30 research outputs found

    Cohomologie de Chevalley des graphes ascendants

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    The space Tpoly(Rd)T_{poly}(\mathbb R^d) of all tensor fields on Rd\mathbb R^d, equipped with the Schouten bracket is a Lie algebra. The subspace of ascending tensors is a Lie subalgebra of Tpoly(Rd)T_{poly}(\mathbb R^d). In this paper, we compute the cohomology of the adjoint representations of this algebra (in itself and Tpoly(Rd)T_{poly}(\mathbb R^d)), when we restrict ourselves to cochains defined by aerial Kontsevitch's graphs like in our previous work (Pacific J of Math, vol 229, no 2, (2007) 257-292). As in the vectorial graphs case, the cohomology is freely generated by all the products of odd wheels

    Conception d’un nouveau protocole pour le réseau de capteurs sans fils

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    dans ce présent papier, nous proposons un nouveau protocole pour le réseau de capteur sans fils. Le défi principal de ce protocole reste d’augmenter la durée de vie de réseau de capteur sans fils. Ce protocole de réseau est dédié pour le réseau de capteur sans fils de grande taille. Pour cela nous exploitons deux aspects, un aspect basé sur la décomposition de réseau de capteur en cluster ou zone et la deuxième repose sur le protocole MAC MIMO coopérative. nous développons un modèle analytique qui vise à calculer la probabilité d’erreur puis nous calculons la consommation d’énergie et le délai de transmission en fonction de la probabilité d’erreur de transmission et le taux d’erreur binaire pour la transmission point à point et MAC MIMO coopérative

    New ion exchange membrane derived from sulfochlorated polyether sulfone for electrodialysis desalination of brackish water

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    The purpose of this work is to study the desalination of brackish water using a new ion exchange membrane, made from sulfochlorated polyethersulfone (Cl-PES), and crosslinked using aminated polyethersulfone (NH2-PES) as a crosslinking reagent. This membrane, named ClNH2 membrane, has been obtained by reaction between Cl-PES with 1.3 SO2Cl groups per monomer unit and 0.2 equivalent amount of NH2-PES. ClNH2 membrane has been characterized in terms of contact angle, transport number, intrinsic conductivity, and water uptake (as a function of temperature). Electrodialysis performances of the newly synthetized membranes have been measured using an electrodialysis cell at a laboratory scale and compared to commercial membranes. All the experiments have been performed using synthetic brackish water solutions prepared from sodium chloride salts with different concentrations (varying from 0.5 to 5.0 g/L). The concentration of different water samples obtained has been found to be below the amount recommended by the World Health Organization (WHO) for drinking water.ERAS Labo; World Health Organizatio

    Outcomes of treatment of severe COVID-19 pneumonia with tocilizumab: a report of two cases from Tunisia

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    The SARS CoV-2 pandemic is a global health threat with high morbidity and mortality (1 to 4%) rates. COVID-19 is correlated with important immune disorders, including a “cytokine storm”. A new therapeutic approach using the immunomodulatory drug, Anti-IL6 (tocilizimub), has been proposed to regulate it. We report here the first Tunisian experience using tocilizimub in two severe cases of COVID-19 pneumonia. The diagnosis was confirmed by chest scan tomography. Biological parameters showed a high level of Interleukin-6 (IL-6) that increased significantly during hospitalization. The patients developed hypoxia, so they received intravenously 8 mg/kg body weight tocilizumab. There was a resultant decrease in the level of IL6, with clinically good evolution. Blocking the cytokine IL-6 axis is a promising therapy for patients developing COVID-19 pathology

    Valorization of lignocellulosic biomass into sustainable materials for adsorption and photocatalytic applications in water and air remediation

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    An exponential rise in global pollution and industrialization has led to significant economic and environmental problems due to the insufficient application of green technology for the chemical industry and energy production. Nowadays, the scientific and environmental/industrial communities push to apply new sustainable ways and/or materials for energy/environmental applications through the so-called circular (bio)economy. One of today’s hottest topics is primarily valorizing available lignocellulosic biomass wastes into valuable materials for energy or environmentally related applications. This review aims to discuss, from both the chemistry and mechanistic points of view, the recent finding reported on the valorization of biomass wastes into valuable carbon materials. The sorption mechanisms using carbon materials prepared from biomass wastes by emphasizing the relationship between the synthesis route or/and surface modification and the retention performance were discussed towards the removal of organic and heavy metal pollutants from water or air (NOx, CO2, VOCs, SO2, and Hg0). Photocatalytic nanoparticle–coated biomass-based carbon materials have proved to be successful composites for water remediation. The review discusses and simplifies the most raised interfacial, photonic, and physical mechanisms that might take place on the surface of these composites under light irradiation. Finally, the review examines the economic benefits and circular bioeconomy and the challenges of transferring this technology to more comprehensive applicationsOpen access funding provided by Universitat Rovira i Virgili. Authors are thankful for the support from Grant PID2021-123665OBI00 and TED2021-129343B-I00 funded by MCIN/AEI/ 10.13039/501100011033 and, as appropriate, by “ERDF A way of making Europe”, by the “European Union” or by the “European Union NextGenerationEU/PRTR”. Dr Ridha Djellabi acknowledges Maria Zambrano Grants-2021URV-MZ-1
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