The U-shaped grooves, shown in this photo published on March 20, 2008, is a new agricultural irrigation facility that was jointly developed by Wufeng Cement Products Company in Jiaxing City in east China's Zhejiang Province and the local scientific research departments.
The grooves were made of slag, cement and fly ash and have formally passed the evaluation of the expert team from the Ministry of Water Resources.
(CRI March 21, 2008)