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201.
Bellanger H Darmanin T Guittard F 《Langmuir : the ACS journal of surfaces and colloids》2012,28(1):186-192
As compared to superhydrophobic surfaces, the challenge to obtain superoleophobic properties, surfaces against low-surface-tension probe liquids such as hexadecane, is very important because of their high tendency to wet. From the molecular design of the monomer, it is possible to obtain in one step superoleophobic surfaces by electrodeposition. Hence, we report the synthesis and the characterization of an original series of fluorinated 3,4-ethylenedioxypyrrole (EDOP) derivatives. The electrodeposited polymer films are characterized by contact angle measurements (static and dynamic with various probe liquids), optical profilometry, and scanning electron microscopy. In the view toward reaching superoleophobic properties, a common approach is to increase the number of fluoromethylene units of the surface post-treatment agent. Here, surprisingly, it is possible, in one step, to reach more efficient antioil surface properties by decreasing the length of the fluorinated tail (F-octyl to F-hexyl). This fact can be explained by a double scale of structuration (micro and nano) induced using only F-hexyl tails. 相似文献
202.
Nana A. Kyeremateng Dr. Virginie Hornebecq Hervé Martinez Prof. Philippe Knauth Prof. Thierry Djenizian 《Chemphyschem》2012,13(16):3707-3713
Highly‐ordered Fe‐doped TiO2 nanotubes (TiO2nts) were fabricated by anodization of co‐sputtered Ti–Fe thin films in a glycerol electrolyte containing NH4F. The as‐sputtered Ti–Fe thin films correspond to a solid solution of Ti and Fe according to X‐ray diffraction. The Fe‐doped TiO2nts were studied in terms of composition, morphology and structure. The characterization included scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, UV/Vis spectroscopy, X‐ray photoelectron spectroscopy and Mott–Schottky analysis. As a result of the Fe doping, an indirect bandgap of 3.0 eV was estimated using Tauc’s plot, and this substantial red‐shift extends its photoresponse to visible light. From the Mott–Schottky analysis, the flat‐band potential (Efb) and the charge carrier concentration (ND) were determined to be ?0.95 V vs Ag/AgCl and 5.0 ×1019 cm?3 respectively for the Fe‐doped TiO2nts, whilst for the undoped TiO2nts, Efb of ?0.85 V vs Ag/AgCl and ND of 6.5×1019 cm?3 were obtained. 相似文献
203.
Ionela Iliescu Michel Boudard Stéphane Pignard Laetitia Rapenne Patrick Chaudouët Hervé Roussel 《Phase Transitions》2013,86(11):1094-1103
Optimum parameters for the growing of YMnO3 films by pulsed liquid injection metalorganic chemical vapor deposition have been studied. Si substrates were used for the optimization of the deposition process. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results show that polycrystalline single phase YMnO3 films can be obtained for an optimal ratio of Y and Mn on the injected solution and either amorphous, metastable orthorhombic, and/or hexagonal YMnO3 phases can be obtained depending on the deposition temperature and precursors ratio. In a second stage, YMnO3 films were grown on SrTiO3 substrates. Pure epitaxial orthorhombic YMnO3 phase was confirmed by XRD. The films microstructure, characterized by scanning electron microscopy and TEM, shows a columnar growth. Each columnar grain grows epitaxially with three possible orientations. 相似文献
204.
Pascal Lefèvre Daniel Li Hervé Queffélec Luis Rodríguez-Piazza 《Israel Journal of Mathematics》2013,195(2):801-824
We give examples of results on composition operators connected with lens maps. The first two concern the approximation numbers of those operators acting on the usual Hardy space H 2. The last ones are connected with Hardy-Orlicz and Bergman-Orlicz spaces ${H^\psi }$ and ${B^\psi }$ , and provide a negative answer to the question of knowing if all composition operators which are weakly compact on a non-reflexive space are norm-compact. 相似文献
205.
A wavefront sensor is used as a direct observation tool to image the Gouy phase shift in photonic nanojets created by micrometer-sized dielectric spheres. The amplitude and phase distributions of light are found in good agreement with a rigorous electromagnetic computation. Interestingly the observed phase shift when travelling through the photonic jet is a combination of the awaited π Gouy shift and a phase shift induced by the bead refraction. Such direct spatial phase shift observation using wavefront sensors would find applications in microscopy, diffractive optics, optical trapping, and point spread function engineering. 相似文献
206.
Bis(2-sulfanylethyl)amido (SEA) side-chain derivatives of aspartic and glutamic acids enable the synthesis of tail-to-side chain cyclic or branched peptides using standard Fmoc-SPPS followed by SEA native peptide ligation. 相似文献
207.
Pierre Gosselin Alain Bérard Hervé Mohrbach Subir Ghosh 《The European Physical Journal C - Particles and Fields》2009,59(4):883-889
In the present paper we have directly computed the Berry curvature terms relevant for graphene in the presence of an inhomogeneous lattice distortion. We have employed the generalized Foldy–Wouthuysen framework, developed by some of us. We show that a
non-constant lattice distortion leads to a valley–orbit coupling which is responsible for a valley–Hall effect. This is similar
to the valley–Hall effect induced by an electric field proposed in the literature and is the analogue of the spin–Hall effect
in semiconductors. Our general expressions for Berry curvature, for the special case of homogeneous distortion, reduce to
the previously obtained results. We also discuss the Berry phase in the quantization of cyclotron motion. 相似文献
208.
Capillary forces acting at the surface of a liquid drop can be strong enough to deform small objects and recent studies have provided several examples of elastic instabilities induced by surface tension. We present such an example where a liquid drop sits on a straight fiber, and we show that the liquid attracts the fiber which thereby coils inside the drop. We derive the equilibrium equations for the system, compute bifurcation curves, and show the packed fiber may adopt several possible configurations inside the drop. We use the energy of the system to discriminate between the different configurations and find a intermittent regime between two-dimensional and three-dimensional solutions as more and more fiber is driven inside the drop. 相似文献
209.
Myriam Bouhadid Nathalie Redon Hervé Plaisance Jacques Desbrières Stéphanie Reynaud 《Macromolecular Symposia》2008,268(1):9-13
Summary: The effect of humidity on the ammonia gas (NH3) detection of conducting composite films was investigated. The first results showed that the presence of humidity, acting as interference gas, modifies the behaviour of sensors in the presence of ammonia. However, the behaviour study at atmosphere without ammonia of our materials in controlled temperature and humidity allowed distinguishing atmospheric effect from NH3 pollution. 相似文献
210.
Heterodyne optical feedback on a solid-state laser is experimentally investigated as an efficient tool to characterize coherently near-field evanescent waves. A well-known topography of evanescent field is obtained via a total internal reflection of the light beam emitted by a class B Yb:Er glass laser. A subwavelength size optical fiber tip is scanned to locally probe the resulting evanescent wave in the near field. After a frequency shifting using a pair of acousto-optic modulators, the collected light is optically reinjected to excite the relaxation oscillations of the laser. The resulting dynamical response simultaneously allows very sensitive measurements of the amplitude and the phase of the evanescent wave. Extension of these preliminary results to near-field optical microscopy is suggested and discussed. 相似文献