Mokhtar A.,University Doran1 Ahmed Ben Bella |
Djelad A.,University Doran1 Ahmed Ben Bella |
Boudia A.,University Doran1 Ahmed Ben Bella |
Sassi M.,University Doran1 Ahmed Ben Bella |
Bengueddach A.,University Doran1 Ahmed Ben Bella
Journal of Porous Materials | Year: 2017
The purpose of this work is the synthesis of two series of layered silicate materials with different ratios (10, 30, 50, 80 and 100) of Cu(NO3)2, or Zn(NO3)2 by ion-exchange method. Several analysis techniques have been used such as X-ray diffraction, energy dispersive X-ray spectroscopy, thermogravimetric analysis, scanning electron microscope and Fourier transform infrared spectroscopy. The results revealed that ion-exchange method of copper and zinc with different ratios did not affect the structure of Na-magadiite. The gap between the theoretical and experimental ion-exchange are in agreement. Antibacterial activity test against Escherichia coli, Rhizobium sp. and Staphylococcus demonstrate that when ratio was (30, 50, 80 and 100) the antibacterial activity of the layered silicate materials showed high antibacterial activity. © 2017 Springer Science+Business Media New York
Hadj Mokhtar H.,University of Oran 1 |
Boukoussa B.,University dOran1 Ahmed Ben Bella |
Boukoussa B.,Center University Ain Temouchent |
Hamacha R.,University dOran1 Ahmed Ben Bella |
And 2 more authors.
RSC Advances | Year: 2015
This paper focuses on the use of natural sources for the preparation of efficient and low cost catalysts. CaCO3 is obtained from cuttlefish bone and was modified by the cation exchange of Ca2+ by Cu2+ in CaCO3 using solutions of copper (Cu(NO3)2) at different concentrations. The modification of the solids was investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and ultraviolet-visible (UV-vis) spectroscopy. The results show that the copper exchanged materials contain a CuCO3-CuO nanoparticle composite. The obtained solids were used as catalysts for the cycloaddition reaction of different azides with activated alkenes at room temperature under liquid phase conditions. The different parameters which affect the reaction were investigated such as reaction time, temperature of the reaction, effect of the copper content, catalyst mass, effect of the solvent and nature of the azide. High yields were obtained when the catalyst contained more copper. The best catalysts were calcined at different temperatures (200, 300, 400, 500 °C) in order to determine whether the active phase was CuCO3 or CuO in the catalytic reaction. The XRD analysis of the calcined composites shows that an increase in calcination temperature leads to the formation of the CuO phase. On the other hand, the use of these calcined materials as catalysts shows that the active phase is copper carbonate. Finally, a new method for preparing triazoles with short reaction times was developed by the use of a cheap environmentally friendly catalyst. © 2015 The Royal Society of Chemistry.
Bendeddouche C.K.,University dOran1 Ahmed Ben Bella |
Adjdir M.,University dOran1 Ahmed Ben Bella |
Adjdir M.,Institute of Functional Interfaces |
Benhaoua H.,University dOran1 Ahmed Ben Bella
Letters in Organic Chemistry | Year: 2016
Background: The cyclopropanation reaction was inspected by addition of carbene generated from ethyl diazoacetate in the presence of a greener Cu-exchanged bentonite catalyst to olefin under solvent free condition. The cyclopropanes were obtained with good yields. Our own contribution in this area was to introduce a modified Algerian bentonite as a catalyst and microwave activation as a mode of heating. Methods: A catalytic material developed from natural type montmorillonite clays, from deposits of Maghnia (Western Algeria), by cation exchange (Cu2+) was characterized by different spectral methods. The catalytic properties of the new material were explored in cyclopropanation reaction of olefins under microwave irradiation. A comparative study with Cu-exchanged bentonite as catalyst between microwave activation and classical heating was conducted. Results: Cu2+ exchanged clay is an efficient catalyst in the generation of carbenes from diazocompounds, under microwave irradiation. The formation of carboxylate cyclopropane was performed in solvent free condition with moderate diastereoselectivity. The yields were good, and the catalyst can be reused at least three times without noticeable loss of catalytic activity. Conclusion: This work shows that the coupling "modified clay/microwave activation" is a clean and simple access to functionalized cyclopropanes. This reusable Cu exchanged clay material is shown to be as a good substitute for many sophisticated and hardly accessible catalysts. © 2016 Bentham Science Publishers.
Abdelouhab F.Z.,University Doran1 Ahmed Ben Bella |
Atmani B.,University Doran1 Ahmed Ben Bella
Journal of Decision Systems | Year: 2016
Les ontologies deviennent, de plus en plus, des modèles de représentation et de stockage d'informations très efficaces facilitant le traitement et la gestion des connaissances à travers les techniques de l’intelligence artificielle et offrant le potentiel d'assemblage d'une grande quantité d'informations à travers ce qu'on appelle «la fusion d'ontologies». Cette dernière se voit de plus en plus importante et fréquente dans les recherches actuelles vu l’apport qu’elle offre à construire, à moindre coût, des ontologies génériques à partir des ontologies partielles et à les adapter aux nouvelles exigences des besoins évolutifs des connaissances. Cependant, elle définit l’interprétation d’un véritable réseau de connaissances dont la complexité se heurte à une explosion du nombre et de la taille des ontologies à fusionner. D’un autre coté les automates cellulaires sont un modèle particulier de systèmes dynamiques discrets remarquables par leurs simplicités et leurs capacités à produire des comportements d’une grande richesse. La contribution adressée dans ce papier est de concevoir une nouvelle approche de fusion booléenne des ontologies en utilisant la machine cellulaire CASI (Cellular Automata for Symbolic Induction) permettant d’optimiser la complexité des algorithmes de fusion classiques par des fonctions simples de transitions locales synchrones. © 2016 Informa UK Limited, trading as Taylor & Francis Group
Bensenane B.,CNRS Hubert Curien Multi-disciplinary Institute |
Bensenane B.,University dOran1 Ahmed Ben Bella |
Asfari Z.,CNRS Hubert Curien Multi-disciplinary Institute |
Platas-Iglesias C.,University of La Coruña |
And 4 more authors.
Dalton Transactions | Year: 2016
The syntheses of two new ligands based on a calixarene scaffold in the cone conformation functionalized on the phenolic positions 1 and 3 by diethylthiophosphonates (L1) or tetra(tri)thioethyleneglycol (L2) crowns are described. Together with ligand L3, the parent calixarene substituted by a penta(tetra)thioethyleneglycol crown, the spectroscopic properties of the ligands were determined by means of UV-Vis absorption spectroscopy and steady-state and time-resolved fluorescence spectroscopy, showing that the ligands display modest but non-negligible intrinsic fluorescence properties (πfluo = 0.023; 0.026 and 0.029 for L1, L2 and L3 in CH2Cl2, respectively). The X-ray crystal structures of ligand L1, and of its synthetic precursor were determined and analyzed for their capacity to accommodate the incoming cationic species. The ligands were further investigated for their complexation properties of divalent cations such as Cu2+, Zn2+, Hg2+ and Cd2+ (under their nitrate salts) in 1:1 CH3CN/CH2Cl2 solutions (I = 0.01 M Et4NNO3, T = 25.0(2) °C), in which the additions of cations were monitored by absorption and steady-state fluorescence spectrophotometries. The stoichiometries of the corresponding complexes were assessed by ESI-MS, while insights into the structures of the complexes in solution were obtained with density functional theory (DFT) calculations. The influence of the sulphur and phenol coordinating moieties was addressed to show that the thiocrown compounds L2 and L3 displayed a marked affinity towards the soft mercuric cation (Δlog K ≥ 2), with no particular size selectivity effect, whereas ligand L1 can accommodate both the thio and phenol units to coordinate with Cu(ii). Altogether, these results point to the use of L3 as a selective fluoroionophore for detection of Hg2+. © 2016 The Royal Society of Chemistry.