Search results for "Micro raman"
showing 7 items of 7 documents
Splitting of surface-related phonons in Raman spectra of self-assembled GaN nanowires
2012
cited By 2; International audience; Micro Raman spectroscopy studies have been performed on GaN nanowires grown by Plasma-Assisted Molecular Beam Epitaxy on Silicon (111) substrate. From the analysis of experimental data, the emergence of a two peaks band located near 700 cm-1 has been attributed to the Raman scattering by surface-related phonons. We have analyzed the surface character of these two modes by changing the dielectric constant of the exterior medium and some experimental parameters. Furthermore, a theoretical model describing the nanowires ensemble by means of an effective dielectric function has been used to interpret the Raman scattering results. Those numerical simulations a…
Application of micro Raman spectroscopy to industrial FC membranes
2007
Raman spectra of as-received and protonated membranes (Nafion® NRE-212, Fumapem® F-14100 and Fumasep® FAA) were measured with He-Cd and Ar laser. For the first time the Raman and IR spectra are reported of Fumasep membranes. Most of peaks in vibration spectra active in Raman and IR of membranes are interpreted with C-F, C-S, C-O-C, SO3, C-C bonds. The vibration region connected with protons and H-O bond in both types of membranes is found in Raman and IR spectra.
XRD and micro Raman characterization of epitaxial Bi-2201, Bi-2212 and Bi-2223 thin films
1997
Copyright (c) 1997 Elsevier Science B.V. All rights reserved. Micro Raman characterization is performed on high quality thin films of Bi 2 Sr 2 CuO 6+x (2201), Bi 2 Sr 2 CaCu 2 O 8+x (2212), Bi 2 Sr 2 Ca 2 Cu 3 O 10+x (2223) made by dc-sputtering. Single crystal X-ray measurements reveal the full epitaxy of the films, which allows for polarized Raman spectra to be obtained.
Le indagini scientifiche per lo studio e la conservazione dei beni culturali : un approccio analitico integrato, la conoscenza dei materiali costitut…
2019
The icon Virgin Hodegetria, now in Santa Maria Nuova Cathedral in Monreale near Palermo (Italy), probably dates from the beginning of thirteen century could be considered one of the earliest examples of medieval icon in Sicily. The icon is distinguished from other southern icons by the strong Byzantine matrix and by its size (169x131x3 cm). Since 2015, the icon is part of the Arab-Norman Palermo UNESCO Heritage. This paper will deal with historical and scientific investigations on the icon to better understand the painting materials, the executive technique and to resolve question about on-going restoration in planning a complex conservation project. Examination of the icon was both non-inv…
The Painted Silk Panels of Palazzo Barberini at Rome. The Scientific Investigation and Preservation Challenge
2013
Abstract This paper reports the study carried out on the 18th century painted silk panels that cover the walls of the so called Salotto delle sete dipinte in Palazzo Barberini at Rome on the occasion of the conservation work started in 2007. Microscope and spectroscopy investigations were performed in order to study the materials and the realization techniques of the painted silk panels and to evaluate the conservation conditions. Moreover ageing tests were performed in order to evaluate the stability of the consolidant/protective product used for the silk panels.
Micro-Raman study of red decorations in French faiences of the 18th and 19th centuries
2006
Obtaining the red color was a technical and economic challenge for the French faience manufactories in the 18th and 19th centuries. The tendency of the red hematite to turn into drab brown during the firing process explains the difficulty in obtaining this color. Red decorations in shards coming from the four production centers of faience manufacturing during this period—Rouen (northwest), Nevers (central), Thiviers (southwest) and Argonne (northeast)—have been studied by means of micro-Raman spectroscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Among them, Thiviers appears to be the leader thanks to a particular reddish sandstone called ‘Gres de T…
Archaeometric Characterisation of Decorated Pottery from the Archaeological Site of Villa dei Quintili (Rome, Italy): Preliminary Study
2019
This work focused on the study of decorated pottery dated back to the 16th century from the Roman archaeological site of Villa dei Quintili, a monumental complex located in the south-eastern part of Rome (Italy). A minero-petrographic and geochemical study was undertaken to analyse five archaeological samples in order to define textural features and raw materials used for their production, along with the chemical and physical composition of the superficial decorative glazed coatings. For this purpose, different analytical methods were used, such as polarising optical microscope (POM), X-ray diffraction (XRD), micro-Raman spectroscopy, X-Ray fluorescence (XRF), and electron microprobe analys…