. . "" . . "accepted"@en . "SDN:P07::7KBKC1NS" . . "2015-01-07 16:23:38.0" . "SDN:P07::7KBKC1NS" . . "2" . "SDN:P07::7KBKC1NS" . "false" . "mole_fraction_of_alkenes_in_air"@en . "2" . "Mole fraction is used in the construction \"mole_fraction_of_X_in_Y\", where X is a material constituent of Y. A chemical species denoted by X may be described by a single term such as \"nitrogen\" or a phrase such as \"nox_expressed_as_nitrogen\". Alkenes are unsaturated hydrocarbons as they contain chemical double bonds between adjacent carbon atoms. \"Hydrocarbon\" means a compound containing hydrogen and carbon. Alkenes contain only hydrogen and carbon combined in the general proportions C(n)H(2n); \"alkenes\" is the term used in standard names to describe the group of chemical species having this common structure that are represented within a given model. The list of individual species that are included in a quantity having a group chemical standard name can vary between models. Where possible, the data variable should be accompanied by a complete description of the species represented, for example, by using a comment attribute. Standard names exist for some individual alkene species, e.g., ethene and propene."@en . "2015-01-07 16:23:38.0" . . .