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951.
D. HRADIL J. HRADILOVÁ E. KOČÍ S. ŠVARCOVÁ P. BEZDIČKA J. MAŘÍKOVÁ‐KUBKOVÁ 《Archaeometry》2013,55(4):691-706
Pre‐Romanesque murals at Kosto?any pod Tríbe?om, Slovakia, have been investigated by portable X‐ray fluorescence and by microanalytical methods to identify painting materials (pigments and binders), and to explain the degradation of colours. Today, missing green and blue shades have been reconstructed according to residual concentrations of Cu, which correspond to copper chlorides—products of salt corrosion of the copper carbonates azurite and/or malachite, accelerated by micro‐organisms. As confirmed by powder X‐ray microdiffraction, original minium (Pb3O4) has been transformed to brown–black plattnerite (PbO2). In increased humidity, even insoluble pigments are washing down from the walls and the intensity of colours further diminishes. 相似文献
952.
Gang Meng G. Brent Hall Mary E. Thompson Patrick Seliske 《The Canadian geographer》2013,57(2):154-172
This study assesses the overall spatial variations and neighbourhood‐level “hot spots” of low birth weight and preterm birth incidence within three public health units in Ontario, Canada. The analysis uses a stepwise approach of intra‐class correlation analysis, a spatial scan statistic, and multilevel spatial modeling. Results show that neighbourhood level variation accounts for only 2–3 percent of the total variation of adverse birth outcomes in the study area. However, strong spatial autocorrelation is observed at the neighbourhood level, and spatial clusters of relatively high adverse birth outcome rates exist in areas that are associated with environmental risks, including pollution sources and proximity to highways. Thus, although estimated neighbourhood impacts on adverse birth outcomes are small compared with those of individual‐level risks, local high potential environmental risk areas are identifiable. Environmental surveillance and spatial statistical analysis should be conducted regularly by local health authorities to identify and monitor the impact of environmental changes on health in general and on birth outcomes in particular. Specific community‐oriented health interventions may be required to reduce observed local health impacts. 相似文献
953.
Identification of the volcanic material (pozzolan) stored in a Roman ship of the fourth to third century bce , wrecked in the ancient harbour of Pisa (central Italy), was based on ratios of selected trace elements. The compositions of the major volcanic products erupted by the volcanoes of the Roman province, including the volcanic districts of Latium (Vulsini, Vico, Monti Sabatini and the Alban Hills) and Campania (Roccamonfina, the Phlegraean Fields, Ischia, Procida and Vesuvius) are compared with the pozzolan from the Pisa ship. Superposition of the Zr/Y, Nb/Y and Nb/Zr ratios of the pyroclastic material from the wrecked ship (computed from the published literature) allows correlation with the products of the Onano eruption from the Vulsini Volcanic District. The Vulsini rocks outcrop extensively in a sector drained by the hydrographic network of the Fiora River, which has been a well‐developed commercial water trade route since Etruscan times, with a river port and a sea port connected to the important town of Vulci, and, since 273 bce , part of the larger Roman harbour system of Cosa. 相似文献
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Archaeological bone undergoes alterations after burial (diagenesis) that constitute a problem for the survival of archaeological information. A common method to assess this alteration is Fourier transform infrared spectrometry (FTIR). However, the commonly applied method (FTIR–KBr) is destructive and sample preparation may influence the results. This paper tests the suitability of FTIR attenuated total reflection (FTIR–ATR), a method not commonly used to investigate bone diagenesis. FTIR–ATR requires less sample preparation and can be non‐destructive, allowing analysis of bone cross‐sections. Modern and archaeological bones were analysed using both methods and different sample preparation methods were tested. The results show that FTIR–ATR has advantages for the rapid assessment of bone diagenesis. 相似文献
956.
This study explores the potential of carbon and oxygen isotope data from human enamel carbonate (n = 50) to contribute to mobility studies in the Caribbean. Most oxygen and carbon isotope results display limited variation, with substantial overlap between islands. However, a few individuals from El Chorro de Maíta, Cuba possess relatively low δ18O and high δ13C. Two of these individuals were previously identified as possible non‐Antillean immigrants on the basis of strontium isotopes, and bioarchaeological and mortuary evidence. The carbon and oxygen isotope results provide additional evidence supporting the proposed non‐local origins of these individuals and contribute to explorations of their potential natal origins. 相似文献
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