Abstract
The radiation shielding abilities of waste marbles with different concentrations of WO3 (tungsten oxide) nanoparticles were investigated. Four marbles were prepared with 0, 0.05, 0.1, and 0.2 WO3 nanoparticles. The study aims to investigate the effect of the WO3 concentration, the density, and the particle size of the waste marble samples. The linear attenuation coefficient (LAC) of the S1 sample, the sample with no WO3, was determined theoretically and experimentally, and the results demonstrated that they were close enough together to adequately determine the LAC of the other samples. Additionally, the samples with nano-WO3, rather than micro-WO3, were found to have a greater LAC, showing that decreasing the particle size of the sample improves their shielding ability. Samples with greater WO3 content also had higher LAC values. The LAC of the marbles was also evaluated at a wide energy range (0.015–15 MeV) to examine the shielding properties of the samples for a wide range of applications, and an inverse trend between LAC and energy was observed. The radiation protection efficiency (RPE) of the marbles demonstrated that the marbles absorb almost all incoming photons at low energies. As energy increases, the efficiency of the samples naturally drops, as the photons are able to penetrate through them with greater ease. High energy dependence was found when calculating the half-value layers (HVL) of the samples. When comparing the LAC and mean free paths (MFP) of the marbles, an inverse relationship was observed. Furthermore, the samples with nano-WO3 had a smaller MFP than those with micro-WO3, meaning that decreasing the particle size of the samples improves their radiation shielding ability. The Zeff of the micro-WO3 samples was also determined and the values followed three distinctive trends depending on the energy range of the incoming photons.