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381.
Campidelli S Ballesteros B Filoramo A Díaz DD de la Torre G Torres T Rahman GM Ehli C Kiessling D Werner F Sgobba V Guldi DM Cioffi C Prato M Bourgoin JP 《Journal of the American Chemical Society》2008,130(34):11503-11509
We describe the functionalization of single-wall carbon nanotubes (SWNTs) with 4-(2-trimethylsilyl)ethynylaniline and the subsequent attachment of a zinc-phthalocyanine (ZnPc) derivative using the reliable Huisgen 1,3-dipolar cycloaddition. The motivation of this study was the preparation of a nanotube-based platform which allows the facile fabrication of more complex functional nanometer-scale structures, such as a SWNT-ZnPc hybrid. The nanotube derivatives described here were fully characterized by a combination of analytical techniques such as Raman, absorption and emission spectroscopy, atomic force and scanning electron microscopy (AFM and SEM), and thermogravimetric analysis (TGA). The SWNT-ZnPc nanoconjugate was also investigated with a series of steady-state and time-resolved spectroscopy experiments, and a photoinduced communication between the two photoactive components (i.e., SWNT and ZnPc) was identified. Such beneficial features lead to monochromatic internal photoconversion efficiencies of 17.3% when the SWNT-ZnPc hybrid material was tested as photoactive material in an ITO photoanode. 相似文献
382.
383.
Spiess S Welter C Franck G Taquet JP Helmchen G 《Angewandte Chemie (International ed. in English)》2008,47(40):7652-7655
384.
Tiwari KN Monserrat JP Hequet A Ganem-Elbaz C Cresteil T Jaouen G Vessières A Hillard EA Jolivalt C 《Dalton transactions (Cambridge, England : 2003)》2012,41(21):6451-6457
Two series of ten chalcones and ten aurones, where ferrocene replaces the C ring and with diverse substituents on the A ring were synthesized. The compounds were tested against two antibiotic-sensitive bacterial strains, E. coli ATCC 25922 and S. aureus ATCC 25923, and two antibiotic-resistant strains, S. aureus SA-1199B and S. epidermidis IPF896. The unsubstituted compound and those with methoxy substitution showed an inhibitory effect on all bacterial strains at minimum inhibitory concentrations ranging between 2 and 32 mg L(-1). For four of these compounds, the effect was bactericidal, as opposed to bacteriostatic. The corresponding organic aurones did not show growth inhibition, underscoring the role of the ferrocene group. The methoxy-substituted aurones and the unsubstituted aurone also showed low micromolar (IC(50)) activity against MRC-5 non-tumoral lung cells and MDA-MB-231 breast cancer cells, suggesting non-specific toxicity. 相似文献
385.
Khan S Samuel PP Michel R Dieterich JM Mata RA Demers JP Lange A Roesky HW Stalke D 《Chemical communications (Cambridge, England)》2012,48(40):4890-4892
Herein we report the syntheses of terminal Sn(II) (3) and Ge(II) (4) hydrides from the corresponding chloride precursors [{2,6-iPr(2)C(6)H(3)NCMe}(2)C(6)H(3)MCl] (M = Sn (1), Ge (2)) using [K{B(sec-Bu)(3)}H] as a hydrogenating agent. Combination of steric shielding and intramolecular N → M interactions resulted in the protection of M(II)-H bonds. 相似文献
386.
Jean-Philippe Anker Vittoria Pierfelice Maria Vallarino 《Journal of Differential Equations》2012,252(10):5613-5661
We study the dispersive properties of the wave equation associated with the shifted Laplace–Beltrami operator on real hyperbolic spaces and deduce new Strichartz estimates for a large family of admissible pairs. As an application, we obtain local well-posedness results for the nonlinear wave equation. 相似文献
387.
We show that if a solution of a sub-analytic differential equation admits an asymptotic expansion , , then the exponents belong to a finitely generated semi-group of . We deduce a similar result for the components of non-oscillating trajectories of real analytic vector fields in dimension n. To cite this article: M. Matusinski, J.-P. Rolin, C. R. Acad. Sci. Paris, Ser. I 342 (2006). 相似文献
388.
Hansen AL Ebran JP Gøgsig TM Skrydstrup T 《Chemical communications (Cambridge, England)》2006,(39):4137-4139
A combination of Ni(COD)(2) and PCy(3) promotes effectively the Suzuki-Miyaura cross coupling of 1-arylalkenyl phosphates with aryl boronic acids with yields attaining 99%. 相似文献
389.
Maria-Agatha Gunawan Chunjing Qiao Isabelle Abrunhosa-Thomas Bertrand Puget Jean-Philippe Roblin Damien Prim Yves Troin 《Tetrahedron letters》2010,51(41):5392-4086
A series of pyridylmethylamines have been synthesized in one step from commercially available starting material and identified as effective ligands for Pd-catalyzed carbon-carbon bond formation through Suzuki-Miyaura coupling reaction. The N,N-pyridylmethylamine-Pd catalytic systems appeared as an interesting and robust compromise between catalytic efficiency, substrate compatibility, and practical aspects. 相似文献
390.
Vincent De Waele Uli Schmidhammer Jean-Raphaël Marqus Hugues Monard Jean-Philippe Larbre Nicolas Bourgeois Mehran Mostafavi 《Radiation Physics and Chemistry》2009,78(12):1099-1101
A single-shot electro-optic (EO) diagnostic has been installed on the ELYSE photocathode RF gun accelerator to monitor the electron bunch at the place and under the conditions of the ps pulse radiolysis experiments. The EO signal is due to the coulombic field of the electron bunch and to a contribution of a free-space THz radiation generated by the same electron pulse. This signal is recorded shot-to-shot at the repetition rate of the accelerator. The jitter of the arrival time of the electron bunch is characterized for the first time with a non-invasive method and is confirmed to be around 1 ps. 相似文献