Aneurinibacillus uraniidurans sp. nov., a uranium-resistant bacterium isolated from uranium-contaminated soil.

A novel Gram-positive strain, B1T, was isolated from uranium-contaminated soil. The strain was aerobic, rod-shaped, spore-forming, and motile. The strain was able to grow at 20-45 °C, at pH 6.0-9.0, and in the presence of 0-3 % (w/v) NaCl. The complete genome size of the novel strain was 3 853 322 bp. The genomic DNA G+C content was 45.5 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain B1T has the highest similarity to Aneurinibacillus soli CB4T (96. 71 %). However, the novel strain showed an average nucleotide identity value of 89.02 % and a digital DNA-DNA hybridization value of 37.40 % with strain CB4T based on the genome sequences. The major fatty acids were iso-C15 : 0 and C16 : 0. The predominate respiratory quinone was MK7. Diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipids, an unidentified aminolipid and an unidentified lipid were identified as the major polar lipids. The phylogenetic, phenotypic, and chemotaxonomic analyses showed that strain B1T represents a novel species of the genus Aneurinibacillus, for which the name Aneurinibacillus uraniidurans sp. nov. is proposed. The type strain is B1T (=GDMCC 1.4080T=JCM 36228T). Experiments have shown that strain B1T demonstrates uranium tolerance.

Study on flow field characteristics of gas-liquid hydrocyclone separation under vibration conditions.

The complex vibration phenomenon occurs in the downhole environment of the gas-liquid hydrocyclone, which affects the flow field in the hydrocyclone. In order to study the influence of vibration on hydrocyclone separation, the characteristics of the flow field in the downhole gas-liquid hydrocyclone were analyzed and studied under the condition of vibration coupling. Based on Computational Fluid Dynamics (CFD), Computational Solid Mechanics Method (CSM) and fluid-solid coupling method, a fluid-solid coupling mechanical model of a gas-liquid cyclone is established. It is found that under the condition of vibration coupling, the velocity components in the three directions of the hydrocyclone flow field change obviously. The peak values of tangential velocity and axial velocity decrease, and the asymmetry of radial velocity increases. The distribution regularity of vorticity and turbulence intensity in the overflow pipe becomes worse. Among them, the vorticity intensity of the overflow pipe is obviously enhanced, and the higher turbulence intensity near the wall occupies more area distribution range. The gas-liquid separation efficiency of the hydrocyclone will decrease with the increase of the rotational speed of the screw pump, and the degree of reduction can reach more than 10%. However, this effect will decrease with the increase of the rotational speed of the screw pump, so the excitation effect caused by the rotational speed has a maximum limit on the flow field.