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381.
Pacureanu Liliana Avram Sorin Bora Alina Kurunczi Ludovic Crisan Luminita 《Structural chemistry》2019,30(3):911-923
Structural Chemistry - The striking structural resemblance between adenosine triphosphate (ATP) binding sites of glycogen synthase kinase-3 (GSK-3) and cyclin-dependent kinase-2 (CDK-2) raises... 相似文献
382.
383.
We study the optimal transport problem in sub-Riemannian manifolds where the cost function is given by the square of the sub-Riemannian
distance. Under appropriate assumptions, we generalize Brenier–McCann’s theorem proving existence and uniqueness of the optimal
transport map. We show the absolute continuity property of Wassertein geodesics, and we address the regularity issue of the
optimal map. In particular, we are able to show its approximate differentiability a.e. in the Heisenberg group (and under
some weak assumptions on the measures the differentiability a.e.), which allows us to write a weak form of the Monge–Ampère
equation. 相似文献
384.
385.
Hynek Bene? Jocelyne Galy Jean-Fran?ois Gérard Josef Ple?til Ludovic Valette 《Journal of Sol-Gel Science and Technology》2011,59(3):598-612
Prehydrolyzed-condensed precursors containing amino or glycido groups were prepared via sol gel process using various alkoxysilanes
in the bulk, without addition of solvent in any step of their preparation. The influence of the experimental set-up, the functionality
and ratio of alkoxysilanes, and type of catalyst, on the structure buildup was studied. In the case of amino precursors, the
sol–gel process was carried out at weak basic conditions while in the case of glycido precursors the sol–gel process was catalyzed
by acid or neutral pH. The sol–gel process was monitored by 29Si NMR in solution and the structure of the prehydrolysed-condensed precursors was characterized by small-angle X-Ray scattering.
The systems with high content of tetraethoxysilane led to the fast gel formation. In weak acid medium tetraethoxysilane formed
larger, more condensed species as well as small structures (based on Q
1, Q
2 and Q
3 species) with silanol groups. Strong acidic conditions led to the fast formation of insoluble silica particles in liquid
(sol) phase containing monomeric alkoxysilanes. The most suitable precursor formulations based on the alkoxysilanes with amino
groups, as well as the most efficient set-up, were selected and used to prepare hybrid organic/inorganic networks based on
an epoxy matrix. These networks were characterized using dynamic mechanical analysis. 相似文献
386.
Ludovic Rapp Christophe CibertSébastien Nénon Anne Patricia AlloncleMatthias Nagel Thomas LippertChristine Videlot-Ackermann Frédéric FagesPhilippe Delaporte 《Applied Surface Science》2011,257(12):5245-5249
Laser-induced forward transfer (LIFT) has been used to deposit pixels of an organic semiconductor, distyryl-quaterthiophenes (DS4T). The dynamics of the process have been investigated by shadowgraphic imaging for the nanosecond (ns) and picosecond (ps) regime on a time-scale from the laser iradiation to 1.5 μs. The morphology of the deposit has been studied for different conditions. Intermediate sacrificial layer of gold or triazene polymer has been used to trap the incident radiation. Its role is to protect the layer to be transferred from direct irradiation and to provide a mechanical impulse strong enough to eject the material. 相似文献
387.
388.
Hervé Dekkiche Antoine Buisson Adam Langlois Paul‐Ludovic Karsenti Prof. Laurent Ruhlmann Dr. Romain Ruppert Prof. Pierre Harvey 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10484-10493
We report the preparation of several new porphyrin homodimers bridged by a platinum(II) ion in which very intense electronic communication through the coordination link occurs. Moreover, the synthesis of a new porphyrin dyad and its photophysical properties are reported. This dyad exhibits the fastest singlet energy transfer ever reported for synthetic systems between a zinc(II) porphyrin and a porphyrin free base. This extremely fast transfer (~100 femtoseconds) is in the same range as the fastest one measured in natural systems. This feature is due to the platinum(II) linker, which allows for strong MO couplings between the two porphyrin units as experimentally supported by electrochemistry and corroborated by DFT computations. 相似文献
389.
Erwan Castanet Quanxiang Li Ludovic F. Dumée Christopher Garvey Rangam Rajkhowa Jin Zhang Bernard Rolfe Kevin Magniez 《Cellulose (London, England)》2016,23(6):3521-3534
Natural fibers are promising alternatives to synthetic fibers because of their sustainability, low environmental footprint and specific properties desirable for a wide range of technical engineering applications. The industrial implementation of fine grade natural bamboo fibers, including technical (100–200 microns) and elementary fibers (<30 microns) has been of increasing interest in recent times because these fibers offer a unique set of properties including high tensile strength, antibacterial and UV absorption. However to date, very little scientific effort has been devoted to fully understand the inter-correlation between their mechanical, physico-chemical, microstructural and morphological properties. In this paper, we report for the first time the structure–property relationship of elementary bamboo fibers. The impact of the inner microstructural organization of fibers (including the micro-fibrils angle) and physico-chemical factors such as the cellulose content and crystallinity index, on the tensile performance of these fibers is discussed in detail. This work also provides an insight into the application of bamboo fibers as natural and low-cost sorbent material for the removal of Cu2+ metal ions from model industrial wastewater. The metal ion adsorption properties of the fibers are correlated to surface energy analysis obtained from inverse gas chromatography. 相似文献
390.
Hélène D.S. Guerrand Ludovic D. Marciasini Thomas Gendrineau Oana Pascu Samuel Marre Sandra Pinet Michel Vaultier Cyril Aymonier Mathieu Pucheault 《Tetrahedron》2014
Palladium nanoparticles have been prepared using different techniques, CO2-assisted microfluidics coflow or thermolysis using ionic liquids. Both techniques displayed interesting activities in dehydrogenation of diisopropylamine–borane complex, and allowed performing a dehydrogenation–arylation sequence with the creation of a carbon–boron bond. 相似文献