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101.
102.
SINGLE MACHINE SCHEDULING WITH CONTROLLABLE PROCESSING TIMES AND COMPRESSION COSTS (Part Ⅱ Heuristics for the General Case) 总被引:1,自引:0,他引:1
A single machine scheduling problem with controllable processing times and compression costs is considered. The objective is to find an optimal sequence to minimize the cost ofcompletion times and the cost of compression. The complexity of this problem is still unknown.In Part Ⅱ of this paper,the authors have considered a special case where the compression timesand the compression costs are equal among all jobs. Such a problem appears polynomiafiy solvable by developing an O(n^2) algorithm. In this part(Part Ⅱ ),a general case where the controllable processing times and the compression costs are not equal is discussed. Authors proposehere two heuristics with the first based on some previous work and the second based on the algorithm developed in Part Ⅱ . Computational results are presented to show the efficiency and therobustness of these heuristics. 相似文献
103.
AbstractThe pressure dependence of the structural, elastic, electronic and thermal properties of Kondo insulator SmB6 have been systematically studied by density functional theory combined with the quasi-harmonic Debye model. The calculated structure at zero pressure is in good agreement with the available experimental results at low temperature. The obtained elastic constants, bulk modulus and shear modulus indicate that SmB6 is mechanically stable and behaves in a brittle manner under the applied pressure 0–20 GPa, consistent with available experimental data. In addition, the elastic-relevant properties, Young’s modulus and the Poisson ratio manifest that increasing pressure results in an enhancement in the stiffness of the compound. It is found that unlike temperature, pressure has little effect on the heat capacity of SmB6. What more important is that we observed an insulator to metal phase transition at about 5.5 GPa through the disappearance of the band gap, well consistent with the experimental data. This transition has little effect on the physical properties of SmB6. 相似文献
104.
The sound generated by the unsteady motion of a vortex filament moving over a flat boundary with a sharp flow impedance discontinuity is studied theoretically. Theoretical results show that the vortex filament undergoes significant accelerating or decelerating motions and radiates sound at the instant when it moves across the plane of impedance discontinuity. The accelerations and decelerations of the vortex filament are shown to be the major mechanisms of sound generation. The sound so produced has a large low-frequency content such that the change in the flow impedance affects only the sound generation process but not the subsequent sound propagation to the far field. 相似文献
105.
We report the optimal design for hollow fiber inner-coated with metallic and multidielectric layers by using ray-optics theory. Transmission characteristics of the multilayer hollow fiber are more dependent on the film surface roughness in the IR region. Comparisons of fibers with smooth and rough films are made and discussed in detail. The optimal design for film thickness, inner radius, and the number of layers and refractive indices is presented. The calculation results are important for structure design, material selection, and fabrication when considering imperfections in film-coating techniques. Multilayer fibers are fabricated based on the calculation and experimental results agree with the theoretical ones. 相似文献
106.
Sonodynamic therapy (SDT) is a novel tumor therapy method. We investigated membrane fluidity, activity of the enzymes and membrane morphology in vitro post hematoporphyrin-SDT treatment. Furthermore, the potential mechanisms behind the changes in membrane fluidity and enzymic activity were discussed. Tumor cells were exposed to ultrasound at 1.75 MHz for up to 3 min in the presence and absence of hematoporphyrin. Fluorescence polarization, contents of Malonaldehyde, and levels of free fatty acid were assessed. Activity of enzymes was checked by the plumbic nitrate detection method. For the morphologic study, a scanning electron microscope was used to observe the cellular surface. Ultrasonically induced cell damage increased in the presence of HPD (from 15% to 24%). Compared with ultrasound treatment alone, the fluidity decreased from 5.037 to 3.908, malonaldehyde content and free fatty acid level increased from 0.743 nmol/mL to 0.979 nmol/mL and from 237.180 μmol/L to 730.769 μmol/L, respectively, post ultrasound combined with HPD treatment. Inactivity of adenylate cyclase and guanylate cyclase and significant deformation of the cellular surface were also observed post SDT treatment. Our results suggested that alterations in membrane modality and lipid composition played important roles in SDT-mediated inhibition of tumor growth, even inducing tumor cell death, which might be attributed to a sono-chemical activation mechanism. 相似文献
107.
108.
We report on the generation of high power superbroad spectrum bunched noise-like pulses from a passively mode-locked erbium-doped fiber ring laser without using the stretched-pulse technique. The maximum 3-dB spectral bandwidth of the noise-like pulses is about 93 nm with an energy of about 15 nJ. We further show numerically that the superbroad spectrum of the pulses is caused by the transform-limited feature of the pulses together with the Raman self-frequency shift effect. PACS 42.65.Dr; 42.55.Wd; 42.60.Fc; 42.81.Dp 相似文献
109.
A multilayer dielectric cylindrical mirror (MDCM) based on the one-dimensional omnidirectional reflection of a photonic crystal is presented. In this case, the refractive indices of the two materials are 1.6 (polystyrene) and 4.6 (tellurium), and the corresponding optimized thicknesses are 0.75a and 0.25a. A very high reflectance over a wide frequency range is observed. In this case, a is the lattice constant of the photonic crystal. In this band, the MDCM has good reflection and focal properties. Therefore, it is feasible to use the MDCM for integrated waveguide devices. As an example, an etched diffraction grating demultiplexer based on the MDCM is also proposed. Both the operational principle and design of the device are introduced. This provides a method for designing compact integrated waveguide devices. 相似文献
110.
In this paper, we investigate the Schr\"{o}dinger equation, which satisfies that the potential is asymptotical 0 at infinity in some measure-theoretic and the nonlinearity is sublinear growth. By using variant symmetric mountain lemma, we obtain infinitely many solutions for the problem. Moreover, if the nonlinearity is locally sublinear defined for $|u|$ small, we can also get the same result. In which, we show that these solutions tend to zero in $L^{\infty}(\mathbb{R}^{N})$ by the Br\"{e}zis-Kato estimate. 相似文献