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Purpose This study aims to clarify the evolution law of stress field and fracture field during the mining process of inclined coal seam, to prevent the occurrence of roof burst water and impact ground pressure accident during the advancing process of working face. Design/methodology/approach The evolution law of stress-fracture field under different mining conditions of inclined coal seam was studied by using discrete element method and similar material simulation method. Findings The overburden stress at the lower end of the coal seam was mainly transmitted to the deep rock mass on the left side, and the overburden stress at the upper end was mainly transmitted to the floor direction. With the increase of the inclined length of the mining coal seam, the development of the fracture zone gradually evolves from the “irregular arch” form to the “transversely developed trapezoid” form. The development range of the fracture zone was always in the internal area of the stress concentration shell. Originality/value An original element of this paper is based on the condition that the dip angle of coal seam is 35°, and the evolution law of overburden stress-fracture field during the excavation of coal seam with different lengths was analyzed by UDEC numerical simulation software. The coupling relationship between stress shell and fracture field was proposed, and the development range of fracture zone was determined by stress. The value of this paper is to provide technical support and practical basis for the safety production of a mine working face.

Rechargeable AAIBs were assembled with AlCl3/LiTFSI solutions as electrolytes. The addition of an appropriate concentration of LiTFSI can effectively impede the HER activity and Al corrosion, leading to a highly reversible Al anode.

Aqueous sodium-ion batteries (ASIBs) promise particularly increased operational safety and lower manufacturing cost than the current state-of-the-art organic electrolyte-based lithium-ion batteries.

Composite materials have been widely used in aerospace manufacturing because of their low mass, high specific strength, high specific stiffness and good fatigue resistance. However, composite structures are susceptible to damage such as debonding and delamination due to various impacts, vibrations and other external loads. Therefore, it is crucial to regularly monitor composite structures in real-time during spacecraft service to ensure the safety and reliability of the structures. Ultrasonic guided wave is an effective means of monitoring the health of composite plate structures. Delamination, debonding and other damages of composite materials can be imaged and localized using ultrasonic guided wave signals and probabilistic imaging methods. However, due to the large damping of composite materials, the traditional probabilistic imaging method has the problem of low accuracy in damage localization. Therefore, in this paper, we propose a probabilistic imaging method based on a modified time reversal for damage localization and imaging of delamination damage. The proposed method was experimentally validated using a composite plate as a test piece and compared with the conventional method. A fully automated falling hammer impact tester was used to create low-velocity impact damage on specimens to compare the localization accuracy of the time-free reverse method and the modified time reversal method for delamination damage. The results show that the modified time reversal method can better localize and image the delamination damage of composite structures with higher localization accuracy and more sensitive to damage, which verifies the feasibility and accuracy of the method in the localization of debonding damage of composite structures.

Current induced spin–orbit torque (SOT) switching of magnetization is a promising technology for nonvolatile spintronic memory and logic applications. In this work, we systematically investigated the effect of Ta thickness on the magnetic properties, field-free switching and SOT efficiency in a ferromagnetically coupled Co/Ta/CoFeB trilayer with perpendicular magnetic anisotropy. We found that both the anisotropy field and coercivity increase with increasing Ta thickness from 0.15 nm to 0.4 nm. With further increase of Ta thickness to 0.5 nm, two-step switching is observed, indicating that the two magnetic layers are magnetically decoupled. Measurements of pulse-current induced magnetization switching and harmonic Hall voltages show that the critical switching current density increases while the field-free switching ratio and SOT efficiency decrease with increasing Ta thickness. Both the enhanced spin memory loss and reduced interlayer exchange coupling might be responsible for the β DL decrease as the Ta spacer thickness increases. The studied structure with the incorporation of a CoFeB layer is able to realize field-free switching in the strong ferromagnetic coupling region, which may contribute to the further development of magnetic tunnel junctions for better memory applications.

As an emerging post-lithium battery technology, aluminum ion batteries (AIBs) have the advantages of large Al reserves and high safety, and have great potential to be applied to power grid energy storage. But current graphite cathode materials are limited in charge storage capacity due to the formation of stage-4 graphite-intercalated compounds (GICs) in the fully charged state. Herein, we propose a new type of cathode materials for AIBs, namely polycyclic aromatic hydrocarbons (PAHs), which resemble graphite in terms of the large conjugated π bond, but do not form GICs in the charge process. Quantum chemistry calculations show that PAHs can bind AlCl4- through the interaction between the conjugated π bond in the PAHs and AlCl4-, forming on-plane interactions. The theoretical specific capacity of PAHs is negatively correlated with the number of benzene rings in the PAHs. Then, under the guidance of theoretical calculations, anthracene, a three-ring PAH, was evaluated as a cathode material for AIBs. Electrochemical measurements show that anthracene has a high specific capacity of 157 mAh g-1 (at 100 mA g-1 ) and still maintains a specific capacity of 130 mAh g-1 after 800 cycles. This work provides a feasible "theory guides practice" research model for the development of energy storage materials, and also provides a new class of promising cathode materials for AIBs.

The urgent need for large-scale, low-cost energy storage has driven a new wave of research focusing on innovative batteries. Due to the high capacity and the low-cost of elemental Al, aluminum-ion batteries (AIBs) are expected as promising candidates for future energy storage. However, further development of AIBs is restricted by the performance of existing carbon-based cathodes and metal chalcogenide cathode materials. In this work, we deposited polythiophene (Pth) on a graphene oxide (Pth@GO) composite and used it as an AIB cathode material. This Pth@GO composite possesses high exposure of Pth active sites, high conductivity, and high structure stability while providing a very high discharge capacity (up to 130 mAh g

LaB6 nanofilm is coated on the top surface of silicon nanopillars forming a field emission array (FEA). Such a structure will be referred to subsequently as a ‘LaB6 hat-coated Si-FEA’. The electron emission mechanism of the LaB6 hat-coated Si-FEA is analyzed by OPERA simulation software. It reveals that the electron emission mainly depends on the LaB6 film edge. Moreover, the LaB6 hat-coated Si-FEA sample is prepared by microsphere lithography, and the field emission properties are tested. The results show that when the anode voltage is 850 V, the field emission current density reaches 458 mA cm−2, which is in good agreement with the simulation results. This work demonstrates that the field emission cathodes with low cost, high integration and high current can be realized by using LaB6 as emitter material combined with microsphere lithography technology.

Controlling effective separation of carriers at the interface is a key element to realize highly efficient halogenated perovskite-based optoelectronic devices. Here, a comprehensive study of interfacial properties for CsPbBr

Co-firing coal slime in circulating fluidized bed (CFB) boilers is an effective method for utilizing coal slime, as industrial solid waste, with high water content, high viscosity, high ash content and low calorific value. In order to study the morphology and drying characteristics of coal slime dough injected into the furnace, this paper studied in detail the influence of compression degree and water content on the tensile force of coal slime dough. The results show that the degree of compression is positively correlated with the tensile force of coal slime dough, while, the water content is negatively correlated. A one-dimensional quadratic mathematical relationship between the tensile force of coal slime dough and the water content is established. At different feeding locations, i.e., at the top or middle of the boiler furnace, the breaking length of the coal slime dough was predicted. With top feeding, the length is 0.17 m, and that value for the middle feeding is about 0.15 m. Using the coupling model of the movement and drying of coal slime dough inside the furnace of the CFB boiler, the temperature change of the slime dough was calculated. The results showed that the surface temperature of coal slime dough rose rapidly during the drying process, then decreased slowly before it dived into the dense bed. When the furnace temperature is 900 °C and furnace height is about 38 m, the temperature of the slime surface can reach 200 °C at the highest.

Polythiophene (Pth) is a good candidate cathode material for aluminum ion battery (AIB) because of its lightness, safety, plasticity and flexibility. However, it always manifests inferior stability. Herein, a stable Pth-based cathode is realized through the anchoring effect between Pth and carboxyl. Pth with a thin film morphology is in situ synthesized on the surface of carboxylated carbon nanotubes (CNT-COOH). As a support, CNT-COOH not only alleviates the agglomeration of Pth that provides abundant transport channels for ions and electrons simultaneously, but also enhances the stability of Pth through the anchoring effect. As a result, the prepared Pth/CNT-COOH composite exhibits high discharge capacity (113 mAh g−1 at 1 A g−1), outstanding rate performance (95 mAh g−1 at 5 A g−1) and stable cycle stability (10,000 cycles with 0.001% decay per cycle). This work realizes a promising Pth-based AIBs with high capacity and long lifespan, which paves the way to the applications of organic materials in AIBs.

Due to the high theoretical volume specific capacity and mass specific capacity of aluminum-ion batteries, they can meet the needs of contemporary society for high-performance energy storage devices, and have attracted a lot of research strength. Cathode materials are a key issue limiting the development of aluminum-ion batteries. Herein, polythiophene was prepared on the surface of carbon microspheres by in-situ oxidative polymerization, resulting in polythiophene carbon microsphere composite materials. It exhibits excellent electrochemical performance, as a cathode material for aluminum-ion batteries, in terms of a high specific capacity (106 mAh g−1 at a current density of 1 A g−1), good stability (maintaining 58 % of initial capacity after 10000 cycles) and excellent rate performance (90 mAh g−1 at a high current density of 3.5 A g−1).

With the development of coastal industries, marine pollution has intensified, and more and more shellfish in marine areas have been polluted to varying degrees. People's health can be compromised when eating contaminated shellfish. In the actual purification process of the shellfish purification plant project, there is no in-depth exploration of the parameters of the purification pond. Based on supplementing the basic research for the development of the oyster purification industry at different temperatures, salinities, pH, ultraviolet lamp power, irradiation time, and water flow rate, we find the best environmental conditions are a temperature of 30 °C, a pH of 8, a salinity of 32%, an ultraviolet lamp illumination power of 9w, an ultraviolet lamp irradiation time of 12h, and a water body flow rate of 0.5m/s. We supplement basic research related to bioengineering in China. We hope that our results can provide reference for further research and contribute to the sustainable development of the oyster purification industry. Create economic benefits for society.