The degradation of biomass is studied in the ranges of 330-410 °C and 30-50 MPa and at 15 min of reaction time. To characterize the chemistry of biomass degradation, key compounds which are intermediates of the biomass degradation are identified and quantified. These key compounds are used to compare the results from earlier studies of model compounds such as, e.g., glucose or cellulose, with biomass degradation in order to identify chemical reaction pathways. Key compounds identified are phenols (phenol and cresols), furfurals, acids (acetic acid, formic acid, lactic acids, and levulinic acid), and aldehydes (acetic aldehyde and formic aldehyde). In addition, sum parameters such as the total organic carbon content and the composition of the formed gas phase are used to describe the biomass degradation. The results are compared with the hydrothermal upgrading process and with the well-known gas-phase gasification processes. The influence of the change of water properties from subcritical to supercritical conditions on the biomass degradation is also discussed. These comparisons show that most of the main reaction pathways detected by the key compounds can be understood by the studies of model compounds. On the other hand, biomass is much more complex because biomass contains a lot of different substances. Especially, the influence of salts is significant and, in addition, rather complex.

We report on the measurement of the ^{7}Be(n,p)^{7}Li cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n_TOF facility at CERN. This reaction plays a key role in the lithium yield of the big bang nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and they showed a large discrepancy between each other. The measurement was performed with a Si telescope and a high-purity sample produced by implantation of a ^{7}Be ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low energy, relative to current evaluations, in the region of BBN interest, the present results are consistent with the values inferred from the time-reversal ^{7}Li(p,n)^{7}Be reaction, thus yielding only a relatively minor improvement on the so-called cosmological lithium problem. The relevance of these results on the near-threshold neutron production in the p+^{7}Li reaction is also discussed.

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A new high flux experimental area has recently become operational at the n TOF facility at CERN. This new measuring station, n TOF-EAR2, is placed at the end of a vertical beam line at a distance of approximately 20 m from the spallation target. The characterization of the neutron beam, in terms of flux, spatial profile and resolution function, is of crucial importance for the feasibility study and data analysis of all measurements to be performed in the new area. In this paper, the measurement of the neutron flux, performed with different solid-state and gaseous detection systems, and using three neutronconverting reactions considered standard in different energy regions is reported. The results of the various measurements have been combined, yielding an evaluated neutron energy distribution in a wide energy range, from 2 meV to 100 MeV, with an accuracy ranging from 2%, at low energy, to 6% in the high-energy region. In addition, an absolute normalization of the n TOF-EAR2 neutron flux has been obtained by means of an activation measurement performed with 197 Au foils in the beam.

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