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Previous studies have revealed silica formation in the teeth of mandibular gnathobases of copepods while significant amounts of zinc and copper are present, which might improve mechanical stability of the teeth and represent an adaptation to compact food particles. The present study aimed at analysing the distribution and concentration of trace elements in the mandibular gnathobases of females of the Antarctic copepod species Calanoides acutus. Because of the low overall masses of few micrograms per specimen the application of a combination of position-resolved micro-beam techniques was necessary and micro-particle-induced X-ray emission spectrometry and laser ablation inductively coupled plasma mass spectrometry were used to determine Ba, Br, Ca, Cl, Cu, Fe, K, Mg, Na, Ni, P, S, Si and Zn in the samples with μm to sub-μm resolution. Calibration strategies were optimised to fit for the carbonate matrix. The analyses revealed a distinct enrichment of Br, Ca, Fe, K, S, Si and Zn in the teeth of the gnathobases.

The increasing demand for high purity battery elements and the necessity to reliably determine trace concentrations of impurity metals have triggered recent development of new analytical methods. Both in battery metal production and recycling there is a growing need for new fast, precise and easy-to-use analytical methods, especially for the on-line and on-site analysis of lithium salt solutions, whose derivative products are used in the battery industry. Typically used established techniques, such as ICP-OES or ICP-MS, are usually limited to laboratory use due to high plasma gas flow rates and power consumption, making them unsuitable for real-time analysis and monitoring of industrial processes on-site. Therefore, a fast and precise on-site method which allows trace element analysis would be preferable. Here we have investigated the potential of micro-discharge optical emission spectroscopy (μDOES) for the given challenge of on-line quantification of impurity metals in lithium matrices. The technology is based on a micro-plasma, which is directly created inside an aqueous sample without any carrier gas by using electrodes and high voltage pulses. In this study, the impurity elements Na, K, Al, Fe and Zn were simultaneously measured both in lithium carbonate and lithium hydroxide solutions. For this purpose, the lithium concentrations were varied between 0.3 and 2 mg L−1 and those of the contaminants between 0 and 50 μg L−1. Calibration series and long-term stability measurements were carried out, whereby various parameters such as the plasma discharge energy, signal integration setting and sample electrical conductivity were optimised. Micro-discharge optical emission spectroscopy proved to be useful for the fast and precise main component and trace analysis of saline solutions. A relative standard deviation of 3% was achieved for the lithium concentration in long-term measurements over 9 h. For the trace impurity metals (Na, K, Al, Fe, and Zn) high coefficients of determination (R2 > 0.99) and limits of detection in the low μg L−1-region, comparable to ICP-OES, were obtained. Multi-linear regression models were used to correct for cross-element correlations that may occur at increasing lithium concentrations due to ionisation effects. Industrial process samples were measured on-site and the results were validated using laboratory ICP-OES. [ABSTRACT FROM AUTHOR]

In this article a preparation method for reference materials containing trace amounts of metals is presented. The applicability is shown for spatial resolved techniques like μXRF and LA-ICP-MS, for a handheld system (handheld LIBS) and also for CμXRF which provides depth resolved information. The materials show excellent trace element homogeneities for spatial resolved measurements as well as for depth sensitive methods. This was demonstrated for Al, Ca, Cd, Co, Cr, Fe, La, Mg, Pb, Sr and Zn, which cover a wide range of different elemental properties. In addition, a sample containing four different elements was used to show that the preparation of multi element samples is possible with this preparation method. A sample series of seven samples with increasing iron content was generated to show the suitability of the prepared material as reference material for the calibration of the different analytical techniques. Due to the stackability of the obtained layers a wide range of applications for depth resolved measurements was opened. Therefore, the capability of the material as well as the performance of the CμXRF setup were shown by determining the depth profile of multiple layer systems containing 1000 mg kg−1 iron. [ABSTRACT FROM AUTHOR]

CIGS solar cells (CIGS: CuInSe2, doped with gallium) on flexible glass fibre substrates were investigated to determine a possible migration of compounds from the substrate through the back contact layer into the absorber layer. We employed laser ablation ICP-MS to perform depth profile analysis as this technique combines ease of sample preparation with high sensitivity and moderate depth resolution. Careful optimization of the fluence and repetition rate of the laser system was necessary to ensure sufficient depth resolution in order to be able to relate the transient signals to the different layers. The results show that apart from sodium and small amounts of titanium no elements have migrated into the absorber layer. This was confirmed by micro-PIXE measurements on cross sections of the cell. [ABSTRACT FROM AUTHOR]