Why does China use iron instead of stainless steel for its railway tracks?China's railway construction, from the birth of the Shanghai Public Tramway in 1861 to the nationwide railway network today, has spanned over a century, witnessing technological advancements and the changing times. Throughout this long development process, the materials used for railway tracks have evolved from cast iron to steel and then to high manganese steel...

In the era of the Internet, mobile payment has become an indispensable part of people's daily lives. WeChat payment and Alipay payment are undoubtedly the two mainstream payment methods...