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Theoretical prediction of glass compositions with certain performance requirements is a long‐standing challenge in glass research. The difficulty lies in revealing the relationship of glass's composition–structure–property (C–S–P), and establishing a predictive calculation method for glass properties with high accuracy. Here we determine quantitatively the C–S–P relationships of four silicate laser glasses using nearest‐neighboring congruently melting compounds (CMCs) as “component and structural motifs”. For all studied silicate systems, physical properties such as density and refractive index are predicted with an error of less than 5%. Spectroscopic properties, including Judd–Ofelt parameters, fluorescence branching ratio (β), effective bandwidth (Δλeff), emission cross‐section (σe), gain bandwidth, and lifetime, are predicted with an error of less than 10%, with some properties such as β, Δλeff, and σe showing an error of less than 5% in specific systems. Four C–S–P databases have also been constructed, containing detailed physical and spectroscopic properties of over 1200 compositions, facilitating the optimization of glass composition. These findings highlight the significance of nearest‐neighboring CMCs in understanding and developing high‐performance laser glasses. [ABSTRACT FROM AUTHOR]

Sulfur (S) in the mantle is conventionally assumed to be exclusively stored in accessory sulfide phases, but recent work shows that the major silicate minerals that comprise >99% of the mantle could be capable of hosting trace amounts of S. Assessing the incorporation of trace S in nominally S-free mantle minerals and determining equilibrium S partitioning between these minerals and basaltic melt requires analyzing small experimental phases with low S contents. Here, we develop a protocol for EPMA analysis of the trace levels of S in silicate phases. We use a suite of natural and experimental basaltic glass primary and secondary standards with S contents ranging from 44 ppm to 1.5 wt%. The effects of beam current and counting time are assessed by applying currents ranging from 50 to 200 nA and total counting times between 200 and 300 s at 15 kV accelerating voltage. We find that the combination of 200 nA beam current with a 200 s counting time (80 s peak, 60 s each for upper and lower background, respectively) achieves precise yet cost-effective measurements of S down to a calculated detection limit of ~5 ppm and a blank-derived, effective detection limit of ~17 ppm. Close monitoring of the S peak intensity and position throughout the duration of each spot also shows that high currents and extended dwell times do not compromise the accuracy of measurements, and even low S contents of 44 ppm can be reproduced to within one standard deviation. Using our developed recipe, we analyzed a small suite of experimental clinopyroxenes (Cpx) and garnets (Gt) from assemblages of silicate partial melt + Cpx ± Gt ± sulfide, generated at 1.5 to 3.0 GPa and 1200 to 1300 °C. We find S contents of up to 71 ± 35 ppm in Cpx and 63 ± 28 ppm in Gt and calculate mineral-melt partition coefficients ( (D s min/melt) ) of up to 0.095 ± 0.064 and 0.110 ± 0.064 for D s Cpx/melt and D s Gt/melt , respectively. The sulfur capacity and mineral-partitioning for Cpx are in good agreement with SXRF measurements in a prior study by Callegaro et al. (2020), serving as an independent validation of our EPMA analytical protocol. [ABSTRACT FROM AUTHOR]

The paper presents the results of developing Er-doped optical fibers for creating random single-frequency lasers in the wavelength range of 1570–1610 nm. The possibility of broadening the luminescence band of Er3+ ions in silicate glasses in the long-wavelength region of the spectrum by introducing a high concentration of P2O5, as well as by additional doping with Sb2O3, is investigated. It is found that both approaches do not improve the dynamics of luminescence decay in the L-band. In addition, Er2O3-GeO2-Al2O3-SiO2 and Er2O3-GeO2-Al2O3-P2O5-SiO2 glasses were studied as the core material for L-band optical fibers. The developed fibers exhibited high photosensitivity and a high gain of 5 and 7.2 dB/m, respectively. In these fibers, homogeneous arrays of extended weakly reflecting Bragg gratings were recorded directly during the fiber drawing process. Samples of arrays 5 m long and with a narrow reflection maximum at ~1590 nm were used as the base for laser resonators. Narrow-band random laser generation in the wavelength region of 1590 nm was recorded for the first time. At a temperature of 295 K, the laser mode was strictly continuous wave and stable in terms of output power. The maximal power exceeded 16 mW with an efficiency of 16%. [ABSTRACT FROM AUTHOR]

Abstract A successful attempt to produce a multi-function glass shield for attenuating neutrons and gamma rays by reinforcing a silicate glass network with boron and bismuth has been accomplished. A composition of 20SiO2-80Na2O (BSiBi0) was proposed to be used as a host glass network and prepared using the melt/annealing techniques. The low concentration of SiO2 in BSiBi0 was not sufficient to form a stable glass network. Then, the proposed BSiBi0 was modified with 10, 20, 30, and 40 mol% of each of B2O3 and Bi2O3 (BSiBi1, BSiBi2, BSiBi3, and BSiBi4) simultaneously. The structural effects of adding B3+ and Bi3+ were studied through X-ray diffraction, density, and FTIR, which all showed enhancement of glass forming ability, a former role of Bi3+ ions, and crowded the glass network by BO4 units. The derived structural parameters $$-$$ - molar volume, mean silicon – silicon separation, mean boron – boron separation, oxygen packing density, packing density, and number of bridging/non-bridging oxygen $$-$$ - were extensively discussed to explore the impact of B3+ and Bi3+ on the formed network. The richness of the proposed host glass network by B3+ and Bi3+ enhanced its thermal stability. The obtained elastic properties by ultrasonic measurements reflect the increase of the glass rigidity with increasing concentrations of B3+ and Bi3+ ions. The obtained glasses have high visible light transparency and almost complete UV absorption. The measured shielding parameters against two types of neutron energies (total slow and slow) and a wide range of gamma rays’ energies showed a significant improvement in the shielding efficiency of the considered glasses. The total slow neutrons, slow neutrons, and gamma rays’ attenuation abilities were improved by 22.9, 135.5, and 73.8 $$-$$ - 199.5%. High thermal stability, elasticity, visible light transparency, and neutrons and gamma rays’ attenuation performance features give the produced glasses, especially BSiBi4 glass, preference as shielding materials in nuclear fields.

The present work studies the effect of CeO2 additions on the structure, properties, and shielding ability against radiation of the 30CaO–20MgO–5P2O5–45SiO2 (mol%) glass system. Five glass samples, depending on the CeO2 doping of 0.5, 1.5, 3, and 5 g on a 100% glass batch, prepared through the conventional melting process. The glasses examined using XRD, DTA, and FTIR spectroscopies with measurements of density (ρ), molar volume (Vm), and crystalline volume (Vc). Different effective radiation shielding parameters also computed via Phy-X/PSD software. The amorphous character is dominant in all tested samples. As well, CeO2 additions increase the values of ρ, Vm, and Vc. The sample coded as GCe5 (doped with 5 g of CeO2) possessed the highest values of the mass-absorption coefficient (MAC) and the sample GCe0 (free with CeO2) possessed the lowest values. The linear-absorption coefficient (LAC) parameter has the same trend of MAC. Therefore, (MAC and LAC)GCe0 < (MAC and LAC)GCe0.5 < (MAC and LAC)GCe1.5 < (MAC and LAC)GCe3 < (MAC and LAC)GCe5. Half value layers (HVLs) for the investigated glasses have an opposite trend as CeO2 increasing in the glass networks. Thus, (HVL)GCe0 > (HVL)GCe0.5 > (HVL)GCe1.5 > (HVL)GCe3 > (HVL)GCe5. Both effective atomic number (Zeff) and effective conductivity (Ceff) parameters have the same trend of MAC and LAC. Results confirmed that the investigated glasses are superior as γ-ray shields compared to some commercial concrete. Therefore, CeO2 was found in the silicate glass network as a former oxide in tetrahedral units (CeO4) and increased the bridging bonds in place of NBO in the glass network, which led to a significant increase in the γ-ray shielding properties around silicate atoms. [ABSTRACT FROM AUTHOR]

A successful attempt to produce a multi-function glass shield for attenuating neutrons and gamma rays by reinforcing a silicate glass network with boron and bismuth has been accomplished. A composition of 20SiO2-80Na2O (BSiBi0) was proposed to be used as a host glass network and prepared using the melt/annealing techniques. The low concentration of SiO2 in BSiBi0 was not sufficient to form a stable glass network. Then, the proposed BSiBi0 was modified with 10, 20, 30, and 40 mol% of each of B2O3 and Bi2O3 (BSiBi1, BSiBi2, BSiBi3, and BSiBi4) simultaneously. The structural effects of adding B3+ and Bi3+ were studied through X-ray diffraction, density, and FTIR, which all showed enhancement of glass forming ability, a former role of Bi3+ ions, and crowded the glass network by BO4 units. The derived structural parameters - molar volume, mean silicon – silicon separation, mean boron – boron separation, oxygen packing density, packing density, and number of bridging/non-bridging oxygen - were extensively discussed to explore the impact of B3+ and Bi3+ on the formed network. The richness of the proposed host glass network by B3+ and Bi3+ enhanced its thermal stability. The obtained elastic properties by ultrasonic measurements reflect the increase of the glass rigidity with increasing concentrations of B3+ and Bi3+ ions. The obtained glasses have high visible light transparency and almost complete UV absorption. The measured shielding parameters against two types of neutron energies (total slow and slow) and a wide range of gamma rays' energies showed a significant improvement in the shielding efficiency of the considered glasses. The total slow neutrons, slow neutrons, and gamma rays' attenuation abilities were improved by 22.9, 135.5, and 73.8 - 199.5%. High thermal stability, elasticity, visible light transparency, and neutrons and gamma rays' attenuation performance features give the produced glasses, especially BSiBi4 glass, preference as shielding materials in nuclear fields. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are performed to investigate the structural response of titania silicate glass to temperature. The coefficient of thermal expansion is computed for two titania silicate glasses with 0 and 10 mol% titania content, the structures of which are presented in terms of radial and angular distributions. Revealed by the different changing rates of intertetrahedra bond angles and bond lengths with respect to the Ti and Si atoms, the glass structures tend to exhibit a nonvectorized expansion process at elevated temperatures, leading to inconsistent expansion rates of the structures in different scales. While the average length of TiO and Si‐O bonds both increases with temperature, the decrease in the coefficient of thermal expansion by the addition of Ti atoms is associated with the different expansion rate of tetrahedra. Arising from the gradual decrease in atomic overlapping, decrease in free volume inside the glass with temperature is also identified. [ABSTRACT FROM AUTHOR]

This study highlights the influence of replacing Na2O with NaF on the photon interaction parameters of 40SiO2-20Al2O3-(10 + x)Na2O-(20-x)NaF-10YF3 (for x = 0, 2, 5, 7, 10). The mass attenuation coefficients (MACs) and mass energy absorption coefficients (MEACs) of the glass ceramics were computed for gamma-rays in the 15 keV-15MeV energy range using the NIST-XCOM database. The MAC and MAEC vary within the ranges of 0.0224–10.1508 cm2/g and 0.0156–6.4896 cm2/g for Si-ANNYF1, 0.0223–9.8821 cm2/g and 0.0164–6.3694 cm2/g for Si-ANNYF2, 0.0222–9.6097 cm2/g and 0.0163–6.2508 cm2/g for Si-ANNYF3, 0.0221–9.3724 cm2/g and 0.0163–5.5476 cm2/g for Si-ANNYF4, and 0.0220–9.1310 cm2/g and 0.0162–5.4131 cm2/g for Si-ANNYF5. The analysis of other estimated parameters showed that increasing the relative weight proportion of NaF2 relative to Na2O influenced the ability of the glass ceramics to interact and absorb energy from incident gamma photons. Adding more NaF made the glass ceramics better at confining photons in both the narrow and broad beams scenarios. The Si-ANNYFx glass ceramics are recommended for gamma shielding applications in nuclear industries. [ABSTRACT FROM AUTHOR]

In recent years, the scientific community has spent significant effort exploring radiation-shielding glass materials. The present work was conducted by synthesizing a glass series of 20La2O–10BaO –15Na2O–(55−x)SiO2–xBi2O3, x: 0, 5, 15, and 25 wt%. After producing the samples, in-depth studies were performed on the physical, optical, thermal, and radiation attenuation properties of the fabricated glass series. A radical color change from nearly neutral to dark-brown color occurred as Bi2O3 entered the glass network. The density values equaled 2.8324, 2.9511, 3.0992, and 3.3657 g cm−3 for LBSS1 to LBSS4 samples, respectively. According to XRD patterns, neither sharp nor moderate peaks developed; a hump-like formation between 20 and 35 degrees was visible in all glass samples. FTIR measurement revealed transmission as a function of varying wavenumber from 4000 to 400 cm−1 for the prepared glass specimens, and different bond types were noted. The UV–Vis technique removes it displayed that increasing Bi2O3 content blocked light transmission throughout the glass medium. The radiation-shielding parameters of linear attenuation coefficient (LAC), mass attenuation coefficient, transmission factor, and half value layer were calculated with experimental and MC simulation methods for all glass samples at six different energies between 356 and 1332 keV. The results were compared with the Phy-X database, and good agreement was obtained. The highest LACs were obtained at the lowest energy (356 keV) with values of 0.3108, 0.3455, 0.4471, and 0.5486 cm−1 for LBSS1, LBSS2, LBSS3, and LBSS4 glasses, respectively. The photon attenuation ability of the LBSS glasses increased by increasing the Bi2O3 ratio, especially at low energies. Therefore, the authors can conclude that future applications, such as observation window in CT rooms, may efficiently exploit LBBS4 glass system. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) glass-converted light-emitting diodes (gc-LEDs) are newly emergent broadband light sources for miniaturizing optical systems like spectrometers. While lots of effort has been spent on materials doped with rare-earth and transition-metal ions, the achievement of these materials with broadband NIR emission and desired wavelength region remains a long-standing challenge, especially operating in the spectral region between 700 and 1100 nm. Herein, a broadband NIR LEDs based on Te cluster-doped silicate glass is developed. Through adjustment of melting atmosphere and network topology of the glass matrix, active NIR Te cluster centers can be generated and stabilized in silicate glass and show a broad emission at 980 nm with a full width at half maximum (FWHM) of 300 nm under blue light excitation. The photoluminescence of the glass matches well with the absorption of several primary chemical bonds in food and biological tissue. In demonstration experiments, the NIR absorption of different biological tissue by NIR light from our glass is measured, suggesting that the super-broad NIR luminescence of Te-doped silicate glass has potential applications as light sources for nondestructive analysis. [ABSTRACT FROM AUTHOR]

The paper presents the results of developing Er-doped optical fibers for creating random single-frequency lasers in the wavelength range of 1570–1610 nm. The possibility of broadening the luminescence band of Er3+ ions in silicate glasses in the long-wavelength region of the spectrum by introducing a high concentration of P2O5, as well as by additional doping with Sb2O3, is investigated. It is found that both approaches do not improve the dynamics of luminescence decay in the L-band. In addition, Er2O3-GeO2-Al2O3-SiO2 and Er2O3-GeO2-Al2O3-P2O5-SiO2 glasses were studied as the core material for L-band optical fibers. The developed fibers exhibited high photosensitivity and a high gain of 5 and 7.2 dB/m, respectively. In these fibers, homogeneous arrays of extended weakly reflecting Bragg gratings were recorded directly during the fiber drawing process. Samples of arrays 5 m long and with a narrow reflection maximum at ~1590 nm were used as the base for laser resonators. Narrow-band random laser generation in the wavelength region of 1590 nm was recorded for the first time. At a temperature of 295 K, the laser mode was strictly continuous wave and stable in terms of output power. The maximal power exceeded 16 mW with an efficiency of 16%.

Here, Raman spectroscopy is used to develop a univariate partial least squares (PLS) calibration capable of quantifying geochemistry in synthetic and natural silicate glass samples. The calibration yields eight oxide-specific models that allow predictions of silicon dioxide (SiO2), sodium oxide (Na2O), potassium oxide (K2O), calcium oxide (CaO), titanium dioxide (TiO2), aluminum oxide (Al2O3), ferrous oxide (FeOT), and magnesium oxide (MgO) (wt%) in glasses spanning a wide range of compositions, while also providing correlation-coefficient matrices that highlight the importance of specific Raman channels in the regression of a particular oxide. The PLS suite is trained on 48 of the 69 total glasses, and tested against 21 validation samples (i.e., held out of training). Trends in root mean square error of calibration (RMSEC), root mean square error of cross-validation (RMSECV), and root mean square error of prediction (RMSEP) model accuracy metrics are investigated to uncover the efficacy of utilizing multivariate analysis for such Raman data and are contextualized against recently produced strategies. The technique yields an average root mean of calibration (∼2.4 wt%), cross-validation (∼ 2.9 wt%), prediction (∼ 2.6 wt%), and normalized variance (∼ 28%). Raman band positional shifts are also mapped against underlying chemical variations; with major influences arising primarily as a function of overall oxidation state and silica concentration: via ferric cation (Fe3+)/ferrous cation (Fe2+) ratios and SiO2 (wt%). The algorithm is further validated preliminarily against a separate external set of 11 natural basaltic glasses to unravel the limitations of the synthetic models on natural samples, and to determine the suitability of "universal" Raman-model applications in scenarios where prior chemical contextualization of the target sample is possible. This study represents the first time Raman spectra of amorphous silicates have been paired with PLS, offering a foundation for future improvements utilizing these systems. [ABSTRACT FROM AUTHOR]

The spectroscopic characteristics of Er-doped lead silicate glasses were investigated with respect to the effects of glass modifiers (Li+, Na+, K+, Mg2+, Ca2+, Sr2+, and Ba2+)with various optical basicities. Using the absorption spectra of the glasses, the Judd--Ofelt parameters of the glasses were calculated and examined, with an emphasis on the glass emission intensity ratio at 1572 nm. The spectra of the samples at low temperatures were examined, and the Stark splitting of Er3+ was investigated. The McCumber method was used to determine the emission cross sections of glasses. The SPM glass exhibited high values of full width at half maximum (51.24 nm) and the emission cross section at 1572 nm (1.908 x 10-21 cm²), with potential applications for guiding component design of 1.5-μm fiber lasers and amplifiers. [ABSTRACT FROM AUTHOR]

The state-of-the-art fractographic guidelines for glasses and fine ceramics, ASTM C1678, are only applicable to limited fracture scenarios. This work outlines a new method to analyze fracture scenarios outside ASTM C1678′s scope. The proposed methodology consists of a two-step process: initially, optical images of the fracture surfaces are obtained, and visual analysis is used to highlight the characteristic fractographic features. Next, the selected features are automatically compared to a baseline set of virtual fracture patterns tailored to any relevant fracture scenarios obtained by numerical phase-field simulations. As validation, scenarios with fractures originating at the glass plates' edges for both sharp and chamfered corners were analyzed. Strength estimates within 6% of experimental results were achieved with the proposed method. In the future, this technique could be implemented to carry out fractographic analysis on brittle components of arbitrary shapes and loadings, hence substantially extending the application range and accuracy of fractographic methods. [ABSTRACT FROM AUTHOR]

Titanium occurs as Ti3+, in addition to the more usual Ti4+, in extraterrestrial materials such as Lunar basalts and chondritic meteorites. The proportion of Ti as Ti3+ was investigated by Ti K-edge X-ray absorption near edge structure (XANES) spectroscopy for five silicate glass compositions quenched from melts equilibrated at 1400 °C, atmospheric pressure, and oxygen fugacities (f O 2) in log units relative to the fayalite-magnetite-quartz (FMQ) buffer from FMQ+3.3 to FMQ-10.2 (+6.6 to −6.9 log units relative to the iron-wüstite, IW, buffer). All spectra could be well fit using a linear combination of the spectra recorded from the most oxidised and reduced samples of the same composition, indicating that the samples only contain two Ti species. Ti3+/ΣTi (where ΣTi = Ti3+ + Ti4+) = 0 for the most oxidised samples but is unknown for the most reduced. Thus, the linear combination fit results were used in a regression model in which Ti3+/ΣTi of the reduced end-member was varied to give Ti3+/ΣTi values of the other samples that best fit the thermodynamically expected dependence of Ti3+/ΣTi on f O 2. The most reduced samples were found to have Ti3+/ΣTi ∼ 0.6. The resulting modified equilibrium constants of the Ti oxidation reaction, log K ', are linearly correlated with the optical basicity (Λ) parameterisation of melt composition, such that as Λ increases, Ti3+/ΣTi decreases, at constant f O 2. This correlation allows Ti3+/ΣTi to be predicted for other compositions and, assuming that the temperature dependence of Ti3+/Ti4+ is parallel to FMQ, a general equation relating Ti3+/Ti4+ to f O 2 was obtained: log(Ti3+/Ti4+) = −0.25ΔFMQ − 0.32(19) − 3.44(32) Λ. This equation was used to predict Ti3+/ΣTi as a function of f O 2 for high-Ti Mare basalt, chondrule (CV and CM), and calcium aluminium inclusion (CAI; Type A and B) compositions. For melts of these compositions Ti3+ = Ti4+ at ∼ FMQ-10.8, −9.5, −9.3, −10.6, and −10.2 (∼IW-7.5, −6.2, −6.0, −7.3, and −6.9), respectively, independent of temperature. [ABSTRACT FROM AUTHOR]

In the present investigation, we examined the efficacy of lithium calcium silicate glasses doped with nickel for various radiation shielding applications. Specifically, we estimated the mass attenuation coefficients (μm) for samples with the composition (11.5–x)CaO-23.5Li2O-(x)NiO-65SiO2 (x = 0, 2.87, 5.75, 8.63, 11.5 mol.%) using Monte Carlo simulation (GEANT4), Phy-X/PSD, and XCOM programs over an energy range of 0.015–15 MeV. The results demonstrate a strong correlation between the extracted μm magnitudes from the simulation and calculation results. Next, we estimated various other parameters, including the linear attenuation coefficients (μ), half-value layer (HVL), tenth-value layer (TVL), mean free path (MFP), effective atomic number (Zeff), fast neutron removal cross sections (ΣR), relative dose distribution (RDD) for gamma rays, energy absorption buildup factors (EABF), and exposure buildup factors (EBF). We also assessed the alpha and beta shielding characteristics of the glass samples by estimating the continuous slowing down approximation range (CSDA) and total stopping power (TSP) magnitudes. Our findings indicate that μm, μ, Zeff, and ΣR magnitudes increased as the ratio of NiO in the samples increased. In contrast, we observed that HVL, TVL, RDD, MFP, EABF, and EBF magnitudes decreased as the NiO ratio increased. A higher percentage of NiO in the samples resulted in the supply of beta and alpha particles with shorter ranges. Overall, we conclude that the lithium calcium silicate glass doped with nickel with an 11.5% NiO percentage is the optimal specimen for obtaining superior photon and charged particle shielding benefits. [ABSTRACT FROM AUTHOR]

The results of the study of the platinum group minerals of the Baimka gold placer cluster, Western Chukotka, Russia, are presented. Platinum group minerals belong to the iridium–platinum and platinum mineralogical-geochemical types with the Late Jurassic cumulative pyroxenite-gabbro complexes as a probable source. Platinum group minerals came to alluvial gold placers primarily from intermediate reservoirs, which is the Volgian volcanic-sedimentary sequence J3v2–3. Rounded silicate glass inclusions are a specific feature of platinum minerals from the Baimka placer cluster. [ABSTRACT FROM AUTHOR]

This paper investigates the optical properties and radiation shielding performance of borosilicate glasses containing chromium trioxide (CrO3) and strontium titanium oxide (SrTiO3). The optical characteristics, including refractive index, absorption coefficient, and transmission behaviour, were thoroughly analysed to gain insights into the transparency and light-carrying capabilities of the glasses. Additionally, the radiation shielding parameters were obtained by utilizing both FLUKA simulation and the XCOM program. The obtained radiation shielding data were then compared and discussed to assess the effectiveness of the glass compositions as shielding materials against ionizing radiation. The results provide a comprehensive understanding of the optical properties and radiation shielding capabilities of the studied glasses, contributing to the development of novel and efficient materials for radiation protection in various applications, including nuclear medicine, industrial radiography, and space exploration. The findings presented in this study offer valuable information for the design and optimization of borosilicate glasses containing CrO3 and SrTiO3 for effective radiation shielding in neutron-rich environments. [ABSTRACT FROM AUTHOR]

This paper investigates the optical properties and radiation shielding performance of borosilicate glasses containing chromium trioxide (CrO3) and strontium titanium oxide (SrTiO3). The optical characteristics, including refractive index, absorption coefficient, and transmission behaviour, were thoroughly analysed to gain insights into the transparency and light-carrying capabilities of the glasses. Additionally, the radiation shielding parameters were obtained by utilizing both FLUKA simulation and the XCOM program. The obtained radiation shielding data were then compared and discussed to assess the effectiveness of the glass compositions as shielding materials against ionizing radiation. The results provide a comprehensive understanding of the optical properties and radiation shielding capabilities of the studied glasses, contributing to the development of novel and efficient materials for radiation protection in various applications, including nuclear medicine, industrial radiography, and space exploration. The findings presented in this study offer valuable information for the design and optimization of borosilicate glasses containing CrO3 and SrTiO3 for effective radiation shielding in neutron-rich environments. [ABSTRACT FROM AUTHOR]

A systematic experimental study of the Y 2 O 3 –Al 2 O 3 –SiO 2 (YAS) compositional system has been carried out with a focus on nanoparticle formation in the high SiO 2 region, where nanoscale phase separation occurs. The unique capabilities of the aerodynamic levitation coupled to the laser-heating method have been exploited and compared to conventional melt-quenching. This systematic study has mainly focused on the region where melting temperatures exceed 1700 °C, which is the maximum temperature commonly available for the preparation of glass by conventional melt-quenching. The feasibility and the effect of the two synthesis routes on the preparation of glass samples have been compared. The prepared samples were characterised by X-ray diffraction, differential scanning calorimetry, Raman spectroscopy, and scanning and transmission electron microscopy. It is evident from the results that in the part of the phase diagram with SiO 2 content above 65 mol% and simultaneously Y 2 O 3 content below 17.5 mol%, the phase separation has led to the formation of amorphous SiO 2 nanoparticles. It has been shown that the size and distribution of the nanoparticles can be controlled not only by the chosen technology but also by changing the starting composition. [ABSTRACT FROM AUTHOR]

Owing to the development of glass 45S5 (Bioglass®) comprising 45 mol% SiO2, 24.5 mol% Na2O, 24.5 mol% CaO, and 6 mol% P2O5, different compositions of silicate glasses have been developed. When these silicate glasses contact an aqueous environment, such as body fluids, they induce apatite layer formation on their surfaces owing to ion exchange. In addition to promoting hard tissue formation, researchers have sought to enhance the antibacterial properties of these glasses, thereby resulting in the development of metal-doped silicate glasses. The addition of antibacterial metals (silver, copper, zinc, and gallium) to silicate glass offers a promising avenue for combating oral pathogens. In recent years, there has been growing interest in metal-doped phosphate glasses. The release of metal ions can be regulated by modifying the dissolution rate of the phosphate glasses. This review summarizes the metal-doped silicate and phosphate glasses that confer antibacterial activity. Future strategies for the development of dental biomaterials that incorporate metal-doped glass and exhibit antibacterial effects are discussed. [ABSTRACT FROM AUTHOR]

Quantification of the distribution of Q(n) species, representing the number of bridging oxygens (n) around a silicate tetrahedra in potassium disilicate glass, is achieved using the two-dimensional Phase-Adjusted Spinning Sideband (2D PASS) sequence. Furthermore, we compare the relative concentrations of each Q(n) species obtained through the PASS method with a previous study utilizing the Magic Angle Flipping (MAF) technique on the same glass composition. While MAF has been employed in prior research to enhance the precision of Q(n) species measurements in glasses, it necessitates a specialized probe capable of reorienting the rotor axis. In contrast, alternatives like MAT or 2D PASS are more appealing as they can be implemented using a conventional MAS probe. In this study, we demonstrate that the PASS experiment provides comparable accuracy to MAF while significantly reducing the required time. [ABSTRACT FROM AUTHOR]

The indicators of adhesion of adhesives based on copolymers of sodium 2-acrylamido-2-methylpropane sulfonate with acrylamide, methacrylamide, and sodium acrylate and methacrylate to silicate glass and paper products depending on the chemical nature of the comonomer and ratio of the monomer units in a macromolecule are determined. [ABSTRACT FROM AUTHOR]

An investigation was conducted to explore the optimum composition to fabricate a zinc silicate glass substrate for optoelectronic device applications. The composition was determined based on the empirical formula (ZnO)x-(SiO2)1-x, where x = 0.40, 0.50, 0.60 and 0.70 wt%, which was prepared by the conventional melt quenching technique. The focus is on characterizing the physical and structural aspects as well as the optical properties of the glass substrate. The physical properties of zinc silicate samples were assessed using the densitometer and their physical appearance. In addition, the materials' amorphous and glassy characteristics were verified using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) techniques. Finally, ultraviolet–visible (UV–Vis) spectroscopy and photoluminescence spectrometer were used to study the optical properties of samples. The density of the samples was observed to increase from 2805 to 3878 kg/m3 as the percentage of ZnO in the glass composition increased. X-ray diffraction analysis indicated the absence of sharp peaks in the samples containing up to 0.60 wt% of ZnO, suggesting the presence of an amorphous phase. Furthermore, the results of this study indicate that ZnO-SiO2 glass substrate samples favor direct forbidden transitions, with an increase in ZnO leading to higher absorption and consequently a lower band gap. The photoluminescence spectrum showed blue light emissions at 422 nm, associating with the variation of band gaps in the ZnO phase. Overall, from the interesting results achieved, this zinc silicate-based composite material at 0.60 wt% ZnO can be a potent candidate in optoelectronic applications, among other concentrations used in this study.

AbstractOwing to the development of glass 45S5 (Bioglass®) comprising 45 mol% SiO2, 24.5 mol% Na2O, 24.5 mol% CaO, and 6 mol% P2O5, different compositions of silicate glasses have been developed. When these silicate glasses contact an aqueous environment, such as body fluids, they induce apatite layer formation on their surfaces owing to ion exchange. In addition to promoting hard tissue formation, researchers have sought to enhance the antibacterial properties of these glasses, thereby resulting in the development of metal-doped silicate glasses. The addition of antibacterial metals (silver, copper, zinc, and gallium) to silicate glass offers a promising avenue for combating oral pathogens. In recent years, there has been growing interest in metal-doped phosphate glasses. The release of metal ions can be regulated by modifying the dissolution rate of the phosphate glasses. This review summarizes the metal-doped silicate and phosphate glasses that confer antibacterial activity. Future strategies for the development of dental biomaterials that incorporate metal-doped glass and exhibit antibacterial effects are discussed.

Acoustic velocities of a model basalt glass (64 mol% CaMgSi2O6 + 36 mol% CaAl2Si2O8) were measured along different pressure-temperature (P-T) paths. One set of experiments involved isothermal compression-decompression cycles, performed at temperatures of 300, 641, 823, and 1006 K and pressures up to 12.2 GPa. The other set of experiments involved constant-load heating-cooling cycles at temperatures up to 823 K and pressures up to 7.5 GPa. Both sets of experiments were performed in a multi-anvil apparatus using a synchrotron-based ultrasonic technique. Our results show that the glass compressed isothermally at 300 K (cold-compression) displays anomalously decreasing compressional (VP) and shear (VS) wave velocities with increasing pressure until ~8 GPa. Beyond 8 GPa, both VP and VS start to increase sharply with pressure and irreversible densification of the glass occurred, producing large hysteresis loops of velocities upon decompression. However, for the glass compressed isothermally at increasingly higher temperatures (hot-compression), the velocity minima gradually shift to lower pressures. At temperature close to the glass transition temperature Tg, the velocity minima disappear completely, displaying a monotonic increase of velocities during compression and higher VP and VS during decompression. In addition, constant-load heating-cooling experiments show that velocities generally decrease slightly with increasing temperature, but start to increase once heated above a threshold temperature (~650 K). During cooling the velocities increase almost linearly with decreasing temperature, resulting in higher velocities (~1.5–2.5% higher) when returned to 300 K. This implies that a temperature-induced densification may have occurred in the glass at high pressures. Raman spectra on recovered samples show that the hot-compressed and high-P heated glasses contain distinctly densified and depolymerized structural signatures compared to the initial glass and the cold-compressed glass below the velocity transition pressure PT (~8 GPa). Such densification may be attributed to the breaking of bridging oxygen bonds and compaction in the intermediate-range structure. Our results demonstrate that temperature can facilitate glass densification at high pressures and point out the importance of P-T history in understanding the elastic properties of silicate glasses. Comparison with melt velocity suggests that hot-compressed glasses may better resemble the pressure dependence of velocity of silicate melts than cold-compressed glasses, but still show significantly higher velocities than melts. If the abnormal acoustic behaviors of cold-compressed glasses were used to constrain melt fractions in the mantle low-velocity regions, the melt fractions needed to explain a given velocity reduction would be significantly underestimated at high pressures. [ABSTRACT FROM AUTHOR]

Membrane technology is a promising method for gas separation. Due to its low energy consumption, environmental safety, and ease of operation, membrane separation has a distinct advantage over the cryogenic distillation conventionally used to capture light inert gases. For efficient gas recovery and purification, membrane materials should be highly selective, highly permeable, thermally stable, and low-cost. Currently, many studies are focused on the development of high-tech materials with specific properties using industrial waste. One of the promising waste products that can be recycled into membrane materials with improved microstructure is cenospheres—hollow aluminosilicate spherical particles that are formed in fly ash from coal combustion during power generation. For this purpose, based on narrow fractions of fly ash cenospheres containing single-ring and network structure globules, silicate glass/mullite composites were prepared, characterized, and tested for helium–neon mixture separation. The results indicate that the fragmented structure of the cenosphere shells with areas enriched in SiO2 without modifier oxides, formed due to the crystallization of defective phases of mullite, quartz, cristobalite, and anorthite, significantly facilitates the gas transport process. The permeability coefficients He and Ne exceed similar values for silicate glasses; the selectivity corresponds to a high level even at a high temperature: αHe/Ne—22 and 174 at 280 °C. [ABSTRACT FROM AUTHOR]

Quantification of water content in silicate glasses is of vital significance in understanding magma evolution and metamorphic anataxis. Here we provide a method for the determination of total dissolved water content and water speciation in silicate melts by confocal laser Raman spectrometry based on a set of hydrous rhyolitic glasses. A series of alumino‐silicate glasses with water contents from 0.33 to 9.05% m/m were synthesised in a piston cylinder apparatus. Synchrotron‐FTIR mapping shows that these glasses have relatively homogeneous distributions of dissolved water. Total water contents of the glasses were precisely measured by TC/EA‐MS and FTIR. Both external and internal calibration were established for the quantitative analysis of water content and water speciation in the silicate glasses based on excellent linear correlation between total dissolved water content and integrated area of the water Raman band. Furthermore, by decomposing the total water Raman bands into four Gaussians components, the relative concentration of water speciation (OH groups and molecules H2Om) dissolved in the glasses was determined with a similar trend to water speciation data derived from FTIR. We suggest that the relative concentration of water speciation can be estimated in rhyolitic glasses with 4–8% m/m H2O. Our work provides an accurate method to determine total water content and a potential tool to limit the relative concentration of water speciation dissolved in silicic glasses. [ABSTRACT FROM AUTHOR]

Chalcogenide (ChG) glasses with micro-nano structure arrays are increasingly demanded in infrared optical systems owing to their excellent antireflective properties, and can be mass-produced by precision glass molding (PGM). Nickel-phosphorus (Ni–P) plated molds are commonly used in the PGM process, but the Ni atoms tend to react with the ChG glass at high temperatures. In this study, we propose a novel two-step PGM process. A Ni–P mold is used to transfer antireflective micro-nano structure array to silicate glass. Then the silicate glass, which has a higher glass transition temperature (Tg) than the ChG glass, is used as the mold to replicate the antireflective structured surface to the ChG glass. The results show that the ChG glass micro-nano structure array has high forming accuracy and favorable infrared optical transmission characteristics. The silicate glass is proved to be an appropriate mold material for the ChG glass molding process. This work provides a novel type of the PGM techniques for ChG glass materials. [ABSTRACT FROM AUTHOR]

Raw materials significantly determine the final composition and properties of a fired ceramic. Raman analysis which characterizes micro- and nanostructures of (coloured) glazes, opacified or not, was applied to shards mostly collected before the 1960s, currently at the Louvre Museum, originated in Anatolia, the Caucasus, Iran and Central Asia, which are, for most of them, characterized by the use of black lines to separate coloured areas, and dated to the period between the 12th and 19th centuries. Measurements were carried out in the laboratory with a blue laser excitation and/or on the conservation site with a mobile device (green laser). Three types of glazes were identified by their nanostructure of the silicate network: (i) a lead-rich glaze analogous to that of Byzantine, Zirid to Hafsid and al-Andalus productions, (ii) a lead-alkali glaze typical of the Ottoman productions of Iznik-Kütahya, and (iii) a mixed (poor lead/lead-free)-alkali glaze typical of Safavid productions. The colour determines the precise composition of the glaze. The identification is not only based on the signature of the stretching mode of the SiO4 tetrahedron (position of the wavenumber of the component(s)) but also on the position and shape of the continuous luminescence of the Raman background, characteristic of the raw materials used. Lead-tin yellow, Fe-rich, Mn-rich and Cr-rich black pigments and opacifiers made of cassiterite and wollastonite were also identified. The results (type of glaze and deduced processing temperature) were discussed in the light of the ternary phase diagrams visualizing elemental composition determined in previous works and the microstructure examination on the polished section (defining single or multistep firing cycles). Continuity was highlighted on the one hand between the tiles of Bursa, Edirne and Istanbul (Ottoman Iznik-like production) and on the other hand between those of Samarkand area (Timurid) and Iran. The procedure was then applied in the study of three objects (two dishes and a bowl) which are very representative of the productions of the Turkish-Persian cultural areas: a polychrome mina'i cup with decoration representing a rider, an Ottoman Iznik fritware with polychrome floral decoration, and a blue-and-white Safavid ceramic with a decoration representing a shrub. [ABSTRACT FROM AUTHOR]

The effects of silicate glass particle size and Y 3 Al 5 O 12 : Ce3+ (YAG: Ce3+) phosphor doping concentration on the optical properties of phosphor-in-glass (PiG) samples were investigated. When the average particle size of glass powder was 160, 100, 60, and 30 μm, the transmittance of silicate glass with a thickness of 0.6 mm was 68%, 78%, 62%, and 54%, respectively. With the mixing of 4 wt% YAG: Ce3+ phosphor in each component of silicate glass, the transmitted luminous flux of PiG gradually increased with the increase of transmittance, reaching a maximum of 179.5 lm. Simultaneously, we found that with the increase in transmittance, the photoluminescence (PL) intensity of PiG gradually decreased; however, the total luminous flux of PiG has independent of transmittance. When the doping concentration of YAG: Ce3+ phosphor was 4 wt%, PiG achieved a maximum efficient white light emission of 212.61 lm/W under blue laser excitation at 2.31 W. All results indicate the outstanding feasibility of the prepared YAG-PiG in high-power/high-brightness white light-emitting diodes (WLEDs). [ABSTRACT FROM AUTHOR]

To improve the corrosion resistance of Al2O3-13 wt.% TiO2 (AT13) coatings prepared by plasma spraying, CaO-MgO-Al2O3-SiO2 silicate glass powder was mixed with AT13 in different proportions (Glass/AT13 = 0/10, 1/10, 2/10 and 3/10, by mass). The morphology and structure of the coatings were characterized by field emission scanning electron microscopy/energy spectrometry, x-ray diffraction and confocal laser scanning microscopy. Their corrosion resistance was evaluated by immersion corrosion and electrochemical corrosion tests. The results show that the glass-doped composite coatings have lower porosity, higher microhardness and lower roughness than the pure AT13 coating. Therefore, the glass-doped coatings exhibited better corrosion resistance than the sealed AT13 coating. In addition, the composite coating with the doping ratio of 2:10 maintained the best overall corrosion resistance with low corrosion zones, low corrosion current values, high pitting potential and high polarization resistance. Therefore, the proper addition of glass frit, with its excellent characteristics of low viscosity and high fluidity at high temperatures during plasma spraying, can fully compensate for the high porosity of ceramic coatings. Proper doping with glass has excellent potential application to improve the corrosion resistance and service performance of plasma-sprayed ceramic coatings. [ABSTRACT FROM AUTHOR]

Effects of Ba+-ion implantation into silicate glass and its after annealing on the composition, density of electronic states, and parameters of the energy bands are investigated by Auger electron, ultraviolet photoelectron, and light-absorption spectroscopic techniques. It is shown that nonstoichiometric oxides of Si, Pb, and Ba, as well as unbound atoms of the same elements, are formed in the ion implanted layer after ion implantation. As a result, there is a significant change in the electronic structure of silicate glass, in particular, the band gap decreases by ∼2 eV. After annealing at T = 1000 K, unbound Si, Pb, and Ba atoms disappear in the ion implanted layer (within the limits of sensitivity of an Auger-electron spectrometer) and stoichiometric oxides such as SiO2, PbO, and BaO are formed. [ABSTRACT FROM AUTHOR]

Rare‐earth‐doped transparent glass shows great potential in white light‐emitting diodes (wLEDs) application due to its excellent optical and luminous properties. Currently reported commercial wLEDs have a drawback in red emission missing, which leads to a relatively low color rendering index (CRI) and a relatively high correlated color temperature (CCT). In this work, Ce@Eu Sr–Si–O glass is fabricated using a high‐temperature quenching method. The white light is available when the ratio of Ce3+/Eu3+ equals 1, and the emitting color can be adjusted from blue to red by controlling the ratio of Ce3+/Eu3+. To further optimize the white light, Eu3+ ions can be reduced to Eu2+ according to the reaction of 6Eu3+ + 2N3− → 6Eu2+ + N2↑ by introducing Si3N4. As a result, the standard white light emission can be achieved in the Ce@Eu silicate glass contributed by the blue light from Ce3+, red light from Eu3+, and yellow–green light from Eu2+ (two elements, three emission). This glass shows excellent luminous properties, such as a color coordinate is (0.3651, 0.3269) in CIE 1931 color coordinate diagram, a CRI is over 70, a high quantum yield of 36.02%, and a CCT of 4117 K. [ABSTRACT FROM AUTHOR]

Rare‐earth‐doped transparent glass shows great potential in white light‐emitting diodes (wLEDs) application due to its excellent optical and luminous properties. Currently reported commercial wLEDs have a drawback in red emission missing, which leads to a relatively low color rendering index (CRI) and a relatively high correlated color temperature (CCT). In this work, Ce@Eu Sr–Si–O glass is fabricated using a high‐temperature quenching method. The white light is available when the ratio of Ce3+/Eu3+ equals 1, and the emitting color can be adjusted from blue to red by controlling the ratio of Ce3+/Eu3+. To further optimize the white light, Eu3+ ions can be reduced to Eu2+ according to the reaction of 6Eu3+ + 2N3− → 6Eu2+ + N2↑ by introducing Si3N4. As a result, the standard white light emission can be achieved in the Ce@Eu silicate glass contributed by the blue light from Ce3+, red light from Eu3+, and yellow–green light from Eu2+ (two elements, three emission). This glass shows excellent luminous properties, such as a color coordinate is (0.3651, 0.3269) in CIE 1931 color coordinate diagram, a CRI is over 70, a high quantum yield of 36.02%, and a CCT of 4117 K. [ABSTRACT FROM AUTHOR]

Numerous studies on the effect of the femtosecond laser pulses in oxide glasses have been achieved over the last two decades, and several specific effects pointed out. Some of them are classical with respect to a laser treatment, such as thermally related effects, and are widely taken into account for applications. Other effects are directly induced by light, caused by its intricated spatiotemporal structure and associated properties: ponderomotive and polarization effects or coherence within the focal volume. These effects enable the development of forces that can lead to orientation effects. Among the specific resulting transformations from the light-induced effects in glass, the formation of so-called nanogratings was first pointed out in 2003 in silica glass. From this date, asymmetric organization into parallel nanoplanes, perpendicular to the laser polarization, have been found in many vitreous and crystalline compounds. While it is accepted that they arise from the same origin, i.e., a plasma organization that is eventually imprinted inside the material, uncertainties remain on the formation process itself. Indeed, since it exists several categories of nanogratings based on the final structuring (nanoporous phase separation, crystallization, and nanocracks), it can be expected that several processes are at the roots of such spectacular organization. This paper describes an approach based on electrochemical potential modified by an electronic excitation. The electric field induced during this process is first calculated, with a maximum of ~4500 kV/µm and a distribution confined within the lamella period. The maximal chemical potential variation is thus calculated, in the studied conditions, to be in the kJ/mol range, corresponding to a glass-to-crystal phase transition energy release. The kinetics aspect of species mobility is subsequently described, strengthening the proposed approach. [ABSTRACT FROM AUTHOR]

Two sets of model glasses differing by molar fractions of bridging (BO) and non-bridging (NBO) oxygens and of Q³ and Q⁴ structural units were prepared. Glasses in each set are isostructural on BO/NBO level that means the fractions of BO and NBO are the same. The groups mimic Float glass and the commercial barium crystal glass. The study compares three different ways of glass surface preparation in order to find the most realistic results of chemical analyses. The studied surfaces were: i) the original surface created by melting and exposed to the ambient atmosphere, ii) polished sample routinely prepared in way common for X-ray microanalysis, and iii) freshly fractured surface. Glasses were also analysed by XRF and the results were compared with the EDX analysis. The data suggest the EDX analysis of fresh fractures provide the most realistic composition. The comparison of XRF and EDX provide useful insight into the differences between two methods and further enhances the complexity of the glass surface study. While XRF offers a reliable analysis of bigger volume and provides averaged composition, EDX yields a more realistic surface and local composition. EDX of freshly prepared fractures revealed strong sodium enrichment on the surface due to the active participation of this element in the relaxation of the newly formed surface.

BACKGROUND The precise measurement for Na and K in silicate glass is usually difficult in electron probe microanalysis (EPMA). Ti-containing silicate glass has an important value in basic scientific research and application technology development, and it is urgent to carry out accurate composition analysis to provide important data support for further scientific research work. The glass is of amorphous form and damageable under electron bombardment. Moreover, the alkali Na and K elements can easily diffuse and migrate during the electron bombing. Therefore, it is often necessary to set the appropriate analysis conditions through conditional experiments to ensure that the sample can be kept as stable as possible under these conditions, so that relatively accurate quantitative analysis results can be obtained. OBJECTIVES To determine the proper analytical conditions for Na and K analyses in the silicate glass. METHODS Electron probe quantitative analyses for Na and K were performed in the synthetized silicate glass samples of NTS (Na2O-TiO2-SiO2) and KTS (K2O-TiO2-SiO2). By changing the probe diameter (10-100μm), beam current (3nA, 5nA and 10nA) and count time (10s, 20s, 30s and 40s) orderly in a series of experiments, the optimal analytical conditions for accurate quantitative results were established. RESULTS The results showed a systematic change with positive trend of Na, K, Si and Ti contents with probe diameter and count time increases, but a contrasting trend for beam current. In most cases, the conditions of larger probe diameter up to 80-100μm and lower beam current (3nA or 5nA) provided the highest Na or K content that maximumly approaches the normal value before synthesis. This was different from the previous glass analysis conditions, which may be related to the high Na, K and Ti content of the samples. In grid analysis for elemental map modeling, certain correlation(s) among Na, K, Si and Ti were revealed, which provided further perspectives for potential chemical bonds, i.e. crystallochemical structure of the sample. CONCLUSIONS A larger probe diameter of 100μm and lower beam current of 3-5nA for Na and K analyses in silicate glass are recommended for optimum analysis.