全文获取类型
收费全文 | 273篇 |
免费 | 9篇 |
国内免费 | 6篇 |
专业分类
测绘学 | 1篇 |
大气科学 | 5篇 |
地球物理 | 70篇 |
地质学 | 79篇 |
海洋学 | 58篇 |
天文学 | 46篇 |
综合类 | 2篇 |
自然地理 | 27篇 |
出版年
2024年 | 1篇 |
2021年 | 4篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 12篇 |
2014年 | 10篇 |
2013年 | 19篇 |
2012年 | 12篇 |
2011年 | 21篇 |
2010年 | 16篇 |
2009年 | 14篇 |
2008年 | 18篇 |
2007年 | 13篇 |
2006年 | 10篇 |
2005年 | 13篇 |
2004年 | 14篇 |
2003年 | 9篇 |
2002年 | 2篇 |
2001年 | 5篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有288条查询结果,搜索用时 15 毫秒
61.
Satoshi Sakai 《Progress in Oceanography》1986,17(3-4)
Laboratory experiments with a rotating tank confirm the bifurcation character of a barotropic flow driven by an inflow and an outflow described by Sakai (1986). The model, a circular basin with a topographic β-effect, simulates a mid-latitude oceanic feature. At a low Rossby number, stationary Rossby waves are observed which are symmetrical with a line connecting the inlet and the outlet. As the Rossby number increases, a bifurcation occurs and two kinds of vortex flows are observed. In the vortex, potential vorticity is almost uniform. In addition to the two vortex flows, a jet-like inertial flow can also be observed. In general, thre results of these experiments agree well with those of a low-order model and a numerical model. 相似文献
62.
Takashi Ishimaru Hirotaka Otobe Toshiro Saino Hiroshi Hasumoto Toshisuke Nakai 《Journal of Oceanography》1984,40(3):207-212
A realtime monitoring system for observing physical, biological, and optical oceanographic parameters in shallow waters was developed. It consists of a CTD with oxygen sensor, anin situ fluorometer, anin situ transmissometer, and anin situ quanta meter together with an on-deck quanta meter. The system is also equipped with a water sampling device. Water sampling can be done during the upward cast on the basis of depth profiles of temperature, salinity, oxygen,in situ fluorescence, transmittance, and underwater irradiance taken during the downward cast. 相似文献
63.
64.
65.
66.
67.
Satoshi Kanisawa 《Contributions to Mineralogy and Petrology》1969,20(2):164-176
The mineralogy and petrochemistry of the garnet-amphibolites from the highgrade part of the Abukuma metamorphic belt have been studied, using five analyses of rocks, five of hornblendes, three of garnets and one analysis of cummingtonite, Garnetiferous amphibolites are rich in Fe, whereas non-garnetiferous ones are rich in Mg, especially in cummingtonite-amphibolite. The chemical composition of hornblendes associated with garnet is pargasitic and rich in FeO and poor in CaO, but that of non-garnetiferous rocks is rich in MgO. The garnets are rich in almandine molecule. Mg/Mg + Fe2+ ratios of both hornblendes and garnets correspond with those of the host rocks. The development of garnet in the Adirondack metabasites belonging to the upper almandine-amphibolite and granulite facies is observed in Mg-rich rocks as well as in Fe-rich rocks, in which both garnet and hornblende are rich in Mg respectively. However, under the conditions of the andalusite-sillimanite type metamorphism as shown in the Abukuma Plateau, Fe-rich garnet occurs in Fe-rich basic rocks, but cummingtonite occurs in Mg-rich ones instead of Mg-rich garnet. Finally, the problem of polymetamorphism is discussed. The cummingtonite-amphibolite may be the product of polymetamorphism, and Mg-rich garnet which had been present previously was decomposed to cummingtonite and plagioclase by the subsequent regional metamorphism of andalusite-sillimanite type. 相似文献
68.
Jianghui Ji Hiroshi Kinoshita Lin Liu Guangyu Li Hiroshi Nakai 《Celestial Mechanics and Dynamical Astronomy》2003,87(1-2):113-120
We perform numerical simulations to explore the dynamical evolution of the HD 82943 planetary system. By simulating diverse planetary configurations, we find two mechanisms of stabilizing the system: the 2:1 mean motion resonance (MMR) between the two planets can act as the first mechanism for all stable orbits. The second mechanism is a dynamical antialignment of the apsidal lines of the orbiting planets, which implies that the difference of the periastron longitudes 3 librates about 180° in the simulations. We also use a semi-analytical model to explain the numerical results for the system under study. 相似文献
69.
Overview of the MITI Nankai Trough Wells: A Milestone in the Evaluation of Methane Hydrate Resources 总被引:4,自引:0,他引:4
Yoshihiro Tsuji Hisashi Ishida Masaru Nakamizu Ryo Matsumoto Satoshi Shimizu 《Resource Geology》2004,54(1):3-10
Abstract. Bottom-simulating reflectors suggestive of the presence of methane hydrates are widely distributed below the ocean floor around Japan. In late 1999, drilling of the MITI Nankai Trough wells was conducted to explore this potential methane hydrate resource and a Tertiary conventional structure. The wells are located in the Northwest Pacific Ocean off Central Japan at a water depth of 945 m. A total of six wells were drilled, including the main well, two pilot wells, and three post survey wells at intervals of 10–100 m. All wells except the first confirmed the occurrence of hydrates based on logging-while-drilling, wire-line logging and/or coring using a pressure and temperature coring system in addition to conventional methods. Based on the various well profiles, four methane hydrate-bearing sand-rich intervals in turbidite fan deposits were recognized. Methane hydrates fill the pore spaces in these deposits, reaching saturation of up to 80 % in some layers. The methane hydrate-bearing turbiditic sand layers are less than 1 m thick, with a total thickness of 12–14 m. The bottom depth of high hydrate concentration correlates well with the depth of the bottom-simulating reflector. Based on these exploration results, the Japanese government inaugurated a 16-year methane hydrate exploitation program in 2001. 相似文献
70.
Nanoscale occurrence of Pb in an Archean zircon 总被引:2,自引:0,他引:2
Satoshi Utsunomiya John W. Valley Simon A. Wilde 《Geochimica et cosmochimica acta》2004,68(22):4679-4686
We report, for the first time, a direct, atomic-scale characterization of Pb in zircon (4.4-3.1 Ga) from the early Archean Yilgarn craton in Australia using high-resolution HAADF-STEM. Two forms of Pb have been identified: Pb concentrated at ∼3 atom% as a nanoscale patch in zircon structure, and Pb concentrated within the amorphous domain created by fission fragment damage. The first result suggests that the Pb atoms directly substitute for Zr4+ in the zircon structure, and the latter observation demonstrates that Pb diffusion can occur through amorphous regions created by radiation damage, although volume diffusion is typically considered to be the dominant mechanism for Pb diffusion. Beyond the first percolation point, i.e., when the amorphous domains overlap and form a fully interconnected network of amorphous domains, there is a new pathway for the diffusion of Pb that is faster than volume diffusion through crystalline zircon. 相似文献