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1.
Four blue-glazed faience jars, on exhibition in the Louvre Museum, are referred to as the canopic jars of Rameses II. Their recent typological re-examination rendered this original assignment questionable. In order to clearly determine their use, a study of two successive organic residues from the canopic jars, using molecular biomarkers analysed by GC-MS and LC-MS and absolute dating by 14C, was initiated. The results revealed that these two materials were not contemporary to the reign of Rameses II. The first one, scraped from the interior face of one jar, was identified as an unguent made of coniferous oil and animal fat and dated from the Third Intermediate Period. The second one, originally stored with glued linen inside one jar, is likely an embalming substance, made of pure vegetable resin (Pistacia) and dated from the Ptolemaic Period. These results clarify a controversy which has been lasting over a century. The famous blue-glazed faience jars are not the canopic jars of Rameses II but are confirmed as situlae which were reused at least two times: first to store unguents during the Intermediate Period and later to store embalming packages of an unknown person during the Ptolemaic period.  相似文献   
2.
Despite uniform geochemistry 40Ar/39Ar ages of 0.6, 1.25, and 1.3 Ma on obsidians from a source flow (Worja) and from archeological artifacts at the sites of Kulkuletti (near Gademotta, Ethiopia) have been interpreted to suggest that they derive from different source flows of different ages. A further suggestion is that the magmatic source of the obsidian flows was chemically homogeneous between 1.3 Ma and 0.6 Ma. Chemical analysis of these obsidians indeed suggests that they derive from a single flow. Reexamination of the argon isotopic data reveals that argon isotopes may have been fractionated within the flow, so that the assumption of an atmospheric 40Ar/36Ar ratio of 295.5 is inappropriate to use for computing ages. Three groups of data are apparent, and internally all yield ages near 1.3 Ma if the intercept value for 40Ar/36Ar from an isotope correlation plot is used for computation instead of using the atmospheric ratio. The Soret thermal diffusion effect provides a possible mechanism of fractionation of argon within the obsidian flow that is of approximately the right magnitude to explain the observations by in-diffusion of already fractionated atmospheric argon.  相似文献   
3.
为尝试比较汞同位素分馏数据来跟踪朱砂矿源,对成都市青白江区双元村战国墓地11个墓中的朱砂样本进行汞同位素测定。汞同位素分馏值彼此相似,应来自同一矿源。δ202Hg值从-1.18‰到-0.84‰不等(均值-1.010‰,标准误差0.105‰,样本数11个),和已发表的其他矿源汞同位素分馏值均存在差异。通过数据比较,可知成都青白江区双元村墓地不同墓中的漆器朱砂颜料汞同位素质量分馏值分布集中,极有可能来自同一矿源。如对周边地区朱砂矿进行汞同位素分馏值测量,有可能找出该墓地的矿源。  相似文献   
4.
In 1845, an expedition, commanded by Sir John Franklin, set out to try and discover the north-west passage. All 129 men on this ill-fated voyage perished. Over the years, skeletal remains associated with the final throes of the expedition have been located on and near King William Island, Nunavut, in the Canadian arctic. In general, even a tentative personal identification for these remains has proved impossible. An exception is some skeletal remains that were recovered in 1869 and brought back to England and interred beneath the memorial to the Franklin expedition in Greenwich. In the 19th century, these were tentatively identified as of one of HMS Erebus’s lieutenants, Henry Le Vesconte, a conclusion that has been widely accepted in studies of the Franklin voyage. Renovations to the monument in 2009 provided an opportunity for scientific examination of the remains, and to re-evaluate the personal identification made nearly 140 years before. The current work, which is the first modern scientific analysis of a fairly complete skeleton associated with the Franklin voyage, describes the remains and the artefacts interred with them, discusses the pathological conditions present, and evaluates the personal identification using osteological techniques and isotope geochemistry. Results indicate that the remains are of an adult male of European ancestry. Although some writers have suggested that scurvy or tuberculosis may have been important causes of morbidity and mortality on the Franklin expedition, osteological analysis and, in the case of tuberculosis, DNA analysis, provided no evidence for their presence in these remains. Isotopic studies indicate that the personal identification as Le Vesconte is unlikely to be correct. From the isotopic results and forensic facial reconstruction, HDS Goodsir, an assistant surgeon on the expedition, appears a more likely identification, but the results do not allow a firm conclusion.  相似文献   
5.
S. Klein  T. Rose 《Archaeometry》2020,62(Z1):134-155
Until today, raw material information of copper (Cu) objects is mostly gained from impurities and trace elements and not from the Cu itself. This might be obtained using its stable isotopes. However, isotopic fingerprinting requires the absence of fractionation during the smelting process. The Cu isotope evolution during outdoor smelting experiments with Cu sulphide ore was investigated. It is shown that external materials, in particular furnace lining, clay, manure and sand, alter the isotopic composition of the smelting products. Cu isotopes are fractionated within low viscosity slag derived from matte smelting. The produced metallic Cu has a Cu isotope signature close to the ore.  相似文献   
6.
The management and conservation of animal species should be based upon a long-term analysis that considers its geographical distribution and feeding patterns. The study of carbon and nitrogen stable isotopes on skeletal remains provides a quantitative approach to the paleodietary reconstructions and constitutes a potent tool for comparing behavioral aspects of the fauna. In this paper we present the first set of isotopic values for modern and archaeological samples of Huemul (Hippocamelus bisulcus) from the forests of Central-western Patagonia, Chile. Contrary to initial expectations, our analysis indicates that there is no evidence of an important incidence of the canopy effect on the δ13Ccollagen values, which we suggest is due to an ecological selection that drives the huemul to focus its predation on open sectors within the forest. On the other hand, a wide range of δ15Ncollagen values for huemul was verified. This could reflect the N impoverishment of the forest soils and provide an interesting ecological indicator. The long-term information offered by the archaeological record provides the necessary context for decision-making conducive towards the preservation of Hippocamelus bisulcus in Patagonia.  相似文献   
7.
During MIS (Marine Isotope Stage) 9 and the transition to MIS 8 – around 350–300,000 years ago – some lithic assemblages in Europe reflect marked transformations in technical behavior. These transformations involved the standardization of products and the development of diversified and elaborated débitage methods which are considered to be markers of the transition from the Lower to the Middle Palaeolithic i.e. from Mode 2 to Mode 3. Taking the analysis of the sites of Orgnac 3 (Ardèche, France) and Cave dall’Olio (Emilia Romagna, Italy) as a starting point, this paper discusses the variability of these assemblages in Southern Europe as well as the social and anthropological implications of the emergence of new technical behavior. It also aims to show that common features existed both in Northern and Southern Europe. The development of more complex technical systems on a progressively wider territory and at an increasingly earlier age argues in favor of the hypothesis of a close connection with the process of “Neanderthalisation”, possibly accompanied by the transmission of ideas through extensive social networks.  相似文献   
8.
Saltpetre constitutes one of the major ingredients of gunpowder, which was a driving force during the political changes in late medieval to early modern times in Japan. Two types of model saltpetre mineralization are studied. One represents efflorescent saltpetre formed as the byproduct of indigo dye manufacture, whereas the second is anthropogenic, derived from relict nitre‐beds. Here, oxygen and nitrogen isotopic analysis, as expressed by δ18O and δ15N notations, is applied. The calculated δ18O values for ambient water, responsible for the microbial‐mediated oxidation of ammonium into oxygen in nitrates, tended to have higher ranges than average local meteoric waters of the relevant regions. An overall trend could be seen, showing the apparent positive nitrogen isotopic fractionation during the microbial transformation from initial organic nitrogen into nitrate product. Dual isotopic analysis for industrial nitrates provides a useful tool for investigation of the provenance of historic gunpowder. Present anthropogenic saltpetre involves positive control over temperature–moisture regimes and oxygen fugacity during formation, the process being distinctive from those prevailed in British India and other European countries.  相似文献   
9.
This paper presents a new approach to the isotopic measurement of diagenetically altered archaeological bone apatite carbonate. We describe how the existing differential dissolution method may be combined with a new approach to remove diagenetically reformed material on the basis of its greater specific gravity. We show that heavier, more diagenetically altered fraction has a higher (altered) δ13C and also increased crystallinity within one individual. In addition, we proposed one potential tool to check the validity of bone carbonate by comparing bone collagen, enamel carbonate and bone carbonate values of δ13C and radiocarbon content from the same individual. In the case of Danebury cattle, we estimated the biogenic δ13Capa value for DC83 and DC89, although it is still difficult to overcome diagenesis in order to meet the expected value, which is shown to be 1.9‰ (DC83) and 3.5‰ (DC89).  相似文献   
10.
Laboratory experiments have been performed to determine diffusion coefficients of natural gas components (methane, ethane and nitrogen) and isotope fractionation effects under simulated in situ pressure (up to 45 MPa effective stress) and temperature conditions (50–200°C) in water‐saturated pelitic and coarse‐grained rocks. Effective diffusion coefficients of molecular nitrogen (0.39 × 10?11 to 21.6 × 10?11 m2 sec?1 at 90°C) are higher than those for methane (0.18 × 10?11 to 18.2 × 10?11 m2 sec?1 at 90°C). Diffusive flux rates expressed in mass units are generally higher for N2 than for CH4. Both methane and (to a lesser extent) nitrogen diffusion coefficients decrease with increasing total organic carbon (TOC) content of the rock samples because of sorption processes on the organic matter. This effect decreases with increasing temperature. Effective diffusion coefficients increase upon a temperature increase from 50 to 200°C by a factor of four. Effective diffusion coefficients and steady‐state diffusive flux decrease with effective stress. Stationary diffusive fluxes drop by 50–70% for methane and 45–62% for nitrogen while effective diffusion coefficients are reduced by 38% (CH4) and 32–48% (N2), respectively. Isotope fractionation coefficients of diffusive transport are higher for methane (?1.56 and ?2.77‰) than for ethane (?0.84 and ?1.62‰). Application of the experimental results to geological systems show that diffusive transport has only a low transport efficiency. Significant depletion of natural gas reservoirs by molecular diffusion is only expected in cases of very poor caprock qualities (in terms of thickness and/or porosity) and over extended periods of geological time. Under these circumstances, the chemical and isotopic composition of a gas reservoir will change and maturity estimates based on these parameters may be deceptive. To account for these potential effects, nomograms have been developed to estimate diffusive losses and apply maturity corrections.  相似文献   
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