全文获取类型
收费全文 | 52660篇 |
免费 | 1704篇 |
国内免费 | 19篇 |
专业分类
化学 | 31325篇 |
晶体学 | 277篇 |
力学 | 937篇 |
综合类 | 1篇 |
数学 | 10134篇 |
物理学 | 11709篇 |
出版年
2023年 | 367篇 |
2022年 | 311篇 |
2021年 | 524篇 |
2020年 | 738篇 |
2019年 | 680篇 |
2018年 | 1085篇 |
2017年 | 1000篇 |
2016年 | 1924篇 |
2015年 | 1552篇 |
2014年 | 1544篇 |
2013年 | 3514篇 |
2012年 | 3140篇 |
2011年 | 3034篇 |
2010年 | 2006篇 |
2009年 | 1672篇 |
2008年 | 2596篇 |
2007年 | 2314篇 |
2006年 | 2055篇 |
2005年 | 2073篇 |
2004年 | 1798篇 |
2003年 | 1512篇 |
2002年 | 1366篇 |
2001年 | 1069篇 |
2000年 | 1049篇 |
1999年 | 756篇 |
1998年 | 597篇 |
1997年 | 530篇 |
1996年 | 672篇 |
1995年 | 504篇 |
1994年 | 567篇 |
1993年 | 523篇 |
1992年 | 551篇 |
1991年 | 467篇 |
1990年 | 507篇 |
1989年 | 430篇 |
1988年 | 434篇 |
1987年 | 407篇 |
1986年 | 382篇 |
1985年 | 529篇 |
1984年 | 494篇 |
1983年 | 407篇 |
1982年 | 400篇 |
1981年 | 412篇 |
1980年 | 362篇 |
1979年 | 343篇 |
1978年 | 338篇 |
1977年 | 330篇 |
1976年 | 344篇 |
1974年 | 320篇 |
1973年 | 339篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
131.
132.
133.
J. Pisút N. Pisútová B. Tomásik 《The European Physical Journal C - Particles and Fields》2003,29(1):79-85
We present a few estimates of energy densities reached in heavy-ion collisions at the CERN SPS. The estimates are based on
data and models of proton-nucleus and nucleus-nucleus interactions. In all of these estimates the maximum energy density in
central Pb+Pb interactions is larger than the critical energy density GeV/fm3 following from lattice gauge theory computations. In estimates which we consider as realistic the maximum energy density
is about . In this way our analysis gives some support to claims that deconfined matter has been produced at the CERN SPS. Any definite
statement requires a deeper understanding of formation times of partons and hadrons in nuclear collisions. We also compare
our results with implicit energy estimates contained in earlier models of anomalous suppression in nuclear collisions.
Received: 3 February 2003 / Revised version: 5 March 2003 / Published online: 5 May 2003 相似文献
134.
In this paper a new multidimensional extension of the recently developed one-dimensional enclosure method called kite is given for interval global optimization. A more sophisticated version of the pruning technique based on the kite method is introduced. By the new componentwise approach all the one-dimensional theoretical results and procedures can be used in the higher-dimensional case. The possibilities in the implementation of the new algorithm together with numerical results on 40 standard test problems are presented. 相似文献
135.
J. L. Hernández–Pastora O. V. Manko V. S. Manko J. Martín E. Ruiz 《General Relativity and Gravitation》2004,36(4):781-797
The extended quadruple–Kerr metric is used to consider equilibrium states of four collinear Kerr particles. We explain our previous failure to solve numerically the full set of the balance equations, and we derive a self–consistent system of the axis conditions leading to the equilibrium of all four constituents which can be black holes or hyperextreme objects. The equilibrium configurations obtained in this paper exhibit similar features with those occurring in the systems of two Kerr particles, for instance, the balance of four Kerr black holes with positive masses does not seem possible. Equilibrium states of two identical compound Kerr objects are also discussed. 相似文献
136.
J. Mlynár J. Ongena The EFDA JET Contributions I. Duran M. Hron R. Pánek V. Petržílka F. Žáček 《Czechoslovak Journal of Physics》2004,54(3):C28
JET (Joint European Torus) is the largest tokamak in the world and the only fusion facility able to operate with Tritium, the fusion fuel, and Beryllium, the ITER first wall material. JET also features the most complete remote handling equipment for invessel maintenance. As a multinational research center, JET provides logistic experience in preparing for operation of the global facility, tokamak ITER.Experiments on JET are focused on ITER-relevant studies, in particular on detailing the operational scenarios (EL My H-modes and advanced regimes), on enhancing the heating systems, on developing diagnostics for burning plasmas etc. Pioneering real-time control techniques have been implemented that maximize performance and minimize internal disturbances of JET plasmas. In helium plasmas, ion cyclotron heating (ICRH) created fast α-particles, mimicking their populations in future burning plasmas. The recent successful Trace Tritium campaign provided important new data on fuel transport. Current enhancements on JET include a new ITER-like ELM-resilient high power ICRH antenna (7 MW) and over twenty new diagnostics that will further extend the JET scientific capabilities and push the facility even closer to the ITER parameters.A special mention is given to the involvement of the fusion experts from Association EURATOM-IPP.CR, who have been actively participating in the collective use of JET facility for more than three years. 相似文献
137.
Sylvia Pulmannová 《International Journal of Theoretical Physics》2004,43(7-8):1573-1585
Divisible effect algebras and their relations to convex effect algebras and MV-algebras are studied. A categorical equivalence between divisible effect algebras and rational vector spaces is proved. Infinitesimal, sharp and extremal elements in divisible effect algebras are studied and their relations to properties of the state space are shown. 相似文献
138.
Gábor Házi 《Central European Journal of Physics》2003,1(3):453-462
A general class of analytical solutions of the lattice Boltzmann equation is derived for two-dimensional, steady-state unidirectional
flows. A subset of the solutions that verifies the corresponding Navier-Stokes equations is given. It is pointed out that
this class includes, e.g., the Couette and the Poiseuille flow but not, e.g., the basic Kolmogorov flow. For steady-state
non-unidirectional flows, first and second order solutions of the lattice Boltzmann equation are derived. Practical consequences of the analysis
are mentioned. Differences between the technique applied here and those used in some earlier works are emphasized. 相似文献
139.
In the present paper, Daubechies' wavelets and the computation of their scaling coefficients are briefly reviewed. Then a new method of computation is proposed. This method is based on the work [7] concerning a new orthonormality condition and relations among scaling moments, respectively. For filter lengths up to 16, the arising system can be explicitly solved with algebraic methods like Gröbner bases. Its simple structure allows one to find quickly all possible solutions. 相似文献
140.
Anna Jenčová 《International Journal of Theoretical Physics》2004,43(7-8):1635-1649
We use a class of generalized relative entropies on density matrices to obtain one-parameter families of torsion-free affine connections. 相似文献