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Regarding the new type of centrifugal spinning electric spindle as the research object,the method of rigid-flexible coupling was used to build the dynamic model of electric spindle; On the basis of modern computer simulation technology,the system vibration characteristic analysis was finished by using the combining simulated technique of Adams and Ansys,get the forced vibration amplitude frequency,phase frequency characteristic,then the electric spindle structure was improved,and software verification on the improvement. Experimental results shows: the structure improvement practical and effective.

The CR22MnB5/DH1050 dissimilar high-strength steel in automotive crash beams was welded by the direct current pulse TIG welding method. The microstructure and mechanical properties of the joints under different post-weld tempering treatments were tested and analyzed. The present results had a certain effect on further improving the performance of high-strength welded joints to use in the auto structure. The result showed that the weld zone (WZ) of the as-weld joint basically consisted of lath martensite. With the increasing tempering temperature, the original lath martensite gradually transformed into tempered martensite and tempered sorbite, and the C-containing solid solution in α-Fe gradually decreases, increasing carbides and grain growth. The WZ had the highest hardness, and a soft zone existed in the heat-affected zone of all steels. After tempering treatments, the microhardness of welded joint decreased, and the hardness decreased obviously after tempering at 550 °C. After tempering at 250 °C, the tensile strength of the joint was reduced (about 7 MPa) compared with the base material (BM), and the elongation was increased by 0.27%. After tempering at 550 °C, the tensile strength of the joint decreased by 166 MPa compared with the BM, while the elongation increased by 4.8%. After tempering at 250 °C, the maximum bending load applied to the joint (516 N) decreased insignificantly compared to the as-weld joint (558 N), while the bending resistance of the specimen (438 N) decreased significantly after the high temperature at 550 °C. In addition, the electrochemical corrosion potential of the welded joint by tempering treatments was positively shifted and the corrosion resistance was improved. [ABSTRACT FROM AUTHOR]

The widespread popularity of digital technology has enabled the rapid dissemination of news. However, it has also led to the emergence of "fake news" and the development of a media ecosystem with serious prejudices. If early warnings about the source of fake news are received, this provides better outcomes in preventing its spread. Therefore, the issue of understanding and evaluating the credibility of media has received increasing attention. This work proposes a model of evaluating news media credibility called MiBeMC, which mimics the structure of human verification behavior in networks. Specifically, we first construct an intramodule information feature extractor to simulate the semantic analysis behavior of human information reading. Then, we design a similarity module to mimic the process of obtaining additional information. We also construct an aggregation module. This simulates human verification of correlated content. Finally, we apply regularized adversarial training strategy to train the MiBeMC model. The ablation study results demonstrate the effectiveness of MiBeMC. For the CLEF-task4 development and test dataset, the performance of the MiBeMC over state-of-the-art baseline methods is evaluated and found to be superior. [ABSTRACT FROM AUTHOR]

Lithium‐ion capacitors (LICs) are becoming important electrochemical energy storage systems due to their great potential to bridge the gap between supercapacitors and lithium‐ion batteries. However, capacity lopsidedness and low output voltage greatly hinder the realization of high‐energy‐density LICs. Herein, a strategy of balancing capacity towards fastest dynamics is proposed to enable high‐voltage LICs. Through electrochemical prelithiation of Nb2C to be 1.1 V with 165 mAh g−1, Nb2C // LiFePO4 LICs show a broadened potential window from 3.0 to 4.2 V and an according high energy density of 420 Wh kg−1. Moreover, the underlying mechanism between prelithiation and high voltage is disclosed by electrochemical dynamic analysis. Prelithiation declines the Nb2C anode potential that facilitates electron transmission in the interlayer of two‐dimensional Nb2C MXene. This effect induces small drive force for Li+ ions deposition and hence weakens the repulsive force from adsorbed ions on the electrode surface. Benefiting from even more Li+ ions deposition, a higher voltage is eventually delivered. In addition, prelithiation significantly increases Coulomb efficiency of the 1st cycle from 74% to 90%, which is crucial to commercial application of LICs. [ABSTRACT FROM AUTHOR]