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In this study, the bioactivity of CaSiO3 and Porecalin-CaSiO3 composites have been investigated utilizing X-ray diffraction (XRD) and scanning electron microscopy-Energy-dispersive X-ray spectroscopy (SEM-EDS). CaSiO3 and P-CaSiO3 are prepared by Sol-Gel method for different weight percentages of CaSiO3 (P90CS10, P80CS20 and P70CS30 wt. %). The in vitro bioactive properties have been carried out by immersed the powder and sintered samples on different compositions in simulated body fluids at 32 day to evaluate their bioactivity. Ca/P ratio have been calculated through EDS measurements. Structural characterization revealed the amorphous phase of CaSiO3 when heated at 700 °C and phase transition to the crystalline phase when heated at 950 °C, where pseudowollastonite (α-CaSiO3) and Ca2(SiO4) phases have been appeared. CaSiO3 showed better bioactive ability in comparison with its composites. In general, the bioactivity increases with increasing the CaSiO3 time of immersion in stimulated body fluid (SBF). The closest value to the stoichiometric hydroxyapatite, Ca10(PO4)6(OH)2 has been observed with P70CS30 sintered specimen where Ca/P was 1.694.

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In this study, improving the mechanical properties of Porcelain-CaSiO3 bioactive composites has been investigated by X-ray diffraction (XRD), flexural strength, and Vickers microhardness tester. Preparing the porcelain-CaSiO3 composite has been done using the sol-gel method from Si(OC2H5)4, Ca (NO3)2.4H2O as starting materials and HNO3 used as a catalyst and mixed the sol of CaSiO3 with Porcelain IPS inline powder with three different weight percentages of CaSiO3 (P90CS10, P80CS20 and P70CS30 wt. %). Structural characterization revealed the amorphous phase of CaSiO3 when heated at 700 °C and phase transition to the crystalline phase when heated at 950 °C, where pseudowollastonite (α-CaSiO3) and Ca2(SiO4) phases have appeared. Concerning the mechanical properties, flexural strength, and Vickers microhardness for porcelain-CaSiO3 composites were increased with increasing CaSiO3 content in the composites. The maximum values of flexural strength and Vicker microhardness were recorded at P70CS30, and they were 99.85 MPa and 1604 MPa, respectively.

Calixarenes are a group of materials that are widely used for gas sensing studies because of their simple synthesis, conformational flexibility, binding group tunability, variability in their cavity sizes and improved selectivity to different gas molecules. In recent years it has been shown that incorporation of gold nanoparticles (AuNPs) into organic layers further enhances their gas sensing performance. The present study reports on the fabrication of thin films of calixarene and AuNPs using Langmuir-Schaefer (LS) methods. The gas sensing properties of the produced films are investigated on exposure to saturated vapours of volatile organic compounds (VOCs) using surface plasmon resonance as an optical detection technique. Multilayers comprising films of AuNPs and calixarene have been investigated to evaluate the effect of AuNPs on the films sensing performances. It has been demonstrated that the hybrid layers exhibited improved sensing performance in terms of the degree of their response.