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41.
钽铌湿法冶金中的环境污染与治理措施 总被引:1,自引:0,他引:1
薛梅 《稀有金属与硬质合金》2005,33(4):55-59
分析论述了钽铌冶金过程中的污染来源、污染形式、特点及危害,指出含氟化物、放射性、有机萃取剂的废渣、废水、废气是其主要污染物,并针对性地介绍了对这些污染物的治理措施。 相似文献
42.
In the southeast in Norrköping, Sweden, is a small fjord-like bay called Slätbaken. The water quality in Slätbaken—with its narrow outlet to the Baltic Sea—depends highly on the water quality of the streams that flow in it. While point pollution sources can be identified easily in general, the non-point sources are harder to find. The most important sources for non-point pollution are agricultural areas, and the pollutants are mostly nutrients like phosphorus, which come from the fertilisation of the fields. One important catchment area for Slätbaken is the 57.7 km2 Gisselö river basin (part of the topographic map 8GNO), which contains large agricultural areas.The transport of water pollutants is based on the same hydrological processes as erosion and sediment transport. The implementation of such a model in a GIS allows the analysis of a large area with a high resolution. When choosing the model, special attention was paid to the possibility of using a verified model that is easy to implement in a commercial GIS without the need of too much expert knowledge. This may allow its widespread use in many administrative applications that need non-point source information. A feasibility test for an enhanced GIS USLE model was done in the Gisselö drainage basin before it was implemented for all river basins in the whole administrative area of Norrköpings kommun.It is possible to use the suggested simplified USLE model to estimate the load of both pollutants and sediments, and it is able to show the areas that are critical for the water quality at the outlet of the water basin. The model has been evaluated in three studies [Int. J. Geogr. Inf. Syst. 2 (4) (1988) 365; A GIS to target critical areas for non point source management, in: Proceedings of the International Non Point Source Management Symposium, Austin, TX, November 7, 1989; Vatten 48 (1992) 117]. Then, implemented in a very simple GIS that allowed only rough estimates of terrain models and distances, the model was able to estimate the total suspended solids (TSS) and total phosphorus (TP) loads in the Svartå river basin of 1539 km2 in the same region as Gisselö and the Bornsjö river basin outside Stockholm. Besides an estimated R2 of 0.91–0.98 (verified by a more than one year measurement from manual and automated sampling stations in the whole river basin), the benefit with the GIS implemented USLE was the possibility to identify the risk areas with high spatial accuracy. During the last decade, both available databases and software have changed the possibilities to identify areas at risk of nutrient leakage. Schein [GIS Methods for Monitoring Sustainable Development by Analysis of Land-use and Land Cover Changes in the Surroundings of Linköping (Sweden), Institut für Photogrammetrie und Fernerkundung, Technische Universität Dresden, Germany] and Schein and Sivertun [Method and models for sustainable development monitoring and analyses in GIS, in: Proceedings of the International Workshop on Geo-Spatial Knowledge Processing for Natural Resource Management, University of Insubria, Varese, Italy, June 28–29, 2001] show that the enhanced land use data available through the European Union agricultural support program can be used together with remote sensing data to fine tune the modified GIS USLE model. The problems with the new 50×50 m digital elevation data now available are also pointed out here. Obvious errors in the data and possibilities to enhance the model by introducing a better terrain model were two important suggestions in these works. In this article, two modifications to the original model are suggested. One is enhancement of the digital terrain model by using height curves from the digital 1:50 000 scale topographic map, and the other is a smooth distance function that better reflects the impact of nutrients on water bodies.Because of its easy implementation on standard low cost systems, the GIS USLE model is suitable for analysing huge areas for critical places. The results can lead to more detailed studies in the risk areas thus identified or to investigations on the effect of land use changes, or can be used simply for taking care in the use of fertilisers and other chemicals in the critical agricultural areas. 相似文献
43.
针对广域污染源自动监控系统的特点和技术要求,必须采用中间分布式网络平台来满足系统的要求。通过对Microsoft的.NET、Sun的JavaONE以及OMG的CORBA这三种主要分布式网络平台的深入分析和比较研究,得出采用CORBA分布式平台是目前最佳方案的结论,并在“广东省广域水质污染源在线监测监控系统”课题中得到成功验证。 相似文献
44.
45.
汽车排气污染浓度预测 总被引:1,自引:0,他引:1
运用空气质量模式的基本理论,研究汽车尾气排放的扩散规律。选用多种典型空气质量模式,对汽车污染进行计算机模拟。在每一模式下,可对大气稳定度,混合层高度、扩散参数等进行选择计算;并能进行瞬时浓度及长期浓度的预测。设计的程序适用于各种气象务件、各种道路条件、各种车型。 相似文献
46.
The aim of this work is to provide a high performance air quality simulation using the sulphur transport Eulerian model 2 (STEM-II) program. First of all we optimize the sequential program with the aim of increasing data locality. Then, the optimized program is parallelized using OpenMP shared-memory directives. Experimental results on a 32-processor SGI Origin 2000 show that the parallel program achieves important reductions in the execution times. 相似文献
47.
液压介质的污染是液压元件过早磨损的主要原因。介绍了污染源产生的原因及污染颗粒的磨损机理,结合自己工作中的实例论述了液压介质清洁度对液压润滑系统的重要性。 相似文献
48.
49.
化学实验教学中的环保问题浅析 总被引:2,自引:0,他引:2
阐述了化学实验教学中存在的污染问题,分析了化学实验中污染的来源和污染特性,提出了消除或减轻化学实验性污染的必要性,并说明了实现化学实验绿色化的几种方法. 相似文献
50.