As far as the tile roofs, they last a long time. It isn't the tile that is the issue, it's the felt (or paper) underneath that gets replaced. Mine is 25 years old, has not been replaced yet. Some neighbors have had theirs redone, but many have not as yet. 04-06-2011, 12:00 AM.
Smaller particle accelerators are used in a wide variety of applications, including particle therapy for oncological purposes, radioisotope production for medical diagnostics, ion implanters for manufacture of semiconductors, and accelerator mass spectrometers for measurements of rare isotopes such as radiocarbon.
The Van de Graaff generator was developed as a particle accelerator for physics research, its high potential is used to accelerate subatomic particles to great speeds in an evacuated tube. It was the most powerful type of accelerator of the 1930s until the cyclotron was developed.