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Palygorskite (Pal) shows great potential for physical, chemical and biological uses due to its colloidal, catalytic and adsorption properties. Pal mines, however, are facing the challenge of low-grade materials (5-15%), making it difficult to use Pal in emerging fields such as new materials, environmental protection and health. Therefore, there is an urgent need to develop an efficient method for separating and purifying Pal to obtain high purity levels. Hence, we have developed a dispersant-assisted rotating liquid film reactor separation strategy based on sodium hexametaphosphate as the dispersant. This strategy utilizes the double electron layer of Pal and the density difference between impurities to achieve effective disaggregation and purification of Pal bundles through the promotion of repulsive driving effects. Under optimal conditions, the purity of Pal can be increased from less than 10% to over 80%. This research presents a novel approach to the efficient refining of low-grade Pal. The crudely purified Pal's adsorption capacity for methylene blue increased from 84.2 to 256.4 mg g-1.

This review summarizes recent progress in the development of cobalt-based catalytic centers as the most potentially useful alternatives to noble metal-based electrocatalysts (Pt-, Ir-, and Ru-based) towards the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in acid and alkaline media. A series of cobalt-based high-performance electrocatalysts have been designed and synthesized including cobalt oxides/chalcogenides, Co–Nx/C, Co-layered double hydroxides (LDH), and Co–metal-organic frameworks (MOFs). The strategies of controllable synthesis, the structural properties, ligand effect, defects, oxygen vacancies, and support materials are thoroughly discussed as a function of the electrocatalytic performance of cobalt-based electrocatalysts. Finally, prospects for the design of novel, efficient cobalt-based materials, for large-scale application and opportunities, are encouraged.

While self-leadership has been widely studied, its specific impact on college students’ learning absorption lacks attention. This study addresses this gap by investigating the influence of self-leadership on learning absorption, focusing on students’ self-perceived influence. We used a three-dimensional model of self-leadership to assess its effect on learning absorption. Data were collected from college students via questionnaires, and descriptive statistics, correlation analysis, and analysis of variance were used to process the data. Multiple regression analysis helped determine the relationship between self-leadership and learning absorption. Our findings show a significant correlation between self-leadership and learning absorption. Each dimension of self-leadership—behavior-focused strategy, natural reward strategy, and constructive thinking model strategy—positively impacted learning absorption. Notably, the constructive thinking model strategy had the strongest effect, followed by the natural reward strategy, with behavior-focused strategy showing the least impact. These results highlight the vital role of self-leadership in college students’ learning. Implementing behavior-focused strategies can help clarify learning goals, while natural reward strategies can boost motivation and satisfaction. Additionally, fostering constructive thinking can enhance overall learning experiences. Ultimately, students who embody self-leadership characteristics tend to have better learning absorption, providing a strong foundation for personal and academic success.

The oxygen reduction reaction (ORR) plays a pivotal role in electrochemical energy conversion and chemical production. Two‐electron (2e−) charge transfer for oxygen reduction is considered a promising method for the on‐site production of hydrogen peroxide (H2O2), which requires electrocatalysts with high H2O2 selectivity and ORR activity. Noble metal alloys (e.g., Pt‐Hg and Pd‐Hg) have been prevalent materials of choice due to their desirable intrinsic activity, but their scarcity and high cost seriously hinder their widespread application in practice. Self‐doped heteroatomic carbon‐based electrocatalysts, derived from abundant and inexpensive biomass, have emerged as attractive candidates for on‐site H2O2 production. This review summarizes the fundamentals and recent advances in H2O2 production via 2e− ORR, including basic catalytic mechanisms, the influence of electrolyte pH and porous structure of catalysts, selectivity assessment methods, determination of the cumulative H2O2 concentration, development of biomass‐derived carbon‐based catalyst, and electrochemical device designs. Current challenges and proposed opportunities are also presented with an emphasis on large‐scale electrochemical H2O2 synthesis. Electrocatalysts based on self‐doped heteroatomic carbon, derived from abundant and cheap biomass, have emerged as attractive candidates for H2O2 production by electrocatalysis, and this process is on‐site, decentralized, and environmentally friendly. Importantly, the conversion of biomass waste into high‐value‐added electrocatalysts is beneficial to promote resource recycling and carbon fixation process.

Cognitive ability is an important aspect of children’s development, but there is still room for discussion about the impact of preschool education on children’s cognitive ability. Based on the data of China Urbanization and Children Development Survey (CUCDS) of Tsinghua University, this paper categorizes cognitive ability into Chinese language cognition and mathematical cognition. It is discovered that the impact of preschool education on children’s cognitive development differs depending on the cognitive ability and the length of time. In particular, preschool education has both short-term and long-term effects on children’s Chinese cognitive ability, while there is only a short-term effect on the development of children’s mathematical cognitive ability without long-term effect.

The design and development of highly efficient electrocatalysts for oxygen evolution reaction (OER) are critical for renewable energy generation. Ni‐based electrocatalysts are widely used in the water electrolysis process. In this work, heterostructure consisting of selenides and layered double hydroxides (LDH) named (Co, Ni)Se4@NiFe‐LDH, are prepared by an LDH‐based strategy, in which the electronic structure of Ni active sites is regulated by interfacial electron interaction. The (Co, Ni)Se4@NiFe‐LDH shows an optimized charge distribution of Ni sites and excellent catalytic activity. The effective charge modulation results in lowering the energy barrier of OOH* intermediate formation and adequate adsorption strength of the intermediates on Ni‐active sites, which improves the kinetics of OER. Specifically, the (Co, Ni)Se4@NiFe‐LDH only requires an overpotential of 237 mV to reach the current density of 10 mA cm−2 under alkaline conditions. The results of this work demonstrate that reasonable engineering of heterostructure is an effective strategy to improve the intrinsic property of OER electrocatalysts for water splitting. The engineering of double hydroxide heterostructures proves to be an effective strategy to tailor the electronic structure of the active sites, allowing efficient charge modulation towards the reduction of the energy barrier of formation of the OOH* intermediate. Thus, the OER process in alkaline medium, at 10 mA cm−2, only requires an overpotential of 237 mV.

Coupling adsorption and in-situ Fenton-like oxidation process was developed for Methylene blue (MB) using refined iron-containing low-grade attapulgite (ATP) clay, and the removal mechanism was investigated. The MB was initially adsorbed on the porous ATPs, and then the enriched MB was removed by the H2O2-assisted Fenton-like oxidation with the iron-containing ATP catalyst. Under optimal conditions, the ATP powder exhibits the maximum removal efficiency of 100% with negligible iron leaching (1.5 mg L−1) and no sludge formation. Furthermore, polysulfone/ATP (PSF/ATP) pellets were fabricated through a water-induced phase separation process to construct a fixed-bed reactor (FBR) for continuous contaminant removal. For the first cycle, the maximum adsorption capacity was 15.5 L with an outlet MB concentration of 1.973 mg L−1 (< 2 mg L−1, GB4287-2012) using the PSF/ATP pellets containing 50.0 g of ATP powders, and the maximum Fenton-like oxidation capacity was 35.5 L with the outlet concentration of 0.831 mg L−1. After five cycles, the total treated volume of the MB solution was ca. 255 L, and the efficiency remained above 99%. After 10 h of continuous treatment towards practical resin industrial wastewater, the chemical oxygen demand (COD) removal efficiency was still measured at 83.05%, costing 0.398 $ m−3. These results demonstrate the practical applicability of iron-containing low-grade ATP clay for textile water treatment. Coupling adsorption and in-situ Fenton-like oxidation by iron-containing low-grade attapulgite (ATP) from powder to polysulfone/ATP pellets towards organic pollutant removal: From batch experiments to continuous operation. [Display omitted] •A coupling approach for adsorption and in-situ Fenton-like oxidation was developed.•Iron-containing low-grade attapulgite clay was used for organic pollutant removal.•Powder to pellet was investigated for batch experiment and continuous operation.•Practical resin industrial wastewater was removed in a continuous fixed-bed.

Previous results reported that SiCp (Silicon Carbide particles) particle doping proved to be effective in enhancing the wear performance of WE43 magnesium alloy. In this work, finite element simulation was employed to investigate the effect of SiCp particle shape on the mechanical behaviors of SiCp/WE43 magnesium matrix composites. SiCp particles underwent larger load internally and a smaller plastic deformation under tensile loading, leading to the enhanced strength and stiffness of the composites. Polygonal SiCp particles provided a better enhancement in strength for the composites than round SiCp particles, but the enhancement in stiffness was opposite. Meanwhile, the damage is likely to initiate at the interface between the matrix and particle, at the location of the highest stress concentration. This phenomenon was more prominent in polygonal particle-reinforced composites. These current findings provide a comprehensive understanding of the effect of SiCp particle shape on the mechanical behaviors of magnesium matrix composites.

Biofilm is bacterial population adherent to each other and to surfaces or interfaces, often enclosed by a matrix. Various biomolecules contribute to the establishment of biofilms, yet the process of building a biofilm is still under active investigation. Indole is known as a metabolite of amino acid tryptophan, which, however, has recently been proved to participate in various aspects of bacterial life including virulence induction, cell cycle regulation, acid resistance, and especially, signaling biofilm formation. Moreover, indole is also proposed to be a novel signal involved in quorum sensing, a bacterial cooperation behavior sometimes concerning the biofilm formation. Here the signaling role and molecular mechanism of indole on bacterial biofilm formation are reviewed, as well discussed is its relation to bacterial living adaptivity.

Magnesium silicate as a high-performance adsorption material has attracted increasing attention for the removal of organic dye pollution. Here, we prepared a series of magnesium silicate hydrates (MSH) in a hydrothermal route, and carefully investigated the corresponding adsorption behavior towards methylene blue (MB) as well as the effect of surface charge on adsorption capacity. The results show that surface charge plays a key role in the adsorption performance of MSH for MB, a negative surface charge density follows the increase of Si/Mg feeding ratio from 1.00 to 1.75, and furthermore the higher negative charge favors the improvement of the adsorption capacity. Among four investigated samples (MSH = 1.00, 1.25, 1.50, and 1.75), MSH-1.75 has the highest negative surface charge and shows the largest adsorption capacity for MB. For example, the equilibrium adsorption quantity is 307 mg·g−1 for MSH-1.75, which is 35% higher than that of 227 mg·g−1 for MSH-1.00. Besides, for MSH-1.75, the as-prepared sample with negative charge exhibits ca. 36% higher adsorption quantity compared to the sample at the zero point of charge (pHZPC). Furthermore, magnesium silicate hydrate material with Si/Mg feeding ratio = 1.75 demonstrates the promising removal efficiency of beyond 98% for methylene blue in 10 min, and the maximum adsorption capacity of 374 mg·g−1 calculated from the Langmuir isotherm model.