{HEAD ~ Catalysts} employing the particles as a support and having {TAIL ~ catalytic agents} distributed at controlled depths in the particle have excellent initial and sustained activity and durability, especially for eliminating pollutants in automotive exhaust streams 
having
{ HEAD ~ Catalysts } employing the particles as a support and having { TAIL ~ catalytic agents } distributed at controlled depths in the particle have excellent initial and sustained activity and durability , especially for eliminating pollutants in automotive exhaust streams
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH