The adsorption sulfur capacity and selectivity are two key challenges for adsorption desulfurization technology of FCC gasoline. In order to improve the above issues, the mesopores were first introduced into ZSM-5 zeolites by a NaOH alkali treatment method to reduce the diffusion limitations and increase the sulfur capacity, in which the effects of the alkali concentration, treatment time, and temperature on the pore properties of zeolites were well discussed. The desulfurization performance was tested in a fixed-bed reactor using model fuel. The results demonstrated that the alkali treatment time was the most influential factor for the sulfur capacity. The mesoporous ZSM-5 adsorbents prepared under the conditions of 0.5 M NaOH, 150 min, and 75 °C showed the maximal sulfur capacity, the breakthrough and saturation sulfur capacities of which were 14.00 and 17.46 mg of S/g of adsorbent, respectively. In addition, Ni2+ ions were exchanged into mesoporous ZSM-5 zeolites to enhance the sulfur selectivity. The results proved that the selectivity of sulfur could be improved by an introduced metal ion because the Brönsted acid sites were decreased while the Lewis acid sites were increased.

Gas–liquid two-phase flow directly determines the efficiency and stability of the aeration tank. In this paper, a gas–liquid two-phase testbed is built to explore the aeration performance and internal flow in an aeration tank, including an inverted-umbrella impeller (immersion depth of 0 mm, rotational speed of 250 r/min). Also, the running process is simulated by computational fluid dynamics (CFD) with a population balance model (PBM), and mass transfer coefficient is compared to the experiment. The experimental results show that there is a big difference in bubble diameter, ranging from 0.4 to 1.6 mm. The simulation shows that the impeller intensely draws air above the free surface into the shallow liquid, and the circulation vortex entrains it to the bottom areas faster. Compared with the experiment, the simulated interfacial area and standard oxygen mass transfer coefficient is 12% more and 3% less, respectively. The results reveal that CFD-PBM coupled model can improve the accuracy of calculation, resulting in the simulation of gas–liquid two-phase flow.

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The base level during the deposition of Jurassic in the Qiangtang Basin shows a complete cycle from rising to falling. The base level change is closely connected with tectonic evolution of the basin, especially connected with Bangonghu-Nujiang ocean evolution process in the formation and evolution of the basin. It is also affected by climate. The Jurassic strata correspond to a long-term base level cycle sequence. The sequence is in fact a non-complete symmetrical cycle, consisting of rising hemicycle and falling hemicycle. It can be divided into 6 intermediate-term base level cycle sequences, including 2 carbonate sequences, 3 mixture sedimentary sequences of carbonate and clastic rocks and one clastic sedimentary sequence. Depositional filling characteristics during base level change show that Bangonghu-Nujiang ocean spreads in Toarcian-Bajocian ages, and is at the height of spreading of Bangonghu-Nujiang ocean in Bathonian-Oxfordian ages. In that process, sea area became smaller because of the dry climate. Eventually, marine depositional filling is ended with the subduction and collision of Bangonghu-Nujiang ocean.

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