• cement alternative
    April 13, 2015  

    Cement has been called the foundation of modern civilization, the stuff of highways, bridges, sidewalks and buildings of all sizes. But its production comes with a huge carbon footprint. Environmental chemist David Stone was seeking a way to keep iron from rusting when he stumbled upon a possible substitute that requires significantly less energy. Special correspondent Kathleen McCleery reports. Continue reading

  • May 27, 2010  

    Reports that more oil than originally thought is flowing into the Gulf of Mexico were tempered by early successes in the ‘top kill’ procedure to stop the leak at its source. Tom Bearden continues to track the progress of the spill with a team of researchers in Louisiana. Continue reading