A kind of novel uniform monodispersed three-dimensional dendritic mesoporous silica nanospheres (3D-dendritic MSNSs) has been successfully synthesized for the first time. The 3D-dendritic MSNSs can have hierarchical mesostructure with multigenerational, tunable center-radial, and dendritic mesopore channels. The synthesis was carried out in the heterogeneous oil-water biphase stratification reaction system, which allowed the self-assembly of reactants taking place in the oil-water interface for one-pot continuous interfacial growth. The average pore size of each generation for the 3D-dendritic MSNSs can be adjusted from 2.8 to 13 nm independently, which can be controlled by the varied hydrophobic solvents and concentration of silica source in the upper oil phase. The thickness of each generation can be tuned from ∼ 5 to 180 nm as desired, which can be controlled by the reaction time and amount of silica source. The biphase stratification approach can also be used to prepare other core-shell and functional mesoporous materials such as Au nanoparticle@3D-dendritic MSNS and Ag nanocube@3D-dendritic MSNS composites. The 3D-dendritic MSNSs show their unique advantage for protein loading and releasing due to their tunable large pore sizes and smart hierarchical mesostructures. The maximum loading capacity of bovine β-lactoglobulin with 3D-dendritic MSNSs can reach as high as 62.1 wt % due to their large pore volume, and the simulated protein releasing process can be tuned from 24 to 96 h by flexible mesostructures. More importantly, the releasing rates are partly dependent on the hierarchical biodegradation, because the 3D-dendritic MSNSs with larger pore sizes have faster simulated biodegradation rates in simulated body fluid. The most rapid simulated biodegradation can be finished entirely in 24 h, which has been greatly shortened than two weeks for the mesoporous silica reported previously. As the inorganic mesoporous materials, 3D-dendritic MSNSs show excellent biocompatibility, and it would have a hopeful prospect in the clinical applications.

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Carbon dioxide injectivity has always been considered as one of the optimum enhanced recovery techniques, especially in tight reservoirs regarding the feasible mobilization of gas through porous media. To have a better understanding of carbon dioxide injectivity performances, it would be of importance to consider crucial parameters and their effects on the carbon dioxide adsorption and oil recovery factor. In this paper, the profound impact of crucial parameters such as temperature, pressure, carbon dioxide soaking time, and core stimulation on the oil recovery enhancement were investigated. Moreover, the considerable influence of pressure and temperature on the carbon dioxide adsorption capacity storage were performed and analyzed. According to the result of this experiment, temperature increase led to reducing carbon dioxide storage capacity, which has a reverse pattern with oil recovery factor by increasing temperature. When the core samples were unstimulated, the oil recovery factor has higher than stimulated core samples. Furthermore, pressure increase resulted in the carbon dioxide storage capacity enhancement, which has a similar increase pattern with oil recovery factor by increasing pressure. The maximum carbon dioxide storage capacity is 91% and 90% at the pressure of 1500 psi and temperature of 20 ℃ respectively.Soaking time rising between oil and carbon dioxide led to producing more oil volume.

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