الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 75 |  |  |
| | | from | 75 | | |
Abstract
Metal-polymer composites of nano-structural tungsten oxide (WO3) and poly vinyl alcohol (PVA) as filler and base, respectively, were synthe-sized by casting method. The nano tungsten oxide was prepared by precipita-tion method and confirmed by XRD analysis. Also its particle size was de-termined by SEM. The nano composite sheets were prepared with different concentrations of tungsten nanoparticles 25, 50, 70 and 80 wt %. The struc-ture, morphological, thermal and mechanical characteristics of the nanocom-posite sheets were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal analyzer (DTA) and tensile test ma-chine, respectively.
The Gamma-ray attenuation properties of the synthesized nano compo-sites were examined using Gamma-ray spectrometers employing NaI (Tl) detector and Geiger Mullar counter. The Gamma-ray attenuation coefficients of the nono composite sheets were measured as a function of the WO3 con-centrations for Gamma-ray energies 662 and 364 keV of Cs-137 and I-131 sources.
Experimental findings revealed that the prepared composite in nano range and the dispersing of particles in polymer matrix is homogenous. The thermal properties improving by increasing the concentration of WO3 but the tensile properties become little bad by increasing the concentration. The at-tenuation measurements showed that samples with high concentration are more effective in shielding of Gamma-ray. So the characteristics of the WO3/PVA nano composites allow it to be used as an efficient Gamma-ray shielding material.