The École normale supérieure de Cachan is one of the most prestigious French Grandes Écoles. Like all the other Grandes écoles, this higher education institution is not included in the mainstream framework of the French public universities. It belongs to the Ecoles normales supérieures network, along with the Ecole normale supérieure and the Ecole normale supérieure de Lyon. Wikipedia.
French National Center for Scientific Research and Ecole Normale Superieure de Cachan | Date: 2015-06-01
Tomographs comprise at least one first emission source, one first matrix detector and calculation means arranged to produce an initial tomograph of an object on the basis of radiographs arising from the first matrix detector taken from various angles. The tomography scanner comprises a second emission source and a second matrix detector arranged so that, when the object is subjected to a stress which is known at a given instant in time, the calculation means determine the changes in the object subjected to stress based only on the information from a first radiograph of the object under stress arising from the first matrix detector, from a second radiograph of the object under stress arising from the second matrix detector and the initial tomograph, the first radiograph and the second radiograph being taken at the same given instant in time.
Agency: European Commission | Branch: FP7 | Program: CP-IP | Phase: AAT.2012.4.4-1. | Award Amount: 32.74M | Year: 2012
The continued use of composite materials in the aerospace industry has been addressed in several past research projects which have focused on new design solutions and composite manufacturing processes. However an area which has been given much less attention up until now is how to achieve a time and cost effective lean assembly production system. The current airframe assembly process of composites, metals and hybrid structures is affected by an important number of non-added value operations, which strongly cause disruptions and prevents fast ramp-up and high production rates. LOCOMACHS will focus on significantly reducing or totally eliminating the most time-consuming and hence expensive non-added value operations, e.g. temporary assembly to check gaps, shimming, dismantling and tool handling. The project will improve the design conditions which today strongly dictate the way part manufacture and assembly is performed. Important step changes will be made by dramatically improving the use of tolerance and geometrical variation management. The project will integrate existing technologies with missing breakthrough technologies developed and matured within LOCOMACHS. To support the industrialisation of future assembly production lines, key innovations such as intelligent drilling, high speed non-contact hole inspection, compact automation and active flexible tooling will be demonstrated. The design and assembly process improvements and breakthrough technologies will be validated on two physical partial wing box demonstrators, a virtual fuselage section demonstrator and additionally a virtual demonstrator showing a complete wing structure in the context of the next generation lean production flow. This Level 2 proposal is being submitted in the 5th Call FP7-AAT-2012-RTD-1 against the activity area AAT.2012.4.4-1 Integrated approach and demonstration to lean manufacturing of metal, composite and hybrid aircraft / engine structures by a Consortium led by Saab AB.
Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2013.9.7 | Award Amount: 8.27M | Year: 2013
The DIADEMS project aims at exploiting the unique physical properties of NV color centres in ultrapure single-crystal CVD-grown diamond to develop innovative devices with unprecedented performances for ICT applications. By exploiting the atom-like structure of the NV that exhibits spin dependent optical transitions, DIADEMS will make optics-based magnetometry possible.\nThe objectives of DIADEMS are to develop\n- Wide field magnetic imagers with 1 nT sensivities,\n- Scanning probe magnetometer with sensitivity 10 nT and spatial resolution 10 nm,\n- Sensor heads with resolution 1 pT.\n\nTo reach such performances, DIADEMS will:\n- Use new theoretical protocols for sensing,\n- Develop ultrahigh purity diamond material with controlled single nitrogen implantation with a precision better than 5 nm,\n- Process scanning probe tips with diametre in the 20 nm range,\n- Transfer them to AFM cantilever, improve the emission properties of NV by coupling them with photonic cavities and photonic waveguides.\n\nDIADEMS outputs will demonstrate new ICT functionalities that will boost applications with high impact on society:\n- Calibration and optimization of write/read magnetic heads for future high capacity (3 Tbit per square inch) storage disk required for intense computing,\n- Imaging of electron-spin in graphene and carbon nanotubes for next generation of electronic components based on spintronics,\n- Non-invasive investigation of living neuronal networks to understand brain function,\n- Demonstration of magnetic resonance imaging of single spins allowing single protein imaging for medical research.\n\nDIADEMS aims at integrating the efforts of the European Community on NV centres to push further the limits of this promising technology and to keep Europes prominent position.
Agency: European Commission | Branch: FP7 | Program: JTI-CS | Phase: JTI-CS-2013-1-SGO-02-070 | Award Amount: 330.30K | Year: 2013
The development of a new Iron-cobalt soft magnetic alloy is proposed with a smart combination of both high mechanical strength and moderated iron losses. The former allows higher speed of electric generator, increasing the mass power density. The later improves the thermal transfer of dissipated energies, the sustainability of the generator and help then to a further power density increase. In the complete continuation of Aperam RTD efforts these last years, this new material very recently patented has been demonstrated on laboratory scale and - in some few cases of working features on industrial tools for small quantities. But this new material is roughly defined as a new alloys family Iron-cobalt fully processed (i.e. annealed) and workable material and it needs to be optimised and fully characterized with respect to working solicitations. In the framework of this project, such a high strength new FeCo alloy will be defined in terms of processing parameters corresponding to 800MPa yield stress (R0,2) whereas several metallurgical ways will be studied to get lower iron losses than previous know ones (280W/kg at 2T/400Hz for 0,4mm thickness) without a marked decrease of R0,2. Complementary processes such as thin foils assembly, recovery or texturization will be used to reach this later target, with the help of a specialized partner (LPCES). After optimization of the lamination structure and of its microstructure, the new material will be deeply characterized mechanically and magnetomechanically (including influence of uni- or bi-axial stresses on the magnetic properties) by an other specialized partner (LMT). At the same moment some small quantities (300 to 500kg) of the optimised alloy will be processed on industrial tools and punched in pieces to provide 2 rotor stacks to theTopic Manager Company.
Snecma, Safran Group, French National Center for Scientific Research and Ecole Normale Superieure de Cachan | Date: 2013-08-30
A method of determining the non-propagation threshold of fatigue cracks at high frequency, wherein cyclic loading is exerted on at least one testpiece having an elliptical hole in a testpiece zone, the elliptical hole having a notch at one end and the testpiece being held between two rigid masses with two rigid pre-stress plates being arranged on either side of the at least one testpiece and each fastened at its two ends to the two rigid masses, which cyclic loading is at a frequency that is selected as being equal to the resonant frequency of the assembly including the testpiece, the masses, and the stress plates, so as to generate a fatigue crack from the notch, and then once it has been observed that the crack has stopped propagating, the final length of the crack is measured and a chart is used to determine the non-propagation threshold.
French National Center for Scientific Research and Ecole Normale Superieure de Cachan | Date: 2014-08-21
A method produces a monolithic electromagnetic component containing elements including a coil with turns and a base made from a ferrite. The method includes obtaining a precursor of the ferrite, depositing a first layer of the precursor in a mold, depositing the elements including the coil on the first layer, depositing a second layer of the precursor on the coil, and co-sintering the first layer, the second layer and the elements in the mold by pressure.
Institute Curie, French National Center for Scientific Research and Ecole Normale Superieure de Cachan | Date: 2014-03-26
The present invention relates to cationic triphenylamines derivatives compounds having a common structure presenting the following general formula (A) activable by visible and infra-red light for inducing and imaging apoptosis in cancer cells---- is an optional covalent bond
Haar S.,Ecole Normale Superieure de Cachan
IEEE Transactions on Automatic Control | Year: 2010
We consider asynchronous diagnosis in (safe) Petri net models of distributed systems, using the partial order semantics of occurrence net unfoldings. Both the observability and diagnosability properties will appear in two different forms, depending on the semantics chosen: strong observability and diagnosability are the classical notions from the state machine model and correspond to interleaving semantics in Petri nets. By contrast, the weak form is linked to characteristics of nonsequential processes, and requires an asynchronous progress assumption on those processes. We give algebraic characterizations for both types, and give verification methods. The study of weak diagnosability leads us to the analysis of a relation in occurrence nets, first presented in : given the occurrence of some event a that reveals b, the occurrence of b is inevitable. Then b may already have occurred, be concurrent to, or even in the future of a. We show that the reveals-relation can be effectively computed recursivelyfor each pair, a suitable finite prefix of bounded depth is sufficient-, and show its use in asynchronous diagnosis. Based on this relation, a decomposition of the Petri net unfolding into facets is defined, yielding an abstraction technique that preserves and reflects maximal partially ordered runs. © 2010 IEEE.
Clavier G.,Ecole Normale Superieure de Cachan |
Audebert P.,Ecole Normale Superieure de Cachan
Chemical Reviews | Year: 2010
The molecule, s-tetrazines can be used as building blocks for new functional molecules and molecular materials. The s-tetrazine ring is always obtained by oxidation of its 1,2- or 1,4-dihydro counterpart, which can be obtained by various methods. The cross-coupling reaction of aromatics catalyzed with palladium is a tool for C-C bond formation. The anion radicals of all tetrazines are completely stable in the absence of proton donors. The position of the absorption band corresponding to the transition is weakly influenced by the nature of the substituents and was shown not to be solvatochromic. The introduction of one benzene ring increases the photostability by an estimated factor of 30, and diphenyl-s-tetrazine is stable upon light irradiation. The fluorescence spectra of tetrazines are large and not structured in dichloromethane, while the position of the maximum of emission ranges between 550 and 590 nm.
Audebert P.,Ecole Normale Superieure de Cachan |
Miomandre F.,Ecole Normale Superieure de Cachan
Chemical Science | Year: 2013
Electrofluorochromism deals with electrochemical monitoring of luminescence features. There are several reasons to be interested in that field. The first one is the design of displays working in a similar way to electrochromic devices, substituting colors due to absorption with colors due to emission, thus producing much higher brilliance. This requires designing smart molecules and materials, which are likely to exhibit reversible switch of emission by controlling their redox state. There are also a lot of analytical applications, especially in biochemical issues, where in situ dual detection of electrochemical and fluorescence signals can lead to very sensitive and selective biosensors. To achieve this goal, instrumental developments are necessary, involving, among others, beyond diffraction limit and single molecule detection optical techniques. This paper reviews the most recent developments in the above mentioned fields of fluorescence spectroelectrochemistry, coupled detection of fluorescence and electrochemical signals and design of molecules and materials exhibiting electrofluorochromic properties. The first part describes the required features for molecular systems to exhibit a reversible switch in their luminescence properties according to a change in their redox state. Examples among organic and organometallic dyes and redox labelled fluorophores are listed. The second part focuses on the instrumental development in fluorescence spectroelectrochemistry and recent coupling of electrochemical techniques with fluorescence microscopy. Finally, some applications and devices are presented in the last part of this review. This should give an overview of this emerging research field at the interface between physics, chemistry and biology. © The Royal Society of Chemistry 2013.