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121.
122.
Patrick St-Onge Jérôme Gauthier Barton Wallace René Roy 《Hyperfine Interactions》2014,225(1-3):229-234
HERACLES is a multidetector that has been modified to study heavy-ion collisions, using an ion beam with an energy range between 8 to 15 MeV per nucleon. It has 78 detectors axially distributed around the beam axis in 6 rings allowing detection of multiple charged fragments from nuclear reactions. HERACLES has 4 different types of detectors, BC408/BaF2 phoswich, Si/CsI(Tl) telescope, BC408/BC444 phoswich and CsI(Tl) detectors. 25 Na?+?12 C, 25 Na?+?27 Al, 25 Mg?+?12 C and 25 Mg?+?27 Al reactions have been used to characterize the multidetector. Element identification up to Z = 12 is achieved with the BC408/BaF2 phoswich detectors, up to Z = 15 with the Si/CsI(Tl) telescopes and up to Z = 12 with the BC408/BC444 phoswich detectors. Isotopic identification is reached with the CsI(Tl) detector up to Z = 2. 相似文献
123.
G. Poulain C. BoulordD. Blanc A. KaminskiM. Gauthier C. DuboisB. Semmache M. Lemiti 《Applied Surface Science》2011,257(12):5241-5244
Silicon solar cells still require cost reduction and improved efficiency to become more competitive. New architectures can provide a significant increase in efficiency, but today most of the approaches need additional fabrication steps. In this context, laser processing offers a unique way to replace technological steps like photolithography that is not compatible with the requirements of the photovoltaic industry. In particular laser induced thermal effects can be used to activate or re-organise dopants at the silicon surface to design new emitter geometries. In this paper dopant diffusion using a nanosecond UV laser on phosphorous-doped silicon emitters is studied. The presence of a phosphosilicate glass underneath a silicon nitride layer leads to a local decrease of the emitter sheet resistance from 100 Ω/sq to 20 Ω/sq. Laser induced damage, phosphorus diffusion profile and electrical shunt are assessed in the perspective of selective emitter silicon solar cells fabrication compatible with electrochemical metal contacts deposition. 相似文献
124.
Aurlie Mac Nora Hellou Joanna Hammoud Clothilde Martin Etienne S. Gauthier Ludovic Favereau Thierry Roisnel Elsa Caytan Ghassan Nasser Nicolas Vanthuyne J. A. Gareth Williams Fabienne Berre Bertrand Carboni Jeanne Crassous 《Helvetica chimica acta》2019,102(4)
A new enantiopure cyclometallated iridium complex bearing a [4]helicenic ‐coordinating and two ‐coordinating dfppy (2‐(2,4‐difluorophenyl)‐pyridyl) ligands was prepared. This complex displayed long‐lived phosphorescence both in solution and in the solid state. Its chiroptical properties, namely electronic circular dichroism and circularly polarized luminescence, were also examined. Comparison with former chiral complexes enabled assignment of the ΔIr‐(?) and ΛIr‐(+) absolute configurations. 相似文献
125.
Dr. Lenka Pallova Dr. Etienne S. Gauthier Dr. Laura Abella Marion Jean Dr. Nicolas Vanthuyne Dr. Vincent Dorcet Dr. Laure Vendier Prof. Jochen Autschbach Dr. Jeanne Crassous Dr. Stéphanie Bastin Dr. Vincent César 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(28):7722-7730
The straightforward, multigram-scale synthesis of the partially saturated H6-fluoreno[n]helicenes (n=5 or 7) featuring a central, overcrowded alkene is described. The key cyclization step was based on an intramolecular McMurry reaction from the corresponding 1,5-diketones. Chiral stationary phase HPLC analysis and isomer separation indicate that each helicenic compound is constituted of three diastereoisomers at room temperature, i. e. the configurationally stable (R,R,P)/(S,S,M) pair of enantiomers and an apparently achiral compound resulting from the rapid interconversion between the (R,S,P) and (S,R,M) enantiomers. The partially saturated H6-fluoreno[n]helicenes are oxidatively aromatized to give an efficient access to the corresponding fluoreno[n]helicenes. The chiroptical properties (vibrational and electronic circular dichroism) of the chiral, enantiopure compounds have been measured and analyzed by quantum-chemical calculations, confirming their helicoidal nature. 相似文献
126.
Maxime Gauthier Dr. Frédéric Coutrot 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(70):17576-17580
This paper reports the synthesis and study of new pH-sensitive DB24C8-based [2]rotaxane molecular shuttles that contain within their axle four potential sites of interaction for the DB24C8: ammonium, amine, Weinreb amide, and ketone. In the protonated state, the DB24C8 lay around the best ammonium site. After either deprotonation or deprotonation-then-carbamoylation of the ammonium, different localizations of the DB24C8 were seen, depending on both the number and nature of the secondary stations and steric restriction. Unexpectedly, the results indicated that the Weinreb amide was not a proper secondary molecular station for the DB24C8. Nevertheless, through its methoxy side chain, it slowed down the shuttling of the macrocycle along the threaded axle, thereby partitioning the [2]rotaxane into two translational isomers on the NMR timescale. The ketone was successfully used as a secondary molecular station, and its weak affinity for the DB24C8 was similar to that of a secondary amine. 相似文献
127.
Pietro Tundo Fabio Aricò Guillaume Gauthier Agostino Baldacci 《Comptes Rendus Chimie》2011,14(7-8):652-655
In this work the synthesis of a tricyclic isosorbide derivative in moderate yield directly from the dicarboxymethyl isosorbide in a continuous-flow apparatus is reported. The tricyclic structure has been isolated as pure and fully characterized. This product confirms the potentiality of dimethylcarbonate (DMC) as dehydrating agent also for complicated structure and opens up further investigation and application of DMC chemistry on renewable starting materials. 相似文献
128.
Acylthioarylthioacetals are cleaved selectively by tributyltin hydride/AIBN affording thioacyls radicals, which can react with tethered carbon-carbon double or triple bond to form functionalized cyclopentanes. 相似文献
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