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The techniques of melt-quenching have been used to generate 53B 2 O 3 —2NaF—27PbO – ( 20 - x ) BaO— x La 2 O 3 ( 0 ≤ x ≥ 15 ) g l a s s s y s t e m . XRD patterns have been established the amorphous character of glass samples. There is a clear evidence of the role of the La 2 O 3 modifier in the glass network. The thermal characteristics have been identified to increase with an increase in La 2 O 3 content. Increasing La 2 O 3 increases the linear and non-linear optical bandgap energy and the Urbach energy. By adding La 2 O 3 to the glass samples, the refractive index, molar polarizability, polarizability, and optical basicity increased. The bulk modulus and the glass transition temperature increased because of the increase in bond strength. The number of bonds per unit increased with the increase in La 2 O 3 content because of the modifier character of La 2 O 3 in the glass samples. Many optical parameters ( ε ∞ ), ( ε o ), χ ( 1 ) , χ ( 3 ) and ( n 2 ) as a function of linear and non-linear E opt have been obtained. The extent of shielding in this article has been examined with the increment in La 2 O 3  at the expense of BaO. The results correspond with similar studies conducted before.

A glass system of composition 3As2O3-37PbO-(60-x) P2O5-xWO3 (0≤x≤ 5 mol%) was synthesized using a conventional melt-quenching method. The characteristics of the optical properties were studied in detail by measuring the absorbance and transmittance spectra of the synthesized glass. The indirect optical band gap decreased from 4.55 eV to 4.33 eV, while the direct band gap decreased from 4.88 eV to 4.76 eV. The Urbach energy varied between 0.55 eV and 0.42 eV. The results obtained for the optical energy band gap and the refractive index demonstrated a slight increase with an increase in tungsten ions in the prepared samples. Basicity, electronegativity, polarizability, metallization, and physical characteristics were estimated based on the obtained results. The refractive index and optical band gap were estimated theoretically by determining the optical basicity and molar refractivity. The half-value layer (HVL) and mean free path (MFP) were estimated and were found to decrease with an increase in tungstate ions in the fabricated glasses. The electron number density (Neff) and effective conductivity (Ceff) were determined as follows: (Neff, Ceff)W0% < (Neff, Ceff)W1% < (Neff, Ceff)W2% < (Neff, Ceff)W3% < (Neff, Ceff)W5%. Our findings confirmed that the PPA glass containing W ions could provide a superior material for use as a gamma attenuation shield.

A new method (named as DASF: Derivation of absorption spectrum fitting) is proposed for the determination of optical band gap and the nature of optical transitions in semiconductors; this method only requires the measurement of the absorbance spectrum of the sample, avoiding any needs to film thickness or any other parameters. In this approach, starting from absorption spectrum fitting (ASF) procedure and by the first derivation of the absorbance spectrum, the optical band gap and then the type of optical transition can be determined without any presumption about the nature of transition. DASF method was employed on (60−x)V 2 O 5 –40TeO 2 –xAg 2 O glassy systems (hereafter named as TVAgx), in order to confirm the validity of this new method. For the present glasses, the DASF results were compared with the results of ASF procedure for, confirming a very good agreement between these approaches. These glasses were prepared by using the melt quenching and blowing methods to obtain bulk and film samples, respectively. Results show that the optical band gap variation for TVAgx glasses can be divided into two regions, 0 ≤  x  ≤ 20 and 20 ≤  x  ≤ 40 mol%. The optical band gap has a maximum value equal to 2.72 eV for x  = 40 and the minimum value equal to 2.19 eV for x  = 40. Also, some physical quantities such as the width of the band tails (Urbach energy), glass density, molar volume, and optical basicity were reported for the under studied glasses.

A new model describing zircon saturation in silicate melts is presented that combines the results of 196 data from new experiments with data from previous experimental studies. In the new experiments, the concentration of Zr in melts coexisting with zircon was determined at temperatures between 800 and 1500 °C for 21 compositions (with alumina saturation index, ASI, from 0.20 to 1.15), containing ~ 1 to 16 wt % FeO T and, for a subset of these conditions, at variable pressure (0.0001 to 4.0 GPa) and water content (0 to 15 wt %). The collated dataset contains 626 data, with 430 from 26 literature studies, and covers conditions from 750 to 1620 °C, (including 45 new data and 106 literature data for temperatures < 1000 °C), ASI 0.20 to 2.00, 0.0001 to 4.0 GPa and 0 to 17 wt % H 2 O. A limitation of previous models of zircon saturation is the choice of parameter used to describe the silicate melt, which may not be appropriate for all compositions and can result in differences in predicted temperatures of over 200 °C for granitic systems. Here we use optical basicity ( Λ ), which can be easily calculated from the major oxide components of a melt, to parameterise the composition. Using a non-linear least-squares multiple regression, the new zircon saturation model is: log Zr = 0.96 ( 5 ) - 5790 ( 95 ) / T - 1.28 ( 8 ) P + 12.39 ( 35 ) Λ + 0.83 ( 9 ) x . H 2 O + 2.06 ( 16 ) P Λ where Zr is in ppm, T is temperature in K, P is pressure in GPa, Λ is the optical basicity of the melt, x .H 2 O is the mole fraction of water in the melt, and the errors are 1σ. This model confirms that temperature and melt composition are the dominant controls on zircon solubility. In addition, pressure and melt water content exert small but resolvable effects on the solubility and are included, for the first time, in a model. Using this new calibration, 92% of the predicted temperatures are within 10% of the experimental temperatures for the collated dataset (with an average temperature difference of 57 °C), while predicted temperatures for only 78 and 62% of the collated dataset are within 10% of the experimental temperature (with average temperature differences > 80 °C) using the widely cited Watson and Harrison (Earth Planet Sci Lett 64:295–304, 1983) and Boehnke et al. (Chem Geol 351:324–334, 2013) models, respectively. This new model can be extrapolated to temperatures below those included in the calibration with greater accuracy and when applied to melt inclusions from the Bishop Tuff, gives temperatures that are in excellent agreement with independent estimates.

In this present work we have studied the physical, structural, thermal, and optical properties of a new set of alkali zinc boro tellurite glasses doped europium trioxide prepared using the melt-quenching method. X-ray diffraction technique (XRD) and SEM were used to determine the non-crystalline property and microstructure property of the prepared samples. By using MAS-NMR spectroscopy and FTIR spectroscopy, the structural changes in the glasses were revealed. The physical properties were described by considering the densities of glass samples and hence molar volume, polaron radius, and oxygen packing density were measured. Thermal stability of glasses was perceived by performing DSC analysis and values ranges from 145 to 190 °C. Using UV–visible absorption spectra, it was possible to calculate the optical properties. The highest refractive index is found as 2.275 for glass AZBTE0 and the lowest is 2.241 for AZBTE5 glass. The ionic behaviour of the glasses was determined by electronegativity and values lie in the range of 1.51 to 1.688. The outcomes of the physical, thermal, and optical characteristics of glasses are intended for potential uses in optical switching and Europium doped fibre amplifier applications.

Five new strontium barium borate (BNBD) glasses doped with dysprosium ion and different concentrations of niobium pentoxide were synthesized using the standard melt-quenching method. The physical, structural, optical and gamma radiation shielding properties of these glasses were investigated. Density, average molecular weight, refractive index, molar volume, optical dielectric constant, boron-boron separation, metallization criterion, oxygen packing density, Poisson ratio, optical basicity, optical electronegativity, and two-photon absorption coefficients of the synthesized glasses were determined. By the addition of Nb 2 O 5 content, boron-boron distance and oxygen packing density values increased, while molar volume of oxygen decreased due to the formation of bridging oxygen. The two-photon absorption could be constrained by replacing BaCO 3 by niobium pentoxide content which further influences the bandgap. The ionic nature of the titled glasses is discussed using the bonding parameter, optical basicity, ionic and covalent characteristic parameter values. Moreover, the shielding ability of dysprosium ions doped niobium borate glasses against photons, fast neutrons and electrons has been extensively evaluated. For this purpose, the mass attenuation coefficient (µ/ρ, cm 2 /g) of the glasses and several photon protection parameters, derived from µ/ρ were obtained for 0.015–15 meV. The maximum µ/ρ values were achieved for BNBD0 glass, varying between 0.033 and 35.430 cm 2 /g. The lowest buildup factor values were found for BNBD0 glass. Furthermore, effective removal cross section values for fast neutrons increased steadily between 0.125 and 0.130 cm −1 due to the increase in the density of the glasses with the enhancing of Nb 2 O 5 concentration. It was noticed that the range of high energy electrons was shorter on the BNBD0 glass. It was concluded that BNBD0 glass with high BaCO 3 concentration can be considered as an alternative material in nuclear radiation shielding applications.

Glasses having the stoichiometry ratio [(70-x) B 2 O 3 –10Na 2 O–20ZnO–xNiO] where 0.0 ≤ x < 0.3 mol% were synthesized using a melt quenching technique. The X-ray diffraction (XRD) technique confirmed the non-crystalline properties of the glasses. Surface morphology and elemental analysis were done by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) spectra. The glass density ranged from 2.539 to 2.597 gcm −3 and the physical characteristics such as ion concentration, inter-ionic distance, average boron-boron distance, oxygen packing density, polaron radius, and field strength were calculated and interpreted. The deconvolution spectra of Fourier Transfer Infra-Red (FTIR) and Raman spectroscopy resulted in BO 3 unit to BO 4 unit conversion as the NiO concentration increased. The UV–Visible spectroscopy showed absorption peaks near 425 nm and 800 nm corresponding to 3 A 2g (F) →  3 T 1g (P)) and ( 3 A 2g (F) →  1 E g ( 3 F)) transitions respectively. The direct bandgap decreased from 4.00 to 3.76 eV, but the indirect bandgap increased from 3.00 to 3.12 eV. The Urbach energy of glasses decreased from 0.56 to 0.35 with an increase in NiO concentration showing the compactness of the glass network. Furthermore, optical characteristics were determined, including the refractive index, dielectric constant, metallization criterion, electronic oxide ion polarizability, optical basicity, and numerical aperture. Photoluminescence spectra exhibit strong green and cyan emission due to d-d transitions of Ni 2+ . The CIE Chromaticity coordinates confirm that the observed green light emission from BZNNi glasses are suitable candidates for optoelectronic applications.

Novel Li 2 O–ZnO–SiO 2 –P 2 O 5 glasses doped with Nd 2 O 3 have been prepared via the ordinary melt-quenching technique. Density and molar volume, FTIR spectra, and UV–visible absorption spectroscopy were used to investigate the physical, structural, and optical properties of glasses. The density increases from 2.545 to 2.644 g.cm −3 and the molar volume decreases from 38.158 to 37.794 cm 3  mol −1 . The values of the optical gap energies of the samples increased from 3.331 to 3.712 eV with the addition of Nd 3+ ions. The results of the infrared spectra analysis showed many vibration modes, and it was found that the intensity of both P–O − and Si–O − vibration modes decreases with the increase in Nd 3+ ions, which confirms the increase in the bridging oxygen (BO). The theoretical optical basicity ( Λ th. ) values increased from 1.205 to 1.238, while the interaction ( A ) values decreased from 0.2209 to 0.2189 Å 3 . The nuclear radiation shielding parameters, such as mass attenuation coefficient, mean free path, half-value layer, effective atomic number, and electron density, were estimated using Phy-X/PSD and XCOM software programs. The effect of Nd 2 O 3 content on radiation protection properties was evaluated. The results showed that the LiZnSiP:4Nd glass sample gave the best protection against gamma and neutron radiation.

The Nd 3+ -doped lithium–zinc–phosphate glasses were prepared by means of conventional melt quenching method. X-ray diffraction results confirmed the glassy nature of the studied glasses. The physical parameters such as the density, molar volume, ion concentration, polaron radius, inter-ionic distance, field strength and oxygen packing density were calculated using different formulae. The transmittance and reflectance spectra of glasses were recorded in the wavelength range 190–1200 nm. The values of optical band gap and Urbach energy were determined based on Mott–Davis model. The refractive indices for the studied glasses were evaluated from optical band gap values using different methods. The average electronic polarizability of the oxide ions, optical basicity and an interaction parameter were investigated from the calculated values of the refractive index and the optical band gap for the studied glasses. The variations in the different physical and optical properties of glasses with Nd 2 O 3 content were discussed in terms of different parameters such as non-bridging oxygen and different concentrations of Nd cation in glass system.

Barium titanium borate glasses doped with ytterbium ions were fabricated via standard melt quenching technique. The building structure of the glass matrices doped with ascendant ratios of ytterbium ions were studied using Raman and FTIR spectroscopies. The UV–Vis–NIR optical absorption spectra were investigated and used to calculate optical bandgaps, Urbach energies, refractive indices, metallization criterion, optical basicity, and dispersion parameters. The absorption and emission cross-sections and gain spectra for 2 F 5/2  →  2 F 7/2 transition of ytterbium ions were investigated. The high values of the emission cross-sections of the studied glasses make them strong candidates for laser and amplifier applications.