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Climate change projections for the last 30 years of the 21st century, for boreal summer precipitation in tropical America, have been made by developing a statistical downscaling (SD) model applied to the SLP outputs of 20 GCMs of CMIP5, for present climate (1970–2000), and for future (2071–2100) under the RCP2.6, RCP4.5 and RCP8.5 scenarios. For present climate, many SD GCMs faithfully reproduce the precipitation field in many regions of the study area. For future climate, as the radiative forcing increases, the projected changes intensify and the regions affected expand, with higher coherence between models. The zone between central and southeastern Brazil registered the most pronounced precipitation changes by a large number of SD models, even for the RCP2.6. Except for this region in Brazil, in general, the changes in rainfall range from moderate (± 25%) to intense (from ±70% to ±100%) as the radiative forcing increases from the RCP2.6−RCP8.5. For this latter scenario, all SD models present significant precipitation changes for more than 50% of the area, in some cases reaching 75% of area with significant changes. For the ensemble mean, the results show three extensive regions with significant changes under the three scenarios, the most highlighted changes being for the RCP8.5: a northwest-southeast band that extends from northern Mexico to eastern Brazil, crossing through northern Colombia, along with the regions in the south of the study area, with generally moderate precipitation increases; and a band that extends from eastern Ecuador to southeastern Brazil, with major decreasing changes. This pattern of change could be related with a possible strengthening in frequency in terms of La Niña events for the end of the century.

For the first time, nanocrystalline Eu2O3thin films, exhibiting ?50% of porous volume, highly accessible mesoporosity, pore diameter of about 10 nm, and thermal stability up to 830?°C, were prepared using the evaporation-induced self-assembly (EISA) process from europium (III) chloride and specific polyethylene oxide based copolymer structuring agent. Crystallization of the inorganic network was achieved through a controlled thermal treatment sequence that was followed by in situtime-resolved SAXS/WAXS analysis involving synchrotron radiation. Atomic force microscopy (AFM) and x-ray diffraction (XRD) were used to complete the characterization of the crystallization of the film. Porous structures were additionally analysed by transmission electron microscopy (TEM), and environmental ellipsometry porosimetry (EEP), while the composition of the films was characterized by Rutherford back-scattering (RBS). Finally, the luminescence properties of these layers were investigated. [ABSTRACT FROM AUTHOR]