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Taha Chabbah Houyem Abderrazak Patrice Saint Martin Herv Casabianca Hans R. Kricheldorf Saber Chatti 《先进技术聚合物》2020,31(10):2339-2350
In this study, biomass‐derived Glux was used as a monomer in the polymerization of a novel semi‐aromatic polyethersulfone and polyester. The characterization of the synthesized polymers was carried out by means of MALDI‐TOF and NMR spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. These two polymers were tested as sorbent phases of two families of pollutants (benzene derivatives and pesticides) in water. The analysis of the target hydrophilic pollutants was successfully achieved using high performance liquid chromatography meanwhile gas chromatography was applied for the detection of the hydrophobic pollutants. The adsorption data demonstrate that the novel polyethersulfone based on Glux can effectively remove the studied organic pollutants (polar and non polar, 90% to 100%) at environmental concentration (tested concentration: 1 mg L?1) simultaneously when present in mixtures. 相似文献
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Brahim Benyahia Mohamed Abderrazak Latifi Christian Fonteix Fernand Pla 《Macromolecular Symposia》2011,302(1):142-150
Summary: This paper deals with the design and control of the morphology of core-shell nanoparticles elaborated by fed-batch emulsion copolymerization of styrene and butyl-acrylate in the presence of a chain transfer agent (n-dodecyl mercaptan). A mathematical model was elaborated and validated. It consists of a system of differential algebraic equations involving 49 unknown kinetic and thermodynamic parameters, many of them being impossible to be accurately estimated, due to the lack of experimental data. A method based on the sensitivity analysis allowed us to determine a subset of the 21 most influential parameters. The 28 non estimable parameters were taken from the literature. The validated model was then used in a dynamic multiobjective optimization to optimize the best profile of the pre-emulsion feed rate to control (i) the composition and average molar masses of the copolymer, (ii) the instantaneous glass transition temperature, corresponding to a core-shell morphology suited for special end-use properties. 相似文献
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Mariem Bourourou Dr. Kamal Elouarzaki Noémie Lalaoui Dr. Charles Agnès Dr. Alan Le Goff Dr. Michael Holzinger Prof. Dr. Abderrazak Maaref Dr. Serge Cosnier 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(28):9371-9375
An efficient way of immobilizing and wiring a large amount of laccase on non‐covalently‐functionalized multi‐walled carbon nanotube (MWCNT) electrodes is reported. 1‐(2‐anthraquinonylaminomethyl)pyrene and 1‐[bis(2‐anthraquinonyl)aminomethyl]pyrene were synthesized and studied for their capability to non‐covalently functionalize MWCNT electrodes and immobilize and orientate laccase on the nanostructured electrodes. This led to high‐performance biocathodes for oxygen reduction by direct electron transfer with maximum current densities of (1±0.2) mA cm?2. The performance of the resulting bioelectrodes could be doubled simply by using the bis‐anthraquinone compound. The bioelectrodes show excellent stability over weeks and can thus be envisioned in enzymatic biofuel cells. 相似文献
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Cobalt doped zinc oxide (ZnO:Co) thin films were deposited on glass substrates by ultrasonic spray technique decomposition of Zinc acetate dihydrate and cobalt acetate tetrahydrate in an ethanol solution with film thickness. All films are polycrystalline with a hexagonal wurtzite-type structure with a preferential orientation according to the direction (0 0 2), with the maximum crystallite size was found of 59.42 nm at 569 nm. The average transmittance of all films is about 65–95% measured by UV–vis analyzer. The band gap energy increased from 3.08 to 3.32 eV with increasing the film thickness from 192 to 569 nm. The increase of the electrical conductivity with increases in the film thickness to maximum value of 9.27 (Ω cm)−1 can be explained by the increase in carrier concentration and displacement of the electrons of the films. The correlation between the band gap and crystal structure suggests that the band gap energy of Co doped ZnO is influenced by the crystallite size and the mean strain. 相似文献
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Zineb Essalhi Bouchaib Hartiti Abderrazak Lfakir Bernabé Mari Philippe Thevenin 《Optical and Quantum Electronics》2017,49(9):301
In this research, Cu-doped TiO2 thin films have been successfully deposited onto a glass substrate by Sol–gel technique using dip coating method. The films were annealed at different annealing temperatures (400–500 °C) for 1 h. The structural, optical and electrical properties of the films were investigated and compared using X-ray Diffraction, UV–visible spectrophotometer and 4-point probe method. Optical analysis by mean transmittance T(λ) and absorption A(λ) measurements in the wavelength range between 300 to 800 nm allow us to determine the indirect band gap energy. DRX analysis of our thin films of TiO2:Cu shows that the intensities of the line characteristic of anatase phase increasing in function of the temperature. 相似文献
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Mohamed Fathi Karoui Hassane Alla Abderrazak Chatti 《Nonlinear Analysis: Hybrid Systems》2010,4(4):766-774
In this paper we develop a method of monitoring dynamic processes based on rectangular hybrid automats. This method takes into account the behavior of the system and the evolution of its parameters. A failure during the execution of the process can lead to a dysfunctional state in the system.The monitoring system, we propose, makes it possible to detect this state of dysfunction as soon as possible thanks to the reachability analysis. 相似文献
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Dans un article précédent, nous avons démontré que si D est un opérateur différentiel bi-invariant sur un groupe réductif G vérifiant la condition de Benabdallah-Rouvière, alors on peut résoudre l’équation différentielle Du=v dans l'espace des distributions G-invariantes (par automorphismes intérieurs) d'ordre fini; nous allons montrer ici que, sous la même hypothèse, on peut résoudre cette équation dans l'espace de toutes les distributions G-invariantes. D'autre part, nous donnons un exemple dans qui montre que les équations différentielles invariantes dans les algèbres de Lie réductives ne sont pas toujours résolubles dans l'espace des fonctions indéfiniment différentiables invariantes. 相似文献
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Wassim Kriaa Kamel Abderrazak Hatem Mhiri Georges Le Palec Philippe Bournot 《Heat and Mass Transfer》2008,44(9):1051-1063
In this work, we propose to study non isothermal air–air coaxial jets with two different approaches: parabolic and elliptic
approaches. The standard k−ε model and the RSM model were applied in this study. The numerical resolution of the equations governing this flow type was
carried out for: the parabolic approach, by a “home-made” CFD code based on a finite difference method, and the elliptic approach
by an industrial code (FLUENT) based on a finite volume method. In forced convection mode (Fr = ∞), the two turbulence models are valid for the prediction of the mean flow. But for turbulent sizes, k−ε model gives results closer to those achieved in experiments compared to RSM Model. Concerning the limit of validity of the
parabolic and elliptic approaches, we showed that for velocities ratio r lower than 1, the results of the two approaches were satisfactory. On the other hand, for r > 1, the difference between the results became increasingly significant. In mixed convection mode (Fr ≅ 20), the results obtained by the two turbulence models for the mean axial velocity were very different even in the plume
region. For the temperature and the turbulent sizes the two models give satisfactory results which agree well with the correlations
suggested by the experimenters for X ≥ 20. Thus, the second order model with σ
t = 0.85 is more effective for a coaxial jet study in a mixed convection mode. 相似文献
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Hamam Abderrazak Maiza Mounira Chehimi Mohamed M. Oukil Dehbia 《Cellulose (London, England)》2022,29(8):4579-4588
Cellulose - In this work, a cellulosic paper substrate (Pap) coated by in situ polymerization of polypyrrole (PPY) was designed. This paper was subsequently coated with silver nanoparticles... 相似文献