"\"Content\" indicates a quantity per unit area. The \"atmosphere content\" of a quantity refers to the vertical integral from the surface to the top of the atmosphere. For the content between specified levels in the atmosphere, standard names including content_of_atmosphere_layer are used. \"Nox\" means a combination of two radical species containing nitrogen and oxygen: NO+NO2. The phrase 'expressed_as' is used in the construction A_expressed_as_B, where B is a chemical constituent of A. It means that the quantity indicated by the standard name is calculated solely with respect to the B contained in A, neglecting all other chemical constituents of A."@en . . "SDN:P07::CF12N87" . . "1" . "atmosphere_mass_content_of_nox_expressed_as_nitrogen"@en . "1" . . "2009-07-06 15:41:29.0" . "SDN:P07::CF12N87" . . . . . "SDN:P07::CF12N87" . "2009-07-06 15:41:29.0" . "false" . . "" . "accepted"@en .