Abstract
Glasses with composition of (60 - x) TeO2 - 10SrO - (30 + x) B2O3 were fabricated by melt quenching method. The structural features have been studied using X-ray diffraction (XRD) and FTIR. The derivative of absorption spectra fitting (DASF) method has been utilized to determine the optical band-gap energy. The measured band-gap energies takes values 3.521, 3.558, 3.581, 3.620 and 3.669 eV for the BSrTe60, BSrTe55, BSrTe50, BSrTe45 and BSrTe40, respectively. The band-gap energies increase with a decrease in the mol% of concentration of TeO2. The transitions involved are found to be indirect transitions. The MCNP-5 simulation code was put to use in estimating gamma photons' mean path length in the material. The lowest linear attenuation coefficient (mu) values lie within the range of 0.162 and 0.107 cm(-1) and are detected around 8 MeV. The LAC values decreased linearly with substituting the TeO2 by B2O3 content. The lowest half-value layer (HVL) is found at low energy (around 0.005 cm at 0.015 MeV). The mean free path (MFP) decreases linearly with increasing the TeO2 content and followed the trend: (MFP)(BSrTe60) < (MFP) (BSrTe55) < (MFP) (BSrTe50) < (MFP) (BSrTe45) < (MFP) (BSrTe40). The MFP of BSrTe60 and BSrTe55 at 0.662 MeV is 2.620 and 2.950 cm, and this is lower than the MFP of some commercial glasses such as RS 253 (MFP = 5.263 cm, RS 253-G18 (MFP = 5.263 cm), RS 323-G19 (MFP = 3.571 cm) and RS 360 (MFP = 3.125 cm) at the same energy.