Bismuth Borate Glasses Research Articles

Probing of nuclear radiation attenuation and mechanical features for lithium bismuth borate glasses with improving Bi2O3 content for B2O3 + Li2O amounts

Against photon energies extending from 0.015 to 15 MeV, MCNPX, FLUKA and PHITS codes are operated to simulate mass attenuation coefficients (μ/ρ) for a total of ten B2O3-Bi2O3-Li2O glass compositions with added Bi2O3 amount from 10 to 55 mol% (5 mol% growth gradually) as a substitute for total (B2O3 + Li2O) mol% content. All the computed μ/ρ values correctness is examined by Py-MLBUF and WinXCOM programs’ μ/ρ outcomes and we found a good agreement among them. 55Bi2O3-35B2O3-10Li2O (mol%) glass half-value layer (HVL) and mean free path (MFP) quantities are compared with distinct commercial γ-ray attenuating glasses, alloys, polymers, concretes and lead and ceramics corresponding values. Next, equivalent atomic numbers (Zeq) and by employing geometric progression (G–P) fitting method at 1–40 mfp PDs (penetration depths), at 0.015–15 MeV energy range ‘buildup factors’ were calculated. At all chosen twenty-five energies derived radiation protection efficiency (RPE) results assured investigated samples exemplary competence for low energy photons absorption. Applying SRIM codes ΨP and ΦP and ΨA and ΦA (mass stopping powers (MSPs) and projected ranges (PRs) for protons and α-particles), and making use of ESTAR database ΨE (electron MSP) and continuous slowing‐down approximation (CSDA) range for electrons are determined at KE (kinetic energy) range of 0.015–15 MeV. Moreover, fast neutron removal cross-sections (ΣR), for 0.0253 eV energy neutrons absorption cross-sections have been estimated. Deduced ΣR was altered at 0.1105–0.1205 cm−1 range with Bi2O3 inclusion in studied samples. 10Bi2O3-70B2O3-20Li2O (mol%) glass has greater total cross-section (=23.251 cm−1) for thermal neutrons absorption while 55Bi2O3-35B2O3-10Li2O (mol%) sample exhibits quality shielding factors for photons and fast neutrons confirming the included Bi2O3 positive impact. Along with nuclear attenuation features various physical and mechanical aspects are also inspected. Derived Vm (molar volume), OPD (oxygen packing density), Vo (oxygen molar volume), Vt (packing density) and Gt (dissociation energy per unit volume) values indicated glasses rigidity. Following Makishima–Mackenzie's theoretical model primary mechanical features like Y, K, S and L (Young's, bulk, shear and longitudinal modulus) and σ (Poisson's ratio) are evaluated where 10Bi2O3-70B2O3-20Li2O (mol%) glass shows better elastic moduli in all samples.

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.

Characterization of optical and radiation shielding behaviors of ferric oxide reinforced bismuth borate glass

This study aimed to investigate the ferric oxide effect on optical and radiation shielding behaviors of bismuth borate glasses. Gamma-ray attenuation competencies of six glass samples along with optical properties were investigated in terms of their utilization suitability as a shield or personal protection equipment in industrial and medical fields. The chemical composition (60-x) B2O3 + 20Bi2O3 + 20Li2O+xFe2O3 with different Fe2O3 concentrations were prepared using the melt-quenching technique. Gamma-ray attenuation competencies of six glass samples along with optical properties were investigated in terms of their utilization suitability in industrial and medical fields. The outcomes of optical investigations indicated that direct optical band gap (Eg direct) decrease from 5.11 eV to 4.82 eV, while for indirect transition (Eg indirect) decrease from 4.62 eV to 3.79 eV, with increasing Fe2O3 concentrations. To determine the radiation shielding performance, mass attenuation coefficients (μ m) of samples were calculated using FLUKA code and XCOM program between 0.015–15 MeV photon energy range. Accordingly, gamma shielding parameters such as mass (MAC) and linear (LAC) attenuation coefficients, half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic numbers (Zeff), electron density (Nel), and fast neutron removal cross sections (ΣR) were evaluated for all glass samples. The results showed that increasing Fe2O3 concentration in glass structure increased the MAC and Zeff. The Fe-10 was reported with the lowest HVL values in addition to the highest MAC and Zeff values.

Tailoring bismuth borate glasses by incorporating PbO/GeO2 for protection against nuclear radiation

Nuclear radiation shielding capabilities for a glass series 20Bi2O3 − xPbO − (80 − 2x)B2O3 − xGeO2 (where x = 5, 10, 20, and 30 mol%) have been investigated using the Phy-X/PSD software and Monte Carlo N-Particle transport code. The mass attenuation coefficients (μm) of selected samples have been estimated through XCOM dependent Phy-X/PSD program and MCNP-5 code in the photon-energy range 0.015–15 MeV. So obtained μm values are used to calculate other γ-ray shielding parameters such as half-value layer (HVL), mean-free-path (MFP), etc. The calculated μm values were found to be 71.20 cm2/g, 76.03 cm2/g, 84.24 cm2/g, and 90.94 cm2/g for four glasses S1 to S4, respectively. The effective atomic number (Zeff)values vary between 69.87 and 17.11 for S1 or 75.66 and 29.11 for S4 over 0.05–15 MeV of photon-energy. Sample S4, which has a larger PbO/GeO2 of 30 mol% in the bismuth-borate glass, possesses the lowest MFP and HVL, providing higher radiation protection efficiency compared to all other combinations. It shows outperformance while compared the calculated parameters (HVL and MFP) with the commercial shielding glasses, different alloys, polymers, standard shielding concretes, and ceramics. Geometric Progression (G-P) was applied for evaluating the energy absorption and exposure buildup factors at energies 0.015–15 MeV with penetration depths up to 40 mfp. The buildup factors showed dependence on the MFP and photon-energy as well. The studied samples' neutron shielding behavior was also evaluated by calculating the fast neutron removal cross-section (ΣR), i.e. found to be 0.139 cm−1 for S1, 0.133 cm−1 for S2, 0.128 cm−1 for S3, and 0.12 cm−1 for S4. The results reveal a great potential for using a glass composite sample S4 in radiation protection applications.

Microstructure and mechanical property of sapphire joints reinforced byAl4B2O9 whiskers

Bismuth-borate glass, 40Bi2O3–60B2O3 (mol.%), was prepared and acted as a braze to join sapphire in air. Ahead of brazing, basic properties of glass were investigated, including structure and thermal parameters. The thermal expansion test showed that CTE of glass was 8.4 × 10−6/°C in period from 20 to 450 °C, suggesting a good thermal compatibility with sapphire. Bi45BO69 was the main crystalline phase in glass according to DSC analysis [BiO6], [BO3] and [BO4] were major units in 40Bi2O3–60B2O3 glass on the basis of FT-IR spectra analysis.In addition, the wetting behavior of the 40Bi2O3–60B2O3 glass on the sapphire substrate was favourable. Thereafter, sapphire plates were joined at 700 °C for 0 and 20 min, respectively. The results showed that Al4B2O9 whiskers grew in joint when holding for 20 min due to a reaction between 40Bi2O3–60B2O3 glass braze and sapphire. The shear strength was improved greatly as a result of Al4B2O9 whiskers’ appearance.

Gamma-ray shielding studies on borate glasses containing BaO, Bi2O3, and PbO in different concentrations

Mass attenuation coefficients (μm), half value layer (HVL), effective atomic cross sections (σa), effective atomic numbers (Zeff) and effective electron densities (Neff) of borate glasses containing different concentrations of BaO, Bi2O3, and PbO (20–50% by mole) were obtained in the energy range of 10 keV–10 MeV using MCNPX code, XCOM and XMuDat programs, Auto-Zeff software and linear interpolation method. The simulated and calculated results were in good agreement with the experimental data with differences of ≤ ± 11%. It was found that σa and Zeff of glass samples improve by increasing their BaO, PbO and Bi2O3 contents, while increasing these contents to the same fraction has no significant effect on μm values in the energy range of 0.3–6 MeV, where the Compton Effect takes over as dominant process. In addition, the μm and σa values of glasses decreased with photon energy and bismuth oxide borate glass obtained the highest values of μm and σa. Also, HVL values of the studied glasses decreased with the increase in their densities. The 50Bi2O3:50B2O3 glass system had the highest Zeff value of 55.60 at the 30 keV photon energy. Above 0.4 MeV photon energy, Neff values were independent of the metal oxides contents. The Neff values of the studied glass systems varied in the range of 2.77 × 1023 – 9.10 × 1023 electron/g.

Optical and structural studies of some zinc calcium borate glasses for optoelectronic device applications

Samples of bismuth borate glasses were prepared by the melt-quenching method, following the molar ratio formula [(58.4–2x) mol% B2O3 + (18.8 + x) mol% ZnO + (18.8 + x) mol% CaO + 4 mol% Bi2O3)], where x = 0, 2, 4, 6, and 8 and equal concentrations of zinc oxide and calcium oxide were incorporated into the glass matrix. The structural analysis of the prepared materials was characterized using X-ray diffraction measurements, where each sample showed highly homogenous glassy nature. Deconvolution of X-ray diffraction data was employed to separate unresolved bands, and results manifested the existence of two micro-nucleating agents at 2θ values about 30° and 50°. Optical and optoelectronic properties of the present glasses were assessed using the UV optical absorption. Introducing both zinc and calcium oxides increased the glass transparency for electromagnetic radiation in the UV region. Additionally, values of Fermi energy, Urbach energy, optical conductivity, and the linear refractive index were decreased by the incorporation of both zinc and calcium oxides, while the quality factor was increased. Our results suggest the studied materials for optical filtering, optical switching, and optoelectronic device applications.

Nanosecond nonlinear optical, optical limiting and gamma radiation shielding attributes of Eu3+ ions doped heavy metal borate glasses

Bismuth borate glasses activated with different Eu2O3 concentrations were synthesised by the traditional melt–quenching method. The efficacy of Eu3+ ions concentration on nanosecond third–order nonlinear optical, optical limiting and gamma radiation shielding attributes was systematically studied and discussed. The nonlinear optical and optical limiting features were studied at 532 nm excitation under nanosecond laser pulses using Z–scan technique. The two-photon absorption coefficient was enhanced from 1.55 × 10−11 to 2.37 × 10−11 m/W, the nonlinear refractive index was increased from 1.61 × 10−18 to 3.28 × 10−18 m2/W while the optical limiting threshold value was reduced from 2.451 × 109 to 0.292 × 109 J/m2 with increase in Eu2O3 concentration in the glass composition. This increase in two-photon absorption coefficient and decrease in optical limiting threshold values with respect to Eu3+ions clearly reveal the high Eu3+ containing (NBiBEu2 in the present investigation) glasses are beneficial for the construction of power optical limiters to work in visible (532 nm) spectral region under nanosecond regime. The radiation attenuation factors were determined between 0.276 and 1.275 MeV using Phy–X program. The linear attenuation coefficient (LAC) varied between 0.375 and 0.377 cm−1 at 0.276 MeV, and the maximum LAC was reported at this energy. With further increase in the energy, we found that the attenuation competence of the prepared glasses begins to weaken, and the lowest attenuation ability was found at 1.275 MeV. The effective atomic number (Zeff) was computed, and we found that the Zeff follows the order: NBiBEu2> NBiBEu1.5> NBiBEu1> NBiBEu0.5> NBiBEu0. The tenth value layer (TVL) for NBiBEu0 increases from 1.001 cm at 0.276 MeV, to 1.600 cm at 0.356 MeV, to 2.750 cm at 0.511 MeV and to 6.545 cm at 1.275 MeV.

Research on the effects of bismuth borate glass system on nuclear radiation shielding parameters

There has been an increasing number of research and development activities focusing on the use of different glass systems for their nuclear radiation shielding features. In this study a simulation study has been carried out at a wide photon energy region in order to investigate the radiation protection feature of bismuth borate glasses. This study has been conducted to evaluate the proficiency level of six different glass systems (70-x)B2O3 + xBi2O3 + 15ZnO + 15Na2O (where x = 0, 5, 10, 15, 20 and 25 mol%) exposed to photon, charged particle (H1) and (He+2) and neutron. For this investigation, transmission factors (TF), mass attenuation coefficient (MAC), half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff), effective electron density (Neff) have been computed. The results confirm that the parameters of the examined glasses MAC, HVL, TVL, MFP, Zeff, and Neff are associated with photon energy and chemical composition. In addition, neutron effective cross-sections (∑R) have been computed for bismuth borates and it was seen a good harmony. The computations for present samples have been examined over a broad energy range from 0.01 to 20 MeV and theoretical results have been obtained by using MCNPX software for transmission factors. In addition, simulation results have been calculated with the WinXCom program. Furthermore, MSP and PR calculations of the bismuth borate glass have been performed to figure out the radiation shielding features. For that reason, the SRIM code has been used to simulate H1 and He+2 particles. Considering the results obtained from this research, which examines the radiation protection of bismuth borate glasses, indicates that the best shielding achievement (while the HVL, TVL, MFP, TF have the lowest and the highest (∑R) values) is reached at 25% Bi2O3. As can be seen in the results, the addition of bismuth affirms that the use of such glass systems improves the radiation protection feature. In particular, 25%Bi2O3 glass system has been proved to show superior shielding properties for gamma radiation in combination with charged particles. Since the glass sample with the highest bismuth additive is 25%Bi2O3, the most radiation protection effect is also seen in this example. The obtained material has a satisfactory radiation shielding property as bismuth is added to the mixture.

Short-range structure, the role of bismuth and property-structure correlations in bismuth borate glasses.

Bismuth-containing borate glasses, xBi2O3-(1 - x)B2O3, were synthesized in the broad composition range 0.20 ≤ x ≤ 0.80 by melting in Pt crucibles and splat-quenching between two metal blocks. Infrared reflectance spectra, measured in the range 30-5000 cm-1, were transformed into absorption coefficient spectra and then deconvoluted into component bands to probe the glass structure as a function of composition. Integrated intensities of bands above 800 cm-1 were used in combination with mass and charge balance equations to quantify the short-range borate structure in terms of the molar fractions X4m, X4o, X3, X2, X1 and X0 for borate units BØ4-, BØ2O23-, BØ3, BØ2O-, BØO22- and BO33-, where Ø and O- denote bridging and non-bridging oxygen atoms. Borate tetrahedral units were found to be present in both the meta-borate, BØ4-, and ortho-borate, BØ2O23-, forms with BØ4- constituting the dominating tetrahedral species for 0.20 ≤ x ≤ 0.70. The BØ2O23- units prevail at higher Bi2O3 levels (x > 0.7), and coexist with their isomeric triangular borate species BO33- (BØ2O23- ⇌ BO33-). The present IR results for the total molar fraction of borate tetrahedral units, X4 = X4m + X4o, are in very good agreement with reported NMR results for the fraction of boron atoms in four-fold coordination, N4. Besides evaluating X4m and X4o, the present work reports also for the first time the fractions of all types of triangular borate species X3-n with n = 0, 1, 2 and 3. The IR region below 550 cm-1 was found to be dominated by the Bi-O vibrational activity in coexisting ionic (160-230 cm-1) and distorted BiO6 sites (330-365 cm-1 and 475-510 cm-1), a result reflecting the dual role of Bi2O3 as glass-modifier and glass-former oxide. The latter role dominates in glasses exceeding 60 mol% Bi2O3, and is consistent with the extended glass formation in the bismuth-borate system. The structural results were used to calculate the average number of bridging B-Ø bonds per boron center, the average Bi-O and B-O single bond energy, and the atomic packing density of the studied glasses. These properties vary approximately linearly with Bi2O3 content in the three regimes 0.2 ≤ x ≤ 0.4, 0.4 < x ≤ 0.6 and 0.6 < x ≤ 0.83, and contribute collectively to the composition dependence of glass transition temperature.

Investigation of optical and physical properties of zinc sodium bismuth borate glass system

A glass system with composition xZnO-(15-x)Na2O-15Bi2O3-70B2O3 (where x=0, 6, 8, 10, 12 mol %) have been prepared by conventional melt quenching technique in order to investigate the some physical and optical properties with impact of ZnO in the sodium bismuth borate glasses. The optical analysis of glass system is carried out by UV-Vis spectroscopic measurement technique. The optical study reveal that cut off wavelength and Urbach energy decreases while optical band gap increases with the addition of ZnO content. Further, the compositional dependence of different physical and optical parameters such as ion concentration, polaron radii, inter nuclear distance, molar refraction, molar polarizability, reflection loss, metallization criterion, refractive index and dielectric constant have also been evaluated.

Physical properties and gamma radiation shielding capability of highly dense binary bismuth borate glasses

Dense glasses in the binary bismuth-borate system, xBi2O3-(1-x)B2O3 (BBO), x = 0.25, 0.5, & 0.75 were prepared by conventional melt-quenching process at different temperatures. The melt was hot pressed between the stainless-steel plates to obtain dense glasses. The glasses obtained were optically clear, thermally stable and amorphous in nature. Transparent BBO glasses exhibited high density in the range of 5.5–8.29 g/cm3 which is attributed to the high bismuth content and pressure induced compaction at high temperatures in the hot-pressed quenching. Gamma radiation shielding properties of the dense BBO glasses were investigated by calculating mass attenuation coefficients, effective atomic number, and different buildup factors. Radiation shielding properties were calculated using the XCOM and Phy-X web software as a function of photon energy for all the glasses. Experimental mass-attenuation coefficients at different energies of the BBO glasses were determined through radiation transmission method. Measured mass-attenuation coefficients of the BBO glasses were in close agreement with the calculated values. Further, exposure and energy absorption buildup factors of the dense BBO glasses were studied at different penetration depths as a function of the photon energy. The results were compared with the heavy-metal oxide glasses reported in the literature and with respect to lead metal shield. Dense binary bismuth glass exhibited high mass-attenuation coefficients, and low half-value layer, and mean-free path which are comparable with the metal lead. The dense binary bismuth borate glasses reported here can be the excellent radiation shielding transparent simple glass system and promising for the radiological applications.

Evaluation of physical and radiation shielding properties of Bi2O3–B2O3 glass doped transition metals ions

Bismuth borate glasses of formula 60% Bi2O3 and 40% B2O3 doped 0.7 wt % of one of the transition metal oxides; TiO2, Cr2O3, V2O5 or Fe2O3 were prepared using melting-annealing method. The glasses optical transmittance spectra have been studied and reveal UV transmission bands related to the different valence states of the doped transition metal ions. Electrical conductivity and many physical parameters of the glasses were also investigated such as; optical bandgap (Eopt), refractive index (n), reflection loss (RL), molar refractivity (Rm), molar polarizability (αm), dielectric constants (ε), optical transmission coefficient (T) and metallization criterion (M Criterion).The effectiveness of the glasses as radiation protective shield was evaluated and calculated by Monte Carlo N-Particle Transport Code (MCNP) using the Medical Internal Radiation Dose (MIRD) of male human model. Many shielding parameters have been also deliberated such as; linear attenuation coefficient, effective removal cross section (ΣR), radiation protective efficiency (RPE %), tissue weighting factors (Wt), in addition to a comparison between the experimental and the simulated linear gamma attenuation coefficients at numerous energies. The glasses reveal high stable optical and physical properties in addition to high radiation shielding efficiency against gamma irradiation. The high concentration of heavy Bi3+ ions and presence of transition metal ions with their variable configurations, provide the shielding behavior of the glasses and decreased the life time risk for cancer by about five times.

Microstructure evolution and mechanical properties of YAG/YAG joint using bismuth-borate glass

Joining of Y3Al5O12 garnet single crystal (YAG) was achieved by using a bismuth-borate based glass filler. The thermal properties of glass filler were experimentally determined and the wettability of molten glass on YAG was investigated. The YAG reacted with glass to form ZnAl2O4 particles and Y2O3 nanowires successively as joining temperature is above 625℃. ZnAl2O4 preferentially nucleated and grew on Y2O3 nanowires. The cooperative growth of the two phases accelerated YAG decomposition, which in turn led to cluster growth of Y2O3 nanowires and aggregation of ZnAl2O4 particles at elevated temperature. The microstructure evolution and reaction mechanism were studied. The highest shear strength of 29.6 ± 5.2 MPa was obtained for the joint brazed at 650℃. The fracture morphology demonstrated that the dispersive strengthening of ZnAl2O4 and stress relief by Y2O3 nanowire network contributed to the superior mechanical performance.

Investigation of Gamma‐Radiation Shielding Properties of Cadmium Bismuth Borate Glass Experimentally and by Using XCOM Program and MCNP5 Code

New glass systems of bismuth borate with various concentrations of cadmium oxide are prepared based on the melt‐quenching method. The X‐ray diffraction (XRD) reveals a fully amorphous structure of the prepared glasses (S1–S4), and the UV–vis results display good transparency (&gt;50%) in the visible and near‐UV region. In addition, the radiation shielding properties (mass attenuation coefficient, half‐value layer, tenth value layer, mean free path, effective atomic number, and electron density) of the new glass system are determined at selected energies experimentally and by using MCNP5 simulation code and XCOM computer program. Based on the calculated relative difference, the obtained values from MCNP5 and XCOM are in good agreement with the experimental data. The mean free path of the current systems (particularly S4) shows optimistic results when compared with the barite and chalcocite concretes.

Design of a functional Al2O3/Al2O3 joint for sensing the brazing seam temperature with high sensitivity

Temperature monitoring of braze seam with high sensitivity and fast response is essential for safe working of a joint. Herein, a non-contact optical thermometry for joint is designed. The Yb3+/Er3+:Y2O3 micro-crystals were prepared and mixed into bismuth borate glass to bond Al2O3 ceramics. After brazing, Y2O3 particles still preserve perfect crystal structure, and its addition widens the thickness of braze seam. The obtained shear strength of joint is up to 83.5 MPa. Under 980 nm excitation, 2H11/2 and 4S3/2 levels of Er3+ ion in braze seam are thermally coupled levels and show excellent temperature dependent characteristic. The temperature sensing sensitivity is superior and the maximum values of absolute sensitivity and relative sensitivity are 0.0182 K-1 and 0.51 %K−1, respectively. This optical thermometry for brazing seam will further promote the joint reliability research and provide new strategies to measure the temperature in micro-region of component.

Fabrication, physical characteristic, and gamma-photon attenuation parameters of newly developed molybdenum reinforced bismuth borate glasses

To observe the direct effect of molybdenum reinforcement on nuclear radiation shielding properties, a detailed investigation was performed with a group of bismuth borate glasses. Accordingly, glass samples with the nominal compositions (65-x)B2O3 + 20Bi2O3 + 15Na2O + xMoO3: x = 0, 1.5, 3, 4.5, 6 and 7.5 wt% have been synthesized by the solid state conventional method. The samples were named as M0 (x = 0), M1 (x = 1.5), M2 (x = 3), M3 (x = 4.5), M4 (x = 6) and M5 (x = 7.5). Physical characteristics and gamma-photon attenuation properties of (M0-M5) glasses have been investigated via MCNPX simulation code and XCOM program. XRD patterns confirmed that M0-M5 glasses were in amorphous nature. The density of the prepared glasses increased from 4.4104 for M0 glass sample to 5.3012 gm cm−3, while molar volume decreased from 33.50083 to 28.92114 cm3 mol−1. The mass attenuation coefficient (μm) increased with the increment of MoO3 concentration in mol% and followed the order: (M0)μm < (M1)μm < (M2)μm < (M3)μm < (M4)μm < (M5)μm at all photon energies. The mean free path (MFP), half value layer (HVL), and tenth value layer (TVL) for the prepared glasses M0-M5 have the same trend and follow the order: (M5)MFP, HVL, TVL < (M4) MFP, HVL, TVL < (M3) MFP, HVL, TVL < (M2) MFP, HVL, TVL < (M1) MFP, HVL, TVL < (M1) MFP, HVL, TVL. The M5 glass sample (with maximum MoO3) achieved highest effective atomic number (Zeff)and equivalent atomic numbers (Zeq) values for all photon energy ranges (low-medium-high). Among all the glass samples, the exposure build-up factor (EBF) and energy absorption build-up factor (EABF) values for M5 glass sample with the highest MoO3 additive are minimum due to the low amount of photons accumulated. These results indicate that M5 glass sample theoretically provides maximum protection for gamma-rays among all the samples.

Structural investigation of Bi2O3-P2O5-B2O3-V2O5 quaternary glass system by Raman, FTIR and thermal analysis

A new kind of bismuth borate glasses based on P2O5-V2O5-Bi2O3-B2O3 system is prepared by the modified melt-quenching method. The conformation of the amorphous phase in the sample was done through X-ray diffraction analysis. The density, molar volume, oxygen molar volume and oxygen packing density in the glass network were investigated according to the substitution of Bi2O3 by B2O3. The density and the molar volume decreased in parallel with B2O3 content increase. Simultaneously, oxygen molar volume values decreased while the oxygen packing density values increased. It is found that B2O3 is the component that contributes most to increase the thermal stability of the glasses, while Bi2O3 is the most contributing oxide to decrease the thermal stability. The structural origins for the variations of the thermal stability with the glass composition are discussed based on the Fourier-transform infrared (FTIR) spectrometry measurement FTIR spectroscopy reveals that the incorporation of V2O5 in the glass network helps to convert the structural units of [BO3] into [BO4].

Structural and Mechanical Properties of Lithium Bismuth Borate Glasses Containing Molybdenum (LBBM) Together with their Glass–Ceramics

This study reports that MoO3 doped glasses (LBB) are produced by a melting traditional process and using the XRD diffractometer technique to check their states. FTIR spectral analysis has examined the functional groups of the glass matrix. FT-IR spectrums reveal that the BO3, BO4. BiO6 and MoO6 octahedral have been built up and structural unit BO3 was transformed into BO4. The mechanical characteristics were linked to the FT-IR spectrum results. Ultrasonic velocities, elastic modulus, density, and thermal stability increased, while molar volume decreased. The increase in these parameters is linked with [BO4] the formation of structural units, an increase the strength of Mo – O, and force constant is higher than Li – O, so glass rigidity increases. Therefore, the increase of MoO3 usually has a significant influence on the bridging oxygen (BO) formation in BBL glasses. The increase in thermal stability connected to an increase in average force constantly, and the replacement of Li–iO with Mo–O linkages. The bond dissociation energy of Li–Li (137.3 ± 6.3 kJ/mol) is much weaker than the dissociation energy of Mo–Mo (449 ± 1 kJ/mol). Lithium borate Li2B4O7 (diomignite) has been identified in all formed glass–ceramics. With the increasing MoO3, the intensity of diomignite diffraction peaks (Li2B4O7) was reduced and transformed into a less stable lithium borate (Li2B2O5) phase.

Spectroscopic and dilatometric analysis of low-melting bismuth borate glasses in the Bi2O3–BaO–Li2O–B2O3 quaternary

Bismuth borate glasses with (25 + x)Bi2O3–15BaO–10Li2O-(50 – x)B2O3 (where x = 0, 10, 20, 30 in mol%) compositions have been prepared by the standard melting technique, and characterized by X-ray diffraction (XRD), UV/Vis optical absorption (OA), thermal/dilatometric analysis, Fourier transform-infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The XRD data confirmed the amorphous nature of the glasses in the 25–55 mol% Bi2O3 range, while the OA evaluation revealed a red shift in the glass absorption edge. A decrease in the optical band gap energies with increasing bismuth content was indicated by a Tauc plot assessment of the OA data. The thermal characterization showed that the coefficient of thermal expansion increased with bismuth oxide concentration, whereas the glass transition and softening temperatures decreased. However, these trends were not monotonic, but showed a tendency to plateau. The analyses by FT-IR and XPS (O 1s) pointed to structural rearrangements induced by the higher Bi2O3/B2O3 ratios, basically concurring with the evolution of BO3 units toward BO4 tetrahedra and the increase in non-bridging oxygens in the glasses. The evolution of the thermal properties was ultimately indicated to be linked with the structural changes.