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61.
  总被引:1,自引:0,他引:1  
Contemporary cities in East Central Europe (ECE) represent a hybrid type of urban development which is still generally considered to be a special case and is only exceptionally referred to in the recently intensified debate over the European city. Our paper argues that such exclusion is short‐sighted because ECE cities face structural problems similar to those of their Western pendants. Therefore, the contextual frame of urban research needs to be widened and can no longer be restricted to post‐socialist transition. In this regard, one of the main challenges for future urban development will be the consequences of demographic change. Ageing, new patterns of fertility behaviour and more diversified household structures in line with the Second Demographic Transition (SDT) will have significant implications for urban structures and housing markets, as already known for Western Europe. The purpose of this paper is to work out new questions and hypotheses for future urban research with special respect to Polish and Czech cities. Besides West European experience, recent developments in eastern Germany are taken as a frame of reference, assuming that this specific transition case may, in many respects, be regarded as a forerunner for similar developments in its neighbouring countries.  相似文献   
62.
    
Anatomically preserved mature stems of late Middle Triassic corystosperms from the Paramillo Formation of Argentina are described and assigned to Cuneumxylon spallettii gen. nov. et sp. nov. The silicified specimens show features of the pith, primary xylem and successive rings of secondary xylem and phloem. The most striking characteristic is the anomalous secondary growth, represented by secondary xylem bounded by arcs of secondary phloem probably derived from successive repositioned cambia. Cuneumxylon has two kinds of unusual centrifugal secondary growth. The first shows unequal activity of different portions of the cambium on the circumference of the axes; the consequent restriction of cambial activity to certain restricted areas develops wedged stems, which often split. The second produces polyxylic stems following supernumerary cambial activity. As in extant plants growing in arid regions, the included phloem and the associated parenchyma may have had functional value avoiding desiccation of the outer tissues of the stem during droughts. Anatomical features of other Corystospermaceae were used to determine systematic affinities and to establish relationships among medullosans, corystosperms and cycads.  相似文献   
63.
    
Comparisons of conodont and trilobite communities from the Arenig-Llanvirn of northern Spitsbergen show that both groups were influenced by the same environmental factors, related to a shallow to deep water profile at the western edge of the proto-Atlantic Ocean (Iapetus). The majority of both conodonts and trilobites had benthic or nektobenthic habits; a few genera of both groups were pelagic. Temperature was a major influence on the distribution of conodonts; similar genera could occur on both sides of ancient oceans (e.g. Iapetus) given the same temperature regime.  相似文献   
64.
    
The Danish-Norwegian colony of Tranquebar in south-east India is a little explored case of science and ‘patriotic enlightenment’ in the colonial world of the 18th and early 19th centuries. In the period 1768–1813, Tranquebar emerged as a local south Indian hub of science and improvement. The symbol of this development was the establishment of the Tranquebarian Society, the third learned society east of the Cape of Good Hope. The article examines the unique assemblage of scientific networks, people, instruments, institutions, and ideas of local and global origin that converged in Tranquebar, and it investigates the fusion of local problems and radical ideas of enlightenment, education, and improvement that united government, mission, and merchants in Tranquebar in the quest for ‘useful knowledge’.  相似文献   
65.
    
Abstract

Before timber and stone houses were introduced to northern regions, varieties of turf houses were the most commonly used architecture. These houses had a wooden structure encapsulated in a shell constructed of grass turf. The different ethnic groups of the north built their houses in different styles and constructions, but the general principle was the same. The Norse of North Norway and also on the North Atlantic islands had a tendency to build their houses on top of the ruins of previous houses. After a few centuries this arrangement produced a settlement mound of highly organic soil. In the research literature, both the turf architecture and the settlement mounds have been described as adaptations to and a function of marginality and lack of timber. This paper reports an effort to test the idea that turf houses on top of settlement mounds may have been a finely tuned ecological system that made use of the capacity of organic soil to produce heat.  相似文献   
66.
    
Fusulinoideans from the Metadoliolina dutkevitchi-Monodiexodina sutchanica Zone of the lower part of the Chandalaz Formation in the Senkina Shapka section in South Primorye, Far East Russia, are described. The fusulinoidean zone is assigned to the early Midian (=Capitanian: late Middle Permian) based mainly on the morphologie and biostratigraphic characteristics of Metadoliolina dutkevitchi. Previously, a Midian age has been established for the Metadoliolina dutkevitchi-Monodiexodina sutchanica Zone by the coexistence of Lepidolina species. However, the occurrence of Lepidolina with the two zonal species in this area has not been verified by the illustration of Lepidolina specimens. We examined a fusulinoidean-bearing sample from the Metadoliolina dutkevitchi-Monodiexodina sutchanica Zone, and three fusulinoidean species, Monodiexodina sutchanica, Pseudofusulina sp. and Metadoliolina dutkevitchi, are de-scribed and illustrated.  相似文献   
67.
    
QIAO, X., SHIH, C.K. & REN, D., December 2012. Two new Middle Jurassic species of orthophlebiids (Insecta: Mecoptera) from Inner Mongolia, China. Alcheringa 36, 467–472. ISSN 0311-5518.

Two new species of the extinct family Orthophlebiidae, Orthophlebia nervulosa sp. nov. and Orthophlebia stigmosa sp. nov., are described and illustrated. These well-preserved specimens were collected from the Middle Jurassic Jiulongshan Formation near Daohugou Village, Inner Mongolia, China. Morphological characters shown in these well-preserved specimens highlight the diversity of orthophlebiids during the Middle Jurassic and provide data for future phylogenetic studies of orthophlebiids.  相似文献   
68.
    
The word ‘stromatolite’ should only be applied to organosedimentary structures predominantly accreted by sediment trapping, binding and/or in situ precipitation as a result of the growth and metabolic activities of benthic, principally prokaryotic, micro-organisms. Structures of uncertain origin that resemble stromatolites should be called ‘stromatoloids’. This cautious approach would eliminate the currently common assumption that structures with mesoscopic morphological similarities to microbially accreted sedimentary structures must be biogenic, a misconception that hampers investigations into the antiquity of life.

A hierarchical series of meso- and microstructural attributes of stromatolites can be used to assign gradually increasing probabilities of biogenicity to stromatoloids. This method is particularly useful for interpreting ancient noncolumnar stromatoloids with poor microstructural preservation. In a range of Early Archaean pseudocolumnar, nodular and stratiform stromatoloids from North Pole studied using this method, none could be proved to be stromatolites and only a few are probable or possible stromatolites. As these stromatoloids closely resemble previously reported structures from North Pole interpreted as stromatolites, we consider that the evidence for the existence of life c. 3500 my ago at North Pole is less definitive than previously supposed.  相似文献   
69.
ABSTRACT

The context and conditions under which early modern Europeans created images and maps that blended Asian and American geographies have recently received the attention of scholars. In this article I explore an example of this practice in the Chilean Jesuit Alonso de Ovalle’s mapping of Asian spices as it affected the southern region of his Tabula geographica regni Chile (Rome, 1646). I examine Ovalle’s inclusion of cinnamon and pepper in the Patagonian landscape as a persuasive allusion to the crucial role of the Strait of Magellan in his proposed revision of the trade route of the Spanish galleons.  相似文献   
70.
The argali (Ovis ammon antiqua) assemblages from the Middle Pleistocene site of the Caune de l'Arago (Tautavel, southern France) were studied in terms of zooarchaeology and taphonomy. It is possible to discern palaeobiological information lost during fossilisation, as well as the palaeoethology of the bone collector, by the observation of taphonomic details preserved on the bone assemblages. The observations leave no doubt that both humans and carnivores were involved in the accumulation of argali carcasses in the cave. In some assemblages, the type of bones found in articulation and the gnawing marks observed are characteristic of carnivores. In other levels, the intense fracturing of the major limb bones in relation to their marrow content and mineral density, and butchering marks found on specimens in the earlier levels, are in favour of human accumulation, the modalities of which are discussed. The results suggest that the degree of carnivore activity seems to have been higher in levels M, N and O than in level F. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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