Publications by authors named "A Freni"

Ionic liquids (ILs) represent promising working fluids to be used in thermal energy storage (TES) technologies thanks to their peculiar properties, such as low volatility, high chemical stability, and high heat capacity. Here, we studied the thermal stability of the IL N-butyl-N-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate ([BmPyrr]FAP), a potential working fluid for TES applications. The IL was heated at 200 °C for up to 168 h either in the absence or in contact with steel, copper, and brass plates to simulate the conditions used in TES plants.

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Background: There is limited information on the effect of the connection between subcrestally placed implants and abutments on marginal bone levels. The aim of the present retrospective study was to evaluate marginal bone levels after definitive prosthesis delivery around implants with an internal 5° conical connection placed in a subcrestal position.

Materials And Methods: Patients treated with fixed prostheses supported by implants placed at a subcrestal level between 2012 and 2018 were recalled for a follow-up examination.

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The organic linker in a metal organic framework (MOF) affects its adsorption behavior and performance, and its structure and dynamics play a role in the modulation of the adsorption properties. In this work, the combination of H nuclear magnetic resonance (NMR) longitudinal relaxometry and theoretical calculations allowed details of the structure and dynamics of the organic linker in the NH-MIL-125 MOF to be obtained. In particular, fast field cycling (FFC) NMR, applied here for the first time on MOFs, was used to disclose the dynamics of the amino group and its electronic environment through the analysis of the N quadrupole relaxation peaks, observed in the frequency interval 0.

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This work investigates the application of novel sorption materials to heat-powered desalination systems. Two ionic liquids 1-ethyl-3-methylimidazolium acetate (Emim-Ac) and 1-ethyl-3-methylimidazolium methanesulfonate (Emim-Oms) were impregnated in two silica supports, namely, Syloid AL-1FP and Syloid 72FP. Emim-Ac and Emim-Oms composite sorbents have been compared on morphology, water vapor sorption equilibrium, and heat of sorption.

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This paper shows that it is possible to exploit the modulated metasurface concept to control the unwanted coupling between antennas that are installed on the same satellite. The metasurface is combined with a Multi-Layer thermal Insulation blanket to reduce its specular reflection by spreading the energy incoherently in the surrounding space. In the design, sub-wavelength radiating elements printed on thin substrate have been used to make the metasurface response azimuthally independent, and to keep the weight of blanket down.

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