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111.
Aiello GL 《Nonlinear dynamics, psychology, and life sciences》2012,16(1):23-35
A special case of deterministic chaos that is independent of the architecture of the connections has been observed in a computer model of a purely excitatory neuronal network. Chaos onsets when the level of connectivity is critically low. The results indicate a typical period-doubling route to chaos as the connectivity decreases. A cognitive interpretation of such type of chaos, based on information theory and phase-transitions, is proposed. 相似文献
112.
Giovanna Calò Gaetano Bellanca Ali Emre Kaplan Paolo Bassi Vincenzo Petruzzelli 《Optical and Quantum Electronics》2018,50(6):261
In this paper we present a double plasmonic Vivaldi antenna for on-chip optical wireless communication. The proposed antenna is a two-element broadside array fed by a silicon waveguide. The designs of the power splitter and of the hybrid Si-plasmonic coupler used for antenna excitation are described in detail. The array radiation characteristics are optimized through Finite Difference Time Domain simulations and the performance of a point-to-point link is evaluated. The proposed double Vivaldi array increases the gain of 3 dB with respect to a single antenna, improving the received power on a link of 6 dB when the double antenna is used for both transmitting and receiving sections. 相似文献
113.
Aurore Fraix Vanna Torrisi Giovanni Marletta Salvatore Sortino Placido G. Mineo Gaetano A. Tomaselli 《Supramolecular chemistry》2016,28(5-6):485-492
AbstractA poly(p-phenyleneethynylene) polymer (PCF[5]), bearing two π-rich cone-like calix[5]arene cavities (assembling cores) attached to a rigid p-phenyleneethynylene spacer, was synthesised by a Pd-catalysed cross-coupling reaction. UV–vis absorption and fluorescence spectroscopies combined with dynamic light scattering measurements provide evidence for the self-assembly of PCF[5] (homopolytopic host molecule) with a complementary C60 fulleropyrrolidine (C60-Pyr) guest in solution, in the construction of a supramolecular polymer network. Atomic force microscopy analysis of PCF[5]/C60-Pyr highlights the formation of a bicontinuous network consisting of a uniform distribution of prominent structures, within a polymeric background forming a biphasic structure. 相似文献
114.
Alberto Parini Giovanna Calò Gaetano Bellanca Vincenzo Petruzzelli 《Optical and Quantum Electronics》2014,46(3):385-396
This paper presents two different approaches that may allow the optical interconnection between superposed levels of multilayer photonic circuits as, for example, in optical-networks-on-chip. The first configuration is based on multi-mode interference devices, while the second one exploits multiple stacked directional couplers. The issues concerning the analytical and numerical design of such devices are discussed, together with a performance analysis in terms of efficiency and footprint. 相似文献
115.
Francesco D’Andrea Gaetano Fiore Davide Franco 《Letters in Mathematical Physics》2014,104(11):1425-1443
Using the Weil–Brezin–Zak transform of solid state physics, we describe line bundles over elliptic curves in terms of Weyl operators. We then discuss the connection with finitely generated projective modules over the algebra A θ of the noncommutative torus. We show that such A θ -modules have a natural interpretation as Moyal deformations of vector bundles over an elliptic curve E τ , under the condition that the deformation parameter θ and the modular parameter τ satisfy a non-trivial relation. 相似文献
116.
Gaetano Corso Monica Gelzo Angela Chambery Valeria Severino Antimo Di Maro Filomena Schiano Lomoriello Oceania D'Apolito Antonio Dello Russo Patrizia Gargiulo Ciro Piccioli Paolo Arcari 《Journal of separation science》2012,35(21):2986-2993
Spectroscopic and MS techniques were used to characterize the pigments and the composition of polar and nonpolar binders of a stray wall painting fragment from Liternum (Italy) archaeological excavation. X‐ray fluorescence and diffraction analysis of the decorations indicated mainly the presence of calcite, quartz, hematite, cinnabar, and cuprorivaite. Infrared spectroscopy, GC coupled to flame‐ionization detector, and MS analysis of the polar and nonpolar components extracted from paint layers from three different color regions revealed the presence of free amino acids, sugars, and fatty acids. Interestingly, LC‐MS shotgun analysis of the red painting region showed the presence of αS1‐casein of buffalo origin. Compared to our previous results from Pompeii's wall paintings, even though the Liternum painting mixture contained also binders of animal origin, the data strongly suggest that in both cases a tempera painting technique was utilized. 相似文献
117.
Guarino G Rastrelli F Scrimin P Mancin F 《Journal of the American Chemical Society》2012,134(17):7200-7203
Gd(3+) ions, once bound to the monolayer of organic molecules coating the surface of gold nanoparticles, produce a paramagnetic relaxation enhancement (PRE) that broadens and eventually cancels the signals of the nuclear spins located nearby (within 1.6 nm distance). In the case of nanoparticles coated with mixed monolayers, the signals arising from the different coating molecules experience different PRE, depending on their distance from the binding site. As a consequence, observation of the signal broadening patterns provides direct information on the monolayer organization. 相似文献
118.
Gaetano Guerra Christophe Daniel Paola Rizzo Oreste Tarallo 《Journal of Polymer Science.Polymer Physics》2012,50(5):305-322
Polymeric “cocrystalline forms,” that is, structures were a polymeric host and a low‐molecular‐mass guest are cocrystallized, were early recognized, and in many cases also well characterized by X‐ray diffraction studies. However, only in the last two decades cocrystalline forms have received attention in material science, due to the ability (of few of them) to maintain an ordered polymer host structure even after guest removal, thus leading to the formation of “nanoporous‐crystalline forms,” for which many applications in the fields of molecular separation and sensors have been proposed. Moreover, in the last decade, an accurate control of the orientation of the polymer cocrystalline phases has been achieved, thus leading to a control of the orientation of the guest molecules, not only in the crystalline phase but also in macroscopic films. In addition, on the basis of this orientation control, in the last few years, cocrystalline films where active molecules are present as guests of polymer cocrystalline phases have been proposed for optical, magnetic and electric applications. In the last few years, it has been also discovered that polymer cocrystallization, when induced by nonracemic guest molecules, can produce stable chiral optical films. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
119.
Andrea Pappalardo Maria E. Amato Francesco P. Ballistreri Anna Notti Gaetano A. Tomaselli Rosa M. Toscano Giuseppe Trusso Sfrazzetto 《Tetrahedron letters》2012,53(52):7150-7153
Chiral diastereomeric cavitand-salen macrocycles have been synthesized by the high-dilution condensation of a tris-(quinoxaline-bridged)-diformyl-calix[4]resorcarene with (1R,2R)-diphenylethylenediamine. The reaction produced a couple of diastereoisomers, consisting of two cavitand cavities bis-bridged by two chiral diimino moieties, which differ in a convergent (C-shaped) or divergent (S-shaped) orientation of the two cavities. 相似文献
120.
A Pappalardo ME Amato FP Ballistreri GA Tomaselli RM Toscano G Trusso Sfrazzetto 《The Journal of organic chemistry》2012,77(17):7684-7687
A pair of diastereomeric salen cavitands and their uranyl complexes combine a chiral (R,R) salen bridge and an inherent chiral tris-bridged quinoxaline cup within the same molecule. Whereas the free ligands show a preference for the same enantiomer of an α-amino acid pair, the corresponding UO(2) complexes display opposite enantiodiscrimination and exceptionally high enantioselectivities (K(D)/K(L) = 26.4). 相似文献