Different amounts of degradation for n-Si and p-Si are observed after X-ray, H + , and He + irradiations. Recombination lifetime and forward I-V measurements made on abrupt-junction diodes are compared to theory. Ionizing damage and displacement damage associated with surface and bulk trapping mechanisms, respectively, compete with each other and lead to different behaviors according to the doping type of the silicon on the lightly doped side of the junction. Surface effects are dominant in the n + /p diodes compared to the p + /n diodes; bulk trapping prevails in the n-Si compared to p-Si. Independently of ion type or fluence, the lifetime damage factor due to irradiation is worse in the p-Si than in the n-Si by a factor of 2-3 times.

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Results are shown obtained in the optimization of an automatic flow injection system that combines microwave digestion with atomic spectrometric detection (FAAS, ICP/AES) for the determination of heavy metals in sewage sludge. Digestion is performed by preparing a suspension of the sample in 1.5 mol/l HNO(3) and making it flow through a PTFE capillary tube placed inside a conventional microwave oven. The effects of the length and inner diameter of the capillary tube, as well as that of the pumping rate, have been studied in order to find the experimental conditions that allow a quantitative elemental recovery in the shortest period of time possible. The optimization study was carried out on a certified sample (BCR No. 146), and the elements determined were Zn, Cu, Pb, Cd, Ni and Cr. The experimental data (percent recovery vs. digestion time) have been fitted to a mathematical model in order to quantify the influence of each of the variables studied. The optimized procedure (MW-ICP/AES) has been applied to one ordinary and one certified sewage sludge sample. In comparison with the conventional methods of sewage sludge analysis, the one proposed is less time consuming, while being equally precise and accurate.

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Nebulizers offer a wide range of applications in the field of analytical chemistry. This article is a general and comprehensive overview that addresses the most common principles of nebulization and their main and most recent applications in chemical analysis.

A new natural deep eutectic solvent (NADES)-based analytical method for mercury speciation in water samples is presented. A NADES (i.e., decanoic acid:DL-menthol in a molar ratio of 1:2) is used as an environmentally friendly extractant for separation and preconcentration using dispersive liquid–liquid microextraction before LC-UV–Vis. Under optimal extraction conditions (i.e., NADES volume, 50 µL; sample pH, 12; volume of the complexing agent, 100 µL; extraction time, 3 min; centrifugation speed, 3000 rpm; and centrifugation time, 3 min), the limit of detection values were 0.9 µg L−1 for the organomercurial species and 3 µg L−1 for Hg2+, which had a slightly higher value. The relative standard deviation (RSD, n = 6) has been evaluated at two concentration levels (25 and 50 µg L−1) obtaining values for all the mercury complexes within the range of 6–12% and 8–12%, respectively. The trueness of the methodology has been evaluated using five real water samples from four different sources (i.e., tap, river, lake, and wastewater). The recovery tests have been performed in triplicate obtaining relative recoveries between 75 and 118%, with RSD (n = 3) between 1 and 19%, for all the mercury complexes in surface water samples. However, wastewater sample showed a significant matrix effect (recoveries ranged between 45 and 110%), probably due to the high amount of organic matter. Finally, the greenness of the method has also been evaluated by the analytical greenness metric for sample preparation (i.e., AGREEprep). Graphical Abstract

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