الفهرس 
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Abstract
In this work, NiAl-ferrite/PANI/ x (PANI) nano composite films (x= 0.2, 0.4, 0.6 and 0.8) were prepared using a solution casting process. Films were synthesized to achieve a good magnetic property of polymer and add more conductive properties to NiAlxFe2-xO4. The NiAlxFe2-xO4 (where x= 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00) nanoparticles are synthesized by flash auto combustion method, and polyaniline (PANI) is synthesized by situ-chemical oxidative polymerization method. characterization was carried out by XRD, FTIR, TGA, TEM, EDAX, SEM, and UV-vis to investigate thermal, dielectric and linear -nonlinear optical properties beside to mechanical, dielectric and electrical properties of nanocomposite films. The NiAlxFe2-xO4 nanostructures were characterized by XRD, FTIR, TGA, TEM, EDAX, SEM, and Rietveld refinement using FULLPROF Suite. Dielectric, Electrical, Magnetic, and elastic mechanical, properties of Ni-Al ferrite was studied.
The XRD results and Rietveld refinement of Ni-Al ferrite showed that the lattice contains single phase spinel structure with Fd-3m space group. The average crystallite size was calculated using Debye-Scherer formula and Williamson Hall (W-H) method. The average crystallite size was found to be in the range of 14 – 24.7 nm. Lattice parameter a (Å), cell volume and density were decreased with increasing Al+3 content. Fe, Al and Ni ions dominantly occupy both tetrahedral (A) and octahedral (B) sites. The formation of spinel ferrite confirmed by the two types of stretching vibrations of metal oxide (M-O) bonds. The lower absorption band ʋocta lies in the range of 399-462 cm-1 and the higher absorption band ʋtetra lies in the range of 590-624 cm-1. The morphology of the samples showed the creation of uniform and spherical structural with a narrow size distribution. Mössbauer measurement showed three broad hyperfine magnetic sextets in addition to superparamagnetic doublet were observed in most measured samples. The component with the higher field value is associated with Fe3+ ions at B- site, while that with smaller field is associated with Fe3+ ions at A-site. The third collapse sextet which have smallest field and very broad width represents an intermediate phase between magnetic and superparamagnetic states. The results manifest significant changes in elastic mechanical and electrical properties due to the presence of Al content. With increasing Al content, bulk, B, shear, G, and Young, E, moduli decreased, and stay in the same order of hundreds of GPa range, while the values of Debye temperature, θD, increased.