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991.
��Based on demonstration of the gas source,the thermal evoluation of organic matters and the conditions of forming gas reservoir etc.,the authors consider that the north part in Erduosi basin is the favourable region for expiorating the coal-formed gas.Source beds are mainly thy coal series in Carboniferous and Permian,reservoirs and cap rocks are mainly the Shihezi formation of Permian.There are many types of trap in this region,but the key point of exploration should be the anticlines.Four favourable areas are respectively evaluated in this paper also. 相似文献
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Hongdu Huang W. H. Donnellan III J. H. Jones 《Journal of the American Oil Chemists' Society》1990,67(6):406-414
Surfactants that may be suitable for application in enhanced oil recovery have been produced from C22 and C26 paraffinic and naphthenic petroleum fractions by a two-step process. The hydrocarbon feed stocks were first oxidized in the
vapor-phase, followed by neutralization of the oxidized products with aqueous alkali. As a result, dilute solutions of organic
acid salts were produced that achieved ultralow (<10−2 dyne/cm) interfacial tensions against a synthetic oil. Surfactant solutions that exhibited the lowest interfacial tensions
(IFTs) were prepared from neutralizations that used low concentrations of sodium hydroxide rather than sodium silicate, sodium
tripolyphosphate, or sodium carbonate. Neutralizations that used sodium silicate or sodium carbonate resulted in surfactant
solutions having IFT profiles that were less sensitive to the electrolyte concentration. When sodium hydroxide was combined
with either sodium silicate or sodium tripolyphosphate in the neutralizations, solutions having intermediate IFT properties
were produced. The amount of alkali used in the neutralizations was observed to affect the IFT properties of the resultant
surfactant solution. The electrolyte concentration at which the minimum IFT occurred was inversely related to the pH of the
surfactant solution. For surfactant solutions of common pH prepared from different concentrations of oxidized product, the
minimum IFTs all occurred at the same concentration of electrolyte. Surfactant solutions remained interfacially active even
in the presence of significant concentrations of calcium chloride. One pore volume of a solution containing only about 1%
of active surfactant recovered 42.0% of the residual oil in a tertiary core-flood experiment. 相似文献
996.
An experimental and theoretical study of reaction injection molding (RIM) of polyurea was conducted in this work. A lab-scale RIM machine was used to carry out the polyurea bulk polymerizations. A “free-table” viscometer was designed to measure the fast rheological changes and liquid-solid transition. A mathematical model was proposed to simulate the fast reaction and rheological changes in the polyurea RIM process. The parameters of this model were determined based on the solution polymerization data from FTIR and Haake rheometer measurements. Combined with an appropriate heat transfer equation, this model predicts fairly well the adiabatic temperature and viscosity rises of bulk polyurea reactions in RIM. 相似文献
997.
采用相干态正交化展开方法,对三量子比特的纠缠度影响因素进行了分析研究,并运用数值计算,结合解析解,在光场初态为真空态的相互作用过程中,对三量子比特的纠缠情况进行了研究.分析了三个全同的量子比特纠缠度随光场频率的变化规律以及光场量子比特耦合强度对三量子比特纠缠度的影响.研究结果表明,三量子比特的本征能量和共生纠缠度随光场... 相似文献
998.
999.
Daqiang Zhang Hongyu Huang Jingyu Zhou Feng Xia Zhe Chen 《Mobile Networks and Applications》2013,18(6):803-813
Vehicular Ad Hoc Networks (VANETs) can provide value-added services to both drivers and passengers with on-board vehicular communication systems. Node mobility and volatile wireless connection in VANETs affect inter-contact time (T I ) between mobile nodes, which greatly degrades the performance of vehicular applications. Nevertheless, the node spatial distribution in VANETs is another important factor especially in real applications. It positively affects the inter-contact time of vehicular nodes. By leveraging it, we can significantly improve the performance of data transmissions and inter-vehicle communication. To this end, we investigate the data collected from around 4,000 taxisin Shanghai and propose in this paper an efficient hot road mobility model. We find that most taxis distribute on some hot roads, which makes the node spatial distribution follow the power law. Based on this observation, we propose the concepts of indirect contact and heterogeneous inter-contact time (T H ) to reveal how hot roads can change the distribution of inter-contact time. We find that the tail distribution of T H also appears the power law, and both node spatial distribution and T H distribution decay at least as the power law. We further propose a model for detecting vehicle mobility in hot roads, which can generates synthetic traces that captures both spatial and temporal features of nodes in VANETs. 相似文献
1000.
Chien-Chung Shen Srisathapornphat C. Rui Liu Zhuochuan Huang Jaikaeo C. Lloyd E.L. 《Mobile Computing, IEEE Transactions on》2004,3(1):18-32
The topology of an ad hoc network has a significant impact on its performance in that a dense topology may induce high interference and low capacity, while a sparse topology is vulnerable to link failure and network partitioning. Topology control aims to maintain a topology that optimizes network performance while minimizing energy consumption. Existing topology control algorithms utilize either a purely centralized or a purely distributed approach. A centralized approach, although able to achieve strong connectivity (k-connectivity for k /spl ges/ 2), suffers from scalability problems. In contrast, a distributed approach, although scalable, lacks strong connectivity guarantees. We propose a hybrid topology control framework, cluster-based topology control (CLTC) that achieves both scalability and strong connectivity. By varying the algorithms utilized in each of the three phases of the framework, a variety of optimization objectives and topological properties can be achieved. In this paper, we present the CLTC framework; describe topology control algorithms based on CLTC and prove that k-connectivity is achieved using those algorithms; analyze the message complexity of an implementation of CLTC, namely, CLTC-A, and present simulation studies that evaluate the effectiveness of CLTC-A for a range of networks. 相似文献