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For 662, 1173, 1275, and 1333 keV gamma-ray energy, photon transmissions, linear attenuation coefficients, half value layer, tenth value layer, and mean free path values of bismuth-borophosphate glasses were measured experimentally. Then, the measured findings were compared to the FLUKA code. The FLUKA code findings agreed well with the experimental results. Furthermore, the findings show that adding Bi2O3 to the glass network improves the shielding properties. The current data reveal that when the Bi2O3 content rises, so does the absorbance. Furthermore, the optical constants of the present gasses, such as optical band gap, phonon energy, and tails of localized states, were examined. Fourier transform infrared (FTIR) spectrometer was used to analyze the Fourier transform infrared (FTIR) spectra of our samples at room temperature in the 4000–400 cm−1 wavenumber range. From a shielding standpoint, bismuth-borophosphate glasses offer excellent gamma-ray shielding properties. © 2022

The optical absorption, FTIR and EPR spectra as well as the absorption dispersion parameters such as optical energy gap and urbach energy were studied. A series of 0.7% transition metal oxides (Ti, V, Cr, Fe) doped 70% B2O3–30% Bi2O3 glasses were prepared using conventional melting process. The valence states of TM ions and their coordination in the glass network have been investigated. FTIR spectra show that a gradual conversion of BO4 tetrahedral units into BO3 trigonal units in the glass network after irradiation (50 kGy) leading to the formation of non-bridging oxygen’s. The optical absorption and EPR studies suggest that, the TM-ions exist in the octahedral state and act as modifiers by increasing the degree of disorder in the glass network. Also, there is no remarkable change in the signal after irradiation which strongly recommended these glasses to be used as gamma radiation shielding.

Structural, optical and electrical properties of developed (P2O5)47-(Na2O)23-(Al2O3)6-PbO(24−x)-(Sm2O3)x (where x = 0.5, 1 and 3 mol%) at different gamma irradiation doses (0, 10, 50 KGy) have been investigated. Melt-quenching method was used for synthesizing these glasses. XRD observations provide for the ampophosity of the as-prepared glasses. The effect of different gamma irradiation doses and Sm2O3 contents affect crystallinity of the developed samples. Moreover, the results show a decreasing in the transmittance light as the gamma doses increase from 0 to 50 kGy. The both calculated direct and indirect optical band gap were found to be affected by gamma irradiation doses for (P2O5)47-(Na2O)23-(Al2O3)6-PbO(24−x)-(Sm2O3)x. On the other hand, the electrical activation energy and electrical conductivity of the glasses were affected by gamma irradiation doses for (P2O5)47-(Na2O)23-(Al2O3)6-PbO(24−x)-(Sm2O3)x (where x = 0.5, 1 and 3 mol%). These various studies forces to fabricate a glass material that could be utilized to attenuate or reduce gamma-radiation.

In this study we compared the effect of three different concentrations of MoO3 on the corrosion of sodium phosphate glass containing lead and aluminum oxides to develop its durability. The corrosion was studied in deionized water and acidic solution of 0.1 N HCl. The dissolution mechanism is interpreted depending on the glass weight loss versus time and change in the glass surface. MoO3 had a stabilizing effect on the glass, causing a decrease in the glass dissolution rate. Acidic medium was found to strongly enhance the glass dissolution. The pH decrease in water with increase in acidic solution gives evidence of the release of some phosphorous ions to form phosphoric acid. The consequent enhancement of the glass durability was influenced by the presence of MoO3 and showed a remarkable advance by doping with 3 wt% of MoO3. FT-infrared absorption spectra of the studied glasses show IR vibrational bands due to phosphate groups mainly of the metaphosphate and pyrophosphate units together with the sharing and interference of IR vibrations due to Pb–O bonds. Gamma irradiation produces a minor effect on the IR spectra, and enhances the base glass durability at the beginning of the corrosion process, which can be related to the shielding behavior of the high lead glass. However, glass containing 3% MoO3 has the best durability and is the least affected by irradiation. The glass durability corresponding to its structure is verified by IR spectroscopy.

A recycled commercial glass sample doped small amounts of cobalt to give blue glass. A change in its color upon being exposed to gamma-radiation according to the irradiation doses has been identified. The effect of irradiation on the optical, thermal and electrical properties of the glass is studied. The optical, properties of the irradiated glasses vary significantly from those of the unirradiated glasses. All the peaks intensity increased with the increase of the irradiation doses except the peak at 280 nm where it is shifted to a higher wavelength upon irradiation, but its intensity decreased at the highest irradiation dose of 100 kGy. The optical energy band gap decreased with the increase of the irradiation dose for both direct and indirect Eg. FTIR spectra reveal IR vibrational bands which are characteristics to the three specific characteristic structural building units within the silicate glasses. The absorbance of peaks at 960, 1015 cm−1, which represents stretching NBOs (SiO2) and stretching of bridging oxygen (SiO4) respectively have been tracked. The increase of the band at 960 cm−1 can be stated to the increase in the amount of NBOs, when the glass samples are exposed to gamma irradiation. The thermal study showed that both Tg and Tc increased progressively upon irradiation. The increase in dielectric conductivity (DC) as the irradiation doses increase is attributed to the effect of ionizing radiation, which induces a photo-oxidation due to the excitation of the electrons in the lower valence. The obtained glasses seem to be promising materials and can be used in accident dosimetry applications or as potential dosimeter.

Un-doped and cobalt oxide (CoO) doped lithium borate glasses with different concentrations (0.1, 0.3, and 0.5 mol %) were prepared by the conventional melting process at an approximate temperature of 1100 °C. The X-ray diffraction analysis showed the amorphous structure of the prepared glasses. Fourier transform infrared (FTIR) spectra of the synthesized glasses proved a gradual change in the glass network due to the transformation of the trigonal BO3 units into the tetrahedral BO4 units with the formation of non-bridging oxygens with the increase of CoO concentration and irradiation dose to 60 kGy. Minor changes occurred in the vibration bands of the FTIR spectra of lithium borate glasses with the increase of CoO concentration, where a slight lowering and broadening in the already existed peaks for BO3 and BO4 can be observed indicating the well dissolved of CoO in the glass matrix. The optical absorption spectra of the glasses before and after electron beam irradiation with different doses have been studied and the optical band gap, Urbach energy and refractive index also have been obtained. The results showed broad and strong absorption peaks in the visible range; these peaks can be attributed to the presence of the cobalt ions in the octahedral and tetrahedral configurations with different valence states. It is observed that the prepared glasses have a high sensitivity to electron beam irradiation which makes these glasses applicable to be used as dosimeters especially with low doses.

Commercial glass with composition SiO2 ≈ 71.9, Na2O ≈ 14.25, CaO ≈ 8.6, MgO ≈ 4.05, Al2O3 ≈ 0.66, K2O ≈ 0.037, TiO2 ≈ 0.025, Fe2O3 ≈ 0.08, SO3 ≈ 0.32 mixed with X CuO (X ≥ 0.01) were synthesized by melt-casting method. After that, effects of gamma ray on glass samples were investigated by optical absorption, transmission %, FTIR and ESR spectra. The optical absorption and ESR studies suggested that, Cu-ions exist as Cu2+ valence state and act as modifiers by raising the degree of disorder in the glass network. Physical parameters such as optical energy gap (Eopt), Urbach energy (Eu), refractive index (n) and electrical constant were also calculated to sustain the results obtained from optical absorption measurements. Results show that there are considerable variations in number of NBOs in the structural glass due to the influence of CuO and gamma irradiation. Calibration curve of Commercial window glass containing 0.05 mol % CuO exhibited dosimeter behavior in long dose range among 2.5–80 kGy. Also, characteristic fading curve over a period of 50 days at room temperature has been taken into consideration. Our study showed that the recycled commercial window glass doped with 0.05% CuO could be candidate for radiation dosimeter application.

Bismuth borate glasses doped 0.7% of one of the following transition metals Cu, Co, Ni was prepared using traditional melt quenching technique. Some physical characters of the prepared glass such as UV transmission and electrical conductivity were measured. The results showed that seven peaks were found at 255, 270, 311, 330, 355, 390 and 409 nm. The transmission% decreased by subjecting glass samples to gamma irradiation (2.5 and 5 kGy) then no further change can be observed with the increase of the irradiation dose up to 50 kGy. Results also showed that both band gap and electronegativity decreased by the addition of transition metals. Effects of different doped transition metals and gamma irradiation doses on the electrical conductivity of bismuth borate glasses were examined. However, refractive index, electron and molar polarizability increased with the presence of transition metals. Furthermore, mass attenuation coefficient, effective atomic number, half value layer and radiation protection efficiency were calculated. Comparing experimentally shielding parameters with those calculated using XCOM program showing good compatibility. The results showed that glass containing Cu has the best shielding results for photon energy range (1–10 MeV).

The irradiation of Cu-doped Cd-phosphate glass mediated by gamma rays shows the conversion of Cu2+ ↔ Cu+ ion with subsequent glass defects which leads to the loss of glass structure. The physical evaluations encompassing FTIR studies, X-ray diffraction analysis, UV spectrophotometer analysis, EPR, differential scanning colorimetry, and elastic properties are performed. The optical band gap (Eg) values for both direct and indirect transition and refractive index are evaluated for varying irradiation doses and correlated with the data obtained for optical spectra, ultrasonic wave velocities and elastic moduli. Further, the evaluations such as optical basicity and average electro negativity have been determined. The obtained optical basicity values increases with concurrent increase in the dose of radiation, however the values of electron negativity have not displayed such variations. After irradiation at various doses, there is a significant elevation in non-bridging oxygen (NBO) atoms which lead to decreased glass polymerization, reduced glass stability and aids the formation of copper ions aggregates. The above stated process highly alters the structure and optical properties of glass which is confirmed by the results of the optical absorption, FTIR and EPR spectral analysis. The force constant values and the bond strength between Cu–O are lower as compared to P–O, which further decreases the glass rigidity thus decrease in glass rigidity affects the ultrasonic velocity, Eg and Tg. The thermal stability values of studied glass decreased with subsequent increases in the dose of irradiation. Thus this glass displays specific optical characteristic and thus can be employed as a bandpass filters.

Changes of FTIR, UV–Visible spectra, photoluminescence with varying Sm content in phosphate glass containing sodium, lead and aluminum were studied. Refractive index values have been measured and their values were listed to be between ~ 1.5–1.7. Furthermore the effect of subjecting this glass to gamma rays was also investigated. The results showed that glass containing 1%Sm had the highest NBOs according to FTIR, UV-Visble results. The optical energy band gap and Urbach values supported this assumption. The presence of Sm3+ which can be reduced to Sm2+ in addition to the NBOs produced due to the addition of Sm ions in the glass matrix, causing a reduction of gamma rays effect. This may give a clue to the ability of using this glass as an immobilizer or shielded for gamma rays or as a burial for high energy radioactive materials.