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This paper aims to study the maglev force and vibration attenuation characteristics of quasi-zero stiffness cruciform maglev isolators (CMIs). The maglev force and stiffness of CMIs were analytically computed based on equivalent charge theory, and the transfer function of the system was conducted. The effects of magnet geometry parameters and air gap on the maglev force, stiffness, and vibration transmission characteristics of the CMI system were revealed through parametric analyses. With the increase in magnet length and width, the maximum value of maglev force increases, but the displacement range of near-zero stiffness, amplitude, and phase of the system gradually decrease. With the increase in magnet height, the displacement range of near-zero stiffness increases, while the variation in the amplitude and phase of the system has minimal impact. Meanwhile, in the Halbach array, the height variation of the magnet at different positions has different impacts on the magnetic force. As the air gap increases, the maximum value of maglev force decreases, but the amplitude and phase gradually increase, and the displacement range of near-zero stiffness first rises and then decreases. Finally, an experimental study was carried out to test the vibration attenuation characteristics of CMIs, in which sinusoidal excitation, hammer strike excitation, and random excitation were applied. [ABSTRACT FROM AUTHOR]

In this interview, Wang Shouren introduces and reviews the journey of his literary research on British literature, American literature, and world literature. In an academic career of almost 40 years, he is apt at applying the socio-historical approach to make nuanced contemplation on the complicated relationship between literature and life. Juxtaposing literature with its historical context, his studies illustrate the authors' insights into their life and time by relating literature to socio-historical factors. Wang Shouren's systematic study on the principles of literary realism brings new life to socio-historical criticism and predicates that literature creates cognitive as well as aesthetic values in its representation and construction of reality. Wang Shouren's research on foreign literature bridges the gap between China and the West, meanwhile, he insists on the Chinese standpoint and maintains his own subjectivity as a Chinese scholar. Through translating literature in English, editing foreign literary histories and encyclopedia entries, and publishing articles and monographs, he demonstrates a character of praxis which is nourished by Chinese culture and history, and makes significant contribution to constructing China's systematic body of knowledge regarding foreign literature. [ABSTRACT FROM AUTHOR]

Machining the micro/nano texture on the surface of the workpiece can effectively improve the surface bearing capacity of the friction pair,while reducing the friction coefficient,friction and wear.Through the research and development status of micro/nano texture,the key design parameters,processing methods,friction reduction mechanism and micro/nano texture combined with coating technology are comprehensively expounded.Among them,the shape,depth,aspect ratio and area ratio of the texture are important parameters which have an impact on the friction and wear; pulsed laser processing technology has the most development prospect in micro/nano texture processing technology;according to the different anti-friction mechanisms of texture under different lubrication conditions,it can be applied to many fields such as machining,biomedicine,etc;the combination of micro/nano texture and coating can improve the bonding force between the coating and the tool surface,thereby improving the cutting performance and anti-bonding wear performance of the tool.Finally,the problems and research prospects in the study of the texture of the friction pair surface and its influence on the tribological properties are pointed out.

The microstructure evolution, corrosion resistance, and wear resistance of Al–18Si–4 Mg–2Mn–0.5Fe–xCu (x = 0,1,2,3,4,5 wt%) alloys prepared by laser additive manufacturing (LAM) process are studied. It is found that the addition of Cu not only produces Cu‐rich strengthened phase, but also promotes the precipitation of the second phase. With the addition of Cu, the corrosion resistance of the alloy decreases, which is due to the increase of potential difference caused by the increase of the strengthening phase. The addition of Cu can effectively inhibit corrosion cracking. The hardness and wear resistance of the alloy increase with the increase of Cu content under the synergistic strengthening of the Q‐Al5Cu2Mg8Si6 phase and Al2Cu phase. When the Cu content is 3 wt%, the hardness and wear resistance of the alloy are the best. However, with the increase of Cu content, part of the Q phase is transformed into the Al2Cu phase; this synergistic strengthening effect is weakened, and the hardness and wear resistance of the alloy are reduced, but still higher than that of the alloy without Cu addition, which indicates that the addition of Cu can effectively improve the hardness and wear resistance of the alloy. [ABSTRACT FROM AUTHOR]

Using the method of ultrasonic dispersion and the mechanical ball grinding the graphene mixing in titanium aluminum substrate, pressed by cold pressing molding and vacuum hot-pressing sintering technology of titanium aluminium alloy self-lubricating composites reinforced preparation of graphene. Using scanning electron microscopy（SEM）and transmission electron microscopy（TEM） and energy spectrum analysis（EDS）on microstructure and mechanical properties of the self-lubricating composites were studied. The results showed that graphene in the uniform distribution of titanium alloy substrate and graphene not interface reaction of titanium aluminium alloy, composite material density is better. When the amount of graphene is 0.3 wt%,self-lubricating composite material yield strength increase from 469 MPa to 555 MPa. The hardness of the self-lubricating composite was 11% higher than that of matrix, up to 468 HV; with the increase of the content of graphene composite material hardness and yield strength increases gradually, while graphene content is 0.7 wt %, reached the maximum hardness and yield strength of the composite material.