My mother's brown eyes, lost in a face that was decaying away.

Virtually all of the iodine 131 has now decayed away.

"It's in the groundwater, but not moving fast enough to get to site boundaries before it has long since decayed away."

Most of the lagging had decayed and fallen away.

As this substances decays away to become a stable nuclei rapidly, due to its short half life of 8.02 days.

So ancient was it that all the inside had in the course of ages decayed away, leaving nothing but a shell of bark.

The engulfed material eventually burns or decays away, but ends up leaving a hollow space with the original shape.

For ages the black hole engineers had struggled to maintain their Cities, to gather more material to replace what decayed away.

It has all decayed away to nothing.

Many of the radionuclides with shorter half-lives, such as strontium m-90 have now largely decayed away.