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Malcolm A. Halcrow Colin A. Kilner Mark Thornton‐Pett 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):711-713
The title compound, [Cu(C27H40BN6)2]·2CH2Cl2, contains a four‐coordinate CuII ion lying on a crystallographic inversion centre, giving rise to a near‐regular square‐planar stereochemistry. There is an axial contact of 2.71 Å between the Cu ion and ligand B—H group, although this is unlikely to correspond to a significant `agostic' interaction. 相似文献
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M. L. Hamilton R. Peverall G. A. D. Ritchie L. J. Thornton J. H. van Helden 《Applied physics. B, Lasers and optics》2009,97(3):715-722
We have demonstrated the production of ∼1.9 μm near-infrared radiation by using difference frequency generation within a 5%
MgO doped PPLN crystal by coupling ∼735 nm radiation from a tunable external cavity diode laser with relatively high powered
532 nm radiation from both Nd:YVO3 and Nd:YAG lasers. The radiation produced is of low power, ∼15 μW, and was used in conjunction with the sensitivity enhancing
techniques of wavelength modulation spectroscopy (WMS) and cavity enhanced absorption spectroscopy (CEAS). Experiments were
carried out on rotationally resolved transitions in the combination bands of NH3 and CO2 in the 1.9 μm region. An α
min value of 3.6×10−6 cm−1 Hz−1/2 was achieved for WMS measurements on CO2. A comparable α
min value of 2.2×10−6 cm−1 Hz−1/2 was achieved for NH3 using CEAS. The low NIR power indicates that despite the level of MgO doping quoted for the crystal, under prolonged exposure
photorefractive damage has occurred. 相似文献
267.
Irene Nobeli John B. O. Mitchell Alexander Alex Janet M. Thornton 《Journal of computational chemistry》2001,22(7):673-688
The Biomolecular Ligand Energy Evaluation Protocol (BLEEP) is a knowledge‐based potential derived from high‐resolution X‐ray structures of protein–ligand complexes. The performance of this potential in ranking the hypothetical structures resulting from a docking study has been evaluated using fifteen protein–ligand complexes from the Protein Data Bank. In the majority of complexes BLEEP was successful in identifying the native (experimental) binding mode or an alternative of low rms deviation (from the native) as the lowest in energy. Overall BLEEP is slightly better than the DOCK energy function in discriminating native‐like modes. Even when alternative binding modes rank lower than the native structure, a reasonable energy is assigned to the latter. Breaking down the BLEEP scores into the atom–atom contributions reveals that this type of potential is grossly dominated by longer range interactions (>5 Å), which makes it relatively insensitive to small local variations in the binding site. However, despite this limitation, the lack, at present, of accurate protein–ligand potentials means that BLEEP is a promising approach to improve the filtering of structures resulting from docking programs. Moreover, BLEEP should improve with the continuously increasing number of complexes available in the PDB. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 673–688, 2001 相似文献
268.
Colin Thornton 《中国颗粒学报》2010,8(2)
The Discrete Element Method (DEM) was originally devised by Cundall and Strack (1979), as a technique to examine the micromechanics of granular media with the anticipation that this would lead to more physically reliable continuum theories to describe the quasi-static deformation of granular material such as sand. However, the methodology models the evolution of a system of particles as a dynamic process. Consequently there have been numerous publications of the application of DEM to an increasingly wider v... 相似文献
269.
Michael G. S. Londesborough Jonathan Bould Josef Holub John D. Kennedy Mark Thornton‐Pett Bohumil tíbr 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1423-1424
The title compound, 1,1,2,2‐tetracarbonyl‐1,2‐μ‐carbonyl‐4,11‐dimethylsulfido‐closo‐1,2‐dicobaltadodecaborane, [Co2(C4H20B10S2)(CO)5], has a closo 12‐vertex {1,2‐Co2B10H8} structure with SMe2 ligands at the exo‐4‐ and 11‐positions. The cluster displays close structural similarities to the SEt2 analogue. 相似文献
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M. Khoury A. Gunther S. Miličić J. Rack S.M. Goodnick D. Vasileska T.J. Thornton D.K. Ferry 《Applied Physics A: Materials Science & Processing》2000,71(4):415-421
We present experimental results for two types of quantum dots, which are embedded within a silicon metal-oxide-semiconductor
structure. Evidence is found for single-electron charging at low temperature, and for an asymmetric shape of the dot. First
results of simulations of these dots are presented.
Received: 14 April 2000 / Accepted: 17 April 2000 / Published online: 6 September 2000 相似文献