Traditionally, car tires have been filled with compressed air. Air is 78 percent nitrogen and just under 21 percent oxygen, ...

Guinness got closer in 1989 by affixing a nitrogen-filled plastic disk to the bottom of each can. But while this method was successful when the can was cold, warm beer tended to explode or overflow.

While some states have passed or are considering legislation to allow nitrogen gas executions, it is uncertain how widely the method will be used. Public support for the death penalty is declining ...