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采用显微观察、X射线衍射物相分析和X射线荧光光谱成分测试等手段,对湖北省巴东县雷家坪遗址六朝时期墓葬出土的若干精美“珠饰”进行了观察和分析,阐述了它们的特征,确定其材质;并与其他遗址出土不同时期的玻璃制品进行比较,发现其配方和我国西周至汉代玻璃,以及西方传统玻璃差别甚大。结合考古背景资料分析,这批珠饰很有可能是我国古代工匠在原有玻璃技术基础上,借鉴和吸收了外来玻璃的制造技术,在中国境内自行烧制的。  相似文献   
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J. HARA  N. TSUCHIYA 《Geofluids》2005,5(4):251-263
Sodic alteration assemblages including clinoptilolite, mordenite, analcime and Na‐montmorillonite were locally observed in sediments in the eastern part of the Hachimantai geothermal region, northeast Japan. This study investigated the mechanisms of sodic enrichment in the sediments during alteration. Kinetic results for water/rock interaction experiments are reported here. Batch‐type experiments were conducted at 150–250°C under saturated vapor pressure. Pyroclastic rocks dissolved incongruently in these experiments, and the solubility and dissolution rates among elements varied as follows: the apparent steady‐state concentrations of major elements are Si > Na ? K > Ca > Al and the order of the dissolution rates is Si > Al > Na ? K > Ca. Na had the highest steady‐state concentration and fastest dissolution rate of the alkali and alkali earth metal ions. Based on surface analysis of plagioclase, dissolution was effected via a reaction layer of Na‐montmorillonite on the mineral surface. Additionally, a reaction model constructed based on the experimentally observed reaction mechanism quantitatively explains the dissolution behavior. These results show that Na‐montmorillonite can be precipitated by pyroclastic rock/meteoric water interactions without seawater involvement: the Na is derived from the host rocks.  相似文献   
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Archaeological wood, as most of natural materials, is slowly decomposing on the archaeological site due to various biological factors. Rapid and accurate estimation of the degradation level is extremely important for optimal restoration and conservation. The goal of this research was to verify the effectiveness of Fourier transform near infrared (FT-NIR) spectroscopy for archaeometry. The important advantage of the NIR spectroscopy is its accuracy, simplicity and ability to perform very high number of tests without needs of any destruction to the workpiece. Five oak pieces of the archaeological wood collected from waterlogged sites in Poland have been used. Cellulose and lignin contents, as well as crystallinity and the degree of polymerization were measured with standard reference methods and compared to the contemporary wood. The near infrared spectra represent all the physical/chemical changes of the wood due to waterlogging. This technique was successfully validated in rapid estimation of the cellulose and lignin contents. The method explored in this research might be a novel tool assisting experts in evaluation of the degradation state of archaeological and historical wooden materials.  相似文献   
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J. HARA  N. TSUCHIYA 《Geofluids》2009,9(1):24-38
Hydrothermal water–(pyroclastic) rock interactions were examined using flow-through experiments to deduce the effect of mass transport phenomena on the reaction process. A series of experiments were conducted over the temperature range 75–250°C, with a constant temperature for each experiment, and at saturated vapour pressure, to estimate the apparent rate constants as a function of temperature.
Based on the chemistry of analysed solutions, the water–rock interaction in the experiments was controlled by diffusion from the reaction surface and by the existence of a surface layer at the rock–fluid interface, which regulated the chemical reaction rate. The reaction progress depended to a high degree on flow velocity and temperature conditions, with element abundances in the fluid significantly affected by these factors. Mass transport coefficients for diffusion from the rock surface to the bulk solution have been estimated. Ca is selectively depleted under lower temperature conditions ( T  < 150°C), whereas Na is greatly depleted under higher temperature conditions ( T  > 150°C), and K reaction rates are increased when flow velocity increases. Using these conditions, specific alkali and alkali earth cations were selectively leached from mineral surfaces. The 'surface layer' comprised a 0.5–1.8 mm boundary film on the solution side (the thickness of this layer has no dependence on chemical character) and a reaction layer. The reaction layer was composed of a Si, Al-rich cation-leached layer, whose thickness was dependent on temperature, flow velocity and reaction length. The reaction layer varied in thickness from about 10−4 to 10−7 mm under high temperature/low fluid velocity and low temperature/high fluid velocity conditions, respectively.  相似文献   
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Research on regional economic development increasingly embraces more nuanced perspectives on the evolution of clusters, industries and agglomerations. The extent to which the emergence and decline of clusters can be directed with intentional regional development strategies is, however, a major point of discussion. The article links the cluster life cycle concept to regional development strategies in order to examine the trajectory of Europe’s largest chemical complex in and around the Port of Antwerp (Belgium). This chemical cluster has matured and currently is in a state of stability. Although the cluster did not experience growth over the last decades in terms of new entrants, it did transform internally and maintained its importance as a production centre. Thus, whereas lock-in mechanisms hampered growth, they also prevented the cluster from going into a state of decline. We argue that while regional development strategies stimulated new emerging clusters in the Flemish region, vested interests in the port and associated lock-in mechanisms have resisted such developments in Antwerp. New growth trajectories based on the chemical cluster were therefore difficult to recreate in the Antwerp region.  相似文献   
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The trace element boron is present in most ancient glasses as an impurity, and high boron (≥ 300 ppm) marks raw material sources that are geologically specific and relatively uncommon. Recent analyses of Byzantine glass with high boron contents suggest that glass‐making was not limited to the traditional regions of the Levant and Egypt, and a production origin in or near western Anatolia is proposed. Glass bracelets from ?i?n al‐Tīnāt in southern Turkey give fresh evidence for the production and circulation of high‐boron glasses that closely correlates with object typology. The patterning of findspots suggests that high‐boron glass was closely connected to the Byzantine world.  相似文献   
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本文报道 NMF-1防霉剂的合成,理化数据,毒性检测,防腐蚀和抗微生物试验以及对纸张、纺织品性能、色彩的测试.该防霉剂有防霉杀虫片、防霉浆糊添加剂、防霉防虫乳剂以及溶刺型防霉防虫液,不仅适用于文物、图书、档案的防霉,而且在其它领域亦能得到广泛的应用.  相似文献   
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Chang'an (now Xi'an) was the capital of the Western Han Dynasty and the starting point of the Silk Road. In the light of the importance of Chang'an as the centre of politics, economy and cultural interaction, the overarching question proposed in this paper is focused on its role in the mirror production and distribution network during Han period. On the basis of chemical and lead isotopic analyses of 34 Han mirrors, this paper discusses the potential existence of a mirror production centre in Chang'an. Meanwhile, a comparative study with mirrors uncovered from the south‐western frontier and from Central Asian and North‐East Asian countries offers new insight into these related issues.  相似文献   
10.
We have determined the composition of rock art pigments from two megalithic barrows located in the north of Portugal. The use of XRD, SEM–EDS and FT–IR spectroscopy confirmed the presence of hematite and kaolinite in the red pigments from the Eireira barrow, and kaolinite in the white pigment from the Leira das Mamas barrow. The organic composition of the pigments was studied by GC–MS, suggesting that the red sinuous lines and dots from the Eireira barrow were prepared with cooked or heated algae and/or aquatic plants, with egg as binder, while the white pigment from the Leira das Mamas barrow revealed a mixture of vegetable oils for kaolinite moulding, which could be stabilized by temporary exposure to high temperatures. The multi‐analytical approach used on this study of megalithic pigments allowed the recovery of important data about north‐western prehistoric communities, namely the way in which they exploited existing resources and their ability to transform them.  相似文献   
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