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Based on the experimental and theoretical radiation attenuation, this study produced and tested a composite material made of polyester reinforced with SnO at varied concentrations and abbreviated as Pol-SnOx, where x = 0–60% with steps of 20 wt% Also, the polyester samples were doped with SnO of different particle sizes: Micro, Nano, and 50% Micro/50% Nano mix to investigate the effect of the particle size on the radiation attenuation performance. In the photon energy range of 0.015–15 MeV, their radiation shielding properties were empirically determined using an HPGe detector and theoretically determined using Phy-X/PSD software. The linear attenuation coefficient (LAC) values dropped from 1.361 to 0.022 cm−1 for Pol-SnO0, from 13.611 to 0.033 cm−1 for Pol-SnO20, from 31.700 to 0.049 cm−1 for Pol-SnO40, and from 61.076 to 0.076 cm−1 for Pol-SnO60 in the photon energy (Eγ) range from 0.015 to 15 MeV. The LAC values of the fabricated Pol-SnOx samples increased as the SnO concentrations increased. Also, the addition of 50% Micro/50% Nano mix particle size of the SnO to the polyester significantly increased the values of the LAC. The percentages of LAC improvement of SnO nano-particles were 16.625%, 13.236%, 8.714%, and 7.935% at the Eγ values of 0.059, 0.661, 1.173, and 1.332 MeV, respectively. Also, the LAC values were enhanced by adding SnO containing 50% Micro/50% Nano mix particles by 19.097%, 15.271%, 9.854%, and 9.071% at the Eγ values of 0.059, 0.661, 1.173, and 1.332 MeV, respectively, when compared to microparticles. The addition of 50% Micro/50% Nano Mix of SnO with 60% content to the polyester showed the highest LAC and radiation protection efficiency and lowest half-value layer and transmission factor among the other samples due to increased SnO doping and interparticle distances of the Micro and Nano mix.

Radiation and nuclear technologies have side effects in addition to their important applications, so appropriate shields must be used to protect users and the public from high doses as a result of exposure to this radiation. In this work, the attenuation coefficients for polyester composites doped with waste iron filings (IFs) were studied. Six samples of different IF concentrations were manufactured, namely, Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60 (where Poly-IF60 represents 40% polyester and 60% IF). We measured the attenuation factors using high purity germanium (HPGe)-detector along with three radioactive sources 241Am (emitting energy of 0.06 MeV), 137Cs (emitting energy of 0.662 MeV), and Co-60 (emitting energy of 1.173 and 1.333 MeV). We compared the linear attenuation coefficient (LAC) obtained by theoretical (i.e., XCOM software) and experimental (i.e., HPGe-detector) approaches for the prepared polyester composites at various photon energies (0.060, 0.662, 1.173, and 1.333 MeV). The greatest difference between the LAC values of the samples occurs at 0.060 MeV, where the Poly-IF60 sample has a much greater LAC than the other shields, followed by the Poly-IF50 sample, Poly-IF40 sample, and so on until the pure polyester shield. Specifically, their values are equal to 0.245, 0.622, 0.873, 1.187, 1.591, and 2.129 cm−1 for Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60, respectively. We calculated the transmission factor (TF) and the radiation shielding efficiency (RSE), and found that the TF for Poly-IF30 is equal to 28.82%, 77.94%, 82.75%, and 83.75% at 0.060, 0.662, 1.173, and 1.333, respectively, while its RSE is equal to 82.57%, 24.00%, 18.80%, and 17.72%, respectively. The fast neutron removal cross-section (FNRC) of the polyester samples was calculated and the values increase when more Ifs are added to the samples. More specifically, the FNRC values are equal to 0.095, 0.100, 0.103, 0.107, 0.110, and 0.113 cm−1 for Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60, respectively.

In this work, we studied the effect of bismuth oxide particle size and its attenuation capacity as a filler additive in epoxy resins. Six samples were prepared according to the amount of microparticles and nanoparticles in the sample and were coded as ERB-1, ERB-2, ERB-3, ERB-4, ERB-5, and ERB-6. One of the composite epoxies contained Bi2O3 microparticles at a 50:50 ratio (ERB-6) and was chosen as the control composite, and the number of microparticles (MPs) was gradually decreased and replaced by nanoparticles (NPs) to produce epoxy-containing Bi2O3 nanoparticles at a 50:50 ratio (ERB-1). The morphological and thermal characteristics of the studied composites were tested. The attenuation capability of the prepared composites, which is determined by the Bi2O3 particle size, was determined experimentally using a semiconductor detector, an HPGe-detector, and three different gamma-ray point sources (Am-241, Co-60, and Cs-137). The linear attenuation coefficient (LAC) of ERB-3, which contained 30% nanoparticles and 20% microparticles, had the highest value compared to the other composites at all the energies discussed, while the ERB-6 composite had the lowest value at all energies. The radiation-shielding efficiency (RSE) of the prepared samples was determined at all discussed energies; at 662 keV, the radiation-shielding efficiency values were 15.97%, 13.94%, and 12.55% for ERB-3, ERB-1, and ERB-6, respectively. The statistics also proved that the attenuation capacities of the samples containing a combination of nanoparticles and microparticles were much superior to those of the samples containing only microparticles or nanoparticles. A ranking of the samples based on their attenuation capacity is as follows: ERB-3 > ERB-4 > ERB-2 > ERB-1 > ERB-5 > ERB-6. [ABSTRACT FROM AUTHOR]

The investigation in this article focused on the role of La2O3 on the optical, physical, and radiation protection performance of La2O3-based glasses in the form 21.5SiO2-58.5B2O3-(20−x)ZnO:xLa2O3, where x , ( 0 ≤ x ≤ 10 ) mol%. The melt-quenching process was used to synthesize the glasses under study. Density results increased from 3.174 to 4.754, the values of the ( E opt. indi ) increased from 2.996 to 3.313 and ( E opt. di) increased from 3.364 to 3.689. Several radiation shielding factors have been evaluated to study the attenuation abilities of the ZBSL glasses and for all of them, there is a positive correlation between the mean free path (MFP) values and the incoming photon energy. The effective atomic number, Zeff, values increased for all the energies when La2O3 was employed in place of ZnO. Therefore, of all the competing shielding glasses and regular concrete, ZBSL10 glass is an excellent choice for shielding applications from gamma rays and neutrons. This study should be very beneficial for the design of these glasses or for the fabrication of new glasses for radiation protection. [ABSTRACT FROM AUTHOR]

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]

Due to distinct photoelectric absorption properties and physiochemical features, high-atomicelement nanomaterials are frequently used as radiosensitizer for radiotherapy, such as gold nanoparticles. which in-turn can increase radiation dose to tumours while minimizing exposure to normal tissues. The aim of this study is to investigate the dose enhancement due to the presence of nanogold particles mixed with breast tissue using a real radiotherapy plan with two photon energies, with and without flattening filter. A fully validated linac head was used to model a complete field-in-field (FIF) radiotherapy breast plan using 4 and 6 MV with a flattening filter (FF) and flattening filter-free (FFF) using BEAMnrc/EGSnrc MC code. The dose distributions were simulated in a female ICRP voxel computational phantom. The dose enhancement ratio (DER) and flattening filter-free enhancement ratio (FFFER) were calculated for a range of nanogold concentrations. The results showed that the DER increased with increasing nanogold concentration. The maximum DER was achieved when FFF was used and the increase was higher for 4 MV than 6 MV. The FFFER was higher for the 4 MV beam than 6 MV when 40 mg/ml nanogold was used. The combination of higher nanogold concentrations, lower photon energies, and FFF resulted in a higher dose enhancement. The implementation of nanogold particles in breast tissue enhanced the dose deposition, especially with FFF, as presented in this study. The results would improve nanogold-enhanced breast radiotherapy and dose delivery with an increase in patient throughput. [ABSTRACT FROM AUTHOR]

Using a male ICRP voxel computational phantom, Monte Carlo simulations were performed to estimate the dose enhancement ratio (DER) in prostate radiation for 6 and 10 MV photon energy. A fully validated linear accelerator head was used, initially with a single beam to calculate the DER for different concentrations of nanogold mixed with prostate tissue. Each energy was tested with (FF) and without (FFF) a flattening filter. The DER was then calculated for a verified 10 MV treatment plan to mimic the real treatment scenario. The results showed that the DER increased with concentration, especially for FFF mode. In addition, the flattening filter-free enhancement ratio (FFFER) was investigated, from which it was found that a 6 MV FFF with a 40 mg/ml concentration enhanced the dose by a factor of 1.03 compared to 6 MV FF. For the entire plan, the difference between FFF and FF for both energies was approximately 2%. [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]