This article contains detailed evaluation of thermal, mechanical, radiation shielding and thermoluminescence (TL) properties of heavy metal oxide (HMO) borosilicate glasses having composition xBi2O3- (60-x) B2O3- 20SiO2- 12ZnO- 8BaO (with x= 0, 2, 4, 6, 8, 10 and 12 mol%). Gamma shielding capacity of these glasses was examined in terms of mass attenuation coefficient (MAC) values, exposure and energy absorption build- up factor (EBF/EABF). The experimental MAC values were found to agree well with the theoretical results obtained from Photon Shielding and Dosimetry (PSD/Phy-X) software. Geometric Progression fitting method was used for the calculation of build- up factors in the photon energy region of 0.015-15 MeV with the help of five parameters (a, b, c, d and Xk). The pattern followed by build-up factors with the gamma energy and their variation for different penetration depths up to 40 mfp was observed and analysed. High values of equivalent atomic number and build up factors for high bismuth sample (12 mol%) gave evidence for its improved radiation shielding capacity. Furthermore, thermoluminescence study was done to assess the suitability of the synthesized glasses as a radiation dosimeter in the gamma dose range of 0.25 – 30 kGy. Here, 5 kGy irradiation exhibited major quenching in TL signal on adding bismuth to the glass network. TL performance of ZBiB-8 was noteworthy with charges trapped in high temperature trap centres with longer lifetime. TL dose response curve of ZBiB-8 showed good linearity in the dose range of 0.25 – 5 kGy. Fading analysis was done for this sample to find the loss in TL intensity in the course of one month. Heating the ZBiB-8 sample to 323 K (50 0C) for 15 min was found to be a proper annealing condition for re-using it as a thermoluminescence dosimeter (TLD).

ABSTRACT The purpose of this study is to develop a low cost, locally produced concrete mixture with optimum marble content. The resulting mixture would have enhanced strength properties compared to the non-marble reference concrete, and improved radiation shielding properties. To accomplish these goals ve concrete mixtures were prepared, containing 0, 5, 10, 15 and 20 % marble waste powder as a cement replacement on the basis of weight. These samples were subjected to a compressive strength test. The shielding parameters such as mass attenuation coecients (m), mean free path (MFP), efective atomic number (Zeff ) and exposure build-up factors (EBF) were measured, and results were compared with those obtained using the WinXcom program and MCNPX code in the photon energy range of 0.015 - 3 MeV. Moreover, the macroscopic fast neutron removal cross-section (neutron attenuation coeficient) was calculated and the results presented. The results show that the sample containing 10 % marble has the highest compressive strength and potentially good gamma ray and neutron radiation shielding properties.