13 research outputs found

    Effect of Annealing Temperature on Structural, Optical and Electrical Properties of ZnO Thin Films Prepared by Sol-Gel Method

    Get PDF
    A transparent semiconductor ZnO thin film was prepared on glass substrates using spin coating sol-gel method. The coated ZnO films were annealed in air for 2 hours at different temperatures of 0, 450, 500, 550 and 600 °C. The films were obtained at a concentration of sol-gel solution is 0.5 M. In present paper, the structural, optical and electrical properties of the ZnO thin films were studied as a function of the annealing temperature. The DRX analyses indicated that the coated ZnO films exhibit an hexagonal structure wurtzite and (002) oriented with the maximum value of crystallite size G = 69.32 nm is measured of ZnO film annealed at 600 °C. The crystallinity of the thin films improved at high annealing temperature which was depends too few defects. Spectrophotometer (UV-vis) of a ZnO films deposited at different annealing temperatures shows an average transmittance of about 88 %. The band gap energy decreased after annealing temperature from Eg = 3.359 to 3.117 eV for without annealing and annealed films at 450 °C, respectively, than increased at 600 °C to reaching the maximum value 3.251 eV. The minimum value of the sheet resistance Rsh of the films is 107635 Ω was obtained for ZnO thin film annealed at 600 °C. The best estimated structure, optical and electrical results are achieved in annealed ZnO film at 600 °C

    Static and Dynamic Mapping Heuristics for Multiprocessor Systems-on-Chip

    No full text
    International audienceIn the Algerian republic, scientific and intensive computing are a priority in the strategy of the scientific research between 2013 and 2017. To put into practice this strategy, 32 nodes of high-performance computing were installed in Algeria in particular in the University of Oran. The work that we present in this chapter is our contribution to this priority in the area of intensive embedded computing: static and dynamic mapping heuristics for single chip systems. Thus we present a synthesis of the work done over a few years in a collaboration between the University of Oran, Algeria (LIO and then LAPECI laboratories) and the DART team of LIFL (University Lille 1, CNRS, Inria), and in partnership with the Algerian Center of spatial techniques. We study how to efficiently map intensive applications on network-on-chip based multiprocessor systems-on-chip

    Elaboration and characterization of acellular glass based culletloaded with carbon fibers

    No full text
    The foams glass whose porosity is very important, are counted among the new glass products that meet certain desired comfort needs in the particular building area (thermal and acoustic insulation). The objective of this study is to determine the influence of the carbon fibers addition influence on the porosity, the thermal insulation and dielectric loss of foams glass prepared by sintering at 800 °C, which opens the way to foam glass many possibilities for industrial to extend their opportunities that are very varied from thermal insulation to electromagnetic waves absorption. The carbon fibers addition used for this study is 1, 2, 3.5 and 5 wt% in relation to the foam glass load. Physico-chemical analysis techniques such as SEM-EDS, porosity, thermal insulation, differential thermal analysis, and dielectric tests have been used for the foams glass characterization. The obtained microstructure results clearly show that the 5 wt% carbon fibers addition increases the foam glass porosity which leads to low thermal conductivity (λ=0.0281 W/m°C) and increases its thermal insulating capacity. Furthermore the specific dielectric properties as real permittivity (ε'=2.7619) and high dielectric loss (tan δ=0.02969) favor the use of these glass filled foams with carbon fibers in the electromagnetic waves microwave absorption in the weakest working frequencies (mobile phones and Wi-Fi). © 2015 Elsevier B.V. All rights reserve

    Am J Respir Crit Care Med

    No full text
    RATIONALE: Post-cardiac surgery shock is associated with high morbidity and mortality. By removing toxins and proinflammatory mediators and correcting metabolic acidosis, high-volume hemofiltration (HVHF) might halt the vicious circle leading to death by improving myocardial performance and reducing vasopressor dependence. OBJECTIVES: To determine whether early HVHF decreases all-cause mortality 30 days after randomization. METHODS: This prospective, multicenter randomized controlled trial included patients with severe shock requiring high-dose catecholamines 3-24 hours post-cardiac surgery who were randomized to early HVHF (80 ml/kg/h for 48 h), followed by standard-volume continuous venovenous hemodiafiltration (CVVHDF) until resolution of shock and recovery of renal function, or conservative standard care, with delayed CVVHDF only for persistent, severe acute kidney injury. MEASUREMENTS AND MAIN RESULTS: On Day 30, 40 of 112 (36%) HVHF and 40 of 112 (36%) control subjects (odds ratio, 1.00; 95% confidence interval, 0.64-1.56; P = 1.00) had died; only 57% of the control subjects had received renal-replacement therapy. Between-group survivors' Day-60, Day-90, intensive care unit, and in-hospital mortality rates, Day-30 ventilator-free days, and renal function recovery were comparable. HVHF patients experienced faster correction of metabolic acidosis and tended to be more rapidly weaned off catecholamines but had more frequent hypophosphatemia, metabolic alkalosis, and thrombocytopenia. CONCLUSIONS: For patients with post-cardiac surgery shock requiring high-dose catecholamines, the early HVHF onset for 48 hours, followed by standard volume until resolution of shock and recovery of renal function, did not lower Day-30 mortality and did not impact other important patient-centered outcomes compared with a conservative strategy with delayed CVVHDF initiation only for patients with persistent, severe acute kidney injury. Clinical trial registered with www.clinicaltrials.gov (NCT 01077349)

    Effect of Xenon Anesthesia Compared to Sevoflurane and Total Intravenous Anesthesia for Coronary Artery Bypass Graft Surgery on Postoperative Cardiac Troponin Release: An International, Multicenter, Phase 3, Single-blinded, Randomized Noninferiority Trial

    No full text
    BACKGROUND: Ischemic myocardial damage accompanying coronary artery bypass graft surgery remains a clinical challenge. We investigated whether xenon anesthesia could limit myocardial damage in coronary artery bypass graft surgery patients, as has been reported for animal ischemia models. METHODS: In 17 university hospitals in France, Germany, Italy, and The Netherlands, low-risk elective, on-pump coronary artery bypass graft surgery patients were randomized to receive xenon, sevoflurane, or propofol-based total intravenous anesthesia for anesthesia maintenance. The primary outcome was the cardiac troponin I concentration in the blood 24 h postsurgery. The noninferiority margin for the mean difference in cardiac troponin I release between the xenon and sevoflurane groups was less than 0.15 ng/ml. Secondary outcomes were the safety and feasibility of xenon anesthesia. RESULTS: The first patient included at each center received xenon anesthesia for practical reasons. For all other patients, anesthesia maintenance was randomized (intention-to-treat: n = 492; per-protocol/without major protocol deviation: n = 446). Median 24-h postoperative cardiac troponin I concentrations (ng/ml [interquartile range]) were 1.14 [0.76 to 2.10] with xenon, 1.30 [0.78 to 2.67] with sevoflurane, and 1.48 [0.94 to 2.78] with total intravenous anesthesia [per-protocol]). The mean difference in cardiac troponin I release between xenon and sevoflurane was -0.09 ng/ml (95% CI, -0.30 to 0.11; per-protocol: P = 0.02). Postoperative cardiac troponin I release was significantly less with xenon than with total intravenous anesthesia (intention-to-treat: P = 0.05; per-protocol: P = 0.02). Perioperative variables and postoperative outcomes were comparable across all groups, with no safety concerns. CONCLUSIONS: In postoperative cardiac troponin I release, xenon was noninferior to sevoflurane in low-risk, on-pump coronary artery bypass graft surgery patients. Only with xenon was cardiac troponin I release less than with total intravenous anesthesia. Xenon anesthesia appeared safe and feasible
    corecore