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In order to find out the main sources of gas emission during drilling and clarify its change law, this paper takes Jiulishan Mine in Jiaozuo Mining Area as an example, and expounds the source, emission and variation law of gas emission during the drilling of floor rock roadway by measuring the amount of gas emission from coal pile and the gas concentration with different distances from the borehole to the windward side of the borehole. The results show that the amount of gas released from the coal stockpile is relatively low, and the gas volume fraction will not exceed the limit through normal ventilation. During normal drilling, the gas emission from the borehole is relatively high, and the gas concentration changes continuously at different distances from the borehole, and the overall trend is gradually decreasing. However, the gas concentration may still exceed the limit at the position 2 m away from the downwind side of the borehole.

In order to enhance the hydrophilicity and corrosion resistance of aluminum alloy surface， a hydrophilic surface was obtained on 2024 and 6061 aluminum alloy substrates by anodic oxidation，reaming and coating of sodium fluosilicate，and the surface morphology，elemental composition， wettability and electrochemical properties of the as-prepared hydrophilic surface were analyzed. Results showed that after anodizing with 15%(mass fraction) sulfuric acid solution， the oxide films of 2024 aluminum alloy and 6061 aluminum alloy presented the rough nano-particles and dispersed micropores respectively. And the oxide film of 2024 aluminum alloy could better combine with sodium fluorosilicate to form a surface film with good hydrophilic effect. These two kinds of aluminum alloys were coated in sodium fluorosilicate solution， and hydrophilic films with contact angles less than 30° were obtained. The average contact angle of 2024 aluminum alloy surface was 18.5° and both aluminum alloys obtained good hydrophilicity. The electrochemical test results showed that the corrosion resistance of 2024 and 6061 aluminum alloys both decreased after coating， and the corrosion resistance of 6061 aluminum alloy changed more obviously. In all， the hydrophilicity and corrosion resistance of 2024 aluminum alloy were better than those of 6061 aluminum alloy after coating.

Recently Fe3O4 nanoparticles have been widely used in drug delivery systems due to their excellent magnetic properties and good biocompatibility. However, the surface of Fe3O4 nanoparticles is prone to agglomeration if it is not modified, which will affect his application performance. In this paper, Fe3O4 is hydrolyzed by ethyl orthosilicate (TEOS) and coated with SiO2 layer. Then the carbon layer is coated by hydrothermal reaction. Finally, SiO2 is etched by NaOH to form a kind of Fe3O4@C coreshell nanomaterials. The structure and morphology of Fe3O4@C nanoparticles were characterized by FT-IR, TEM and UV-Vis absorption spectroscopy, and the interface modification and related properties of nanoparticles are studied. The results show that the magnetic properties of Fe3O4 are not affected by the modified Fe3O4@C, and the specific surface area and the loading rate of Fe3O4are improved. The loading rate of Fe3O4reaches 98.9%. The drug release behavior of the compound interface modified Fe3O4@C under different pH conditions is further studied to explore the possibility that pH value could be used as a 'switch' for controlled drug release. [ABSTRACT FROM AUTHOR]