Original vegetation recovery of two degraded areas in the Mediterranean island of Marettimo.

Fake news e post verità nella società dell'algoritmo

The essay has as its object fake news and excess of pieces of information with particular attention to the pandemic emergency we are currently living: Covid‐19. After a careful consideration about what fake news actually are, the paper analyzes the pitfalls concerning the communication through virtual technologies, where social networks let the news reach the user only if they pass some requirements, in order to give the user a personalized experience of being informed. As a result, the profiling process traps the user in a cage, which is a paradox, because the internet it’s literally supposed to be without borders and barriers. The current crisis caused by the global pandemic has brought t…

Photoinduced charge separation in functional carbon-silver nanohybrids

In recent times, nanoscience is devoting growing interest to the easy assembly of well-established nanomaterials into hybrid nanostructures displaying new emerging features. Here, we study the photophysicochemical response of binary nanohybrids obtained by the spontaneous coupling of luminescent carbon dots to silver nanoparticles with controlled surface charge. Evidence of the successful coupling is obtained by steady-state and time resolved optical measurements and further confirmed by direct imaging. We demonstrate strong interactions within nanohybrids, which can be modelled in terms of a sub-picosecond electron transfer from photoexcited carbon dots to silver nanoparticles. Accordingly…

Effects of solarization and biofumigation on tomato greenhouse production in the southern coast of Sicily

Photocycle of point defects in highly- and weakly-germanium doped silica revealed by transient absorption measurements with femtosecond tunable pump.

AbstractWe report pump-probe transient absorption measurements addressing the photocycle of the Germanium lone pair center (GLPC) point defect with an unprecedented time resolution. The GLPC is a model point defect with a simple and well-understood electronic structure, highly relevant for several applications. Therefore, a full explanation of its photocycle is fundamental to understand the relaxation mechanisms of such molecular-like systems in solid state. The experiment, carried out exciting the sample resonantly with the ultraviolet (UV) GLPC absorption band peaked at 5.1 eV, gave us the possibility to follow the defect excitation-relaxation dynamics from the femto-picosecond to the nan…

EFFECTS OF SOLARIZATION AND BIOFUMIGATION ON TOMATO GREENHOUSE PRODUCTION IN THE SOUTHERN COAST OF SICILY

The photophysics of distorted nanographenes: Ultra-slow relaxation dynamics, memory effects, and delayed fluorescence

The controlled deformation and engineering of the sp2 carbon network in atomically-precise nanographenes, and their substantially larger size as compared to typical optical dyes, opens new opportunities for the modulation of optical and electronic properties, but the peculiar photophysics of these systems is still poorly understood. Here, through a detailed comparative study of two well-defined distorted nanographenes, we show that they can exhibit interesting photophysical features, such as triplet-triplet annihilation delayed fluorescence, ultra-slow excited state dynamics, and excitation-wavelength memory effects on the nanosecond and sub-nanosecond relaxation cascades. Some of these beh…