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The use of plasma atomic spectrometric methods for the analysis of high-purity refractory powders of Al2O3, SiC and ZrO2 used in the production of advanced ceramics is discussed. Special reference is given to the use of combined procedures including sample decomposition and in the case of ZrO2 to matrix removal as well as to the slurry technique as a direct method in atomic spectrometry with inductively coupled plasmas (ICP). Both the possibilities, limitations and analytical use of the slurry technique are discussed and shown to be related to the particle size of the powder; this should be below the 5–10 μm level. The use of a Simplex method for the optimization of the slurry technique towards obtaining both the highest power of detection and calibration using solutions will be treated for the case of SiC. A critical evaluation of the use of ICP atomic emission and of ICP mass spectrometry is presented.

The application of inductively coupled plasma optical emission spectrometry (ICP-OES) to the determination of boron was studied with regard to the optimization of boron neutron capture therapy (BNCT), a method used in cancer radiotherapy. In order to enable trace determinations of B in tissue down to the sub μg/g-level (as this application requires), the different parameters of ICP-OES (gas flow, power, observation height) were optimized towards highest power of detection. Two different nebulizers (Babington and Meinhard nebulizer) as well as ICPs with argon or nitrogen as outer gases were used. The optimization was carried out with the aid of a modified simplex. The lowest detection limit for B (25 ng/ml) is obtained in the case of a Babington nebulizer and with an ICP using Ar as outer gas as well as a forward power of 1.3 kW (plate voltage at the r.f. generator: 2.75 kV). Therefore, the nebulizer gas flow had to be set at 1.1 l/min (at 4.5 bar) and an intermediate gas flow of 5 l/min in the case of a Greenfield-type torch was required. After optimization the natural concentration of B in biological tissues (0.1–0.3 μg/g) could be determined after decomposition of 1–1.5 g of the sample with 5 ml HNO3 (63%) at high temperature and pressure during 2 h in closed PTFE vessels. Results obtained with spiked liver standards were precise (RSD 5%–8%) and accurate in a concentration range of 5 μg/g to 100 μg/g. The method developed could be satisfactorily used for the analysis of tissue samples of mice tumors. Furthermore, the uptake and metabolization of boron and its derivatives could be well monitored at the 1–5 μg/g level.

A study of prompt neutrino events from 400 GeV protons on a beam-dump is presented. The ratio of electron- to muon-neutrino rates is 0.86±0.14, in agreement withe−μ universality. The anti-neutrino to neutrino flux ratio is $$\bar v_\mu /v_\mu = 0.81 \pm 0.19$$ . The absolute rates and distributions observed are shown to be in quantitative agreement with the known properties of charmedquark production in hadron collisions.

Inclusive charged-current interactions of high-energy neutrinos and antineutrinos have been studied with high statistics in a counter experiment at the CERN Super Proton Synchrotron. The energy dependence of the total cross-sections, the longitudinal structure function, and the nucleon structure functionsF2,xF3, and\(\bar q^{\bar v} \) are determined from these data. The analysis of theQ2-dependence of the structure functions is used to test quantum chromodynamics, to determine the scale parameter Λ and the gluon distribution in the nucleon.

The cross section ratios of neutral and charged current interactions induced by neutrinos and antineutrinos in iron have been measured in the 200 GeV narrow-band beam at the CERN SPS. We findRv=0.301±0.007 andRv=0.363±0.015 for a hadron energy cut of 10 GeV. The results are in agreement with the standard model of electroweak interactions. In the\(\overline {MS} \) renormalization scheme at the scale of theW boson mass\(\sin ^2 \hat \theta _W \left( {m_W } \right) = 0.226 \pm 0.012\) is obtained, where the error represents the experimental uncertainty. The theoretical uncertainty is estimated to beΔsin2θW=±0.006.