1,720,981 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
Waste-minimized synthesis of C2 functionalized quinolines exploiting iron-catalysed C-H activation
Herein we present an efficient and regioselective iron-catalyzed methodology for the external oxidant-free functionalization of quinoline-N-oxides. The protocol, based on the use of inexpensive and easily accessible FeSO4, showed broad applicability to a wide range of substrates. An additional green feature of this synthetic methodology is H2O being the only by-product. Experimental and computational investigations provide support to a mechanism based on a facile C-H activation event. The green efficiency of the process has also been carefully assessed using: (i) metrics related to the synthetic process (AE, Yield, 1/SF, MRP and RME); (ii) safety/hazard metrics (SHZI and SHI); and (iii) metrics related to the metal used as the catalyst (Abundance, OEL and ADP). In addition to the many advantages of this protocol related to the green iron catalyst used and the safety/hazard features of the process, an E-factor value of ca. 0.92 (84 to >99% reduction compared to known protocols) evidently confirms the sustainable efficiency of the procedure presented. Practical utility has also been demonstrated by performing the reaction efficiently on a multi-gram scale. This journal i
ERP indexes of functional differences in brain activation during proper and common names retrieval
ERP indexes of functional differences in brain activation during proper and common names retrieval.
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