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The current investigation focus on synthesize of nano-crystalline mixed ternary transition metal ferrites (MTTMF) through facile hydrothermal method combining post-annealing treatments via tuning the ratio of metallic elements using a nickel foam as the substrate. In this research, different transition metal ferrites of ZnFe 2 O 4 (ZnFe), CoZnFe oxide, CuZnFe oxide, NiZnFe oxide, AlZnFe oxide and MgZnFe oxide have been synthesized. X-ray diffraction analysis was used to characterize phase development occurred in the MTTMF samples. The Morphologies of the prepared materials have been studied by means of field emission scanning electron microscopy and transmission electron microscopy. The electrochemical performance of the electrodes was evaluated using galvanostatic charge-discharge, AC impedance measurement and cyclic voltammetry analysis. ZnFe electrode prepared at 150 °C shows the highest specific capacitance of 1298 F g −1 at 10 mV s −1 scan rate in 1 M KOH aqueous solution. It was concluded that higher annealing temperatures (180 °C) for this electrode resulted in better capacitive behavior with specific capacitance of 1580 F g −1 at a scan rate of 10 mV s −1. These high performance and great capacitive behavior indicated that the ZnFe electrode is a promising material for energy storage devices.

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The composites derived from the bioactive glasses, such as BG/polysulfone, have better mechanical properties and their characteristics are closer to human bone. In this paper, the fracture behavior of 58s BG/PSF composite has been investigated. The extended finite elements method (XFEM) was used as an alternative numerical method to the FEM, in order to model the fracture behavior of 58s BG/PSF composite with greater accuracy. The XFEM doesn’t require remeshing at each step and achieves the precise approximation of singularities by incorporating discontinuity behavior into the elements using enrichment functions. The aim of using the XFEM was to obtain stress intensity factors, displacements, stress and strain around the crack tip, fracture toughness as well as strain energy release rate of BG/polymer composite. Moreover, the 58s BG/PSF composite with 30% volume ratio of bioactive glass particles was synthesized using solvent casting method. Meanwhile, the SEM micrographs were prepared, and the fracture mechanic tests were accomplished based on ASTM D5045 standard test method. The obtained fracture toughness was in the range of 1.4 to 1.6 MPa m , and the strain energy release rate is in the range of 1600 to 1900 J.m−2, which is comparable to the same properties of natural human bone. Also, the stress intensity factors and strain energy release rates were calculated by coding in MATLAB and modeling in ABAQUS, and the numerical results were validated with the analytical and experimental results.

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