Time filter

Source Type

El Oued, Algeria

Bentouila O.,University of Ouargla | Bentouila O.,University of Rennes 1 | Aiadi K.E.,University of Ouargla | Rehouma F.,University dEl Oued | Poulain M.,University of Rennes 1
Journal of Optoelectronics and Advanced Materials

New series of rare earth doped halogeno-phosphate glasses with compositions: (100-x-y) NaPO3 - x PbCl2- y BaCl 2: LnF3 (Ln=Er or Ho) were prepared and characterized. These glasses exhibit a good resistance against devitrification. Spectroscopic analyses based on Judd-Ofelt theory were performed. Starting from absorption spectra, the oscillator strengths and the intensity parameters Ω2, Ω4 and Ω6 have been evaluated, and various radiative properties like radiative transition probability, branching ratio and radiative lifetime were determinated. Spectroscopic quality factor (Ω4 /Ω6) has been evaluated to understand the lasing efficiency of these materials. These glasses could be used as lasing materials and offer prospects for photonics applications. Source

Mazidi S.,Center de Recherche Nucleaire de Draria | Meftah B.,Center de Recherche Nucleaire de Draria | Belgaid M.,University of Science and Technology Houari Boumediene | Letaim F.,University dEl Oued | Halilou A.,Center de Recherche Nucleaire de Draria
Nuclear Engineering and Design

This paper introduces the Integrated Thermal Hydraulic and Neutronic Analyzer SYStem (ITHNA.SYS) that has been developed for the Algerian research reactor NUR. It is used both as an operating aid tool and as a core physics engineering analysis tool. The system embeds three modules of the MTR-PC software package developed by INVAP SE: the cell calculation code WIMSD, the core calculation code CITVAP and the program TERMIC for thermal hydraulic analysis of a material testing reactor (MTR) core in forced convection. ITHNA.SYS operates both in on-line and off-line modes. In the on-line mode, the system is linked, via the computer parallel port, to the data acquisition console of the reactor control room and allows a real time monitoring of major physical and safety parameters of the NUR core. PC-based ITHNA.SYS provides a viable and convenient way of using an accumulated and often complex reactor physics stock of knowledge and frees the user from the intricacy of adequate reactor core modeling. This guaranties an accurate, though rapid, determination of a variety of neutronic and thermal hydraulic parameters of importance for the operation and safety analysis of the NUR research reactor. Instead of the several hours usually required, the processing time for the determination of such parameters is now reduced to few seconds. Validation of the system was performed with respect to experimental measurements and to calculations using reference codes. ITHNA.SYS can be easily adapted to accommodate other kinds of MTR reactors © 2015 Elsevier B.V. All rights reserved. Source

Mahfoudi N.,University Mohamed Khider of Biskra | Khachkouch A.,University dEl Oued | Moummi A.,University Mohamed Khider of Biskra | Benhaoua B.,University dEl Oued | El Ganaoui M.,University of Lorraine
Mechanics and Industry

This paper deals with the experimental investigation of transient behavior and thermal storage capability of a sensible heat storage unit. The former is designed to store solar energy by using sand as a storage medium. A cubic unit has been designed employing three configurations of embedded charging tubes to study the performances of the system. The storage material used in this experimentation (sand) has been characterized by its, grain size, density, and heat capacity. Performances of the thermal storage bed (including charging time, energy stored rate, charging energy efficiency) have been evaluated for selecting the storage material. From our experiments, we found that the number of charging tubes affects significantly the storage performances. © AFM, EDP Sciences 2015. Source

Lanez T.,University dEl Oued | Henni M.,University dEl Oued
Journal of the Iranian Chemical Society

Cyclic voltammetry was used to explore the interaction of (ferrocenylmethylamino) benzonitrile (FMAB) with superoxide anion radical (O2.-), electrochemically generated by the reduction in commercial molecular oxygen in acetonitrile. The difference in the electrochemical behavior of O2.- in the absence and presence of FMAB, including shifts in peak potential and decrease in anodic peak current, was successfully investigated for the determination of interaction parameters such as the binding constant, ratio of binding constants, binding free energy and mode of interaction. The anodic peak potential shifts and the magnitude of binding free energy ΔG suggest the electrostatic interaction of O2.- with FMAB as the dominant mode, whereas the negative sign of ΔG indicates the spontaneity of the interaction. The antioxidant activity of FMAB derivatives was also evaluated using spectrophotometrical and electrochemical techniques. The spectrophotometrical assays were carried out using 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH), while the electrochemical assays were determined by measuring the oxidation peak current of O2.-. The activity was found to be highest for 3FMAB in both DPPH and O2.- radicals scavenging methods (0.0183) and (0.0090 mg/mL), respectively, which is equal to half the antioxidant activity of standard antioxidant ascorbic acid (0.0117) and (0.0041 mg/mL). © 2016, Iranian Chemical Society. Source

Boubekri C.,University dEl Oued | Lanez T.,University dEl Oued | Djouadi A.,University dEl Oued
Scientific Study and Research: Chemistry and Chemical Engineering, Biotechnology, Food Industry

Total phenolic content and antioxidant activity were measured in the whole fruit of dark-purple eggplant cultivars from five different regions of east Algeria using, respectively, the Folin-Ciocalteu method, spectrophotometrical and electrochemical assays. Total phenolic contents were highest in sample from Jijel, followed by Skikda cultivars, finally sample from Guelma with the lowest phenolic contents. Total phenolic content was positively associated with total antioxidant activity in eggplant extracts. These results demonstrate that phenolic compounds have a significant contribution to the total antioxidant activity, which varies considerably depending on the region of the fruit cultivar analyzed. Antioxidant activity was highly correlated with total phenolic contents (R2 = 0.714). © 2015 ALMA MATER Publishing House, “VASILE ALECSANDRI” University of Bacău. All rights reserved. Source

Discover hidden collaborations