Papiers, articles, revues, thèses et hdr soutenues… retrouver les dernières publications de nos chercheurs
Vous pouvez consultez l’ensemble des publications scientifiques du MONARIS sur le portail HAL-Sorbonne Université
"Miletus Ware", considered as one of the first wares produced by Ottoman potters in western Anatolia, featured new typological and stylistic characteristics that suggested the introduction of new recipes and the use of new materials in the local repertoire. This study, conducted on archaeological samples of Miletus Ware from eight sites in Turkey and in the Crimea, supports this view. It focuses on the decoration techniques, through the analyses of glazes and underglaze decorations using SEM-EDS and Raman spectroscopy. The results show that, compared to what Byzantine and Beylik potters previously produced in western Anatolia, there were two main innovations in the Miletus Ware glaze production technology. First, its glaze recipe included new sodium-based fluxes. Second, some underglaze decorations as represented by the black and dark-blue-colored ones - obtained respectively through the use of pigments featuring magnesiochromite and cobalt - were produced with materials that had not been used in the region before.
Gold electrodes were modified by silver and gold nanocrystals (NCs) that self-organize onto the surface. Their optical properties were explored by measuring electro-reflectance spectra as a function of electrode potential. Below their oxidation potential, no shift of the reflectance maximum was observed for Ag NCs. This can be explained by a low interfacial capacitance resulting from the impossibility for the electrolyte to penetrate into the hydrophobic layer created by the NCs dodecanethiol ligands. Conversely, a non-monotonous evolution was observed with the electrode potential for oleylamine capped Au NCs.
We performed the systematic measurements of line intensities of ro-vibrational absorption transitions of the nu(3) and 2 nu(3)-nu(3) parallel bands of (CH3Cl)-C-12-Cl-35 and (CH3Cl)-C-12-Cl-37 isotopes. The spectra were recorded in the spectral region between 650 and 800 cm(-1) with a high-resolution Fourier transform spectrometer. A mono-spectrum fitting technique was used to fit a series of seven spectra at pressures of CH3Cl ranging from 1.02 to 10.24 mbar to retrieve line intensities of 2385 transitions of the two isotopic species. The measured line intensities are discussed in relation to rotational quantum numbers, and used to derive the square of the transition dipole moments for each line. The analysis of these moments allows us to derive a consistent set of line intensity parameters, such as vibrational transition moments, band intensities as well as Herman-Wallis coefficients for both bands...
Cultural heritage often brings to mind elements like sculptures, paintings, monuments, and buildings as well as archeological objects. Today, underwater heritage and its surrounding environment are also considered part of cultural heritage because communities identify themselves with the natural landscape. This study is focused on a shipwreck belonging to the second half of the 15th century that was discovered in 1998 by chance in the sediments of the Urdaibai estuary, in Urbieta (Gernika, Basque Country), at 4 m underground. A scientific study presented in this work was performed, as this archeological site was absolutely out of context and in need of a preservation and conservation procedure. Therefore, our aim was to shed light on the origin of the shipwreck and to assess the conservation state to develop a precise conservation plan. Pursuing this objective, a first analysis on three selected groups of iron nails was performed, looking at the raw materials and degradation patterns through the knowledge of the alteration compounds. By means of nondestructive analytical techniques such as Raman spectroscopy and X‐ray fluorescence, the presence of iron, zinc, and silicon was detected in the outer layer of the iron samples. The analysis of the nails and wood of the shipwreck confirmed that the presence of zinc in the pieces indicates an important impact of the contaminated sediments deposited in the last 80 years on the upper part of the burial in which the shipwreck was located.
Asbestos-containing pottery shards collected in the northeast of Corsica (Cap Corse) and dating from the 19th century, or earlier, have been analyzed by SEM-EDS, XRPD, FTIR and Raman micro-spectroscopy. Blue (crocidolite) and white (chrysotile) asbestos fiber bundles are observed in cross-sections. Most of the asbestos is partly or totally dehydroxylated, and some transformation to forsterite is observed to occur, indicative of a firing above 800 degrees C. Examination of freshly fractured pieces shows a nonbrittle fracture with fiber pull-out, consistent with a composite material behavior, which makes these ceramics the oldest fiber-reinforced ceramic matrix composite. Residues indicate the use of this pottery as a crucible for gold extraction using cyanide.
Twelve rare watches with painted enamels, mostly produced in France, from the 17th and 18th centuries in the collections of Musée du Louvre in Paris were analysed on-site in order to characterize the materials used in their enamels and the enamelling technique. All the watches were analysed by mobile Raman microspectroscopy and five of them were also analysed by pXRF. Pigments (Naples Yellow pyrochlore, hematite, carbon, lapis lazuli, arsenic sulphide, manganese oxides), opacifiers (cassiterite, lead arsenates) and corresponding lead-rich glassy silicate matrices were identified by one or two methods. Similar to the oil painting or tempera techniques, different hues of the related enamels were obtained by mixing many colouring agents, rather than using ‘pure’ enamels as in the case of Limoges enamelled objects. Lead arsenate apatite detected in some of the 17th century blue enamels is related to the use of European arsenic-rich cobalt ores, as also characterized in the blue (soft-paste) porcelain decors and high-quality Limoges enamels. The presence of colloidal gold (Au° nanoparticles) was indirectly detected by the Raman technique in the 18th century watches and confirmed by pXRF. At least three types of Naples Yellow pigment were identified with Sb-rich, Sn-rich and mixed Sb-Sn-Fe-Zn compositions.
For the first time the nu(4) NH2 scissors band has been assigned in a high-resolution infrared spectrum. A rotationally resolved spectrum of methylamine was recorded using two infrared spectroscopic techniques. A White-type multi-pass cell device coupled to the Bruker IFS 125 HR Fourier transform spectrometer was implemented on the AILES beamline at the SOLEIL synchrotron facility and a room-temperature spectrum of the whole band in the region of 1540-1710 cm(-1) was recorded with a resolution of 0.001 cm(-1). Then, a low-temperature high-resolution spectrum in the 1622.5-1655.6 cm(-1) range of Q and R branches of the nu(4) band was recorded using a quantum cascade laser spectrometer. Preliminary assignment was carried out in the NH2 scissors band region, and about 2200 transitions for K from 0 to 6 have been assigned for A, B, and E-1 symmetry species. The simultaneous fit of assigned lines using a group-theoretical effective Hamiltonian was not successful; instead simple polynomial series expansions were used for each symmetry and K value.
A new spectroscopic setup dedicated to the optical study of materials in the sub-Kelvin temperature range, available on the AILES beamline of synchrotron SOLEIL is described. This ensemble, based on an adiabatic demagnetization refrigerator, has been designed for spectroscopy in the far-infrared and terahertz domains. The combination of the cryogenic set-up with synchrotron radiation allows for reflectivity and transmission measurements down to 95 mK and 144 mK, respectively, with reproducibility better than 0.5%.