When you search for science information at ScienceAccelerator.gov [2], you get lots of help homing in on the research you need. Enter your search term, such as "fuel cell," and it will automatically generate a cluster field on the left column of your search results page. Topics appear such as "fuel cell vehicle," "solid oxide fuel," "fuel stack," and many more important related subjects. Date clusters also appear. For your convenience, the number of search results found on each topic or date will show up in parentheses. You just select the topic or date and your search continues to drill down to the information you need. ScienceAccelerator.gov finds information from 13 key DOE databases of scientific and technical information [3] and is developed and hosted at OSTI [4].
Links:
[1] http://www.osti.gov/ostiblog/users/admin
[2] http://www.scienceaccelerator.gov/
[3] http://www.scienceaccelerator.gov/resourcedescriptions
[4] http://www.osti.gov/