Institution
École centrale de Lyon
Education•Écully, Rhône-Alpes, France•
About: École centrale de Lyon is a education organization based out in Écully, Rhône-Alpes, France. It is known for research contribution in the topics: Turbulence & Finite element method. The organization has 3431 authors who have published 6299 publications receiving 140360 citations. The organization is also known as: EC-Lyon & Centralien de Lyon.
Papers published on a yearly basis
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TL;DR: In this article, the basic fundamental principles are described as well as the influence of the main parameters governing the kinetics (mass of catalyst, wavelength, initial concentration, temperature and radiant flux).
2,424 citations
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TL;DR: In this article, the TiO2/UV photocatalytic degradation of methylene blue (MB) has been investigated in aqueous heterogeneous suspensions, and it has been shown that the degradation pathway can be determined by a careful identification of intermediate products, in particular aromatics, whose successive hydroxylations lead to the aromatic ring opening.
Abstract: The TiO2/UV photocatalytic degradation of methylene blue (MB) has been investigated in aqueous heterogeneous suspensions. In addition to a prompt removal of the color, TiO2/UV-based photocatalysis was simultaneously able to oxidize the dye, with an almost complete mineralization of carbon and of nitrogen and sulfur heteroatoms into CO2 ,N H4 + ,N O3 − and SO4 2− , respectively. A detailed degradation pathway has been determined by a careful identification of intermediate products, in particular aromatics, whose successive hydroxylations lead to the aromatic ring opening. These results suggest that TiO2/UV photocatalysis may be envisaged as a method for treatment of diluted waste waters in textile industries. © 2001 Elsevier Science B.V. All rights reserved.
2,359 citations
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TL;DR: In this paper, the bonding of Si atoms at the SiO2/Si interface was determined via high-resolution core level spectroscopy with synchrotron radiation, and a model of the interface structure was obtained from the density and distribution of intermediate oxidation states.
Abstract: The bonding of Si atoms at the SiO2/Si interface is determined via high-resolution core level spectroscopy with synchrotron radiation. For oxides grown in pure O2, the SiO2/Si interface is found to contain Si atoms in intermediate oxidation states with a density of 1.5 ± 0.5 × 1015 cm−2. From the density and distribution of intermediate oxidation states, models of the interface structure are obtained. The interface is not abrupt, as evidenced by the non-ideal distribution of intermediate oxidation states and their high density (about 2 monolayers of Si). The finite width of the interface is explained by the bond density mismatch between SiO2 and Si. Annealing in H2 is found to influence the electrical parameters by removing the Pb centers that pin the Fermi level. The distribution of intermediate oxidation states is not affected.
1,543 citations
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TL;DR: In this article, the photocatalytic degradation of five various dyes has been investigated in TiO 2 /UV aqueous suspensions, and it was shown that the dyes can be degraded by varying the chemical structures, either anthraquinonic (Alizarin S), or azoic (Crocein Orange G (OG), Methyl Red (MR), Congo Red (CR)) or heteropolyaromatic (Methylene Blue (MB)).
Abstract: The photocatalytic degradation of five various dyes has been investigated in TiO 2 /UV aqueous suspensions. It was attempted to determine the feasibility of such a degradation by varying the chemical structures, either anthraquinonic (Alizarin S (AS)), or azoic (Crocein Orange G (OG), Methyl Red (MR), Congo Red (CR)) or heteropolyaromatic (Methylene Blue (MB)). In addition to a prompt removal of the colors, TiO 2 /UV-based photocatalysis was simultaneously able to fully oxidize the dyes, with a complete mineralization of carbon into CO 2 . Sulfur heteroatoms were converted into innocuous SO 4 2− ions. The mineralization of nitrogen was more complex. Nitrogen atoms in the −3 oxidation state, such as in amino-groups, remain at this reduction degree and produced NH 4 + cations, subsequently and very slowly converted into NO 3 − ions. For azo-dye (OG, MR, CR) degradation, the complete mass balance in nitrogen indicated that the central NN azo-group was converted in gaseous dinitrogen, which is the ideal issue for the elimination of nitrogen-containing pollutants, not only for environmental photocatalysis but also for any physicochemical method. The aromatic rings were submitted to successive attacks by photogenerated OH radicals leading to hydroxylated metabolites before the ring opening and the final evolution of CO 2 induced by repeated subsequent “photo-Kolbe” reactions with carboxylic intermediates. These results suggest that TiO 2 /UV photocatalysis may be envisaged as a method for treatment of diluted colored waste waters not only for decolorization, but also for detoxification, in particular in textile industries in semi-arid countries.
1,428 citations
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TL;DR: In this paper, the Eulerian time correlation coefficient of turbulent velocities passed through matched narrow-band niters shows a strong dependence on nominal filter frequency (∼ wave-number at these small turbulence levels).
Abstract: Space-time correlation measurements in the roughly isotropic turbulence behind a regular grid spanning a uniform airstream give the simplest Eulerian time correlation if we choose for the upstream probe signal a time delay which just ‘cancels’ the mean flow displacement. The correlation coefficient of turbulent velocities passed through matched narrow-band niters shows a strong dependence on nominal filter frequency (∼ wave-number at these small turbulence levels). With plausible scaling of the time separations, a scaling dependent on both wave-number and time, it is possible to effect a good collapse of the correlation functions corresponding to wave-numbers from 0·5 cm−1, the location of the peak in the three-dimensional spectrum, to 10 cm−1, about half the Kolmogorov wave-number. The spectrally local time-scaling factor is a ‘parallel’ combination of the times characterizing (i) gross strain distortion by larger eddies, (ii) wrinkling distortion by smaller eddies, (iii) convection by larger eddies and (iv) gross rotation by larger eddies.
991 citations
Authors
Showing all 3448 results
Name | H-index | Papers | Citations |
---|---|---|---|
William A. Goddard | 151 | 1653 | 123322 |
Emmanuel Mignot | 103 | 611 | 40891 |
Jose M. Guisan | 75 | 490 | 23758 |
Dmitry G. Shchukin | 70 | 247 | 15855 |
Jean Michel Martin | 66 | 258 | 17172 |
Marye Anne Fox | 66 | 379 | 16906 |
Christophe Bailly | 65 | 324 | 14901 |
Wolfgang Hackbusch | 63 | 291 | 17505 |
Ana Agüera | 63 | 168 | 12280 |
Nicole Jaffrezic-Renault | 60 | 542 | 13726 |
Pascal Simonet | 58 | 167 | 9988 |
Chantal Guillard | 55 | 208 | 12491 |
Timothy M. Vogel | 54 | 141 | 10042 |
Angelo Albini | 52 | 445 | 12126 |
Pierre Pichat | 51 | 161 | 9280 |