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.
Alkylating Agents. Alkylating agents were one of the earliest classes of drugs used to treat cancer, beginning in the 1940âs. The biggest weakness of most cancer cells is that they are very sensitive to DNA damage. Alkylating agents work by reacting with the proteins that bond together to form the very delicate double helix structure of a DNA molecule, adding an alkyl group to some or all of them.