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The Chemical Composition and Production Area of Early Western Zhou Proto‐Porcelain Unearthed from Yejiashan Cemetery,Suizhou, China 下载免费PDF全文
The bodies and glazes of 27 early Western Zhou proto‐porcelain samples from Yejiashan cemetery, Hubei Province, were analysed using LA‐ICP–AES, SEM, XRD, a thermal expansion instrument and other analytical methods. The results indicated that the bodies of all samples were characterized by high silicon and low aluminium, and were made with porcelain stone raw materials found in the south of China. The glazes are typical of high‐temperature calcium glazes of the CaO (MgO) – K2O (Na2O) – Al2O3 – SiO2 series, with relatively high Mn and P content, which was probably caused by the addition of plant ashes. The physical properties and phase compositions of Yejiashan proto‐porcelain show that firing processes were still in the early stages of development in ancient China. Multivariate statistical analyses indicated that Yejiashan proto‐porcelain might have come from the Deqing area, in Zhejiang Province. These results provide new archaeological evidence for research on issues related to material flow in the Western Zhou dynasty. 相似文献
154.
An Approach to the Diagnosis of Craniofacial Fibrous Dysplasia from the 2500‐Year‐Old Remains of a Skull from Ancient China 下载免费PDF全文
K. L. Cheng H. Shao D. Zhao B. T. Sun J. Yu Z. C. Sun M. C. Li L. Guo H. Zhu Q. C. Zhang Y. H. Huang 《Archaeometry》2018,60(1):171-182
A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases. 相似文献
155.
Antonia C. Settle 《Development and change》2018,49(5):1291-1313
Based on extensive fieldwork, this article examines new informality in Pakistan's land market by which vacant plots of land are transacted informally between market actors in rapidly reversed short‐term holdings. The analysis pivots around the changing economic environment in Pakistan with the shift from heavy regulation of money and controlled pricing, to the liberalization of money and markets. The author explores how liquidity is taken up as a microeconomic strategy to protect against new financial risk in this environment, and how this is played out as a preference for informal transactions. These practices inform a case study that contributes to the established literature on the links between globalization and the informal economy by articulating a driver of growing informal transactions that is novel to the literature. 相似文献
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Recent years have seen an increase in location privacy research, including the application of geomasking procedures. Geographical masks aim to protect privacy and preserve spatial information through the displacement of point data. False identification, or the mistaken association of data with the incorrect person or household, is an unexplored issue in geomasking, despite legal protections against false association. This study introduces a topological framework for assessing identification risk and examines the risk of false identification in four masking techniques: random perturbation, donut masking, and the newer Voronoi and MGRS masking techniques. While Voronoi masking is found to best preserve the clustering properties of a sample of urban foreclosure data, the other three masking techniques result in better protection against correct and false identification. 相似文献
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J. C. Obando 《Journal of Earthquake Engineering》2018,22(4):569-594
This paper describes a study on the characterization of the Inelastic Displacement Ratios (IDRs) of inelastic acceleration-sensitive nonstructural components subjected to floor accelerations obtained from the linear analysis of multistory building structures under far-field ground accelerations. Several building models having different structural systems and a number of stories were considered. IDRs were obtained from the displacement response of elastic and inelastic single-degree-of-freedom systems subjected to floor accelerations. Similarities and differences between floor acceleration IDRs and ground acceleration IDRs were identified, and efforts were made to explain the differences. Finally, a predicting equation for floor acceleration IDRs is proposed and validated. 相似文献
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Biological invasions are one of the great threats to Earth’s ecosystems and biodiversity in the Anthropocene. However, species introductions and invasions extend deep into the human past, with the translocation of both wild and domestic species around the world. Here, we review the human translocation of wild plants and animals to the world’s islands. We focus on establishing criteria used to differentiate natural from human-assisted dispersals and the differences between non-native and invasive species. Our study demonstrates that, along with a suite of domesticates, ancient people transported numerous wild plants and animals to islands and helped shape ecosystems in ways that have important ramifications for modern conservation, restoration, and management. 相似文献