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991.
    
This special section examines the possibility of meaningful debate and contestation over urban decisions and futures in politically constrained contexts. In doing so, it moves with the post‐political times: critically examining the proliferation of deliberative mechanisms; identifying the informal assemblages of diverse actors taking on new roles in urban socio‐spatial justice; and illuminating the spaces where informal and formal planning processes meet. These questions are particularly pertinent for understanding the processes shaping Australian cities and public participation today.  相似文献   
992.
    
Previous research has shown that Iznik glazes are characterized by low potash and magnesia contents. It was therefore suggested that the flux used was either a purified plant ash or some unidentified mineral source of soda. More recently, as a result of the detection of small, but significant, amounts of boron and lithium in Byzantine glasses from western Turkey, which also exhibit low potash and magnesia contents, it has been suggested that the source of the flux used was a soda‐rich evaporite associated in some way with the extensive borax deposits in the region. LA–ICP–MS has been used to establish that Iznik glazes also contain similarly small amounts of boron and lithium. The Na/K, Na/Mg, Na/Ca and Na/B ratios for these Iznik glazes are shown to be comparable to the equivalent ratios calculated from published data for waters from a range of Na–HCO3 type hot springs in western Turkey, with the closest match being to the hot springs around Afyon‐Gazligöl, which is consistent with documentary evidence. It is therefore proposed that the soda‐rich salts produced by evaporating water from these springs to dryness would have provided the flux required for the production of Iznik glazes and high‐boron Byzantine glasses.  相似文献   
993.
    
A coated Roman iron coin from Villa Loig in Salzburg, Austria was investigated. The coating is a copper alloy consisting of Cu, Pb, Sn, Zn and negligible amounts of Ag, a variant of gunmetal known as ‘leaded red brass’. The numismatic term for such a coin is subferratus (Latin). From an archaeometallurgical point of view, information about the chemical composition, the microstructure and the manufacturing technique are of interest. To achieve these objectives, different analytical techniques and metallographic examinations were applied. Droplet‐shaped iron inclusions were observed in the red brass coating, while at the grain boundaries, inside the iron core, copper and lead were detected (liquid metal embrittlement). The dendritic microstructure of the coating, the spheroidal‐shaped iron inclusions in the coating and the liquid metal embrittlement show that the iron coin was plated by immersing it in a molten copper alloy. The iron core is a low‐carbon steel with slag stringers, both of which are characteristic of a bloomery iron. Deformation twins (Neumann lines) were observed in the microstructure of the iron core and indicate that the coining was performed after the flan was cooled.  相似文献   
994.
    
A group of 18 cameos dated from the 16th to 19th centuries (bearing motifs of Roman emperors and female members of their families) from the Constantine Schmidt‐Ci??yński collection was investigated with gemmological analyses, supported by non‐destructive mineralogical methods such as X‐ray diffraction (XRD) and micro‐Raman spectroscopy (RS) to ascertain the material used. Although there is no scientific method to date the specimens precisely, the mineralogical data supported by archaeological analyses enabled the estimation of the possible timing of the manufacture of the gems. As a result, the cameos were divided into four basic chronological groups: (1) Renaissance, (2) Baroque, (3) uncertain and (4) Classical and Neoclassical.  相似文献   
995.
    
Slipped and unslipped wares from Kampyr Tepe dated to the Hellenistic–Seleucid and Greco‐Bactrian periods stylistically resemble tableware from the Greek tradition. Since two pottery workshops have been recovered at the site, the aim is to shed light on the provenance and the production and consumption patterns of the tableware, as well as on the degree of technological influence from Hellenistic–Mediterranean traditions. The archaeometric characterization, consisting of thin‐section petrography, XRF, XRD and SEM–EDS analysis, was performed on 44 wares and three unfired locally made pondera, which were used as reference local elemental patterns. The study demonstrated the local origin of most of the wares, which were produced using a similar clay paste, following standardized techniques in modelling and firing, while surface treatments appear to be more diversified.  相似文献   
996.
    
Radiogenic lead and strontium isotope data are presented for lead‐ and calcium carbonate/barium sulphate‐containing paint and ground samples from 15 paintings, executed between 1844 and 1871, by 19th‐century Canadian artist Cornelius Krieghoff. Like many artists of this era, Krieghoff used lead‐based pigments such as lead white, chrome yellow and Naples yellow, and extenders such as calcium carbonate and barium sulphate. The lead isotope analyses of the majority of these pigments are consistent with the isotopic compositions of lead mined from European lead deposits in England and/or Germany. However, three samples from Krieghoff's early career yield lead isotope compositions that are much more radiogenic than European sources. The lead isotope compositions of these three samples are consistent with the addition of a more radiogenic lead component that is similar to the lead derived from North American lead deposits in Missouri and Illinois (Mississippi Valley Pb–Zn type deposits). The strontium isotope compositions of the extenders suggest that the raw materials for calcium carbonate or barium sulphate extenders were largely derived from Palaeozoic to modern‐day marine environments. This study shows that pigments manufactured from North American lead were being incorporated into Canadian paintings as early as 1844.  相似文献   
997.
    
With the introduction of commercially available handheld XRF analysers, there is a growing problem that the results, simply taken at face value, are regarded as representative of the bulk gold alloys of the objects analysed in museums and used for treasure analysis. It is well known that surface analysis is problematic, and the aim of this study was to test whether non‐destructive surface analysis could be useful in grouping the very large numbers of fragmentary pieces in the Anglo‐Saxon Staffordshire Hoard. Surface and subsurface analyses of 16 objects from the Hoard were carried out by X‐ray fluorescence (XRF) and scanning electron microscopy with energy‐dispersive X‐ray analysis (SEM–EDX). The results indicate that there are significant but inconsistent levels of enrichment of the gold at the surface of many of these objects, due to the loss of both copper and silver. The significant loss of silver (up to 50% relative in some cases) suggests that some form of deliberately induced depletion gilding was carried out during manufacture to remove both silver and copper from the surface. In three cases, an increase in silver at the surface compared to the core metal was detected: this might tentatively be explained by redeposition from contact with silver objects during burial. These results have clear implications for the reliability and interpretation of surface analysis data of gold alloys from this period.  相似文献   
998.
    
T. J. Booth 《Archaeometry》2016,58(3):484-499
A central problem in funerary archaeology is interpreting how the corpse was manipulated in the immediate post mortem period. The extent of bacterial bioerosion to the internal bone microstructure has been proposed as a means to infer the early post mortem history of a corpse, as it has been suggested that this form of bone diagenesis is produced by an organism's putrefactive gut bacteria. Under this model, different forms of funerary treatment would be expected to leave characteristic signatures of bioerosion in archaeological bone. Here, we tested the extent to which bacterial bioerosion of ancient human bones reflected funerary treatment, through histological analysis of 301 archaeological human bone thin sections from 25 European archaeological sites. We found that bioerosion was significantly influenced by whether a bone originated from a neonatal individual or an anoxic context. When these remains were excluded, bioerosion was controlled by archaeological phase in a manner consistent with known early post mortem treatment and forensic models of bodily decomposition. These findings suggest that microscopic analyses of bone have useful applications in reconstructions of funerary processes and provide some insight into factors that may control the persistence of organic biomolecules and fossilization.  相似文献   
999.
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