全文获取类型
收费全文 | 408篇 |
免费 | 17篇 |
国内免费 | 28篇 |
专业分类
测绘学 | 4篇 |
大气科学 | 49篇 |
地球物理 | 76篇 |
地质学 | 141篇 |
海洋学 | 22篇 |
天文学 | 131篇 |
综合类 | 10篇 |
自然地理 | 20篇 |
出版年
2023年 | 4篇 |
2022年 | 3篇 |
2021年 | 10篇 |
2020年 | 16篇 |
2019年 | 11篇 |
2018年 | 17篇 |
2017年 | 24篇 |
2016年 | 24篇 |
2015年 | 10篇 |
2014年 | 13篇 |
2013年 | 23篇 |
2012年 | 15篇 |
2011年 | 32篇 |
2010年 | 31篇 |
2009年 | 27篇 |
2008年 | 10篇 |
2007年 | 9篇 |
2006年 | 15篇 |
2005年 | 6篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 6篇 |
1999年 | 5篇 |
1998年 | 7篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 8篇 |
1994年 | 4篇 |
1993年 | 7篇 |
1992年 | 3篇 |
1991年 | 8篇 |
1990年 | 10篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1984年 | 7篇 |
1983年 | 10篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 2篇 |
1977年 | 5篇 |
1976年 | 2篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1972年 | 4篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有453条查询结果,搜索用时 377 毫秒
191.
A model of a quiescent prominence with nonparallel structural elements, based on a study of the K Ca+ line fine structure of two quiescent prominences. The dependences of the radial velocities on the height found for the structural elements making up the prominence (Gigolashvili and Zhugzhda, 1982) gives the information on the inner spatial structure of the prominence. Analysis of the available data allows us to suggest an alternative model of a quiescent prominence. 相似文献
192.
Sh. S. Kholikov O. S. Burtseva A. V. Serebryanskiy Sh. A. Ehgamberdiev 《Astronomy Letters》2004,30(8):577-581
We analyze the pattern of behavior of p-mode wave packets with solar cycle using TON one-day helioseismic data with a high spatial resolution. The time—distance method is used to perform this task. We make an attempt to determine the variations in the travel time of acoustic waves at maximum and minimum solar activity; at maximum activity, this time decreases by 2 s compared to that at minimum activity to a depth of 0.8R⊙. In addition, the correlation amplitudes of acoustic wave packets from minimum to maximum solar activity were found to decrease by 10–20% for all angular distances. 相似文献
193.
Junyue Yan Huadong Yao Jianglong Li Zhiyi Tang Guorong Jiang Wenyu Sh Xunqiang Li Yiguo Xiao 《海洋学报(英文版)》2003,22(3):369-383
With the data observed from the Second SCS Air-Sea Flux Experiment on the Xisha air-sea flux research tower, the radiation budget, latent, sensible heat fluxes and net oceanic heat budgets were caculated before and after summer monsoon onset. It is discovered that, after summer monsoon onset, there are considerable changes in air-sea fluxes, especially in latent heat fluxes and net oceanic heat budget. Furthermore, the analyzed results of five synoptic stages are compared. And the characteristics of the flux transfer during different stages around onset of South China Sea monsoon are discussed. The flux change shows that there is an oceanic heat accumulating process during the pre-onset and the break period, as same as oceanic heat losing process during the onset period. Moreover, latent fluxes, the water vapor moving to the continent, even the rainfall appearance in Chinese Mainland also can be influenced by southwester. Comparing Xisha fluxes with those obtained from the Indian Ocean and the western Pacific Ocean, their differences may be obeerved. It is the reason why SSTs can keep stableover the South China Sea while they decrease quickly over the Arabian Sea and the Bay of Bengal aftermonsoon onset. 相似文献
194.
A. P. Afanasenkov M. B. Skvortsov A. M. Nikishin Sh. M. Murzin A. A. Polyakov 《Moscow University Geology Bulletin》2008,63(3):131-139
The structure and formation evolution of the principal North Caspian zones (North Caspian Basin, Karakul-Smushkovskii Foredeep, South Emba Foredeep, Karpinsky Range Fold Zone, Mangyshlak-Central Ustyurt Fold Zone, etc.) are discussed. Drilling data and seismic profiles were utilized in the study, and an analysis of hydrocarbon systems has been performed. 相似文献
195.
196.
M. Sh. Gigolashvili 《Solar physics》1984,93(2):317-324
A brief quantitative review of the determination of the chemical composition of the Sun and stars is given. The method of estimation of the total amount of hydrogen atoms in a prominence is considered.The values of relative abundances of some infrequent elements in the solar atmosphere are refined using metal emission lines in the spectrum of a quiescent prominence. The most probable values of relative abundances for itrium Y1×10–9, zirconium Zr2×10–9, and scandium Sc3.8×10–9 are derived. 相似文献
197.
T.?I.?BabukhinaEmail author A.?V.?Gan’shin R.?V.?Zhuravlev A.?N.?Luk’yanov Sh.?Sh.?Maksyutov 《Russian Meteorology and Hydrology》2016,41(5):335-343
The estimate of the release of radioactive substances (133Xe, 131I, and 137Cs) into the atmosphere from the Fukushima Daiichi nuclear disaster is presented. It was obtained using the FLEXPART Lagrangian dispersion model and the data of local ground-based measurements of radiation dose rate. The computation period covers the active phase of the nuclear disaster that lasted 20 days after the tsunami. To get the quantitative characteristics of emissions of radioactive substances, the inverse modeling based on the Bayesian approach is used. The emissions were estimated for three altitudes. The total emissions are equal to 2.1 + 0.4 kg (14 000 + 2700 PBq) for 133Xe, (3.8 + 0.4) x 10-2 kg (174 + + 18 PBq) for 131I, and 5.7 + 1.2 kg (18 + 4 PBq) for 137Cs that is consistent with the results of other studies. Retrieved emissions were used to provide the forward modeling for mapping the areas of radionuclide deposition. The developed method of retrieving the emission of radioactive substances makes a useful instrument that operationally estimates and localizes the areas of potential pollution in case of nuclear accidents and could be used for making decisions on the population evacuation. 相似文献
198.
It is demonstrated that the greatest influence of the variations in the groupiness of storm waves in the Baltic Sea concerns the highest waves. The variations in the height of less high waves are defined by wind speed. It is revealed that the height of 3% of the highest waves depends on their bandwidth: higher and lower waves are characterized by the larger and smaller set of frequencies, respectively. The significant wave height does not almost depend on the bandwidth. It is found that the spectrum of storm waves in the southwestern part of the Baltic Sea has a multi-peak structure which reflects the complex structure of waves consisting of several wave systems. Envelopes and individual waves of different frequency ranges superimpose, and extreme waves are generated. The probability of occurrence of extreme waves is maximum at the moments of the maximum development of wave groupiness. 相似文献
199.
Sh. K. Baltybaev G. V. Ovchinnikova V. A. Glebovitskii I. M. Vasil’eva N. G. Rizvanova 《Doklady Earth Sciences》2016,468(2):541-544
The isotopic–geochemical features of late and postorogenic granites of the S type and ambient migmatites are studied within the Russian part of the Svecofennian orogen of the Fennoscandinavian Shield. The spatial association of leucosomes of migmatites and granites of the S type and their similar petro- and geochemistry and distribution of Pb isotopes are evidence of the genetic similarity of their parental melts. The Borodinskoe pluton has a more primitive 206Pb/207Pb ratio, which indicates the presence of upper and U-poor lower crustal material in the source of granitic magmas. This conclusion is supported by the ?Nt(t) lower value of granites of this pluton relative to those of other plutons of the region. 相似文献
200.
Sh. M. Murzin 《Moscow University Geology Bulletin》2010,65(6):355-366
This study presents the consideration of the geological history and petroleum systems in the northern Caspian Sea basin (on
the basis of basin modeling using the TemisSuite2008 software package). The key patterns of the distribution of oil and gas
fields and their phase composition are described. Kulaginskii Ridge and the adjacent areas are considered. The preceding data
are generalized and new data are used. 相似文献