琼脂凝胶在青铜文物激光清洗中的应用研究

激光清洗应用于青铜文物上有时会使其表面颜色及其他一些物化性质发生改变。如何优化这种方法改善这种状况?为此,本工作将琼脂凝胶-激光联用作为一种可能的优化手段,首先研究了凝胶对激光能量和作用的影响,包括以能量计测量激光穿过凝胶层后的能量减弱幅度,以及通过热敏纸和文物样品上的烧蚀斑观察凝胶对激光烧蚀结果的影响。其次在不同类型的青铜文物样品上将之与普通湿法激光清洗、机械清洗等手段做清洗效果的对比实验,并以视频显微镜、扫描电镜及能谱仪、X射线衍射等手段进行分析验证。实验结果发现,凝胶能小幅度降低激光能量,减轻激光引起的青铜文物表面微观结构的改变,为清洗操作提供更灵活多样的选择。凝胶-激光联用的方法在实验的文物样品上取得了理想的清洗效果,兼顾了操作的效率性和安全性,是在今后的应用中可被考虑的手段。     

非损伤分析法测试黄冶唐三彩之特性

一、前言 承蒙中国河南省文物考古研究所提供的黄冶窑三彩标本,我们尝试用非损伤分析的方法对其进行了测试研究.其间我们做了显微镜细微观测、光谱反射率测定、釉药成分的定量分析、胎土及釉药的X光谱分析等方面的工作,将其与已经发表过的唐代和日本等地的文献资料和出土资料进行了比较研究.     

广元千佛崖莲花洞彩绘颜料拉曼光谱分析

为了解广元千佛崖莲花洞造像的制作工艺与彩绘颜料成分,利用体视显微分析、金相显微分析、激光拉曼光谱分析技术对其进行物相和成分分析。分析结果表明,莲花洞造像彩绘直接绘制在岩石雕像表面,无底层。彩绘颜料分为多层,最多有三层,说明历史上至少有两次重绘。红色颜料为赤铁矿、朱砂;蓝色颜料主要为青金石与石青;绿色颜料为石绿、碱式氯化铜;白色颜料为硫酸铅。同时也表明,拉曼光谱分析彩绘颜料成分组成简便、快速、对样品要求量小,对样品无损分析,符合文物材质分析的要求,并可得到准确的信息。造像彩绘制作材料及工艺的分析结果为莲花洞造像彩绘保护研究提供了科学依据。     

故宫南大库出土黑地珐琅彩瓷的科学分析和工艺研究

2014年故宫南大库考古遗址出土了一件被认为是瓷胎画珐琅的雍正黑地彩瓷残件,本文采用光学显微镜、X射线荧光光谱分析、显微拉曼和激光诱导击穿光谱(LIBS)等无损分析方法对该件彩瓷进行了分析。结果显示,通过LIBS测定的彩瓷表面的黑色彩料中含硼,符合前人研究中测试的珐琅料的化学组成特征;黑色彩料中的着色元素包括钴、铁和锰,黄色彩料含有的着色元素为锑和锡,红色彩料由金着色,绿色彩料由铜着色。本件珐琅彩瓷可能采用了受西方工艺影响的珐琅料与中国传统低温釉彩相结合的工艺。     

山东临淄山王村俑坑出土陶质彩绘颜料初步分析

2008年5月山东临淄山王村俑坑出土了数量较多的彩绘陶质文物,为了了解彩绘颜料结构和成分,采用粉末偏光显微法、剖面观察结合拉曼光谱分析对彩绘文物表面颜料样品进行分析。结果表明,这批陶质文物表面彩绘是以白灰做地仗层,由碳酸钙、白土、铁黑（Fe₃O₄）、铁红（Fe₂O₃）、朱砂等颜料调和而成,且厚度不均。在个别样品中发现了少量的中国蓝颗粒(BaCuSi₄O₁₀),这是这次分析中较为重要的发现,此分析结果也可为考古研究提供科学信息。     

饱水木质文物的风冷干燥脱水研究

许多出土饱水木质文物因其降解严重、含水率较高,容易在脱水过程中出现不可逆的收缩变形以及开裂现象,从而遭到严重破坏。因此,饱水木质文物脱水方法的研究是文物保护工作中的重要课题。为探究风冷冷冻法对饱水木质文物脱水的效果,以一批无法复原的出土饱水木质文物为研究对象,在对其材种、含水率、基本密度及化学成分进行了测定和分析后,使用一台风冷电冰箱在-18℃条件下对样品进行了风冷干燥脱水处理,记录脱水时间和脱水效果,并分析了该方法的传质传热特点,证明了风冷干燥法用于饱水木质文物的脱水干燥能够取得良好效果,并且具有对文物干预小、适用性广、操作简便、成本低廉等优点,为饱水木质文物的脱水处理提供了一种新的思路。     

偏光显微法在颜料研究中的发展现状与趋势

对偏光显微法在颜料分析研究中国内外的发展概况和发展趋势进行了论述,并对偏光显微法和拉曼光谱分析的结合进行了探讨.对该方法在文物研究中的地位给予了较高的评价.     

拉曼光谱在纸质文物研究中的应用

纸张的老化程度一直是纸质文物保护中的重要研究方面,以往多采用目测法和经验来推断纸张的老化程度。纸张物理强度、聚合度等能表征老化状态的理化性能测试由于需要大量的样品而无法用于文物检测。近年来随着显微共聚焦拉曼光谱、近红外傅里叶变换拉曼光谱、表面增强拉曼光谱等技术的发展,作为一种原位、无损、微区的分析方法,拉曼光谱被越来越多地应用到了纸质文物的相关分析研究中,为纸质文物的保护修复提供科学依据。结合国内外文献,对拉曼光谱在纸张老化、碳黑颜料以及其他颜料上的应用和研究现状进行了梳理归纳。随着拉曼光谱应用的不断深入,以及与其他分析技术、化学计量学等的结合,未来将在纸质文物研究中发挥更多的作用。     

白银文物主微量元素测试的数据质量与分析条件研究

本文利用古代白银成分标准参考物质,对五种不同方法获得的白银主微量成分数据的准确性进行评测,并对其在实际白银文物样品分析中的适用性进行了研究。结果显示,激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)对白银文物的Ag、Cu、Pb、Au、Bi、Sn等主微量元素均可得到相对准确的结果,适用于白银文物研究中各类不同含量元素的分析需求。基于标准物质建立的扫描电镜能谱(SEM-EDS)φ基体校正模式可以对白银文物中的主量元素(>1%)进行准确分析。便携荧光(pXRF)数据的使用需要考察样品表面锈蚀和污染情况、样品中的合金元素含量以及分析面的形状和大小。当文物中的Cu含量低于5%,且被测试样品具有能够完全覆盖分析窗口的平整表面时,pXRF的分析数据具有半定量意义。     

五种移动式拉曼仪器在文物分析上的比较研究

考古中主要目的之一是从一件文物上无损地提取相关信息。随着最近移动式仪器在线分析上的发展,拉曼光谱分析在这一研究领域中得到了运用。纤维光学拉曼仪器已被应用于贵重文物的直接分析中。而且有研究表明移动式仪器可用于文物的现场检测。     

Analysis of rock samples collected from rock hewn churches of Lalibela,Ethiopia using laser-induced breakdown spectroscopy

With the aim to study alteration processes of the rock hewn churches from Lalibela (Ethiopia), we applied Laser Induced Breakdown Spectroscopy (LIBS) technique to measure the elemental composition both of the bulk rock materials and their external layers, exposed to the environmental factors. The analytical plasma was generated by nanosecond pulses of an Nd: YAG laser emitting at 1064 nm. Different major and minor sample constituents were detected, including Ca, Mg, Na, Fe, Ti, Al and K. The detected O emission originates both from air surrounding and the sample, while the intensity of N lines, coming exclusively from air, was used for the LIBS signal normalization. By depth profiling of the weathered basalt rock, we observed a lower presence of K in the external layers, corresponding to the first 5 laser shots. The emission from this element is anti-correlated with the line intensities from O, and this was attributed to the variations in relative abundances of clay minerals and K-feldspar. The analogue measurements were performed on the tuff rock, and compared to the spectra from powder samples containing only the external soft material, scratched from the rocks. These analyses show an abundance of H in the weathered, wetted layers and suggest that cations are lost from the constituent primary minerals and replaced by H⁺; this process disrupts the lattice structure and causes a marked loss of strength. The studies presented here demonstrate that LIBS is a useful technique for studying the alteration processes in the rocks, caused by environmental factors.     

Characterization of Iron age pottery from eastern Turkey by laser- induced breakdown spectroscopy (LIBS)

Selected pottery sherds coming from the Ayanis, Dilkaya and Karagündüz excavations in eastern Turkey and dated from the Early to Middle Iron Age were examined as regards their composition by using laser-induced breakdown spectroscopy (LIBS). The objective of the study was first to investigate the potential of the LIBS technique in the compositional analysis of pottery and further to explore correlations in spectral data, by using chemometrics methods that would possibly enable discrimination among different sherds. This work is part of a broader study aiming to examine clay variability both before and during the Urartian State period and to explore possible relationships and differences among pottery objects from fortresses and settlements or settlements and cemeteries on the basis of the clay composition of sherds. Preliminary results demonstrate that by using the LIBS technique it is possible to analyse pottery sherds in qualitative and semi-quantitative ways, providing information on the clay and slip composition. Furthermore, encouraging results have been obtained by carrying out principal component analysis (PCA) on the LIBS spectra, which suggest that in certain cases, it is possible to directly correlate spectral information with the origin of pottery sherds.     

EVALUATION OF THE ANALYTICAL POTENTIAL OF LASER‐INDUCED BREAKDOWN SPECTROMETRY (LIBS) FOR THE ANALYSIS OF HISTORICAL GLASSES*

The novel and—for archaeometrical applications—still rarely used Laser‐Induced Breakdown Spectrometry (LIBS) was tested on various standard glasses for its spectrometric performance. LIBS is an almost non‐destructive method based on the time‐resolved detection of optical emission following direct laser ablation. A frequency‐quadrupoled Nd:YAG laser at 266 nm was found to cause a hardly visible crater of c. 200 µm in diameter. The application of an innovative high‐resolution Echelle spectrograph allows the fast and simultaneous determination of up to 90 elements in the spectral range from 200 to 780 nm, with a resolution of 10–30 pm under ambient conditions. In principle, LIBS has a high analytical potential for archaeometry; in particular, for the determination of light elements (Li, Be, B and others). Because the measurement parameters (laser energy, delay time and number of pulses) do not independently influence the emission signal, their optimization proved to be complex and is rather a compromise for the range of elements. The effects of sample distance, surface roughness and the accumulation of depth profiles were studied. Problems arose for the determination of sodium and potassium in higher contents due to self‐absorption effects. Quantification tests using a silicon line as internal standard yielded a precision range between 3% and 20% relative, but in general no satisfying accuracy for a number of elements. However, these problems might be overcome in the near future by improved spectrometer set‐ups and matrix correction approaches.     

The Study of Archaeological Floors: Methodological Proposal for the Analysis of Anthropogenic Residues by Spot Tests,ICP-OES,and GC-MS

The identification of chemical activity residues on archaeological surfaces requires the analysis of large numbers of samples, which can be costly and time consuming. Researchers wishing to apply sediment chemistry often are confronted with a dilemma of which technique to use and how to accommodate sediment chemistry into their budget. We propose an approach to the identification of chemical activity residues in which semiquantitative spot tests, which are cheap, quick, and easy to apply, are employed as an initial phase of analysis in order to leverage the results of more time-consuming and costly instrumental techniques. Three examples that pair spot tests with gas chromatography-mass spectroscopy and inductively coupled plasma-optical emission spectrometry analysis show that spot tests successfully identify areas of interest. This approach can save both time and research funds.     

Pigment analysis in Bronze Age Aegean and Eastern Mediterranean painted plaster by laser-induced breakdown spectroscopy (LIBS)

Laser-Induced Breakdown Spectroscopy (LIBS) was used in the examination of Bronze Age painted plaster samples from several sites in the Aegean and Eastern Mediterranean. The elemental content of paint materials was determined in most cases leading to the identification of the pigment used in agreement with data from analyses of the same samples with other established techniques. The analyses demonstrate that a virtually non-destructive technique such as LIBS provides sufficient data for the elemental characterisation of painting materials while in parallel has the capability for routine, rapid analysis of archaeological objects enabling the quick characterisation or screening of different types of artefacts. This certainly shows an important way forward in technological studies of fragile and scarce archaeological material.     

便携式X射线荧光现场分析壁画颜料适用性研究——以西藏拉萨大昭寺壁画为例

便携式X射线荧光光谱仪作为快捷的无损分析技术,广泛应用于壁画文物的现场分析中.本文利用便携式X射线荧光光谱仪分析了西藏拉萨大昭寺转经廊壁画,选取部分样品,利用实验室X射线荧光分析,发现所分析颜料的主要显色元素具有一致性,并利用拉曼光谱确定了壁画颜料的成分.通过比较研究,发现便携式X射线荧光光谱仪可确定大部分色彩较为纯正的颜料的成分,同时,由于西藏拉萨大昭寺壁画颜料的杂多性,对于含砷的橙色颜料、含砷或含铅与含铁的黄色颜料、含铜砷的绿色颜料、含钙硫的白色颜料、群青与孔雀石的混合颜料则需结合拉曼光谱确定之.本研究工作显示,利用便携式X射线荧光光谱仪开展现场检测,可极大地减少实验室分析样品的取样数量,有利于壁画颜料的无损分析与微损分析.     

Re-examining the chemical evaluation of diagenesis in human bone apatite

Isotopic analysis of human bone is becoming an increasingly important tool for the archaeologist in divining past life-ways. The isotopic ratios within bone are often assumed to be preserved as in life, but diagenetic change can alter the ratios, invalidating the results of isotopic analysis. Diagenesis can be evaluated in a number of ways, but most often spectroscopic techniques are utilised as the most efficient and easiest to understand methods for the archaeologist. Many isotopic studies do not report the possibility of diagenetic change, and if it is reported it has often been quantified using a single method of chemical analysis, FTIR spectroscopy. This study set out to test the value of FTIR analysis using human remains from the prehistoric site of Ban Non Wat, Northeast Thailand, and to compare the results with the non-destructive technique of FT-Raman spectroscopy. The study shows that FTIR spectroscopic analysis gives far less detail on the condition of bone than Raman spectroscopy, which does not merely indicate recrystallisation has occurred, but also shows clearly whether or not collagen is present, allows identification of ionic substitions which have occurred and identification of secondary minerals which have formed. Raman spectroscopy, combined with LA-ICP-MS analysis also revealed that soil composition and groundwater flow are the conditions which most affect diagenesis at Ban Non Wat.     

SYNCHROTRON FTIR MICRO‐SPECTROSCOPY APPLIED TO THE STUDY OF POLISHED SERPENTINITE ARTEFACTS: A NON‐DESTRUCTIVE ANALYTICAL APPROACH

In prehistory, serpentinite was one of the most frequently used raw materials to produce polished stone artefacts. Several conventional analytical techniques can be applied to identify the serpentine minerals, but their application generally requires a powdered sample. This implies that the artefacts to be analysed must be damaged, and the possibility of analysing a mixture of different serpentine polytypes is high. The use of spatially resolved techniques is therefore a necessity to overcome this problem. Several thin sections of serpentinitic rocks and prehistoric axes have been analysed by synchrotron radiation Fourier transform infrared micro‐spectroscopy. The spectra were acquired directly on specific points of polished stone artefacts and this allowed the recognition of the different polytypes of serpentine minerals without causing any damage to the objects. The results show the infrared micro‐spectroscopy technique to be a useful tool for the characterization of archaeological lithic material.