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Dielectric and anelastic spectroscopies are complementary techniques and their combination allows valuable information to be obtained in the field of multifunctional materials. Whereas the dielectric spectroscopy measures the dielectric susceptibility ?(?,T) and it is sensitive to fluctuations of electric dipoles, the anelastic spectroscopy measures the elastic compliance or elastic susceptibility s(?,T) and it is sensitive to fluctuations of elastic dipoles. Both susceptibilities are complex, their immaginary part being due to the delayed response of the mobile defects coupled to the electric field/stress. The great advantage of using a combination of both techniques is that the anelastic measurements are insensitive to free charges, therefore it is possible to measure the dynamics of ions also in the presence of free charges. Two main types of investigations have been pursued by the combination of these techniques: the study of structural phase transitions and the study of microscopic mechanisms associated with the presence of defects, both important for the knowledge and development of multifunctional materials. We have applied this approach for different functional materials with perovskite framework: multiferroic, ferroelectric and relaxor ferroelectric ceramics, and organic-inorganic perovskite photovoltaics. Thanks to the combination of the two spectroscopies, it has been possible to probe more accurately the structural transitions involving the antiferrodisortive tilt modes of the octahedra in PZT [1] and NBT-BT [2]. It was also possible to evidence incipient phase separation in lead titanate-based multiferroics [3]. Moreover, since the elastic response is insensitive to free charges, it has been used to probe the piezoelectric response even in unpoled ceramics [4] and for the study of coexisting ferroelectric and metallic states [5]. The combination of the two techniques allowed also new features to be revealed on the reorientation dynamics of the organic molecules in MAPbI3 photovoltaic organic-inorganic perovskites and the hindrance of their ferroelectric order by coupling with the tilt modes [6]. 1. F. Cordero, F. Trequattrini, F. Craciun, C. Galassi, Phys. Rev. B, 87 (2013) 094108 2. F. Cordero, F. Craciun, F. Trequattrini, et al., Phys. Rev. B, 81 (2010) 144124 3. F. Craciun, F. Cordero, B. Vasile, et al., Phys. Chem. Chem. Phys., 20 (2018) 14652 4. F. Cordero, F. Craciun, F. Trequattrini, C. Galassi, Phys. Rev. B, 93 (2016) 174111 5. F. Cordero, F. Trequattrini, F. Craciun, et al., Phys. Rev. B, 99 (2019) 064106 6. F. Cordero, F. Craciun, F. Trequattrini, et al., J. Phys. Chem. Lett., 9 (2018) 4401

Dolomite-based binders are characterised by interesting technical and environmental features. For their synthesis, sources of both CaO and MgO are required. The idea developed in this work is to couple the synthesis of dolomite-based binders, starting from a natural dolomite, through the concept of concentrated solar energy (needed to drive the endothermal dolomite calcination process) in fluidised bed reactors. To this end, a fluidised bed system, where the concentrated solar radiation is mimicked by the use of Xe-lamps (short-arc), has been set up and operated. Natural dolomite (sieved in the 420-590 ?m size range) was calcined at a nominal temperature of 850 °C, and bed temperature profiles during solar-driven calcination were investigated. Then, four binders were prepared by mixing slaked dolomite (obtained from the hydration of solar calcined dolomite) with either blast furnace slag or coal fly ash as supplementary cementitious materials. The binders were hydrated for curing times ranging from 7 to 56 days. X-ray fluorescence, X-ray diffraction and combined differential thermal and thermogravimetric analyses were employed as characterisation techniques both to analyse the chemical composition of starting materials and to investigate the evolution of the hydration in the four systems.

The effect of external EGR on knock was evaluated using a CFR engine. Combustion pressure was sampled on a time basis. A band pass filter in the time domain was applied to the pressure cycles. Five knock indices were calculated for each combustion cycle. The problem to quantify knock intensity was focused. At this extent, measurements were carried out on standard iso-octane-n-heptane blends in the test conditions used for the determ of the Motor Method Octane Number (MON). Knock intensity was varied acting on compression ratio. For each index, the conditions of absence of knock were determined using motored cycles. The indices were compared and one of them, showing the lowest C.O.V., was selected for further measurements. The effect of EGR on test fuels having different composition was evaluated varying the compression ratio, at fixed ignition timing. In this way, the same level of detonation, obtained in the absence of EGR, was realized with different amounts of external EGR. Percent variation of compression ratio was used to compare the ability of fuels, having different octane number, to tolerate compression ratio increase in presence of EGR. In particular, the tests were carried out on a matrix of twelve fuels with three levels of EGR. The results show that with all tested fuels the percent increase of compression ratio is strongly dependent on EGR.

In the present work, an experimental study on a lab-scale adsorption refrigerator, based on activated carbon/ethanol working pair is reported. An extensive testing campaign has been carried out at the CNR ITAE laboratory, with multiple aims. First, the performance has been evaluated in terms of both COP and Specific Cooling Power (SCP), under different boundary conditions, including both air conditioning and refrigeration applications. Attractive SCPs, up to 180 W/kg and 70 W/kg for air conditioning and refrigeration, respectively, were measured. Under the same conditions, COP between 0.17 and 0.08 were obtained. In addition, different management strategies, namely, heat recovery between adsorbers and re-allocation of phase durations, were evaluated to identify their influence on the system. Both strategies confirmed the possibility of increasing COP and SCP up to 40% and 25%, respectively. Moreover, a design analysis based on the experimental results has been carried out, to suggest possible improvements of the system. The obtained results demonstrated the possibility of employing a non-toxic refrigerant like ethanol reaching performance comparable with other harmful refrigerants like ammonia and methanol.

In recent years, the portable technology is receiving a great interest and significant improvement due to the progresses in electronic technology development and energy storage solutions. The decrease in power requirements for working energy systems, due to the increased efficiency and to the reduction in components size, opens the access to new solutions for power supplying. In particular, alternative backup systems for battery charging or replacement could be designed taking advantage of unconventional technologies. It is the case of small photovoltaic portable panels or fuel cells technology: in these solutions different sources are used to produce limited electrical powers required to keep devices on. In this paper, a thermoelectric solution for the power generation has been considered: the generator has been designed and assembled starting from a catalytic combustor. Catalytic combustion allows safe control of the processes, and the choice of a hydrocarbon fuel ensures the power availability and a fast recharge. The size of the system is set to fit a volume close to the one of AA batteries. The electrical power output obtained is close to 1 W with a cold side temperature below 40 °C. The limited values of these physical parameters allow obtaining a portable and safe device. The generator has been fully characterized in different ranges of fuel flow rates and the performances have been thoroughly analysed for processes optimization and efficiency improvement.

(Abstract) This paper proposes a new power line communication (PLC) architecture for monitoring and remote control of Distributed Generators (DG) and Energy Storage Systems (ESS) connected to low voltage distribution networks. The final aim is to improve the performance of the PLC link in terms of robustness and efficiency in devices addressing. The proposed solution is based on a concentrator, to be installed in secondary substation, and a new PLC bridge, to be linked both to inverters and interface protection systems of DGs or ESSs. In this way, a communication link is obtained between distribution system operator (DSO) and DG or ESS owners. The proposed system is able to provide advanced functions for the remote control of DGs and ESSs inverters, not only in terms of remote disconnection but also in terms of adjusting the inverter operating modes.

AbstractClimate change effects along with anthropogenic activities present the main factors that threaten the existence of heritage sites across the north Nile Delta of Egypt close to the coastline of the Mediterranean Sea. Observing the changes in the landscape close to the archaeological sites is an important issue for decision‐makers in terms of reducing the negative impact of natural events and human activities. The coastal heritage sites are becoming strongly threatened by the rising sea level phenomena that will happen due to global warming. Focusing on the distribution of the archaeological sites, this study aims to detect the areas at risk of shoreline erosion or accretion in the northern shoreline of the Nile Delta. In this study, the changes in the northern shoreline of the Nile Delta were observed and calculated during the last hundred years based on the integration between the old topographic maps from surveys in 1900, 1925 and 1945, optical satellite images captured by Landsat in 1972, 1986 and 2000; Sentinel2 2021; and the Radar SRTM data. The results of this study showed that the changes were enormous with a great shoreline erosion process over the last 121 years recorded along the shoreline in the periods between 1900–1925, 1925–1945, 1945–1972, 1972–1986, 1986–2000 and 2000–2021. The areas eroded were about 5.3, 4.7, 5.6, 8.9, 2.5 and 5.4 km2, respectively. Such negative movements caused the loss of two heritage sites, and the expected changes will lead to the loss of additional heritage sites in the next 500 years. Furthermore, a model was suggested for protecting the coastal heritage sites threatened by the risk of submergence. This study can help the decision‐makers to detect the coastal archaeological sites at risk and create innovative solutions for protecting these irreplaceable heritage sites.

AbstractThe potential impacts of future climate scenarios on water balance and flow regime are presented and discussed for a temporary river system in southern Italy. Different climate projections for the future (2030–2059) and the recent conditions (1980–2009) were investigated. A hydrological model (Soil and Water Assessment Tool) was used to simulate water balance at the basin scale and streamflow in a number of river sections under various climate change scenarios, based on different combinations of global and regional models (global circulation models and regional climate models). The impact on water balance components was quantified at the basin and subbasin levels as deviation from the baseline (1980–2009), and the flow regime alteration under changing climate was estimated using a number of hydrological indicators. An increase in mean temperature for all months between 0.5–2.4 °C and a reduction in precipitation (by 4–7%) was predicted for the future. As a consequence, a decline of blue water (7–18%) and total water yield (11–28%) was estimated. Although the river type classification remains unvaried, the flow regime distinctly moves towards drier conditions and the divergence from the current status increases in future scenarios, especially for those reaches classified as I‐D (ie, intermittent‐dry) and E (ephemeral). Hydrological indicators showed a decrease in both high flow and low flow magnitudes for various time durations, an extension of the dry season and an exacerbation of extreme low flow conditions. A reduction of snowfall in the mountainous part of the basin and an increase in potential evapotranspiration was also estimated (4–4.4%). Finally, the paper analyses the implications of the climate change for river ecosystems and for River Basin Management Planning. The defined quantitative estimates of water balance alteration could support the identification of priorities that should be addressed in upcoming years to set water‐saving actions.