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The 7000 series (Al-Zn-Mg-Cu) high-strength aluminum alloy is one of the highest strength aluminum alloy series.Stress corrosion cracking (SCC) is a key factor affecting its service safety and stability.In this paper, the anodic dissolution mechanism and hydrogen-induced cracking (HIC) mechanism of SCC were reviewed, and the effects of microstructure on SCC behavior and mechanism of the 7000 series aluminum alloy were summarized.Based on the effects of chemical composition of the alloy, heat treatment, pre-strain and surface treatment on SCC sensitivity, the effects of different microstructures on SCC behavior were discussed.The key research directions to reduce the SCC sensitivity of the 7000 series high-strength aluminum alloy were put forward:the microstructure of the alloy is reasonably regulated by optimizing the alloying elements, using new heat treatment processes and surface treatment technologies, to improve the service life of the alloy and better protect the aluminum material.

10Cr13Co13Mo5Ni3W1VE (S280) martensitic ultra-high-strength stainless steel under aging at 200, 400, and 500 ℃ was used as the research object. Through XRD, TEM, EBSD and other test methods, combined with electrochemical test methods and X-ray photoelectron spectroscopy (XPS) tests, the microstructure evolution of S280 and the structural composition and corrosion resistance of the passivation film were analyzed. The relationship between the stability characteristics of the passivation film and the microstructure of the material was studied.The results show that S280 steel aged at 500 ℃ has fine and dispersed precipitates with rich Cr and Mo elements distributed in martensite laths. As the aging temperature increases, there is no obvious precipitation of retained austenite and reverse transformed austenite.At the potential (0.1-0.85 V) of forming a passivation film, the S280 passivation film is a p-type semiconductor in a pH=8.5 borate buffer solution, having a double-layer film structure.The outer layer is composed of loose and porous Fe/Cr hydroxide, and the inner layer is composed of dense Cr/Fe oxide whose composition is mainly Cr2O3.The electrochemical impedance test combined with Mott-Schottky analysis proves that S280 steel aged at 200 ℃ has the best corrosion resistance. Its corrosion resistance is affected by the grain boundary characteristics and the element segregation caused by the precipitated phase.

The deep integration of technology and college sports professional training can effectively stimulate the enthusiasm of students for sports training and, to a certain extent, reduce the danger of professional training. This paper first introduces the virtual reality technology under information technology to build a virtual sports training framework, and through virtual sports training, can effectively realize the immersive training of participants. Secondly, we use LiDAR to obtain point cloud data for the virtual scene of college sports professional training and reconstruct the virtual scene using the Poisson surface 3D reconstruction algorithm. Based on the OpenPose human posture estimation algorithm, the training movements of students in the virtual scene are identified, which helps coaches to better formulate standardized training movements. Finally, to verify the effectiveness of the method given in this paper in college physical education training, a series of quantitative analyses was carried out. The results show that the training loss of the Poisson surface 3D reconstruction algorithm is about 0.087 after 180 rounds of iteration, the verification accuracy is about 87.62%, and the training loss of the OpenPose algorithm is about 0.04% when the number of iterations reaches about 130 times. After using VR technology to carry out professional training in sports, the score of students in the experimental group in terms of active learning interest is 4.487±0.324 points, which is about 1 point higher than that of the control group. Virtual reality technology can effectively promote the innovation and reform of sports professional training in colleges and universities, enhance the student’s interest in learning sports training, and provide a guarantee for improving students’ physical quality.

A key challenge to apply aqueous zinc metal batteries (AZMBs) as next‐generation energy storage device is to improve the rechargeability at high current densities, which is needed to circumvent slowly ion diffusion in anode and sluggish charge transfer of Zn2+. Herein, a zincophilic accordion array derived from MOF is developed as zinc host for simultaneously boosted ion diffusion and charge transfer. The designed host is prepared by etching and disproportionation reactions, the abundant zincophilic Sn sites with nano‐size uniform disperse on accordion arrays nanosheets (Sn‐AA). Then a composite Zn anode (Sn‐AA@Zn) is obtained by compacting Sn‐AA host with zinc power (Zn‐P). The Sn‐AA@Zn anode has an ultra‐low activation energy (37.1 kJ mol−1) and nucleation overpotential (10 mV), achieving fast charge transfer of Zinc deposition. In addition, the cycle life of the symmetric cell with Sn‐AA@Zn anode exceeds 13 000 cycles at 50 mA cm−2, which is 32 times than that of the Zn‐P anode. And the full cell with Sn‐AA@Zn anode and MnO2 cathode maintains a capacity of 122 mAh g−1 after 5000 cycles at 5 Ag−1. Hopefully, the 3D anode based on Sn‐AA@Zn accordion array and Zn‐P has significantly improved the rechargeability of AZMB at high current density. [ABSTRACT FROM AUTHOR]