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Villeurbanne, France

Boulange L.,Center Detudes Et Of Recherches | Bonin E.,CPE Lyon | Saubot M.,Center Detudes Et Of Recherches
Road Materials and Pavement Design | Year: 2013

Our objective was to relate the fundamentals of bitumen-aggregate adhesion to practical engineering properties. The first step was dedicated to develop new physicochemical methods to characterise the bitumen-aggregate interface. Then, a relation was established between the physicochemical characterisations of the bitumen-aggregate interface and the water sensitivity of the asphalt. It was possible, by using the Drop Shape Analysis System, to apply the theory on the wetting of the textured surfaces distinguishing a one-scale roughness to a two-scale roughness on aggregate surfaces. Finally, a porosity effect corresponding to the smallest scale roughness leads to a better resistance to stripping phenomena. In addition, a chemical effect at the interface bitumen-aggregate, due to the addition of adhesion promoters in bitumen, improved the water sensitivity of the asphalt explained by an increase of the aromatics/resins ratio. © 2013 Copyright Taylor and Francis Group, LLC.

Coltuc D.,Polytechnic University of Bucharest | Becker J.-M.,CPE Lyon
European Signal Processing Conference | Year: 2015

The Wavelet Transform is not optimal for image compression. The coefficients on the same level of decomposition preserve a residual correlation which may harm the efficiency of the encoding algorithm. In the case of entropic codes, this effect can be reduced by using an appropriate coefficients scanning and long enough contexts for the conditional probabilities. Such an approach needs the knowledge of the residual correlation. This paper proposes a set of formulas for the evaluation of the coefficients correlation, based on the image and wavelet auto-correlations. The wavelet type and its length is shown to be unimportant for data decorrelation as proven by similar results on various cases. According to the proposed formulas, in the case of images with separable autocorrelation, the transformation of a coordinate preserves the other coordinate correlation. For classes of signals like images, with autocorrelation matching mathematical models, general encoding procedures could be provided based on these conclusions. © 2000 EUSIPCO.

French Atomic Energy Commission, Cpe Lyon, University Claude Bernard Lyon 1 and French National Center for Scientific Research | Date: 2012-04-20

The invention relates to a composition for synthesizing bimetallic nanoparticles, wherein the composition contains a first organometallic precursor and a second organometallic precursor having different decomposition rates and contained within an ionic liquid solution. The invention also relates to a method for synthesizing bimetallic nanoparticles, in which the composition is transformed under a hydrogen gas pressure between 0.1 and 10 MPa at a temperature between 0 and 150 C. until a suspension of bimetallic nanoparticles is obtained. The resulting nanoparticles are useful in diverse fields including the fields of catalysis and microelectronics.

French Atomic Energy Commission, French National Center for Scientific Research, University Claude Bernard Lyon 1 and Cpe Lyon | Date: 2014-02-10

The present invention relates to a method for synthesizing ionic liquids comprising a carbonate functional group characterized in that it comprises a step of reaction A without addition of lithium between a first reactant selected among an imidazolium, a pyrrolidinium or an ammonium and a second reactant being a methyl formate imidazolium. The first reactant is an imidazolium alcohol, a pyrrolidinium alcohol or an ammonium alcohol salt, the anion of which is NTf2. The second reactant is a chloromethyl formate imidazolium. The application of this method will be found in the field of green chemistry and more specifically in the production of ionic liquids which can be used in lithium batteries with a graphite electrode.

Li Y.,NXP Semiconductors | Delangle R.,CPE Lyon | Zhang X.-M.,NXP Semiconductors | Hovens B.,NXP Semiconductors
Microelectronics Reliability | Year: 2011

The reliability of SiCr-O based reprogrammable non-volatile resistive memory devices is investigated. Superior data retention performances are confirmed with a lifetime of 10 k h at 245 °C. The activation energy is determined by experiments as 1.28 eV, projecting an intrinsic data retention lifetime of more than 100 years at 175 °C. An endurance life of a thousand program/erase cycles is achieved. The impact of dielectric in direct contact with the SiCr-O film, the layout of the device and the preconditioning step on endurance life are studied. Transmission electron microscopy cross-sections are made to understand the mechanism of the endurance failure. Electro-thermal simulations are performed to gain insight on the observed phenomena and to give directions for further improvements. © 2011 Elsevier Ltd. All rights reserved.

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