全文获取类型
收费全文 | 88840篇 |
免费 | 18493篇 |
国内免费 | 9054篇 |
专业分类
化学 | 77856篇 |
晶体学 | 1105篇 |
力学 | 4252篇 |
综合类 | 571篇 |
数学 | 8270篇 |
物理学 | 24333篇 |
出版年
2024年 | 171篇 |
2023年 | 1050篇 |
2022年 | 1989篇 |
2021年 | 2282篇 |
2020年 | 3250篇 |
2019年 | 4501篇 |
2018年 | 2773篇 |
2017年 | 2583篇 |
2016年 | 5678篇 |
2015年 | 5951篇 |
2014年 | 6526篇 |
2013年 | 8060篇 |
2012年 | 7960篇 |
2011年 | 7298篇 |
2010年 | 6447篇 |
2009年 | 6360篇 |
2008年 | 6326篇 |
2007年 | 5168篇 |
2006年 | 4718篇 |
2005年 | 4235篇 |
2004年 | 3413篇 |
2003年 | 2992篇 |
2002年 | 3669篇 |
2001年 | 2719篇 |
2000年 | 2358篇 |
1999年 | 1392篇 |
1998年 | 850篇 |
1997年 | 760篇 |
1996年 | 719篇 |
1995年 | 585篇 |
1994年 | 534篇 |
1993年 | 433篇 |
1992年 | 390篇 |
1991年 | 368篇 |
1990年 | 291篇 |
1989年 | 234篇 |
1988年 | 181篇 |
1987年 | 148篇 |
1986年 | 163篇 |
1985年 | 121篇 |
1984年 | 87篇 |
1983年 | 82篇 |
1982年 | 56篇 |
1981年 | 50篇 |
1980年 | 43篇 |
1979年 | 41篇 |
1978年 | 33篇 |
1977年 | 39篇 |
1976年 | 29篇 |
1973年 | 35篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
991.
992.
Kui Zhao Xiuqin Lu Yehao Cheng Qingli Li Min Li Zhichang Li Jiyu Guo Shuyuan Li Qinghua Zhang Xiaobin Song Chenglie Jiang 《Zeitschrift für Physik A Hadrons and Nuclei》1994,348(2):95-98
Angular distributions of elastic and inelastic scattering have been measured for152Sm+12C at 63.2 MeV and148Nd+16O at 90.9 MeV. An evident interference pattern in the inelastic scattering has been observed for the first time in a strong Coulomb coupling system.We are indebted to Dr. S. Pieper for supplying the Ptolemy Program. One of us (Chenglie Jiang) would like to acknowledge the Argonne National Laboratory for the opportunity given, to perform theoretical calculations with the code Ptolemy during his visit there. Thanks are also due to Mr. H. Folger (GSI, Germany) for supplying the targets. This work was supported in part by China National Nature Science Fundation. 相似文献
993.
We report a dynamical study of multiplicative diffusion coupled map lattices with the coupling between the elements only through the bifurcation parameter of the mapping function. We discuss the diffusive process of the lattice from an initially random distribution state to a homogeneous one as well as the stable range of the diffusive homogeneous attractor. For various coupling strengths we find that there are several types of spatiotemporal structures. In addition, the evolution of the lattice into chaos is studied. A largest Lyapunov exponent and a spatial correlation function have been used to characterize the dynamical behavior. (c) 1996 American Institute of Physics. 相似文献
994.
995.
Akiba Y Beavis D Beery P Britt HC Budick B Chasman C Chen Z Chi CY Chu YY Cianciolo V Cole BA Costales JB Crawford HJ Cumming JB Debbe R Engelage J Fung SY Gonin M Gushue S Hamagaki H Hansen O Hayano RS Hayashi S Homma S Kaneko H Kang J Kaufman S Kehoe WL Kurita K Ledoux RJ Levine MJ Miake Y Morrison DP Morse RJ Moskowitz B Nagamiya S Namboodiri MN Nayak TK Olness J Parsons CG Remsberg LP Roehrich D Rothschild P Sakurai H Sangster TC Seto R Soltz R Stankus P Steadman SG Stephans GS Sung T 《Physical review letters》1996,76(12):2021-2024
996.
997.
Summary In this paper it is proved that, for any positive integern 2, 3 (mod 4),n 7, there exists an incomplete idempotent Schröder quasigroup with one hole of size two IISQ(n, 2) except forn = 10. It is also proved that for any positive integern 0, 1 (mod 4), there exists an idempotent Schröder quasigroup ISQ(n) except forn = 5 and 9. These results completely determine the spectrum of ISQ(n) and provide an application to the packing of a class of edge-coloured block designs.Research supported by NSERC grant A-5320.Research supported by NSFC grant 19231060-2. 相似文献
998.
Bing Wei 《Graphs and Combinatorics》1996,12(1):385-395
For a graphG, let
3 = min{
i=1
3
d(ui): {u1, u2, u3} is an independent set ofG} and
= min{
i=1
3
d(ui) –
is an independent set ofG}. In this paper, we shall prove the following result: LetG be a 1-tough graph withn vertices such that
3 n and
– 4. ThenG is hamiltonian. This generalizes a result of Fassbender [2], a result of Flandrin, Jung and Li [3] and a result of Jung [5].Supported in part by das promotionsstipendium nach dem NaFöG and the Post-Doctoral Foundation of China. 相似文献
999.
1000.
A computational kinetics model of the CuBr laser with added hydrogen is presented. The space-time behaviour of the lasers and lasants is described in detail. Besides the discharge field, it is confirmed that the dissociation/recombination of the CuBr molecule plays an important role in the plasma electron temperature. The radial field, which peaks at 30% of the discharge field and has two opposite directions along the radius, results in the skin of electron density and the black centre of the large-bore laser beam. 相似文献