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Using the auto combustion flash method, Ni1−x+2Mgx+2Fe2+3O4 (x = 0, 0.2, 0.6, 0.8 and 1) nano-ferrites were synthesized. All samples were thermally treated at 973 K for 3 h. The structural analysis for the synthesized samples was performed using XRD, high-resolution transmission electron microscopy (HRTEM), and FTIR. Scanning electron microscopy (SEM) was undertaken to explore the surface morphology of all the samples. The thermal stability of these samples was investigated using thermogravimetric analysis (TGA). XRD data show the presence of a single spinel phase for all the prepared samples. The intensity of the principal peak of the spinel phase decreases as Mg content increases, showing that Mg delays crystallinity. The Mg content raised the average grain size (D) from 0.084 μm to 0.1365 μm. TGA shows two stages of weight loss variation. The vibrating sample magnetometer (VSM) measurement shows that magnetic parameters, such as initial permeability (μi) and saturation magnetization (Ms), decay with rising Mg content. The permeability and magnetic anisotropy at different frequencies and temperatures were studied to show the samples’ magnetic behavior and determine the Curie temperature (TC), which depends on the internal structure. The electrical resistivity behavior shows the semi-conductivity trend of the samples. Finally, the dielectric constant increases sharply at high temperatures, explained by the increased mobility of charge carriers, and decreases with increasing frequency.

Laser light scattering Scattering parameter Polyvinyl alcohol Zimm plot a b s t r a c t Static laser scattering (SLS) is one of the most efficient techniques used for the molecular weight determination of polymer. Among of all polymers, polyvinyl alcohol (PVA) polymer was selected. A polystyrene (PS) was used as a standard polymer. A polyvinyl alcohol was investigated for its importance in pharmaceutical, biomedical, and industrial applications.Different concentrations in the range (3e9) Â 10 À3 g mL À1 were prepared. SLS data were obtained by using a self-built of the laser scattering system. The angular behavior of those selected polymer solutions with different concentrations were studied by plotting the intensity of the scattered light against the scattering angle in the range of 40e140 . By using Zimm plot the weight-average molecular weight M w , radius of gyration R G, and second virial coefficient A 2 of the standard PS and PVA were determined.