Tunis University

About: Tunis University is a education organization based out in Tunis, Tunisia. It is known for research contribution in the topics: Population & Thin film. The organization has 11745 authors who have published 15400 publications receiving 154900 citations. The organization is also known as: University of Tunis & UT.

Geospatial and AHP-multicriteria analyses to locate and rank suitable sites for groundwater recharge with reclaimed water

Abstract: The reuse of reclaimed water in arid and semi-arid regions to recharge aquifers contribute to reduce pressure on conventional water. An appropriate site selection preceding the construction of the basins is required to insure the success of the process. The aim of this research is to develop a methodology to locate and rank suitable sites for groundwater recharge with reclaimed water based on a combination of geospatial and multicriteria analyses. Seven constraints were chosen to identify the suitable areas for aquifer recharge with reclaimed water. A vector spatial layer of each was obtained and the feasible areas were delineated by an intersection operator. To rank these areas three main criteria were identified having technical, economical and environmental aspects, from which twelve sub-criteria were derived. All of them were organized in a decision hierarchy structure and weighted using Saaty pair-wise comparison matrixes. A raster spatial layer of each sub-criterion was obtained and their values were standardized using fuzzy logic functions. A weighted linear combination was carried out to get the decisional index layer from which the suitable sites were ranked. Finally a sensitivity analysis was carried out in order to quantify the influence of the criteria weights on the resulting decision spatial layer. The study area selected to develop the methodology is the Nabeul–Hammamet shallow aquifer. The feasible area for aquifer recharge with reclaimed water is about 5160 ha. This area exceeds by far the needed 39 ha to absorb the total effluents of the SE3 and SE4 wastewater treatment plants present in the case study. The best 39 ha are located in the north west of the city of Nabeul for SE3 and in the northern west and the south west of the city of Nabeul for SE4. For best management and cost reduction it is preferable to gather these sites in a unique area located in the north west of the city of Nabeul in an agricultural region and far from the urban zones.

Highly Selective Polypyrrole MIP-Based Gravimetric and Electrochemical Sensors for Picomolar Detection of Glyphosate.

Abstract: There is a global debate and concern about the use of glyphosate (Gly) as an herbicide. New toxicological studies will determine its use in the future under new strict conditions or its replacement by alternative synthetic or natural herbicides. In this context, we designed biomimetic polymer sensing layers for the selective molecular recognition of Gly. Towards this end, complementary surface acoustic wave (SAW) and electrochemical sensors were functionalized with polypyrrole (PPy)-imprinted polymer for the selective detection of Gly. Their corresponding limits of detection were on the order of 1 pM, which are among the lowest values ever reported in literature. The relevant dissociation constants between PPy and Gly were estimated at [Kd1 = (0.7 ± 0.3) pM and Kd2 = (1.6 ± 1.4) µM] and [Kd1 = (2.4 ± 0.9) pM and Kd2 = (0.3 ± 0.1) µM] for electrochemical and gravimetric measurements, respectively. Quantum chemical calculations permitted to estimate the interaction energy between Gly and PPy film: ΔE = −145 kJ/mol. Selectivity and competitivity tests were investigated with the most common pesticides. This work conclusively shows that gravimetric and electrochemical results indicate that both MIP-based sensors are perfectly able to detect and distinguish glyphosate without any ambiguity.