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121.
Gianluca Crippa Magali Lécureux-Mercier 《NoDEA : Nonlinear Differential Equations and Applications》2013,20(3):523-537
In this paper, we prove existence and uniqueness of measure solutions for the Cauchy problem associated to the (vectorial) continuity equation with a non-local flow. We also give a stability result with respect to various parameters. 相似文献
122.
Magali Deleu Sylvain Gatard Emeline Payen Laurence Lins Katherine Nott Christelle Flore Romain Thomas Michel Paquot Sandrine Bouquillon 《Comptes Rendus Chimie》2012,15(1):68-74
A two-step synthesis, with good yields, of d-xylose-based bolaamphiphiles is described. The monolayer properties, the adsorption behavior and membrane destabilization properties of two bolaamphiphiles differing by their spacers (presence or absence of one double bond) were studied. The presence of one unsaturation has no influence on the interfacial organization at low compression but impairs the stability of the monolayer at high compression. Saturated and unsaturated molecules are suggested to adopt a loop structure at the interface at low compression. The higher degree of freedom of the saturated hydrophobic spacer does not affect the initial diffusion step of the bolaform from the subphase to the interface but greatly slows the arrangement step at the interface. However, once at the interface, their surface-active properties are similar. The higher flexibility of the saturated analogue spacer also greatly increases its lipid vesicle destabilizing property. Its rearrangement within the lipid bilayer is in favour of the formation of inverted phases, facilitating membrane fusion. 相似文献
123.
Lithium as a plasma-facing component has many attractive features in fusion devices. We investigated chemical properties of the lithiated graphite surfaces during deposition using X-ray photoelectron spectroscopy and low-energy ion scattering spectroscopy. In this study we try to address some of the known issues during lithium deposition, viz., the chemical state of lithium on graphite substrate, oxide layer formation mechanisms, Li passivation effects over time, and chemical change during exposure of the sample to ambient air. X-ray photoelectron studies indicate changes in the chemical composition with various thickness of lithium on graphite during deposition. An oxide layer formation is noticed during lithium deposition even though all the experiments were performed in ultrahigh vacuum. The metal oxide is immediately transformed into carbonate when the deposited sample is exposed to air. 相似文献
124.
Raquel Andreu Javier Garín María Jesús Modrego Raquel Alicante Magali Allain 《Tetrahedron letters》2009,50(24):2920-1669
Dipolar, V-shaped compounds derived from 4H-pyranylidene-linked acceptors have been synthesized, and their linear and nonlinear optical properties (displaying μβ values up to 3000 × 10−48 esu) have been compared to those of analogous one-dimensional derivatives. The pyranylidene ring behaves strictly as a spacer, and not as a donor group. 相似文献
125.
Toussaint G Brisbois M Grandjean J Cloots R Henrist C 《Journal of colloid and interface science》2009,329(1):120-126
The surface modification of lamellar silica prepared by liquid crystal templating has been investigated. Two hydrophilic surface modifier agents, 2-glycidoxypropyltrimethoxysilane and 2-[methoxy(polyethyleneoxy)propyl)]trimethoxysilane, have been tested. Characterizations of the modified silica include thermal analysis, (13)C and (29)Si solid state NMR, transmission electron microscopy (TEM) and X-ray diffraction (XRD). The different characterizations confirmed the preservation of the lamellar morphology and the successful surface modification with both silanes along with the template elimination. The results also indicate that the structure and length of the silanes influence the final lamellar organization as well as the grafting yields and mechanisms. 相似文献
126.
We present a model of bi-phasic vesicles in the limit of large surface tension. In this regime, the vesicle is completely
stretched and well described by two spherical caps with a fold, which concentrates the membrane stress. The conservation laws
and geometric constraints restrict the space of possible shapes to a pair of solutions labeled by a parameter
given by line tension/pressure. For a given value of
, the two solutions differ by the length of the interface between domains. For a critical value,
, the two vesicle shapes become identical and no connected solution exists above this critical value. This model sheds new
light on two proposed mechanisms (osmotic shocks and molecule absorption) to explain the budding and the fission in recent
experiments. 相似文献
127.
Summary Volatile organic compounds (VOC) are present in indoor air at concentrations generally higher than in outdoor air. In this study VOC concentrations in the air of two classrooms differing in insulation, and in the expired air of children in them, were investigated. Qualitative and quantitative determinations were done by gas chromatography-mass spectrometry techniques. Differences in the concentrations of VOC in indoor air and in the expired air of the children were linked to the endogeneous or exogeneous origin of the compounds, to the activities of the children and to the quality of indoor-outdoor air exchanges. 相似文献
128.
Abdelfattah Mahmoud Sebastien Caes Magali Brisbois Raphaël P. Hermann Loris Berardo Audrey Schrijnemakers Cédric Malherbe Gauthier Eppe Rudi Cloots Bénédicte Vertruyen Frédéric Boschini 《Journal of Solid State Electrochemistry》2018,22(1):103-112
In this work, Na2FePO4F-carbon composite powders were prepared by spray-drying a solution of inorganic precursors with 10 and 20 wt% added carbon black (CB) or carbon nanotubes (CNTs). In order to compare the effect of CB and CNT when added to the precursor solutions, the structural, electrochemical, and morphological properties of the synthesized Na2FePO4F-xCB and Na2FePO4F-xCNT samples were systematically investigated. In both cases, X-ray diffraction shows that calcination at 600 °C in argon leads to the formation of Na2FePO4F as the major inorganic phase. 57Fe Mössbauer spectroscopy was used as complementary technique to probe the oxidation states, local environment, and identify the composition of the iron-containing phases. The electrochemical performance is markedly better in the case of Na2FePO4F-CNT (20 wt%), with specific capacities of about 100 mAh/g (Na2FePO4F-CNT) at C/4 rate vs. 50 mAh/g for Na2FePO4F-CB (20 wt%). SEM characterization of Na2FePO4F-CB particles revealed different particle morphologies for the Na2FePO4F-CNT and Na2FePO4F-CB powders. The carbon-poor surface observed for Na2FePO4F-CB could be due to a slow diffusion of carbon in the droplets during drying. On the contrary, Na2FePO4F-CNT shows a better CNT dispersion inside and at the surface of the NFPF particles that improves the electrochemical performance. 相似文献
129.
130.
Dr. Aude Sourdon Dr. Magali Gary-Bobo Dr. Marie Maynadier Dr. Marcel Garcia Dr. Jean-Pierre Majoral Dr. Anne-Marie Caminade Dr. Olivier Mongin Dr. Mireille Blanchard-Desce 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(14):3637-3649
The synthesis and the photophysical properties of a new class of fully organic monodisperse nanoparticles for combined two-photon imaging and photodynamic therapy are described. The design of such nanoparticles is based on the covalent immobilization of a dedicated quadrupolar dye that combines excellent two-photon absorbing (2PA) properties, fluorescence and singlet oxygen generation ability, in a phosphorous-based dendrimeric architecture. First, a bifunctional quadrupolar dye bearing two different grafting moieties, a phenol function and an aldehyde function, was synthesized. It was then covalently grafted through its phenol function to a phosphorus-based dendrimer scaffold of generation 1. The remaining aldehyde functions were then used to continue the dendrimer synthesis up to generation 2, introducing finally 24 water-solubilizing triethyleneglycol chains at its periphery. A dendrimer confining 12 photoactive quadrupolar units in its inner scaffold and showing water solubility was thus obtained. Interestingly, the G1 and G2 dendrimers retain some fluorescence as well as significant singlet oxygen production efficiencies while they were found to show very high 2PA cross-sections in a broad range of the NIR biological spectral window. Hydrophilic dendrimer G2 was tested in vitro on breast cancer cells, first in one- and two-photon microscopy, which allowed for visualization of their cell internalization, then in two-photon photodynamic therapy. While being nontoxic in the dark and, more importantly, under exposure to daylight, dendrimer G2 proved to be a very efficient cell-death inducer only under two-photon irradiation in the NIR. 相似文献