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Results suggest that ESR studies of Mn+2 in marble can provide an excellent discriminator for the determination of marble provenance. In comparison with other methods of quantitative analysis for manganese such as AA or NAA, the ESR method determines only Mn+2 rather than total Mn, is inexpensive and rapid with no chemical preparation required, and does not consume the sample. 相似文献
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Gas liquid chromatography was used to analyse residues adhering to the inside of excavated potsherds from dated South African sites. The results suggested marine animal fat, possibly seal, had been cooked in the vessels. Fat of modern seals was baked and also analysed as a control sample. This gave similar results. The importance of seals in the prehistoric diet of the Southwestern Cape is supported by a large number of seal bones in the associated faunal material. 相似文献
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Economic geography has undergone a number of paradigm shifts since the Von Thunen model was at the peak of its popularity in the 1960s and 1970s. This study examines the cost of moving wheat from farm to ship in South Australia and constructs a transport-cost surface for the season 1991/92. Transport costs still exert a very important influence on farm returns and land values. Governments and other authorities, when making decisions in the name of rationalisation, or microeconomic reform, should examine very carefully the spatial consequences of their actions. In the short-run at least, the farmer's world is very much a normative and partial equilibrium one. At least in respect of a significant Australian agricultural enterprise, normative and partial equilibrium models should not be seen as obsolete. 相似文献
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RHIANNON E. STEVENS EMMA LIGHTFOOT JULIE HAMILTON BARRY CUNLIFFE ROBERT E.M. HEDGES 《Oxford Journal of Archaeology》2010,29(4):407-428
Carbon and nitrogen isotope analyses were performed on human and animal bones recovered from pits within Danebury Iron Age hillfort. All results are within the range expected for European Holocene specimens and are similar to those from other Iron Age sites in central southern Britain. Our results indicate that the human diet included a significant amount of animal protein (meat and/or dairy products) consumed on a regular basis, but do not preclude a diet based heavily on cereal consumption. In comparison with the extensive heterogeneity visible in the animal isotope values, the homogeneity of the human values is rather striking. This may be a reflection of the much slower turnover rate of adult human collagen and may also indicate that the humans consumed a much greater variety of food than the fauna (thus averaging many isotopic sources). This is consistent with the role of hillforts as central places and locations for food distribution and exchange. 相似文献
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Travertine was one of ancient Egypt's most popular ornamental stones. Upon prolonged exposure to sunlight, the rock's translucent brownish calcite is bleached to nearly white. Ultraviolet and gamma irradiation experiments were undertaken to investigate the source of the brownish colour and the process by which it fades. It was found that the coloration results from the activation of colour centres by natural radioactivity within the rock, and that these colour centres are deactivated by the ultraviolet component of sunlight. The results also demonstrate that the original brownish colour of sun‐bleached, travertine objects can be restored by artificial gamma irradiation. 相似文献
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The idea of non‐alignment has remained a central component of Indian identity in global politics that is manifest in continuities: since independence in 1947 India has been in pursuit of strategic autonomy, a quest that in practice has led to semi‐alliances fashioned under the cover of non‐alignment and shaped by regional dynamics. In this setting, the rise of China now raises an interesting conundrum for Indian policy‐makers as New Delhi seeks to balance the benefits and risks of an increasingly assertive neighbour and a network of alliances with like‐minded countries. This article approaches this enigma by delineating continuities of non‐alignment from the early roots of the policy, through the Cold War‐era and into the modern‐day international system. Though domestic factors have had a significant influence on the trajectory of Indian foreign policy, the continuities of non‐alignment have prevailed through changes in leadership and domestic vicissitudes. By exploring the foundation of non‐alignment and how India has operationalized the policy, this article maintains that to some extent continuity will persist: India will likely continue its rhetoric in favour of strategic autonomy while moving closer to the West and its allies in practice. Yet in order to effectively balance China's growing influence, India will need to be more assertive in building these alliances, as the success of its modern‐day pursuit of strategic autonomy may well rest on a strong foundation of strategic partnerships. The coming to office in May 2014 of the National Democratic Alliance government led by Narendra Modi has signalled a move away from even the rhetoric of non‐alignment, with significant implications for the future of Indian foreign policy. 相似文献