OPTICAL AND SPECTROSCOPIC PROPERTIES OF Er3+DOPED 60Sb2O3-10Na2O-30PbO GLASS

Er3+doped sodium lead antimonite glass have been prepared and analyzed by (UV-Vis-NIR) absorption, near infrared luminescence and fluorescence decays. The optical band gap and refractive index were calculated from the (UV-Vis-NIR) absorption. The Judd-Ofelt theory has been applied to compute the J–O intensity parameters Ωt (t= 2, 4, 6) from absorption spectrum and determine the spectroscopic parameters such as the radiative transition probability (Arad), radiation lifetime (τ) and branching ratio (β) of Er3+ transition. Experimental lifetime of the glass for the transition between 4I13/2 and 4I15/2   level was calculated from the photoluminescence decay curves and estimated the quantum efficiency. Absorption, emission and gain cross-section, effective band width (Δλeff) and gain band width of the 4I13/2 ®4I15/2   transition of Er3+ in glass are recorded and calculated. The obtained results confirm the potential of this glass in signal amplification and laser application

Optical properties of alkali-antimonite glasses and purified processes for fiber drawing

International audienceWe study Antimonite glasses in the ternary systems Sb2O3-PbO-M2O (M = Li, Na, K). We have measured the density and refractive index according to the glass composition in this system. We have also measured the optical transmission in the UV-Vis and infrared range and the optical band gap. The influence of glass synthesis on extrinsic absorption has been studied. For the first time in this system, we have observed that stable glassy composition was drawn into a fiber, and the optical losses were determined in the 1-5 μm infrared region

OPTICAL ABSORPTION AND JUDD-OFELT OF Pr3+ DOPED ANTIMONY BASED GLASSES

Glass with the composition 79.75Sb2O3-10Li2O-10WO3-0.25PrF3 (mol%) were synthesized employing melt quenching technique. Visible and near infrared absorption spectra were measured the Judd–Ofelt (J-O) parameters Ω2, Ω4 and Ω6, were determined for Pr3+ ions using the absorption bands and calculate the oscillator strengths, these parameters are used to calculated various radiative properties of different Pr3+ transitions

Artificial neural network analysis of optical measurements of glasses based on Sb2O3

In the paper we present application of artificial neural network (ANN) on relation between glass composition versus optical transmittance of the chosen glass systems of Sb2O3 - PbCl2 and Sb2O3 – PbO – M2O, where M was Na, K and Li, respectively. The excellent prediction ability of special ANN program developed for this study demonstrates the possibility to influence the glass composition to obtain asked optical properties. The measurements of the temperature dependencies of the direct electric conductivity show the strong influence of the concentration of the individual glass compounds of systems Sb2O3 - PbCl2 and Sb2O3 – PbO – M2O (M is Na, K, Li) on their electric and dielectric properties. Glasses own the same mechanism of the electric conductivity with activation energy, which goes to the value 3.75 eV when temperature is higher than 250 C. Similarly optical transmittance T of systems Sb2O3 - PbCl2 and Sb2O3 – PbO – M2O strongly depends on the glass composition and the amount of defects, too. The glass 70Sb2O3 – 30PbCl2 reached the highest value of T. The minimal content of defects in its volume makes these glasses very perspective for next searching. The measurements of the complex modulus M of mentioned glasses showed their high sensitivity to the changes of glass structure connected with the creation of different sort and the amount of defects. The sensibility of the used methods is comparable with the usual exploited methods (X-ray analysis, optical microscopy) and makes possible to assess partially the quantitative occurrence of defects in the glass volume. A model of neural network for prediction of the optical transmittance was created. Model enables to predict the transmittance with sufficiently small error. After evaluation of results we can state that exploitation of neural networks is advantageous, if it is necessary to express complex mutual relations among sensor-based data. Neural networks are able to realize and appropriately express general properties of data and relations among them and on the contrary to suppress relationships which occur sporadically or they are not sufficiently reliable and strong. Their usage enables retrieval of relationships among parameters of the process which with use of common methods are not possible to trace for reason of their mutual interactions, big amount and dynamics. Use of a neural network seems to be suitable tool for estimating different important optical parameters.Web of Science183-424724

Abstracts of the First International Conference on Advances in Electrical and Computer Engineering 2023

This book presents extended abstracts of the selected contributions to the First International Conference on Advances in Electrical and Computer Engineering (ICAECE'2023), held on 15-16 May 2023 by the Faculty of Science and Technology, Department of Electrical Engineering, University of Echahid Cheikh Larbi Tebessi, Tebessa-Algeria. ICAECE'2023 was delivered in-person and virtually and was open for researchers, engineers, academics, and industrial professionals from around the world interested in new trends and advances in current topics of Electrical and Computer Engineering. Conference Title: First International Conference on Advances in Electrical and Computer Engineering 2023Conference Acronym: ICAECE'2023Conference Date: 15-16 May 2023Conference Venue: University of Echahid Cheikh Larbi Tebessi, Tebessa-AlgeriaConference Organizer: Faculty of Science and Technology, Department of Electrical Engineering, University of Echahid Cheikh Larbi Tebessi, Tebessa-Algeri

Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients

International audienceThe aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed