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81.
Brice Camus 《Journal of Fourier Analysis and Applications》2006,12(5):495-515
We establish spectral estimates at a critical energy level for h-pseudo-differential operators. Via a trace formula, we compute
the contribution of isolated (nonextremum) critical points under a condition of "real principal type." The main result holds
for all dimensions, for a singularity of any finite order and can be invariantly expressed in terms of the geometry of the
singularity. When the singularities are not integrable on the energy surface the results are significative since the order
w.r.t. h of the spectral distributions are bigger than in the regular
setting. 相似文献
82.
Marzin Tom Desvages Brice Creppy Adama Lépine Louis Esnault-Filet Annette Auradou Harold 《Transport in Porous Media》2020,132(2):283-297
Transport in Porous Media - Microbial-induced carbonate precipitation (MICP) in porous media is a two-step procedure: First, the suspension of bacteria is injected and some of the bacteria get... 相似文献
83.
84.
Berni E Dolain C Kauffmann B Léger JM Zhan C Huc I 《The Journal of organic chemistry》2008,73(7):2687-2694
The synthesis of various 1,8-diaza-4,5-dialkoxy-2,7-anthracene dicarboxylic acid derivatives and their incorporation into cyclic and helically folded aromatic oligoamides are reported. The ability of the diaza-anthracene monomers to undergo photoaddition or head-to-tail photodimerization was investigated in the solid state and in solution. Quantitative conversion of a monomer diester to the corresponding head-to-tail photodimer could be achieved in the solid state without protection from oxygen. The formation of an emissive excimer between two diaza-anthracene units appended at the end of a helically folded oligomer was demonstrated. Intramolecular photodimerization was not observed in this compound, possibly due to the low thermal stability of the head-to-head photoadduct. A cyclic oligoamide composed of two diaza-anthracene and two pyridine units was shown to adopt a flat conformation and to form columnar stacks in the solid state. Longer, noncyclic oligoamides composed of one or two diaza-anthracene units were shown to adopt helical conformations that exist preferentially as double helical dimers. 相似文献
85.
This study provides an evaluation of on-line solid-phase extraction (SPE) and liquid chromatography (LC) in combination with ion trap (IT) mass spectrometry for the simultaneous routine analysis of 12 antibiotics belonging to multiple classes together with carbamazepine and propranolol in sewage treatment effluents. The on-line SPE step warranted high sensitivity and high sample throughput while IT mass detection provided high selectivity for confirmation of positive samples. A single extraction procedure resulted in recoveries ranging from 40% to 120%. Limits of detection were in the 1-46 ng/L range, which constitutes an improvement of a factor of 10 with respect to the off-line SPE procedure. 相似文献
86.
An unprecedented example of concomitant harmonisation of hydrogen bonding and metal-templating to direct a topochemical [2+2] cycloaddition with quantitative yield is reported. 相似文献
87.
Luigi Genovese Brice Videau Matthieu Ospici Thierry Deutsch Stefan Goedecker Jean-François Méhaut 《Comptes Rendus Mecanique》2011,339(2-3):149-164
In this contribution we will describe in detail a Density Functional Theory method based on a Daubechies wavelets basis set, named BigDFT. We will see that, thanks to wavelet properties, this code shows high systematic convergence properties, very good performances and an excellent efficiency for parallel calculations. BigDFT code operation are also well-suited for GPU acceleration. We will discuss how the problematic of fruitfully benefit of this new technology can be match with the needs of robustness and flexibility of a complex code like BigDFT. This work may be of interest not only for expert in electronic structure calculations, but may also provide feedback to the wider community of high performance scientific computing. 相似文献
88.
In the context of multiple criteria decision analysis, we present the necessary and sufficient conditions to represent a cardinal preferential information by the Choquet integral w.r.t. a 2-additive capacity. These conditions are based on some complex cycles called cyclones. 相似文献
89.
JM García E Ocando-Mavárez T Kato DS Coll A Briceño N Saffon-Merceron A Baceiredo 《Inorganic chemistry》2012,51(15):8187-8193
The reaction of phosphine-stabilized germylenes (1a,b) with dimer complex [Rh(2)(μ-Cl)(2)(COD)(2)] leads to the corresponding phosphine-germylene-Rh(I) complexes (2a,b). Interestingly, the stability of these complexes depends strongly on the nature of the substituent of the germylene fragment. Indeed, the complex (2a) with the chloro-germylene ligand isomerizes into a metallacycle rhodium complex (3a) via germylene insertion into the Rh-Cl bond, while the complex with the phenyl-substituted germylene (2b) was isolated and represents the first stable Rh(I)-germylene complex with a Rh-Cl bond. 相似文献
90.
AbstractWe establish a large deviation principle for a reflected Poisson driven stochastic differential equation. Our motivation is to study in a forthcoming paper the problem of exit of such a process from the basin of attraction of a locally stable equilibrium associated with its law of large numbers. Two examples are described in which we verify the assumptions that we make to establish the large deviation principle. 相似文献