Workers build the second production line of melt-blown nonwoven fabric, a key material for masks, at a factory of Sinopec, in Yizheng, east China's Jiangsu Province, March 27, 2020. The first production line started operation on March 29, producing over one ton of melt-blown nonwoven fabric daily, which can be further processed into one million medical masks. (Xinhua/Ji Chunpeng)
