. "SDN:P07::CF12N260" . . "SDN:P07::CF12N260" . . "false" . "SDN:P07::CF12N260" . "" . "accepted"@en . "mass_concentration_of_gaseous_elemental_mercury_in_air"@en . . "2009-07-06 15:41:29.0" . . "Mass concentration means mass per unit volume and is used in the construction mass_concentration_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'. The chemical symbol for mercury is Hg."@en . "1" . "1" . . "2009-07-06 15:41:29.0" . .