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Chulli B.,Water Researches and Technologies Center | Davraz A.,Suleyman Demirel University of Turkey | Makni J.,University of Sfax | Bedir M.,Water Researches and Technologies Center | Dhia H.B.,University of Sfax
Environmental Earth Sciences | Year: 2012

The Sfax Basin in eastern Tunisia is bounded to the east by the Mediterranean Sea. Thermal waters of the Sfax area have measured temperatures of 23-36°C, and electrical conductivities of 3,200 and 14,980 μS/cm. Most of the thermal waters are characterized as Na-Cl type although there are a few Na-SO 4-Cl waters. They issue from Miocene units which are made up sands and sandstones interbedded with clay. The Quaternary sediments cap the system. The heat source is high geothermal gradient which are determined downhole temperature measurements caused by graben tectonics of the area. The results of mineral equilibrium modeling indicate that the thermal waters of the Sfax Basin are undersaturated with respect to gypsum, anhydrite and fluorite, oversaturated with respect to kaolinite, dolomite, calcite, microcline, quartz, chalcedony, and muscovite. Assessments from various chemical geothermometers, Na-K-Mg ternary and mineral equilibrium diagrams suggest that the reservoir temperature of the Sfax area can reach up to 120°C. According to δ 18O and δ 2H values, all thermal and cold groundwater is of meteoric origin. © 2011 Springer-Verlag.


Eturki S.,Water Researches and Technologies Center | Jedidi N.,Water Researches and Technologies Center | Ben Dhia H.,University of Sfax
Surface Engineering and Applied Electrochemistry | Year: 2012

This article investigates the potential of clay material (bentonite), having the following structure formula Ca 0.014Na 0.404K 0.16(Si 7.65Al 0.35)(Al 2.910Fe 0.762Mg 0.376)O 22, as an ion exchange medium for ammonium removal from effluent and watercourse. Batch experiments were carried out indicating that bentonite is highly selective for the ammonium ion. Experimental data show that 94% of ammonium was removed from aqueous solution in comparison with its initial concentration, with an overall ion exchange capacity of ≈50 meq/100 g medium: on average. Batch tests were performed under a range of conditions to assess the effect of contact time, solution pH, solution concentration and temperature on the performance and capacity of the media for this application. A detailed examination of the data shows that increasing solution concentration and increased contact time provide the best performance at an optimum pH between 6 and 8. Adsorption capacity varied from 34 to 48 meq/100 g with temperature increasing from 20 to 40°C, therefore ammonium removal was controlled essentially by an endothermic process based on chemisorption phenomena. The Langmuir and Freundlich models (isotherms) were applied to the data obtained from the batch studies. It seems that the second model fits well with the experimental data, since it exhibits more satisfactory correlation coefficient value (0.97 and 0.45, respectively). © 2012 Allerton Press, Inc.


Belila A.,Water Researches and Technologies Center | Fazaa I.,Water Researches and Technologies Center | Hassen A.,Water Researches and Technologies Center | Ghrabi A.,Water Researches and Technologies Center
International Journal of Environmental Science and Technology | Year: 2013

The molecular diversity of the purple photosynthetic bacteria was assessed during temporal pigmentation changes in four interconnected wastewater stabilization ponds treating domestic wastewater by denaturant gel gradient electrophoresis method applying pufM gene. Results revealed high phylogenetic diversity of the purple phototrophic anoxygenic bacteria community characterized by the presence of the purple non-sulfur, purple sulfur, and purple aerobic photosynthetic anoxygenic bacteria. This phototrophic bacterial assemblage was dominated by the purple non-sulfur bacteria group (59.3 %) with six different genera followed by the purple sulfur community (27.8 %) with four genera and finally 12.9 % of the pufM gene sequences were assigned throughout the aerobic anoxygenic phototrophic bacterial group. The purple phototrophic bacterial community was characterized by the presence of salt-dependant bacterial species belonging to the genus Marichromatium, Thiorhodococcus, Erythrobacter, and Roseobacter. The wastewater treatment plant performances were unsatisfactory, and the biological and chemical parameters suggested that the purple photosynthetic bloom was correlated with the eutrophic state. © 2013 Islamic Azad University (IAU).


El Amari A.,Water Researches and Technologies Center | Gharbi M.,Water Researches and Technologies Center | Youssef M.B.,Water Researches and Technologies Center | Masrouhi A.,King Abdulaziz University
Arabian Journal of Geosciences | Year: 2016

We used field data collected from the Bir Oum Ali structure (BOAS) and take into consideration recent published geophysical works to evaluate the deformation style and the structural evolution of the Southern Atlassic foreland in Northern Chotts Range in Tunisia. Various structural interpretations have been proposed for the genesis of the Northern Chotts Range. The BOAS was interpreted previously as (1) curved, right-stepping “en echelon” geometry folds as the result of NW-trending lateral strike-slip faulting (2), an anticline structure developed and the result of Ramp-related folding deformed the sedimentary cover (thin-skinned model) over the rigid basement during a single tectonic event (3), response of salt tectonic that began in Early Jurassic and allows the migration to nucleated folding during tertiary compressional events. New field data of the BOAS show a deformation style, in which shortening is differently accommodated in the eastern, southern, and northern areas. Data highlight a tight folding and steeply to overturned strata related to the N100–110° E-trending Bir Oum Ali–Hachichina fault systems (BOAHFS). This later exhibits fault kinematics, with striation showing a multiphase history. The second-order fault systems associated to the main trend of the BOAHFS are usually apparent strike-slip faults. Unfolding of the structure shows an inherited normal faulting. In addition, the normal faulting generates syntectonic conglomerates associated to the first normal faulting movement. The E-trending fold-related fault reactivation of the E-trending Northern Chotts Range might result from the reactivation of inherited Mesozoic faulting. A new structural data interpretation give information of tectonic inversion starting in Late Cretaceous (Campanian–Maastrichtian transition?). The Late Cretaceous to present-day history is dominated by two major events, i.e., Eocene Atlassic contractional event and Middle–Late Miocene to present-day Alpine event. The folding style, the partial reverse–reactivation of the pre-existing E-trending BOAHFS major faults, and the abundant thick tertiary siliciclastic growth strata sequences together with the recent published geophysical data provide a coherent model, in which the thick-skinned tectonic style (development with basement inversion at the depth) is synchronous of thin-skinned tectonic (shallow decollement in the sedimentary cover). © 2016, Saudi Society for Geosciences.


Hachani F.,Water Researches and Technologies Center | Balti H.,University of Carthage | Kadri A.,University of Carthage | Gasmi M.,University of Carthage
Acta Geophysica | Year: 2016

Located between eastern segments of the Atlas and Tell-Rif orogenic belts, the "Dome zone" of northern Tunisia is characterized by the juxtaposition of various structures that mainly controlled the long geodynamic history of this part of the south-Tethyan Margin. To better understand the organization and deep extension of these structures, gravity data from the Teboursouk key area are proposed. These data include the plotting of Bouguer anomaly map and related parameters such as vertical and horizontal gradients, upward continuation and Euler solution. Compared to geological and structural maps available, they allow the identification of new deep structures and greater precision regarding the characteristics and organization of known ones; consequently, an updated structural pattern is proposed. © 2016 Hachani et al. Institute of Geophysics, Polish Academy of Sciences.


Masrouhi A.,Water Researches and Technologies Center | Masrouhi A.,Aix - Marseille University | Bellier O.,Aix - Marseille University | Ben Youssef M.,Water Researches and Technologies Center | Koyi H.,Uppsala University
Journal of African Earth Sciences | Year: 2014

We used structural, stratigraphic and sedimentologic data, together with a comparison of nearby structures and a Bouguer gravity map, to evaluate the evolution of the Bled Dogra salt structure (northern Tunisia) during the Cretaceous. Triassic salt sheets are recognized in the northwestern region of the Tunisian Atlas. These salt sheets are the result of Cretaceous thick and/or thin-skinned extension along the south Tethyan margin. The Bled Dogra salt structure is one of these submarine allochthonous salt sheets, which was emplaced during the Early Cretaceous. The geologic framework, during this period, produces conditions for a predominantly gravity-driven deformation: extension has produced space for the salt to rise; vigorous differential sedimentation created differential loading that resulted in the emplacement and extrusion of a large volume of Triassic salt and formation of large submarine salt sheets. Geologic field data suggest an interlayered Triassic salt sheet within Albian sequences. Salt was extruded at the sea floor during the Early-Middle Albian and was initially buried by Middle-Late Albian strata. The Coniacian corresponds to a second transgressive cover onto the salt sheet after the gliding of the first salt cover (Late Albian-Turonian). In addition, this northwest Tunisian area exposes evidences for salt flow and abundant slump features at the base of a northward facing submarine slope, which was probably dominant from the Early Cretaceous to Santonian. Two gravity deformation processes are recognized: gravity gliding and gravity spreading. Acting concurrently, these two processes appear indistinguishable in this geologic context. Like the present-day salt-involved passive margins - such as the northern Gulf of Mexico, the Atlantic margin of Morocco, the Brazilian Santos basin, the Angola margin, Cadiz in western Iberia, and the Red Sea - the North African Cretaceous passive margin in Tunisia provides evidences that deformation in a passive-margin salt basin is predominantly gravity-driven deformation. © 2014 Elsevier Ltd.


Hadhemi B.,University of Carthage | Fatma H.,Water Researches and Technologies Center | Ali K.,University of Carthage | Mohamed G.,University of Carthage
Journal of African Earth Sciences | Year: 2016

Gravity data was used to investigate sub-surface structure of the Teboursouk and El Krib plains belonging to the dome zone in the Northwest of Tunisia. Analysis of the gravity data included the computation of the Bouguer anomaly, the horizontal and vertical gravity gradients, the upward continuations, Euler deconvolution and analytic signal of high-resolution. The Bouguer anomaly map (d = 2.4 g cm-3) has provided information on the variation of the underground density and shown contrasting anomalous zones. The treatments applied to the Bouguer anomaly map have detected new deep faults and provided details on their dips and depths (exceeding 1500 m per places).Statistical analysis of the gravity data filtering shows that the study area is divided by four major faults with NW-SE, NE-SW, E-W and N-S trends. These faults have contributed to the structuring of the area.The results provide confirmation of some faults already recognized or inferred from the previous structural studies, and specify their depths and dips. While large number of new faults that remained undetected until now, have been highlighted. © 2016 Elsevier Ltd.


Fourti O.,Water Researches and Technologies Center | Jedidi N.,Water Researches and Technologies Center | Hassen A.,Water Researches and Technologies Center
American Journal of Environmental Sciences | Year: 2011

Problem statement: The aim of this study was mainly focused on the evolution of microbial biomasses C and N during the composting of municipal solid wastes. Approach: The carbon and the nitrogen of the microbial biomass (B C and B N) were studied using the fumigation-extraction method. Results: The dynamics of the B C/B N ratio, index of the chemical composition of the whole microbial population suggested a shift in the composition of microbial populations during the process from prevailing bacteria and actinomycetes to prevailing fungi. Conclusion/Recommendations: Microbial characterization of composting is of importance for the optimization of the process and the quality of the end product. © 2010 Science Publications.


Akrout H.,Water Researches and Technologies Center | Bousselmi L.,Water Researches and Technologies Center
Arabian Journal of Geosciences | Year: 2013

The electrochemical oxidation of synthetic wastewater which contains biazo dye [amido black (AB)] on boron-doped diamond anode, "BDD anode," was experimentally investigated to determine the influence of several operative parameters on the performance of the process. The study focalized on the effect of studied parameters on discoloration process and the degradation of the aromatic part of the dye molecule. Two distinct pathways with two different kinetics were observed. The decrease of pH improves the discoloration rate and the degradation of aromatic by-products after 90 min of electrolysis. The increase of current density has a considerable effect on discoloration and a little less effect on the aromatic derivative degradation. Hypochlorite electrogenerated from chloride addition exceptionally accelerates the discoloration, but it does not degrade aromatic derivatives as efficiently. It was observed that nitrates addition generates under electrolysis other derivates of AB as different colors than the dye one. The current efficiency depends very little on the initial pH; however, higher energy consumptions are obtained. © 2012 Saudi Society for Geosciences.


PubMed | National Agronomic Institute of Tunisia, Water Researches and Technologies Center and University of Naples Federico II
Type: | Journal: Chemosphere | Year: 2016

Pentachlorophenol (PCP) is a toxic compound which is widely used as a wood preservative product and general biocide. It is persistent in the environment and has been classified as a persistent organic pollutant to be reclaimed in many countries. Fungal bioremediation is an emerging approach to rehabilitating areas fouled by recalcitrant xenobiotics. In the present study, we isolated two fungal strains from an artificially PCP-contaminated soil during a long-term bioremediation study and evaluated their potential as bioremediation agents in depletion and detoxification of PCP in soil microcosms. The two fungal strains were identified as: Byssochlamys nivea (Westling, 1909) and Scopulariopsis brumptii (Salvanet-Duval, 1935). PCP removal and toxicity were examined during 28 days of incubation. Bioaugmented microcosms revealed a 60% and 62% PCP removal by B.nivea and S.brumptii, respectively. Co-inoculation of B.nivea and S.brumptii showed a synergetic effect on PCP removal resulting in 95% and 80% PCP decrease when initial concentrations were 12.5 and 25mgkg

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