全文获取类型
收费全文 | 16672篇 |
免费 | 1940篇 |
国内免费 | 2936篇 |
专业分类
测绘学 | 904篇 |
大气科学 | 2472篇 |
地球物理 | 3333篇 |
地质学 | 8121篇 |
海洋学 | 2283篇 |
天文学 | 1863篇 |
综合类 | 1007篇 |
自然地理 | 1565篇 |
出版年
2024年 | 78篇 |
2023年 | 222篇 |
2022年 | 688篇 |
2021年 | 899篇 |
2020年 | 812篇 |
2019年 | 865篇 |
2018年 | 1084篇 |
2017年 | 1015篇 |
2016年 | 1003篇 |
2015年 | 751篇 |
2014年 | 954篇 |
2013年 | 1034篇 |
2012年 | 1005篇 |
2011年 | 1097篇 |
2010年 | 990篇 |
2009年 | 938篇 |
2008年 | 889篇 |
2007年 | 920篇 |
2006年 | 829篇 |
2005年 | 435篇 |
2004年 | 372篇 |
2003年 | 427篇 |
2002年 | 491篇 |
2001年 | 453篇 |
2000年 | 340篇 |
1999年 | 364篇 |
1998年 | 283篇 |
1997年 | 307篇 |
1996年 | 255篇 |
1995年 | 255篇 |
1994年 | 230篇 |
1993年 | 180篇 |
1992年 | 163篇 |
1991年 | 109篇 |
1990年 | 92篇 |
1989年 | 109篇 |
1988年 | 79篇 |
1987年 | 63篇 |
1986年 | 57篇 |
1985年 | 43篇 |
1984年 | 42篇 |
1983年 | 41篇 |
1982年 | 40篇 |
1981年 | 24篇 |
1980年 | 23篇 |
1979年 | 28篇 |
1978年 | 17篇 |
1977年 | 17篇 |
1975年 | 22篇 |
1973年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
501.
P. Yu. Petrov 《Lithology and Mineral Resources》2016,51(4):290-309
Structures and textures of the peloidal wackestones, as well as size, shape, and composition of peloidal grains, from the Mesoproterozoic (Middle Riphean) Sukhaya Tunguska carbonate platform in the Turukhansk Uplift (Siberia) are considered. It is shown that these grains formed in the course of diagenesis were closely associated with the microsparitic replacement and the formation of molar tooth (MT) structures. Diagenetic transformations of rocks were related to the activity of anaerobic microbial communities inside the buried carbonate silt layers. The microbial activity during diagenesis was governed by the carbonate sediment composition and conservation mechanism of the high-molecular organic matter of primary producers therein, since this organic matter was the nutritious substrate for the primary anaerobe communities. 相似文献
502.
B. F. Myasoedov S. N. Kalmykov Yu. M. Kulyako S. E. Vinokurov 《Geochemistry International》2016,54(13):1156-1167
In this paper, we consider the present-day situation and outlooks of the development of nuclear power generation in Russia and other countries. It was noted that the implementation of the concept of a closed nuclear-fuel cycle accepted in Russia relies on the solution of the problem of the disposal of spent nuclear fuel (SNF) and radioactive waste (RAW). This paper presents the main results of investigations focused on the development of radiation-safe methods of manufacturing nuclear fuel elements, including mixed uranium–plutonium oxide fuel for fast-neutron reactors; creation of low waste-production technologies of SNF processing and RAW disposal; and the analysis of fundamental features of the behavior and speciation of radionuclides in environmental objects for the development of efficient methods of radioecological monitoring and remediation of radionuclide-contaminated areas. 相似文献
503.
M. A. Solovyeva A. V. Starovoytov G. G. Akhmanov O. M. Khlystov A. V. Khabuev M. Yu. Tokarev D. A. Chensky 《Moscow University Geology Bulletin》2016,71(6):416-428
As a result of careful interpretation of the data of recent seismo-acoustic surveys, two major seismic complexes were identified in the structure of the upper sedimentary section of the north-western slope of Kukuy Griva (ridge). They are composed of several inner seismo-facies, which are very characteristic and separated with well-expressed regional reflector. Seismic and acoustic data revealed evidences of numerous landslide processes which were different in age and peculiarities of manifestation. For the first time, detailed schemes of seismo-facies distribution are compiled for major seismic complexes at the area. The boundary between seismic complexes is dated as 150 thousands years. It is shown that sliding was more intensive during Late Pleistocene and Holocene, reflecting activation of tectonic movements in this part of Baikal rift system. 相似文献
504.
K. Yu. Vasilieva E. A. Bakay V. B. Ershova R. R. Khusnitdinov A. K. Khudoley E. V. Kozlova S. A. Soloveva 《Moscow University Geology Bulletin》2016,71(6):445-450
The Riphean rocks of the Baikit anteclise have been examined using pyrolysis Rock–Eval 6 to evaluate the subsidence history and erosion level. The studied Riphean rocks have the МK3–МK4 catagenesis grade. Based on the catagenesis of organic matter we propose a model of maximum burial before the beginning of the accumulation of Vendian deposits. Estimated calculations of subsidence and erosion have shown that the assessed catagenesis grade could be reached at a depth of 7 km, while the erosion level was approximately 5–7 km. 相似文献
505.
New approaches, which expand the ideas about the compositions and structures of the mantle of the Earth and terrestrial planets, are considered. New data indicate a more fractional structure of the deep layers of the Earth and the Moon. The experimental results at high pressures and temperatures allow modeling the change in the structure and properties of the most important components of the composition of the mantle and cores of the Earth and Moon, as well as the gas (Jupiter and Saturn) and ice (Uranus and Neptune) giants. 相似文献
506.
了解华南各岩石圈块体壳幔结构和各向异性方面的差异是揭示华南深部构造演化的基础。本文利用布设于华南的两条宽频地震测线观测数据,采用多种地震学方法对华南的地壳上地幔结构和各向异性进行了研究。接收函数结果表明,华南地区地壳厚度和岩石圈厚度都较薄,地壳厚度自东南沿海向西北内陆增厚,扬子克拉通的泊松比(波速比)低于华夏块体,表明扬子克拉通地壳较华夏块体更偏长英质。约北纬29°以北的扬子克拉通地幔转换带厚度明显增厚,可能是由地幔转换带底部停滞的冷的古太平洋板片或中生代克拉通碰撞残留造成的。层析成像结果显示华南上地幔具有很强的横向差异性,上地幔中的强烈低速异常体可能对应了晚中生代发生广泛岩浆作用时的岩浆房和岩浆通道。台湾下方的上地幔存在南北横向差异明显的高速异常,分别对应台湾南部向东俯冲的欧亚板块及台湾北部向北俯冲的菲律宾海板块。俯冲的欧亚板块在台湾南部是连续的,而在台湾中北部,由于与菲律宾海板块的相互作用,俯冲的欧亚板块被折断。剪切波分裂结果显示,以江绍断裂为界,华夏块体与扬子克拉通的岩石圈地幔各向异性存在明显的横向变化,表明两者的构造演化过程有显著差异。 相似文献
507.
508.
509.
510.