发现可以给手机充电的细菌（在线收听）

     　　Bacteria Discovered To Recharge Cell Phone

           A microbe called Rhodoferax Ferrireducens，found in the mud at Oyster Bay，Virginia，has been discovered to transfer electrons directly onto an electrode as it metabolizes sugar into electricity．"You can harvest enough electricity to power a cell phone battery for about four days from a sugar cube，"researcher Derek Lovley says．"A cup of sugar contains enough power to light a 60－watt light bulb for about 17 hours．"This process is accomplished at an astonishing 80% efficiency and produces only carbon dioxide gas as a byproduct．Previous similar reactions progressed at only 1% efficiency and required toxic metallic mediator chemicals to assist，avoided here because the bacteria grows happily as a slime colony directly on the electrode plates．The bioreaction was found to work not only with glucosebut also with the fruit sugar fructose，with sucrose（found in sugar cane and sugar beet）and even xylose，a sugary byproduct of wood and straw．In addition，the bacterium is rugged and stable，able to grow at temperatures ranging from four to 30℃，with 25℃the optimum．If engineering obstacles can beovercome and manufacturing techniques devised，a power cell based on this process could one day be as compact as household batteries．