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161.
Dr. Camille Lecourt Sabrina Dhambri Khalil Yamani Dr. Guillaume Boissonnat Dr. Simon Specklin Dr. Etienne Fleury Karim Hammad Eric Auclair Serge Sablé Dr. Antonio Grondin Dr. Paola B. Arimondo Dr. François Sautel Dr. Georges Massiot Dr. Christophe Meyer Prof. Dr. Janine Cossy Dr. Geoffroy Sorin Dr. Marie-Isabelle Lannou Prof. Dr. Janick Ardisson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(11):2745-2749
A strategy for the assembly of the entire carbon backbone of a stereoisomer of the antitumor marine natural product hemicalide has been investigated. The devised convergent approach relies on Horner–Wadsworth–Emmons and Julia–Kocienski olefination reactions for the construction of the C6=C7 and C34=C35 double bonds, respectively, an aldol reaction to create the C27−C28 bond, and a Suzuki–Miyaura cross-coupling as the endgame to form the C15−C16 bond. 相似文献
162.
163.
Pascal Van Der Voort Mark B. Mitchell Etienne F. Vansant Mark G. White 《Interface Science》1997,5(2-3):169-197
One way to design a catalyst begins with a consideration of thereaction mechanism to the desired product so that only the chemistryrequired of that mechanism will be present on the surface. The reactionmechanism will suggest the structure(s) to be developed on the surface whichshould be stabilized against changes during operation. We believe that thisideal may be approached by decorating surfaces or porous powders with amonolayer of metal complexes having the desired structures. These complexesmay be partially decomposed to develop a high dispersion of the supportedmetal oxide. 相似文献
164.
Summary. We study a new class of backward stochastic differential equations, which involves the integral with respect to a continuous
increasing process. This allows us to give a probabilistic formula for solutions of semilinear partial differential equations
with Neumann boundary condition, where the boundary condition itself is nonlinear. We consider both parabolic and elliptic
equations.
Received: 27 September 1996 / In revised form: 1 December 1997 相似文献
165.
Sandra Binauld Fernande Boisson Thierry Hamaide Jean‐Pierre Pascault Eric Drockenmuller Etienne Fleury 《Journal of polymer science. Part A, Polymer chemistry》2008,46(16):5506-5517
Oligomers and polymers containing triazole units were synthesized by the copper(I)‐catalyzed 1,3‐dipolar cycloaddition step‐growth polymerization of four difunctional azides and alkynes. In a first part, monofunctional benzyl azide was used as a chain terminator for the polyaddition of 1,6‐diazidohexane and α,ω‐bis(O‐propargyl)diethylene glycol, leading to polytriazole oligomers of controlled average degree of polymerization (DPn = 3–20), to perform kinetic studies on low‐viscosity compounds. The monitoring of the step‐growth click polymerization by 1H NMR at 25, 45, and 60 °C allowed the determination of the activation energy of this click chemistry promoted polyaddition process, that is, Ea = 45 ± 5 kJ/mol. The influence of the catalyst content (0.1–5 mol % of Cu(PPh3)3Br according to azide or alkyne functionalities) was also examined for polymerization kinetics performed at 60 °C. In a second part, four high molar mass polytriazoles were synthesized from stoichiometric combinations of diazide and dialkyne monomers above with p‐xylylene diazide and α,ω‐bis(O‐propargyl)bisphenol A. The resulting polymers were characterized by DSC, TGA, SEC, and 1H NMR. Solubility and thermal properties of the resulting polytriazoles were discussed based on the monomers chemical structure and thermal analyses. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5506–5517, 2008 相似文献
166.
167.
168.
D. Lacour O. Durand J. -L. Maurice H. Jaffrs F. Nguyen Van Dau F. Petroff P. Etienne J. Humbert A. Vaurs 《Journal of magnetism and magnetic materials》2004,270(3):403-406
We have investigated the magnetic behavior and the structural properties of ferromagnetic–antiferromagnetic systems (NiFe–IrMn and Co–IrMn) deposited directly on a thin tantalum buffer layer (bottom configuration) or above a thin Al2O3 tunnel barrier layer (top configuration). In the bottom configuration, the bilayer system exhibits higher magnetic performances than in the top configuration in terms of thermal stability. We have performed a detailed structural study by X-ray diffraction and high-resolution transmission electron microscopy which allow us to establish a clear correlation between the situation of the bilayer with respect to the tunnel barrier, its texture and its magnetic properties. 相似文献
169.
We show that the space of convex Euclidean polygons with given angles is naturally a convex polyhedron in some hyperbolic space. This interpretation gives another proof of the existence of Im Hof's hyperbolic Coxeter orthoschemes. 相似文献
170.
C. Dal Cappello J. Langlois M. C. Dal Cappello B. Joulakian A. Lahmam-Bennani A. Duguet R. Tweed 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1992,23(4):389-396
Electron-impact double ionization of noble gases is investigated theoretically for the case of high incident energies (5 keV). An ab initio calculation is made including partial correlation in the initial state as well as in the final state. The results of the calculations are compared with those of other theories and with the first available (e, 3e) experimental data on krypton 4p 6. 相似文献