手机在线观看黄色网址_成人午夜做爰视频免费看_精品一二三区久久aaa片_国产泡妞岁18xxxx免费看_色欲午夜无码久久久久久_国产原创视频在线

On Nov. 14th, 2013, Mr. Lv Qibing gave an academic report to Xihua University.

The title of the report is "the development of rail welding technology for  high-speed railway". Everybody had a lively exchange about the rail welding methods, welding quality control, rail welding standard construction and analysis of difficulties, etc..

This academic report has great inspiration and guidance for teachers and students in the School of Materials Science and Engineering.