全文获取类型
收费全文 | 73495篇 |
免费 | 2430篇 |
国内免费 | 61篇 |
专业分类
化学 | 45380篇 |
晶体学 | 540篇 |
力学 | 1349篇 |
综合类 | 1篇 |
数学 | 13198篇 |
物理学 | 15518篇 |
出版年
2023年 | 503篇 |
2022年 | 457篇 |
2021年 | 786篇 |
2020年 | 1042篇 |
2019年 | 1029篇 |
2018年 | 1491篇 |
2017年 | 1330篇 |
2016年 | 2578篇 |
2015年 | 2134篇 |
2014年 | 2161篇 |
2013年 | 4743篇 |
2012年 | 4590篇 |
2011年 | 4556篇 |
2010年 | 2961篇 |
2009年 | 2474篇 |
2008年 | 4011篇 |
2007年 | 3791篇 |
2006年 | 3417篇 |
2005年 | 3228篇 |
2004年 | 2753篇 |
2003年 | 2194篇 |
2002年 | 1956篇 |
2001年 | 1494篇 |
2000年 | 1446篇 |
1999年 | 1027篇 |
1998年 | 800篇 |
1997年 | 668篇 |
1996年 | 907篇 |
1995年 | 660篇 |
1994年 | 732篇 |
1993年 | 715篇 |
1992年 | 700篇 |
1991年 | 574篇 |
1990年 | 607篇 |
1989年 | 507篇 |
1988年 | 501篇 |
1987年 | 462篇 |
1986年 | 450篇 |
1985年 | 633篇 |
1984年 | 598篇 |
1983年 | 467篇 |
1982年 | 449篇 |
1981年 | 454篇 |
1980年 | 392篇 |
1979年 | 399篇 |
1978年 | 400篇 |
1977年 | 399篇 |
1976年 | 408篇 |
1974年 | 364篇 |
1973年 | 364篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
E. Liénard G. Ban J. Blieck D. Durand F. Duval X. Fléchard M. Herbane M. Labalme Y. Lemière F. Mauger A. Méry O. Naviliat-Cuncic D. Rodríguez J. C. Thomas 《Hyperfine Interactions》2006,172(1-3):29-33
We report on the status of the LPCTrap experiment, devoted to measure the β–ν angular correlation in the pure Gamow–Teller
decay of 6He. This measurement is motivated by the search for the presence of tensor type contributions to the weak interaction. The
6He ions are confined in a novel transparent Paul trap. The β particles and the recoil ions are detected in coincidence to
deduce the angular correlation parameter. The commissioning run performed in 2005 has given the proof of principle of this
experiment. Up to 105 coincidences were recorded during a second run in 2006. 相似文献
182.
Summary The gas chromatographic behaviour of crosslinked macroporous 2-hydroxyethyl methacrylate grafted with 2-methyloxazoline was
investigated and the range of applicability of the copolymer was assessed. Retention index values were measured on this copolymer
and compared with those obtained on the terpolymer 2-hydroxyethyl methacrylate-ethylene dimethacrylate-acrylonitrile. Rohrschneider
constants and efficiency data for selected sorbates are given. The use of this type of polymer in the separation of various
types of compounds is documented by various examples. 相似文献
183.
184.
185.
186.
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
187.
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
188.
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
189.
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
190.
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