Syntheses and surface engineering of composite anodes by coating thin-layer silicon on carbon cloth for lithium storage with high stability and performance

Silicon-flexible carbon composites can achieve binder-free application and solve the problem of silicon expansion during cycles. The effective loading and dispersion of silicon onto carbon play an important role in improving the performance of anode materials. Herein, surface engineering of the hole-opening process was successfully achieved before the deposition of silicon. This resulted in fine holes on the carbon cloth, increasing the specific surface area to provide abundant confined spaces for dispersing nano-silicon. A composite structure was formed and structurally optimized by depositing an ultra-thin silicon layer in the holes of mesoporous carbon fiber cloth (DTSi/CC), improving the conductivity of the material, increasing the migration rate of lithium ions, and inhibiting the volume expansion of the anode material during the cycles. At 100 mA g–1, the fabricated half-cells achieved a reversible capacity of 1457 mA h g–1 and retained 70.9% initial capacity after 100 cycles. Even when the current density was increased to 1.0 A g–1, they boasted a capacity of 1037 mA h g–1 and had 76.8% capacity retention after 500 cycles. Free of binders and conductive additives, the DTSi/CC composite was directly used as the anode, exhibiting superior properties with high reversible specific capacity, excellent cyclic performance, and good rate capability. This study provides a straightforward, effective route to obtain high-performance silicon-based anode materials for lithium-ion batteries

A Novel Searching Method Using Reinforcement Learning Scheme for Multi-UAVs in Unknown Environments

In this paper, the important topic of cooperative searches for multi-dynamic targets in unknown sea areas by unmanned aerial vehicles (UAVs) is studied based on a reinforcement learning (RL) algorithm. A novel multi-UAV sea area search map is established, in which models of the environment, UAV dynamics, target dynamics, and sensor detection are involved. Then, the search map is updated and extended using the concept of the territory awareness information map. Finally, according to the search efficiency function, a reward and punishment function is designed, and an RL method is used to generate a multi-UAV cooperative search path online. The simulation results show that the proposed algorithm could effectively perform the search task in the sea area with no prior information

Geological characteristics and potential evaluation of typical interlayer shale oil in the Ordos Basin: A case study of the Chang 7 Member of Well Ning228

The Chang 7 Member of the Ordos Basin has favorable shale oil resource potentiality. The exploration and development of sandstone interlayer shale oil in the Chang 7 Member has made substantial breakthroughs. The exploration and development potential of shale oil is huge, and will be a significant oil and gas alternative resource in the Changqing Oilfield in the future, but its related geological fundamental research is relatively weak. Based on the observation, description and systematic sampling of the centimeter-level core of the full core section of Chang 7 Member in Well Ning228, a series of experimental test analyses and identification outcomes indicated that Chang 7 Member primarily developed four rock types: Black shale, dark mudstone, siltstone and tuff. The overall conditions of source rocks in the Chang 7 member are superior, the organic carbon content of shale is high, and the hydrocarbon generation potential is large. The organic matter types are mainly type Ⅰ and type Ⅱ, which are in the low mature-mature stage, and the black shale has higher organic matter abundance. The main reservoir spaces of the Chang 7 Member are primary pores and secondary pores. Mud shale primarily develops organic pores and inorganic pores. Fine sandstone mainly develops residual intergranular pores, intragranular pores and intergranular pores. Tuff mainly develops intergranular pores and mineral intragranular pores. The overall oil-bearing property of the Chang 7 Member is good, but the mobility difference is large. The fluid mobility in sandstone and tuff is good, and the mobility inshale is poor. In short, fine anatomical analysis of typical interlayer shale oil provides favorable guidance for promoting the large-scale development of shale oil in the Ordos Basin