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In this study, a rod-like heterogeneous Bi2S3/Sb2S3 was systematically engineered through a simple one-step hydrothermal method and subsequently used as an anode active material for sodium-ion batteries (SIBs). The Bi2S3/Sb2S3 heterostructure electrode exhibits a high initial discharge capacity of 972.2 mAh g−1 and maintains a reversible capacity of 369.4 mAh g−1 after 500 cycles at a current density of 1 A g−1. The outstanding electrochemical performance of the Bi2S3/Sb2S3 electrode can be attributed to the synergistic contributions of the high capacity of Sb2S3 and the excellent stability of Bi2S3. Simultaneously, the abundant heterogeneous phase boundaries formed by Bi2S3 and Sb2S3 provide stable reaction interfaces, better structural integrity, and enhanced Na+ reaction kinetics. This work presents an opportunity to develop heterogeneous Bi2S3/Sb2S3 anode materials with excellent properties, holding promise for potential applications in SIBs. [ABSTRACT FROM AUTHOR]

Polyoxymethylene (POM) fiber is a new type of reinforcement material developed in recent years, which provides a new way and choice for the modification and reinforcement of cement-based materials. In order to improve the application of POM in the construction field, fiber-reinforced cementitious materials were prepared using 6- and 12-mm POM fibers. The effects of at two lengths of POM fibers on fluidity, compressive strength, flexural strength, flexural toughness, and tensile strength of cement mortar were investigated, and the bonding interface between fibers and the cement mortar matrix was observed using scanning electron microscopy (SEM). The results show that the addition of POM fibers reduced the fluidity and 7-day compressive strength of cementitious composites, but had little effect on 28-day compressive strength. With the increase of POM fiber volume fraction and length, better flexural toughness and ultimate tensile strength can be obtained. When the POM fiber length was 12 mm and the volume fraction was 0.90%, the equivalent flexural strength and ultimate tensile strength of the POM fiber–reinforced cement-based composite (POM-FRCC) increased by 46.3% and 13.5%, respectively, compared with the control group. Microscopic analysis revealed that the POM fibers were tightly bonded to the cement mortar matrix, and the fibers had a severe surface scraping in the resistance to damage. [ABSTRACT FROM AUTHOR]

The development of advanced electrode materials for sodium-ion batteries (SIBs) is crucial for the progression of energy storage technologies. In this study, we successfully fabricated V5S8/CoS nanoparticles confined within self-supported carbon nanofibers (CNFs) using a facile electrospinning method followed by a sulfidation process. Extensive characterization of the resulting V5S8/CoS-CNFs revealed their unique structural attributes, featuring a one-dimensional nanofiber morphology with enhanced Na+ transport pathways. In addition, V5S8 and CoS are typical semiconductors and have greater compatibility at the interface, which can enhance the synergistic effect in the composite. These V5S8/CoS-CNFs exhibited a remarkable reversible capacity of 201 mAh g−1 even at a high current density of 5 A g−1, along with a stable cycling performance of 165 mAh g−1 after 300 cycles at 2 A g−1. The incorporation of both V5S8 and CoS within the nanofiber structure substantially enhanced the pseudocapacitance effect, thereby improving sodium storage capabilities. The exceptional electrochemical properties of the binder-free V5S8/CoS-CNFs anode can be attributed to its heterogeneous composition embedded within CNFs. This composition effectively boosts the rate of sodium ion diffusion by generating a built-in electric field (BEF) at the V5S8 and CoS interface, alleviating volume stress during charge–discharge processes and enhancing overall conductivity. Our findings underscore the potential of V5S8/CoS-CNFs as high-performance anode materials for SIBs, offering valuable insights into the design and development of advanced electrode materials for future energy storage applications. [ABSTRACT FROM AUTHOR]

Plant transpiration plays a crucial role in the water balance of forest stands and water yield in arid and semiarid ecosystems. However, our understanding of the characteristics and modeling of transpiration or sap flow of degraded plantations in vulnerable ecology areas is still limited. In this study, the sap flow velocity (SF) of Populus simonii under different categories of degradation (LD, lightly degraded; MD, moderately degraded; SD, seriously degraded) during the growing season in the water‐wind erosion crisscross region of the Chinese Loess Plateau was continuously monitored and estimated using the modified Jarvis‐Stewart (MJS), modified process‐based (MBTA) and multiple linear regression (MLR) models. We found that the daily SF of P. simonii under the three categories of degradation was significantly different (p < 0.05), and degradation degree was negatively correlated with SF. Soil water deficit significantly reduced SF (p < 0.05). Soil water conditions and P. simonii degradation change the peak time of SF rather than the startup time. Three models give good performance for simulating the daily SF of degraded P. simonii, especially the MJS model. The stress of vapour pressure deficit (VPD) on SF first decreases and then increases with increasing VPD, and the VPD threshold is LD < MD < SD. The results provide a valuable reference for revealing the causes of degradation and assessing the drought resistance of plantation ecosystems in water‐limited areas. [ABSTRACT FROM AUTHOR]