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971.
Stefano Bosisio Antonia S. J. S. Mey Julien Michel 《Journal of computer-aided molecular design》2016,30(11):1101-1114
In the context of the SAMPL5 challenge water-cyclohexane distribution coefficients for 53 drug-like molecules were predicted. Four different models based on molecular dynamics free energy calculations were tested. All models initially assumed only one chemical state present in aqueous or organic phases. Model A is based on results from an alchemical annihilation scheme; model B adds a long range correction for the Lennard Jones potentials to model A; model C adds charging free energy corrections; model D applies the charging correction from model C to ionizable species only. Model A and B perform better in terms of mean-unsigned error (\(\hbox {MUE}=6.79<6.87<6.95 \log\) D units ? 95 % confidence interval) and determination coefficient \((\hbox {R}^2 = 0.26< 0.27< 0.28)\), while charging corrections lead to poorer results with model D (\(\hbox {MUE}=12.8<12.63<12.98\) and \(\hbox {R}^2 = 0.16<0.17<0.18\)). Because overall errors were large, a retrospective analysis that allowed co-existence of ionisable and neutral species of a molecule in aqueous phase was investigated. This considerably reduced systematic errors (\(\hbox {MUE}=1.87<1.97<2.07\) and \(\hbox {R}^2 = 0.35<0.40<0.45\)). Overall accurate \(\log D\) predictions for drug-like molecules that may adopt multiple tautomers and charge states proved difficult, indicating a need for methodological advances to enable satisfactory treatment by explicit-solvent molecular simulations. 相似文献
972.
[reaction: see text] Upon tandem Reformatsky reaction, easily accessible porphyrinic ketones give "locked" chlorinic diester. Both ketones and diesters, as bases or palladium complexes, efficiently generate singlet dioxygen, as demonstrated by trapping with cholesterol. 相似文献
973.
Joost Steverlynck Amaury De Cattelle Julien De Winter Pascal Gerbaux Guy Koeckelberghs 《Journal of polymer science. Part A, Polymer chemistry》2016,54(9):1252-1258
Conjugated graft copolymers consisting of a poly(3‐hexylthiophene) (P3HT) backbone and poly(9,9'‐dioctylfluorene) side chains (PF) with different grafting degrees were synthesized by the CuAAC reaction. The properties of these materials were studied by UV‐Vis and fluorescence spectroscopy. The former technique provides insight in their self‐assembly, while the latter is used to study the energy funneling from the PF side chains to the P3HT backbone. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1252–1258 相似文献
974.
The Multiple Facets of Iodine(III) Compounds in an Unprecedented Catalytic Auto‐amination for Chiral Amine Synthesis 下载免费PDF全文
Dr. Julien Buendia Gwendal Grelier Dr. Benjamin Darses Dr. Amanda G. Jarvis Dr. Frédéric Taran Dr. Philippe Dauban 《Angewandte Chemie (International ed. in English)》2016,55(26):7530-7533
Iodine(III) reagents are used in catalytic one‐pot reactions, first as both oxidants and substrates, then as cross‐coupling partners, to afford chiral polyfunctionalized amines. The strategy relies on an initial catalytic auto C(sp3)?H amination of the iodine(III) oxidant, which delivers an amine‐derived iodine(I) product that is subsequently used in palladium‐catalyzed cross‐couplings to afford a variety of useful building blocks with high yields and excellent stereoselectivities. This study demonstrates the concept of self‐amination of the hypervalent iodine reagents, which increases the value of the aryl moiety. 相似文献
975.
Jean-Sébastien Coron David Naccache Yvo Desmedt Andrew Odlyzko Julien P. Stern 《Designs, Codes and Cryptography》2006,38(1):41-53
At Crypto ’85, Desmedt and Odlyzko described a chosen-ciphertext attack against plain RSA encryption. The technique can also
be applied to RSA signatures and enables an existential forgery under a chosen-message attack. The potential of this attack
remained untapped until a twitch in the technique made it effective against two very popular RSA signature standards, namely
iso/iec 9796-1 and iso/iec 9796-2. Following these attacks, iso/iec 9796-1 was withdrawn and ISO/IEC 9796-2 amended. In this paper, we explain in detail Desmedt and Odlyzko’s attack as well
as its application to the cryptanalysis of iso/iec 9796-2.
AMS Classification: 11T71, 14G50, 94A60 相似文献
976.
977.
Julien Tailleur Sorin Tănase-Nicola Jorge Kurchan 《Journal of statistical physics》2006,122(4):557-595
Hamilton’s equations with noise and friction possess a hidden supersymmetry, valid for time-independent as well as periodically
time-dependent systems. It is used to derive topological properties of critical points and periodic trajectories in an elementary
way. From a more practical point of view, the formalism provides new tools to study the reaction paths in systems with separated
time scales. A ‘reduced current’ which contains the relevant part of the phase space probability current is introduced, together
with strategies for its computation. 相似文献
978.
Julien Bernard Maud Save Benoit Arathoon Bernadette Charleux 《Journal of polymer science. Part A, Polymer chemistry》2008,46(8):2845-2857
Stable monodisperse poly(vinyl acetate) (PVAc) submicronic latex particles were synthesized by ab initio batch emulsion polymerization using a dextran derivative from renewable resource as an efficient steric stabilizer. The dextranend‐functionalized by a xanthate moiety was synthesized by Huisgen's 1,3‐dipolar cycloaddition (click chemistry). It was applied as a macromolecular RAFT (reversible addition fragmentation chain transfer) agent in surfactant‐free emulsion polymerization of vinyl acetate to form in situ an amphiphilic block copolymer able to efficiently stabilize the latex particles. The method afforded the preparation of high solids content (27%) latices coated by dextran. Both the kinetic study and the molar mass analyses confirmed the involvement of the dithiocarbonate group in the emulsion polymerization process. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2845–2857, 2008 相似文献
979.
Vladimir Protopopescu Jacob Barhen Gabriel Amselem Julien Dahan 《Mathematical Methods in the Applied Sciences》2006,29(3):249-266
Recently we proposed a new feedback control algorithm for quantities describing global features of non‐linear dynamical systems. The performance of the algorithm, which is based on the concepts of non‐Lipschitzian dynamics and global targeting, has been successfully demonstrated for systems confined to one spatial dimension and for a specific targeted global quantity, namely the velocity of the centre of mass. In this paper we extend the scope of the non‐Lipschitzian control scheme to multi‐dimensional systems and different targeted quantities. We illustrate the efficiency of the non‐Lipschitzian feedback w.r.t. the ordinary (Lipschitzian) feedback, as well as the robustness and accuracy of the algorithm in a broad variety of control scenarios on the 2‐d Frenkel‐Kontorova model for nanofriction. Published in 2005 by John Wiley & Sons, Ltd. 相似文献
980.
An approximate‐state Riemann solver for the solution of hyperbolic systems of conservation laws with source terms is proposed. The formulation is developed under the assumption that the solution is made of rarefaction waves. The solution is determined using the Riemann invariants expressed as functions of the components of the flux vector. This allows the flux vector to be computed directly at the interfaces between the computational cells. The contribution of the source term is taken into account in the governing equations for the Riemann invariants. An application to the water hammer equations and the shallow water equations shows that an appropriate expression of the pressure force at the interface allows the balance with the source terms to be preserved, thus ensuring consistency with the equations to be solved as well as a correct computation of steady‐state flow configurations. Owing to the particular structure of the variable and flux vectors, the expressions of the fluxes are shown to coincide partly with those given by the HLL/HLLC solver. Computational examples show that the approximate‐state solver yields more accurate solutions than the HLL solver in the presence of discontinuous solutions and arbitrary geometries. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献