Preparation and Characterization of Silver Substrates Coated with Antimony-Doped SnO2 Thin Films for Surface Plasmon Resonance Studies

International audienc

Modelling and control of a seven level NPC voltage source inverter. Application to high power induction machine drive

In this paper, we study a new kind of continuous-alternating converters: a seven-level neutral point clamping (NPC) voltage source inverter (VSI). We propose this inverter for applications in high voltage and high power fields. In the first part, we develop the knowledge and the control models of this inverter using the connections functions of the semi-conductors. After that, we present two pulse width modulation (PWM) algorithms to control this converter using its control model. We propose these algorithms for digital implementation. This multilevel inverter is associated to the induction machine. The performances obtained are full of promise to use it in the high voltage and high power fields of electrical traction

Pleasantness and trigeminal sensations as salient dimensions in organizing the semantic and physiological spaces of odors

International audienc

Electrochemical preconditioning of moderately boron doped diamond electrodes: Effect of annealing

International audienc

Determination of the bond strength of some microns coatings using the laser shock technique

High power laser shocks with a 0.6 ns pulse duration have been used to study the debonding of coatings electrolytically deposited on the opposite face of the substrate than the one shocked. Experiments have been carried out on various substrate/coating systems such as stainless steel/copper or nickel and hastelloy X/platinum. Experimentally, a lower intensity debonding threshold has been determined for each of these systems. On the other hand, an upper threshold above which a systematic removal of the coating is obtained has been evidenced. By the numerical simulation of these experiments, a traction range for debonding at the interface has been determined for the three systems. A significant difference for the adhesion levels of these systems has been evidenced using this method. Thus, the possibility to use the laser shock technique as a non destructive adhesion test for coatings of some tens microns is clearly demonstrated

Growth mechanism investigation of SnO2 thin films deposited by aerosol pyrolysis for biosensor applications: Importance of the thickness

International audienceTransparent conductive oxide films are suitable sensitive layers for gas sensors and biosensors, provided that their intrinsic properties are controlled, notably considering their thickness dependence. The present paper reports on a study of the variation of some physical properties of polycrystalline Sb doped SnO2 films according to the film thickness. Films were deposited onto Si and glass substrates by aerosol pyrolysis. Their thickness was varied in a range of 20-280 nm. The electrical resistivity, the roughness, the optical constant, the microstructure and the texture were investigated. Correlated evolutions of the resistivity and the surface roughness are found in relation with the evolutions of both the microstructure and the texture. Two main successive growth steps were evidenced which are delimited by a critical film thickness. Below this thickness of approximately 100-120 nm, a strong dependence of physical properties with the thickness is evidenced whereas for thicker films no significant change is evidenced. A two-step growth model is proposed to explain this behaviour. This mechanism growth is to be considered in view of the integration of SnO2 films as sensitive layers in biosensors. Notably, in the case of biosensors based on the label-free electrochemical detection of biomolecules, it is recommended to use films with thicknesses ranging above the critical thickness value of 100-120 nm in order to obtain optimized, reproducible and comparable responses of biosensors. (c) 2012 Elsevier B.V. All rights reserved