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Jennifer M. Jones 《History of European Ideas》2013,39(3):432-433
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The effect of charring and burial on the biochemical composition of cereal grains: investigating the integrity of archaeological plant material 总被引:1,自引:0,他引:1
A.K. Styring H. Manning R.A. Fraser M. Wallace G. Jones M. Charles T.H.E. Heaton A. Bogaard R.P. Evershed 《Journal of archaeological science》2013
Stable isotope analysis of charred archaeobotanical cereal grains has the potential to provide direct evidence of crop growing conditions in the past and to refine palaeodietary predictions. If isotope values of archaeobotanical material are to be considered robust, it is necessary to characterise the compositional changes associated with their charring and burial. This study used a suite of analytical techniques, including FT-IR and solid state 13C NMR, to characterise changes in the biochemical composition of modern einkorn grains with heating at 230 °C for 2 h, 4 h, 8 h and 24 h, encompassing conditions that replicate their undistorted ancient counterparts. The biochemical composition of archaeobotanical charred einkorn grains was also investigated by FT-IR and solid state 13C NMR in order to assess the changes in composition which occur during burial. Results of FT-IR and solid-state 13C NMR show that heating of modern einkorn grains resulted in Maillard reactions between cereal proteins and starch, forming high molecular weight melanoidins, which contain both alkyl and aromatic carbon. Loss of low molecular weight carbon and nitrogen-containing volatiles resulted in a slight but non-systematic increase in the δ13C values and a systematic increase of 0.8‰ in the δ15N values of the charred einkorn grains. Solid-state 13C NMR shows that the ancient charred einkorn grains consisted entirely of aromatic carbon and retained a similar proportion of nitrogen to their modern 24 h charred counterparts, despite a significantly lower concentration of amino acids. This indicates that the amino acid nitrogen in the ancient charred grains was retained in the stable melanoidins whose polymeric structure makes them resistant to subsequent degradation. 相似文献
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This article provides an indictment of the study of South-East Asian international relations by confronting head-on the problems that have arisen within this field, in particular the way in which Western academics ended up colluding with deeply illiberal regimes in the area, which excluded dissenting opinions, often by deliberately denouncing these opinions as 'polemical'. This study uses the discipline of Sovietology to explore the reasons why South-East Asian studies developed into a closed community of scholarship, often hostile to dissenting viewpoints. The disciplines bear comparison because they both manifestly failed to predict the cataclysms that befell their respective areas of study. The analysis identifies similarities in the way in which the two disciplines seemed to ignore sceptical voices and evolved a shared belief in 'system stability'. As a result, both Soviet studies and the study of South-East Asian international relations developed serious methodological flaws. However, this study argues that South-East Asian studies suffered even more severe disciplinary shortcomings than its Sovietological counterpart because the academic space was further de-intellectualized by the pervasive influence of the authoritarian South-East Asian developmental state which blurred the distinction between scholarship and bureaucracy and which succeeded in co-opting Western academics. The result was to create a field of study that promulgated the tyranny of the single truth, which erroneously perceived South-East Asia as a region of domestic tranquillity and regional order. What, in fact, emerged was an intellectual culture of self-censorship that kept South-East Asian studies within tacit, self-regulated boundaries. 相似文献
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Donald W. Jones 《Journal of regional science》1988,28(3):317-327
ABSTRACT. Previous work has developed a method for studying noninfinitesimal operational units, called “plantations,” with the Thüen model. In that model, increasing returns to scale generate large operational units, but the potential market power conferred by the scale economies is sidestepped as an issue. The present work introduces finite supply elasticities and examines their locational impacts. The profit-maximizing monopsonistic plantation is smaller, and the shipment distance for its processed output is shorter, than for a comparable competitive plantation. The present approach does not involve spatial competition strategies. 相似文献