Publications Scientifiques
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Item Annealing effect on copper-doped sodo-borate glasses (na2o-4b2o3)(2023) Aboutaleb, Djamila; Safi, BrahimThe annealing effect of an alkalino-borate type glass below the softening temperature was investigated accord ing to the Na2O-B2O3 binary system. Doping of the samples was done by the introduction of copper oxide "CuO" according to different levels. The properties of elaborate glasses before and after annealing have been studied. DRX diffraction, optical spectroscopy and infrared analysis were used to complete this study. The obtained results show that the annealing heat treatment affects the structure of these glasses by redistributing the structural units, partially correcting the defects and reinforcing them of the structure. It has been noticed that the BO3 units are reformed again and the BO4 have decreased, which has led to an increase in the coefficient of thermal expansion, a decrease in the diffraction index and optical dispersion, a drop in mechanical prop erties, thermal conductivity and electrical permittivity.Item Preparation And Characterization Of B2o3- Bao-al2o3 (bba) Glass System(Research Unit Materials, Processes and Environment/Faculty of Science and Engineering, Boumerdes University, Boumerdes, Algeria, 2013) Aboutaleb, Djamila; Safi, B.; Benhaoua, F.n borateglasses, the main structural units are the [BO3] triangles and [BO4] tetradral which form different superstructural units like; boroxol rings, metaborate rings and chains, pentaborate, diborate, triborate and pyroborate. In this work, the Barium aluminoborate glasses were prepared. Some of properties were investigated by measure like density and chemical durability and the other by calculs. The dilatometric curves were determined and they revealed that the temperature of transition (Tg) and softening (Ts) and the dilatation coefficient increase by addition of Al2O3and BaO content.Item Séparation Des Phases Dans Le Système sio2- B2O3- Na2O (ISBN)(2009) Aboutaleb, Djamila; Iratni, A.; Safi, Brahim; Douglad, J.Item Ostwald Ripening Phenomena in B2O3-PbO Glass System(2009) Aboutaleb, Djamila; Iratni, Aicha; Safi, BrahimLead borate glass was prepared by the quench method, followed by treatment at its isothermal temperature at different time periods. When the sample was rapidly cooled from the melt, it showed two distinguished opalescent layers. The SEM analysis and XRD pattern provide characteristics of glass without XRD peaks and their morphology show the aggregated spherical particles in the phase separated glass. This data show that phase separation occurred even when the melts were rapidly cooled. However, the sample shows a Ostwald ripen with increasing time of heat treatment, which implies that the size of particles increases and their number decreases. The infrared absorption spectra show shift edge for sample glass with heat treatment, which indicates a change of structural configuration, i.e. conversion of tetrahedral boron on triangular boron coordinationItem Simulation of immiscibility regions in sodium borosilicate glasses(2014) Aboutaleb, Djamila; Safi, BrahimIn this paper, sodium borosilicates glasses were prepared by melting in air. These heat-resistant transparent glasses have subjected subsequently isothermal treatments at different times, which have transformed them at opaque glass (milky white color). Such changes indicate that these glasses showed clearly phase separation (immiscibility). The immiscibility region in a sodium borosilicate ternary system was investigated in this work, ie to determine the regions from which some compositions can show phase separation. For this we went through the conditions of thermodynamic equilibrium, which were translated later by mathematical equations to find an approximate solution. The latter has been translated in a simulation which was established thereafter to find the immiscibility regions in this type of special glassesItem Performance of Self-Compacting mortars containing foam glass granulate(2015) Safi, Brahim; Aboutaleb, Djamila; Saidi, Mohammed; Benmounah, Abdelbaki; Benbrahim, FahimaItem Use of refractory bricks as sand replacement in self-compacting mortar(Taylor & Francis Online, 2017) Aboutaleb, Djamila; Safi, Brahim; Chahour, Kahina; Belaid, AmraneThis present work investigate the possibility of using refractory bricks (RB) as fine aggregates (by partial and total substitution of natural sand) in self-compacting mortars (SMCs). For this, an experimental study was carried out to evaluate physical and mechanical properties ((bulk density, compressive and flexural strength) of the self-compacting mortars (SCMs) with partial and total substitution of natural sand (NS) by crushed refractory bricks (RB) at different ratio (BR/S= 0, 10, 30, 50 et 100%) by weight. The results obtained show that the RB (0/5 mm class), can be used as fine aggregates for self-compacting mortar, without affecting the essential properties of mortar. However, the performances of RB-based mortar (100% as sand), were better and are suitable for a fluid concrete (such as self- compacting concrete)Item Granulated foam glass based on mineral wastes used for building materials(SAGE, 2017) Chahour, Kahina; Aboutaleb, Djamila; Safi, Brahim; Mazari, Tassadit; Zeghad, MohamedItem Lithium oxide effect on the thermal and physical properties of the ternary system glasses (Li2O3-B2O3-Al2O3)(2015) Aboutaleb, Djamila; Safi, BrahimThe borate glasses are known by their structural characterized by existence of unit’s structural composed by triangles and tetrahedrons boron in different configurations depending on the percentage of B2O3 in the glass chemical composition. In this paper, effect of lithium oxide addition on the thermal and physical properties of an alumina borate glass, was investigated. It was found that the boron abnormality has a significant effect in the change of glass properties according to the addition rate of lithium oxideItem Effect of calcined silt on the rheological behavior of cement pastes of the self compacting concrete SCC(European Journals Inc, 2010) Safi, Brahim; Benmounah, Abdelbaki; Saidi, Mohammad Said; Aboutaleb, Djamila