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401.
The authors present a study of experimental methods which permit the determination of the turbulent hydrodynamic characteristics of the flow within settling and agitation units. The measurements have been made by thermal anemometry implying one and three hot films. The processing of the experimental data obtained on-line in real time permits the average velocities, the turbulent fluctuations, the turbulent lengths and the dissipation rate to be obtained. 相似文献
402.
Gabriel Molas Marc Bocquet Julien Buckley Helen Grampeix Marc Gly Jean-Philippe Colonna Christophe Licitra Nvine Rochat Thomas Veyront Xavier Garros Franois Martin Pierre Brianceau Vincent Vidal Cosimo Bongiorno Salvatore Lombardo Barbara De Salvo Simon Deleonibus 《Solid-state electronics》2007,51(11-12):1540
In this paper, we evaluate the potentialities of hafnium-aluminates (HfAlO) materials as possible candidates for the interpoly dielectrics of future Flash memory devices. HfAlO layers of different thicknesses and compositions are integrated in single-layers and in Oxide/HfAlO/Oxide (OHO) triple-layer stacks, and analyzed in terms of coupling and insulating capabilities. We demonstrate that increasing the Hf content allows reducing the leakage current at high voltages but it results in a stronger leakage current at low voltages. We also show that once normalized in electric fields, the leakage current characteristics are independent of the high-k thickness. The electron conduction modes in these materials, at different temperatures, are also investigated. The activation energy increases with the Hf concentration in the HfAlO alloy, resulting in a higher leakage current at elevated temperatures. Finally, it is demonstrated that the conduction in triple-layer stacks is limited by a Poole–Frenkel conduction in the high-k layers, while the trap contribution in the case of single-layers becomes dominant when the HfAlO layer is thicker than 8 nm. 相似文献
403.
Multi-View Stereo Reconstruction and Scene Flow Estimation with a Global Image-Based Matching Score 总被引:2,自引:0,他引:2
Jean-Philippe Pons Renaud Keriven Olivier Faugeras 《International Journal of Computer Vision》2007,72(2):179-193
We present a new variational method for multi-view stereovision and non-rigid three-dimensional motion estimation from multiple
video sequences. Our method minimizes the prediction error of the shape and motion estimates. Both problems then translate
into a generic image registration task. The latter is entrusted to a global measure of image similarity, chosen depending
on imaging conditions and scene properties. Rather than integrating a matching measure computed independently at each surface
point, our approach computes a global image-based matching score between the input images and the predicted images. The matching
process fully handles projective distortion and partial occlusions. Neighborhood as well as global intensity information can
be exploited to improve the robustness to appearance changes due to non-Lambertian materials and illumination changes, without
any approximation of shape, motion or visibility. Moreover, our approach results in a simpler, more flexible, and more efficient
implementation than in existing methods. The computation time on large datasets does not exceed thirty minutes on a standard
workstation. Finally, our method is compliant with a hardware implementation with graphics processor units. Our stereovision
algorithm yields very good results on a variety of datasets including specularities and translucency. We have successfully
tested our motion estimation algorithm on a very challenging multi-view video sequence of a non-rigid scene.
Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users. 相似文献
404.
This Account covers research dating from the early 1960s in the field of low-melting molten salts and hydrates,which has recently become popular under the rubric of "ionic liquids". It covers understanding gained in the principal author's laboratories (initially in Australia, but mostly in the U.S.A.) from spectroscopic, dynamic, and thermodynamic studies and includes recent applications of this understanding in the fields of energy conversion and biopreservation. Both protic and aprotic varieties of ionic liquids are included, but recent studies have focused on the protic class because of the special applications made possible by the highly variable proton activities available in these liquids. 相似文献
405.
Molecular probe arrays printed on solid surfaces such as DNA, peptide, and protein microarrays are widely used in chemical and biomedical applications especially genomic and proteomic studies (Pollack et al 1999 Nat. Genet. 23 41-6, Houseman et al 2002 Nat. Biotechnol. 20 270-4, Sauer et al 2005 Nat. Rev. Genet. 6 465-76) as well as surface imaging and spectroscopy (Mori et al 2008 Anal. Biochem. 375 223-31, Liu et al 2006 Nat. Nanotechnol. 1 47-52, Liu 2010 IEEE J. Sel. Top. Quantum Electron. 16 662-71). Unfortunately the printed molecular spots on solid surfaces often suffer low distribution uniformity due to the lingering 'coffee stain' (Deegan et al 1997 Nature 389 827-9) problem of molecular accumulations and blotches, especially around the edge of deposition spots caused by solvent evaporation and convection processes. Here we present, without any surface chemistry modification, a unique solid surface of high-aspect-ratio silver-coated silicon nanocone arrays that allows highly uniform molecular deposition and thus subsequent uniform optical imaging and spectroscopic molecular detection. Both fluorescent Rhodamine dye molecules and unlabeled oligopeptides are printed on the metallic nanocone photonic substrate surface as circular spot arrays. In comparison with the printed results on ordinary glass slides and silver-coated glass slides, not only high printing density but uniform molecular distribution in every deposited spot is achieved. The high-uniformity and repeatability of molecular depositions on the 'coffee stain'-free nanocone surface is confirmed by laser scanning fluorescence imaging and surface enhanced Raman imaging experiments. The physical mechanism for the uniform molecular deposition is attributed to the superhydrophobicity and localized pinned liquid-solid-air interface on the silver-coated silicon nanocone surface. The unique surface properties of the presented nanocone surface enabled high-density, high-uniformity probe spotting beneficial for genomic and proteomic microarrays and surface molecular imaging. 相似文献
406.
The cerium supported palladium oxide (PdO/CeO(2)) at a low palladium loading was found very effective in catalytic ozonation of oxalate, a probe compound that is difficult to be efficiently degraded in water with hydroxyl radical oxidation and one of the major byproducts in ozonation of organic matter. The oxalate was degraded into CO(2) during the catalytic ozonation. The molar ratio of oxalate degraded to ozone consumption increased with increasing catalyst dose and decreasing ozone dosage and pH under the conditions of this study. The maximum molar ratio reached around 1, meaning that the catalyst was highly active and selective for oxalate degradation in water. The catalytic ozonation, which showed relatively stable activity, does not promote hydroxyl radical generation from ozone. Analysis with ATR-FTIR and in situ Raman spectroscopy revealed that 1) oxalate was adsorbed on CeO(2) of the catalyst forming surface complexes, and 2) O(3) was adsorbed on PdO of the catalyst and further decomposed to surface atomic oxygen (*O), surface peroxide (*O(2)), and O(2) gas in sequence. The results indicate that the high activity of the catalyst is related to the synergetic function of PdO and CeO(2) in that the surface atomic oxygen readily reacts with the surface cerium-oxalate complex. This kind of catalytic ozonation would be potentially effective for the degradation of polar refractory organic pollutants and hydrophilic natural organic matter. 相似文献
407.
Barrachina José Agustín Ren Chengfang Morisseau Christèle Vieillard Gilles Ovarlez Jean-Philippe 《Journal of Signal Processing Systems》2023,95(1):57-66
Journal of Signal Processing Systems - We present an in-depth statistical comparison among several Complex-Valued Neural Network (CVNN) models on the Oberpfaffenhofen Polarimetric Synthetic... 相似文献
408.
Eduardo Fernández Simon Février Martin Lacroix Romain Boman Jean-Philippe Ponthot 《International journal for numerical methods in engineering》2023,124(1):40-79
Despite the increasing use of the particle finite element method (PFEM) in fluid flow simulation and the outstanding success of the Generalized- (GA) time integration method, very little discussion has been devoted to their combined performance. This work aims to contribute in this regard by addressing three main aspects. First, it includes a detailed implementation analysis of the GA method in PFEM. The work recognizes and compares different implementation approaches from the literature, which differ mainly in the terms that are -interpolated (state variables or forces of momentum equation) and the type of treatment for the pressure in the time integration scheme. Second, the work compares the performance of the GA method against the Backward Euler and Newmark schemes for the solution of the incompressible Navier–Stokes equations. Third, the study is enriched by considering not only the classical velocity-pressure formulation but also the displacement-pressure formulation that is gaining interest in the fluid-structure interaction field. The work is carried out using various 2D and 3D benchmark problems such as the fluid sloshing, the solitary wave propagation, the flow around a cylinder, and the collapse of a cylindrical water column. 相似文献
409.
Salvatore Teresi Nicolas Sebe Jessy Patterson Théo Frottier Aurélie Kandazoglou Paul Noël Paolo Sgarro Damien Térébénec Nicolas Bernier Françoise Hippert Jean-Philippe Attané Laurent Vila Pierre Noé Maxen Cosset-Chéneau 《Advanced functional materials》2023,33(44):2303878
Driving a spin-logic circuit requires the production of a large output signal by spin-charge interconversion in spin-orbit readout devices. This should be possible by using topological insulators, which are known for their high spin-charge interconversion efficiency. However, high-quality topological insulators have so far only been obtained on a small scale, or with large scale deposition techniques that are not compatible with conventional industrial deposition processes. The nanopatterning and electrical spin injection into these materials have also proven difficult due to their fragile structure and low spin conductance. The fabrication of a spin-orbit readout device from the topological insulator Sb2Te3 deposited by large-scale industrial magnetron sputtering on SiO2 is presented. Despite a modification of the Sb2Te3 layer structural properties during the device nanofabrication, a sizeable output voltage is measured that can be unambiguously ascribed to a spin-charge interconversion process. The results pave the way for the integration of layered van der Waals materials in spin-logic devices. 相似文献
410.
Jean-Philippe Bouillon Chantal Wynants Zdenek Janousek Heinz G. Viehe 《Advanced Synthesis \u0026amp; Catalysis》1996,338(1):538-543
3-Trifluoroacetyl- and other 3-acyl-1-methyllactams ( 1–5 ) undergo the Robinson annelation with α,β-unsaturated ketones to produce spirocyclic cyclohexenones ( 6 ), their precursors hydroxycyclohexanones ( 7 ) or 3-acyl-3-oxobutyl-lactams ( 8 ) depending on the substitution. 相似文献