Publications by authors named "David Weinberger"

The concept of an active dosimetry system for pulsed radiation dose rate measurements is presented. Real-time distinction of pulsed and non-pulsed radiation contributions is based on the time structure of a single interaction. A fast tissue equivalent plastic scintillator is exploited to minimize the pile-up effect influence on absorbed energy measurements.

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An expanded family of ruthenium-based metathesis catalysts bearing cyclic alkyl amino carbene (CAAC) ligands was prepared. These catalysts exhibited exceptional activity in the ethenolysis of the seed-oil derivative methyl oleate. In many cases, catalyst turnover numbers (TONs) of more than 100,000 were achieved, at a catalyst loading of only 3 ppm.

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The synthesis of air- and moisture-stable trinuclear mixed-valence gold(I)/gold(0) clusters is described. They promote the catalytic carbonylation of amines under relatively mild conditions. The synthetic route leading to the trinuclear clusters involves a simple ligand exchange from the readily available μ(3)-oxo-[(Ph3 PAu)3O](+) complex.

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Two (cAAC)2Cu complexes, featuring a two-coordinate copper atom in the formal oxidation state zero, were prepared by reducing (Et2-cAAC)2Cu(+)I(-) with metallic sodium in THF, and by a one-pot synthesis using Me2-cAAC, Cu(II)Cl2, and KC8 in toluene in a molar ratio of 2:1:2, respectively. Both complexes are highly air and moisture sensitive but can be stored in the solid state for a month at room temperature. DFT calculations showed that in these complexes the copper center has a d(10) electronic configuration and the unpaired electron is delocalized over two carbene carbon atoms.

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Outside the cage: A change in the redox properties of a triazole fused to a carborane anion through methylation to form a zwitterion enabled facile chemical reduction of the compound to an isolable triazole radical anion (see structure: C gray, H white, N blue, B brown, Cl green). The radical anion is stabilized by kinetic protection by the chlorinated carborane and the delocalization of spin density throughout the exo-cluster π system.

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Article Synopsis
  • Researchers have developed new rare-earth coordination polymers using "light" lanthanides like Pr, Nd, Sm, and Eu with terephthalic acid through a slightly modified synthesis method.
  • The crystal structures were analyzed using Rietveld refinement, revealing isostructural networks primarily influenced by the positions of heavier elements in all four types of materials.
  • A detailed luminescence study demonstrated unique emissions from praseodymium and samarium in the visible spectrum, as well as strong europium luminescence and near-infrared emissions in neodymium-based MOFs.
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Marty Echt, the new head of marketing at Hunsk Engines, is determined to bring the motorcycle maker back to its roots. He says it's not enough to project authenticity to customers--employees must personally subscribe to the brand's values. Should the company's CEO support Marty's "real deal" vision? Five experts comment on this fictional case study.

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