全文获取类型
收费全文 | 6679篇 |
免费 | 715篇 |
国内免费 | 626篇 |
专业分类
化学 | 1069篇 |
晶体学 | 92篇 |
力学 | 681篇 |
综合类 | 130篇 |
数学 | 4607篇 |
物理学 | 1441篇 |
出版年
2024年 | 4篇 |
2023年 | 63篇 |
2022年 | 76篇 |
2021年 | 106篇 |
2020年 | 180篇 |
2019年 | 212篇 |
2018年 | 189篇 |
2017年 | 221篇 |
2016年 | 254篇 |
2015年 | 197篇 |
2014年 | 331篇 |
2013年 | 581篇 |
2012年 | 310篇 |
2011年 | 402篇 |
2010年 | 339篇 |
2009年 | 380篇 |
2008年 | 420篇 |
2007年 | 421篇 |
2006年 | 354篇 |
2005年 | 331篇 |
2004年 | 280篇 |
2003年 | 260篇 |
2002年 | 301篇 |
2001年 | 256篇 |
2000年 | 252篇 |
1999年 | 223篇 |
1998年 | 183篇 |
1997年 | 180篇 |
1996年 | 117篇 |
1995年 | 82篇 |
1994年 | 66篇 |
1993年 | 49篇 |
1992年 | 40篇 |
1991年 | 46篇 |
1990年 | 23篇 |
1989年 | 33篇 |
1988年 | 31篇 |
1987年 | 23篇 |
1986年 | 17篇 |
1985年 | 30篇 |
1984年 | 31篇 |
1983年 | 15篇 |
1982年 | 22篇 |
1981年 | 17篇 |
1980年 | 14篇 |
1979年 | 16篇 |
1978年 | 12篇 |
1977年 | 4篇 |
1976年 | 7篇 |
1973年 | 4篇 |
排序方式: 共有8020条查询结果,搜索用时 19 毫秒
101.
102.
数量级在物理实验中的应用 总被引:2,自引:0,他引:2
介绍了数量级在物理实验设计、实验失败原因分析、误差分析及实验结果判断方面的应用. 相似文献
103.
Young C. Kim Mikhail A. Anisimov Jan V. Sengers Erik Luijten 《Journal of statistical physics》2003,110(3-6):591-609
The character of critical behavior in physical systems depends on the range of interactions. In the limit of infinite range of the interactions, systems will exhibit mean-field critical behavior, i.e., critical behavior not affected by fluctuations of the order parameter. If the interaction range is finite, the critical behavior asymptotically close to the critical point is determined by fluctuations and the actual critical behavior depends on the particular universality class. A variety of systems, including fluids and anisotropic ferromagnets, belongs to the three-dimensional Ising universality class. Recent numerical studies of Ising models with different interaction ranges have revealed a spectacular crossover between the asymptotic fluctuation-induced critical behavior and mean-field-type critical behavior. In this work, we compare these numerical results with a crossover Landau model based on renormalization-group matching. For this purpose we consider an application of the crossover Landau model to the three-dimensional Ising model without fitting to any adjustable parameters. The crossover behavior of the critical susceptibility and of the order parameter is analyzed over a broad range (ten orders) of the scaled distance to the critical temperature. The dependence of the coupling constant on the interaction range, governing the crossover critical behavior, is discussed. 相似文献
104.
S. Alpay E. Yu. Emel'yanov Z. Ercan 《Proceedings of the American Mathematical Society》2004,132(12):3627-3628
In this paper we give a characterization of order ideals in Riesz spaces.
105.
Dynamic systems described by nonlinear differential equations of the second order are studied. It is assumed that certain
preliminary information on the dissipative or elastic characteristics of systems is known. A new approach is demonstrated
to obtaining full information on unknown or partially known characteristics of a system from measurements of not only displacements
but also velocities and accelerations
__________
Published in Prikladnaya Mekhanika, Vol. 41, No. 6, pp. 139–143, June 2005. 相似文献
106.
Bilal Chanane. 《Mathematics of Computation》2005,74(252):1793-1801
The purpose in this paper is to compute the eigenvalues of Sturm-Liouville problems with quite general separated boundary conditions nonlinear in the eigenvalue parameter using the regularized sampling method, an improvement on the method based on Shannon sampling theory, which does not involve any multiple integration and provides higher order estimates of the eigenvalues at a very low cost. A few examples shall be presented to illustrate the power of the method and a comparison made with the the exact eigenvalues obtained as squares of the zeros of the exact characteristic functions.
107.
在齐次Morrey-Herz空间上建立了高阶交换子~$T^{m}_{b,l}$ 和 ~$M^{m}_{b,l}$的有界性,其中~$T^{m}_{b,l}$ 和 ~$M^{m}_{b,l}$ 是由分数次积分算子和分数次极大算子分别与~BMO($R^{n}$)函数生成的高阶交换子. 相似文献
108.
CHEN Bao-Zhen HUANG Zu-Qia 《理论物理通讯》2004,42(9)
The theoretical signal-pressure curves are calculated from approximate analytical solutions of the coupledequations describing the third order parametric wave mixing in a gas-filled capillary of femto-second laser pulses. Thecomparison with the corresponding experimental curves suggests that the following three factors exert important influ-ences on the degree of fitting between the theoretical and experimental results: the walk-off, the phase modulation, andthe third order harmonic of idler pulse. 相似文献
109.
第二类变型Bessel函数Kn(z)在自变量趋于无穷时就是指数变小的,使用多项式逼近的方法求解往往误差很大.采用指数变换和J.P.Boyd的有理Chebyshev多项式计算第二类变型Bessel函数,得到了令人满意的在较大范围内有效的解. 相似文献
110.
We establish the similarity between certain Volterra integral operators and the Riemann--Liouville fractional integration operator as well as the existence of a triangular transformation operator for integro-differential equations of fractional order. The results obtained are consistent with similar results for the case of integer order. 相似文献