The role of neutron activation analysis in the development and certification of nist environmental standard reference materials

摘要

Neutron activation analysis (NAA) often plays an important role in the certification of inorganic constituents in many environmental standard reference materials (SRMs) in view of its accuracy, multi-elemental capability, ability to assess homogeneity, high sensitivity for many elements and essentially blank free nature. In addition, instrumental neutron activation analysis (INAA) requires no chemical dissolution prior to analysis, unlike most other analytical techniques. Since the concentration of an element certified in a National Institute of Standards and Technology SRM is usually determined by at least two independent analytical methods, the use of INAA as one method eliminates the possibility of common error sources resulting from sample dissolution. INAA also possesses the ability to assess the level of inhomogeneity of a material. The paper briefly highlights the role that NAA has played in the certification of recent environmental SRMs.