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Sample records for 24mg 44ca 90zr

  1. Pygmy dipole strength in 90Zr

    CERN Document Server

    Schwengner, R; Tsoneva, N; Benouaret, N; Beyer, R; Erhard, M; Grosse, E; Junghans, A R; Klug, J; Kosev, K; Lenske, H; Nair, C; Schilling, K D; Wagner, A

    2008-01-01

    The dipole response of the N=50 nucleus 90Zr was studied in photon-scattering experiments at the electron linear accelerator ELBE with bremsstrahlung produced at kinetic electron energies of 7.9, 9.0, and 13.2 MeV. We identified 189 levels up to an excitation energy of 12.9 MeV. Statistical methods were applied to estimate intensities of inelastic transitions and to correct the intensities of the ground-state transitions for their branching ratios. In this way we derived the photoabsorption cross section up to the neutron-separation energy. This cross section matches well the photoabsorption cross section obtained from (gamma,n) data and thus provides information about the extension of the dipole-strength distribution toward energies below the neutron-separation energy. An enhancement of E1 strength has been found in the range of 6 MeV to 11 MeV. Calculations within the framework of the quasiparticle-phonon model ascribe this strength to a vibration of the excessive neutrons against the N = Z neutron-proton c...

  2. Producing a compound Nucleus via Inelastic Scattering: The 90Zr(alpha,alpha')90Zr* Case

    Energy Technology Data Exchange (ETDEWEB)

    Escher, J E; Dietrich, F S

    2008-05-23

    In a Surrogate reaction a compound nucleus is produced via a direct reaction (pickup, stripping, or inelastic scattering). For a proper application of the Surrogate approach it is necessary to predict the resulting angular momentum and parity distribution in the compound nucleus. A model for determining these distributions is developed for the case of inelastic alpha scattering off a spherical nucleus. The focus is on obtaining a first, simple description of the direct-reaction process that produces the compound nucleus and on providing the basis for a more complete treatment of the problem. The approximations employed in the present description are discussed and the extensions required for a more rigorous treatment of the problem are outlined. To illustrate the formalism, an application to {sup 90}Zr({alpha},{alpha}{prime}){sup 90}Zr* is presented.

  3. Pygmy dipole resonance and dipole polarizability in 90Zr

    Science.gov (United States)

    Iwamoto, C.; Tamii, A.; Utsunomiya, H.; Akimune, H.; Nakada, H.; Shima, T.; Hashimoto, T.; Yamagata, T.; Kawabata, T.; Fujita, Y.; Matsubara, H.; Suzuki, T.; Fujita, H.; Shimbara, Y.; Nagashima, M.; Sakuda, M.; Mori, T.; Izumi, T.; Okamoto, A.; Kondo, T.; Lui, T.-W.; Bilgier, B.; Kozer, H. C.; Hatanaka, K.

    2014-05-01

    Electric dipole (E1) reduced transition probability B(E1) of 90Zr was obtained by the inelastic proton scattering near 0 degrees using a 295 MeV proton beam and multipole decomposition analysis of the angular distribution by the distorted-wave Born approximation with the Hartree-Fock plus random-phase approximation model and inclusion of El Coulomb excitation, and the E1 strength of the pygmy dipole resonance was found in the vicinity of the neutron threshold in the low-energy tail of the giant dipole resonance. Using the data, we plan to determine the precise dipole polarizability αD which is defined as an inversely energy-weighted sum value of the elecrric dipole strength. The dipole polarizability is expected to constrain the symmetry energy term of the neutron matter equation of state. Thus systematical measurement of the dipole polarizability is important.

  4. Pygmy dipole resonance and dipole polarizability in {sup 90}Zr

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, C.; Tamii, A.; Shima, T.; Hashimoto, T.; Suzuki, T.; Fujita, H.; Hatanaka, K. [Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047 (Japan); Utsunomiya, H.; Akimune, H.; Yamagata, T.; Okamoto, A.; Kondo, T. [Department of Physics, Konan University, Okamoto 8-9-1, Higashinada, Kobe 658-8501 (Japan); Nakada, H. [Department of Physics, Graduate School of Science, Chiba University, Yayoi-cho 1-33, Inage, Chiba 263-8522 (Japan); Kawabata, T. [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan); Fujita, Y. [Department of Physics, Osaka University, Toyonaka, Osaka, 560-0043 (Japan); Matsubara, H. [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Shimbara, Y.; Nagashima, M. [Department of Physics, Niigata University, Niigata 950-21-2 (Japan); Sakuda, M.; Mori, T. [Department of Physics, Okayama University, Okayama 900-0082 (Japan); and others

    2014-05-02

    Electric dipole (E1) reduced transition probability B(E1) of {sup 90}Zr was obtained by the inelastic proton scattering near 0 degrees using a 295 MeV proton beam and multipole decomposition analysis of the angular distribution by the distorted-wave Born approximation with the Hartree-Fock plus random-phase approximation model and inclusion of El Coulomb excitation, and the E1 strength of the pygmy dipole resonance was found in the vicinity of the neutron threshold in the low-energy tail of the giant dipole resonance. Using the data, we plan to determine the precise dipole polarizability α{sub D} which is defined as an inversely energy-weighted sum value of the elecrric dipole strength. The dipole polarizability is expected to constrain the symmetry energy term of the neutron matter equation of state. Thus systematical measurement of the dipole polarizability is important.

  5. Finite-size effects in amorphous Fe90Zr10/Al75Zr25 multilayers

    OpenAIRE

    Korelis, P. T.; Jönsson, P. E.; Liebig, A.; Wannberg, H. -E.; Nordblad, P.; Hjörvarsson., B.

    2012-01-01

    The thickness dependence of the magnetic properties of amorphous Fe90Zr10 layers has been explored using Fe90Zr10/Al75Zr25 multilayers. The Al75Zr25 layer thickness is kept at 40 \\AA, while the thickness of the Fe90Zr10 layers is varied between 5 and 20 \\AA. The thickness of the Al75Zr25 layers is sufficiently large to suppress any significant interlayer coupling. Both the Curie temperature and the spontaneous magnetization decrease non-linearly with decreasing thickness of the Fe90Zr10 layer...

  6. High Spin States in ^24Mg

    Science.gov (United States)

    Schwartz, J.; Lister, C. J.; Wuosmaa, A.; Betts, R. R.; Blumenthal, D.; Carpenter, M. P.; Davids, C. N.; Fischer, S. M.; Hackman, G.; Janssens, R. V. F.

    1996-05-01

    The ^12C(^16O,α)^24Mg reaction was used at 51.5MeV to populate high angular momentum states in ^24Mg. Gamma-rays de-exciting high spin states were detected in a 20 detector spectrometer (the AYE-ball) triggered by the ANL Fragment Mass Analyser (FMA). Channel selection, through detection of ^24Mg nuclei with the appropriate time of flight, was excellent. All the known decays from high spin states were seen in a few hours, with the exception of the 5.04 MeV γ-decay of the J^π=9^- state at 16.904 MeV footnote A.E.Smith et al., Phys. Lett. \\underlineB176, (1986)292. which could not be confirmed. The potential of the technique for studying the radiative decay of states with very high spin in light nuclei will be discussed.

  7. Decay of a narrow and high spin {sup 24}Mg + {sup 24}Mg resonance

    Energy Technology Data Exchange (ETDEWEB)

    Salsac, M.-D. [IPHC, Universite Louis Pasteur, CNRS-IN2P3, Strasbourg (France)], E-mail: marie-delphine.salsac@ires.in2p3.fr; Haas, F.; Courtin, S. [IPHC, Universite Louis Pasteur, CNRS-IN2P3, Strasbourg (France); Algora, A. [INR, Debrecen (Hungary); Beck, C. [IPHC, Universite Louis Pasteur, CNRS-IN2P3, Strasbourg (France); Beghini, S. [Universita di Padova and INFN, Padova (Italy); Behera, B.R. [INFN Laboratori Nazionali di Legnaro, Legnaro (Italy); Chapman, R. [University of the West of Scotland, Paisley (United Kingdom); Corradi, L. [INFN Laboratori Nazionali di Legnaro, Legnaro (Italy); Dombradi, Z. [INR, Debrecen (Hungary); Farnea, E. [Universita di Padova and INFN, Padova (Italy); Fioretto, E.; Gadea, A. [INFN Laboratori Nazionali di Legnaro, Legnaro (Italy); Jenkins, D.G. [University of York, York (United Kingdom); Latina, A. [INFN Laboratori Nazionali di Legnaro, Legnaro (Italy); Lebhertz, D. [IPHC, Universite Louis Pasteur, CNRS-IN2P3, Strasbourg (France); Lenzi, S. [Universita di Padova and INFN, Padova (Italy); Liang, X. [University of the West of Scotland, Paisley (United Kingdom); Marginean, N. [INFN Laboratori Nazionali di Legnaro, Legnaro (Italy); Montagnoli, G. [Universita di Padova and INFN, Padova (Italy)] (and others)

    2008-03-01

    The {sup 24}Mg + {sup 24}Mg reaction has been studied at the Legnaro Tandem at a CM bombarding energy of 45.7 MeV where a narrow and high spin resonance has been reported previously. The decay of the resonance into the inelastic and fusion-evaporation channels has been investigated. The ON and OFF resonance decay yields have been measured using, for the inelastic channels, the fragment spectrometer PRISMA and the {gamma} array CLARA, and, for the fusion-evaporation channels, the Si array EUCLIDES and the {gamma} array GASP. Strong resonant effects have been observed in the inelastic channels involving the 2{sub 1}{sup +} and 4{sub 1}{sup +} states of the {sup 24}Mg ground state band. Weaker effects are also seen in certain fusion-evaporation channels. The properties of the studied resonance are in agreement with molecular model predictions. It is also proposed that the narrow and high spin {sup 24}Mg + {sup 24}Mg resonance corresponds to the formation of a fast rotating and highly prolate deformed {sup 48}Cr after a Jacobi shape transition and just before fission.

  8. Vibrational thermodynamics of Fe90Zr7B3 nanocrystalline alloy from nuclear inelastic scattering

    DEFF Research Database (Denmark)

    Stankov, S.; Miglierini, M.; Chumakov, A. I.

    2010-01-01

    Recently we determined the iron-partial density of vibrational states (DOS) of nanocrystalline Fe(90)Zr(7)B(3) (Nanoperm), synthesized by crystallization of an amorphous precursor, for various stages of nanocrystallization separating the DOS of the nanograins from that of the interfaces [S. Stank...

  9. Clustering effects in 48Cr composite nuclei produced via 24Mg + 24Mg reaction

    Directory of Open Access Journals (Sweden)

    Cinausero M.

    2012-02-01

    Full Text Available In the framework of studying clustering effects in N=Z light nuclei, an experiment was carried out to get information on the properties of the 48Cr composite nuclei produced via the 24Mg +24Mg reaction. In particular, the study regards the 48Cr at 60 MeV of excitation energy where a resonance with a narrow width (170 KeV has been found by measuring the elastic and anelastic channels. To determine the deformation of this state, evaporative Light Charged Particles (LCP are measured and compared to the Statistical Model (SM predictions, which are very sensitive to nuclear deformation. The experiment was performed at LNL using the 8ĒLP apparatus to select LCPs and a Parallel Plate Avalanche Counter (PPAC system to detect the Evaporation Residues (ER. Preliminary results on the measurements of ER – LCP and LCP – LCP angular correlations are presented which indicate the presence of a very large deformation.The analysis will proceed with the extraction of the LCP energy spectra and with the angular correlations for high multiplicity channels to determine the deformation.

  10. Exploring the spin states of 90Zr populated by (p,p’, (p,d, and (p,t reactions

    Directory of Open Access Journals (Sweden)

    Ota S.

    2016-01-01

    Full Text Available The 90Zr nucleus was produced by three different reactions: 90Zr(p,p’, 91Zr(p,d, and 92Zr(p,t, and the spin-parity (Jπ population of the 90Zr states produced by these reactions was studied to investigate the surrogate reaction approach, which aims at indirectly determining cross sections for compound-nuclear reactions involving unstable targets such as 89Zr(n,γ. Discrete γ-rays, associated with the de-excitation of 90Zr and 89Zr, were measured in coincidence with light ions at 90Zr excitation energies extending above the neutron separation energy. Low-lying states populated by (p,d and (p,t reactions agreed well with the previous measurements. The measured γ transition systematics were used to gain insights into the Jπ distribution of 90Zr around the neutron separation energy and it was found that the (p,p’ reaction preferentially produces lower J states than (p,d and (p,t reactions in the studied energy region.

  11. Effect of Tensor Correlations on Gamow-Teller States in 90Zr and 208Pb

    CERN Document Server

    Bai, C L; Zhang, H Q; Zhang, X Z; Colò, G; Xu, F R

    2008-01-01

    The tensor terms of the Skyrme effective interaction are included in the self-consistent Hartree-Fock plus Random Phase Approximation (HF+RPA) model. The Gamow-Teller (GT) strength function of 90Zr and 208Pb are calculated with and without the tensor terms. The main peaks are moved downwards by about 2 MeV when including the tensor contribution. About 10% of the non-energy weighted sum rule is shifted to the excitation energy region above 30 MeV by the RPA tensor correlations. The contribution of the tensor terms to the energy weighted sum rule is given analytically, and compared to the outcome of RPA.

  12. Fragmentation of spin-dipole strength in {sup 90}Zr and {sup 208}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Marketin, T., E-mail: marketin@phy.hr [GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstrasse 1, D-64291 Darmstadt (Germany); Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Litvinova, E. [ExtreMe Matter Institute EMMI and Research Division, GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstrasse 1, D-64291 Darmstadt (Germany); Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Ring, P. [Physik-Department der Technischen Universitaet Muenchen, D-85748 Garching (Germany)

    2012-01-05

    An extension of time-dependent covariant density functional theory that includes particle-vibration coupling is applied to the charge-exchange channel. Spin-dipole excitation spectra are calculated an compared to available data for {sup 90}Zr and {sup 208}Pb. A significant fragmentation is found for all three angular-momentum components of the spin-dipole strength as a result of particle-vibration coupling, as well as a shift of a portion of the strength to higher energy. A high-energy tail is formed in the strength distribution that linearly decreases with energy. Using a model-independent sum rule, the corresponding neutron skin thickness is estimated and shown to be consistent with values obtained at the mean-field level.

  13. Gamow-Teller Resonance of 90Zr in a Relativistic Approach

    Institute of Scientific and Technical Information of China (English)

    马中玉; 陈宝秋

    2003-01-01

    We establish the formalism of nuclear spin-isospin excitations, especially the Gamow-Teller resonance in a fully consistent relativistic random-phase approximation. A relativistic form of the Landau-Migdal parameter g′ is adopted as a residual spin-isospin correlation force. In the non-relativistic limit it reproduces the excitation energy of the giant Gamow-Teller resonance state obtained in the non-relativistic model. The Gamow-Teller resonance for finite nuclei is investigated in a relativistic approach for the first time. It is found that the Ikeda sum rule of90Zr is quenched about 8% in the Hartree as well as the correlated strengths due to the poles of the negative Dirac states at energies above 1 GeV.

  14. Total reaction cross sections for {sup 8}Li + {sup 90}Zr at near-barrier energies

    Energy Technology Data Exchange (ETDEWEB)

    Pakou, A.; Aslanoglou, X.; Sgouros, O.; Soukeras, V. [The University of Ioannina, Department of Physics and HINP, Ioannina (Greece); Pierroutsakou, D.; Boiano, A.; Parascandolo, C. [INFN, Sezione di Napoli, Napoli (Italy); Mazzocco, M.; Soramel, F.; Strano, E.; Torresi, D. [Universita di Padova, Dipartimento di Fisica e Astronomia, Padova (Italy); INFN, Sezione di Padova, Padova (Italy); Acosta, L.; Marquinez-Duran, G.; Martel, I. [Universidad de Huelva, Departamento de Fisica Aplicada, Huelva (Spain); Boiano, C. [INFN, Sezione di Milano, Milano (Italy); Carbone, D.; Cavallaro, M. [INFN Laboratori Nazionali del Sud, Catania (Italy); Grebosz, J. [The Henryk Niewodniczanski Institute of Nuclear Physics (IFJ PAN), Krakow (Poland); Keeley, N. [National Center for Nuclear Research, Otwock Warsaw (Poland); La Commara, M. [INFN, Sezione di Napoli, Napoli (Italy); Universita di Napoli ' ' Federico II' ' , Dipartimento di Scienze Fisiche, Napoli (Italy); Manea, C. [INFN, Sezione di Padova, Padova (Italy); Rusek, K.; Trzcinska, A. [University of Warsaw, Heavy Ion Laboratory, Warsaw (Poland); Sanchez-Benitez, A.M. [Centro de Fisica Nuclear da Universidade de Lisboa, Lisboa (Portugal); Signorini, C. [INFN, LNL, Legnaro (Italy); Stiliaris, E. [University of Athens, Institute of Accelerating Systems and Applications and Department of Physics, Athens (Greece); Watanabe, Y.X. [High Energy Accelerator Research Organization (KEK), Institute of Particle and Nuclear Studies (IPNS), Ibaraki (Japan); Yamaguchi, H. [University of Tokyo, Center for Nuclear Study (CNS), Saitama (Japan)

    2015-05-15

    Total reaction cross sections for the radioactive nucleus {sup 8}Li on {sup 90}Zr are reported at the near-barrier energies of 18.5 and 21.5MeV, derived from quasi-elastic scattering measurements. An analysis of the quasi-elastic scattering results is performed within an optical model framework using the BDM3Y1 interaction and total reaction cross sections are deduced. These quantities, appropriately reduced, are compared with previous data obtained in elastic scattering measurements with well and weakly bound projectiles on various targets and a formula for predicting total reaction cross sections with an uncertainty of ∝ 20 % is obtained. Further on, the ratios of direct to total reaction cross sections are estimated for {sup 6,8}Li on various targets and are compared with CDCC or CRC calculations. The energy dependence of the optical potential is also discussed. (orig.)

  15. Total reaction cross sections for 8Li + 90Zr at near-barrier energies

    Science.gov (United States)

    Pakou, A.; Pierroutsakou, D.; Mazzocco, M.; Acosta, L.; Aslanoglou, X.; Boiano, A.; Boiano, C.; Carbone, D.; Cavallaro, M.; Grebosz, J.; Keeley, N.; La Commara, M.; Manea, C.; Marquinez-Duran, G.; Martel, I.; Parascandolo, C.; Rusek, K.; Sánchez-Benítez, A. M.; Sgouros, O.; Signorini, C.; Soramel, F.; Soukeras, V.; Stiliaris, E.; Strano, E.; Torresi, D.; Trzcinska, A.; Watanabe, Y. X.; Yamaguchi, H.

    2015-05-01

    Total reaction cross sections for the radioactive nucleus 8Li on 90Zr are reported at the near-barrier energies of 18.5 and 21.5MeV, derived from quasi-elastic scattering measurements. An analysis of the quasi-elastic scattering results is performed within an optical model framework using the BDM3Y1 interaction and total reaction cross sections are deduced. These quantities, appropriately reduced, are compared with previous data obtained in elastic scattering measurements with well and weakly bound projectiles on various targets and a formula for predicting total reaction cross sections with an uncertainty of % is obtained. Further on, the ratios of direct to total reaction cross sections are estimated for 6,8Li on various targets and are compared with CDCC or CRC calculations. The energy dependence of the optical potential is also discussed.

  16. Preparation of 24Mg-Fe-Cu Target

    Institute of Scientific and Technical Information of China (English)

    FAN; Qi-wen; DU; Ying-hui; ZHANG; Rong

    2012-01-01

    <正>The three-layer-sandwich targets of 24Mg-Fe-Cu needed to be prepared in the physics experiment. The middle layers are thin ferromagnetic Fe layers of about 3.2 mg/cm2. The recoil stopper layers are thick crystallized and defect-free Cu layers of about 15 mg/cm2. The thickness of the 24Mg target layers is about 300 μg/cm2, and the uniformity should be better than 90%.

  17. Important influence of single neutron stripping coupling on near-barrier 8Li + 90Zr quasi-elastic scattering

    Science.gov (United States)

    Pakou, A.; Keeley, N.; Pierroutsakou, D.; Mazzocco, M.; Acosta, L.; Aslanoglou, X.; Boiano, A.; Boiano, C.; Carbone, D.; Cavallaro, M.; Grebosz, J.; La Commara, M.; Manea, C.; Marquinez-Duran, G.; Martel, I.; Parascandolo, C.; Rusek, K.; Sánchez-Benítez, A. M.; Sgouros, O.; Signorini, C.; Soramel, F.; Soukeras, V.; Stiliaris, E.; Strano, E.; Torresi, D.; Trzcińska, A.; Watanabe, Y. X.; Yamaguchi, H.

    2015-07-01

    Quasi-elastic scattering data were obtained for the radioactive nucleus 8Li on a 90Zr target at the near-barrier energy of 18.5MeV over the angular range to 80°. They were analyzed within the coupled channels and coupled reaction channels frameworks pointing to a strong coupling effect for single neutron stripping, in contrast to 6, 7 Li + 90 Zr elastic scattering at similar energies, a non-trivial result linked to detailed differences in the structure of these Li isotopes.

  18. Domain structures of nanocrystalline Fe90Zr7B3 alloy studied by Lorentz microscopy

    Directory of Open Access Journals (Sweden)

    Youhui Gao, Daisuke Shindo, Teruo Bitoh and Akihiro Makino

    2003-01-01

    Full Text Available As-quenched Fe90Zr7B3 alloy has been crystallized at 773, 923 and 973 K, it is found that the specimens annealed at 773 and 923 K have grains with the same size, but the one annealed at 773 K has a thick amorphous matrix and a broad grain size distribution. Big domains and smooth domain walls are observed in the specimen annealed at the optimum condition (923 K, and excellent magnetic softness is obtained. On the other hand, the one annealed at 973 K has very large grains (40 nm. Very small domains with irregular walls are observed, indicating a weak intergranular exchange coupling.Through in situ Lorentz microscopy, a relaxation of internal stress in the specimen annealed at 773 K is observed at an elevated temperature (333 K. The internal stress observed is considered to be one of the important factors that degrade the soft magnetic properties. Based on the results of differential thermal analysis, a two-step annealing, where the as-quenched specimen is pre-heated at 723 K and subsequently annealed at 773 K, is utilized. The domain structure of the specimen treated by the two-step annealing is analyzed. It is found that the size of the domain is larger than that of the specimen annealed at 773 K, suggesting the possibility of control of the soft magnetic properties.

  19. Neutron capture cross section of $^{90}$Zr Bottleneck in the s-process reaction flow

    CERN Document Server

    Tagliente, G; Milazzo, P M; Moreau, C; Aerts, G; Abbondanno, U; Alvarez, H; Alvarez-Velarde, F; Andriamonje, Samuel A; Andrzejewski, J; Assimakopoulos, Panayiotis; Audouin, L; Badurek, G; Baumann, P; Bečvář, F; Berthoumieux, E; Bisterzo, S; Calviño, F; Calviani, M; Cano-Ott, D; Capote, R; Carrapiço, C; Cennini, P; Chepel, V; Chiaveri, Enrico; Colonna, N; Cortés, G; Couture, A; Cox, J; Dahlfors, M; David, S; Dillman, I; Domingo-Pardo, C; Dridi, W; Durán, I; Eleftheriadis, C; Embid-Segura, M; Ferrant, L; Ferrari, A; Ferreira-Marques, R; Furman, W; Gallino, R; Gonçalves, I; Gonzalez-Romero, E; Gramegna, F; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martínez, A; Igashira, M; Jericha, E; Käppeler, F; Kadi, Y; Karadimos, D; Karamanis, D; Kerveno, M; Köhler, P; Kossionides, E; Krtička, M; Lamboudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marrone, S; Martínez, T; Massimi, C; Mastinu, P; Mengoni, A; Mosconi, M; Neves, F; Oberhummer, Heinz; O'Brien, S; Pancin, J; Papachristodoulou, C; Papadopoulos, C; Paradela, C; Patronis, N; Pavlik, A; Pavlopoulos, P; Perrot, L; Pigni, M T; Plag, R; Plompen, A; Plukis, A; Poch, A; Praena, J; Pretel, C; Quesada, J; Rauscher, T; Reifarth, R; Rubbia, Carlo; Rudolf, G; Rullhusen, P; Salgado, J; Santos, J; Sarchiapone, L; Savvidis, I; Stéphan, C; Taín, J L; Tassan-Got, L; Tavora, L; Terlizzi, R; Vannini, G; Vaz, P; Ventura, A; Villamarín, D; Vincente, M, C; Vlachoudis, V; Vlastou, R; Voss, F; Walter, S; Wendler, H; Wiescher, M; Wisshak, K

    2008-01-01

    The neutron capture cross sections of the Zr isotopes have important implications in nuclear astrophysics and for reactor design. The small cross section of the neutron magic nucleus 90Zr, which accounts for more than 50% of natural zirconium represents one of the key isotopes for the stellar s-process, because it acts as a bottleneck in the neutron capture chain between the Fe seed and the heavier isotopes. The same element, Zr, also is an important component of the structural materials used in traditional and advanced nuclear reactors. The (n,γ) cross section has been measured at CERN, using the n_TOF spallation neutron source. In total, 45 resonances could be resolved in the neutron energy range below 70 keV, 10 being observed for the first time thanks to the high resolution and low backgrounds at n_TOF. On average, the Γγ widths obtained in resonance analyses with the R-matrix code SAMMY were 15% smaller than reported previously. By these results, the accuracy of the Maxwellian averaged cross section f...

  20. 1- and 2+ discrete states in 90Zr populated via the (17O,'17Oγ ) reaction

    Science.gov (United States)

    Crespi, F. C. L.; Bracco, A.; Nicolini, R.; Lanza, E. G.; Vitturi, A.; Mengoni, D.; Leoni, S.; Benzoni, G.; Blasi, N.; Boiano, C.; Bottoni, S.; Brambilla, S.; Camera, F.; Corsi, A.; Giaz, A.; Million, B.; Pellegri, L.; Vandone, V.; Wieland, O.; Bednarczyk, P.; Ciemała, M.; Kmiecik, M.; Krzysiek, M.; Maj, A.; Bazzacco, D.; Bellato, M.; Birkenbach, B.; Bortolato, D.; Calore, E.; Cederwall, B.; de Angelis, G.; Désesquelles, P.; Eberth, J.; Farnea, E.; Gadea, A.; Görgen, A.; Gottardo, A.; Hess, H.; Isocrate, R.; Jolie, J.; Jungclaus, A.; Kempley, R. S.; Labiche, M.; Menegazzo, R.; Michelagnoli, C.; Molini, P.; Napoli, D. R.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Sahin, E.; Siem, S.; Söderström, P.-A.; Stezowski, O.; Theisen, Ch.; Ur, C.; Valiente-Dobón, J. J.

    2015-02-01

    2+ and 1- states in 90Zr were populated via the (17O,'17Oγ ) reaction at 340 MeV. The γ decay was measured with high resolution using the AGATA (advanced γ tracking array demonstrator array). Differential cross sections were obtained at few different angles for the scattered particle. The results of the elastic scattering and inelastic excitation of 2+,3-, and 1- states are compared with distorted-wave Born approximation (DWBA) calculations, using both the standard collective form factor and a form factor obtained by folding microscopically calculated transition densities. This allowed to extract the isoscalar component of the 1- state at 6.424 MeV. The comparison of the present (17O,'17Oγ ) data with existing (γ ,γ' ) and (p ,p' ) data in the corresponding region of the γ continuum (6-11 MeV), characterized by a large E 1 component, shows completely different behaviors of the cross section as a function of the nuclear excitation energy. The comparison of the data with DWBA calculations suggests a decrease of the isoscalar strength in the cross section with increasing excitation energy.

  1. Alpha-particle decays from excited states in 24Mg

    Institute of Scientific and Technical Information of China (English)

    LIOTTA; R; J

    2011-01-01

    Using a cluster model based on the Woods-Saxon potential, alpha-particle decays from excited states in 24Mg have been system atically investigated. Calculations can in general reproduce experimental data, noticing the fact that the preformation factor P of alpha particle in alpha-decaying nuclei is of order from 100 to 10?2. This can be the evidence for the α+20Ne structure in 24Mg. Meanwhile, the results also show the existence of other configurations, such as 16O+2α. Since the calculated decay widths are very sensitive to the angular momentum carried by the outgoing cluster (α particle), our results could serve as a guide to experimental spin assignments.

  2. Multiplicity characteristics in relativistic 24Mg-nucleus collisions

    Institute of Scientific and Technical Information of China (English)

    A.Abdelsalam; E.A.Shaat; Z.Abou-Moussa; B.M.Badawy; Z.S.Mater

    2013-01-01

    This work is concerned with the analyses of the shower and gray particle production in 4.5 A GeV/c 24Mg collision with emulsion nuclei.The highest particle production occurs in the region of the low impact parameters.While the multiplicity of the shower particles emitted in the forward direction depends on the projectile mass number and energy,the multiplicity of the backward ones shows a limiting behaviour.The source of the emission of the forward shower particles is completely different from that of the backward ones.The target fragments are produced in a thermalized system of emission.

  3. A study of the 90Zr( 3He, t) reaction at 43.4 MeV

    Science.gov (United States)

    Fields, C. A.; Ristinen, R. A.; Samuelson, L. E.; Smith, P. A.

    1982-09-01

    Low-lying states of 90Nb have been investigated using the 90Zr( 3He, t) reaction at 43.4 MeV. In addition to the well-known π( P{1}/{2}) v (g {9}/{2}) -1and π(g {9}/{2}) v (g {9}/{2}) -1 particle-hole states, many other levels were observed. The angular distributions for the ( g{9}/{2}) 2 states are investigated using DWBA calculations using collective, OPEP, and independent tensor and spin-isospin potentials.

  4. Nuclear Structure of the Closed Subshell Nucleus 90Zr Studied with the (n,n'(gamma)) Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, P E; Younes, Y; Becker, J A; Bernstein, L A; Baum, E M; DiPrete, D P; Gatenby, R A; Johnson, E L; McGrath, C A; Yates, S W; Devlin, M; Fotiades, N; Nelson, R O; Brown, B A

    2003-06-12

    States in {sup 90}Zr have been observed with the (n,n{prime}{gamma}) reaction using both spallation and monoenergetic accelerator-produced neutrons. A scheme comprised of 81 levels and 157 transitions was constructed concentrating on levels below 5.6 MeV in excitation energy. Spins have been determined by considering data from all experimental studies performed for {sup 90}Zr. Lifetimes have been deduced using the Doppler-shift attenuation method for many of the states and transition rates have been obtained. A spherical shell-model interpretation in terms of particle-hole excitations assuming a {sup 88}Sr closed core is given. In some cases, enhancements in B(M1) and B(E2) values are observed that cannot be explained by assuming simple particle-hole excitations. Shell-model calculations using an extended f pg-shell model space reproduce the spectrum of excited states very well, and the gross features of the B(M1) and B(E2) transition rates. Transition rates for individual levels show discrepancies between calculations and experimental values.

  5. Important influence of single neutron stripping coupling on near-barrier {sup 8}Li + {sup 90}Zr quasi-elastic scattering

    Energy Technology Data Exchange (ETDEWEB)

    Pakou, A.; Aslanoglou, X.; Sgouros, O.; Soukeras, V. [The University of Ioannina, Department of Physics and HINP, Ioannina (Greece); Keeley, N. [National Centre for Nuclear Research, Otwock (Poland); Pierroutsakou, D.; Boiano, A.; Parascandolo, C. [INFN, Napoli (Italy); Mazzocco, M.; Soramel, F.; Strano, E.; Torresi, D. [Universita di Padova, Dipartimento di Fisica e Astronomia, Padova (Italy); INFN, Padova (Italy); Acosta, L. [Universidad Nacional Autonoma de Mexico, Instituto de Fisica, Mexico (Mexico); INFN, Catania (Italy); Boiano, C. [INFN, Milano (Italy); Carbone, D.; Cavallaro, M. [INFN Laboratori Nazionali del Sud, Catania (Italy); Grebosz, J. [The Henryk Niewodniczanski Institute of Nuclear Physics (IFJ PAN), Krakow (Poland); La Commara, M. [INFN, Napoli (Italy); Universita di Napoli ' ' Federico II' ' , Dipartimento di Scienze Fisiche, Napoli (Italy); Manea, C. [INFN, Padova (Italy); Marquinez-Duran, G.; Martel, I. [Universidad de Huelva, Departamento de Fisica Aplicada, Huelva (Spain); Rusek, K.; Trzcinska, A. [University of Warsaw, Heavy Ion Laboratory, Warsaw (Poland); Sanchez-Benitez, A.M. [Centro de Fisica Nuclear da Universidade de Lisboa, Lisboa (Portugal); Signorini, C. [LNL, INFN, Legnaro (Italy); Stiliaris, E. [University of Athens, Institute of Accelerating Systems and Applications and Department of Physics, Athens (Greece); Watanabe, Y.X. [High Energy Accelerator Research Organization (KEK), Institute of Particle and Nuclear Studies (IPNS), Ibaraki (Japan); Yamaguchi, H. [University of Tokyo, RIKEN campus, Center for Nuclear Study (CNS), Saitama (Japan)

    2015-07-15

    Quasi-elastic scattering data were obtained for the radioactive nucleus {sup 8}Li on a {sup 90}Zr target at the near-barrier energy of 18.5 MeV over the angular range θ{sub lab} = 15 {sup circle} to 80 . They were analyzed within the coupled channels and coupled reaction channels frameworks pointing to a strong coupling effect for single neutron stripping, in contrast to {sup 6,} {sup 7}Li + {sup 90}Zr elastic scattering at similar energies, a non-trivial result linked to detailed differences in the structure of these Li isotopes. (orig.)

  6. Reaction cross sections for protons on {sup 12}C, {sup 40}Ca, {sup 90}Zr and {sup 208}Pb at energies between 80 and 180 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Auce, A.; Ingemarsson, A.; Johansson, R. [and others

    2005-04-01

    Results of reaction cross section measurements on {sup 12}C, {sup 40}Ca, {sup 90}Zr and {sup 208}Pb at incident proton energies between 80 and 180 MeV and for {sup 58}Ni at 81 MeV are presented. The experimental procedure is described and the results are compared with earlier measurements and predictions using macroscopic and microscopic models.

  7. 87Y(n,γ and 89,90Zr(n,γ cross sections from a surrogate reaction approach

    Directory of Open Access Journals (Sweden)

    Ota Shuya

    2015-01-01

    Full Text Available The surrogate reaction approach is an indirect method for determining nuclear reaction cross sections which cannot be measured directly or predicted reliably. While recent studies demonstrated the validity of the surrogate reaction approach for studying fission cross sections for short-lived actinides, its applicability for radiative neutron capture reactions ((n,γ is still under investigation. We studied the γ decay of excited 88Y and 90,91Zr nuclei produced by 89Y(p,d, 91Zr(p,d, and 92Zr(p,d reactions, respectively, in order to infer the 87Y(n,γ and 89, 90Zr(n,γ cross sections. The experiments were carried out at the K150 Cyclotron facility at Texas A&M University with a 28.5-MeV proton beam. The reaction deuterons were measured at forward angles of 25-60° with the array of three segmented Micron S2 silicon detectors. The compound nuclei with energies up to a few MeV above the neutron separation thresholds were populated. The coincident γ-rays were measured with the array of five Compton-suppressed HPGe clover detectors.

  8. Relevance of single-particle and collective excitations in zirconium isotopes populated by neutron transfer reactions in the {sup 90}Zr+{sup 208}Pb system

    Energy Technology Data Exchange (ETDEWEB)

    Pajtler, M. Varga, E-mail: maja.varga@fizika.unios.hr [Department of Physics, University of Osijek, Trg Ljudevita Gaja 6, 31000 Osijek (Croatia); Szilner, S.; Malenica, D. Jelavić; Mijatović, T.; Soić, N. [Ruer Bošković Institute, HR-10001, Zagreb (Croatia); Corradi, L.; Angelis, G. de; Fioretto, E.; Montanari, D.; Stefanini, A. M.; Valiente-Dobón, J. J. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro (Italy); Gadea, A. [IFIC, CSIC-Universidad de Valencia, E-46071 Valencia (Spain); Haas, F. [Institut Pluridisciplinaire Hubert Curien, CNRS-IN2P3 and Université de Strasbourg, F-67037 Strasbourg (France); Lunardi, S.; Mengoni, D.; Montagnoli, G.; Recchia, F.; Scarlassara, F. [Dipartimento di Fisica, Universitá di Padova, and Istituto Nazionale di Fisica Nucleare, I-35131 Padova (Italy); Märginean, N. [Horia Hulubei National Institute of Physics and Nuclear Engineering, RO-077125 Bucharest-Magurele (Romania); Pollarolo, G. [Dipartimento di Fisica Teorica, Universitá di Torino,and Istituto Nazionale di Fisica Nucleare, I-10125 Torino (Italy); and others

    2015-10-15

    Multineutron transfer reaction {sup 90}Zr+{sup 208}Pb has been studied at the energy close to the Coulomb barrier energy by using the PRISMA + CLARA set-up. In this fragment-γ coincidence measurement, the selective properties of the reaction mechanism in the population of the specific states have been discussed. Based on the observed γ transitions of neutron transfer channels, namely {sup 89–94}Zr isotopes, their level schemes have been constructed and updated.

  9. Emission of β+ Particles Via Internal Pair Production in the 0+ – 0+ Transition of 90Zr: Historical Background and Current Applications in Nuclear Medicine Imaging

    Directory of Open Access Journals (Sweden)

    Marco D'Arienzo

    2013-03-01

    Full Text Available 90Y is traditionally considered as a pure β– emitter. However, the decay of this radionuclide has a minor branch to the 0+ first excited state of 90Zr at 1.76 MeV, that is followed by a β+/β– emission. This internal pair production has been largely studied in the past because it is generated by a rare electric monopole transition (E0 between the states 0+/0+ of 90Zr. The positronic emission has been recently exploited for nuclear medicine applications, i.e. positron emission tomography (PET acquisitions of 90Y-labelled radiopharmaceuticals, widely used as therapeutic agents in internal radiation therapy. To date, this topic is gaining increasing interest in the radiation dosimetry community, as the possibility of detecting β+ emissions from 90Y by PET scanners may pave the way for an accurate patient-specific dosimetry. This could lead to an explosion in scientific production in this field. In the present paper the historical background behind the study of the internal pair production of the 0+/0+ transition of 90Zr is presented along with most up to date measured branch ratio values. An overview of most recent studies that exploit β+ particles emitted from 90Y for PET acquisitions is also provided.

  10. Experimental constraints on the γ-ray strength function in 90Zr using partial cross sections of the Y89(p,γZr90 reaction

    Directory of Open Access Journals (Sweden)

    L. Netterdon

    2015-05-01

    Full Text Available Partial cross sections of the Y89(p,γZr90 reaction have been measured to investigate the γ-ray strength function in the neutron–magic nucleus 90Zr. For five proton energies between Ep=3.65 MeV and Ep=4.70 MeV, partial cross sections for the population of seven discrete states in 90Zr have been determined by means of in-beam γ-ray spectroscopy. Since these γ-ray transitions are dominantly of E1 character, the present measurement allows an access to the low-lying dipole strength in 90Zr. A γ-ray strength function based on the experimental data could be extracted, which is used to describe the total and partial cross sections of this reaction by Hauser–Feshbach calculations successfully. Significant differences with respect to previously measured strength functions from photoabsorption data point towards deviations from the Brink–Axel hypothesis relating the photo-excitation and de-excitation strength functions.

  11. Search for $^{12}$C+$^{12}$C clustering in $^{24}$Mg ground state

    Indian Academy of Sciences (India)

    B N JOSHI; ARUN K JAIN; D C BISWAS; B V JOHN; Y K GUPTA; L S DANU; R P VIND; G K PRAJAPATI; S MUKHOPADHYAY; A SAXENA

    2017-02-01

    In the backdrop of many models, the heavy cluster structure of the ground state of $^{24}$Mg has been probed experimentally for the first time using the heavy cluster knockout reaction $^{24}$Mg($^{12}$C, $^{212}$C)$^{12}$C in thequasifree scattering kinematic domain. In the ($^{12}$C, $^{212}$C) reaction, the direct $^{12}$C-knockout cross-section was found to be very small. Finite-range knockout theory predictions were much larger for ($^{12}$C, 212C) reaction,indicating a very small $^{12}$C−$^{12}$C clustering in $^{24}$Mg(g.s.). Our present results contradict most of the proposed heavy cluster ($^{12}$C+$^{12}$C) structure models for the ground state of $^{24}$Mg.

  12. Spin decomposition of the responses of sup 44 Ca and sup 48 Ca to 300 MeV protons

    Energy Technology Data Exchange (ETDEWEB)

    Baker, F.T.; Bimbot, L.; Fergerson, R.W.; Glashausser, C.; Green, A.; Haeusser, O.; Hicks, K.; Jones, K.; Miller, C.A.; Vetterli, M.; Abegg, R.; Beatty, D.; Bonin, B.; Castel, B.; Chen, X.Y.; Cupps, V.; Djalali, C.; Henderson, R.; Jackson, K.P.; Jeppesen, R.; Nakayama, K.; Nanda, S.K.; Sawafta, R.; Yen, S. (University of Georgia, Athens, Georgia 30602 (US) Institut de Physique Nucleaire, F-91406 Orsay, France Rutgers University, Piscataway, New Jersey 08854 Simon Fraser University, Burnaby, Canada V5A1S6 TRIUMF, 4004 Westbrook Mall, Vancouver, Canada V6T2A3 Los Alamos National Laboratory, Los Alamos, New Mexico 87544 Centre d' Etudes Nucleaires de Saclay, 91191 Gif sur Yvette, CEDEX, France Queen' s University, Kingston, Canada K7L3N6 University of Colorado, Boulder, Colorado 80309 University of South Carolina, Columbia, South Carolina 29208 Continuous Electron Beam Accelerator Facility, 12000 Jefferson Ave., Newport News, Virginia 23606 University of Alberta, Edmonton, Canada T6G2J1)

    1991-07-01

    Angular distributions of the double-differential cross section {ital d}{sup 2}{sigma}/{ital d}{Omega} {ital dE}({sigma}) and the spin-flip probability {ital S}{sub {ital n}{ital n}} have been measured for inclusive proton inelastic scattering from {sup 44}Ca at 290 MeV and from {sup 48}Ca at 318 MeV. Excitation energies up to about 50 MeV for {sup 44}Ca and 40 MeV for {sup 48}Ca have been investigated over the laboratory angular ranges of 3{degree} to 12{degree} for {sup 44}Ca and 3{degree} to 9{degree} for {sup 48}Ca. Multipole decompositions of angular distributions of both the spin-flip cross section {sigma}{ital S}{sub {ital n}{ital n}} and the estimated cross section for {Delta}{ital S}=0 transitions have been performed. Distributions of strengths were deduced for {Delta}{ital L}=1, {Delta}{ital S}=0 (the giant dipole), {Delta}{ital L}=2, {Delta}{ital S}=0 (the giant quadrupole), {Delta}{ital L}=0, {Delta}{ital S}=1 (the magnetic dipole), {Delta}{ital L}=1, {Delta}{ital S}=1 (the spin dipole), and {Delta}{ital L}=2, {Delta}{ital S}=1 (the spin quadrupole). The {Delta}{ital S}=0 summed strengths for {sup 44}Ca are lower than for {sup 40}Ca and {sup 48}Ca. The spin-dipole summed strengths are found to be approximately independent of {ital A}. For {sup 48}Ca, essentially all {ital M}1 strength observed was in the 10.23 MeV 1{sup +} state; for {sup 44}Ca, {ital M}1 strength was observed to be fragmented over a range of 7 to 18 Mev.

  13. Selective properties of neutron transfer reactions in the {sup 90}Zr + {sup 208}Pb system for the population of excited states in zirconium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Varga Pajtler, M., E-mail: mvarga@fizika.unios.hr [Department of Physics, University of Osijek, HR-31000 Osijek (Croatia); Szilner, S. [Rudjer Bošković Institute, HR-10001 Zagreb (Croatia); Corradi, L.; Angelis, G. de; Fioretto, E. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro (Italy); Gadea, A. [IFIC, CSIC-Universidad de Valencia, E-46071 Valencia (Spain); Haas, F. [Institut Pluridisciplinaire Hubert Curien, CNRS-IN2P3 and Université de Strasbourg, F-67037 Strasbourg (France); Lunardi, S. [Dipartimento di Fisica, Universitá di Padova, and Istituto Nazionale di Fisica Nucleare, I-35131 Padova (Italy); Jelavić Malenica, D. [Rudjer Bošković Institute, HR-10001 Zagreb (Croatia); Mărginean, N. [Horia Hulubei National Institute of Physics and Nuclear Engineering, RO-077125 Bucharest-Magurele (Romania); Mengoni, D. [Dipartimento di Fisica, Universitá di Padova, and Istituto Nazionale di Fisica Nucleare, I-35131 Padova (Italy); Mijatović, T. [Rudjer Bošković Institute, HR-10001 Zagreb (Croatia); Montagnoli, G. [Dipartimento di Fisica, Universitá di Padova, and Istituto Nazionale di Fisica Nucleare, I-35131 Padova (Italy); Montanari, D. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro (Italy); Pollarolo, G. [Dipartimento di Fisica Teorica, Universitá di Torino, and Istituto Nazionale di Fisica Nucleare, I-10125 Torino (Italy); and others

    2015-09-15

    Nuclei produced via multineutron transfer channels have been studied in {sup 90}Zr + {sup 208}Pb close to the Coulomb barrier energy in a fragment-γ coincident measurement employing the PRISMA magnetic spectrometer coupled to the CLARA γ-array. The selective properties of the reaction mechanism have been discussed in terms of states and their strength excited in the neutron transfer channels leading to {sup 89–94}Zr isotopes. A strong population of yrast states, with energies up to ∼7.5 MeV has been observed.

  14. Selective properties of neutron transfer reactions in the 90Zr + 208Pb system for the population of excited states in zirconium isotopes

    Science.gov (United States)

    Varga Pajtler, M.; Szilner, S.; Corradi, L.; de Angelis, G.; Fioretto, E.; Gadea, A.; Haas, F.; Lunardi, S.; Jelavić Malenica, D.; Mărginean, N.; Mengoni, D.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Pollarolo, G.; Recchia, F.; Salsac, M.-D.; Scarlassara, F.; Soić, N.; Stefanini, A. M.; Ur, C. A.; Valiente-Dobón, J. J.

    2015-09-01

    Nuclei produced via multineutron transfer channels have been studied in 90Zr + 208Pb close to the Coulomb barrier energy in a fragment-γ coincident measurement employing the PRISMA magnetic spectrometer coupled to the CLARA γ-array. The selective properties of the reaction mechanism have been discussed in terms of states and their strength excited in the neutron transfer channels leading to 89-94Zr isotopes. A strong population of yrast states, with energies up to ∼7.5 MeV has been observed.

  15. Isomeric yield ratios of the {sup 90}Zr({gamma},n){sup 88m,g}Zr reaction up the giant dipole resonance

    Energy Technology Data Exchange (ETDEWEB)

    Bodrov, I.V.; Davydov, M.G.; Rakhmanov, I.B. [Rostov State Univ., Rostov-na-Donu (Russian Federation)] [and others

    1994-08-01

    The isomeric yield ratios Y{sub m}/Y{sub g} of the {sup 90}Zr({gamma},n){sup 88m,g}Zr reaction are measured in the energy range from 13 to 21 MeV with a step of 0.5 MeV. The experimental isomeric ratios are compared with the data obtained by other authors and with the results of theoretical calculations based on the statistical theory and on the model of {open_quotes}semidirect{close_quotes} decay of the giant dipole resonance. 30 refs., 1 fig., 2 tabs.

  16. Pion-nucleus elastic scattering on $^{12}C$, $^{40}Ca$, $^{90}Zr$, and $^{208}Pb$ at 400 and 500 MeV

    CERN Document Server

    Kahrimanis, G; Chen, C M; Clark, B C; Dhuga, K S; Ernst, D J; Faucett, J A; Fortune, H T; Hama, S; Hussein, A; Jiang, M F; Johnson, K W; Kerr, L K; Mathews, S; McGill, J A; Moore, C F; Mordechai, S; Morris, C L; O'Donnell, J; Snell, M; Rawool-Sullivan, M; Ray, L; Whitley, C; Williams, A L; Kahrimanis, George; Burleson, George; Dhuga, Kalvir; Hussein, Ahmed; Mathews, Scott; Gill, John Mc; Mordechai, Shaul; Morris, Christopher L.; Donnell, John O'; Snell, Mike; Rawool-Sullivan, Mohini; Whitley, Charles; Williams, Allen L.

    1997-01-01

    Pion-nucleus elastic scattering at energies above the Delta(1232) resonance is studied using both pi+ and pi- beams on 12C, 40Ca, 90Zr, and 208Pb. The present data provide an opportunity to study the interaction of pions with nuclei at energies where second-order corrections to impulse approximation calculations should be small. The results are compared with other data sets at similar energies, and with four different first-order impulse approximation calculations. Significant disagreement exists between the calculations and the data from this experiment.

  17. $^{24}$Mg($p$, $\\alpha$)$^{21}$Na reaction study for spectroscopy of $^{21}$Na

    CERN Document Server

    Cha, S M; Kim, A; Lee, E J; Ahn, S; Bardayan, D W; Chipps, K A; Cizewski, J A; Howard, M E; Manning, B; O'Malley, P D; Ratkiewicz, A; Strauss, S; Kozub, R L; Matos, M; Pain, S D; Pittman, S T; Smith, M S; Peters, W A

    2015-01-01

    The $^{24}$Mg($p$, $\\alpha$)$^{21}$Na reaction was measured at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory in order to better constrain spins and parities of energy levels in $^{21}$Na for the astrophysically important $^{17}$F($\\alpha, p$)$^{20}$Ne reaction rate calculation. 31 MeV proton beams from the 25-MV tandem accelerator and enriched $^{24}$Mg solid targets were used. Recoiling $^{4}$He particles from the $^{24}$Mg($p$, $\\alpha$)$^{21}$Na reaction were detected by a highly segmented silicon detector array which measured the yields of $^{4}$He particles over a range of angles simultaneously. A new level at 6661 $\\pm$ 5 keV was observed in the present work. The extracted angular distributions for the first four levels of $^{21}$Na and Distorted Wave Born Approximation (DWBA) calculations were compared to verify and extract angular momentum transfer.

  18. δ44Ca in N. pachy (left): A Promising Tool for SST-Reconstruction in High-Latitude Oceans

    Science.gov (United States)

    Hippler, D.; Gussone, N.; Darling, K.; Eisenhauer, A.; Nagler, T. F.

    2002-12-01

    Reconstructions of sea surface temperatures (SSTs) by means of planktonic foraminifera are an essential tool in paleoceanography. Unlike to marine tropical environments where a number of established SST-proxies exist, information on paleo-SST of polar water masses is scarce. In these regions high-resolution records exist mainly for continental environments. Ca isotopes bear a high potential as SST proxies as they are insensitive to changes in global ice volume, evaporation or freshwater input. Here, measurements of the Ca-isotopic composition on calcite shells of Neogloboquadrina pachyderma (left coiling) -a dominant species in subpolar and polar surface waters- are presented. The genotype of individuals tests was determined at the University of Edinburgh. Subsequently the respective calcite shells were analysed for δ44Ca at the University of Bern. The most complete data set is from the polar North Atlantic. All samples are from the same genotype and span a temperature (T) range from 1.9°C to 6.5°C. It was found that T correlates well with δ44Ca. The total δ44Ca-variation results in a δ44Ca-change of 0.2‰ per 1°C defined by a linear regression. In order to test whether the correlation is influenced by hydrographic or genotype differences a second set of a Southern Atlantic genotype of N. pachy (left) has been investigated. Preliminary observations point to T as the main factor controlling δ44Ca variations and a T dependence very similar to that of Arctic specimen. Remarkably, this T dependence (although not the absolute values) is identical within errors to the one of tropical G. sacculifer (Nagler et al., 2000, G3). Thus, even though Ca isotope fractionation is known to be species-dependent, the increase of 0.2‰ δ44Ca per 1°C seems to reflect a particular mode of biocalcification. While more calibration work is needed, it appears that T changes of polar surface waters will be quantitatively resolvable.

  19. NUCLEAR PHYSICS Resonances-Excitation Calculation Studies Investigation of Δ(3, 3) in Ground State of 90Zr Cold Finite Heavy Nucleus at Equilibrium and Under Large Compression

    Science.gov (United States)

    Mohammed, H. E. Abu-Sei'leek

    2011-01-01

    A non-relativistic microscopic mean field theory of finite nuclei is investigated where the nucleus is described as a collection of nucleons and delta resonances. The ground state properties of 90Zr nucleus have been investigated at equilibrium and large amplitude compression using a realistic effective baryon-baryon Hamiltonian based on Reid Soft Core (RSC) potential. The sensitivity of the ground state properties is studied, such as binding energy, nuclear radius, radial density distribution, and single particle energies to the degree of compression. It is found that the most of increasing in the nuclear energy generated under compression is used to create the massive Δ particles. For 90Zr nucleus under compression at 2.5 times density of the normal nuclear density, the excited nucleons to Δ's are increased sharply up to 14% of the total number of constituents. This result is consistent with the values extracted from relativistic heavy-ion collisions. The single particle energy levels are calculated and their behaviors under compression are examined too. A good agreement between results with effective Hamiltonian and the phenomenological shell model for the low lying single-particle spectra is obtained. A considerable reduction in compressibility for the nucleus, and softening of the equation of state with the inclusion of the Δ's in the nuclear dynamics are suggested by the results.

  20. Dielectric response of tungsten modified Ba(Ti0.90Zr0.10O3 ceramics obtained by mixed oxide method

    Directory of Open Access Journals (Sweden)

    Francisco Moura

    2010-12-01

    Full Text Available The electrical response of Ba(Ti0.90Zr0.10O3 (BZT ceramics obtained by the mixed oxide method as a function of tungsten content was investigated. According to X-ray diffraction analysis the single phase BZT1W (1 wt.% W doped BZT and BZT2W (2 wt.% W doped BZT ceramics, crystallized in a perovskite structure, were obtained. It is also shown that tungsten substituted ceramics can be sintered at a reduced temperature when compared to the undoped BZT. Electron paramagnetic resonance (EPR analyses reveals that substitution of Ti4+ by W6+ causes distortion in the crystal structure changing lattice parameter. Substitution of W6+ on B-site of ABO3 perovskite BZT ceramics shifted the phase transition to lower temperatures up to a tungsten content of 2 wt.% leading to a relaxor-like behaviour.

  1. Temperature dependence on the electrical properties of Ba(Ti{sub 0.90}Zr{sub 0.10})O{sub 3}:2V ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Moura, F. [Laboratorio Interdisciplinar em Ceramica (LIEC), Departamento de Fisico-Quimica, Instituto de Quimica, UNESP, CEP 14800-900, Araraquara, SP (Brazil); Simoes, A.Z., E-mail: alezipo@yahoo.com [Universidade Federal de Itajuba-Unifei - Campus Itabira, Rua Sao Paulo 377, Bairro: Amazonas, CEP 35900-37, Itabira, MG (Brazil); Paskocimas, C.A.; Zaghete, M.A.; Varela, J.A.; Longo, E. [Laboratorio Interdisciplinar em Ceramica (LIEC), Departamento de Fisico-Quimica, Instituto de Quimica, UNESP, CEP 14800-900, Araraquara, SP (Brazil)

    2010-10-01

    Barium zirconium titanate ferroelectric ceramics modified with vanadium Ba(Ti{sub 0.90}Zr{sub 0.10}V{sub 0.02})O{sub 3} (BZT:2V) were prepared from powders synthesized using the mixed oxide method. The effect of temperature on the structural and electrical properties of BZT:2V ceramics was investigated. X-ray diffraction data evidenced no secondary phases. As temperature decreases, the maximum dielectric permittivity decreased. The fine-grained sample showed a 'relaxor-like' ferroelectric behavior. The dielectric permittivity reaches a maximum value ({epsilon}{sub m} {approx} 16,000 at 1 kHz) for the BZT:2V ceramics sintered at 1623 K for 4 h. Remnant polarization (P{sub r}) and coercive field were also temperature dependent.

  2. Signature of fractionally charged projectile fragments in /sup 24/Mg-emulsion interaction

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, D.; Roy, J.; Mukherjee, A.; Ghosh, A.

    1987-07-01

    From the measurement of charge of the projectile fragments produced in /sup 24/Mg-emulsion nuclei at 4.5 (GeV/c)/N, an indication of the existence of charges Z = 8/3 and 5/3 among the projectile fragments was obtained. The measurement was based on the lacunarity study of the linear structure of the ionizing track, and the percentage abundance of Z = 8/3 and 5/3 has found to be consistent with the relative abundance of anomalons.

  3. Experimental study of radiative pion capture on /sup 13/C, /sup 20/Ne, /sup 90/Zr, /sup 19/F and /sup 12/C

    Energy Technology Data Exchange (ETDEWEB)

    Martoff, C.J.

    1980-11-01

    Photon spectra for 50 < E/sub ..gamma../ < 135 MeV have been measured from the radiative capture of stopped negative pions by the nuclides /sup 13/C, /sup 19/F, /sup 20/Ne, and /sup 90/Zr. The e/sup +/e/sup -/ pair spectrometer system used has resolution 850 keV fwhm and photon detection efficiency 5 x 10/sup -6/. The total radiative capture branching ratios measured are /sup 13/C (1.66 +- 0.25)%, /sup 19/F (2.40 +- 0.48)%, /sup 20/Ne (1.60 +- 0.24)%, and /sup 90/Zr (2.1 +- 0.5)%. The partial radiative capture branching ratios to four bound states and two resonances in /sup 20/F, and two bound states and three resonances in /sup 13/B have also been measured. The branching ratio for /sup 13/C(..pi../sup -/,..gamma..)/sup 13/B g.s. is (6.1 +- 1.2) x 10/sup -4/. Comparison of this result with the beta decay rate of /sup 13/B shows that (84 +- 16)% of the pion capture amplitude is accounted for by the Gamow-Teller matrix element. Further analysis suggests that much of the remaining strength is E2. The measured branching ratios to resonant states in /sup 13/C(..pi../sup -/,..gamma..)/sup 13/B are shown to be in agreement with detailed shell model calculations. The total single-particle strength in these transitions is shown to be approximately half as large as that of the T = 3/2 part of the E1 photoresonance (the Giant Dipole Resonance) in /sup 13/C. The branching ratio for /sup 20/Ne(..pi../sup -/,..gamma..)/sup 20/F (T = 1, J/sup ..pi../ = 1/sup +/, E/sub x/ = 1.06 MeV) is 0.91 +- 0.52).10/sup -4/. Comparison with the electroexcitation of the analog giant M1 state in /sup 20/Ne (11.24 MeV) shows that the M1 transition amplitude is less than (46 +- 14)% Gamow-Teller. This result is in agreement with detailed shell model calculations of the M1 transition. The photon spectrum for radiative pion capture from flight (reaction /sup 12/C(..pi../sup +/ T = 44 MeV, ..gamma.. at 90/sup 0/)) has been measured. 13 figures, 12 tables.

  4. Splitting of ISGMR strength in the light-mass nucleus $^{24}$Mg due to ground-state deformation

    CERN Document Server

    Gupta, Y K; Matta, J T; Patel, D; Peach, T; Hoffman, J; Yoshida, K; Itoh, M; Fujiwara, M; Hara, K; Hashimoto, H; Nakanishi, K; Yosoi, M; Sakaguchi, H; Terashima, S; Kishi, S; Murakami, T; Uchida, M; Yasuda, Y; Akimune, H; Kawabata, T; Harakeh, M N

    2015-01-01

    The isoscalar giant monopole resonance (ISGMR) strength distribution in $^{24}$Mg has been determined from background-free inelastic scattering of 386-MeV $\\alpha$ particles at extreme forward angles, including 0$^{\\circ}$. The ISGMR strength distribution has been observed for the first time to have a two-peak structure in a light-mass nucleus. This splitting of ISGMR strength is explained well by microscopic theory in terms of the prolate deformation of the ground state of $^{24}$Mg.

  5. Optimization and application of ICPMS with dynamic reaction cell for precise determination of 44Ca/40Ca isotope ratios.

    Science.gov (United States)

    Boulyga, Sergei F; Klötzli, Urs; Stingeder, Gerhard; Prohaska, Thomas

    2007-10-15

    An inductively coupled plasma mass spectrometer with dynamic reaction cell (ICP-DRC-MS) was optimized for determining (44)Ca/(40)Ca isotope ratios in aqueous solutions with respect to (i) repeatability, (ii) robustness, and (iii) stability. Ammonia as reaction gas allowed both the removal of (40)Ar+ interference on (40)Ca+ and collisional damping of ion density fluctuations of an ion beam extracted from an ICP. The effect of laboratory conditions as well as ICP-DRC-MS parameters such a nebulizer gas flow rate, rf power, lens potential, dwell time, or DRC parameters on precision and mass bias was studied. Precision (calculated using the "unbiased" or "n - 1" method) of a single isotope ratio measurement of a 60 ng g(-1) calcium solution (analysis time of 6 min) is routinely achievable in the range of 0.03-0.05%, which corresponded to the standard error of the mean value (n = 6) of 0.012-0.020%. These experimentally observed RSDs were close to theoretical precision values given by counting statistics. Accuracy of measured isotope ratios was assessed by comparative measurements of the same samples by ICP-DRC-MS and thermal ionization mass spectrometry (TIMS) by using isotope dilution with a (43)Ca-(48)Ca double spike. The analysis time in both cases was 1 h per analysis (10 blocks, each 6 min). The delta(44)Ca values measured by TIMS and ICP-DRC-MS with double-spike calibration in two samples (Ca ICP standard solution and digested NIST 1486 bone meal) coincided within the obtained precision. Although the applied isotope dilution with (43)Ca-(48)Ca double-spike compensates for time-dependent deviations of mass bias and allows achieving accurate results, this approach makes it necessary to measure an additional isotope pair, reducing the overall analysis time per isotope or increasing the total analysis time. Further development of external calibration by using a bracketing method would allow a wider use of ICP-DRC-MS for routine calcium isotopic measurements, but it

  6. Cyclotron production of high purity (44m,44)Sc with deuterons from (44)CaCO3 targets.

    Science.gov (United States)

    Alliot, C; Kerdjoudj, R; Michel, N; Haddad, F; Huclier-Markai, S

    2015-06-01

    Due to its longer half-life, (44)Sc (T1/2 = 3.97 h) as a positron emitter can be an interesting alternative to (68)Ga (T1/2 = 67.71 min). It has been already proposed as a PET radionuclide for scouting bone disease and is already available as a (44)Ti/(44)Sc generator. (44)Sc has an isomeric state, (44 m)Sc (T1/2 = 58.6 h), which can be co-produced with (44)Sc and that has been proved to be considered as an in-vivo PET generator (44 m)Sc/(44)Sc. This work presents the production route of (44 m)Sc/(44)Sc generator from (44)Ca(d,2n), its extraction/purification process and the evaluation of its performances. Irradiation was performed in a low activity target station using a deuteron beam of 16 MeV, which favors the number of (44 m)Sc atoms produced simultaneously to (44)Sc. Typical irradiation conditions were 60 min at 0.2 μA producing 44 MBq of (44)Sc with a (44)Sc/(44 m)Sc activity ratio of 50 at end of irradiation. Separations of the radionuclides were performed by means of cation exchange chromatography using a DGA® resin (Triskem). Then, the developed process was applied with bigger targets, and could be used for preclinical studies. The extraction/purification process leads to a radionucleidic purity higher than 99.99% ((43)Sc, (46)Sc, (48)Sc < DL). (44 m)Sc/(44)Sc labeling towards DOTA moiety was performed in order to get an evaluation of the specific activities that could be reached with regard to all metallic impurities from the resulting source. Reaction parameters of radiolabeling were optimized, reaching yields over 95%, and leading to a specific activity of about 10-20 MBq/nmol for DOTA. A recycling process for the enriched (44)Ca target was developed and optimized. The quality of the final batch with regard to radionucleidic purity, specific activity and metal impurities allowed a right away use for further radiopharmaceutical evaluation. This radionucleidic pair of (44 m)Sc/(44)Sc offers a quite interesting PET radionuclide for being further

  7. Study of the Fusion-Fission Process in the $^{35}Cl + ^{24}Mg$ Reaction

    CERN Document Server

    Beck, C; Dayras, R; Cavallaro., Sl.

    1998-01-01

    Fusion-fission and fully energy-damped binary processes of the $^{35}$Cl+$^{24}$Mg reaction were investigated using particle-particle coincidence techniques at a $^{35}$Cl bombarding energy of E$_{lab}$ $\\approx$ 8 MeV/nucleon. Inclusive data were also taken in order to determine the partial wave distribution of the fusion process. The fragment-fragment correlation data show that the majority of events arises from a binary-decay process with a relatively large multiplicity of secondary light-charged particles emitted by the two primary excited fragments in the exit channel. No evidence is observed for ternary-breakup processes, as expected from the systematics recently established for incident energies below 15 MeV/nucleon and for a large number of reactions. The binary-process results are compared with predictions of statistical-model calculations. The calculations were performed using the Extended Hauser-Feshbach method, based on the available phase space at the scission point of the compound nucleus. This ...

  8. Decay of the excited compound system {sup 48}Cr{sup *} formed through {sup 24}Mg + {sup 24}Mg, {sup 36}Ar + {sup 12}C and {sup 20}Ne + {sup 28}Si reactions

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, K.P.; Subha, P.V.; Priyanka, B. [Kannur University, School of Pure and Applied Physics, Payyanur, Kerala (India)

    2016-05-15

    The total cross section, the intermediate mass fragment (IMF) production cross section, and the cross section for the formation of light particle (LP) for the decay of {sup 48}Cr{sup *} formed through the entrance channel {sup 24}Mg+{sup 24}Mg, have been evaluated using the barrier penetration model, taking the scattering potential as the sum of the Coulomb and nuclear proximity potential, for various E{sub CM} values. The computed results have been compared with the available experimental data of the total cross section corresponding to E{sub CM}=44.4 MeV for the entrance channel {sup 24}Mg+{sup 24}Mg, and were found to be in good agreement. The experimental values for the LP production cross section for the channel {sup 24}Mg+{sup 24}Mg were also seen to be agreeing with our calculations. Hence we have extended our studies and have thus computed the total cross section, IMF cross section and LP cross section for the decay of {sup 48}Cr{sup *} formed through the other two entrance channels {sup 36}Ar+{sup 12}C, and {sup 20}Ne+{sup 28}Si with different E{sub CM} values. It was found that the computed total cross sections for the entrance channel {sup 36}Ar+{sup 12}C with E{sub CM}=47 MeV agree well with the corresponding experimental values. Hence, we hope that our predictions on the evaluations of the IMF cross sections and the light charged particle cross sections for the decay of {sup 48}Cr{sup *}, formed through the two entrance channels {sup 36}Ar+{sup 12}C, and {sup 20}Ne+{sup 28}Si, can be used for further experimental studies. (orig.)

  9. Discovery of a 6/sup -/, T=1 resonance in /sup 24/Mg via high-resolution inelastic electron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Zarek, H.; Pich, B.O.; Drake, T.E.; Rowe, D.J.; Bertozzi, W.; Creswell, C.; Hirsch, A.; Hynes, M.V.; Kowalski, S.; Norum, B.; Rad, F.N.; Sargent, C.P.; Williamson, C.F.; Lindgren, R.A.

    1977-04-04

    The unique high-resolution and high-energy features of the electron-scattering facility at the MIT-Bates Accelerator were used to locate a dominant narrow resonance at 15.045 +- 0.035 MeV in /sup 24/Mg. A spin-parity assignment of 6/sup -/ and an isospin T=1 assignment were made. The M6 form factor was measured and compared to the prediction of a theoretical calculation which uses the open-shell random-phase approximation on a shell-model ground state for /sup 24/Mg.

  10. Splitting of ISGMR strength in the light-mass nucleus 24Mg due to ground-state deformation

    Directory of Open Access Journals (Sweden)

    Y.K. Gupta

    2015-09-01

    Full Text Available The isoscalar giant monopole resonance (ISGMR strength distribution in 24Mg has been determined from background-free inelastic scattering of 386-MeV α particles at extreme forward angles, including 0∘. The ISGMR strength distribution has been observed for the first time to have a two-peak structure in a light-mass nucleus. This splitting of ISGMR strength is explained well by microscopic theory in terms of the prolate deformation of the ground state of 24Mg.

  11. Equilibrium and pre-equilibrium calculations of cross-sections of (, ) reactions on 89Y, 90Zr and 94Mo targets used for the production of 89Zr, 90Nb and 94Tc positron-emitting radionuclides

    Indian Academy of Sciences (India)

    R Baldik; H Aytekin; E Tel

    2013-02-01

    In this study, the pre-equilibrium and equilibrium calculations of cross-sections of 89Y(, ), 90Zr$(p, xn)$ and 94Mo(, ) reactions, which were used for the production of 89Zr, 90Nb and 94Tc positron-emitting radioisotopes, have been investigated. Pre-equilibrium calculations have been performed at different proton incident energies by using the hybrid, geometry-dependent-hybrid and full exciton models. The Weisskopf–Ewing model is used for calculating the equilibrium effects at the same incident energies. The calculated results have been discussed and compared with the experimental results.

  12. Elastic and inelastic scattering of 0. 8 GeV polarized protons from /sup 24/Mg and /sup 26/Mg

    Energy Technology Data Exchange (ETDEWEB)

    Blanpied, G.S.; Ritchie, B.G.; Barlett, M.L.; Hoffmann, G.W.; McGill, J.A.; Milner, E.C.; Jones, K.W.; Nanda, S.K.; de Swiniarski, R.

    1988-05-01

    Data on 800 MeV polarized proton scattering on /sup 24/Mg and /sup 26/Mg are presented. Angular distributions and analyzing power data have been extracted from fits to 26 peaks in the spectra for /sup 24/Mg and 23 peaks in /sup 26/Mg. Although there are a variety of shapes for the angular distributions, the analyzing power data for all states are positive and similar in magnitude and seem to be consistent with a two-body operator for the excitation with a spin structure much like that for the free proton-nucleon system. Evidence for a level in /sup 26/Mg at 8.03 MeV with J>4 is presented. Comparison between the observed angular distribution, coupled channels, and distorted wave Born approximation calculations, and the angular distributions of excited states in neighboring nuclei, support the assignment of J/sup ..pi../ = 5/sup -/ or 6/sup +/. Coupled channels calculations for the 0/sup +/, 2/sup +/, 4/sup +/, and 6/sup +/ members of the ground state rotational bands of /sup 24/Mg and /sup 26/Mg are compared to the data. Deformation parameters from distorted wave Born approximation calculations are determined for most of the angular distributions.

  13. Surface absorption in the {sup 32}S+{sup 24}Mg interactions at energies near the Coulomb barrier

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco, J.C.; Sanchez, F.; Diaz, J.; Ferrero, J.L. [Valencia Univ. (Spain); Bilwes, B. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Ruiz, J.A. [Universidad Publica de Navarra, Pamplona (Spain); Kadi-Hanifi, D. [Universite de Blida (Algeria)

    1995-12-31

    Elastic scattering {sup 32} S on {sup 24} Mg has been measured at 65.0, 75.0, 86.3, 95.0 and 110.0 MeV-lab energies, and the data were systematically analysed with semi-phenomenological potentials. Using microscopic potentials we found similar results at the lowest incident energies, for which we have compared both the microscopic and semi-phenomenological potentials. It appears that the absorption takes place in a narrow range at the nuclear surface and is mainly due to the low lying collective surface states. (author). 41 refs., 11 figs., 4 tabs.

  14. Formation of 24Mg* in the spallation of 28Si nuclei by 1-GeV protons

    Science.gov (United States)

    Vasenko, A. A.; Galanina, N. D.; Gusev, K. E.; Demidov, V. S.; Demidova, E. V.; Kirpichnikov, I. V.; Sokolov, A. Yu.; Starostin, A. S.; Khaldeeva, N. A.

    2006-11-01

    The 28Si(p, p' gamma)24Mg reaction has been studied at the ITEP accelerator by the hadron-gamma coincidence method for a proton energy of 1 GeV. Two reaction products are detected: a 1368.6-keV gamma-ray photon accompanying the transition of the 24Mg* nucleus from the first excited state to the ground state and a proton p' whose momentum is measured in a magnetic spectrometer. The measured distribution in the energy lost by the proton in interaction is attributed to five processes: the direct knockout of a nuclear alpha cluster, the knockout of four nucleons with a total charge number of 2, the formation of the DeltaSi isobaric nucleus, the formation of the Delta isobar in the interaction of the incident proton with a nuclear nucleon, and the production of a pi meson, which is at rest in the nuclear reference frame. The last process likely corresponds to the reaction of the formation of a deeply bound pion state in the 28P nucleus. Such states were previously observed only on heavy nuclei. The cross sections for the listed processes have been estimated.

  15. Formation of 24Mg* in the Splitting of 28Si Nuclei by 1-GeV Protons

    CERN Document Server

    Vasenko, A A; Gusev, K E; Demidov, V S; Demidova, E V; Kirpichnikov, I V; Sokolov, A Yu; Starostin, A S; Khaldeeva, N A

    2006-01-01

    The 28Si(p, p' gamma)24Mg reaction has been studied at the ITEP accelerator by the hadron-gamma coincidence method for a proton energy of 1 GeV. Two reaction products are detected: a 1368.6-keV gamma-ray photon accompanying the transition of the 24Mg* nucleus from the first excited state to the ground state and a proton p' whose momentum is measured in a magnetic spectrometer. The measured distribution in the energy lost by the proton in interaction is attributed to five processes: the direct knockout of a nuclear alpha cluster, the knockout of four nucleons with a total charge number of 2, the formation of the DeltaSi isobaric nucleus, the formation of the Delta isobar in the interaction of the incident proton with a nuclear nucleon, and the production of a pi meson, which is at rest in the nuclear reference frame. The last process likely corresponds to the reaction of the formation of a deeply bound pion state in the 28P nucleus. Such states were previously observed only on heavy nuclei. The cross sections ...

  16. (/sup 6/Li,d) reactions on /sup 24/Mg and /sup 26/Mg at 73 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Tanabe, T.; Haga, K.; Yasue, M.; Sato, K. (Tokyo Univ., Tanashi (Japan). Inst. for Nuclear Study); Ogino, K.; Kadota, Y.; Tochi, M.; Makino, K. (Kyoto Univ. (Japan). Faculty of Engineering); Kitahara, T. (Yamanashi Medical Coll. (Japan)); Shiba, T. (Kyoto Univ. (Japan). Lab. of Nuclear Reaction)

    1983-05-09

    The sup(24,26)Mg(/sup 6/Li, d)sup(28,30)Si reactions have been studied at 73 MeV bombarding energy. The angular distributions were analyzed with exact finite-range distorted wave Born approximation calculations assuming a direct ..cap alpha..-cluster transfer. Extracted spectroscopic strengths leading to low-lying levels of /sup 28/Si and relative spectroscopic strengths between transitions to /sup 28/Si and /sup 30/Si ground states are consistent with those previously obtained by several ..cap alpha..-transfer reactions. Many strongly populated levels have been observed at Esub(x)> or approx.10 MeV for /sup 28/Si. A marked similarity was found between the deuteron spectrum and the /sup 24/Mg(..cap alpha.., ..cap alpha..)/sup 24/Mg excitation function in this excitation energy region. A brief comparison of the present ..cap alpha..-transfer results with previous two-nucleon transfer data leading to sup(28,30)Si is also presented.

  17. Nuclear molecules and their deexcitation channels, case of Cr{sup 48} generated by the Mg{sup 24} + Mg{sup 24} resonant reaction; Molecules nucleaires et leurs modes de desexcitation: le cas du {sup 48}Cr et de la reaction resonante {sup 24}Mg + {sup 24}Mg

    Energy Technology Data Exchange (ETDEWEB)

    Salsac, M.D

    2006-12-15

    This work is dedicated to the study of the resonance (E = 45,7 MeV, J{sup {pi}} = 36{sup +}, {gamma} = 170 keV) of the Mg{sup 24} + Mg{sup 24} composite nucleus. The PRISMA fragment spectrometer combined with the CLARA gamma detector have been used to study the deexcitation through inelastic channels of the composite system. It is showed that the resonant flux is mainly observed in the inelastic channels involving the contributions 0{sup +}, 2{sup +} and 4{sup +} of the band based on the fundamental state of Mg{sup 24}. This is in good agreement with the theoretical predictions of the molecular model of Uegaki and Abe. Only 30% of the resonant flux has been observed in the inelastic channels and in the transfer channels. The missing flux has been investigated in the fusion/evaporation deexcitation channels with the GASP gamma multi-detector. A weak resonant effect has been highlighted in some residual nuclei such as Ti{sup 45}, Ca{sup 42} and K{sup 39}. A link between the prolate di-nucleus Ca{sup 48} generated in Mg{sup 24} + Mg{sup 24} reaction and a Cr{sup 48} nucleus that has just undergone a Jacobi transition from oblate to prolate, has been discovered. To explain a part of the missing flux it is suggested that the dipolar giant resonance might feed very deformed nuclei through particle emission.

  18. Three-Dimensional Angular Momentum Projected Relativistic Point-Coupling Approach for Low-Lying Excited States in 24Mg

    Institute of Scientific and Technical Information of China (English)

    Yao Jiang-Ming; Meng Jie; D. Pena Arteaga; P. Ring

    2008-01-01

    A full three-dimensional angular momentum projection on top of a triaxial relativistic mean-field calculation is implemented for the first time. The underlying Lagrangian is a point coupling model and pairing correlations are taken into account by a monopole force. This method is applied for the low-lying excited states in 24Mg. Good agreement with the experimental data is found for the ground state properties. A minimum in the potential energy surface for the 2+ state, with β≈ 0.55, γ≈ 10°, is used as the basis to investigate the rotational energyspectrum as well as the corresponding B(E2) transition probabilities as compared to the available data.

  19. Configuration mixing of mean-field wave-functions projected on angular momentum and particle number; application to 24Mg

    CERN Document Server

    Valor, A; Bonche, P

    2000-01-01

    We present in this paper the general framework of a method which permits to restore the rotational and particle number symmetries of wave functions obtained in Skyrme HF+BCS calculations. This restoration is nothing but a projection of mean-field intrinsic wave functions onto good particle number and good angular momentum. The method allows also to mix projected wave functions. Such a configuration mixing is discussed for sets of HF+BCS intrinsic states generated in constrained calculations with suitable collective variables. This procedure gives collective states which are eigenstates of the particle number and the angular momentum operators and between which transition probabilities are calculated. An application to 24Mg is presented, with mean-field wave functions generated by axial quadrupole constraints. Theoretical spectra and transition probabilities are compared to the experiment.

  20. The 12C* Hoyle state in the inelastic 12C + 12C reaction and in 24Mg* decay

    Science.gov (United States)

    Morelli, L.; Bruno, M.; D'Agostino, M.; Baiocco, G.; Gulminelli, F.; Abbondanno, U.; Barlini, S.; Bini, M.; Casini, G.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gramegna, F.; Mabiala, J.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Valdré, S.

    2016-08-01

    The reaction 12C + 12C at 95 MeV has been studied at the Legnaro Laboratories of INFN with the GARFIELD + RCo apparatus. Data have been analyzed in order to investigate the decay of the Hoyle state of 12C*. Two different data selections have been made. The first one corresponds to peripheral binary collisions where the quasi-projectile is excited to the Hoyle state and the target has been left in the ground state. The second selection allows for studying central events with the formation of a 24Mg* and the Hoyle state is obtained as a step of the decay chain. The characteristics of the Hoyle state decay are very similar in the two samples and point to a mainly sequential decay through the population of an intermediate 8Begs, with a small contribution (˜1.1%) from simultaneous three α-particle processes.

  1. Separation of reaction mechanisms at low energy. Study of the reactions: {sup 27}Al(d,p) {sup 28}Al, {sup 24}Mg(d,p) {sup 25}Mg, and {sup 24}Mg(d, {alpha}) {sup 22}Na; Sur la separation des mecanismes de reaction a basse energie. Etude des reactions: {sup 27}Al(d,p) {sup 28}Al, {sup 24}Mg(d,p) {sup 25}Mg, et {sup 24}Mg(d, {alpha}) {sup 22}Na

    Energy Technology Data Exchange (ETDEWEB)

    Mermaz, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-06-01

    The two sets of angular distributions of (d,p) reactions on Al and Mg, measured between 2 and 6 MeV, have given the possibility to test, in analysing the statistical fluctuations of cross-section, the validity of the separation of their mean values in two parts, one 'direct', another given by the statistical mechanism. With the same method of analysis we have studied excitation functions for several alpha groups of the reaction {sup 24}Mg(d, {alpha}) {sup 22}Na and given an evidence for an intermediate structure for the alpha channel leading to the 3. excited state of {sup 22}Na. The angular distribution of the wide resonance at 15.9 MeV in {sup 26}Al has been obtained. (author) [French] Les deux ensembles de distributions angulaires des reactions (d,p) sur Al et Mg, mesures entre 2 et 6 MeV, nous ont permis, en analysant les fluctuations statistiques de sections efficaces, de verifier la possibilite de la separation de leurs valeurs moyennes en deux composantes: l'une 'directe', l'autre due au mecanisme statistique. Avec la meme methode d'analyse nous avons etudie les fonctions d'excitation des premiers groupes alpha de la reaction {sup 24}Mg(d,{alpha}) {sup 22}Na et mis en evidence une structure intermediaire pour la voie de reaction aboutissant au 3eme niveau de {sup 22}Na. Nous avons obtenu la distribution angulaire de la resonance large situee a une energie d'excitation de 15,9 MeV dans {sup 26}Al. (auteur)

  2. Production of scandium-43 and -47 from a powdery calcium oxide target via the (nat/44)Ca(α,x)-channel.

    Science.gov (United States)

    Minegishi, Katsuyuki; Nagatsu, Kotaro; Fukada, Masami; Suzuki, Hisashi; Ohya, Tomoyuki; Zhang, Ming-Rong

    2016-10-01

    We produced (43)Sc and (47)Sc via the (nat/44)Ca(α,x)-channel using a vertical beam coupled with a ceramic target box. After activation, the powdery CaO target material was dissolved in HCl in the target box in situ and remotely recovered as a radio-Sc solution. The respective yields of (43)Sc and (47)Sc following isolation via a precipitation method with a typical 0.22µm sterile filter were 54.8MBq/µAh (1.48mCi/µAh) and 780kBq/µAh (21.1µCi/µAh) at the end of separation (approximately 1.5h from the EOB). In addition, we discuss the recycling of target Ca.

  3. In-situ Electric Field-Induced Modulation of Photoluminescence in Pr-doped Ba0.85Ca0.15Ti0.90Zr0.10O3 Lead-Free Ceramics

    Science.gov (United States)

    Sun, Hai Ling; Wu, Xiao; Chung, Tat Hang; Kwok, K. W.

    2016-01-01

    Luminescent materials with dynamic photoluminescence activity have aroused special interest because of their potential widespread applications. One proposed approach of directly and reversibly modulating the photoluminescence emissions is by means of introducing an external electric field in an in-situ and real-time way, which has only been focused on thin films. In this work, we demonstrate that real-time electric field-induced photoluminescence modulation can be realized in a bulk Ba0.85Ca0.15Ti0.90Zr0.10O3 ferroelectric ceramic doped with 0.2 mol% Pr3+, owing to its remarkable polarization reversal and phase evolution near the morphotropic phase boundary. Along with in-situ X-ray diffraction analysis, our results reveal that an applied electric field induces not only typical polarization switching and minor crystal deformation, but also tetragonal-to-rhombohedral phase transformation of the ceramic. The electric field-induced phase transformation is irreversible and engenders dominant effect on photoluminescence emissions as a result of an increase in structural symmetry. After it is completed in a few cycles of electric field, the photoluminescence emissions become governed mainly by the polarization switching, and thus vary reversibly with the modulating electric field. Our results open a promising avenue towards the realization of bulk ceramic-based tunable photoluminescence activity with high repeatability, flexible controllability, and environmental-friendly chemical process. PMID:27339815

  4. Effect of oxidizing and reducing atmospheres on Ba(Ti0.90Zr0.10O3:2V ceramics as characterized by piezoresponse force microscopy

    Directory of Open Access Journals (Sweden)

    Francisco Moura

    2011-09-01

    Full Text Available The effect of annealing atmospheres (At amb, N2 and O2 on the electrical properties of Ba(Ti0.90Zr0.10O3:2V (BZT10:2V ceramics obtained by the mixed oxide method was investigated. X-ray photoelectron spectroscopy (XPS analysis indicates that oxygen vacancies present near Zr and Ti ions reduce ferroelectric properties, especially in samples treated in an ambient atmosphere (At amb. BZT10:2V ceramics sintered in a nitrogen atmosphere showed better dielectric behaviour at room temperature with a dielectric permittivity measured at a frequency of 10 kHz equal to 16800 with dielectric loss of 0.023. Piezoelectric force microscopy (PFM images reveal improvement in the piezoelectric coefficient by sintering the sample under nitrogen atmosphere. Thus, BZT10:2V ceramics sintered under a nitrogen atmosphere can be useful for practical applications which include nonvolatile digital memories, spintronics and data-storage media.

  5. Detailed microscopic calculation of stellar electron and positron capture rates on $^{24}$Mg for O+Ne+Mg core simulations

    CERN Document Server

    Nabi, Jameel-Un

    2014-01-01

    Few white dwarfs, located in binary systems, may acquire sufficiently high mass accretion rates resulting in the burning of carbon and oxygen under nondegenerate conditions forming a O+Ne+Mg core. These O+Ne+Mg cores are gravitationally less bound than more massive progenitor stars and can release more energy due to the nuclear burning. They are also amongst the probable candidates for low entropy r-process sites. Recent observations of subluminous Type II-P supernovae (e.g., 2005cs, 2003gd, 1999br, 1997D) were able to rekindle the interest in 8 -- 10 M$_{\\odot}$ which develop O+Ne+Mg cores. Microscopic calculations of capture rates on $^{24}$Mg, which may contribute significantly to the collapse of O+Ne+Mg cores, using shell model and proton-neutron quasiparticle random phase approximation (pn-QRPA) theory, were performed earlier and comparisons made. Simulators, however, may require these capture rates on a fine scale. For the first time a detailed microscopic calculation of the electron and positron captur...

  6. Calculation of vibrational branching ratios and hyperfine structure of 24Mg19F and its suitability for laser cooling and magneto-optical trapping

    Science.gov (United States)

    Xu, Liang; Yin, Yanning; Wei, Bin; Xia, Yong; Yin, Jianping

    2016-01-01

    More recently, laser cooling of the diatomic radical magnesium monofluoride (24Mg19F ) is being experimentally preformed [Appl. Phys. Express 8, 092701 (2015), 10.7567/APEX.8.092701 and Opt. Express 22, 28645 (2014), 10.1364/OE.22.028645] and was also studied theoretically [Phys. Rev. A 91, 042511 (2015), 10.1103/PhysRevA.91.042511]. However, some important problems still remain unsolved, so, in our paper, we perform further theoretical study for the feasibility of laser cooling and trapping the 24Mg19F molecule. At first, the highly diagonal Franck-Condon factors of the main transitions are verified by the closed-form approximation, Morse approximation, and Rydberg-Klein-Rees inversion methods, respectively. Afterwards, we investigate the lower X 2Σ1/2 + hyperfine manifolds using a quantum effective Hamiltonian approach and obtain the zero-field hyperfine spectrum with an accuracy of less than 30 kHz ˜5 μ K compared with the experimental results, and then find out that one cooling beam and one or two repumping beams with their first-order sidebands are enough to implement an efficient laser slowing and cooling of 24Mg19F . Meanwhile, we also calculate the accurate hyperfine structure magnetic g factors of the rotational state (X 2Σ1/2 +,N =1 ) and briefly discuss the influence of the external fields on the hyperfine structure of 24Mg19F as well as its possibility of preparing three-dimensional magneto-optical trapping. Finally we give an explanation for the difference between the Stark and Zeeman effects from the perspective of parity and time reversal symmetry. Our study shows that, besides appropriate excitation wavelengths, the short lifetime for the first excited state A 2Π1 /2 , and lighter mass, the 24Mg19F radical could be a good candidate molecule amenable to laser cooling and magneto-optical trapping.

  7. Semi empirical formula for electronic stopping power determination of 24Mg, 27Al and 28Si ions crossing Formvar foil in the ion energy domain of LSS theory

    Science.gov (United States)

    Guesmia, A.; Ammi, H.; Mammeri, S.; Dib, A.; Pineda-Vargas, C. A.; Msimanga, M.; Hedibel, M.

    2014-03-01

    We have determined continuous stopping power of heavy ions in thin Formvar foil for 28Si, 27Al and 24Mg ions over an energy range of (0.1-0.5) MeV/nucleon. Heavy Ions Elastic Recoil Detection Analysis (HI-ERDA) technique coupled with time of flight (ToF) spectrometer has been used to measure energy loss of charged particles in this thin absorber. Lindhard, Scharff and Schiott (LSS) theory compared with the corresponding determined stopping values in Formvar, shows significantly large deviations. However, a novel semi empirical expression has been proposed here and tested for better stopping power calculations at low velocity in the ion energy domain of LSS theory for 28Si, 27Al and 24Mg ions crossing thin Formvar foil. The results were compared to the obtained experimental stopping power data, predictions of LSS theory and also to those generated by SRIM-2010 computer code. The obtained results exhibit good agreement with experimental data.

  8. Dirac Coupled-channel Analyses of Polarized Proton Scatterings to the 2$^+$ Gamma Vibrational Band in $^{24}$Mg and $^{26}$Mg

    CERN Document Server

    Shim, Sugie

    2016-01-01

    Dirac coupled channel calculations are performed phenomenologically for the high-lying excited states that belong to the 2$^+$ gamma vibrational band at the 800-MeV polarized proton inelastic scatterings from the s-d shell nuclei, $^{24}$Mg and $^{26}$Mg. Optical potential model is used and scalar and time-like vector potentials are considered as direct potentials. First-order vibrational collective models are used to obtain the transition optical potentials in order to accommodate the high-lying excited vibrational collective states. The complicated Dirac coupled channel equations are solved phenomenologically to reproduce the differential cross section and analyzing power data by varying the optical potential and deformation parameters. It is found that the relativistic Dirac coupled channel calculation could describe the high-lying excited states of the 2$^+$ gamma vibrational band at the 800-MeV polarized proton inelastic scatterings from s-d shell nuclei $^{24}$Mg and $^{26}$Mg reasonably well, showing b...

  9. Isovector stretched-state excitations in the sup 20 Ne, sup 24 Mg, sup 28 Si, and sup 32 S( p , n ) reactions at 136 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Tamimi, N.; Anderson, B.D.; Baldwin, A.R.; Chittrakarn, T.; Elaasar, M.; Madey, R.; Manley, D.M.; Mostajabodda' vati, M.; Watson, J.W.; Zhang, W. (Department of Physics, Kent State University, Kent, Ohio 44242 (United States)); Carr, J.A. (Supercomputer Computations Research Institute, The Florida State University, Tallahassee, Florida 32306 (United States)); Foster, C.C. (Indiana University Cyclotron Facility, Bloomington, Indiana 47408 (United States))

    1992-03-01

    Isovector stretched-state excitations were studied in the ({ital p},{ital n}) reaction at 136 MeV on the self-conjugate {ital s}-{ital d} shell nuclei {sup 20}Ne, {sup 24}Mg, {sup 28}Si, and {sup 32}S. The measurements were performed in three separate experiments using the beam-swinger neutron time-of-flight facility at the Indiana University Cyclotron Facility. Neutrons were detected in large-volume plastic scintillation detectors located in three detector stations at 0{degree}, 24{degree}, and 45{degree} with respect to the undeflected beam line; the flight paths varied from 75 to 134 m. Overall time resolutions of about 825 ps provided energy resolutions of about 320 keV in the first two stations and about 425 keV in the third station. Both ({ital d}{sub 5/2},{ital d}{sub 5/2}{sup {minus}1})5{sup +} 0{h bar}{omega} and ({ital f}{sub 7/2},{ital d}{sub 5/2}{sup {minus}1})6{sup {minus}} 1{h bar}{omega} stretched-state excitations are observed in the ({ital p},{ital n}) reaction on {sup 20}Ne, {sup 24}Mg, and {sup 28}Si.

  10. Actinide production from the interactions of sup 40 Ca and sup 44 Ca with sup 248 Cm and a comparison with the sup 48 Ca+ sup 248 Cm system

    Energy Technology Data Exchange (ETDEWEB)

    Tuerler, A.; von Gunten, H.R. (Laboratorium fuer Radiochemie, Universitaet Bern, 3000 Bern 9 (Switzerland)); Leyba, J.D.; Hoffman, D.C.; Lee, D.M.; Gregorich, K.E.; Bennett, D.A.; Chasteler, R.M.; Gannett, C.M.; Hall, H.L.; Henderson, R.A.; Nurmia, M.J. (Nuclear Science Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States))

    1992-10-01

    Excitation functions have been measured for production of isotopes of Th through Fm in bombardments of {sup 248}Cm with 231- to 323-MeV {sup 44}Ca ions and for the production of isotopes of Th through Cm in bombardments of {sup 248}Cm with 230- to 291-MeV {sup 40}Ca ions, respectively, using radiochemical methods. Upper production cross section limits were established for nuclides that were not positively detected. The experimental data were compared with the results of previous reaction studies in the systems {sup 40}Ca+{sup 248}Cm and {sup 48}Ca+{sup 248}Cm. The half-widths of the Gaussian isotopic distributions were about 2.5 mass numbers for above-target elements and 5 to 5.5 mass numbers for below-target elements in all three systems. The majority of the cross section for the production of above-target nuclides was assigned to predominantly quasielastic reactions, whereas below-target nuclides were formed in deeply inelastic and asymmetric quasifission reactions. The maxima of the isotopic distributions were shown by others to closely follow the minimum of the potential energy surface in experiments with {sup 48}Ca, whereas in reactions with {sup 40}Ca and {sup 44}Ca we found that a transfer of 4 to 5 protons in either direction was required to reach the minimum in potential energy.

  11. $^{8}$Be, $^{12}$C, $^{16}$O, $^{20}$Ne, $^{24}$Mg, and $^{32}$S nuclei and alpha clustering within a generalized liquid drop model

    CERN Document Server

    Royer, G; Eudes, P

    2015-01-01

    The potential energy governing the shape and the entrance and decay channels of the 12 C, 16 O, 20 Ne, 24 Mg, and 32 S 4n-nuclei has been determined within a generalized liquid drop model. Different three-dimensional and planar shapes have been investigated: linear chain, triangle, square, tetrahedron, pentagon, trigonal bipyramid, square pyramid, hexagon, octahedron, octogon and cube. The rms radii of the linear chains are higher than the experimental rms radii of the ground states. The binding energies of the planar shapes at the contact point are lower than the ones of the three-dimensional configurations. The a particle plus A-4 daughter configuration leads always to the lowest potential barrier relatively to the sphere configuration.

  12. Clustering effects in fusion evaporation reactions with light even-even N = Z nuclei. The {sup 24}Mg and {sup 28}Si cases

    Energy Technology Data Exchange (ETDEWEB)

    Morelli, L., E-mail: luca.morelli@bo.infn.it; D’Agostino, M.; Bruno, M. [Dipartimento di Fisica e Astronomia dell’Università and INFN, Bologna (Italy); Baiocco, G. [Dipartimento di Fisica dell’Università and INFN, Pavia (Italy); Gulminelli, F. [CNRS, LPC, Caen, France and ENSICAEN, Caen (France); Cinausero, M.; Gramegna, F.; Marchi, T. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy); Degerlier, M. [University of Nevsehir, Physics Department, Nevsehir (Turkey); Fabris, D. [INFN, Sezione di Padova, Padova (Italy); Barlini, S.; Bini, M.; Casini, G.; Gelli, N.; Olmi, A.; Pasquali, G.; Piantelli, S. [Dipartimento di Fisica e Astronomia dell’Università and INFN, Firenze (Italy)

    2015-10-15

    In the recent years, cluster structures have been evidenced in many ground and excited states of light nuclei [1, 2]. Within the currently ongoing experimental campaign by the NUCL-EX collaboration we have measured the {sup 12}C+{sup 12}C and {sup 14}N+{sup 10}B reactions at 95 MeV and 80 MeV respectively, and compared experimental data corresponding to complete fusion of target and projectile into an excited {sup 24}Mg nucleus to the results of a pure statistical model[3, 4]. We found clear deviations from the statstical model in the decay pattern: emission channels involving multiple α particles are more probable than expected from a purely statistical behavior. To continue the investigation on light systems, we have recentely measured the {sup 16}O+{sup 12}C reaction at three different beam energies, namely E{sub beam} = 90, 110 and 130 MeV.

  13. Three-dimensional angular momentum projected relativistic point-coupling approach for the low-lying excited states in $^{24}$Mg

    CERN Document Server

    Yao, J M; Arteaga, D Pena; Ring, P; 10.1088/0256-307X/25/10/024

    2008-01-01

    A full three-dimensional angular momentum projection on top of a triaxial relativistic mean-Geld calculation is implemented for the first time. The underlying Lagrangian is a point coupling model and pairing correlations are taken into account by a monopole force. This method is applied for the low-lying excited states in 24Mg. Good agreement with the experimental data is found for the ground state properties. A minimum in the potential energy surface for the 2+ state, with beta = 0.55, gamma = 10 deg, is used as the basis to investigate the rotational energy spectrum as well as the corresponding B(E2) transition probabilities as compared to the available data.

  14. Study of two- and multi-particle correlations in 12C+24Mg and 12C+208Pb reactions at E=35 AMeV

    Directory of Open Access Journals (Sweden)

    Quattrocchi L.

    2016-01-01

    Full Text Available Two and multi particle correlations from the decay of sources produced in 12C+24Mg and 12C+208Pb collisions at E=35 AMeV have been studied by using the forward part (1° < θlab < 30° of the CHIMERA multi-detector. Correlations and invariant mass spectroscopy are used to explore simultaneous and sequential decays of resonances in light isotopes with Z∼3-6, produced in peripheral collisions via the break-up of excited quasi-projectiles. Among them we mention 5Li, 6Li, 6Be, 8Be and the astrophysically important state in 12C decaying into three alpha particles. Results and future perspectives at the INFN-LNS will be presented.

  15. Gamow-Teller strength in the ( p , n ) reaction at 136 MeV on sup 20 Ne, sup 24 Mg, and sup 28 Si

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, B.D.; Tamimi, N.; Baldwin, A.R.; Elaasar, M.; Madey, R.; Manley, D.M.; Mostajabodda' vati, M.; Watson, J.W.; Zhang, W.M. (Department of Physics, Kent State University, Kent, Ohio 44242 (USA)); Foster, C.C. (Indiana University Cyclotron Facility, Bloomington, Indiana 47408 (USA))

    1991-01-01

    Gamow-Teller (GT) strength distributions were studied in the ({ital p},{ital n}) reaction at 136 MeV on the self-conjugate {ital s}-{ital d} shell nuclei {sup 20}Ne, {sup 24}Mg, and {sup 28}Si. The measurements were performed in two separate experiments with the beam-swinger neutron time-of-flight facility at the Indiana University Cyclotron Facility. The flight paths were 91 and 131 m, respectively, for the two experiments. The neutrons were detected in large-volume plastic-scintillation detectors. The overall time resolutions were about 825 ps; this provided energy resolutions from 300 to 400 keV. GT strength was identified as {Delta}{ital l}=0 contributions in transitions to discrete final states and also in the background and continuum. The 0{degree}, {Delta}l=0 cross sections were converted to {ital B}(GT) units using a universal'' conversion formula calibrated to ({ital p},{ital n}) reactions on other even-even {ital s}-{ital d} shell nuclei. The resulting {ital B}(GT) distributions were compared with full {ital s}-{ital d} shell-model predictions. The distribution for {sup 24}Mg is described well, but the distributions for {sup 20}Ne and {sup 28}Si are described poorly. The total {ital B}(GT) strength observed in discrete states (up to 12 MeV of excitation) for each reaction is 65{plus minus}10 % of that predicted. If one considers {ital B}(GT) strength observed in the continuum above a calculated quasi-free-scattering background, the strength increases to 70--100 % of that predicted. If one considers {ital B}(GT) strength in an analysis of the full continuum (up to {similar to}20 MeV), the entire amount predicted may be observed. These results are consistent with that observed in other light nuclei.

  16. Clustering effects in fusion evaporation reactions with light even-even N=Z nuclei. The 24Mg and 28Si cases

    Science.gov (United States)

    Morelli, L.; Bruno, M.; D'Agostino, M.; Baiocco, G.; Gulminelli, F.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gramegna, F.; Marchi, T.; Barlini, S.; Bini, M.; Casini, G.; Gelli, N.; Pasquali, G.; Piantelli, S.; Valdrè, S.

    2016-06-01

    In the recent years, cluster structures have been evidenced in many ground and excited states of light nuclei [1, 2]. The decay of highly excited states of 24Mg is studied in fusion evaporation events completely detected in charge in the reactions 12C+12C and 14N+10B at 95 and 80 MeV incident energy, respectively, and compared to the results of a pure statistical model [3, 4]. Inclusive variables are in general well reproduced by the model. We found clear deviations from the statistical model if we select emission channels involving multiple α particles which are more probable than expected from a purely statistical behavior. Data from 12C+12C reaction have been analyzed in order to study the decay of the Hoyle state of 12C* with two different selections: peripheral binary collisions and 6α decay channel in central events. To continue the investigation on light systems, we have recently measured the 16O+12C reaction at three different beam energies, namely Ebeam = 90, 110 and 130 MeV. Preliminary results are presented.

  17. Co-hydrothermal synthesis of LiMn23/24Mg1/24PO4·LiAlO2/C nano-hybrid cathode material with enhanced electrochemical performance for lithium-ion batteries

    Science.gov (United States)

    Zhang, Jun; Luo, Shaohua; Chang, Longjiao; Hao, Aimin; Wang, Zhiyuan; Liu, Yanguo; Xu, Qian; Wang, Qing; Zhang, Yahui

    2017-02-01

    LiMn23/24Mg1/24PO4·LiAlO2/C is synthesized by a co-hydrothermal method in water/PEG system using Li2CO3, AAO and Mn1-xMgxPO4 as raw material. The electronic structure and micromorphology of multi-component compound LiMn1-xMgxPO4/C (x = 0, 1/24, 1/12, 1/6) and nano-hybrid LiMn23/24Mg1/24PO4·LiAlO2/C cathode materials are studied by first-principles calculation and experimental research including XRD, SEM, TEM. The calculated band gap of LiMn23/24Mg1/24PO4/C is 2.296 eV, which is lower than other percentages Mg2+ doping samples. Electrochemical tests exhibit LiMn23/24Mg1/24PO4/C has better cycling performance and rate capability than other contents Mg2+ doping samples with the discharge capacity of 143.5 mAh/g, 141.5 mAh/g, 139.2 mAh/g and 136.3 mAh/g at 0.05C, 0.1C, 0.5C and 1C in order. After compositing and preparation of LiMn23/24Mg1/24PO4·LiAlO2/C composite material by co-hydrothermal route, the initial discharge capacity reaches up to 151.8 mAh/g, which suggests that co-modified with Mg2+ doping and LiAlO2 compositing material can improve the electronic conductivity of LiMnPO4/C by facilitating the lithium ion diffusion rate in the interior of the materials.

  18. Study of the angular correlations of light charged particles for the reaction {sup 35}CI (260 MeV) + {sup 24}Mg; Etude des correlations angulaires de particules legeres chargees dans la reaction {sup 35}CI (260 MeV) + {sup 24}Mg

    Energy Technology Data Exchange (ETDEWEB)

    Mahboub, D.

    1996-10-30

    This work is focussed on the investigation of deformed nuclei. The asymmetric fusion-fission of light heavy-ions (A {<=}60) with a high excitation energy (T {approx} 4 MeV) had lead to a large deformation of the compound nucleus at the scission point. The angular correlations between light particles (LP) and their emitting fragments has been used to probe the deformation of nucleus. Exclusive measurements were performed for the {sup 35}Cl (260 MeV) + {sup 24}Mg system leading to the {sup 59}Cu compound nucleus (CN). The comparison between the energy spectra of LP`s and a statistical calculation carried out by a Monte-Carlo code CASCADE has suggested a deformation of 1.3 (for an oblate shape) of the CN within the frame work of fusion-evaporation process. The source velocity spectrum of {alpha} particles and angular correlations of LP`s have showed that pre-scission and pre-equilibrium emissions are negligible in the present reaction. Finally the confrontation of the data with the statistical code GEMINI has pointed out the sequential emission character of the LP`s from the fission fragments. (author). 175 refs.

  19. Investigation of exotic modes of spinning nuclei near 90Zr

    Indian Academy of Sciences (India)

    R Palit; S Saha

    2014-04-01

    Recently, a digital data acquisition system with 96 channels has been set up for the Indian National Gamma Array (INGA) consisting of 24 Compton-suppressed clover detectors. The digital system provides higher throughput, better energy resolution and better stability for the multidetector Compton-suppressed clover array compared to the previous conventional system with analog shaping. A number of nuclear spectroscopic experiments have been carried out using the array. Selected results from this array will be presented which highlight different excitations of nuclei near-shell gaps.

  20. Ab initio study on vibrational dipole moments of XH{sup +} molecular ions: X = {sup 24}Mg, {sup 40}Ca, {sup 64}Zn, {sup 88}Sr, {sup 114}Cd, {sup 138}Ba, {sup 174}Yb and {sup 202}Hg

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Minori; Hada, Masahiko [Department of Chemistry, Tokyo Metropolitan University, 1-1, Minami-Osawa, Hachioji, Tokyo 192-0397 (Japan); Kajita, Masatoshi [National Institute of Information and Communications Technology, Nukui-Kitamachi, Koganei, Tokyo 184-8795 (Japan); Moriwaki, Yoshiki, E-mail: minoria@tmu.ac.j [Department of Physics, University of Toyama, Gofuku, Toyama, 930-8555 (Japan)

    2010-12-28

    The vibrational matrix elements of electric dipole moments were theoretically estimated for the electronic ground state of XH{sup +} molecular ions (X = {sup 24}Mg, {sup 40}Ca, {sup 64}Zn, {sup 88}Sr, {sup 114}Cd, {sup 138}Ba, {sup 174}Yb and {sup 202}Hg) using the complete active space second-order perturbation theory method. Because of the large rotational constant and zero X-nuclear spin, these molecules are advantageous to be localized to a single (v, J, F) state, where v, J, F are quantum numbers of the vibrational, rotational and hyperfine states, respectively. The information of the dipole moments is very useful to discuss the period to localize the molecular ion to the (v, J, F) = (0, 0, 1/2) state and also the period to remain in this state, which is limited by the interaction with the black body radiation. The agreement of experimental and our theoretical spectroscopic constants ensures the accuracy of our results. Vibrational permanent and transition dipole moments were obtained with special care of accuracy in numerical integration. Spontaneous emission rates were calculated from the vibrational dipole moments and transition energies.

  1. Interfacial magnetic anisotropy of Co90Zr10 on Pt layer.

    Science.gov (United States)

    Kil, Joon Pyo; Bae, Gi Yeol; Suh, Dong Ik; Choi, Won Joon; Noh, Jae Sung; Park, Wanjun

    2014-11-01

    Spin Transfer Torque (STT) is of great interest in data writing scheme for the Magneto-resistive Random Access Memory (MRAM) using Magnetic Tunnel Junction (MTJ). Scalability for high density memory requires ferromagnetic electrodes having the perpendicular magnetic easy axis. We investigated CoZr as the ferromagnetic electrode. It is observed that interfacial magnetic anisotropy is preferred perpendicular to the plane with thickness dependence on the interfaces with Pt layer. The anisotropy energy (K(u)) with thickness dependence shows a change of magnetic-easy-axis direction from perpendicular to in-plane around 1.2 nm of CoZr. The interfacial anisotropy (K(i)) as the directly related parameters to switching and thermal stability, are estimated as 1.64 erg/cm2 from CoZr/Pt multilayered system.

  2. Energy loss straggling data of 28Si, 27Al, 24Mg, 19F, 16O, and 12C heavy ions in thin polymeric Formvar foil over a range of energies 0.1-0.6 MeV/u by time-of-flight spectrometry

    Science.gov (United States)

    Guesmia, A.; Ammi, H.; Msimanga, M.; Dib, A.; Mammeri, S.; Pineda-Vargas, C. A.; Hedibel, M.

    2015-02-01

    The energy-loss straggling of 28Si, 27Al, 24Mg, 19F, 16O and 12C partially stripped heavy ions has been determined in Formvar polymeric thin foil over a continuous range of energies 0.1-0.6 MeV/u, by using a powerful method based on the combination of Heavy Ion-Elastic Recoil Detection Analysis (HI-ERDA) technique and Time of Flight (ToF) spectrometer. The obtained energy loss straggling values have been analyzed and compared with the corresponding computed values adopting some widely used energy loss straggling formulations such as, Bohr, Bethe-Livingston and Yang formulas. The aim of such a comparison is to check the reliability and accuracy of the existing energy loss straggling formulations. The experimental results of energy loss straggling of all ions are found to be significantly greater than those predicted by the theories. These differences can be attributed to the charge exchange straggling. This effect has to be taken into account in order to explain the obtained results.

  3. Differential cross section measurements of {sup 27}Al(p,p{sup /}γ){sup 27}Al and {sup 27}Al(p,αγ){sup 24}Mg reactions in the energy range of 1.6–3.0 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Jokar, A., E-mail: arezajokar@gmail.com [Physics & Accelerators Research School, NSTRI, PO Box 14395-836, Tehran (Iran, Islamic Republic of); Kakuee, O.; Lamehi-Rachti, M. [Physics & Accelerators Research School, NSTRI, PO Box 14395-836, Tehran (Iran, Islamic Republic of); Sharifzadeh, N. [Payame Noor University, PO Box 19395-13697, Tehran (Iran, Islamic Republic of); Fathollahi, V. [Physics & Accelerators Research School, NSTRI, PO Box 14395-836, Tehran (Iran, Islamic Republic of)

    2015-11-01

    In this work measurement of differential cross sections of {sup 27}Al(p,p{sup /}γ){sup 27}Al (E{sub γ} = 844, 1014 keV) and {sup 27}Al(p,αγ){sup 24}Mg (E{sub γ} = 1369 keV) nuclear reactions in the proton energy range of 1.6–3.0 MeV are described and the measured values are presented. Thin Al target was prepared by evaporating a 26 μg/cm{sup 2} Al onto a 129 μg/cm{sup 2} self-supporting Ag film. The gamma-rays and backscattered protons were detected simultaneously. The gamma-rays and protons were collected by an HPGe detector placed at an angle of 90° with respect to beam direction and an ion implanted Si detector placed at a scattering angle of 165°, respectively. In this experimental setup the great advantage is that differential cross sections could be independent on absolute values of the collected beam charge. The overall systematic uncertainty of cross sections was estimated to be ±9% while statistical errors were less than ±5%.

  4. Flow and multifragmentation of $^{24}$Mg + $^{27}$Al at intermediate energies

    NARCIS (Netherlands)

    Prendergast, E. P.; Brink, A. van der; Haas, A. P. de; Kamermans, R.; Kuijer, P. G.; Laat, C. T. A. M. de; Ostendorf, R. W.; Oti, E.; Péghaire, A.; Snellings, R. J. M.

    1999-01-01

    Submitted to: Phys. Rev. C Abstract: An elaborated investigation was done into the reaction mechanism of heavy ion collisions at intermediate energies of small nuclear systems. Experimental data measured with the Huygens detectors and IQMD simulations of mgal at 45 and 95 amev were analysed with res

  5. Comparison between cross sections, saddle point and scission point barriers for the {sup 32}S+{sup 24}Mg reaction

    Energy Technology Data Exchange (ETDEWEB)

    Santos, T.J.; Carlson, B.V., E-mail: nztiago@gmail.com [Instituto Tecnologia de Aeronautica (ITA), Sao Jose dos Campos, SP (Brazil)

    2014-07-01

    One of the principal characteristics of nuclear multifragmentation is the emission of complex fragments of intermediate mass. The statistical multifragmentation model has been used for many years to describe the distribution of these fragments. An extension of the statistical multifragmentation model to include partial widths and lifetimes for emission, interprets the fragmentation process as the near simultaneous limit of a series of sequential binary decays. In this extension, the expression describing intermediate mass fragment emission is almost identical to that of light particle emission. At lower temperatures, similar expressions have been shown to furnish a good description of very light intermediate mass fragment emission. However, this is usually not considered a good approximation to the emission of heavier fragments. These emissions seem to be determined by the characteristics of the system at the saddle-point and its subsequent dynamical evolution rather than by the scission point. Here, we compare the barriers and decay widths of these different formulations of intermediate fragment emission and analyze the extent to which they remain distinguishable at high excitation energy. (author)

  6. Analysis of Deuteron-Nucleus Scattering Using Sao Paulo Potential

    Science.gov (United States)

    Ibraheem, Awad A.

    2016-12-01

    Deuteron elastic and inelastic scattering from 6Li, 12C, 16O, 24Mg, 32S, 50V, 58Ni, 70Ge, 90Zr, and 116Sn targets at different incident energies have been analyzed. Both Phenomenological Woods-Saxon and double-folding optical model potentials have been used. The folding calculations were based upon the Sao Paulo potential. A semi-microscopic representation has been proposed to study the effect of the dynamic polarization potential. Comparisons between our results and measured angular distributions of the differential cross sections showed a pronounced success of our theoretical predictions. The corresponding reaction cross sections have also been investigated.

  7. Stellar 30-keV neutron capture in 94,96Zr and the 90Zr(gamma,n)89Zr photonuclear reaction with a high-power liquid-lithium target

    CERN Document Server

    Tessler, M; Arenshtam, A; Feinberg, G; Friedman, M; Halfon, S; Kijel, D; Weissman, L; Aviv, O; Berkovits, D; Eisen, Y; Eliyahu, I; Haquin, G; Kreisel, A; Mardor, I; Shimel, G; Shor, A; Silverman, I; Yungrais, Z

    2015-01-01

    A high-power Liquid-Lithium Target (LiLiT) was used for the first time for neutron production via the thick-target 7Li(p,n)7Be reaction and quantitative determination of neutron capture cross sections. Bombarded with a 1-2 mA proton beam at 1.92 MeV from the Soreq Applied Research Accelerator Facility (SARAF), the setup yields a 30-keV quasi-Maxwellian neutron spectrum with an intensity of 3-5e10 n/s, more than one order of magnitude larger than present near-threshold 7Li(p,n) neutron sources. The setup was used here to determine the 30-keV Maxwellian averaged cross section (MACS) of 94Zr and 96Zr as 28.0+-0.6 mb and 12.4+-0.5 mb respectively, based on activation measurements. The precision of the cross section determinations results both from the high neutron yield and from detailed simulations of the entire experimental setup. We plan to extend our experimental studies to low-abundance and radioactive targets. In addition, we show here that the setup yields intense high-energy (17.6 and 14.6 MeV) prompt cap...

  8. The nuclear spin response to intermediate energy protons

    Energy Technology Data Exchange (ETDEWEB)

    Baker, F.T. (Georgia Univ., Athens (USA)); Bimbot, L.; Djalali, C.; Morlet, M.; Willis, A. (Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire); Castel, B. (Queen' s Univ., Kingston, Ontario (Canada)); Fergerson, R.W.; Glashausser, C.; Green, A.; Beatty, D.; Cupps, V. (Rutgers - the State Univ., Piscataway, NJ (USA)); Hausser, O. (Simon Fraser Univ., Burnaby, British Columbia (Canada) British Columbia Univ., Vancouver (Canada). TRIUMF Facility); Hicks, K.; Miller, C.A.; Abegg, R.; Jackson, K.P.; Yen, S. (British Columbia Univ., Vancouver (Canada). TRIUMF Facility); Jones, K.; Smith, R.D. (Los Alamos National Lab., NM (USA)); Nanda, S.K. (Continuous Electron Beam Accelerator Facility, Newport News, VA (USA)); Vetterli, M.; Jeppeson, R. (Simon Fraser Univ., Burnaby, British Columbia (Canada)); Henderson, R. (British Columbia Univ., Vancouver (Canada). TRIUMF Facility Melbourne Univ., Parkville (Australia)); Lisantti, J. (Oregon Univ., Eugene (USA)); Sawafta, R. (A

    1990-03-22

    Measurements of the spin-flip probability S{sub nn} for inclusive inelastic proton scattering around 300 MeV from nuclei between {sup 12}C and {sup 90}Zr show that an enhanced spin response near 40 MeV excitation at q{proportional to}100 MeV/c is a general feature of nuclear structure. Data for {sup 40}Ca at 800 MeV confirm that the enhancement is not a peculiarity of 300 MeV scattering. In addition, measurements in {sup 44}Ca up to 75 MeV show that the enhancement cannot be attributed solely to a relatively narrow resonance. Continuum RPA calculations suggest that the enhancement is due to the exhaustion of most S=0 strength at lower energy and a shift of S=1 strength to higher energy. (orig.).

  9. Measurement of the spin-forbidden decay rate (3s3d)1D2¿(3s3p)3 P2,1 in 24Mg

    DEFF Research Database (Denmark)

    Therkildsen, K. T.; Jensen, Brian Bak; Ryder, C. P.;

    2009-01-01

    We have measured the spin-forbidden decay rate from (3s3d)D12¿(3s3p)P32,1 in M24g atoms trapped in a magneto-optical trap. The total decay rate, summing up both exit channels (3s3p)P31 and (3s3p)P32 , yields 196±10s-1 in excellent agreement with resent relativistic many-body calculations of Porsev...

  10. Clustering effects in fusion evaporation reactions with light even-even N=Z nuclei. The 24Mg and 28Si cases

    Directory of Open Access Journals (Sweden)

    Morelli L.

    2016-01-01

    Inclusive variables are in general well reproduced by the model. We found clear deviations from the statistical model if we select emission channels involving multiple α particles which are more probable than expected from a purely statistical behavior. Data from 12C+12C reaction have been analyzed in order to study the decay of the Hoyle state of 12C* with two different selections: peripheral binary collisions and 6α decay channel in central events. To continue the investigation on light systems, we have recently measured the 16O+12C reaction at three different beam energies, namely Ebeam = 90, 110 and 130 MeV. Preliminary results are presented.

  11. Modelización de la hidroquímica y sedimentoquímica de una laguna tipo playa (Cl- So2-4 Mg2+ - Na+: La Laguna Grande de Quero (Toledo

    Directory of Open Access Journals (Sweden)

    García del Cura, M. A.

    1991-08-01

    Full Text Available The «Laguna Grande de Quero», is a saline pond located on the aluvial system from the Cigüela and Riansares rivers. The pond's underground impermeable materials are claystone with gypsum from the Triassic ages. On the next reliefs appears gypsiferous-detrital and calcareous materials from the Tertiary ages. A model have been created for the evaporative process, correcting the saline effect bearing in mind the climatic parameters; the conclusions obtained are coherents with the experimental data, which have been obtained in two experimental pools placed for the evaporative- concentration processes chasing. The experimental precipitation sequence obtained was: calcite + gypsum → bloedite + thenardite → bloedite → epsomite + halite. This sequence has been studied about saits generated on the air-brine interface. Moreover coincide with the foreseeable theoric sequence, according to Valyashko diagrams. In the natural environment appears facies and paragenesis associations coherents with the experimental data. During the evaporative process to specific gravity and concentration evolution graphics show a stagnancy period, «plateau effect», that it seams to coincide with a differential heating from the depth waters. The explanation of this effect can be related with the salts dissolution previously formed.La Laguna Grande de Quero, se ubica en el sistema aluvial de los ríos Cigüela-Riansares. Los materiales del subsuelo impermeable de la laguna son lutitas con yeso del Trías. En los relieves próximos afloran materiales detrítico-yesíferos y calcáreos de edad Terciaria. Se ha establecido un modelo del proceso de evaporación, corrigiendo el efecto salino, y teniendo en cuenta los parámetros climáticos, obteniendo resultados coherentes con los datos obtenidos en las balsas experimentales instaladas para el seguimiento del proceso de evaporación-concentración de la salmuera. La secuencia de precipitación experimental obtenida ha sido: calcita + yeso → bloedita + thenardita → bloedita → epsomita + halita. Esta secuencia se ha estudiado sobre fases salinas generadas en la interfase salmuera-aire. Además coincide con las secuencias teóricas previsibles según los diagramas de Valyashko. En el medio natural aparecen asociaciones de facies y paragénesis coherentes con los datos experimentales. Durante el proceso de evaporación, las curvas de evolución de la densidad y concentración presentan períodos de estancamiento («efecto meseta» que parecen coincidir con un calentamiento diferencial de las aguas del fondo. La explicación de este efecto puede estar en relación con la disolución de fases salinas previamente formadas.

  12. Trace isotope analysis of Ricinus communis seed core for provenance determination by laser ablation-ICP-MS.

    Science.gov (United States)

    Bagas, Christina K; Scadding, Rachel L; Scadding, Cameron J; Watling, R John; Roberts, Warren; Ovenden, Simon P B

    2017-01-01

    The castor bean plant, Ricinus communis, grows wild throughout many regions of Australia. The seeds of the plant contain the schedule 1 chemical agent ricin, a type II ribosomal inhibiting protein. Currently there are limited analytical techniques that can be applied in analysis of the seeds to establish attribution. In this study, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used for the analysis of seeds collected from 68 plants across 38 locations around Australia. Of the 92 elemental isotopes measured, fifteen ((24)Mg, (27)Al, (44)Ca, (53)Cr, (55)Mn, (57)Fe, (60)Ni, (65)Cu, (66)Zn, (75)As, (85)Rb, (88)Sr, (98)Mo, (138)Ba and (202)Hg) yielded data that were relevant to all collection sites. Data were further analysed using multivariate statistical analysis which facilitated the potential for the identification of unique provenance isotopes. Furthermore, this analysis indicated that (59)Co was present at significant levels in Victorian and Sydney specimens only.

  13. Isotopic fractionation of Mg 2+(aq), Ca 2+(aq), and Fe 2+(aq) with carbonate minerals

    Science.gov (United States)

    Rustad, James R.; Casey, William H.; Yin, Qing-Zhu; Bylaska, Eric J.; Felmy, Andrew R.; Bogatko, Stuart A.; Jackson, Virgil E.; Dixon, David A.

    2010-11-01

    Density-functional electronic structure calculations are used to compute the equilibrium constants for 26Mg/ 24Mg and 44Ca/ 40Ca isotope exchange between carbonate minerals and uncomplexed divalent aquo ions. The most reliable calculations at the B3LYP/6-311++G(2d,2p) level predict equilibrium constants K, reported as 10 3ln ( K) at 25 °C, of -5.3, -1.1, and +1.2 for 26Mg/ 24Mg exchange between calcite (CaCO 3), magnesite (MgCO 3), and dolomite (Ca 0.5Mg 0.5CO 3), respectively, and Mg 2+(aq), with positive values indicating enrichment of the heavy isotope in the mineral phase. For 44Ca/ 40Ca exchange between calcite and Ca 2+(aq) at 25 °C, the calculations predict values of +1.5 for Ca 2+(aq) in 6-fold coordination and +4.1 for Ca 2+(aq) in 7-fold coordination. We find that the reduced partition function ratios can be reliably computed from systems as small as M(CO)610- and M(HO)62+ embedded in a set of fixed atoms representing the second-shell (and greater) coordination environment. We find that the aqueous cluster representing the aquo ion is much more sensitive to improvements in the basis set than the calculations on the mineral systems, and that fractionation factors should be computed using the best possible basis set for the aquo complex, even if the reduced partition function ratio calculated with the same basis set is not available for the mineral system. The new calculations show that the previous discrepancies between theory and experiment for Fe 3+-hematite and Fe 2+-siderite fractionations arise from an insufficiently accurate reduced partition function ratio for the Fe 3+(aq) and Fe 2+(aq) species.

  14. Isotopic Fractionation of Mg2+(aq), Ca2+(aq), and Fe2+(aq) with Carbonate Minerals

    Energy Technology Data Exchange (ETDEWEB)

    Rustad, James R.; Casey, William H.; Yin, Qing-Zhu; Bylaska, Eric J.; Felmy, Andrew R.; Bogatko, Stuart A.; Jackson, Virgil E.; Dixon, David A.

    2010-11-15

    Density functional electronic structure calculations are used to compute the equilibrium constant (the isotope fractionation factor) for 26Mg/24Mg and 44Ca/40Ca isotope exchange between carbonate minerals and uncomplexed divalent aquo ions. The most reliable calculations at the B3LYP/6-311++G(2d,2p) level predict equilibrium constants K, reported as 103ln(K) at 25 °C, of -5.3, -1.1, and +1.1 for 26Mg/24Mg exchange between calcite (CaCO3), magnesite (MgCO3), and dolomite (Ca0.5Mg0.5CO3), respectively, and Mg2+(aq), with positive values indicating enrichment in the mineral phase. For 44Ca/40Ca exchange between calcite and Ca2+(aq), the calculations predict values of +1.5 for Ca2+(aq) in six-fold coordination and +4.1 for Ca2+(aq) in seven-fold coordination. We find that the reduced partition function ratios can be reliably computed from systems as small as M(CO3)610- and M2+(H2O)6 embedded in a set of fixed atoms representing the 2nd shell (and greater) coordination environment. We find that the aqueous cluster representing the aquo ion is much more sensitive to improvements in the basis set than the calculations on the mineral systems, and that fractionation factors should be computed using 2 the best possible basis set for the aquo complex, even if the reduced partition function ratio calculated with the same basis set is not available for the mineral system. The new calculations show that the previous discrepancies between theory and experiment for Fe3+-hematite and Fe2+-siderite fractionations arise from an insufficiently accurate reduced partition function ratio for the Fe3+(aq) and Fe2+(aq) species.

  15. Chemical and Charge Imbalance Induced by Radionuclide Decay: Effects on Waste Form Structure

    Energy Technology Data Exchange (ETDEWEB)

    Van Ginhoven, Renee M.; Jaffe, John E.; Jiang, Weilin; Strachan, Denis M.

    2011-04-01

    This is a milestone document covering the activities to validate theoretical calculations with experimental data for the effect of the decay of 90Sr to 90Zr on materials properties. This was done for a surragate waste form strontium titanate.

  16. Evaluation Study for the Production of the Medical Isotope ^90Y, using a Cyclotron

    Science.gov (United States)

    Necsoiu, D.; Morgan, I. L.; Hupf, Homer; Armbruster, J.; Boyce, D.; El Bouanani, M.; McDaniel, F. D.

    2000-10-01

    The use of radioisotopes in therapy, medical imaging and laboratory tests is well-established worldwide. ^90Y is a very good therapeutic candidate for radioimmunotherapy applications. Traditionally, medical radioisotopes are produced using either nuclear reactors or proton accelerators. In this study, the medical isotope ^90Y has been produced using ^90Zr(n,p)^90Y nuclear reaction. Neutrons for the activation process were produced using ^natRh(p,xn) reaction with a 27 MeV proton beam from a cyclotron. Since ^90Y is a pure beta emitter, the gamma rays from the ^90Zr(n,2n)^89Zr reaction were used to quantify the incident neutron flux on the ^90Zr sample. Experimental results of the neutron production and ^90Y activity are presented.

  17. Improved Quantum Molecular Dynamics Model and its Application to Fusion Reaction Near Barrier

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An improved quantum molecular dynamics model is proposed. By using this model, the properties of ground state of nuclei from 6Li to 208Pb can be described very well with one set of parameters. The fusion reactions for 40Ca+90Zr, 40Ca+96Zr and 48Ca+90Zr at the energy near the barrier are studied by this model. The experimental data of the fusion cross sections for 40Ca+90,96Zr at the energy near the barrier can be reproduced remarkably well without introducing any new parameters. The mechanism

  18. The Brieva-Rook Localization of the Microscopic Nucleon-Nucleus Potential

    CERN Document Server

    Minomo, K; Kohno, M; Shimizu, Y R; Yahiro, M

    2009-01-01

    The nonlocality of the microscopic nucleon-nucleus optical potential is commonly localized by the Brieva-Rook approximation. The validity of the localization is tested for the proton+$^{90}$Zr scattering at the incident energies from 65 MeV to 800 MeV. The localization is valid in the wide incident-energy range.

  19. Decay Properties Of The Dipole Isobaric Analog Resonances

    NARCIS (Netherlands)

    Gorelik, M. L.; Safonov, I. V.; Urin, M. H.

    2006-01-01

    Abstract: A continuum-RPA-based approach is applied to describe the decay properties of isolated dipole isobaric analog resonances in nuclei having not-too-large neutron excess. Calculated for a few resonances in 90Zr the elastic E1-radiative width and partial proton widths for decay into one-hole s

  20. Plausible domain configurations and phase contents in two- and three-phase BaTiO3-based lead-free ferroelectrics

    Science.gov (United States)

    Topolov, Vitaly Yu; Brajesh, Kumar; Ranjan, Rajeev; Panich, Anatoly E.

    2017-02-01

    We have carried out a comparative study of plausible non-180° domain configurations in the two- and three-phase states of lead-free ferroelectrics Ba(Ti1-x Zr x )O3 (0.02  ⩽  x  ⩽  0.08) and (Ba0.85Ca0.15)(Ti0.90Zr0.10)O3, respectively, using the elastic matching approach. The phase contents and stress-relief conditions in Ba(Ti0.93Zr0.07)O3 and (Ba0.85Ca0.15)(Ti0.90Zr0.10)O3 strongly depend on domain types in the rhombohedral R3m phase, whereas domains of the orthorhombic Amm2 phase influence two-phase states in Ba(Ti0.98Zr0.02)O3. Changes in unit-cell parameters of (Ba0.85Ca0.15)(Ti0.90Zr0.10)O3 at poling lead to the complete stress relief in three-phase (P4mm  +  Amm2  +  R3m) structures by increasing the volume fraction of the R3m phase. A link between the heterophase/domain structures and high piezoelectric activity in (Ba0.85Ca0.15)(Ti0.90Zr0.10)O3 is discussed. Based on our results, we state that equal or almost equal volume fractions of the domain types at the three-phase coexistence in (Ba0.85Ca0.15). .(Ti0.90Zr0.10)O3 can lead to an enhanced contribution from domain-wall displacements and therefore, to the large piezoelectric response in this important lead-free ferroelectric compound.

  1. The PSIMECX medium-energy neutron activation cross-section library. Part II: Calculational methods for light to medium mass nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Atchison, F.

    1998-09-01

    The PSIMECX library contains calculated nuclide production cross-sections from neutron-induced reactions in the energy range about 2 to 800 MeV in the following 72 stable isotopes of 24 elements: {sup 12}C, {sup 13}C, {sup 16}O, {sup 17}O, {sup 18}O, {sup 23}Na, {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 27}Al, {sup 28}Si, {sup 29}Si, {sup 30}Si, {sup 31}P, {sup 32}S, {sup 33}S, {sup 34}S, {sup 36}S, {sup 35}Cl, {sup 37}Cl, {sup 39}K, {sup 40}K, {sup 41}K, {sup 40}Ca, {sup 42}Ca, {sup 43}Ca, {sup 44}Ca, {sup 46}Ca, {sup 48}Ca, {sup 46}Ti, {sup 47}Ti, {sup 48}Ti, {sup 49}Ti, {sup 50}Ti, {sup 50}V, {sup 51}V, {sup 50}Cr, {sup 52}Cr, {sup 53}Cr, {sup 54}Cr, {sup 55}Mn, {sup 54}Fe, {sup 56}Fe, {sup 57}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 61}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 66}Zn, {sup 67}Zn, {sup 68}Zn, {sup 70}Zn, {sup 92}Mo, {sup 94}Mo, {sup 95}Mo, {sup 96}Mo, {sup 97}Mo, {sup 98}Mo, {sup 100}Mo, {sup 121}Sb, {sup 123}Sb, {sup 204}Pb, {sup 206}Pb, {sup 207}Pb, {sup 208}Pb, {sup 232}Th and {sup 238}U. The energy range covers essentially all transmutation channels other than capture. The majority of the selected elements are principal constituents of normal materials of construction used in and around accelerator facilities and the library is, first and foremost, designed to be a tool for the estimation of their activation in wide-band neutron fields. This second report, of a series of three, describes and discusses the calculational methods used for the stable isotopes up to and including {sup 123}Sb. The library itself has been described in the first report of the series and the treatment for the heavy nuclei is given in the third. (author)

  2. The PSIMECX medium-energy neutron activation cross-section library. Part 1: Description and procedures for use

    Energy Technology Data Exchange (ETDEWEB)

    Atchison, F.

    1998-09-01

    The PSIMECX library contains calculated nuclide production cross-sections from neutron-induced reactions in the energy range about 2 to 800 MeV in the following 72 stable isotopes of 24 elements: {sup 12}C, {sup 13}C, {sup 16}O, {sup 17}O, {sup 18}O, {sup 23}Na, {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 27}Al, {sup 28}Si, {sup 29}Si, {sup 30}Si, {sup 31}P, {sup 32}S, {sup 33}S, {sup 34}S, {sup 36}S, {sup 35}Cl, {sup 37}Cl, {sup 39}K, {sup 40}K, {sup 41}K, {sup 40}Ca, {sup 42}Ca, {sup 43}Ca, {sup 44}Ca, {sup 46}Ca, {sup 48}Ca, {sup 46}Ti, {sup 47}Ti, {sup 48}Ti, {sup 49}Ti, {sup 50}Ti, {sup 50}V, {sup 51}V, {sup 50}Cr, {sup 52}Cr, {sup 53}Cr, {sup 54}Cr, {sup 55}Mn, {sup 54}Fe, {sup 56}Fe, {sup 57}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 61}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 66}Zn, {sup 67}Zn, {sup 68}Zn, {sup 70}Zn, {sup 92}Mo, {sup 94}Mo, {sup 95}Mo, {sup 96}Mo, {sup 97}Mo, {sup 98}Mo, {sup 100}Mo, {sup 121}Sb, {sup 123}Sb, {sup 204}Pb, {sup 206}Pb, {sup 207}Pb, {sup 208}Pb, {sup 232}Th and {sup 238}U. The energy range covers essentially all transmutation channels other than capture. The majority of the selected elements are principal constituents of normal materials of construction used in and around accelerator facilities and the library is, first and foremost, designed to be a tool for the estimation of their activation in wide-band neutron fields. This first report, from a set of three, describes the form and usage of the library; the other two reports document the calculational methods. The present organisation of the library is the author's first idea and adequate for the intended use (activation calculations); being machine readable, translation of the library into other formats is straightforward. (author)

  3. CORRELATION OF {sup 48}Ca, {sup 50}Ti, AND {sup 138}La HETEROGENEITY IN THE ALLENDE REFRACTORY INCLUSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hsin-Wei; Lee, Typhoon; Lee, Der-Chuen; Chen, Jiang-Chang, E-mail: hart.chen@bristol.ac.uk [Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan, ROC (China)

    2015-06-10

    Precise determinations of {sup 48}Ca anomalies in Allende calcium–aluminum-rich inclusions (CAIs) are reported in this work. There are endemic positive {sup 48}Ca/{sup 44}Ca anomalies in all analyzed CAIs after normalization to {sup 42}Ca/{sup 44}Ca, and it is clearly shown that there is no simple correlation between {sup 48}Ca/{sup 44}Ca and {sup 50}Ti/{sup 48}Ti anomalies, in agreement with Jungck et al. Compared to the {sup 48}Ca/{sup 44}Ca versus {sup 50}Ti/{sup 48}Ti correlation line defined by differentiated meteorites, reported by Chen et al., the CAIs plot to elevated {sup 50}Ti/{sup 48}Ti. Assuming the {sup 48}Ca/{sup 44}Ca anomalies of both CAIs and differentiated meteorites came from the same source, excess {sup 50}Ti anomalies in CAIs can be calculated by subtracting the part associated with {sup 48}Ca/{sup 44}Ca. These excesses show a linear correlation with {sup 138}La anomalies, a neutrino-process nuclide. According to current stellar nucleosynthetic models, we therefore suggest that the solar system {sup 48}Ca, {sup 50}Ti, and {sup 138}La isotopic variations are made of mixtures between grains condensed from ejecta of neutron-rich accretion-induced SNe Ia and the O/Ne–O/C zone of core-collapse SNe II.

  4. Nuclear two-photon decay in 0 +→0 + transitions

    Science.gov (United States)

    Kramp, J.; Habs, D.; Kroth, R.; Music, M.; Schirmer, J.; Schwalm, D.; Broude, C.

    1987-11-01

    The two-photon decay of the first excited 0 + state of 16O has been measured using the Heidelberg-Darmstadt crystal ball. A branching ratio of {Γ γγ}/{Γ tot} = (6.6±0.5) · 10 -4 was obtained. As in the cases of 40Ca and 90Zr previously reported by us, the 2γ decay of 16O proceeds via double E1 and M1 transitions of similar strength; the evidence is the observed interference term in the 2γ angular correlation. The ratio of the matrix elements {α E1 }/{χ} for 16O was restricted to the two inverse values (-6.2±1.5) or (-0.16±0.04). An interpretation of 2γ matrix elements observed for 16O, 40Ca and 90Zr in terms of the electric polarizabilities and magnetic susceptibility is given leading to a qualitative understanding of this decay mode.

  5. Application of Multiple Scattering Theory to Lower Energy Elastic Nucleon-Nucleus Reactions

    OpenAIRE

    Chinn, C. R.; Elster, Ch.; Thaler, R. M.; Weppner, S. P.

    1994-01-01

    The optical model potentials for nucleon-nucleus elastic scattering at $65$~MeV are calculated for $^{12}$C, $^{16}$O, $^{28}$Si, $^{40}$Ca, $^{56}$Fe, $^{90}$Zr and $^{208}$Pb in first order multiple scattering theory, following the prescription of the spectator expansion, where the only inputs are the free NN potentials, the nuclear densities and the nuclear mean field as derived from microscopic nuclear structure calculations. These potentials are used to predict differential cross section...

  6. Contribution to the spectroscopy of 50 neutron isotones; Contribution a la spectroscopie des isotones a 50 neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Picard, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-05-01

    Proton states in the isotones N = 50 have been studied through the reaction ({sup 3}He,d) on {sup 88}Sr, {sup 90}Zr and {sup 92}Mo target nuclei with 18 MeV {sup 3}He projectiles and also neutron hole states using the ({sup 3}He,{alpha}) reaction on the same target. The information thus obtained on independent quasi-particle or hole states completes the set of experimental data required for a microscopic description of the collective properties of the even isotones {sup 88}Sr, {sup 90}Zr and {sup 92}Mo in the framework of BCS(IGE) + RPA theories. The results of this calculation are compared to experimental data and, more particularly, the results of 20 MeV proton inelastic scattering on {sup 88}Sr are analysed using anti-symmetrized DWBA with the microscopic wave functions calculated previously. (author) [French] Les etats de proton des isotones a 50 neutrons sont etudies par la reaction directe ({sup 3}He,d) sur les noyaux {sup 88}Sr, {sup 90}Zr et {sup 92}Mo avec des projectiles {sup 3}He de 18 MeV d'energie; ainsi que les etats de trou de neutron au moyen de la reaction directe ({sup 3}He,{alpha}) sur les memes cibles. L'information ainsi obtenue sur ces etats de trou ou de quasiparticule independante complete l'ensemble des donnees necessaire pour une description microscopique des proprietes collectives des isotones pairs {sup 88}Sr, {sup 90}Zr et {sup 92}Mo dans le cadre des modeles BCS(IGE) + RPA. Les resultats de ce calcul sont compares a l'experience et, en particulier, les resultats de la diffusion inelastique {sup 88}Sr(p,p'){sup 88}Sr{sup *} avec des protons de 20 MeV sont analyses dans un formalisme antisymetrise de la DWBA utilisant les fonctions d'onde microscopiques calculees precedemment. (auteur)

  7. First results of the EXILL and FATIMA campaign at the Institut Laue Langevin

    Energy Technology Data Exchange (ETDEWEB)

    Jolie, Jan; Regis, Jean-Marc; Saed-Samii, Nima; Warr, Nigel [IKP, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany); Wilmsen, Dennis [IKP, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany); GANIL, BP 55027 (France); France, Gilles de; Clement, Emmanuel [GANIL, BP 55027 (France); Blanc, Aurelien; Jentschel, Michael; Koester, Uli; Mutti, Paolo; Soldner, Thorsten [ILL, 71 Av. des Martyrs, 38042 Grenoble (France); Simpson, Gary [University of Western Scotland, Paisley, PA1 2BE (United Kingdom); UIrban, Waldek [Faculty of Physics, University of Warsaw, 02-093 Warsaw (Poland); Bruce, Alison; Lalskovski, Stefan [SCEM, University of Brighton, Brighton BN2 4GJ (United Kingdom); Fraile, Luis [Grupo de Fisica Nuclear, Universidad Complutese, 28040 Madrid (Spain); Kroell, Thorsten [Institut fuer Kernphysik, TU Darmstadt, Darmstadt (Germany); Podolyak, Zsolt; Regan, Patrick [Dept. of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Korten, Wolfram [CEA, Centre de Saclay, IRFU, 91191 Gif-sur-Yvette (France); Ur, Calin; Marginean, Nicu [Horia Hulubei NIPNE, 77125 Bucharest (Romania)

    2015-07-01

    At the PF1B cold neutron beam line at the Institut Laue Langevin the EXILL and FATIMA array consisting of 8 EXOGAM clover Ge detectors and 16 LaBr3(Ce) scintillators was used for the measurement of lifetimes using the generalised centroid difference method. The studied nuclei were formed by the (n,γ) and (n,fission) reactions. We report on the set-up and present first results on {sup 90}Zr and {sup 196}Pt.

  8. Microscopic Calculation of Total Ordinary Muon Capture Rates for Medium-weight and Heavy Nuclei

    CERN Document Server

    Kuzmin, V A; Junker, K; Ovchinnikova, A A

    2002-01-01

    Total Ordinary Muon Capture (OMC) rates are calculated on the basis of the Quasiparticle Random Phase Approximation for several spherical nuclei from 90^Zr to 208^Pb. It is shown that total OMC rates calculated with the free value of the axial-vector coupling constant g_A agree well with the experimental data for medium-size nuclei and exceed considerably the experimental rates for heavy nuclei. The sensitivity of theoretical OMC rates to the nuclear residual interactions is discussed.

  9. Enhanced population of side band of {sup 155}Gd in heavy-ion Coulomb excitation

    Energy Technology Data Exchange (ETDEWEB)

    Oshima, Masumi; Hayakawa, Takehito; Hatsukawa, Yuichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    1998-03-01

    In the Coulomb excitation of {sup 155}Gd with heavy projectiles, {sup 32}S, {sup 58}Ni and {sup 90}Zr, unexpectedly large enhancement of a positive-parity side band has been observed. This enhancement could not be reproduced by a Coulomb-excitation calculation taking into account the recommended upper limits of E1 or E3 transitions, which are compiled in the whole mass region, and is proportional to the electric field accomplished in the Coulomb-scattering process. (author)

  10. Enhanced population of side band of {sup 155}Gd in heavy-ion Coulomb excitation

    Energy Technology Data Exchange (ETDEWEB)

    Oshima, Masumi; Hayakawa, Takehito; Hatsukawa, Yuichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    1998-03-01

    In the Coulomb excitation of {sup 155}Gd with heavy projectiles, {sup 32}S, {sup 58}Ni and {sup 90}Zr, unexpectedly large enhancement of a positive-parity side band has been observed. This enhancement could not be reproduced by a Coulomb-excitation calculation taking into account the recommended upper limits of E1 or E3 transitions, which are compiled in the whole mass region, and is proportional to the electric field accomplished in the Coulomb-scattering process. (author)

  11. Technical Note: Calcium and carbon stable isotope ratios as paleodietary indicators.

    Science.gov (United States)

    Melin, Amanda D; Crowley, Brooke E; Brown, Shaun T; Wheatley, Patrick V; Moritz, Gillian L; Yit Yu, Fred Tuh; Bernard, Henry; DePaolo, Donald J; Jacobson, Andrew D; Dominy, Nathaniel J

    2014-08-01

    Calcium stable isotope ratios are hypothesized to vary as a function of trophic level. This premise raises the possibility of using calcium stable isotope ratios to study the dietary behaviors of fossil taxa and to test competing hypotheses on the adaptive origins of euprimates. To explore this concept, we measured the stable isotope composition of contemporary mammals in northern Borneo and northwestern Costa Rica, two communities with functional or phylogenetic relevance to primate origins. We found that bone collagen δ(13) C and δ(15) N values could differentiate trophic levels in each assemblage, a result that justifies the use of these systems to test the predicted inverse relationship between bioapatite δ(13) C and δ(44) Ca values. As expected, taxonomic carnivores (felids) showed a combination of high δ(13) C and low δ(44) Ca values; however, the δ(44) Ca values of other faunivores were indistinguishable from those of primary consumers. We suggest that the trophic insensitivity of most bioapatite δ(44) Ca values is attributable to the negligible calcium content of arthropod prey. Although the present results are inconclusive, the tandem analysis of δ(44) Ca and δ(13) C values in fossils continues to hold promise for informing paleodietary studies and we highlight this potential by drawing attention to the stable isotope composition of the Early Eocene primate Cantius.

  12. New results in low-energy fusion of 40Ca+Zr,9290

    Science.gov (United States)

    Stefanini, A. M.; Montagnoli, G.; Esbensen, H.; Čolović, P.; Corradi, L.; Fioretto, E.; Galtarossa, F.; Goasduff, A.; Grebosz, J.; Haas, F.; Mazzocco, M.; Soić, N.; Strano, E.; Szilner, S.

    2017-07-01

    Background: Near- and sub-barrier fusion of various Ca + Zr isotopic combinations have been widely investigated. A recent analysis of 40Ca+96Zr data has highlighted the importance of couplings to multiphonon excitations and to both neutron and proton transfer channels. Analogous studies of 40Ca+90Zr tend to exclude any role of transfer couplings. However, the lowest measured cross section for this system is rather high (840 μ b ). A rather complete data set is available for 40Ca+94Zr , while no measurement of 40Ca+92Zr fusion has been performed in the past. Purpose: Our aim is to measure the full excitation function of 40Ca+92Zr near the barrier and to extend downward the existing data on 40Ca+90Zr , in order to estimate the transfer couplings that should be used in coupled-channels calculations of the fusion of these two systems and of 40Ca+94Zr . Methods: 40Ca beams from the XTU Tandem accelerator of INFN-Laboratori Nazionali di Legnaro were used, bombarding thin metallic 90Zr (50 μ g /cm2 ) and 92ZrO2 targets (same thickness) enriched to 99.36 % and 98.06 % in masses 90 and 92, respectively. An electrostatic beam deflector allowed the detection of fusion evaporation residues (ER) at very forward angles, and angular distributions of ER were measured. Results: The excitation function of 40Ca+92Zr has been measured down to the level of ≃60 μ b . Coupled-channels (CC) calculations using a standard Woods-Saxon (WS) potential and following the line of a previous analysis of 40Ca+96Zr fusion data give a good account of the new data, as well as of the existing data for 40Ca+94Zr . The previous excitation function of 40Ca+90Zr has been extended down to 40 μ b . Conclusions: Transfer couplings play an important role in explaining the fusion data for 40Ca+92Zr and 40Ca+94Zr . The strength of the pair-transfer coupling is deduced by applying a simple recipe based on the value obtained for 40Ca+96Zr . The logarithmic slopes and the S factors for fusion are reproduced

  13. Calcium isotope systematics in small upland catchments affected by spruce dieback in the period of extreme acid rain (1970-1990)

    Science.gov (United States)

    Novak, Martin; Farkas, Juraj; Holmden, Chris; Hruska, Jakub; Curik, Jan; Stepanova, Marketa; Prechova, Eva; Veselovsky, Frantisek; Komarek, Arnost

    2017-04-01

    Recently, new isotope tools have become available to study the behavior of nutrients in stressed ecosystems. In this study, we focus on changes in the abundance ratio of calcium (Ca) isotopes accompanying biogeochemical processes in small forested catchments. We monitored del44Ca values in ecosystem pools and fluxes in four upland sites situated in the Czech Republic, Central Europe. A heavily acidified site in the Eagle Mts. (northern Czech Republic) experienced 13 times higher atmospheric Ca inputs, compared to the other three sites, which were less affected by forest decline. Industrial dust was responsible for the elevated Ca input. Del44Ca values of individual poos/fluxes were used to identify Ca sources for the bioavailable Ca soil reservoir and for runoff. The bedrock of the study sites differed (leucogranite, orthogneiss vs. serpentinite and amphibolite). Across the sites, mean del44Ca values increased in the order: spruce bark < fine roots < needles < soil < bedrock < canopy throughfall < open-area precipitation < runoff < soil water. Plant preferentially took up isotopically light Ca, while residual isotopically heavy Ca was sorbed to soil particles or exported via runoff. Even at sites with a low del44Ca values of bedrock, runoff had a high del44Ca value. At the base-poor site, most runoff came from atmospheric deposition and residual Ca following plant uptake. It appeared that bedrock weathering did not supply enough Ca to replenish the bioavailable Ca pool in the soil. Currently, we are analyzing Ca isotope composition of individual rock-forming minerals to better assess the effect of different weathering rates of minerals with low/high radiogenic 40Ca contents on runoff del44Ca.

  14. Calculations of Compound Nucleus Spin-Parity Distributions Populated via the (p,t Reaction in Support of Surrogate Neutron Capture Measurements

    Directory of Open Access Journals (Sweden)

    Benstead J.

    2016-01-01

    Full Text Available The surrogate reaction method may be used to determine the cross section for neutron induced reactions not accessible through standard experimental techniques. This is achieved by creating the same compound nucleus as would be expected in the desired reaction, but through a different incident channel, generally a direct transfer reaction. So far, the surrogate technique has been applied with reasonable success to determine the fission cross section for a number of actinides, but has been less successful when applied to other reactions, e.g. neutron capture, due to a ‘spin-parity mismatch’. This mismatch, between the spin and parity distributions of the excited levels of the compound nucleus populated in the desired and surrogate channels, leads to differing decay probabilities and hence reduces the validity of using the surrogate method to infer the cross section in the desired channel. A greater theoretical understanding of the expected distribution of levels excited in both the desired and surrogate channels is therefore required in order to attempt to address this mismatch and allow the method to be utilised with greater confidence. Two neutron transfer reactions, e.g. (p,t, which allow the technique to be utilised for isotopes further removed from the line of stability, are the subject of this study. Results are presented for the calculated distribution of compound nucleus states populated in 90Zr, via the 90Zr(p,t90Zr reaction, and are compared against measured data at an incident proton energy of 28.56 MeV.

  15. Alpha decay of {sup 181}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Davids, C.N.; Henderson, D.J.; Hermann, R. [and others

    1995-08-01

    The {alpha}-decay energy of {sup 181}Pb was measured as 7211(10) keV and 7044(15). In the first study the isotope was produced in {sup 90}Zr bombardments of {sup 94}Mo and, after traversing a velocity filter, implanted in a position-sensitive Si detector; no half life for {sup 181}Pb was reported. In the second study the isotope was produced in {sup 40}Ca bombardments of {sup 144}Sm and transported to a position in front of a Si(Au) surface barrier detector with a fast He-gas-jet capillary system; an estimate of 50 ms was determined for the {sup 181}Pb half life. Recently we investigated {sup 181}Pb {alpha} decay at ATLAS as part of a survey experiment in which a l-pnA beam of 400-MeV {sup 92}Mo was used to irradiate targets of {sup 89}Y, {sup 90,92,94}Zr, and {sup 92}Mo to examine yields for one- and two-nucleon evaporation products from symmetric cold-fusion reactions. Recoiling nuclei of interest were passed through the Fragment Mass Analyzer and implanted in a double-sided silicon strip detector for {alpha}-particle assay. With the {sup 90}Zr target we observed a group at 7065(20) keV which was correlated with A = 181 recoils and had a half life of 45(20) ms. Our new results for {sup 181}Pb therefore agreed with those of the second study. There was no indication in the {sup 90}Zr + {sup 92}Mo data of the 7211(10)-keV {alpha} particles seen by Keller et al. The interested reader is referred to the 1993 atomic mass evaluation wherein the input {alpha}-decay energies and resultant masses of the light Pb isotopes (including {sup 181}Pb) are discussed.

  16. Optical and structural characterization of SrZr{sub 0,1}Ti{sub 0,9}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Delgado-Nino, Pilar [Laboratorio de Catalisis Heterogenea, Departamento de Quimica, Facultad de Ciencias, Universidad Nacional de Colombia, Bogota, D.C. (Colombia); Lopez-Rivera, S.A., E-mail: adan@ula.ve [Grupo de Fisica Aplicada, Facultad de Ciencias, Universidad de los Andes, Merida (Venezuela, Bolivarian Republic of); Mestres-Vila, Lourdes; Martinez-Sarrion, Maria Luisa [Departamento de Quimica Inorganica, Facultad de Quimica, Universitat de Barcelona, Barcelona, Espana (Spain); Valencia-Rios, Jesus S. [Laboratorio de Catalisis Heterogenea, Departamento de Quimica, Facultad de Ciencias, Universidad Nacional de Colombia, Bogota, D.C. (Colombia)

    2012-10-15

    In this work, the ceramic compound SrTi{sub 0.90}Zr{sub 0,1}O{sub 3} (SZT) was synthesized by the citrate method. This solid showed a 12 nm crystallite size, reflecting the high degree of crystallinity obtained by this synthesis route. Differential and gravimetric thermal analysis showed that the solid was formed from 520 Degree-Sign C; the chemical composition was determined by ICP-AES4, giving a stoichiometry corresponding to the SrTi{sub 0.90}Zr{sub 0.10}O{sub 3} formula, and proved to be compatible with the X-ray diffraction data, refined by the Rietveld method. The morphology was explored by means of SEM and TEM, finding a homogenous particles distribution, arranged in lumps, susceptible to density changes by sintering between 1000 Degree-Sign C and 1200 Degree-Sign C. The photoluminescence (PL) spectrum shows a band between 470 nm and 520 nm, corresponding to the Ti and Zr ions 3d electronic transition. The SZT crystal structure is tetragonal with space group I4/mcm, number (140). - Highlights: Black-Right-Pointing-Pointer The ceramic nano structured compound SrTi{sub 0.90}Zr{sub 0,1}O{sub 3} was synthesized by the citrate method. Black-Right-Pointing-Pointer Differential and gravimetric thermal analysis showed the right thermodynamical parameters Black-Right-Pointing-Pointer Good agreement between the crystal structure, group theory and the optical properties was obtained. Black-Right-Pointing-Pointer The sized and high crystallinity of the nanoparticules was confirmed by SEM and TEM. Black-Right-Pointing-Pointer Crystal structure is tetragonal with space group I4/mcm was found by X-ray and Rietveld refinement.

  17. Unitary version of the single-particle dispersive optical model and single-hole excitations in medium-heavy spherical nuclei

    Science.gov (United States)

    Kolomiytsev, G. V.; Igashov, S. Yu.; Urin, M. H.

    2017-07-01

    A unitary version of the single-particle dispersive optical model was proposed with the aim of applying it to describing high-energy single-hole excitations in medium-heavy mass nuclei. By considering the example of experimentally studied single-hole excitations in the 90Zr and 208Pb parent nuclei, the contribution of the fragmentation effect to the real part of the optical-model potential was estimated quantitatively in the framework of this version. The results obtained in this way were used to predict the properties of such excitations in the 132Sn parent nucleus.

  18. Beta decay studies of r-process nuclei at the National Superconducting Cyclotron Laboratory

    CERN Document Server

    Pereira, J; Arndt, O; Becerril, A; Elliot, T; Estrade, A; Galaviz, D; Hennrich, S; Hosmer, P; Kessler, R; Kratz, K L; Lorusso, G; Mantica, P F; Matos, M; Montes, F; Santi, P; Pfeiffer, B; Quinn, M; Schatz, H; Schertz, F; Schnorrenberger, L; Smith, E; Tomlin, B E; Walters, W; Wöhr, A

    2009-01-01

    The impact of nuclear physics on astrophysical r-process models is discussed, emphasizing the importance of beta-decay properties of neutron-rich nuclei. Several r-process motivated beta-decay experiments performed at the National Superconducting Cyclotron Laboratory are presented. The experiments include the measurement of beta-decay half-lives and neutron emission probabilities of nuclei in regions around Ni-78; Se-90; Zr-106 and Rh-120, as well as spectroscopic studies of Pd-120. A summary on the different experimental techniques employed, data analysis, results and impact on model calculations is presented.

  19. Relativistic analysis of proton elastic scattering

    Science.gov (United States)

    El Nohy, N. A.; El-Hammamy, M. N.; Yoseph, S. I.; Abdel-Moneim, A. M.

    2015-04-01

    The Dirac equation as the relevant wave equation, is used in modified DWUCK4 program to calculate the elastic scattering cross section throughout the energy range suitable for relativistic treatment of proton elastic scattering by nuclei 40Ca, 58Ni, 90Zr and 208Pb. A good fit to the experimental data is presented. The real and imaginary potentials are well determined and behave regularly with energy. The behaviour of the real central effective potential shows the development of a "wine-bottle" shape in the transition energy region and the persistence of a small attractive potential in the nuclear surface region, even at 800 MeV.

  20. Dielectric behaviour of Pb-substituted BZT ceramics

    Indian Academy of Sciences (India)

    Parveen Kumar; Sangeeta Singh; J K Juneja; K K Raina; Chandra Prakash

    2011-12-01

    Material series with compositional formula Ba1.0–PbTi0.90Zr0.10O3 (0 ≤ ≤ 0.20, in steps of 0.05) were prepared by conventional solid state method. All the samples were subjected to X-ray diffraction (XRD) studies and found to be single phase with perovskite structure. SEM measurements were done in order to collect micro-structural information. Different transition temperatures were found to depend on the Pb content. Tetragonality (/) and Curie temperature (c) increase with increase in lead content . Dielectric properties were studied as a function of temperature and frequencies.

  1. Are $\\eta$- and $\\omega$-nuclear states bound ?

    CERN Document Server

    Tsushima, K; Thomas, A W; Saitô, K

    1998-01-01

    We investigate theoretically whether it is feasible to detect $\\eta$- and $^{40}$Ca, $^{90}$Zr and $^{208}$Pb, we also investigate $^6$He, $^{11}$B and $^{26}$Mg, which are the final nuclei in the proposed experiment involving the (d,$^3$He) reaction at GSI. Potentials for the $\\eta$ and $\\omega$ mesons in these nuclei are calculated in local density approximation, embedding the mesons in the nucleus described by solving the mean-field equations of motion in the QMC model. Our results suggest that one should expect to find $\\eta$- and $\\omega$-nucleus bound states in all these nuclei.

  2. Crystallization of amorphous Co-Nb-Zr sputtered films

    Energy Technology Data Exchange (ETDEWEB)

    Battezzati, L.; Baricco, M.; Attina, P.

    1986-08-01

    Thermal analysis results obtained with some sputtered Co-Nb-Zr alloys are presented. Microstructural determinations at some stages of the crystallization process were made with transmission electron microscopy and the results given. Crystallization occurs over a wider temperature range than for binary Co/sub 90/Zr/sub 10/ ribbons. Binary Co-Nb films crystallize in the range 750-800K, some 10 degrees below ternary films. The presence of zirconium enhances the stability of the amorphous phase. An explanation of the results is given.

  3. Spin decomposition of the responses of Ca-44 and Ca-48 to 300 MeV protons

    Energy Technology Data Exchange (ETDEWEB)

    F. T. Baker; L. Bimbot; R. W. Fergerson; C. Glashausser; A. Green; O. Hausser; K. Hicks; K. Jones; C. A. Miller; M. Vetterli; R. Abegg; D. Beatty; B. Bonin; B. Castel; X. Y. Chen; V. Cupps; C. Djalali; R. Henderson; K. P. Jackson; R. Jeppesen; K. Nakayama; S. K. Nanda; R. Sawafta; S. Yen

    1991-07-01

    Angular distributions of the double-differential cross section d2σ/dΩ dE(σ) and the spin-flip probability Snn have been measured for inclusive proton inelastic scattering from 44Ca at 290 MeV and from 48Ca at 318 MeV. Excitation energies up to about 50 MeV for 44Ca and 40 MeV for 48Ca have been investigated over the laboratory angular ranges of 3° to 12° for 44Ca and 3° to 9° for 48Ca. Multipole decompositions of angular distributions of both the spin-flip cross section σSnn and the estimated cross section for ΔS=0 transitions have been performed. Distributions of strengths were deduced for ΔL=1, ΔS=0 (the giant dipole), ΔL=2, ΔS=0 (the giant quadrupole), ΔL=0, ΔS=1 (the magnetic dipole), ΔL=1, ΔS=1 (the spin dipole), and ΔL=2, ΔS=1 (the spin quadrupole). The ΔS=0 summed strengths for 44Ca are lower than for 40Ca and 48Ca. The spin-dipole summed strengths are found to be approximately independent of A. For 48Ca, essentially all M1 strength observed was in the 10.23 MeV 1+ state; for 44Ca, M1 strength was observed to be fragmented over a range of 7 to 18 Mev.

  4. Influences of calcium availability and tree species on Ca isotope fractionation in soil and vegetation

    Science.gov (United States)

    Page, B.D.; Bullen, T.D.; Mitchell, M.J.

    2008-01-01

    The calcium (Ca) isotope system is potentially of great use for understanding biogeochemical processes at multiple scales in forest ecosystems, yet remains largely unexplored for this purpose. In order to further our understanding of Ca behavior in forests, we examined two nearly adjacent hardwood-dominated catchments with differing soil Ca concentrations, developed from crystalline bedrock, to determine the variability of 44Ca/ 40Ca ratios (expressed as ??44Ca) within soil and vegetation pools. For both sugar maple and American beech, the Ca isotope compositions of the measured roots and calculated bulk trees were considerably lighter than those of soil pools at these sites, suggesting that the trees were able to preferentially take up light Ca at the root-soil interface. The Ca isotope compositions of three of four root samples were among the lightest values yet reported for terrestrial materials (??44Ca ???-3.95???). Our results further indicate that Ca isotopes were fractionated along the transpiration streams of both tree species with roots having the least ??44Ca values and leaf litter the greatest. An approximately 2??? difference in ??44Ca values between roots and leaf litter of both tree species suggests a persistent fractionation mechanism along the transpiration stream, likely related to Ca binding in wood tissue coupled with internal ion exchange. Finally, our data indicate that differing tree species demand for Ca and soil Ca concentrations together may influence Ca isotope distribution within the trees. Inter-catchment differences in Ca isotope distributions in soils and trees were minor, indicating that the results of our study may have broad transferability to studies of forest ecosystems in catchments developed on crystalline substrates elsewhere. ?? 2008 Springer Science+Business Media B.V.

  5. p-process nucleosynthesis via proton-capture reactions in thermonuclear supernovae explosions

    Directory of Open Access Journals (Sweden)

    Endres Anne

    2015-01-01

    Full Text Available Model calculations within the framework of the so-called γ process show an underproduction of the p nucleus with the highest isotopic abundace 92Mo. This discrepancy can be narrowed by taking into account the alternative production site of a type Ia supernova explosion. Here, the nucleus 92Mo can be produced by a sequence of proton-capture reactions. The amount of 92Mo nuclei produced via this reaction chain is most sensitive to the reactions 90Zr(p,γ and 91Nb(p,γ. Both rates have to be investigated experimentally to study the impact of this nucleosynthesis aspect on the long-standing 92Mo-problem. We have already measured the proton-capture reaction on 90Zr using high-resolution in-beam γ-ray spectroscopy. In this contribution, we will present our preliminary results of the total cross sections as well as the partial cross sections. Furthermore, we plan to measure the 91Nb(p,γ reaction soon. Due to the radioactive target material, the 91Nb nuclei have to be produced prior to the experiment. The current status of this production will be presented in this contribution.

  6. Nuclear two-photon decay in 0/sup +/ -> 0/sup +/ transitions

    Energy Technology Data Exchange (ETDEWEB)

    Kramp, J.; Habs, D.; Kroth, R.; Music, M.; Schirmer, J.; Schwalm, D.; Broude, C.

    1987-11-23

    The two-photon decay of the first excited 0/sup +/ state of /sup 16/O has been measured using the Heidelberg-Darmstadt crystal ball. A branching ratio of GAMMA/sub ..gamma gamma..//GAMMA/sub tot/ = (6.6+-0.5).10/sup -4/ was obtained. As in the cases of /sup 40/Ca and /sup 90/Zr previously reported by us, the 2..gamma.. decay of /sup 16/O proceeds via double E1 and M1 transitions of similar strength; the evidence is the observed interference term in the 2..gamma.. angular correlation. The ratio of the matrix elements ..cap alpha../sub E1//chi for /sup 16/O was restricted to the two inverse values (-6.2+-1.5) or (-0.16+-0.04). An interpretation of 2..gamma.. matrix elements observed for /sup 16/O, /sup 40/Ca and /sup 90/Zr in terms of the electric polarizabilities and magnetic susceptibility is given leading to a qualitative understanding of this decay mode.

  7. CPD

    African Journals Online (AJOL)

    (e.g. isocyanate may block beta-2 adrenergic ... Isocyanates (e.g. toluene diisocyanate, diphenylmethane, ... Dyes (e. g. anthraquinone, caimine, paraphenyl diamine, henna .... 2,4 mg salbutamol sulphate equivalem to 2 mg salblmtampl.

  8. Mg isotope ratios in giant stars of the globular clusters M 13 and M 71

    CERN Document Server

    Yong, D; Lambert, D L; Yong, David; Aoki, Wako; Lambert, David L.

    2006-01-01

    We present Mg isotope ratios in 4 red giants of the globular cluster M 13 and 1 red giant of the globular cluster M 71 based on spectra obtained with HDS on the Subaru Telescope. We confirm earlier results by Shetrone that for M 13, the ratio varies from (25+26)Mg/24Mg = 1 in stars with the highest Al abundance to (25+26)Mg/24Mg = 0.2 in stars with the lowest Al abundance. However, we separate the contributions of all three isotopes and find a spread in the ratio 24Mg:25Mg:26Mg with values ranging from 48:13:39 to 78:11:11. As in NGC 6752, we find a positive correlation between 26Mg and Al, an anticorrelation between 24Mg and Al, and no correlation between 25Mg and Al. In M 71, our one star has a ratio 70:13:17. For both clusters, the lowest ratios of 25Mg/24Mg and 26Mg/24Mg exceed those observed in field stars at the same metallicity, a result also found in NGC 6752. The contribution of 25Mg to the total Mg abundance is constant within a given cluster and between clusters with 25Mg/(24+25+26)Mg = 0.13. For M...

  9. Radiation resistance and parameters of activation of aluminium-magnesium-scandium and aluminium-magnesium-vanadium alloys under neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, L.I.; Ivanov, V.V.; Lazorenko, V.M.; Platov, Yu.M.; Tovtin, V.I.; Toropova, L.S. (A.A. Baikov Inst. of Metallurgy, Academy of Sciences, Moscow (Russia))

    1992-09-01

    Alloys Al-2.24Mg-0.223Sc-0.04Zr, Al-2.24Mg-0.12Sc-0.04Zr, and Al-2.24Mg-0.05V (at.%) annealed at 150deg C and 400deg C were irradiated at [approx equal] 70 and [approx equal] 150deg C in the SM-2 reactor. The maximum neutron fluence was 4.7x10[sup 24] m[sup -2] (E > 0.1 MeV). The tensile tests were carried out in the temperature range 20 to 350deg C. Alloy Al-2.24 Mg-0.23Sc-0.04Zr annealed at 400deg C and alloy Al-2.24Mg-0.12Sc-0.04Zr annealed at 150deg C at all test temperatures retained good mechanical properties after irradiation. The mechanisms for the radiation resistance of aluminium-scandium and aluminium-magnesium-scandium alloys are discussed. Calculations of induced radioactivity and its decay behaviour after shutdown in aluminium and Al-2.24Mg-(0.12-0.23)Sc alloys were carried out. Composition of the radionuclides in these materials after irradiation in the SM-2 reactor were also determined using a gamma-spectroscopy technique. (orig.).

  10. Environmental geochemistry of calcium isotopes: Applications of a new stable isotope approach

    Institute of Scientific and Technical Information of China (English)

    LIU Zhanmin; LIU Congqiang; HAN Guilin; WANG Zhongliang; XUE Zichen; SONG Zhaoliang; YANG Cheng

    2006-01-01

    This paper summarizes isotope fractionation mechanism, analytical method and applications in environmental geochemistry of calcium isotopes. Calcium isotopic composition can be used to constrain material sources and study geological and environmental processes as the isotopic composition of calcium (δ 44Ca) and fractionation processes depend on geochemical circumstances in nature. Recently, thanks to current advances in analytical technology of calcium isotopes, calcium isotopes are broadly used in biological and geochemical studies, such as the mechanism of plants imbibing nutrients through their roots, calcium transport in the environmental ecosystem, calcium cycle in oceans and paleo-oceans and paleo-climate. The elementary data show that δ44Ca values vary from -2.88‰ to 0.92‰ in natural samples.

  11. Measurement of (43)Sc and (44)Sc production cross-section with an 18MeV medical PET cyclotron.

    Science.gov (United States)

    Carzaniga, Tommaso Stefano; Auger, Martin; Braccini, Saverio; Bunka, Maruta; Ereditato, Antonio; Nesteruk, Konrad Pawel; Scampoli, Paola; Türler, Andreas; van der Meulen, Nicholas

    2017-11-01

    (43)Sc and (44)Sc are positron emitter radionuclides that, in conjunction with the β(-) emitter (47)Sc, represent one of the most promising possibilities for theranostics in nuclear medicine. Their availability in suitable quantity and quality for medical applications is an open issue and their production with medical cyclotrons represents a scientific and technological challenge. For this purpose, an accurate knowledge of the production cross sections is mandatory. In this paper, we report on the cross section measurement of the reactions (43)Ca(p,n)(43)Sc, (44)Ca(p,2n) (43)Sc, (46)Ti(p,α)(43)Sc, and (44)Ca(p,n)(44)Sc at the Bern University Hospital cyclotron. A study of the production yield and purity performed by using commercially available enriched target materials is also presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Observation of single Ca{sup +} ions for trace isotope analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Y. [Department of Quantum Engineering and Systems Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)], E-mail: yhashi@lyman.q.t.u-tokyo.ac.jp; Matsuoka, L.; Nagamoto, D. [Department of Quantum Engineering and Systems Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Hasegawa, S. [Department of Quantum Engineering and Systems Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)], E-mail: hasegawa@q.t.u-tokyo.ac.jp

    2008-06-15

    We developed an ion trap - laser cooling system for observing the laser induced fluorescence (LIF) of a single ion, in the view of utilizing it for the trace isotope analysis of Ca. We observed stepwise LIF signals, which correspond to the numbers of trapped {sup 40}Ca{sup +} ions ({sup 40}Ca/Ca = 96.9%). The detection efficiency was evaluated and the observation of single ions demonstrated the experimental feasibility of trace isotope analysis. Furthermore, as the next step towards trace isotope analysis, we report observation of the even calcium isotopes, {sup 44}Ca ({sup 44}Ca/Ca = 2.09%) and {sup 48}Ca ({sup 48}Ca/Ca = 0.187%), without the use of a selective loading method.

  13. Thermal-neutron capture gamma rays from natural calcium

    NARCIS (Netherlands)

    Gruppelaar, H.; Spilling, P.

    1967-01-01

    Gamma rays from thermal-neutron capture in natural Ca and enriched 40Ca were investigated with a 5 cm3 Ge(Li) detector. Many low-energy γ-lines have been found. More than 90% of the γ-rays result from capture in 40Ca and about 5% from capture in 44Ca. From the data a decay scheme of 41Ca and a parti

  14. Application of multiple scattering theory to lower-energy elastic nucleon-nucleus scattering

    Energy Technology Data Exchange (ETDEWEB)

    Chinn, C.R.; Elster, C.; Thaler, R.M.; Weppner, S.P. (Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States) Center for Computationally Intensive Physics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States) Institute of Nuclear Particle Physics, and Department of Physics, Ohio University, Athens, Ohio 45701 (United States) Physics Department, Case Western Reserve University, Cleveland, Ohio 44106 (United States))

    1995-03-01

    The optical model potentials for nucleon-nucleus elastic scattering at 65 meV are calculated for [sup 12]C, [sup 16]O, [sup 28]Si, [sup 40]Ca, [sup 56]Fe, [sup 90]Zr, and [sup 208]Pb in first-order multiple scattering theory, following the prescription of the spectator expansion, where the only inputs are the free nucleon-nucleon (NN) potentials, the nuclear densities, and the nuclear mean field as derived from microscopic nuclear structure calculations. These potentials are used to predict differential cross sections, analyzing powers, and spin rotation functions for neutron and proton scattering at 65 MeV projectile energy and compared with available experimental data. The theoretical curves are in very good agreement with the data. The modification of the propagator due to the coupling of the struck nucleon to the residual nucleus is seen to be significant at this energy and invariably improves the congruence of theoretical prediction and measurement.

  15. Application of multiple scattering theory to lower-energy elastic nucleon-nucleus scattering

    Science.gov (United States)

    Chinn, C. R.; Elster, Ch.; Thaler, R. M.; Weppner, S. P.

    1995-03-01

    The optical model potentials for nucleon-nucleus elastic scattering at 65 meV are calculated for 12C, 16O, 28Si, 40Ca, 56Fe, 90Zr, and 208Pb in first-order multiple scattering theory, following the prescription of the spectator expansion, where the only inputs are the free nucleon-nucleon (NN) potentials, the nuclear densities, and the nuclear mean field as derived from microscopic nuclear structure calculations. These potentials are used to predict differential cross sections, analyzing powers, and spin rotation functions for neutron and proton scattering at 65 MeV projectile energy and compared with available experimental data. The theoretical curves are in very good agreement with the data. The modification of the propagator due to the coupling of the struck nucleon to the residual nucleus is seen to be significant at this energy and invariably improves the congruence of theoretical prediction and measurement.

  16. Excitation of 0/sup -/ states in reactions of proton inelastic scattering at intermediate energies

    Energy Technology Data Exchange (ETDEWEB)

    Vdovin, A.I.; Gareev, F.A.; Ershov, S.N.; Mora, M.; Ponomarev, V.Y.

    1986-08-01

    In the distorted-wave impulse approximation we calculate the excitation of one-phonon states with L/sup ..pi../ = 0/sup -/ of the /sup 90/Zr nucleus in inelastic proton scattering at E/sub p/ = 200 MeV. The central and tensor interactions of the incident proton and the nucleons of the nucleus are taken into account and it is shown that the tensor interaction plays an important role. The effects of exchange knockout are taken into account by means of a nonlocal form factor. The structure and transition densities of 0/sup -/ states are calculated with a separable spin-dipole interaction. The possibility of observation of the isovector 0/sup -/ resonance in ( p,p') scattering is discussed.

  17. Improvements on Semi-Classical Distorted-Wave model

    Energy Technology Data Exchange (ETDEWEB)

    Sun Weili; Watanabe, Y.; Kuwata, R. [Kyushu Univ., Fukuoka (Japan); Kohno, M.; Ogata, K.; Kawai, M.

    1998-03-01

    A method of improving the Semi-Classical Distorted Wave (SCDW) model in terms of the Wigner transform of the one-body density matrix is presented. Finite size effect of atomic nuclei can be taken into account by using the single particle wave functions for harmonic oscillator or Wood-Saxon potential, instead of those based on the local Fermi-gas model which were incorporated into previous SCDW model. We carried out a preliminary SCDW calculation of 160 MeV (p,p`x) reaction on {sup 90}Zr with the Wigner transform of harmonic oscillator wave functions. It is shown that the present calculation of angular distributions increase remarkably at backward angles than the previous ones and the agreement with the experimental data is improved. (author)

  18. Neutron capture on (94)Zr: Resonance parameters and Maxwellian-averaged cross sections

    CERN Document Server

    Tagliente, G; Fujii, K; Abbondanno, U; Aerts, G; Alvarez, H; Alvarez-Velarde, F; Andriamonje, S; Andrzejewski, J; Audouin, L; Badurek, G; Baumann, P; Becvar, F; Belloni, F; Berthoumieux, E; Bisterzo, S; Calvino, F; Calviani, M; Cano-Ott, D; Capote, R; Carrapico, C; Cennini, P; Chepel, V; Chiaveri, E; Colonna, N; Cortes, G; Couture, A; Cox, J; Dahlfors, M; David, S; Dillmann, I; Domingo-Pardo, C; Dridi, W; Duran, I; Eleftheriadis, C; Embid-Segura, M; Ferrari, A; Ferreira-Marques, R; Furman, W; Gallino, R; Goncalves, I; Gonzalez-Romero, E; Gramegna, F; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martinez, A; Jericha, E; Kappeler, F; Kadi, Y; Karadimos, D; Karamanis, D; Kerveno, M; Kossionides, E; Krticka, M; Lamboudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marrone, S; Martinez, T; Massimi, C; Mastinu, P; Mengoni, A; Moreau, C; Mosconi, M; Neves, F; Oberhummer, H; O'Brien, S; Pancin, J; Papachristodoulou, C; Papadopoulos, C; Paradela, C; Patronis, N; Pavlik, A; Pavlopoulos, P; Perrot, L; Pigni, M.T; Plag, R; Plompen, A; Plukis, A; Poch, A; Praena, J; Pretel, C; Quesada, J; Rauscher, T; Reifarth, R; Rosetti, M; Rubbia, C; Rudolf, G; Rullhusen, P; Salgado, J; Santos, C; Sarchiapone, L; Savvidis, I; Stephan, C; Tain, J.L; Tassan-Got, L; Tavora, L; Terlizzi, R; Vannini, G; Vaz, P; Ventura, A; Villamarin, D; Vincente, M.C; Vlachoudis, V; Vlastou, R; Voss, F; Walter, S; Wiescher, M; Wisshak, K

    2011-01-01

    The neutron capture cross sections of the Zr isotopes play an important role in nucleosynthesis studies. The s-process reaction flow between the Fe seed and the heavier isotopes passes through the neutron magic nucleus (90)Zr and through (91,92,93,94)Zr, but only part of the flow extends to (96)Zr because of the branching point at (95)Zr. Apart from their effect on the s-process flow, the comparably small isotopic (n, gamma) cross sections make Zr also an interesting structural material for nuclear reactors. The (94)Zr (n, gamma) cross section has been measured with high resolution at the spallation neutron source n_TOF at CERN and resonance parameters are reported up to 60 keV neutron energy.

  19. On the extraction of weak transition strengths via the (3He,t) reaction at 420 MeV

    CERN Document Server

    Zegers, R G T; Akimune, H; Austin, Sam M; Berg, A M van den; Brown, B A; Fujita, Y; Fujiwara, M; Galès, S; Guess, C J; Harakeh, M N; Hashimoto, H; Hatanaka, K; Hayami, R; Hitt, G W; Howard, M E; Itoh, M; Kawabata, T; Kawase, K; Kinoshita, M; Matsubara, M; Nakanishi, K; Nakayama, S; Okumura, S; Ohta, T; Sakemi, Y; Shimbara, Y; Shimizu, Y; Scholl, C; Simenel, C; Tameshige, Y; Tamii, A; Uchida, M; Yamagata, T; Yosoi, M

    2007-01-01

    Differential cross sections for transitions of known weak strength were measured with the (3He,t) reaction at 420 MeV on targets of 12C, 13C, 18O, 26Mg, 58Ni, 60Ni, 90Zr, 118Sn, 120Sn and 208Pb. Using this data, it is shown the proportionalities between strengths and cross sections for this probe follow simple trends as a function of mass number. These trends can be used to confidently determine Gamow-Teller strength distributions in nuclei for which the proportionality cannot be calibrated via beta-decay strengths. Although theoretical calculations in distorted-wave Born approximation overestimate the data, they allow one to understand the main experimental features and to predict deviations from the simple trends observed in some of the transitions.

  20. New type of asymmetric fission in proton-rich nuclei

    CERN Document Server

    Andreyev, A N; Huyse, M; Van Duppen, P; Antalic, S; Barzakh, A; Bree, N; Cocolios, T E; Comas, V F; Diriken, J; Fedorov, D; Fedosseev, V; Franchoo, S; Heredia, J A; Ivanov, O; Koster, U; Marsh, B A; Nishio, K; Page, R D; Patronis, N; Seliverstov, M; Tsekhanovich, I; Van den Bergh, P; Van De Walle, J; Venhart, M; Vermote, S; Veselsky, M; Wagemans, C; Ichikawa, T; Iwamoto, A; Moller, P; Sierk, A J

    2010-01-01

    A very exotic process of ${\\beta}$-delayed fission of $^{180}$Tl is studied in detail by using resonant laser ionization with subsequent mass separation at ISOLDE (CERN). In contrast to common expectations, the fission-fragment mass distribution of the post-${\\beta}$-decay daughter nucleus $^{180}$Hg (N/Z=1.25) is asymmetric. This asymmetry is more surprising since a mass-symmetric split of this extremely neutron-deficient nucleus would lead to two $^{90}$Zr fragments, with magic N=50 and semimagic Z=40. This is a new type of asymmetric fission, not caused by large shell effects related to fragment magic proton and neutron numbers, as observed in the actinide region. The newly measured branching ratio for $\\beta$-delayed fission of $^{180}$Tl is 3.6(7)×10$^{-3}$%, approximately 2 orders of magnitude larger than in an earlier study.

  1. The gamma-ray spectrometer HORUS and its applications for nuclear astrophysics

    CERN Document Server

    Netterdon, L; Endres, J; Fransen, C; Hennig, A; Mayer, J; Müller-Gatermann, C; Sauerwein, A; Scholz, P; Spieker, M; Zilges, A

    2014-01-01

    A dedicated setup for the in-beam measurement of absolute cross sections of astrophysically relevant charged-particle induced reactions is presented. These, usually very low, cross sections at energies of astrophysical interest are important to improve the modeling of the nucleosynthesis processes of heavy nuclei. Particular emphasis is put on the production of the $p$ nuclei during the astrophysical $\\gamma$ process. The recently developed setup utilizes the high-efficiency $\\gamma$-ray spectrometer HORUS, which is located at the 10 MV FN tandem ion accelerator of the Institute for Nuclear Physics in Cologne. The design of this setup will be presented and results of the recently measured $^{89}$Y(p,$\\gamma$)$^{90}$Zr reaction will be discussed. The excellent agreement with existing data shows, that the HORUS spectrometer is a powerful tool to determine total and partial cross sections using the in-beam method with high-purity germanium detectors.

  2. Multinucleon transfer reactions in closed-shell nuclei

    CERN Document Server

    Szilner, S; Corradi, L; Marginean, N; Pollarolo, G; Stefanini, A M; Beghini, S; Behera, B R; Fioretto, E; Gadea, A; Guiot, B; Latina, A; Mason, P; Montagnoli, G; Scarlassara, F; Trotta, M; de Angelis, G; Della Vedova, F; Farnea, E; Haas, F; Lenzi, S; Lunardi, S; Marginean, R; Menegazzo, R; Napoli, D R; Nespolo, M; Pokrovsky, I V; Recchia, F; Romoli, M; Salsac, M -D; Soic, N; Valiente-Dobon, J J

    2007-01-01

    Multinucleon transfer reactions in 40Ca+96Zr and 90Zr+208Pb have been measured at energies close to the Coulomb barrier in a high resolution gamma-particle coincidence experiment. The large solid angle magnetic spectrometer PRISMA coupled to the CLARA gamma-array has been employed. Trajectory reconstruction has been applied for the complete identification of transfer products. Mass and charge yields, total kinetic energy losses, gamma transitions of the binary reaction partners, and comparison of data with semiclassical calculations are reported. Specific transitions in 95Zr populated in one particle transfer channels are discussed in terms of particle-phonon couplings. The gamma decays from states in 42Ca in the excitation energy region expected from pairing vibrations are also observed.

  3. Role of momentum transfer in the quenching of the Gamow-Teller strength

    Energy Technology Data Exchange (ETDEWEB)

    Marketin, T.; Martinez-Pinedo, G.; Paar, N.; Vretenar, D. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt, Germany and Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia)

    2012-10-20

    A recent analysis of (p,n) and (n,p) reaction data from {sup 90}Zr was performed recently, where a significant amount of Gamow-Teller strength was found above the resonance, an energy region previously unreachable by experimental setups. The extracted strengths in the {beta}{sub -} and the {beta}{sub +} channel indicate that approximately 10% of the total strength necessary to satisfy the model independent Ikeda sum rule is missing. One possible source of this discrepancy is the treatment of the isovector spin monopole (IVSM) mode of excitation which has been found to occurr at high excitation energies. Employing the relativistic Hartree-Bogoliubov (RHB) model and the protonneutron relativistic quasiparticle random phase approximation (pn-RQRPA) to calculate the nuclear response, we explore the contribution of the IVSM mode to the total L= 0 strength and apply our results to the available data.

  4. Towards a Microscopic Reaction Description Based on Energy Density Functionals

    CERN Document Server

    Nobre, G P A; Escher, J E; Thompson, I J; Dupuis, M; Terasaki, J; Engel, J

    2011-01-01

    A microscopic calculation of reaction cross sections for nucleon-nucleus scattering has been performed by explicitly coupling the elastic channel to all particle-hole excitations in the target and one-nucleon pickup channels. The particle-hole states may be regarded as doorway states through which the flux flows to more complicated configurations, and subsequently to long-lived compound nucleus resonances. Target excitations for $^{40,48}$Ca, $^{58}$Ni, $^{90}$Zr and $^{144}$Sm were described in a random-phase framework using a Skyrme functional. Reaction cross sections obtained agree very well with experimental data and predictions of a state-of-the-art fitted optical potential. Couplings between inelastic states were found to be negligible, while the pickup channels contribute significantly. The effect of resonances from higher-order channels was assessed. Elastic angular distributions were also calculated within the same method, achieving good agreement with experimental data. For the first time observed a...

  5. The Giant Dipole Resonance built on highly excited states — results of the MEDEA experiment

    Science.gov (United States)

    Suomijärvi, T.; Le Faou, J. H.; Blumenfeld, Y.; Piattelli, P.; Agodi, C.; Alamanos, N.; Alba, R.; Auger, F.; Bellia, G.; Chomaz, Ph.; Coniglione, R.; Del Zoppo, A.; Finocchiaro, P.; Frascaria, N.; Gaardhøje, J. J.; Garron, J. P.; Gillibert, A.; Lamehi-Rachti, M.; Liguori-Neto, R.; Maiolino, C.; Migneco, E.; Russo, G.; Roynette, J. C.; Santonocito, D.; Sapienza, P.; Scarpaci, J. A.; Smerzi, A.

    1994-03-01

    Gamma-rays, light charged particles and evaporation residues emitted from hot nuclei formed in the 36Ar + 90Zr reaction at 27 MeV/u have been measured with a nearly 4π barium fluoride multidetector. It is shown that hot Sn-like nuclei with a range of excitation energies between 300 and 600 MeV are produced. The γ-ray yield from the decay of the Giant Dipole Resonance in these nuclei is shown to remain constant over this excitation energy range. The measured γ-ray spectra are compared with statistical calculations encompassing several recent theoretical models for the quenching of gamma-ray emission from the dipole resonance at very high temperatures.

  6. Progress of Covariance Evaluation at the China Nuclear Data Center

    Energy Technology Data Exchange (ETDEWEB)

    Xu, R., E-mail: xuruirui@ciae.ac.cn [China Nuclear Data Center, P.O. Box, 275(41), Beijing 102413 (China); Zhang, Q. [China Nuclear Data Center, P.O. Box, 275(41), Beijing 102413 (China); Shanxi Normal University, Linfen, Shanxi Province 041004 (China); Zhang, Y.; Liu, T.; Ge, Z.; Lu, H.; Sun, Z.; Yu, B. [China Nuclear Data Center, P.O. Box, 275(41), Beijing 102413 (China); Tang, G. [Peking University, Beijing 100871 (China)

    2015-01-15

    Covariance evaluations at the China Nuclear Data Center focus on the cross sections of structural materials and actinides in the fast neutron energy range. In addition to the well-known Least-squares approach, a method based on the analysis of the sources of experimental uncertainties is especially introduced to generate a covariance matrix for a particular reaction for which multiple measurements are available. The scheme of the covariance evaluation flow is presented, and an example of n+{sup 90}Zr is given to illuminate the whole procedure. It is proven that the accuracy of measurements can be properly incorporated into the covariance and the long-standing small uncertainty problem can be avoided.

  7. Symmetry energy effects on isovector properties of neutron rich nuclei with a density functional approach

    CERN Document Server

    Papazoglou, M C

    2014-01-01

    We employ a variational method to study the effect of the symmetry energy on the neutron skin thickness and the symmetry energy coefficients of various neutron rich nuclei. We concentrate our interest on $^{208}$Pb, $^{124}$Sn, $^{90}$Zr, and $^{48}$Ca, although the method can be applied in the totality of medium and heavy neutron rich nuclei. Our approach has the advantage that the isospin asymmetry function $\\alpha(r)$, which is the key quantity to calculate isovector properties of various nuclei, is directly related with the symmetry energy as a consequence of the variational principle. Moreover, the Coulomb interaction is included in a self-consistent way and its effects can be separated easily from the nucleon-nucleon interaction. We confirm, both qualitatively and quantitatively, the strong dependence of the symmetry energy on the various isovector properties for the relevant nuclei, using possible constraints between the slope and the value of the symmetry energy at the saturation density.

  8. Disentangling the Transfer Couplings on Near-barrier Fusion

    Institute of Scientific and Technical Information of China (English)

    B.R.Behera; L.Corradi; E.Fioretto; A.Gadea; A.Latina; A.M.Stefanini; S.Szilner; M.Trotta; Y.W.Wu; S.Beghini; G.Montagnoli; F.Scarlassara; R.Silvestri; N.Rowley

    2002-01-01

    Fusion-evaporation cross sections have been measured in the reaction 48Ca+90,96Zr from well belowto well above the Coulomb barrier,using the 48Ca beams of the XTU Tandem accelerator of LNL. The48Ca beam was produced by a sputter ion source, where CaH samples were used. The beam energy wasdefined with an uncertainty less than ≈1/800 and the beam current was in the range 5~10 pnA. Thetargets were evaporations of 90Zr and 96ZrO2(50μg/cm2) on carbon backings (15μg/cm2). For each

  9. A consistent analysis of (p,p`) and (n,n`) reactions using the Feshbach-Kerman-Koonin model

    Energy Technology Data Exchange (ETDEWEB)

    Yoshioka, S.; Watanabe, Y.; Harada, M. [Kyushu Univ., Fukuoka (Japan)] [and others

    1997-03-01

    Double-differential proton emission cross sections were measured for proton-induced reactions on several medium-heavy nuclei ({sup 54,56}Fe, {sup 60}Ni, {sup 90}Zr, and {sup 93}Nb) at two incident energies of 14.1 and 26 MeV. The (p,p`) data for {sup 56}Fe and {sup 93}Nb were compared with available data of (n,n`) scattering for the same target nuclei and incident energies, and both data were analyzed using the Feshbach-Kerman-Koonin model to extract the strength V{sub 0} of the effective N-N interaction which is the only free parameter used in multistep direct calculations. (author)

  10. Shape coexistence at the proton drip-line: First identification of excited states in 180Pb

    CERN Document Server

    Rahkila, P; Pakarinen, J; Gray-Jones, C; Greenlees, P T; Jakobsson, U; Jones, P; Julin, R; Juutinen, S; Ketelhut, S; Koivisto, H; Leino, M; Nieminen, P; Nyman, M; Papadakis, P; Paschalis, S; Petri, M; Peura, P; Roberts, O J; Ropponen, T; Ruotsalainen, P; Saren, J; Scholey, C; Sorri, J; Tuff, A G; Uusitalo, J; Wadsworth, R; Bender, M; Heenen, P -H

    2010-01-01

    Excited states in the extremely neutron-deficient nucleus, 180Pb, have been identified for the first time using the JUROGAM II array in conjunction with the RITU recoil separator at the Accelerator Laboratory of the University of Jyvaskyla. This study lies at the limit of what is presently achievable with in-beam spectroscopy, with an estimated cross-section of only 10 nb for the 92Mo(90Zr,2n)180Pb reaction. A continuation of the trend observed in 182Pb and 184Pb is seen, where the prolate minimum continues to rise beyond the N=104 mid-shell with respect to the spherical ground state. Beyond mean-field calculations are in reasonable correspondence with the trends deduced from experiment.

  11. Development of Enhanced, Permanently-Installed, Neutron Activation Diagnostic Hardware for NIF

    Science.gov (United States)

    Edwards, E. R.; Jedlovec, D. R.; Carrera, J. A.; Yeamans, C. B.

    2016-05-01

    Neutron activation diagnostics are baseline neutron yield and flux measurement instruments at the National Ignition Facility. Up to 19 activation samples are distributed around the target chamber. Currently the samples must be removed to be counted, creating a 1-2 week data turn-around time and considerable labor costs. An improved system consisting of a commercially available LaBr3(Ce) scintillator and Power over Ethernet electronics is under development. A machined zirconium-702 cap over the detector is the activation medium to measure the 90Zr(n,2n)89Zr reaction. The detectors are located at the current neutron activation diagnostic sites and monitored remotely. Because they collect data in real time yield values are returned within a few hours after a NIF shot.

  12. Application of the Zr/Hf ratio in the determination of hafnium in geochemical samples by high-resolution inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Liu, Ya Xuan; Li, Qing Xia; Ma, Na; Sun, Xiao Ling; Bai, Jin Feng; Zhang, Qin

    2014-12-02

    Hafnium content and its change are of significance in geochemistry and cosmochemistry; however, the determination of hafnium has always been problematic in analytical chemistry. In this paper, a new idea is proposed for the determination of hafnium in geochemical samples, including rocks, soils, and stream sediments. Through the comparison of two conventional open-type acid digestion methods (HF-HNO3-HClO4 and HF-HNO3-H2SO4), it was found that although neither of these methods could fully digest the zirconium and hafnium in a sample, the zirconium and hafnium digestion behaviors in one sample were consistent in the 60 experimental geochemical reference materials with different properties, so the experimentally determined Zr/Hf ratio in solution could be used to calculate the hafnium content in a sample. In addition, possible mass spectral interferences during the determination of zirconium and hafnium by high resolution inductively coupled plasma mass spectrometry (HR-ICPMS) were studied, and it was found that the mass spectral interferences of the selected isotopes (90)Zr and (178)Hf could be neglected. The mass spectral behaviors of (90)Zr and (178)Hf were also very consistent during the determination by HR-ICPMS. Since the hafnium content was calculated using the ratio value, all of the errors (including the errors in weighing process, the accidental errors during operation and the instrument fluctuation in the determination) of the Zr/Hf ratio could be effectively reduced or even eliminated. The relative standard deviation of the actual samples was lower than 3.2%, and the detection limit of the method (considering the dilution effect and matrix effect during measurement of the Zr/Hf ratio and zirconium content) was 0.04 μg/g. The proposed method could satisfy the requirement for the determination of hafnium in geochemical samples.

  13. Technological developments for strontium-90 determination using AMS

    Energy Technology Data Exchange (ETDEWEB)

    Satou, Yukihiko, E-mail: yukihiko@ied.tsukuba.ac.jp [Accelerator Mass Spectrometry Group, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Sueki, Keisuke; Sasa, Kimikazu; Matsunaka, Tetsuya; Takahashi, Tsutomu; Shibayama, Nao; Izumi, Daiki [Accelerator Mass Spectrometry Group, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Kinoshita, Norikazu [Institute of Technology, Shimizu Corporation, 3-4-17 Etchujima, Koto-ku, Tokyo 135-8530 (Japan); Matsuzaki, Hiroyuki [The University Museum, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan)

    2015-10-15

    Accelerator mass spectrometry (AMS) is one of method used for {sup 90}Sr determination. It would enable rapid {sup 90}Sr measurements from environmental samples such as water, soil, and milk. However, routine analysis of {sup 90}Sr using AMS has not yet been achieved because of difficulties associated with isobaric separation and production of intense negative ion beams characterized by currents from hundreds of nanoamperes to several microamperes. We have developed a rapid procedure for preparing samples with optimum compositions for use with AMS, which enables production of intense Sr beam currents from an ion source. Samples of SrF{sub 2} were prepared from a standard Sr solution and agricultural soil. The time required to prepare a SrF{sub 2} sample from a soil sample was 10 h. Negative {sup 88}SrF{sub 3}{sup −} ions were successfully extracted at 500 nA from mixed samples of SrF{sub 2} and PbF{sub 2}. In the present work, negative ions of {sup 90}Zr, included as an impurity, were accelerated with a tandem accelerator operated at a terminal voltage of 5 MV. Ions characterized by a charge state of 6+ were channeled into a gas counter. An atomic ratio of {sup 90}Zr/{sup 88}Sr of 3 × 10{sup −8} was estimated for the soil sample. No signal was detected from the assay of PbF{sub 2}, which was pressed in an aluminum cathode, for a mass number of 90. PbF{sub 2} revealed good performance in the production of negative SrF{sub 3}{sup −} molecular ion beams and detection of {sup 90}Sr with a gas counter.

  14. 聚变-裂变混合堆水冷包层中子物理性能研究%Neutron Physical Characteristics of Light Water Cooled Blanket of Fusion-Fission Hybrid Reactor

    Institute of Scientific and Technical Information of China (English)

    徐红; 杨永伟; 周志伟

    2009-01-01

    研究直接应用国际热核聚变实验堆(ITER)规模的聚变堆作为中子驱动源,采用天然铀为初装核燃料,并采用现有压水堆核电厂成熟的轻水慢化和冷却技术,设计聚变-裂变混合堆裂变及产氚包层的技术可行性.应用MCNP与Origen2相耦合的程序进行计算分析,研究不同核燃料对包层有效增殖系数、氚增殖比、能量放大系数和外中子源效率等中子物理性能的影响.计算分析结果显示,现有核电厂广泛使用的UO_2核燃料以及下一代裂变堆推荐采用的UC、UN和U_(90)Zr_(10)等高性能陶瓷及合金核燃料作为水冷包层的核燃料,都能满足以产能发电为设计目标的新型聚变-裂变混合堆能量放大倍数的设计要求,但只有UC和U90Zr10燃料同时满足聚变燃料氚的生产与消耗自持的要求.研究结果对进一步研发满足未来核能可持续发展的新型聚变-裂变混合堆技术具有潜在参考价值.

  15. Technological developments for strontium-90 determination using AMS

    Science.gov (United States)

    Satou, Yukihiko; Sueki, Keisuke; Sasa, Kimikazu; Matsunaka, Tetsuya; Takahashi, Tsutomu; Shibayama, Nao; Izumi, Daiki; Kinoshita, Norikazu; Matsuzaki, Hiroyuki

    2015-10-01

    Accelerator mass spectrometry (AMS) is one of method used for 90Sr determination. It would enable rapid 90Sr measurements from environmental samples such as water, soil, and milk. However, routine analysis of 90Sr using AMS has not yet been achieved because of difficulties associated with isobaric separation and production of intense negative ion beams characterized by currents from hundreds of nanoamperes to several microamperes. We have developed a rapid procedure for preparing samples with optimum compositions for use with AMS, which enables production of intense Sr beam currents from an ion source. Samples of SrF2 were prepared from a standard Sr solution and agricultural soil. The time required to prepare a SrF2 sample from a soil sample was 10 h. Negative 88SrF3- ions were successfully extracted at 500 nA from mixed samples of SrF2 and PbF2. In the present work, negative ions of 90Zr, included as an impurity, were accelerated with a tandem accelerator operated at a terminal voltage of 5 MV. Ions characterized by a charge state of 6+ were channeled into a gas counter. An atomic ratio of 90Zr/88Sr of 3 × 10-8 was estimated for the soil sample. No signal was detected from the assay of PbF2, which was pressed in an aluminum cathode, for a mass number of 90. PbF2 revealed good performance in the production of negative SrF3- molecular ion beams and detection of 90Sr with a gas counter.

  16. Magnetoelastic study of amorphous Fe 90+ xZr 10- x alloys

    Science.gov (United States)

    Balakrishnan, K.; Babu, P. D.; Ganesan, V.; Srinivasan, R.; Kaul, S. N.

    2002-09-01

    Young's modulus ( E) of stress-relieved Fe-rich Fe-Zr amorphous alloys has been measured as a function of temperature in the range 80-350 K using the vibrating reed technique. The measured E( T) data are corrected for thermal expansion and non-magnetic background, Ebg( T), to arrive at the magnetic contribution to Young's modulus, Δ E/ EEbg=[ E( T)- Ebg( T)]/ E( T) Ebg( T), in the ferromagnetic state. A strikingly different behaviour of Δ E/ EEbg is observed in alloys whose Fe content differs barely by 1 at% in that Δ E/ EEbgdecreases monotonously in amorphous (a-) Fe 90Zr 10, whereas after an initial decrease it increases steeply in a-Fe 91Zr 9 as the temperature is lowered from the Curie point ( TC) down to 80 K. Generalisation of the Landau theory of phase transitions leads to an expression for Δ E/ EEbg that includes both first- and second-order magnetoelastic contributions, which respectively are linear and quadratic in stress. This expression is shown to provide a straightforward explanation for the distinctly different behaviour of Δ E/ EEbg observed in a-Fe 90Zr 10 and a-Fe 91Zr 9 alloys. Furthermore, the present theoretical approach not only brings out clearly the role of exchange-enhanced local spin-density fluctuations in the thermal demagnetisation of spontaneous magnetisation but also permits an accurate determination of the pressure dependence of TC from the Young's modulus measurements on systems (which exhibit strong magnetoelastic effects) such as the alloys in question.

  17. Antimuscarinic-induced convulsions in fasted animals after food intake: evaluation of the effects of levetiracetam, topiramate and different doses of atropine.

    Science.gov (United States)

    Büget, Bahar; Türkmen, Aslı Zengin; Allahverdiyev, Oruc; Enginar, Nurhan

    2016-01-01

    This study evaluated the effects of different doses of atropine and new antiepileptics, levetiracetam and topiramate, on the development of convulsions triggered by food intake in antimuscarinic-treated fasted animals. Mice deprived of food for 24 h and treated i.p. with atropine at a dose of 2.4 or 24 mg/kg developed convulsions after being allowed to eat ad libitum. No convulsions were observed in fasted animals treated with 0.24 mg/kg atropine. There was no difference in the incidence of convulsions between the two atropine treatments, but latency to convulsions was longer in 24 mg/kg atropine treated animals. The lowest dose of atropine, 0.24 mg/kg, caused stage 1 and stage 2 activity, but did not provide the convulsive endpoint (stage 3, 4, 5 activity). Administration of levetiracetam (50 or 200 mg/kg) or topiramate (50 or 100 mg/kg) to another group of 24-h fasted mice was ineffective in reducing the incidence of convulsions developed in the animals after 2.4 mg/kg atropine treatment and food intake. However, the higher dose of levetiracetam prolonged the onset of convulsions. Present results demonstrated the efficacy of low and high doses of atropine on the development of convulsions in fasted animals and provided additional evidence for the ineffectiveness of antiepileptic treatment in these seizures.

  18. Magnesium and 54Cr isotope compositions of carbonaceous chondrite chondrules – Insights into early disk processes

    DEFF Research Database (Denmark)

    Olsen, Mia Bjørg Stolberg; Wielandt, Daniel Kim Peel; Schiller, Martin

    2016-01-01

    .04–0.27) and display little or no evidence for secondary alteration processes. The CV and CR chondrules show variable 25Mg/24Mg and 26Mg/24Mg values corresponding to a range of mass-dependent fractionation of ∼500 ppm (parts per million) per atomic mass unit. This mass-dependent Mg isotope fractionation is interpreted......We report on the petrology, magnesium isotopes and mass-independent 54Cr/52Cr compositions (μ54Cr) of 42 chondrules from CV (Vigarano and NWA 3118) and CR (NWA 6043, NWA 801 and LAP 02342) chondrites. All sampled chondrules are classified as type IA or type IAB, have low 27Al/24Mg ratios (0...

  19. Magneto-optical trap formed by elliptically polarised light waves for Mg atoms

    Science.gov (United States)

    Prudnikov, O. N.; Brazhnikov, D. V.; Taichenachev, A. V.; Yudin, V. I.; Goncharov, A. N.

    2016-07-01

    We consider a magneto-optical trap (MOT) formed by elliptically polarised waves for 24Mg atoms on a closed optical 3P2 → 3D3 (λ = 383.8 nm) transition in the ɛ - θ - ɛ¯ configuration of the field. Compared with a known MOT formed by circularly polarised waves (σ+ - σ- configuration), the suggested configuration of the trap formed by fields of ɛ - θ - ɛ¯ configuration allows deeper sub-Doppler cooling of trapped 24Mg atoms, which cannot be implemented in a conventional trap formed by fields of σ+ - σ- configuration.

  20. α-clustering effects in dissipative 12C + 12C reactions at 95 MeV

    Science.gov (United States)

    Baiocco, G.; Morelli, L.; Gulminelli, F.; D'Agostino, M.; Bruno, M.; Abbondanno, U.; Barlini, S.; Bini, M.; Carboni, S.; Casini, G.; Cinausero, M.; Degerlier, M.; Gramegna, F.; Kravchuk, V. L.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Raduta, Ad. R.

    2013-05-01

    Dissipative 12C+12C reactions at 95 MeV are fully detected in charge with the GARFIELD and RCo apparatuses at Laboratori Nazionali di Legnaro. A comparison to a dedicated Hauser-Feshbach calculation allows us to select events which correspond, to a large extent, to the statistical evaporation of highly excited 24Mg, as well as to extract information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain. Residual deviations from statistical behavior are observed in α yields and attributed to the persistence of cluster correlations well above the 24Mg threshold for six-α decay.

  1. High-precision 27Al/24Mg ratio determination using a modified isotope-dilution approach

    DEFF Research Database (Denmark)

    Paton, Chad; Schiller, Martin; Ulfbeck, David Garf

    2012-01-01

    The precision of the 26Al–26Mg system—one of the most widely used chronometers for constraining the relative timing of events in the early solar system—is presently limited by methods for the determination of 27Al/24Mg ratios, which have seen little improvement in the last decade. We present a no...... on multiple measurements of a ∼2.7 gram piece of the Ivuna CI chondrite, we present a new estimate for the 27Al/24Mg ratio of this meteorite of 0.09781 ± 0.00029....

  2. \\alpha-clustering effects in dissipative 12C+12C reactions at 95 MeV

    CERN Document Server

    Baiocco, G; Gulminelli, F; D'Agostino, M; Bruno, M; Abbondanno, U; Barlini, S; Bini, M; Carboni, S; Casini, G; Cinausero, M; Gramegna, M Degerlier F; Kravchuk, V L; Marchi, T; Olmi, A; Pasquali, G; Piantelli, S; Raduta, Ad R

    2013-01-01

    Dissipative 12C+12C reactions at 95 MeV are fully detected in charge with the GARFIELD and RCo apparatuses at LNL. A comparison to a dedicated Hauser-Feshbach calculation allows to select events which correspond, to a large extent, to the statistical evaporation of highly excited 24Mg, as well as to extract information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain. Residual deviations from a statistical behaviour are observed in \\alpha yields and attributed to the persistence of cluster correlations well above the 24Mg threshold for 6 \\alpha's decay.

  3. Ca isotope fingerprints of early crust-mantle evolution

    Science.gov (United States)

    Kreissig, K.; Elliott, T.

    2005-01-01

    The utility of 40Ca/ 44Ca as a tracer of pre-existing crustal contributions in early Archaean cratons has been explored to identify traces of Hadean crust and to assess the style of continental growth. The relatively short half-life of 40K (˜1.3 Gy) means that its decay to 40Ca occurs dominantly during early Earth History. If Archaean crust had a significant component derived from a more ancient protolith, as anticipated by "steady state" crustal evolution models, this should be clearly reflected in radiogenic 40Ca/ 44Ca ratios (or positive initial ɛ Ca) in different Archaean cratons. A high precision thermal ionisation technique has been used to analyse the 40Ca/ 44Ca ratios of plagioclase separates and associated whole rocks in ˜3.6 Ga (early Archaean) samples from Zimbabwe and West Greenland. Three out of four tonalite, trondhjemite, granodiorite (TTG) suite samples from Zimbabwe display initial 40Ca/ 44Ca ratios indistinguishable from our measured modern MORB value (i.e., ɛ Ca(3.6) ˜ 0). Greenland samples, however, are very diverse ranging from ɛ Ca(3.7) = 0.1 in mafic pillow lavas and felsic sheets from the Isua supracrustal belt, up to very radiogenic signatures (ɛ Ca(3.7) = 2.9) in both mafic rocks of the Akilia association and felsic TTG from the coastal Amîtsoq gneisses. At face value, these results imply the Zimbabwe crust is juvenile whereas most Greenland samples include an earlier crustal component. Yet the west Greenland craton, as with many Archaean localities, has experienced a complex geological history and the interpretation of age-corrected initial isotope values requires great care. Both felsic and mafic samples from Greenland display ɛ Ca(3.7) so radiogenic that they are not readily explained by crustal growth scenarios. The presence of such radiogenic 40Ca/ 44Ca found in low K/Ca plagioclases requires Ca isotope exchange between plagioclase and whole rock during later metamorphic event(s). In addition the unexpectedly radiogenic Ca

  4. Application of Ca stable isotopes to long-term changes in the Ca cycle of a Northern Hardwood forest

    Science.gov (United States)

    Kurtz, A. C.; Takagi, K.; Bailey, S. W.; Bullen, T. D.

    2015-12-01

    The Hubbard Brook Ecosystem Study (New Hampshire, USA) presents an unusual opportunity for the application of innovative isotope methods in forest biogeochemistry. Changes in biogeochemical cycling resulting from decades of acid deposition, subsequent reductions in acid deposition, and a series of experimental treatments (harvesting, Ca amendment) have been studied continuously for 60 years at this site. Importantly, researchers have archived soil, water, and vegetation samples for much of the site's history. Our work seeks to complement earlier mass balance studies of Ca cycling by measuring Ca isotope ratios on archived samples. In the first component of our study, we examined the Ca isotopic response to an experimental clearcut in the early 1980's. Earlier work showed that the clearcut promoted dramatic loss of Ca from the watershed, indicated by a 5-fold increase in streamwater Ca concentrations. The mechanism for this loss was unclear as no resolvable changes in soil Ca pools were observed. Our work shows that streamwater dissolved Ca becomes isotopically lighter as Ca concentrations increase. These data are best accounted for by an increase in Ca loss from the soil cation exchange complex. Soil exchangeable δ44Ca itself evolves towards lighter values in the years following the experimental harvest. We interpret this as replenishment of the soil exchange complex by release of isotopically light Ca from root biomass. In the second component of our study, we examine decadal-scale changes in streamwater and soil Ca in an un-manipulated biogeochemical reference watershed. Historical data from Hubbard Brook show that streamwater Ca concentrations began decreasing sharply in the early 1970's, attributed to decreased deposition of both acidity and Ca with the passage of the Clean Air Act. Preliminary data indicate no resolvable change in the average δ44Ca of streamwater, with variability mostly attributable to discharge (flowpath control). Preliminary data

  5. ISOCHRONS IN PRESOLAR GRAPHITE GRAINS FROM ORGUEIL

    Energy Technology Data Exchange (ETDEWEB)

    Zinner, Ernst; Jadhav, Manavi, E-mail: ekz@wustl.edu [Laboratory for Space Sciences and the Physics Department, Washington University, One Brookings Drive, St. Louis, MO 63130 (United States)

    2013-05-10

    Primitive meteorites contain tiny dust grains that condensed in stellar outflows and explosions. These stardust grains can be extracted from their host meteorites and studied in detail in the laboratory. We investigated depth profiles of the Al-Mg, Ca-K, and Ti-Ca isotopic systems obtained during NanoSIMS isotopic analysis of presolar graphite grains from the CI carbonaceous meteorite Orgueil. Large {sup 26}Al/{sup 27}Al, {sup 41}Ca/{sup 40}Ca, and {sup 44}Ti/{sup 48}Ti ratios, inferred from {sup 26}Mg, {sup 41}K, and {sup 44}Ca excesses from the decay of the short-lived radioisotopes {sup 26}Al, {sup 41}Ca, and {sup 44}Ti, indicate a supernova (SN) origin. From the depth distribution of the radiogenic isotopes and the stable isotopes of their parent elements we constructed isochron-type correlation plots. The plots indicate quantitative retention of radiogenic {sup 26}Mg, {sup 41}K, and {sup 44}Ca in most grains. Deviations from straight lines in the Al-Mg and Ca-K plots can be explained by contamination with {sup 27}Al and isotopically normal Ca, respectively. For the Ti-Ca system in some grains, the lack of parent-daughter correlation indicates either redistribution of radiogenic {sup 44}Ca or heterogeneity in the initial {sup 44}Ti/{sup 48}Ti ratio. We also obtained Si isotopic depth profiles in three graphite grains with large {sup 29}Si and {sup 30}Si excesses, for which a SN origin has been proposed. In two grains no Si-rich subgrains are observed; in the third grain with an apparent Si-rich subgrain the anomalous Si isotopic ratios in the subgrain are the same as in the rest of the graphite host. Our studies show that by measuring depth profiles, information on presolar grains can be obtained that cannot be obtained by whole-grain analysis.

  6. Sr, Ca, and C isotope systematic in small tropical catchments, La Selva, Costa Rica

    Science.gov (United States)

    Wiegand, B. A.; Schwendenmann, L.

    2010-12-01

    Sr, Ca, and C isotopes were analyzed to assess sources and biogeochemical processes affecting surface and groundwater composition of four small catchments located at La Selva Biological Station, Costa Rica. 87Sr/86Sr ratios were employed to quantify inputs from mineral weathering and atmospheric sources. δ13C values of dissolved organic carbon (DOC) and δ44Ca values provide information on biological processes that affect water chemistry. Sr2+ and Ca2+ concentrations of surface and groundwater show large variations due to intermixture of bedrock groundwater with local groundwater [1]. Low 87Sr/86Sr ratios suggest weathering of volcanic rocks as the primary solute source in bedrock groundwater, while atmospheric and in situ weathering contributions are predominant in local groundwater. Contributions of bedrock groundwater constitute > 60 % in the Salto, Saltito and Arboleda catchments, whereas the Taconazo catchment receives atmospheric inputs of > 95 % in addition to local weathering contributions. Surface water and groundwater wells show δ13C-DOC values between -24 ‰ and -30 ‰ due to transfer of organic carbon from the soil zone. δ44Ca values of dissolved Ca2+ in surface and groundwater are considerably fractionated from the input sources rainwater and bedrock groundwater. Light δ44Ca values are preferentially distributed in stream water and shallow groundwater horizons and contrast with heavy Ca isotopes in deeper groundwater wells. Biological processes including plant uptake and decomposition in combination with cation exchange processes in the soils may explain the fractionation of Ca isotopes. [1]Genereux et al., 2009. Water Resour. Res, 45, W08413, doi:10.1029/2008WR007630

  7. Cosmic ray source abundance of calcium

    CERN Document Server

    Perron, C

    1978-01-01

    Re-examines the results of experiments in which ultra-high purity iron targets were irradiated by protons from the two CERN accelerators (600 MeV and 21 GeV); the spallation products were then chemically separated, and their isotopic composition determined by mass spectrometry. Ratios of cross-sections for calcium production by spallation of iron show that /sup 42/Ca, /sup 43/Ca and /sup 44/Ca have about the same abundance, about 10-15% that of iron, confirming earlier studies. (11 refs).

  8. Fractional Absorption of Active Absorbable Algal Calcium (AAACa and Calcium Carbonate Measured by a Dual Stable-Isotope Method

    Directory of Open Access Journals (Sweden)

    Steven A. Abrams

    2010-07-01

    Full Text Available With the use of stable isotopes, this study aimed to compare the bioavailability of active absorbable algal calcium (AAACa, obtained from oyster shell powder heated to a high temperature, with an additional heated seaweed component (Heated Algal Ingredient, HAI, with that of calcium carbonate. In 10 postmenopausal women volunteers aged 59 to 77 years (mean ± S.D., 67 ± 5.3, the fractional calcium absorption of AAACa and CaCO3 was measured by a dual stable isotope method. 44Ca-enriched CaCO3 and AAACa were administered in all subjects one month apart. After a fixed-menu breakfast and pre-test urine collection (Urine 0, 42Ca-enriched CaCl2 was intravenously injected, followed by oral administration of 44Ca-enriched CaCO3 without carrier 15 minutes later, and complete urine collection for the next 24 hours (Urine 24. The fractional calcium absorption was calculated as the ratio of Augmentation of 44Ca from Urine 0 to Urine 24/ augmentation of 42Ca from Urine 0 to Urine 24. Differences and changes of 44Ca and 42Ca were corrected by comparing each with 43Ca. Fractional absorption of AAACa (mean ± S.D., 23.1 ± 6.4, was distinctly and significantly higher than that of CaCO3 (14.7 ± 6.4; p = 0.0060 by paired t-test. The mean fractional absorption was approximately 1.57-times higher for AAACa than for CaCO3. The serum 25(OH vitamin D level was low (mean ± S.D., 14.2 ± 4.95 ng/ml, as is common in this age group in Japan. Among the parameters of the bone and mineral metabolism measured, none displayed a significant correlation with the fractional absorption of CaCO3 and AAACa. Higher fractional absorption of AAACa compared with CaCO3 supports previous reports on the more beneficial effect of AAACa than CaCO3 for osteoporosis.

  9. Lattice effective field theory for nuclei from A = 4 to A = 28

    CERN Document Server

    Lähde, Timo A; Krebs, Hermann; Lee, Dean; Meißner, Ulf-G; Rupak, Gautam

    2013-01-01

    We present an overview of the extension of Nuclear Lattice Effective Field Theory simulations to the regime of medium-mass nuclei. We focus on the determination of the ground-state energies of the alpha nuclei $^{16}$O, $^{20}$Ne, $^{24}$Mg and $^{28}$Si by means of Euclidean time projection.

  10. New method in analysing high-energy {gamma} spectra from heavy ion collisions at projectile energies around 10 MeV/u

    Energy Technology Data Exchange (ETDEWEB)

    Kicinska-Habior, M. [Warsaw Univ., Inst. of Experimental Physics, Warsaw (Poland)]|[University of Washington, Nuclear Physics Laboratory, Seattle (United States); Snover, K.A.; Drebi, Z.; Ye, D.; Kelly, M. [University of Washington, Nuclear Physics Laboratory, Seattle (United States); Maj, A. [University of Washington, Nuclear Physics Laboratory, Seattle (United States)]|[Institute of Nuclear Physics, Cracow (Poland); Trznadel, Z. [Warsaw Univ., Inst. of Experimental Physics, Warsaw (Poland)

    1996-12-31

    The gamma spectra from the giant dipole resonance (GDR) decay have been investigated. It was assumed that the gamma quanta emitted from GDR origin from statistical emission and Bremsstrahlung. The calculation results are compared with the experimental data from {sup 12}C + {sup 26}Mg and {sup 12}C + {sup 24}Mg reactions. 9 refs, 1 fig., 1 tab.

  11. Download this PDF file

    African Journals Online (AJOL)

    Magashi

    2013-06-01

    Jun 1, 2013 ... 18.24 mg/Kg in 2014 for the soil while the vegetables had concentrations in the range of ... Statistical analysis revealed no significant difference in iron levels ... constituent in plants and animals. ... formation of red blood cells.

  12. Reducing the variability of antibiotic production in Streptomyces by cultivation in 24-square deepwell plates

    DEFF Research Database (Denmark)

    Siebenberg, S.; Bapat, Prashant Madhusudhan; Eliasson Lantz, Anna

    2010-01-01

    of time. Originally, novobiocin titers in the deepwell plate (5-12 mg l(-1)) were lower than in Erlenmeyer flasks (24 mg Optimization of the inoculation procedure as well as addition of a siloxylated ethylene oxide/propylene oxide copolymer, acting as oxygen carrier, to the production medium increased...

  13. preliminary phytochemical screening, proximate and elemental ...

    African Journals Online (AJOL)

    DR. AMINU

    tannins (322.9 mg/100g), alkaloids (8.24 mg/100g) and saponins (9.13%). The predominant .... adversely affect protein digestibility but its minimum level required to elicit a .... elements as Sr (69 ± 3.0), Rb (122 ± 0.0) and Zr (11. ± 2.0) in the ...

  14. Isolation of chlorophyll a from spinach leaves

    Directory of Open Access Journals (Sweden)

    E.D. Dikio

    2008-08-01

    Full Text Available An efficient method for separating chlorophyll a from spinach leaves by column chromatography and solvent extraction techniques has been developed. The purity and identity of the chlorophyll a have been confirmed by UV-Vis, IR and mass spectrometry. Yields from 100 g of freeze-dried spinach were 23 – 24 mg of chlorophyll a.

  15. Immediate and long-term effects of opiate antagonists on postictal behaviour following amygdala kindling in the rat

    NARCIS (Netherlands)

    Cotrell, G.A.; Bohus, B.

    1987-01-01

    Male Wistar rats implanted with bipolar electrodes in the amygdaloid complex were kindled. Subcutaneous injection of naloxone or naltrexone in low doses - 0.12 and 0.24 mg/kg, respectively - dramatically reduced the postictal behavioural depression (BD) at 10 or 60 min. Remarkably, the BD was still

  16. Non-statistical Fluctuation of Compound Multiplicity in Nucleus-Nucleus Interactions:Evidence of Strong Intermittency

    Institute of Scientific and Technical Information of China (English)

    Dipak Ghosh; Jayita Ghosh; Mitali Mondal; Swarnapratim Bhattacharyya; Kanchan Kr. Patra; Swarup Ranjan Sahoo; Prabir Kr. Haldar; Argha Deb; Pasupati Mandal; Subrata Biswas; Keya Chattopadhyay; Rinku Sarkar; Ishita Dutta; Biswanath Biswas; Jayanta Roychowdhury

    2002-01-01

    We present a study of the 'compound multiplicity' distribution in terms of scaled factorial moments of orders 2,3, 4 and 5 in 24Mg-AgBr interactions at 4.5 AGeV. The study reveals a strong signal of the intermittent patternof fluctuation in the compound multiplicity distribution.

  17. Immediate and long-term effects of opiate antagonists on postictal behaviour following amygdala kindling in the rat

    NARCIS (Netherlands)

    Cotrell, G.A.; Bohus, B.

    1987-01-01

    Male Wistar rats implanted with bipolar electrodes in the amygdaloid complex were kindled. Subcutaneous injection of naloxone or naltrexone in low doses - 0.12 and 0.24 mg/kg, respectively - dramatically reduced the postictal behavioural depression (BD) at 10 or 60 min. Remarkably, the BD was still

  18. Effect of spirapril and hydrochlorothiazide on platelet function and euglobulin clot lysis time in patients with mild hypertension

    DEFF Research Database (Denmark)

    Fonitz, Gitte (Gleerup); Petersen, J R; Mehlsen, J;

    1996-01-01

    Thirteen patients with mild hypertension (untreated diastolic blood pressure of 95 to 114 mmHg) received, in random order, three successive treatments of four weeks with placebo, spirapril (6 mg daily), or hydrochlorothiazide (HCT2) (24 mg daily). At the end of each treatment, blood samples for a...

  19. Controlled, dose-response study of sertindole and haloperidol in the treatment of schizophrenia

    NARCIS (Netherlands)

    Zimbroff, DL; Kane, JM; Tamminga, CA; Daniel, DG; Mack, RJ; Wozniak, PJ; Sebree, TB; Wallin, BA; Kashkin, KB; Adan, F; Ainslie, G; Allan, E; Atri, P; Baker, R; Beitman, B; Brown, G; Canive, J; Carman, J; Dott, S; Edwards, J; Fenton, W; Freidli, J; Funderburg, L; Ereshefsky, L; Gladson, M; Hamilton, J; Haque, S; Hartford, J; Horne, R; Houck, C; Jampala, C; Labelle, A; Larson, G; Lesem, M; Liskow, B; Makela, E; Moore, N; Morphy, M; Posever, T; Risch, S; Rotrosen, J; Sheehan, D; Silverstone, P; Swann, A; Tapp, A; Thomas, M; Volavka, J; Vora, S

    1997-01-01

    Objective: This multicenter, double-blind, placebo-controlled study evaluated the efficacy and safety of three doses of sertindole (12, 20, and 24 mg/day) and haloperidol (4, 8, and 16 mg/day) in the treatment of psychotic symptoms for 497 hospitalized patients with schizophrenia. Method: The patien

  20. The effect of plant extracts fed before farrowing and during lactation ...

    African Journals Online (AJOL)

    p2492989

    during late pregnancy and lactation had a beneficial effect on the ... Weaner piglets receiving an oregano supplement had a higher weight gain and lower disease ... mg vitamin B2; 2.4 mg vitamin B6; 30 μg vitamin B12; 60 mg biotin; 1.5 mg ...

  1. Are Ti44-Producing Supernovae Exceptional?

    CERN Document Server

    The, L S; Diehl, R; Hartmann, D H; Iyudin, A F; Leising, M D; Meyer, B S; Motizuki, Y; Schönfelder, V

    2006-01-01

    According to standard models supernovae produce radioactive $^{44}$Ti, which should be visible in gamma-rays following decay to $^{44}$Ca for a few centuries. $^{44}Ti production is believed to be the source of cosmic $^{44}$Ca, whose abundance is well established. Yet, gamma-ray telescopes have not seen the expected young remnants of core collapse events. The $^{44}$Ti mean life of $\\tau \\simeq$ 89 y and the Galactic supernova rate of $\\simeq$ 3/100 y imply $\\simeq$ several detectable $^{44}Ti gamma-ray sources, but only one is clearly seen, the 340-year-old Cas A SNR. Furthermore, supernovae which produce much $^{44}Ti are expected to occur primarily in the inner part of the Galaxy, where young massive stars are most abundant. Because the Galaxy is transparent to gamma-rays, this should be the dominant location of expected gamma-ray sources. Yet the Cas A SNR as the only one source is located far from the inner Galaxy (at longitude 112 degree). We evaluate the surprising absence of detectable supernovae fro...

  2. Study of once and twice forbidden {beta} transitions; Contribution a l'etude de transitions {beta} une fois et deux fois interdites

    Energy Technology Data Exchange (ETDEWEB)

    Hocquenghem, J.C. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1967-09-01

    The realisation of an experimental set up for directional angular correlation measurements allowed us to determine {beta} - {gamma} angular correlations. These measurements together with the determination of the {beta} shape-factor have been made for the following transitions: the first forbidden {beta}{sup -} transitions of 386 keV in the {sup 177}Lu disintegration and of 352 keV in the {sup 175}Yb disintegration. The experimental results have been compared with theoretical predictions of the Nilsson's model; the twice forbidden {beta}{sup -} transition of 473 keV in the {sup 94}Nb disintegration. The {beta} transition nuclear matrix elements have been extracted from the experimental results. Comparison have been made with the theoretical values calculated by taking for nuclear wavefunctions those obtained by diagonalization of the residual interaction and assuming that protons and neutrons outside the {sup 90}Zr core are respectively on the 1 g 9/2 and 2 d 5/2 orbits. (author) [French] La realisation d'un ensemble de mesures de correlations angulaires directionnelles nous a permis la mesure de correlations {beta} - {gamma} en fonction de l'energie. En completant celles-ci par la mesure du facteur de forme du spectre {beta}, nous avons pu etudier ainsi: d'une part, les transitions {beta}{sup -} une fois interdites de 386 keV de la desintegration de {sup 177}Lu et de 352 keV de la desintegration de {sup 175}Yb, Les resultats experimentaux ont ete compares aux valeurs calculees dans le modele de Nilsson; d'autre part, la transition {beta}- deux fois interdite de 473 keV de la desintegration de {sup 94}Nb. Les elements de matrice nucleaire de la transition {beta}, extraits des resultats experimentaux, ont ete compares aux valeurs theoriques calculees. Les fonctions d'ondes nucleaires utilisees ont ete obtenues par diagonalisation de l'interaction residuelle en supposant que les protons et les neutrons, en dehors du coeur forme par

  3. Determination of (90)Sr in soil samples using inductively coupled plasma mass spectrometry equipped with dynamic reaction cell (ICP-DRC-MS).

    Science.gov (United States)

    Feuerstein, J; Boulyga, S F; Galler, P; Stingeder, G; Prohaska, T

    2008-11-01

    A rapid method is reported for the determination of (90)Sr in contaminated soil samples in the vicinity of the Chernobyl Nuclear Power Plant by ICP-DRC-MS. Sample preparation and measurement procedures focus on overcoming the isobaric interference of (90)Zr, which is present in soils at concentrations higher by more than six orders of magnitude than (90)Sr. Zirconium was separated from strontium in two steps to reduce the interference by (90)Zr(+) ions by a factor of more than 10(7): (i) by ion exchange using a Sr-specific resin and (ii) by reaction with oxygen as reaction gas in a dynamic reaction cell (DRC) of a quadrupole ICP-MS. The relative abundance sensitivity of the ICP-MS was studied systematically and the peak tailing originating from (88)Sr on mass 90 u was found to be about 3 x 10(-9). Detection limits of 4 fg g(-1) (0.02 Bq g(-1)) were achieved when measuring Sr solutions containing no Zr. In digested uncontaminated soil samples after matrix separation as well as in a solution of 5 microg g(-1) Sr and 50 ng g(-1) Zr a detection limit of 0.2 pg g(-1) soil (1 Bq g(-1) soil) was determined. (90)Sr concentrations in three soil samples collected in the vicinity of the Chernobyl Nuclear Power Plant were 4.66+/-0.27, 13.48+/-0.68 and 12.9+/-1.5 pg g(-1) corresponding to specific activities of 23.7+/-1.3, 68.6+/-3.5 and 65.6+/-7.8 Bq g(-1), respectively. The ICP-DRC-MS results were compared to the activities measured earlier by radiometry. Although the ICP-DRC-MS is inferior to commonly used radiometric methods with respect to the achievable minimum detectable activity it represents a time- and cost-effective alternative technique for fast monitoring of high-level (90)Sr contamination in environmental or nuclear industrial samples down to activities of about 1 Bq g(-1).

  4. Determination of {sup 90}Sr in soil samples using inductively coupled plasma mass spectrometry equipped with dynamic reaction cell (ICP-DRC-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Feuerstein, J.; Boulyga, S.F.; Galler, P.; Stingeder, G. [Department of Chemistry, Division of Analytical Chemistry-VIRIS Laboratory, University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna (Austria); Prohaska, T. [Department of Chemistry, Division of Analytical Chemistry-VIRIS Laboratory, University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna (Austria)], E-mail: thomas.prohaska@boku.ac.at

    2008-11-15

    A rapid method is reported for the determination of {sup 90}Sr in contaminated soil samples in the vicinity of the Chernobyl Nuclear Power Plant by ICP-DRC-MS. Sample preparation and measurement procedures focus on overcoming the isobaric interference of {sup 90}Zr, which is present in soils at concentrations higher by more than six orders of magnitude than {sup 90}Sr. Zirconium was separated from strontium in two steps to reduce the interference by {sup 90}Zr{sup +} ions by a factor of more than 10{sup 7}: (i) by ion exchange using a Sr-specific resin and (ii) by reaction with oxygen as reaction gas in a dynamic reaction cell (DRC) of a quadrupole ICP-MS. The relative abundance sensitivity of the ICP-MS was studied systematically and the peak tailing originating from {sup 88}Sr on mass 90 u was found to be about 3 x 10{sup -9}. Detection limits of 4 fg g{sup -1} (0.02 Bq g{sup -1}) were achieved when measuring Sr solutions containing no Zr. In digested uncontaminated soil samples after matrix separation as well as in a solution of 5 {mu}g g{sup -1} Sr and 50 ng g{sup -1} Zr a detection limit of 0.2 pg g{sup -1} soil (1 Bq g{sup -1} soil) was determined. {sup 90}Sr concentrations in three soil samples collected in the vicinity of the Chernobyl Nuclear Power Plant were 4.66 {+-} 0.27, 13.48 {+-} 0.68 and 12.9 {+-} 1.5 pg g{sup -1} corresponding to specific activities of 23.7 {+-} 1.3, 68.6 {+-} 3.5 and 65.6 {+-} 7.8 Bq g{sup -1}, respectively. The ICP-DRC-MS results were compared to the activities measured earlier by radiometry. Although the ICP-DRC-MS is inferior to commonly used radiometric methods with respect to the achievable minimum detectable activity it represents a time- and cost-effective alternative technique for fast monitoring of high-level {sup 90}Sr contamination in environmental or nuclear industrial samples down to activities of about 1 Bq g{sup -1}.

  5. Cement As a Waste Form for Nuclear Fission Products: The Case of (90)Sr and Its Daughters.

    Science.gov (United States)

    Dezerald, Lucile; Kohanoff, Jorge J; Correa, Alfredo A; Caro, Alfredo; Pellenq, Roland J-M; Ulm, Franz J; Saúl, Andrés

    2015-11-17

    One of the main challenges faced by the nuclear industry is the long-term confinement of nuclear waste. Because it is inexpensive and easy to manufacture, cement is the material of choice to store large volumes of radioactive materials, in particular the low-level medium-lived fission products. It is therefore of utmost importance to assess the chemical and structural stability of cement containing radioactive species. Here, we use ab initio calculations based on density functional theory (DFT) to study the effects of (90)Sr insertion and decay in C-S-H (calcium-silicate-hydrate) in order to test the ability of cement to trap and hold this radioactive fission product and to investigate the consequences of its β-decay on the cement paste structure. We show that (90)Sr is stable when it substitutes the Ca(2+) ions in C-S-H, and so is its daughter nucleus (90)Y after β-decay. Interestingly, (90)Zr, daughter of (90)Y and final product in the decay sequence, is found to be unstable compared to the bulk phase of the element at zero K but stable when compared to the solvated ion in water. Therefore, cement appears as a suitable waste form for (90)Sr storage.

  6. Isoscalar giant monopole resonance in Sn isotopes by Coulomb excitations using a quantum molecular dynamics model

    CERN Document Server

    Tao, C; Zhang, G Q; Cao, X G; Fang, D Q; Wang, H W; Xu, J

    2013-01-01

    The isoscalar giant monopole resonance (ISGMR) in Sn isotopes and other nuclei has been investigated by Coulomb excitations in the framework of the isospin-dependent quantum molecular dynamics (IQMD) model. The spectrum of GMR has been calculated by taking the root-mean-square (RMS) radius of a nucleus as its monopole moment. The peak energy, the full width at half maximum (FWHM), and the strength of GMR extracted by a Gaussian fit to the spectrum have been studied. The GMR peak energies for Sn isotopes from the calculations using a mass-number dependent Gaussian wave-packet width $\\sigma_r$ for nucleons are found to be overestimated and show a weak dependence on the mass number compared with the experimental data. However, it has been found that experimental data of the GMR peak energies for $^{40}$Ca, $^{56}$Ni, $^{90}$Zr and $^{208}$Pb as well as Sn isotopes can be nicely reproduced after taking into account the isospin dependence in isotope chains in addition to the mass number dependence of $\\sigma_r$ fo...

  7. What Do s- and p-Wave Neutron Average Radiative Widths Reveal

    Energy Technology Data Exchange (ETDEWEB)

    Mughabghab, S.F.

    2010-04-30

    A first observation of two resonance-like structures at mass numbers 92 and 112 in the average capture widths of the p-wave neutron resonances relative to the s-wave component is interpreted in terms of a spin-orbit splitting of the 3p single-particle state into P{sub 3/2} and P{sub 1/2} components at the neutron separation energy. A third structure at about A = 124, which is not correlated with the 3p-wave neutron strength function, is possibly due to the Pygmy Dipole Resonance. Five significant results emerge from this investigation: (i) The strength of the spin-orbit potential of the optical-model is determined as 5.7 {+-} 0.5 MeV, (ii) Non-statistical effects dominate the p-wave neutron-capture in the mass region A = 85 - 130, (iii) The background magnitude of the p-wave average capture-width relative to that of the s-wave is determined as 0.50 {+-} 0.05, which is accounted for quantitatively in tenns of the generalized Fermi liquid model of Mughabghab and Dunford, (iv) The p-wave resonances arc partially decoupled from the giant-dipole resonance (GDR), and (v) Gamma-ray transitions, enhanced over the predictions of the GDR, are observed in the {sup 90}Zr - {sup 98}Mo and Sn-Ba regions.

  8. Towards a Microscopic Reaction Description Based on Energy Density Functionals

    Energy Technology Data Exchange (ETDEWEB)

    Nobre, G A; DIetrich, F S; Escher, J E; Thompson, I J; Dupuis, M; Terasaki, J; Engel, J

    2011-09-26

    A microscopic calculation of reaction cross sections for nucleon-nucleus scattering has been performed by explicitly coupling the elastic channel to all particle-hole excitations in the target and one-nucleon pickup channels. The particle-hole states may be regarded as doorway states through which the flux flows to more complicated configurations, and subsequently to long-lived compound nucleus resonances. Target excitations for {sup 40,48}Ca, {sup 58}Ni, {sup 90}Zr and {sup 144}Sm were described in a random-phase framework using a Skyrme functional. Reaction cross sections obtained agree very well with experimental data and predictions of a state-of-the-art fitted optical potential. Couplings between inelastic states were found to be negligible, while the pickup channels contribute significantly. The effect of resonances from higher-order channels was assessed. Elastic angular distributions were also calculated within the same method, achieving good agreement with experimental data. For the first time observed absorptions are completely accounted for by explicit channel coupling, for incident energies between 10 and 70 MeV, with consistent angular distribution results.

  9. A formula used to subtract the effect of gamma-ray of the others to that of measured reaction in measurement of cross section of nuclear reaction and its application

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Abstract According to the regulation of growing and decay of artificial radioactive nuclide, a formula used to subtract the effect of characteristic γ-ray of the others to that of measured reaction was deduced. And then the cross sections of 120Te (n, 2n)119mTe reaction induced by neutrons around 14 MeV were measured by activation relative to the 93Nb (n, 2n)92mNb. In the process of the cross sections measured to be calculated, it was subtracted that the effect of characteristic γ-ray of 126Te (n, p)126Sb to that of measured 120Te (n, 2n)119mTe reaction using the formula deduced. The experimental results were (689±37) and (750±41) mb at the neutron energies of (13.5±0.3) and (14.6±0.3) MeV, respectively. Measurements were carried out by γ-detection using a coaxial HPGe detector. As samples, spectroscopically pure tellurium powder has been used. The fast neutrons were produced by the T(d, n)4He reaction. The neutron energies in these measurements were determined by the method of cross-section ratios between 90Zr (n, 2n) 89m+gZr and 93Nb (n, 2n) 92mNb reactions.

  10. Symmetry Energy III: Isovector Skins

    CERN Document Server

    Danielewicz, Pawel; Lee, Jenny

    2016-01-01

    Isoscalar density is a sum of neutron and proton densities and isovector is a normalized difference. Here, we report on the experimental evidence for the displacement of the isovector and isoscalar surfaces in nuclei, by $\\sim$$0.9 \\, \\text{fm}$ from each other. We analyze data on quasielastic (QE) charge exchange (p,n) reactions, concurrently with proton and neutron elastic scattering data for the same target nuclei, following the concepts of the isoscalar and isovector potentials combined into Lane optical potential. The elastic data largely probe the geometry of the isoscalar potential and the (p,n) data largely probe a relation between the geometries of the isovector and isoscalar potentials. The targets include $^{48}$Ca, $^{90}$Zr, $^{120}$Sn and $^{208}$Pb and projectile incident energy values span the range of (10-50)$\\,\\text{MeV}$. In our fit to elastic and QE charge-exchange data, we allow the values of isoscalar and isovector radii, diffusivities and overall potential normalizations to float away f...

  11. Charge-exchange scattering to the isobaric analog state at medium energies as a probe of the neutron skin

    CERN Document Server

    Loc, Bui Minh; Zegers, R G T

    2014-01-01

    The charge-exchange (3He,t) scattering to the isobaric analog state (IAS) of the target can be considered as "elastic" scattering of 3He by the isovector term of the optical potential (OP) that flips the projectile isospin. Therefore, the accurately measured charge-exchange scattering cross- section for the IAS can be a good probe of the isospin dependence of the OP, which is determined exclusively within the folding model by the difference between the neutron and proton densities and isospin dependence of the nucleon-nucleon interaction. Given the neutron skin of the target is related directly to the same density difference, it can be well probed in the analysis of the charge- exchange (3He,t) reactions at medium energies when the two-step processes can be neglected and the t-matrix interaction can be used in the folding calculation. For this purpose, the data of the (3He,t) scattering to the IAS of 90Zr and 208Pb targets at Elab = 420 MeV have been analyzed in the distorted wave Born approximation using the...

  12. Reaction cross-section predictions for nucleon induced reactions

    CERN Document Server

    Nobre, G P A; Escher, J E; Dietrich, F S

    2010-01-01

    A microscopic calculation of the optical potential for nucleon-nucleus scattering has been performed by explicitly coupling the elastic channel to all the particle-hole (p-h) excitation states in the target and to all relevant pickup channels. These p-h states may be regarded as doorway states through which the flux flows to more complicated configurations, and to long-lived compound nucleus resonances. We calculated the reaction cross sections for the nucleon induced reactions on the targets $^{40,48}$Ca, $^{58}$Ni, $^{90}$Zr and $^{144}$Sm using the QRPA description of target excitations, coupling to all inelastic open channels, and coupling to all transfer channels corresponding to the formation of a deuteron. The results of such calculations were compared to predictions of a well-established optical potential and with experimental data, reaching very good agreement. The inclusion of couplings to pickup channels were an important contribution to the absorption. For the first time, calculations of excitatio...

  13. Coupled-channels calculations of nonelastic cross sections using a density-functional structure model

    CERN Document Server

    Nobre, G P A; Escher, J E; Thompson, I J; Dupuis, M; Terasaki, J; Engel, J

    2010-01-01

    A microscopic calculation of the reaction cross-section for nucleon-nucleus scattering has been performed by explicitly coupling the elastic channel to all particle-hole (p-h) excitation states in the target and to all one-nucleon pickup channels. The p-h states may be regarded as doorway states through which the flux flows to more complicated configurations, and subsequently to long-lived compound nucleus resonances. Target excitations for 40,48Ca, 58Ni, 90Zr and 144Sm were described in a QRPA framework using a Skyrme functional. Reaction cross sections calculated in this approach were compared to predictions of a fitted optical potential and to experimental data, reaching very good agreement. Couplings between inelastic states were found to be negligible, while the couplings to pickup channels contribute significantly. For the first time observed reaction cross-sections are completely accounted for by explicit channel coupling, for incident energies between 10 and 40 MeV.

  14. Chemical analysis of carbon stars in the Local Group: I. The Small Magellanic Cloud and the Sagittarius dwarf spheroidal galaxy

    CERN Document Server

    De Laverny, P; Dominguez, I; Plez, B; Straniero, O; Wahlin, R; Eriksson, K; Jørgensen, U G

    2005-01-01

    We present the first results of our ongoing chemical study of carbon stars in the Local Group of galaxies. We used spectra obtained with UVES at the 8.2 m Kueyen-VLT telescope and a new grid of spherical model atmospheres for cool carbon-rich stars which include polyatomic opacities, to perform a full chemical analysis of one carbon star, BMB-B~30, in the Small Magellanic Cloud (SMC) and two, IGI95-C1 and IGI95-C3, in the Sagittarius Dwarf Spheroidal (Sgr dSph) galaxy. Our main goal is to test the dependence on the stellar metallicity of the s-process nucleosynthesis and mixing mechanism occurring in AGB stars. For these three stars, we find important s-element enhancements with respect to the mean metallicity ([M/H]), namely [s/M]$\\approx$+1.0, similar to the figure found in galactic AGB stars of similar metallicity. The abundance ratios derived between elements belonging to the first and second s-process abundance peaks, corresponding to nuclei with a magic number of neutrons N=50 (88Sr, 89Y, 90Zr) and N=82...

  15. Impact of ENDF/B-VII.0 for AECL applications

    Energy Technology Data Exchange (ETDEWEB)

    Kozier, Ken S.; Altiparmakov, Dimitar V. [AECL - Chalk River Laboratories, Chalk River (Canada)

    2008-07-01

    This paper examines the impact of the new evaluated nuclear data library ENDF/B-VII.0 on selected reactor physics applications at AECL. The twin objectives are to provide feedback to the nuclear data community concerning the practical impact of their work and preliminary guidance to end-users. This work is based on comparison of the results of MCNP simulations with critical measurements involving both the ZED-2 zero power reactor and the MAPLE dedicated isotope production reactors at the Chalk River Laboratories. Significant improvement in the reactivity agreement with the measurements is obtained with ENDF/B-VII.0 for the specific ZED-2 measurements analysed; however, improvements associated with the thermal scattering law data for UO{sub 2} that had been observed initially were subsequently determined to be fortuitous, due to the inadvertent omission of the elastic neutron scattering component. Additionally, the net reactivity impact of major changes to the {sup 90}Zr and {sup 91}Zr capture cross sections with ENDF/B-VII.0 is examined in the MAPLE reactor context and found to be modest due primarily to the offsetting effects of the specific nuclides involved. (authors)

  16. D¯ D meson pair production in antiproton-nucleus collisions

    Science.gov (United States)

    Shyam, R.; Tsushima, K.

    2016-10-01

    We study the D ¯D (D¯0D0 and D-D+) charm meson pair production in antiproton (p ¯) induced reactions on nuclei at beam energies ranging from threshold to several GeV. Our model is based on an effective Lagrangian approach that has only the baryon-meson degrees of freedom and involves the physical hadron masses. The reaction proceeds via the t -channel exchanges of Λc+, Σc+, and Σc++ baryons in the initial collision of the antiproton with one of the protons of the target nucleus. The medium effects on the exchanged baryons are included by incorporating in the corresponding propagators, the effective charm baryon masses calculated within a quark-meson coupling (QMC) model. The wave functions of the bound proton have been determined within the QMC model as well as in a phenomenological model where they are obtained by solving the Dirac equation with appropriate scalar and vector potentials. The initial- and final-state distortion effects have been approximated by using an eikonal approximation-based procedure. Detailed numerical results are presented for total and double differential cross sections for the D¯0D0 and D-D+ production reactions on 16O and 90Zr targets. It is noted that at p ¯ beam momenta of interest to the P ¯ ANDA experiment, medium effects lead to noticeable enhancements in the charm meson production cross sections.

  17. Measurement of fission cross-section for the {sup 232}Th(n,f){sup 141}Ba reaction induced by neutrons around 14 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Lan, Chang-Lin; Fang, Kai-Hong [Lanzhou University, School of Nuclear Science and Technology, Lanzhou, Gansu Province (China); Lanzhou University, Engineering Research Center for Neutron Application, Ministry of Education, Lanzhou, Gansu Province (China); Liu, Shuang-Tong; Lv, Tao; Wang, Qiang; Zhang, Zheng-Wei [Lanzhou University, School of Nuclear Science and Technology, Lanzhou, Gansu Province (China); Lai, Cai-Feng [Chinese Academy of Engineering Physics, Institute of Nuclear Physics and Chemistry, Mianyang, Sichuan Province (China)

    2016-11-15

    The fission cross-section of the {sup 232}Th(n,f){sup 141}Ba reaction induced by neutrons around 14 MeV was measured precisely with the neutron activation and off-line gamma-ray spectrometric technique. Neutron fluence was monitored on-line using the accompanying α-particles from the {sup 3}H({sup 2}H,n){sup 4}He reaction, whereas the neutron energies were measured by the method of cross-section ratios of {sup 90}Zr(n,2n){sup 89}Zr to {sup 93}Nb(n,2n){sup 92m}Nb reactions. The experimentally determined {sup 232}Th(n,f){sup 141}Ba reaction cross-sections were 12.2 ± 0.4 mb at E{sub n} = 14.1 ± 0.3 MeV, 13.0 ± 0.5 mb at E{sub n} = 14.5 ± 0.3 MeV and 13.3 ± 0.5 mb at E{sub n} = 14.7 ± 0.3 MeV, respectively. (orig.)

  18. Nuclear structure studies on medium-heavy mass nuclei using the method of nuclear resonance fluorescence; Kernstrukturuntersuchungen in mittelschweren Atomkernen mit der Methode der Kernresonanzfluoreszenz

    Energy Technology Data Exchange (ETDEWEB)

    Zweidinger, Markus

    2016-06-22

    In the present work the dipole strength distribution in the stable even-even isotopes {sup 92}Zr and {sup 94}Zr is investigated. To excite the nuclei from the ground state to an excited state, real photons are used. This method is called Nuclear Resonance Fluorescence. The measurements were performed at two different setups. The first one is the Darmstadt High Intensity Photon Setup (DHIPS). At DHIPS the measurements yield information about the spin quantum number and the integrated cross section. The second part of the experiments took place at the High Intensity γ-ray Source (HIγS). Here, information about the parity quantum number and the averaged branching ratio of the excited state is accessible. In total, 105 dipole excited states in the nucleus {sup 92}Zr and 124 in the isotope {sup 94}Zr are observed, most of them for the first time. The extracted dipole strength distribution is investigated for the existence of the pygmy dipole resonance that was observed in neighboring nuclei. Furthermore, in previously performed experiments on the isotope {sup 90}Zr, the spin-flip M1 resonance was observed as well. Therefore, also the magnetic dipole strength is investigated. Further, by comparison with global systematics, the two-phonon state is identified. Additionally, the averaged branching ratio is compared to the results of theoretical calculations in the framework of the statistical model.

  19. Consequences of self-consistency violations in Hartree-Fock random-phase approximation calculations of the nuclear breathing mode energy

    CERN Document Server

    Agrawal, B K

    2004-01-01

    We provide for the first time accurate assessments of the consequences of violations of self-consistency in the Hartree-Fock based random phase approximation (RPA) as commonly used to calculate the energy $E_c$ of the nuclear breathing mode. Using several Skyrme interactions we find that the self-consistency violated by ignoring the spin-orbit interaction in the RPA calculation causes a spurious enhancement of the breathing mode energy for spin unsaturated systems. Contrarily, neglecting the Coulomb interaction in the RPA or performing the RPA calculations in the TJ scheme underestimates the breathing mode energy. Surprisingly, our results for the $^{90}$Zr and $^{208}$Pb nuclei for several Skyrme type effective nucleon-nucleon interactions having a wide range of nuclear matter incompressibility ($K_{nm} \\sim 215 - 275$ MeV) and symmetry energy ($J \\sim 27 - 37$ MeV) indicate that the net uncertainty ($\\delta E_c \\sim 0.3$ MeV) is comparable to the experimental one.

  20. Formation of nanophases by crystallization of amorphous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Baricco, M. [Turin Univ. (Italy). Dipt. di Chimica Inorganica; Tiberto, P. [Istituto Elettrotecnico Nazionale, Turin (Italy); Battezzati, L. [Turin Univ. (Italy). Dipt. di Chimica Inorganica

    1995-12-31

    A comparison is made of crystallization mechanisms in Fe-based amorphous alloys (Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 13.5}B{sub 9}, Fe{sub 90}Zr{sub 7}B{sub 3}), which lead to a nanocrystalline bcc phase with peculiar soft magnetic properties through primary crystallization. In all samples, the nucleation takes place uniformely throughout the material. The presence of atoms with low diffusivity (Zr, Nb) reduces the grain growth rate so that a small size of crystals is maintained. On the contrary, even extremely fast heating and short heat treatment do not produce nanocrystals in Fe{sub 40}Ni{sub 40}B{sub 20} although the crystallization mechanism is modified. However milling the ribbon leads to nanostructured crystalline phases. The formation of nanophases by crystallization is discussed considering the temperature dependence of nucleation frequency and growth rate. The effects of various thermodynamic and kinetic parameters are analyzed and the most favourable conditions for nanocrystallization are outlined. (orig.)

  1. Surface area dependence of calcium isotopic reequilibration in carbonates: Implications for isotopic signatures in the weathering zone

    Science.gov (United States)

    Fernandez, N. M.; Druhan, J. L.; Potrel, A.; Jacobson, A. D.

    2016-12-01

    The concept of dynamic equilibrium carries the implicit assumption of continued isotopic exchange between a mineral and the surrounding fluid. While this effect has received much attention in the marine paleoproxy literature, it has been relatively overlooked in application to the terrestrial environment. In weathering systems, a potential consequence is that rapid reequilibration may alter or erase isotopic signatures generated during secondary mineral formation. The extent and timescale over which isotopic signatures are reset in these hydrologic systems is unknown. Using reactive transport modeling, we show isotopic reequilibration under conditions reflecting terrestrial hydrologic settings to be significant and dependent on the reactive surface area of the solid. In particular, we suggest that the non-traditional stable isotopes commonly used in application to carbonates (e.g., Ca, Mg, Sr) are sensitive to these effects due to their rapid reaction rates. We aim to characterize the dependence of Ca isotopic reequilibration on surface area during calcite precipitation via batch experiments conducted at ambient temperature over 48-hour time periods. Calcite precipitation was performed in a closed batch reactor utilizing a controlled free-drift method. The batch reactors contained mixed supersaturated solutions of CaCl2 and NaHCO3 at an initial pH of 8.54. Precipitation was initiated by seed inoculation of calcite crystals with two distinct, pre-constrained surface areas. All experiments achieved the same final state of chemical equilibrium, but as expected, the fastest approach to equilibrium occurred for experiments employing calcite seeds with the highest surface area. This implies that differences in equilibrated Ca isotope ratios (δ44/40Ca) should reflect differences in surface area. This prediction is upheld by models of the experiments, indicating a measureable difference in δ44Ca during calcite precipitation where the higher surface area corresponds to

  2. Determination of component mobilities in bimineralic reaction rims using isotopically doped starting materials

    Science.gov (United States)

    Joachim, Bastian; Abart, Rainer; Höschen, Carmen; Heinrich, Wilhelm

    2013-04-01

    Rim growth experiments were performed between monticellite (CaMgSiO4) single crystals and wollastonite (CaSiO3) powder at 900° C and 1.2 GPa to produce bimineralic diopside (CaMgSi2O6) + merwinite (Ca3MgSi2O8) reaction rims. Symmetrical makeup of the internal rim microstructure implies that rims grow from the original interface towards both reactants at identical rates, indicating that solely MgO-diffusion controls overall rim growth with logD (MgO) = -16.3 ± 0.2 m2s-1 (Joachim et al. 2012). Presence of ppm-amounts of water significantly affects the internal rim microstructure. At "very dry" condition, a lamellar microstructure of alternating palisade-shaped diopside and merwinite grains elongated normal to the reaction front is generated, indicating that CaO and SiO2-mobilities are significantly smaller compared to the MgO-mobility. In presence of minute amounts of water a segregated multilayer microstructure with almost perfectly monomineralic merwinite - diopside - merwinite layers oriented parallel to the reaction front develops, indicating a sufficient additional mobility of either CaO or SiO2 compared to MgO. We used isotopically doped wollastonite (44Ca29SiO3) to identify, which component mobility, CaO or SiO2, is enhanced in presence of ppm amounts of water. Both, 44Ca stemming from the wollastonite as well as 40Ca stemming from the monticellite are distributed across the entire rim. In addition to that, small amounts of 40Ca are found within the wollastonite and substantial amounts of 44Ca are found in the monticellite starting material. In contrast to that, 28Si and 29Si remain in the regions that were originally occupied by their respective source materials monticellite and wollastonite, indicating that the SiO2-mobility is comparatively low. This suggests that the presence of small amounts of water significantly enhances the relative mobility of CaO. Consequently minute amounts of water may not only affect overall rim growth kinetics but also the

  3. Competition between quasi-molecular resonances and fusion-fission in light dinuclear systems

    CERN Document Server

    Beck, C

    1999-01-01

    The results presented in this paper clearly suggest that a coherent framework may exist which connects the topics of heavy-ion molecular resonances, hyperdeformation effects, and fission shape isomerism. New data on particle-particle-$\\gamma$ triple coincidences of the $^{28}$Si+$^{28}$Si reaction at a beam energy corresponding to the population of a conjectured J$^{\\pi}$ = 38$^{+}$ resonance in $^{56}$Ni are presented. The absence of alignment of the spins of the outgoing fragments with respect to the orbital angular momentum is found to be in contrast with the alignment as measured for the $^{24}$Mg+$^{24}$Mg resonances. A molecular-model picture is presented to suggest a "butterfly" motion of two oblate $^{28}$Si nuclei interacting in a equator-to-equator molecular configuration.

  4. Investigations of astrophysically interesting nuclear reactions by the use of gas target techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, J.W. [Inst. fuer Strahlenphysik, Univ. Stuttgart, Stuttgart (Germany)

    1998-06-01

    A brief review of the common properties of windowless and recirculating gas targets is presented. As example the Stuttgart gas target facility Rhinoceros in the extended and in the supersonic jet mode with its properties and techniques is explained, also with respect to gas purification techniques. Furthermore several typical experiments from the field of nuclear astrophysics with characteristic results are described (D({alpha},{gamma}){sup 6}Li, {sup 15}N({alpha},{gamma}){sup 19}F, {sup 16}O(p,{gamma}){sup 17}F, {sup 16}O({alpha},{gamma}){sup 20}Ne, {sup 20}Ne({alpha},{gamma}){sup 24}Mg, {sup 21}Ne({alpha},n){sup 24}Mg, {sup 18}O({alpha},n){sup 21}Ne, {sup 17}O({alpha},n){sup 20}Ne). In several cases the experimental sensitivity could be raised by up to a factor of 10{sup 6}. (orig.)

  5. The 12C(12C,α)20Ne and 12C(12C,p)23Na reactions at the Gamow peak via the Trojan Horse Method

    Science.gov (United States)

    Tumino, A.; Spitaleri, C.; Cherubini, S.; Guardo, L.; Gulino, M.; Indelicato, I.; La Cognata, M.; Lamia, L.; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; Sergi, M. L.; Spartá, R.

    2016-05-01

    A measurement of the 12C(14N,α20Ne)2H and 12C(14N,p23Na)2Hreactions has been performed at a 14N beam energy of 30.0 MeV. The experiment aims to explore the extent to which contributing 24Mg excited states can be populated in the quasi-free reaction off the deuteron in 14N. In particular, the 24Mg excitation region explored in the measurement plays a key role in stellar carbon burning whose cross section is commonly determined by extrapolating high-energy fusion data. From preliminary results, α and proton channels are clearly identified. In particular, ground and first excited states of 20Ne and 23Na play a major role.

  6. Molecular resonances and the Jacobi shape transition in {sup 48}Cr

    Energy Technology Data Exchange (ETDEWEB)

    Salsac, M-D; Haas, F; Courtin, S; Beck, C; Lebhertz, D [IPHC, Universite Louis Pasteur, CNRS-IN2P3, Strasbourg (France); Algora, A; Dombradi, Z [INR, Debrecen (Hungary); Beghini, S; Farnea, E; Lenzi, S; Montagnoli, G [Universita di Padova and INFN, Padova (Italy); Behera, Br; Corradi, L; Fioretto, E; Gadea, A; Latina, A; Marginean, N [INFN Laboratori Nazionali di Legnaro, Legnaro (Italy); Chapman, R; Liang, X [University of Paisley, Paisley (United Kingdom); Jenkins, D G [University of York, York (United Kingdom)], E-mail: marie-delphine.salsac@ires.in2p3.fr (and others)

    2008-05-15

    The {sup 24}Mg + {sup 24}Mg reaction has been studied at the Legnaro Tandem at a CM bombarding energy of 45.7 MeV where a narrow and high spin resonance has been reported previously. The decay of the resonance into the inelastic and fusion-evaporation channels has been investigated. The ON and OFF resonance decay yields have been measured using, for the inelastic channels, the fragment spectrometer PRISMA and the {gamma} array CLARA, and, for the fusion-evaporation channels, the Si array EUCLIDES and the {gamma} array GASP The resonant effects observed in both experiments are discussed and it is suggested that the resonance populates a deformed {sup 48}Cr after a Jacobi shape transition.

  7. High-spin states in the odd-odd nucleus {sup 80}Y

    Energy Technology Data Exchange (ETDEWEB)

    Bucurescu, D. E-mail: bucurescu@tandem.nipne.ro; Ur, C.A.; Ionescu-Bujor, M.; Iordachescu, A.; Bazzacco, D.; Brandolini, F.; De Angelis, G.; De Poli, M.; Gadea, A.; Lunardi, S.; Marginean, N.; Medina, N.H.; Napoli, D.R.; Pavan, P.; Rossi Alvarez, C.; Spolaore, P

    2002-07-01

    The high-spin states of {sup 80}Y have been studied with the reactions {sup 24}Mg({sup 58}Ni, pn{gamma}) at 180 MeV and {sup 58}Ni({sup 24}Mg, pn{gamma}) at 77 MeV. Gamma-ray transitions in this nucleus have been unambiguously assigned by using the GASP detector array in conjunction with the recoil mass spectrometer CAMEL and the ISIS Silicon detector ball. These transitions have been arranged into several rotational bands extending up to an excitation energy of about 12 MeV and spin 24 {Dirac_h}. The bands are discussed within the framework of the interacting boson-fermion-fermion and cranked shell models.

  8. Cluster correlation effects in 12C+12C and 14N+10B fusion-evaporation reactions

    Directory of Open Access Journals (Sweden)

    Morelli L.

    2015-01-01

    Full Text Available The decay of highly excited states of 24Mg is studied in fusion evaporation events completely detected in charge in the reactions 12C+12C and 14N+10B at 95 and 80 MeV incident energy respectively. The comparison of light charged particles measured spectra with statistical model predictions suggests that the dominant reaction mechanism is compound nucleus (CN formation and decay. However, in both reactions, a discrepancy with statistical expectations is found for α particles detected in coincidence with Carbon, Oxigen and Neon residues. The comparison between the two reactions shows that this discrepancy is only partly explained by an entrance channel effect. Evidence for cluster correlations in excited 24Mg CN is suggested by the comparison between the measured and calculated branching ratios for the channels involving α particles.

  9. High-precision Mg isotope measurements of terrestrial and extraterrestrial material by HR-MC-ICPMS—implications for the relative and absolute Mg isotope composition of the bulk silicate Earth

    DEFF Research Database (Denmark)

    Bizzarro, Martin; Paton, Chad; Larsen, Kirsten Kolbjørn

    2011-01-01

    shergottite and sea water samples. Repeated analyses of terrestrial and extraterrestrial samples demonstrate that it is possible to routinely measure the relative Mg-isotope composition of silicate materials with an external reproducibility of 2.5 and 20 ppm for the m26Mg* and m25Mg values, respectively (m......-isotope composition for Earth’s mantle – and hence that of the bulk silicate Earth – to be 25Mg/24Mg 1/4 0.126896 ¿ 0.000025 and 26Mg/24Mg 1/4 0.139652 ¿ 0.000033. Given the restricted range of m25Mg obtained for bulk planetary material by the sample-standard bracketing technique and the excellent agreement between...

  10. C-burning via the Trojan horse method

    Science.gov (United States)

    Tumino, A.; Spitaleri, C.; Cherubini, S.; Guardo, L.; Gulino, M.; Indelicato, I.; La Cognata, M.; Lamia, L.; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; Sergi, M. L.; Spartá, R.

    2017-06-01

    The 12C(14N,α20Ne)2H and 12C(14N,p23Na)2H reactions have been measured at a 14N beam energy of 30.0 MeV. The experiment aims to explore 24Mg excited states that can be populated in the quasi-free reaction off the deuteron in 14N. In particular, the 24Mg excitation region explored in the measurement plays a key role in stellar carbon burning whose cross section is obtained by extrapolating high-energy fusion data. From preliminary results, α and proton channels are clearly identified. In particular, ground and first excited states of 20Ne and 23Na play a major role.

  11. Restoration of rotational symmetry in deformed relativistic mean-field theory

    Institute of Scientific and Technical Information of China (English)

    YAO Jiang-Ming; MENG Jie; Pena Arteaga Daniel; Ring Peter

    2009-01-01

    We report on a very recently developed three-dimensional angular momentum projected relativistic mean-field theory with point-coupling interaction (3DAMP+RMF-PC). Using this approach the same effective nucleon-nucleon interaction is adopted to describe both the single-particle and collective motions in nuclei.Collective states with good quantum angular momentum are built projecting out the intrinsic deformed meanfield states. Results for 24Mg are shown as an illustrative application.

  12. Particulate organic matter in shelf waters of Prinsesse Asrid Kyst, Antarctica

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.; Bhosle, N.B.

    In the coastal and estuarine waters of Goa, particulate organic carbon (POC) varied from 0.52 to 2.51 mg l-1 and from 0.28 to 5.24 mg l-1 and particulate phosphorus (PP) varied from 0.71 to 5.18 mu g l-1 and from 0.78 to 20.34 mu g l-1, respectively...

  13. Particulate organic matter in the coastal and estuarine waters of Goa and its relationship with phytoplankton production

    Digital Repository Service at National Institute of Oceanography (India)

    Verlecar, X.N.; Qasim, S.Z.

    In the coastal and estuarine waters of Goa, particulate organic carbon (POC) varied from 0.52 to 2.51 mg l-1 and from 0.28 to 5.24 mg l-1 and particulate phosphorus (PP) varied from 0.71 to 5.18 mu g l-1 and from 0.78 to 20.34 mu g l-1, respectively...

  14. Developmental neurotoxicity of propylthiouracil in rats

    DEFF Research Database (Denmark)

    Petersen, Marta Axelstad; Hansen, Pernille Reimer; Christiansen, Sofie

    2007-01-01

    . The overall aim was to provide detailed knowledge on the relationship between effects on thyroid hormone levels and long-lasting developmental neurotoxicity effects. Groups of 16–18 pregnant rats (HanTac:WH) were dosed with PTU (0, 0.8, 1.6 or 2.4 mg/(kg day)) from gestation day 7 to postnatal day (PND) 16...... behaviour and hearing function. This supports that exposure to TDC's in general may cause long-lasting developmental neurotoxicity....

  15. Resolved Sideband Spectroscopy for the Detection of Weak Optical Transitions

    Science.gov (United States)

    2013-08-01

    Kermit Murray, Kathy O’Neal, Paige x 12 Patterson, Robert Perlis, Erwin Poliakoff, Leonard Richardson, Kresimir Rupnik, David Sherrill, and Cathy...24Mg+,” Phys. Rev. Lett. 102, 013006 (2009). [33] T. Rosenband, P. O. Schmidt, D. B. Hume , W. M. Itano, T. M. Fortier, J. E. Stalnaker, K. Kim, S. A...2007). [34] T. Rosenband, D. B. Hume , P. O. Schmidt, C. W. Chou, A. Brusch, L. Lorini, W. H. Oskay, R. E. Drullinger, T. M. Fortier, J. E. Stalnaker

  16. Quantitative Ischemia Detection During Cardiac MR Stress Testing

    Science.gov (United States)

    2007-11-02

    of Health, Bethesda, MD, USA 4 Cardiology Division of the School of Medicine, Johns Hopkins University, Baltimore, MD, USA Abstract- Because ECG...independent detection of the onset of ischemia during acute coronary occlusion. Six mongrel dogs underwent acute coronary artery ischemia of 2 minutes...revised 1985). Six mongrel dogs (20-25 kgs) were preanesthetized with 10 mg/kg ketamine, 2.4 mg/kg xylazine, and 0.02 mg/kg atropine intramuscularly

  17. First identification of excited states in {sup 59}Zn

    Energy Technology Data Exchange (ETDEWEB)

    Andreoiu, C.; Ekman, J.; Fahlander, C.; Mineva, M.N.; Rudolph, D. [Department of Physics, Lund University, S-22100 Lund (Sweden); Axiotis, M.; Angelis, G. de; Farnea, E.; Gadea, A.; Kroell, T.; Martinez, T. [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro (Italy); Lenzi, S.M.; Rossi Alvarez, C. [Dipartamento di Fisica dell' Universita and INFN, Sezione di Padova, I-35131 Padova (Italy); Marginean, N. [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro (Italy); National Institute for Physics and Nuclear Engineering-' ' Horia Hulubei' ' , RO-76900, Bucharest (Romania); Ur, C.A. [Dipartamento di Fisica dell' Universita and INFN, Sezione di Padova, I-35131 Padova (Italy)

    2002-12-01

    Excited states in {sup 59}Zn were observed for the first time following the fusion-evaporation reaction {sup 24}Mg+{sup 40}Ca at a beam energy of 60 MeV. The GASP array in conjunction with the ISIS Silicon ball and the NeutronRing allowed for the detection of {gamma}-rays in coincidence with evaporated light particles. The mirror symmetry of {sup 59}Zn and {sup 59}Cu is discussed. (orig.)

  18. Polarization measurements of proton capture gamma rays

    NARCIS (Netherlands)

    Suffert, M.; Endt, P.M.; Hoogenboom, A.M.

    1959-01-01

    The linear polarization has been measured of eight different gamma rays of widely differing energies (Eγ = 0.8 - 8.0 MeV) emitted at resonances in the 24Mg(p, γ)25Al, 30Si(p, γ)31P, and 32S(p, γ)33Cl reactions. The gamma rays emitted at 90° to the proton beam were Compton scattered in a 2″ NaI scint

  19. Atomic displacements in ferroelectric trigonal and orthorhombic boracite structures

    Science.gov (United States)

    Dowty, Eric; Clark, J.R.

    1972-01-01

    New crystal-structure refinements of Pca21 boracite, Mg3ClB7O13, and R??{lunate}c ericaite, Fe2.4Mg0.6ClB7O13, show that some boron and oxygen atoms are involved in the 'ferro' transitions as well as the metal and halogen atoms. The atomic displacements associated with the polarity changes are as large as 0.6A??. ?? 1972.

  20. Measurements of proton induced γ-ray emission cross sections on MgF{sub 2} target in the energy range 1.95–3.05 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Zamboni, I., E-mail: izamboni@irb.hr; Siketić, Z.; Jakšić, M.; Bogdanović Radović, I.

    2015-01-01

    Highlights: • We measured PIGE differential cross sections for F and Mg between 1.95 and 3.05 MeV with 15 keV step. • In general good agreement was found with the data available from the literature. • We observed resonance in the {sup 24}Mg(p,pγ{sub 1−0}){sup 24}Mg reaction at 2.01 MeV, which is well-suited for depth profiling of Mg. - Abstract: In this work we present differential cross sections for γ-ray emission from the reactions {sup 19}F(p,p′γ){sup 19}F (E{sub γ} = 110, 197, 1236 and 1349 + 1357 keV), {sup 24}Mg(p,p′γ){sup 24}Mg (E{sub γ} = 1369 keV) and {sup 25}Mg(p,p′γ){sup 25}Mg (E{sub γ} = 390, 585 and 975 keV). Differential cross sections were measured for proton energies from 1.95 to 3.05 MeV with a 15 keV step and beam energy resolution of 0.06%. Thin reference standard, 54.1 μg/cm{sup 2} of MgF{sub 2} deposited on thin Mylar foil with additionally evaporated 4 nm Au layer, was used as a target. The γ-rays were detected by a 20% relative efficiency HPGe detector placed at an angle of 135° with respect to the beam direction, while the backscattered protons were collected using silicon surface barrier detector placed at the scattering angle of 165°. Obtained cross sections were compared with the previously measured data available from the literature.

  1. Pharmacokinetics of a novel submicron budesonide dispersion for nebulized delivery in asthma.

    Science.gov (United States)

    Shrewsbury, Stephen B; Bosco, Andrew P; Uster, Paul S

    2009-01-01

    The objective of this study was to evaluate the safety and pharmacokinetics of unit dose budesonide (UDB), an aqueous dispersion of submicron-sized budesonide particles, and a commercially available budesonide suspension formulation. This was a randomized, double-blind, active-controlled, 4-period, 4-way crossover trial in 16 healthy, adult volunteers. Subjects received UDB 0.24, 0.12, and 0.06 mg or commercial budesonide 0.25 mg via a jet nebulizer. T(max) was significantly (p<0.05) earlier for UDB 0.06, 0.12, and 0.24 mg (4.5+/-3.3, 3.1+/-1.5, 3.7+/-1.5 min) vs. commercial budesonide (9.1+/-7.1 min). C(max) was significantly (p<0.05) higher for UDB 0.24 mg vs. commercial budesonide 0.25 mg (434.5+/-246.9 pg/mL vs. 303.5+/-177.4 pg/mL) but not between UDB 0.12 mg (239.9+/-140 pg/mL) and commercial budesonide 0.25 mg (p=0.448). AUC(0-infinity) was marginally, but significantly lower for UDB 0.24 mg than commercial budesonide 0.25 mg. AUCs for UDB 0.12 mg were lower than commercial budesonide 0.25 mg. UDB 0.24 mg was absorbed more rapidly and achieved higher peak concentrations than commercial budesonide 0.25 mg, but had a lower AUC(0-infinity). UDB 0.12 mg also was absorbed more rapidly but had lower C(max) and AUCs than commercial budesonide 0.25 mg.

  2. Probing clustering in excited alpha-conjugate nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Borderie, B., E-mail: borderie@ipno.in2p3.fr [Institut de Physique Nucléaire, CNRS/IN2P3, Univ. Paris-Sud, Université Paris-Saclay, Orsay (France); Raduta, Ad.R. [Institut de Physique Nucléaire, CNRS/IN2P3, Univ. Paris-Sud, Université Paris-Saclay, Orsay (France); National Institute for Physics and Nuclear Engineering, Bucharest-Magurele (Romania); Ademard, G.; Rivet, M.F. [Institut de Physique Nucléaire, CNRS/IN2P3, Univ. Paris-Sud, Université Paris-Saclay, Orsay (France); De Filippo, E. [INFN, Sezione di Catania (Italy); Geraci, E. [INFN, Sezione di Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania (Italy); INFN, Sezione di Bologna and Dipartimento di Fisica, Università di Bologna (Italy); Le Neindre, N. [Institut de Physique Nucléaire, CNRS/IN2P3, Univ. Paris-Sud, Université Paris-Saclay, Orsay (France); LPC, CNRS/IN2P3, Ensicaen, Université de Caen, Caen (France); Alba, R.; Amorini, F. [INFN, Laboratori Nazionali del Sud, Catania (Italy); Cardella, G. [INFN, Sezione di Catania (Italy); Chatterjee, M. [Saha Institute of Nuclear Physics, Kolkata (India); Guinet, D.; Lautesse, P. [Institut de Physique Nucléaire, CNRS/IN2P3, Univ. Claude Bernard Lyon 1, Université de Lyon, Villeurbanne (France); La Guidara, E. [INFN, Sezione di Catania (Italy); CSFNSM, Catania (Italy); Lanzalone, G. [INFN, Laboratori Nazionali del Sud, Catania (Italy); Facoltá di Ingegneria e Architettura, Università Kore, Enna (Italy); Lanzano, G. [INFN, Sezione di Catania (Italy); and others

    2016-04-10

    The fragmentation of quasi-projectiles from the nuclear reaction {sup 40}Ca+{sup 12}C at 25 MeV per nucleon bombarding energy was used to produce α-emission sources. From a careful selection of these sources provided by a complete detection and from comparisons with models of sequential and simultaneous decays, evidence in favor of α-particle clustering from excited {sup 16}O, {sup 20}Ne and {sup 24}Mg is reported.

  3. Effect of microneedle on the pharmacokinetics of ketoprofen from its transdermal formulations.

    Science.gov (United States)

    So, Jae-Woo; Park, Hyoun-Hyang; Lee, Seung S; Kim, Dong-Chool; Shin, Sang-Chul; Cho, Cheong-Weon

    2009-01-01

    Non-invasive transdermal delivery using microneedle arrays was recently introduced to deliver a variety of large and hydrophilic compounds into the skin, including proteins and DNA. In this study, a microneedle array was applied to the delivery of a hydrophobic drug, ketoprofen, to determine if transdermal delivery in rats can be improved without the need for permeation enhancers. The ability of a microneedle to increase the skin permeability of ketoprofen was tested using the following procedure. A microneedle array was inserted into the lower back skin of a rat using a clip for 10 min. Subsequently, 24 mg/kg of a ketoprofen gel was loaded on the same site where the microneedle had been applied. Simultaneously, the microneedle was coated with 24 mg/kg of a ketoprofen gel, and inserted into the skin using a clip for 10 min. As a negative control experiment, only 24 mg/kg of the ketoprofen gel was applied to the shaved lower back of a rat. Blood samples were taken at the indicated times. The plasma concentration (C(p)) was obtained as a function of time (t), and the pharmacokinetic parameters were calculated using the BE program. The group loaded with the microneedle coated with ketoprofen gel showed a 1.86-fold and 2.86-fold increase in the AUC and C((max)) compared with the ketoprofen gel alone group. These results suggest that a microneedle can be an ideal tool for transdermal delivery products.

  4. Molecular resonance phenomena and alpha-clustering recent progress and perspectives

    CERN Document Server

    Beck, C

    2004-01-01

    The connection between molecular resonance phenomena in light heavy-ion collisions, alpha-clustering and extremely deformed states in light $\\alpha$-like nuclei is discussed. For example, the superdeformed bands recently discovered in light N=Z nuclei such as $^{36}$Ar, $^{40}$Ca, $^{48}$Cr, and $^{56}$Ni by $\\gamma$-ray spectroscopy may have a special link with resonant states in collisions with $\\alpha$-like nuclei. The resonant reactions involving identical bosons such as $^{12}$C+$^{12}$C, $^{16}$O+$^{16}$O $^{24}$Mg+$^{24}$Mg and $^{28}$Si+$^{28}$Si are of interest. For instance, a butterfly mode of vibration of the J$^{\\pi}$ = 38$^{+}$ resonance of $^{28}$Si+$^{28}$Si has been discovered in recent particle $\\gamma$-ray angular correlations measurements. The search for signatures of strongly deformed shapes and clustering in light N=Z nuclei is also the domain of charged particle spectroscopy. The investigation of $\\gamma$-decays in $^{24}$Mg has been undertaken for excitation energies where previously n...

  5. Breakup studies with {sup 23}Na

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, N.S.; Watson, D.L.; Gyapong, G.J.; Jones, C.D. [University of York, York YO1 5DD (United Kingdom); Bennett, S.J.; Freer, M.; Fulton, B.R.; Karban, O.; Murgatroyd, J.T.; Tungate, G. [University of Birmingham, Birmingham, B15 2TT (United Kingdom); Rae, W.D.M.; Smith, A.E. [University of Oxford, Oxford, OX1 3RA (United Kingdom)

    1995-05-01

    The breakup of {sup 23}Na nuclei into {sup 11}B+{sup 12}C and of {sup 24}Mg nuclei into {sup 12}C+{sup 12}C has been studied using the reactions {sup 12}C({sup 23}Na,{sup 11}B{sup 12}C){sup 12}C and {sup 12}C({sup 23}Na,{sup 12}C{sup 12}C){sup 11}B. Clear evidence was found for the breakup of the {sup 23}Na and {sup 24}Mg nuclei into the ground states of both fragments. The yieldrotect from the {sup 12}C({sup 23}Na,{sup 11}B{sub g.s.}{sup 12}C{sub g.s.}){sup 12}C{sub g.s.} reaction was concentrated in the region of excitationrotect energy in {sup 23}Na between 24 and 28 MeV and fragmented among a number of states. Therotect {sup 12}C({sup 23}Na,{sup 12}C{sub g.s.} {sup 12}C{sub g.s.)}{sup 11}B{sub g.s.} reaction was found to proceed chiefly via broad states at 22.1 and 23.9 MeV in {sup 24}Mg.

  6. Decay of the excited compound system *56Ni formed through various channels using deformed Coulomb and deformed nuclear proximity potentials

    Science.gov (United States)

    Santhosh, K. P.; Subha, P. V.

    2017-06-01

    The total cross section, the intermediate mass fragment (IMF) production cross section, and the cross section for the formation of light particles (LPs) for the decay of compound system *56Ni formed through the entrance channel 32S+24Mg have been evaluated by taking the scattering potential as the sum of deformed Coulomb and deformed nuclear proximity potentials, for various Ec .m . values. The computed results have been compared with the available experimental data of total cross section corresponding to Ec .m .=60.5 and 51.6 MeV for the entrance channel 32S+24Mg , which were found to be in good agreement. The experimental values for the LP production cross section and IMF cross section for the channel 32S+24Mg were also found to agree with our calculations. Hence we have extended our studies and have thus computed the total cross section, IMF cross section, and LP cross section for the decay of *56Ni formed through the other three entrance channels 36Ar+20Ne,40Ca+16O , and 28Si+28Si with different Ec .m . values. Hence, we hope that our predictions on the evaluations of the IMF cross sections and the LP cross sections for the decay of *56Ni formed through these three channels can be used for further experimental studies.

  7. Effects of selenium on the growth and photosynthetic characteristics of flue-cured tobacco (Nicotiana tabacum L.

    Directory of Open Access Journals (Sweden)

    Chaoqiang Jiang

    2015-03-01

    Full Text Available The objective of this study was to investigate the effect of Selenium (Se supply (0, 3, 6, 12, 24 mg kg−1 on the growth, photosynthetic characteristics, Se accumulation and distribution of flue-cured tobacco (Nicotiana tabacum L.. Results showed that low-dose Se treatments (≤6 mg kg−1 stimulated plant growth but high-dose Se treatments (≥12 mg kg−1 hindered plant growth. Optimal Se dose (6 mg kg−1 stimulated plant growth by reducing MDA content and improving photosynthetic capability. However, excess Se (24 mg kg−1 increased MDA content by 28%, decreased net photosynthetic rate and carboxylation efficiency by 34% and 39%, respectively. The Se concentration in the roots, stems, and leaves of the tobacco plants significantly increased with increasing Se application. A linear correlation (R = 0.95, P leaf > stem. The Se concentration in the roots was 3.17 and 7.57 times higher than that in the leaves and stems, respectively, after treatment with 24 mg kg−1 Se. In conclusion, the present study suggested that optimal Se dose (6 mg kg−1 improved the plant growth mainly by enhancing photosynthesis, stomatal conductance, carboxylation efficiency and Rubisco content in the flue-cured tobacco leaves. However, the inhibition of excess Se on tobacco growth might be due to high accumulation of Se in roots and the damage of photosynthesis in leaves.

  8. Study 2 of Scientists and Engineers in the DoD Laboratories

    Science.gov (United States)

    1990-07-01

    00 4) bj 4 o~~5 U,4 Q~b 04~1 0 4) 0c:W. ~ . 4)4 4-1 CA 4) barAc 4)b . ~ .t*W 44 ca 0 0 40 .C:4 CuCA ca~~ . 4) ai 4) A )0 a , - - 0𔃼 .0V 0 02~ ~ ~ . uU...U 00 C,4~ 91.U 0 4)u’ C) 0 . 0~ P"CA00 (A UA Q 0 0 r- x _u Cuca ~ ý: r- cnu~U m0 * s ’.0 V). Cd2 em. 00 00 U 00 U (U-U eoh 0 (U.0 9:6I (U 4)), 4j *4

  9. Measurement of isospin mixing at a finite temperature in 80Zr via giant dipole resonance decay

    Science.gov (United States)

    Corsi, A.; Wieland, O.; Barlini, S.; Bracco, A.; Camera, F.; Kravchuk, V. L.; Baiocco, G.; Bardelli, L.; Benzoni, G.; Bini, M.; Blasi, N.; Brambilla, S.; Bruno, M.; Casini, G.; Ciemala, M.; Cinausero, M.; Crespi, F. C. L.; D'Agostino, M.; Degerlier, M.; Giaz, A.; Gramegna, F.; Kmiecik, M.; Leoni, S.; Maj, A.; Marchi, T.; Mazurek, K.; Meczynski, W.; Million, B.; Montanari, D.; Morelli, L.; Myalski, S.; Nannini, A.; Nicolini, R.; Pasquali, G.; Poggi, G.; Vandone, V.; Vannini, G.

    2011-10-01

    Isospin mixing in the hot compound nucleus 80Zr was studied by measuring and comparing the γ-ray emission from the fusion reactions 40Ca+40Ca at Ebeam=200 MeV and 37Cl+44Ca at Ebeam=153 MeV. The γ yield associated with the giant dipole resonance is found to be different in the two reactions because, in self-conjugate nuclei, the E1 selection rules forbid the decay between states with isospin I=0. The degree of mixing is deduced from statistical-model analysis of the γ-ray spectrum emitted by the compound nucleus 80Zr with the standard parameters deduced from the γ decay of the nucleus 81Rb. The results are used to deduce the zero-temperature value, which is then compared with the latest predictions. The Coulomb spreading width is found to be independent of temperature.

  10. Isospin mixing at finite temperature in 80Zr

    Science.gov (United States)

    Corsi, A.; Bracco, A.; Camera, F.; Crespi, F. C. L.; Giaz, A.; Leoni, S.; Montanari, D.; Nicolini, R.; Vandone, V.; Wieland, O.; Benzoni, G.; Blasi, N.; Brambilla, S.; Million, B.; Kravchuk, V. L.; Cinausero, M.; Degerlier, M.; Gramegna, F.; Marchi, T.; Barlini, S.; Bardelli, L.; Bini, M.; Casini, G.; Nannini, A.; Pasquali, G.; Poggi, G.; Baiocco, G.; Bruno, M.; D'Agostino, M.; Morelli, L.; Vannini, G.; Ciemala, M.; Kmiecik, M.; Maj, A.; Mazurek, K.; Meczynski, W.; Myalski, S.

    2012-09-01

    The degree of isospin mixing in the hot compound nucleus 80Zr has been extracted by statistical-model analysis of the γ-decay spectrum emitted in fusion reactions 40Ca+40Ca at Ebeam = 200 MeV and 37Cl+44Ca at Ebeam = 153 MeV. In the case of 40Ca+40Ca reaction an hindrance of first-step γ-decay is expected because in self-conjugate nuclei the E1 selection rules forbid the decay between states with isospin I=0. The results obtained at finite temperature (T ~ 2 MeV) have been used to extrapolate the degree of mixing at zero temperature

  11. Calcium-41 as a long-term biological tracer for bone resorption

    Science.gov (United States)

    Elmore, David; Bhattacharyya, Maryka H.; Sacco-Gibson, Nancy; Peterson, David P.

    1990-12-01

    The use of 41Ca (half-life 1 × 10 5 yr) as a tracer for studying calcium metabolism in living systems is compared to the shorter-lived radionuclides 45Ca (165 d) and 47Ca (45 d) and the stable isotopes 42Ca and 44Ca. The feasibility of using accelerator mass spectrometry (AMS) measurements of 41Ca for studying multi-year calcium resorption in humans was tested as part of a companion study that used 45Ca to measure the effects of dietary cadmium on calcium metabolism in dogs. It was shown that Ca resorbed from prelabeled bones correlates well with 45Ca for a period of 28 weeks. The advantage of 41Ca is that, even with a negligible radiation dose, it can be measured by AMS long after the 45Ca becomes unmeasurable.

  12. Improved parametrization of the unified model for alpha decay and alpha capture

    CERN Document Server

    Denisov, V Yu; Sedykh, I Yu

    2015-01-01

    The updated data for the ground-state-to-ground-state alpha-transition half-lives in 401 nuclei and the alpha capture cross sections of 40Ca, 44Ca, 59Co, 208Pb and 209Bi are well described in the framework of the unified model for alpha-decay and alpha-capture. The updated values of the alpha decay half-lives, the binding energies of nuclei, the spins of parent and daughter nuclei, and the surface deformation parameters are used for the reevaluation of the model parameters. The data for the ground-state-to-ground-state alpha-decay half-lives are also well described by the empirical relationships.

  13. Experimental identification of mechanisms controlling calcium isotopic fractionations by the vegetation.

    Science.gov (United States)

    Cobert, Florian; Schimtt, Anne-Désirée.; Bourgeade, Pascale; Stille, Peter; Chabaux, François; Badot, Pierre-Marie; Jaegler, Thomas

    2010-05-01

    This study aims to better understand the role of vegetation on the Ca cycle at the level of the critical zone of the Earth, in order to specify the mechanisms controlling the Ca absorption by plants at the rock/plant interface. To do this, we performed experiments using hydroponic plant cultures in a way that we could control the co-occuring geochemical and physiological process and determine the impact of the nutritive solution on the Ca cycle within plants. A dicotyledon and calcicole plant with rapid growth, the French bean (Phaseolus vulgaris L.), has been chosen to have access to one complete growth cycle. Several experiments have been conducted with two Ca concentrations, 6 (L) and 60 (H) ppm and two pH values (4 and 6) in the nutritive solution, for which the Ca concentration was maintained constant, so its Ca content is considered as infinite. A second experiment (non infinite L6) allowed Ca depletion in the solution through time; therefore, response effects on the Ca isotopic signatures in the plant organs and in the nutritive solution were observed. We determined Ca concentrations and isotopic ratios in the nutritive solution and in different organs (main roots, secondary roots, old and young stems, old and young leaves and fruits) at two different growth stages (10 days and 6 weeks). Preliminary results show that: (1) the roots (main and secondary) were enriched in the light isotope (40Ca) compared to the nutritive solution, and leaves were enriched in the heavy isotope (44Ca) compared to stems. These results are in accord with previously published field studies (Wigand et al., 2005; Page et al., 2008; Cenki-Tok et al., 2009; Holmden and Bélanger, 2010). Leaves and secondary roots were however enriched in the heavy isotope (44Ca) compared to bean pods, stems and main roots. These results could be related to kinetic fractionation processes occurring either during the Ca root uptake, or during the Ca transport within the plant, or physiological mechanisms

  14. Promises of cyclotron-produced 44Sc as a diagnostic match for trivalent β--emitters: in vitro and in vivo study of a 44Sc-DOTA-folate conjugate.

    Science.gov (United States)

    Müller, Cristina; Bunka, Maruta; Reber, Josefine; Fischer, Cindy; Zhernosekov, Konstantin; Türler, Andreas; Schibli, Roger

    2013-12-01

    In recent years, implementation of (68)Ga-radiometalated peptides for PET imaging of cancer has attracted the attention of clinicians. Herein, we propose the use of (44)Sc (half-life = 3.97 h, average β(+) energy [Eβ(+)av] = 632 keV) as a valuable alternative to (68)Ga (half-life = 68 min, Eβ(+)av = 830 keV) for imaging and dosimetry before (177)Lu-based radionuclide therapy. The aim of the study was the preclinical evaluation of a folate conjugate labeled with cyclotron-produced (44)Sc and its in vitro and in vivo comparison with the (177)Lu-labeled pendant. (44)Sc was produced via the (44)Ca(p,n)(44)Sc nuclear reaction at a cyclotron (17.6 ± 1.8 MeV, 50 μA, 30 min) using an enriched (44)Ca target (10 mg (44)CaCO3, 97.00%). Separation from the target material was performed by a semiautomated process using extraction chromatography and cation exchange chromatography. Radiolabeling of a DOTA-folate conjugate (cm09) was performed at 95°C within 10 min. The stability of (44)Sc-cm09 was tested in human plasma. (44)Sc-cm09 was investigated in vitro using folate receptor-positive KB tumor cells and in vivo by PET/CT imaging of tumor-bearing mice Under the given irradiation conditions, (44)Sc was obtained in a maximum yield of 350 MBq at high radionuclide purity (>99%). Semiautomated isolation of (44)Sc from (44)Ca targets allowed formulation of up to 300 MBq of (44)Sc in a volume of 200-400 μL of ammonium acetate/HCl solution (1 M, pH 3.5-4.0) within 10 min. Radiolabeling of cm09 was achieved with a radiochemical yield of greater than 96% at a specific activity of 5.2 MBq/nmol. In vitro, (44)Sc-cm09 was stable in human plasma over the whole time of investigation and showed folate receptor-specific binding to KB tumor cells. PET/CT images of mice injected with (44)Sc-cm09 allowed excellent visualization of tumor xenografts. Comparison of cm09 labeled with (44)Sc and (177)Lu revealed almost identical pharmacokinetics. This study presents a high-yield production and

  15. Ca isotopes in the Ebro River Basin: mixing and lithological tracer

    Science.gov (United States)

    Guerrot, C.; Negrel, P. J.; Millot, R.; Petelet-Giraud, E.; Brenot, A.

    2012-12-01

    A large investigation of the Ebro River catchment was done in the past years regarding hydrogen, oxygen, lithium, boron, sulphur and oxygen from SO4 and strontium isotope measurements together with major and trace elements in the dissolved load of 25 river samples collected within the Ebro River Basin in Spain (Millot et al., Geophysical Research Abstracts, Vol. 14, EGU2012-2062, 2012). The Ebro River (928 km long, 85,530 km2 drainage basin) located in North-Eastern Spain rises near the Atlantic coast in the Cantabrian Mountains and flows into the western Mediterranean Sea through several large cities and agricultural, mining and industrial areas. The river is one of the largest contributors of freshwater in the Mediterranean Sea and ends in the Ebro delta, one of the most important wetlands in Europe. Bedrocks of the Ebro River Basin are mainly dominated by carbonates and evaporites from the Paleozoic and Mesozoic terrains. The Ebro river mainstream was sampled at Amposta one time per month between June 2005 and May 2006 and secondly, the Ebro River along its main course and its main tributaries were sampled during one field campaign in April 2006. The behaviour of Ca and its isotopes during water/rock interactions at the scale of a large river basin having various lithologies will be investigated in addition with Sr, S (SO4) and O (SO4) isotopes. One objective is to characterize the processes controlling the isotope signatures of a large river draining predominantly sedimentary bedrocks. The δ44Ca ratio (δ44/40 normalised to Seawater) ranged between -0.87 and -1.09‰ along the Ebro main stream, increasing towards the delta as the Ca content increase. In Amposta, the δ44Ca ratio ranged between -0.66 and -1.04‰ and tends to decrease with the increasing discharge. These variations are very similar to those given by the 87Sr/86Sr ratios and Sr contents. For the tributaries, the δ44Ca ratio ranged between -0.43 and -1.04‰ whereas the anhydrite-gypsum bedrock

  16. Biological fractionation of stable Ca isotopes in Göttingen minipigs as a physiological model for Ca homeostasis in humans.

    Science.gov (United States)

    Heuser, Alexander; Eisenhauer, Anton; Scholz-Ahrens, Katharina E; Schrezenmeir, Jürgen

    2016-12-01

    In order to investigate fractionation of calcium (Ca) isotopes in vertebrates as a diagnostic tool to detect Ca metabolism dysfunction we analyzed the Ca isotopic composition (δ(44/40)Ca = [((44)Ca/(40)Ca)sample/((44)Ca/(40)Ca)reference]-1) of diet, faeces, blood, bones and urine from Göttingen minipigs, an animal model for human physiology. Samples of three groups were investigated: 1. control group (Con), 2. group with glucocorticosteroid induced osteoporosis (GIO) and 3. group with Ca and vitamin D deficiency induced osteomalacia (-CaD). In contrast to Con and GIO whose average δ(44/40)Cafaeces values (0.39 ± 0.13‰ and 0.28 ± 0.08‰, respectively) tend to be lower than their diet (0.47 ± 0.02‰), δ(44/40)Cafaeces of -CaD (-0.27 ± 0.21‰) was significantly lower than their δ(44/40)Cadiet (0.37 ± 0.03‰), but also lower than δ(44/40)Cafaeces of Con and GIO. We suggest that the low δ(44/40)Cafaeces of -CaD might be due to the contribution of isotopically light Ca from gastrointestinal fluids during gut passage. Assuming that this endogenous Ca source is a common physiologic feature, a fractionation during Ca absorption is also required for explaining δ(44/40)Cafaeces of Con and GIO. The δ(44/40)Caurine of all groups are high (>2.0‰) reflecting preferential renal reabsorption of light Ca isotopes. In Göttingen minipigs we found a Ca isotope fractionation between blood and bones (Δ(44/40)Cablood-bone) of 0.68 ± 0.15‰.

  17. A systematic study of actinide production from the interactions of heavy ions with sup 248 Cm

    Energy Technology Data Exchange (ETDEWEB)

    Leyba, J.D.

    1990-09-07

    Production cross sections for heavy actinides produced from the interactions of {sup 12}C, {sup 31}P, {sup 40}Ar, and {sup 44}Ca ions with {sup 248}Cm were measured at energies ranging from 0.98 to 1.35 X Coulomb barrier. The recoiling reaction products were collected in copper or gold catcher foils located near the {sup 248}Cm target. Separate fractions of Bk, Cf, Es, Fm, and Md were obtained from a radiochemical separation procedure. For the {sup 12}C system, a He/KCl jet was used to transport the recoiling No activities of interest to a rotating wheel system. The isotopic distributions of the actinide products were found to be essentially symmetric about the maximum with full-widths-at-half-maximum of approximately 2.5 mass units. Isotopic distributions of the {sup 12}C, {sup 31}P, {sup 40}Ar, and {sup 44}Ca systems were found to be very similar to the {sup 40,48}Ca systems studied previously. The maxima of the isotopic distributions generally occurred for those reaction channels which involved the exchange of the fewest number of nucleons between the target and projectile for which the calculated excitation energy was a positive quantity. Additionally, the maxima of the excitation functions occurred at those projectile energies which were consistent with the calculated reaction barriers based upon a binary reaction mechanism. The experimental data from the four systems investigated were compared to several models of heavy ion interactions including a damped reaction mechanism, compound nucleus formation and subsequent particle evaporation, and classical partial wave calculations for binary systems.

  18. Coupled extremely light Ca and Fe isotopes in peridotites

    Science.gov (United States)

    Zhao, Xinmiao; Zhang, Zhaofeng; Huang, Shichun; Liu, Yufei; Li, Xin; Zhang, Hongfu

    2017-07-01

    Large metal stable isotopic variations have been observed in both extraterrestrial and terrestrial samples. For example, Ca exhibits large mass-dependent isotopic variation in terrestrial igneous rocks and mantle minerals (on the order of ∼2‰ variation in 44Ca/40Ca). A thorough assessment and understanding of such isotopic variations in peridotites provides important constraints on the evolution and compositon of the Earth's mantle. In order to better understand the Ca and Fe isotopic variations in terrestrial silicate rocks, we report Ca isotopic compositions in a set of peridotitic xenoliths from North China Craton (NCC), which have been studied for Fe isotopes. These NCC peridotites have large Ca and Fe isotopic variations, with δ44/40Ca ranging from -0.08 to 0.92 (delta value relative to SRM915a) and δ57/54Fe (delta value relative to IRMM-014) ranging from -0.61 to 0.16, and these isotopic variations are correlated with large Mg# (100 × Mg/(Mg + Fe) molar ratio) variation, ranging from 80 to 90. Importantly, NCC Fe-rich peridotites have the lowest 44Ca/40Ca and 57Fe/54Fe ratios in all terrestrial silicate rocks. In contrast, although ureilites, mantle rocks from a now broken differentiated asteroid(s), have large Mg# variation, from 70 to 92, they have very limited δ57Fe/54Fe variation (0.03-0.21, delta value relative to IRMM-014). Our model calculations show that the coupled extremely light Ca-Fe isotopic signatures in NCC Fe-rich peridotites most likely reflect kinetic isotopic fractionation during melt-peridotite reaction on a timescale of several to 104 years. In addition, our new data and compiled literature data show a possible compositional effect on the inter-mineral Ca isotopic fractionation between co-existing clinopyroxene and orthopyroxene pairs.

  19. Sertindole for schizophrenia.

    Science.gov (United States)

    Lewis, R; Bagnall, A-M; Leitner, M

    2005-07-20

    treatments for patients with schizophrenia or related psychosis . We independently inspected citations and, where possible abstracts; ordered papers for re-inspection and quality assessment and independently extracted data. For homogeneous dichotomous data, we calculated the risk ratio (RR), 95% confidence interval (CI) and, where appropriate, the number needed to treat (NNT) or number needed to harm (NNH) on an intention-to-treat basis. For continuous data, we calculated weighted mean differences (WMD). We inspected all data for heterogeneity. Currently the review includes three studies with a total of 1,104 participants. One was a medium term (eight weeks) placebo controlled study that examined three different doses of sertindole (8, 12 and 20mg/day). The remaining two studies compared the use of sertindole with haloperidol (10mg/day). One was a short term study (six weeks) that looked at four different doses of sertindole (8, 16, 20, 24mg/day) and the other was a long term study (one year) that evaluated the use of sertindole 24mg/day in participants attending outpatients. We excluded two large important studies because they did not report any usable data. (Both had greater than 50% loss to follow-up and data on 'leaving the study early' was inadequately reported). SERTINDOLE VERSUS PLACEBO: Sertindole at 20mg/day was found to be more effective than placebo in terms of BPRS total scores (1 study, n=78, MD 6.2, CI -11.8 to -0.6) and CGI total end point scores (1 study, n=78, MD -0.9, CI -1.6 to -0.2). A marginally statistically significantly greater number of participants that were treated with 20 mg of sertindole were reported to have been 'very much improved' as compared to those taking placebo (1 study, n=102, RR 7.6, CI 1.0 to 57.9, NNT 7.9, CI 4.3 to 41.1). There was no statistically significant difference between sertindole at 8 or 12 mg/day and placebo for these three outcome measures. There were no statistically significant differences between sertindole (8, 12 or

  20. ZIRCONIUM—HAFNIUM ISOTOPE EVIDENCE FROM METEORITES FOR THE DECOUPLED SYNTHESIS OF LIGHT AND HEAVY NEUTRON-RICH NUCLEI

    Energy Technology Data Exchange (ETDEWEB)

    Akram, W.; Schönbächler, M. [School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Sprung, P. [Institut für Planetologie, Universität Münster, Wilhelm-Klemm-Strasse 10, D-48149 Münster (Germany); Vogel, N. [Institute for Geochemistry and Petrology, ETH, Clausiusstrasse 25, 8092 Zürich (Switzerland)

    2013-11-10

    Recent work based on analyses of meteorite and terrestrial whole-rock samples showed that the r- and s- process isotopes of Hf were homogeneously distributed throughout the inner solar system. We report new Hf isotope data for Calcium-Aluminum-rich inclusions (CAIs) of the CV3 carbonaceous chondrite Allende, and novel high-precision Zr isotope data for these CAIs and three carbonaceous chondrites (CM, CO, CK). Our Zr data reveal enrichments in the neutron-rich isotope {sup 96}Zr (≤1ε in {sup 96}Zr/{sup 90}Zr) for bulk chondrites and CAIs (∼2ε). Potential isotope effects due to incomplete sample dissolution, galactic and cosmic ray spallation, and the nuclear field shift are assessed and excluded, leading to the conclusion that the {sup 96}Zr isotope variations are of nucleosynthetic origin. The {sup 96}Zr enrichments are coupled with {sup 50}Ti excesses suggesting that both nuclides were produced in the same astrophysical environment. The same CAIs also exhibit deficits in r-process Hf isotopes, which provides strong evidence for a decoupling between the nucleosynthetic processes that produce the light (A ≤ 130) and heavy (A > 130) neutron-rich isotopes. We propose that the light neutron-capture isotopes largely formed in Type II supernovae (SNeII) with higher mass progenitors than the supernovae that produced the heavy r-process isotopes. In the context of our model, the light isotopes (e.g. {sup 96}Zr) are predominantly synthesized via charged-particle reactions in a high entropy wind environment, in which Hf isotopes are not produced. Collectively, our data indicates that CAIs sampled an excess of materials produced in a normal mass (12-25 M{sub ☉}) SNII.

  1. Method for net decrease of hazardous radioactive nuclear waste materials. [Thermal neutron irradiation of long-lived radionuclides to produce stable nuclides and short-lived radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Marriott, R.; Henyey, F.S.; Hochstim, A.R.

    1988-01-26

    A method of decreasing the amount of relatively long lived fission products in radioactive waste materials in excess of that due to their natural radioactive decay by producing relatively short lived radioactive nuclides and stable nuclides from the relatively long lived fission products is described comprising the steps of: (a) separating the fission products into at least (1) physically separate groups, and (2) relatively short lived fission product radioactive nuclides and stable nuclides; (b) storing the relatively short lived radioactive nuclides and stable nuclides; (c) exposing at least the groups containing Kr/sup 85/, Sr/sup 90/, Zr/sup 93/, Tc/sup 99/, Pd/sup 107/, I/sup 129/, Cs/sup 135/, Sm/sup 151/ + Eu, and actinides, to a high thermal neutron flux for separate, different predetermined periods of time selected in accordance with the long lived fission product nuclide in the corresponding group for inducing predetermined transformations of the relatively long lived fission product nuclides to produce relatively short lived radioactive nuclides and stable nuclides; (d) removing each exposed group containing the produced relatively short lived radioactive nuclides and stable nuclides from the high thermal neutron flux; (e) separating the removed group into (1) the produced short lived radioactive nuclides and stable nuclides, and (2) a plurality of further groups having long lived fission product nuclides respectively corresponding to at least some of the long lived fission product nuclides or the groups of step (a); (f) storing the produced short lived radioactive nuclides and stable nuclides; (g) joining at least one of the further groups to at least one of the groups of step (a) having a corresponding long lived fission product nuclide.

  2. Damping of high-lying single-particle modes in heavy nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Gales, S.; Stoyanov, C.; Vdovin, A.I.

    1988-08-01

    The recent experimental and theoretical results on the damping of high-lying single-particle modes in heavy nuclei are reviewed. In one-nucleon transfer reactions these states manifest themselves as broad 'resonance'-like structures superimposed on a large continuum. The advantages and the limitations of the transfer reaction approach will be presented using the results from neutron and proton pick-up and stripping reactions. The problem raised by the subtraction of the underlying background, the assumptions made to describe the reaction process and the method used to extract the strength distributions are presented. The existing empirical systematics is summarized for nuclei ranging from /sup 90/Zr to /sup 208/Pb. The theoretical approaches used to explain the damping of the high-lying single-particle modes are based on the coupling between collective and single-particle degrees of freedom. In a first step the bare single-particle mode is spread over several doorway collective states due to the interaction with surface vibrations. In a second step the doorway states spread their strengths over many other degrees of freedom. These two steps of the damping mechanism are discussed in detail within the framework of the quasiparticle-phonon nuclear model. A large-scale comparison between the measured and calculated average energies, spreading widths and spectroscopic strengths of the high-lying single-particle (hole) states in heavy nuclei is presented. The systematic features of the damping (energy, angular momentum and isotopic dependence) are discussed. Recent advances of the experimental approaches, such as the ..gamma..-decay of the high-lying states or the use of heavy-ion transfer reactions at intermediate energies, are outlined. The detailed study of the damping mechanism of high-lying single-particle modes reveals new features and leads us to a new field in nuclear structure: 'The spectroscopy of inner and outer subshells'.

  3. Tritium production in a sphere of /sup 6/LiD irradiated by 14-MeV neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Hemmendinger, A.; Ragan, C.E.; Shunk, E.R.; Ellis, A.N.; Anaya, J.M.; Wallace, J.M.

    1978-10-01

    The specific production of tritium in samples of /sup 6/LiH and /sup 7/LiH embedded in a 600-mm-diam sphere of /sup 6/LiD irradiated by a central source of 14-MeV neutrons was determined by measuring the activity of the hydrogen evolved from the samples of each isotope at each of five different radii in the /sup 6/LiD assembly. The entire process of decomposing the LiH, transferring the evolved gas into counters, and determining the decay rate was standardized by processing LiH samples irradiated by thermal neutrons for which the /sup 6/Li(n,..cap alpha..) cross section is well known. The specific production of tritium in /sup 6/LiH and /sup 7/LiH (embedded samples) and the activation of radiochemical detector foils of /sup 45/Sc, /sup 89/Y, /sup 90/Zr, /sup 169/Tm, /sup 191/Ir /sub 373/, /sup 193/Ir /sub 627/, /sup 197/Au, /sup 235/U, and /sup 238/U placed at various positions in the /sup 6/LiD sphere were calculated and compared with the experimental data. One- and three-dimensional Monte Carlo and S/sub n/ neutron-transport calculations were performed. The most reliable (three-dimensional Monte Carlo) calculation is in reasonable agreement with both the tritium-production and the radiochemical-activation data. The existing discrepancies between calculation and experiment appear largely attributable to uncertainties in some tritium-production and radiochemical-activation cross sections. 15 references.

  4. Depth profiling of ZrO{sub 2}/SiO{sub 2}/Si stacks - a TOF-SIMS and computer simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Ignatova, V.A.; Conard, T.; Moeller, W.; Vandervorst, W.; Gijbels, R

    2004-06-15

    This study is dedicated to a better understanding of the processes occurring under ion bombardment of ultra-thin ZrO{sub 2}/SiO{sub 2}/Si gate dielectric stacks. Complex-shaped depth profiles were obtained by using TOF-SIMS with dual beam (500 eV for sputtering and 10 keV for analysis) Ar{sup +} ions. The SIMS intensities of all the elements depend critically on the amount of oxygen at any moment of the sputtering process. Increased intensity is observed at the surface and at the ZrO{sub 2}/SiO{sub 2} interface. A long tail of the Zr signal is present in the Si substrate, even after the second (SiO{sub 2}/Si) interface, and a double bump structure in the {sup 90}Zr and ZrO dimer is observed, which is more pronounced with increasing thickness of the interfacial SiO{sub 2} layer. Computer simulations using the dynamic Monte Carlo code (TRIDYN) are performed in order to distinguish the ion-bombardment-induced effects from changes in the ionization degree. The original code is extended with simple models for the ionization mechanism and for the molecular yield during sputtering. Oxygen preferential sputtering at the surface and ballistic transport of Zr towards and through the interface are clearly demonstrated, but there is also evidence that due to recoil implantation oxygen gets piled-up near the ZrO{sub 2}/SiO{sub 2} interface.

  5. Microscopic description of elastic and direct inelastic nucleon scattering off spherical nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Dupuis, M. [CEA, DAM, DIF, Arpajon (France)

    2017-05-15

    The purpose of this study is to improve the modeling of nucleon direct inelastic scattering to the continuum using a microscopic and parameter-free approach. For the first time, direct elastic scattering, inelastic scattering to discrete excitations and to the continuum are described within a microscopic approach without adjustable parameters. Proton scattering off {sup 90}Zr and {sup 208}Pb are the reactions used as test case examples of the calculations. The model uses the Melbourne g-matrix and the Random Phase Approximation description of nuclear states, implemented with the Gogny D1S interaction. The relevant optical and transition potentials in a finite nucleus are calculated within a local density approximation. As we use the nuclear matter approach we limit our study to incident energies above 40 MeV. We first checked that this model provides an accurate account of measured cross sections for elastic scattering and inelastic scattering to discrete states. It is then applied to the direct inelastic scattering to the continuum considering all one-phonon excitations predicted within the RPA approach. This accounts for a part of the direct pre-equilibrium emission, often labeled as the one-step direct process in quantum-based approaches. Our approach provides a very accurate description of angular distributions where the one-step process dominates. The impact of collective excitations is shown to be non negligible for energy transfer to the target up to 20 MeV, decreasing as the incident energy increases. For incident energies above 80 MeV, our modeling provides a good account of direct proton emission for an energy transfer to the target up to 30 MeV. However, the proton emission we predict underestimates the measured cross sections for incident energies below 80 MeV. We compare our prediction to those of the phenomenological exciton model to help interpret this result. Directions that may improve our modeling are discussed. (orig.)

  6. Cross Sections Calculations of ( d, t) Nuclear Reactions up to 50 MeV

    Science.gov (United States)

    Tel, E.; Yiğit, M.; Tanır, G.

    2013-04-01

    In nuclear fusion reactions two light atomic nuclei fuse together to form a heavier nucleus. Fusion power is the power generated by nuclear fusion processes. In contrast with fission power, the fusion reaction processes does not produce radioactive nuclides. The fusion will not produce CO2 or SO2. So the fusion energy will not contribute to environmental problems such as particulate pollution and excessive CO2 in the atmosphere. Fusion powered electricity generation was initially believed to be readily achievable, as fission power had been. However, the extreme requirements for continuous reactions and plasma containment led to projections being extended by several decades. In 2010, more than 60 years after the first attempts, commercial power production is still believed to be unlikely before 2050. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. In the fusion reactor, tritium self-sufficiency must be maintained for a commercial power plant. Therefore, for self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of ( d, t) nuclear reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at different energies. Since the experimental data of charged particle induced reactions are scarce, self-consistent calculation and analyses using nuclear theoretical models are very important. In this study, ( d, t) cross sections for target nuclei 19F, 50Cr, 54Fe, 58Ni, 75As, 89Y, 90Zr, 107Ag, 127I, 197Au and 238U have been investigated up to 50 MeV deuteron energy. The excitation functions for ( d, t) reactions have been calculated by pre-equilibrium reaction mechanism. Calculation results have been also compared with the available measurements in

  7. Symmetry energy III: Isovector skins

    Science.gov (United States)

    Danielewicz, Paweł; Singh, Pardeep; Lee, Jenny

    2017-02-01

    Isoscalar density is a sum of neutron and proton densities and isovector is a normalized difference. Here, we report the experimental evidence for the displacement of the isovector and isoscalar surfaces in nuclei, by ∼ 0.9 fm from each other. We analyze data on quasielastic (QE) charge exchange (p,n) reactions, concurrently with proton and neutron elastic scattering data for the same target nuclei, following the concepts of the isoscalar and isovector potentials combined into Lane optical potential. The elastic data largely probe the geometry of the isoscalar potential and the (p,n) data largely probe a relation between the geometries of the isovector and isoscalar potentials. The targets include 48Ca, 90Zr, 120Sn and 208Pb and projectile incident energy values span the range of (10-50) MeV. In our fit to elastic and QE charge-exchange data, we allow the values of isoscalar and isovector radii, diffusivities and overall potential normalizations to float away from those in the popular Koning and Delaroche parametrization. We find that the best-fit isovector radii are consistently larger than isoscalar and the best-fit isovector surfaces are steeper. Upon identifying the displacement of the potential surfaces with the displacement of the surfaces for the densities in the Skyrme-Hartree-Fock calculations, and by supplementing the results with those from analyzing excitation energies to isobaric analog states in the past, we arrive at the slope and value of the symmetry energy at normal density of 70 < L < 101 MeV and 33.5 < aaV < 36.4 MeV, respectively.

  8. Formation and geochemical significance of micrometallic aggregates including fissiogenic platinum group elements in the Oklo natural reactor, Gabon

    Science.gov (United States)

    Kikuchi, Makiko; Hidaka, Hiroshi; Gauthier-Lafaye, François

    2010-08-01

    Metallic aggregates with a size of a few tens μm and consisting mainly of Ru, Rh, Pd, Te, Pb, As, Sb, S and Bi were found in the acid residue of SD37-S2/CD uraninite taken from Oklo natural reactor zone (RZ) 13. Quantitative analyses of major elements using an electron probe microanalyzer and in situ isotopic analyses of Zr, Mo, Ru, Pb and U using a sensitive high-resolution ion microprobe were performed on the metallic aggregates to determine the geochemical behaviors of fission products and actinides and to ascertain the processes of formation of the aggregates in the RZs. The chemical compositions of the aggregates investigated in this study are significantly different from those reported previously, showing lower Pb content and no correlation between the contents of Pb and S in the individual grains. The 235U/ 238U ratios in metallic aggregates vary significantly from 0.00478 to 0.01466, indicating chemical fractionation between U and Pu during the formation of the aggregates. The Pb isotopic data indicate that most of the Pb in the aggregates decayed from 2.05 Ga-old uraninite that existed in the RZ originally and that there was chemical fractionation between U and Pb in some aggregates. The Zr and Mo isotopic ratios, 90Zr/ 91Zr and 95Mo/ 97Mo, for most of the aggregates had small variations, which can be simply explained by constant separate mixing of fissiogenic and nonfissiogenic components. On the other hand, a large variation in the 99Ru/ 101Ru ratio (0.324-1.73) cannot be explained only by a two component mixing theory; thus, chemical fractionation between Tc and Ru during the reactor criticality is suggested. The large variations in the 235U/ 238U and 99Ru/ 101Ru isotopic ratios suggest that the aggregates formed under various redox conditions owing to the radiolysis of water.

  9. Status of semi-classical distorted wave (SCDW) model

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Y.; Higashi, H.; Kuwata, R.; Kawai, M. [Kyushu Univ., Fukuoka (Japan); Kohno, M.

    1997-05-01

    The SCDW model to describe the preequilibrium MSD reaction was extended so as to include the 3-step process. The MSD calculations of {sup 58}Ni(p,p`x) at energies of 65, 120 and 200 MeV and {sup 90}Zr(p,p`x) at 160 MeV were carried out using the extended SCDW model and compared with the experimental data. The calculations with no free parameter showed overall good agreement with the experiment, although underprediction is seen at very small and backward angles. We found that the 2- and 3-step contributions were not so large enough to compensate the difference between the 1-step cross sections and the experimental ones at backward angles. The discrepancies seen at very small and large angles is possibly responsible for the local Fermi-gas model which does not work well in the nuclear surface region. The comparisons of the SCDW calculations with the AMD, QMD and FKK calculations led to an interesting result that the differences in the shape of 1-step angular distributions are remarkable among the models, but the multistep components are rather similar in the shape of angular distributions and the step-wise contribution is not so much different. The in-medium N-N cross sections were calculated in the nonrelativistic Brueckner framework with the Paris potential, and were parametrized as a function of the incident energy and the nuclear density. The SCDW calculation with the in-medium N-N cross sections was not so different from that with the free ones. (J.P.N.)

  10. A design study for the analysis of 90Sr And 135,137Cs by ISA-AMS

    Science.gov (United States)

    Alary, Jean-François; Cousins, Lisa M.; Eliades, John; Hao, Changtong; Javahery, Gholamreza; Kieser, William E.; Litherland, Albert E.; Zhao, Xiaolei

    2013-04-01

    Extending the range of Accelerator Mass Spectrometry (AMS) to the fission products 90Sr and 135,137Cs would offer numerous advantages for non-proliferation surveillance activities. A new method for suppressing the interfering isobars 90Zr (and 90Y) and 135,137Ba using low kinetic energy (Anions (ISA). Combined with fluoridematrix assisted ionization, this method greatly improves the analytical capabilities of AMS for 90Sr and will enable the direct analysis of 135,137Cs below sub-parts per trillion levels. The ISA alone provides interference suppression factors of 4×10-6 for ZrF3-/SrF3- and 2×10-5 for BaF2-/CsF2-. The general performance improvement provided by the ISA, however, critically depends on the capacity of this device to transmit the wanted anions with a high efficiency and with a stable response to the natural variations of AMS targets. Based on recent SIMION-8.1 studies and on results of a parallel study on the attenuation of other anions, we have developed a pre-commercial design for the ISA. In this design, RFQ rods and split-flow turbo molecular pumps are configured to achieve full control of reaction time, ion energy and fragmentation pathways (chemical and kinetic reactions), and to improve beam transmission through the cell. The mechanical layout will be presented in 3D models using Solid Works; SIMION-8.1 simulations were used to illustrate the importance of optical matching of the RFQ and the front-end DC retardation section of the ISA.

  11. Optimization of collision/reaction gases for determination of 90Sr in atmospheric particulate matter by inductively coupled plasma tandem mass spectrometry after direct introduction of air via a gas-exchange device

    Science.gov (United States)

    Suzuki, Yoshinari; Ohara, Ryota; Matsunaga, Kirara

    2017-09-01

    Nuclear power plant accidents release radioactive strontium 90 (90Sr) into the environment. Monitoring of 90Sr, although important, is difficult and time consuming because it emits only beta radiation. We have developed a new analytical system that enables real-time analysis of 90Sr in atmospheric particulate matter with an analytical run time of only 10 min. Briefly, after passage of an air sample through an impactor, a small fraction of the sample is introduced into a gas-exchange device, where the air is replaced by Ar. Then the sample is directly introduced into an inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) system equipped with a collision/reaction cell to eliminate isobaric interferences on 90Sr from 90Zr+, 89Y1H+, and 90Y+. Experiments with various reaction gas conditions revealed that these interferences could be minimized under the following optimized conditions: 1.0 mL min- 1 O2, 10.0 mL min- 1 H2, and 1.0 mL min- 1 NH3. The estimated background equivalent concentration and estimated detection limit of the system were 9.7 × 10- 4 and 3.6 × 10- 4 ng m- 3, respectively, which are equivalent to 4.9 × 10- 6 and 1.8 × 10- 6 Bq cm- 3. Recoveries of Sr in PM2.5 measured by real-time analysis compared to those obtained by simultaneously collection on filter was 53 ± 23%, and using this recovery, the detection limit as PM2.5 was estimated to be 3.4 ± 1.5 × 10- 6 Bq cm- 3. That is, this system enabled detection of 90Sr at concentrations < 5 × 10- 6 Bq cm- 3 even considering the insufficient fusion/vaporization/ionization efficiency of Sr in PM2.5.

  12. Comparative study of Monte Carlo particle transport code PHITS and nuclear data processing code NJOY for recoil cross section spectra under neutron irradiation

    Science.gov (United States)

    Iwamoto, Yosuke; Ogawa, Tatsuhiko

    2017-04-01

    Because primary knock-on atoms (PKAs) create point defects and clusters in materials that are irradiated with neutrons, it is important to validate the calculations of recoil cross section spectra that are used to estimate radiation damage in materials. Here, the recoil cross section spectra of fission- and fusion-relevant materials were calculated using the Event Generator Mode (EGM) of the Particle and Heavy Ion Transport code System (PHITS) and also using the data processing code NJOY2012 with the nuclear data libraries TENDL2015, ENDF/BVII.1, and JEFF3.2. The heating number, which is the integral of the recoil cross section spectra, was also calculated using PHITS-EGM and compared with data extracted from the ACE files of TENDL2015, ENDF/BVII.1, and JENDL4.0. In general, only a small difference was found between the PKA spectra of PHITS + TENDL2015 and NJOY + TENDL2015. From analyzing the recoil cross section spectra extracted from the nuclear data libraries using NJOY2012, we found that the recoil cross section spectra were incorrect for 72Ge, 75As, 89Y, and 109Ag in the ENDF/B-VII.1 library, and for 90Zr and 55Mn in the JEFF3.2 library. From analyzing the heating number, we found that the data extracted from the ACE file of TENDL2015 for all nuclides were problematic in the neutron capture region because of incorrect data regarding the emitted gamma energy. However, PHITS + TENDL2015 can calculate PKA spectra and heating numbers correctly.

  13. Comparative study of Monte Carlo particle transport code PHITS and nuclear data processing code NJOY for recoil cross section spectra under neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, Yosuke, E-mail: iwamoto.yosuke@jaea.go.jp; Ogawa, Tatsuhiko

    2017-04-01

    Because primary knock-on atoms (PKAs) create point defects and clusters in materials that are irradiated with neutrons, it is important to validate the calculations of recoil cross section spectra that are used to estimate radiation damage in materials. Here, the recoil cross section spectra of fission- and fusion-relevant materials were calculated using the Event Generator Mode (EGM) of the Particle and Heavy Ion Transport code System (PHITS) and also using the data processing code NJOY2012 with the nuclear data libraries TENDL2015, ENDF/BVII.1, and JEFF3.2. The heating number, which is the integral of the recoil cross section spectra, was also calculated using PHITS-EGM and compared with data extracted from the ACE files of TENDL2015, ENDF/BVII.1, and JENDL4.0. In general, only a small difference was found between the PKA spectra of PHITS + TENDL2015 and NJOY + TENDL2015. From analyzing the recoil cross section spectra extracted from the nuclear data libraries using NJOY2012, we found that the recoil cross section spectra were incorrect for {sup 72}Ge, {sup 75}As, {sup 89}Y, and {sup 109}Ag in the ENDF/B-VII.1 library, and for {sup 90}Zr and {sup 55}Mn in the JEFF3.2 library. From analyzing the heating number, we found that the data extracted from the ACE file of TENDL2015 for all nuclides were problematic in the neutron capture region because of incorrect data regarding the emitted gamma energy. However, PHITS + TENDL2015 can calculate PKA spectra and heating numbers correctly.

  14. Structural and crystallisation study of a rare earth alumino borosilicate glass designed for nuclear waste confinement; Etude de la structure et du comportement en cristallisation d'un verre nucleaire d'aluminoborosilicate de terre rare

    Energy Technology Data Exchange (ETDEWEB)

    Quintas, A

    2007-09-15

    This work is devoted to the study of a rare earth alumino borosilicate glass, which molar composition is 61,81 SiO{sub 2} - 3,05 Al{sub 2}O{sub 3} - 8,94 B{sub 2}O{sub 3} - 14,41 Na{sub 2}O - 6,33 CaO - 1,90 ZrO{sub 2} - 3,56 Nd{sub 2}O{sub 3}, and envisaged for the immobilization of nuclear wastes originating from the reprocessing of high discharge burn up spent fuel. From a structural viewpoint, we investigated the role of the modifier cations on the arrangement of the glass network through different modifications of the glass composition: variation of the Na/Ca ratio and modification of the nature of the alkali and alkaline earth cations. The NMR and Raman spectroscopic techniques were useful to determine the distribution of modifier cations among the glass network and also to cast light on the competition phenomena occurring between alkali and alkaline earth cations for charge compensation of [AlO{sub 4}]{sup -} and [BO{sub 4}]{sup -} species. The neodymium local environment could be probed by optical absorption and EXAFS spectroscopies which enabled to better understand the insertion mode of Nd{sup 3+} ions among the silicate domains of the glass network. Concerning the crystallization behavior we were interested in how the glass composition may influence the crystallization processes and especially the formation of the apatite phase of composition Ca{sub 2}Nd{sub 8}(SiO{sub 4}){sub 6}O{sub 2}. In particular, this work underlined the important role of both alkaline earth and rare earth cations on the crystallization of the apatite phase. (author)

  15. Use of Organic Compost Containing Waste from Small Ruminants in Corn Production

    Directory of Open Access Journals (Sweden)

    Henrique Antunes de Souza

    Full Text Available ABSTRACT Composting is a useful way of transforming livestock waste into organic fertilizer, which is proven to increase soil nutrient levels, and thus crop yield. Remains from production and slaughter of small ruminants can become a source of important elements for plant growth, such as N, after microorganism-driven decomposition.The aim of this investigation was to evaluate the effects of this compost on soil fertility and on the nutritional status and yield of the corn crop. The experiment was conducted in a Haplic Luvisol in a randomized block design with six treatments and five application rates of the organic compound in Mg ha-1: 3 (half the standard rate, 6 (standard rate, 9 (one and a half times the standard rate, 12 (twice the standard rate, and 24 (four times the standard rate and an additional treatment with mineral fertilizers (110, 50 e 30 kg ha-1 of N, P2O5 and K2O, respectively, with four blocks. Evaluations were performed for two harvests of rainfed crops, measuring soil fertility, nutritional status, and grain yield. The compost increased P, K, Na and Zn values in the 0.00-0.20 m layer in relation of mineral fertilization in 616, 21, 114 and 90 % with rate 24 Mg ha-1 in second crop. Leaf N, Mg, and S contents, relative chlorophyll content, and the productivity of corn kernels increased in 27, 32, 36, 20 e 85 %, respectively, of low rate (3 Mg ha-1 to high rate (24 Mg ha-1 with of application of the compost. Corn yield was higher with application of organic compost in rate of 24 Mg ha-1 than mineral fertilizer combination in second crop.

  16. Baclofen effects on alcohol seeking, self-administration and extinction of seeking responses in a within-session design in baboons.

    Science.gov (United States)

    Duke, Angela N; Kaminski, Barbara J; Weerts, Elise M

    2014-01-01

    Baclofen, a gamma-aminobutyric acidB receptor agonist, is currently under investigation as a potential treatment to prevent relapse to drinking in alcohol-dependent persons. In the current study, two groups of baboons were trained under a chained schedule of reinforcement (CSR), with three linked components, which were each correlated with different response requirements and cues. Fulfilling the requirement in the second link initiated the third link where either alcohol (n = 4) or a preferred non-alcoholic beverage (Tang, n = 5) was available for self-administration; failure to complete the response requirement in Link 2 ended the session (no access to alcohol or Tang). Seeking responses in Link 2 were used as indices of the motivational processes thought to be involved in relapse. The effects of baclofen (0.1-2.4 mg/kg) were examined under conditions with alcohol or Tang access and under extinction. Under the CSR, baclofen (1.8 and 2.4 mg/kg) significantly decreased (P baclofen (2.4 mg/kg) reduced Tang self-administration and consumption. Under within-session extinction conditions, baclofen (1.8 and 2.4 mg/kg) facilitated extinction of responding for both alcohol and Tang, particularly during the first 10 minutes of extinction. Baclofen may be effective in reducing craving and alcohol drinking, although the facilitation of extinction and suppression of both alcohol and Tang self-administration by baclofen suggests these effects may be related to a more general suppression of consummatory and conditioned behaviors.

  17. Effects of Dihydroartemisinin and Artemether on the Growth, Chlorophyll Fluorescence, and Extracellular Alkaline Phosphatase Activity of the Cyanobacterium Microcystis aeruginosa

    Science.gov (United States)

    Wang, Shoubing; Xu, Ziran

    2016-01-01

    Increased eutrophication in the recent years has resulted in considerable research focus on identification of methods for preventing cyanobacterial blooms that are rapid and efficient. The objectives of this study were to investigate the effects of dihydroartemisinin and artemether on the growth of Microcystis aeruginosa and to elucidate its mode of action. Variations in cell density, chlorophyll a, soluble protein, malondialdehyde, extracellular alkaline phosphatase activity (APA), and chlorophyll fluorescence parameters (Fv/Fm, ΦPSII, ETR, rapid light curves, fast chlorophyll fluorescence curves on fluorescence intensity, and relative variable fluorescence) were evaluated by lab-cultured experiments. Our results demonstrated that both dihydroartemisinin and artemether inhibited the growth of M.aeruginosa by impairing the photosynthetic center in photosystem II and reducing extracellular APA, with a higher sensitivity exhibited toward artemether. The inhibitory effects of dihydroartemisinin on M.aeruginosa increased with concentration, and the maximum growth inhibitory rate was 42.17% at 24 mg·L-1 after 120h exposure, whereas it was 55.72% at 6 mg·L-1 artemetherafter 120h exposure. Moreover, the chlorophyll fluorescence was significantly inhibited (p<0.05) after 120h exposure to 12 and 24 mg·L-1 dihydroartemisinin. Furthermore, after 120h exposure to 6 mg·L-1 artemether, Fv/Fm, ΦPSII, ETR and rETRmax showed a significant decrease (p<0.01) from initial values of 0.490, 0.516, 17.333, and 104.800, respectively, to 0. One-way analysis of variance showed that 6 mg·L-1 artemether and 24 mg·L-1 dihydroartemisinin had significant inhibitory effects on extracellular APA (p<0.01). The results of this study would be useful to further studies to validate the feasibility of dihydroartemisinin and artemether treatment to inhibit overall cyanobacterial growth in water bodies, before this can be put into practice. PMID:27755566

  18. Unusual Isospin-Breaking and Isospin-Mixing Effects in the A=35 Mirror Nuclei

    Science.gov (United States)

    Ekman, J.; Rudolph, D.; Fahlander, C.; Zuker, A. P.; Bentley, M. A.; Lenzi, S. M.; Andreoiu, C.; Axiotis, M.; de Angelis, G.; Farnea, E.; Gadea, A.; Kröll, Th.; Mărginean, N.; Martinez, T.; Mineva, M. N.; Rossi-Alvarez, C.; Ur, C. A.

    2004-04-01

    Excited states have been studied in 35Ar following the 16O(24Mg,1α1n)35Ar fusion-evaporation reaction at 60MeV using the Ge-detector array GASP. A comparison with the mirror nucleus 35Cl shows two remarkable features: (i)A surprisingly large energy difference for the 13/2- states, in which the hitherto overlooked electromagnetic spin-orbit term is shown to play a major role, and (ii)a very different decay pattern for the 7/2- states, which provides direct evidence of isospin mixing.

  19. The Hoyle state in Nuclear Lattice EFT

    CERN Document Server

    Lähde, Timo A; Krebs, Hermann; Lee, Dean; Meißner, Ulf-G; Rupak, Gautam

    2014-01-01

    We review the calculation of the Hoyle state of $^{12}$C in Nuclear Lattice Effective Field Theory (NLEFT) and its anthropic implications for the nucleosynthesis of $^{12}$C and $^{16}$O in red giant stars. We also review the extension of NLEFT to the regime of medium-mass nuclei, with emphasis on the determination of the ground-state energies of the alpha nuclei $^{16}$O, $^{20}$Ne, $^{24}$Mg and $^{28}$Si by means of Euclidean time projection. Finally, we review recent NLEFT results for the spectrum, electromagnetic properties, and alpha-cluster structure of $^{16}$O.

  20. Role of deformation on giant resonances within the QRPA approach and the Gogny force

    CERN Document Server

    Peru, S

    2008-01-01

    Fully consistent axially-symmetric-deformed Quasi-particle Random Phase Approximation (QRPA) calculations have been performed, in which the same Gogny D1S effective force has been used for both the Hartree-Fock-Bogolyubov mean field and the QRPA approaches. Giant resonances calculated in deformed $^{26-28}$Si and $^{22-24}$Mg nuclei as well as in the spherical $^{30}$Si and $^{28}$Mg isotopes are presented. Theoretical results for isovector-dipole and isoscalar monopole, quadrupole, and octupole responses are presented and the impact of the intrinsic nuclear deformation is discussed.

  1. Improvement of the ethanol productivity in a high gravity brewing at pilot plant scale.

    Science.gov (United States)

    Dragone, Giuliano; Silva, Daniel P; de Almeida e Silva, João Batista; de Almeida Lima, Urgel

    2003-07-01

    A 23 full factorial design was used to study the influence of different experimental variables, namely wort gravity, fermentation temperature and nutrient supplementation, on ethanol productivity from high gravity wort fermentation by Saccharomyces cerevisiae (lager strain), under pilot plant conditions. The highest ethanol productivity (0.69 g l(-1) h(-1)) was obtained at 20 degrees P [degrees P is the weight of extract (sugar) equivalent to the weight of sucrose in a 100 g solution at 20 degrees C], 15 degrees C, with the addition of 0.8% (w/v) yeast extract, 24 mg l(-1) ergosterol and 0.24% (v/v) Tween 80.

  2. Comportamento ingestivo de novilhas Nelore em pastejo recebendo suplemento a base de própolis ou monensina sódica

    OpenAIRE

    2014-01-01

    We evaluated the effect of additives the basis of propolis and monensin on ingestive behavior (grazing – GRA, rumination lying – RLY, rumination in foot – RFO, rumination – RUM; idleness lying – ILY, idleness in standing – IDS, idleness – IDL, walking – WAL, posture standing – POS, posture lying – PLY, intake of supplement and water – ISW) of heifers in Tifton 85 grazing. The treatments were: no additive (NAD); propolis – PRO (33.24 mg animal-1 of total flavonoid in apigenin), and monensin – ...

  3. The Hoyle state in nuclear lattice effective field theory

    Indian Academy of Sciences (India)

    Timo A Lähde; Evgeny Epelbaum; Hermann Krebs; Dean Lee; Ulf-G Meißner; Gautam Rupak

    2014-11-01

    We review the calculation of the Hoyle state of 12C in nuclear lattice effective field theory (NLEFT) and its anthropic implications in the nucleosynthesis of 12C and 16O in red giant stars. We also analyse the extension of NLEFT to the regime of medium-mass nuclei, with emphasis on the determination of the ground-state energies of the nuclei 16O, 20Ne, 24Mg, and 28Si by Euclidean time projection. Finally, we discuss recent NLEFT results for the spectrum, electromagnetic properties, and α-cluster structure of 16O.

  4. Multifragmentation and dynamics in heavy ion collisions

    Indian Academy of Sciences (India)

    R Roy

    2001-07-01

    A midrapidity zone formed in heavy-ion collisions has been investigated through special selections of light particles and intermediate mass fragments detected in the reaction 35Cl on 12C at 43 MeV/nucleon and the reactions 58Ni on 12C, 24Mg, and 197Au at 34.5 MeV/nucleon, and of neutron energy spectra measured in the reaction 35Cl on natTa. Properties of the observables have been examined to characterize the neck-like structure formed between the two reaction partners.

  5. High-spin states and lifetimes in 33S and shell-model interpretation in the s d -f p space

    Science.gov (United States)

    Aydin, S.; Ionescu-Bujor, M.; Gavrilov, G. Tz.; Dimitrov, B. I.; Lenzi, S. M.; Recchia, F.; Tonev, D.; Bouhelal, M.; Kavillioglu, F.; Pavlov, P.; Bazzacco, D.; Bizzeti, P. G.; Bizzeti-Sona, A. M.; de Angelis, G.; Deloncle, I.; Farnea, E.; Gadea, A.; Gottardo, A.; Goutev, N.; Haas, F.; Huyuk, T.; Laftchiev, H.; Lunardi, S.; Marinov, Tz. K.; Mengoni, D.; Menegazzo, R.; Michelagnoli, C.; Napoli, D. R.; Petkov, P.; Sahin, E.; Singh, P. P.; Stefanova, E. A.; Ur, C. A.; Valiente-Dobón, J. J.; Yavahchova, M. S.

    2017-08-01

    The structure of the 33S nucleus was investigated in the 24Mg(14N,α p ) fusion-evaporation reaction using a 40-MeV 14N beam. The level scheme was extended up to an excitation energy of 11.7 MeV and spin 19 /2+ . Lifetimes of the intermediate- and high-spin states have been investigated by the Doppler shift attenuation method. Data were compared with different shell-model calculations where effective interactions involving two main shells, the sd and the fp, are used.

  6. Differential growth response of Ulva lactuca to ammonium and nitrate assimilation

    DEFF Research Database (Denmark)

    Ale, Marcel Tutor; Mikkelsen, Jørn Dalgaard; Meyer, Anne S

    2011-01-01

    as the nitrogen source. The NH4Cl and NaNO3 rich media (50 μM of N) accelerated U. lactuca growth to a maximum specific growth rate of 16.4 ± 0.18% day−1 and 9.4 ± 0.72% day−1, respectively. The highest biomass production rate obtained was 22.5 ± 0.24 mg DW m−2·day−1. The presence of ammonium apparently...

  7. Alginate and Chitosan Gel Nanoparticles for Efficient Protein Entrapment

    Science.gov (United States)

    Masalova, O.; Kulikouskaya, V.; Shutava, T.; Agabekov, V.

    Alginate and chitosan nanoparticles were synthesized by ionic gelation of the polymers in the presence of stabilizers (PEG 1500, PEG 6000, TWEEN 80). The stability of 210-240 nm Ca-alginate colloids is affected by nanoparticles ageing and by the presence of a stabilizer. The diameter of chitosan nanoparticles is in the range of 180 to 260 nm and depends on polymer concentration in the reaction mixture, its molecular weight, and stabilizer type. The nanoparticles efficiently entrap a model protein, bovine serum albumin, in the amount up to 0.24 mg per 1 mg of polysaccharide.

  8. Efficient Fiber Optic Detection of Trapped Ion Fluorescence

    CERN Document Server

    VanDevender, A P; Amini, J; Leibfried, D; Wineland, D J

    2010-01-01

    Integration of fiber optics may play a critical role in the development of quantum information processors based on trapped ions and atoms by enabling scalable collection and delivery of light and coupling trapped ions to optical microcavities. We trap 24Mg+ ions in a surface-electrode Paul trap that includes an integrated optical fiber for detecting 280-nm fluorescence photons. The collection numerical aperture is 0.37 and total collection efficiency is 2.1 %. The ion can be positioned between 80 \\mum and 100 \\mum from the tip of the fiber by use of an adjustable rf-pseudopotential.

  9. Analytic extension of the nuclear algebraic potential

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenthaeler, R. (Departamento de Fisica Nuclear, Laboratorio do Pelletron, Universidade de Sao Paulo, Caixa Postal 20516, 01452-990 Sao Paulo, Sao Paulo (Brazil)); Gomes, L.C. (Grupo de Fisica Nuclear Teorica e Fenomenologia de Particulas Elementares Instituto de Fisica Universidade de Sao Paulo, Caixa Postal 20516, 01498-970 Sao Paulo, Sao Paulo (Brazil))

    1994-12-01

    An analytic extension of the nuclear algebraic potential in the complex energy and angular momentum planes is discussed and an approximation for the algebraic potential in agreement with the known analytic properties of the [ital S]-matrix is proposed. The invariance of the energy spectrum of the Coulomb part of the interaction is established. The results are applied to the Regge pole analysis of the [sup 12]C+[sup 24]Mg elastic collision at [ital E][sub [ital l][ital a][ital b

  10. Prevalence of alcohol and cannabis use and reported knowledge, attitudes and practice regarding its relationship with health and safety on mines in South Africa

    CSIR Research Space (South Africa)

    Pick, W

    2003-07-01

    Full Text Available possession, and after involvement in work related accidents. A breathalyser result of 0.24 mg/1000ml of breath is regarded as the limit for breath alcohol results at this mine. Though the right of an individual to refuse testing is acknowledged, a....e. normal blood alcohol level). Breath alcohol levels were automatically stored in the instrument, and actual results were downloaded onto a computer and read off after the interviews. 2.4.3 Urine cannabis testing Initial testing for Tetra...

  11. Mercury emission from crematoria.

    Science.gov (United States)

    Santarsiero, Anna; Settimo, Gaetano; Dell'andrea, Elena

    2006-01-01

    The purpose of this study, undertaken at a cremator representing an example of current equipment and cremation practices in use in Italy, is to assess the possible mercury emitted during cremation and substantiate the current data available. This paper reports some preliminary results concerning mercury and total particulate matter emissions during three cremation processes. The obtained results gave a mercury concentration ranging from 0.005 to 0.300 mg/m3 and a mercury emission factor ranging from 0.036 to 2.140 g/corpse cremated. The total particulate matter concentration range was 1.0 to 2.4 mg/m3.

  12. Ameliorative Effect of Ocimum Sanctum on Meloxicam Induced Toxicity in Wistar Rats

    OpenAIRE

    Mahaprabhu, R.; Bhandarkar, A. G.; Jangir, Babu Lal; Rahangadale, S. P.; Kurkure, N. V.

    2011-01-01

    An ameliorating effect of Ocimum sanctum on the toxic effect of meloxicam, a new non-steroidal anti-inflammatory drug was studied by evaluating haemato-biochemical parameters, oxidative stress, gross and histopathological changes in various organs of Wistar rats. A total of thirty-six male rats were divided in six experimental groups each comprising of six rats and numbered from G1 to G6. Meloxicam toxicity was induced by oral feeding of meloxicam at 1.2 mg/kg and 2.4 mg/kg body weight in G2 ...

  13. The use of a short-acting benzodiazepine to reduce the risk of syncopal episodes during upright stereotactic breast biopsy

    Energy Technology Data Exchange (ETDEWEB)

    James, J.J. [Breast Institute, Nottingham City Hospital, Hucknall Road, Nottingham NG5 1PB (United Kingdom)]. E-mail: jjames3@ncht.trent.nhs.uk; Wilson, A.R.M. [Breast Institute, Nottingham City Hospital, Hucknall Road, Nottingham NG5 1PB (United Kingdom); Evans, A.J. [Breast Institute, Nottingham City Hospital, Hucknall Road, Nottingham NG5 1PB (United Kingdom); Burrell, H. [Breast Institute, Nottingham City Hospital, Hucknall Road, Nottingham NG5 1PB (United Kingdom); Cornford, E.J. [Breast Institute, Nottingham City Hospital, Hucknall Road, Nottingham NG5 1PB (United Kingdom); Hamilton, L.J. [Breast Institute, Nottingham City Hospital, Hucknall Road, Nottingham NG5 1PB (United Kingdom)

    2005-03-01

    The use of sublingual lorazepam provides a safe and effective means of reducing the risk of syncopal episodes during upright stereotactic breast biopsy. Sublingual lorazepam, 2-4 mg, was received by 19 women undergoing a total of 20 stereotactic procedures. Of 14 women who had previously fainted during upright stereotactic biopsy, 13 had a successful repeat biopsy following administration of sublingual lorazepam. All 4 women who received lorazepam for significant anxiety had successful biopsies. Stereotactic guided wire localization also was performed in 2 cases.

  14. 2-(4-carbonylphenyl)benzoxazole inhibitors of CETP: scaffold design and advancement in HDLc-raising efficacy.

    Science.gov (United States)

    Sweis, Ramzi F; Hunt, Julianne A; Kallashi, Florida; Hammond, Milton L; Chen, Ying; Eveland, Suzanne S; Guo, Qiu; Hyland, Sheryl A; Milot, Denise P; Cumiskey, Anne-Marie; Latham, Melanie; Rosa, Raymond; Peterson, Larry; Sparrow, Carl P; Wright, Samuel D; Anderson, Matt S; Sinclair, Peter J

    2011-03-15

    The development of 2-phenylbenzoxazoles as inhibitors of cholesteryl ester transfer protein (CETP) is described. Initial efforts aimed at engineering replacements for the aniline substructures in the benchmark molecule. Reversing the connectivity of the central aniline lead to a new class of 2-(4-carbonylphenyl)benzoxazoles. Structure-activity studies at the C-7 and terminal pyridine ring allowed for the optimization of potency and HDLc-raising efficacy in this new class of inhibitors. These efforts lead to the discovery of benzoxazole 11v, which raised HDLc by 24 mg/dl in our transgenic mouse PD model.

  15. Pion absorption in nuclei: The (. pi. /sup + -/,p) reactions

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, C.S.

    1987-05-01

    Reported here is the first experiment to measure the excitation of discrete final states following the (..pi../sup -/,p) reaction. The Energetic Pion Channel and Spectrometer (EPICS) at the Los Alamos National Laboratory and the High Resolution Pion Channel and Spectrometer (..pi..M1-SUSI) at the Swiss Institute for Nuclear Physics were used for this high resolution study of (..pi../sup + -/,p) reactions. An average energy resolution of 500 KeV and 700 KeV was achieved at EPICS and ..pi..M1-SUSI respectively. At EPICS these reactions were measured at T/sub ..pi../ = 120 MeV and theta/sub lab/ = 25/sup 0/ on /sup 24/Mg, /sup 27/Al, /sup 40/Ca and /sup 58/Ni; /sup 12/C(..pi../sup -/,p) was measured at T/sub ..pi../ = 145 MeV. At ..pi..M1-SUSI these reactions were measured at T/sub ..pi../ = 90 MeV and at theta/sub lab/ = 20/sup 0/ on /sup 23/Na and /sup 24/Mg. The measurement includes both the differential cross sections and continuum up to an excitation energy of 40 MeV. In /sup 23/Na, /sup 24/Mg, and /sup 27/Al there are peaks in the low excitation region. The shape of the continuum in an excitation energy range of 10 to 40 MeV was found to be independent of pion charge and target mass. The magnitude of proton yield from all the targets at T/sub ..pi../ = 120 MeV is more than twenty four times larger for ..pi../sup +/ than for ..pi../sup -/. Also, the cross sections for both reactions on /sup 24/Mg is slightly enhanced compared to other nuclei. At T/sub ..pi../ = 90 MeV the ratio of the proton yield for ..pi../sup +/ to ..pi../sup -/ absorption drops down to fourteen. This high ratio and its energy dependence supports the idea of a two nucleon pion absorption model. Pion absorption in the context of both the reaction mechanism and nuclear structure is discussed. 99 refs., 64 figs., 11 tabs.

  16. Tremorgenic Toxin from Penicillium verruculosum

    Science.gov (United States)

    Cole, R. J.; Kirksey, J. W.; Moore, J. H.; Blankenship, B. R.; Diener, U. L.; Davis, N. D.

    1972-01-01

    A new mycotoxin that produces severe tremors and acute toxicity when administered orally or intraperitoneally (ip) to mice and 1-day-old cockerels was obtained from a strain of Penicillium verruculosum Peyronel isolated from peanuts. The ip 50% lethal dose (LD50) of this tremorgen was 2.4 mg/kg in mice and 15.2 mg/kg in chickens. Orally administered LD50 values for the toxin were 126.7 mg/kg in mice and 365.5 mg/kg in chickens. The trivial name „verruculogen” is proposed for this tremorgenic mycotoxin. Physical and chemical characteristics of the mycotoxin are described. PMID:4341967

  17. Tremorgenic toxin from Penicillium veruculosum.

    Science.gov (United States)

    Cole, R J; Kirksey, J W; Moore, J H; Blankenship, B R; Diener, U L; Davis, N D

    1972-08-01

    A new mycotoxin that produces severe tremors and acute toxicity when administered orally or intraperitoneally (ip) to mice and 1-day-old cockerels was obtained from a strain of Penicillium verruculosum Peyronel isolated from peanuts. The ip 50% lethal dose (LD(50)) of this tremorgen was 2.4 mg/kg in mice and 15.2 mg/kg in chickens. Orally administered LD(50) values for the toxin were 126.7 mg/kg in mice and 365.5 mg/kg in chickens. The trivial name "verruculogen" is proposed for this tremorgenic mycotoxin. Physical and chemical characteristics of the mycotoxin are described.

  18. Eficacia de la Galantamina en los síntomas de demencia del tipo Alzheimer, vascular y mixta

    OpenAIRE

    José Luis Acosta-Patiño; Joaquín Jiménez-Alayola; Lucas López-Segovia; Manuel E. Borbolla-Sala

    2006-01-01

    Objetivo: evaluar la eficacia de la galantamina sobre los síntomas de demencia tipo Alzheimer, vascular o mixta en pacientes ambulatorios. Material y métodos: estudio experimental Fase IV en donde se incluyeron 32 pacientes con diagnóstico de demencia con base en el DSM-IV, se les administró solución gotas de galantamina con incremento gradual de la dosis, durante tres meses: 8, 16 y 24 mg/día, evaluando cada mes; tolerabilidad, eventos adversos, se aplicó y evaluó el minimental de Folstein. ...

  19. Paliperidone ER and oral risperidone in patients with schizophrenia: a comparative database analysis

    Directory of Open Access Journals (Sweden)

    Schooler Nina

    2011-02-01

    Full Text Available Abstract Background To compare the efficacy and tolerability of paliperidone extended-release (ER with risperidone immediate-release using propensity score methodology. Methods Six double-blind, randomized, placebo-controlled, short-term clinical trials for acute schizophrenia with availability of individual patient-level data were identified (3 per compound. Propensity score pairwise matching was used to balance observed covariates between the paliperidone ER and risperidone patient populations. Scores were generated using logistic regression models, with age, body mass index, race, sex, baseline Positive and Negative Syndrome Scale (PANSS total score and baseline Clinical Global Impressions–Severity (CGI-S score as factors. The dosage range of paliperidone ER (6-12 mg/day was compared with 2 risperidone dosage ranges: 2-4 and 4-6 mg/day. The primary efficacy measure was change in PANSS total score at week 6 end point. Tolerability end points included adverse event (AE reports and weight. AEs with rates ≥5% and with a ≥2% difference between paliperidone ER and risperidone were identified. Results Completion rates for placebo-treated subjects in paliperidone ER trials (n = 95 and risperidone trials (n = 122 groups were 36.8% and 51.6%, respectively; end point changes on PANSS total scores were similar (p = 0.768. Completion rates for subjects receiving paliperidone ER 6-12 mg/day (n = 179, risperidone 2-4 mg/day (n = 113 or risperidone 4-6 mg/day (n = 129 were 64.8%, 54.0% and 66.7%, respectively (placebo-adjusted rates: paliperidone ER vs risperidone 2-4 mg/day, p = 0.005; paliperidone ER vs risperidone 4-6 mg/day, p = 0.159. PANSS total score improvement with paliperidone ER was greater than with risperidone 2-4 mg/day (difference in mean change score, -6.7; p Conclusions This indirect database analysis suggested that paliperidone ER 6-12 mg/day may be more efficacious than risperidone 2-4 mg/day and as efficacious as risperidone 4-6 mg/day. The AE-adjusted incidence rates suggest differences between treatments that may be relevant for individual patients. Additional randomized, direct, head-to-head clinical trials are needed to confirm these findings.

  20. [Production of carotene and lycopene by mutants of Streptomyces globisporus 1912 cultivated on mealy media].

    Science.gov (United States)

    Holembiovs'ka, S L; Matseliukh, B P

    2008-01-01

    Carotenoids produced by strains 4Crt and 4Lcp, spontaneous mutants oflandomycin E producer Streptomyces globisporus 1912 with activated cryptic genes of carotenogenesis, were identified, and their quantitative output was studied after growth of Streptomycete cultures on different mealy media in shake flasks. On the basis of chromatographic mobility and maxima of absorption spectra of purified pigments they were related to lycopene, beta- and phi-carotene (isorenieratene). It was shown that strain 4Crt synthesizes both carotenoids, while its spontaneous mutant 4Lcp--only lycopene. The greatest output of lycopene (27.24 mg/l) was observed after cultivation of 4Lcp strain on soy-corn medium.

  1. Radiogenic Ingrowth of 40CA from Decay of 40K Provides a Powerful Tracer for Understanding the Origins of Felsic Magmas

    Science.gov (United States)

    Mills, Ryan D.; Simon, Justin I.; Depaolo, Donald J.; Bachmann, Olivier

    2013-01-01

    Over time high K/Ca continental crust produces a unique Ca isotopic reservoir, with measurable 40Ca excesses compared to Earth's mantle (?Ca=0). Thus, values of ?Cai > 1 indicate a significant crustal contribution to a magma. Values of ?Cai (<1) indistinguishable from mantle Ca indicate that the Ca in those magmas is either directly from the mantle, or is from partial melting of newly formed crust. So, whereas 40Ca excesses clearly define crustal contributions, mantle-like 40Ca/44Ca ratios are not as definitive. Here we present Ca isotopic measurements of intermediate to felsic igneous rocks from the western United States, and two crustal xenoliths found within the Fish Canyon Tuff (FCT). The two crustal xenoliths found within the 28.2 Ma FCT of the southern Rocky Mountain volcanic field (SRMVF) yield ?Ca values of 4 and 7.5, respectively. The 40Ca excesses of these possible source rocks are due to long-term in situ 40K decay and suggest that they are Precambrian in age. However, the FCT (?Cai 0.3) is within uncertainty of the mantle 40Ca/44Ca. Together, these data indicate that little Precambrian crust was involved in the petrogenesis of the FCT. Nd isotopic analyses of the FCT imply that it was generated from 10- 75% of an enriched component, and the Ca isotopic data appear to restrict that component to newly formed lower crust, or enriched mantle. However, the Ca isotopic data do permit assimilation of some crust with low Ca/Nd; decreasing the 143Nd/144Nd without adding much excess 40Ca to the FCT. Several other large tuffs from the SRMVF and from Yellowstone have ?Cai indistinguishable from the mantle. However, a few large tuffs from the SRMVF show significant 40Ca excesses. These tuffs (Wall Mountain, Blue Mesa, and Grizzly Peak) are likely sourced from near, or within the Colorado Mineral Belt. New isotopic measurements of Mesozoic and Tertiary granites from across the northern Great Basin show a range of ?Cai from 0 to 3. In these samples ?Cai is generally

  2. Calcium isotopic composition of mantle xenoliths and minerals from Eastern China

    Science.gov (United States)

    Kang, Jin-Ting; Zhu, Hong-Li; Liu, Yu-Fei; Liu, Fang; Wu, Fei; Hao, Yan-Tao; Zhi, Xia-Chen; Zhang, Zhao-Feng; Huang, Fang

    2016-02-01

    This study presents calcium isotope data for co-existing clinopyroxenes (cpx), orthopyroxenes (opx), and olivine (ol) in mantle xenoliths to investigate Ca isotopic fractionation in the upper mantle. δ44/40Ca (δ44/40Ca (‰) = (44Ca/40Ca)SAMPLE/(44Ca/40Ca)SRM915a - 1) in opx varies from 0.95 ± 0.05‰ to 1.82 ± 0.01‰ and cpx from 0.71 ± 0.06‰ to 1.03 ± 0.12‰ (2se). δ44/40Ca in ol (P-15) is 1.16 ± 0.08‰, identical to δ44/40Ca of the co-existing opx (1.12 ± 0.09‰, 2se). The Δ44/40Caopx-cpx (Δ44/40Caopx-cpx = δ44/40Caopx-δ44/40Cacpx) shows a large variation ranging from -0.01‰ to 1.11‰ and it dramatically increases with decreasing of Ca/Mg (atomic ratio) in opx. These observations may reflect the effect of opx composition on the inter-mineral equilibrium fractionation of Ca isotopes, consistent with the theoretical prediction by first-principles theory calculations (Feng et al., 2014). Furthermore, Δ44/40Caopx-cpx decreases when temperature slightly increases from 1196 to 1267 K. However, the magnitude of such inter-mineral isotopic fractionation (1.12‰) is not consistent with the value calculated by the well-known correlation between inter-mineral isotope fractionation factors and 1/T2 (Urey, 1947). Instead, it may reflect the temperature control on crystal chemistry of opx (i.e., Ca content), which further affects Δ44/40Caopx-cpx. The calculated δ44/40Ca of bulk peridotites and pyroxenites range from 0.76 ± 0.06‰ to 1.04 ± 0.12‰ (2se). Notably, δ44/40Ca of bulk peridotites are positively correlated with CaO and negatively with MgO content. Such correlations can be explained by mixing between a fertile mantle end-member and a depleted one with low δ44/40Ca, indicating that Ca isotopes could be a useful tool in studying mantle evolution.

  3. Interpreting the Marine Calcium Isotope Record: Influence of Reef Builders

    Science.gov (United States)

    Boehm, F.; Eisenhauer, A.; Farkas, J.; Kiessling, W.; Veizer, J.; Wallmann, K.

    2008-12-01

    The calcium isotopic composition of seawater as recorded in brachiopod shells varied substantially during the Paleozoic (Farkas et al. 2007, Geochim. Cosmochim. Acta, 71, 5117-5134). The most prominent feature of the record is an excursion to higher 44Ca/40Ca values that started during the Early Carboniferous and lasted until the Permian. The shift occurred shortly after the transition from a calcite-sea to an aragonite-sea (Sandberg 1983, Nature 305, 19-22; Stanley and Hardie 1998, Pal3, 144, 3-19). It therefore has been interpreted to reflect a change in the average calcium isotope fractionation of carbonates produced in the oceans. Aragonite is depleted by about 0.6 permil in 44Ca/40Ca compared to calcite (Gussone et al. 2005, Geochim. Cosmochim. Acta, 69, 4485-4494). Consequently a transient shift from calcite dominated to an aragonite dominated calcium carbonate sedimentation could have caused the observed 0.5 permil isotope shift. We compare the marine calcium isotope record with a new compilation of the Phanerozoic trends in the skeletal mineralogy of marine invertebrates (Kiessling et al. 2008, Nature Geoscience, 1, 527-530). The compilation is based on data collected in the PaleoReef database and the Paleobiology Database, which include information on Phanerozoic reef complexes and taxonomic collection data of Phanerozoic biota, respectively. We find a strong positive correlation between the calcium isotope ratios and the abundance of aragonitic reef builders from the Silurian until the Permian at a sample resolution of about 10 million years. The two records, however, diverge in the Triassic, when reefs were dominated by aragonite but the calcium isotope values remained at a relatively low level. We also find a good correlation between calcium isotopes and the proportion of aragonite in the general record of Phanerozoic biota. However, in this case the records start to diverge already in the latest Carboniferous. The observations suggest that the

  4. The effects of diagenesis and dolomitization on Ca and Mg isotopes in marine platform carbonates: Implications for the geochemical cycles of Ca and Mg

    Science.gov (United States)

    Fantle, Matthew S.; Higgins, John

    2014-10-01

    The Ca, Mg, O, and C isotopic and trace elemental compositions of marine limestones and dolostones from ODP Site 1196A, which range in depth (∼58 to 627 mbsf) and in depositional age (∼5 and 23 Ma), are presented. The objectives of the study are to explore the potential for non-traditional isotope systems to fingerprint diagenesis, to quantify the extent to which geochemical proxies are altered during diagenesis, and to investigate the importance of diagenesis within the global Ca and Mg geochemical cycles. The data suggest that Ca, which has a relatively high solid to fluid mass ratio, can be isotopically altered during diagenesis. In addition, the alteration of Ca correlates with the alteration of Mg in such a way that both can serve as useful tools for deciphering diagenesis in ancient rocks. Bulk carbonate δ44Ca values vary between 0.60 and 1.31‰ (SRM-915a scale); the average limestone δ44Ca is 0.97 ± 0.24‰ (1SD), identical within error to the average dolostone (1.03 ± 0.15 1SD ‰). Magnesium isotopic compositions (δ26Mg, DSM-3 scale) range between -2.59‰ and -3.91‰, and limestones (-3.60 ± 0.25‰) and dolostones (-2.68 ± 0.07‰) are isotopically distinct. Carbon isotopic compositions (δ13C, PDB scale) vary between 0.86‰ and 2.47‰, with average limestone (1.96 ± 0.31‰) marginally offset relative to average dolostone (1.68 ± 0.57‰). The oxygen isotopic compositions (δ18O, PDB scale) of limestones (-1.22 ± 0.94‰) are substantially lower than the dolostones measured (2.72 ± 1.07‰). The isotopic data from 1196A suggest distinct and coherent trends in isotopic and elemental compositions that are interpreted in terms of diagenetic trajectories. Numerical modeling supports the contention that such trends can be interpreted as diagenetic, and suggests that the appropriate distribution coefficient (KMg) associated with limestone diagenesis is ∼1 to 5 × 10-3, distinctly lower than those values (>0.015) reported in laboratory

  5. Multi-proxy study of Ocean Anoxic Event 2 (Cenomanian-Turonian) yields new perspective on the drivers for Mesozoic anoxic events

    Science.gov (United States)

    Sageman, B. B.; Hurtgen, M.; Jacobson, A. D.; Selby, D. S.

    2015-12-01

    Mesozoic ocean anoxic events have long been a focus of intense study because they appear to reflect a large-scale oscillation of the marine redox state from oxic to anoxic, and at least locally sulfidic. The consensus view on the cause of these events has changed over the past 39 years, since they were first defined. A global net increase in primary production is now widely accepted as the key driver, and the evidence for a volcanic trigger of this process is strong. However, the exact pathway from volcanism to OAE is less certain. Some authors favor the direct role of a massive load of reduced compounds in LIP hydrothermal fluxes for consuming available marine oxygen. Others prefer the indirect pathway of oxygen consumption by enhanced organic matter flux, which requires a major increase in nutrient budgets. Metallic micronutrients in the hydrothermal fluxes have been hypothesized, as have increases in riverine phosphorus fluxes due to enhanced weathering that would result from volcanic CO2 driven warming. Our recent work on the OAE2 interval has led to some new ideas about these hypothesized drivers. In particular, refinement of the Late Cenomanian time scale, and comparison of the geochemical records of d13C, d34S, Osi, P phases, and d44Ca between selected sections in North America and Europe has suggested the following sequence of events: 1) Osi data indicate that the onset of a major volcanic event precedes the positive shift in C-isotopes by at least 40 to possibly 180 kyr; 2) a positive shift in d44Ca data interpreted to indicate ocean acidification is coincident with the volcanic event; 3) the positive shift in C-isotopes is interpreted to reflect the accumulated burial of marine organic matter sufficient to shift the C-reservoir to heavier values; thus, our data suggest that up to 180 kyr was required for the shift in nutrient supply, productivity increase, and organic matter burial. Two mechanisms that conceivably match the lagged character of the event

  6. Angular correlation measurements for {sup 12}C{sup 12}C,{sup 12}C{sup 12}C 3{sup -} scattering

    Energy Technology Data Exchange (ETDEWEB)

    Wuosmaa, A.H.; Betts, R.R.; Freer, M.

    1995-08-01

    Previous studies of inelastic {sup 12}C + {sup 12}C scattering to a variety of final states identified significant resonance behavior in a number of different reaction channels. These resonances can be interpreted as either potential scattering resonances, or as population of cluster structures in the compound nucleus {sup 24}Mg, or as some interplay between the two mechanisms. Currently, for many of these resonances the situation remains unclear. One example is a large peak observed in the excitation function for the 3{sup -} - g.s. excitation, identified in previous work performed at the Daresbury Laboratory in England. This peak is observed at the same center-of-mass energy as one observed in the O{sub 2}{sup +}-O{sub 2}{sup +} inelastic scattering channel. That structure was suggested to correspond to exotic deformed configurations in the compound nucleus {sup 24}Mg. As the peak in the 3{sup -} + g.s. exit channel occurs at precisely the same energy as the purported resonance, it is tempting to associate the two. Before such an association can be confirmed or ruled out, further information must be obtained about the 3{sup -} + g.s. structure. In particular, it is important to determine the angular momenta that dominate the 3{sup -} + g.s. structure.

  7. Therapeutic effect of Intra-Tympanic Dexamethasone-Hyaluronic Acid Combination in Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Rogha, Mehrdad; Kalkoo, Amin

    2017-09-01

    Hearing loss is fairly a common disorder which is usually treated with corticosteroids via systemic administration and/or intra-tympanic injection. This study aimed to compare the effectiveness of intra-tympanic injections of dexamethasone with its combination with hyaluronic acid in patients with sudden sensorineural hearing loss. In this clinical trial, 40 patients were randomly assigned to two groups; in the first group, 20 patients received 2.4 mg intra-tympanic dexamethasone, while in the second group patients received injections of 2.4 mg of dexamethasone plus 2 mg of hyaluronic acid in combination. Patients in both groups were injected every other day to a total of three injections. The hearing status of patients was evaluated by pure tone audiometry (bone conduction threshold) before and 2 weeks after the intervention. Assessment of hearing threshold before and after treatment in the two groups showed a significant difference between hearing thresholds at frequencies of 4,000 to 8,000 Hz (Psudden sensorineural hearing loss may be more effective than dexamethasone alone. Because hyaluronic acid lacks certain side effects, and also makes it possible to reduce the steroid dose, we recommend the use of this combination in the treatment of patients with sudden sensorineural hearing loss.

  8. Therapeutic effect of Intra-Tympanic Dexamethasone–Hyaluronic Acid Combination in Sudden Sensorineural Hearing Loss

    Directory of Open Access Journals (Sweden)

    Mehrdad Rogha

    2017-09-01

    Full Text Available Introduction: Hearing loss is fairly a common disorder which is usually treated with corticosteroids via systemic administration and/or intra-tympanic injection. This study aimed to compare the effectiveness of intra-tympanic injections of dexamethasone with its combination with hyaluronic acid in patients with sudden sensorineural hearing loss.   Materials and Methods: In this clinical trial, 40 patients were randomly assigned to two groups; in the first group, 20 patients received 2.4 mg intra-tympanic dexamethasone, while in the second group patients received injections of 2.4 mg of dexamethasone plus 2 mg of hyaluronic acid in combination. Patients in both groups were injected every other day to a total of three injections. The hearing status of patients was evaluated by pure tone audiometry (bone conduction threshold before and 2 weeks after the intervention.   Results: Assessment of hearing threshold before and after treatment in the two groups showed a significant difference between hearing thresholds at frequencies of 4,000 to 8,000 Hz (P

  9. Probing the statistical decay and alpha-clustering effects in 12c+12c and 14n+10b reactions

    CERN Document Server

    Morelli, Luca; Agostino, M D; Bruno, M; Gulminelli, F; Cinausero, M; Degerlier, M; Fabris, D; Gramegna, F; Marchi, T; Barlini, S; Bini, M; Casini, G; Gelli, N; Lopez, A; Pasquali, G; Piantelli, S; Valdre', S

    2013-01-01

    An experimental campaign has been undertaken at INFN Laboratori Nazionali di Legnaro, Italy, in order to progress in our understanding of the statistical properties of light nuclei at excitation energies above particle emission threshold, by measuring exclusive data from fusion-evaporation reactions. A first reaction 12C+12C at 7.9 AMeV beam energy has been measured, using the GARFIELD+Ring Counter experimental setup. Fusion-evaporation events have been exclusively selected. The comparison to a dedicated Hauser-Feshbach calculation allows us to give constraints on the nuclear level density at high excitation energy for light systems ranging from C up to Mg. Out-of-equilibrium emission has been evidenced and attributed both to entrance channel effects favoured by the cluster nature of reaction partners and, in more dissipative events, to the persistence of cluster correlations well above the 24Mg threshold for 6 alphas decay. The 24Mg compound nucleus has been studied with a new measurement 14N + 10B at 5.7 AM...

  10. Effect of selenium on control of postharvest gray mould of tomato fruit and the possible mechanisms involved

    Directory of Open Access Journals (Sweden)

    Zhilin eWu

    2016-01-01

    Full Text Available Selenium (Se has important benefits for crop growth and stress tolerance at low concentrations. However, there is very little information on antimicrobial effect of selenium against the economically important fungus Botrytis cinerea. In the present study, using sodium selenite as Se source, we investigated the effect of Se salts on spore germination and mycelial growth of the fungal pathogen in vitro and gray mould control in harvested tomato fruit. Se treatment at 24 mg/L significantly inhibited spore germination of the fungal pathogen and effectively controlled gray mould in harvested tomato fruit. Se treatment at 24 mg/L seems to induce the generation of intracellular reactive oxygen species in the fungal spores. The membrane integrity damage was observed with fluorescence microscopy following staining with propidium iodide after treatment of the spores with Se. These results suggest that Se has the potential for controlling gray mould rot of tomato fruits and might be useful in integrated control against gray mould disease of postharvest fruits and vegetables caused by B. cinerea. The mechanisms by which Se decreased gray mould decay of tomato fruit may be directly related to the severe damage to the conidia plasma membrane and loss of cytoplasmic materials from the hyphae.

  11. Assessment of toxic effects of triclosan on the terrestrial snail (Achatina fulica).

    Science.gov (United States)

    Wang, Xiaonan; Liu, Zhengtao; Wang, Wanhua; Yan, Zhenguang; Zhang, Cong; Wang, Weili; Chen, Lihong

    2014-08-01

    Triclosan (TCS) is a broad-spectrum antimicrobial agent used in personal care products, and as a result, is widespread in the environment. Toxicity tests of TCS on aquatic organisms have been reported, but limited toxicity data on terrestrial species are available. In this study, the 28-d chronic toxicity of TCS on the biomass, shell diameter growth, and total food intake of the terrestrial snail Achatina fulica were tested. Moreover, biochemical responses, including changes in the activity of catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), and the content of malondialdehyde (MDA), were examined after 14-d and 28-d exposure. Results showed that TCS had toxic effects on the biomass, shell diameter growth, and total food intake of A. fulica with no observed effect concentration (NOEC) values of 24 mg kg(-1). As for the antioxidant enzymes, TCS caused significant oxidative stress even at the low concentration of 24 mg kg(-1). The CAT and POD activities at the high concentrations of 200 and 340 mg kg(-1), respectively, were significantly inhibited. The SOD and CAT activity in treatments below 118 mg kg(-1) and the MDA content in all treatments showed dose-effect relationships. This study demonstrated that TCS caused adverse effects on terrestrial invertebrates, and provided valuable information for the risk assessment imposed by TCS in the terrestrial environment.

  12. 鲜食枣新品种‘京枣60’%A New Fresh Consuming Jujube Cultivar‘Jingzao 60’

    Institute of Scientific and Technical Information of China (English)

    潘青华; 张玉平; 白金; 金万梅; 李少宁

    2011-01-01

    ‘Jingzao 60’is a new jujube cultivar which was selected from a Beijing’s ancient satus jujube’s tree after many times grafting and regional testing. The fruit shape is near cone. The average mass of single fruit is 25.6 g. The color of mature fruit is purple,The flesh is crisp and contains abundant sweet juice. The soluble solids content is 26%,The total sugar content is 18.6%,vitamin C content is 3.24 mg · g-1,and titratable acidity is 0.54%. The quality is excellent. The fruit matures in mid-late September in Beijing.%‘京枣60’是从北京市古城区收集的实生枣树资源中经过多代改接和区域试验而选育出的枣新品种,果实近圆锥形,平均单果质量25.6g,成熟果紫红色,果肉酥脆,汁多味甜,鲜枣可溶性固形物26%,总糖18.6%,维生素C3.24mg·g-1,可滴定酸0.54%,品质优良,在北京地区成熟期为9月中下旬。

  13. The Dose-response of Intrathecal Ropivacaine Co-administered with Sufentanil for Cesarean Delivery under Combined Spinal-epidural Anesthesia in Patients with Scarred Uterus

    Science.gov (United States)

    Xiao, Fei; Xu, Wen-Ping; Zhang, Yin-Fa; Liu, Lin; Liu, Xia; Wang, Li-Zhong

    2015-01-01

    Background: Spinal anesthesia is considered as a reasonable anesthetic option in lower abdominal and lower limb surgery. This study was to determine the dose-response of intrathecal ropivacaine in patients with scarred uterus undergoing cesarean delivery under combined spinal-epidural anesthesia. Methods: Seventy-five patients with scarred uterus undergoing elective cesarean delivery under combined spinal-epidural anesthesia were enrolled in this randomized, double-blinded, dose-ranging study. Patients received 6, 8, 10, 12, or 14 mg intrathecal hyperbaric ropivacaine with 5 μg sufentanil. Successful spinal anesthesia was defined as a T4 sensory level achieved with no need for epidural supplementation. The 50% effective dose (ED50) and 95% effective dose (ED95) were calculated with a logistic regression model. Results: ED50 and ED95 of intrathecal hyperbaric ropivacaine for patients with scarred uterus undergoing cesarean delivery under combined spinal-epidural anesthesia (CSEA) were 8.28 mg (95% confidence interval [CI]: 2.28–9.83 mg) and 12.24 mg (95% CI: 10.53–21.88 mg), respectively. Conclusion: When a CSEA technique is to use in patients with scarred uterus for an elective cesarean delivery, the ED50 and ED95 of intrathecal hyperbaric ropivacaine along with 5 μg sufentanil were 8.28 mg and 12.24 mg, respectively. In addition, this local anesthetic is unsuitable for emergent cesarean delivery, but it has advantages for ambulatory patients. PMID:26415793

  14. On Quasibound N* Nuclei

    CERN Document Server

    Kelkar, N G; Moskal, P

    2015-01-01

    The possibility for the existence of unstable bound states of the S11 nucleon resonance N$^*$(1535) and nuclei is investigated. These quasibound states are speculated to be closely related to the existence of the quasibound states of the eta mesons and nuclei. Within a simple model for the N N$^*$ interaction involving a pion and eta meson exchange, N$^*$-nucleus potentials for N*-$^3$He and N*-$^{24}$Mg are evaluated and found to be of a Woods-Saxon like form which supports two to three bound states. In case of N*-$^3$He, one state bound by only a few keV and another by 4 MeV is found. The results are however quite sensitive to the N N$^*$ $\\pi$ and N N$^*$ $\\eta$ vertex parameters. A rough estimate of the width of these states, based on the mean free path of the exchanged mesons in the nuclei leads to very broad states with $\\Gamma \\sim$ 80 and 110 MeV for N*-$^3$He and N*-$^{24}$Mg respectively.

  15. Nuclear alpha-clustering, superdeformation, and molecular resonances

    CERN Document Server

    Beck, C

    2004-01-01

    Nuclear alpha-clustering has been the subject of intense study since the advent of heavy-ion accelerators. Looking back for more than 40 years we are able today to see the connection between quasimolecular resonances in heavy-ion collisions and extremely deformed states in light nuclei. For example superdeformed bands have been recently discovered in light N=Z nuclei such as $^{36}$Ar, $^{40}$Ca, $^{48}$Cr, and $^{56}$Ni by $\\gamma$-ray spectroscopy. The search for strongly deformed shapes in N=Z nuclei is also the domain of charged-particle spectroscopy, and our experimental group at IReS Strasbourg has studied a number of these nuclei with the charged particle multidetector array {\\sc Icare} at the {\\sc Vivitron} Tandem facility in a systematical manner. Recently the search for $\\gamma$-decays in $^{24}$Mg has been undertaken in a range of excitation energies where previously nuclear molecular resonances were found in $^{12}$C+$^{12}$C collisions. The breakup reaction $^{24}$Mg$+^{12}$C has been investigate...

  16. Measurements of proton induced γ-ray emission cross-sections on Mg from 1.0 to 3.0 MeV

    Science.gov (United States)

    Sharifzadeh, N.; Kakuee, O.; Mohammadi, S.

    2016-04-01

    Differential cross-section of proton induced γ-ray emission from the reactions 24Mg(p,p‧γ)24Mg (Eγ = 1369 keV), 25Mg(p,p‧γ)25Mg (Eγ = 390, 585, 975 keV) and 26Mg(p,γ)27Al (Eγ = 1014 keV) were measured for proton energies from 1 to 3 MeV using a 60 μg/cm2 Mg target evaporated on a 40 μg/cm2 Ag thin film. The γ-rays were collected by a 50% relative efficiency HPGe detector placed at an angle of 90° with respect to the beam direction, while the backscattered protons were collected by an ion implanted Si detector placed at a scattering angle of 165°. Simultaneous collection of γ-ray and RBS spectra is a great advantage of this approach which makes differential cross-section measurements independent on the collected beam charge. Measured cross-section values were compared with the previously reported data in the literature. Absolute γ-ray differential cross-sections were obtained with an overall systematic uncertainty of about ±6% and statistical uncertainty of less than ±5% for proton energies higher than 2.24 MeV.

  17. Interplay of projectile breakup and target excitation in reactions induced by weakly-bound nuclei

    CERN Document Server

    Gomez-Ramos, M

    2016-01-01

    In this work, we reexamine the extension of the CDCC formalism to include target excitation and apply it to a variety of reactions to study the effect of breakup on inelastic cross sections. We use a transformed oscillator basis to discretize the continuum of the projectiles in the different reactions and use the extended CDCC method developed in this work to solve the resulting coupled differential equations. A new code has been developed to perform the calculations. Reactions 58Ni(d, d) 58Ni*, 24Mg(d, d) 24Mg* , 144Sm( 6Li, 6Li) 144Sm* and 9Be( 6Li, 6Li) 9Be* are studied. Satisfactory agreement is found between experimental data and extended CDCC calculations. The studied CDCC method is proved to be an accurate tool to describe target excitation in reactions with weakly-bound nuclei. Moderate effects of breakup on inelastic observables are found for the reactions studied. Cross section magnitudes are not modified much, but angular distributions present smoothing when opposed to calculations without breakup.

  18. Mephedrone (4-methylmethcathinone)-related deaths.

    Science.gov (United States)

    Maskell, Peter D; De Paoli, Giorgia; Seneviratne, Collin; Pounder, Derrick J

    2011-04-01

    Four deaths related to the drug 4-methylmethcathinone (mephedrone) are reported. Qualitative and quantitative analysis of mephedrone was performed by high-performance liquid chromatography-diode-array detection. Of the four deaths, one was attributed to the adverse effects of mephedrone, with cardiac fibrosis and atherosclerotic coronary artery disease as a contributing factor. A 49-year-old female insufflated mephedrone; analysis disclosed mephedrone in femoral venous blood (0.98 mg/L). The second death was attributed solely to mephedrone. A 19-year-old male took mephedrone as well as alcohol and "ecstasy"; analysis disclosed mephedrone (2.24 mg/L femoral venous blood) and 3-trifluoromethylphenylpiperazine (3-TFMPP). In the third fatality, a 55-year-old female was found dead in bed; the death was attributed to the combined effects of mephedrone and methadone. Analysis of femoral venous blood revealed the prescribed drugs diazepam, nordiazepam, olazepine, and chlorpromazine metabolites together with methadone (0.3 mg/L) and mephedrone (0.13 mg/L). In the fourth case, a 17-year-old male car driver was involved in a vehicular collision and died of multiple blunt force injuries. Analysis revealed mephedrone in femoral venous blood (0.24 mg/L).

  19. Mixed-Symmetry Shell-Model Calculations in Nuclear Physics

    CERN Document Server

    Gueorguiev, V G

    2010-01-01

    We consider a novel approach to the nuclear shell model. The one-dimensional harmonic oscillator in a box is used to introduce the concept of an oblique-basis shell-model theory. By implementing the Lanczos method for diagonalization of large matrices, and the Cholesky algorithm for solving generalized eigenvalue problems, the method is applied to nuclei. The mixed-symmetry basis combines traditional spherical shell-model states with SU(3) collective configurations. We test the validity of this mixed-symmetry scheme on 24Mg and 44Ti. Results for 24Mg, obtained using the Wilthental USD intersection in a space that spans less than 10% of the full-space, reproduce the binding energy within 2% as well as an accurate reproduction of the low-energy spectrum and the structure of the states - 90% overlap with the exact eigenstates. In contrast, for an m-scheme calculation, one needs about 60% of the full space to obtain compatible results. Calculations for 44Ti support the mixed-mode scheme although the pure SU(3) ca...

  20. Antidepressant-like activity of (4-phenylpiperazin-1-yl) (quinoxalin-2-yl) methanone (4a), a novel 5-HT(3) receptor antagonist: an investigation in behaviour-based rodent models of depression.

    Science.gov (United States)

    Mahesh, Radhakrishnan; Kumar, Baldev; Jindal, Ankur; Bhatt, Shvetank; Devadoss, Thangaraj; Pandey, Dilip Kumar

    2012-01-01

    The present study was designed to investigate the antidepressant potential of (4-phenylpiperazin-1-yl) (quinoxalin-3-yl) methanone (4a), a novel 5-HT(3) receptor antagonist, with an optimal log P (2.84) and pA(2) value (7.3) greater than ondansetron (6.9) using rodent behavioural models of depression. Swiss albino mice were used in actophotometer test, forced swim test (FST) and 5-hydroxytryptophan (5-HTP) induced head twitch response. Reserpine induced hypothermia (RIH) and olfactory bulbectomy were performed in male Wistar rats. Statistical analysis was carried out by using one-way analysis of variance followed by Tukey's test. Acute treatment of 4a (1-4 mg/kg, i.p.) in mice produced antidepressant-like effects in FST without affecting the baseline locomotion in actophotometer test. Further, 4a (2-4 mg/kg, i.p.) potentiated the 5-HTP induced head twitches response in mice and also antagonized RIH in rats. Furthermore, sub-chronic (14 days) treatment with 4a (2-4 mg/ kg, p.o.) significantly attenuated the behavioural anomalies induced by bilateral olfactory bulbectomy in rats in modified open field exploration. These preliminary investigations confirm that 4a exhibits antidepressant-like activity in behaviour based rodent models of depression.

  1. 浊点萃取-间接光度法测定饮料中VC%Determination of Vitamin C in Drink by Indirec Spectrophotometric with Cloud Point Extraction

    Institute of Scientific and Technical Information of China (English)

    朱圣平; 丁宗庆

    2015-01-01

    A new method for the determination of vitamin C by indirec spectrophotometric after cloud point extraction was proposed. The effects of experimental conditions such as pH value, reagent dosage, equilibration temperature and time on cloud point extraction were discussed. a good linear relationship was obtained in the range of 4.0 mg/L-140 mg/L of the vitamin C (r=0.999 5), the detection limits of 2.24 mg/L. The recoveries fell in the range from 97.6%to 102.2%and the relative standard deviations were between 1.7%and 2.4%. This method has been applied for the determination of VC in drink samples.%建立了浊点萃取-间接分光光度法测定饮料中VC的方法.优化了pH、试剂用量、平衡温度和时间等条件.该方法的线性范围4.0 mg/L~140 mg/L(r=0.999 5),检出限为2.24 mg/L,加标回收率在97.6%~102.2%之间,相对标准偏差在1.7%~2.4%之间.成功的应用于饮料样品中VC的测定.

  2. The Abundance Evolution of Oxygen, Sodium and Magnesium in Extremely Metal-Poor Intermediate Mass Stars: Implications for the Self-Polution Scenario in Globular Clusters

    CERN Document Server

    Denissenkov, P A

    2003-01-01

    We present full stellar evolution and parametric models of the surface abundance evolution of O16, Ne22, Na23 and the magnesium isotopes in an extremely metal-poor intermediate mass star M_ZAMS=5M_sun, Z=0.0001. O16 and Ne22 are injected into the envelope by the third dredge-up following thermal pulses on the asymptotic giant branch. These species and the initially present Mg24 are depleted by hot bottom burning (HBB) during the interpulse phase. As a result, Na23, Mg25 and Mg26 are enhanced. If the HBB temperatures are sufficiently high for this process to deplete oxygen efficiently, Na23 is first produced and then depleted during the interpulse phase. Although the simultaneous depletion of O16 and enhancement of Na23 is possible, the required fine tuning of the dredge-up and HBB casts some doubt on the robustness of this process as the origin of the O-Na anti-correlation observed in globular cluster stars. However, a very robust prediction of our models are low Mg24/Mg25 and Mg24/Mg26 ratios whenever signif...

  3. Kinetic study of degradation of methyl orange on TiO_2 film%TiO_2薄膜降解甲基橙动力学研究

    Institute of Scientific and Technical Information of China (English)

    贾彩云; 吴迪

    2012-01-01

    采用450 W汞灯做光源,对TiO2薄膜光催化氧化甲基橙进行动力学研究。结果显示:TiO2薄膜光催化氧化甲基橙的动力学可用Langmuir-Hinshelwood(L-H)方程描述。甲基橙初始浓度≤20 mg/L时,TiO2薄膜光催化氧化甲基橙表现为一级反应;甲基橙初始浓度≥24 mg/L时,则表现为零级反应。%Using 450W mercury lamp as light source,the kinetics of degradation of methyl orange with TiO2 thin films were studied.The results showed that the degradation rate of methyl orange solution could be described by the Langmuir-Hinshelwood(L-H) kinetic equation.As the original concentration of methyl orange less than or equal to 20 mg/L,the photocatalytic oxidation of methyl orange on TiO2 films followed the first-order reaction kinetics;and after more than 24 mg/L,the methyl orange reaction turned to a zero-order reaction.

  4. Interplay of projectile breakup and target excitation in reactions induced by weakly bound nuclei

    Science.gov (United States)

    Gómez-Ramos, M.; Moro, A. M.

    2017-03-01

    Background: Reactions involving weakly bound nuclei require formalisms able to deal with continuum states. The majority of these formalisms struggle to treat collective excitations of the systems involved. For continuum-discretized coupled channels (CDCC), extensions to include target excitation have been developed but have only been applied to a small number of cases. Purpose: In this work, we reexamine the extension of the CDCC formalism to include target excitation and apply it to a variety of reactions to study the effect of breakup on inelastic cross sections. Methods: We use a transformed oscillator basis to discretize the continuum of the projectiles in the different reactions and use the extended CDCC method developed in this work to solve the resulting coupled differential equations. A new code has been developed to perform the calculations. Results: Reactions 58Ni(d ,d )*58Ni , 24Mg(d ,d )*24Mg , 144Sm(6Li,6Li)*144Sm , and 9Be(6Li,6Li)*9Be are studied. Satisfactory agreement is found between experimental data and extended CDCC calculations. Conclusions: The studied CDCC method has proven to be an accurate tool to describe target excitation in reactions with weakly bound nuclei. Moderate effects of breakup on inelastic observables are found for the reactions studied. Cross-section magnitudes are not modified much, but angular distributions present smoothing when opposed to calculations without breakup.

  5. The missing halide: Millimeter-wave spectroscopy of the MgI radical (X2Σ+)

    Science.gov (United States)

    Kilchenstein, K. M.; Halfen, D. T.; Ziurys, L. M.

    2017-09-01

    The pure rotational spectrum of the MgI radical in its ground electronic state (X2Σ+) has been measured using millimeter/submillimeter wave direct absorption techniques in the region of 200-300 GHz. The molecule was created in a DC discharge by the reaction of magnesium vapor, produced in a Broida-type oven, with CH3I. Between five to twelve transitions were recorded for the v = 0, 1, and 2 vibrational states of 24MgI, as well as the v = 0 state for the isotopologues 25MgI and 26MgI, measured in their natural magnesium abundance. All observed transitions exhibited large spin-rotation splittings. Rotational, centrifugal distortion, and spin-rotation constants were determined for each isotopologue and the excited vibrational states of 24MgI. Equilibrium parameters Be, αe, De, βe, γe and γe‧ were derived for the main isotopologue, as well as the equilibrium bond length, re = 2.5730 (1) Å. The large spin-rotation constant of γ ∼ 300 MHz in MgI is thought to arise from second-order spin-orbit coupling originating in the nearby A2Π state, with possible contributions from other excited 2Π states.

  6. [Preemptive randomized, double-blind study with lornoxicam in gynecological surgery].

    Science.gov (United States)

    Trampitsch, E; Pipam, W; Moertl, M; Sadjak, A; Dorn, C; Sittl, R; Likar, R

    2003-01-01

    Lornoxicam is a non opioid analgesic belonging to the oxicam group. The aim of this study was to determine whether lornoxicam has a preemptive analgesic effect. This study was carried out in a randomized, double-blind fashion with 66 patients divided into three groups undergoing gynecological operations. Group I was administered 8 mg of lornoxicam i.v. preoperatively followed by an 8-mg bolus every 8 h for a total dose of 24 mg in the first 24 h. Group II was administered 8 mg of lornoxicam i.v. bolus before the end of the operation followed by 8 mg every 8 h for a total dose of 24 mg in the first 24 h. Group III was administered placebo before and after the operation and for the first 24 h. The effectiveness was assessed postoperatively using the visual analogue scale (at rest, on exertion) and by calculating the total analgesic consumption of morphine hydrochloride in the first 24 h following operation. Vital signs and side effects were documented. Groups I and II demonstrated significantly reduced pain scores compared to group III at various points in time. Group I also demonstrated a weakly significant reduction in analgesic consumption of morphine hydrochloride postoperatively compared to groups II and III. Lornoxicam administered preemptively appears to improve the quality of postoperative analgesia and lead to reduced consumption of opioid analgesics postoperatively in patients undergoing gynecological operations.

  7. Determination of difference of boron content in soybean and its product yuba by ICP - AES%ICP - AES 法测定大豆及其产品腐竹中硼含量

    Institute of Scientific and Technical Information of China (English)

    杨大鹏; 刘晶

    2016-01-01

    The boron content in three different kinds of bean and their products yubas were determined by inductively coupled plasma - atomic emission spectrometry (ICP - AES)to research the migration of boron during the process of yubas and the relationship of boron content between different beans and yubas. The results showed that the boron contents were detected in all of the three kinds of beans, and the content was between 18 ~ 24 mg / kg. The boron contents in yubas were different because of the beans,but the mobilitys of boron were independent of the species of bean,were all between 60% ~ 67% .%为了研究腐竹生产过程中硼元素的迁移,通过ICP - AES对三种不同原料豆和对应生产的腐竹中硼含量进行检测,探索不同原料豆与腐竹中硼含量之间的关系。结果表明,三种豆中均含有一定量的硼,范围在18~24 mg / kg之间。腐竹中硼含量随原料豆不同而不同,但其迁移率与原料种类无关,都在60%~67%之间。

  8. Production of secondary particles and nuclei in cosmic rays collisions with the interstellar gas using the FLUKA code

    CERN Document Server

    Mazziotta, M N; Ferrari, A; Gaggero, D; Loparco, F; Sala, P R

    2016-01-01

    The measured fluxes of secondary particles produced by the interactions of Cosmic Rays (CRs) with the astronomical environment play a crucial role in understanding the physics of CR transport. In this work we present a comprehensive calculation of the secondary hadron, lepton, gamma-ray and neutrino yields produced by the inelastic interactions between several species of stable or long-lived cosmic rays projectiles (p, D, T, 3He, 4He, 6Li, 7Li, 9Be, 10Be, 10B, 11B, 12C, 13C, 14C, 14N, 15N, 16O, 17O, 18O, 20Ne, 24Mg and 28Si) and different target gas nuclei (p, 4He, 12C, 14N, 16O, 20Ne, 24Mg, 28Si and 40Ar). The yields are calculated using FLUKA, a simulation package designed to compute the energy distributions of secondary products with large accuracy in a wide energy range. The present results provide, for the first time, a complete and self-consistent set of all the relevant inclusive cross sections regarding the whole spectrum of secondary products in nuclear collisions. We cover, for the projectiles, a ki...

  9. Diffusion of Ca and Mg in Calcite

    Energy Technology Data Exchange (ETDEWEB)

    Cygan, R.T.; Fisler, D.K.

    1999-02-10

    The self-diffusion of Ca and the tracer diffusion of Mg in calcite have been experimentally measured using isotopic tracers of {sup 25}Mg and {sup 44}Ca. Natural single crystals of calcite were coated with a thermally-sputtered oxide thin film and then annealed in a CO{sub 2} gas at one atmosphere total pressure and temperatures from 550 to 800 C. Diffusion coefficient values were derived from the depth profiles obtained by ion microprobe analysis. The resultant activation energies for Mg tracer diffusion and Ca self-diffusion are respectively: E{sub a}(Mg) = 284 {+-} 74 kJ/mol and E{sub a}(Ca) = 271 {+-} 80 kJ/mol. For the temperature ranges in these experiments, the diffusion of Mg is faster than Ca. The results are generally consistent in magnitude with divalent cation diffusion rates obtained in previous studies and provide a means of interpreting the thermal histories of carbonate minerals, the mechanism of dolomitization, and other diffusion-controlled processes. The results indicate that cation diffusion in calcite is relatively slow and cations are the rate-limiting diffusing species for the deformation of calcite and carbonate rocks. Application of the calcite-dolomite geothermometer to metamorphic assemblages will be constrained by cation diffusion and cooling rates. The direct measurement of Mg tracer diffusion in calcite indicates that dolomitization is unlikely to be accomplished by Mg diffusion in the solid state but by a recrystallization process.

  10. Copper availability and bioavailability are controlled by rhizosphere pH in rape grown in an acidic Cu-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Chaignon, Valerie; Quesnoit, Marie [INRA, UMR 1222 Eco and Sols Ecologie fonctionnelle and Biogeochimie des Sols (INRA-IRD-SupAgro), Place Viala, F-34060 Montpellier (France); Hinsinger, Philippe, E-mail: philippe.hinsinger@supagro.inra.f [INRA, UMR 1222 Eco and Sols Ecologie fonctionnelle and Biogeochimie des Sols (INRA-IRD-SupAgro), Place Viala, F-34060 Montpellier (France)

    2009-12-15

    We evaluated how root-induced changes in rhizosphere pH varied and interacted with Cu availability and bioavailability in an acidic soil. Rape was grown on a Cu-contaminated acidic soil, which had been limed at 10 rates. Soil Cu bioavailability was not influenced by liming. However, liming significantly decreased CaCl{sub 2}-extracted Cu for pH between 3.7 and 5.1. Little effect was found for pH above 5.1. For soil pH < 4.4, CaCl{sub 2}-Cu contents were smaller in rhizosphere than uncropped soil. Rhizosphere alkalisation occurred at pH < 4.8, while acidification occurred at greater pH. This explained the changes of CaCl{sub 2}-Cu in the rhizosphere at low pH and the absence of pH dependency of Cu bioavailability to rape. In addition, apoplastic Cu in roots increased with increasing soil pH, most probably as a result of increased dissociation and affinity of cell wall compounds for Cu. - Root-induced increase in pH reduces Cu availability in the rhizosphere and Cu bioavailability to rape.

  11. Calcium and calcium isotope changes during carbon cycle perturbations at the end-Permian

    Science.gov (United States)

    Komar, Nemanja; Zeebe, Richard

    2016-04-01

    Negative carbon and calcium isotope excursions, as well as climate shifts, took place during the most severe mass extinction event in Earth's history, the end-Permian (˜252 Ma). Investigating the connection between carbon and calcium cycles during transient carbon cycle perturbation events, such as the end-Permian, may help resolve the intricacies between the coupled calcium-carbon cycles, as well as provide a tool for constraining the causes of mass extinction. Here, we identify the deficiencies of a simplified calcium model employed in several previous studies and we demonstrate the importance of a fully coupled carbon-cycle model when investigating the dynamics of carbon and calcium cycling. Simulations with a modified version of the LOSCAR model, which includes a fully coupled carbon-calcium cycle, indicate that increased weathering rates and ocean acidification (potentially caused by Siberian Trap volcanism) are not capable of producing trends observed in the record, as previously claimed. Our model results suggest that combined effects of carbon input via Siberian Trap volcanism (12,000 Pg C), the cessation of biological carbon export, and variable calcium isotope fractionation (due to a change in the seawater carbonate ion concentration) represents a more plausible scenario. This scenario successfully reconciles δ13C and δ44Ca trends observed in the sediment record, as well as the proposed warming of >6oC.

  12. Experimental study of the isovector giant dipole resonance in 80Zr and 81Rb

    Science.gov (United States)

    Ceruti, S.; Camera, F.; Bracco, A.; Mentana, A.; Avigo, R.; Benzoni, G.; Blasi, N.; Bocchi, G.; Bottoni, S.; Brambilla, S.; Crespi, F. C. L.; Giaz, A.; Leoni, S.; Million, B.; Morales, A. I.; Nicolini, R.; Pellegri, L.; Riboldi, S.; Wieland, O.; Bazzacco, D.; Ciemala, M.; Farnea, E.; Gottardo, A.; Kmiecik, M.; Maj, A.; Mengoni, D.; Michelagnoli, C.; Modamio, V.; Montanari, D.; Napoli, D.; Recchia, F.; Sahin, E.; Ur, C.; Valiente-Dobón, J. J.; Wasilewska, B.; Zieblinski, M.

    2017-01-01

    The isovector giant dipole resonance (IVGDR) γ decay was measured in the compound nuclei 80Zr and 81Rb at an excitation energy of E*=54 MeV. The fusion reaction 40Ca+40Ca at Ebeam=136 MeV was used to form the compound nucleus 80Zr, while the reaction 37Cl+44Ca at Ebeam=95 MeV was used to form the compound nucleus 81Rb at the same excitation energy. The IVGDR parameters extracted from the analysis were compared with the ones found at higher excitation energy (E*=83 MeV). The comparison allows one to observe two different nuclear mechanisms: (i) the IVGDR intrinsic width remains constant with the excitation energy in the nucleus 81Rb; (ii) the isospin-violating spreading width (i.e., Coulomb spreading width) remains constant with the excitation energy in the nucleus 80Zr. The experimental setup used for the γ -ray detection was composed by the AGATA demonstrator array coupled to the large-volume LaBr3:Ce detectors of the HECTOR+ array.

  13. Calcium isotope fractionation between aqueous compounds relevant to low-temperature geochemistry, biology and medicine.

    Science.gov (United States)

    Moynier, Frédéric; Fujii, Toshiyuki

    2017-03-09

    Stable Ca isotopes are fractionated between bones, urine and blood of animals and between soils, roots and leaves of plants by >1000 ppm for the (44)Ca/(40)Ca ratio. These isotopic variations have important implications to understand Ca transport and fluxes in living organisms; however, the mechanisms of isotopic fractionation are unclear. Here we present ab initio calculations for the isotopic fractionation between various aqueous species of Ca and show that this fractionation can be up to 3000 ppm. We show that the Ca isotopic fractionation between soil solutions and plant roots can be explained by the difference of isotopic fractionation between the different first shell hydration degree of Ca(2+) and that the isotopic fractionation between roots and leaves is controlled by the precipitation of Ca-oxalates. The isotopic fractionation between blood and urine is due to the complexation of heavy Ca with citrate and oxalates in urine. Calculations are presented for additional Ca species that may be useful to interpret future Ca isotopic measurements.

  14. Simulation of geochemical processes responsible for the formation of the Zhezqazghan deposit

    Science.gov (United States)

    Ryzhenko, B. N.; Cherkasova, E. V.

    2014-05-01

    Physicochemical computer simulation of water-rock systems at a temperature of 25-150°C and under a pressure of up to 600 bar has been carried out for quantitative description of the mineralization formation conditions at sandstone- and shale-hosted copper deposits. The simulation is based on geological and geochemical information concerning the Zhezqazghan deposit and considers (i) a source of ore matter, (ii) composition of the fluid that transfers ore matter to the ore formation zone, and (iii) factors of ore concentration. It has been shown that extraction of copper from minerals of rocks and its accumulation in aqueous solution are optimal at a high mass ratio of rock to water (R/W > 10), Eh of +200 to -100 mV, and an obligatory content of chloride ions in the aqueous phase. The averaged ore-bearing fluid Cl95SO44//Ca50(Na + K)30Mg19 (eq %), pH ˜ 4, mineralization of up to 400 g/L, is formed by the interaction of red sandstone beds with a sedimentogenic brine (a product of metamorphism of seawater in carbonate rocks enriched in organic matter). The ore concentration proceeds in the course of cooling from 150 to 50°C during filtration of ore-bearing fluid through red sandstone beds in the rock-water system thermodynamically opened with respect to the reductive components.

  15. Precision isotope shift measurements in Ca$^+$ using highly sensitive detection schemes

    CERN Document Server

    Gebert, Florian; Wolf, Fabian; Angstmann, Christopher N; Berengut, Julian C; Schmidt, Piet O

    2015-01-01

    We demonstrate an efficient high-precision optical spectroscopy technique for single trapped ions with non-closed transitions. In a double-shelving technique, the absorption of a single photon is first amplified to several phonons of a normal motional mode shared with a co-trapped cooling ion of a different species, before being further amplified to thousands of fluorescence photons emitted by the cooling ion using the standard electron shelving technique. We employ this extension of the photon recoil spectroscopy technique to perform the first high precision absolute frequency measurement of the $^{2}$D$_{3/2}$ $\\rightarrow$ $^{2}$P$_{1/2}$ transition in $^{40}$Ca$^{+}$, resulting in a transition frequency of $f=346\\, 000\\, 234\\, 867(96)$ kHz. Furthermore, we determine the isotope shift of this transition and the $^{2}$S$_{1/2}$ $\\rightarrow$ $^{2}$P$_{1/2}$ transition for $^{42}$Ca$^{+}$, $^{44}$Ca$^{+}$ and $^{48}$Ca$^{+}$ ions relative to $^{40}$Ca$^{+}$ with an accuracy below 100 kHz. Improved field and ...

  16. Elemental Quantitative Distribution and Statistical Analysis on Cross Section of Stainless Steel Sheet by Laser Ablation Inductively Coupled Plasma Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    Qian-hua LUO; Hai-zhou WANG

    2015-01-01

    An innovative application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) technique in illustrating elemental distributions on stainless steel sheets was presented. The technique proved to be a systematic and accurate ap-proach in producing visual images or maps of elemental distributions at cross-sectional surface of a stainless steel sheet. Two stain-less steel sheets served as research objects: 3 mm×1 300 mm hot-rolled stainless steel plate and 1 mm×1 260 mm cold-rolled plate. The cross-sectional surfaces of the two samples at 1/4 position along the width direction were scanned (raster area-44 mm2 and 11 mm2) with a focused laser beam (wavelength 213 nm, diameter of laser crater 100 μm, and laser power 1.6 mJ) in a laser abla-tion chamber. The laser ablation system was coupled to a quadrupole ICP-MS, which made the detection of ion intensities of27Al+, 44Ca+,47Ti+,55Mn+ and56Fe+ within an area of interest possible. One-dimensional (1D) content line distribution maps and two-dimensional (2D) contour maps for speciifc positions or areas were plotted to indicate the element distribution of a target area with high accuracy. Statistic method was used to analyze the acquired data by calculating median contents, maximum segregation, sta-tistic segregation and content-frequency distribution.

  17. Unambiguous characterization of gunshot residue particles using scanning laser ablation and inductively coupled plasma-mass spectrometry.

    Science.gov (United States)

    Abrego, Zuriñe; Ugarte, Ana; Unceta, Nora; Fernández-Isla, Alberto; Goicolea, M Aranzazu; Barrio, Ramón J

    2012-03-06

    A new method based on scanning laser ablation and inductively coupled plasma-mass spectrometry (LA-ICPMS) for the detection and identification of gunshot residue (GSR) particles from firearms discharges has been developed. Tape lifts were used to collect inorganic residues from skin surfaces. The laser ablation pattern and ICPMS conditions were optimized for the detection of metals present in GSR, such as (121)Sb, (137)Ba, and (208)Pb. Other isotopes ((27)Al, (29)Si, (31)P, (33)S, (35)Cl, (39)K, (44)Ca, (57)Fe, (60)Ni, (63)Cu, (66)Zn, and (118)Sn) were monitored during the ICPMS analyses to obtain additional information to possibly classify the GSR particles as either characteristic of GSR or consistent with GSR. In experiments with real samples, different firearms, calibers, and ammunitions were used. The performed method evaluation confirms that the developed methodology can be used as an alternative to the standard scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) technique, with the significant advantage of drastically reducing the analysis time to less than 66 min.

  18. Chemical composition of wet precipitation in Ibadan, Nigeria

    Directory of Open Access Journals (Sweden)

    P.C. Onianwa

    2002-12-01

    Full Text Available Rainwater samples were collected for four two-weekly periods at nine sampling points in the city of Ibadan, Nigeria, during May-July, 1999, and analysed for pH, sulphate, nitrate, chloride, phosphate, sodium, potassium, calcium, and magnesium. The rainwater was predominantly neutral with pH values ranging between 5.8 and 7.0, and averaging 6.6 plus or minus 0.3. Average concentrations (μeq/L for all the sampling points and sampling periods were: SO42- (46 plus or minus 22, NO3- (1.6 plus or minus 0.3, Cl- (11 plus or minus 13, PO43- (3.2 plus or minus 1.8, Na (11.7 plus or minus 7.9, K (5.6 plus or minus 4.4, Ca (30 plus or minus 26, and Mg (1.2 plus or minus 8.8. Concentrations of the various ions in the rainwater decreased slightly with the progress of the sampling period. The deposition flux (kg km-2 month-1 was estimated as: SO42- (390, NO3- (16.8, Cl- (67.6, PO43- (17.5, Na (46.6, K (37.9, Ca (104, and Mg (21.5.

  19. SN1991bg-like supernovae are a compelling source of most Galactic antimatter

    Science.gov (United States)

    Panther, Fiona H.; Crocker, Roland M.; Seitenzahl, Ivo R.; Ruiter, Ashley J.

    2017-01-01

    The Milky Way Galaxy glows with the soft gamma ray emission resulting from the annihilation of ~5 × 1043 electron-positron pairs every second. The origin of this vast quantity of antimatter and the peculiar morphology of the 511keV gamma ray line resulting from this annihilation have been the subject of debate for almost half a century. Most obvious positron sources are associated with star forming regions and cannot explain the rate of positron annihilation in the Galactic bulge, which last saw star formation some 10 Gyr ago, or else violate stringent constraints on the positron injection energy. Radioactive decay of elements formed in core collapse supernovae (CCSNe) and normal Type Ia supernovae (SNe Ia) could supply positrons matching the injection energy constraints but the distribution of such potential sources does not replicate the required morphology. We show that a single class of peculiar thermonuclear supernova - SN1991bg-like supernovae (SNe 91bg) - can supply the number and distribution of positrons we see annihilating in the Galaxy through the decay of 44Ti synthesised in these events. Such 44Ti production simultaneously addresses the observed abundance of 44Ca, the 44Ti decay product, in solar system material.

  20. Calcium isotope fractionation between aqueous compounds relevant to low-temperature geochemistry, biology and medicine

    Science.gov (United States)

    Moynier, Frédéric; Fujii, Toshiyuki

    2017-01-01

    Stable Ca isotopes are fractionated between bones, urine and blood of animals and between soils, roots and leaves of plants by >1000 ppm for the 44Ca/40Ca ratio. These isotopic variations have important implications to understand Ca transport and fluxes in living organisms; however, the mechanisms of isotopic fractionation are unclear. Here we present ab initio calculations for the isotopic fractionation between various aqueous species of Ca and show that this fractionation can be up to 3000 ppm. We show that the Ca isotopic fractionation between soil solutions and plant roots can be explained by the difference of isotopic fractionation between the different first shell hydration degree of Ca2+ and that the isotopic fractionation between roots and leaves is controlled by the precipitation of Ca-oxalates. The isotopic fractionation between blood and urine is due to the complexation of heavy Ca with citrate and oxalates in urine. Calculations are presented for additional Ca species that may be useful to interpret future Ca isotopic measurements. PMID:28276502

  1. Nuclear Structure aspects of gamma decay from giant resonances

    Directory of Open Access Journals (Sweden)

    Bracco A.

    2014-01-01

    Full Text Available The gamma decay of the giant dipole resonance (including its tail region is an important tool to probe the properties of these states, and thus to test the predictions of mean field theories. This paper focuses on two main aspects concerning the electric dipole excitation in nuclei. These are the study of the isospin character of the low energy tail of the Giant Dipole Resonance (GDR, the so-called Pygmy resonance, and the isospin mixing of nuclear systems at finite temperature. In the first case, the Pygmy resonance has been populated in the inelastic scattering reaction 17O+124Sn at 20 MeV/u. Its gamma decay has been measured using the AGATA Demonstrator and an array of 8 large volume LaBr3:Ce scintillators. In the second case, the gamma decay of the GDR in thermalized nuclear systems, formed in fusion evaporation reactions, has been used to investigate the isospin mixing in 80Zr. For this work the reactions 40Ca+40Ca at 3.4 MeV/u and 37Cl +44Ca at 2.6 MeV/u were used.

  2. On-line ion chemistry for the AMS analysis of {sup 90}Sr and {sup 135,137}Cs

    Energy Technology Data Exchange (ETDEWEB)

    Eliades, J. [IsoTrace Laboratory, University of Toronto, 60 St. George St., Toronto, ON, M5S 1A7 (Canada); Zhao, X.-L. [Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, K1N 6N5 (Canada); Litherland, A.E. [IsoTrace Laboratory, University of Toronto, 60 St. George St., Toronto, ON, M5S 1A7 (Canada); Kieser, W.E., E-mail: liam.kieser@utoronto.ca [Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, K1N 6N5 (Canada)

    2013-01-15

    The analysis of {sup 90}Sr by AMS has so far required the use of very large tandem accelerators in order to separate the isobar {sup 90}Zr by the rate-of-energy-loss method. The analysis of {sup 135,137}Cs by AMS has never been attempted as the separation of the isobars {sup 135,137}Ba by the traditional method requires even higher energies, so that this approach would become prohibitively expensive for routine analysis. Following the successful demonstration of Cl{sup -}-S{sup -} separation by the Isobar Separator, the same apparatus was used to test the separation of other pairs of isobars. Surprisingly effective results were obtained with NO{sub 2} gas in the cases of SrF{sub 3}{sup -}-ZrF{sub 3}{sup -} and CsF{sub 2}{sup -}-BaF{sub 2}{sup -} separations. Reduction factors of {approx}4 Multiplication-Sign 10{sup -6} for ZrF{sub 3}{sup -}/SrF{sub 3}{sup -} and {approx}2 Multiplication-Sign 10{sup -5} for BaF{sub 2}{sup -}/CsF{sub 2}{sup -} were measured. SrF{sub 3}{sup -} and CsF{sub 2}{sup -} are both super-halogen anions and are preferentially produced in the ion source rather than ZrF{sub 3}{sup -} and BaF{sub 2}{sup -} when using the PbF{sub 2} matrix-assisted method. Reduction factors for ion source production with such targets of {approx}3 Multiplication-Sign 10{sup -5} for ZrF{sub 3}{sup -}-SrF{sub 3}{sup -} and {approx}5 Multiplication-Sign 10{sup -4} for BaF{sub 2}{sup -}-CsF{sub 2}{sup -} were found. The combined methods would suggest a theoretical detection sensitivity for {sup 90}Sr/Sr {approx}6 Multiplication-Sign 10{sup -16}, {sup 135}Cs/Cs {approx}7 Multiplication-Sign 10{sup -15} and {sup 137}Cs/Cs {approx}1 Multiplication-Sign 10{sup -14}, assuming 10 ppm Zr and Ba contamination in the AMS targets. In addition to the earlier Cl{sup -}-S{sup -} separation work, these measurements further illustrate the potential of on-line ion chemical methods for broadening the analytical scope of small AMS systems.

  3. {sup 90}Nb - a potential PET nuclide. Production and labeling of monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Radchenko, V.; Roesch, F. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Hauser, H.; Eisenhut, M. [German Cancer Research Center, Heidelberg (Germany). Radiopharmaceutical Chemistry; Vugts, D.J.; Dongen, G.A.M.S. van [VU University Medical Center, Amsterdam (Netherlands). Dept. of Nuclear Medicine and PET Research; VU University Medical Center, Amsterdam (Netherlands). Dept. of Otolaryngology/Head and Neck Surgery

    2012-07-01

    Fast progressing immuno-PET gives reasons to develop new potential medium-long and long-lived radioisotopes. One of the promising candidates is {sup 90}Nb. It has a half-life of 14.6 h, which allows visualizing and quantifying processes with medium and slow kinetics, such as tumor accumulation of antibodies and antibodies fragments or polymers and other nanoparticles. {sup 90}Nb exhibits a high positron branching of 53% and an optimal energy of {beta}{sup +} emission of E{sub mean} = 0.35 MeV only. Consequently, efficient radionuclide production routes and Nb{sup V} labeling techniques are required. {sup 90}Nb was produced by the {sup 90}Zr(p,n){sup 90}Nb nuclear reaction on natural zirconium targets. No-carrier-added (n.c.a.) {sup 90}Nb was separated from the zirconium target via a multi-step separation procedure including extraction steps and ion-exchange chromatography. Protein labeling was exemplified using the bifunctional chelator desferrioxamine attached to the monoclonal antibody rituximab. Desferrioxamine was coupled to rituximab via two different routes, by the use of N-succinyl-desferrioxamine (N-suc-Df) and by means of the bifunctional derivative p-isothiocyanatobenzyl-desferrioxamine B (Df-Bz-NCS), respectively. Following antibody modification, labeling with {sup 90}Nb was performed in HEPES buffer at pH 7 at room temperature. In vitro stability of the radiolabeled conjugates was tested in saline buffer at room temperature and in fetal calf serum (FCS) at 37 C. The selected production route led to a high yield of 145 {+-} 10 MBq/{mu}A h of {sup 90}Nb with high radioisotopic purity of > 97%. This yield may allow for large scale production of about 10 GBq {sup 90}Nb. The separation procedure resulted in 76-81% yield. The Zr/{sup 90}Nb decontamination factor reaches 10{sup 7}. Subsequent radiolabeling of the two different conjugates with {sup 90}Nb gave high yields; after one hour incubation at room temperature, more than 90% of {sup 90}Nb-Df-mAb was

  4. First identification of the 0{sub 2}{sup +} state in {sup 30}Mg via its E0 transition

    Energy Technology Data Exchange (ETDEWEB)

    Schwerdtfeger, Wolfgang Norbert Erik

    2008-08-28

    The known 1789 keV level in {sup 30}Mg turned out to be a candidate for the 0{sub 2}{sup +} state due to its long lifetime of 3.9(4) ns and the absence of a {gamma} transition to the ground state. This triggered our search on the 0{sub 2}{sup +}{yields}0{sub 1}{sup +} E0 transition in {sup 30}Mg following the {beta} decay of {sup 30}Na: {beta} decay electrons were detected in a scintillation detector, while conversion electrons were focused onto a cooled Si(Li) detector using a Mini-Orange and detected with high resolution, which simultaneously suppresses the high background of {beta} decay electrons. Due to the large Q value of the {beta} decay of {sup 30}Na (17.3 MeV) the suppression of the coincident background induced by high-energy {gamma} rays and subsequently Compton-scattered electrons turned out to be the key challenge for the success of this experiment. In order to optimise the background suppression and thus the sensitivity to weak E0 transitions, offline test measurements using an {sup 90}Y and a {sup 152}Eu source were performed together with GEANT4 simulations. Resulting from these test measurements a highly sensitive experimental setup was designed and built, consequently minimising the amount of high-Z material in the target chamber, reducing X-ray production. As a by-product from test measurements the database value of the half-life of the 0{sub 2}{sup +} state in {sup 90}Zr could be corrected by more than 30 % to be t{sub 1/2}=41(1) ns. Finally, in a {beta} decay experiment at the ISOLDE facility at CERN the 0{sub 2}{sup +}{yields}0{sub 1}{sup +} E0 transition in {sup 30}Mg could be identified at the expected transition energy of 1788 keV proving for the first time shape coexistence at the borderline of the 'Island of Inversion'. This identification allows to determine the electric monopole strength as {rho}{sup 2}(E0)=26.2(7.5) x 10{sup -3}, indicating a rather weak mixing between the states in two potential minima in a simplified two

  5. Image-based dosimetry for selective internal radiation therapy (SIRT) using yttrium-90 microspheres

    Science.gov (United States)

    Selwyn, Reed G.

    90Y-loaded microspheres are currently used as a palliative treatment for patients with primary and metastatic solid liver tumors. These microspheres contain radioactive 90Y, which decays via beta-minus transition to 90Zr. While the normal liver receives about 75% of its blood supply from the portal vein, hepatic tumors receive their blood supply almost exclusively from the hepatic artery. Taking advantage of this unique blood flow, radioactive microspheres are injected into the hepatic artery resulting in a preferential distribution to tumor sites within the liver. Studies show that the single best prognostic indicator for patient response is the tumor-to-normal tissue (T:N) activity uptake ratio. However, 90Y emits very few photons its broad bremsstrahlung spectrum leads to diffuse, low resolution images, which are insufficient for accurate T:N quantification. Thus, the first objective was to develop a PET-labeled microsphere as a surrogate for the therapeutic microsphere to provide accurate biodistribution information. Furthermore, patient outcome is also suspected to be linked to the mean tumor dose and tumor dose volume histogram. Therefore, a second objective was to develop and validate a method to calculate the dose distribution within the tumor and normal liver tissue. Computer software that generates three-dimensional (3D) dose distributions was validated by comparing results to experimental measurements. The novel development of a 3D gel dosimeter will be discussed as well as a new protocol for 2D film dosimetry. Both dosimetry methods were validated but only film provided the desired accuracy. The overall accuracy of the dose distribution depends on the uncertainty of the 90Y assay, which can extend to 15% at 1sigma. Therefore, the third objective was to develop an accurate non-destructive assay of 90Y. To this end, a new 90Y positron branching ratio was measured and a clinically relevant transfer standard was developed. In summation, this thesis will

  6. 聚变-裂变混合堆水冷包层中子物理性能研究

    Institute of Scientific and Technical Information of China (English)

    徐红; 杨永伟; 周志伟

    2009-01-01

    研究直接应用国际热核聚变实验堆(ITER)规模的聚变堆作为中子驱动源,采用天然铀为初装核燃料,并采用现有压水堆核电厂成熟的轻水慢化和冷却技术,设计聚变-裂变混合堆裂变及产氚包层的技术可行性。应用MCNP与Origen2相耦合的程序进行计算分析,研究不同核燃料对包层有效增殖系数、氚增殖比、能量放大系数和外中子源效率等中子物理性能的影响。计算分析结果显示,现有核电厂广泛使用的UO2核燃料以及下一代裂变堆推荐采用的UC、UN和U90 Zr10等高性能陶瓷及合金核燃料作为水冷包层的核燃料,都能满足以产能发电为设计目标的新型聚变-裂变混合堆能量放大倍数的设计要求,但只有U90和Zr10燃料同时满足聚变燃料氚的生产与消耗自持的要求。研究结果对进一步研发满足未来核能可持续发展的新型聚变一裂变混合堆技术具有潜在参考价值。

  7. Zirconium isotope constraints on the composition of Theia and current Moon-forming theories

    Science.gov (United States)

    Akram, W.; Schönbächler, M.

    2016-09-01

    The giant impact theory is the most widely recognized formation scenario of the Earth's Moon. Giant impact models based on dynamical simulations predict that the Moon acquired a significant amount of impactor (Theia) material, which is challenging to reconcile with geochemical data for O, Si, Cr, Ti and W isotopes in the Earth and Moon. Three new giant impact scenarios have been proposed to account for this discrepancy - hit-and-run impact, impact with a fast-spinning protoEarth and massive impactors - each one reducing the proportion of the impactor in the Moon compared to the original canonical giant impact model. The validity of each theory and their different dynamical varieties are evaluated here using an integrated approach that considers new high-precision Zr isotope measurements of lunar rocks, and quantitative geochemical modelling of the isotopic composition of the impactor Theia. All analysed lunar samples (whole-rock, ilmenite and pyroxene separates) display identical Zr isotope compositions to that of the Earth within the uncertainty of 13 ppm for 96Zr/90Zr (2σ weighted average). This 13 ppm upper limit is used to infer the most extreme isotopic composition that Theia could have possessed, relative to the Earth, for each of the proposed giant impact theories. The calculated Theian composition is compared with the Zr isotope compositions of different solar system materials in order to constrain the source region of the impactor. As a first order approximation, we show that all considered models (including the canonical) are plausible, alleviating the initial requirement for the new giant impact models. Albeit, the canonical and hit-and-run models are the most restrictive, suggesting that the impactor originated from a region close to the Earth. The fast-spinning protoEarth and massive impactor models are more relaxed and increase the allowed impactor distance from the Earth. Similar calculations carried out for O, Cr, Ti and Si isotope data support

  8. Radioembolization and the dynamic role of 90Y PET/CT

    Directory of Open Access Journals (Sweden)

    Alexander S Pasciak

    2014-02-01

    Full Text Available Before the advent of tomographic imaging, it was postulated that decay of 90Y to the 0+ excited state of 90Zr may result in emission of a positron-electron pair. While the branching ratio for pair production is small (~32x10-6, PET has been successfully used to image 90Y in numerous recent patient and phantom studies. 90Y PET imaging has been performed on a variety of PET/CT systems, with and without time-of-flight (TOF and/or resolution recovery capabilities as well as on both BGO and L(YSO based scanners. On all systems, resolution and contrast superior to bremsstrahlung SPECT has been reported. The intrinsic radioactivity present in L(YSO-based PET scanners is a potential limitation associated with accurate quantification of 90Y. However, intrinsic radioactivity has been shown to have a negligible effect at the high activity concentrations common in 90Y radioembolization. Accurate quantification is possible on a variety of PET scanner models, with or without TOF, although TOF improves accuracy at lower activity concentrations. Quantitative 90Y PET images can be transformed into 3D maps of absorbed dose based on the premise that the 90Y activity distribution does not change after infusion. This transformation has been accomplished primarily with the use of 3D dose point-kernel convolution. From a clinical standpoint, 90Y PET provides a superior post-infusion evaluation of treatment technical success owing to its improved resolution. Absorbed dose maps generated from quantitative PET data can be used to predict treatment efficacy and manage patient follow-up. For patients who receive multiple treatments, this information can also be used to provide patient-specific treatment planning for successive therapies, potentially improving response. The broad utilization of 90Y PET has the potential to provide a wealth of dose-response information, which may lead to development of improved radioembolization treatment-planning models in the future.

  9. 5-Hydroxy-tryptophan for the treatment of L-DOPA-induced dyskinesia in the rat Parkinson's disease model.

    Science.gov (United States)

    Tronci, Elisabetta; Lisci, Carlo; Stancampiano, Roberto; Fidalgo, Camino; Collu, Maria; Devoto, Paola; Carta, Manolo

    2013-12-01

    The serotonin system has recently emerged as an important player in the appearance of L-DOPA-induced dyskinesia (LID) in experimental models of Parkinson's disease, as it provides an unregulated source of L-DOPA-derived dopamine release in the dopamine-depleted striatum. Accordingly, toxin lesion or pharmacological silencing of serotonin neurons suppressed LID in the rat and monkey models of Parkinson's disease. However, 5-HT1 receptor agonists were also found to partially reduce the therapeutic effect of L-DOPA. In this study, we evaluated whether enhancement of the serotonin tone induced by the administration of the serotonin precursor 5-hydroxy-tryptophan (5-HTP) could affect induction and expression of LID, as well as the therapeutic effect of L-DOPA, in 6-OHDA-lesioned rats. Drug naïve and L-DOPA-primed 6-OHDA-lesioned rats were chronically treated with a daily injection of L-DOPA (6 mg/kg plus benserazide, s.c.) alone, or in combination with 5-HTP (24-48 mg/kg, i.p.). The abnormal involuntary movements (AIMs) test, as well as the stepping and the motor activity tests, were performed during the chronic treatments. Results showed that 5-HTP reduced the appearance of LID of about 50% at both tested doses. A partial reduction of the therapeutic effect of L-DOPA was seen with the higher but not with the lower dose of 5-HTP. 5-HTP 24 mg/kg was also able to reduce the expression of dyskinesia in L-DOPA-primed dyskinetic rats, to a similar extent than in L-DOPA-primed rats. Importantly, the antidyskinetic effect of 5-HTP 24 mg/kg does not appear to be due to a competition with L-DOPA for crossing the blood-brain barrier; in fact, similar L-DOPA striatal levels were found in L-DOPA only and L-DOPA plus 5-HTP 24 mg/kg treated animals. These data further confirm the involvement of the serotonin system in the appearance of LID, and suggest that 5-HTP may be useful to counteract the appearance of dyskinesia in Parkinson's disease patients.

  10. Clinically meaningful treatment responses after switching to galantamine and with addition of memantine in patients with Alzheimer’s disease receiving donepezil

    Directory of Open Access Journals (Sweden)

    Kano O

    2013-02-01

    Full Text Available Osamu Kano,1 Hirono Ito,1 Takanori Takazawa,1 Yuji Kawase,1 Kiyoko Murata,1 Konosuke Iwamoto,1 Tetsuro Nagaoka,1 Takehisa Hirayama,1 Ken Miura,1 Riya Nagata,1 Tetsuhito Kiyozuka,2 Jo Aoyagi,2 Ryuta Sato,2 Teruo Eguchi,3 Ken Ikeda,1 Yasuo Iwasaki11Department of Neurology, Toho University Omori Medical Center, 2Department of Neurology, Federation of National Public Service Personnel Mutual Aid Associations Mishuku Hospital, 3Sakura-kai Medical Group, Tokyo, JapanAbstract: Clinical trials have shown the benefits of acetylcholinesterase inhibitors, such as donepezil and galantamine, and an N-methyl-d-aspartate receptor antagonist, memantine, in patients with Alzheimer’s disease (AD. However, little is known regarding the effects of switching from donepezil 5 mg/day to galantamine 16 or 24 mg/day, or regarding the effects of adding memantine to established therapy compared with increasing the dose of donepezil. This report discusses two studies conducted to evaluate treatment with galantamine and memantine with respect to cognitive benefits and caregiver evaluations in patients with AD receiving donepezil 5 mg/day for more than 6 months. Patients with mild or moderate AD (scores 10–22 on the Mini-Mental State Examination were enrolled in the Galantamine Switch study and switched to galantamine (maximum doses 16 mg versus 24 mg. Patients with moderate to severe AD (Mini-Mental State Examination scores 3–14 were enrolled in the Donepezil Increase versus Additional Memantine study and either had their donepezil dose increased to 10 mg/day or memantine 20 mg/day added to their existing donepezil dose. Patients received the study treatment for 28 weeks and their Disability Assessment for Dementia, Mental Function Impairment Scale, Cohen-Mansfield Agitation Inventory, and Neuropsychiatric Inventory scores were assessed with assistance from their caregivers. For the Galantamine Switch study after 8 weeks, agitation evaluated by the Cohen

  11. Early biomarkers of doxorubicin-induced heart injury in a mouse model

    Energy Technology Data Exchange (ETDEWEB)

    Desai, Varsha G., E-mail: varsha.desai@fda.hhs.gov [Personalized Medicine Branch, Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Kwekel, Joshua C.; Vijay, Vikrant; Moland, Carrie L. [Personalized Medicine Branch, Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Herman, Eugene H. [Toxicology and Pharmacology Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, The National Cancer Institute, 9609 Medical Center Drive, Rockville, MD 20850-9734 (United States); Lee, Taewon [Department of Mathematics, Korea University, Sejong, Chungnam 339-700 (Korea, Republic of); Han, Tao [Personalized Medicine Branch, Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Lewis, Sherry M. [Office of Scientific Coordination, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Davis, Kelly J.; Muskhelishvili, Levan [Toxicologic Pathology Associates, National Center for Toxicological Research, Jefferson, AR 72079 (United States); Kerr, Susan [Arkansas Heart Hospital, Little Rock, AR 72211 (United States); Fuscoe, James C. [Personalized Medicine Branch, Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States)

    2014-12-01

    Cardiac troponins, which are used as myocardial injury markers, are released in plasma only after tissue damage has occurred. Therefore, there is a need for identification of biomarkers of earlier events in cardiac injury to limit the extent of damage. To accomplish this, expression profiling of 1179 unique microRNAs (miRNAs) was performed in a chronic cardiotoxicity mouse model developed in our laboratory. Male B6C3F{sub 1} mice were injected intravenously with 3 mg/kg doxorubicin (DOX; an anti-cancer drug), or saline once a week for 2, 3, 4, 6, and 8 weeks, resulting in cumulative DOX doses of 6, 9, 12, 18, and 24 mg/kg, respectively. Mice were euthanized a week after the last dose. Cardiac injury was evidenced in mice exposed to 18 mg/kg and higher cumulative DOX dose whereas examination of hearts by light microscopy revealed cardiac lesions at 24 mg/kg DOX. Also, 24 miRNAs were differentially expressed in mouse hearts, with the expression of 1, 1, 2, 8, and 21 miRNAs altered at 6, 9, 12, 18, and 24 mg/kg DOX, respectively. A pro-apoptotic miR-34a was the only miRNA that was up-regulated at all cumulative DOX doses and showed a significant dose-related response. Up-regulation of miR-34a at 6 mg/kg DOX may suggest apoptosis as an early molecular change in the hearts of DOX-treated mice. At 12 mg/kg DOX, up-regulation of miR-34a was associated with down-regulation of hypertrophy-related miR-150; changes observed before cardiac injury. These findings may lead to the development of biomarkers of earlier events in DOX-induced cardiotoxicity that occur before the release of cardiac troponins. - Highlights: • Upregulation of miR-34a before doxorubicin-induced cardiac tissue injury • Apoptosis might be an early event in mouse heart during doxorubicin treatment. • Expression of miR-150 declined before doxorubicin-induced cardiac tissue injury.

  12. Effects of Dietary Octacosanol on Growth Performance, Carcass Characteristics and Meat Quality of Broiler Chicks

    Directory of Open Access Journals (Sweden)

    L. Long

    2016-10-01

    Full Text Available Octacosanol, which has prominent physiological activities and functions, has been recognized as a potential growth promoter in animals. A total of 392 1-d-old male Arbor Acres broiler chicks with similar body weight were randomly distributed into four dietary groups of seven replicates with 14 birds each supplemented with 0, 12, 24, or 36 mg octacosanol (extracted from rice bran, purity >92%/kg feed. The feeding trial lasted for six weeks and was divided into the starter (day 1 to 21 and the grower (day 22 to 42 phases. The results showed that the feed conversion ratio (FCR was significantly improved in broilers fed a diet containing 24 mg/kg octacosanol compared with those fed the control diet in the overall phase (day 1 to 42, p = 0.042. The average daily gain and FCR both showed linear effects in response to dietary supplementation of octacosanol during the overall phase (p = 0.031 and 0.018, respectively. Broilers fed with 24 or 36 mg/kg octacosanol diet showed a higher eviscerated yield, which increased by 5.88% and 4.26% respectively, than those fed the control diet (p = 0.030. The breast muscle yield of broilers fed with 24 mg/kg octacosanol diet increased significantly by 12.15% compared with those fed the control diet (p = 0.047. Eviscerated and breast muscle yield increased linearly with the increase in dietary octacosanol supplementation (p = 0.013 and 0.021, respectively. Broilers fed with 24 or 36 mg/kg octacosanol diet had a greater (p = 0.021 pH45min value in the breast muscle, which was maintained linearly in response to dietary octacosanol supplementation (p = 0.003. There was a significant decrease (p = 0.007 in drip loss value between the octacosanol-added and the control groups. The drip loss showed linear (p = 0.004 and quadratic (p = 0.041 responses with dietary supplementation of octacosanol. These studies indicate that octacosanol is a potentially effective and safe feed additive which may improve feed efficiency and meat

  13. A porcine model of progressive Parkinson disease established by chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication

    DEFF Research Database (Denmark)

    Nielsen, M S; Glud, Andreas Nørgaard; Møller, Arne

    2009-01-01

    Parkinson disease (PD) is a common neurodegenerative disorder, resulting from a progressive dopaminergic neurons loss in the substantia nigra (SN). Attempts to discover effective compounds halting PD progression have so far failed in clinical trials, perhaps because current animal models do...... velocity for the intoxicated animals. This decrease could be reversed completely with apomorphine. For dosages of 2-12 mg MPTP/day, the symptoms failed to progress from the initial state of mild Parkinsonism, and some recovery was observed. Animals receiving 18 mg/day progressed to moderate parkinsonism...... analysis revealed steadily decreasing neuronal counts in the SN from 80,700 unilaterally in normal animals to 32,000, 27,000 and 18,000 at 12, 18 and 24 mg/day, respectively. We conclude that it is possible to induce progressive Parkinson disease based on chronic MPTP-intoxication in Göttingen minipigs...

  14. Distribution and variation of arsenic in Wisconsin surface soils, with data on other trace elements

    Science.gov (United States)

    Stensvold, Krista A.

    2012-01-01

    A total of 664 soil samples distributed among different geographic regions and soil types were collected across Wisconsin to describe the distribution of arsenic relative to parent material, soil texture, and drainage class. Soils from 6 inches in depth were composited, digested in aqua regia, and analyzed for 17 trace elements. Observed soil arsenic concentrations range from a high of 39 milligrams per kilogram (mg/kg) to less than the laboratory detection limit of 1 mg/kg. Ten samples with soil arsenic concentrations greater than 8.5 mg/kg were determined to be significantly separate from the main cluster of the dataset. With these outliers removed, overall soil arsenic concentrations in Wisconsin have a median value of 1.8 mg/kg, and the 95-percent upper confidence limit of the mean is 2.4 mg/kg.

  15. A compact source for bunches of singly charged atomic ions

    Science.gov (United States)

    Murböck, T.; Schmidt, S.; Andelkovic, Z.; Birkl, G.; Nörtershäuser, W.; Vogel, M.

    2016-04-01

    We have built, operated, and characterized a compact ion source for low-energy bunches of singly charged atomic ions in a vacuum beam line. It is based on atomic evaporation from an electrically heated oven and ionization by electron impact from a heated filament inside a grid-based ionization volume. An adjacent electrode arrangement is used for ion extraction and focusing by applying positive high-voltage pulses to the grid. The method is particularly suited for experimental environments which require low electromagnetic noise. It has proven simple yet reliable and has been used to produce μs-bunches of up to 106 Mg+ ions at a repetition rate of 1 Hz. We present the concept, setup and characterizing measurements. The instrument has been operated in the framework of the SpecTrap experiment at the HITRAP facility at GSI/FAIR to provide Mg+ ions for sympathetic cooling of highly charged ions by laser-cooled 24Mg+.

  16. Increased isobutanol production in Saccharomyces cerevisiae by overexpression of genes in valine metabolism

    DEFF Research Database (Denmark)

    Chen, Xiao; Nielsen, Kristian Fog; Borodina, Irina;

    2011-01-01

    of its relative tolerance to alcohols, robustness in industrial fermentations, and the possibility for future combination of isobutanol production with fermentation of lignocellulosic materials. RESULTS: The yield of isobutanol was improved from 0.16 to 0.97 mg per g glucose by simultaneous...... overexpression of biosynthetic genes ILV2, ILV3, and ILV5 in valine metabolism in anaerobic fermentation of glucose in mineral medium in S. cerevisiae. Isobutanol yield was further improved by twofold by the additional overexpression of BAT2, encoding the cytoplasmic branched-chain amino-acid aminotransferase...... were 3.86 and 0.28 mg per g glucose, respectively. They increased to 4.12 and 2.4 mg per g glucose in yeast extract/peptone/dextrose (YPD) complex medium under aerobic conditions, respectively. CONCLUSIONS: Overexpression of genes ILV2, ILV3, ILV5, and BAT2 in valine metabolism led to an increase...

  17. Early intravenous ibuprofen decreases narcotic requirement and length of stay after traumatic rib fracture.

    Science.gov (United States)

    Bayouth, Lilly; Safcsak, Karen; Cheatham, Michael L; Smith, Chadwick P; Birrer, Kara L; Promes, John T

    2013-11-01

    Pain control after traumatic rib fracture is essential to avoid respiratory complications and prolonged hospitalization. Narcotics are commonly used, but adjunctive medications such as nonsteroidal anti-inflammatory drugs may be beneficial. Twenty-one patients with traumatic rib fractures treated with both narcotics and intravenous ibuprofen (IVIb) (Treatment) were retrospectively compared with 21 age- and rib fracture-matched patients who received narcotics alone (Control). Pain medication requirements over the first 7 hospital days were evaluated. Mean daily IVIb dose was 2070 ± 880 mg. Daily intravenous morphine-equivalent requirement was 19 ± 16 vs 32 ± 24 mg (P pain scores were lower in the Treatment group (P rib fractures significantly decreases narcotic requirement and results in clinically significant decreases in hospital length of stay. IVIb therapy should be initiated in patients with traumatic rib fractures to improve patient comfort and reduce narcotic requirement.

  18. Existence of six-$\\alpha$ linear structure

    CERN Document Server

    Iwata, Yoritaka; Itagaki, Naoyuki; Maruhn, Joachim A; Otsuka, Takaharu

    2014-01-01

    The stable existence of a six-$\\alpha$ linear structure in highly excited states of $^{24}$Mg is studied based on a systematic Cranked Hartree-Fock calculation with various Skyrme-type interactions. Its stability is examined by allowing the transition of the cluster structure to the shell-model like structure. Especially, the six-$\\alpha$ linear state is exposed to two major instabilities: the bending motion, which is the main path for the transition to low-lying states, and the spin-orbit interaction, which is the driving force to break the $\\alpha$ clusters and enhance the independent motion of the nucleons. The linear structure with large angular momentum is obtained as a meta-stable stationary state.

  19. 液相臭氧氧化法测定海水化学耗氧量%Determination of Chemical Oxygen Demand in Seawater Based on the Technique of Aqueous-Phase Ozone Oxidation

    Institute of Scientific and Technical Information of China (English)

    靳保辉; 庄峙厦; 王小如; Frank S.C.Lee

    2005-01-01

    基于溶解臭氧在水体中能够氧化鲁米诺产生发光现象,建立了一种利用流动注射液相化学发光技术(FI-CL)测定化学耗氧量(COD)的新方法.COD测定范围在0.6~24mg/L之间,适合海水监测.对实际海水水样的测定结果与碱性高锰酸钾法具有一致趋势,测定的相对标准偏差小于10%.

  20. Angular momentum projection for a Nilsson mean-field plus pairing model

    Science.gov (United States)

    Wang, Yin; Pan, Feng; Launey, Kristina D.; Luo, Yan-An; Draayer, J. P.

    2016-06-01

    The angular momentum projection for the axially deformed Nilsson mean-field plus a modified standard pairing (MSP) or the nearest-level pairing (NLP) model is proposed. Both the exact projection, in which all intrinsic states are taken into consideration, and the approximate projection, in which only intrinsic states with K = 0 are taken in the projection, are considered. The analysis shows that the approximate projection with only K = 0 intrinsic states seems reasonable, of which the configuration subspace considered is greatly reduced. As simple examples for the model application, low-lying spectra and electromagnetic properties of 18O and 18Ne are described by using both the exact and approximate angular momentum projection of the MSP or the NLP, while those of 20Ne and 24Mg are described by using the approximate angular momentum projection of the MSP or NLP.

  1. A Combined System for Biological Removal of Nitrogen and Carbon from Nylon-6 Production Wastewater

    Institute of Scientific and Technical Information of China (English)

    LIU Fang; LIU Guo-hua; TIAN Qing; ZHANG Man; CHEN Ji-hua

    2007-01-01

    A combined system consisting of hydrolysisacidification, denitrification and nitrification reactors wasused to remove carbon and nitrogen from the nylon - 6production wastewater, which was characterized by goodbiodegradability and high nitrogen concentration. Theinfluences of Chemical Oxygen Demand(COD) in theinfluent, recirculation ratio, Hydraulic Residence Time(HRT) and Dissolved Oxygen(DO) concentration on thesystem performances were investigated. From results itcould be seen that good performances have been achievedduring the overall experiments periods, and COD, TotalNitrogen(TN), NH+-N and Suspended Solids(SS) in theeffluent were 53, 16, 2 and 24 mg·L-1, respectively,which has satisfied the first standard of wastewaterdischarge established by Environmental Protection Agency(EPA) of China. Furthermore, results showed thatoperation factors, viz. COD in the influent, recirculationratio, HRT and DO concentration, all had importantinfluences on the system performances.

  2. Three-dimensional angular momentum projection in relativistic mean-field theory

    CERN Document Server

    Yao, J M; Ring, P; Arteaga, D Pena

    2009-01-01

    Based on a relativistic mean-field theory with an effective point coupling between the nucleons, three-dimensional angular momentum projection is implemented for the first time to project out states with designed angular momentum from deformed intrinsic states generated by triaxial quadrupole constraints. The same effective parameter set PC-F1 of the effective interaction is used for deriving the mean field and the collective Hamiltonian. Pairing correlations are taken into account by the BCS method using both monopole forces and zero range d-forces with strength parameters adjusted to experimental even-odd mass differences. The method is applied successfully to the isotopes 24Mg, 30Mg, and 32Mg.

  3. Hybrid magnetic amphiphilic composites based on carbon nanotube/nanofibers and layered silicates fragments as efficient adsorbent for ethynilestradiol.

    Science.gov (United States)

    Purceno, Aluir D; Teixeira, Ana Paula C; de Souza, Nubia Janaína; Fernandez-Outon, Luis E; Ardisson, José D; Lago, Rochel M

    2012-08-01

    In this work, hybrid magnetic amphiphilic composites were prepared by the catalytic growth of carbon nanotubes (CNTs) and nanofibers CNF on layered silicates fragments. SEM, TEM, Raman, XRD, Mössbauer, TG/DTA showed that CVD with CH(4) at 800°C produced CNF and magnetic Fe cores fixed on the surface of microfragments of silicates layers. Due to the amphiphilic character, the composites can be easily dispersed in water and efficiently adsorb hydrophobic contaminant molecules. For example, the composites showed remarkable adsorption capacities for the hormone ethinylestradiol, e.g. 2-4 mg m(-2), compared to ca. 0.1 mg m(-2) obtained for high surface area activated carbon and multiwall CNT. These results are discussed in terms of a high hydrophobic exposed surface area of the CNT and CNF fixed on the layered silicates fragments surface. Moreover, the composites can be easily removed from water by a simple magnetic separation process.

  4. Antibacterial activity of Ocimum gratissimum L. essential oil

    Directory of Open Access Journals (Sweden)

    Celso Vataru Nakamura

    1999-09-01

    Full Text Available The essential oil (EO of Ocimum gratissimum inhibited Staphylococcus aureus at a concentration of 0.75 mg/ml. The minimal inhibitory concentrations (MICs for Shigella flexineri, Salmonella enteritidis, Escherichia coli, Klebsiella sp., and Proteus mirabilis were at concentrations ranging from 3 to 12 mg/ml. The endpoint was not reached for Pseudomonas aeruginosa (>=24 mg/ml. The MICs of the reference drugs used in this study were similar to those presented in other reports. The minimum bactericidal concentration of EO was within a twofold dilution of the MIC for this organism. The compound that showed antibacterial activity in the EO of O. gratissimum was identified as eugenol and structural findings were further supported by gas chromatography/mass spectra retention time data. The structure was supported by spectroscopic methods.

  5. First observation of {gamma}-ray emission assigned to the decay of {sup 164}W

    Energy Technology Data Exchange (ETDEWEB)

    Dressler, R.; Bruchertseifer, H. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Schumann, D. [Technische Univ. Dresden (Germany); Taut, S. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany); Fischer, S. [Humboldt-Universitaet, Berlin (Germany). Bereich Medizin (Charite); Binder, R. [Leipzig Univ. (Germany); Yakushev, A.B.; Buklanov, G.; Lien, D.T.; Domanov, V.P. [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Szeglowski, Z.; Kubica, B. [Henryk Niewodniczanski Inst. of Nuclear Physics, Cracow (Poland); Guseva, L.I.; Tikhomirova, G.S. [Rossijskaya Akademiya Nauk, Moscow (Russian Federation). Inst. Geokhimii i Analiticheskoj Khimii; Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)]|[Bern Univ. (Switzerland)

    1997-12-31

    The excitation functions of the short-lived tungsten isotopes {sup 164}W and {sup 165}W produced in the nuclear reaction {sup 24}Mg + {sup 144}Sm were measured for E{sub Lab} = 109 MeV - 141 MeV. Two {gamma}-lines at (187.0{+-}0.1) keV and (268.7{+-}0.2) keV were discovered in the {gamma}-spectra of the tungsten fraction after chemical separation at a beam energy of 128 MeV which we assign to {sup 164}W. The half-life of the 187.0 keV {gamma}-line is (7.0{+-}0.2) s. (orig.) 14 refs.

  6. The effect of hyperfine interactions on ultracold molecular collisions: NH(^3Sigma^-) with Mg(^1S) in magnetic fields

    CERN Document Server

    González-Martínez, Maykel L

    2011-01-01

    We investigate the effect of hyperfine interactions on ultracold molecular collisions in magnetic fields, using ^{24}Mg(^1S) + ^{14}NH(^3Sigma^-) as a prototype system. We explore the energy and magnetic field dependence of the cross sections, comparing the results with previous calculations that neglected hyperfine interactions (Phys. Rev. Lett. 103, 183201 (2009)). The main effect of hyperfine interactions for spin relaxation cross sections is that the kinetic energy release of the dominant outgoing channels does not reduce to zero at low fields. This results in reduced centrifugal suppression on the cross sections and increased inelastic cross sections at low energy and low field. We also analyze state-to-state cross sections, for various initial states, and show that hyperfine interactions introduce additional mechanisms for spin relaxation. In particular, there are hyperfine-mediated collisions to outgoing channels that are not centrifugally suppressed. However, for Mg+NH these unsuppressed channels make...

  7. CARBOXYLIC ACIDS OF HERB OF THYMUS CRETACEUS KLOK. ET SCHOST

    Directory of Open Access Journals (Sweden)

    V. N. Bubenchikova

    2014-01-01

    Full Text Available We have studied carboxylic acids of the herb of Thymus cretaceus Klok. et Schost which is widespread on a territory of some regions (Belgorod, Voronezh. The study was carried out using gas-liquid chromatography at Agilent Technologies 6890 chromatographer with massspectrometric detector 5973 N. Acids concentration was calculated by means of inner standard.We have established that carboxylic acids of Thymus cretaceus are represented by 34 compounds. Palmitic (1779.02 mg/kg, behenic (1084.15 mg/kg, levulinic (986.24 mg/kg and linoleic acids (678.82 mg/kg predominate among fatty acids; citric (9835.14 mg/kg, malonic (447.91 mg/kg and oxalic acids (388.32 mg/kg predominate among organic acids; andferulic acid predominate amongphenolcarbonic acids.

  8. Inversion doublets of reflection-asymmetric clustering in 28Si and their isoscalar monopole and dipole transitions

    CERN Document Server

    Chiba, Y; Kimura, M

    2016-01-01

    [Background] Various cluster states of astrophysical interest are expected to exist in the excited states of $^{28}{\\rm Si}$. However, they have not been identified firmly, because of the experimental and theoretical difficulties. [Purpose] To establish the $^{24}$Mg+$\\alpha$, $^{16}$O+$^{12}$C and $^{20}$Ne+2$\\alpha$ cluster bands, we theoretically search for the negative-parity cluster bands that are paired with the positive-parity bands to constitute the inversion doublets. We also offer the isoscalar monopole and dipole transitions as a promising probe for the clustering. We numerically show that these transition strengths from the ground state to the cluster states are very enhanced. [Method] The antisymmetrized molecular dynamics with Gogny D1S effective interaction is employed to calculate the excited states of $^{28}{\\rm Si}$. The isoscalar monopole and dipole transition strengths are directly evaluated from wave functions of the ground and excited states. [Results] Negative-parity bands having $^{24}...

  9. Dose-dependent striatal changes in dopaminergic terminals and alpha-synuclein reactivity in a porcine model of progressive Parkinson’s disease

    DEFF Research Database (Denmark)

    Nielsen, Mette Slot; Glud, Andreas Nørgaard; Møller, Arne

    2011-01-01

    Parkinson disease (PD) is a common neurodegenerative disorder, resulting from a progressive dopaminergic neuron loss in the substantia nigra (SN). Alpha-synuclein positive neuronal inclusion bodies and progressive loss of dopaminergic striatal terminals is also well described in PD. Attempts......) or acute MPTP intoxication for 11 days (24 mg MPTP/day, n=2) and 9 weeks of recovery. Four pigs served as normal controls. Animals were euthanized with intracardial pentobarbital injections, transcardially perfused with 5 L 4% paraformaldehyde and the brains removed. The striatae and brain stems including...... the SN were paraffin embedded and immunohistochemically stained for tyrosine hydroxylase (TH) and alpha-synuclein. Stereological examination of the SN showed progressive nigral neuron loss with increased MPTP dosages. Occasional neuronal staining confined to the cytoplasm and cell membrane was observed...

  10. [Conservative treatment of ectopic pregnancy].

    Science.gov (United States)

    Odland, J O; Maltau, J M; Tollan, A

    1991-01-30

    During the last decades the incidence of ectopic pregnancy has been steadily rising. The chosen therapy has usually been unilateral salpingectomy. Recently, different conservative (tube-preserving) treatment-modalities have been introduced in clinical practice. We have tried conservative treatment by local injection of prostaglandin F2a (total dose 2-4 mg) directly into the tubal pregnancy and, if feasible, also into the corpus luteum graviditate. The treatment was successful in 13 out of 16 patients. In one patient laparotomia was performed because of pain, and revealed a haematoma in fossa Douglasi. Reinjection of prostaglandin was necessary in one patient because of rising HCG titres. One patient was hospitalized for four days because of nausea and pain. The treatment was otherwise successful. The method may be useful as a non-surgical alternative in haemodynamically stable patients without tubal rupture. Further studies are needed to evaluate the outcome in terms of future fertility.

  11. Effects of a prolonged administration of valepotriates in rats on the mothers and their offspring.

    Science.gov (United States)

    Tufik, S; Fujita, K; Seabra, M de L; Lobo, L L

    1994-01-01

    Valeriana officinalis L. (Valerianaceae) is widely known to be associated with sedative properties. The effects of a valepotriates mixtures on mothers and progeny were evaluated in rats. A 30-day administration of valepotriates did not change the average length of estral cycle, nor the number of estrous phases during this period. Also, there were no changes on the fertility index. Fetotoxicity and external examination studies did not show differences, although internal examination revealed an increase in number of retarded ossification after the highest doses employed--12 and 24 mg/kg. No changes were detected in the development of the offspring after treatment during pregnancy. As for temperature, valepotriates caused a hypothermizant effect after administration by the intraperitoneal route but not after oral administration. Generally, the valepotriates employed induced some alterations after administration by the intraperitoneal route, but doses given orally were innocuous to pregnant rats and their offspring.

  12. Effects of long-term administration of a cocoa polyphenolic extract (Acticoa powder) on cognitive performances in aged rats.

    Science.gov (United States)

    Bisson, Jean-François; Nejdi, Amine; Rozan, Pascale; Hidalgo, Sophie; Lalonde, Robert; Messaoudi, Michaël

    2008-07-01

    Numerous studies have indicated that increased vulnerability to oxidative stress may be the main factor involved in functional declines during normal and pathological ageing, and that antioxidant agents, such as polyphenols, may improve or prevent these deficits. We examined whether 1-year administration of a cocoa polyphenolic extract (Acticoa powder), orally delivered at the dose of 24 mg/kg per d between 15 and 27 months of age, affects the onset of age-related cognitive deficits, urinary free dopamine levels and lifespan in old Wistar-Unilever rats. Acticoa powder improved cognitive performances in light extinction and water maze paradigms, increased lifespan and preserved high urinary free dopamine levels. These results suggest that Acticoa powder may be beneficial in retarding age-related brain impairments, including cognitive deficits in normal ageing and perhaps neurodegenerative diseases. Further studies are required to elucidate the mechanisms of cocoa polyphenols in neuroprotection and to explore their effects in man.

  13. Proton Spectroscopic Factors Deduced from Helium-3 Global Phenomenological and Microscopic Optical Model Potentials

    Science.gov (United States)

    Jenny, Lee; Pang, Dan-Yang; Han, Yin-Lu; B. Tsang, M.

    2014-09-01

    Global phenomenological GDP08 and microscopic helium-3 optical model potentials have been recently derived. We evaluate these two potential sets by comparing the elastic scattering data of 25 MeV 3He on 16O, 18O, 19F, 23Na, 24Mg, 25Mg, 26Mg, 27Al, 28Si, 30Si, 31P, 32S, 34S, 35Cl, 37Cl, and 39K isotopes. Using the deuteron angular distributions calculated with the distorted wave Born approximation model, we extract the ground-state proton spectroscopic factors from (3He, d) reactions on the same set of nuclei. The extracted proton spectroscopic factors are compared with the large-basis shell-model calculations.

  14. Simultaneous determination of rare earth elements in ore and anti-corrosion coating samples using a portable capillary electrophoresis instrument with contactless conductivity detection.

    Science.gov (United States)

    Nguyen, Thi Anh Huong; Nguyen, Van Ri; Le, Duc Dung; Nguyen, Thi Thanh Binh; Cao, Van Hoang; Nguyen, Thi Kim Dung; Sáiz, Jorge; Hauser, Peter C; Mai, Thanh Duc

    2016-07-29

    The employment of an in-house-made capillary electrophoresis (CE) instrument with capacitively coupled contactless conductivity detection (C(4)D) as a simple and inexpensive solution for simultaneous determination of many rare earth elements (REEs) in ore samples from Vietnam, as well as in anti-corrosion coating samples is reported. 14 REEs (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were determined using an electrolyte composed of 20mM arginine and 10mM α-hydroxyisobutyric acid adjusted to pH 4.2 with acetic acid. The best detection limit achieved was 0.24mg/L using the developed CE-C(4)D method. Good agreement between results from CE-C(4)D and the confirmation method (ICP-MS) was achieved, with a coefficient of determination (r(2)) for the two pairs of data of 0.998.

  15. Corrigendum to "Equilibrium magnesium isotope fractionation between aqueous Mg2+ and carbonate minerals: Insights from path integral molecular dynamics" [Geochim. Cosmochim. Acta 163 (2015) 126-139

    Science.gov (United States)

    Pinilla, Carlos; Blanchard, Marc; Balan, Etienne; Natarajan, Suresh K.; Vuilleumier, Rodolphe; Mauri, Francesco

    2015-10-01

    The theoretical 26Mg/24Mg β-factor of aqueous Mg2+ of Schauble (2011) has been reported with an error in Pinilla et al. (2015). The corresponding value in Table 7 is incorrect and should read 25.5‰ at 298 K. In Section 3.6 (page 133), one sentence is affected and should be rephrased as: "It is noteworthy that the estimate of the Mg(aq)β-factor from a set of salts containing the Mg(H20)62+ complex leads to a value ∼2‰ higher than the other estimates at 298 K." Finally, the curves in Fig. 8 corresponding to the calculations of Schauble (2011) have been corrected in the figure below.

  16. Intoxicação com digoxina

    OpenAIRE

    Neto, Cláudia; Teixeira, Carla; Medeiros, Rosa; Fernandes, Ana Paula

    2014-01-01

    A intoxicação digitálica intencional é um evento raro em idade pediátrica. Tal como nos adultos, doses tóxicas de digoxina podem acarretar arritmias graves e fatais. Apresenta-se o caso de uma adolescente de 14 anos que ingeriu voluntariamente 4,75 mg de digoxina (0,1 mg/kg) e 1,2 g de furosemida (24 mg/kg). Duas horas após a ingestão inicia bradicardia sinusal sustentada sintomática com necessidade de colocação de pacemaker endocavitário provisório. Neste caso, a intoxicação por digoxina e f...

  17. An actively vetoed Clover gamma-detector for nuclear astrophysics at LUNA

    CERN Document Server

    Szucs, T; Broggini, C; Caciolli, A; Confortola, F; Corvisiero, P; Elekes, Z; Formicola, A; Fulop, Zs; Gervino, G; Guglielmetti, A; Gustavino, C; Gyurky, Gy; Imbriani, G; Junker, M; Lemut, A; Marta, M; Mazzocchi, C; Menegazzo, R; Prati, P; Roca, V; Rolfs, C; Alvarez, C Rossi; Somorjai, E; Straniero, O; Strieder, F; Terrasi, F; Trautvetter, H P

    2010-01-01

    An escape-suppressed, composite high-purity germanium detector of the Clover type has been installed at the Laboratory for Underground Nuclear Astrophysics (LUNA) facility, deep underground in the Gran Sasso Laboratory, Italy. The laboratory gamma-ray background of the Clover detector has been studied underground at LUNA and, for comparison, also in an overground laboratory. Spectra have been recorded both for the single segments and for the virtual detector formed by online addition of all four segments. The effect of the escape-suppression shield has been studied as well. Despite their generally higher intrinsic background, escape-suppressed detectors are found to be well suited for underground nuclear astrophysics studies. As an example for the advantage of using a composite detector deep underground, the weak ground state branching of the Ep = 223 keV resonance in the 24Mg(p,gamma)25Al reaction is determined with improved precision.

  18. Citrininotoxinogenicity of Penicillium spp. isolated from decaying apples

    Directory of Open Access Journals (Sweden)

    Pepeljnjak Stjepan

    2002-01-01

    Full Text Available A study on the occurrence of citrinin and citrinin production ability of Penicillium spp. isolated from decaying apples collected from households in Croatia was carried out. Among 100 samples of apples, 37 strains of Penicillium spp. were found, including P. expansum, P. roqueforti, P. implicatum and P. purpurogenum. Citrinin production in liquid yeast medium by 11 strains of P. expansum varied in a range of 0.07 to 9.00 mg.kg-1. Citrinin was isolated from 19% of apple samples in range of 0.05 to 0.24 mg.kg-1. Antimicrobial activity of isolated citrinin, evaluated through tests on Bacillus subtilis, presented inhibitory zones varying from 5 mm to 1 cm. Minimal inhibitory concentrations (MIC were 0.0072 µg.mL-1 for bacteriostatic effect, and 0.0144 µg.mL-1 for bactericidal effect.

  19. Micropropagation of Origanum acutidens (HAND.-MAZZ.) IETSWAART using stem node explants.

    Science.gov (United States)

    Yildirim, Mehmet Ugur

    2013-01-01

    Origanum acutidens (HAND.-MAZZ.) IETSWAART is a promising ornamental plant that can be widely used in landscape management. It is endemic to Eastern Anatolian region of Turkey. Tissue culture has not been used to micropropagate it. The study reports stem node explants from one-week-old seedlings of the plant for successful micropropagation. The stem nodes were cultured on MS medium containing 0.6, 1.2, 1.8, and 2.4 mg/L BAP with 0.2 mg/L NAA. Visible effects of culture media on shoot proliferation were recorded. Shoot regeneration rate was maximum on MS medium containing 1.80 mg/L BAP-0.2 mg/L NAA. The micropropagated shoots were rooted on MS medium containing 0.2 mg/L NAA. All microrooted plantlets survived during acclimatisation on peat moss. It was concluded that O. acutidens can be successfully micropropagated under in vitro conditions.

  20. Cluster formation probability in the trans-tin and trans-lead nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, K.P. [School of Pure and Applied Physics, Kannur University, Payyanur Campus, Payyanur 670 327 (India)], E-mail: drkpsanthosh@gmail.com; Biju, R.K.; Sahadevan, Sabina [P.G. Department of Physics and Research Centre, Payyanur College, Payyanur 670 327 (India)

    2010-07-01

    Within our fission model, the Coulomb and proximity potential model (CPPM) cluster formation probabilities are calculated for different clusters ranging from carbon to silicon for the parents in the trans-tin and trans-lead regions. It is found that in trans-tin region the {sup 12}C, {sup 16}O, {sup 20}Ne and {sup 24}Mg clusters have maximum cluster formation probability and lowest half lives as compared to other clusters. In trans-lead region the {sup 14}C, {sup 18,20}O, {sup 23}F, {sup 24,26}Ne, {sup 28,30}Mg and {sup 34}Si clusters have the maximum cluster formation probability and minimum half life, which show that alpha like clusters are most probable for emission from trans-tin region while non-alpha clusters are probable from trans-lead region. These results stress the role of neutron proton symmetry and asymmetry of daughter nuclei in these two cases.

  1. Cluster formation probability in the trans-tin and trans-lead nuclei

    CERN Document Server

    Santhosh, K P; Sahadevan, Sabina; 10.1016/j.nuclphysa.2010.03.004

    2010-01-01

    Within our fission model, the Coulomb and proximity potential model (CPPM) cluster formation probabilities are calculated for different clusters ranging from carbon to silicon for the parents in the trans-tin and trans- lead regions. It is found that in trans-tin region the 12^C, 16^O, 20^Ne and 24^Mg clusters have maximum cluster formation probability and lowest half lives as compared to other clusters. In trans-lead region the 14^C, 18, 20^O, 23^F, 24,26^Ne, 28,30^Mg and 34^Si clusters have the maximum cluster formation probability and minimum half life, which show that alpha like clusters are most probable for emission from trans-tin region while non-alpha clusters are probable from trans-lead region. These results stress the role of neutron proton symmetry and asymmetry of daughter nuclei in these two cases.

  2. Low plasma concentrations achieved with conventional schedules of administration of ganciclovir in patients with AIDS.

    Science.gov (United States)

    Piketty, C; Bardin, C; Gilquin, J; Mahe, V; Kazatchkine, M D; Chast, F

    1996-07-01

    Plasma concentration of ganciclovir was studied prospectively in 15 AIDS patients treated for acute cytomegalovirus (CMV) retinitis. Ganciclovir was administered at a mean dose of 10.3 +/- 0.6 mg/kg/day. The mean trough plasma concentration was 0.6 +/- 0.3 mg/L (n = 24), and the mean peak concentration was 7.2 +/- 2.4 mg/L (n = 6). In 12 patients, trough concentrations were below the range that has been associated with effective treatment. Low trough concentrations were associated with treatment failure in 6 patients. Following an increase in the daily dose, improvement was observed in 4 of the 6 patients. These results suggest that low plasma ganciclovir levels are associated with the failure of therapy. Monitoring the plasma concentration of ganciclovir may thus be useful before considering the virus to be resistant to the drug or before switching from ganciclovir to foscarnet.

  3. Spectroscopy of {sup 40}Ca and negative-parity bands

    Energy Technology Data Exchange (ETDEWEB)

    Torilov, S.; Oertzen, W. von; Kokalova, Tz [Fachbereich Physik, Freie Universitaet Berlin, Arnimallee 14, D-14195, Berlin (Germany); Hahn-Meitner-Institut Berlin, Glienicker Strasse 100, D-14109, Berlin (Germany); Thummerer, S.; Bohlen, H.G. [Hahn-Meitner-Institut Berlin, Glienicker Strasse 100, D-14109, Berlin (Germany); Angelis, G.de [Hahn-Meitner-Institut Berlin, Glienicker Strasse 100, D-14109, Berlin (Germany); INFN-Laboratori Nazionali di Legnaro, Legnaro (Italy); Tumino, A. [Hahn-Meitner-Institut Berlin, Glienicker Strasse 100, D-14109, Berlin (Germany); INFN-Laboratori Nazionali del Sud and Universita di Catania, Via S. Sofia 44, I-95123, Catania (Italy); Axiotis, M.; Marginean, N.; Martinez, T.; Napoli, D.R.; Poli, M.De [INFN-Laboratori Nazionali di Legnaro, Legnaro (Italy); Farnea, E.; Lenzi, S.M.; Ur, C. [Dipartimento di Fisica and INFN, Padova (Italy); Rousseau, M.; Papka, P. [Institut de Recherches Subatomiques, IReS, Strasbourg (France)

    2004-03-01

    We have studied the reactions {sup 28}Si+{sup 24}Mg{yields}{sup 52}Fe{yields}{sup 4}0Ca{sup *}+3{alpha} as well as the binary channel {sup 52}Fe{yields}{sup 4}0Ca{sup *}+{sup 12}C{sup *}, in order to search for deformed states, which form rotational bands in {sup 40}Ca. We observe positive- and negative-parity bands. The negative-parity band is proposed to be a partner of an inversion doublet with the positive-parity states being based on 4p-4h configurations. The properties of the positive-parity states are discussed on the basis of the shell model and the parity doublet on the basis of a cluster model with intrinsic reflection asymmetric shapes. (orig.)

  4. Investigation of high-spin states in 53Fe

    Energy Technology Data Exchange (ETDEWEB)

    du Rietz, R.; Williams, S.J.; Rudolph, D.; Ekman, J.; Fahlander,C.; Andreoiu, C.; Axiotis, M.; Bentley, M.A.; Carpenter, M.P.; Chandler,C.; Charity, R.J.; Clark, R.M.; Cromaz, M.; Dewald, A.; de Angelis, G.; Della Vedova, F.; Fallon, P.; Gadea, A.; Hammond, G.; Ideguchi, E.; Lenzi, S.M.; Macchiavelli, A.O.; Marginean, N.; Mineva, M.N.; Moller, O.; DNapoli, .R.; Nespolo, M.; Reviol, W.; Rusu, C.; Saha, B.; Sarantites,D.G.; Seweryniak, D.; Tonev, D.; Ur, C.A.

    2006-04-15

    The fusion-evaporation reactions 28Si(32S,1{alpha}2p1n)53Fe at 125 MeV and 24Mg(32S,2p1n)53Fe at a 95-MeV beam energy were used to investigate excited states in 53Fe. The combination of the Gammasphere Ge detector array and ancillary devices led to the construction of an extensive level scheme comprising some 90 transitions connecting 40 states. The lifetime of the yrast 25/2- state and upper limits for the lifetimes of a number of additional states were determined using the Cologne plunger device coupled to the GASP {gamma}-ray spectrometer. The experimental results are compared to large-scale shell-model calculations using different sets of two-body matrix elements. In particular, predictions on electromagnetic decay properties such as lifetimes, branching ratios, and mixing ratios are studied in detail.

  5. Production of butyl-biodiesel using lipase physically-adsorbed onto electrospun polyacrylonitrile fibers.

    Science.gov (United States)

    Sakai, Shinji; Liu, Yuping; Yamaguchi, Tetsu; Watanabe, Rie; Kawabe, Masaaki; Kawakami, Koei

    2010-10-01

    Butyl-biodiesel production using electrospun polyacrylonitrile fibers with Pseudomonas cepacia lipase immobilized through physical adsorption was studied. About 80% conversion to butyl-biodiesel was achieved after 24h by suspending the catalyst at 2.4 mg/mL in a mixture of rapeseed oil and n-butanol at a molar ratio of 1:3, containing water at 8000 ppm at 40 degrees C. A further 24h of operation resulted in 94% conversion. The initial reaction rate detected for this process was 65-fold faster than those detected for Novozym 435 on a total catalyst mass basis. The immobilized lipase continued to work as a catalyst for 27 d, within a 15% reduction in conversion yield at the outlet of the reactor compared with the average value detected during the first 3d of operation in a continuous butyl-biodiesel production system.

  6. Deformed $sd$-shell nuclei from first principles

    CERN Document Server

    Jansen, G R; Hagen, G; Navrátil, P

    2015-01-01

    We extend the ab initio coupled-cluster effective interaction (CCEI) method to deformed open-shell nuclei with protons and neutrons in the valence space, and compute binding energies and excited states of isotopes of neon and magnesium. We employ a nucleon-nucleon and three-nucleon interaction from chiral effective field theory evolved to a lower cutoff via a similarity renormalization group transformation. We find good agreement with experiment for binding energies and spectra, while charge radii of neon isotopes are underestimated. For the deformed nuclei $^{20}$Ne and $^{24}$Mg we reproduce rotational bands and electric quadrupole transitions within uncertainties estimated from an effective field theory for deformed nuclei, thereby demonstrating that collective phenomena in $sd$-shell nuclei emerge from complex ab initio calculations.

  7. Core correlation effects in multiconfiguration calculations of isotope shifts in Mg I

    CERN Document Server

    Filippin, Livio; Ekman, Jörgen; Jönsson, Per

    2016-01-01

    The present work reports results from systematic multiconfiguration Dirac-Hartree-Fock calculations of isotope shifts for several well-known transitions in neutral magnesium. Relativistic normal and specific mass shift factors as well as the electronic probability density at the origin are calculated. Combining these electronic quantities with available nuclear data, energy and transition level shifts are determined for the $^{26}$Mg$-^{24}$Mg pair of isotopes. Different models for electron correlation are adopted. It is shown that although valence and core-valence models provide accurate values for the isotope shifts, the inclusion of core-core excitations in the computational strategy significantly improves the accuracy of the transition energies and normal mass shift factors.

  8. Free phenolic acids in Ruta graveolens L. in vitro culture.

    Science.gov (United States)

    Ekiert, H; Szewczyk, A; Kuś, A

    2009-10-01

    Eight phenolic acids were determined using HPLC method in methanolic extracts of Ruta graveolens L. (Rutaceae) shoots cultured in vitro on four variants of Linsmaier and Skoog (LS) medium differing in contents of growth regulators, NAA and BAP (ranging between 0.1-3.0 mg/l). Four compounds: protocatechuic, vanillic, syringic and p-coumaric acid were detected and quantified. The total content of metabolites was dependent on LS medium variants. The contents of protocatechuic acid, quantitatively dominating on all tested LS medium variants, were considerable (from 67.15 to 93.24 mg/100 g d.w.) in comparison with its contents in the plant material under analysis (46.36 to 218.27 mg/ 100 g d.w.). This is the first report of the isolation of protocatechuic acid from an in vitro plant culture.

  9. Dissipation kinetics of metalaxyl in cucumber.

    Science.gov (United States)

    Rattan, G S; Sharma, Neeraj

    2012-05-01

    Residues of metalaxyl were estimated in cucumber fruits using Gas Liquid Chromatography (GLC) with Nitrogen phosphorus detector (NPD). Following three applications of Ridomil-MZ @ 0.3% and 0.6%, the average initial deposits of metalaxyl were observed to be 0.19 and 0.24 mg kg(-1), respectively. The residues dissipated below the limit of quantification (LOQ) of 0.02 mg kg(-1) after 10 days at both the dosages. The half-life values (T(1/2)) of metalaxyl was worked out to be 3.5 and 3.0 days, respectively at 0.3% and 0.6% concentration. Thus, a waiting period of 1 day was suggested for the safe consumption of metalaxyl treated cucumber.

  10. Differential effect of ketamine and lidocaine on spontaneous and mechanical evoked pain in patients with nerve injury pain

    DEFF Research Database (Denmark)

    Gottrup, Hanne; Bach, Flemming Winther; Juhl, Gitte Irene

    2006-01-01

    ketamine, an N-methyl-D-aspartate receptor antagonist and lidocaine, a sodium channel blocker, on spontaneous pain, brush-evoked pain, and pinprick-evoked pain in patients with nerve injury pain. METHODS: Twenty patients participated in two randomized, double-blinded, placebo-controlled, crossover...... experiments in which they, on four different days, received a 30-minute intravenous infusion of ketamine (0.24 mg/kg), lidocaine (5 mg/kg), or saline. Ongoing pain, pain evoked by brush and repetitive pinprick stimuli, and acetone was measured before, during, and after infusion. RESULTS: Ketamine...... significantly reduced ongoing pain and evoked pain to brush and pinprick, whereas lidocaine only reduced evoked pain to repetitive pinprick stimuli. In individual patients, there was no correlation between the pain-relieving effect of lidocaine and ketamine on ongoing or mechanically evoked pains. CONCLUSIONS...

  11. High spin spectroscopy near the N=Z line: Channel selection and excitation energy systematics

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, C.E.; Cameron, J.A.; Flibotte, S. [McMaster Univ., Ontario (Canada)] [and others

    1996-12-31

    The total {gamma}-ray and charged-particle energies emitted in fusion-evaporation reactions leading to N=Z compound systems in the A = 50-70 mass region have been measured with the 8{pi} {gamma}-ray spectrometer and the miniball charged-particle detector array. A new method of channel selection has been developed which combines particle identification with these total energy measurements and greatly improves upon the selectivity possible with particle detection alone. In addition, the event by event measurement of total {gamma}-ray energies using the BGO ball of the 8{pi} spectrometer has allowed a determination of excitation energies following particle evaporation for a large number of channels in several different reactions. The new channel selection procedure and excitation energy systematics are illustrated with data from the reaction of {sup 24}Mg on {sup 40}Ca at E{sub lab} = 80MeV.

  12. O conceito de incerteza aplicado aos processos de medição associados à preparação de uma solução de referência para calibração

    Directory of Open Access Journals (Sweden)

    Buchmann José Henrique

    2002-01-01

    Full Text Available The implementation of a quality assurance program in chemical analytical laboratories, that can aid in demonstrate the quality of their results, is an issue of great concern. As a consequence, it is mandatory to give an estimate of the confidence that can be placed on the obtained results. An useful measure of this confidence is the measurement uncertainty and, nowadays, a result without the corresponding uncertainty statement cannot be considered reliable. This paper presents a summary of the most important mechanisms for the evaluation and reporting of the measurement uncertainty. In implementing these principles, it is described the measurement uncertainty estimation associated with the preparation of a uranium elemental reference solution at 2.4 mg.kg-1 from the corresponding certified reference material (in this example at 1003 mg.kg-1.

  13. Non-statistical decay and α-correlations in the 12C+12C fusion-evaporation reaction at 95 MeV

    Science.gov (United States)

    Morelli, L.; Baiocco, G.; D'Agostino, M.; Gulminelli, F.; Bruno, M.; Abbondanno, U.; Appannababu, S.; Barlini, S.; Bini, M.; Casini, G.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gelli, N.; Gramegna, F.; Kravchuk, V. L.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Valdré, S.; Raduta, Ad R.

    2014-07-01

    Multiple alpha coincidences and correlations are studied in the reaction 12C+12C at 95 MeV for fusion-evaporation events completely detected in charge. Two specific channels with carbon and oxygen residues in coincidence with α -particles are addressed, which are associated with anomalously high branching ratios with respect to the predictions of Hauser-Feshbach calculations. Triple alpha emission appears kinematically compatible with a sequential emission from a highly excited Mg. The phase space distribution of α - α coincidences suggests a correlated emission from a Mg compound, leaving an oxygen residue excited above the threshold for neutron decay. These observations indicate a preferential α emission of 24Mg at excitation energies well above the threshold for 6 - α decay.

  14. Sensory quality of drinking water produced by reverse osmosis membrane filtration followed by remineralisation

    DEFF Research Database (Denmark)

    Vingerhoeds, Monique H.; Nijenhuis-de Vries, Mariska A.; Ruepert, Nienke

    2016-01-01

    , permeate, and permeate with added minerals (40 or 120 mg Ca/L, added as CaCO3, and 4 or 24 mg Mg/L added as MgCl2), as well as commercially available bottled drinking waters, to span a relevant product space in which the remineralised samples could be compared. All samples were analysed with respect......Membrane filtration of ground, surface, or sea water by reverse osmosis results in permeate, which is almost free from minerals. Minerals may be added afterwards, not only to comply with (legal) standards and to enhance chemical stability, but also to improve the taste of drinking water made from...... permeate. Both the nature and the concentrations of added minerals affect the taste of the water and in turn its acceptance by consumers. The aim of this study was to examine differences in taste between various remineralised drinking waters.Samples selected varied in mineral composition, i.e. tap water...

  15. Disappearance of collective motion in hot nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Santonocito, D.; Piattelli, P.; Agodi, C.; Alba, R.; Bellia, G.; Coniglione, R.; Del Zoppo, A.; Finocchiaro, P.; Hongmei, F.; Maiolino, C.; Migneco, E.; Sapienza, P. [INFN-LNS, Laboratori Nazionali del Sud, Catania (Italy); Blumenfeld, Y.; Delaunay, F.; Frascaria, N.; Lima, V.; Scarpaci, J. [Institut de Physique Nucleaire, IN2P3-CNRS, 91 - Orsay (France); Migneco, E. [Catania Univ., Dipartimento di Fisica (Italy)

    2003-07-01

    The evolution of the GDR {gamma} yield for excitation energies between 160 and 300 MeV has been investigated in nuclei of mass A {approx} 126 through the reactions {sup 116}Sn + {sup 12}C and {sup 24}Mg at 17 and 23 A*MeV. Gamma-rays were detected with MEDEA array in coincidence with residues detected in MACISTE. The evolution of the GDR parameters has been investigated as a function of the linear momentum transferred to the fused system. This procedure allowed us to select hot nuclei produced in incomplete fusion reactions with different excitation energies. The analysis of the {gamma} spectra and their comparison with CASCADE calculations is presented. Results suggest a saturation of the GDR yield between 200 and 300 MeV excitation energy. (authors)

  16. [The Effect of Cadmium on the Efficiency of Development of Legume-Rhizobium Symbiosis].

    Science.gov (United States)

    Chuhukova, O V; Postrigan, B N; Baimiev, A Kh; Chemeris, A V

    2015-01-01

    Screening of nodule bacteria (rhizobia) forming symbiotic relationships with legumes has been performed in order to isolate strains resistant to cadmium ions in a wide range of concentrations (6-132 mg/kg). The effect ofcadmium salts (6, 12, 24 mg/kg) on the legume-rhizobium symbiosis ofthe pea Pisum sativum L. with Rhizobium leguminosarum and of the fodder galega Galega orientalis Lam. with Rhizobium galegae has been studied under experimental laboratory conditions. No statistically significant differences have been revealed in the growth and biomass of plants with regard to the control in the range of concentrations given above. However, it was found that cadmium inhibited nodulation in P. sativum and stimulated it in G. orientalis.

  17. Extraction and isolation of dictamnine, obacunone and fraxinellone from Dictamnus dasycarpus Turcz. by supercritical fluid extraction and high-speed counter-current chromatography

    Directory of Open Access Journals (Sweden)

    Daijie Wang

    2012-01-01

    Full Text Available Supercritical fluid extraction was used to extract active compounds from the Chinese traditional medicinal D. dasycarpus under the pressure of 30 MPa and temperature of 45 ºC. Further separation and purification was established by high-speed counter-current chromatography (HSCCC with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:0.8:1.3:0.9, volume ratio. The separation yielded a total of 47 mg of dictamnine, 24 mg of obacunone and 83 mg of fraxinellone from 1.0 g of the crude extract in one step separation with the purity of 99.2, 98.4 and 99.0%, respectively, as determined by HPLC. The chemical structures of these compounds were identified by ESI-MS, IR, ¹H-NMR and 13C-NMR.

  18. Studies of Pb2+ adsorption by Moringa oleifera Lam. seeds from an aqueous medium in a batch system.

    Science.gov (United States)

    Meneghel, Ana Paula; Gonçalves, Affonso Celso; Tarley, César Ricardo Teixeira; Stangarlin, José Renato; Rubio, Fernanda; Nacke, Herbert

    2014-01-01

    The efficiency of Moringa (Moringa oleifera Lam.) seeds for removing lead ions (Pb(2+)) from water was evaluated. Parameters such as solution pH, adsorbent mass, contact time between solution and adsorbent, isotherms, thermodynamic, kinetics, and desorption were evaluated. The maximum adsorption capacity of the biosorbent was found to be 12.24 mg g(-1). In order to verify the effectiveness of this material, comparative studies were performed with activated carbon under the same optimal conditions for the construction of isotherms and the desorption process. Average desorption rate values led to the assumption that a strong interaction took place between the adsorbents and the metal ions. Thus, it has been concluded that the biosorbent studied herein can be considered very effective and feasible for remediating Pb(2+)-contaminated solutions, since this material is itself an untreated and low-cost byproduct.

  19. Bioaccumulation and physiological effects of excess lead in a roadside pioneer species Sonchus oleraceus L.

    Science.gov (United States)

    Xiong, Z T

    1997-01-01

    Seedlings of Sonchus oleraceus L. were transplanted to soil supplied with lead acetate at dosages of 0, 800, 1600 and 3200 mg kg(-1) DW. Measures of chlorophyll content, peroxidase (POD) activity, shoot length, biomass and Pb content in the plant tissues were obtained from the experimental plants. With increasing amounts of Pb in the soil, the chlorophyll content, shoot length and biomass decreased, while POD activity and Pb content in the plant tissues increased. At 3200 mg kg(-1) Pb treatment, Pb content in the plant leaf, stem and root were 65.67, 149.82 and 1113.24 mg kg(-1), respectively. Only at 3200 mg kg(-1) Pb treatment did chlorophyll content, shoot length and biomass significantly increase by 18, 15 and 44%, respectively, while POD decreased by 39% over the control. The potential of applying this species in phytoremediation of Pb contaminated roadside soils and thus restoration of the roadside vegetation are discussed.

  20. Study of {sup nat}Mg(d,d{sub 0}) reaction at detector angles between 90° and 170°, for the energy range E{sub d,lab}=1660–1990 keV

    Energy Technology Data Exchange (ETDEWEB)

    Patronis, N., E-mail: npatronis@uoi.gr [Department of Physics, University of Ioannina, 45110 Ioannina (Greece); Aslanoglou, X. [Department of Physics, University of Ioannina, 45110 Ioannina (Greece); Axiotis, M. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, N.C.S.R. Demokritos, Aghia Paraskevi, 15310 Athens (Greece); Georgiadou, A. [Department of Physics, University of Ioannina, 45110 Ioannina (Greece); Kokkoris, M. [Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens (Greece); Lagoyannis, A. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, N.C.S.R. Demokritos, Aghia Paraskevi, 15310 Athens (Greece); Misaelides, P. [Department of Chemistry, Aristotle University, GR-54124 Thessaloniki (Greece); Paneta, V. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, N.C.S.R. Demokritos, Aghia Paraskevi, 15310 Athens (Greece); Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens (Greece)

    2014-10-15

    In the present work, the study of the {sup nat}Mg(d,d{sub 0}) is presented for the energy range E{sub d,lab} = 1660–1990 keV (in steps of 5 keV), for detector angles between 90° and 170°. Elastic scattering data for two forward angles (55° and 70°) were also obtained. In order to validate the obtained experimental results a thick Mg sample with Au evaporated on top was fabricated and benchmarking measurements were performed at various deuteron beam energies. The results of the present work are complementary to the recently published {sup 24}Mg(d,p{sub 0,1,2}) reaction cross section data, thus facilitating the simultaneous depth profiling study of magnesium by both the d-NRA and EBS techniques.

  1. Avaliação do potencial anti-hiperplásico prostático de extrato e frações de Calendula officinalis e alguns fitosteróis em ratos

    OpenAIRE

    Schoenfelder,Tatiana

    2003-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Farmácia. O objetivo deste trabalho foi avaliar o efeito anti-hiperplásico prostático do extrato bruto hidroalcoólico, fração supercrítica e diclorometânica de Calendula officinalis e alguns fitosteróis. Foram utilizados: ratos machos de 40 dias (peso: 140 g, n= 6) foram castrados e submetidos a tratamento com testosterona (T 2,4 mg/kg rato) durante 7 dias para indução...

  2. Serum cholesterol in healthy postmenopausal women.

    Science.gov (United States)

    Samanta, B B

    1998-05-01

    Hypercholes erolaemia is a modifiable risk factor in atherosclerosis. Women lose their relative protection against coronory heart disease at menopause because of changed lipid profile due to oestrogen deficiency. Total serum cholesterol was estimated in 82 healthy postmenopausal women in the age group of 46-72 years (51.5 +/- 7.39). Thirty five healthy pre-menopausal women in the age group of 18-38 years (29.5 +/- 6.4) served as controls. The mean serum cholesterol concentration was significantly higher in the postmenopausal group compared to control group (178.5 +/- 39.8 Vs 155.4 +/- 24 mg/dl; P < 0.01). Serum cholesterol concentration in the study group was not related to social class, dietary habit and obesity.

  3. Novel Erythrocyte-like Graphene Microspheres with High Quality and Mass Production Capability via Electrospray Assisted Self-Assembly

    Science.gov (United States)

    Tian, Yayang; Wu, Guan; Tian, Xike; Tao, Xiaoming; Chen, Wei

    2013-11-01

    We report for the first time a novel erythrocyte-like graphene microsphere (ELGMs) which can be produced with high quality and mass production capability via electrospray assisted self-assembly. Through simple electrospray treatment of GO suspension into coagulation bath followed by chemical reduction, large quantity of ELGMs with uniform morphology and size can be obtained with production rate of around 2.4 mg/h. Compared with other 3D structures, the ELGMs have a very interesting structural characteristic of perfect exterior doughnut shape and interior porous network. Accordingly, the as-prepared porous ELGMs exhibit excellent capability for fast and recyclable removal of oil and toxic organic solvents from water, reaching up to 216 times of its weight in absorption efficiency, which is tens of times higher than that of conventional sorbent materials. It is strongly believed that the novel hierarchical graphene structures and synergy among different techniques will lead to more future advances in graphene applications.

  4. The side effect profile of buspirone in comparison to active controls and placebo.

    Science.gov (United States)

    Newton, R E; Casten, G P; Alms, D R; Benes, C O; Marunycz, J D

    1982-12-01

    Animal studies and the original study comparing buspirone with diazepam and placebo indicated that sedative-hypnotic side effects and impairment in psychomotor function would be less with buspirone than with diazepam. This was borne out by the present double-blind study in which almost 700 patients received buspirone. Mean daily doses were buspirone, 20 mg; diazepam, 20 mg; and clorazepate, 24 mg. Sedation, lethargy, and depression were significantly less with buspirone than with diazepam or clorazepate and were comparable to placebo. There was no indication that other types of side effects would differ significantly from those seen with the benzodiazepines. Nervousness, headache, and dizziness were experienced more frequently with buspirone than with placebo.

  5. [Cadmium distribution in tissues and Na,K-ATPase activity of the skin of the frog Rana temporaria in different routes of cadmium uptake by the body].

    Science.gov (United States)

    Vasil'eva, V F; Gusev, G P; Krestinskaia, T V; Burovina, I V; Ukhanov, K Iu

    1987-01-01

    Accumulation, distribution of Cd in tissues and its toxic effect depend of the mode of uptake of Cd by the organism. Subcutaneous injections of Cd (0.12-0.24 mg/100 g per day) for 10 days resulted in a significant accumulation of Cd in the liver and kidney. No death cases were observed. Addition of CdCl2 to the aquatic environment (more than 0.002%) caused acute toxic effect on frogs. Within 10 days, significant amounts of Cd were found in the skin, especially in its outside layers, small amounts were found in the kidney and liver. High external concentrations of CdCl2 (0.005%) inhibited the activity of Na,K-ATPase in the skin epithelium. It is suggested that adaptive detoxication of cadmium in the liver and kidney operating in mammals, is ineffective in amphibians provided cadmium uptake occurs via the skin.

  6. Effect of roasting conditions on several chemical constituents of Vietnam Robusta coffee

    Directory of Open Access Journals (Sweden)

    Tran VAN CUONG

    2014-12-01

    Full Text Available This study was conducted to determine the effect of roasting conditions on chemical constituents of Vietnam robusta coffee. The contents of acrylamide, chlorogenic acid and tannins were higher in green coffee than in roasted coffee and decreased as roasting condition increased, which ranged from 6.53 to 91.36 μg/100g, 1.54 to 55.51 mg/g and 3.14 to 651.59 mg/10g, respectively. In addition, the content of trigonelline ranged from 1.43 to 64.24 mg/10g, which gave the highest value in green coffee, then decreased rapidly, while in the Italian roast it was not present at all. Caffeine content ranged from 15.30 to 35.91 mg/g and presented the lowest value in the case of green coffee, then increased reaching the highest value at 240 oC, after that decreasing gradually and slowly.

  7. A new system for the simultaneous measurement of δ{sup 13}C and δ{sup 15}N by IRMS and radiocarbon by AMS on gaseous samples: Design features and performances of the gas handling interface

    Energy Technology Data Exchange (ETDEWEB)

    Braione, Eugenia; Maruccio, Lucio; Quarta, Gianluca; D’Elia, Marisa; Calcagnile, Lucio, E-mail: lucio.calcagnile@unisalento.it

    2015-10-15

    We present the general design features and preliminary performances of a new system for the simultaneous AMS-{sup 14}C and IRMS δ{sup 13}C and δ{sup 15}N measurements on samples with masses in the μg range. The system consists of an elemental analyzer (EA), a gas splitting unit (GSU), a IRMS system, a gas handling interface (GHI) and a sputtering ion source capable of accepting gaseous samples. A detailed description of the system and of the control software supporting unattended operation are presented together with the first performance tests carried out by analyzing samples with masses ranging from 8 μgC to 2.4 mgC. The performances of the system were tested in term of stability of the ion beam extracted from the ion source, precision and accuracy of the results by comparing the measured isotopic ratios with those expected for reference materials.

  8. Interlaboratory comparison of magnesium isotopic compositions of 12 felsic to ultramafic igneous rock standards analyzed by MC-ICPMS

    Science.gov (United States)

    Teng, Fang-Zhen; Yin, Qing-Zhu; Ullmann, Clemens V.; Chakrabarti, Ramananda; Pogge von Strandmann, Philip A. E.; Yang, Wei; Li, Wang-Ye; Ke, Shan; Sedaghatpour, Fatemeh; Wimpenny, Joshua; Meixner, Anette; Romer, Rolf L.; Wiechert, Uwe; Jacobsen, Stein B.

    2015-09-01

    To evaluate the interlaboratory mass bias for high-precision stable Mg isotopic analysis of natural materials, a suite of silicate standards ranging in composition from felsic to ultramafic were analyzed in five laboratories by using three types of multicollector inductively coupled plasma mass spectrometer (MC-ICPMS). Magnesium isotopic compositions from all labs are in agreement for most rocks within quoted uncertainties but are significantly (up to 0.3‰ in 26Mg/24Mg, >4 times of uncertainties) different for some mafic samples. The interlaboratory mass bias does not correlate with matrix element/Mg ratios, and the mechanism for producing it is uncertain but very likely arises from column chemistry. Our results suggest that standards with different matrices are needed to calibrate the efficiency of column chemistry and caution should be taken when dealing with samples with complicated matrices. Well-calibrated standards with matrix elements matching samples should be used to reduce the interlaboratory mass bias.

  9. Treatment of intermittent claudication with defibrotide or mesoglycan. A double blind study.

    Science.gov (United States)

    Laurora, G; Ambrosoli, L; Cesarone, M R; De Sanctis, M T; Incandela, L; Marelli, C; Belcaro, G

    1994-06-01

    Forty-four patients with intermittent claudication were included and randomised in two groups respectively treated with oral defibrotide (one 400 mg tablet bid) or oral mesoglycan (one 24 mg tablet bid) for 6 months. Twenty-two subjects completed the study in the defibrotide group and 20 in the mesoglycan group. The two treatments were well tolerated and the two drop outs in the mesoglycan group were not due to medical causes. In the defibrotide group, after 1 month the pain-free walking distance (PFWD) increased from 473 +/- 96 m to 586 +/- 84 (p mesoglycan group. The improvement in walking was possibly due to the action of defibrotide increasing local fibrinolysis and decreasing the distal vasospasm present in subjects with peripheral vascular disease and intermittent claudication.

  10. [Mesoglycan in acute focal cerebral ischemia].

    Science.gov (United States)

    Cazzato, G; Zorzon, M; Masé, G; Antonutti, L; Iona, L G

    1989-01-01

    An open, randomized, controlled study including 57 patients with acute cerebral infarct was performed. All the patients, followed and controlled by the same examiner, received, in the first ten days, 24 mg/die i.v. of dexamethasone. 28 patients were also treated with mesoglycan (150 mg/die i.m. for five days and 144 mg/die per os for a further twenty-five days). The differences between the basal and final scores in the mesoglycan group and in the controls were not statistically significant as analysed by the Mann-Whitney U test. The mesoglycan influenced only slightly the laboratory values (PT, PTT, alkaline phosphatase, GOT, GPT, cholesterol and triglycerides, fibrinogen, blood glucose, azotemia and creatinine) performed before the beginning of the treatment, as their changes after thirty days of therapy were in the normal range. The mesoglycan was very well tolerated and no side-effects were observed during the treatment.

  11. Municipal Wastewater Treatment by A Two-Stage, Submerged Membrane Bioreactor%二段淹没式膜生物反应器处理城市污水的研究

    Institute of Scientific and Technical Information of China (English)

    张绍园; 闫百瑞

    2003-01-01

    采用九保田板式膜,设计了二段淹没式膜生物反应器处理城市生活污水.运行结果显示,二段淹没式膜生物反应器能够增强高能级生物体蠕虫生长与少产污泥的目的.在污泥负荷为0.35~0.65 g[COD]/(g[SS]·d)和容积负荷为2~5 g[COD]/(L·d)的条件下,反应器出水COD和NH3-N的质量浓度分别为18.67 mg/L和0.24mg/L,污泥产率为0.1 kg[SS]/kg[COD].

  12. Relationship between cisplatin or nedaplatin-induced nephrotoxicity and renal accumulation.

    Science.gov (United States)

    Kawai, Yoshiko; Taniuchi, Saburo; Okahara, Shigeki; Nakamura, Masuhisa; Gemba, Munekazu

    2005-08-01

    Nedaplatin is known to exhibit antitumor activity similar to that of cisplatin. However, concerning side effects, nedaplatin causes renal toxicity less frequently than cisplatin. In this study, we compared the incidence of renal toxicity between cisplatin and nedaplatin by investigating the difference in kidney tissue accumulation. Kidney tissue accumulation of cisplatin administered at 3.75 mg/kg was similar to that of nedaplatin administered at 24 mg/kg. At these doses, the plasma creatinine level and urinary excretion of glucose and N-acetyl-beta-D-glucosaminidase (NAG) similarly increased. There was a correlation between kidney accumulation of cisplatin and nedaplatin and the increases in plasma creatinine level and urinary excretion of NAG. Therefore, our results suggest that nedaplatin less frequently causes renal toxicity in comparison to cisplatin due to lower kidney accumulation.

  13. Origin of fine structure of the giant dipole resonance in sd-shell nuclei

    CERN Document Server

    Fearick, R W; Matsubara, H; von Neumann-Cosel, P; Richter, A; Roth, R; Tamii, A

    2014-01-01

    A set of high resolution zero-degree inelastic proton scattering data on 24Mg, 28Si, 32S, and 40Ca provides new insight into the long-standing puzzle of the origin of fragmentation of the Giant Dipole Resonance (GDR) in sd-shell nuclei. Understanding is provided by state-of-the-art theoretical Random Phase Approximation (RPA) calculatios for deformed nuclei using for the first time a realistic nucleon-nucleon interaction derived from the Argonne V18 potential with the unitary correlation operator method and supplemented by a phenomenological three-nucleon contact interaction. A wavelet analysis allows to extract significant scales both in the data and calculations characterizing the fine structure of the GDR. The fair agreement supports that the fine structure arises from ground-state deformation driven by alpha clustering.

  14. Momentum distribution of N$^*$ in nuclei

    CERN Document Server

    Kelkar, N G

    2016-01-01

    Due to its dominance in the low energy eta-nucleon interaction, the S11 N$^*$(1535) resonance enters as an important ingredient in the analyses of experiments aimed at finding evidence for the existence of eta-mesic nuclei. The static properties of the resonance get modified inside the nucleus and its momentum distribution is used in deciding these properties as well as the kinematics in the analyses. Here we show that given the possibility for the existence of an N$^*$-$^3$He quasibound state, the relative momentum distribution of an N$^*$ and $^3$He inside such a $^4$He is narrower than that of neutron-$^3$He in $^4$He. Results for the N$^*$-$^{24}$Mg system are also presented. The present exploratory work could be useful in motivating searches of exotic N$^*$-nucleus quasibound states as well as in performing analyses of eta meson production data.

  15. Concurrent chemoradiotherapy for advanced cervical cancer. A pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Kodama, Junichi; Hashimoto, Ichiro; Seki, Noriko; Hongo, Atsushi; Mizutani, Yasushi; Miyagi, Yasunari; Yoshinouchi, Mitsuo; Kudo, Takafumi [Okayama Univ. (Japan). School of Medicine

    2001-03-01

    Recently, attempts have made to use radiotherapy in combination with chemotherapy in various solid tumors including cervical cancer. Twenty-four patients with locally advanced cervical cancer were treated with concurrent Carboplatin (16-24 mg/m{sup 2}/day) or Nedaplatin (20 mg/m{sup 2}/week) and conventional radiotherapy. Of 13 evaluable patients, there were nine complete responders and four partial responders. There was no renal damage or grade 4 hematological toxicity. Gastrointestinal adverse reactions were mild. One patient had grade 3 dermatologic toxicity after delayed radiation therapy. This pilot study suggests that daily Carboplatin or weekly Nedaplatin administered with standard radiation therapy is safe, well-tolerated, and thus may be useful as a radiation sensitizer in the treatment of locally advanced cervical cancer. (author)

  16. Simultaneous derivative spectrophotometric estimation of aceclofenac and tramadol with paracetamol in combination solid dosage forms

    Directory of Open Access Journals (Sweden)

    Srinivasan K

    2007-01-01

    Full Text Available A derivative spectrophotometric procedure has been developed for the simultaneous determination of individual combination of aceclofenac and tramadol with paracetamol in combined tablet preparation. Tablet extracts of the drugs were prepared in distilled water. The zero crossing point technique and the compensation technique were used to estimate the amount of each drug in the combined formulations, and were compared. The results were found to be accurate and free from interferences. The procedure is rapid, simple, nondestructive, and does not require solutions of equations. Calibration graphs are linear (r=0.9999, with a zero intercept up to 24 mg/ml of each drug in combination with paracetamol. Detection limits at the p = 0.05 level of significance were calculated to be 0.5 mg/ml of aceclofenac, tramadol and paracetamol respectively.

  17. Clonazepam improves dopamine supersensitivity in a schizophrenia patient: a case report

    Science.gov (United States)

    Fukai, Mina; Hirosawa, Tetsu; Takahashi, Tetsuya; Kaneda, Reizo; Kikuchi, Mitsuru; Minabe, Yoshio

    2016-01-01

    Dopamine supersensitivity is an important consideration for assessing treatment-resistant schizophrenia. The emergence of dopamine supersensitivity might be related to upregulation of dopamine D2 receptor, which engenders tolerance to antipsychotics, rebound psychosis, and tardive dyskinesia (TD). A 24-year-old man with a history of treatment-resistant schizophrenia was hospitalized for treatment of bone fracture sustained during a suicide attempt. After the operation, his clinical symptoms implied malignant catatonia. The patient discontinued antipsychotics without rebound psychosis under clonazepam treatment. His psychotic symptoms were controlled further with 24 mg/day aripiprazole without relapse or worsening. Clonazepam might be an effective option for the management of dopamine supersensitivity psychosis (DSP). PMID:28348731

  18. Effect of precipitation on elastic modulus of Al-Zn-Mg-Cu-Li alloys

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhong-kui; ZHOU Tie-tao; LIU Pei-ying; LI Huan-xi; CHEN Chang-qi

    2006-01-01

    Al-5.6Zn-3.0Mg-1.6Cu-1.1Li-0.24Cr alloys and Al-8.0Zn-2.4Mg-2.4Cu-1.1Li-0.18Zr alloys (mass fraction, %) were aged by different processes. The microstructure and mechanical properties were determined by transmission electron microscopy(TEM),tensile test and Vicker's hardness test. The experimental results show that the most signified hardening is obtained by double-ageing or multi-ageing for the Al-Zn-Mg-Cu-Li alloys. The yield strength and the elastic modulus of the Li-containing alloys have relationships with ageing processes. The elastic modulus of Li-containing alloys decreases with the increment of precipitates though it is higher than that of Al-Zn-Mg-Cu alloy.

  19. Nuclear Level Density with Non-zero Angular Momentum

    Institute of Scientific and Technical Information of China (English)

    A.N. Behkami; M. Gholami; M. Kildir; M. Soltani

    2006-01-01

    The statistical properties of interacting fermions have been studied for various angular momentum with the inclusion of pairing interaction. The dependence of the critical temperature on angular momentum for several nuclei,have been studied. The yrast energy as a function of angular momentum for 28 Si and 24Mg nuclei have been calculated up to 60.0 MeV of excitation energy. The computed limiting angular momenta are compared with the experimental results for 26Al produced by 12C + 14N reaction. The relevant nuclear level densities for non-zero angular momentum have been computed for 44Ti and l36Ba nuclei. The results are compared with their corresponding values obtained from the approximateformulas.

  20. Experimental Determination of the 24Mg I (3s3p)3P2 Lifetime

    DEFF Research Database (Denmark)

    Jensen, Brian Bak; He, Ming; Westergaard, Philip Grabow;

    2011-01-01

    We present the first experimental determination of the electric-dipole forbidden (3s3p)3P2¿(3s2)1S0 (M2) transition rate in 24Mg and compare to state-of-the-art theoretical predictions. Our measurement exploits a magnetic trap isolating the sample from perturbations and a magneto-optical trap...... as an amplifier converting each 3P2¿1S0 decay event into millions of photons readily detected. The transition rate is determined to be (4.87±0.3)×10-4¿¿s-1 corresponding to a 3P2 lifetime of 2050-110+140 sec. This value is in agreement with recent theoretical predictions, and to our knowledge the longest lifetime...

  1. Towards a Mg lattice clock: Observation of the $^1S_{0}-$$^3P_{0}$ transition and determination of the magic wavelength

    CERN Document Server

    Kulosa, A P; Zipfel, K H; Rühmann, S; Sauer, S; Jha, N; Gibble, K; Ertmer, W; Rasel, E M; Safronova, M S; Safronova, U I; Porsev, S G

    2015-01-01

    We optically excite the electronic state $3s3p~^3P_{0}$ in $^{24}$Mg atoms, laser-cooled and trapped in a magic-wavelength lattice. An applied magnetic field enhances the coupling of the light to the otherwise strictly forbidden transition. We determine the magic wavelength, the quadratic magnetic Zeeman shift and the transition frequency to be 468.463(207)$\\,$nm, -206.6(2.0)$\\,$MHz/T$^2$ and 655 058 646 691(101)$\\,$kHz, respectively. These are compared with theoretical predictions and results from complementary experiments. We also developed a high-precision relativistic structure model for magnesium, give an improved theoretical value for the blackbody radiation shift and discuss a clock based on bosonic magnesium.

  2. Scalable arrays of RF Paul traps in degenerate Si

    CERN Document Server

    Britton, J; Beall, J; Blakestad, R B; Wesenberg, J H; Wineland, D J

    2009-01-01

    We report techniques for the fabrication of multi-zone linear RF Paul traps that exploit the machinability and electrical conductivity of degenerate silicon. The approach was tested by trapping and laser cooling 24Mg+ ions in two trap geometries: a single-zone two-layer trap and a multi-zone surface-electrode trap. From the measured ion motional heating rate we determine an electric field spectral density at the ion's position of approximately 1E-10 (V/m)^2/Hz at a frequency of 1.125 MHz when the ion lies 40 micron above the trap surface. One application of these devices is controlled manipulation of atomic ion qubits, the basis of one form of quantum information processing.

  3. [Visceral leishmaniasis: new drugs].

    Science.gov (United States)

    Minodier, P; Robert, S; Retornaz, K; Garnier, J M

    2003-12-01

    The standard treatment of visceral leishmaniasis is pentavalent antimony (meglumine antimoniate or sodium stibogluconate), but toxicity is frequent with this drug. Moreover, antimony unresponsiveness is increasing, both in immunocompetent and in immunosuppressed patients. Amphotericin B is a polyene macrolide antibiotic that binds to sterols in cell membranes. It is the most active antileishmanial agent in use. Its infusion-related and renal toxicity may be reduced by lipid-based delivery. Liposomal amphotericin B (Ambisome) seems to be less toxic than other amphotericin B lipid formulations (Amphocil, Amphotec). Optimal drug regimens of Ambisome vary from one geographical area to another. In the Mediterranean Basin, a total dose of 18 to 24 mg/kg is safe and effective. Shortening the duration of treatment without decreasing the total dose (i.e., 10 mg/kg/day for 2 days) seems promising to reduce the global cost of the therapy.

  4. A new approach for cluster structures in $^{16}$O and $^{20}Ne$

    Indian Academy of Sciences (India)

    NILOUFAR ZOGHI-FOUMANI; MOHAMMAD REZA SHOJAEI; ALI AKBAR RAJABI

    2017-04-01

    In this article, the cluster–cluster interaction between $\\alpha$-clusters in $^{16}$O and $^{20}$Ne is studied theoretically. Using the generalized Nikiforov–Uvarov (NU) technique, the clusterization energy for these nuclei is calculated. Based on the obtained results, one can find out that the clustering phenomenon does not take place neither at the ground state, nor at the excited states of these nuclei and it is more probable at energies among excited levels. It is shown that the formulation presented for the clustering phenomenon reproduces the results obtained in previous experimental and theoretical attempts. It is worth mentioning that the consistency of the results with the previous experimental and theoretical predictions for clustering phenomenon in $^{16}$O and $^{20}$Ne indicates the reliability of this formulation for various types of light $\\alpha$-conjugate nuclei, such as $^{8}$Be, $^{12}$C, $^{24}$Mg and so on.

  5. Somatic embryo-like structures of strawberry regenerated in vitro on media supplemented with 2,4-D and BAP.

    Science.gov (United States)

    Omar, Genesia F; Mohamed, Fouad H; Haensch, Klaus-Thomas; Sarg, Sawsan H; Morsey, Mohamed M

    2013-09-01

    Somatic embryo-like structures (SELS) were produced in vitro from leaf disk and petiole explants of two cultivars of strawberry (Fragaria x ananassa Duch) on Murashige and Skoog medium with different concentrations and combinations of 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BAP) and sucrose to check the embryonic nature of these structures histologically. A large number of SELS could be regenerated in both cultivars on media with 2-4 mg L(-1) 2,4-D in combination with 0.5 -1 mg L(-1) BAP and 50 g x L(-1) sucrose. Histological examination of SELS revealed the absence of a root pole. Therefore these structures cannot be strictly classified as somatic embryos. The SELS formed under the tested culture conditions represent malformed shoot-like and leaf-like structures. The importance of these results for the propagation of strawberries via somatic embryogenesis is discussed.

  6. Ground and excited states of doubly open-shell nuclei from ab initio valence-space Hamiltonians

    CERN Document Server

    Stroberg, S R; Holt, J D; Bogner, S K; Schwenk, A

    2015-01-01

    We present ab initio predictions for ground and excited states of doubly open-shell fluorine and neon isotopes based on chiral two- and three-nucleon interactions. We use the in-medium similarity renormalization group, in both flow-equation and Magnus formulations, to derive mass-dependent sd valence-space Hamiltonians. The experimental ground-state energies are reproduced through neutron number N=14, beyond which a new targeted normal-ordering procedure improves agreement with data and large-scale multi-reference calculations. For spectroscopy, we focus on neutron-rich 23-26F and 24-26Ne isotopes near N=14,16 magic numbers. In all cases we find an agreement with experiment competitive with established phenomenology. Moreover, yrast states are well described in 20Ne and 24Mg, providing an ab initio description of deformation in the medium-mass region.

  7. Usefulness of Adalimumab in the Treatment of Refractory Uveitis Associated with Juvenile Idiopathic Arthritis

    Science.gov (United States)

    García-De-Vicuña, Carmen; Díaz-Llopis, Manuel; Salom, David; Bou, Rosa; Díaz-Cascajosa, Jesus; Cordero-Coma, Miguel; Ortega, Gabriela; Ortego-Centeno, Norberto; Suarez-De-Figueroa, Marta; Cruz-Martínez, Juan; Fonollosa, Alex; Blanco, Ricardo; García-Aparicio, Ángel María; Benítez-Del-Castillo, Jose M.; Antón, Jordi

    2013-01-01

    Purpose. To assess the efficacy and safety of adalimumab in patients with juvenile idiopathic arthritis (JIA) and associated refractory uveitis. Design. Multicenter, prospective case series. Methods. Thirty-nine patients (mean [SD] age of 11.5 [7.9] years) with JIA-associated uveitis who were either not responsive to standard immunosuppressive therapy or intolerant to it were enrolled. Patients aged 13–17 years were treated with 40 mg of adalimumab every other week for 6 months and those aged 4–12 years received 24 mg/m2 body surface. Results. Inflammation of the anterior chamber (2.02 [1.16] versus 0.42 [0.62]) and of the posterior segment (2.38 [2.97] versus 0.35 [0.71] decreased significantly between baseline and the final visit (P uveitis and may reduce steroid requirement. PMID:24489444

  8. Development of high performance liquid chromatography method for miconazole analysis in powder sample

    Science.gov (United States)

    Hermawan, D.; Suwandri; Sulaeman, U.; Istiqomah, A.; Aboul-Enein, H. Y.

    2017-02-01

    A simple high performance liquid chromatography (HPLC) method has been developed in this study for the analysis of miconazole, an antifungal drug, in powder sample. The optimized HPLC system using C8 column was achieved using mobile phase composition containing methanol:water (85:15, v/v), a flow rate of 0.8 mL/min, and UV detection at 220 nm. The calibration graph was linear in the range from 10 to 50 mg/L with r 2 of 0.9983. The limit of detection (LOD) and limit of quantitation (LOQ) obtained were 2.24 mg/L and 7.47 mg/L, respectively. The present HPLC method is applicable for the determination of miconazole in the powder sample with a recovery of 101.28 % (RSD = 0.96%, n = 3). The developed HPLC method provides short analysis time, high reproducibility and high sensitivity.

  9. Identification and quantification of estrogenic compounds in recycled and virgin paper for household use as determined by an in vitro yeast estrogen screen and chemical analysis

    DEFF Research Database (Denmark)

    Vinggaard, Anne; Körner, Wolfgang; Lund, Kirsten H.

    2000-01-01

    for household use. Twenty different brands of kitchen rolls, nine of which were made from recycled paper and the remainder from virgin paper, were obtained from retail shops. Paper extracts were subjected to (a) determination of the total estrogenic activity by using an in vitro estrogen screen based on yeast......The use of recycled paper for the manufacture of food contact materials is widespread, but very little is known about the presence of potential contaminants in the paper. The purpose of this study was to assess the worst-case migration of estrogenic active compounds using extracts of paper...... paper and two from virgin paper. The chemical analysis revealed that extracts made from recycled paper contained levels of bisphenol A ranging from 0.6 to 24 mg/kg of kitchen roll, whereas extracts from virgin paper contained no bisphenol A or only negligible amounts. In contrast, 4-tert-octylphenol, 4...

  10. Di-lepton yield from the decay of excited [sup 28]Si states

    Energy Technology Data Exchange (ETDEWEB)

    Bacelar, J.C. (Kernfysisch Versneller Inst., Groningen (Netherlands)); Buda, A. (Kernfysisch Versneller Inst., Groningen (Netherlands)); Balanda, A.; Krasznahorkay, A. (Kernfysisch Versneller Inst., Groningen (Netherlands)); Ploeg, H. van der (Kernfysisch Versneller Inst., Groningen (Netherlands)); Sujkowski, Z.; Woude, A. van der (Kernfysisch Versneller Inst., Groningen (Netherlands))

    1994-03-07

    The first dilepton yield measurements from excited nuclear states obtained with a new Positron-Electron Pair Spectroscopic Instrument (PEPSI) are reported. Nuclear states in [sup 28]Si, with an initial excitation energy E[sup *] =50 MeV, were populated via the isospin T=0 reaction [sup 4]He+[sup 24]Mg and the mixed-isospin [sup 3]He+[sup 25]Mg reaction. In both reactions the dilepton (e[sup +]e[sup -]) and photon decay yields were measured concurrently. An excess of counts in the e[sup +]e[sup -] spectrum, over the converted photon yield, is observed in the energy region above 15 MeV. An analyses is discussed whereby the observed excess counts are assumed to represent the isoscalar E0 strength in excited nuclear states. (orig.)

  11. Three-stage classical molecular dynamics model for simulation of heavy-ion fusion

    Directory of Open Access Journals (Sweden)

    Godre Subodh S.

    2015-01-01

    Full Text Available A three-stage Classical Molecular Dynamics (3S-CMD approach for heavy-ion fusion is developed. In this approach the Classical Rigid-Body Dynamics simulation for heavy-ion collision involving light deformed nucleus is initiated on their Rutherford trajectories at very large initial separation. Collision simulation is then followed by relaxation of the rigid-body constrains for one or both the colliding nuclei at distances close to the barrier when the trajectories of all the nucleons are obtained in a Classical Molecular Dynamics approach. This 3S-CMD approach explicitly takes into account not only the long range Coulomb reorientation of the deformed collision partner but also the internal vibrational excitations of one or both the nuclei at distances close to the barrier. The results of the dynamical simulation for 24Mg+208Pb collision show significant modification of the fusion barrier and calculated fusion cross sections due to internal excitations.

  12. Towards tooth friendly soft drinks.

    Science.gov (United States)

    Kolahi, Jafar; Fazilati, Mohamad; Kadivar, Mahdi

    2009-10-01

    Most soft drinks contain high concentration of simple carbohydrates and have a pH of 3 or even lower. Therefore, they are harmful for tooth structure. A tooth friendly soft drink (T.F.S.D) should have the following characteristics and elements; fluoride (approximately 1 ppm), casein phosphopeptide-amorphous calcium phosphate (2%), xylitol (4-6g/serving), tea polyphenols (2-4 mg/ml), cranberry extract (250 mg/ml of the flavonoids quercetin and myricetin), sugar free, pH close to 5.5 and super oxygenation (240,000 ppm) vs. carbonation. T.F.S.D can be packaged in a container which gaseous oxygen is dissolved in a liquid in the form of bubbles. However, looking at opportunities for so-called sophisticated soft drinks, T.F.S.D will be an example for a functional and health oriented soft drink.

  13. Non-statistical decay and $\\alpha$-correlations in the $^{12}$C+$^{12}$C fusion-evaporation reaction at 95 MeV

    CERN Document Server

    Morelli, L; D'Agostino, M; Gulminelli, F; Bruno, M; Abbondanno, U; Appannababu, S; Barlini, S; Bini, M; Casini, G; Cinausero, M; Degerlier, M; Fabris, D; Gelli, N; Gramegna, F; Kravchuk, V L; Marchi, T; Pasquali, G; Piantelli, S; Valdré, S; Raduta, Ad R

    2014-01-01

    Multiple alpha coincidence and correlations are studied in the reaction $^{12}$C+$^{12}$C at 95 MeV for fusion-evaporation events completely detected in charge. Two specific channels with Carbon and Oxygen residues in coincidence with $\\alpha$-particles are addressed, which are associated with anomalously high branching ratios with respect the predictions by Hauser-Feshbach calculations. Triple alpha emission appears kinematically compatible with a sequential emission from a highly excited Mg. The phase space distribution of $\\alpha$-$\\alpha$ coincidences suggests a correlated emission from a Mg compound, leaving an Oxygen residue excited above the threshold for neutron decay. These observations indicate a preferential $\\alpha$ emission of $^{24}$Mg at excitation energies well above the threshold for $6-\\alpha$ decay.

  14. Antimony uptake by Zea mays (L.) and Helianthus annuus (L.) from nutrient solution.

    Science.gov (United States)

    Tschan, Martin; Robinson, Brett; Schulin, Rainer

    2008-04-01

    We investigated the extent of Sb uptake by maize (Zea mays) and sunflower (Helianthus annuus) from nutrient solutions containing concentrations from 3 to 24 mg/L of potassium antimonate, with the aim of determining the potential of Sb to enter the food chain. The maximum shoot Sb concentrations in Z. mays and H. annuus were 41 mg/kg and 77 mg/kg dry weight, respectively. There was no significant difference in Sb uptake between species. The average bioaccumulation coefficients (the plant/solution concentration quotients) were 1.02 and 1.93 for Z. mays and H. annuus, respectively. Phosphate addition did not affect plant growth or Sb uptake. Antimony uptake by both Z. mays and H. annuus is unlikely to pose a health risk to animals and humans.

  15. Alignment of wave functions for angular momentum projection

    CERN Document Server

    Taniguchi, Yasutaka

    2016-01-01

    Angular momentum projection is used to obtain eigen states of angular momentum from general wave functions. Multi-configuration mixing calculation with angular momentum projection is an important microscopic method in nuclear physics. For accurate multi-configuration mixing calculation with angular momentum projection, concentrated distribution of $z$ components $K$ of angular momentum in the body-fixed frame ($K$-distribution) is favored. Orientation of wave functions strongly affects $K$-distribution. Minimization of variance of $\\hat{J}_z$ is proposed as an alignment method to obtain wave functions that have concentrated $K$-distribution. Benchmark calculations are performed for $\\alpha$-$^{24}$Mg cluster structure, triaxially superdeformed states in $^{40}$Ar, and Hartree-Fock states of some nuclei. The proposed alignment method is useful and works well for various wave functions to obtain concentrated $K$-distribution.

  16. Extraction and isolation of dictamnine, obacunone and fraxinellone from Dictamnus dasycarpus Turcz. by supercritical fluid extraction and high-speed counter-current chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Daijie; Lin, Yunliang; Lin, Xiaojing; Geng, Yanling; Wang, Xiao, E-mail: wxjn1998@126.com [Process Control Research Center of TCM. Shandong Academy of Sciences. Shandong Analysis and Test Center (China); Zhang, Jinjie [College of Biosystems Engineering and Food Science, Zhejiang University (China); Qiu, Jiying [Institute of Agro-Food Science and Technology, Shandong Academy of Agricultural Science, Shandong (China)

    2012-07-01

    Supercritical fluid extraction was used to extract active compounds from the Chinese traditional medicinal D. dasycarpus under the pressure of 30 MPa and temperature of 45 degree C. Further separation and purification was established by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:0.8:1.3:0.9, volume ratio). The separation yielded a total of 47 mg of dictamnine, 24 mg of obacunone and 83 mg of fraxinellone from 1.0 g of the crude extract in one step separation with the purity of 99.2, 98.4 and 99.0%, respectively, as determined by HPLC. The chemical structures of these compounds were identified by ESI-MS, IR, 1H-NMR and {sup 13}C-NMR. (author)

  17. Effect of copper carbonate and zinc oxide applied to seeds on copper and zinc uptake by maize seedlings

    Directory of Open Access Journals (Sweden)

    Marcos Altomani Neves Dias

    2016-01-01

    Full Text Available ABSTRACT Seed treatment is an interesting alternative to deliver micronutrients to field crops. The aim of this study was to investigate the uptake of Cu and Zn by maize seedlings, with the application of the water-insoluble sources copper carbonate and zinc oxide as seed treatment. Treatments were composed of a control (untreated seeds, five doses of copper (0.14, 0.28, 0.56, 1.12 and 2.24 mg Cu∙seed–1 and zinc (0.55, 1.10, 2.20, 4.40 and 8.80 mg Zn∙seed–1 as well as five doses of copper and zinc combined (0.14, 0.28, 0.56, 1.12 and 2.24 mg Cu∙seed–1; 0.55, 1.10, 2.20, 4.40 and 8.80 mg Zn∙seed–1. Plants were cultivated in sand, under greenhouse conditions and, at the two-leaf stage (15 days, the root and shoot tissues dry mass and concentration of Cu and Zn were determined, which allowed to calculate accumulation and uptake efficiency of these micronutrients by maize plants. Seed treatment with copper carbonate and zinc oxide increased both root and shoot concentration and accumulation of Cu and Zn in maize seedlings, with two fully expanded leaves. Cu tended to accumulate in roots, while Zn was more evenly distributed among roots and shoots. Combined application of copper carbonate and zinc oxide resulted in lower uptake of both Cu and Zn by maize if compared to individual applications, with Cu uptake reduced in a higher extent.

  18. MAGNESIUM ISOTOPE EVIDENCE FOR SINGLE STAGE FORMATION OF CB CHONDRULES BY COLLIDING PLANETESIMALS

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, Mia B.; Schiller, Martin; Krot, Alexander N.; Bizzarro, Martin [Centre for Star and Planet Formation, Natural History Museum of Denmark, University of Copenhagen, Copenhagen DK-1350 (Denmark)

    2013-10-10

    Chondrules are igneous spherical objects preserved in chondritic meteorites and believed to have formed during transient heating events in the solar protoplanetary disk. Chondrules present in the metal-rich CB chondrites show unusual chemical and petrologic features not observed in other chondrite groups, implying a markedly distinct formation mechanism. Here, we report high-precision Mg-isotope data for 10 skeletal olivine chondrules from the Hammadah al Hamra 237 (HH237) chondrite to probe the formation history of CB chondrules. The {sup 27}Al/{sup 24}Mg ratios of individual chondrules are positively correlated to their stable Mg-isotope composition (μ{sup 25}Mg), indicating that the correlated variability was imparted by a volatility-controlled process (evaporation/condensation). The mass-independent {sup 26}Mg composition (μ{sup 26}Mg*) of chondrules is consistent with single stage formation from an initially homogeneous magnesium reservoir if the observed μ{sup 25}Mg variability was generated by non-ideal Rayleigh-type evaporative fractionation characterized by a β value of 0.5142, in agreement with experimental work. The magnitude of the mass-dependent fractionation (∼300 ppm) is significantly lower than that suggested by the increase in {sup 27}Al/{sup 24}Mg values, indicating substantial suppression of isotopic fractionation during evaporative loss of Mg, possibly due to evaporation at high Mg partial pressure. Thus, the Mg-isotope data of skeletal chondrules from HH237 are consistent with their origin as melts produced in the impact-generated plume of colliding planetesimals. The inferred μ{sup 26}Mg* value of –3.87 ± 0.93 ppm for the CB parent body is significantly lower than the bulk solar system value of 4.5 ± 1.1 ppm inferred from CI chondrites, suggesting that CB chondrites accreted material comprising an early formed {sup 26}Al-free component.

  19. Disease Caused by Chemical and Physical Agents

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    2007141 Toxicity of combination of fluoride and aluminum on rat embryos in vitro. CHEN Li(陈丽), et al. Dept Toxicol, Public Health Coll, Lanzhou Univ, Lanzhou 730000. Chin J Endemiol 2007;26(2):133-138. Objective To explore developmental toxicity and mechanism of combination of fluoride and aluminum to embryos of SD rat. Methods Embryos of SD rat on day 9.5 of gestation were explanted and cultured in a whole-embryo culture system exposed to a series of doses of fluoride and aluminum (F + Al), which were (0 + 0), (5.0 + 0), (5.0 + 1.2), (5.0 + 2.4), (10.0 + 0), (10.0 + 1.2); (10.0 + 2.4), (0 + 1.2) and (0 + 2.4) mg/L. After 48 h of culture, yolk sac diameter, crown-rump length, head length and dry weight of each viable embryo were evaluated by Browns morphological scoring system. Factorial experimental analysis of 3×3 was used to analyze the types of combined action. Results When exposed to both F and Al, yolk sac diameter, crown-rump length and dry weight affected each other (F=29.75,P<0. 01 ), especially with the consistent increase of Al. Every morphogenetic differentiation index has alternate action (P<0.05). Comparison of the data in groups of F + Al of (10.0 + 2.4)mg/L to (10.0 + 0)mg/L showed that Al had antagonism to teratogenic toxicity induced by fluoride. Conclusion Both fluoride and aluminum are developmental toxicant and dysmorphogent to rats. Aluminum partially antagonizes developmental toxicity induced by fluoride on whole embryo culture.

  20. Vancomycin Serum Concentration Monitoring and Clinical Application%万古霉素血药浓度监测及临床应用

    Institute of Scientific and Technical Information of China (English)

    孙敬英; 张玉梅

    2015-01-01

    目的:探讨临床应用万古霉素血药浓度的监测情况。方法收集2010年1月至2011年1月期间应用万古霉素并对血药浓度进行监测的30例患者资料,对有关指标进行统计分析。结果应用万古霉素患者的有效率达63.3%;测得万古霉素血药浓度峰值<24 mg/L的占60.0%,血药浓度谷值<4 mg/L的占53.3%;治疗后患者肾功能异常为13.3%。结论临床万古霉素应用量及其血药浓度均较小,应结合血药浓度实际监测情况,进行针对性给药。%Objective To investigate the clinical application of vancomycin in blood concentration monitoring. Methods The clinical data of 30 patients with col ected in 2010 January to 2011 January during the application of vancomycin and the blood drug concentrations were monitored.Results The measured peak vancomycin serum concentration less than 24 mg/L for 60.0%,val ey value of less than 4 mg/L for 53.3%;after treatment patients have abnormal renal function 13.3%.Conclusion The blood concentration of vancomycin and its clinical application are smal er,should be combined with the blood concentration monitoring of practical,targeted drug.

  1. The selective dopamine D₃ receptor antagonist SB-277011A attenuates drug- or food-deprivation reactivation of expression of conditioned place preference for cocaine in male Sprague-Dawley rats.

    Science.gov (United States)

    Ashby, Charles R; Rice, Onarae V; Heidbreder, Christian A; Gardner, Eliot L

    2015-06-01

    We determined the effect of the selective dopamine D3 receptor antagonist SB-277011A on reactivation of conditioned place preference (CPP) to cocaine elicited by priming injections of cocaine or exposure to food deprivation stress (21 h) in male Sprague-Dawley rats. Animals paired with the cocaine-associated chamber displayed a robust and consistent CPP response. This CPP was extinguished after repeated pairings of the conditioned stimuli (cocaine-paired chamber contextual cues) in the absence of the unconditioned stimulus (cocaine). Twenty-four hours later, the administration of 5 mg kg(-1) i.p. of cocaine (immediately before the test) or exposure to 21 h of food deprivation reactivated the expression of the cocaine-induced CPP. In contrast, administration of 1 ml kg(-1) i.p. of vehicle did not reactivate the CPP response. Administration of the selective dopamine D3 receptor antagonist SB-277011A (3-24 mg kg(-1) i.p.) 30 min before cocaine administration on the test day produced a significant attenuation of CPP reactivation. Reactivation of the CPP response produced by food deprivation was also significantly attenuated by SB-277011A (6 or 12 mg kg(-1) i.p.) given 30 min before the test session. SB-277011A (12 or 24 mg kg(-1) i.p.) did not itself produce reactivation of the CPP response. Overall, these results suggest that the reactivation of the incentive value of drug-associated cues by cocaine or food deprivation is attenuated by selective antagonism of D3 receptors. © 2015 Wiley Periodicals, Inc.

  2. The Dose-response of Intrathecal Ropivacaine Co-administered with Sufentanil for Cesarean Delivery under Combined Spinal-epidural Anesthesia in Patients with Scarred Uterus

    Institute of Scientific and Technical Information of China (English)

    Fei Xiao; Wen-Ping Xu; Yin-Fa Zhang; Lin Liu; Xia Liu; Li-Zhong Wang

    2015-01-01

    Background:Spinal anesthesia is considered as a reasonable anesthetic option in lower abdominal and lower limb surgery.This study was to determine the dose-response of intrathecal ropivacaine in patients with scarred uterus undergoing cesarean delivery under combined spinal-epidural anesthesia.Methods:Seventy-five patients with scarred uterus undergoing elective cesarean delivery under combined spinal-epidural anesthesia were enrolled in this randomized,double-blinded,dose-ranging study.Patients received 6,8,10,12,or 14 mg intrathecal hyperbaric ropivacaine with 5 μg sufentanil.Successful spinal anesthesia was defined as a T4 sensory level achieved with no need for epidural supplementation.The 50% effective dose (ED50) and 95% effective dose (ED95) were calculated with a logistic regression model.Results:ED50 and ED95 ofintrathecal hyperbaric ropivacaine for patients with scarred uterus undergoing cesarean delivery under combined spinal-epidural anesthesia (CSEA) were 8.28 mg (95% confidence interval [CI]:2.28-9.83 mg) and 12.24 mg (95% CI:10.53-21.88 mg),respectively.Conclusion:When a CSEA technique is to use in patients with scarred uterus for an elective cesarean delivery,the ED50 and ED95 of intrathecal hyperbaric ropivacaine along with 5 μg sufentanil were 8.28 mg and 12.24 mg,respectively.In addition,this local anesthetic is unsuitable for emergent cesarean delivery,but it has advantages for ambulatory patients.

  3. Preparative Separation of Two glycosides from Swertia Mussotti by High-Speed Counter-Current Chromatography%高速逆流色谱分离制备川西獐牙菜中两种苷类化合物

    Institute of Scientific and Technical Information of China (English)

    陈涛; 贾静; 王萍; 尤进茂; 刘永军; 李玉林

    2012-01-01

    A high performance method for isolation and purification of two glycosides from Swertia mussotti was successfully established by utilizing high-speed counter-current chromatography ( HSCCC). Separation was performed with a two-phase solvent system composed of n-butanol-chloroform-methanol-water (3.4:8:5 :6,v/v). 1-O-primevenosyl-3,7, 8-trimethoxyxanthone (11 mg) and isoorientin (24 mg) were isolated and purified in one-step elution from 100 mg crude sample under the conditions of a flow rate 1.5 mL/min in the initial 210 min followed by 2.5 mL/min,800 r/min and the detection wavelength of 254 run. HPLC analysis showed that the purity of two compounds was over 99%. Their chemical structures were confirmed by UV,1H- and 13C NMR.%采用高速逆流色谱从川西獐牙菜中分离制备了两种高纯度苷类化合物.以正丁醇-氯仿-甲醇-水(3.4∶8∶5∶6,v/v)为溶剂系统,主机转速为800 rpm,流速:O~210 min,1.5mL/min;210 ~360m in,2.5 mL/min,检测波长254 nm的条件下进行分离制备,在360 min内从100 mg样品中一步分离制备得到1-O-樱草糖-3,7,8-三甲氧基(口山)酮(Ⅰ,11 mg)和异荭草苷(Ⅱ,24 mg).经HPLC检测,两个化合物的纯度均在99%以上,结构由UV、1H和13C NMR鉴定.

  4. Impact of Different e-Cigarette Generation and Models on Cognitive Performances, Craving and Gesture: A Randomized Cross-Over Trial (CogEcig)

    Science.gov (United States)

    Caponnetto, Pasquale; Maglia, Marilena; Cannella, Maria Concetta; Inguscio, Lucio; Buonocore, Mariachiara; Scoglio, Claudio; Polosa, Riccardo; Vinci, Valeria

    2017-01-01

    Introduction: Most electronic-cigarettes (e-cigarette) are designed to look like traditional cigarettes and simulate the visual, sensory, and behavioral aspects of smoking traditional cigarettes. This research aimed to explore whether different e-cigarette models and smokers' usual classic cigarettes can impact on cognitive performances, craving and gesture. Methods: The study is randomized cross-over trial designed to compare cognitive performances, craving, and gesture in subjects who used first generation electronic cigarettes, second generation electronic cigarettes with their usual cigarettes. (Trial registration: ClinicalTrials.gov number NCT01735487). Results: Cognitive performance was not affected by “group condition.” Within-group repeated measures analyses showed a significant time effect, indicating an increase of participants' current craving measure in group “usual classic cigarettes (group C),” “disposable cigalike electronic cigarette loaded with cartridges with 24 mg nicotine (group H), second generation electronic cigarette, personal vaporizer model Ego C, loaded with liquid nicotine 24 mg (group E). Measures of gesture not differ over the course of the experiment for all the products under investigation Conclusion: All cognitive measures attention, executive function and working memory are not influenced by the different e-cigarette and gender showing that in general electronics cigarettes could become a strong support also from a cognitive point of view for those who decide to quit smoking. It seems that not only craving and other smoke withdrawal symptoms but also cognitive performance is not only linked to the presence of nicotine; this suggests that the reasons behind the dependence and the related difficulty to quit smoking needs to be looked into also other factors like the gesture. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT01735487. PMID:28337155

  5. Probing the Statistical Decay and α-clustering effects in 12C + 12C and 14N + 10B reactions

    Science.gov (United States)

    Morelli, L.; Baiocco, G.; D'Agostino, M.; Bruno, M.; Gulminelli, F.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gramegna, F.; Marchi, T.; Barlini, S.; Bini, M.; Casini, G.; Gelli, N.; Lopez, A.; Pasquali, G.; Piantelli, S.; Valdrè, S.

    2014-03-01

    An experimental campaign has been undertaken at Laboratori Nazionali di Legnaro (LNL INFN), Italy, in order to progress in our understanding of the statistical properties of light nuclei at excitation energies above particle emission threshold, by measuring exclusive data from fusion-evaporation reactions. On the experimental side, a first reaction: 12C+12C at 95 MeV beam energy has been measured, using the GARFIELD + Ring Counter (RCo) apparatuses. Fusion-evaporation events have been exclusively selected out of the entire data set. The comparison to a dedicated Hauser-Feshbach calculation allows us to give constraints on the nuclear level density at high excitation energy for light systems ranging from C up to Mg. Out-of-equilibrium aα emission has been evidenced and attributed both to an entrance channel effect (favoured by the cluster nature of reaction partners), and, in more dissipative events, to the persistence of cluster correlations well above the 24Mg threshold for 6 α's decay. In order to study the same 24Mg compound nucleus at similar excitation energy with respect to this first reaction a new measurement, 14N + 10B at 5.7 A.MeV, was performed at LNL laboratories with the same experimental setup. The comparison between the two systems would allow us to further constrain the level density of light nuclei in the mass-excitation energy range of interest. In this perspective, deviations from a statistical behaviour can be used as a tool to get information on nuclear clustering, both in the ground-state for projectile and target and in the hot source formed in the collision.

  6. Probing the Statistical Decay and α-clustering effects in 12C + 12C and 14N + 10B reactions

    Directory of Open Access Journals (Sweden)

    Morelli L.

    2014-03-01

    Full Text Available An experimental campaign has been undertaken at Laboratori Nazionali di Legnaro (LNL INFN, Italy, in order to progress in our understanding of the statistical properties of light nuclei at excitation energies above particle emission threshold, by measuring exclusive data from fusion-evaporation reactions. On the experimental side, a first reaction: 12C+12C at 95 MeV beam energy has been measured, using the GARFIELD + Ring Counter (RCo apparatuses. Fusion-evaporation events have been exclusively selected out of the entire data set. The comparison to a dedicated Hauser-Feshbach calculation allows us to give constraints on the nuclear level density at high excitation energy for light systems ranging from C up to Mg. Out-of-equilibrium aα emission has been evidenced and attributed both to an entrance channel effect (favoured by the cluster nature of reaction partners, and, in more dissipative events, to the persistence of cluster correlations well above the 24Mg threshold for 6 α’s decay. In order to study the same 24Mg compound nucleus at similar excitation energy with respect to this first reaction a new measurement, 14N + 10B at 5.7 A.MeV, was performed at LNL laboratories with the same experimental setup. The comparison between the two systems would allow us to further constrain the level density of light nuclei in the mass-excitation energy range of interest. In this perspective, deviations from a statistical behaviour can be used as a tool to get information on nuclear clustering, both in the ground-state for projectile and target and in the hot source formed in the collision.

  7. Maintenance dose of warfarin in sheep and effect of diet: a preliminary report.

    Science.gov (United States)

    Sasaki, Takashi; Tsuda, Shoichi; Trujillo, Mario; Kirk Riemer, R; Reinhartz, Olaf

    2012-02-01

    Sheep models are widely used to evaluate the feasibility of various cardiac assist devices. Anticoagulation therapy postoperatively, however, is seldomly reported on. Continuous heparin infusion is often used, but is cumbersome due to long-term line management with the risk of infection and dislodgement. We contemplated using warfarin instead and started a pilot dose-finding study. Three sheep were given oral warfarin between 0.1 and 0.3 mg/kg/day. Prothrombin time was monitored and INR was calculated daily. If the INR did not reach a target of 2.5-3.5, warfarin dose was doubled. We found that sheep required a dose of warfarin between 1.6 and 2.4 mg/kg/day to raise the INR to the target zone. In a subsequent study to evaluate the effect of diet on INR in sheep, three sheep were fed alfalfa hay or alfalfa pellets in a crossover design. All the animals were given warfarin at the dose of 1.6 mg/kg. The diet was switched when the INR reached the target zone of 2.5-3.5. Hay-fed animals reached the target INR on days 6 and 7. On the other hand, pellet-fed animals did not reach the target value by day 7 with the initial dose and required 2.4 mg/kg of warfarin to achieve the goal. Hay raised the INR faster and higher than pellets with the same warfarin dose. Hay may be advantageous when using oral warfarin therapy in sheep.

  8. Oral bioavailability of cyclotrimethylenetrinitramine (RDX) from contaminated site soils in rats.

    Science.gov (United States)

    Crouse, Lee C B; Michie, Mark W; Major, Michael A; Leach, Glenn J; Reddy, Gunda

    2008-01-01

    Cyclotrimethylenetrinitramine (RDX), a commonly used military explosive, was detected as a contaminant of soil and water at Army facilities and ranges. This study was conducted to determine the relative oral bioavailability of RDX in contaminated soil and to develop a method to derive bioavailability adjustments for risk assessments using rodents. Adult male Sprague-Dawley rats preimplanted with femoral artery catheters were dosed orally with gelatin capsules containing either pure RDX or an equivalent amount of RDX in contaminated soils from Louisiana Army Ammunition Plant (LAAP) (2300 microg/g of soil) or Fort Meade (FM) (670 microg/g of soil). After dosing rats, blood samples were collected from catheters at 2-h intervals (2, 4, 6, 8, 10, and 12) and at 24 and 48 h. RDX levels in the blood were determined by gas chromatography. The results show that the peak absorption of RDX in blood was 6 h for neat RDX (1.24 mg/kg) and for RDX from contaminated soil (1.24 mg/kg) of LAAP. Rats dosed with RDX-contaminated FM soil (0.2 mg/kg) showed peak levels of RDX in blood at 6 h, whereas their counterparts that received an identical dose (0.2 mg/kg) of neat RDX showed peak absorption at 4 h. The blood levels of absorbed RDX from LAAP soil were about 25% less than for neat RDX, whereas the bioavailability of RDX from FM soils was about 15% less than that seen in rats treated with neat RDX (0.2 mg/kg). The oral bioavailability in rats fed RDX in LAAP soil and the FM soil was reduced with the neat compound but decrease in bioavailability varied with the soil type.

  9. Determination of the content of amygdalin Baibu Zhike syrup by HPLC%HPLC法测定百部止咳糖浆中苦杏仁苷的含量

    Institute of Scientific and Technical Information of China (English)

    李月琴; 周九兰

    2014-01-01

    Objective To establish a method for determination of amygdalin Baibu Zhike syrup. Methods Using HPLC method, the column was KromasiC18 (5μm,4.6mm ×250mm),mobile phase of methanol -water (20∶80),the column temperature was 25℃,flow rate of 1.0ml/min.The detection wavelength was 215nm.Results The amygdalin in the range of 0.04~0.24mg/ml good linear relationship (r=0.9995 ),the average recovery was 99.65%. RSD 1.90%.Conclusion The method is accurate,fast,relia-ble,and can be used for content determination of amygdalin Baibu Zhike syrup.%目的:建立百部止咳糖浆中苦杏仁苷的含量测定方法。方法:应用HPLC检测法,色谱柱为Kromasi C18(5μm,4.6mm ×250mm),流动相为甲醇-水(20∶80),柱温25℃,流速1.0ml/min。检测波长215nm。结果:苦杏仁苷在0.04~0.24mg/ml范围内线性关系良好(r=0.9995),平均回收率99.65%。RSD为1.90%。结论:该方法准确、快速、可靠,可用于测定百部止咳糖浆中苦杏仁苷的含量。

  10. Analysis of Conjugated Linoleic Acid Isomers by Gas Chromatography%气相色谱法定量分析共轭亚油酸异构体

    Institute of Scientific and Technical Information of China (English)

    王伟; 杨虹; 杨天奎

    2012-01-01

    Conjugated linoleic acids (CLA) are the positional and geometric isomers of linoleic acid,among them,9 c,11t-CLA and 10 t,12 c-CLA exhibited the stronger biological activity. In this study,a method was developed for the quantitative determination of 9 c, 11t-CLA and 10 t, 12 c-CLA by capillary gas chromatography. The sample of CLA oil was methylated with KOH in methanol.The calculation of results was carried out with external standards. The recovery of 9c, 11t-CLA and,10 t,12 c-CLA was between 97.66%-103.51% ,96.12%-102.48% , respectively. The detection and quantitation limits were separately 2.4 mg/kg and 8 mg/kg.%共轭亚油酸(CLA)是亚油酸的位置和几何异构体.其中9c,11t-CLA和10t,12c-CLA是目前发现生理活性比较强的两种共轭结构.作者使用氢氧化钾甲醇溶液对油脂中的共轭亚油酸甘三酯进行水解和甲酯化,利用毛细管气相色谱进行分离后外标法定量.作者得到共轭亚油酸9c,11t-CLA回收率在97.66%~ 103.51%之间,10t,12c-CLA回收率在96.12%~ 102.48%之间,检出限2.4 mg/kg,定量限8 mg/kg.

  11. Ginkgo biloba extracts attenuate lipopolysaccharide-induced inflammatory responses in acute lung injury by inhibiting the COX-2 and NF-κB pathways.

    Science.gov (United States)

    Yao, Xin; Chen, Nan; Ma, Chun-Hua; Tao, Jing; Bao, Jian-An; Zong-Qi, Cheng; Chen, Zu-Tao; Miao, Li-Yan

    2015-01-01

    In the present study, we analyzed the role of Ginkgo biloba extract in lipopolysaccharide(LPS)-induced acute lung injury (ALI). ALI was induced in mice by intratracheal instillation of LPS. G. biloba extract (12 and 24 mg·kg(-1)) and dexamethasone (2 mg·kg(-1)), as a positive control, were given by i.p. injection. The cells in the bronchoalveolar lavage fluid (BALF) were counted. The degree of animal lung edema was evaluated by measuring the wet/dry weight ratio. The superoxidase dismutase (SOD) and myeloperoxidase (MPO) activities were assayed by SOD and MPO kits, respectively. The levels of inflammatory mediators, tumor necrosis factor-a, interleukin-1b, and interleukin-6, were assayed by enzyme-linked immunosorbent assay. Pathological changes of lung tissues were observed by H&E staining. The levels of NF-κB p65 and COX-2 expression were detected by Western blotting. Compared to the LPS group, the treatment with the G. biloba extract at 12 and 24 mg·kg(-1) markedly attenuated the inflammatory cell numbers in the BALF, decreased NF-κB p65 and COX-2 expression, and improved SOD activity, and inhibited MPO activity. The histological changes of the lungs were also significantly improved. The results indicated that G. biloba extract has a protective effect on LPS-induced acute lung injury in mice. The protective mechanism of G. biloba extract may be partly attributed to the inhibition of NF-κB p65 and COX-2 activation.

  12. Chemical composition, antifeedant, repellent, and toxicity activities of the rhizomes of galangal, Alpinia galanga against Asian subterranean termites, Coptotermes gestroi and Coptotermes curvignathus (Isoptera: Rhinotermitidae).

    Science.gov (United States)

    Abdullah, Fauziah; Subramanian, Partiban; Ibrahim, Halijah; Abdul Malek, Sri Nurestri; Lee, Guan Serm; Hong, Sok Lai

    2015-01-01

    Dual choice bioassays were used to evaluate the antifeedant property of essential oil and methanolic extract of Alpinia galanga (L.) (locally known as lengkuas) against two species of termites, Coptotermes gestroi (Wasmann) and Coptotermes curvignathus (Holmgren) (Isoptera: Rhinotermitidae). A 4-cm-diameter paper disc treated with A. galanga essential oil and another treated with either methanol or hexane as control were placed in a petri dish with 10 termites. Mean consumption of paper discs (miligram) treated with 2,000 ppm of essential oil by C. gestroi was 3.30 ± 0.24 mg and by C. curvignathus was 3.32 ± 0.24 mg. A. galanga essential oil showed significant difference in antifeedant effect, 2,000 ppm of A. galanga essential oil was considered to be the optimum concentration that gave maximum antifeedant effect. The essential oil composition was determined using gas chromatography-mass spectrometry. The major component of the essential oil was 1,8-cineol (61.9%). Antifeedant bioassay using 500 ppm of 1,8-cineol showed significant reduction in paper consumption by both termite species. Thus, the bioactive agent in A. galangal essential oil causing antifeeding activity was identified as 1,8-cineol. Repellent activity shows that 250 ppm of 1,8-cineol caused 50.00 ± 4.47% repellency for C. gestroi, whereas for C. curvignathus 750 ppm of 1,8-cineol was needed to cause similar repellent activity (56.67 ± 3.33%). C. curvignathus is more susceptible compare to C. gestroi in Contact Toxicity study, the lethal dose (LD50) of C. curvignathus was 945 mg/kg, whereas LD50 value for C. gestroi was 1,102 mg/kg. Hence 1,8-cineol may be developed as an alternative control against termite in sustainable agriculture practices.

  13. Uncertainty evaluation for determining concentration of sunset yellow in biscuit by HPLC%液相色谱法测定饼干中日落黄含量的测量不确定度评定

    Institute of Scientific and Technical Information of China (English)

    魏大伟; 程江山; 郑玉芝

    2011-01-01

    A mathematical model for uncertainty evaluation of sunset yellow color content determination in biscuit by HPLC was established. By adopting layer modeling evaluation,the total determining uncertainty was evaluated. The uncertainty of external calibration curve was calculated by the least square method. And the result was revised by the recovery ratio. The results showed that the relative standard uncertainty was 0.618mg/kg, and the expand relative standard uncertainty was l.24mg/kg.%利用外标法测定日落黄含量的公式,建立了一个利用高效液相色谱法测定饼干中日落黄含量结果不确定度评定的数学模型,通过该模型对测量过程中不确定度的来源进行了逐层的分析和合成,对标准曲线的不确定度评定采用了最小二乘法,并通过t检验结果的判断,对结果用加标回收率进行了修正.通过对各变量的分析,计算各变量的不确定度,最后计算得出合成标准不确定度0.618mg/kg,扩展标准不确定度1.24mg/kg.

  14. N-acetylcysteine in agriculture, a novel use for an old molecule: focus on controlling the plant-pathogen Xylella fastidiosa.

    Directory of Open Access Journals (Sweden)

    Lígia S Muranaka

    Full Text Available Xylella fastidiosa is a plant pathogen bacterium that causes diseases in many different crops. In citrus, it causes Citrus Variegated Chlorosis (CVC. The mechanism of pathogenicity of this bacterium is associated with its capacity to colonize and form a biofilm in the xylem vessels of host plants, and there is not yet any method to directly reduce populations of this pathogen in the field. In this study, we investigated the inhibitory effect of N-Acetylcysteine (NAC, a cysteine analogue used mainly to treat human diseases, on X. fastidiosa in different experimental conditions. Concentrations of NAC over 1 mg/mL reduced bacterial adhesion to glass surfaces, biofilm formation and the amount of exopolysaccharides (EPS. The minimal inhibitory concentration of NAC was 6 mg/mL. NAC was supplied to X. fastidiosa-infected plants in hydroponics, fertigation, and adsorbed to organic fertilizer (NAC-Fertilizer. HPLC analysis indicated that plants absorbed NAC at concentrations of 0.48 and 2.4 mg/mL but not at 6 mg/mL. Sweet orange plants with CVC symptoms treated with NAC (0.48 and 2.4 mg/mL in hydroponics showed clear symptom remission and reduction in bacterial population, as analyzed by quantitative PCR and bacterial isolation. Experiments using fertigation and NAC-Fertilizer were done to simulate a condition closer to that normally is used in the field. For both, significant symptom remission and a reduced bacterial growth rate were observed. Using NAC-Fertilizer the lag for resurgence of symptoms on leaves after interruption of the treatment increased to around eight months. This is the first report of the anti-bacterial effect of NAC against a phytopathogenic bacterium. The results obtained in this work together with the characteristics of this molecule indicate that the use of NAC in agriculture might be a new and sustainable strategy for controlling plant pathogenic bacteria.

  15. Orally administered bisphenol a in rainbow trout (Oncorhynchus mykiss): estrogenicity, metabolism, and retention.

    Science.gov (United States)

    Bjerregaard, Poul; Andersen, Sidsel B; Pedersen, Knud L; Pedersen, Søren N; Korsgaard, Bodil

    2007-09-01

    The estrogenic effect of orally administered bisphenol A (BPA) was investigated in a rainbow trout (Oncorhynchus mykiss) test system. Bisphenol A was administered orally to sexually immature rainbow trout every second day for up to 12 d in doses between 1.8 and 258 mg/kg every second day (/2d). Plasma vitellogenin was measured before and during the exposures, and the concentrations of BPA in plasma, liver, and muscle and the plasma concentrations of BPA glucuronic acid (BPAGA) were determined at the end of the experiments. Increases in average plasma vitellogenin levels were seen at oral exposure to 24 mg BPA/kg/2d; the most sensitive fish responded to 9.3 mg/kg/2d. At day 12, the 10, 50, and 90% effective doses for increase in vitellogenin synthesis were 13, 19, and 25 mg/kg/2d, respectively. Bisphenol A could be detected in liver, muscle, and plasma at the end of the exposure, generally in increasing concentrations with increasing doses; liver concentrations generally were higher than muscle concentrations. Four to five hours after the last feeding of doses between 3.6 and 24 mg BPA/kg, plasma BPA concentrations ranged between 400 and 1,200 nM, whereas BPAGA concentrations were between 2- and 10-fold higher. The difference between BPA and BPAGA concentrations increased with increasing BPA dose. Bisphenol A showed little tendency to bioaccumulate in rainbow trout; less than 1% of the total amount of BPA administered orally at doses between 1.8 and 258 mg/ kg/2d over the 10- or 12-d experimental period was retained in muscle and liver at 5 or 24 h after the end of the experiments.

  16. Resorbable polymer microchips releasing BCNU inhibit tumor growth in the rat 9L flank model.

    Science.gov (United States)

    Kim, Grace Y; Tyler, Betty M; Tupper, Malinda M; Karp, Jeffrey M; Langer, Robert S; Brem, Henry; Cima, Michael J

    2007-11-01

    Sustained local delivery of single agents and controlled delivery of multiple chemotherapeutic agents are sought for the treatment of brain cancer. A resorbable, multi-reservoir polymer microchip drug delivery system has been tested against a tumor model. The microchip reservoirs were loaded with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). BCNU was more stable at 37 degrees C within the microchip compared to a uniformly impregnated polymeric wafer (70% intact drug vs. 38%, at 48 h). The half-life of the intact free drug in the microchip was 11 days, which is a marked enhancement compared to its half-life in normal saline and 10% ethanol (7 and 10 min, respectively) [P. Tepe, S.J. Hassenbusch, R. Benoit, J.H. Anderson, BCNU stability as a function of ethanol concentration and temperature, J. Neurooncol. 10 (1991) 121-127; P. Kari, W.R. McConnell, J.M. Finkel, D.L. Hill, Distribution of Bratton-Marshall-positive material in mice following intravenous injections of nitrosoureas, Cancer Chemother. Pharmacol. 4 (1980) 243-248]. A syngeneic Fischer 344 9L gliosarcoma rat model was used to study the tumoricidal efficacy of BCNU delivery from the microchip or homogeneous polymer wafer. A dose-dependent decrease in tumor size was found for 0.17, 0.67, and 1.24 mg BCNU-microchips. Tumors treated with 1.24 mg BCNU-microchips showed significant tumor reduction (p=0.001) compared to empty control microchips at two weeks. The treatment showed similar efficacy to a polymer wafer with the same dosage. The microchip reservoir array may enable delivery of multiple drugs with independent release kinetics and formulations.

  17. Striatal and extrastriatal dopamine D2 receptor occupancy by a novel antipsychotic, blonanserin: a PET study with [11C]raclopride and [11C]FLB 457 in schizophrenia.

    Science.gov (United States)

    Tateno, Amane; Arakawa, Ryosuke; Okumura, Masaki; Fukuta, Hajime; Honjo, Kazuyoshi; Ishihara, Keiichi; Nakamura, Hiroshi; Kumita, Shin-ichiro; Okubo, Yoshiro

    2013-04-01

    Blonanserin is a novel antipsychotic with high affinities for dopamine D(2) and 5-HT(2A) receptors, and it was recently approved for the treatment of schizophrenia in Japan and Korea. Although double-blind clinical trials have demonstrated that blonanserin has equal efficacy to risperidone, and with a better profile especially with respect to prolactin elevation, its profile of in vivo receptor binding has not been investigated in patients with schizophrenia. Using positron emission tomography (PET), we measured striatal and extrastriatal dopamine D(2) receptor occupancy by blonanserin in 15 patients with schizophrenia treated with fixed doses of blonanserin (ie, 8, 16, and 24 mg/d) for at least 4 weeks before PET scans, and in 15 healthy volunteers. Two PET scans, 1 with [(11)C]raclopride for the striatum and 1 with [(11)C]FLB 457 for the temporal cortex and pituitary, were performed on the same day. Striatal dopamine D(2) receptor occupancy by blonanserin was 60.8% (3.0%) [mean (SD)] at 8 mg, 73.4% (4.9%) at 16 mg, and 79.7% (2.3%) at 24 mg. The brain/plasma concentration ratio calculated from D(2) receptor occupancy in the temporal cortex and pituitary was 3.38, indicating good blood-brain barrier permeability. This was the first study to show clinical daily dose amounts of blonanserin occupying dopamine D(2) receptors in patients with schizophrenia. The clinical implications obtained in this study were the optimal therapeutic dose range of 12.9 to 22.1 mg/d of blonanserin required for 70% to 80% dopamine D(2) receptor occupancy in the striatum, and the good blood-brain barrier permeability that suggested a relatively lower risk of hyperprolactinemia.

  18. N-acetylcysteine in agriculture, a novel use for an old molecule: focus on controlling the plant-pathogen Xylella fastidiosa.

    Science.gov (United States)

    Muranaka, Lígia S; Giorgiano, Thais E; Takita, Marco A; Forim, Moacir R; Silva, Luis F C; Coletta-Filho, Helvécio D; Machado, Marcos A; de Souza, Alessandra A

    2013-01-01

    Xylella fastidiosa is a plant pathogen bacterium that causes diseases in many different crops. In citrus, it causes Citrus Variegated Chlorosis (CVC). The mechanism of pathogenicity of this bacterium is associated with its capacity to colonize and form a biofilm in the xylem vessels of host plants, and there is not yet any method to directly reduce populations of this pathogen in the field. In this study, we investigated the inhibitory effect of N-Acetylcysteine (NAC), a cysteine analogue used mainly to treat human diseases, on X. fastidiosa in different experimental conditions. Concentrations of NAC over 1 mg/mL reduced bacterial adhesion to glass surfaces, biofilm formation and the amount of exopolysaccharides (EPS). The minimal inhibitory concentration of NAC was 6 mg/mL. NAC was supplied to X. fastidiosa-infected plants in hydroponics, fertigation, and adsorbed to organic fertilizer (NAC-Fertilizer). HPLC analysis indicated that plants absorbed NAC at concentrations of 0.48 and 2.4 mg/mL but not at 6 mg/mL. Sweet orange plants with CVC symptoms treated with NAC (0.48 and 2.4 mg/mL) in hydroponics showed clear symptom remission and reduction in bacterial population, as analyzed by quantitative PCR and bacterial isolation. Experiments using fertigation and NAC-Fertilizer were done to simulate a condition closer to that normally is used in the field. For both, significant symptom remission and a reduced bacterial growth rate were observed. Using NAC-Fertilizer the lag for resurgence of symptoms on leaves after interruption of the treatment increased to around eight months. This is the first report of the anti-bacterial effect of NAC against a phytopathogenic bacterium. The results obtained in this work together with the characteristics of this molecule indicate that the use of NAC in agriculture might be a new and sustainable strategy for controlling plant pathogenic bacteria.

  19. The low-dose atorvastatin and valsartan combination effectively protects the arterial wall from atherogenic diet-induced impairment in the guinea pig.

    Science.gov (United States)

    Janić, Miodrag; Lunder, Mojca; Zupan, Janja; Černe, Darko; Marc, Janja; Drevenšek, Gorazd; Šabovič, Mišo

    2014-11-15

    New preventive strategies for atherosclerosis are needed. In this study, we tested whether a new therapeutic approach consisting of low-dose treatment with a statin and sartan combination could prevent atherogenic diet-induced impairment of the arterial wall in guinea pigs. Twenty-five Dunkin-Hartley guinea pigs were randomly assigned to five experimental groups: 1) normal diet; 2) atherogenic diet (AD); 3) AD + a low-dose atorvastatin and valsartan combination (5mg/kg/day and 2.4mg/kg/day, respectively); 4) AD + low-dose atorvastatin (5mg/kg/day); 5) AD + low-dose valsartan (2.4mg/kg/day). After 8 weeks of treatment, the animals were killed, blood samples collected and thoracic and abdominal aortas isolated. The atherogenic diet significantly impaired maximal thoracic aorta endothelium-dependent relaxation by 40.1% relative to the normal diet. The low-dose combination, compared to the separate drugs, completely preserved thoracic aorta endothelium-dependent relaxation at the level of the group receiving normal diet. This substantial effect was associated with a significant change in the expression of NOS3 (R=0.93; P=0.0002) and IL1b (R=-0.79; P=0.003) genes. In addition, treatment with the low-dose combination or the separate drugs also prevented atherosclerotic plaque formation. We found that treatment with the low-dose atorvastatin and valsartan combination has the capability to completely protect the arterial wall from atherogenic diet-induced damage in the guinea pig model. Further studies evaluating this new therapeutic approach are desirable.

  20. Preparation and Activity of Antioxidant Peptide from Pine Nuts in Changbai Mountain%长白山松子抗氧化肽制备及活性研究

    Institute of Scientific and Technical Information of China (English)

    冷帅辰; 闵伟红; 吴丹; 王明爽; 刘景圣; 史军花

    2014-01-01

    以长白山松子分离蛋白为原料,采用碱性蛋白酶制备抗氧化肽,通过Box-Behnken中心组合试验确定最佳水解工艺条件为:酶解温度56.5℃、加酶量7822 U/g、底物质量浓度0.021 g/mL、pH 9.0、酶解时间240 min。对该条件制备的抗氧化肽进行活性研究,结果显示随着浓度的升高,松子抗氧化肽在4 mg/mL时对ABTS自由基的清除率和Fe2+螯合率达到100%,16 mg/mL时对DPPH自由基清除率达到80.95%,24 mg/mL时,对羟基自由基清除率达到100%。%In this experiment, pine nut protein isolated was used as raw material, hydrolyzed by Alcalase to prepare antioxidant peptide.Through Box-Behnken method, the optimal hydrolysis conditions were determined as hydrolysis temperature of 56.5℃,Alcalase concentration of 7 822 U/g, substrate mass concentration of 0.021 g/mL, hydrolysis pH of 9 and hydrolysis time of 240 min. A ssess the antioxidant potential, with the increasing of the peptide solution concentration, ferrous ions chelating capacity and scavenging capacities against ABTS were 100%at 4 mg/mL, scavenging capacities against DPPH was 80.95%at 16 mg/mL, scavenging capacities against hydroxyl radical was 100%at 24 mg/mL.

  1. RELICS OF ANCIENT POST-AGB STARS IN A PRIMITIVE METEORITE

    Energy Technology Data Exchange (ETDEWEB)

    Jadhav, M.; Huss, G. R. [Hawai' i Institute of Geophysics and Planetology, University of Hawai' i at Mānoa, Honolulu, HI 96822 (United States); Pignatari, M. [Department of Physics, University of Basel, CH-4056 Basel (Switzerland); Herwig, F. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P5C2 (Canada); Zinner, E. [Laboratory for Space Sciences and the Physics Department, Washington University, St. Louis, MO 63130 (United States); Gallino, R., E-mail: manavi@higp.hawaii.edu [Dipartimento di Fisica Generale, Università di Torino and INAF, Via Pietro Giuria 1, 10125 Torino (Italy)

    2013-11-10

    Graphite is one of the many presolar circumstellar condensate species found in primitive meteorites. While the isotopic compositions of low-density graphite grains indicate an origin in core-collapse supernovae, some high-density grains have extreme isotopic anomalies in C, Ca, and Ti, which cannot be explained by envelope predictions of asymptotic giant branch (AGB) stars or theoretical supernova models. The Ca and Ti isotopic anomalies, however, match the predictions of He-shell abundances in AGB stars. In this study, we show that the C, Ca, and Ti isotopic anomalies are consistent with nucleosynthesis predictions of the H-ingestion phase during a very late thermal pulse (VLTP) event in post-AGB stars. The low {sup 12}C/{sup 13}C isotopic ratios in these grains are a result of abundant {sup 12}C efficiently capturing the protons that are being ingested during the VLTP. Very high neutron densities of ∼10{sup 15} cm{sup –3}, typical of the i-process, are achieved during this phase in post-AGB stars. The large {sup 42,43,44}Ca excesses in some graphite grains are indicative of neutron capture nucleosynthesis during VLTP. The comparison of VLTP nucleosynthesis calculations to the graphite data also indicate that apparent anomalies in the Ti isotopic ratios are due to large contributions from {sup 46,48}Ca, which cannot be resolved from the isobars {sup 46,48}Ti during the measurements. We conclude that presolar graphite grains with moderate to extreme Ca and Ti isotopic anomalies originate in post-AGB stars that suffer a VLTP.

  2. Calcium isotopic compositions as tracers of vegetation activity in boreal permafrost ecosystems (Kulingdakan watershed, Central Siberia)

    Science.gov (United States)

    Bagard, M.; Schmitt, A.; Chabaux, F. J.; Viers, J.; Pokrovsky, O. S.; Prokushkin, A. S.; Stille, P.; Dupré, B.

    2010-12-01

    In this work, we propose to investigate the geochemical potential of calcium isotopic fractionations in a forested boreal watershed to trace the impact of vegetation activity. This is the first study carried out in a geographical area characterized by deep and continuous permafrost. For this survey, we measured Ca and Sr isotopic compositions in the different compartments (stream waters, soil solutions, precipitations, rock, soils and soil leachates, vegetation) of a 4,100 ha Siberian watershed, the Kulingdakan watershed (Putorana Plateau, Central Siberia). Our results show that the activity of the vegetation is the only process that fractionates significantly calcium isotopes within the watershed. Indeed, Ca uptake by plants and its subsequent storage in larch tree organs favours 40Ca relatively to 44Ca. Vegetation decomposition releases light δ44/40Ca that affects calcium isotopic compositions of soil solution and soil exchangeable fractions. However, this biological impact is significant only for the South-facing slope of the watershed. Indeed, soil pools from the North-facing slope present no imprint of organic matter degradation in their δ44/40Ca signatures. Furthermore, the major difference between South- and North- facing slopes lies in the importance of the vegetation and its decomposition rate. Thus, we propose that in boreal permafrost areas with limited runoff, the available stock of biomass is critical to induce or not a significant vegetation impact on the calcium isotopic compositions in the soil-water system. As a consequence, the study of preserved calcium isotopic compositions in paleosoil exchangeable phases might bring relevant information on the evolution of biological activity at the watershed scale.

  3. Mineralogical Study of Zard Koh and Kulli Koh Iron Ore Deposits of Pakistan

    Directory of Open Access Journals (Sweden)

    SULTAN AHMED KHOSO

    2017-10-01

    Full Text Available Zard Koh and Kulli Koh are two recently discovered iron ore deposits, existing in the Chagai district, Balochistan, Pakistan. PSM (Pakistan Steel Mill Limited is interested to utilize these ore deposits at priority. Purpose of the present study was to assess the mineralogy of the Zard Koh and Kulli Koh iron ore deposits, as it plays a vital role in the selection of an appropriate processing method. The mineralogical study of ore deposits was carried out by XRD (X-Ray Diffraction, XRF (X-Ray Fluorescence, SEM (Scanning Electron Microscope attached with EDS (Energy Dispersive Spectroscope and SM (Stereomicroscope techniques. Results indicated that the Zard Koh ore is mainly composed of 60.15% maghemite, 23.57% pyrite, 4.07% chlorite, 10.30% grossular and 1.65% admontite minerals. The chemical analysis revealed that Zard Koh iron ore contains an average of 54.27% Fe, 12.73% S, 8.70% Si, 3.07% Al, 4.07% Ca, and 2.16% Mg. Similarly, the mineralogical study of the Kulli Koh iron ore indicated that, ore is containing 51.16% hematite, 29.24% quartz, 8.89% dravite, and 8.76% kaolinite minerals. Elemental analysis of different samples indicated that Kulli Koh iron ore contains an average composition of 40.23% Fe, 20.67% Si, 3.44% Ca, 3.81% Al and 3.25% Mg. Mineralogical study of the Zard Koh and Kulli Koh iron ore deposits suggested that these ore deposits can be beneficiated costeffectively by using magnetic separation techniques.

  4. 87Sr/86Sr isotope ratio measurements by laser ablation multicollector inductively coupled plasma mass spectrometry: Reconsidering matrix interferences in bioapatites and biogenic carbonates

    Science.gov (United States)

    Irrgeher, Johanna; Galler, Patrick; Prohaska, Thomas

    2016-11-01

    This study is dedicated to the systematic investigation of the effect of interferences on Sr isotopic analyses in biological apatite and carbonate matrices using laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC ICP-MS). Trends towards higher 87Sr/86Sr ratios for LA-MC ICP-MS compared to solution-nebulization based MC ICP-MS when analysing bioapatite matrices (e.g. human teeth) and lower ratios in case of calcium carbonates (e.g. fish ear stones) were observed. This effect can be related to the presence of significant matrix-related interferences such as molecular ions (e.g. (40Ca-31P-16O)+, (40Ar-31P-16O)+, (42Ca-44Ca)+, (46Ca40Ar)+) as well as in many cases concomitant atomic ions (e.g. 87Rb+, 174Hf2 +). Direct 87Sr/86Sr ratio measurements in Ca-rich samples are conducted without the possibility of prior sample separation, which can be accomplished routinely for solution-based analysis. The presence of Ca-Ar and Ca-Ca molecular ion interferences in the mass range of Sr isotopes is shown using the mass resolving capabilities of a single collector inductively coupled plasma sector field mass spectrometer operated in medium mass resolution when analysing bioapatites and calcium carbonate samples. The major focus was set on analysing human tooth samples, fish hard parts and geological carbonates. Potential sources of interferences were identified and corrected for. The combined corrections of interferences and adequate instrumental isotopic fractionation correction procedures lead to accurate data even though increased uncertainties have to be taken into account. The results are discussed along with approaches presented in literature for data correction in laser ablation analysis.

  5. Study of selective heating at ion cyclotron resonance for the plasma separation process

    Science.gov (United States)

    Compant La Fontaine, A.; Pashkovsky, V. G.

    1995-12-01

    The plasma separation process by ion cyclotron resonance heating (ICRH) is studied both theoretically and experimentally on two devices: the first one called ERIC (Ion Cyclotron Resonance Experiment) at Saclay (France) [P. Louvet, Proceedings of the 2nd Workshop on Separation Phenomena in Liquids and Gases, Versailles, France, 1989, edited by P. Louvet, P. Noe, and Soubbaramayer (Centre d'Etudes Nucléaires de Saclay and Cité Scientifique Parcs et Technopoles, Ile de France Sud, France, 1989), Vol. 1, p. 5] and the other one named SIRENA at the Kurchatov Institute, Moscow, Russia [A. I. Karchevskii et al., Plasma Phys. Rep. 19, 214 (1993)]. The radio frequency (RF) transversal magnetic field is measured by a magnetic probe both in plasma and vacuum and its Fourier spectrum versus the axial wave number kz is obtained. These results are in agreement with the electromagnetic (EM) field calculation model based on resolution of Maxwell equations by a time-harmonic scheme studied here. Various axial boundary conditions models used to compute the EM field are considered. The RF magnetic field is weakly influenced by the plasma while the electric field components are strongly disturbed due to space-charge effects. In the plasma the transversal electric field is enhanced and the kz spectrum is narrower than in vacuum. The calculation of the resonant isotope heating is made by the Runge-Kutta method. The influence of ion-ion collisions, inhomogeneity of the static magnetic field B0, and the RF transversal magnetic field component on the ion acceleration is examined. These results are successfully compared with experiments of a minor isotope 44Ca heating measurements, made with an energy analyzer.

  6. Study of selective heating at ion cyclotron resonance for the plasma separation process

    Energy Technology Data Exchange (ETDEWEB)

    Compant La Fontaine, A. [Direction du Cycle du Combustible/Departement des Procedes d` Enrichissement, Service de Physique, d` Experimentation et d` Analyse, Commissariat a l` Energie Atomique, Centre d` Etudes de Saclay, 91191 Gif-sur-Yvette Cedex (France); Pashkovsky, V.G. [Molecular Physics Institute, RRC Kurchatov Institute 123182, Moscow (Russian Federation)

    1995-12-01

    The plasma separation process by ion cyclotron resonance heating (ICRH) is studied both theoretically and experimentally on two devices: the first one called ERIC (Ion Cyclotron Resonance Experiment) at Saclay (France) [P. Louvet, {ital Proceedings} {ital of} {ital the} 2{ital nd} {ital Workshop} {ital on} {ital Separation} {ital Phenomena} {ital in} {ital Liquids} {ital and} {ital Gases}, Versailles, France, 1989, edited by P. Louvet, P. Noe, and Soubbaramayer (Centre d`Etudes Nucleaires de Saclay and Cite Scientifique Parcs et Technopoles, Ile de France Sud, France, 1989), Vol. 1, p. 5] and the other one named SIRENA at the Kurchatov Institute, Moscow, Russia [A. I. Karchevskii {ital et} {ital al}., Plasma Phys. Rep. {bold 19}, 214 (1993)]. The radio frequency (RF) transversal magnetic field is measured by a magnetic probe both in plasma and vacuum and its Fourier spectrum versus the axial wave number {ital k}{sub {ital z}} is obtained. These results are in agreement with the electromagnetic (EM) field calculation model based on resolution of Maxwell equations by a time-harmonic scheme studied here. Various axial boundary conditions models used to compute the EM field are considered. The RF magnetic field is weakly influenced by the plasma while the electric field components are strongly disturbed due to space-charge effects. In the plasma the transversal electric field is enhanced and the {ital k}{sub {ital z}} spectrum is narrower than in vacuum. The calculation of the resonant isotope heating is made by the Runge--Kutta method. The influence of ion--ion collisions, inhomogeneity of the static magnetic field {ital B}{sub 0}, and the RF transversal magnetic field component on the ion acceleration is examined. These results are successfully compared with experiments of a minor isotope {sup 44}Ca heating measurements, made with an energy analyzer. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  7. Analysis of Mussel Standard Reference Material by Inductively Coupled Plasma Atomic Emission Spectrometry and Inductively Coupled Plasma Mass Spectrometry%电感耦合等离子体光谱和质谱法分析贻贝标准物质

    Institute of Scientific and Technical Information of China (English)

    曹淑琴; 陈杭亭; 曾宪津

    1999-01-01

    采用电感耦合等离子体光谱和质谱法分析了贻贝标准物质,光谱法测定K、Na、Ca、Mg、P、Al、Fe、Zn、Mn和Sr,质谱法测定As、B、Cd、Co、Cr、Cu、Ga、Ge、Mn、Mo、Ni、Pb、De、Sr、U和V.在优化的工作条件下,测定了来自基体元素K、Na、Ca、P、Cl和C的多原子离子39K16O、39K2、40Ar23Na、43Ca16O、42Ca16O、44Ca16O、31P16O2、40Ar35Cl、40Ar37Cl、35Cl16O、37Cl16O和40Ar12C对55Mn、78Se、63Cu、59Co、58Ni、60Ni、75as、77Se、51V、53Cr和52Cr的干扰系数以及HNO3+H2O2(3+2)、HNO3+HClO4(3+0.5)和HNO3+H2SO4(3+0.5)等3种样品消解方法在一些生物重要元素的同位素处产生的表观浓度.光谱法的检出限0.001~0.75 mg/L;质谱法的检出限0.005~1.01μgL.光谱法和质谱法的相对标准偏差分别是2.7%~12.8%和3.4%~24.8%.

  8. ICP-MS with hexapole collision cell for isotope ratio measurements of Ca, Fe, and Se.

    Science.gov (United States)

    Boulyga, S F; Becker, J S

    2001-07-01

    To avoid mass interferences on analyte ions caused by argon ions and argon molecular ions via reactions with collision gases, an rf hexapole filled with helium and hydrogen has been used in inductively coupled plasma mass spectrometry (ICP-MS), and its performance has been studied. Up to tenfold improvement in sensitivity was observed for heavy elements (m > 100 u), because of better ion transmission through the hexapole ion guide. A reduction of argon ions Ar+ and the molecular ions of argon ArX+ (X = O, Ar) by up to three orders of magnitude was achieved in a hexapole collision cell of an ICP-MS ("Platform ICP", Micromass, Manchester, UK) as a result of gas-phase reactions with hydrogen when the hexapole bias (HB) was set to 0 V; at an HB of 1.6 V argon, and argon-based ions of masses 40 u, 56 u, and 80 u, were reduced by approximately four, two, and five orders of magnitude, respectively. The signal-to-noise ratio 80Se/ 40Ar2+ was improved by more than five orders of magnitude under optimized experimental conditions. Dependence of mass discrimination on collision-cell properties was studied in the mass range 10 u (boron) to 238 u (uranium). Isotopic analysis of the elements affected by mass-spectrometric interference, Ca, Fe, and Se, was performed using a Meinhard nebulizer and an ultrasonic nebulizer (USN). The measured isotope ratios were comparable with tabulated values from IUPAC. Precision of 0.26%, 0.19%, and 0.12%, respectively, and accuracy of 0.13% 0.25%, and 0.92%, respectively, was achieved for isotope ratios 44Ca/ 40Ca and 56Fe/57Fe in 10 microg L(-1) solution nebulized by means of a USN and for 78Se/80Se in 100 microg L(-1) solution nebulized by means of a Meinhard nebulizer.

  9. 子宫颈上皮内瘤变120例临床病理分析%Clinical and pathological analysis of 120 cases cervical intraepithelial neoplasia

    Institute of Scientific and Technical Information of China (English)

    陈仲涛; 张英

    2012-01-01

    Objective: To evaluate the diagnosis and differential diagnosis, prognosis and early prevention of cervi-cal intraepithelial neoplasia. Methods: Total of 120 cases of cervical intraepithelial lesions were followed - up, and ob-served the characteristics and classification. Results:The diagnosis of CIN Ⅰ in 12 cases (10% ) ,CIN Ⅱ grade 44 ca-ses (36.7%),CIN Ⅲ 64 cases (53.3%).CIN I -1 grade cervical loop conization 77 cases (64.2%),CIN Ⅲ grade hysterectomy in 43 cases (35.8%). Conclusion: Cervical three - step examination of the cervical CIN is useful to early diagnosis and early treatment and reduce the cervical carcinoma incidence rate and mortality.%目的:探讨子宫颈上皮内瘤变的诊断与鉴别诊断要点、预后及早期防治.方法:收集120例子宫颈上皮内瘤样病变,进行随访,并对光镜下的特点进行观察和分级.结果:诊断CIN Ⅰ级12例(10%),CINⅡ级44例(36.7%),CIN Ⅲ级64例(53.3%).CIN Ⅰ-Ⅲ级官颈环锥切77例(64.2%),CIN Ⅲ级子宫全切43例(35.8%).结论:宫颈三阶梯检查,对宫颈CIN可早诊断,早治疗,减低了宫颈浸润癌的发生率及死亡率.

  10. 任邱球粒陨石

    Institute of Scientific and Technical Information of China (English)

    王道德

    1977-01-01

    March 23, 1916 witnessed the fall of the Renqiu meteorite near the town of Renqin(38°40' N, 116°08' E). This meteorite, weighing about 300gm, was found in 1975 by Peking Astronomical Planelarium. X-ray diffraction analyses and microseopie identification have given: olivine (22% Fa), orthopyroxene (14% FS), pLagiocLase,troilite, kamocite, taenite, whitlockite, chromite. Chemieal analyses reveal: SiO2 40.52,TiO2 0.088, Al2O3 2.41, Cr2O3 0.56, FeO 14.20, MnO 0.46, MgO 24.44, CaO 2.01, Na2O 0.96, K2O 0.12, H2O 0.12, H2O- 0.39, H2O+ 0.38, P2O5 0.20, Fe° 6.71, Ni 1.13, FeS 5.48, Co 0.058, Cu 0.015, Zn 0.005, C 0.17, total 100.31. The modal mineral proportion gives : olivine 41.96%, pyroxene 31.90%, plagioclase 10.01%, orthoclase 0.71%, chromite 0.83%, titanite 0.17%, whitlockite 0.44%, metellie Fe-Ni (kamocite and taenite)7.84% and troilite 5.48%. It is shown from the typically chemical analysis of L-group that the meteorite should be classified as an recrystallized L-6 chondrite.

  11. Development of a method based on inductively coupled plasma-dynamic reaction cell-mass spectrometry for the simultaneous determination of phosphorus, calcium and strontium in bone and dental tissue

    Energy Technology Data Exchange (ETDEWEB)

    De Muynck, David [Ghent University, Department of Analytical Chemistry, Krijgslaan 281-S12, BE-9000 Ghent (Belgium)], E-mail: David.DeMuynck@UGent.be; Vanhaecke, Frank [Ghent University, Department of Analytical Chemistry, Krijgslaan 281-S12, BE-9000 Ghent (Belgium)], E-mail: Frank.Vanhaecke@UGent.be

    2009-05-15

    A method, based on the use of a quadrupole-based inductively coupled plasma-mass spectrometry instrument equipped with a quadrupole-based collision/reaction cell (dynamic reaction cell, DRC), was developed for the simultaneous determination of phosphorus, calcium and strontium in bone and dental (enamel and dentine) tissue. The use of NH{sub 3}, introduced at a gas flow rate of 0.8 mL min{sup -1} in the dynamic reaction cell, combined with a rejection parameter q (RPq) setting of 0.65, allows interference-free determination of calcium via its low-abundant isotopes {sup 42}Ca, {sup 43}Ca and {sup 44}Ca, and of strontium via its isotopes {sup 86}Sr and {sup 88}Sr that are freed from overlap due to the occurrence of ArCa{sup +} and/or Ca{sub 2}{sup +} ions. Also the determination of phosphorus ({sup 31}P, mono-isotopic) was shown to be achievable using the same dynamic reaction cell operating conditions. The bone certified reference materials NIST SRM 1400 Bone Ash and NIST SRM 1486 Bone Meal were used for validation of the measurement protocol that was shown capable of providing accurate and reproducible results. Detection limits of P, Ca and Sr in dental tissue digests were established as 3 {mu}g L{sup -1} for P, 2 {mu}g L{sup -1} for Ca and 0.2 {mu}g L{sup -1} for Sr. This method can be used to simultaneously (i) evaluate the impact of diagenesis on the elemental and isotopic composition of buried skeletal tissue via its Ca/P ratio and (ii) determine its Sr concentration. The measurement protocol was demonstrated as fit-for-purpose by the analysis of a set of teeth of archaeological interest for their Ca/P ratio and Sr concentration.

  12. Are presolar dust grains from novae actually from supernovae?

    Science.gov (United States)

    Nittler, L. R.; Hoppe, P.

    2005-05-01

    Meteorites contain presolar stardust grains that formed in prior generations of stars and exhibit large isotopic anomalies reflecting the nuclear processes that occurred in their individual parent stars. RGB and AGB stars and supernovae are well established as sources of many of these grains. Novae have been proposed as sources for a few SiC and graphite grains with low 12}C/{13C and 14}N/{15N ratios and unusual Si isotopic ratios (Amari et al., ApJ, 551, 1065). We have found three SiC grains from the Murchison meteorite with C and N isotopic ratios similar to the previously-reported putative nova grains. However, the isotopic signatures of Si, Ca, Al and Ti in one of the grains (334-2) clearly indicate a supernova origin, especially excess 28Si correlated with excess 44Ca. The latter signature is attributable to in situ decay of (half-life=50yr) 44Ti. Another 13C- and 15N-rich grain (151-4) has a large 47Ti enrichment. This signature is not expected for nova nucleosynthesis. Thus, the new isotopic data raise the possibility that the grains previously reported to have formed in novae actually formed in supernovae, and that novae have not left a record in the presolar grain populations that have been so far studied. Moreover, the results in grain 334-2 indicate that supernovae contain regions highly enriched in both 13C and 15N. This is not predicted by current models but may bear on the cosmic origin of 15N. This work was funded in part by NASA.

  13. First-in-Human PET/CT Imaging of Metastatic Neuroendocrine Neoplasms with Cyclotron-Produced (44)Sc-DOTATOC: A Proof-of-Concept Study.

    Science.gov (United States)

    Singh, Aviral; van der Meulen, Nicholas P; Müller, Cristina; Klette, Ingo; Kulkarni, Harshad R; Türler, Andreas; Schibli, Roger; Baum, Richard P

    2017-05-01

    (44)Sc is a promising positron emission tomography (PET) radionuclide (T1/2 = 4.04 hours, Eβ+average = 632 keV) and can be made available, using a cyclotron production route, in substantial quantities as a highly pure product. Herein, the authors report on a first-in-human PET/CT study using (44)Sc-DOTATOC prepared with cyclotron-produced (44)Sc. The production of (44)Sc was carried out through the (44)Ca(p,n)(44)Sc nuclear reaction at Paul Scherrer Institut, Switzerland. After separation, (44)Sc was shipped to Zentralklinik Bad Berka, Germany, where radiolabeling was performed, yielding radiochemically pure (44)Sc-DOTATOC. Two patients, currently followed up after peptide receptor radionuclide therapy of metastatic neuroendocrine neoplasms, participated in this proof-of-concept study. Blood sampling was performed before and after application of (44)Sc-DOTATOC. PET/CT acquisitions, performed at different time points after injection of (44)Sc-DOTATOC, allowed detection of even very small lesions on delayed scans. No clinical adverse effects were observed and the laboratory hematological, renal, and hepatic profiles remained unchanged. In this study, cyclotron-produced (44)Sc was used in the clinic for the first time. It is attractive for theranostic application with (177)Lu, (90)Y, or (47)Sc as therapeutic counterparts. (44)Sc-based radiopharmaceuticals will be of particular value for PET facilities without radiopharmacy, to which they can be shipped from a centralized production site.

  14. Magnesium stable isotope ecology using mammal tooth enamel.

    Science.gov (United States)

    Martin, Jeremy E; Vance, Derek; Balter, Vincent

    2015-01-13

    Geochemical inferences on ancient diet using bone and enamel apatite rely mainly on carbon isotope ratios (δ(13)C) and to a lesser extent on strontium/calcium (Sr/Ca) and barium/calcium (Ba/Ca) elemental ratios. Recent developments in nontraditional stable isotopes provide an unprecedented opportunity to use additional paleodietary proxies to disentangle complex diets such as omnivory. Of particular relevance for paleodietary reconstruction are metals present in large quantity in bone and enamel apatite, providing that biologically mediated fractionation processes are constrained. Calcium isotope ratios (δ(44)Ca) meet these criteria but exhibit complex ecological patterning. Stable magnesium isotope ratios (δ(26)Mg) also meet these criteria but a comprehensive understanding of its variability awaits new isotopic data. Here, 11 extant mammal species of known ecology from a single locality in equatorial Africa were sampled for tooth enamel and, together with vegetation and feces, analyzed for δ(26)Mg, δ(13)C, Sr/Ca, and Ba/Ca ratios. The results demonstrate that δ(26)Mg incorporated in tooth enamel becomes heavier from strict herbivores to omnivores/faunivores. Using data from experimentally raised sheep, we suggest that this (26)Mg enrichment up the trophic chain is due to a (26)Mg enrichment in muscle relative to bone. Notably, it is possible to distinguish omnivores from herbivores, using δ(26)Mg coupled to Ba/Ca ratios. The potential effects of metabolic and dietary changes on the enamel δ(26)Mg composition remain to be explored but, in the future, multiproxy approaches would permit a substantial refinement of dietary behaviors or enable accurate trophic reconstruction despite specimen-limited sampling, as is often the case for fossil assemblages.

  15. Characterization of calcium isotopes in natural and synthetic barite

    Science.gov (United States)

    Griffith, E.M.; Schauble, E.A.; Bullen, T.D.; Paytan, A.

    2008-01-01

    The mineral barite (BaSO4) accommodates calcium in its crystal lattice, providing an archive of Ca-isotopes in the highly stable sulfate mineral. Holocene marine (pelagic) barite samples from the major ocean basins are isotopically indistinguishable from each other (??44/40Ca = -2.01 ?? 0.15???) but are different from hydrothermal and cold seep barite samples (??44/40Ca = -4.13 to -2.72???). Laboratory precipitated (synthetic) barite samples are more depleted in the heavy Ca-isotopes than pelagic marine barite and span a range of Ca-isotope compositions, ??44/40Ca = -3.42 to -2.40???. Temperature, saturation state, a Ba2 + / a SO42 -, and aCa2+/aBa2+ each influence the fractionation of Ca-isotopes in synthetic barite; however, the fractionation in marine barite samples is not strongly related to any measured environmental parameter. First-principles lattice dynamical modeling predicts that at equilibrium Ca-substituted barite will have much lower 44Ca/40Ca than calcite, by -9??? at 0 ??C and -8??? at 25 ??C. Based on this model, none of the measured barite samples appear to be in isotopic equilibrium with their parent solutions, although as predicted they do record lower ??44/40Ca values than seawater and calcite. Kinetic fractionation processes therefore most likely control the extent of isotopic fractionation exhibited in barite. Potential fractionation mechanisms include factors influencing Ca2+ substitution for Ba2+ in barite (e.g. ionic strength and trace element concentration of the solution, competing complexation reactions, precipitation or growth rate, temperature, pressure, and saturation state) as well as nucleation and crystal growth rates. These factors should be considered when investigating controls on isotopic fractionation of Ca2+ and other elements in inorganic and biogenic minerals. ?? 2008 Elsevier Ltd.

  16. Cyclotron production of (44)Sc: From bench to bedside.

    Science.gov (United States)

    van der Meulen, Nicholas P; Bunka, Maruta; Domnanich, Katharina A; Müller, Cristina; Haller, Stephanie; Vermeulen, Christiaan; Türler, Andreas; Schibli, Roger

    2015-09-01

    (44)Sc, a PET radionuclide, has promising decay characteristics (T1/2 = 3.97 h, Eβ(+)av = 632 keV) for nuclear imaging and is an attractive alternative to the short-lived (68)Ga (T1/2 = 68 min, Eβ(+)av = 830 keV). The aim of this study was the optimization of the (44)Sc production process at an accelerator, allowing its use for preclinical and clinical PET imaging. (44)CaCO3 targets were prepared and irradiated with protons (~11 MeV) at a beam current of 50 μA for 90 min. (44)Sc was separated from its target material using DGA extraction resin and concentrated using SCX cation exchange resin. Radiolabeling experiments at activities up to 500 MBq and stability tests were performed with DOTANOC by investigating different scavengers, including gentisic acid. Dynamic PET of an AR42J tumor-bearing mouse was performed after injection of (44)Sc-DOTANOC. The optimized chemical separation method yielded up to 2 GBq (44)Sc of high radionuclidic purity. In the presence of gentisic acid, radiolabeling of (44)Sc with DOTANOC was achieved with a radiochemical yield of ~99% at high specific activity (10 MBq/nmol) and quantities which would allow clinical application. The dynamic PET images visualized increasing uptake of (44)Sc-DOTANOC into AR42J tumors and excretion of radioactivity through the kidneys of the investigated mouse. The concept "from-bench-to-bedside" was clearly demonstrated in this extended study using cyclotron-produced (44)Sc. Sufficiently high activities of (44)Sc of excellent radionuclidic purity are obtainable for clinical application, by irradiation of enriched calcium at a cyclotron. This work demonstrates a promising basis for introducing (44)Sc to clinical routine of nuclear imaging using PET. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Batisite, Na2BaTi2(Si4O12)O2, from Inagli massif, Aldan, Russia: crystal-structure refinement and high-temperature X-ray diffraction study

    Science.gov (United States)

    Zolotarev, Andrey A.; Zhitova, Elena S.; Gabdrakhmanova, Faina A.; Krzhizhanovskaya, Maria G.; Zolotarev, Anatoly A.; Krivovichev, Sergey V.

    2017-02-01

    The crystal structure of batisite, Na2BaTi2 (Si4O12)O2, from the Inagli massif (Aldan, Yakutia, Russia) was refined to R 1 = 0.032 for 1449 unique observed reflections. The mineral is orthorhombic, Imma, a = 8.0921(5), b = 10.4751(7), c = 13.9054(9) Å, V = 1178.70(13) Å3. The mineral is based upon three-dimensional titanosilicate framework consisting of chains of corner-sharing MO6 octahedra (M = Ti, Nb, Fe and Zr) and vierer chains of corner-sharing SiO4 tetrahedra. Both chains are parallel to the a axis and are linked by sharing peripheral O atoms. The octahedral chains display disorder of M atoms and bridging O sites related to the out-of-center distortion of octahedral geometry around Ti4+ cations. Electron microprobe analysis gives SiO2 39.46, TiO2 24.66, BaO 21.64, Na2O 7.56, K2O 4.38, Fe2O3 0.90, ZrO2 0.66, Nb2O5 0.36, (H2O)calc 0.58, sum 99.76 wt%. The seven strongest X-ray powder-diffraction lines [listed as d in Å (I) hkl] are: 8.39 (94) 011, 3.386 (56) 031, 3.191 (36) 123, 2.910 (46) 222, 2.896 (100) 024, 2.175 (45) 035, 1.673 (57) 055. The thermal behaviour of batisite in the temperature range from 25 to 950 °C was studied using high-temperature powder X-ray diffraction. The thermal expansion coefficients along the principal crystallographic axes are: α a = 14.4 × 10-6, α b = 8.7 × 10-6, α c = 8.4 × 10-6, α V = 31.5 °C-1 for the temperature range 25-500 °C and α a = 19.6 × 10-6, α b = 9.1 × 10-6, α c = 8.8 × 10-6, α V = 37.6 °C-1 for the temperature range 500-900 °C. The direction of maximal thermal expansion is parallel to the chains of both MO6 octahedra and SiO4 tetrahedra, which can be explained by the stretching of silicate chains due to the increasing thermal vibrations of the Ba2+ cations. At 1000 °C, the titanosilicate framework in batisite collapses with the formation of fresnoite, Ba2TiSi2O7O.

  18. Effet Hall et Magnetisme des Alliages Amorphes Nickel-Zirconium Fabriques Par Pulverisation

    Science.gov (United States)

    Morel, Robert

    Cette these se situe dans le cadre d'une etude des proprietes electroniques et structurales des alliages metalliques amorphes, en cours depuis quelques annees a l'Universite de Montreal. Ce programme nous a entre autres amene a caracteriser la magnetoresistivite et l'effet Hall d'alliages FeZr, CoZr et NiZr, ce qui a permis de mettre en evidence deux caracteristiques de l'effet Hall: Dans les alliages amorphes ferromagnetiques, la resistivite elevee engendre un effet Hall extraordinaire beaucoup plus important que celui enregistre dans les metaux cristallins. La polarisation des spins entrai ne une asymetrie de la diffusion qui, tant dans les phases cristalline et amorphe, est tenue responsable de cette contribution. L'autre particularite du comportement de Hall de ces systemes est le renversement de signe du coefficient de Hall ordinaire, qui passe du negatif au positif dans les echantillons plus riches en zirconium. Dans les metaux cristallins, un modele d'electrons libres predit un signe negatif a moins que la conduction ne soit dominee par les trous. Or, dans un milieu desordonne les memes concepts sont difficilement applicables et de nouvelles theories ont du etre elaborees pour expliquer ce phenomene. Jusqu'a maintenant, l'etude des alliages amorphes nickel-zirconium s'est faite surtout a partir d'echantillons fabriques par trempe sur roue. Malheureusement cette technique ne permet pas la fabrication d'alliages contenant plus de 70% de nickel, a l'exception du seul compose Ni _{90}Zr_{10 }. Pour pallier a cette lacune et etendre nos connaissance a l'ensemble de la gamme de compositions, nous avons fabrique par pulverisation cathodique des echantillons NiZr amorphes--et quelques alliages cristallins tres riches en nickel--couvrant une bonne partie de la gamme interdite par la technique de trempe sur roue. Dans un premier temps, par comparaison avec les resultats connus nous avons mis en evidence les similitudes et les differences entre les alliages obtenus par

  19. Ion Microprobe U-Th Ages of Zircon From Plutonic Rock Fragments Ejected by Mount Veniaminof Volcano, Alaska Peninsula

    Science.gov (United States)

    Bacon, C. R.; Sisson, T. W.; Mazdab, F. K.

    2006-05-01

    Mount Veniaminof volcano in the Aleutian arc provides an unusual opportunity to directly relate volcanic rocks to a coeval shallow pluton. Fragments of medium- to coarse-grained plutonic rock were ejected during Veniaminof's 3700 14C yr B.P. caldera-forming eruption. The gabbro, diorite, and miarolitic granodiorite fragments are direct evidence of assembly of a shallow pluton consisting of cumulate mush and vapor- saturated residual melt segregations. We used the USGS-Stanford SHRIMP RG (Sensitive High-Resolution Ion MicroProbe with Reverse Geometry) to analyze ~30-μm-diameter areas a few μm deep on individual polished 40-150 μm zircons separated from these plutonic rocks. Samples were sputtered with a 16-22 nA primary beam of 16O- ions and secondary ion intensities were measured for 90Zr216O, 180Hf16O, 238U, 230Th16O, background, 232Th16O, and 238U16O. Crystallization ages for the single zircon populations in each rock were determined by fitting isochrons to SHRIMP RG data plotted on (230Th/232Th) versus (238U/232Th) activity ratio diagrams, after rejecting analyses affected by contamination from the epoxy mounting medium (combination of 232Th and epoxy constituents that overlaps 230Th16O). The SHRIMP RG analyses define 238U-230Th isochron ages of 17.5 ± 1.8 ka and 11.7 +4.7/-4.5 ka for zircon crystallization in granodiorite and diorite, respectively (±2σ). Sparse zircons from two gabbro samples give 238U-230Th model ages of 36.6 +7.1/-6.7 ka and 26.4 +6.7/-6.4 ka using initial activity ratios defined by the granodiorite and diorite isochrons. Zircons from granodiorite and diorite, commonly bearing ~0.2-5 μm fluid inclusions, have exceptionally high U and Th contents (up to 2 and 5 wt.%, respectively) that may be explained by crystallization in the presence of late-magmatic aqueous fluid during passive degassing in the shallow subsurface. Veniaminof erupted medium- K basaltic through dacitic magmas over the past ~250 kyr that define an arc tholeiitic trend

  20. Productive performance and milk protein fraction composition of dairy cows supplemented with sodium monensin Desempenho produtivo e composição da fração protéica do leite em vacas sob suplementação com monensina sódica

    Directory of Open Access Journals (Sweden)

    Jefferson Rodrigues Gandra

    2010-08-01

    Full Text Available The objective of this work was to evaluate the levels of sodium monensin on lactating cows and their effects on productive performance and milk protein fraction composition. It was used 12 Holstein cows, distributed in four balanced 3 × 3 Latin squares, and fed three diets: one control without monensin, and two diets with monensin at the levels of 24 or 48 mg/kg DM added to the concentrate. Milk production was daily measured throughout the entire experimental period. The samples used for analysis of milk composition were collected on two alternated days from the two daily milking. Non-protein nitrogen, total nitrogen and non-casein nitrogen contents were directly evaluated in the milk, and casein, whey protein and true protein contents were indirectly determined. The use of monensin in the rations reduced dry matter and nutrient intake, especially when diet with 48 mg/kg of dry matter was given. The ration with 24 mg/kg of DM increased milk production, with or without correction, and also fat and lactose yield, and it improved productive efficiency. The levels of monensin in the ratios did not influence contents of milk crude protein, non-protein nitrogen, non-casein nitrogen, true protein, casein, casein/true protein ratio, whey protein, and of all those fractions expressed as percentage of crude protein. The utilization of monensin in the ratio at the dose of 24 mg/kg of DM influences positively the productive performance of lactating cows, and it does not influence the composition of milk protein fractions.Objetivou-se avaliar níveis de monensina sódica para vacas em lactação e seus efeitos no desempenho produtivo e na composição da fração protéica do leite. Foram utilizadas 12 vacas da raça Holandesa, distribuídas em quatro quadrados latinos 3 × 3 balanceados e alimentadas com três rações: uma controle sem monensina, e duas com monensima nos níveis de 24 mg/kg de matéria seca ou 48 mg/kg MS adicionada ao concentrado. A

  1. Magnesium and 54Cr isotope compositions of carbonaceous chondrite chondrules – Insights into early disk processes

    Science.gov (United States)

    Olsen, Mia B.; Wielandt, Daniel; Schiller, Martin; Van Kooten, Elishevah M.M.E.; Bizzarro, Martin

    2016-01-01

    We report on the petrology, magnesium isotopes and mass-independent 54Cr/52Cr compositions (μ54Cr) of 42 chondrules from CV (Vigarano and NWA 3118) and CR (NWA 6043, NWA 801 and LAP 02342) chondrites. All sampled chondrules are classified as type IA or type IAB, have low 27Al/24Mg ratios (0.04–0.27) and display little or no evidence for secondary alteration processes. The CV and CR chondrules show variable 25Mg/24Mg and 26Mg/24Mg values corresponding to a range of mass-dependent fractionation of ~500 ppm (parts per million) per atomic mass unit. This mass-dependent Mg isotope fractionation is interpreted as reflecting Mg isotope heterogeneity of the chondrule precursors and not the result of secondary alteration or volatility-controlled processes during chondrule formation. The CV and CR chondrule populations studied here are characterized by systematic deficits in the mass-independent component of 26Mg (μ26Mg*) relative to the solar value defined by CI chondrites, which we interpret as reflecting formation from precursor material with a reduced initial abundance of 26Al compared to the canonical 26Al/27Al of ~5 × 10−5. Model initial 26Al/27Al values of CV and CR chondrules vary from (1.5 ± 4.0) × 10−6 to (2.2 ± 0.4) × 10−5. The CV chondrules display significant μ54Cr variability, defining a range of compositions that is comparable to that observed for inner Solar System primitive and differentiated meteorites. In contrast, CR chondrites are characterized by a narrower range of μ54Cr values restricted to compositions typically observed for bulk carbonaceous chondrites. Collectively, these observations suggest that the CV chondrules formed from precursors that originated in various regions of the protoplanetary disk and were then transported to the accretion region of the CV parent asteroid whereas CR chondrule predominantly formed from precursor with carbonaceous chondrite-like μ54Cr signatures. The observed μ54Cr variability in chondrules from

  2. Extracts of Azadirachta indica and Melia azedarach seeds inhibit folliculogenesis in albino rats

    Directory of Open Access Journals (Sweden)

    Roop J.K.

    2005-01-01

    Full Text Available The seed oil of Azadirachta indica A. Juss (neem is used in traditional medicine for its antidiabetic, spermicidal, antifertility, antibacterial, and wound healing properties. The present study was undertaken to investigate the quantitative aspects of follicular development in cyclic female albino rats (135 ± 10 g; 8 groups with 6 animals in each group after oral administration of polar (PF and non-polar (NPF fractions of A. indica seed extract at 3 and 6 mg kg body weight-1 day-1 and Melia azedarach Linn. (dharek seed extract at 24 mg kg body weight-1 day-1 for 18 days. The extracts were prepared using a flash evaporator at 35°C and then dissolved in olive oil to prepare doses on a per kg body weight basis. There was a significant reduction (P = 0.05 in the number of normal single layered follicles (A. indica: 0.67 ± 0.33 and 4.67 ± 2.03 after 3 and 6 mg/kg NPF, and 3.33 ± 1.67 and 1.00 ± 1.00 after 3 and 6 mg/kg PF vs control: 72.67 ± 9.14 and M. azedarach: 0.60 ± 0.40 and 1.80 ± 1.2 after 24 mg/kg PF and NPF, respectively, vs control: 73.40 ± 7.02 and follicles in various stages (I-VII of follicular development in all treatment groups. These extracts also significantly reduced (P = 0.05 the total number of normal follicles in the neem (14.67 ± 5.93 and 1.00 ± 1.00 after 3 and 6 mg/kg PF and 3.67 ± 0.88 and 5.33 ± 2.03 after 3 and 6 mg/kg NPF and dharek (13.00 ± 3.58 and 14.60 ± 2.25 after 24 mg/kg NPF and PF treatments compared to control (216.00 ± 15.72 and 222.20 ± 19.52, respectively. Currently, indiscriminate use of persistent and toxic rodenticides to control rodent populations has created serious problems such as resistance and environmental contamination. Therefore, it becomes necessary to use ecologically safe and biologically active botanical substances that are metabolized and are not passed on to the next trophic level, and that interfere with the reproductive potential particularly growth and differentiation of

  3. Mercury concentrations in water and mercury and selenium concentrations in fish from Brownlee Reservoir and selected sites in the Boise and Snake Rivers, Idaho and Oregon, 2013–15

    Science.gov (United States)

    Williams, Marshall L.; MacCoy, Dorene E.

    2016-06-30

    Mercury (Hg) analyses were conducted on samples of sport fish and water collected from selected sampling sites in Brownlee Reservoir and the Boise and Snake Rivers to meet National Pollution Discharge and Elimination System (NPDES) permit requirements for the City of Boise, Idaho, between 2013 and 2015. City of Boise personnel collected water samples from six sites between October and November 2013 and 2015, with one site sampled in 2014. Total Hg concentrations in unfiltered water samples ranged from 0.48 to 8.8 nanograms per liter (ng/L), with the highest value in Brownlee Reservoir in 2013. All Hg concentrations in water samples were less than the U.S. Environmental Protection Agency (USEPA) Hg chronic aquatic life criterion of 12 ng/L.The USEPA recommended a water-quality criterion of 0.30 milligrams per kilogram (mg/kg) methylmercury (MeHg) expressed as a fish-tissue residue value (wet-weight MeHg in fish tissue). The Idaho Department of Environmental Quality adopted the USEPA’s fish-tissue criterion and established a reasonable potential to exceed (RPTE) threshold 20 percent lower than the criterion or greater than 0.24 mg/kg Hg based on an average concentration of 10 fish from a receiving waterbody. NPDES permitted discharge to waters with fish having Hg concentrations exceeding 0.24 mg/kg are said to have a reasonable potential to exceed the water-quality criterion and thus are subject to additional permit obligations, such as requirements for increased monitoring and the development of a Hg minimization plan. The Idaho Fish Consumption Advisory Program (IFCAP) issues fish advisories to protect general and sensitive populations of fish consumers and has developed an action level of 0.22 mg/kg Hg in fish tissue. Fish consumption advisories are water body- and species-specific and are used to advise allowable fish consumption from specific water bodies. The geometric mean Hg concentration of 10 fish of a single species collected from a single water body

  4. Mercury concentrations in water, and mercury and selenium concentrations in fish from Brownlee Reservoir and selected sites in Boise and Snake Rivers, Idaho and Oregon, 2013

    Science.gov (United States)

    MacCoy, Dorene E.

    2014-01-01

    Mercury (Hg) analyses were conducted on samples of sport fish and water collected from six sampling sites in the Boise and Snake Rivers, and Brownlee Reservoir to meet National Pollution Discharge and Elimination System (NPDES) permit requirements for the City of Boise, Idaho. A water sample was collected from each site during October and November 2013 by the City of Boise personnel and was analyzed by the Boise City Public Works Water Quality Laboratory. Total Hg concentrations in unfiltered water samples ranged from 0.73 to 1.21 nanograms per liter (ng/L) at five river sites; total Hg concentration was highest (8.78 ng/L) in a water sample from Brownlee Reservoir. All Hg concentrations in water samples were less than the EPA Hg chronic aquatic life criterion in Idaho (12 ng/L). The EPA recommended a water-quality criterion of 0.30 milligrams per kilogram (mg/kg) methylmercury (MeHg) expressed as a fish-tissue residue value (wet-weight MeHg in fish tissue). MeHg residue in fish tissue is considered to be equivalent to total Hg in fish muscle tissue and is referred to as Hg in this report. The Idaho Department of Environmental Quality adopted the EPA’s fish-tissue criterion and a reasonable potential to exceed (RPTE) threshold 20 percent lower than the criterion or greater than 0.24 mg/kg based on an average concentration of 10 fish from a receiving waterbody. NPDES permitted discharge to waters with fish having Hg concentrations exceeding 0.24 mg/kg are said to have a reasonable potential to exceed the water-quality criterion and thus are subject to additional permit obligations, such as requirements for increased monitoring and the development of a Hg minimization plan. The Idaho Fish Consumption Advisory Program (IFCAP) issues fish advisories to protect general and sensitive populations of fish consumers and has developed an action level of 0.22 mg/kg wet weight Hg in fish tissue. Fish consumption advisories are water body- and species-specific and are used to

  5. Magnesium and 54Cr isotope compositions of carbonaceous chondrite chondrules - Insights into early disk processes

    Science.gov (United States)

    Olsen, Mia B.; Wielandt, Daniel; Schiller, Martin; Van Kooten, Elishevah M. M. E.; Bizzarro, Martin

    2016-10-01

    We report on the petrology, magnesium isotopes and mass-independent 54Cr/52Cr compositions (μ54Cr) of 42 chondrules from CV (Vigarano and NWA 3118) and CR (NWA 6043, NWA 801 and LAP 02342) chondrites. All sampled chondrules are classified as type IA or type IAB, have low 27Al/24Mg ratios (0.04-0.27) and display little or no evidence for secondary alteration processes. The CV and CR chondrules show variable 25Mg/24Mg and 26Mg/24Mg values corresponding to a range of mass-dependent fractionation of ∼500 ppm (parts per million) per atomic mass unit. This mass-dependent Mg isotope fractionation is interpreted as reflecting Mg isotope heterogeneity of the chondrule precursors and not the result of secondary alteration or volatility-controlled processes during chondrule formation. The CV and CR chondrule populations studied here are characterized by systematic deficits in the mass-independent component of 26Mg (μ26Mg∗) relative to the solar value defined by CI chondrites, which we interpret as reflecting formation from precursor material with a reduced initial abundance of 26Al compared to the canonical 26Al/27Al of ∼5 × 10-5. Model initial 26Al/27Al values of CV and CR chondrules vary from (1.5 ± 4.0) × 10-6 to (2.2 ± 0.4) × 10-5. The CV chondrules display significant μ54Cr variability, defining a range of compositions that is comparable to that observed for inner Solar System primitive and differentiated meteorites. In contrast, CR chondrites are characterized by a narrower range of μ54Cr values restricted to compositions typically observed for bulk carbonaceous chondrites. Collectively, these observations suggest that the CV chondrules formed from precursors that originated in various regions of the protoplanetary disk and were then transported to the accretion region of the CV parent asteroid whereas CR chondrule predominantly formed from precursor with carbonaceous chondrite-like μ54Cr signatures. The observed μ54Cr variability in chondrules from CV

  6. STUDY ON ADSORPTION MECHANISM OF GALLIC ACID BY Aspergillus oryzae MYCELIA%米曲霉菌体吸附没食子酸的机制研究

    Institute of Scientific and Technical Information of China (English)

    庞巧霞; 张志才; 李敏

    2014-01-01

    In order to solve the problem of gallic acid-contaminated wastewater,bioactive mycelia of Aspergillus oryzae (A.oryzae) CGMCC5992 was used as a kind of bio-adsorbent.Effects of pH,mycelium content,treatment time and initial concentration of gallic acid on removal efficiency of gallic acid were studied.The adsorption mechanism was investigated by kinetic and isotherm model simulation and scanning electron microscopy (SEM).The results showed that the removal efficiency was 93.41% under the optimal conditions,such as initial pH value of 3,mycelium content of 8g/L,initial concentration of gallic acid of 100mg/L and treatment time of 6h.The biosorption equilibrium of gallic acid with mycelia could be described by Langmuir model and the maximum removal capacity was 20.24mg/g.The bisorption process of mycelia followed the Pseudo-second-order kinetics equation.SEM images indicated that the morphology and surface structure of mycelium changed after adsorption ofAspergillus oryzae (A.oryzae) CGMCC5992.%用米曲霉CGMCC5992活菌体作为生物吸附剂,吸附含没食子酸的废水.研究了菌体量、初始pH值、时间、起始浓度对吸附效果的影响.通过吸附动力学、热力学模型拟合,并结合扫描电镜(SEM)分析,初步探讨其吸附机理.结果表明,在菌体量8g/L,初始pH=3,起始浓度100mg/L,吸附6h条件下,去除率达到93.40%.米曲霉对没食子酸的吸附符合Langmuir模型,其最大吸附量可达20.24mg/g.吸附动力学可用准二级动力学方程描述.SEM显示,吸附后,米曲霉菌丝球形态以及菌体表面结构发生了改变.

  7. Randomized controlled trial for intermittent versus continuous propofol sedation for pediatric brain and spine magnetic resonance imaging studies.

    Science.gov (United States)

    Hassan, Nabil E; Betz, Bradford W; Cole, Morgan R; Wincek, Jeni; Reischman, Diann; Sanfilippo, Dominic J; Winterhalter-Rzeszutko, Kim M; Kopec, John S

    2011-11-01

    Intermittent bolus propofol is an effective agent for pediatric magnetic resonance imaging sedation but requires constant vigilance and dose titration. Magnetic resonance imaging-compatible infusion pumps may make it possible to continuously infuse propofol, achieving a steady level of sedation at a lower total dose. This study investigates total propofol dose, recovery time, and magnetic resonance image quality in children receiving intermittent vs. continuously infused propofol sedation in children undergoing brain and spine magnetic resonance imaging studies. An open-label, prospective, randomized, controlled study. A single-blinded radiologist rated the quality of magnetic resonance images. Children's hospital pediatric radiology sedation center. One hundred seventy children age 1 month to 18 yrs undergoing deep sedation for brain, spine, or both brain and spine magnetic resonance imaging. After informed consent, patients were randomly assigned to two groups: group 1 (intermittent) received a propofol bolus of 2-4 mg/kg, followed by repeat boluses of 0.5-2 mg/kg/dose as needed. Group C (continuous) received a bolus of propofol 2-4 mg/kg, followed by a continuous infusion of 100 μg/kg/min with 1-mg/kg/dose boluses with drip titration to effect. Patient demographics, sedation risk assessment, propofol dose, sedation recovery times, incidence of complications, and quality of the magnetic resonance imaging studies were measured. A total of 170 children were enrolled in the study, with 75 in group C and 95 in group I. Both groups were similar with regard to age, weight, gender, and magnetic resonance imaging study type. Group C required a lesser dose of propofol (132 ± 54 μg/kg/min) compared to (162 ± 74 μg/kg/min) in that required in group I (p = .018). There were no differences between the two groups with regard to quality of the imaging study, recovery time, or incidence of complications. Compared to intermittent bolus dosing, continuous propofol infusion provides lesser dose exposure without impacting recovery time or quality of the magnetic resonance imaging study.

  8. Non-immunogenicity of overlapping gag peptides pulsed on autologous cells after vaccination of HIV infected individuals.

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    Henrik N Kløverpris

    Full Text Available BACKGROUND: HIV Gag-specific CD4+ and CD8+ T-cell responses are important for HIV immune control. Pulsing overlapping Gag peptides on autologous lymphocytes (OPAL has proven immunogenic and effective in reducing viral loads in multiple pigtail macaque studies, warranting clinical evaluation. METHODOLOGY: We performed a phase I, single centre, placebo-controlled, double-blinded and dose-escalating study to evaluate the safety and preliminary immunogenicity of a novel therapeutic vaccine approach 'OPAL-HIV-Gag(c'. This vaccine is comprised of 120 15mer peptides, overlapping by 11 amino acids, spanning the HIV Gag C clade sequence proteome, pulsed on white blood cells enriched from whole blood using a closed system, followed by intravenous reinfusion. Patients with undetectable HIV viral loads (<50 copies/ml plasma on HAART received four administrations at week 0, 4, 8 and 12, and were followed up for 12 weeks post-treatment. Twenty-three people were enrolled in four groups: 12 mg (n = 6, 24 mg (n = 7, 48 mg (n = 2 or matching placebo (n = 8 with 18 immunologically evaluable. T-cell immunogenicity was assessed by IFNγ ELIspot and intracellular cytokine staining (ICS. RESULTS: The OPAL-HIV-Gag(c peptides were antigenic in vitro in 17/17 subjects. After vaccination with OPAL-HIV-Gag(c, 1/6 subjects at 12 mg and 1/6 subjects at 24 mg dose groups had a 2- and 3-fold increase in ELIspot magnitudes from baseline, respectively, of Gag-specific CD8+ T-cells at week 14, compared to 0/6 subjects in the placebo group. No Gag-specific CD4+ T-cell responses or overall change in Rev, Nef, Tat and CMV specific responses were detected. Marked, transient and self-limiting lymphopenia was observed immediately post-vaccination (4 hours in OPAL-HIV-Gag(c but not in placebo recipients, with median fall from 1.72 to 0.67 million lymphocytes/mL for active groups (P<0.001, compared to post-placebo from 1.70 to 1.56 lymphocytes/ml (P = 0.16. CONCLUSION

  9. 文冠果油理化特性及组成分析研究%STUDY ON PHYSICOCHEMICAL PROPERTIES AND COMPOSITION OF XANTHOCERAS SORBIFOLIA BUNGE OIL

    Institute of Scientific and Technical Information of China (English)

    赵芳; 李桂华; 刘振涛; 靳晓鹏

    2011-01-01

    采用气相色谱、胰脂酶水解法分析了文冠果油脂肪酸组成和Sn-2位脂肪酸分布,油脂脂肪酸组成中不饱和脂肪酸含量接近90%,油酸、亚油酸含量75.5%以上;Sn-2位脂肪酸中不饱和脂肪酸为97%,其中油酸、亚油酸含量较高(95.0%).高效液相色谱、Rancimat仪测定结果表明:文冠果油中维生素E含量为51.24mg/100g;氧化稳定性值在110℃时为4.24 h;碘值为111.9g/100g,为半干性油脂;文冠果仁中粗脂肪含量达62%、粗蛋白为29%以上,是一种珍贵的木本油料.%The article analyzed the composition and Sn-2 position fatty acid distribution of Xanthoce sorbifolia Bunge oil by using gas chromatography and pancreas lipase hydrolysis. The fatty acids contained unsaturated fatty acid up to 90%, in which oleic acid and linoleic acid were more than 75.5%; the Sn-2 position fatty acids contained unsaturated fatty acid 97%, in which oleic acid and linoleic acid were 95%. Through HPLC and Rancimat determination, the results showed that the Xanthoce sorbifolia Bunge oil contained vitamin E 51.24 mg/lOOg; the duration of the oxidation stability at 110 °C was 4.24 hours; the iodine value was 111.9 g/lOOg; and the Xanthoce sorbifolia Bunge oil was semi-drying oil. The Xanthoce sorbifolia Bunge seed contained crude fat 62% and crude protein above 29%, and is a previous woody oil plant.

  10. Validação de modelos de predição de nitrogênio uréico no leite, estimando-se o consumo individual pelo consumo do rebanho - DOI: 10.4025/actascianimsci.v28i1.666 Validation of models to predict milk urea nitrogen concentrations, using herd intake to estimate individual dry matter intake - DOI: 10.4025/actascianimsci.v28i1.666

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    Karyne Oliveira Coelho

    2006-01-01

    Full Text Available O objetivo deste trabalho foi validar modelos de predição de nitrogênio uréico no leite (NUL, visando contribuir para avaliação nutricional de dietas de vacas. Foram utilizadas 8.833 observações de vacas holandesas de um rebanho comercial. A produção de leite, o peso vivo, o número de dias em lactação e o número de lactações foram coletados no dia da amostragem do leite. Amostras de leite foram coletadas mensalmente para determinação da sua composição. Para a avaliação dos 3 modelos, foram medidas acurácia, precisão e robustez. O modelo 3, apesar de mais acurado (viés=-0,21 mg/dL, foi menos preciso (erro residual=5,24 mg/dL que o modelo 2 (viés=-1,72 e erro residual=4,90 mg/dL, enquanto o modelo 1 foi o menos acurado (viés=2,93 mg/dL e o menos preciso (erro residual=5,99 mg/dL. Houve falta de robustez para os 3 modelos. Os três modelos de predição de NUL diferiram entre si quanto à acurácia, precisão e robustez.The objective of this study was to validate prediction models for milk urea nitrogen (MUN, aiming at evaluating utilization efficiency of diets for dairy cows. Data (8,833 observations from Holstein cows were used. Milk production, body weight, days in milk and lactation number were collected on the milk sampling days. Milk samples were collected monthly for composition analysis. In order to evaluate the three models, accuracy, precision and robustness were tested. Despite being more accurate (mean bias=-0.21 mg/dL, model 3 was less precise (residual error=5.24 mg/dL than model 2 (mean bias=-1.72 and residual error=4.90 mg/dL, while model 1 was the least accurate (mean bias=2.93 mg/dL and the least precise (residual error=5.99 mg/dL. There was lack of robustness for the three models. Models for predicting MUN differ among themselves with regard to accuracy, precision and robustness.

  11. Study on the degradation of diethyl phthalate by UV/Fe0 system%UV/Fe0体系降解邻苯二甲酸二乙酯的研究

    Institute of Scientific and Technical Information of China (English)

    胡菲菲; 邵庆国

    2013-01-01

    尝试利用UV/Fe0体系降解邻苯二甲酸二乙酯(DEP)废水,探讨了pH、Fe0投加量、DEP初始浓度等影响因素对降解效果的影响.结果表明,对于24 mg/L的DEP废水,在pH=3、Fe0投加量为20mg/L时,反应60 min后的DEP降解率可达93.5%,并且该降解过程符合准一级反应动力学规律;在UV/Fe0体系降解DEP过程中,Fe2+、Fe3+浓度均在反应一定时间后趋于平衡,并且Fe2+的浓度始终高于Fe3+;UV、Fe0在DEP的降解中存在协同作用.UV/Fe0体系对DEP废水具有良好的降解效果,并且不需要额外添加高价的H2O2,为DEP废水的工业化处理提供了一种较好的方法.%UV/Fe° system was applied for the treatment of diethyl phthalate (DEP) containing wastewater. The effect of pH,Fe° dosage, and initial DEP concentration on DEP degradation efficiency was investigated. The results showed that when the initial DEP was 24 mg/L,Fe° dosage was 20 mg/L and pH was 3,the degradation rate of DEP could reach to 93. 5 % after 60 min of reaction,and the degradation process could be better fitted by pseudo first-order kinetics. During the degradation process,the concentration of Fe2+ , Fe3+ in UV/Fe° system reached equilibrium after a certain time of reaction,and Fe2+ was consistently higher than Fe3+. There was synergistic effect found between UV and Fe° in the DEP degradation process. UV/Fe° system exhibited perfect DEP degradation efficiency without adding high-priced H2O2 ,so it was a suitable method for the industrialized treatment of DEP containing wastewater.

  12. 自拟调脉汤联合西药治疗老年病态窦房结综合征疗效观察%Obsevation on clinical effect of self-made Tiaomai decoction combined with western medicine in treating senile sick sinus syndrome

    Institute of Scientific and Technical Information of China (English)

    蒋永平

    2013-01-01

    Objective To observe the clinical effects of self - made Tiaomai decoction combined with western medicine in treatment of senile sick sinus syndrome ( SSS ) . Methods One hundred patients with SSS were randomly divided into western medicine ( WM ) control group ( n = 50 ) and traditional and western medicine ( TWM ) treatment group ( n = 50 ). Patients in control group accepted oral administration of aniso-damine 10 mg and salbutamol 2.4 mg, 3 times daily. Patients in TWM treatment group were additionally given with Tiaomai Tang ( decoction ), one dose per day, and the therapeutic course of both groups was 15 days. The curative effects were observed after 2 courses of treatment. Results After treatment, the total effective rate of TWM treatment group was 88% , it was obviously higher than that ( 60% ) of control group ( P 〈0. 01 ) . Heart rate and ECG had been improved in patients of these two groups, but their difference was remarkable ( P 〈0. 01 ). Conclusion The application of self - made Tiaomiao decoction combined with western medicine in treatment of senile sick sinus syndrome has remarkable effects and good safety.%目的 观察自拟调脉汤联用西药治疗老年病态窦房结综合征的临床疗效.方法 将100例老年病态窦房结综合征患者随机分为对照组50例和治疗组50例,对照组在原发病治疗基础上口服山莨菪碱10 mg、沙丁胺醇2.4 mg,每日3次;治疗组在对照组基础上加服自拟调脉汤,每日1剂,1疗程为15日,2个疗程后判定疗效.结果 总有效率治疗组为88.0%,对照组为60.0%.治疗组总有效率明显高于对照组(P<0.01).两组患者治疗后心率、心电图指标均有改善,但治疗组改善疗效均明显优于对照组(P<0.01).结论 自拟调脉汤联用西药治疗老年病态窦房结综合征疗效显著,安全性好.

  13. Oregano essential oil-pectin edible films as anti-quorum sensing and food antimicrobial agents

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    Victoria eAlvarez

    2014-12-01

    Full Text Available Edible films can be used as carriers for antimicrobial compounds to assure food safety and quality; in addition, pathogenesis of food bacteria is related to a cell to cell communication mechanism called quorum sensing (QS. Oregano essential oil (OEO has proved to be useful as food antimicrobial; however, its food applications can be compromised by the volatile character of its active constituents. Therefore, formulation of edible films containing OEO can be an alternative to improve its food usages. QS inhibitory activity of OEO and pectin-OEO films was evaluated using Chromobacterium violaceum as bacterial model. Additionally, antibacterial activity was tested against Escherichia coli O157:H7, Salmonella Choleraesuis, Staphylococcus aureus, and Listeria monocytogenes. OEO was effective to inhibit bacterial growth at MIC of 0.24 mg/mL for all tested bacteria and MBC of 0.24, 0.24, 0.48, and 0.24 mg/mL against E. coli O157:H7, S. Choleraesuis, S. aureus, and L. monocytogenes, respectively. Pectin-films incorporated with 36.1 and 25.9 mg/mL of OEO showed inhibition diameters of 16.3 and 15.2 mm for E. coli O157:H7; 18.1 and 24.2 mm for S. Choleraesuis; 20.8 and 20.3 mm for S. aureus; 21.3 and 19.3 mm for L. monocytogenes, respectively. Pectin-OEO film (15.7 mg/mL was effective against E. coli O157:H7 (9.3 mm, S. aureus (9.7 mm, and L. monocytogenes (9.2 mm, but not for S. Choleraesuis. All concentrations of OEO (0.0156, 0.0312, 0.0625 and 0.125 mg/mL and pectin-OEO films (15.7, 25.9 and 36.1 mg/mL showed a significant anti-QS activity expressed as inhibition of violacein production by C. violaceum. Additionally, the application of pectin-OEO films was effective reducing total coliforms, yeast, and molds of shrimp and cucumber slices stored at 4 °C during 15 d. These results demonstrated the potential of pectin films enriched with OEO as food related microorganisms and QS inhibitors.

  14. A randomised, placebo-controlled, first-in-human study of a novel clade C therapeutic peptide vaccine administered ex vivo to autologous white blood cells in HIV infected individuals.

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    Akil Jackson

    Full Text Available BACKGROUND: Preclinical studies of overlapping 15mer peptides, spanning SIV, SHIV or HIV, pulsed on autologous PBMC ex vivo have demonstrated high level, virus-specific T cell responses and viral suppression in non-human primates (NHP. Opal-HIV-Gag(c consists of 120 synthetic 15mer peptides spanning Clade C, consensus Gag, manufactured to current good manufacturing practice; having been evaluated in a good laboratory practice toxicology study in Macaca mulatta. We evaluated the safety and preliminary immunogenicity of such peptides administered intravenously after short-duration ex vivo incubation, to HIV-positive adults on suppressive antiretroviral therapy. METHODS AND FINDINGS: A first-in-human, placebo-controlled, double-blind, dose escalation study was conducted. Twenty-three patients with virus suppressed by antiretroviral therapy were enrolled in four groups 12 mg (n = 6, 24 mg (n = 6, 48 mg (n = 2 or matching placebo (n = 8. Treatment was administered intravenously after bedside enrichment of 120 mL whole blood for white cells using a closed system (Sepax S-100 device, with ex vivo peptide admixture (or diluent alone and 37°C incubation for one hour prior to reinfusion. Patients received 4 administrations at monthly intervals followed by a 12-week observation post-treatment. Opal-HIV-Gag(c was reasonably tolerated at doses of 12 and 24 mg. There was an increased incidence of temporally associated pyrexia, chills, and transient/self-limiting lymphopenia in Opal-HIV-Gag(c recipients compared to placebo. The study was terminated early, after two patients were recruited to the 48 mg cohort; a serious adverse event of hypotension, tachycardia secondary to diarrhoea occurred following a single product administration. An infectious cause for the event could not be identified, leaving the possibility of immunologically mediated product reaction. CONCLUSIONS: A serious, potentially life-threatening event of hypotension led to

  15. Standardized production of Phyllanthus tenellus Roxb. by plant tissue culture Produção padronizada de Phyllanthus tenellus Roxb. por cultura de tecidos vegetais

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    Cristiane Pimentel Victório

    2010-06-01

    Full Text Available Exigencies as ethic plant raw material are part of the needs of modern phytotherapy. Micropropagation offers opportunities to obtain mass propagation of superior genotypes in short time. This study aimed to develop a protocol of direct and indirect organogenesis of Phyllanthus tenellus Roxb. Nodal segments from plantlets obtained by in vitro germination were subcultured in modified Murashige and Skoog medium added with different plant growth regulators: IAA (indole-3-acetic acid, IBA (indole-3-butyric acid, GA3 (3-giberelic acid and KIN (kinetin. The highest proliferation rate was obtained using the combinations: IBA, KIN + GA3 (3.5 mg L-1 and IBA + KIN (2.4 mg L-1. Rooting was intensified after 40 days, reaching 100% for all media with indole-3-butyric acid. Addition of 2,4 dichlorophenoxyacetic acid (2,4D provided the best results for production of friable calli. Acclimatization was 100% effective for plantlets cultured in control medium, with decrease in survival rate in grown plantlets from media added with growth regulators.Exigências como matérias-primas vegetais fidedignas fazem parte das necessidades da fitoterapia moderna. A propagação in vitro permite a obtenção em massa de genótipos superiores, em curto espaço de tempo. Este estudo teve como objetivo desenvolver um protocolo de organogênese direta e indireta de Phyllanthus tenellus Roxb. Segmentos nodais de plântulas obtidas por germinação in vitro foram introduzidos em meio Murashige e Skoog adicionado de diferentes reguladores de crescimento vegetal: AIA (ácido indol-3-acético, AIB (ácido indol-3-butírico, AG3 (ácido giberélico-3 e CIN (cinetina. A maior taxa de proliferação foi obtida utilizando as combinações: AIB, CIN + AG3 (3,5 mg L-1 e AIB + CIN (2,4 mg L-1. A rizogênese foi intensificada após 40 dias de cultivo, atingindo 100% para todos os meios contendo AIB. A adição de ácido 2,4 diclorofenoxiacético (2,4D proporcionou os melhores resultados para produção de calos friáveis. A aclimatização foi 100% eficaz para as plantas cultivadas em meio controle, com a diminuição da taxa de sobrevivência para as plantas cultivadas em meios adicionados de reguladores de crescimento.

  16. Estudio farmacocinético de propofol en equinos Pharmacokinetic study of propofol in horses

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    C LÜDERS

    1998-01-01

    Full Text Available Se estudian las características farmacocinéticas de propofol en 6 caballos. Se determinaron parámetros farmacocinéticos de propofol cuantificando sus concentraciones sanguíneas en función del tiempo por HPLC, tras su administración de 2.4 mg/kg por vía endovenosa al grupo de animales. Los datos de concentración se interpretaron por un modelo abierto de 2 compartimentos, obteniéndose, entre otros, los valores de t1/2alfa, t1/2beta,Vd c, Vd ss, Vdbeta, Cl total y MRT. Las variables farmacodinámicas se encuentran acordes a la disposición cinética de este fármaco. El análisisde los parámetros farmacocinéticos del propofol indica que éste posee una rápida y pronta distribución a los tejidos y una rápida eliminación del organismo. El propofol se presenta como una alternativa anestésica factible de ser incorporada dentro de un protocolo anestésico en caballos. Los parámetros farmacocinéticos obtenidos contribuyen para una correcta dosificación ya sea para mantener un estado de anestesia por infusión continua o por inyecciones repetidasPharmacokinetic variables of propofol were studied in 6 horses. Blood concentration of propofol at different times, after a single dose of 2.4mg/kg bw, was determined by HPLC. An open two compartment model was used to evaluate blood concentrations of propofol. Values of t1/2alpha,t1/2beta, Vd c, Vd ss,Vdbeta, Cl total y MRT were obtained.The pharmacodynamic values show a narrow relationship with the pharmacokinetic disposition of this drug. Propofol’s pharmacokinetic disposition presented a rapid distribution and removal from organic tissues. It is concluded that propofol is an alternative to be considered in anaesthetic protocolsin horses, and the pharmacokinetic variables presented contribute to determinethe appropriate dose to be given

  17. Measurement of pulmonary flow reserve and pulmonary index of microcirculatory resistance for detection of pulmonary microvascular obstruction.

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    Rahn Ilsar

    Full Text Available BACKGROUND: The pulmonary microcirculation is the chief regulatory site for resistance in the pulmonary circuit. Despite pulmonary microvascular dysfunction being implicated in the pathogenesis of several pulmonary vascular conditions, there are currently no techniques for the specific assessment of pulmonary microvascular integrity in humans. Peak hyperemic flow assessment using thermodilution-derived mean transit-time (T(mn facilitate accurate coronary microcirculatory evaluation, but remain unvalidated in the lung circulation. Using a high primate model, we aimed to explore the use of T(mn as a surrogate of pulmonary blood flow for the purpose of measuring the novel indices Pulmonary Flow Reserve [PFR = (maximum hyperemic/(basal flow] and Pulmonary Index of Microcirculatory Resistance [PIMR = (maximum hyperemic distal pulmonary artery pressurex(maximum hyperemic T(mn]. Ultimately, we aimed to investigate the effect of progressive pulmonary microvascular obstruction on PFR and PIMR. METHODS AND RESULTS: Temperature- and pressure-sensor guidewires (TPSG were placed in segmental pulmonary arteries (SPA of 13 baboons and intravascular temperature measured. T(mn and hemodynamics were recorded at rest and following intra-SPA administration of the vasodilator agents adenosine (10-400 microg/kg/min and papaverine (3-24 mg. Temperature did not vary with intra-SPA sensor position (0.010+/-0.009 v 0.010+/-0.009 degrees C; distal v proximal; p = 0.1, supporting T(mn use in lung for the purpose of hemodynamic indices derivation. Adenosine (to 200 microg/kg/min & papaverine (to 24 mg induced dose-dependent flow augmentations (40+/-7% & 35+/-13% T(mn reductions v baseline, respectively; p<0.0001. PFR and PIMR were then calculated before and after progressive administration of ceramic microspheres into the SPA. Cumulative microsphere doses progressively reduced PFR (1.41+/-0.06, 1.26+/-0.19, 1.17+/-0.07 & 1.01+/-0.03; for 0, 10(4, 10(5 & 10(6 microspheres; p

  18. Potensi Ekowisata Danau di Kawasan Kamipang Kalimantan Tengah

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    Decenly -

    2014-09-01

    Full Text Available Penelitian ini bertujuan mengakaji potensi ekowisata di Kawasan Kamipang. Penelitian dilakukan melalui beberapa tahapan yaitu pra survei, survei dan analisis laboratorium. Pra survei dilakukan untuk menentukan 3 (tiga stasiun pengukuran kualitas air dan 3 (tiga posisi transek untuk analisis vegetasi. Survei meliputi pengukuran kualitas air danau, inventarisasi keanekaragaman ikan, analisis vegetasi, serta presepsi masyarakat lokal, pengunjung dan stakeholder. Analisis laboratorium yang meliputi identifikasi ikan dan tumbuhan. Potensi aspek abiotik dan sosial akan diuraikan secara deskriptif dan potensi aspek biologi dianalisis dengan pendekatan Indeks keanekaragaman ikan dan Indeks Nilai Penting (INP untuk vegetasi. Berdasarkan hasil penelitian, diketahui bahwa potensi abiotik yaitu berupa danau-danau alami dengan kondisi hidrologi yang cukup baik (nilai BOD berkisar antara 2-4 mg/L dengan kekeruhan kurang dari 25 NTU dan iklim tropis dengan tanah yang subur, sedangkan potensi biologi yaitu berupa keanekaragaman ikan dan tumbuh-tumbuhan di sekitar danau ditambah dengan keberadaan ikan dan tumbuhan yang termasuk dalam The IUCN Red List of Threatened Species 2013 dengan kategori Least Concern yaitu Ikan Peang (Channa maurilius, Balida (Notopterus chitala dan Tumbuhan Kantong Semar (Nepenthes gracilis. Adapun potensi sosial berupa keunikan budaya dan kesenian tradisional. The study was aimed to evaluate the potential of ecotourism in Kamipang Region. The study was conducted through several stages of pre-survey, survey, and laboratory analysis. The pre-survey was conducted to determine three (3 water quality monitoring stations and three (3 transect positions for vegetation analysis. The survey included the measurement of lake water quality, the inventory of fish biodiversity, the vegetation analysis, and the perception of the local community, visitors and stakeholders. Laboratory analysis included the identification of fishes and plants. The potential of abiotic and social aspects were outlined descriptively and the potential biological aspects were analyzed using fish biodiversity index and vegetation important value index. The study showed the potential of abiotic aspects i.e. natural lakes with relatively good hydrological conditions (BOD value ranged between 2-4 mg/L and turbidity was less than 25 NTU and tropical climate with fertile soil, whereas the biological potential comprised the diversity of fishes and vegetation around the lake along with the presence of fishes and plants that have been listed in the IUCN Red List of Threatened Species 2013 from the category of Least Concerned, i.e. Peang fish (Channa Maurilius, Balida (Notopterus Chitala and Kantong Semar (pitcher plants (Nepenthes Gracilis. The social potential was the uniqueness culture and the traditional arts.

  19. Study on the quarantine fumigation technology of Phytophthora sojae%大豆疫霉检疫熏蒸处理技术初探

    Institute of Scientific and Technical Information of China (English)

    李丽; 刘涛; 张凡华; 任放; 王跃进

    2013-01-01

    Soybean Phytophthora root rot (PPR) that cause by Phytophthora sojae is one of the most serious diseases in the main soybean production area all over the world. In this manuscript, we analyzed the fungitoxicity of methyl bromide, propylene oxide, methyl iodide and carbonyl sulfide, their influences on the quality of soybean were also determined. Our results confirmed the efficacy of the four fumigants against Phytophthora sojae, their EC99 values were methyl bromide 21.24mg/L, propylene oxide 33.21 mg/L, methyl iodide 4.64 mg/L and carbonyl sulfide 46. 73mg/L for 24h fumigation at 20℃. Moreover, quality analysis results showed that there were not significant differences between untreated and treated soybeans after 30d storage, indicating that fumigation with tested fumigants would be the candidates for control of Phytophthora sojae, especially methyl iodide.%大豆疫霉根腐病(Soybean Phytophthora root rot,简称PPR)由大豆疫霉(Phytophthora sojae Kaufmann&Gerdemann)引发,在世界大豆主产区广泛发生,危害严重.为有效防控大豆疫霉根腐病跨境传播,本文测定了溴甲烷、环氧丙烷、碘甲烷和氧硫化碳4种熏蒸剂对大豆疫霉的毒力及其致死剂量对大豆品质的影响.结果表明,20℃下,4种熏蒸剂均有一定杀菌效果,熏蒸24h的EC99分别为:溴甲烷21.24mg/L、环氧丙烷33.21 mg/L、碘甲烷4.64 mg/L、氧硫化碳46.73 mg/L.大豆品质测定结果表明,致死剂量的4种熏蒸剂熏蒸后,大豆粗脂肪、粗蛋白等等主要品质指标无显著变化.本研究为进境大豆携带大豆疫霉的检疫处理提供了候选技术,碘甲烷在带菌大豆检疫处理中的应用前景值得关注.

  20. Antioxidant and Antibacterial Activity of Essential Oil from Sichuan Bergamot%川佛手精油抗氧化及抑菌活性的研究

    Institute of Scientific and Technical Information of China (English)

    韩林; 夏兵; 丁博; 申连长; 周倩倩; 徐佳雨

    2014-01-01

    为了研究川佛手精油的抗氧化和抑菌活性,以石油醚作为溶剂超声辅助提取得到川佛手精油,测定其抗氧化活性和体外抑菌活性,川佛手精油对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌、苏云金芽孢杆菌、肠球菌5种常见食源性污染菌的抑菌效果。结果表明:川佛手精油含有丰富的多酚和黄酮类物质,具有一定的抗氧化活性,对DPPH 和ABTS自由基清除能力较强,EC50分别为3.92,1.88 mg/mL。体外抑菌试验表明川佛手精油对肠球菌有很好的抑菌效果,最低抑菌浓度(MIC)为24 mg/mL,抑菌强弱顺序为:肠球菌、苏云金芽孢杆菌、枯草芽孢杆菌、金黄色葡萄球菌、大肠杆菌。%In order to study the antioxidant and antibacterial activity of essential oil from Sichuan bergamot,petroleum ether is used as the solvent to get the extract by ultrasonication-assisted extraction, DPPH radical scavenging assay, ABTS radical scavenging assay and potassium ferricyanide reduction are used to measure the antioxidant activity.Five common food-borne polluted bacteria such as Escherichia coli,Bacillus subtillis,Staphylococcus aureus,Bacillus thuringiensis and Enterococcus are employed to test the antibacterial activity in vitro.The result indicates that the essential oil from Sichuan bergamot has amount of total phenolics and total flavonoids and shows good antioxidant activity,as well as scavenging the DPPH and ABTS radicals,EC50 is 3.92,1.88 mg/mL respectively.The in vitro antibacterial experiments show the essential oil has better antibacterial efficiency to Bacillus thuringiensis than others,the minimum inhibitory concentration (MIC)is both 24 mg/mL,the sequence of antibacterial activity is Enterococcus> Bacillus thuringiensis>Bacillus subtillis> Staphylococcus aureus>Escherichia coli.

  1. Caracterización química del aceite y harina residual de solanum sisymbriifolium lam

    Directory of Open Access Journals (Sweden)

    Wiese, B.

    2001-04-01

    Full Text Available Seeds from Solanum sisymbriifolium Lam harvested at Olavarría (Buenos Aires, Argentine were defatted with hexane and the raw oil obtained with a yield of 20,6 % dry basis. The physicochemical characteristics of crude oil were: refractive index: 1,4610 (at 25ºC, iodine value: 112,8; saponification index: 170,0; unsaponifiable matter: 14,0 % and free fatty acid content: 2,4 (mg KOH/g. The fatty acid composition of seed oil was studied by gas-liquid chromatography. Major fatty acids of seed oil were: linoleic (52,3%, oleic (23,4 % and palmitic acid (16,4 %. The residual seed meal contained moderate level of crude protein (14,75%, dry basis, low level of available lysine (2,25 g/16gN and high content of crude fiber (51,5%, dry basis. Total and phytic acid phosphorous, calcium, ash, sugar and polysaccharides contents are reported.Semillas de Solanum sisymbriifolium Lam cosechadas en Olavarría (prov. de Buenos Aires, Argentina se trataron con hexano (soxhlet obteniéndose el aceite crudo (rendimiento:20,6% y la harina residual de extracción. Las características fisicoquímicas del aceite crudo fueron: Índice de refracción: 1.4610 (a 25ºC; Índice de iodo: 112,8; Índice de saponificación: 170,0; Insaponificable: 14,0%, Índice de acidez: 2,4 (mgKOH/g. Se determinó la composición acídica del aceite por cromatografía gas-líquido. Los ácidos grasos mayoritarios fueron: ácido linoleico (52,3%, ácido oleico (23,4% y ácido palmítico (16,4%. La harina residual de extracción contenía una moderada proporción de proteína cruda (14,75% b.s, baja proporción de lisina disponible (2,25 g/16gN y un alto contenido de fibra cruda (51,5 %b.s. Se informan valores de fósforo total y de ácido fítico, cenizas, calcio e hidratos de carbono.

  2. The Monitored Atherosclerosis Regression Study (MARS). Design, methods and baseline results.

    Science.gov (United States)

    Cashin-Hemphill, L; Kramsch, D M; Azen, S P; DeMets, D; DeBoer, L W; Hwang, I; Vailas, L; Hirsch, L J; Mack, W J; DeBoer, L

    1992-10-23

    67 years (mean age 57.9 years). For the cohort, baseline lipids are (mean +/- SD): TC, 231 +/- 24 mg/dL; low-density lipoprotein cholesterol (LDL-C) by ultracentrifugation, 153 +/- 24 mg/dL; LDL-C, by calculation, 157 +/- 23 mg/dL; high-density lipoprotein cholesterol (HDL-C), 43 +/- 10 mg/dL; and triglycerides, 160 +/- 73 mg/dL. There were no significant differences between treatment groups in baseline lipid levels or baseline angiographic characteristics. MARS baseline data show adequacy of randomization with comparability of lovastatin and placebo groups in demographic, lipid, and angiographic characteristics.

  3. Optimización del Proceso de Remoción de Metales Pesados de Agua Residual de la Industria Galvánica por Precipitación Química Optimization of the Removal Processs of Heavy Metals from Raw Water of Galvanic Industry by Chemical Precipitation

    Directory of Open Access Journals (Sweden)

    Eduardo Soto

    2006-01-01

    Full Text Available Se han estudiado las condiciones óptimas requeridas para remover metales pesados del agua residual de una industria galvánica, que contiene cromo (435 mg/L, zinc (720 mg/L, hierro (168 mg/L y níquel (24 mg/L. Se usó agua preparada en el laboratorio (agua sintética y agua de la industria misma (agua cruda. El tratamiento se hizo mediante precipitación química, usando sosa para ajustar el pH y cloruro férrico como aditivo coagulante en un equipo de prueba de jarras. Las condiciones óptimas encontradas usando el agua sintética fueron: 7 minutos para el tiempo de floculación, 18 rpm para la velocidad de agitación y 11.8 mL para la dosis de coagulante. Para el agua cruda fueron: 9.5 minutos para el tiempo de floculación, 30 rpm para la velocidad de agitación y 5.2 mL para la dosis de coagulante. Las condiciones de tratamiento fueron diferentes para el agua residual cruda, ya que el agua residual cruda contiene otros contaminantes, los cuales sobrecargan la superficie coloidal, esto afecta el proceso de floculaciónThe aim of this research was to obtain the optimum conditions to remove heavy metals from wastewaters of the galvanic industry, which contain chromium (435 mg/L, zinc (720 mg/L, iron (168 mg/L and nickel (24 mg/L. The treatment was made by chemical precipitation using caustic soda to set pH and ferric chloride like coagulant aid in jar test. The responses to optimize are: flocculation time, stirring speed and coagulant dose. The optimum conditions to remove heavy metals from synthetic wastewater was, flocculation time: 7 minutes, stirring speed: 18 rpm, coagulant dose: 11.8 mL and flocculation time: 9.5 minutes,stirring speed: 30 rpm, coagulant dose: 5.2 mL for raw wastewater. The treatment conditions were different for the raw wastewater because the raw wastewater contains other pollutants which over charge the colloidal surface and affects the flocculation processes

  4. The Synthesis of Multiple Polyaspartic Acid Water Treatment Agent and Study on Scale Inhibitor Performance of Calcium Carbonate%多元聚天冬氨酸水处理剂的合成及阻碳酸钙垢性能研究

    Institute of Scientific and Technical Information of China (English)

    杨玉华; 徐建宝; 王小龙; 苟振中

    2013-01-01

    以马来酸酐和碳酸铵为原料,热缩制备了绿色阻垢剂聚天冬氨酸(PASP),并用红外光谱对聚合物进行了表征.研制了一种无磷多元的绿色阻垢剂,其组成为聚天冬氨酸(PASP)、单宁酸(Tanic acid)和葡萄糖酸钠(Sodium gluconate).通过正交试验确定了该复合药剂的最佳配比.通过碳酸钙沉积法对PASP及其复合产品的阻垢性能进行了对比.结果表明:与PASP、Tanic acid或Sodium gluconate中的任意一种单剂以及PASP与Tanic acid或Sodium gluconate的二元复合水处理剂相比,PASP的三元复合水处理剂具有很好的阻碳酸钙垢的效果.当质量比,m(PASP)∶m(Tanic acid)∶m(Sodium gluconate)=1∶2∶3,总加量为24 mg·L-1时,阻垢率可达99.4%.实验结果为聚天冬氨酸的工业应用提供了参考价值.%As a green scale inhibitor,polyaspartic acid (PASP) was synthesized by thermal polymerization processes of maleic anhydride and ammonium carbonate and was characterized by means of infrared spectrometry (IR).A kind of green scale inhibitor was developed,and the main composition included PASP,tannic acid and sodium glucorote.The best ratio of this product was determined by orthogonal experiment.Scale inhibition performance of PASP and its compound products was compared by scale inhibition method against CaCO3.The results indicated that compared with single agent and the binary compound water treatment agent which was prepared by PASP with tannic acid or sodium gluconate,an excellent scale inhibitor against CaCO3 was obtained by ternary compound water treatment agent of PASP.When the mars ratio was m(PASP) ∶m(Tannic acid) ∶m(Sodium gluconate)=1∶2∶3,the scale inhibition rate can almost reach to 99.4%,and the total concentration was 24mg/L.The experimental results provided a valuable reference for industrial application of polyaspartic acid.

  5. 北五味子乙素体外抗氧化及抑菌作用的研究%Antioxidation and antimicrobial activity of the schisandrin B extraction from Schisandra chinensis( Turcz. )Baill

    Institute of Scientific and Technical Information of China (English)

    商红军; 孟宪军; 李斌; 朱力杰; 吴倩; 李元甦; 汪艳群

    2012-01-01

    Antioxidation and antimicrobial activities of the schisandrin B extraction from Schisandra chinensis(Turcz.) were studied.The results showed that schisandrin B had effective scavenging effect on the hydroxyl radical( ·OH) and the super oxideanion radical (O2-·). Scavenging effect of · OH( IC50 = 0.2mg·mL-1)was higher than that of the same concentration of Vc. Scavenging effect of O2-· (IC50 = 0.24mg·mL-1) was less than that of Vc. Schisandrin B had a certain activity against Staphylococcus aureus, Candida albicans, Salmonella, Ecoli, Bacillus subtilis.The activity against Candida albicans and Staphylococcus aureus was the strongest with minimum inhibitory concentration of 0.25 mg·mL-1. There was no activity on Rhizopus,Aspergillus niger and Nanyang yeast.%对北五味子乙素进行抗氧化及体外抑菌实验。结果表明:北五味子乙素对自由基的清除效果明显,其中对·OH清除作用大于相同浓度的VC,其半数清除浓度为0.2mg·mL-1;对O2-·清除作用小于VC,其半数清除浓度为0.24mg·mL-1。北五味子乙素提取液对金黄色葡萄球菌、白色念珠菌、沙门氏菌、大肠杆菌、枯草芽孢杆菌均有一定的抑制作用,其中对白色念珠菌和金黄色葡萄球菌的抑制作用最强,最低抑菌浓度为0.25mg·mL-1,对根霉、黑曲霉、南阳酵母无明显抑菌活性。

  6. 植物油提取五味子木脂素工艺的研究%Study on Extraction Process of Lignanoids from Shisandra chinesis(Turcz.)Baill by Vegetable Oil

    Institute of Scientific and Technical Information of China (English)

    徐仲航; 金向群

    2011-01-01

    通过正交试验,探讨植物油提取五味子木脂素新工艺及其工艺条件,并采用高效液相色谱技术测定提取物五味子甲素及五味子乙素含量.结果表明,影响植物油提取的主要因素是植物油用量B、提取次数C、提取时间A,其最佳提取工艺组合为A3B3C2;水提取、醇提取、超临界提取和植物油提取得到的提取物中五味子甲素及五味子乙素总量分别为3.24mg 、36.57mg、38.56mg和38.00mg,提取率分别为8.28%、93.1%、98.2%和96.8%.本研究确定了植物油提取五味子木脂素的新工艺;用新工艺提取得到的提取物中,五味子木脂素含量和提取率均较高;新工艺具有操作简便、无污染、条件温和等优点,对五味子的开发利用具有推广价值.%To investigate a new technology for extraction of lignanoids by vegetable oil, and compare it with other methods. Optimized con-diton with orthogonal design, we got the determination of schisandrin A and schisandrin B by High Performance Liquid Chromatography (HPLC). The main factors that influenced extraction were the amount of oil B, extracting times C, extracting time A. The best extraction process was A3B3C2. Total amount of schisandrin A and schisandrin B by the technology of water extraction, alcohol extraction, SFE-CO2 extraction and vegetable oil extraction was 3.24mg, 36.57mg, 38.56mg and 38.00mg, and extraction rate was 8.28%, 93.1%, 98.2% and 96.8% respectively. Establishtion of optimal technological process for lignanoids extraction by vegetable extraction, which provide several advantages such as simple work-up procedure, environmental friendliness and milder conditions, performs further exploitation and utilization prospect for Schisandra

  7. Comparative study on solubilities of bismuth, bismuth oxide,and bismuth sulfide in hydrochloric acid-thiourea%铋、氧化铋、硫化铋在盐酸-硫脲中溶解性的比较研究

    Institute of Scientific and Technical Information of China (English)

    马哈亚·艾斯江; 巴哈尔古丽·别克吐尔逊

    2012-01-01

    在盐酸介质中及55℃加热条件下,铋与硫脲形成黄色络合物,从而建立了用分光光度法比较铋、氧化铋、硫化铋在盐酸-硫脲中溶解性的新方法.研究了反应介质、试剂浓度、加热时间、加热温度、震荡速率等因素的影响.在最佳实验条件下,溶液的质量浓度为0.04~0.24 mg/mL时符合比尔定律.相关系数R=0.999 9,检出限为1.05×10-2 μg/mL,标准偏差SD=0.003 5,相对标准偏差RSD=2.42%,摩尔吸收系数为1.515×105 L/(mol·cm),加标回收率为96.7%~98.8%.实验结果表明,铋、氧化铋、硫化铋的溶解性顺序大小为:铋>氧化铋>硫化铋.%A yellow complex is formed from bismuth and thiourea in hydrochloric acid under the heated condition of 55 °C. Thus a new method is set up to compare the solubilities of bismuth, bismuth oxide, and bismuth sulfide in hydrochloric acid-thiourea by using spectrophotometry.Effects of factors, such as reaction medium, reagent concentration, heating time, heating temperature, and oscillation speed,were studied respectively .Under the optimum experimental conditions, mass concentration of the solution is in line with Beer's law, when it is within the range of 0.04-0.24 mg/mL.The correlation coefficient (R) is 0.999 9.The detection limit is 1.05xl0-2μg/mL.The standard deviation is 0.003 5.The relative standard deviation (RSD) is 2.42%.The molar absorption coefficient is 1.515xl05 L/(mol-cm).The recovery rate of standard addition is at 96.7%~98.8%. Experimental result showed that the solubilities of bismuth,bismuth oxide,and bismuth sulfide in hydrochloric acid-thiourea is in order by size as following: Bi>Bi2O3>Bi2S3.

  8. Development of doxorubicin-induced chronic cardiotoxicity in the B6C3F{sub 1} mouse model

    Energy Technology Data Exchange (ETDEWEB)

    Desai, Varsha G., E-mail: varsha.desai@fda.hhs.gov [Personalized Medicine Branch, Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Herman, Eugene H. [Division of Drug Safety Research, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993 (United States); Moland, Carrie L.; Branham, William S. [Personalized Medicine Branch, Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Lewis, Sherry M. [Office of Scientific Coordination, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Davis, Kelly J. [Toxicologic Pathology Associates, National Center for Toxicological Research, Jefferson, AR 72079 (United States); George, Nysia I. [Division Bioinformatics and Biostatistics, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Lee, Taewon [Department of Information and Mathematics, Korea University, Jochiwon, Chungnam 339-700 (Korea, Republic of); Kerr, Susan [Arkansas Heart Hospital, Little Rock, AR 72211 (United States); Fuscoe, James C. [Personalized Medicine Branch, Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States)

    2013-01-01

    Serum levels of cardiac troponins serve as biomarkers of myocardial injury. However, troponins are released into the serum only after damage to cardiac tissue has occurred. Here, we report development of a mouse model of doxorubicin (DOX)-induced chronic cardiotoxicity to aid in the identification of predictive biomarkers of early events of cardiac tissue injury. Male B6C3F{sub 1} mice were administered intravenous DOX at 3 mg/kg body weight, or an equivalent volume of saline, once a week for 4, 6, 8, 10, 12, and 14 weeks, resulting in cumulative DOX doses of 12, 18, 24, 30, 36, and 42 mg/kg, respectively. Mice were sacrificed a week following the last dose. A significant reduction in body weight gain was observed in mice following exposure to a weekly DOX dose for 1 week and longer compared to saline-treated controls. DOX treatment also resulted in declines in red blood cell count, hemoglobin level, and hematocrit compared to saline-treated controls after the 2nd weekly dose until the 8th and 9th doses, followed by a modest recovery. All DOX-treated mice had significant elevations in cardiac troponin T concentrations in plasma compared to saline-treated controls, indicating cardiac tissue injury. Also, a dose-related increase in the severity of cardiac lesions was seen in mice exposed to 24 mg/kg DOX and higher cumulative doses. Mice treated with cumulative DOX doses of 30 mg/kg and higher showed a significant decline in heart rate, suggesting drug-induced cardiac dysfunction. Altogether, these findings demonstrate the development of DOX-induced chronic cardiotoxicity in B6C3F{sub 1} mice. -- Highlights: ► 24 mg/kg was a cumulative cardiotoxic dose of doxorubicin in male B6C3F{sub 1} mice. ► Doxorubicin-induced hematological toxicity was in association with splenomegaly. ► Doxorubicin induced severe testicular toxicity in B6C3F{sub 1} male mice.

  9. Production of secondary particles and nuclei in cosmic rays collisions with the interstellar gas using the FLUKA code

    Science.gov (United States)

    Mazziotta, M. N.; Cerutti, F.; Ferrari, A.; Gaggero, D.; Loparco, F.; Sala, P. R.

    2016-08-01

    The measured fluxes of secondary particles produced by the interactions of Cosmic Rays (CRs) with the astronomical environment play a crucial role in understanding the physics of CR transport. In this work we present a comprehensive calculation of the secondary hadron, lepton, gamma-ray and neutrino yields produced by the inelastic interactions between several species of stable or long-lived cosmic rays projectiles (p, D, T, 3He, 4He, 6Li, 7Li, 9Be, 10Be, 10B, 11B, 12C, 13C, 14C, 14N, 15N, 16O, 17O, 18O, 20Ne, 24Mg and 28Si) and different target gas nuclei (p, 4He, 12C, 14N, 16O, 20Ne, 24Mg, 28Si and 40Ar). The yields are calculated using FLUKA, a simulation package designed to compute the energy distributions of secondary products with large accuracy in a wide energy range. The present results provide, for the first time, a complete and self-consistent set of all the relevant inclusive cross sections regarding the whole spectrum of secondary products in nuclear collisions. We cover, for the projectiles, a kinetic energy range extending from 0.1 GeV/n up to 100 TeV/n in the lab frame. In order to show the importance of our results for multi-messenger studies about the physics of CR propagation, we evaluate the propagated spectra of Galactic secondary nuclei, leptons, and gamma rays produced by the interactions of CRs with the interstellar gas, exploiting the numerical codes DRAGON and GammaSky. We show that, adopting our cross section database, we are able to provide a good fit of a complete sample of CR observables, including: leptonic and hadronic spectra measured at Earth, the local interstellar spectra measured by Voyager, and the gamma-ray emissivities from Fermi-LAT collaboration. We also show a set of gamma-ray and neutrino full-sky maps and spectra.

  10. RP-HPLC法测定奋乃静片的含量%Determination of perphenazine tablets by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    胡丹; 吕长淮; 吴玮; 尹创

    2012-01-01

    目的 建立RP-HPLC法测定奋乃静片的含量.方法 采用 Agilent C18色谱柱(5 μm,4.6 mm×150 mm),柱温为30℃,以甲醇-磷酸盐缓冲液(取磷酸二氢钾1.36 g,加水溶解并稀释成1 000 ml,加三乙胺4 ml,用磷酸调pH至3.02)(70:30)为流动相,流速为1 ml·min-1,检测波长为256 nm.结果奋乃静在8.048~40.24 mg·L-1的范围内线性关系良好(r=0.999 9,n=5),测得平均回收率为99.6%,RSD=1.09%(n=9).结论 该方法稳定可靠,重现性好,可有效控制奋乃静片的质量.%Objective To develop an HPLC method for the determination of the content of perphenazine tablets. Methods Agilent C18 column( 5μm,4. 6 mm x 150 mm )was used,the column temperature was 30℃,and the mobile phase was methanol-phosphate buffer solution ( 1. 36 g potassium dihydrogen phosphate dissolved and diluted into 1 000 ml by water,added with triethylamine 4 ml,adjusted to pH 3.02 with phosphoric acid ) ( 70:30 ) at the flow rate of 1. 0 ml · Min-1. The UV detection wavelength was 256 nm. Results The linear range was from 8.048 to 40. 24 mg · L-1( r =0. 999 9,n =5 ). The average recovery was 99.6% with RSD of 1.09% ( n = 9 ). Conclusion This method is stable,reliable and reproducible, which can be used for the quality control of perphenazine tablets.

  11. 秋季施肥对油松容器苗生长·氮吸收和抗寒性的影响%The Effect of Fall Fertilization on Pinus tabulaeformis Container Seedlings Growth, Nitrogen Uptake and Cold Tolerance

    Institute of Scientific and Technical Information of China (English)

    邹尚庆; 李国雷; 刘勇; 祝燕; 庞薇; 蒋乐; 史文辉

    2012-01-01

    [Objective]Study the effect of fall fertilization to Pinus tabulaeformis container seedlings growth,nitrogen uptake and cold tolerance. [ Method ] We make fall fertilization to Pinus tabulaeformis container seedlings , which have been processed in exponential fertilization level of 10, 40,80,and 120 mg/plants in the growing season ,set four treatment levels of 0 (control) ,12,24 and 48 mg/plants,seedlings will besed to do afforestation experiment after a growing season in the greenhouse cultivation in the following year. [Result] While fall fertilization of 24 mg/plants is the best treatment,under the treatment of 40E -24,N content was increased 15.9% compared to the control,cold resistance at -20 t has increased 95.2% ,afforestation effects are the best. [Conclusion]Fall fertilization can improve the nutrient content,cold tolerance and afforestation effects the following year. On the contrary,excessive fall fertilization (48 mg/plants)does not promote seedling growth but inhibit or damage.%[目的]研究秋季施肥对油松容器苗生长、氮吸收和抗寒性的影响.[方法]对在生长期经过不同指数施肥水平10、40、80和120mg/株处理过的油松容器苗进行秋季施肥,设置4个处理水平0(对照)、12、24和48 mg/株,苗木在温室培育一个生长季并在翌年进行造林试验.[结果]秋季施肥24 mg/株为最佳处理,在40E - 24处理下,N含量相比对照增加了15.9%,抗寒性在-20℃下更提高了95.2%,造林效果最佳.[结论]秋季施肥可有效提高苗木体内养分含量,抗寒性及翌年造林效果.但过量的秋季施肥(48 mg/株)并不促进苗木生长甚至有抑制或者损害作用.

  12. [Algae-removal effect of AS/PDM composite coagulants to winter Taihu Lake raw water].

    Science.gov (United States)

    Zhao, Xiao-Lei; Zhang, Yue-Jun; Li, Xiao-Xiao; Liu, Cheng; Zhu, Ling-Ling

    2009-04-15

    The series of stable AS/PDM composite coagulants prepared by polydimethyldiallylammonium chloride (PDM) and aluminium sulphate (AS) were used to research the algae-removal effect to winter Taihu Lake raw water. The effects of dosage of composite coagulants, composite mass ratios (20:1-5:1) of AS and PDM, intrinsic viscosity values (0.55-3.99 dL/g) of PDM on algae-removal rates were studied through coagulation and algae-removal experiments. The feasibility of using composite coagulants to substitute prechlorination process was analysed. The results show that when residual turbidity of 2 NTU to water after coagulation and sediment is required by water plant, the dosage (based on Al2O3) of AS, AS/PDM (0.55/20:1-3.99/5:1) composite coagulants are 4.24 mg/L, 3.96-1.87 mg/L, and the algae-removal rates are 83.00%, 87.52%-90.93% respectively. When dosage to raw water are 4.24 mg/L, the algae-removal rates of AS, AS/PDM (0.55/20:1-3.99/5:1) composite coagulants are 83.00%, 88.29%-97.66%, and the residual turbidities are 2.00 NTU, 1.76-0.43 NTU respectively. When dosage to chlorine-added water are 4.50 mg/L, the treatment effect of AS/PDM (1.53/10:1) composite coagulant to raw water is better than that of AS to chlorine-added water, and the treatment effect of AS/PDM (3.99/5:1) composite coagulant to raw water is better than that of AS, AS/PDM (0.55/20:1) and AS/PDM (1.53/10:1) composite coagulants to chlorine-added water. So using AS/PDM composite coagulants can enhance evidently the treatment effect of AS to winter Taihu Lake raw water. Compared with using AS solely, the dosage of AS in composite coagulants are saved when the residual turbidities are required in same level, and the treatment effect of AS is enhanced when the dosage of AS in composite coagulants are same as that of using AS solely. Moreover, using composite coagulants can replace the part chlorine-added function on increasing coagulation and algae-removal in prechlorination process and profitably increases

  13. Research on Bacteriostatic and Bactericidal Effect of Chlorine Dioxide on Aeromonas%二氧化氯对气单胞菌的抑菌和杀菌效果研究

    Institute of Scientific and Technical Information of China (English)

    谭凤霞; 吴全超

    2012-01-01

    Aeromonas bacteria strains, including the standard bacteria Aeromonas hydrophila and the Aeromonas bacteria strains which isolated from the culture water or diseased fish, were used to investigate the bacteriostatic and bactericidal efficacy of chlorine dioxide to Aeromonas bacterium by double broth dilution method. The results showed that the chlorine dioxide could inhibit the growth of bacterium at the lower concentration, and killed the bacterium at the higher concentration. The minimal inhibitory concentration (MIC) of chlorine dioxide to seven Aeromonas bacterium are 12 mg/L to strians ATCC7966, Ti, T3, T4, T5; and T6, and 24 mg/L to strain T2; The minimal bactericidal concentration (MBC) of chlorine dioxide to Aeromonas are 96 mg/L to strians ATCC7966, T1, T3 and T4, and 384 mg/L to strains T2, T5 and T6. These results provided the scientific basis for reasonable application of chlorine dioxide.%以嗜水气单胞菌(Aeromonas hydrophila)标准菌株ATCC7966和分离自养殖水环境及患病鲫鱼的气单胞菌(Aeromonas)为试验菌株,通过肉汤二倍稀释法研究二氧化氯的抑菌及杀菌效果.结果表明,二氧化氯在低浓度时能抑制气单胞菌的生长增殖,高浓度时能杀灭细菌,其对ATCC7966、T1、T3、T4、T5、T6菌株的最小抑菌浓度(MIC)为12 mg/L,对T2菌株的最小抑菌浓度为24 mg/L;二氧化氯对ATCC7966、T1、T3、T4菌株的最小杀菌浓度(MBC)为96 mg/L,对T2、T5、T6菌株的最小杀菌浓度为384 mg/L.研究结果能为二氧化氯在水产养殖上的合理使用提供一定的依据.

  14. Preparation of Hemp Stalk Activated Carbons for Decolorizing and Deodorizing of Bamboo Vinegar%汉麻杆活性炭的制备及对竹醋液脱色脱臭的研究

    Institute of Scientific and Technical Information of China (English)

    张婷; 高雅琳; 林小云; 周文富

    2012-01-01

    为了研究自制的汉麻活性炭对竹醋原液的脱色脱臭的最佳工艺,以单因素试验考察活性炭的用量、吸附时间、温度对竹醋原液(100℃蒸馏液)脱色脱臭的影响.结果表明:最佳工艺条件为单位体积竹醋原液汉麻活性炭用量24mg/mL,单位体积竹醋蒸馏液汉麻活性炭用量10mg/mL,吸附20min,吸附温度60℃,pH值为3.0,磷酸汉麻活性炭脱色率达85%以上;氯化锌脱色率达60%以上,磷酸汉麻活性炭吸附量高达385.3~427.3mg/g.结论:磷酸汉麻活性炭脱色率比其他活性炭脱色、脱臭率高,可应用于竹醋液的脱色脱臭.%The optimum process of decolorization and deodorization was studied, by using self-made hemp activated carbons and bamboo vinegar. The influence of adsorption dosage, time, and temperature on the decolorization and deodorization of bamboo vinegar liquid and its distillate(100℃) were explored by single factor. The results show that the optimum process conditions are. The hemp activated carbon is processed by phosphoric acid for bamboo vinegar liquid, dosage of activated carbons 24 mg/ml bamboo vinegar, dosage of activated carbons 10 mg/ml bamboo vinegar liquid and its distillate, adsorption time is 20 min, adsorption temperature is 60 ~C, pH=3.0, in this condition, the color removal rate of phosphoric acid processing hemp activated carbon is up to 85~; The color removal rate of zinc chloride processing hemp activated carbon is up to 60~/~o. The maximum adsorption of phosphoric acid processing hemp activated carbon is up to 358. 3~427.3 mg/g. The conclusion is drawn: The color removal rate and deodorizing rate of phosphoric acid processing activated carbon are higher than other activated carbons for the decolorization and deodorization of bamboo vinegar liquid.

  15. 固相萃取-高效液相色谱法检测药渣中残留泰乐菌素%Determination of tylosin residue in pharmaceutical waste using solid phase extraction-high performance liquid chromatography

    Institute of Scientific and Technical Information of China (English)

    王艳; 常璇; 马玉龙; 孙瑞珠; 王敏

    2013-01-01

    目的:建立了药渣中残留泰乐菌素的固相萃取-高效液相色谱测定方法.方法:药渣中残留泰乐菌素经甲醇提取,正己烷脱脂,C18固相萃取柱净化,然后用Agilent HC-C18反相色谱柱,紫外检测器,外标法定量检测.流动相为乙腈-0.02mol·L-1磷酸二氢钾溶液,等度洗脱,流速1 mL·min-1.结果:泰乐菌素含量在0.1 ~100 mg·L-1的范围内呈良好线性关系,在16,20,24 mg·L-1添加水平下的回收率为92.9% ~ 107.1%,RSD为2.4% ~4.1%,检出限为0.05 mg·L-1.结论:本法适用于药渣、饲料等样品中泰乐菌素残留量的测定.%Objective: To develop a method for the determination of tylosin residue in pharmaceutical waste using solid phase extraction ( SPE ) - high performance liquid chromatography with a UV detection system. Methods: Tylosin in pharmaceutical waste was extracted using methanol,defatted with hexane,purified on a C18 -SPE column, and then determined using C18 - reversed - phase column with external standard. The mobile phase was aceto-nitrile -0. 02 mol · L-1 phosphate buffer and the flow rate was 1. 0 mL · min-1 with isocratic elution. Results: The tylosin concentrations within the range of 0. 1 - 100 mg · L-1 exhibited a better linearity. The recoveries at spiked concentration of 16,20,24 mg · L-1 were in the range of 92. 9% -107. 1% , and the relative standard deviations were 2. 4% -4. 1%. The detection limit was 0. 05 mg · L-1. Conclusion: This method can be used utilization for the detection of tylosin residue in pharmaceutical waste and feed.

  16. Influence of Pu'er Tea Water Extracts on Artificial Caries Microhardness%普洱茶水浸液对人工龋齿显微硬度的影响

    Institute of Scientific and Technical Information of China (English)

    陈莹; 梁迎东; 杨华甫; 田富明; 蓝海

    2015-01-01

    Objective: To study the influence of the chemical composition of Pu'er tea on the hardness of the artificial caries. Methods:Put the bovine-cut-enamel into the demineralization solution pH=4 to remineralization to formulation artifical tooth decay. Select 72 demineralization bovine teeth, which hardness is about 310 kg/mm2, and put them into 12 groups in random:20 mg/L NaF group(positive control), deionized water group(negative control), and 96 mg/mL, 48 mg/mL, 24 mg/mL, 12 mg/mL, 6 mg/mL cooked tea group as well as raw tea groups same concentration as above. Use microhardness meter measure the hardness date of the cattle incisive after be handle by different solutions and observe the vary date of the microhardness of the surface enamel before and after remineralization. Results: The enamel demineralization samples were 96 mg/mL raw tea group, 48 mg/mL raw tea group, 24 mg/mL raw tea group, 96 mg/mL cooked tea group, 48 mg/mL cooked tea group, 20 mg/mL NaF group, after treatment, each group enamel hardness mean value was significantly higher than the baseline (P0.05). Conclusion:High concentrations of raw tea and cooked tea extract on enamel demineralization of bovine incisors were significantly promote remineralization and no significant difference(P>0.05), but not as good as remineralization 20 mg/mL NaF(P0.05).结论:高浓度的生茶、熟茶水浸液对脱矿牛切牙牙釉质均有显著促进再矿化作用且差异无统计学意义(P>0.05),但再矿化作用不如20 mg/mL NaF(P<0.05).

  17. Spectrophotometric Determination of Cefotaxime Sodium with Potassium Ferricyanide%用铁氰化钾分光光度法测定头孢噻肟钠

    Institute of Scientific and Technical Information of China (English)

    李晶; 张美芸; 李全民

    2011-01-01

    建立了以铁氰化钾测定头孢噻肟钠的分光光度法.在 0.20 mol/L NaOH 溶液中,头孢噻肟钠(CTX)于 100℃水浴中降解生成的巯基化合物能将 Fe(Ⅲ)(pH=3.0)还原为Fe(Ⅱ),根据Fe(Ⅱ)与K3[Fe(CN)6]反应生成可溶性普鲁士蓝(KFeⅢ[FeⅡ(CN)6])的吸光度,可以间接测定头孢噻肟钠的含量.头孢噻肟钠在0.040~24 mg/L 范围内与吸光度(A)呈线性关系,线性回归方程:A=0.05088+0.2166ρ(mg/L),相关系数R=0.9986,检出限为0.01 mg/L,相对标准偏差(RSD)为1.36%(n=11),表观摩尔吸光系数ε=2.3 ×105 L/(mol·cm).此方法可用于药物及血清中头孢噻肟钠含量的测定.%A spectrophotometric method has been set up to determine cefotaxime sodium using potassium ferricyanide as the spectroscopic probe reagent. With the presence of potassium ferricyanide, the degradation product of cefotaxime sodium can reduce Fe3+ to Fe2 + at pH 3.0, which facilitate the formation of soluble Prussian Blue ( KFeⅢ [ Fe Ⅱ( CN ) 6 ] ). The absorbance of soluble Prussian Blue is measured at its absorption maximum of 730 nm and the amount of cefotaxime sodium can be indirectly calculated. Under optimized conditions, a good linear relationship is obtained in the range of 0. 040 ~ 24 mg/L of cefotaxime sodium. The linear regression equation is A =0. 05088 +0. 2166ρ( mg/L) with linear correlation coefficient of 0. 9986. The detection limit and relative standard deviation are 0.01 mg/L and 1.36% , respectively. Tthe apparent molar absorption coefficient of indirect determination of cefotaxime sodium is 2. 3 x 105 L/(mol·cm). This method has been successfully applied to the determination of cefotaxime sodium in pharmaceutical and serum samples.

  18. Role of organic matter on aggregate stability and related mechanisms through organic amendments

    Science.gov (United States)

    Zaher, Hafida

    2010-05-01

    To date, only a few studies have tried to simultaneously compare the role of neutral and uronic sugars and lipids on soil structural stability. Moreover, evidence for the mechanisms involved has often been established following wetting of moist aggregates after various pre-treatments thus altering aggregate structure and resulting in manipulations on altered aggregates on which the rapid wetting process may not be involved anymore. To the best of our knowledge, the objective of this work was to study the role of neutral and uronic sugars and lipids in affecting key mechanisms (swelling rate, pressure evolution) involved in the stabilization of soil structure. A long-term incubation study (48-wk) was performed on a clay loam and a silty-clay loam amended with de-inking-secondary sludge mix at three rates (8, 16 and 24 Mg dry matter ha-1), primary-secondary sludge mix at one rate (18 Mg oven-dry ha-1) and composted de-inking sludge at one rate (24 Mg ha-1). Different structural stability indices (stability of moist and dry aggregates, the amount of dispersible clay and loss of soil material following sudden wetting) were measured on a regular basis during the incubation, along with CO2 evolved, neutral and uronic sugar, and lipid contents. During the course of the incubations, significant increases in all stability indices were measured for both soil types. In general, the improvements in stability were proportional to the amount of C added as organic amendments. These improvements were linked to a very intense phase of C mineralization and associated with increases in neutral and uronic sugars as well as lipid contents. The statistical relationships found between the different carbonaceous fractions and stability indices were all highly significant and indicated no clear superiority of one fraction over another. Paper sludge amendments also resulted in significant decreases in maximum internal pressure of aggregate and aggregate swelling following immersion in water

  19. Oregano essential oil-pectin edible films as anti-quorum sensing and food antimicrobial agents

    Science.gov (United States)

    Alvarez, Maria V.; Ortega-Ramirez, Luis A.; Gutierrez-Pacheco, M. Melissa; Bernal-Mercado, A. Thalia; Rodriguez-Garcia, Isela; Gonzalez-Aguilar, Gustavo A.; Ponce, Alejandra; Moreira, Maria del R.; Roura, Sara I.; Ayala-Zavala, J. Fernando

    2014-01-01

    Edible films can be used as carriers for antimicrobial compounds to assure food safety and quality; in addition, pathogenesis of food bacteria is related to a cell to cell communication mechanism called quorum sensing (QS). Oregano essential oil (OEO) has proved to be useful as food antimicrobial; however, its food applications can be compromised by the volatile character of its active constituents. Therefore, formulation of edible films containing OEO can be an alternative to improve its food usages. QS inhibitory activity of OEO and pectin-OEO films was evaluated using Chromobacterium violaceum as bacterial model. Additionally, antibacterial activity was tested against Escherichia coli O157:H7, Salmonella Choleraesuis, Staphylococcus aureus, and Listeria monocytogenes. OEO was effective to inhibit bacterial growth at MIC of 0.24 mg/mL for all tested bacteria and MBC of 0.24, 0.24, 0.48, and 0.24 mg/mL against E. coli O157:H7, S. Choleraesuis, S. aureus, and L. monocytogenes, respectively. Pectin-films incorporated with 36.1 and 25.9 mg/mL of OEO showed inhibition diameters of 16.3 and 15.2 mm for E. coli O157:H7; 18.1 and 24.2 mm for S. Choleraesuis; 20.8 and 20.3 mm for S. aureus; 21.3 and 19.3 mm for L. monocytogenes, respectively. Pectin-OEO film (15.7 mg/mL) was effective against E. coli O157:H7 (9.3 mm), S. aureus (9.7 mm), and L. monocytogenes (9.2 mm), but not for S. Choleraesuis. All concentrations of OEO (0.0156, 0.0312, 0.0625 and 0.125 mg/mL) and pectin-OEO films (15.7, 25.9 and 36.1 mg/mL) showed a significant anti-QS activity expressed as inhibition of violacein production by C. violaceum. Additionally, the application of pectin-OEO films was effective reducing total coliforms, yeast, and molds of shrimp and cucumber slices stored at 4°C during 15 d. These results demonstrated the potential of pectin films enriched with OEO as food related microorganisms and QS inhibitors. PMID:25566215

  20. Extreme early solar system chemical fractionation recorded by alkali-rich clasts contained in ordinary chondrite breccias

    Science.gov (United States)

    Yokoyama, Tatsunori; Misawa, Keiji; Okano, Osamu; Shih, Chi-Yu; Nyquist, Laurence E.; Simon, Justin I.; Tappa, Michael J.; Yoneda, Shigekazu

    2017-01-01

    New K-Ca and Rb-Sr isotopic analyses have been performed on alkali-rich igneous rock fragments in the Yamato (Y)-74442 and Bhola LL-chondritic breccias to better understand the extent and timing of alkali enrichments in the early solar system. The Y-74442 fragments yield a K-Ca age of 4.41 ± 0.28 Ga for λ(40K) = 0.5543 Ga-1 with an initial 40Ca/44Ca ratio of 47.1618 ± 0.0032. Studying the same fragments with the Rb-Sr isotope system yields an age of 4.420 ± 0.031 Ga for λ(87Rb) = 0.01402 Ga-1 with an initial ratio of 87Sr/86Sr = 0.7203 ± 0.0044. An igneous rock fragment contained in Bhola shows a similar alkali fractionation pattern to those of Y-74442 fragments but does not plot on the K-Ca or Rb-Sr isochron of the Y-74442 fragments. Calcium isotopic compositions of whole-rock samples of angrite and chondrites are primordial, indistinguishable from mantle-derived terrestrial rocks, and here considered to represent the initial composition of bulk silicate Earth. The initial ε40Ca value determined for the source of the alkali clasts in Y-74442 that is ∼0.5 ε-units higher than the solar system value implies an early alkali enrichment. Multi-isotopic studies on these alkali-rich fragments reveal that the source material of Y-74442 fragments had elemental ratios of K/Ca = 0.43 ± 0.18, Rb/Sr = 3.45 ± 0.66 and K/Rb ∼ 170, that may have formed from mixtures of an alkali-rich component (possibly an alkali-enriched gaseous reservoir produced by fractionation of early nebular condensates) and chondritic components that were flash-heated during an impact event on the LL-chondrite parent body ∼4.42 Ga ago. Further enrichments of potassium and rubidium relative to calcium and strontium as well as a mutual alkali-fractionation (K/Rb ∼ 50 and heavier alkali-enrichment) would have likely occurred during subsequent cooling and differentiation of this melt. Alkali fragments in Bhola might have undergone similar solid-vapor fractionation processes to those of Y