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61.
62.
El Mirón is a large cave in the Cantabrian Cordillera of northern Spain that presents a long archaeostratigraphic sequence radiocarbon-dated by over 60 assays to between 41,000 and 2000 BP. The sediments, collected from four areas within the cave and sieved-washed with fine wire meshes, contain microvertebrate remains of fish, frogs, lizards, birds and mammals, of which the latter are most abundant. Preliminary taphonomic analysis suggests that the microvertebrates were naturally collected by owls and (less) small carnivores. Small mammal assemblages are useful for palaeoenvironmental reconstruction because they are linked to particular habitats and are sensitive to environmental changes. The small mammals from El Mirón are ideal for this because sample sizes are large, bone preservation is good, and the stratigraphic sequence is long. In this paper we reconstruct the late Quaternary environments in the Cantabrian region of Spain using small-mammal assemblages from El Mirón Cave. On the basis of the ecologic adaptations of this suite of fauna, the majority still extant, we have identified seven habitat types, which are plotted through time. The evolution of the small mammal assemblages at El Mirón reveals seven major climatic shifts that correspond closely to the climatic changes recognized in the Iberian Peninsula during the last 41 kyr.  相似文献   
63.
The comparative study of sedimentary fabrics in relation to archaeological fabrics in various levels of the sites of Cova Gran de Santa Linya (Middle and Early Upper Palaeolithic) and the Roca dels Bous (Middle Palaeolithic) has made it possible to analyse the formation dynamics of the deposits and determine the extent of disturbance of the archaeological levels by natural processes. To achieve this, diagrams and two- and three-dimensional indices were calculated from the azimuth and dip angle of natural clasts and artefacts. The results indicate that the sedimentary levels were formed mainly by planar fabric shape gravitational processes (low depositional angles), which differ notably from the archaeological fabrics they contain, characterised by a greater degree of isotropy. This difference in the fabrics would reflect human activity and indicates that the archaeological levels both in Cova Gran and Roca dels Bous have not been subject to significant natural modifications, and are preserved in situ.  相似文献   
64.
This article comments upon the situation of sprawl in Spain and Madrid, especially residential sprawl. It does not appear to be a serious problem due to its low starting point, but artificial surface and residential sprawl is growing rapidly. For that reason, it may be an issue in the future. Between 2000 and 2006, urban residential land use grew 0.4% in Spain and 0.2% in Europe per year, land use of industrial and commercial areas grew 2.3% in Spain and 0.4% in Europe and total artificial surface grew 2.7% in Spain and 0.6% in Europe (EEA, 2010). Further, we will study the legislation on maximum and minimum urban density in Spain. The highest maximum urban density is established by the Basque Country, with 230 dwellings per hectare, and the highest minimum urban density is established by Catalonia, with 50 dwellings per hectare. In both cases, it is applied to only certain types of territories. Finally, we will analyse what happens in the Region of Madrid in relation to sprawl. It has very similar patterns compared with the rest of Spain, although more pronounced.  相似文献   
65.
ABSTRACT This paper delves into the factors, which determine the attractiveness of regions in Europe for migrants. Contrary to the literature on the United States, which has increasingly focused on the role of amenities, existing research in Europe tends to highlight the predominance of economic conditions as the main drivers of migration. Differentiating between economic, sociodemographic and amenity‐related territorial features, we examine the appeal of various regional characteristics for migrants by analyzing net migration data for 133 European regions between 1990 and 2006. Our results show that, in addition to economic, human capital‐related and demographic aspects, network effects and—in contrast to existing literature—different types of regional amenities exert an important influence on the relative attractiveness of sub‐national territories across the European Union. Our findings therefore indicate that locational choices in Europe may be much more similar to place‐based preferences in the United States than originally thought.  相似文献   
66.
67.
This paper argues that observing neighborhood movements through the lens of territorial state restructuring holds theoretical promise. Contemporary struggles over municipal decentralization need to be located within broader state re-scaling processes. Seeking to contribute a Latin American perspective to the largely Anglo-American field of urban neoliberalization research, this study engages with the emergence of local autonomy claims in Buenos Aires, Argentina. Middle-class activists and organizations advanced such claims against the background of thorough transnationalism, in what may be interpreted as a localist political reaction to the socio-spatial consequences of urban and state restructuring. Field evidence is used to assess the ultimate political efficacy and democratic implications of their political agency, particularly in what concerns municipal decentralization. It is argued that curtailing the empowerment of barrio districts were the following conditions: mayoral opposition to communal reforms; ongoing cross-scalar tensions between the city and national government; and the barrio-centric issue framings of activists, which hampered social recruitment in an increasingly heterogeneous and transnationalized urban space.  相似文献   
68.
Bones treated at low temperature do not present major modifications although, macroscopically, boiled bones may be distinguished from unboiled ones as they are smoother, lighter and more transparent. Such observations should correspond to textural modifications at a nanometric level and should depend on boiling time. In this study, contemporary human bones, boiled during various time intervals, were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and nitrogen adsorption (BET). The results were used to estimate the boiling time in four archaeological samples (Neolithic bones from Malalmuerzo cave, Spain). It is concluded, comparing Neolithic bones to contemporary ones and from the textural characterization at a nanometrical level, that two of the archaeological bones were boiled and that they were boiled for less than 6 hours.  相似文献   
69.
We present a scheme to modify empirical Green's functions by attenuation considering: (1) geometrical spreading; (2) decay in high frequency; (3) regional attenuation; and (4) phase of the signal. The accelerograms computed with the proposed simulation method are compared, in time and frequency domains, with strong ground motions from subduction and intermediate-depth earthquakes recorded in Mexico. It is shown that this simple empirical Green's functions technique can synthesize both the shape and amplitude of the response spectra in the site, considering a postulated seismic source located at different distances from the original one.  相似文献   
70.
This paper looks at the St Kitts and Nevis Mummies' plays as published in Folklore by Roger Abrahams (1968). It demonstrates that the texts were originally taken from a play published by the Victorian children's author Mrs J.H. Ewing. This play appeared in several editions, most notably in two series issued by the Society for Promoting Christian Knowledge. Mrs Ewing's text was itself compiled from three northern English chapbook texts and a version from Silverton, Devon. The relative contribution of these texts to Mrs Ewing's play, and the way she put them together, are both explored.  相似文献   
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