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61.
Lead concentrations in a number of bones and soil samples taken from the same graves at the site of Bordesley Abbey were significantly correlated. Statistical analysis of the results indicated that 59% of the variation in the bone lead concentrations was due to contamination from the soil.A study of the distribution of lead in a tooth from the Romano-British site at Cirencester by fast particle activation analysis indicated that virtually all the lead was on the external surface, indicating post-mortem absorption.These results strongly suggest that lead is absorbed by skeletal tissue after death even in soils which have an alkaline pH. In the light of these findings, suggestions are made for the strategies which might be adopted for further research in this area.  相似文献   
62.
This work proposes a multi‐analytical approach to determine the additives in historical mortars, the use of which is widely described in bibliographical sources, but has rarely been reported in the literature. A protocol to thoroughly analyse mortars was created (optical microscopy, X‐ray diffraction, infrared spectroscopy, thermal analyses and gas chromatography – mass spectrometry). These techniques, which had already been carried out on samples from various sites from the Roman to the modern era, determined that additives had only been used in the mortars from the internal masonry at our sampling site: the medieval military shipyard of Amalfi (Italy). The investigations yielded information on the production technology, and FT–IR and GC–MS revealed a saccharide material‐based additive in the mortars, of plant origin. The FT–IR spectra suggested the presence of a natural gum, which has been used since ancient times to strengthen the cohesion properties of mortars and their resistance to tensile stress.  相似文献   
63.
为识别文物中蜡质原材料,以及文物保护修复工作中常用蜡类材料的类别,研究通过在线甲基化热裂解-气相色谱/质谱联用技术对蜂蜡、棕榈蜡、小烛树蜡、地蜡、石蜡等蜡类材料进行分析检测。研究发现:蜂蜡的主要裂解产物为直链烷烃、直链脂肪酸、直链醇、含羟基脂肪酸;棕榈蜡为直链醇、直链脂肪酸、脂肪酸衍生物;小烛树蜡为直链烷烃、直链脂肪酸、直链醇、羽扇豆醇及其衍生物、计曼尼醇及其衍生物、脂肪酸衍生物;地蜡、石蜡等矿物蜡的主要裂解产物为直链烷烃。不同蜡中裂解产物的种类及其相对含量分布规律均有所区别,因此通过在线甲基化热裂解-气相色谱/质谱联用技术可以实现不同种类蜡的区分。通过所建立的方法及总结的数据,研究推断故宫旧藏清代紫檀木边座嵌玉人鸂鶒木山水图插屏中镶嵌珐琅构件所用棕色蜡为蜂蜡,所用白色蜡为矿物蜡及少量蜂蜡。本研究所建立方法易于推广,适用于文物中蜡类材料的准确、快速识别。  相似文献   
64.
热脱附-气质联用法作为一种无损分析技术,可以用于测定函套中的挥发性物质。为此,用Tenax-TA吸附管对10种目标化合物进行吸附,在优化的色谱条件下,苯、甲苯、乙酸正丁酯、乙苯、间/对二甲苯、苯乙烯、邻二甲苯、正十一烷和糠醛等组分相关性良好。对实际样品进行测定,可以实现函套等装具中挥发性有害物质的分离分析。研究结果对纸质文献的保护有参考作用。  相似文献   
65.
Ten Early Bronze Age (BzA1, 2200–2000 BC) copper artefacts from the central Valais region from Switzerland were studied for their elemental composition and lead isotope ratios. In order to answer the archaeological question of a local copper supply, a database for copper minerals across the Valais (Switzerland) has been established. This database contains 69 data on lead isotope ratios as well as additional information on the minerals and geochemical associations for copper minerals from 38 locations in the Valais. Comparisons of the artefacts were also made with data pertaining to minerals from various deposits from Europe and Anatolia taken from the literature. The provenance of the materials is very diverse. Some of the data are compatible with the data from the copper mineral deposits of the Valais region. Moreover, three copper lunulae were identified as possibly Tuscan, which suggests contacts between Italy and the Valais region. This pattern also establishes a multiplicity of provenances for the metal and cultural influences in the Alpine environment of the Rhone Valley of Switzerland at the beginning of the Early Bronze Age.  相似文献   
66.
Archaeological excavations in the Areni-1 cave complex in southeastern Armenia revealed installations and artifacts dating to around 4000 cal. BCE that are strongly indicative of wine production. Chemical evidence for this hypothesis is presented here using a new method to detect the anthocyanin malvidin that gives grapes and pomegranates their red color. Using solid phase extraction (SPE) and alkaline treatment of the samples, followed by combined liquid chromatography-tandem mass spectrometry (LC-MS/MS), this method was applied to authentic standards and four ancient potsherds from Armenia and Syria. A positive result was observed for two of the samples from the Areni-1 cave complex, adding evidence supporting the hypothesis that wine was produced in the Near Eastern highlands in the Late Chalcolithic Period.  相似文献   
67.
The effects of heat on the stable carbon and nitrogen isotopic ratios of collagen in bone were studied. Boiling or roasting did not change the δ13C and δ13N values by more than 1‰. More extreme heating, such as might occur if bones were burned or a body cremated, shifted δ13C and δ15N values by as much as 5 and 4‰ respectively. These large shifts were accompanied by changes in the atomic carbon-to-nitrogen ratios of the collagen. These results indicate that collagen samples extracted from prehistoric bones which display anomalous atomic carbon-to-nitrogen ratios may have been subjected to heating extreme enough to have altered their 13C12C and/or 15N14N ratios and therefore should not be used for dietary reconstruction.  相似文献   
68.
Tin's small mass fractionation and the lack of accepted reference standards have hindered Sn isotopy in archaeology and conservation science. Because of ore field variation and potential fractionation during ore reduction, attempts to determine artefacts’ ore sources have been limited. After norming the fractionations to NIST 3161a (Lot #070330), significant differences in Sn isotope mass fractionation in Judaean bronze ‘Biblical’ coins minted by different rulers during the first centuries bce and ce were discovered. These variations and those in δ 65Cu and 206Pb/204Pb are connected to historical events in the Levant.  相似文献   
69.
The production of oil and wine was an important aspect of the ancient Mediterranean economy. Among the material remains related to the production of these substances, installations used for their production provide evidence that is still unexploited. Although archaeological studies have been carried out on these installations, problems can arise in the identification of their function, as wine and oil production structures can be similar and the archaeological traces insufficient to establish which substance was produced.  相似文献   
70.

The development of the gas centrifuge in the 1960s revolutionized the production of enriched uranium. More simple and efficient than gaseous diffusion, the centrifuge offered countries a means of producing enriched uranium independently of America. For Britain, the centrifuge possessed political as well as economic advantage. It provided the opportunity for Britain to share nuclear knowledge with its European partners, so improving the prospect of successful admission to the European Common Market. In Washington, the prospect of a joint European centrifuge project received an ambivalent response. The State Department, keen to foster a strong Europe as a bulwark against Soviet expansionism, welcomed collaboration. In contrast, the Atomic Energy Commission, charged with maintaining US nuclear security, sought to block the venture on the grounds that it infringed US law. This paper reviews this debate, examining Anglo-American nuclear relations in the context of Britain's entry into the European Common Market. It argues that Britain was determined to establish a purely European solution to the question of uranium supply even if this led to a breach in Anglo-American relations.  相似文献   
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