Helium gas evolved from alpha particles can accumulate within the crystals which cause them to weaken and rupture.
Over time, particles will accumulate between the sand grains in the filter.
The reason that the particles and dust accumulated together is their gravitational attraction for each other.
If a magnet were dipped in the resulting solution, no particles of iron would accumulate on it.
The charged particles then accumulate on a series of flat plates called a collector that is oppositely charged.
The filters actually work better as the particles accumulate because they close the gaps in the mesh.
Some pigment migrates from a tattoo site to lymph nodes, where large particles may accumulate.
The housing must periodically be cleaned, or the particles will accumulate to such a thickness as to stop the drum rotating.
"The particles may accumulate faster as the attracting surface increases in size, Dad," Tom pointed out.
After a while, when more and more fluid has passed the stripes, particles accumulate and the stripe-area changes color.