Institute Preparatoire Aux Etudes Dingenieurs Of Sfax

Sfax, Tunisia

Institute Preparatoire Aux Etudes Dingenieurs Of Sfax

Sfax, Tunisia
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Ben Jeddou K.,University of Sfax | Bouaziz F.,University of Sfax | Zouari-Ellouzi S.,University of Sfax | Chaari F.,University of Sfax | And 4 more authors.
Food Chemistry | Year: 2017

Demand for health oriented products such as low calories and high fiber product is increasing. The aim of the present work was to determine the effect of the addition of potato peel powders as protein and dietary fiber source on the quality of the dough and the cake. Powders obtained from the two types of peel flour showed interesting water binding capacity and fat absorption capacity. Potato peel flours were incorporated in wheat flours at different concentration. The results showed that peel powders additionally considerably improved the Alveograph profile of dough and the texture of the prepared cakes. In addition color measurements showed a significant difference between the control dough and the dough containing potato peels. The replacement of wheat flour with the potato powders reduced the cake hardness significantly and the L* and b* dough color values. The increased consumption of cake enriched with potato peel fiber is proposed for health reasons. The study demonstrated that protein/fiber-enriched cake with good sensory quality could be produced by the substitution of wheat flour by 5% of potato peel powder. In addition and technological point of view, the incorporation of potato peel powder at 5% increase the dough strength and elasticity-to-extensibility ratio (P/L). © 2016


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.


Ben Difallah B.,University of Sfax | Ben Difallah B.,Institute Preparatoire Aux Etudes Dingenieurs Of Sfax | Ben Difallah B.,ENSMM - National Engineering Institute in Mechanics and Microtechnologies | Kharrat M.,University of Sfax | And 4 more authors.
Materials and Design | Year: 2012

Thermoplastic-based polymer composites containing solid lubricant filler have been developed using a hot compression molding technique. The thermoplastic polymer is Acrylonitrile Butadiene Styrene (ABS) which is of great importance in applications such as bearing and slider material. The solid lubricant employed is graphite powder. Four mass ratios of the graphite particles in the ABS matrix were considered in the range of 0-7.5%. The mechanical properties of ABS composites were investigated using tensile test. The results show that the mechanical properties decrease significantly with the increase of graphite particles amount. Friction experiments were also conducted using a reciprocating tribometer recently developed in our laboratory. For each of the considered mass ratio, evolutions of the friction coefficient, the weight losses and the wear scar micrograph with respect to the number of sliding cycles were analyzed. Severe adhesive wear mechanism is activated for the ABS without graphite particles. Addition of graphite in ABS matrix exhibits lower friction coefficient and weight losses, whose values decrease as the weight fraction of graphite increases in the polymer matrix. Based on scanning electron microscopy (SEM) observations, the worn surface of the filled ABS composites reveals the development of a specific third body which reduces friction and wear. The best friction coefficient and weight loss were obtained with 7.5% in weight (7.5. wt%) of graphite. © 2011 Elsevier Ltd.


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.


Ben Difallah B.,University of Sfax | Ben Difallah B.,Gafsa University | Ben Difallah B.,ENSMM - National Engineering Institute in Mechanics and Microtechnologies | Kharrat M.,University of Sfax | And 4 more authors.
Tribology Transactions | Year: 2014

The present study undertakes the assessment of the effect of the incorporation of molybdenum disulfide (MoS2) flakes on the tribological behavior of polycarbonate (PC) matrix. Five weight ratios of the MoS2 particles in the PC matrix were considered in the range of 0-10 wt%. The composites were developed by direct injection molding. The determination of various tribological parameters after wear testing (friction coefficient, wear volume loss, and profilometric traces) and microscopical observations by scanning electron microscopy (SEM) were combined in an attempt to understand the effect of the solid lubricant in the composites' tribological performance. It was found that the tribological properties were improved by the addition of MoS2 particles. Maximum reductions in the friction coefficient and wear were obtained with an MoS2 mass content of about 7 to 10 wt%. It seems that MoS2 decreases the polymer surface melting by dissipating the generated heat. Under sliding conditions, the incorporation of MoS2 particles enhances the abrasive component in the wear mechanism, which is manifested by the formation of scratches in the two bodies in contact. © 2014 Copyright © Society of Tribologists and Lubrication Engineers.


PubMed | University of Sfax and Institute Preparatoire Aux Etudes Dingenieurs Of Sfax
Type: | Journal: Food chemistry | Year: 2016

Demand for health oriented products such as low calories and high fiber product is increasing. The aim of the present work was to determine the effect of the addition of potato peel powders as protein and dietary fiber source on the quality of the dough and the cake. Powders obtained from the two types of peel flour showed interesting water binding capacity and fat absorption capacity. Potato peel flours were incorporated in wheat flours at different concentration. The results showed that peel powders additionally considerably improved the Alveograph profile of dough and the texture of the prepared cakes. In addition color measurements showed a significant difference between the control dough and the dough containing potato peels. The replacement of wheat flour with the potato powders reduced the cake hardness significantly and the L(*) and b(*) dough color values. The increased consumption of cake enriched with potato peel fiber is proposed for health reasons. The study demonstrated that protein/fiber-enriched cake with good sensory quality could be produced by the substitution of wheat flour by 5% of potato peel powder. In addition and technological point of view, the incorporation of potato peel powder at 5% increase the dough strength and elasticity-to-extensibility ratio (P/L).


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.


Benabdallah A.,Institute Superieur Dinformatique Et Du Multimedia Of Sfax | Kallel J.,Institute Preparatoire Aux Etudes Dingenieurs Of Sfax
Nonlinear Dynamics | Year: 2011

In this paper we propose sufficient conditions for the robust stability of time-invariant uncertain piecewise-linear systems using homogeneous polynomial Lyapunov functions. The proposed conditions are expressed in terms of linear matrix inequalities, which can be numerically determined. We solve the stabilization of piecewise uncertain linear control systems by using state piecewise-linear feedback. We propose an illustrative example to show the efficiency of the proposed approach. © 2010 Springer Science+Business Media B.V.


Khemakhem M.A.,National Engineering School of Tunis | Chtourou H.,Institute Preparatoire Aux Etudes Dingenieurs Of Sfax
International Journal of Industrial and Systems Engineering | Year: 2013

The single-mode resource-constrained project scheduling problem is considered. Traditionally, this problem is solved with the objective of makespan minimisation. But in reality, projects are often subject to diverse sources of uncertainty that could have a negative impact on this objective. That is why, some recent research efforts have focused on the generation of robust project baseline schedules that are protected against possible disruptions that may occur during schedule execution. To provide an accurate estimate of the schedule robustness, they introduced surrogate measures. This paper reviews the main robustness measures (RMs) proposed in the literature. It also presents several new RMs. Using a five-stage approach, the efficiency of all RMs is assessed, in a specific context, by computing the correlation between RMs and a predefined performance measure. The relevance and the efficiency of some new RMs are illustrated. Also, the superiority of the newly proposed RMs over the old ones is statistically proven for a particular perturbation scheme. Hence, these measures could help project managers in discriminating solutions having the same makespan to choose the most robust schedule. Copyright © 2013 Inderscience Enterprises Ltd.


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.

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