Publications Internationales
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Item Effect of crystallization time on the structure of the Aluminosilicate glass-ceramic(IOP Publishing Ltd, 2018) Souag, Rafika; Nidal, Kamel; Moudir, Dalila; Mouheb, Yasmina; Kamariz, S.All This study deals with the influence of the time of crystallization on the structure of an aluminosilicate glass-ceramic ceramized by a nucleation –crystallization treatment at 790°C for 2 h, and 900°C, for different periods of time ranging from 2 to 12 h. For the whole of the materials, Archimedes density is between 2441-2578 kg/m3. Both X-ray diffraction and scanning electron microscopy analyses reveal two main crystalline phases for the whole of the heating treatments, namely spodumen and leucite. These phases grow regularly with the crystallization time. In addition, aqueous stability testing was carried out using the standard MCC-2 static leach test method at 90 °C and V(ml) = 30 S(cm2) for a series of five test durations - 7, 14, 28, 35 and 42 days. The X-ray fluorescence analytical technique was used to determine the concentration of lanthanum (La) and molybdenum (Mo) leached in our material. The dissolution parameters, in this case the normalized elemental mass loss (NL) and the leaching rate (τ) of each element, were determined from these concentrations. The results demonstrate that The leaching tests showed that the material is stable and it stabilizes at low values (2.5 10−9Kg/m2) for La when the ceramization time does not exceed 4h beyond this, Leaching equilibrium and the passivation phase is broken. For Mo and for all glass ceramics at different times of crystallization, the equilibrium reaches (3.15 10-8 Kg/m2j) and the passivation layer is formed. The glass ceramics at different time of cristallization presently studied appears to have a good chemical durability.Item Study of phase changes in aromatic polyesters induced by the effect of rubbery annealing(Taylor & Francis, 2012) Khemici, Wafik Mohammed; Doulache, N.; Rahmani, B.; Gourari, A.Item Elaboration and characterization of tubular supports for membranes filtration(Taylor & Francis, 2016) Guechi, A.; Harabi, A.; Condoum, S.; Zenikheri, F.; Boudaira, B.; Bouzerara, F.; Foughali, L.Item Aluminium-induced crystallization of amorphous silicon films deposited by DC magnetron sputtering on glasses(2011) Kezzoula, F.; Hammouda, A.; Kechouane, M.; Simon, p.; Abaidia, Seddik-El-Hak; Keffous, A.; Cherfi, R.; Menari, H.; Manseri, A.Amorphous silicon (a-Si) and hydrogenated amorphous silicon (a-Si:H) films were deposited by DC magnetron sputtering technique with argon and hydrogen plasma mixture on Al deposited by thermal evaporation on glass substrates. The a-Si/Al and a-Si:H/Al thin films were annealed at different temperatures ranging from 250 to 550 °C during 4 h in vacuum-sealed bulb. The effects of annealing temperature on optical, structural and morphological properties of as-grown as well as the vacuum-annealed a-Si/Al and a-Si:H/Al thin films are presented in this contribution. The averaged transmittance of a-Si:H/Al film increases upon increasing the annealing temperature. XRD measurements clearly evidence that crystallization is initiated at 450 °C. The number and intensity of diffraction peaks appearing in the diffraction patterns are more important in a-Si:H/Al than that in a-Si/Al layers. Results show that a-Si:H films deposited on Al/glass crystallize above 450 °C and present better crystallization than the a-Si layers. The presence of hydrogen induces an improvement of structural properties of poly-Si prepared by aluminium-induced crystallization (AIC)