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The long-term storage performance of energetic multilayer nanofilms is of great significance for their applications. In this paper, it is proposed to add a 10 nm Cu barrier layer between Al/CuO composite films to increase their storage stability. The Al/CuO composite film and Al/Cu/CuO composite film were aged for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C. Scanning electron microscopy and differential scanning calorimetry were used to analyze the microstructure and thermodynamic properties of the energetic films before and after aging, and the electrical detonation performance and ignition ability of energy-containing semiconductor bridges were studied. The results indicate that after aging for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C, the Al layer of the Al/CuO composite film becomes thinner, the Al2O3 interface layer increases, and the heat release decreases. The interlayer microstructure of the Al/Cu/CuO energetic multilayer nanofilms did not change significantly, and the addition of a 10 nm Cu layer formed a low-temperature Al–Cu alloy, reducing the reaction initiation temperature from 626 to 570 °C. The critical ignition time and critical ignition energy of the Al/CuO-energetic semiconductor bridge (ESCB) increased, the flame duration shortened from 440 to 300 μs, the flame size decreased by 50%, the plasma temperature decreased, and aging had no significant effect on the electrical explosion performance of Al/Cu/CuO-ESCB. After aging for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C, the maximum ignition gap of B/KNO3 for Al/CuO-ESCB decreased from 1.4 to 1.2 mm, while the maximum ignition gap for Al/Cu/CuO-ESCB remained at 1.6 mm, which significantly improved the ignition performance and long storage performance of the energetic semiconductor bridge. [ABSTRACT FROM AUTHOR]

As an important component of the chassis system, the vehicle suspension plays a significant role in vehicle comfort, stability, and safety. In dynamic modeling of a semi-active suspension, traditional method is a complicated process, the actuator force is difficult to solve. In the process of model simplification, the influence of the vehicle-axle and balanced shift quality on the vehicle dynamics is not considered. For this reason, applying the Udwadia–Kalaba approach to dynamic modeling and control for a three-axle semi-active truck suspension can establish a simple and accurate equivalent discrete system. By fixing the displacement and acceleration of the body, the simulation is conducted with real excitations between the road and six wheels, and the actuator control forces of the semi-active suspension are obtained under the constraint by applying the Udwadia–Kalaba approach. The contrast in the analysis results from the Udwadia–Kalaba approach and the traditional Lagrange multiplier method indicate that the Udwadia–Kalaba equation can obtain the semi-active suspension actuator forces without introducing additional Lagrange multipliers and that the actuator forces acquired with the Udwadia–Kalaba approach are equal to those of the traditional Lagrange multiplier method. [ABSTRACT FROM AUTHOR]

Quorum sensing system regulates the expression of genes related to bacterial growth, metabolism and other behaviors by sensing bacterial density, and controls the unified action of the entire bacterial population. This mechanism can ensure the normal secretion of bacterial metabolites and the stability of the biofilm microenvironment, providing protection for the formation of biofilms and the normal growth and reproduction of bacteria. Traditional Chinese medicine, capable of quorum sensing inhibition, can inhibit the formation of bacterial biofilms, reduce bacterial resistance, and enhance the anti-infection ability of antibiotics when combined with antibiotics. In recent years, the combination of traditional Chinese and Western medicine in the treatment of drug-resistant bacterial infections has become a research hotspot. Starting with the associations between quorum sensing, biofilm and drug-resistant bacteria, this paper reviews the relevant studies about the combined application of traditional Chinese medicines as quorum sensing inhibitors with antibiotics in the treatment of drug-resistant bacteria. This review is expected to provide ideas for the development of new clinical treatment methods and novel anti-infection drugs.

Physical attributes of Chinese herbal extracts are determined by their chemical components, and the physical and chemical attributes jointly affect the preparation process performance and the final product quality. Therefore, in order to improve the quality control of Chinese herbal extracts, we should comprehensively study the batch-to-batch consistency of physical and chemical attributes as well as the correlations between them. This paper first explored the physical attributes affecting the preparation process performance of the compound Danshen extract and developed a method for characterizing the texture attributes. With such main chemical components as water, phenolic acids, saponins, and saccharides and texture, rheology, and other physical attributes taken into consideration, the batch-to-batch quality fluctuation of products from different production lines and time was analyzed by principal components analysis(PCA). Finally, the correlation and partial least squares(PLS) analysis was conducted, and the regression equation was established. The fitting result of the PLS model for dynamic viscosity was satisfying(R~2Y=0.857, Q~2=0.793), suggesting that the chemical components could be adjusted by the component transfer rate in the extraction process, the impurity removal rate in the alcohol precipitation process, and the water retention rate of the concentration process to meet the control of the extract dynamic viscosity. This study clarified the correlations between physical and chemical attributes of the compound Danshen extract and established a method for controlling its physical attributes based on process regulation, which would provide reference for improving the quality control of Chinese herbal extracts.