Research Information System
RADIATION PHYSICS AND CHEMISTRY, vol.234, 2025 (SCI-Expanded)
Ordinary concrete (OC) is the most fundamental building material used in radiation areas, and it is known that increasing the thickness of concrete is effectively used for radiation protection. By adding different minerals or compounds into ordinary concrete, it is possible to transform it into a more effective radiation protection shield by increasing the density and thus linear attenuation coefficient of the new material. Besides the compound types and ratio which is filled in the ordinary concrete, the size of the material also important because of the effect on the surface to volume ratio During this study, linear attenuation coefficients were separately investigated using LAT and U cards with Lead Oxide (PbO) compounds of 50 nm (nm) and 100 nm sizes at a 20 % ratio reinforced in ordinary concrete by using the Monte Carlo Simulation MCNPX code. The simulation has been designed in a narrow beam geometry, and counts have been obtained using the F4 tally for 107 particles in photon mode only. The simulation results for monoenergetic gamma source energies which are commonly used in medical applications of ionizing radiation such as 511 keV (Na-22), 662 keV (Cs-137), 1173 keV, and 1332 keV (Co-60) show that reducing particle sizes increases the LAC (Linear Attenuation Coefficient). The highest effect is observed at 662 keV gamma energy with an improvement of 11 %. In addition, other important parameters for radiation protection such as MFP (Mean Free Path) and HVL (Half Value Layer) were calculated, and it was concluded that decreasing particle size enhances the radiation blocking properties.