MOHAMED Maalmi
معلمي محمد
mohamed.maalmi@univ-msila.dz
0698006306
- Departement of Physics
- Faculty of Sciences
- Grade PHd
About Me
Sciences de la Matière
Filiere
Physique
Applied Physics
Location
Boussada, Boussada
Msila, ALGERIA
Code RFIDE- 1990-10-16 00:00:00
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MOHAMED Maalmi birthday
- 2025-11-20
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2025-11-20
Effect of Temperature on the Formation of Wollastonite Compositions in Sol -Gel Synthesis Processes
In recent decades, wollastonite has emerged as one of the most prominent bioceramic alternatives used in dentistry and orthopedic applications, owing to its chemical and biological composition. The synthesis of wollastonite typically involves three main steps: solution preparation, aging, and subsequent heat treatment at elevated temperatures. Several methods have been developed for the preparation of wollastonite, among which the sol–gel technique stands out due to its numerous advantages, including the ability to produce nanostructured materials with favorable mechanical properties. The synthesis of wollastonite was performed via sol-gel route, using calcium nitrate (Ca(NO₃)₂) as the calcium precursor and tetraethyl orthosilicate (TEOS) as the silicon source. In this study, the solution aging time was fixed at 24 hours, while the aging temperature was varied (50 °C, 70 °C, or 90 °C). Nitric acid was selected as the dissolving medium After heat treatment, the obtained results, using X-ray and infrared spectroscopy, showed the formation of the same phases at each temperature of treatment (800 °C and 1000 °C). The aging temperature only affected the time of the gel formation. The higher aging temperature led to the fast gel formation. This study demonstrates the role of aging temperature on the sol-gel extraction synthesis of wollastonite in shorter time which presents an economic benefit.
Citation
Fatima Zohra MEZAHI , Mohamed Maalmi , ,(2025-11-20), Effect of Temperature on the Formation of Wollastonite Compositions in Sol -Gel Synthesis Processes,2nd National Conference on Physics and its Applications (NCPA'25),Bou-saada
- 2025-11-09
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2025-11-09
Effect of type of solvent on the synthesis of wollastonite by sol-gel route
This study is devoted to study the effect of the nature of solvent on the synthesis of wollastonite (CaSiO3) by sol-gel route. A mixture of ethanol and acid nitric (2 N) with different ratio was used as solvent medium. To study the structural evolution with type of solvent, different techniques were employed as: X- ray diffraction (XRD, Infrared and Raman spectroscopy. The obtained results of the synthesized product showed the formation of larnite at 800 °C for all prepared products. When the synthesized products were thermal treated at 1000 °C, -wollastonite appeared. However, when the volume of ethanol increased, the ratio of larnite decreased and -wollastonite increased. Another phase -wollastonite was appeared. Its ratio was important for 25 and 34 ml of ethanol. These results were consolidated by the dielectric results. The obtained results showed that the type of used solvent has an important effect on the nature of the formed phases and their ratios.
Citation
Fatima Zohra MEZAHI , Mohamed Maalmi , ,(2025-11-09), Effect of type of solvent on the synthesis of wollastonite by sol-gel route,5th International Conference on Mechanics and Materials, ICMM’25,Setif
- 2025-10-29
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2025-10-29
Dielectric Analysis of Wollastonite: Effect of Frequency and Temperature on Electrical Properties
Dielectric analysis is a valuable and versatile method used to examine the electrical behavior of materials through measurement of their response to alternating electric fields at a wide variety of frequencies. The subject of this research is wollastonite (CaSiO3), a calcium silicate ceramic with extensive application as a biomaterial because of its very good biocompatibility and bioactivity. The research evaluates the frequency and temperature dependence of wollastonite's dielectric properties since they are two of the most important parameters that characterize the material's reaction to electrical stimulus in biomedical applications. Furthermore, the current research examines the influence of various solvents used for synthesizing wollastonite on its crystalline phases, which are the decisive factors for its dielectric behavior. Dielectric constant (permittivity) and dielectric loss measurements were collected to reveal structural and phase evolution related to processing conditions and treatment temperatures. Results show the typical decrease of permittivity with increasing frequency, while high temperatures enhance molecular mobility and polarization, increasing dielectric constant at low frequencies. Solvent composition changes during processing yielded distinct phases—mainly β-wollastonite and α-wollastonite—with influence on crystallinity, porosity, and hence electrical properties. These findings are significant as they create a comprehensive understanding of the interrelation between synthesis conditions, microstructure, and dielectric properties. This is crucial for the optimization of wollastonite biomaterials for medical implant, bone graft, and other bioactive device applications where electric field interactions can impact biological response and functional integration. Thus, dielectric analysis emerges as a core method in the design and development of novel biomaterials for enhanced clinical performance and therapeutic outcomes.
Citation
Fatima Zohra MEZAHI , Mohamed Maalmi , ,(2025-10-29), Dielectric Analysis of Wollastonite: Effect of Frequency and Temperature on Electrical Properties,1st National Seminar on Structural Mechanics and Materials (SNMSM’25),M'sila
- 2025-10-21
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2025-10-21
Experimental study of the effect of nitric acid on wollastonite synthesis via sol-gel method
This study is devoted to examine the effect of nitric acid on the synthesis of wollastonite (CaSiO₃) via sol-gel method. This technology allows low-temperature production of powders at nanometer scale and has some benefits compared to conventional techniques [1]. Wollastonite has been used in several biomedical applications such as artificial dental roots and bone filling biomaterial because it is biocompatible and bioactive [2]. Artificial implants based on wollastonite have found wide usage in the field of orthopedics to treat bone deficiencies [3-5]. The bioactivity of wollastonite originates because of the presence of silicon, which facilitates the metabolism of new bone formation. In this study, calcium nitrate (Ca(NO₃)₂) and tetraethyl orthosilicate (C₈H₂₀O₄Si: TEOS) were used as the source of calcium and silicon, respectively. Nitric acid was used as solvent with different concentrations (2, 1.5, 1, and 0.5 M). To analyze the structural evolution of formed phases, different techniques were used: X-ray diffraction (XRD), spectrometer FTIR-ATR, and Raman spectroscopy. Dielectric measurements were also conducted. The obtained results indicated the formation of larnite at 800°C for all products. When the products were heat treated at 1000°C, β-wollastonite was formed. But as the concentration of nitric acid decreased, the proportion of larnite declined, β-wollastonite increased, and a new phase, α-wollastonite, also resulted with an appreciable percentage at 0.5 N concentration of nitric acid. The obtained results showed that the concentration of nitric acid has a major impact on the nature and proportions of the phases formed.
Citation
Fatima Zohra MEZAHI , Mohamed Maalmi , ,(2025-10-21), Experimental study of the effect of nitric acid on wollastonite synthesis via sol-gel method,1st International Hybrid Seminar: Green Chemistry and Artificial Intelligence: Towards Molecular Design,M'sila