A fast and cheap method for the analysis of macronutrients (K, P, Mg and Ca) in leaves of crop plants (wheat, poppy, barley and rape) using double pulse laser induced breakdown spectrometry (LIBS) is suggested. A commercially available LIBS spectrometer was calibrated with the aid of authentic plant samples previously analysed by AAS and ICP-OES after microwave digestion. The concentration ranges of K, P, Mg and Ca in the calibration standards were 30–66; 2.8–6.6; 1.0–5.6 and 6–24 g kg⁻¹, respectively. Cryogenic grinding and powder pressing to pellets were used as sample preparation steps. Obtained LIBS/ICP-OES recovery values for authentic crop plant samples were 93–109% (K); 93–114% (P); 89–109% (Mg) and 94–110% (Ca). Six certified reference materials (CRMs) of plant tissues were used for the LIBS method validation. Recovery values of 96–101% were obtained for K and P, when the certified concentration of the element in the CRM was inside the concentration range of the used calibration standards. Substantial matrix differences of the CRMs and LIBS calibration standards seem to be a probable reason for the worse recovery results (58–99%) obtained for Mg and Ca.

The microstructural evolution in Fe – Al – Ta alloys containing 23 – 31 at.% Al and 1.5 – 2.2 at.% Ta has been studied in the temperature range 650 – 750 °C by annealing for 1, 10, 100 and 1 000 h. The experiments confirm that in this temperature range the precipitation of the stable hexagonal C14 Laves phase is preceded by formation of coherent, metastable L2₁ Heusler phase precipitates within the Fe – Al matrix. However, precipitates of C14 are observed after much shorter annealing times than previously assumed. Creep strength increases substantially with increasing Al content of the alloys because the solid solubility for Ta in the Fe – Al matrix increases with increasing Al content and solid-solution hardening contributes substantially to the observed high creep strength. It may therefore be that the microstructural changes during creep have no noticeable effect on creep strength.

A method for the analysis of chromium in wool fabric samples was developed. It is fast and cheap with no sample preparation. This method involved the use of double pulse Laser Induced Breakdown Spectrometry (LIBS) for the wool fabric samples dyed by two types of metal complex dyes (C.I. Acid Orange 173 and C.I. Acid Black 60). A commercially available LIBS spectrometer was calibrated with the aid of authentic wool fabric samples previously analysed by F-AAS after microwave digestion. Comparable results can be obtained using this unique procedure if the same set of standards is used for XRF and LIBS calibration. Limits of detection for chromium achieved by suggested LIBS methods (from 5 to 10 mg kg⁻¹) are comparable with the WD XRF ones (from 4 to 5 mg kg⁻¹).

This paper describes the structure and properties of cast Fe₃Al-based alloy doped with 15 at. % of silicon and 2 at. % of molybdenum. The higher content of silicon is useful for the enhancement of high-temperature mechanical properties or corrosion resistance of iron aluminides but deteriorates their workability due to increased brittleness. It was found that the presence of both alloying elements leads to an increase of values of the high-temperature yield stress in compression. The heat treatment (annealing at 800 °C for 100 h) used for the achievement of phase stability causes the grain coarsening, so the values of the high-temperature yield stress in compression are lower at 600 °C and 700 °C in comparison to values measured for the as-cast state. This stabilization annealing significantly improves the workability/machinability of alloy. Furthermore, the higher silicon content positively affects the values of the thermal expansion coefficient that was found to be lower in the temperature range up to 600 °C compared to alloys with lower content of silicon.