To ensure the effect of several rounds of profile control in Bohai oilfield, the adaptability of a drag-increasing in-situ gel profile control agent was investigated specifically in the study. The gelation property, thermal stability and micromorphology after gelation were measured by viscosimetry, rheological analysis and scanning electron microscope respectively. The injectivity, plugging property, selectivity and enhanced oil recovery effect of the profile control agent were investigated by sand packing experiments. The results show that the profile control agent has low initial viscosity, excellent injectability and deep migration performance, and weak chromatographic separation behavior in the reservoir. At the reservoir temperature of 65 ℃, it has a long gelation time, high gelation viscosity and good thermal stability. After gelation, it has a three-dimensional network structure with microspheres as cross-linked nodes inside, and demonstrates shear thickening characteristic at a shear rate of 4~12 s?1. Additionally, the profile control agent possesses excellent selective plugging performance and preferentially enters the breakthrough area to form plugging, , while maintaining a low oil plugging rate in the oil layers. The profile control agent shows a significant effect on enhancing oil recovery and the increase in crude oil recovery rate reaches 15.0%~23.0% after injecting 1.000 pore volume (PV). Generally, the drag-increasing in-situ gel profile control agent can adapt to the reservoir characteristics of Bohai offshore oilfield well, and realize in-depth profile control in the reservoir.

Based on density-functional theory (DFT) and wave function analysis procedures, the optical and molecular absorption properties of two structurally different pentacyclooxonium salt molecules have been investigated, and the physical mechanism of the formation of a built-in electric field due to orbital polarization caused by structural distortions, which induces charge transfer and leads to a nonlinear optical spectrum, has been explored.The properties result from the orbital polarization-induced built-in electric field driving charge transfer due to structural distortion. Theoretical analysis of ultraviolet-visible absorption spectroscopy (UV-vis) spectra is first performed to investigate the optical properties. The electronic excitation characteristics of the built-in electric field-driven charge transfer in molecules are analyzed in detail by transition density matrix (TDM) and charge differential density (CDD). Combining transition electric dipole moment density (TEDM) and transition magnetic dipole moment density (TMDM) analysis, the physical mechanism of the structure-induced chirality in their electronic circular dichroism (ECD) spectra is revealed. The results can provide theoretical references for the preparation of novel chiral materials as well as the research and development of optoelectronic materials and their practical applications.

Some strategies for improvement of the key technology of testing?adjusting integrated separate injection technology have been investigated, due to much lower efficiency of conventional testing?adjusting integrated separate injection technology, which cannot accomplish layered static pressure testing. Through optimizing the string structure to improve the pressure balance during water injection, the creep of the string caused by the large displacement water injection is reduced. Design of the bridge channel of the water distributor greatly increases the flow area,reduces the interlayer interference, and further improves the testing?adjusting efficiency. Meanwhile, the pressure hole is added in the water distributor body to establish stratum?tubing pressure transfer channel, and the static pressure testing instrument is equipped for further testing of the layered static pressure. The improved technology works well in application, the deployment efficiency has been significantly improved, which takes only 5 hours to complete the deployment of 6 layers. The overpressure layer can be successfully picked out during the layered static pressure test, which provides a basis for the layered injection allocation adjustment. The adaptability of the improved technology in Bohai oilfield is significantly enhanced.

The property and composition of ethylene cracking tar were investigated by four component analyses and the method of ndM. The results were shown that amount of the aromatic hydrocarbon, colloid and asphaltene was higher in the ethylene cracking tar. On the other hand, the delayed coke simulation test was carried on the selfmade apparatus based on the ethylene cracking tar as materials or doping different ratio of the ethylene cracking tar into the coking materials as material under the conditions was that the 500 ℃ and normal atmosphere. The results showed that the fraction of gasoline and wax oil was decreased, but the fraction of diesel oil and coke was increased under the doping ratio of ethylene cracking tar in coke material was increased. Compared with the industrial production device, under the doping ratio of ethylene cracking tar was 20%, the density of gasoline was nearly not changed, the fraction of sulfur and actual colloid were increased slightly, the initial boiling point and dry point of the middle distillate (200～350 ℃) was nearly not changed, however the density of the middle distillate (200～350 ℃) was increased, but the actual colloid was decreased. As for the coke, the fraction of volatile and ash was increased, but the fraction of water and sulfur was decreased apparent. The result mentioned above showed that the doping ratio of ethylene cracking tar was 20% will not affect apparently the production of the delayed coking. 