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81.
Elisa Campioli Cédric Rouxel Marco Campanini Lucia Nasi Mireille Blanchard‐Desce Francesca Terenziani 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(11):1982-1988
Fully organic core–shell nanoparticles that promote luminescence spatial confinement and enhancement at the core–shell nanointerface are designed and prepared. These molecular‐based bicomponent nanostructures give rise to very efficient directional excitation energy transfer from the shell to acceptor molecules in the core located at the core–shell nanointerface. A striking luminescence enhancement is observed with respect to the corresponding single‐component nanoparticles, which is ascribed to large local electric fields generated at the nanointerface between the polarizable molecular core and shell. 相似文献
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Simona Maggini Elisa CappellettoFabrizio Girardi Wilma VaonaRosa Di Maggio 《Progress in Organic Coatings》2013
Silica based cellulose nanocomposites obtained from (3-mercaptopropyl)trimethoxysilane or vinyltrimethoxysilane and 3-butynoate-substituted zirconium-oxoclusters were prepared and their surface morphology, wettability, and thermo-mechanical properties were studied. The composites showed a hydrophobic surface, high strength, and resistance to thermal degradation and aging; in comparison to the untreated paper they required a higher temperature to activate combustion and generated less heat during all thermal processes. 相似文献
84.
Fl��via Santos Twardowski Pinto Simone Hickmann Fl?res Carolina Elisa Schneider Marco Antonio Z��chia Ayub Plinho Francisco Hertz 《Food and Bioprocess Technology》2011,4(4):559-565
In this work, the influence of oxygen mass transfer rates on the production of cyclodextrin glycosyltransferase (CGTase) by
the alkaliphilic bacterium Bacillus circulans ATCC 21783 was investigated. Experimental design and response surface methodology were applied to optimize agitation speed
and air flow rate in batch cultivations, in order to identify their significant effects and interactions with the synthesis
of CGTase. Results were expressed as the volumetric mass transfer rates of oxygen (kla, [per hour]). The maximal CGTase productivity of 155 U mL−1 h−1 was achieved with kla of 48 h−1. CGTase production was also studied in fed-batch cultures using the optimized parameters obtained in the batch experiments.
The maximal CGTase productivity on fed-batch cultivations was 137 U mL−1 h−1 with feeding rates of starch at 0.17 g L−1 h−1. 相似文献
85.
The problem of the characterisation of ancient mortars and plasters for restoration purposes is discussed and a methodology is proposed starting from the physical separation of the binder from aggregates. The procedure was applied to the plasters of the Ducal Palace in Mantua [Mantova] (Cavallerizza courtyard, XVI cent.): the results show the suitability of the proposed methodology for the determination of the plasters' nature, microstructure and even original formulation. 相似文献
86.
Francisco Prieto Manuela Rueda José Hidalgo Elisa Martínez Inmaculada Navarro 《Electrochimica acta》2011,(23):7916
The kinetics of azobenzene reduction on mercury electrodes in the absence of diffussional mass transport is studied by electrochemical impedance spectroscopy (EIS) in acetic acid/acetate buffered solutions at different pH values. Cyclic voltammetry experiments confirm the absence of diffusion effects and provide the values of the surface equilibrium potential. The analysis of the impedance frequency spectrums at every potential within the faradaic region conforms well the model and provides the global rate constant of the process, kf. The potential dependence of kf suggests the existence of an EE mechanism, with two electron transfers controlling the overall rate. The kinetic parameters of every step are obtained and their pH dependences clarify the role played by the protonation steps. 相似文献
87.
Ciaramelli Elisa; Rosenbaum R. Shayna; Solcz Stephanie; Levine Brian; Moscovitch Morris 《Canadian Metallurgical Quarterly》2010,36(3):619
The ability to navigate in a familiar environment depends on both an intact mental representation of allocentric spatial information and the integrity of systems supporting complementary egocentric representations. Although the hippocampus has been implicated in learning new allocentric spatial information, converging evidence suggests that the posterior parietal cortex (PPC) might support egocentric representations. To date, however, few studies have examined long-standing egocentric representations of environments learned long ago. Here we tested 7 patients with focal lesions in PPC and 12 normal controls in remote spatial memory tasks, including 2 tasks reportedly reliant on allocentric representations (distance and proximity judgments) and 2 tasks reportedly reliant on egocentric representations (landmark sequencing and route navigation; see Rosenbaum, Ziegler, Winocur, Grady, & Moscovitch, 2004). Patients were unimpaired in distance and proximity judgments. In contrast, they all failed in route navigation, and left-lesioned patients also showed marginally impaired performance in landmark sequencing. Patients' subjective experience associated with navigation was impoverished and disembodied compared with that of the controls. These results suggest that PPC is crucial for accessing remote spatial memories within an egocentric reference frame that enables both navigation and reexperiencing. Additionally, PPC was found to be necessary to implement specific aspects of allocentric navigation with high demands on spontaneous retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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89.
Since the XIV century the Pio Palace in Carpi (MO, Italy) has been subjected to many additions and rearrangements and, in the last decades, to wide restoration works. Nevertheless the XVII century main portal has not been restored yet, due to its complex and peculiar surface alteration forms in comparison with the other parts of the building, and still suffers a deep decay and degradation by complex chemical-physical processes. 相似文献
90.