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THE EUROPEAN PROJECT ‘COSMOS’ FOR THE INTRODUCTION OF CAMELINA (Camelina sativa L.) AND CRAMBE (Crambe abyssinica L.) IN EUROPE: EARLY OBSERVATIONS FROM FIELD TRIALS IN THE MEDITERRANEAN BASIN
No full textThe European commission funded the project COSMOS (Camelina and crambe Oil crops as Sources of Medium-chain Oils for Specialty oleochemicals) within Horizon 2020 framework program since March 2015 for 54 months. Eighteen partners joined the consortium, and their activities are divided into eight interconnected work packages (WP). The main objectives of COSMOS are to introduce the cultivation of crambe and camelina across Europe in order to get a domestic production of medium chains fatty acids to replace part of the import of palm oil. Furthermore, the full valorization of the whole biomass produced (straws, pods, seed residues after oil extraction) by the two crops is of great importance for the project in order to derive new high value products by mean of advanced chemical and/or biological conversion technologies. From the agronomical point of view, for the first time in Southern Europe, a multi-location screening trial has been set up in order to identify the best genotypes of crambe and camelina. Ten varieties of crambe and eleven of camelina were grown at the experimental farm of the University of Bologna in spring 2015. A low input management has been adopted for both species: conventional soil tillage, low fertilization ( 2 Mg ha-1 DM). Camelina, in view of its short cycle and chilling tolerance, might represent an interesting opportunity also as winter crop or inter-crop before summer crops such as maize or soybean, thus filling the gap in shortage of alternative winter crops to wheat (Triticum aestivum L.) in the Mediterranean basin
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
Evolution of microstructural and mechanical properties of lanthanum zirconate thermal barrier coatings at high temperature
No full textCeramic thermal barrier coatings (TBCs) are usually adopted to protect hot section components of aircraft and gas turbine engines from extreme temperatures and environmental attack promoted by oxygen and corrosive media. Their applications allows to increase the durability as well as to improve the efficiency and to reduce the pollution.
In this work, thick lanthanum zirconate (La2Zr2O7) TBCs were deposited by Air Plasma Spraying (APS) and characterized about their microstructure by Scanning Electron Microscopy (SEM). The coatings, composed of single pyrochlore structure, exhibited a lamellar microstructure with embedded pores, cracks and splat boundaries. High-temperature exposure ( 50 hours at 1200 and 1350 °C, in air) assisted the partial densification of this microstructure.
The mechanical properties of as-sprayed and heat treated coatings were measured at various temperatures up to 1500 °C in air by employing four-point bending tests, properly optimized for free-standing porous coatings. The elastic modulus measured at room temperature was found to be 16 GPa and changed as the temperature of testing increased. This study was also addressed to analyze the influence of sintering phenomena on the high-temperature behaviour of the same TBCs. The thermal aging caused the partial densification of the microstructure, thus increasing the elastic modulus. However, this increase was less pronounced when the coatings were tested at higher temperature. In addition the effect of densification was clearly observable in terms of deformation at break and modulus of rupture
The evolution of thermal properties such as thermal expansion coefficient and heat capacity after high-temperature exposure was also investigated.
The results demonstrated that the TBCs herein employed are promising for applications at extreme operating conditions due to enhanced capability and resistance to sintering. They can be also used in multilayered systems in order to further improve their potentiality
Microstructure, mechanical properties and thermal shock resistance of plasma sprayed nanostructured zirconia coatings
No full textNanostructured yttria stabilized zirconia (YSZ) coatings were deposited by Atmospheric Plasma Spraying (APS). X-ray diffraction (XRD) was used to investigate their phase composition, while scanning electron microscopy (SEM) was employed to examine their microstructure. The coatings showed a unique and complex microstructure composed of well-melted splats with columnar crystal structure, partially melted areas, which resembled the morphology of the powder feedstock, and equiaxed grains. Vickers microhardness of nanostructured zirconia coatings was similar to that of the conventional ones and strongly depended on the indentation load. Otherwise, a higher thermal shock resistance was found. This effect was addressed to the retention of nanostructured areas in coating microstructure and to the corresponding high porosity. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved
High-temperature mechanical behavior of plasma sprayed lanthanum zirconate coatings
No full textRare-earth zirconates are potential materials for thermal bather coatings. Their properties are not still well known, due to any lacks in processing and characterization techniques. To this purpose lanthanum zirconate coatings were herein manufactured by plasma spraying. The coatings exhibited high porosity, due to the presence of pores, splat boundaries and microcracks. The high-temperature evolution of mechanical properties was investigated by arranging specific bending tests up to 1500 degrees C using SiC testing assembly which allows to reconstruct and measure the sample curvature and the deformation. At higher temperatures the coatings showed an inelastic behavior, related to their unique microstructure, as well as a toughening effect. (c) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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