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61.
This paper presents research into the identification of tobacco residues in ancient smoking pipes. Two techniques have been used so far: gas chromatography/mass spectroscopy (GC/MS), and Raman microscopy. GC/MS has been used successful in the past by the author to identify ancient tobacco residues, and the results of this round of analysis support prior research. Raman microscopy, which has the advantage of working on dry samples without solvents, was not successful. It appears that combustion products overwhelm any useful signal that would identify the substance smoked. We are pursuing the use of Raman in non-combusted samples.  相似文献   
62.
The present paper reports the chemical data obtained on samples of pigmenting materials contained in 31 miniature vessels found in a burial found in Teopancazco, a multiethnic neighborhood center located in the southeastern sector of the archaeological site of Teotihuacan (Central Mexico) and the analytical protocol established for the complete characterization of these archaeological materials. For this purpose a multi-technique approach based on the combination of several non destructive and micro-destructive instrumental techniques, namely, light microscopy (LM), scanning electron microscopy-X-ray microanalysis (SEM-EDX), transmission electron microscopy (TEM), voltammetry of microparticles (VMP), X-ray microdiffraction (μXRD), X-ray diffraction (XRD), UV-Vis spectrophotometry, FTIR spectroscopy and gas chromatography-mass spectrometry (GC-MS) has been developed in an attempt to completely characterize these materials. These instrumental techniques provide reliable and complementary data including elemental and mineralogical composition, identification of functional groups as well as speciation studies of electroactive species. Among the most relevant findings, volcanic pyroclastic rocks and clayey soils, most probably, from the Teotihuacan valley as well as galena, jarosite and mica from other provenances in Mesoamerica, have been identified. Charcoal and Ocote resin have also been identified. The chemical composition of the samples is discussed with a view to the possible function as cosmetic materials and their use in funerary rites. The results have been critically compared with those others obtained in other ancient civilizations. The study carried out on the materials found in the burial 105 is especially relevant insofar it represents the first evidence, scientifically characterized, of the use of cosmetics in Mesoamerica at this early period (AD 200-550).  相似文献   
63.
Ultrastructural features of deep, intermediate and superficial enamel were quantitatively assessed for the mandibular first permanent molars of 10 specimens each of the domestic sheep (Ovis aries) and goat (Capra hircus). The means of a number of variables differed interspecifically at high levels of statistical significance, especially with regard to the enamel of intermediate depth. A canonical discriminant function analysis employing nine variables at all three enamel depths resulted in the correct taxonomic assignment of 95% of the specimens comprising the present sample. These results, coupled with the simple preparative and analytical methods presented here, may enable archaeozoologists to utilize enamel ultrastructure in order to discriminate between fragmentary dental remains of these caprine species.  相似文献   
64.
This paper presents the results of analyses carried out on the paintings on the rock‐hewn walls of the Forty Martyrs church at ?ahinefendi in Cappadocia (a UNESCO World Heritage Site), a central region of Turkey, performed during conservation work from 2007 to 2012. The micro‐samples were investigated by spectroscopic, micro‐stratigraphic and scanning electron microscopy analysis in order to study the painting technique, the materials and the degradation products. The micro‐stratigraphic analysis showed a white, sometimes pinkish, plaster. Micro‐Raman analysis, performed on cross‐sections of the mortars, enabled the detection of calcite, gypsum, anhydrite and calcium oxalate. Scanning electron microscopy and energy‐dispersive spectroscopy revealed a similar composition among all investigated phases, aside from minor differences such as the presence of diatoms in the second and third phases and of biotite, lime lumps and plants fragments in the fourth one. Apart from traditional pigments of medieval wall paintings, micro‐Raman analysis revealed the presence of lead‐based compounds and jarosite.  相似文献   
65.
Here, we report the physico‐chemical characterization of wall paintings from the Petros and Paulos church in Ethiopia. This work represents the first technical study of paintings located in Ethiopia, rather than paintings in museum collections outside the country, using diverse analytical techniques. In situ examination with a portable X‐ray fluorescence spectrometer (pXRF) was followed by analysis of samples using optical microscopy (OM), scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy (SEM/EDS), micro‐Raman spectroscopy (MRS), attenuated total reflection – Fourier transform infrared spectroscopy (ATR‐FT–IR), X‐ray powder diffraction (XRD) and pyrolysis gas chromatography – mass spectrometry (Py‐GC/MS). The paint stratigraphy, the compositions of the support material, the preparatory and painting layers were studied, as well as the morphology of the pigment particles. The results revealed the use of earth pigments and carbon black. The preparatory layer was uncommon; composed of dolomite, clay rich in clinochlore and sand, in contrast to the more common gypsum and calcite. The binder and the stratigraphic analyses suggested a distempera technique.  相似文献   
66.
Owing to its resistance to degradation, hair is an important bio-sample with unique properties used to study post mortem decompositional changes. The present paper is a microscopical approach to preserved human scalp hair discovered at the 18th–19th-century archaeological site of Iași, Romania. The hair fibre alterations were assessed using optical microscopy, scanning electron microscopy, image analysis and hair histological scores. External alterations showed a statistically significant heterogeneous degradation. Image analysis results of the internal degradation of hairs were correlated to external lesions. The results consider the implication of intrinsic biological factors in the post mortem degradation of human hair preserved in graves with comparable environmental conditions.  相似文献   
67.
Six ninth-century stucco fragments from Samarra, Iraq, and now part of the Victoria and Albert Museum collections, were analysed non-destructively and in situ in the Museum by Raman microscopy in order to determine the identities of the pigments thereon. Carbon black, haematite, gypsum, indigo, lazurite, lead white, orpiment, pararealgar, red lead, vermilion and the As4S4 χ-phase were detected. The detection of several arsenic-containing pigments (orpiment, pararealgar and the As4S4 χ-phase), known to be poisonous and carcinogenic, has prompted strict health and safety protocols to be used when the objects are handled by museum staff or displayed in the galleries. This scientific study is the first to be carried out on any of the Samarra finds.  相似文献   
68.
Archaeological excavations and multidisciplinary studies at the site of Dmanisi (Lesser Caucasus, Georgia) have provided an assemblage of lithic artefacts and numerous palaeontological and human remains in a volcano-sedimentary context dating to the early Lower Pleistocene. The sieving of archaeological sediments from Dmanisi also yielded mineralised botanical macro-remains that were analysed according to a particular protocol. The use of scanning electron microscopy (SEM) allowed the comparison between fossil fruit remains and modern specimens, leading to a precise identification of the earlier. Seed remains recognised by this method belonging to several taxa from the Boraginaceae family as well as to the genus Celtis L., of the Ulmaceae family. The ecological requirements of these taxa suggest the presence of xeric conditions, a result that is in accordance with data obtained by faunal and stratigraphic studies.  相似文献   
69.
Apulian red figured pottery samples, dating back to the 5th and 4th centuries BC, from the archaeological site of Monte Sannace (Gioia del Colle, Bari, Italy) have been characterized from the physical–chemical, mineralogical and morphological points of view. Scanning electron microscopy, X-ray diffraction and atomic spectroscopy investigations have been carried out on the ceramic body, red decorated area and black gloss of the fragments, with the aim of outlining the technological features and of defining the nature of coatings and decorations. All 5th century fragments show the same features: fine texture of the ceramic body, red figures saved from the ceramic paste and black gloss painted directly on the ceramic body. The statistical treatment of compositional data of ceramic bodies excludes the local production of these objects. As regards the 4th century fragments, some show similar features to the 5th century ones; however others are characterized by the coarse texture of their ceramic body and an intermediate red layer of finer clay between the black gloss and the ceramic body. The analytical results make it possible to distinguish two different production technologies of red figured Apulian vases in Monte Sannace during the 4th century BC. Certain vases were produced using the “classic” Attic technology and others with a different technique, not previously known, which involved the application of a red engobe layer on the clay paste, before the black gloss painting.  相似文献   
70.
The key problem restricting lithic microwear analysis is the lack of quantitative analysis to support qualitative assessments of different wear traces. This paper presents the reflective laser scanning confocal microscope (LSCM) as a new technique for the study of lithic microwear that has the potential to resolve this problem. Firstly, an example is presented that shows how the LSCM compares with conventional reflected light microscopy and scanning electron microscopy. This shows that images, rivalling that of the SEM, can be produced in similar timescales to conventional photomicrography and with no need for casting or sample preparation. The LSCM is also used to measure surface roughness of use-wear produced from working hide (dry, fresh and greasy), woodworking and antler working. This analysis demonstrates clear differences between the different wear polishes and the potential of the LSCM as a quantitative approach in lithic microwear research.  相似文献   
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