Solar Biomass Pyrolysis with the Linear Mirror II

A simple and innovative prototype for biomass pyrolysis is presented, together with some experimental results. The setup uses only the thermal solar energy provided by a system of reflecting mirrors (Linear Mirror II) to heat a selected agro-waste biomass, such as wheat straw. At the end of the pyrolysis process, solar carbon with a high energy density (around 24 - 28 MJ/kg) is produced from a biomass with an energy density of 16.9 MJ/kg. The perspectives for a future industrial application of this setup are also discussed

New detailed characterization of the residual luminescence emitted by the GAGG:Ce scintillator crystals for the HERMES Pathfinder mission

The HERMES (High Energy Rapid Modular Ensemble of Satellites) Pathfinder mission aims to develop a constellation of nanosatellites to study astronomical transient sources, such as gamma-ray bursts, in the X and soft $\gamma$ energy range, exploiting a novel inorganic scintillator. This study presents the results obtained describing, with an empirical model, the unusually intense and long-lasting residual emission of the GAGG:Ce scintillating crystal after irradiating it with high energy protons (70 MeV) and ultraviolet light ($\sim$ 300 nm). From the model so derived, the consequences of this residual luminescence for the detector performance in operational conditions has been analyzed. It was demonstrated that the current generated by the residual emission peaks at 1-2 pA, thus ascertaining the complete compatibility of this detector with the HERMES Pathfinder nanosatellites

Uno studio preliminare per la produzione di Carbone Solare.

Oggigiorno il fabbisogno energetico sta crescendo ovunque ad un tasso molto elevato, e le fonti di energia rinnovabile sono l\u2019unica possibilit\ue0 per fronteggiare la fine dei combustibili fossile, del gas naturale e degli olii fino ad oggi ampiamente utilizzati, nonch\ue9 i problemi di inquinamento e di salute derivanti dall\u2019uso di queste fonti energetiche tradizionali. L\u2019obiettivo di questa ricerca \ue8 quello di sfruttare la pirolisi solare in virt\uf9 del suo potenziale nel fornire un metodo efficiente, sostenibile e conveniente per lo sfruttamento di una fonte energetica totalmente rinnovabile, e la caratterizzazione di una tipologia innovativa di biochar ottenuti mediante pirolisi solare. Viene inoltre presentato un semplice ed innovativo prototipo per la pirolisi di biomasse assieme ad alcuni risultati sperimentali. Il prototipo consente di pirolizzare una ben precisa biomassa locale agroalimentare e di scarto utilizzando unicamente l\u2019energia termica fornita dal sole attraverso un sistema di specchi riflettenti (Linear Mirror II). Viene inoltre approfondita la caratterizzazione chimica di queste biomasse pirolizzate solarmente mediante il Linear Mirror II. Le biomasse pirolizzate solarmente hanno una struttura porosa e grafitica e la composizione chimica indica che il carbone solare prodotto \ue8 un carbone attivo ed estremamente versatile per numerose applicazioni industriali della catalisi e come ammendante in agricoltura sostenibile.Nowadays, the energy demand is growing everywhere at a very high rate, and renewable energies are considered the only possibility to face the future depletion of fossil fuels, natural gas and oils, up to now widely used, and the pollution and health problems related to the use of these traditional energy sources. Goal of this research is to exploit solar pyrolysis because of its potential to provide an efficient, environmentally acceptable, and cost-effective method for the exploitation of a totally renewable energy source, and the characterization of an innovative class of biochars derived from solar pyrolysis. A simple and innovative prototype for biomass pyrolysis is presented, together with some experimental results. The setup allows to pyrolyze a selected and local agro-waste biomass using only the thermal solar energy provided by a system of reflecting mirrors (Linear Mirror II). The chemical characterization of biomasses which were thermally treated using the Linear Mirror II without any help from other thermal auxiliary sources, is discussed in detail. Solar carbon produced has a porous (and graphitic) structure and chemical composition suggest that as activated carbon could be a very versatile material also for catalysis. Activated carbon also enhances soil fertility and allow a more sustainable use of some soils

Space applications of GAGG:Ce scintillators: a study of afterglow emission by proton irradiation

We discuss the results of a proton irradiation campaign of a GAGG:Ce (Cerium-doped Gadolinium Aluminium Gallium Garnet) scintillation crystal, carried out in the framework of the HERMES-TP/SP (High Energy Rapid Modular Ensemble of Satellites -- Technological and Scientific Pathfinder) mission. A scintillator sample was irradiated with 70 MeV protons, at levels equivalent to those expected in equatorial and sun-synchronous low-Earth orbits over orbital periods spanning 6 months to 10 years. The data we acquired are used to introduce an original model of GAGG:Ce afterglow emission. Results from this model are applied to the HERMES-TP/SP scenario, aiming at an upper-bound estimate of the detector performance degradation resulting from afterglow emission.Comment: The article front-page does now report journal submission correctly. The size of Fig. 6 has been slightly reduce