Perhaps you should try some spelling variations:
"particle acceleration" » "particle accelerators"
"partially accelerated" » "partially correlated", "partially integrated", "naturally accelerate"
"particle accelerator" » "particle accelerators"
"particle accelerate" » "particles accelerated", "particle acceleraton", "particle accelerators"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("particle accelerator") OR ("particle acceleration"))) OR ((("particle accelerate") OR ("partially accelerated")))).
• Removing quotes may allow a broader search: (((( particle accelerator ) or ( particle acceleration ))) or ((( particle accelerate ) or ( partially accelerated )))).
• Adding a wildcard symbol may retrieve word variants: (((("particle accelerator") or ("particle acceleration"))) or ((("particle accelerate") or ("partially accelerated"))))*.