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Soft soil layers are characterized by high sensitivity, high compressibility, and low bearing capacity, making them prone to deformation and uneven settlement under external loads and vibrations. Based on the foundation pit project of the Mangzhou Tunnel in Zhuhai City, this study combines field monitoring and numerical simulation to analyze the horizontal displacement of diaphragm walls, surface settlement, and axial forces of lateral supports. The study aims to investigate the deformation development pattern of deep excavations in soft soil and the impact of passive zone reinforcement. The results show that the curve of the wall horizontal displacement exhibits a "spoon-shaped" pattern, with the maximum value occurring at around 1. 4 times the excavation depth of the pit; passive zone reinforcement reduces the maximum value of wall horizontal displacement by 33%. The surface settlement follows a "settlement trough" curve, with the maximum value occurring at a distance of 0. 3 times the excavation depth from the edge of the pit, and passive zone reinforcement limits the maximum surface settlement to less than 0. 1% of the excavation depth. Excavation of the soil rapidly increases the axial force of current support, but the installation of next layer support effectively reduces the growth rate of axial force of the previous support, and passive zone reinforcement reduces the maximum support axial force by 25%. It is proved that passive zone reinforcement is an effective measure for controlling deformation of deep excavations in soft soil. The findings of this study can provide valuable references for the construction and monitoring of deep excavations in soft soil. [ABSTRACT FROM AUTHOR]

Considering the high cost of cobalt, cobalt‐free lithium nickel oxide (LiNiO2), which has an extremely high theoretical specific capacity, has become attractive. However, its application is hampered by continuous irreversible phase changes, unstable interfaces, and particle pulverization. Herein, an ≈35 nm‐thick selenium (Se) coating is applied to modify LiNiO2 using a combination of solid‐phase mixing and low‐temperature sintering. After 300 cycles, the selenium‐coated LiNiO2 (Se–LNO) cathode exhibits unusually high capacity retention of 82.09% at a charge cutoff voltage of 4.3 V. Furthermore, the coating modification improves the rate performance of the cathode materials, which exhibit considerable specific capacities of 168.7 and 149.6 mAh g−1 at current densities of 2 and 5 C, respectively. The significantly enhanced electrochemical performance can be attributed to the ability of the Se coating to enhance the structural stability of the cathode materials by suppressing phase transitions, stabilizing the interface, enhancing the kinetic behavior of the electrode, and reducing particle pulverization. According to the findings of this study, manipulating the Se coating in cathodes may provide a viable path for lower‐cost and higher‐energy‐density Co‐free lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Sulfur cathode materials in lithium–sulfur chemistry suffer from poor electronic conductivity and shuttle of lithium polysulfides during charging and discharging. Serious shuttle effects and the sluggish redox reaction kinetics of polysulfides severely limit the development of lithium–sulfur batteries with high sulfur loading, impeding the practical process of lithium–sulfur batteries. Herein, a honeycomb73x02010;structured CoF2@C is introduced as a functional layer adhered to the separator, achieving rapid lithium‐ion transport, high catalytic activity, and suppressed shuttle effect simultaneously. As a result, the cell with CoF2‐modified separator presents satisfactory cycle stability with a capacity decay of 0.076% per cycle within 300 cycles at 1 C rate with the sulfur loading of 2.0 mg cm−2. A low‐capacity decay of 0.088% per cycle for 200 cycles at 0.2 C is also achieved with sulfur loading of 3.0 mg cm−2. In addition, a high‐capacity retention of 697.5 mA g−1 is achieved with sulfur loading of 4.0 mg cm−2 and the electrolyte volume/sulfur mass (E/S) ratio of 8 μL mg−1. [ABSTRACT FROM AUTHOR]

Prosapogenin A is a secondary saponin in Dioscorea zingiberensis, and it showed remarkable pharmacological effects. Due to very low content and lack of well-developed biotransformation, its preparation was not efficient and clean. This study aims to establish an eco-friendly strategy for preparation of Prosapogenin A from plant material. Physical separation was employed to recycle starch and cellulose, and then D101 resin and polyamide packed-bed column was incorporated for purification of total steroidal saponins (TSS). After these pretreatments, purity of TSS was largely increased to 83.2% with recovery at 87.6%, which was subjected to enzymatic hydrolysis. Optimized reaction system was constructed in 0.20 M HAc-NaAc buffer (pH4.2) containing cellulase/TSS (3:1, w/w), and the hydrolysis was performed at 53 °C for 6 h. Consequently, TSS was almost completely hydrolyzed to Prosapogenin A, while the highest yield reached 5.62%. The newly proposed approach is promising for efficient preparation of Prosapogenin A in industrial applications. [ABSTRACT FROM AUTHOR]