1,721,030 research outputs found
The Structure Of The Complex [ηC6H11)Ni(PPh3)2] ZnCl3 Containing A 1,1′,2-Trimethylallyl Ligand
No full textThe structure of the title complex has been determined by X-ray diffraction methods; the conformation of the trimethylallyl ligand is discussed
Ligand geometries and excited states of allene
No full textThe distorted geometries of allene found by X-ray diffraction in various transition-metal complexes are used for the excited states of this molecule in a CNDO calculation of transition energies, following a reasoning recently proposed by McWeeny, Mason and Towl. The good agreement between the allene u.-v. spectrum and the calculated values of the transition energies and the comparison with the results of a standard CNDO-CI calculation suggest that the method proposed in the present paper may be applied also to similar cases, where experimentally determined geometries can be attributed to the excited states of molecules
Crystal and molecular structure of di-mu-acetato-bis-[(2-methylallyl-3-norbornyl)palladium(II)]
No full textA three-dimensional structure analysis of the title compound has been carried out from diffractometer data by Patterson and Fourier methods. Crystals are orthorhombic, with a = 11.822, b = 12.513, c = 17.609 Å, space group Pbcn, Z = 8. The structure was refined by least squares to a final R of 0.062 for 2215 observed reflections. The molecule is dimeric, symmetry C2, with a Pd ⋯ Pd distance of 2.960(1) Å. The co-ordination geometry about each Pd ion is approximately square-pyramidal, with the vinyl end of the lateral chain of the hydrocarbon ligand being shifted from the 'normal' position in related Pd and Pt complexes. The Pd-O distances show evidence of trans-influence by the co-ordinated carbon atom of the norbornyl moiety
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
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