage is divided more or less equally. In order to calibrate the systems, we measured the transfer function of the BIS systems with several known resistor and capacitor loads. From this we may estimate the resistance and capacitance of biological tissues using the least-squares method to minimize error between the measured transimpedance excluding the system transfer function and that from an impedance model. When tested on realistic loads including discrete resistors and capacitors, and saline and agar phantoms, the voltage source-based BIS system had a wider bandwidth of 10 Hz to 2.2 MHz with less than 1% deviation from the expected spectra compared to more than 10% with the current source. The voltage source also showed an SNR of at least 60 dB up to 2.2 MHz

  14. Dry cryomagnetic system with MgB2 coil

    Science.gov (United States)

    Abin, D. A.; Mineev, N. A.; Osipov, M. A.; Pokrovskii, S. V.; Rudnev, I. A.

    2017-12-01

    MgB2 may be the future superconducting wire material for industrial magnets due to it’s higher operation temperature and potentially lower cost than low temperature superconductors (LTS) have. We designed a compact cryomagnetic system with the use of MgB2. The possibility of creating a magnet with a central field of 5 T from a commercial MgB2 wire by the “react and wound” method was investigated. The magnetic system is cooled by a cryocooler through a copper bus. The magnet has a warm bore diameter of 4 cm. The design of a magnet consisting of three concentric solenoids is proposed: an internal one of high-temperature superconductor (HTS), an average of MgB2, and an external of NbTi. The operating current of the system is 100 A. Two pairs of current leads are used. A separate pair of current leads for power supplying NbTi coil allows testing of MgB2 and HTS coils in an external field. The load curves for each of the magnets are calculated.

  15. Formation and early hydration characteristics of C2.75B1.25A3$ in binary system of C2.75B1.25A3$-C2S

    Directory of Open Access Journals (Sweden)

    Wang, Shoude

    2016-09-01

    Full Text Available C2.75B1.25A3$ (2.75CaO•1.25BaO• 3Al2O3• SO3 is one of the important minerals and it govern-directly the early-strength of belite-barium calcium sulphoaluminate cement. In this paper a binary system C2.75B1.25A3$-C2S is selected to investigate the formation of C2.75B1.25A3$. In the range of 1100 °C–1200 °C, the earlier formed C2S hinders the formation of C2.75B1.25A3$. On the contrary, when the temperature is in the range of 1200 °C–1350 °C, the initially formed C2S could provide a surface for the nucleation of C2.75B1.25A3$ and cut down the potential barrier (?Gk* for the heterogeneous nucleation of C2.75B1.25A3$, which contributes to its formation. Moreover, at 1350 °C, the large amount of previously formed C2S benefits the extent of formation of C2.75B1.25A3$. The possible reason was that it could prevent sulfur evaporation. In early hydration age, AFm and AFt originating from C2.75B1.25A3$ hydration are found within 2 h and 12 h under 95% RH at 1 °C, respectively, whereas C2S is unhydrated at this moment.En el cemento de sulfoaluminato de calcio y bario, el C2.75B1.25A3$ (2.75CaO•1.25BaO• 3Al2 O3• SO3 es una de las principales fases, y regula directamente la resistencia inicial del cemento. En este trabajo, se ha seleccionado el sistema binario C2.75B1.25A3$-C2S para investigar la formación de C2.75B1.25A3$. En el rango de 1100 °C-1200 °C, el C2S formado anteriormente impide la formación de C2.75B1.25A3$, mientras que cuando la temperatura está entre 1200 °C-1350 °C, el C2S proporcionaría una superficie de nucleación de C2.75B1.25A3$ reduciendo la barrera de potencial (?Gk* para la nucleación heterogénea de C2.75B1.25A3$, lo que contribuye a su formación. Además, a 1350 °C, la gran cantidad de C2S formado beneficia la formación de C2.75B1.25A3$, ya que podía prevenir la evaporación del azufre. En las primeras etapas de la hidratación (entre 2 y 12h y 95% HR a 1 ºC se pueden encontrar AFM y AFt

  16. Vitamin B2 content determination in liver paste by using acid and acid-enzyme hydrolysis

    Directory of Open Access Journals (Sweden)

    Basić Zorica

    2007-01-01

    the samples (r = 0.9994, and r = 0.99987. Hydrolysis procedures make a sample suitable for vitamin B2 determination. In the liver paste samples a high content of vitamin B2 was determined: 0.83 mg/100 g after acid hydrolysis, and 0.909 mg/100 g after acid-enzyme hydrolysis. There were statistically significantly higher values determined after the acid-enzyme hydrolysis (p < 0.05. Conclusion. Using acid-enzyme hydrolysis and separation instrument technique (liquid chromatography with a fluorescent detector as detection system, statistically significantly greater vitamin B2 quantities were determined than after using acid hydrolysis procedure. Vitamin B2 content determined in ten liver paste samples was high (0.881 − 0.936 mg/100g indicating that this meat product is a good vitamin B2 source.

  17. Ni-ZrB2 electrocomposites

    International Nuclear Information System (INIS)

    Pushpavanam, M.; Natarajan, S.R.

    1992-01-01

    New generation materials require high temperature oxidation resistance besides many other tribological properties. Ni-ZrB 2 composites and their properties are dealt with in this paper. (author). 7 refs., 3 figs., 4 tabs

  18. EBI2 overexpression in mice leads to B1 B cell expansion and chronic lymphocytic leukemia-(CLL)-like B cell malignancies

    DEFF Research Database (Denmark)

    Niss Arfelt, Kristine; Barington, Line; Benned-Jensen, Tau

    2017-01-01

    -targeted expression of human EBI2 in mice reduces germinal center-dependent immune responses, reduces total IgM and IgG levels, and leads to increased proliferation and upregulation of cellular oncogenes. Furthermore, hEBI2 overexpression leads to an abnormally expanded CD5+ B1a B cell subset present as early as 4......Human and mouse chronic lymphocytic leukemia (CLL) develop from CD5+ B cells that in mice and macaques are known to define the distinct B1a B cell lineage. B1a cells are characterized by lack of germinal center development and the B1a cell population is increased in mice with reduced germinal...... cells towards the extrafollicular area, whereas downregulation is essential for germinal center formation. We therefore speculated whether increased expression of EBI2 would lead to an expanded B1 cell subset and, ultimately, progression to chronic lymphocytic leukemia. Here we demonstrate that B cell...

  19. Occurrence of Ochratoxins, Fumonisin B2 , Aflatoxins (B1 and B2 ), and Other Secondary Fungal Metabolites in Dried Date Palm Fruits from Egypt: A Mini-Survey.

    Science.gov (United States)

    Abdallah, Mohamed F; Krska, Rudolf; Sulyok, Michael

    2018-02-01

    This study was conducted to investigate the natural co-occurrence of 295 fungal and bacterial metabolites in 28 samples of dried date palm fruits collected from different shops distributed in Assiut Governorate, Upper Egypt in 2016. Extraction and quantification of the target analytes were done using the "dilute and shoot" approach followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. In total, 30 toxic fungal metabolites were detected. Among these metabolites, 4 types of ochratoxins including ochratoxin type A and B were quantified in 3 samples (11%) with a contamination range from 1.48 to 6070 μg/kg for ochratoxin A and from 0.28 to 692 μg/kg for ochratoxin B. In addition, fumonisin B 2 was observed in 2 (7%) samples with contamination levels ranging from 4.99 to 16.2 μg/kg. The simultaneous detection of fumonisin B 2 in the same contaminated samples with ochratoxins indicates the fungal attack by Aspergillus niger species during storage. Only 1 sample was contaminated with aflatoxin B 1 (14.4 μg/kg) and B 2 (2.44 μg/kg). The highest maximum concentration (90400 μg/kg) was for kojic acid that contaminated 43% of the samples. To the best of the authors' knowledge, this is the first report of the natural co-occurrence of fumonisin B 2 and ochratoxin A and B in addition to a wide range of other fungal metabolites in date palm fruits. Mycotoxins are secondary metabolites produced by different fungi. These metabolites pose a potential risk on human health since they contaminate many food commodities. Among these, date palm fruits which are an integral part of diet in several countries. Therefore, detection of mycotoxins is a prerequisite to insure the safety of food. Here, different types of mycotoxins have been detected in levels that may have health hazard. © 2018 Institute of Food Technologists®.

  20. Design parameters and source terms: Volume 2, Source terms: Revision 0

    International Nuclear Information System (INIS)

    1987-10-01

    The Design Parameters and Source Terms Document was prepared in accordance with DOE request and to provide data for the environmental impact study to be performed in the future for the Deaf Smith County, Texas site for a nuclear waste repository in salt. This document updates a previous unpublished report by Stearns Catalytic Corporation (SCC), entitled ''Design Parameters and Source Terms for a Two-Phase Repository Salt,'' 1985, to the level of the Site Characterization Plan - Conceptual Design Report. The previous unpublished SCC Study identifies the data needs for the Environmental Assessment effort for seven possible Salt Repository sites. 2 tabs

  1. Ion Source Physics and Technology (2/2)

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    This series of lectures starts with an introduction in some aspects of atomic and plasma physics as base for the ion source physics. The main part covers aspects of ion source physics, technology and operation. Several source types are presented. Some information on infrastructure and supporting services (as high voltage, cooling, microwaves etc) are given to better understand the source environment. The last part on engineering aims to show that, in the field of ion sources, many different technologies are combined in a quite small environment, which is challenging and interesting at the same time.

  2. Impurity radiation from a beam-plasma neutron source

    International Nuclear Information System (INIS)

    Molvik, A.W.

    1995-01-01

    Impurity radiation, in a worst case evaluation for a beam-plasma neutron source (BPNS), does not limit performance. Impurities originate from four sources: (a) sputtering from walls by charge exchange or alpha particle bombardment, (b) sputtering from limiters, (c) plasma desorption of gas from walls and (d) injection with neutral beams. Sources (c) and (d) are negligible; adsorbed gas on the walls of the confinement chamber and the neutral beam sources is removed by the steady state discharge. Source (b) is negligible for impinging ion energies below the sputtering threshold (T i ≤ 0.025 keV on tungsten) and for power densities to the limiter within the capabilities of water cooling (30-40 MW/m 2 ); both conditions can be satisfied in the BPNS. Source (a) radiates 0.025 MW/m 2 to the neutron irradiation samples, compared with 5 to 10 MW/m 2 of neutrons; and radiates a total of 0.08 MW from the plasma column, compared with 60 MW of injected power. The particle bombardment that yields source (a) deposits an average of 2.7 MW/m 2 on the samples, within the capabilities of helium gas cooling (10 MW/m 2 ). An additional worst case for source (d) is evaluated for present day 2 to 5 s pulsed neutral beams with 0.1% impurity density and is benchmarked against 2XIIB. The total radiation would increase a factor of 1.5 to ≤ 0.12 MW, supporting the conclusion that impurities will not have a significant impact on a BPN. (author). 61 refs, 7 figs, 2 tabs

  3. Tribology study on TiB2+WSi2 composite against WC

    Science.gov (United States)

    Murthy, T. S. R. Ch.; Basha, M. M.; Sonber, J. K.; Singh, K.; Raju, K.; Sairam, K.; Nagaraj, A.; Majumdar, S.; Rao, G. V. S. Nageswara; Kain, Vivekanand

    2018-04-01

    Titanium diboride (TiB2) is one of the potential material for green energy applications such as neutron absorber in high temperature/advanced nuclear reactors, receiver materials for second generation concentrated solar power. We developed the process flow sheet for synthesis and consolidation of various series of TiB2 based materials in our laboratory. Amongst these, TiB2+WSi2 exhibited better sinterability and oxidation resistance properties. In the present work, tribology properties of TiB2+2.5%WSi2 composite was studied against WC-Co ball using different normal loads (5, 10 and 20 N) and frequencies (10, 15 Hz) under dry condition. Coefficient of friction (COF) and wear rate was measured at all test conditions. Wear mechanism was analyzed by microstructural characterization. It was found that COF is decreased from 0.46 to 0.36 with increasing load (5 to 20 N) at 15 Hz frequency; whereas at 10 Hz frequency COF is measured a constant average value of 0.49. The specific wear rate measured was minimum at 5 N load and 15 Hz frequency combination and was found to be 2.84×10-6 mm3/N m. The wear mechanisms identified during reciprocative sliding wear of composite were abrasion and surface tribo-oxidative reactions with delamination from tribo-zone.

  4. Animal experiments and clinical studies on the role of the vitamins B1, B2, and B6 in radiation protection

    International Nuclear Information System (INIS)

    Schmidt, W.; Wulff, K.; Grimm, U.

    1988-01-01

    The effects of ionizing radiation on erythrocytic transketolase, glutathion reductase, and aspartate-aminotransferase activities with and without addition of coenzymes were studied in 152 Wistar rats, six beagles, and 225 carcinoma patients, as a measure for vitamin B 1 , B 2 , and B 6 supplies. Examinations of 108 patients with mammary carcinoma and 117 patients with cervical, corpus, and ovarian carcinomas were undertaken prior to, during, and after termination of radiotherapy. Two check-up series were run, the first without vitamin B complex therapy, and the second with three daily applications of one dragee each, beginning on the first day of irradiation. The TPP effects recorded indicated no impairment of vitamin B 1 supply. FAD and PLP effects, on the other hand, were significantly increased, which suggested B 2 and B 6 deficits. Vitamin B 2 metabolism was causally impaired by radiation, while the disordes in vitamin B 6 metabolism were attributed to tumour-related causes. The results obtained revealed that both types of disorders can be avoided by prophylactic vitamin B complex treatment. (author)

  5. CDApps: integrated software for experimental planning and data processing at beamline B23, Diamond Light Source.

    Science.gov (United States)

    Hussain, Rohanah; Benning, Kristian; Javorfi, Tamas; Longo, Edoardo; Rudd, Timothy R; Pulford, Bill; Siligardi, Giuliano

    2015-03-01

    The B23 Circular Dichroism beamline at Diamond Light Source has been operational since 2009 and has seen visits from more than 200 user groups, who have generated large amounts of data. Based on the experience of overseeing the users' progress at B23, four key areas requiring the most assistance are identified: planning of experiments and note-keeping; designing titration experiments; processing and analysis of the collected data; and production of experimental reports. To streamline these processes an integrated software package has been developed and made available for the users. The subsequent article summarizes the main features of the software.

  6. Optimization of chromatographic conditions for determination of aflatoxin B1, B2, G1 and G2 by using liquid chromatography-mass Spectrometry

    Science.gov (United States)

    Ramadhaningtyas, Dillani Putri; Aryana, Nurhani; Aristiawan, Yosi; Styarini, Dyah

    2017-11-01

    The optimization of instrument condition and chromatographic separation for analysis of aflatoxin B1, B2, G1 and G2 using liquid chromatography tandem with mass spectrometer detector was conducted in the aim to provide more accurate and reliable analysis results. The aflatoxin known to be serious threat for human health as it is classified as the carcinogenic compounds. The aflatoxin B1, B2, G1 and G2 were selected due to its extensive contamination in various agricultural commodities. The best chromatographic separation was obtained using C-18 column with gradient elution of solvent 5 mM ammonium acetate and 0.1% formic acid in methanol at 7 minutes runtime analysis. The linearity of the detector showed satisfied results as the coefficient determination found to be 0.9994, 0.9996, 0.9998 and 0.9987 for aflatoxin B1, G1, B2, and G2 respectively in the range concentration from 1 to 20 ng/g. The quantifier ion selected for the aflatoxin B1, B2, G1 and G2 was m/z 285.1, 259, 243 and 313 respectively. The instrument precision at these quantifier ions also showed satisfied result with %RSD was around 3.4 to 6.8%. The optimized method present in this study can be used for further sample analysis.

  7. Diversity in peptide recognition by the SH2 domain of SH2B1.

    Science.gov (United States)

    McKercher, Marissa A; Guan, Xiaoyang; Tan, Zhongping; Wuttke, Deborah S

    2018-02-01

    SH2B1 is a multidomain protein that serves as a key adaptor to regulate numerous cellular events, such as insulin, leptin, and growth hormone signaling pathways. Many of these protein-protein interactions are mediated by the SH2 domain of SH2B1, which recognizes ligands containing a phosphorylated tyrosine (pY), including peptides derived from janus kinase 2, insulin receptor, and insulin receptor substrate-1 and -2. Specificity for the SH2 domain of SH2B1 is conferred in these ligands either by a hydrophobic or an acidic side chain at the +3 position C-terminal to the pY. This specificity for chemically disparate species suggests that SH2B1 relies on distinct thermodynamic or structural mechanisms to bind to peptides. Using binding and structural strategies, we have identified unique thermodynamic signatures for each peptide binding mode, and several SH2B1 residues, including K575 and R578, that play distinct roles in peptide binding. The high-resolution structure of the SH2 domain of SH2B1 further reveals conformationally plastic protein loops that may contribute to the ability of the protein to recognize dissimilar ligands. Together, numerous hydrophobic and electrostatic interactions, in addition to backbone conformational flexibility, permit the recognition of diverse peptides by SH2B1. An understanding of this expanded peptide recognition will allow for the identification of novel physiologically relevant SH2B1/peptide interactions, which can contribute to the design of obesity and diabetes pharmaceuticals to target the ligand-binding interface of SH2B1 with high specificity. © 2017 Wiley Periodicals, Inc.

  8. Towards colorless transparent organic transistors: potential of benzothieno[3,2-b]benzothiophene-based wide-gap semiconductors.

    Science.gov (United States)

    Moon, Hanul; Cho, Hyunsu; Kim, Mincheol; Takimiya, Kazuo; Yoo, Seunghyup

    2014-05-21

    Colorless, highly transparent organic thin-film transistors (TOTFTs) with high performance are realized based on benzothieno[3,2-b]benzothiophene (BTBT) derivatives that simultaneously exhibit a wide energy gap and high transport properties. Multilayer transparent source/drain electrodes maintain the transparency, and ultrathin fluoropolymer dielectric layers enable stable, low-voltage operation of the proposed TOTFTs. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. 17 CFR 240.15b2-2 - Inspection of newly registered brokers and dealers.

    Science.gov (United States)

    2010-04-01

    ... brokers and dealers. 240.15b2-2 Section 240.15b2-2 Commodity and Securities Exchanges SECURITIES AND... Regulations Under the Securities Exchange Act of 1934 Registration of Brokers and Dealers § 240.15b2-2 Inspection of newly registered brokers and dealers. (a) Definition. For the purpose of this section the term...

  10. Measuring trace gas emission from multi-distributed sources using vertical radial plume mapping (VRPM) and backward Lagrangian stochastic (bLS) techniques

    Science.gov (United States)

    Two micrometeorological techniques for measuring trace gas emission rates from distributed area sources were evaluated using a variety of synthetic area sources. The accuracy of the vertical radial plume mapping (VRPM) and the backward Lagrangian (bLS) techniques with an open-path optical spectrosco...

  11. Structural stability of the square flux line lattice in YNi2B2C and LuNi2B2C studied with small angle neutron scattering

    DEFF Research Database (Denmark)

    Eskildsen, M.R.; Gammel, P.L.; Barber, B.P.

    1997-01-01

    We have studied the flux line lattice in YNi2B2C and LuNi2B2C, the nonmagnetic end members of the borocarbide superconductors using small angle neutron scattering and transport. For fields, H parallel to c, we find a square symmetric lattice which disorders rapidly above H/H-c2 similar to 0.2, well...... below the ''peak effect'' at H/H-c2 = 0.9. The results for H/H-c2 controlled by the tilt modulus c(44). For H/H-c2 > 0.2, the disordering appears to be associated with the field dependence of the shear modulus, C-66....

  12. Hexagonal OsB2: Sintering, microstructure and mechanical properties

    International Nuclear Information System (INIS)

    Xie, Zhilin; Lugovy, Mykola; Orlovskaya, Nina; Graule, Thomas; Kuebler, Jakob; Mueller, Martin; Gao, Huili; Radovic, Miladin; Cullen, David A.

    2015-01-01

    Highlights: • ReB 2 -type hexagonal OsB 2 powder has been densified by spark plasma sintering. • The sintered OsB 2 contains ∼80 wt.% hexagonal and ∼20 wt.% orthorhombic phases. • The average grain size of the sintered OsB 2 sample was 0.56 ± 0.26 μm. • H = 31 ± 9 GPa and E = 574 ± 112 GPa measured by nanoindentation. - Abstract: The metastable high pressure ReB 2 -type hexagonal OsB 2 bulk ceramics was produced by spark plasma sintering. The phase composition, microstructure, and mechanical behavior of the sintered OsB 2 were studied by X-ray diffraction, optical microscopy, TEM, SEM, EDS, and nanoindentation. The produced ceramics was rather porous and contained a mixture of hexagonal (∼80 wt.%) and orthorhombic (∼20 wt.%) phases as identified by X-ray diffraction and EBSD analysis. Two boron-rich phases, which do not contain Os, were also identified by TEM and SEM/EDS analysis. Nanoindentation measurements yielded a hardness of 31 ± 9 GPa and Young’s modulus of 574 ± 112 GPa, indicating that the material is rather hard and very stiff; however, it is very prone to crack formation and propagation, which is indicative of a very brittle nature of this material. Improvements in the sintering regime are required in order to produce dense, homogeneous and single phase hexagonal OsB 2 bulk ceramics

  13. Li2Sr4B12O23: A new alkali and alkaline-earth metal mixed borate with [B10O18]6− network and isolated [B2O5]4− unit

    International Nuclear Information System (INIS)

    Zhang Min; Pan Shilie; Han Jian; Yang Zhihua; Su Xin; Zhao Wenwu

    2012-01-01

    A novel ternary lithium strontium borate Li 2 Sr 4 B 12 O 23 crystal with size up to 20 mm×10 mm×4 mm has been grown via the top-seeded solution growth method below 730 °C. Single-crystal XRD analyses showed that Li 2 Sr 4 B 12 O 23 crystallizes in the monoclinic space group P2 1 /c with a=6.4664(4) Å, b=8.4878(4) Å, c=15.3337(8) Å, β=102.02(3)°, Z=2. The crystal structure is composed of [B 10 O 18 ] 6− network and isolated [B 2 O 5 ] 4− unit. The IR spectrum further confirmed the presence of both BO 3 and BO 4 groups. TG-DSC and Transmission spectrum were reported. Band structures and density of states were calculated. - Graphical abstract: A new phase, Li 2 Sr 4 B 12 O 23 , has been discovered in the ternary M 2 O–M′O–B 2 O 3 (M=alkali-metal, M′=alkalineearth metal) system. The crystal structure consists of [B 10 O 18 ] 6− network and isolated [B 2 O 5 ] 4− unit. Highlights: ► Li 2 Sr 4 B 12 O 23 is a a novel borate discovered in the M 2 O–M′O–B 2 O 3 (M=alkali-metal, M′=alkaline-earth metal) system. ► Li 2 Sr 4 B 12 O 23 crystal structure has a three-dimensional crystal structure with [B 10 O 18 ] 6− network and isolated [B 2 O 5 ] 4− unit. ► Sr 1 and Sr 2 are located in two different channels constructed by 3 ∞ [B 10 O 18 ] network.

  14. Bradykinin B2 receptor expression in the bronchial mucosa of allergic asthmatics: the role of NF-kB

    NARCIS (Netherlands)

    Ricciardolo, F. L. M.; Petecchia, L.; Sorbello, V.; Di Stefano, A.; Usai, C.; Massaglia, G. M.; Gnemmi, I.; Mognetti, B.; Hiemstra, P. S.; Sterk, P. J.; Sabatini, F.

    2016-01-01

    Bradykinin (BK) mediates acute allergic asthma and airway remodelling. Nuclear factor-kappa B (NF-kB) is potentially involved in BK B2 receptor (B2R) regulation. In this observational cross-sectional study, B2R and NF-kB expression was evaluated in bronchial biopsies from mild asthmatics (after

  15. 26 CFR 1.403(b)-2 - Definitions.

    Science.gov (United States)

    2010-04-01

    ...) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.403(b)-2 Definitions. (a) Application... 1450(b) of the Small Business Job Protection Act of 1996 (110 Stat. 1755, 1814) for special rules...

  16. Electronic structure and vibrational properties of KRbAl{sub 2}B{sub 2}O{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Atuchin, V.V. [Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 90, 630090 (Russian Federation); Adichtchev, S.V. [Laboratory of Condensed Matter Spectroscopy, Institute of Automation and Electrometry, SB RAS, Novosibirsk 90, 630090 (Russian Federation); Bazarov, B.G.; Bazarova, Zh.G. [Laboratory of Oxide Systems, Baikal Institute of Nature Management, SB RAS, Ulan-Ude 47, 670047 (Russian Federation); Gavrilova, T.A. [Laboratory of Nanodiagnostics and Nanolithography, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090 (Russian Federation); Grossman, V.G. [Laboratory of Oxide Systems, Baikal Institute of Nature Management, SB RAS, Ulan-Ude 47, 670047 (Russian Federation); Kesler, V.G. [Laboratory of Physical Principles for Integrated Microelectronics, Institute of Semiconductor Physics, Novosibirsk, 630090 (Russian Federation); Meng, G.S. [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, P.O. Box 2711, Beijing 100190 (China); Key Laboratory of Quantum Information, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, Anhui 230026 (China); Lin, Z.S., E-mail: zslin@mail.ipc.ac.cn [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, P.O. Box 2711, Beijing 100190 (China); Surovtsev, N.V. [Laboratory of Condensed Matter Spectroscopy, Institute of Automation and Electrometry, SB RAS, Novosibirsk 90, 630090 (Russian Federation)

    2013-03-15

    Graphical abstract: With the KRbAl{sub 2}B{sub 2}O{sub 7} powder formed by solid state synthesis (left), Raman spectrum (right upper) and XPS valence electronic states (right lower) were measured, agreed with the first-principles results. Highlights: ► KRbAl{sub 2}B{sub 2}O{sub 7} powder was obtained by solid state synthesis. ► Vibrational properties of KRbAl{sub 2}B{sub 2}O{sub 7} were determined by unpolarized Raman spectrum. ► Electronic structures of KRbAl{sub 2}B{sub 2}O{sub 7} were measured by XPS. ► Experimental electronic structure is consistent with the first-principles result. ► KRbAl{sub 2}B{sub 2}O{sub 7} has a noticeable refractive indices increase and small NLO effects decrease compared to K{sub 2}Al{sub 2}B{sub 2}O{sub 7}. - Abstract: The physical properties of KRbAl{sub 2}B{sub 2}O{sub 7} have been considered in comparison with those of K{sub 2}Al{sub 2}B{sub 2}O{sub 7} and Rb{sub 2}Al{sub 2}B{sub 2}O{sub 7}. The vibrational parameters of KRbAl{sub 2}B{sub 2}O{sub 7} have been measured by Raman spectroscopy as very similar to those of K{sub 2}Al{sub 2}B{sub 2}O{sub 7}. The electronic structures of KRbAl{sub 2}B{sub 2}O{sub 7} have been evaluated by X-ray photoelectron spectroscopy and ab initio computations using CASTEP package. A noticeable refractive indices increase and small decrease of nonlinear optical properties have been found in KRbAl{sub 2}B{sub 2}O{sub 7} in reference to optical parameters of K{sub 2}Al{sub 2}B{sub 2}O{sub 7}.

  17. Information management: The adoption of order processing for B2B e-commerce

    Directory of Open Access Journals (Sweden)

    F. W. Voges

    2007-11-01

    Full Text Available The management of information flow in the order processing activities of small enterprises is not always understood. An inefficient supply chain is often the result of the lack of timely and accessible inter-firm information and data exchange. Small suppliers often do not have the technology infrastructure and capable resources available for proper integration with supply chains. This research investigated suppliers and fast moving consumer goods (FMCG retailers, adopting business-to-business (B2B e-commerce. Small businesses are the focus of this research, as they contribute to a large portion of the South African economy and play an important role in the supply chains of retailers. Case study research using evidence obtained from nine small, medium and micro enterprises (SMMEs and suppliers located in the Western Cape, South Africa, was used. It was found that small suppliers have different processes for conducting business with various retailers. Literature revealed little evidence of using the Internet as an enabling technology in on-line order processing. From the analysis, nine improvement areas were identified to enhance the conduct of efficient B2B order processing and associated information flow. These improvement areas were merged with four factors that were identified in a framework when adopting e-supply chains. This resulted in the proposition of guidelines for small suppliers when adopting B2B e-commerce for order processing.

  18. First-principles studies for the stability of a graphene-like boron layer on CrB2(0001) and MoB2(0001)

    International Nuclear Information System (INIS)

    Qin Na; Liu Shiyu; Li Zhen; Zhao Hui; Wang Sanwu

    2011-01-01

    With extensive first-principles density-functional-theory calculations, we investigate the stability and the atomic and electronic structures of the CrB 2 (0001) and MoB 2 (0001) surfaces, each with two different terminations. It is found that the boron-terminated surface is energetically more favorable over the wide range of thermodynamically allowed chemical potentials than the metal-terminated surface for both CrB 2 (0001) and MoB 2 (0001), suggesting a stable layer of graphene-like boron on the surfaces. Our results also show the similarities and the differences in relaxation and in bonding characteristics between the boron-terminated and metal-terminated surfaces.

  19. A new superhard material: Osmium diboride OsB 2

    Science.gov (United States)

    Hebbache, M.; Stuparević, L.; Živković, D.

    2006-08-01

    Superhard materials have many industrial applications, wherever resistance to abrasion and wear are important. The synthesis of new superhard materials is one of the great challenges to scientists. We re-examined the phase diagram of the binary osmium-boron system and confirmed the existence of two hexagonal phases, OsB 1.1, Os 2B 3, and an orthorhombic phase, OsB 2. Almost nothing is known about the physical properties of osmium borides. Microhardness measurements show that OsB 2 is extremely hard. Ab initio calculations show that this is due to formation of covalent bonds between boron atoms. OsB 2 is also a low compressibility material. It can be used as hard coating.

  20. EOS MLS Level 1B Data Processing, Version 2.2

    Science.gov (United States)

    Perun, Vincent; Jarnot, Robert; Pickett, Herbert; Cofield, Richard; Schwartz, Michael; Wagner, Paul

    2009-01-01

    A computer program performs level- 1B processing (the term 1B is explained below) of data from observations of the limb of the Earth by the Earth Observing System (EOS) Microwave Limb Sounder (MLS), which is an instrument aboard the Aura spacecraft. This software accepts, as input, the raw EOS MLS scientific and engineering data and the Aura spacecraft ephemeris and attitude data. Its output consists of calibrated instrument radiances and associated engineering and diagnostic data. [This software is one of several computer programs, denoted product generation executives (PGEs), for processing EOS MLS data. Starting from level 0 (representing the aforementioned raw data, the PGEs and their data products are denoted by alphanumeric labels (e.g., 1B and 2) that signify the successive stages of processing.] At the time of this reporting, this software is at version 2.2 and incorporates improvements over a prior version that make the code more robust, improve calibration, provide more diagnostic outputs, improve the interface with the Level 2 PGE, and effect a 15-percent reduction in file sizes by use of data compression.