全文获取类型
收费全文 | 105篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
测绘学 | 2篇 |
地球物理 | 11篇 |
地质学 | 41篇 |
海洋学 | 12篇 |
天文学 | 36篇 |
自然地理 | 5篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 5篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2014年 | 4篇 |
2013年 | 9篇 |
2012年 | 7篇 |
2011年 | 4篇 |
2010年 | 6篇 |
2009年 | 13篇 |
2008年 | 7篇 |
2007年 | 8篇 |
2005年 | 1篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1995年 | 1篇 |
1978年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有107条查询结果,搜索用时 578 毫秒
1.
2.
3.
4.
Bikmaev I. F. Irtuganov E. N. Nikolaeva E. A. Sakhibullin N. A. Gumerov R. I. Sklyanov A. S. Glushkov M. V. Khamitov I. M. Borisov V. D. Burenin R. A. Zaznobin I. A. Krivonos R. A. Lyapin A. R. Medvedev P. S. Meshcheryakov A. V. Sazonov S. Yu. Sunyaev R. A. Khorunzhev G. A. Gilfanov M. R. 《Astronomy Letters》2021,47(5):277-290
Astronomy Letters - Results of the spectroscopic observations at the 1.5-m Russian–Turkish telescope for another group of 12 X-ray sources discovered by the eROSITA telescope onboard the SRG... 相似文献
5.
Zaznobin I. A. Burenin R. A. Lyapin A. R. Khorunzhev G. A. Afanasiev V. L. Grokhovskaya A. A. Dodonov S. N. Eselevich M. V. Uklein R. I. Bikmaev I. F. Khamitov I. M. Gilfanov M. R. Lyskova N. S. Medvedev P. S. Sunyaev R. A. 《Astronomy Letters》2021,47(3):141-149
Astronomy Letters - We present the first results of our program of optical observations for galaxy clusters from the Lockman Hole X-ray survey with the eROSITA telescope onboard the SRG space... 相似文献
6.
7.
GLONASS time is the reference for all time scales aboard GLONASS satellites. It is derived from the Central Synchronizer (CS),
which consists of an ensemble of hydrogen clocks (HC) having a instability of (1...3) × 10−14 (averaging interval 24 hours). The CS time is compared to UTC(SU) in a differential mode using a TV channel of the Technical
TV Center. Presently the error of GLONASS time is within 20...150 ns; however, there is a potential to decrease this value
to 15 to 50 ns (3σ).
The paper discusses the possible benefits of mutual phase comparisons between the HCs to determine the grouped frequency standard.
These comparisons are averaged daily. The approach yields an accuracy of better than 10 ns (3σ) for CS, bringing the expected
GLONASS time accuracy to the level of 15 to 50 ns (3σ). ? 2001 John Wiley & Sons, Inc. 相似文献
8.
The main episode of Cenozoic volcanic activity occurred simultaneously with formation of the Sayan—Baikal uplift, before the rift depressions were initiated. Volcanism and rifting in this region have developed as independent processes, connected with each other only by an ultimate primary mantle energy source. The volcanic regions do not coincide with the rift depressions, except in the Tunka graben.Chemical features of the volcanics show that during the entire period of volcanic activity there was a complex alternation of basaltic lavas of alkaline, intermediate and tholeiitic composition. Both alkaline and subalkaline lavas are distributed over the entire volcanic region, excepting the Tunka depression where tholeiitic lavas are predominant. However, there is neither mineralogical nor chemical evidence for the existence of two separate magma types within the Baikal rift zone.Judging by the presence of high-pressure, lherzolitic megacrysts of clinopyroxene, and to a lesser extent titaniferous biotite and amphibole in alkaline basalts, variations of lava chemistry are connected with high-pressure fractionation of initial melts, which was more complete for sources outside the rift zone. The predominance of tholeiitic lavas in the Tunka depression is likely to have been caused by a higher degree of partial melting and quick ascent of magma to the surface, facilitated by a high geothermal gradient under the depression where crustal extension is taking place. 相似文献
9.
V. N. Kozhevnikov S. G. Skublov Yu. B. Marin P. V. Medvedev Yu. Systra V. Valencia 《Doklady Earth Sciences》2010,431(1):318-323
Using local procedures, the new results on the isotope ages and composition of mineral inclusions were obtained for detrital
zircons from Paleoproterozoic Jatulian terrigenous quartzites and polymictic conglomerates in Central and Western Karelia.
For Eastern Laurasia, signs of the existence of Hadean and ancient Eoarchean matter were found for the first time (zircon
grains of 3871 ± 38.6 and 3837 ± 42.1 Ma concordant ages). The multimodal distribution of ages within 3.45−2.61 Ga was revealed.
The discovery of the oldest zircon grains provides the conditions for valid global correlations of geological events that
determined the deposition and formation of the continental crust of the North Atlantic supercraton. 相似文献
10.