"false" . "\"Mass fraction\" is used in the construction \"mass_fraction_of_X_in_Y\", where X is a material constituent of Y. It means the ratio of the mass of X to the mass of Y (including X). A chemical or biological species denoted by X may be described by a single term such as \"nitrogen\" or a phrase such as \"nox_expressed_as_nitrogen\". The chemical formula for isoprene is CH2=C(CH3)CH=CH2. The IUPAC name for isoprene is 2-methylbuta-1,3-diene. Isoprene is a member of the group of hydrocarbons known as terpenes. There are standard names for the terpene group as well as for some of the individual species."@en . . . "2019-05-14 17:27:20.0" . "mass_fraction_of_isoprene_in_air"@en . "SDN:P07::CF12N389" . . . "2019-05-14 17:27:20.0" . . . . "SDN:P07::CF12N389" . "3" . . . "" . "accepted"@en . "SDN:P07::CF12N389" . "3" . .