1,734,427 research outputs found
"Third Generation"-Type Functional Tris(2-pyridyl)borate Ligands and their Transition-Metal Complexes
No full textPhenyltris(2-pyridyl)borates (Tpyb) are a promising class of tripodal “scorpionate”-type ligands with potential utility in the development of transition metal complexes with interesting optical, electronic or magnetic properties, and as building blocks to metallosupramolecular polymers. We report here a new class of “third generation”-type Tpyb ligands that contain different functional groups attached to the boron-bound aryl moiety. The synthesis, characterization and metal ion complexation behavior of ligands with iodo and trimethylsilyl groups is discussed. The electrochemical and absorption characteristics of the corresponding low-spin Fe(II) and Ru(II) complexes are compared. We demonstrate the further elaboration of the iodo derivatives with alkynes via Sonogashira-Hagihara coupling, a process that proceeds with high yield for the Fe(II) and Ru(II) complexes, but not for the free ligand. The borylation of the silyl-substituted Ru(II) complex with BBr3 was also investigated. In addition to the expected borylation product, Ru(Tpyb-Bpin)2, the replacement of one (major product) or two phenyl groups is observed, suggesting that electrophilic borylation occurs at both the C(Ph)-Si and the C(Ph)-B aromatic carbons. The successful attachment of a range of different functional groups at the periphery of the Tpyb metal complexes is expected to provide opportunities to access new polymeric materials via C-C coupling or click-type reactions.Peer reviewe
Surviving global warming: why eliminating greenhouse gases isn't enough/ Roger A. Sedjo.
No full textIncludes bibliographical references and index.This provocative and important overview of the challenges of and possible approaches to climate change by an expert and shared recipient of a Nobel Peace Prize is essential reading for policy makers, climate scientists, and lay persons alike. Though the Paris Agreement on climate change was a significant achievement, most authorities agree that its measures to reduce greenhouse-gas emissions will be insufficient to offset the forecasted increase in global warming. Even in the unlikely case of ideal compliance, the Earth will still experience major climate-driven damages. Given this reality, climate expert Roger A. Sedjo argues in this book that a Plan B is required. He makes a compelling case that doing more of the same, by focusing only on the mitigation plan of the Paris Agreement, will leave humanity increasingly vulnerable; instead, we must also begin planning adaptation strategies-Plan B-which enable societies to anticipate and protect against the worst effects of inevitable climate change. The author examines several areas where environmental damage could be severe. Sea-level rise is a major concern and measures could be, and in some cases are now being, undertaken to protect coastal areas. The author also addresses the need for more robust action to ward off the likely decline in agricultural productivity, destruction of forests and biodiversity, and the impact of natural catastrophes like hurricanes made worse by climate change. In addition, he considers geo-engineering strategies, such as atmospheric reflectivity, which may play a role in lessening the impact of global warming.Introduction. Climate change : where are we now? -- Al Gore and the greenhouse gas theory : Plan A -- Natural climate change : GHGs are not the whole answer -- Plan A, mitigation : a bridge too far? -- Plan B, the adaptation solution -- Adaptation through reflectivity and geoengineering -- The politics of adaptation vs. mitigation -- "Plan B" as insurance -- Where from here? : next steps as well as summary and conclusions.1 online resourc
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
Roger A. Fortin (audio, transcript)
Get PDFDr. Roger A. Fortin continues in a long and distinguished career at Xavier University. He is an accomplished scholar, teacher, and writer. He has served Xavier University in various administrative positions, including those as Chair of the History Department, Dean of Edgecliff College of Xavier University, Interim Director of the McDonald Library, Associate Academic Vice President and lastly as the Academic Vice President and Provost.
Upon his stepping down from his position as Academic Vice President and Provost Dr. Fortin graciously agreed to be interviewed concerning his years at the University. In this conversation he imparts both personal information and his perspective upon the developments at Xavier over the years. Some topics include campus life during the turbulent 1960’s, the acquisition of the Edgecliff College campus, campus administration following the dismissal of Xavier President Fr. Charles Currie, S.J., the development of the office of Provost at Xavier University, critical historical Xavier institutional moments, and various influential Xavier administrators, teachers, and benefactors. Nearing the end of the interview he offers his perspective on Xavier in the future.
Dr. Fortin’s publications include To See Great Wonders, a history published for the 175th Anniversary of Xavier University and Faith and Action: a History of the Catholic Archdiocese of Cincinnati, 1821-1996
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
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