Flower-like ZnO microstructures were successfully synthesized via a facile hydrothermal route without using any surfactants. The morphology of these microstructures can be easily controlled by adjusting the pH of the reaction solution. The possible growth mechanism of ZnO hierarchical microstructures was proposed based on the X-ray powder diffraction (XRD) and scanning electron microscope (SEM) results. The photocatalytic activity studies of ZnO nanocrystals demonstrated their excellent photocatalytic performance in degrading aqueous methylene blue (MB) under UV-A light irradiation. This higher photocatalytic activity of the ZnO nanoplates was mainly attributed to the exposed facets with the higher surface energy.

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The thesis theory combined with computer simulation, according to the thermal theory, the heat transfer process of the surrounding rock in the coal mine roadway is simplified into an unstable state process, and the influencing factors of the unstable heat transfer coefficient of the surrounding rock are found, and the computer experimental system is used as the basis. At the same time, the paper constructs an experimental receipt according to the similarity theory, and uses the concrete specimen simulation like the thermal performance of the surrounding rock of coal mine as the coal mine roadway to realize the real-time simulation of the heat transfer process of the roadway. The unstable heat transfer coefficient of the surrounding rock under different wind speeds and ventilation specimens was tested to find the law of variation. Finally, in the actual coal mining industry, different roadways are selected for borehole temperature measurement, and the temperature record body with temperature recording function is used for measurement. The calculation formula of the original rock layer temperature at different depths of the mine area is obtained, and the accuracy of the model is verified.