Chemical Sensors -- See Chemical detectors Here are entered works on apparatus used to detect the presence or absence of chemicals on a relatively gross scale in industrial processes, environmental protection, etc.
Chemical Speciation -- See Speciation (Chemistry) Here are entered works on the determination of the various physico-chemical forms or species of chemicals present in environmental samples and the description of their distribution and transformation, particularly those species which are biologically active. --subdivision Speciation under individual chemicals and groups of chemicals, e.g. Copper--Speciation; Trace elements--Speciation