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Unconventional machining processes, particularly ultrasonic vibration cutting (UVC), can overcome such technical bottlenecks. However, the precise mechanism through which UVC affects the in-service functional performance of advanced aerospace materials remains obscure. This limits their industrial application and requires a deeper understanding.

The surface integrity and in-service functional performance of advanced aerospace materials are important guarantees for safety and stability in the aerospace industry. For advanced aerospace materials, which are difficult-to-machine, conventional machining processes cannot meet the requirements of high in-service functional performance owing to rapid tool wear, low processing efficiency and high cutting forces and temperatures in the cutting area during machining.

To address this literature gap, this study is focused on the quantitative evaluation of the in-service functional performance (fatigue performance, wear resistance and corrosion resistance) of advanced aerospace materials. First, the characteristics and usage background of advanced aerospace materials are elaborated in detail. Second, the improved effect of UVC on in-service functional performance is summarized. We have also explored the unique advantages of UVC during the processing of advanced aerospace materials. Finally, in response to some of the limitations of UVC, future development directions are proposed, including improvements in ultrasound systems, upgrades in ultrasound processing objects and theoretical breakthroughs in in-service functional performance.

This study provides insights into the optimization of machining processes to improve the in-service functional performance of advanced aviation materials, particularly the use of UVC and its unique process advantages.

This paper aims to explore the use of joint distribution to reduce environmental cost of express delivery in urban logistics.

An optimization model was developed to help design the joint distribution network. A real case in Songjiang University Town of Shanghai, China, was used to explore empirically the potential benefit of the design. Performance of the proposed joint distribution was compared with that of the current distribution design using separate deliveries.

The findings show that, using joint distribution in express delivery, a significant saving in economic cost (up to a reduction of 25%) and environmental cost (up to a reduction of 87%) can be achieved.

This study provides a reference for joint distribution network design for last-mile delivery in urban logistics.

Express delivery companies can explore the use of joint distribution to reduce operating cost and increase distribution efficiency of the industry.

Joint distribution can facilitate maximization of vehicle utilization and reduction of delivery trips. This will help reduce fuel consumption, carbon emission, as well as other externalities, such as noise and traffic congestion.

Research in joint distribution to date focuses mainly on reduction in operating cost only. Consideration of environmental impact is relatively limited. This paper fills the gap in the literature by using a real case to illustrate the significant benefit of joint distribution in reducing the negative impact of urban logistics on the environment.

This paper describes the organic geochemical characteristics and their roles on barium enrichment in the No. 2 Coal from Huanglong Jurassic Coalfield, China. A total of 18 bench samples were taken from Huangling Mine 2. The average content of barium (3701 mg/kg) was about 23 times higher than that of common world coals. Terrestrial higher plants were the main coal-forming parent material. Relying on the parameters of OEP, Pr/Ph and so on, there is little correlation between organic geochemical characteristics and barium enrichment. Therefore, organic material has little influence on the process of coal-forming and the enrichment of barium.