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971.
设计模式及其在J2ME中的应用 总被引:2,自引:0,他引:2
设计模式被描述为在一定的环境中解决某一类问题的方案.已成为现代软件系统设计的重要研究对象.介绍了J2ME体系结构,并深入探讨了3种典型设计模式在J2ME开发中的应用. 相似文献
972.
The most rapid and dramatic evolution in the solar corona occurs in events now known as Coronal Mass Ejections (CMEs). There have considerable importance for our understanding of the evolution of the mass and energy injected into the interplanetary medium. In this work, we have studied the relation of CMEs with geomagnetic activity for the period of 1988 to 1993. Not all CMEs are capable of producing geomagnetic disturbances. Our study indicates that the maximum chance of a geomagnetic disturbance occurs two to three days after a CME in association with B-type solar flares. 相似文献
973.
974.
The 2dF Galaxy Redshift Survey: the bJ -band galaxy luminosity function and survey selection function
Peder Norberg Shaun Cole Carlton M. Baugh Carlos S. Frenk Ivan Baldry Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Nicholas J. G. Cross Gavin Dalton Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole Jackson Ofer Lahav Ian Lewis Stuart Lumsden Steve Maddox Darren Madgwick John A. Peacock Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2002,336(3):907-931
975.
T. Le Berter N. Epchtein F. Guglielmo P. Le Sidaner 《Astrophysics and Space Science》1994,217(1-2):105-116
The goal of this article is to show that, if one avoids star forming regions, mass-losing AGB stars can generally be selected from the data that will be provided by the near-infrared surveys which are presently considered. Also, if IRAS data are available, the separation between carbon-rich and oxygen-rich stars can be operated by their positions in infrared colour diagrams. In extragalactic systems, red supergiants can be discriminated from AGB stars by their luminosities.based on observations obtained with the ESO 1-m telescope 相似文献
976.
977.
Kazuhiko Kano 《Bulletin of Volcanology》1996,58(2-3):131-143
A subaqueous volcaniclastic mass-flow deposit in the Miocene Josoji Formation, Shimane Peninsula, is 15–16 m thick, and comprises
mainly blocks and lapilli of rhyolite and andesite pumices and non- to poorly vesiculated rhyolite. It can be divided into
four layers in ascending order. Layer 1 is an inversely to normally graded and poorly sorted lithic breccia 0.3–6 m thick.
Layer 2 is an inversely to normally graded tuff breccia to lapilli tuff 6–11 m thick. This layer bifurcates laterally into
minor depositional units individually composed of a massive, lithic-rich lower part and a diffusely stratified, pumice-rich
upper part with inverse to normal grading of both lithic and pumice clasts. Layer 3 is 2.5–3 m thick, and consists of interbedded
fines-depleted pumice-rich and pumice-poor layers a few centimeters thick. Layer 4 is a well-stratified and well-sorted coarse
ash bed 1.5–2 m thick. The volcaniclastic deposit shows internal features of high-density turbidites and contains no evidence
for emplacement at a high temperature. The mass-flow deposit is extremely coarse-grained, dominated by traction structures,
and is interpreted as the product of a deep submarine, explosive eruption of vesicular magma or explosive collapse of lava.
Received: 10 January 1996 / Accepted: 23 February 1996 相似文献
978.
979.
Abstract The assemblage muscovite-quartz-staurolite-aluminium silicate-biotite-garnet-chlorite with H2O (SABGC assemblage) is invariant in the K2O-FeO-MgO-Al2O3-SiO2-H2O (KFMASH) system. Such five-phase AFM assemblages should be absent in nature, but reported occurrences from at least ten localities suggest that either the assemblage internally controls μH2O or non-KFMASH components stabilize one or more of the phases. Least-squares regression analysis of minerals from South Royalton and Gassetts, Vermont, USA, demonstrates that subsets of the minerals in single SABGC assemblages from both localities are related by balanced reactions involving water. These results are consistent with the interpretation that the subassemblages fixed μH2O at an arbitrary, specified pressure and temperature. Balanced dehydration reactions also may be written between minerals in the SABGC assemblages and four-phase assemblages from the same outcrops interpreted to have equilibrated at the same pressures and temperatures as the five-phase assemblages. These results suggest that different specimens from the same outcrops equilibrated at different values of μH2O, supporting the conclusion that μH2O was not controlled externally. We could not demonstrate internal control of fo2 using measured mineral compositions because oxygen balance occurred in all reactions derived by regression. Regression analysis of published mineral compositions from New Mexico failed to identify balanced reactions involving water or oxygen either among the phases in a single SABGC assemblage or between SABGC and nearby four-phase assemblages. These results demonstrate that neither μH2O nor fo2 were fixed by the SABGC assemblages at these localities, and permit the interpretations that the assemblages were stabilized by the non-KFMASH components Na or Ca and that μH2O and fo2 were controlled externally. 相似文献
980.
杨葆生 《广东海洋大学学报》1996,(2)
采用人工催产、波恩氏液固定、石蜡切片和H·E染色等方法,研究了杂交一代(F1)自交的受精细胞学过程。结果表明,鲫鲤杂交一代自交时有正常的受精细胞学过程。受精后,卵子完成第二次成熟分裂,排出第二极体;15min,雌雄性原核形成,20min,两性原核完全融合,形成二倍体的合子,40min,开始进行卵裂;1h,两个分裂球出现,本实验为F2代是二倍体提供了证据。 相似文献