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41.
Natural, technical and social factors led to the use of a wide range of rocks for the production of macrolithic artifacts during the later prehistory. In the case of some artifact types, such as the grinding stones, rocks with very different petrographic qualities appear. Analysis of the material behavior, as developed by material sciences, provides a tool which allows the translation of these petrographic characteristics into mechanical properties. Experiments with a group of rocks subjected to different forms of abrasion in industrial machines allow an evaluation of the adjustment between the mechanical properties of the rock and the functions for which they were chosen by prehistoric societies. Finally, the understanding of the mechanical properties of the raw materials together with their forms of exploitation, distribution and use allows the designation of social and economic meaning to the production systems linked to the macrolithic tools.  相似文献   
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In 1987, given the importance and complexity of the correct recovery and conservation procedures for underwater archaeological finds, an Underwater Archaeological Operations Unit was set up within the Italian Central Institute for Restoration. This Unit is made up of archaeologists, conservators, biologists and chemists, all of whom are underwater experts. It provides consultancy services and scientific and technical assistance for problems relating to the recovery, conservation, protection, and restoration of underwater archaeological heritage at the request of the Archaeological Superintendents. Great attention is paid to the professional training of underwater conservators. Specialized courses in the conservation of materials of underwater provenance are organized as part of its programme. This paper illustrates some of the main initiatives both in the restoration of archaeological objects and in training, in which the Institute has been involved, since the Underwater Unit was created.  相似文献   
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Recent excavations at Palù di Livenza (northeastern Italy) revealed a multiphase Neolithic pile dwelling dated between ca. 4,300/4200 and 3,600 cal BC. Three lumps with teeth imprints and a larger amorphous piece from the Late Neolithic layers have been studied by X-ray computed micro-tomography (microCT) and synchrotron Fourier-transform infrared spectroscopy (FTIR). FTIR spectra match well that of birch bark tar and microCT of the larger piece has revealed a rolled-up structure likely corresponding to bark rolls. The lumps of birch pitch were probably chewed to soften the tar prior to be used as hafting adhesive or therapeutic substance. The rolled-up inner structure of the larger piece and the remains of birch bark tar and abundant charcoals on its surface suggest it probably corresponds to a rare waste product from allothermic tar production.  相似文献   
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We analyze the firm-level labor productivity growth returns of social capital—defined as a synthetic measure of “generalized trust,” “active participation,” and “social norms”—using a large sample of manufacturing firms in France, Germany, Italy, Portugal, and Spain. We find that firms' labor productivity growth is higher in areas with a better social capital endowment. The positive returns of social capital are, nevertheless, unevenly distributed across firms, with smaller, less productive, less capital-endowed, and low-tech firms benefitting the most from operating in strong social capital ecosystems.  相似文献   
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We report a successful extraction and sequencing of ancient DNA from carbonized rice grains (Oryza sativa) from six archaeological sites, including two from India and four from Thailand, ranging in age from ca. 2500 to 1500 BP. In total, 221 archaeological grains were processed by PCR amplification and primary-targeted fragments were sequenced for comparison with modern sequences generated from 112 modern rice populations, including crop and wild varieties. Our results include the genetic sequences from both the chloroplast and the nuclear genomes, based on four markers from the chloroplast and six from the nuclear genome. These markers allow differentiation of indica rice from japonica rice, the two major subspecies of Asian rice (O. sativa) considered to have separate geographical origins. One nuclear marker differentiates tropical and temperate forms of subspecies japonica. Other markers relate to phenotypic variation selected for under domestication, such as non-shattering, grain stickiness (waxy starch) and pericarp colour. Recovery and identification of sequences from nuclear markers was generally poor, whereas recovery of chloroplast sequences was successful, with at least one of four markers recovered in 61 % of archaeological grains. This allowed for successful differentiation of indica or japonica subspecies variety, with japonica identified in all the Thai material and a mixture of indica and japonica chloroplasts in the two Indian assemblages. Rice subspecies was also assessed through conventional archaeobotanical methods relying on grain metrics, based on measurements from 13 modern populations and 499 archaeological grains. Grain metrics also suggest a predominance of japonica-type grains in the Southeast Asian sites and a mixture of japonica and indica in the Indian sites with indica in the minority. The similar results of grain metrics and ancient DNA (aDNA) affirm that grain measurements have some degree of reliability in rice subspecies identification. The study also highlights the great potential of ancient DNA recovery from archaeological rice. The data generated in the present study adds support to the model of rice evolution that includes hybridization between japonica and proto-indica.  相似文献   
47.
The work focuses on the potential of structural and chemical examinations by scanning electron microscopy based methods for archaeometric studies on ceramics. Achieved by a single preparation technique (polished block sections), the feasibility and benefits of electron backscatter diffraction are demonstrated as case studies using polychrome examples of pre‐Columbian pottery (Wari, Moche and Cajamarca). Elemental and phase maps allow for separate consideration of clay and temper. Identification of mineral phases and intergrowths of temper particles provide information for clarifying clay procurement and firing techniques with respect to local versus non‐local pottery to enlighten trade relations, technological transfer and shared heritage of pre‐Columbian cultures.  相似文献   
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This paper investigates how the overall impact of the European Cohesion Policy depends on the composition of the regional investment in Hard (infrastructure) and Soft (business and technical support) projects. The study employs a generalized propensity score (GPS) analysis in a multidimensional treatment context. In particular, the two dimensions considered are given by the Hard and Soft investments. The GPS estimation is based on a set of relevant idiosyncratic features of the regions. The second step estimates a dose–response function in a two-dimensional setting. The results confirm the existence of nonlinearities in the effect of different amounts of funds, but more importantly, show a degree of complementarity between Hard and Soft investment and that for policymakers, it is crucial to exploit such features to achieve more significant impact. The EU's more developed regions could have achieved a doubled GDP p.c. growth rate by pursuing a policy mix where Hard investments are reduced in favor of Soft investments. This improvement is comparable to the one obtained by at least doubling the available resources. The findings add to the evidence collected on the impact of the Cohesion Policy, suggesting a shift of the debate from the quantity to the quality of the expenditure pursued under the umbrella of territorial policies.  相似文献   
50.
Here we examine patterns in stone tool technology among Mesolithic, Neolithic and Iron Age localities in the Sanganakallu–Kupgal site complex, Bellary District, Karnataka, South India. Statistical tests are used to compare proportions of raw materials and artefact types, and to compare central tendencies in metric variables taken on flakes and tools. Lithic-related findings support the inference of at least two distinct technological and economic groups at Sanganakallu–Kupgal, a microlith-focused foraging society on the one hand, and on the other, an agricultural society whose lithic technologies centred upon the production of pressure bladelets and dolerite edge-ground axes. Evidence for continuity in lithic technological processes through time may reflect indigenous processes of development, and a degree of continuity from the Mesolithic through to the Neolithic period. Lithic production appears to have become a specialised and spatially segregated activity by the terminal Neolithic and early Iron Age, supporting suggestions for the emergence of an increasingly complex economy and political hierarchy.  相似文献   
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