الفهرس | Only 14 pages are availabe for public view |
Abstract In this thesis, high density polyethylene (HDPE) matrix filled with micro-sized and nano-sized Cadmium Oxide (CdO), Lead Oxide (PbO) and a mixture of both at different concentrations were prepared by compression molding technique. The main objective of this study is mainly directed on the investigation of the pure HDPE, micro CdO/HDPE composites, nano CdO/HDPE composites, micro PbO/HDPE composites, nano PbO/HDPE composites, mixed micro CdO and micro PbO/HDPE composites and mixed nano CdO and nano PbO/HDPE as efficient shielding protective materials for the attenuation of neutrons and gamma-radiation. The mass and linear attenuation coefficients of pure HDPE, microcomposites and nanocomposites were evaluated at photon energies ranging from 59.53 keV to 1408.01 keV using standard radioactive point sources [241Am, 133Ba, 137Cs, 60Co and 152Eu]. Adding micro and nano particles to the HDPE matrix clearly increases the mass attenuation coefficients of the composites and the improvement is more significant at low γ-ray energies. The effect of particle size of the filler has an important role on the shielding ability of the composite. |