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51.
TpRuII(CO)(Me)(NCMe) (Tp = hydridotris(pyrazolyl)borate) serves as a catalyst precursor for the conversion of benzene and ethylene or propene to alkylaromatic products. The reaction proceeds via the formation of the active catalyst TpRu(CO)(Ph)(NCMe) and is mildly selective for linear propylbenzene over isopropylbenzene. 相似文献
52.
Daniel Arteaga Renaud Parentani Enric Verdaguer 《International Journal of Theoretical Physics》2007,46(9):2227-2241
We analyse the quantum propagation of interacting particles in cosmological backgrounds. The model we use consists of a doublet
of massive scalar fields propagating in an expanding universe filled with massless radiation. The masses are much larger than
the Hubble expansion rate, so that the number of massive particles is preserved and the fields adequately described within
the adiabatic approximation. We focus on the dissipative effects related to the expansion rate by computing the imaginary
part of the self-energy. In the quasi static approximation, we recover the expected result that instantaneous decay rate is
governed by the local temperature. We then analyse the long time behavior of the propagator to unravel the secular effects
induced by the self-energy. We show that these effects can be expressed in terms of integrals of local quantities. Applications
to the trans-Planckian question are briefly discussed. 相似文献
53.
Graeme W. Carlile Robert A. Keyzers Katrina A. Teske Renaud Robert David E. Williams Roger G. Linington Christopher A. Gray Ryan M. Centko Luping Yan Suzana M. Anjos Heidi M. Sampson Donglei Zhang Jie Liao John W. Hanrahan Raymond J. Andersen David Y. Thomas 《Chemistry & biology》2012,19(10):1288-1299
54.
Renaud de Saint Denis 《Optics Communications》2008,281(18):4758-4761
Laser beam quality evaluation is generally carried out through the measurement of the M2 second-moment. This standard procedure is time consuming and is difficult to be implemented for checking, for instance, each VCSEL diode moving out of the assembly line of a high volume production factory. In this paper, we propose an alternative fast method allowing to distinguish easily a single transverse mode from a multiple transverse mode behaviour. This method is based on an electronic analysis (locking amplifier) of the local slope of the output laser characteristic, i.e. laser output power versus pumping. 相似文献
55.
56.
Fabien Cornillier Fayez F. Boctor Gilbert Laporte Jacques Renaud 《European Journal of Operational Research》2008
In the multi-period petrol station replenishment problem (MPSRP) the aim is to optimize the delivery of several petroleum products to a set of petrol stations over a given planning horizon. One must determine, for each day of the planning horizon, how much of each product should be delivered to each station, how to load these products into vehicle compartments, and how to plan vehicle routes. The objective is to maximize the total profit equal to the revenue, minus the sum of routing costs and of regular and overtime costs. This article describes a heuristic for the MPSRP. It contains a route construction and truck loading procedures, a route packing procedure, and two procedures enabling the anticipation or the postponement of deliveries. The heuristic was extensively tested on randomly generated data and compared to a previously published algorithm. Computational results confirm the efficiency of the proposed methodology. 相似文献
57.
Jean-Marc Renaud Georges Tsoupras Helen Stoeckli-Evans Raffaele Tabacchi 《Helvetica chimica acta》1989,72(6):1262-1267
The novel allenic epoxycyclohexanes 1 , and related compounds 2 and 3 have been isolated from the culture medium of Eutypa lata. Their structures were established by combination of spectroscopic and chemical techniques. Biogenetic origin and biological activity of these compounds are also discussed. 相似文献
58.
P. Boher M. Renaud J.M. Lopez-Villegas J. Schneider J.P. Chane 《Applied Surface Science》1987,30(1-4):100-107
A multipolar plasma passivation scheme controlled by in-situ ellipsometry has been developed to produce a high electrical quality InGaAs/Si3N4 interface. We have demonstrated the possibility to remove all native oxides at the InGaAs surface by heating the sample at 240°C, then using the action of a multipolar H2 plasma at 185°C, without optical degradation of the surface. The passivation by a native nitride layer is then performed using a N2 plasma, and Si3N4 is deposited. The treatment induces a reduction of the density of interface states Nss(E), and also a change of the nature of these interface states as shown by a reduction in the capture cross section σn(E). 相似文献
59.
Renaud Barbeyron Jean-Jacques Vasseur Carine Baraguey Michael Smietana 《Tetrahedron》2017,73(17):2468-2475
The iminodiacetic acid and aminodiethanol moieties are known for their ability to generate with boronic acids bicyclic structures having a strong intramolecular NB coordination. We describe here the convergent synthesis of 3′-deoxy-3′-iminodiacetic acid and 3′-deoxy-3′-aminodiethanol thymidine analogues. The abilities of these compounds to form boronate complexes with aliphatic or aromatic boronic acids were established by 1D and 2D 1H and 13C NMR. Moreover, conformational analysis of the newly synthesized compounds revealed a marked preference for an N-type sugar puckering. 相似文献
60.
Montserrat Cortina‐Puig Anastasia C. H. Scangas Zachary S. Marchese Silvana Andreescu Jean‐Louis Marty Carole Calas‐Blanchard 《Electroanalysis》2010,22(20):2429-2433
This paper describes the development of a xanthine oxidase/poly‐m‐phenylenediamine (XOD‐PPD)‐modified electrode. The biosensor was constructed by encapsulating XOD in a sol‐gel matrix deposited onto a platinum based screen‐printed electrode functionalized with a permselective PPD membrane. The hydrogen peroxide generated as a final product of the enzymatic reaction between the hypoxanthine and the XOD or by the spontaneous dismutation of superoxide radicals was selectively monitored at +700 mV. The use of a highly selective PPD layer blocked the nonspecific oxidation of other oxidizable molecules. Finally the biosensor was applied to the determination of the antioxidant capacity of acetylsalicylic acid. 相似文献