The NiCo₂O₄ nanorods were prepared by a hydrothermal method with nickel nitrate hexahydrate （Ni(NO₃)₂·6H₂O） as the nickel source,cobalt nitrate hexahydrate （Co(NO₃)₂·6H₂O） as the cobalt source,and urea as the precipitant.Then the above NiCo₂O₄ nanorods were immersed into the RuCl₃ solution to obtain the NiCo₂O₄/Ru composite catalyst by reduction.Testing technologies such as X?ray diffraction (XRD) and scanning electron microscopy (SEM) were adopted to characterize the phase structure and morphology of this composite catalyst, and its catalytic performance toward the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) was investigated by electrochemical methods such as linear scan voltammogram (LSV) and electrochemical impedance spectroscopy (EIS). Moreover, the NiCo₂O₄/Ru composite catalyst was used as the anode to assemble the Zn?air battery, whose open circuit voltage,charge and discharge performance,and cycle stability were evaluated by a LANHE test system. The results show that the NiCo₂O₄/Ru composite catalyst has high ORR/OER bifunctional catalytic activity with an OER overpotential of 420 mV at 10.0 mA/cm² and an ORR half?wave potential of 0.77 V.The assembled Zn?air battery also exhibits an open circuit voltage of 1.37 V, a maximum power density of 143 mW/cm²,as well as robust cycle stability for 50 hours.

According to the characteristics of coal reservoir in Qinduan block, the experimental research on proppant optimization and fracture conductivity were conducted. The experiment contrastively analyzed the factors such as sand mass concentration, proppant particle size, proppant particle size combination, proppant embedment, and their effects on conductivity of fracturing under the condition of various closure pressures. Fracturing proppant system was optimized through experimental study. The results show that the conductivity of proppant pack decreased along with the increasing of closure pressures, so if the fracturing conditions was permitted, we should use large diameter proppant as much as possible; Qinduan block should adopt the 20/40 mesh and 16/20 mesh Lanzhou silica sand as fracturing proppant, and when the ratio was 4∶1, the combination is appropriate; increasing sand mass concentration can increase fracture conductivity to some extent and reduce the impact of proppant embedment on the conductivity.

Considering the micro level simulation that microfluidic device could provide and the character of porous medium in reservoir, this experiment made the use of microfluidic device to simulate spontaneous imbibition process, which is the main oil displacing mechanism in fractured reservoir to get the relationship between the distance of displacing front and time, the velocity of displacing front and time, finally, it makes us to have a further understanding of spontaneous imbibition.