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Photon interaction parameters of some chemical compounds in hard tissue were investigated in the energy range (1keV-100 GeV) by using the (NistXCom) program. These interaction parameters: mass attenuation coefficients (μρ), effective atomic number (Zeff), and electron density (Nel) as a measure of the absorption of photon energy by compounds in hard tissue. The events that cause absorption are the photoelectric effect, Compton effect, and pair formation events. Effective atomic numbers and electron densities of some compounds in hard tissue were calculated using the obtained mass attenuation coefficients. From the obtained data, the values of photon interaction parameters have been investigated to change with energy and compounds of the hard tissue. The variations of these parameters with energy are shown graphically for all photon interactions. Also, we calculated the half-value thickness (HVT) and μρ for some compounds Al2O3, SiO2 and MgO are agree with the theoretical value.

We investigated the radiation shielding competence for TeO2–V2O5–MoO3 glasses. The Phy-X software was used to report the radiation shielding parameters for the present glasses. With an increase in TeO2 and MoO3 content, the samples' linear attenuation coefficient improves. However, at low energies, this change is more apparent. At low energy, the present samples have an effective atomic number (Zeff) that is relatively high (in order of 16.17–24.48 at 0.347 MeV). In addition, the findings demonstrated that the density of the samples is a very critical factor in determining the half value layer (HVL). The minimal HVL for each sample can be found at 0.347 MeV and corresponds to 1.776, 1.519, 1.391, 1.210 and 1.167 cm for Te1 to Te5 respectively. However, the highest HVL of these glasses is recorded at 1.33 MeV, which corresponds to 3.773, 3.365, 3.218, 2.925 and 2.908 cm respectively. The tenth value layer results indicate that the thickness of the specimens needs to be increased in order to shield the photons that have a greater energy. Also, the TVL results demonstrated that the sample with the greatest TeO2 and MoO3 concentration has a higher capacity to attenuate photons.

Over the last few years, lead-free inorganic metal perovskites have gained impressive ground in empowering satellites in space exploration owing to their material stability and performance evolution under extreme space environments. The present work has examined the versatility of eight such perovskites as space radiation shielding materials by computing their photon, charged particles and neutron interaction parameters. Photon interaction parameters were calculated for a wide energy range using PAGEX software. The ranges of heavy charged particles (H, He, C, N, O, Ne, Mg, Si and Fe ions) in these perovskites were estimated using SRIM software in the energy range 1 keV–10 GeV, and that of electrons was computed using ESTAR NIST software in the energy range 0.01 MeV–1 GeV. Further, the macroscopic fast neutron removal cross-sections were also calculated to estimate the neutron shielding efficiencies. The examined shielding parameters of the perovskites varied depending on the radiation type and energy. Among the selected perovskites, Cs2TiI6 and Ba2AgIO6 displayed superior photon attenuation properties. A 3.5 cm thick Ba2AgIO6-based shield could reduce the incident radiation intensity to half its initial value, a thickness even lesser than that of Pb-glass. Besides, CsSnBr3 and La0.8Ca0.2Ni0.5Ti0.5O3 displayed the highest and lowest range values, respectively, for all heavy charged particles. Ba2AgIO6 showed electron stopping power (on par with Kovar) better than that of other examined materials. Interestingly, La0.8Ca0.2Ni0.5Ti0.5O3 demonstrated neutron removal cross-section values greater than that of standard neutron shielding materials - aluminium and polyethylene. On the whole, the present study not only demonstrates the employment prospects of eco-friendly perovskites for shielding space radiations but also suggests future prospects for research in this direction.

In this paper, the EPICS2017 photoatomic database was used to evaluate the photon mass attenuation coefficients and buildup factors of soils collected at different depths in the Philippine islands. The extraction and interpolation of the library was accomplished at the recommended linear-linear scales to obtain the incoherent and total cross section and mass attenuation coefficient. The buildup factors were evaluated using the G-P fitting method in ANSI/ANS-6.4.3. An agreement was achieved between XCOM, MCNP5, and EPICS2017 for the calculated mass attenuation coefficient values. The buildup factors were reported at several penetration depths within the standard energy grid. The highest values of both buildup factor classifications were found in the energy range between 100 and 400 keV where incoherent scattering interaction probabilities are predominant, and least at the region of predominant photoionization events. The buildup factors were examined as a function of different soil silica contents. The soil samples with larger silica concentrations were found to have higher buildup factor values and hence lower shielding characteristics, while conversely, those with the least silica contents have increased shielding characteristics brought by the increased proportions of the abundant heavier oxides.

An attempt has been made to experimentally investigate the optimum thickness in order to measure mass attenuation coefficients for some Sn–Pb alloy systems at incident photon energies 122, 511 and 662keV. The Sn–Pb alloys were synthesized with different compositions and different thicknesses using melt-quench technique and cast iron mould. The physical parameters such as mass, thickness, density have been measured for all the prepared alloys. Further, the transmitted photon spectra of Cs-137, Co-57 and Na-22 radioactive isotopes were recorded using GAMMARAD5 (scintillator detector) of dimensions 76mm×76mm with and without inserting different alloy samples between the radioactive isotopes and detector. The experimental results so obtained were compared with the theoretical ones of WinXCom and optimum thickness for measuring mass attenuation coefficients for the selected alloys has been recommended.

This study aims to determine the effect of fly ash with a high replacing ratio of clay on the radiation shielding properties of bricks. Some interaction parameters (mass attenuation coefficients, half value layer, effective atomic number, effective electron density, and absorption efficiency) of clay fly ash bricks were measured with a NaI(Tl) detector at 661.6 keV, 1,173.2 keV, and 1,332.5 keV. For the investigation of their shielding behavior, fly ash bricks were molded using an admixture to clay. A narrow beam transmission geometry condition was used for the measurements. The measured values of these parameters were found in good agreement with the theoretical calculations. The elemental compositions of the clay fly ash bricks were analyzed by using an energy dispersive X-ray fluorescence spectrometer. At selected energies the values of the effective atomic numbers and effective electron densities showed a very modest variation with the composition of the fly ash. This seems to be due to the similarity of their elemental compositions. The obtained results were also compared with concrete, in order to study the effect of fly ash content on the radiation shielding properties of clay fly ash bricks. The clay fly ash bricks showed good shielding properties for moderate energy gamma rays. Therefore, these bricks are feasible and eco-friendly compared with traditional clay bricks used for construction.

Gamma ray shielding properties of borate glass samples containing oxides of lead and zinc are prepared by melt and quench technique and evaluated theoretically using XCOM computer software for gamma ray shielding properties. However, gamma ray shielding properties are discussed in terms of various calculated parameters such as half value layer, mean free path and mass attenuation coefficient. The calculated parameters are compared by the author with conventional shielding material concrete. FTIR studies are undertaken to investigate the various structural groups present in the prepared system. Furthermore, it was observed that the glass sample S1 posses minimum HVL value and maximum mass attenuation coefficient, It has been inferred that addition of lead improve the gamma ray shielding properties and simultaneously decrease the rigidity of the glass systems due to formation of non bridging oxygen. Gamma ray shielding properties of our glass systems have been compared with standard nuclear radiation shielding concrete.