== EGR vacuum switching valve == Despite the rather lengthy name the EGR-VSV (exhaust gas recirculation vacuum switching valve) does little more than allow vacuum to flow through the system depending on engine coolant temperature.
A double bond in chemistry is a chemical bond between two chemical elements involving four bonding electrons instead of the usual two. The most common double bond, that is between two carbon atoms, can be found in alkenes. Many types of double bonds exist between two different elements. For example, in a carbonyl group with a carbon atom and an oxygen atom. Other common double bonds are found in azo compounds (N=N), imines (C=N) and sulfoxides (S=O).
metallic bond-a chemical bond in which electrons are shared over many nuclei and electronic conduction occurs. peptide bond, peptide linkage-the primary linkage of all protein structures; the chemical bond between the carboxyl groups and amino groups that unites a peptide.ttraction, attractive force-the force by which one object attracts another. covalent bond-a chemical bond that involves sharing a pair of electrons between atoms in a molecule. cross-link, cross-linkage-a side bond that links two adjacent chains of atoms in a complex molecule.