Enhancing the Strength and Ductility Synergy of Lightweight Ti-Rich Medium-Entropy Alloys through Ni Microalloying.

Medium-entropy alloys (MEAs) have attracted considerable attention in recent decades due to their exceptional material properties and design flexibility. In this study, lightweight and non-equiatomic MEAs with low density (~5 g/cm), high strength (yield strength: 1200 MPa), and high ductility (plastic deformation: ≧10%) were explored. We fine-tuned a previously developed Ti-rich MEA by microalloying it with small amounts of Ni (reducing the atomic radius and increasing the elastic modulus) through solid solution strengthening to achieve a series of MEAs with enhanced mechanical properties.

[Comparative Analysis on the Improvement of Air Quality in Beijing During APEC].

In order to evaluate the effects of the implementation of emission reduction measures and the revolution of air quality of Beijing during APEC, the evolution characteristics of air quality was analyzed based on the hourly monitored readings of Olympic Sports Center from 1 to 15 November 2014 released by Environmental Monitoring Station of China, and compared with that in 2013. The results showed that: (1) PM₂.₅ was the main pollutant in Beijing.

[Comparative Analysis and Inspiration of Air Quality Index Between China and America].

Research on the differences of air quality index (AQI) especially AQI of particulate matters between China and America and analysis of hourly monitored readings from April to December in 2013 released by Environmental Monitoring Station of China indicated that: (1) Although China lagged behind America in formulating and publishing of AQI standards, the AQI standards published in 2012 in China covered more pollutant indexes than before and could objectively reflect the characteristics of air pollution in China, and were more close to the residens's feeling about air quality. (2) The methods adopted for calculation of particulate matter hourly AQI were different in China and America, and the comparison revealed that the calculation method adopted by China using the 24 h average concentration breakpoint of particulate matters to replace the 1 h average concentration breakpoint would enhance the severity of the pollution level. (3) The breakpoint of PM2.