Ricerc@Sapienza

In the CoViD-19 pandemic, the precautionary approach suggests that all possible measures should be established and implemented to avoid contagion, including through aerosols. For indoor spaces, the virulence of SARS-CoV-2 could be mitigated not only via air changes, but also by heating, ventilation, and air conditioning (HVAC) systems maintaining thermodynamic conditions possibly adverse to the virus. However, data available in literature on virus survival were never treated aiming to this.

The effect of humidity on the climatic conditions and the turbulence around an isolated building has not been yet investigated in literature. This paper analyses the simultaneous effect of architectural and environmental parameters on the vortex creation around a building, focusing on the impact of relative humidity. Sixty-four 3D computational fluid dynamics simulations have been performed, coupling 4 values of inlet velocity, air temperature, solar radiation and building height with 4 values of relative humidity.

CsPbBr3 perovskite is highly desired to fabricate many optoelectronic devices: high photovoltage solar cells, tandem solar cells, light-emitting diodes, lasers, photodetectors, field effect transistors etc. However, to realize these applications the resistance to humidity, one of the most important stressing agents, needs to be understood. In this article, we investigate the effect of prolonged exposure (up to 500h) of CsPbBr3 to ~60% and 80% relative humidity by in-situ X-ray diffraction and ex-situ scanning electron microscopy and UV-visible spectroscopy.

In this work, a noninvasive microwave-based system for monitoring water content in stone materials used in Cultural Heritage structures is presented. By placing a planar resonator in front of the considered stone sample, trough reflection scattering parameter measurements, it is possible to associate the resonant frequency of the resonator to the moisture content of the stone sample. In this way, an experimental relationship between resonant frequency and moisture content can be obtained.

In this paper, preliminary results of complex permittivity measurements of clay-brick material will be presented. The general aim of the experimental project is to correlate the measured permittivity of construction materials with the content of water and salt, in order to obtain information on the condition of ancient walls by using non-invasive techniques. The complex permittivity values reported in this paper have been obtained by waveguide measurements on samples of clay-brick dried and then immersed in demineralized water or in a saturated solution of demineralized water and NaCl.