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FT-IR spectroscopic and calorimetric characterization of the adsorbed forms of water on a-Fe2O3 obtained by thermal decomposition of a-FeOOH
No full textMicrocalorimetric and FT-IR spectroscopic study of benzene adsorption on α-Fe2O3 and γ-Al2O3
No full textThe adsorption of benzene at room temperature on α-Fe2O3 and on γ-Al2O3 powders was investigated by heat-flow microcalorimetry and FT-IR spectroscopy. On iron oxide a chemisorption-combustion step is followed by a highly exothermic adsorption step, reversible at r.t. Few combustion centres exist on alumina if reducing pretreatment is not carried out. Two reversible adsorption steps are subsequently observed and were interpreted as due to interaction with two different types of surface hydroxy groups. © 1984 Wiley Heyden Ltd., Chichester and Akadémiai Kiadó, Budapest
Microcalorimetric and FT-IR spectroscopic study of the adsorption of methanol on TiO2 (anatase)
No full textThe adsorption of methanol on TiO2 (anatase) activated under vacuum at different temperatures has been studied by adsorption microcalorimetry and FT-IR spectroscopy. Both dissociative and undissociative chemisorption of methanol molecules have been found corresponding to the evolution of very high adsorption heats (qdiff > 150 kJ mol-1). At higher coverages, hydrogen bonded and dimeric adsorbed species are formed corresponding to differential adsorption heats of 50-120 kJ mol-1. © 1985
Infrared spectroscopic study of micronised geothite
No full textInfrared spectra of micronised goethite between 4000 cm-1 and 20 cm-1 were studied. Stretching and bending vibrations of structural hydroxy-groups were assigned using data on deuterated samples and comparison with α-Fe2O3 obtained by thermal decomposition. The existence of two different kinds of surface hydroxyls was also confirmed and an interpretation of their nature proposed. Various measured low-frequency bands were assigned to vibrations of the structural FeO6 blocks. © 1978
Adsorption of methanol on alumina in the 298-473 K temperature range: a microcalorimetric and FT-IR spectroscopic study
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
Anthropological survey on north Cameroon peopling: I. GC subtyping (with a brief overview on the GC distribution in sub-Saharan Africa).
No full textGroup-specific component (GC) polymorphism was investigated in 1324 subjects belonging to 12 ethnic groups from North Cameroon including Daba, Fali, Fulbe, Kanuri, Mada, Mafa, Mandara, Mundang, Uldeme, Podokwo, Tali, and Tupuri. The GC*1F frequency ranged from 0.785 among Fulbe to 0.847 among Mundang, that of GC*1S from 0.071 among Mafa to 0.125 among Fulbe and that of GC*2 from 0.035 among Uldeme to 0.092 among Tupuri. The results obtained are discussed in the light of the knowledge about the distribution and the possible selective relevance of GC polymorphism
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