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91.
T. Tsuboi 《Phase Transitions》2013,86(1-2):119-124
Two anomalous behaviors are observed in the Raman spectra of BaMnF4 at room temperature. One is that the number of Raman lines is smaller than that expected for the orthorhombic crystal structure with C 2ν 12 symmetry, the other is that, of the b(aa)c, a(bb)c, and b(cc)a scattering geometries giving the same A1-symmetry spectrum, the number of Raman lines in the b(aa)c spectrum is considerably smaller than those in the other two spectra. It is suggested that rotation of MnF6 octahedra about c-axis occurring in the orthorhombic phase is responsible for the former behavior, and Ba2+-ion displacement along a-axis for the latter one. 相似文献
92.
The electron paramagnetic resonance (EPR) spectral data (the g factors and hyperfine structure constants) and d–d transition spectra for the tetragonal Mo5+ centre in [Mo6O19][N(C4H9)4]3 salt are theoretically investigated from the complete diagonalization method (CDM) for a 4d1 ion in tetragonally compressed octahedron. The theoretical results are in good agreement with the experimental data. The dependency of the g factors of the ground state on the R∥(MoO bond length) has been studied. It is shown that the g factors varied with the R∥ approximately in a linear way. 相似文献
93.
94.
用激光诱导荧光(LIF)方法对芳香族化合物蒽进行了时间分辨谱研究,介绍了所用测试系统的组成和测试方法,获得了蒽的荧光强度-波长-时间三维立体图、峰值荧光时间图、等高图,并对实验结果进行了分析。研究表明,荧光产生的时间与峰值波长有关系,长波早于短波。 相似文献
95.
采用紫外-可见吸收光谱法现场监测了苯胺电化学聚合时的动力学降解过程,简单、直观地显示了阳极电位、酸度和苯胺浓度对降解过程的影响,结果表明,阳极电位越正、酸度越强、苯胺浓度越大,聚苯胺的降解速度越快。该方法得到的结果与聚苯胺膜在空白溶液中采用循环伏安法研究其降解动力学时得到的结果类似。 相似文献
96.
M. Marlo-Helle A. Harju R.M. Nieminen 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):286
We study ground states and far-infrared spectra (FIR) of two electrons in four-minima quantum-dot molecule in magnetic field by exact diagonalization. Ground states consist of altering singlet and triplet states, whose frequency, as a function of magnetic field, increases with increasing dot–dot separation. When the Zeeman energy is included, only the two first singlet states remain as ground states. In the FIR spectra, we observe discontinuities due to crossing ground states. Non-circular symmetry induces anticrossings, and also an additional mode above ω+ in the spin-triplet spectrum. In particular, we conclude that electron–electron interactions cause only minor changes to the FIR spectra and deviations from the Kohn modes result from the low-symmetry confinement potential. 相似文献
97.
The five lowest doubly excited deformational vibrational bands ν4 + ν6, 2ν6, ν3 + ν4, ν3 + ν6, and 2ν3 of PH2D have been recorded for the first time using a Bruker 120 HR interferometer with a resolution 0.0033 cm−1 and analysed. Some transitions belonging to a very weak band 2ν4 have been also assigned. From the fit 24 and 86, respectively, diagonal and resonance interaction parameters were obtained which reproduce 1089 upper energy levels obtained from more than 4600 assigned transitions with the rms deviation of 0.00059 cm−1. 相似文献
98.
G.?N.?TenEmail author T.?G.?Burova V.?I.?Baranov 《Journal of Applied Spectroscopy》2005,72(1):104-110
Calculations of the frequencies and absolute intensities of the IR bands of plane vibrations of thymine and N1,N3-deuterothymine in various phase states have been carried out. It has been shown that in the polycrystalline state thymine forms hydrogen bonds C2=O8...HN1 and C2=O8...HN3, and in an aqueous solution the intermolecular interaction is realized by means of the hydrogen bonds O8...HO and O...HN1.__________Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 1, pp. 99–105, January–February, 2005. 相似文献
99.
A. Abdollahi 《Proceedings of the American Mathematical Society》2008,136(9):3185-3193
Let be a conformal automorphism on the unit disk and be the composition operator on the Dirichlet space induced by . In this article we completely determine the point spectrum, spectrum, essential spectrum and essential norm of the operators and self-commutators of , which expose that the spectrum and point spectrum coincide. We also find the eigenfunctions of the operators.
100.
We study the effects of the next-nearest-neighbor hopping and nearest-neighbor interactions on topological phases in a one-dimensional generalized Kitaev model. In the noninteracting case, we define a topological number and calculate exactly the phase diagram of the system. With addition of the next-nearest-neighbor hopping, the change of phase boundary between the topological and trivial regions can be described by an effective shift of the chemical potential. In the interacting case, we obtain the entanglement spectrum, the degeneracies of which correspond to the topological edge modes, by using the infinite time-evolving block decimation method. The results show that the interactions change the phase boundary as adding an effective chemical potential which can be explained by the change of the average number of particles. 相似文献