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Noufal Kandoth Milo Malanga Dr. Aurore Fraix Dr. László Jicsinszky Dr. Éva Fenyvesi Tiziana Parisi Ivana Colao Dr. Maria Teresa Sciortino Prof. Salvatore Sortino 《化学:亚洲杂志》2012,7(12):2888-2894
Herein we report the design, preparation, and properties of a supramolecular system based on a tailored nitric oxide (NO) photodonor and a rhodamine‐labeled β‐cyclodextrin conjugate. The combination of spectroscopic and photochemical experiments shows the absence of significant interchromophoric interactions between the host and the guest in the excited states. As a result, the complex is able to release NO under the exclusive control of visible light, as unambiguously demonstrated by direct detection of this transient species through an amperometric technique, and exhibits the typical red fluorescence of the rhodamine appendage. The supramolecular complex effectively internalizes in HeLa cancer cells as proven by fluorescence microscopy, shows a satisfactory biocompatibility in the dark, and induces about 50 % of cell mortality upon irradiation with visible light. The convergence of all these properties in one single complex makes the present host–guest ensemble an appealing candidate for further delevopment of photoactivatable nanoscaled systems addressed to photostimulated NO‐based therapy. 相似文献
254.
Steady combustion waves in one space dimension are studied by means of fluid-dynamic reactive Navier?CStokes equations derived from kinetic theory. By using the conservation laws, the problem is reduced to a three-dimensional dynamical system, with different solutions of deflagration or detonation type according to several various sub-regions in the parameter space. The delicate question of the flame eigenvalue is addressed, and a suitable numerical algorithm is used in order to catch these special solutions and to deal with the relevant unstable equilibrium states. Numerical examples of smooth weak deflagrations or detonations are shown. 相似文献
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We demonstrate an all-optical scheme for the simultaneous drop and wavelength conversion of bursts of data from a continuous stream of differential phase-shift keyed (DPSK) signals. This function is obtained in a single semiconductor optical amplifier Mach-Zehnder interferometer thanks to proper nonlinear interaction of the data stream and an optical gate signal at different wavelength. Fast switching-time enabling wavelength shifting operation on continuous DPSK data stream at 10 and 40 Gb/s without any bit loss is reported. Corresponding measured power penalties are negligible at 10 Gb/s and about 1.7 dB at 40 Gb/s. 相似文献
257.
Luigi Brambilla Giuseppe Zerbi Stefano Nascetti Fabrizio Piemontesi Giampiero Morini 《Macromolecular Symposia》2004,213(1):287-302
The vibrational Infrared and Raman Spectra of a MgCl2-TiCl4 Ziegler-Natta catalyst precursor with a 50/1 MgCl2/TiCl4 ratio have been recorded. The Raman spectrum of this catalyst precursor, in the range 50-500 cm−1, shows clear scattering lines which can be assigned to the complex MgCl2-TiCl4, well separated from those of the initial species. Analogous, but less clear signals can be found in the infrared spectrum. Vibrational symmetry analysis and quantum chemical calculations of suitable models of MgCl2-TiCl4 complex have been made for the interpretation of the experimentally recorded spectra. The observed spectroscopic signals can be explained in terms of the existence of only one type of MgCl2-TiCl4 complex where the TiCl4 molecules are complexed on the MgCl2 along the (110) lateral cuts in a local C2v symmetry with the Ti atoms in an octahedral coordination. 相似文献