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121.
Clément Monteil Nathalie Bar Bernard Moreau Richard Retoux Agnès Bee Delphine Talbot Didier Villemin 《Particle & Particle Systems Characterization》2014,31(2):219-227
Novel partially phosphonated polyethylenimine polymers are developed in order to control the modification of nanoparticle (NP) surfaces. This polymer is built by an accessible one‐step process. The numerous phosphonate functions assume both a strong covalent anchoring on metal oxide NPs and a modulation of electric charges, while amino groups are associated with dispersion preservation and subsequent biofunctionalization. The zwitterionic nanomaterials obtained display a good stability toward pH and ionic strength. According to the selected percentage of phosphonation and the polymer size, zeta potential, and diameter of the particles are controlled. 相似文献
122.
Liu F Martin-Mingot A Jouannetaud MP Bachmann C Frapper G Zunino F Thibaudeau S 《The Journal of organic chemistry》2011,76(5):1460-1463
The first direct selective synthesis of novel gem-chlorofluorinated nitrogen-containing building blocks in superacid is reported. The dramatic role of the chlorine atom on the reaction is shown by in situ NMR experiments and allows the involvement of a novel original superelectrophilic activation process in superacid HF/SbF(5) to be postulated. 相似文献
123.
Introduction of a planar defect in a molecularly imprinted photonic crystal sensor for the detection of bisphenol A 总被引:1,自引:0,他引:1
Griffete N Frederich H Maître A Schwob C Ravaine S Carbonnier B Chehimi MM Mangeney C 《Journal of colloid and interface science》2011,364(1):18-23
This paper reports the preparation of a molecularly imprinted inverse opal hydrogel containing a 2D defect layer, by combining the Langmuir-Blodgett technique and the photonic crystal template method. By coupling the exceptional characteristics of molecularly imprinted polymers, sensitive to the presence of a target molecule, and those of photonic crystals in a single device, we could obtain a defect-embedded imprinted photonic polymer consisting in a three-dimensional, highly-ordered and interconnected macroporous array, where nanocavities complementary to analytes in shape and binding sites are distributed. As a proof of concept, we prepared a three-dimensional macroporous array of poly(methacrylic acid) (PMAA) containing molecular imprints of bisphenol A (BPA) and a planar defect layer consisting in macropores of different size. The optical properties of the resulting inverse opal were investigated using reflection spectroscopy. The defect layer was shown to enhance the sensitivity of the photonic crystal material, opening new possibilities towards the development smart optical sensing devices. 相似文献
124.
Sodium titanate materials are promising inorganic ion exchangers for the adsorption of strontium from aqueous solutions. Sodium
nonatitanate exhibits a layered structure consisting of titanate layers and exchangeable sodium ions between the layers. The
materials used in this study include samples synthesized by a hydrothermal method at temperatures between 60 °C and 200 °C.
Their structure, composition, and morphology were investigated with X-Ray diffraction measurements; thermogravimetric, compositional
and surface area analyses, and scanning electron microscopy. The structure, composition, and morphology depended on the synthesis
temperature. Batch kinetics experiments for the removal of strontium from aqueous solutions were performed, and the data were
fitted by a pseudo-second-order reaction model and a diffusive model. The strontium extraction capacity also depended on the
synthesis temperature and exhibited a maximum for samples synthesized at 100 °C. The sorption process occurs in one or two
diffusion-controlled steps that also depend on the synthesis temperature. These diffusion-limited steps are the boundary-layer
diffusion and intra-particle diffusion in the case of pure nonatitanate synthesized at temperatures lower than 170 °C, and
only intra-particle diffusion in the case of nonatitanate synthesized at 200 °C. 相似文献
125.
Claudio?Fontana Bernt??ksendalEmail author Agnès?Sulem 《Methodology and Computing in Applied Probability》2015,17(1):15-39
We consider a financial market model with a single risky asset whose price process evolves according to a general jump-diffusion with locally bounded coefficients and where market participants have only access to a partial information flow. For any utility function, we prove that the partial information financial market is locally viable, in the sense that the optimal portfolio problem has a solution up to a stopping time, if and only if the (normalised) marginal utility of the terminal wealth generates a partial information equivalent martingale measure (PIEMM). This equivalence result is proved in a constructive way by relying on maximum principles for stochastic control problems under partial information. We then characterize a global notion of market viability in terms of partial information local martingale deflators (PILMDs). We illustrate our results by means of a simple example. 相似文献
126.
Dr. Jean‐Charles Florès Dr. Marie‐Agnès Lacour Dr. Xavier Sallenave Prof. Françoise Serein‐Spirau Prof. Jean‐Pierre Lère‐Porte Prof. Joël J. E. Moreau Dr. Karinne Miqueu Dr. Jean‐Marc Sotiropoulos Dr. David Flot 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(23):7532-7546
π‐Conjugated thienylene? phenylene oligomers with fluorinated and dialkoxylated phenylene fragments have been designed and prepared to understand the interactions in fragment orbitals, the influence of the substituents (F, OMe) on the HOMO–LUMO gap, and the role of intramolecular non‐covalent cumulative interactions in the construction of π‐conjugated nanostructures. Their strong conjugation was also evidenced in the gas phase by UV photoelectron spectroscopy and theoretical calculations. These results can be explained by the crucial role of the relative energetic positions of the π orbitals of the dimethoxyphenylene, which was used to model the dialkoxyphenylene entity, in determining the π/π* orbital levels of the fluorinated phenylene entity. Dialkoxyphenylenes raise the HOMO orbitals, whereas fluorinated phenylenes lower the LUMO orbitals in the oligomers. In addition, the presence of S???F and H???F interactions in the fluorinated phenylene? thienylene compounds add to the S???O interactions in the mixed targets and contribute to the full conjugation in the oligomer, inducing weak inter‐ring angles between the involved aromatic cycles. These results, which showed extended conjugation of the π system, were corroborated by a narrow HOMO–LUMO gap (according to DFT calculations) and by a relatively strong maximum wavelength (as obtained by TD‐DFT calculations and experimental UV/Vis measurements). The crystallographic data of two mixed thienylene? (fluorinated and dialkoxylated phenylene) five‐ring oligomers agree with the above results and show the formation of quasi‐planar conformations with non‐covalent S???O, H???F, and S???F interactions. These studies in the solid and gas phases show the relevance of associating dialkoxyphenylene and fluorinated phenylene fragments with thiophene to lead to oligomers with improved electronic delocalization for electronic or optoelectronic devices. 相似文献
127.
Daouda Ndiaye Maryame Sy Agnès Pallier Dr. Sandra Même Isidro de Silva Dr. Sara Lacerda Dr. Aline M. Nonat Dr. Loïc J. Charbonnière Dr. Éva Tóth 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(29):12056-12061
The search for more biocompatible alternatives to Gd3+-based MRI agents, and the interest in 52Mn for PET imaging call for ligands that form inert Mn2+ chelates. Given the labile nature of Mn2+, high inertness is challenging to achieve. The strongly preorganized structure of the 2,4-pyridyl-disubstituted bispidol ligand L1 endows its Mn2+ complex with exceptional kinetic inertness. Indeed, MnL1 did not show any dissociation for 140 days in the presence of 50 equiv. of Zn2+ (37 °C, pH 6), while recently reported potential MRI agents MnPyC3A and MnPC2A-EA have dissociation half-lives of 0.285 h and 54.4 h under similar conditions. In addition, the relaxivity of MnL1 (4.28 mm −1 s−1 at 25 °C, 20 MHz) is remarkable for a monohydrated, small Mn2+ chelate. In vivo MRI experiments in mice and determination of the tissue Mn content evidence rapid renal clearance of MnL1. Additionally, L1 could be radiolabeled with 52Mn and the complex revealed good stability in biological media. 相似文献
128.
José Miguel Rodríguez-López Max Feinberg Denys Durand Gonzalo Cantalapiedra-Hijar Agnès Isserty-Thomas Isabelle Ortigues-Marty 《Accreditation and quality assurance》2016,21(2):131-142
In in vivo metabolic studies, quantifying the flux of a nutrient and/or the carbon atoms through the liver implies the analytical determination of nutrient concentrations before and after crossing the liver and of blood or plasma flux. There is a measurement uncertainty (MU) associated with each input quantity, which may compromise accurate physiological interpretations of the results. The objective of this work was to calculate the expanded MU of net fluxes of nutrients and carbon atoms through the liver of ruminants and to identify the main components that affect MUs. To this end, all quantities (i.e., nutrient concentrations, para-aminohippuric acid concentrations, hematocrit, time of infusion, and others) that influenced the final results were identified and quantified. Their associated MUs were calculated with Type A or Type B approaches. An expanded MU model was developed by combining these two approaches. In general, the relative expanded MU of the net flux of nutrients calculated in plasma was lower than that in blood. For both plasma and blood fluxes, the main components that increased MUs were identified. The net hepatic flux of carbon atoms, for example, was estimated to be (63 ± 229) mmol min?1. This high expanded MU was mainly a result of acetate concentration measurements in hepatic and portal veins. Priority strategies to reduce MUs, such as selecting an adequate matrix or using more accurate measurement methods, were identified. 相似文献
129.
Jean‐Philippe Echard Loïc Bertrand Dr. Alex von Bohlen Dr. Anne‐Solenn Le Hô Dr. Céline Paris Dr. Ludovic Bellot‐Gurlet Dr. Balthazar Soulier Agnès Lattuati‐Derieux Dr. Sylvie Thao Laurianne Robinet Dr. Bertrand Lavédrine Prof. Stéphane Vaiedelich 《Angewandte Chemie (International ed. in English)》2010,49(1):1-1
130.
Agnès Guillot Jean-Arcady Meyer 《Nonlinear dynamics, psychology, and life sciences》2000,4(4):297-309
In previous papers, we have established, through a functional analysis of the behavioral sequences recorded on laboratory mice over a twelve-hour period, the existence of two independent strategies of action selection. On the one hand, the choice of ultradian alternations of rest and activity bouts makes it possible for every mouse to maximize its net energy gain over a one-day or a one-night interval. On the other hand, the succession of acts performed within an activity bout might serve to precisely fit the metabolic needs of each animal, because the corresponding results present great inter-individual variability, with some mice increasing and others decreasing their net energy gain. To determine what kind of dynamic system could generate these successions of acts within an activity bout, we performed a nonlinear time series analysis of the energy costs related to the acts displayed by the mice during such a period. The results suggest that chaotic dynamics might be involved in action selection in mice. Thus, the variability mentioned above could be a consequence of the sensitive dependence on initial conditions associated with such dynamics, and would allow mice to rapidly adapt their metabolic needs to the ongoing situation. 相似文献