- promoter
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/preuh moh"teuhr/, n.1. a person or thing that promotes, furthers, or encourages.2. a person who initiates or takes part in the organizing of a company, development of a project, etc.3. a person who organizes and provides financial backing for a sporting event or entertainment.4. Chem. any substance that in small amounts is capable of increasing the activity of a catalyst.5. Also called collector. Metall. a water-repellent reagent enhancing the ability of certain ores to float so that they can be extracted by the flotation process.6. Genetics.a. a site on a DNA molecule at which RNA polymerase binds and initiates transcription.b. a gene sequence that activates transcription.7. Obs. an informer.[1400-50; late ME; see PROMOTE, -ER1; r. earlier promotour < AF]
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in chemistry, substance added to a solid catalyst to improve its performance in a chemical reaction. By itself the promoter has little or no catalytic effect. Some promoters interact with active components of catalysts and thereby alter their chemical effect on the catalyzed substance. The interaction may cause changes in the electronic or crystal structures of the active solid component. Commonly used promoters are metallic ions incorporated into metals and metallic oxide catalysts, reducing and oxidizing gases or liquids, and acids and bases added during the reaction or to the catalysts before being used.* * *
Universalium. 2010.
