This study aimed to perform an investigation for the potential implementation of bismuth silicate glasses as novel shield equipment instead of ordinary shields in nuclear medicine facilities. Accordingly, a group of Bi2O3 reinforced silicate glass system were investigated and compared with ordinary shields in terms of their gamma-ray attenuation properties in diagnostic nuclear medicine radioisotope energies emitted from 99mTc, 111In, 67Ga, 123I, 131I, 81mKr, 201Tl, 133Xe. Mass attenuation coefficient (μm) results for glass samples were calculated comparatively with the XCOM program and MCNPX code. The gamma-ray attenuation parameters such as half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff) were obtained in the diagnostic gamma ray energy range from 75 to 336 keV. To confirm the attenuation performance of superior sample, obtained results were extensively compared with ordinary shielding materials. According to the results obtained, BISI6 glass sample with the highest Bi2O3 additive has an excellent gamma-ray protection.

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IntroductionWe report the breast and chest radiation dose assessment for mammographic examinations using a three-layer heterogeneous breast phantom through the MCNPX Monte Carlo code.MethodsA three-layer heterogeneous phantom along with compression plates and X-ray source are modeled. The validation of the simulation code is obtained using the data of AAPM TG-195 report. Deposited energy amount as a function of increasing source energy is calculated over a wide energy range. The behavioral changes in X-ray absorption as well as transmission are examined using the F6 Tally Mesh extension of MCNPX code. Moreover, deposited energy amount is calculated for modeled body phantom in the same energy range.Results and discussionsThe diverse distribution of glands has a significant impact on the quantity of energy received by the various breast layers. In layers with a low glandular ratio, low-energy primary X-ray penetrability is highest. In response to an increase in energy, the absorption in layers with a low glandular ratio decreased. This results in the X-rays releasing their energy in the bottom layers. Additionally, the increase in energy increases the quantity of energy absorbed by the tissues around the breast.

Background: During mammography, a lead-acrylic protective screen is recommended to reduce radiation exposure to the unexposed breast. Objectives: This research study aimed to construct an Indium-(III)-oxide-rich tellurite-glass screen (TZI8) and compare its performance to that of lead acrylic. Materials and Methods: A three-layer heterogeneous-breast phantom was developed, using the MCNPX (version 2.7.0) Monte Carlo code. An MCNPX-simulation geometry was designed and implemented, using the lead-acrylic and TZI8 shielding screens between the right and left breast. Next, the reliability of the phantom and the variations in absorption between the lead-acrylic and TZI8 glass were investigated. Results: The findings show that the TZI8-protective-glass screen offers significantly greater radioprotection than the lead-acrylic material. The quantity of total dose absorbed in the unexposed breast was much lower for TZI8 than for lead-based acrylic. The TZI8-glass screen gives about 60% more radioprotection than the lead-acrylic screen. Conclusion: Considering the toxic lead in the structure that may be hazardous to the human tissues, the TZI8-glass screen may be used in mammography examination to provide greater radioprotection than the lead-acrylic screen, in order to greatly reduce the dose to the unexposed breast.

We report the mechanical properties, elastic moduli, and gamma ray attenuation properties of some TeO2–WO3–GdF3 glasses. Using the chemical composition of the selected glasses, the dissociation energy per unit volume (G t ) and the packing density (V t ) were calculated. Using the G t and V t values, Young’s, Shear, Bulk, Longitudinal Modulus, and Poisson’s ratio of the glasses are calculated. Next several fundamental gamma ray attenuation properties such as linear and mass attenuation coefficients, half value layer, mean free path, effective atomic number, effective electron density, effective conductivity, exposure, and energy absorption buildup factors are calculated in 0.015–15 MeV energy range. As a consequence of WO3–GdF3 substitution, the glass densities are observed in different values. The overall gamma ray attenuation properties are found to be enhanced through WO3 addition. Moreover, the increasing WO3 incorporation into glass configuration decreases the overall elastic moduli of glasses. It can be concluded that increasing WO3 may be a useful tool for enhancing the gamma ray attenuation qualities and decreasing the elastic moduli of TeO2–WO3–GdF3 in situations where a material with versatile mechanical properties is required.