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Dry UMCA(Ultrasonic Mechanical Coating and Armouring)is a deposition coating technology that only needs to be carried out under normal temperature and pressure, and its principle is similar to mechanical alloying.Although the UMCA process is still in the preliminary exploration stage in the world, it has shown great potential in coating preparation due to its unique advantages.The experiment method of UMCA was introduced and the influence laws of process parameters on coating quality was summarized.It was found that the influence laws of different material combinations had both similarities and differences.And the reasons for the difference were mainly analyzed from the perspective of energy.Besides, the possible formation mechanism of the coating was analyzed in a broad sense.Finally, the problems to be solved urgently and the development direction of UMCA process were put forward.

In the new era of China’s development for higher vocational college students have new quality development requirements, especially in terms of ideological quality, college students in the new era are required to have patriotic feelings and practical action, correct overall view of world development, and conscious view of global ecological environment protection. At a higher vocational college in Anhui province for two months investigation and study of the topic, through the data analysis found that some problems existing in the college students in the new era of ideological quality development: some college students of level of concern for domestic event and domestic security is not high, and the patriotic practical actions need to be further improved; Some of them have a shallow understanding of the international situation, and the ideological quality of a few college students does not meet the requirements of The times; College students have nearly for ecological environment protection is the lack of action. It puts forward the corresponding countermeasures and Suggestions: Guiding the college students pay attention to the national development, and to the right side of thinking, actively safeguard national interests; Guiding the youth to learn to distinguish right from wrong, and form a correct global vision and the soul of thought; Through the education of higher vocational college students to learn ecological security concept of national overall security, enhance their awareness of environmental protection, ecological security and the ability to consciously maintain ecological security.

In order to improve the availability of waste rubber tires and bearing capacity of sand foundation, a new composite foundation transforms the tensile strength of a discarded rubber tire into a hoop-tightening force on granular sand soil, i.e. hoop capacity, is introduced and investigated. Considering the characteristics of the circular enclosed structure of the tire, the tensile strength of the tire strips was obtained by carrying out a tension test of tire strips, and the relationships between earth pressure, settlement and vertical load were discovered by the results of loading tests under the conditions of confined and unconfined. The distribution of circumferential stress at each position of the tire cross section was monitored to evaluate the contribution of each part of the tire to the integral hoop capacity. Based on the theory of annular elasticity, Airy stress-state function is introduced to determine the solutions of stress, strain and displacement in the sand and tire regions based on the stress boundary condition and displacement continuity condition. The results show that the theory prediction curve has a high precision approaching the measured data, which indicates the rationality of the proposed theoretical model in predicting the circumferential stress of this type of waste rubber tire composite foundations. [ABSTRACT FROM AUTHOR]