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Much has been documented worldwide on the implications of the passage of a tropical cyclone on a shelf ecosystem. In particular, wind mixing, resuspension and increased terrestrial runoff have thus far been pinpointed as the three major processes that bring about higher depth-integrated values of nutrients, chlorophyll a, primary and bacterial production, particulate organic carbon and nitrogen concentrations as well as biomass in the water column. Here, however, there is evidence to indicate that the cross-shelf upwelling of nutrient-rich subsurface Kuroshio water likely increased significantly after the passage of typhoon Herb in a normally downwelling region northwest of Taiwan. This phenomenon, most probably due to an enhanced buoyancy effect resulting from excessive rainfall, offers the best explanation for the lower temperatures yet higher salinity and larger amounts of nutrients that were observed in the deep and bottom coastal waters after the typhoon in July 1996. Further, there are indications that the episodic event might have pushed the Kuroshio towards the shelf-break, which then facilitated the onshore transport of subsurface Kuroshio waters. These new sources of nutrients along with nutrients brought in by the increased terrestrial runoff would eventually mix in or upwell to the euphotic zone on the shelf, thereby supporting new production. D

In this review, the literature on the subject of electrothermal vaporization-inductively coupled plasmamass spectrometry (ETV-ICP-MS) published during the last decade is reviewed with a double purpose: an evaluation of the possibilities of this technique for dealing with very challenging analytical applications on the one hand, and the establishment of a reference guide for method development in ETV-ICP-MS on the other. First, a brief introduction, pointing out the milestones in the development of the technique will provide the reader with a better understanding of the present situation of ETV-ICP-MS and its future perspective. After a section on the basic processes occurring in the furnace and during analyte transport, a guide for method development for challenging analytical applications is proposed, based on the existing literature. Next, the latest contributions in the main application areas of the field are reviewed, with special attention to the most challenging ones: i.e. speciation, "thermal" resolution, enabling complex matrixes to be analyzed and spectral overlap to be avoided, and the direct analysis of slurries and solid samples. Finally, the advantages obtained by coupling an ETV unit to newer types of ICP-MS instrumentation, equipped with collision/reaction cells, time-of-flight (TOF) or sector field (SF) spectrometers, are also discussed.

The noble metals are currently receiving worldwide attention as they offer the dual attraction of rare, high-value noble metals as well as having important industrial uses. Accurate determination of noble metals and Au are important in some geological research programmes, where the noble metals (the platinum-group metals) provide a unique tool for deducing the history of Earth accretion and subsequent geological processes (Rehkämper and Halliday 1997, Reddi and Rao 1999). On the other hand, the introduction of Pt-, Pd-and Rh-containing catalytic converters in automobiles makes the noble metals a focus of attention in

In this work, an ordered mesoporous titania film was introduced to coat a capillary by means of sol-gel technique. Sol-gel titania coating was developed for the preconcentration/separation of trace V, Cr and Cu by capillary microextraction (CME), and the adsorbed analytes were eluted for electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) detection. By immobilizing sol-gel titania on the inner surface of a fused-silica microextraction capillary, the sol-gel titania coating was prepared easily. Its adsorption properties, stability and the factors affecting the adsorption behaviors of V, Cr and Cu were investigated in detail. At pH range of 7 to 9, the titania-coated capillary (50 cm ×0.25 mm) is selective towards V, Cr and Cu, and the target analytes could be desorbed quantitatively with 50 µl of 1.0 mol l −1 HNO 3 at the rate of 0.05 ml min −1. With a consumption of 2 ml sample solution, an enrichment factor of 33.3, and a detection limit (3 s) of 1.1 pg ml −1 (10.5 fg) for V; 3.3 pg ml −1 (33.0 fg) for Cr and 6.3 pg ml −1 (63.1 fg) for Cu respectively were obtained. The precisions Relative Standard Deviations (RSDs) for nine replicate measurements of 1 ng ml −1 V, Cr and Cu were 3.4, 5.1 and 6.4%, respectively. The proposed method has been applied to the determination of V, Cr and Cu in human urine and lake water, and the recoveries for these elements were 89.2∼105%. The developed method was also applied to the determination of the target elements in NIES No. 10-a (rice flour-unpolished) and NIES No. 9 (sargasso) certified reference materials, and the results found are in good agreement with the certified values.

A simple and selective method of flow injection (FI) using a micro-column packed with quinine modified resin as solid phase extractant has been developed for preconcentration and separation of trace amount of vanadium(V) and vanadium(IV) in water samples, followed by determination with fluorination assisted electrothermal vaporization (FETV)-inductively coupled plasma optical emission spectrometry (ICP-OES). At pH 3 ∼ 3.8, the modified resin is selective towards V(V) and almost not towards V(IV), while, V(IV) could be quantitatively adsorbed by the modified resin at pH 5 ∼ 7. The two vanadium species adsorbed by modified resin could be readily desorbed quantitatively with 0.3 ml of 0.5 mol l −1 HCl. Both vanadium species in elution were then determined by ETV-ICP-OES with the use of polytetrafluoroethylene (PTFE) as chemical modifier. Effects of acidity, sample flow rate, concentration of elution solution and interfering ions on the recovery of the analytes have been systematically investigated. Under the optimal conditions, the adsorption capacities of the quinine modified resin for V(V) and V(IV) are 7.6 and 8.0 mg g −1 , respectively. The detection limit (3σ) of V is 0.072 ng ml −1 for FETV-ICP-OES and 0.56 pg ml −1 for FETV-ICP-MS with enrichment factor of 62.5, and the relative standard deviation (R.S.D.) is 4.9% (n = 9, C = 0.2 g ml −1) and 3.8% (n = 9, C = 1.0 ng ml −1), respectively. The proposed method has been applied to the determination of trace V(V) and V(IV) in different water samples, and the recoveries of V(V) and V(IV) are 100 ± 10%. In order to further verify the accuracy of the developed method, FETV-ICP-MS was employed to analyze the vanadium species in water samples after separation/preconcentration, and analytical results are in good agreement with that obtained by the proposed method. The developed method was also applied to the analysis of the total V in GBW07401 soil certified reference material and in GBW07605 tea leaves certified reference material, and the determined values coincided with the certified values very well.