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This study deals with the mineralogical and chemical characterization of archaeometallurgical material from the Roman archaeological site of Castra (Ajdov??ina, western Slovenia). Samples were initially analysed via optical microscopy and X‐ray powder diffraction, with the composition of individual phases then determined using scanning electron microscopy coupled with electron‐dispersive spectroscopy, and Raman microspectroscopy. Chemical investigation was carried out by using inductively coupled plasma atomic emission spectroscopy to measure the major element content. The results showed that the slag originated from iron smithing operations, with calcium‐rich olivines, as well as wuestite and leucite, the most abundant phases. The investigated slags were also found to be characterized by significantly high lime levels, which probably promoted the formation of the calcium‐rich olivines.  相似文献   
996.
In China, there are places that are rich in gem‐quality turquoise resources, including north‐west Hubei Province and the nearby Baihe County in Shaanxi Province, and many ancient mining sites, although the mining history remains a mystery. Based on the compositional data from reference samples of known deposits, a comparison of the major and trace element contents of archaeological turquoise may help with determination of artefact provenance. This paper discusses new evidence of provenance‐tracking of turquoise in this area, obtained from geochemical analyses using REE and other trace elements of 22 turquoises and their surrounding rock samples from six ancient mines and three archaeological sites. The results indicate that the three archaeological turquoises from the tomb of the Middle Spring and Autumn Period (580–560 bc ) and the Warring States Period (476–221 bc ) in Hubei Province were made of raw material from north‐west Hubei Province and the nearby Baihe County in Shaanxi Province. [Correction added on 29 October 2014, after first online publication: In the preceding sentence, the correct dates for the Middle Spring and Autumn Period, and the Warring States Period have been added]  相似文献   
997.
The burials of famous Xiongnu people are a unique source of information about Xiongnu culture, due to the variety of organic findings. SRXRF analysis of hair, clay, bones, teeth and woollen cloth was carried out. An anomalously high copper content was observed in all hair samples, whereas the levels of copper in bone and clay were low. To define the hair morphology and the elemental distribution in the hair cross‐section, high‐resolution X‐ray computed tomography (HRXCT) and energy‐dispersive spectroscopy (EDS) with scanning electron microscopy (SEM) were used. The X‐ray absorption fine‐structure method (XAFS) was applied to determine the local copper environment. The majority of the copper species in the hair and enamel samples are present as Cu2+ cations in a distorted octahedral (4 + 2) coordination, surrounded by light ligands (oxygen/nitrogen). A similar distorted octahedral coordination is typical for both inorganic mixed oxide/hydroxide Cu nanosystems and metal–organic Cu complexes (with oxygen/nitrogen).  相似文献   
998.
Pattern‐welding is a well‐known technique that was widely employed in the manufacture of swords. While the decorative effect of genuine pattern‐welding (employing phosphoric iron) is indisputable, to date its reinforcing effect is rather unclear. In order to understand this issue better, wrought iron, phosphoric iron, steel and various pattern‐welded samples were prepared and mechanically tested, and the results obtained are discussed in detail. Both the mechanical testing and the long‐term metallographic investigation of medieval swords suggest that pattern‐welding does not have any significant positive effect on the mechanical properties of swords and we should consider it a primarily decorative technique.  相似文献   
999.
Research recommenced at Tell Abraq in 2007, carried out by Bryn Mawr College with an international team in co‐operation with the Sharjah Archaeology Authority. Between 2007 and 2010 fieldwork was limited to documenting sections of the previous excavations and one small sounding while our attention focused mainly on the nearby shell‐midden site of Hamriya and the fortified Iron Age settlement site of Muweilah. Since 2010, large‐scale excavations have been conducted which have fundamentally altered our understanding of the layout of the settlement and its economic relations during the second and first millennia BC. In this report, we detail the results of this work and present preliminary interpretations.  相似文献   
1000.
Parents raising a child with a physical or cognitive disability are often faced with the negative stigma against disabilities that exist in several Arab countries. This puts extra pressure on the parents and can lead to negative outcomes for the children. The purpose of this study was to investigate the effects of parenting stress and varying levels of support for mothers of children with disabilities and the effects of these pressures on their relationship with their disabled child. We surveyed 85 Kuwaiti mothers of children with disabilities. The participants filled out an online survey with questions regarding parenting related stress, perceived social support, feelings of social isolation, self‐efficacy, and attachment to their child. Results indicate that mothers who feel unsupported by their families, community, and government experience more parenting stress and greater social isolation. These in turn lead them to feel less competent in their parenting abilities, and ultimately they feel less emotionally connected to their child. Implications of these findings are discussed.  相似文献   
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