free-radical-chain mechanism
41elastomer — elastomeric /i las teuh mer ik/, adj. /i las teuh meuhr/, n. Chem. an elastic substance occurring naturally, as natural rubber, or produced synthetically, as butyl rubber or neoprene. [1935 40; ELAST(IC) + O + Gk méros a part] * * * ▪ chemical… …
42Desulfonylation reactions — are chemical reactions leading to the removal of a sulfonyl group from organic compounds. As the sulfonyl functional group is electron withdrawing, methods for cleaving the sulfur carbon bonds of sulfones are typically reductive in nature.… …
43Oxidative stress — represents an imbalance between the production and manifestation of reactive oxygen species and a biological system s ability to readily detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal redox state …
44Photo-oxidation of polymers — Photo oxidation is the oxidation of a polymer surface in the presence of oxygen or ozone that is facilitated radiant energy such as UV or artificial light. This proces is often the the most significant component of weather degradation of polymers …
45Vitamin C — This article is about ascorbic acid as a nutrient; for its chemical properties, see the article ascorbic acid; for other uses, see the disambiguation page. Vitamin C …
46Coenzyme Q10 — IUPAC name 2 [(2E,6E,10E,14E,18E,22E,26E,30E,34E) 3,7,11,15,19,23,27,31,35,39 …
47Metalloprotein — The structure of hemoglobin. The heme cofactor, containing iron, shown in green. Metalloprotein is a generic term for a protein that contains a metal ion cofactor.[1] Metalloproteins have many different functions in cells …
48Reactive oxygen species — (ROS) are ions or very small molecules that include oxygen ions, free radicals, and peroxides, both inorganic and organic. They are highly reactive due to the presence of unpaired valence shell electrons.ROS form as a natural byproduct of the… …
49catalysis — catalytic /kat l it ik/, adj., n. catalytical, adj. catalytically, adv. /keuh tal euh sis/, n., pl. catalyses / seez /. 1. Chem. the causing or accelerating of a chemical change by the addition of a catalyst. 2. an action between two or more… …
50petroleum refining — Introduction conversion of crude oil into useful products. History Distillation of kerosene and naphtha The refining of crude petroleum owes its origin to the successful drilling of the first oil well in Titusville, Pa., in 1859. Prior to… …
