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61.
Talarico AM Szerb EI Mastropietro TF Aiello I Crispini A Ghedini M 《Dalton transactions (Cambridge, England : 2003)》2012,41(16):4919-4926
Synthesis, crystal structural determination and photophysical properties of a series of heteroleptic cationic cyclometalated iridium(III) derivatives of general formula [(ppy)(2)Ir(en)]X (X = ClO(4)(-) (1), PF(6)(-) (2), Cl(-) (3), BPh(4)(-) (4)), are described. The assembly of the common molecular building block allows to get highly luminescent crystalline materials or to assemble poorly luminescent supramolecular channelled architectures, for which the additional contribution of oxygen quenching effects has been observed. Moreover, the high reproducibility of the preparations of the crystalline materials in their specific crystalline phases, makes the control of the supramolecular organization of photo-active iridium(III) complexes within the crystalline structures a useful synthetic procedure for the construction of highly luminescent materials. 相似文献
62.
Oliveri V Giuffrida ML Vecchio G Aiello C Viale M 《Dalton transactions (Cambridge, England : 2003)》2012,41(15):4530-4535
8-Hydroxyquinolines are systems of great interest in the field of inorganic and bioinorganic chemistry. They are metal-binding compounds and are known to exhibit a variety of biological activities, such as antibacterial and anticancer activities. Among these systems, clioquinol has been the focus of a renewed interest in recent years. In this scenario, we synthesized and characterized the new clioquinol glucoconjugate, 5-chloro-7-iodo-8-quinolinyl-β-D-glucopyranoside in order to compare this system to that of clioquinol. We also synthesized, 8-quinolinyl-β-D-glucopyranoside, an 8-hydroxyquinoline glucoconjugate. The reason for the development of glucoconjugates is the glucose avidity, and the over-expression of glucose transporters in cancer cells. Here we demonstrate that glycoconjugates are cleaved in vitro by β-glucosidase and these systems exhibit antiproliferative activity against different tumor cell lines in the presence of copper(II) ions. 相似文献
63.
We show experimentally that the angular Goos-H?nchen (GH) effect can be easily observed, also without employing its resonant enhancement at Brewster incidence. An s-polarized beam was used to decouple the polarization from the propagation dynamics of the beam. We found that, in this case, the angular GH effect can be strongly enhanced by increasing the angular aperture of the Gaussian beam. Our experiments suggest a route toward observing the angular GH effect for true scalar waves, such as acoustic waves and quantum matter waves. 相似文献
64.
Anna Aiello Ernesto Fattorusso Marialuisa Menna Sanja Perovi?-Ottstadt Tobias A.M. Gulder 《Tetrahedron》2005,61(30):7266-7270
The isolation and characterization of the known pyrrole alkaloid agelongine (6) and of the new natural product daminin (7), the bromine-free analogue of 6, from a specimen of the marine sponge Axinella damicornis is described. Compound 7 showed significant neuroprotective properties. Moreover, for the supply of sufficient material for future medicinal investigations, a short total synthesis of 7 was developed. 相似文献
65.
The paper is devoted to the analysis of cracking and deformability of concrete tension members reinforced with fiber-reinforced polymer (FRP) rods. A theoretical nonlinear model, derived from a cracking analysis founded on slip and bond stresses, is adopted for evaluating the crack width, crack spacing, and elongation of tension members. The procedure takes into account the local bond-slip law, experimentally determined by means of pullout tests, and allows us to evaluate the influence of tensile stiffening. The analysis is performed with considering all parameters influencing the behavior of tension members, such as the concrete strength, the kind of FRP rebars, the surface treatment of FRP rebars, and the concrete cover thickness. The theoretical predictions are compared with available experimental results, obtained on cylindrical concrete specimens reinforced with carbon FRP (CFRP) rods, and with predictions of the traditional models usually adopted for design purposes. 相似文献
66.
Fürst JU Strekalov DV Elser D Aiello A Andersen UL Marquardt Ch Leuchs G 《Physical review letters》2010,105(26):263904
In whispering gallery mode (WGM) resonator light is guided by continuous total internal reflection along a curved surface. Fabricating such resonators from an optically nonlinear material one takes advantage of their exceptionally high quality factors and small mode volumes to achieve extremely efficient optical frequency conversion. Our analysis of the phase-matching conditions for optical parametric down-conversion (PDC) in a spherical WGM resonator shows their direct relation to the sum rules for photons' angular momenta and predicts a very low parametric oscillation threshold. We realized such an optical parametric oscillator (OPO) based on naturally phase-matched PDC in lithium niobate. We demonstrated a single-mode, strongly nondegenerate OPO with a threshold of 6.7 μW and linewidth under 10 MHz. This work demonstrates the remarkable capabilities of WGM-based OPOs. 相似文献
67.
L. Aiello D. Riccio P. Ferraro S. Grilli L. Sansone G. Coppola S. De Nicola A. Finizio 《Optics and Lasers in Engineering》2007,45(6):750-755
We present, for the first time to the best of our knowledge, a phase unwrapping method based on an algorithm which makes use of Green's first identity. This method aims at recovering the correct phase information encoded in a fringe pattern after digital holography (DH) numerical processing. DH provides a quantitative measurement of the three-dimensional surface profile of objects. The information about the profile can be obtained in principle from the phase-map. However, the measured phase-map provides the actual phase values wrapped mod.2π so that an unwrapping process is required in order to reconstruct the object profile. 相似文献
68.
The behavior of fiber reinforced plastic (FRP) concrete elements under service conditions is analyzed. Taking into account the real constitutive law of materials and local bond-slip law which adequately describes the interaction between the FRP reinforcement and concrete, a numerical procedure is proposed for obtaining moment-curvature relationships for a cracked beam element. Using the moment-curvature laws, the load-deflection analysis of FRP concrete beams is carried out. To study the influence of geometric and mechanical parameters, a numerical investigation was carried out and the results obtained were compared with those from other methods and Codes. The results of the experimental investigation are described and compared with those of the proposed procedure; the comparison shows good agreement between the theoretical and experimental results.Department of Materials Science, University of Lecce, Via per Arnesano, 73100 Lecce, Italy. Published in Mekhanika Kompozitnykh Materialov, Vol. 35, No. 2, pp. 163–172, March–April, 1999. 相似文献
69.
We report the first measurement of the spin Hall effect of light (SHEL) on an air-metal interface. The SHEL is a polarization-dependent out-of-plane shift on the reflected beam. For the case of metallic reflection with a linearly polarized incident light, both the spatial and angular variants of the shift are observed and are maximum for -45°/45° polarization, but zero for pure s and p polarization. For an incoming beam with circular polarization states however, only the spatial out-of-plane shift is present. 相似文献
70.
Federica Aiello Marcel G. Simons Jan W. van Velde Paulo Dani 《Molecules (Basel, Switzerland)》2021,26(13)
Pyrethroids are among the insecticidal compounds indicated by the World Health Organization for mitigation of vector-borne diseases. Active deltamethrin (with chiral configuration α-S,1-R-cis) is one of the most effective pyrethroids characterized by low toxicity to humans, and it is currently tested as active ingredient for insecticidal paints. Nevertheless, several degradation processes can occur and affect the insecticidal efficacy in the complex paint matrix. In the present study, a detailed NMR analysis of deltamethrin stability has been carried out under stress conditions, mimicking a water-based insecticidal paint environment. Two novel by-products, having a diastereomeric relationship, were identified and their structure was elucidated by combining NMR, HPLC, GC-MS, and ESI-MS analyses. These compounds are the result from a nucleophilic addition involving deltamethrin and one of its major degradation products, 3-phenoxybenzaldehyde. Given the known toxicity of the aldehyde, this reaction could represent a way to reduce its concentration into the matrix. On the other hand, the toxicology of these compounds towards humans should be addressed, as their presence may adversely affect the performance of deltamethrin-containing products. 相似文献