In order to solve the problem of poor stability of traditional electrolyte membrane in all solid state lithium battery, a preparation method of thermally crosslinkable polymer electrolyte membrane for all solid state lithium battery of electric vehicle was proposed. Using 2-mercapto benzoxazole, sodium 5-sulfonate dihydro-2-mercapto benzimidazole complex as raw materials, then using toluene and dimethylformamide as preparation reagents, using high-speed centrifuge, magnetic stirrers and other preparation instruments for the preparation of all solid state lithium battery can be thermocrosslinked polymer preparation, and using the thermocrosslinked polymer to prepare the electrolyte membrane. The performance of the electrolyte membrane prepared is verified by comparative experiments. The experimental results show that the electrolyte membrane prepared by this method has smaller ion exchange capacity and higher proton conductivity, indicating that the preparation method has better stability.
The objective is to explore the change of natural vibration characteristics and seismic performance of concrete filled steel tubular arch bridge（CFST） under ambient temperature. The study was carried out by means of mechanical analysis. Firstly, the self-vibration frequency of the super-stationary structure of the arch bridge under the influence of ambient temperature is calculated based on structural dynamics. The degree of influence of ambient temperature changes on the self-oscillation frequency of the bridge structure is also analysed. Secondly, the structural response of the arch bridge during ground shaking is analysed based on the time course analysis method and interpreted in relation to the material elastoplasticity, travelling wave effect and the interaction between the structure and the foundation. Then, the research object of the above-bearing steel pipe and concrete arch bridge is taken as the research object, and the finite element analysis software is used to simulate and test the effect of the steel pipe and concrete arch bridge under the influence of ambient temperature. The experimental results show that the temperature variation characteristics of the arch bridge materials affect the self-oscillation frequency, with the modulus of elasticity of the asphalt material being more affected by the temperature variation. The frequency changes drastically in low and high temperature environments, causing the vibration pattern of the arch bridge to change. The effect of ambient temperature on the vertical ground vibration response of the arch ribs is negligible, while the lateral and longitudinal ground vibration response of the arch ribs increases at low temperatures. The results provide a reference for the seismic design of similar CFSTs.
The magnetic permeability and power consumption of FeNiMo cores were studied at heat treatment temperatures ranging from 590 to 730 ℃ using aerosolized powder. The magnetic permeability of the cores increased from 110 to 161 with the increase of heat treatment temperature, and the power consumption decreased and then increased. The cores at 650 ℃ heat treatment temperature had the smallest power consumption of 488.2 mW/cm~3 under the test conditions of f=100 kHz and B m =100 mT. The loss separation shows that the proportion of eddy current loss to the total power loss increases with the increase of frequency f and flux density B m with the increase of heat treatment temperature, the hysteresis loss decreases continuously, and the hysteresis loss no longer changes significantly at 650 ℃; The eddy current loss rises when the heat treatment temperature reaches 730 ℃. This is caused by the destruction of the insulation layer between the particles inside the magnetic powder core due to the high heat treatment temperature.
A variety of different components of aluminum-lithium alloy powder were designed and prepared. The aluminum-lithium alloy powder is formed by Selective Laser Melting（SLM）, and the highly dense, crack-free self-developed Al-Mg-Li alloy forming parts were selected for heat treatment process research. The results show that the third generation of Al-Li-Cu alloy is very prone to micro-cracks in the process of rapid solidification of SLM, and the second generation of Al-Li-Mg alloy is more suitable for SLM, which can obtain highly dense, crack-free forming samples. SLM Al-Li-Mg alloy is aged and heat treated at 200 ℃, the reinforced phase is mainly δ′ phase, the aging period reaches the peak aging state for 48 h, and the aging time continues to be extended, and its mechanical properties have decreased.
Studying the mechanical properties and deformation mechanism of pipe jacking tunnel joint is great significance to investigate the hidden dangers of pipe jacking tunnel. ABAQUS software has professional data processing and analysis functions. ABAQUS software is used for modeling to form the bending stiffness model of socket joint of circular rigid jacking tunnel based on ABAQUS. Simulation experiments are carried out to study the factors affecting the mechanical properties of socket joints. The results show that the stress change of socket joint is less affected by the tensile speed of rubber seal ring and more affected by hardness. When studying the influence of steel casing on the bending stiffness of the joint, it is found that the bending moment increases with the increase of opening angle, the bending stiffness increases with the increase of the thickness of steel collar, and increases with the increase of the length of steel collar.
