Here's one I think was missed back in March (I don't remember seeing it in the news, either).
Frank Sherwood Rowland died on March 10, 2012, at age 84. He was best known for work on CFCs and their effects on the earth's ozone layer, and he was very influential in shaping public policy to reduce and regulate the use of CFCs. For his work, he shared the 1995 Nobel Prize in Chemistry.