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21.
为研究出土墓葬青铜器铸造地,利用X射线荧光光谱法对湖北襄樊的余岗、沈岗、团山、陈坡四处墓地出土的部分青铜器泥芯、陶片进行测试分析,试验结果与山西侯马、武汉盘龙城遗址进行比较分析。对比研究显示,襄樊地区泥芯与当地墓土、陶片在常量元素上具有高度一致性,而与黄河流域的侯马和长江中下游的盘龙城有明显区别,说明襄樊地区这部分铜器应为本地铸造,暗示江汉流域存在自己特有文化。本项研究工作首次尝试利用同墓葬陶器化学成分探索青铜器铸造地,是泥芯研究青铜器铸造地的重要补充,泥芯和陶器相互配合,为青铜器铸造地研究提供了一种新思路。  相似文献   
22.
A dated (1773) openwork basket labelled “PHILADELFIA” attributed to the Bonnin and Morris factory has a lead-bearing, silicious–aluminous–calcic (S-A-C) composition that contrasts with the phosphatic (bone ash) porcelains known to have previously been made during the mid-1760s to early 1770s in what is now the United States. The basket was underfired and so contains relics of a flint (Pb) glass flux, but kiln temperatures were nonetheless sufficient for subsolidus pseudowollastonite and anorthite to have been resorbed, implying that the duration of firing (soaking) near peak kiln temperatures was insufficient to ensure thorough vitrification. During cooling, liquidus pseudowollastonite and silica polymorphs (but not anorthite) formed, showing that the melt was confined to the tridymite–pseudowollastonite cotectic above the Trd–Wol–An eutectic (1170 °C) in the SiO2–Al2O3–CaO system. Rapid cooling is also indicated by quenched silica polymorphs in the relict glass particles. Although Bonnin and Morris employed some former Bow (London, c. 1743–74) workers, the S-A-C wares initially produced by this factory are compositionally distinct from the 1773 basket, which in this regard more closely resembles the body and glaze of a reputed Chelsea triangle-period (London, c. 1745–49) vessel. Regardless of how they obtained this technology, it is ironic that Bonnin and Morris chose to abandon phosphatic pastes in favour of what in Britain had become an obsolete formula.  相似文献   
23.
Archaeological surface finds are difficult to date. There are several useful methods, but each requires special circumstances and has one drawback or another. On the west coast of South Africa marine shell are abundant on surface sites but they are rarely dated because they are perceived to be in disturbed context and in questionable association with artefacts. This paper attempts to rectify this misconception and shows that, although far from perfect, a large suite of surface dates can shed as much light as excavated data. On the Vredenburg Peninsula they help refute the hypothesis that two economically and culturally distinct populations shared this pre-colonial landscape since 2000 BP.  相似文献   
24.
The early medieval period marks an important turning point in the history of glassmaking, since it comprises the transition period between the mineral-based silica-soda-lime glass of the Roman tradition and the plant ash-based glass. With the aim of expanding the knowledge on the glass recipes and technologies of this period, 37 glass samples were analyzed, originating from the archaeological excavations of San Genesio (Tuscany) and dated from the fourth to the eleventh century. The major and minor element concentrations were measured with SEM-EDX, while the trace elements were quantified with LA-ICP-MS. The results were compared with published compositions of glass samples of similar age in order to highlight differences and similarities. The results offer a very interesting view on the glass circulation in the religious/residential/manufacturing center of San Genesio in the early medieval period. Most of the glass has a typical late-Roman composition, but some glass fragments are identified as soda ash glass. These are among the earliest medieval ash-fluxed glasses ever found in the Italian peninsula.  相似文献   
25.
安徽南陵出土部分青铜器研究   总被引:1,自引:1,他引:0  
安徽省南陵县是长江下游地区最早而且规模最大的冶炼中心之一,其古代矿冶遗址可上溯至西周晚期。本研究对南陵出土的不同年代和类别的青铜器样品进行了金相检测及合金成分定量分析。结果表明,只有容器存在铜铅二元合金和铜锡铅三元合金,但是热锻淬火的容器却不含铅,含锡量恰好位于适合该工艺操作并具有良好性能的区间。兵器、工具、车马饰均为铜锡二元合金,说明当时的工匠对于合金成分配比与性能的关系有明确的认识。越式鼎腹部样品具有热锻淬火马氏体组织,同样的金属结构还见于汉代铜锣等乐器、峡江地区战国中晚期青铜剑、江都大桥镇南朝青铜器窖藏出土的多件青铜容器,而镇江地区出土吴国青铜戈则具有铸造淬火组织,工艺稍有差别。这些器物中发现高锡青铜淬火组织不是偶然的,高锡青铜热锻淬火技术至少可以上溯至春秋战国时期,用以改善高锡青铜的机械性能。  相似文献   
26.
This article explores the dissipation and dispersion of torsional wave resulting from imperfection in elasticity in terms of internal friction, layer width between dissimilar homogeneous viscoelastic isotropic medium having Voigt-type viscosity. The closed forms solutions for the displacement in the upper layer and lower half space are obtained separately. The generalized torsional wave period equation is obtained and the angular frequency has been plotted against wave number for different values of relevant parametric variation and certain particular cases have been deduced. Dissipation and dispersion are analysed using two and three dimensional plots along with filled contour plots.  相似文献   
27.
金沙遗址博物馆大气污染特征研究   总被引:1,自引:0,他引:1  
为全面了解金沙遗址博物馆遗址区空气污染特征及污染物来源,在2019年秋季对遗址保护厅内外大气中细颗粒物(PM2.5)和挥发性有机物(VOCs)进行了观测,并对各自化学组分进行了全面分析。结果发现:金沙遗址博物馆遗址保护厅内外PM2.5污染严重,平均质量浓度分别为77.0μg/m3和94.6μg/m3;受人为影响程度的不同,室内昼夜差异明显强于室外。室外的OM、NO3-和SO42-浓度高于室内,而室内的NH+4和典型的地壳元素(K+、Mg2+和Ca2+)浓度高于室外;受化学组成的影响,室内外PM2.5分别呈碱性和酸性。地壳元素在整体元素中占据绝对主导,室内外占比分别可达82.8%和84.4%。通过富集因子分析得知Cu(室外)、Ag、Cd、Sb元素均达到了重度富集。室内外VOCs浓度几乎相同,分别为81.2×10-9和81.3×10-9,其中烷烃的贡献比例最高,分别为44%和46%;源自机动车、工业溶剂涂料使用、燃油挥发及生物质燃烧等人为源的VOCs物质在室外的浓度要明显高于室内。这些研究结果对于金沙遗址博物馆遗址区空气质量的全面了解、土遗址及其中文物的高质量保存和提供优质的参观环境具有重要意义。  相似文献   
28.
While surface collection constitutes an important component of field research at the site and regional levels, the association between surface and sub-surface materials needs to be examined through independent lines of evidence. This study employed manual bucket auger probing and soil geochemistry at the Formative site of Tlalancaleca, Central Mexico (800 b.c.a.d. 250), to evaluate the results of surface collection and to understand the formation process of the anthropogenic landscape. The combined results at one of the largest architectural complexes at Tlalancaleca indicate that it was built during the Late Formative period (500–100 b.c.) and rebuilt during the subsequent Terminal Formative period (100 b.c.a.d. 250), which is corroborated by radiocarbon dates. Moreover, the results suggest segregated uses of space such as cooking/storage, waste disposal, and craft production areas within the complex. Overall results demonstrate the effectiveness of this multi-method approach for reconstructing occupational history and activity areas.  相似文献   
29.
As the only type of instrument capable of determining artifact geochemistry in a wide variety of settings, portable X-Ray Fluorescence (PXRF) may be frequently utilized as probably the best option for collecting data when removal of objects in part or in whole is unfeasible. However, using PXRF in circumstances where sample selection and preparation diverge from standards developed for lab-based instrumentation requires assessing the impact of new and potentially limiting factors to establish the validity of the method in these new contexts. Here we examine the effects of surface contamination and chemical weathering on the ability to assess provenance of igneous building stones used in the Cuzco region of Peru. Surface contamination was assessed through comparing low-impact cleaning methods on diorite and andesite blocks, and weathering was examined by comparing weathered vs. fresh surfaces of samples from two andesite quarries. In general, the lightest elements were most impacted by contamination and weathering while measurements of many of the heavier elements commonly used in provenance studies were relatively unaffected. Concentrations of Pb and Zn were problematic in the urban context of Cuzco because of pollution. Ability to determine provenance of building stones within those limitations (i.e., the validity of this application of PXRF) was demonstrated in a preliminary study by comparing measurements from uncleaned, exposed building stones in the region to fresh quarry samples.  相似文献   
30.
根据表面着色的化学动力学原理论证了铜及铜合金表面人工仿古着色处理的某些必要过程。如为何要进行着色前的表面预处理;表面预处理的主要内容及着色反应的化学机理。并对目前众多的人工表面着色配方进行了归纳。  相似文献   
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