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991.
给出了方差未知时两总体均值比较的近似方法(Welch-Satterthwaite方法),Bayes方法和一个Monte Carlo模拟算法,并用一个算例进行了比较. 相似文献
992.
Existence of a family of locally invariant probability measures for large scale flows in enclosed temperate sea is proved.
This model is extremely important for understanding the meso-scale phenomena in oceans. The techniques used are those developed
by Albeverio and his collaborators. 相似文献
993.
Xiubin Ren Xiangyun Guo . College of Chemistry Chemical Engineering Xi’an University of Science Technology Xi’an Shaanxi China . State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan Shanxi 《天然气化学杂志》2011,20(5):503-506
Monte Carlo method was applied to simulate the oscillatory behavior during partial oxidation of methane under non-isothermal condition. The simulation was performed to examine the influences of heat transfer constant and particle size on the kinetic oscillation. The oscillatory period and amplitude were observed to increase with the increase of heat transfer constant. The increase of catalyst particle size was found to result in short oscillatory period and more or less regular oscillations combined with the formation of oxide down to L=100. 相似文献
994.
995.
旋流扩散燃烧中旋流数对热NO生成的影响 总被引:4,自引:0,他引:4
本文对旋流扩散燃烧进行了数值模拟,研究旋流数对热NO生成的影响,其中对湍流采用Reynolds应力方程模型,对燃烧采用EBU-Arrhenius模型,对热NO生成采用设定PDF的模型。预报了不同旋流数下轴向和切向的平均和脉动速度、温度和NO浓度,指出随着旋流数的增大,计算得到的出口平均NO浓度首先升高然后下降。这一趋势和本文作者最近的实验结果的趋势一致.随着旋流数的增大,湍流脉动首先下阵然后升高,而进口附近的温度上升,二者综合效果造成上述趋势、因此在实际燃烧器中,完全靠改变族流数来控制NO生成是不现实的。应该采取其他方法来降低NO的生成。 相似文献
996.
Over the past 15 years direct numerical simulations (DNS) of turbulent flow and particle image velocimetry (PIV) have provided
the opportunity to obtain information about a turbulent velocity field simultaneously at a large number of locations. This
paper gives a personal viewpoint of how these techniques are providing new insights about the Reynolds stress producing structures
in turbulence generated by flow over a smooth boundary.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
997.
A dynamical Lie algebraic method has been applied to treating the quantum dynamics of dissociative adsorption of H_2 on a static flat metal surface. An LEPS potential energy surface has been used to describe the interaction of H_2 with Ni(100) surface. The dependence of the initial state-selected dissociation probability was obtained analytically on the initial kinetic energy and time. A comparison with other theoretical calculations and experiments is made. The results show that the method can be effectively used to describe the dynamics of reactive gas-surface scattering. 相似文献
998.
Three-dimensional cellular automaton simulation of tumour growth in inhomogeneous oxygen environment
H. Hötzendorfer W. Estelberger F. Breitenecker 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(2):177-189
Cellular automaton theory has previously been used to study cell growth. In this study, we present a three-dimensional cellular automaton model performing the growth simulation of normal and cancerous cells. The necessary nutrient supply is provided by an artificial arterial tree which is generated by constrained constructive optimization. Spatial oxygen diffusion is approximated again by a cellular automaton model. All results could be illustrated dynamically by three-dimensional volume visualization. Because of the chosen modelling approach, an extension of the model to simulate angiogenic processes is possible. 相似文献
999.
Feichtinger Gustav Andreas J. Novak 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(3):197-211
In this paper we present a simple time-continuous behavioural model of habit formation. Addictive behaviour is damped by a threshold which adapts itself to the habit. This adaptive behaviour of the threshold may lead to periodic fluctuations of the consumption rate, the habit and the threshold. It turns out that both a low adjustment rate of the threshold as well as a steep consumption function favour oscillatory patterns. 相似文献
1000.
Pan Xiao Jun Wang Rong Yang Fu-Jiu Ke Meng-Fen Xia Yi-Long Bai 《Acta Mechanica Sinica》2013,29(5):676-681
Since rate effect of materials plays a key role in impact engineering, the microscopic mechanism of rate effect is investigated at molecular level in this paper. The results show that rate effect on the strength of atomic system is closely related to the coupled evolution of atomic motions and potential landscapes. Accordingly, it becomes possible to develop a new algorithm of molecular simulation, which could properly and efficiently demonstrate strain rate effect under a wide range of loading rates and unveil the mecha- nisms underlying the strain rate effects. 相似文献