In view of the irregularity of the bottom floor of working face and the diversity of the shape of the flying gangue in steeply dipping coal seam, based on the geographic information system data such as contour line of bottom floor of working face, the 3d grid model of bottom floor is established, combined with the energy tracking method(ETM) C + + programs, four typical shapes of flying gangue with the same mass and different shapes are simulated to obtain the motion trajectories of the migration of flying gangue in the actual working face, as well as the velocity, angular velocity and energy change curves at any time. The influence of the shapes on the motion of flying gangue is analyzed. In order to verify the accuracy and feasibility of the method in this paper, the trajectory simulated by Rockyfor3D software is compared. The results show that the transport capacity of ellipsoidal flying gangue is much higher than that of polyhedral flying gangue. Compared with common polyhedral flying gangue, the regular polyhedral flying gangue has farther migration distance and less energy loss due to collision. The number of edges of flying gangue of regular polyhedron is inversely proportional to the energy loss of flying gangue in collision, which indicates that flying gangue of regular polyhedron with multiple edges is most likely to cause danger．

In order to improve the success rate of high temperature and complex formation structural oil wells, the preparative temperature sensitive self?consolidation resin is used to modify the surface of the aggregate material, and the thermally consolidated rigid plug material is obtained, then auxiliaries are chosen to build a novel bridge sealing and thermal consolidation plugging system that could resist temperature to 190 ℃. Infrared spectroscopy, thermal analysis, scanning electron microscopy were employed to study the molecular structure, microstructure and thermal stability of the resin, thermally consolidated rigid plug material and the plugging system, the suspension stability, consolidation rate, consolidation strength and permeability of the plugging system were also investigated. The results show that the constructed plugging system has the advantages of good suspension stability and wide solidification time window in bentonite slurry with mass fraction of 5%, and the compressive strength of the solidified body after curing at 90~190 ℃ are all over 6 MPa; at the same time, the water phase permeability of the solidified body cured at 190 ℃ is 6.32×10³ μm² under the driving pressure of 12 MPa, and the plugging rate is more than 98.00%. It is expected to meet the plugging requirements of high?temperature formation.

In this paper, the extraction process of flavonoids from Ligusticum was optimized by single factor test and response surface methodology, and the antioxidant experiment in vitro was carried out. The optimum extraction conditions were as follows: extraction time 2.5 h, extraction temperature 83 ℃, ethanol concentration 84%, liquid?solid ratio 35 L/g (the ratio of ethanol volume to Ligusticum jeholense powder sample mass). Under these conditions, the yield of flavonoids from Ligusticum was （22.64±0.18） mg/g. The results of antioxidant experiment in vitro showed that flavonoids from Ligusticum had certain antioxidant capacity. The clearing effect of ·DPPH is the best, the clearing effect of ·OH is the second, and the clearing effect of·O^2- is the worst. It also has the ability to restore Fe³⁺.