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To decipher the effects of replacing alkali with zinc on thermo-mechanical properties, a series of borosilicate glasses with the molar compositions of 70.65SiO 2 ·21.09B 2 O 3 ·1.88Al 2 O 3 ·1Li 2 O·(5.38- x)R 2 O· x ZnO (x = 0, 0.34, 0.67, 1, 1.34, 2.69, 4.04, and 5.38) were prepared. Upon adding a slight quantity of ZnO, a local extreme point for glass transition temperature (T g) appears. This behavior is deciphered to be originated from two opposite factors. On one hand, T g reduces as a characteristic of the colligative properties for a dilute solution; in addition, T g rises due to the higher field strength, bond energy and covalent characteristic of zinc cations compared to that of alkali ions. Otherwise, based on the evolution of intermediate-range clusters revealed by infrared, Raman and NMR spectra, we elucidate the atomic-scale structural origin, which leads to the nonlinear evolution of elastic moduli and coefficient of thermal expansion with the molar ratio of [ZnO]/([R 2 O]+[ZnO]). [ABSTRACT FROM AUTHOR]

This article uses a high-temperature sintering imaging instrument to test the flowability of borosilicate glass melt doped with Cr 2 O 3 , and establishes a mathematical model for high-temperature glass melt spreading. Discuss the glass melt from a thermodynamic perspective by combining model interpretation with experimental characterization. The results indicate that the thermodynamic judgment formula for high-temperature flow spreading of borosilicate glass is: Q ≥ ρ [ A 0 exp (− T / k 0) + S 0 ] − M · δ [ A 0 exp (− T / k 0) + S 0 ] 1 / 2 . To improve the high-temperature flow ability of borosilicate glass, it is necessary to increase the spreading activation energy Q. On the other hand, it is necessary to reduce the spreading coefficients A 0 、 k 0 and S 0. As a refractory metal oxide and active oxide, Cr 2 O 3 plays a role in reducing the spreading coefficient of glass systems. [ABSTRACT FROM AUTHOR]

The gamma shielding parameters of an admixture of waste borosilicate glass (BS) and geopolymer (GP) made from activated metakaolin are presented in the present study. The influence of the BS quantity on the density and different gamma shielding quantities is investigated over a wide gamma energy range. Four batches of the G-BS composite were prepared using the solid-state diffusion method, containing 0 (G), 10 % (G-10BS), 20 % (G-20BS), and 30 % (G-30BS) by weight of BS, respectively. The chemical compositions of the G-xBS samples were determined through X-ray fluorescence spectrometry. In addition, the density of the BS-doped geopolymers was determined using the liquid displacement method using deionized water as the displacement fluid. The theoretical determination of estimating shielding parameters began by estimating the mass (μ ρ) and linear (μ) attenuation coefficients of the geopolymers for photon energies in the range of 15 keV to 15 MeV using the XCOM data library. The B and Si content and density of the geopolymer samples increased as the BS weight proportion increased in the geopolymer. The values of the attenuation coefficients (ACs) decreased with energy. For μ, the decrease was from 9.1533 to 0.0355 cm−1, 6.7486 to 0.0374 cm−1, 10.2964 to 0.0396 cm−1, and 10.7722 to 0.0414 cm−1, while for μ ρ , it was 5.3217 to 0.0206 cm2 g-1, 5.3860 to 0.0206 cm2 g-1, 5.3627 to 0.0206 cm2 g-1, and 5.3594 to 0.0206 cm2 g-1, for G, G-10BS, G-20BS, and G-30BS, respectively. There are no significant differences between the photon energy absorption capacity of the geopolymers, especially at energies greater than 1 MeV. The photon buildup factors of the G-xBS samples have very close relative values with no clear order. The introduction of waste borosilicate glass is therefore a way of improving the photon attenuation capacity of geopolymer and, therefore, the potential of shielding applications of geopolymer-based concrete. [ABSTRACT FROM AUTHOR]

The present study investigates in-vitro biomineralization, mechanical, and tribological properties of bioactive borosilicate glass composed of 31B 2 O 3 –20SiO 2 -(24.5-x)Na 2 O-24.5CaO and xCuO (mol%). Glass was manufactured using conventional melt-quench technique, utilizing chemicals partially derived from bio-waste, with varying copper oxide (CuO) content (x = 0, 1, 3, and 5). In-vitro study was conducted by immersing the specimens in simulated body fluid for 21 days. The formation of apatite layer was confirmed using FTIR, XRD and FESEM-EDS. Vicker's micro hardness tester and a universal testing machine measured hardness and compressive strength, while a pin-on-disc tribometer assessed wear. MTT assay was performed for all the specimens using osteosarcoma MG63 cell line. The study revealed that substituting copper in place of sodium increased the ion dissolution and improved the formation of the apatite layer hence, enhanced the bioactivity, however, accompanied by a gradual decrease in hardness and compressive strength. BSG-0 exhibited the highest hardness (6.64 GPa) and compressive strength (86.81 MPa), while wear resistance weakened with higher CuO content, notably in BSG-5 with the highest specific wear rate (0.072 mm³/N-m) under a 5 N load. Although MTT assay showed non-toxicity for all specimens, except BSG-5, the compounds demonstrated cell tolerance and growth stimulation. In conclusion, the study suggests that CuO-doped borosilicate glasses exhibit superior bioactivity, making them potentially effective for bone filling, wound healing, and dental applications, despite a compromise in mechanical strength and wear resistance. [Display omitted] [ABSTRACT FROM AUTHOR]

Lead-free tin-based perovskite quantum dots (QDs) are considered the most promising alternatives to lead-based perovskites, but their potential application is hindered by poor stability. This issue was addressed by preparing amorphous glass-protected CsSnBr3 QDs through meticulous optimization of the glass structure. Intriguingly, the self-crystallization of the CsSnBr3 QDs occurred without needing heat treatment. We found that the CsSnBr3 QDs glass-ceramic is composed of two phases, SnO2 and CsSnBr3, of which SnO2 is the main phase. At the same time, the tunability of the luminescence color can be achieved by changing the silicon–boron ratio and melting temperature in the glass matrix. Moreover, due to the complete encapsulation of the quantum dots by the glass matrix, the CsSnBr3 QDs glass-ceramic exhibited remarkable stability and a high photoluminescence quantum efficiency (51.5%). Subsequently, the CsSnBr3 QDs glass-ceramic was incorporated with an ultraviolet chip to produce a white light-emitting diode (WLED), and its potential application in plant growth was explored. [ABSTRACT FROM AUTHOR]

Borate glasses are of interest for many electronic applications like electronic packages and in vacuum systems as sealing glass. The aim of this work is to study the effect of Pb2O3 and SiO2 additives on the structural and characteristics of borate glass. Binary borate glass of BaO.B2O3 was synthesized by melt-quenching technique. The additives were introduced to the glass by substitution with BaO and B2O3. Two Batches of six recipes were prepared. All the synthesized glasses were transparent. The glass transition temperature (Tg) has varied according to the chemical composition. Recipe G3 exhibits the lowest Tg around 440°C, while G2 and G4 show high thermal stability. Coexisting of Pb2+ and Si4+ led to high dielectric constant for glass G5 and G6. [ABSTRACT FROM AUTHOR]

Microstructural evolution of borosilicate glass–sulfate (BaSO4 or Na2SO4) mixture was observed in situ using a high‐temperature confocal scanning laser microscope. The phase compositions and sulfate retention of the mixture at different temperatures were also examined. The results indicate that for the glass–BaSO4 sample (abbreviated as BS), the borosilicate glass begins to melt at about 900°C, and the triangular BaSO4 crystals grow obviously between 900°C and 1100°C. At temperatures above 1100°C, the BaSO4 crystals gradually melt and decompose. For the glass–Na2SO4 sample (abbreviated as NS), strip‐shaped BaSO4 crystals begin to form at about 820°C after the borosilicate glass melting, and then gradually melt with further increasing temperature. When the temperature increases to 1000°C, the upper layer of the NS sample possesses Na2SO4, LiNaSO4, and BaSO4 phases, while the lower layer possesses an amorphous phase. Moreover, the SO3 retention in the BS sample remains almost unchanged with temperature increases from 900°C to 1100°C, and then decreases with further increasing temperature. The SO3 retention retained in the NS sample decreases rapidly at temperatures above 900°C. These findings can provide a guidance for vitrifying sulfur‐rich high‐level liquid waste. [ABSTRACT FROM AUTHOR]

Progress in glass science has given rise to innovative functional glasses, unlocking significant applications for creating cutting-edge materials such as solid-state batteries, solar cells, optical reinforcement, and medical technologies. In this study, rice husk silica, Bismuth (Bi) and Tin (Sn) oxide ores were used to fabricate a novel glass series. The electrical conductivity (i.e., dielectric constant) of the glasses increased with the dopant's gravimetric levels. The novel glass series also possesses good optical non-linearity with metallisation criteria ranging from 0.35 to 0.40, which points to a novel non-linear optical material. The non-bridging oxygen content in the new glasses exceeds the bridging oxygen, indicating high polarisation. The transmission coefficient decreased with increasing dopant concentration from 0.76 to 0.75, while the reflection loss decreased from 0.37 to 0.38. For the Caesium-137 energy, GS6 has a minimum HVL of ∼5.02 cm, which is ∼20 % lower than that of commercial Pb/Ba glass. For the two energies, GS6 has the least MFP, suggesting that the addition of dopants improved the efficiency of the glass attenuation. Process capability analysis based on Caesium-137 (661.7 keV) and overall performance analysis of the fabricated glass series revealed that GS3 glass (15 wt% dopant) is the optimal material, even outperforming the commercial Pb/Ba glass. Although Cobalt-60 (1253 keV) yielded comparable outcomes, concentrations beyond 15 wt% in GS3 showed marginal enhancements in the photon attenuation parameters of the glasses. Hence, the fabricated GS3 and the circular synthesis method of the glasses are cost-effective for low-energy gamma/X-ray shielding. The percentage deviation between the experimental data for MAC and that of Monte Carlo simulations for Cs-137 and Co-60 energies are both within 10 %, which validates the methods of this paper. [ABSTRACT FROM AUTHOR]

As a fission product in high‐level radioactive nuclear waste, Mo has low solubility in borosilicate glass. Fe2O3 is not only a prevalent transition metal element but also a major corrosion product in high‐level radioactive nuclear waste. Against this backdrop, the effect of Fe2O3 content on the structure and chemical durability of typical molybdenum‐containing sodium borosilicate glasses for nuclear waste immobilization are studied. The results show that the samples containing more than 3.85 mol% Fe2O3, a completely homogenous amorphous glass sample is obtained. Moreover, the mechanism of the effect of Fe2O3 on the solubility of Mo is discussed in detail. In this work, a portion of Fe3+ is reduced to Fe2+ and enters into the glasses as a charge compensation ion as Fe2+O6. Concurrently, Fe3+ ions contribute to the formation of the glass networks as Fe3+O4. Iron incorporation can improve the chemical durability of the sample. [ABSTRACT FROM AUTHOR]

The stress distribution in sealing glass is one of the most concerning issues for glass‐to‐metal (GtM) seals. In this study, photoluminescence spectroscopy was applied by exploiting the piezospectroscopic effect of Cr‐doped α‐Al2O3 (ruby), and the overall stress distribution along the radius of a concentric seal was detected and analyzed. It was discovered that the compressive stress first increased and then decreased at the edge of the seal. The maximum compressive stress of 91 MPa was detected at ∼20 µm from the interface and was ascribed to the interaction between the glass and surface oxide film of the metal. Stress distributions in pore regions were also investigated and obvious stress fluctuations were observed clustering around pores. A circle of compressive stress was observed around the pores in a single glass without a metal housing; for the pores in the center of the concentric seal, the stress distribution was dominated by the inner contraction of the metal housing; and for the pores near the edge of the seal, the concentration of tensile stress located perpendicular to that of the compressive stress. This study demonstrates a high‐resolved and nondestructive method to detect the stress field and explores the potential for future tailorability of stress distribution in GtM seals. [ABSTRACT FROM AUTHOR]

Knowledge of the structural organization of nuclear waste glasses at the atomic scale is the basis for further studies of macroscopic properties (e.g., fracture toughness, chemical durability, and leaching rate). Recent studies have focused on the iodine dissolution mechanism in oxide‐based glasses synthesized under high‐pressure conditions, but there is still a lack of key information on the extent of the modifications caused by iodine entering the glass network. We therefore decided to conduct an in‐depth study by nuclear magnetic resonance on two series of aluminoborosilicate glasses synthetized under high pressure conditions and doped with either I2 or I2O5. The obtained 11B, 23Na, and 27Al nuclear magnetic resonance (NMR) spectra were fitted and correlated with the iodine content in order to find possible relationships with the local environment change for the probed cations. These data showed that iodine has no effect on the coordination of aluminum and very little effects on that of boron. In contrast, we found an expected relationship of the I content with the 23Na NMR parameters. In comparison with previous studies on the non‐bridging oxygen (NBO) distribution in aluminoborosilicate, we suggest that Na+ is mainly scavenged from silica tetrahedra with one or two NBO (Q3${Q}^3$ or Q2${Q}^2$) as no boron planar triangles with one NBO are expected for such compositions. From those information, we establish a model for iodine dissolution in nuclear waste glass that is consistent with previous studies. [ABSTRACT FROM AUTHOR]

Borosilicate glass has good light transmittance and stable chemical property, which is an ideal material for microfluidic chip matrix, However, brittle fracture is easy to occur during processing, which is a typical material difficult to process. This limits the surface accuracy. In recent years, longitudinal torsional ultrasonic vibration–assisted milling (LTUVAM) has been proposed as an effective way to machine hard and brittle materials. To elucidate the mechanism of material removal methods and elaborate the material removal mechanism during longitudinal torsional ultrasonic vibration–assisted milling process, this paper established a 3D morphology prediction model to investigate the material removal method. Firstly, the three-dimensional surface morphology model was created by describing the intricate tool path and the workpiece surface morphology reconstruction process under ultrasonic conditions while also considering the tool run-out effect. The model exhibited a certain degree of scalability, enabling the acquisition of various process morphology prediction models by altering the tool coordinates via matrix manipulation. Secondly, the accuracy of the model was verified by longitudinal torsional ultrasonic processing experiments. Thirdly, longitudinal torsional ultrasonic vibration–assisted milling experiments and longitudinal ultrasonic vibration–assisted milling experiments were conducted, and the surface roughness of the machined workpieces was measured. The experimental results show that LTUVAM further reduces the roughness compared with LUVAM, indicating that the reduction ratio reaches a maximum value of 61.06% at the spindle speed of 16,000 RPM, and then, the reduction ratio decreases to 42.88% with the increase of spindle speed. Combining modeling and experimental results, we concluded that LTUVAM was more advantageous in achieving plastic material removal and enhancing the surface quality of the machined surface compared to LUVAM. And under the same process conditions, as the spindle speed increases, the surface roughness of the workpiece increases first and then decreases. [ABSTRACT FROM AUTHOR]

New borosilicate glass (BSG) systems doped with different rare earth (RE) ions; Dy, Y, Nd and Ho, were molten by the common melting-quenching technique. XRD analysis exhibited the amorphous glassy states of the samples. Some optical, physical, and spectral features of the glasses were inspected within the influence of progressive gamma irradiation doses up to 300 kGy. FTIR spectra displayed the large structural stability against 200 kGy of gamma radiation which is correlated to the dual contribution of silicate (SiO 4), and borate (BO 3 and BO 4) vibrational bands. Optical UV–visible spectra revealed common peaks in the range 215–340 nm owing to the various valence states of the present transition metal (TM) ions e.g., Fe2+/Fe3+, Cu+/Cu2+, Ti3+/Ti4+, Zn2+ and the introduced RE ions. By following the dosimetric characteristics of the glasses up to 300 kGy, only Nd-BSG and Ho-BSG were sensitive to gamma rays, and a systematic obvious increase was detected for the characteristic peaks of Nd- BSG at 582 nm and Ho-BSG at 450 nm, however, the remaining samples (BSG, Dy-BSG, and Y-BSG) did not achieve a systematic change. Both Nd-BCG and Ho-BSG response curves showed a linear part extended up to 150 kGy. Nd-BCG and Ho-BSG are humidity-independent with satisfactory stability through 30 days of storage. Many optical and physical parameters for Nd- and Ho- BSGs were studied at the whole dose range up to 300 kGy e.g, optical band gap energy (Eopt), density (ρ), refractive index values (n Eopt , n k-s , n m and n R–S), electronegativity (χ), electron polarizability (∝°) and optical basicity (⋀), all revealed either a gradual increase or decrease with the progressive irradiation doses. The study recommends the hopeful usage of the prepared Nd and Ho- BSGs as high-dose radiation dosimeters in a useful high-dose range up to 300 kGy of gamma radiation. [ABSTRACT FROM AUTHOR]

Researchers have extensively studied borate bioactive glass (BBG) for bone regeneration and wound healing applications. In the current study, 13-93B3 (54.6% B2O3, 22.1% CaO, 7.9% K2O, 7.7% MgO, 6.0% Na2O, and 1.7% P2O5) was synthesized using a sol–gel technique and doped with different molar concentrations of Cu (0.01, 0.05, and 0.25 M) into BBG for possible biomedical applications. Then, the antibacterial activity was tested against E. coli and S. aureus. The maximum zone of inhibition against S. aureus was achieved at 100 μg/mL of 0.25 M Cu-doped BBG. At 50 μg/mL of 0.25 molar copper concentration, E. coli showed a significant reduction in colony-forming units. Hydroxyl radical production, influenced by the BBG powder, was most effective against S. aureus, followed by E. coli. Protein leakage studies demonstrated significant leakage after treatment with BBG powder, demonstrating a strong effect on bacterial strains. This shows a change in protein synthesis, which is essential for central metabolism and gene transcription, affecting proteins in the periplasm and inner and outer membranes. Furthermore, carbohydrate leakage studies showed that BBG is effective against all three categories of cellular carbohydrate, namely membrane-bound, transmembrane, and intracellular carbs. This study focuses on the diverse antibacterial processes of Cu-doped BBG, which has emerged as a promising contender for biological applications that require strong antibacterial characteristics. [ABSTRACT FROM AUTHOR]

The work aims to study the evaporation process of borosilicate glass used for strengthening of silica fiber light guides. The composition of glass after high-temperature treatment was determined based on refractive index measurement. It was found that at temperature 2100 °C two-component SiO2-B2O3 glass vaporizes without changing its composition at a boron oxide content of ≈ 4 mol% in both oxygen and nitrogen atmospheres. The IR absorption spectra of borosilicate glass indicate the absence of boroxol rings of B2O3, which can explain the low partial pressure of its vapors compared to the ideal melt state. It is experimentally shown that the content of only 1 mol % B2O3 in the outer cladding of silica fiber increases its strength by 10% when the drawing temperature is reduced to 1900 °C. Such a small addition of boron oxide to silica glass decreases its viscosity, ensuring the occurrence of compressive stresses in the borosilicate cladding. [ABSTRACT FROM AUTHOR]

In this study, the results of the investigation of the influence of Al atoms on the structural characteristics of ZnO films obtained by the sol-gel method are presented. It has been determined that the glass substrates consist of subcrystallites with dimensions of 28.6 nm, having cubic unit cells with lattice parameters a = 0.3336 nm, and their surfaces belong to the crystallographic orientation (111). It has been identified that the grown thin ZnO films consist of subcrystallites with dimensions of 39.5 nm, having a wurtzite structure with lattice parameters a = b = 0.3265 nm and c = 0.5212 nm, respectively. It has been determined that at the boundaries of the division of these subcrystallites, polycrystalline regions with sizes of 12.6 nm, 28.3 nm, 30 nm, and 33 nm are formed. Additionally, nanocrystallites with sizes of 56.8 nm self-assemble on the surface areas of the deposited films. The increase in the values of the “c”axis of the hexagonal crystal lattice of ZnO films by 0.0009 nm when doping Al atoms from 1% to 5% is explained by the shift of the main structural line (002) at small angles (Δθ=0.12°). It has been established that nanocrystallites with lattice parameters аn = 0.5791 nm, belonging to the spatial group Fd3m, self-assemble on the surface areas of ZnO:Al films. the curve due to the presence of a monoenergetic level of fast surface states at the heterojunction.

One major factor impeding the design of nuclear waste glasses with enhanced waste loadings is our insufficient understanding of their composition–structure–durability relationships, specifically in the environments the waste form is expected to encounter in a geological repository. In particular, the high field‐strength cations (HFSCs) are an integral component of most waste streams. However, their impact on the long‐term performance of the glassy waste form remains mostly undeciphered. In this context, the present study aims to understand the impact of some HFSCs (i.e., Nb5+, Zr4+, Ti4+, and La3+) on the dissolution behavior of alkali/alkaline‐earth aluminoborosilicate‐based model nuclear waste glasses in hyper‐alkaline media. At pH = 13, the studied glasses dissolve through the dissolution–reprecipitation mechanism, with Ca precipitation being the most vital step to passivation. In Ca‐free glasses, although the HFSCs slow down the forward rate, they do not seem to impact the residual rate behavior of glasses. The presence of Ca2+, however, initiates the rapid precipitation of network polymerizing HFSCs (i.e., Nb5+, Zr4+, and Ti4+) into a Ca2+/HFSCs‐based passivating layer, thus suggesting a synergy between Ca2+ and HFSCs that contributes to the enhanced long‐term durability of the glasses. Such synergy is not strongly evident for La3+, but instead, a potential La/Si affinity is observed upon the formation of the alteration layer. [ABSTRACT FROM AUTHOR]

Due to the adoption of fluorescent powder encapsulated by organic resin, commercial light emitting diodes (LEDs) suffer from low thermal stability and poor light quality under high temperature, and luminescent glass is one of the effective ways to solve this problem. A series of borosilicate (B 2 O 3 –SiO 2 –Al 2 O 3 –PbO-Dy 2 O 3 –Eu 2 O 3 , marked as BSAP: DyEu) was prepared by the gas suspension technique. The basic characterization test indicate that the prepared glass has excellent thermal stability and stable structure. The optical properties of the luminescent glass were investigated in detail. By changing the Eu3+ doping amount, the Dy3+/Eu3+ co-doped glass can realize warm white light emission. The temperature-variable fluorescence spectra of BASP: Dy1.25Eu1.0 were analyzed, and the glass can produce strong warm white light emission in a wide temperature range. At 700 K, the luminous intensity of the glass remains above 38.49 % of the room temperature, and the chroma shift ΔC = 8.57 × 10−3. In addition, the w- LED device based on commercial GaN chip and BSAP: DyEu glass realizes warm white light output with excellent correlated color temperature (3063 K) and high color rendering index (90.3). The analysis shows that Dy3+/Eu3+ co-doped borosilicate glass can be used as a candidate material for w- LED applications. [ABSTRACT FROM AUTHOR]

Halide perovskite quantum dots (QDs) glass has attracted much attention in the field of optoelectronics, but its photoluminescence (PL) properties and water stability still need further improvement. In this work, the melt-quenching method is used to successfully precipitate CsPbBr 3 QDs in borosilicate glass. By increasing the concentration of ZnO, the photoluminescence quantum yield (PLQY) of CsPbBr 3 QDs glass is enhanced up to 30 times from 1.91 % to 65.87 %. The results demonstrate that the introduction of ZnO loosens the glass network structure, which contributes to the QDs to precipitate. In addition, it can be found that the PL intensity maintains 91.68 % of the initial PL intensity after 30 days of immersion, which is attributed to ZnO delays the corrosion of borosilicate glass by water. The effect of ZnO-modified borosilicate glass structure on PL and stability provides a certain reference value for further research on QDs glass, and the good PLQY and water stability make ZnO-modified CsPbBr 3 QDs glass a potential material in the field of WLEDs. [ABSTRACT FROM AUTHOR]

In order to increase solubility of sulfur in borosilicate glass, SO42- ions in simulated high-level liquid waste (HLLW) with relatively high content of sulfur and sodium were pretreated by adding Ba(NO3)2 solution, and then borosilicate glass waste form was prepared by melt-quenching method. The effects of pretreated HLLW on the structure and leaching resistance were mainly investigated. The results show that the waste loading can be increased to 23% (mass fraction) without phase separation after the Ba(NO3)2 pretreatment. The normalized elemental mass loss of Na, B and Si of the HLLW-loaded samples are one order of magnitude lower than that of the pure borosilicate glass. Furthermore, the leaching resistance of the glass waste form has no significant change with increasing HLLW content. 11B and 29Si MAS NMR analyses indicate that part of BO3 transforms into BO4 structural units and a polymerization of the glass network occurs after HLLW addition. [ABSTRACT FROM AUTHOR]

It is essential to treat high-level liquid waste (HLLW) in a secure and effective manner. As a result, we first propose rapid vitrification of simulated HLLW using an ultra-high power laser. First, a cured body with a mass of 24.4 kg was obtained by using ultra-high power laser sintering. Subsequently, four different locations of the curing body were tested and the measured performance indicators were all in accordance with the regulations. This demonstrates the potential of ultra-high power lasers in HLLW glass curing processes. [ABSTRACT FROM AUTHOR]

This study focuses on zinc-boro-soda-lime-silica (ZnO − B2O3 − SLS) glasses produced through fast-cooling melt-quenching. The influence of Eu3+ ions on glass properties is explored. As Eu3+ concentration rises, bulk density and molar volume increase from 3.423 to 3.484 g/cm3 and 21.760 to 23.768 cm3/mol, respectively. X-ray diffraction indicates amorphous phase dominance supported by glassy surface morphology. Ultrasonic measurements show the increasing and decreasing trend for ultrasonic velocities and elastic moduli with increasing Eu3+ concentration. Poisson's ratio of the samples signifies their low cross-link density behavior. Moreover, the ZBS-3Eu presents the highest microhardness value of 4.776 GPa. The sample's fractal bond connectivity varies from 1.814 to 2.051, suggesting a 2D structure. Likewise, the ZBS-3Eu glass sample exhibits the most rigidity attributed to its highest fg value of 0.075. These findings suggest that ZBS-3Eu has the potential for applications requiring high-strength glass. [ABSTRACT FROM AUTHOR]

This current investigation represents as well as discusses in detail the characterization of the thermal, mechanical, as well as electrical characteristics of titanium-based borosilicate glasses doped transition metal ions (3d) in addition to their corresponding glass–ceramics. The building structural units of the as-prepared glasses together with their glass – ceramic were characterized by the FTIR technique. FTIR spectra reveal characteristic silicate and borate groups vibrations, some of the TiO4 units are formed beside (TiO6) groups. The progressive enhancement in microhardness and thermal expansion values was recorded for glass – ceramic state that occurred as a result of the crystallization of nano-sized crystals throughout the glass matrix. The estimated electrical parameters which include permittivity (ε'), dielectric loss (ε''), AC conductivity (σac) capacitance (C), and dielectric loss demonstrated a distinctive variation in their values in accordance with the type of transition metal and /or the applied frequency. The prepared glass–ceramic was found to be suitable for use in electronics and solar cell applications based on its overall thermal and electrical properties. [ABSTRACT FROM AUTHOR]

Three borosilicate glass samples of 25 % Si 2 O – 30 % Na 2 O – 45 % B 2 O 3 doped with x Dy 2 O 3 (where x = 0, 2, and 4 mol %) were prepared using the melt quenching technique. Photoluminescence spectra for glass samples were studied when excited by 350 nm in the 400–800 nm range, where emission sharply increases for samples doped with 2 % Dy 2 O 3 (BSNDy2) at 580 nm after exposed to 30 kGy. Also, glass containing 2 % Dy photoluminescence constants, such as decay curves CIE chromaticity, was measured for all samples that gave three decay behaviors: slow, intermediate, and fast. Experimental lifetime (τ exp.), color coordination (X, Y), and yellow/blue intensity ratio (y/b) beside the color correlated temperature (CCT) were determined before and after being irradiated by 30 and 60 kGy from γ ray source where the y/b ratio of BSNDy2 increase by increasing exposure to gamma doses and were >1. In addition, electrical conductivity at different temperatures was investigated as the BSNDy2 sample gave the highest conductivity and decreased by BSNDy4. Moreover, shielding parameters such as the tenth value layer, half value layer, mean free path and mass attenuation coefficient values were calculated at different gamma-ray energies via the Phy-X program, showing the highest values for MAC, Z eff , N eff, and C eff for BSNDy4 sample. The findings showed that adding Dy 2 O 3 to the glass gave a fortified shielding character. [ABSTRACT FROM AUTHOR]

Bioactive borosilicate glasses having weight composition (74-X) SiO2, 16 Na2O, 10 B2O3 and (X) V2O5 (wt%), where (X = 0, 0.1, 0.3, 0.5, 1, 2.5, 4 wt %) were synthesized using the conventional melting procedure. Bioactive glass samples were melted in a platinum crucible of 50 ml capacity at 1400 °C in the globular furnace with air as the furnace atmosphere and kept hold for 2 h. These glasses were characterised and tested by using several experiment techniques like XRD, FTIR, SEM and EDX. The bioactivity of the borosilicate samples was determined by submerging them in simulated body fluid (SBF) for different time intervals. The developed hydroxy apatite (HA) was identified by FTIR, XRD, SEM and EDX technique. The obtained results demonstrate that the in-vitro bioactivity of the samples increases with the increase in V2O5 doping in samples. Various properties like density, compressive strength and electrical properties are determined. Physical and mechanical properties are improved after V2O5 doping. Electrical properties are improved after SBF doping, and the result shows the ion movement due to increased bioactivity. The in-vitro hemocompatibility and cellular compatibility on MG-63 cell lines were carried out. It was found that samples were compatible with human blood. Cellular proliferation is increased with increasing concentration of V2O5. However beyond 0.5% V2O5 doping the value of bioactivity decreases at higher concentrations of samples in culture media. [ABSTRACT FROM AUTHOR]

The immobilization of high-level nuclear waste (HLW) in glass waste matrices provides the key safety function of slowing down radionuclide emissions from an underground disposal site. This study examines the leaching behavior of two major elements, Na and Si, in HLW borosilicate glass simulated from waste of a 1000 MWe class pressurized water reactor (PWR) using response surface methodology and Box-Behnken Design. The design of the experiment was carried out considering three independent variables: the pH of the solution, the contact time, and the leaching temperature, leading to 17 leaching runs performed using the static product consistency test (PCT). The results of statistical analysis (ANOVA: analysis of variance) indicated that the effects of the individual variables and the interactions between them were statistically significant, and the relative consistency of the data further confirmed the model's applicability. Data obtained from the PCT experiments revealed that the leaching behavior of Na and Si in the evaluated waste glass exhibited similar behavior to previously researched glasses for each condition tested. [ABSTRACT FROM AUTHOR]

At present, doping of different alkaline-earth metal ions is mainly used to tune the emission peak of europium (Eu) ions in glasses. However, the optimization of Eu-doped glasses is hindered due to limited discussion on the relationship between local glass network structure, concentration of Eu ion dopants, and visible light emission by Eu ions. In this study,we prepared two series of borosilicate glasses doped with Eu ions, by varying the ratio of SiO2 to B2O3 and adjusting the concentration of Eu ion dopants to obtain cyan emission. The optical properties, structure, and differential scanning calorimetry (DSC) of the investigated glasses were systematically studied. With gradual increase in the content of SiO2, red shifting from 471 nm to 492 nm was observed under excitation at 410 nm, with the introduction of Eu2O3 also causing a redshift from 471 nm to 488 nm. The spectral results also revealed that under excitation at 410 nm all the glass samples exhibited cyan emission, with the optimal cyan peak at 492 nm (Si-45) and the strongest cyan emission at Eu-0.4 (480 nm). By adjusting the concentration ratios of Si to B in europium-doped borosilicate glass, it was observed that by altering the [SiO4] tetrahedra, [BO4] tetrahedra, and [BO3] triangles within the glass ultimately cyan emission can be achieved. By varying the doping concentration of Eu ion to change the degree of local Eu ion clustering in the glass system, cyan emission can be achieved by tuning the emission peak. [ABSTRACT FROM AUTHOR]

Based on municipal solid waste (MSW) ash as a main raw material, three novel borosilicate glasses with the composition of 70 waste + 20 borax + 10 Na2O + x ZrO2, where x = 0, 0.1 or 0.3 (wt. %),were prepared by the traditional melting-annealing technique. The prepared glasses were analyzed by EDX analysis, revealing the rich compositions of the prepared glasses correlated to the MSW ash used by 70 wt.% in preparing glasses. Some optical, chemical and radiation shielding properties of the prepared glasses were investigated. Either Zr addition or 80 kGy of gamma radiation revealed improvement of the glasses optical transmittance and chemical durability in neutral dis H2O, alkaline 0.1 N NaOH and acidic 0.1 N HCl leaching media for 70 days. Electron spin resonance (ESR) revealed the same spectra before and after irradiation, referring to the prevention of free radical formation by irradiation. The shielding parameters were measured by the experimental gamma spectroscopy (NaI detector) and the theoretical Phy-X/PSD software e.g., linear attenuation coefficients (LAC) and the findings revealed high unanimity among them at photon energies 0.662, 1.173 and 1.333 MeV. Another shielding parameters were also studied e.g., mass attenuation coefficients (MAC), effective atomic number (Zeff), effective electron density (Neff) and effective conductivity (Ceff). Presence of various metal oxides and the host trigonal BO3 and tetrahedral BO4 and SiO4 units, and ZrO2 provide the glasses compactness and effectual stability against ionizing irradiation. The prepared borosilicate glasses have highly strong and compacted structures that can inhibit the passage of radiation photons, because of the variety of many glass network formers, intermediates and modifiers present in the used waste ash. The results indicate the highly economic benefit of the prepared glasses, where the useless MSW ash are used mainly by 70 wt.% to produce effective borosilicate glass systems for promising radiation shielding purposes, especially 0.3 Zr borosilicate glass that has the best radiation shielding properties. [ABSTRACT FROM AUTHOR]

Lanthanide borosilicate glasses containing Pu and the nonradioactive analog element Ce were subjects of an x-ray absorption spectroscopy investigation to quantify the +3/+4 ratio of these redox-sensitive elements. The data show that the dominant oxidation states are +4 for Pu and +3 for Ce. The data also indicate that the reductive potential of glasses can be quantified from a solution chemistry method adapted to glass chemistry, although allowances must be made for glass composition. These data can therefore be used to formulate glass compositions and processing schedules that lead to a controlled oxidation state of Pu in melts. Furthermore, the data show that Ce is a poor analog for Pu behavior in melts and that the suitability of surrogates can be assessed by the evaluation approach presented here. The method demonstrated in this paper can be used to estimate the oxidation states of a range of multi-valent elements as functions of temperature and composition with data from only a single redox couple.

Evaluating the corrosion behavior of borosilicate glass after irradiation holds vital importance for the safe geological disposal of high‐level radioactive waste. This study examined the leaching properties of three kinds of sodium‐borosilicate (RNa2O‒B2O3‒KSiO2, denoted as "NBS") glasses with the same R but varying K under 5 MeV Xe‐ion radiation to decipher the correlation between the corrosion mechanism and glass composition. After Xe‐ion radiation, an increase in [BO3] units was observed, indicative of the glass network depolymerization. Irradiated glasses exhibited a more significant change in [BO3] units over the leaching time compared to their pristine counterparts. There is a strong correlation between the initial dissolution rates of pristine glasses, the K value, and the proportion of Na. Additionally, the initial Si dissolution rate of the NBS glasses has been accelerated by heavy ion irradiation. For the same R value over the glass series, the initial Si dissolution rates in ternary borosilicate glasses change at similar rates after irradiation. This study concluded that the variation trend in the initial dissolution rate of Si and Na differs under ion radiation. [ABSTRACT FROM AUTHOR]

The paper considers wear-free friction of ShKh-15 (ShKh) steel balls on the surface of quartz glass (QG) and borosilicate glass (BG) vessels in organic liquids and water. It is shown that it is impossible to accurately predict which material will wear out faster: hard or soft, ball or substrate. The highest correlation between the wear of coupling friction surfaces is found for balls and the total wear of working bodies (r ≈ 1). In the group of glass balls, the balls wear out more often (19 out of 21 tests) than in the group of steel balls (5 out of 9 tests). Wearless friction is more often observed in coupled pairs BG/ShKh (5 cases) than in pairs QG/ShKh (1 case). Coupling surfaces containing only one terminal SiOH group do not provide wear-free boundary friction. The usefulness of the work is in the fact that the results of studies of wear-free friction obtained for the ShKh/H2O pair can find practical application in the creation of bearings and large human joints. [ABSTRACT FROM AUTHOR]

The development of matrix with high capacity and stability immobilization of nuclear waste is highly desirable. Herein, new type of zircon-based borosilicate glass-ceramics (ZBGC) with high immobilization capacity and excellent aqueous stability was prepared and applied to immobilize simulated trivalent actinide (Nd). The effects of Nd doping and sintering temperature on the microstructure and phase composition of the obtained ZBGC were researched. The experimental suggested that high ZrSiO 4 formation rate (97.49 wt%) was obtained by tuning the Nd content and sintering temperature. The record high immobilization capacity of Nd in ZGBC (18 at%) was achieved owing to the synergistic effect between the crystal lattice and glass network immobilization. Additionally, the obtained Nd-doped ZBGC exhibited excellent aqueous stability (∼10−6 g m−2 d−1) due to the high compactness. The results demonstrated that ZBGC with high immobilization capacity and aqueous stability could be potential matrix for actinides immobilization. [ABSTRACT FROM AUTHOR]

This study demonstrates the significant impact of gallium ions on the local structure and physical, optical, and biological properties of borosilicate glasses. The glass composition, denoted as BSCZG, with the formula (50B2O3–5SiO2–15ZnO–(30-x)CaO–xGa2O3), where 0 ≤ x ≤ 20 mol%, was synthesized using the melt quenching technique. X-ray diffraction (XRD) patterns confirmed the amorphous nature of the BSCZG samples, presenting a broad hump. Analysis of the attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) results revealed the transformation of BO4 units into BO3 units, accompanied by generating non-bridging oxygens (NBOs) with increasing Ga2O3 content. As Ga2O3 content increased from 0 to 20 mol%, the experimental density (ρexp) and molar volume (Vm) of BSCZG glasses also increased, shifting from 2.70 to 3.14 g cm−3 and from 24.66 to 29.58 cm3 mol−1, respectively were also observed. This increment in Vm can be attributed to the rise in NBOs. Furthermore, an inverse relationship was observed between the optical band gap (Eopt) and optical band tail energy (EU); Eopt decreased from 3.27 to 3.08 eV, while EU increased from 0.20 to 0.25 eV with the Ga2O3 content rising from 0 to 20 mol%. The refractive index (n) of BSCZG glasses also increased from 1.52 to 1.57 as Ga2O3 content increased. Additionally, XRD patterns and ATR-FTIR spectra of BSCZG confirmed the formation of hydroxyapatite (HA) following assessment in simulated body fluid (SBF) for 3, 7, and 14 days. Protein adsorption in phosphate-buffered saline (PBS), cell viability (MTT) assays using Vero cells, and immersion in SBF were conducted to assess the bioactivity of the prepared samples. The results indicated that gallium ions containing borosilicate glasses exhibited significantly higher degradation rates than the Ga-free glass sample. Despite increased chemical durability, the substituted glasses displayed a favorable in vitro bioactive response. SBF results suggested that BSCZG glasses were more likely to contain higher concentrations of HA due to the elevated content of Ga ions. In conclusion, borosilicate glasses incorporating Ga3+ ions demonstrate promising effects for both optical and biomedical applications. [ABSTRACT FROM AUTHOR]

TThe paper justifies great practical relevance of the problem of corrosion and erosion resistance of the refractories used as a structural element in direct electric heating furnaces intended for high-level waste vitrification. The list of the main promising materials is provided, as well as the algorithm of assessing their resistance to borosilicate melts during operation of electric furnaces. Corrosion tests of the refractory materials were carried out under static and dynamic conditions in low-melting borosilicate glass and in the melt of borosilicate glass containing simulated liquid high-level waste (HLW). The refractories that are most resistant to the glass melt under conditions of HLW solidification were identified. The results obtained will be useful for selecting the lining material for removable and small-size melters. [ABSTRACT FROM AUTHOR]

The supply consumption of ladle furnace slag (LFS) is a prominence of recent researches and is extensively considered. In this work LFS has the potential to be utilized as the main raw material for producing glass and glass-ceramics because of its chemical compositions similarities to the silicate glass materials. Three borosilicate glass samples were produced via melting – quenching technique. The three samples contained 10, 20, 30 wt % of slag waste materials, respectively. The second sample was heat treated at 625 °C, guiding by DTA studies, for 2, 6, 10, or 15 h. XRD studies showed traces precipitation of Ca(Mg,Al) (Si,Al) 2 O 6 (diopside), Sodium Aluminum Silicate (NaAlSiO 4), Sodium Aluminum Borate (Na 2 Al 2 B 2 O 7) and Clinoenstatite (MgSiO 3) phases. FTIR analysis demonstrated the same functional groups through glass and glass ceramics sample confirming that all prepared samples had the same structure. Ferrimagnetism property of a glass sample and its glass ceramic sample derivative was confirmed by vibrating sample magnetometer (VSM) analysis. Vickers microhardness and fracture toughness results indicated noticeable rising in toughness value and decreasing of hardness after using 100 g load by increasing slag percent in glass samples. The glass ceramic sample had little change, in hardness and toughness values, rather than its corresponding glass sample due to its lower crystallization behavior. The low dielectric constant values are very good indication for the availability of using these type of glass for electronic applications. X-ray photoelectron spectroscopy (XPS) studies indicate that manganese ions are found as MnO in both glass and glass ceramic samples. [ABSTRACT FROM AUTHOR]

A new method for molecular dynamics (MD) modeling of the glass structure using a crystal structural template is proposed. The template is based on the unit cell of the crystalline phase, whose composition is qualitatively similar to the modeled glass. Using this approach and multistage MD simulation, the model of the spatial structure of grade E borosilicate glass, reproducing its physicochemical characteristics, is obtained. The proposed method enables to model the glass structure using classical MD methods with greater productivity and stability. [ABSTRACT FROM AUTHOR]

This study explores the radiation shielding properties of an xGd2O3 – (60-x)ZnO–15B2O3–5Al2O3–20SiO2 glass system (x = 0—3 mol %) glass system using FLUKA and XCOM software. The glass system is interesting due to its potential applications in nuclear and medical settings, where effective radiation-shielding materials are crucial. The FLUKA Monte Carlo simulation package is utilized to model the interaction of gamma photons with the glass system. At the same time, the XCOM software calculates the macroscopic cross-sections based on their elemental composition. The investigation evaluates parameters such as attenuation coefficients, dose rates, neutron cross-section, and stopping power for different radiation sources and energies. Various configurations are analyzed by varying the Gd2O3 concentrations in the present glass system to optimize shielding effectiveness. The results refer to the high radiation shielding potential of gamma rays and neutrons for the present glassy materials compared to previously studied shielding materials. The present study offers valuable insights into the radiation shielding properties of the studied glass system, facilitating the design and development of efficient radiation shielding materials for practical implementation in nuclear and medical industries. [ABSTRACT FROM AUTHOR]

In this work, we fabricated a new series of borosilicate glass doped with different concentrations of Gd 2 O 3. Then the glass samples were converted to glass ceramics using heat treatment at 500 °C for 2 h, and then the temperature was raised to 700 °C for 3 h. The X-ray diffraction (XRD) affirmed the amorphous nature of glass samples and the crystalline phase of glass-ceramic samples, which is related to SiO 2 (cristobalite). The Fourier transform infrared displayed many peaks related to functional groups for B 2 O 3 and SiO 2 , with a slight difference between glass and glass ceramic samples. The band gap (E g) for glass samples is 3.69, 3.64, 3.65, and 3.67 eV for BSTSGd0.5, BSTSGd1, BSTSGd1.5, and BSTSGd2, respectively. At the same time, the E g for glass ceramics is 3.61, 3.64, 3.64, and 3.64 eV for GCBSTSGd0.5, GCBSTSGd1, GCBSTSGd1.5, and GCBSTSGd2, respectively. The mechanical properties of glass samples align with packing density (V t) and compactness results, which indicated the superiority of BSTSGd1 glass samples over other glass systems. For example, the V t values are 0.674, 0.688, 0.683, and 0.680 for BSTSGd0.5, BSTSGD1, BSTSGd1.5, and BSTSGD2, respectively. On the other hand, we compared the linear attenuation coefficient (μ) between glass and glass ceramics which showed high compatibility due to the low difference in density for glass and glass ceramics. The μ values for BSTSGd0.5, BSTSGD1, BSTSGd1.5, and BSTSGD2 glasses at 0.600 are 0.088, 0.092, 0.093, and 0.095 cm−1, which showed enhancement when adding Gd 2 O 3 to the glass system. It can be concluded that adding Gd 2 O 3 slightly reduced the particle range for proton and alpha particles and enhanced the neutron and gamma shielding properties, which indicates the possibility of using the current samples in the radiation shielding field. [ABSTRACT FROM AUTHOR]

Fe 2 O 3 and TiO 2 were used as colorants in borosilicate glass, aimed to form amber-colored pharmaceutical glass. The status of the Fe and Ti ions and their influences on the glass structure were analyzed by FTIR, Raman and Mössbauer spectroscopic technique. The large addition of Fe 2 O 3 led to the decrease of connectivity of silica network and the increase of [BO 3 ]. TiO 2 showed even larger depolymerization effect. Fe3+ coordinated with the bridging oxygen in [SiO 4 ] increasing the aggregation of silica network and the [Fe2+O 6 ] filled the voids of glass network. Both types of iron ions helped to restrain the mobility of Na+ and improved the water resistance of the glass, while TiO 2 as a network modifier did the opposite. Either Fe 2 O 3 - or TiO 2 -containing samples exhibited enhanced UV-absorption capacity. The glass sample containing both Fe 2 O 3 and TiO 2 as colorants completely blocked the UV light, and exhibited the best water resistance. The results obtained herein enriched the understanding of the effects of colorants on borosilicate glasses and could provide useful information for the production of amber glasses used in pharmaceutical packing. [ABSTRACT FROM AUTHOR]

Here, we report on core–clad bioactive borosilicate fibers, that we have prepared both with round and rectangular cross‐section profile. The exposed approach, which relies on the stacking and drawing of glass slabs, demonstrates our ability to develop bioactive‐based glass fibers with tailored cross‐section profiles. Tens‐of‐meters‐long fibers were successfully drawn, although suffering from elevated losses in the case of the rectangular ones. The response of the fibers in simulated body fluid was studied for both geometries. We found that a round cladding can act as protective layer, tempering effects of the corrosion. We also noticed that rectangular fibers are more prone to degradation, the enhanced corrosion beginning from their sharp corners as they accumulated residual tensile stress during drawing. To the best of our knowledge, this is the first report on the effect of residual tensile stresses from surface tension deformations applied to the corrosion of rectangular fibers. As geometry plays a critical role on the biodegradation behavior of the fiberglass, we believe the enclosed results could lead to the design of fiber devices with tailored cross‐section profile in order to tune their rate of degradation on solely based geometrical effects. [ABSTRACT FROM AUTHOR]

We examine the impact of the glass network‐modifier cation field strength (CFS) on ion irradiation‐induced mechanical property changes in borosilicate (BS) glasses for the ternary M2O–B2O3–SiO2 systems with M = {Na, K, Rb} and the quaternary [0.5M(2)O–0.5Na2O]–B2O3–SiO2 systems with M = {Li, Na, K, Rb Mg, Ca, Sr, Ba}. 11B nuclear magnetic resonance (NMR) experiments on the as‐prepared BS glasses yielded the fractional population of four‐coordinated B species (B[4]) out of all {B[3], B[4]} groups in the glass network, along with the fraction of B[4]–O–Si linkages out of all B[4]–O–Si/B bonds. Both parameters correlated linearly with the (average) CFS of the M+ and/or {M(2)+, Na+} cations. Both the nanoindentation‐derived hardness and Young's modulus values of the glasses reduced upon their irradiation by Si2+ ions, with the property deterioration decreasing linearly with increasing Mz+ CFS, that is, for higher Mz+⋅⋅⋅O interaction strength. The irradiation damage of the glass network also increased linearly with the fraction of B[4]–O–Si linkages, which are the second weakest in the structure after the Mz+⋅⋅⋅O bonds. Our results underscore the advantages of employing BS glasses with high‐CFS cations for enhancing the radiation resistance for nuclear waste storage. [ABSTRACT FROM AUTHOR]

The glass samples (35-x)B2O3:35SiO2:12Na2O:7.9CaO:0.1Sb2O3:10BaO:xCr2O3 with a variation of Cr2O3 content were successfully fabricated and characterized for solid-state lighting material applications. The results showed the most suitable composition within the range of study at 0.02 mol% of Cr2O3. This composition gave higher reflection loss (RL), lower oxide polarizability, and lower molar refractivity. The Commission International de I'Eclairage (CIE) chromaticity coordinates confirmed a strong orange color emission. Hence, this suggests that the 0.02 mol% Cr2O3 glass is a good candidate and cost-effective for orange-emitting solid-state lighting material applications. This study will be a useful literature source for further development in this field. [ABSTRACT FROM AUTHOR]

We investigated the mixed alkali effect on the thermal properties and elastic response to temperature in the borosilicate glasses system with the composition of 70.65SiO2·21.09B2O3·1.88Al2O3·(6.3 8− x)Li2O·xNa2O glasses, where x = 0.00, 1.595, 3.19, 4.785, and 6.38. Except for the expected positive and negative deviations from linearity for the coefficients of thermal expansion, room temperature E and G, we observed a new mixed alkali effect on the response of elastic moduli to temperature. Fourier transform infrared spectra were obtained to elucidate the possible structural origin of the mixed alkali effects. This work provides a valuable insight into the structural and mechanical properties of mixed-alkali borosilicate glasses. [ABSTRACT FROM AUTHOR]

Relevance. The need to obtain experimental data on dependence of thermoviscosimetric properties of the examined borosilicate glasses on temperature, in order to solve the problem of developing a low-melting composition of borosilicate glass for a small-scale melter designed by Mayak Production Association. Aim. To get the most complete characterization of the glasses under study using thermoviscometric measurements. Methods. Mathematical modelling, simplex-lattice design. Results and conclusions. One of the most effective methods of experiment planning, which allows, with a relatively small number of experiments, obtaining a mathematical model reflecting the dependence of the studied property of the mixture on the content of components in it, is the simplex experiment planning method. To simplify the solution of such a task, a group or groups of components are usually distinguished, in which the ratio of the mass fraction of the components does not change. In this article, three groups of components are taken – simulators of high-level radioactive waste, sodium and boron oxides, and glass frit. The authors have identified the most promising area, where the mass fraction of glass frit is from 67.5 to 75%, the mass fraction of sodium and boron is from 25 to 32.5% and the mass fraction of high-level waste components is from 0 to 20%. The paper presents the results of thermoviscometric measurements of 15 melts of low-melting borosilicate glasses of different compositions at temperatures ranging from 700 to 1,200°C. Using simplex-based mathematical models of experiment planning, domains of dependence of thermoviscosimetric characteristics of glass melts on their compositions were created. The authors identified the compositions of glass melts that are found within the viscosity limits determined as allowable for glass melt discharge during operation of the removable small-scale melter of Mayak Production Association design.