Conventional hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) were performed to obtain the volatile oils of Agrimonia pilosa Ledeb. harvested in three different regions of China, which were subsequently characterized by GC-FID and GC/MS analyses. Compared with HD, MAHD was advantageous in terms of energy savings and extraction time (60 vs. 240 min for MAHD and HD, resp.). The chemical composition varied among the different oils obtained, and the variations in the contents of the main constituents of the oils were irregular. Hence, these variations affected both the quantity and composition of the oils. The oil yields (0.15-0.21%) were affected by the method of extraction and the region of harvest, with the maximum amount of oil obtained by MAHD for the plants collected in Hubei (HB) and the minimum yield obtained by HD for the plants from Zhejing (ZJ). Hexadecanoic acid constituted the major compound of the essential oils, with the highest content found in the oil obtained by HD for plants from HB (41.18%) and the lowest one found in the oil obtained by MAHD from plants from ZJ (11.83%). Microwave irradiation did not adversely affect the composition of the essential oils. The findings show that MAHD is a modern, green, and fast technology.

Summary This study is focused on the isolation and characterisation of two purified polysaccharide fractions (namely PPEP‐1 and PPEP‐2) from Pleurotus eryngii (P. eryngii) and evaluation of their hypolipidaemic effects. The Congo red analysis indicated that PPEP‐2 but not PPEP‐1 possessed a triple‐helix conformation. The atomic force microscope analysis revealed that PPEP‐1 and PPEP‐2 showed different polysaccharide chain conformations. Importantly, the mice treated with PPEP‐1 showed significantly lowered serum levels of total cholesterol (TC), triglyceride (TG) and low‐density lipoprotein cholesterol (LDL‐c) and increased high‐density lipoprotein cholesterol when compared with the hyperlipidaemia mice induced by the high‐fat diet. However, PPEP‐2 revealed less hypolipidaemic effect than PPEP‐1. Additionally, both PPEP‐1 and PPEP‐2 demonstrated remarkable hypolipidaemic effects by decreasing levels of serum TC, TG and LDL‐c in the hyperlipidaemic model induced by P‐407. Taken together, our findings suggest that the P. eryngii polysaccharides, especially PPEP‐1, could be developed as a natural functional food supplement for preventing hyperlipidaemia.

As the core device of the deep-sea mining transport system, the slurry pump and its internal solid-liquid two-phase flow are extremely complicated; especially, the migration characteristics of particles have a great influence on the flow and wear of the pump. In order to grasp the particle motion law inside the slurry pump, this paper took into consideration the collision effects of the particles with particles and particles with walls and calculated the unsteady flow of the solid-liquid two-phase by CFD-DEM coupling algorithm. Then, the focus was put on the spatial distribution and movement characteristics of different particle diameters (namely, 5 mm, 10 mm, and 15 mm, while volume concentration Cv is constant 5%). The results show that the stratification phenomenon gradually disappears with the increase of particle diameter, and the intensity and scale of the vortex in the guide vane also increase obviously. Besides, as the particle diameter increases, the velocity changes more drastically, and the intensity and scale of the vortex increase significantly. Under low concentration conditions, the presence of particles has a limited influence on the hydraulic performance of the pump. By comparing with the experimental results, the simulation results are in good agreement with it, which proves that the CFD-DEM simulation in this paper is effective, and the conclusions can provide theoretical support for the design and analysis of the slurry pump in engineering application.

The simulation study is proposed to analyze the wear property of the axial flow pump using the sewage as medium. Different axial flow pumps are designed with different back-swept angles, of which are 40°, 65°, and 90°. Numerical simulation results showed the relationship between solid volume fraction and back-swept angle on the pressure/suction surface, as well as the particle diameter. To validate the correctness of numerical investigation, the result of the 65° backswept blade model was compared with a sludge axial flow pump in sewage treatment plant, which showed fair agreement with the simulated results.