Structural investigation of the high pressure intrusion/extrusion of different electrolyte aqueous solutions (NaCl, NaBr and CaCl2) with different concentrations (2M and 3M) in a pure-silica chabazite was carried out. In situ synchrotron X-ray powder diffraction experiments were performed in the pressure range of 0.12 -2.6 GPa and upon pressure release, in order to unravel the interactions among intruded species and host material. The energetic performance of the systems were determined by porosimetric studies. Results show that cation in the salt seems to influence the intrusion-extrusion pressures, whereas the structural evolutions, undergone by the systems upon pressure-induced intrusion, are essentially independent on the nature of the penetrating media.Moreover, the initial electrolyte concentration seems to influence only the value of the intrusion pressure, but neither the amount nor the interaction mode of the intruded species. Both water and salt molecules enter the pores and the penetration of comparable extra-framework volumes occurs at similar pressure values. However, the composition of intruded species is different from that of initial solution and depends on applied pressure that reinforces the hypothesis on ion desolvation under penetration into the pores. After pressure release, pure-silica chabazite intruded by NaCl and NaBr aqueous solutions does not recover the initial cell volume and partially retains the intruded extra-framework species. On the contrary, the zeosil intruded by CaCl2 recovers the original cell parameters. These differences have been structurally interpreted on the basis of the electrolyte/zeolite interactions. Interestingly, the extrusion behavior results to be mainly determined by the interactions of the anion with silanol defects of chabazite framework, rather than by the coordination bonds of the cation with the framework oxygen atoms.

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The intrusion–extrusion process of various electrolyte aqueous solutions in a hydrophobic pure-silica LTA zeolite was investigated for energetic purposes by means of in situ HP XRPD, porosimeter tests, thermogravimetric analysis and NMR spectroscopy.

An overview of all the studies on high-pressure intrusion—extrusion of LiCl aqueous solutions in hydrophobic pure silica zeolites (zeosils) for absorption and storage of mechanical energy is presented. Operational principles of heterogeneous lyophobic systems and their possible applications in the domains of mechanical energy storage, absorption, and generation are described. The intrusion of LiCl aqueous solutions instead of water allows to considerably increase energetic performance of zeosil-based systems by a strong rise of intrusion pressure. The intrusion pressure increases with the salt concentration and depends considerably on zeosil framework. In the case of channel-type zeosils, it rises with the decrease of pore opening diameter, whereas for cage-type ones, no clear trend is observed. A relative increase of intrusion pressure in comparison with water is particularly strong for the zeosils with narrow pore openings. The use of highly concentrated LiCl aqueous solutions instead of water can lead to a change of system behavior. This effect seems to be related to a lower formation of silanol defects under intrusion of solvated ions and a weaker interaction of the ions with silanol groups of zeosil framework. The influence of zeosil nanostructure on LiCl aqueous solutions intrusion–extrusion is also discussed.

In this work, nanosized RHO zeolite samples with different Si/Al ratios were synthetized and tested for CO2 adsorption by combining in situ IR spectroscopy and in situ X-ray powder diffraction using synchrotron radiation. The structural changes of the RHO nanosized zeolites subjected to high temperature treatment (350 ºC) and CO2 adsorption (1 and 5 Bars) studied by high-resolution X ray powder diffraction indicated the presence of two phases with different cell parameters in both samples. The combination of the X-ray technique with IR allowed evaluation of the CO2 adsorption capacity of the samples and their adsorption dynamic. The results indicated that the CO2 adsorption capacity is mainly related to the sodium content in the nanosized RHO crystals. The adsorption experiments performed showed that 1 bar CO2 is sufficient to saturate the RHO samples at room temperature, and no change in the CO2 adsorption capacity at 5 bars was observed.

Following Phase 2 of the upgrade of the ESRF in which the storage ring was replaced by a new low-emittance ring along with many other facility upgrades, the status of ID22, the high-resolution powder-diffraction beamline, is described. The beamline has an in-vacuum undulator as source providing X-rays in the range 6–75 keV. ID22's principle characteristics include very high angular resolution as a result of the highly collimated and monochromatic beam, coupled with a 13-channel Si 111 multi-analyser stage between the sample and a Dectris Eiger2 X 2M-W CdTe pixel detector. The detector's axial resolution allows recorded 2θ values to be automatically corrected for the effects of axial divergence, resulting in narrower and more-symmetric peaks compared with the previous fixed-axial-slit arrangement. The axial acceptance can also be increased with increasing diffraction angle, thus simultaneously improving the statistical quality of high-angle data. A complementary Perkin Elmer XRD1611 medical-imaging detector is available for faster, lower-resolution data, often used at photon energies of 60–70 keV for pair-distribution function analysis, although this is also possible in high-resolution mode by scanning up to 120° 2θ at 35 keV. There are various sample environments, allowing sample temperatures from 4 K to 1600°C, a capillary cell for non-corrosive gas atmospheres in the range 0–100 bar, and a sample-changing robot that can accommodate 75 capillary samples compatible with the temperature range 80 K to 950°C.

The species of the brachiopod Gigantoproductus are giants within the Palaeozoic sedentary benthos. This presents a dilemma as living brachiopods have low‐energy lifestyles. Although brachiopod metabolic rates were probably higher during the Palaeozoic than today, the massive size reached by species of Gigantoproductus is nevertheless unusual. By examining the diet of Gigantoproductus species from the Visean (Mississippian, Carboniferous) of Derbyshire (UK), we seek to understand the mechanisms that enabled those low‐metabolism brachiopod species to become giants. Were they suspension feeders, similar to all other brachiopods, or did endosymbiosis provide a lifestyle that allowed them to have higher metabolic rates and become giants? We suggest that the answer to this conundrum may be solved by the identification of the biogeochemical signatures of symbionts, through combined analyses of the carbon and nitrogen‐isotopic compositions of the occluded organic matrix within their calcite shells. The shells are formed of substructured columnar units that are remarkably long and a few hundreds of microns wide, deemed to be mostly pristine based on multiple analyses (petrography, cathodoluminescence (CL), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM)); they contain occluded organic fractions detected by TEM, nuclear magnetic resonance (NMR) and gas chromatography mass spectrometry (GC‐MS) analyses. We conclude that the gigantic size reached by the species of Gigantoproductus is probably the result of a mixotroph lifestyle, by which they could rely on the energy and nutrients derived both from photosymbiotic microbes and from filtered particulate food.