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Sample records for von yb isotopen

  1. Lifetimes Measurements in 160Yb,162Yb,164Yb,166Yb,168Yb

    International Nuclear Information System (INIS)

    Araddad, S. Y.; El-barouni, A. M.; Rateb, G. M.; Mosbah, D. S.; Elahrash, M. S.; Sergiwa, S. M.

    2004-01-01

    From our measurements of the lifetimes of high spin states in 168 Yb along with the published lifetime data for the nearby even even ytterbium isotopes, 160-168 Yb using the Recoil Distance Method (RDM) and the Doppler Shift Attenuation Method (DSAM) present a great opportunity to probe systematically the relationship between the nuclear shape changes and the reduction in collectivity. (authors)

  2. Balance of groundwaterstreams below dumps with the application of environmental isotopes within hydrogeological examinations. Final report; Bilanzierung von Grundwasserstroemen unter Deponien mit Hilfe von umweltisotopen-hydrologischen Analysen im Rahmen hydrogeologischer Untersuchungen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Geyh, M A; Ays, G

    1995-08-15

    Deponiesickerwaesser eine von der natuerlichen Isotopenzusammensetzung abweichende Markierung haben koennten, die vom Deponieinhalt und Isotopen-Fraktionierungen bei dessen Abbau gepraegt ist. Die Isotopenwerte des Grundwassers ober- oder unterstrom der Deponien wurden zu verschiedenen Jahreszeiten gemessen, um natuerliche und anthropogene Veraenderungen der Isotopenzusammensetzungen im Deponiebereich zu erfassen. Es wurde erwartet, dass die Mobilitaet der chemischen Kontaminanten durch physikalische, chemische und biologische Retardation gegenueber der der isotopisch markierten Wassermolekuele eingeschraenkt sei. Im Abstrom von Hausmuelldeponien koennen mit Hilfe der Sauerstoff- und Kohlenstoff-Isotopenzusammensetzung im Sickerwasser unterschiedlich stark von der Deponie beeinflusste Bereiche voneinander abgegrenzt werden. Die Kohlenstoff-Isotopenzusammensetzung kann zur Verfolgung der Phasen des chemischen Abbaus organischer Inhaltsstoffe eingesetzt werden. In Sonderabfalldeponien treten spezielle Isotopen-Effekte auf, die mit der andersartigen Zusammensetzung der Inhaltsstoffe zu erklaeren sind. (orig.)

  3. YB0 HAS LANDED

    CERN Multimedia

      On Feb 28th after a majestic descent of 90m taking 11 hours, the 2000t YB0 central wheel of CMS, containing the superconducting solenoid, gently touched down on the floor of the experimental cavern UXC55.

  4. YB0 SERVICES INSTALLATION COMPLETED

    CERN Document Server

    The beauty of the completed YB0 was briefly visible at P5 as preparations continue for Tracker installation. A tremendous effort, lasting 7 months and involving more than 100 workers on the busiest days, resulted in 5700 electrical cables, 780 optical cables with 65k fibre channels, and 550 pipes laid on YB0 for HB, EB and Tracker.

  5. Absorption Spectra Of Rbcl:Yb Rbbr:Yb And Rbi:Yb Crystals ...

    African Journals Online (AJOL)

    Single crystals of rubidium chloride, bromide and iodide were doped with substitutional divalent ytterbium, Yb ions, by heating them in ytterbium atmosphere. The absorption spectra of the Yb doped crystals were measured at room and liquid nitrogen temperatures. The spectra were found to consist of intense broad ...

  6. Transportin-1-dependent YB-1 nuclear import

    International Nuclear Information System (INIS)

    Mordovkina, Daria A.; Kim, Ekaterina R.; Buldakov, Ilya A.; Sorokin, Alexey V.; Eliseeva, Irina A.; Lyabin, Dmitry N.; Ovchinnikov, Lev P.

    2016-01-01

    The DNA/RNA-binding protein YB-1 (Y-box binding protein 1) performs multiple functions both in the cytoplasm and the nucleus of the cell. Generally localized to the cytoplasm, under certain conditions YB-1 is translocated to the nucleus. Here we report for the first time a transport factor that mediates YB-1 nuclear import – transportin-1. The YB-1/transportin-1 complex can be isolated from HeLa cell extract. Nuclear import of YB-1 and its truncated form YB-1 (1-219) in in vitro transport assay was diminished in the presence of a competitor substrate and ceased in the presence of transportin-1 inhibitor M9M. Inhibitors of importin β1 had no effect on YB-1 transport. Furthermore, transport of YB-1 (P201A/Y202A) and YB-1 (1–219) (P201A/Y202A) bearing inactivating mutations in the transportin-1-dependent nuclear localization signal was practically abolished. Together, these results indicate that transportin-1 mediates YB-1 nuclear translocation. - Highlights: • Transportin-1 mediates YB-1 nuclear import. • YB-1 nuclear translocation is diminished in the presence of transportin-1 inhibitors. • Mutations in the PY motif of YB-1 NLS prevent its translocation to the nucleus.

  7. von Neumann Morgenstern Preferences

    DEFF Research Database (Denmark)

    Vind, Karl

    von Neumann Morgenstern utility is generalized to von Neumann Morgenstern preferences. The proof is an application of simple hyperplane theorems......von Neumann Morgenstern utility is generalized to von Neumann Morgenstern preferences. The proof is an application of simple hyperplane theorems...

  8. von Neumann Morgenstern Preferences

    DEFF Research Database (Denmark)

    Vind, Karl

    2000-01-01

    von Neumann Morgenstern utility is generalized to von Neumann Morgenstern preferences. The proof is an application of simple hyperplane theorems......von Neumann Morgenstern utility is generalized to von Neumann Morgenstern preferences. The proof is an application of simple hyperplane theorems...

  9. Kondo effect and heavy fermions in Yb compounds

    International Nuclear Information System (INIS)

    Bonville, P.

    1987-01-01

    The Kondo properties of Yb dilute alloys and intermetallics have been investigated using Moessbauer spectroscopy on 170 Yb. In the dilute alloys AuYb and LaBe 13 Yb, the Kondo logarithmic anomaly of the impurity relaxation rate has been detected, and in the concentrated Yb compounds YbBe 13 , YbP and YbAs, and YbCuAl, the manifestations of the interplay between the Kondo effect and the magnetic ordering due to the RKKY interaction have been characterized

  10. Yb valence state in Yb{sub 5}Rh{sub 4}Ge{sub 10}

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Hitoshi; Arita, Masashi; Shimada, Kenya; Namatame, Hirofumi; Taniguchi, Masaki [Hiroshima Synchrotron Radiation Center, Hiroshima University, Higashi-Hiroshima (Japan); Utsumi, Yuki [Synchrotron SOLEIL, L' Orme des Merisiers, Gif-sur-Yvette (France); Katoh, Kenichi [Department of Applied Physics, National Defense Academy, Yokosuka (Japan); Mimura, Kojiro [Graduate School of Engineering, Osaka Prefecture University, Sakai (Japan); Ueda, Shigenori [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science, Hyogo (Japan); Quantum Beam Unit, National Institute for Materials Science, Tsukuba (Japan); Yamaoka, Hitoshi [RIKEN SPring-8 Center, Hyogo (Japan); Rousuli, Awabaikeli [Graduate School of Science, Hiroshima University, Higashi-Hiroshima (Japan); Umeo, Kazunori [NBARD, Hiroshima University, Higashi-Hiroshima (Japan)

    2017-06-15

    Temperature- and pressure-dependent Yb valence state in Yb{sub 5}Rh{sub 4}Ge{sub 10} has been investigated by means of Yb 3d hard X-ray photoemission spectroscopy (HAXPES) and Yb L{sub 3} absorption spectroscopy (XAS). The mean Yb valence derived from the Yb 3d HAXPES is estimated to be ∝2.78 at 300 K and decreases to ∝2.74 at 20 K. On the other hand, the Yb valence deduced from the Yb L{sub 3} XAS at 300 K is almost constant with ∝2.81 in the pressure range between 9.2 and 34.7 GPa. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Cryogenic Yb: YAG Thin-Disk Laser

    Science.gov (United States)

    2016-09-09

    as a 4- level laser. Its absorption and emission cross-sections increase, and its thermal conductivity improves. Yb:YAG thin disk laser performance...Air Force Base, NM USA 87117 4RINI Technologies, 582 South Econ Circle, Oviedo, FL USA 32765 Keywords: Laser materials; Lasers, ytterbium...temperatures, Yb:YAG behaves as a 4- level laser. Its absorption and emission cross-sections increase, and its thermal conductivity improves. Yb:YAG

  12. Alloying of Yb-Cu and Yb-Ag utilizing liquid ammonia metal solutions of ytterbium

    International Nuclear Information System (INIS)

    Imamura, H.; Yoshimura, T.; Sakata, Y.

    2003-01-01

    In the course of the studies on preparation of novel compounds using the dissolution of Eu or Yb metals in liquid ammonia, the formation of Yb-Cu and Yb-Ag intermetallic films has been found. When Cu or Ag metal powders were placed in a reactor containing a solution of Yb metal in liquid ammonia, the dissolved Yb readily react with the Cu or Ag metal particles to form surface alloy compounds. X-ray diffraction of Yb-Cu showed that upon thermal treatment above 673 K, the Yb metal deposited on the Cu particles reacted together to be transformed into the YbCu 6.5 intermetallic compound. A characteristic endothermic peak at 749 K, due to alloying of Yb-Cu, was observed by the differential scanning calorimeter measurements. By use of the high reactivity of liquid ammonia metal solutions of ytterbium, it was found that the ytterbium intermetallic films were readily formed under mild conditions. Yb-Cu and Yb-Ag exhibited enhanced catalytic activity for the hydrogenation of ethene as a result of alloying

  13. Preparation and spectroscopic properties of Yb-doped and Yb-Al-codoped high silica glasses

    International Nuclear Information System (INIS)

    Qiao Yanbo; Wen Lei; Wu Botao; Ren Jinjun; Chen Danping; Qiu Jianrong

    2008-01-01

    Yb-doped and Yb-Al-codoped high silica glasses have been prepared by sintering nanoporous glasses. The absorption, fluorescent spectra and fluorescent lifetimes have been measured and the emission cross-section and minimum pump intensities were calculated. Codoping aluminum ions enhanced the fluorescence intensity of Yb-doped high silica glass obviously. The emission cross-sections of Yb-doped and Yb-Al-codoped high silica glasses were 0.65 and 0.82 pm 2 , respectively. The results show that Yb-Al-codoped high silica glass has better spectroscopic properties for a laser material. The study of high silica glass doped with ytterbium is helpful for its application in Yb laser systems, especially for high-power and high-repetition lasers

  14. Are there non-statistical effects in /sup 173/Yb(n,gamma)/sup 174/Yb?

    International Nuclear Information System (INIS)

    Pospisil, S.; Becvar, F.; Chrien, R.E.; Kopecky, J.

    1987-01-01

    The resonance-averaged capture of neutrons in 173 Yb has been studied at energy of 2 keV. With a statistical significance of 99.5% an enhancement of E1-transition to the neutron 2QP levels in 174 Yb is observed. 8 refs

  15. Ellis Von Creveld Syndrome

    Directory of Open Access Journals (Sweden)

    Afshar H

    1999-01-01

    Full Text Available One patient with Ellis Von Creveld syndrome contains: dwarfism, congenital heart"ndisease, ectodermal dysplasia, polyductyly, an abnormally wide labial frenum and maxillary"nmolars with single root.

  16. Luminescent properties of LuAG:Yb and YAG:Yb single crystalline films grown by Liquid Phase Epitaxy method

    International Nuclear Information System (INIS)

    Zorenko, Yu; Zorenko, T.; Gorbenko, V.; Voznyak, T.; Popielarski, P.; Batentschuk, M.; Osvet, A.; Brabec, Ch; Kolobanov, V.; Spasky, D.; Fedorov, A.

    2016-01-01

    In this work, investigation of the spectroscopic parameters of the luminescence of Yb"3"+ ions in single crystalline films of Lu_3Al_5O_1_2 and Y_3Al_5O_1_2 garnets was performed using the synchrotron radiation excitation with the energy in the range of Yb"3"+ charge transitions (CT), exciton range and the onset of interband transitions of these garnets. The basic spectroscopic parameters of the Yb"3"+ CT luminescence in LuAG and YAG hosts were determined and summarized with taking into account the differences in the band gap structure of these garnets. - Highlights: • Single crystalline films of Yb doped LuAG and YAG garnets were grown by LPE method. • Yb"3"+ luminescence of LuAG:Yb and YAG:Yb film were studied using synchrotron radiation. • Basic parameters of Yb"3"+ charge transfer luminescence in LuAG and YAG were determined.

  17. Lars von Triers film

    DEFF Research Database (Denmark)

    Nielsen, Lisbeth Overgaard

    2007-01-01

    Afhandlingen undersøger Lars von Triers filmæstetik, som den kommer til udtryk i spillefilmene fra perioden 1984-2007. Afhandlingen analyserer de enkelte films stil, virkningsstrategi og betydningsdannelse.......Afhandlingen undersøger Lars von Triers filmæstetik, som den kommer til udtryk i spillefilmene fra perioden 1984-2007. Afhandlingen analyserer de enkelte films stil, virkningsstrategi og betydningsdannelse....

  18. Growth and laser action of Yb: YVO4 crystals with low Yb doping concentration

    Science.gov (United States)

    Zhong, Degao; Teng, Bing; Li, Jianhong; Zhang, Shiming; Zhang, Bingtao; Wang, Chao; Tian, Xueping; Liu, Junhai

    2012-11-01

    Yb: YVO4 single crystals with low doping concentrations of Yb3+ less than 0.3 at% were grown using the Czochralski method. The polarized absorption spectra were measured at room temperature. Strong anisotropy exists in the absorption spectra, resulting in almost entirely different features for π-polarization and σ-polarization. The laser emission spectrum and relationship curve between the output power and absorbed pump power (Pabs) were measured. The continuous-wave laser action of Yb: YVO4 single crystal in a range of 1020.4-1026.3 nm was realized by using a high-power diode laser as the pump source.

  19. Resonance transition array of Yb IV

    International Nuclear Information System (INIS)

    Kaufman, V.; Sugar, J.

    1976-01-01

    Nineteen pairs of lines in the wavelength range of 800--1300 A were identified as transitions to the two levels of the ground term of Yb IV, 4f 13 2 F. The 2 F 5 / 2 -- 2 F 7 / 2 interval is 10 214.0 cm -1 with an rms deviation of 0.4 cm -1

  20. Nuclear spectroscopic studies in 162Yb

    International Nuclear Information System (INIS)

    Behrens, H.

    1980-01-01

    The decay of the highly excited 162 Yb nuclei formed in the reaction 150 Sm( 16 O,4n) 162 Yb to the ground state was studied using different gamma detectors and an electron spectrometer, a so called mini-orange. The isotope 162 Yb was moreover produced and spectroscoped by the beta-decay of 162 Lu. For the identification of decay cascades, which were passed after the fusion, and for the determination of the multipolarity of the contributing energy transitions a series of experiments took place: The excitation functions and the angular distributions of the emitted gamma radiation was measured, the conversion coefficients of important transitions were determined, and coincidence events between two detectors occasionally were registrated and analyzed. In the beta decay measurement an assignment of gamma transitions to 162 Yb followed due to the lifetime, under which they occured. The found states of 162 Yb upto spins of 22 h/2π and excitation energies above 5 MeV belong to five rotational bands. The yrast band shows a weak backbending. Corresponding to their spins and parities the bands can be reduced to intrinsic excitation of two quasineutrons. The analysis of the beta-decay of 162 Lu, which takes place from three states in 162 Lu, leads to the lowest levels of the gamma-vibrational band and the band head of the beta band. The microscopic interpretation of the rotational bands and the description of the backbending behaviour are as the interpretation of the states involved at the beta decay in agreement with experimental and theoretical results for neighbouring ytterbium isotopes. (orig.) [de

  1. Rhizostomeen von Manila

    NARCIS (Netherlands)

    Stiasny, G.

    1924-01-01

    Die hier beschriebene kleine Scyphomedusen-Sammlung wurde von Herrn Director P. B. Sivickis, Dept. of Zoology, University of Philippines, Manila, dem Rijksmuseum van Natuurlijke Historie in Leiden überwiesen. Das Material wurde im December 1922 in Manila-bay gefischt und befindet sich in bestem

  2. Schmetterlinge von Madeira

    NARCIS (Netherlands)

    Martin, K.

    1941-01-01

    Wer auf einer ozeanischen Insel Schmetterlinge sammeln will, darf seine Erwartungen nicht zu hoch spannen; aber dennoch waren meine Frau und ich sehr enttäuscht, als uns auf einer Reise nach Madeira von einer dort angesessenen, gebildeten Dame gesagt wurde, sie habe auf der Insel niemals einen

  3. Biologischer Anbau von Strauchbeeren

    OpenAIRE

    Schmid, Andi

    2004-01-01

    Das Merkblatt enthält auf Österreich angepasste, praxisnahe Informationen zur Produktion von hochwertigen Strauchbeeren wie Himbeeren, Brombeeren, Johannisbeeren, Stachelbeeren und Heidelbeeren. Weiterhin: übersichtliche Hinweise zur Planung, Standortwahl, Sortenauswahl, Bodenvorbereitung und Pflanzung, Bewässerung, Nährstoffversorgung, Witterungsschutz, Beikrautregulierung, Ernte und Lagerung. (Diese Publikation enthält spezifische Informationen für Österreich)

  4. Excited negative parity bands in 160Yb

    Science.gov (United States)

    Saha, A.; Bhattacharjee, T.; Curien, D.; Dedes, I.; Mazurek, K.; Banerjee, S. R.; Rajbanshi, S.; Bisoi, A.; de Angelis, G.; Bhattacharya, Soumik; Bhattacharyya, S.; Biswas, S.; Chakraborty, A.; Das Gupta, S.; Dey, B.; Goswami, A.; Mondal, D.; Pandit, D.; Palit, R.; Roy, T.; Singh, R. P.; Saha Sarkar, M.; Saha, S.; Sethi, J.

    2018-03-01

    Negative parity rotational bands in {} 70160Yb{}90 nucleus have been studied. They were populated in the 148Sm(16O, 4n)160Yb reaction at 90 MeV. The gamma-coincidence data have been collected using Indian National Gamma Array composed of twenty Compton suppressed clover germanium (Ge) detectors. Double gating on triple gamma coincidence data were selectively used to develop the decay scheme for these negative parity bands by identifying and taking care of the multiplet transitions. The even- and odd-spin negative parity bands in 160Yb have been studied by comparing the reduced transition probability ratios with the similar bands in neighbouring even-even rare earth nuclei. It is concluded that the concerned odd-spin and even-spin bands are not signature partners and that their structures are compatible with those of the ‘pear-shape’ and ‘pyramid-shape’ oscillations, respectively, the octupole shapes superposed with the quadrupole shape of the ground-state.

  5. Melt processing of Yb-123 tapes

    International Nuclear Information System (INIS)

    Athur, S. P.; Balachandran, U.; Salama, K.

    2000-01-01

    The innovation of a simple, scalable process for manufacturing long-length conductors of HTS is essential to potential commercial applications such as power cables, magnets, and transformers. In this paper the authors demonstrate that melt processing of Yb-123 tapes made by the PIT route is an alternative to the coated conductor and Bi-2223 PIT tape fabrication techniques. Ag-clad Yb-123 tapes were fabricated by groove rolling and subsequently, melt processed in different oxygen partial pressures in a zone-melting furnace with a gradient of 140 C/cm. The transition temperatures measured were found to be around 81 K undermost processing conditions. EPMA of the tapes processed under different conditions show the 123 phase to be Ba deficient and Cu and Yb rich. Critical current was measured at various temperatures from 77 K to 4.2 K. The J c increased with decrease in pO 2 . The highest I c obtained was 52 A at 4.2 K

  6. Development of Yb-169 radiation source for new nondestructive inspection

    International Nuclear Information System (INIS)

    Yamabayashi, Hisamichi

    1994-01-01

    As the nondestructive inspection method for large structures, there has been radiography, and X-ray and γ-ray have been used as the radiation. The transmissivity of radiation through materials changes by the energy of the radiation and the density and thickness of the materials. At present about 880 γ-ray radiography apparatuses are used in Japanese private enterprises, and about 70% of them use 192 Ir γ-ray sources, and about 30% use 60 Co or 137 Cs sources. Recently the defect inspection for the worlded parts of thin wall small tubes and so on have become to be regarded as important, and the 169 Yb source that emits lower energy γ-ray is suitable to the purpose. There are many reports that 169 Yb radiography was applied successfully. As the 169 Yb radiation source, pellets and balls are on the market. 169 Yb is made by the neutron irradiation of 168 Yb in nuclear reactors. The characteristics of 169 Yb, the manufacture of 169 Yb radiation sources and the applicability of 169 Yb radiation sources to nondestructive inspection are reported. Also in Japan, many basic experiments on 169 Yb radiation sources have been carried out, and the irradiation apparatuses are small and light, and the control area can be set small. (K.I.)

  7. Single-crystal structure refinement of YbF{sub 2} with a remark about YbH{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Reckeweg, Olaf; DiSalvo, Francis J. [Cornell Univ., Ithaca, NY (United States). Dept. of Chemistry and Chemical Biology

    2017-07-01

    Transparent-yellow single crystals of YbF{sub 2} were obtained as only crystalline product from the solid-state reaction of Yb and teflon designed to yield 'Yb{sub 3}C{sub 3}F{sub 2}' in addition to some amorphous black material. The first single-crystal structure determination of YbF{sub 2} (cubic space group Fm anti 3m, CaF{sub 2}-type structure, a = 559.46(16) pm; R1 = 1.2%, wR2 = 3.2%) was the starting point to compare isostructural binary fluorides MF{sub 2} and hydrides MH{sub 2} (M = Ca, Yb, Eu, Sr and Ba) exhibiting an as-yet unexplained small volume per formula unit for YbH{sub 2}.

  8. Nutzerorientiertes Management von materiellen und immateriellen Informationsobjekten

    OpenAIRE

    Hübsch, Chris

    2001-01-01

    Schaffung einer stabilen, erweiterbaren und skalierbaren Infrastruktur für die Bereitstellung von Diensten im Umfeld von Bibliotheken und ähnlichen wissensanbietenden Einrichtungen unter Verwendung von XML-RPC und Python.

  9. Synthesis and up-conversion emissions of Yb3+/Er3+, Yb3+/Tm3+

    Indian Academy of Sciences (India)

    42

    which has received considerable attention for material studies [25-28]. ... Though the energy gap between the ground state 8S7/2 and the first excited state 6P7/2 of ... XRD pattern (Figure 1a) of the 20 mol% Yb3+, 2 mol% Er3+ co-doped ...

  10. Valence mixing in YbCuAl: a case study

    International Nuclear Information System (INIS)

    Mattens, W.

    1980-01-01

    Results are presented of a study of the valence state of Yb in the intermetallic compound YbCuAl. Both macroscopic physical properties (magnetic susceptibility, heat capacity, thermal expansion, electric resistivity) and microscopic physical properties (neutron inelastic scattering, nuclear magnetic resonance) are determined. The results are compared with a local Fermi liquid theory. (G.T.H.)

  11. Level structures in Yb nuclei far from stable nuclei

    International Nuclear Information System (INIS)

    Hashizume, Akira

    1982-01-01

    Applying n-γ, γ-γ coincidence techniques, the excited levels in 158 Yb and in 157 Yb nuclei were studied. Stress is placed ona neutron detection technique to assign (HI,xn) reactions which produce the nuclei far from β stability line. (author)

  12. Near-yrast spectroscopy of 164Yb and neighbouring nuclei

    International Nuclear Information System (INIS)

    Jonsson, S.; Roy, H. and others.

    1983-03-01

    High-spin states in 164 Yb have been populated in the 152 Sm( 16 0,4n) and 150 Sm( 18 0,4n) reactions. From studies of γ-γ coincidences, γ-ray angular distributions and conversion electron measurements the level scheme has been constructed. The g-band and the S-band have been established to spin and parity 22(sup)+ and 26(sup)+, respectively, and the rotational sequences (π,α)=(-,1) 1 , (-,0) 1 and (-,0) 2 to 23(sup)-, 24(sup)- and 18(sup)-, respectively. The sidebands in 162 , 164 Er and 164 , 166 Yb are discussed. Constructed two-quasineutron configurations and cranked shell model (CSM) calculations are compared with the experimental results in 164 Yb. Residual interactions between quasiparticles in 164 Yb are calculated. Crossing frequencies and the gain in alignment are summarized for the Yb isotopes and the main features are discussed. (author)

  13. Magnetic susceptibility of YbN

    International Nuclear Information System (INIS)

    Zhou, Y.; Bowen, S.P.; Koelling, D.D.; Monnier, R.

    1991-01-01

    Applying the Zwicknagl, Zevin, and Fulde (ZZF) approximation for the spectral densities of the occupied and empty f states resulting from a degenerate-Anderson-impurity model, which incorporates crystal fields, we compute the low-temperature magnetic susceptibility of YbN. The model, in which each crystal-field level couples to the band states with its own hybridization function, has previously been successfully applied without the ZZF approximation to explain the specific-heat structure at low temperatures. The ZZF approximation removes the spurious zero-temperature behavior of the parent noncrossing approximation for the susceptibility. Surprisingly, even at the low crystal-field degeneracy (N=2) of YbN, the Shiba relation is very nearly satisfied. The appropriate experimental impurity susceptibility for comparison is extracted from the measurement by removing an empirical exchange interaction. The resultant Kondo temperature (T 0 =8.49 K) is consistent with previous specific-heat estimates (10--11 K), and the agreement with experiment is good

  14. Vaporization thermodynamics of Pd-rich intermediate phases in the Pd–Yb system

    Energy Technology Data Exchange (ETDEWEB)

    Ciccioli, A., E-mail: andrea.ciccioli@uniroma1.it [Dipartimento di Chimica, Sapienza Università di Roma, p.le Aldo Moro 5, 00185 Roma (Italy); Balducci, G.; Gigli, G. [Dipartimento di Chimica, Sapienza Università di Roma, p.le Aldo Moro 5, 00185 Roma (Italy); Provino, A. [Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova (Italy); Istituto SPIN-CNR, Corso Perrone 24, 16152 Genova (Italy); Palenzona, A. [Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova (Italy); Manfrinetti, P. [Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova (Italy); Istituto SPIN-CNR, Corso Perrone 24, 16152 Genova (Italy)

    2016-02-20

    Highlights: • Vaporization equilibria of Pd–Yb intermediate phases investigated by effusion techniques. • Heats of formation of Pd–Yb compounds determined from decomposition/atomization enthalpies. • Phase diagram of the Pd–Yb system re-drawn. • Influence of the Yb valence state on the thermodynamic properties observed. - Abstract: The vaporization thermodynamics of several intermediate phases in the Pd–Yb system was investigated by means of vaporization experiments performed under Knudsen conditions (KEML, Knudsen Effusion Mass Loss). The following thermal decomposition processes were studied in the overall temperature range 819–1240 K and their enthalpy changes determined: 4 PdYb(s) = Pd{sub 4}Yb{sub 3}(s) + Yb(g); 5/3 Pd{sub 4}Yb{sub 3}(s) = 4/3 Pd{sub 5}Yb{sub 3}(s) + Yb(g); 21/13 Pd{sub 5}Yb{sub 3}(s) = 5/13 Pd{sub 21}Yb{sub 10}(s) + Yb(g); 1/3 Pd{sub 21}Yb{sub 10}(s) = 21/9 Pd{sub 3}Yb(s) + Yb(g). Additional measurements were performed by KEMS (Knudsen Effusion Mass Spectrometry) on a Pd-rich two-phase sample, which allowed to detect both Yb(g) and Pd(g) in the vapor phase and to determine the atomization enthalpy of the Pd{sub 3}Yb phase (Pd-rich composition boundary, Pd{sub 3.08}Yb{sub 0.92}): Pd{sub 3.08}Yb{sub 0.92}(s) = 0.92 Yb(g) + 3.08 Pd(g). The enthalpy of formation of this compound was thereafter determined as −68 ± 2 kJ/mol at. and, by combining this value with the decomposition enthalpies derived by KEML, the enthalpies of formation of the studied Pd–Yb intermediate phases were evaluated (kJ/mol at.): −75 ± 4 (Pd{sub 21}Yb{sub 10}), −75 ± 3 (Pd{sub 5}Yb{sub 3}), −73 ± 3 (Pd{sub 4}Yb{sub 3}), and −66 ± 3 (PdYb). A modified version of the Pd–Yb phase diagram is also reported, re-drawn on the basis of literature data and of new experimental information recently become available.

  15. Level Densities and Radiative Strength Functions in 170,171Yb

    International Nuclear Information System (INIS)

    Agvaanluvsan, U.; Schiller, A.; Becker, J.A.; Berstein, L.A.; Guttormsen, M.; Mitchell, G.E.; Rekstad, J.; Siem, S.; Voinov, A.

    2003-01-01

    Level densities and radiative strength functions in 171 Yb and 170 Yb nuclei have been measured with the 171 Yb( 3 He, 3 He(prime) γ) 171 Yb and 171 Yb( 3 He, αγ) 170 Yb reactions. A simultaneous determination of the nuclear level density and the radiative strength function was made. The present data adds to and is consistent with previous results for several other rare earth nuclei. The method will be briefly reviewed and the result from the analysis will be presented. The radiative strength function for 171 Yb is compared to previously published work.

  16. Labelling of ethylenediaminetetramethylene phosphonic acid (EDTMP) with 175Yb

    International Nuclear Information System (INIS)

    Azmairit Aziz

    2009-01-01

    Ytterbium-175 ( 175 Yb) is one of radioisotopes that can be used for therapy due to its β-particle emission (T 1/2 = 4.2 d, E β(max) = 480 keV). Beside that, this radioisotope also emits γ-rays of 113 keV (1.9%), 282 keV (3.1%) and 396 keV (6.5%) which are suitable energy for imaging as long as therapeutic applications. EDTMP could be labeled with radionuclide of 175 Yb as an alternative radiopharmaceutical for bone pain palliation due to bone metastases. Labeling of ethylenediaminetetramethylenephosphonic acid with 175 Yb has been studied. Various influential parameters in labeling conditions i.e. the amount of EDTMP ligand, the pH of labeling, incubation time and the amount of 175 Yb solution were studied in order to obtain high labeling efficiency of 175 Yb-EDTMP. The labeling efficiency was obtained by radiochemical purity that was determined by paper chromatography and paper electrophoresis techniques. The optimum labeling condition was obtained at pH 7, 4 mg of EDTMP ligand, 100 µL (105 µg; 0.6 µmol) of 175 Yb solution and 30 minutes incubation time at room temperature. The complex formed was gave maximum labeling efficiency of 98.81 ± 0.15%. Owing to the results, EDTMP ligand can be labeled with 175 Yb radionuclide with labeling efficiency more than 95%. (author)

  17. Study of the production of 177Lu through 176Yb (n, γ) 177Yb → 177Lu nuclear reaction

    International Nuclear Information System (INIS)

    Silva, Giovana Pasqualini da; Osso Junior, Joao Alberto

    2007-01-01

    The beta minus emitter 177 Lu is a promising therapeutic radioisotope for the curative treatment of cancer using labelled proteins. It has a half - life of T 1/2 = 6.71 day and maximum and average β - energies of 421 and 133 keV, resulting in a short range of radiation in tissue. The decay is accompanied by the emission of low energy γ-radiation with 208.3 keV (11%) and 113 keV (6.4%) suitable for simultaneous imaging, 177 Lu can be produced by two different routes, namely, by irradiation of natural Lu 2 O 3 target ( 176 Lu, 2.6%) or enriched (in 176 Lu) Lu 2 O 3 target, as also by irradiation of Yb target (Yb 2 O 3 ) followed by radiochemical separation of 177 Lu from Yb isotopes. The objective of this work is to study the production of 177 Lu through the indirect 176 Yb(n,γ) 177 Yb → 177 Lu nuclear reaction. The results of the production yield of 177 Lu will be shown and compared with the direct reaction. The method of choice for the chemical separation between Lu and Yb was the ion exchange, using an cation exchange resin in Cl - form and α-HIBA as eluent. Preliminary results showed a good separation of 177 Lu from Yb 2 O 3 indirect targets. (author)

  18. Von der Vielfalt einer Institution

    OpenAIRE

    Kabaum, Marcel; Buck, Marc Fabian

    2013-01-01

    Von der Vielfalt von Universitäten bzw. higher education institutions (HEIs) zu sprechen heißt, sich dem Dickicht an Komplexität zu stellen, das sich zwischen ihren Ideen und Realitäten ausbreitet. Der Text führt in den Sammelband "Ideen und Realitäten von Universitäten" ein und hebt die verschiedenen disziplinären Sichtweisen sowie die internationale Breite - Deutschland, Südamerika, USA, Afghanistan und China - der Beiträge hervor. (DIPF/Orig.)

  19. Alejandro Von Humboldt

    Directory of Open Access Journals (Sweden)

    Gerardo Paz Otero

    1965-09-01

    Full Text Available Diverso fue y sigue siéndolo, el destino de los dos hermanos Humboldt, Guillermo y Alejandro. Sino que se inicia con el nacimiento: Guillermo, el mayor, nace el 22 de junio de 1767 en Potsdam, residencia de los emperadores prusianos, la ciudad de los palacios imperiales, el imperio del militarismo germano; su cuna se meció cerca al palacete de Sans-Soussi, donde Federico el Grande forja ba el poderío de Prusia, cultivaba las ciencias y las artes, anfitrionaba a los intelectuales de Europa, y era "vasallo espiritual de Volta ire", según la aguda frase de Goethe. Alejandro viene al mundo dos años después (14 de septiembre de 1769 en Berlín, en la casa burguesa de la Jagerstrasse (calle del cazador que su madre Elizabeth von Humboldt heredara de su primer esposo.

  20. Kleben von Kunststoff mit Metall

    CERN Document Server

    Brockmann, W; Käufer, H

    1989-01-01

    Das Buch behandelt das Kleben von Kunststoffen mit Metallen in einer fur den Praktiker verstandlichen und umsetzbaren Form. Es leitet zu Klebeverfahren an, die optimale Ergebnisse hinsichtlich Qualitat, Dauerhaftigkeit und Wirtschaftlichkeit liefern.

  1. Thermodynamic and transport properties of YbNi 4Cd

    Science.gov (United States)

    Lee, J.; Park, H.; Lee-Hone, N. R.; Broun, D. M.; Mun, E.

    2018-05-01

    The single crystal growth and the physical properties of the intermetallic compounds R Ni4Cd (R =Y and Yb) which crystallize in the face-centered cubic (fcc) MgCu4Sn -type structure (space group F 4 ¯3 m ) are discussed. Thermodynamic and transport properties of YbNi4Cd are studied by measuring the magnetization, electrical resistivity, and specific heat. The magnetic susceptibility measurement shows that the 4 f electrons of Yb3 + ions are well localized. The electrical resistivity and specific heat exhibits an antiferromagnetic ordering below TN=0.97 K. Applying the field along the [111] direction results in the suppression of TN below 0.4 K at the critical field Hc˜4.5 kOe. No non-Fermi liquid behavior has been observed in the vicinity of Hc. Above Hc, the magnetoresistivity shows an unconventional temperature dependence ρ (T ) =ρ0+A Tn with n >2 , suggesting that an additional scattering mechanism in the resistivity needs to be considered. Based on the analysis of experimental results, we conclude that the Yb3 + moments and conduction electrons are weakly coupled. Despite the antiferromagnetic ordering below TN, YbNi4Cd exhibits a large frustration parameter | θp/TN|˜16 , where the magnetic Yb3 + ions occupy the tetrahedra on the fcc lattice.

  2. Lifetimes of high-spin states in {sup 162}Yb

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, M.P.; Janssens, R.V.F.; Henry, R.G. [and others

    1995-08-01

    A measurement on lifetimes of high-spin states in the yrast and near-yrast rotational bands in {sup 162}Yb was carried out at ATLAS in order to determine the evolution of collectivity as a function of angular momentum using the {sup 126}Te({sup 40}Ar,4n){sup 162}Yb reaction at 170 MeV. Previous lifetime measurements in the {sup 164,166,168}Yb isotopes showed a dramatic decrease in the transition quadrupole moment Q{sub t} with increasing spin. It was suggested that this decrease in Q{sub t} is brought about by the rotationally-induced deoccupation of high-j configurations, mainly i{sub 13/2} neutrons. If this interpretation is correct, the heavier isotopes should have a larger decrease in Q{sub t} than the lighter mass nuclides due to the position of the Fermi surface in the i{sub 13/2} subshell. Indeed, {sup 160}Yb does not show a clear decrease in Q{sub t} at high spin. No high spin lifetime information exists for {sup 162}Yb, thus this experiment fills the gap of measured Q{sub t}`s in the light Yb series. The data is currently being analyzed.

  3. Assessment of effect of Yb3+ ion pairs on a highly Yb-doped double-clad fibre laser

    Science.gov (United States)

    Vallés, J. A.; Martín, J. C.; Berdejo, V.; Cases, R.; Álvarez, J. M.; Rebolledo, M. Á.

    2018-03-01

    Using a previously validated characterization method based on the careful measurement of the characteristic parameters and fluorescence emission spectra of a highly Yb-doped double-clad fibre, we evaluate the contribution of ion pair induced processes to the output power of a double-clad Yb-doped fibre ring laser. This contribution is proved to be insignificant, contrary to analysis by other authors, who overestimate the role of ion pairs.

  4. Magnetic linear dichroism in x-ray emission spectroscopy: Yb in Yb3 Fe5 O12

    NARCIS (Netherlands)

    Groot, F.M.F. de; Krisch, M.H.; Sette, F.; Vogel, J.

    2000-01-01

    A magnetic linear dichroism MLD effect of up to 5% has been observed in the 2p 1/2 4d x-ray emission spectrum of Yb in Yb 3 Fe 5 O 12 . The spectral shape is well reproduced with an atomic multiplet calculation of the 4d to 2p decay. It is shown that the details of the spectral shapes are

  5. Richard von Volkmann

    Science.gov (United States)

    Willy, Christian; Schneider, Peter; Engelhardt, Michael; Hargens, Alan R.

    2008-01-01

    Richard von Volkmann (1830–1889), one of the most important surgeons of the 19th century, is regarded as one of the fathers of orthopaedic surgery. He was a contemporary of Langenbeck, Esmarch, Lister, Billroth, Kocher, and Trendelenburg. He was head of the Department of Surgery at the University of Halle, Germany (1867–1889). His popularity attracted doctors and patients from all over the world. He was the lead physician for the German military during two wars. From this experience, he compared the mortality of civilian and war injuries and investigated the general poor hygienic conditions in civilian hospitals. This led him to introduce the “antiseptic technique” to Germany that was developed by Lister. His powers of observation and creativity led him to findings and achievements that to this day bear his name: Volkmann’s contracture and the Hueter-Volkmann law. Additionally, he was a gifted writer; he published not only scientific literature but also books of children’s fairy tales and poems under the pen name of Richard Leander, assuring him a permanent place in the world of literature as well as orthopaedics. PMID:18196438

  6. Aggregation und Management von Metadaten im Kontext von Europeana

    Directory of Open Access Journals (Sweden)

    Gerda Koch

    2017-09-01

    Full Text Available Mit dem In-Beziehung-Setzen und Verlinken von Daten im Internet wird der Weg zur Umsetzung des semantischen Webs geebnet. Erst die semantische Verbindung von heterogenen Datenbeständen ermöglicht übergreifende Suchvorgänge und späteres „Machine Learning“. Im Artikel werden die Aktivitäten der Europäischen Digitalen Bibliothek im Bereich des Metadatenmanagements und der semantischen Verlinkung von Daten skizziert. Dabei wird einerseits ein kurzer Überblick zu aktuellen Forschungsschwerpunkten und Umsetzungsstrategien gegeben, und darüber hinaus werden einzelne Projekte und maßgeschneiderte Serviceangebote für naturhistorische Daten, regionale Kultureinrichtungen und Audiosammlungen beschrieben.

  7. Dielectric relaxation in Yb-doped SrZrO3

    International Nuclear Information System (INIS)

    Kamishima, O; Abe, Y; Ishii, T; Kawamura, J; Hattori, T

    2004-01-01

    The dielectric constant of the proton conductor SrZr 1-x Yb x O 3 (x 0-0.1) was measured as a function of temperature and frequency. Two well-defined relaxation peaks were observed in SrZrO 3 doped with more than 1 mol% of Yb. The assignment of the two dielectric relaxations is discussed in terms of IR spectra and by free energy calculation for a miscibility of dopant Yb ions. The Yb concentration dependence of the relaxation strength of the two dielectric relaxations is in agreement with the results calculated from the free energy. The two relaxations can be assigned to a reorientation of a single Yb-OH dipole and of Yb-OH dipoles associated with Yb-clusters. The attractive energy for Yb-clustering in SrZrO 3 is evaluated at about -85 meV

  8. YB-1 promotes microtubule assembly in vitro through interaction with tubulin and microtubules

    Directory of Open Access Journals (Sweden)

    Baconnais Sonia

    2008-09-01

    Full Text Available Abstract Background YB-1 is a major regulator of gene expression in eukaryotic cells. In addition to its role in transcription, YB-1 plays a key role in translation and stabilization of mRNAs. Results We show here that YB-1 interacts with tubulin and microtubules and stimulates microtubule assembly in vitro. High resolution imaging via electron and atomic force microscopy revealed that microtubules assembled in the presence of YB-1 exhibited a normal single wall ultrastructure and indicated that YB-1 most probably coats the outer microtubule wall. Furthermore, we found that YB-1 also promotes the assembly of MAPs-tubulin and subtilisin-treated tubulin. Finally, we demonstrated that tubulin interferes with RNA:YB-1 complexes. Conclusion These results suggest that YB-1 may regulate microtubule assembly in vivo and that its interaction with tubulin may contribute to the control of mRNA translation.

  9. John von Neumann selected letters

    CERN Document Server

    2005-01-01

    John von Neuman was perhaps the most influential mathematician of the twentieth century, especially if his broad influence outside mathematics is included. Not only did he contribute to almost all branches of mathematics and created new fields, but he also changed post-World War II history with his work on the design of computers and with being a sought-after technical advisor to many figures in the U.S. military-political establishment in the 1940s and 1950s. The present volume is the first substantial collection of (previously mainly unpublished) letters written by von Neumann to colleagues, friends, government officials, and others. The letters give us a glimpse of the thinking of John von Neumann about mathematics, physics, computer science, science management, education, consulting, politics, and war. Readers of quite diverse backgrounds will find much of interest in this fascinating first-hand look at one of the towering figures of twentieth century science.

  10. Automatisierung von HiL Tests

    OpenAIRE

    Asbach, Lennart; Ebrecht, Lars

    2010-01-01

    Automatisierung von HiL Tests. Darstellung und Bewertung einer praktischen Umsetzung. Das Poster zeigt die Motivation, die Durchführung, einen aktuellen Stand und einen Ausblick der Testautomatisierung im Bahnlabor RailSiTe. Als Beispiel dient der Konformitätstest von ETCS-Onboard Zugrechnern, um die Einführung von ETCS zu unterstützen.

  11. Phase precipitation of Yb 2+ ions in RbCl monocrystals monitored ...

    African Journals Online (AJOL)

    Optical absorption spectra of RbCl:Yb2+ crystals have been measured at several elevated temperatures up to 300C. Results showed that in hot RbCl:Yb2+ crystals, the Yb2+ ions occupied lattice sites with effective octahedral, O, point symmetry. Values of an energy parameter , which is an approximate measure of the ...

  12. Homopteren von Java, gesammelt von Herrn Edw. Jacobson

    NARCIS (Netherlands)

    Melichar, L.

    1914-01-01

    Herr Edw. Jacobson hat auf Java in den Jahren 1908— 1910 Homopteren gesammelt und mir die Bearbeitung des gesammelten Materiales übertragen. Die Jacobson’sche Ausbeute ist insoferne bemerkenswert, als dieselbe viele Mikrohomopteren enthält, welche von nichtfachkundigen Sammlern gewöhnlich nicht

  13. Yb:YAG Lasers for Space Based Remote Sensing

    Science.gov (United States)

    Ewing, J.J.; Fan, T. Y.

    1998-01-01

    Diode pumped solid state lasers will play a prominent role in future remote sensing missions because of their intrinsic high efficiency and low mass. Applications including altimetry, cloud and aerosol measurement, wind velocity measurement by both coherent and incoherent methods, and species measurements, with appropriate frequency converters, all will benefit from a diode pumped primary laser. To date the "gold standard" diode pumped Nd laser has been the laser of choice for most of these concepts. This paper discusses an alternate 1 micron laser, the YB:YAG laser, and its potential relevance for lidar applications. Conceptual design analysis and, to the extent possible at the time of the conference, preliminary experimental data on the performance of a bread board YB:YAG oscillator will be presented. The paper centers on application of YB:YAG for altimetry, but extension to other applications will be discussed.

  14. Upconversion dynamics in Yb3+-Ho3+-doped fluoroindate glasses

    International Nuclear Information System (INIS)

    Martin, I.R.; Rodriguez, V.D.; Lavin, V.; Rodriguez-Mendoza, U.R.

    1998-01-01

    The mechanisms and dynamics of the upconversion emissions in Yb 3+ -Ho 3+ -doped fluoroindate glasses by exciting at 975 nm have been analysed. The upconversion efficiencies have been measured as a function of temperature in the range from 12 to 295 K. The temporal evolution of the 545- and 650-nm upconversion emissions obtained under flash excitation at 975 nm in codoped samples with 2.25 mol.% of Yb 3+ and 0.75 mol.% of Ho 3+ cannot be described using the energy migration model. This indicates that at this concentration of Yb 3+ the rapid migration regimen between these ions has not been reached. A model is proposed in order to explain the temporal evolution of these emissions taking into account energy migration between donors and backtransfer processes. (orig.)

  15. Electrodynamically trapped Yb+ ions for quantum information processing

    International Nuclear Information System (INIS)

    Balzer, Chr.; Braun, A.; Hannemann, T.; Wunderlich, Chr.; Paape, Chr.; Ettler, M.; Neuhauser, W.

    2006-01-01

    Highly efficient, nearly deterministic, and isotope selective generation of Yb + ions by one- and two-color photoionization is demonstrated. State preparation and state selective detection of hyperfine states in 171 Yb + is investigated in order to optimize the purity of the prepared state and to time-optimize the detection process. Linear laser-cooled Yb + ion crystals confined in a Paul trap are demonstrated. Advantageous features of different previous ion trap experiments are combined, while at the same time the number of possible error sources is reduced by using a comparatively simple experimental apparatus. This opens a new path toward quantum state manipulation of individual trapped ions, and in particular, to scalable quantum computing

  16. CW Yb:YAG LASER FOR PORTABLE MEASURING SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. M. Ivashko

    2014-01-01

    Full Text Available The theoretical and experimental results of longitudinally continuous-wave diode-pumped Yb:Y3Al5O12 (YAG laser performance for compact field-condition measuring systems were demonstrated. Optimization of laser setup in terms of operation condition in the range of -40 ˚С – +65 ˚С without active thermal stabilization was carried out. Using Yb (10 ат.%:YAG crystal with the length of 3 mm the maximal output power more than 2 W was obtained in the whole of temperature range.

  17. Is YbAs a heavy Fermion system?

    International Nuclear Information System (INIS)

    Monnier, R.; Degiorgi, L.; Delley, B.; Koelling, D.D.

    1989-08-01

    Using parameters extracted from a tight binding fit to an ab initio band structure, the specific heat anomaly observed in YbAs around 5 K is computed within the infinite U limit of the degenerate Anderson impurity model. Applying the renormalization procedure derived in variational treatments of the periodic Anderson model, a quasiparticle Fermi surface with strong nesting features and small mass enhancements is obtained. The results suggest that YbAs is not a ''classical'' heavy Fermion system. 28 refs., 3 figs., 1 tab

  18. Time reversal symmetry violation in the YbF molecule

    Energy Technology Data Exchange (ETDEWEB)

    Sauer, B. E., E-mail: ben.sauer@imperial.ac.uk; Devlin, J. A.; Hudson, J. J.; Kara, D. M.; Smallman, I. J.; Tarbutt, M. R.; Hinds, E. A. [Blackett Laboratory Imperial College London, Centre for Cold Matter (United Kingdom)

    2013-03-15

    We present a summary of the techniques used to test time reversal symmetry by measuring the permanent electric dipole moment of the YbF molecule. The results of a recent measurement (Hudson et al., Nature 473:493, 2011) are reported. We review some systematic effects which might mimic time reversal violation and describe how they are overcome. We then discuss improvements to the sensitivity of the apparatus, including both short term technical enhancements as well as a longer term goal to use laser cooled YbF in the experiment.

  19. Functional conservation of rice OsNF-YB/YC and Arabidopsis AtNF-YB/YC proteins in the regulation of flowering time

    KAUST Repository

    Hwang, Yoon-Hyung; Kim, SoonKap; Lee, Keh Chien; Chung, Young Soo; Lee, Jeong Hwan; Kim, Jeong-Kook

    2016-01-01

    Plant NUCLEAR FACTOR Y (NF-Y) transcription factors play important roles in plant development and abiotic stress. In Arabidopsis thaliana, two NF-YB (AtNF-YB2 and AtNF-YB3) and five NF-YC (AtNF-YC1, AtNF-YC2, AtNF-YC3, AtNF-YC4, and AtNF-YC9) genes regulate photoperiodic flowering by interacting with other AtNF-Y subunit proteins. Three rice NF-YB (OsNF-YB8, OsNF-YB10, and OsNF-YB11) and five rice OsNF-YC (OsNF-YC1, OsNF-YC2, OsNF-YC4, OsNF-YC6, and OsNF-YC7) genes are clustered with two AtNF-YB and five AtNF-YC genes, respectively. To investigate the functional conservation of these NF-YB and NF-YC genes in rice and Arabidopsis, we analyzed the flowering phenotypes of transgenic plants overexpressing the respective OsNF-YB and OsNF-YC genes in Arabidopsis mutants. Overexpression of OsNF-YB8/10/11 and OsNF-YC2 complemented the late flowering phenotype of Arabidopsis nf-yb2 nf-yb3 and nf-yc3 nf-yc4 nf-yc9 mutants, respectively. The rescued phenotype of 35S::OsNF-YC2 nf-yc3 nf-yc4 nf-yc9 plants was attributed to the upregulation of FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1). In vitro and in planta protein–protein analyses revealed that OsNF-YB8/10/11 and OsNF-YC1/2/4/6/7 interact with AtNF-YC3/4/9 and AtNF-YB2/3, respectively. Our data indicate that some OsNF-YB and OsNF-YC genes are functional equivalents of AtNF-YB2/3 and AtNF-YC3/4/9 genes, respectively, and suggest functional conservation of Arabidopsis and rice NF-Y genes in the control of flowering time.

  20. Functional conservation of rice OsNF-YB/YC and Arabidopsis AtNF-YB/YC proteins in the regulation of flowering time

    KAUST Repository

    Hwang, Yoon-Hyung

    2016-01-11

    Plant NUCLEAR FACTOR Y (NF-Y) transcription factors play important roles in plant development and abiotic stress. In Arabidopsis thaliana, two NF-YB (AtNF-YB2 and AtNF-YB3) and five NF-YC (AtNF-YC1, AtNF-YC2, AtNF-YC3, AtNF-YC4, and AtNF-YC9) genes regulate photoperiodic flowering by interacting with other AtNF-Y subunit proteins. Three rice NF-YB (OsNF-YB8, OsNF-YB10, and OsNF-YB11) and five rice OsNF-YC (OsNF-YC1, OsNF-YC2, OsNF-YC4, OsNF-YC6, and OsNF-YC7) genes are clustered with two AtNF-YB and five AtNF-YC genes, respectively. To investigate the functional conservation of these NF-YB and NF-YC genes in rice and Arabidopsis, we analyzed the flowering phenotypes of transgenic plants overexpressing the respective OsNF-YB and OsNF-YC genes in Arabidopsis mutants. Overexpression of OsNF-YB8/10/11 and OsNF-YC2 complemented the late flowering phenotype of Arabidopsis nf-yb2 nf-yb3 and nf-yc3 nf-yc4 nf-yc9 mutants, respectively. The rescued phenotype of 35S::OsNF-YC2 nf-yc3 nf-yc4 nf-yc9 plants was attributed to the upregulation of FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1). In vitro and in planta protein–protein analyses revealed that OsNF-YB8/10/11 and OsNF-YC1/2/4/6/7 interact with AtNF-YC3/4/9 and AtNF-YB2/3, respectively. Our data indicate that some OsNF-YB and OsNF-YC genes are functional equivalents of AtNF-YB2/3 and AtNF-YC3/4/9 genes, respectively, and suggest functional conservation of Arabidopsis and rice NF-Y genes in the control of flowering time.

  1. Identification and characterization of NF-YB family genes in tung tree.

    Science.gov (United States)

    Yang, Susu; Wang, Yangdong; Yin, Hengfu; Guo, Haobo; Gao, Ming; Zhu, Huiping; Chen, Yicun

    2015-12-01

    The NF-YB transcription factor gene family encodes a subunit of the CCAAT box-binding factor (CBF), a highly conserved trimeric activator that strongly binds to the CCAAT box promoter element. Studies on model plants have shown that NF-YB proteins participate in important developmental and physiological processes, but little is known about NF-YB proteins in trees. Here, we identified seven NF-YB transcription factor-encoding genes in Vernicia fordii, an important oilseed tree in China. A phylogenetic analysis separated the genes into two groups; non-LEC1 type (VfNF-YB1, 5, 7, 9, 11, 13) and LEC1-type (VfNF-YB 14). A gene structure analysis showed that VfNF-YB 5 has three introns and the other genes have no introns. The seven VfNF-YB sequences contain highly conserved domains, a disordered region at the N terminus, and two long helix structures at the C terminus. Phylogenetic analyses showed that VfNF-YB family genes are highly homologous to GmNF-YB genes, and many of them are closely related to functionally characterized NF-YBs. In expression analyses of various tissues (root, stem, leaf, and kernel) and the root during pathogen infection, VfNF-YB1, 5, and 11 were dominantly expressed in kernels, and VfNF-YB7 and 9 were expressed only in the root. Different VfNF-YB family genes showed different responses to pathogen infection, suggesting that they play different roles in the pathogen response. Together, these findings represent the first extensive evaluation of the NF-YB family in tung tree and provide a foundation for dissecting the functions of VfNF-YB genes in seed development, stress adaption, fatty acid synthesis, and pathogen response.

  2. Properties of von Neumann entropy

    Indian Academy of Sciences (India)

    disentangled) as seen by moving observers, is used to investigate the properties of von Neumann entropy, as a measure of spin–momentum entanglement. To do so, we partition the total Hilbert space into momentum and spin subspaces so that the ...

  3. von Hippel-Lindau disease

    DEFF Research Database (Denmark)

    Binderup, Marie Louise Mølgaard; Gimsing, Steen; Kosteljanetz, Michael

    2013-01-01

    Endolymphatic sac tumours (ELSTs) of the inner ear occur in 16% of patients with the hereditary tumor syndrome von Hippel-Lindau disease (vHL). ELSTs of all sizes can cause irreversible hearing loss which can, however, be prevented through early diagnosis and treatment. We aim to emphasize the ch...

  4. Comparing Zeeman qubits to hyperfine qubits in the context of the surface code: +174Yb and +171Yb

    Science.gov (United States)

    Brown, Natalie C.; Brown, Kenneth R.

    2018-05-01

    Many systems used for quantum computing possess additional states beyond those defining the qubit. Leakage out of the qubit subspace must be considered when designing quantum error correction codes. Here we consider trapped ion qubits manipulated by Raman transitions. Zeeman qubits do not suffer from leakage errors but are sensitive to magnetic fields to first order. Hyperfine qubits can be encoded in clock states that are insensitive to magnetic fields to first order, but spontaneous scattering during the Raman transition can lead to leakage. Here we compare a Zeeman qubit (+174Yb) to a hyperfine qubit (+171Yb) in the context of the surface code. We find that the number of physical qubits required to reach a specific logical qubit error can be reduced by using +174Yb if the magnetic field can be stabilized with fluctuations smaller than 10 μ G .

  5. Properties of the divalent-Yb compound YbAu{sub 2}Si{sub 2} under extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kaštil, J.; Míšek, M.; Kamarád, J.; Arnold, Z. [Institute of Physics AS CR, v.v.i., Na Slovance 1999/2, 182 21 Prague 8 (Czech Republic); Vlášková, K. [Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, 12116 Prague 2 (Czech Republic); Prchal, J., E-mail: prchal@karlov.mff.cuni.cz [Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, 12116 Prague 2 (Czech Republic); Diviš, M.; Doležal, P.; Prokleška, J.; Valenta, J.; Fikáček, J.; Rudajevová, A.; Kriegner, D. [Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, 12116 Prague 2 (Czech Republic)

    2017-01-15

    Polycrystalline YbAu{sub 2}Si{sub 2} has been prepared by arc melting and a non-standard anisotropic thermal expansion is observed at low temperatures. A non-magnetic Yb{sup 2+} valence state is derived from magnetization, magnetic-susceptibility, heat-capacity and electrical-conductivity measurements in the temperature range from 0.3 to 300 K and at external pressures up to 3.2 GPa. By both experimental and theoretical investigations, YbAu{sub 2}Si{sub 2} is confirmed to be a system with a weak electron-electron correlations and a small electron-phonon interaction. Application of hydrostatic pressure does not reveal any change of state in the range of applied pressures.

  6. [Friedrich Ludwig von Maydelli pildid Baltimaade ajaloost = Friedrich Ludwig von Maydells Baltische Geschichte in Bildern = Friedrich Ludwig von Maydell ́s Baltic history in images] / Ulrike Plath

    Index Scriptorium Estoniae

    Plath, Ulrike, 1972-

    2014-01-01

    Arvustus: Friedrich Ludwig von Maydelli pildid Baltimaade ajaloost = Friedrich Ludwig von Maydells Baltische Geschichte in Bildern = Friedrich Ludwig von Maydell ́s Baltic history in images. Eesti kunstimuuseum, Kadrioru kunstimuuseum. Tallinn 2013

  7. Mass fabrication of homogeneously Yb-doped silica nanoparticles and their spectroscopic properties

    International Nuclear Information System (INIS)

    Xiong Liangming; Sekiya, Edson H; Saito, Kazuya

    2009-01-01

    A large number of homogeneously Yb-doped silica nanoparticles were continually fabricated in a vapor synthesis route, in which the Yb doping level can be well controlled by varying either the heating temperature or the carrier gas flow rate of the Yb precursor. The sizes, shapes, and morphologies of the nanoparticles were examined, and no crystallites and no Yb 2 O 3 clusters were observed in the nanoparticles. These nanoparticles exhibit a clear Yb 3+ -derived absorption at around 973-975 nm and a dependence of the emission intensity and decay time on the doping level, much different from that of sintered pellets.

  8. Electron spin resonance in Yb-based Kondo-lattice systems; Elektronenspinresonanz in Yb-basierten Kondogitter-Systemen

    Energy Technology Data Exchange (ETDEWEB)

    Wykhoff, Jan

    2010-07-07

    The systems Yb{sub 1-w}A{sub 1-w}(Rh{sub 1-x}Co{sub x})(Si{sub 1-y}Ge{sub y}){sub 2} with A=La respectively Lu, as well as YbIr{sub 2}Si{sub 2} are studied. The measurements are presented sortedly for systems, dopings, and external parameters. Beside these external parameters furthermore the orientation of the sample related to the quasistatic magnetic field and the microwave magnetic field was varied.

  9. Sequential growth of sandwiched NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb core–shell–shell nanoparticles for photodynamic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Huang-Yong; Ding, Bin-Bin; Ma, Yin-Chu [Department of Medical Materials and Rehabilitation Engineering, School of Medical Engineering, Hefei University of Technology, Hefei 230009 (China); Sun, Shi-Qi [State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu 730046 (China); Tao, Wei [Department of Medical Materials and Rehabilitation Engineering, School of Medical Engineering, Hefei University of Technology, Hefei 230009 (China); Guo, Yan-Chuan [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Guo, Hui-Chen, E-mail: ghch-2004@hotmail.com [State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu 730046 (China); Yang, Xian-Zhu, E-mail: yangxz@hftu.edu.cn [Department of Medical Materials and Rehabilitation Engineering, School of Medical Engineering, Hefei University of Technology, Hefei 230009 (China); Qian, Hai-Sheng, E-mail: shqian@hfut.edu.cn [Department of Medical Materials and Rehabilitation Engineering, School of Medical Engineering, Hefei University of Technology, Hefei 230009 (China)

    2015-12-01

    Graphical abstract: The monodisperse elliptical NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb core–shell–shell nanoparticles have been synthesized successfully by a facile sequential growth process, which can be used as transducer for photodynamic therapy of cancer cells. - Highlights: • The NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb nanoparticles have been fabricated successfully. • The as-prepared nanoparticles show strong fluorescence excited at 980 or 808 nm. • The nanoparticles were transferred into the aqueous phase via a facile process. • Photosensitizers were loaded into the composites for photodynamic therapy. - Abstract: Upconversion (UC) nanostructures have attracted much interest for their extensive biological applications. In this work, we describe a sequential synthetic route to prepare sandwiched NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb core–shell upconversion nanoparticles. The as-prepared products were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM, JEM 2100F), respectively. The as-prepared core–shell nanoparticles of NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb are composed of elliptical nanoparticles with a length of 80 nm and width of 42 nm, which show efficient upconversion fluorescence excited at 808 nm indicating the formation of core–shell–shell sandwiched nanostructures. In addition, the as-prepared sandwiched NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb core–shell upconversion nanoparticles also show strong upconversion fluorescence excited at 980 nm. Amphiphilic mPEG{sub 2k}-b-PEBEP{sub 6K} copolymers (denoted as PPE) were chosen to transfer these hydrophobic UCNPs into the aqueous phase for biological application. In vitro photodynamic therapy of cancer cells show that the viability of cells incubated with the nanoparticles loaded with MC 540 was significantly lower as compared to the nanoparticles without photosensitizers exposed to NIR laser.

  10. Crystal growth, optical properties, and laser operation of Yb3+-doped NYW single crystal

    Science.gov (United States)

    Cheng, Y.; Xu, X. D.; Yang, X. B.; Xin, Z.; Cao, D. H.; Xu, J.

    2009-11-01

    Laser crystal Yb3+-doped NaY(WO4)2 (Yb:NYW) with excellent quality has been grown by Czochralski technique. The rocking curves from (400) plane of as-grown Yb:NYW crystal was measured and the full-width value at half-maximum was 19.92″. The effective segregation coefficients were measured by the X-ray fluorescence method. The polarized absorption spectra and the fluorescence spectra of Yb:NYW crystal were measured at room temperature. The fluorescence decay lifetime of Yb3+ ion in NYW crystal has been investigated. The spectroscopic parameters of Yb:NYW crystal are calculated and compared with those of Yb:YAG crystal. A continuous wave output power of 3.06 W at 1031 nm was obtained with a slope efficiency of 42% by use of diode pumping.

  11. Luminescence of YbP3O9 upon excitation in the UV-VUV range

    International Nuclear Information System (INIS)

    Stryganyuk, G; Trots, D; Berezovskaya, I; Shalapska, T; Voloshinovskii, A; Dotsenko, V; Zimmerer, G

    2007-01-01

    X-ray powder diffraction and luminescence spectral-kinetic studies have been performed for ytterbium metaphosphate (YbP 3 O 9 ) in the 12-290 K temperature range. The diffraction investigation has shown YbP 3 O 9 to be of monoclinic P 2 1 /c structure at T = 12-290 K. Charge transfer luminescence originating from Yb 3+ ion has been revealed. The carrier confinement within the Yb 3+ charge transfer state is pronounced at T = 12 K. A tendency has been revealed for charge carriers in YbP 3 O 9 to be localized in a trapped exciton state at room temperature. The quenching mechanisms for Yb 3+ charge transfer luminescence and processes competing with the formation of the Yb 3+ charge transfer state are discussed

  12. Effects of Yb on the mechanical properties and microstructures of an Al-Mg alloy

    International Nuclear Information System (INIS)

    Song Min; Wu Zhenggang; He Yuehui

    2008-01-01

    This paper reported a first study of the effects of Yb on the microstructures and mechanical properties of an extruded Al-Mg alloy. It has been shown that the addition of 0.3 wt.% Yb decreases the mechanical properties of the alloy since Mg- and Yb-containing constituents decrease the concentration of Mg solute atoms in Al matrix, and thus the solution strengthening effect. However, the addition of 1 wt.% Yb substantially improves the mechanical behavior of the alloy because the concentration of Yb solute atoms in Al matrix is high enough to generate solution strengthening effect. The improvement in the mechanical properties is due to the large work-hardening and high dislocation density caused by the interaction between dislocations and Yb and Mg solute atoms. The Yb and Mg atoms inhibit the dynamic recovery and recrystallization of the alloy, thus provide a uniformly distributed dislocation structure with high density

  13. Monolithic Yb-fiber femtosecond laser using photonic crystal fiber

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Lægsgaard, Jesper; Turchinovich, Dmitry

    2008-01-01

    We demonstrate, both experimentally and theoretically, an environmentally stable monolithic all-PM modelocked femtosecond Yb-fiber laser, with laser output pulse compressed in a spliced-on low-loss hollow-core photonic crystal fiber. Our laser provides direct fiber-end delivery of 4 nJ pulses...

  14. Graphene Q-switched Yb:KYW planar waveguide laser

    NARCIS (Netherlands)

    Kim, Jun Wan; Choi, Sun Young; Aravazhi, S.; Pollnau, Markus; Griebner, Uwe; Petrov, Valentin; Bae, Sukang; Ahn, Kwang Jun; Yeom, Dong-Il; Rotermund, Fabian

    A diode-pumped Yb:KYW planar waveguide laser, single-mode Q-switched by evanescent-field interaction with graphene, is demonstrated for the first time. Few-layer graphene grown by chemical vapor deposition is transferred onto the top of a guiding layer, which initiates stable Q-switched operation in

  15. Synthesis and characterisation of YbPdSb

    Energy Technology Data Exchange (ETDEWEB)

    Haines, Charles R.S.; Brown, Philip A.C.; Grosche, Friedrich M. [Department of Physics, Cavendish Laboratory, University of Cambridge (United Kingdom)

    2016-07-01

    The intermetallic compound YbPdSb can form in two structures: the low temperature (LT) half-Heusler phase, in which the Yb atoms form a frustrated fcc structure, and the high temperature (HT) Pnma modification. We have prepared phase pure samples of both structures and report resistivity, magnetisation and heat capacity measurements on both. The LT phase is a Kondo lattice system showing large-moment Curie-Weiss paramagnet behaviour without any phase transition anomalies down to the lowest temperatures measured. The resistivity is rather insensitive to temperature from room temperature down to ∝50 K where it decreases steeply with further cooling. By contrast, in the HT phase the magnetic susceptibility displays weak temperature dependence and the resistivity falls with decreasing temperature in the way expected of a weakly correlated metal. These findings suggest that in contrast to the electronic state in the LT structure, the 4f-shell of Yb is completely filled in the HT structure of YbPdSb, presenting an interesting opportunity to study the interplay between lattice and electronic structure within the same compound.

  16. Moments of inertia in 162Yb at very high spins

    International Nuclear Information System (INIS)

    Simon, R.S.; Banaschik, M.V.; Colombani, P.; Soroka, D.P.; Stephens, F.S.; Diamond, R.M.

    1976-01-01

    Two methods have been used to obtain values of the effective moment of inertia of very-high-spin (20h-bar--50h-bar) states populated in heavy-ion compound-nucleus reactions. The 162 Yb nucleus studied has effective moments of inertia smaller than, but approaching, the rigid-body estimate

  17. Spin reorientation behavior in Yb doped YMnO3

    International Nuclear Information System (INIS)

    Sharma, Neetika; Das, A.

    2014-01-01

    RMnO 3 with smaller rare-earths ions (R = Ho to Lu and Y) crystallize in the non-centrosymmetric hexagonal space group P6 3 cm. The magnetic structure of RMnO 3 compounds with (R=Er,Yb.Lu) are described by irreducible representations (IR) Γ 2,4 and Γ 1,3 for those with higher ionic radii (R=Ho,Y,Y-Er). Of recent the magnetic structure of YMnO 3 has been found to be better described by Γ 3 + Γ 4 IR. YbMnO 3 is another hexagonal manganite, with almost similar transition temperature, and basically shares all the physical properties of YMnO 3 , except for the magnetic structure. The magnetic structure of YbMnO 3 can be explained by Γ 2 or Γ 4 . The non collinear nature of magnetic ordering in these compounds arises due to the frustration inherent in these compounds. In this study we have probed the effect of a magnetic ion (Yb) on the magnetic structure of these frustrated isostructural compounds

  18. Ultraviolet and near-infrared luminescence of LaBO3:Ce3+,Yb3+

    Science.gov (United States)

    Wei, Heng-Wei; Shao, Li-Ming; Jiao, Huan; Jing, Xi-Ping

    2018-01-01

    Ce3+ or Yb3+ singly doped LaBO3 and Ce3+-Yb3+ co-doped LaBO3 were prepared by conventional solid state reactions at 1100 °C and their photoluminescence (PL) properties were investigated. The emission spectrum of LaBO3:Ce3+,Yb3+ contains both the Ce3+ ultraviolet (UV) emissions (355 nm and 380 nm) and the Yb3+ near infrared (NIR) emission (975 nm) when excited by the UV light at 270 nm. By using the data of the Ce3+ decay curves and the PL intensities of both Ce3+ and Yb3+, the energy transfer efficiency (η) from Ce3+ to Yb3+, the actual energy transfer efficiency (AE) and the quantum efficiency (Q) of the Yb3+ emission were calculated. In the Ce3+-Yb3+ co-doped LaBO3, Ce3+ can transfer its absorbed energy to Yb3+ efficiently (η can be over 60%), and Yb3+ shows the Q value over 50% when it accepts the energy from Ce3+, which results in the low AE value ∼30%. The energy transfer process from Ce3+ to Yb3+ may be understood by the charge transfer mechanism: Ce3+ + Yb3+ ↔ Ce4+ + Yb2+. Particularly the Ce3+-Yb3+ co-doped LaBO3 phosphor gives the emissions mainly in the UV range and the NIR range with a portion of visible emissions in eye-insensitive range. This unique property may be suitable for applications in anti-counterfeiting techniques and public security affairs.

  19. Genome-wide analysis of the human Alu Yb-lineage

    Directory of Open Access Journals (Sweden)

    Carter Anthony B

    2004-03-01

    Full Text Available Abstract The Alu Yb-lineage is a 'young' primarily human-specific group of short interspersed element (SINE subfamilies that have integrated throughout the human genome. In this study, we have computationally screened the draft sequence of the human genome for Alu Yb-lineage subfamily members present on autosomal chromosomes. A total of 1,733 Yb Alu subfamily members have integrated into human autosomes. The average ages of Yb-lineage subfamilies, Yb7, Yb8 and Yb9, are estimated as 4.81, 2.39 and 2.32 million years, respectively. In order to determine the contribution of the Alu Yb-lineage to human genomic diversity, 1,202 loci were analysed using polymerase chain reaction (PCR-based assays, which amplify the genomic regions containing individual Yb-lineage subfamily members. Approximately 20 per cent of the Yb-lineage Alu elements are polymorphic for insertion presence/absence in the human genome. Fewer than 0.5 per cent of the Yb loci also demonstrate insertions at orthologous positions in non-human primate genomes. Genomic sequencing of these unusual loci demonstrates that each of the orthologous loci from non-human primate genomes contains older Y, Sg and Sx Alu family members that have been altered, through various mechanisms, into Yb8 sequences. These data suggest that Alu Yb-lineage subfamily members are largely restricted to the human genome. The high copy number, level of insertion polymorphism and estimated age indicate that members of the Alu Yb elements will be useful in a wide range of genetic analyses.

  20. Shock, diaschisis and von Monakow

    Directory of Open Access Journals (Sweden)

    Eliasz Engelhardt

    2013-07-01

    Full Text Available The concept of shock apparently emerged in the middle of the 18th century (Whyett as an occurrence observed experimentally after spinal cord transection, and identified as "shock" phenomenon one century later (Hall. The concept was extended (Brown-Séquard and it was suggested that brain lesions caused functional rupture in regions distant from the injured one ("action à distance". The term "diaschisis" (von Monakow, proposed as a new modality of shock, had its concept broadened, underpinned by observations of patients, aiming at distinguishing between symptoms of focal brain lesions and transitory effects they produced, attributable to depression of distant parts of the brain connected to the injured area. Presently, diaschisis is related mainly to cerebrovascular lesions and classified according to the connection fibers involved, as proposed by von Monakow. Depression of metabolism and blood flow in regions anatomically separated, but related by connections with the lesion, allows observing diaschisis with neuroimaging.

  1. Von Hippel–Lindau disease

    Directory of Open Access Journals (Sweden)

    Juhara Haron

    2017-04-01

    Full Text Available Von Hippel–Lindau (VHL disease is a rare autosomal dominantly inherited multisystem disorder characterised by the development of a variety of benign and malignant tumours. We report a case of VHL disease that was inherited by a daughter from her father, who both presented at a young age with progressive headache and were found to have a posterior fossa haemangioblastoma (HB on magnetic resonance imaging (MRI. Multiple benign pancreatic and renal cysts were also noted in both patients.

  2. Microfinance als Geflecht von Anreizproblemen

    OpenAIRE

    Schmidt, Reinhard H.; Tschach, Ingo E.

    2001-01-01

    Während sich die Entwicklungsfinanzierung in Theorie und Praxis generell mit dem Finanzwesen in Entwicklungs- und Transformationsländern befasst, steht im Teilgebiet der Microfinance die Frage im Vordergrund, wie in diesen Ländern der Zugang ärmerer Bevölkerungsgruppen und speziell von Klein- und Kleinstunternehmer(innen), Kleinbauern und sonstigen wirtschaftlich Selbständigen aus eher niedrigen sozialen Schichten zu Kredit und anderen Finanzdiensleistungen verbessert werden kann. Obwohl es e...

  3. Moose von Inselbergen in Benin

    OpenAIRE

    Frahm, Jan-Peter; Porembski, Stefan

    1998-01-01

    Acht Leber- und zehn Laubmoosarten werden von Inselbergen aus Benin angegeben. Fünf der Lebermoose (Acrolejeunea emergens, Riccia atropurpurea, R. congoana, R. discolor, R. moenkemeyeri) und alle Laubmoose (Archidium ohioense, Brachymenium acuminatum, B. exile, Bryum arachnoideum, B. argenteum, Bryum deperssum, Garckea moenkemeyeri, Hyophila involuta, Philonotis mniobryoides und Weissia cf. edentula) werden neu für Benin angegeben. Eight liverworts and ten mosses are reported from inselber...

  4. Entwicklung und Anwendung von Methoden zur Bestimmung von Selen-Spezies in human-biologischem Material

    OpenAIRE

    Jäger, Thomas

    2014-01-01

    Selen ist essentieller Bestandteil von mehr als 25 physiologisch wichtigen menschlichen Enzymen. Der tägliche Bedarf wird überwiegend in Form von organischen Selenverbindungen wie Selenmethionin oder Selenocystein aus der Nahrung aufgenommen. Weitere Expositionswege sind die Einnahme von Nahrungsergänzungsmitteln zur Selensupplementation sowie die inhalative oder dermale Aufnahme von in erster Linie anorganischen Selenverbindungen oder elementarem Selen an Arbeitsplätzen der Selen-verarbeiten...

  5. Post-adsorption process of Yb phosphate nano-particle formation by Saccharomyces cerevisiae

    Science.gov (United States)

    Jiang, MingYu; Ohnuki, Toshihiko; Tanaka, Kazuya; Kozai, Naofumi; Kamiishi, Eigo; Utsunomiya, Satoshi

    2012-09-01

    In this study, we have investigated the post-adsorption process of ytterbium (Yb) phosphate nano-particle formation by Saccharomyces cerevisiae (yeast). The yeast grown in P-rich medium were exposed to 1.44 × 10-4 mol/L Yb(III) solution for 2-120 h, and 2 months at 25 ± 1 °C at an initial pH of 3, 4, or 5, respectively. Ytterbium concentrations in solutions decreased as a function of exposure time. Field-emission scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (FESEM), transmission electron microscopy (TEM), and synchrotron-based extended X-ray absorption fine structure (EXAFS) analyses revealed that nano-sized blocky Yb phosphate with an amorphous phase formed on the yeast cells surfaces in the solutions with Yb. These nano-sized precipitates that formed on the cell surfaces remained stable even after 2 months of exposure at 25 ± 1 °C around neutral pHs. The EXAFS data revealed that the chemical state of the accumulated Yb on the cell surfaces changed from the adsorption on both phosphate and carboxyl sites at 30 min to Yb phosphate precipitates at 5 days, indicating the Yb-phosphate precipitation as a major post-adsorption process. In addition, the precipitation of Yb phosphate occurred on cell surfaces during 7 days of exposure in Yb-free solution after 2 h of exposure (short-term Yb adsorption) in Yb solution. These results suggest that the released P from the inside of yeast cells reacted with adsorbed Yb on cell surfaces, resulting in the formation of Yb precipitates, even though no P was added to the exposure solution. In an abiotic system, the EXAFS data showed that the speciation of sorbed Yb on the reference materials, carboxymethyl cellulose and Ln resin, did not change even when the Yb was exposed to P solution, without forming Yb phosphate precipitates. This result strongly suggests that the cell surface of the yeast plays an important role in the Yb-phosphate precipitation process, not only as a carrier of the

  6. Dr. von Braun Briefing Walt Disney

    Science.gov (United States)

    1965-01-01

    Dr. von Braun began his association with Walt Disney in the 1950s when the rocket scientist appeared in three Disney television productions related to the exploration of space. Years later, Dr. von Braun invited Disney and his associates to tour the Marshall Space Flight Center (MSFC) in Huntsville, Alabama. This photograph is dated April 13, 1965. From left are R.J. Schwinghamer from the MSFC, Disney, B.J. Bernight, and Dr. von Braun.

  7. Wohnquartiersbeschreibung: ein Instrument zur Regionalisierung von Nachbarschaften

    OpenAIRE

    Hoffmeyer-Zlotnik, Jürgen H. P.

    2001-01-01

    'Ausgehend von der Annahme, daß soziale Differenzierung sich in räumlicher Differenzierung niederschlägt, bietet eine Beschreibung der Struktur des näheren Wohnumfeldes die Möglichkeit, das Wohnquartier als Handlungsraum und Sozialisationsinstanz zur Interpretation von Umfragedaten zu nutzen. Das vorliegende Instrumentarium erlaubt es, das Wohnquartier unabhängig von Zensusdaten über Merkmale, die in der eigenen Umfrage erhoben werden, zu charakterisieren.' (Autorenreferat) 'The general hy...

  8. Transport, Thermal, and Magnetic Properties of YbNi3X9 (X = Al, Ga): A Newly Synthesized Yb-Based Kondo Lattice System

    Science.gov (United States)

    Yamashita, Tetsuro; Miyazaki, Ryoichi; Aoki, Yuji; Ohara, Shigeo

    2012-03-01

    We have succeeded in synthesizing a new Yb-based Kondo lattice system, YbNi3X9 (X = Al, Ga). Our study reveals that YbNi3Al9 shows typical features of a heavy-fermion antiferromagnet with a Néel temperature of TN = 3.4 K. All of the properties reflect a competition between the Kondo effect and the crystalline electric field (CEF) effect. The moderate heavy-fermion state leads to an enhanced Sommerfeld coefficient of 100 mJ/(mol\\cdotK2), even if ordered antiferromagnetically. On the other hand, the isostructural gallide YbNi3Ga9 is an intermediate-valence system with a Kondo temperature of TK = 570 K. A large hybridization scale can overcome the CEF splitting energy, and a moderately heavy Fermi-liquid ground state with high local moment degeneracy should form at low temperatures. Note that the quality of single-crystalline YbNi3X9 is extremely high compared with those of other Yb-based Kondo lattice compounds. We conclude that YbNi3X9 is a suitable system for investigating the electronic structure of Yb-based Kondo lattice systems from a heavy-fermion system with an antiferromagnetically ordered ground state to an intermediate-valence system.

  9. YB-1 overexpression promotes a TGF-β1-induced epithelial–mesenchymal transition via Akt activation

    International Nuclear Information System (INIS)

    Ha, Bin; Lee, Eun Byul; Cui, Jun; Kim, Yosup; Jang, Ho Hee

    2015-01-01

    The Y-box binding protein-1 (YB-1) is a transcription/translation regulatory protein, and the expression thereof is associated with cancer aggressiveness. In the present study, we explored the regulatory effects of YB-1 during the transforming growth factor-β1 (TGF-β1)-induced epithelial-to-mesenchymal transition (EMT) in lung adenocarcinoma cells. Downregulation of YB-1 increased E-cadherin promoter activity, and upregulation of YB-1 decreased promoter activity, suggesting that the YB-1 level may be correlated with the EMT. TGF-β1 induced YB-1 expression, and TGF-β1 translocated cytosolic YB-1 into the nucleus. YB-1 overexpression promoted TGF-β1-induced downregulation of epithelial markers, upregulation of mesenchymal markers, and cell migration. Moreover, YB-1 overexpression enhanced the expression of E-cadherin transcriptional repressors via TGF-β1-induced Akt activation. Our findings afford new insights into the role played by YB-1 in the TGF-β1 signaling pathway. - Highlights: • YB-1 regulates E-cadherin expression in A549 cells. • TGF-β1 induces upregulating and nuclear localization of YB-1. • YB-1 overexpression accelerates TGF-β1-induced EMT and cell migration. • YB-1 regulates Snail and Slug expression via Akt activation

  10. Parameters of thermoelectric power and electronic structure of Yb-based compounds of YbM2X2(M=Fe,Co,Ni,Cu; X=Si,Ge) type

    International Nuclear Information System (INIS)

    Levin, E.M.; Kuzhel', B.S.

    1990-01-01

    Thermoelectric power of Yb-based intermetallic alloys YbM 2 Si 2 (M-Co,Ni,Cu) and YbM 2 Ge 2 (M=Fe,Co,Ni) have been investigated and found to have anomalous low-temperature peaks conditioned by intermediate Yb valency. Calculation of electronic structure parameters performed in frames of the localized Fermi-liquid model using experimental data on the thermoelectric power is in good agreement with results of YbCu 2 Si 2 band structure calculation based on the experimental value of the electronic heat capacity with regard for the (2J+1) - fold Yb 2+ degeneration

  11. Luminescence properties and energy transfer processes in YAG:Yb,Er single crystalline films

    International Nuclear Information System (INIS)

    Zorenko, Yu.; Gorbenko, V.; Savchyn, V.; Batentschuk, M.; Osvet, A.; Brabec, C.

    2013-01-01

    The paper is dedicated to the study of the optical properties of YAG:Yb,Er single-crystalline films (SCF) grown by liquid phase epitaxy. The absorption, cathodoluminescence and time-resolved photoluminescence spectra and photoluminescence decay curves were measured for the SCFs with different doping levels of Er 3+ (from 0.6 to 4.2 at.%) and Yb 3+ (from 0.1 to 0.6 at.%). The spectra, excited by synchrotron radiation in the fundamental absorption range of the YAG and in the intraionic absorption bands of both dopants, reveal energy transfer from the YAG host to the Er 3+ and Yb 3+ ions and between these ions. -- Highlights: •Growth of YAG:Yb,Er single crystalline films by LPE method. •Peculiarities of luminescence of YAG:Yb,Er films with different Er–Yb content. •Yb–Er energy transfer processes in YAG hosts

  12. Down-conversion luminescence from (Ce, Yb) co-doped oxygen-rich silicon oxides

    International Nuclear Information System (INIS)

    Heng, C. L.; Wang, T.; Su, W. Y.; Wu, H. C.; Yin, P. G.; Finstad, T. G.

    2016-01-01

    We have studied down-conversion photoluminescence (PL) from (Ce, Yb) co-doped “oxygen rich” silicon oxide films prepared by sputtering and annealing. The Ce"3"+ ∼510 nm PL is sensitive to the Ce concentration of the films and is much stronger for 3 at. % Ce than for 2 at. % Ce after annealing at 1200 °C. The PL emission and excitation spectroscopy results indicate that the excitation of Yb"3"+ is mainly through an energy transfer from Ce"3"+ to Yb"3"+, oxide defects also play a role in the excitation of Yb"3"+ after lower temperature (∼800 °C) annealing. The Ce"3"+ 510 nm photon excites mostly only one Yb"3"+ 980 nm photon. Temperature-dependent PL measurements suggest that the energy transfer from Ce"3"+ to Yb"3"+ is partly thermally activated.

  13. A broadening temperature sensitivity range with a core-shell YbEr@YbNd double ratiometric optical nanothermometer

    Science.gov (United States)

    Marciniak, L.; Prorok, K.; Francés-Soriano, L.; Pérez-Prieto, J.; Bednarkiewicz, A.

    2016-02-01

    The chemical architecture of lanthanide doped core-shell up-converting nanoparticles can be engineered to purposely design the properties of luminescent nanomaterials, which are typically inaccessible to their homogeneous counterparts. Such an approach allowed to shift the up-conversion excitation wavelength from ~980 to the more relevant ~808 nm or enable Tb or Eu up-conversion emission, which was previously impossible to obtain or inefficient. Here, we address the issue of limited temperature sensitivity range of optical lanthanide based nano-thermometers. By covering Yb-Er co-doped core nanoparticles with the Yb-Nd co-doped shell, we have intentionally combined temperature dependent Er up-conversion together with temperature dependent Nd --> Yb energy transfer, and thus have expanded the temperature response range ΔT of a single nanoparticle based optical nano-thermometer under single ~808 nm wavelength photo-excitation from around ΔT = 150 K to over ΔT = 300 K (150-450 K). Such engineered nanocrystals are suitable for remote optical temperature measurements in technology and biotechnology at the sub-micron scale.The chemical architecture of lanthanide doped core-shell up-converting nanoparticles can be engineered to purposely design the properties of luminescent nanomaterials, which are typically inaccessible to their homogeneous counterparts. Such an approach allowed to shift the up-conversion excitation wavelength from ~980 to the more relevant ~808 nm or enable Tb or Eu up-conversion emission, which was previously impossible to obtain or inefficient. Here, we address the issue of limited temperature sensitivity range of optical lanthanide based nano-thermometers. By covering Yb-Er co-doped core nanoparticles with the Yb-Nd co-doped shell, we have intentionally combined temperature dependent Er up-conversion together with temperature dependent Nd --> Yb energy transfer, and thus have expanded the temperature response range ΔT of a single nanoparticle

  14. Monolithic femtosecond Yb-fiber laser with photonic crystal fibers

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Lægsgaard, Jesper; Turchinovich, Dmitry

    We demonstrate a monolithic stable SESAM-modelocked self-starting Yb-fiber laser. A novel PM all-solid photonic bandgap fiber is used for intra-cavity of dispersion management. The ex-cavity final pulse compression is performed in a spliced-on PM hollow-core photonic crystal fiber. The laser...... directly delivers 9 nJ pulses of 275 fs duration with pulse repetition of 26.7MHz....

  15. Thermoelectric nanocrystalline YbCoSb laser prepared layers

    Czech Academy of Sciences Publication Activity Database

    Jelínek, Miroslav; Zeipl, Radek; Kocourek, Tomáš; Remsa, Jan; Navrátil, Jiří

    2016-01-01

    Roč. 122, č. 3 (2016), s. 1-5, č. článku 155. ISSN 0947-8396 R&D Projects: GA ČR(CZ) GA13-33056S Institutional support: RVO:68378271 ; RVO:61389013 Keywords : nanocrystalline YbCoSb * thermoelectric layers * pulsed laser deposition Subject RIV: BM - Solid Matter Physics ; Magnetism; CA - Inorganic Chemistry (UMCH-V) Impact factor: 1.455, year: 2016

  16. Charge transfer luminescence of Yb3+ ions in LiY1-xYbxP4O12 phosphates

    International Nuclear Information System (INIS)

    Stryganyuk, G; Zazubovich, S; Voloshinovskii, A; Pidzyrailo, M; Zimmerer, G; Peters, R; Petermann, K

    2007-01-01

    Spectral-kinetic studies have been performed for LiY 1-x Yb x P 4 O 12 (x = 0; 0.1; 0.9) phosphates at T = 8-320 K using synchrotron radiation for excitation within the 5-17 eV energy range. Mechanisms for the excitation of Yb 3+ charge transfer and f-f luminescence are discussed. The quasimolecular character of Yb 3+ charge transfer luminescence (CTL) is pointed out. The central Yb 2+ ion and hole delocalized over the surrounding ligands are proposed for consideration as a 'charge transfer cluster' (Yb 2+ CT cluster). Possible mechanisms of Yb 3+ CTL quenching are presumed

  17. Spectroscopic properties and quenching processes of Yb3+ in Fluoride single crystals for laser applications

    International Nuclear Information System (INIS)

    Bensalah, A.; Ito, M.; Guyot, Y.; Goutaudier, C.; Jouini, A.; Brenier, A.; Sato, H.; Fukuda, T.; Boulon, G.

    2007-01-01

    Spectroscopic characterization is carried out to identify Stark's levels of Yb 3+ transitions in several fluoride crystals grown either by the Czochralski technique or by the laser-heated pedestal growth method. Yb 3+ concentration dependence of the decay time is analyzed in order to understand involved concentration quenching mechanisms. Laser tests under saphire:Ti pumping are presented for all our materials as well as under diode pumping for Yb:CaF 2

  18. Cold shock protein YB-1 is involved in hypoxia-dependent gene transcription

    International Nuclear Information System (INIS)

    Rauen, Thomas; Frye, Bjoern C.; Wang, Jialin; Raffetseder, Ute; Alidousty, Christina; En-Nia, Abdelaziz; Floege, Jürgen; Mertens, Peter R.

    2016-01-01

    Hypoxia-dependent gene regulation is largely orchestrated by hypoxia-inducible factors (HIFs), which associate with defined nucleotide sequences of hypoxia-responsive elements (HREs). Comparison of the regulatory HRE within the 3′ enhancer of the human erythropoietin (EPO) gene with known binding motifs for cold shock protein Y-box (YB) protein-1 yielded strong similarities within the Y-box element and 3′ adjacent sequences. DNA binding assays confirmed YB-1 binding to both, single- and double-stranded HRE templates. Under hypoxia, we observed nuclear shuttling of YB-1 and co-immunoprecipitation assays demonstrated that YB-1 and HIF-1α physically interact with each other. Cellular YB-1 depletion using siRNA significantly induced hypoxia-dependent EPO production at both, promoter and mRNA level. Vice versa, overexpressed YB-1 significantly reduced EPO-HRE-dependent gene transcription, whereas this effect was minor under normoxia. HIF-1α overexpression induced hypoxia-dependent gene transcription through the same element and accordingly, co-expression with YB-1 reduced HIF-1α-mediated EPO induction under hypoxic conditions. Taken together, we identified YB-1 as a novel binding factor for HREs that participates in fine-tuning of the hypoxia transcriptome. - Highlights: • Hypoxia drives nuclear translocation of cold shock protein YB-1. • YB-1 physically interacts with hypoxia-inducible factor (HIF)-1α. • YB-1 binds to the hypoxia-responsive element (HRE) within the erythropoietin (EPO) 3′ enhancer. • YB-1 trans-regulates transcription of hypoxia-dependent genes such as EPO and VEGF.

  19. Synthesis and molecular structure of YbI(bipy)(DME)2 complex

    International Nuclear Information System (INIS)

    Petrovskaya, T.V.; Fedyushkin, I.L.; Nevodchikov, V.I.; Bochkarev, M.N.; Borodina, N.V.; Eremenko, I.L.; Nefedov, S.E.

    1998-01-01

    The reaction of the ytterbium naphthaline complex [Yb(DME) 2 ] 2 (μ-C 10 H 8 ) with 2,2 ' -bipyridine in DME is found to lead to the formation of the complex with the Yb 2+ atom, YbI(bipy)(DME) 2 (1) containing 2,2 ' -bipyridine radical anion. Complex 1 is characterized by IR and UV spectroscopy, magnetic methods and X-ray analysis [ru

  20. Electronic structure and X-ray spectroscopic properties of YbNi_2P_2

    International Nuclear Information System (INIS)

    Shcherba, I.D.; Bekenov, L.V.; Antonov, V.N.; Noga, H.; Uskokovic, D.; Zhak, O.; Kovalska, M.V.

    2016-01-01

    Highlights: • We present new experimental and theoretical data for YbNi_2P_2. • The presence of divalent and trivalent Yb ion found in YbNi_2P_2. • The calculation show good agreement with the experimental measurements. - Abstract: X-ray absorption spectrum at the Yb L_3 edge and X-ray emission spectra of Ni and P at the K and L_2_,_3 edges have been studied experimentally and theoretically in the mixed valent compound YbNi_2P_2 with ThCr_2Si_2 type crystal structure. The electronic structure of YbNi_2P_2 is investigated using the fully relativistic Dirac linear muffin-tin orbital (LMTO) band-structure method. The effect of the spin–orbit (SO) interaction and Coulomb repulsion U on the electronic structure of YbNi_2P_2 is examined in the frame of the LSDA + SO + U method. The core-hole effect in the final states as well as the effect of the electric quadrupole E_2 transitions have been investigated. A good agreement between the theory and the experiment was found. Both the trivalent and the divalent Yb ions in YbNi_2P_2 are reflected in the experimentally measured Yb L_3 X-ray absorption spectrum simultaneously. We found that the best agreement between the experimental spectrum and sum of the theoretically calculated Yb"2"+ and Yb"3"+ spectra is achieved with 73% ytterbium ions in 2+ state and 27% ions in 3+ state.

  1. Von Willebrand disease protects against arterial thrombosis

    NARCIS (Netherlands)

    Sanders, Y.V.; Eikenboom, J.C.; De Wee, E.M.; Van Der Bom, J.G.; Cnossen, M.H.; Degenaar-Dujardin, M.E.; Fijnvandraat, K.; Kamphuisen, P.W.; Laros-Van Gorkum, B.A.; Meijer, K.; Mauser -Bunschoten, E.P.; Leebee k, F.W.

    Background and Aims: Von Willebrand disease (VWD) is caused by reduced levels of or dysfunctional von Willebrand factor (VWF) and is characterized by a bleeding tendency. It is well known that individuals with high VWF levels have a higher risk for arterial thrombosis. Although it has never been

  2. Research, design and education, Von Humboldt revisited

    NARCIS (Netherlands)

    Bax, M.F.T.; Doevendans, C.H.; Trum, H.M.G.J.; Langenhuizen, Anja; Ouwerkerk, Marieke van; Rosemann, Jurgen

    2001-01-01

    This paper is a result of reflection on the interrelation design-research-cultivation, and on the interpretation of Von Humboldt's maxim: 'Einheit von Forschung und Lehre', which governed the academic world in the past two centuries. It is argued that 'Forschung' should be interpreted as 'Research

  3. Diffusion von Leerstelleninseln auf Cu(111)

    NARCIS (Netherlands)

    Verheij, Laurens K.; Schlößer, Dietmar; Rosenfeld, Georg

    1998-01-01

    Die zufällige Bewegung von Leerstelleninseln wurde bisher vorwiegend in einem Bild beschrieben, das von der Diffusion einzelner Atome ausgeht. In diesem Bild kann man Inseldiffusion durch die Einstein-Beziehung für Brownsche Bewegung ((Δ r)2 = 4 D Δ t) beschreiben. Für die Diffusionskonstante D wird

  4. Liposomal encapsulated Zn-DTPA for removing intracellular 169Yb

    International Nuclear Information System (INIS)

    Blank, M.L.; Cress, E.A.; Byrd, B.L.; Washburn, L.C.; Snyder, F.

    1980-01-01

    Multilamellar liposomes possessing neutral positive or negative charges were tested for their capacity to encapsulate sodium ethylenediaminetetraacetate (EDTA) and for their selectivity in depositing in specific tissues after being injected into rats. Negative-charged liposomes had the greatest trapping efficiency over a wide range of lipid-to-aqueous phase ratios. In contrast, except for lung, liposomal charge had no significant effect on the tissue distribution of encapsulated EDTA; liver and spleen exhibited the highest uptake with all preparations. The proportion of encapsulated EDTA taken up by the liver decreased as the amount of injected liposomes was increased. Free zinc diethylenetriaminepentaacetate (Zn-DTPA) and multilamellar liposomes containing entrapped Zn-DTPA were administered to rats that had been injected with 169 Yb-citrate 24 hr earlier. At doses of 14 mg Zn-DTPA per kg body weight, both free Zn-DPTA and the liposomal-bound Zn-DTPA caused increased removal of 169 Yb from the animals. However, treatment with the liposomal Zn-DTPA caused significantly more of the 169 Yb to be removed than did the free Zn-DTPA treatment by itself. Our data indicate that lipophilic forms of chelators can effectively increase the removal rates of heavy metal contamination in tissues. (author)

  5. Phase stability of AlYB14 sputtered thin films

    International Nuclear Information System (INIS)

    Koelpin, Helmut; Music, Denis; Emmerlich, Jens; Schneider, Jochen M; Henkelman, Graeme; Munnik, Frans

    2009-01-01

    AlYB 14 (Imma) thin films were synthesized by magnetron sputtering. On the basis of x-ray diffraction, no phases other than crystalline AlYB 14 could be identified. According to electron probe microanalysis, energy dispersive x-ray analysis and elastic recoil detection analysis, the Al and Y occupancies vary in the range of 0.73-1.0 and 0.29-0.45, respectively. Density functional theory based calculations were carried out to investigate the effect of occupancy on the stability of Al x Y y B 14 (x,y = 0.25, 0.5, 0.75, 1). The mean effective charge per icosahedron and the bulk moduli were also calculated. It is shown that the most stable configuration is Al 0.5 YB 14 , corresponding to a charge transfer of two electrons from the metal atoms to the boron icosahedra. Furthermore, it is found that the stability of a configuration is increased as the charge is homogeneously distributed within the icosahedra. The bulk moduli for all configurations investigated are in the range between 196 and 220 GPa, rather close to those for known hard phases such as α- Al 2 O 3 .

  6. Von Hippel-Lindau Disease

    Directory of Open Access Journals (Sweden)

    Hes Frederik J

    2005-11-01

    Full Text Available Abstract A germline mutation in the Von-Hippel Lindau (VHL gene predisposes carriers to development of abundantly vascularised tumours in the retina, cerebellum, spine, kidney, adrenal gland and pancreas. Most VHL patients die from the consequences of cerebellar haemangioblastoma or renal cell carcinoma. The VHL gene is a tumour suppressor gene and is involved in angiogenesis by regulation of the activity of hypoxia-inducible factor 1-α (HIF1-α. Clinical diagnosis of VHL can be confirmed by molecular genetic analysis of the VHL gene, which is informative in virtually all VHL families. A patient with (suspicion for VHL is an indication for genetic counselling and periodical examination.

  7. Laser-cooling effects in few-ion clouds of Yb[sup +

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, C.S. (National Physical Lab., Teddington (United Kingdom)); Gill, P. (National Physical Lab., Teddington (United Kingdom)); Klein, H.A. (National Physical Lab., Teddington (United Kingdom)); Levick, A.P. (National Physical Lab., Teddington (United Kingdom)); Rowley, W.R.C. (National Physical Lab., Teddington (United Kingdom))

    1994-08-01

    We report some laser-cooling effects in a few [sup 172]Yb[sup +] ions held in a Paul trap. Pronounced cloud-to-crystal phase transitions have been observed as discontinuities in the Yb[sup +] fluorescence spectrum of the 369 nm cooling transition. The first reported two-dimensional images of Yb[sup +] clouds with evidence of crystal structure have been recorded using a photon-counting position-sensitive detector. An ion temperature of 100 mK has been estimated from the size of a single ion image. Stepwise cooling of a re-heated, few-ion Yb[sup +] cloud was also observed. (orig.)

  8. Laser-cooling effects in few-ion clouds of Yb+

    International Nuclear Information System (INIS)

    Edwards, C.S.; Gill, P.; Klein, H.A.; Levick, A.P.; Rowley, W.R.C.

    1994-01-01

    We report some laser-cooling effects in a few 172 Yb + ions held in a Paul trap. Pronounced cloud-to-crystal phase transitions have been observed as discontinuities in the Yb + fluorescence spectrum of the 369 nm cooling transition. The first reported two-dimensional images of Yb + clouds with evidence of crystal structure have been recorded using a photon-counting position-sensitive detector. An ion temperature of 100 mK has been estimated from the size of a single ion image. Stepwise cooling of a re-heated, few-ion Yb + cloud was also observed. (orig.)

  9. The Cold Shock Domain of YB-1 Segregates RNA from DNA by Non-Bonded Interactions.

    Directory of Open Access Journals (Sweden)

    Vladislav Kljashtorny

    Full Text Available The human YB-1 protein plays multiple cellular roles, of which many are dictated by its binding to RNA and DNA through its Cold Shock Domain (CSD. Using molecular dynamics simulation approaches validated by experimental assays, the YB1 CSD was found to interact with nucleic acids in a sequence-dependent manner and with a higher affinity for RNA than DNA. The binding properties of the YB1 CSD were close to those observed for the related bacterial Cold Shock Proteins (CSP, albeit some differences in sequence specificity. The results provide insights in the molecular mechanisms whereby YB-1 interacts with nucleic acids.

  10. Yb-based heavy fermion compounds and field tuned quantum chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Mun, Eundeok [Iowa State Univ., Ames, IA (United States)

    2010-01-01

    The motivation of this dissertation was to advance the study of Yb-based heavy fermion (HF) compounds especially ones related to quantum phase transitions. One of the topics of this work was the investigation of the interaction between the Kondo and crystalline electric field (CEF) energy scales in Yb-based HF systems by means of thermoelectric power (TEP) measurements. In these systems, the Kondo interaction and CEF excitations generally give rise to large anomalies such as maxima in ρ(T) and as minima in S(T). The TEP data were use to determine the evolution of Kondo and CEF energy scales upon varying transition metals for YbT2Zn20 (T = Fe, Ru, Os, Ir, Rh, and Co) compounds and applying magnetic fields for YbAgGe and YbPtBi. For YbT2Zn20 and YbPtBi, the Kondo and CEF energy scales could not be well separated in S(T), presumably because of small CEF level splittings. A similar effect was observed for the magnetic contribution to the resistivity. For YbAgGe, S(T) has been successfully applied to determine the Kondo and CEF energy scales due to the clear separation between the ground state and thermally excited CEF states. The Kondo temperature, TK, inferred from the local maximum in S(T), remains finite as magnetic field increases up to 140 kOe. In this dissertation we have examined the heavy quasi-particle behavior, found near the field tuned AFM quantum critical point (QCP), with YbAgGe and YbPtBi. Although the observed nFL behaviors in the vicinity of the QCP are different between YbAgGe and YbPtBi, the constructed H-T phase diagram including the two crossovers are similar. For both YbAgGe and YbPtBi, the details of the quantum criticality turn out to be complicated. We expect that YbPtBi will provide an additional example of field tuned quantum criticality, but clearly there are further experimental investigations left and more ideas needed to understand the basic physics of field-induced quantum

  11. Downconversion in Pr3+–Yb3+ co-doped ZBLA fluoride glasses

    International Nuclear Information System (INIS)

    Maalej, O.; Boulard, B.; Dieudonné, B.; Ferrari, M.; Dammak, M.; Dammak, M.

    2015-01-01

    Fluorozirconate ZBLA glasses with molar composition 57ZrF 4 –34BaF 2 –5LaF 3 –4AlF 3 –0.5PrF 3 –xYbF 3 (from x=0 to 10) were synthesized to evaluate the rate of the conversion of visible photons into infrared photons. The emission spectra in the near infrared (NIR) at 950–1100 nm and the luminescence decays in the visible and NIR indicate an energy transfer from Pr 3+ to Yb 3+ upon blue excitation of Pr 3+ at 440 nm. The energy transfer efficiency increases with Yb 3+ concentration to reach 86% with 0.5Pr 3+ –10Yb 3+ co-doping (in mol%). However, the quenching of the Yb 3+ emission strongly reduces the efficiency of the downconversion process: the decay time values decrease from 600 µs (x=0.5 mol%) to 85 µs (x=10 mol%). - Highlights: • We synthesized 0.5Pr 3+ –xYb 3+ co-doped ZBLA glasses (from x=0 to 10 mol %). • Photoluminescence of Yb 3+ was observed at 980 nm under blue excitation. • Time resolved measurements have been performed in the visible and near infrared. • Energy transfer efficiency from Pr 3+ to Yb 3+ reaches 86% in 0.5 Pr 3+ –10Yb 3+ glass

  12. Magnetic structure of the YbMn2SbBi compound

    International Nuclear Information System (INIS)

    Morozkin, A.V.; Manfrinetti, P.

    2011-01-01

    Graphical abstract: Display Omitted Research highlights: → A neutron diffraction investigation in zero applied field of La 2 O 2 S-type YbMn 2 SbBi shows antiferromagnetic ordering below 138(3) K and ferrimagnetic ordering below 112(3) K. → Between 138 and 112 K, the magnetic structure of YbMn 2 SbBi consists of antiferromagnetically coupled ab-plane magnetic moments of the manganese atoms (D 1d magnetic point group). → Below 112(3) K, the magnetic structure of YbMn 2 SbBi becames the sum antiferromagnetic component with D 1d magnetic point group and ferromagnetic one with C 2 magnetic point group. → The magnitude of Yb and Mn magnetic moments in YbMn 2 SbBi at 2 K (M Yb = 3.6(2) μ B , M Mn = 3.5(2) μ B ) correspond to the trivalent state of the Yb ions and tetravalent state of the Mn ions. - Abstract: A neutron diffraction investigation has been carried out on the trigonal La 2 O 2 S-type (hP5, space group P3-bar ml, No. 164; also CaAl 2 Si 2 -type) YbMn 2 SbBi intermetallic compound. The YbMn 2 SbBi presents antiferromagnetic ordering below 138(3) K and ferrimagnetic ordering below 112(3) K. Between 138 and 112 K, the magnetic structure of YbMn 2 SbBi consists of antiferromagnetically coupled ab-plane magnetic moments of the manganese atoms (D 1d magnetic point group). Below 112(3) K, the ferromagnetic components of Yb and Mn begin to develop, and the magnetic structure of YbMn 2 SbBi becames the sum antiferromagnetic component with D 1d magnetic point group and ferromagnetic one with C 2 magnetic point group. The magnitude of Yb and Mn magnetic moments in YbMn 2 SbBi at 2 K (M Yb = 3.6(2) μ B , M Mn = 3.5(2) μ B ) correspond to the trivalent state of the Yb ions and tetravalent state of the Mn ions.

  13. The recombination channels of luminescence excitation in YAG:Yb single crystalline films

    International Nuclear Information System (INIS)

    Zakharko, Ya.M.; Luchechko, A.P.; Ubizskii, S.B.; Syvorotka, I.I.; Martynyuk, N.V.; Syvorotka, I.M.

    2007-01-01

    Absorption and emission spectra, luminescence decay kinetics and thermostimulated luminescence of X-ray irradiated YAG:Yb single crystalline films were studied. Two emission bands peaked at 420 and 488 nm have been detected in the investigated films. The strong thermal quenching of luminescence band at 488 nm was observed above 160 K. The influence of growth conditions and annealing in air on the lifetime of Yb 3+ ion excited state in the IR spectral region have been revealed. The recombination mechanisms of the f-f transition at Yb 3+ ion excitation, as well as the mechanism of lifetime shortening for the excited Yb 3+ luminescence have been discussed

  14. Synthesis, properties, and crystal structure of complex Cp2Yb(DAD)

    International Nuclear Information System (INIS)

    Trifonov, A.A.; Kirillov, E.N.; Bochkarev, M.N.; Shumani, G.; Myule, S.

    1999-01-01

    Diazadiene complex of trivalent ytterbium Cp 2 Yb(DAD) (1) (DAD = Bu 1 -N CH-CH = N-Bu 1 ) was obtained by three routes: the oxidation of Cp 2 Yb(THF) 2 by diazadiene in tetrahydrofuran (THF), the reaction of Cp 2 YbCl with DAD 2- Na 2 + (2:1), and the reaction of Cp 2 YbCl(THF) with DAD - K + in the 1:1 ratio. Complex 1 was characterized by microanalysis, IR spectroscopy, magnetochemistry, and X-ray structural analysis [ru

  15. Influence of dopant concentration on spectroscopic properties of Sr2CeO4:Yb nanocrystals

    Science.gov (United States)

    Stefanski, M.; Kędziorski, A.; Hreniak, D.; Strek, W.

    2017-12-01

    Optical properties of Sr2CeO4:Yb nanocrystals synthesized via Pechini's method are reported. The samples were characterized by X-ray diffraction data measurements. The unit cell parameters were determined using Rietveld refinement. It was found that they decreased with increasing amount of Yb ions. The absorption, excitation, emission spectra and luminescence decay profiles of the Sr2CeO4:Yb nanocrystals were investigated. It was observed that optical properties were strongly dependent on Yb concentration. It was found that Yb3+-O2- charge transfer transitions have great influence on the absorption spectra. It can be seen in the emission spectra that in addition to standard bands/lines corresponding to Ce-O metal-to-ligand charge transfer of Sr2CeO4 and f-f transitions of Yb3+, there is emission band centered at 744 nm. Its intensity depends on the concentration of the dopant. Recorded decay times become shorter with increasing dopant concentration due to the Yb3+ concentration quenching. Excitation spectra indicate the energy transfer from Ce-O charge transfer states to Yb3+2F5/2 state. The issue of appearance of down-conversion process in Sr2CeO4:Yb nanocrystals is considered.

  16. Spectral properties of hydrothermally-grown Nd:LuAG, Yb:LuAG, and Yb:Lu{sub 2}O{sub 3} laser materials

    Energy Technology Data Exchange (ETDEWEB)

    Brown, David C., E-mail: DBrown@snakecreeklasers.com [Snake Creek Lasers LLC, Friendsville, PA 18818 (United States); McMillen, Colin D.; Moore, Cheryl; Kolis, Joseph W. [Department of Chemistry and Center for Optical Materials Science and Engineering Technologies, Clemson University, Clemson, SC 29634-0973 (United States); Envid, Victoria [Snake Creek Lasers LLC, Friendsville, PA 18818 (United States)

    2014-04-15

    We have investigated the hydrothermal growth of, and spectrally characterized, the lutetium based laser materials Nd:LuAG, Yb:LuAG, and Yb:Lu{sub 2}O{sub 3}. Absorption cross-section data are presented for Nd:LuAG at 83, 175, and 295 K. Absorption cross-section data was also obtained for Yb:LuAG at 83, 175, and 295 K; the 295 K data was used to generate emission cross-sections using the method of reciprocity. For Yb:Lu{sub 2}O{sub 3}, we present absorption cross-sections at 295 K as well as emission cross-sections derived using reciprocity. -- Highlights: • We present spectral properties for hydrothermally-grown laser crystals. • Absorption cross-section data are presented for Nd:LuAG and Yb:LuAG at 83, 175, and 295 K. • Emission cross-sections are presented for Yb:LuAG at 295 K derived by reciprocity. • We present absorption cross-sections at 295 K as well as emission cross-sections derived using reciprocity for the laser material Yb:Lu{sub 2}O{sub 3}.

  17. 'Obligate' anaerobic Salmonella strain YB1 suppresses liver tumor growth and metastasis in nude mice.

    Science.gov (United States)

    Li, Chang-Xian; Yu, Bin; Shi, Lei; Geng, Wei; Lin, Qiu-Bin; Ling, Chang-Chun; Yang, Mei; Ng, Kevin T P; Huang, Jian-Dong; Man, Kwan

    2017-01-01

    The antitumor properties of bacteria have been demonstrated over the past decades. However, the efficacy is limited and unclear. Furthermore, systemic infection remains a serious concern in bacteria treatment. In this study, the effect of YB1, a rationally designed 'obligate' anaerobic Salmonella typhimurium strain, on liver tumor growth and metastasis in a nude mouse orthotopic liver tumor model was investigated. The orthotopic liver tumor model was established in nude mice using the hepatocellular carcinoma cell line MHCC-97L. Two weeks after orthotopic liver tumor implantation, YB1, SL7207 and saline were respectively administered through the tail vein of the mice. Longitudinal monitoring of tumor growth and metastasis was performed using Xenogen IVIS, and direct measurements of tumor volume were taken 3 weeks after treatment. In vitro , MHCC-97L and PLC cells were incubated with YB1 or SL7207 under anaerobic conditions. YB1 was observed to invade tumor cells and induce tumor cell apoptosis and death. The results revealed that all mice in the YB1 group were alive 3 weeks after YB1 injection while all mice in the SL7207 group died within 11 days of the SL7207 injection. The body weight decreased by ~9% on day 1 after YB1 injection and but subsequently recovered. Liver tumor growth and metastases were significantly inhibited following YB1 treatment. By contrast to the control group, a large number of Gr1-positive cells were detected on days 1 to 21 following YB1 treatment. Furthermore, YB1 also effectively invaded tumor cells and induced tumor cell apoptosis and death. In conclusion, YB1 suppressed liver tumor growth and metastasis in a nude mice liver tumor model. The potential mechanism may be through enhancing innate immune response and inducing tumor cell apoptosis and cell death.

  18. Jacob Stael von Holstein ja palladionism eesti arhitektuuris / Ants Hein

    Index Scriptorium Estoniae

    Hein, Ants, 1952-

    2005-01-01

    Sõjaväeinsenerist ja arhitektist Jacob Stael von Holsteinist (1628, Pärnu-1679), tema kavandatud hoonetest ja rollist 17. sajandi II poole arhitektuuris. Fabian von Ferseni Toompeal Lossiplatsil asunud elamust (lammutati 1894) ja Maardu mõisahoonest, Hans von Ferseni Mäo mõisahoonest Järvamaal, Otto Wilhelm von Ferseni majast Toompeal, Axel von Roseni majast Tallinnas Pikk t. 28 (1670-74), Otto Reinhold von Taube majast Tartus (hävinud), J. S. von Holsteini enda hoonetest: majast Tallinnas Toompea 1, Anija mõisahoonest, elamust Riias jm. Bibliograafia lk. 452

  19. The von Meyenburg complex; Der von Meyenburg Komplex

    Energy Technology Data Exchange (ETDEWEB)

    Schwab, S.A.; Bautz, W.; Uder, M.; Kuefner, M.A. [Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. fuer Radiologie

    2008-07-01

    The von Meyenburg complex (VMC) describes bile duct hamartomas and presents a rare, benign incidental finding in liver imaging. We report on a 61-year-old man, who was referred for a follow up study 14 years after remission of Hodgkin's disease. Computed tomography (CT) revealed multiple hypodense lesions throughout the liver, primary suggesting recurrent Hodgkin's disease. Previous CT-examinations, which were obtained at a later date, showed those lesions in identical distribution and morphology over the years, leading to diagnosis of multiple bile duct hamartomas (VMC). Making imaging-based diagnosis of VMC including ultrasound, CT and magnetic resonance imaging is a challenging task for the radiologist. Based on literature research findings, the impact of different modalities in the diagnostic work-up of VMC is discussed. (orig.)

  20. Neues über das Tertiär von Java und die mesozoischen Schichten von West-Borneo

    NARCIS (Netherlands)

    Martin, K.

    1888-01-01

    Die Monographie, welche unter dem Titel Die Fossilien von Java herausgegeben wird ¹), ist so weit fortgeschritten, dass sich aus den in ihr beschriebenen Gastropoden bereits eine Anzahl von Schlussfolgerungen ableiten lässt, welche für die in Bearbeitung begriffene, geologische Karte von Java von

  1. Eine Analyse des Zusammenhangs zwischen dem Konsum von Alkopops und dem Problemverhalten von Jugendlichen

    OpenAIRE

    Metzner, Cornelia Beate Isabel

    2007-01-01

    Zielsetzung: In dieser Arbeit wird untersucht, ob bei Jugendlichen ein Zusammenhang zwischen dem Konsum von Alkopops einerseits und dem sonstigen Alkoholtrinkverhalten, dem Konsum von Zigaretten und illegalen Drogen sowie weiteren Risikoverhaltensweisen andererseits besteht, ferner ob sich Unterschiede im Verhalten von Jungen und Mädchen ergeben. Theoretischer und empirischer Hintergrund: �Alkopops�, d. h. Mischgetränke diverser Hersteller aus Likör bzw. Schnaps und Limonade sowie wein- ...

  2. Analytik von Minorlipiden: Ferulasäureester von Phytosterolen (gamma-Oryzanol) in Reis

    OpenAIRE

    Miller, Andreas

    2005-01-01

    Ferulasäureestern von Phytosterolen (γ-Oryzanol) werden antioxidative und cholesterinsenkende Eigenschaften zugeschrieben. Bisher beschriebene Methoden zur Analytik von γ-Oryzanol in Reis erforderten eine aufwendige Aufreinigung des Probenextrakts. In dieser Arbeit wurde basierend auf der on-line LC-GC eine Methode entwickelt, die die simultane Bestimmung von γ-Oryzanol-Gehalt und Sterylferulat-Verteilung ohne Aufreinigung des Probenextrakts erlaubt. Mit Hilfe der Technik wurden die natürlich...

  3. Redoxspeziation von endlagerrelevanten Elementen mit Hilfe von Trennmethoden gekoppelt an ein Massenspektrometer mit induktiv gekoppeltem Plasma

    OpenAIRE

    Graser, Carl-Heinrich

    2015-01-01

    Im Rahmen dieser Arbeit wurden Redoxspeziationsanalysen von Eisen, Neptunium und Plutonium per CE-SF-ICP-MS durchgeführt. Durch Optimierung der Trennparameter konnten Trennungen der Pu Oxidationsstufen III bis VI und Trennungen der Np Oxidationsstufen IV bis VI binnen 15 Minuten mit einer Nachweisgrenze von 10-12 M durchgeführt werden. Die Trennung der Fe Oxidationsstufen II und III gelang in weniger als 5 Minuten mit einer Nachweisgrenze von 5-10-8 M.

  4. Magnetocaloric effect in In doped YbMnO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Sattibabu, Bhumireddi, E-mail: bsb.satti@gmail.com [School of Engineering Sciences and Technology, University of Hyderabad, Hyderabad 500046 (India); Department of Electronics and Physics, Institute of Science, GITAM University, Visakhapatnam 530045 (India); Bhatnagar, A.K., E-mail: anilb42@gmail.com [School of Physics, University of Hyderabad, Hyderabad 500046 (India); Vinod, K.; Mani, Awadhesh [Condensed Matter Physics Division, Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India)

    2017-06-01

    Magnetic and magnetocaloric (MCE) properties of Yb{sub 0.9}In{sub 0.1}MnO{sub 3} and Yb{sub 0.8}In{sub 0.2}MnO{sub 3} polycrystalline samples are presented in this paper. Isothermal magnetization measurements reveal a field induced magnetic transition. Magnetic entropy change of 2.34±0.35 J/mole-K for Yb{sub 0.9}In{sub 0.1}MnO{sub 3} and 2.64±0.38 J/mole-K for Yb{sub 0.8}In{sub 0.2}MnO{sub 3} field change ΔH =10 KOe is observed around the ferromagnetic ordering temperature of Yb{sup 3+}. Values of relative cooling power for the same field change are found to be 38.03±9 J /mol, and 40.90±10 J/mol for Yb{sub 0.9}In{sub 0.1}MnO{sub 3} and Yb{sub 0.8}In{sub 0.2}MnO{sub 3}, respectively. These values suggest In doped YbMnO{sub 3} may be a potential candidate for magnetic refrigerant at low temperatures.

  5. Enhanced exciton emission from ZnO nano-phosphor induced by Yb3+ ions

    CSIR Research Space (South Africa)

    Kabongo, GL

    2014-01-01

    Full Text Available In this work, the sol–gel method was used to prepare Ytterbium (Yb(sup3+)) doped ZnO nano-phosphors with different concentrations of Yb(sup3+) ions. Their structural, morphological, photoluminescence, electronic states and the chemical composition...

  6. Preparation, Biological Evaluation and Dosimetry Studies of 175Yb-Bis-Phosphonates for Palliative Treatment of Bone Pain

    Directory of Open Access Journals (Sweden)

    Ashraf Fakhari

    2015-10-01

    Full Text Available Objective: Optimized production and quality control of ytterbium-175 (Yb-175 labeled pamidronate and alendronate complexes as efficient agents for bone pain palliation has been presented. Methods: Yb-175 labeled pamidronate and alendronate (175Yb-PMD and 175Yb-ALN complexes were prepared successfully at optimized conditions with acceptable radiochemical purity, stability and significant hydroxyapatite absorption. The biodistribution of complexes were evaluated up to 48 h, which demonstrated significant bone uptake ratios for 175Yb-PAM at all-time intervals. It was also detected that 175Yb-PAM mostly washed out and excreted through the kidneys. Results: The performance of 175Yb-PAM in an animal model was better or comparable to other 175Yb-bone seeking complexes previously reported. Conclusion: Based on calculations, the total body dose for 175Yb-ALN is 40% higher as compared to 175Yb-PAM (especially kidneys indicating that 175Yb-PAM is probably a safer agent than 175Yb-ALN.

  7. Structural specifics of the condensate prepared by thermal evaporation of alloys of As2S3-Yb systems

    International Nuclear Information System (INIS)

    Ehfendiev, Eh.G.; Mamedov, A.I.; Il'yasov, T.M.; Rustamov, P.G.

    1987-01-01

    The problem aimed at preparation of the films of As 2 S 3 -Yb system, at studying their substructure depending on condensation conditions and defining noncrystallinity region of this system in the film state, is formulated. It is shown that in representative samples of As 2 S 3 -Yb system the vitrification region is extended up to 7 at.% Yb, in the films noncrystallinity region is extended up to 30 at.% Yb. With up to 30 at.% increase of ytterbium amount in initial alloys a tendency to crystallization in amorphous condensate structure is noticed. In evaporation of As 2 S 3 + 40 at.% Yb and As 2 S 3 + 50 at.% Yb, unknown in the film state YbAs 2 S 4 , Yb 3 As 4 S 9 and YbAs 4 S 7 phases are prepared, and the latter is formed in case of As 2 S 3 + 50 at.% Yb alloy at small evaporation rates (∼10 A/s). Substructure of As 2 S 3 + 50 at.% Yb alloy prepared condensate is more dependent on evaporation rate than in evaporation of As 2 S 3 + 40 at.% Yb alloy. In this case, evaporation rates being ∼ 100 A/s, the condensate has a polycrystal structure, and at small rates of ∼ 10 A/c, condensate structure is primarily blocked

  8. THE DIGITAL VON FAHRENHEID PYRAMID

    Directory of Open Access Journals (Sweden)

    M. Bura

    2017-08-01

    Full Text Available 3D Scanners Lab from Digital Humanities Laboratory at the University of Warsaw initiated the scientific project, the purpose of which was to call attention to systematically penetrated and devastated pyramid-shaped tomb from the XVIII/XIX century, of family von Fahrenheid in Rapa in Banie Mazurskie commune (NE Poland. By conducting a series of non-invasive studies, such as 3D inventory using terrestrial laser scanning (TLS, thermal imaging, georadar measurements (around and inside the tomb and anthropological research of mummified remains as well - the complete dataset was collected. Through the integration of terrestrial (TLS and airborne laser scanning (ALS authors managed to analyse the surroundings of Fahrenheid pyriamid and influence of some objects (like trees on the condition and visibility of the Pyramids in the landscape.

  9. Optical waveguide formed in Yb:GdCOB and Yb:YCOB crystals by 3.0MeV O{sup +} implantation

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Yang, E-mail: sdujy@163.com [College of Physics and Electronics, Shandong Normal University, Jinan 250014 (China)

    2013-07-15

    Planar optical waveguides were formed in Yb:GdCOB and Yb:YCOB crystals by 3.0 MeV O{sup +} ion implantation at fluence of 2 × 10{sup 15} ions/cm{sup 2} at room temperature, respectively. The prism coupling method was performed to characterize the dark-mode property of the waveguides. The refractive index profiles in the waveguides were reconstructed by reflectivity calculation method (RCM). The results show that after the implantation, a 1.5 μm-wide region with enhanced refractive-index was formed beneath the sample surfaces to act as waveguide structures for both Yb:GdCOB and Yb:YCOB.

  10. Die Wirkung von Desacetylcefotaxin, einem Metaboliten von Cefotaxim, in vitro und auf die experimentelle Infektion mit Escherichia coli

    OpenAIRE

    Wirbelauer, J.; Hof, H.; Hacker, Jörg

    2009-01-01

    Die MHK-Werte von Desacetylcefotaxim gegen verschiedene, z. T. ampicillinresistente Stämme von Escherichia coH, die mit Hilfe einer Agardilutionsmethode erhoben wurden, waren höher als die von Cefotaxim und Ceftriaxon, jedoch niedriger als die von Cefoxitin. In einem Modell der systemischen Infektion der Maus mit einem plasmidtragenden, betalactamaseproduzierenden Stamm von E. coli führte die Therapie mit Desacetylcefotaxim zu einer starken Reduktion der Keime pro Leber. Im Vergleich zur Ther...

  11. Laser-diode pumped 40-W Yb:YAG ceramic laser.

    Science.gov (United States)

    Hao, Qiang; Li, Wenxue; Pan, Haifeng; Zhang, Xiaoyi; Jiang, Benxue; Pan, Yubai; Zeng, Heping

    2009-09-28

    We demonstrated a high-power continuous-wave (CW) polycrystalline Yb:YAG ceramic laser pumped by fiber-pigtailed laser diode at 968 nm with 400 mum fiber core. The Yb:YAG ceramic laser performance was compared for different Yb(3+) ion concentrations in the ceramics by using a conventional end-pump laser cavity consisting of two flat mirrors with output couplers of different transmissions. A CW laser output of 40 W average power with M(2) factor of 5.8 was obtained with 5 mol% Yb concentration under 120 W incident pump power. This is to the best of our knowledge the highest output power in end-pumped bulk Yb:YAG ceramic laser.

  12. Thermodynamic description of the Al-Cu-Yb ternary system supported by first-principles calculations

    Directory of Open Access Journals (Sweden)

    Huang G.

    2016-01-01

    Full Text Available Phase relationships of the ternary Al-Cu-Yb system have been assessed using a combination of CALPHAD method and first principles calculations. A self-consistent thermodynamic parameter was established based on the experimental and theoretical information. Most of the binary intermetallic phases, except Al3Yb, Al2Yb, Cu2Yb and Cu5Yb, were assumed to be zero solubility in the ternary system. Based on the experimental data, eight ternary intermetallic compounds were taken into consideration in this system. Among them, three were treated as line compounds with large homogeneity ranges for Al and Cu. The others were treated as stoichiometric compounds. The calculated phase diagrams were in agreement with available experimental and theoretical data.

  13. Simulation of 4f-5d transitions of Yb2+ in potassium and sodium halides

    International Nuclear Information System (INIS)

    Duan Changkui; Tanner, P A

    2008-01-01

    The free ion energy level parameters of Yb 2+ are obtained by fitting the 4f 13 5d Yb 2+ free ion energy levels. A model is proposed for scaling these parameters so that they are appropriate for Yb 2+ in crystals. Treating the scaling factor, the barycenter energy E exc of the 4f 13 5d configuration, and the crystal-field splitting parameter B 4 (dd) as free parameters and adopting the 4f crystal-field parameters of the 4f 13 configuration Yb 3+ ion in other hosts with the same ligands, the absorption spectra of Yb 2+ in MX (M = K, Na; X = F, Cl, Br, I) hosts are well simulated. A model is proposed for taking the effect of charge compensation into account and this shows that the inclusion of charge compensation effects does not significantly alter the calculated electronic absorption spectra but may considerably change the dynamics of the system

  14. Improving the photoluminescence response of Er-Tm: Al2O3 films by Yb codoping

    International Nuclear Information System (INIS)

    Xiao Zhisong; Serna, R.; Afonso, C.N.; Cheng Guoan; Vickridge, I.

    2007-01-01

    Amorphous Al 2 O 3 films doped with Er, Tm and Yb have been prepared by pulsed laser deposition. A broadband emission in the range 1400-1700 nm with two peaks around 1540 and 1640 nm has been observed, both in the Er-Tm and Er-Tm-Yb codoped films. The Tm-related photoluminescence (PL) intensity at 1640 nm is enhanced when codoping with Yb thus suggesting the existence of multiple energy transfer processes from Yb to Er and Er to Tm. The Er-Tm-Yb codoped film exhibits a broadband emission with a full-width half-maximum of 184 nm similar to that of the film codoped with Tm and Er but having higher Tm to Er concentration ratio and higher PL lifetime values

  15. Growth and luminescent properties of Yb3+--doped oxide single crystals for scintillator application

    International Nuclear Information System (INIS)

    Yoshikawa, A.; Ogino, H.; Shim, J.B.; Nikl, M.; Solovieva, N.; Fukuda, T.

    2004-01-01

    Rod-shaped (Lu 1-x Yb x ) 3 Al 5 O 12 with x=0.05, 0.15, 0.30 and (Y 1-x Yb x )AlO 3 with x=0.05, 0.10, 0.30 single crystals were grown by the micro-pulling-down method. Edge-defined film-fed growth method was used to prepare (Y 0.9 Yb 0.1 )VO 4 crystal, while Ca 8 (La 1.98 Yb 0.02 )(PO 4 ) 6 O 2 crystal was grown by the Czochralski method. Luminescence of these crystals was studied with main attention paid to the charge transfer emission of Yb 3+ . Temperature tuned decay times in the time scale of units--tens of nanosecond was measured as a feature possibly interesting for an application in scintillation detectors in positron emission tomography

  16. Synthesis and Downconversion Emission Property of Yb2O3:Eu3+ Nanosheets and Nanotubes

    Directory of Open Access Journals (Sweden)

    Chao Qian

    2013-01-01

    Full Text Available Ytterbium oxide (Yb2O3 nanocrystals with different Eu3+ (1%, 2%, 5%, and 10% doped concentrations were synthesized by a facile hydrothermal method, subsequently by calcination at 700°C. The crystal phase, size, and morphology of prepared samples were characterized by X-ray diffraction (XRD and transmission electron microscopy (TEM. The results show that the as-prepared Yb2O3 nanocrystals with sheet- and tube-like shape have cubic phase structure. The Eu3+ doped Yb2O3 nanocrystals were revealed to have good down conversion (DC property and intensity of the DC luminescence can be modified by Eu3+ contents. In our experiment the 1% Eu3+ doped Yb2O3 nanocrystals showed the strongest DC luminescence among the obtained Yb2O3 nanocrystals.

  17. Spectroscopic properties and energy levels of Yb{sup 3+} ion in huntite structure

    Energy Technology Data Exchange (ETDEWEB)

    Malakhovskii, A.V. [L.V. Kirensky Institute of Physics, Siberian Branch Russian Academy of Sciences, 660036 Krasnoyarsk (Russian Federation)], E-mail: malakha@iph.krasn.ru; Sukhachev, A.L. [L.V. Kirensky Institute of Physics, Siberian Branch Russian Academy of Sciences, 660036 Krasnoyarsk (Russian Federation); Gnatchenko, S.L.; Kachur, I.S.; Piryatinskaya, V.G. [B. Verkin Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine, 61103 Kharkov (Ukraine); Temerov, V.L.; Krylov, A.S.; Edelman, I.S. [L.V. Kirensky Institute of Physics, Siberian Branch Russian Academy of Sciences, 660036 Krasnoyarsk (Russian Federation)

    2009-05-12

    Temperature dependence of Yb{sup 3+} optical absorption spectrum has been studied in crystals Yb{sub x}Tm{sub 1-x}Al{sub 3}(BO{sub 3}){sub 4} (x = 0.1, 0.2 and 1) in the temperature range 1.7-293 K. The spectra of the crystals appeared to be practically identical for the studied ytterbium concentrations. Raman scattering spectrum of YbAl{sub 3}(BO{sub 3}){sub 4} crystal has been measured. Group theory analysis of the optical absorption spectra is made, and new energy structure of the ground and excited states of Yb{sup 3+} ion, based on the experimental data obtained, is presented. Transformation of the local environment of Yb{sup 3+} ion depending on temperature has been found out. Spectrum of luminescence has been calculated from the absorption spectrum by reciprocity method with the use of the proposed energy structure.

  18. Cooperative emission in ion implanted Yb:YAG waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, G V; Desirena, H; De la Rosa, E [Centro de Investigaciones en Optica, Loma del Bosque 115, Lomas del Campestre, 37150 Leon, Guanajuato (Mexico); Flores-Romero, E; Rickards, J; Trejo-Luna, R [Instituto de Fisica, UNAM, Apartado Postal 20364, 01000 Mexico, D. F. (Mexico); Marquez, H, E-mail: gvvazquez@cio.mx [Departamento de Optica, CICESE, Km 107 Carr. Tijuana-Ensenada, 22860 Ensenada, B. C. (Mexico)

    2011-01-01

    In this work, we report the analysis of spectroscopic properties of waveguides fabricated by ion implantation in YAG doped with Yb{sup 3+} ions. Three emission bands were detected in the blue, green and red regions under 970-nm excitation. The strong blue-green emission can be explained by a cooperative process between ytterbium ion pairs, leading to emission centered at 514 nm. The additional blue bands as well as green and red emission bands are attributed to the presence of Tm{sup 3+} and Er{sup 3+} traces. The results include absorption and emission curves as well as decay time rates.

  19. Cooperative emission in ion implanted Yb:YAG waveguides

    International Nuclear Information System (INIS)

    Vazquez, G V; Desirena, H; De la Rosa, E; Flores-Romero, E; Rickards, J; Trejo-Luna, R; Marquez, H

    2011-01-01

    In this work, we report the analysis of spectroscopic properties of waveguides fabricated by ion implantation in YAG doped with Yb 3+ ions. Three emission bands were detected in the blue, green and red regions under 970-nm excitation. The strong blue-green emission can be explained by a cooperative process between ytterbium ion pairs, leading to emission centered at 514 nm. The additional blue bands as well as green and red emission bands are attributed to the presence of Tm 3+ and Er 3+ traces. The results include absorption and emission curves as well as decay time rates.

  20. VON WISPR Family Processors: Volume 1

    National Research Council Canada - National Science Library

    Wagstaff, Ronald

    1997-01-01

    ...) and the background noise they are embedded in. Processors utilizing those fluctuations such as the von WISPR Family Processors discussed herein, are methods or algorithms that preferentially attenuate the fluctuating signals and noise...

  1. Von Onlineplattformen und mittelalterlichen Märkten

    Directory of Open Access Journals (Sweden)

    Claudius Gräbner

    2017-12-01

    Full Text Available Mit der zunehmenden Digitalisierung und Vernetzung ökonomischer Systeme haben plattformbasierte Interaktionsbeziehungen stark an Bedeutung gewonnen. Hier werden zwei oder mehr Nutzungsgruppen durch eine dritte Seite, die Plattform, zusammengebracht. Die Interaktion wird in solchen zweiseitigen Märkten von den Plattformbetreibern kontrolliert. Kreditkartensysteme, Softwaremärkte oder werbefinanzierte Online-Communities stellen typische Beispiele dar. Da die Analyse von zweiseitigen Märkten mit Gleichgewichtsmodellen aufgrund der algebraischen Struktur des Problems in der Regel nicht praktikabel ist, präsentieren wir im vorliegenden Beitrag ein agentenbasiertes Modell, welches in einem kürzlich erschienenen Artikel ausführlicher diskutiert wird. Anhand von illustrativen Beispielen verdeutlichen wir die Implikationen eines agentenbasierten Ansatzes für die Innovationsökonomik im Allgemeinen und das Studium von Technologieentwicklung im Besonderen.

  2. Johann Friedrich Wilhelm Adolf von Baeyer

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 6. Johann Friedrich Wilhelm Adolf von Baeyer: A Pioneer of Synthetic Organic Chemistry. Gopalpur Nagendrappa. General Article Volume 19 Issue 6 June 2014 pp 489-522 ...

  3. Titanisierung von Implantatoberflächen

    Science.gov (United States)

    Zimmermann, Hanngörg; Heinlein, Markus; Guldner, Norbert W.

    Titan gilt seit Jahrzehnten als einer der wichtigsten Implantatwerkstoffe in der Medizin. Neben den guten mechanischen Eigenschaften (Leichtigkeit, hohe Festigkeit etc.), besitzen Titanimplantate vor allem eine hervorragende Körperverträglichkeit, so dass die Implantate optimal in den humanen Organismus integriert werden [1]. Ist jedoch aufgrund der Anforderungen an das Implantat eine hohe Flexibilität und/ oder Elastizität gefragt, so scheidet der Werkstoff Titan aufgrund seiner spröden und unflexiblen Materialeigenschaften aus. Die Folge ist der Einsatz von Implantatmaterialien, sowohl künstlichen als auch biologischen Ursprungs, welche nicht selten eine unzureichende Biokompatibilität aufweisen und somit zu Fremdköper- und immunologischen Reaktionen und Einkapselung des Implantates führen können. Die Erhöhung der Körperverträglichkeit, eine Adaption an das biologische Umfeld und eine hohe Biokompatibilität sind demzufolge die wichtigsten Eigenschaften bei der bedarfsgerechten Herstellung von Implantaten und Implantatoberflächen. Zur Gestaltung von innovativen, biokompatiblen Oberflächen stehen unterschiedliche technische Lösungsansätze zur Verfügung. Zum einen besteht die Möglichkeit, geeignete Oberflächeneigenschaften aus dem Grundmaterial selbst zu optimieren. Dies geschieht unter anderem durch Modifikation der Werkstoffoberflächen in Form von Texturierungen und Oberflächenrauhigkeiten. Zum anderen können die Oberflächeneigenschaften unabhängig von denen des Trägermaterials gestaltet werden. Durch Funktionalisierung der Oberflächen mit geeigneten Beschichtungen oder der Zugabe von Medikamenten (Drug Eluting) werden die Kunststoffimplantate dahingehend verändert, dass eine Steigerung der Körperakzeptanz erreicht wird. Die Titanbeschichtung von Implantatoberflächen kombiniert die positiven Materialeigenschaften von Titan und Polymer.

  4. 50th birthday of Christian von Ferber

    Directory of Open Access Journals (Sweden)

    2011-06-01

    Full Text Available On May 15, 2011 Christian von Ferber - member of the Editorial Board of "Condensed Matter Physics" and renowned expert in the fields of soft matter physics and complex systems - celebrated his 50th birthday. The Editorial board of CMP, colleagues and friends warmy congratulate Christian von Ferber and wish him and his family continuing good health and to enjoy many adventures and discoveries in his future scientific travels!

  5. The classification problem for von Neumann factors

    DEFF Research Database (Denmark)

    Sasyk, R.; Törnquist, Asger Dag

    2009-01-01

    We prove that it is not possible to classify separable von Neumann factors of types II, II or III, 0 ≤ λ ≤ 1, up to isomorphism by a Borel measurable assignment of "countable structures" as invariants. In particular the isomorphism relation of type II factors is not smooth. We also prove...... that the isomorphism relation for von Neumann II factors is analytic, but is not Borel....

  6. Hullud päevad von Krahlis

    Index Scriptorium Estoniae

    2006-01-01

    Von Krahli Teatris mängitakse neil päevi neli korda Peeter Jalaka lavastuses Tõnu Kõrvitsa kammeroopereid "Tuliaed" ja "Mu luiged, mu mõtted", mille aluseks on luuletaja Marie Heibergi saatus. Libreto autor on Maarja Kangro. Kammerooperid tulevad lavale Von Krahli Teatri ja Nargen Opera koostöös. Esitavad Kädy Plaas, Helen Lokuta, Nargen Opera koor ja Tallinna Kammerorkester, dirigent Tõnu Kaljuste

  7. Bedeutung von Umwelt- und Organismusfaktoren bei Autoaggressionen

    OpenAIRE

    Rohmann, Ulrich H.; Elbing, Ulrich; Hartmann, Hellmut

    1988-01-01

    In der vorliegenden Arbeit werden übergeordnete Hypothesen zu autoaggressiven Verhaltensweisen formuliert, wobei prozeßhafte Abläufe von umweltbezogenen und organischen Variablen angenommen werden. Eine solche dynamische Beziehung hat ihre Bedeutung sowohl für verursachende als auch aufrechterhaltende Faktoren. In einer Querschnittuntersuchung lassen sich Korrelationen von Tageszeit- und Tätigkeitscharakteristiken (umweltbezogene Variablen) zur Autoaggressionshäufigkeit und Pulsfrequenz (Orga...

  8. Visualisierung von typisierten Links in Linked Data

    Directory of Open Access Journals (Sweden)

    Georg Neubauer

    2017-09-01

    Full Text Available Das Themengebiet der Arbeit behandelt Visualisierungen von typisierten Links in Linked Data. Die wissenschaftlichen Gebiete, die im Allgemeinen den Inhalt des Beitrags abgrenzen, sind das Semantic Web, das Web of Data und Informationsvisualisierung. Das Semantic Web, das von Tim Berners Lee 2001 erfunden wurde, stellt eine Erweiterung zum World Wide Web (Web 2.0 dar. Aktuelle Forschungen beziehen sich auf die Verknüpfbarkeit von Informationen im World Wide Web. Um es zu ermöglichen, solche Verbindungen wahrnehmen und verarbeiten zu können sind Visualisierungen die wichtigsten Anforderungen als Hauptteil der Datenverarbeitung. Im Zusammenhang mit dem Sematic Web werden Repräsentationen von zuhammenhängenden Informationen anhand von Graphen gehandhabt. Der Grund des Entstehens dieser Arbeit ist in erster Linie die Beschreibung der Gestaltung von Linked Data-Visualisierungskonzepten, deren Prinzipien im Rahmen einer theoretischen Annäherung eingeführt werden. Anhand des Kontexts führt eine schrittweise Erweiterung der Informationen mit dem Ziel, praktische Richtlinien anzubieten, zur Vernetzung dieser ausgearbeiteten Gestaltungsrichtlinien. Indem die Entwürfe zweier alternativer Visualisierungen einer standardisierten Webapplikation beschrieben werden, die Linked Data als Netzwerk visualisiert, konnte ein Test durchgeführt werden, der deren Kompatibilität zum Inhalt hatte. Der praktische Teil behandelt daher die Designphase, die Resultate, und zukünftige Anforderungen des Projektes, die durch die Testung ausgearbeitet wurden.

  9. Synthesis and characterization of (Ba,Yb doped ceria nanopowders

    Directory of Open Access Journals (Sweden)

    Branko Matović

    2011-06-01

    Full Text Available Nanometric size (Ba, Yb doped ceria powders with fluorite-type structure were obtained by applying selfpropagating room temperature methods. Tailored composition was: Ce0.95−xBa0.05YbxO2−δ with fixed amount of Ba − 0.05 and varying Yb content “x” from 0.05 to 0.2. Powder properties such as crystallite and particle size and lattice parameters have been studied. Röntgen diffraction analyses (XRD were used to characterize the samples at room temperature. Also, high temperature treatment (up to 1550°C was used to follow stability of solid solutions. The mean diameters of the nanocrystals are determined from the full width at half maxima (FWHM of the XRD peaks. It was found that average diameter of crystallites is less than 3 nm. WilliamsonHall plots were used to separate the effect of the size and strain in the nanocrystals.

  10. High temperature luminescence of ZnSe:Yb crystals

    Directory of Open Access Journals (Sweden)

    Makhniy V. P.

    2016-05-01

    Full Text Available The problem of obtaining of effective edge luminescence with high temperature stability in the zinc selenide crystals is discussed. This task is solved by using as the dopant rare-earth element yttrium, which is introduced into the undoped ZnSe crystal by diffusion method. Doping was carried out in an evacuated to 10 -4 Torr. and a sealed quartz ampoule, in the opposite ends of which is a sample and a mixture of the crushed Yb and Se. It has been found that the diffusion coefficient of yttrium at a temperature of 1400 K is about 5⋅10 -7 cm 2/sec. It is shown that in the luminescence spectra of ZnSe:Yb samples in the temperature range 295-470 K only blue band is observed. Dependencies of parameters of this band from the excitation level are typical for the annihilation of excitons at their inelastic scattering by free carriers. The efficacy of blue radiation at 300 K is about 30% and does not fall more than twice with increasing temperature up to 470 K, indicating its high thermal stability.

  11. Low-temperature phase diagram of YbBiPt

    International Nuclear Information System (INIS)

    Movshovich, R.; Lacerda, A.; Canfield, P.C.; Thompson, J.D.; Fisk, Z.

    1994-01-01

    Resistivity measurements are reported on the cubic heavy-fermion compound YbBiPt at ambient and hydrostatic pressures to ∼19 kbar and in magnetic fields to 1 T. The phase transition at T c =0.4 K is identified by a sharp rise in resistivity. That feature is used to build low-temperature H-T and P-T phase diagrams. The phase boundary in the H-T plane follows the weak-coupling BCS expression remarkably well from T c to T c /4, while small hydrostatic pressure of ∼1 kbar suppresses the low-temperature phase entirely. These effects of hydrostatic pressure and magnetic field on the phase transition are consistent with an spin-density-wave (SDW) formation in a very heavy electron band at T=0.4 K. Outside of the SDW phase at low temperature, hydrostatic pressure increases the T 2 coefficient of resistivity, signaling an increase in heavy-fermion correlations with hydrostatic pressure. The residual resistivity decreases with pressure, contrary to trends in other Yb heavy-fermion compounds

  12. GHz Yb:KYW oscillators in time-resolved spectroscopy

    Science.gov (United States)

    Li, Changxiu; Krauß, Nico; Schäfer, Gerhard; Ebner, Lukas; Kliebisch, Oliver; Schmidt, Johannes; Winnerl, Stephan; Hettich, Mike; Dekorsy, Thomas

    2018-02-01

    A high-speed asynchronous optical sampling system (ASOPS) based on Yb:KYW oscillators with 1-GHz repetition rate is reported. Two frequency-offset-stabilized diode-pumped Yb:KYW oscillators are employed as pump and probe source, respectively. The temporal resolution of this system within 1-ns time window is limited to 500 fs and the noise floor around 10-6 (ΔR/R) close to the shot-noise level is obtained within an acquisition time of a few seconds. Coherent acoustic phonons are investigated by measuring multilayer semiconductor structures with multiple quantum wells and aluminum/silicon membranes in this ASOPS system. A wavepacket-like phonon sequence at 360 GHz range is detected in the semiconductor structures and a decaying sequence of acoustic oscillations up to 200 GHz is obtained in the aluminum/silicon membranes. Coherent acoustic phonons generated from semiconductor structures are further manipulated by a double pump scheme through pump time delay control.

  13. Yb-doped aluminophosphosilicate ternary fiber with high efficiency and excellent laser stability

    Science.gov (United States)

    Li, Yuwei; Peng, Kun; Zhan, Huan; Liu, Shuang; Ni, Li; Wang, Yuying; Yu, Juan; Wang, Xiaolong; Wang, Jianjun; Jing, Feng; Lin, Aoxiang

    2018-03-01

    By using chelate precursor doping technique and traditional modified chemical vapor deposition system, we fabricated Yb-doped aluminophosphosilicate (Al2O3-P2O5-SiO2, ternary Yb-APS) large-mode-area fiber and reported on its laser performance. The fiber preform was doped with Al, P and Yb with concentration of ∼8000 ppm, ∼1700 ppm and ∼400 ppm in molar percent, respectively. Tested with master oscillator power amplifier system, the home-made Yb-APS fiber was found to present 1.02 kW at 1061.1 nm with a high slope efficiency of 81.2% and excellent laser stability with power fluctuation less than ±1.1% for over 10 h. Compared with Yb-doped aluminosilicate (Al2O3-SiO2, binary Yb-AS) fiber, the introduction of P2O5 effectively suppressed photodarkening effect even the P/Al ratio is much less than 1, indicating that Yb-APS fiber is a better candidate for high power fiber lasers.

  14. Yb5Ni4Sn10 and Yb7Ni4Sn13: New polar intermetallics with 3D framework structures

    International Nuclear Information System (INIS)

    Lei Xiaowu; Sun Zhongming; Li Longhua; Zhong Guohua; Hu Chunli; Mao Jianggao

    2010-01-01

    The title compounds have been obtained by solid state reactions of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction studies. Yb 5 Ni 4 Sn 10 adopts the Sc 5 Co 4 Si 10 structure type and crystallizes in the tetragonal space group P4/mbm (No. 127) with cell parameters of a=13.785(4) A, c=4.492 (2) A, V=853.7(5) A 3 , and Z=2. Yb 7 Ni 4 Sn 13 is isostructural with Yb 7 Co 4 InGe 12 and crystallizes in the tetragonal space group P4/m (No. 83) with cell parameters of a=11.1429(6) A, c=4.5318(4) A, V=562.69(7) A 3 , and Z=1. Both structures feature three-dimensional (3D) frameworks based on three different types of one-dimensional (1D) channels, which are occupied by the Yb atoms. Electronic structure calculations based on density functional theory (DFT) indicate that both compounds are metallic. These results are in agreement with those from temperature-dependent resistivity and magnetic susceptibility measurements. - Graphical abstract: Two new ytterbium nickel stannides, namely, Yb 5 Ni 4 Sn 10 and Yb 7 Ni 4 Sn 13 , have been synthesized and structurally characterized by single-crystal X-ray diffraction studies. Both their structures feature three-dimensional (3D) frameworks based on three different types of one-dimensional (1D) channels, which are situated by all the Yb atoms. Electronic structure calculations based on density functional theory (DFT) indicate that both compounds are metallic, which are in accordance with the results from temperature-dependent resistivity and magnetic susceptibility measurements.

  15. Study of the production of {sup 177}Lu through {sup 176}Yb (n, {gamma}) {sup 177}Yb {yields} {sup 177}Lu nuclear reaction

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Giovana Pasqualini da; Osso Junior, Joao Alberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: gpsilva@ipen.br; jaosso@ipen.br

    2007-07-01

    The beta minus emitter {sup 177}Lu is a promising therapeutic radioisotope for the curative treatment of cancer using labelled proteins. It has a half - life of T{sub 1/2} = 6.71 day and maximum and average {beta}{sup -} energies of 421 and 133 keV, resulting in a short range of radiation in tissue. The decay is accompanied by the emission of low energy {gamma}-radiation with 208.3 keV (11%) and 113 keV (6.4%) suitable for simultaneous imaging, {sup 177}Lu can be produced by two different routes, namely, by irradiation of natural Lu{sub 2}O{sub 3} target ({sup 176}Lu, 2.6%) or enriched (in {sup 176}Lu) Lu{sub 2}O{sub 3} target, as also by irradiation of Yb target (Yb{sub 2}O{sub 3}) followed by radiochemical separation of {sup 177}Lu from Yb isotopes. The objective of this work is to study the production of {sup 177}Lu through the indirect {sup 176}Yb(n,{gamma}){sup 177}Yb {yields} {sup 177}Lu nuclear reaction. The results of the production yield of {sup 177}Lu will be shown and compared with the direct reaction. The method of choice for the chemical separation between Lu and Yb was the ion exchange, using an cation exchange resin in Cl{sup -} form and {alpha}-HIBA as eluent. Preliminary results showed a good separation of {sup 177}Lu from Yb{sub 2}O{sub 3} indirect targets. (author)

  16. Local Laser Cooling of Yb:YLF to 110 K

    Science.gov (United States)

    2011-09-01

    cooling model and was made possible by employing a novel and sensitive implementation of differential luminescence thermometry using balanced photo...Pringsheim, “Zwei bemerkungen uber den unterschied von lumineszenz- und temperaturstrahlung,” Z. Phys. 57(11-12), 739–746 (1929). 2. M. Sheik-Bahae and...and sensitive implementation of differential luminescence thermometry using balanced photo-detectors. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION

  17. Local structure investigation of Ga and Yb dopants in Co4Sb12 skutterudites

    Science.gov (United States)

    Hu, Yanyun; Chen, Ning; Clancy, J. P.; Salvador, James R.; Kim, Chang-Yong; Shi, Xiaoya; Li, Qiang; Kim, Young-June

    2017-12-01

    We report comprehensive x-ray absorption spectroscopy studies at both the Ga K edge and Yb L2 edge to elucidate the local structure of Ga and Yb dopants in YbxGayCo4Sb12 . Our extended x-ray absorption fine structure (EXAFS) data confirm that Ga atoms occupy two crystallographic sites: one is the 24 g site replacing Sb, and the other is the 2 a site in the off-center void position. We find that the occupancy ratio of these two sites varies significantly as a function of the filling fraction of additional Yb, which exclusively occupies the 2 a on-center site. At low concentrations of Yb, Ga24 g and Ga2 a dopants coexist and they form a charge-compensated compound defect proposed by Qiu et al. [Adv. Funct. Mater. 23, 3194 (2013), 10.1002/adfm.201202571]. The Ga24 g occupancy increases gradually with increasing Yb concentration, and almost all Ga occupies the 24 g site for the highest Yb concentration studied (x =0.4 ). In addition to the local structural evidence provided by our EXAFS data, we also present x-ray absorption near-edge structure (XANES) spectra, which show a small Ga K -edge energy shift as a function of Yb concentration consistent with the change from predominantly Ga2 a to Ga24 g states. Our result suggests that the increased solubility of Yb in Yb-Ga co-doped Co4Sb12 skutterudites is due to the increased Ga24 g electron acceptor, and thus provides an important strategy to optimize the carrier concentration in partially filled skutterudites.

  18. Coulomb-nuclear interference measurements of hexadecapole deformations in 168Yb and 178,180Hf

    International Nuclear Information System (INIS)

    Nettles, W.G.; Mississippi Coll., Clinton; Ramayya, A.V.; Hamilton, J.H.

    1988-01-01

    Coulomb-nuclear interference studies of 168 Yb and 178,180 Hf have been carried out with alpha particles from the Pittsburgh tandem. From coupled channel fits to the data at 18 MeV for 168 Yb and 19.5 MeV for 178,180 Hf, β 4 c values of -0.030(20), -0.166(18), and -0.180(6) were obtained, respectively. These data agree with the positive M 04 value from sub-Coulomb studies of 168 Yb but with the large negative M 04 values from sub-Coulomb studies of 178,180 Hf. (author)

  19. Y-box-binding protein-1 (YB-1) promotes cell proliferation, adhesion and drug resistance in diffuse large B-cell lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Xiaobing; Wu, Yaxun [Department of Pathology, Affiliated Cancer Hospital of Nantong University, Nantong 226361, Jiangsu (China); Wang, Yuchan [Department of Pathogen, Medical College, Nantong University, Nantong 226001, Jiangsu (China); Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226001, Jiangsu (China); Zhu, Xinghua; Yin, Haibing [Department of Pathology, Affiliated Cancer Hospital of Nantong University, Nantong 226361, Jiangsu (China); He, Yunhua [Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226001, Jiangsu (China); Li, Chunsun; Liu, Yushan; Lu, Xiaoyun; Chen, Yali; Shen, Rong [Department of Pathology, Affiliated Cancer Hospital of Nantong University, Nantong 226361, Jiangsu (China); Xu, Xiaohong, E-mail: xuxiaohongnantong@126.com [Department of Oncology, Affiliated Cancer Hospital of Nantong University, Nantong 226361, Jiangsu (China); He, Song, E-mail: hesongnt@126.com [Department of Pathology, Affiliated Cancer Hospital of Nantong University, Nantong 226361, Jiangsu (China)

    2016-08-15

    YB-1 is a multifunctional protein, which has been shown to correlate with resistance to treatment of various tumor types. This study investigated the expression and biologic function of YB-1 in diffuse large B-cell lymphoma (DLBCL). Immunohistochemical analysis showed that the expression statuses of YB-1 and pYB-1{sup S102} were reversely correlated with the clinical outcomes of DLBCL patients. In addition, we found that YB-1 could promote the proliferation of DLBCL cells by accelerating the G1/S transition. Ectopic expression of YB-1 could markedly increase the expression of cell cycle regulators cyclin D1 and cyclin E. Furthermore, we found that adhesion of DLBCL cells to fibronectin (FN) could increase YB-1 phosphorylation at Ser102 and pYB-1{sup S102} nuclear translocation. In addition, overexpression of YB-1 could increase the adhesion of DLBCL cells to FN. Intriguingly, we found that YB-1 overexpression could confer drug resistance through cell-adhesion dependent and independent mechanisms in DLBCL. Silencing of YB-1 could sensitize DLBCL cells to mitoxantrone and overcome cell adhesion-mediated drug resistance (CAM-DR) phenotype in an AKT-dependent manner. - Highlights: • The expression statuses of YB-1 and pYB-1{sup S102} are reversely correlated with outcomes of DLBCL patients. • YB-1 promotes cell proliferation by accelerating G1/S transition in DLBCL. • YB-1 confers drug resistance to mitoxantrone in DLBCL.

  20. Production and spectroscopy of ultracold YbRb{sup *} molecules

    Energy Technology Data Exchange (ETDEWEB)

    Nemitz, Nils

    2008-11-15

    This thesis describes the formation of electronically excited but translationally cold molecules formed from rubidium atoms and two isotopes of ytterbium ({sup 176}Yb and {sup 174}Yb) by means of photoassociation. The experiments were performed in a combined MOT with 10{sup 9} rubidium atoms and 2.10{sup 6} ytterbium atoms at temperatures of less than 1 mK. Photoassociation lines were found by trap loss spectroscopy throughout a wavelength range of 2 nm near the 795 nm D1 transition in rubidium. The majority of lines belong to two vibrational series in the excited YbRb{sup *} molecule, converging on a system of a ground state ytterbium atom and an excited rubidium atom. The strong variation of line strength between different vibrational lines is explained through the Franck-Condon principle. An improved version of the Leroy-Bernstein equation was used to extract the leading dispersion coefficient of the potential from the vibrational progression. Most of the observed lines show a resolved rotational structure as expected from a basic quantum mechanical model. The series terminates with the third or forth rotational component due to the ground state centrifugal barrier.The measured rotational constants agree very well with calculations based on the C{sub 6} coefficient. The discovery of a splitting of the rotational components into subcomponents indicates an uncommon angular momentum coupling described by Hund's case. Variations in the depth of the subcomponents indicates a similar splitting in the ground state, with the energies of the substates based on the alignment of the rubidium atom's magnetic dipole moment relative to the angular momentum carried by an approaching ytterbium atom. This creates an additional ground state barrier, partially suppressing some of the subcomponents. Using a rate equation model developed for this purpose, a maximum formation rate of 2.5.10{sup 6} molecules per second was calculated over the volume of the entire trap. The

  1. Production and spectroscopy of ultracold YbRb* molecules

    International Nuclear Information System (INIS)

    Nemitz, Nils

    2008-11-01

    This thesis describes the formation of electronically excited but translationally cold molecules formed from rubidium atoms and two isotopes of ytterbium ( 176 Yb and 174 Yb) by means of photoassociation. The experiments were performed in a combined MOT with 10 9 rubidium atoms and 2.10 6 ytterbium atoms at temperatures of less than 1 mK. Photoassociation lines were found by trap loss spectroscopy throughout a wavelength range of 2 nm near the 795 nm D1 transition in rubidium. The majority of lines belong to two vibrational series in the excited YbRb * molecule, converging on a system of a ground state ytterbium atom and an excited rubidium atom. The strong variation of line strength between different vibrational lines is explained through the Franck-Condon principle. An improved version of the Leroy-Bernstein equation was used to extract the leading dispersion coefficient of the potential from the vibrational progression. Most of the observed lines show a resolved rotational structure as expected from a basic quantum mechanical model. The series terminates with the third or forth rotational component due to the ground state centrifugal barrier.The measured rotational constants agree very well with calculations based on the C 6 coefficient. The discovery of a splitting of the rotational components into subcomponents indicates an uncommon angular momentum coupling described by Hund's case. Variations in the depth of the subcomponents indicates a similar splitting in the ground state, with the energies of the substates based on the alignment of the rubidium atom's magnetic dipole moment relative to the angular momentum carried by an approaching ytterbium atom. This creates an additional ground state barrier, partially suppressing some of the subcomponents. Using a rate equation model developed for this purpose, a maximum formation rate of 2.5.10 6 molecules per second was calculated over the volume of the entire trap. The work presented here is an important step on

  2. ˝FLUMINENSIA˝ VON FRAN KURELAC

    Directory of Open Access Journals (Sweden)

    Leopoldina Veronika Banaš

    1990-01-01

    Full Text Available Das Buch "Fluminensia" (1862 von Fran Kurelac enthält die für die Schulfestlichkeiten geschriebenen Reden, Gelegenheitsgedichte - Ehrengedichte den bedeutenden und verdienstvollen Zeitgenossen gewidmet: dem Bischof von Senj und Modrus" Mirko Ožegović, Bartol Zmajic von Bakar, dem kroatischen Ban Josip Jelačić u.a. Danach folgen Aufrufe ("Proglasi" aus stürmischem 1848, gerichtet auf die Granzlandbewohner, Deutscher, ungarische Kroaten, Rumänen und Slawonier. Die Aufrufe wurden von Kurelac im Namen der Banalregierung beschrieben. Am Ende des Buches steht eine sprachwissenschaftliche Abhandlung über die ubstantivbiegung. Die für die Schulfestlichkeiten geschreibenen Reden sind wissenschaftliche Inhalte, essaystisch-didaktisch gestalltet, mit der Meldung über die Bedeutung der Wisenschaft, über die Bedeutung und Rolle der Sprache und des Buches für den Fortschritt des Volkes. Der Verfasser widmete dieses Buch seinen ehemaligen Schülern. "Fluminensia" nimmt eine wichtige Stelle in literarischer und sprachwissenschaftlicher Schöpfung auf dem Gebiet von Rijeka und Kroatien im 19. Jahrhundert ein.

  3. Privatiserung von Geschichte. Probleme einer differenzierten Aufarbeitung

    Directory of Open Access Journals (Sweden)

    Birthe Kundrus

    2000-11-01

    Full Text Available Ausgangspunkt der Untersuchung von Vera Neumann ist die These, daß im Krieg Erlebtes und Erlittenes in den Wiederaufbau- und Wirtschaftswunderjahren Westdeutschlands einem Thematisierungstabu unterlegen sei. Anhand von 50 Interviews, die in den 80er Jahren im Rahmen des von Lutz Niethammer geleiteten Projekts „Lebensgeschichte und Sozialgeschichte im Ruhrgebiet 1930–1960“ (LUSIR entstanden sind und die sie jetzt anhand der Tonbandprotokolle und Abschriften ein zweites Mal auswertet, möchte die Historikerin diese Verschüttungen aufspüren. Im Anschluß an Niethammers These der „Privatisierung von Geschichte“ will sie zeigen, daß seelische und körperliche Kriegsfolgen wie Deprivations- und Überlastungsgefühle, der Verlust von Angehörigen und Kriegsbeschädigungen „privatisiert“, d.h. an die Familien übertragen wurden. Dort seien dann in erster Linie die weiblichen Familienmitglieder mit der Versorgungs- und Pflegearbeit konfrontiert worden. An vier Fallbeispiele schließt sich eine detaillierte Auswertung des gesamten Interviewmaterials an. Diesen Teilen folgt ein Abschnitt zur staatlichen Kriegsopferversorgung in der frühen Bundesrepublik.

  4. A new von Mises probabilistic formula for quartet invariants

    International Nuclear Information System (INIS)

    Giacovazzo, C.; Camalli, M.; Spagna, R.

    1989-01-01

    Von Mises formulas for quartet invariants, even is useful in most cases of practical interest, suffer from some systematic errors. A new von Mises formula is suggested with better theoretical features. (orig.)

  5. Kerttu Wagner. Die historischen romane von Jaan Kross / Wolfgang Drechsler

    Index Scriptorium Estoniae

    Drechsler, Wolfgang, 1963-

    2001-01-01

    Arvustus: Wagner, Kerttu. Die historischen Romane von Jaan Kross : am Beispiel einer Untersuchung der deutschen und englischen Übersetzungen von "Professor Martensi ärasõit" (1984). Frankfurt am Main [etc.] : P. Lang, 2001.

  6. IAS 25, Bilanzierung von Finanzinvestitionen (Accounting for Investments)

    OpenAIRE

    Steiner, Manfred

    1997-01-01

    IAS 25, Bilanzierung von Finanzinvestitionen (Accounting for Investments). - In: Rechnungslegung nach International Accounting Standards (IAS) / hrsg. von Jörg Baetge ... - Stuttgart : Schäffer-Poeschel, 1997. - S. 923-953

  7. Borel reductibility and classification of von neumann algebras

    DEFF Research Database (Denmark)

    Sasyk, R.; Törnquist, Asger Dag

    2009-01-01

    We announce some new results regarding the classification problem for separable von Neumann algebras. Our results are obtained by applying the notion of Borel reducibility and Hjorth's theory of turbulence to the isomorphism relation for separable von Neumann algebras....

  8. Design, synthesis and luminescence properties of Ba2 YB2 O6 Cl- and Ba2 YB2 O6 F-based phosphors.

    Science.gov (United States)

    Chen, Wanping; Yang, Xin; Liu, Yan; Dai, Xiaoyan

    2015-05-01

    Using a high-temperature solid-state reaction, the chlorine in Ba2 YB2 O6 Cl is gradually replaced by F, and a new compound with the nominal chemical formula Ba2 YB2 O6 F and two phosphors doped with Ce(3+) and Eu(3+) , respectively, are obtained. X-Ray diffraction and photoluminescence spectroscopy are used to characterize the as-synthesized samples. The as-synthesized Ba2 YB2 O6 Cl exhibits bright blue emission in the spectral range ~ 330-410 nm with a maximum around 363 nm under X-ray or UV excitation. Ba2 YB2 O6 F:0.01Ce(3+) exhibits blue emission in the range ~ 340-570 nm with a maximum around 383 nm. Ba2 YB2 O6 F:0.01Eu(3+) exhibits a predominantly (5) D0 -(7)  F2 emission (~610 nm) and the relative intensities of the (5) D0 -(7)  F0,1,2 emissions are tunable under different wavelength UV excitation. The luminescence behaviors of the two phosphors are explained simply in terms of the host composition and site occupancy probability of Ce(3+) and Eu(3+) , respectively. The results indicate that these phosphors have potential application as a blue phosphor or as a red phosphor. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Medien und Berufsvorstellungen von Kindern: eine experimentelle Studie zum Einfluss von Kinderbüchern auf das Berufsspektrum von Kindergartenkindern

    OpenAIRE

    Brüggemann, Tim; Gehrau, Volker; Handrup, Jutta

    2015-01-01

    "Der Beitrag thematisiert zunächst den Stand der beruflichen Orientierung von Jugendlichen sowie die pädagogischen Bemühungen beim Übergang Schule-Beruf, insbesondere im Hinblick auf eine Erweiterung des häufig engen Spektrums von Berufen, die bei der Berufswahl berücksichtig werden. Dabei richten sich die Bestrebungen, diesem Problem entgegenzuwirken, bislang vor allem auf Jugendliche. Anschließend wird anhand vorliegender Ergebnisse aus der Medienforschung diskutiert, in welcher Weise Masse...

  10. Doença de von Willebrand e anestesia Enfermedad de von Willebrand y anestesia Von Willebrand's disease and anesthesia

    Directory of Open Access Journals (Sweden)

    Fabiano Timbó Barbosa

    2007-06-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A doença de von Willebrand ocorre devido à mutação no cromossomo 12 e é caracterizada por deficiência qualitativa ou quantitativa do fator de von Willebrand. A diversidade de mutações leva ao aparecimento das mais variadas manifestações clínicas possibilitando a divisão dos pacientes em vários tipos e subtipos clínicos. A coagulopatia se manifesta basicamente através da disfunção plaquetária associada à diminuição dos níveis séricos do fator VIII coagulante. O objetivo dessa revisão foi mostrar os cuidados relacionados aos pacientes portadores da doença de von Willebrand durante o período perioperatório. CONTEÚDO: Foram definidas as características da doença de von Willebrand quanto à fisiopatologia, à classificação, ao diagnóstico laboratorial, ao tratamento atual e aos cuidados com o manuseio do paciente no período perioperatório. CONCLUSÕES: A doença de von Willebrand é o distúrbio hemorrágico hereditário mais comum, porém ela é subdiagnosticada pela complexidade da própria doença. A correta classificação do paciente, o uso apropriado da desmopressina e a transfusão do fator de von Willebrand são medidas fundamentais para a realização do procedimento anestésico bem-sucedido.JUSTIFICATIVA Y OBJETIVOS: La enfermedad de von Willebrand ocurre debido a la mutación en el cromosoma 12 y se caracteriza por la deficiencia cualitativa o cuantitativa del factor de von Willebrand. La diversidad de mutaciones conlleva al aparecimiento de las más variadas manifestaciones clínicas posibilitando la división de los pacientes en varios tipos y subtipos clínicos. La coagulopatía se manifiesta básicamente a través de la disfunción plaquetaria asociada con la disminución de los niveles séricos del factor VIII coagulante. El objetivo de esa revisión fue mostrar los cuidados relacionados con las pacientes portadoras de la enfermedad de von Willebrand durante el per

  11. Gemeinsam hilfreich oder einsam lästig? Beurteilung von praktikumsbegleitenden Weblogs von angehenden Lehrpersonen

    Directory of Open Access Journals (Sweden)

    Nives Egger

    2017-02-01

    Full Text Available Weblogs werden an Hochschulen vermehrt zur Unterstützung von Lern- und Reflexionsprozessen eingesetzt, in der Lehrer/innenbildung auch zunehmend während der berufspraktischen Ausbildung. Die Studierenden beurteilen den Einsatz von Weblogs jedoch unterschiedlich. Dabei ist wenig bekannt, welchen Einfluss die Vergabe und das Erhalten von Peerfeedback auf den Beurteilungsprozess von praktikumsbegleitenden Weblogs sowie auf den Umfang von Blogpostings haben. Im folgenden Beitrag wird dieser Frage mittels einer Befragung von 74 angehenden Lehrpersonen nachgegangen, die praktikumsbegleitende Weblogs mit oder ohne Peerfeedback nutzten, um über herausfordernde Ereignisse im Praktikum zu reflektieren. Die Ergebnisse zeigen, dass Studierende, die Peerfeedback erhielten und andere Blogbeiträge kommentierten, den Weblogeinsatz nützlicher einschätzen sowie eine höhere Motivation und positivere Einstellung gegenüber den Einsatz von Weblogs aufweisen als Studierende, die ohne Peerfeedback bloggen. Keinen Einfluss hat Peerfeedback auf den Umfang der Blogbeiträge und auf die dafür aufgewendete Zeit.

  12. Von Willebrand protein binds to extracellular matrices independently of collagen.

    OpenAIRE

    Wagner, D D; Urban-Pickering, M; Marder, V J

    1984-01-01

    Von Willebrand protein is present in the extracellular matrix of endothelial cells where it codistributes with fibronectin and types IV and V collagen. Bacterial collagenase digestion of endothelial cells removed fibrillar collagen, but the pattern of fibronectin and of von Willebrand protein remained undisturbed. Exogenous von Willebrand protein bound to matrices of different cells, whether rich or poor in collagen. von Willebrand protein also decorated the matrix of cells grown in the prese...

  13. Transition probabilities up to I = 36+ in 160Yb

    International Nuclear Information System (INIS)

    Johnson, N.R.; McGowan, F.K.; Winchell, D.F.; Baktash, C.; Garrett, J.D.; Lee, I.Y.; Wells, J.C.; Chaturvedi, L.; Gao, W.B.; Ma, W.C.; Pilotte, S.; Yu, C.H.

    1992-01-01

    During the past dozen years or so, numerous groups have worked on the properties of the ytterbium nuclei and we at Oak Ridge have been actively involved in the study of many of these nuclei. We have concentrated on lifetime measurements of their high-spin states because it is from the lifetime of a state that one can determine Q t , the transition quadrupole moment. The importance of obtaining a Q t value is in that it reflects the intrinsic part of the wave function and, hence, provides an indicator of the collectivity. This paper presents the results from recent Doppler broadened line shape measurements in 16O Yb at very large rotational frequencies of bar Hω∼0.36 - 0.50 MeV (I = 22 + -36 + )

  14. High pressure transport properties of Yb2Cu9

    International Nuclear Information System (INIS)

    Spendeler, L.; Jaccard, D.; Sierro, J.; Flouquet, J.

    1992-01-01

    The electrical resistivity (ρ) and the absolute thermopower (S) of high-purity Yb 2 Cu 9 have been measured between 1.2 and 300 K at pressures up to 17 kbar and in magnetic fields up to 6 T. At zero pressure the three measured samples show a Kondo peak in the resistivity at 17 K. Furthermore for one of them the resistivity rises below 5 K. Under pressure, the Kondo peak in ρ slowly moves towards lower temperatures indicating a decrease of the Kondo temperature T K , in good agreement with specific heat results. The increase of ρ below 5 K disappears completely for pressure lower than 1 kbar and the residual resistivity remains high. The thermopower S exhibits similar trends. Magnetic field dependences of both ρ and S are weak. No evidence of magnetic ordering has been detected up to 17.6 kbar

  15. High-average-power diode-pumped Yb: YAG lasers

    International Nuclear Information System (INIS)

    Avizonis, P V; Beach, R; Bibeau, C M; Emanuel, M A; Harris, D G; Honea, E C; Monroe, R S; Payne, S A; Skidmore, J A; Sutton, S B

    1999-01-01

    A scaleable diode end-pumping technology for high-average-power slab and rod lasers has been under development for the past several years at Lawrence Livermore National Laboratory (LLNL). This technology has particular application to high average power Yb:YAG lasers that utilize a rod configured gain element. Previously, this rod configured approach has achieved average output powers in a single 5 cm long by 2 mm diameter Yb:YAG rod of 430 W cw and 280 W q-switched. High beam quality (M(sup 2)= 2.4) q-switched operation has also been demonstrated at over 180 W of average output power. More recently, using a dual rod configuration consisting of two, 5 cm long by 2 mm diameter laser rods with birefringence compensation, we have achieved 1080 W of cw output with an M(sup 2) value of 13.5 at an optical-to-optical conversion efficiency of 27.5%. With the same dual rod laser operated in a q-switched mode, we have also demonstrated 532 W of average power with an M(sup 2) and lt; 2.5 at 17% optical-to-optical conversion efficiency. These q-switched results were obtained at a 10 kHz repetition rate and resulted in 77 nsec pulse durations. These improved levels of operational performance have been achieved as a result of technology advancements made in several areas that will be covered in this manuscript. These enhancements to our architecture include: (1) Hollow lens ducts that enable the use of advanced cavity architectures permitting birefringence compensation and the ability to run in large aperture-filling near-diffraction-limited modes. (2) Compound laser rods with flanged-nonabsorbing-endcaps fabricated by diffusion bonding. (3) Techniques for suppressing amplified spontaneous emission (ASE) and parasitics in the polished barrel rods

  16. Synthesis and characterization of Nd3+: Yb3+ co-doped near infrared sensitive fluorapatite nanoparticles as a bioimaging probe

    Science.gov (United States)

    Karthi, S.; Kumar, G. A.; Sardar, D. K.; Santhosh, C.; Girija, E. K.

    2018-03-01

    Trivalent Nd and Yb co-doped rod shaped hexagonal phase fluorapatite (FAP) nanoparticles of length and width about 32 and 13 nm, respectively were prepared by hydrothermal method and investigated the ability for 980 nm emission via Nd3+ → Yb3+ energy transfer with the objective of utilizing them in biomedical imaging. Nd3+ → Yb3+ energy transfer in FAP was studied as a function of both Nd3+ and Yb3+ concentrations and found that when Yb3+ concentration was 10 mol% the FAP phase has partially turned in to YbPO4 phase. The Yb3+ emission intensity at 980 nm significantly increased up to 5 mol% Yb3+ doping and then reduced drastically for further increase in its concentration. Nd3+ →Yb3+ energy transfer rates were evaluated from the decay curves and found that a transfer rate of 71% for 2 mol% Nd3+ co-doped with 5 mol% Yb3+. The cytocompatibility test with fibroblast like cells using MTT assay revealed that the nanoparticles are compatible with the cells.

  17. YB-1 expression promotes epithelial-to-mesenchymal transition in prostate cancer that is inhibited by a small molecule fisetin

    Science.gov (United States)

    Khan, Mohammad Imran; Adhami, Vaqar Mustafa; Lall, Rahul Kumar; Sechi, Mario; Joshi, Dinesh C.; Haidar, Omar M.; Syed, Deeba Nadeem; Siddiqui, Imtiaz Ahmad; Chiu, Shing-Yan; Mukhtar, Hasan

    2014-01-01

    Epithelial-to-mesenchymal transition (EMT) plays an important role in prostate cancer (PCa) metastasis. The transcription/translation regulatory Y-box binding protein-1 (YB-1) is known to be associated with cancer metastasis. We observed that YB-1 expression increased with tumor grade and showed an inverse relationship with E-cadherin in a human PCa tissue array. Forced YB-1 expression induced a mesenchymal morphology that was associated with down regulation of epithelial markers. Silencing of YB-1 reversed mesenchymal features and decreased cell proliferation, migration and invasion in PCa cells. YB-1 is activated directly via Akt mediated phosphorylation at Ser102 within the cold shock domain (CSD). We next identified fisetin as an inhibitor of YB-1 activation. Computational docking and molecular dynamics suggested that fisetin binds on the residues from β1 - β4 strands of CSD, hindering Akt's interaction with YB-1. Calculated free binding energy ranged from −11.9845 to −9.6273 kcal/mol. Plasmon Surface Resonance studies showed that fisetin binds to YB-1 with an affinity of approximately 35 μM, with both slow association and dissociation. Fisetin also inhibited EGF induced YB-1 phosphorylation and markers of EMT both in vitro and in vivo. Collectively our data suggest that YB-1 induces EMT in PCa and identify fisetin as an inhibitor of its activation. PMID:24770864

  18. [Anja Wilhelmi. Lebensweltlen von Frauen der deutschen Oberschicht im Baltikum (1800-1939). Eine Untersuchung anhand von Autobiographien] / Alexander Ewig

    Index Scriptorium Estoniae

    Ewig, Alexander, 1980-

    2011-01-01

    Arvustus: Wilhelmi, Anja. Lebenswelten von Frauen der deutschen Oberschicht im Baltikum (1800-1939). Eine Untersuchung anhand von Autobiographien. (Veröffentlichungen des Nordost-Instituts, 10.) (Wiesbaden : HArrassowitz 2008)

  19. Gasification of liquid manure; Vergasung von Guelle

    Energy Technology Data Exchange (ETDEWEB)

    Gudenau, H.W.; Hoberg, H.; Hirsch, U. [Technische Hochschule Aachen (Germany). Inst. fuer Eisenhuettenkunde

    1996-12-31

    The potential of thermal use of liquid manure is investigated. It is recommended to separate the liquid and solid fraction. While the liquid fraction can be used as fertilizer, the solid fraction can be used for generating a fuel gas for combined heat and power generation. (orig) [Deutsch] Die Untersuchungen haben ergeben, dass in der thermischen Verwertung von Guelle ein bisher nur wenig genutztes Potential vorliegt. Die zum Anbau von Getreide notwendige Duengung kann durch Separation von Guelle in Fest- und Duennfraktion effektiver und kostenguenstiger durchgefuehrt werden. Der Naehrstoffgehalt des Guellefeststoffs sollte durch thermische Aufbereitung aufkonzentriert werden, so dass eine Vermarktung auch mit laengeren Transpoertwegen darstellbar ist. Die bei der thermischen Behandlung gewonnene Waerme kann prozessintern genutzt und ueberschuessige Waerme an Abnehmer in der naeheren Umgebung geliefert werden. Genauso besteht die Moeglichkeit, ein Brenngas zu erzeugen und die Energie mit Kraft-Waerme-Kopplung zu nutzen. (orig)

  20. Gasification of liquid manure; Vergasung von Guelle

    Energy Technology Data Exchange (ETDEWEB)

    Gudenau, H W; Hoberg, H; Hirsch, U [Technische Hochschule Aachen (Germany). Inst. fuer Eisenhuettenkunde

    1997-12-31

    The potential of thermal use of liquid manure is investigated. It is recommended to separate the liquid and solid fraction. While the liquid fraction can be used as fertilizer, the solid fraction can be used for generating a fuel gas for combined heat and power generation. (orig) [Deutsch] Die Untersuchungen haben ergeben, dass in der thermischen Verwertung von Guelle ein bisher nur wenig genutztes Potential vorliegt. Die zum Anbau von Getreide notwendige Duengung kann durch Separation von Guelle in Fest- und Duennfraktion effektiver und kostenguenstiger durchgefuehrt werden. Der Naehrstoffgehalt des Guellefeststoffs sollte durch thermische Aufbereitung aufkonzentriert werden, so dass eine Vermarktung auch mit laengeren Transpoertwegen darstellbar ist. Die bei der thermischen Behandlung gewonnene Waerme kann prozessintern genutzt und ueberschuessige Waerme an Abnehmer in der naeheren Umgebung geliefert werden. Genauso besteht die Moeglichkeit, ein Brenngas zu erzeugen und die Energie mit Kraft-Waerme-Kopplung zu nutzen. (orig)

  1. Spectral theory and quotients in Von Neumann algebras | West ...

    African Journals Online (AJOL)

    In this note we consider to what extent the functional calculus and the spectral theory in von Neumann algebras are preserved by the taking of quotients relative to two-sided ideals of the von Neumann algebra. Keywords:von Neumann algebra, functional calculus, spectral theory, quotient algebras. Quaestiones ...

  2. Microwave hydrothermal synthesis and upconversion properties of Yb3+/Er3+ doped YVO4 nanoparticles.

    Science.gov (United States)

    Kshetri, Yuwaraj K; Regmi, Chhabilal; Kim, Hak-Soo; Lee, Soo Wohn; Kim, Tae-Ho

    2018-05-18

    Yb 3+ and Er 3+ doped YVO 4 (Yb 3+ /Er 3+ :YVO 4 ) nanoparticles with highly efficient near-infrared to visible upconversion properties have been synthesized by microwave hydrothermal process. Uniform-sized Yb 3+ /Er 3+ :YVO 4 nanoparticles were synthesized within 1 h at 140 °C which is relatively faster than the conventional hydrothermal process. Under 980 nm laser excitation, strong green and less strong red emissions are observed which are attributed to 2 H 11/2 , 4 S 3/2 to 4 I 15/2 and 4 F 9/2 to 4 I 15/2 transitions of Er 3+ respectively. The emission intensity is found to depend strongly on the concentration of Yb 3+ . The quadratic dependence of upconversion intensity on the excitation power indicates that the upconversion process is governed by two-photon absorption process.

  3. Instability of Yb3+ and Pr3+ low-symmetry luminescence centers in gallium phosphide

    International Nuclear Information System (INIS)

    Kasatkin, V.A.

    1985-01-01

    The stability of γb 3+ and Pr 3+ low-symmetry luminescence centers formed in gallium phosphide during quenching were studied in the process of durable storage and annealing. Observation of the Yb 3+ and Pr 3+ centrer states was accomplished by the photoluminescence spectra at 18 K. It has been established that annealing in the dark under normal conditions results in a reduced integral luminescence intensity of all low-symmetry Yb 3+ and Pr 3+ centers. Annealing of quenched GaP and GaP saples at 400 K results in complete disappearance of intracenter luminescence of Pr 3+ and low-symmetry Yb 3+ centers. Decomposition during storage and low anealing temperature point to the instability of low-symmetry centers of Pr 3+ and Yb 3+ luminescence

  4. A mass spectrometric study of the neutral and ionic vapor components of ytterbium chlorides; formation enthalpies of YbCl2 and YbCl3 molecules, and YbCl3- and YbCl4- ions in the gas phase

    International Nuclear Information System (INIS)

    Kuznetsov, F.Yh.; Kudin, L.S.; Pogrebnoj, A.M.; Butman, M.F.; Burdukovskaya, G.G.

    1997-01-01

    Ionic and neutral components of saturated vapour over the ytterbium di-and trichloride is studied through the Knudsen effusive method with mass-spectromic registration of evaporated products within the temperature range of 1000-1300 K. It is found that ytterbium trichloride is subjected to thermal decomposition with formation of ytterbium dichloride and molecular chloride. Sublimation enthalpy and enthalpy of YbCl 2 and YbCl 3 molecules formation in a gaseous phase at 298 K, comprising 356±6, 293±8, -425±6 and -667±6 kJ/mole correspondingly, are determined with application of 2 and 3 thermodynamical laws. Enthalpies of YbCl 3 - and YbCl 4 - negative ions formation in a gaseous phase at 298 K equal to -895 and -1211±30 kJ/mole correspondingly are calculated by measured equilibrium constants ion-molecular reaction. 30 refs., 3 figs., 3 tabs

  5. On the valence state of Yb and Ce in transition metal intermetallic compounds

    International Nuclear Information System (INIS)

    Boer, F.R. de; Dijkman, W.H.; Mattens, W.C.M.

    1979-01-01

    In the pure state Yb is a divalent metal, similar to Ca; in alloys it can become trivalent like the majority of the rare earth metals. Using a value of 38 kJ (mol Yb) -1 for the energy difference between divalent and trivalent Yb metal and using model calculations for the heat of formation of intermetallic compounds, the authors are able to account for the existing information on the valence state of Yb in transition metal compounds. A similar analysis of compounds of Ce with transition metals shows that a model in which the 4f electron is treated as a core electron, i.e. being absent in the tetravalent modification of Ce and present as a fully localized electron in trivalent Ce, does not apply. (Auth.)

  6. Laser induced broad band anti-Stokes white emission from LiYbF4 nanocrystals

    Institute of Scientific and Technical Information of China (English)

    L. Marciniak; R. Tomala; M. Stefanski; D. Hreniak; W. Strek

    2016-01-01

    Spectroscopic properties of tetragonal LiYbF4 nanocrystals under high dense NIR excitation at vacuum condition were in-vestigated. White, broad band emission covering whole visible part of the spectrum from LiYbF4 nanocrystals was observed. Its in-tensity strongly depended on the excitation power, excitation wavelength and ambient pressure. Temperature of the nanocrystals un-der 975 nm excitation was determined as a function of excitation power. Strong photo-induced current was observed from LiYbF4 pallet. The emission kinetic was analyzed. The mechanism of the anti-Stokes white emission was discussed in terms of the la-ser-induced charge transfer emission from Yb2+ states.

  7. Microwave hydrothermal synthesis and upconversion properties of Yb3+/Er3+ doped YVO4 nanoparticles

    Science.gov (United States)

    Kshetri, Yuwaraj K.; Regmi, Chhabilal; Kim, Hak-Soo; Wohn Lee, Soo; Kim, Tae-Ho

    2018-05-01

    Yb3+ and Er3+ doped YVO4 (Yb3+/Er3+:YVO4) nanoparticles with highly efficient near-infrared to visible upconversion properties have been synthesized by microwave hydrothermal process. Uniform-sized Yb3+/Er3+:YVO4 nanoparticles were synthesized within 1 h at 140 °C which is relatively faster than the conventional hydrothermal process. Under 980 nm laser excitation, strong green and less strong red emissions are observed which are attributed to 2H11/2, 4S3/2 to 4I15/2 and 4F9/2 to 4I15/2 transitions of Er3+ respectively. The emission intensity is found to depend strongly on the concentration of Yb3+. The quadratic dependence of upconversion intensity on the excitation power indicates that the upconversion process is governed by two-photon absorption process.

  8. High energy single frequency Yb:YAG crystalline fiber waveguide master oscillator power amplifier, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective is to demonstrate the concept of Yb:YAG crystalline fiber MOPA laser and investigation the technical feasibility toward 50 mJ single frequency...

  9. Der Einfluss von sozialer Ungleichheit und kulturellen Unterschieden auf die Wahrnehmung von finanziellen und Arbeitsplatzrisiken: Überlegungen zur Risikogesellschaft

    OpenAIRE

    Abbott, David; Quilgars, Deborah; Jones, Anwen

    2006-01-01

    Der vorliegende Artikel beruht auf Daten einer Studie, die sich mit der Frage beschäftigt, wie verschiedene soziale und kulturelle Gruppen die Risiken von Einkommens- und Arbeitsplatzverlust wahrnehmen und darauf reagieren. Autoren wie LASH, DOUGLAS und LUPTON betonten die Bedeutung von Gruppenzugehörigkeit und sozialen Kategorien für die Strukturierung der Reaktionsweisen auf verschiedene Risikoarten. Sie sprechen daher lieber von Risikokulturen als von der Risikogesellschaft. Trotzdem erken...

  10. Characterization and Computation of Yb/TiO2 and Its Photocatalytic Degradation with Benzohydroxamic Acid

    Directory of Open Access Journals (Sweden)

    Xianping Luo

    2017-11-01

    Full Text Available Yb-doped TiO2 (Yb/TiO2 compositions were synthesized by sol-gel method, and the prepared materials were characterized by X-ray Diffraction (XRD, X-ray photoelectron spectroscopy (XPS, UV-visible diffuse-reflectance spectrum (UV-Vis DRS, transmission electron microscope (TEM and high resolution transmission electron microscope (HRTEM, energy dispersive spectrometer (EDS, and N2 adsorption. A beneficiation reagent of benzohydroxamic acid (BHA was used to test the photocatalytic activity of Yb/TiO2. The characterizations indicate that the doping of Yb could inhibit the crystal growth of TiO2, enhance the specific surface area, increase the binding energy of Ti2p, and also slightly expand the adsorption ranges to visible light. Furthermore, the computation of band structure also indicates that Yb-doped TiO2 could make the forbidden band narrower than pure anatase TiO2, which presents a red shift in the absorption spectrum. As a result of the photodegradation experiment on BHA, Yb/TiO2 (0.50% in mass sintered at 450 °C displayed the highest catalytic activity for BHA when compared with pure TiO2 or other doped Yb/TiO2 compositions, and more than 89.2% of the total organic carbon was removed after 120 min. Almost all anions, including Cl−, HCO3−, NO3−, and SO42−, inhibited the degradation of BHA by Yb/TiO2, and their inhibition effects followed the order of HCO3− > NO3− > SO42− > Cl−. Cations of Na+, K+, Ca2+, and Mg2+ displayed a slight suppressing effect due to the impact of Cl− coexisting in the solution. In addition, Yb/TiO2 maintained a high photocatalytic ability with respect to BHA after four runs. It is hypothesized that ·OH is one of the main species involved in the photodegradation of BHA, and the mutual transformation of Yb3+ and Yb2+ could promote the separation of electron-hole pairs.

  11. Bewertung von Fahrzeuggeräuschen

    Science.gov (United States)

    Genuit, Klaus; Schulte-Fortkamp, Brigitte; Fiebig, André; Haverkamp, Michael

    Bei der Wahrnehmung und Beurteilung eines Automobils sind unzählige Merkmale und Eigenschaften von Bedeutung. Dabei können Merkmale objektiv-technisch beschrieben werden, wie Angaben zur Motorisierung, Höchstgeschwindigkeit, Drehmoment, zulässige Zuladung, Verbrauch usw. Daneben sind weitere Eigenschaften von Bedeutung, die sich einer einfachen objektiv-technischen Beschreibung entziehen. Hier sind Begriffe zu nennen, wie Sicherheit, allgemeine Qualitätsanmutung, Design, Ergonomie, Komfort, Haptik, Fahrdynamik, Zuverlässigkeit, die deutlich schwieriger objektiv erfassbar und beschreibbar sind (Abb. 4.1).

  12. Asymptotic analysis of a von Koch beam

    International Nuclear Information System (INIS)

    Carpinteri, Alberto; Pugno, Nicola; Sapora, Alberto

    2009-01-01

    Fractal geometry is used in diverse research areas, being an useful tool in describing the mechanical behaviour of natural and man-made structures. In this paper, the structural behaviour of a von Koch cantilever beam is analyzed in the small deformations regime. Analytical recursive formulae for the strain energy scaling are derived, which have been found in good agreement with numerical simulations. Energy considerations suggest a peculiar scaling for the beam rigidity in order to prevent compliance divergence. The results are then extended to evaluate the stiffness matrix of a von Koch beam.

  13. Von Mumien, Cyborgs und Röntgenbildern

    Directory of Open Access Journals (Sweden)

    Regina Schleicher

    2004-03-01

    Full Text Available Unter dem Titel Techniken der Reproduktion liegt ein Sammelband vor, der die Beiträge einer Tagung an der Universität Paderborn vom Dezember 2001 enthält. In enger Verknüpfung verschiedener disziplinärer Perspektiven werden Schlaglichter auf eine Vielzahl von Themen geworfen, die sich mit dem Begriff „Reproduktion“ verbinden. Dabei wird deutlich, wie eng die Geschichte der Medien und die Entwicklung von Technologien der biologischen Fortpflanzung miteinander verzahnt sind.

  14. The complexity of the CaF2:Yb system: evidence that CaF2:Yb2+ is not an impurity trapped exciton system

    Science.gov (United States)

    Mackeen, Cameron; Bridges, Frank; Kozina, Michael; Mehta, Apurva; Reid, M. F.; Wells, J.-P. R.; BarandiaráN, Zoila

    Fluorite crystal structures doped with rare-earth elements exhibit an anomalous redshifted luminescence upon UV excitation, generally attributed to the relaxation of impurity trapped excitons (ITE). We find that the intensity of this luminescence decreases as the total concentration of Yb 2+ increases in unexposed samples, which is in conflict with the currently accepted ITE model. Further, using x-ray absorption spectroscopy and UV-vis studies of CaF2:Yb, we find a large (but reversible) Yb valence reduction upon x-ray exposure at 200 K - from mostly 3+ to 2+. This valence reduction is stable for long time periods at low T ITE model; the data appear more consistent with an intervalence charge transfer (IVCT) model. It is likely that many similar ITE systems have also been misidentified.

  15. Optical and magnetic properties of Yb ion-doped cobalt-based ZnO ...

    Indian Academy of Sciences (India)

    Administrator

    The X-ray photoelectron spectral peaks for Yb 4f ions ... temperature with high coercivity due to the contribution of both 3d and 4f exchange interaction with the host ... Mn,4,5 Co,6–9 Ni2,10 Fe11–13 and Cu,2,14 and reported to .... water separately under stirring. .... different concentrations of Yb added ZnO : Co, nanopar-.

  16. Electron spin resonance in Yb-based Kondo-lattice systems

    International Nuclear Information System (INIS)

    Wykhoff, Jan

    2010-01-01

    The systems Yb 1-w A 1-w (Rh 1-x Co x )(Si 1-y Ge y ) 2 with A=La respectively Lu, as well as YbIr 2 Si 2 are studied. The measurements are presented sortedly for systems, dopings, and external parameters. Beside these external parameters furthermore the orientation of the sample related to the quasistatic magnetic field and the microwave magnetic field was varied.

  17. Yb-doped rod-type photonic crystal fibers for single-mode amplification

    DEFF Research Database (Denmark)

    Poli, Frederica; Passaro, Davide; Cucinotta, Annamaria

    2009-01-01

    The competition among the guided modes in rod-type photonic crystal fibers with a low refractive index ring in the Yb-doped core is investigated with an amplifier model to demonstrate the effective higher-order mode suppression.......The competition among the guided modes in rod-type photonic crystal fibers with a low refractive index ring in the Yb-doped core is investigated with an amplifier model to demonstrate the effective higher-order mode suppression....

  18. Guided mode gain competition in Yb-doped rod-type photonic crystal fibers

    DEFF Research Database (Denmark)

    Poli, Federica; Passaro, Davide; Cucinotta, Annamaria

    2009-01-01

    The gain competition among the guided modes in Yb-doped rod-type photonic crystal fibers with a low refractive index core is investigated with a spatial model to demonstrate the fiber effective single-mode behaviour.......The gain competition among the guided modes in Yb-doped rod-type photonic crystal fibers with a low refractive index core is investigated with a spatial model to demonstrate the fiber effective single-mode behaviour....

  19. Treatment of Neuroblastoma with an Engineered "Obligate" Anaerobic Salmonella typhimurium Strain YB1.

    Science.gov (United States)

    Ning, Bo-Tao; Yu, Bin; Chan, Shing; Chan, Jian-Liang; Huang, Jian-Dong; Chan, Godfrey Chi-Fung

    2017-01-01

    Purpose Neuroblastoma is an embryonic solid tumor derived from the progenitors of the sympathetic nervous system. More than half of the patients developed metastatic disease at the time of initial diagnosis and had poor outcome with current therapeutic approaches. In recent years, some obligate and facultative anaerobic bacteria were reported to target the hypoxic and necrotic region of solid tumor models and caused tumor regression. We recently successfully constructed an "obligate" anaerobic Salmonella strain YB1 that was applied in breast cancer nude mice model by us. Here, we report the application of YB1 in neuroblastoma treatment. Methods The anti-cancer effect and side-effects of YB1 was examined in both in vitro and in vivo experiment. Previous established orthotopic neuroblastoma SCID/beige murine model using SK-NLP/luciferase cell line was adopted. Results In vitro , YB1 induced apoptosis for up to 31.4% of the neuroblastoma cells under anaerobic condition, three times more than that under aerobic condition (10.9%). The expression of both Toll like Receptor 4 and 5 (TLR4 and TLR5) in cancer cells were significantly up-regulated ( p anaerobic condition. In mouse model, YB1 preferentially accumulated inside the core of the tumors, rather than in normal tissues as our previous reported. This is suggestive of the hypoxic nature of tumor core. Tumor growth was significantly retarded in YB1 treatment group ( n=6, P<0.01 ). Furthermore, there was no long-term organ damage noted in all the organs examined including heart, lung, liver, spleen and brain in the YB1 treated mice. Conclusion The genetic modified Salmonella strain YB1 is a promising anti-tumor strategy against the tumor bulk for neuroblastoma. Future study can be extended to other common cancer types to verify the relative efficacy on different neoplastic cells.

  20. Treatment of Neuroblastoma with an Engineered “Obligate” Anaerobic Salmonella typhimurium Strain YB1

    Science.gov (United States)

    Ning, Bo-Tao; Yu, Bin; Chan, Shing; Chan, Jian-liang; Huang, Jian-Dong; Chan, Godfrey Chi-Fung

    2017-01-01

    Purpose Neuroblastoma is an embryonic solid tumor derived from the progenitors of the sympathetic nervous system. More than half of the patients developed metastatic disease at the time of initial diagnosis and had poor outcome with current therapeutic approaches. In recent years, some obligate and facultative anaerobic bacteria were reported to target the hypoxic and necrotic region of solid tumor models and caused tumor regression. We recently successfully constructed an “obligate” anaerobic Salmonella strain YB1 that was applied in breast cancer nude mice model by us. Here, we report the application of YB1 in neuroblastoma treatment. Methods The anti-cancer effect and side-effects of YB1 was examined in both in vitro and in vivo experiment. Previous established orthotopic neuroblastoma SCID/beige murine model using SK-NLP/luciferase cell line was adopted. Results In vitro, YB1 induced apoptosis for up to 31.4% of the neuroblastoma cells under anaerobic condition, three times more than that under aerobic condition (10.9%). The expression of both Toll like Receptor 4 and 5 (TLR4 and TLR5) in cancer cells were significantly up-regulated (panaerobic condition. In mouse model, YB1 preferentially accumulated inside the core of the tumors, rather than in normal tissues as our previous reported. This is suggestive of the hypoxic nature of tumor core. Tumor growth was significantly retarded in YB1 treatment group (n=6, P<0.01). Furthermore, there was no long-term organ damage noted in all the organs examined including heart, lung, liver, spleen and brain in the YB1 treated mice. Conclusion The genetic modified Salmonella strain YB1 is a promising anti-tumor strategy against the tumor bulk for neuroblastoma. Future study can be extended to other common cancer types to verify the relative efficacy on different neoplastic cells. PMID:28775780

  1. BaYb2F8, a new radiation hard Cherenkov radiator for electromagnetic calorimeters

    International Nuclear Information System (INIS)

    Aseev, A.A.; Devitsin, E.G.; Komar, A.A.; Kozlov, V.A.; Hovsepyan, Yu.I.; Potashov, S.Yu.; Sokolovsky, K.A.; Uvarova, T.V.; Vasilchenko, V.G.

    1992-01-01

    Radiation hardness and optical properties of a new Cherenkov radiator, heavy fluoride BaYb 2 F 8 doped with various elements, have been studied. The above mentioned crystal has the density of 7 g/cm 3 , the radiation length is 1.28 cm and the Moliere radius 2.44 cm. High radiation hardness has been demonstrated for BaYb 2 F 8 doped with Tm, Pr, Tb. (orig.)

  2. β decays on the rotational levels of the 5/2+[642] 169Yb band

    International Nuclear Information System (INIS)

    Dzhelepov, B.S.; Zhukovskij, N.N.; Shestopalova, S.A.

    1993-01-01

    Competing 169 Lu β decays into rotational levels of 5/2 + [642] 169 Yb band are considered. Schemes of resolved β decay into 3 levels of deformed nucleus rotational bands, γ transitions linked with excitation and discharge of 169 Yb 5/2, 7/2, 9/2, 5/2 + [642] levels are presented. Matrix elements of axial-vector decay are determined. Data on 12 γ transitions in 169 Lu are presented

  3. Die Verteilung und Eigenschaften von Bodenformen in der Deutschen Bucht, eine Rekonstruktion der Karten von Ulrich (1973)

    DEFF Research Database (Denmark)

    Winter, Christian; Lefebvre, Alice; Benninghoff, Markus

    2015-01-01

    Entstehung, Gestalt und Dynamik von Bodenformen in vergleichsweise kleinen Untersuchungsgebieten ist die Arbeit von ULRICH (1973) über die Verteilung von Bodenformen in der Deutschen Bucht bis heute die einzige verfügbare zusammenhängende Darstellung für die deutsche Nordseeküste. Die analogen Karten und die...

  4. Expression of an enzymatically active Yb3 glutathione S-transferase in Escherichia coli and identification of its natural form in rat brain.

    Science.gov (United States)

    Abramovitz, M; Ishigaki, S; Felix, A M; Listowsky, I

    1988-11-25

    Glutathione S-transferases containing Yb3 subunits are relatively uncommon forms that are expressed in a tissue-specific manner and have not been identified unequivocally or characterized. A cDNA clone containing the entire coding sequence of Yb3 glutathione S-transferase mRNA was incorporated into a pIN-III expression vector used to transform Escherichia coli. A fusion Yb3-protein containing 14 additional amino acid residues at its N terminus was purified to homogeneity. Recombinant Yb3 was enzymatically active with both 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene as substrates but lacked glutathione peroxidase activity. Substrate specificity patterns of recombinant Yb3 were more limited than those of glutathione S-transferase isoenzymes containing Yb1- or Yb2-type subunits. Peptides corresponding to unique amino acid sequences of Yb3 as well as a peptide from a region of homology with Yb1 and Yb2 subunits were synthesized. These synthetic peptides were used to raise antibodies specific to Yb3 and others that cross-reacted with all Yb forms. Immunoblotting was utilized to identify the natural counterpart of recombinant Yb3 among rat glutathione transferases. Brain and testis glutathione S-transferases were rich in Yb3 subunits, but very little was found in liver or kidney. Physical properties, substrate specificities, and binding patterns of the recombinant protein paralleled properties of the natural isoenzyme isolated from brain.

  5. Characterization of the electronic properties of YB{sub 4} and YB{sub 6} using {sup 11}B NMR and first-principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, B.; Paluch, S.; Wolf, W.; Herzig, P.; Zogal, O.J.; Shitsevalova, N.; Paderno, Y

    2004-11-30

    Two compounds, tetragonal YB{sub 4} and cubic YB{sub 6}, have been investigated by electric-field gradient (EFG) and Knight shift measurements at the boron sites using the {sup 11}B nuclear magnetic resonance (NMR) technique and by performing first-principles calculations. In YB{sub 6} {sup 11}B (I=3/2) NMR spectra reveal patterns typical for an axially symmetric field gradient with a quadrupole coupling frequency of {nu}{sub Q}=600{+-}15 kHz. In the second boride (YB{sub 4}) three different EFGs were observed corresponding to the three inequivalent crystallographic sites for the boron atoms (4h, 4e, and 8j). They correspond to: {nu}{sub Q}(4h)=700{+-}30 kHz with an asymmetry parameter {eta}=0.02{+-}0.02, {nu}{sub Q}(4e)=515{+-}30 kHz, {eta}=0.00+0.02/-0.00, and {nu}{sub Q}(8j)=515{+-}40 kHz, {eta}=0.46{+-}0.08. The Knight shifts measured by magic-angle spinning (MAS) NMR at room temperature are very small being 0.6{+-}8 and -1{+-}8 ppm for YB{sub 4} and YB{sub 6}, respectively. For the theoretical calculations structure optimizations were performed as a first step. For the obtained structural parameters the EFGs were computed within the local-density approximation. Very satisfactory agreement between experimental and theoretical results is obtained both for the structural parameters and the B EFGs, thus confirming the underlying structural models. In addition to the EFGs, band structures, densities of states, and valence-electron densities are presented and the bonding situation in the two yttrium borides is discussed. The band-structure results are compatible with the very low values for the Knight shifts mentioned above.

  6. Emission properties of hydrothermal Yb3+, Er3+ and Yb3+, Tm3+-codoped Lu2O3 nanorods: upconversion, cathodoluminescence and assessment of waveguide behavior

    International Nuclear Information System (INIS)

    Barrera, Elixir William; Pujol, MarIa Cinta; DIaz, Francesc; Choi, Soo Bong; Rotermund, Fabian; Park, Kyung Ho; Jeong, Mun Seok; Cascales, Concepcion

    2011-01-01

    Yb 3+ and Ln 3+ (Ln 3+ = Er 3+ or Tm 3+ ) codoped Lu 2 O 3 nanorods with cubic Ia3-bar symmetry have been prepared by low temperature hydrothermal procedures, and their luminescence properties and waveguide behavior analyzed by means of scanning near-field optical microscopy (SNOM). Room temperature upconversion (UC) under excitation at 980 nm and cathodoluminescence (CL) spectra were studied as a function of the Yb + concentration in the prepared nanorods. UC spectra revealed the strong development of Er 3+4 F 9/2 → 4I 15/2 (red) and Tm 3+1 G 4 → 3 H 6 (blue) bands, which became the pre-eminent and even unique emissions for corresponding nanorods with the higher Yb 3+ concentration. Favored by the presence of large phonons in current nanorods, UC mechanisms that privilege the population of 4 F 9/2 and 1 G 4 emitting levels through phonon-assisted energy transfer and non-radiative relaxations account for these observed UC luminescence features. CL spectra show much more moderate development of the intensity ratio between the Er 3+4 F 9/2 → 4 I 15/2 (red) and 2 H 11/2 , 4 S 3/2 → 4 I 15/2 (green) emissions with the increase in the Yb 3+ content, while for Yb 3+ , Tm 3+ -codoped Lu 2 O 3 nanorods the dominant CL emission is Tm 3+1 D 2 → 3 F 4 (deep-blue). Uniform light emission along Yb 3+ , Er 3+ -codoped Lu 2 O 3 rods has been observed by using SNOM photoluminescence images; however, the rods seem to be too thin for propagation of light.

  7. Recent experiments at Brookhaven: level structure of N = 86 isotones 156Yb and 150Gd

    International Nuclear Information System (INIS)

    Sunyar, A.W.

    1980-01-01

    States of the N = 86 isotones 156 Yb and 150 Gd have been studied by means of the 144 Sm( 16 O,4n) 156 Yb, 113 In( 46 Ti,p2n) 156 Yb, and 124 Sn( 30 Si,4n) 150 Gd reactions. Levels have been established to spin 36 h-bar and over 12.5 MeV in excitation in 150 Gd and to beyond spin 25 h-bar in 156 Yb. The systematics of levels in the N = 86 isotones from 150 Gd to 156 Yb are described, and the near-spherical shell model description for states in this region to near spin 30 h-bar is discussed. A T/sub 1/2/ = 6 ns, 72-keV isomeric transition in 156 Yb has been discovered, and an E1 multipolarity is assigned to this transition. The spin-parity of the isomeric state is established as 11 - . 6 figures

  8. Infrared emission properties and energy transfer in ZnO-SiO2:Yb3+ composites

    International Nuclear Information System (INIS)

    Xiao, F.; Chen, R.; Shen, Y.Q.; Liu, B.; Gurzadyan, G.G.; Dong, Z.L.; Zhang, Q.Y.; Sun, H.D.

    2011-01-01

    Graphical abstract: Highlights: → ZnO-SiO 2 :Yb 3+ composites have been prepared via a facile sol-gel method. Intense near-infrared emission at around 1 μm has been obtained upon broadband ultraviolet light excitation. → Efficient energy transfer from ZnO quantum dots to Yb 3+ ions has been clarified by the systematic measurements and analysis of static and time resolved photoluminescence spectra. → Codoping with Li + ions leads to about twice enhancement of the near-infrared luminescence intensity around 1 μm at room temperature. - Abstract: Intense near-infrared emission at 1 μm has been obtained in ZnO-SiO 2 :Yb 3+ composites via a facile sol-gel method upon broadband ultraviolet light excitation. Systematic optical measurements including static and time-resolved photoluminescence have been performed to elucidate the energy transfer from ZnO quantum dots to Yb 3+ ions. The dependence of energy transfer efficiency on Yb 3+ concentration has been investigated in detail. Codoping with Li + ions leads to about twice enhancement of the near-infrared luminescence intensity around 1 μm at room temperature. The enhancement in the luminescence intensity could be mostly attributed to the modification of the local symmetry around Yb 3+ ions by codoping with Li + ions.

  9. Sol-Gel Derived Active Material for Yb Thin-Disk Lasers.

    Science.gov (United States)

    Almeida, Rui M; Ribeiro, Tiago; Santos, Luís F

    2017-09-02

    A ytterbium doped active material for thin-disk laser was developed based on aluminosilicate and phosphosilicate glass matrices containing up to 30 mol% YbO 1.5 . Thick films and bulk samples were prepared by sol-gel processing. The structural nature of the base material was assessed by X-ray diffraction and Raman spectroscopy and the film morphology was evidenced by scanning electron microscopy. The photoluminescence (PL) properties of different compositions, including emission spectra and lifetimes, were also studied. Er 3+ was used as an internal reference to compare the intensities of the Yb 3+ PL peaks at ~ 1020 nm. The Yb 3+ PL lifetimes were found to vary between 1.0 and 0.5 ms when the Yb concentration increased from 3 to 30 mol%. Based on a figure of merit, the best active material selected was the aluminosilicate glass composition 71 SiO₂-14 AlO 1.5 -15 YbO 1.5 (in mol%). An active disk, ~ 36 μm thick, consisting of a Bragg mirror, an aluminosilicate layer doped with 15 mol% Yb and an anti-reflective coating, was fabricated.

  10. Diode-pumped Yb:Sr5(PO4)3F laser performance

    International Nuclear Information System (INIS)

    Marshall, C.D.; Payne, S.A.; Smith, L.K.

    1995-01-01

    The performance of the first diode-pumped Yb 3+ -doped Sr 5 (PO 4 ) 3 F (Yb:S-FAP) laser is discussed. We found the pumping dynamics and extraction cross-sections of Yb:S-FAP crystals to be similar to those previously inferred by purely spectroscopic techniques. The saturation fluence for pumping was measured to be 2.2 J/cm 2 using three different methods based on either the spatial, temporal, or energy transmission properties of a Yb:S-FAP rod. The small signal gain implies an emission cross section of 6.0 x 10 -20 cm 2 that falls within error bars of the previously reported value of 7.3 x 10 -20 cm 2 , obtained from spectroscopic techniques. Up to 1.7 J/cm 3 of stored energy density was achieved in a 6 x 6 x 44 mm Yb:S-FAP amplifier rod. An InGaAs diode array has been fabricated that has suitable specifications for pumping a 3 x 3 x 30 mm Yb:S-FAP rod. In a free running configuration diode-pumped slope efficiencies up to 43% were observed with output energies up to ∼0.5 J per 1 ms pulse. When the rod was mounted in a copper block for cooling, 13 W of average power was produced with power supply limited operation at 70 Hz and 500 μs pulses

  11. Coexistence of metallic and insulating channels in compressed YbB6

    Science.gov (United States)

    Ying, Jianjun; Tang, Lingyun; Chen, Fei; Chen, Xianhui; Struzhkin, Viktor V.

    2018-03-01

    It remains controversial whether compressed YbB6 material is a topological insulator or a Kondo topological insulator. We performed high-pressure transport, x-ray diffraction (XRD), x-ray absorption spectroscopy, and Raman-scattering measurements on YbB6 samples in search for its topological Kondo phase. Both high-pressure powder XRD and Raman measurements show no trace of structural phase transitions in YbB6 up to 50 GPa. The nonmagnetic Yb2 + gradually change to magnetic Yb3 + above 18 GPa concomitantly with the increase in resistivity. However, the transition to the insulating state occurs only around 30 GPa, accompanied by the increase in the shear stress, and anomalies in the pressure dependence of the Raman T2 g mode and in the B atomic position. The resistivity at high pressures can be described by a model taking into account coexisting insulating and metallic channels with the activation energy for the insulating channel about 30 meV. We argue that YbB6 may become a topological Kondo insulator at high pressures above 35 GPa.

  12. Investigation of Anderson lattice behavior in Yb1-xLuxAl3

    International Nuclear Information System (INIS)

    Bauer, E.D.; Booth, C.H.; Lawrence, J.M.; Hundley, M.F.; Sarrao, J.L.; Thompson, J.D.; Riseborough, P.S.; Ebihara, T.

    2003-01-01

    Measurements of magnetic susceptibility χ(T), specific heat C(T), Hall coefficient R H (T), and Yb valence ν = 2 + n f [f-occupation number n f (T) determined from Yb L 3 x-ray absorption measurements] were carried out on single crystals of Yb 1-x Lu x Al 3 . The low temperature anomalies observed in χ(T) and C(T) corresponding to an energy scale T coh ∼ 40 K in the intermediate valence, Kondo lattice compound YbAl 3 are suppressed by Lu concentrations as small as 5% suggesting these low-T anomalies are extremely sensitive to disorder and, therefore, are a true coherence effect. By comparing the temperature dependence of various physical quantities to the predictions of the Anderson Impurity Model, the slow crossover behavior observed in YbAl 3 , in which the data evolve from a low-temperature coherent, Fermi-liquid regime to a high temperature local moment regime more gradually than predicted by the Anderson Impurity Model, appears to evolve to fast crossover behavior at x ∼ 0.7 where the evolution is more rapid than predicted. These two phenomena found in Yb 1-x Lu x Al 3 , i.e., the low-T anomalies and the slow/fast crossover behavior are discussed in relation to recent theories of the Anderson lattice

  13. Preparation and radiopharmaceutical control of 169Yb EDTA an agent for kidney function and scintigraphy

    International Nuclear Information System (INIS)

    Gulbaba, G.; Ozker; Tomek, F.

    1976-01-01

    169 Yb was produced by thermal neutron irradiation of Yb 2 O 3 in 1 MW research reactor at Cekmece Nuclear Research Center. 169 Yb-EDTA complex was then prepared with a sodium salt of EDTA. Radionuclidic and radiochemical purities of the compound were determined by gama spectral analysis and radiochromatography-electrophoresis following preparation. Ionic Yb(III) which accumulates at bone and liver was not observed on the radiochromatographic and electrophoretic analysis of the final compound. There was no separation of the label for two months of examination in order to determine stability of the compound. In conclusion, the labeled compound has been prepared for use in the external scanning of kidney and determining the glomerular filtration rate. The label appears to be firmly bound so that the agent can be stored for a reasonably long period as 31 days half-life of 169 Yb permits. Administration of the compound is safe from the stand point of radiation dose since a 30 micro-Ci 169 Yb-EDTA for a glomerular filtration study delivers no more than 0.4 mrad whole-body and 5 mrad kidney dose. (author)

  14. Evaluation von Bildungssoftware im Spannungsfeld von Objektivität und praktischer Anwendung

    Directory of Open Access Journals (Sweden)

    Cornelia Biffi

    2002-05-01

    Full Text Available Das Angebot an Bildungs- bzw. Lernsoftware umfasst eine breite Palette von sehr unterschiedlichen Produkten. Eigentliche Unterrichtssoftware, die speziell für den Unterricht hergestellt und auf Lehrmittel und Curriculum abgestimmt ist, gibt es kaum. Im Projekt «Lernsoftware Evaluation» des Pestalozzianums Zürich ermitteln Lehrpersonen die Qualität von Bildungssoftware, indem sie diese im Unterricht einsetzen und anhand eines Kriterienrasters beurteilen. Eine Analyse der in der Evaluation generierten Daten belegt die Problematik des Anspruchs einer objektiven Qualitätsbeurteilung. Es werden die Probleme bei der Anwendung von Kriterienraster und Beurteilungsmodus aufgezeigt und ermittelt, worin die subjektiven Qualitätsmassstäbe der Evaluierenden begründet sind. Diese Ausführungen sind Teil eines Forschungsprojekts für die Weiterentwicklung einer theoretisch fundierten, aber dennoch praxisnahen Evaluation von Bildungssoftware.

  15. Von der Medienwirkungsbehauptung zur erziehungswissenschaftlichen Medienrezeptionsforschung. Vorschlag zur Analyse von Filmkommunikaten

    Directory of Open Access Journals (Sweden)

    Barbara Drinck

    2001-04-01

    Full Text Available Im Hinblick auf die Erforschung spezifischer Zusammenhänge von Medienkonsum und der Herausbildung von Einstellungen und Handlungen wird eine konstruktivistische Theorieorientierung plausibilisiert, indem zunächst auf den Stand der Medienwirkungsforschung eingegangen und vor dem Hintergrund einer begründeten Kritik des Wirkungsverständnisses auf die Notwendigkeit einer medienrezeptionswissenschaftlichen Forschungsalternative hingewiesen wird. Weiterhin wird der Stand der (erziehungswissenschaftlichen Medienrezeptionsforschung erörtert. Sodann werden Elemente einer konstruktivistischen Methodologie von Medienrezeptionsforschung beschrieben, die am Beispiel der Rezeption von Filmen konkretisiert werden. Dabei wird das Konzept des Kommunikates (S.J. Schmidt als Ausgangspunkt genommen, ein Vorschlag für eine Beschreibungssprache für (Film- Kommunikate entwickelt und eine Adaption des Ansatzes filmischer Narration zur Sprache gebracht.

  16. Erzeugung gleichverteilter Stichproben von Lozenge-Teilungen mittels Kopplung von Markovketten

    OpenAIRE

    Keller, Peter

    2011-01-01

    Aus dem Inhalt: 1 Einleitung 2 Eigenschaften der Lozengeteilungen 3 Coupling From The Past (CFTP) 4 Simulation von uniform verteilten Lozengeteilungen 5 Programmlisting und Diskussion der Implementierung 6 Ausblick A Anhang

  17. Der Briefwechsel zwischen Alexander von Humboldt und Karl Ernst von Baer

    Directory of Open Access Journals (Sweden)

    Thomas Schmuck

    2012-10-01

    Full Text Available Zusammenfassung Der kurze, nicht vollständig erhaltene Briefwechsel zwischen Alexander von Humboldt und Karl Ernst von Baer behandelt sehr verschiedene Themen: Politik, Kriegsgefahr, den Wissenschaftsbetrieb, Auszeichnungen und Tagungen, Embryologie und Cholera. Gemeinsam mit Briefen und Reden ergibt sich dabei ein differenziertes Bild der Beurteilung der beiden Wissenschaftler durch den jeweils anderen. Während Baer sich als Bewunderer Humboldts erweist, erscheint umgekehrt Humboldts Einschätzung Baers als ambivalent. Abstract The short, not completely preserved correspondence between Alexander von Humboldt and Karl Ernst von Baer deals with a wide range of subjects: politics and the danger of war, academic activities, scientific awards and conferences, aspects of embryology and the cholera. Letters to third persons and speeches, together with the correspondence between Humboldt and Baer show a differentiated pattern of mutual appraisal: While Baer always remained an admirer of the elder naturalist, Humboldt’s estimation was characterized by ambivalence.

  18. Growth and continuous-wave laser operation of disordered crystals of Yb3+:NaLa(WO4)2 and Yb3+:NaLa(MoO4)2

    Science.gov (United States)

    Liu, J.; Cano-Torres, J. M.; Cascales, C.; Esteban-Betegón, F.; Serrano, M. D.; Volkov, V.; Zaldo, C.; Rico, M.; Griebner, U.; Petrov, V.

    2005-03-01

    Single crystals of disordered NaLa(WO4)2 and NaLa(MoO4)2 doped with Yb3+ are grown by the Czochralski method from the melt. Continuous-wave laser operation with Ti:sapphire laser pumping is demonstrated at room temperature without special cooling. Tunability from 1017 to 1057 nm and from 1015 to 1053 nm is achieved for Yb:NaLa(WO4)2 and Yb:NaLa(MoO4)2, respectively. A maximum output power of 205 mW is obtained with Yb:NaLa(WO4)2.

  19. Untersuchungen zur Entwicklung von Satellitengalaxien

    Science.gov (United States)

    Seidel, Björn

    2002-01-01

    Gleichgewichtsmodelle ein- und zweikomponentiger Satellitengalaxien werden erzeugt und die Gezeiteneinwirkungen der als starres äußeres Potential angenommenen Milchstraße auf sie betrachtet. Eine erste Reihe von Simulationen mit anfänglich kugelsymmetrischen einkomponentigen Satelliten zeigt, daß sich nach elliptischer Deformation ein Balken und Schweife ungleicher Länge ausbilden, deren Aussehen sich periodisch ändert. Mithilfe von Vergleichssimulationen wurden folgende Phänomene am Satelliten entdeckt: (1) Hochdichtebereiche in den Schweifen, (2) Niedrigdichtebereiche um den Kern bzw. Balken und (3) ein oft verdeckter Balken. Analysiert wird das Erscheinungsbild in Zeitabhängigkeit. Die Teilchen gehen dem Kern über den Balken verloren und bewegen sich entlang gewisser stets gleich aussehender charakteristischer Strukturen in die Schweife. Nach einer Herleitung allgemeiner Größen des mehrkomponentigen Kingprofils werden drei stabile Standardmodelle zweikomponentiger Satellitengalaxien mit Massenverhältnis 1:10 (baryonische zu dunkle Materie) und unterschiedlicher Verteilung der dunklen und sichtbaren Materie gefunden. Ohne die Allgemeinheit der Ergebnisse zu beeinträchtigen, wurde dabei die Große Magellanische Wolke als Grundlage der Modelle genommen. Nach geeigneter Wahl der Bahn, zu der der Gezeitenradius des verwendeten dreikomponentigen Milchstraßenpotentials sowohl analytisch als auch numerisch berechnet wird, werden Simulationen der Modelle analysiert. Hauptaugenmerk ist das unterschiedliche Verhalten der Komponenten. Hauptergebnisse: (1) Es ist möglich, große Anteile dunkler, jedoch nur geringe sichtbarer Materie abzulösen. Dunkle und sichtbare Materie können unterschiedliche morphologische Strukturen bilden. (2) Je nach Konzentration der Komponenten ist die Eigengravitation der Teilchen mehr oder weniger für das Aussehen bestimmend. (3) Die Kernauflösung des Satelliten findet im Perigalaktikum (PG), sein Zerfall aber erst im

  20. A note on derivations of Murray–von Neumann algebras

    Science.gov (United States)

    Kadison, Richard V.; Liu, Zhe

    2014-01-01

    A Murray–von Neumann algebra is the algebra of operators affiliated with a finite von Neumann algebra. In this article, we first present a brief introduction to the theory of derivations of operator algebras from both the physical and mathematical points of view. We then describe our recent work on derivations of Murray–von Neumann algebras. We show that the “extended derivations” of a Murray–von Neumann algebra, those that map the associated finite von Neumann algebra into itself, are inner. In particular, we prove that the only derivation that maps a Murray–von Neumann algebra associated with a factor of type II1 into that factor is 0. Those results are extensions of Singer’s seminal result answering a question of Kaplansky, as applied to von Neumann algebras: The algebra may be noncommutative and may even contain unbounded elements. PMID:24469831

  1. A note on derivations of Murray-von Neumann algebras.

    Science.gov (United States)

    Kadison, Richard V; Liu, Zhe

    2014-02-11

    A Murray-von Neumann algebra is the algebra of operators affiliated with a finite von Neumann algebra. In this article, we first present a brief introduction to the theory of derivations of operator algebras from both the physical and mathematical points of view. We then describe our recent work on derivations of Murray-von Neumann algebras. We show that the "extended derivations" of a Murray-von Neumann algebra, those that map the associated finite von Neumann algebra into itself, are inner. In particular, we prove that the only derivation that maps a Murray-von Neumann algebra associated with a factor of type II1 into that factor is 0. Those results are extensions of Singer's seminal result answering a question of Kaplansky, as applied to von Neumann algebras: The algebra may be noncommutative and may even contain unbounded elements.

  2. Soolopartiid Von Krahli katuse all / Kristi Eberhart

    Index Scriptorium Estoniae

    Eberhart, Kristi

    2007-01-01

    Von Krahli Teatri kolmest lavastusest: "Erki ja Tiina" (lavastaja Mart Kangro, tantsivad Erki Laur ja Tiina Tauraite), "Faust" (J. W. Goethe ainetel tekst ja lavastus Taavi Eelmaa, muusika ja laulud Chalice, osades Jarek Kasar ja Rein Pakk), "Hamletid" (William Shakespeare'i ainetel kontseptsiooni, lavastuse, koreograafia, kujunduse, valguse autor Sasha Pepeljajev, video- ja helikunstnik Taavet Jansen. Esitaja Juhan Ulfsak)

  3. Alexander von Humboldt and Coenraad Jacob Temminck

    NARCIS (Netherlands)

    Raat, A.J.P.

    1976-01-01

    INTRODUCTION In the archives of the Rijksmuseum van Natuurlijke Historie in Leiden there is a map with three letters written by Alexander von Humboldt (17691859) to the first director of the Museum, Coenraad Jacob Temminck (1778-1858). The map, the hard cover of John Gould's "Synopsis of the birds

  4. Differential functional von Foerster equations with renewal

    Directory of Open Access Journals (Sweden)

    H.Leszczyński

    2008-06-01

    Full Text Available Natural iterative methods converge to the exact solution of a differential-functional von Foerster-type equation which describes a single population dependent on its past time and state densities as well as on its total size. On the lateral boundary we impose a renewal condition.

  5. Wege zur Entdeckung von Communities in Folksonomies

    OpenAIRE

    Jäschke, Robert; Hotho, Andreas; Schmitz, Christoph; Stumme, Gerd

    2006-01-01

    Ein wichtiger Baustein des neu entdeckten World Wide Web - des "Web 2.0" - stellen Folksonomies dar. In diesen Systemen können Benutzer gemeinsam Ressourcen verwalten und mit Schlagwörtern versehen. Die dadurch entstehenden begrifflichen Strukturen stellen ein interessantes Forschungsfeld dar. Dieser Artikel untersucht Ansätze und Wege zur Entdeckung und Strukturierung von Nutzergruppen ("Communities") in Folksonomies.

  6. Hans von Engel and the ICPIG Conference

    International Nuclear Information System (INIS)

    Franklin, R.

    2000-01-01

    The history of the, organized by Hans von Engel, International Conference on Phenomena in Ionized Gases is presented: Oxford (1953), Delft (1955), Venice (1957), Uppsala (1959), Munich (1961), Oxford (1971) and Berlin (1977). Some organizational aspects, financial support and remarkable events like international prizes in field of plasma physics are given

  7. Guido von Pirquet: Austrian pioneer of astronautics

    Science.gov (United States)

    Sykora, F.

    1977-01-01

    The works of Guido von Pirquet, Austrian pioneer of rocketry, were assessed. Major emphasis was given to Pirquet's calculation of the route to Venus which in fact was followed by the first Russian rocket to Venus. Of interest also is Pirquet's valuable construction of a space station and his analysis of interstellar space flight.

  8. Ueberreste vorweltlicher Proboscidier von Java und Banka

    NARCIS (Netherlands)

    Martin, K.

    1884-01-01

    Junghuhn führte in seinem Werke über Java nur einen einzigen Wirbelthierrest, Carcharias megalodon, an (7, IV, pag. 97); es war ihm nicht gelungen bei seinem ersten Aufenthalte auf der Insel Reste von Säugethieren zu finden, so eifrig er auch darnach in den Höhlen des Tertiaergebirges suchte (7, IV,

  9. Active Von Willebrand Factor, thrombocytopenia and thrombosis

    NARCIS (Netherlands)

    Hulstein, J.J.J.

    2006-01-01

    Platelets and von Willebrand factor (VWF) are unable to interact in circulation. To induce an interaction, a conversion of VWF to a platelet-binding conformation is required. At higher shear stresses, the first step in thrombus formation is binding of VWF to the subendothelium. This results in

  10. Ueber eine Anomalie von Acromitus flagellatus (Stiasny)

    NARCIS (Netherlands)

    Stiasny, G.

    1934-01-01

    Bei erneuter Durchsicht des reichhaltigen Materiales von Acromitus flagellatus (Stiasny) in der Scyphomedusen-Sammlung des Rijksmuseum van Natuurlijke Historie in Leiden (vergl. meine Mitteilungen daruber, 1920, Uebersichtstabelle III und 1921, p. 131/136) fand ich ein Exemplar, das eine

  11. Von Kalifornien nach Taxham / Katri Soe

    Index Scriptorium Estoniae

    Soe, Katri, 1971-

    2005-01-01

    Neljas osa magistritööst "Von Kalifornien nach Taxham: Formen und Strukturen der Kommunikation in Peter Handkes Romanen "Der kurze Brief zum langen Abschied" und "In einer dunklen Nacht ging ich aus meinem stillen Haus"" (Tartu, 2000. Juhendaja: Claus Sommerhage)

  12. Von der lernenden Region zur "Smart Region“

    OpenAIRE

    Poschwatta, Wolfgang

    2004-01-01

    Von der lernenden Region zur "Smart Region“ / M. Hilpert, W. Poschwatta. - In: Nabizadeh-Araghi, Nima : Auf dem Weg zur "Smart Region" : regionale Entwicklung am Beispiel der Pistazienproduktion im Iran. - Augsburg : Müllerdruck, 2004. - S. 5-9. - (Terra facta ; 2)

  13. Study of chromites YbMIICr2O5,5 (MII - Mg, Ca, Sr, Ba by X-ray diffraction

    Directory of Open Access Journals (Sweden)

    B. Kasenov

    2012-03-01

    Full Text Available Compounds of composition YbMeMnFeO5,5 (Me – Mg, Ca, Sr, Ba are synthesized from Yb2O3, , Cr2O3 and MgCO3, CaCO3, SrCO3, BaCO3 by solid phase method. X-ray powder diffraction showed that the compound YbMgCr2O5,5, YbCaCr2O5,5, YbSrCr2O5,5, YbBaCr2O5,5 crystallizes in the tetragonal crystal system.

  14. Spectroscopic properties and quenching processes of Yb{sup 3+} in Fluoride single crystals for laser applications

    Energy Technology Data Exchange (ETDEWEB)

    Bensalah, A. [Physical Chemistry of Luminescent Materials, Claude Bernard/Lyon1 University, UMR 5620, CNRS Bat. A. Kastler, 10 rue Ampere, 69622 Villeurbanne (France) and Institute for Multidisciplinary Research of Advanced Materials, Tohoku University, Sendai 980-8577 (Japan)]. E-mail: amina-bensalah@enscp.fr; Ito, M. [Physical Chemistry of Luminescent Materials, Claude Bernard/Lyon1 University, UMR 5620, CNRS Bat. A. Kastler, 10 rue Ampere, 69622 Villeurbanne (France); Guyot, Y. [Physical Chemistry of Luminescent Materials, Claude Bernard/Lyon1 University, UMR 5620, CNRS Bat. A. Kastler, 10 rue Ampere, 69622 Villeurbanne (France); Goutaudier, C. [Physical Chemistry of Luminescent Materials, Claude Bernard/Lyon1 University, UMR 5620, CNRS Bat. A. Kastler, 10 rue Ampere, 69622 Villeurbanne (France); Jouini, A. [Physical Chemistry of Luminescent Materials, Claude Bernard /Lyon1 University, UMR 5620, CNRS Bat. A. Kastler, 10 rue Ampere, 69622 Villeurbanne (France); Institute for Multidisciplinary Research of Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Brenier, A. [Physical Chemistry of Luminescent Materials, Claude Bernard/Lyon1 University, UMR 5620, CNRS Bat. A. Kastler, 10 rue Ampere, 69622 Villeurbanne (France); Sato, H. [Institute for Multidisciplinary Research of Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Fukuda, T. [Institute for Multidisciplinary Research of Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Boulon, G. [Physical Chemistry of Luminescent Materials, Claude Bernard /Lyon1 University, UMR 5620, CNRS Bat. A. Kastler, 10 rue Ampere, 69622 Villeurbanne (France)

    2007-01-15

    Spectroscopic characterization is carried out to identify Stark's levels of Yb{sup 3+} transitions in several fluoride crystals grown either by the Czochralski technique or by the laser-heated pedestal growth method. Yb{sup 3+} concentration dependence of the decay time is analyzed in order to understand involved concentration quenching mechanisms. Laser tests under saphire:Ti pumping are presented for all our materials as well as under diode pumping for Yb:CaF{sub 2}.

  15. Electronic structure and X-ray spectroscopic properties of YbNi{sub 2}P{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Shcherba, I.D., E-mail: ishcherba@gmail.com [Institute of Technology, University of Pedagogy, Podchorazych 2, 30-084 Krakow (Poland); Lviv National University by Ivan Franko, Lviv (Ukraine); Bekenov, L.V.; Antonov, V.N. [Institute for Metal Physics, 36 Vernadsky Street, 03142 Kiev (Ukraine); Noga, H. [Institute of Technology, University of Pedagogy, Podchorazych 2, 30-084 Krakow (Poland); Uskokovic, D. [Institute of Technical Sciences, SASA, Belgrade (Serbia); Zhak, O.; Kovalska, M.V. [Lviv National University by Ivan Franko, Lviv (Ukraine)

    2016-10-15

    Highlights: • We present new experimental and theoretical data for YbNi{sub 2}P{sub 2}. • The presence of divalent and trivalent Yb ion found in YbNi{sub 2}P{sub 2}. • The calculation show good agreement with the experimental measurements. - Abstract: X-ray absorption spectrum at the Yb L{sub 3} edge and X-ray emission spectra of Ni and P at the K and L{sub 2,3} edges have been studied experimentally and theoretically in the mixed valent compound YbNi{sub 2}P{sub 2} with ThCr{sub 2}Si{sub 2} type crystal structure. The electronic structure of YbNi{sub 2}P{sub 2} is investigated using the fully relativistic Dirac linear muffin-tin orbital (LMTO) band-structure method. The effect of the spin–orbit (SO) interaction and Coulomb repulsion U on the electronic structure of YbNi{sub 2}P{sub 2} is examined in the frame of the LSDA + SO + U method. The core-hole effect in the final states as well as the effect of the electric quadrupole E{sub 2} transitions have been investigated. A good agreement between the theory and the experiment was found. Both the trivalent and the divalent Yb ions in YbNi{sub 2}P{sub 2} are reflected in the experimentally measured Yb L{sub 3} X-ray absorption spectrum simultaneously. We found that the best agreement between the experimental spectrum and sum of the theoretically calculated Yb{sup 2+} and Yb{sup 3+} spectra is achieved with 73% ytterbium ions in 2+ state and 27% ions in 3+ state.

  16. HoYbBIG epitaxial thick films used for Faraday rotator in the 1.55μm band

    International Nuclear Information System (INIS)

    Zhong, Z.W.; Xu, X.W.; Chong, T.C.; Yuan, S.N.; Li, M.H.; Zhang, G.Y.; Freeman, B.

    2005-01-01

    Ho 3-x-y Yb y Bi x Fe 5 O 12 (HoYbBIG) garnet thick films with Bi content of x=0.9-1.5 were prepared by the liquid phase epitaxy (LPE) method. Optical properties and magneto-optical properties were characterized. The LPE-grown HoYbBIG thick films exhibited large Faraday rotation coefficients up to 1540 o /cm at 1.55μm, and good wavelength and temperature stability

  17. The physical and chemical characteristics of 175Yb-EDTMP labelled compound

    International Nuclear Information System (INIS)

    Azmairit Aziz; Marlina; Muhammad Basit Febrian

    2010-01-01

    Bone pain is a common complication for patient with bone metastases from breasts, prostate and lung cancers. The derivative of phosphonate groups, i.e. diphosphonate as well as poly phosphonate ligands e.g. EDTMP have high affinity in bone matrix. The labeled compound of 175 Yb-EDTMP can be used as an alternative radiopharmaceutical for bone pain palliation. The compound of 175 Yb-EDTMP can be produced by labeling of ethylenediamine tetramethylene phosphonic acid (EDTMP) with itterbium-175 ( 175 YbCl 3 ). Before 175 Yb-EDTMP is used for bone pain palliation in nuclear medicine, the compound have to be characterized to full fill the criteria of the good radiopharmaceutical. The physical and chemical characteristics of 175 Yb-EDTMP had been studied. It consists of: pH, solution clearity, the radiochemical purity that was determined by paper chromatography and paper electrophoresis techniques, electricity charge was determined by paper electrophoresis, stability, lipophilicity of 175 Yb-EDTMP was obtained by determination of octanol-water partition and the plasma binding protein was in-vitro investigated with precipitation method using 5% of trichloroacetic acid solution, and the binding to hydroxyapatite. From the experiment, it was obtained that the 175 Yb-EDTMP solution has the pH of 7, clear, the radiochemical purity of 98.66 ± 0.53%, and the negative electric charge. The compound of 175 Yb-EDTMP has lipophilicity (P) of 0.0135 ± 0.003%, the human plasma binding protein of 8.94 ± 0.66%, and the hydroxyapatite binding of 94.78 ± 2.16%. Stability evaluation indicated that 175 Yb-EDTMP solution was still stable for nine days at room temperature with the radiochemical purity more than 95% (98.62 ± 0.83%). This study expects that 175 Yb-EDTMP compound can fulfill the requirement as radiopharmaceutical for use in palliative treatment of painful bone metastases and supports the development of nuclear medicine in Indonesia. (author)

  18. Affinity of 169Yb, 67Ga and 111In for malignant tumor, (1)

    International Nuclear Information System (INIS)

    Ando, Itsuko

    1975-01-01

    The tumor affinity of 169 Yb-citrate, 67 Ga-citrate and 111 In-citrate was examined by using Yoshida sarcoma-bearing rats, and the affinity of these compounds for inflammation was also tested using rats with inflammation induced by croton oil injection. In this investigation there was no great difference in uptake by the tumor tissue of these compounds, but a great difference was observed in the retention value of the blood and uptake rate in the bone. 169 Yb-citrate was cleared rapidly from the blood and was taken mostly into the bone. So the retention values in the soft tissues became very small. On the other hand, 111 In-citrate was slowly and only slightly taken into the bone from the blood, so the retention values in the soft tissue remained relatively high. 67 Ga-citrate showed the intermediate value between the bone uptake rate of 169 Yb-citrate and that of 111 In-citrate. In the following experiments, 169 Yb-citrate and 67 Ga-citrate were compared in four strains: Yoshida sarcoma, Walker carcinosarcoma 256, Sarcoma 180, and Ehrlich tumor. The uptake rate of 169 Yb in tumor tissue was much larger than that of 67 Ga in Ehrlich tumor-bearing mice, but the value of 169 Yb was slightly smaller than those of 67 Ga in Yoshida sarcoma-bearing rats, Walker carcinosarcoma 256-bearing rats and Sarcoma 180-bearing mice. Tumor to organ ratios of 169 Yb, which were most important for tumor scanning, were much larger than those of 67 Ga in all four strains except tumor to bone ratios of 169 Yb. From the above-described facts, it was shown that 169 Yb-citrate had a stronger tumor affinity than 67 Ga-citrate and that the tumor affinity of 169 Yb-citrate was similar in these four strains of tumor bearing animals. These three compounds had a relatively strong affinity with the inflammatory tissue. (auth.)

  19. Electronic structure of YbNiX{sub 3} (X =Si, Ge) studied by hard X-ray photoemission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Hitoshi; Shimada, Kenya; Namatame, Hirofumi [Hiroshima Synchrotron Radiation Center, Hiroshima University, Kagamiyama 2-313, Higashi-Hiroshima 739-0046 (Japan); Utsumi, Yuki [Max-Planck Institute for Chemical Physics of Solids, 01187 Dresden (Germany); Kodama, Junichi; Nagata, Heisuke [Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan); Avila, Marcos A.; Ribeiro, Raquel A. [Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, Santo Andre - SP, 09210-580 (Brazil); Umeo, Kazunori [Cryogenics and Instrumental Analysis Division, N-BARD, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan); Takabatake, Toshiro [Department of Quantum Matter, AdSM, Hiroshima University, Higashi-Hiroshima 739-8530 (Japan); Institute for Advanced Materials Research, Hiroshima University, Higashi-Hiroshima 739-8530 (Japan); Mimura, Kojiro; Motonami, Satoru; Anzai, Hiroaki [Graduate School of Engineering, Osaka Prefecture University, Sakai 599-8531 (Japan); Ueda, Shigenori [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science, Hyogo 679-5148 (Japan); Taniguchi, Masaki [Hiroshima Synchrotron Radiation Center, Hiroshima University, Kagamiyama 2-313, Higashi-Hiroshima 739-0046 (Japan); Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan)

    2015-06-15

    lectronic structure of the Kondo lattices YbNiX{sub 3} (X =Si, Ge) has been investigated by means of hard x-ray photoemission spectroscopy (HAXPES) with hν = 5.95 keV. From the Yb 3d HAXPES spectra, the Yb valence in YbNiSi{sub 3} is estimated to be ∝ 2.92, which is almost temperature-independent. On the other hand, the valence in YbNiGe{sub 3} is estimated to be 2.48 at 300 K, showing significant valence fluctuation, and gradually decreases to 2.41 at 20 K on cooling. The Ni 2p{sub 3/2} and Yb{sup 3+} 4f peaks exhibit opposite energy shifts amounting to ∝ 0.6 eV between YbNiSi{sub 3} and YbNiGe{sub 3}. We propose a simple model for the electronic structure of YbNiX{sub 3} based on the HAXPES results. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Radio metal (169Yb) uptake in normal and tumour cells in vitro. Influence of metabolic cell activity and complex structure

    International Nuclear Information System (INIS)

    Franke, W.G.; Kampf, G.

    1996-01-01

    Trivalent radio metal tracers have been used for tumour imaging and metastatic pain palliation. For better understanding their tumour accumulation, basic model studies of uptake of different 169 Yb complexes into cultured normal and tumour cells were performed. Whereas the uptake of 169 Yb citrate is strongly dependent on the metabolic activity and is not tumour-cell pacific, the uptake of 169 Yb complexed with amino carbonic acid (NTA, EDTA, DTPA) does not correlate to the metabolic activities. These complexes are taken up to a greater amount by the tumour cells (by a factor of about 2). Uptake of both complex types leads to a stable association to cellular compounds, 169 Yb is not releasable by the strong complexing agent DTPA. Protein binding of the 169 Yb complexes shows great influence on their cellular uptake. The bound proportion is no more available,for cellular uptake. The results indicate that i 0 uptake of 169 Yb citrate is an active cellular transport process which i not tumor-specific, ii) the 169 Yb amino carbonic acid complexes show a weak favouring by the tumour cells, iii) different from earlier acceptions the Yb complexes studied are not taken up by the cells in protein-bound form. The structure of the Yb complex is decisive for its protein binding and cellular uptake. (author). 13 refs., 6 figs

  1. Comparison of radiation shielding requirements for HDR brachytherapy using 169Yb and 192Ir sources

    International Nuclear Information System (INIS)

    Lymperopoulou, G.; Papagiannis, P.; Sakelliou, L.; Georgiou, E.; Hourdakis, C. J.; Baltas, D.

    2006-01-01

    169 Yb has received a renewed focus lately as an alternative to 192 Ir sources for high dose rate (HDR) brachytherapy. Following the results of a recent work by our group which proved 169 Yb to be a good candidate for HDR prostate brachytherapy, this work seeks to quantify the radiation shielding requirements for 169 Yb HDR brachytherapy applications in comparison to the corresponding requirements for the current 192 Ir HDR brachytherapy standard. Monte Carlo simulation (MC) is used to obtain 169 Yb and 192 Ir broad beam transmission data through lead and concrete. Results are fitted to an analytical equation which can be used to readily calculate the barrier thickness required to achieve a given dose rate reduction. Shielding requirements for a HDR brachytherapy treatment room facility are presented as a function of distance, occupancy, dose limit, and facility workload, using analytical calculations for both 169 Yb and 192 Ir HDR sources. The barrier thickness required for 169 Yb is lower than that for 192 Ir by a factor of 4-5 for lead and 1.5-2 for concrete. Regarding 169 Yb HDR brachytherapy applications, the lead shielding requirements do not exceed 15 mm, even in highly conservative case scenarios. This allows for the construction of a lead door in most cases, thus avoiding the construction of a space consuming, specially designed maze. The effects of source structure, attenuation by the patient, and scatter conditions within an actual treatment room on the above-noted findings are also discussed using corresponding MC simulation results

  2. Evolution of magnetic properties and exchange interactions in Ru doped YbCrO3

    International Nuclear Information System (INIS)

    Dalal, Biswajit; Sarkar, Babusona; De, S K; Dev Ashok, Vishal

    2016-01-01

    Magnetic properties of YbCr 1−x Ru x O 3 as a function of temperature and magnetic field have been investigated to explore the intriguing magnetic phenomena in rare-earth orthochromites. A quantitative analysis of x-ray photoelectron spectroscopy confirms the mixed valence state (Yb 3+  and Yb 2+ ) of Yb ions for the highest doped sample. Field-cooled magnetization reveals a broad peak around 75 K and then becomes zero at about 20–24 K, due to the antiparallel coupling between Cr 3+ and Yb 3+ moments. An increase of the Ru 4+ ion concentration leads to a slight increase of compensation temperature T comp from 20 to 24 K, but the Néel temperature remains constant. A larger value of the magnetic moment of Yb ions gives rise to negative magnetization at low temperature. An external magnetic field significantly modifies the temperature dependent magnetization. Simulation of temperature dependent magnetization data, below T N , based on the three (two) magnetic sub-lattice model predicts stronger intra-sublattice exchange interaction than that of inter-sublattice. Thermal hysteresis and Arrot plots suggest first order magnetic phase transition. Random substitution of Ru 4+ ion reduces the magnetic relaxation time. Weak ferromagnetic component in canted antiferromagnetic system and negative internal magnetic field cause zero-field-cooled exchange bias effect. Large magnetocrystalline anisotropy associated with Ru creates high coercivity in the Ru doped sample. A maximum value of magnetocaloric effect is found around the antiferromagnetic ordering of Yb 3+ ions. Antiferromagnetic transition at about 120 K and temperature induced magnetization reversal lead to normal and inverse magnetocaloric effects in the same material. (paper)

  3. Photoluminescence characterization of porous YAG: Yb{sup 3+}–Er{sup 3+} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Desirena, H., E-mail: hagdes@cio.mx [Centro de Investigaciones en Óptica, A. P. 1-948, León 37150, Guanajuato (Mexico); Diaz-Torres, L.A. [Centro de Investigaciones en Óptica, A. P. 1-948, León 37150, Guanajuato (Mexico); Rodríguez, R.A. [Centro Universitario de Los Lagos, Universidad de Guadalajara, Lagos de Moreno, Jalisco (Mexico); Meza, O. [Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apartado Postal J-48, Centro Historico 72570, Puebla (Mexico); Salas, P. [Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Apartado Postal 1-1010, Querétaro 76000, Querétaro México (Mexico); Angeles-Chávez, C. [Instituto Mexicano del Petróleo, Ciudad México, D.F. 07730, México (Mexico); Tobar, E.H.; Castañeda-Contreras, J. [Centro Universitario de Los Lagos, Universidad de Guadalajara, Lagos de Moreno, Jalisco (Mexico); De la Rosa, E., E-mail: elder@cio.mx [Centro de Investigaciones en Óptica, A. P. 1-948, León 37150, Guanajuato (Mexico)

    2014-09-15

    Yb{sup 3+}/Er{sup 3+} codoped yttrium aluminium garnet (YAG) porous nanocrystals were prepared by glycolate method assisted with poly-vinyl alcohol (PVA) and urea. The typical cubic structure for YAG was confirmed from XRD with crystallite average size of ∼40 nm, calculated from Scherrer formula and corroborated by TEM. Strong green and red upconversion emissions are observed readily with the naked eyes, and the color coordinates were obtained from emission spectra. A theoretical model to calculate CIE coordinate as a function of donor (Yb{sup 3+}) and acceptors (Er{sup 3+}) concentration is proposed. The eye-safe near infrared emitted signal and fluorescence lifetime were also measured and results show lifetime as large as 8.5 ms. The maximum energy transfer efficiency from Yb{sup 3+} to Er{sup 3+} was 72% for 20 mol% of Yb{sub 2}O{sub 3}. The proposed mechanisms for signal emitted are explained in terms of direct and energy back transfer processes, and cross relaxation. - Highlights: • Strong upconversion emission were observed in YAG:Er{sup 3+}–Yb{sup 3+} samples. • Color emission can be tuned from green to red by choosing properly the Yb{sup 3+} concentration. • The experimental colour coordinates match very well with the proposed theoretical model. • Cross relaxation and energy back transfer are mainly responsible for the red emission. • Fluorescence lifetime of {sup 4}I{sub 13/2} level increase with the Yb{sup 3+} concentration.

  4. Dependence of upconversion emission intensity on Yb3+ concentration in Er3+/Yb3+ co-doped flake shaped Y2(MoO4)3 phosphors

    International Nuclear Information System (INIS)

    Lu Weili; Cheng Lihong; Zhong Haiyang; Sun Jiashi; Wan Jing; Tian Yue; Chen Baojiu

    2010-01-01

    Yttrium molybdate phosphors with fixed Er 3+ and various Yb 3+ concentrations were synthesized via a co-precipitation method. The crystal structure and the morphology of the phosphor were characterized by means of x-ray diffraction and field-emission scanning electron microscopy. Under 980 nm excitation, red and green upconversion emissions centred at 660, 553 and 530 nm were observed. Quantitative analyses on the dependence of upconversion emission intensity on the working current of a laser diode (LD) indicated that two-photon processes are responsible for both red and green upconversion emissions in both cases of low and high Yb 3+ concentrations. The relationship between the emission intensity ratio of 2 H 11/2 → 4 I 15/2 to 4 S 3/2 → 4 I 15/2 and the working current of the LD was studied for the samples doped with low and high Yb 3+ concentrations. Finally, a set of rate equations was established based on the possible upconversion mechanism, and an empirical formula was proposed to describe the Yb 3+ concentration dependence of upconversion emission intensity; the empirical formula fits well with the experimental data.

  5. Dual functional NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+ core-shell nanoparticles for cell temperature sensing and imaging

    Science.gov (United States)

    Shi, Zengliang; Duan, Yue; Zhu, Xingjun; Wang, Qiwei; Li, DongDong; Hu, Ke; Feng, Wei; Li, Fuyou; Xu, Chunxiang

    2018-03-01

    Lanthanide-doped up-conversion nanoparticles (UCNPs) provide a remote temperature sensing approach to monitoring biological microenvironments. In this research, the UCNPs of NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+ with hexagonal (β)-phase were synthesized and applied in cell temperature sensing as well as imaging after surface modification with meso-2, 3-dimercaptosuccinic acid. In the core-shell UCNPs, Yb3+ ions were introduced as energy transfer media between sensitizers of Nd3+ and activators of Er3+ to improve Er3+emission and prevent their quenching behavior due to multiple energy levels of Nd3+. Under the excitations of 808 nm and 980 nm lasers, the NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+ nanoparticles exhibited an efficient green band with two emission peaks at 525 nm and 545 nm, respectively, which originated from the transitions of 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 for Er3+ ions. We demonstrate that an occurrence of good logarithmic linearity exists between the intensity ratio of these two emission peaks and the reciprocal of the inside or outside temperature of NIH-3T3 cells. A better thermal stability is proved through temperature-dependent spectra with a heating-cooling cycle. The obtained viability of NIH-3T3 cells is greater than 90% after incubations of about 12 and 24 (h), and they possess a lower cytotoxicity of UCNPs. This work provides a method for monitoring the cell temperature and its living state from multiple dimensions including temperature response, cell images and visual up-conversion fluorescent color.

  6. Thermodynamic properties of multiferroic Mg doped YbMnO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Sattibabu, Bhumireddi, E-mail: bsb.satti@gmail.com [School of Engineering Sciences and Technology, University of Hyderabad, Hyderabad 500046 (India); Bhatnagar, A.K., E-mail: anilb42@gmail.com [School of Engineering Sciences and Technology, University of Hyderabad, Hyderabad 500046 (India); School of Physics, University of Hyderabad, Hyderabad 500046 (India); Samatham, S. Shanmukharao; Singh, D. [Low Temperature Laboratory, UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, M.P. (India); Rayaprol, S. [UGC-DAE Consortium for Scientific Research, Mumbai Centre, BARC Campus, Mumbai 400085 (India); Das, D. [School of Engineering Sciences and Technology, University of Hyderabad, Hyderabad 500046 (India); Siruguri, V. [UGC-DAE Consortium for Scientific Research, Mumbai Centre, BARC Campus, Mumbai 400085 (India); Ganesan, V. [Low Temperature Laboratory, UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, M.P. (India)

    2015-09-25

    Highlights: • Specific heat data shows that T{sub N} increases for Mg doped YbMnO{sub 3} from 83 K to 86 K. • Yb{sub 1−x}Mg{sub x}MnO{sub 3} (x = 0.0 and 0.05) shows multiple magnetic transitions. • RCP are found to be 26.1 J/mol and 27.2 J/mol for YbMnO{sub 3} and Yb{sub 0.95}Mg{sub 0.05}MnO{sub 3}. - Abstract: Calorimetric studies of polycrystalline samples Yb{sub 1−x}Mg{sub x}MnO{sub 3} with x = 0.0 and 0.05 are reported. It is revealed that the Mg doping raises the antiferromagnetic ordering temperature, T{sub N,} from 83 K for x = 0.0 to 86 K for x = 0.05. A ferromagnetic ordering is also observed around 3 K. The broad feature in the specific heat data just above ferromagnetic ordering, is attributed to the Schottky anomaly. The estimated effective molecular fields from the Schottky analysis are H{sub mf} = 3.0 and 3.5 T for YbMnO{sub 3} and Yb{sub 0.95}Mg{sub 0.05}MnO{sub 3}, respectively. High temperature shift of Schottky anomaly with Mg doping indicates increase in effective molecular field of Mn at the Yb 4b site. The data supports that the idea that although molecular field is mainly responsible for the Schottky anomaly in Yb{sub 1−x}Mg{sub x}MnO{sub 3} and Mn{sup 3+} spin ordering also affects it. Magnetic part of the specific heat is obtained by subtracting the lattice contribution estimated using two Debye temperatures. The magnetic entropy change (ΔS{sub mag}) for pure and doped samples are 2.0 J mol{sup −1} K{sup −1} and 2.1 J mol{sup −1} K{sup −1} respectively, while the relative cooling power (RCP) calculate 26.1 J/mol, 27.2 J/mol for a field change of 10 T.

  7. Up-conversion luminescence of Er3+/Yb3+/Nd3+-codoped tellurite glasses

    International Nuclear Information System (INIS)

    Lu Longjun; Nie Qiuhua; Xu Tiefeng; Dai Shixun; Shen Xiang; Zhang Xianghua

    2007-01-01

    Up-conversion luminescence and energy transfer (ET) processes in Nd 3+ -Yb 3+ -Er 3+ triply doped TeO 2 -ZnO-Na 2 O glasses have been studied under 800 nm excitation. Intense green up-conversion emissions around 549 nm, which can be attributed to the Er 3+ : 4 S 3/2 →4 I 15/2 transition, are observed in triply doped samples. In contrast, the green emissions are hardly observed in Er 3+ singly doped and Er 3+ -Yb 3+ codoped samples under the same condition. Up-conversion luminescence intensity exhibits dependence of Yb 2 O 3 -concentration and Nd 2 O 3 -concentration. Up-conversion mechanism in the triply doped glasses under 800 nm pump is discussed by analyzing the ET among Nd 3+ , Yb 3+ and Er 3+ . And a possible up-conversion mechanism based on sequential ET from Nd 3+ to Er 3+ through Yb 3+ is proposed for green and red up-conversion emission processes

  8. Characterizations of Pr-doped Yb3Al5O12 single crystals for scintillator applications

    Science.gov (United States)

    Yoshida, Yasuki; Shinozaki, Kenji; Igashira, Takuya; Kawano, Naoki; Okada, Go; Kawaguchi, Noriaki; Yanagida, Takayuki

    2018-04-01

    Yb3Al5O12 (YbAG) single crystals doped with different concentrations of Pr were synthesized by the Floating Zone (FZ) method. Then, we evaluated their basic optical and scintillation properties. All the samples showed photoluminescence (PL) with two emission bands appeared approximately 300-500 nm and 550-600 nm due to the charge transfer luminescence of Yb3+ and intrinsic luminescence of the garnet structure, respectively. A PL decay profile of each sample was approximated by a sum of two exponential decay functions, and the obtained decay times were 1 ns and 3-4 ns. In the scintillation spectra, we observed emission peaks in the ranges from 300 to 400 nm and from 450 to 550 nm for all the samples. The origins of these emissions were attributed to charge transfer luminescence of Yb3+ and intrinsic luminescence of the garnet structure, respectively. The scintillation decay times became longer with increasing the Pr concentrations. Among the present samples, the 0.1% Pr-doped sample showed the lowest scintillation afterglow level. In addition, pulse height spectrum of 5.5 MeV α-rays was demonstrated using the Pr-doped YbAG, and we confirmed that all the samples showed a full energy deposited peak. Above all, the 0.1% Pr-doped sample showed the highest light yield with a value of 14 ph/MeV under α-rays excitation.

  9. Thermal and electron transport studies on the valence fluctuating compound YbNiAl4

    Science.gov (United States)

    Falkowski, M.; Kowalczyk, A.

    2018-05-01

    We report the thermoelectric power S and thermal conductivity κ measurements on the valence fluctuating compound YbNiAl4, furthermore taking into account the impact of the applied magnetic field. We discuss our new results with revisiting the magnetic [χ(T)], transport [ρ(T)], and thermodynamic [Cp(T)] properties in order to better understand the phenomenon of thermal and electron transport in this compound. The field dependence of the magnetoresistivity data is also given. The temperature dependence of thermoelectric power S(T) was found to exhibit a similar behaviour as expected for Yb-based compounds with divalent or nearly divalent Yb ions. In addition, the values of total thermal conductivity as a function of temperature κ(T) of YbNiAl4 are fairly low compared to those of pure metals which may be linked to the fact that the conduction band is perturbed by strong hybridization. A deeper analysis of the specific heat revealed the low-T anomaly of the ratio Cp(T)/T3, most likely associated with the localized low-frequency oscillators in this alloy. In addition, the Kadowaki-Woods ratio and the Wilson ratio are discussed with respect to the electronic correlations in YbNiAl4.

  10. Origin of quantum criticality in Yb-Al-Au approximant crystal and quasicrystal

    International Nuclear Information System (INIS)

    Watanabe, Shinji; Miyake, Kazumasa

    2016-01-01

    To get insight into the mechanism of emergence of unconventional quantum criticality observed in quasicrystal Yb 15 Al 34 Au 51 , the approximant crystal Yb 14 Al 35 Au 51 is analyzed theoretically. By constructing a minimal model for the approximant crystal, the heavy quasiparticle band is shown to emerge near the Fermi level because of strong correlation of 4f electrons at Yb. We find that charge-transfer mode between 4f electron at Yb on the 3rd shell and 3p electron at Al on the 4th shell in Tsai-type cluster is considerably enhanced with almost flat momentum dependence. The mode-coupling theory shows that magnetic as well as valence susceptibility exhibits χ ∼ T -0.5 for zero-field limit and is expressed as a single scaling function of the ratio of temperature to magnetic field T/B over four decades even in the approximant crystal when some condition is satisfied by varying parameters, e.g., by applying pressure. The key origin is clarified to be due to strong locality of the critical Yb-valence fluctuation and small Brillouin zone reflecting the large unit cell, giving rise to the extremely-small characteristic energy scale. This also gives a natural explanation for the quantum criticality in the quasicrystal corresponding to the infinite limit of the unit-cell size. (author)

  11. Bulk and surface electron transport in topological insulator candidate YbB{sub 6-δ}

    Energy Technology Data Exchange (ETDEWEB)

    Glushkov, Vladimir V.; Demishev, Sergey V.; Sluchanko, Nikolay E. [Prokhorov General Physics Institute of RAS, Vavilov str. 38, 119991, Moscow (Russian Federation); Moscow Institute of Physics and Technology, Institutskii per. 9, 141700, Dolgoprudny, Moscow Region (Russian Federation); Bozhko, Alexey D.; Bogach, Alexey V.; Semeno, Alexey V.; Voronov, Valeriy V. [Prokhorov General Physics Institute of RAS, Vavilov str. 38, 119991, Moscow (Russian Federation); Dukhnenko, Anatoliy V.; Filipov, Volodimir B.; Shitsevalova, Natalya Yu. [Frantsevich Institute for Problems of Materials Science NAS, Krzhyzhanovsky str. 3, 03680, Kiev (Ukraine); Kondrin, Mikhail V. [Vereshchagin Institute of High Pressure Physics of RAS, 142190, Troitsk, Moscow (Russian Federation); Kuznetsov, Alexey V.; Sannikov, Ilia I. [National Research Nuclear University ' ' MEPhI' ' , Kashirskoe Shosse 31, 115409, Moscow (Russian Federation)

    2016-04-15

    We report the study of transport and magnetic properties of the YbB{sub 6-δ}single crystals grown by inductive zone melting. A strong disparity in the low temperature resistivity, Seebeck and Hall coefficients is established for the samples with the different level of boron deficiency. The effective parameters of the charge transport in YbB{sub 6-δ} are shown to depend on the concentration of intrinsic defects, which is estimated to range from 0.09% to 0.6%. The pronounced variation of Hall mobility μ{sub H} found for bulk holes is induced by the decrease of transport relaxation time from τ ∼ 7.7 fs for YbB{sub 5.994} to τ ∼ 2.2 fs for YbB{sub 5.96}. An extra contribution to conductivity from electrons with μ{sub H}∼ -1000 cm{sup 2} V{sup -1} s{sup -1} and the very low concentration n /n{sub Yb}∼ 10{sup -6} discovered below 20 K for all the single crystals under investigation is suggested to arise from the surface electron states appeared in the inversion layer due to the band bending. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Yb3+:Sr5(VO4)3F: Crystal growth, spectroscopic characterization and laser development

    International Nuclear Information System (INIS)

    Bustamante, Andrea Nora Pino

    1999-01-01

    Crystal growth, spectroscopic characterization and laser development of Yb 3+ :SVAP [Sr 5 (VO 4 ) 3 F] was performed to demonstrate for the first time, operation of tunable laser emission centered at 1120 nm. Initially, SVAP crystals were grown with high dopant concentrations, up to 6.0 mol % of Yb 2 O 3 in the melt, in order to investigate the material for potential laser operation at a new laser wavelength. Additional research was performed to alleviate highly doped SVAP crystals of defects previously observed. Basic spectroscopic characterization including absorption and luminescent properties were measured to better understand the behavior of Yb 3+ ions in SVAP. Based upon these studies, discussion of the 1120 nm laser transition is presented as it arises from a ground state vibrational level. Investigations of the charge compensation process and the optical parameters as a function of dopant concentration are also presented. The laser development of Yb 3+ :SVAP included continuous and pulsed modes of operation of the 1044 nm and 1120 nm transitions. Initial laser action of the 1044 nm transition was achieved using a Yi: Saphire laser pump source in order to compare with previously results. Further development of a diode-pumped Yb 3+ :SVAP laser system demonstrated continuously tunable laser operation from 1103 nm for the first time. The laser investigations also proved that this high gain media does provide continuous wave laser action at 1044 nm and 1120 simultaneously without significant gain depletion. (author)

  13. Controllable synthesis and crystal structure determined upconversion luminescence properties of Tm{sup 3+} (Er{sup 3+}) ions doped YbF{sub 3} and NaYbF{sub 4} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Tao [Institute of Photonics, Faculty of Science, Ningbo University, Ningbo 315211 (China); Qin, Weiping, E-mail: wpqin@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Zhou, Jun [Institute of Photonics, Faculty of Science, Ningbo University, Ningbo 315211 (China)

    2014-04-01

    Graphical abstract: - Highlights: • The synthesis of YbF{sub 3} and NaYbF{sub 4} crystals was successfully fulfilled by hydrothermal method. • The phase and morphology of products were adjusted by changing the hydrothermal conditions. • Relatively enhanced ultraviolet upconversion emissions were observed in YbF{sub 3} nanocrystals. • The crystalline phase impact on the upconversion luminescence was systematically studied. - Abstract: The synthesis of YbF{sub 3} and NaYbF{sub 4} crystals was successfully fulfilled by a facial hydrothermal method. The phase and morphology of the products were adjusted by changing the surfactant additive and fluorine source and tuning the pH value of the initial solution. The products with various morphologies range from octahedral nanoparticles, corn-like nanobundles, nanospheres, microrods, and hollow microprisms were prepared at different conditions. The growth mechanism of these products has been systematically studied. Impressively, relatively enhanced high order ultraviolet (UV) upconversion (UC) luminescence was observed in Tm{sup 3+} (Er{sup 3+}) ions doped YbF{sub 3} nanocrystals (NCs) compared with NaYbF{sub 4} microcrystals under the excitation of 980 nm infrared laser. The investigation results reveal that the crystal symmetry of matrix has significant effect on the spectra and lifetimes of the doping lanthanide ions. The simply synthesized water soluble YbF{sub 3} NCs with efficient UV UC luminescence may find potential application in biochemistry.

  14. Direct Comparison of Yb.sup.3+./sup.:CaF.sub.2./sub. and heavily doped Yb.sup.3+./sup.:YLF as laser media at room temperature

    Czech Academy of Sciences Publication Activity Database

    Pirri, A.; Alderighi, D.; Toci, G.; Vannini, M.; Nikl, Martin; Sato, H.

    2009-01-01

    Roč. 17, č. 20 (2009), s. 18312-18319 ISSN 1094-4087 Grant - others:AV ČR(CZ) M100100910 Institutional research plan: CEZ:AV0Z10100521 Keywords : Yb 3+ :YLF * Yb 3+ :CaF 2 * solid state laser * diode pumped Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.278, year: 2009

  15. Facile synthesis of NaYF4:Yb, Ln/NaYF4:Yb core/shell upconversion nanoparticles via successive ion layer adsorption and one-pot reaction technique

    NARCIS (Netherlands)

    Zeng, Q.; Xue, B.; Zhang, Y.; Wang, D.; Liu, X.; Tu, L.; Zhao, H.; Kong, X.; Zhang, H.

    2013-01-01

    The facile one-pot synthesis of NaYF4:Yb, Ln/NaYF4:Yb core/shell (CS) upconversion nanoparticles (UCNPs) was firstly developed through the successive ion layer adsorption and reaction (SILAR) technique, which represents an attractive alternative to conventional synthesis utilizing the chloride of Ln

  16. The contribution of valence unstable ytterbium states into kinetic properties of YbNi{sub 2-x}Ge{sub 2+x} and YbCu{sub 2-x}Si{sub 2+x}

    Energy Technology Data Exchange (ETDEWEB)

    Kuzhel, B.C. [Department of Physics, Ivan Franko National University of Lviv, 50 Dragomanow Str., 79005, Lviv (Ukraine)]. E-mail: kuzhelb@org.lviv.net; Shcherba, I.D. [Department of Physics, Ivan Franko National University of Lviv, 50 Dragomanow Str., 79005, Lviv (Ukraine); Institute of Techniques, Academy of Pedagogy, Podchorozych 2, 30-084, Krakow (Poland); Kravchenko, I.I. [Department of Physics, University of Florida, P.O. Box 118440, Gainesville, FL 32611 (United States)]. E-mail: kravch@phys.ufl.edu

    2006-11-30

    The intermetalic YbNi{sub 2-x}Ge{sub 2+x} (-0.25>=x>=0.25) and YbCu{sub 2-x}Si{sub 2+x} (-0.20>=x>=0.20) alloy systems (CeGa{sub 2}Al{sub 2} -type crystal structure) were studied by measuring X-ray absorption and diffraction at room temperatures as well as electrical resistivity and thermopower in the 4.2-300K temperature range. The temperature dependence of the contribution of valence unstable Yb ions to the total electrical resistance has been analyzed. The qualitative estimation of this contribution has been performed by utilizing the following equation:{delta}{rho}{sub Yb}(T)={rho}{sub exp}(T)-{rho}{sub YbCu{sub 2}Ge{sub 2}}(T)-{delta}{rho}{sub 4.2K},where {delta}{rho}{sub YbCu{sub 2}Ge{sub 2}}(T) is the temperature dependence of YbCu{sub 2}Ge{sub 2} electrical resistance, {delta}{rho}{sub 4.2}={rho}{sub 4.2}(exp)-{rho}{sub 4.2}(YbCu{sub 2}Ge{sub 2})

  17. The contribution of valence unstable ytterbium states into kinetic properties of YbNi2-xGe2+x and YbCu2-xSi2+x

    International Nuclear Information System (INIS)

    Kuzhel, B.C.; Shcherba, I.D.; Kravchenko, I.I.

    2006-01-01

    The intermetalic YbNi 2-x Ge 2+x (-0.25>=x>=0.25) and YbCu 2-x Si 2+x (-0.20>=x>=0.20) alloy systems (CeGa 2 Al 2 -type crystal structure) were studied by measuring X-ray absorption and diffraction at room temperatures as well as electrical resistivity and thermopower in the 4.2-300K temperature range. The temperature dependence of the contribution of valence unstable Yb ions to the total electrical resistance has been analyzed. The qualitative estimation of this contribution has been performed by utilizing the following equation:Δρ Yb (T)=ρ exp (T)-ρ YbCu 2 Ge 2 (T)-Δρ 4.2K ,where Δρ YbCu 2 Ge 2 (T) is the temperature dependence of YbCu 2 Ge 2 electrical resistance, Δρ 4.2 =ρ 4.2 (exp)-ρ 4.2 (YbCu 2 Ge 2 )

  18. Wir zeigen andere Bilder von Frauen ...

    Directory of Open Access Journals (Sweden)

    Bettina Rulofs

    2010-03-01

    Full Text Available Der vorliegende Beitrag beleuchtet die Bedeutung der Geschlechterordnung im Prozess der sportmedialen Kommunikation. Im Kern geht es um die Frage, inwiefern im Prozess der medialen Vermittlung von Sport traditionelle Geschlechterstereotype aufrechterhalten werden oder Möglichkeiten der Irritation solcher Stereotype bestehen. Dazu werden verschiedene Ebenen des massenmedialen Kommunikationsprozesses in den Blick genommen: die Medienprodukte, die Öffentlichkeitsarbeit und Selbst-Präsentation der Sportler/innen, die Medienrezeption und die Herstellungsprozesse von Medien in den Sportredaktionen. This article illustrates the relevance of gender in processes of sports media communication. The question in focus is in what way traditional gender stereotypes are perpetuated in the process of media communication in sport and how such stereotypes can be irritated. Therefore different levels of mass media communication are considered: the media products, the public relations of athletes and the presentation of themselves as athletes, the media-reception and the production processes in sport departments of media institutions.

  19. The Molecular Genetics of von Willebrand Disease

    Directory of Open Access Journals (Sweden)

    Ergül Berber

    2012-12-01

    Full Text Available Quantitative and/or qualitative deficiency of von Willebrand factor (vWF is associated with the most common inherited bleeding disease von Willebrand disease (vWD. vWD is a complex disease with clinical and genetic heterogeneity. Incomplete penetrance and variable expression due to genetic and environmental factors contribute to its complexity. vWD also has a complex molecular pathogenesis. Some vWF gene mutations are associated with the affected vWF biosynthesis and multimerization, whereas others are associated with increased clearance and functional impairment. Moreover, in addition to a particular mutation, type O blood may result in the more severe phenotype. The present review aimed to provide a summary of the current literature on the molecular genetics of vWD.

  20. The molecular genetics of von Willebrand disease.

    Science.gov (United States)

    Berber, Ergül

    2012-12-01

    Quantitative and/or qualitative deficiency of von Willebrand factor (vWF) is associated with the most common inherited bleeding disease von Willebrand disease (vWD). vWD is a complex disease with clinical and genetic heterogeneity. Incomplete penetrance and variable expression due to genetic and environmental factors contribute to its complexity. vWD also has a complex molecular pathogenesis. Some vWF gene mutations are associated with the affected vWF biosynthesis and multimerization, whereas others are associated with increased clearance and functional impairment. Moreover, in addition to a particular mutation, type O blood may result in the more severe phenotype. The present review aimed to provide a summary of the current literature on the molecular genetics of vWD. None declared.

  1. von Neumann's hypothesis concerning coherent states

    International Nuclear Information System (INIS)

    Zak, J

    2003-01-01

    An orthonormal basis of modified coherent states is constructed. Each member of the basis is an infinite sum of coherent states on a von Neumann lattice. A single state is assigned to each unit cell of area h (Planck constant) in the phase plane. The uncertainties of the coordinate x and the square of the momentum p 2 for these states are shown to be similar to those for the usual coherent states. Expansions in the newly established set are discussed and it is shown that any function in the kq-representation can be written as a sum of two fixed kq-functions. Approximate commuting operators for x and p 2 are defined on a lattice in phase plane according to von Neumann's prescription. (leeter to the editor)

  2. Theodor von Grotthuss’ Contribution to Electrochemistry

    International Nuclear Information System (INIS)

    Pauliukaite, Rasa; Juodkazytė, Jurga; Ramanauskas, Rimantas

    2017-01-01

    Freiherr Christian Johann Dietrich Theodor von Grotthuss (1785-1822) lived and worked in Lithuania. Inspired by Volta's pile he proposed the first theory of water electrolysis, which was published in 1805 in Rome. Michael Faraday acknowledged T. Grotthuss for this theory in his further investigations of electrolysis processes. Having studied in Germany and France Grotthuss brought science to province by establishing his laboratory in Gedučiai village in his mother's real estate. Lithuanian scientists are proud that life of Theodor von Grotthuss was related to this country. Many events to remember this prominent scientist are organised in Vilnius and other places. His works and example provided a good basis for further development of electrochemical science in Lithuania. Grotthuss insights into the mechanism of proton transport still are of great relevance to such areas of modern science as membrane biochemistry, energy conversion and storage.

  3. Inattentional blindness and the von Restorff effect.

    Science.gov (United States)

    Schmidt, Stephen R; Schmidt, Constance R

    2015-02-01

    Sometimes we fail to notice distinctive or unusual items (inattentional blindness), while other times we remember distinctive items more than expected items (the von Restorff effect). A three-factor framework is presented and tested in two experiments in an attempt to reconcile these seemingly contradictory phenomena. Memory for different types of unexpected stimuli was tested after an easy or difficult Stroop color-naming task. Highly arousing taboo words were well remembered even when the difficult Stroop task limited attentional resources. However, a conceptual isolation effect was only observed when the nature of the category change was highlighted by the Stroop task, the Stroop task was easy, and/or the isolated targets enjoyed a retrieval advantage relative to comparison targets. As proposed in the three-factor framework, the arousing qualities of the stimuli, the attentional demands of the primary task, and the relevance of isolated features at encoding and retrieval combine to produce inattentional blindness and the von Restorff effect.

  4. Verbesserung der Symmetrie von Hirnaufnahmen entlang der Sagittalebene

    Science.gov (United States)

    Ens, Konstantin; Wenzel, Fabian; Fischer, Bernd

    Die lokale Symmetrie von Hirnscans entlang der Sagittalebene zu ermitteln und zu modizifieren, ist für eine Reihe neurologischer Anwendungen interessant. Beispielsweise kann der voxelweise Vergleich von rechter und linker Hirnhälfte nur dann Aufschluss über die Lokalisierung von Läsionen geben, wenn durch Transformation ein Hirnscan eine möglichst hohe Symmetrie aufweist. Ein weiteres Anwendungsgebiet ist die Visualisierung von medialen Hirnschnitten, für die die Trennfläche beider Hirnhälfte möglichst eben sein sollte. Diese Arbeit stellt die Entwicklung eines Verfahrens vor, mit dessen Hilfe die Symmetrie von Hirnaufnahmen entlang der Sagittalebene verbessert werden kann. Dies geschieht unter Verwendung von aktiven Konturen, die mit Hilfe einer neuartigen Kostenfunktion gesteuert werden. Experimente am Ende der Arbeit mit strukturellen Kernspinaufnahmen demonstrieren die Leistungsfähigkeit des Verfahrens.

  5. Rohlin flows on Von Neumann algebras

    CERN Document Server

    Masuda, Toshihiko

    2016-01-01

    The authors will classify Rohlin flows on von Neumann algebras up to strong cocycle conjugacy. This result provides alternative approaches to some preceding results such as Kawahigashi's classification of flows on the injective type II_1 factor, the classification of injective type III factors due to Connes, Krieger and Haagerup and the non-fullness of type III_0 factors. Several concrete examples are also studied.

  6. Marktorientierte Vertriebs-Reorganisation von Energieversorgungsunternehmen

    OpenAIRE

    Beutin, Nikolas; Scholl, Michael; Fürst, Andreas

    2003-01-01

    Seit der Liberalisierung des Energiemarktes im Jahre 1998 sehen sich Energieversorgungsunternehmen (EVUs) einer veränderten Markt- und Wettbewerbssituation gegenüber. Neben Risiken, wie dem Eintritt von Wettbewerbern in das vormals geschützte Gebiet, eröffnete sich ihnen hierdurch aber auch die Chance, außerhalb des eigenen Netzbereiches neue Kunden zu gewinnen. Um sowohl dem Margenverfall als auch der direkten Vergleichbarkeit mit ...

  7. La Medea de Lars von Trier

    Directory of Open Access Journals (Sweden)

    Iratxe Fresneda Delgado

    2013-04-01

    Full Text Available El presente artículo analiza el modo en el que Lars von Trier recrea para el cine el estereotipo de Medea. Mediante el análisis fílmico de la película y apoyándose en los estudios culturales, el texto se interroga acerca de la importancia y el poder potencial del cine a la hora recuperar el antiguo mito y demostrar su vigencia. El análisis amplía horizontes para la compresión de los mecanismos que articulan el entramado de significados de la película, donde Von Trier aporta una nueva visión del arquetipo de Medea uniéndola, a la tradición pictórica del Romanticismo. Una influencia que habita en las posteriores obras del director danés, donde el paisaje, la naturaleza, se erige en elemento catalizador de las pulsiones humanas, en su cómplice y testigo.This paper explores the way that Lars von Trier’s film recreates the stereotype of Medea. Using film analysis and based on cultural studies the article asks about the importance and potential power of cinema to recover the ancient myth and show their effects. The analysis expands horizons for the understanding of the mechanisms that link the network of meanings of the film, where the author offers a new vision of Medea's archetype attaching it to the pictorial tradition tied to the Romanticism. An influence that can be seen in the later works of Lars von Trier, where the landscape, the nature, stands as a catalyst of human drives, as his accomplice and witness.

  8. Visuelle Analyse von E-mail-Verkehr

    OpenAIRE

    Mansmann, Florian

    2003-01-01

    Diese Arbeit beschreibt Methoden zur visuellen geographischen Analyse von E-mail Verkehr.Aus dem Header einer E-mail können Hostadressen und IP-Adressen herausgefiltert werden. Anhand einer Datenbank werden diesen Host- und IP-Adressen geographische Koordinaten zugeordnet.Durch eine Visualisierung werden in übersichtlicher Art und Weise mehrere tausend E-mail Routen dargestellt. Zusätzlich dazu wurden interktive Manipulationsmöglichkeiten vorgestellt, welche eine visuelle Exploration der Date...

  9. Zur Kenntnis von Gnetum neglectum Bl

    NARCIS (Netherlands)

    Markgraf, F.

    1960-01-01

    Gnetum neglectum war nicht nur, wie der Name andeutet, bis zu Blumes Zeit übersehen worden, sondern es wurde von Späteren wiederum verkannt, wie ich in Bull. J. B. Buitenzorg 3. Ser. 10 (1930) 474 näher ausgeführt habe. Die echte Art taucht verhältnismässig selten in den Herbarien auf. Sie ist eine

  10. Von Medien, Übertragungen und Automaten

    Directory of Open Access Journals (Sweden)

    Alessandro Barberi

    2013-12-01

    Full Text Available Im Zuge der Debatten zum Medialen Habitus wurde vielfach betont, dass die >Theorie der Praxispraxeologischen Medientheorie< des Medialen Habitus avant la lettre gesprochen werden kann. Dieser Artikel untersucht – ausgehend von den Debatten zur "Medienkompetenz" – wie Bourdieu Sprache, Sprechen und Diskurs, sowie Akteure, Felder und Habitus als Medien begreift und betont dabei die Nützlichkeit der Bourdieuschen Bildungssoziologie im Rahmen einer sozialwissenschaftlichen Grundlegung der Medienpädagogik.

  11. Infrared to near-infrared and visible upconversion mechanisms in LiYF 4: Yb3+, Ho3+

    NARCIS (Netherlands)

    Martín-Rodríguez, R.; Meijerink, A.|info:eu-repo/dai/nl/075044986

    2014-01-01

    Upconversion materials have regained interest in recent years due to their potential to enhance the efficiency of solar cells. The research has focused on lanthanide based upconverters, especially Er3+- and Yb 3+-doped materials. In this paper we report Ho3+ and Yb3+ upconversion after excitation

  12. Twist and YB-1 gene expression in cervical cancer and precancerous tissue and their correlation with cell invasion

    Directory of Open Access Journals (Sweden)

    Qin Tian

    2017-04-01

    Full Text Available Objective: To study the correlation of Twist and YB-1 gene expression in cervical cancer and precancerous tissue with cell invasion. Methods: Cervical cancer tissue, precancerous tissue and normal cervical tissue surgically removed in our hospital between May 2013 and April 2015 were collected; immunohistochemical staining kits were used to detect the positive protein expression rate of Twist and YB-1 gene; fluorescence quantitative PCR kits were used to detect Twist, YB-1 and invasion gene mRNA expression. Results: Twist and YB-1 mRNA expression and positive protein expression rate as well as USP22, Rab11, Rac1 and ANXA5 mRNA expression in cervical cancer tissue and precancerous tissue were significantly higher than those in normal cervical tissue, Twist and YB-1 mRNA expression and positive protein expression rate as well as USP22, Rab11, Rac1 and ANXA5 mRNA expression in cervical cancer tissue were significantly higher than those in precancerous tissue; USP22, Rab11, Rac1 and ANXA5 mRNA expression in cervical cancer tissue and precancerous tissue with positive Twist and YB-1 expression were significantly higher than those in cervical cancer tissue and precancerous tissue with negative Twist and YB-1 expression. Conclusion: Highly expressed Twist and YB-1 in cervical cancer and precancerous tissue can promote cell invasion.

  13. Spectroscopic properties of Er3+ and Yb3+ co-doped glass ceramics containing SrF2 nanocrystals

    International Nuclear Information System (INIS)

    Qiao Xvsheng; Fan Xianping; Wang Minquan; Zhang Xianghua

    2009-01-01

    The spectroscopic properties of Er 3+ /Yb 3+ co-doped 50SiO 2 -10Al 2 O 3 -20ZnF 2 -20SrF 2 glass and glass ceramic containing SrF 2 nanocrystals were investigated. The formation of SrF 2 nanocrystals in the glass ceramic was confirmed by XRD. The oscillator strengths for several transitions of the Er 3+ ions in the glass ceramic have been obtained and the Judd-Ofelt parameters were then determined. The XRD result and Judd-Ofelt parameters suggested that Er 3+ and Yb 3+ ions had efficiently enriched in the SrF 2 nanocrystals in the glass ceramic. The lifetime of excited states has been used to reveal the surroundings of luminescent Er 3+ and Yb 3+ and energy transfer (ET) mechanism between Er 3+ and Yb 3+ . Much stronger upconversion luminescence and longer lifetime of the Er 3+ /Yb 3+ co-doped glass ceramic were observed in comparison with the Er 3+ /Yb 3+ co-doped glass, which could be ascribed to more efficient ET from Yb 3+ to Er 3+ due to the enrichment of Yb 3+ and Er 3+ and the shortening of the distance between lanthanide ions in the precipitated SrF 2 nanocrystals.

  14. Optical properties of silica-coated Y2O3:Er,Yb nanoparticles in the presence of polyvinylpyrrolidone

    International Nuclear Information System (INIS)

    Fujii, Kunio; Kitamoto, Yoshitaka; Hara, Masahiko; Odawara, Osamu; Wada, Hiroyuki

    2014-01-01

    The optical properties of polyvinylpyrrolidone (PVP)-adsorbed and silica-coated Y 2 O 3 :Er,Yb nanoparticles produced by using PVP were studied for potential bio-applications of upconversion nanoparticles. We utilized PVP to better disperse Y 2 O 3 :Er,Yb nanoparticles in solution and to prepare silica-coated Y 2 O 3 :Er,Yb nanoparticles. The fluorescent intensity of PVP-adsorbed Y 2 O 3 :Er,Yb nanoparticles was 1.25 times higher than non-adsorbed Y 2 O 3 :Er,Yb nanoparticles, which was probably due to surface defects in Y 2 O 3 :Er,Yb nanoparticles being covered by the PVP. However, the fluorescent intensity of silica-coated Y 2 O 3 :Er,Yb nanoparticles decreased as silica layer thickness increased. This could be ascribed to the higher vibrational energy of PVP than that of the silica structure. Therefore, the optimum silica layer thickness is important in bio-applications to avoid deterioration of the optical properties of Y 2 O 3 :Er,Yb nanoparticles. - Highlights: • We prepared the silica-coated upconversion nanoparticles by using PVP. • We showed that PVP played an important role in coating nanoparticles. • PL intensity of silica-coated nanoparticles decreased as silica layer thickness increased

  15. Polarographic reduction of Yb/sup +3/ benzoate and salicylate complexes in aqueous-nonaqueous mixtures at D. M. E

    Energy Technology Data Exchange (ETDEWEB)

    Zutshi, K; Gupta, K C [Rajasthan Univ., Jaipur (India). Dept. of Chemistry

    1977-01-01

    The reduction of Yb/sup +3/ and Yb/sup +3/-benzoate and salicylate complexes was studied polarographically at constant ionic strength at 25 +- 0.02/sup 0/C in aqueous-nonaqueous mixtures. The reduction was found to be diffusion-controlled, but the electrode process was irreversible in all cases. The kinetic parameters were determined by Koutecky's method.

  16. Portrait of Dr. Von Braun with Walt Disney, 1954.

    Science.gov (United States)

    1954-01-01

    Marshall Center Director Dr. Wernher Von Braun is pictured with Walt Disney during a visit to the Marshall Space Flight Center in 1954. In the 1950s, Dr. Von Braun while working in California on the Saturn project, also worked with Disney studios as a technical director in making three films about Space Exploration for television. Disney's tour of Marshall in 1965 was Von Braun's hope for a renewed public interest in the future of the Space Program at NASA.

  17. Gespiegelte Planeten – Die Anordnung der Pyramiden von Gizeh

    OpenAIRE

    Jelitto, Hans

    2000-01-01

    Antike Bauwerke wurden wiederholt auf astronomische Zusammenhänge hin untersucht, so z. B. ihre Ausrichtung in Bezug auf die Bewegung von Sonne oder Sternen. Vor diesem Hintergrund wurden für die Pyramiden von Gizeh drei ungewöhnliche Gleichungen entdeckt, die die Pyramidengrößen mit einer Genauigkeit von ca. 0,1 % festlegen. Gleichzeitig legen diese drei Gleichungen nahe, die drei Pyramiden in der Reihenfolge Mykerinos-, Chefren- und Cheopspyramide den inneren drei Planeten unseres Sonnensys...

  18. Saage tuttavaks : Elisabeth ja Karl von Hoerschelmann / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2004-01-01

    Kuraator M. Levin kuni 10. X 2004 Adamson-Ericu muuseumis avatud näitusest "Tuntud ja tundmatud Elisabeth von Rosendorff-Hoerschelmann ja Karl von Hoerschelmann". Enamik töid on kunstnike laste Konstantin Hoerschelmanni ja Anna Röder-Hoerschelmanni omand. Elisabeth Rosendorff (1898-1984) sündis Virumaal Maidlas eesti perekonnas, Karl von Hoerschelmann (1899-1951) Sevastoopolis saksa perekonnas

  19. Arbeitszeiten von Professorinnen und Professoren in Deutschland 2016

    OpenAIRE

    Weihs, Claus; Hernández Rodríguez, Tanja; Doeckel, Maximilian; Marty, Christoph; Wormer, Holger

    2018-01-01

    In dieser Studie werden belastbare Prognoseintervalle der wöchentlichen Gesamtarbeitszeit von Universitätsprofessorinnen und -professoren aus Daten einer Umfrage aus dem Jahre 2016 und a-priori Informationen aus früheren Studien bestimmt. Neben der Gesamtarbeitszeit werden auch Teilarbeitszeiten zum Beispiel für Lehre und Forschung ermittelt. Die Ergebnisse von frequentistischer und Bayesianischer Analyse werden verglichen. Aus den gültigen Fragebögen von aktiven Vollzeit arbeitenden Universi...

  20. Cooperative up-conversion processes in SrAl{sub 4}O{sub 7}:Yb and SrAl{sub 4}O{sub 7}:Yb,Tb and their dependence on charge compensation by Na

    Energy Technology Data Exchange (ETDEWEB)

    Puchalska, M., E-mail: malgorzata.puchalska@chem.uni.wroc.pl [Faculty of Chemistry, University of Wroclaw, 14, F. Joliot-Curie Street, 50-383 Wroclaw (Poland); Zych, E. [Faculty of Chemistry, University of Wroclaw, 14, F. Joliot-Curie Street, 50-383 Wroclaw (Poland); Watras, A. [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, 2 Okólna Street, 50-422 Wrocław (Poland)

    2017-03-15

    A detailed analysis of the luminescence behaviour of Yb{sup 3+}-doped and Yb{sup 3+}-Tb{sup 3+} co-doped strontium aluminates powders: Sr{sub 1-x}Yb{sub x}Al{sub 4}O{sub 7} (x=0.002–0.07) and Sr{sub 1-x-y}Yb{sub x}Tb{sub y}Al{sub 4}O{sub 7} (x=0.03; y=0.002–0.02) were performed. The studies of singly doped samples show that direct excitation of Yb{sup 3+} by means of {sup 2}F{sub 7/2}-{sup 2}F{sub 5/2} absorption at 900–980 nm leads to Stokes Yb{sup 3+} emission in the range of 970–1130 nm as well as bluish-green Yb{sup 3+} cooperative luminescence (CL) whose energy doubles that of the NIR one. The effect of activator concentration and charge compensation through Na{sup +} co-doping on both Yb{sup 3+} emissions were also studied. It was found that Na{sup +} addition enhanced Stokes Yb{sup 3+} photoluminescence brightness, while the cooperative emission intensity appeared to be lower. In doubly Yb{sup 3+}-Tb{sup 3+} doped materials excitation at 980 nm led to cooperative sensitization of the Tb{sup 3+} {sup 5}D{sub 4} level giving rise to its green {sup 5}D{sub 4}→{sup 7}F{sub J} (J={sup 7}F{sub 6}-{sup 7}F{sub 3}) up-conversion luminescence with the dominant component around 542 nm. The cooperative energy transfer (CET) mechanism was proposed basing on the results obtained from emission and absorption spectra, decay kinetics as well as the dependence of UC luminescence intensity on NIR excitation power.

  1. Continuous-wave diode-pumped Yb 3+:LYSO tunable laser

    Science.gov (United States)

    Du, Juan; Liang, Xiaoyan; Xu, Yi; Li, Ruxin; Yan, Chengfeng; Zhao, Guangjun; Su, Liangbi; Xu, Jun; Xu, Zhizhan

    2007-01-01

    A new alloyed crystal, Yb:LYSO, has been grown by the Czochralski method in our institute for the first time, and its effective diode-pumped cw tunable laser action was demonstrated. The alloyed crystal retains excellent laser properties of LSO with reduced growth cost, as well as the favorable growth properties of YSO. With a 5-at.% Yb:LYSO sample, we achieved 2.84 W output power at 1085 nm and a slope efficiency of 63.5%. And its laser wavelength could be tuned over a range broader than 80nm, from 1030nm to 1111 nm. This is the broadest tunable range achieved for Yb:LYSO laser, as far as we know.

  2. Investigation of luminescence properties in SiO2: Tb, Yb upconversion inverse opal

    International Nuclear Information System (INIS)

    Yang Zhengwen; Yan Dong; Song Zhiguo; Zhou Dacheng; Yu Xue; Yang Yong; Yin Zhaoyi; Yan Lei; Wang Rongfei; Wu Hangjun; Qiu Jianbei

    2012-01-01

    The SiO 2 : Tb, Yb inverse opals with photonic band gap at 465 or 543 nm were prepared, and an effect of photonic band gap on upconversion spontaneous emission from Tb 3+ was investigated. The results show that the photonic band gap has a significant influence on the upconversion emission of the SiO 2 : Tb, Yb inverse opals. The upconversion luminescence of the Tb 3+ ions is suppressed in the inverse opal compared with the luminescence of that of the reference sample. - Highlights: ► Upconversion emission from Tb 3+ was observed in the SiO 2 : Tb, Yb inverse opal. ► UC emission of Tb 3+ was modulated by controlling the structure of inverse opal. ► UC emission of Tb 3+ was depressed in the inverse opal.

  3. Yb:Y2O3 transparent ceramics processed with hot isostatic pressing

    Science.gov (United States)

    Wang, Jun; Ma, Jie; Zhang, Jian; Liu, Peng; Luo, Dewei; Yin, Danlei; Tang, Dingyuan; Kong, Ling Bing

    2017-09-01

    Highly transparent 5 at.% Yb:Y2O3 ceramics were fabricated by using a combination method of vacuum sintering and hot isostatic pressing (HIP). Co-precipitated Yb:Y2O3 powders, with 1 at.% ZrO2 as the sintering aid, were used as the starting material. The Yb:Y2O3 ceramics, vacuum sintered at 1700 °C for 2 h and HIPed at 1775 °C for 4 h, exhibited small grain size of 1.9 μm and highly dense microstructure. In-line optical transmittance of the ceramics reached 83.4% and 78.9% at 2000 and 600 nm, respectively. As the ceramic slab was pumped by a fiber-coupled laser diode at about 940 nm, a maximum output power of 0.77 W at 1076 nm was achieved, with a corresponding slope efficiency of 10.6%.

  4. Cr and Yb markers determination in animal feces by energy dispersive X-ray fluorescence

    International Nuclear Information System (INIS)

    Almeida, Eduardo de; Senicato, Luis A; Nascimento Filho, Virgilio F.; Gomide, Catarina A.

    2007-01-01

    Chromium and Ytterbium elements are utilized in animal nutritional studies as markers. This paper describes an analytical method for Cr and Yb determination in solid buffalo feces sample using standard addition method and energy dispersive X-ray spectrometry (EDXRF) technique. One gram dried sample was pressed manually in an XRF sample cup with Mylar film (6.3 μm thickness) in the bottom. The experimental conditions were: Mo target X-ray tube with Zr filter, operated at 25 kV/10 mA, and 500 s of acquisition time. The limits of detection for Cr and Yb were 16.6 and 11.4 mg/kg, respectively. This methodology has showed appropriated for simultaneous Cr and Yb determination as marker in animal feces. (author)

  5. Cr and Yb markers determination in animal feces by energy dispersive X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Eduardo de; Senicato, Luis A; Nascimento Filho, Virgilio F. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Instrumentacao Nuclear (LIN)]. E-mail: edualm@usp.br; Gomide, Catarina A. [Universidade de Sao Paulo (USP), Pirassununga, SP (Brazil). Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Dept. de Zootecnia]. E-mail: cbgomide@usp.br

    2007-07-01

    Chromium and Ytterbium elements are utilized in animal nutritional studies as markers. This paper describes an analytical method for Cr and Yb determination in solid buffalo feces sample using standard addition method and energy dispersive X-ray spectrometry (EDXRF) technique. One gram dried sample was pressed manually in an XRF sample cup with Mylar film (6.3 {mu}m thickness) in the bottom. The experimental conditions were: Mo target X-ray tube with Zr filter, operated at 25 kV/10 mA, and 500 s of acquisition time. The limits of detection for Cr and Yb were 16.6 and 11.4 mg/kg, respectively. This methodology has showed appropriated for simultaneous Cr and Yb determination as marker in animal feces. (author)

  6. Fluorescence properties of Yb3+-Er3+ co-doped phosphate glasses containing silver nanoparticles

    Science.gov (United States)

    Martínez Gámez, Ma A.; Vallejo H, Miguel A.; Kiryanov, A. V.; Licea-Jiménez, L.; Lucio M, J. L.; Pérez-García, S. A.

    2018-04-01

    Er3+-Yb3+ co-doped phosphate glasses containing silver nitrate (SN), were fabricated. Transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy (XPS) analyses were used to evidence the nucleation and presence of silver nanoparticles (SNP). The basic parameters of the glasses were inspected by means of absorption and fluorescence spectra, and fluorescence lifetimes under excitation at 916 nm (in-band of Yb3+), and at 406 nm (in-band of surface plasmon resonance given by the presence of SNP). The spectra as well as estimates for the basic parameters defining the lasing/amplifying potential of the glasses were studied as a function of SN concentration. The experimental results indicate that by increasing the SN content an enhancement of Er3+/Yb3+ fluorescence takes place.

  7. Untersuchungen zur Farbreaktion von Amilorid, Chlorhexidin und Proguanil mit Hypobromit

    OpenAIRE

    Huth, Silke

    2004-01-01

    Bei der Reaktion von Amiloridhydrochlorid (1· HCl) mit Brom in alkalischer Lösung wird ein gelbbraunes Dehydrierungsprodukt erhalten, daß als 3-(3-Amino-1,2,4-oxadiazol-5-yl)-5-chlor-2,6-pyrazindiamin (6) identifiziert werden konnte. Durch Vergleich von Massen- und NMR-Spektren der Verbindung 6 mit Spektren von 1· HCl und Referenzsubstanzen I-III konnte auf die verbindung 6 geschlossen werden. Die Struktur wurde durch eine Röntgenstrukturanalyse abgesichert. Erhitzen von Amiloridhydrochlorid ...

  8. Chancen und Gefahren von Global-Marketing-Konzepten

    OpenAIRE

    Berndt, Ulrike

    1990-01-01

    Chancen und Gefahren von Global-Marketing-Konzepten. - Augsburg : Förderges. Marketing, 1990. - 57, XII S. - Zugl: Augsburg, Univ., Diplomarb. - (Arbeitspapiere zur Schriftenreihe Schwerpunkt Marketing ; 29)

  9. A bicategorical approach to Morita equivalence for von Neumann algebras

    International Nuclear Information System (INIS)

    Brouwer, R. M.

    2003-01-01

    We relate Morita equivalence for von Neumann algebras to the ''Connes fusion'' tensor product between correspondences. In the purely algebraic setting, it is well known that rings are Morita equivalent if they are equivalent objects in a bicategory whose 1-cells are bimodules. We present a similar result for von Neumann algebras. We show that von Neumann algebras form a bicategory, having Connes's correspondences as 1-morphisms, and (bounded) intertwiners as 2-morphisms. Further, we prove that two von Neumann algebras are Morita equivalent iff they are equivalent objects in the bicategory. The proofs make extensive use of the Tomita-Takesaki modular theory

  10. Optical properties and thermal stability of LaYbO3 ternary oxide for high-k dielectric application

    Science.gov (United States)

    Su, Wei-tao; Yang, Li; Li, Bin

    2011-01-01

    A new ternary rare oxide dielectric LaYbO3 film had been prepared on silicon wafers and quartz substrates by reactive sputtering method using a La-Yb metal target. A range of analysis techniques was performed to determine the optical band gap, thermal stability, and electrical property of the deposited samples. It was found the band gap of LaYbO3 film was about 5.8 eV. And the crystallization temperature for rapid thermal annealing (20 s) was between 900 and 950 °C. X-ray photoelectron spectroscopy results indicate the formation of the SiO2 and silicate in the interface between silicon wafer and LaYbO3 film. The dielectric constant is about 23 from the calculation of capacitance-voltage curve, which is comparable higher than previously reported La2O3 or Yb2O3 film.

  11. Study of subcellular distribution of /sup 169/Yb and /sup 111/In in tumor and liver

    Energy Technology Data Exchange (ETDEWEB)

    Ando, A; Takeshita, M; Hiraki, T [Kanazawa Univ. (Japan). School of Paramedicine; Ando, Itsuko; Hisada, Kinichi

    1977-03-01

    Rats were implanted with Yoshida sarcoma and hepatoma AH109A; and mice were implanted with Ehrlich tumor. /sup 169/Yb-citrate and /sup 111/In-citrate were injected into the rats intravenously and into the mice intraperitoneally. Ten minutes to 48 hours after the administration of /sup 169/Yb-citrate and /sup 111/In-citrate, the animals were sacrificed and the tumor tissues and liver were excised. Subcellular fractionation of tumor tissues and liver was carried out according to the method of Hogeboom and Schneider. The /sup 169/Yb and /sup 111/In of each fraction were counted by a well type scintillation counter, and the protein of each fraction was measured according to Lowry's method. In Yoshida sarcoma and Ehrlich tumor, most of the radioactivity was localized in the supernatant fraction, and a small amount of radioactivity was accumulated in the mitochondrial fraction (lysosome is contained in this fraction). But, in the liver, most of the radioactivity was concentrated in the mitochondrial fraction, and the radioactivity of this fraction was increased with the passage of time after administration. Twenty-four hours later, about 50% of the total radioactivity was accumulated in this fraction. In the case of hepatoma AH109A, radioactivity of the mitochondrial fraction was increased with time after administration, and about 30% of total radioactivity was concentrated in this fraction 24 hours after administration. From these results it is concluded that the lysosome does not play an important role in the concentration of /sup 169/Yb and /sup 111/In in the tumor, and that the lysosome plays an important role in the concentration of /sup 169/Yb and /sup 111/In in the liver. In the case of hepatoma AH109A it is presumed that the lysosome plays a very important role in the concentration of /sup 169/Yb and /sup 111/In, in the tumor as hepatoma AH109A retains some nature of liver.

  12. Der Einfluß der Ablauforganisation auf die Effizienz von Entscheidungen: Eine empirische Untersuchung am Beispiel von Bilanzanalysen

    OpenAIRE

    Gemünden, Hans Georg

    1987-01-01

    Der vorliegende Beitrag widmet sich einem in der Organisationstheorie stark vernachlässigten Problem: der Ablauforganisation von Entscheidungen. Am Beispiel von Bilanzanalysen wird empirisch geprüft, in welcher Weise eine Gliederung des Prozesses nach Verrichtungen oder Objekten die Qualität der Analyse beeinflußt. Hierzu wird ein validiertes Konzept zur Messung der Qualität von Bilanzanalysen entwickelt. Es wird gezeigt, wie man mittels prozeßbegleitender experimenteller Organisationsforschu...

  13. Beeinflussung der Wirkung von Ernährungsinformation durch Framing: Analyse am Beispiel von Folsäure

    OpenAIRE

    Lensch, Kathrin; Hartmann, Monika; Simons, Johannes

    2011-01-01

    Die Bereitstellung und verbrauchergerechte Aufbereitung von Informationen stellt eine Möglichkeit dar, Konsumenten darin zu unterstützen, Gesundheitsaspekte vermehrt in das Kauf- und Essverhalten zu integrieren. In der Verhaltensökonomik gelten Framing-Effekte als wichtige Bestimmungsfaktoren für die Wahrnehmung von Informationen. Im Rahmen des vorliegenden Beitrags werden Framing-Effekte am Beispiel von Ernährungsinformationen über Folsäure mit Hilfe eines Experiments untersucht. Die Ergebni...

  14. Exploring strategies for the production of ultracold RbYb molecules in conservative traps

    Energy Technology Data Exchange (ETDEWEB)

    Bruni, Cristian

    2015-07-14

    Within the scope of this thesis, the production of ultracold molecules at a temperature of a few μK with various isotopes of rubidium (Rb) and ytterbium (Yb) was examined by means of photoassociation spectroscopy and magnetic Feshbach resonances in combined conservative traps. The long-term goal of this experiment is the production of ultracold RbYb molecules in the rovibronic ground state. It was possible to produce electronically excited {sup 87}Rb {sup 176}Yb molecules in a novel hybrid trap (HT) at a combined temperature of 1.7 μK by means of 1-photon photoassociation close to the Rb D1 line at 795 nm. This HT takes advantage of the different magnetic properties of Rb and Yb and allows for independent trapping and manipulation of the atomic species. It combines an Ioffe-Pritchard type magnetic trap for Rb and a near-resonant optical dipole trap for Yb. The excited molecular {sup 2}Π{sub 1/2} state could be characterized further extending previous works in a combined MOT and vibrational levels reaching binding energies up to E{sub b}=-h x 2.2 THz could be assigned by trap-loss spectroscopy. Almost every detected vibrational state consists of two resonances that could be assigned to the molecular analogue of the hyperfine structure of {sup 87}Rb. An important experimental observation is a decrease in hyperfine splitting with increasing binding energy of a vibrational level. For the deepest found vibrational state the hyperfine splitting amounts only 70 % of the atomic value (817 MHz) which emphasizes a gradual passage from weakly to tightly bound molecules. Furthermore, detailed attempts were undertaken to induce magnetic Feshbach resonances in {sup 85}Rb and different Yb isotopes, especially {sup 171}Yb in a crossed optical dipole trap at 1064 nm at temperatures of 10 μK. For this purpose, a homogeneous magnetic field was applied and scanned in small steps over the range of 495 G ∼ 640 G. Unfortunately, our efforts were without success. Additionally, well

  15. Monolithic all-PM femtosecond Yb-doped fiber laser using photonic bandgap fibers

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Lægsgaard, Jesper; Turchinovich, Dmitry

    2009-01-01

    We present a monolithic Yb fiber laser, dispersion managed by an all-solid photonic bandgap fiber, and pulse compressed in a hollow-core photonic crystal fiber. The laser delivers 9 nJ, 275-fs long pulses at 1035 nm.......We present a monolithic Yb fiber laser, dispersion managed by an all-solid photonic bandgap fiber, and pulse compressed in a hollow-core photonic crystal fiber. The laser delivers 9 nJ, 275-fs long pulses at 1035 nm....

  16. Statistical γ-ray multiplicity distributions in Dy and Yb nuclei

    International Nuclear Information System (INIS)

    Tveter, T.S.; Bergholt, L.; Guttormsen, M.; Rekstad, J.

    1994-03-01

    The statistical γ-ray multiplicity distributions following the reactions 163 Dy( 3 He,αxn) 162-x Dy and 173 Yb( 3 He,αxn) 172-x Yb have been studied. The mean value and standard deviation have been extracted as functions of excitation energy. The method is based on the probability distribution of k-fold events, where an α-particle is observed in coincidence with signals in k γ-ray detectors. Techniques for isolating statistical γ-rays and subtracting random background, cross-talk and neutron contributions are discussed. 22 refs., 10 figs., 3 tabs

  17. Crystal field excitations of YbMn{sub 2}Si{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Mole, R.A. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234 (Australia); School of Physical, Environmental and Mathematical Sciences, The University of New South Wales at the Australian Defence Force Academy, Canberra, ACT 2600 (Australia); Hofmann, M. [School of Physical, Environmental and Mathematical Sciences, The University of New South Wales at the Australian Defence Force Academy, Canberra, ACT 2600 (Australia); Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II), Technische Universität München, 85747 Garching (Germany); Adroja, D.T. [ISIS Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, OX11 OQX (United Kingdom); Moze, O. [Dipartimento di Fisica, Università degli Studi di Modena e Reggio Emilia, Modena (Italy); Campbell, S.J., E-mail: stewart.campbell@adfa.edu.au [School of Physical, Environmental and Mathematical Sciences, The University of New South Wales at the Australian Defence Force Academy, Canberra, ACT 2600 (Australia)

    2013-12-15

    The crystal field excitations of the rare earth intermetallic compound YbMn{sub 2}Si{sub 2} have been measured by inelastic neutron scattering over the temperature range 2.5–50 K. The YbMn{sub 2}Si{sub 2} spectra exhibit three low energy excitations (∼3–7 meV) in the antiferromagnetic AFil region above the magnetic phase transition at T{sub N2} = 30(5) K. The crystal field parameters have been determined for YbMn{sub 2}Si{sub 2} in the antiferromagnetic AFil region. A further two inelastic excitations (∼9 meV, 17 meV) are observed below T{sub N2}=30(5) K, the temperature at which the high temperature antiferromagnetic structure is reported to exhibit doubling of the magnetic cell. Energy level diagrams have been determined for Yb{sup 3+} ions in the different sites above (single site) and below the magnetic transition temperature (two sites). The excitation energies for both sites are shown to be temperature independent with the temperature dependences of the transition intensities for the two sites described well by a simple Boltzmann model. The spectra below T{sub N2} cannot be described fully in terms of molecular field models based on either a single Yb{sup 3+} site or two Yb{sup 3+} sites. This indicates that the magnetic behaviour of YbMn{sub 2}Si{sub 2} is more complicated than previously considered. The inability to account fully for excitations below the magnetic phase transition may be due to an, as yet, unresolved structural transition associated with the magnetic transition. - Highlights: • The inelastic neutron scattering from YbMn{sub 2}Si{sub 2} has been investigated over the temperature range 2.5–50 K. • The crystal field splitting has been monitored through the magnetic transition at 30(5) K. • We have determined the crystal field parameters for the antiferromagnetic AFil region. • The transition intensities are described well by Boltzmann occupancy models. • The spectra below the magnetic transition have been analysed by

  18. Creep properties and precipitate evolution in Al-Li alloys microalloyed with Sc and Yb

    Energy Technology Data Exchange (ETDEWEB)

    Krug, Matthew E. [Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208 (United States); Seidman, David N. [Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208 (United States); Northwestern Center for Atom Probe Tomography, Northwestern University, 2220 Campus Drive, Evanston, IL 60208 (United States); Dunand, David C., E-mail: dunand@northwestern.edu [Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208 (United States)

    2012-07-30

    Highlights: Black-Right-Pointing-Pointer We examine the creep behavior of Al-alloys with Li and rare earth element additions. Black-Right-Pointing-Pointer These alloys exhibit threshold stresses below which no measurable creep occurs. Black-Right-Pointing-Pointer Larger precipitate size and lattice parameter mismatch increase creep resistance. Black-Right-Pointing-Pointer A simple parameter describes the threshold stress behavior in ternary Al-Sc-X alloys. Black-Right-Pointing-Pointer The findings are explained by a recent model of dislocation-precipitate interactions. - Abstract: A dilute Al-Sc alloy (Al-0.12 Sc, at.%, Al-Sc), its counterpart with a Li addition (Al-2.9 Li-0.11 Sc, at.%, Al-Li-Sc), as well as a quaternary alloy (Al-5.53 Li-0.048 Sc-0.009 Yb, at.%, Al-Li-Sc-Yb) were isothermally aged at 325 Degree-Sign C, and in some cases isochronally aged to 450 Degree-Sign C. As the {alpha} Prime -Al{sub 3}(Li,Sc) and Al{sub 3}(Li,Sc,Yb) precipitates, with L1{sub 2} structure, coarsen in the two Li-containing alloys, their Li and Yb concentrations decrease and their Sc concentration increases. A significant interfacial excess of Li also segregates at the {alpha}-Al matrix/{alpha} Prime -Al{sub 3}Sc(Li,Sc,Yb) precipitate interface: 5.99 {+-} 0.05 atoms nm{sup -2} in Al-Li-Sc and 13.2 {+-} 0.4 atoms nm{sup -2} in Al-Li-Sc-Yb after aging isochronally to 450 Degree-Sign C. During compression creep at 300 Degree-Sign C, the aged alloys exhibit threshold stresses between 8 and 22 MPa. A recent threshold stress model based on elastic interactions between dislocations and precipitates predicts correctly that Li additions in the Al-Li-Sc alloy reduce the threshold stress, while Yb in the Al-Li-Sc-Yb alloy increases it. The model is also in agreement with the threshold stresses of all Al-Sc-X alloys published to date.

  19. Low-power, miniature {sup 171}Yb ion clock using an ultra-small vacuum package

    Energy Technology Data Exchange (ETDEWEB)

    Jau, Y.-Y.; Schwindt, P. D. D. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Partner, H. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Center for Quantum Information and Control (CQuIC), Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Prestage, J. D.; Kellogg, J. R.; Yu, N. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    2012-12-17

    We report a demonstration of a very small microwave atomic clock using the 12.6 GHz hyperfine transition of the trapped {sup 171}Yb ions inside a miniature, completely sealed-off 3 cm{sup 3} ion-trap vacuum package. In the ion clock system, all of the components are highly miniaturized with low power consumption except the 369 nm optical pumping laser still under development for miniaturization. The entire clock, including the control electronics, consumes <300 mW. The fractional frequency instability of the miniature Yb{sup +} clock reaches the 10{sup -14} range after a few days of integration.

  20. Yb3+ sensitized Tm3+ upconversion in tellurite lead oxide glass.

    Science.gov (United States)

    Mohanty, Deepak Kumar; Rai, Vineet Kumar; Dwivedi, Y

    2012-04-01

    Triply ionized thulium/thulium--ytterbium doped/codoped TeO2-Pb3O4 (TPO) glasses have been fabricated by classical quenching method. The upconversion emission spectra in the Tm3+/Tm3+-Yb3+ doped/codoped glasses upon excitation with a diode laser lasing at ∼980 nm has been studied. Effect of the addition of the Yb3+ on the upconversion emission intensity in the visible and near infrared regions of the Tm3+ doped in TPO glass has been studied and the processes involved explored. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Properties of melt-grown single crystals of 'YB/sub 68/'

    Energy Technology Data Exchange (ETDEWEB)

    Slack, G A; Oliver, D W; Brower, G D; Young, J D [General Electric Co., Schenectady, N.Y. (USA). Research and Development Center

    1977-01-01

    Single crystals of yttrium boride YB/sub n/ with n = 61 +- 3 were grown from the melt. Precision density and lattice parameter measurements indicate a congruent melting point at n = 61.7 and a stoichiometric composition at n = 68. Measurements of elastic constants, acoustic attenuation, electrical resistivity and optical absorption are presented. High resolution transmission electron microscopy reveals a complex crystal structure similar to that found by using X-rays. A comparison of the properties of YB/sub n/ with those of ..beta..-boron show that there are many similarities.

  2. Philologie im Horizont der Geschichtlichkeit von Sprache und Text: zum Tagungsband von Wulf Oesterreicher und Maria Selig

    Directory of Open Access Journals (Sweden)

    Olaf Müller

    2016-03-01

    Full Text Available Wulf Oesterreicher und Maria Selig, Hrsg., Geschichtlichkeit von Sprache und Text: Philologien – Disziplingenese – Wissenschaftshistoriographie (Paderborn: Wilhelm Fink, 2014, 332 S.

  3. Properties of the divalent-Yb compound YbAu.sub.2./sub.Si.sub.2./sub. under extreme conditions

    Czech Academy of Sciences Publication Activity Database

    Kaštil, Jiří; Míšek, Martin; Kamarád, Jiří; Arnold, Zdeněk; Vlášková, K.; Prchal, J.; Diviš, M.; Doležal, P.; Prokleška, J.; Valenta, J.; Fikáček, J.; Rudajevová, A.; Kriegner, D.

    2017-01-01

    Roč. 505, Jan (2017), s. 41-44 ISSN 0921-4526 R&D Projects: GA ČR GA15-03777S Institutional support: RVO:68378271 Keywords : YbAu 2 Si 2 * valence state * high pressure * GGA method Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.386, year: 2016

  4. Microscopic evidence for significant ionic disorder in the Yb sup 3 sup + -chain in Yb sub 4 (As sub 1 sub - sub x P sub x) sub 3 : sup 3 sup 1 P NMR studies

    CERN Document Server

    Tanida, H; Aoki, H; Ochiai, A

    2003-01-01

    We report unambiguous microscopic evidence from sup 3 sup 1 P NMR under H sub e sub x sub t approx = 7.3 T for significant ionic disorder in the Yb sup 3 sup + chain in Yb sub 4 (As sub 1 sub - sub x P sub x) sub 3 (x=0.05 and 0.40), which have similar characteristic chi(T) and C sub p (T, H sub e sub x sub t) behavior to the antiferromagnetic quantum spin chain (AFQSC) system Yb sub 4 As sub 3. Our conclusion is based on the observations only below the charge-ordering transition at T sub 0 approx = 292 K of clear structures in the spectrum, which can be fitted well by the superpositions of almost equally spaced five Gaussian components. Since perfect ordering of Yb sup 3 sup + in the chain sites would lead to a single-line spectrum also below T sub 0 , the structures should be ascribed to significant ionic disorder in the Yb sup 3 sup + chain and resulting distribution of local configurations of Yb sup 3 sup + in the eight nearest-neighboring Yb sites around sup 3 sup 1 P. Quantitative comparisons with a sim...

  5. Von den Liven von Oesel / August Ludwig Schlözer

    Index Scriptorium Estoniae

    Schlözer, August Ludwig

    2008-01-01

    Avaldatud Eberhard Winkleri initsiatiivil A. L. Schlözeri teose põhjal: Gesammelte Nachrichten von den Ueberresten der Liven, in Livland und Kurland. (1770), mis moodustab osa teosest: Schlözer, August Ludwig. M. Johann Joseph Haigold's Beylagen zum Neuveränderten Russland. Zweiter Theil. Riga und Leipzig, 1770

  6. Aino Lepik von Wiren / Aino Lepik von Wiren ; interv. Kadi Alatalu

    Index Scriptorium Estoniae

    Lepik von Wirén, Aino, 1961-

    2007-01-01

    Heinrich Marga eksiilvalitsuse (20.06.1990-7.10.1992) kohtuminister Aino Lepik von Wiren pagulaslapse elust Rootsis, haridusest ja elukutse valikust, tööst eksiilvalitsuses, tööleasumisest Eestisse 1992. aastal, seadusandlikust tegevusest ning aluse panekust välismaalaste- ja kodakondsuspoliitikale, naiste võimalustest poliitilisse tippu tõusmiseks, kodu- ja väliseestlaste vastandamisest

  7. Ööklubi Club von Überlingen = Club von Überlingen

    Index Scriptorium Estoniae

    2008-01-01

    Ööklubi Club von Überlingen (Madara 22A, Tallinn) sisekujundusest. Sisearhitekt: Taavi Aunre (Boom.ee OÜ). Taavi Aunrest, tema tähtsamad tööd. I-II korruse plaan, 11 värv. vaadet, foto T. Aunrest

  8. Wavelengths, classifications, and ionization energies in the isoelectronic sequences from Yb II and Yb III through Bi XV and Bi XVI

    International Nuclear Information System (INIS)

    Kaufman, V.; Sugar, J.

    1976-01-01

    Spectral observations are reported for transitions to the ground term and first excited term of the one-electron configurations in the 4f/sup 14/5p 6 nl isoelectronic sequence from Yb II through Bi XV. Resonance lines are reported for the isoelectronic sequence Yb III through Bi XVI in which the ground state is 4f/sup 14/5p 6 1 S 0 and the upper levels are the J = 1 levels of the 4f/sup 13/5p 6 nd, 4f/sup 14/5p 5 nd, and 4f/sup 14/5p 5 ns configurations. The wavelengths fall in the range 70--3700 A. The spectra were produced by means of sliding and triggered spark discharges and photographed with 10.7 m normal and grazing incidence spectrographs. The data in the Yb III sequence demonstrate the crossing of binding energies of the 4f and 5p shells at W VII. Rydberg series terms were found in a sufficient number of cases to provide extrapolation curves through Bi XV and Bi XVI. These data enabled us to calculate ionization energies for each of these ions with an uncertainty of approx.1% or better

  9. Whole-body retention studies of /sup 169/Yb-citrate. Estimation of radiation dose to humans from /sup 169/Yb-citrate

    Energy Technology Data Exchange (ETDEWEB)

    Ando, A; Hiraki, T [Kanazawa Univ. (Japan). School of Paramedicine; Mori, H; Ando, I; Hisada, K

    1977-09-01

    For purpose of the estimation of the radiation dose to humans from /sup 169/Yb-citrate, the whole-body retention studies using five rats were carried out. Following intravenous administration of /sup 169/Yb-citrate, the whole-body activity was monitored for 40 days by the animal counter. The whole-body retention curve consisted of three components: the first with a 3.6 hours effective half-time, the second with an 154 hours effective half-time and the third with a 29.9 days effective half-time. Therefore it was assumed that 32% of the administered /sup 169/Yb-citrate clears from the kidney with a short biologic half-time (3.6 hours), 18% remains in the liver and other soft tissues with a relatively long biologic half-time (194 hours) and 50% remains in the bone with a long biologic half-time (850 days). Based on these biological data and the MIRD Committee method, the average dose to the bone and whole-body were 20.8 rads/mCi and 4.5 rads/mCi respectively.

  10. Polychaeten aus den Zoologischen Museen von Leiden und Amsterdam I

    NARCIS (Netherlands)

    Augener, H.

    1933-01-01

    In der vorliegenden Arbeit ist die Untersuchung eines sehr umfangreichen Polychaeten-Materials niedergelegt, das mir von Herrn Prof. Dr. E. D. van Oort in Leiden und Herrn Prof. Dr. L. F. de Beaufort in Amsterdam zur Bearbeitung übergeben wurde. Von diesem Material ist der dem Museum in Leiden

  11. [Hans Jakob Christoffel von Grimmelshausen. Saksa Simplicissimuse seiklused] / Meelis Friedenthal

    Index Scriptorium Estoniae

    Friedenthal, Meelis, 1973-

    2011-01-01

    Tutvustus: Grimmelshausen, Hans Jakob Christoffel von. Saksa Simplicissimuse seiklused, teisisõnu: ühe veidra vagabundi elulugu, kel Melchior Sternfels von Fuchshaim nimeks, et kus ja mis moel ta siia ilma sündis ning mida siin nägi, õppis, oma nahal tunda sai ja kannatas, nagu sellestki, miks ta siinsest ilmast vabatahtlikult loobub. [Tallinn] : Pegasus, c2010

  12. Von Neumann algebras as complemented subspaces of B(H)

    DEFF Research Database (Denmark)

    Christensen, Erik; Wang, Liguang

    2014-01-01

    Let M be a von Neumann algebra of type II1 which is also a complemented subspace of B( H). We establish an algebraic criterion, which ensures that M is an injective von Neumann algebra. As a corollary we show that if M is a complemented factor of type II1 on a Hilbert space H, then M is injective...

  13. An accurate von Neumann's law for three-dimensional foams

    NARCIS (Netherlands)

    Hilgenfeldt, Sascha; Kraynik, Andrew M.; Koehler, Stephan A.; Stone, Howard A.

    2001-01-01

    The diffusive coarsening of 2D soap froths is governed by von Neumann's law. A statistical version of this law for dry 3D foams has long been conjectured. A new derivation, based on a theorem by Minkowski, yields an explicit analytical von Neumann's law in 3D which is in very good agreement with

  14. Erfahrungen an der Schnittstelle von Medienarbeit und Praxisforschung

    Directory of Open Access Journals (Sweden)

    Peter Holzwarth

    2007-11-01

    Full Text Available Der Beitrag reflektiert die Verbindung von praktischer Medienarbeit und Forschung am Beispiel eines internationalen EU-Forschungsprojekts zum Thema Medien und Migration. Neben didaktischen Prinzipien und Konzepten für die aktive Medienarbeit im Forschungskontext geht es um die Kooperation von medienpädagogischer Begleitung (MB und wissenschaftlicher Begleitung (WB sowie um deren spezifische Kompetenzen.

  15. Die baltischen Kapitulationen von 1710 : Kontext, Wirkungen, Interpretationen / Marten Seppel

    Index Scriptorium Estoniae

    Seppel, Marten, 1979-

    2015-01-01

    Arvustus: Die baltischen Kapitulationen von 1710 : Kontext, Wirkungen, Interpretationen, hrsg. von Karsten Brüggemann, Mati Laur und Pärtel Piirimäe, Queleln und Studien zur baltischen Geschichte, Bd 23 (Köln u.a: Böhlau Verlag, 2014)

  16. Reduction of Kondo lattice effects in Yb1-xLuxAl3 observed by soft x-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Yamaguchi, J; Sekiyama, A; Imada, S; Yamasaki, A; Tsunekawa, M; Muro, T; Ebihara, T; Onuki, Y; Suga, S

    2007-01-01

    We have carried out the bulk-sensitive and high-resolution soft x-ray photoelectron spectroscopy on Lu substituted intermediate-valence compound Yb 1-x Lu x Al 3 (x = 0.4) at temperatures from 200 to 20 K. The temperature dependences of the bulk Yb 4f photoelectron spectra revealed in our preceding works on high purity YbAl 3 have not been observed in this Lu substituted system. The temperature dependences of the bulk Yb 4f peak positions and the Yb valence in this system can be well reproduced by the single impurity Anderson model (SIAM), whereas the spectral behaviors in YbAl 3 were not at all reproduced by the SIAM. These results confirm the importance of the Kondo lattice effects for YbAl 3 , for which the coherent lattice periodicity plays essential roles

  17. [Precocious puberty and von Recklinghausen's disease].

    Science.gov (United States)

    Barg, Ewa; Wikiera, Beata; Basiak, Aleksander; Głab, Ewa

    2006-01-01

    Von Recklinghausen's disease belongs to a group of neurocutaneous syndromes and is characterised by skin, nerve and bone abnormalities. We present a case of von Recklinghausen's disease and precocious puberty in 7-year-old boy. At the age of three café au lait spots on the skin and an incranial tumour situated near the optic chiasm--qualified as inoperable--were discovered. At the age of 7 first signs of precocious puberty appeared (pubic hair P3 and enlargement of the testes (15 ml) and penis). Laboratory measurements included: LH 7.5 mIU/ml, FSH 1.1 mIU/ml, testosterone 183 ng/ml, assessment of bone age: 9 years. The response to LHRH stimulation was characteristic for true precocious puberty (LH 15.9 mIU/ml and FSH 1.5 mIU/ml after 30 minutes). The MRI of the brain showed a tumour of the suprasellar region with compression of pituitary stalk. True precocious puberty was diagnosed. Treatment with Diphereline was introduced. At present the boy is 9 years old and has been treated with Diphereline for 16 months. The volume of the testicles has decreased to 7 ml and loss of pubic hair was noted. The MRI does not show any progression in tumour growth. The authors would like to underline the need of close observation of children with von Reclinghausen disease with regard to possibility of uncovering true precocious puberty which is critical for rapid diagnosis and introduction of correct treatment.

  18. Unlawfulness of environmental zones; Rechtswidrigkeit von Umweltzonen

    Energy Technology Data Exchange (ETDEWEB)

    Balbach, Jan

    2016-07-01

    The author examines the new findings on the effectiveness of the environmental zones and, in this context, questions their legitimacy. In addition, the efforts of the European and German legislators are analyzed in order to reduce the particulate matter pollution. In addition, legal protection against the exceeding of limits for particulate matter is critically appreciated. [German] Der Autor beleuchtet die neuen Erkenntnisse zur Wirksamkeit der Umweltzonen und hinterfragt vor diesem Hintergrund deren Rechtmaessigkeit. Darueber hinaus werden die Bemuehungen des europaeischen und deutschen Gesetzgebers analysiert, um die Feinstaubbelastung zu senken. Zudem wird der Rechtsschutz gegen die Ueberschreitung von Feinstaubgrenzwerten kritisch gewuerdigt.

  19. A Metabiography of Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Nicolaas A. Rupke

    2006-04-01

    Full Text Available Article in English.The author's recently published monograph on Alexander von Humboldt describes the multiple images of this great cultural icon. The book is a metabiographical study that shows how from the middle of the nineteenth century to the present day Humboldt has served as a nucleus of crystallisation for a variety of successive socio-political ideologies, each producing its own distinctive representation of him. The historiographical implications of this biographical diversity are profound and support current attempts to understand historical scholarship in terms of memory cultures.

  20. Die Biopsie von Knochen- und Weichteiltumoren

    OpenAIRE

    Fuchs, B

    2008-01-01

    Technisch stellt die Biopsie von Knochen- und Weichteiltumoren einen simplen Akt dar, intellektuell aber ist die Planung einer Biopsie höchst anspruchsvoll. Zu häufig werden heutzutage immer noch Biopsien unsachgemäss durchgeführt, so dass die Behandlung - im besten Fall - erschwert wird. Eine unsachgemäss durchgeführte Biopsie führt häufig zu negativen funktionellen Konsequenzen für den Patienten, im schlimmsten Fall kann es die Prognose direkt beeinträchtigen. Aus diesem Grund soll...

  1. Die Altäre von Selinunt

    OpenAIRE

    Voigts, Clemens

    2014-01-01

    In der Dissertation wurden die Altäre von Selinunt, einer griechischen Kolonie auf Sizilien, mit den Methoden der Bauforschung untersucht. Die neun behandelten Brandopferaltäre sind monumentale Quaderbauten, die bis zu 20 m Länge erreichen. Sie stammen aus der Blütezeit Selinunts, dem 6. und 5. Jh. v. Chr. Die Bauten waren bereits im 19. und 20. Jh. freigelegt worden und wurden nun in Bauaufnahmen dokumentiert, zeichnerisch rekonstruiert und zeitlich eingeordnet. Dabei ließ sich an ihnen eine...

  2. Alexander von Humboldt’s footnotes

    OpenAIRE

    Werner, Anja

    2015-01-01

    Alexander von Humboldts Fußnoten waren ihrer Zeit weit voraus, obwohl sie kaum den heutigen akademischen Standards entsprechen. Dieser Artikel untersucht die Fußnoten in Humboldts Essai politique sur l‘île de Cuba (1826). Zwar ist es nicht immer leicht, die manchmal recht geheimnisvollen Verweise zu entschlüsseln, dennoch lohnt sich der Versuch: Humboldts Fußnoten geben nicht nur Auskunft über seine umfassenden Netzwerke des Wissens. Sie verweisen auch auf Auseinandersetzungen verschiedener G...

  3. YB-1 facilitates basal and 5-fluorouracil-inducible expression of the human major vault protein (MVP) gene.

    Science.gov (United States)

    Stein, Ulrike; Bergmann, Stephan; Scheffer, George L; Scheper, Rik J; Royer, Hans-Dieter; Schlag, Peter M; Walther, Wolfgang

    2005-05-19

    Vaults have been suggested to play a direct role in multidrug resistance (MDR) to anticancer drugs. The human major vault protein (MVP) also known as lung resistance-related protein (LRP) represents the predominant component of vaults that may be involved in the defense against xenobiotics. Here, we demonstrate that besides MDR-related cytostatics, also the non-MDR-related drug 5-fluorouracil (5-FU) was able to induce MVP mRNA and protein expression. Treatment with 5-FU amplified the binding activity and interaction of the transcription factor Y-box binding protein-1 (YB-1) with the Y-box of the human MVP gene promoter in a time-dependent manner. 5-FU also induced reporter expressions driven by a panel of newly generated MVP promoter deletion mutants. Interestingly, stably YB-1 overexpressing cell clones showed enhanced binding of YB-1 to the Y-box motif, associated with enhanced basal as well as 5-FU-inducible MVP promoter-driven reporter expressions. Moreover, transduction of YB-1 cDNA led to increased expression of endogenous MVP protein. Under physiological conditions, we observed a strong coexpression of MVP and YB-1 in human colon carcinoma specimen. In summary, our data demonstrate a direct involvement of YB-1 in controlling basal and 5-FU-induced MVP promoter activity. Therefore, YB-1 is directly linked to MVP-mediated drug resistance.

  4. Phase formation and stability of quasicrystal/α-Mg interfaces in the Mg–Cd–Yb system

    International Nuclear Information System (INIS)

    Ohhashi, S.; Suzuki, K.; Kato, A.; Tsai, A.P.

    2014-01-01

    Phase formation involving icosahedral quasicrystals (iQc) in the Mg–Cd–Yb system was investigated. The phase diagrams obtained revealed that the iQc is in equilibrium with either (Mg, Cd) 2 Yb or an α-Mg phase over a wide composition range at 673 K. A eutectic reaction, where the melt decomposed to a rod-like lamella structure consisting of iQc and α-Mg phases was observed for Mg 68 Cd 24 Yb 8 at 735 K. High-angle annular dark-field scanning transmission microscopy observation of the iQc in Mg 96 Cd 3 Yb 1 verified the atomic positions of the Yb icosahedra and confirmed that the i-MgCdYb is isostructural to the i-CdYb. The formation of the eutectic structure is responsible for the high stability of the iQc/α-Mg interfaces because of good lattice matching; which is coincident interplanar spacing over several planes for the two phases. This coincidence in interplanar spacing was further confirmed in the real atomic structure, for which the twofold planes of the iQc, and the [0 0 0 2] and [2 −1 −1 0] planes of α-Mg are dominant factors in determining the stability of the interfaces

  5. Luminescence properties of Y2O3:Bi3+, Yb3+ co-doped phosphor for application in solar cells

    Science.gov (United States)

    Lee, E.; Kroon, R. E.; Terblans, J. J.; Swart, H. C.

    2018-04-01

    Bismuth (Bi3+) and ytterbium (Yb3+) co-doped yttrium oxide (Y2O3) phosphor powder was successfully synthesised using the co-precipitation technique. The X-ray diffraction (XRD) patterns confirmed that a single phase cubic structure with a Ia-3 space group was formed. The visible emission confirmed the two symmetry sites, C2 and S6, found in the Y2O3 host material and revealed that Bi3+ ions preferred the S6 site as seen the stronger emission intensity. The near-infrared (NIR) emission of Yb3+ increased significantly by the presence of the Bi3+ ions when compared to the singly doped Y2O3:Yb3+ phosphor with the same Yb3+ concentration. An increase in the NIR emission intensity was also observed by simply increasing the Yb3+ concentration in the Y2O3:Bi3+, Yb3+ phosphor material where the intensity increased up to x = 5.0 mol% of Yb3+ before decreasing due to concentration quenching.

  6. Up conversion luminescence of Yb3+–Er3+ codoped CeO2 nanocrystals with imaging applications

    International Nuclear Information System (INIS)

    Cho, Jung-Hyun; Bass, Michael; Babu, Suresh; Dowding, Janet M.; Self, William T.; Seal, Sudipta

    2012-01-01

    The effects of Yb 3+ doping on up conversion in Yb 3+ –Er 3+ co-doped cerium oxide nanocrystals are reported. Green emission around 545 and 560 nm attributed to the 2 H 11/2 , 4 S 3/2 → 4 I 15/2 transitions and red emission around 660 and 680 nm due to 4 F 9/2 → 4 I 15/2 transitions under 975 nm excitation were studied at room temperature. Both green and red emission intensities increase as the Yb 3+ concentration increases from 0%. Emission strength starts to decrease after the Yb 3+ concentration exceeds a critical amount. The green emission strength peaks around 1% Yb 3+ concentration while the red emission strength peaks around 4%. An explanation of competition between different decay mechanisms is presented to account for the luminescence dependence on Yb 3+ concentration. Also, the application of up converting nanoparticles in biomedical imaging is demonstrated. - Highlights: ► Up conversion in Yb 3+ –Er 3+ co-doped cerium oxide nanocrystals. ► Different decay mechanisms determine luminescence efficiency. ► Up converting nanoparticles in biomedical imaging is demonstrated.

  7. Valence and Magnetic Transitions in YbMn2Ge2-Applied Pressure

    International Nuclear Information System (INIS)

    Hofmann, M.; Link, P.; Campbell, S.J.; Goncharenko, I.

    2005-01-01

    Full text: Rare-earth intermetallic compounds containing ytterbium exhibit a wide range of interesting and unusual physical and magnetic properties. This occurs mainly as a result of their mixed valence states (II/III) or changes from one valence state to the other. We have recently determined the magnetic structures of tetragonal YbMn 2 Ge 2 (I4/mmm) by powder neutron diffraction experiments and demonstrated that YbMn 2 Ge 2 has a planar antiferromagnetic structure below T N1 ∼ 510 K with a canted antiferromagnetic structure below T N2 ∼ 185 K. As applied pressure favours changes in the valence character of intermediate valence systems and correspondingly influences the magnetic behaviour, we have investigated the effects of applied pressure on YbMn 2 Ge 2 . Analyses of our in situ neutron diffraction experiments (T=1.5-300 K; p=0-2.7 GPa), reveal a distinct change in magnetic structure and a sharp drop in the a-lattice parameter above ∼ 1.4 GPa with the changes associated with a valence transition. A full account of these effects will be discussed in relation to our current photoelectron spectroscopy measurements of YbMn 2 Ge 2 . (authors)

  8. Cold beam of isotopically pure Yb atoms by deflection using 1D ...

    Indian Academy of Sciences (India)

    Cold atoms [1], with their long measurement times, promise to revolutionize the field of precision measurements. In this respect, laser-cooled Yb constitutes a useful species because its spin-zero ground state obviates the need for a second re-pumping laser, as is required for laser cooling of the more common spin-half ...

  9. Yb3+:Sr3Y2(BO3)4: A potential ultrashort pulse laser crystal

    International Nuclear Information System (INIS)

    Sun, Shijia; Xu, Jinlong; Wei, Qi; Lou, Fei; Huang, Yisheng; Yuan, Feifei; Zhang, Lizhen; Lin, Zhoubin; He, Jingliang; Wang, Guofu

    2015-01-01

    Highlights: • A Yb 3+ :Sr 3 Y 2 (BO 3 ) 4 crystal was grown successfully by Czochralski method. • The crystal has wide absorption and emission bandwidth. • 3.47 W continuous wave laser output with a slope efficiency of 29% was obtained. • The results show that the crystal is a promising ultrashort pulse laser material. - Abstract: A Yb 3+ :Sr 3 Y 2 (BO 3 ) 4 crystal was grown successfully by the Czochralski method. The polarized spectral properties and continuous wave laser output of this crystal were investigated in detail. The crystal has larger absorption and emission cross sections compared with many mature Yb 3+ -doped borate crystals. The full width at half maximum of the emission bands around 1023 nm are 69 nm (E//a), 61 nm (E//b) and 65 nm (E//c). 3.47 W continuous wave laser output with a slope efficiency of 29% and an optical conversion efficiency of 24% was obtained. The results reveal that Yb 3+ :Sr 3 Y 2 (BO 3 ) 4 crystal is an excellent candidate for ultrashort pulse laser crystal

  10. High-power Yb-doped continuous-wave and pulsed fibre lasers

    Indian Academy of Sciences (India)

    2014-01-05

    Jan 5, 2014 ... In this article, a review of Yb-doped CW and pulsed fibre lasers along with our study on self-pulsing dynamics in CW fibre lasers to find its role in high-power fibre laser development and the physical ... Solid State Laser Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, India ...

  11. Synthesis of Er and Er : Yb doped sol–gel derived silica glass and ...

    Indian Academy of Sciences (India)

    Unknown

    Materials Science Centre, †Central Research Facility, Optical Fibre Unit, Indian Institute of Technology,. Kharagpur 721 302, India. MS received 1 March 2004; revised 4 July 2004. Abstract. Er3+ and Er3+ : Yb3+ doped optical quality, crack and bubble free glasses for possible use in mak- ing laser material have been ...

  12. Thermodynamic modeling of the Eu–Te and Te–Yb systems

    Energy Technology Data Exchange (ETDEWEB)

    Ghamri, H., E-mail: ghamri.houda@hotmail.fr; Djaballah, Y.; Belgacem-Bouzida, A.

    2015-09-15

    Highlights: • The Eu–Te and Te–Yb binary systems were not previously thermodynamically assessed. • The Eu–Te and Te–Yb systems were assessed by using the CALPHAD technique. • A coherent set of thermodynamic parameters was obtained for both systems. • An agreement between the calculated results and experimental data was obtained for both systems. - Abstract: In this work, thermodynamic assessments of the Eu–Te and Te–Yb binary systems were carried out by using the CALculation of PHase Diagrams (CALPHAD) method based on the available experimental data including thermodynamic properties and phase equilibria. Reasonable models were constructed for all the phases of the two systems. The liquid phases were described by the substitutional solution model with the Redlich–Kister polynomial. The three intermetallic compounds, Eu{sub 4}Te{sub 7}, Eu{sub 3}Te{sub 7} and TeYb in the two systems, were treated as stoichiometric phases, while the non-stoichiometric phase (EuTe), which has an homogeneity range, was treated by a two-sublattice model following the schema: (Eu,Te){sub 0.5}(Te){sub 0.5}. A consistent set of thermodynamic parameters leading to reasonable agreement between the calculated results and experimental data was obtained.

  13. Highly Yb-doped KGd(WO4)2 thin-film amplifier

    NARCIS (Netherlands)

    Yong, Yean Sheng; Aravazhi, S.; Vázquez-Córdova, Sergio Andrés; García Blanco, Sonia Maria; Pollnau, Markus

    We report record-high small-signal gain of 1050 dB/cm at 981 nm wavelength in a KGd0.425Yb0.575(WO4)2 thin film. The sensitivity of gain to the shift of beam-focus position, which is critical under non-waveguiding conditions, is investigated.

  14. Unusual antiferromagnetic structure of YbCo{sub 2}Si{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Mufti, N. [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Dresden (Germany); Department of Physics, State University of Malang, Malang (Indonesia); Kaneko, K. [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Dresden (Germany); Quantum Beam Science Center, Japan Atomic Energy Agency, Tokai (Japan); Hoser, A. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany); Gutmann, M. [ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Didcot (United Kingdom); Geibel, C.; Stockert, O. [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Dresden (Germany); Krellner, C. [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Dresden (Germany); Physikalisches Institut, Goethe-Universitaet Frankfurt, Frankfurt (Germany)

    2016-07-01

    We report on extensive powder and single crystal neutron diffraction experiments to study the magnetic structure in YbCo{sub 2}Si{sub 2} below the Neel temperature T{sub N} = 1.7 K in detail. Representation analysis has been used to find the possible magnetic structure models compatible with the experiments. Two different magnetically ordered phases can clearly be distinguished. At lowest temperatures a commensurate magnetic structure with a propagation vector k{sub 1} = (0.25 0.25 1) and equal moments or about 1.4 μ{sub B}/Yb is found, while the intermediate phase (T > 0.9 K) is characterized by an incommensurate amplitude-modulated magnetic structure with k{sub 2} = (0.25 0.086 1). The magnetic structure in YbCo{sub 2}Si{sub 2} is in stark contrast to all other compounds of the RCo{sub 2}Si{sub 2} family (R = rare earth element) likely due to some itineracy of the Yb 4f states being responsible for the magnetism.

  15. Thermal Properties of Transparent Yb-Doped YAG Ceramics at Elevated Temperatures

    Czech Academy of Sciences Publication Activity Database

    Hostaša, J.; Matějíček, Jiří; Nait-Ali, B.; Smith, D.S.; Pabst, W.; Esposito, L.

    2014-01-01

    Roč. 97, č. 8 (2014), s. 2602-2606 ISSN 0002-7820 Institutional support: RVO:61389021 Keywords : yttrium aluminium garnet * Yb:YAG * thermal diffusivity Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 2.610, year: 2014 http://onlinelibrary.wiley.com/doi/10.1111/jace.13015/abstract

  16. 1 CW green self-frequency-doubled Yb:YAl3(BO3)4 laser

    International Nuclear Information System (INIS)

    Dekker, P.; Dawes, J.; Wang, P.; Piper, J.

    2000-01-01

    Full text: We report 1.1 W continuous wave (CW) green output from a 977nm diode-end-pumped self-frequency-doubled Yb:YAB laser, with a diode-to-green optical conversion efficiency of 10%. Wavelength tunability from 513-546nm has been demonstrated

  17. Near-infrared quantum cutting in Yb3+ ion doped strontium vanadate

    Science.gov (United States)

    Sawala, N. S.; Bajaj, N. S.; Omanwar, S. K.

    2016-05-01

    The materials Sr3-x(VO4)2:xYb were successfully synthesized by co-precipitation method varying the concentration of Yb3+ ions from 0 to 0.06 mol. It was characterize by powder X-ray powder diffraction (XRD) and surface morphology was studied by scanning electronic microscope (SEM). The photoluminescence (PL) properties were studied by spectrophotometers in near infra red (NIR) and ultra violet visible (UV-VIS) region. The Yb3+ ion doped tristrontium vanadate (Sr3(VO4)2) phosphors that can convert a photon of UV region (349 nm) into photons of NIR region (978, 996 and 1026 nm). Hence this phosphor could be used as a quantum cutting (QC) luminescent convertor in front of crystalline silicon solar cell (c-Si) panels to reduce thermalization loss due to spectral mismatch of the solar cells. The theoretical value of quantum efficiency (QE) was calculated from steady time decay measurement and the maximum efficiency approached up to 144.43%. The Sr(3-x) (VO4)2:xYb can be potentiality used for betterment of photovoltaic (PV) technology.

  18. Structural and optical properties of novel surfactant-coated Yb-TiO2 nanoparticles

    International Nuclear Information System (INIS)

    Calandra, P.; Lombardo, D.; Pistone, A.; Turco Liveri, V.; Trusso, S.

    2011-01-01

    In this paper a novel hybrid approach to synthesise composite nanoparticles is presented. It is based on the laser ablation of a bulk target (Yb) immersed in a reversed micellar solution which contains nanoparticles of a different host material (TiO 2 nanoparticles) previously synthesised by chemical method. This approach thus exploits the advantages of the chemical synthesis through reversed micellar solution (size control, nanoparticle stabilisation), and of the laser ablation (“clean” synthesis, no side reactions). Central role is played by the microscopic processes controlling the deposition of the ablated Yb atoms onto the surface of TiO 2 nanoparticles which actually behave as nucleation seeds. The structural features of the resulting Yb-TiO 2 composite nanoparticles have been studied by Transmission Electron Microscopy, whereas their peculiar optical properties have been explored by UV–Vis spectroscopy and steady-state fluorescence. Results consistently show the formation of Yb and TiO 2 glued nanodomains to form nearly spherical and non-interacting nanoparticles with enhanced photophysical properties.

  19. Yb3+,Er3+,Eu3+-codoped YVO4 material for bioimaging with dual mode excitation

    International Nuclear Information System (INIS)

    Thao, Chu Thi Bich; Huy, Bui The; Sharipov, Mirkomil; Kim, Jin-Ik.; Dao, Van-Duong; Moon, Ja-Young; Lee, Yong-Ill

    2017-01-01

    We propose an efficient bioimaging strategy using Yb 3+ ,Er 3+ ,Eu 3+ -triplet doped YVO 4 nanoparticles which were synthesized with polymer as a template. The obtained particles possess nanoscale, uniform, and flexible excitation. The effect of Eu 3+ ions on the luminescence properties of YVO 4 :Yb 3+ ,Er 3+ ,Eu 3+ was investigated. The upconversion mechanism of the prepared material was also discussed. The structure and optical properties of the prepared material were characterized by using X-ray diffraction (XRD), Fourier-transform IR spectroscopy (FTIR), scanning electron microscopy (SEM), Transmission electron microscopy (TEM) upconversion and photoluminescence spectra. The Commission International de I′Eclairage (CIE) chromaticity coordinates was investigated to confirm the performance of color luminescent emission. The prepared YVO 4 :Yb 3+ ,Er 3+ ,Eu 3+ nanoparticles could be easily dispersed in water by surface modification with cysteine (Cys) and glutathione (GSH). The aqueous dispersion of the modified YVO 4 :Yb 3+ ,Er 3+ ,Eu 3+ exhibits bright upconversion and downconversion luminescence and has been applied for bioimaging of HeLa cells. Our developed material with dual excitation offers a promising advance in bioimaging. - Highlights: • Prepared particles possess nanoscale size, uniform, and larger scale. • The material exhibits strong emission under dual mode excitations. • The surface material has been applied for bioimaging of HeLa cell. • Low cytotoxicity, no auto-fluorescence

  20. Microscopic analysis of shape transition in neutron-deficient Yb isotopes

    Science.gov (United States)

    Fu, Y.; Tong, H.; Wang, X. F.; Wang, H.; Wang, D. Q.; Wang, X. Y.; Yao, J. M.

    2018-01-01

    The development of nuclear collectivity in even-even Yb-170152 is studied with three types of mean-field calculations: the nonrelativistic Hartree-Fock plus BCS calculation using the Skyrme SLy4 force plus a density-dependent δ pairing force and the relativistic mean-field calculation using a point-coupling energy functional supplemented with either a density-independent δ pairing force or a separable pairing force. The low-lying states are obtained by solving a five-dimensional collective Hamiltonian with parameters determined from the three mean-field solutions. The energy surfaces, excitation energies, electric multiple transition strengths, and differential isotope shifts are presented in comparison with available data. Our results show that different treatments of pairing correlations have a significant influence on the speed of developing collectivity as the increase of neutron number. All the calculations demonstrate the important role of dynamic shape-mixing effects in resolving the puzzle in the dramatic increase of charge radius from 152Yb to 154Yb and the role of triaxiality in Yb 160 ,162 ,164 .

  1. Effect of Yb substitution on room temperature magnetic and dielectric properties of bismuth ferrite nanoparticles

    Science.gov (United States)

    Remya, K. P.; Amirthapandian, S.; Manivel Raja, M.; Viswanathan, C.; Ponpandian, N.

    2016-10-01

    Effect of the Yb dopant on the structural, magnetic, and electrical properties of the multiferroic BiFeO3 have been studied. The structural properties of sol-gel derived Bi1-xYbxFeO3 (x = 0.0, 0.1, and 0.2) nanoparticles reveal the formation of a rhombohedrally distorted perovskite in XRD and a reduction in the average grain size have been observed with an increase in the Yb concentration. Microstructural studies exhibited the formation of sphere like morphology with decreasing particle size with increase in the dopant concentration. The effective doping also resulted in larger magnetization as well as coercivity with the maximum of 257 Oe and 1.76 emu/g in the Bi0.8Yb0.2FeO3 nanoparticles. Ferroelectric as well as dielectric properties of the nanoparticles were also improved on doping. The best results were obtained for the BiFeO3 nanoparticles having Yb concentration x = 0.2.

  2. Modeling of Yb3+-sensitized Er3+-doped silica waveguide amplifiers

    DEFF Research Database (Denmark)

    Lester, Christian; Bjarklev, Anders Overgaard; Rasmussen, Thomas

    1995-01-01

    A model for Yb3+-sensitized Er3+-doped silica waveguide amplifiers is described and numerically investigated in the small-signal regime. The amplified spontaneous emission in the ytterbium-band and the quenching process between excited erbium ions are included in the model. For pump wavelengths...

  3. Tape casting fabrication and properties of planar waveguide YAG/Yb:YAG/YAG transparent ceramics

    Science.gov (United States)

    Zhao, Yu; Liu, Qiang; Ge, Lin; Wang, Chao; Li, Wenxue; Yang, Chao; Wang, Juntao; Yuan, Lei; Xie, Tengfei; Kou, Huamin; Pan, Yubai; Gao, Qingsong; Bo, Yong; Peng, Qinjun; Xu, Zuyan; Li, Jiang

    2017-07-01

    Highly transparent YAG/10at.%Yb:YAG/YAG planar waveguide ceramics were fabricated by the non-aqueous tape casting and solid-state reactive sintering technology. The tapes are relatively homogeneous and the green body shows a dense structure without distinct interfaces after the treatment of debinding and cold isostatic pressing. YAG/10at.%Yb:YAG/YAG ceramics with almost full dense structure were obtained by vacuum-sintering at 1760 °C for 30 h. For the mirror-polished sample with the thickness of 3.5 mm, the In-line transmittance was measured to be 83.6% at the visual wavelength of 400 nm. The diffusion distance of the Yb3+ ions was about 215 μm along the thickness direction of the ceramics. In the lasing experiments, the YAG/10at.%Yb:YAG/YAG planar waveguide ceramics were end-pumped by a 976 nm semiconductor diode laser and enabled efficient continuous-wave lasers, which resulted in a maximum output power of 1.6 W and a slope efficiency of 34.4% at 1030 nm.

  4. Insights into the energy transfer mechanism in Ce3+-Yb3+ codoped YAG phosphors

    NARCIS (Netherlands)

    Yu, D. C.; Rabouw, F. T.|info:eu-repo/dai/nl/413318036; Boon, W. Q.; Kieboom, T.; Ye, S.; Zhang, Q. Y.; Meijerink, A.|info:eu-repo/dai/nl/075044986

    2014-01-01

    Two distinct energy transfer (ET) mechanisms have been proposed for the conversion of blue to near-infrared (NIR) photons in YAG:Ce3+,Yb3+. The first mechanism involves downconversion by cooperative energy transfer, which would yield two NIR photons for each blue photon excitation. The second

  5. Optical bistability in Er-Yb codoped phosphate glass microspheres at room temperature

    NARCIS (Netherlands)

    Warda, Jonathan M.; O'Shea, Danny G.; Shortt, Brian J.; Chormaic, Sile Nic

    2007-01-01

    We experimentally demonstrate optical bistability in Er(3+)-Yb(3+) phosphate glass microspheres at 295 K. Bistability is associated with both Er(3+) fluorescence and lasing behavior, and chromatic switching. The chromatic switching results from an intrinsic mechanism exploiting the thermal coupling

  6. Luminescence dosemeter of the Al{sub 2}O{sub 3}:Er,Yb

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Katia A.; Ventieri, Alexandre; Bitencourt, Jose F.S. [Universidade de Sao Paulo (EP/USP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Eletrica; Mittani, Juan C.R.; Tatumi, Sonia H. [Faculdade de Tecnologia de Sao Paulo (CEETEPS), SP (Brazil)

    2011-07-01

    The present work deals with the thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) properties of {alpha}-Al{sub 2}O{sub 3}: Er,Yb obtained by sol gel process. Nanocrystals formations composed by Er{sub 2}O{sub 3}, Yb{sub 2}O{sub 3} and Yb{sub 3}Al{sub 5}O{sub 12} were observed by TEM images, EDS, electron beam diffraction and RXD, located at the surface of the alumina grains. The sample codoped with 1mol% of Er and 2 mol% of Yb supplied the best results for TL and OSL responses. The growth of the intensity of dosimetric TL peak at 205 deg C was linear with gamma radiation doses and the same behavior was observed in OSL growth curve. The luminescence fading of the sample after a dose of 5 Gy was found initially for a period of 30 days and minimum detectable dose measured for TL was 60.78 mGy and for OSL was 13.09 mGy. (author)

  7. Yb and Er co-doped Y2Ce2O7 nanoparticles: synthesis and ...

    Indian Academy of Sciences (India)

    much attention due to their potential applications in display .... Figure 1. XRD patterns of Yb3+ and Er3+ co-doped Y2Ce2O7 nanoparticles prepared for 4 h at different sintering .... vels relax to the ground 4I15/2 level (You et al 2012). For.

  8. Spectroscopy of Yb-doped tungsten-tellurite glass and assessment of its lasing properties

    Science.gov (United States)

    Merzliakov, M. A.; Kouhar, V. V.; Malashkevich, G. E.; Pestryakov, E. V.

    2018-01-01

    Glasses of the TeO2-WO3-Yb2O3 system are synthesized for wide range of Yb3+ concentrations of up to 6.0 × 1021 ions/cm3. The spectral-luminescent properties of lightly doped samples are investigated at room temperature and at the boiling point of liquid nitrogen. The energies of the Stark levels of the ground and excited states of Yb3+ ions incorporated into tungsten-tellurite glass are determined by analyzing the low-temperature spectra. The absorption, emission, and gain cross section spectra are obtained. The excess of the measured fluorescence decay time over the radiative lifetime ∼0.3 ms derived from the absorption spectra is attributed to the reabsorption effect in bulk samples. Measurements of lightly doped glass powder in the immersion liquid are made to reduce the effect of reabsorption. The fluorescence decay time of the powder is very close to the calculated radiative lifetime. Compared with phosphate, silicate, and other Yb3+-doped glasses, the tungsten-tellurite glass has a promising potential as a gain medium for lasers and amplifiers.

  9. Electronic Spectra of Cs2NaYb(NO2)6: Is There Quantum Cutting?

    Science.gov (United States)

    Luo, Yuxia; Liu, Zhenyu; Hau, Sam Chun-Kit; Yeung, Yau Yuen; Wong, Ka-Leung; Shiu, Kwok Keung; Chen, Xueyuan; Zhu, Haomiao; Bao, Guochen; Tanner, Peter A

    2018-05-03

    The crystal structure and electronic spectra of the T h symmetry hexanitritoytterbate(III) anion have been studied in Cs 2 NaY 0.96 Yb 0.04 (NO 2 ) 6 , which crystallizes in the cubic space group Fm3̅. The emission from Yb 3+ can be excited via the NO 2 - antenna. The latter electronic transition is situated at more than twice the energy of the former, but at room temperature, one photon absorbed at 470 nm in the triplet state produces no more than one photon emitted. Some degree of quantum cutting is observed at 298 K under 420 nm excitation into the singlet state and at 25 K using excitation into either state. The quantum efficiency is ∼10% at 25 K. The energy level scheme of Yb 3+ has been deduced from excitation and emission spectra and calculated by crystal field theory. New improved energy level calculations are also reported for the Cs 2 NaLn(NO 2 ) 6 (Ln = Pr, Eu, Tb) series using the f- Spectra package. The neat crystal Cs 2 NaYb(NO 2 ) 6 has also been studied, but results were unsatisfactory due to sample decomposition, and this chemical instability makes it unsuitable for applications.

  10. Multiple ionization produced in Yb due to N-,Si- and Ti-ion impact

    International Nuclear Information System (INIS)

    Verma, P.

    2000-01-01

    Heavy ion induced inner shell ionization produces multiple vacancies in the outer shells (M, N etc.) simultaneous to vacancies in the inner-shells (viz. L-shell), which in turn create a very complicated electronic configuration. Three projectiles N 2+,3+ , Si 7+,8+ and Ti 10+,11+ ion beams having a range of 0.3 to 3.5 MeV/u were bombarded on a thin rare earth target of Yb. The recorded L X-ray spectra of Yb have been analyzed in the light of multiple ionization produced due to the heavy ion impact. The outer-shell vacancies acting as spectator vacancies cause a shift in the energy of the various L X-ray diagram lines. A comparison of the shifts in the energies of the various L X-ray transitions of Yb due to the impact of these projectiles, from standard values and that due to proton impact along with the deviation of the intensity ratios from single hole branching ratios, reveal a dependence of multiple ionization on the projectile atomic number (Z) and energy. A further comparison of the degree of multiple ionization produced in Yb, evident by the number of spectator vacancies produced due to the impact of projectiles with 7≤Z≤22 and overlapping MeV/u range lead to explicit conclusions regarding the probability of multiple vacancy production in outer shells simultaneous to a single L-shell vacancy for such projectile target combinations. (orig.)

  11. Neutron inelastic scattering experiments on the mixed-valent compound YbCuAl

    International Nuclear Information System (INIS)

    Mattens, W.C.M.; de Boer, F.R.; Murani, A.P.; Lander, G.H.

    1979-01-01

    The dynamical susceptibility of YbCuAl has been established by means of time of flight neutron scattering experiments. Non-Korringa behavior of the quasi-elastic line-width has been found and comparison with NMR data will be given

  12. Up-conversion mechanisms in Er{sup 3+} doped YbAG crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kaczkan, Marcin; Borowska, Maja [Institute of Microelectronics and Optoelectronics PW, Warsaw (Poland); Malinowski, Michal [Institute of Microelectronics and Optoelectronics PW, Warsaw (Poland); Institute of Electronic Materials Technology, Warsaw (Poland); Lukasiewicz, Tadeusz; Kolodziejak, Katarzyna [Institute of Electronic Materials Technology, Warsaw (Poland)

    2009-07-15

    Up-conversion phenomena leading to the red, green and violet emissions in erbium doped ytterbium-aluminum garnet (YbAG) are investigated. Absorption and emission spectra and luminescence dynamics from various excited states of YbAG:Er{sup 3+} were registered. The low temperature absorption spectra were used to determine Stark levels energies of Er{sup 3+} ion in the investigated host. Emissions from the high lying excited states {sup 2}G{sub 9/2}, {sup 4}S{sub 3/2} and {sup 4}F{sub 9/2} of Er{sup 3+} were characterized under pulsed multi-photon IR excitation in the region of wavelength corresponding to the strong {sup 2}F{sub 7/2} {yields} {sup 2}F{sub 5/2} absorption transition of Yb{sup 3+} ions. Using the rate equations formalism the dynamics of the observed emissions were modeled. From the comparison of the measured and calculated decays the energy transfer rates between Yb{sup 3+} and Er{sup 3+} ions were evaluated. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Study of vortex configurations in Yb3Rh4Sn13 via minor hysteresis loops

    International Nuclear Information System (INIS)

    Sarkar, S.; Tulapurkar, A.A.; Ramakrishnan, S.; Grover, A.K.; Tomy, C.V.

    2001-01-01

    The tracings of the minor hysteresis loops in the superconductor Yb 3 Rh 4 Sn 13 (i) elucidate the path dependence in J c (H), (ii) help to reach the stable vortex configuration from a given metastable state and (iii) reveal the occurrence of step change in equilibrium magnetization across the peak effect (PE) regime. (author)

  14. Crystal growth and spectroscopic characterization of Yb3+:LiTaO3

    International Nuclear Information System (INIS)

    Gruber, John B.; Allik, Toomas H.; Sardar, Dhiraj K.; Yow, Raylon M.; Scripsick, Michael; Wechsler, Barry

    2006-01-01

    Spectroscopic properties are presented for Yb 3+ incorporated into single crystals of LiTaO 3 grown by the top-seeded solution growth method. From an analysis of the absorption and fluorescence spectra, we are able to determine the Stark-level components of the 2 F 7/2 (the ground-state multiplet manifold) and the 2 F 5/2 (the excited-state multiplet manifold of Yb 3+ (4f 13 )). The room-temperature fluorescence lifetime of 2 F 5/2 is 678μs as measured on a thin sample to reduce possibilities for reabsorption. Spectral comparisons of Yb 3+ -doped LiTaO 3 and LiNbO 3 are drawn. The crystal-field splitting of Yb 3+ (4f 13 ) in both crystal hosts is modeled using a set of crystal-field splitting parameters, B nm , determined from a recent spectroscopic analysis of Er 3+ (4f 11 ) in LiNbO 3 . Without adjustment of the B nm parameters, the model predicts the Stark-level energy and the symmetry label for each level in reasonable agreement with the experimental values. Less photorefractive than its niobate cousin, LiTaO 3 has potential for use in numerous integrated electro-optical circuits and devices

  15. Re-appraisal of the P, T-odd interaction constant Wd in YbF ...

    Indian Academy of Sciences (India)

    ... Lecture Workshops · Refresher Courses · Symposia · Live Streaming. Home; Journals; Pramana – Journal of Physics; Volume 73; Issue 3. Re-appraisal of the , -odd interaction constant d in YbF: Relativistic configuration interaction approach. Malaya K Nayak Rajat K Chaudhuri. Volume 73 Issue 3 September 2009 ...

  16. High efficiency laser action in mildly doped Yb:LuYAG ceramics

    Czech Academy of Sciences Publication Activity Database

    Pirri, A.; Toci, G.; Li, J.; Xie, T.; Pan, Y.; Babin, Vladimir; Beitlerová, Alena; Nikl, Martin; Vannini, M.

    2017-01-01

    Roč. 73, Nov (2017), s. 312-318 ISSN 0925-3467 Institutional support: RVO:68378271 Keywords : laser ceramic s * Yb laser * mixed garnets * LuYAG Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 2.238, year: 2016

  17. Influence of radiation damage evolution on lattice-location, measurements for Yb and Au in iron

    International Nuclear Information System (INIS)

    Cohen, C.; Abel, F.; Bruneaux, M.; Thome, L.; Bernas, H.; Chaumont, J.

    1978-01-01

    The influence of radiation damage on lattice-location of heavy impurities (Yb and Au) implanted in iron is studied by channeling experiments. The nature of the impurity-radiation damage interaction has been modified by annealing of room-temperature implanted samples or high temperature implantation. The value of the corrected extinction ratio epsilon measured in several crystallographic directions on room-temperature implanted Yb and Au impurities cannot be interpreted uniquely in terms of different site populations. The annealing and implantation temperature dependences of the ratio epsilon for Yb-implanted Fe are very different. Upon annealing, the value of epsilon is unchanged up to 420 0 C and then drops abruptly. In hot-implant experiments, the extinction ratio starts to fall at approximately 150 0 C when vacancies become mobile. Vacancy-assisted diffusion is suggested to cause the changes of epsilon in both experiments. The temperature dependence of epsilon for the (100) plane is found to differ from that in other directions. This planar effect suggests that Yb impurities move preferentially in the (100) plane, which is the plane of vacancy-loops in Fe. A quantitative analysis of these lattice-location results and of related hyperfne interaction results is presented in a companion paper

  18. Indium-modified Yb:KLu(WO{sub 4}){sub 2} crystal: Growth, spectroscopy and laser operation

    Energy Technology Data Exchange (ETDEWEB)

    Serres, J.M. [Física i Cristallografia de Materials i Nanomaterials (FiCMA-FiCNA), Universitat Rovira i Virgili (URV), Campus Sescelades, c/ Marcellí Domingo, s/n., Tarragona E-43007 (Spain); Mateos, X., E-mail: xavier.mateos@urv.cat [Física i Cristallografia de Materials i Nanomaterials (FiCMA-FiCNA), Universitat Rovira i Virgili (URV), Campus Sescelades, c/ Marcellí Domingo, s/n., Tarragona E-43007 (Spain); Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 2A Max-Born-Str., Berlin D-12489 (Germany); Loiko, P. [ITMO University, 49 Kronverkskiy pr., St. Petersburg 197101 (Russian Federation); Griebner, U.; Petrov, V. [Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 2A Max-Born-Str., Berlin D-12489 (Germany); Yumashev, K. [Center for Optical Materials and Technologies (COMT), Belarusian National Technical University, 65/17 Nezavisimosti Ave., Minsk 220013 (Belarus); Aguiló, M.; Díaz, F. [Física i Cristallografia de Materials i Nanomaterials (FiCMA-FiCNA), Universitat Rovira i Virgili (URV), Campus Sescelades, c/ Marcellí Domingo, s/n., Tarragona E-43007 (Spain)

    2017-03-15

    We report on the growth, spectroscopic and laser characterization of a novel monoclinic laser crystal, Yb,In:KLu(WO{sub 4}){sub 2} (Yb,In:KLuW). The absorption, stimulated-emission and gain cross-section spectra of 3.5 at% Yb, 5.5 at% In-doped KLuW are determined at room temperature with polarized light and compared with those for Yb,In:KYW, as well as singly Yb-doped KLuW and KYW crystals. It is found that the introduction of In results in a decrease of the transition cross-sections and in a spectral broadening of the absorption and emission bands. Such a broadening is more pronounced for light polarization E ||N{sub p}. For Yb,In:KLuW, the maximum σ{sub abs} is 9.9×10{sup –20} cm{sup 2} at 980.9 nm for E ||N{sub m} and the corresponding bandwidth of the absorption peak is 3.7 nm. The radiative lifetime for Yb{sup 3+} ions is 237±5 µs. The stimulated-emission cross-sections are σ{sub SE}(m)=2.4×10{sup –20} cm{sup 2} at 1022.4 nm and σ{sub SE}(p)=1.3×10{sup –20} cm{sup 2} at 1039.1 nm corresponding to an emission bandwidth of >30 nm and >35 nm, respectively. The diode-pumped N{sub g}-cut Yb,In:KLuW microchip laser generated 4.11 W at 1042–1048 nm with a slope efficiency of 78%. The Yb,In:KLuW crystal is very promising for the generation of sub-100 fs pulses in mode-locked lasers due to its broadband emission characteristics.

  19. Luminescence properties of Yb:Nd:Tm:KY3F10 nanophosphor and thermal treatment effects

    International Nuclear Information System (INIS)

    Gomes, Laércio; Linhares, Horácio Marconi da Silva M.D.; Ichikawa, Rodrigo Uchida; Martinez, Luis Gallego; Ranieri, Izilda Marcia

    2015-01-01

    In this work, we present the spectroscopic properties of KY 3 F 10 (KY3F) nanocrystals activated with thulium and codoped with ytterbium and neodymium ions. The most important processes that lead to the thulium upconversion emissions in the blue region were identified. A time-resolved luminescence spectroscopy technique was employed to measure the luminescence decays and to determine the most important mechanisms involved in the upconversion process that populates 1 G 4 (Tm 3+ ) excited states. Analysis of the energy-transfer processes dynamics using selective pulsed-laser excitations in Yb:Nd:Tm, Nd:KY3F nanocrystals shows that the direct energy transfer from Nd 3+ to Tm 3+ ions is the mechanism responsible for the 78% of the blue upconversion luminescence in the Yb:Nd:Tm:KY3F when compared with the Yb:Nd:Tm:KY3F bulk crystal for an laser excitation at 802 nm. An investigation of the 1 G 4 level luminescence kinetic of Tm 3+ in Yb/Nd/Tm system revealed that the luminescence efficiency ( 1 G 4 ) starts with a very low value (0.38%) for the synthesized nanocrystal (as grown) and strongly increases to 97% after thermal treatment at 550 °C for 6 h under argon flow. As a consequence of the thermal treatment at T=550 °C, the contributions of the (Nd×Tm) (Up 1 ) and (Nd×Yb×Tm) (Up 2 ) upconversion processes to the 1 G 4 luminescence are 33% (Up 1 ) and 67% for Up 2 . Up 2 process represented by Nd 3+ ( 4 F 3/2 )→Yb 3+ ( 2 F 7/2 ) followed by Yb 3+ ( 2 F 5/2 )→Tm ( 3 H 4 )→Tm 3+ ( 1 G 4 ) was previously reported as the main mechanism to produce the blue luminescence in Yb:Nd:Tm:YLiF 4 and KY 3 F 10 bulk crystals. Results of X-ray diffraction analysis of nanopowder using the Rietveld method reveled that crystallite sizes remain unchanged (12–14 nm) after thermal treatments with T≤400 °C, while the 1 G 4 luminescence efficiency strongly increases from 0.38% (T=25 °C) to 12% (T=400 °C). Results shown that the Nd 3+ ions distribution has a concentration

  20. [Heinz von zur Mühlen. Das Bürgertum Fordert Blut. Ein Bolschewistiches Flugblatt von 1918] / Paul Kaegbein

    Index Scriptorium Estoniae

    Kaegbein, Paul

    2007-01-01

    Arvustus: Heinz von zur Mühlen. Das Bürgertum Fordert Blut. Ein Bolschewistiches Flugblatt von 1918. In : Ostseeprovinzen, baltische Staaten und das Nationale. Münster : LIT, 2005, lk. 403-414. 1918. aastast pärit lendlehest, mille käekirja järgi otsustades on kirjutanud Viktor Kingissepp

  1. Systematic analysis of hot Yb{sup *} isotopes using the energy density formalism

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Deepika; Sharma, Manoj K.; Rajni [Thapar University, School of Physics and Materials Science, Patiala (India); Kumar, Raj [University of Padova, Department of Physics and Astronomy, Padova (Italy); Gupta, Raj K. [Panjab University, Department of Physics, Chandigarh (India)

    2014-10-15

    A systematic study of the spin-orbit density interaction potential is carried out, with spherical as well as deformed choices of nuclei, for a variety of near-symmetric and asymmetric colliding nuclei leading to various isotopes of the compound nucleus Yb{sup *}, using the semiclassical extended Thomas-Fermi formulation (ETF) of the Skyrme energy density formalism (SEDF). We observe that the spin-orbit density interaction barrier height (V{sub JB}) and barrier position (R{sub JB}) increase systematically with the increase in number of neutrons in both the projectile and target, for spherical systems. On allowing deformation effects with optimum orientations, the barrier-height increases by a large order of magnitude, as compared to the spherical case, in going from {sup 156}Yb{sup *} to {sup 172}Yb{sup *} nuclear systems formed via near-symmetric Ni+Mo or asymmetric O+Sm colliding nuclei, except that for the oblate-shaped nuclei, the V{sub JB} is the highest and R{sub JB} shifts towards a smaller (compact) interaction radius. The temperature does not change the behavior of spin-orbit density dependent (V{sub J}) and independent (V{sub P}) interaction potentials, except for some minor changes in the magnitude. The orientation degree of freedom also plays an important role in modifying the barrier characteristics and hence produces a large effect on the fusion cross section. The fusion excitation function of the compound nuclei {sup 160,} {sup 164}Yb{sup *} formed in different incoming channels, show clearly that the new forces GSkI and KDE0v1 respond better than the old SIII force. Among the first two, KDE0v1 seems to perform better. The fusion cross-sections are also predicted for a few other isotopes of Yb{sup *}. (orig.)

  2. Hydrothermal synthesis and upconversion luminescent properties of YVO4:Yb3+,Er3+ nanoparticles

    International Nuclear Information System (INIS)

    Liang, Yanjie; Chui, Pengfei; Sun, Xiaoning; Zhao, Yan; Cheng, Fuming; Sun, Kangning

    2013-01-01

    Graphical abstract: YVO 4 :Yb 3+ ,Er 3+ nanoparticles have been successfully prepared via a facile hydrothermal technique in the presence of citric acid as a complexing agent followed by a subsequent heat treatment process. The PL intensity of the sample increases with the increase of annealing temperature and excitation power. Under the excitation of a 980 nm diode laser, the samples show bright green luminescence. Highlights: ► YVO 4 :Yb 3+ ,Er 3+ nanoparticles were prepared by a hydrothermal approach. ► Bright green luminescence is observed under the excitation of a 980 nm laser diode. ► The PL intensity increases with the increase of annealing temperature. ► Energy transfer properties between Yb 3+ ion and Er 3+ ion were analyzed. -- Abstract: In this paper, YVO 4 :Yb 3+ ,Er 3+ nanoparticles have been successfully prepared via a facile hydrothermal technique in the presence of citric acid as a complexing agent followed by a subsequent heat treatment process. The nanostructures, morphologies and upconversion luminescent properties of the as-prepared YVO 4 :Yb 3+ ,Er 3+ upconverting nanoparticles were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoluminescent (PL) spectra. XRD results indicate that all the diffraction peaks of samples can be well indexed to the tetragonal phase of YVO 4 . TEM images demonstrate that the samples synthesized hydrothermally consist of granular-like nanoparticles ranging in size from about 30 to 50 nm. After being calcined at 500–800 °C for 2 h, the grain sizes of nanoparticles increase slightly. Additionally, the as-prepared nanoparticles show bright green luminescence corresponding to the 2 H 11/2 → 4 I 15/2 and 4 S 3/2 → 4 I 15/2 transitions of Er 3+ ions under the excitation of a 980 nm diode laser, which might find potential applications in fields such as phosphor powders, infrared detection and display devices

  3. Spectroscopic properties of Yb3+ and Er3+ ions in heavy metal glasses

    International Nuclear Information System (INIS)

    Pisarski, Wojciech A.; Grobelny, Lukasz; Pisarska, Joanna; Lisiecki, Radoslaw; Ryba-Romanowski, Witold

    2011-01-01

    Highlights: → Heavy metal glasses doubly doped with Yb 3+ and Er 3+ were examined. → NIR luminescence at about 1530 nm and green and red up-conversion spectra were detected. → The unusual large spectral linewidth nearly close to 110 nm for 4 I 13/2 - 4 I 15/2 transition of Er 3+ ions in Yb-Er co-doped lead borate glass was obtained. → Long-lived NIR luminescence was detected in lead germanate glass. → The NIR luminescence and up-conversion phenomena strongly depend on stretching vibrations of glass host. - Abstract: Selected heavy metal glasses containing Yb 3+ and Er 3+ ions have been studied. Near-infrared luminescence spectra at 1.53 μm and up-conversion spectra of Er 3+ ions were registered under excitation of Yb 3+ ions by 975 nm diode laser line. The luminescence bands correspond to 4 I 13/2 - 4 I 15/2 (NIR), 4 S 3/2 - 4 I 15/2 (green) and 4 F 9/2 - 4 I 15/2 (red) transitions of Er 3+ , respectively. The optical transitions of rare earth ions have been examined as a function of glass host. The unusual large spectral linewidth nearly close to 110 nm for 4 I 13/2 - 4 I 15/2 transition of Er 3+ ions in Yb-Er co-doped lead borate glass was obtained, whereas long-lived NIR luminescence at 1.53 μm was detected in lead germanate glass. The NIR luminescence and up-conversion phenomena strongly depend on stretching vibrations of glass host, which was confirmed by FT-IR spectroscopy.

  4. Influence of temperature on Yb:YAG/Cr:YAG microchip laser operation

    Science.gov (United States)

    Šulc, Jan; Eisenschreiber, Jan; Jelínková, Helena; Nejezchleb, Karel; Å koda, Václav

    2017-02-01

    The goal of this work was an investigation of the temperature influence (in range from 80 up to 320 K) on the laser properties of Yb:YAG/Cr:YAG Q-switched diode-pumped microchip laser. This laser was based on monolith crystal (diameter 3mm) which combines in one piece an active laser part (Yb:YAG crystal, 10 at.% Yb/Y, 3mm long) and saturable absorber (Cr:YAG crystal, 1.36mm long, initial transmission 90% @ 1031 nm). The laser resonator pump mirror (HT for pump radiation, HR for generated radiation) was directly deposited on the Yb:YAG monolith part. The output coupler with reflection 55% for the generated wavelength was placed on the Cr:YAG part. The microchip laser was placed in the temperature controlled cupreous holder inside vacuum chamber of the liquid nitrogen cryostat. For Yb:YAG part longitudinal pulsed pumping (pumping pulse length 2.5 ms, rep-rate 20 Hz, power amplitude 21W) a fibre coupled (core diameter 400 μm, NA= 0:22) laser diode, operating at wavelength 933 nm, was used. The microchip laser mean output power, pulse duration, repetition rate, emission wavelength, and laser beam profile were measured in dependence on temperature. The generated pulse length was in range from 2.2 ns to 1.1 ns (FWHM) with the minimum at 230 K. The single pulse energy was peaking (0.4 mJ) at 180 K. The highest peak power (325 kW) was obtained at 220 K. The highest pulse repetition rate (38 kHz) and output mean power (370mW) was reached for temperature 80 K.

  5. Hyper-O-GlcNAcylation of YB-1 affects Ser102 phosphorylation and promotes cell proliferation in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qingqing [Department of Gastroenterology, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province (China); Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, 19 Qi-xiu Road, Nantong 226001, Jiangsu Province (China); Tao, Tao [Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, 19 Qi-xiu Road, Nantong 226001, Jiangsu Province (China); Liu, Fang [Key Laboratory of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu Province (China); Ni, Runzhou [Department of Gastroenterology, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province (China); Lu, Cuihua, E-mail: lch1516@yeah.net [Department of Gastroenterology, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province (China); Shen, Aiguo, E-mail: shag@ntu.edu.cn [Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, 19 Qi-xiu Road, Nantong 226001, Jiangsu Province (China); Key Laboratory of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu Province (China)

    2016-12-10

    As an essential post-translational modification, O-GlcNAcylation has been thought to be able to modulate various nuclear and cytoplasmic proteins and is emerging as a key regulator of multiple biological processes, such as transcription, cell growth, signal transduction, and cell motility. Recently, authoritative glycomics analyses have reported extensive crosstalk between O-GlcNAcylation and phosphorylation, which always dynamically interplay with each other and regulate signaling, transcription, and other cellular processes. Also, plentiful studies have shown close correlation between YB-1 phosphorylation and tumorigenesis. Therefore, our study aimed to determine whether YB-1 was O-GlcNAc modified and whether such modification could interact with its phosphorylation during the process of HCC development. Western blot and immunohistochemistry were firstly conducted to reveal obvious up-regulation of YB-1, OGT and O-GlcNAc modification in HCC tissues. What is more, not only YB-1 was identified to be O-GlcNAcylated but hyper-O-GlcNAcylation was demonstrated to facilitate HCC cell proliferation in a YB-1 dependent manner. Moreover, we detected four specific O-GlcNAc sites and confirmed T126A to be the most effective mutant in HCC cell proliferation via close O-GlcNAcylation-phosphorylation interaction. Even more interestingly, we discovered that T126A-induced HCC cell retardation and subdued transcriptional activity of YB-1 could be partially reversed by T126A/S102E mutant. From all above, it is not difficult to find that glycosylated-YB-1 mainly enhanced cell proliferation through congenerous actions with YB-1 phosphorylation and thus played indispensable roles in fine-tuning cell proliferation and procession of HCC. - Highlights: • YB-1 and OGT are associated with HCC prognosis. • YB-1 is O-GlcNAc modified in HCC. • Hyper-O-GlcNAcylation promotes HCC cell proliferation in dependent of YB-1. • The proliferating role of O-GlcNAcylation is based on Ser102

  6. Multielement (P-Yb-Zr-Ce-Al-Ca) fiber for moderate-power laser application with enhanced photodarkening resistivity

    Energy Technology Data Exchange (ETDEWEB)

    Dhar, Anirban; Paul, Mukul Chandra [CSIR-Central Glass and Ceramic Research Institute, 196 Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032 (India); Das, Shyamal; Reddy, Pinninty Harshavardhan; Siddiki, Salim H.; Dutta, Debjit; Pal, Mrinmay [Academy of Scientific and Innovative Research (AcSIR), CSIR-CGCRI Campus, Kolkata 700 032 (India); Kir' yanov, Alexander V. [Centro de Investigaciones en Optica, Loma del Bosque 115, Col. Lomas del Campestre, Leon 37150, Guanajuato (Mexico)

    2017-06-15

    Multielement (ME) (P-Yb-Zr-Ce-Al-Ca) nanophase separated silica-glass-based optical fiber is fabricated through a conventional-modified chemical vapor deposition (MCVD) process, coupled with solution doping technique. The lasing and photodarkening behaviors of this ME fiber have been demonstrated and compared, in terms of its photodarkening (PD) performance at moderate pump powers (tens of Watts), with standard Yb-doped fiber with phospho-alumino-silicate (PAS) glass composition, which clearly reveals that the ME-Yb doped fiber is a promising candidate for laser applications with enhanced PD resistivity. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Guy von Dardel 1919-2009

    CERN Multimedia

    2009-01-01

    Guy von Dardel, a well-known figure at CERN and in the international particle physics community, passed away on 28 August. Guy von Dardel came to CERN when it was founded in 1954 and was a full-time staff member until 1964, performing several experiments and working on technical developments. These included the first measurement of the neutral pion’s life-time. Called to Lund University in 1964, he became professor there in 1965 and director of the 1.2 GeV electron accelerator. In the late 1960s, he performed an experiment at CERN’s PS that measured the decays of the Λ. Then, in the early 1970s, he involved the Lund group in a series of experiments at the Intersecting Storage Rings (ISR), where he measured the production of various types of particles. In particular, he participated in a series of experiments that observed the production of a high abundance of particles with large transverse momenta. This required an explanation...

  8. Translational Medicine Advances in von Willebrand Disease

    Science.gov (United States)

    Lillicrap, David

    2014-01-01

    Following the recognition of von Willebrand disease (VWD) in 1926 and the cloning of the gene for von Willebrand factor (VWF) in 1985, significant advances have been made in our fundamental knowledge of both the disease and the protein. Some of this new knowledge has also begun to impact the clinical management of VWD. First, the progressive increase in our understanding of the molecular genetic basis of VWD has resulted in rational applications of molecular testing to complement the current range of phenotypic tests for VWD. These molecular genetic strategies are most effectively directed at the prenatal diagnosis of type 3 VWD and confirmatory testing for types 2B and 2N disease. In contrast, the use of molecular testing to clarify the diagnosis of type 1 VWD is of marginal benefit, at best. In terms of VWD therapies, a new recombinant VWF concentrate has recently completed successful clinical trials and is now awaiting more widespread application. There have even been some pre-clinical successes with VWF gene transfer although the clinical rationale for this therapeutic strategy needs careful consideration. Much more remains to be learnt about the biology of VWF and further translational advances for the enhancement of VWD care will inevitably be realized. PMID:23809112

  9. Die Krakauer Kirche von Karmeliten und Karmelitaninnen

    Directory of Open Access Journals (Sweden)

    Józef Szymon Wronski

    2004-12-01

    Full Text Available 1. Die Klosterkirche der unbeschuhten Karmelitinnen Zum Heiligen Josef. Ein glücklicher Auftakt und somit die charakteristische Einführung in das 20. Jh. für den Kirchenbau von Krakau war die Errichtung der Karmeliterinnen St. Josephs-Kirche an der Lobzowska-Straße 40, in der die Architekten (Tadeusz Stryjeński (1849-1943 - Projektant der Kirche und Franciszek Mączyński (1874-1947 - Ausführer des Bauprojektes mit eigenen Verbesserungen die historisch- eklektizistischen Formen d.h. die mittelalterlichen Formen vor allem des sog. Übergangsstils vereinfachten. Die Kirche, die in den Jahren 1903-1905 errichtet wurde, steht inmitten vom Baukomplex des Klosters, dessen Grundriss das Quadrat ist49. Der Kirchenbau ist ein dem Gesamtbau des Klosters eingefügter Längsraum. Hinter dem Chor liegt das Oratorium des Konvents. Das Material Backstein (mit Verwendung von Stein erinnert an die Baukunst eines der besten Architekten jener Zeit, nämlich Teodor Talowskis (1857-1910, der viele Kirchen in Südpolen, aber auch viele Bürgerhäuser nicht nur in Krakau im ausgehenden 19. Jh. baute. Die Architektur der Karmeliterinnen St. Josephs-Kirche ist immer noch im Malerischen begriffen. Aber die Vereinfachung der historischen Formen führt zu ihrer „Beruhigung” und dadurch zur Wuchtigkeit des Ausdrucks. Bemerkenswert ist die in dieser Zeit (in der Anlage noch seltene ausgewogene Proportionierung des Baukörpers. Das methodische Prinzip jener Zeit ist der Kontrast. Im Kontrast zu den gedrungenen und wuchtigen Formen des Baukörpers stehen z.B. die sich verjüngenden obeliskenförmigen und pylonenartigen Türmchen, die nicht nur die Eingangsfassade der Kirche flankieren, sondern auch an den Ecken des Querhauses der Kirche stehen. Die ingravierten weißen Steine an der Fassade in der Zahl von Zehn erinnern an das Gebot des Karmelterinnenordens: Bete täglich den Rosenkranz und sind zugleich ein Vanitativmotiv. 2. Die Klosterkirche der unbeschuhten

  10. Suitability of tracers; Eignung von Tracern

    Energy Technology Data Exchange (ETDEWEB)

    Klotz, D. [GSF - Forschungszentrum fuer Umwelt und Gesundheit GmbH, Neuherberg (Germany). Inst. fuer Hydrologie

    1999-02-01

    Hydrological tracer techniques are a means of making statements on the direction and speed of underground water. One of the simpler tasks is to find out whether there is hydrological communication between two given points. This requires a determination of the direction of flow, which places less exacting demands on the properties of the tracer than does the task of determining the flow velocity of underground water. Tracer methods can serve to infer from flow velocity the distance (flow) velocity, which is defined as the ratio between the distance between two points located in flow direction and the actual time it takes water to flow from one to the other. [Deutsch] Mit Hilfe der hydrologischen Markierungstechniken koennen Aussagen ueber die Richtung und die Geschwindigkeit von Bewegungen des unterirdischen Wassers gemacht werden. Der einfachere Fall liegt vor, wenn festgestellt werden soll, ob zwischen zwei Punkten eine hydrologische Verbindung besteht. Bei dieser Fliessrichtungsbestimmung sind die Forderungen an die Eigenschaften der einzusetzenden Tracer geringer als bei der Bestimmung der Geschwindigkeit des unterirdischen Wassers. Von den Geschwindigkeiten des unterirdischen Wassers ist die Abstands-(Fliess)geschwindigkeit, die definiert ist durch das Verhaeltnis aus dem Abstand und der wahren Fliesszeit zwischen zwei in Bewegungsrichtung gelegenen Punkten, durch Tracermethoden zu bestimmen. (orig.)

  11. Kontextualisierung von Queer Theory Contextualizing Queer Theory

    Directory of Open Access Journals (Sweden)

    Anna Voigt

    2008-03-01

    Full Text Available Christine M. Klapeer legt in diesem Einführungsband dar, aus welchen politischen und theoretischen Kontexten heraus sich ‚queer‘ zu einem Begriff mit besonderem politischem und theoretischem Gehalt entwickelt hat. Wesentlich zielt sie dabei auf eine kritische Kontextualisierung von „queer theory”. Die Autorin geht zunächst auf das Gay Liberation Movement ein, grenzt die Queer Theory vom Poststrukturalismus, von feministischen Theorien und den Lesbian and Gay Studies ab, beleuchtet Eckpunkte queeren Denkens und zeichnet schließlich die Entwicklungen in Österreich sowohl politisch-rechtlich als auch bewegungsgeschichtlich und in der Wissenschaftslandschaft nach.Christine M. Klapeer’s introductory volume demonstrates the manner in which ‘queer’ grew out of various political and theoretical contexts to become a term with special political and theoretical content. She focuses primarily on a critical contextualization of “queer theory.” The author begins by approaching the Gay Liberation Movement and then distinguishes Queer Theory from poststructuralism, from feminist theories, and from Lesbian and Gay Studies. She continues on to illuminate the key aspects of queer thought and concludes by sketching the development in Austria in terms of politics and the law, the history of movements, and within the landscape of knowledge.

  12. Ferromagnetic correlations in Yb based heavy fermions probed by NMR relaxation: YbNi{sub 4}P{sub 2} vs. Yb(Rh,Ir){sub 2}Si{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Baenitz, M.; Sarkar, R.; Khuntia, P.; Krellner, C.; Geibel, C.; Steglich, F. [Max - Planck Institute of Chemical Physics of Solids, 01187 Dresden, Germany (Germany)

    2012-07-01

    Intersite correlations in Ce-based heavy fermion systems close to the quantum critical point separating the magnetic ordered state from the paramagnetic Kondo lattice are in almost all cases predominantly antiferromagnetic (AFM) in nature. The NMR relaxation of these systems show an evolution from localized fluctuations with 1/T{sub 1} nearly constant above the Kondo temperature T{sub K}, to a linear in T Korringa- like behavior with a constant and enhanced (1/T{sub 1}T)- value below T{sub K}. We report on {sup 31}P-NMR results on the ferromagnetic (FM) quantum critical system YbNi{sub 4}P{sub 2} over a wide range in temperature (2-300 K) and field (0.2 - 9 T). Here, {sup 31}(1/T{sub 1}T)(T) does not show such a signature at T{sub K}, instead a continuous increase of (1/T{sub 1}T) down to lowest T is observed. A similar behavior has been reported for YbRh{sub 2}Si{sub 2}, which also exhibits strong FM correlations evidenced by {sup 29}Si - NMR and an enhanced Wilson ratio. Furthermore, in CeFePO, which is likely unique among Ce-based quantum critical system because of its strong FM correlations, (1/T{sub 1}T) also diverges continuously for T {yields}0. This suggests that the difference in the relaxation between most of the Ce systems and the Yb systems is predominantly related to a change from AFM to FM intersite correlations. NMR-results (shift, line width, T{sub 1}) are analyzed and discussed in different models (Korringa, Moriya).

  13. Ludwig Leichhardt und Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Aliya-Katarina Südfels

    2012-10-01

    Full Text Available Zusammenfassung Im Juli des Jahres 1841 kommt es zu einem Treffen zwischen zwei Männern, das zunächst belanglos erscheint, sich aber Jahre später als wichtige historische Begebenheit herausstellen wird. In seinem Pariser Büro empfängt der 71jährige Naturforscher Alexander von Humboldt den jungen Preußen Ludwig Leichhardt. Der angehende Naturwissenschaftler erhofft sich Zuspruch und Empfehlung des berühmten Alexander von Humboldts. Die Unterredung ist kurz und verläuft für Leichhardt ergebnislos. Es wird das einzige Treffen der beiden Naturwissenschaftler bleiben. Aus heutiger Sicht unverständlich, da Ludwig Leichhardt und Alexander von Humboldt mehr verband, als ihre Leidenschaft für die Naturwissenschaften. Viel zu wenig ist sich bis jetzt den biographischen Analogien und den vergleichbaren geographischen Leistungen der beiden Preußen gewidmet worden. Abstract During July 1841 a meeting between two men takes place, which seems to have been extraneous, but turns out to be a significant historical incident. 71 year old natural scientist Alexander von Humboldt welcomes young Ludwig Leichhardt from Prussia in his office in Paris. The prospective young scientist expects help and references from famous Alexander von Humboldt. The conversation is short and ends from Leichhardt’s point of view without results. Unfortunately this is going to be the only meeting between the two scientists even though the two Prussians have more in common than their passion for the natural sciences. Way too seldomly have biographical analogy and geographical productivity of the two men been compared. Résumé En juillet 1841 une rencontre entre deux hommes a lieu, qui au premier abord semble sans importance, mais qui des années plus tard est considéré comme un événement historique majeur. Dans son bureau parisien, le naturaliste Alexandre de Humboldt, alors âgé de 71 ans, reçoit le jeune Prussien Ludwig Leichhardt. Le jeune scientifique en devenir

  14. CD31-Expression am Primärtumor und Nachweis hämatogen disseminierter Tumorzellen im Knochenmark von Brustkrebspatientinnen

    OpenAIRE

    Eisenmann, Petra

    2005-01-01

    Der Nachweis von disseminierten Tumorzellen im Knochenmark von Patientinnen mit primärem Mammakarzinom ist ein wichtiger prognostischer Parameter. In der vorliegenden Arbeit wurde der Nachweis von CD31 am Primärtumor Mammakarzinom mit dem Auftreten von Mikrometastasen im Knochenmark korreliert. Ferner wurde die prognostische Bedeutung von disseminierten Tumorzellen im Knochenmark und die prognostische Bedeutung von CD31 evaluiert. Bei 50 Patientinnen des Gesamtkollektivs von 195 (25,6%) wu...

  15. Growth and continuous-wave laser operation of disordered crystals of Yb3+:NaLa(WO4)2 and Yb3+:NaLa(MoO4)2

    International Nuclear Information System (INIS)

    Liu, J.; Rico, M.; Griebner, U.; Petrov, V.; Cano-Torres, J.M.; Cascales, C.; Esteban-Betegon, F.; Serrano, M.D.; Volkov, V.; Zaldo, C.

    2005-01-01

    Single crystals of disordered NaLa(WO 4 ) 2 and NaLa(MoO 4 ) 2 doped with Yb 3+ are grown by the Czochralski method from the melt. Continuous-wave laser operation with Ti:sapphire laser pumping is demonstrated at room temperature without special cooling. Tunability from 1017 to 1057 nm and from 1015 to 1053 nm is achieved for Yb:NaLa(WO 4 ) 2 and Yb:NaLa(MoO 4 ) 2 , respectively. A maximum output power of 205 mW is obtained with Yb:NaLa(WO 4 ) 2 . (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  16. Clarifying the link between von Neumann and thermodynamic entropies

    Science.gov (United States)

    Deville, Alain; Deville, Yannick

    2013-01-01

    The state of a quantum system being described by a density operator ρ, quantum statistical mechanics calls the quantity - kTr( ρln ρ), introduced by von Neumann, its von Neumann or statistical entropy. A 1999 Shenker's paper initiated a debate about its link with the entropy of phenomenological thermodynamics. Referring to Gibbs's and von Neumann's founding texts, we replace von Neumann's 1932 contribution in its historical context, after Gibbs's 1902 treatise and before the creation of the information entropy concept, which places boundaries into the debate. Reexamining von Neumann's reasoning, we stress that the part of his reasoning implied in the debate mainly uses thermodynamics, not quantum mechanics, and identify two implicit postulates. We thoroughly examine Shenker's and ensuing papers, insisting upon the presence of open thermodynamical subsystems, imposing us the use of the chemical potential concept. We briefly mention Landau's approach to the quantum entropy. On the whole, it is shown that von Neumann's viewpoint is right, and why Shenker's claim that von Neumann entropy "is not the quantum-mechanical correlate of thermodynamic entropy" can't be retained.

  17. Die Rolle von RANK-Ligand und Osteoprotegerin bei Osteoporose

    Directory of Open Access Journals (Sweden)

    Hofbauer LC

    2004-01-01

    Full Text Available Receptor activator of nuclear factor (NF- κB ligand (RANKL, sein zellulärer Rezeptor RANK und der Decoy-Rezeptor Osteoprotegerin (OPG stellen ein essentielles Zytokinsystem für die Zellbiologie von Osteoklasten dar. Verschiedene Untersuchungen belegen die Bedeutung von Störungen des OPG/RANKL/RANK-Systems bei der Pathogenese metabolischer Knochenerkrankungen. In dieser Arbeit werden die wichtigsten Störungen des OPG/RANKL/RANK-Systems bei verschiedenen Osteoporoseformen dargestellt. Östrogenrezeptor- (ER- Agonisten wie 17 β-Östradiol, Raloxifen und Genistein stimulieren die osteoblastäre Produktion von OPG durch Aktivierung von ER- α in vitro, während Lymphozyten von Patientinnen mit Östrogenmangel RANKL überexprimieren. Die parenterale Gabe von OPG vermag den mit Östrogenmangel assoziierten Knochenverlust im Tiermodell und in einer kleineren klinischen Studie zu verhindern. Glukokortikoide und Immunsuppressiva steigern gleichzeitig die RANKL-Expression und hemmen die OPG-Produktion in osteoblastären Zellen in vitro. Glukokortikoide sind auch in vivo imstande, die OPG-Serumspiegel deutlich zu reduzieren. Dagegen hemmen biomechanische Reize in vitro die RANKL-Produktion und steigern die OPG-Produktion. Ein Fehlen dieser biomechanischen Reize bei längerer Immobilisierung kann daher den RANKL/OPG-Quotienten steigern, während die tierexperimentelle Immobilisierungs-Osteoporose durch die parenterale Gabe von OPG gemildert werden kann.

  18. Synthesis and thermoelectric properties of rare earth Yb-doped Ba8−xYbxSi30Ga16 clathrates

    International Nuclear Information System (INIS)

    Liu, Lihua; Li, Feng; Wei, Yuping; Chen, Ning; Bi, Shanli; Qiu, Hongmei; Cao, Guohui; Li, Yang

    2014-01-01

    Highlights: • Samples with the chemical formula Ba8− x Yb x Si 30 Ga 16 (x = 0, 0.5, 0.7, 1 and 1.5) were prepared. • Some Yb atoms enter the clathrate lattice to replace Ba, while other Yb atoms are oxidized as Yb 2 O 3 . • The thermal conductivity decreases with Yb-doping. • Thermoelectric figure of merit ZT significantly increased. -- Abstract: The potential thermoelectric and magnetic application of clathrate materials with rare-earth doping is the focus of much of the recent research activity in the synthetic material physics and chemistry. A series of clathrate samples with the chemical formula Ba 8−x Yb x Si 30 Ga 16 (x = 0, 0.5, 0.7, 1 and 1.5) were prepared by combining arc melting, ball milling and spark plasma sintering (SPS) techniques. X-ray diffraction and scanning electronic microscopy combined with energy-dispersive X-ray spectroscopy (EDS) analysis showed the dominant phase to be the type-I clathrate. Whereas, X-ray structural refinement and EDS analysis indicated that some Yb atoms enter the clathrate lattice to replace Ba at 2a sites, while other Yb atoms are oxidized as Yb 2 O 3 precipitated around grain boundaries. The solid solubility of Yb into clathrate lattice yielded x ∼ 0.3. Comparative analysis between Yb-doped and Yb-free clathrates showed that the thermal conductivity decreases with Yb-doping. Consequently, thermoelectric figure of merit ZT significantly increased

  19. High slope efficiency and high refractive index change in direct-written Yb-doped waveguide lasers with depressed claddings.

    Science.gov (United States)

    Palmer, Guido; Gross, Simon; Fuerbach, Alexander; Lancaster, David G; Withford, Michael J

    2013-07-15

    We report the first Yb:ZBLAN and Yb:IOG10 waveguide lasers fabricated by the fs-laser direct-writing technique. Pulses from a Titanium-Sapphire laser oscillator with 5.1 MHz repetition rate were utilized to generate negative refractive index modifications in both glasses. Multiple modifications were aligned in a depressed cladding geometry to create a waveguide. For Yb:ZBLAN we demonstrate high laser slope efficiency of 84% with a maximum output power of 170 mW. By using Yb:IOG10 a laser performance of 25% slope efficiency and 72 mW output power was achieved and we measured a remarkably high refractive index change exceeding Δn = 2.3 × 10(-2).

  20. Emission characteristics of the Yb3+-sensitized Tm3+-doped optical fiber upon pumping with infrared LED

    International Nuclear Information System (INIS)

    Htein, Lin; Fan, Weiwei; Han, Won-Taek

    2014-01-01

    Near infrared emissions at 975, 1040 and 1450 nm of the Yb 3+ -sensitized Tm 3+ -doped optical fiber were obtained upon simultaneous excitation of Yb 3+ and Tm 3+ ions using the infrared LED. -- Highlights: • A novel pumping scheme for 1450 nm emission from 3 H 4 → 3 F 4 transition of Tm was demonstrated. • The absorption bands of Yb and Tm located within 690–970 nm were simultaneously excited with the IR LED. • Near infrared emissions at 975, 1040 and 1450 nm were obtained. • The Yb 3+ /Tm 3+ -codoped fiber showed the good spectroscopic quality and the increase of radiative lifetime of 3 H 4 level. • This LED pumping scheme can be useful for low-cost S-band fiber laser/amplifier applications

  1. Lattice dynamics and substrate-dependent transport properties of (In, Yb)-doped CoSb3 skutterudite thin films

    KAUST Repository

    Sarath Kumar, S. R.; Cha, Dong Kyu; Alshareef, Husam N.

    2011-01-01

    Lattice dynamics, low-temperature electrical transport, and high-temperature thermoelectric properties of (In, Yb)-doped CoSb3thin films on different substrates are reported. Pulsed laser deposition under optimized conditions yielded single

  2. Das Geschäftsmodell von Retail Banken im Wandel der Digitalisierung

    OpenAIRE

    Messikommer, Cédric

    2016-01-01

    Der Prozess der Digitalisierung führt in unterschiedlichen Branchen zu tiefgreifenden Veränderungen. Dazu gehört auch der Finanzsektor, dessen Umfeld von erodierenden Margen und Tiefstzinsen geprägt ist. Die Digitalisierung hat weitreichende Auswirkungen auf die Geschäftsmodelle von Banken und speziell von Retail Banken. Deren Basisdienstleistungen werden zunehmend von neuen Mitbewerbern mit modernster Internet-Technologie angeboten. Damit sind wesentliche Teile der Wertschöpfungskette von Re...

  3. Strukturbasierte Entwicklung von Assaysystemen und Charakterisierung von orthosterischen und allosterischen Kinaseinhibitoren

    OpenAIRE

    Klüter, Sabine

    2010-01-01

    Die Proteinkinasen stellen eine wichtige Enzymklasse für die Regulation der Signaltransduktion dar. Sie steuern diese diffizil regulierten, intrazellulären Signalkaskaden durch Übertragung der ?-Phosphatgruppe von ATP auf andere Proteine. Fehlregulationen dieser komplexen Stoffwechselwege können Krankheiten wie Krebs, Diabetes oder Autoimunkrankheiten verursachen. Somit gehören die Kinasen in den letzten Jahren zu den wichtigsten Zielproteinen der Pharmaindustrie. Die klassi...

  4. Der Effekt von Akupunktur in der Prävention von Prüfungsangst

    OpenAIRE

    Krüger, Peter

    2017-01-01

    Prüfungsangst ist ein weit verbreitetes gesellschaftliches Phänomen, das bisher in nur wenigen wissenschaftlichen Ansätzen untersucht wurde. Die Zahl der Studenten, die Gehirn - Doping zur Leistungssteigerung und zur Minimierung von Prüfungsangst nutzen, steigt stetig an. In bisherigen Studien wurde Akupunktur an Herz 7 als vielversprechende Behandlungsalternative dargestellt. Basierend auf diesen Ergebnissen, wurde in dieser Arbeit untersucht, ob eine Einzelpunktakupunktur an Herz 7 die ...

  5. Lifetime-broadening-suppressed X-ray absorption spectrum of β-YbAlB4 deduced from Yb 3d → 2p resonant X-ray emission spectroscopy

    International Nuclear Information System (INIS)

    Kawamura, Naomi; Mizumaki, Masaichiro; Kanai, Noriko; Hayashi, Hisashi; Matsuda, Yasuhiro H.; Kuga, Kentaro; Nakatsuji, Satoru; Watanabe, Shinji

    2017-01-01

    In this work, the Yb 3d → 2p (Yb Lα 1,2 ) resonant X-ray emission spectrum of β-YbAlB 4 was acquired using excitation energies around the Yb L 3 -edge, at 2 K. Subsequently, the lifetime-broadening-suppressed (LBS) X-ray absorption structure (XAS) spectrum was obtained using the SIM-RIXS program. This spectrum was found to exhibit clearly resolved pre-edge and shoulder structures. Resonant Lα 1 emission spectra were well reproduced from LBS-XAS profiles over wide ranges of excitation and emission energies. In contrast, noticeable discrepancies appeared between the experimental and simulated Lα 2 emission spectra, suggesting an effect resulting from M 4 M 5 O 1 Coster-Kronig transitions. LBS-XAS, in conjunction with partial fluorescence yield (PFY) XAS and transmission XAS, determined a value for the Yb valence (v) in β-YbAlB 4 of 2.76 ± 0.08 at 2 K. Despite this relatively large uncertainty in v, each method provided a consistent variation in valence (δv) as the temperature was raised from 2 to 280 K: 0.060 ± 0.004 (LBS-XAS), 0.061 ± 0.005 (PFY-XAS) and 0.058 ± 0.007 (transmission XAS). The smaller δv associated with LBS-XAS demonstrates the greater precision of this method. (author)

  6. [Albert Reder Ritter von Schellmann (1826-1904)].

    Science.gov (United States)

    Schmidt, G; Holubar, K

    1990-01-01

    Albert Reder von Schellmann (1826-1904) was an important syphilidologist of the Vienna Medical School in the second half of the nineteenth century. He went in for the dualistic concept of the origin of syphilis and ulcer caused by soft chancre. In 1870 - Reder became head of a third dermato-syphilidologic department in the "Josephinum" in Vienna, where military surgeons got their medical education. At the same time the two full professorships of dermatosyphilidology in the Vienna General Hospital were held by Ferdinand von Hebra (1816-1880) and Carl Ludwig Sigmund von Ilanor (1810-1883).

  7. Speziation von Gadolinium-MRT-Kontrastmitteln in Umweltmatrizes

    OpenAIRE

    Lindner, Uwe

    2017-01-01

    Gd-Kontrastmittel werden in der Medizin für die Magnetresonanztomographie (MRT) benötigt, um einen besseren Bildkontrast zu erzielen. Nach der Anwendung gelangen diese Arzneimittel über das Abwasser in die Klärwerke und von dort in die jeweiligen anliegenden Oberflächengewässer. Somit wird es notwendig, den Verbleib der Gd-MRT-Kontrastmittel in der Umwelt zu verfolgen und aufzuklären. In dieser Arbeit werden für die Analyse von Umweltproben Methoden zur Speziesanalytik von Gd-Kontrastmitteln ...

  8. Influence of O_2 exposure on the interaction between CH_4 and amorphous AlYB_1_4

    International Nuclear Information System (INIS)

    Hunold, Oliver; Wiesing, Martin; Arcos, Teresa de los; Music, Denis; Grundmeier, Guido; Schneider, Jochen M.

    2017-01-01

    Highlights: • Influence of O_2 exposure on the surface chemistry of a-AlYB_1_4 on the interaction with CH_4 and PE studied by ab initio and UHV-AFM. • Predicted stronger interaction is consistent with experimentally observed trends. • Upon O_2 exposure surface bonding becomes more semiconducting causing a charge redistribution within the adsorbed CH_4 molecule. • The data serve as proof of concept for exploring polymer − hard coating interactions in varying atmospheres. - Abstract: The influence of surface oxidation on the interaction between CH_4 and amorphous AlYB_1_4 (a-AlYB_1_4) has been studied theoretically by using density functional theory and experimentally by ultra-high vacuum atomic force microscopy (UHV-AFM). CH_4 mimics the –CH_3 termination and aliphatic subunits of a polymer chain. Low-energy ion scattering measurements of magnetron sputtered thin films suggest that the bonding at the surfaces of pristine a-AlYB_1_4 and O_2 exposed a-AlYB_1_4 (O_2//a-AlYB_1_4) is metal-boron and metal-oxygen dominated, respectively. Based on the ab initio calculations the adsorption energies of CH_4 on a-AlYB_1_4 and O_2//a-AlYB_1_4 decreases from −0.07 to −0.30 eV, respectively. This trend is consistent with experimental data obtained by colloidal probe UHV-AFM studies with a polyethylene sphere, where larger adhesion forces for the O_2 exposed surface as compared to the pristine a-AlYB_1_4 surface were measured. No charge transfer takes place between CH_4 and the pristine as well as the O_2 exposed a-AlYB_1_4. Oxygen chemisorption induces changes in surface bonding. States at the Fermi level are depleted upon oxidation, hence the surface bonding becomes more semiconducting causing a charge redistribution within the adsorbed CH_4 molecule. Hence, these data serve as proof of concept for exploring the effect of O_2 exposure on the interaction between aliphatic polymers and a-AlYB_1_4 using a correlative experimental and theoretical research approach.

  9. Optical properties of Mg2+, Yb3+, and Ho3+ tri-doped LiNbO3 crystals

    Science.gov (United States)

    Dai, Li; Liu, Chun-Rui; Tan, Chao; Yan, Zhe-Hua; Xu, Yu-Heng

    2017-04-01

    A series of LiNbO3 crystals tri-doped with Mg{}2+, Yb{}3+, and Ho{}3+ are grown by the conventional Czochraski technique. The concentrations of Mg{}2+, Yb{}3+, and Ho{}3+ ions in Mg:Yb:Ho:LiNbO3 crystals are measured by using an inductively coupled plasma atomic emission spectrometry. The x-ray diffraction is proposed to determine the lattice constant and analyze the internal structure of the crystal. The light-induced scattering of Mg:Yb:Ho:LiNbO3 crystal is quantitatively described via the threshold effect of incident exposure energy flux. The exposure energy ({E}{{r}}) is calculated to discuss the optical damage resistance ability. The exposure energy of Mg(7 mol):Yb:Ho:LiNbO3 crystal is 709.17 J/cm2, approximately 425 times higher than that of the Mg(1 mol):Yb:Ho:LiNbO3 crystal in magnitude. The blue, red, and very intense green bands of Mg:Yb:Ho:LiNbO3 crystal are observed under the 980-nm laser excitation to evaluate the up-conversion emission properties. The dependence of the emission intensity on pumping power indicates that the up-conversion emission is a two-photon process. The up-conversion emission mechanism is discussed in detail. This study indicates that Mg:Yb:Ho:LiNbO3 crystal can be applied to the fabrication of new multifunctional photoluminescence devices. Project supported by the National Natural Science Foundation of China (Grant No. 51301055), the Youth Science Fund of Heilongjiang Province, China (Grant No. QC2015061), the Special Funds of Harbin Innovation Talents in Science and Technology Research, China (Grant No. 2015RQQXJ045 ), and the Science Funds for the Young Innovative Talents of Harbin University of Science and Technology, China (Grant No. 201501).

  10. Intrinsic Bistability and Critical Slowing in Tm3+/Yb3+ Codoped Laser Crystal with the Photon Avalanche Mechanism

    International Nuclear Information System (INIS)

    Li, Li; Li-Xue, Chen; Xin-Lu, Zhang

    2009-01-01

    We present theoretically a novel intrinsic optical bistability (IOB) in the Tm 3+ /Yb 3+ codoped system with a photon avalanche mechanism. Numerical simulations based on the rate equation model demonstrate distinct IOB hysteresis and critical slowing dynamics around the avalanche thresholds. Such an IOB characteristic in Tm 3+ /Yb 3+ codoped crystal has potential applications in solid-state bistable optical displays and luminescence switchers in visible-infrared spectra. (fundamental areas of phenomenology (including applications))

  11. Modernisation of ventilation systems; Modernisierung von Lueftungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Richter, W. [Technische Univ. Dresden (Germany). Inst. fuer Thermodynamik und Technische Gebaeudeausruestung

    1997-12-31

    When redeveloping buildings it is common to use window constructions with air-tight rabbets which obviate the inflow of fresh air almost entirely. This leads to the well-known structural-physics and hygienic consequences. As an added effect, the distinctly enhanced thermal insulation results in changes in dynamic heat loss. The paper focuses on the issues of how to safeguard the inflow of fresh air, and the heating capacity of radiators. (MSK) [Deutsch] Da die bei Gebaeudesanierungen eingesetzten fugendichten Fensterkonstruktionen die Nachstroemmoeglichkeiten fuer die Zuluft fast ganz unterbinden, fuehrt das zu den bekannten bauphysikalischen und hygienischen Konsequenzen. Dazu kommen veraenderte dynamische Waermverlustverhaeltnisse aufgrund der deutlich verbesserten Waermedaemmung. Im Folgenden wird schwerpunktmaessig auf die Probleme Zuluftsicherung und Waermeleistung von Heizkoerpern eingegangen.

  12. Of von Willebrand factor and platelets.

    Science.gov (United States)

    Bryckaert, Marijke; Rosa, Jean-Philippe; Denis, Cécile V; Lenting, Peter J

    2015-01-01

    Hemostasis and pathological thrombus formation are dynamic processes that require multiple adhesive receptor-ligand interactions, with blood platelets at the heart of such events. Many studies have contributed to shed light on the importance of von Willebrand factor (VWF) interaction with its platelet receptors, glycoprotein (GP) Ib-IX-V and αIIbβ3 integrin, in promoting primary platelet adhesion and aggregation following vessel injury. This review will recapitulate our current knowledge on the subject from the rheological aspect to the spatio-temporal development of thrombus formation. We will also discuss the signaling events generated by VWF/GPIb-IX-V interaction, leading to platelet activation. Additionally, we will review the growing body of evidence gathered from the recent development of pathological mouse models suggesting that VWF binding to GPIb-IX-V is a promising target in arterial and venous pathological thrombosis. Finally, the pathological aspects of VWF and its impact on platelets will be addressed.

  13. Ex-ante Evaluation von Investitionsalternativen

    Directory of Open Access Journals (Sweden)

    Matthias Müller

    2017-12-01

    Full Text Available Der Beitrag zeigt, wie mit Hilfe der Methode der agentenbasierten Modellierung und Simulation (ABMS ein Beitrag zur ex-ante Policy-Beratung geleistet werden kann. Anhand eines exemplarischen Anwendungsfalls, der VISIBLE Simulationsumgebung („Virtual Simulation Lab for the Analysis of Investments in Learning and Education“, diskutieren wir die Konsequenzen unterschiedlicher Kooperationsförderinstrumente für Wissensdiffusionsprozesse in Netzwerken am Beispiel der Region Heilbronn-Franken. Die Simulationsergebnisse zeigen, dass die strukturelle Konfiguration eines regionalen Innovationssystems eine zentrale Bedeutung für die Gestaltung von Kooperationsfördermaßnahmen hat und dass Interventionen, die darauf abzielen, Wissenstransfer zwischen den Akteuren anzuregen, genau die entgegengesetzten Wirkungen entfalten können.

  14. Budke, Alexandra; Kanwischer, Detlef; Pott, Andreas (Hg.), Internetgeographien : Beobachtungen zum Verhältnis von Internet, Raum und Gesellschaft / [rezensiert von] Helmut Klüter

    OpenAIRE

    Klüter, Helmut

    2009-01-01

    Rezensiertes Werk: Internetgeographien : Beobachtungen zum Verhältnis von Internet, Raum und Gesellschaft / hrsg. von Alexandra Budke ... - Stuttgart : Steiner, 2004. - 192 S. : Ill., graph. Darst., Kt. - (Erdkundliches Wissen ; 136) ISBN 3-515-08506-8

  15. Continuous wave and tunable laser operation of Yb3+ in disordered NaLa(MoO4)2

    Science.gov (United States)

    Rico, M.; Liu, J.; Cano-Torres, J. M.; García-Cortés, A.; Cascales, C.; Zaldo, C.; Griebner, U.; Petrov, V.

    2005-09-01

    Continuous-wave Yb3+ laser operation is studied in single crystals of disordered NaLa(MoO4)2 at room temperature. The sample used was grown by the Czochralski technique and incorporates an Yb ion density of 3.1×1020 cm-3. The effect of the Yb concentration on some of the crystal properties is described as well as the spectroscopic Yb3+ properties at 5 K. Maximum slope efficiencies of about 40% for π and 38% for σ polarization were obtained under Ti:sapphire laser pumping near 976 nm, respectively. The maximum output power for the π polarization was 400 mW at 1039.5 nm, the threshold in this case amounted to 240 mW (absorbed pump power). The laser emission was tunable between 1016 and 1064 nm with a Lyot filter. Lasing was also realized by pumping with a fiber-coupled diode laser module. Maximum output power of 900 mW at 1035 nm was achieved in this case for the π polarization and the threshold was 280 mW. The results, in terms of output power and tunability, are superior in comparison to all previous reports on Yb-doped disordered double tungstate or molybdate crystals and represent a significant improvement in comparison to earlier experiments with low-doped Yb:NaLa(MoO4)2.

  16. Identification of YB-1 as a regulator of PTP1B expression: implications for regulation of insulin and cytokine signaling

    Science.gov (United States)

    Fukada, Toshiyuki; Tonks, Nicholas K.

    2003-01-01

    Changes in expression of PTP1B, the prototypic protein tyrosine phosphatase, have been associated with various human diseases; however, the mechanisms by which PTP1B expression is regulated have not been defined. We have identified an enhancer sequence within the PTP1B promoter which serves as a binding site for the transcription factor Y box-binding protein-1 (YB-1). Overexpression of YB-1 resulted in increased levels of PTP1B. Furthermore, depletion of YB-1 protein, by expression of a specific antisense construct, led to an ∼70% decrease in expression of PTP1B, but no change in the level of its closest relative, TC-PTP. Expression of antisense YB-1 resulted in increased sensitivity to insulin and enhanced signaling through the cytokine receptor gp130, which was suppressed by re-expression of PTP1B. Finally, we observed a correlation between the expression of PTP1B and that of YB-1 in cancer cell lines and an animal model of type II diabetes. Our data reveal an important role for YB-1 as a regulator of PTP1B expression, and further highlight PTP1B as a critical regulator of insulin- and cytokine-mediated signal transduction. PMID:12554649

  17. Transport and magnetic properties of new heavy-fermion antiferromagnet YbNi{sub 3}Al{sub 9}

    Energy Technology Data Exchange (ETDEWEB)

    Ohara, S; Yamashita, T; Mori, Y; Sakamoto, I, E-mail: ohara.shigeo@nitech.ac.jp [Department of Engineering Physics, Electronics and Mechanics, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya 466-8555 (Japan)

    2011-01-01

    We have synthesized a new Yb-based Kondo-lattice compound YbNi{sub 3}Al{sub 9}. This compound crystallizes in a trigonal ErNi{sub 3}Al{sub 9}-type structure (space group R32), in which the Yb-ion is arranged in a two-dimensional honey-comb lattice perpendicular to the c-axis. We report the first measurements of electrical resistivity and magnetization for single-crystalline samples of YbNi{sub 3}Al{sub 9}. The electrical resistivity of YbNi{sub 3}Al{sub 9} is characteristic of the typical properties of heavy-fermion antiferromagnets with a Neel temperature of T{sub N} = 3.4 K. The transport and magnetic properties exhibit large anisotropy in the low-temperature region owing to an interplay among the crystalline-electric-field effect, the Ruderman-Kittel-Kasuya-Yoshida interaction, and the Kondo effect. Below T{sub N}, the metamagnetic transition is observed at a very low magnetic field of around 1 kOe with the field applied along the a-axis. The magnetic structure of YbNi{sub 3}Al{sub 9} is highly sensitive to the applied magnetic field.

  18. Synthesis, Structural Characterization and Up-Conversion Luminescence Properties of NaYF4:Er3+,Yb3+@MOFs Nanocomposites

    Science.gov (United States)

    Giang, Lam Thi Kieu; Marciniak, Lukasz; Huy, Tran Quang; Vu, Nguyen; Le, Ngo Thi Hong; Binh, Nguyen Thanh; Lam, Tran Dai; Minh, Le Quoc

    2017-10-01

    This paper describes a facile synthesis of NaYF4:Er3+,Yb3+ nanoparticles embraced in metal-organic frameworks (MOFs), known as NaYF4:Er3+, Yb3+@MOFs core/shell nanostructures, by using iron(III) carboxylate (MIL-100) and zeolitic imidazolate frameworks (ZIF-8). Morphological, structural and optical characterization of these nanostructures were investigated by field emission-scanning electron microscopy, Fourier transform infrared spectroscopy, x-ray diffraction, and up-conversion luminescence measurements. Results showed that spherical-shaped NaYF4:Er3+,Yb3+@MIL-100 nanocomposites with diameters of 150-250 nm, and rod-shaped NaYF4:Er3+,Yb3+@ZIF-8 nanocomposites with lengths of 300-550 nm, were successfully synthesized. Under a 980-nm laser excitation at room temperature, the NaYF4:Er3+,Yb3+@MOFs nanocomposites exhibited strong up-conversion luminescence with two emission bands in the green part of spectrum at 520 nm and 540 nm corresponding to the 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions of Er3+ ions, respectively, and a red emission band at 655 nm corresponding to the 4F9/2 → 4I15/2 transition of Er3+ ions. The above properties of NaYF4:Er3+,Yb3+@MOFs make them promising candidates for applications in biotechnology.

  19. Photoluminescence study of Sm{sup 3+}–Yb{sup 3+}co-doped tellurite glass embedding silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Reza Dousti, M., E-mail: mrdousti@ifsc.usp.br [Laboratório de Espectroscopia de Materiais Funcionais (LEMAF), Instituto de Fisica de São Carlos, Universidade de São Paulo, Av. Trabalhador So-carlense 400, São Carlos, SP 13566-590 (Brazil); Department of Physics, Tehran-North Branch, Islamic Azad University Tehran (Iran, Islamic Republic of); Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, Skudai 81310, Johor (Malaysia); Amjad, R.J. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, Skudai 81310, Johor (Malaysia); Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Hosseinian S, R.; Salehi, M.; Sahar, M.R. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, Skudai 81310, Johor (Malaysia)

    2015-03-15

    We report on the upconversion emission of Sm{sup 3+} ions doped tellurite glass in the presence of Yb{sup 3+} ions and silver nanoparticles. The enhancement of infrared-to-visible upconversion emissions is achieved under 980 nm excitation wavelength and attributed to the high absorption cross section of Yb{sup 3+} ions and an efficient energy transfer to Sm{sup 3+} ions. Further enhancements are attributed to the plasmonic effect via metallic nanoparticles resulting in the large localized field around rare earth ions. However, under excitation at 406 nm, the addition of Yb{sup 3+} content and heat-treated silver nanoparticles quench the luminescence of Sm{sup 3+} ions likely due to quantum cutting and plasmonic diluent effects, respectively. - Highlights: • Sm{sup 3+} tellurite glasses co-doped with Yb{sup 3+} ions and tri-doped with Yb{sup 3+}:Ag NPs were prepared. • In first step, Yb{sup 3+} ions enhanced the upconversion emissions of Sm{sup 3+} doped samples. • In second step, Ag NPs further enhanced the upconversion emissions in tri-doped glasses. • Finally, the quench in luminescence under 406 nm excitation is observed and discussed.

  20. Ytterbium silicide (YbSi{sub 2}). A promising thermoelectric material with a high power factor at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Tanusilp, Sora-at; Ohishi, Yuji; Muta, Hiroaki [Graduate School of Engineering, Osaka University, Suita, Osaka (Japan); Yamanaka, Shinsuke [Graduate School of Engineering, Osaka University, Suita, Osaka (Japan); Research Institute of Nuclear Engineering, University of Fukui, Tsuruga (Japan); Nishide, Akinori [Graduate School of Engineering, Osaka University, Suita, Osaka (Japan); Center for Exploratory Research, Research and Development Group, Hitachi, Ltd., Kokubunji, Tokyo (Japan); Hayakawa, Jun [Center for Exploratory Research, Research and Development Group, Hitachi, Ltd., Kokubunji, Tokyo (Japan); Kurosaki, Ken [Graduate School of Engineering, Osaka University, Suita, Osaka (Japan); Research Institute of Nuclear Engineering, University of Fukui, Tsuruga (Japan); JST, PRESTO, Kawaguchi, Saitama (Japan)

    2018-02-15

    Metal silicide-based thermoelectric (TE) materials have attracted attention in the past two decades, because they are less toxic, with low production cost and high chemical stability. Here, we study the TE properties of ytterbium silicide YbSi{sub 2} with a specific layered structure and the mixed valence state of Yb{sup 2+} and Yb{sup 3+}. YbSi{sub 2} exhibits large Seebeck coefficient, S, accompanied by high electrical conductivity, σ, leading to high power factor, S{sup 2}σ, of 2.2 mW m{sup -1} K{sup -2} at room temperature, which is comparable to those of state-of-the-art TE materials such as Bi{sub 2}Te{sub 3} and PbTe. Moreover, YbSi{sub 2} exhibits high Grueneisen parameter of 1.57, which leads to relatively low lattice thermal conductivity, κ{sub lat}, of 3.0 W m{sup -1} K{sup -1} at room temperature. The present study reveals that YbSi{sub 2} can be a good candidate of TE materials working near room temperature. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Effect of substituted rare earth element in (Yb1-xNd x)Ba2Cu3O y thin film on growth orientation and superconducting properties

    International Nuclear Information System (INIS)

    Honda, R.; Ichino, Y.; Yoshida, Y.; Takai, Y.; Matsumoto, K.; Ichinose, A.; Kita, R.; Mukaida, M.; Horii, S.

    2005-01-01

    We studied the orientation and superconducting properties in (Yb 1-x Nd x )Ba 2 Cu 3 O y (Yb/Nd123) thin films as a function of Yb/Nd composition ratio x. As a results, we needed so high oxygen pressure as to increase x for obtaining the c-axis oriented films. J c -B curves in the Yb/Nd123 thin films were superior to that in YBa 2 Cu 3 O y thin film. Since a RE fluctuation in a composition in the Yb/Nd123 thin films was observed with TEM-EDX, we speculated the pinning centers in the Yb/Nd123 thin films were strongly affected by the RE fluctuation

  2. Entwicklung der Reglementierung von 10 MEM-Berufen im Kontext von Bildungsreformen und dem Wandel in der Arbeitswelt: Eine Kurzstudie im Auftrag von LIBS: Eine Kurzstudie im Auftrag von LIBS Industrielle Berufslehren Schweiz, Baden

    OpenAIRE

    Egg, Maria Esther; Renold, Ursula

    2015-01-01

    Im Auftrag der LIBS Industrielle Berufslehren Schweiz, hat die KOF die Entwicklung von 10 MEM1-Berufsbildern seit dem ersten Berufsbildungsgesetz dargestellt und diese eingebettet in eine kurze Zusammenfassung der wichtigsten Etappenschritte des Schweizer Berufsbildungssystems.

  3. Magnus Georg von Paucker (1787-1855) / Eckhard Spring

    Index Scriptorium Estoniae

    Spring, Eckhard

    2013-01-01

    Eestis sündinud ja Tartu Ülikoolis õppinud silmapaistvast baltisaksa teadlasest ja tema lapselapsest Alexandrine Pauckerist. 23. novembril 2012 Jelgavas/Mitaus toimunud Magnus Georg von Pauckerile pühendatud teaduskonverentsist

  4. Warum das Controlling den systematischen Einsatz von Simulationen vorantreiben sollte

    DEFF Research Database (Denmark)

    Spitzner, Jan; Schneider, Melanie L.

    2017-01-01

    Simulationen werden in der Unternehmenssteuerung heutzutage noch nicht systematisch eingesetzt. Dass sich jedoch die existierenden Hemmnisse durchaus überwinden lassen, legen die Antworten von Studienteilnehmern nahe, die Simulationen häufig einsetzen. Dabei kann Controlling eine Vorreiterrolle e...

  5. Pharmakobotanische Untersuchungen von Lavendelsorten auf dem Plattensee- Plateau

    Directory of Open Access Journals (Sweden)

    Tóth, Frida

    2014-09-01

    Full Text Available Auf dem Hof Dörgicsei Levendula Major GmbH wurden 9 Lavendelsorten (6 Sorten von Lavandula angustifolia und 3 Sorten von Lavandula x intermedia untersucht. Neben den morphologischen und Wachstumseigenschaften wurden auch Frisch- und Trockengewichte bewertet. Quantitative und qualitative Untersuchungen von den Blüten- und Ätherischöldrogen wurden auch durchgeführt. Die statistische Analyse zeigte signifikant höhere Erträge bei den Sorten L. angustifolia ’Essence Purple’ und L. x intermedia ’Edelweiss’. Gehalt und Zusammensetzung von ätherischem Öl war eindeutig bei der Sorte L. angustifolia ’Ellagance Purple’ am günstigsten.

  6. Pure Jauch-Piron states on von Neumann algebras

    International Nuclear Information System (INIS)

    Hamhalter, J.

    1993-01-01

    We study Jauch-Piron states and two-valued measures on von Neumann algebra. We prove as the main result that, under some set-theoretical assumption, a pure state of a von Neumann algebra A not containing a central abelian portion is Jauch-Piron if and only if it is σ-additive. Moreover, we show that this result holds for type I factor indenpendently on the set-theoretical axiomatics. As a consequence we obtain a lucid characterization of pure Jauch-Piron states on von Neumann algebras acting on a Hilbert space with real-nonmeasurable dimension (this can be viewed as a generalization of the paper). We also characterize the von Neumann algebras whose logic of projections is Jauch-Piron. Finally, we prove that every two-valued measure on the projection logic of A, where A contains no type I 2 central portion, has to be concentrated at an abelian direct summand of A. (orig.)

  7. Von Krahli Teater toob Eestisse erakordse auhinna / Tiit Tuumalu

    Index Scriptorium Estoniae

    Tuumalu, Tiit, 1971-

    2004-01-01

    Bessie-auhinna puhul, millega New Yorgis pärjati Von Krahli Teatri lavastust "Luikede järv." Mõjukuselt on seda võrreldud Broadway teatriauhinna Tonyga. Lisatud lühiandmed P. Jalaka ja S. Pepeljajevi kohta

  8. Frobenius theory for positive maps of von Neumann algebras

    International Nuclear Information System (INIS)

    Albeverio, S.; Hoegh-Krohn, R.

    1978-01-01

    Frobenius theory about the cyclic structure of eigenvalues of irreducible non negative matrices is extended to the case of positive linear maps of von Neumann algebras. Semigroups of such maps and ergodic properties are also considered. (orig.) [de

  9. Frustrated magnetism in Yb{sub 2}Fe{sub 12}P{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Grube, Kai; Zocco, Diego A.; Weber, Frank; Kuntz, Sebastian; Loehneysen, Hilbert von [Karlsruhe Institute of Technology, Institut fuer Festkoerperphysik, 76021 Karlsruhe (Germany); Baumbach, Ryan [National High Magnetic Field Laboratory, Tallahassee (United States); Hamlin, James [Departement of Physics, University of Florida, Gainesville (United States); Lum, Ivy; Maple, M. Brian [Department of Physics, University of California, San Diego (United States); Lynn, Jeff; Huang, Qingzhen [NIST Center for Neutron Research, Gaithersburg (United States); Janoschek, Marc [Los Alamos National Laboratory (United States)

    2016-07-01

    Yb{sub 2}Fe{sub 12}P{sub 7} is characterized by a low magnetic transition temperature of T{sub N} ∼1 K and the breakdown of Fermi-liquid behavior. These properties suggest the proximity to a quantum critical point (QCP). The non-Fermi-liquid (NFL) behavior, however, does not conform to the standard QCP scenario described by the Hertz-Millis-Moriya theory. We measured thermal expansion, magnetostriction and magnetization. The pressure dependence was studied up to 15 GPa using resistivity measurements in piston cylinder and diamond anvil cells. The measurements reveal that only a small fraction of the Yb moments participate in the long-range magnetic order. The Grueneisen ratio does not diverge for T → 0 indicating that the NFL behavior is not related to a nearby pressure-induced QCP. In view of the unusual noncentrometric crystal structure, our observations might point to geometric frustration of the magnetic moments.

  10. Glomerular filtration in kidney recipients measured by plasma clearance of 169Yb-DTPA

    International Nuclear Information System (INIS)

    Stribrna, J.; Oppelt, A.; Jirickova, E.; Janata, V.; Kocandrle, V.; Sup, I.; Woller, P.; Franke, W.G.

    1986-01-01

    Values of 169 Yb-DTPA clearance (C DTPA ) calculated after a single injection were compared in 26 recipients of kidneys with renal clearance of inulin (C in ), polyfructosan S (C pf ) and creatinine (C cr ). In 21 patients the examinations were made simultaneously, in 5 patients C DTPA was measured within a short interval after the examination of renal clearance. The mean C DTPA values did not significantly differ from C cr but were significantly higher (p in and C pf (by 33% on average). Investigation of changes in C DTPA as compared with C in and C pf showed no significant difference in glomerular filtration (GF). This was measured using inulin and polyfructosan. The results showed that the differing molecular weight of inulin and polyfructosan S had no detectable effect on the GF of kidney recipients. The plasma clearance of 169 Yb-DTPA similarly to C cr overestimates the GF measured by inulin and polyfructosan clearance. (author)

  11. Resonant photoemission of La and Yb at the 3d absorption edge

    CERN Document Server

    Lagarde, P; Ogasawara, H; Kotani, A

    2003-01-01

    Resonant photoemission and resonant Auger experiments at the 3d threshold are presented for La and Yb over a binding energy domain which extends up to the 4p levels. These experimental results are well explained by calculations in the framework of full-multiplet Hartree-Fock theory with an atomic model. Strong participator and spectator Auger transitions are observed without ordinary Auger transition, indicating that the 4f wavefunction is well localized in the intermediate state even in the case of La. The 4d sub 3 sub / sub 2 and 4d sub 5 sub / sub 2 branching ratio of the 4d resonant photoemission of La at the M sub 4 and M sub 5 edges is observed experimentally and analyzed theoretically. The difference in the resonant processes behavior for La and Yb is discussed based upon the different 4f occupation number.

  12. Near infrared and upconversion luminescence behaviour of Er3+/Yb3+ codoped boro-tellurite glasses

    Science.gov (United States)

    Maheshvaran, K.; Arunkumar, S.; Vijayakumar, R.; Marimuthu, K.

    2014-04-01

    The broadband NIR and upconversion luminescence behavior in a new series of Er3+/Yb3+ codoped TeO2-B2O3-SrO-BaO-Li2O-LiF glasses have been studied exciting at a wavelength of 980 nm using semiconductor laser. A broadband emission is observed from 1450 to 1650 nm with a full width at half maximum (FWHM) around 165 nm in 0.5wt% Yb3+ ion content E0.5YLTB glass. The radiative parameters such as transition probability (A), stimulated emission cross-section (σE), experimental and calculated branching ratios (βR), optical gain width (σp×FWHM) and radiative lifetime (τcal) have been calculated for the 4I13/2→4I15/2 NIR emission. Upconversion luminescence spectra of the prepared glasses have been studied and the ESA & ET processes have also been discussed and reported.

  13. Diode-pumped Kerr-lens mode-locked femtosecond Yb:YAG ceramic laser

    Science.gov (United States)

    Zi-Ye, Gao; Jiang-Feng, Zhu; Ke, Wang; Jun-Li, Wang; Zhao-Hua, Wang; Zhi-Yi, Wei

    2016-02-01

    We experimentally demonstrated a diode-pumped Kerr-lens mode-locked femtosecond laser based on an Yb:YAG ceramic. Stable laser pulses with 97-fs duration, 2.8-nJ pulse energy, and 320-mW average power were obtained. The femtosecond oscillator operated at a central wavelength of 1049 nm and a repetition rate of 115 MHz. To the best of our knowledge, this is the first demonstration of a Kerr-lens mode-locked operation in a diode-pumped Yb:YAG ceramic laser with sub-100 fs pulse duration. Project supported by the National Major Scientific Instrument Development Project of China (Grant No. 2012YQ120047), the National Natural Science Foundation of China (Grant No. 61205130), and the Fundamental Research Funds for the Central Universities, China (Grant No. JB140502).

  14. Local probe (170Yb3+) measurements of magnetic fields in YBa2Cu3Ox

    International Nuclear Information System (INIS)

    Hodges, J.A.; Bonville, P.; Vincent, E.

    1989-01-01

    We introduce the technique of studying the field dependence of the electro-nuclear energy levels of a rare earth to measure the magnetic field present at the rare earth/yttrium site in YBa 2 Cu 3 O x . Measurements were made by 170 Yb spectroscopy. The hyperfine spectrum of the ground state Kramers doublet for Yb 3+ ions diluted into this matrix is sensitive to fields in the range 100 to 2000G. Flux penetration and trapping at the local site level have been measured in superconducting samples. A molecular field exists on the rare earth site in non superconducting samples suggesting that the ordered Cu2 magnetic moments are intrinsically non colinear

  15. Study of upconversion fluorescence property of novel Er3+/Yb3+ co-doped tellurite glasses.

    Science.gov (United States)

    Xu, Tie-Feng; Li, Guang-Po; Nie, Qiu-Hua; Shen, Xiang

    2006-06-01

    Er3+/Yb3+ co-doped TeO2-B2O3-Nb2O5-ZnO (TBN) glasses were prepared. The absorption spectra and upconversion luminescence spectra of TBN glasses were measured and analyzed. The upconversion emission bands centered at 530, 546 and 658 nm were observed under the excitation at 975 nm, corresponding to the transitions of 2H11/2-->4I15/2, 4S3/2-->4I15/2 and 4F9/2-->4I15/2 respectively. The ratio of red emission to green emission increases with an increasing of Yb3+ ions concentration. According to the quadratic dependence on excitation power, the possible upconversion mechanisms and processes were discussed.

  16. Systematic evaluation of a 171Yb optical clock by synchronous comparison between two lattice systems.

    Science.gov (United States)

    Gao, Qi; Zhou, Min; Han, Chengyin; Li, Shangyan; Zhang, Shuang; Yao, Yuan; Li, Bo; Qiao, Hao; Ai, Di; Lou, Ge; Zhang, Mengya; Jiang, Yanyi; Bi, Zhiyi; Ma, Longsheng; Xu, Xinye

    2018-05-22

    Optical clocks are the most precise measurement devices. Here we experimentally characterize one such clock based on the 1 S 0 - 3 P 0 transition of neutral 171 Yb atoms confined in an optical lattice. Given that the systematic evaluation using an interleaved stabilization scheme is unable to avoid noise from the clock laser, synchronous comparisons against a second 171 Yb lattice system were implemented to accelerate the evaluation. The fractional instability of one clock falls below 4 × 10 -17 after an averaging over a time of 5,000 seconds. The systematic frequency shifts were corrected with a total uncertainty of 1.7 × 10 -16 . The lattice polarizability shift currently contributes the largest source. This work paves the way to measuring the absolute clock transition frequency relative to the primary Cs standard or against the International System of Units (SI) second.

  17. Microscopic analysis of wobbling excitations in 156Dy and 162Yb

    International Nuclear Information System (INIS)

    Nazmitdinov, R. G.; Kvasil, J.

    2007-01-01

    In the cranked Nilsson-plus-random-phase approximation, we study low-lying quadrupole excitations of positive parity and negative signature in 156 Dy and 162 Yb at high spins. Special attention is paid to a consistent description of wobbling excitations and their identification among excited states. A good agreement between the available experimental data and the results of calculations is obtained. We find that the lowest odd-spin γ-vibrational states in 156 Dy transform into wobbling excitations after the backbending associated with the transition from an axially symmetric shape to a nonaxial shape. Similar results are predicted for 162 Yb. The analysis of electromagnetic transitions uniquely determines the sign of the γ deformation in both nuclei after the transition point

  18. Nanosecond Q-switched operation of coupled Yb and Tm fibre lasers

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Yuen H [Laser Photonics Research Group, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Qamar, Fadi [Laser Photonics Research Group, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); King, Terence A [Laser Photonics Research Group, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Ko, Do-Kyeong [Advanced Photonics Research Institute, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-Gu, Gwangju 500-712 (Korea, Republic of); Lee, Jongmin [Advanced Photonics Research Institute, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-Gu, Gwangju 500-712 (Korea, Republic of)

    2005-05-07

    A small scale coupled Yb-silica and Tm-silica fibre laser system is described with output at 1.9 {mu}m and with Q-switching using an acousto-optic modulator and also by mechanical optical modulation. The Yb-fibre laser pump source exhibited strong self-pulsation with high-intensity pulses due to stimulated Brillouin scattering. But regular Q-switched pulses were generated from the Tm-fibre laser with an energy of {approx}2.4 {mu}J and duration (FWHM) of {approx}280 ns for modulation frequencies of 1-20 kHz when using acousto-optic modulation. The main effects that limit the Q-switched pulse peak power are the onset of gain-switched pulsing during the low-Q state and strong pump excited state absorption.

  19. Upconversion luminescence properties of Y2O3:Yb3+, Er3+ nanostructures

    International Nuclear Information System (INIS)

    De Gejihu; Qin Weiping; Zhang Jishen; Zhang Jishuang; Wang, Yan; Cao Chunyan; Cui Yang

    2006-01-01

    Cubic Y 2 O 3 nanostructures doped with Yb 3+ and Er 3+ ions were synthesized by a facile hydrothermal method. Three distinct shapes such as nanotubes, nanospheres and nanoflakes formed in the products by adjusting the pH value of reacting solution. Powder X-ray diffraction analyses indicate that all the three nanostructures are pure cubic phase, while electron microscopy measurements confirm the formation of different morphologies. These nanostructures exhibit strong visible upconversion luminescence under the excitation of a 978-nm diode laser. In Yb 3+ - and Er 3+ - codoped Y 2 O 3 nanocrystals, the relative intensity of green emission became stronger as the size and morphology of sample changed from tubes to flakes

  20. Magnetic behavior of the nanophase of YbNi2 alloys

    Science.gov (United States)

    Ivanshin, V. A.; Gataullin, E. M.; Sukhanov, A. A.; Ivanshin, N. A.; Rojas, D. P.; Fernández Barquín, L.

    2017-04-01

    Variations in magnetic properties of the heavy-fermion YbNi2 alloy when milled in a high energy ball milling system have been investigated. The ferromagnetic transition ( T C = 10.4 K) in the initial sample almost vanishes after milling, which leads to the appearance of a magnetic transition at T* = 3.2 K in nanocrystallites. Before milling, processes of spin-lattice relaxation of the Orbach-Aminov type with the participation of the first excited Stark sublevel of the Yb3+ ion located at 75 K are dominating in the electron spin dynamics in the paramagnetic phase of the alloy. A comparative study of the temperature dependence of the magnetic properties and spectra of electron paramagnetic resonance in poly- and nanocrystalline samples indicates the existence of a magnetic inhomogeneity of the compound arising upon milling.

  1. Electronic structure and magnetic ordering of the unconventional antiferromagnet Yb3Pt4

    KAUST Repository

    Schwingenschlögl, Udo

    2009-12-01

    Applying density functional theory within the generalized gradient approximation, we investigate the electronic and magnetic properties of the intermetallic rare-earth system Yb3Pt4. This material recently has been put forward as host for quantum criticality, while details of the magnetic ordering could not be established (Bennett N. C.et al., J. Magn. & Magn. Mater., 321 (2009) 2021). In this context, we investigate the effect of spin-orbit coupling and compare various spin patterns from the energetic point of view, which enables us to determine the electronic ground state of Yb3Pt4. The assumption of an elementary superexchange mechanism yields a magnetic-coupling constant in good agreement with the experimental ordering temperature. Copyright © 2009 EPLA.

  2. Electronic structure and magnetic ordering of the unconventional antiferromagnet Yb3Pt4

    KAUST Repository

    Schwingenschlö gl, Udo; Gó mez, Javier Alexandra M; Grau-Crespo, Ricardo

    2009-01-01

    Applying density functional theory within the generalized gradient approximation, we investigate the electronic and magnetic properties of the intermetallic rare-earth system Yb3Pt4. This material recently has been put forward as host for quantum criticality, while details of the magnetic ordering could not be established (Bennett N. C.et al., J. Magn. & Magn. Mater., 321 (2009) 2021). In this context, we investigate the effect of spin-orbit coupling and compare various spin patterns from the energetic point of view, which enables us to determine the electronic ground state of Yb3Pt4. The assumption of an elementary superexchange mechanism yields a magnetic-coupling constant in good agreement with the experimental ordering temperature. Copyright © 2009 EPLA.

  3. Sympathetic cooling of ytterbium with rubidium; Sympathetische Kuehlung von Ytterbium mit Rubidium

    Energy Technology Data Exchange (ETDEWEB)

    Tassy, S.

    2007-12-14

    Within the scope of this thesis, a mixture of ultracold ytterbium and rubidium atoms was experimentally realized and investigated. For these experiments, a novel trap geometry was developed which allows simultaneous trapping and cooling of diamagnetic and paramagnetic atomic species. The main focus was put on the investigation of the interspecies scattering properties, where sympathetic cooling of ytterbium through elastic collisions with rubidium could be demonstrated. In addition, the interspecies scattering length could be determined. In the current configuration the combined trap allows the preparation of up to 2.10{sup 5} atoms of {sup 170}Yb, {sup 171}Yb, {sup 172}Yb, {sup 174}Yb or {sup 176}Yb at a temperature of 40..60 {mu}K and a density in the range of 10{sup 12} cm{sup -3}, and of about 10{sup 7} {sup 87}Rb atoms at a temperature of 25 {mu}K and a density in the range of 5.10{sup 11} cm{sup -3}. Detailed studies of the thermalization of bosonic {sup 170}Yb, {sup 172}Yb, {sup 174}Yb and {sup 176}Yb and of fermionic {sup 171}Yb each with {sup 87}Rb were performed under varying experimental conditions. The deduced total scattering cross section was clearly found to increase with higher mass of the ytterbium isotope. In general, a mass scaling of the scattering properties is in agreement with theoretical models and former experimental work. With the assumption of pure s-wave scattering, which is approximately fulfilled for the given experimental parameters, the interspecies scattering length could be derived from the measured thermalization data and was found to be (in units of the Bohr radius a{sub 0}): {sup 170}Yb-{sup 87}Rb:(18{sup +12}{sub -4})a{sub 0}, {sup 171}Yb-{sup 87}Rb:(25{sup +14}{sub -7})a{sub 0}, {sup 172}Yb-{sup 87}Rb:(33{sup +23}{sub -7})a{sub 0}, {sup 174}Yb-{sup 87}Rb:(83{sup +89}{sub -25})a{sub 0}, {sup 176}Yb-{sup 87}Rb:(127{sup +245}{sub -45})a{sub 0}. (orig./HSI)

  4. Optimized sampling of hydroperoxides and investigations of the water vapour dependence of hydroperoxide formation during ozonolysis of alkenes; Optimierung der Probenahme von Hydroperoxiden und Untersuchungen zur Wasserdampfabhaengigkeit der Bildung von Hydroperoxiden bei der Ozonolyse von Alkenen

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K.H.; Plagens, H.

    1997-06-01

    There are several sampling methods for hydroperoxides none of which is particularly reliable. The authors therefore tested three new methods in order to optimize hydroperoxide sampling and, using the optimized sampling procedure, to investigate the water vapour dependence of hydroperoxide formation during ozonolysis of alkenes. (orig.) [Deutsch] Fuer die Probenahme von Hydroperoxiden existieren verschiedene Verfahren, von denen bisher keines als besonders zuverlaessig angesehen werden konnte. Daher wurden in dieser Arbeit drei Verfahren getestet, um die Probenahme von Hydroperoxiden zu optimieren und mit dem entsprechenden Verfahren die Wasserdampfabhaengigkeit der Bildung von Hydroperoxiden bei der Ozonolyse von Alkenen zu untersuchen. (orig.)

  5. Numerical Analysis Of Buckling Of Von Mises Planar Truss

    Directory of Open Access Journals (Sweden)

    Kalina Martin

    2015-12-01

    Full Text Available A computational algorithm of a discrete model of von Mises planar steel truss is presented. The structure deformation is evaluated by seeking the minimal potential energy. The critical force invented by mathematical solution was compared with solution by computer algorithm. Symmetric and asymmetric effects of initial shape of geometric imperfection of axis of struts are used in model. The shapes of buckling of von Mises planar truss of selected vertical displacement of top joint are shown.

  6. Analytische und Effektor-Studien von N-Acyl-Ethanolaminphosphaten

    OpenAIRE

    Ates, Ebru

    2011-01-01

    Bei N-Acyl-Ethanolaminphosphaten handelt es sich um eine bislang wenig untersuchte Klasse polarer Substanzen, deren Erforschung aufgrund ihrer strukturellen Analogie zu apolaren, physiologisch wirksamen N-Acyl-Ethanolaminen von Interesse ist. Zu bear-beiten waren analytische Fragestellungen, die auch synthetische Aufgaben beinhalteten, wie Methodenentwicklung und Versuche zur Erfassung von N-Acyl-Ethanolamin-phosphaten in ausgewählten Lebensmitteln sowie strukturelle Studien zur „Bioaktivität...

  7. Spurenstoffuntersuchungen zur Bildung und Ausbreitung von Wassermassen im subpolaren Nordatlantik

    OpenAIRE

    Hildebrandt, Hauke

    2001-01-01

    In der vorliegenden Arbeit wurde ein umfangreicher Spurenstoffdatensatz aus dem subpolaren Nordatlantik erstellt und ausgewertet, der Tritium-, Helium- und Neon- sowie O-18-Messungen umfaßt. Das Hauptaugenmerk galt dabei der Bildung und Ausbreitung der tiefen Wassermassen und deren Variabilität auf Zeitskalen von einigen Jahren. Anhand von Tracermittelwerten, die mit Hilfe eines optimierten Interpolationsverfahrens gewonnen wurden, konnte gezeigt werden, daß die konvektive Neubildung de...

  8. Nash y von Neumann: mundos posibles y juegos de lenguaje

    Directory of Open Access Journals (Sweden)

    Salazar , Boris

    2004-06-01

    Full Text Available Este ensayo emplea las nociones de juego de lenguaje y de equivalencia entre juegos para examinar la decisión de John Nash de no jugar el juego coalicional que propuso John von Neumann. El argumento central es que Nash concibió una clase de mundos posibles incompatible con la de von Neumann, y que en el origen de esa divergencia estarían sus distintas nociones de racionalidad.

  9. Von Neumann's impossibility proof: Mathematics in the service of rhetorics

    Science.gov (United States)

    Dieks, Dennis

    2017-11-01

    According to what has become a standard history of quantum mechanics, in 1932 von Neumann persuaded the physics community that hidden variables are impossible as a matter of principle, after which leading proponents of the Copenhagen interpretation put the situation to good use by arguing that the completeness of quantum mechanics was undeniable. This state of affairs lasted, so the story continues, until Bell in 1966 exposed von Neumann's proof as obviously wrong. The realization that von Neumann's proof was fallacious then rehabilitated hidden variables and made serious foundational research possible again. It is often added in recent accounts that von Neumann's error had been spotted almost immediately by Grete Hermann, but that her discovery was of no effect due to the dominant Copenhagen Zeitgeist. We shall attempt to tell a story that is more historically accurate and less ideologically charged. Most importantly, von Neumann never claimed to have shown the impossibility of hidden variables tout court, but argued that hidden-variable theories must possess a structure that deviates fundamentally from that of quantum mechanics. Both Hermann and Bell appear to have missed this point; moreover, both raised unjustified technical objections to the proof. Von Neumann's argument was basically that hidden-variables schemes must violate the ;quantum principle; that physical quantities are to be represented by operators in a Hilbert space. As a consequence, hidden-variables schemes, though possible in principle, necessarily exhibit a certain kind of contextuality. As we shall illustrate, early reactions to Bohm's theory are in agreement with this account. Leading physicists pointed out that Bohm's theory has the strange feature that pre-existing particle properties do not generally reveal themselves in measurements, in accordance with von Neumann's result. They did not conclude that the ;impossible was done; and that von Neumann had been shown wrong.

  10. Räumliche Aspekte von Transformationsproblemen aus systemtheoretischer Perspektive

    OpenAIRE

    Klüter, Helmut

    2000-01-01

    Der mit dem Topos "Transformation von Wirtschafts- und Gesellschaftssystemen" axiomatisch angenommene Unvereinbarkeit sozialistischer und marktwirtschaftlicher Strukturen ist aus raumwissenschaftlicher Sicht nicht nachvollziehbar. Zum einen gibt es in Wirtschaftsgeographie und Infrastrukturtheorie eine ganze Reihe von Gemeinsamkeiten und Berührungspunkten, die man für den konstruktiven Systemumbau nutzen kann. Zum andern benötigt der Umbau selbst eine räumliche Infrastruktur. Und zum dritten ...

  11. Integration von 3D-Kamerasystemen am Gabelstapler

    OpenAIRE

    Kleinert, Steffen; Overmeyer, Ludger

    2013-01-01

    Dieser Beitrag beschreibt die Integration von laufzeitmessenden 3D Kamerasystemen in die Gabelzinkenspitzen eines Flurförderzeugs. Mit Hilfe der integrierten Kameras und deren ausgewerteter Aufnahmen wurde ein Assistenzsystem für die Handhabung von Ladungsträgern realisiert, das dem Fahrer des Flurförderzeugs Verfahrempfehlungen für die Optimierung der Relativposition zwischen Gabelzinken und Ladungsträger bzw. Lagerplatz ausgibt. Neben der Vorstellung der verwendeten Kamera-Hardware und der ...

  12. Die Darstellung von guten und schlechten Beziehungen in Kinderzeichnungen

    OpenAIRE

    Gramel, Sabine

    2005-01-01

    Nach welchen Kriterien sich Bilder, auf denen Kinder eine positive Beziehung darstellen, von Bildern unterscheiden, auf denen negative Beziehungen dargestellt sind, wurde an einer Stichprobe von 45 Kindern zwischen 4;6 und 11;6 Jahren untersucht. Die Kinder fertigten jeweils ein positives und ein negatives Beziehungsbild an. Es zeigte sich, dass die Kinder in beiden Beziehungskategorien zum großen Teil Gleichaltrige darstellten. Sie benannten für ihre Bilder Kriterien, anhand derer man die po...

  13. Zur Dialektik von Soft Skills und fachlicher Kompetenz

    OpenAIRE

    Jendrowiak, Hans-Werner

    2010-01-01

    [Der Autor stellt folgende Thesen zur Dialektik von Soft Skills und fachlicher Bildung auf:] 1. Soft Skills sind normale Bildungskategorien und Teil einer Allgemeinen Bildung. […] 2. Soft Skills sind als personalgebundene Kriterien auch immer schon Gegenstand bildungstheoretischer Debatten. […] 3. Soft Skills ist eine trendorientierte Bezeichnung für Bildung. […] 4. Soft Skills sind Ausdruck von Vorstellungen, Ideen und Theorien (Schulkultur, Unternehmenskultur, Unternehmensphilosophie). 5. S...

  14. High-efficiency diode-pumped femtosecond Yb:YAG ceramic laser

    DEFF Research Database (Denmark)

    Zhou, Binbin; Wei, Z.Y.; Zou, Y.W.

    2010-01-01

    A highly efficient diode-end-pumped femtosecond Yb:yttrium aluminum garnet (YAG) ceramic laser was demonstrated. Pumped by a 968 nm fiber-coupled diode laser, 1.9 W mode-locked output power at a repetition rate of 64.27 MHz was obtained with 3.5 W absorbed pump power, corresponding to a slope...... efficiency of 76%. Our measurement showed that the pulse duration was 418 fs with the central wavelength of 1048 nm....

  15. Fission fragment angular distribution in the reaction 28Si+176Yb

    International Nuclear Information System (INIS)

    Tripathi, R.; Sudarshan, K.; Sharma, S.K.; Reddy, A.V.R.; Pujari, P.K.; Dutta, D.; Goswami, A.; Ramachandran, K.

    2009-01-01

    Fission fragment angular distribution has been measured in the reaction 28 Si+ 176 Yb at beam energies of 145 and 155 MeV to investigate the contribution from non-compound nucleus fission. Experiments were carried out at BARC-TIFR Pelletron-LINAC accelerator facility, Mumbai. Experimental angular anisotropies in this reaction were observed to be higher than those calculated using statistical theory, indicating contribution from non-compound nucleus fission in this reaction. (author)

  16. Mode locking of Yb:GdYAG ceramic lasers with an isotropic cavity

    International Nuclear Information System (INIS)

    Xu, C W; Tang, D Y; Zhu, H Y; Zhang, J

    2013-01-01

    We report on the passive mode locking of a diode pumped Yb:GdYAG ceramic laser with a near isotropic cavity. It is found that the laser could simultaneously mode lock in the two orthogonal principal polarization directions of the cavity, and the mode locked pulses of the two polarizations have identical features and are temporally perfectly synchronized. However, their pulse energy varies out-of-phase periodically, manifesting the antiphase dynamics of mode locked lasers. (letter)

  17. Investigations on luminescence behavior of Er3+/Yb3+ co-doped boro-tellurite glasses

    Science.gov (United States)

    Maheshvaran, K.; Arunkumar, S.; Venkata Krishnaiah, K.; Marimuthu, K.

    2015-01-01

    Er3+/Yb3+ co-doped boro-tellurite glasses with the chemical composition 30TeO2+(24 - x)B2O3 + 15SrO + 10BaO + 10Li2O + 10LiF + 1Er2O3 + xYb2O3 (where x = 0, 0.1, 0.5, 1 and 2 in wt%) have been prepared and their luminescence behavior were studied and reported. Absorption spectral measurements have been used to derive the Judd-Ofelt (JO) intensity parameters from the experimental and calculated oscillator strength values following the JO theory. The various lasing parameters such as stimulated emission cross-section (σEp), experimental and calculated branching ratios (βR) and radiative lifetime (τcal) for the 2H9/2 → 4I15/2, 4S3/2 → 4I15/2 and 4I13/2 → 4I15/2 emission transitions were determined using the JO intensity parameters. The absorption and emission cross-section values for the 4I13/2 → 4I15/2 emission band have been calculated using McCumbar theory and the Gain cross-section for the 4I13/2 → 4I15/2 emission transition also obtained. The upconversion emission mechanism have been studied through various energy transfer processes and the intensity of the upconversion emission transitions are found to increase with the increase in Yb3+ ion concentration. The luminescence decay curves corresponding to the 4I13/2 → 4I15/2 transition of the Er3+/Yb3+ co-doped boro-tellurite glasses under 980 nm excitation wavelength have also been studied and reported in the present work.

  18. Yb14MnSb11 as a High-Efficiency Thermoelectric Material

    Science.gov (United States)

    Snyder, G. Jeffrey; Gascoin, Franck; Brown, Shawna; Kauzlarich, Susan

    2009-01-01

    Yb14MnSb11 has been found to be wellsuited for use as a p-type thermoelectric material in applications that involve hotside temperatures in the approximate range of 1,200 to 1,300 K. The figure of merit that characterizes the thermal-to-electric power-conversion efficiency is greater for this material than for SiGe, which, until now, has been regarded as the state-of-the art high-temperature ptype thermoelectric material. Moreover, relative to SiGe, Yb14MnSb11 is better suited to incorporation into a segmented thermoelectric leg that includes the moderate-temperature p-type thermoelectric material CeFe4Sb12 and possibly other, lower-temperature p-type thermoelectric materials. Interest in Yb14MnSb11 as a candidate high-temperature thermoelectric material was prompted in part by its unique electronic properties and complex crystalline structure, which place it in a class somewhere between (1) a class of semiconducting valence compounds known in the art as Zintl compounds and (2) the class of intermetallic compounds. From the perspective of chemistry, this classification of Yb14MnSb11 provides a first indication of a potentially rich library of compounds, the thermoelectric properties of which can be easily optimized. The concepts of the thermoelectric figure of merit and the thermoelectric compatibility factor are discussed in Compatibility of Segments of Thermo - electric Generators (NPO-30798), which appears on page 55. The traditional thermoelectric figure of merit, Z, is defined by the equation Z = alpha sup 2/rho K, where alpha is the Seebeck coefficient, rho is the electrical resistivity, and k is the thermal conductivity.

  19. Direct Observation of the Pressure-Induced Semiconductor-To-Metal Transition in Yb Monochalcogenides

    International Nuclear Information System (INIS)

    Matsunami, M.; Chen, L.; Nanba, T.; Ochiai, A.

    2003-01-01

    We have measured infrared absorption spectra under pressure and reflectivity spectra of YbS in the wide photon energy range from 7 meV to 30 eV. The absorption edge shifts linearly toward lower energy with pressure, and above 11 GPa it disappeared in the infrared energy region. The results are considered to correspond to the development of a f-d mixing above this pressure, which lead to an occurrence of the semiconductor-to- metal transition. (author)

  20. Laser Cooled YbF Molecules for Measuring the Electron's Electric Dipole Moment

    Science.gov (United States)

    Lim, J.; Almond, J. R.; Trigatzis, M. A.; Devlin, J. A.; Fitch, N. J.; Sauer, B. E.; Tarbutt, M. R.; Hinds, E. A.

    2018-03-01

    We demonstrate one-dimensional sub-Doppler laser cooling of a beam of YbF molecules to 100 μ K . This is a key step towards a measurement of the electron's electric dipole moment using ultracold molecules. We compare the effectiveness of magnetically assisted and polarization-gradient sub-Doppler cooling mechanisms. We model the experiment and find good agreement with our data.

  1. Lasing and thermal characteristics of Yb:YAG/YAG composite with atomic diffusion bonding

    Czech Academy of Sciences Publication Activity Database

    Nagisetty, Siva S.; Severová, Patricie; Miura, Taisuke; Smrž, Martin; Kon, H.; Uomoto, M.; Shimatsu, T.; Kawasaki, M.; Higashiguchi, T.; Endo, Akira; Mocek, Tomáš

    2017-01-01

    Roč. 14, č. 1 (2017), 1-6, č. článku 015001. ISSN 1612-2011 R&D Projects: GA MŠk LM2015086; GA MŠk LO1602 Institutional support: RVO:68378271 Keywords : composite Yb:YAG ceramic * atomic diffusion bonding * thermal effects Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 2.537, year: 2016

  2. Direct comparison of Yb3+-doped LiYF4 and LiLuF4 as laser media at room-temperature

    International Nuclear Information System (INIS)

    Yin, J G; Hang, Y; He, X M; Zhang, L H; Zhao, C C; Gong, J; Zhang, P X

    2012-01-01

    We present an extensive comparative analysis on the growth, the spectroscopic features, and the laser performances of room temperature Yb(5%):LiYF 4 (YLF) and Yb(5%):LiLuF 4 (LLF) crystals in the same conditions. The gain cross section, fluorescence lifetimes, laser thresholds and laser slope efficiencies are compared for the first time. It appears that Yb 3+ -doped LLF crystal might be more promising for diode-pumped high power laser operation

  3. Synthesis and upconversion luminescence properties of YF{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers derived from Y{sub 2}O{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers

    Energy Technology Data Exchange (ETDEWEB)

    Li Dan; Dong Xiangting, E-mail: dongxiangting888@163.com; Yu Wensheng; Wang Jinxian; Liu Guixia [Changchun University of Science and Technology, Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province (China)

    2013-06-15

    YF{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers were successfully fabricated via fluorination of the relevant Y{sub 2}O{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers which were obtained by calcining the electrospun PVP/[Y(NO{sub 3}){sub 3} + Yb(NO{sub 3}){sub 3} + Er(NO{sub 3}){sub 3}] composite nanofibers. The morphology and properties of the products were investigated in detail by X-ray diffraction, scanning electron microscope, transmission electron microscope, and fluorescence spectrometer. YF{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers were pure orthorhombic phase with space group Pnma and were hollow-centered structure with mean diameter of 174 {+-} 22 nm, and YF{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers are composed of nanoparticles with size in the range of 30-60 nm. Upconversion emission spectrum analysis manifested that YF{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers emitted strong green and weak red upconversion emissions centering at 523, 545, and 654 nm, respectively. The green and red emissions were, respectively, originated from {sup 2}H{sub 11/2}/{sup 4}S{sub 3/2} {yields} {sup 4}I{sub 15/2} and {sup 4}F{sub 9/2} {yields} {sup 4}I{sub l5/2} energy levels transitions of the Er{sup 3+} ions. Moreover, the emitting colors of YF{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers were located in the green region in CIE chromaticity coordinates diagram. This preparation technique could be applied to prepare other rare earth fluoride upconversion luminescence hollow nanofibers.Graphical AbstractYF{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers with orthorhombic structure were synthesized by fluorination of the electrospun Y{sub 2}O{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers via a double-crucible method using NH{sub 4}HF{sub 2} as fluorinating agent. The mean diameter of YF{sub 3}:Yb{sup 3+}/Er{sup 3+} hollow nanofibers was 174 {+-} 22 nm. The fluorination method we proposed here has been proved to be an important method, as it can not only

  4. Politische Bildung im Kontext von Regierung, Unterricht und Zucht

    Directory of Open Access Journals (Sweden)

    Thomas Rucker

    2014-02-01

    Full Text Available Johann Friedrich Herbart (1776-1841 gilt als der Begründer der wissenschaftlichen Pädagogik. In diesem Beitrag wird zu zeigen versucht, dass Herbart die Unterstützung politischer Bildung als eine Aufgabe von Regierung, Unterricht und Zucht bestimmt und in seinem Werk wichtige „Bausteine“ für eine Theorie der politischen Bildung unter den Bedingungen von Erziehung vorlegt hat. Nach Herbart ist das politische Selbst- und Weltverhältnis auf Sachverhalte bezogen, die nicht nur die Lebensführung einzelner Menschen, sondern die Lebensführung einer Mehrzahl von Menschen betreffen. Nicht das Zusammenleben von Menschen generell ist jedoch Orientierungsgesichtspunkt des politischen Selbst- und Weltverhältnisses, sondern nur das problematisch gewordene Zusammenleben. Politik ergibt sich nach Herbart aus einem Konflikt hinsichtlich der Frage, wie das Zusammenleben von Menschen geregelt sein sollte. Während die Regierung lediglich mittelbar einen Beitrag zur politischen Bildung leistet, indem sie die Voraussetzungen für Unterricht und Zucht bereitstellt, fungieren die beiden zuletzt genannten Formen von Erziehung als die eigentlichen Medien, in denen die politische Bildung im Sinne Herbarts ihren Ort hat.

  5. Preparation and luminescence properties of LaPO{sub 4}:Er,Yb nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ha-Kyun [Advanced Materials Division, Korea Research Institute of Chemical Technology, P.O. Box 107, Yuseong, Daejeon 305-600 (Korea, Republic of)]. E-mail: hakyun@krict.re.kr; Oh, Jae-Suk [Advanced Materials Division, Korea Research Institute of Chemical Technology, P.O. Box 107, Yuseong, Daejeon 305-600 (Korea, Republic of); Seok, Sang-Il [Advanced Materials Division, Korea Research Institute of Chemical Technology, P.O. Box 107, Yuseong, Daejeon 305-600 (Korea, Republic of); Lee, Tack-Hyuck [Department of Chemistry, Paichai University, Daejeon 302-735 (Korea, Republic of)

    2005-09-15

    For possible applications as optical amplification materials in telecommunications, LaPO{sub 4}:Er,Yb nanoparticles were synthesized in a solution system and their properties were investigated by various spectroscopic techniques. The prepared nanoparticles are single-phased and present the monazite structure, the particle size being about 5 nm with a narrow size distribution. Also, it was confirmed by EA and FT-IR analyses that the surface of nanoparticles is coated with the solvent molecules used in the synthesis reaction, which possibly prevents them from agglomerating. In the NIR region, the emission of the LaPO{sub 4}:Er particles is very weak due to an efficient quenching of the {sup 4}I{sub 13/2}{yields}{sup 4}I{sub 15/2} emission by the hydroxyl groups adsorbed on the surface of the nanoparticles. On the other hand, the co-doping of Yb{sup 3+} as a sensitizer in the nanoparticles resulted in the increase of the emission intensity at 1539 nm due to the effective energy transfer from Yb{sup 3+} to Er{sup 3+}. In addition, the synthesized nanoparticles have exhibited good dispersibility into a polymer matrix and effective luminescence in the NIR region.

  6. Near infra red light emitting Y2Sn2O7: Yb-Er nanoparticles

    International Nuclear Information System (INIS)

    Nigam, Sandeep; Sudarsan, V.; Vatsa, R.K.

    2011-01-01

    There is an increasing interest in erbium doped nanomaterials host, since they emit in the near-infrared region and are potential candidates for optical telecommunication, high-power and infrared lasers. Further, erbium-ytterbium-co-doped matrices have been particularly investigated as Yb 3+ ions play the role of sensitizers. In the present work, Y 2 Sn 2 O 7 nanoparticles co-doped with lanthanide ions Yb 3+ and Er 3+ were prepared based on the urea hydrolysis of Y 3+ , Sn 4+ , and Ln 3+ in ethylene glycol medium at 150 deg C followed by heating at 700 deg C. As prepared samples are amorphous in nature, and the sample heated at 700 deg C showed well crystalline pyrochlore structure. Based on TEM studies, it has been established that nano-particles are highly crystalline, with size range in the range of 2-5 nm. Luminescence measurements were carried out for the as prepared samples and those heated at 700 deg C. As prepared sampled showed very poor luminescence. However on heating to 700 deg C, strong emission in the NIR region was observed upon UV-excitation as can be seen. The peak observed around 1530 nm has been attributed to 4 I 13/2 → 4 I 15/2 transition of Er 3+ and the peak around 980 nm is due to 2 F 5/2 → 2 F 7/2 transition of Yb 3+ . (author)

  7. Synthesis and magnetic structure of the YbMn{sub 2}Sb{sub 2} compound

    Energy Technology Data Exchange (ETDEWEB)

    Morozkin, A.V. [Department of Chemistry, Moscow State University, Leninskie Gory, House 1, Building 3, GSP-2, Moscow 119992 (Russian Federation)]. E-mail: morozkin@general.chem.msu.ru; Isnard, O. [Institute Laue-Langevin, 6 Rue J. Horowitz, 38042 Grenoble (France); Henry, P. [Institute Laue-Langevin, 6 Rue J. Horowitz, 38042 Grenoble (France); Granovsky, S. [Physics Department, Moscow State University, GSP-2, 119899 Moscow (Russian Federation); Nirmala, R. [Indian Institute of Science, Bangalore (India); Manfrinetti, P. [Dipartimento di Chimica, Universita di Genova, Via Dodecaneso 31, 16146 Genova (Italy)

    2006-08-31

    A neutron diffraction investigation has been carried out on the trigonal La{sub 2}O{sub 3}-type (hP5, space group P3-bar ml, No. 164; also CaAl{sub 2}Si{sub 2}-type) YbMn{sub 2}Sb{sub 2} intermetallic. A two-step synthesis route has been tried in this work, and successfully utilised to prepare single phase samples of this compound. This study shows that YbMn{sub 2}Sb{sub 2} presents antiferromagnetic ordering below 120K. The magnetic structure of this intermetallic consists of antiferromagnetically coupled magnetic moments of the manganese atoms, in the Mn1 (1/3, 2/3, Z{sub Mn}) and Mn2 (2/3, 1/3, 1-Z{sub Mn}) sites; the direction of magnetic moments of manganese atoms forming a {phi} and a {theta} angle, respectively with the X- and the Z-axis. At 4K the magnetic moment of the Mn1 atom is {mu}{sub Mn}=3.6(1) {mu}{sub B}, with {phi}=0{sup o} and {theta}=62(4){sup o}, whilst the Mn2 atom has a magnetic moment {mu}{sub Mn}=3.6(1) {mu}{sub B}, with {phi}=0{sup o} and {theta}=242(4){sup o}. On the other hand, in this compound no local moment was detected on the Yb site.

  8. Synthesis, structure and physical properties of YbNi3Al9.23

    International Nuclear Information System (INIS)

    Tobash, P H; Ronning, F; Thompson, J D; Scott, B L; Bauer, E D; Jiang, Yu; Booth, C H

    2011-01-01

    The physical properties of YbNi 3 Al 9.23(1) , including the crystal structure, magnetization, specific heat, valence, and electrical resistivity, are reported. Single crystal x-ray diffraction reveals that the compound crystallizes with the rhombohedral space group R32 and has unit cell parameters a = 7.2443(3) A and c = 27.251(3) A with some crystallographic disorder at Al sites. The compound orders antiferromagnetically at T N = 3 K despite the presence of strong ferromagnetic correlations, accompanied by a spin-flop-like transition to a moment-aligned state above 0.1 T. X-ray absorption spectroscopy and magnetic susceptibility measurements indicate a localized Yb 3+ electronic configuration, while the Sommerfeld coefficient for the magnetically ordered state was determined as approximately 135 mJ mol -1 K -2 , suggesting moderately heavy fermion behavior. Therefore, these data indicate a balance between competing Ruderman-Kittel-Kasuya-Yosida (RKKY) and Kondo interactions in YbNi 3 Al 9.23(1) with a somewhat dominant RKKY interaction that leads to a relatively high ordering temperature.

  9. Oxygen plasma effects on zero resistance behavior of Yb,Er-doped YBCO (123) based superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, Helmut; Rathmann, Dirk [Department of Physics, Biophysics, and Photosynthesis, Freie Universitaet Berlin (Germany); Banko, Franziska; Steinhart, Martin [Physical Chemistry, Institute of Chemistry of New Materials, University of Osnabrueck (Germany); Nordmann, Joerg; Voss, Benjamin [Inorganic Chemistry, Institute of Chemistry of New Materials, University of Osnabrueck (Germany); Walder, Lorenz [Organic Chemistry, Molecular Electrochemistry, Institute of Chemistry of New Materials, University of Osnabrueck (Germany)

    2014-08-15

    Rare-earth doped YBa{sub 2}Cu{sub 3}O{sub 7-δ} samples were synthesized starting from the corresponding oxides Y{sub 2}O{sub 3}, Yb{sub 2}O{sub 3}, Er{sub 2}O{sub 3}, CuO as well as Ba(OH){sub 2} by heating to 950 C under air. The doping concentrations were adjusted to 15 % Yb, 7 % Er and 20 % Yb, 15 % Er, respectively, with respect to the yttrium content. The orthogonal phased (123) YBCO ceramics were exposed to an oxygen plasma for 140 and 380 min. Zero resistance temperature (T{sub c,0}) was determined by measuring the resistivity-temperature dependence using a classical four point measurement approach. Under optimal conditions with respect to the material composition and the oxygen treatment an unusual high zero resistance temperature of 97.5 K (T{sub c,onset} ∼ 101 K) was achieved. This represents an increase of T{sub c,0} by 7.5 K. The oxygen treatment could not be monitored by IR spectroscopy, X-ray fluorescence spectroscopy, and X-ray powder diffraction. The results showed good reproducibility. (Copyright copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Structure-Dependent Spectroscopic Properties of Yb3+-Doped Phosphosilicate Glasses Modified by SiO₂.

    Science.gov (United States)

    Wang, Ling; Zeng, Huidan; Yang, Bin; Ye, Feng; Chen, Jianding; Chen, Guorong; Smith, Andew T; Sun, Luyi

    2017-02-28

    Yb 3+ -doped phosphate glasses containing different amounts of SiO₂ were successfully synthesized by the conventional melt-quenching method. The influence mechanism of SiO₂ on the structural and spectroscopic properties was investigated systematically using the micro-Raman technique. It was worth noting that the glass with 26.7 mol % SiO₂ possessed the longest fluorescence lifetime (1.51 ms), the highest gain coefficient (1.10 ms·pm²), the maximum Stark splitting manifold of ²F 7/2 level (781 cm -1 ), and the largest scalar crystal-field N J and Yb 3+ asymmetry degree. Micro-Raman spectra revealed that introducing SiO₂ promoted the formation of P=O linkages, but broke the P=O linkages when the SiO₂ content was greater than 26.7 mol %. Based on the previous 29 Si MAS NMR experimental results, these findings further demonstrated that the formation of [SiO₆] may significantly affect the formation of P=O linkages, and thus influences the spectroscopic properties of the glass. These results indicate that phosphosilicate glasses may have potential applications as a Yb 3+ -doped gain medium for solid-state lasers and optical fiber amplifiers.

  11. Pressure dependence of the Curie temperature in the Kondo lattice compound YbNiSn

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, G; Thompson, J D [Los Alamos National Lab., NM (United States); Hamzic, A [Dept. of Physics, Zagreb (Yugoslavia)

    1992-04-03

    We have measured the magnetic susceptibility (2 K < T < 300 K) and the electrical resistivity under pressure (1.2 K < T < 300 K; p < 20 kbar) of the Kondo lattice compound YbNiSn, which may be considered as the ''hole'' analogue of the isostructural compound CeNiSn. In contrast with CeNiSn, YbNiSn does not show an energy gap at low temperatures but instead undergoes a magnetic phase transition at T{sub M} = 5.5 K. The magnetic state might be either a weakly ferromagnetic or a complex antiferromagnetic state. By applying pressure the room temperature resistance {rho}{sub RT} decreases, while T{sub M} increases. This behavior can be interpreted with respect to Doniach's Kondo necklace model as a decrease in the local exchange coupling constant J with increasing pressure, which reduces Kondo spin compensation and favors long-range magnetic order. These results show that the idea that YbNiSn is the hole counterpart to CeNiSn holds well for the properties such as dT{sub M}/dP and d{rho}{sub RT}/dP but that it fails in more detailed aspects, such as the origin of the energy gap formation. (orig.).

  12. Thermal effects on light emission in Yb3+ -sensitized rare-earth doped optical glasses

    International Nuclear Information System (INIS)

    Gouveia, E.A.; Araujo, M.T. de; Gouveia-Neto, A.S.

    2001-01-01

    The temperature effect upon infrared-to-visible frequency upconversion fluorescence emission in off-resonance infrared excited Yb 3+ -sensitized rare-earth doped optical glasses is theoretically and experimentally investigated. We have examined samples of Er3+/Yb 3+ -codoped Ga 2 S 3 :La 2 O 3 chalcogenide glasses and germanosilicate optical fibers, and Ga2O3:La 2 O 3 chalcogenide and fluoroindate glasses codoped with Pr 3+ /Yb 3+ , excited off-resonance at 1.064μm. The experimental results revealed thermal induced enhancement in the visible upconversion emission intensity as the samples temperatures were increased within the range of 20 deg C to 260 deg C. The fluorescence emission enhancement is attributed to the temperature dependent multiphonon-assisted anti-Stokes excitation process of the ytterbium-sensitizer. A theoretical approach that takes into account a sensitizer temperature dependent effective absorption cross section, which depends upon the phonon occupation number in the host matrices, has proven to agree very well with the experimental data. As beneficial applications of the thermal enhancement, a temperature tunable amplifier and a fiber laser with improved power performance are presented. (author)

  13. High-spin spectroscopy of {sup 168}Yb and the reduction of pairing correlations

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, J R.B. [Sao Paulo Univ., SP (Brazil); Stephens, F S; Deleplanque, M A; Diamond, R M [Lawrence Berkeley Lab., CA (United States); Draper, J E; Rubel, E; Duyar, C [California Univ., Davis, CA (United States); Beacker, J A; Henry, E A; Roy, N [Lawrence Livermore National Lab., CA (United States); Beausang, C W [Liverpool Univ. (United Kingdom); Frauendorf, S [Institut fur Kern und Hadronen Physik, F2-Rossendorf, Dresden (Germany)

    1992-08-01

    The high spin states of {sup 168}Yb were investigated by means of in-beam gamma spectroscopy with the High Energy Resolution Array at the 88 in. cyclotron of the Lawrence Berkeley Laboratory. The {sup 168}Yb nucleus was produced in the reaction {sup 48}Ca({sup 124}Sn,4n) at 210 MeV. Five bands previously reported were confirmed; additionally, four other bands, two extending to spins as high as 36 {Dirac_h} were observed. Cranked shell models suggest that one of the new bands can be interpreted as the continuation of the ground state band (above the AB crossing frequency) crossing into the four-quasiparticle band ABCD at about 0.38 MeV. Both relative alignment and Routhians are in good agreement with the experimental values. However, these calculations were done at constant pairing strength, which is not expected to be good at high rotational frequencies where one or more crossings have occurred in each band. Particle-hole calculations (with no pairing) were done for {sup 168}Yb as well as for other N {approx_equal} 98 nuclei for which good experimental data are available. In most cases, it is possible to associate a particle-hole configuration for each band observed at very high rotational frequencies, and the overall description is good. At frequencies below the first crossing, a full pairing calculation is necessary to describe the bands properly. At intermediate frequencies, the pairing strength is believed to be intermediate. 3 figs.

  14. Luminescence investigation of Yb3+/Er3+ codoped single LiYF4 microparticle

    International Nuclear Information System (INIS)

    Gao, Wei; Zheng, Hairong; He, Enjie; Lu, Ying; Gao, Fangqi

    2014-01-01

    Tetragonal phase LiYF 4 :Yb 3+ /Er 3+ microparticles are synthesized via facile hydrothermal method. Single LiYF 4 microparticle is excited with IR laser at 980 nm in a confocal setup, and strong green and weak red emissions are observed. It is found that single LiYF 4 :Yb 3+ /Er 3+ microparticle with sub-structure presents stronger upconversion luminescence emission and smaller intensity ratio of red to green emission than that from LiYF 4 :Yb 3+ /Er 3+ microparticle with no sub-structure. The possible mechanism, the influence of particle size and the existence of EDTA on the upconversion luminescence emission are investigated. The current study suggests that the luminescence observation with single micropaticle can effectively avoid the influence of environment and neighbor particles, which is important for investigating the luminescence properties of micro- or nano-crystals and for extending their application. - Highlights: • Single LiYF 4 microparticle is excited with IR laser at 980 nm in a confocal setup, and strong green and weak red emissions are observed. • Single LiYF 4 microparticle with different morphology exhibits different fluorescence emission intensity and intensity ratio of red to green emission. • The possible mechanism, the influence of particle size and the existence of EDTA on the upconversion emission are investigated

  15. Anharmonic behavior and structural phase transition in Yb2O3

    Directory of Open Access Journals (Sweden)

    Sugandha Dogra Pandey

    2013-12-01

    Full Text Available The investigation of structural phase transition and anharmonic behavior of Yb2O3 has been carried out by high-pressure and temperature dependent Raman scattering studies respectively. In situ Raman studies under high pressure were carried out in a diamond anvil cell at room temperature which indicate a structural transition from cubic to hexagonal phase at and above 20.6 GPa. In the decompression cycle, Yb2O3 retained its high pressure phase. We have observed a Stark line in the Raman spectra at 337.5 cm−1 which arises from the electronic transition between 2F5/2 and 2F7/2 multiplates of Yb3+ (4f13 levels. These were followed by temperature dependent Raman studies in the range of 80–440 K, which show an unusual mode hardening with increasing temperature. The hardening of the most dominant mode (Tg + Ag was analyzed in light of the theory of anharmonic phonon-phonon interaction and thermal expansion of the lattice. Using the mode Grüneisen parameter obtained from high pressure Raman measurements; we have calculated total anharmonicity of the Tg + Ag mode from the temperature dependent Raman data.

  16. Constitutive overexpression of the TaNF-YB4 gene in transgenic wheat significantly improves grain yield.

    Science.gov (United States)

    Yadav, Dinesh; Shavrukov, Yuri; Bazanova, Natalia; Chirkova, Larissa; Borisjuk, Nikolai; Kovalchuk, Nataliya; Ismagul, Ainur; Parent, Boris; Langridge, Peter; Hrmova, Maria; Lopato, Sergiy

    2015-11-01

    Heterotrimeric nuclear factors Y (NF-Ys) are involved in regulation of various vital functions in all eukaryotic organisms. Although a number of NF-Y subunits have been characterized in model plants, only a few have been functionally evaluated in crops. In this work, a number of genes encoding NF-YB and NF-YC subunits were isolated from drought-tolerant wheat (Triticum aestivum L. cv. RAC875), and the impact of the overexpression of TaNF-YB4 in the Australian wheat cultivar Gladius was investigated. TaNF-YB4 was isolated as a result of two consecutive yeast two-hybrid (Y2H) screens, where ZmNF-YB2a was used as a starting bait. A new NF-YC subunit, designated TaNF-YC15, was isolated in the first Y2H screen and used as bait in a second screen, which identified two wheat NF-YB subunits, TaNF-YB2 and TaNF-YB4. Three-dimensional modelling of a TaNF-YB2/TaNF-YC15 dimer revealed structural determinants that may underlie interaction selectivity. The TaNF-YB4 gene was placed under the control of the strong constitutive polyubiquitin promoter from maize and introduced into wheat by biolistic bombardment. The growth and yield components of several independent transgenic lines with up-regulated levels of TaNF-YB4 were evaluated under well-watered conditions (T1-T3 generations) and under mild drought (T2 generation). Analysis of T2 plants was performed in large deep containers in conditions close to field trials. Under optimal watering conditions, transgenic wheat plants produced significantly more spikes but other yield components did not change. This resulted in a 20-30% increased grain yield compared with untransformed control plants. Under water-limited conditions transgenic lines maintained parity in yield performance. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  17. Mechanism of tumor and liver concentration of /sup 111/In and /sup 169/Yb: /sup 111/In and /sup 169/Yb binding substances in tumor tissues and liver

    Energy Technology Data Exchange (ETDEWEB)

    Ando, A; Ando, I; Hiraki, T; Takeshita, M; Hisada, K

    1982-07-01

    Tumor-bearing animals were injected with /sup 111/In- and /sup 169/Yb-citrate. Tumor homogenates, from which the nuclear fraction was removed, and the mitochondrial fractions of the host livers were digested with pronase P. After digestion, the supernatants of the reaction mixtures were applied to Sephadex G-100 columns. The resultant eluates were analyzed for radioactivity, protein, uronic acid, and sialic acids. Three peaks of radioactivity were obtained by gel filtration. The first peak, eluted the void volume, contained a species whose molecular weight exceeded 40000. The second peak consisted of substances with molecular weights of 9400-40000. Radioactivity in the third peak was liberated /sup 111/In and /sup 169/Yb. These two nuclides in the second peak were bound to acid mucopolysaccharide and/or the sulfated carbohydrate chain of sulfated glycorprotein. It was thought that the nuclides in the first peak might be bound to some acid mucopolysaccharides. The second peak nuclides seemed to be bound to acid mucopolysaccharide that contained no uronic acids, and/or to the sulfated carbohydrate chain of sulfated glycoprotein. It was concluded that they were bound to the acid mucopolysaccharides and/or the sulfated carbohydrate chain of sulfated glycoprotein in tumor tissues and liver lysosomes.

  18. Prophylaxis escalation in severe von Willebrand disease: A prospective study from the von Willebrand Disease Prophylaxis Network

    NARCIS (Netherlands)

    T.C. Abshire (Thomas Calvin); J. Cox-Gill; C.L. Kempton; F.W.G. Leebeek (Frank); M. Carcao (M.); P. Kouides (P.); S. Donfield (S.); E. Berntorp

    2015-01-01

    textabstractBackground: Treatment of mucosal bleeding (epistaxis, gastrointestinal bleeding, and menorrhagia) and joint bleeding remains problematic in clinically severe von Willebrand disease (VWD). Patients are often unresponsive to treatment (e.g. desmopressin or antifibrinolytic therapy) and may

  19. Yb:Lu{sub 2}O{sub 3} hydrothermally-grown single-crystal and ceramic absorption spectra obtained between 298 and 80 K

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Cheryl A. [Snake Creek Lasers LLC, 26741 State Route 267, Friendsville, PA 18818 (United States); Department of Chemistry and Center for Optical Materials Science and Engineering Technologies, Clemson University, Clemson, SC 29634-0973 (United States); Brown, David C., E-mail: dbrown@snakecreeklasers.com [Snake Creek Lasers LLC, 26741 State Route 267, Friendsville, PA 18818 (United States); Sanjeewa, Liurukara D.; McMillen, Colin D.; Kolis, Joseph W. [Department of Chemistry and Center for Optical Materials Science and Engineering Technologies, Clemson University, Clemson, SC 29634-0973 (United States)

    2016-06-15

    The hydrothermal growth, doping, and low temperature spectral characterization of Yb doped Lu{sub 2}O{sub 3} was investigated. The absorption of the lutetia-based sesquioxide laser material Yb:Lu{sub 2}O{sub 3} at temperatures of 80, 150, 200, 250, and 298 K, in the wavelength range of 850–1100 nm are reported. Data for both single crystal and ceramic Yb:Lu{sub 2}O{sub 3} were obtained. The resulting absorption cross-section data will enable the further evaluation of Yb:Lu{sub 2}O{sub 3} as a very promising high power cryogenic laser material.

  20. Entwicklung von Extraktions- und Absorptionssystemen auf Basis ionischer Flüssigkeiten für die Entschwefelung von Kohlenwasserstoffen

    OpenAIRE

    Kuhlmann, Esther

    2008-01-01

    Da die Anforderungen an den Schwefelgehalt der fossilen Brennstoffe - nicht zuletzt durch gesetzliche Richtlinien bezüglich der Schadstoffemissionen - im Laufe der Zeit ständig gestiegen sind, sind effektive Entschwefelungsverfahren für fossile Brennstoffe von hohem Interesse. Die derzeitige Entschwefelungstechnologie basiert auf dem HDS-Verfahren, alternative Verfahren sind aber wünschenswert, insbesondere wenn Anwendungen einen Schwefelgehalt von weit unter 10 ppm erforderlich machen. Daher...

  1. Electronic Resource Management System. Vernetzung von Lizenzinformationen

    Directory of Open Access Journals (Sweden)

    Michaela Selbach

    2014-12-01

    Full Text Available In den letzten zehn Jahren spielen elektronische Ressourcen im Bereich der Erwerbung eine zunehmend wichtige Rolle: Eindeutig lässt sich hier ein Wandel in den Bibliotheken (fort vom reinen Printbestand zu immer größeren E-Only-Beständen feststellen. Die stetig wachsende Menge an E-Ressourcen und deren Heterogenität stellt Bibliotheken vor die Herausforderung, die E-Ressourcen effizient zu verwalten. Nicht nur Bibliotheken, sondern auch verhandlungsführende Institutionen von Konsortial- und Allianzlizenzen benötigen ein geeignetes Instrument zur Verwaltung von Lizenzinformationen, welches den komplexen Anforderungen moderner E-Ressourcen gerecht wird. Die Deutsche Forschungsgemeinschaft (DFG unterstützt ein Projekt des Hochschulbibliothekszentrums des Landes Nordrhein-Westfalen (hbz, der Universitätsbibliothek Freiburg, der Verbundzentrale des Gemeinsamen Bibliotheksverbundes (GBV und der Universitätsbibliothek Frankfurt, in dem ein bundesweit verfügbares Electronic Ressource Managementsystem (ERMS aufgebaut werden soll. Ein solches ERMS soll auf Basis einer zentralen Knowledge Base eine einheitliche Nutzung von Daten zur Lizenzverwaltung elektronischer Ressourcen auf lokaler, regionaler und nationaler Ebene ermöglichen. Statistische Auswertungen, Rechteverwaltung für alle angeschlossenen Bibliotheken, kooperative Datenpflege sowie ein über standardisierte Schnittstellen geführter Datenaustausch stehen bei der Erarbeitung der Anforderungen ebenso im Fokus wie die Entwicklung eines Daten- und Funktionsmodells. In the last few years the importance of electronic resources in library acquisitions has increased significantly. There has been a shift from mere print holdings to both e- and print combinations and even e-only subscriptions. This shift poses a double challenge for libraries: On the one hand they have to provide their e-resource collections to library users in an appealing way, on the other hand they have to manage these

  2. J-GLOBAL MeSH Dictionary: von Willebrand病 [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term von Willebrand病 名詞 一般 * * * * von Willebrand...病 ... MeSH D014842 200906053707829497 C LS51 UNKNOWN_2 von Willebrand 病

  3. Von Roll RCP method - first experiences; Von Roll RCP - Verfahren. Erste Erfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Capitaine, P.; Engweiler, J. [Roll Umwelttechnik AG, Zuerich (Switzerland)

    1998-09-01

    The RCP method was designed as a residue-optimised alternative to the thermally optimised grate firing of residual wastes. Its technical realisation and development to market maturity took no more than 5 years. In the first process stage the waste is converted to high-carbon pyrolysis charcoal and high-rank gas in the absence of oxygen. In the second stage these substances are oxidised by addition of oxygen. The resulting temperature causes the non-combustible constituents of the slag to melt. In a third, optional, stage this molten slag can be liberated of (heavy) metals to such an extent that it can subsequently be used directly as additive for grinding. Further exhaust gas treatment is facilitated by the use of a circulatory fluidised-bed secondary combustion chamber. Despite the reduced flue gas volume and resultant higher pollutant concentrations in the crude gas, overall emissions are lower than in conventional plants. [Deutsch] Das reststoffoptimierte RCP Verfahren ist als Alternative zur thermisch optimierten Rostverbrennung von Restabfaellen konzipiert. In nur fuenf Jahren wurde das Verfahren technisch umgesetzt und zur Marktreife entwickelt. In einer ersten Stufe des Verfahrens wird der Abfall unter Luftabschluss in einen kohlenstoffreichen Pyrolysekoks und eine heizwertreiches Gas umgesetzt. Im zweiten Schritt werden diese Stoffe unter Zugabe von Sauerstoff oxidiert. Dabei treten Temperaturen auf, bei denen die nichtbrennbaren Bestandteile der Schlacke schmelzen. Optional wird diese Schmelzschlacke in einem dritten Schritt derart von (Schwer-) Metallen befreit, dass sie anschliessend direkt als Zement-Zumahlstoff eingesetzt werden kann. Die Nutzung der zirkulierenden Wirbelschicht - Nachbrennkammer zur Abgasbehandlung vereinfacht die weitergehende Abgasbehandlung. Trotz verringertem Rauchgasvolumen und damit hoeheren Schadstoffkonzentrationen im Rohgas werden die Gesamtemissionen gegenueber konventionellen Anlagen verringert. (orig./SR)

  4. Einfluss von Informationskompetenz-Veranstaltungen auf die Qualität von Masterarbeiten

    Directory of Open Access Journals (Sweden)

    Gary Seitz

    2016-02-01

    Full Text Available Am Geographischen Institut der Universität Zürich haben die Studierenden, welche als erster Jahrgang die IK-Veranstaltung als Pflichtmodul absolvierten, ihre Masterarbeit abgeschlossen. Mit einer quantitativen Auswertung wird untersucht, ob sich die Qualität der Quellen in den Masterarbeiten verbessert hat. Dazu werden die Literaturverzeichnisse einer bibliometrischen Analyse unterzogen. Anschliessend werden die erhaltenen Werte mit denjenigen verglichen, welche von Arbeiten ohne IK-Schulung erhoben wurden. Diese Methodik könnte ein Werkzeug darstellen, um Informationskompetenz-Veranstaltungen bezüglich ihrer Relevanz für wissenschaftliches Arbeiten evaluieren zu können.

  5. "Die Toten reiten schnelle." Literarische Zitate in Briefen von und an Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Ingo Schwarz

    2007-04-01

    Full Text Available Article in GermanAbstract in English and GermanAlexander von Humboldt and his correspondents liked to enrich or embellish their letters with quotations from classic works of ancient literature as well as from recent poems, plays, or novels. This paper tries to show that references to literature were very often used in order to express thoughts and feelings more clearly not so much for impressing the recipients of letters with high education. In educated circles a good knowledge of ancient and modern works of literature was a standard requirement, which often allowed the letter writers to use quotations in a playful manner.

  6. Design of an Yb-169 source optimized for gold nanoparticle-aided radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Reynoso, Francisco J.; Manohar, Nivedh [Nuclear/Radiological Engineering and Medical Physics Programs, Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0405 (United States); Krishnan, Sunil [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Cho, Sang Hyun, E-mail: scho@mdanderson.org [Department of Radiation Physics and Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2014-10-15

    Purpose: To find an optimum design of a new high-dose rate ytterbium (Yb)-169 brachytherapy source that would maximize the dose enhancement during gold nanoparticle-aided radiation therapy (GNRT), while meeting practical constraints for manufacturing a clinically relevant brachytherapy source. Methods: Four different Yb-169 source designs were considered in this investigation. The first three source models had a single encapsulation made of one of the following materials: aluminum, titanium, and stainless steel. The last source model adopted a dual encapsulation design with an inner aluminum capsule surrounding the Yb-core and an outer titanium capsule. Monte Carlo (MC) simulations using the Monte Carlo N-Particle code version 5 (MCNP5) were conducted initially to investigate the spectral changes caused by these four source designs and the associated variations in macroscopic dose enhancement across the tumor loaded with gold nanoparticles (GNPs) at 0.7% by weight. Subsequent MC simulations were performed using the EGSnrc and NOREC codes to determine the secondary electron spectra and microscopic dose enhancement as a result of irradiating the GNP-loaded tumor with the MCNP-calculated source spectra. Results: Effects of the source filter design were apparent in the current MC results. The intensity-weighted average energy of the Yb-169 source varied from 108.9 to 122.9 keV, as the source encapsulation material changed from aluminum to stainless steel. Accordingly, the macroscopic dose enhancement calculated at 1 cm away from the source changed from 51.0% to 45.3%. The sources encapsulated by titanium and aluminum/titanium combination showed similar levels of dose enhancement, 49.3% at 1 cm, and average energies of 113.0 and 112.3 keV, respectively. While the secondary electron spectra due to the investigated source designs appeared to look similar in general, some differences were noted especially in the low energy region (<50 keV) of the spectra suggesting the

  7. Investigation of optical properties and the photocatalytic activity of synthesized YbYO4 nanoparticles and YbVO4/NiWO4 nanocomposites by polymeric capping agents

    Science.gov (United States)

    Pourmasoud, Saeid; Sobhani-Nasab, Ali; Behpour, Mohsen; Rahimi-Nasrabadi, Mehdi; Ahmadi, Farhad

    2018-04-01

    YbVO4 nanoparticles YbVO4/NiWO4 nanocomposites were synthesized by simple and new method. The effect of various polymeric capping agents such as Tween 80, Tween 20 and PEG on the shape and size of YbVO4/NiWO4 nanocomposites were investigated. YbVO4/NiWO4 nanocomposites were analyzed through some techniques including, X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, vibrating sample magnetometer (VSM), thermogravimetry differential thermal analysis (TG-DTA), transmission electron microscopy (TEM), field emission electron microscopy (FESEM), ultraviolet-visible spectroscopy (UV-Vis), and energy-dispersive X-ray spectroscopy (EDX). This attempt is the first study on the photocatalytic performance of the YbVO4/NiWO4 nanocomposites in various conditions such as size of particles and kind of dyes (rhodamine B (Rh B), methylene blue (MB), methyl orange (MO), and phenol red (Ph R)), under visible light.

  8. Richard von Volkmann: surgeon and Renaissance man.

    Science.gov (United States)

    Willy, Christian; Schneider, Peter; Engelhardt, Michael; Hargens, Alan R; Mubarak, Scott J

    2008-02-01

    Richard von Volkmann (1830-1889), one of the most important surgeons of the 19(th) century, is regarded as one of the fathers of orthopaedic surgery. He was a contemporary of Langenbeck, Esmarch, Lister, Billroth, Kocher, and Trendelenburg. He was head of the Department of Surgery at the University of Halle, Germany (1867-1889). His popularity attracted doctors and patients from all over the world. He was the lead physician for the German military during two wars. From this experience, he compared the mortality of civilian and war injuries and investigated the general poor hygienic conditions in civilian hospitals. This led him to introduce the "antiseptic technique" to Germany that was developed by Lister. His powers of observation and creativity led him to findings and achievements that to this day bear his name: Volkmann's contracture and the Hueter-Volkmann law. Additionally, he was a gifted writer; he published not only scientific literature but also books of children's fairy tales and poems under the pen name of Richard Leander, assuring him a permanent place in the world of literature as well as orthopaedics.

  9. Geschichte der Natur bei Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Christian Helmreich

    2009-05-01

    Full Text Available Article in German, Abstracts in English, German and French.This article analyses the importance of an historical view of nature in the works of Alexander von Humboldt. In several of his first writings, Humboldt seems to outline the importance of what one may call history of nature. But even before his famous American travel, his position changed and he became reluctant to accept the seriousness of historical enquiry in the area of natural sciences: if we want to reconstruct the past state of nature, we cannot rely on empirical proofs; and history of nature is therefore necessarily based on uncertain hypotheses. Humboldt kept his sceptical attitude in the first decades of the 19th century, despite the positive results of the palaeontological researches of his scientific colleagues. However, he gradually convinced himself of the scientific interest of historical investigations in the natural sciences. The Cosmos paradoxally displays two apparently conflicting points of view: in his methodological remarks, Humboldt maintains that precise accounts of the past state of nature are out of reach of human knowledge, yet elsewhere in the same Cosmos he gives broad and rather vivid descriptions of the eventful history of nature.

  10. Hypercontractivity in group Von Neumann algebras

    CERN Document Server

    Junge, Marius; Parcet, Javier

    2017-01-01

    In this paper, the authors provide a combinatorial/numerical method to establish new hypercontractivity estimates in group von Neumann algebras. They illustrate their method with free groups, triangular groups and finite cyclic groups, for which they obtain optimal time hypercontractive L_2 \\to L_q inequalities with respect to the Markov process given by the word length and with q an even integer. Interpolation and differentiation also yield general L_p \\to L_q hypercontrativity for 1 < p \\le q < \\infty via logarithmic Sobolev inequalities. The authors' method admits further applications to other discrete groups without small loops as far as the numerical part-which varies from one group to another-is implemented and tested on a computer. The authors also develop another combinatorial method which does not rely on computational estimates and provides (non-optimal) L_p \\to L_q hypercontractive inequalities for a larger class of groups/lengths, including any finitely generated group equipped with a condit...

  11. Nuclear detection of Y-box protein-1 (YB-1) closely associates with progesterone receptor negativity and is a strong adverse survival factor in human breast cancer

    International Nuclear Information System (INIS)

    Dahl, Edgar; Dunn, Sandra E; Mertens, Peter R; En-Nia, Abdelaziz; Wiesmann, Frank; Krings, Renate; Djudjaj, Sonja; Breuer, Elisabeth; Fuchs, Thomas; Wild, Peter J; Hartmann, Arndt

    2009-01-01

    Y-box binding protein-1 (YB-1) is the prototypic member of the cold shock protein family that fulfills numerous cellular functions. In the nucleus YB-1 protein orchestrates transcription of proliferation-related genes, whereas in the cytoplasm it associates with mRNA and directs translation. In human tumor entities, such as breast, lung and prostate cancer, cellular YB-1 expression indicates poor clinical outcome, suggesting that YB-1 is an attractive marker to predict patients' prognosis and, potentially, is suitable to individualize treatment protocols. Given these predictive qualities of YB-1 detection we sought to establish a highly specific monoclonal antibody (Mab) for diagnostic testing and its characterization towards outcome prediction (relapse-free and overall survival). Hybridoma cell generation was carried out with recombinant YB-1 protein as immunogen and Mab characterization was performed using immunoblotting and ELISA with recombinant and tagged YB-1 proteins, as well as immunohistochemistry of healthy and breast cancer specimens. Breast tumor tissue array staining results were analyzed for correlations with receptor expression and outcome parameters. YB-1-specific Mab F-E2G5 associates with conformational binding epitopes mapping to two domains within the N-terminal half of the protein and detects nuclear YB-1 protein by immunohistochemistry in paraffin-embedded breast cancer tissues. Prognostic evaluation of Mab F-E2G5 was performed by immunohistochemistry of a human breast cancer tissue microarray comprising 179 invasive breast cancers, 8 ductal carcinoma in situ and 37 normal breast tissue samples. Nuclear YB-1 detection in human breast cancer cells was associated with poor overall survival (p = 0.0046). We observed a close correlation between nuclear YB-1 detection and absence of progesterone receptor expression (p = 0.002), indicating that nuclear YB-1 detection marks a specific subgroup of breast cancer. Likely due to limitation of sample

  12. Ytterbium doped silicon clusters YbSi{sub n} (n = 4–10) and their anions: Structures, thermochemistry, and electron affinities

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Xiaohong [School of Chemical Engineering, Inner Mongolia University of Technology, Hohhot 010051 (China); Hao, Dongsheng [School of Chemical Engineering, Inner Mongolia University of Technology, Hohhot 010051 (China); School of Mining and Technology, Inner Mongolia University of Technology, Hohhot 010051 (China); Yang, Jucai, E-mail: yangjc@imut.edu.cn [School of Chemical Engineering, Inner Mongolia University of Technology, Hohhot 010051 (China); School of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot 010051 (China)

    2015-11-05

    Highlights: • The ground-state structure of YbSi{sub n} and its anion is substitutional structure. • The four DFT AEAs are in excellent agreement with the experimental data. • Theoretical AEA of 2.33 eV of YbSi{sub 9} is more reasonable than the experimental 2.60 eV. • Hardness analysis reveals that doping Yb to Si{sub n} raises photochemical sensitivity. • Relative stabilities of YbSi{sub n} and their anions are examined. - Abstract: The structures, electron affinities, dissociation energies, hardness, and dipole moments of YbSi{sub n} (n = 4–10) and their anions were examined using B3LYP, TPSSh, PBE and wB97X methods. The lowest-energy structures can be regarded as replacing a Si of the ground-state structure of Si{sub n+1} with a Yb atom. The theoretical adiabatic electron affinities (AEAs) of YbSi{sub n} are in excellent agreement with experimental data. The average absolute errors from experiment are by 0.08, 0.07, 0.05 and 0.08 eV at the B3LYP, the TPSSh, the PBE and the wB97X levels, respectively. Theoretical AEAs of 2.33 ± 0.05 eV for YbSi{sub 9} are more reliable than the experimental value of 2.60 ± 0.05 eV. The hardness analysis reveals that doping Yb atom to Si{sub n} (n = 4–10) clusters raises the photochemical sensitivity. The dissociation energies of Yb atom from YbSi{sub n} and their anions were calculated to examine relative stabilities.

  13. Broadband downshifting luminescence in Cr³⁺₋Yb³⁺ codoped garnet for efficient photovoltaic generation.

    Science.gov (United States)

    Ye, Song; Zhou, Jiajia; Wang, Shiting; Hu, Rongxuan; Wang, Deping; Qiu, Jianrong

    2013-02-25

    The Cr³⁺₋Yb³⁺ codoped YAG crystals were synthesized by the solid state reaction method, in which the intense near-infrared emission around 1000 nm originated from Yb³⁺ ²F₅/₂ →²F₇/₂ transition was obtained due to the efficient energy transfer from Cr³⁺ to Yb³⁺. The stable and transient spectral measurements revealed that the phonon assistant energy transfer process is responsible for the energy transfer from Cr³⁺ to Yb³⁺ upon both the excitations of Cr³⁺: ⁴T₁ and ⁴T₂> energy levels. Due to the effective absorption of Cr³⁺ in the visible region in YAG and the efficient energy transfer to Yb³⁺, this material can be developed as spectral convertors to improve silicon solar cell photovoltaic conversion efficiency.

  14. Spin re-orientation in heavy fermion system α - YbAl1 - x FexB4

    Science.gov (United States)

    Wu, Shan; Broholm, C.; Kuga, K.; Suzuki, Shintaro; Nakatsuji, S.; Mourigal, M.; Stone, M.; Tian, Wei; Qiu, Y.; Rodriguez-Rivera, Jose

    Non centro-symmetric α - YbAlB4 has a heavy Fermi liquid ground state and shares many characteristics with centro-symmetric β - YbAlB4 . Both isomorphs display intermediate valence, associated with a fluctuation scale of T0 = 200 K and a Kondo lattice scale of T* = 8 K. Unlike β - YbAlB4 , α - YbAlB4 is at the boundary of a transition from a Fermi liquid metallic state to an antiferromagnetic (AFM) insulating state, driven by Fe substitution of Al. Magnetization and specific heat measurements reveal two different antiferromagnetic phases with TN = 9 K and TN = 2 K for Fe concentration above and below x =0.07. We report single crystal neutron scattering experiments on Fe doped YbAlB4 with x =0.035 and x =0.125. While the ordering wave vector is identical, k -> = (1 , 0 , 0) , the spin orientation switches from c to a with increasing Fe concentration. This suggests different anisotropic hybridization between 4f and conduction electrons that we confirmed by determining the crystal field levels. Supported by DOE, BES through DE-FG02-08ER46544.

  15. Acquired von Willebrand syndrome: A rare disorder of heterogeneous etiology

    Directory of Open Access Journals (Sweden)

    P Kasatkar

    2013-01-01

    Full Text Available Context: Acquired von Willebrand syndrome (AVWS is a rare bleeding disorder that mimics the inherited form of von Willebrand disease (VWD in terms of laboratory findings and clinical presentation. Aims: To study the etiology of acquired VWD. Settings and Design: The patients referred from various hospitals in and out of Mumbai were included in the study. Materials and Methods: Six patients with AVWS diagnosed at this center over the last 10 years were analyzed against 171 patients with inherited VWD. The differential diagnosis of AVWS was made based on reduced levels of von Willebrand antigen and von Willebrand ristocetin cofactor, decrease in ristocetin induced platelet aggregation, absence of correction in mixing studies with no prior history of bleeding problems and a negative family history for bleeding disorders. Results: In three patients, the disease was associated with systematic lupus erythematosus, out of which one was also associated with Kikuchi lymphadenitis and second with autoimmune hemolytic anemia. Fourth case was associated with hypothyroidism and fifth was a case of dermatitis and vitiligo. The last patient was a case of hemophilia A with Burkitts lymphoma, who developed autoantibodies to von Willebrand factor. Except two patients, all other patients responded to immune suppressive therapy with corticosteroids, while the patient with hypothyroidism responded to oral thyroxine. Conclusion: AVWS is a rare condition and may often be missed or diagnosed as inherited disease associated with heterogeneous disease conditions.

  16. Ecobalance of natural gas vehicles; Oekobilanz von Erdgasfahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Nigge, K.M. [Simon, Kucher und Partners Strategy und Marketing Consultants GmbH, Bonn (Germany)

    2000-07-01

    The impacts on human health and the natural environment of using natural gas, Diesel and petrol as fuels for city buses and passenger cars are compared in a Life Cycle Assessment. In addition to the burning of the fuels in the engines, this assessment also comprises the upstream processes of the fuel supply chain. Despite the increased energy demand of the vehicles, natural gas is associated with the lowest impacts overall for both city buses and passenger cars. The health impacts that can be avoided through the use of natural gas instead of Diesel or petrol thereby differ only weakly between the use of the vehicles in cities of various sizes within Germany. From the perspective of environmental protection, the market introduction of natural gas vehicles therefore does not need remain limited to large cities within agglomerated regions. (orig.) [German] Die Auswirkungen der Verwendung von Erdgas, Diesel und Benzin als Kraftstoffe fuer Stadtbusse und Pkw auf die menschliche Gesundheit und die natuerliche Umwelt werden in einer Oekobilanz verglichen. Diese umfasst neben der motorischen Verbrennung der Kraftstoffe auch die vorgelagerten Prozessketten der Kraftstoffbereitstellung. Sowohl fuer Stadtbusse als auch fuer Pkw schneidet Erdgas trotz eines energetischen Mehrbedarfes der Fahrzeuge insgesamt am guenstigsten ab. Die durch den Einsatz von Erdgas anstelle von Diesel oder Benzin vermeidbaren Gesundheitsschaeden unterscheiden sich dabei zwischen einem Einsatz der Fahrzeuge in Staedten verschiedener Groesse innerhalb von Deutschland nur wenig. Die Markteinfuehrung von Erdgasfahrzeugen muss also aus Sicht des Umweltschutzes nicht auf grosse Staedte in Ballungsgebieten beschraenkt bleiben. (orig.)

  17. Effect of Structural Stress on the Laser Quality of Highly Doped Yb:KY(WO4)2/KY(WO4)2 and Yb:KLu(WO4)2/KLu(WO4)2 Epitaxial Structures

    International Nuclear Information System (INIS)

    Carvajal, J.; Raghothamachar, B.; Silvestre, O.; Chen, H.; Pujol, M.; Petrov, V.; Dudley, M.; Aguilo, M.; Diaz, F.

    2009-01-01

    In this communication we demonstrate how the difference in laser performance of two highly doped (20 at %) epitaxial layers of Yb-doped KY(WO4)2 (KYW) grown on a KYW substrate and Yb-doped KLu(WO4)2 (KLuW) grown on a KLuW substrate, respectively, is related to the presence of structural stress in the epilayers, investigated by synchrotron white beam X-ray topography. From the results obtained, it is clear that the samples that show a larger amount of structural stress, Yb:KYW/KYW epitaxies, lead to lower efficiency in laser operation, giving a direct correlation between the existence and magnitude of such structural stress and the loss in efficiency of laser performance in such epitaxial layers which, from a spectroscopical point of view, are otherwise equivalent.

  18. Formation of Deep Electron Trap by Yb3+ Codoping Leads into Super-Long Persistent Luminescence in Ce3+-doped Yttrium Aluminum Gallium Garnet Phosphors.

    Science.gov (United States)

    Ueda, Jumpei; Miyano, Shun; Tanabe, Setsuhisa

    2018-05-23

    The Y 3 Al 2 Ga 3 O 12 :Ce 3+ -Cr 3+ compound is one of the brightest persistent phosphors, but its persistent luminescence (PersL) duration is not so long due to the relatively shallow Cr 3+ electron trap. Comparing the vacuum referred binding energy of the electron trapping state by Cr 3+ and those by lanthanide ions, we selected Yb 3+ as a deeper electron trapping center. The Y 3 Al 2 Ga 3 O 12 :Ce 3+ -Yb 3+ phosphors show Ce 3+ :5d→4f green persistent luminescence after ceasing blue light excitation. The formation of Yb 2+ was confirmed by the increased intensity of absorption at 585 nm during the charging process. This result indicates that the Yb 3+ ions act as electron traps by capturing an electron. From the thermoluminescence glow curves, it was found the Yb 3+ trap makes much deeper electron trap with 1.01 eV depth than the Cr 3+ electron trap with 0.81 eV depth. This deeper Yb 3+ trap provides much slower detrapping rate of filled electron traps than the Cr 3+ -codoped persistent phosphor. In addition, by preparing transparent ceramics and optimizing Ce 3+ and Yb 3+ concentrations, the Y 3 Al 2 Ga 3 O 12 :Ce 3+ (0.2%)-Yb 3+ (0.1%) as-made transparent ceramic phosphor showed super long persistent luminescence for over 138.8 hours after ceasing blue light charging.

  19. Overexpression of YB1 C-terminal domain inhibits proliferation, angiogenesis and tumorigenicity in a SK-BR-3 breast cancer xenograft mouse model.

    Science.gov (United States)

    Shi, Jian-Hong; Cui, Nai-Peng; Wang, Shuo; Zhao, Ming-Zhi; Wang, Bing; Wang, Ya-Nan; Chen, Bao-Ping

    2016-01-01

    Y-box-binding protein 1 (YB1) is a multifunctional transcription factor with vital roles in proliferation, differentiation and apoptosis. In this study, we have examined the role of its C-terminal domain (YB1 CTD) in proliferation, angiogenesis and tumorigenicity in breast cancer. Breast cancer cell line SK-BR-3 was infected with GFP-tagged YB1 CTD adenovirus expression vector. An 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) proliferation assay showed that YB1 CTD decreased SK-BR-3 cell proliferation, and down-regulated cyclin B1 and up-regulated p21 levels in SK-BR-3 cells. YB1 CTD overexpression changed the cytoskeletal organization and slightly inhibited the migration of SK-BR-3 cells. YB1 CTD also inhibited secreted VEGF expression in SK-BR-3 cells, which decreased SK-BR-3-induced EA.hy926 endothelial cell angiogenesis in vitro. YB1 CTD overexpression attenuated the ability of SK-BR-3 cells to form tumours in nude mice, and decreased in vivo VEGF levels and angiogenesis in the xenografts in SK-BR-3 tumour-bearing mice. Taken together, our findings demonstrate the vital role of YB1 CTD overexpression in inhibiting proliferation, angiogenesis and tumorigenicity of breast cancer cell line SK-BR-3.

  20. A unified calculation of the optical spectral band positions and electron paramagnetic resonance spectral data for Yb3+ in InP semiconductor

    International Nuclear Information System (INIS)

    Feng Wenlin; Zheng Wenchen; Liu Honggang; Li, X.M.

    2011-01-01

    Highlights: → We found a energy matrix of 4f 13 ion in cubic crystals and external magnetic field. → Optical and EPR data of Yb 3+ : InP are explained by diagonalizing the energy matrix. → Signs of hyperfine structure constants A( 171 Yb 3+ ) and A( 173 Yb 3+ ) are determined. - Abstract: The complete energy matrix for a 4f 13 ion in cubic crystals and under an external magnetic field is established by means of the irreducible tensor operator and/or equivalent operator methods. By diagonalizing the energy matrix, four optical spectrum band positions and three spin-Hamiltonian parameters [g factor and hyperfine structure constants A( 171 Yb 3+ ) and A( 173 Yb 3+ )] for Yb 3+ in InP semiconductor are calculated together. The calculated results are in good agreement with the experimental values. The signs of hyperfine structure constants A( 171 Yb 3+ ) and A( 173 Yb 3+ ) are determined from the calculations. The results are discussed.

  1. Defects induced in Yb3+/Ce3+ co-doped aluminosilicate fiber glass preforms under UV and γ-ray irradiation

    DEFF Research Database (Denmark)

    Chiesa, Mario; Mattsson, Kent Erik; Taccheo, Stefano

    2014-01-01

    A set of Ce-/Yb-co-doped silica optical fiber preform cores, differing in terms of dopant concentrations are studied by Electron Paramagnetic Resonance (EPR) spectroscopy before and after irradiation of the samples with excimer UV laser light and γ-rays. Evidence of Yb3+ clustering in the case...

  2. A comprehensive phononics of phonon assisted energy transfer in the Yb3+ aided upconversion luminescence of Tm3+ and Ho3+ in solids

    International Nuclear Information System (INIS)

    Debnath, Radhaballabh; Bose, Saptasree

    2015-01-01

    The theory of phonon assisted energy transfer is being widely used to explain the Yb 3+ ion aided normal and upconversion emission of various rare earth ions in different Yb 3+ co-doped solids. The reported phonon dynamics in many of these studies are either incomplete or erroneous. Here we report Yb 3+ aided upconversion luminescence properties of Tm 3+ and Ho 3+ in (Yb 3+ /Tm 3+ ) and (Yb 3+ /Ho 3+ ) co-doped two BaO–tellurite glasses and explain their phononics in the light of Dexter's theory by proposing a comprehensive scheme. The approach is valid for other systems of different phonon structures. - Highlights: • Yb 3+ aided upconversion luminescence properties of Tm 3+ and Ho 3+ in (Yb 3+ /Tm 3+ ) and (Yb 3+ /Ho 3+ ) co-doped two BaO–tellurite glasses, are reported. • Phonon assisted energy transfer in these systems are explained in the light of Dexter's theory by proposing a comprehensive scheme of phononics. • The approach is valid for other systems of different phonon structures

  3. Effect of F- ions on physical and spectroscopic properties of Yb3+-doped TeO2-based glasses

    International Nuclear Information System (INIS)

    Wang Guonian; Dai Shixun; Zhang Junjie; Xu Shiqing; Hu Lili; Jiang Zhonghong

    2005-01-01

    The effects of F - ions on physical and spectroscopic properties of the Yb 3+ in tellurite glass system are investigated. The results show that the glass system takes on good thermal stability with the content of ZnF 2 lower than 15 mol%, both the emission cross-section and the fluorescence lifetime of Yb 3+ ions increase evidently which indicate that such oxyfluoride tellurite glass system is a promising laser host matrix for high power generation. FT-IR spectra were used to analyze the effect of F- ions on the structure of tellurite glasses and OH - groups in this glass system. Analysis demonstrates that addition of fluoride decreases the symmetry of the structure of tellurite glasses which increases the emission cross-section and removes the OH - groups, and which improves the measured fluorescence lifetime of Yb 3+ ions

  4. Quantum sized Ag nanocluster assisted fluorescence enhancement in Tm3+-Yb3+ doped optical fiber beyond plasmonics

    International Nuclear Information System (INIS)

    Chattopadhyay, Rik; Haldar, Arindam; Paul, Mukul C.; Das, Shyamal; Bhadra, Shyamal K.

    2015-01-01

    We report a process for enhancing fluorescence emission from conventional rare earth ions in optical fiber by metal nanocluster (MNC) in nonresonant indirect pumping. The process is completely different from formal metal enhanced fluorescence phenomenon as the MNCs are too small in size to support localized surface plasmon and the excitation wavelength is far from plasmon resonance frequency. We used an established theory of two coupled oscillators to explain the simultaneous enhancement of Ytterbium (Yb 3+ ) and Thulium (Tm 3+ ) emission by silver (Ag) NCs under nonresonant pumping in optical fiber. The fiber is pumped with a 980 nm fiber pigtailed laser diode with input power of 20–100 mW to excite the Yb 3+ . Four times enhancement of Yb 3+ emission of 900–1100 nm and Tm 3+ upconversion emission around 474 nm, 650 nm, and 790 nm is observed in the fiber with Ag NCs

  5. Room temperature diode-pumped Yb:CaYAlO4 laser with near quantum limit slope efficiency

    International Nuclear Information System (INIS)

    Tan, W D; Tang, D Y; Zhang, J; Xu, C W; Cong, Z H; Xu, X D; Li, D Z; Xu, J

    2011-01-01

    The room temperature continuous wave (CW) laser performance of a compact Yb:CaYAlO 4 (Yb:CYA) laser with near quantum limit slope efficiency is demonstrated. Pumped with a CW diode operating at 979 nm, the laser emitted a maximum CW output power of 2.3 W at 1050 nm. The corresponding slope efficiency was found to be 92% while the optical to optical conversion efficiency was 70%. The laser can also be continuously tuned from 1008 nm to 1063 nm using an intra-cavity SF 10 prism. The round trip cavity losses of Yb:CYA was 0.6% while the loss coefficient of the crystal was 0.01 cm -1

  6. Color Tunable and Upconversion Luminescence in Yb-Tm Co-Doped Yttrium Phosphate Inverse Opal Photonic Crystals.

    Science.gov (United States)

    Wang, Siqin; Qiu, Jianbei; Wang, Qi; Zhou, Dacheng; Yang, Zhengwen

    2016-04-01

    For this paper, YPO4: Tm, Yb inverse opals with the photonic band gaps at 475 nm and 655 nm were prepared by polystyrene colloidal crystal templates. We investigated the influence of photonic band gaps on the Tm-Yb upconversion emission which was in the YPO4: Tm Yb inverse opal photonic crystals. Comparing with the reference sample, significant suppression of both the blue and red upconversion luminescence of Tm3+ ions were observed in the inverse opals. The color purity of the blue emission was improved in the inverse opal by the suppression of red upconversion emission. Additionally, mechanism of upconversion emission in the inverse opal was discussed. We believe that the present work will be valuable for not only the foundational study of upconversion emission modification but also the development of new optical devices in upconversion lighting and display.

  7. Resonantly cladding-pumped Yb-free Er-doped LMA fiber laser with record high power and efficiency.

    Science.gov (United States)

    Zhang, Jun; Fromzel, Viktor; Dubinskii, Mark

    2011-03-14

    We report the results of our power scaling experiments with resonantly cladding-pumped Er-doped eye-safe large mode area (LMA) fiber laser. While using commercial off-the-shelf LMA fiber we achieved over 88 W of continuous-wave (CW) single transverse mode power at ~1590 nm while pumping at 1532.5 nm. Maximum observed optical-to-optical efficiency was 69%. This result presents, to the best of our knowledge, the highest power reported from resonantly-pumped Yb-free Er-doped LMA fiber laser, as well as the highest efficiency ever reported for any cladding-pumped Er-doped laser, either Yb-co-doped or Yb-free.

  8. Numerical estimation of phase transformations in solid state during Yb:YAG laser heating of steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Kubiak, Marcin, E-mail: kubiak@imipkm.pcz.pl; Piekarska, Wiesława; Domański, Tomasz; Saternus, Zbigniew [Institute of Mechanics and Machine Design Foundations, Częstochowa University of Technology, Dąbrowskiego 73, 42-200 Częstochowa (Poland); Stano, Sebastian [Welding Technologies Department, Welding Institute, Błogosławionego Czesława 16-18, 44-100 Gliwice (Poland)

    2015-03-10

    This work concerns the numerical modeling of heat transfer and phase transformations in solid state occurring during the Yb:YAG laser beam heating process. The temperature field is obtained by the numerical solution into transient heat transfer equation with convective term. The laser beam heat source model is developed using the Kriging interpolation method with experimental measurements of Yb:YAG laser beam profile taken into account. Phase transformations are calculated on the basis of Johnson - Mehl - Avrami (JMA) and Koistinen - Marburger (KM) kinetics models as well as continuous heating transformation (CHT) and continuous cooling transformation (CCT) diagrams for S355 steel. On the basis of developed numerical algorithms 3D computer simulations are performed in order to predict temperature history and phase transformations in Yb:YAG laser heating process.

  9. A low temperature study of antiferromagnetic YbVO{sub 4} by NMR thermally detected by nuclear orientation

    Energy Technology Data Exchange (ETDEWEB)

    Hutchison, W.D.; Prandolini, M.J.; Harker, S.J.; Chaplin, D.H. [Australian Defence Force Academy, School of Physics, University College, University of New South Wales (Australia); Bowden, G.J. [University of New South Wales, School of Physics (Australia); Bleaney, B. [Clarendon Laboratory (United Kingdom)

    1999-09-15

    NMR-TDNO results using an external {sup 60}CoCo (hcp) nuclear orientation thermometer for non-irradiated, single crystal, antiferromagnetic YbVO{sub 4} are compared with those obtained earlier with neutron activated samples using both internal and external {gamma}-ray thermometers. Detailed comparisons are made for the {sup 171}Yb (I=1/2, 14.31% abundant) stable nucleus. This strongly asymmetric, largely homogeneous, resonance lineshape was retained and is readily power broadened. Extremely broad, field-dependent homogeneous thermometric responses are observed in the expected frequency range for the quadrupolar stable nucleus {sup 173}Yb (I=5/2, 16.13% abundant) for both irradiated and non-irradiated samples.

  10. High-Pressure Synthesis and Characterization of the Ammonium Yttrium Borate (NH4)YB8O14.

    Science.gov (United States)

    Schmitt, Martin K; Podewitz, Maren; Liedl, Klaus R; Huppertz, Hubert

    2017-11-20

    The first high-pressure yttrium borate (NH 4 )YB 8 O 14 was synthesized at 12.8 GPa/1300 °C using a Walker-type multianvil module. The compound crystallizes in the orthorhombic space group Pnma (no. 62) with the lattice parameters a = 17.6375(9), b = 10.7160(5), and c = 4.2191(2) Å. (NH 4 )YB 8 O 14 constitutes a novel structure type but exhibits similarities to the crystal structure of β-BaB 4 O 7 . X-ray single-crystal and powder diffraction, EDX, vibrational spectroscopy as well as quantum chemical calculations were used to characterize (NH 4 )YB 8 O 14 .

  11. Analysis of structure origin and luminescence properties of Yb(3+)-Er(3+) co-doped fluorophosphate glass.

    Science.gov (United States)

    Chen, Fangze; Jing, Xufeng; Wei, Tao; Wang, Fengchao; Tian, Ying; Xu, Shiqing

    2014-08-14

    The near infrared luminescence properties of Yb(3+)-Er(3+) co-doped fluorophosphate glasses have been investigated. The various effects on structure and 1.53 μm emission were analyzed as a function of Yb(3+) concentration. The energy transfer mechanism was proposed. High measured lifetime (10.75 ms), large effective full widths at half maximum (73.71 nm) and large gain per unit length (62.8 × 10(-)(24)cm(2)s) have been achieved in prepared glass. The present glass co-doped with 6mol% YbF3 and 2 mol% ErF3 showed magnificent luminescence properties for telecommunication application. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Nanocrystal in Er3+-doped SiO2-ZrO2 Planar Waveguide with Yb3+ Sensitizer

    International Nuclear Information System (INIS)

    Razaki, N. Iznie; Jais, U. Sarah; Abd-Rahman, M. Kamil; Bhaktha, S. N. B.; Chiasera, A.; Ferrari, M.

    2010-01-01

    Higher doping of Er 3+ in glass ceramic waveguides would cause concentration and pair-induced quenching which lead to inhomogeneous line-width of luminescence spectrum thus reduce output intensity. Concentration quenching can be overcome by introducing ZrO 2 in the glass matrix while co-doping with Yb 3+ which acts as sensitizer would improve the excitation efficiency of Er 3+ . In this study, SiO 2 -ZrO 2 planar waveguides having composition in mol percent of 70SiO 2 -30ZrO 2 doped with Er 3+ and co-doped with Yb 3+ , were prepared via sol-gel route. Narrower and shaper peaks of PL and XRD shows the formation of nanocrystals. Intensity is increase with addition amount of Yb 3+ shows sensitizing effect on Er 3+ .

  13. Highly efficient actively Q-switched Yb:LGGG laser generating 3.26 mJ of pulse energy

    Science.gov (United States)

    Li, Yanbin; Zhang, Jian; Zhao, Ruwei; Zhang, Baitao; He, Jingliang; Jia, Zhitai; Tao, Xutang

    2018-05-01

    An efficient acousto-optic Q-switched laser operation of Yb:(LuxGd1-x)3Ga5O12 (x = 0.062) (Yb:LGGG) crystal is demonstrated, producing stable pulses with repetition rate ranging from 1 to 20 kHz. Under the absorbed pump power of 8.75 W, the maximum average output power of 3.26 W is obtained at the pulse repletion rate of 1 kHz, corresponding to the slope efficiency as high as 52%. The pulse width of 14.5 ns is achieved with the pulse energy and peak power of 3.26 mJ and 225 kW, respectively. It indicates great potential of Yb:LGGG crystal for generating pulsed lasers.

  14. NIR to visible frequency upconversion in Er3+ and Yb3+ codoped ZrO2 phosphor

    International Nuclear Information System (INIS)

    Singh, Vijay; Kim, Sang Hwan; Rai, Vineet Kumar; Al-Shamery, Katharina; Haase, Markus

    2013-01-01

    The ZrO 2 :Er 3+ codoped with Yb 3+ phosphor powders have been prepared by the urea combustion route. Formation of the compounds ZrO 2 :Er 3+ and ZrO 2 :Er 3+ , Yb 3+ was confirmed by XRD. The frequency upconversion emissions in the green and red regions upon excitation with a CW diode laser at ∝978 nm are reported. Codoping with Yb 3+ enhances the emission intensities of the triply ionized erbium in the green and red spectral regions by about ∝130 and ∝820 times respectively. The emission properties of the ZrO 2 :Er 3+ phosphor powders are discussed on the basis of excited state absorption, energy transfer, and cross-relaxation energy transfer mechanisms. (orig.)

  15. Proof of pipeline strength based on measurements of inspection pigs; Festigkeitsnachweis von Pipelines aufgrund der Messergebnisse von Pruefmolchen

    Energy Technology Data Exchange (ETDEWEB)

    De la Camp, H.J.; Feser, G.; Hofmann, A.; Wolf, B.; Schmidt, H. [TUeV Sueddeutschland Bau und Betrieb GmbH, Muenchen (Germany); Herforth, H.E.; Juengling, K.H.; Schmidt, W. [TUeV Anlagentechnik GmbH, Berlin-Schoeneberg (Germany). Unternehmensgruppe TUeV Rheinland/Berlin-Brandenburg

    2002-01-01

    The report is aimed at collecting and documenting the state of the art and the extensive know how of experts and pipeline operators with regard to judging the structural integrity of pipelines. In order to assess the actual mechanical strength of pipelines based on measurement results obtained by inspection pigs, guidance is given for future processing, which eventually can be used as a basis for an industry standard. A literature study of the commercially available types of inspection pigs describes and synoptically lists the respective pros and cons. In essence the report comprises besides check lists of operating data for the pipeline and the pig runs mainly the evaluation of defects and respective calculating procedures. Included are recommendations regarding maintenance planning, verification of defects as well as repetition of pig runs. (orig.) [German] Ziel des Berichtes ist die Erfassung und Dokumentation zum derzeitigen Stand der Technik und des vorhandenen umfangreichen Know-how von Sachverstaendigen und Pipelinebetreibern auf dem Gebiet der sicherheitstechnischen Beurteilung von Pipelines. Fuer den Festigkeitsnachweis von Pipelines aufgrund der Messergebnisse von Pruefmolchen wurde ein Leitfaden als Basis fuer die zukuenftige Vorgehensweise erstellt, der eventuell die Grundlage eines normativen Regelwerkes bilden kann. In einer Literaturstudie wurden die auf dem Markt befindlichen Pruefmolchtypen zusammenfassend beschrieben und ihre Vor- und Nachteile tabellarisch gegenuebergestellt und bewertet. Neben der Erstellung von Checklisten fuer notwendige Daten zum Betrieb der Pipeline und der Molchlaeufe bildet die Fehlerbewertung mit entsprechenden Berechnungsverfahren den Hauptteil dieses Berichtes. Hinweise zur Instandhaltungsplanung (Fehlerverifikation und Molchlaufwiederholung) werden gegeben. (orig.)

  16. 100J-level nanosecond pulsed Yb:YAG cryo-cooled DPSSL amplifier

    Science.gov (United States)

    Smith, J. M.; Butcher, T. J.; Mason, P. D.; Ertel, K.; Phillips, P. J.; Banerjee, S.; De Vido, M.; Chekhlov, O.; Divoky, M.; Pilar, J.; Shaikh, W.; Hooker, C.; Lucianetti, A.; Hernandez Gomez, C.; Mocek, T.; Edwards, C.; Collier, J. L.

    2018-02-01

    We report on the successful demonstration of the world's first kW average power, 100 Joule-class, high-energy, nanosecond pulsed diode-pumped solid-state laser (DPSSL), DiPOLE100. Results from the first long-term test for amplification will be presented; the system was operated for 1 hour with 10 ns duration pulses at 10 Hz pulse repetition rate and an average output energy of 105 J and RMS energy stability of approximately 1%. The laser system is based on scalable cryogenic gas-cooled multi-slab ceramic Yb:YAG amplifier technology. The DiPOLE100 system comprises three major sub-systems, a spatially and temporally shaped front end, a 10 J cryo-amplifier and a 100 J cryo-amplifier. The 10 J cryo-amplifier contain four Yb:YAG ceramic gain media slabs, which are diode pumped from both sides, while a multi-pass architecture configured for seven passes enables 10 J of energy to be extracted at 10 Hz. This seeds the 100 J cryo-amplifier, which contains six Yb:YAG ceramic gain media slabs with the multi-pass configured for four passes. Our future development plans for this architecture will be introduced including closed-loop pulse shaping, increased energy, higher repetition rates and picosecond operation. This laser architecture unlocks the potential for practical applications including new sources for industrial materials processing and high intensity laser matter studies as envisioned for ELI [1], HiLASE [2], and the European XFEL [3]. Alternatively, it can be used as a pump source for higher repetition rate PW-class amplifiers, which can themselves generate high-brightness secondary radiation and ion sources leading to new remote imaging and medical applications.

  17. Ein „neuer" javanischer Fundort von Phrynoglossus laevis laevis ( Gthr.)

    NARCIS (Netherlands)

    Brongersma, L.D.

    1935-01-01

    In der herpetologischen Sammlung, die dem Rijksmuseum van Natuurlijke Historie, Leiden, vor etwa hundert Jahre von Boie und Macklot übersandt wurde, befanden sich zwei Exemplare von Phrynoglossus laevis laevis (Gthr.). Diese Stücke wurden von Van Kampen (1923, p. 232 Fussnote: Oxyglossus laevis) in

  18. Neuro- und Gliotoxizität von Wolframcarbid-basierten Nanopartikeln in vitro

    OpenAIRE

    Bastian, Susanne

    2011-01-01

    Die Anzahl neurodegenerativer Erkrankungen nimmt in unserer Gesellschaft stetig zu. Obwohl inzwischen eine Reihe genetischer Ursachen identifiziert worden sind, wird auch der Einfluss von Umweltfaktoren bei der Pathogenese dieser Erkrankungen zunehmend in Betracht gezogen. Der Beitrag von ultrafeinen Partikeln aus Industrie und Umwelt auf neurodegenerative Erkrankungen steht daher zunehmend im Fokus der Forschung. Die Translokation von ultrafeinen Partikeln bzw. Nanopartikeln ins Gehirn ist b...

  19. Muuga / Mary von Grünewaldt ; tõlk. Mati Sirkel

    Index Scriptorium Estoniae

    Grünewaldt, Mary von

    2004-01-01

    Leo Zoegelt ostetud Muuga mõisahoone korrastamisest ja uue hoone ehitamisest C. T. von Neffi kunstikogu paigutamise tarbeks. Tütre mälestused. Tõlgitud raamatust: Skizzen und Bilder aus dem Leben Carl Timoleon von Neff / Mary von Grünewaldt. Darmstadt, 1887

  20. Die grossen Physiker und ihre Entdeckungen von den fallenden Körpern zu den Quarks

    CERN Document Server

    Segrè, Emilio

    1998-01-01

    Von Galileo Galilei bis zu Richard Feynman und Murray Gell-Mann - von den fallenden Körpern zu den Quarks: Der Physiknobelpreisträger Emilio Segre hat seine ganz persönliche Geschichte der Physik geschrieben. Er erzählt von den großen Gestalten und deren wichtigen Entdeckungen mit großer Anschaulichkeit und Lebendigkeit.