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In a recent manuscript, the discovery of a new phenomenon in glasses has been reported: {\it glass paramagnetism}, that is the intrinsic magnetisation developed by a substance that has failed to crystallise in a temperature quench when placed in an external magnetic field. The field- ($H$) and especially the temperature- ($T$) dependence of the intrinsic magnetisation $M_{intr}=M_{intr}(H,T)$ is very unexpected, with broad peaks developing for high $H/T$ and marked $T$- oscillations at fixed $H$ for intermediate-to-high temperatures. In this work we present details on the samples, new data for other glassy systems and especially the theoretical background that is capable of explaining most of the experimental data. New phenomena are however emerging from these data, for example a deviation from the Curie-like behaviour of the magnetic susceptibility ($M_{intr}/H$ at low fields) due to the glassy structure alone as well as evidence for new and intriguing quantum coherence effects at the lowest temperatures., Comment: 29 pages, 24 figures, submitted for publication

International audience; In this study, the microstructure of mock-up mortar specimens for a historic environment, composed of different mixtures, was studied using mercury intrusion porosity (MIP) and microcomputed tomography (µCT), highlighting the advantages and drawbacks of both techniques. Porosity, sphericity, and pores size distribution were studied, evaluating changes according to mortar composition (aerial and hydraulic binders, quartz sand, and crushed limestone aggregate). The µCT results were rendered using 3D visualization software, which provides complementary information for the interpretation of the data obtained using 3D data-analysis software. Moreover, µCT contributes to the interpretation of MIP results of mortars. On the other hand, MIP showed significant ink-bottle effects in lime and cement mortars samples that should be taken into account when interpreting the results. Moreover, the MIP results highlighted how gypsum mortar samples display a porosity distribution that is best studied using this technique. This multi-analytical approach provides important insights into the interpretation of the porosimetric data obtained. This is crucial in the characterization of mortars and provides key information for the study of building materials and cultural heritage conservation.

Mg(Al)O supported Ru and Rh catalysts with low loading of active metal (0.5 wt.%) were tested in the steam reforming (SR) of acetic acid (AA) to hydrogen rich mixtures. Two synthetic procedures were adopted to deposit metal nanoparticles on support material: conventional impregnation from metal chlorides aqueous solutions and size-controlled metal nanoparticles (SCMNPs) deposition method. SCMNP derived Ru catalysts showed good performances fully comparable to standard Rh based systems. After 20 h t.o.s. at reaction temperature of 700 °C, steam-to-carbon ratio of 3 and weight hourly space velocity of 6 h −1 , Ru catalysts showed 100% conversion and hydrogen yield higher than 70%. The presence of well formed metal nanoparticles and the residual hydrotalcite present in the support play a determinant role in limiting the deactivation by coke deposition and by nanoparticles sintering.

The Canalone Porta fault, developed within dolomitic and marly limestones in the Grigna Massif (Southern Alps, Italy), shows two types of reddish veins: one parallel to the principal slip plane (fault-veins) and the other intruding the fault host rock (injection-veins). The veins have a dominant carbonate composition and show a microtexture with millimetre-sized clasts embedded in a fine-grained matrix. This matrix is composed of micrometre-sized globular clusters of micrometre- to nanometre-sized calcite and dolomite crystals, bound together by K-bearing aluminosilicate glass. Field and petrological data suggest that this carbonate-rich matrix represents an undercooled melt-bearing assemblage produced at T?700°C and P?0.1-0.2GPa. The Canalone Porta veins are therefore carbonate pseudotachylytes, i.e. the friction-induced melting product of carbonate rocks. Herein, we discuss the scarcity of these rocks in general and criteria to find and recognize them along relatively deep fault zones. © 2011 Blackwell Publishing Ltd.

Dinitrogen (N2) adsorption on overexchanged Cu-ZSM-5 (Si/Al ) 25, 104% ion exchange from copper acetate)was studied at 302 K by diffuse reflectance infrared spectroscopy (DRIFTS), N2-adsorption isotherms, and temperature-programmed N2 desorption (TPD). We found that Cu-ZSM-5 adsorbs N2 at least in two different modes. The weaker mode, evidenced by the appearance of an IR band at 2295 cm-1, was already reported in the literature and assigned to N2 coordinated on-top on Cu(I) sites. This kind of adsorption occurs only under N2 atmosphere and is completely reversible at 302 K. The stronger mode, revealed by TPD and by the difference between total and reversible N2-adsorption isotherms, is completely irreversible at 302 K. The band at 2130 cm-1, previously assigned by us to this kind of strong N2 adsorption, is not observed if ultrapure gases are utilized. The introduction of controlled amounts of impurities, together with the utilization of 15N2 and 13CO shows that this band is instead related to hydrated Cu(I)-CO species formed by accumulation on the sample of traces of H2O in the N2 flow and from residual CO produced during activation. The coordination of N2 onto Cu(I)...Cu(I) dimers is proposed as an adequate model to describe this IR-silent irreversible N2 adsorption.

Pd(acac)2 was supported on a highly dehydroxylated and decarbonated magnesium oxide surface (MgO500), on an untreated MgO surface (MgOAIR), and on a silica. EXAFS and DRIFT data indicate that the organopalladium complex is adsorbed intact on all the surfaces, but its dispersion is dependent on the nature of the surface. On MgO500, dispersion at the molecular level occurs, in contrast to the formation of islands of multilayers on MgOAIR and silica. The final properties of the metal phase, formed by H2 treatment at 500°C, are dependent on precursor-surface interactions. HRTEM analysis shows a narrow distribution of the metal particles centered at 0.6 nm on MgO500, and a wide diameter distribution around 6.1 and 9.9 nm on MgOAIR and SiO2 respectively. In the n-heptane dehydrocyclization at 500°C, the highest selectivity is shown by Pd/MgO500 catalysts and it is consistent with a predominant fraction of very small particles in close contact with surface basic sites.