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In our previous work, the PD/γ-cyclodextrin complex was discovered to have higher calculated Kc and Gibbs free energy (ΔG0) values by the phase-solubility diagram method, and molecular dynamics (MD) simulations were carried out to investigate the structure and dynamics of the 1:1 inclusion complexes formed by β- and γ-cyclodextrins (CD) with PD in water. The simulation results indicated that γ-CD provides the most stable inclusion complex of among all PD-CD complexes in this study. Similar to the MD results, the thermodynamics of the selected inclusion complex structure was calculated by semi-empirical (PM3) and DFT (B3LYP/6-31G) methods. The statistical thermodynamics calculations also suggested that orientation b (including in CD's cavity from the wide side) of the PD/γ-CD inclusion complex is a favourable binding mode and in good agreement with the experimental and MD data. Most importantly, the simulation results of present study are in good agreement with the experimental data.

On the basis of high-resolution sequence stratigraphy, this paper establishes a sequence stratigraphic frame, and predicts reservoirs by analyzing velocity field, seismic inversion, and seismic attributes. In the case study of the Jurassic Toutunhe Formation braided river delta reservoir of Shinan 21 well block, middle of the Junggar Basin, space variant velocity field inversion and reservoir prediction were carried out based on the sequence stratigraphic frame and the reservoir prediction accuracy was improved. Comparing the prediction results with the real drilling shows that, when the burial depth of bed of interest is 2 500 m, the maximum prediction error of depth is only 10 m, and the average relative prediction error is 0.16%; for appraisal wells with an average effective sandstone of 13 m, the maximum prediction error of sandstone thickness is only 5 m. The structure mapping and reservoir prediction constrained by the sequence stratigraphic frame achieved success. Key words: sequence stratigraphic frame, reservoir prediction, Junggar Basin, braided river delta