全文获取类型
收费全文 | 930篇 |
免费 | 57篇 |
国内免费 | 30篇 |
专业分类
化学 | 577篇 |
晶体学 | 5篇 |
力学 | 35篇 |
综合类 | 13篇 |
数学 | 103篇 |
物理学 | 284篇 |
出版年
2023年 | 8篇 |
2022年 | 11篇 |
2021年 | 14篇 |
2020年 | 26篇 |
2019年 | 25篇 |
2018年 | 16篇 |
2017年 | 19篇 |
2016年 | 40篇 |
2015年 | 40篇 |
2014年 | 47篇 |
2013年 | 46篇 |
2012年 | 61篇 |
2011年 | 68篇 |
2010年 | 40篇 |
2009年 | 34篇 |
2008年 | 73篇 |
2007年 | 60篇 |
2006年 | 52篇 |
2005年 | 39篇 |
2004年 | 47篇 |
2003年 | 20篇 |
2002年 | 22篇 |
2001年 | 18篇 |
2000年 | 22篇 |
1999年 | 12篇 |
1998年 | 13篇 |
1997年 | 2篇 |
1996年 | 10篇 |
1995年 | 6篇 |
1994年 | 6篇 |
1993年 | 21篇 |
1992年 | 15篇 |
1991年 | 13篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 5篇 |
1979年 | 2篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1966年 | 3篇 |
1965年 | 1篇 |
1936年 | 1篇 |
1863年 | 1篇 |
排序方式: 共有1017条查询结果,搜索用时 342 毫秒
111.
Michel H. Geoffroy Célia Jean-Alexis Alain Piétrus 《Journal of Global Optimization》2008,42(1):111-120
We prove that the metric regularity of set-valued mappings is stable under some Wijsman-type perturbations. Then, we solve
a variational inclusion viewed as a limit-problem using assumptions on a sequence of associated problems. Finally, we apply
our results to classical methods for solving variational inclusions.
相似文献
112.
M. Pi X. Viñas M. Barranco G. la Rana S. Leray C. Ngô E. Tomasi 《Nuclear Physics A》1984,426(1):163-180
A finite-temperature Thomas-Fermi method has been used to study the nucleon flux between two hot semi-infinite slabs of nuclear matter in arbitrary relative motion. As an application, we estimate the imaginary part of the optical potential associated with nucléon transfer at the strong absorption radius. Analytical fits to the exact results are given for head-on and tangential collisions at zero temperature. 相似文献
113.
In his book (3), Pietsch presents the problem of a direct construction of the injective hull of an operator ideal on loca. lly convex spaces. We construct the infective hull of an arbitrary operator ideal on locally convex spaces using the functor, where and B cover the family of all equicontinuous subsets of E'(L is the category of all locally convex spaces). If the operator ideal is bounded, we ob tain its infective hull using seminorm ideals. 相似文献
114.
PiLing 《高校应用数学学报(英文版)》2004,19(4):417-428
Using Picard‘s theorem and the l.eray-Schauder fixed point theorem to reinvestigate the area-preserving convex curve flow in the plane which is considered as a coupled system and thus different from the setting handled by Gage. 相似文献
115.
We have investigated a material made of C60Ti6H12 molecules using the classical molecular dynamic simulation. The system was studied in a wide range of temperatures, from solid to fluid. Several physical characteristics of endohedral fullerene were calculated for various temperatures: the mean square displacement, the translational and angular velocity autocorrelation function, the translational diffusion coefficient and the Lindemann index. We have observed a reduction in the rotational freedom of fullerene decorated with TiH2 functionality groups in comparison with the pure fullerene sample. 相似文献
116.
我国是DVD播放机和家庭影院放大器、扬声器系统的生产和消费大国。据有关行业协会统计,我国国产DVD播放机一年的销量达到3000万台,各种大大小小的国产家庭影院放大器超过700万台,国产扬声器系统则达1000万套以上,加上在我国销售的外国产品,我国消费者购买的数量则更为可观。 相似文献
117.
Jung-Pil Yang S. H. Pi Y. P. Kim Young G. Kim 《Journal of magnetism and magnetic materials》1992,110(3):L261-L263
The structures and compositions of the Nd-rich phases in the sintered Nd15Fe77B8 magnets have been investigated. Two different Nd-rich phases of the fcc and dhcp (double hexagonal close packed) structures were present. Microstructural examinations revealed that oxygen played an important role in the structure of the Nd-rich phase. Wavelength Dispersive Spectrometry (WDS) and Auger Electron Spectroscopy (AES) analyses showed that the fcc Nd-rich phase contained a considerable amount of oxygen (about 20 at%), but the dhcp Nd-rich phase had a much lower amount of oxygen. 相似文献
118.
Proton spin-lattice relaxation times as a function of temperature for two kinds of binuclear copper complexes with antiferromagnetic exchange interactionJS1S2 have been measured in order to understand the relaxation effects in exchange clusters. It is shown that the results reflect the coupling of the nuclear and electron subsystems; in the rangekT<J the coupling of the subsystems is modulated by temperature independent processes, in the rangekT≥J the temperature dependence of the dynamics of the electron subsystem is manifested. The response of the nuclear subsystem to the change in the nature of magnetic excitations is discovered. 相似文献
119.
H.Pi Piehкicyh B.A. Кomapobcкicyй 《Journal of Quantitative Spectroscopy & Radiative Transfer》1976,16(3):217-252
Data on classification of spectra and energy levels of atoms of rare earth elements with unfilled 4f-shells have been collected, systematized and analyzed. A brief account is given of methods for determining transition probabilities and lifetimes of the excited states of atoms and ions. Oscillator strengths for spectral lines of Nd(I), Sm(I), Eu(I), Gd(I), Dy(I), Tm(I) and Yb(I) have been measured using Rojdestvensky's hook method. Lifetimes of some of the excited states of Eu(I), Yb(I) and Yb(II) have been determined by using simultaneously the methods of delayed coincidence, hooks, and total absorption. Our results have been compared with those of other investigators. Atoms with unfilled 4f-shells show some regularities. 相似文献
120.
Thorne's method for obtaining transport coefficients in a binary rigid-sphere mixture is reexamined. First, a close look is taken at the way in which the point where the Enskog functionsx
ij
are evaluated is introduced. Second, the calculation of the fluxes in the system and the transport coefficients is given. Thorne's results are found to be correct and independent of the choice of the point where the transfer plane is located. This does not hold true for the diffusion flux. It is shown that a different diffusion force is obtained for each selection and that only those diffusional effects which are of first order in the density are consistent with irreversible thermodynamics. 相似文献