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701.
结合工程实例,介绍了运用非开挖水平定向钻进技术实施原有管道更换的新技术,对旧有管道的更换探索一条经济可行的便捷之路,具有借鉴意义。 相似文献
702.
F. Dellisanti G. A. Pini F. Tateo F. Baudin 《International Journal of Earth Sciences》2008,97(3):601-616
The influence of tectonic strain on the diagenetic degree and illitization process of mixed-layers illite–smectite at shallow
crustal conditions was studied. For this purpose, the modal composition of clay fraction and illite FWHM parameters of argillites
deformed by a regional-scale fault zone were studied in detail by XRD, chemical analyses and by SEM observations. Analyses
were performed on deformed samples of the fault rock and compared with the non-deformed rocks off the fault zone. In addition,
this paper reports a detailed comparative analysis of deformed (shear surfaces and cleavage domains) and non-deformed domains
(lithon cores) of a scaly fabric in the fault rock. A systematic increase in illite concentration, a decrease of Kübler index
and FWHM(002) values, and an enrichment of K+ ions were observed in cleavage domains with respect to the non-deformed sediments off the fault zone and the lithon cores
within the fault rock. Migration of K+-rich fluids along scaly cleavage domains causes progressive conversion of smectite-rich I–S to illite-rich I–S and thickening
of illite crystallites along the c-direction. Changes in mineralogical and crystallographic parameters, therefore, seem to
be strongly controlled by shear plane development in highly sheared rocks. 相似文献
703.
The success in previous papers of this series in obtaining closed form solutions to the sedimentation of individual particles and to the suspensions of particles in fluids motivated the application of the same procedure to the turbulent flow of Newtonian fluids in conduits.The purpose of this paper is to present explicit equations for the Fanning friction factor and of the average velocity of a Newtonian fluid in a cylindrical tube, for any value of the Reynolds number and dimensionless roughness.Previously published equations for the friction coefficient are either implicit or explicit in the friction coefficient but dependent on the Reynolds number. Since the Reynolds number depends on the pipe diameter and fluid velocity, in both cases iterative method must be used to calculate the flowrate.By defining a dimensionless pipe diameter and a dimensionless average fluid velocity, and using conduit-flow material properties to define characteristic size and velocity parameters, explicit equations were obtained for the friction coefficient and for the average flow velocity valid for different roughness and flow regimes. 相似文献
704.
Comparative proteome analysis of butachlor-degrading bacteria 总被引:1,自引:0,他引:1
A Pseudomonas putida strain, named ER1, was isolated from an agricultural soil and found to actively degrade the herbicide butachlor. The enzyme
extracted from ER1 could degrade butachlor. Furthermore, incubation of ER1 in a medium containing 50 mg/kg of butachlor after
3 days resulted in the high butachlor-degrading enzyme activity of ER1. Response of ER1 to butachlor might be related to changes
in protein composition at both quantitative and qualitative levels. Total proteins were extracted from control strain (incubated
in the medium without butachlor) and the treated strain (incubated in the medium with butachlor). The proteins were separated
by two-dimensional gel electrophoresis. Of the total number of ER1 protein, 11 spots were significantly changed under butachlor
stress. Analysis by matrix-assisted laser desorption/ionization mass spectrometry and tandem mass spectrometry coupled with
database searching allowed the function of some proteins which were similar to the hydrolases activity or oxidoreductase activity. 相似文献
705.
The bowing potential of granitic rocks: rock fabrics, thermal properties and residual strain 总被引:1,自引:0,他引:1
The bowing of natural stone panels is especially known for marble slabs. The bowing of granite is mainly known from tombstones
in subtropical humid climate. Field inspections in combination with laboratory investigations with respect to the thermal
expansion and the bowing potential was performed on two different granitoids (Cezlak granodiorite and Flossenbürg granite)
which differ in the composition and rock fabrics. In addition, to describe and explain the effect of bowing of granitoid facade
panels, neutron time-of-flight diffraction was applied to determine residual macro- and microstrain. The measurements were
combined with investigations of the crystallographic preferred orientation of quartz and biotite. Both samples show a significant
bowing as a function of panel thickness and destination temperature. In comparison to marbles the effect of bowing is more
pronounced in granitoids at temperatures of 120°C. The bowing as well as the thermal expansion of the Cezlak sample is also
anisotropic with respect to the rock fabrics. A quantitative estimate was performed based on the observed textures. The effect
of the locked-in stresses may also have a control on the bowing together with the thermal stresses related to the different
volume expansion of the rock-forming minerals. 相似文献
706.
The northern Andes are a complex area where tectonics is dominated by the interaction between three major plates and accessory blocks, in particular, the Chocó-Panamá and Northern Andes Blocks. The studied Cauca Valley Basin is located at the front of the Chocó-Panamá Indenter, where the major Romeral Fault System, active since the Cretaceous, changes its kinematics from right-lateral in the south to left-lateral in the north. Structural studies were performed at various scales: DEM observations in the Central Cordillera between 4 and 5.7°N, aerial photograph analyses, and field work in the folded Oligo-Miocene rocks of the Serranía de Santa Barbara and in the flat-lying, Pleistocene Quindío-Risaralda volcaniclastic sediments interfingering with the lacustrine to fluviatile sediments of the Zarzal Formation.The data acquired allowed the detection of structures with a similar orientation at every scale and in all lithologies. These families of structures are arranged similarly to Riedel shears in a right-lateral shear zone and are superimposed on the Cretaceous Romeral suture.They appear in the Central Cordillera north of 4.5°N, and define a broad zone where 060-oriented right-lateral distributed shear strain affects the continental crust. The Romeral Fault System stays active and strain partitioning occurs among both systems. The southern limit of the distributed shear strain affecting the Central Cordillera corresponds to the E–W trending Garrapatas–Ibagué shear zone, constituted by several right-stepping, en-échelon, right-lateral, active faults and some lineaments. North of this shear zone, the Romeral Fault System strike changes from NNE to N.Paleostress calculations gave a WNW–ESE trending, maximum horizontal stress, and 69% of compressive tensors. The orientation of σ1 is consistent with the orientation of the right-lateral distributed shear strain and the compressive state characterizing the Romeral Fault System in the area: it bisects the synthetic and antithetic Riedels and is (sub)-perpendicular to the active Romeral Fault System.It is proposed that the continued movement of the Chocó–Panamá Indenter may be responsible for the 060-oriented right-lateral distributed shear strain, and may have closed the northern part of the Cauca Valley, thereby forming the Cauca Valley Basin.Conjugate extensional faults observed at surface in the flat-lying sediments of the Zarzal Formation and Quindío-Risaralda volcaniclastic Fan are associatedwith soft-sediment deformations. These faults are attributed to lateral spreading of the superficial layers during earthquakes and testify to the continuous tectonic activity from Pleistocene to Present.Finally, results presented here bring newinformation about the understanding of the seismic hazard in this area: whereas the Romeral Fault Systemwas so far thought to be themost likely source of earthquakes, themore recent cross-cutting fault systems described herein are another potential hazard to be considered. 相似文献
707.
利用青藏块体东北缘地区13、1年GPS观测资料,给出了本区地壳水平运动速度场及视应变场分布图,提出了由位移观测值直接求解块体旋转和变形参数的方法,初步研究了本区构造块体运动与变形特征.结果表明:①本区存在整体性向东-东南方的运动(速率约mm/a);②南部的甘肃-青海块体的运动较快,而北部的阿拉善块体的运动较慢,二者运动速率相差近6mm/a,祁连-海原断裂带左旋走滑运动显著.③自西向东存在北北东-北东东向压性运动;④阿拉善块体、甘肃-青海块体内部存在北西西向张性变形,阿拉善块体的整体张性变形更显著,鄂尔多斯块体西侧的块体交接地带为压性运动. 相似文献
708.
709.
710.
本文运用稳健估计法确定位移基准,以此为基础,识别影响均匀应变场的特殊位移信息,并在估计均匀应变参数的同时,也对特殊位移信息作出估计。用所提的分析方法对覆盖鲜水河断裂带的甘孜一塔公寺三角锁网三期成果进行了分析处理,研究了该断裂带的活动特征。 相似文献