Photo taken on July 23, 2017 shows a submersible device on China's independently-made marine science expedition vessel Kexue at a port in Xiamen, southeast China's Fujian Province. Kexue left Qingdao in east China's Shandong Province last Monday for a maritime scientific expedition and stopped in Xiamen, southeast China to resupply Friday after completing the first part of the mission. It left Xiamen on Sunday for the mission's second stage. (Xinhua/Zhang Xudong)