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91.
Soient k un corps de caractéristique 0 et X une k[[t]]-variété (éventuellement singulière) plate, purement de dimension relative d. Nous prouvons la rationalité des séries de Poincaré motiviques et de fonctions Zêta dIgusa motiviques, associées à X, à laide de lintégration motivique, du théorème de désingularisation plongée dHironaka, de la théorie des modèles de Néron faibles pour les schémas formels et dun théorème délimination des quantificateurs en théorie des modèles.Revised version: 17 March 2004 相似文献
92.
We show that every finite subgroup of U(2) is contained with index two in a group generated by involutions fixing Lagrangian planes. We describe fundamental domains for their action on
related to the configuration of these Lagrangian planes. 相似文献
93.
A.?DébarreEmail author R.?Jaffiol C.?Julien D.?Nutarelli A.?Richard P.?Tchénio F.?Chaput J.-P.?Boilot 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2004,28(1):67-77
Recently, different approaches have been implemented to detect single molecules with an optical dipole out of the sample plane. Principles to solve this problem of general interest have been laid but no detailed analysis has been performed to date. This paper is devoted to a quantitative analysis of the dipole orientation of out of plane molecules that we have detected by amplitude and phase masking of the input beam. The accuracy of the orientation is discussed.Received: 22 July 2003, Published online: 2 December 2003PACS:
32.50. + d Fluorescence, phosphorescence (including quenching) 相似文献
94.
Le Gal J Latapie L Gressier M Coulais Y Dartiguenave M Benoist E 《Organic & biomolecular chemistry》2004,2(6):876-883
Synthetic pathways to a range of novel semi-rigid tetradentate ligands, with sulfur, amido or amino donor groups, designed to coordinate technetium 99m have been developed. The technetium-99m complexes have been prepared and their stabilities in serum and by metathesis reaction via cysteine exchange reactions were compared. HPLC comparison of two (99m)Tc-complexes and their rhenium analogues led to the first proof of the nature of our radioactive complexes. 相似文献
95.
Julien Bichon 《Algebras and Representation Theory》2004,7(4):343-362
Let A be a compact quantum group, let nN
* and let A
aut(X
n
) be the quantum permutation group on n letters. A free wreath product construction A*w
A
aut(X
n
) is introduced. This construction provides new examples of quantum groups, and is useful to describe the quantum automorphism group of the n-times disjoint union of a finite connected graph. 相似文献
96.
97.
The phase transitions to absorbing states of the branching-annihilating reaction-diffusion processes mA-->(m+k)A, nA-->(n-l)A are studied systematically in one space dimension within a new family of models. Four universality classes of nontrivial critical behavior are found. This provides, in particular, the first evidence of universal scaling laws for pair and triplet processes. 相似文献
98.
Julien Bichon 《Proceedings of the American Mathematical Society》2003,131(3):665-673
A quantum analogue of the automorphism group of a finite graph is introduced. These are quantum subgroups of the quantum permutation groups defined by Wang. The quantum automorphism group is a stronger invariant for finite graphs than the usual automorphism group. We get a quantum dihedral group .
99.
Nanoscopic scale studies of LiFePO4 as cathode material in lithium-ion batteries for HEV application
We present a review of the structural properties of LiFePO4. Depending on the mode of preparation, different impurities can poison this material. These impurities are identified and
a quantitative estimate of their concentrations is deduced from the combination of X-ray diffraction analysis, Fourier transform
infrared spectroscopy, Raman spectroscopy, and magnetic measurements. An optimized preparation provides samples with carbon-coated
particles free of any impurity phase, insuring structural stability and electrochemical performance that justify the use of
this material as a cathode element a new generation of lithium secondary batteries. 相似文献
100.
A. Lakshmi Narayana M. Dhananjaya N. Guru Prakash O. M. Hussain C. M. Julien 《Ionics》2017,23(12):3419-3428
Nanocrystalline Li2TiO3 was successfully synthesized using solid-state reaction method. The microstructural and electrochemical properties of the prepared material are systematically characterized. The X-ray diffraction pattern of the prepared material exhibits predominant (002) orientation related to the monoclinic structure with C2/c space group. HRTEM images and SAED analysis reveal the well-developed nanostructured particles with average size of ~40 nm. The electrochemical properties of the prepared sample are carried out using cyclic voltammetry (CV) and chronopotentiometry (CP) using Pt//Li2TiO3 cell in 1 mol L?1 Li2SO4 aqueous electrolyte. The Li2TiO3 electrode exhibits a specific discharge capacity of 122 mAh g?1; it can be used as anode in Li battery within the potential window 0.0–1.0 V, while investigated as a supercapacitor electrode, it delivers a specific capacitance of 317 F g?1 at a current density of 1 mA g?1 within the potential range ?0.4 to +0.4 V. The demonstration of both anodic and supercapacitor behavior concludes that the nanocrystalline Li2TiO3 is a suitable electrode material for supercapattery application. 相似文献