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21.
Fares Zouaoui Saliha Bourouina-Bacha Mustapha Bourouina Nadia Zine Abdelhamid Errachid Nicole Jaffrezic-Renault 《Molecules (Basel, Switzerland)》2022,27(2)
The massive and careless use of glyphosate (GLY) in agricultural production raises many questions regarding environmental pollution and health risks, it is then important to develop simple methods to detect it. Electrochemical impedance spectroscopy (EIS) is an effective analytical tool for characterizing properties at the electrode/electrolyte interface. It is useful as an analytical procedure, but it can also help in the interpretation of the involved fundamental electrochemical and electronic processes. In this study, the impedance data obtained experimentally for a microsensor based on molecularly imprinted chitosan graft on 4-aminophenylacetic acid for the detection of glyphosate was analyzed using an exact mathematical model based on physical theories. The procedure for modeling experimental responses is well explained. The analysis of the observed impedance response leads to estimations of the microscopic parameters linked to the faradic and capacitive current. The interaction of glyphosate molecules with the imprinted sites of the CS-MIPs film is observed in the high frequency range. The relative variation of the charge transfer resistance is proportional to the log of the concentration of glyphosate. The capacitance decreases as the concentration of glyphosate increases, which is explained by the discharging of the charged imprinted sites when the glyphosate molecule interacts with the imprinted sites through electrostatic interactions. The phenomenon of adsorption of the ions in the CMA film is observed in the low frequency range, this phenomenon being balanced by the electrostatic interaction of glyphosate with the imprinted sites in the CS-MIPs film. 相似文献
22.
Boutaka Rabeh Liang Dawei Bouadjemine Rochdi Traiche Mohammed Kellou Abdelhamid 《Journal of Russian Laser Research》2021,42(4):453-461
Journal of Russian Laser Research - Laser side-pumping approach is an extremely attractive configuration for many laser applications. Through this approach, the laser beam can be generated in the... 相似文献
23.
2-(5-Methyl-1-phenyl-1H-pyrazol-4-yl)-2-oxo-N′-phenylaceto-hydrazonoyl bromide was synthesized and used as precursor for synthesis of some new 1,3,4-thiadiazoles, pyrrolo[3,4-c]pyrazoles, and 1,2,4-triazolo[4,3-a]pyrimidines. The mechanisms that account for formation of products were discussed. Also, the structures of all the newly synthesized products were confirmed based on elemental analysis, spectral data and by alternative methods. 相似文献
24.
Sahar Raissi Mohamed Kadri Younes Abdelhamid Ghorbel François Garin 《Journal of Sol-Gel Science and Technology》2010,53(2):412-417
Catalysts based on chromium supported by sulphated and unsulphated zirconia have been synthesised, in one step, by sol–gel
method and dried in hypercritical solvent conditions. Comparative study of their catalytic properties shows that dispersed
Cr3+ seems to be the active species in the n-hexane aromatisation reaction. However, the acidity generated by sulphate groups acts as coke eliminator of the layers deposed
on the surface mainly when catalyst is calcined at high temperature. 相似文献
25.
26.
Tailoring of carboxyl‐decorated magnetic latex particles using seeded emulsion polymerization
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Talha Jamshaid Mohamed M. Eissa Quentin Lelong Anne Bonhommé Geraldine Augsti Nadia Zine Abdelhamid Errachid Abdelhamid Elaissari 《先进技术聚合物》2017,28(9):1088-1096
In this research, submicron and carboxyl‐functionalized magnetic latex particles were elaborated by using seeded emulsion polymerization technique in presence of oil‐in‐water (o/w) magnetic emulsion as seed. The polymerization conditions were optimized in order to get well‐defined latex particles with magnetic core and polymer shell bearing carboxylic (–COOH) functionality. Starting from (o/w) magnetic emulsion as seed, synthesis process was performed by copolymerization of styrene (St) monomer with the cross‐linker divinylbenzene (DVB) in presence of 4,4′‐azobis(4‐cyanopentanoic acid) (ACPA) as a carboxyl‐bearing initiator. The prepared magnetic latex particles were first characterized in terms of particle size, chemical composition, morphology, magnetic properties, magnetic content, and colloidal stability using various techniques, e.g. particle size analyzer using dynamic light scattering (DLS) technique, Fourier transform infrared, transmission electron microscopy, vibrating sample magnetometer, thermogravimetric analysis, and zeta potential measurements as a function of pH of the dispersion media, respectively. The prepared magnetic latex particles were then used as second seed for further functionalization with methacrylic acid (MAA) in order to enhance carboxylic groups on the magnetic particle's surface. The results showed that final magnetic latex particles possessed spherical morphology with core‐shell structure and enriched carboxylic acid functionality. More importantly, they exhibited superparamagnetism with high magnetic content (58.42 wt%) and high colloidal stability, which considered as the main requirements for their application in the biomedical diagnostic domains. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
27.
Heydari-Gorji A Belmabkhout Y Sayari A 《Langmuir : the ACS journal of surfaces and colloids》2011,27(20):12411-12416
Poly(ethyleneimine) (PEI) supported on pore-expanded MCM-41 whose surface is covered with a layer of long-alkyl chains was found to be a more efficient CO(2) adsorbent than PEI supported on the corresponding calcined silica and all PEI-impregnated materials reported in the literature. The layer of surface alkyl chains plays an important role in enhancing the dispersion of PEI, thus decreasing the diffusion resistance. It was also found that at low temperature, adsorbents with relatively low PEI contents are more efficient than their highly loaded counterparts because of the increased adsorption rate. Extensive CO(2) adsorption-desorption cycling showed that the use of humidified feed and purge gases affords materials with enhanced stability, despite limited loss due to amine evaporation. 相似文献
28.
Adsorption of CO2, N2, CH4 and H2 on triamine-grafted pore-expanded MCM-41 mesoporous silica (TRI-PE-MCM-41) was investigated at room temperature in a wide
range of pressure (up to 25 bar) using gravimetric measurements. The material was found to exhibit high affinity toward CO2 in comparison to the other species over the whole range of pressure. Column-breakthrough dynamic measurements of CO2-containing mixtures showed very high selectivity toward CO2 over N2, CH4 and H2 at CO2 concentrations within the range of 5 to 50%. These conditions are suitable for effective removal of CO2 at room temperature from syngas, flue gas and biogas using temperature swing (TS) or temperature-pressure swing (TPS) regeneration
mode. Moreover, TRI-PE-MCM-41 was found to be highly stable over hundreds of adsorption-desorption cycles using TPS as regeneration
mode. 相似文献
29.
Hnaien M Lagarde F Bausells J Errachid A Jaffrezic-Renault N 《Analytical and bioanalytical chemistry》2011,400(4):1083-1092
Trichloroethylene (TCE), a suspected human carcinogen, is one of the most common volatile groundwater contaminants. Many different
methodologies have already been developed for the determination of TCE and its degradation products in water, but most of
them are costly, time-consuming and require well-trained operators. In this work, a fast, sensitive and miniaturised whole
cell conductometric biosensor was developed for the determination of trichloroethylene. The biosensor assembly was prepared
by immobilising Pseudomonas putida F1 bacteria (PpF1) at the surface of gold interdigitated microelectrodes through a three-dimensional alkanethiol self-assembly
monolayer/carbon nanotube architecture functionalised with Pseudomonas antibodies. The biosensor response was linear from 0.07 to 100 μM of TCE (9–13,100 μg L−1). No significant loss of the enzymatic activity was observed after 5 weeks of storage at 4 °C in the M457 pH 7 defined medium
(two or three measurements per week). Ninety-two per cent of the initial signal still remained after 7 weeks. The biosensor
response to TCE was not significantly affected by cis-1,2-dichloroethylene and vinyl chloride and, in a limited way, by phenol. Toluene was the major interference found. The bacterial
biosensor was successfully applied to the determination of TCE in spiked groundwater samples and in six water samples collected
in an urban industrial site contaminated with TCE. Gas chromatography–mass spectrometric analysis of these samples confirmed
the biosensor measurements. 相似文献
30.
Nasser Eddine Mouhoub Abdelhamid Benhocine Hocine Belouadah 《Applied Mathematical Modelling》2011,35(9):4575-4588
A project is an enterprise consisting of several activities which are to be carried out in some specific order. The activities and the order in which they need to be carried out can be represented by a PERT network. The PERT technique is a traditional, well-known approach to the expert of project management. When networks are used, it often becomes necessary to draw dummy activities. Since the computation of project completion time is proportional to the number of arcs, including dummy arcs, it is desirable to draw a network with as few dummy activities as possible.In this paper, we propose a new method for constructing, for a given project scheduling problem, a PERT network having as small as possible the number of dummy arcs by using some results on line graphs. This algorithm deals with the existence of transitive arcs. The paper contains illustrative examples, proofs of some theoretical results as well as a comparative study with a similar algorithm known in the literature. Computational results showed the superiority of our algorithm. 相似文献