实验室模拟硅酸盐质文物除盐控盐的可视化研究

针对目前广泛使用的材料吸附除盐和加湿喷雾控盐等方法对含盐硅酸盐质文物可能造成的损伤,采用扫描电子显微镜、电阻仪和高分辨摄影仪等实时在线记录具有显色性质硫酸铜溶液在吸附除盐和水雾控盐加湿干燥过程中文物内部盐带分布的变化。研究结果表明：吸附材料除盐法和表面喷雾控盐法均会加速样品内部盐离子的扩散迁移,在样品中形成双层或多层盐结晶带;所形成的盐结晶带与样品结构特性、盐溶液在样品中的运移和蒸发速率、加湿-干燥频率等因素有关,其中溶液毛细上升高度和样品透气性越好,以及环境温度和盐溶液浓度越高,加湿-干燥频率越快,样品内部的盐带分布变化越明显。材料吸附除盐和水雾控盐等方法加速了盐溶液在样品内部的扩散,促进多层盐带的形成。这些结果对于目前文物保护所采取的除盐控盐技术手段提出了新的挑战。     

魏家庄遗址出土铁质文物的脱盐处理研究

山东济南魏家庄遗址出土铁质文物中含有大量有害氯离子,严重威胁着文物的安全。因此,脱盐就成为该批铁器保护的重点,是阻止铁器继续腐蚀的重要保证。在经一系列实验工作后,该批铁器的脱盐溶液采用0.005mol/L NaOH溶液,对于仅为铁质的容器类铁器采用直接浸泡法,同时结合冷热交替和超声波法;对于带有鞘的兵器类铁器采用2%Primal AC33加固后再进行脱盐;对于带有漆皮痕迹的铁器也试用了纸浆脱盐法。铁器经脱盐后氯离子含量大大降低,脱盐取得了很好的效果。     

MAGNETIC SUSCEPTIBILITY USED IN NON-DESTRUCTIVE PROVENANCING OF ROMAN GRANITE COLUMNS

Magnetic susceptibility provides a rapid, cheap and non-destructive method of in situ characterization of archaeological artefacts containing magnetic minerals, and can be used as an aid to geological provenancing. Three hundred and sixty-three Roman granite columns were measured by this method and results show clear groupings and similarities with potential granite sources in Italy, Turkey and Egypt. Magnetic susceptibility measurements must be made on representative, unweathered surfaces of rocks and artefacts, and corrected for object size and surface relief according to manufacturers’recommendations. In addition, corrections for column curvature have been derived for use with measurements made on columns.     

铁器文物脱盐清洗溶液中硅酸盐缓蚀性能的研究

硅酸盐是一种环保型的缓蚀剂,研究水溶液中硅酸盐与铁表面氧化物的相互作用对铁器文物脱盐清洗液的实际应用有较大的指导意义。本工作研究了羟基氧化铁对硅酸盐的吸附作用以及多种因素对Fe/FeOOH/Na_2SiO_3体系电化学行为的影响,并运用XRD技术分析研究了硅酸盐水溶液处理对钢铁表面氧化物形态的影响。结果表明,在Fe/FEOOH/Na_2SiO_3体系中,硅酸盐吸附在钢铁表面羟基氧化物上,反应生成了新的物质,形成了较为致密的缓蚀膜,可同时抑制钢铁的阴、阳极反应,且对阴极反应的抑制作用较强。     

The Removal of Protein from Mineral Surfaces: Implications for Residue Analysis of Archaeological Materials

Although there has been great interest and controversy concerning the detection of proteins in archaeological residues, very few studies have considered the effect of different extraction methods. Using well-defined control materials, this study compares the extraction efficiency of a number of different extraction reagents. Immunological and spectrophotometric assays are used to assess the amount of protein removed by each extraction method and the effectiveness is reported with reference to previous work. None of the previously reported methods were found to be effective at removing the protein from the mineral surface. We conclude that proteins are very strongly bound to the surface probably via short-range bonds. Although this may be encouraging for the long-term preservation of proteins in this context, extraction methods will have to be re-evaluated in order to achieve efficient recovery.     

典型硫酸盐环境中砖质文物的脱盐与加固材料

中国保存有众多砖质文物建筑,目前这些文物多处于户外环境中,面临严重盐害导致的掏蚀损毁问题。因而,研究兼具脱盐功能的加固材料成为砖质文物等保护的一种创新思路,加固材料的研制和工艺技术的开发是其重点和难点,具有重大的社会需求和急迫性。为此,本工作从可溶性盐的破坏机制出发,研究出一种双组分无机加固材料,加固方法是Ba(OH)_2甲醇溶液与H_2C_2O_4、H_3PO_4乙醇溶液交替滴加,并模拟可溶性盐(NaCl、KCl、Na_2SO_4)分布的典型环境,进行加固、除盐,借助X射线衍射仪(XRD)、X射线荧光光谱仪(XRF)和无线阻尼抗钻仪等现代科学仪器,追踪盐的流出与转化过程。结果表明,本材料不仅能够加固模拟样品,同时能对最具破坏性的盐Na_2SO_4实现不可逆转化,生成重晶石的主要成分BaSO_4,加固与脱盐一次完成,是一种具有实际应用潜力的新材料。     

“南澳Ⅰ号”出水陶瓷器脱盐技术对比研究

为了对“南澳Ⅰ号”明代沉船出水的大量陶瓷类文物进行安全高效的脱盐保护处理,选取“南澳Ⅰ号”出水的3种不同窑系的陶瓷文物作为研究对象,对其胎体理化性能进行分析检测与对比,并在常温静水浸泡、加热静水浸泡、超声波与加热-超声波4种方法11种不同技术参数下分别进行脱盐实验,并作对比研究。研究发现,加热与超声波技术相比常温浸泡法可以大幅度提高脱盐的速率,但是随着温度的继续升高与超声波频率的增加,脱盐速率增加幅度不大。实验中发现超声波对比较脆弱的陶瓷文物的釉面与胎体会产生一定影响。在对比实验基础上提出了3种不同窑系的陶瓷文物相应的最佳脱盐参数,以期为安全高效地完成“南澳Ⅰ号”出水的2万多件陶瓷器的保护脱盐提供研究支持,并为其他沉船陶瓷器保护提供借鉴。     

双通道离子色谱法测定一件陶罐表面结晶盐以及脱盐溶液中的阴阳离子

陶器由于受环境的影响,表面容易出现结晶盐。在保护修复陶器的过程中,脱盐是重要的保护程序之一。本工作主要研究了双通道离子色谱法测定一件陶罐表面结晶盐以及脱盐溶液中的7种阴离子和5种阳离子时,淋洗液浓度、流速对测定结果的影响。实验表明:淋洗液浓度和流速会影响各离子的分离和峰形。当碳酸钠~碳酸氢钠浓度为2.5~1.7mmol/L、流速为0.6m L/min,吡啶二羧酸~硝酸浓度为0.8~1.6mmol/L、流速为0.7m L/min时,各离子峰形好,分离时间适中,分离效果很好。精密度和回收率实验表明,该分析方法的准确度满足定量分析的要求。由此可见,用双通道离子色谱法可以快速、简便、准确地测定结晶盐的离子种类和含量,可以实时监测脱盐溶液中的离子含量能较好地反映器物的脱盐程度。     

The salt chimney effect: delay of thermal evolution of deep hydrocarbon source rocks due to high thermal conductivity of evaporites

Half of the topseals to the world's largest oilfields are evaporites. Rock salt has a thermal conductivity two to four times greater than that of other sedimentary rocks found in oil‐ and gas‐bearing basins. Strong heat conduction through evaporites can increase the geothermal gradient above evaporite deposits, resulting in a positive thermal anomaly and above‐average temperature while simultaneously decreasing the geothermal gradient below evaporites, resulting in a negative thermal anomaly. Most Triassic–Jurassic hydrocarbon source rocks in the Kuqa Basin, western China, are overlain by ~1500‐m‐thick Tertiary evaporites with underlying Cretaceous sandstones and mudstones. Directly measured strata temperatures indicate an obvious break in the steepness of the geothermal gradient above and below Paleogene evaporites, with a significantly steeper geothermal gradient above the evaporites. Simulations of the thermal evolution of source rocks based on data collected from well Kela‐2 indicate that if the thickness of evaporites (mainly rock salt and anhydrite rock) in overlying rocks above source rocks increases compared with the thickness of siliciclastic rocks in the overlying rocks, then strata temperatures and vitrinite reflectance in Jurassic source rocks will decrease accordingly. Our thermal simulations based on the thickness and thermal conductivity of evaporites accurately coincide with previous studies based on homogenization temperatures, hydrocarbon–water contact retrospection, and carbon isotope results from natural gases. The gas generation center located in the Kalasu Tectonic Belt today is also sealed in an evaporite‐related structural trap that formed at this time. Therefore, the speculated natural gas generation times not only correlate with the evaporite‐related structural trap formation, but the calculated maturity of deep source rocks below the evaporites also coincides with current gas reserves. And our studies can help to find the deep oils and gases under thick evaporites.     

Effectiveness of Phosphocitrate as Salt Crystallization Inhibitor in Porous Materials: Case Study of the Roman Mosaic of Orpheus and the Beasts (Perugia,Italy)

Salt crystallization in porous materials constitutes one of the major causes of decay of buildings/archaeological sites in a wide range of environments. Desalination is among the most common methodologies of conservative treatment for salt decay. However, classic desalination techniques might be not suitable for long-term conservation. During the past decade interest has been an increasing towards crystallization inhibitors as a new means of controlling crystallization damage. This study deals with the first in-field application of an environment-friendly inhibitor system— phosphocitrate (PC). In particular, the case study of the Roman mosaic of Orpheus and the Beasts in Perugia (Italy) is presented. The inhibitor is completely soluble in water or alcohol, non-toxic, and easy to apply, thus enabling its use in accordance with the volatile organic compounds emission control and safety during the conservation works. Relevant samples from control and treated mosaic areas were collected and analyzed comparatively by means of Fourier transform-infrared spectroscopy, scanning electron microscopy, and energy dispersive spectrometry to study the potential of the inhibitor system in preventing/controlling salt damage in such archaeological site.     

Phytolith taphonomy: a comparison of dry ashing and acid extraction on the breakdown of conjoined phytoliths formed in Triticum durum

Durum wheat plants grown under optimum irrigation conditions in Jordan were processed in three different ways: 1) using a dry ashing method, 2) using acid extraction and 3) using both these methods, first dry ashing and then acid extraction. The aim was to determine if the laboratory processing method employed has an impact on the number of conjoined phytoliths recovered. This is important because it has been proposed that the number of conjoined phytoliths, or multi cells, can be an indication of water availability in arid and semi-arid regions (Rosen and Weiner 1994). The results showed that the processing method does have an impact on the resulting assemblage, with dry ashing producing a greater number of multi-cells than acid extraction. It is proposed that either the more violent oxidation of organic matter during acid extraction causes the breakup of conjoined phytoliths, or that the silica dehydrates during dry ashing resulting in a slight fusion between the individual phytoliths and hence more conjoined forms.     

Experimental Study on Seismically Resilient Two-Span Bridge Models Designed for Disassembly

Shake-table studies were conducted on a ¼-scale, 2-span bridge model incorporating a newly-developed concept of replaceable plastic hinges and columns that can be easily assembled and disassembled. The plastic hinges incorporate novel materials that mitigate column damage and permanent drift, allowing the bridge to undergo intense seismic shaking and remain operational when most conventional bridges would warrant demolition. Designed to be disassembled, the column components have the potential to be reused, which is intended to help mitigate the environmental impact from material extraction and manufacture. The concept feasibility was demonstrated by assembling, testing, and disassembling the same bridge model twice.     

平遥弓村遗址出土猪骨骨架的现场保护及整体提取

为实施安全、有效的技术保护,采用低浓度Paraloid B-72丙烯酸树脂对出土于平遥弓村遗址,侵蚀严重、强度较低的猪骨骨架进行了现场保护加固处理。在此基础上实施了整体切割,套箱提取,完整的将其提取回实验室。结果表明,使用的方法合理,材料有效。保护工作对今后类似文物的现场保护和整体提取有一定的借鉴作用。     

提升出水瓷器脱盐效率的方法研究

研究了几种在传统浸泡法的基础上提高出水瓷器脱盐效率的方法,电导率测试结果、XRF检测结果以及硝酸银定性分析结果表明,这几种方法均可以在一定程度上提高瓷器脱盐效率,压缩传统浸泡脱盐法所需的时间。     

Non-invasive on-site method for thickness measurement of transparent ceramic glazes based on depth from focus

Glazed ceramics are a common material analyzed through geochemistry, whether in the form of tableware collected during excavations or tiles observed as part of architectural features. Within the framework of these studies, measuring the thickness of the transparent glaze is one of the useful variables available for the characterization of the ceramic, contributing to searches for provenance as well as serialization. However, this task often requires invasive methods performed in the laboratory, which may not always be possible. This paper develops a non-invasive and portable on-site system for measuring the thickness of ceramic glazes. Based on the depth from focus technique, this method makes use of a classical camera, a macroscopic lens, a translation stage, and a laptop for system control. In this article, we test this method through the measurement of glaze for ten samples as compared to results obtained for sections through scanning electron microscopy.     

铁质文物脱盐处理废水中的污染物检测

铁质文物脱盐过程要产生大量废水废水排放不得超过国家或者地方规定的水污染物排放标准。本研究依据国家标准《污水综合排放标准》(GB8978-1996),对腐蚀模拟Z30试片和室外大型铁炮脱盐废水中的污染物含量进行化学分析。结果显示主要是化学耗氧量(COD)、可溶性正磷酸盐、悬浮物等项目超标;分析表明某些过量添加的脱盐试剂和助剂是造成污染物超标的主要原因。一般对馆藏铁器,因脱盐废水量小,可通过清水稀释处理(有时需预处理)后达标排放;对个别室外大型铁器而言,因废水量大,污染物超标严重时,建议将废水经过物理、化学方法等工艺处理达标后排放。总之,铁器脱盐时,环境友好型脱盐试剂和助剂的选择和适量使用是关键;铁质文物脱盐废水排放可能造成的环境污染问题应引起重视。     

纺织品文物回潮方法

主要介绍了纺织品文物回潮的方法及其各自的优缺点和适用范围。回潮方法可分为密闭式和敞开式两种模式,密闭式回潮法是最常用的回潮系统。在众多的回潮方法中,应用较多的包括饱和盐溶液法、超声波加湿器、水含体释放法、湿度自动控制回潮箱、低压吸力操作台和半透膜回潮法。在掌握纤维吸湿回潮的原理和回潮效果的影响因素,理解每件纺织品文物存在的问题、保护目的、工作条件、环境等因素,了解不恰当的回潮操作可能给纺织品文物带来的危害的前提下,根据工作条件选择恰当的回潮方法才是实际操作成功的关键。     

一种用于铁质文物保护的席夫碱缓蚀剂的制备及应用性能对比研究

近年兴起的席夫碱缓蚀剂综合了传统缓蚀剂的优点,具有良好的缓蚀效果,但传统的溶剂法制备使用无水甲醇作为提取剂,毒性大。为此,本实验在原有的溶剂法的基础上进行了改进,改用了无水乙醇作为提取溶剂,通过溶剂法制备了一种席夫碱缓蚀剂,并对其进行复配,以协同效应大大提高其缓蚀效率。通过盐雾试验、交流阻抗、极化曲线测试等方法评价其缓蚀性能,并与文物保护常用的Fertan、钼酸盐缓蚀剂的缓蚀性能进行了对比,优选出最适用于文物保护的缓蚀剂。最终得到复配后席夫碱缓蚀剂的缓蚀效率达到92.89%,远远超过其他缓蚀剂,体现出优异的性能。     

贺兰口岩画附近典型危岩体稳定性分析

通过前期现场调查,分析了贺兰口岩画的主要病害,提出岩画附近的危岩体是其中威胁较大的一类地质病害。根据现场勘察将贺兰口岩画附近不同状态的危岩体分为坠落式、滑塌式和倾倒式三类失稳模式。经过室内试验得到了岩石矿物组成、密度、气孔率、吸水率、单轴抗压强度等物理性质,并且利用Hoek-Brown准则、贯通率法以及岩石表面回弹值估算了危岩体与主控结构面的强度参数,例如单轴抗拉和抗压强度、变形模量、内摩擦角和黏聚力,然后利用不同失稳模式的计算方法进行稳定性分析。结果表明部分危岩体处于不稳定状态中,需要进行加固。     

Towards the application of desorption electrospray ionisation mass spectrometry (DESI-MS) to the analysis of ancient proteins from artefacts

The detection and identification of protein residues from archaeological artefacts has been the subject of considerable controversy over the past two decades, this controversy spurring the application of a range of different analytical methods. Part of the debate surrounds the ability of the methods to uniquely identify original proteins. Another is the apparent contradiction between the ease of extraction in the laboratory of residues that have managed to survive in sediment over millennia; some studies use simple solvents including water, whilst others claim that efficient extraction requires the destruction of the artefact.Desorption electrospray ionisation mass spectrometry (DESI-MS) offers the potential to directly analyse proteins bound to the surface of artefacts. The method permits desorption of analytes under ambient conditions directly from a wide range of surfaces with little or no sample preparation. This has already led to its application in a range of areas, including forensic analysis of trace levels of narcotic drugs. It does not require destruction of the artefact (e.g. by drilling or dissolution) and can work in concert with other methods (for instance it could be used as a screening tool prior to lipid extraction).Here we report the construction of a DESI-MS interface and consider the potential of the method to contribute to the debate surrounding the preservation of proteins on artefacts. The DESI-MS interface was fitted to a conventional ion trap mass spectrometer and tested using peptides and proteins artificially applied to the surface of flint flakes and potsherd samples. A range of intact proteins was analysed; the DESI interface identified test proteins up to a maximum molecular weight of approximately 20 kDa. Peptides generated from these and larger proteins could be detected using DESI-MS following tryptic digestion in situ. The collected data allowed identification of the originating proteins. The potential applications to archaeological science of this new analytical tool are discussed.