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IMPLEMENTATION OF GAMMA-RAY SIMULATION FOR EDUCATIONAL PURPOSES WITH AN INNOVATIVE WEB APPROACH
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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
Get PDFA 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
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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