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101.
基于交互多模型的水下目标跟踪方法   总被引:1,自引:0,他引:1  
According to the requirements of real-time performance and reliability in underwater maneuvering target tracking as well as clarifying motion features of the underwater target, an interacting multiple model algorithm based on fuzzy logic inference (FIMM) is proposed. Maneuvering patterns of the target are represented by model sets, including the constant velocity model (CA), the Singer mode~, and the nearly constant speed horizontal-turn model (HT) in FIMM technology. The simulation results show that compared to conventional IMM, the reliability and real-time performance of underwater target tracking can be improved by FIMM algorithm.  相似文献   
102.
The electromagnetic mass damper (EMD) control system, as an innovative active control system to reduce structural vibration, offers many advantages over traditional active mass driver/damper (AMD) control systems. In this paper, studies of several EMD control strategies and bench-scale shaking table tests of a two-story model structure are described. First, two structural models corresponding to uncontrolled and Zeroed cases are developed, and parameters of these models are validated through sinusoidal sweep tests to provide a basis for establishing an accurate mathematical model for further studies. Then, a simplified control strategy for the EMD system based on the pole assignment control algorithm is proposed. Moreover, ideal pole locations are derived and validated through a series of shaking table tests. Finally, three benchmark earthquake ground motions and sinusoidal sweep waves are imposed onto the structure to investigate the effectiveness and feasibility of using this type of innovative active control system for structural vibration control. In addition, the robustness of the EMD system is examined. The test results show that the EMD system is an effective and robust system for the control of structural vibrations.  相似文献   
103.
Building damage in Dujiangyan during Wenchuan Earthquake   总被引:2,自引:1,他引:1  
A field damage survey of 1,005 buildings damaged by the Wenchuan Earthquake in Dujiangyan City was carried out and the resulting data was analyzed using the statistical method. It is shown that buildings that were seismically designed achieved the desired seismic fortification target; they sustained less damage than the non-seismically designed buildings. Among the seismically designed buildings investigated, RC frame buildings performed the best in terms of seismic resistance. Masonry buildings with a ground story of RC frame structure were the second best, and masonry buildings performed the worst. Considering building height, multistory buildings sustained more severe damage than high-rise buildings and 2- and 3-story buildings. Compared to residential buildings, public buildings, such as schools and hospitals, suffered more severe damage.  相似文献   
104.
An investigation of soil-pile-structure interaction is carried out, based on a large reciprocating compressor installed on an elevated concrete foundation (table top structure). A practical method is described for the dynamic analysis, and compared with a 3D finite element (FE) model. Two commercial software packages are used for dynamic analysis considering the soilpile-structure interaction (SPSI). Stiffness and damping of the pile foundation are generated from a computer program, and then input into the FE model. To examine the SPSI thoroughly, three cases for the soil, piles and superstructure are considered and compared. In the first case, the interaction is fully taken into account, that is, both the superstructure and soil-pile system are flexible. In the second case, the superstructure is flexible but fixed to a rigid base, with no deformation in the base (no SSI). In the third case, the dynamic soil-pile interaction is taken into account, but the table top structure is assumed to be rigid. From the comparison beteen the results of these three cases some conclusions are made, which could be helpful for engineering practice.  相似文献   
105.
An estimation of internal soliton forces on a pile in the ocean   总被引:2,自引:0,他引:2  
Internal soliton forces on oil-platform piles in the ocean are estimated with the Morison Formula. Different from sur- face wave forces, which change only in magnitude along a pile, internal soliton forces can be distributed over the entire pile in the water and they change not only in magnitude but also in direction with depth. Our calculations show that the maximum total force caused by a soliton with its associated current of 2.1 m s-1 is nearly equal to the maximum total force exerted by a surface wave with a wavelength of 300 m and a wave-height of 18 m. The total internal soliton force is large enough to affect the operations of marine oil platforms and other facilities. Therefore, the influence of internal solitons should not be neglected in the design of oil platforms.  相似文献   
106.
A careful selection of waste dumpsites, particularly hazardous ones, is very important for sustainable water resources management. Several laboratory experiments were carried out on the field samples to study adsorption capacity using p-dichlorobenzene (a solvent used in various industrial processes) as the test contaminant. The effect of parameters such as organic matter, clay, and iron and aluminium oxides, which are known to influence the soil adsorption capacity, are studied in the present work. Several soil samples from the Patancheru Industrial Area (Hyderabad, India) were collected and characterized. Only three soils, which had a comparatively high percentage of organic matter, clay, iron and aluminium oxide contents were used for the adsorption studies. The results clearly indicated a decrease in the adsorption capacity of the soils by as much as 75% when organic matter was removed. The other parameters such as clay and iron and aluminium oxides also play an important role in adsorption (57 and 39.8% reduction respectively). It was observed that out of the selected factors organic matter in the soils has the maximum effect regarding the adsorption of p-dichlorobenzene. Since the selected soils contain comparatively more organic matter, clay and iron and aluminium oxides in the selected industrial area, these can be used as sites for dumping hazardous waste, which can be further treated by methods like bioremediation.  相似文献   
107.
The upflow anaerobic sludge blanket process followed by the biological aerated filter process was employed to improve the removal of color and recalcitrant compounds from real dyeing wastewater. The highest removal efficiency for color was observed in the anaerobic process, at 8-h hydraulic retention time, seeded with the sludge granule. In the subsequent aerobic process packed with the microbe-immobilized polyethylene glycol media, the removal efficiency for chemical oxygen demand increased significantly to 75 %, regardless of the empty bed contact time. The average influent non-biodegradable soluble chemical oxygen demand was 517 mg/L, and the average concentration in effluent from the anaerobic reactor was 363 mg/L, suggesting the removal of some recalcitrant matters together with the degradable ones. The average non-biodegradable soluble chemical oxygen demand in effluent from the aerobic reactor was 87, 93, and 118 mg/L, with the removal efficiency of 76, 74, and 67 %, at 24-, 12-, and 8-h empty bed contact time, respectively. The combined anaerobic sludge blanket and aerobic cell-entrapped process was effective to remove the refractory compounds from real dyeing wastewater as well as in reducing organic loading to meet the effluent discharge limits. This integrated process is considered an effective and economical treatment technology for dyeing wastewater.  相似文献   
108.
北天山晚古生代蛇绿岩带的巴音沟蛇绿岩是该带的重要组成部分和典型代表。传统意义的巴音沟蛇绿岩带在区内分南北两支,南支为贝勒克蛇绿岩带,北支为巴音沟蛇绿岩带,分别代表早泥盆世末和早石炭世末的两条不同古洋壳残片。  相似文献   
109.
The aim of this research project is to identify, characterize and quantify natural attenuation (NA) processes in groundwater affected by emissions of abandoned waste disposal sites in Berlin-Kladow/Gatow, Germany. It is part of the funding priority called KORA established by the Federal Ministry for Education and Research (BMBF) to explore the extent to which NA can be used for remedial purposes for varied forms of soil and groundwater contamination. Information on the emission behaviour of individual parameters is generated on the basis of hydrogeochemical comparison of 20 years old and new data. Using groundwater-modelling and CFC-analysis, information on the transport and retention of pollutants in groundwater is compiled. The microbial colonization of contaminated aquifers is characterized by molecular biological methods [polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE)] to differentiate between contaminated and not contaminated zones.  相似文献   
110.
Here we report iron (Fe) isotopic data of three pure Fe solution standards (IRMM-014, GSB Fe, and NIST 3126a) and five widely used geological reference materials (RMs) from the United States Geological Survey and Geological Survey of Japan obtained on a Neptune Plus multi-collector–inductively coupled plasma–mass spectrometer (MC-ICP-MS) in our laboratory over the past 3 years. The instrumental mass bias was corrected by three independent methods: sample-standard bracketing (SSB), Ni doping?+?SSB, and 57Fe–58Fe double spike?+?SSB. Measurements reveal that both the Ni doping and double spike methods helped calibrate short-term fluctuations in mass bias. Collectively, almost all measurements of RMs yielded δ56Fe within?±?0.05 of recommended values, provided that each sample was measured four times on MC-ICP-MS. For the first time, new recommended values for NIST SRM3126a are reported (δ56Fe?=?0.363?±?0.006, 2SE, 95% CI; and δ57Fe?=?0.534?±?0.010, 2SE).  相似文献   
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