Women's political participation in Tunisia. Arab Citizenship Review No. 14, 21 January 2016

The collapse of the authoritarian regime in Tunisia in 2011 has given women new opportunities to participate in political life and in civil society activities, standing for elections (2011 and 2014) or becoming members of political parties and associations. Nevertheless, despite these advances and the already positive point of de- parture thanks to the legacy of Bourguiba, the “liberator of the country and the women”, participation of women remains unsatisfactory. While Tunisian women have enjoyed extended individual rights, especially compared to Arab women in general, since the country became independent in 1956, their political participation has remained controlled by the state.T he challenge of increasing the political participation of women, even in a democratic phase of the country’s political life, remains.The new electoral laws from 2011 and 2014 endorse parity and women rights, now guaranteed by the Constitution. However, the implementation of these rights is still at stake

Tunisia. Supervising Tunisian Elections by civil society: How to improve it? Arab Citizenship Review No. 7. January 2015

Introduction. On October 26, 2014, Tunisia held its second democratic legislative elections. Participation among more than 5 million registered voters was at about 60%, a relatively good turnout for the country, compared to the 52% voters in 2011. Preliminary results for the 33 constituencies (27 within the country and 6 for expatriates) reveal that secular frontrunner Nidaa Tounes (Call of Tunisia) won around 37% percent of votes while moderate Islamist party Ennahdha, winner of the 2011 elections and leader of Tunisia’s post-revolution government, received 27% of votes. Other parties with notable percentages are the Free Patriotic Union (French: UPL) with 4.4% and the leftist party, Popular Front, with 3.7%. Legislative were immediately followed by two round presidential elections the first one held on November 23, the second one after one month. Conversely to what was expected, people were more attracted by presidential elections even though president has notably less prerogatives than the parliament: representing the state, he is mainly responsible for determining the general state policies in the domains of defense, foreign relations and national security (article 76.) This paradox is ascribed to national imaginary more confident in a “Zaïm” (leader) rather than a collective institution such as a parliament. The turnout was at about 64% within the national 27 constituencies. Out of 70 candidates (including 5 female), 27 (with only one female) met the legal requirements to run for the presidency. The result confirms the legislative trend and Beji Caid Essebsi, leader of Nidaa, was proclaimed the third President of Tunisia. He gained 39.46% of the votes at the first round elections. Essebsi was followed by Moncef Marzouki who received an unexpected score (33.43%) at the first round, thanks to the support of Ennahdha audience and to an active and insistent campaign focused on the idea that revolution is threatened by old regime guard “come-back.” Rewarded for his long militant live, the extreme leftist Hamma Hammami in a new look gained 7,8% of the votes while the new comer Slim Riahi received 5,5% despite rumors circulating on his personal reputation. Notably, Kalthoum Kennou gained 0,55% (18.287 votes) but listed eleventh out of 27

Optimal control of membrane filtration systems

International audienceThis paper studies an optimal control problem related to membrane filtration processes. A generic mathematical model of membrane fouling is used to capture the dynamic behavior of the filtration process which consists in the attachment of matter onto the membrane during the filtration period and the detachment of matter during the cleaning period. We consider the maximization of the net water production of a membrane filtration system (i.e. the filtrate) over a finite time horizon, where the control variable is the sequence of filtration/backwashing cycles over the operation time of process. Based on the Pontryagin Maximum Principle, we characterize the optimal control strategy and show that it exhibits a singular arc. Moreover we prove the existence of an additional switching curve before reaching the terminal state, and also the possibility of having a dispersal curve as a locus where two different strategies are both optimal

Fractionation of homologous CD6 to CD60 cyclodextrin mixture by ultrafiltration and nanofiltration

This paper investigates the membrane purification and fractionation of a mixture containing the homologous series of cyclodextrins CD6 to CD60 obtained by enzymatic conversion of starch. Three commercial polyamide thin film composite NF and UF membranes (HL, GH and GK from GE-Osmonics) were used for this purpose. In a first step, a binary mixture composed of glucose and heptacyclomaltose (β-cyclodextrin, CD7) was filtered to examine the separation performance of the studied membranes. A mathematical model based on mass balance was proposed for the simulation of the discontinuous diafiltration process assuming that the membrane separation performance is based on a sieving mechanism. A three stage diafiltration cascade (in retentate configuration) was then selected to fractionate the CD6–CD60 crude mixture. The experimental composition of the obtained permeate and retentate solutions in the targeted fractions (glucose, CD6–CD8, CD9–CD21, CD22–CD60) fit well with the predicted data indicating that membrane process enables purification and fractionation of the homologous series of large ring CDs. Some discrepancies were however observed implying that other mechanisms such as coupled transport also took place. The most striking effect was the presence of glucose in the GK retentate possibly as a result of the formation of inclusion complexes with the large ring CDs

Soluble microbial products and suspended solids influence in membrane fouling dynamics and interest of punctual relaxation and/or backwashing

International audienceTo favor the control of membrane fouling on line by relaxation and backwash sequencing, two major fouling origins are considered: the former is due to retention of large particles on the membrane surface forming a growing deposit that can be controlled by tangential shear stresses, the second is due to the retention of the largest soluble polymers forming a thin layer on the membrane surface including pore blocking and inducing a progressive reduction of the deposit porosity, the influence of this second fouling origin can only be reduced by backwashing. A simple model was developed to represent (i) the accumulation of two types of compounds and its consequences and the evolution with time of the hydraulic resistance of the system and (ii) the role of relaxation and backwashing to reduce the fouling impact. Some simulations were presented according to the values of the three model parameters. Simulations were also compared to experimental data obtained on biological suspensions

Étude comparative de deux méthodes de caractérisation de membranes d’ultrafiltration et de nanofiltration : la porométrie bi-liquide et le transport de solutés neutres

International audienc

Selective separation of α- and β-cyclodextrins by complexation/ultrafiltration using supra molecular host-guest interaction

International audienceThis work is aimed at developing a new process to separate alpha-cyclodextrin (CD) from binary alpha-CD/beta-CD mixtures. To achieve this objective, a membrane process was designed with water as solvent and using the selective accommodation of a guest Igepal Co-890 (IG) within the beta-CD cavity. In the first part, host-guest inclusion study suggested the formation of IG(2)/beta-CD complex in presence of IG excess. Moreover, increasing IG/CD molar ratio to 1.5 leads to the complete complexation of beta-CD while alpha-CD remains free. The second part was devoted to the separation of alpha- and beta-CD using UF membranes (GH and GK from GE-Osmonics). The influence of parameters including membrane molecular weight cut-off (MWCO), transmembrane pressure (Delta P), IG/beta-CD and alpha-CD/beta-CD molar ratios, was investigated. MWCO, Delta P, IG/beta-CD and alpha-CD/beta-CD molar ratios respectively of 1000 Da, 2 bar, 1.5 and 11:89 are the optimized values to reach an alpha-CD separation factor as high as 38. The experimental data fits very well with predicted values calculated using the parameters found in the complexation study and rejection of single solutions indicating that selectivity predominantly originates from steric exclusion of species by membrane GH

Influence des paramètres procédés sur les performances des membranes polymères de nanofiltration

Parmi les différents procédés membranaires, la nanofiltration (NF) apparaît comme la technique séparative possédant le plus fort potentiel de développement dans les années à venir. Cette technique relativement récente a d'ores et déjà su s'imposer dans de nombreux secteurs du monde industriel et elle continue de susciter d'importants efforts en matière de recherche et de développement. Les performances de séparation d'une membrane de NF sont fortement dépendantes des conditions opératoires. L'objectif de ce travail de thèse est d'étudier et de comprendre l'influence de la température et du pH sur le flux de perméation de différentes membranes polymères commerciales et sur leur aptitude à retenir des solutés neutres ou des électrolytes. Les résultats montrent que les paramètres étudiés ont une grande influence sur les performances de la NF (flux et de rétention). Des études de caractérisation ont par ailleurs été réalisées, dans le but de déterminer la relation entre les propriétés physico-chimiques de la membrane et sa performance. A l'issu de cette étude, nous avons montré que les paramètres les plus sur la NF sont : la température de transition vitreuse et la charge de la couche active de la membraneThe applications of nanofiltration (NF) in the water treatment and industrials effluents are in a continuous development. The influence of the process parameters on the performances of the NF membranes is a special concern. The present work shows the influence of the temperature and the pH of a feed solution containing neutral and charged solutes on the permeability and the retention capacity of the several polymeric commercial NF membranes. The results show that the studied parameters have a considerable influence on the performance of NF. Characterization studies were also done to determine the relationship between physicochemical properties and the membrane performances. The parameters that affect the most NF operation: the glass transition temperature of the thin active layer and membrane charge densityMONTPELLIER-BU Sciences (341722106) / SudocSudocFranceTunisiaFRT