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Higher alcohols are not only the key flavor substance but also the precursor of other flavor substances in Baijiu. In the metabolic pathway of higher alcohols, alcohol dehydrogenase (ADH) plays an important role and its genes can be used as a marker gene for analyzing the producer of higher alcohols. In this study, the degenerate primers of Zinc-dependent long-chain ADH gene (L.adh) were designed and applied to investigate the diversity of L.adh in different Daqu (HT, SC and SD). The results showed that the degenerate primers were able to amplify the fragment of L.adh and had good coverage in high-throughput sequencing. The diversity and composition of L.adh in the three kinds of Daqu were different and the diversity of L.adh in SC was the highest while HT was the lowest. The predominant L.adh in SC and HT were form Bacillus (54%–78%) and Aspergillus (64%–66%), respectively, and the predominant L.adh in SD were from Aspergillus (7%–51%) and Enterobacter (2%–47%). In addition, L.adh from bacteria and fungi could be clustered into one evolutionary branch and divided into 10 clusters. The findings of this study will provide a new perspective for evaluating the potential microorganisms associated with higher alcohol synthesis in Daqu and reference for selecting suitable Daqu in the production of Baijiu.

Abstract To study the damage mechanism of multi‐anchor piles in tunnel crossing landslide area under earthquake, the damping performance of multi‐anchor piles was discussed. The energy dissipation springs were used as the optimization device of the anchor head to carry out the shaking table comparison test on the reinforced slope. The Hilbert spectrum and Hilbert marginal spectrum were proposed to analyze the seismic damage mechanism of the multi‐anchor piles, and the peak Fourier spectrum amplitude (PFSA) was used to verify the effectiveness of the method. The results show that the seismic energy is concentrated in the high‐frequency component (30–40 Hz) of the Hilbert spectrum and the low‐frequency component (12–30 Hz) of the marginal spectrum. This indicates that they can be combined with the distribution law of the PFSA to identify the overall and local dynamic responses of the multi‐anchored piles, respectively. The stretchable deformation of the energy‐dissipation springs improves the coordination of the multi‐anchor piles, resulting in better pile integrity. The damage mechanism of the multi‐anchor piles is elucidated based on the energy method: local damage at the top and middle areas of the multi‐anchor piles is mainly caused by the low‐frequency component (12–30 Hz) of the marginal spectrum under the action of 0.15g and 0.20g seismic intensities. As the seismic intensity increases to 0.30g, the dynamic response of the slope is further amplified by the high‐frequency component (30–40 Hz) of the Hilbert energy spectrum, which leads to the overall damage of the multi‐anchor piles.

Abstract Water lubricated guide bearings for hydro turbines and pumps are conventionally designed with multiple axial grooves to provide effectively cooling and flushing away abrasives. Due to the variety of groove configuration in terms of number and size, a predication of their performance is difficult. This paper deals with an analytical procedure to investigate groove effect on load capacity, stiffness and damping for this type of bearing where it is considered as an assembly of many inclined slide bearings. The result can be applied to bearings made of hard materials combined with low bearing pressure.