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Thermally stable doped and undoped porous aluminium oxides and nanocomposite CeO2-ZrO2 and Al2O3 containing mixed oxides
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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
Preliminary Acoustic tests on resilient materials: comparison between common layers and nano-structured layers
No full textNowadays, efficient thermal insulation is a principal requirement for buildings and, accordingly, huge amounts of in-sulators are applied in the constructions, particularly for external walls, radiant floor, roofs, etc. Acoustic insulation is another of the most stringent parameters to be taken into account both in the construction of new buildings or their re-juvenation in order to obtain good internal comfort. Notwithstanding these needs, only few materials are marketed which feature reasonably good both thermal and acoustic insulation properties. More often, materials with good sound insulation proprieties show poor thermal efficiency and vice versa. Further, most of materials which have good both acoustic and thermal properties are thicker than either acoustic or thermals insulators which creates technical difficulties in their use, particularly in the buildings’ renovation. Nano-structured materials such as, for example, microporous or aerogel materials, are characterised by highly efficient thermal insulation power, in spite of their reduced thickness compared to conventional systems
PREPARATION AND CHARACTERIZATION OF LANBO4 FROM AMORPHOUS PRECURSORS
No full textAmorphous precursors of LaNbO4 have been prepared by coprecipitation and mechanical alloying. Powder characteristics before and after calcination were studied by thermogravimetric analysis, differential thermal analysis, Fourier transform-infrared spectroscopy and X-ray diffraction, and the crystallographic changes during thermal treatment were documented by high-temperature X-ray diffraction. The tetragonal structure was stabilized at room temperature for the mechanically alloyed product; cells dimensions were determined from the X-ray diffraction patterns and volume change between monoclinic and tetragonal phase was evaluated and is 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
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