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In the process of aircraft structure X-ray images evaluation，there are some problems such as inaccurate crack segmentation and difficult crack detection under complex background. An intelligent evaluation model （ELAN-Seg） for X-ray crack images of aircraft structures is proposed based on efficient layer aggregation network. The ELAN-Seg model is compared with the DeepLabv3+ model in the crack segmentation ability of the Xray images. Combined with image processing technology，the crack length of model segmentation is evaluated，and the model is verified by X-ray images acquired during aircraft strength test and field maintenance. The results show that the segmented minimum crack length is about 3 mm，the ELAN-Seg model is more accurate in crack segmentation of complex background X-ray images，and the crack detection rate is less than 3.8%. The proposed model has engineering applicability.

Heterogeneous catalysts promoting efficient production of reactive species and dynamically stabilized electron transfer mechanisms for peroxomonosulfates (PMS) still lack systematic investigation. Herein, a more stable magnetic layered double oxides (CFLDO/N‐C), was designed using self‐polymerization and high temperature carbonization of dopamine. The CFLDO/N‐C/PMS system effectively activated PMS to remove 99% (k = 0.737 min−1) of tetracycline (TC) within 10 min. The CFLDO/N‐C/PMS system exhibited favorable resistance to inorganic anions and natural organics, as well as satisfactory suitability for multiple pollutants. The magnetic properties of the catalyst facilitated the separation of catalysts from the liquid phase, resulting in excellent reproducibility and effectively reducing the leaching of metal ions. An electronic bridge was constructed between cobalt (the active platform of the catalyst) and PMS, inducing PMS to break the O–O bond to generate the active species. The combination of static analysis and dynamic evolution confirmed the effective adsorption of PMS on the catalyst surface as well as the strong radical‐assisted electron transfer process. Eventually, we further identified the sites where the reactive species attacked the TC and evaluated the toxicity of the intermediates. These findings offer innovative insights into the rapid degradation of pollutants achieved by transition metals in SR‐AOPs and its mechanistic elaboration. [ABSTRACT FROM AUTHOR]

It is of great importance to promote charge separation in photocatalysts for enhanced photocatalytic activity under visible light irradiation. In this work, a type-II heterostructured photocatalyst was constructed by compositing phosphorus-doped g-C3N4 (P-CN) and Rh-doped SrTiO3 (Rh-STO) via a thermal calcination treatment. A series of characterizations were conducted to investigate the structure of heterostructured P-CN/Rh-STO. It was found that Rh-STO interacted with in situ generated P atoms from the decomposition of P-CN during the calcination process, thus leading to the formation of heterojunction of P-CN/Rh-STO. Compared with the single component, i.e., P-CN or Rh-STO, the obtained P-CN/Rh-STO showed superior photocatalytic activity to that of both P-CN and Rh-STO due to the effective charge separation across the heterojunction between P-CN and Rh-STO. [ABSTRACT FROM AUTHOR]

As the proton exchange membrane fuel cell (PEMFC) is a nonlinear, time‐varying, multiple‐input multiple‐output system, an advanced controller with strong robustness and adaptability is required for controlling PEMFC stack temperature and achieve a high operation efficiency. In this paper, a data driven optimal controller is proposed for controlling the stack temperature, which is based on large‐scale deep reinforcement learning. In addition, a new deep reinforcement learning algorithm termed curriculum guidance strategy large‐scale dual‐delay deep deterministic policy gradient (CGS‐L4DPG) algorithm is proposed for this controller. The design of this algorithm introduces the concepts of the curriculum guidance strategy and imitation learning, and its inclusion improves the performance and robustness of the proposed controller. The simulation results show that, taking advantage of the high adaptability and robustness of CGS‐L4DPG algorithm, the proposed controller can more effectively control the PEMFC stack temperature than existing control algorithms. [ABSTRACT FROM AUTHOR]