全文获取类型
收费全文 | 9629篇 |
免费 | 1320篇 |
国内免费 | 1159篇 |
专业分类
化学 | 7069篇 |
晶体学 | 121篇 |
力学 | 449篇 |
综合类 | 145篇 |
数学 | 1205篇 |
物理学 | 3119篇 |
出版年
2024年 | 32篇 |
2023年 | 174篇 |
2022年 | 338篇 |
2021年 | 349篇 |
2020年 | 366篇 |
2019年 | 417篇 |
2018年 | 348篇 |
2017年 | 331篇 |
2016年 | 481篇 |
2015年 | 450篇 |
2014年 | 594篇 |
2013年 | 676篇 |
2012年 | 794篇 |
2011年 | 805篇 |
2010年 | 578篇 |
2009年 | 542篇 |
2008年 | 648篇 |
2007年 | 533篇 |
2006年 | 498篇 |
2005年 | 417篇 |
2004年 | 371篇 |
2003年 | 299篇 |
2002年 | 360篇 |
2001年 | 293篇 |
2000年 | 206篇 |
1999年 | 161篇 |
1998年 | 117篇 |
1997年 | 88篇 |
1996年 | 100篇 |
1995年 | 100篇 |
1994年 | 90篇 |
1993年 | 59篇 |
1992年 | 52篇 |
1991年 | 72篇 |
1990年 | 45篇 |
1989年 | 34篇 |
1988年 | 23篇 |
1987年 | 32篇 |
1986年 | 23篇 |
1985年 | 29篇 |
1984年 | 14篇 |
1983年 | 22篇 |
1982年 | 16篇 |
1981年 | 14篇 |
1980年 | 11篇 |
1979年 | 12篇 |
1978年 | 13篇 |
1977年 | 9篇 |
1975年 | 10篇 |
1968年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
Li Taihua An Zhu Luo Zhengming Center for Radiation Physics Institute of Nuclear Science Technology Sichuan Union University Chengdu 《原子与分子物理学报》1997,(1)
MEASUREMENTSOFFeANDCuK-ShelIONIZATIONCROSSSECTIONSBYSLOWELECTRONIMPACTLiTaihuaAnZhuLuoZhengmingCenterforRadiationPhysics,Ins... 相似文献
33.
Guilin Wen Qing-Guo Wang Chong Lin Xu Han Guangyao Li 《Chaos, solitons, and fractals》2006,29(5):1142-1146
Synchronization under output feedback control with multiple random time delays is studied, using the paradigm in nonlinear physics—Chua’s circuit. Compared with other synchronization control methods, output feedback control with multiple random delay is superior for a realistic synchronization application to secure communications. Sufficient condition for global stability of delay-dependent synchronization is established based on the LMI technique. Numerical simulations fully support the analytical approach, in spite of the random delays. 相似文献
34.
35.
The influence of interdiffusion on eigenstates in an interdiffusion-induced GaAs/AlxGa1-xAs single-quantum-well structure is analysed numerically by the finite element method. In this approach, the confinement potential profile of the interdiffused quantum well structure is nonlinear and is modelled by an error function and, in particular, the nature of the effective mass of an electron is considered. The results show that the number of eigenstates and energy levels varies with the extent of the interdiffusion. Numerical results for the quasi-bound states in the quantum well structure with an applied electric field are also presented. 相似文献
36.
Differentkindsofopenchaincrownethershavebeensynthesizedasthemodelcompoundsofionophoresandtheirinteractionswithsodium,potassiumandrareearthionshavealsobeenstudiedl'z.PanshowedCe(III)yieldedalf1complexwithl,8-bis(8'-quinolyloxy)-3,6-dioxaandtheCe(IIl)ioncoordinatedbothtoetheroxygenandquinolinenitrogenatoms3.TUmInleridentifiedtwolanthanidenitratecomplexeshavingastoichiometryof3:2(3RE:2L)'.InordertostUdythefunctionsofbothquinolineandbenzenering,introducedintothepolyetherchain,a1inearpolyether… 相似文献
37.
38.
Bui An Ton 《Mathematical Methods in the Applied Sciences》1988,10(4):351-366
Let g is a positive increasing function with 1?g(0). The existence of a unique solution of the Navier-Stokes flow associated with Kε,γ and the convergence of the solution to that of the Euler equations as the viscosity goes to zero are established. 相似文献
39.
F. Štěrba J. Lipták Nguyen An Ninh J. Štěrbová J. Starý 《Czechoslovak Journal of Physics》1988,38(7):741-754
Excitation functions for the55Mn(p, p )55Mn,55Mn(p, n )55Fe and55Mn(p, )56Fe reactions are studied for proton beam energyE
p=1·3–2 MeV. The excitation functions are established from yield functions for -rays emitted from the first excited states of final nuclei. Many resonances are observed and competition of their decay into all three output channels is analysed. Spin-parity assignment for some resonant states in the56Fe compound nucleus is deduced.Participated partly in the course of his work on a Thesis.The authors wish to thank the staff of the Van de Graaff accelerator at Charles University in Prague for the efficient operation of the machine and dr. I. Wilhelm for the valuable technical help in the early period of the experimental work. One of us (N. A. N.) acknowledges the staff of the Dept. of Nuclear Physics of Charles University in Prague for the excellent working conditions. 相似文献
40.