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1.
Leo Iu Jos A. Fuentes Mesfin E. Janka Kevin J. Fontenot Matthew L. Clarke 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(7):2142-2146
The hydroformylation of propene to give predominantly iso‐butanal has been achieved; class‐leading selectivity is possible even at higher temperatures that deliver fast conversion. Racemic rhodium complexes of bidentate phospholane phosphites derived from tropos‐biphenols and unusual solvent systems are the key to the selectivity observed. 相似文献
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A rapid, high yielding procedure for the synthesis of 2-substituted oxazolines has been achieved under microwave irradiation from alkyl and aryl nitriles and β-amino alcohols using a mild Lewis acid catalyst. 相似文献
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Split Hopkinson pressure bar experiments on soils are often carried out using a rigid steel confining ring to provide plane strain conditions, and measurements of the circumferential strain in the ring can be used to infer the radial stress on the surface of the specimen. Previous experiments have shown evidence of irregular electromagnetic interference in measurements of radial stress, which obscures the signals and impedes analysis. The development of robust constitutive models for soils in blast and impact events relies on the accurate characterisation of this behaviour, and so it is necessary to isolate and remove the source of interference. This paper uses an induction coil to identify the source of the anomalous signals, which are found to be due to induced currents in the gauge lead wires from the movement of magnetised pressure bars (martensitic stainless steel, 440C). Comparative experiments on sand and rubber specimens are used to show that the deforming soil specimen does not make a significant contribution to this activity, and recommendations are made on reducing electromagnetic interference to provide reliable radial stress measurements. 相似文献
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Eoin F. Clarke Helge Müller-Bunz Declan G. Gilheany 《Journal of organometallic chemistry》2011,696(23):3608-819
The synthesis is reported of novel P-stereogenic binaphthyl substituted monophosphines via a short five-step synthesis using a nickel coupling reaction with separation of the borane-protected diastereomeric products. Extensive coordination studies of these ligands with a number of well-known metal precursors were performed to more effectively understand their behaviour during catalysis.These ligands and some previously reported P-stereogenic ligands were tested in the rhodium catalysed asymmetric addition of phenyl boronic acid to napthaldehyde. These studies in asymmetric catalysis were used to compare the chiral induction of ligands that combine both axial and central chirality with ligands lacking P-stereogenicity. 相似文献
8.
Philipp Meysel Lothar Oellrich P. Raj Bishnoi Matthew A. Clarke 《The Journal of chemical thermodynamics》2011,43(10):1475-1479
The three-phase (vapour + liquid + solid) equilibrium conditions for semi-clathrates formed from three mixtures of (CO2 + N2), in aqueous solutions of tetra-butyl ammonium bromide (TBAB), were measured in an isochoric reactor. The experiments were conducted at temperatures between (281 and 290) K, at pressures between (1.9 and 5.9) MPa and in aqueous TBAB solutions of wTBAB = (0.05, 0.10, and 0.20). The experimental results obtained in this study were compared with previously obtained results for gas hydrates, formed from the same three mixtures of (CO2 + N2) and it was observed that semi-clathrates formed at a substantially lower pressure than did gas hydrates. 相似文献
9.
Dr. Elena Madrid Yuanyang Rong Dr. Mariolino Carta Prof. Neil B. McKeown Richard Malpass‐Evans Prof. Gary A. Attard Tomos J. Clarke Prof. Stuart H. Taylor Prof. Yi‐Tao Long Prof. Frank Marken 《Angewandte Chemie (International ed. in English)》2014,53(40):10751-10754
A highly rigid amine‐based polymer of intrinsic microporosity (PIM), prepared by a polymerization reaction involving the formation of Tröger’s base, is demonstrated to act as an ionic diode with electrolyte‐dependent bistable switchable states. 相似文献
10.
Brian Clarke 《Annals of Global Analysis and Geometry》2011,39(2):131-163
We study the manifold of all Riemannian metrics over a closed, finite-dimensional manifold. In particular, we investigate
the topology on the manifold of metrics induced by the distance function of the L
2 Riemannian metric—so-called because it induces an L
2 topology on each tangent space. It turns out that this topology on the tangent spaces gives rise to an L
1-type topology on the manifold of metrics itself. We study this new topology and its completion, which agrees homeomorphically
with the completion of the L
2 metric. We also give a user-friendly criterion for convergence (with respect to the L
2 metric) in the manifold of metrics. 相似文献