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Base and glass samples with nominal compositions 65B2O3-15NaF-15ZnO-5Bi2O3-0.25CoO-XLa2O3 with X = 0.0–0.6 mol% were produced using the melt quenching technique. The nature of the samples, and the physical, FTIR, and dielectric characteristics were investigated. The XRD data confirmed the non-crystalline state of samples. The density (Ds) of the base and La-X glasses was varied from 3.10 g cm−3 to 3.42 g cm−3. The molar volume (Vm) was decreased from 28.05 cm3/mol to 26.46 cm3/mol. Values of the oxygen molar volume (OMV) declined from 12.47 cm3/mol to 11.83 cm3/mol. The oxygen packing density (OPD) increased from 80.20 g atm l−1 to 84.52 g atm l−1. The FTIR measurements confirmed that incorporation of CoO and La2O3 caused an increased conversion of BO3 to BO4, which caused NBOs to decline and vanish throughout this process. All the glasses under consideration, which were loaded with various quantities of lanthanum (La2O3) and a constant amount of cobalt (CoO), showed a considerable decrease in dielectric constant (ε′) as the frequency rose throughout the low-frequency band. The ε′ decreased dramatically with the addition of CoO. Then, it decreased more when La2O3 was added, achieving 0.4 mol% at the constant amount of CoO. Among the examined samples, the glass sample (La-0.4) loaded with 0.25 mol% of CoO and 0.4 mol% of La2O3 is thought to be promising material for electronic packaging since it has the fastest transmission speed and the lowest dielectric constant. [ABSTRACT FROM AUTHOR]

The effect of vanadium oxide (V2O5) on the structural, dielectric, and shielding features of borate-lead-fluoride glasses was investigated. The density of the glass network increased steadily from 3.18 to 3.28 g.cm−3 as the vanadium content increased from 0.0 to 10 mol%. The evolution of functional groups and units such as non-bridging BO3, and bridging BO4, in our newly developed glasses was exposed by FTIR analysis. Since the fraction of bridging units BO4 increases when V2O5 is added up to 2 mol%. This indicates that the conversion of BO3 groups into BO4 groups is facilitated by V2O5. However, at higher concentrations of V2O5 (> 2 mol%), a reversal reaction occurs wherein the BO3 unit fraction increases and the BO4 unit fraction starts to decrease. All the glasses loaded with different amounts of V2O5 mol% had a sharp decline in dielectric constant with increasing frequency over the low frequency interval. As the V2O5 level grew up to 2 mol%, the dielectric constant value was marginally reduced and then increased for higher concentrations. All of the glasses under examination displayed different relaxation peaks in the range of 100 Hz to 20 kHz on their measured loss tangent (tan δ), but vanadium doping caused them to shift to higher frequencies. At 0.015 MeV, the maximum MAC values for the V-0.0 to V-10.0 samples were found to be 29.205 cm2/g to 30.082 cm2/g. In terms of radiation shielding, the V-10.0 sample exhibited the highest values of mass (MAC) and linear (LAC) attenuation coefficients, while the same sample possessed the lowest values of half value layer and mean free path among all investigated glasses. Therefore, the investigate glass can be used in several optical and radiation shielding applications. [ABSTRACT FROM AUTHOR]

The role of the [Na2O]/[CuO] ratio in two glass groups with a chemical formula of (50 − y/2)Na2O–yCuO–(50 − y/2) P2O5 (y = 0.0–40 mol%) coded as Line I and (50 − y)Na2O–yCuO–50P2O5 (y = 0.0–50 mol%) coded as Line II on physical and gamma-ray attenuation properties have been deeply investigated. The density (ρ) varied from 2.471 to 3.262 g/cm3 and from 2.471 to 3.113 g/cm3 for Line I and Line II glasses, respectively. The molar volume (Vm) values varied from 41.280 to 28.526 cm3/mol and from 41.280 to 35.609 cm3/mol for Line I and Line II glasses, respectively. The oxygen molar volume (OMV) reduced from 13.761 to12.972 cm3/mol and from 13.761 to 11.873 cm3/mol, while the oxygen packing density (OPD) improved from 72.674 to 77.124 and from 72.674 to 84.253 g.atom/l for Line I and Line II glasses. The mass and linear attenuation coefficients (MAC and LAC) values corresponding to the Line II glass is slightly lower than their counterpart of the Line I. The effective atomic numbers (Zeff) and electron density (Neff) for glasses in Line I was lower than that for those in Line II. Exposure (EBF) and energy absorption (EABF) buildup factors have the same trend in both glass groups. The findings support the capability to utilize the examined glasses as radiation shielding materials. [ABSTRACT FROM AUTHOR]