Hydrothermal carbonization of pure cellulose and birchwood samples was carried out at temperatures between 160 and 280 °C, 0.5 h residence time and biomass-to-water ratio of 20 wt% dry basis, to investigate HTC reactivity of cellulose naturally occurring lignocellulosic biomass. Pure cellulose samples remained unaltered at temperatures up to 220 °C, but significantly decomposed at 230 °C producing a thermal recalcitrant aromatic, high energy-dense material, showing lignin-like behavior. Fourier Transform Infrared spectroscopy (FTIR) showed dehydration and aromatization reactions occurring at temperatures equal or higher than 230 °C for pure cellulose samples while similar increase in aromatization for birchwood hydrochars was evident only at temperatures equal or higher than 260 °C. Acid hydrolysis, Thermogravimetric analysis (TGA) and FTIR suggest that a higher thermal resistance of natural occurring cellulose in birchwood (when compared to pure cellulose sample) could be related to a 'protecting shield' offered by interlinked lignin in the plant matrix.

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The finding of the bla(IMP-22) gene in P. fluorescens environmental strains and P. aeruginosa clinical isolate suggests the ongoing spread of bla(MBL) genes in several bacterial species and in different environments.

Abstract:Complex systems of water distribution networks (WDS) are used to supply water to users. WDSs are systems where a lot of distributed energy is available. Historically, this energy is artificially dissipated by pressure reduction valves (PRVs), thanks to which water utilities manage the pressure level in selected nodes of the network. The present study explores the use of economic hydraulic machines, pumps as turbines (PATs) to produce energy in a small network located in a town close to Palermo (Italy). The main idea is to avoid dissipation in favor of renewable energy production. The proposed study is applied to a WDN typical of the Mediterranean countries, where the users, to collect water during the period of water scarcity conditions, install private tanks. The presence of private tanks deeply modifies the network from its designed condition. In the proposed analysis, the economic benefit of PATs application in water distribution networks has been investigated, accounting for the presence of users' private tanks. The analysis, carried out by mean of a mathematical model able to dynamically simulate the water distribution network with PATs, shows the advantage of their installation in terms of renewable energy recovery, even though the energy production of PATs is strictly conditioned by their installation position.

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