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111.
Benedetto Bozzini Andreas Bund Bertrand Busson Christophe Humbert Adriana Ispas Claudio Mele Abderrahmane Tadjeddine 《Electrochemistry communications》2010,12(1):56-60
In this paper we report an SFG/DFG investigation of the adsorption of CN? – used as a probe molecule to study the electrochemical double-layer structure – at a polycrystalline Au electrode in 1-butyl-1-methyl-pyrrolidinium bis(trifluoromethylsulfonyl) amide ([BMP][TFSA]) room-temperature ionic liquid (RTIL). The adsorption of CN? yielded single SFG and DFG bands in the range from ca. 2125 to 2135 cm?1, exhibiting a Stark tuning of ca. 3 cm?1 V?1. Vibrational resonances – corresponding to modes of the RTIL coadsorbed with CN?, were found in the range from ca. 1200 to 1500 cm?1. The study of the double-layer structure was complemented by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements, from which the differential double-layer capacity (CDL) was estimated. 相似文献
112.
An application of the Horner-Wadsworth-Emmons reaction carried out on a ruthenium compound as the electrophilic precursor is described for the synthesis of fused donor-acceptor system 1 based on an extended tetrathiafulvalene and a ruthenium complex of dipyridoquinoxaline units. 相似文献
113.
Clementine Cailleteau Ludovic Micallef Clemence Lepage Philippe Jean-Paul Cardot Jean-Louis Beneytout Bertrand Liagre Serge Battu 《Analytical and bioanalytical chemistry》2010,398(3):1273-1283
Differentiation therapy could be one strategy for stopping cancer cell proliferation. A plant steroid, diosgenin, is known
to induce megakaryocytic differentiation in human erythroleukemia (HEL) cells. In recent studies, the use of sedimentation
field-flow fractionation (SdFFF) allowed the preparation of subpopulations that may differ in regard to sensitivity to differentiation
induction. The specific goal of this study was to determine the relationship between cell cycle stage and sensitivity to megakaryocytic
differentiation induction of HEL cells. After first confirming the capacity of diosgenin to specifically select targets, hyperlayer
SdFFF cell sorting was used to prepare fractions according to cell cycle position from crude HEL cells. The sensitivities
of these fractions to diosgenin-induced differentiation were then tested. The coupling of SdFFF cell separation to imaging
flow cytometry showed that G1-phase cells were more sensitive to differentiation induction than S/G2M-phase cells, confirming
the relationship between cell status at the start of induction, the extent of the biological event, and the potential of SdFFF
in cancer research. 相似文献
114.
Thierry Benoist Bertrand Estellon Fr��d��ric Gardi Romain Megel Karim Nouioua 《4OR: A Quarterly Journal of Operations Research》2011,9(3):299-316
This paper introduces LocalSolver 1.x, a black-box local-search solver for general 0-1 programming. This software allows OR
practitioners to focus on the modeling of the problem using a simple formalism, and then to defer its actual resolution to
a solver based on efficient and reliable local-search techniques. Started in 2007, the goal of the LocalSolver project is
to offer a model-and-run approach to combinatorial optimization problems which are out of reach of existing black-box tree-search
solvers (integer or constraint programming). Having outlined the modeling formalism and the main technical features behind
LocalSolver, its effectiveness is demonstrated through an extensive computational study. The version 1.1 of LocalSolver can
be freely downloaded at and used for educational, research, or commercial purposes. 相似文献
115.
When a laser beam is absorbed in a semi-transparent material, a volume acoustic source is created owing to penetration of the laser beam inside the material and to thermoelastic transduction. Many experimental and theoretical studies have been conducted to better understand this ultrasound generation process with normal laser light incidence on the material surface. The purpose of this paper is to analyze the effects of the asymmetry caused by oblique incidence of a laser line source on the generation of acoustic waves in semi-transparent isotropic materials. Experiments on a glass plate demonstrate that such an obliquely incident laser light strongly affects bulk acoustic waves generation. Compressional and shear waves are enhanced and the loss of symmetry of the acoustic source causes asymmetrical behavior of the acoustic waves. Surprisingly, compressional-wave amplitude decreases whereas shear-wave amplitude increases in the region where the electromagnetic energy is refracted. This feature is explained by semi-analytical calculations. 相似文献
116.
We study various properties of a nonperturbative partition function which can be associated with any spectral curve. When the spectral curve arises from a matrix model, this nonperturbative partition function is given by a sum of matrix integrals over all possible filling fractions, and includes all the multi-instanton corrections to the perturbative 1/N expansion. We show that the nonperturbative partition function, which is manifestly holomorphic, is also modular and background independent: it transforms as the partition function of a twisted fermion on the spectral curve. Therefore, modularity is restored by nonperturbative corrections. We also show that this nonperturbative partition function obeys the Hirota equation and provides a natural nonperturbative completion for topological string theory on local Calabi–Yau 3-folds. 相似文献
117.
We construct a family of small analytic discs attached to Levi non-degenerate hypersurfaces in $\mathbb{C }^{n+1}$ , which is globally biholomorphically invariant. We then apply this technique to study unique determination problems along Levi non-degenerate hypersurfaces that are merely of class $\mathcal{C }^4$ . This method gives 2-jet determination results for germs of biholomorphisms, CR diffeomorphisms, as well as in the almost complex setting. 相似文献
118.
119.
Discovering the preferences and the behaviour of consumers is a key challenge in marketing. Information about such topics can be gathered through surveys in which the respondents must assign a score to a number of items. A strategy based on different latent class models can be used to analyze such data and achieve this objective: it consists in identifying groups of consumers whose response patterns are similar and characterizing them in terms of preferences and covariates. The basic latent class model can be extended by including covariates to model differences in (1) latent class probabilities and (2) conditional probabilities. A strategy for fitting and choosing a suitable model among them is proposed taking into account identifiability issues, the identification of potential covariates and the checking of goodness-of-fit. The tools to perform this analysis are implemented in the R package covLCA available from CRAN. We illustrate and explain the application of this strategy using data about the preferences of Belgian households for supermarkets. 相似文献
120.