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Anorthite-based glazes are highly valued in the ceramics industry for their ease of crystallization under fast-firing conditions and their ability to impart excellent mechanical and aesthetic properties. This study investigates the effects of P2O5 on the thermal properties, microstructure, microhardness, and optical characteristics of anorthite-based glazes. The results indicate that the addition of P2O5 led to a reduction in both the glass transition temperature and crystallization temperature of the glazes. Furthermore, the increased intensity of the exothermic peak associated with crystallization suggests a greater amount of crystal formation in the P2O5-added glazes. In all compositions, anorthite was identified as the dominant phase. Moreover, an increased P2O5 content resulted in a higher number of anorthite crystals, while concurrently reducing their size. Glazes with P2O5 addition exhibited higher hardness values compared to those without P2O5. This outcome is attributed to the enhanced crystallization of the anorthite phase, as confirmed by DTA, XRD, and SEM analyses. [ABSTRACT FROM AUTHOR]

Silicate glasses containing sodium, calcium, and phosphorus are known as bioactive glasses, which are utilized in the human body to support and fulfill living tissue functions. These glasses exhibit excellent physical and mechanical properties, making them suitable for radiation shielding applications. This study focuses on investigating the radiation absorption parameters of seven bioglasses. The densities of the samples were found to increase from 2.6383 to 3.2218 g/cm3 as the ZnO increased from 0.0 to 15 mol%. Also, the mass-attenuation-coefficient (i.e., MAC) was calculated via the Phys-X simulation code in the photonic-energy domain of 0.015–15.0 MeV, and the outcomes were compared with XCOM data. The computed MAC values have the following sequential order: MAC46MBG-0Zn < MAC65MBG-5Zn < MAC64MBG-7Zn < MAC60MBG-15Zn < MAC45MBG-4Zn < MAC44MBG-7Zn < MAC40MBG-15Zn. Other important parameters, such as the half- and tenth-value-layer (i.e., HVL, and TVL), mean-free-path (MFP), and effective-atomic-number (Zeff), were also determined. Among the bioactive-glasses studied, the bioglass encoded as 60MBG-15Zn, which contains uppermost amounts of silicate and zinc, had the lowest MFP, HVL, and TVL values but the highest Zeff values. Effective removal cross-section values (ΣR) were determined to assess the neutron safety effectiveness of the bio-glasses, and the results indicated that 60MBG-15Zn ([ZnO]/[SiO2] = 0.258) and 40MBG-15Zn ([ZnO]/[SiO2] = 0.375) had advanced neutron lessening character. The exposure- and adsorption-buildup factor (i.e., EBF and EABF) values were also calculated using the G-P least-square-fit model, which depends on the photon energy and MFP. The bioglasses with higher equivalent-atomic numbers were found to have the lowest EBF, and EABF values. Also, the calculated elastic-mechanical intrinsic of the bio-glasses, including the molar volume (Vm), which increased from 16.680 to 20.128, and the dissociation-energy (G), which varied from 56.012 to 63.771 kJ/cm3 were found to depend on ([ZnO]/[SiO2] molar ratio. [ABSTRACT FROM AUTHOR]

Expensive cellulase and complex detoxification procedures increase the cost of biomass lactic acid fermentation. Therefore, it is of great significance to develop a robust method to ferment lactic acid using biomass by avoiding cellulase and detoxification. This study demonstrates the advantage of combining mechanocatalytic P2O5 pre-treatment and strain domestication. We show that an enzyme-free mechanocatalytic saccharification process by combining mix-milling of P2O5 with biomass and successive hydrolysis produces a fermentable hydrolysate with much less inhibitory compounds than the hydrolysates obtained by conventional methods; only 5-HMF, furfural and acetic acid were detected in the biomass hydrolysate, and no phenolic inhibitors were detected. Pretreatment of biomass with P2O5 not only avoided cellulase, but also obtained less toxic hydrolysate. Furthermore, the Pediococcus pentosaceus strain gained superior inhibitor tolerance through domestication. It could tolerate 17.1 g/L acetic acid, 12.5 g/L 5-HMF, 11.9 g/L guaiacol and 11.5 g/L furfural and showed activity in decomposing furfural and 5-HMF for self-detoxification, allowing efficient lactic acid fermentation from biomass hydrolysate without detoxification. The lactic acid concentration and conversion rate fermented by domesticated bacteria were increased by 113.5% and 22.4%, respectively. In addition, the domesticated bacteria could utilize glucose and xylose simultaneously to produce lactic acid selectively. The combination of P2O5 pre-treatment and strain domestication to ferment lactic acid is applied to several biomass feedstocks, including corn stalk, corn stalk residue and rice husk residue. Lactic acid concentrations of 29.8 g/L, 31.1 g/L, and 46.2 g/L were produced from the hydrolysates of corn stalk, corn stalk residue and rice husk residue, respectively. [ABSTRACT FROM AUTHOR]

The effects of the P2O5 and CaF2 contents and the basicity on the viscosity of CaO–SiO2–Al2O3–La2O3 slag systems were investigated using the rotating cylinder method during the continuous cooling process. The structural characteristics of the quenched slag samples were clarified by Fourier transform infrared and Raman spectroscopies. The results showed that the slag viscosity and break temperature gradually increased with increasing P2O5 content from 0 and 2.5 to 5 wt% at each basicity of 0.87, 1.0 or 1.17; meanwhile, the viscosity increased as the P2O5 content increased at a greater level at low basicity. The addition of CaF2 obviously reduced the viscosity and break temperature of slag. The increase in the basicity from 0.87 and 1.0 to 1.17 decreased the viscosity of the slags under the present composition range, but raised the break temperature. The maximum viscosity reduction by the basicity occurred in the slag containing 5 wt% P2O5, while the minimum occurred in the slag containing 5 wt% CaF2. P2O5 acted as a network former in the molten slag and increased the polymerization of the silicate and phosphate complex anions, corresponding to an increase in the slag viscosity. CaF2 played a major role in the depolymerization of the silicate and phosphate complex anions in this study.Kindly check and confirm the edit made in the title.The title was no problem. [ABSTRACT FROM AUTHOR]

The effect of TiO 2 and P 2O 5 on the ferric/ferrous ratio in silicate melts was investigated in model silicate melts at air conditions in the temperature range 1,400–1,550 °C at 1-atm total pressure. The base composition of the anorthite–diopside eutectic composition was modified with 10 wt % Fe 2O 3 and variable amounts of TiO 2 (up to 30 wt %) or P 2O 5 (up to 20 wt %). Some compositions also contained higher SiO 2 concentrations to compare the role of SiO 2, TiO 2, and P 2O 5 on the Fe 3+/Fe 2+ ratio. The ferric/ferrous ratio in experimental glasses was analyzed using a wet chemical technique with colorimetric detection of ferrous iron. It is shown that at constant temperature, an increase in SiO 2, TiO 2, and P 2O 5 content results in a decrease in the ferric/ferrous ratio. The effects of TiO 2 and SiO 2 on the Fe 3+/Fe 2+ ratio was found to be almost identical. In contrast, adding P 2O 5 was found to decrease ferric/ferrous ratio much more effectively than adding silica. The results were compared with the predictions from the published empirical equations forecasting Fe 3+/Fe 2+ ratio. It was demonstrated that the effects of TiO 2 are minor but that the effects of P 2O 5 should be included in models to better describe ferric/ferrous ratio in phosphorus-bearing silicate melts. Based on our observations, the determination of the prevailing fO 2 in magmas from the Fe 3+/Fe 2+ ratio in natural glasses using empirical equations published so far is discussed critically. [ABSTRACT FROM AUTHOR]

Fluoroapatite containing glass-ceramics were prepared from Li2O-CaO-CaF2-P2O5-SiO2 system. The glass was melted at 1480°C for 1 h. The object of observation was the preparing crystal phase of fluoroapatite in amorphous glass matrix. The morphology of lithium disilicate glass-ceramics was studied by SEM. The crystal growth and thermal properties of fluoroapatite were studied by X-ray diffraction and DTA. The more the content of P2O5, the more the presence of fluoroapatite particles. SEM investigation clearly indicated the phase separation and formation of a primary crystalline phase of fluoroapatite in the studied glass-ceramics. DTA curves of the fluoroapatite samples exhibit exothermic effects in the temperature range 337-694°C depending on the composition of the materials. The position of exothermic peak for lithium disilicate on DTA curves moves with increasing specific surface towards lower temperatures which points on its preferential surface crystallization. As far as physical qualities are concerned, mainly color and gloss, the best qualities of all observed materials belong to glass-ceramics with 10% P2O5. [ABSTRACT FROM AUTHOR]