1,721,304 research outputs found
Synthesis, Structure and Dynamics of a C2-symmetrical Bis(oxazolinylmethylene)pyrrolinato-Zinc Complex
No full textReaction of 2,5-bis(eyanomethyl)pyrrole with L-valinol in presence of zinc trifluoromethansulfonate and subsequent workup with aqueous NaCl gave the corresponding zinc complex 2, in which the double bonds of the pyrrole ring isomerize to give rise to a conjugated chromophore. Its molecular structure displays tetrahedral distortion from planarity, as was established by a single crystal structure analysis. The non-planarity of 2 gives rise to a dynamic behaviour in solution with the chlorido-ligand swinging through the plane spanned by the three N-donor functions
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
Bisoxazolines with one and two sidearms: stereodirecting ligands for copper-catalysed asymmetric allylic oxidations of alkenes
No full textA series of sidearm functionalized bisoxazoline ligands has been synthesized by reaction of the monolithiated methyl{bis(oxazolinyl)} methane with the appropriate electrophiles, and tested in the copper catalyzed asymmetric allylic oxidation of cyclohexene ("Kharasch - Sosnovski" reaction). The observed enantioselectivities were higher ( up to 85% ee) than for the unfunctionalized bisoxazoline ("BOX") derivatives (ca. 60% ee). Regardless of the functional groups incorporated into the sidearm unit, the ee's obtained for the different derivatives were essentially indistinguishable. This implies that the sidearms do not interfere directly in this reaction and only play an indirect role by virtue of their steric demand. Three of the copper complexes have been characterized by X-ray diffraction, establishing a distorted octahedral coordination geometry around the copper atom in all three cases. In the elongated distorted CuN2O4 octahedra, the two nitrogen atoms of the oxazolines and one oxygen atom of each acetate ligand occupy the 'equatorial' positions whereas the sidearms do not interact with the metal centres
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
CCDC 988044: Experimental Crystal Structure Determination
No full textRelated Article: Aneliia Shchyrba, Susanne C. Martens, Christian Wäckerlin, Manfred Matena, Toni Ivas, Hubert Wadepohl, Meike Stöhr, Thomas A. Jung, Lutz H. Gade|2014|Chem.Commun.|50|7628|doi:10.1039/C4CC02463J,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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
- …
