The quasi-zero-stiffness vibration isolation system has witnessed significant development due to the pressing demands for low frequency and ultra-low frequency vibration isolation. In this study, the isolation theory and the characteristic of the quasi-zero-stiffness vibration isolation system are illustrated. Based on its implementation mechanics, a comprehensive assessment of recent advances of the quasi-zero-stiffness vibration isolation system is presented. The future research directions are finally prospected.

There are 6 samples of soybean paste which collected from market will be investigated. The results show that the total counts of lactic acid bacteria in the soybean paste samples was average 105-107cfu·g-1, but the total counts of molds and yeasts in some samples was just 103 cfu·g-1. And the total counts of bacillus in samples was over 105 cfu·g-1 .Compared with nature fermented soybean paste, the counts of molds and yeasts was down. The results indicate that the microbiological compositions of the soybean paste samples maybe changed. There were less total contents of flavonoids in the soybean paste, only up to 1.26 mg/g.

Gas valves are very important parts in compressors. If a valve fault in a compressor takes place, the expulsion of the compressor will decrease. In some critical cases, abnormal gas transmission will lead to a serious accident. This article proposes a method of fixed time basis in multi-resolution analysis and wavelet transform. This method can thoroughly resolve the problems occurred in present valve fault diagnosis caused by the fact that the wavelet transform does not have time shift invariance. By the analysis of experimental data, it shows that the valve fault can be preferably and accurately detected by using the method.

By measuring pH, acidity, mass concentration of free amino nitrogen and viable count of lactic acid bacteria from yogurt under refrigerated conditions, to study changes in the indicators of yogurt during the shelf. The results showed that during the yogurt shelf life, pH decreased, acidity increased, viable count of Lactobacillus was on the decline, nitrogen concentration of free amino acid increased less in the beginning of the refrigeration, but the indicators were still in line with national standards.