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61.
C. R. Davidson D. G. Foursa A. Lucero O. Sinkin W. Patterson A. Pilipetskii G. Mohs Neal S. Bergano 《中国光学快报(英文版)》2010,(9):831-836
We provide a review of our recent 100-Gb/s, high spectral efficiency (SE) experiment targeting transoceanic and regional undersea transmission distances. We demonstrated that simple pre-filtering at the transmitter together with a maximum a posteriori probability (MAP) detection algorithm can significantly improve SE. We transmitted 96×100-Gb/s pre-filtered polarization division multiplexed return-to-zero quadrature phase shift keyed (PDM-RZ-QPSK) channels with 300% SE over 10608 km using 52-km spans of 150-μm 2 fiber and simple single-stage erbium-doped fiber amplifiers (EDFAs). We also achieved 400% SE over 4368 km using similar techniques. 相似文献
62.
We have performed a series of neutron diffraction experiments from the magnetic order and the vortex lattice in single crystal
ErNi2B2C. The incommensurate magnetic structure develops additional even harmonics below the ‘ferromagnetic’ ordering temperature,
T
F of 2.3 K. This feature and the existence of rods of diffuse scattering suggest the development of ferromagnetic microdomain
walls. The magnetic structure is very sensitive to the application of a magnetic field with changes in modulation vector and
harmonic content. Studies of the vortex lattice show the presence of a 45° reorientation transition and a distorted hexagonal
to square transition as a function of applied field. Further distortions of the vortex lattice occur at T
N, but no changes are seen at T
F. 相似文献
63.
Jiao H van Eikema Hommes NJ Schleyer PR de Meijere A 《The Journal of organic chemistry》1996,61(8):2826-2828
[5]Pericyclynes were investigated at high ab initio and density functional levels. On the basis of the geometric, energetic, and magnetic criteria of aromaticity, [5]pericyclynes are not homoaromatic despite their intriguing structure. The strain energy of [5]pericyclynes is negligible. 相似文献
64.
65.
Johan K. Terlouw Peter C. Burgers Henk Hommes 《Journal of mass spectrometry : JMS》1979,14(10):574-576
Characterization of [C4H5O]+ ions in the gas phase using their metastable ion and collisional activation spectra shows that the three isomeric ions HC?C? \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}H? OCH3, CH3O? \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}?C?CH2 and ? OCH3 related to the two stable [C3H3]+ cations [HC?C? CH2]+ and are stable for ≥ 10?5s. In contrast to the formation of cyclopropenium ions, it is found that the methoxy cyclopropenium ion is not generated from acyclic precursor molecules. The small but significant intensity differences found in the collisional activation spectra of [C3H3]+ ions generated from HC?C? CH2I and HC?C? CH2Cl possibly indicate the presence of [C3H3]+ ions of different structures. 相似文献
66.
Puchta R Galle M van Eikema Hommes N Pasgreta E van Eldik R 《Inorganic chemistry》2004,43(26):8227-8229
The ligand exchange mechanism of solvated lithium cations has been studied using DFT calculations (RB3LYP/6-311+G**). The water exchange mechanism on [Li(H(2)O)(4)](+) was found to be limiting associative (A) involving a five-coordinate intermediate, whereas ammonia exchange on [Li(NH(3))(4)](+) was found to follow an associative interchange (I(a)) mechanism. The suggested mechanisms are discussed in reference to available experimental and theoretical data. 相似文献
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