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Lithium haloborate glasses in the form (70 – x) B2O3–30BaF2–xLiX where x = 0, 5, 10, 15 and 20 mol% and X = F, Cl and Br were prepared. The density, molar volume, IR spectra and elastic moduli of the obtained glasses were investigated. The glasses mainly composed from BO3, BO2F triangles and BO4, BOF3 tetrahedra structural units sharing corners. Increasing the amount of halogen ions leads to a decrease in the glass molar volume, and increases in the glass density, the average cross‐link density, the B–O bond length and the elastic moduli. The increase of elastic moduli is attributed to the increase in both the density and the average cross‐link density of the glasses. More elastic glasses can be obtained by introducing a larger halogen ion into the glass. An equation was derived to calculate Young's modulus for the glasses.

The main goal of this work is to find natural rock materials that can be used as effective gamma rays shielding at minimal cost, reliability and wide applications. It must be at particular weight and volume (lighter and more protection). Natural bentonite clay can be used as shelters from nuclear waste because of its large availability and low cost. Bentonite clay was used in two forms naturally as it is from its ores and in ground phase. Natural bentonite was cut into cylindrical pellets at different thicknesses; also, the other form pressed into cylindrical pellets with different thicknesses and different pressing pressures (50, 100 and 150 bar). The different samples are coated with polyvinyl alcohol polymer to prevent nuclear waste leakage through porosity of clay. Chemical analysis and density are measured for all samples. Bentonite clay was found naturally in nanometer scale because it is formed from volcanic ash deposits. The nanoparticle size was determined by dynamic light scattering and Williamson-Hall size analysis using XRD patterns and the help of X-powder program. The particle size of natural bentonite was found to be 59.79 nm. The microstructure was characterized by scanning electron microscope and transmission electron microscopy. The linear and mass attenuation coefficients of nano-structured bentonite clay (natural and pressed) were determined at 662 keV energy of 137 Cs; at 1173 and 1332 keV energies of 60 Co, gamma ray sources were determined by using NaI(Tl) scintillation detector. The experimental results showed that the ground bentonite pressed at 150 bar gave the highest linear and mass attenuation coefficients than other samples. The theoretical and the experimental calculations of mass attenuation coefficient were found to be in a good agreement.

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