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This work aims at evaluating the applicability of photocatalytic oxidation (PCO) for industrial emission treatment. A dedicated single-pass semi-industrial PCO reactor is designed and the PCO removal of isopropanol (IPA) is investigated under industrial conditions: (i) high IPA concentrations ranging from 1.8 to 14.6 ppm and (ii) high air flow rates ranging from 26 to 146 m 3 .h −1 . The concentrations of upstream and downstream IPA and by-products are monitored, not only using analytical instruments (mass spectrometry), but also gas micro-sensors. This approach aims at assessing the aptitude of commercially available micro-sensors to monitor a semi-industrial PCO reactor, and estimating their ability to automate such a process for industry. First, the influence of the main process parameters has been addressed: (i) IPA concentration, (ii) total air flow rate, (iii) number of PCO stages and (iv) number of PCO media. Irrespectively of the process condition, IPA PCO does not lead to deactivation of the media; whereas IPA mineralization and side-products formation are directly impacted by the process parameters. The increase of IPA concentration and air flow rate inhibits IPA mineralization, while the increase of number of stages and media promotes IPA mineralization. It is evidenced that selected gas micro-sensors can provide a semi-quantitative monitoring of the process performances. The main limitations of sensors are (i) their resolution regarding the detection of concentration variations and (ii) their cross-sensitivity to various classes of VOCs. Nevertheless, some sensors could be relevant for the automation and control of the PCO process once a preliminary metrological validation with relevant analytical devices is performed. [ABSTRACT FROM AUTHOR]

The exact nature of the lowest Kμ = 2+ rotational bands in all deformed nuclei remains obscure. Traditionally they are assumed to be collective vibrations of the nuclear shape in the y degree of freedom perpendicular to the nuclear symmetry axis. Very few such γ bands have been traced past the usual backbending rotational alignments of high- j nucléons. We have investigated the structure of positive-parity bands in the N = 90 nucleus 156Dy, using the 148Nd(12C,4n) 156Dy reaction at 65 MeV, observing the resulting y-ray transitions with the Gammasphere array. The even- and odd-spin members of the Kμ = 2+γ band are observed up to 32+ and 31+, respectively. This rotational band faithfully tracks the ground-state configuration to the highest spins. The members of a possible γ vibration built on the aligned yrast S band are observed up to spins 28+ and 27+. An even-spin positive-parity band, observed up to spin 24+, is a candidate for an aligned S band built on the seniority-zero configuration of the 0+2 state at 676 keV. The crossing of this band with the 0+2 band is at ħωc = 0.28(1) MeV and is consistent with the configuration of the 0+2 band not producing any blocking of the monopole pairing. [ABSTRACT FROM AUTHOR]