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981.
We describe the experimental test of a quantum key distribution performed with a two-way protocol without using entanglement. An individual incoherent eavesdropping is simulated and induces a variable amount of noise on the communication channel. This allows a direct verification of the agreement between theory and practice. 相似文献
982.
983.
In this paper, a Z4-equivariant quintic planar vector field is studied. The Hopf bifurcation method and polycycle bifurcation method are combined to study the limit cycles bifurcated from the compounded cycle with 4 hyperbolic saddle points. It is found that this special quintic planar polynomial system has at least four large limit cycles which surround all singular points. By applying the double homoclinic loops bifurcation method and Hopf bifurcation method, we conclude that 28 limit cycles with two different configurations exist in this special planar polynomial system. The results acquired in this paper are useful for studying the weakened 16th Hilbert's Problem. 相似文献
984.
An existence result of multiple solutions for a fourth-order Sturm-Liouville boundary value problem with variable parameters is established. As a consequence, three solutions for a boundary value problem with a fourth-order equation in a complete form are obtained. Our approach is based on variational methods. 相似文献
985.
986.
Recently, the first two authors characterized in Di Nola and Dvure?enskij (2009) [1] subdirectly irreducible state-morphism MV-algebras. Unfortunately, the main theorem (Theorem 5.4(ii)) has a gap in the proof of Claim 10, as the example below shows. We now present a correct characterization and its correct proof. 相似文献
987.
Python语言因为语法简洁、功能全面、开发的程序具有可移植性而拥有十分广阔的应用市场.Python在诸多方面都有应用,如科学计算、应用开发以及计算机科学教育等.本文就热敏电阻测量实验的数据处理问题进行了分析,同时也进行了系统的图形化界面设计以及用Python语言编写相关的脚本来实现了实验数据的数据库存储功能. 相似文献
988.
Di Wu Xun Chen Shenghui Chen Shunxing Lu Fenghua Wang Yumei Zhang 《Journal of Macromolecular Science: Physics》2013,52(3):504-511
Steadyshear and oscillatory shear rheological measurements were performed to characterize the solution rheological behavior of poly(3,3′-diaminodiphenylsulfone terephthaloylchloride) (P(3,3′-DDS-TPC)) in dimethyl sulfoxide (DMSO). The effects of temperature, concentration, and weight-average molar mass () on the rheological properties were investigated. From the temperature dependence of zero-shear viscosity, the flow activation energies, Eη, of P(3,3′-DDS-TPC)/DMSO solutions were calculated. Both the overlap concentration, C*, and the entanglement concentration, Ce, were determined from the concentration dependence of the specific viscosity ηsp. All the P(3,3′-DDS-TPC) solutions, we studied, can be separated into three regimes: the dilute, semidilute-unentangled, and entangled regime with slopes of 1, 1.3, and 3.9, of concentration versus ηsp plots, respectively, which are consistent with scaling predictions for flexible polymers in a good solvent. 相似文献
989.
E. Canè G. Di Lonardo L. Fusina W. Jerzembeck H. Bürger J. Breidung 《Molecular physics》2013,111(4):557-577
The high resolution infrared spectrum of 123SbD3 has been recorded in the 20–350?cm?1 range and in the regions of the ν1, ν3 and ν2, ν4 fundamental bands centred at 1350 and 600?cm?1, respectively. Splitting of the K′′?=?3, 6 lines have been observed both in the rotation and ro-vibration spectra. A large number of ‘perturbation allowed‘ transitions with selection rules Δ(k??l) =?±?3,?±?6, and?±?9 have been identified in all fundamental bands. Accurate ground state molecular parameters have been determined by means of a simultaneous fit of the rotational transitions and about 12?000 ground state combination differences from the infrared bands. The A and B reductions of the rotational Hamiltonian provided almost equivalent results. The molecular parameters of the ν i ?=?1 (i?=?1???4) states were obtained as a result of the simultaneous analysis of the ν1 (A1)/ν3 (E) stretching and of the ν2 (A1)/ν4 (E) bending dyads. In fact, the corresponding excited states are affected by strong perturbations due to rovibrational interactions of Coriolis and k-type that have been treated explicitly in the model adopted for the analysis. Improved effective ground state and equilibrium geometries were determined for the molecule and compared to those of 123SbH3. Ab initio calculations at the coupled cluster CCSD(T) level with an energy-consistent large-core pseudopotential and large basis sets were carried out to determine the equilibrium structure, the anharmonic force field, and the associated spectroscopic constants of 123SbH3 and 123SbD3. The theoretical results are in good agreement with the experimental data. 相似文献
990.