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Transition-metal selenides have been extensively studied as promising electrode materials for supercapacitors. Engineering amorphous/crystalline heterostructures is an effective strategy to improve rich active sites for accelerating redox reaction kinetics but still lacks exploration. In this study, an amorphous/crystalline heterostructure was designed and constructed by selenizing the self-sacrificial template NiMnS to generate amorphous Mn/polycrystalline Ni0.85Se–NiSe2 heterophase via the phase transformation from metal sulfide into metal selenide. The synergy of the complementary multi-components and amorphous/polycrystalline heterophase could enrich electron/ion-transport channels and expose abundant active sites, which accelerated electron/ion transfer and Faradaic reaction kinetics during charging/discharging. As expected, the optimal NiMnSe exhibited a high specific charge (1389.1 C g−1 at 1 A g−1), a good rate capability, and an excellent lifespan (88.9% retention). Moreover, the fabricated NiMnSe//activated carbon device achieved a long cycle life and energy density of 48.0 W h kg−1 at 800 W kg−1, shedding light on the potential for use in practical applications, such as electrochemical energy-storage devices. [ABSTRACT FROM AUTHOR]

In modern industrial production, many advanced manufacturing technologies are constantly developing with the progress of social sciences. Welding, as an indispensable manufacturing technology in industrial production, has received close attention from various industries. High frequency welding technology is needed in fields such as mechanical manufacturing, machine making in the food industry, and intelligent robot model making. High frequency welding is an important technical means in the production process of welded pipes, and the level of welding temperature has a significant impact on the quality of welded pipe welds. This article studied the shortcomings of traditional high-frequency welding, analyzed the application method of nonlinear finite element method in high-frequency welding, and analyzed the dynamic process of welding and its influencing factors. The finite element method formula is used to stabilize the value of three-dimensional (3D) temperature field. This work studied the temperature distribution of welded pipe welding, welded pipe materials, inside and outside of welded pipe, and temperature changes under different voltages. The experimental results showed that the error value between the simulation results of the 3D temperature field of high-frequency welding and the measured experimental results was about 4.3542°C, which was basically similar, indicating the effectiveness of the 3D temperature field simulation experiment. With the development of science and technology, high-frequency welding technology would continue to improve, and the quality of welded pipe welds would become better and better with the progress of technology. The improvement in quality promotes the development and progress of industry, and maintains the quality of machine manufacturing. The simulation experiment method of 3D temperature field has shortened the experimental time and reduced the experimental cost, providing a new reference for other temperature related experiments.

The encapsulation test of 0.1 mm thick SUS304 stainless steel with BNi-2 as the intermediate layer was carried out by using resistance spot brazing technology. The influence of technological parameters on the microstructure and mechanical properties of resistance spot brazing joint was analyzed, the element distribution and phase composition in the joint area were determined, and the air tightness of the joint was verified. The results show that the resistance spot brazing joint is composed of the brazing zone, the thermomechanical affected zone and the base material; With the increase of welding current and electrode pressure, the thickness of the brazing zone decreases and the dynamic recrystallization degree of the thermomechanical affected zone increases; The high cooling rate inhibits the element diffusion between the brazing joint and the base metal, the phases of the brazing joint are nickel based solid solution and dispersively distributed fine Cr2B and Ni3B particles, the maximum shear resistance of the joint is 118.3 N; The maximum load pressure of the package element reaches 0.53 MPa, which indicates that the resistance spot brazing joint of ultra-thin austenitic stainless steel has excellent air tightness.

Medical image colouring techniques enable to colourize grey‐scale medical images for assisting doctors in diagnosis. Benefiting from the non‐linear fitting ability of deep neural network, deep medical image colouring techniques have achieved remarkable results. However, existing methods are still facing content and structure feature leakage, unrealistic colouring and poor scale invariability. Thus, this paper, proposes a Transformer‐based medical image colouring algorithm with long‐term dependency to avoid feature leakage of coloured images. To be specific, this method employs two different Transformer encoders to generate and encode feature sequences for grey‐scale medical images and real human colour slice images, respectively. Then, a novel multi‐layer Transformer decoder is used to stylize grey‐scale map image features based on the real physical colour feature sequences. For colouring images at different scales, we implement content‐ aware positional encoding with scale invariance and propose style‐aware positional encoding strategy to take realistic and physical colour prior into account. Extensive experimental results indicate our method has achieved better colourization effects than recent state‐of‐the‐art medical image colourization methods. [ABSTRACT FROM AUTHOR]

A new expansion-continuous shear deformation technique was used to prepare the 6061 aluminum alloy sheet. The extrusion deformation behavior of 6061 aluminum alloy was discussed by the finite element simulation. The microstructure and mechanical properties of 6061 aluminum alloy were studied via the testing and analysis tools of electron back-scatter diffraction,tensile test and scanning electron microscope. The results show that the expansion-continuous shear deformation can coordinate the stability of metal flow velocity during the deformation process of the aluminum alloy. The severe plastic deformation can produce a large and uniform equivalent strain in the extrusion billet, which can effectively trigger continuous dynamic recrystallization, moreover, the orientation distribution of fine grains is scattered, which can effectively refine the grain and weaken the texture. After extrusion, 6061 aluminum alloy presents excellent mechanical properties, and the tensile strength and the elongation can reach up to 380 MPa and 21%, respectively. A large number of dimples emerge in the tensile fracture, which can be attributed to ductile fracture.

To achieve the dynamic allocation of multiple resources and improve the resource utilization with ensuring the queue stability, the paper proposes a joint resource optimization algorithm based on queue stability in wireless virtualized networks. Considering the cache resource constraints and different pricing mechanisms for each virtual operator, the algorithm allocates multiple virtual resources as a joint optimization problem, and establishes a utility function aiming at maximizing the profit of virtual operators. Secondly, based on the data volume, a distributed scheduling algorithm is designed to balance the optimality of the virtual network revenue and the stability of the system queue through Lyapunov stochastic optimization. Finally, the Lagrange duality theory is used to solve the model. The simulation results show that the proposed method can effectively improve the total average revenue of virtual network while guaranteeing the queue stability.

Dense heterogeneous network enhances spatial multiplexing by encrypting a small base station, for users in the small base station between the frequent switching problems. In this paper, a local clustering network architecture and handoff management mechanism based on local mobility is proposed. The 5G New Radio technology user connected-inactive state is introduced, and the discrete-time Markov transfer model is constructed. The cost of the handoff function evaluates the performance of the proposed mechanism. The simulation results show that the proposed handoff mechanism reduces the handoff consumption compared with the current handoff scheme, and effectively reduces the handoff delay.