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Ruthenium is a chemical element with symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table
R 0541 (OTTO) Ruthenium powder, -200 mesh, 99.95% Cas 7440-18-8 - used for cathodic protection of underground and submerged structures, and for electrolytic cells for such processes as generating chlorine from salt water.