The preparation of Ni-Cd ferrite having the chemical formula Ni(1-x)CdxFe2O4 where x varies from 0, 0.1, 0.2, 0.3, 0.4, and 0.5 were synthesized by solid state reaction method. The X-ray analysis shows the existence of single phase spinel structure with increase of lattice parameter and density with increasing Cd contents were as the porosity decreases. The particle size was calculated by X-ray broadening studies. The Vickers hardness of Ni-Cd ferrite system variation between 532 to 568.6. The increase in hardness of composites results from increased Cd-content. The Atomic Force Microscopy (AFM) showed that the average grain size was increases with the increase in Cd content. The variation of dielectric constant, loss tangent and AC conductivity as a function of frequency in frequency range 100Hz-5MHz was studied. The dielectric constants decreases with increasing frequency for all the samples and follow the Maxwell-Wagner's interfacial polarization. The Hall coefficient was found to be positive. It demonstrates that the majority of charge carriers of p-type. The magnetic properties of Ni(1-x)CdxFe2O4 ferrites were strongly affected by the Cd content. The Mossbaure spectra show canted spin structure for all the samples.

In this paper, the structural and optical properties of pure Tin Oxide and doped by Fluorine (F). Thin films were studied prepared by chemical spray pyrolysis on glass substrates at temperature 400oC. The nature of crystallization of the compounds was examined by using X-Ray diffraction technique which showed that the prepared thin films are polycrystalline structure, and the doping processes didn,t show any obvious differences on the crystalline structure of (SnO2). The DC conductivity measurements of the samples were performed by means of a two probe method. The activation energies were computed from the plots of σdc versus 1000/T. To obtain the optical parameters, the absorption and transmittance spectra were recorded in the wave length range 300-1100 nm, the energy gap of the direct and indirect allowed transition were calculated. The optical parameters such as absorption coefficient (α), refractive index (n), extinction coefficient (Ko), dielectric constant (ε'),  and dielectric loss (tanδ), were also investigated.

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