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211.
The Etowah site is one of the larger and more famous Mississippian period mound centers in the American Southeast. Despite the fact that over a century of archaeological investigations have been conducted at the site, its history is not as well-understood as sequences of other major Mississippian centers like Moundville or Cahokia. This is because few attempts have been made to synthesize existing information and place the site in a broader social context. In this paper I review previous research at Etowah and present a reconstruction of the site's history as a chiefdom capital. In attempting to understand that sequence, I draw upon the distinctions made by dual-processual theory concerning the orientation of chiefdom political economies and how they vary. Both the specific history of Etowah and the parallels it shares with the sequences of other chiefdom capitals have important implications for understanding more generally the emergence and operation of ranked societies.  相似文献   
212.
As a direct consequence of exposure to microgravity, astronauts experience a set of physiological changes which can have serious medical implications when they return to earth. Most immediate and significant are the headward shift of body fluids and the removal of gravitational loading from bone and muscles, which lead to progressive changes in the cardiovascular and musculoskeletal systems. Cardiovascular adaptations result in an increased incidence of orthostatic intolerance (fainting) following flight, decreased cardiac output, and reduced capacity for exercise. Changes in the musculoskeletal system contribute significantly to impaired function experienced in the post-flight period. The underlying factor producing these changes is the absence of gravity, and countermeasures are therefore designed primarily to simulate earthlike movements, stresses, and system interactions. Exercise is one approach that has had wide operational use and acceptance in both the US and Russian space programmes, and it has enabled humans to stay relatively healthy in space for well over a year. Although it remains the most effective countermeasure currently available, significant physiological degradation still occurs. The development of other countermeasures will be necessary for missions of longer duration, for example for human exploration of Mars.  相似文献   
213.
The reader of Sermones Ⅱ who turns to Satire 6 fresh from Satires 1-5 cannot fail to be surprised. Up to this point in the collection we have grown accustomed to a speaker who is conspicuous by his virtual absence from his own work. The most distinctive feature of this new book of Sermones is, in fact, the virtual exclusion of Horace's own voice as he abdicates the satirical voice of Sermones Ⅰ to a range of other speakers in book II, presenting his material in an overtly dramatising form: either as monologue or diaiogue. Such remodelling of the form of satira is evident in the accelerating progress towards the dramatic form. in the sequence of five poems which opens Sermones II. In the programmatic satire which launches the collection, Horace, dissatisfied bv reaction to his .  相似文献   
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Adam G. Bumpus 《对极》2011,43(3):612-638
Abstract: This paper examines the socio‐natural relations inherent in the commodification of carbon reductions as they are generated in energy‐based carbon offset project activities, and abstracted to wider market systems. The ability to commodify carbon reductions takes place through a socionatural–technical complex that is defined by the material nature of technology's interaction with the atmosphere, local social processes and the evolving governing systems of carbon markets. Carbon is not unproblematically commodified: some projects and technologies allow a more cooperative commodification than others. The examples of a hydroelectricity plant and an improved cookstove project in Honduras are used as empirical case studies to illustrate the difficulties and opportunities associated with the relational aspects of carbon commodification. Drawing upon select literatures from post‐structural thought to complement the principal lens of a more structural, materiality of nature analysis, the paper also outlines the reasons why carbon offset reform is needed if offsets are to more progressively engage debates about climate mitigation and North–South development.  相似文献   
216.
This article investigates the role of power and ideology in the endogenous formation of policy networks. According to the Advocacy Coalition Framework (ACF), shared ideology (conceptualized as a system of policy‐relevant beliefs and values) is the primary driver of collaboration within policy subsystems. On the other hand, Resource Dependency Theory suggests that power‐seeking is an important rationale behind network structure, and that collaborative ties are formed primarily on the basis of perceived influence. Hypotheses are tested using a new method of egocentric network correlation, based on survey data of policy networks in five regional planning subsystems in California (N = 506). Results suggest that ideology is an important force behind network cohesion: Not only do policy elites systematically avoid networking with ideologically dissimilar actors but collaborative ties are also systematically formed among actors with shared beliefs. Power‐seeking does not operate on a network‐wide scale but may drive network formation among coalitions of ideologically similar agents.  相似文献   
217.
The paper presents an analysis of depositional sequences of landslide peat bog situated in the depressions developed within the landslide landforms Jesionowa in the Beskid Sądecki Mts. (Outer Carpathians). The peat bog, with depositional sequence 2.80 m long, started to form at the beginning of the Atlantic Phase ca. 6390–5910 cal BC. Palynological and lithological analyses as well as several (14) radiocarbon age determinations of different horizons in the sediments enabled the reconstruction of palaeoenvironmental changes during the Meso-and Neoholocene. The increase in climate humidity at the beginning of the Subboreal and Subatlantic Phases was observed as delivery of minerogenic material to the peat bog basin and formation of a mineral horizon and an illuvial level within the peat. The particularly intensive delivery of allochthonous material to the peat bog took place at the beginning of the Subboreal Phase and was the result of both significant humid climate and increased human impact (colonization of the Funnel Beaker Culture) in the landslide area. Similar influence of younger colonisations of landslide area (Przeworsk Culture and, later, Valachian colonisation) was also recorded within the deposits of peat bog (illuvial and mineral horizons) in the early Subatlantic Phase. Rejuvenation of the landslide zone and formation of the younger landslide were connected with the increase in climate humidity at the beginning of the Subboreal Phase. The peat bog deposits situated within this younger landslide, which are ca. 1.8 m thick, are significantly contaminated with mineral material.  相似文献   
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219.
As many new certification systems for commodities have been established over the past decade, scholars have devoted sustained attention to the ways that these multi‐stakeholder governance initiatives have transformed the industries in which they were launched. With a few notable exceptions, studies in this area have continued to focus on the development and impacts of new governance mechanisms, and on the sectoral or industrial changes that have ensued. In contrast to these ‘inside‐out’ perspectives on governance innovation and change, this article considers how two prominent yet relatively under‐studied commodity governance initiatives have been shaped by the broader political economic order in which they operate. To offer an ‘outside‐in’ account of the Better Cotton Initiative (BCI) and Bonsucro (formerly the Better Sugarcane Initiative), the article details recent changes in what the author terms the ‘world commodity order’, and situates the BCI and Bonsucro within this order. From this vantage point, the author ultimately makes two analytical claims: (i) that the world commodity order has not precluded the differential institutionalization of these initiatives; and (ii) that aspects of the order have circumscribed the potential of the BCI and Bonsucro to deliver pro‐poor business practices.  相似文献   
220.
The Roman and Byzantine monuments at Sabratha in northwest Libya represent cultural heritage of remarkable global significance. This report describes the weathering damage of calcarenites, the most dominant stone type used in the construction of monuments in the ancient city of Sabratha. Stone loss, particularly alveolar weathering, notching and breakout of compact stone fragments, dominates deterioration phenomena. Other weathering forms include stone detachment (granular disintegration into sand) and fractures. Most of the studied monuments are also severely affected by biodeterioration, due to microorganism colonization that appears as biofilm. Both the low durability of the calcarenites and the marine environment with characteristic humidity and salt-rich marine spray are the important factors contributing to stone weathering. The results obtained in this pilot study may be used as a guideline for future restoration works.  相似文献   
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