1,720,972 research outputs found
Fabrication of dense and porous biphasic calcium phosphates: Effect of dispersion on sinterability and microstructural development
No full textL’innovazione tecnologica dei materiali al servizio del progetto: focus sull'Architettura italiana del secondo Novecento
No full textA review on aqueous gelcasting: A versatile and low-toxic technique to shape ceramics
Full text linkThis review aims to provide a comprehensive survey of recent low-toxic approaches used in the gelcasting process. In recent years, several natural gelling agents have been developed as possible alternatives to acrylamide systems, which were previously used extensively but are now rarely employed owing to their neurotoxicity.
This work collects some successful case studies on aqueous gelcasting based on low-toxic or non-toxic gel-formers that have been applied to produce both dense and porous ceramics. Major innovations in the development of nanocomposite materials, transparent ceramics and microstructurally graded materials are discussed as well
Preparation and characterization of Ce-ZrO2/Al2O3 composites by DLP-based stereolithography
Full text linkThis work investigates the printability of Ce-ZrO2/Al2O3 composites through a Digital Light Processing (DLP) technology. Commercially available 10 mol% CeO2 and 12 mol% CeO2-stabilized zirconia were mixed with alumina powders, to provide 11 mol% CeO2-stabilized ZrO2/16 vol% Al2O3 (Ce-ZA16) composite materials. The powders were dispersed under wet conditions, and the homogeneous nanometric dispersion was maintained once added into the liquid monomer. Slurries at several solid loadings were explored, with and without dispersant addition. First, the key role of the dispersant to significantly enhance the solid loading and thus the sintered density was demonstrated. Second, among different dispersant-added slurries at various solid loadings, ranging from 65 to 80 wt%, the best compromise between rheological behavior and curing depth was estab-lished. The best formulations, comprised between 70 and 80 wt%, successfully provided fully dense and completely homogeneous composites
An investigation of the beneficial effects of adding carbon nanotubes to standard injection grout
Full text linkMortar grouting is often used in masonry constructions to mitigate structural decay and repair damage by filling cracks and voids, resulting in an improvement in mechanical properties. This paper presents an original experimental investigation on grout with added carbon nanotubes (CNTs). The samples were prepared with different percentages of CNTs, up to 1.2 wt% with respect to the binder, and underwent three‐point bending tests in crack mouth opening displacement mode and compressive tests. The results showed that very small additions (up to 0.12 wt% of CNTs) increased not only flexural and compressive strengths (+73% and 35%, respectively, in comparison with plain mortar) but also fracture energy (+80%). These results can be explained on the basis of a reduction in porosity, as evidenced by mercury intrusion porosimetry, as well as by a crack bridging mechanism and by the probable formation of nucleation sites for hydration products, as observed through scanning electron microscopy
Novel calcium phosphate/PCL graded samples: Design and development in view of biomedical applications
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
- …
