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排序方式: 共有4355条查询结果,搜索用时 15 毫秒
921.
Gu Jie Kuang Cuiping
Engineer Nanjing Environmental Protection Research Institute Nanjing .
Senior Engineer Doctor Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1996,(3)
- A combined numerical model for computing mixing areas of pollution vertical jet discharging into tidal flows has been developed. This numerical model is composed of a 2-D depth-averaged dynamic far-field numerical model and a 2-D vertical dynamic near-field numerical model. The former uses finite node method to compute velocity, and improved finite node method to compute pollutant concentration distribution; the latter is a k-e turbulence model, and uses SIMPLE (Semi-Implicit Method for Pressure Linked Equations) method to compute velocity. At the same time, the former provides boundary conditions for the latter. This model can simulate both far- field pollutant concentration distribution and near-field vertical recirculation quickly and precisely. This model has been verified by measured data of pollutant F of the Dachang reach of the Changjing River and test data presented by Chen el al. (1992). On the basis of verification, the authors use a designed hydrograph to compute this mixing area for a cer 相似文献
922.
Tao Tongkang Yu Long Yan Jun Dong Zhiyong
Prof. Senior Engineer Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing
Graduate Student Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing Engineer Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing Associate Professor Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1997,(2)
This paper investigates the performance of geomembrane composites used as impervious andheat-insulating lining within a breakwater for a power station.The seepage field,distribution ofstress-strain contour and seepage discharge of hot water which has been treated as the inner thermalsource in the calculation of heat-insulation,have been given by three-dimensional calculation method coup-ling seepage with stress.The results indicate that the impervious and heat-insulation effect ofgeomembrane composites is significant. 相似文献
923.
Jin Weiliang Zhu Yuming Li Linpu Associate Professor Dr. -Eng. Zhejiang University Hangzhou
Engineer Metallurgical Building Design Research Institute Beijing
Associate Professor Dalian University of Technology Dalian 《中国海洋工程》1993,(4)
- Based on the Mohr-Coulomb failure principle and Rankine's theory, the laterally loaded pile ultimate resistance formulas of sand and soft clay proposed by Reese and Matlock respectively are discussed in this paper. The authors put forward the modified ultimate resistance formulas on the basis of which the ultimate resistance formula is developed for horizontally loaded pile in multi-layer soil in consideration of the effect of the overburden soil pressure on the calculation of soil layer. It is significant to the correct application of the ultimate resistance formulas in API and ZCS Rules into offshore engineering. 相似文献
924.
Yu Ke Su Weidong Postgraduate River Harbour Department Nanjing Hydraulic ResearchInstitute Nanjing Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1992,(1)
Generally, the reliability of ami -sliding and anti-overturning stability of an isolated gravity cylinder in a certain working period can be evaluated only when the statistical properties of short term stability are given first. The authors used numerical method to simulate the stability state function of a cylinder in short-crested sea, and further to get the probabilitical characteristics of the structure's stability by time domain analysis. The external loads appeared in the state functions include horizontal wave force, lift force and the respective moments, and the loads are correlated by co- spectrum. The numerical method presented in this paper can be used not only to solve short term reliability problem directly, but to calculate and analyse the long term reliability problem as well. For circular cylinders, an example of simulation and analysis is displayed in this paper. 相似文献
925.
试论我国海岸侵蚀信息系统的建立 总被引:6,自引:1,他引:6
本文通过对我国海岸侵蚀特点的分析,阐述了建立海岸侵蚀信息系统的必要性和基本方法,并给出了相应的结论。 相似文献
926.
Xue Hongchao Su Dehui Xu Fumin
Professor Research Institute of Coastal Ocean Engineering Hohai University Nanjing Doctor Dept. of Navigation Ocean Engineering Hohai University Nanjing Ph. D. Student Dept. of Navigation Ocean Engineering Hohai University Nanjing 《中国海洋工程》1995,(3)
- Combined with irregular wave-maker, the growing process of Wave Energy Spectrum in shallow water can be studied in wind wave channel on different water depth conditions, and its transformation characteristics and rules can be obtained. 相似文献
927.
Yao Guoquan Ma Zhixiong Ding Bingcan Prof. Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1993,(3)
This paper proposes ten types of improved floating breakwaters for experiment with regular waves, based on the experience in the development and manufacture of existing floating breakwaters both at home and abroad, and on the results of experimental studies on the hydraulic characteristics of several types of floating breakwaters. The wave heights before and behind the breakwaters are measured, the movements of floating breakwaters are observed and the chain forces of the floating breakwaters are measured. The paper studies and compares the hydraulic characteristics of the improved rectangular floating breakwaters of which the internal and external structures and their installation methods are changed. Finally the optimal type of structure is selected through experiments. 相似文献
928.
In this study, the combined actions of waves and tidal currents in estuarine and coastal areas are considered and a 2D mathematical model for sediment transport by waves and tidal currents has been established in orthogonal curvilinear coordinates. Non-equilibrium transport equations of suspended load and bed load are used in the model. The concept of background concentration is introduced, and the formula of sediment transport capacity of tidal currents for the Oujiang River estuary is obtained. The Dou Guoren formula is employed for the sediment transport capacity of waves. Sediment transport capacity in the form of mud and the intensity of back silting are calculated by use of Luo Zaosen' s formula. The calculated tidal stages are in good agreement with the field data, and the calculated velocities and flow directions of 46 vertical lines for 8 cross sections are also in good agreement with the measured data. On such a basis, simulations of back silting after excavation of the waterway with a sand bar under complicated boundary conditions in the navigation channel induced by suspended load, bed load and mud by waves and tidal currents are discussed. 相似文献
929.
930.
High-Order Models of Nonlinear and Dispersive Wave in Water of Varying Depth with Arbitrary Sloping Bottom 总被引:4,自引:0,他引:4
Hong Guangwen
Professor Coastal Ocean Engineering Research Institute Hohai University Nanjing P. R. China. 《中国海洋工程》1997,(3)
High-order models with a dissipative term for nonlinear and dispersive wave in water of va-rying depth with an arbitrary sloping bottom are presented in this article.First,the formal derivations toany high order of μ(=h/λ,depth to deep-water wave length ratio)and ε(=α/h,wave amplitude todepth ratio)for velocity potential,particle velocity vector,pressure and the Boussinesq-type equations forsurface elevation η and horizontal velocity vector U at any given level in water are given.Then,the exactexplicit expressions to the fourth order of μ are derived.Finally,the linear solutions of η,U,C(phase ce-lerity)and C_g(group velocity)for a constant water depth are obtained.Compared with the Airy theory,excellent results can be found even for a water depth as large as the wave legnth.The present high-ordermodels are applicable to nonlinear regular and irregular waves in water of any varying depth(from shal-low to deep)and bottom slope(from mild to steep). 相似文献