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Classification of P,N-binucleating ligands for hetero- and homobimetallic complexes
No full textThis review focuses on P,N-ligands capable of establishing binucleating interactions and on the resulting bimetallic complexes.
The work is grouped by the type of P,N-binucleating ligand backbones which are closely responsible for the chemistry of their correspondent bimetallic complexes. The P,N-binucleating ligands are classified according to their length (the number of atoms between the N- and P-donor), their backbone structure (the relative disposition of the N- and P-donor), and the presence or not of additional donor atoms.
Similarities between the structures of the bimetallic complexes obtained with P,N-ligands inside each group are highlighted. Based on the analysis of the different groups, the structure of new metallo/P,N-ligand complexes not yet synthesized can be hypothesized. A summary of the few examples of P,N-binucleating ligand based bimetallic complexes that have catalytic activity is given
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
A New Polycatenated 3D Array of Interlaced 2D Brickwall Layers and 1D Molecular Ladders in [Mn2(bix)3(NO3)4] ·2CHCl3 [bix = 1,4-bis(imidazol-1-ylmethyl)benzene] That Undergoes Supramolecular Isomerization upon Guest Removal
No full textThe reactions of Mn(II) nitrate with the flexible ligand 1,4-bis(imidazol-1-ylmethyl)benzene (bix) (reagent ratios 1:2–1:3)
yield novel interesting coordination networks including, besides the ladder-like species [Mn(bix)1.5(NO3)2] and the 2-fold interpenetrated
three-dimensional (3D) cds network [Mn(bix)2(NO3)2], the exceptional [Mn2(bix)3(NO3)4] · 2CHCl3, which is comprised of two different
supramolecular isomers, namely, brickwall layers and one-dimensional (1D) molecular ladders, polycatenated to give a 3D (2D + 1D)
architecture
Metal-organic coordination frameworks assembled with the long flexible ligand 4,4 '-bis(imidazol-1-ylmethyl)biphenyl
No full textNine novel coordination polymers have been obtained from the self-assembly reactions of the flexible ligand 4,4 '-bis( imidazol-1-ylmethyl) biphenyl (bimb) with different metal salts and their structures and supramolecular architectures have been characterized by single crystal X-ray analysis. Three of them contain 1D polymers, namely [Cd(bimb)(OTs)2(H2O)2] (3), [Cd(bimb)2(H2O)2](OTs)2.4MeOH (4) and [Cu(bimb)2(H2O)2](SO4).2H2O.2(acetone) (7), consisting of single-stranded chains (3) or ribbons of rings (4 and 7) that are joined via H-bond bridges to give layers of (4,4) topology (sql). Three polymeric products contain 2D frameworks, i.e. the two nitrate species [Cd(bimb)2(NO3)2] (2) and [Cu(bimb)2(NO3)2] (8), that are isostructural and contain flat sql layers, and [Zn2(bimb)3(SO4)2].(bimb).Solv (9), comprised of interdigitated (6,3) honeycomb-like (hcb) layers threaded by the free bimb ligands. Also three 3D networks have been isolated, namely [Cd(bimb)(H2O)(SO4)].Solv (1), containing 1D Cd(bimb) undulated single chains that are cross-linked by bridging sulfate anions and water molecules to give an overall 3D array with the diamond topology (dia), [Co(bimb)2(SO4)] (5) that consists of ribbons of rings spanning two distinct directions of propagation bridged by the sulfate anions to generate a 3D single net with the CdSO4 type topology (cds), and [Co2(bimb)5(H2O)2](NO3)4.4EtOH.2H2O (6), the first case of a 3D network assembled exclusively with the use of the bimb spacer, that contains ribbons and single chains cross-linked to give an overall 3D single cds array. Three forms of the uncoordinated ligand, i.e. bimb, bimb.H2O and [bimbH](PF6), were also isolated and structurally characterized to obtain a more complete information about the conformations of the bimb molecule
Variations on the Author
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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