Magnetite nanoparticles have been synthesized by a green method. For this process, ferricchloride hexahydrate, ferrouschloride tetrahydrate (2/1 molar ratio) solution was mixed with different amounts of carob leaves extract and NaOH solution was added to get pH(2, 5,8 and 11) heated for 30 min at (30,60,80 and 100) °C . In this report, a description was introduced for the synthesis of Fe304 nanoparticles (NPs) in order to obtain the optimum (pH8 ,temperature and amount of extract) that have small particle size MNPs. The magnetite nanoparticles were characterized by UV-Vis absorption spectroscopy, through Field emission scanning electron microscopy (FESEM) and Atomic Force Microscope (AFM). In UV-Vis spectroscopy, the absorbance of surface plasmon resonance (SPR) of magnetite nanoparticles synthesized with different parameters, were observed a single visible peak located in the range of (290-519) nm and it was related to spherical monodisperse, peak shifts to shorter wavelength (blue shift) with change parameter. FESEM images confirm the Fe304 NPs synthesized with different parameters were spherical shaped and lower than 50 nanoscale. AFM images of magnetite nanoparticles with different parameter. It is observed that each nucleus magnetite Nanoparticles is spherical in geometry

D.c. σ(0) and a.c conductivity σ(w) and dielectric parameter ( and tan 60 Te 30 Ge 10 glassy thin films which were prepared by thermal evaporation were investigated. Measurements of a.c. conductivity over frequency range (100Hz-100kHz) and temperature range (303-363K) showed that the a.c. conductivity follows the empirical formula  a.c (w)=Aw s , where (s) lies between (1.03-0.60).In the glasses of Se 60 Te 30 Ge 10 thin films the d.c. conductivity along localized states prevails. A.c conductivity is explained by hopping mechanism of charge transfer between two defect centers.

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CdTe Thin films were deposited by thermal evaporation on glass substrates under vacuum of 2×10 -6 mbar. The annealing has been done under vacuum 10 -3 mbar at (303,373,423,473) K annealing temperature. The structure was investigated by XRD technique. It is found that the structure for all samples (as-deposited and annealed) is polycrystalline. The d.c. electrical conductivity was investigated and attributed to two mechanisms. The activation energy Ea increases from 0.13 to 0.55eV as annealing temperature increases from 303 to 473K. The a.c. conductivity reveals that the dependence of activation energy Ew on frequency is larger than that on temperature. Ew increases from 0.11 to 0.18eV as annealing temperature increases from 303 to 473K. Optical studies showed that optical energy gap increases with increasing annealing temperature from 1.4eV at 303K to 2.15eVat 473K.Keyword : CdTe thin films , electrical and optical properties of CdTe thin films.

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