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The electric vehicle, if accessed in the distribution network disorderly and extensively, will influence the safe, stable, and economic operation of the network, due to the characteristics of its randomness, intermittency, and duality with source and load. Here, the power demand models of different electric vehicles were established by analysing the behaviour of electric vehicle loads attributed to different users, and the spatial-temporal distribution pattern of various electric vehicle loads in the distribution network was predicted with the Monte–Carlo method. Based on this regular pattern, an evaluation method for the adaptability of the distribution network to electric vehicles was proposed. Finally, the influence of electric vehicle loads under different access modes on the static voltage stability margin was tested with the IEEE33 node distribution network.

In this study, the effect of joint on the anisotropy of a homogeneous, stiff, and intact sandy slate from a typical hydropower station is investigated by selecting and making jointed rock samples with jointed angles of 0°, 30°, 45°, 60°, and 90°. Accordingly, an acoustic measurement and a triaxial compression test are conducted on these jointed rock samples. The research results show that the joint angle significantly influences the rock mass anisotropy. In other words, the average value of the longitudinal wave velocity of the jointed rock samples is smaller than that of the intact rock. Furthermore, the value of the longitudinal wave velocity increases with the increase of the joint angle and is the largest when its spreading direction is in line with the joint inclination. The stress–strain curve, elastic modulus, peak strength, and failure mode of the joint rock samples are found to have anisotropic features. The failure stage occurs in samples with joint angles of 0°, 30°, and 90°. The stress–strain curve of the samples with joint angles of 45° and 60° tends to be horizontal. Meanwhile, the elastic modulus and the compression strength displayed a U-shaped distribution with an increase of the joint angle and the smallest value that belongs to samples with joint angles of 30° and 60°. The peak value ratio of the elastic modulus and the compression strength gradually decrease when the confining pressure increases, indicating that the anisotropy of the samples has weakened (i.e., the increase of the confining pressure decreases the anisotropy of the sandy slate strength). The failure mode of the samples with different joint angles is presented as follows: the samples with a 0° joint angle exhibit a tensile splitting damage; the samples with a 90° joint angle exhibit compression–shear damage; the samples with a 30°joint angle exhibit the combination of slide and compression–shear damage; and the samples with 45° and 60°joint angles exhibit slide damage along the joint surface.

Oleuropein was extracted from olive leaves by ultrasonic-assisted method and purified by silica gel column chromatography. The sample was identified as oleuropein by UV, infrared, mass spectroscopy and nuclear magnetic resonance spectroscopy analysis. Oleuropein and total phenolic contents over a year were determined by high-performance liquid chromatography and Folin–Ciocalteu methods. The results showed that 13.52% of pure oleuropein was found with a high purity of 96.54% and purification efficiency of 78.49%. Oleuropein and total phenolic contents of different olive varieties were quite different, but both had similar trends over the year. Five methods, including DPPH (2,2-diphenyl-1-picrylhydrazyl), ABST (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt), ferric reducing antioxidant power, total reducing power and nitrite-scavenging ability, were used to evaluate the antioxidant activities of oleuropein, and the IC50 were 34.54 ± 0.14 μg/mL, 18.79 ± 0.82 μg/mL, 75.32 ± 1.83 μg/mL, 13.80 ± 0.68 μg/mL and 1.00 ± 0.08 mg/mL, respectively. Practical Applications This study provides information on the changes in contents including oleuropein and total phenolics in a year to help understand the relationship between content of oleuropein and various influencing factors. Currently, the metabolic pathways of oleuropein are not clear. These results provide information for the study of the metabolism of phenolic compounds in olive and promote research at the molecular level. Oleuropein occupies a large proportion of total polyphenols in olive and can be to be purified by silica gel column chromatography with high purification efficiency for industrial production and laboratory production. In addition, the comprehensive evaluation of activity in vitro shows that oleuropein is more useful than BHT (2,6-di-tert-butyl-4-methylphenol) for the application in food and human health.

The power fluctuation of distributed generation has a negative effect on the power quality, losses and operation safety, and a good solution is to mitigate the power fluctuation near the grid-connected point of this generation. A new method for mitigating grid-side power fluctuation by the grid-connected inverter itself is proposed in this paper. A certain capacity of Li-ion supercapacitor is used as the dc-link capacitor of the grid-connected inverter first, and then a dc voltage follow-up control of the grid-connected inverter is adapted to charge/discharge the Li-ion capacitor indirectly. Finally, the power fluctuation of the renewable energy generation is well compensated by the charge/discharge power of the Li-ion capacitor, and the grid-side power has been smoothed. Taking a PV generation system as an example, the simulation results show that the dc voltage follow-up control of the grid-connected inverter can effectively mitigate its grid-side power fluctuation.