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In this work, four waste paper composites were studied in terms of several photon interaction parameters over the energy region from 0.015 to 15.0 MeV. The waste paper and natural rubber (WP/NR) composites of different densities ranging from ρ = 0.894 to 1.16 gm⋅cm-3 were used for shielding radioactive rubble at different time period stages. Some additives were also used including high-abrasion furnace black, paraffin wax, B4C, as well as magnetite. The deduced parameters of photon interaction: equivalent atomic number Zeq, exposure buildup factor and energy absorption buildup factor have been studied as a function of incident photon energy, WP/NR elemental composition, and for penetration depths, up to 40 mean free path. The Zeq numbers have shown slight variation over the selected incident energy range and buildup factors were found to be modest at low and high photon energy meanwhile their values increase widely over the intermediate energy region. In addition, kerma relative to air for photon energies from 1 to 20 MeV were computed and show dependence upon equivalent atomic numbers. In this work, it was clear that filled samples offer better shielding capabilities than unfilled ones. The obtained data could be useful for radiation physicists and scientists in estimating the γ-irradiation received after applying such shields.

This work is dedicated to figuring out robust epoxy/magnetite/boron carbide (EP/Mag/B4C) composite for radiation attenuation at multiple applications related to nuclear installations, as well as restoration mortar for cracking developed in concrete biological shields. The mechanical properties (flexural, compressive, and impact strengths) and the physical properties (water absorption, porosity, and dry bulk density), each, have been performed to label the composite integrity for practical application. In practice, attenuation properties have been performed by using a collimated beam emitted from spontaneous fission 252Cf (100 μg) neutron source and neutron gamma spectrometer with stilbene scintillator. The pulse shape discrimination technique which would come of the zero cross over method was used to measure the fast neutron and gamma-ray spectra. Thermal neutron fluxes have been measured by using the thermal neutron detection system and the BF-3 detector. The attenuation parameters: precisely, macroscopic effective removal cross-sections ΣR (cm-1), macroscopic cross-sections Σ (cm-1), and total attenuation coefficients μ (cm-1) of fast and thermal neutrons and total gamma-rays respectively were evaluated using the attenuation relations. Also, the MCNP5 code and MERCSF-N program have been used to compute the parameters theoretically. When applicable, measured and calculated results were compared, and it tells us a comprehensive agreement.