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Zaier H.,Center de Biotechnologie de la Technopole de Borj-Cedria | Ghnaya T.,Center de Biotechnologie de la Technopole de Borj-Cedria | Ghabriche R.,Center de Biotechnologie de la Technopole de Borj-Cedria | Chmingui W.,CNRS Institute of Chemistry | And 4 more authors.
Environmental Science and Pollution Research | Year: 2014

The low bioavailability of Pb and low number of Pb-tolerant plant species represent an important limitation for Pb phytoextraction. It was recently suggested that halophyte plant species may be a promising material for this purpose, especially in polluted salt areas while Pb mobility may be improved by synthetic chelating agents. This study aims to evaluate Pb extraction by the halophyte Sesuvium portulacastrum in relation to the impact of EDTA application. Seedling were cultivated during 60 days on Pb artificially contaminated soil (200, 400, and 800 ppm Pb) in the presence or in the absence of EDTA (3 g kg-1 soil). Results showed that upon to 400 ppm, Pb had no impact on plant growth. However, exogenous Pb induce a decrease in shoot K+ while it increased shoot Mg2+ and had no impact on shoot Ca2+ concentrations. Lead concentration in the shoots increased with increasing external Pb doses reaching 1,390 ppm in the presence of 800 ppm lead in soil. EDTA addition had no effect on plant growth but strongly increased Pb accumulation in the shoot which increased from 1,390 ppm in the absence of EDTA to 3,772 ppm in EDTA-amended plants exposed to 800 ppm exogenous Pb. Both Pb absorption and translocation from roots to shoots were significantly enhanced by EDTA application, leading to an increase in the total amounts of extracted Pb per plant. These data suggest that S. portulacastrum is very promising species for decontamination of Pb2+-contaminated soil and that its phytoextraction potential was significantly enhanced by addition of EDTA to the polluted soil. © 2014 Springer-Verlag Berlin Heidelberg. Source

Azri C.,University of Sfax | Mabrouk C.,University of Sfax | Abida H.,University of Sfax | Medhioub K.,Institute Preparatoire Aux Etudes Dingenieurs Of Sfax
Atmosfera | Year: 2010

This study examines the influence of source and meteorological factors on the physico-chemical characteristics of atmospheric aerosols collected at two sampling sites, urban and suburban, in the city of Sfax (Tunisia) during the year of 2004. Atmospheric aerosols were further analyzed for their chemical composition and spatio-temporal evolution was investigated. Based on particle content distribution, the species studied were classified into distinct groups with different content and temporal distribution. A principal component analysis (PCA) revealed a clear relationship between the behavior of the constituents of each group and their corresponding source and meteorological factors. The findings provide sheer evidence for a marked intra-site enrichment that depended on the soil state, the frequency of exposition to the industrial plumes and the transport phenomena. Source apportionment revealed three major groupings. Group I consisted of a natural source including maritime (Cl- et Na+) and crustal (Ca++, Mg++, Fe(2;3)+ and K+) elements. Group II is associated with a "primary" anthropic source attributed to the local effect of industrial plume fallouts which threatens the urban site. This mainly concerns the PO4 3- compound. The third group is explained by a "secondary" anthropic source that included NH4 +, NO3 - and SO4 = compounds resulting from the effect of gas/particles conversion processes. Source

Houda B.,University of Sfax | Dorra G.,University of Sfax | Chafai A.,University of Sfax | Emna A.,University of Sfax | Khaled M.,Institute Preparatoire Aux Etudes Dingenieurs Of Sfax
International Journal of Environmental Research | Year: 2011

Concentrations of Zn, Cu, Cr, Cd, Pb and Fe in surface marine sediments of the southern coast of Sfax were studied in order to understand current metal contamination at the outlet of a mixed industrial and domestic wastewater effluent discharged into the seawater since 1953. We found that heavy metal concentrations (mg/kg dry weight) in surface marine sediments varied from 42 to 391 for Zn, 15 to 44 for Cu, 44 to 137 for Cr, 6 to 56 for Cd, 19 to 59 for Pb and 52344 to 54543 for Fe. The computed metal enrichment factors (EF) in the sediments showed that EF of Zn ranged from 0.49 to 9.13, EF of Cu from 0.35 to 3.04, EF of Cr from 0.3 to 3.05, EF of Cd from 0.63 to 9.37 and EF of Pb from 0.43 to 3. All heavy metals were characterized by maxima EF values greater than 1.5, indicating a considerable metallic pollution of the study area. The PCA analysis revealed two distinct groups: (i) the first group (G 1) is representative of Fe selected as natural tracer and (ii) the second group (G 2) is articulated around Zn, Cu, Cr, Cd and Pb. These metals which did not show any correlations with Fe of the first group imply a significantly impact of the selected wastewater effluent. The calculation of the geoaccumulation index (I geo) showed that all analyzed metals (except for Fe) can be considered as moderate to extreme pollutants. The microbial analysis of seawater samples and also of both water and sediment samples collected from the Sfax solar saltern (placed at the vicinity of the outlet of the selected effluent) showed that no indicator germs of contamination (total coliforms, faecal coliforms and faecal streptococci) were detected. Source

Shel F.,Institute Preparatoire Aux Etudes Dingenieurs Of Sfax
Mathematical Methods in the Applied Sciences | Year: 2013

In this paper, we study the stability of a network of some elastic and thermoelastic edges. We establish the exponential decay rate of the whole system. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd. Source

Jerbi A.,University of Sfax | Chtourou H.,University of Sfax | Chtourou H.,Institute Preparatoire Aux Etudes Dingenieurs Of Sfax | Maalej A.Y.,University of Sfax
Journal of Manufacturing Technology Management | Year: 2010

Purpose - A number of simulation studies were conducted by several researchers in order to compare performances of cellular and functional layouts. The methodologies used by these studies either present several objectivity lacks or are highly time-consuming. The purpose of this paper is to propose a novel and objective methodology, based on the coupling of simulation and the Taguchi method. Design/methodology/approach - Simulation models for both layouts are first developed. Simulations are then conducted following a standard Taguchi orthogonal array. Subsequently, the obtained results are analyzed using the analysis of variance technique. Finally, a mathematical model is built, and validated by the confirmation test. Findings - The proposed comparison method permitted to obtain a valid mathematical model used to predict the superiority rank of the two layouts within the scope of the paper. Originality/value - This paper presents a novel objective methodology for comparing functional and cellular layouts. © Emerald Group Publishing Limited. Source

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