1,721,178 research outputs found
Valutazione di un prototipo per la raccolta di colture da biomassa a destinazione energetica
No full textIn Italia settentrionale le principali colture individuate per la produzione di biomassa sono il sorgo da fibra (Sorghum bicolor) fra quelle annuali, la canna comune (Arundo donax) e il panico (Panicum virgatum) per le colture poliennali. Uno degli aspetti di maggiore criticità nella coltivazione di tali piante è rappresentato dalla raccolta che evidenzia alcune problematicità riconducibili sia alla elevata taglia e sezione del fusto delle colture che richiede l’impiego di macchine specifiche sia ai costi di intervento.
La ricerca è stata finalizzata allo sviluppo di un prototipo in grado di trinciare sfibrare e andanare la biomassa di colture poliennali per consentirne la raccolta in un secondo passaggio con rotoimballatrice. La macchina realizzata, impiegata su coltura di Arundo e panico, ha evidenziato una buona capacità di lavoro e il prodotto ottenuto ha presentato caratteristiche dimensionali e umidità compatibili con la termovalorizzazione diretta
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
Valutazione del comportamento delle alfa feto-proteine e degli acidi grassi nel liquido amniotico di gravidanze normali e patologiche per la diagnosi di maturità polmonare fetale.
No full textPellet production from residual biomass of greenery maintenance in a small-scale company to improve sustainability
Full text linkReplacing fossil energy sources with renewable energy sources is a key strategic action to limit environmental issues. To achieve this goal, substitution with biomass is beneficial due to its versatility in various fields. In terms of circular economy and sustainability, the possibility of energy exploitation of residual biomass is particularly desirable in small-medium enterprises. The use of supply chain by-products can improve sustainability and create opportunities for companies. The purpose of this study is to evaluate the suitability of residual biomass of conifers and broad-leaved trees to produce quality pellets using an agri-pellet machine activated by the power take-off of a tractor. This system can be employed at the farm level. Wood biomass of four species was tested; poplar, stone pine, black locust, and oak. Wood chips samples were analyzed to determine their qualitative characteristics following the technical standard ISO 17225-4. Based on the results, different wood blends were created to produce pellets, subsequently characterized according to ISO 17225-2. The analyses carried out on wood chips and pellets were bulk density, moisture, ash content, calorific value, elemental composition, chlorine, sulfur, and heavy metals. In addition, particles size was measured only for wood chips, while the length, diameter, mechanical durability, and ash melting behaviors were determined only for pellets. Some of the analyzed mixtures show acceptable values according to the current ISO technical standards. The values related to the apparent pellet bulk density and the durability test highlight that not all the mixtures are suitable to produce quality pellets. Results also represent a good starting point for future studies
Evaluation of cradle to gate environmental impact of frozen green bean production by means of life cycle assessment
No full textThe main objective of this study is to assess the impact of frozen green bean production and processing. The analysis and relative information collected regards a medium industry located in the south of Marche region (Italy) and the whole production system, from field to industry, is in a range of about 100 km between Marche and Abruzzo regions. The aim of this study is to assess the impact of 1 kg of frozen green bean for two different cultivation protocols for herbicides and pesticides application in order to assess the possible advantages due to shifting to different field treatments. The baseline scenario (A) considers the application of two herbicides (Pendimethalin and Linuron) and two pesticides (Altacor and Azoxystrobin), the alternative scenario (B) considers one herbicides application (Clomazone) and two pesticides (Emamectine and Azoxystrobin).
The analysis has been conducted following ISO 14040 and 14044 on Life Cycle Assessment (LCA) and Product Category Rules for arable crops v. 2.0. LCI (Life Cycle Inventory) and LCIA (Life Cycle Impact Assessment) phase have been performed using LCA software SimaPro® v. 8.2.3.0 with updated databases. The most used databases for this study are Ecoinvent 3 and Agri-footprint, LCI data have been collected through interviews, consulting official documents and company management programs. The system boundaries considered includes crop production, transport to industry plant and industry processing and all the data are referred to 2014 crop season. Crop production LCI considers seeds, fertilizers, pesticides, field activities, yield and relative emissions. Transportations covers distances and payload with empty return. Industry phase considers transformation efficiency, energy, fuels, water. The function of the production chain is to provide frozen green bean, no coproduct or by-product were produced. Residues and product losses from industry processing are managed by anaerobic digestion as waste. Plastics and other wastes from field and industry has been treated by landfill. Data regarding field phase were collected by interviews and consulting official management documents from 43 farms. Data regarding industrial phase have been gathered from automated management systems hardware/software AS/400 (IBM).
The LCIA results for 1 kg of frozen green been show an impact of about 0.7 kg of CO2 eq for GWP, 1.9E-4 kg of C2H4 eq kg for PCOP, 3.5E-3 kg of SO2 eq for AP and 1.7E-3 kg of PO43- for EP. The analysis conducted comparing two different solutions of plant protection and herbicides application shows how solution A has a lower impact on ADP, ADP fossil, GWP 100yr, ODP, MEP, PCOP, AP and EP from 0.04% to 11% about. On the other hand, solution B has a lower impact on HTP, FEP, MEP and TEP between 4 and 40%.
The analysis conducted shows the impact of frozen green been at industry level representative of medium size processing plant with average technology. The only information available in literature are limited to open field production impact assessment of raw green bean without any kind of industry transformation. . Simply replacing herbicide treatment and one pesticide application, for preventing weed and pest resistance, there is a consistent reduction of impact on different categories for ecotoxicity group without increasing too much the impact on other categories considered. The only exception can be found for ADP category in which the impact of alternative scenario (B) is higher than baseline (A). The reason lies in the lower active ingredient concentration and higher amount of commercial product used for solution B. From the analysis remains evident the contribution on ADP fossil, GWP and ODP due to energy used in industrial phase. On the other side field phase contributes more on ADP, HTP, FEP, AP and EP
Concentrazioni plasmatiche di estriolo totale e ormone lattogeno placentare durante il trattamento con Ampicillina.
No full textVariations 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
Optimized selectivity in CO2 electrochemical reduction using amorphous CuNi catalysts: insights from density functional theory and machine learning simulations
No full textAmorphous materials represent a promising platform for advancing CO2 electrochemical reduction due to their inherently diverse coordination environments. In this study, we demonstrate computationally the superior performance of amorphous CuNi alloys for CO2 electrochemical reduction. By integrating machine learning forcefields for efficient structure generation and density functional theory for subsequent structural refinement and property calculations, we reveal the potential of these disordered systems to outperform their crystalline counterparts. Machine learning forcefields can generate a bulk structure containing a mixture of Cu and Ni atoms, resulting in enhanced catalytic performance. Effective screening of the amorphous surfaces is used to identify undercoordinated Cu and Ni sites in the amorphous structure to synergistically promote selective CO production and favor ethanol formation over ethylene via the stabilization of the *COCHO intermediate, resulting in significantly lower Gibbs free energy changes compared to the crystalline counterpart. The varying atomic coordination environments on amorphous surfaces promote both C–C bond formation and subsequent proton-electron transfer, leading to ethanol formation. These findings demonstrate the superior catalytic performance of amorphous CuNi, highlighting its potential for efficient and selective electroreduction of CO2
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