全文获取类型
收费全文 | 12642篇 |
免费 | 2768篇 |
国内免费 | 703篇 |
专业分类
化学 | 4727篇 |
晶体学 | 92篇 |
力学 | 884篇 |
综合类 | 156篇 |
数学 | 2000篇 |
物理学 | 8254篇 |
出版年
2024年 | 24篇 |
2023年 | 105篇 |
2022年 | 321篇 |
2021年 | 357篇 |
2020年 | 358篇 |
2019年 | 405篇 |
2018年 | 343篇 |
2017年 | 401篇 |
2016年 | 572篇 |
2015年 | 513篇 |
2014年 | 746篇 |
2013年 | 1150篇 |
2012年 | 744篇 |
2011年 | 851篇 |
2010年 | 689篇 |
2009年 | 721篇 |
2008年 | 778篇 |
2007年 | 941篇 |
2006年 | 813篇 |
2005年 | 593篇 |
2004年 | 575篇 |
2003年 | 581篇 |
2002年 | 475篇 |
2001年 | 418篇 |
2000年 | 409篇 |
1999年 | 302篇 |
1998年 | 314篇 |
1997年 | 218篇 |
1996年 | 193篇 |
1995年 | 153篇 |
1994年 | 147篇 |
1993年 | 119篇 |
1992年 | 105篇 |
1991年 | 87篇 |
1990年 | 57篇 |
1989年 | 81篇 |
1988年 | 73篇 |
1987年 | 40篇 |
1986年 | 35篇 |
1985年 | 43篇 |
1984年 | 46篇 |
1983年 | 18篇 |
1982年 | 37篇 |
1981年 | 30篇 |
1980年 | 21篇 |
1979年 | 23篇 |
1978年 | 21篇 |
1977年 | 11篇 |
1976年 | 16篇 |
1973年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
92.
Sylvia Pulmannová 《International Journal of Theoretical Physics》2003,42(5):907-919
Tensor products of quantum logics and effect algebras with some known problems are reviewed. It is noticed that although tensor products of effect algebras having at least one state exist, in the category of complex Hilbert space effect algebras similar problems as with tensor products of projection lattices occur. Nevertheless, if one of the two coupled physical systems is classical, tensor product exists and can be considered as a Boolean power. Some applications of tensor products (in the form of Boolean powers) to quantum measurements are reviewed. 相似文献
93.
94.
Cordula Grüttner Knut Müller Joachim Teller Fritz Westphal Allan Foreman Robert Ivkov 《Journal of magnetism and magnetic materials》2007
Bionized nanoferrite (BNF) particles with high specific power absorption rates were synthesized in the size range of 20–100 nm by high-pressure homogenization for targeted cancer therapy with alternating magnetic fields. Several strategies were used to conjugate antibodies to the BNF particles. These strategies were compared using an immunoassay to find optimal conditions to reach a high immunoreactivity of the final antibody–particle conjugate. 相似文献
95.
Following our investigation of the USA Standard and Poor index anti-bubble that started in August 2000 (Quant. Finance 2 (2002) 468), we analyze 38 world stock market indices and identify 21 “bearish anti-bubbles” and six “bullish anti-bubbles”. An “anti-bubble” is defined as a self-reinforcing price trajectory with self-similar expanding log-periodic oscillations. Mathematically, a bearish anti-bubble is characterize by a power law decrease of the price (or of the logarithm of the price) as a function of time and by expanding log-periodic oscillations. We propose that bearish anti-bubbles are created by positive price-to-price feedbacks feeding overall pessimism and negative market sentiment further strengthened by inter-personal interactions. Bullish anti-bubbles are here identified for the first time. The most striking discovery is that the majority of European and Western stock market indices as well as other stock indices exhibit practically the same log-periodic power law anti-bubble structure as found for the USA S&P500 index. These anti-bubbles are found to start approximately at the same time, August 2000, in all these markets. This shows a remarkable degree of worldwide synchronization. The descent of the worldwide stock markets since 2000 is thus an international event, suggesting the strengthening of globalization. 相似文献
96.
LIU Zhongkui 《数学年刊B辑(英文版)》2004,25(1):129-138
Let (S,≤) be an ordered set. Recall that (S,≤) is artinian if every strictly decreasingsequence of elements of S is ?nite, and that (S,≤) is narrow if every subset of pairwiseorder-incomparable elements of S is ?nite. Let S be a commutative monoid. Unl… 相似文献
97.
A. Vukics H. Ritsch 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(3):585-599
We present a framework for efficiently performing Monte Carlo
wave-function simulations in cavity QED with moving particles. It
relies heavily on the object-oriented programming paradigm as realised
in C++, and is extensible and applicable for simulating open
interacting qua
ntum dynamics in general. The user is provided with a
number of “elements”, e.g. pumped moving particles, pumped lossy
cavity modes, and various interactions to compose complex interacting
systems, which contain several particles moving in electromagnetic
fields of various configurations, and perform wave-function
simulations on such systems. A number of tools are provided to
facilitate the implementation of new elements. 相似文献
98.
An efficient synthesis approach is developed which permits thecalculation of the steady-state frequency response of an assembly whichis comprised of linear components and nonlinear joints. Receptancematrices are used to characterize the linear components, which permitscondensation of the system to just the joint degrees-of-freedom.Furthermore, the calculated nonlinear joint forces are then used tostudy the power flow in the assembly, as well as detailed dynamicbehavior within the components. Integrated into the technique is acontinuation scheme which permits efficient parametric studies. 相似文献
99.
We consider the effects of quark masses to the perturbative thrust in e
+
e
− annihilation. In particular we show that perturbative power corrections resulting from non-zero quark masses considerably
alters the size of the non-perturbative power corrections and consequently, significantly changes the fitted value of αs. 相似文献
100.
M. Feng 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,18(3):371-377
The Raman interaction of a ultracold ion trapped with two travelling wave lasers is studied analytically with series solutions,
in the absence of the rotating wave approximation (RWA) and without restrictions of both the Lamb-Dicke limit and the weak
excitation regime. The comparison is made between our solutions and those obtained under the RWA in order to demonstrate the
validity region of the RWA. As a practical example, the preparation of Schr?dinger-cat states is proposed beyond the weak
excitation regime, using our calculations.
Received 12 March 2001 and Received in final form 16 October 2001 相似文献