Four big international companies, including the oil giant Exxon Mobil, said yesterday that they would give Stanford University $225 million over 10 years for research on ways to meet growing energy needs without worsening global warming. Exxon Mobil, whose pledge of $100 million makes it the biggest of the four contributors, issued a statement saying new techniques for producing energy while reducing emissions of heat-trapping greenhouse gases were "vital to meeting energy needs in the industrialized and developing world." Many scientists and environment experts said the Stanford project was likely to be a valuable new assault on a serious environmental...