Search results for "raman microscopy"
showing 6 items of 6 documents
Decorated pottery study: Analysis of pigments by x-ray absorbance spectroscopy measurements
2007
Characterization of pigments on decorated pottery fragments has been fully carried out by nondestructive x-ray absorbance spectroscopy (XAS). The samples were a series of pottery shards excavated from the archeological site of Caltagirone (Sicily, Italy), a well-known ceramic production center. Aesthetical criteria and morphological observations allowed us to attribute the samples to quite different historical periods, starting from the 18th century B.C. up to the 16th century A.D. An extensive time interval led us to suppose that different materials and techniques were used for the production of the ceramic paste and also for the preparation of pigments. XAS measurements were performed at …
Spectroscopic analysis used to uncover the original paint colour of the Helsinki Government Palace tower clock faces
2016
The paint stratigraphy of the two clock faces from the tower clock of the Government Palace in Helsinki (Finland) was analysed in order to determine their original colour before restoration works. Paint cross-section samples from both clock faces were analysed by confocal Raman microscopy and scanning electron microscopy coupled to an energy dispersive X-ray spectrometer (SEM-EDS). The results revealed the complex superimposition of paint layers applied over the original black colour. FTIR/ATR analyses proved that the original paint was prepared with linseed oil-resin media. Most likely not all of the different layer colours were visible. Some of the layers were likely to have been a primer…
Measure of a limestone weathering degree using Laser Scanner.
2013
The weathering degree of the building materials and natural stones is generally quantified as the decrement of some mechanical features that can be measured experimentally by means of compressive tests or point load tests in the laboratory or Schmidt hammer tests carried out in situ. Such destructive or damaging tests are unacceptable in case of cultural heritage since even small amounts of damage must be avoided. This work shows a correlation between Schmidt hammer rebound values and the reflectivity that is detected by means of terrestrial scanner laser; therefore it allows assessing the weathering degree of buildings or stones in situ. The results demonstrate that such an investigation c…
Two-component self-assembly with solvent leading to "wet" and microcrystalline organogel fibers
2014
Abstract Hypothesis The microcrystalline fibers of N -(2-aminoethyl)-3α-hydroxy-5β-cholan-24-amide 1 provided a useful model system for studying the complex relationship between morphology, experimental parameters, solvent, and the phenomenon of organogelation. The presence of solvents in the solid forms of 1 along with crystallization behavior suggested solvate formation and polymorphic behavior. Experiments Forty solid state- and xerogel samples of 1 formed in organic solvents and in three categories of experimental conditions were analyzed with single crystal X-ray diffraction (XRD), powder X-ray diffraction (PXRD), Raman microscopy, and attenuated total reflection Fourier-transform infr…
Mortars and Plasters under the Mosaics and the Wall Paintings of the Roman Villa at Piazza Armerina, Sicily
2010
The Roman Villa at Piazza Armerina in Sicily, built in many successive steps over the 2nd and 3rd centuries A.D., is renowned all over the world for both the wealth and the refinement of its mosaic floors. In February 2007 the Regional Government of Sicily started a restoration project of the whole archaeological site. The systematic survey and study of all decorative elements highlighted the value of wall paintings, which until then were almost unknown except for casual approaches to specific problems of conservation, carried on without any relation to the far and away famous mosaics. This paper shows the results of a physical chemical investigation of the mortars used for both floors and …
Structural studies of dielectric polymer nanocomposites
2013
A constant need for the development of new and superior materials is always present; for example, a better electrical insulator would enable more efficient use of electrical power. Polymeric nanocomposites, i.e. nanodielectrics, are thought to have unique electrical properties. The basic chemical constitution of a material alone fails to provide an understanding of how desired properties of a material originate or predict the long term behavior of a material. We need to define the structure behind the functionality of a material. To do that, the structure of the material must be studied on several scales. This research was part of the Finnish Funding Agency for Technology and Innovation (TE…