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151.
We investigated fossil tooth enamel of mammals and crocodiles from two Mio-Pliocene East-African formations (Lukeino and Mabaget Fms) using infrared spectroscopy and chemical and stable-isotope analyses. Infrared spectra indicate that the fossil enamel contains biological apatite (bioapatite), without significant secondary carbonate contaminations. Several empirical infrared indexes were used to analyze the crystal–chemical characteristics of enamel. Fossil enamel has less organic matter, water and structural carbonate of apatite than modern enamel with which it was compared. Fossil apatite has a better crystallinity than bioapatite. The calcium/phosphorus mass ratio and the fluorine content of fossil apatite show intermediate values between bioapatite and geological fluorapatite. The samples also display significant crystal-chemical variations, depending on the vertebrate group (mammals vs. reptiles) and the taphonomic context (Lukeino Fm vs. Mabaget Fm). In spite of these changes, no relationship was observed between the chemical contents (carbonate and fluorine) and the stable-isotope ratios of carbonate (δ13C and δ18O) in fossil enamel. Preservation of the palaeoenvironmental signals is strongly supported by the fact that the stable-isotope composition of the three investigated fossil mammalian taxa (deinotheres, equids and hippos) is consistent with their ecological features. For instance, typical C3- and C4-plant isotope compositions are reflected in the deinotheres and equids, respectively, and amphibious hippos display lower δ18O values than terrestrial herbivores, as expected. 相似文献
152.
Point Predictions and the Punctuated Equilibrium Theory: A Data Mining Approach—U.S. Nuclear Policy as Proof of Concept
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In Punctuated Equilibrium Theory (PET), information processing under the constraints of limited attention and bounded rationality leads to stick‐slip dynamics in policy outcomes. Empirical work in this field often focuses on the macro level. Using the case of nuclear energy policy in the United States as proof of concept, we demonstrate how decisive budget changes in a specific policy subsystem can be linked to attention of Congress and the president. We utilize a mixed‐methods data‐mining approach: Maximum likelihood estimation is used to analyze the distribution of the nuclear energy RD&D budget. Then attention data of both Congress and the president are structured by means of cluster analysis and principal component analysis. Finally, these data are used in a generalized linear model to predict specific budget shifts. The article is designed as a proof of concept: In the case of nuclear energy policy, we are able to predict budget shifts without violating the assumptions of PET. More importantly: we can demonstrate that attention is not only affecting the final policy outcome but also the corridor of the possible. 相似文献
153.
Uncarbonized Cucurbita pepo L. (squash) seed coats were recovered from the base of a fortification ditch in water-saturated contexts at the Hoxie Farm site (11CK4) in northeastern Illinois. A direct date on one specimen indicated association with the Huber phase occupation, or about 1600 A.D. Sizes were highly variable, suggesting the presence of two or more squash varieties. To explore that possibility, length and width measurements were obtained for 21 specimens. A simple hierarchical cluster analysis revealed the presence of three distinct seed size groups. The two smaller conform to sizes displayed by modern varieties of subspecies ovifera which is the type domesticated in North America. Sizes for the third group of large seeds fall outside the range of any modern subspecies ovifera and within the range for the Mexican domesticate subspecies pepo. Similar large sized seeds first appear in the archaeological record from the Midwest during the Late Mississippian times. The potential for long-term prehistoric cultivation of two distinct lineages in the Midwest, and problems inherent in the scenario are discussed. 相似文献
154.
The contemporary trend within natural resource governance sees a strong increase in collaborative management. A successful turnout of these arrangements is, however, dependent upon the formation and characteristics of advocacy coalitions. Uncovering the rationale determining coalitions is therefore a key undertaking in policy analysis and the advocacy coalition framework (ACF) has been widely applied for this purpose. This article aspires to test several important hypotheses regarding the nature of coordination networks and the formation of coalitions, treating the ACF both as an inspiration and as a framework in need of further refinement. This is done in the context of a complex and conflict‐ridden policy subsystem: the Swedish carnivore‐management subsystem. The results indicate, firstly, that perceived belief correspondence, and not perceived influence, is the driving mechanism behind coordination; and, secondly, that the catalog of beliefs shared by actors within a coalition is composed by policy core beliefs, in particular, with a more normative content, while no connection between deep core beliefs and coordination is found. 相似文献
155.
This article reflects upon recent interest in knowledge transfer from higher education to the creative industries, using the UK music industries as a case study. It suggests that traditional academic values of impartiality and concern with research methodology can come in to conflict with instrumentalist agendas that see research as valuable only insofar as it fits with pre‐existing worldviews and policy ends. In this setting, knowledge resistance is often more significant than knowledge transfer and may be expected to frustrate any attempts to have an ‘impact’. 相似文献
156.
Simon Coleman 《History & Anthropology》2013,24(4):275-290
This essay focuses on practices of representing the Holy Land, as performed by Protestant British travellers during the Victorian and immediately post-Victorian era. I argue that traveller-artists of the period, such as the Pre-Raphaelite William Holman Hunt, promoted a realist aesthetic that combined spiritual and ethnographic sensibilities in its depiction of sacred scenes. Similar concerns are evident in the writings of nineteenth-century pilgrims to Palestine, who wrestle with issues of "participation" and "observation" in relation to topographical and cultural landscapes that are exotic and yet already rendered partially familiar through biblical narrative. In conclusion, some parallels are drawn with aspects of representation and fieldwork evident among early anthropologists. 相似文献
157.
Simon Coleman 《History & Anthropology》2013,24(3):273-288
This article explores the “invention of tradition” thesis by examining the physical and ideological reconstruction, as well as the contemporary use, of the Christian pilgrimage site of Walsingham, in Norfolk, England. We argue that a focus on the actions and motivations of cultural élites encourages a one‐dimensional view of ritual and ignores how traditions may be transformed in the process of re‐enactment by other members of society. 相似文献
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