Abstract: Biochar-based materials have emerged as a promising solution for addressing multiple environmental challenges through sustainable biomass utilization. Derived from agricultural and forestry waste via pyrolysis and hydrothermal carbonization, these carbon-rich substances exhibit exceptional adsorption capabilities due to their porous architecture and abundant surface functional groups. Recent advancements in modification techniques, particularly chemical activation and nanomaterial integration, have substantially enhanced their pollutant removal efficiency and structural stability. Practical applications demonstrate remarkable effectiveness in immobilizing heavy metal contaminants, degrading persistent organic pollutants, and restoring degraded soils through improved nutrient retention and microbial activity enhancement. The materials' dual functionality in carbon sequestration and waste valorization presents a cost-effective strategy for mitigating climate change impacts. However, scalability challenges persist in optimizing production parameters for diverse feedstock types while maintaining consistent quality. Long-term ecological impacts require thorough investigation regarding potential secondary contamination risks and soil ecosystem interactions. Future research directions should prioritize developing standardized characterization protocols, intelligent responsive materials for targeted remediation, and synergistic systems combining biochar with phytoremediation technologies. This comprehensive analysis underscores the need for interdisciplinary collaboration to bridge laboratory innovations with practical environmental engineering applications, ultimately contributing to sustainable circular economy models in ecological restoration. Read More

Abstract: Creep behavior in solid propellants, characterized by time-dependent deformation under constant load, critically impacts the structural integrity and operational safety of rocket motors. This paper reviews recent advancements in creep research across three dimensions: (1) Macro-meso characterization techniques, including innovative indentation methods and high-resolution micro-CT/SEM imaging, which elucidate damage evolution mechanisms such as pore nucleation and crack propagation; (2) Multi-factor influences, revealing temperature-stress synergies, filler-matrix interactions, aging effects, and loading-rate dependencies that govern creep dynamics; (3) Cross-material experimental progress, highlighting breakthroughs in cementitious materials (20% prediction accuracy improvement), soft matter rheology (80% testing acceleration), and polymer microstructure transitions. While current studies have established comprehensive creep databases and advanced constitutive modeling, challenges remain in understanding long-term damage accumulation and multi-physics coupling under extreme conditions. Future directions emphasize in-situ multi-scale monitoring, cross-scale computational frameworks, and AI-driven predictive models for next-generation creep-resistant materials. Read More

Abstract: The importance of the nonferrous metal connection technology has become increasingly prominent due to its increasing application of the nonferrous metals in aerospace, portable electronic products, new energy vehicles. Aluminum / nickel dissimilar metals were welded by micro-resistance spot welding, which can effectively reduce the formation of brittle intermetallic compounds between joints, so as to improve the performance of joint. Microstructure analysis and tensile shear tests were performed on the joints, influence of welding current on microstructure and properties of nugget were explored. The results suggest that with the increase of welding current, the tensile shear force of the welded joints could initially increased and then decreased. With the maximum tensile shear force reached 101.25 N at a welding current of 3.6 kA, a welding time of 130 ms and a welding pressure of 120 N. And there was almost no intermetallic compound in the joint. Read More

Abstract: This study investigates the effects of varying lime saturation factors (KH = 0.85, 0.87, 0.90, 0.92) on the mineral composition and hydration behavior of low-heat Portland cement (LHC) clinker, providing theoretical guidance for its industrial production. X-ray diffraction (XRD), scanning electron microscopy (SEM), and hydration heat tests were employed to analyze the phase composition, microstructure, and hydration characteristics of the clinker. The results indicate that as KH increases, the C₃S content rises while the C₂S content decreases, leading to a significant increase in hydration heat peak values and cumulative heat release, as well as enhanced compressive strength. When KH = 0.90, the 7-day hydration heat reaches 276.8 J/g, and the 28-day compressive strength is 43.5 MPa, meeting the GB/T 200-2017 standard for low-heat cement (≤260 J/g) while exhibiting excellent mechanical performance. Read More

Abstract: At request of the authors, this article has been retracted by Warwick Evans Publishing (WEP) in light of clear evidence that the results and conclusions are no longer valid. We thank the authors for notifying us so that the publication record can be amended accordingly. Retraction published: June 11, 2025. Read More