20 research outputs found
IMPLEMENTATION OF GAMMA-RAY SIMULATION FOR EDUCATIONAL PURPOSES WITH AN INNOVATIVE WEB APPROACH
No full text
Uno studio preliminare per la produzione di Carbone Solare.
No full textOggigiorno il fabbisogno energetico sta crescendo ovunque ad un tasso molto elevato, e le fonti di energia rinnovabile sono l’unica possibilità per fronteggiare la fine dei combustibili fossile, del gas naturale e degli olii fino ad oggi ampiamente utilizzati, nonché i problemi di inquinamento e di salute derivanti dall’uso di queste fonti energetiche tradizionali.
L’obiettivo di questa ricerca è quello di sfruttare la pirolisi solare in virtù 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’energia 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 è 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
PROTEIN MODELS: A COMPUTATIONAL APPROACH TO FOLDING AND AGGREGATION PHENOMENA
No full textSquare lattice protein models are used to study the competition
between folding and aggregation phenomena. The problem is
approached by considering Metropolis Monte Carlo simulations of
non-isolated lattice protein models; different protein molecules
can interact each other and, in competition with folding, can
aggregate by forming dimers. The calculations take in exam the
behavior of three types of proteins: a) proteins with a very
well designed sequence (good folders); b) proteins which folding
kinetics present kinetic partitioning effects (intermediate
folders); c) small proteins with native states having the
geometry of pure secondary structure motives (like alpha helices
or beta sheets). The results show that good folders very rarely
form aggregates; on the contrary, in almost all considered cases,
intermediate folders display high tendency to form dimers.
Finally, alpha helices display a low tendency to aggregate in
comparison to that found for beta-sheets. However, also for these
systems, structural intermediates in the folding kinetics can
strongly influence the aggregation tendency
Solar Biomass Pyrolysis with the Linear Mirror II
No full textA 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
A summary on an investigation of GAGG:Ce afterglow emission in the context of future space applications within the HERMES nanosatellite mission
No full textSpace applications of GAGG:Ce scintillators: a study of afterglow emission by proton irradiation
No full textWe 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
