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41.
利用微聚焦能量色散X射线荧光光谱仪(EDXRF)、拉曼光谱仪(RS)、X射线电子能谱仪(XPS)等无损分析法,对重庆忠县翠屏山崖墓出土金银器的基体成分、表面腐蚀物成分以及其物相结构进行了系统的分析测试。结果表明:两个金器样品的含金量均高达90%,纯度较高。此外,还含有一定含量的银、铜、锌、镍、铷等杂质元素;银器中,大多数样品含银量高达97.38~98.85%,同时还含有少量硫、铬、镍、锌、金等杂质元素;银器表面附着的黑色的腐蚀物,经鉴定为Ag2S,红褐色腐蚀物的物相结构为Cu2O;值得关注的是,有一个银器样品含银95.2%,含铜3.19%,应为铜银合金,此结果对于探讨我国古代银铜合金技术发展与演变的研究,具有非常重要的意义。  相似文献   
42.
A combination of Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD) and portable X-ray fluorescence spectroscopy (PXRF) was used on the clay fraction of Ertebølle ceramics from several Late Mesolithic sites in Scania, southern Sweden. The aim was to provide up-to-date information about clay types used during that period within the Scanian Ertebølle cultural unit, and to elucidate social aspects relevant to the organization of pottery production and the role of ceramics in the local societies. The results suggest similar clay preferences across the sites, site-based pottery production using local clays and zero mobility of ceramics between the sites. The chemical separation of the ceramics from the site of Soldattorpet into two compositional groups suggests possible multigroup occupation. The origins of aromatic hydrocarbons, extracted previously from the ceramic matrix of the vessels during a lipid residue study, were also investigated, and a discussion is provided.  相似文献   
43.
This paper considers the epistemic career of visual media in ethology in the mid-20th century. Above all, ethologists claimed close contact with research animals and drew scientific evidence from these human-animal communities, particularly in public relations. However, if we look into the toolboxes of comparative behavioral biologists, it becomes evident that scientifically valid research results were primarily obtained by experimenting with model images. These visual specimens tell a technical story of the methodological requirements in behavioral science necessary to bridge everyday observations between the laboratory and the field. By neutralizing individual traces of animal bodies as well as their observers, they prompted the abstraction of ethological hypotheses. The case study of East-German biologist Günter Tembrock (1918–2011), who maintained his own collection of newspaper clippings, drawings, photographs, and films, offers a new perspective on the methodological development of this field. Furthermore, this article contributes to a scholarly discussion geared toward expanding the spaces of ethological research. My analysis of the image collections of the Forschungsstätte für Tierpsychologie presents the archive as a relevant site of study in the history of ethology.  相似文献   
44.
此研究是以石材和土壤所构成的考古遗址为主要研究对象。在确定石材和土壤的渗透性下,通过数字体积相关法(DVC)和数字图像相关法(DIC)对干湿劣化的环境条件进行定量的评估,并提出控制这种劣化发生的环境调整方法。 为了收集基本数据,通过DIC及X射线成像技术分析从湿润到干燥的过程中丰浦硅砂的位移量实验,并在实验中,使用DIC计算样品在收缩应力下的变形分布。此外,本次实验以铁粉作为示踪剂添加至样品中,并以铁粉作为参考点计算丰浦硅砂特定范围的移动量,借此评估铁粉作为示踪剂的适用性及精确性。结果表明,通过拍摄干燥前后样品的X射线图像,并用DIC进行分析可以计算出干燥前后的变形分布。在样品中添加示踪剂也被发现有助于分析样品局部区域的移动方向及移动量。因此通过此基本数据的检验,相信将来通过X射线计算机断层扫描(X-CT)及数字体积相关法(DVC)的应用,可以用来阐明反复干湿风化的劣化机制。  相似文献   
45.
Beyond the material forms that constitute public space, it is subject to representations or images that shape the types of use, forms of appropriation, and general perception that people have of it. Following a centre‐periphery gradient that allows us to compare three zones of the Montreal region (pericentral, periurban, and the northern ring), we analyzed photographs available within cyberspace (from different municipalities and boroughs, local newspapers, and social media) to draw out representations of public space. What can photographs available online tell us about how space is perceived? We have established a typology of images of public space (idyllic nature, urban scene, festive space, empty space, family portrait) that are representative of the overall corpus studied. We have compared these results with a correspondence analysis to clarify the structure of interaction between the variables. The analysis demonstrates that the representations are more differentiated between neighbourhoods than between regions, and that while newspapers and municipalities represent more themes of sociability and family life, social media shows more empty spaces, whether they be monumental spaces, or spaces of daily life.  相似文献   
46.
Abstract

LiDAR datasets, from which high-resolution topographic maps can be generated, are becoming commonplace in archaeological analyses. Like any remote sensing technique, LiDAR records only a limited range of phenomena and the data are a snapshot of ground conditions at the time of collection. The temporally specific nature of LiDAR is problematic at sites with postdepositional destruction. This paper presents a method for identifying and recovering lost landscapes by combining LiDAR, archival aerial photographs, historical observations, and fieldwork. This method was developed to reconstruct the topography of ancient shell mounds constructed by hunter-gatherers on the St. Johns River in northeastern Florida (ca. 7500–500 cal b.p.) and altered by modern land use. The reconstructions demonstrate the influence of ancient communities on modern landscapes and can be used as a basis for further analyses of hunter-gatherer land use, social interaction, and cosmology.  相似文献   
47.
The possibility of determining the human or animal origin of bones from the lattice parameters of their inorganic bioapatite phase, when subjected to a high temperature treatment using the powder X-ray diffraction (XRD) technique, has been explored on a wide number of specimens. Forty-two animal bones were treated in a furnace at 1100 °C for 36 min and compared to 53 cremated human bones from a range of ancient necropolises. The X-ray diffraction patterns of bioapatite were simulated using both monoclinic P21/b and hexagonal P63/m structures to verify any occurrence of phase transformation and any difference in the lattice parameters due to the model. It was determined that the differences between the a-axis and c-axis of the monoclinic and hexagonal lattice were unimportant. Some outlying values were revealed to be caused by the presence of chlorine ions diffused into the apatite structure increasing its average unit cell values. Nevertheless, our results clearly show that in terms of lattice parameters the variability of human specimens are completely overlapped by the non-human variability making the use of XRD in order to distinguish animal from human bones questionable.  相似文献   
48.
We have used synchrotron-based X-ray fluorescence imaging (XRFI) to examine sherds of painted ceramics from prehistoric cultures of the American Southwest. These sherds are very well suited to XRFI analysis. Paints can generally be detected and distinguished by the fluorescence intensities of their constituent elements. Spatial maps of element distributions yield the spatial distribution of pigments. Pigments can be distinguished that are (or have become) visually similar; layers that have been obscured by overpainting can be examined; and pigment residues can be distinguished from surface contaminants deposited after painting and firing. As a result, XRFI allows the painted motifs to be clarified and hidden features to be revealed. Furthermore, the very rapid scanning and high sensitivity elemental detection possible with synchrotron-based XRFI facilitate measurements on large collections of sherds, allowing an integrative rather than anecdotal analysis.  相似文献   
49.
An archaeometric study was carried out on 40 gold leaf tesserae from mosaics in Italy dated 1st to the 9th century AD. Glass layers and gold leaf were both analysed by X-ray microanalysis. The main aim was the identification of the composition of the glass and of the gold leaf, in order to assess the variations in composition and nature of the tesserae in the examined period.  相似文献   
50.
石质文物本体在长期自然风化作用下形成粉化和裂隙等病害,其存在将导致石质雕刻品各部分密度的差异,而泥质镶嵌和包裹引起的材质改变及雕刻品厚度的变化,都将影响X射线的吸收效果。当X射线穿透石质雕刻品时,置于其背面的照相胶片上,将记录由透射X射线产生的潜像,经扫描仪处理,使之转变为显著灰度差的影像,据此分析石质雕刻品金箔包裹的本体病害情况和保存状态。为此,用此技术对重庆大足千手观音进行历时一个多月的X探伤调查。结果显示,千手观音石质雕刻品的金箔包裹本体存在不同程度的风化和裂隙,而其历史上泥质修补及补接状况,也一目了然,从而弥补了传统病害调查的不足。本项调查为大足千手观音的修复保护提供了重要的依据,也可为千手观音的修复史研究提供有价值的信息。  相似文献   
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