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Hybrid nanostructures with switchable and reversible “blue-red-green” emission were efficiently synthesized. These nanostructures comprise polyhedral oligomeric silsesquioxanes (POSS) that behave as a nanocage that can be functionalized with terpyridine-based organic ligands, which can be easily complexed with europium (III) ions. The complexes were characterized by UV-Vis and fluorescence spectroscopy and their stoichiometry was also confirmed by H NMR spectroscopy. In the presence of the Eu(III) ions, the octafunctionalized nanocages self-assemble to form 3D architectures that display an intense red-emission, especially in the solid state. The presence of an alkenyl group bridging the inorganic core to the organic moiety was employed to tune the emission properties by trans-cis isomerization of the double bond. In the case of the octafunctionalized nanocages (O-POSS), this isomerization was monitored in the presence of Eu(III) cations and was accompanied by an evident colour change from blue (trans-O-POSS) to red (Eu@trans-O-POSS) and finally to green (cis-O-POSS) as consequence of the release of the metal cations. This behaviour, together with the easy dispersion of the dry powder and the possibility of coating as a film in presence of small amounts of solvent, makes the emissive solid promising for applications in materials science.

In the framework of MORFEO project, financed by the Italian Space Agency (ASI), a study is currently under way to estimate and validate monitoring technologies of deformations with SAR data, to the implementation of a pre-operational service supporting the Civil Protection Department in landslide risk monitoring. The study on ground deformations is performed in MORFEO by applying two different technologies: SBAS developed by CNR-IREA in Naples and SPINUA developed by Politecnico of Bari. These technologies work with SAR data in C band and the use of X band data acquired by COSMO/SKY-MED is under trial. In particular the present report describes the generation and validation activities of EO SAR products (Synthetic Aperture Radar) obtained in landslide areas in Lombardia and Umbria by using ascending and descending passages of ENVISAT satellite. The results obtained in Umbria highlight the presence of deformation phenomena in the area corresponding to the landslide region in Ivancich (Assisi). A general accordance between GPS and SAR sets results by the comparison. In Lombardia GPS deformation time sets have been estimated for SAR data validation. This has highlighted the potential and limits of SAR interferometric techniques for landslide monitoring in an alpine context. Moreover, a first multi-temporal interferometric analysis in X band has been carried out through the SPINUA algorithm. Preliminary results over the area of GARZENO (COMO) show that even with a limited number of COSMO/SkyMED images, there is a good agreement with linear displacement rate maps estimated in C-band. An accurate investigation shall be feasible as soon as a consistent number of COSMO/SkyMED acquisitions is available (not less than 25-30).

In the present work we present first results of ground deformation measurements inferred through repeat-pass Synthetic Aperture Radar (SAR) Interferometry (InSAR) in C- and X-band over an Italian Alpine area, in Lombardia region. The activity was carried out in the framework of the MORFEO (MOnitoraggio e Rischio da Frana mediante dati EO) project founded by the Italian Spatial Agency (ASI) and dedicated to landslide risk assessment. A number of areas affected by hydrogeological instabilities have been selected and studied in detail by processing both C- and X-band SAR data through SPINUA, a Persistent Scatterer like algorithm. In particular, two stacks of 30 Ascending ENVISAT SAR images (October 2004 - January 2009) and 32 Descending ENVISAT SAR images (December 2004 - January 2009) have been independently processed to ensures the detection of movements occurring along both west and east facing slopes. Moreover, further deformation measurements have been obtained by processing a set of 12 COSMO-SkyMED ascending HIMAGE interferometric acquisitions (Satellite CSKS1; Beam HI-03; POL: HH; Incidence Angle: 29°) provided by ASI. After a proper tuning of the interferometric algorithmic solutions, even with very high normal baselines, we are able to appreciate the potentials of X-band interferometry. Although the number of COSMO-SkyMED acquisitions is quite limited, spanning a period of only 10 months (August 2008 - June 2009), SPINUA was capable to retrieve preliminary ground displacement patterns that are in good agreement with those previously estimated in C-band. Quite impressive is to realize that, because of the tenfold improved resolution of X-band images, multi-temporal InSAR techniques may be successfully applied for the estimation of the displacement maps with a number of acquisitions much lower than in C-band. InSAR-derived displacements provided on areas of hydrogeological interest are going to be validated in the framework of MORFEO project by the geological pa