IN THE present study, Nickel oxide (NiO) nanoparticles (NiONPs) were bio-synthesized extracellularly by the fungus Fusarium verticillioides (F. verticillioides) using Nickel Nitrate Hexahydrate Ni(NO 3 ) 2 .6H 2 O as a starting material. The formed NiONPs were precipitated in the form of a dark precipitate after adding the fungal filtrate to Ni(NO 3 ) 2 .6H 2 O solution. The properties of this formed precipitate were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transformed infrared (FTIR). The XRD pattern indicated that the NiONPs had a face-centered cubic (FCC) structure and their average crystallite size was found to be 8-17.7 nm. The average particle size found to be 8.5-20.7 nm from TEM image, which was compatible with XRD result. The FTIR analysis bands revealed the chemical composition bonding of the formed nano-NiO compound.The antifungal activity of the formed NiONPs was tested against some human pathogenic fungi which were isolated from mycotic keratitis patients, inpatient department of ophthalmology hospital, Tanta University, Egypt. The best results obtained against Candida albicans, C. tropicalis and Aspergillus niger where the minimum inhibitory concentration (MIC) was 12.5, 25 and 25 mg/ml, respectively. Further confirmation of NiONPs biological activity was employed by measurement of their concentration at different intervals within skin, blood and liver of experimental animals, showing a promising absorption and washing out rates from mice tissues; these results indicated that the NiONPs did not accumulated within mice bodies.

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Three series of Mo doped YBCO have been prepared by conventional ceramic technique. The samples were prepared according to the formulae Y 1-x Mo x Ba 2 Cu 3 O 7-δ , Y Ba 2-x Mo x Cu 3 O 7-δ , Y Ba 2 Cu 3-x Mox O 7-δ and x = 0.0,02,05,08 0.1,0.15,and 0.3. The samples have been prepared at four different oxygenation conditions by the subjection to four oxygenation cycles. The prepared samples have been studied by the four probe method and x-ray measurements. The results declared that Tc is inversely proportional to the square of the distance between doping position and the nearest chain. The width of the transition temperature ∆ Tc was also correlated with a solid angle its vertex on the doping position and its base is the area between the two chains. These results were attributed to the modification occurred by Mo ion to the internal crystal field. In case of Cu series the results indicated that Mo ions substituted Cu in Cu 2 position. Mo incorporated in YBCO as Mo 4+ and Mo 6+ at lower and higher oxygenation conditions respectively. In case of Ba series Mo 4+ and Mo 6+ states seems to be nearly equal. This was attributed to the lower density of oxygen ions around Ba position in comparison with Y and Cu 2 positions.

The (XRD) patterns of the samples Ni0.5Zn0.5Fe2O4 in the form of powder were prepared using the ball milling technique for 41, 67 and 90 hours and were annealed at 1073, 1273 and 1373 K and (Poly vinylidine Fluoride) (PVDF) and composite samples of x% Ni0.5Zn0.5Fe2O4/PVDF, (x% = 5, 10, 15, 20 and 25%) have been studied. The α phase decrease and β-phases increase by increasing the ferrite content suggesting less crystallinity producing an amorphous structure of PVDF at x = 25% ferrite where as β PVDF nucleates in the composites The electric polarization increases by increasing NZF content. The transition from ferromagnetic (order state) to paramagnetic (disorder state) occurs at Curie temperature TC (600K). The DC resistivity is nearly constant from 153k to 286k for all composite samples and then decreases at high temperature. The behavior of dielectric constant and dielectric loss was measured in the temperature range from 200K to 700K. With the increase of magnetic content, the saturation magnetization (Ms) value of the composites also increases.