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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]

We report the results of an experiment, realized with the EUROBALL IV spectrometer, in which superdeformed (SD) states have been populated in 197,198Pb nuclei. Crosstalk transitions between two signature partner SD bands in 197Pb have been observed with an established Mi character, giving access to the magnetic properties of the v[752]5/2 intruder orbital. Six new SD bands have been identified in 197,198Pb. The results are interpreted in the framework of cranked Hartree-Fock calculations. A mixing between quasi-particle excitations and an octupole vibration is suggested in the two SD isotopes. [ABSTRACT FROM AUTHOR]

Electromagnetic shielding effectiveness properties of polyaniline – polyurethane nanocomposites at microwave frequencies were studied. The conducting blends showed a very low percolation threshold and their electronic properties can be tuned easily with the mass fraction of polyaniline in the blends or through chemical process. Measurements on composite materials were performed in the 8.2 to 18 GHz band using two sets of waveguides. Shielding effectiveness from 30 to 90 dB were found for mono and three layer samples with a very light weight and good mechanical properties. [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]

The high-spin states of the two neutron-rich nuclei 88Kr52 and 89Rb52 have been studied from the 18O+208Pb fusion-fission reaction. Their level schemes were built from triple β-ray coincidence data, and β-β angular correlations were analyzed in order to assign spin and parity values to most of the observed states. The two level schemes evolve from collective structures to single-particle excitations as a function of the excitation energy. Comparison with results of shell-model calculations gives the specific proton and neutron configurations which are involved to generate the angular momentum alongthe yrast lines. [ABSTRACT FROM AUTHOR]

Odd-odd 136Cs nuclei have been produced in the 18O + 208Pb and 12C + 238U fusion-fission reactions and their γ rays studied with the Euroball array. The high-spin level scheme was built up to ~4.7 MeV excitation energy and spin I ~ 16h from the triple γ-ray coincidence data. The configurations of the three structures observed above ~2 MeV excitation energy are first discussed bγ analogy with the proton excitations identified in the semimagic 137Cs82 nucleus, which involve the three high-j orbits lying above the Z = 50 gap, πg7/2, πd5/2, and πhn1/2- This is confirmed by the results of shell-model calculations performed in this work. [ABSTRACT FROM AUTHOR]

Five N = 82 isotones have been produced in two fusion-fission reactions and their &ggr; rays studied with the Euroball array. The high-spin states of 139La have been identified, while the high-spin yrast and near-to-yrast structures of the four others have been greatly extended. From angular correlation analysis, spin values have been assigned to some states of 136Xe and 137Cs. Several cascades involving &ggr; rays of 139La have been found to be delayed; they deexcite an isomeric state with T1/2 = 315(35) ns located at 1800 keV excitation energy. The excited states of these five N = 82 isotones are expected to be due to various proton excitations involving the three high-j subshells located above the Z = 50 shell closure. This is confirmed by the results of shell-model calculations performed in this work. In addition, high-spin states corresponding to the excitation of the neutron core have been unambiguously identified in 136Xe, 137Cs, and 138Ba. [ABSTRACT FROM AUTHOR]

The 119_126Sn nuclei have been produced as fission fragments in two reactions induced by heavy ions: 12C + 238U at a bombarding energy of 90 MeV and 18O + 208Pb at 85 MeV. Their level schemes have been built from γ rays detected using the Euroball array. High-spin states located above the long-lived isomeric states of the evenand odd-A 120-126Sn nuclei have been identified. Moreover, isomeric states lying around 4.5 MeV have been established in 120,122,124,126Sn from delayed coincidences between the fission fragment detector SAPhIR and the Euroball array. The states located above 3 MeV excitation energy are ascribed to several broken pairs of neutrons occupying the vh11/2 orbit. The maximum value of angular momentum available in such a high-j shell, i.e., for midoccupation and the breaking of the three neutron pairs, has been identified. This process is observed for the first time in spherical nuclei. [ABSTRACT FROM AUTHOR]

Abstract: Thin (1–40μm) films of nanostructured polyaniline (PANI)-based composites are suggested for ppb range ammonia sensing. Three types of the composites have been studied: two core–shell systems with a poly(butyl acrylate) (PBuA) or poly(vinylidene fluoride) (PVDF) core and a PANI shell, and a composite based on PANI nanofibers embedded in a polyurethane (PU) matrix. Nanofibers and core–shell nanoparticles had a diameter around 100–200nm. The gas sensing ability of the nanostructured films was compared to ammonia concentrations from 20ppb to 10ppm through the change of the sensors resistance. All the composites showed high performances in terms of response time, reversibility and detection limit. Specifically, the last parameter was below 100ppb for films formed of the core–shell nanoparticles and below 20ppb for the nanofiber based composites. However, while the response times were similar for all of the samples, the films made of the contacting core–shell nanoparticles had a higher sensitivity than PANI nanofibers embedded in the PU film matrix. The obtained results showed that nanostructured PANI-based composites of different morphologies can be used as ultra-sensitive and low cost ammonia gas sensors. [Copyright &y& Elsevier]

The 83, 81As nuclei have been produced as fission fragments in the fusion reaction 18O + 208Pb at 85 MeV bombarding energy and studied with the Euroball array. Medium-spin states of 83, 81As have been established up to ~3.5 MeV excitation energy. From angular correlation analysis, spin values have been assigned to most of the 81As excited states. The behaviors of the yrast structures identified in this work are discussed in comparison with the general features known in the mass région. Then they are compared to the results of two theoretical approaches: the "rotor + quasiparticle" for 81As and the shell model using the effective interactions JUN45 for 83, 81Ks. [ABSTRACT FROM AUTHOR]

Cross-sections of the main reaction channels for the collision Ne + Pb at 7.9MeV/u were studied using the radioactive ion beam delivered by the SPIRAL facility and the VAMOS-EXOGAM experimental set-up. Angular distributions for the elastic and inelastic channels were extracted, together with distributions for the +1 n and -1 p channels. A comprehensive description of the present data is made within the GRAZING model approach. [ABSTRACT FROM AUTHOR]

Abstract: One of the first fusion–evaporation experiments using radioactive ion beams was performed at GANIL in order to study proton-rich nuclei of the light rare-earth region. The low production cross-section of the exotic species of interest, in combination with the low intensity of the beam and its induced background, demanded the use of a highly efficient experimental setup. This consisted of the EXOGAM -ray spectrometer coupled for the first time with both the DIAMANT charged-particle array and the VAMOS recoil spectrometer. In this report the experimental challenges of such studies will be discussed and the experimental achievements of the in-beam spectroscopy of proton drip-line nuclei using EXOGAM will be presented. [Copyright &y& Elsevier]

The odd-odd 88 37Rb51 and 86 35Br51 nuclei have been produced as fission fragments in the fusion reaction 18O$ + $208Pb at 85MeV bombarding energy and studied with the Euroball IV array. Their high-spin level schemes have been built from the triple $ \gamma$ -ray coincidence data and $ \gamma$ - $ \gamma$ angular correlations have been analyzed in order to assign spin and parity values to many observed states. The proposed configurations involve proton excitations from three sub-shells located close to the Fermi levels, $ \pi$ p3/2 , $ \pi$ f5/2 , and $ \pi$ g9/2 , the $ \nu$ d5/2 neutron acting as a spectator. The residual $ \pi$ $ \nu$ interactions are extracted from the multiplets of states resulting from the $ \pi$ p3/2 $ \nu$ d5/2 and $ \pi$ f5/2 $ \nu$ d5/2 configurations. The empirical values of the latter are discussed and compared to those known in two similar configurations having jp = jn with lp = ln + 1 , where the role of the tensor force had been highlighted. [ABSTRACT FROM AUTHOR]

The 81, 82, 83, 85Se nuclei have been produced as fission fragments in the fusion reaction 18O + 208Pb at 85MeV bombarding energy and studied with the Euroball IV array. Their high-spin level schemes have been built from the triple $ \gamma$ -ray coincidence data and $ \gamma$ - $ \gamma$ angular correlations have been analyzed in order to assign spin and parity values to many observed states. The lowest-spin states of the two-neutron and three-neutron configurations are strongly mixed with two-proton excitations among the fp orbits. On the other hand, the highest-spin states of these neutron configurations are found to remain almost pure. Neutron excitation across the N = 50 gap is observed both in 83Se49 and in 85Se51 . [ABSTRACT FROM AUTHOR]

Theoretical predictions suggest the presence of tetrahedral symmetry as an explanation for the vanishing intra-band E2 transitions at the bottom of the odd-spin negative-parity band in 156Gd. The present study reports on experiment performed to address this phenomenon. It allowed to remove certain ambiguouities related to the intra-band E2 transitions in the negative-parity bands, to determine the new inter-band transitions and reduced probability ratios B(E2)/B(E1) and, for the first time, to determine the experimental uncertainties related to the latter observable. [ABSTRACT FROM AUTHOR]

High-spin states in the 142Ce and 140Ba nuclei have been populated in the 12C + 238U and 18O + 208Pb fusion-fission reactions at 90MeV and 85MeV bombarding energy, respectively. The emitted γ -radiation was detected using the Euroball III and IV arrays. The high-spin yrast and near-to-yrast structures of 142Ce have been considerably extended. The level scheme of 140Ba has been extended by six new levels. The newly observed structures in these N = 84 isotones are discussed by analogy with the neighbouring nuclei. [ABSTRACT FROM AUTHOR]

Independent fission fragment yields have been obtained for the six fragment pairs ( Z L/ Z H = 44/46 , 42/48, 40/50, 38/52, 36/54 and 34/56) in 208Pb(18O, f ) at the beam energy E = 85 MeV. γ -ray spectroscopy technique was applied to analyze the experimental data. With use of these data the mass distribution of fission fragments was restored. Data on average fragment spin distribution and total neutron multiplicity are presented. The agreement of the obtained results with other experimental data proves the validity of the applied method to solve this kind of problems. [ABSTRACT FROM AUTHOR]

The 84, 85Br nuclei have been produced as fission fragments in the fusion reaction 18O + 208Pb at 85MeV bombarding energy and studied with the Euroball IV array. The high-spin states of the odd-odd 84Br nucleus have been identified for the first time, the observed structure being built on the known 6- isomeric state. High-spin states of 85Br have been observed up to 5.4MeV excitation energy and spin I ∼ 21/2. From angular correlation analysis, spin values have been assigned to most of the 85Br excited states up to 4MeV. None of these excited states has been found to exhibit a delayed decay having T 1/2 > 10ns. All the observed states in 84, 85Br can be described by various proton excitations involving at least the two sub-shells ( π f 5/2 and π p 3/2) located just above the Z = 28 shell closure. [ABSTRACT FROM AUTHOR]

The 87Kr nucleus has been produced as fission fragment in the fusion reaction 18O + 208Pb at 85MeV bombarding energy and studied with the Euroball IV array. High-spin states of this neutron-rich isotope have been identified for the first time. Its level scheme has been obtained up to 6.3MeV excitation energy and spin I ∼ 23/2ℏ. Its structure is interpreted by analogy with those of the heavier isotones. The proposed configurations involve both proton and neutron excitations from several sub-shells located close to the Fermi levels, particularly ν d 5/2, π p 3/2 f 5/2 and π g 9/2. Moreover, a revised spin value of 5/2- for the 87Br ground state is proposed. [ABSTRACT FROM AUTHOR]

High-spin states of the N = 87 nuclei, 147Nd and 145Ce, have been populated in the 12C + 238U and 18O + 208Pb fusion-fission reactions at 90 MeV and 85 MeV bombarding energy, respectively. The emitted γ-radiation was detected using the Euroball III and IV arrays. High-spin states of the 147Nd isotope have been identified for the first time. The high-spin yrast and near-to-yrast structures of the 145Ce nucleus have been considerably extended. The newly observed structures, discussed by analogy with the neighbouring isotones, show the coupling of an h 9/2 neutron to the quadrupole and octupole excitations of the core. [ABSTRACT FROM AUTHOR]

The84Se nucleus has been produced as fission fragment in the fusion reaction18O +208Pb at 85MeV bombarding energy and studied with the Euroball IV array. Medium-spin states of this neutron-rich isotope have been identified for the first time. Its level scheme has been obtained up to 4.9MeV excitation energy and spinI~ 7?. Its structure is interpreted by analogy with those of the stable heavier isotones. The evolution of the energy of theN= 50 neutron-core excitation is discussed as a function of the proton number. [ABSTRACT FROM AUTHOR]

High-spin states from the three-quasiparticle (3qp) configuration &paig9/2vh211/2 in the neutronrich 49In isotopes have been studied in the framework of shell model calculation. The two-body residual interactions needed for such calculations have been extracted from the level schemes of neighbouring nuclei. In particular, the evolution of the proton-neutron &paig9/2vh211/2 interaction has been analyzed as a function of the neutron number. When the gradual filling of the vh211/2 sub-shell is taken into account, the results of the 3qp configuration calculations are found to be very close to the experimental positive-parity yrast states located above 2 MeV excitation energy in 113-121In. Moreover, several long-lived isomeric states with positive parity are predicted in 123, 125, 127In. [ABSTRACT FROM AUTHOR]

An experiment has been performed to investigate the structure at high spin of the neutron-deficient polonium isotopes using the Recoil Filter Detector coupled to the EUROBALL IV gamma array. High spin states of [sup 200,201]Po have been populated by the [sup 30]Si+[sup 176]Yb reaction at a beam energy of 160 MeV. We report here the performances of the RFD + EUROBALL IV coupling. [ABSTRACT FROM AUTHOR]

High-spin states in 108,110Pd isotopes are studied by γ-ray spectroscopy of heavy-ion-induced fission. The Pd isotopes are produced in the fission channel of the 31P + 176Yb reaction at beam energy 152 MeV. The prompt γ-rays are detected with the EUROBALL4 multidetector array. The yrast states of 108,110Pd have been observed above the region of the first backbend. The level scheme of 108Pd was extended with a new negative-parity band. The yrast sequence in 110Pd is observed up to spin I = 14+ and negative-parity bands have also been identified. The back bending in these even-mass Pd isotopes is associated with the alignment of the neutron (h11/2)² pair. The negative-parity states arise from two neutron configurations vh11/2 ⊗ vg7/2 and vh11/2 ⊗ vd5/2 and they are interpreted in the frame of two-quasiparticle + rotor model as semidecoupled bands. The observed experimental staggering in the γ-bands of 108,110Pd supports the theoretical predictions for γ-instability of their shapes. [ABSTRACT FROM AUTHOR]

The 110,112 Rh and 114',16Ag nuclei have been produced as fission fragments in the fusion reaction 18 + 208Pb at 85 MeV. Their level schemes have been built from gamma-rays detected using the Euroball IV array. High-spin states of these neutron-rich nuclei have been identified for the first time. The yrast structures consist of rotational bands in which the odd proton occupies the πg9/2 sub-shell and the odd neutron the vh11/2 sub-shell. The evolution of the πg9/2 ® vh11/2 band structure is analyzed as a function of the neutron number. [ABSTRACT FROM AUTHOR]