Atmospheric pressure active nitrogen (APAN) - a new source for analytical emission spectroscopy

摘要

An atmospheric pressure active nitrogen (APAN) afterglow was generated in pure flowing nitrogen (\u3c 10 ppm O(,2)) excited in an electrodeless ozonizer discharge. The afterglow, which contains several metastable species, has been observed to be an efficient source for the excitation of atomic and molecular emission. The application of the APAN afterglow for the detection and determination of trace levels of Hg and the volatile hydride forming elements, As, Bi, Ge, Pb, Sb, Se, Sn, and Te is documented. The analytical potential of utilizing molecular emission observed from gaseous Cl, Br, I, B, S, and P compounds was evaluated;The APAN afterglow has also been evaluated as a selective detector for gas chromatography (GC). Selective detection for organo-Hg, Pb, and Sn species at trace levels has been achieved. The GC-APAN system has also been observed to be a nonselective detector for organic molecules at nanogram levels through the detection of CN (B(\u272)(SIGMA)(\u27+)) emission at 388.3 nm. The GC-APAN system was specifically applied for the determination of ultratrace levels of methylmercury in fish, water, urine, and sediments, and diorganomercury compounds in water;The origin of the reactive species present in the afterglow andthe possible interactions which result in emission from speciesintroduced into the afterglow are discussed. Objectives for future;research are also considered;(\u27(DAG))DOE Report IS-T-965. This work was performed under ContractW-7405-eng-82 with the Department of Energy.