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81.
The recent application by Burton and Krinsley (1987) of back-scattered electron (BSE) petrography to obsidians from sources located in the south-western United States established that this method can effectively resolve and characterize included micro-crystalline phases that have proven difficult to analyse by optical thin-section microscopy. In the first extension of their original study, we have examined, using BSE petrography, obsidians from island sources located in the Mediterranean, including sources known to have been exploited in prehistory. Because of the kinetic contrasts on their crystallization, these microcrystalline phases reflect the magmatic history of the obsidian, providing information about superheating, supercooling, sub-solidus processes, and other phenomena. This information is of significance for the chemical analysis of Mediterranean obsidians and also as the basis for a powerful alternative to existing non-destructive analytical methods for the sourcing of archaeological and art-historical obsidian.  相似文献   
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Charles Edouard Brown-Séquard used observation of recovered patients and experimental animals to support his theory of cerebral localization. Recovery theories assume that the nervous system is composed of one organ or many, and that each organ has one function or many. From his own studies as well as others, Brown-Séquard concluded that the brain contained at least nine separate organs, each with a single distinct function, and that each organ is organized, not as a geographically isolated cluster of neurons, but as a widely disseminated network. According to his view, function is not uniformly distributed in an organ. Focal necrosis of part of an organ temporarily inhibits the action of distant, undamaged parts; resolution of this inhibition results in recovery. Using this theory of cerebral localization and recovery, Brown-Séquard practiced an early form of scientific neurology.  相似文献   
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Ancient mortars from northern Italy, dating from the fifth to the seventeenth century AD, were examined in order to formulate an hypothesis regarding the origin of the white lumps often observed in these mortars and in other samples of the same geographical provenance. Various characterization techniques were employed, including scanning electron microscopy, X-ray powder diffraction and Fourier transform infrared (FTIR) and micro-FTIR spectroscopy.  相似文献   
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Glow discharge optical emission spectrometry (GDOES) has been used for obtaining calibration curves for copper, tin, lead, silver, antimony, arsenic, zinc and iron from standards including copper-base alloys (Cu 61.33-99.95%) and from bronze Punic coins. The GDOES results were calibrated using atomic absorption spectroscopy with inductively coupled plasma atomization (ICPAAS) to analyse the standards and coins. For all these materials, the results show that via GDOES it is possible to obtain reliable and reproducible calibration curves for copper, tin, lead, zinc and iron with a linear behaviour as a function of the content. The quantitative GDOES and ICPAAS data for the coins have been also compared with those obtained via X-ray fluorescence (XRF) and it is shown that GDOES, ICPAAS and XRF agree well with one another considering that the bronze coins are inhomogeneous to some degree. As an example of GDOES analytical features, a depth concentration profile through a thin bronze patina is shown and briefly discussed.  相似文献   
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Ceramic vessels from Later Stone Age sites in the Seacow river valley, South Africa, were heavily tempered with C4 grasses. However, most δ13C values of the temper fall between the known δ13C ranges for C4 and C3 grasses. Among possible C3 additives that could skew the signal, ground bone, animal dung, alpine grass, Karoo scrub ash, and humic acid contamination are eliminated. The sherd surfaces yield fatty chars with C3-like values. Although these are not enough to account for all the skewing, they represent only the final cooking event. They were preceded by many such events in which fat was absorbed into the C4 grass then charred to soot by later periods in the fire. Thus organic carbon with the isotope composition of the fat built up while the vessel remained in use.  相似文献   
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The characterization of various samples of white marble from the archaeological site of Tharros (Sardinia) is the starting point for the reexamination of the capabilities of electron spin resonance (ESR) spectroscopy as a tool for identifying the quarries of origin of ancient marble artefacts. Existing methods and data bases are employed for the assignment of our samples, but also reviewed to see if a more extensive use of the technique is feasible. It turns out that ESR spectroscopy, coupled with other available methods, may readily provide valuable information, often yielding the final answer to the problem of marble provenance. However, it is also clear that much work has still to be done to standardize the data collection and analysis procedures and to expand the available data base.  相似文献   
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The special number of the Canadian Geographer devoted to West Edmonton Mall raises important questions, notably that of the relative status, as values, of work (seen historically as fundamental to our culture), and of leisure, perceived, albeit controversially, as being embodied in wem. In preparing to present my principal thesis, I review recent reinterpretations of human behaviour advanced by workers in the fields of symbolic interaction and the sociology of knowledge. These schools ha ve given rise to the concept of, though not the term, functional religion. The meaning of this concept is close to that of ideology; a comparative analysis of the two terms justifies using the former. A survey of recent work by geographers who approach religion from a functional point of view closes the second part of the paper. In the course of this review the relative status of work and leisure emerges as a significant issue. The view of leisure as a norm presented in the third part of the paper is that advocated by Pieper, Huizinga, and de Grazia. They argue that the Classical view, according to which human life finds its meaning in activities that are carried on for their own sake (e.g., games), rather than in those pursued for the material rewards they offer, is correct. Following their lead, and in opposition to both Marxists and Liberals, I argue that the adoption of leisure as a fundamental value would provide a more satisfactory foundation for our culture than work has to this point. Le numéro spécial du Géographe canadien consacréà?étude du West Edmonton Mall soulève plusieurs questions importantes, notamment celle du statut relatif, comme valeur, du travail (valeur-clé historiquement dans notre culture) et du loisir, valeurs incarnées, bien que de façon controversées, dans le WEM. Pour établir les bases de la thèse principale, on examine les réinterprétations récentes du comportement hurnain avancées, dans les sciences humaines, par des chercheurs travaillant dans les domaines de ?interaction symbolique et la sociologie du savoir. Ces écoles ont engendré le concept, sinon le terme, de la religion fonctionelle. Le sens de ce terme est proche de celui de ?idéologie; une analyse comparative des deux termes justifie ?emploi du premier. Pour conclure la deuxièrne partie de ce mémoire, on passe en revue quelques écrits récents par des géographes qui abordent la religion ?un point de vue fonctionnel. De cet examen il ressort que le statut relative du travail et du loisir est ?une importance capitale. Dans la troisième partie, on présente une perspective sur le loisir qui est proche de celle qu'avancent Pieper, Huizinga, et de Grazia. Ceux-cisupportent la position des auteurs classiques, selon qui la vie humaine trouve sa signification dans les activités entreprises pour ellesměmes (par exemple, les jeux) plutǒt que pour le gain matériel. Appuyant leur argument, et m'opposant à celui des marxistes et des libéraux, je prétends que ?adoption du loisir comme vaieur fondamentale fournirait une meilleure assise à notre culture que celle offerte jusqu'ici par le travail.  相似文献   
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