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In order to study the micro-vibration characteristics of satellite platform and the effect of micro-vibration on the payload in space,a six-dimensional disturbance force simulator is designed to simulate the micro-vibration in space. First,the theoretical modeling analysis of the six-dimensional disturbance force simulator was performed. Secondly,the structure design of the uniaxial actuator and simulator model were performed and the finite element simulation analysis was applied on the models.Finally,the uniaxial actuator modal test was carried out and the simulator perturbation force experiment was performed. The results show that the error between the modal test results and finite element simulation analysis results of the single axis actuator does not exceed 2. 46 %; the error between the experimental results of the six-dimensional disturbance force simulator and the results of the disturbance force theoretical analysis is within 5%. Therefore,the six-dimensional disturbance force simulator meets the design requirements.

In recent years, with the rapid development of the Internet, the promotion and application of TikTok and other short video APPs have greatly enriched people’s life and ways of leisure. Many enterprises pay attention to the value of short video marketing, and short videos, as a type of commodity, have been used for marketing. All of these have promoted the continuous growth of short video marketing mode. However, at present, some enterprises or businesses are not clear about the impact of short video marketing on consumers’ purchasing behavior, which to a certain extent affects the utilization of business resources and the sustainable and stable development of enterprises. This paper mainly analyzes the characteristics of short video marketing, studies the the influence factors of short video marketing on consumer purchasing behavior, and puts forward some effective suggestions. Conclusions can be drawn that short video marketing has the features of original content and a combination of online and offline. One influence factor of the consumer purchasing behavior is the short video marketing platform availability and function availability. Another one is the psychological distance between consumers and short video marketing. Moreover, in order to improve the short video marketing effects, it is essential to make the personalized marketing scheme based on consumer demands and improve the professional quality of short video bloggers. Additionally, there is a need to build a consumer value common trust and strengthen the short video content management. Last but not least, it is also important to focus on the interaction with consumers and organize more diversified promotional activities.

Due to their unique photoelectric properties, nontoxic tin‐based perovskites are emerging candidates for efficient near‐infrared LEDs. However, the facile oxidation of Sn2+ and the rapid crystallization rate of tin‐based perovskites result in suboptimal film quality, leading to inferior efficiencies of tin‐based perovskite light‐emitting diodes (Pero‐LEDs). In this study, we investigate the influence of commonly used solvents on the quality of the CsSnI3 films. Remarkably, DMSO exhibits a stronger interaction with SnI2, forming a stable intermediate phase of SnI2·3DMSO. This intermediate effectively inhibits the oxidation of Sn2+ and slows down the crystallization rate, bringing in lower defect state density and higher photoluminescence quantum yield of the prepared perovskite films. Consequently, the corresponding Pero‐LEDs achieve a maximum external quantum efficiency (EQE) of 5.6%, among the most efficient near‐infrared Pero‐LEDs. In addition, the device processes ultra‐low efficiency roll‐off and high reproducibility. Our research underscores the crucial role of solvent‐perovskite coordination in determining film quality. These findings offer valuable guidance for screening solvents to prepare highly efficient and stable tin‐based perovskites. [ABSTRACT FROM AUTHOR]

The theory of calculating the curvature interference limit line of the offset involute cylindrical worm drive based on the singular point condition on the enveloping surface is established. The tooth surface equations and the meshing function of the worm drive are derived. Based on the singular point condition that the normal vector of the enveloping surface is zero, the equation of the curvature interference limit line is obtained. By employing the resultant elimination method and the geometric construction, the existence of the solutions of the curvature interference limit line is determined, and the reasonable initial values for the iteration program are afforded. The numerical outcomes show that there is one meaningful curvature interference limit line on each flank of single tooth of the worm gear, which usually does not enter the worm gear tooth surface. Both flanks of the worm gear are all settled in the side of the limit line, the curvature interference does not happen on the worm gear tooth surface. The undercutting of the cutting engagement process generally does not happen. The results also reveal that the curvature interference limit line is closer to the addendum and heel of the face worm gear on the i flank, which has the greatest potential venture inflict the undercutting. [ABSTRACT FROM AUTHOR]

Under normal physiological conditions, reactive oxygen species (ROS) are produced through redox reactions as byproducts of respiratory and metabolic activities. However, due to various endogenous and exogenous factors, the body may produce excessive ROS, which leads to oxidative stress (OS). Numerous studies have shown that OS causes a variety of pathological changes in cells, including mitochondrial dysfunction, DNA damage, telomere shortening, lipid peroxidation, and protein oxidative modification, all of which can trigger apoptosis and senescence. OS also induces a variety of aging-related diseases, such as retinal disease, neurodegenerative disease, osteoarthritis, cardiovascular diseases, cancer, ovarian disease, and prostate disease. In this review, we aim to introduce the multiple internal and external triggers that mediate ROS levels in rodents and humans as well as the relationship between OS, aging, and aging-related diseases. Finally, we present a statistical analysis of effective antioxidant measures currently being developed and applied in the field of aging research. [ABSTRACT FROM AUTHOR]

Recently, lead‐free Sn‐based perovskite light‐emitting diodes (PeLEDs) have attracted wide attention due to their near‐infrared emission and environmental friendliness. However, desired Sn2+ is easily oxidized to Sn4+ in the crystallization process, resulting in defects and intrinsically p‐doped properties in the perovskite films. The uncontrollable oxidation affects the charge injection balance and radiative recombination, leading to poor device performance. Herein, a bi‐functional conductive molecular, 2,7‐bis(diphenylphosphoryl)‐9,9′‐spirobifluorene (SPPO13) with two P═O functional groups, is used to interact with perovskite to passivate defects and suppress the oxidation of Sn2+. Moreover, the SPPO13 modification layer inserted between the perovskite emitter and the electron transport layer can regulate the carrier injection and transport, thus promoting the charge balance. As a result, the high‐performance near‐infrared CsSnI3 PeLEDs with a record external quantum efficiency (EQE) of 6.60% and ultra‐low efficiency roll‐off are achieved. The work provides a novel approach to regulate defect passivation and charge transport for efficient Sn‐based PeLEDs. [ABSTRACT FROM AUTHOR]