Ricerc@Sapienza

In this work the anisotropic model for clays SANICLAY proposed by Dafalias and Taiebat (2013) is reformulated within the framework of hyper-elastoplasticity. The model, called SANICLAY-T, is fully defined by two scalar potential functions, the free energy and the rate of dissipation. It is first presented in the triaxial space and then generalised in the multiaxial one. The model reproduces exactly the original one for the case of associate flow rule, while leads to a different outcome for non-associated flow.

In the present study the implications of a thermodynamic-based
constitutive framework on the mechanical behaviour of soils are critically
analysed. The primary advantage of this approach as compared to the traditional
hardening plasticity is that the models are guaranteed to obey the laws of
thermodynamics. Furthermore, the use of potential functions allows to introduce
some crucial ingredients of the mechanical behaviour of soils that directly affect
the shape of the yield surface and the flow rule of the model. To illustrate the

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.

With a view to characterizing the influence of the electronic structure of the Fe atom on the nature of its bond with dioxygen (O-2) in heme compounds, a study of the UV/Vis action spectra and binding energies of heme-O-2 molecules has been undertaken in the gas phase. The binding reaction of protonated ferrous heme [Fe-II-hemeH](+) with O-2 has been studied in the gas phase by determining the equilibrium of complexed [Fe-II-hemeH(O-2)](+) with uncomplexed protonated heme in an ion trap at controlled temperatures.

The role of thermodynamics in assessing the intrinsic instability of the CH3NH3PbX3 perovskites (X = Cl,Br,I) is outlined on the basis of the available experimental information. Possible decomposition/degradation pathways driven by the inherent instability of the material are considered. The decomposition to precursors CH3NH3X(s) and PbX2(s) is first analysed, pointing out the importance of both the enthalpic and the entropic factor, the latter playing a stabilizing role making the stability higher than often asserted.

The nature of the gas phase product released during the thermal decomposition of CH3NH3PbI3 (methylammonium lead iodide) to PbI2 (lead diiodide) under vacuum is discussed on the basis of thermodynamic predictions, recently published experimental results, and new experiments presented here. From the limited data currently available, the nature of the main decomposition path is not clear because, both, the process releasing HI(g) + CH3NH2(g) (1) and that leading to NH3(g) + CH3I(g) (2) were observed under different conditions.

It is shown that relativistic Ornstein-Uhlenbeck processes driven by stochastic perturbations possessing finite propagation velocity, and specifically by Poisson-Kac processes, are consistent with the known equilibrium velocity distribution of a relativistic gas (Jüttner distribution). Some observations on the boundedness of acceleration are addressed from elementary quantum principles (quantization of the action variable).