Detailed Inspection of γ-ray, Fast and Thermal Neutrons Shielding Competence of Calcium Oxide or Strontium Oxide Comprising Bismuth Borate Glasses

For both the B2O3-Bi2O3-CaO and B2O3-Bi2O3-SrO glass systems, γ-ray and neutron attenuation qualities were evaluated. Utilizing the Phy-X/PSD program, within the 0.015–15 MeV energy range, linear attenuation coefficients (µ) and mass attenuation coefficients (μ/ρ) were calculated, and the attained μ/ρ quantities match well with respective simulation results computed by MCNPX, Geant4, and Penelope codes. Instead of B2O3/CaO or B2O3/SrO, the Bi2O3 addition causes improved γ-ray shielding competence, i.e., rise in effective atomic number (Zeff) and a fall in half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP). Exposure buildup factors (EBFs) and energy absorption buildup factors (EABFs) were derived using a geometric progression (G–P) fitting approach at 1–40 mfp penetration depths (PDs), within the 0.015–15 MeV range. Computed radiation protection efficiency (RPE) values confirm their excellent capacity for lower energy photons shielding. Comparably greater density (7.59 g/cm3), larger μ, μ/ρ, Zeff, equivalent atomic number (Zeq), and RPE, with the lowest HVL, TVL, MFP, EBFs, and EABFs derived for 30B2O3-60Bi2O3-10SrO (mol%) glass suggest it as an excellent γ-ray attenuator. Additionally, 30B2O3-60Bi2O3-10SrO (mol%) glass holds a commensurably bigger macroscopic removal cross-section for fast neutrons (ΣR) (=0.1199 cm−1), obtained by applying Phy-X/PSD for fast neutrons shielding, owing to the presence of larger wt% of ‘Bi’ (80.6813 wt%) and moderate ‘B’ (2.0869 wt%) elements in it. 70B2O3-5Bi2O3-25CaO (mol%) sample (B: 17.5887 wt%, Bi: 24.2855 wt%, Ca: 11.6436 wt%, and O: 46.4821 wt%) shows high potentiality for thermal or slow neutrons and intermediate energy neutrons capture or absorption due to comprised high wt% of ‘B’ element in it.


Introduction
Nowadays, utilization and generation of radiation are eminent in distinct technological applications, such as nuclear fission reactors for clean energy (e.g., 235 U or 239 Pu fissile isotopes' usage), therapeutic nuclear medicine (radiopharmaceuticals, e.g., 137 Cs, 60 Co, 99m Tc, and 123 I radioisotopes handling for disease (oncology) diagnosis and treatment, singlephoton emission computed tomography (SPECT)-body tissues and organs imaging), and outer space research. In these fields, to assure safety and protection of radiation workers, nuclear medicine staff members, and astronauts from deleterious effects of undesired radiation (e.g., γ-rays, neutrons, β-particles, in space-high energy electrons, protons, and heavy ions, etc.) exposure, appropriate shielding materials are compulsory. For instance, as a fission product of 235 U, 137 Cs radioactive isotope, which emits high energy β-particles and γ-rays (charge = 0, rest mass = 0), highly contaminates the surrounding environment (water, soil, air) once any nuclear reactor accident occurs (e.g., Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, Japan, 2011) [1]. In humans, external exposure to 137 Cs (in greater amounts) can cause radiation burns, acute radiation sickness (ARS), coma, and even death, while internal exposure through inhalation/ingestion increases cancer (abnormal growth in cells) risk. Likewise, neutrons (originated as a product of nuclear fission and radioactive decay, mass and charge = 939.57 MeV and 0) can travel larger distances in air, and, owing to their remarkable ability to penetrate other materials unlike α-particles, they are harmful to humans' soft tissues in organs when interacting with the body (which consists mostly of water). They directly interact with the atomic nuclei of living cells, causing ionization among nearby atoms. Generally, within the nucleus, neutron interaction greatly relies on incident energy and nucleus movement. The International Atomic Energy Agency (IAEA) [2] and International Commission on Radiological Protection (ICRP) [3] are the principal organizations that promote radiation safety and safeguard and set standards concerning radiation exposure limits for working personnel and the general public, apart from International Radiation Protection Association (IRPA) defined ALARA (As Low as Reasonably Achievable) principle. It is essential to limit radiation exposure by following the nuclear regulatory instructions at nuclear energy facilities and radiotherapy centers.
Customarily, concrete, owing to its favorable chemical composition (holds both light and heavy nuclei), low fabrication cost, ease of construction, and superior γ-rays and neutron attenuation ability, has been used for nuclear radiation shielding objectives. Nevertheless, concrete is known for some demerits, such as loss of moisture and consequent cracking due to radiation heat, poor mechanical features upon exposure to high energy γ-rays multiple scattering over time, elastic modulus and compressive and tensile strength degradation by neutron irradiation, bigger space occupation, opacity, and immovability [4,5]. An alternative to concrete, lead (Pb) and Pb-containing materials (manufactured in various shapes-slabs, plates, and sheets, etc.) possess excellent X-ray and γ-ray attenuation capacity, but 'Pb' has disadvantages, such as low melting point (600.6 K), and is detrimental to human health and the surrounding environment [6,7]. For these reasons, in recent times, different research groups have actively focused their efforts on finding suitable replacement materials for concrete and 'Pb', e.g., glasses, which demonstrate encouraging characteristics, such as low cost, medium to high density (ρ), structural stability with prolonged irradiation, high mechanical and thermal strength, better optical (visible light) transparency, nontoxicity (100% recyclable), and environmental safety [8][9][10][11][12][13][14][15]. B 2 O 3 (B (Z = 5)) glasses possess low manufacturing cost compared to TeO 2 and GeO 2 glasses, lower melting points than SiO 2 glasses, adequate optical transparency, good thermal stability, and ample glass formation tendency when B 2 O 3 has high dissociation energy (=356 kcal/mol) and large single B-O bond strengths-498 kJ/mol ('B' CN (coordination number) = 3) and 373 kJ/mol ('B' CN = 4), accordingly [16]. Pure B 2 O 3 glass (holds planer BO 3 and B 3 O 3 boroxol ring structural units ('B' CN = 3) [17]) has large phonon energy (~1300-1500 cm −1 ) and high hygroscopicity. Bi 2 O 3 (Bi (Z = 83)), Bi 3+ cation-low field strength and huge polarizability), a heavy metal oxide, plays a network forming or modifying role when included in the glass composition (e.g., B 2 O 3 ), forming [BiO 3 ] pyramidal units or [BiO 6 ] octahedral units in glass structure, contingent upon its high or low content [18]. Moreover, glasses with high Bi 2 O 3 (ρ = 8.9 g/cm 3 ) content exhibit high 'ρ', high refractive index (>2), and large third-order nonlinear optical susceptibility (χ (3) , about 10 −11 esu), apart from good chemical, thermal, and mechanical stabilities [19]. In addition, when added, alkaline earth oxides, such as CaO and SrO modify (breaks the B-O bonds) the B 2 O 3 glass network structure, converting 'B' CN from 3→4 by forming nonbridging oxygens, and also enhance the glass-forming regions [20,21].
With a motivation to propose cost-effective glasses as radiation shields as the primary aim of this current work, we studied µ, µ/ρ, Z eff , N eff , HVL, TVL, MFP, RPE, Z eq , EBF, and EABF using Phy-X/PSD for both B 2 O 3 -Bi 2 O 3 -CaO and B 2 O 3 -Bi 2 O 3 -SrO glass systems. EBFs and EABFs are deduced up to 40 mfp PDs. Further, Σ R and σ T values are also derived using Phy-X/PSD software and Geant4 code, including σ cs , σ ics , σ A , and σ T for thermal neutrons by a suitable formula.

γ-ray Shielding Features
All discussed results in this sub-section are for the 0.015-15 MeV photon energy range. For all S1-S6 samples, Figure 2 shows the variations of 'µ', calculated utilizing Phy-X/PSD, whereas for all C1-C6 samples obtained 'µ' variations are depicted in Figure S1 of the Supplementary Material. Following Figure 2 and Figure S1, one can find that with photon energy increment, 'µ' has an identical γ-rays reliance, and it increases considerably with the increasing Bi 2 O 3 content, i.e., larger wt% of high Z (Bi (Z = 83)) element in place of proportionately lower Z constituents, B (Z = 5)/Ca (Z = 20)/Sr (Z = 38) in samples C1 to C6 and S1 to S6. Among all C1-C6 and S1-S6 samples, glass S6 has, relatively, the highest 'µ' due to the largest wt% of Bi (=80.6813 wt%, see

γ-Ray Shielding Features
All discussed results in this sub-section are for the 0.015-15 MeV photon energy range. For all S1-S6 samples, Figure 2 shows the variations of 'µ', calculated utilizing Phy-X/PSD, whereas for all C1-C6 samples obtained 'µ' variations are depicted in Figure S1 of the Supplementary Material. Following Figure 2 and Figure S1, one can find that with photon energy increment, 'µ' has an identical γ-rays reliance, and it increases considerably with the increasing Bi2O3 content, i.e., larger wt% of high Z (Bi (Z = 83)) element in place of proportionately lower Z constituents, B (Z = 5)/Ca (Z = 20)/Sr (Z = 38) in samples C1 to C6 and S1 to S6. Among all C1-C6 and S1-S6 samples, glass S6 has, relatively, the highest 'µ' due to the largest wt% of Bi (=80.6813 wt%, see Table 2) in it. Except for S1 glass, the remaining all samples possess maximal 'µ' at 15 KeV energy while sample S1 holds maximum 'µ' (=128.586 cm −1 ) at 20 KeV energy owing to Bi: L1absorption edge (L1-absorption edge-Bi: 16 [55], for all chosen samples, a sharp decrement in 'µ' is observed. As an example, for C6 and S6 glasses, at 0.04 and 0.4 MeV energies, the derived 'µ' quantities are 82.55021 and 1.454471 cm −1 and 93.97439 and 1.604014 cm −1 , respectively. For all C1-C6 and S1-S6 glasses, at 0.1 MeV, a quick rise in 'µ' transpired because of Bi: K-absorption edge at 90.5259 KeV (see Figure S1 and Figure 2). Then, for C1 and S1 glasses from 0.5 to 10 MeV, C2 sample from 0.5 to 8 MeV, C3 glass from 0.5 to 6 MeV, C4, C5, and C6 samples from 0.5 to 5 MeV, S2 and S3 samples from 0.5 to 6 MeV, S4 and S5 glasses from 0.5 to 5 MeV, and S6 glass from 0.5 to 4 MeV energies, changes or reductions in 'µ' are very small as the Compton scattering (CS) (∝ E −1 ) mechanism [55] controls these intermediate energy ranges. Next, in the higher energy regions, i.e., for C1 and S1 samples, above 10 MeV; for C2 glass, after 8 MeV; for C3 sample, beyond 6 MeV; for C4, C5, and C6 glasses, after 5 MeV; for S2 and S3 glasses, above 6 MeV; for S4 and S5 samples, after 5 MeV; and for S6 sample, beyond 4 MeV up to 15 MeV, a slight hike in 'µ' owing to pair production (PP) (∝ log E) [55] phenomenon command is identified. For instance, at 4, 5, and 15 MeV energies, for S6 glass, the calculated 'µ' values are 0.3052, 0.3057, and 0.3809 cm −1 , accordingly. By emitting minimal penetrating capability charged particles, commonly, in both PEA and PP actions, photons can be fully absorbed by the substances whereas the CS process results in photons energy partial degradation only and allows them to possess significant leftover energy for larger penetration depths to reach that lead to bigger fleeing probabilities. From the achieved 'µ' results, one can see that for the lowest energy photons absorption or reduction, all selected C1-C6 and S1-S6 samples are good.
In Figures S3-S7 of the Supplementary Material, we presented all the changes of Z eff , N eff , HVL, TVL, and MFP values within inspected γ-rays energy range for all C1-C6 and S1-S6 glasses with relevant discussion. Figure 3 demonstrates the sample S6 MFP comparison with relevant commercial shielding glasses' [56] values, and likewise glass S6 HVL comparison with these commercial glasses is shown in Figure S8 of the Supplementary Material. Here, at all three corresponding 0.2 MeV, 0.662 MeV ( 137 Cs), and 1.25 MeV ( 60 Co) γ-ray energies, sample S6 has less HVL and MFP than the commercial glasses (see Figure S8 and Figure 3). So sample S6 has superior γ-ray shielding capacity than the compared commercial glasses owing to its larger 'µ' than them. Earlier, SS403, CN, CS516, IL600, and MN400 alloys [57],  [58], and concretes, such as OC, BMC, HSC, IC, ILC, SMC, and SSC [59] were also reported for nuclear radiation shielding purpose by other researchers. S1-S6 glasses with relevant discussion. Figure 3 demonstrates the sample S6 MFP comparison with relevant commercial shielding glasses' [56] values, and likewise glass S6 HVL comparison with these commercial glasses is shown in Figure S8 of the Supplementary Material. Here, at all three corresponding 0.2 MeV, 0.662 MeV ( 137 Cs), and 1.25 MeV ( 60 Co) γ-ray energies, sample S6 has less HVL and MFP than the commercial glasses (see Figure S8 and Figure 3). So sample S6 has superior γ-ray shielding capacity than the compared commercial glasses owing to its′ larger 'µ' than them. Earlier, SS403, CN, CS516, IL600, and MN400 alloys [57], C5H8, C3H3N, C5H8O2, C10H8O4, CH2O, and C10H10O2 polymers [58], and concretes, such as OC, BMC, HSC, IC, ILC, SMC, and SSC [59] were also reported for nuclear radiation shielding purpose by other researchers. For high Z elements (e.g., Bi) containing compounds, generally, at <0.5 MeV photon energies, the PEA (all photon energy fully passing on to a bound electron) is so common, and the CS phenomenon prevails at relatively moderate and greater γ-ray energies (~500 KeV-1.5 MeV). Further, to undergo the PP process, incident photons must possess energies >1.022 MeV, specifically in larger Z substances, and subsequently for the two 511 keV γ-rays (owing to positron + electron annihilation) generations that go separately in opposed directions. Here, with improving Z, the atomic cross-section for a certain PEA, CS, and PP phenomena enhances. Figures 4a,b and 5a,b show, for C1 and S1 glasses, at 1-40 mfp PDs the computed EBFs and EABFs variations appropriately. For all the remaining C2-C6 and S2-S6 samples, the respective EBFs and EABFs variations at 1-40 mfp PDs are presented in Figures  S9a-j and S10a-j in the Supplementary Material. The computed Zeq and related G-P fitting parameters for EBFs and EABFs derivations for all C1-C6 and S1-S6 samples are tabulated For high Z elements (e.g., Bi) containing compounds, generally, at <0.5 MeV photon energies, the PEA (all photon energy fully passing on to a bound electron) is so common, and the CS phenomenon prevails at relatively moderate and greater γ-ray energies (~500 KeV-1.5 MeV). Further, to undergo the PP process, incident photons must possess energies >1.022 MeV, specifically in larger Z substances, and subsequently for the two 511 keV γ-rays (owing to positron + electron annihilation) generations that go separately in opposed directions. Here, with improving Z, the atomic cross-section for a certain PEA, CS, and PP phenomena enhances. Figure 4a,b and Figure 5a,b show, for C1 and S1 glasses, at 1-40 mfp PDs the computed EBFs and EABFs variations appropriately. For all the remaining C2-C6 and S2-S6 samples, the respective EBFs and EABFs variations at 1-40 mfp PDs are presented in Figures S9a-j and S10a-j in the Supplementary Material. The computed Z eq and related G-P fitting parameters for EBFs and EABFs derivations for all C1-C6 and S1-S6 samples are tabulated in Tables S3-S14 of the Supplementary Material, accordingly. All studied glasses EBFs and EABFs exhibit an alike course with photon energy along with a sharp increase in these values at respective 0.02, 0.03, 0.06, 0.08, and 0.1 MeV energies owing to 'Bi' L1 and K-absorption edges. At lower γ-ray energies, i.e., from 15 KeV up to 150 KeV, EBFs and EABFs hold minimal quantities with negligible deviations, except the mentioned rises. As stated earlier, the PEA process commands this lower energy region. Beyond 0.015 MeV up to 1-2 MeV energy (up to 0.06/0.08 MeV at 1 mfp/2 mfp lower penetration depths) for C1 and S1 glasses, corresponding EBFs and EABFs are progressively improved, while for C2-C6 and S2--S6 samples these quantities are enhanced up to 2-3 MeV at higher 'mfp' due to CS mechanism (multiple scattered photons) supremacy over this moderate energy range. Usually, EBFs and EABFs move to larger energies for greater Z eq compounds. Then, with increasing γ-ray energy up to 15 MeV both C1 and S1 glasses show a complete decreasing trend in according EBFs and EABFs from 1 to 15 mfp, and at larger mfp, these values slowly increase at higher energies. For the remaining samples also, at smaller penetration depths, EBFs and EABFs changes are smaller up to 15 MeV energy, while they considerably enhance at greater mfp with energy rise up to 15 MeV. Usually the 'buildup' of photons appears at the bigger mfp, specifically for higher thickness substances and diversity of the incoming X-rays or γ-rays. Thus, relying on glass chemical composition (C1 to C6 and S1 to S6 glasses), for the obtained EBFs and EABFs alterations at bigger photon energies, the PP process dominates. Generally at higher energies and greater penetration depths, secondary photons scatterings happen frequently, leading to larger buildups. Overall, absorption activities lower the EBFs and EBFs whereas scattering phenomena improve them. Because of comparatively greater Z eq /Z eff , in all selected C1-C6 and S1-S6 glasses, sample S6 possesses the lesser EBFs and EABFs, indicating it as a more potent photon attenuator. and EABFs exhibit an alike course with photon energy along with a sharp increase in these values at respective 0.02, 0.03, 0.06, 0.08, and 0.1 MeV energies owing to 'Bi' L1 and Kabsorption edges. At lower γ-ray energies, i.e., from 15 KeV up to 150 KeV, EBFs and EABFs hold minimal quantities with negligible deviations, except the mentioned rises. As stated earlier, the PEA process commands this lower energy region. Beyond 0.015 MeV up to 1-2 MeV energy (up to 0.06/0.08 MeV at 1 mfp/2 mfp lower penetration depths) for C1 and S1 glasses, corresponding EBFs and EABFs are progressively improved, while for C2-C6 and S2--S6 samples these quantities are enhanced up to 2-3 MeV at higher 'mfp' due to CS mechanism (multiple scattered photons) supremacy over this moderate energy range. Usually, EBFs and EABFs move to larger energies for greater Zeq compounds. Then, with increasing γ-ray energy up to 15 MeV both C1 and S1 glasses show a complete decreasing trend in according EBFs and EABFs from 1 to 15 mfp, and at larger mfp, these values slowly increase at higher energies. For the remaining samples also, at smaller penetration depths, EBFs and EABFs changes are smaller up to 15 MeV energy, while they considerably enhance at greater mfp with energy rise up to 15 MeV. Usually the 'buildup' of photons appears at the bigger mfp, specifically for higher thickness substances and diversity of the incoming X-rays or γ-rays. Thus, relying on glass chemical composition (C1 to C6 and S1 to S6 glasses), for the obtained EBFs and EABFs alterations at bigger photon energies, the PP process dominates. Generally at higher energies and greater penetration depths, secondary photons scatterings happen frequently, leading to larger buildups. Overall, absorption activities lower the EBFs and EBFs whereas scattering phenomena improve them. Because of comparatively greater Zeq/Zeff, in all selected C1-C6 and S1-S6 glasses, sample S6 possesses the lesser EBFs and EABFs, indicating it as a more potent photon attenuator.    For all C1-C6 and S1-S6 samples (thickness, t = 1 cm), Figure S11 in the Supplementary Material and Figure 6 portrays variations of evaluated RPE quantities, separately. From samples C1 to C6 and S1 to S6 with improving Bi2O3 content from 5 to 50 mol% and 5 to 60 mol% respectively, RPE quantities are increased owing to Bi (Z = 83), a heavy element, which boosts the glass capacity in reducing incoming photons' intensity. Here among all studied samples, glass S6 (contains 60 mol% Bi2O3) has the relatively largest RPE at all energies. From 15 KeV up to 0.06 MeV energy, RPE has the biggest values for all glasses, indicating all samples' exceptional competence in obstructing the low energy γ-rays. As an example, the computed RPE values for C1, C2, C3, C4, C5, and C6 glasses at 15 and 60 KeV energies are 100% (for all samples) and 98.94%, 99.98%, 100%, 100%, 100%, and 100% accordingly, and these quantities at the same energies for S1, S2, S3, S4, S5, and S6 samples are 100% (for all glasses) and 99.93%, 100%, 100%, 100%, 100%, and 100% correspondingly. Further, beyond 0.1-0.2 MeV energy range, all C1-C6 and S1-S6 glasses RPE values are quickly decreased with enhancing photon energy, as evidenced from both Figure S11 and Figure 6, which means higher energy photons can easily pass through the samples. At 0. 15 29.45%, and 32.82%, accordingly, for S1 to S6 glasses. This indicates that, for instance, samples C6 and S6 can effectively shield only 30.73% and 32.82% of the incoming 1.5 MeV energy γ-rays and the rest of the 69.27% and 67.18% of the γ-rays can go through these glasses. Next, within the 2-15 MeV energy range, the depletion and/or variation in RPE is small for all chosen glasses, For all C1-C6 and S1-S6 samples (thickness, t = 1 cm), Figure S11 in the Supplementary Material and Figure 6 portrays variations of evaluated RPE quantities, separately. From samples C1 to C6 and S1 to S6 with improving Bi 2 O 3 content from 5 to 50 mol% and 5 to 60 mol% respectively, RPE quantities are increased owing to Bi (Z = 83), a heavy element, which boosts the glass capacity in reducing incoming photons' intensity. Here among all studied samples, glass S6 (contains 60 mol% Bi 2 O 3 ) has the relatively largest RPE at all energies. From 15 KeV up to 0.06 MeV energy, RPE has the biggest values for all glasses, indicating all samples' exceptional competence in obstructing the low energy γ-rays. As an example, the computed RPE values for C1, C2, C3, C4, C5, and C6 glasses at 15 and 60 KeV energies are 100% (for all samples) and 98.94%, 99.98%, 100%, 100%, 100%, and 100% accordingly, and these quantities at the same energies for S1, S2, S3, S4, S5, and S6 samples are 100% (for all glasses) and 99.93%, 100%, 100%, 100%, 100%, and 100% correspondingly. Further, beyond 0.1-0.2 MeV energy range, all C1-C6 and S1-S6 glasses RPE values are quickly decreased with enhancing photon energy, as evidenced from both Figure S11 and Figure 6, which means higher energy photons can easily pass through the samples. At 0. 15 29.45%, and 32.82%, accordingly, for S1 to S6 glasses. This indicates that, for instance, samples C6 and S6 can effectively shield only 30.73% and 32.82% of the incoming 1.5 MeV energy γ-rays and the rest of the 69.27% and 67.18% of the γ-rays can go through these glasses. Next, within the 2-15 MeV energy range, the depletion and/or variation in RPE is small for all chosen glasses, for example, samples C6 and S6 owns the RPE quantities 27.53% and 28.97%, 29.48% and 31.68%, accordingly, at 2 MeV and 15 MeV energies. Further, S6 glass exhibits the minimum RPE (=26.31%) for 4 MeV energy photons. Based on the RPE outputs, one can affirm that sample S6 has an excellent shielding efficiency, specifically for lower energy γ-rays, among all selected C1-C6 and S1-S6 glasses.

Sample
ΣR Reference Figure 6. Variations of radiation protection efficiency (RPE) with photon energy (MeV) for all S1-S6 glasses.
For all C1-C6 and S1-S6 glasses, the variations in 'σ T ' quantities at 1 × 10 −8 -5 × 10 −4 MeV and 6 × 10 −4 -10 MeV neutron energies, derived by applying the Geant4 code, are shown in Figure 7a-d, individually. Here inset plots of Figure 7c,d depict zoom-in neutron energy ranges at 0.075-10 MeV, respectively. At all chosen distinct neutron energies within the range of 1 × 10 −8 -5 × 10 −4 MeV, among C1-C6 and S1-S6 samples, the σ T values are increased in the order C1 > C2 > C3 > C5 > C4 > C6 and S2 > S1 > S3 > S4 > S5 > S6 (see Figure 7a,b) contingent upon the B 2 O 3 content in them. Though sample S1 possesses higher wt% of 'B' (=14.1055 wt%) than S2 glass (B: 11.2807 wt%), sample S2 owns slightly larger 'σ T ' values, which might be owing to some contribution of greater wt% of Bi (=46.727 wt%) element in it than S1 glass (Bi: 20.9742 wt%) (see Table 2). One can notice a similar result for C4 and C5 glasses 'σ T ' (i.e., C5 > C4) also (C4-B: 5.2555 wt%, Bi: 67.7275 wt%, and C5-B: 5.2402 wt%, Bi: 70.9069 wt%) (see Table 1). However, for equal molar ratio B 2 O 3 containing samples, i.e., C2 and C3 and S1 and S3, 'B' element wt% appear to solely play a principal role in the C2 and S1 samples enhanced 'σ T ' quantities than respective C3 and S3 glasses values. Besides, overall, within range of 0.01 eV-10 MeV, for all studied glasses, σ T values are decreased with increasing energy. Among all selected samples, glass C1 holds comparatively the bigger σ T values, for example, at 0.01 eV and 1 eV energies. At 0.01 eV neutron energy, 37.9099, 33.1434, 29.7834, 20.5163, 22.1935  For instance, at 600 eV neutron energy, from C1 to C6 glass, simulated σT values ar 0.5400, 0.5196, 0.5080, 0.4366, 0.4652, and 0.4277 cm −1 , whereas for S1, S2, S3, S4, S5, and S samples, they are 0.5337, 0.5579, 0.5076, 0.4783, 0.4411, and 0.3985 cm −1 , accordingly. More over, from Figure 7c,d, one can notice an acute increase in σT with a strong peak at 1 KeV energy because of an occurrence of the resonance between the neutron energy and the 'B nucleus [60] that present in all the samples. Usually, various nuclides, at a particular o For instance, at 600 eV neutron energy, from C1 to C6 glass, simulated σ T values are 0.5400, 0.5196, 0.5080, 0.4366, 0.4652, and 0.4277 cm −1 , whereas for S1, S2, S3, S4, S5, and S6 samples, they are 0.5337, 0.5579, 0.5076, 0.4783, 0.4411, and 0.3985 cm −1 , accordingly. Moreover, from Figure 7c,d, one can notice an acute increase in σ T with a strong peak at 1 KeV energy because of an occurrence of the resonance between the neutron energy and the 'Bi' nucleus [60] that present in all the samples. Usually, various nuclides, at a particular or pretty limited neutron energy region, possess the large ability for interactions with neutrons, and consequently, higher σ T occurs at these neutron energies (i.e., intense peaks in σ T against energy figures) [61]. From samples C1 to C6 and S1 to S6, with increasing Bi 2 O 3 content in the glasses, the σ T for the identified 'Bi' resonance peak at 1 KeV progressively increases, having maximal values for C6 and S6 samples in related glass series, where again glass S6 has the larger σ T than C6 sample (C6-Bi: 78.4356 wt%, S6-Bi: 80.6813 wt%) (see Tables 1 and 2 Further, applying related formula reported in Ref. [45], for all C1-C6 and S1-S6 glasses, at 0.0253 eV neutron energy, 'σ cs ', 'σ ics ', 'σ A ', and 'σ T ' are assessed and corresponding quantities are listed in Table S17i,ii of the Supplementary Material, respectively. Also, Table S18 in the Supplementary Material presents all the B, Bi, Ca, Sr, and O elements 'σ cs ', 'σ ics ', 'σ A ', and 'σ T ' values, which are contained in C1-C6 and S1-S6 glasses. Relying on Tables S17 and S18 data, one can observe that in all studied samples, C1 glass exhibits relatively bigger 'σ T ' for thermal neutrons' absorption, followed by the S2 sample. Also, obtained 'σ T ' values of all samples nicely coincide with 0.03 eV energy neutrons 'σ T ' results simulated by Geant4 for them. Finally, computational techniques, such as Geant4 and MC-NPX, are promising because of relevant data availability in large size for designing complex media and novel structures. These simulation processes are also useful to determine µ/ρ for distinct radiation shields at various energies and can be chosen as best scenarios in place of experimental procedures. Interestingly, compared to 'S6 (20SrO-60Bi 2 O 3 -20B 2 O 3 (mol%)) glass reported by Sayyed et al. [62], in our work, 'S6 (30B 2 O 3 -60Bi 2 O 3 -10SrO (mol%)) sample possesses superior photon and neutron (Σ R = 0.10521 cm −1 [62]) attenuation factors owing to its relatively larger 'ρ' ['S6 glass 'ρ' = 6.892 g/cm 3 [62]]. This establishes a fact that by simply tuning the glass composition with the same components one can achieve more favorable shielding qualities through obtaining bigger 'ρ'.