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31.
为了探究纸张的保存寿命,本项目对竹纸、宣纸、新闻纸、字典纸和构皮纸等5种纸张进行了干热加速老化实验,并对老化前后纸张的主要理化指标(返黄值、抗张指数、撕裂指数、耐折指数、聚合度、铜价和冷抽提pH值)进行检测。最后通过Pearson等级相关系数研究了上述理化指标与老化时间的相关性,从而揭示出纸张保存寿命预测的方法。研究发现5种纸张的抗张指数、铜价和聚合度与老化时间的相关性都较好。分别各有4种纸张的返黄值、冷抽提pH值和撕裂指数与老化时间的相关系数都在0.9以上,相关性非常好。仅有一种纸张的耐折指数与老化时间的相关性较好。本研究的结果对于大多数纸张保存寿命的预测具有参考价值。  相似文献   
32.
This paper presents a geochemical analysis of fragments of bituminous amalgam from H3, As‐Sabiyah (Kuwait), and RJ‐2, Ra's al‐Jinz (Oman). The fragments bear barnacles on one side and reed impressions on the other, and are thought to have been part of the coating of reed‐bundle boats. The material from H3 dates to between 5300–4900 BC, while that of RJ‐2 dates to 2500–2100 BC. Samples from both sites were geochemically compared to archaeological and ethnographic material from Kosak Shamali (northern Syria, c.5000–4400 BC), RH‐5 (Oman, 4400–3500 BC) and Baghdad (central Iraq, 1900 AD). The composition of the bituminous amalgams was studied in detail. Rock‐Eval Pyrolysis gave a measure of Total Organic Carbon in the samples, and allowed an initial comparison of the data sets using various parameters. Examination of the proportions of soluble and insoluble organic matter allowed an assessment of the quantity of vegetal matter added to the bitumen to make the bituminous amalgam. The composition of the Ra's al‐Jinz material was studied using X‐Ray Diffraction analysis and thin‐section petrography, in order to assess the proportions of various minerals in the bituminous amalgams. It was concluded that the recipe for the bituminous mixture used to coat reed‐bundle and wooden boats did not differ significantly from that commonly used to make ‘mortar’ for architectural purposes in Mesopotamia. Traces of animal fats or fish oils were not found in the analysed Ra's al‐Jinz material, in contrast to previous hypotheses regarding the composition of the mixture. Comparison of the gross composition of extractable organic matter (the constituents of pure bitumen, soluble in chloroform or dichloromethane) showed the progressive effects of weathering on the samples. The isotopic composition of the bituminous material from H3 and the other sites was then compared to that of bitumen seeps and crude oils from Mesopotamia, Iran and Oman. The most significant result is that the material from As‐Sabiyah originated in Kuwait, at a surface seep at Burgan, while the material from Ra's al‐Jinz had a source in northern Mesopotamia.  相似文献   
33.
Artefacts made of wood coming from archaeological excavations provide insights into human cultural behaviour of the past. They show how man utilised natural resources and how the development of woodworking techniques and artistic endeavour were developed. Within archaeological contexts, waterlogged anaerobic conditions generally preserve the appearance of artefacts, although wood is subject to severe decay processes. The said conditions can transform the original material into a new one, thus demonstrating specific differences from those of the “fresh” wood of the same species. In order to assess these new properties correctly, an integrated diagnostic approach is needed, one which includes a multidisciplinary (micromorphological, physical and chemical) evaluation of the state of preservation.  相似文献   
34.
This article presents the results of multidisciplinary studies conducted at Chagyrskaya – an Upper Pleistocene karst cave in the northwestern Altai where Middle Paleolithic stone tools and fossil remains of Neanderthals were found. Taphonomic aspects of the site are addressed, and results of science-based analyses including radiocarbon and paleomagnetic dating are presented. The deposits are similar to loess-like Upper Pleistocene loams of Western Siberia. Among the Middle Paleolithic industries of the Altai, the Chagyrskaya industry is paralleled only by that of Okladnikov (formerly Sibiryachikha) Cave. Both represent a local Middle Paleolithic Mousteroid facies, named Sibiryachikha after the eponymous site.  相似文献   
35.
在故宫古建大修中发现一批带有清代年款的琉璃瓦件,这些瓦件的制作原料、烧制工艺反映了当时的技术水平,同时也反映了国家对建筑琉璃生产的管理状况。本文着眼于琉璃瓦釉的研究,开展了成分分析、釉烧温度分析,并探讨了成分变化的原因、以及成分变化对釉的性能和胎釉匹配性的影响。研究结果表明:雍正至宣统时期,釉中PbO含量呈降低的趋势、SiO2含量呈升高的趋势,特别是雍正至乾隆时期变化较为明显。这一变化可能与乾隆元年对雍正朝琉璃瓦釉料用铅量的核减有关。釉的成分变化导致釉的流动点温度升高,釉的热膨胀系数降低。乾隆时期出现了一批胎釉热膨胀系数匹配性较好的瓦件。  相似文献   
36.
This study aims to simulate the long-term deterioration of architectural glazes exposed to open air in a highly polluted urban environment. A laboratory experiment—a 14-day long accelerated weathering test—on glazed roof tiles has been performed to reveal the damaging influence of contacting acid solutions originating from dissolved gaseous pollutants, mainly SO2. The studied tiles are made by the Hungarian Zsolnay factory and applied on two buildings in Budapest in the 19th and 20th century. The ceramics were covered mainly by lead glazes in the construction and lead-bearing alkali glazes in the renovation periods.

The solution of pH2 induced a greater dissolution, especially of alkali and alkaline earth metals (up to 2886 ppm), but less lead (up to 21 ppm) from the lead glazes of the construction periods. Newly formed lead sulphate (anglesite) on the corroded glaze parts precipitated on some lead-bearing alkali glazes, with moderate dissolution of alkali and alkaline earth metals (up to 396 ppm) accompanied by higher amount of lead (28–39 ppm). Based on the results, the main determining factor in the durability of glazes is mostly their chemical composition and less their preliminary degradation state.  相似文献   

37.
White Slip ware, both White Slip I and II, and Monochrome ware are Middle to Late Bronze Age Cypriot pottery types found across a large area of the Eastern Mediterranean region. A vast quantity of these wares has also been uncovered in Tell Atchana/ancient Alalakh in Hatay in southern Anatolia. We analysed a total of 56 White Slip (n = 36) and Monochrome potsherds (n = 20) from Tell Atchana using XRF, ICP–MS and petrographic thin‐section methods. The main aim of the study was to explore the compositional characteristics of the wares and to determine whether they are local imitations of the Cypriot White Slip and Monochrome wares or represent Cypriot exports to this region. The analytical results proved that White Slip I and II were produced from raw clay of mafic and ultramafic source rocks exposed in the Troodos Massif, available in the Limassol area of southern Cyprus and traded to Tell Atchana. Examples of Monochrome ware excavated in Tell Atchana were also imported to the region, most probably from east/north‐east Cyprus. These results demonstrate a close trading connection between Tell Atchana/Alalakh and southern Cyprus during the Middle to Late Bronze Age.  相似文献   
38.
Petrographic analysis of 49 sediments and 63 Neolithic ceramics from eight sites of Estremadura and six sites of the Algarve of central and southern Portugal, respectively, discerned distinct production technologies for each area. Raw materials available near archaeological sites were utilized. Fabrics that do not correspond to regionally available materials, however, indicate imports or migration. This suggests the existence of bidirectional maritime routes rather than south–north only, as predicted in current models of the neolithization of coastal Portugal. Seven ceramics and seven sediments were selected for elemental analysis. The results supported the patterns in the petrographic analysis.  相似文献   
39.
The study deals with the chemical composition of samples related to the production of a blue pigment/smalt. The samples examined come from the regions of Soví huť and Horní Blatná (north-west Bohemia) dating to the 16th and 17th centuries. These locations are often mentioned in relation to the discoverer of smalt production technology: Christopher Schürer. The aim of the study is to evaluate the chemical composition of samples from both localities as well as with respect to the ores occurring in the given regions. The samples can be divided into two basic groups. The first clearly represents smalt (potassium glass coloured with cobalt), while the second apparently constitutes the samples of the so-called ‘speiss’ (an aluminosilicate mass with metallic compounds). The analysis of the smalt confirmed the representation of minor elements bismuth and nickel (always) and uranium and molybdenum (rarely), which are found in Co ores from the Ore Mountains. The paper is the first to present the composition of actual blue pigment finds originating directly from the production sites, while the available literature has so far only reported the results of analyses of the pigments already used when referring to the Ore Mountains.  相似文献   
40.
Glass rings used to be one of the most common jewellery types in the 10th–13th centuries in Central Europe, especially Silesia. The popularity of this type of decoration in this area could indicate its local origin. The chemical composition of the glass seems to confirm this theory. The Silesian glass rings analysed in this paper were made of high‐lead alkaline and non‐alkaline glass or of lead‐ash glass. There was also a close relationship between the colour of the finished products and the chemical composition of the glass. This provides new data for the study of the problem of production and distribution of glass jewellery in Central Europe.  相似文献   
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