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In an attempt to reutilize marble waste, a new approach is presented in the current study to promote its use in the field of shielding against ionizing radiation. In this study, we aimed to develop a novel and sustainable/eco-friendly lead-free radiation shielding material by improving artificial marble (AM) produced from marble waste combined with polyester by reinforcing it with bismuth oxide (Bi2O3) nanoparticles. Six samples of AM samples doped with different concentrations ( 0 % ,   5 % ,   10 % ,   15 % , 20 % , and 25 % ) of Bi2O3 nanoparticles were prepared. The linear attenuation coefficient ( L A C ) values were measured experimentally through the narrow beam method at different energies (0.0595   M e V , 0.6617   M e V , 1.1730   M e V , and 1.330   M e V ) for all samples with various concentrations of Bi2O3. Radiological shielding parameters such as half value layer ( H V L ), tenth-value layer ( T V L ), and radiation shielding efficiency ( R S E ) were estimated and compared for all the different samples. The results prove that increasing the concentration of Bi2O3 leads to the enhancement of the radiation shielding properties of the AM as a shielding material. It was observed that as the energy increases, the efficiency of the samples falls. High energy dependence was found when calculating the H V L and T V L values of the samples, which increased with increases in the energy of the incident photons. A comparison between the sample with the most efficient gamma radiation attenuation capability (AM- 25 % ), concrete, and lead was conducted, and a discussion regarding their radiation shielding properties is presented herein. The results show that the AM- 25 % sample is superior to the ordinary concrete over all the studied energy ranges, as evidenced by its significantly lower H V L s . On the contrary, lead is superior to the AM- 25 % sample over all the studied energy ranges owing to its unbeatable density as a shielding material. Overall, this new type of artificial marble has the potential to be used as a radiation shielding material at low- to medium-gamma energy regions, specifically in medical imaging and radiation therapy. [ABSTRACT FROM AUTHOR]

We developed new composites for photons shielding applications. The composite were prepared with epoxy resin, red clay and bismuth oxide nanoparticles (Bi2O3 NPs). In order to establish which ratio of red clay to Bi2O3 NPs provides the best shielding capabilities, several different ratios of red clay to Bi2O3 NPs were tested. The transmission factor (TF) was calculated for two different thicknesses of each sample. From the TF data, we found that epoxy resin materials have a high attenuation capacity at low energy. For ERB-10 sample (40%Epoxy + 50% Red clay + 10% Bi2O3 NPs), the TF values are 52.3% and 14.3% for thicknesses of 0.5 and 1.5 cm (at 0.06 MeV). The composite which contains the maximum amount of Bi2O3 nanoparticles (40%Epoxy + 50% Red clay + 10% Bi2O3 NPs, coded as ERB-30) has lower TF than the other composites. The TF data demonstrated that ERB-30 is capable of producing more effective attenuation from gamma rays. We also determined the linear attenuation coefficient (LAC) for the prepared composites and we found that the LAC increases for a given energy in proportion to the Bi2O3 NPs ratio. For the ERB-0 (free Bi2O3 NPs), the LAC at 0.662 MeV is 0.143 cm−1, and it increases to 0.805 cm−1 when 10% of Bi2O3 NPs is added to the epoxy resin composite. The half value layer (HVL) results showed that the thickness necessary to shield that photons to its half intensity can be significantly lowered by increasing the weight fraction of the Bi2O3 NPs in the epoxy resin composite from 0 to 30%. The HVL for ERB-20 and ERB-30 were compared with other materials such as (Epoxy as a matrix material and Al2O3, Fe2O3, MgO and ZrO2 as filler oxides in the matrix at 0.662 MeV. The HVL values for ERB-20 and ERB-30 are 4.385 and 3.988 cm and this is lower than all the selected epoxy polymers. [ABSTRACT FROM AUTHOR]