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101.
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103.
应用地球化学方法评价断层的封闭性 总被引:8,自引:1,他引:7
断层的封闭性和连通性研究对于了解断层在油气成藏和石油开发中的影响具有重要的意义.根据断层附近油藏的地球化学特征, 可以研究排烃期断层的封闭性.在涠西南凹陷油田的研究工作中, 通过断层两端油层的化学组成指纹的差异, 证实了断层的存在, 虽然断距较小, 但仍影响了油藏的连通.对欧利坨子地区靠近断层的油藏分析表明, 本区的深大断裂可以作为油气的有效通道, 靠近断层油藏成熟度较高, 且含氮化合物较丰富.本研究提供的2个实例证实地球化学方法用于判断断层的封闭性有着不可替代的优越性. 相似文献
104.
J. Radebaugh R.D. Lorenz R.L. Kirk J.I. Lunine R.M.C. Lopes T.G. Farr B. Stiles H. Zebker L. Wye K.L. Mitchell R.D. West The Cassini Radar Team 《Icarus》2011,211(1):672-685
Titan’s enigmatic Xanadu province has been seen in some detail with instruments from the Cassini spacecraft. The region contains some of the most rugged, mountainous terrain on Titan, with relief over 2000 m. Xanadu contains evolved and integrated river channels, impact craters, and dry basins filled with smooth, radar-dark material, perhaps sediments from past lake beds. Arcuate and aligned mountain chains give evidence of compressional tectonism, yet the overall elevation of Xanadu is puzzlingly low compared to surrounding sand seas. Lineations associated with mountain fronts and valley floors give evidence of extension that probably contributed to this regional lowering. Several locations on Xanadu’s western and southern margins contain flow-like features that may be cryovolcanic in origin, perhaps ascended from lithospheric faults related to regional downdropping late in its history. Radiometry and scatterometry observations are consistent with a water-ice or water-ammonia-ice composition to its exposed, eroded, fractured bedrock; both microwave and visible to near-infrared (v-nIR) data indicate a thin overcoating of organics, likely derived from the atmosphere. We suggest Xanadu is one of the oldest terrains on Titan and that its origin and evolution have been controlled and shaped by compressional and then extensional tectonism in the icy crust and ongoing erosion by methane rainfall. 相似文献
105.
A mathematical solution for solute transport in a three-dimensional porous medium with a patch source under steady-state, uniform ground water flow conditions was developed by Domenico (1987). The solution derivation strategy used an approximate approach to solve the boundary value problem, resulting in a nonexact solution. Variations of the Domenico (1987) solution are incorporated into the software programs BIOSCREEN and BIOCHLOR, which are frequently used to evaluate subsurface contaminant transport problems. This article mathematically elucidates the error in the approximation and presents simulations that compare different versions of the Domenico (1987) solution to an exact analytical solution to demonstrate the potential error inherent in the approximate expressions. Results suggest that the accuracy of the approximate solutions is highly variable and dependent on the selection of input parameters. For solute transport in a medium-grained sand aquifer, the Domenico (1987) solution underpredicts solute concentrations along the centerline of the plume by as much as 80% depending on the case of interest. Increasing the dispersivity, time, or dimensionality of the system leads to increased error. Because more accurate exact analytical solutions exist, we suggest that the Domenico (1987) solution, and its predecessor and successor approximate solutions, need not be employed as the basis for screening tools at contaminated sites. 相似文献
106.
N. R. Parley N. McBride S. F. Green C. A. Haswell W. I. Clarkson D. J. Christian A. Collier-Cameron N. A. Evans A. Fitzsimmons C. Hellier S. T. Hodgkin K. Horne J. Irwin S. R. Kane F. P. Keenan T. A. Lister A. J. Norton J. P. Osborne D. Pollacco R. Ryans I. Skillen R. A. Street R. G. West P. J. Wheatley 《Earth, Moon, and Planets》2005,97(3-4):261-268
The SuperWASP project is an ultra-wide angle search for extra solar planetary transits. However, it can also serendipitously detect solar system objects, such as asteroids and comets. Each SuperWASP instrument consists of up to eight cameras, combined with high-quality peltier-cooled CCDs, which photometrically survey large numbers of stars in the magnitude range 7–15. Each camera covers a 7.8 × 7.8 degree field of view. Located on La Palma, the SuperWASP-I instrument has been observing the Northern Hemisphere with five cameras since its inauguration in April 2004.The ultra-wide angle field of view gives SuperWASP the possibility of discovering new fast moving (near to Earth) asteroids that could have been missed by other instruments. However, it provides an excellent opportunity to produce a magnitude-limited lightcurve survey of known main belt asteroids. As slow moving asteroids stay within a single SuperWASP field for several weeks, and may be seen in many fields, a survey of all objects brighter than magnitude 15 is possible. This will provide a significant increase in the total number of lightcurves available for statistical studies without the inherent bias against longer periods present in the current data sets.We present the methodology used in the automated collection of asteroid data from SuperWASP and some of the first examples of lightcurves from numbered asteroids. 相似文献
107.
W. I. Clarkson B. Enoch C. A. Haswell A. J. Norton D. J. Christian A. Collier Cameron S. R. Kane K. D. Horne T. A. Lister R. A. Street R. G. West D. M. Wilson N. Evans A. Fitzsimmons C. Hellier S. T. Hodgkin J. Irwin F. P. Keenan J. P. Osborne N. R. Parley D. L. Pollacco R. Ryans I. Skillen P. J. Wheatley 《Monthly notices of the Royal Astronomical Society》2007,381(2):851-864
108.
A. M. S. Smith A. Collier Cameron D. J. Christian W. I. Clarkson B. Enoch A. Evans C. A. Haswell C. Hellier K. Horne J. Irwin S. R. Kane T. A. Lister A. J. Norton N. Parley D. L. Pollacco R. Ryans I. Skillen R. A. Street A. H. M. J. Triaud R. G. West P. J. Wheatley D. M. Wilson 《Monthly notices of the Royal Astronomical Society》2006,373(3):1151-1158
The evolution of the Alfvén turbulence due to three-wave interactions is discussed using kinetic theory for a collisionless, thermal plasma. There are three low-frequency modes, analogous to the three modes of compressible magnetohydrodynamics (MHD). When only Alfvén waves are considered, the known anisotropy of turbulence in incompressible MHD theory is reproduced. Inclusion of a fast mode wave leads to the separation of turbulence into two regimes: small wave numbers where three-wave processes involving a fast mode are dominant, and large wave numbers where the three Alfvén wave process is dominant. Possible application of the anisotropic Alfvén turbulence to the interstellar medium and dissipation of magnetic energy in magnetars are discussed. 相似文献
109.
Earth, Moon, and Planets - 相似文献
110.
Pollutant emissions such as aerosols and tropospheric ozone precursors substantially influence climate. While future century-scale
scenarios for these emissions have become more realistic through the inclusion of emission controls, they still potentially
lack consistency between surface pollutant concentrations and regional levels of affluence. We find that the default method
of scenario construction, whereby emissions factors converge to similar values in different regions, does not yield pollution
concentrations consistent with historical experience. We demonstrate a methodology combining use of an integrated assessment
model and a three-dimensional atmospheric chemical transport model, whereby a reference scenario is constructed by requiring
consistent surface pollutant concentrations as a function of regional income over the 21st century. By adjusting air pollutant
emission control parameters, we improve consistency between projected PM2.5 and economic income among world regions through time; consistency for ozone is also improved but is more difficult to achieve
because of the strong influence of upwind world regions. Reference case pollutant emissions described here were used to construct
the RCP4.5 Representative Concentration Pathway climate policy scenario. 相似文献