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Mixed‐valence europium ions‐activated phosphors have distinct advantages in color modulation, dynamic anti‐counterfeiting, and optical sensors. Nevertheless, it is still a challenge to obtain mixed‐valence europium ions in single compounds by facile self‐reduction. Herein, the crystal structure of a 3D hexagonal network formed by SiO4/AlO4 tetrahedra is demonstrated to play a significant role in the spontaneous reduction of Eu3+ to Eu2+ based on SrAl2Si2O8, Sr2SiO4, SrAl2O4 hosts. The crystal field theory and Judd‐Ofelt theory provide a deeper understanding of Eu2+ and Eu3+ luminescence behavior, namely, the low energy spectra of Eu2+ are more easily observed in crystal structure with high polarizability and octahedral coordination, whereas the spectra properties of Eu3+ are affected by the symmetry of local environment and crystal rigidity. For SrAl2Si2O8: 0.02Eu2+/Eu3+, multi‐mode thermometry is explored in terms of the luminescence intensity ratio (LIR) of Eu2+/Eu3+, luminescence intensity (LI) and full‐width at half maximum (FWHM) of Eu2+ with maximal relative sensitivity reaching 3.83% K−1. This study presents the first exploration of optical manometry based on the LIR mode of Eu2+/Eu3+ with excellent sensitivity (Sr = 18.13% GPa−1). This work not only provides a novel strategy for the design of mixed‐valence ions‐activated materials but also constructs promising optical thermometry, and manometry candidates. [ABSTRACT FROM AUTHOR]

Geological disasters in large alpine reservoirs primarily take the form of landslide occurrences and are predominantly induced by slope instability. Presently, risk monitoring and assessment strategies tend to prioritize sudden alerts overlooking progressive trajectories from the onset of creeping deformations within the slope to its critical state preceding landslides. Hence, analyzing landslide safety risks over time demonstrates a significant degree of hysteresis, highlighting the necessity for a comprehensive approach to risk assessment that encompasses both gradual and sudden precursors to landslide events. This study analyzes the factors affecting slope stability and establishes a slope evaluation indicator system that includes terrain morphology, meteorological conditions, the ecological environment, soil conditions, human activity, and external manifestation. It proposes a quantitative model for slope landslide risk assessment based on a fuzzy broad learning system, aiming to accurately assess slopes with different risk levels. The overall assessment accuracy rate reaches 92.08%. This multi-dimensional risk assessment model provides long-term monitoring of slope conditions and scientific guidance on landslide risk management and disaster prevention and mitigation on a long time scale for risky slopes in reservoir areas. [ABSTRACT FROM AUTHOR]

The effect of tempering temperature on the microstructure and intergranular corrosion property of 2205 duplex stainless steel (DSS2205) was determined using a boiling acid intergranular corrosion test (boiling 65% nitric acid and 50% sulfuric acid–ferric sulfate), an optical microscope, a transmission electron microscope, and a double-loop electrochemical potentiokinetic reactivation (DL-EPR) test. The results show that the ferrite content of the DSS2205 is about 50% in a specimen close to a solid solution state (1050 °C for 1 h, then water-quenched) when tempered at 675 °C–725 °C for 1 h. As the tempering temperature rises to 750 °C–800 °C for 1 h, the ferrite content drops gradually from 49% to 35%. M23C6, FeCr (σ phase), and Cr2N phases are precipitated when the specimen is tempered at 675°C–800 °C for 1 h. When the tempering temperature rises to 750 °C–800 °C for 1 h, the content and size of σ phase increase significantly. In the boiling acid intergranular corrosion test, when the specimen is tempered at 675 °C–725 °C for 1 h, the corrosion rate is higher than when it is tempered at 750 °C–800 °C for 1 h. In the DL-EPR test, when the specimen is tempered at 675 °C–800 °C for 1 h, the intergranular corrosion sensitivity rises gradually. External polarization is added during the DL-EPR test, and the test principle is different from that of the boiling acid intergranular corrosion test, resulting in a different sensitivity to intergranular corrosion compared to boiling acid intergranular corrosion. [ABSTRACT FROM AUTHOR]