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To improve the adsorption and reusability of polypropylene (PP) fiber membranes, the organically modified saponite (Sap@P(St-co-MMA)) was prepared by solution polymerization. Furthermore, PP-based nanocomposite fiber membranes with strong oil adsorption, thermal stability, and reusability were prepared via melt-blown technology. The increased specific surface area of PP-based nanocomposite fiber membranes (PP-1.5%) provided more active sites for the oil adsorption. Simultaneous rheology and Fourier transform infrared measurements tests showed that Sap@P(St-co-MMA) enhanced the crystallinity of PP matrix, promoted the regular arrangement of molecules, and improved the intermolecular interaction force, which was beneficial for the oil adsorption. The adsorption of PP-1.5% (1.5 wt% addition of Sap@P(St-co-MMA)) fiber membrane for xylene and kerosene reached a maximum of 15.84 and 22.84 g [g.sup.-1], respectively. In the treatment of coal tar wastewater, the removal rate of oil can reach 62.9%, and the removal rate can still reach 51.17% after five cycles of experiments. In summary, PP-1.5% fiber membrane does not produce secondary pollution to the environment, and is a kind of oil removal material with good application prospect. Highlights * PP-based nanocomposites fiber membrane with strong oil adsorption was prepared. * Organically modified saponite had strong heterogenous nucleation for PP matrix. * Sap@P(St-co-MMA) increased the specific surface area of PP-based fiber membrane. KEYWORDS adsorption behavior, organically modified saponite, poly (propylene) nanocomposites fiber membranes, reusability, 1 | INTRODUCTION In recent years, with the rapid development of various enterprises such as coal chemical industry, resulting in the increasing of oily wastewater as well as the frequent [...]

The environmental dynamics in coastal regions are inevitably influenced by fluctuations in sea levels and human interventions. Evidence derived from archeological site remains and sediment cores indicates that sea-level change has been the primary driving force behind the continuous relocation of human settlements since the Holocene epoch. However, the understanding of the Holocene land formation process and its relationship with human activities in the northern flank of the Yangtze River Delta remains limited. The Guoqing Temple, located in southwest Juegang and serving as a hub for sea salt production during the Sui and Tang Dynasties, was established in the Tang Dynasty and served as one of the pivotal points along the Maritime Silk Road. A sedimentary core was obtained in close to the Guoqing Temple, and the sedimentological and micropalaeontological data were analyzed to investigate the process of sedimentary evolution from marine to terrestrial environments, as well as the environmental factors facilitating the development of the salt industry. Analysis results explained that: Between 6360 and 1750 cal yr BP, the study area was situated in a shallow sea on the outermost periphery of the sandbank, with a maximum water depth of 20 m. After 1750 cal yr BP, it underwent a transition to a supratidal low-salinity shallow marsh environment that continued to be influenced by marine conditions. The climate in the study area is primarily influenced by the Asian monsoon: Before 3000 cal yr BP, the overall climatic conditions were characterized by warm and humid conditions; After 3000 cal yr BP, climate stability prevailed in the region. Meanwhile, due to the newly formed wetlands that facilitated extensive salt production, economic shifts toward southern regions, and reforms in salt laws during the Tang Dynasty, Juegang emerged as a flourishing commercial trade hub and a prosperous center for Buddhist culture. [ABSTRACT FROM AUTHOR]

In this study, dual-root soybean (Glycine max L. Merr.) plants, with one side nodulated and the other nonnodulated, were used as experimental materials. The nonnodulated lateral roots were treated with excessive nitrate (200 mg·L−1 nitrogen) for three days, followed by a three-day nitrate withdrawal, and then subjected to excessive nitrate again for another three days. Meanwhile, the nodulated side was continuously supplied with nitrogen-free nutrient solution. We measured the nitrogenase activity, nodule quantity, and concentrations of sucrose, starch, and soluble sugars, along with the microstructure of the nodules. By analyzing these data, we aim to provide theoretical insights into how indirect nitrate supply affects the nitrogen fixation capacity of nodules. The results demonstrated that indirect supply of nitrate to the soybean nodules reduced the nodule nitrogen fixation ability, which was manifested in the decrease in nodule dry weight, nodule number, and nitrogenase activity. The reason was found to be related to the decrease in carbon sources (sucrose, starch, and soluble sugar) allocated to the nodules. Further observation of the internal structure of the nodules found that the number of infected cells in the nodules decreased with the addition of nitrate, and increased with its withdrawal. However, the addition and withdrawal of nitrate did not change the effect of nitrate on the structure of infected cells around the nodules after the first addition of nitrate. These may be one of the important reasons why nitrate indirectly affects the activity of nitrogenase in nodules. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) magnetic materials with high critical temperatures (TC) and robust magnetic anisotropy energies (MAE) hold significant potential for spintronic applications. However, most of 2D magnetic materials are derived from the van der Waals (vdW) layered bulks, which greatly limits the synthesis of 2D magnetic materials. Here, 2D M3B4 (M = Cr, Mn, and Fe; B = Boron), derived from hexagonal and orthorhombic M3AlB4 phases by selectively etching Al layers, was studied for its structural stability, electronic structure, and magnetic properties. By utilizing ab initio calculations and Monte Carlo simulations, we found that the orthorhombic Cr3B4 shows ferromagnetic (FM) metal and possesses an in-plane magnetic easy axis, while the remaining hexagonal and orthorhombic M3B4 structures exhibit antiferromagnetic (AFM) metals with a magnetic easy axis which is perpendicular to the two-dimensional plane. The critical temperatures of these 2D M3B4 structures are found to be above the 130 K. Notably, the ort-Mn3B4 possesses highest TC (~600 K) and strongest MAE (~220 µeV/atom) among these borides-based 2D magnetic materials. Our findings reveal that the 2D M3B4 compounds exhibit much better resistance to deformation compared to M2B2 MBenes and other 2D magnetic materials. The combination of high critical temperature, robust MAE, and excellent mechanical properties makes 2D Mn3B4 monolayer exhibits a favorable potential for spintronic applications. Our research also sheds light on the magnetic coupling mechanism of 2D M3B4, providing valuable insights into its fundamental characteristics. IMPACT STATEMENT: Two-dimensional magnetic hexagonal and orthorhombic M3B4 compounds with significant stiffness to preserve their magnetic properties were discovered using DFT calculations and MC simulations. [ABSTRACT FROM AUTHOR]