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61.
A number of charred surface residues, adhering to ceramic containers, were obtained from various coastal and inland sites in north‐west Europe dating from the sixth to the fourth millennium cal bc . In order to investigate the use of these vessels and in particular to identify any marine products, the residues were subjected to carbon and nitrogen stable isotope analysis. Variation in carbon isotope ratios between different samples indicated that some vessels may have been used to process marine products. This analysis was corroborated by specific identification of aquatic products following structural and isotopic characterization of lipids extracted from selected samples.  相似文献   
62.
In order to explore the possibility that intramolecular differences in the δ13C value of bone collagen can provide useful infomation for isotopic dietary analysis, a method for reliably measuring the δ13C value of the peptide-bonded carboxyl carbons in collagen was developed and applied to a wide range of modem and ancient species, including humans. Carboxyl carbons were selectively removed as CO2 by decarboxylation of collagen hydrolysates with ninhydrin (2,2-dihydroxy-l,3-indanedione). Carboxyl carbons were usually isotopically heavier than the total carbon in the collagen, with differences ranging from -0.9 to 4.0%c. Animals at higher trophic levels and with more positive δ15N values usually had smaller differences than the lower animals while humans had the largest range, reflecting their larger range of diets.  相似文献   
63.
This paper presents a new method for the isolation and isotopic analysis of some individual amino acids from proteins. The technique and its constituent steps are discussed; then isotopic analyses of amino acids from several samples of bone collagen from the Late Roman site of Poundbury, Dorset, UK are presented. The applications of the method are discussed, as well as some advantages of this technique relative to other methods. Although developed for use with archaeological bone collagen, the technique is equally applicable to other proteinaceous materials. The use of reversed‐phase HPLC avoids problems of isotopic fractionation inherent in using ion‐exchange HPLC. Amino acids are isolated preparatively, allowing both carbon and nitrogen isotopic values to be measured on a single sample using CF‐IRMS. Since amino acids are isotopically analysed in an underivatized form (unlike GC‐C‐IRMS), the method also presents the possibility of collecting the CO2 generated during CF‐IRMS: this would allow the subsequent dating by 14C‐AMS of individual amino acids isolated from archaeological samples.  相似文献   
64.
Numerous marble artefacts were among the extraordinary findings excavated at the Roman burial area of Faschendorf (Carinthia, Austria). The provenance of marble objects, particularly in the Roman provinces, is mostly unclear. Predominantly Mediterranean marbles have been used, but there are also some marble occurrences in the eastern Alpine regions that were exploited in those times. Besides a mineralogical–petrographic analysis, grain‐size evaluation in particular, and the determination of carbon and oxygen isotopes allow an effective characterization of the Faschendorf materials. Their provenance from the Gummern Marble complex in Carinthia is very likely.  相似文献   
65.
An updated database of Ephesos marbles including 244 samples from 16 quarrying districts is reported. The unknown Greco Scritto quarries near Hasançavuslar and the Bigio marbles from the quarries of Belevi and of Mt Panayir are also presented. The paper, however, is mostly devoted to the identification of the Ephesos white marbles, whereas the problems posed by the Bigio and Greco Scritto varieties are deferred to future work. The samples have been characterized by isotopic analysis, EPR spectroscopy and additional petrographic and optical properties. Owing to the complex geology of the region, the white marbles of Ephesos exhibit rather inhomogeneous properties and are conveniently classified into four marble groups, which can be almost completely discriminated. The problem of distinguishing the Ephesos white marbles from other similar varieties has been dealt with by statistically comparing the Ephesos samples with all the similar, medium‐grained varieties present in the marble database. Although some of the four Ephesos groups can be reliably identified, general solution of the discriminant problem is difficult. Historical archaeological information is needed to reduce the complexity of the problem by eliminating unlikely provenances. In this way relevant problems, such as the discrimination between Ephesos and Proconnesos marbles, can be solved.  相似文献   
66.
The excavation of a barrow at Upper Ninepence, Walton in the Welsh Borderlands, U.K., revealed two phases of occupation associated with two different ceramic traditions, namely Grooved Ware (2500bc) and Peterborough Ware (3000bc). The Grooved Ware and Peterborough Ware pits seem to have a mutually exclusive distribution on the site. Screening of the sherds for lipid residues has revealed the presence of remnant fats in a remarkably well-preserved state considering the age of the finds. Investigations of various chemical characteristics of the remnant fats from absorbed and carbonized residues have enabled distinctions to be drawn between fats from non-ruminant (e.g. porcine) and ruminant (e.g. ovine or bovine) origins. Significantly, both ruminant and non-ruminant fats are found associated with the Grooved Ware whereas only ruminant fats are found associated with the Peterborough Ware. The assignments are based upon the distributions of solvent-extractable lipid components and the compound-specific stable carbon isotope values of the major n -alkanoic acids. The results reveal differences in vessel use and indicate possible changes in patterns of animal exploitation or dietary preferences between the two phases of occupation. The results illustrate the importance of residue analysis in archaeological investigations, particularly at prehistoric sites where evidence from faunal remains is limited or absent.  相似文献   
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