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91.
The design of highly efficient, stable, and noble‐metal‐free bifunctional electrocatalysts for overall water splitting is critical but challenging. Herein, a facile and controllable synthesis strategy for nickel–cobalt bimetal phosphide nanotubes as highly efficient electrocatalysts for overall water splitting via low‐temperature phosphorization from a bimetallic metal‐organic framework (MOF‐74) precursor is reported. By optimizing the molar ratio of Co/Ni atoms in MOF‐74, a series of Cox Niy P catalysts are synthesized, and the obtained Co4Ni1P has a rare form of nanotubes that possess similar morphology to the MOF precursor and exhibit perfect dispersal of the active sites. The nanotubes show remarkable hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalytic performance in an alkaline electrolyte, affording a current density of 10 mA cm?2 at overpotentials of 129 mV for HER and 245 mV for OER, respectively. An electrolyzer with Co4Ni1P nanotubes as both the cathode and anode catalyst in alkaline solutions achieves a current density of 10 mA cm?2 at a voltage of 1.59 V, which is comparable to the integrated Pt/C and RuO2 counterparts and ranks among the best of the metal‐phosphide electrocatalysts reported to date.  相似文献   
92.
Understanding regional-scale water resource systems requires understanding coupled hydrologic and climate interactions. The traditional approach in the hydrologic sciences and engineering fields has been to either treat the atmosphere as a forcing condition on the hydrologic model, or to adopt a specific hydrologic model design in order to be interoperable with a climate model. We propose here a different approach that follows a service-oriented architecture and uses standard interfaces and tools: the Earth System Modeling Framework (ESMF) from the weather and climate community and the Open Modeling Interface (OpenMI) from the hydrologic community. A novel technical challenge of this work is that the climate model runs on a high performance computer and the hydrologic model runs on a personal computer. In order to complete a two-way coupling, issues with security and job scheduling had to be overcome. The resulting application demonstrates interoperability across disciplinary boundaries and has the potential to address emerging questions about climate impacts on local water resource systems. The approach also has the potential to be adapted for other climate impacts applications that involve different communities, multiple frameworks, and models running on different computing platforms. We present along with the results of our coupled modeling system a scaling analysis that indicates how the system will behave as geographic extents and model resolutions are changed to address regional-scale water resources management problems.  相似文献   
93.
The quest for ‘theory’ in the Building Research & Information special issue ‘Developing Theories of the Built Environment’ (36(3) 2008) needs to be understood within a larger historical and political context. It would benefit from engaging with a rich vein of work on the production of the built environment over the last 30 years. Theory inherently develops in the political context in which it exists; if it fails to do so, it may be dangerous. This commentary traces the intellectual underpinning concerned with understanding the process of change in the built environment, particularly the result of changes in social relations and the social labour process. The production of the built environment is seen as encompassing all the social processes concerned with producing the built environment, built products, buildings and infrastructure, and out of natural resources, whilst consumption is applied to all the processes involved in consuming these, including the well-being of tenants. And between these are situated the processes of exchange, distribution, and circulation, involving complex webs of relations between developers, builders, and landlords and landowners. The challenge is not only to engage and learn from past work, but also to state explicitly what is currently driving the need for a theory (or set of theories).

La quête de la « théorie » dans ce numéro spécial de Building Research & Information consacré aux théories du développement du milieu bâti (volume 36(3), 2008) doit être comprise dans un contexte historique et politique plus large. Elle aurait intérêt à s'appuyer sur les nombreux travaux concernant la production du cadre bâti publiés au cours de ces 30 dernières années. La théorie se développe, de manière inhérente, dans le contexte politique dans lequel elle existe; dans le cas contraire, la situation pourrait devenir dangereuse. Cet article analyse le raisonnement intellectuel sous-jacent concernant la compréhension du processus de changement dans le milieu bâti, notamment les conséquences des changements dans les relations sociales et dans le processus social du travail. La production du cadre bâti est considérée comme englobant tous les processus sociaux liés à la production du cadre bâti, des produits de construction, des bâtiments et des infrastructures et aux ressources naturelles alors que la consommation s'applique à tous les processus qui entrent en jeu dans la consommation de ceux-ci, y compris le bien-être des occupants. Entre ces deux notions, on trouve les processus d'échange, de distribution et de circulation qui font intervenir des réseaux de relations entre promoteurs, constructeurs, bailleurs et propriétaires fonciers. La difficulté ne vient pas seulement du fait qu'il faut tirer profit des travaux et de l'expérience passés mais qu'il faut également expliquer ce qui motive aujourd'hui la nécessité d'une théorie (ou d'un ensemble de théories).

Mots clés: cadre bâti, cadres conceptuels, consommation, processus de travail, cadre politique, production, relations sociales  相似文献   
94.
95.
Comments on three articles (see records 2005-11115-003, 2005-11115-004, and 2005-11115-005) on the status of children's mental health services in the United States, which appeared in the September 2005 issue of the American Psychologist. The current authors suggest that, although this series of articles provides important information, the articles fall short in meeting the mark of comprehensively describing the solutions necessary to effectively address the crisis facing children's mental health in this country. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
本文提出了高层半钢性连接钢框架二阶效应,包括P—△和P-δ效应的实用简化计算方法,该法便于手算。经验算本文的简化计算结果与精确的电算结果吻合甚好,其精度完全满足工程设计需要。本文对常见的五种高强螺栓梁柱连接的连接铡度进行了计算分析,给出了正常使用荷载下横梁线刚度和节点刚度比值的取值范围。本文还对半铡性连接以及P-△和P—δ效应对框架工作性能的影响进行了研究。  相似文献   
97.
介绍了大型岩石基底摩擦试验机的组成和顶框架的结构,分析了顶框架的侧框架、立柱和顶部网格梁的受力情况,提出了设计原理.  相似文献   
98.
企业领域的面向对象应用框架研究是现代面向对象应用框架技术的重要趋势之一.应用框架可以增强大型应用软件代码的重用性和可扩充性.针对目前化工过程系统软件中存在的问题,采用面向对象应用框架方法,建立起化工过程系统的通用模型.结合使用本模型完成的国家教委项目--化工仿真系统来阐述该模型.  相似文献   
99.
100.
The increasing computational needs of parallel applications inevitably require portability across parallel architectures, which now include heterogeneous processing resources, such as CPUs and GPUs, and multiple SIMD/SIMT widths. However, the lack of a common parallel programming paradigm that provides predictable, near-optimal performance on each resource leads to the use of low-level frameworks with architecture-specific optimizations, which in turn cause the code base to diverge and makes porting difficult. Our experiences with parallel applications and frameworks lead us to the conclusion that achieving performance portability requires a common set of high-level directives and efficient mapping onto each architecture.  相似文献   
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