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In recent years, new technologies involving self-suspending proppant (SSP), which improves proppant distribution, reduces the use of chemicals in fracturing fluids, and simplifies the fracturing construction process, have become a focus of hydraulic fracturing research. However, the available products have poor suspension stability, cannot withstand high temperature and salt environments, and are highly damaging to reservoirs. In this study, we presented a novel self-suspending (HTS-SSP) proppant with excellent suspension stability, temperature resistance, and salt resistance, prepared from quartz sand, silane coupling agent, and modified polyacrylamide to achieve these properties. Wettability tests, surface morphology analysis, and Fourier transform infrared spectroscopy analysis proved that 3-methacryloxypropyltrmethoxysilane (KH570) successfully modifies quartz sand, and the HTS-SSP was synthesized. In terms of the suspension performance, HTS-SSP exhibited exceptional suspension stability due to the incorporation of KH570. It remained suspended at 150 °C or 24 wt % brine and showed excellent temperature and salt resistance. The gel-breaking fluid of the surface polymer of HTS-SSP had low damage to the reservoir, much less than the guar gum fluid. The difference between the conductivity of the aggregate remaining after HTS-SSP gel-breaking and that of unmodified quartz sand was not significant. The synthesized HTS-SSP demonstrates outstanding comprehensive performance and is an ideal candidate for reservoir development under harsh temperature and salinity conditions.

In order to study the influence of drizzle weather on the total electric field of ultrahigh-voltage direct current (UHVDC) transmission lines, an ion flow field model considering drizzle weather is established. This model calculates not only the positive and negative ions but also the charged tiny water droplets, dust particles, and falling raindrops, enabling accurate simulation of the total electric field in drizzle weather. Meanwhile, the ion flow field model is solved by the improved upstream finite element method. First, the influence factors and mechanism of drizzle weather on the ion flow field of UHVDC transmission lines are studied in this article. Then, the improved upstream finite element method is used to solve the ion flow field under different degrees of drizzle weather. Finally, the influence rule of drizzle weather on the total electric field at ground level is obtained. In this article, the accuracy of the ion flow field model is proved by the measurement data of the ground-level ion flow field of the ±800-kV UHVDC transmission line from Chuxiong to Suidong. The research results show that the ion flow field of drizzle weather at ground level is larger than that of sunny weather. With the degree increase of drizzle weather, the peak value and distribution curve of the ground-level total electric field gradually increases. This article has a guiding role for the construction and the safe operation of UHVDC transmission lines considering drizzle weather.