brain drain. brain drain. LINK / CITE ADD TO WORD LIST. noun. The definition of brain drain refers to a situation where all or the majority of intelligent, skilled or capable resources within a given field or geographic region leave the area because of various factors including lack of high paying jobs.
Alkylation is an important source for octane in gasoline. Source: Occupational Safety and Health Administration. Alkylation (al-kuh-ley-shun) is a secondary refinery unit operation that many refineries in the United States have because it adds high octane hydrocarbons to motor and aviation gasoline. High octane hydrocarbons are needed to help prevent autoignition of gasoline (knocking) in an engine and to meet recommended engine octane ratings.
In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbonâcarbon triple bond between two carbon atoms.lkynes occur in some pharmaceuticals, including the contraceptive norethynodrel. A carbonâcarbon triple bond is also present in marketed drugs such as the antiretroviral Efavirenz and the antifungal Terbinafine. Molecules called ene-diynes feature a ring containing an alkene (ene) between two alkyne groups (diyne).