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The design of new generation fast nuclear reactors requires highly accurate cross-section measurements in the MeV energy region. The 242Pu fission cross section is of particular interest for Pu incineration and nuclear waste production. There are discrepancies around 1 MeV incident neutron energy between libraries and among experimental data. Some data suggest the presence of a strong structure between 1 and 1.2 MeV whereas it is barely visible on some other data and its shape is very different among evaluations. The large majority of the 242Pu(n,f) measurements have been carried out with respect to the 235U(n,f) secondary-standard cross section. This introduces a strong correlation between measurements from different research teams. Moreover, this reference cross section exhibits structures, in particular a steep increase of +10% at 1 MeV. Therefore, we aim to re-measure the 242Pu(n,f) cross section relative to the primary-standard 1H(n,n)p cross section, by using a proton recoil detector. This standard has a very high accuracy (0.4%), is not used for other 242Pu measurements, and is structureless. An experiment has been carried out in October 2022 at the MONNET facility in JRC Geel, with incident neutron energies from 0.9 MeV to 2.0 MeV. The experimental setup will be presented, and the analysis procedure will be detailed. [ABSTRACT FROM AUTHOR]

The acceleration of the global production and consumption of electronic devices and the concerns related to waste electrical and electronic equipment (WEEE) motivated this research. Printed circuit boards (PCB) can be found in almost all types of electronic devices, and their composition contains heavy metals that can cause environmental impacts due to improper disposal. However, on the other hand, there are elements with added value, such as copper, gold, silver, iron, aluminum and other critical raw materials, such as tantalum, that can be recovered. Metal recovery can conserve natural resources since it prevents new minerals from being extracted, being a great contribution to the circular economy. In this research, the PCB element composition was initially determined through the scanning electron microscope analysis. Then, the PCB was shredded in a cutting mill and classified in grain size classes by sieving. Afterwards, magnetic separation has been performed together with gravity and electrostatic separation of the non-magnetic fraction. In gravity separation, the metal recovery was satisfactory for the particle size −0.6 + 0.3 mm and for the particle size −1.18 + 0.6 mm. In electrostatic separation, the efficiencies obtained were higher for the smaller particle size (−0.3 mm). [ABSTRACT FROM AUTHOR]

In the quarry sector, the reduction of landfill material may be obtained not only by finding a suitable recovery of the material as a by-product, but also by identifying the best available cutting technique to be used on the basis of the physical, chemical, and mechanical characteristics of the stones. The choice of the best cutting technique could lead to high efficiency and performance, high quality of the cut surfaces, and a very low environmental impact by reducing energy consumption, decreasing the concentration of heavy metals in the sludge, and producing less waste. In this context, an analysis of the procedures for cutting different types of ornamental stones into slabs together with the evaluation of sludge production for the different cutting methods has been carried out. Two types of analysis were carried out in parallel: evaluation of the stones workability and calculation of the amount of sludge produced in the three different cutting technologies and from the cutting of blocks. A comparison was carried out on the quality of the sludge produced, on type and quantity of metals present, taking into account the different cutting technologies. The performed tests were: chemical analysis, magnetic separation test, and SEM analysis of the metal fraction. The study could provide stone producers with a technological, scientific instrument to identify the best cutting techniques for the processing of their stones, in order to obtain a high-efficiency process, optimize the recovery process, increase the economic advantages, and evaluate the possible reuse of the sludge through a proactive waste management strategy. [ABSTRACT FROM AUTHOR]

Since its introduction in the seventies', the so-called surrogate-reaction method (SRM) has motivated the development and improvement of theories in connection to direct reactions. A recent work by Bouland and Noguère, Phys. Rev. C 102, 054608 (2020), has shown that the inclusion of experimental probabilities in the neutron cross section evaluation process can be better achieved using tools resulting from the efforts made over the two last decades. In particular, the authors have put forward a new prescription, named after the SRM as extended SRM (ESRM), to convert, with reasonable confidence, probabilities measured in direct reactions to pseudo-experimental neutron-induced reaction cross sections. Applied to the 174Yb(3He,py)176Lu* transfer reaction, the ESRM has demonstrated much more precision than the early use of the SRM. In addition to the 'direct' analysis of reaction probabilities measured in direct reactions using the right modeling as developed in Phys. Rev. C 100, 064611 (2019), it is worth to try converting the measured probabilities in pseudo experimental neutron-induced cross sections for neutron reactor data applications. In the present paper, first results, before conversion, are shown by applying the two ESRM equations to a fissile isotope. [ABSTRACT FROM AUTHOR]