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The paper proposes a combined approach between numerical modeling and experimental measurements for the analysis of a cogeneration system based on the reaction of liquid aluminum and water steam. Scrap aluminum is used for hydrogen production and the primary one is employed as an energy carrier to transport the energy from the alumina reduction system to the site of the suggested plant. The analysis focuses on the liquid aluminum injection phase immediately downstream the nozzle. High frequency thermo-cameras are employed to qualitatively assess the thermal behaviour the liquid aluminum jet. Fast imaging techniques are used to capture the multiphase flow pattern of the liquid metal jet during the injection phase. The experimental results are used to validate a 2D multi-phase CFD approach. The computational fluid dynamics model of the injection phase is created and used to extend the measurements and deepen the understanding of the thermo-fluid dynamics behaviour of the system. In particular, the influence of different nozzles diameters and different injection pressures on the liquid aluminum jet is investigated. A modular approach is adopted for the domain subdivision in order to represent accurately all the geometrical features, while the volume of fluid approach is used to model the multi-phase flow distribution in the real geometry under actual operating conditions. Finally, a good agreement between the measurements and the calculations is found.

A new unipolar differential logic (UDL) for the large-scale integration of amorphous In-Ga-Zn-O (aIGZO) digital circuits is proposed. Only single-threshold single-gate and aIGZO thin-film transistors are required. The proposed UDL logic gates are very insensitive to transistor parameter variations (i.e., threshold voltage, mobility, off-current, and subthreshold slope), which are inherently due to large-area low-temperature fabrication processes and operating conditions. To assess the UDL effectiveness, a wide range of parameter variations is considered: and, owing to the proposed architecture up to 1.5 $\times$ 107 UDL gates that can be integrated with a yield that is greater than 90%.

Chitosan is used worldwide as a food supplement and it is normally obtained from animal exoskeleton, mainly crustaceans. Chitosan produced from animals reportedly causes allergic reactions, thus only the equivalent deriving from fungi is permitted in winemaking. The OIV has issued specific methods to identify the biological origin of chitosan but these proved to be laborious and time consuming. To evaluate whether stable isotope ratios analysis could be a quicker and more effective tool to identify chitosan from fungi and from other origins, the H, C, N and O isotopic ratios of 35 samples deriving from various biosynthetic pathways are here presented. The Kruskal-Wallis test showed that δ13C and δ18O of the bulk samples were the most significant parameters (p

The economic assessment of an integrated anaerobic digestion and gasification system for the exploitation of the residues from an urban sewage treatment plant is carried out. The obtained bio-fuels are used in a cogeneration unit to produce both electric and thermal energy. The analysis focuses on the water treatment plant of a touristic town, characterized by a highly variable number of inhabitants. Therefore, the amount of input biomass for the integrated plant results remarkably time dependent and the design accounts for the transient nature of the input. The performance of the integrated system is modelled by developing an ad-hoc dynamic library for the simulation of the energy conversion systems under the OpenModelica open source platform. The system's performance and economic assessment are modelled by means of equations and correlations that calculate the components' behaviour on a time dependent basis. The simulation demonstrates that the final wastes to landfill decrease by a 73% improving significantly the environmental impact of the plant. Furthermore, the proposed integrated system is able to produce the 25% of the electric energy required for the plant operation. Thus, the payback period of the integrated plant results to be lower than 3 years.

The paper focuses on the CFD analysis of a full-scale module of an industrial ceramic kiln under actual operating conditions. The multi-dimensional analysis includes the real geometry of a ceramic kiln module employed in the preheating and firing sections and investigates the heat transfer between the tiles and the burners’ flame as well as the many components that comprise the module. Particular attention is devoted to the simulation of the convective flow field in the upper and lower chambers and to the effects of radiation on the different materials is addressed. The assessment of the radiation contribution to the tiles temperature is paramount to the improvement of the performance of the kiln in terms of energy efficiency and fuel consumption. The CFD analysis is combined to a lumped and distributed parameter model of the entire kiln in order to simulate the module behaviour at the boundaries under actual operating conditions. Finally, the CFD simulation is employed to address the effects of the module operating conditions on the tiles’ temperature distribution in order to improve the temperature uniformity as well as to enhance the energy efficiency of the system and thus to reduce the fuel consumption.