  The electron cloud effect (ECE) causes beam instabilities in accelerator
structures with intense positively charged bunched beams. Reduction of the
secondary electron yield (SEY) of the beam pipe inner wall is effective in
controlling cloud formation. We summarize SEY results obtained from flat TiN,
TiZrV and Al surfaces carried out in a laboratory environment. SEY was measured
after thermal conditioning, as well as after low energy, less than 300 eV,
particle exposure.
