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101.
基于WebGIS的粗泥沙集中来源区电子地图系统建设,以粗泥沙集中来源区作为研究区域,以黄河中游粗泥沙集中来源区水土保持工作流程(包括规划设计、计划管理、综合治理、预防监督和淤地坝管理等)为主线,依托黄河流域水土保持生态与环境监测系统网络、黄河流域水土保持监测系统数据库,建立覆盖黄河流域、黄土高原区、多沙粗沙区、粗泥沙集中来源区,面向不同水土保持管理层的水土保持监测与管理信息系统。  相似文献   
102.
山西省水资源开发利用对策措施   总被引:2,自引:0,他引:2  
通过对山西省水资源状况及面临的水资源形势分析,提出了山西省水资源开发和利用的对策。山西省在未来10年内水资源开发利用应继续遵循“西引黄河,东抓蓄调,腹部盆地节调并举”的战略思想,只有加强以农田水利为重点的农村基础设施建设,继续抓好大中型水利工程的立项建设,鼓励支持社会各方力量兴办中小型水利工程,加强农业节水工程建设,推广农业高效用水技术,才能使山西省大部分地区的水资源短缺状况将得到极大改善,为全省国民经济和社会可持续发展提供支撑和保障。  相似文献   
103.
A system for the direct measurement of steam flow in steam lines after a steam generator, which utilizes a special design of pneumometric tubes and a computing unit that accounts for variation in steam pressure, has been developed to improve the quality of water-level regulation in the steam generators of VVéR-1000 power-generating units in the stationary and transitional modes. The advantage of the pneumometric tubes consists in their structural simplicity, high erosion resistance, and absence of irrevocable losses during measurement of steam flow. A similar measurement system is used at foreign NPP. The measurement system in question has been placed in experimental service at the No. 3 unit of the Balakovo NPP, and has demonstrated its worthiness. This measurement system can also be used to determine steam flow in the steam lines of NPP units with VVéR-1000 and VVéR-440 reactors, and PBMK-1000 power-generating units. __________ Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 23–26.  相似文献   
104.
The use of computer models offers a general and flexible framework that can help to deal with some of the complexities and difficulties associated with the development of water management plans as prescribed by the Water Framework Directive. However, despite the advantages modelling presents, the integration of information derived from models into policy is far away from being trivial or the norm. Part of the difficulties of this integration is rooted in the lack of confidence policy makers have on the incorporation of modelling information into policy formulation. In this paper we examine the reasons for this apparent lack of confidence and explore how some tools, presently in use, address this problem. We conclude that public confidence in models is highly dependent on the way uncertainties are addressed and suggest possible directions of action to improve the current situation. Four real case studies illustrate how computer models have been used in The Netherlands for carrying out management plans at regional and national scale. We suggest that the solution to integrate modelling information into policy formulation lies on both the modelling and the policy-making communities.  相似文献   
105.
梁卫东  徐敏 《吉林水利》2007,(10):26-28
中部地区水资源总量为39.61亿m3。城市用水与农业、生态用水矛盾突出,城市供水能力不足,水污染问题严重,地下水超采严重,水资源开发利用不协调。该区水资源已无进一步开发利用的潜力,需通过调水工程解决缺水问题。水资源配置思路为从地处松花江上游的丰满水库引水,增加供水能力。  相似文献   
106.
全球气候变暖对水资源的影响   总被引:6,自引:0,他引:6  
全球气候变暖加剧了干旱、洪涝、台风等自然灾害的发生,是目前各国政府和社会公众普遍关注的热点问题。根据有关资料对气候变暖研究进展情况作相关介绍,可供参考。  相似文献   
107.
Suitability of sweet sorghum in Greece, where irrigation supply during crop development is limited as rainfall is scarce and evapotranspiration loss is high, is examined in relation with radiation availability. A two-year field experiment was conducted, in central Greece, imposing four soil water regimes via different irrigation treatments: (1) Highly irrigated, (2) Highly irrigated till anthesis when irrigation stopped, (3) Medium irrigated, and (4) Low irrigated. It was found that above-ground dry biomass production from non-water-stressed sweet sorghum plants suggests a high productivity potential among C4 crops. Under water shortage, radiation use efficiency may be significantly lower. Radiation use efficiency seems to be linearly related to water consumption. Stressed plants (probably except severely stressed) seem to use available water more efficiently than unstressed plants. The slope of the line relating dry matter produced and water evapotranspired increases the sooner the stress is sensed. Yield reduction resulting from post-anthesis irrigation stopage is very little. High water use efficiency values tend to be related with low radiation use efficiency values.  相似文献   
108.
Optimal Locations of Groundwater Extractions in Coastal Aquifers   总被引:1,自引:0,他引:1  
A regional water supply management model for coastal aquifers was developed. One of its outcomes is the definition of the optimized locations for groundwater withdrawal. Such a tool permits the analysis of alternative plans for groundwater extraction and the sustainable use of water resources in a coastal aquifer subject to saltwater intrusion. The principal components are the evolutionary optimization and the analytical/numerical simulation models. The optimization technique looks for the best well locations taking into consideration the economic results and the satisfaction of the societal water demand. However these two concerns are conditioned by trying to control the saltwater intrusion, i.e., preserving the environmental equilibrium. The simulation model uses the governing mathematical equations for groundwater movement to find the interface between freshwater and saltwater. Because of the non-linearity in the system and the possibility of a jumping interface, a security distance was defined. This is a controlling variable which can be set by the decision makers. The model was applied to a typical case with interesting results. For example, diagrams showing the relationship between the location of the wells and the security distance(s) are of importance to the managers. It was also crucial to have an understanding of the tradeoffs between groundwater withdrawals, positions of the wells from the coast line, and the security distance. The model was also applied to a real case in order to relate the extractions, distances and artificial recharge (not presented in this paper).  相似文献   
109.
王威 《水利电力机械》2007,29(11):1-5,7
黄埔发电厂#6发电机转冷水铜离子含量超标,通过对缺陷原因进行分析,针对二级水封的特性对溢出的转冷水进行回收并利用化学凝结水处理去除溶出的铜离子,通过控制转冷水的pH值最终减缓铜管的腐蚀.  相似文献   
110.
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