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With the rapid development of China’s highway construction, the huge demand for funds and the lack of financial strength of the contradiction is increasingly obvious, can effectively control the maintenance costs, highway operators to obtain sustainable development advantages of the key factors. This paper measures the highway maintenance and management costs including carbon emission costs based on the perspective of life cycle cost analysis. Based on the perspective of life cycle cost analysis, prediction models are developed for each component cost of highway maintenance and management costs. The carbon emission costs generated during the operation duration of highways are also included in the life-cycle costs, and the calculation model is proposed for the strategy of “30∙60 carbon target” in China. In the example analysis, the carbon emission cost of new energy vehicles is only 3/4 of that of fuel vehicles in the driving phase; more than 90% of the carbon emission is generated by the driving vehicles.

Polyaza[3.3.3]propellanes have good symmetry and strong ring tension, which are suitable as the skeleton structure of functional materials such as high energy density materials. Based on the single benzyl derivative of 3,7,9.11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane (compound 3 ), a series of 2,4,6,8,10- pentaaza[3.3.3]propellane derivatives, such as 4a-c and their reduced derivatives 5a-c, were synthesized successfully.

An experimental study was carried out to investigate the effect of acid etching on surface integrity of a single crystal nickelbased superalloy. The corrosion tests were conducted in solution of hydrochloric acid and hydrogen peroxide at different reaction temperatures. The corroded specimens were characterized by scanning electron microscopy, weight loss measurements and surface roughness measuring instrument. The results indicate that DD6 suffers serious selective corrosion at cold bath temperature due to unduly slow etching when immersed for the maximum time. It is found that preferential dissolution of γ′ phase occurred, leading to the increase of surface roughness.