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High entropy alloy nanopowders were successfully prepared by liquid-phase reduction methods and their applications were preliminarily discussed. The prepared high entropy alloy nanopowders consisted of FeNi alloy spherical powders and NiFeCoCrY alloy spherical powders with a particle size of about 100 nm. The powders have soft magnetic properties, the saturation magnetization field strength were up to 5000 Qe and the saturation magnetization strength Ms was about 17.3 emu/g. The powders have the excellent property of low high-frequency loss in the frequency range of 0.3–8.5 GHz. When the thickness of the powders coating was 5 mm, the powders showed excellent absorption performance in the Ku band; and when the thickness of the powders coating was 10 mm; the powders showed good wave-absorbing performance in the X band. The powders have good moulding, and the powders have large specific surface area, so that the magnetic powder core composites could be prepared under low pressure and without coating insulators, and the magnetic powder cores showed excellent frequency-constant magnetization and magnetic field-constant magnetization characteristics. In the frequency range of 1~100 KHz; the μm of the magnetic powder core heat-treated at 800 °C reached 359, the μe was about 4.6 and the change rate of μe with frequency was less than 1%, meanwhile; the magnetic powder core still maintains constant μe value under the action of the external magnetic field from 0 to 12,000 A/m. The high entropy alloy nanopowders have a broad application prospect in soft magnetic composites. [ABSTRACT FROM AUTHOR]

In this paper, a kind of zero valent FeNi alloy nano powder was coated on the surface of SrFe-MOF powder by a simple, efficient and pollution-free method, forming a core-shell type FeNi p @SrFe-MOF Magnetic powder (FSM). The FSM powder has a porous structure and a specific surface area of 9.16 ​m2/g. Under normal temperature and without changing the pH value of the wastewater, the FSM magnetic powder has an immediate and efficient removal effect on Congo Red (CR) dye wastewater. Furthermore, the powder has good cycling performance, with the CR removal rate remaining above 90% after five cycles. Also at room temperature and without changing the pH value of the wastewater, the FSM magnetic powder provides some immediate, efficient, and repeated use degradation of Cr(VI) wastewater. The FSM magnetic powder has good magnetic properties so that can be easily separated and recovered by magnetic field treatment, which solves the problem of efficient recovery of raw materials in wastewater treatment. FSM magnetic powder has broad application prospects for treating wastewater. In this paper, a kind of zero valent FeNi alloy nano powder was coated on the surface of SrFe-MOF powder by a simple, efficient and pollution-free method, forming a core-shell type FeNi p @SrFe-MOF Magnetic powder (FSM). Under normal temperature and without changing the pH value of the wastewater, the FSM magnetic powder has an immediate and efficient removal effect on Congo Red (CR) dye wastewater. Furthermore, the powder has good cycling performance, with the CR removal rate remaining above 90% after five cycles. Also at room temperature and without changing the pH value of the wastewater, the FSM magnetic powder provides some immediate, efficient, and repeated use degradation of Cr(VI) wastewater. The FSM magnetic powder has good magnetic properties so that can be easily separated and recovered by magnetic field treatment. [Display omitted] • FSM powder has an immediate and efficient removal effect on CR at room temperature and without changing the pH value of the wastewater. • FSM powder has some removal effect on Cr(VI) at room temperature and without changing the pH value of the wastewater. • FSM powder has good magnetic properties, which can be separated and recycled by magnetic field treatment. [ABSTRACT FROM AUTHOR]

• Soil microbial metabolism experienced C and P limitations in Poyang Lake wetland. • Flooding alleviated soil microbial metabolic limitations in the floodplain wetland. • Microbial C limitation was more sensitive to flooding changes than microbial P limitation. • Hydrological regime was the most important driver for soil microbial metabolism. Soil microbial metabolic limitations influence the equilibrium between microbial metabolic requirements and the accessibility of soil substrates and nutrients. Although extensive research has examined the effects of hydrological regime changes on soil microbial activity and community structures, our understanding of their effects on soil microbial metabolic limitations remains inadequate. In this study, we quantified and evaluated soil microbial metabolic limitations along a flooding duration (FD) gradient over a three-year period in the Poyang Lake wetland, China, using vector analysis of extracellular enzyme stoichiometry. Our results revealed that the lengths and angles of the vector analyses ranged from 1.32 to 1.58 and 56.82° to 65.19°, respectively, across all samples, indicating that soil microbial metabolism was primarily limited by C and P. Both the vector length and angle showed negative correlations with FD, suggesting that microbial C and P limitations significantly decreased with increasing FD. Flooding regime primarily affected microbial C and P limitations through direct effects, as well as indirect effects resulting from plant features (e.g., plant community diversity, biomass, and nutrient properties) and soil nutrient ratios. Among hydrological, vegetational, and edaphic variables, flooding was the dominant driver of microbial C and P limitations. Overall, our research highlights the importance of hydrological regimes in regulating soil microbial metabolic limitations and provides valuable perspectives for understanding and predicting soil C and nutrient cycling in floodplain wetlands. [ABSTRACT FROM AUTHOR]

• Fe 78-x Si 13 B 9 Y x alloy powders with excellent absorbing properties were prepared. • The mechanism of yttrium's influence on absorbing performance was explored. • The minimum interference thickness at 0.3 GHz decreased by 56.5%. • The performances were due to synergistic effects of components and structure. In this study, the effect of rare earth Y on the microwave absorbing properties of the powders was studied, directing against low electromagnetic loss (tanδ) and low dielectric constant of Fe 78 Si 13 B 9 alloy powders in the frequency band of 0.3–3 GHz. The results showed that when Y content is less than 2 at%, Y solid dissolves in dendrite gap of α-Fe, forming interstitial solid solution. With the increase of Y content, the permeability and dielectric constant of Fe 78-x Si 13 B 9 Y x alloy powders increase, especially the dielectric loss and magnetic loss increase significantly. Fe 76 Si 13 B 9 Y 2 alloy powders have excellent absorbing properties. When the frequency is 0.3 GHz and 1 GHz, the loss tangent value of that is as high as 5.22 and 2.42 respectively, and the minimum interference thickness is reduced to 11.81 mm and 5.20 mm, which is 45% of that of Fe 78 Si 13 B 9 alloy powders. Fe 76 Si 13 B 9 Y 2 alloy powders has excellent electromagnetic loss absorption and interference absorption properties at the same time. [ABSTRACT FROM AUTHOR]