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1.
Guizellini Filipe Corrêa Franzin Bruno Trevizan da Silva Matheus Antonio Abra Luciana Mazotti Hojo Ossamu Pastre Iêda Aparecida Ribeiro Clóvis Augusto Paiva-Santos Carlos de Oliveira Fertonani Fernando Luis 《Journal of Thermal Analysis and Calorimetry》2021,143(1):47-60
Journal of Thermal Analysis and Calorimetry - The aim of this work is to synthesize and characterize a new structured silver–clay dried, calcined or sintered at different temperatures... 相似文献
2.
Photoisomerisation in Aminoazobenzene‐Substituted Ruthenium(II) Tris(bipyridine) Complexes: Influence of the Conjugation Pathway
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Dr. Anissa Amar Dr. Paul Savel Dr. Huriye Akdas‐Kilig Dr. Claudine Katan Prof. Hacène Meghezzi Prof. Abdou Boucekkine Dr. Jean‐Pierre Malval Dr. Jean‐Luc Fillaut 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8262-8270
Transition‐metal complexes containing stimuli‐responsive systems are attractive for applications in optical devices, photonic memory, photosensing, as well as luminescence imaging. Amongst them, photochromic metal complexes offer the possibility of combining the specific properties of the metal centre and the optical response of the photochromic group. The synthesis, the electrochemical properties and the photophysical characterisation of a series of donor–acceptor azobenzene derivatives that possess bipyridine groups connected to a 4‐dialkylaminoazobenzene moiety through various linkers are presented. DFT and TD‐DFT calculations were performed to complement the experimental findings and contribute to their interpretation. The position and nature of the linker (ethynyl, triazolyl, none) were engineered and shown to induce different electronic coupling between donor and acceptor in ligands and complexes. This in turn led to strong modulations in terms of photoisomerisation of the ligands and complexes. 相似文献
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Cyrille Grandjean Valérie Santraine Ange Polidori Hélène Gras-Masse Dominique Bonnet 《Tetrahedron letters》2004,45(17):3451-3454
The hydrazone ligation can be used to couple clustered-glycosides or glycomimetics functionalized with a hydrazino group with lipophilic glyoxylyl acid derivatives to give the corresponding amphiphiles in high yield and purity. 相似文献
5.
A new asymmetric synthesis of 2-substituted chiral chromanes has been achieved. The key step is the intramolecular conjugate addition of a phenolic nucleophile on a α,β-unsaturated ester catalyzed by Cinchona alkaloids. The high ee’s obtained with cinchonine and its derivatives have been rationalized by ab initio quantum chemistry calculations of transition state structures. 相似文献
6.
Using a double Suzuki cross-coupling reaction ortho- or para-bromobenzyl bromides are easily transformed into unsymmetrical diaryl (or heteroaryl) methanes 相似文献
7.
Jocelyn Sabatier Serge Poullain Patrick Latteux Jean Luc Thomas Alain Oustaloup 《Nonlinear dynamics》2004,38(1-2):383-400
Robust speed control of a low damped electromechanical system with backlash is studied, controlled load angular speed being not measured. The proposed control strategy combines a Luenberger observer (load angular speed and load torque disturbance estimations) and a robust CRONE controller. The observer provides estimation of the load angular speed and of the disturbance torque applied on the load. Through the computation of only three independent parameters (as many as a PID controller), the CRONE controller permits to ensure the robust speed control of the load in spite of plant parametric variations and speed observation errors. The proposed control strategy is applied to a four mass experimental test bench. 相似文献
8.
Bou-Huot Phe Véronique Bounor-Legare Laurent David Alain Michel 《Journal of Sol-Gel Science and Technology》2004,31(1-3):47-50
We study the synthesis of organic-inorganic hybrids in the molten state of the polymer without solvent, by reactive processing. The synthesis is based in a first step upon the crosslinking of ethylene vinyl acetate copolymer (EVA) through an exchange reaction between the pendant ester groups of EVA and tetrapropoxysilane (TPOS) in presence of dibutyltin oxide (DBTO) as an indispensable catalyst. Then in a second step the hydrolysis-condensation reactions of residual alkoxide groups results in silica network formation, which is covalently bonded with the organic network. An original approach was developed to correlate the evolution of the hydrolysis-condensation reactions through the assessment of propanol by gas chromatography and the evolution of the morphology through SAXS and TEM analysis. Silica-rich domains with a diameter close to 5 nm are obtained. 相似文献
9.
Lahcne Mezrag 《Mathematische Nachrichten》2004,266(1):60-67
In [5], it is proved that a bounded linear operator u, from a Banach space Y into an Lp(S, ν) factors through Lp1 (S, ν) for some p1 > 1, if Y* is of finite cotype; (S, ν) is a probability space for p = 0, and any measure space for 0 < p < 1. In this paper, we generalize this result to uv, where u : Y → Lp(S, ν) and v : X → Y are linear operators such that v* is of finite Ka?in cotype. This result gives also a new proof of Grothendieck's theorem. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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