Simulation d’un filtre en technologie microruban

The pedagogical product presented below is a practical work intended to the electrical engineering students, fourth year, of the National Institut of Applied Sciences of Rennes. This work is a part of filter realisation programme either in microstrip technology or lumped element. The aim of this practical work is restricted to calculate by optimizing all the basic parameters of the filter realization. Thus, an optimization and simulation work is performed on computer, by using a Touchstone software product of the Electronic Engineering Software society, to obtain parameter values close to the wished ones. This practical work is performed by groups of two students during three hours.     

60]fullerene is a powerful antioxidant in vivo with no acute or subacute toxicity

In the present work, we report the effects of C(60)-pretreatments on acute carbon tetrachloride intoxication in rats, a classical model for studying free-radical-mediated liver injury. Our results show that aqueous C(60) suspensions prepared without using any polar organic solvent not only have no acute or subacute toxicity in rodents but they also protect their livers in a dose-dependent manner against free-radical damage. To be sure, according to histopathological examinations and biological tests, pristine C(60) can be considered as a powerful liver-protective agent.     

Temperature behavior of spiral inductors on high resistivity substrate in SOI CMOS technology

This paper reviews and analyzes a compact model for integrated planar spiral inductors on standard and high resistivity substrates in silicon-on-insulator (SOI) technology. The inductors have been characterized over a temperature range from 25 to 200 °C. The temperature variation of each model parameter has been investigated. It demonstrates that only the variations of the metallic losses versus temperature have to be taken into account to model properly the high frequency behavior over a wide temperature range of a spiral inductor integrated on silicon high resistivity substrate. Based on these experimental and characterization results, guidelines for practical inductor designs in RFICs for high-temperature applications are drawn.     

ECRP: an energy-aware cluster-based routing protocol for wireless sensor networks

Energy conservation is the main issue in wireless sensor networks. Many existing clustering protocols have been proposed to balance the energy consumption and maximize the battery lifetime of sensor nodes. However, these protocols suffer from the excessive overhead due to repetitive clustering resulting in high-energy consumption. In this paper, we propose energy-aware cluster-based routing protocol (ECRP) in which not only the cluster head (CH) role rotates based on energy around all cluster members until the end of network functioning to avoid frequent re-clustering, but also it can adapt the network topology change. Further, ECRP introduces a multi-hop routing algorithm so that the energy consumption is minimized and balanced. As well, a fault-tolerant mechanism is proposed to cope up with the failure of CHs and relay nodes. We perform extensive simulations on the proposed protocol using different network scenarios. The simulation results demonstrate the superiority of ECRP compared with recent and relevant existing protocols in terms of main performance metrics.

     

Electronic and Magnetic Properties of Os-Doped Rhodium Clusters: a Theoretical Study

The stability and electronic and magnetic properties of Rh_nOs (n=?2–12) clusters in their most stable configurations were systematically studied by using density functional theory (DFT) at M06L/aug-cc-pVDZ level. Calculation of the second-order difference of energies and fragmentation energies exhibited that Rh₃Os, Rh₅Os, Rh₇Os, and Rh₉Os clusters are more stable than any other clusters. The calculated HOMO-LUMO energy gaps of the Rh_nOs clusters are found to be in the range of 0.018 to 0.299 eV, implying that the metallic behavior can appear in these clusters. Accordingly, the Rh_nOs clusters can be employed as heterogeneous nanocatalysts in many chemical reactions. The local Fukui function (\(f_{k}^{-} )\) has also been calculated, and the obtained results reveal that the highest \(f_{k}^{-} \) values are predicted for the Rh atoms. Therefore, the Rh atoms in the clusters are considered the most reactive sites that undergo reactions with electrophilic reagents. The analysis of the magnetic properties of the Rh_nOs clusters shows that the total magnetic moment per atom of these clusters varies from 0.67 to 1.75 µ_B/atom. And, the PDOS analysis reveals that the d orbitals play a crucial role for the magnetism of the Rh_nOs clusters, and the contribution of the s and p orbitals is small.     

Static Ferromagnetic Modulation Revealed by Neutron Scattering in La1−xCaxMnO3

Mn perovskites La_1?x Ca _x MnO₃ (0≤x0.1) have been studied by small angle neutron scattering (SANS) and “elastic” neutron scattering (ESANS). At low temperature, both experiments reveal a broad modulation centered at the same q _m whatever the q direction. This scattering pattern is typical of a liquid-like distribution of similar magnetic droplets, or large magnetic polarons.     

NARP-HPLC/MS and silver cationization fingerprinting of triacylglycerols in wild and cultivar Tunisian peanut kernels

A simple strategy to identify triacylglycerols (TAGs) in wild and cultivar peanuts was performed using on line coupling of non-aqueous reversed phase chromatography-electrospray ionization–mass spectrometry (NARP-LC-ESI–MS) with silver nitrate (AgNO₃) as a post-column additive. The combination of the structural information given by MS with chromatographic retention laws led to the determination of the structure of TAGs in wild and cultivar peanut oil. In addition, by using the MS⁵ method, the regio-specificity of the TAGs was determined. It was also demonstrated that in Tunisian peanut oil, the saturates have a preference for the sn-1/sn-3 position for the arachidonic and behenic acids. In the wild variety fatty acids with odd numbers of carbons were found and more TAGs were identified in comparison to the cultivar peanut oil.     

IARP: An Intelligent ACO-Based Routing Protocol with Multiple Mobile Sinks Support for Wireless Sensor Networks

Wireless Personal Communications - Using a single fixed sink in wireless sensor networks (WSNs) creates the hotspot problem. Recently, the mobile sink technique is considered as a good solution to...     

Stenting after optimal lesion debulking (sold) registry. Angiographic and clinical outcome

BACKGROUND: Coronary stenting has reduced restenosis in focal de novo lesions, but its impact has been less pronounced in complex lesion subsets. Preliminary data suggest a role for plaque burden in promoting intimal hyperplasia after stent implantation. The aim of this study was to test the hypothesis that plaque removal with directional atherectomy before stent implantation may lower the intensity of late neointimal hyperplasia, reducing the incidence of in-stent restenosis. METHODS AND RESULTS: Seventy-one patients with 90 lesions underwent directional atherectomy before coronary stenting. Intravascular ultrasound-guided stenting was performed in 73 lesions (81%). Clinical success was achieved in 96% of patients. Procedural complications were as follows: emergency bypass surgery in 1 patient (1.4%), who died 2 weeks later; Q-wave myocardial infarction in 2 patients (2.8%); and non-Q-wave myocardial infarction in 8 patients (11.3%). None of the patients had stent thrombosis at follow-up. Angiographic follow-up was performed in 89% of eligible patients at 5.7+/-1.7 months. Loss index was 0.33 (95% CI, 0.26 to 0.40), and angiographic restenosis was 11% (95% CI, 5% to 20%). Clinical follow-up was performed in all patients at 18+/-3 months. Target lesion revascularization was 7% (95% CI, 3% to 14%). CONCLUSIONS: Directional atherectomy followed by coronary stenting could be performed with good clinical success rate. Also, these data point to a possible reduction in angiographic restenosis and a significant reduction in the need for repeated coronary interventions. Therefore, a randomized clinical trial seems appropriate to test the validity of this approach.     

UV-curable acrylic resins for production of glass laminates

Glass laminates have been readily obtained by photocuring at ambient temperature of an acrylic adhesive consisting either of a liquid resin or a solid thermoplastic polymer. The light-induced polymerization process was followed by real-time infrared spectroscopy. Close to 100% conversion was reached within a few seconds of exposure, by taking as the photoinitiator an α-hydroxy alkylphenone or an aryl phosphine oxide. A liquid formulation containing an aliphatic polyurethane–acrylate oligomer, acrylic acid, and butyl acrylate gives the best performance in terms of reactivity, adhesion, impact resistance, and transparency. The impact resistance was further increased by introducing a polycarbonate core between the two glass plates. The solid thermoplastic polymer was obtained either by casting from a solution containing an aliphatic polyurethane, an acrylate oligomer, and the photoinitiator or by mixing these compounds in the molten state and further extrusion. The glass assembly was heated above the softening temperature (80°C) under a 1 MPa pressure and cured by a 1 min exposure to UV radiation to give a strongly adhesive laminate showing good transparency and long term weatherability. © 1995 John Wiley & Sons, Inc.