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81.
Fabrice Gamboa Alexandre Janon Thierry Klein Agnès Lagnoux 《Comptes Rendus Mathematique》2013,351(7-8):307-310
We define and study a generalization of Sobol sensitivity indices for the case of a vector output. 相似文献
82.
Rufat Agalarov Martin Byrdin Fabrice Rappaport Gaozhong Shen Donald A. Bryant Art Van Der Est John H. Golbeck 《Photochemistry and photobiology》2008,84(6):1371-1380
Continuous wave (CW) and transient electron paramagnetic resonance studies have implied that when PsaF is removed genetically, the double reduction of A1A is facile, the lifetime of A1A? is shorter and the ratio of fast to slow kinetic phases increases in PS I complexes isolated with Triton X‐100 (Van der Est, A., A. I. Valieva, Y. E. Kandrashkin, G. Shen, D. A. Bryant and J. H. Golbeck [2004] Biochemistry 43 , 1264–1275). Changes in the lifetimes of A1A? and A1B? are characteristic of mutants involving the quinone binding sites, but changes in the relative amplitudes of A1A? and A1B? are characteristic of mutants involving the primary electron acceptors, A0A and A0B. Here, we measured the fast and slow phases of electron transfer from A1B? and A1A? to FX in psaF and psaE psaF null mutants using time‐resolved CW and pump‐probe optical absorption spectroscopy. The lifetime of the fast kinetic phase was found to be unaltered, but the lifetime of the slow kinetic phase was shorter in the psaF null mutant and even more so in the psaE psaF null mutant. Concomitantly, the amplitude of the fast kinetic phase increased by a factor of 1.8 and 2.0 in the psaF and psaE psaF null mutants, respectively, at the expense of the slow kinetic phase. The change in ratio of the fast to slow kinetic phases is explained as either a redirection of electron transfer through A1B at the expense of A1A, or a shortening of the lifetime of A1A? to become identical to that of A1B?. The constant lifetime and the characteristics of the near‐UV spectrum of the fast kinetic phase favor the former explanation. A unified hypothesis is presented of a displacement of the A‐jk(1) α‐helix and switchback loop, which would weaken the H‐bond from Leu722 to A1A, accounting for the acceleration of the slow kinetic phase, as well as weaken the H‐bond from Tyr696 to A0A, accounting for the bias of electron transfer in favor of the PsaB branch of cofactors. 相似文献
83.
Véronique Dupuis Nils Blanc Luis E. Diaz-Sanchez Arnaud Hillion Alexandre Tamion Florent Tournus Gustavo M. Pastor Andrei Rogalev Fabrice Wilhelm 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2013,67(2):1-4
In this paper, the one-way absorption property in one-dimensional dielectric/metal photonic crystal structure with a dielectric defect layer is studied. The effects of incident angle and state of polarization on one-way absorption behaviour of the anti-resonant (AR) mode are investigated. The normally incident wave from left to right propagation is totally allowed to penetrate to the structure but right to left propagation totally reflected at the same wavelength. It is found that, with increasing of the incident angle, the AR mode shifts to the lower wavelengths and its intensity decreases. Simultaneously, another AR mode with reversed one-way property appears at higher wavelength. The one-way behaviour on absorption is observed at the both states of polarizations but is localized on different wavelengths. Those effects, are suggesting that the proposed structure can be used as a direction sense polarization splitter or reflector/antireflector device. 相似文献
84.
Fabrice Baudoin 《Journal of Functional Analysis》2008,254(2):301-317
The purpose of this work is to give a new and short proof of the Atiyah-Singer local index theorem for the Dirac operator on the spin bundle. This proof is obtained by using heat semigroups approximations based on the truncation of Brownian Chen series. 相似文献
85.
86.
Adeline Perro Fabrice Meunier Véronique Schmitt Serge Ravaine 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,332(1):57-62
For the first time, large amount of Janus silica particles as small as 100 nm in diameter were prepared through a simple method based on the elaboration of Pickering emulsions of wax-in-water. Controlling the kinetic stabilization of wax droplets allows the fabrication of gram-sized quantities of regular asymmetric inorganic particles with high yield. In fact, our method is based on a limited coalescence process, which allows one to predict the quantity of interface which is produced when working with a known mass of wax, and thus to be sure that all introduced silica particles are adsorbed on the wax surface. To this end, the hydrophilic surface of the silica particles was made partially hydrophobic by adsorbing a known amount of surfactant: cetyltrimethylammonium bromide (CTAB). Varying the concentration in surfactant results in tuning the penetration rate of the particles in the wax droplets, leading to various dimension of the modified area. The broken spherical symmetry of the particle surface was thereafter revealed by the selective adsorption of gold nanoparticles on the amino-modified surface. 相似文献
87.
Dr. Fabrice Pointillart Dr. Thomas Cauchy Dr. Olivier Maury Yann Le Gal Dr. Stéphane Golhen Dr. Olivier Cador Dr. Lahcène Ouahab 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(39):11926-11941
The tetrathiafulvalene‐amido‐2‐pyridine‐N‐oxide ( L ) ligand has been employed to coordinate 4f elements. The architecture of the complexes mainly depends on the ionic radii of the lanthanides. Thus, the reaction of L in the same experimental protocol leads to three different molecular structure series. Binuclear [Ln2(hfac)5(O2CPhCl)( L )3] ? 2 H2O (hfac?=1,1,1,5,5,5‐hexafluoroacetylacetonate anion, O2CPhCl?=3‐chlorobenzoate anion) and mononuclear [Ln(hfac)3( L )2] complexes were obtained by using rare‐earth ions with either large (LnIII=Pr, Gd) or small (LnIII=Y, Yb) ionic radius, respectively, whereas the use of TbIII that possesses an intermediate ionic radius led to the formation of a binuclear complex of formula [Tb2(hfac)4(O2CPhCl)2( L )2]. Antiferromagnetic interactions have been observed in the three dinuclear compounds by using an extended empirical method. Photophysical properties of the coordination complexes have been studied by solid‐state absorption spectroscopy, whereas time‐dependent density functional theory (TD‐DFT) calculations have been carried out on the diamagnetic YIII derivative to build a molecular orbital diagram and to reproduce the absorption spectrum. For the [Yb(hfac)3( L )2] complex, the excitation at 19 600 cm?1 of the HOMO→LUMO+1/LUMO+2 charge‐transfer transition induces both line‐shape emissions in the near‐IR spectral range assigned to the 2F5/2→2F7/2 (9860 cm?1) ytterbium‐centered transition and a residual charge‐transfer emission around 13 150 cm?1. An efficient antenna effect that proceeds through energy transfer from the singlet excited state of the tetrathiafulvalene‐amido‐2‐pyridine‐N‐oxide chromophore is evidence of the YbIII sensitization. 相似文献
88.
This paper describes the development and validation of an analytical methodology to determine 28 polybrominated diphenyl ethers (PBDEs) in European eel (Anguilla anguilla) tissues using matrix solid-phase dispersion (MSPD) and gas chromatography coupled to triple quadrupole mass spectrometry (GC-QQQ-MS/MS). A total of 28 PBDEs were targeted, including tri- to deca-brominated congeners.The robustness and effectiveness of the proposed sample preparation procedure was demonstrated in lipid-rich eel tissues. The use of batch MSPD with activated silica gel and H2SO4-impregnated silica gel, followed by H2SO4 digestion and multilayer cartridge clean-up allowed for complete lipid removal and eliminated matrix effects during GC-QQQ-MS/MS analysis. The average PBDE recoveries from eel muscle samples spiked with PBDEs at two levels were in the range 56.2-119.0%. Precision was satisfactory since relative standard deviations were lower than 19.6%, regardless of spike level, and method quantification limits ranged between 1 and 170 pg g−1 (wet weight).The method demonstrated its successful application for the analysis of eel samples from two coastal lagoons located on the western French Mediterranean coast. All samples tested positive, but for tri- to hexa-brominated congeners only and total PBDE levels observed in this study were in the range 0.08-1.80 ng g−1 wet weight. 相似文献
89.
Göransson E Boixel J Monnereau C Blart E Pellegrin Y Becker HC Hammarström L Odobel F 《Inorganic chemistry》2010,49(21):9823-9832
The synthesis and photophysical characterization of two sets of zinc porphyrin platinum acetylide complexes are reported. The two sets of molecules differ in the way the bridging phenyl-ethynyl unit is attached to the porphyrin ring. One set is attached via an ethynyl unit on the β position, while the other set is attached via a phenyl unit on the meso position of the porphyrin. These were compared with previously studied complexes where attachment was made via an ethynyl unit on the meso position. Femtosecond transient absorption measurements showed in all systems a rapid quenching of the porphyrin singlet state. Electron transfer is suggested as the quenching mechanism, followed by an even faster recombination to form both the porphyrin ground and triplet excited states. This is supported by the variation in quenching rate and porphyrin triplet yield with solvent polarity, and the observation of an intermediate state in the meso-phenyl linked systems. The different linking motifs between the dyads resulted in significant variations in electron transfer rates. 相似文献
90.
Atsuo Yamada Kazuyuki Saka Makiko Uehara Sou Taminato Ryoji Kanno Fabrice Mauvy Claude Grenier 《Electrochemistry communications》2010,12(12):1690-1693
Electrode–electrolyte hetero-epitaxial systems for solid oxide fuel cells (SOFCs) with two different configuration of Nd2NiO4 + δ(110)//YSZ(100) and Nd2NiO4 + δ(100)//YSZ(110) were successfully fabricated by pulsed laser deposition. Thin films of Nd2NiO4 + δ approximately 20 nm thick were grown on a commercial single crystal of YSZ. The preferred two-dimensional diffusion paths of the oxide ions were perpendicular to the substrate for both configurations and showed oxygen reduction capability different from each other. This opens up new research direction focusing on the details of anisotropic catalytic activity of SOFC cathode depending on the crystalline surface. 相似文献