An open-to-air type electrolyte cathode discharge (ELCAD) has been developed with a new design. The present configuration leads to a stable plasma even at low flow rates (0.96 mL/min). Plasma fluctuations arising from the variations in the gap between solid anode and liquid cathode were eliminated by providing a V-groove to the liquid glass-capillary. Cathode (ground) connection is given to the solution at the V-groove itself. Interfaced to atomic emission spectrometry (AES), its analytical performance is evaluated. The optimized molarity of the solution is 0.2 M. The analytical response curves for Ca, Cu, Cd, Pb, Hg, Fe, and Zn demonstrated good linearity. The limit of detections of Ca, Cu, Cd, Pb, Hg, Fe, and Zn are determined to be 17, 11, 5, 45, 15, 28, and 3 ng mL(-1). At an integration time of 0.3 s, the relative standard deviation (RSD) values of the acid blank solutions are found to be less than 10% for the elements Ca, Cu, Cd, Hg, Fe, and Zn and 18% for Pb. The method is applied for the determination of the elemental constituents in different matrix materials such as tuna fish (IAEA-350), oyster tissue (NIST SRM 1566a), and coal fly ash (CFA SRM 1633b). The obtained results are in good agreement with the certified values. The accuracy is found to be between 7% and 0.6% for major to trace levels of constituent elements and the precision between 11% and 0.6%. For the injection of 100 microL of 200 ng mL(-1) mercury solution at the flow rate of 0.8 mL/min, the flow injection studies resulted in the relative standard deviation (RSD) of 8%, concentration detection limit of 10 ng/mL, and mass detection limit of 1 ng for mercury.

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An electrolyte cathode discharge atomic emission spectrometry (ELCAD-AES) method using formic acid is described for the determination of major to trace level of the elements Ni, Co, Fe, Mn, Mg, Cu, Cr, Pb, Ca in Zircaloys. The influence of HCOOH and CH 3 COOH to improve the sensitivity of ELCAD-AES for analyte determination is investigated. Sensitivity of ELCAD-AES was significantly improved with HCOOH for the determination of these elements. 20% (v/v) HCOOH was found to produce a maximum enhancement in the sensitivity of ELCAD-AES for the analytes. With 20% (v/v) HCOOH, improved detection limits were determined for Ni (5 ng mL À1 ), Co (9 ng mL À1 ), Fe (16 ng mL À1 ), Mn (7 ng mL À1 ), Mg (5 ng mL À1 ), Cu (6 ng mL À1 ), Cr (65 ng mL À1 ), Pb (10 ng mL À1 ), and Ca (8 ng mL À1 ). The improvement is 2-fold for most elements, 5-fold for Pb, and essentially unchanged for Cr. The use of HCOOH enabled the direct determination of analytes in Zircaloys by ELCAD-AES. The method has been validated by determining the concentrations of analytes Ni, Co, Fe, Mn, Mg, Cu, Cr, Pb, Ca in a Zircaloy certified reference material (Zircaloy-4 NIST-360b) and also in a Zircaloy sample which was analysed by glow discharge quadrupole mass spectrometer (GD-QMS). The precision expressed as a percentage relative standard deviation of signals of multiple analyses (N ¼ 4) of the ELCAD-AES method was found to be between 2 and 10% for major (>0.1 wt%) and minor level (<0.1 wt% and >100 mg g À1 ) elements and 10-15% for trace level (<100 mg g À1 and >10 ng g À1 ) elements. Depending on the levels of the impurities the relative error in accuracy of the ELCAD-AES method was found to be between 3 and 20%.