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71.
A queue layout of a graph consists of a linear order of its vertices, and a partition of its edges into queues, such that no two edges in the same queue are nested. In this paper, we show that the n-dimensional hypercube Qn can be laid out using n−3 queues for n?8. Our result improves the previously known result for the case n?8. 相似文献
72.
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74.
Yingping Mou 《哲学杂志》2013,93(35):3361-3380
AbstractIn the recent studies of the unconventional physics in cuprate superconductors, one of the central issues is the interplay between charge order and superconductivity. Here the mechanism of the charge-order formation in the electron-doped cuprate superconductors is investigated based on the t-J model. The experimentally observed momentum dependence of the electron quasiparticle scattering rate is qualitatively reproduced, where the scattering rate is highly anisotropic in momentum space, and is intriguingly related to the charge-order gap. Although the scattering strength appears to be weakest at the hot spots, the scattering in the antinodal region is stronger than that in the nodal region, which leads to the original electron Fermi surface is broken up into the Fermi pockets and their coexistence with the Fermi arcs located around the nodal region. In particular, this electron Fermi surface instability drives the charge-order correlation, with the charge-order wave vector that matches well with the wave vector connecting the hot spots, as the charge-order correlation in the hole-doped counterparts. However, in a striking contrast to the hole-doped case, the charge-order wave vector in the electron-doped side increases in magnitude with the electron doping. The theory also shows the existence of a quantitative link between the single-electron fermiology and the collective response of the electron density. 相似文献
75.
A physically-based, rate and length-scale dependent strain gradient crystal plasticity framework was employed to simulate the polycrystalline plastic deformation at the microscopic level in a large-grained, commercially pure Ni sample. The latter was characterised in terms of the grain morphology and orientation (in the bulk) by micro-beam Laue diffraction experiments carried out on beamline B16 at Diamond Light Source. The corresponding finite element model was developed using a grain-based mesh with the specific grain orientation assignment appropriate for the sample considered. Sample stretching to 2% plastic strain was simulated, and a post-processor was developed to extract the information about the local lattice misorientation (curvature), enabling forward-prediction of the Laue diffraction patterns. The ‘streaking’ phenomenon of the Laue spots (anisotropic broadening of two-dimensional (2D) diffraction peaks observed on the 2D detector) was correctly captured by the simulation, as constructed by direct superposition of reflections from different integration points within the diffraction gauge volume. Good agreement was found between the images collected from experiments and simulation patterns at various positions in the sample. 相似文献
76.
In the integrated circuit manufacturing process, the critical area extraction is a bottleneck to the layout optimization and the integrated circuit yield estimation. In this paper, we study the problem that the missing material defects may result in the open circuit fault. Combining the mathematical morphology theory, we present a new computation model and a novel extraction algorithm for the open critical area based on the net flow-axis. Firstly, we find the net flow-axis for different nets. Then, the net flow-edges based on the net flow-axis are obtained. Finally, we can extract the open critical area by the mathematical morphology. Compared with the existing methods, the nets need not to divide into the horizontal nets and the vertical nets, and the experimental results show that our model and algorithm can accurately extract the size of the open critical area and obtain the location information of the open circuit critical area. 相似文献
77.
We aim to theoretically investigate the focusing property of a 4Pi configuration under the illumination of azimuthally polarized high-order Bessel–Gaussian beams. The radial component is produced in the focal region through the introduction of a spiral phase plate. The focal region differs from the zero radial intensity component of the azimuthally polarized beams without the spiral phase plate. The spherical focal spot is generated by selecting an appropriate annular obstruction. The position of the focal spot can be shifted. 相似文献
78.
The finite difference model is coupled with a cellular automaton (CA) model to simulate dendrite growth in TIG (tungsten inert‐gas) weld molten pool of nickel‐based alloys. Based on the macro finite difference computation of the thermal field of the whole weldment, the micro CA model is used to simulate grain formation process in 2‐dimension area within weld molten pool. The results illustrate that the complicated thermal field and solute field can lead to complex grain morphologies in weld molten pool. The primary dendrite spacing changes during welding solidification process and the final primary dendrite spacing is decided by the thermal field, solute field and other parameters. And it is indicated that the grain boundary segregation has important relationship with welding speed. The grain boundary segregations become more severe as the welding speed increases when the other parameters are kept unchanged. (© 2007 WILEY ‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
79.
Results of an experimental study of turbulent breakdown in gradient boundary layer at high freestream turbulence are reported.
For the first time it is shown that, like the flat-plate boundary layer, the wing boundary layer at high freestream turbulence
is modulated with streaky structures. One of possible mechanisms underlying the generation of turbulence spots in wing boundary
layer is modelled assuming the interaction of streaky structures with high-frequency waves. Qualitative and quantitative data
concerning the evolution of streaky structures in swqpt-wing boundary layer and in swept-wing boundary layer are presented.
Certain differences between the evolution of streaky structures in wing boundary layer and in flat-plate boundary layer are
revealed.
This work was supported by the President of the Russian Federation (Grants NSh-454.2008.1, MK- 101.2007.1), by the Russian
Foundation for Basic Research (Grant No. 05-01-00034), by the Ministry of Education and Science of the Russian Federation
(Grant No. RNP 2.1.2.3370), and by the Russian Government (State Contract No. 02.513.12.0043). 相似文献
80.
本文利用多尺度方法研究了包含孔洞金属材料在冲击加载条件下的动力学行为. 该多尺度方法结合了分子动力学和有限元方法,分子动力学方法运用于局部缺陷区域,而有限元方法运用于整个模型区域,两种方法之间使用桥尺度函数进行连接. 计算结果既包括了系统宏观的物理信息,如应变场、应力场、温度场等,也得到了微观原子的物理信息,如原子能量和位置坐标等. 结合以上的模拟结果,发现孔洞的坍塌与材料屈服强度和冲击强度有关,而孔洞坍塌和坍塌过程中对微喷射原子的压缩过程是形成局部热点的主要原因. 同时也发现孔洞坍塌形成的位错和局部热点可以导致局部绝热剪切带更容易形成.
关键词:
微孔洞
热点
冲击加载
多尺度方法 相似文献