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This study presents the results of an archaeometrical investigation performed on 75 black glass beads dated to the 9th-5th century BC coming from Bologna, Cumae and Pozzuoli (Italy), and Chotin (Slovakia). The analyses of the major, minor and trace elements -as well as that of Sr and Nd isotopes performed on a selection of samples coming from Bologna -provided evidence for two different production technologies in Iron Age black glass found in Italy (natron glass, probably produced in Egypt) and Slovakia (wood ash glass, probably produced in Europe). In both cases, the glasses derive their black colouration from the high presence of iron (around 12% FeO), introduced into the glass batches through the intentional choice of dark sands. The production model appears to be small-scale and experimental, characterised by the use of non-sorted raw materials and poorly defined formulae, producing glass with a high chemical variability. The wood ash technology appears to have dropped out of use in Europe until the Medieval period, while natron production spread quickly, becoming predominant throughout the Mediterranean. Response to Reviewers:Answers to referees' comments and list of revisionsReviewer #1: The authors took in consideration most of the comments raised by this reviewer. Few points remain to be clarified.-The experimental section has been improved. The authors added a comment regarding the experimental protocol used for EPMA being equal to the condition reported in Henderson 1988b. However, the LA-ICPMS section becomes more unclear than before. In the original version we read that NIST 612 and 614 were used for external calibration, and that two glass standards (not specified) were used as secondary standards to check for accuracy and precision. The new version states instead that NIST 610 and 614 were used for external calibration, and NIST 612 was used as secondary standard to check for accuracy and precision. What happened to

A tough challenge in nanomaterials chemistry is the determination of the structure of multicomponent nanosystems. Dye-zeolite L composites are building blocks of hierarchically organized multifunctional materials for technological applications. Supramolecular organization inside zeolite L nanochannels, which governs electronic properties, is barely understood. This is especially true for confined close-packed dye molecules, a regime not investigated in applications yet and that might have great potential for future development in this field. Here we realize for the first time composites of zeolite L with maximally-packed fluorenone molecules and elucidate their structure by integrated multi-technique analyses. By IR, thermogravimetric and X-ray diffraction we establish the maximum degree of dye loading obtained (1.5 molecules per unit cell) and by modeling we reveal that at these conditions fluorenone molecules form quasi 1-D supramolecular nanoladders running along the zeolite channels. Spatial and morphological control provided by the nanoporous matrix combined with a complex blend of strong dye-zeolite and weaker dye-dye van der Walls interactions lie at the origin of this unique architecture, which is also stabilized by the hydrogen bond network of co-adsorbed water molecules surrounding the dye nanoladder and penetrating between its rungs.

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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