1,720,991 research outputs found
L'importanza della raccolta per le colture da biomassa
No full textStandardizzare la materia prima per le colture da biomassa adatte alla combustione diretta è fondamentale per permettere la nascita di una filiera produttiva. La raccolta riveste un ruolo fondamentale per il completamento di questa filiera, sono state eseguite perciò delle prove di raccolta di colture erbacee da biomassa quali il sorgo da fibra , l'arundo ed il panico con la finalità di imballare il prodotto, essiccato in campo, per facilitarne la conservazione ed il trasporto
EFFECTS OF GEOMETRICAL PARAMETERS OF WOOD PELLET ON MASS FLOW RATE IN A HOPPER-AUGER PROTOTYPAL ANALYTIC INSTRUMENT
No full textThe last decade has been characterized by the growth of demand of wooden pellet. This has led consumers and producers to an increase in attention towards pellets quality. Among pellets quality parameters, geometrical ones such as length and diameter, are hardly considered by industry operators. Nevertheless, pellet length is particularly important since it affects how this form of biofuel fills the available spaces,impacting on biofuel feeding capacity, namely the mass flow rate (MFR). Currently, technical standard ISO 17225-2 does not consider MFR as a key parameter for the assessment of biofuels quality. Nevertheless, the authorsbelieve that paying more attention to geometrical parameters and their influence on MFR could translate into an increase in energy efficiency.Preliminary resultsallowed to assess an inverse relation between the average length of samples and MFR.In particular, it has been obtained a 15% difference in MFR between samples with higher and lower average length values
ASSESSMENT OF TREATED WOOD RESIDUES AS FUELS FOR MICRO AND SMALL SCALE CHP SYSTEMS
No full textResidual biomass typically includes lignocellulosic materials generated by the agricultural, forest, and agro-industrial sectors. It has been estimated that only in Italy approximately 22 million tons of residual biomass are produced per year. The sustainable use of lignocellulosic biomass and the development of low-emission generation technologies such as micro and small-scale combined heat and power (CHP) systems can be highly advantageous to achieve a rapid transition towards decarbonization of the electricity sector. The choice of the CHP system highly depends on the availability and chemical-physical characteristics of the type of biomass used as fuel. Consequently, this study assesses the thermal behaviour and the chemical-physical characteristics of treated wood residues (MDF, OSB, Chipboard, etc.) to determine their potential use as fuels in micro and small scale CHP systems
Mechanical harvesting line setting of giant reeds
No full textThis study evaluated the possibility of adopting haymaking farming machinery in giant reed (Arundo donax L.) harvesting. The test shows the technical and energy aspects of mechanical harvesting using only one specific machine, a shredding machine, designed and developed by an Italian constructor for large biomass herbaceous crops (giant reed, sorghums, switchgrass, Mischantus, etc). It is designed for high vegetative growth crops, as it is able to spread products over all soil surfaces or, alternatively, carry out windrowing. Tests were conducted in the south of Italy (Campania region) on the experimental farm Torre Lama in Bellizzi (SA). Biomass was shredded, dried in the field, and baled for use in a logistic chain and storage. The first step was the cutting and shredding of biomass crops with the specific shredder rear-mounted in an agricultural tractor. The biomass then was dried on the field, constantly monitored for moisture content, and finally, baled with a trailed round baler for storage (second step) and used in a specific logistic chain. The test showed good performance of the shredder machine between 1.17 and 1.77 ha h-1 with an operative speed between 3.9 and 5. 9 km h-1. To define the hourly production, a high wet production level of 60.70 t ha-1 and a low level of 56 t ha-1 were used as references. Under the climatic conditions of the experimental test, this harvesting system showed some advantages, such as the possibility of immediate and long-term biomass storage (less than 14% moisture content), the potential alternative use of the biomass, and the reduced resource use compared to that of other ordinary crops growing in the area
Beet Sowing Seed Production: Environmental and Economic Aspects in Irrigation System – Some Insights
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
THE USE OF MICRO NEAR-INFRARED SPECTROSCOPY AND PRINCIPAL COMPONENT ANALYSIS (PCA) TO DETERMINE ORIGIN AND SOURCE OF WOOD PELLET
No full textQualitative properties of woody biofuel need to be declared due to their great influence on the combustion process. The furnace performance and the environmental impact could be improved with major monitoring of the physical and chemical characteristics of incoming biofuel. Furthermore, raw components origin should be tracked in the whole supply chain, promoting traceability. The lack of a unique characterization system could be overtaken with the Near Infrared (NIR) spectroscopy application as a cheaper, faster, and no-invasive tool to investigate main wood components and origin discrimination based on spectral differences. So, a portable NIRScan Nano has been applied to evaluate the separation between grounded softwood and hardwood but also a virgin and treated wood sample. Chemometric analysis of PCA has been carried out and the main results have been shown considering the score and loading plot of the pre-treated spectra. A rough separation between virgin and treated wood was obtained, mainly related to natural heterogeneity and the presence of discriminant chemical components. Similar results have been confirmed considering the variability between softwood and hardwood. According to the separation trends between each group, NIR proves to be an affordable and intuitive method to assess qualitative features of woody biofuel
- …
