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101.
Historic shipwrecks frequently contain a large proportion of wrought-iron tools, fasteners, and other types of artefacts. Encrustations readily form around such objects in many marine environments. Depending on many factors, the iron objects inside these encrustations may be well preserved, completely disintegrated, or poorly preserved but still present. The latter type of encrustation is every conservator's nightmare because removing the encrustation yields merely a poorly preserved artefact still in need of extensive additional conservation. Neatly separating the artefact from its encrustation in order to obtain a natural mould for casting is generally impossible. Having encountered this problem many times, the authors began to experiment with the extraction of metallic iron from poorly preserved encrusted artefacts using galvanic dissolution. Data on rates of dissolution were gathered for three experimental configurations. The results of a test conducted on an encrusted artefact were promising, but inconclusive.  相似文献   
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Optically stimulated luminescence (OSL) is applied to quartz extracted from mud mortar collected from Chavín de Huántar, an early Andean monumental center. The samples appear to have been only partially exposed to sunlight during construction, so a minimum age model is applied to equivalent dose distributions. Complications, including complex radioactivity, low sensitivity of the quartz, and limited sample, prevent high precision, but the 14 dates obtained cluster around 1000 BC largely in agreement with radiocarbon assays on charcoal also collected from the mortar. Results suggest a relatively rapid construction for the monument. This work develops OSL as a method for directly dating architectural mortar.  相似文献   
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This article proposes to analyse the relationships betweenanthropology andindigenism in Brazil. To do so it considers the migration process of indigenism as a form of knowledge from the Mexican political field to the Brazilian. It affirms that this kind of knowledge had its reception considerably inflected by «traditions of knowledge» for governing populations which developed from colonial sources through time. This analytical perspective is part of an anthropology of colonialism, since it takes as its object Brazilian public administration considering some of its aspects as technologies for the government of multicultural populations.  相似文献   
104.
The fruit (pods) of Prosopis (Fabaceae) are frequently recovered from pre-Hispanic Argentinian archaeological sites, suggesting that this genus was of importance in ancient economies in this region. Yet it is only recently that archaeobotanists have begun to carry out systematic research into this genus. Therefore many questions remain to be addressed concerning the food value of Prosopis fruit, and its potential contribution. This paper examines starch from the pods of two species, Prosopis flexuosa and Prosopis chilensis, for the purposes of describing and classifying their morphological features and biometrical parameters. Pods of both species were gathered from two extremes (northern and southern) of the Hualfín Valley, Catamarca, Argentina. Starch abundance is estimated and compared with that of Zea mays, an economically important plant with high concentrations of starch. This paper reveals that Prosopis pods contain very low amounts of starch compared to starch-rich edible species. Despite this, the recovery of Prosopis starch grains can be successfully used to assess archaeological tool uses. Prosopis starch grains were found to be highly variable in shape. Grain size ranged between 10 and 20 μm. Granule irregularity and the high birefringence under polarized light are two of the most important diagnostic features. No significant statistical differences were found in the structure (morphology, size and hilum) of the starch of the same species from both localities. Finally, the implications for the role of this plant in past societies are discussed.  相似文献   
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Abstract  

This paper primarily presents analyses from geophysical data and archaeological remains collected at one of a few known sites to the west of Lake Chad associated with fired-brick structures. It reports on previous fieldwork at the location, considers its alleged relationship with the early history of the Borno kingdom and then turns to present new data that provide fresh insights into the physical appearance, dating, material remains, economy and environment of the site. A brief discussion of the historical purpose of the fired-brick structures and the site itself concludes the paper.  相似文献   
109.
The identification of chemical activity residues on archaeological surfaces requires the analysis of large numbers of samples, which can be costly and time consuming. Researchers wishing to apply sediment chemistry often are confronted with a dilemma of which technique to use and how to accommodate sediment chemistry into their budget. We propose an approach to the identification of chemical activity residues in which semiquantitative spot tests, which are cheap, quick, and easy to apply, are employed as an initial phase of analysis in order to leverage the results of more time-consuming and costly instrumental techniques. Three examples that pair spot tests with gas chromatography-mass spectroscopy and inductively coupled plasma-optical emission spectrometry analysis show that spot tests successfully identify areas of interest. This approach can save both time and research funds.  相似文献   
110.
This paper examines skeletal and ancient DNA evidence in the study of suspected tuberculosis infection in the late pre-Hispanic and Colonial-era Lambayeque Valley Complex, north coast Peru (A.D. 900–1750). We integrate information on macroscopic lesion characteristics and distribution, radiographic and CT scan imagery, and analysis of Mycobacterium tuberculosis complex rpoB and IS6110 ancient DNA (aDNA) sequences. Destructive lesions were observed in the vertebral bodies of three precontact indigenous adult males, one colonial adolescent female, and in the cranium of a Colonial-period subadult. Assessment of lesion morphology and distribution led us to consider multiple diseases, but tuberculosis represents the most likely diagnostic option in all individuals. DNA was poorly preserved in all samples, but an IS6110 sequence was amplified in one precontact individual consistent with macroscopic diagnosis. These findings expand the geographic and temporal extent of tuberculosis to the late pre-Hispanic and Colonial north coast of Peru to highlight potential synergisms between diet, settlement patterns, and the evolution of Andean tuberculosis before and after European conquest. Moreover, this study helps focus several key questions in Andean tuberculosis research, including possible reassessment of the presence of the IS6110 sequence in the pre-Columbian Americas. Methodological considerations include differential diagnosis – especially with incomplete skeletons – and limitations of aDNA studies underscoring an approach integrating macroscopic, radiographic, and molecular lines of evidence in the paleopathological investigation of one of humankind’s most devastating and destabilizing diseases.  相似文献   
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