SEM-EDS and XRF analyses of pellets produced with powdery clay and ceramic standards and fired at... more SEM-EDS and XRF analyses of pellets produced with powdery clay and ceramic standards and fired at increasing temperatures showed a systematic overestimation of the abundance of heavier detected elements (K, Ca, Ti and Fe) using the conventional procedure of calibration with massive mineral/glass certified materials followed by normalization of the detected values. Errors were particularly noticeable for samples fired in the typical range of temperatures of archaeological and historical pottery (600–900 °C) and for unfired samples, and were attributed to material porosity. An extremely simple method based on the SEM-BSE image analysis is proposed for the semi-quantitative evaluation of porosity. A remarkable increase of accuracy, especially for SEM-EDS, was evidenced when the calibration is performed using a standard with porosity comparable to the samples, with regard to the pottery temperature range. Conversely, for the analysis of high-fired samples simulating porcelain (1200 °C) no substantial difference was observed with respect to the usual massive minerals/glass calibration. Finally, results showed the unsuitability of calibration performed by means of unfired pellets, for both pottery and porcelains.
A multitechnique (SEM-EDX, XRD, TGA) characterization was performed on several materials and arte... more A multitechnique (SEM-EDX, XRD, TGA) characterization was performed on several materials and artefacts from Old Nisa excavated during the recent Italian–Turkmen archaeological expedition,which involved a large building in the SW corner of the citadel, formed by rooms utilized as warehouses and workshops. Polygenic conglomerates archaeologically classified as anhydrites were examined and proved to be highly compatible with all the studied architectural artefacts (a plaster, a mortar, and a mould), making strongly plausible their identification as raw materials. Besides, several pigments at different stages of the manufacturing process were examined. A very complex situation emerged, suggesting the existence of different productive processes. At last, a black cylindrical object, identified as a seal, but almost completely devoid of engravings, turned out to be made of graphite and obtained by turning. The results of the analyses on these materials shed a newlight on the complexity of the manufacturing processes carried out in Old Nisa in connection with the production of decorative elements for the monumental complex located inside the citadel.
ABSTRACT A rapid, safe, and efficient procedure was developed to synthesize, on a small scale, fl... more ABSTRACT A rapid, safe, and efficient procedure was developed to synthesize, on a small scale, fluorinated chloroformates often required to perform analytical derivatizations. This new family of agents allows straightforward derivatization of highly polar compounds (with multiple hydroxy, carboxy, and amino substituents) in the aqueous phase, compatible with GC and GC/MS analysis. A goal of this work was to develop a derivatization procedure that would enable the detection and identification of highly polar disinfection by-products in drinking water.
A multitechnique (SEM-EDX, XRD, TGA) characterization was performed on several materials and arte... more A multitechnique (SEM-EDX, XRD, TGA) characterization was performed on several materials and artefacts from Old Nisa excavated during the recent Italian–Turkmen archaeological expedition, which involved a large building in the SW corner of the citadel, formed by rooms utilized as warehouses and workshops. Polygenic conglomer-ates archaeologically classified as anhydrites were examined and proved to be highly compatible with all the studied architectural artefacts (a plaster, a mortar, and a mould), making strongly plausible their identification as raw materials. Besides, several pigments at different stages of the manufacturing process were examined. A very complex situation emerged, suggesting the existence of different productive processes. At last, a black cylindrical object, identified as a seal, but almost completely devoid of engravings, turned out to be made of graphite and obtained by turning. The results of the analyses on these materials shed a new light on the complexity of the manufacturing processes carried out in Old Nisa in connection with the production of decorative elements for the monumental complex located inside the citadel.
Several plasters and mortars from the Middle Bronze Age site of Erimi- Laonin tou Porakou (Cyprus... more Several plasters and mortars from the Middle Bronze Age site of Erimi- Laonin tou Porakou (Cyprus) were analyzed in order to perform a technological characterization. Morphological (SEM), elemental (EDX), mineralogical (XRPD), petrographic (polarized OM, SEM-EDX), thermal (TGA) and spectroscopic (FTIR) techniques were applied.
Plasters and mortars were identified as pyrotechnological lime products, obtained using local raw materials and containing a moderate amount of spatic calcite aggregates. Use of organic fibers was ascertained and a seminal use of a hydraulic additive was evidenced.
SEM-EDS and XRF analyses of pellets produced with powdery clay and ceramic standards and fired at... more SEM-EDS and XRF analyses of pellets produced with powdery clay and ceramic standards and fired at increasing temperatures showed a systematic overestimation of the abundance of heavier detected elements (K, Ca, Ti and Fe) using the conventional procedure of calibration with massive mineral/glass certified materials followed by normalization of the detected values. Errors were particularly noticeable for samples fired in the typical range of temperatures of archaeological and historical pottery (600–900 °C) and for unfired samples, and were attributed to material porosity. An extremely simple method based on the SEM-BSE image analysis is proposed for the semi-quantitative evaluation of porosity. A remarkable increase of accuracy, especially for SEM-EDS, was evidenced when the calibration is performed using a standard with porosity comparable to the samples, with regard to the pottery temperature range. Conversely, for the analysis of high-fired samples simulating porcelain (1200 °C) no substantial difference was observed with respect to the usual massive minerals/glass calibration. Finally, results showed the unsuitability of calibration performed by means of unfired pellets, for both pottery and porcelains.
A multitechnique (SEM-EDX, XRD, TGA) characterization was performed on several materials and arte... more A multitechnique (SEM-EDX, XRD, TGA) characterization was performed on several materials and artefacts from Old Nisa excavated during the recent Italian–Turkmen archaeological expedition,which involved a large building in the SW corner of the citadel, formed by rooms utilized as warehouses and workshops. Polygenic conglomerates archaeologically classified as anhydrites were examined and proved to be highly compatible with all the studied architectural artefacts (a plaster, a mortar, and a mould), making strongly plausible their identification as raw materials. Besides, several pigments at different stages of the manufacturing process were examined. A very complex situation emerged, suggesting the existence of different productive processes. At last, a black cylindrical object, identified as a seal, but almost completely devoid of engravings, turned out to be made of graphite and obtained by turning. The results of the analyses on these materials shed a newlight on the complexity of the manufacturing processes carried out in Old Nisa in connection with the production of decorative elements for the monumental complex located inside the citadel.
ABSTRACT A rapid, safe, and efficient procedure was developed to synthesize, on a small scale, fl... more ABSTRACT A rapid, safe, and efficient procedure was developed to synthesize, on a small scale, fluorinated chloroformates often required to perform analytical derivatizations. This new family of agents allows straightforward derivatization of highly polar compounds (with multiple hydroxy, carboxy, and amino substituents) in the aqueous phase, compatible with GC and GC/MS analysis. A goal of this work was to develop a derivatization procedure that would enable the detection and identification of highly polar disinfection by-products in drinking water.
A multitechnique (SEM-EDX, XRD, TGA) characterization was performed on several materials and arte... more A multitechnique (SEM-EDX, XRD, TGA) characterization was performed on several materials and artefacts from Old Nisa excavated during the recent Italian–Turkmen archaeological expedition, which involved a large building in the SW corner of the citadel, formed by rooms utilized as warehouses and workshops. Polygenic conglomer-ates archaeologically classified as anhydrites were examined and proved to be highly compatible with all the studied architectural artefacts (a plaster, a mortar, and a mould), making strongly plausible their identification as raw materials. Besides, several pigments at different stages of the manufacturing process were examined. A very complex situation emerged, suggesting the existence of different productive processes. At last, a black cylindrical object, identified as a seal, but almost completely devoid of engravings, turned out to be made of graphite and obtained by turning. The results of the analyses on these materials shed a new light on the complexity of the manufacturing processes carried out in Old Nisa in connection with the production of decorative elements for the monumental complex located inside the citadel.
Several plasters and mortars from the Middle Bronze Age site of Erimi- Laonin tou Porakou (Cyprus... more Several plasters and mortars from the Middle Bronze Age site of Erimi- Laonin tou Porakou (Cyprus) were analyzed in order to perform a technological characterization. Morphological (SEM), elemental (EDX), mineralogical (XRPD), petrographic (polarized OM, SEM-EDX), thermal (TGA) and spectroscopic (FTIR) techniques were applied.
Plasters and mortars were identified as pyrotechnological lime products, obtained using local raw materials and containing a moderate amount of spatic calcite aggregates. Use of organic fibers was ascertained and a seminal use of a hydraulic additive was evidenced.
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Papers by Patrizia Davit
Old Nisa excavated during the recent Italian–Turkmen archaeological expedition,which involved a large building
in the SW corner of the citadel, formed by rooms utilized as warehouses and workshops. Polygenic conglomerates
archaeologically classified as anhydrites were examined and proved to be highly compatible with all the
studied architectural artefacts (a plaster, a mortar, and a mould), making strongly plausible their identification
as raw materials. Besides, several pigments at different stages of the manufacturing process were examined. A
very complex situation emerged, suggesting the existence of different productive processes. At last, a black cylindrical
object, identified as a seal, but almost completely devoid of engravings, turned out to be made of graphite
and obtained by turning.
The results of the analyses on these materials shed a newlight on the complexity of the manufacturing processes
carried out in Old Nisa in connection with the production of decorative elements for the monumental complex
located inside the citadel.
Plasters and mortars were identified as pyrotechnological lime products, obtained using local raw materials and containing a moderate amount of spatic calcite aggregates. Use of organic fibers was ascertained and a seminal use of a hydraulic additive was evidenced.
Old Nisa excavated during the recent Italian–Turkmen archaeological expedition,which involved a large building
in the SW corner of the citadel, formed by rooms utilized as warehouses and workshops. Polygenic conglomerates
archaeologically classified as anhydrites were examined and proved to be highly compatible with all the
studied architectural artefacts (a plaster, a mortar, and a mould), making strongly plausible their identification
as raw materials. Besides, several pigments at different stages of the manufacturing process were examined. A
very complex situation emerged, suggesting the existence of different productive processes. At last, a black cylindrical
object, identified as a seal, but almost completely devoid of engravings, turned out to be made of graphite
and obtained by turning.
The results of the analyses on these materials shed a newlight on the complexity of the manufacturing processes
carried out in Old Nisa in connection with the production of decorative elements for the monumental complex
located inside the citadel.
Plasters and mortars were identified as pyrotechnological lime products, obtained using local raw materials and containing a moderate amount of spatic calcite aggregates. Use of organic fibers was ascertained and a seminal use of a hydraulic additive was evidenced.