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101.
Riccardo Di Corato Philomena Piacenza Mariarosaria Musarò Raffaella Buonsanti Pantaleo Davide Cozzoli Massimo Zambianchi Giovanna Barbarella Roberto Cingolani Liberato Manna Teresa Pellegrino 《Macromolecular bioscience》2009,9(10):952-958
Nanostructures displaying fluorescence and magnetic properties at the same time are potentially useful for achieving simultaneous bio‐separation and bio‐sensing (e.g., magnetic separation coupled with multiplexing optical detection of different tumour cell populations). Spherical nanobeads that display both fluorescent and magnetic features are reported; they are fabricated by grafting fluorescent oligothiophene molecules to an amphiphilic polymer that is then used to enwrap iron oxide nanoparticles, which acts as the magnetic domain. By tuning experimental conditions, control over the number of magnetic nanoparticles per bead and over the bead diameter (30–400 nm) was achieved. A cell separation efficiency of the level required for cell sorting applications is also reported.
102.
Stefanelli M Pomarico G Tortora L Nardis S Fronczek FR McCandless GT Smith KM Manowong M Fang Y Chen P Kadish KM Rosa A Ricciardi G Paolesse R 《Inorganic chemistry》2012,51(12):6928-6942
Functionalization of the β-pyrrolic positions of the corrole macrocycle with -NO(2) groups is limited at present to metallocorrolates due to the instability exhibited by corrole free bases under oxidizing conditions. A careful choice of the oxidant can limit the transformation of corroles into decomposition products or isocorrole species, preserving the corrole aromaticity, and thus allowing the insertion of nitro groups onto the corrole framework. Here we report results obtained by reacting 5,10,15-tritolylcorrole (TTCorrH(3)) with the AgNO(2)/NaNO(2) system, to give mono- and dinitrocorrole derivatives when stoichiometry is carefully controlled. Reactions were found to be regioselective, affording the 3-NO(2)TTCorrH(3) and 3,17-(NO(2))(2)TTCorrH(3) isomers as the main products in the case of mono- and disubstitution, in 53 and 20% yields, respectively. In both cases, traces of other mono- and disubstituted isomers were detected, which were structurally characterized by X-ray crystallography. The influence of the β-nitro substituents on the corrole properties is studied in detail by UV-visible, electrochemical, and spectroelectrochemical characterization of these functionalized corroles. Density functional theory (DFT) and time-dependent DFT (TDDFT) calculations of the ground and excited state properties of these β-nitrocorrole derivatives also afforded significant information, closely matching the experimental observations. It is found that the β-NO(2) substituents conjugate with the π-aromatic system of the macrocycle, which initiates significant changes in both the spectroscopic and redox properties of the so functionalized corroles. This effect is more pronounced when the nitro group is introduced at the 2-position, because in this case the conjugation is, for steric reasons, more efficient than in the 3-nitro isomer. 相似文献
103.
Rachele Pucciariello Vincenzo Villani Sandra Belviso Giuliana Gorrasi Mariarosaria Tortora Vittoria Vittoria 《Journal of Polymer Science.Polymer Physics》2004,42(7):1321-1332
The thermal behavior and overall isothermal crystallization kinetics of a series of organophilic modified montmorillonite–poly(?‐caprolactone) nanocomposites were investigated. In general, the thermal behavior was influenced more by the type of dispersion than by the clay content. For nanocomposites in which silicate platelets were predominantly dispersed in the polymer matrix to give exfoliated structures, the thermal properties were improved with respect to those of neat poly(?‐caprolactone), whereas in those cases in which simply intercalated structures were attained, the thermal properties regularly decayed as the clay content increased. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1321–1332, 2004 相似文献
104.
D.G. Fong M. Heller A.M. Shapiro M. Widgoff D. Bogert M. Johnson C.-Y. Chien P. Lucas A. Pevsner R.A. Zdanis R.A. Burnstein C. Fu D.V. Petersen R.M. Robertson H.A. Rubin R.D. Sard A.E. Snyder J. Tortora H. Taft 《Physics letters. [Part B]》1974,53(3):290-296
Results are reported based on a study of π?p interactions at 147 GeV/c in the FERMILAB 30-inch Proportional Wire Hybrid Bubble Chamber System. We have measured the topological cross sections and separated two-prong elastic and inelastic channels. In addition, we have extracted leading particle cross sections using the increased momentum resolution of the downstream proportional wire chambers. We have compared our results with experiments and predictions of a simple fragmentation hyphothesis. 相似文献
105.
D. Fong M. Heller A.M. Shapiro M. Widgoff F. Bruyant D. Bogert M. Johnson R. Burnstein C. Fu D. Petersen M. Robertson H. Rubin R. Sard A. Snyder J. Tortora D. Alyea C.-Y. Chien P. Lucas H.D. Taft 《Nuclear Physics B》1976,102(3):386-404
The results presented in this paper were obtained from a 105 000 frame exposure of the FNAL Hybrid Proportional Wire Chamber-30 inch Bubble Chamber System, in a tagged beam of 147 GeV/c negative particles. Elastic, total and topological cross sections were obtained for both π?p and K?p interactions. Comparisons with other data, taken with various beam particles over large momentum intervals, show good agreement with KNO scaling, and similarity in the scaling behavior of σn for the different beam particles. 相似文献
106.
107.
This paper reviews our previous studies on the diffusion behavior in polymers clay nanocomposites. A geometric model for predicting the effective diffusivity through this type of systems as a function of clay sheets orientation, volume fraction, polymer clay interaction, and aspect ratio is proposed. Model predictions are compared to the effective diffusivity generated using random walk simulations as well as with predictions obtained from already existing theoretical models. Fair agreement is found between the model prediction and the results of numerical simulations. With respect to the already existing theoretical models, the present mathematical derivation seems more adequate to describe diffusion behavior in conventional nanocomposites systems (i.e. when fillers present very low values of volume to surface ratio). Experimental diffusion tests are discussed and interpreted with the aid of the proposed model. In addition to the aspect ratio and clay concentration, the polymer clay interactions as well as the sheets orientation are the factors controlling the barrier properties of polymer‐layered silicate nanocomposites. Good agreement was found in the case of samples containing exfoliated clay, whereas the model fails in the case of micro‐composites, in which the inorganic lamellae are agglomerated in clusters. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 265–274, 2006 相似文献
108.
Clemenza Massimiliano Bonesini Maurizio Carpinelli Massimo Cremonesi Oliviero Fiorini Ettore Gorini Giuseppe Hillier Adrian Ishida Katsu Menegolli Alessandro Mocchiutti Emiliano Oliva Piernicola Prata Marco Rendeli Marco Rignanese Luigi Pio Rossella Massimo Sipala Valeria Soldani Mattia Tortora Ludovico Vacchi Andrea Vallazza Erik 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(3):1357-1363
Journal of Radioanalytical and Nuclear Chemistry - The implementation in the RIKEN-RAL negative muons facility of a new muon beamline monitoring and novel digital data acquisition system for gamma... 相似文献
109.
Giovanna Guidoboni Marcello Guidorzi Mariarosaria Padula 《Journal of Mathematical Fluid Mechanics》2012,14(1):1-32
We prove a continuous dependence theorem for weak solutions of equations governing a fluid–structure interaction problem in
two spatial dimensions. The proof is based on a priori estimates which, in particular, convey uniqueness of weak solutions. The estimates are obtained using Eulerian coordinates,
without remapping the problem into a fixed domain. 相似文献
110.
A new approach to energy theory in the stability of fluid motion 总被引:5,自引:0,他引:5
Giovanni P. Galdi Mariarosaria Padula 《Archive for Rational Mechanics and Analysis》1990,110(3):187-286