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41.
关于秦始皇帝陵出土彩绘青铜水禽铜矿料来源的研究,对进一步研究秦代的物质文化、青铜器冶铸工艺、装饰工艺以及铜矿来源均具有重要意义。本研究对部分秦始皇帝陵园出土彩绘青铜水禽基体进行了铅同位素分析及微量元素分析。并在此基础之上,与甘肃东部及关中西部出土的部分早期秦文化铜器、国墓地出土的部分铜器、周原李家铸铜作坊出土的部分铜器、山西中条山、江西瑞昌、江西铜岭、安徽铜陵以及湖北大冶铜绿山古铜矿以及秦岭山区的部分现代铜矿的相关数据进行了对比研究。结果发现,秦始皇帝陵园出土的青铜水禽使用了相同的矿料,且与绝大多数早期秦文化铜器所使用的矿料基本相同,但与国墓地以及李家铸铜作坊出土西周铜器的矿料明显有别。秦人使用的铜矿与秦岭山区现代铜矿较为接近,表明秦人的铜矿来源可能与秦岭山区有关。  相似文献   
42.
What's in a bone? Recent advances in archaeological bone chemistry   总被引:2,自引:0,他引:2  
This paper focuses on advances in archaeological bone chemistry since 1989. At that time studies generally shifted from development and application of techniques in bone chemistry to more experimental approaches. In stable isotope studies, controlled feeding experiments have been carried out to determine the routing of various dietary components into bone tissues. Biological apatite has been added to collagen as a tissue of study for stable carbon isotope analysis, providing the ability to study much older remains. Other elements have been added such as hydrogen for the study of paleoclimate and oxygen and strontium isotopes to study life history. Trace element studies have focused on methods of detecting and controlling for diagenesis, and barium has been added to the list of useful dietary indicators. Attempts to extract DNA from archaeological bone have been successful, however, this field is still in its early stages in terms of applications to understanding prehistoric biological relationships.  相似文献   
43.
ABSTRACT

Many biblical stories exhibit an intentional association between “subjective facts” deriving from the narrative and “objective facts” belonging to external historical reality. This article examines stories belonging to the “departure on a journey” pattern which contain references to objective facts which follow a virtually fixed formula and occur at a standard location in the narrative. Both the frequency with which these facts are adduced and their formulaic nature make it difficult to adopt external criteria such as those proposed by either of the two conventional models (aetiological and communication), suggesting rather an inner—literary—link between the two sets of facts.  相似文献   
44.
The paper describes the formulation of a non-linear, two-dimensional beam finite element with bending, shear and axial force interaction for the static and dynamic analysis of reinforced concrete structures. The hysteretic behaviour of “squat” reinforced concrete members, in which the interaction between shear and flexural deformation and capacity is relevant for the overall structural performance, is emphasised. The element is of the distributed inelasticity type; section axial-flexural and shear behaviours are integrated numerically along the element length using a new equilibrium-based approach. At section level a “hybrid” formulation is proposed: the axial-flexural behaviour is obtained using the classic fibre discretisation and the plane sections remaining plane hypothesis, the shear response instead is identified with a non-linear truss model and described with a hysteretic stress-strain relationship. The latter contains a damage parameter, dependent on flexural ductility, that provides interaction between the two deformation mechanisms. The element has been implemented into a general-purpose finite element code, and is particularly suitable for seismic time history analyses of frame structures. Analytical results obtained with the model are compared with recent experimental data.  相似文献   
45.
Contents of selenium (Se) were determined in human skeletal remains of prehistoric populations by in situ trapping of Se hydride by ET AAS (atomic absorption spectrometry with electrothermal atomisation). Dr Korunová worked out a method of determination of Se in preparation. The method of determination of Se was verified by means of radioactive indicator 75Se incorporated in the tissues of laboratory animals. Detection limit of the method was 23 pg Se. Se is another element suitable for dietary reconstruction in past populations as it relates to the consumption of meat in a similar way to zinc. Through the analysis of Se, we were able to distinguish between Eneolithic archaeological cultures (Corded Ware ceramic, Bell Beaker culture) and Bronze Age cultures (Protounětice, Starounětice, Unětice cultures). Significant differences were found in the levels of Se in the bones of individuals derived from the Bell Beaker and Uneětice Cultures, to the 95% confidence interval. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
46.
We investigated fossil tooth enamel of mammals and crocodiles from two Mio-Pliocene East-African formations (Lukeino and Mabaget Fms) using infrared spectroscopy and chemical and stable-isotope analyses. Infrared spectra indicate that the fossil enamel contains biological apatite (bioapatite), without significant secondary carbonate contaminations. Several empirical infrared indexes were used to analyze the crystal–chemical characteristics of enamel. Fossil enamel has less organic matter, water and structural carbonate of apatite than modern enamel with which it was compared. Fossil apatite has a better crystallinity than bioapatite. The calcium/phosphorus mass ratio and the fluorine content of fossil apatite show intermediate values between bioapatite and geological fluorapatite. The samples also display significant crystal-chemical variations, depending on the vertebrate group (mammals vs. reptiles) and the taphonomic context (Lukeino Fm vs. Mabaget Fm). In spite of these changes, no relationship was observed between the chemical contents (carbonate and fluorine) and the stable-isotope ratios of carbonate (δ13C and δ18O) in fossil enamel. Preservation of the palaeoenvironmental signals is strongly supported by the fact that the stable-isotope composition of the three investigated fossil mammalian taxa (deinotheres, equids and hippos) is consistent with their ecological features. For instance, typical C3- and C4-plant isotope compositions are reflected in the deinotheres and equids, respectively, and amphibious hippos display lower δ18O values than terrestrial herbivores, as expected.  相似文献   
47.
Calcite veins in Paleoproterozoic granitoids on the Baltic Shield are the focus of this study. These veins are distinguished by their monomineralic character, unusual thickness and closeness to Neoproterozoic dolerite dykes and therefore have drawn attention. The aim of this study was to define the source of these veins and to unravel their isotopic and chemical nature by carrying out fine‐scale studies. Seven calcite veins covering a depth interval of 50–420 m below the ground surface and composed of breccias or crack‐sealed fillings typically expressing syntaxial growth were sampled and analysed for a variety of physicochemical variables: homogenization temperature (Th) and salinity of fluid inclusions, and stable isotopes (87Sr/86Sr, 13C/12C, 18O/16O), trace‐element concentrations (Fe, Mn, Mg, Sr, rare earth elements) and cathodoluminescence (CL) of the solid phase. The fluid‐inclusion data show that the calcites were precipitated mainly from relatively low‐temperature (Th = 73–106°C) brines (13.4–24.5 wt.% CaCl2), and the 87Sr/86Sr is more radiogenic than expected for Rb‐poor minerals precipitated from Neoproterozoic fluids. These features, together with the distribution of δ13C and δ18O values, provide evidence that the calcite veins are not genetic with the nearby Neoproterozoic dolerite dykes, but are of Paleozoic age and were precipitated from warm brines expressing a rather large variability in salinity. Whereas the isotopic and chemical variables express rather constant average values among the individual veins, they vary considerably on fine‐scale across individual veins. This has implications for understanding processes causing calcite‐rich veins to form and capture trace metals in crystalline bedrock settings.  相似文献   
48.
The aim of this study is to further the discussion as to whether copper was extracted locally or imported to Sweden during the Bronze Age or if both of these practices could have coexisted. For this purpose, we have carried out lead isotope and chemical analyses of 33 bronze items, dated between 1600BC and 700BC. Among these are the famous Fröslunda shields and the large scrap hoard from Bräckan and other items from three regions in southern Sweden which are also renowned for their richness in copper ores. It is obvious from a comparison that the element and lead isotope compositions of the studied bronze items diverge greatly from those of spatially associated copper ores. Nor is there any good resemblance with other ores from Scandinavia, and it is concluded that the copper in these items must have been imported from elsewhere. The results furthermore indicate that there are variations in metal supply that are related to chronology, in agreement with other artefacts from Scandinavia as well as from other parts of Europe. Altogether these circumstances open up for a discussion regarding Scandinavia’s role in the maritime networks during the Bronze Age.  相似文献   
49.
The aim of this study was to define a strategy for a correct selection of bone samples by employing inductively coupled plasma optical emission spectroscopy (ICP-OES) for reconstructing the biological mineral content in bones through the determination of major elements, trace elements and Rare Earth Elements (REE, lanthanides) in skeletal cremains of ancient Iberians (III–II B.C), discovered in the Necropolis of Corral de Saus (Moixent, Valencia) between 1972 and 1979. The biological mineral content was determined taking into account diagenetic factors. A control method for a better reading of results was applied. To explore large geochemical datasets and to reduce the number of variables, Principal Component Analysis (PCA) was used, thus, providing a deeper insight into the structure of the variance of the dataset. PCA shows that the elemental profiles of bone and soil samples are clearly different. Bone samples obtained from the outer bone layer were shown to have a different elemental composition; more similar to soil samples than samples of the inner bone layer. PCA scores and loadings plots were preferred to dendrograms obtained using Cluster Analysis, due to the limits of the latter one to appreciate the spatial ordering of samples. Partial least squares discriminant analysis (PLS-DA), a frequently used supervised classification method, was applied to differentiate between degradation states of bone samples. PLS-DA results obtained in this study confirmed that changes derived from different burning conditions were associated with transformations in the mineral part of the bones. Accordingly, carbonized bones can be differentiated from cremated bones. Class assignment of bone samples with uncertain thermal conditions in dependence on their elemental composition has shown to be feasible. Consequently, for biochemical-archaeological studies the analysis and statistical classification of carbonized and cremated archaeological bones, as well as those exposed to unknown thermal conditions together with experiments in modern bones, are recommended.  相似文献   
50.
清代是我国古陶瓷生产最辉煌的时期,烧造的瓷器品种繁多,各类颜色釉的制作水平达到了历史高峰。清代的红釉(彩)名称更是多达几十种,如“矾红”、“抹红”、“珊瑚红”、“红彩”、“钧红”、“均红”、“鲜红”、“郎窑红”、“牛血红”、“霁红”、“宝石红”、“豇豆红”、“釉里红”、“胭脂红”、“胭脂水”、“粉红”等。为弄清各种称谓红釉(彩)的主要呈色元素及其影响作用,本工作采用无损的X射线能谱分析(EDXRF)技术对清代瓷器的红釉(彩)进行系统测试,获得了各种红釉(彩)呈色元素定性及半定量数据。分析结果表明,清代红釉彩可以依据呈色元素划分为四类,即低温铁红彩(Fe)、高温铜红釉(Cu)、低温金红彩(Au)和朱砂红彩(HgS),并且各元素含量的改变会影响红釉(彩)呈色。  相似文献   
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