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1.
Manal Benyoussef Moneim Zannen Jamal Belhadi Bouchaib Manoun Jean-Luc Dellis Mimoun El Marssi Abdelilah Lahmar 《Ceramics International》2018,44(16):19451-19460
In this work, Na0.5(Bi1-xDyx)0.5TiO3 (0?≤?x?≤?15%) ceramics were prepared via solid state reaction method and were characterized. A stable and pure perovskite phase was revealed by X-ray diffraction analysis for all compositions and a symmetry change from rhombohedral to orthorhombic phase was detected beyond 10% of Dy substitution. The incorporation of Dy3+ into Sodium Bismuth Titanate (Na0.5Bi0.5TiO3) matrix allows a substantial decrease of the coercive field, an increase in the resistivity, and leads to a high stability of the dielectric permittivity (??/?(150?°C) ≤?±?15%) over a wide temperature range. Furthermore, this system was found to exhibit improved energy storage properties at high temperatures with a maximum energy density of 1.2?J/cm3 obtained for 2%Dy composition at 200?°C. The obtained results are very promising for energy storage capacitors operating at high temperatures. 相似文献
2.
Haddaji Younesse Hamdane Hasna Majdoubi Hicham Mansouri Said Allaoui Driss El bouchti Mehdi Tamraoui Youssef Manoun Bouchaib Oumam Mina Hannache Hassan 《SILICON》2021,13(7):2389-2400
Silicon - Geopolymers produced with metakaolin (MK) and thermally untreated phosphate sludge (PS) are beneficial and environmentally advantageous materials, but their fragility limits its... 相似文献
3.
Performance of a compact submerged membrane sequencing batch reactor (SM-SBR) for greywater treatment 总被引:1,自引:0,他引:1
A long-term study was carried out to evaluate the performance of submerged membrane sequencing batch reactors (SM-SBR) for greywater treatment. Three pilot plants were operated in three different countries with distinct wastewaters to prove that treated greywater can be used for reuse purposes.In all plants the permeate quality fulfilled in most cases the high mandatory values of different European directives. Membrane permeability declined significantly within a period of three to four months so that recovery cleanings were necessary 3 to 4 times a year. In general, the treated greywater from an SM-SBR can be reused for irrigation or cleaning purposes. SM-SBR for greywater treatment are especially interesting in cases of space limitations where the small footprint of the system can outweigh inconveniences like frequent chemical cleanings. 相似文献
4.
Omar Bouattane Bouchaib Cherradi Mohamed Youssfi Mohamed O. Bensalah 《Parallel Computing》2011,37(4-5):230-243
In this paper, we propose a parallel algorithm for data classification, and its application for Magnetic Resonance Images (MRI) segmentation. The studied classification method is the well-known c-means method. The use of the parallel architecture in the classification domain is introduced in order to improve the complexities of the corresponding algorithms, so that they will be considered as a pre-processing procedure. The proposed algorithm is assigned to be implemented on a parallel machine, which is the reconfigurable mesh computer (RMC). The image of size (m × n) to be processed must be stored on the RMC of the same size, one pixel per processing element (PE). 相似文献
5.
Ait Ali Noureddine Cherradi Bouchaib El Abbassi Ahmed Bouattane Omar Youssfi Mohamed 《Multimedia Tools and Applications》2018,77(16):21221-21243
Multimedia Tools and Applications - Image segmentation in the medical imagery such as MRI, is an essential step to the sensitive analysis of human tissues lesions with the objective to improve the... 相似文献
6.
Soufiane Bahou Hicham Labrim Marwan Lakhal Mohamed Bhihi Bouchaib Hartiti Hamid Ez-Zahraouy 《International Journal of Hydrogen Energy》2021,46(2):2322-2329
Performing an ab initio analysis, we inspect the effect of magnesium vacancies and hydrogen doping on the magnesium hydride (MgH2). The Korringa – Kohn – Rostoker method integrated with the coherent potential approximation is used to perform our calculations. In particular, we find that the gravimetric capacity of MgH2 increases from 7.658 to 9.816 wt% when the concentrations of magnesium vacancies and hydrogen dopant atoms increase from 0 to 10%. Concretely, the results reveal that the magnesium vacancies and the hydrogen doping have a beneficial effect on the hydrogen storage properties of the hydride by decreasing its desorption temperature and stability. This decrease can be explained on the one hand by the diminution of the number of Mg atoms that establish strong bonds with H atoms, and on the other hand by using the density of states, which indicates that when the concentrations increase, the Mg and H states shift to the conduction band. We also obtain that the value of the desorption temperature can be controlled by varying the concentrations of magnesium vacancies and hydrogen dopant atoms from 4.2 to 5.8% in order to reach the optimum range 289–393 K for the practical use of fuel cell vehicles. 相似文献
7.
World Wide Web (WWW)-based electronic commerce has emerged as a mean to conduct business transactions that were previously
handled through traditional interorganizational systems, phone, fax, on-site visits, or mail. Today, electronic procurement
(e-procurement) accounts for most of the volume and value of the business transactions conducted over the Internet. As of
yet, however, little or no research has assessed the functional and non-functional requirements sought for the WWW-based systems
used to support the procurement process. This paper, presents findings of a survey of 133 corporate buyers from about 130
companies on the use of readily available web-based systems for business-to-business transactions and the requirements perceived
to be critical to the effective support of supply chain operations. 相似文献
8.
Fatima El Bachraoui Zakaria Chchiyai Youssef Tamraoui Hassan El Moussaoui Jones Alami Bouchaib Manoun 《中国稀土学报(英文版)》2022,40(4):652-659
Structural, optical and magnetic properties are reported for new synthesized perovskite materials. Ba0.3La0.7Ti0.3Fe0.7O3 and Ba0.1La0.9Ti0.1Fe0.9O3 compositions were prepared via solid state reaction. X-ray analysis confirms that both compositions show feature of perovskite structure. Rietveld refinement method was used to confirm the phase formation and investigate the structure and space group. The study demonstrates the formation of orthorhombic structure with Pnma space group for Ba0.3La0.7Ti0.3Fe0.7O3 while the composition Ba0.1La0.9Ti0.1Fe0.9O3 structure adopts Pbnm symmetry. UV–vis spectroscopy measurements show very broad and intense UV–visible light absorption, the estimated band gap ranges between 2.07 and 2.15 eV. Magnetic measurements were carried out for the compositions Ba0.3La0.7Ti0.3Fe0.7O3 and Ba0.1La0.9Ti0.1Fe0.9O3. The hysteresis loops of both samples at 300 and 10 K show a strong ferromagnetic behavior. The temperature dependent magnetization at 0.05 T under field-cooled (FC) and zero field cooled (ZFC) modes shows magnetic frustration or spin glass-like behavior. 相似文献
9.
Thierno Sall A. Nafidi Bernab Mar Soucase Miguel Mollar Bouchaib Hartitti Mounir Fahoume 《半导体学报》2014,35(6):063002-5
Indium sulfide (InzS3) thin films were prepared by chemical spray pyrolysis technique from solutions with different [S]/[In] ratios on glass substrates at a constant temperature of 250 ~C. Thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy disper- sive X-ray spectroscopy (EDS), Raman spectroscopy and optical transmittance spectroscopy. All samples exhibit a polycrystalline structure with a preferential orientation along (0, 0, 12). A good stoichiometry was attained for all samples. The morphology of thin film surfaces, as seen by SEM, was dense and no cracks or pinholes were ob- served. Raman spectroscopy analysis shows active modes belonging to j3-1naS3 phase. The optical transmittance in the visible range is higher than 60% and the band gap energy slightly increases with the sulfur to indium ratio, attaining a value of 2.63 eV for [S]/[In] : 4.5. 相似文献
10.
Ali Noureddine Ait abbassi Ahmed El Cherradi Bouchaib 《The Journal of supercomputing》2022,78(2):1583-1601
The Journal of Supercomputing - Fuzzy C-mean (FCM) is an algorithm for data segmentation and classification, robust and very popular within the scientific community. It is used in several fields... 相似文献