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Your search keyword '"Bensaid, Samir"' showing total 276 results
Start Over Author "Bensaid, Samir" Publication Type Academic Journals
276 results on '"Bensaid, Samir"'

46. Mesoporous Ceria and Ceria‐Praseodymia as High Surface Area Supports for Pd‐based Catalysts with Enhanced Methane Oxidation Activity.

Author

Ballauri, Sabrina, Sartoretti, Enrico, Castellino, Micaela, Armandi, Marco, Piumetti, Marco, Fino, Debora, Russo, Nunzio, and Bensaid, Samir

Abstract

In recent years, Pd/CeO2 materials have proven to be effective catalysts for the total oxidation of methane. In this work, three different synthesis routes were used to prepare high specific surface area supports, consisting of pure CeO2 and 10 at% Pr‐doped ceria (Ce90Pr10). Nano‐structured spheres were obtained with a microwave‐assisted synthesis, dumbbell‐like particles were produced through a urea‐based hydrothermal method, and ordered mesoporous oxides were prepared by using SBA‐15 as hard‐template. The six materials were then impregnated with 2 wt% Pd, calcined at 500 °C, and comprehensively characterized. All the samples retained their high surface area after impregnation (75–110 m2 g−1), allowing a good dispersion of palladium. No significant structural or morphological differences were observed upon Pr doping, but a higher Pd oxidation state was induced by Pr‐doped supports. However, all Pd/CeO2 and Pd/Ce90Pr10 catalysts exhibited similar activity for dry methane oxidation below 500 °C, regardless of the synthesis technique and of the Pr presence: they all achieved almost complete CH4 oxidation at 400 °C, showing a really remarkable improvement with respect to analogous low surface area supports. A promoting role of Pr was instead noticed in wet conditions, thanks to its ability to counteract water‐induced deactivation phenomena. [ABSTRACT FROM AUTHOR]

Published
2024
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47. Fast and efficient inversion methods for crack sizing using Bz magnetic signature.

Author

Barrarat, Fatima, Bensaid, Samir, Rayane, Karim, Helifa, Bachir, Lefkaier, Iben Khaldoun, and Zorig, Assam

Subjects
*SIGNAL generators, *DATABASES
Abstract

Fast estimation is a critical feature of the proposed modeling approach as a "forward" fast solver that has a key role in solving the "inverse" problem involved in crack sizing, especially for real‐time applications. To this end, two different inversion methods have been proposed to estimate the crack depth. The first one uses an interpolation model of the 3D direct model simulation data. The second approach is based on artificial neural networks (ANN). In this article, the rotating uniform eddy current (RUEC) probe is used to detect the normal magnetic component Bz which is defined as the characteristic signal for reconstructing the crack length and depth concurrently. Using the first approach, The Bz characteristic 3D surface is presented, and this can be modeled by a fitted polynomial interpolation equation. Thus, the crack depth can be inverted using this equation referring to the experimental or simulated Bz signal and the crack length. The ANN is outlined to determine the crack depth based on the simulated Bz signature. The move from the first inversion method to the second was flexible and useful, in which the interpolation model is used as a defect signal generator for fast building of a large and efficient database for ANN training. Both of the proposed methods proved the objectivity and accuracy of the inversion results and offered more robust engineering support for automated NDT, reducing production time and increasing productivity. [ABSTRACT FROM AUTHOR]

Published
2024
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48. Aqueous Phase Reforming of Dairy Wastewater for Hydrogen Production: An Experimental and Energetic Assessment.

Author

Pipitone, Giuseppe, Pirone, Raffaele, and Bensaid, Samir

Abstract

The treatment of dairy industry effluents poses a significant challenge from the environmental point of view because of its high organic load. In this work, the aqueous phase reforming of lactose was investigated as a representative model compound for the production of renewable hydrogen. The tests were conducted using two different scenarios: the first one is referred to as direct aqueous phase reforming (APR); the second one proposed a pre-hydrogenation step, followed by APR. The implementation of this reactive pretreatment allowed for minimizing the solid by-product formation with respect to the direct APR, where most of the initial carbon ended up as solid residue. The pre-hydrogenation was investigated in the range of 180–220 °C, using Ru-based catalysts. In the best scenario (using 5% Ru/C), the carbon to solid was reduced by 95%, and up to 70% of the initial carbon was converted into gaseous compounds, hence contributing to the removal of the organic content of the wastewater while producing an energy carrier. Moreover, the hydrogen selectivity increased up to 70% (with respect to 2.5% for direct APR), thanks to hindering homogeneous reaction pathways that do not lead to hydrogen production. Finally, an energetic analysis was conducted to assess the possibility of coupling the APR with the dairy industry and quantifying the percentage of energy which may be produced in situ to satisfy industrial duties. [ABSTRACT FROM AUTHOR]

Published
2024
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