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141.
Debora Puglia Franco Dominici José Maria Kenny Carlo Santulli Catia Governatori Giacomo Tosti Paolo Benincasa 《Journal of Polymers and the Environment》2016,24(1):37-47
The production of bioplastics directly from wheat flour has been demonstrated to be reliable, but scarce knowledge is available on how flour characteristics may affect the performance of thermoplastic films. In this work, we first established the most suitable recipe and process for the production of extruded films and then we used eight single-cultivar wheat flours with different baking technological properties to assess how they affect the mechanical properties of thermoplastic films. The results have shown that flours from soft grain cultivars offered more rigid and deformable films than flours from hard grain cultivars. For similar hardness, the alveographic P/L ratio of the dough was inversely related to rigidity and directly related to deformability of plastic films, while the deformation energy of the dough (W) played a role only for great differences of it. The subsequent fabrication of blends between each of the flours that yielded the best film properties and polycaprolactone (PCL) at different proportions indicated that a wheat flour/PCL ratio (TWF/PCL) of 75/25 offered the most suitable films for further application. Our results are likely to be useful for improving the plasticization of flour, in that selection of wheat flours could be tailored on the properties desired for the bioplastic films. 相似文献
142.
Moreno Di Marco Thomas Brooks Annabelle Cuttelod Lincoln D.C. Fishpool Carlo Rondinini Robert J. Smith Leon Bennun Stuart H.M. Butchart Simon Ferrier Ruud P.B. Foppen Lucas Joppa Diego Juffe‐Bignoli Andrew T. Knight John F. Lamoreux Penny F. Langhammer Ian May Hugh P. Possingham Piero Visconti James E.M. Watson Stephen Woodley 《Conservation biology》2016,30(2):392-402
World governments have committed to increase the global protected areas coverage by 2020, but the effectiveness of this commitment for protecting biodiversity depends on where new protected areas are located. Threshold‐ and complementarity‐based approaches have been independently used to identify important sites for biodiversity. We brought together these approaches by performing a complementarity‐based analysis of irreplaceability in important bird and biodiversity areas (IBAs), which are sites identified using a threshold‐based approach. We determined whether irreplaceability values are higher inside than outside IBAs and whether any observed difference depends on known characteristics of the IBAs. We focused on 3 regions with comprehensive IBA inventories and bird distribution atlases: Australia, southern Africa, and Europe. Irreplaceability values were significantly higher inside than outside IBAs, although differences were much smaller in Europe than elsewhere. Higher irreplaceability values in IBAs were associated with the presence and number of restricted‐range species; number of criteria under which the site was identified; and mean geographic range size of the species for which the site was identified (trigger species). In addition, IBAs were characterized by higher irreplaceability values when using proportional species representation targets, rather than fixed targets. There were broadly comparable results when measuring irreplaceability for trigger species and when considering all bird species, which indicates a good surrogacy effect of the former. Recently, the International Union for Conservation of Nature has convened a consultation to consolidate global standards for the identification of key biodiversity areas (KBAs), building from existing approaches such as IBAs. Our results informed this consultation, and in particular a proposed irreplaceability criterion that will allow the new KBA standard to draw on the strengths of both threshold‐ and complementarity‐based approaches. 相似文献
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146.
Pedro A. Ochoa George Alexis Sagastume Gutiérrez Juan B. Cogollos Martínez Carlo Vandecasteele 《Journal of Cleaner Production》2010,18(12):1171-1176
An approach to Cleaner Production in a small factory of hydrated lime is presented. The work aims to improving fuel and limestone utilization and reducing waste production in the plant. Efforts mainly focus on the calcination stage, where around 50% of the production costs due to fuel consumption occur. To fulfill this objective, new indicators are proposed to evaluate the performance of the lime shaft kiln, in order to develop an operational control method for the calcination process. The systematic use of the developed operational control method is a powerful tool in the daily operation of a small lime factory, since it allows a more efficient calcination process with reduced environmental impact and production cost. 相似文献
147.
A positive surge results from a sudden change in flow that increases the depth. It is the unsteady flow analogy of the stationary
hydraulic jump and a geophysical application is the tidal bore. Positive surges are commonly studied using the method of characteristics
and the Saint-Venant equations. The article presents the results from new experimental investigations conducted in a large
rectangular channel. Detailed unsteady velocity measurements were performed with a high temporal resolution using acoustic
Doppler velocimetry and non-intrusive free-surface measurement devices. Several experiments were conducted with the same initial
discharge (Q = 0.060 m3/s) and six different gate openings after closure resulting in both non-breaking undular and breaking bores. The analysis
of undular surges revealed wave amplitude attenuation with increasing distance of surge propagation were in agreement with
Ippen and Kulin theory. Also, undular wave period and wave length data were relatively close to the values predicted by the
wave dispersion theory for gravity waves in intermediate water depths. 相似文献
148.
Salvador Moncada Clara Llorens Neus Moreno Fernando Rodrigo Paul Landsbergis 《Safety Science》2011,49(4):591-598
Spanish workers have been among the most exposed to psychosocial risks across the European Union.CC.OO. and ISTAS decided to establish an action plan to empower workers’ health and safety representatives to have an influence on the psychosocial risk assessment processes leading to negotiations with employers over a more democratic, fair and healthier work organization.Most important outcomes included 3600 companies which have followed a participatory process culminating with the implementation of agreed upon at source preventive measures in 40% of cases.There exists some evidence that preventive actions have increased in Spain since CC.OO.’s workers’ health and safety representatives started systematically pushing for improvements in the psychosocial work environment, however the quality of such actions is less clear.Future priorities include: first, to overcome barriers related to the interaction with external agents, especially with professional and administrative bodies. Second, to increase collaboration with scientific institutions to ensure and improve quality of both risk assessment tools and preventive actions. Third, to evaluate at the source interventions at company level with special interest in looking at the involvement of worker representatives, managers and OH professionals and the impact of their involvement on the undertaking of effective preventive actions. Fourth, increasing interaction between ISTAS and CC.OO. in order to place demands for the improvement of psychosocial working conditions more centrally in collective bargaining. Fifth, trying to increase unity of action of all Spanish workers’ unions on the subject. 相似文献
149.
This study presents an assessment, resulting from consultation with experts in steppe-bird conservation (scientists, officers and conservationists) using the Delphi method, of a broad range of agri-environmental measures (AEMs) which have been applied in agricultural areas in Spain, with particular reference to four threatened steppe bird species. The measures which experts have valued most highly relate to the maintenance of fallow land, the prohibition of agrochemicals and the suspension of certain agricultural practices when the species are nesting. Other AEMs which have frequently been mentioned as beneficial for steppe birds, including the maintenance of straw-mulched fallows and the abandonment of farmland, were rejected by the experts. The assessment showed a high degree of consensus between experts, although differences between the four studied species were detected. Delphi assessment indicated that different birds need different AEMs. In addition, expert evaluation showed that different AEMs can cause the same effect on the target species, which could generate an over-implementation of measures. Finally, we evaluated the financial implementation of the AEMs selected by the Delphi using a Special Protection Area for birds (SPA) in the Madrid region as a case study. All the hypothetical scenarios used yielded assumable costs, oscillating between 1 and 2 times the current AEMs expenditure. In conclusion, in extensive agrarian systems with already high conservation merits, the implementation of AEMS could be improved using species-specific assessments, thus avoiding over-implementation and improving the fit between costs and benefits for conservation. 相似文献
150.
Manzo Sonia Parrella Luisa Schiavo Simona Spaziani Fabio Chiavarini Salvatore Tebano Carlo De Maio Lucio Capone Stefano Siciliano Anna Valeria Armiento Giovanna 《Environmental science and pollution research international》2022,29(55):83291-83303
Environmental Science and Pollution Research - In this study we propose, a multi-step strategy of selection and characterization of long-term dataset of contaminant concentrations in different... 相似文献