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991.
Angelo Simonini 《Monatshefte für Chemie / Chemical Monthly》1893,14(1):81-92
Ohne Zusammenfassung 相似文献
992.
R. Bernabei P. Belli F. Cappella R. Cerulli C. J. Dai A. d’Angelo H. L. He A. Incicchitti H. H. Kuang J. M. Ma F. Montecchia F. Nozzoli D. Prosperi X. D. Sheng Z. P. Ye 《The European Physical Journal C - Particles and Fields》2008,56(3):333-355
The highly radiopure ≃ 250 kg NaI(Tl) DAMA/LIBRA set-up is running at the Gran Sasso National Laboratory of the INFN. In this
paper the first result obtained by exploiting the model independent annual modulation signature for Dark Matter (DM) particles
is presented. It refers to an exposure of 0.53 ton×yr. The collected DAMA/LIBRA data satisfy all the many peculiarities of
the DM annual modulation signature. Neither systematic effects nor side reactions able to account for the observed modulation
amplitude and to contemporaneously satisfy all the several requirements of this DM signature are available. Considering the
former DAMA/NaI and the present DAMA/LIBRA data all together (total exposure 0.82 ton×yr), the presence of Dark Matter particles
in the galactic halo is supported, on the basis of the DM annual modulation signature, at 8.2 σ C.L.; in particular, in the energy interval (2–6) keV, the modulation amplitude is (0.0131±0.0016) cpd/kg/keV and the phase
and the period are well compatible with June 2
nd
and one year, respectively. 相似文献
993.
Analytical and numerical approaches to nonlinear galloping of internally resonant suspended cables 总被引:2,自引:0,他引:2
A study is carried out on nonlinear multimodal galloping of suspended cables. A consistent model of a curved cable-beam, geometrically nonlinear and able to torque, recently formulated by the authors, is used. The model accounts for quasi-steady aerodynamic forces, including the effect of static swing of the cable and dynamic twist of the cross-section. Complementary solution methods are employed, namely, finite-difference and Galerkin spatial discretization, followed by numerical time-integration, or Galerkin spatial discretization in conjunction with Multiple Scale perturbation analysis. The different techniques are applied to a cable close to the first cross-over point, at which a number of internal resonances exist. Branches of periodic solutions and their stability are evaluated as functions of wind velocity. The existence of branches of quasi-periodic solutions, originating from narrow unstable intervals and propagating elsewhere, is also proved. Qualitative and quantitative results furnished by the different investigation tools are compared among them, and the importance of the various components of motion, accounted or neglected in the reduced models, is discussed. 相似文献
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995.
Andrea Ravasio Laura Boggioni Incoronata Tritto Cristina D'arrigo Angelo Perico Julia Hitzbleck Jun Okuda 《Journal of polymer science. Part A, Polymer chemistry》2009,47(21):5709-5719
The in situ synthesis of ethylene‐co‐norbornene copolymers/multi‐walled carbon nanotubes (MWNTs) nanocomposites was achieved by rare‐earth half‐sandwich scandium precursor [Sc(η5‐C5Me4SiMe3)(η1‐CH2SiMe3)2(THF)] (1) activated by [Ph3C][B(C6F5)4], through a non‐PFT (Polymerization Filling Technique) approach. MWNTs nanocomposites with low aluminum residue were obtained with excellent yields even though small amounts of triisobutylaluminium were needed as scavenger to prevent catalyst poisoning by MWNT impurities. MWNT bundles were disaggregated and highly coated with Poly(ethylene‐co‐norbornene) [P(E‐co‐N)] as revealed by transmission electron microscopy. Interestingly, P(E‐co‐N) copolymers showed Tg over 130 °C as well as norbornene content over 50 mol %; both values were higher than those obtained by the cationic active species in 1 /[Ph3C][B(C6F5)4]. A series of copolymerization reactions by 1 /[Ph3C][B(C6F5)4]/AliBu3 without MWNTs produced copolymers with the same unexpected features. The NMR analysis revealed the presence of rac‐ENNE and rac‐ENNNE sequences. Thus, AliBu3 changed the stereoirregular alternating copolymer microstructure produced by 1 /[Ph3C][B(C6F5)4]. We conclude that AliBu3 is not only a scavenger for CNT impurities, but it reacts with the THF ligand to give coordinatively unsaturated active species. Finally, P(E‐co‐N)/MWNT masterbatches were mixed with commercial TOPAS to produce cyclic olefin copolymer nanocomposites with excellent dispersion of filler. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5709–5719, 2009 相似文献
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998.
Chiara Guarino Fabio Fuselli Alessandro La Mantia Lucia Longo Angelo Faberi Rosa Maria Marianella 《Rapid communications in mass spectrometry : RCM》2010,24(6):705-713
A common fraud in the dairy field is the addition of sheep's milk to goat's cheeses, because it has a very similar taste to goat's milk, but is more available, and is commonly considered to have a better capacity to curdle. For similar reasons, and due to economic convenience, sheep's cheeses may also contain fraudulent cow's milk. In order to detect this fraud, an EU official method may be used, but it is only a qualitative method (presence/absence of cow's milk). A method able to quantify the presence of sheep's milk during cheese production in goat's and cow's cheeses was developed. The method is based on liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) analysis of peptides of a casein extract from the cheese. By a simple procedure, caseins are extracted from cheeses, solubilized, digested with plasmin, and subsequently analyzed by LC/ESI‐MS/MS. A typical sheep's peptide produced by plasmin hydrolysis (m/z = 860) was accurately selected and analyzed to understand if, and by how much, a declared pure goat's cheese contains sheep's milk. By analyzing the same peptide it is also possible to detect if, and by how much, a declared pure sheep's milk contains, or not, cow's milk. The method was applied to several goat's and cow's cheese samples. Quantitation was performed with a calibration curve obtained by analyzing curd cheeses containing different percentages of sheep's milk. The method detection limit and method quantitation limit were evaluated. This method appears accurate and suitable for detecting up to 2% of sheep's milk in cheeses. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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