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Abstract For a first-of-a-kind nuclear fusion reactor like ITER, remote maintainability of neutron-activated and contaminated components is one of the key aspects of plant design and operations, hence a fundamental ingredient of its success, as well as of the demonstration of long-term viability of fusion as an energy source. The whole ITER Remote Maintenance System (IRMS) is of unprecedented complexity and includes specifically developed technologies. Its procurement and start of operation will represent a major innovation to maintenance in hostile environments. Europe is a key contributor, with three remote handling (RH) systems, a.k.a. packages, plus a robotic inspection and metrology tool, currently under design. This paper gives an update on the status of design and procurement activities related to the IRMS. It will first introduce some key aspects of the reactor remote maintainability, and then give an overview of the present configuration of the global system. After this, the scope, status and challenges of the European (EU) packages will be illustrated in more detail, together with some key technological developments. Finally, the way all these efforts are coordinated will be presented together with the overall implementation scenario and milestones, and the way they fit with ITER construction and operation.

Abstract Differences in ash behavior during hydrothermal treatment were identified based on multivariate data analysis of literature information on 29 different feedstock. In addition, the solubility of individual elements was evaluated based on a smaller data set. As a result two different groups were distinguished based on char ash content and ash yield. Virgin terrestrial and aquatic biomass, such as different types of wood and algae, in addition to herbaceous and agricultural biomass, bark, brewer’s spent grain, compost and faecal waste showed lower char ash content than municipal solid wastes, anaerobic digestion residues and municipal and industrial sludge. Lower char ash content also correlated with lower ash yield indicating differences in chemical composition and ash solubility. Further evaluation of available data showed that ash in industrial sludge mainly contained anthropogenic Al, Fe and P or Ca and Si with low solubility during hydrothermal treatment. Char from corn stover, miscanthus, switch grass, rice hulls, olive, artichoke and orange wastes and empty fruit bunch had generally higher contents of K, Mg, S and Si than industrial sludge although differences existed within the group. In the future information on ash behavior should be used for enhancing the fuel properties of char based on feedstock type and hydrothermal treatment conditions.

We have measured the neutron capture cross sections of the stable magnesium isotopes 24,25,26Mg in the energy range of interest to the s process using the neutron time-of-flight facility n_TOF at CERN. Capture events from a natural metal sample and from samples enriched in 25Mg and 26Mg were recorded using the total energy method based on C6 2H6 detectors. Neutron resonance parameters were extracted by a simultaneous resonance shape analysis of the present capture data and existing transmission data on a natural isotopic sample. Maxwellian-averaged capture cross sections for the three isotopes were calculated up to thermal energies of 100 keV and their impact on s-process analyses was investigated. At 30 keV the new values of the stellar cross section for 24Mg, 25Mg, and 26Mg are 3.8±0.2 mb, 4.1±0.6 mb, and 0.14±0.01 mb, respectively.

The importance of improving the accuracy on the capture cross-section of $^{238}$U has been addressed by the Nuclear Energy Agency, since its uncertainty significantly affects the uncertainties of key design parameters for both fast and thermal nuclear reactors. Within the 7th framework programme ANDES of the European Commission three different measurements have been carried out with the aim of providing the $^{238} \text{U(n,}\gamma)$ cross-section with an accuracy which varies from 1 to 5%, depending on the energy range. Hereby the final results of the measurement performed at the n_TOF CERN facility in a wide energy range from 1 eV to 700 keV will be presented. International audience