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The influence of solids loading and particle shape on the green microstructure of slip‐cast bodies was investigated. Three commercial silicon carbide (SiC) powders (two coarse varieties with the same particle‐size distribution (PSD) but different particle shapes and a finer powder) were used to prepare bimodal PSDs designed to maximize the packing density. Various surface‐active agents (anionic, cationic, and non‐ionic) were tested. Anionic dispersants were the most effective in dispersing aqueous SiC slurries. The effectiveness of dispersants was evaluated by sedimentation tests using very dilute slurries, by rheology, and by the packing density of slip‐cast bodies prepared from suspensions loaded with 62.5 wt% solids, stabilized with a fixed amount of dispersant (0.25 wt%, relative to the solids). Then, the best dispersant was selected to study the effects of dispersant and solids concentrations on the degree of packing of bimodal suspensions that contained the sharper‐edged coarse particles. It could be observed that the green density was dependent on both parameters, initially showing an increase to a maximum, followed by a decreasing trend. A high value of 74.5% of the theoretical density (TD) was obtained from suspensions that contained 70 wt% solids and 0.1 wt% dispersant. The substitution of the angular coarse particles by similarly sized but more spherical particles resulted in an additional increase in green density to >76 wt% TD. The results can be interpreted in terms of freedom of particles upon deposition on the cast layer, which enables particle rearrangement, and segregation phenomena.

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European agricultural activity plays an important role in European and world food security through the agricultural production, supply and international trade. The main aim of this paper was analyses the agricultural sustainability of the twenty-nine Member States of the European Union in terms of economics, environmental, social and political activity. Information and data comes from FADN database from the European Commission. The methodology includes the min-max approach and multivariate methods, namely, Component Principal Analysis and Cluster analysis. The results confirm three groups of European countries, namely, the North and Central countries; the New Member States and the Mediterranean counties. The results also confirm that European agriculture firms and respective countries had a medium sustainability. The main conclusion highlines confirms the importance of the sustainability as a tool to better adjust agricultural policies among the European Member States.

P P è è r r e e s s 7 7 5 5 0 0 0 0 7 7 P P a a r r i i s s " "T Tr ra an ns sf fo or rm ma at ti io on ns s e ex xp pe er ri ie en nc ce ed d b by y h hi ig gh he er r e ed du uc ca at ti io on n a an nd d r re es se ea ar rc ch h i in ns st ti it tu ut ti io on ns s i in n E Eu ur ro op pe ea an n c co ou un nt tr ri ie es s" " AbstractThe Portuguese higher education system is undergoing periodic quality assessments of its teaching and research activities. Nevertheless, there is not yet an overall institutional assessment mechanism leading to a careful analysis of each institution as an organisation.Based, on one hand, upon an exploratory empirical study aiming at better understanding these institutions, in particular their strategic and quality management and innovation practices and tools, and, on the other hand, upon the study of several quality assessment models developed both for higher education institutions and business organisations, a self-assessment model was developed for the Portuguese higher education institutions. This model comprises nine criteria, each of them clearly defined, as well as the areas to address within each of them. The proposed model intends to provide a management and assessment tool, supporting self-assessment (including the identification of strong points and areas for improvement), and providing an instrument for quality improvement.In order to empirically validate the model, two different approaches were used -a qualitative and a quantitative one -the model being applied to a set of Portuguese higher education institutions, to a particular university and to a single organic unit of that same university.The quantitative approach allowed for the test and validation of the relationships between the model's different criteria. The model's underlying structure was validated through a questionnaire aimed at assessing how each Portuguese higher education institution (and the particular higher education institution considered) is dealing with a series of practices and factors considered critical for its quality improvement. A detailed statistical analysis was performed over the data collected to validate the proposed self-evaluation model structure and the relationships among its 9 underlying criteria. The analysis was made using structural equation modelling (with PLS estimation techniques).The qualitative approach was applied to the single organic unit, to verify to what extent potential users would be able to understand the model (its dimensions, how it works, how to interpret its key results), while simultaneously getting a preliminary idea of its usefulness to drive improvement in the Portuguese higher education institutions. CIPES and Universidade de Aveiro 2From the results obtained it is possible to conclude that the model can be successfully applied to higher education institutions, as a self-assessment tool to support their continuous quality improvement efforts.