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Das D.,Dinhata College | Messaadi A.,Tunis el Manar University | Dhouibi N.,Tunis el Manar University | Ouerfelli N.,Tunis el Manar University | Hamzaoui A.H.,Center National des Recherche en science des Materiaux
Physics and Chemistry of Liquids | Year: 2013

Calculation of excess properties in N,N-dimethylacetamide + water binary mixtures at (298.15, 308.15 and 318.15) K from experimental density, viscosity and sound velocity values were presented in previous work. Applications of these experimental values to test different correlation equations as well as their corresponding relative functions were also reported. Considering the quasi-equality between the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ΔH*, here we can define partial molar activation energy Ea 1 and Ea 2 for N,N-dimethylacetamide and water respectively along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all the domains of composition shows the existence of two main distinct behaviours separated by a stabilised structure in a short range of mole fraction in N,N-dimethylacetamide from 0.2 to 0.3. We add that correlation reveals interesting Arrhenius temperature which is closely related to the vapourisation temperature in the liquid vapour equilibrium. © 2013 Taylor and Francis Group, LLC.


Marzougui H.,University of Carthage | Attia-Essaies S.,University of Carthage | Attia-Essaies S.,Center National des Recherche en science des Materiaux | Ben Hassen-Chehimi D.,University of Carthage
Journal of Molecular Structure | Year: 2016

Tutton's salts K2M(SO4)2·6H2O (M = Mg, Ni) have been synthesized by the slow evaporation method at room temperature. A complete structural characterization has been carried out by means of powder X-ray diffraction (XRD). The results indicate that the structure of these salts is monoclinic system with the space group P21/a (Z = 2). IR and Raman spectra of KMS6 (M = Mg,Ni) have been recorded and analyzed. From the spectra, the vibrations due to SO4 2- ion, the complex [M(H2O)6]2+ and the water molecules have been identified. Thermogravimetry, differential thermal analysis and XRD at high-temperature investigations show that the dehydration of these salts occurs between 300 and 500 K. This indicates the removal of all water molecules around 426 K. © 2016 Published by Elsevier B.V.


Marzougui H.,University of Carthage | Martin I.R.,University of La Laguna | Attia-Essaies S.,University of Carthage | Attia-Essaies S.,Center National des Recherche en science des Materiaux | And 3 more authors.
Optical Materials | Year: 2015

Eu3+ doped K2Mg(SO4)2.6H2O crystal was prepared by evaporation method at room temperature. A complete structure characterization including X-ray diffraction, Raman and infrared was carried out. The results reveal that this crystal crystallizes in a monoclinic structure and the most active phonons are associated with vibrations of molecular water and sulfate environments. On the other hand, the emission spectrum indicates that Eu3+ ions occupy two different sites. Therefore, a study about the luminescence from each local environment is presented. The emission spectra and luminescence decays of Eu3+ ions indicate than there are not energy transfer processes between both sites. © 2015 Elsevier B.V. All rights reserved.


Messaadi A.,El Manar Campus University | Ouerfelli N.,El Manar Campus University | Das D.,Dinhata College | Hamda H.,Laboratoire dIngenierie Mathematique | Hamzaoui A.H.,Center National des Recherche en science des Materiaux
Journal of Solution Chemistry | Year: 2012

The study of physical properties of binary liquid mixtures is of great importance for understanding and characterizing intermolecular interactions. Similarly, some models attempt to correlate viscosity in liquid mixtures in order to illuminate interacting structures and peculiar behaviors. Grunberg-Nissan parameters for viscosity (η) in isobutyric acid + water mixtures over the entire range of mole fractions under atmospheric pressure and from 302.15 to 313.15 K were calculated from experimental dynamic viscosities presented in previous works. Many experimenters investigate physicochemical properties using various models to develop interpretations and conclusions. The present work comes within the framework of correlating different equations. Relationships between the Grunberg-Nissan and Arrhenius and Jouyban-Acree parameters for viscosity are shown in one critical binary mixture. © 2012 Springer Science+Business Media New York.


Marzougui H.,University of Carthage | Martin I.R.,University of La Laguna | Attia-Essaies S.,University of Carthage | Attia-Essaies S.,Center National des Recherche en science des Materiaux | And 3 more authors.
Optical Materials | Year: 2015

Eu3+ doped K2Mg(SO4)2{dot operator}6H2O crystal was prepared by evaporation method at room temperature. A complete structure characterization including X-ray diffraction, Raman and infrared was carried out. The results reveal that this crystal crystallizes in a monoclinic structure and the most active phonons are associated with vibrations of molecular water and sulfate environments. On the other hand, the emission spectrum indicates that Eu3+ ions occupy two different sites. Therefore, a study about the luminescence from each local environment is presented. The emission spectra and luminescence decays of Eu3+ ions indicate than there are not energy transfer processes between both sites. © 2015.

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