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901.
Important ancient Roman chemical processes involved ammonium, especially fulling. Ammonium accumulates in decaying urine as a dilute chemical agent but is unfortunately present alongside substances which interfere with later processes, such as malodorous organic compounds and bacterial debris. This paper demonstrates how ancients may have obtained concentrated material by crystallization of ammonium salts and purification to a high degree by simple decanting, which uses only those resources available in the first century AD. It is proposed that first century Romans used decayed urine to produce the urine powder “Struvite”, a pure and concentrated form of ammonium. Possession of concentrated ammonium allows for a very wide range of chemical processes but only the very simplest example is presented in this paper; smelling salts.  相似文献   
902.
Michael H. Finewood 《对极》2016,48(4):1000-1021
This paper explores Pittsburgh's water governance to consider the way divergent approaches to urban stormwater management reproduce existing urban metabolisms and belie more radical possibilities for the urban hydro‐social cycle. Federal action has forced municipalities in the Pittsburgh metropolitan region to make changes to its urban water systems and develop a plan to comply with water quality regulations. Within Pittsburgh's water governance debates, compliance centers on various sets of technological strategies for defining and solving purportedly wicked urban environmental problems. Urban political ecology, here, is used to deconstruct the tensions and convergences between these different stormwater governance strategies. I argue that green infrastructure approaches (whose intentions are to expand practice and participation) are framed by dominant grey epistemological approaches. In this view, alternative and creative forms of greening the city may not necessarily represent a more democratic process, but instead reproduce uneven urban landscapes under greener cover.  相似文献   
903.
904.
This paper examines the possibilities of creating quantified models of past human activities in both time and space. The study area lies in the south‐eastern Czech Republic and western Slovakia. The spatio‐temporal model of behavioural categories was calculated with the help of Monte Carlo simulations and statistical testing. One of the main advantages of our approach is that it admits the probabilistic nature of input data, quantifies them and provides probabilistic results comparable with other proxies. It also presents a less biased way of how archaeological data from regions and periods with low numbers of 14C datings can be incorporated into models of past population dynamics.  相似文献   
905.
906.
Soft‐stone vessels are a prominent feature of ancient culture throughout south‐east Arabia and the Gulf. Chlorite and steatite occur naturally in the al‐Hajar Mountains of the United Arab Emirates (UAE) and Oman; but until now, apart from the discovery of a few unfinished pieces, ancient production of soft‐stone vessels had yet to be documented in Arabia. This paper reports the discovery and preliminary analysis of soft‐stone vessel production at the site of Aqir al‐Shamoos. At this small and secluded mountain village, a range of soft‐stone vessels that are well known in the south‐east Arabian Iron Age were produced on a scale far beyond what was needed for local consumption.  相似文献   
907.
For better or for worse, presidents receive much of the credit and much of the blame for their legislative success in Congress. Indeed, much has been written about the correlates of presidential success in Congress. In this article, we test the proposition that presidential success in Congress is mainly a function of context and the context of presidential interactions with Congress has changed over the past 50 years. Specifically, it is both the best of times and worst of times for presidential relations with the legislative branch. It is increasingly the case that because of partisan polarization in Washington, presidents can be quite successful, if they command a majority. However, if they face a divided government gridlock is the result and overcoming that gridlock has gotten to be more difficult over time.  相似文献   
908.
Today, as a result of fast-paced societal transformations, many small towns face severe developmental challenges and an uncertain future. Departing from the broader theory of developmental disequilibrium, we launch the concept of urban hibernation to explain the process of periodic small-town regress. The concept—along with its key stages and turning points—is presented to the background of urbanization processes encountered in Poland. At the same time, the focus on small towns offers an alternative and more context-sensitive explication to eclectic development models inherent to larger cities. As such, we argue that the concept of urban hibernation is apt to serve as a more precise research and planning tool in the context of small towns, and particularly in the critical moments of rise and recession. By applying a historical perspective, we address the importance of proper identification of the various and ever-changing city-forming factors, including their role for spatial planning at different scales. Urban hibernation should thus be considered as an intrinsic part of the geographic environment, which, due to the volatility of its socio-economic components, transcends the traditional rural–urban divide. Our conceptual contribution may thus serve as a background for a fuller understanding of the variability and dynamics of intra-urban structures.  相似文献   
909.
Our neoliberal governance model places a burden on planning to often take “responsibility” for the failure of market-lead governance to deliver its policy promises of betterment, security and future enjoyment. These include promised, but often-unachievable policies, such as those of increased global competitiveness for areas of structural economic decline; or housing affordability in areas of population growth and constrained land availability. Resultant policy failures then result in a scapegoating response where planning is held responsible. Examples include that economic development, or housing affordability, is obstructed by planning impediments, such as regulatory controls or process delays, which are claimed to hamper efficient market delivery. To deconstruct this neoliberal fantasy that planning often impedes policies for market-lead success, the article will first document exemplars of this scapegoating process. It will then explore the role of fantasy and ideology in governance policy formulation and, from a Lacanian perspective, the theorization that underlies this process. Then, it will investigate the role of the “scapegoat” for public policy facilitation so as to explain why planning is often placed in this role, and why this role is often ideologically necessary, at least for neoliberal governance, when planning undertaking its statutory responsibility of facilitating the public interest.  相似文献   
910.
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