In the traditional chemical vapor generation system of KBH4 (or NaBH4)–Cd21–HCl in aqueous solution,volatile components containing cadmium species can be generated but with low efficiency. In this work, it wasfound for the first time that the efficiency for the generation of the cadmium-containing vapor was greatlyimproved when halogenate, i.e., NaBrO3 or NaIO3, was added. The chemically generated vapor was separatedfrom the reaction medium, and introduced into an atomic fluorescence spectrometer (AFS) with argon as thecarrier gas, for the atomization and detection of cadmium. The experimental conditions for the efficientgeneration of the cadmium-containing vapor were optimized and the limit of detection (LOD, 3s) was thenfound to be 10 pg mL21. This modified chemical vapor generation system is potentially cleaner, and could havewide applications for sample introduction and/or matrix separation in analytical atomic spectrometries, such asflame atomic absorption spectrometry (FAAS), electrothermal atomic absorption spectrometry (ETAAS),inductively coupled plasma atomic emission spectrometry (ICP-AES), ICP-MS (mass spectrometry), microwaveinduced plasma atomic emission spectrometry (MIP-AES) and MIP-MS for the determination of ultratracecadmium or some other elements.

Permanent chemical modifiers have been shown to prolong graphite tube lifetime while reducing the furnace cycle time, thus improving cost-effectiveness. In this work, iridium is used as a permanent chemical modifier for the first time in the determination of selenium by tungsten-coil atomic absorption spectrometry ŽW-Coil AAS.. The iridium modifier is thermally coated onto the tungsten coil. After coating, the coil can be used for 300-400 firings without further application of the modifier. Thermal treatment with iridium permits operating with higher pyrolysis temperature and coil lifetime is extended up to 1600 firings. The sensitivity and linearity of the method is improved, and the analytical procedure allows the use of analyte solutions containing up to 8% nitric acid. The short-term stability of the absorbance measurements is demonstrated by the reproducibility in the measurements of a Se amount 6ng. 30 times higher than the limit of detection Ž0.2 ng.. A 7% relative standard deviation ŽR.S.D.. was observed for 10 consecutive measurements of 6 ng Se. The long-term stability is almost as good: less than 9% R.S.D. over a 3-week period and 1500 firings. The surface of the tungsten-coil treated with iridium is examined before and after intensive use by scanning electron microscopy. Finally, the thermal treatment of the tungsten-coil with iridium appears to delay the appearance of selenium atoms by approximately 0.2 s although the integrated absorbance measurements are unaffected. The magnitude of delay decreases with coilage.

A pulsed (10 Hz) optical parametric oscillator (OPO) lasersystem based on