Abstract
This study loaded Bi/Bi
2
O
3
on the surface of reduced graphene oxide (rGO) to perform a two-step facile synthesis of rGO@Bi/Bi
2
O
3
as a bismuth-based nanocomposite. First, Bi/Bi2O3 ...nanocomposites were synthesised via a solvothermal process using Bi(NO
3
)
3
5H
2
O as the Bi
3+
precursor and dimethyl sulfoxide (DMSO) as the solvent. Second, we exfoliated rGO in water to functionalise Bi/Bi2O3 with a few layers of rGO. Obtained nanocomposites were characterised with scanning electron microscopy and X-ray diffraction. We also measured the nanocomposites’ photocatalytic activity using cationic dyes, specifically methylene blue (MB) and rhodamine B (RhB). Additionally, ultraviolet-visible spectroscopy was used to determine the optical properties of rGO@Bi/Bi
2
O
3
. Photodegradation was recorded under differing durations of exposure to visible light. Reaction rates were recorded at 14.6 × 10
–4
min
−1
and 22.2 × 10
–3
min
−1
for MB and RhB, respectively, while photodegradation efficiency was logged at 17% and 81%.
The direct influence of La
ions on the gamma-ray shielding properties of cobalt-doped heavy metal borate glasses with the chemical formula 0.3CoO-(80-x)B
O
-19.7PbO-xLa
O
: x = 0, 0.5, 1, 1.5, and 2 ...mol% was examined herein. Several significant radiation shielding parameters were evaluated. The glass density was increased from 3.11 to 3.36 g/cm
with increasing La
ion content from 0 to 2 mol%. The S5 glass sample, which contained the highest concentration of La
ions (2 mol%), had the maximum linear (μ) and mass (μ
) attenuation coefficients for all photon energies entering, while the S1 glass sample free of La
ions possessed the minimum values of μ and μ
. Both the half value layer (T
) and tenth value layer (TVL) of all investigated glasses showed a similar trend of (T
, TVL)
> (T
, TVL)
> (T
, TVL)
> (T
, TVL)
> (T
, TVL)
. Our results revealed that the S5 sample had the highest effective atomic number (Z
) values over the whole range of gamma-ray energy. S5 had the lowest exposure (EBF) and energy absorption (EABF) build-up factor values across the whole photon energy and penetration depth range. Our findings give a strong indication of the S5 sample's superior gamma-ray shielding characteristics due to the highest contribution of lanthanum oxide.
Using advanced Monte Carlo simulation techniques and theoretical methodologies, a thorough investigation on the gamma-ray shielding properties of several heavy metal oxide glasses were performed. The ...general-purpose Monte Carlo code MCNPX (version 2.7.0) was used to simulate gamma-ray transmission to determine fundamental attenuation coefficients. The acquired findings were compared to Phy-X/PSD to confirm that the outputs were consistent. Additionally, other gamma-ray shielding parameters were computed and studied throughout a broad photon energy range of 0.015 MeV–15 MeV. From A to F glass samples, a sharp density increase from 5.99 g/cm3 to 8.9 g/cm3 was found. As a result, the F sample was found to have the highest linear attenuation coefficients. Our results indicate that increasing the amount of Bi reinforcement improved the material's overall gamma-ray attenuation properties. The F sample with the highest Bi reinforcement in its glass structure was subsequently shown to have superior gamma-ray shielding characteristics. Finally, we compared the F sample's half-value layer values to those of other commercial glass shields, various concretes, and other glass shields investigated in the literature. As a consequence of the benchmarking procedure, it has been determined that the F sample has better shielding capabilities than other shielding materials. It can be concluded that heavy metal oxide glasses offer apparent benefits in terms of more efficiently attenuating incoming gamma-rays. Additionally, it can be concluded that applying high Bi to heavy metal oxide glasses is a beneficial strategy for improving the gamma-ray attenuation capabilities of heavy metal oxide glasses.
We aimed to determine the contribution of various trivalent ions like Al and rare-earths (Y, Nd, Sm, Eu) on resistance behaviors of different types of bismo-borate glasses. Accordingly, eight ...different bismuth borate glasses from the system: 40Bi2O3–59B2O3–1Tv2O3 (where Tv = Al, Y, Nd, Sm, and Eu) and three glasses of (40Bi2O3–60B2O3; 37.5Bi2O3–62.5B2O3; and 38Bi2O3–60B2O3–2Al2O3) compositions were extensively investigated in terms of their nuclear attenuation shielding properties, along with effective conductivity and buildup factors. The Py-MLBUF online platform was also utilized for determination of some essential parameters. Next, attenuation coefficients, along with half and tenth value layers, have been determined in the 0.015 MeV–15 MeV photon energy range. Moreover, effective atomic numbers and effective atomic weight, along with exposure and energy absorption buildup factors, were determined in the same energy range. The result showed that the type of trivalent ion has a direct effect on behaviors of bismo-borate glasses against ionizing gamma-rays. As incident photon energy increases, the effective thermal conductivity decreases rapidly, especially in the low energy range, where photoelectric effects dominate the photon–matter interaction. Sample 8 had the minimum heat conductivity at low photon energies; our findings showed that Eu-reinforced bismo-borate glass composition, namely 40Bi2O3–59B2O3–1Eu2O3, with a glass density of 6.328 g/cm3 had superior gamma-ray attenuation properties. These outcomes would be useful for the scientific community to observe the most suitable additive rareearth type and related glass composition for providing the aforementioned shielding properties, in terms of needs and utilization requirements.
In this paper, borosilicate glasses with varying concentrations of sodium oxide were synthesized using the melt-quenching method. The amorphous nature of the glasses under investigation, with a ...composition of (20 + x)Na2O-(60-x)B2O3–20SiO2 (where x = 0, 3, 5, 7, 8, 10, 13, 15, 17, and 20 mol%), was confirmed through X-ray diffraction (XRD) analysis. Fourier-transform infrared (FT-IR) spectroscopy was employed to analyze the glasses and revealed an increase in the concentration of non-bridging oxygen atoms (NBO) with increasing amounts of Na2O. The N4 parameter, which represents the fraction of NBOs, was calculated and found to decrease from 74% to 52% as the concentration of Na2O increased. The density of the glasses increased from 2.391 g/cm3 to 2.744 g/cm3 when B2O3 was replaced with Na2O, while the molar volume decreased from 27.68 cm3/mol to 23.56 cm3/mol. Theoretically, theoretical calculations were performed using newly developed computer software called Phys-PSD to assess their shielding properties, including attenuation coefficients, half value layer, and buildup factors. The calculations were conducted in the energy range of 0.015–15 MeV. The results indicated that the synthesized glasses exhibited promising potential as radiation shields.
Lifetime lung cancer risks were computed using EPA/BEIR-VI models employing recent North Cyprus statistics (4-year averages from 2012 to 2016) to address public concerns about radon risk. The excess ...relative risk, the lifetime risk of lung cancer (Re), and lifetime relative risk were estimated in the Nicosia population for both genders of non-smoker and smokers. The excess relative risk average value for age < 55 y, 55 y ≤ age ≤ 64 y, 65 y ≤ age ≤ 74 y, and age ≥ 75 y groups were 0.38, 0.23, 0.13, and 0.04, respectively.
In this study, three different sliding bearing alloy samples were investigated in terms of their performance on attenuation characteristics and behavioral attitudes under 0.015-15 MeV gamma-ray ...exposure. Accordingly, different types of advanced calculation methods were utilized to calculate the radiation shielding parameters. Next, several gamma-ray shielding parameters and exposure rates in addition to fast neutron removal cross-section were determined. Furthermore, exposure and energy absorption buildup factors were determined by using G-P fitting method. Mass attenuation coefficients (MAC) values were recorded as 2.5246, 2.5703, and 2.5827 (cm
/g) for Alloy1, Alloy2, and Alloy3 samples at 15 MeV photon energy, respectively. At 40 mfp, the highest EBF values were reported as 1,376,274, 1,003,593, and 969,373 for Alloy1, Alloy2, and Alloy3 samples. The results of this extended investigation showed that the Alloy3 sample with the highest Pb reinforcement amount has superior shielding capability among the investigated samples. It can be concluded from the results that substitution of Pb with Bi in the recent alloy structure has a monotonic effect on different types of shielding parameters. Therefore, it can also be concluded that Pb is a remarkable tool for the improvement of the shielding properties of studied alloy structures.
Salen ligands are essential for coordinating a diverse group of metals in their respective oxidation states. This creates significant complexes of salen metals that are used in different fields. ...Condensation of ehylenediamine (en) with p-methoxybenzaldehyde (L1) or o-hydroxyacetophenone (L2) with a ratio 1: 2 (en: p-methoxybenzaldehyde or o-hydroxyacetophenone) or by the interaction of o-phenylenediamine (phen) with o-hydroxybenzaldehyde (L3) or p-hydroxybenzaldehyde (L4) with a ratio 1: 2 (phen: o-hydroxybenzaldehyde or p-hydroxybenzaldehyde) has been used to prepare four symmetrical Schiff bases (L1-L4). The UV–vis spectroscopy has been used to investigate the diverse electronic transitions associated with the Schiff bases molecules as well as how these transitions are impacted by diverse polarities of solvents. Elemental analysis, FT-IR, UV–vis spectra, molar conductivity, and 1H NMR have been used to characterise all the compounds obtained in this process. The continuous variation applied alongside molar ratio spectral methods showed the formation of different complexes arising from the reaction of the ligand (L1-L4) with the metal ions Mn(II), Fe(III) and Cu(II) is 1: 1 and/ or 1: 2 (M: L). A series of universal buffer solutions (20 % ethanol v/v) with varying pH values were used in spectrophotometry to determine the acid dissociation constants of the L2 and L4 ligands. Gamma radiation was applied to examine the compounds’ irradiation stability. Additionally, the absorptions of the main functional groups were screened using FT-IR spectra before and after Gamma irradiation. The results show that all the compounds are stable after irradiation process; therefore, it could be used as enhancing agents in cancer therapy.
Characteristics of tellurite-tungstate-antimonate glasses containing heavy metal oxide were investigated in detail using two methods: the MCNPX Monte Carlo code and the Phy-X/PSD platform. The ...influence of Sm2O3, translocating with TeO2 at ratios of 0.2, 0.5, 0.8, 1, and 1.5 mol% on radiation shielding properties of glasses, was set forth with five glass structures determined according to the (75-x)TeO2-15Sb2O3-10WO3-xSm2O3 glass composition. Densities of the glasses were prepared by doping a low ratio of Sm2O3 that varied between 5.834 and 5.898 g/cm3. Sample densities, which have an important role in determining radiation shielding character, increased depending on the increase in Sm2O3 concentration. Effective removal cross-section (∑R) values against fast neutrons, as well as linear and mass attenuation coefficients, half-value layer, mean free path, variation of effective atomic number against photon energy, exposure, and energy built-up factors, were simulated with the help of these two methods. As a result of these estimates, it can be concluded that values obtained using both methods are consistent with each other. From the obtained values, it can be concluded that the SM1.5 sample containing 1.5 mol% would have the most efficient role in radiation shielding. An increase of Sm2O3 resulted in a significant increase in linear and mass attenuation coefficients and effective removal cross-section values belonging to fast neutrons and, in addition, resulted in a decrease in the half value layer. Doping HMO glasses with Sm2O3 was observed to contribute directly to the development of radiation shielding properties of the glass.
The goal of this investigation is to test the barium boro-silicate glass-ceramics with different additives against gamma radiation using the FLUKA Monte Carlo code. On four different glass-ceramics ...samples, the effect of an equal quantity of Al2O3, La2O3, Gd2O3, and Dy2O3 with barium borosilicate glass-ceramics on the radiation shielding capabilities of the glass-ceramics was investigated. In the examined glass ceramics, densities were obtained to investigate glass samples. The densities obtained were 3.92, 4.432, 4.52, and 4.88 g/cm3, respectively. BBSDy sample has the highest density which indicates that it is more effective for radiation shielding. The shielding parameters have been calculated at 0.356, 0.662, 1.173, and 1.333 MeV. The obtained results have been compared with the NistXCOM web page and Phy-X/PSD platform. The results showed a good agreement between FLUKA code, NistXCOM, and Phy-X/PSD. The calculated shielding parameters increase with additive (Al2O3, La2O3, Gd2O3, and Dy2O3). Moreover, the 50BaO–15SiO2–30B2O3–5Al2O3-5Dy2O3 specimen has the best radiation shielding features among the other glass-ceramics. In conclusion, the BBSDY sample containing 5 mol per cent 5 mol% Dy–III–Oxide would be the most effective in terms of radiation shielding, based on the results obtained in this study. When Dy-III Oxide concentrations were increased, linear and mass attenuation coefficient values were significantly increased, which contributed directly to the development of radiation shielding characteristics in the glass-ceramic.
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