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21.
    
The Yuzhen Palace is one of the nine palaces in the Ancient Building Complex built by order of the Yongle Emperor during the Ming dynasty. The buildings were built with dressed black bricks. As a result of the planned national South–North Water Diversion project, the water level in the Danjiangkou Reservoir that surrounds the Yuzhen Palace was expected to rise by approximately 15 m. To avoid submersion of the site, three gates were elevated by 15 m in 2013 and other buildings dismantled, for later reconstruction. The characterization of the construction materials has therefore become of primary importance. Here, we present results on the plasters of the Longhu Hall. The analysis of materials involved a multi‐analytical approach combining optical and electron microscopy with X‐ray and vibrational spectromicroscopies and thermogravimetry. The results indicated the use of two earthen plaster layers and a whitewash finish coating applied over a thin preparatory intermediate layer to improve the adherence of the finish coating to the earthen plaster. Ramie and straw fibres identified in the earthen plasters were added to reduce shrinkage and cracking during drying. The raw materials used and the application technique pointed to a well‐established construction industry using traditional earthen building materials together with lime technology.  相似文献   
22.
Dietary reconstructions based on plant microfossils, such as starch grains and phytoliths, have been useful in increasing our understanding of past human populations. Microfossils have been recovered from sediments, stone tools, and, more recently, dental calculus. Methods for recovering microfossils from dental calculus have yet to be firmly established and there is some question about potential damage to the teeth. Using a sample of teeth from the middle Holocene site of Tell al-Raqā'i, Syria, we tested using a dental pick to sample the calculus. ESEM images taken before and after sampling show no damage to the enamel surface, and examination of the recovered microfossils show that this method provides ample material for study, even when not all of the calculus is removed from the tooth. Preliminary identification of the plant microfossils suggests that these individuals were consuming a variety of plant foods, but that domesticated cereals such as wheat and barley made up a surprisingly small portion of their diet.  相似文献   
23.
The taphonomic or formation processes of desiccated and carbonized plant remains are reviewed and compared. Both types of assemblage frequently consist of material of mixed origin, but despite a high degree of mixing, the various routes of entry are still identifiable, and it is concluded that archaeological plant assemblages are more robust than often assumed. Case studies where the accurate identification of the formation processes has been critical are examined and guidelines on how to assess the formation processes are presented. It is argued that the coherence of archaeobotanical assemblages is due to the fact that they represent day-to-day routine behavioural practices. As these routine practices are socially and culturally structured, the identification of formation processes of plant remains can help identify social and cultural behaviour and changes therein.  相似文献   
24.
抗日战争时期,日本侵占了石景山炼铁厂(首钢前身),并改称石景山制铁所。日本统治下的石景山制铁所共生产生铁262617吨,这些都是靠掠夺中国的资源生产的。日本侵略者采取种种反动措施,企图把石景山制铁所建设成为他们在华北地区使用中国矿产资源生产钢铁的基地。这些措施包括:不断扩大石景山制铁所的生产规模;残酷剥削石景山制铁所的中国工人阶级;成立奴役中国工人及石景山地区人民的伪组织——爱护会;建立制铁所警备队。  相似文献   
25.
Recent multidisciplinary investigations document an independent emergence of agriculture at Kuk Swamp in the highlands of Papua New Guinea. In this paper we report preliminary usewear analysis and details of prehistoric use of stone tools for processing starchy food and other plants at Kuk Swamp. Morphological diagnostics for starch granules are reported for two potentially significant economic species, taro (Colocasia esculenta) and yam (Dioscorea sp.), following comparisons between prehistoric and botanical reference specimens. Usewear and residue analyses of starch granules indicate that both these species were processed on the wetland margin during the early and mid Holocene. We argue that processing of taro and yam commences by at least 10,200 calibrated years before present (cal BP), although the taro and yam starch granules do not permit us to distinguish between wild or cultivated forms. From at least 6950 to 6440 cal BP the processing of taro, yam and other plants indicates that they are likely to have been integrated into cultivation practices on the wetland edge.  相似文献   
26.
Analysis of starch granules, phytoliths, and plant macrofossils from archaeological features and carbonized food residue provides important new insight into the extent of prehistoric maize (Zea mays) consumption on the North American Great Plains. These data suggest that consumption of maize, and probably other cultigens, was widespread on the eastern Canadian Prairies between approximately AD 1000 and 1600. Domesticated plants may have been grown locally, acquired through trade, or transported into the region following dispersal of family groups from horticultural villages located elsewhere. However, the lack of strong artifactual evidence of gardening, and the small-scale nature of sites on the eastern Canadian Prairies indicate that local horticulture, if practiced, was non-intensive.  相似文献   
27.
This paper examines evidence for the origin of the tree Spondias mombin in Africa, where it is generally described as introduced from the Neotropics. Based on biogeographical, ecological, and historical evidence, this paper argues that the tree reached Africa via natural, long-distance dispersal, and should be considered an African native plant. The idea that it is introduced appeared in 1868, when it was a scientifically justifiable conclusion reflecting the limitations of nineteenth-century biogeographical knowledge. By the early twentieth century, representing Spondias mombin as a human introduction in Africa was no longer scientifically justifiable because of advances in knowledge of the African flora and plant dispersal ecology. Nonetheless, most authors continued to represent the tree as introduced, in part because such representation was consonant with dominant images of the African environment: (a) that the continent had suffered extensive deforestation in the recent past, and (b) that Africa's flora was depauperate in fruit trees prior to the coming of Europeans. Recent authors continue to describe Spondias mombin as introduced because they have not sufficiently considered the historic contexts of primary and secondary sources on Neotropical plant introductions in Africa. This paper concludes that the human role in creating the African portion of the trans-Atlantic tropical flora has been overemphasized. Natural plant dispersal across the Atlantic may be more frequent than generally accepted.  相似文献   
28.
Cobalt blue glass has long now been recognised as characterised by a distinct compositional signature within the typical compositional range of Late Bronze Age glass. More recently, a copper-rich variation of cobalt blue glass has been seen throughout Egypt and the Mycenaean world. This paper discusses and defines this glass type based on trace elemental data, examines whether this lighter-shaded cobalt blue glass is a natural or an anthropogenic variant of cobalt blue glass, and identifies its likely production in Egypt. It investigates the role of this type of glass, particularly with regard to the distribution pattern and the significance of its prevalence in the Mycenaean mainland and the Aegean.  相似文献   
29.
To continue to explore the impact of past human activity on the stable nitrogen isotope ratios of modern vegetation, we have measured the δ15N values of plants now growing on several ancient farmsteads in the Western Settlement of Norse Greenland. Although this new test area is some 400 km north and in a different ecoregion from the previous study area, the same isotopic effect was observed. A clear isotopic signature was found on the ancient farms which could be directly correlated to past activity areas; in particular, the infields. Further, the magnitude of the δ15N values was found to be similar between study areas, indicating the same interpretative framework can be applied in widely separate geographic regions. A first test of different plant species showed that although the magnitude differed greatly the same basic information was found for functionally different plants. These observations provide additional information to aid in future archaeological application of this newly observed phenomenon.  相似文献   
30.
A pile-dwelling settlement, dated to the final Bronze–early Iron Age (XII–XI century BC), was excavated at Stagno, near Leghorn (Tuscany, Italy). The site presented a well-preserved portion of the wooden foundation structure buried by sediments rich in plant remains: both wood and plant remains were subjected to archaeobotanical investigation. The ultimate goal was to improve our knowledge on agricultural economy and wood usage in Tuscany during the prehistoric ages. The results pointed to a farming system based on Triticum spp. (wheat), Hordeum spp. (barley) and Leguminosae cultivation in addition to the gathering of wild fruits, such as Corylus avellana, Cornus mas, Prunus spp., Vitis spp. Many of these plant remains are associated to a wetland context. Mesohygrophilous trees, such as deciduous Quercus, Ulmus minor, Fraxinus cf. excelsior, and Sorbus were used for the construction of the pile-dwelling structures; the choice of these plants indicates a good knowledge of the technological characteristics of timber.  相似文献   
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