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Freeze–thaw cycles are frequently overlooked as a pivotal factor contributing to leakage and structural failures in clayey soil-impermeable barriers used in landfills or tailings repositories in regions subject to seasonal freezing. This investigation explores the recovery and residual strength properties of Jilin ball clay undergoing six freeze–thaw cycles, and assesses the pore structure characteristics through a series of nuclear magnetic resonance (NMR) tests. The results indicate that normal stress has a greater impact on peak recovery strength than dry density and rest periods. Cohesion increases earlier and more significantly during rest periods compared to internal friction angle. Although the pore diameter remains consistent within the micropores during the freeze–thaw cycles, the soil's structural integrity undergoes notable changes. The concluding analysis provides valuable insights for the construction and management of impermeable barriers in landfills or tailings repositories within seasonally frozen areas. [ABSTRACT FROM AUTHOR]

Currently, the treatment of miscellaneous fill foundations, composed of a mixture of domestic garbage, construction solid waste, and natural soil, presents a significant challenge in urban peripheral engineering construction. This paper discusses the application of vibrating rod compaction technology for foundation treatment in Xinjiang. It evaluates the effectiveness of cross-section vibrating rod compaction equipment in reinforcing fine-grained miscellaneous fill foundations. The study analyzes the impact of construction disturbances caused by the insertion of the vibrating rod, monitoring horizontal stresses at various depths. Both laboratory and field tests show significant improvements: soil dry density increased by 8% to 18%, porosity decreased by 10% to 23%, compression modulus increased by 22% to 246%, and compression coefficient decreased by 8% to 70%. Additionally, cohesion (C) and angle of friction (ɸ) saw increases ranging from 7 to 38% and 3% to 25%, respectively. Below a depth of 3 m, cone tip resistance exceeded 10 MPa, and sidewall friction resistance increased to over 100 kPa, surpassing pre-treatment values. The standard penetration test results doubled stroke length compared to pre-treatment, indicating a substantial improvement in foundation bearing capacity. Surface wave tests before and after treatment showed a 15% increase in wave velocity, reflecting a more compact soil structure. The vibrating rod compaction method is innovative, energy-efficient, environmentally friendly, and economically beneficial, holding great potential for future miscellaneous fill treatments. [ABSTRACT FROM AUTHOR]

The potential application of anode-less sodium metal batteries (ALSBs) is severely affected by the irreversible depletion of sodium ions. Cathode sodium compensation (SC) additive is an effective way for sodium supplement due to its simplicity and flexibility. However, developing SC additives with no toxicity, low cost, low sensitivity to air and humidity is still a huge challenge. In this work, we propose a low-cost, environmentally friendly and air-stable organic sodium salt as sodium reservoir to compensate sodium ion, thus improving the cycle stability of ALSBs. The capacity of ALSBs with N: P as low as 0.5:1 could maintain capacity retention of 91.3% after 100 cycles with this SC additive, while the cell without this SC additive would decline to almost zero after 10 cycles. The inexpensive price and ease of preparation also make it suitable for industrialization. This work provides a realistic SC approach for improving the cycling stability for ALSBs. [ABSTRACT FROM AUTHOR]

The effectiveness of national policies for air pollution control has been demonstrated, but the relative effectiveness of short-term emission reduction measures in comparison with national policies has not. Here we show that short-term abatement measures during important international events substantially reduced PM2.5 concentrations, but air quality rebounded to pre-event levels after the measures ceased. Long-term adherence to strict emission reduction policies led to successful decreases of 54% in PM2.5 concentrations in Beijing, and 23% in atmospheric nitrogen deposition in China from 2012 to 2020. Incentivized by "blue skies" type campaigns, economic development and reactive nitrogen pollution are quickly decoupled, showing that a combination of inspiring but aggressive short-term measures and effective but durable long-term policies delivers sustainable air quality improvement. However, increased ammonia concentrations, transboundary pollutant flows, and the complexity to achieving reduction targets under climate change scenarios, underscore the need for the synergistic control of multiple pollutants and inter-regional action. In response to the rebound of air pollution during large events in China, the authors propose that a combination of ambitious short-term measures and enduring long-term pollution control policies is a sustainable solution for improving air quality. [ABSTRACT FROM AUTHOR]

Jilin ball clay is commonly employed as a construction material for the cover layer of landfills. The differences in temperature between the outside and inside of landfill renders the internal structure and stability of cover layer susceptible to desiccation cracks. To examine this phenomenon, a series of wet–dry cyclic tests were conducted employing the digital image correlation technique. The investigation systematically explored various crack characteristics of Jilin ball clay, including cracking morphology, water evaporation rate, and crack development under different thicknesses and temperature conditions. The findings of the test demonstrate that elevated temperatures have a positive correlation with the acceleration of specimen evaporation rates, and augmenting the thickness of the specimen can effectively impede crack formation due to the compensatory effect of moisture migration on surface water loss. Furthermore, the maximum values of crack length are attained prior to the inflection point of the desiccation curve during each cycle, and this trend becomes more pronounced as the temperature increases. However, the regularities in the pattern of changes in the average width of cracks were comparatively weaker when influenced by variations in thickness and temperature. The impact of wet–dry cycles on cracking parameters was primarily concentrated on the initial and subsequent cycles. The test results provide reference values for the subsequent research of drying-induced crack growth in Jilin ball clay. [ABSTRACT FROM AUTHOR]

The objective of this study was to predict Ki-67 proliferation index of meningioma by using a nomogram based on clinical, radiomics, and deep transfer learning (DTL) features. A total of 318 cases were enrolled in the study. The clinical, radiomics, and DTL features were selected to construct models. The calculation of radiomics and DTL score was completed by using selected features and correlation coefficient. The deep transfer learning radiomics (DTLR) nomogram was constructed by selected clinical features, radiomics score, and DTL score. The area under the receiver operator characteristic curve (AUC) was calculated. The models were compared by Delong test of AUCs and decision curve analysis (DCA). The features of sex, size, and peritumoral edema were selected to construct clinical model. Seven radiomics features and 15 DTL features were selected. The AUCs of clinical, radiomics, DTL model, and DTLR nomogram were 0.746, 0.75, 0.717, and 0.779 respectively. DTLR nomogram had the highest AUC of 0.779 (95% CI 0.6643–0.8943) with an accuracy rate of 0.734, a sensitivity value of 0.719, and a specificity value of 0.75 in test set. There was no significant difference in AUCs among four models in Delong test. The DTLR nomogram had a larger net benefit than other models across all the threshold probability. The DTLR nomogram had a satisfactory performance in Ki-67 prediction and could be a new evaluation method of meningioma which would be useful in the clinical decision-making. [ABSTRACT FROM AUTHOR]