Sandra Reemers, Ahmed Mourran, Helmut Keul, Martin Möller,
Abstract Monodisperse branched polyurethanes containing long alkyl chains have been prepared by a new convergent synthesis. This synthesis comprises two steps, with hexamethylene diisocyanate uretdione as the starting molecule. The free isocyanate groups of this monomer are reacted with long‐chain alkanols. These diurethane uretdiones are then reacted with amines or amino alcohols under ring opening and the formation of a biuret group. Branching points are not, as usual, part of the monomer but ...
Tópico(s): Advanced Polymer Synthesis and Characterization
2006 - Wiley | Journal of Polymer Science Part A Polymer Chemistry
Abstract The crystal structures of three new coordination compounds have been determined by X-ray diffraction: reaction of the enantiomerically pure ligands R-1-(4′-methoxyphenyl)ethylamine and S-1-(4′-chlorophenyl)ethylamine with [Co(Hdmg)2(NO2)(H2O)] (Hdmg = dimethylglyoximate) results in a pair of quasi-racemic complexes. Despite their different molecular conformations in the solid state these compounds can be cocrystallized to give a well-ordered binary solid of superior packing efficiency in ...
Tópico(s): Metal complexes synthesis and properties
2002 - Elsevier BV | Inorganic Chemistry Communications
Sandra Reemers, Petra Mela, Ahmed Mourran, Sergei Magonov, Helmut Keul, Martin Möller,
Abstract First‐generation dendritic macromonomers with a methacryloyl end group on one side, long alkyl chains on the other side, and a biuret system with two urethane groups in the core have been synthesized. The synthesis comprises three steps with hexamethylene diisocyanate uretdione as the starting material. The branching points were introduced via biuret groups and the prepared macromonomers were polymerized by free and controlled radical polymerization. Depending on the reaction conditions ...
Tópico(s): Chemical Synthesis and Analysis
2007 - Wiley | Journal of Polymer Science Part A Polymer Chemistry
Produção Nacional
Revisado por pares
Deepa Senapathi, Jochen Fründ, Matthias Albrecht, Michael P. D. Garratt, David Kleijn, Brian J. Pickles, Simon G. Potts, Jiandong An, Georg K.S. Andersson, Svenja Bänsch, Parthiba Basu, Faye Benjamin, Antônio Diego M. Bezerra, Ritam Bhattacharya, Jacobus C. Biesmeijer, Brett Blaauw, Eleanor J. Blitzer, Claire Brittain, Luísa G. Carvalheiro, Daniel P. Cariveau, Pushan Chakraborty, Arnob Chatterjee, Soumik Chatterjee, Sarah Cusser, Bryan N. Danforth, Erika Degani, Breno Magalhães Freitas, Lucas A. Garibaldi, Benoît Geslin, G.A. de Groot, Tina Harrison, Brad G. Howlett, Rufus Isaacs, Shalene Jha, Björn K. Klatt, Kristin M. Krewenka, Samuel Leigh, Sandra Lindström, Yael Mandelik, Megan McKerchar, Mia Park, Gideon Pisanty, Romina Rader, Menno Reemer, Maj Rundlöf, Barbara Smith, Henrik G. Smith, Patrícia Nunes‐Silva, Ingolf Steffan‐Dewenter, Teja Tscharntke, Sean M. Webber, Duncan B. Westbury, Catrin Westphal, Jennifer B. Wickens, Victoria J. Wickens, Rachael Winfree, Hong Zhang, Alexandra‐Maria Klein,
While an increasing number of studies indicate that the range, diversity and abundance of many wild pollinators has declined, the global area of pollinator-dependent crops has significantly increased over the last few decades. Crop pollination studies to date have mainly focused on either identifying different guilds pollinating various crops, or on factors driving spatial changes and turnover observed in these communities. The mechanisms driving temporal stability for ecosystem functioning and ...
Tópico(s): Ecology and Vegetation Dynamics Studies
2021 - Royal Society | Proceedings of the Royal Society B Biological Sciences
Produção Nacional
Revisado por pares
Romina Rader, Ígnasi Bartomeus, Lucas A. Garibaldi, Michael P. D. Garratt, Brad G. Howlett, Rachael Winfree, Saul A. Cunningham, Margaret M. Mayfield, Anthony D. Arthur, Georg K.S. Andersson, Riccardo Bommarco, Claire Brittain, Luísa G. Carvalheiro, Natacha P. Chacoff, Martin H. Entling, Benjamin Foully, Breno Magalhães Freitas, Barbara Gemmill‐Herren, Jaboury Ghazoul, Sean R. Griffin, C. L. Gross, Lina Herbertsson, Félix Herzog, Juliana Hipólito, Sue Jaggar, Frank Jauker, Alexandra‐Maria Klein, David Kleijn, Smitha Krishnan, Camila Queiroz Lemos, Sandra Lindström, Yael Mandelik, Victor Magalhães Monteiro, Warrick Nelson, L. Anders Nilsson, David E. Pattemore, Natália de Oliveira Pereira, Gideon Pisanty, Simon G. Potts, Menno Reemer, Maj Rundlöf, Cory S. Sheffield, Jeroen Scheper, Christof Schüepp, Henrik G. Smith, Dara A. Stanley, Jane C. Stout, Hajnalka Szentgyörgyi, Hisatomo Taki, Carlos Vergara, Blandina Felipe Viana, Michał Woyciechowski,
Significance Many of the world’s crops are pollinated by insects, and bees are often assumed to be the most important pollinators. To our knowledge, our study is the first quantitative evaluation of the relative contribution of non-bee pollinators to global pollinator-dependent crops. Across 39 studies we show that insects other than bees are efficient pollinators providing 39% of visits to crop flowers. A shift in perspective from a bee-only focus is needed for assessments of crop pollinator biodiversity ...
Tópico(s): Plant Parasitism and Resistance
2015 - National Academy of Sciences | Proceedings of the National Academy of Sciences