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Aiming at the problems that the surface deformation is complex under the condition of repeated mining of adjacent working faces and the conventional D-InSAR method is easily affected by factors such as time decorrelation and atmospheric delay, this paper takes Dongtan Coal Mine as the research object, and adopts the SBAS-InSAR method to process the 40-scene Sentinel-1A data, the annual average subsidence rate and time series accumulated subsidence of the study area were obtained, and the deformation characteristics were analyzed. The results show that the mining effect of 6303 adjacent working face on the existing working face is significant. Under the mining conditions of adjacent working face, the surface subsidence rate is fast, the scope is wide, and the subsidence basin shape is irregular. The subsidence amount of 6303 working face in the strike and inclination is obviously different, showing the characteristics of asymmetry. InSAR technology can effectively monitor the surface subsidence phenomenon of adjacent mining face, which can provide a reference for the analysis of surface deformation in mining area under similar complex mining conditions.

To improve the dust reduction efficiency of coal seam water injection, two kinds of non-ionic and two kinds of anionic surfactants were selected to study the surface tension and wetting characteristics of monomer and composite surfactant solutions. The synergistic wetting effect of composite surfactant solution on hydrophobic coal is compared and analyzed, the mechanism of synergistic wetting is discussed, and the field test of coal seam water injection is carried out. The wettability experiment of monomer surfactant shows that the wettability of the four surfactants is still gradually enhanced after exceeding the critical micelle (CMC) concentration. The experimental results of synergistic wettability of composite surfactant show that there is a significant synergistic effect between non-ionic surfactant TX-100 and anionic surfactant DSS, and that the synergistic effect gradually increases with the increase of surfactant mass concentration. When the total mass concentration was 1%, the synergistic rate was 60.06% and 132.03%, respectively, compared with TX-100 and DSS monomer solution. The mechanism of synergistic wetting was analyzed based on the principle of interfacial chemistry. It was found that the key reason for the synergistic wetting effect of hydrophobic coal dust was the significant increase of the dissociation rate of surfactant micelles in high concentration composite surfactant solution. The coal seam water injection test was carried out on the fully mechanized excavation face. After adding 1% TX-100: DSS composite surfactant solution for water injection, the dust reduction rate reached 71.04%, which was 43.45% higher than that of adding 0.05% TX-100 solution, indicating that the high concentration composite surfactant has a significant synergistic wetting effect on hydrophobic coal.

Synthetic micro/nanomotors have attracted considerable attention due to their promising potential in the field of biomedicine. Despite their great potential, major micromotors require chemical fuels or complex devices to generate external physical fields for propulsion. Therefore, for future practical medical and environmental applications, Mg-based micromotors that exhibit water-powered movement and thus eliminate the need for toxic fuels, and that display optimal biocompatibility and biodegradability, are attracting attention. In this review, we summarized the recent microarchitectural design of Mg-based micromotors for biomedical applications. We also highlight the mechanism for realizing their water-powered motility. Furthermore, recent biomedical and environmental applications of Mg-based micromotors are introduced. We envision that advanced Mg-based micromotors will have a profound impact in biomedicine. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Guanosine‐based hydrogels have attracted considerable attention because of their simplicity and easy preparation. However, the sugar moiety limits its further applications because of the necessity of sugar in the hydrogel formation. This work reports a G‐quadruplexes‐based hydrogel consisting of guanine and peptide epitope to form a supramolecular hydrogel in the presence of metal cations. Using the metal ion‐responsive peptide epitope from the ion channel to replace sugar motif at N9 position of guanosine results in a novel nucleopeptide. The results show that the gelation time, the diameter of nanofibers, the anisotropic property, and the mechanical property of the hydrogel can be simply controlled using metal cations. The magnesium and calcium ions direct the alignment of nanofibers to form anisotropic nano‐bundles. The mechanistic studies indicate the formation of G‐quadruplexes in the hydrogel. Compared to the storage modulus of nucleopeptide without the metal cation, adding zinc ions results in an over three‐order increase in mechanical properties. Cytotoxicity experiment indicates the good biocompatibility of our hydrogel. Moreover, we demonstrate that the guanine‐capped peptide could release STING agonist in a controlled manner. This work illustrates a simple way to modulate the property of the nucleopeptide hydrogel to develop soft materials. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Guanosine‐based hydrogels have attracted considerable attention because of their simplicity and easy preparation. However, the sugar moiety limits its further applications because of the necessity of sugar in the hydrogel formation. This work reports a G‐quadruplexes‐based hydrogel consisting of guanine and peptide epitope to form a supramolecular hydrogel in the presence of metal cations. Using the metal ion‐responsive peptide epitope from the ion channel to replace sugar motif at N9 position of guanosine results in a novel nucleopeptide. The results show that the gelation time, the diameter of nanofibers, the anisotropic property, and the mechanical property of the hydrogel can be simply controlled using metal cations. The magnesium and calcium ions direct the alignment of nanofibers to form anisotropic nano‐bundles. The mechanistic studies indicate the formation of G‐quadruplexes in the hydrogel. Compared to the storage modulus of nucleopeptide without the metal cation, adding zinc ions results in an over three‐order increase in mechanical properties. Cytotoxicity experiment indicates the good biocompatibility of our hydrogel. Moreover, we demonstrate that the guanine‐capped peptide could release STING agonist in a controlled manner. This work illustrates a simple way to modulate the property of the nucleopeptide hydrogel to develop soft materials. [ABSTRACT FROM AUTHOR]