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As a magical material with powerful functions, graphene has recent high strength, excellent thermal conductivity, and good biological compatibility. In recent years, it has attracted the attention of the scientific and public worlds. Considering the prospects of extensive research in graphene, this paper uses the results of the predecessor used in the panoramic method to summarize the research and application of graphene. Specifically, this paper introduces the basic information of graphene including the simple concepts, structures, and main preparation methods. The advantages and weaknesses of different preparation methods (Mechanical Exfoliation Method, Redox method, Exogenous extension method (SiC), Liquid Phase Epitaxy, Vapor deposition method, and Solvothermal method) are compared. In terms of applications, this paper summarizes graphene applied in the current anode materials of the battery, and the field of medical application (dental planting, bone tissue engineering project). The current production rate of graphene is low, the quality of graphene is not high, and the quality of graphene is low. On this basis, and the aspect of the performance of graphene improvement has been outlooked.

In order to study the mechanical properties of steel fiber rubber recycled brick concrete, ten groups of recycled brick concrete specimens with the strength of 15MPa were tested , one group was purely recycled brick concrete, the remaining nine groups mixed with different rations of admixture. Three groups mixed with steel fiber, another three groups mixed with rubber granules, the last three groups mixed with both steel fiber and rubber granules. These concrete specimens were tested by pressure testing machine respectively, the maximum strength is calculated by its maximum stress value. The results proved that: when adding steel fiber to recycled brick concrete can improve the strength of concrete, the higher the percentage of steel fiber was added, the more obvious the increases in strength. The recycled brick concrete mixed with rubber granules showed a reduced strength of the concrete, the higher percentage of rubber granules were added, the more significant drop in strength. When added the same percentage of both steel fiber and rubber granules, the result showed an increased strength of recycled brick concrete, as the percentage of two kinds of admixture dosage increases simultaneously, the strength increases rapidly.

The problem of road traffic safety has been widely concerned in recent years. The identification of traffic accident hot spots can effectively improve the road traffic safety and let the traffic managers formulate targeted improvement measures and suggestions. The traditional identification method of accident hot spot does not consider the spatial attribute of the accident, so it has some limitations in the identification of traffic accident hot area. Therefore, this paper first proposes a method to identify the hot spot of traffic accidents based on geographic information system (GIS). The mathematical model and machine learning model are used to explore the correlation between traffic accidents and spatial characteristics from macro and micro aspects. Finally, taking Beijing as an example, the feasibility of the research method is proved by using the accident data of Beijing in 2015 and the geographic information of Beijing. The research results of this paper can realize the spatial effective transformation of accident records, comprehensively consider the micro and macro attributes of the accident itself, realize the automatic and efficient identification of the accident hot spot. In addition, the causality analysis results between each attribute and the distribution of accident hot spots can help decision makers to formulate safety and sustainable road strategies.