Search results for "Engineering sciences"

Preparation of tungstophosphoric acid/cerium-doped NH2-UiO-66 Z-scheme photocatalyst: a new candidate for green photo-oxidation of dibenzothiophene a…

2021

International audience; The goal of this study was to introduce an effective visible-light induced photocatalytic system with a good ability for photocatalytic oxidative desulfurization (PODS) and denitrogenation (PODN) using molecular oxygen (O2) as an oxidant. In this regard, tungestophosphoric acid (PW12) was supported onto cerium-doped NH2-UiO-66 (PW12/Ce-NUiO-66) and employed for the photo-oxidation of dibenzothiophene (DBT) and quinoline (Qu). Herein, using cerium (Ce) as a “mediator” facilitated the separation of charge carriers, while NH2-UiO-66 remarkably enhanced the surface area with plentiful adsorption sites and shifted the adsorption edge of PW12to the visible region. The sum …

Influence of the microstructure on the durability of hard coatings obtained from metal powders

2016

Power calculation of multi-band signals: design and implementation on FPGA

2017

International audience

PROPAGATING INTERFACES IN A TWO-LAYER BISTABLE NEURAL NETWORK

2006

The dynamics of propagating interfaces in a bistable neural network is investigated. We consider the network composed of two coupled 1D lattices and assume that they interact in a local spatial point (pin contact). The network unit is modeled by the FitzHugh–Nagumo-like system in a bistable oscillator mode. The interfaces describe the transition of the network units from the rest (unexcited) state to the excited state where each unit exhibits periodic sequences of excitation pulses or action potentials. We show how the localized inter-layer interaction provides an "excitatory" or "inhibitory" action to the oscillatory activity. In particular, we describe the interface propagation failure a…

Pinning of a kink in a nonlinear diffusive medium with a geometrical bifurcation: Theory and experiments

2004

International audience; We study the dynamics of a kink propagating in a Nagumo chain presenting a geometrical bifurcation. In the case of weak couplings, we define analytically and numerically the coupling conditions leading to the pinning of the kink at the bifurcation site. Moreover, real experiments using a nonlinear electrical lattice confirm the theoretical and numerical predictions.

Micronutrition : de la théorie à l'application en clinique

2010

National audience; Les prévisions démographiques s'attendent à un accroissement important de la population âgée et très âgée dans les décennies à venir. La prévalence des pathologies oculaires occupe la deuxième place dans cette frange de la population, laissant entrevoir une réelle explosion du coût social et économique associé à la prise en charge des patients. Pourtant, des données théoriques suggèrent que certains nutriments, en particulier lipophiles, pourraient participer à prévenir les effets du vieillissement sur la rétine et le développement pathologique. Ces hypothèses sont corroborées par des données épidémiologiques qui renforcent l'association entre la consommation d'acides gra…

A control strategy based on intelligent algorithm (PSO) to perform electrical stimulation systems

2017

International audience; Adjusting stimulation parameters using control strategy based on reliable mathematical model that can predict perfectly the muscle response, may improve the efficiency of Functional Electrical Stimulation (FES) systems. In the present project, we investigate the PID control tuning based on the Particle Swarm Optimization (PSO) algorithm at the first time in neuro-muscular systems for updating automatically the stimulation pulse amplitude to track a desired force profiles. In the beginning, The PSO algorithm is used to identify unknown force model parameters. Next, optimal PID gains are found by the same intelligent algorithm to improve the control system. The obtaine…

Extraction Methods of Essential Oils From Herbs and Spices

2017

International audience; This chapter describes both conventional and non‐conventional extraction methods of essential oils (EOs) from herbs and spices. Although hydrodistillation, steam distillation and solvent extraction are the most applied methods, several non‐conventional technologies have been evaluated, especially in respect to EO recovery, and a great potential has been attributed to these non‐conventional methods. For instance, ultrasound, microwave, supercritical fluid, pulsed electric fields, ohmic‐heating and microwave (MW) extraction techniques applied alone or combined with other techniques are potent tools to obtain EOs in a 'green' way from natural resources such as aromatic …

Proof testing and lifetime reliability of carbon fibre reinforced composite pressure vessels

2013

International audience

Effect of dietary omega-3 and omega-6 fatty acids on IOP elevation, electroretinographic changes and retinal ganglion cell loss in a laser-induced ra…

2008

International audience; Purpose:To test the efficacy of dietary omega-3 and omega-6 fatty acids in a rat model of glaucoma induced by laser photocoagulation.Methods:Male Sprague Dawley rats were fed for 3 months with a diet containing either: 1) 17% of omega-3 fatty acids (10% EPA + 7% DHA), 2) 10% of omega-6 fatty acids (as GLA), or 3) a combination of both omega-3 and omega-6 fatty acids (10% EPA + 7% DHA + 10% GLA), by comparison with a control group of animals fed with a standard diet deprived of EPA, DHA and GLA (n=10 in each group). After 3 months of diet, glaucoma was induced in one eye of each animal by laser photocoagulation (532nm) of the episcleral veins, the trabeculum and the l…