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991.
Electrochemical Studies of Cytochrome c on Electrodes Modified by Single-Wall Carbon Nanotubes 总被引:2,自引:0,他引:2
Single wallcarbonnanotubes (SWNTs)modifiedgoldelectrodeswerepreparedbyusingtwodifferentmethods .Theelectrochemicalbehaviorofcytochromeconthemodifiedgoldelectrodeswasinves tigated .ThefirstkindofSWNT modifiedelectrode (notedasSWNT/Auelectrode)waspreparedbytheadsorptionofcarboxyl terminatedSWNTsfromDMFdispersiononthegoldelectrode .TheoxidativelyprocessedSWNTtipswerecovalentlymodifiedbycouplingwithamines (AET)toformamidelinkage .ViaAu—Schemicalbonding ,theself assembledmonolayerofthi… 相似文献
992.
利用 Brick wall 方法,计算非球坐标系,非渐近平直的 torus like 黑洞背景下标量场的自由能和熵. 结果表明,在非渐近平直时空,黑洞具有内外视界时,
所得熵不仅与外视界面积有关,而且也是内视界的函数.进一步证明,用内外视界参量表达的熵,在黑洞辐射温度趋于零时,黑洞的熵也趋于零,它满足能斯特定理,可视为黑洞的普朗克绝对熵. 相似文献
993.
In the present paper, the collapsing dynamics of a laser-induced cavitation bubble near the edge of a rigid wall is experimentally investigated with a high-speed photography system. For a symmetrical setup, the two primary control parameters of the bubble collapsing behavior include the equivalent maximum bubble radius and the distance between the bubble and the edge of the rigid wall. Based on the bubble interface deformation during the collapsing process, three typical cases are identified for the categorization of the phenomenon with the influences of the parameters revealed. Through a quantitative analysis of the obtained high-speed photos, the motions of the bubble interface in different directions are given together with the calculations of the bubble centroid. The primary findings of the present paper could be summarized in terms of the bubble-edge distance as follows. When the bubble is close to the edge, the movement of the bubble interface near the edge will be restricted with a clear neck formation in the middle part of the bubble. For this case, the edge could delay the bubble collapsing time up to 22% of the Rayleigh collapsing time. When the bubble is of the medium distance to the edge, the differences of the expansion or shrinkage of the bubble interface among different directions will be reduced with an olive-shaped bubble formed during the collapsing process. For this range of parameters, the bubble moves rapidly toward the edge especially during the final collapsing stage. When the bubble is far away from the edge, the bubble will be a nearly spherical one. 相似文献
994.
David P. Lockard Li-Shi Luo Seth D. Milder Bart A. Singer 《Journal of statistical physics》2002,107(1-2):423-478
A careful comparison of the performance of a commercially available Lattice-Boltzmann Equation solver (PowerFLOW) was made with a conventional, block-structured computational fluid-dynamics code (CFL3D) for the flow over a two-dimensional NACA-0012 airfoil. The results suggest that the version of PowerFLOW used in the investigation produced solutions with large errors in the computed flow field; these errors are attributed to inadequate resolution of the boundary layer for reasons related to grid resolution and primitive turbulence modeling. The requirement of square grid cells in the PowerFLOW calculations limited the number of points that could be used to span the boundary layer on the wing and still keep the computation size small enough to fit on the available computers. Although not discussed in detail, disappointing results were also obtained with PowerFLOW for a cavity flow and for the flow around a generic helicopter configuration. 相似文献
995.
996.
Ronald Fisch 《Journal of statistical physics》2006,125(3):789-799
The statistics of domain walls for ground states of the 2D Ising spin glass with +1 and −1 bonds are studied for L × L square lattices with L ≤ 48, and p = 0.5, where p is the fraction of negative bonds, using periodic and/or antiperiodic boundary conditions. When L is even, almost all domain walls have energy E
dw
= 0 or 4. When L is odd, most domain walls have E
dw
= 2. The probability distribution of the entropy, S
dw
, is found to depend strongly on E
dw
. When E
dw
= 0, the probability distribution of |S
dw
| is approximately exponential. The variance of this distribution is proportional to L, in agreement with the results of Saul and Kardar. For E
dw
= k > 0 the distribution of S
dw
is not symmetric about zero. In these cases the variance still appears to be linear in L, but the average of S
dw
grows faster than L. This suggests a one-parameter scaling form for the L-dependence of the distributions of S
dw
for k> 0.
PACS: 75.10.Nr, 75.40.Mg, 75.60.Ch, 05.50.+q 相似文献
997.
998.
本文利用超声脉冲反射法,对人体血管壁声衰减特性进行了离体测量,给出了人体血管壁声能量衰减参数的测量值。这对超声在医学领域的应用以及超声连体非介入血栓消溶有着十分重要的意义。 相似文献
999.
The interaction between impacting and splashed droplets and air motion plays a fundamental role on the mixture formation process, which is a crucial aspect for the correct operation of modern DI Diesel engines as it greatly influences the combustion process and the exhaust emissions. A complete understanding of spray impingement is quite complex. A mixed numerical–experimental approach is proposed in this paper. 相似文献
1000.
We construct a set of exact ground states with a localized ferromagnetic domain wall and an extended spiral structure in a quasi-one-dimensional deformed flat-band Hubbard model. In the case of quarter filling, we show the uniqueness of the ground state with a fixed magnetization. The ground states with these structures are degenerate with the all-spin-up and all-spin-down states. This property of the degeneracy is the same as the domain wall solutions in the XXZ Heisenberg–Ising model. We derive a useful recursion relation for the normalization of the domain wall ground state. Using this recursion relation, we discuss the convergence of the ground state expectation values of arbitrary local operators in the infinite-volume limit. In the ground state of the infinite-volume system, the translational symmetry is spontaneously broken by this structure. We prove that the cluster property holds for the domain wall ground state and excited states. We also estimate bounds of the ground state expectation values of several observables, such as one- and two-point functions of spin and electron number density. 相似文献