ASH 1 (IMAGE) Rice University Caption A scanning electron microscope image shows raw, type C fly ash particles made primarily of calcium oxide as a byproduct of coal-fired power plants. Rice University engineers have made a cementless, environmentally friendly binder for concrete that shows potential to replace Portland cement in many applications. Credit Multiscale Materials Laboratory/Rice University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.