MAHMOUD Lebid

TALHI SOUAD

Etude de l’influence des conditions de synthèses sur les propriétés physicochimiques d’un oxyde mixte à base du lanthane, cuivre et cobalt.

GHAZEL. Nahed , HARKAT. Hind

Etude de I'influence des conditions de synthèses sur les propriétés physicochimiques d'un oxyde mixte LaFeOr.

Touafek Mohamed Akram , Touama Mahmoud

Synthèse et étude électrochimique d'un oxyde mixte à base de lanthane et d'aluminium.

BEZAF WARDA , GUERSSAS WASSILA, CHEBABHA WARDA

Synthèse et caractérisation physicochimique de la pérovskite LaAlO3

Benchaabane Souhila , Salmi Soumia

Soutenu devant le jury composé de: Ben yahia. Azzedtne Lebid. Mahmoud Berarma. Khadidja Université Université Université M'sila. M'sila. M'sila. Président Rapporteur Examinateur lr..Idïd, Synthèse et Caractérisation physicochimiques De la pérovskite LaFeO

This work envisages the use of perovskite-type materialsas anodes for extractive metallurgical processes. The LaAlO3 is identified to thrive as a suitable electrode for O2 evolution in alkaline system due to its high electronic conductivity and thermal stability. It is a p-type semiconductor catalytic material of perovskite structure (ABO3). Its gas sensing properties, especially for toxic and noxious gases of NO2 and CO are reported. Although, there are many studies of preparation of LaAlO3 oxides, few works have been carried out on the effect of the calcined temperature on the processes of formation of perovskite-like LaAlO3 nanocrystals, structural and electrochemical properties of LaAlO3 oxides. In our present work, lanthanum Aluminum has been synthesized by the citric acid sol–gel method using absolute alcohol as solvent and characterized for its physicochemical properties. The effect of the calcined temperature on the phase formation processes, particle size and electrochemical performance of this material is presented.

Citation

Mahmoud Lebid , ,(2023-10-23), Physico-chemical properties of LaAlO3 catalysts prepared via Sol–Gel method,1 er international seminar on chemical processes and sustainable developement ISCPSD 23,Skikda

In this work, two types of solvents ethanol or water were used in preparation of the LaFeO3 catalysts by citrate sol gel method. The obtained samples were subjected to various calcination temperatures in order to study the catalytic activity and stability for methanol electro-oxidation by XRD, cyclic voltammetry and chronoamperometry. The crystallinity of the LaFeO3 phase in both cases is improved with increasing calcination temperature. The samples prepared using ethanol exhibit higher catalytic properties than those prepared in water for different calcination temperatures. Moreover, the catalyst prepared in ethanol and calcined at 1050 °C, exhibits a high catalytic activity in methanol electro-oxidation and is ~ two times greater than that obtained at 750 °C. Keywords: LaFeO3; Solvent effect ; Calcination temperature ; Methanol oxidation.

Citation

Mahmoud Lebid , ,(2023-10-10), Effects of the Solvent and Calcination Temperature on LaFeO3 Catalysts for Methanol Oxidation,International Conference of Nanotechnology for Environmental Protection & Clean Energy ICNEP 2023,Constantine

As mass production has migrated to developing countries, European and US companies are forced to rapidly switch towards low volume production of more innovative, customized and sustainable products with high added value. To compete in this turbulent environment, manufacturers have sought new fabrication techniques to provide the necessary tools to support the need for increased flexibility and enable economic low volume production. One such emerging technique is Additive manufacturing (AM). AM is a method of manufacture which involves the joining of materials, usually layer-upon-layer, to create objects from 3D model data. The benefits of this methodology include new design freedom, removal of tooling requirements, and economic low volumes. AM consists of various technologies to process versatile materials, and for many years its dominant application has been the manufacture of prototypes, or Rapid prototyping. However, the recent growth in applications for direct part manufacture, or Rapid Manufacturing, has resulted in much research effort focusing on development of new processes and materials. This study focuses on the implementation process of AM and is motivated by the lack of socio-technical studies in this area. It addresses the need for existing and potential future AM project managers to have an implementation framework to guide their efforts in adopting this new and potentially disruptive technology class to produce high value products and generate new business opportunities. Selected applications demonstrate how polymer-based AM is being exploited in lightweight engineering, architecture, food processing, optics, energy technology, dentistry, drug delivery, and personalized medicine. Unparalleled by metals and ceramics, polymer-based AM plays a key role in the emerging AM of advanced multifunctional and multimaterial systems including living biological systems as well as life-like synthetic systems. Keywords : AM Additive manufacturing ; low volume production ; RP Rapid Prototype .

Citation

Mahmoud Lebid , ,(2023-05-18), Bibliographic study in Additive Manufacturing,Advances In Additive Manufacturing AIAM'2023,tunisie à Hammamet

Researchers are showing increasing interest in plant fiber reinforced composites due to their eco-friendliness, low density, low cost and amazing mechanical properties. However, some challenges remain for researchers in this field, most notably poor adhesion between the polymer matrix and the plant fibers, which reduces the mechanical properties of composites reinforced with these fibers. This study aims to improve the adhesion between the matrix and the reinforcement by chemically treating Alfa fibers (Stipa tenacissima) with a 3 wt% NaOH solution at different times (1, 3, 5 and 24 h). FTIR, DRX, GTA and tensile tests were conducted. XRD tests showed that the crystallinity index of 3% alkali treated Alfa fibers for 5 h increased by 36.26%, compared to that of untreated fibers. The results also revealed that the mechanical properties of composites reinforced with treated fibers outperformed those reinforced with untreated fibers. These findings can contribute to the development of high mechanical performance composites, which can be competitive with those prepared with synthetic fibers. Keywords: composite, Stipa tenacissima, adhesion, tensile strength, alkaline treatment

Citation

AZZEDINE Melouki , Azzedine BENYAHIA , Chouki FARSI , Nadir DEGHFEL , Nouri LAIB , Mahmoud Lebid , , (2023), EFFECT OF ALKALINE TREATMENT ON MECHANICAL PROPERTIES OF ALFA FIBER/UNSATURATED POLYESTER COMPOSITE, Cellulose Chemistry and Technology, Vol:57, Issue:5, pages:607-615, Cellulose Chemistry and Technology

In this work, two types of solvents ethanol or water were used in preparation of the LaFeO3 catalysts by citrate sol gel method. The obtained samples were subjected to various calcination temperatures in order to study the catalytic activity and stability for methanol electro-oxidation by XRD, cyclic voltammetry and chronoamperometry. The crystallinity of the LaFeO3 phase in both cases is improved with increasing calcination temperature. The samples prepared using ethanol exhibit higher catalytic properties than those prepared in water for different calcination temperatures. Moreover, the catalyst prepared in ethanol and calcined at 1050 °C, exhibits a high catalytic activity in methanol electro-oxidation and is ~ two times greater than that obtained at 750 °C.

Citation

Mahmoud Lebid , , (2016), Effects of the Solvent and Calcination Temperature on LaFeO3 Catalysts for Methanol Oxidation, Iran .J.Chem.Chem.Eng, Vol:35, Issue:3, pages:75-81, Iran .J.Chem.Chem.Eng

in this work two types of solvents ethanol or water were used in preparation of the LaFeO3 catalysts by citrate sol gel method ;the obtained samples were subjected to various calcination temperatures in order to study the catalytic activity and stability for methanol electro-oxydation by XRD ; cyclic voltammetry and chronoamperometry , the crystallinity of the LaFeO3 phase in both cases is improved with increasing calcination temperature , the samples prepared using ethanol exhibit higher catalytic properties than those prepared in water for different calcination temperatures , moreover ; the catalyst prepared is ethanol and calcined at 1050° C ; exhibits a high catalytic activity in methanol electro-oxidation and is about two times greater than that obtained at 750° C

Citation

Mahmoud Lebid , ,(2015), effects of the solvent and calcination temperature on LaFeO3 catalysts for Metahanol oxidation,journeés internationales de cinétique catalyse et calorimétrie,USTHB ALGER

in this study , LaFeO3 oxides were prepared by critic acid sol-gel method , the samples were subjected to various calcination temperatures in order to investigate the physicochemical properties of the oxide affected by the parameter , samples were characterized by XRD , TG/DTA , IR , laser granulometry and cyclic voltammetry , by imposing various calcination temperatures , phase evolutions were observed , however , the calcination temperature affects significantly the particle size and catalytic activity of the oxide at higher temperature , Oxygen evolution shows that the current density at 1,050°C is five times greater than at 950°C From these results , the best calcination temperature can be chosen to arrive at the effective catalyst necessary for the desired catalytic reaction

Citation

Mahmoud Lebid , ,(2014), Physico-chemical properties of LaFeO3 catalysts prepared via sol-gel Method,1st inetrnational conference on materials for energy & Environmental engineering -ICM3E'14,Hilton Hotel , algiers _algeria

in this study , LaFeO3 oxides were prepared by critic acid sol-gel method , the samples were subjected to various calcination temperatures in order to investigate the physicochemical properties of the oxide affected by the parameter , samples were characterized by XRD , TG/DTA , IR , laser granulometry and cyclic voltammetry , by imposing various calcination temperatures , phase evolutions were observed , however , the calcination temperature affects significantly the particle size and catalytic activity of the oxide at higher temperature , Oxygen evolution shows that the current density at 1,050°C is five times greater than at 950°C From these results , the best calcination temperature can be chosen to arrive at the effective catalyst necessary for the desired catalytic reaction

Citation

Mahmoud Lebid , , (2014), Synthesis and Electrochemical properties of LaFeO3 Oxides prepared via Sol-gel Method, ARABIAN JOURNAL FOR SCIENCE and ENGINEERING, Vol:39, Issue:1319, pages:147-152, springer