Abstract: This invention is a catalyst for treating the exhaust gases produced during lean-burn engine operation, the gases comprising nitrogen oxides, carbon monoxide and hydrocarbons. The catalyst comprises a support material comprising gamma-alumina, a layer of about 0.01 to 1.5 wt. % tungsten deposited onto the support followed by a layer of about 1 to 3 wt. % silver, both being individually based on the weight of the support material.

Abstract: An essentially neutral pH vehicle wheel cleaner for coated alloy vehicle wheels includes a builder, a surfactant, a buffer, a clarifier or mild abrasive, and a fragrance in water. The builder and surfactant interact to produce strong buffering to prevent a significant change in pH due to alkaline brake dust, road soil, and acidic road salts. A preferred embodiment utilizes tetrapotassium pyrophosphate as the builder, a sodium salt of sulfonated oleic acid as the buffer, and a ethylene oxide adduct of octylphenol as the surfactant. Various fragrances are disclosed.